update deps

vendor/github.com/mattn/go-zglob/fastwalk/fastwalk.go

@@ -21,8 +21,8 @@ import (
 	"runtime"
 )
 
-// traverseLink is a sentinel error for fastWalk, similar to filepath.SkipDir.
-var traverseLink = errors.New("traverse symlink, assuming target is a directory")
+// TraverseLink is a sentinel error for fastWalk, similar to filepath.SkipDir.
+var TraverseLink = errors.New("traverse symlink, assuming target is a directory")
 
 // FastWalk walks the file tree rooted at root, calling walkFn for
 // each file or directory in the tree, including root.
@@ -35,7 +35,7 @@ var traverseLink = errors.New("traverse symlink, assuming target is a directory"
 //     any permission bits.
 //   * multiple goroutines stat the filesystem concurrently. The provided
 //     walkFn must be safe for concurrent use.
-//   * fastWalk can follow symlinks if walkFn returns the traverseLink
+//   * fastWalk can follow symlinks if walkFn returns the TraverseLink
 //     sentinel error. It is the walkFn's responsibility to prevent
 //     fastWalk from going into symlink cycles.
 func FastWalk(root string, walkFn func(path string, typ os.FileMode) error) error {
@@ -144,7 +144,7 @@ func (w *walker) onDirEnt(dirName, baseName string, typ os.FileMode) error {
 
 	err := w.fn(joined, typ)
 	if typ == os.ModeSymlink {
-		if err == traverseLink {
+		if err == TraverseLink {
 			// Set callbackDone so we don't call it twice for both the
 			// symlink-as-symlink and the symlink-as-directory later:
 			w.enqueue(walkItem{dir: joined, callbackDone: true})

vendor/github.com/mattn/go-zglob/zglob.go

@@ -111,6 +111,14 @@ func makePattern(pattern string) (*zenv, error) {
 }
 
 func Glob(pattern string) ([]string, error) {
+	return glob(pattern, false)
+}
+
+func GlobFollowSymlinks(pattern string) ([]string, error) {
+	return glob(pattern, true)
+}
+
+func glob(pattern string, followSymlinks bool) ([]string, error) {
 	zenv, err := makePattern(pattern)
 	if err != nil {
 		return nil, err
@@ -131,6 +139,16 @@ func Glob(pattern string) ([]string, error) {
 		}
 		path = filepath.ToSlash(path)
 
+		if followSymlinks && info == os.ModeSymlink {
+			followedPath, err := filepath.EvalSymlinks(path)
+			if err == nil {
+				fi, err := os.Lstat(followedPath)
+				if err == nil && fi.IsDir() {
+					return fastwalk.TraverseLink
+				}
+			}
+		}
+
 		if info.IsDir() {
 			if path == "." || len(path) <= len(zenv.root) {
 				return nil

vendor/github.com/spf13/pflag/flag.go

@@ -568,6 +568,10 @@ func UnquoteUsage(flag *Flag) (name string, usage string) {
 		name = "strings"
 	case "intSlice":
 		name = "ints"
+	case "uintSlice":
+		name = "uints"
+	case "boolSlice":
+		name = "bools"
 	}
 
 	return

vendor/golang.org/x/crypto/ssh/buffer.go

@@ -0,0 +1,97 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"io"
+	"sync"
+)
+
+// buffer provides a linked list buffer for data exchange
+// between producer and consumer. Theoretically the buffer is
+// of unlimited capacity as it does no allocation of its own.
+type buffer struct {
+	// protects concurrent access to head, tail and closed
+	*sync.Cond
+
+	head *element // the buffer that will be read first
+	tail *element // the buffer that will be read last
+
+	closed bool
+}
+
+// An element represents a single link in a linked list.
+type element struct {
+	buf  []byte
+	next *element
+}
+
+// newBuffer returns an empty buffer that is not closed.
+func newBuffer() *buffer {
+	e := new(element)
+	b := &buffer{
+		Cond: newCond(),
+		head: e,
+		tail: e,
+	}
+	return b
+}
+
+// write makes buf available for Read to receive.
+// buf must not be modified after the call to write.
+func (b *buffer) write(buf []byte) {
+	b.Cond.L.Lock()
+	e := &element{buf: buf}
+	b.tail.next = e
+	b.tail = e
+	b.Cond.Signal()
+	b.Cond.L.Unlock()
+}
+
+// eof closes the buffer. Reads from the buffer once all
+// the data has been consumed will receive io.EOF.
+func (b *buffer) eof() {
+	b.Cond.L.Lock()
+	b.closed = true
+	b.Cond.Signal()
+	b.Cond.L.Unlock()
+}
+
+// Read reads data from the internal buffer in buf.  Reads will block
+// if no data is available, or until the buffer is closed.
+func (b *buffer) Read(buf []byte) (n int, err error) {
+	b.Cond.L.Lock()
+	defer b.Cond.L.Unlock()
+
+	for len(buf) > 0 {
+		// if there is data in b.head, copy it
+		if len(b.head.buf) > 0 {
+			r := copy(buf, b.head.buf)
+			buf, b.head.buf = buf[r:], b.head.buf[r:]
+			n += r
+			continue
+		}
+		// if there is a next buffer, make it the head
+		if len(b.head.buf) == 0 && b.head != b.tail {
+			b.head = b.head.next
+			continue
+		}
+
+		// if at least one byte has been copied, return
+		if n > 0 {
+			break
+		}
+
+		// if nothing was read, and there is nothing outstanding
+		// check to see if the buffer is closed.
+		if b.closed {
+			err = io.EOF
+			break
+		}
+		// out of buffers, wait for producer
+		b.Cond.Wait()
+	}
+	return
+}

vendor/golang.org/x/crypto/ssh/certs.go

@@ -0,0 +1,519 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"sort"
+	"time"
+)
+
+// These constants from [PROTOCOL.certkeys] represent the algorithm names
+// for certificate types supported by this package.
+const (
+	CertAlgoRSAv01      = "ssh-rsa-cert-v01@openssh.com"
+	CertAlgoDSAv01      = "ssh-dss-cert-v01@openssh.com"
+	CertAlgoECDSA256v01 = "ecdsa-sha2-nistp256-cert-v01@openssh.com"
+	CertAlgoECDSA384v01 = "ecdsa-sha2-nistp384-cert-v01@openssh.com"
+	CertAlgoECDSA521v01 = "ecdsa-sha2-nistp521-cert-v01@openssh.com"
+	CertAlgoED25519v01  = "ssh-ed25519-cert-v01@openssh.com"
+)
+
+// Certificate types distinguish between host and user
+// certificates. The values can be set in the CertType field of
+// Certificate.
+const (
+	UserCert = 1
+	HostCert = 2
+)
+
+// Signature represents a cryptographic signature.
+type Signature struct {
+	Format string
+	Blob   []byte
+}
+
+// CertTimeInfinity can be used for OpenSSHCertV01.ValidBefore to indicate that
+// a certificate does not expire.
+const CertTimeInfinity = 1<<64 - 1
+
+// An Certificate represents an OpenSSH certificate as defined in
+// [PROTOCOL.certkeys]?rev=1.8.
+type Certificate struct {
+	Nonce           []byte
+	Key             PublicKey
+	Serial          uint64
+	CertType        uint32
+	KeyId           string
+	ValidPrincipals []string
+	ValidAfter      uint64
+	ValidBefore     uint64
+	Permissions
+	Reserved     []byte
+	SignatureKey PublicKey
+	Signature    *Signature
+}
+
+// genericCertData holds the key-independent part of the certificate data.
+// Overall, certificates contain an nonce, public key fields and
+// key-independent fields.
+type genericCertData struct {
+	Serial          uint64
+	CertType        uint32
+	KeyId           string
+	ValidPrincipals []byte
+	ValidAfter      uint64
+	ValidBefore     uint64
+	CriticalOptions []byte
+	Extensions      []byte
+	Reserved        []byte
+	SignatureKey    []byte
+	Signature       []byte
+}
+
+func marshalStringList(namelist []string) []byte {
+	var to []byte
+	for _, name := range namelist {
+		s := struct{ N string }{name}
+		to = append(to, Marshal(&s)...)
+	}
+	return to
+}
+
+type optionsTuple struct {
+	Key   string
+	Value []byte
+}
+
+type optionsTupleValue struct {
+	Value string
+}
+
+// serialize a map of critical options or extensions
+// issue #10569 - per [PROTOCOL.certkeys] and SSH implementation,
+// we need two length prefixes for a non-empty string value
+func marshalTuples(tups map[string]string) []byte {
+	keys := make([]string, 0, len(tups))
+	for key := range tups {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+
+	var ret []byte
+	for _, key := range keys {
+		s := optionsTuple{Key: key}
+		if value := tups[key]; len(value) > 0 {
+			s.Value = Marshal(&optionsTupleValue{value})
+		}
+		ret = append(ret, Marshal(&s)...)
+	}
+	return ret
+}
+
+// issue #10569 - per [PROTOCOL.certkeys] and SSH implementation,
+// we need two length prefixes for a non-empty option value
+func parseTuples(in []byte) (map[string]string, error) {
+	tups := map[string]string{}
+	var lastKey string
+	var haveLastKey bool
+
+	for len(in) > 0 {
+		var key, val, extra []byte
+		var ok bool
+
+		if key, in, ok = parseString(in); !ok {
+			return nil, errShortRead
+		}
+		keyStr := string(key)
+		// according to [PROTOCOL.certkeys], the names must be in
+		// lexical order.
+		if haveLastKey && keyStr <= lastKey {
+			return nil, fmt.Errorf("ssh: certificate options are not in lexical order")
+		}
+		lastKey, haveLastKey = keyStr, true
+		// the next field is a data field, which if non-empty has a string embedded
+		if val, in, ok = parseString(in); !ok {
+			return nil, errShortRead
+		}
+		if len(val) > 0 {
+			val, extra, ok = parseString(val)
+			if !ok {
+				return nil, errShortRead
+			}
+			if len(extra) > 0 {
+				return nil, fmt.Errorf("ssh: unexpected trailing data after certificate option value")
+			}
+			tups[keyStr] = string(val)
+		} else {
+			tups[keyStr] = ""
+		}
+	}
+	return tups, nil
+}
+
+func parseCert(in []byte, privAlgo string) (*Certificate, error) {
+	nonce, rest, ok := parseString(in)
+	if !ok {
+		return nil, errShortRead
+	}
+
+	key, rest, err := parsePubKey(rest, privAlgo)
+	if err != nil {
+		return nil, err
+	}
+
+	var g genericCertData
+	if err := Unmarshal(rest, &g); err != nil {
+		return nil, err
+	}
+
+	c := &Certificate{
+		Nonce:       nonce,
+		Key:         key,
+		Serial:      g.Serial,
+		CertType:    g.CertType,
+		KeyId:       g.KeyId,
+		ValidAfter:  g.ValidAfter,
+		ValidBefore: g.ValidBefore,
+	}
+
+	for principals := g.ValidPrincipals; len(principals) > 0; {
+		principal, rest, ok := parseString(principals)
+		if !ok {
+			return nil, errShortRead
+		}
+		c.ValidPrincipals = append(c.ValidPrincipals, string(principal))
+		principals = rest
+	}
+
+	c.CriticalOptions, err = parseTuples(g.CriticalOptions)
+	if err != nil {
+		return nil, err
+	}
+	c.Extensions, err = parseTuples(g.Extensions)
+	if err != nil {
+		return nil, err
+	}
+	c.Reserved = g.Reserved
+	k, err := ParsePublicKey(g.SignatureKey)
+	if err != nil {
+		return nil, err
+	}
+
+	c.SignatureKey = k
+	c.Signature, rest, ok = parseSignatureBody(g.Signature)
+	if !ok || len(rest) > 0 {
+		return nil, errors.New("ssh: signature parse error")
+	}
+
+	return c, nil
+}
+
+type openSSHCertSigner struct {
+	pub    *Certificate
+	signer Signer
+}
+
+// NewCertSigner returns a Signer that signs with the given Certificate, whose
+// private key is held by signer. It returns an error if the public key in cert
+// doesn't match the key used by signer.
+func NewCertSigner(cert *Certificate, signer Signer) (Signer, error) {
+	if bytes.Compare(cert.Key.Marshal(), signer.PublicKey().Marshal()) != 0 {
+		return nil, errors.New("ssh: signer and cert have different public key")
+	}
+
+	return &openSSHCertSigner{cert, signer}, nil
+}
+
+func (s *openSSHCertSigner) Sign(rand io.Reader, data []byte) (*Signature, error) {
+	return s.signer.Sign(rand, data)
+}
+
+func (s *openSSHCertSigner) PublicKey() PublicKey {
+	return s.pub
+}
+
+const sourceAddressCriticalOption = "source-address"
+
+// CertChecker does the work of verifying a certificate. Its methods
+// can be plugged into ClientConfig.HostKeyCallback and
+// ServerConfig.PublicKeyCallback. For the CertChecker to work,
+// minimally, the IsAuthority callback should be set.
+type CertChecker struct {
+	// SupportedCriticalOptions lists the CriticalOptions that the
+	// server application layer understands. These are only used
+	// for user certificates.
+	SupportedCriticalOptions []string
+
+	// IsUserAuthority should return true if the key is recognized as an
+	// authority for the given user certificate. This allows for
+	// certificates to be signed by other certificates. This must be set
+	// if this CertChecker will be checking user certificates.
+	IsUserAuthority func(auth PublicKey) bool
+
+	// IsHostAuthority should report whether the key is recognized as
+	// an authority for this host. This allows for certificates to be
+	// signed by other keys, and for those other keys to only be valid
+	// signers for particular hostnames. This must be set if this
+	// CertChecker will be checking host certificates.
+	IsHostAuthority func(auth PublicKey, address string) bool
+
+	// Clock is used for verifying time stamps. If nil, time.Now
+	// is used.
+	Clock func() time.Time
+
+	// UserKeyFallback is called when CertChecker.Authenticate encounters a
+	// public key that is not a certificate. It must implement validation
+	// of user keys or else, if nil, all such keys are rejected.
+	UserKeyFallback func(conn ConnMetadata, key PublicKey) (*Permissions, error)
+
+	// HostKeyFallback is called when CertChecker.CheckHostKey encounters a
+	// public key that is not a certificate. It must implement host key
+	// validation or else, if nil, all such keys are rejected.
+	HostKeyFallback HostKeyCallback
+
+	// IsRevoked is called for each certificate so that revocation checking
+	// can be implemented. It should return true if the given certificate
+	// is revoked and false otherwise. If nil, no certificates are
+	// considered to have been revoked.
+	IsRevoked func(cert *Certificate) bool
+}
+
+// CheckHostKey checks a host key certificate. This method can be
+// plugged into ClientConfig.HostKeyCallback.
+func (c *CertChecker) CheckHostKey(addr string, remote net.Addr, key PublicKey) error {
+	cert, ok := key.(*Certificate)
+	if !ok {
+		if c.HostKeyFallback != nil {
+			return c.HostKeyFallback(addr, remote, key)
+		}
+		return errors.New("ssh: non-certificate host key")
+	}
+	if cert.CertType != HostCert {
+		return fmt.Errorf("ssh: certificate presented as a host key has type %d", cert.CertType)
+	}
+	if !c.IsHostAuthority(cert.SignatureKey, addr) {
+		return fmt.Errorf("ssh: no authorities for hostname: %v", addr)
+	}
+
+	hostname, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return err
+	}
+
+	// Pass hostname only as principal for host certificates (consistent with OpenSSH)
+	return c.CheckCert(hostname, cert)
+}
+
+// Authenticate checks a user certificate. Authenticate can be used as
+// a value for ServerConfig.PublicKeyCallback.
+func (c *CertChecker) Authenticate(conn ConnMetadata, pubKey PublicKey) (*Permissions, error) {
+	cert, ok := pubKey.(*Certificate)
+	if !ok {
+		if c.UserKeyFallback != nil {
+			return c.UserKeyFallback(conn, pubKey)
+		}
+		return nil, errors.New("ssh: normal key pairs not accepted")
+	}
+
+	if cert.CertType != UserCert {
+		return nil, fmt.Errorf("ssh: cert has type %d", cert.CertType)
+	}
+	if !c.IsUserAuthority(cert.SignatureKey) {
+		return nil, fmt.Errorf("ssh: certificate signed by unrecognized authority")
+	}
+
+	if err := c.CheckCert(conn.User(), cert); err != nil {
+		return nil, err
+	}
+
+	return &cert.Permissions, nil
+}
+
+// CheckCert checks CriticalOptions, ValidPrincipals, revocation, timestamp and
+// the signature of the certificate.
+func (c *CertChecker) CheckCert(principal string, cert *Certificate) error {
+	if c.IsRevoked != nil && c.IsRevoked(cert) {
+		return fmt.Errorf("ssh: certicate serial %d revoked", cert.Serial)
+	}
+
+	for opt, _ := range cert.CriticalOptions {
+		// sourceAddressCriticalOption will be enforced by
+		// serverAuthenticate
+		if opt == sourceAddressCriticalOption {
+			continue
+		}
+
+		found := false
+		for _, supp := range c.SupportedCriticalOptions {
+			if supp == opt {
+				found = true
+				break
+			}
+		}
+		if !found {
+			return fmt.Errorf("ssh: unsupported critical option %q in certificate", opt)
+		}
+	}
+
+	if len(cert.ValidPrincipals) > 0 {
+		// By default, certs are valid for all users/hosts.
+		found := false
+		for _, p := range cert.ValidPrincipals {
+			if p == principal {
+				found = true
+				break
+			}
+		}
+		if !found {
+			return fmt.Errorf("ssh: principal %q not in the set of valid principals for given certificate: %q", principal, cert.ValidPrincipals)
+		}
+	}
+
+	clock := c.Clock
+	if clock == nil {
+		clock = time.Now
+	}
+
+	unixNow := clock().Unix()
+	if after := int64(cert.ValidAfter); after < 0 || unixNow < int64(cert.ValidAfter) {
+		return fmt.Errorf("ssh: cert is not yet valid")
+	}
+	if before := int64(cert.ValidBefore); cert.ValidBefore != uint64(CertTimeInfinity) && (unixNow >= before || before < 0) {
+		return fmt.Errorf("ssh: cert has expired")
+	}
+	if err := cert.SignatureKey.Verify(cert.bytesForSigning(), cert.Signature); err != nil {
+		return fmt.Errorf("ssh: certificate signature does not verify")
+	}
+
+	return nil
+}
+
+// SignCert sets c.SignatureKey to the authority's public key and stores a
+// Signature, by authority, in the certificate.
+func (c *Certificate) SignCert(rand io.Reader, authority Signer) error {
+	c.Nonce = make([]byte, 32)
+	if _, err := io.ReadFull(rand, c.Nonce); err != nil {
+		return err
+	}
+	c.SignatureKey = authority.PublicKey()
+
+	sig, err := authority.Sign(rand, c.bytesForSigning())
+	if err != nil {
+		return err
+	}
+	c.Signature = sig
+	return nil
+}
+
+var certAlgoNames = map[string]string{
+	KeyAlgoRSA:      CertAlgoRSAv01,
+	KeyAlgoDSA:      CertAlgoDSAv01,
+	KeyAlgoECDSA256: CertAlgoECDSA256v01,
+	KeyAlgoECDSA384: CertAlgoECDSA384v01,
+	KeyAlgoECDSA521: CertAlgoECDSA521v01,
+	KeyAlgoED25519:  CertAlgoED25519v01,
+}
+
+// certToPrivAlgo returns the underlying algorithm for a certificate algorithm.
+// Panics if a non-certificate algorithm is passed.
+func certToPrivAlgo(algo string) string {
+	for privAlgo, pubAlgo := range certAlgoNames {
+		if pubAlgo == algo {
+			return privAlgo
+		}
+	}
+	panic("unknown cert algorithm")
+}
+
+func (cert *Certificate) bytesForSigning() []byte {
+	c2 := *cert
+	c2.Signature = nil
+	out := c2.Marshal()
+	// Drop trailing signature length.
+	return out[:len(out)-4]
+}
+
+// Marshal serializes c into OpenSSH's wire format. It is part of the
+// PublicKey interface.
+func (c *Certificate) Marshal() []byte {
+	generic := genericCertData{
+		Serial:          c.Serial,
+		CertType:        c.CertType,
+		KeyId:           c.KeyId,
+		ValidPrincipals: marshalStringList(c.ValidPrincipals),
+		ValidAfter:      uint64(c.ValidAfter),
+		ValidBefore:     uint64(c.ValidBefore),
+		CriticalOptions: marshalTuples(c.CriticalOptions),
+		Extensions:      marshalTuples(c.Extensions),
+		Reserved:        c.Reserved,
+		SignatureKey:    c.SignatureKey.Marshal(),
+	}
+	if c.Signature != nil {
+		generic.Signature = Marshal(c.Signature)
+	}
+	genericBytes := Marshal(&generic)
+	keyBytes := c.Key.Marshal()
+	_, keyBytes, _ = parseString(keyBytes)
+	prefix := Marshal(&struct {
+		Name  string
+		Nonce []byte
+		Key   []byte `ssh:"rest"`
+	}{c.Type(), c.Nonce, keyBytes})
+
+	result := make([]byte, 0, len(prefix)+len(genericBytes))
+	result = append(result, prefix...)
+	result = append(result, genericBytes...)
+	return result
+}
+
+// Type returns the key name. It is part of the PublicKey interface.
+func (c *Certificate) Type() string {
+	algo, ok := certAlgoNames[c.Key.Type()]
+	if !ok {
+		panic("unknown cert key type " + c.Key.Type())
+	}
+	return algo
+}
+
+// Verify verifies a signature against the certificate's public
+// key. It is part of the PublicKey interface.
+func (c *Certificate) Verify(data []byte, sig *Signature) error {
+	return c.Key.Verify(data, sig)
+}
+
+func parseSignatureBody(in []byte) (out *Signature, rest []byte, ok bool) {
+	format, in, ok := parseString(in)
+	if !ok {
+		return
+	}
+
+	out = &Signature{
+		Format: string(format),
+	}
+
+	if out.Blob, in, ok = parseString(in); !ok {
+		return
+	}
+
+	return out, in, ok
+}
+
+func parseSignature(in []byte) (out *Signature, rest []byte, ok bool) {
+	sigBytes, rest, ok := parseString(in)
+	if !ok {
+		return
+	}
+
+	out, trailing, ok := parseSignatureBody(sigBytes)
+	if !ok || len(trailing) > 0 {
+		return nil, nil, false
+	}
+	return
+}

vendor/golang.org/x/crypto/ssh/channel.go

@@ -0,0 +1,633 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"sync"
+)
+
+const (
+	minPacketLength = 9
+	// channelMaxPacket contains the maximum number of bytes that will be
+	// sent in a single packet. As per RFC 4253, section 6.1, 32k is also
+	// the minimum.
+	channelMaxPacket = 1 << 15
+	// We follow OpenSSH here.
+	channelWindowSize = 64 * channelMaxPacket
+)
+
+// NewChannel represents an incoming request to a channel. It must either be
+// accepted for use by calling Accept, or rejected by calling Reject.
+type NewChannel interface {
+	// Accept accepts the channel creation request. It returns the Channel
+	// and a Go channel containing SSH requests. The Go channel must be
+	// serviced otherwise the Channel will hang.
+	Accept() (Channel, <-chan *Request, error)
+
+	// Reject rejects the channel creation request. After calling
+	// this, no other methods on the Channel may be called.
+	Reject(reason RejectionReason, message string) error
+
+	// ChannelType returns the type of the channel, as supplied by the
+	// client.
+	ChannelType() string
+
+	// ExtraData returns the arbitrary payload for this channel, as supplied
+	// by the client. This data is specific to the channel type.
+	ExtraData() []byte
+}
+
+// A Channel is an ordered, reliable, flow-controlled, duplex stream
+// that is multiplexed over an SSH connection.
+type Channel interface {
+	// Read reads up to len(data) bytes from the channel.
+	Read(data []byte) (int, error)
+
+	// Write writes len(data) bytes to the channel.
+	Write(data []byte) (int, error)
+
+	// Close signals end of channel use. No data may be sent after this
+	// call.
+	Close() error
+
+	// CloseWrite signals the end of sending in-band
+	// data. Requests may still be sent, and the other side may
+	// still send data
+	CloseWrite() error
+
+	// SendRequest sends a channel request.  If wantReply is true,
+	// it will wait for a reply and return the result as a
+	// boolean, otherwise the return value will be false. Channel
+	// requests are out-of-band messages so they may be sent even
+	// if the data stream is closed or blocked by flow control.
+	// If the channel is closed before a reply is returned, io.EOF
+	// is returned.
+	SendRequest(name string, wantReply bool, payload []byte) (bool, error)
+
+	// Stderr returns an io.ReadWriter that writes to this channel
+	// with the extended data type set to stderr. Stderr may
+	// safely be read and written from a different goroutine than
+	// Read and Write respectively.
+	Stderr() io.ReadWriter
+}
+
+// Request is a request sent outside of the normal stream of
+// data. Requests can either be specific to an SSH channel, or they
+// can be global.
+type Request struct {
+	Type      string
+	WantReply bool
+	Payload   []byte
+
+	ch  *channel
+	mux *mux
+}
+
+// Reply sends a response to a request. It must be called for all requests
+// where WantReply is true and is a no-op otherwise. The payload argument is
+// ignored for replies to channel-specific requests.
+func (r *Request) Reply(ok bool, payload []byte) error {
+	if !r.WantReply {
+		return nil
+	}
+
+	if r.ch == nil {
+		return r.mux.ackRequest(ok, payload)
+	}
+
+	return r.ch.ackRequest(ok)
+}
+
+// RejectionReason is an enumeration used when rejecting channel creation
+// requests. See RFC 4254, section 5.1.
+type RejectionReason uint32
+
+const (
+	Prohibited RejectionReason = iota + 1
+	ConnectionFailed
+	UnknownChannelType
+	ResourceShortage
+)
+
+// String converts the rejection reason to human readable form.
+func (r RejectionReason) String() string {
+	switch r {
+	case Prohibited:
+		return "administratively prohibited"
+	case ConnectionFailed:
+		return "connect failed"
+	case UnknownChannelType:
+		return "unknown channel type"
+	case ResourceShortage:
+		return "resource shortage"
+	}
+	return fmt.Sprintf("unknown reason %d", int(r))
+}
+
+func min(a uint32, b int) uint32 {
+	if a < uint32(b) {
+		return a
+	}
+	return uint32(b)
+}
+
+type channelDirection uint8
+
+const (
+	channelInbound channelDirection = iota
+	channelOutbound
+)
+
+// channel is an implementation of the Channel interface that works
+// with the mux class.
+type channel struct {
+	// R/O after creation
+	chanType          string
+	extraData         []byte
+	localId, remoteId uint32
+
+	// maxIncomingPayload and maxRemotePayload are the maximum
+	// payload sizes of normal and extended data packets for
+	// receiving and sending, respectively. The wire packet will
+	// be 9 or 13 bytes larger (excluding encryption overhead).
+	maxIncomingPayload uint32
+	maxRemotePayload   uint32
+
+	mux *mux
+
+	// decided is set to true if an accept or reject message has been sent
+	// (for outbound channels) or received (for inbound channels).
+	decided bool
+
+	// direction contains either channelOutbound, for channels created
+	// locally, or channelInbound, for channels created by the peer.
+	direction channelDirection
+
+	// Pending internal channel messages.
+	msg chan interface{}
+
+	// Since requests have no ID, there can be only one request
+	// with WantReply=true outstanding.  This lock is held by a
+	// goroutine that has such an outgoing request pending.
+	sentRequestMu sync.Mutex
+
+	incomingRequests chan *Request
+
+	sentEOF bool
+
+	// thread-safe data
+	remoteWin  window
+	pending    *buffer
+	extPending *buffer
+
+	// windowMu protects myWindow, the flow-control window.
+	windowMu sync.Mutex
+	myWindow uint32
+
+	// writeMu serializes calls to mux.conn.writePacket() and
+	// protects sentClose and packetPool. This mutex must be
+	// different from windowMu, as writePacket can block if there
+	// is a key exchange pending.
+	writeMu   sync.Mutex
+	sentClose bool
+
+	// packetPool has a buffer for each extended channel ID to
+	// save allocations during writes.
+	packetPool map[uint32][]byte
+}
+
+// writePacket sends a packet. If the packet is a channel close, it updates
+// sentClose. This method takes the lock c.writeMu.
+func (c *channel) writePacket(packet []byte) error {
+	c.writeMu.Lock()
+	if c.sentClose {
+		c.writeMu.Unlock()
+		return io.EOF
+	}
+	c.sentClose = (packet[0] == msgChannelClose)
+	err := c.mux.conn.writePacket(packet)
+	c.writeMu.Unlock()
+	return err
+}
+
+func (c *channel) sendMessage(msg interface{}) error {
+	if debugMux {
+		log.Printf("send(%d): %#v", c.mux.chanList.offset, msg)
+	}
+
+	p := Marshal(msg)
+	binary.BigEndian.PutUint32(p[1:], c.remoteId)
+	return c.writePacket(p)
+}
+
+// WriteExtended writes data to a specific extended stream. These streams are
+// used, for example, for stderr.
+func (c *channel) WriteExtended(data []byte, extendedCode uint32) (n int, err error) {
+	if c.sentEOF {
+		return 0, io.EOF
+	}
+	// 1 byte message type, 4 bytes remoteId, 4 bytes data length
+	opCode := byte(msgChannelData)
+	headerLength := uint32(9)
+	if extendedCode > 0 {
+		headerLength += 4
+		opCode = msgChannelExtendedData
+	}
+
+	c.writeMu.Lock()
+	packet := c.packetPool[extendedCode]
+	// We don't remove the buffer from packetPool, so
+	// WriteExtended calls from different goroutines will be
+	// flagged as errors by the race detector.
+	c.writeMu.Unlock()
+
+	for len(data) > 0 {
+		space := min(c.maxRemotePayload, len(data))
+		if space, err = c.remoteWin.reserve(space); err != nil {
+			return n, err
+		}
+		if want := headerLength + space; uint32(cap(packet)) < want {
+			packet = make([]byte, want)
+		} else {
+			packet = packet[:want]
+		}
+
+		todo := data[:space]
+
+		packet[0] = opCode
+		binary.BigEndian.PutUint32(packet[1:], c.remoteId)
+		if extendedCode > 0 {
+			binary.BigEndian.PutUint32(packet[5:], uint32(extendedCode))
+		}
+		binary.BigEndian.PutUint32(packet[headerLength-4:], uint32(len(todo)))
+		copy(packet[headerLength:], todo)
+		if err = c.writePacket(packet); err != nil {
+			return n, err
+		}
+
+		n += len(todo)
+		data = data[len(todo):]
+	}
+
+	c.writeMu.Lock()
+	c.packetPool[extendedCode] = packet
+	c.writeMu.Unlock()
+
+	return n, err
+}
+
+func (c *channel) handleData(packet []byte) error {
+	headerLen := 9
+	isExtendedData := packet[0] == msgChannelExtendedData
+	if isExtendedData {
+		headerLen = 13
+	}
+	if len(packet) < headerLen {
+		// malformed data packet
+		return parseError(packet[0])
+	}
+
+	var extended uint32
+	if isExtendedData {
+		extended = binary.BigEndian.Uint32(packet[5:])
+	}
+
+	length := binary.BigEndian.Uint32(packet[headerLen-4 : headerLen])
+	if length == 0 {
+		return nil
+	}
+	if length > c.maxIncomingPayload {
+		// TODO(hanwen): should send Disconnect?
+		return errors.New("ssh: incoming packet exceeds maximum payload size")
+	}
+
+	data := packet[headerLen:]
+	if length != uint32(len(data)) {
+		return errors.New("ssh: wrong packet length")
+	}
+
+	c.windowMu.Lock()
+	if c.myWindow < length {
+		c.windowMu.Unlock()
+		// TODO(hanwen): should send Disconnect with reason?
+		return errors.New("ssh: remote side wrote too much")
+	}
+	c.myWindow -= length
+	c.windowMu.Unlock()
+
+	if extended == 1 {
+		c.extPending.write(data)
+	} else if extended > 0 {
+		// discard other extended data.
+	} else {
+		c.pending.write(data)
+	}
+	return nil
+}
+
+func (c *channel) adjustWindow(n uint32) error {
+	c.windowMu.Lock()
+	// Since myWindow is managed on our side, and can never exceed
+	// the initial window setting, we don't worry about overflow.
+	c.myWindow += uint32(n)
+	c.windowMu.Unlock()
+	return c.sendMessage(windowAdjustMsg{
+		AdditionalBytes: uint32(n),
+	})
+}
+
+func (c *channel) ReadExtended(data []byte, extended uint32) (n int, err error) {
+	switch extended {
+	case 1:
+		n, err = c.extPending.Read(data)
+	case 0:
+		n, err = c.pending.Read(data)
+	default:
+		return 0, fmt.Errorf("ssh: extended code %d unimplemented", extended)
+	}
+
+	if n > 0 {
+		err = c.adjustWindow(uint32(n))
+		// sendWindowAdjust can return io.EOF if the remote
+		// peer has closed the connection, however we want to
+		// defer forwarding io.EOF to the caller of Read until
+		// the buffer has been drained.
+		if n > 0 && err == io.EOF {
+			err = nil
+		}
+	}
+
+	return n, err
+}
+
+func (c *channel) close() {
+	c.pending.eof()
+	c.extPending.eof()
+	close(c.msg)
+	close(c.incomingRequests)
+	c.writeMu.Lock()
+	// This is not necessary for a normal channel teardown, but if
+	// there was another error, it is.
+	c.sentClose = true
+	c.writeMu.Unlock()
+	// Unblock writers.
+	c.remoteWin.close()
+}
+
+// responseMessageReceived is called when a success or failure message is
+// received on a channel to check that such a message is reasonable for the
+// given channel.
+func (c *channel) responseMessageReceived() error {
+	if c.direction == channelInbound {
+		return errors.New("ssh: channel response message received on inbound channel")
+	}
+	if c.decided {
+		return errors.New("ssh: duplicate response received for channel")
+	}
+	c.decided = true
+	return nil
+}
+
+func (c *channel) handlePacket(packet []byte) error {
+	switch packet[0] {
+	case msgChannelData, msgChannelExtendedData:
+		return c.handleData(packet)
+	case msgChannelClose:
+		c.sendMessage(channelCloseMsg{PeersId: c.remoteId})
+		c.mux.chanList.remove(c.localId)
+		c.close()
+		return nil
+	case msgChannelEOF:
+		// RFC 4254 is mute on how EOF affects dataExt messages but
+		// it is logical to signal EOF at the same time.
+		c.extPending.eof()
+		c.pending.eof()
+		return nil
+	}
+
+	decoded, err := decode(packet)
+	if err != nil {
+		return err
+	}
+
+	switch msg := decoded.(type) {
+	case *channelOpenFailureMsg:
+		if err := c.responseMessageReceived(); err != nil {
+			return err
+		}
+		c.mux.chanList.remove(msg.PeersId)
+		c.msg <- msg
+	case *channelOpenConfirmMsg:
+		if err := c.responseMessageReceived(); err != nil {
+			return err
+		}
+		if msg.MaxPacketSize < minPacketLength || msg.MaxPacketSize > 1<<31 {
+			return fmt.Errorf("ssh: invalid MaxPacketSize %d from peer", msg.MaxPacketSize)
+		}
+		c.remoteId = msg.MyId
+		c.maxRemotePayload = msg.MaxPacketSize
+		c.remoteWin.add(msg.MyWindow)
+		c.msg <- msg
+	case *windowAdjustMsg:
+		if !c.remoteWin.add(msg.AdditionalBytes) {
+			return fmt.Errorf("ssh: invalid window update for %d bytes", msg.AdditionalBytes)
+		}
+	case *channelRequestMsg:
+		req := Request{
+			Type:      msg.Request,
+			WantReply: msg.WantReply,
+			Payload:   msg.RequestSpecificData,
+			ch:        c,
+		}
+
+		c.incomingRequests <- &req
+	default:
+		c.msg <- msg
+	}
+	return nil
+}
+
+func (m *mux) newChannel(chanType string, direction channelDirection, extraData []byte) *channel {
+	ch := &channel{
+		remoteWin:        window{Cond: newCond()},
+		myWindow:         channelWindowSize,
+		pending:          newBuffer(),
+		extPending:       newBuffer(),
+		direction:        direction,
+		incomingRequests: make(chan *Request, chanSize),
+		msg:              make(chan interface{}, chanSize),
+		chanType:         chanType,
+		extraData:        extraData,
+		mux:              m,
+		packetPool:       make(map[uint32][]byte),
+	}
+	ch.localId = m.chanList.add(ch)
+	return ch
+}
+
+var errUndecided = errors.New("ssh: must Accept or Reject channel")
+var errDecidedAlready = errors.New("ssh: can call Accept or Reject only once")
+
+type extChannel struct {
+	code uint32
+	ch   *channel
+}
+
+func (e *extChannel) Write(data []byte) (n int, err error) {
+	return e.ch.WriteExtended(data, e.code)
+}
+
+func (e *extChannel) Read(data []byte) (n int, err error) {
+	return e.ch.ReadExtended(data, e.code)
+}
+
+func (c *channel) Accept() (Channel, <-chan *Request, error) {
+	if c.decided {
+		return nil, nil, errDecidedAlready
+	}
+	c.maxIncomingPayload = channelMaxPacket
+	confirm := channelOpenConfirmMsg{
+		PeersId:       c.remoteId,
+		MyId:          c.localId,
+		MyWindow:      c.myWindow,
+		MaxPacketSize: c.maxIncomingPayload,
+	}
+	c.decided = true
+	if err := c.sendMessage(confirm); err != nil {
+		return nil, nil, err
+	}
+
+	return c, c.incomingRequests, nil
+}
+
+func (ch *channel) Reject(reason RejectionReason, message string) error {
+	if ch.decided {
+		return errDecidedAlready
+	}
+	reject := channelOpenFailureMsg{
+		PeersId:  ch.remoteId,
+		Reason:   reason,
+		Message:  message,
+		Language: "en",
+	}
+	ch.decided = true
+	return ch.sendMessage(reject)
+}
+
+func (ch *channel) Read(data []byte) (int, error) {
+	if !ch.decided {
+		return 0, errUndecided
+	}
+	return ch.ReadExtended(data, 0)
+}
+
+func (ch *channel) Write(data []byte) (int, error) {
+	if !ch.decided {
+		return 0, errUndecided
+	}
+	return ch.WriteExtended(data, 0)
+}
+
+func (ch *channel) CloseWrite() error {
+	if !ch.decided {
+		return errUndecided
+	}
+	ch.sentEOF = true
+	return ch.sendMessage(channelEOFMsg{
+		PeersId: ch.remoteId})
+}
+
+func (ch *channel) Close() error {
+	if !ch.decided {
+		return errUndecided
+	}
+
+	return ch.sendMessage(channelCloseMsg{
+		PeersId: ch.remoteId})
+}
+
+// Extended returns an io.ReadWriter that sends and receives data on the given,
+// SSH extended stream. Such streams are used, for example, for stderr.
+func (ch *channel) Extended(code uint32) io.ReadWriter {
+	if !ch.decided {
+		return nil
+	}
+	return &extChannel{code, ch}
+}
+
+func (ch *channel) Stderr() io.ReadWriter {
+	return ch.Extended(1)
+}
+
+func (ch *channel) SendRequest(name string, wantReply bool, payload []byte) (bool, error) {
+	if !ch.decided {
+		return false, errUndecided
+	}
+
+	if wantReply {
+		ch.sentRequestMu.Lock()
+		defer ch.sentRequestMu.Unlock()
+	}
+
+	msg := channelRequestMsg{
+		PeersId:             ch.remoteId,
+		Request:             name,
+		WantReply:           wantReply,
+		RequestSpecificData: payload,
+	}
+
+	if err := ch.sendMessage(msg); err != nil {
+		return false, err
+	}
+
+	if wantReply {
+		m, ok := (<-ch.msg)
+		if !ok {
+			return false, io.EOF
+		}
+		switch m.(type) {
+		case *channelRequestFailureMsg:
+			return false, nil
+		case *channelRequestSuccessMsg:
+			return true, nil
+		default:
+			return false, fmt.Errorf("ssh: unexpected response to channel request: %#v", m)
+		}
+	}
+
+	return false, nil
+}
+
+// ackRequest either sends an ack or nack to the channel request.
+func (ch *channel) ackRequest(ok bool) error {
+	if !ch.decided {
+		return errUndecided
+	}
+
+	var msg interface{}
+	if !ok {
+		msg = channelRequestFailureMsg{
+			PeersId: ch.remoteId,
+		}
+	} else {
+		msg = channelRequestSuccessMsg{
+			PeersId: ch.remoteId,
+		}
+	}
+	return ch.sendMessage(msg)
+}
+
+func (ch *channel) ChannelType() string {
+	return ch.chanType
+}
+
+func (ch *channel) ExtraData() []byte {
+	return ch.extraData
+}

vendor/golang.org/x/crypto/ssh/cipher.go

@@ -0,0 +1,629 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/des"
+	"crypto/rc4"
+	"crypto/subtle"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"hash"
+	"io"
+	"io/ioutil"
+)
+
+const (
+	packetSizeMultiple = 16 // TODO(huin) this should be determined by the cipher.
+
+	// RFC 4253 section 6.1 defines a minimum packet size of 32768 that implementations
+	// MUST be able to process (plus a few more kilobytes for padding and mac). The RFC
+	// indicates implementations SHOULD be able to handle larger packet sizes, but then
+	// waffles on about reasonable limits.
+	//
+	// OpenSSH caps their maxPacket at 256kB so we choose to do
+	// the same. maxPacket is also used to ensure that uint32
+	// length fields do not overflow, so it should remain well
+	// below 4G.
+	maxPacket = 256 * 1024
+)
+
+// noneCipher implements cipher.Stream and provides no encryption. It is used
+// by the transport before the first key-exchange.
+type noneCipher struct{}
+
+func (c noneCipher) XORKeyStream(dst, src []byte) {
+	copy(dst, src)
+}
+
+func newAESCTR(key, iv []byte) (cipher.Stream, error) {
+	c, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	return cipher.NewCTR(c, iv), nil
+}
+
+func newRC4(key, iv []byte) (cipher.Stream, error) {
+	return rc4.NewCipher(key)
+}
+
+type streamCipherMode struct {
+	keySize    int
+	ivSize     int
+	skip       int
+	createFunc func(key, iv []byte) (cipher.Stream, error)
+}
+
+func (c *streamCipherMode) createStream(key, iv []byte) (cipher.Stream, error) {
+	if len(key) < c.keySize {
+		panic("ssh: key length too small for cipher")
+	}
+	if len(iv) < c.ivSize {
+		panic("ssh: iv too small for cipher")
+	}
+
+	stream, err := c.createFunc(key[:c.keySize], iv[:c.ivSize])
+	if err != nil {
+		return nil, err
+	}
+
+	var streamDump []byte
+	if c.skip > 0 {
+		streamDump = make([]byte, 512)
+	}
+
+	for remainingToDump := c.skip; remainingToDump > 0; {
+		dumpThisTime := remainingToDump
+		if dumpThisTime > len(streamDump) {
+			dumpThisTime = len(streamDump)
+		}
+		stream.XORKeyStream(streamDump[:dumpThisTime], streamDump[:dumpThisTime])
+		remainingToDump -= dumpThisTime
+	}
+
+	return stream, nil
+}
+
+// cipherModes documents properties of supported ciphers. Ciphers not included
+// are not supported and will not be negotiated, even if explicitly requested in
+// ClientConfig.Crypto.Ciphers.
+var cipherModes = map[string]*streamCipherMode{
+	// Ciphers from RFC4344, which introduced many CTR-based ciphers. Algorithms
+	// are defined in the order specified in the RFC.
+	"aes128-ctr": {16, aes.BlockSize, 0, newAESCTR},
+	"aes192-ctr": {24, aes.BlockSize, 0, newAESCTR},
+	"aes256-ctr": {32, aes.BlockSize, 0, newAESCTR},
+
+	// Ciphers from RFC4345, which introduces security-improved arcfour ciphers.
+	// They are defined in the order specified in the RFC.
+	"arcfour128": {16, 0, 1536, newRC4},
+	"arcfour256": {32, 0, 1536, newRC4},
+
+	// Cipher defined in RFC 4253, which describes SSH Transport Layer Protocol.
+	// Note that this cipher is not safe, as stated in RFC 4253: "Arcfour (and
+	// RC4) has problems with weak keys, and should be used with caution."
+	// RFC4345 introduces improved versions of Arcfour.
+	"arcfour": {16, 0, 0, newRC4},
+
+	// AES-GCM is not a stream cipher, so it is constructed with a
+	// special case. If we add any more non-stream ciphers, we
+	// should invest a cleaner way to do this.
+	gcmCipherID: {16, 12, 0, nil},
+
+	// CBC mode is insecure and so is not included in the default config.
+	// (See http://www.isg.rhul.ac.uk/~kp/SandPfinal.pdf). If absolutely
+	// needed, it's possible to specify a custom Config to enable it.
+	// You should expect that an active attacker can recover plaintext if
+	// you do.
+	aes128cbcID: {16, aes.BlockSize, 0, nil},
+
+	// 3des-cbc is insecure and is disabled by default.
+	tripledescbcID: {24, des.BlockSize, 0, nil},
+}
+
+// prefixLen is the length of the packet prefix that contains the packet length
+// and number of padding bytes.
+const prefixLen = 5
+
+// streamPacketCipher is a packetCipher using a stream cipher.
+type streamPacketCipher struct {
+	mac    hash.Hash
+	cipher cipher.Stream
+	etm    bool
+
+	// The following members are to avoid per-packet allocations.
+	prefix      [prefixLen]byte
+	seqNumBytes [4]byte
+	padding     [2 * packetSizeMultiple]byte
+	packetData  []byte
+	macResult   []byte
+}
+
+// readPacket reads and decrypt a single packet from the reader argument.
+func (s *streamPacketCipher) readPacket(seqNum uint32, r io.Reader) ([]byte, error) {
+	if _, err := io.ReadFull(r, s.prefix[:]); err != nil {
+		return nil, err
+	}
+
+	var encryptedPaddingLength [1]byte
+	if s.mac != nil && s.etm {
+		copy(encryptedPaddingLength[:], s.prefix[4:5])
+		s.cipher.XORKeyStream(s.prefix[4:5], s.prefix[4:5])
+	} else {
+		s.cipher.XORKeyStream(s.prefix[:], s.prefix[:])
+	}
+
+	length := binary.BigEndian.Uint32(s.prefix[0:4])
+	paddingLength := uint32(s.prefix[4])
+
+	var macSize uint32
+	if s.mac != nil {
+		s.mac.Reset()
+		binary.BigEndian.PutUint32(s.seqNumBytes[:], seqNum)
+		s.mac.Write(s.seqNumBytes[:])
+		if s.etm {
+			s.mac.Write(s.prefix[:4])
+			s.mac.Write(encryptedPaddingLength[:])
+		} else {
+			s.mac.Write(s.prefix[:])
+		}
+		macSize = uint32(s.mac.Size())
+	}
+
+	if length <= paddingLength+1 {
+		return nil, errors.New("ssh: invalid packet length, packet too small")
+	}
+
+	if length > maxPacket {
+		return nil, errors.New("ssh: invalid packet length, packet too large")
+	}
+
+	// the maxPacket check above ensures that length-1+macSize
+	// does not overflow.
+	if uint32(cap(s.packetData)) < length-1+macSize {
+		s.packetData = make([]byte, length-1+macSize)
+	} else {
+		s.packetData = s.packetData[:length-1+macSize]
+	}
+
+	if _, err := io.ReadFull(r, s.packetData); err != nil {
+		return nil, err
+	}
+	mac := s.packetData[length-1:]
+	data := s.packetData[:length-1]
+
+	if s.mac != nil && s.etm {
+		s.mac.Write(data)
+	}
+
+	s.cipher.XORKeyStream(data, data)
+
+	if s.mac != nil {
+		if !s.etm {
+			s.mac.Write(data)
+		}
+		s.macResult = s.mac.Sum(s.macResult[:0])
+		if subtle.ConstantTimeCompare(s.macResult, mac) != 1 {
+			return nil, errors.New("ssh: MAC failure")
+		}
+	}
+
+	return s.packetData[:length-paddingLength-1], nil
+}
+
+// writePacket encrypts and sends a packet of data to the writer argument
+func (s *streamPacketCipher) writePacket(seqNum uint32, w io.Writer, rand io.Reader, packet []byte) error {
+	if len(packet) > maxPacket {
+		return errors.New("ssh: packet too large")
+	}
+
+	aadlen := 0
+	if s.mac != nil && s.etm {
+		// packet length is not encrypted for EtM modes
+		aadlen = 4
+	}
+
+	paddingLength := packetSizeMultiple - (prefixLen+len(packet)-aadlen)%packetSizeMultiple
+	if paddingLength < 4 {
+		paddingLength += packetSizeMultiple
+	}
+
+	length := len(packet) + 1 + paddingLength
+	binary.BigEndian.PutUint32(s.prefix[:], uint32(length))
+	s.prefix[4] = byte(paddingLength)
+	padding := s.padding[:paddingLength]
+	if _, err := io.ReadFull(rand, padding); err != nil {
+		return err
+	}
+
+	if s.mac != nil {
+		s.mac.Reset()
+		binary.BigEndian.PutUint32(s.seqNumBytes[:], seqNum)
+		s.mac.Write(s.seqNumBytes[:])
+
+		if s.etm {
+			// For EtM algorithms, the packet length must stay unencrypted,
+			// but the following data (padding length) must be encrypted
+			s.cipher.XORKeyStream(s.prefix[4:5], s.prefix[4:5])
+		}
+
+		s.mac.Write(s.prefix[:])
+
+		if !s.etm {
+			// For non-EtM algorithms, the algorithm is applied on unencrypted data
+			s.mac.Write(packet)
+			s.mac.Write(padding)
+		}
+	}
+
+	if !(s.mac != nil && s.etm) {
+		// For EtM algorithms, the padding length has already been encrypted
+		// and the packet length must remain unencrypted
+		s.cipher.XORKeyStream(s.prefix[:], s.prefix[:])
+	}
+
+	s.cipher.XORKeyStream(packet, packet)
+	s.cipher.XORKeyStream(padding, padding)
+
+	if s.mac != nil && s.etm {
+		// For EtM algorithms, packet and padding must be encrypted
+		s.mac.Write(packet)
+		s.mac.Write(padding)
+	}
+
+	if _, err := w.Write(s.prefix[:]); err != nil {
+		return err
+	}
+	if _, err := w.Write(packet); err != nil {
+		return err
+	}
+	if _, err := w.Write(padding); err != nil {
+		return err
+	}
+
+	if s.mac != nil {
+		s.macResult = s.mac.Sum(s.macResult[:0])
+		if _, err := w.Write(s.macResult); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+type gcmCipher struct {
+	aead   cipher.AEAD
+	prefix [4]byte
+	iv     []byte
+	buf    []byte
+}
+
+func newGCMCipher(iv, key []byte) (packetCipher, error) {
+	c, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	aead, err := cipher.NewGCM(c)
+	if err != nil {
+		return nil, err
+	}
+
+	return &gcmCipher{
+		aead: aead,
+		iv:   iv,
+	}, nil
+}
+
+const gcmTagSize = 16
+
+func (c *gcmCipher) writePacket(seqNum uint32, w io.Writer, rand io.Reader, packet []byte) error {
+	// Pad out to multiple of 16 bytes. This is different from the
+	// stream cipher because that encrypts the length too.
+	padding := byte(packetSizeMultiple - (1+len(packet))%packetSizeMultiple)
+	if padding < 4 {
+		padding += packetSizeMultiple
+	}
+
+	length := uint32(len(packet) + int(padding) + 1)
+	binary.BigEndian.PutUint32(c.prefix[:], length)
+	if _, err := w.Write(c.prefix[:]); err != nil {
+		return err
+	}
+
+	if cap(c.buf) < int(length) {
+		c.buf = make([]byte, length)
+	} else {
+		c.buf = c.buf[:length]
+	}
+
+	c.buf[0] = padding
+	copy(c.buf[1:], packet)
+	if _, err := io.ReadFull(rand, c.buf[1+len(packet):]); err != nil {
+		return err
+	}
+	c.buf = c.aead.Seal(c.buf[:0], c.iv, c.buf, c.prefix[:])
+	if _, err := w.Write(c.buf); err != nil {
+		return err
+	}
+	c.incIV()
+
+	return nil
+}
+
+func (c *gcmCipher) incIV() {
+	for i := 4 + 7; i >= 4; i-- {
+		c.iv[i]++
+		if c.iv[i] != 0 {
+			break
+		}
+	}
+}
+
+func (c *gcmCipher) readPacket(seqNum uint32, r io.Reader) ([]byte, error) {
+	if _, err := io.ReadFull(r, c.prefix[:]); err != nil {
+		return nil, err
+	}
+	length := binary.BigEndian.Uint32(c.prefix[:])
+	if length > maxPacket {
+		return nil, errors.New("ssh: max packet length exceeded.")
+	}
+
+	if cap(c.buf) < int(length+gcmTagSize) {
+		c.buf = make([]byte, length+gcmTagSize)
+	} else {
+		c.buf = c.buf[:length+gcmTagSize]
+	}
+
+	if _, err := io.ReadFull(r, c.buf); err != nil {
+		return nil, err
+	}
+
+	plain, err := c.aead.Open(c.buf[:0], c.iv, c.buf, c.prefix[:])
+	if err != nil {
+		return nil, err
+	}
+	c.incIV()
+
+	padding := plain[0]
+	if padding < 4 {
+		// padding is a byte, so it automatically satisfies
+		// the maximum size, which is 255.
+		return nil, fmt.Errorf("ssh: illegal padding %d", padding)
+	}
+
+	if int(padding+1) >= len(plain) {
+		return nil, fmt.Errorf("ssh: padding %d too large", padding)
+	}
+	plain = plain[1 : length-uint32(padding)]
+	return plain, nil
+}
+
+// cbcCipher implements aes128-cbc cipher defined in RFC 4253 section 6.1
+type cbcCipher struct {
+	mac       hash.Hash
+	macSize   uint32
+	decrypter cipher.BlockMode
+	encrypter cipher.BlockMode
+
+	// The following members are to avoid per-packet allocations.
+	seqNumBytes [4]byte
+	packetData  []byte
+	macResult   []byte
+
+	// Amount of data we should still read to hide which
+	// verification error triggered.
+	oracleCamouflage uint32
+}
+
+func newCBCCipher(c cipher.Block, iv, key, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
+	cbc := &cbcCipher{
+		mac:        macModes[algs.MAC].new(macKey),
+		decrypter:  cipher.NewCBCDecrypter(c, iv),
+		encrypter:  cipher.NewCBCEncrypter(c, iv),
+		packetData: make([]byte, 1024),
+	}
+	if cbc.mac != nil {
+		cbc.macSize = uint32(cbc.mac.Size())
+	}
+
+	return cbc, nil
+}
+
+func newAESCBCCipher(iv, key, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
+	c, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	cbc, err := newCBCCipher(c, iv, key, macKey, algs)
+	if err != nil {
+		return nil, err
+	}
+
+	return cbc, nil
+}
+
+func newTripleDESCBCCipher(iv, key, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
+	c, err := des.NewTripleDESCipher(key)
+	if err != nil {
+		return nil, err
+	}
+
+	cbc, err := newCBCCipher(c, iv, key, macKey, algs)
+	if err != nil {
+		return nil, err
+	}
+
+	return cbc, nil
+}
+
+func maxUInt32(a, b int) uint32 {
+	if a > b {
+		return uint32(a)
+	}
+	return uint32(b)
+}
+
+const (
+	cbcMinPacketSizeMultiple = 8
+	cbcMinPacketSize         = 16
+	cbcMinPaddingSize        = 4
+)
+
+// cbcError represents a verification error that may leak information.
+type cbcError string
+
+func (e cbcError) Error() string { return string(e) }
+
+func (c *cbcCipher) readPacket(seqNum uint32, r io.Reader) ([]byte, error) {
+	p, err := c.readPacketLeaky(seqNum, r)
+	if err != nil {
+		if _, ok := err.(cbcError); ok {
+			// Verification error: read a fixed amount of
+			// data, to make distinguishing between
+			// failing MAC and failing length check more
+			// difficult.
+			io.CopyN(ioutil.Discard, r, int64(c.oracleCamouflage))
+		}
+	}
+	return p, err
+}
+
+func (c *cbcCipher) readPacketLeaky(seqNum uint32, r io.Reader) ([]byte, error) {
+	blockSize := c.decrypter.BlockSize()
+
+	// Read the header, which will include some of the subsequent data in the
+	// case of block ciphers - this is copied back to the payload later.
+	// How many bytes of payload/padding will be read with this first read.
+	firstBlockLength := uint32((prefixLen + blockSize - 1) / blockSize * blockSize)
+	firstBlock := c.packetData[:firstBlockLength]
+	if _, err := io.ReadFull(r, firstBlock); err != nil {
+		return nil, err
+	}
+
+	c.oracleCamouflage = maxPacket + 4 + c.macSize - firstBlockLength
+
+	c.decrypter.CryptBlocks(firstBlock, firstBlock)
+	length := binary.BigEndian.Uint32(firstBlock[:4])
+	if length > maxPacket {
+		return nil, cbcError("ssh: packet too large")
+	}
+	if length+4 < maxUInt32(cbcMinPacketSize, blockSize) {
+		// The minimum size of a packet is 16 (or the cipher block size, whichever
+		// is larger) bytes.
+		return nil, cbcError("ssh: packet too small")
+	}
+	// The length of the packet (including the length field but not the MAC) must
+	// be a multiple of the block size or 8, whichever is larger.
+	if (length+4)%maxUInt32(cbcMinPacketSizeMultiple, blockSize) != 0 {
+		return nil, cbcError("ssh: invalid packet length multiple")
+	}
+
+	paddingLength := uint32(firstBlock[4])
+	if paddingLength < cbcMinPaddingSize || length <= paddingLength+1 {
+		return nil, cbcError("ssh: invalid packet length")
+	}
+
+	// Positions within the c.packetData buffer:
+	macStart := 4 + length
+	paddingStart := macStart - paddingLength
+
+	// Entire packet size, starting before length, ending at end of mac.
+	entirePacketSize := macStart + c.macSize
+
+	// Ensure c.packetData is large enough for the entire packet data.
+	if uint32(cap(c.packetData)) < entirePacketSize {
+		// Still need to upsize and copy, but this should be rare at runtime, only
+		// on upsizing the packetData buffer.
+		c.packetData = make([]byte, entirePacketSize)
+		copy(c.packetData, firstBlock)
+	} else {
+		c.packetData = c.packetData[:entirePacketSize]
+	}
+
+	if n, err := io.ReadFull(r, c.packetData[firstBlockLength:]); err != nil {
+		return nil, err
+	} else {
+		c.oracleCamouflage -= uint32(n)
+	}
+
+	remainingCrypted := c.packetData[firstBlockLength:macStart]
+	c.decrypter.CryptBlocks(remainingCrypted, remainingCrypted)
+
+	mac := c.packetData[macStart:]
+	if c.mac != nil {
+		c.mac.Reset()
+		binary.BigEndian.PutUint32(c.seqNumBytes[:], seqNum)
+		c.mac.Write(c.seqNumBytes[:])
+		c.mac.Write(c.packetData[:macStart])
+		c.macResult = c.mac.Sum(c.macResult[:0])
+		if subtle.ConstantTimeCompare(c.macResult, mac) != 1 {
+			return nil, cbcError("ssh: MAC failure")
+		}
+	}
+
+	return c.packetData[prefixLen:paddingStart], nil
+}
+
+func (c *cbcCipher) writePacket(seqNum uint32, w io.Writer, rand io.Reader, packet []byte) error {
+	effectiveBlockSize := maxUInt32(cbcMinPacketSizeMultiple, c.encrypter.BlockSize())
+
+	// Length of encrypted portion of the packet (header, payload, padding).
+	// Enforce minimum padding and packet size.
+	encLength := maxUInt32(prefixLen+len(packet)+cbcMinPaddingSize, cbcMinPaddingSize)
+	// Enforce block size.
+	encLength = (encLength + effectiveBlockSize - 1) / effectiveBlockSize * effectiveBlockSize
+
+	length := encLength - 4
+	paddingLength := int(length) - (1 + len(packet))
+
+	// Overall buffer contains: header, payload, padding, mac.
+	// Space for the MAC is reserved in the capacity but not the slice length.
+	bufferSize := encLength + c.macSize
+	if uint32(cap(c.packetData)) < bufferSize {
+		c.packetData = make([]byte, encLength, bufferSize)
+	} else {
+		c.packetData = c.packetData[:encLength]
+	}
+
+	p := c.packetData
+
+	// Packet header.
+	binary.BigEndian.PutUint32(p, length)
+	p = p[4:]
+	p[0] = byte(paddingLength)
+
+	// Payload.
+	p = p[1:]
+	copy(p, packet)
+
+	// Padding.
+	p = p[len(packet):]
+	if _, err := io.ReadFull(rand, p); err != nil {
+		return err
+	}
+
+	if c.mac != nil {
+		c.mac.Reset()
+		binary.BigEndian.PutUint32(c.seqNumBytes[:], seqNum)
+		c.mac.Write(c.seqNumBytes[:])
+		c.mac.Write(c.packetData)
+		// The MAC is now appended into the capacity reserved for it earlier.
+		c.packetData = c.mac.Sum(c.packetData)
+	}
+
+	c.encrypter.CryptBlocks(c.packetData[:encLength], c.packetData[:encLength])
+
+	if _, err := w.Write(c.packetData); err != nil {
+		return err
+	}
+
+	return nil
+}

vendor/golang.org/x/crypto/ssh/client.go

@@ -0,0 +1,278 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"net"
+	"os"
+	"sync"
+	"time"
+)
+
+// Client implements a traditional SSH client that supports shells,
+// subprocesses, TCP port/streamlocal forwarding and tunneled dialing.
+type Client struct {
+	Conn
+
+	forwards        forwardList // forwarded tcpip connections from the remote side
+	mu              sync.Mutex
+	channelHandlers map[string]chan NewChannel
+}
+
+// HandleChannelOpen returns a channel on which NewChannel requests
+// for the given type are sent. If the type already is being handled,
+// nil is returned. The channel is closed when the connection is closed.
+func (c *Client) HandleChannelOpen(channelType string) <-chan NewChannel {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.channelHandlers == nil {
+		// The SSH channel has been closed.
+		c := make(chan NewChannel)
+		close(c)
+		return c
+	}
+
+	ch := c.channelHandlers[channelType]
+	if ch != nil {
+		return nil
+	}
+
+	ch = make(chan NewChannel, chanSize)
+	c.channelHandlers[channelType] = ch
+	return ch
+}
+
+// NewClient creates a Client on top of the given connection.
+func NewClient(c Conn, chans <-chan NewChannel, reqs <-chan *Request) *Client {
+	conn := &Client{
+		Conn:            c,
+		channelHandlers: make(map[string]chan NewChannel, 1),
+	}
+
+	go conn.handleGlobalRequests(reqs)
+	go conn.handleChannelOpens(chans)
+	go func() {
+		conn.Wait()
+		conn.forwards.closeAll()
+	}()
+	go conn.forwards.handleChannels(conn.HandleChannelOpen("forwarded-tcpip"))
+	go conn.forwards.handleChannels(conn.HandleChannelOpen("forwarded-streamlocal@openssh.com"))
+	return conn
+}
+
+// NewClientConn establishes an authenticated SSH connection using c
+// as the underlying transport.  The Request and NewChannel channels
+// must be serviced or the connection will hang.
+func NewClientConn(c net.Conn, addr string, config *ClientConfig) (Conn, <-chan NewChannel, <-chan *Request, error) {
+	fullConf := *config
+	fullConf.SetDefaults()
+	if fullConf.HostKeyCallback == nil {
+		c.Close()
+		return nil, nil, nil, errors.New("ssh: must specify HostKeyCallback")
+	}
+
+	conn := &connection{
+		sshConn: sshConn{conn: c},
+	}
+
+	if err := conn.clientHandshake(addr, &fullConf); err != nil {
+		c.Close()
+		return nil, nil, nil, fmt.Errorf("ssh: handshake failed: %v", err)
+	}
+	conn.mux = newMux(conn.transport)
+	return conn, conn.mux.incomingChannels, conn.mux.incomingRequests, nil
+}
+
+// clientHandshake performs the client side key exchange. See RFC 4253 Section
+// 7.
+func (c *connection) clientHandshake(dialAddress string, config *ClientConfig) error {
+	if config.ClientVersion != "" {
+		c.clientVersion = []byte(config.ClientVersion)
+	} else {
+		c.clientVersion = []byte(packageVersion)
+	}
+	var err error
+	c.serverVersion, err = exchangeVersions(c.sshConn.conn, c.clientVersion)
+	if err != nil {
+		return err
+	}
+
+	c.transport = newClientTransport(
+		newTransport(c.sshConn.conn, config.Rand, true /* is client */),
+		c.clientVersion, c.serverVersion, config, dialAddress, c.sshConn.RemoteAddr())
+	if err := c.transport.waitSession(); err != nil {
+		return err
+	}
+
+	c.sessionID = c.transport.getSessionID()
+	return c.clientAuthenticate(config)
+}
+
+// verifyHostKeySignature verifies the host key obtained in the key
+// exchange.
+func verifyHostKeySignature(hostKey PublicKey, result *kexResult) error {
+	sig, rest, ok := parseSignatureBody(result.Signature)
+	if len(rest) > 0 || !ok {
+		return errors.New("ssh: signature parse error")
+	}
+
+	return hostKey.Verify(result.H, sig)
+}
+
+// NewSession opens a new Session for this client. (A session is a remote
+// execution of a program.)
+func (c *Client) NewSession() (*Session, error) {
+	ch, in, err := c.OpenChannel("session", nil)
+	if err != nil {
+		return nil, err
+	}
+	return newSession(ch, in)
+}
+
+func (c *Client) handleGlobalRequests(incoming <-chan *Request) {
+	for r := range incoming {
+		// This handles keepalive messages and matches
+		// the behaviour of OpenSSH.
+		r.Reply(false, nil)
+	}
+}
+
+// handleChannelOpens channel open messages from the remote side.
+func (c *Client) handleChannelOpens(in <-chan NewChannel) {
+	for ch := range in {
+		c.mu.Lock()
+		handler := c.channelHandlers[ch.ChannelType()]
+		c.mu.Unlock()
+
+		if handler != nil {
+			handler <- ch
+		} else {
+			ch.Reject(UnknownChannelType, fmt.Sprintf("unknown channel type: %v", ch.ChannelType()))
+		}
+	}
+
+	c.mu.Lock()
+	for _, ch := range c.channelHandlers {
+		close(ch)
+	}
+	c.channelHandlers = nil
+	c.mu.Unlock()
+}
+
+// Dial starts a client connection to the given SSH server. It is a
+// convenience function that connects to the given network address,
+// initiates the SSH handshake, and then sets up a Client.  For access
+// to incoming channels and requests, use net.Dial with NewClientConn
+// instead.
+func Dial(network, addr string, config *ClientConfig) (*Client, error) {
+	conn, err := net.DialTimeout(network, addr, config.Timeout)
+	if err != nil {
+		return nil, err
+	}
+	c, chans, reqs, err := NewClientConn(conn, addr, config)
+	if err != nil {
+		return nil, err
+	}
+	return NewClient(c, chans, reqs), nil
+}
+
+// HostKeyCallback is the function type used for verifying server
+// keys.  A HostKeyCallback must return nil if the host key is OK, or
+// an error to reject it. It receives the hostname as passed to Dial
+// or NewClientConn. The remote address is the RemoteAddr of the
+// net.Conn underlying the the SSH connection.
+type HostKeyCallback func(hostname string, remote net.Addr, key PublicKey) error
+
+// BannerCallback is the function type used for treat the banner sent by
+// the server. A BannerCallback receives the message sent by the remote server.
+type BannerCallback func(message string) error
+
+// A ClientConfig structure is used to configure a Client. It must not be
+// modified after having been passed to an SSH function.
+type ClientConfig struct {
+	// Config contains configuration that is shared between clients and
+	// servers.
+	Config
+
+	// User contains the username to authenticate as.
+	User string
+
+	// Auth contains possible authentication methods to use with the
+	// server. Only the first instance of a particular RFC 4252 method will
+	// be used during authentication.
+	Auth []AuthMethod
+
+	// HostKeyCallback is called during the cryptographic
+	// handshake to validate the server's host key. The client
+	// configuration must supply this callback for the connection
+	// to succeed. The functions InsecureIgnoreHostKey or
+	// FixedHostKey can be used for simplistic host key checks.
+	HostKeyCallback HostKeyCallback
+
+	// BannerCallback is called during the SSH dance to display a custom
+	// server's message. The client configuration can supply this callback to
+	// handle it as wished. The function BannerDisplayStderr can be used for
+	// simplistic display on Stderr.
+	BannerCallback BannerCallback
+
+	// ClientVersion contains the version identification string that will
+	// be used for the connection. If empty, a reasonable default is used.
+	ClientVersion string
+
+	// HostKeyAlgorithms lists the key types that the client will
+	// accept from the server as host key, in order of
+	// preference. If empty, a reasonable default is used. Any
+	// string returned from PublicKey.Type method may be used, or
+	// any of the CertAlgoXxxx and KeyAlgoXxxx constants.
+	HostKeyAlgorithms []string
+
+	// Timeout is the maximum amount of time for the TCP connection to establish.
+	//
+	// A Timeout of zero means no timeout.
+	Timeout time.Duration
+}
+
+// InsecureIgnoreHostKey returns a function that can be used for
+// ClientConfig.HostKeyCallback to accept any host key. It should
+// not be used for production code.
+func InsecureIgnoreHostKey() HostKeyCallback {
+	return func(hostname string, remote net.Addr, key PublicKey) error {
+		return nil
+	}
+}
+
+type fixedHostKey struct {
+	key PublicKey
+}
+
+func (f *fixedHostKey) check(hostname string, remote net.Addr, key PublicKey) error {
+	if f.key == nil {
+		return fmt.Errorf("ssh: required host key was nil")
+	}
+	if !bytes.Equal(key.Marshal(), f.key.Marshal()) {
+		return fmt.Errorf("ssh: host key mismatch")
+	}
+	return nil
+}
+
+// FixedHostKey returns a function for use in
+// ClientConfig.HostKeyCallback to accept only a specific host key.
+func FixedHostKey(key PublicKey) HostKeyCallback {
+	hk := &fixedHostKey{key}
+	return hk.check
+}
+
+// BannerDisplayStderr returns a function that can be used for
+// ClientConfig.BannerCallback to display banners on os.Stderr.
+func BannerDisplayStderr() BannerCallback {
+	return func(banner string) error {
+		_, err := os.Stderr.WriteString(banner)
+
+		return err
+	}
+}

vendor/golang.org/x/crypto/ssh/client_auth.go

@@ -0,0 +1,510 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+)
+
+// clientAuthenticate authenticates with the remote server. See RFC 4252.
+func (c *connection) clientAuthenticate(config *ClientConfig) error {
+	// initiate user auth session
+	if err := c.transport.writePacket(Marshal(&serviceRequestMsg{serviceUserAuth})); err != nil {
+		return err
+	}
+	packet, err := c.transport.readPacket()
+	if err != nil {
+		return err
+	}
+	var serviceAccept serviceAcceptMsg
+	if err := Unmarshal(packet, &serviceAccept); err != nil {
+		return err
+	}
+
+	// during the authentication phase the client first attempts the "none" method
+	// then any untried methods suggested by the server.
+	tried := make(map[string]bool)
+	var lastMethods []string
+
+	sessionID := c.transport.getSessionID()
+	for auth := AuthMethod(new(noneAuth)); auth != nil; {
+		ok, methods, err := auth.auth(sessionID, config.User, c.transport, config.Rand)
+		if err != nil {
+			return err
+		}
+		if ok {
+			// success
+			return nil
+		}
+		tried[auth.method()] = true
+		if methods == nil {
+			methods = lastMethods
+		}
+		lastMethods = methods
+
+		auth = nil
+
+	findNext:
+		for _, a := range config.Auth {
+			candidateMethod := a.method()
+			if tried[candidateMethod] {
+				continue
+			}
+			for _, meth := range methods {
+				if meth == candidateMethod {
+					auth = a
+					break findNext
+				}
+			}
+		}
+	}
+	return fmt.Errorf("ssh: unable to authenticate, attempted methods %v, no supported methods remain", keys(tried))
+}
+
+func keys(m map[string]bool) []string {
+	s := make([]string, 0, len(m))
+
+	for key := range m {
+		s = append(s, key)
+	}
+	return s
+}
+
+// An AuthMethod represents an instance of an RFC 4252 authentication method.
+type AuthMethod interface {
+	// auth authenticates user over transport t.
+	// Returns true if authentication is successful.
+	// If authentication is not successful, a []string of alternative
+	// method names is returned. If the slice is nil, it will be ignored
+	// and the previous set of possible methods will be reused.
+	auth(session []byte, user string, p packetConn, rand io.Reader) (bool, []string, error)
+
+	// method returns the RFC 4252 method name.
+	method() string
+}
+
+// "none" authentication, RFC 4252 section 5.2.
+type noneAuth int
+
+func (n *noneAuth) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
+	if err := c.writePacket(Marshal(&userAuthRequestMsg{
+		User:    user,
+		Service: serviceSSH,
+		Method:  "none",
+	})); err != nil {
+		return false, nil, err
+	}
+
+	return handleAuthResponse(c)
+}
+
+func (n *noneAuth) method() string {
+	return "none"
+}
+
+// passwordCallback is an AuthMethod that fetches the password through
+// a function call, e.g. by prompting the user.
+type passwordCallback func() (password string, err error)
+
+func (cb passwordCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
+	type passwordAuthMsg struct {
+		User     string `sshtype:"50"`
+		Service  string
+		Method   string
+		Reply    bool
+		Password string
+	}
+
+	pw, err := cb()
+	// REVIEW NOTE: is there a need to support skipping a password attempt?
+	// The program may only find out that the user doesn't have a password
+	// when prompting.
+	if err != nil {
+		return false, nil, err
+	}
+
+	if err := c.writePacket(Marshal(&passwordAuthMsg{
+		User:     user,
+		Service:  serviceSSH,
+		Method:   cb.method(),
+		Reply:    false,
+		Password: pw,
+	})); err != nil {
+		return false, nil, err
+	}
+
+	return handleAuthResponse(c)
+}
+
+func (cb passwordCallback) method() string {
+	return "password"
+}
+
+// Password returns an AuthMethod using the given password.
+func Password(secret string) AuthMethod {
+	return passwordCallback(func() (string, error) { return secret, nil })
+}
+
+// PasswordCallback returns an AuthMethod that uses a callback for
+// fetching a password.
+func PasswordCallback(prompt func() (secret string, err error)) AuthMethod {
+	return passwordCallback(prompt)
+}
+
+type publickeyAuthMsg struct {
+	User    string `sshtype:"50"`
+	Service string
+	Method  string
+	// HasSig indicates to the receiver packet that the auth request is signed and
+	// should be used for authentication of the request.
+	HasSig   bool
+	Algoname string
+	PubKey   []byte
+	// Sig is tagged with "rest" so Marshal will exclude it during
+	// validateKey
+	Sig []byte `ssh:"rest"`
+}
+
+// publicKeyCallback is an AuthMethod that uses a set of key
+// pairs for authentication.
+type publicKeyCallback func() ([]Signer, error)
+
+func (cb publicKeyCallback) method() string {
+	return "publickey"
+}
+
+func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
+	// Authentication is performed by sending an enquiry to test if a key is
+	// acceptable to the remote. If the key is acceptable, the client will
+	// attempt to authenticate with the valid key.  If not the client will repeat
+	// the process with the remaining keys.
+
+	signers, err := cb()
+	if err != nil {
+		return false, nil, err
+	}
+	var methods []string
+	for _, signer := range signers {
+		ok, err := validateKey(signer.PublicKey(), user, c)
+		if err != nil {
+			return false, nil, err
+		}
+		if !ok {
+			continue
+		}
+
+		pub := signer.PublicKey()
+		pubKey := pub.Marshal()
+		sign, err := signer.Sign(rand, buildDataSignedForAuth(session, userAuthRequestMsg{
+			User:    user,
+			Service: serviceSSH,
+			Method:  cb.method(),
+		}, []byte(pub.Type()), pubKey))
+		if err != nil {
+			return false, nil, err
+		}
+
+		// manually wrap the serialized signature in a string
+		s := Marshal(sign)
+		sig := make([]byte, stringLength(len(s)))
+		marshalString(sig, s)
+		msg := publickeyAuthMsg{
+			User:     user,
+			Service:  serviceSSH,
+			Method:   cb.method(),
+			HasSig:   true,
+			Algoname: pub.Type(),
+			PubKey:   pubKey,
+			Sig:      sig,
+		}
+		p := Marshal(&msg)
+		if err := c.writePacket(p); err != nil {
+			return false, nil, err
+		}
+		var success bool
+		success, methods, err = handleAuthResponse(c)
+		if err != nil {
+			return false, nil, err
+		}
+
+		// If authentication succeeds or the list of available methods does not
+		// contain the "publickey" method, do not attempt to authenticate with any
+		// other keys.  According to RFC 4252 Section 7, the latter can occur when
+		// additional authentication methods are required.
+		if success || !containsMethod(methods, cb.method()) {
+			return success, methods, err
+		}
+	}
+
+	return false, methods, nil
+}
+
+func containsMethod(methods []string, method string) bool {
+	for _, m := range methods {
+		if m == method {
+			return true
+		}
+	}
+
+	return false
+}
+
+// validateKey validates the key provided is acceptable to the server.
+func validateKey(key PublicKey, user string, c packetConn) (bool, error) {
+	pubKey := key.Marshal()
+	msg := publickeyAuthMsg{
+		User:     user,
+		Service:  serviceSSH,
+		Method:   "publickey",
+		HasSig:   false,
+		Algoname: key.Type(),
+		PubKey:   pubKey,
+	}
+	if err := c.writePacket(Marshal(&msg)); err != nil {
+		return false, err
+	}
+
+	return confirmKeyAck(key, c)
+}
+
+func confirmKeyAck(key PublicKey, c packetConn) (bool, error) {
+	pubKey := key.Marshal()
+	algoname := key.Type()
+
+	for {
+		packet, err := c.readPacket()
+		if err != nil {
+			return false, err
+		}
+		switch packet[0] {
+		case msgUserAuthBanner:
+			if err := handleBannerResponse(c, packet); err != nil {
+				return false, err
+			}
+		case msgUserAuthPubKeyOk:
+			var msg userAuthPubKeyOkMsg
+			if err := Unmarshal(packet, &msg); err != nil {
+				return false, err
+			}
+			if msg.Algo != algoname || !bytes.Equal(msg.PubKey, pubKey) {
+				return false, nil
+			}
+			return true, nil
+		case msgUserAuthFailure:
+			return false, nil
+		default:
+			return false, unexpectedMessageError(msgUserAuthSuccess, packet[0])
+		}
+	}
+}
+
+// PublicKeys returns an AuthMethod that uses the given key
+// pairs.
+func PublicKeys(signers ...Signer) AuthMethod {
+	return publicKeyCallback(func() ([]Signer, error) { return signers, nil })
+}
+
+// PublicKeysCallback returns an AuthMethod that runs the given
+// function to obtain a list of key pairs.
+func PublicKeysCallback(getSigners func() (signers []Signer, err error)) AuthMethod {
+	return publicKeyCallback(getSigners)
+}
+
+// handleAuthResponse returns whether the preceding authentication request succeeded
+// along with a list of remaining authentication methods to try next and
+// an error if an unexpected response was received.
+func handleAuthResponse(c packetConn) (bool, []string, error) {
+	for {
+		packet, err := c.readPacket()
+		if err != nil {
+			return false, nil, err
+		}
+
+		switch packet[0] {
+		case msgUserAuthBanner:
+			if err := handleBannerResponse(c, packet); err != nil {
+				return false, nil, err
+			}
+		case msgUserAuthFailure:
+			var msg userAuthFailureMsg
+			if err := Unmarshal(packet, &msg); err != nil {
+				return false, nil, err
+			}
+			return false, msg.Methods, nil
+		case msgUserAuthSuccess:
+			return true, nil, nil
+		default:
+			return false, nil, unexpectedMessageError(msgUserAuthSuccess, packet[0])
+		}
+	}
+}
+
+func handleBannerResponse(c packetConn, packet []byte) error {
+	var msg userAuthBannerMsg
+	if err := Unmarshal(packet, &msg); err != nil {
+		return err
+	}
+
+	transport, ok := c.(*handshakeTransport)
+	if !ok {
+		return nil
+	}
+
+	if transport.bannerCallback != nil {
+		return transport.bannerCallback(msg.Message)
+	}
+
+	return nil
+}
+
+// KeyboardInteractiveChallenge should print questions, optionally
+// disabling echoing (e.g. for passwords), and return all the answers.
+// Challenge may be called multiple times in a single session. After
+// successful authentication, the server may send a challenge with no
+// questions, for which the user and instruction messages should be
+// printed.  RFC 4256 section 3.3 details how the UI should behave for
+// both CLI and GUI environments.
+type KeyboardInteractiveChallenge func(user, instruction string, questions []string, echos []bool) (answers []string, err error)
+
+// KeyboardInteractive returns an AuthMethod using a prompt/response
+// sequence controlled by the server.
+func KeyboardInteractive(challenge KeyboardInteractiveChallenge) AuthMethod {
+	return challenge
+}
+
+func (cb KeyboardInteractiveChallenge) method() string {
+	return "keyboard-interactive"
+}
+
+func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
+	type initiateMsg struct {
+		User       string `sshtype:"50"`
+		Service    string
+		Method     string
+		Language   string
+		Submethods string
+	}
+
+	if err := c.writePacket(Marshal(&initiateMsg{
+		User:    user,
+		Service: serviceSSH,
+		Method:  "keyboard-interactive",
+	})); err != nil {
+		return false, nil, err
+	}
+
+	for {
+		packet, err := c.readPacket()
+		if err != nil {
+			return false, nil, err
+		}
+
+		// like handleAuthResponse, but with less options.
+		switch packet[0] {
+		case msgUserAuthBanner:
+			if err := handleBannerResponse(c, packet); err != nil {
+				return false, nil, err
+			}
+			continue
+		case msgUserAuthInfoRequest:
+			// OK
+		case msgUserAuthFailure:
+			var msg userAuthFailureMsg
+			if err := Unmarshal(packet, &msg); err != nil {
+				return false, nil, err
+			}
+			return false, msg.Methods, nil
+		case msgUserAuthSuccess:
+			return true, nil, nil
+		default:
+			return false, nil, unexpectedMessageError(msgUserAuthInfoRequest, packet[0])
+		}
+
+		var msg userAuthInfoRequestMsg
+		if err := Unmarshal(packet, &msg); err != nil {
+			return false, nil, err
+		}
+
+		// Manually unpack the prompt/echo pairs.
+		rest := msg.Prompts
+		var prompts []string
+		var echos []bool
+		for i := 0; i < int(msg.NumPrompts); i++ {
+			prompt, r, ok := parseString(rest)
+			if !ok || len(r) == 0 {
+				return false, nil, errors.New("ssh: prompt format error")
+			}
+			prompts = append(prompts, string(prompt))
+			echos = append(echos, r[0] != 0)
+			rest = r[1:]
+		}
+
+		if len(rest) != 0 {
+			return false, nil, errors.New("ssh: extra data following keyboard-interactive pairs")
+		}
+
+		answers, err := cb(msg.User, msg.Instruction, prompts, echos)
+		if err != nil {
+			return false, nil, err
+		}
+
+		if len(answers) != len(prompts) {
+			return false, nil, errors.New("ssh: not enough answers from keyboard-interactive callback")
+		}
+		responseLength := 1 + 4
+		for _, a := range answers {
+			responseLength += stringLength(len(a))
+		}
+		serialized := make([]byte, responseLength)
+		p := serialized
+		p[0] = msgUserAuthInfoResponse
+		p = p[1:]
+		p = marshalUint32(p, uint32(len(answers)))
+		for _, a := range answers {
+			p = marshalString(p, []byte(a))
+		}
+
+		if err := c.writePacket(serialized); err != nil {
+			return false, nil, err
+		}
+	}
+}
+
+type retryableAuthMethod struct {
+	authMethod AuthMethod
+	maxTries   int
+}
+
+func (r *retryableAuthMethod) auth(session []byte, user string, c packetConn, rand io.Reader) (ok bool, methods []string, err error) {
+	for i := 0; r.maxTries <= 0 || i < r.maxTries; i++ {
+		ok, methods, err = r.authMethod.auth(session, user, c, rand)
+		if ok || err != nil { // either success or error terminate
+			return ok, methods, err
+		}
+	}
+	return ok, methods, err
+}
+
+func (r *retryableAuthMethod) method() string {
+	return r.authMethod.method()
+}
+
+// RetryableAuthMethod is a decorator for other auth methods enabling them to
+// be retried up to maxTries before considering that AuthMethod itself failed.
+// If maxTries is <= 0, will retry indefinitely
+//
+// This is useful for interactive clients using challenge/response type
+// authentication (e.g. Keyboard-Interactive, Password, etc) where the user
+// could mistype their response resulting in the server issuing a
+// SSH_MSG_USERAUTH_FAILURE (rfc4252 #8 [password] and rfc4256 #3.4
+// [keyboard-interactive]); Without this decorator, the non-retryable
+// AuthMethod would be removed from future consideration, and never tried again
+// (and so the user would never be able to retry their entry).
+func RetryableAuthMethod(auth AuthMethod, maxTries int) AuthMethod {
+	return &retryableAuthMethod{authMethod: auth, maxTries: maxTries}
+}

vendor/golang.org/x/crypto/ssh/common.go

@@ -0,0 +1,373 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"crypto"
+	"crypto/rand"
+	"fmt"
+	"io"
+	"math"
+	"sync"
+
+	_ "crypto/sha1"
+	_ "crypto/sha256"
+	_ "crypto/sha512"
+)
+
+// These are string constants in the SSH protocol.
+const (
+	compressionNone = "none"
+	serviceUserAuth = "ssh-userauth"
+	serviceSSH      = "ssh-connection"
+)
+
+// supportedCiphers specifies the supported ciphers in preference order.
+var supportedCiphers = []string{
+	"aes128-ctr", "aes192-ctr", "aes256-ctr",
+	"aes128-gcm@openssh.com",
+	"arcfour256", "arcfour128",
+}
+
+// supportedKexAlgos specifies the supported key-exchange algorithms in
+// preference order.
+var supportedKexAlgos = []string{
+	kexAlgoCurve25519SHA256,
+	// P384 and P521 are not constant-time yet, but since we don't
+	// reuse ephemeral keys, using them for ECDH should be OK.
+	kexAlgoECDH256, kexAlgoECDH384, kexAlgoECDH521,
+	kexAlgoDH14SHA1, kexAlgoDH1SHA1,
+}
+
+// supportedHostKeyAlgos specifies the supported host-key algorithms (i.e. methods
+// of authenticating servers) in preference order.
+var supportedHostKeyAlgos = []string{
+	CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01,
+	CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01,
+
+	KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521,
+	KeyAlgoRSA, KeyAlgoDSA,
+
+	KeyAlgoED25519,
+}
+
+// supportedMACs specifies a default set of MAC algorithms in preference order.
+// This is based on RFC 4253, section 6.4, but with hmac-md5 variants removed
+// because they have reached the end of their useful life.
+var supportedMACs = []string{
+	"hmac-sha2-256-etm@openssh.com", "hmac-sha2-256", "hmac-sha1", "hmac-sha1-96",
+}
+
+var supportedCompressions = []string{compressionNone}
+
+// hashFuncs keeps the mapping of supported algorithms to their respective
+// hashes needed for signature verification.
+var hashFuncs = map[string]crypto.Hash{
+	KeyAlgoRSA:          crypto.SHA1,
+	KeyAlgoDSA:          crypto.SHA1,
+	KeyAlgoECDSA256:     crypto.SHA256,
+	KeyAlgoECDSA384:     crypto.SHA384,
+	KeyAlgoECDSA521:     crypto.SHA512,
+	CertAlgoRSAv01:      crypto.SHA1,
+	CertAlgoDSAv01:      crypto.SHA1,
+	CertAlgoECDSA256v01: crypto.SHA256,
+	CertAlgoECDSA384v01: crypto.SHA384,
+	CertAlgoECDSA521v01: crypto.SHA512,
+}
+
+// unexpectedMessageError results when the SSH message that we received didn't
+// match what we wanted.
+func unexpectedMessageError(expected, got uint8) error {
+	return fmt.Errorf("ssh: unexpected message type %d (expected %d)", got, expected)
+}
+
+// parseError results from a malformed SSH message.
+func parseError(tag uint8) error {
+	return fmt.Errorf("ssh: parse error in message type %d", tag)
+}
+
+func findCommon(what string, client []string, server []string) (common string, err error) {
+	for _, c := range client {
+		for _, s := range server {
+			if c == s {
+				return c, nil
+			}
+		}
+	}
+	return "", fmt.Errorf("ssh: no common algorithm for %s; client offered: %v, server offered: %v", what, client, server)
+}
+
+type directionAlgorithms struct {
+	Cipher      string
+	MAC         string
+	Compression string
+}
+
+// rekeyBytes returns a rekeying intervals in bytes.
+func (a *directionAlgorithms) rekeyBytes() int64 {
+	// According to RFC4344 block ciphers should rekey after
+	// 2^(BLOCKSIZE/4) blocks. For all AES flavors BLOCKSIZE is
+	// 128.
+	switch a.Cipher {
+	case "aes128-ctr", "aes192-ctr", "aes256-ctr", gcmCipherID, aes128cbcID:
+		return 16 * (1 << 32)
+
+	}
+
+	// For others, stick with RFC4253 recommendation to rekey after 1 Gb of data.
+	return 1 << 30
+}
+
+type algorithms struct {
+	kex     string
+	hostKey string
+	w       directionAlgorithms
+	r       directionAlgorithms
+}
+
+func findAgreedAlgorithms(clientKexInit, serverKexInit *kexInitMsg) (algs *algorithms, err error) {
+	result := &algorithms{}
+
+	result.kex, err = findCommon("key exchange", clientKexInit.KexAlgos, serverKexInit.KexAlgos)
+	if err != nil {
+		return
+	}
+
+	result.hostKey, err = findCommon("host key", clientKexInit.ServerHostKeyAlgos, serverKexInit.ServerHostKeyAlgos)
+	if err != nil {
+		return
+	}
+
+	result.w.Cipher, err = findCommon("client to server cipher", clientKexInit.CiphersClientServer, serverKexInit.CiphersClientServer)
+	if err != nil {
+		return
+	}
+
+	result.r.Cipher, err = findCommon("server to client cipher", clientKexInit.CiphersServerClient, serverKexInit.CiphersServerClient)
+	if err != nil {
+		return
+	}
+
+	result.w.MAC, err = findCommon("client to server MAC", clientKexInit.MACsClientServer, serverKexInit.MACsClientServer)
+	if err != nil {
+		return
+	}
+
+	result.r.MAC, err = findCommon("server to client MAC", clientKexInit.MACsServerClient, serverKexInit.MACsServerClient)
+	if err != nil {
+		return
+	}
+
+	result.w.Compression, err = findCommon("client to server compression", clientKexInit.CompressionClientServer, serverKexInit.CompressionClientServer)
+	if err != nil {
+		return
+	}
+
+	result.r.Compression, err = findCommon("server to client compression", clientKexInit.CompressionServerClient, serverKexInit.CompressionServerClient)
+	if err != nil {
+		return
+	}
+
+	return result, nil
+}
+
+// If rekeythreshold is too small, we can't make any progress sending
+// stuff.
+const minRekeyThreshold uint64 = 256
+
+// Config contains configuration data common to both ServerConfig and
+// ClientConfig.
+type Config struct {
+	// Rand provides the source of entropy for cryptographic
+	// primitives. If Rand is nil, the cryptographic random reader
+	// in package crypto/rand will be used.
+	Rand io.Reader
+
+	// The maximum number of bytes sent or received after which a
+	// new key is negotiated. It must be at least 256. If
+	// unspecified, a size suitable for the chosen cipher is used.
+	RekeyThreshold uint64
+
+	// The allowed key exchanges algorithms. If unspecified then a
+	// default set of algorithms is used.
+	KeyExchanges []string
+
+	// The allowed cipher algorithms. If unspecified then a sensible
+	// default is used.
+	Ciphers []string
+
+	// The allowed MAC algorithms. If unspecified then a sensible default
+	// is used.
+	MACs []string
+}
+
+// SetDefaults sets sensible values for unset fields in config. This is
+// exported for testing: Configs passed to SSH functions are copied and have
+// default values set automatically.
+func (c *Config) SetDefaults() {
+	if c.Rand == nil {
+		c.Rand = rand.Reader
+	}
+	if c.Ciphers == nil {
+		c.Ciphers = supportedCiphers
+	}
+	var ciphers []string
+	for _, c := range c.Ciphers {
+		if cipherModes[c] != nil {
+			// reject the cipher if we have no cipherModes definition
+			ciphers = append(ciphers, c)
+		}
+	}
+	c.Ciphers = ciphers
+
+	if c.KeyExchanges == nil {
+		c.KeyExchanges = supportedKexAlgos
+	}
+
+	if c.MACs == nil {
+		c.MACs = supportedMACs
+	}
+
+	if c.RekeyThreshold == 0 {
+		// cipher specific default
+	} else if c.RekeyThreshold < minRekeyThreshold {
+		c.RekeyThreshold = minRekeyThreshold
+	} else if c.RekeyThreshold >= math.MaxInt64 {
+		// Avoid weirdness if somebody uses -1 as a threshold.
+		c.RekeyThreshold = math.MaxInt64
+	}
+}
+
+// buildDataSignedForAuth returns the data that is signed in order to prove
+// possession of a private key. See RFC 4252, section 7.
+func buildDataSignedForAuth(sessionId []byte, req userAuthRequestMsg, algo, pubKey []byte) []byte {
+	data := struct {
+		Session []byte
+		Type    byte
+		User    string
+		Service string
+		Method  string
+		Sign    bool
+		Algo    []byte
+		PubKey  []byte
+	}{
+		sessionId,
+		msgUserAuthRequest,
+		req.User,
+		req.Service,
+		req.Method,
+		true,
+		algo,
+		pubKey,
+	}
+	return Marshal(data)
+}
+
+func appendU16(buf []byte, n uint16) []byte {
+	return append(buf, byte(n>>8), byte(n))
+}
+
+func appendU32(buf []byte, n uint32) []byte {
+	return append(buf, byte(n>>24), byte(n>>16), byte(n>>8), byte(n))
+}
+
+func appendU64(buf []byte, n uint64) []byte {
+	return append(buf,
+		byte(n>>56), byte(n>>48), byte(n>>40), byte(n>>32),
+		byte(n>>24), byte(n>>16), byte(n>>8), byte(n))
+}
+
+func appendInt(buf []byte, n int) []byte {
+	return appendU32(buf, uint32(n))
+}
+
+func appendString(buf []byte, s string) []byte {
+	buf = appendU32(buf, uint32(len(s)))
+	buf = append(buf, s...)
+	return buf
+}
+
+func appendBool(buf []byte, b bool) []byte {
+	if b {
+		return append(buf, 1)
+	}
+	return append(buf, 0)
+}
+
+// newCond is a helper to hide the fact that there is no usable zero
+// value for sync.Cond.
+func newCond() *sync.Cond { return sync.NewCond(new(sync.Mutex)) }
+
+// window represents the buffer available to clients
+// wishing to write to a channel.
+type window struct {
+	*sync.Cond
+	win          uint32 // RFC 4254 5.2 says the window size can grow to 2^32-1
+	writeWaiters int
+	closed       bool
+}
+
+// add adds win to the amount of window available
+// for consumers.
+func (w *window) add(win uint32) bool {
+	// a zero sized window adjust is a noop.
+	if win == 0 {
+		return true
+	}
+	w.L.Lock()
+	if w.win+win < win {
+		w.L.Unlock()
+		return false
+	}
+	w.win += win
+	// It is unusual that multiple goroutines would be attempting to reserve
+	// window space, but not guaranteed. Use broadcast to notify all waiters
+	// that additional window is available.
+	w.Broadcast()
+	w.L.Unlock()
+	return true
+}
+
+// close sets the window to closed, so all reservations fail
+// immediately.
+func (w *window) close() {
+	w.L.Lock()
+	w.closed = true
+	w.Broadcast()
+	w.L.Unlock()
+}
+
+// reserve reserves win from the available window capacity.
+// If no capacity remains, reserve will block. reserve may
+// return less than requested.
+func (w *window) reserve(win uint32) (uint32, error) {
+	var err error
+	w.L.Lock()
+	w.writeWaiters++
+	w.Broadcast()
+	for w.win == 0 && !w.closed {
+		w.Wait()
+	}
+	w.writeWaiters--
+	if w.win < win {
+		win = w.win
+	}
+	w.win -= win
+	if w.closed {
+		err = io.EOF
+	}
+	w.L.Unlock()
+	return win, err
+}
+
+// waitWriterBlocked waits until some goroutine is blocked for further
+// writes. It is used in tests only.
+func (w *window) waitWriterBlocked() {
+	w.Cond.L.Lock()
+	for w.writeWaiters == 0 {
+		w.Cond.Wait()
+	}
+	w.Cond.L.Unlock()
+}

vendor/golang.org/x/crypto/ssh/connection.go

@@ -0,0 +1,143 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"fmt"
+	"net"
+)
+
+// OpenChannelError is returned if the other side rejects an
+// OpenChannel request.
+type OpenChannelError struct {
+	Reason  RejectionReason
+	Message string
+}
+
+func (e *OpenChannelError) Error() string {
+	return fmt.Sprintf("ssh: rejected: %s (%s)", e.Reason, e.Message)
+}
+
+// ConnMetadata holds metadata for the connection.
+type ConnMetadata interface {
+	// User returns the user ID for this connection.
+	User() string
+
+	// SessionID returns the session hash, also denoted by H.
+	SessionID() []byte
+
+	// ClientVersion returns the client's version string as hashed
+	// into the session ID.
+	ClientVersion() []byte
+
+	// ServerVersion returns the server's version string as hashed
+	// into the session ID.
+	ServerVersion() []byte
+
+	// RemoteAddr returns the remote address for this connection.
+	RemoteAddr() net.Addr
+
+	// LocalAddr returns the local address for this connection.
+	LocalAddr() net.Addr
+}
+
+// Conn represents an SSH connection for both server and client roles.
+// Conn is the basis for implementing an application layer, such
+// as ClientConn, which implements the traditional shell access for
+// clients.
+type Conn interface {
+	ConnMetadata
+
+	// SendRequest sends a global request, and returns the
+	// reply. If wantReply is true, it returns the response status
+	// and payload. See also RFC4254, section 4.
+	SendRequest(name string, wantReply bool, payload []byte) (bool, []byte, error)
+
+	// OpenChannel tries to open an channel. If the request is
+	// rejected, it returns *OpenChannelError. On success it returns
+	// the SSH Channel and a Go channel for incoming, out-of-band
+	// requests. The Go channel must be serviced, or the
+	// connection will hang.
+	OpenChannel(name string, data []byte) (Channel, <-chan *Request, error)
+
+	// Close closes the underlying network connection
+	Close() error
+
+	// Wait blocks until the connection has shut down, and returns the
+	// error causing the shutdown.
+	Wait() error
+
+	// TODO(hanwen): consider exposing:
+	//   RequestKeyChange
+	//   Disconnect
+}
+
+// DiscardRequests consumes and rejects all requests from the
+// passed-in channel.
+func DiscardRequests(in <-chan *Request) {
+	for req := range in {
+		if req.WantReply {
+			req.Reply(false, nil)
+		}
+	}
+}
+
+// A connection represents an incoming connection.
+type connection struct {
+	transport *handshakeTransport
+	sshConn
+
+	// The connection protocol.
+	*mux
+}
+
+func (c *connection) Close() error {
+	return c.sshConn.conn.Close()
+}
+
+// sshconn provides net.Conn metadata, but disallows direct reads and
+// writes.
+type sshConn struct {
+	conn net.Conn
+
+	user          string
+	sessionID     []byte
+	clientVersion []byte
+	serverVersion []byte
+}
+
+func dup(src []byte) []byte {
+	dst := make([]byte, len(src))
+	copy(dst, src)
+	return dst
+}
+
+func (c *sshConn) User() string {
+	return c.user
+}
+
+func (c *sshConn) RemoteAddr() net.Addr {
+	return c.conn.RemoteAddr()
+}
+
+func (c *sshConn) Close() error {
+	return c.conn.Close()
+}
+
+func (c *sshConn) LocalAddr() net.Addr {
+	return c.conn.LocalAddr()
+}
+
+func (c *sshConn) SessionID() []byte {
+	return dup(c.sessionID)
+}
+
+func (c *sshConn) ClientVersion() []byte {
+	return dup(c.clientVersion)
+}
+
+func (c *sshConn) ServerVersion() []byte {
+	return dup(c.serverVersion)
+}

vendor/golang.org/x/crypto/ssh/doc.go

@@ -0,0 +1,21 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package ssh implements an SSH client and server.
+
+SSH is a transport security protocol, an authentication protocol and a
+family of application protocols. The most typical application level
+protocol is a remote shell and this is specifically implemented.  However,
+the multiplexed nature of SSH is exposed to users that wish to support
+others.
+
+References:
+  [PROTOCOL.certkeys]: http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.certkeys?rev=HEAD
+  [SSH-PARAMETERS]:    http://www.iana.org/assignments/ssh-parameters/ssh-parameters.xml#ssh-parameters-1
+
+This package does not fall under the stability promise of the Go language itself,
+so its API may be changed when pressing needs arise.
+*/
+package ssh // import "golang.org/x/crypto/ssh"

vendor/golang.org/x/crypto/ssh/handshake.go

@@ -0,0 +1,646 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"crypto/rand"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"sync"
+)
+
+// debugHandshake, if set, prints messages sent and received.  Key
+// exchange messages are printed as if DH were used, so the debug
+// messages are wrong when using ECDH.
+const debugHandshake = false
+
+// chanSize sets the amount of buffering SSH connections. This is
+// primarily for testing: setting chanSize=0 uncovers deadlocks more
+// quickly.
+const chanSize = 16
+
+// keyingTransport is a packet based transport that supports key
+// changes. It need not be thread-safe. It should pass through
+// msgNewKeys in both directions.
+type keyingTransport interface {
+	packetConn
+
+	// prepareKeyChange sets up a key change. The key change for a
+	// direction will be effected if a msgNewKeys message is sent
+	// or received.
+	prepareKeyChange(*algorithms, *kexResult) error
+}
+
+// handshakeTransport implements rekeying on top of a keyingTransport
+// and offers a thread-safe writePacket() interface.
+type handshakeTransport struct {
+	conn   keyingTransport
+	config *Config
+
+	serverVersion []byte
+	clientVersion []byte
+
+	// hostKeys is non-empty if we are the server. In that case,
+	// it contains all host keys that can be used to sign the
+	// connection.
+	hostKeys []Signer
+
+	// hostKeyAlgorithms is non-empty if we are the client. In that case,
+	// we accept these key types from the server as host key.
+	hostKeyAlgorithms []string
+
+	// On read error, incoming is closed, and readError is set.
+	incoming  chan []byte
+	readError error
+
+	mu             sync.Mutex
+	writeError     error
+	sentInitPacket []byte
+	sentInitMsg    *kexInitMsg
+	pendingPackets [][]byte // Used when a key exchange is in progress.
+
+	// If the read loop wants to schedule a kex, it pings this
+	// channel, and the write loop will send out a kex
+	// message.
+	requestKex chan struct{}
+
+	// If the other side requests or confirms a kex, its kexInit
+	// packet is sent here for the write loop to find it.
+	startKex chan *pendingKex
+
+	// data for host key checking
+	hostKeyCallback HostKeyCallback
+	dialAddress     string
+	remoteAddr      net.Addr
+
+	// bannerCallback is non-empty if we are the client and it has been set in
+	// ClientConfig. In that case it is called during the user authentication
+	// dance to handle a custom server's message.
+	bannerCallback BannerCallback
+
+	// Algorithms agreed in the last key exchange.
+	algorithms *algorithms
+
+	readPacketsLeft uint32
+	readBytesLeft   int64
+
+	writePacketsLeft uint32
+	writeBytesLeft   int64
+
+	// The session ID or nil if first kex did not complete yet.
+	sessionID []byte
+}
+
+type pendingKex struct {
+	otherInit []byte
+	done      chan error
+}
+
+func newHandshakeTransport(conn keyingTransport, config *Config, clientVersion, serverVersion []byte) *handshakeTransport {
+	t := &handshakeTransport{
+		conn:          conn,
+		serverVersion: serverVersion,
+		clientVersion: clientVersion,
+		incoming:      make(chan []byte, chanSize),
+		requestKex:    make(chan struct{}, 1),
+		startKex:      make(chan *pendingKex, 1),
+
+		config: config,
+	}
+	t.resetReadThresholds()
+	t.resetWriteThresholds()
+
+	// We always start with a mandatory key exchange.
+	t.requestKex <- struct{}{}
+	return t
+}
+
+func newClientTransport(conn keyingTransport, clientVersion, serverVersion []byte, config *ClientConfig, dialAddr string, addr net.Addr) *handshakeTransport {
+	t := newHandshakeTransport(conn, &config.Config, clientVersion, serverVersion)
+	t.dialAddress = dialAddr
+	t.remoteAddr = addr
+	t.hostKeyCallback = config.HostKeyCallback
+	t.bannerCallback = config.BannerCallback
+	if config.HostKeyAlgorithms != nil {
+		t.hostKeyAlgorithms = config.HostKeyAlgorithms
+	} else {
+		t.hostKeyAlgorithms = supportedHostKeyAlgos
+	}
+	go t.readLoop()
+	go t.kexLoop()
+	return t
+}
+
+func newServerTransport(conn keyingTransport, clientVersion, serverVersion []byte, config *ServerConfig) *handshakeTransport {
+	t := newHandshakeTransport(conn, &config.Config, clientVersion, serverVersion)
+	t.hostKeys = config.hostKeys
+	go t.readLoop()
+	go t.kexLoop()
+	return t
+}
+
+func (t *handshakeTransport) getSessionID() []byte {
+	return t.sessionID
+}
+
+// waitSession waits for the session to be established. This should be
+// the first thing to call after instantiating handshakeTransport.
+func (t *handshakeTransport) waitSession() error {
+	p, err := t.readPacket()
+	if err != nil {
+		return err
+	}
+	if p[0] != msgNewKeys {
+		return fmt.Errorf("ssh: first packet should be msgNewKeys")
+	}
+
+	return nil
+}
+
+func (t *handshakeTransport) id() string {
+	if len(t.hostKeys) > 0 {
+		return "server"
+	}
+	return "client"
+}
+
+func (t *handshakeTransport) printPacket(p []byte, write bool) {
+	action := "got"
+	if write {
+		action = "sent"
+	}
+
+	if p[0] == msgChannelData || p[0] == msgChannelExtendedData {
+		log.Printf("%s %s data (packet %d bytes)", t.id(), action, len(p))
+	} else {
+		msg, err := decode(p)
+		log.Printf("%s %s %T %v (%v)", t.id(), action, msg, msg, err)
+	}
+}
+
+func (t *handshakeTransport) readPacket() ([]byte, error) {
+	p, ok := <-t.incoming
+	if !ok {
+		return nil, t.readError
+	}
+	return p, nil
+}
+
+func (t *handshakeTransport) readLoop() {
+	first := true
+	for {
+		p, err := t.readOnePacket(first)
+		first = false
+		if err != nil {
+			t.readError = err
+			close(t.incoming)
+			break
+		}
+		if p[0] == msgIgnore || p[0] == msgDebug {
+			continue
+		}
+		t.incoming <- p
+	}
+
+	// Stop writers too.
+	t.recordWriteError(t.readError)
+
+	// Unblock the writer should it wait for this.
+	close(t.startKex)
+
+	// Don't close t.requestKex; it's also written to from writePacket.
+}
+
+func (t *handshakeTransport) pushPacket(p []byte) error {
+	if debugHandshake {
+		t.printPacket(p, true)
+	}
+	return t.conn.writePacket(p)
+}
+
+func (t *handshakeTransport) getWriteError() error {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.writeError
+}
+
+func (t *handshakeTransport) recordWriteError(err error) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if t.writeError == nil && err != nil {
+		t.writeError = err
+	}
+}
+
+func (t *handshakeTransport) requestKeyExchange() {
+	select {
+	case t.requestKex <- struct{}{}:
+	default:
+		// something already requested a kex, so do nothing.
+	}
+}
+
+func (t *handshakeTransport) resetWriteThresholds() {
+	t.writePacketsLeft = packetRekeyThreshold
+	if t.config.RekeyThreshold > 0 {
+		t.writeBytesLeft = int64(t.config.RekeyThreshold)
+	} else if t.algorithms != nil {
+		t.writeBytesLeft = t.algorithms.w.rekeyBytes()
+	} else {
+		t.writeBytesLeft = 1 << 30
+	}
+}
+
+func (t *handshakeTransport) kexLoop() {
+
+write:
+	for t.getWriteError() == nil {
+		var request *pendingKex
+		var sent bool
+
+		for request == nil || !sent {
+			var ok bool
+			select {
+			case request, ok = <-t.startKex:
+				if !ok {
+					break write
+				}
+			case <-t.requestKex:
+				break
+			}
+
+			if !sent {
+				if err := t.sendKexInit(); err != nil {
+					t.recordWriteError(err)
+					break
+				}
+				sent = true
+			}
+		}
+
+		if err := t.getWriteError(); err != nil {
+			if request != nil {
+				request.done <- err
+			}
+			break
+		}
+
+		// We're not servicing t.requestKex, but that is OK:
+		// we never block on sending to t.requestKex.
+
+		// We're not servicing t.startKex, but the remote end
+		// has just sent us a kexInitMsg, so it can't send
+		// another key change request, until we close the done
+		// channel on the pendingKex request.
+
+		err := t.enterKeyExchange(request.otherInit)
+
+		t.mu.Lock()
+		t.writeError = err
+		t.sentInitPacket = nil
+		t.sentInitMsg = nil
+
+		t.resetWriteThresholds()
+
+		// we have completed the key exchange. Since the
+		// reader is still blocked, it is safe to clear out
+		// the requestKex channel. This avoids the situation
+		// where: 1) we consumed our own request for the
+		// initial kex, and 2) the kex from the remote side
+		// caused another send on the requestKex channel,
+	clear:
+		for {
+			select {
+			case <-t.requestKex:
+				//
+			default:
+				break clear
+			}
+		}
+
+		request.done <- t.writeError
+
+		// kex finished. Push packets that we received while
+		// the kex was in progress. Don't look at t.startKex
+		// and don't increment writtenSinceKex: if we trigger
+		// another kex while we are still busy with the last
+		// one, things will become very confusing.
+		for _, p := range t.pendingPackets {
+			t.writeError = t.pushPacket(p)
+			if t.writeError != nil {
+				break
+			}
+		}
+		t.pendingPackets = t.pendingPackets[:0]
+		t.mu.Unlock()
+	}
+
+	// drain startKex channel. We don't service t.requestKex
+	// because nobody does blocking sends there.
+	go func() {
+		for init := range t.startKex {
+			init.done <- t.writeError
+		}
+	}()
+
+	// Unblock reader.
+	t.conn.Close()
+}
+
+// The protocol uses uint32 for packet counters, so we can't let them
+// reach 1<<32.  We will actually read and write more packets than
+// this, though: the other side may send more packets, and after we
+// hit this limit on writing we will send a few more packets for the
+// key exchange itself.
+const packetRekeyThreshold = (1 << 31)
+
+func (t *handshakeTransport) resetReadThresholds() {
+	t.readPacketsLeft = packetRekeyThreshold
+	if t.config.RekeyThreshold > 0 {
+		t.readBytesLeft = int64(t.config.RekeyThreshold)
+	} else if t.algorithms != nil {
+		t.readBytesLeft = t.algorithms.r.rekeyBytes()
+	} else {
+		t.readBytesLeft = 1 << 30
+	}
+}
+
+func (t *handshakeTransport) readOnePacket(first bool) ([]byte, error) {
+	p, err := t.conn.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	if t.readPacketsLeft > 0 {
+		t.readPacketsLeft--
+	} else {
+		t.requestKeyExchange()
+	}
+
+	if t.readBytesLeft > 0 {
+		t.readBytesLeft -= int64(len(p))
+	} else {
+		t.requestKeyExchange()
+	}
+
+	if debugHandshake {
+		t.printPacket(p, false)
+	}
+
+	if first && p[0] != msgKexInit {
+		return nil, fmt.Errorf("ssh: first packet should be msgKexInit")
+	}
+
+	if p[0] != msgKexInit {
+		return p, nil
+	}
+
+	firstKex := t.sessionID == nil
+
+	kex := pendingKex{
+		done:      make(chan error, 1),
+		otherInit: p,
+	}
+	t.startKex <- &kex
+	err = <-kex.done
+
+	if debugHandshake {
+		log.Printf("%s exited key exchange (first %v), err %v", t.id(), firstKex, err)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+
+	t.resetReadThresholds()
+
+	// By default, a key exchange is hidden from higher layers by
+	// translating it into msgIgnore.
+	successPacket := []byte{msgIgnore}
+	if firstKex {
+		// sendKexInit() for the first kex waits for
+		// msgNewKeys so the authentication process is
+		// guaranteed to happen over an encrypted transport.
+		successPacket = []byte{msgNewKeys}
+	}
+
+	return successPacket, nil
+}
+
+// sendKexInit sends a key change message.
+func (t *handshakeTransport) sendKexInit() error {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if t.sentInitMsg != nil {
+		// kexInits may be sent either in response to the other side,
+		// or because our side wants to initiate a key change, so we
+		// may have already sent a kexInit. In that case, don't send a
+		// second kexInit.
+		return nil
+	}
+
+	msg := &kexInitMsg{
+		KexAlgos:                t.config.KeyExchanges,
+		CiphersClientServer:     t.config.Ciphers,
+		CiphersServerClient:     t.config.Ciphers,
+		MACsClientServer:        t.config.MACs,
+		MACsServerClient:        t.config.MACs,
+		CompressionClientServer: supportedCompressions,
+		CompressionServerClient: supportedCompressions,
+	}
+	io.ReadFull(rand.Reader, msg.Cookie[:])
+
+	if len(t.hostKeys) > 0 {
+		for _, k := range t.hostKeys {
+			msg.ServerHostKeyAlgos = append(
+				msg.ServerHostKeyAlgos, k.PublicKey().Type())
+		}
+	} else {
+		msg.ServerHostKeyAlgos = t.hostKeyAlgorithms
+	}
+	packet := Marshal(msg)
+
+	// writePacket destroys the contents, so save a copy.
+	packetCopy := make([]byte, len(packet))
+	copy(packetCopy, packet)
+
+	if err := t.pushPacket(packetCopy); err != nil {
+		return err
+	}
+
+	t.sentInitMsg = msg
+	t.sentInitPacket = packet
+
+	return nil
+}
+
+func (t *handshakeTransport) writePacket(p []byte) error {
+	switch p[0] {
+	case msgKexInit:
+		return errors.New("ssh: only handshakeTransport can send kexInit")
+	case msgNewKeys:
+		return errors.New("ssh: only handshakeTransport can send newKeys")
+	}
+
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if t.writeError != nil {
+		return t.writeError
+	}
+
+	if t.sentInitMsg != nil {
+		// Copy the packet so the writer can reuse the buffer.
+		cp := make([]byte, len(p))
+		copy(cp, p)
+		t.pendingPackets = append(t.pendingPackets, cp)
+		return nil
+	}
+
+	if t.writeBytesLeft > 0 {
+		t.writeBytesLeft -= int64(len(p))
+	} else {
+		t.requestKeyExchange()
+	}
+
+	if t.writePacketsLeft > 0 {
+		t.writePacketsLeft--
+	} else {
+		t.requestKeyExchange()
+	}
+
+	if err := t.pushPacket(p); err != nil {
+		t.writeError = err
+	}
+
+	return nil
+}
+
+func (t *handshakeTransport) Close() error {
+	return t.conn.Close()
+}
+
+func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error {
+	if debugHandshake {
+		log.Printf("%s entered key exchange", t.id())
+	}
+
+	otherInit := &kexInitMsg{}
+	if err := Unmarshal(otherInitPacket, otherInit); err != nil {
+		return err
+	}
+
+	magics := handshakeMagics{
+		clientVersion: t.clientVersion,
+		serverVersion: t.serverVersion,
+		clientKexInit: otherInitPacket,
+		serverKexInit: t.sentInitPacket,
+	}
+
+	clientInit := otherInit
+	serverInit := t.sentInitMsg
+	if len(t.hostKeys) == 0 {
+		clientInit, serverInit = serverInit, clientInit
+
+		magics.clientKexInit = t.sentInitPacket
+		magics.serverKexInit = otherInitPacket
+	}
+
+	var err error
+	t.algorithms, err = findAgreedAlgorithms(clientInit, serverInit)
+	if err != nil {
+		return err
+	}
+
+	// We don't send FirstKexFollows, but we handle receiving it.
+	//
+	// RFC 4253 section 7 defines the kex and the agreement method for
+	// first_kex_packet_follows. It states that the guessed packet
+	// should be ignored if the "kex algorithm and/or the host
+	// key algorithm is guessed wrong (server and client have
+	// different preferred algorithm), or if any of the other
+	// algorithms cannot be agreed upon". The other algorithms have
+	// already been checked above so the kex algorithm and host key
+	// algorithm are checked here.
+	if otherInit.FirstKexFollows && (clientInit.KexAlgos[0] != serverInit.KexAlgos[0] || clientInit.ServerHostKeyAlgos[0] != serverInit.ServerHostKeyAlgos[0]) {
+		// other side sent a kex message for the wrong algorithm,
+		// which we have to ignore.
+		if _, err := t.conn.readPacket(); err != nil {
+			return err
+		}
+	}
+
+	kex, ok := kexAlgoMap[t.algorithms.kex]
+	if !ok {
+		return fmt.Errorf("ssh: unexpected key exchange algorithm %v", t.algorithms.kex)
+	}
+
+	var result *kexResult
+	if len(t.hostKeys) > 0 {
+		result, err = t.server(kex, t.algorithms, &magics)
+	} else {
+		result, err = t.client(kex, t.algorithms, &magics)
+	}
+
+	if err != nil {
+		return err
+	}
+
+	if t.sessionID == nil {
+		t.sessionID = result.H
+	}
+	result.SessionID = t.sessionID
+
+	if err := t.conn.prepareKeyChange(t.algorithms, result); err != nil {
+		return err
+	}
+	if err = t.conn.writePacket([]byte{msgNewKeys}); err != nil {
+		return err
+	}
+	if packet, err := t.conn.readPacket(); err != nil {
+		return err
+	} else if packet[0] != msgNewKeys {
+		return unexpectedMessageError(msgNewKeys, packet[0])
+	}
+
+	return nil
+}
+
+func (t *handshakeTransport) server(kex kexAlgorithm, algs *algorithms, magics *handshakeMagics) (*kexResult, error) {
+	var hostKey Signer
+	for _, k := range t.hostKeys {
+		if algs.hostKey == k.PublicKey().Type() {
+			hostKey = k
+		}
+	}
+
+	r, err := kex.Server(t.conn, t.config.Rand, magics, hostKey)
+	return r, err
+}
+
+func (t *handshakeTransport) client(kex kexAlgorithm, algs *algorithms, magics *handshakeMagics) (*kexResult, error) {
+	result, err := kex.Client(t.conn, t.config.Rand, magics)
+	if err != nil {
+		return nil, err
+	}
+
+	hostKey, err := ParsePublicKey(result.HostKey)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := verifyHostKeySignature(hostKey, result); err != nil {
+		return nil, err
+	}
+
+	err = t.hostKeyCallback(t.dialAddress, t.remoteAddr, hostKey)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}

vendor/golang.org/x/crypto/ssh/kex.go

@@ -0,0 +1,540 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/subtle"
+	"errors"
+	"io"
+	"math/big"
+
+	"golang.org/x/crypto/curve25519"
+)
+
+const (
+	kexAlgoDH1SHA1          = "diffie-hellman-group1-sha1"
+	kexAlgoDH14SHA1         = "diffie-hellman-group14-sha1"
+	kexAlgoECDH256          = "ecdh-sha2-nistp256"
+	kexAlgoECDH384          = "ecdh-sha2-nistp384"
+	kexAlgoECDH521          = "ecdh-sha2-nistp521"
+	kexAlgoCurve25519SHA256 = "curve25519-sha256@libssh.org"
+)
+
+// kexResult captures the outcome of a key exchange.
+type kexResult struct {
+	// Session hash. See also RFC 4253, section 8.
+	H []byte
+
+	// Shared secret. See also RFC 4253, section 8.
+	K []byte
+
+	// Host key as hashed into H.
+	HostKey []byte
+
+	// Signature of H.
+	Signature []byte
+
+	// A cryptographic hash function that matches the security
+	// level of the key exchange algorithm. It is used for
+	// calculating H, and for deriving keys from H and K.
+	Hash crypto.Hash
+
+	// The session ID, which is the first H computed. This is used
+	// to derive key material inside the transport.
+	SessionID []byte
+}
+
+// handshakeMagics contains data that is always included in the
+// session hash.
+type handshakeMagics struct {
+	clientVersion, serverVersion []byte
+	clientKexInit, serverKexInit []byte
+}
+
+func (m *handshakeMagics) write(w io.Writer) {
+	writeString(w, m.clientVersion)
+	writeString(w, m.serverVersion)
+	writeString(w, m.clientKexInit)
+	writeString(w, m.serverKexInit)
+}
+
+// kexAlgorithm abstracts different key exchange algorithms.
+type kexAlgorithm interface {
+	// Server runs server-side key agreement, signing the result
+	// with a hostkey.
+	Server(p packetConn, rand io.Reader, magics *handshakeMagics, s Signer) (*kexResult, error)
+
+	// Client runs the client-side key agreement. Caller is
+	// responsible for verifying the host key signature.
+	Client(p packetConn, rand io.Reader, magics *handshakeMagics) (*kexResult, error)
+}
+
+// dhGroup is a multiplicative group suitable for implementing Diffie-Hellman key agreement.
+type dhGroup struct {
+	g, p, pMinus1 *big.Int
+}
+
+func (group *dhGroup) diffieHellman(theirPublic, myPrivate *big.Int) (*big.Int, error) {
+	if theirPublic.Cmp(bigOne) <= 0 || theirPublic.Cmp(group.pMinus1) >= 0 {
+		return nil, errors.New("ssh: DH parameter out of bounds")
+	}
+	return new(big.Int).Exp(theirPublic, myPrivate, group.p), nil
+}
+
+func (group *dhGroup) Client(c packetConn, randSource io.Reader, magics *handshakeMagics) (*kexResult, error) {
+	hashFunc := crypto.SHA1
+
+	var x *big.Int
+	for {
+		var err error
+		if x, err = rand.Int(randSource, group.pMinus1); err != nil {
+			return nil, err
+		}
+		if x.Sign() > 0 {
+			break
+		}
+	}
+
+	X := new(big.Int).Exp(group.g, x, group.p)
+	kexDHInit := kexDHInitMsg{
+		X: X,
+	}
+	if err := c.writePacket(Marshal(&kexDHInit)); err != nil {
+		return nil, err
+	}
+
+	packet, err := c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var kexDHReply kexDHReplyMsg
+	if err = Unmarshal(packet, &kexDHReply); err != nil {
+		return nil, err
+	}
+
+	kInt, err := group.diffieHellman(kexDHReply.Y, x)
+	if err != nil {
+		return nil, err
+	}
+
+	h := hashFunc.New()
+	magics.write(h)
+	writeString(h, kexDHReply.HostKey)
+	writeInt(h, X)
+	writeInt(h, kexDHReply.Y)
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	return &kexResult{
+		H:         h.Sum(nil),
+		K:         K,
+		HostKey:   kexDHReply.HostKey,
+		Signature: kexDHReply.Signature,
+		Hash:      crypto.SHA1,
+	}, nil
+}
+
+func (group *dhGroup) Server(c packetConn, randSource io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
+	hashFunc := crypto.SHA1
+	packet, err := c.readPacket()
+	if err != nil {
+		return
+	}
+	var kexDHInit kexDHInitMsg
+	if err = Unmarshal(packet, &kexDHInit); err != nil {
+		return
+	}
+
+	var y *big.Int
+	for {
+		if y, err = rand.Int(randSource, group.pMinus1); err != nil {
+			return
+		}
+		if y.Sign() > 0 {
+			break
+		}
+	}
+
+	Y := new(big.Int).Exp(group.g, y, group.p)
+	kInt, err := group.diffieHellman(kexDHInit.X, y)
+	if err != nil {
+		return nil, err
+	}
+
+	hostKeyBytes := priv.PublicKey().Marshal()
+
+	h := hashFunc.New()
+	magics.write(h)
+	writeString(h, hostKeyBytes)
+	writeInt(h, kexDHInit.X)
+	writeInt(h, Y)
+
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	H := h.Sum(nil)
+
+	// H is already a hash, but the hostkey signing will apply its
+	// own key-specific hash algorithm.
+	sig, err := signAndMarshal(priv, randSource, H)
+	if err != nil {
+		return nil, err
+	}
+
+	kexDHReply := kexDHReplyMsg{
+		HostKey:   hostKeyBytes,
+		Y:         Y,
+		Signature: sig,
+	}
+	packet = Marshal(&kexDHReply)
+
+	err = c.writePacket(packet)
+	return &kexResult{
+		H:         H,
+		K:         K,
+		HostKey:   hostKeyBytes,
+		Signature: sig,
+		Hash:      crypto.SHA1,
+	}, nil
+}
+
+// ecdh performs Elliptic Curve Diffie-Hellman key exchange as
+// described in RFC 5656, section 4.
+type ecdh struct {
+	curve elliptic.Curve
+}
+
+func (kex *ecdh) Client(c packetConn, rand io.Reader, magics *handshakeMagics) (*kexResult, error) {
+	ephKey, err := ecdsa.GenerateKey(kex.curve, rand)
+	if err != nil {
+		return nil, err
+	}
+
+	kexInit := kexECDHInitMsg{
+		ClientPubKey: elliptic.Marshal(kex.curve, ephKey.PublicKey.X, ephKey.PublicKey.Y),
+	}
+
+	serialized := Marshal(&kexInit)
+	if err := c.writePacket(serialized); err != nil {
+		return nil, err
+	}
+
+	packet, err := c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var reply kexECDHReplyMsg
+	if err = Unmarshal(packet, &reply); err != nil {
+		return nil, err
+	}
+
+	x, y, err := unmarshalECKey(kex.curve, reply.EphemeralPubKey)
+	if err != nil {
+		return nil, err
+	}
+
+	// generate shared secret
+	secret, _ := kex.curve.ScalarMult(x, y, ephKey.D.Bytes())
+
+	h := ecHash(kex.curve).New()
+	magics.write(h)
+	writeString(h, reply.HostKey)
+	writeString(h, kexInit.ClientPubKey)
+	writeString(h, reply.EphemeralPubKey)
+	K := make([]byte, intLength(secret))
+	marshalInt(K, secret)
+	h.Write(K)
+
+	return &kexResult{
+		H:         h.Sum(nil),
+		K:         K,
+		HostKey:   reply.HostKey,
+		Signature: reply.Signature,
+		Hash:      ecHash(kex.curve),
+	}, nil
+}
+
+// unmarshalECKey parses and checks an EC key.
+func unmarshalECKey(curve elliptic.Curve, pubkey []byte) (x, y *big.Int, err error) {
+	x, y = elliptic.Unmarshal(curve, pubkey)
+	if x == nil {
+		return nil, nil, errors.New("ssh: elliptic.Unmarshal failure")
+	}
+	if !validateECPublicKey(curve, x, y) {
+		return nil, nil, errors.New("ssh: public key not on curve")
+	}
+	return x, y, nil
+}
+
+// validateECPublicKey checks that the point is a valid public key for
+// the given curve. See [SEC1], 3.2.2
+func validateECPublicKey(curve elliptic.Curve, x, y *big.Int) bool {
+	if x.Sign() == 0 && y.Sign() == 0 {
+		return false
+	}
+
+	if x.Cmp(curve.Params().P) >= 0 {
+		return false
+	}
+
+	if y.Cmp(curve.Params().P) >= 0 {
+		return false
+	}
+
+	if !curve.IsOnCurve(x, y) {
+		return false
+	}
+
+	// We don't check if N * PubKey == 0, since
+	//
+	// - the NIST curves have cofactor = 1, so this is implicit.
+	// (We don't foresee an implementation that supports non NIST
+	// curves)
+	//
+	// - for ephemeral keys, we don't need to worry about small
+	// subgroup attacks.
+	return true
+}
+
+func (kex *ecdh) Server(c packetConn, rand io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
+	packet, err := c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var kexECDHInit kexECDHInitMsg
+	if err = Unmarshal(packet, &kexECDHInit); err != nil {
+		return nil, err
+	}
+
+	clientX, clientY, err := unmarshalECKey(kex.curve, kexECDHInit.ClientPubKey)
+	if err != nil {
+		return nil, err
+	}
+
+	// We could cache this key across multiple users/multiple
+	// connection attempts, but the benefit is small. OpenSSH
+	// generates a new key for each incoming connection.
+	ephKey, err := ecdsa.GenerateKey(kex.curve, rand)
+	if err != nil {
+		return nil, err
+	}
+
+	hostKeyBytes := priv.PublicKey().Marshal()
+
+	serializedEphKey := elliptic.Marshal(kex.curve, ephKey.PublicKey.X, ephKey.PublicKey.Y)
+
+	// generate shared secret
+	secret, _ := kex.curve.ScalarMult(clientX, clientY, ephKey.D.Bytes())
+
+	h := ecHash(kex.curve).New()
+	magics.write(h)
+	writeString(h, hostKeyBytes)
+	writeString(h, kexECDHInit.ClientPubKey)
+	writeString(h, serializedEphKey)
+
+	K := make([]byte, intLength(secret))
+	marshalInt(K, secret)
+	h.Write(K)
+
+	H := h.Sum(nil)
+
+	// H is already a hash, but the hostkey signing will apply its
+	// own key-specific hash algorithm.
+	sig, err := signAndMarshal(priv, rand, H)
+	if err != nil {
+		return nil, err
+	}
+
+	reply := kexECDHReplyMsg{
+		EphemeralPubKey: serializedEphKey,
+		HostKey:         hostKeyBytes,
+		Signature:       sig,
+	}
+
+	serialized := Marshal(&reply)
+	if err := c.writePacket(serialized); err != nil {
+		return nil, err
+	}
+
+	return &kexResult{
+		H:         H,
+		K:         K,
+		HostKey:   reply.HostKey,
+		Signature: sig,
+		Hash:      ecHash(kex.curve),
+	}, nil
+}
+
+var kexAlgoMap = map[string]kexAlgorithm{}
+
+func init() {
+	// This is the group called diffie-hellman-group1-sha1 in RFC
+	// 4253 and Oakley Group 2 in RFC 2409.
+	p, _ := new(big.Int).SetString("FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF", 16)
+	kexAlgoMap[kexAlgoDH1SHA1] = &dhGroup{
+		g:       new(big.Int).SetInt64(2),
+		p:       p,
+		pMinus1: new(big.Int).Sub(p, bigOne),
+	}
+
+	// This is the group called diffie-hellman-group14-sha1 in RFC
+	// 4253 and Oakley Group 14 in RFC 3526.
+	p, _ = new(big.Int).SetString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
+
+	kexAlgoMap[kexAlgoDH14SHA1] = &dhGroup{
+		g:       new(big.Int).SetInt64(2),
+		p:       p,
+		pMinus1: new(big.Int).Sub(p, bigOne),
+	}
+
+	kexAlgoMap[kexAlgoECDH521] = &ecdh{elliptic.P521()}
+	kexAlgoMap[kexAlgoECDH384] = &ecdh{elliptic.P384()}
+	kexAlgoMap[kexAlgoECDH256] = &ecdh{elliptic.P256()}
+	kexAlgoMap[kexAlgoCurve25519SHA256] = &curve25519sha256{}
+}
+
+// curve25519sha256 implements the curve25519-sha256@libssh.org key
+// agreement protocol, as described in
+// https://git.libssh.org/projects/libssh.git/tree/doc/curve25519-sha256@libssh.org.txt
+type curve25519sha256 struct{}
+
+type curve25519KeyPair struct {
+	priv [32]byte
+	pub  [32]byte
+}
+
+func (kp *curve25519KeyPair) generate(rand io.Reader) error {
+	if _, err := io.ReadFull(rand, kp.priv[:]); err != nil {
+		return err
+	}
+	curve25519.ScalarBaseMult(&kp.pub, &kp.priv)
+	return nil
+}
+
+// curve25519Zeros is just an array of 32 zero bytes so that we have something
+// convenient to compare against in order to reject curve25519 points with the
+// wrong order.
+var curve25519Zeros [32]byte
+
+func (kex *curve25519sha256) Client(c packetConn, rand io.Reader, magics *handshakeMagics) (*kexResult, error) {
+	var kp curve25519KeyPair
+	if err := kp.generate(rand); err != nil {
+		return nil, err
+	}
+	if err := c.writePacket(Marshal(&kexECDHInitMsg{kp.pub[:]})); err != nil {
+		return nil, err
+	}
+
+	packet, err := c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var reply kexECDHReplyMsg
+	if err = Unmarshal(packet, &reply); err != nil {
+		return nil, err
+	}
+	if len(reply.EphemeralPubKey) != 32 {
+		return nil, errors.New("ssh: peer's curve25519 public value has wrong length")
+	}
+
+	var servPub, secret [32]byte
+	copy(servPub[:], reply.EphemeralPubKey)
+	curve25519.ScalarMult(&secret, &kp.priv, &servPub)
+	if subtle.ConstantTimeCompare(secret[:], curve25519Zeros[:]) == 1 {
+		return nil, errors.New("ssh: peer's curve25519 public value has wrong order")
+	}
+
+	h := crypto.SHA256.New()
+	magics.write(h)
+	writeString(h, reply.HostKey)
+	writeString(h, kp.pub[:])
+	writeString(h, reply.EphemeralPubKey)
+
+	kInt := new(big.Int).SetBytes(secret[:])
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	return &kexResult{
+		H:         h.Sum(nil),
+		K:         K,
+		HostKey:   reply.HostKey,
+		Signature: reply.Signature,
+		Hash:      crypto.SHA256,
+	}, nil
+}
+
+func (kex *curve25519sha256) Server(c packetConn, rand io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
+	packet, err := c.readPacket()
+	if err != nil {
+		return
+	}
+	var kexInit kexECDHInitMsg
+	if err = Unmarshal(packet, &kexInit); err != nil {
+		return
+	}
+
+	if len(kexInit.ClientPubKey) != 32 {
+		return nil, errors.New("ssh: peer's curve25519 public value has wrong length")
+	}
+
+	var kp curve25519KeyPair
+	if err := kp.generate(rand); err != nil {
+		return nil, err
+	}
+
+	var clientPub, secret [32]byte
+	copy(clientPub[:], kexInit.ClientPubKey)
+	curve25519.ScalarMult(&secret, &kp.priv, &clientPub)
+	if subtle.ConstantTimeCompare(secret[:], curve25519Zeros[:]) == 1 {
+		return nil, errors.New("ssh: peer's curve25519 public value has wrong order")
+	}
+
+	hostKeyBytes := priv.PublicKey().Marshal()
+
+	h := crypto.SHA256.New()
+	magics.write(h)
+	writeString(h, hostKeyBytes)
+	writeString(h, kexInit.ClientPubKey)
+	writeString(h, kp.pub[:])
+
+	kInt := new(big.Int).SetBytes(secret[:])
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	H := h.Sum(nil)
+
+	sig, err := signAndMarshal(priv, rand, H)
+	if err != nil {
+		return nil, err
+	}
+
+	reply := kexECDHReplyMsg{
+		EphemeralPubKey: kp.pub[:],
+		HostKey:         hostKeyBytes,
+		Signature:       sig,
+	}
+	if err := c.writePacket(Marshal(&reply)); err != nil {
+		return nil, err
+	}
+	return &kexResult{
+		H:         H,
+		K:         K,
+		HostKey:   hostKeyBytes,
+		Signature: sig,
+		Hash:      crypto.SHA256,
+	}, nil
+}

vendor/golang.org/x/crypto/ssh/mac.go

@@ -0,0 +1,61 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+// Message authentication support
+
+import (
+	"crypto/hmac"
+	"crypto/sha1"
+	"crypto/sha256"
+	"hash"
+)
+
+type macMode struct {
+	keySize int
+	etm     bool
+	new     func(key []byte) hash.Hash
+}
+
+// truncatingMAC wraps around a hash.Hash and truncates the output digest to
+// a given size.
+type truncatingMAC struct {
+	length int
+	hmac   hash.Hash
+}
+
+func (t truncatingMAC) Write(data []byte) (int, error) {
+	return t.hmac.Write(data)
+}
+
+func (t truncatingMAC) Sum(in []byte) []byte {
+	out := t.hmac.Sum(in)
+	return out[:len(in)+t.length]
+}
+
+func (t truncatingMAC) Reset() {
+	t.hmac.Reset()
+}
+
+func (t truncatingMAC) Size() int {
+	return t.length
+}
+
+func (t truncatingMAC) BlockSize() int { return t.hmac.BlockSize() }
+
+var macModes = map[string]*macMode{
+	"hmac-sha2-256-etm@openssh.com": {32, true, func(key []byte) hash.Hash {
+		return hmac.New(sha256.New, key)
+	}},
+	"hmac-sha2-256": {32, false, func(key []byte) hash.Hash {
+		return hmac.New(sha256.New, key)
+	}},
+	"hmac-sha1": {20, false, func(key []byte) hash.Hash {
+		return hmac.New(sha1.New, key)
+	}},
+	"hmac-sha1-96": {20, false, func(key []byte) hash.Hash {
+		return truncatingMAC{12, hmac.New(sha1.New, key)}
+	}},
+}

vendor/golang.org/x/crypto/ssh/messages.go

@@ -0,0 +1,766 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"math/big"
+	"reflect"
+	"strconv"
+	"strings"
+)
+
+// These are SSH message type numbers. They are scattered around several
+// documents but many were taken from [SSH-PARAMETERS].
+const (
+	msgIgnore        = 2
+	msgUnimplemented = 3
+	msgDebug         = 4
+	msgNewKeys       = 21
+)
+
+// SSH messages:
+//
+// These structures mirror the wire format of the corresponding SSH messages.
+// They are marshaled using reflection with the marshal and unmarshal functions
+// in this file. The only wrinkle is that a final member of type []byte with a
+// ssh tag of "rest" receives the remainder of a packet when unmarshaling.
+
+// See RFC 4253, section 11.1.
+const msgDisconnect = 1
+
+// disconnectMsg is the message that signals a disconnect. It is also
+// the error type returned from mux.Wait()
+type disconnectMsg struct {
+	Reason   uint32 `sshtype:"1"`
+	Message  string
+	Language string
+}
+
+func (d *disconnectMsg) Error() string {
+	return fmt.Sprintf("ssh: disconnect, reason %d: %s", d.Reason, d.Message)
+}
+
+// See RFC 4253, section 7.1.
+const msgKexInit = 20
+
+type kexInitMsg struct {
+	Cookie                  [16]byte `sshtype:"20"`
+	KexAlgos                []string
+	ServerHostKeyAlgos      []string
+	CiphersClientServer     []string
+	CiphersServerClient     []string
+	MACsClientServer        []string
+	MACsServerClient        []string
+	CompressionClientServer []string
+	CompressionServerClient []string
+	LanguagesClientServer   []string
+	LanguagesServerClient   []string
+	FirstKexFollows         bool
+	Reserved                uint32
+}
+
+// See RFC 4253, section 8.
+
+// Diffie-Helman
+const msgKexDHInit = 30
+
+type kexDHInitMsg struct {
+	X *big.Int `sshtype:"30"`
+}
+
+const msgKexECDHInit = 30
+
+type kexECDHInitMsg struct {
+	ClientPubKey []byte `sshtype:"30"`
+}
+
+const msgKexECDHReply = 31
+
+type kexECDHReplyMsg struct {
+	HostKey         []byte `sshtype:"31"`
+	EphemeralPubKey []byte
+	Signature       []byte
+}
+
+const msgKexDHReply = 31
+
+type kexDHReplyMsg struct {
+	HostKey   []byte `sshtype:"31"`
+	Y         *big.Int
+	Signature []byte
+}
+
+// See RFC 4253, section 10.
+const msgServiceRequest = 5
+
+type serviceRequestMsg struct {
+	Service string `sshtype:"5"`
+}
+
+// See RFC 4253, section 10.
+const msgServiceAccept = 6
+
+type serviceAcceptMsg struct {
+	Service string `sshtype:"6"`
+}
+
+// See RFC 4252, section 5.
+const msgUserAuthRequest = 50
+
+type userAuthRequestMsg struct {
+	User    string `sshtype:"50"`
+	Service string
+	Method  string
+	Payload []byte `ssh:"rest"`
+}
+
+// Used for debug printouts of packets.
+type userAuthSuccessMsg struct {
+}
+
+// See RFC 4252, section 5.1
+const msgUserAuthFailure = 51
+
+type userAuthFailureMsg struct {
+	Methods        []string `sshtype:"51"`
+	PartialSuccess bool
+}
+
+// See RFC 4252, section 5.1
+const msgUserAuthSuccess = 52
+
+// See RFC 4252, section 5.4
+const msgUserAuthBanner = 53
+
+type userAuthBannerMsg struct {
+	Message string `sshtype:"53"`
+	// unused, but required to allow message parsing
+	Language string
+}
+
+// See RFC 4256, section 3.2
+const msgUserAuthInfoRequest = 60
+const msgUserAuthInfoResponse = 61
+
+type userAuthInfoRequestMsg struct {
+	User               string `sshtype:"60"`
+	Instruction        string
+	DeprecatedLanguage string
+	NumPrompts         uint32
+	Prompts            []byte `ssh:"rest"`
+}
+
+// See RFC 4254, section 5.1.
+const msgChannelOpen = 90
+
+type channelOpenMsg struct {
+	ChanType         string `sshtype:"90"`
+	PeersId          uint32
+	PeersWindow      uint32
+	MaxPacketSize    uint32
+	TypeSpecificData []byte `ssh:"rest"`
+}
+
+const msgChannelExtendedData = 95
+const msgChannelData = 94
+
+// Used for debug print outs of packets.
+type channelDataMsg struct {
+	PeersId uint32 `sshtype:"94"`
+	Length  uint32
+	Rest    []byte `ssh:"rest"`
+}
+
+// See RFC 4254, section 5.1.
+const msgChannelOpenConfirm = 91
+
+type channelOpenConfirmMsg struct {
+	PeersId          uint32 `sshtype:"91"`
+	MyId             uint32
+	MyWindow         uint32
+	MaxPacketSize    uint32
+	TypeSpecificData []byte `ssh:"rest"`
+}
+
+// See RFC 4254, section 5.1.
+const msgChannelOpenFailure = 92
+
+type channelOpenFailureMsg struct {
+	PeersId  uint32 `sshtype:"92"`
+	Reason   RejectionReason
+	Message  string
+	Language string
+}
+
+const msgChannelRequest = 98
+
+type channelRequestMsg struct {
+	PeersId             uint32 `sshtype:"98"`
+	Request             string
+	WantReply           bool
+	RequestSpecificData []byte `ssh:"rest"`
+}
+
+// See RFC 4254, section 5.4.
+const msgChannelSuccess = 99
+
+type channelRequestSuccessMsg struct {
+	PeersId uint32 `sshtype:"99"`
+}
+
+// See RFC 4254, section 5.4.
+const msgChannelFailure = 100
+
+type channelRequestFailureMsg struct {
+	PeersId uint32 `sshtype:"100"`
+}
+
+// See RFC 4254, section 5.3
+const msgChannelClose = 97
+
+type channelCloseMsg struct {
+	PeersId uint32 `sshtype:"97"`
+}
+
+// See RFC 4254, section 5.3
+const msgChannelEOF = 96
+
+type channelEOFMsg struct {
+	PeersId uint32 `sshtype:"96"`
+}
+
+// See RFC 4254, section 4
+const msgGlobalRequest = 80
+
+type globalRequestMsg struct {
+	Type      string `sshtype:"80"`
+	WantReply bool
+	Data      []byte `ssh:"rest"`
+}
+
+// See RFC 4254, section 4
+const msgRequestSuccess = 81
+
+type globalRequestSuccessMsg struct {
+	Data []byte `ssh:"rest" sshtype:"81"`
+}
+
+// See RFC 4254, section 4
+const msgRequestFailure = 82
+
+type globalRequestFailureMsg struct {
+	Data []byte `ssh:"rest" sshtype:"82"`
+}
+
+// See RFC 4254, section 5.2
+const msgChannelWindowAdjust = 93
+
+type windowAdjustMsg struct {
+	PeersId         uint32 `sshtype:"93"`
+	AdditionalBytes uint32
+}
+
+// See RFC 4252, section 7
+const msgUserAuthPubKeyOk = 60
+
+type userAuthPubKeyOkMsg struct {
+	Algo   string `sshtype:"60"`
+	PubKey []byte
+}
+
+// typeTags returns the possible type bytes for the given reflect.Type, which
+// should be a struct. The possible values are separated by a '|' character.
+func typeTags(structType reflect.Type) (tags []byte) {
+	tagStr := structType.Field(0).Tag.Get("sshtype")
+
+	for _, tag := range strings.Split(tagStr, "|") {
+		i, err := strconv.Atoi(tag)
+		if err == nil {
+			tags = append(tags, byte(i))
+		}
+	}
+
+	return tags
+}
+
+func fieldError(t reflect.Type, field int, problem string) error {
+	if problem != "" {
+		problem = ": " + problem
+	}
+	return fmt.Errorf("ssh: unmarshal error for field %s of type %s%s", t.Field(field).Name, t.Name(), problem)
+}
+
+var errShortRead = errors.New("ssh: short read")
+
+// Unmarshal parses data in SSH wire format into a structure. The out
+// argument should be a pointer to struct. If the first member of the
+// struct has the "sshtype" tag set to a '|'-separated set of numbers
+// in decimal, the packet must start with one of those numbers. In
+// case of error, Unmarshal returns a ParseError or
+// UnexpectedMessageError.
+func Unmarshal(data []byte, out interface{}) error {
+	v := reflect.ValueOf(out).Elem()
+	structType := v.Type()
+	expectedTypes := typeTags(structType)
+
+	var expectedType byte
+	if len(expectedTypes) > 0 {
+		expectedType = expectedTypes[0]
+	}
+
+	if len(data) == 0 {
+		return parseError(expectedType)
+	}
+
+	if len(expectedTypes) > 0 {
+		goodType := false
+		for _, e := range expectedTypes {
+			if e > 0 && data[0] == e {
+				goodType = true
+				break
+			}
+		}
+		if !goodType {
+			return fmt.Errorf("ssh: unexpected message type %d (expected one of %v)", data[0], expectedTypes)
+		}
+		data = data[1:]
+	}
+
+	var ok bool
+	for i := 0; i < v.NumField(); i++ {
+		field := v.Field(i)
+		t := field.Type()
+		switch t.Kind() {
+		case reflect.Bool:
+			if len(data) < 1 {
+				return errShortRead
+			}
+			field.SetBool(data[0] != 0)
+			data = data[1:]
+		case reflect.Array:
+			if t.Elem().Kind() != reflect.Uint8 {
+				return fieldError(structType, i, "array of unsupported type")
+			}
+			if len(data) < t.Len() {
+				return errShortRead
+			}
+			for j, n := 0, t.Len(); j < n; j++ {
+				field.Index(j).Set(reflect.ValueOf(data[j]))
+			}
+			data = data[t.Len():]
+		case reflect.Uint64:
+			var u64 uint64
+			if u64, data, ok = parseUint64(data); !ok {
+				return errShortRead
+			}
+			field.SetUint(u64)
+		case reflect.Uint32:
+			var u32 uint32
+			if u32, data, ok = parseUint32(data); !ok {
+				return errShortRead
+			}
+			field.SetUint(uint64(u32))
+		case reflect.Uint8:
+			if len(data) < 1 {
+				return errShortRead
+			}
+			field.SetUint(uint64(data[0]))
+			data = data[1:]
+		case reflect.String:
+			var s []byte
+			if s, data, ok = parseString(data); !ok {
+				return fieldError(structType, i, "")
+			}
+			field.SetString(string(s))
+		case reflect.Slice:
+			switch t.Elem().Kind() {
+			case reflect.Uint8:
+				if structType.Field(i).Tag.Get("ssh") == "rest" {
+					field.Set(reflect.ValueOf(data))
+					data = nil
+				} else {
+					var s []byte
+					if s, data, ok = parseString(data); !ok {
+						return errShortRead
+					}
+					field.Set(reflect.ValueOf(s))
+				}
+			case reflect.String:
+				var nl []string
+				if nl, data, ok = parseNameList(data); !ok {
+					return errShortRead
+				}
+				field.Set(reflect.ValueOf(nl))
+			default:
+				return fieldError(structType, i, "slice of unsupported type")
+			}
+		case reflect.Ptr:
+			if t == bigIntType {
+				var n *big.Int
+				if n, data, ok = parseInt(data); !ok {
+					return errShortRead
+				}
+				field.Set(reflect.ValueOf(n))
+			} else {
+				return fieldError(structType, i, "pointer to unsupported type")
+			}
+		default:
+			return fieldError(structType, i, fmt.Sprintf("unsupported type: %v", t))
+		}
+	}
+
+	if len(data) != 0 {
+		return parseError(expectedType)
+	}
+
+	return nil
+}
+
+// Marshal serializes the message in msg to SSH wire format.  The msg
+// argument should be a struct or pointer to struct. If the first
+// member has the "sshtype" tag set to a number in decimal, that
+// number is prepended to the result. If the last of member has the
+// "ssh" tag set to "rest", its contents are appended to the output.
+func Marshal(msg interface{}) []byte {
+	out := make([]byte, 0, 64)
+	return marshalStruct(out, msg)
+}
+
+func marshalStruct(out []byte, msg interface{}) []byte {
+	v := reflect.Indirect(reflect.ValueOf(msg))
+	msgTypes := typeTags(v.Type())
+	if len(msgTypes) > 0 {
+		out = append(out, msgTypes[0])
+	}
+
+	for i, n := 0, v.NumField(); i < n; i++ {
+		field := v.Field(i)
+		switch t := field.Type(); t.Kind() {
+		case reflect.Bool:
+			var v uint8
+			if field.Bool() {
+				v = 1
+			}
+			out = append(out, v)
+		case reflect.Array:
+			if t.Elem().Kind() != reflect.Uint8 {
+				panic(fmt.Sprintf("array of non-uint8 in field %d: %T", i, field.Interface()))
+			}
+			for j, l := 0, t.Len(); j < l; j++ {
+				out = append(out, uint8(field.Index(j).Uint()))
+			}
+		case reflect.Uint32:
+			out = appendU32(out, uint32(field.Uint()))
+		case reflect.Uint64:
+			out = appendU64(out, uint64(field.Uint()))
+		case reflect.Uint8:
+			out = append(out, uint8(field.Uint()))
+		case reflect.String:
+			s := field.String()
+			out = appendInt(out, len(s))
+			out = append(out, s...)
+		case reflect.Slice:
+			switch t.Elem().Kind() {
+			case reflect.Uint8:
+				if v.Type().Field(i).Tag.Get("ssh") != "rest" {
+					out = appendInt(out, field.Len())
+				}
+				out = append(out, field.Bytes()...)
+			case reflect.String:
+				offset := len(out)
+				out = appendU32(out, 0)
+				if n := field.Len(); n > 0 {
+					for j := 0; j < n; j++ {
+						f := field.Index(j)
+						if j != 0 {
+							out = append(out, ',')
+						}
+						out = append(out, f.String()...)
+					}
+					// overwrite length value
+					binary.BigEndian.PutUint32(out[offset:], uint32(len(out)-offset-4))
+				}
+			default:
+				panic(fmt.Sprintf("slice of unknown type in field %d: %T", i, field.Interface()))
+			}
+		case reflect.Ptr:
+			if t == bigIntType {
+				var n *big.Int
+				nValue := reflect.ValueOf(&n)
+				nValue.Elem().Set(field)
+				needed := intLength(n)
+				oldLength := len(out)
+
+				if cap(out)-len(out) < needed {
+					newOut := make([]byte, len(out), 2*(len(out)+needed))
+					copy(newOut, out)
+					out = newOut
+				}
+				out = out[:oldLength+needed]
+				marshalInt(out[oldLength:], n)
+			} else {
+				panic(fmt.Sprintf("pointer to unknown type in field %d: %T", i, field.Interface()))
+			}
+		}
+	}
+
+	return out
+}
+
+var bigOne = big.NewInt(1)
+
+func parseString(in []byte) (out, rest []byte, ok bool) {
+	if len(in) < 4 {
+		return
+	}
+	length := binary.BigEndian.Uint32(in)
+	in = in[4:]
+	if uint32(len(in)) < length {
+		return
+	}
+	out = in[:length]
+	rest = in[length:]
+	ok = true
+	return
+}
+
+var (
+	comma         = []byte{','}
+	emptyNameList = []string{}
+)
+
+func parseNameList(in []byte) (out []string, rest []byte, ok bool) {
+	contents, rest, ok := parseString(in)
+	if !ok {
+		return
+	}
+	if len(contents) == 0 {
+		out = emptyNameList
+		return
+	}
+	parts := bytes.Split(contents, comma)
+	out = make([]string, len(parts))
+	for i, part := range parts {
+		out[i] = string(part)
+	}
+	return
+}
+
+func parseInt(in []byte) (out *big.Int, rest []byte, ok bool) {
+	contents, rest, ok := parseString(in)
+	if !ok {
+		return
+	}
+	out = new(big.Int)
+
+	if len(contents) > 0 && contents[0]&0x80 == 0x80 {
+		// This is a negative number
+		notBytes := make([]byte, len(contents))
+		for i := range notBytes {
+			notBytes[i] = ^contents[i]
+		}
+		out.SetBytes(notBytes)
+		out.Add(out, bigOne)
+		out.Neg(out)
+	} else {
+		// Positive number
+		out.SetBytes(contents)
+	}
+	ok = true
+	return
+}
+
+func parseUint32(in []byte) (uint32, []byte, bool) {
+	if len(in) < 4 {
+		return 0, nil, false
+	}
+	return binary.BigEndian.Uint32(in), in[4:], true
+}
+
+func parseUint64(in []byte) (uint64, []byte, bool) {
+	if len(in) < 8 {
+		return 0, nil, false
+	}
+	return binary.BigEndian.Uint64(in), in[8:], true
+}
+
+func intLength(n *big.Int) int {
+	length := 4 /* length bytes */
+	if n.Sign() < 0 {
+		nMinus1 := new(big.Int).Neg(n)
+		nMinus1.Sub(nMinus1, bigOne)
+		bitLen := nMinus1.BitLen()
+		if bitLen%8 == 0 {
+			// The number will need 0xff padding
+			length++
+		}
+		length += (bitLen + 7) / 8
+	} else if n.Sign() == 0 {
+		// A zero is the zero length string
+	} else {
+		bitLen := n.BitLen()
+		if bitLen%8 == 0 {
+			// The number will need 0x00 padding
+			length++
+		}
+		length += (bitLen + 7) / 8
+	}
+
+	return length
+}
+
+func marshalUint32(to []byte, n uint32) []byte {
+	binary.BigEndian.PutUint32(to, n)
+	return to[4:]
+}
+
+func marshalUint64(to []byte, n uint64) []byte {
+	binary.BigEndian.PutUint64(to, n)
+	return to[8:]
+}
+
+func marshalInt(to []byte, n *big.Int) []byte {
+	lengthBytes := to
+	to = to[4:]
+	length := 0
+
+	if n.Sign() < 0 {
+		// A negative number has to be converted to two's-complement
+		// form. So we'll subtract 1 and invert. If the
+		// most-significant-bit isn't set then we'll need to pad the
+		// beginning with 0xff in order to keep the number negative.
+		nMinus1 := new(big.Int).Neg(n)
+		nMinus1.Sub(nMinus1, bigOne)
+		bytes := nMinus1.Bytes()
+		for i := range bytes {
+			bytes[i] ^= 0xff
+		}
+		if len(bytes) == 0 || bytes[0]&0x80 == 0 {
+			to[0] = 0xff
+			to = to[1:]
+			length++
+		}
+		nBytes := copy(to, bytes)
+		to = to[nBytes:]
+		length += nBytes
+	} else if n.Sign() == 0 {
+		// A zero is the zero length string
+	} else {
+		bytes := n.Bytes()
+		if len(bytes) > 0 && bytes[0]&0x80 != 0 {
+			// We'll have to pad this with a 0x00 in order to
+			// stop it looking like a negative number.
+			to[0] = 0
+			to = to[1:]
+			length++
+		}
+		nBytes := copy(to, bytes)
+		to = to[nBytes:]
+		length += nBytes
+	}
+
+	lengthBytes[0] = byte(length >> 24)
+	lengthBytes[1] = byte(length >> 16)
+	lengthBytes[2] = byte(length >> 8)
+	lengthBytes[3] = byte(length)
+	return to
+}
+
+func writeInt(w io.Writer, n *big.Int) {
+	length := intLength(n)
+	buf := make([]byte, length)
+	marshalInt(buf, n)
+	w.Write(buf)
+}
+
+func writeString(w io.Writer, s []byte) {
+	var lengthBytes [4]byte
+	lengthBytes[0] = byte(len(s) >> 24)
+	lengthBytes[1] = byte(len(s) >> 16)
+	lengthBytes[2] = byte(len(s) >> 8)
+	lengthBytes[3] = byte(len(s))
+	w.Write(lengthBytes[:])
+	w.Write(s)
+}
+
+func stringLength(n int) int {
+	return 4 + n
+}
+
+func marshalString(to []byte, s []byte) []byte {
+	to[0] = byte(len(s) >> 24)
+	to[1] = byte(len(s) >> 16)
+	to[2] = byte(len(s) >> 8)
+	to[3] = byte(len(s))
+	to = to[4:]
+	copy(to, s)
+	return to[len(s):]
+}
+
+var bigIntType = reflect.TypeOf((*big.Int)(nil))
+
+// Decode a packet into its corresponding message.
+func decode(packet []byte) (interface{}, error) {
+	var msg interface{}
+	switch packet[0] {
+	case msgDisconnect:
+		msg = new(disconnectMsg)
+	case msgServiceRequest:
+		msg = new(serviceRequestMsg)
+	case msgServiceAccept:
+		msg = new(serviceAcceptMsg)
+	case msgKexInit:
+		msg = new(kexInitMsg)
+	case msgKexDHInit:
+		msg = new(kexDHInitMsg)
+	case msgKexDHReply:
+		msg = new(kexDHReplyMsg)
+	case msgUserAuthRequest:
+		msg = new(userAuthRequestMsg)
+	case msgUserAuthSuccess:
+		return new(userAuthSuccessMsg), nil
+	case msgUserAuthFailure:
+		msg = new(userAuthFailureMsg)
+	case msgUserAuthPubKeyOk:
+		msg = new(userAuthPubKeyOkMsg)
+	case msgGlobalRequest:
+		msg = new(globalRequestMsg)
+	case msgRequestSuccess:
+		msg = new(globalRequestSuccessMsg)
+	case msgRequestFailure:
+		msg = new(globalRequestFailureMsg)
+	case msgChannelOpen:
+		msg = new(channelOpenMsg)
+	case msgChannelData:
+		msg = new(channelDataMsg)
+	case msgChannelOpenConfirm:
+		msg = new(channelOpenConfirmMsg)
+	case msgChannelOpenFailure:
+		msg = new(channelOpenFailureMsg)
+	case msgChannelWindowAdjust:
+		msg = new(windowAdjustMsg)
+	case msgChannelEOF:
+		msg = new(channelEOFMsg)
+	case msgChannelClose:
+		msg = new(channelCloseMsg)
+	case msgChannelRequest:
+		msg = new(channelRequestMsg)
+	case msgChannelSuccess:
+		msg = new(channelRequestSuccessMsg)
+	case msgChannelFailure:
+		msg = new(channelRequestFailureMsg)
+	default:
+		return nil, unexpectedMessageError(0, packet[0])
+	}
+	if err := Unmarshal(packet, msg); err != nil {
+		return nil, err
+	}
+	return msg, nil
+}

vendor/golang.org/x/crypto/ssh/mux.go

@@ -0,0 +1,330 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"encoding/binary"
+	"fmt"
+	"io"
+	"log"
+	"sync"
+	"sync/atomic"
+)
+
+// debugMux, if set, causes messages in the connection protocol to be
+// logged.
+const debugMux = false
+
+// chanList is a thread safe channel list.
+type chanList struct {
+	// protects concurrent access to chans
+	sync.Mutex
+
+	// chans are indexed by the local id of the channel, which the
+	// other side should send in the PeersId field.
+	chans []*channel
+
+	// This is a debugging aid: it offsets all IDs by this
+	// amount. This helps distinguish otherwise identical
+	// server/client muxes
+	offset uint32
+}
+
+// Assigns a channel ID to the given channel.
+func (c *chanList) add(ch *channel) uint32 {
+	c.Lock()
+	defer c.Unlock()
+	for i := range c.chans {
+		if c.chans[i] == nil {
+			c.chans[i] = ch
+			return uint32(i) + c.offset
+		}
+	}
+	c.chans = append(c.chans, ch)
+	return uint32(len(c.chans)-1) + c.offset
+}
+
+// getChan returns the channel for the given ID.
+func (c *chanList) getChan(id uint32) *channel {
+	id -= c.offset
+
+	c.Lock()
+	defer c.Unlock()
+	if id < uint32(len(c.chans)) {
+		return c.chans[id]
+	}
+	return nil
+}
+
+func (c *chanList) remove(id uint32) {
+	id -= c.offset
+	c.Lock()
+	if id < uint32(len(c.chans)) {
+		c.chans[id] = nil
+	}
+	c.Unlock()
+}
+
+// dropAll forgets all channels it knows, returning them in a slice.
+func (c *chanList) dropAll() []*channel {
+	c.Lock()
+	defer c.Unlock()
+	var r []*channel
+
+	for _, ch := range c.chans {
+		if ch == nil {
+			continue
+		}
+		r = append(r, ch)
+	}
+	c.chans = nil
+	return r
+}
+
+// mux represents the state for the SSH connection protocol, which
+// multiplexes many channels onto a single packet transport.
+type mux struct {
+	conn     packetConn
+	chanList chanList
+
+	incomingChannels chan NewChannel
+
+	globalSentMu     sync.Mutex
+	globalResponses  chan interface{}
+	incomingRequests chan *Request
+
+	errCond *sync.Cond
+	err     error
+}
+
+// When debugging, each new chanList instantiation has a different
+// offset.
+var globalOff uint32
+
+func (m *mux) Wait() error {
+	m.errCond.L.Lock()
+	defer m.errCond.L.Unlock()
+	for m.err == nil {
+		m.errCond.Wait()
+	}
+	return m.err
+}
+
+// newMux returns a mux that runs over the given connection.
+func newMux(p packetConn) *mux {
+	m := &mux{
+		conn:             p,
+		incomingChannels: make(chan NewChannel, chanSize),
+		globalResponses:  make(chan interface{}, 1),
+		incomingRequests: make(chan *Request, chanSize),
+		errCond:          newCond(),
+	}
+	if debugMux {
+		m.chanList.offset = atomic.AddUint32(&globalOff, 1)
+	}
+
+	go m.loop()
+	return m
+}
+
+func (m *mux) sendMessage(msg interface{}) error {
+	p := Marshal(msg)
+	if debugMux {
+		log.Printf("send global(%d): %#v", m.chanList.offset, msg)
+	}
+	return m.conn.writePacket(p)
+}
+
+func (m *mux) SendRequest(name string, wantReply bool, payload []byte) (bool, []byte, error) {
+	if wantReply {
+		m.globalSentMu.Lock()
+		defer m.globalSentMu.Unlock()
+	}
+
+	if err := m.sendMessage(globalRequestMsg{
+		Type:      name,
+		WantReply: wantReply,
+		Data:      payload,
+	}); err != nil {
+		return false, nil, err
+	}
+
+	if !wantReply {
+		return false, nil, nil
+	}
+
+	msg, ok := <-m.globalResponses
+	if !ok {
+		return false, nil, io.EOF
+	}
+	switch msg := msg.(type) {
+	case *globalRequestFailureMsg:
+		return false, msg.Data, nil
+	case *globalRequestSuccessMsg:
+		return true, msg.Data, nil
+	default:
+		return false, nil, fmt.Errorf("ssh: unexpected response to request: %#v", msg)
+	}
+}
+
+// ackRequest must be called after processing a global request that
+// has WantReply set.
+func (m *mux) ackRequest(ok bool, data []byte) error {
+	if ok {
+		return m.sendMessage(globalRequestSuccessMsg{Data: data})
+	}
+	return m.sendMessage(globalRequestFailureMsg{Data: data})
+}
+
+func (m *mux) Close() error {
+	return m.conn.Close()
+}
+
+// loop runs the connection machine. It will process packets until an
+// error is encountered. To synchronize on loop exit, use mux.Wait.
+func (m *mux) loop() {
+	var err error
+	for err == nil {
+		err = m.onePacket()
+	}
+
+	for _, ch := range m.chanList.dropAll() {
+		ch.close()
+	}
+
+	close(m.incomingChannels)
+	close(m.incomingRequests)
+	close(m.globalResponses)
+
+	m.conn.Close()
+
+	m.errCond.L.Lock()
+	m.err = err
+	m.errCond.Broadcast()
+	m.errCond.L.Unlock()
+
+	if debugMux {
+		log.Println("loop exit", err)
+	}
+}
+
+// onePacket reads and processes one packet.
+func (m *mux) onePacket() error {
+	packet, err := m.conn.readPacket()
+	if err != nil {
+		return err
+	}
+
+	if debugMux {
+		if packet[0] == msgChannelData || packet[0] == msgChannelExtendedData {
+			log.Printf("decoding(%d): data packet - %d bytes", m.chanList.offset, len(packet))
+		} else {
+			p, _ := decode(packet)
+			log.Printf("decoding(%d): %d %#v - %d bytes", m.chanList.offset, packet[0], p, len(packet))
+		}
+	}
+
+	switch packet[0] {
+	case msgChannelOpen:
+		return m.handleChannelOpen(packet)
+	case msgGlobalRequest, msgRequestSuccess, msgRequestFailure:
+		return m.handleGlobalPacket(packet)
+	}
+
+	// assume a channel packet.
+	if len(packet) < 5 {
+		return parseError(packet[0])
+	}
+	id := binary.BigEndian.Uint32(packet[1:])
+	ch := m.chanList.getChan(id)
+	if ch == nil {
+		return fmt.Errorf("ssh: invalid channel %d", id)
+	}
+
+	return ch.handlePacket(packet)
+}
+
+func (m *mux) handleGlobalPacket(packet []byte) error {
+	msg, err := decode(packet)
+	if err != nil {
+		return err
+	}
+
+	switch msg := msg.(type) {
+	case *globalRequestMsg:
+		m.incomingRequests <- &Request{
+			Type:      msg.Type,
+			WantReply: msg.WantReply,
+			Payload:   msg.Data,
+			mux:       m,
+		}
+	case *globalRequestSuccessMsg, *globalRequestFailureMsg:
+		m.globalResponses <- msg
+	default:
+		panic(fmt.Sprintf("not a global message %#v", msg))
+	}
+
+	return nil
+}
+
+// handleChannelOpen schedules a channel to be Accept()ed.
+func (m *mux) handleChannelOpen(packet []byte) error {
+	var msg channelOpenMsg
+	if err := Unmarshal(packet, &msg); err != nil {
+		return err
+	}
+
+	if msg.MaxPacketSize < minPacketLength || msg.MaxPacketSize > 1<<31 {
+		failMsg := channelOpenFailureMsg{
+			PeersId:  msg.PeersId,
+			Reason:   ConnectionFailed,
+			Message:  "invalid request",
+			Language: "en_US.UTF-8",
+		}
+		return m.sendMessage(failMsg)
+	}
+
+	c := m.newChannel(msg.ChanType, channelInbound, msg.TypeSpecificData)
+	c.remoteId = msg.PeersId
+	c.maxRemotePayload = msg.MaxPacketSize
+	c.remoteWin.add(msg.PeersWindow)
+	m.incomingChannels <- c
+	return nil
+}
+
+func (m *mux) OpenChannel(chanType string, extra []byte) (Channel, <-chan *Request, error) {
+	ch, err := m.openChannel(chanType, extra)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return ch, ch.incomingRequests, nil
+}
+
+func (m *mux) openChannel(chanType string, extra []byte) (*channel, error) {
+	ch := m.newChannel(chanType, channelOutbound, extra)
+
+	ch.maxIncomingPayload = channelMaxPacket
+
+	open := channelOpenMsg{
+		ChanType:         chanType,
+		PeersWindow:      ch.myWindow,
+		MaxPacketSize:    ch.maxIncomingPayload,
+		TypeSpecificData: extra,
+		PeersId:          ch.localId,
+	}
+	if err := m.sendMessage(open); err != nil {
+		return nil, err
+	}
+
+	switch msg := (<-ch.msg).(type) {
+	case *channelOpenConfirmMsg:
+		return ch, nil
+	case *channelOpenFailureMsg:
+		return nil, &OpenChannelError{msg.Reason, msg.Message}
+	default:
+		return nil, fmt.Errorf("ssh: unexpected packet in response to channel open: %T", msg)
+	}
+}

vendor/golang.org/x/crypto/ssh/server.go

@@ -0,0 +1,580 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"strings"
+)
+
+// The Permissions type holds fine-grained permissions that are
+// specific to a user or a specific authentication method for a user.
+// The Permissions value for a successful authentication attempt is
+// available in ServerConn, so it can be used to pass information from
+// the user-authentication phase to the application layer.
+type Permissions struct {
+	// CriticalOptions indicate restrictions to the default
+	// permissions, and are typically used in conjunction with
+	// user certificates. The standard for SSH certificates
+	// defines "force-command" (only allow the given command to
+	// execute) and "source-address" (only allow connections from
+	// the given address). The SSH package currently only enforces
+	// the "source-address" critical option. It is up to server
+	// implementations to enforce other critical options, such as
+	// "force-command", by checking them after the SSH handshake
+	// is successful. In general, SSH servers should reject
+	// connections that specify critical options that are unknown
+	// or not supported.
+	CriticalOptions map[string]string
+
+	// Extensions are extra functionality that the server may
+	// offer on authenticated connections. Lack of support for an
+	// extension does not preclude authenticating a user. Common
+	// extensions are "permit-agent-forwarding",
+	// "permit-X11-forwarding". The Go SSH library currently does
+	// not act on any extension, and it is up to server
+	// implementations to honor them. Extensions can be used to
+	// pass data from the authentication callbacks to the server
+	// application layer.
+	Extensions map[string]string
+}
+
+// ServerConfig holds server specific configuration data.
+type ServerConfig struct {
+	// Config contains configuration shared between client and server.
+	Config
+
+	hostKeys []Signer
+
+	// NoClientAuth is true if clients are allowed to connect without
+	// authenticating.
+	NoClientAuth bool
+
+	// MaxAuthTries specifies the maximum number of authentication attempts
+	// permitted per connection. If set to a negative number, the number of
+	// attempts are unlimited. If set to zero, the number of attempts are limited
+	// to 6.
+	MaxAuthTries int
+
+	// PasswordCallback, if non-nil, is called when a user
+	// attempts to authenticate using a password.
+	PasswordCallback func(conn ConnMetadata, password []byte) (*Permissions, error)
+
+	// PublicKeyCallback, if non-nil, is called when a client
+	// offers a public key for authentication. It must return a nil error
+	// if the given public key can be used to authenticate the
+	// given user. For example, see CertChecker.Authenticate. A
+	// call to this function does not guarantee that the key
+	// offered is in fact used to authenticate. To record any data
+	// depending on the public key, store it inside a
+	// Permissions.Extensions entry.
+	PublicKeyCallback func(conn ConnMetadata, key PublicKey) (*Permissions, error)
+
+	// KeyboardInteractiveCallback, if non-nil, is called when
+	// keyboard-interactive authentication is selected (RFC
+	// 4256). The client object's Challenge function should be
+	// used to query the user. The callback may offer multiple
+	// Challenge rounds. To avoid information leaks, the client
+	// should be presented a challenge even if the user is
+	// unknown.
+	KeyboardInteractiveCallback func(conn ConnMetadata, client KeyboardInteractiveChallenge) (*Permissions, error)
+
+	// AuthLogCallback, if non-nil, is called to log all authentication
+	// attempts.
+	AuthLogCallback func(conn ConnMetadata, method string, err error)
+
+	// ServerVersion is the version identification string to announce in
+	// the public handshake.
+	// If empty, a reasonable default is used.
+	// Note that RFC 4253 section 4.2 requires that this string start with
+	// "SSH-2.0-".
+	ServerVersion string
+
+	// BannerCallback, if present, is called and the return string is sent to
+	// the client after key exchange completed but before authentication.
+	BannerCallback func(conn ConnMetadata) string
+}
+
+// AddHostKey adds a private key as a host key. If an existing host
+// key exists with the same algorithm, it is overwritten. Each server
+// config must have at least one host key.
+func (s *ServerConfig) AddHostKey(key Signer) {
+	for i, k := range s.hostKeys {
+		if k.PublicKey().Type() == key.PublicKey().Type() {
+			s.hostKeys[i] = key
+			return
+		}
+	}
+
+	s.hostKeys = append(s.hostKeys, key)
+}
+
+// cachedPubKey contains the results of querying whether a public key is
+// acceptable for a user.
+type cachedPubKey struct {
+	user       string
+	pubKeyData []byte
+	result     error
+	perms      *Permissions
+}
+
+const maxCachedPubKeys = 16
+
+// pubKeyCache caches tests for public keys.  Since SSH clients
+// will query whether a public key is acceptable before attempting to
+// authenticate with it, we end up with duplicate queries for public
+// key validity.  The cache only applies to a single ServerConn.
+type pubKeyCache struct {
+	keys []cachedPubKey
+}
+
+// get returns the result for a given user/algo/key tuple.
+func (c *pubKeyCache) get(user string, pubKeyData []byte) (cachedPubKey, bool) {
+	for _, k := range c.keys {
+		if k.user == user && bytes.Equal(k.pubKeyData, pubKeyData) {
+			return k, true
+		}
+	}
+	return cachedPubKey{}, false
+}
+
+// add adds the given tuple to the cache.
+func (c *pubKeyCache) add(candidate cachedPubKey) {
+	if len(c.keys) < maxCachedPubKeys {
+		c.keys = append(c.keys, candidate)
+	}
+}
+
+// ServerConn is an authenticated SSH connection, as seen from the
+// server
+type ServerConn struct {
+	Conn
+
+	// If the succeeding authentication callback returned a
+	// non-nil Permissions pointer, it is stored here.
+	Permissions *Permissions
+}
+
+// NewServerConn starts a new SSH server with c as the underlying
+// transport.  It starts with a handshake and, if the handshake is
+// unsuccessful, it closes the connection and returns an error.  The
+// Request and NewChannel channels must be serviced, or the connection
+// will hang.
+func NewServerConn(c net.Conn, config *ServerConfig) (*ServerConn, <-chan NewChannel, <-chan *Request, error) {
+	fullConf := *config
+	fullConf.SetDefaults()
+	if fullConf.MaxAuthTries == 0 {
+		fullConf.MaxAuthTries = 6
+	}
+
+	s := &connection{
+		sshConn: sshConn{conn: c},
+	}
+	perms, err := s.serverHandshake(&fullConf)
+	if err != nil {
+		c.Close()
+		return nil, nil, nil, err
+	}
+	return &ServerConn{s, perms}, s.mux.incomingChannels, s.mux.incomingRequests, nil
+}
+
+// signAndMarshal signs the data with the appropriate algorithm,
+// and serializes the result in SSH wire format.
+func signAndMarshal(k Signer, rand io.Reader, data []byte) ([]byte, error) {
+	sig, err := k.Sign(rand, data)
+	if err != nil {
+		return nil, err
+	}
+
+	return Marshal(sig), nil
+}
+
+// handshake performs key exchange and user authentication.
+func (s *connection) serverHandshake(config *ServerConfig) (*Permissions, error) {
+	if len(config.hostKeys) == 0 {
+		return nil, errors.New("ssh: server has no host keys")
+	}
+
+	if !config.NoClientAuth && config.PasswordCallback == nil && config.PublicKeyCallback == nil && config.KeyboardInteractiveCallback == nil {
+		return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")
+	}
+
+	if config.ServerVersion != "" {
+		s.serverVersion = []byte(config.ServerVersion)
+	} else {
+		s.serverVersion = []byte(packageVersion)
+	}
+	var err error
+	s.clientVersion, err = exchangeVersions(s.sshConn.conn, s.serverVersion)
+	if err != nil {
+		return nil, err
+	}
+
+	tr := newTransport(s.sshConn.conn, config.Rand, false /* not client */)
+	s.transport = newServerTransport(tr, s.clientVersion, s.serverVersion, config)
+
+	if err := s.transport.waitSession(); err != nil {
+		return nil, err
+	}
+
+	// We just did the key change, so the session ID is established.
+	s.sessionID = s.transport.getSessionID()
+
+	var packet []byte
+	if packet, err = s.transport.readPacket(); err != nil {
+		return nil, err
+	}
+
+	var serviceRequest serviceRequestMsg
+	if err = Unmarshal(packet, &serviceRequest); err != nil {
+		return nil, err
+	}
+	if serviceRequest.Service != serviceUserAuth {
+		return nil, errors.New("ssh: requested service '" + serviceRequest.Service + "' before authenticating")
+	}
+	serviceAccept := serviceAcceptMsg{
+		Service: serviceUserAuth,
+	}
+	if err := s.transport.writePacket(Marshal(&serviceAccept)); err != nil {
+		return nil, err
+	}
+
+	perms, err := s.serverAuthenticate(config)
+	if err != nil {
+		return nil, err
+	}
+	s.mux = newMux(s.transport)
+	return perms, err
+}
+
+func isAcceptableAlgo(algo string) bool {
+	switch algo {
+	case KeyAlgoRSA, KeyAlgoDSA, KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521, KeyAlgoED25519,
+		CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01:
+		return true
+	}
+	return false
+}
+
+func checkSourceAddress(addr net.Addr, sourceAddrs string) error {
+	if addr == nil {
+		return errors.New("ssh: no address known for client, but source-address match required")
+	}
+
+	tcpAddr, ok := addr.(*net.TCPAddr)
+	if !ok {
+		return fmt.Errorf("ssh: remote address %v is not an TCP address when checking source-address match", addr)
+	}
+
+	for _, sourceAddr := range strings.Split(sourceAddrs, ",") {
+		if allowedIP := net.ParseIP(sourceAddr); allowedIP != nil {
+			if allowedIP.Equal(tcpAddr.IP) {
+				return nil
+			}
+		} else {
+			_, ipNet, err := net.ParseCIDR(sourceAddr)
+			if err != nil {
+				return fmt.Errorf("ssh: error parsing source-address restriction %q: %v", sourceAddr, err)
+			}
+
+			if ipNet.Contains(tcpAddr.IP) {
+				return nil
+			}
+		}
+	}
+
+	return fmt.Errorf("ssh: remote address %v is not allowed because of source-address restriction", addr)
+}
+
+// ServerAuthError implements the error interface. It appends any authentication
+// errors that may occur, and is returned if all of the authentication methods
+// provided by the user failed to authenticate.
+type ServerAuthError struct {
+	// Errors contains authentication errors returned by the authentication
+	// callback methods.
+	Errors []error
+}
+
+func (l ServerAuthError) Error() string {
+	var errs []string
+	for _, err := range l.Errors {
+		errs = append(errs, err.Error())
+	}
+	return "[" + strings.Join(errs, ", ") + "]"
+}
+
+func (s *connection) serverAuthenticate(config *ServerConfig) (*Permissions, error) {
+	sessionID := s.transport.getSessionID()
+	var cache pubKeyCache
+	var perms *Permissions
+
+	authFailures := 0
+	var authErrs []error
+
+userAuthLoop:
+	for {
+		if authFailures >= config.MaxAuthTries && config.MaxAuthTries > 0 {
+			discMsg := &disconnectMsg{
+				Reason:  2,
+				Message: "too many authentication failures",
+			}
+
+			if err := s.transport.writePacket(Marshal(discMsg)); err != nil {
+				return nil, err
+			}
+
+			return nil, discMsg
+		}
+
+		var userAuthReq userAuthRequestMsg
+		if packet, err := s.transport.readPacket(); err != nil {
+			if err == io.EOF {
+				return nil, &ServerAuthError{Errors: authErrs}
+			}
+			return nil, err
+		} else if err = Unmarshal(packet, &userAuthReq); err != nil {
+			return nil, err
+		}
+
+		if userAuthReq.Service != serviceSSH {
+			return nil, errors.New("ssh: client attempted to negotiate for unknown service: " + userAuthReq.Service)
+		}
+
+		s.user = userAuthReq.User
+
+		if authFailures == 0 && config.BannerCallback != nil {
+			msg := config.BannerCallback(s)
+			if msg != "" {
+				bannerMsg := &userAuthBannerMsg{
+					Message: msg,
+				}
+				if err := s.transport.writePacket(Marshal(bannerMsg)); err != nil {
+					return nil, err
+				}
+			}
+		}
+
+		perms = nil
+		authErr := errors.New("no auth passed yet")
+
+		switch userAuthReq.Method {
+		case "none":
+			if config.NoClientAuth {
+				authErr = nil
+			}
+
+			// allow initial attempt of 'none' without penalty
+			if authFailures == 0 {
+				authFailures--
+			}
+		case "password":
+			if config.PasswordCallback == nil {
+				authErr = errors.New("ssh: password auth not configured")
+				break
+			}
+			payload := userAuthReq.Payload
+			if len(payload) < 1 || payload[0] != 0 {
+				return nil, parseError(msgUserAuthRequest)
+			}
+			payload = payload[1:]
+			password, payload, ok := parseString(payload)
+			if !ok || len(payload) > 0 {
+				return nil, parseError(msgUserAuthRequest)
+			}
+
+			perms, authErr = config.PasswordCallback(s, password)
+		case "keyboard-interactive":
+			if config.KeyboardInteractiveCallback == nil {
+				authErr = errors.New("ssh: keyboard-interactive auth not configubred")
+				break
+			}
+
+			prompter := &sshClientKeyboardInteractive{s}
+			perms, authErr = config.KeyboardInteractiveCallback(s, prompter.Challenge)
+		case "publickey":
+			if config.PublicKeyCallback == nil {
+				authErr = errors.New("ssh: publickey auth not configured")
+				break
+			}
+			payload := userAuthReq.Payload
+			if len(payload) < 1 {
+				return nil, parseError(msgUserAuthRequest)
+			}
+			isQuery := payload[0] == 0
+			payload = payload[1:]
+			algoBytes, payload, ok := parseString(payload)
+			if !ok {
+				return nil, parseError(msgUserAuthRequest)
+			}
+			algo := string(algoBytes)
+			if !isAcceptableAlgo(algo) {
+				authErr = fmt.Errorf("ssh: algorithm %q not accepted", algo)
+				break
+			}
+
+			pubKeyData, payload, ok := parseString(payload)
+			if !ok {
+				return nil, parseError(msgUserAuthRequest)
+			}
+
+			pubKey, err := ParsePublicKey(pubKeyData)
+			if err != nil {
+				return nil, err
+			}
+
+			candidate, ok := cache.get(s.user, pubKeyData)
+			if !ok {
+				candidate.user = s.user
+				candidate.pubKeyData = pubKeyData
+				candidate.perms, candidate.result = config.PublicKeyCallback(s, pubKey)
+				if candidate.result == nil && candidate.perms != nil && candidate.perms.CriticalOptions != nil && candidate.perms.CriticalOptions[sourceAddressCriticalOption] != "" {
+					candidate.result = checkSourceAddress(
+						s.RemoteAddr(),
+						candidate.perms.CriticalOptions[sourceAddressCriticalOption])
+				}
+				cache.add(candidate)
+			}
+
+			if isQuery {
+				// The client can query if the given public key
+				// would be okay.
+
+				if len(payload) > 0 {
+					return nil, parseError(msgUserAuthRequest)
+				}
+
+				if candidate.result == nil {
+					okMsg := userAuthPubKeyOkMsg{
+						Algo:   algo,
+						PubKey: pubKeyData,
+					}
+					if err = s.transport.writePacket(Marshal(&okMsg)); err != nil {
+						return nil, err
+					}
+					continue userAuthLoop
+				}
+				authErr = candidate.result
+			} else {
+				sig, payload, ok := parseSignature(payload)
+				if !ok || len(payload) > 0 {
+					return nil, parseError(msgUserAuthRequest)
+				}
+				// Ensure the public key algo and signature algo
+				// are supported.  Compare the private key
+				// algorithm name that corresponds to algo with
+				// sig.Format.  This is usually the same, but
+				// for certs, the names differ.
+				if !isAcceptableAlgo(sig.Format) {
+					break
+				}
+				signedData := buildDataSignedForAuth(sessionID, userAuthReq, algoBytes, pubKeyData)
+
+				if err := pubKey.Verify(signedData, sig); err != nil {
+					return nil, err
+				}
+
+				authErr = candidate.result
+				perms = candidate.perms
+			}
+		default:
+			authErr = fmt.Errorf("ssh: unknown method %q", userAuthReq.Method)
+		}
+
+		authErrs = append(authErrs, authErr)
+
+		if config.AuthLogCallback != nil {
+			config.AuthLogCallback(s, userAuthReq.Method, authErr)
+		}
+
+		if authErr == nil {
+			break userAuthLoop
+		}
+
+		authFailures++
+
+		var failureMsg userAuthFailureMsg
+		if config.PasswordCallback != nil {
+			failureMsg.Methods = append(failureMsg.Methods, "password")
+		}
+		if config.PublicKeyCallback != nil {
+			failureMsg.Methods = append(failureMsg.Methods, "publickey")
+		}
+		if config.KeyboardInteractiveCallback != nil {
+			failureMsg.Methods = append(failureMsg.Methods, "keyboard-interactive")
+		}
+
+		if len(failureMsg.Methods) == 0 {
+			return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")
+		}
+
+		if err := s.transport.writePacket(Marshal(&failureMsg)); err != nil {
+			return nil, err
+		}
+	}
+
+	if err := s.transport.writePacket([]byte{msgUserAuthSuccess}); err != nil {
+		return nil, err
+	}
+	return perms, nil
+}
+
+// sshClientKeyboardInteractive implements a ClientKeyboardInteractive by
+// asking the client on the other side of a ServerConn.
+type sshClientKeyboardInteractive struct {
+	*connection
+}
+
+func (c *sshClientKeyboardInteractive) Challenge(user, instruction string, questions []string, echos []bool) (answers []string, err error) {
+	if len(questions) != len(echos) {
+		return nil, errors.New("ssh: echos and questions must have equal length")
+	}
+
+	var prompts []byte
+	for i := range questions {
+		prompts = appendString(prompts, questions[i])
+		prompts = appendBool(prompts, echos[i])
+	}
+
+	if err := c.transport.writePacket(Marshal(&userAuthInfoRequestMsg{
+		Instruction: instruction,
+		NumPrompts:  uint32(len(questions)),
+		Prompts:     prompts,
+	})); err != nil {
+		return nil, err
+	}
+
+	packet, err := c.transport.readPacket()
+	if err != nil {
+		return nil, err
+	}
+	if packet[0] != msgUserAuthInfoResponse {
+		return nil, unexpectedMessageError(msgUserAuthInfoResponse, packet[0])
+	}
+	packet = packet[1:]
+
+	n, packet, ok := parseUint32(packet)
+	if !ok || int(n) != len(questions) {
+		return nil, parseError(msgUserAuthInfoResponse)
+	}
+
+	for i := uint32(0); i < n; i++ {
+		ans, rest, ok := parseString(packet)
+		if !ok {
+			return nil, parseError(msgUserAuthInfoResponse)
+		}
+
+		answers = append(answers, string(ans))
+		packet = rest
+	}
+	if len(packet) != 0 {
+		return nil, errors.New("ssh: junk at end of message")
+	}
+
+	return answers, nil
+}

vendor/golang.org/x/crypto/ssh/session.go

@@ -0,0 +1,647 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+// Session implements an interactive session described in
+// "RFC 4254, section 6".
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"sync"
+)
+
+type Signal string
+
+// POSIX signals as listed in RFC 4254 Section 6.10.
+const (
+	SIGABRT Signal = "ABRT"
+	SIGALRM Signal = "ALRM"
+	SIGFPE  Signal = "FPE"
+	SIGHUP  Signal = "HUP"
+	SIGILL  Signal = "ILL"
+	SIGINT  Signal = "INT"
+	SIGKILL Signal = "KILL"
+	SIGPIPE Signal = "PIPE"
+	SIGQUIT Signal = "QUIT"
+	SIGSEGV Signal = "SEGV"
+	SIGTERM Signal = "TERM"
+	SIGUSR1 Signal = "USR1"
+	SIGUSR2 Signal = "USR2"
+)
+
+var signals = map[Signal]int{
+	SIGABRT: 6,
+	SIGALRM: 14,
+	SIGFPE:  8,
+	SIGHUP:  1,
+	SIGILL:  4,
+	SIGINT:  2,
+	SIGKILL: 9,
+	SIGPIPE: 13,
+	SIGQUIT: 3,
+	SIGSEGV: 11,
+	SIGTERM: 15,
+}
+
+type TerminalModes map[uint8]uint32
+
+// POSIX terminal mode flags as listed in RFC 4254 Section 8.
+const (
+	tty_OP_END    = 0
+	VINTR         = 1
+	VQUIT         = 2
+	VERASE        = 3
+	VKILL         = 4
+	VEOF          = 5
+	VEOL          = 6
+	VEOL2         = 7
+	VSTART        = 8
+	VSTOP         = 9
+	VSUSP         = 10
+	VDSUSP        = 11
+	VREPRINT      = 12
+	VWERASE       = 13
+	VLNEXT        = 14
+	VFLUSH        = 15
+	VSWTCH        = 16
+	VSTATUS       = 17
+	VDISCARD      = 18
+	IGNPAR        = 30
+	PARMRK        = 31
+	INPCK         = 32
+	ISTRIP        = 33
+	INLCR         = 34
+	IGNCR         = 35
+	ICRNL         = 36
+	IUCLC         = 37
+	IXON          = 38
+	IXANY         = 39
+	IXOFF         = 40
+	IMAXBEL       = 41
+	ISIG          = 50
+	ICANON        = 51
+	XCASE         = 52
+	ECHO          = 53
+	ECHOE         = 54
+	ECHOK         = 55
+	ECHONL        = 56
+	NOFLSH        = 57
+	TOSTOP        = 58
+	IEXTEN        = 59
+	ECHOCTL       = 60
+	ECHOKE        = 61
+	PENDIN        = 62
+	OPOST         = 70
+	OLCUC         = 71
+	ONLCR         = 72
+	OCRNL         = 73
+	ONOCR         = 74
+	ONLRET        = 75
+	CS7           = 90
+	CS8           = 91
+	PARENB        = 92
+	PARODD        = 93
+	TTY_OP_ISPEED = 128
+	TTY_OP_OSPEED = 129
+)
+
+// A Session represents a connection to a remote command or shell.
+type Session struct {
+	// Stdin specifies the remote process's standard input.
+	// If Stdin is nil, the remote process reads from an empty
+	// bytes.Buffer.
+	Stdin io.Reader
+
+	// Stdout and Stderr specify the remote process's standard
+	// output and error.
+	//
+	// If either is nil, Run connects the corresponding file
+	// descriptor to an instance of ioutil.Discard. There is a
+	// fixed amount of buffering that is shared for the two streams.
+	// If either blocks it may eventually cause the remote
+	// command to block.
+	Stdout io.Writer
+	Stderr io.Writer
+
+	ch        Channel // the channel backing this session
+	started   bool    // true once Start, Run or Shell is invoked.
+	copyFuncs []func() error
+	errors    chan error // one send per copyFunc
+
+	// true if pipe method is active
+	stdinpipe, stdoutpipe, stderrpipe bool
+
+	// stdinPipeWriter is non-nil if StdinPipe has not been called
+	// and Stdin was specified by the user; it is the write end of
+	// a pipe connecting Session.Stdin to the stdin channel.
+	stdinPipeWriter io.WriteCloser
+
+	exitStatus chan error
+}
+
+// SendRequest sends an out-of-band channel request on the SSH channel
+// underlying the session.
+func (s *Session) SendRequest(name string, wantReply bool, payload []byte) (bool, error) {
+	return s.ch.SendRequest(name, wantReply, payload)
+}
+
+func (s *Session) Close() error {
+	return s.ch.Close()
+}
+
+// RFC 4254 Section 6.4.
+type setenvRequest struct {
+	Name  string
+	Value string
+}
+
+// Setenv sets an environment variable that will be applied to any
+// command executed by Shell or Run.
+func (s *Session) Setenv(name, value string) error {
+	msg := setenvRequest{
+		Name:  name,
+		Value: value,
+	}
+	ok, err := s.ch.SendRequest("env", true, Marshal(&msg))
+	if err == nil && !ok {
+		err = errors.New("ssh: setenv failed")
+	}
+	return err
+}
+
+// RFC 4254 Section 6.2.
+type ptyRequestMsg struct {
+	Term     string
+	Columns  uint32
+	Rows     uint32
+	Width    uint32
+	Height   uint32
+	Modelist string
+}
+
+// RequestPty requests the association of a pty with the session on the remote host.
+func (s *Session) RequestPty(term string, h, w int, termmodes TerminalModes) error {
+	var tm []byte
+	for k, v := range termmodes {
+		kv := struct {
+			Key byte
+			Val uint32
+		}{k, v}
+
+		tm = append(tm, Marshal(&kv)...)
+	}
+	tm = append(tm, tty_OP_END)
+	req := ptyRequestMsg{
+		Term:     term,
+		Columns:  uint32(w),
+		Rows:     uint32(h),
+		Width:    uint32(w * 8),
+		Height:   uint32(h * 8),
+		Modelist: string(tm),
+	}
+	ok, err := s.ch.SendRequest("pty-req", true, Marshal(&req))
+	if err == nil && !ok {
+		err = errors.New("ssh: pty-req failed")
+	}
+	return err
+}
+
+// RFC 4254 Section 6.5.
+type subsystemRequestMsg struct {
+	Subsystem string
+}
+
+// RequestSubsystem requests the association of a subsystem with the session on the remote host.
+// A subsystem is a predefined command that runs in the background when the ssh session is initiated
+func (s *Session) RequestSubsystem(subsystem string) error {
+	msg := subsystemRequestMsg{
+		Subsystem: subsystem,
+	}
+	ok, err := s.ch.SendRequest("subsystem", true, Marshal(&msg))
+	if err == nil && !ok {
+		err = errors.New("ssh: subsystem request failed")
+	}
+	return err
+}
+
+// RFC 4254 Section 6.7.
+type ptyWindowChangeMsg struct {
+	Columns uint32
+	Rows    uint32
+	Width   uint32
+	Height  uint32
+}
+
+// WindowChange informs the remote host about a terminal window dimension change to h rows and w columns.
+func (s *Session) WindowChange(h, w int) error {
+	req := ptyWindowChangeMsg{
+		Columns: uint32(w),
+		Rows:    uint32(h),
+		Width:   uint32(w * 8),
+		Height:  uint32(h * 8),
+	}
+	_, err := s.ch.SendRequest("window-change", false, Marshal(&req))
+	return err
+}
+
+// RFC 4254 Section 6.9.
+type signalMsg struct {
+	Signal string
+}
+
+// Signal sends the given signal to the remote process.
+// sig is one of the SIG* constants.
+func (s *Session) Signal(sig Signal) error {
+	msg := signalMsg{
+		Signal: string(sig),
+	}
+
+	_, err := s.ch.SendRequest("signal", false, Marshal(&msg))
+	return err
+}
+
+// RFC 4254 Section 6.5.
+type execMsg struct {
+	Command string
+}
+
+// Start runs cmd on the remote host. Typically, the remote
+// server passes cmd to the shell for interpretation.
+// A Session only accepts one call to Run, Start or Shell.
+func (s *Session) Start(cmd string) error {
+	if s.started {
+		return errors.New("ssh: session already started")
+	}
+	req := execMsg{
+		Command: cmd,
+	}
+
+	ok, err := s.ch.SendRequest("exec", true, Marshal(&req))
+	if err == nil && !ok {
+		err = fmt.Errorf("ssh: command %v failed", cmd)
+	}
+	if err != nil {
+		return err
+	}
+	return s.start()
+}
+
+// Run runs cmd on the remote host. Typically, the remote
+// server passes cmd to the shell for interpretation.
+// A Session only accepts one call to Run, Start, Shell, Output,
+// or CombinedOutput.
+//
+// The returned error is nil if the command runs, has no problems
+// copying stdin, stdout, and stderr, and exits with a zero exit
+// status.
+//
+// If the remote server does not send an exit status, an error of type
+// *ExitMissingError is returned. If the command completes
+// unsuccessfully or is interrupted by a signal, the error is of type
+// *ExitError. Other error types may be returned for I/O problems.
+func (s *Session) Run(cmd string) error {
+	err := s.Start(cmd)
+	if err != nil {
+		return err
+	}
+	return s.Wait()
+}
+
+// Output runs cmd on the remote host and returns its standard output.
+func (s *Session) Output(cmd string) ([]byte, error) {
+	if s.Stdout != nil {
+		return nil, errors.New("ssh: Stdout already set")
+	}
+	var b bytes.Buffer
+	s.Stdout = &b
+	err := s.Run(cmd)
+	return b.Bytes(), err
+}
+
+type singleWriter struct {
+	b  bytes.Buffer
+	mu sync.Mutex
+}
+
+func (w *singleWriter) Write(p []byte) (int, error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	return w.b.Write(p)
+}
+
+// CombinedOutput runs cmd on the remote host and returns its combined
+// standard output and standard error.
+func (s *Session) CombinedOutput(cmd string) ([]byte, error) {
+	if s.Stdout != nil {
+		return nil, errors.New("ssh: Stdout already set")
+	}
+	if s.Stderr != nil {
+		return nil, errors.New("ssh: Stderr already set")
+	}
+	var b singleWriter
+	s.Stdout = &b
+	s.Stderr = &b
+	err := s.Run(cmd)
+	return b.b.Bytes(), err
+}
+
+// Shell starts a login shell on the remote host. A Session only
+// accepts one call to Run, Start, Shell, Output, or CombinedOutput.
+func (s *Session) Shell() error {
+	if s.started {
+		return errors.New("ssh: session already started")
+	}
+
+	ok, err := s.ch.SendRequest("shell", true, nil)
+	if err == nil && !ok {
+		return errors.New("ssh: could not start shell")
+	}
+	if err != nil {
+		return err
+	}
+	return s.start()
+}
+
+func (s *Session) start() error {
+	s.started = true
+
+	type F func(*Session)
+	for _, setupFd := range []F{(*Session).stdin, (*Session).stdout, (*Session).stderr} {
+		setupFd(s)
+	}
+
+	s.errors = make(chan error, len(s.copyFuncs))
+	for _, fn := range s.copyFuncs {
+		go func(fn func() error) {
+			s.errors <- fn()
+		}(fn)
+	}
+	return nil
+}
+
+// Wait waits for the remote command to exit.
+//
+// The returned error is nil if the command runs, has no problems
+// copying stdin, stdout, and stderr, and exits with a zero exit
+// status.
+//
+// If the remote server does not send an exit status, an error of type
+// *ExitMissingError is returned. If the command completes
+// unsuccessfully or is interrupted by a signal, the error is of type
+// *ExitError. Other error types may be returned for I/O problems.
+func (s *Session) Wait() error {
+	if !s.started {
+		return errors.New("ssh: session not started")
+	}
+	waitErr := <-s.exitStatus
+
+	if s.stdinPipeWriter != nil {
+		s.stdinPipeWriter.Close()
+	}
+	var copyError error
+	for _ = range s.copyFuncs {
+		if err := <-s.errors; err != nil && copyError == nil {
+			copyError = err
+		}
+	}
+	if waitErr != nil {
+		return waitErr
+	}
+	return copyError
+}
+
+func (s *Session) wait(reqs <-chan *Request) error {
+	wm := Waitmsg{status: -1}
+	// Wait for msg channel to be closed before returning.
+	for msg := range reqs {
+		switch msg.Type {
+		case "exit-status":
+			wm.status = int(binary.BigEndian.Uint32(msg.Payload))
+		case "exit-signal":
+			var sigval struct {
+				Signal     string
+				CoreDumped bool
+				Error      string
+				Lang       string
+			}
+			if err := Unmarshal(msg.Payload, &sigval); err != nil {
+				return err
+			}
+
+			// Must sanitize strings?
+			wm.signal = sigval.Signal
+			wm.msg = sigval.Error
+			wm.lang = sigval.Lang
+		default:
+			// This handles keepalives and matches
+			// OpenSSH's behaviour.
+			if msg.WantReply {
+				msg.Reply(false, nil)
+			}
+		}
+	}
+	if wm.status == 0 {
+		return nil
+	}
+	if wm.status == -1 {
+		// exit-status was never sent from server
+		if wm.signal == "" {
+			// signal was not sent either.  RFC 4254
+			// section 6.10 recommends against this
+			// behavior, but it is allowed, so we let
+			// clients handle it.
+			return &ExitMissingError{}
+		}
+		wm.status = 128
+		if _, ok := signals[Signal(wm.signal)]; ok {
+			wm.status += signals[Signal(wm.signal)]
+		}
+	}
+
+	return &ExitError{wm}
+}
+
+// ExitMissingError is returned if a session is torn down cleanly, but
+// the server sends no confirmation of the exit status.
+type ExitMissingError struct{}
+
+func (e *ExitMissingError) Error() string {
+	return "wait: remote command exited without exit status or exit signal"
+}
+
+func (s *Session) stdin() {
+	if s.stdinpipe {
+		return
+	}
+	var stdin io.Reader
+	if s.Stdin == nil {
+		stdin = new(bytes.Buffer)
+	} else {
+		r, w := io.Pipe()
+		go func() {
+			_, err := io.Copy(w, s.Stdin)
+			w.CloseWithError(err)
+		}()
+		stdin, s.stdinPipeWriter = r, w
+	}
+	s.copyFuncs = append(s.copyFuncs, func() error {
+		_, err := io.Copy(s.ch, stdin)
+		if err1 := s.ch.CloseWrite(); err == nil && err1 != io.EOF {
+			err = err1
+		}
+		return err
+	})
+}
+
+func (s *Session) stdout() {
+	if s.stdoutpipe {
+		return
+	}
+	if s.Stdout == nil {
+		s.Stdout = ioutil.Discard
+	}
+	s.copyFuncs = append(s.copyFuncs, func() error {
+		_, err := io.Copy(s.Stdout, s.ch)
+		return err
+	})
+}
+
+func (s *Session) stderr() {
+	if s.stderrpipe {
+		return
+	}
+	if s.Stderr == nil {
+		s.Stderr = ioutil.Discard
+	}
+	s.copyFuncs = append(s.copyFuncs, func() error {
+		_, err := io.Copy(s.Stderr, s.ch.Stderr())
+		return err
+	})
+}
+
+// sessionStdin reroutes Close to CloseWrite.
+type sessionStdin struct {
+	io.Writer
+	ch Channel
+}
+
+func (s *sessionStdin) Close() error {
+	return s.ch.CloseWrite()
+}
+
+// StdinPipe returns a pipe that will be connected to the
+// remote command's standard input when the command starts.
+func (s *Session) StdinPipe() (io.WriteCloser, error) {
+	if s.Stdin != nil {
+		return nil, errors.New("ssh: Stdin already set")
+	}
+	if s.started {
+		return nil, errors.New("ssh: StdinPipe after process started")
+	}
+	s.stdinpipe = true
+	return &sessionStdin{s.ch, s.ch}, nil
+}
+
+// StdoutPipe returns a pipe that will be connected to the
+// remote command's standard output when the command starts.
+// There is a fixed amount of buffering that is shared between
+// stdout and stderr streams. If the StdoutPipe reader is
+// not serviced fast enough it may eventually cause the
+// remote command to block.
+func (s *Session) StdoutPipe() (io.Reader, error) {
+	if s.Stdout != nil {
+		return nil, errors.New("ssh: Stdout already set")
+	}
+	if s.started {
+		return nil, errors.New("ssh: StdoutPipe after process started")
+	}
+	s.stdoutpipe = true
+	return s.ch, nil
+}
+
+// StderrPipe returns a pipe that will be connected to the
+// remote command's standard error when the command starts.
+// There is a fixed amount of buffering that is shared between
+// stdout and stderr streams. If the StderrPipe reader is
+// not serviced fast enough it may eventually cause the
+// remote command to block.
+func (s *Session) StderrPipe() (io.Reader, error) {
+	if s.Stderr != nil {
+		return nil, errors.New("ssh: Stderr already set")
+	}
+	if s.started {
+		return nil, errors.New("ssh: StderrPipe after process started")
+	}
+	s.stderrpipe = true
+	return s.ch.Stderr(), nil
+}
+
+// newSession returns a new interactive session on the remote host.
+func newSession(ch Channel, reqs <-chan *Request) (*Session, error) {
+	s := &Session{
+		ch: ch,
+	}
+	s.exitStatus = make(chan error, 1)
+	go func() {
+		s.exitStatus <- s.wait(reqs)
+	}()
+
+	return s, nil
+}
+
+// An ExitError reports unsuccessful completion of a remote command.
+type ExitError struct {
+	Waitmsg
+}
+
+func (e *ExitError) Error() string {
+	return e.Waitmsg.String()
+}
+
+// Waitmsg stores the information about an exited remote command
+// as reported by Wait.
+type Waitmsg struct {
+	status int
+	signal string
+	msg    string
+	lang   string
+}
+
+// ExitStatus returns the exit status of the remote command.
+func (w Waitmsg) ExitStatus() int {
+	return w.status
+}
+
+// Signal returns the exit signal of the remote command if
+// it was terminated violently.
+func (w Waitmsg) Signal() string {
+	return w.signal
+}
+
+// Msg returns the exit message given by the remote command
+func (w Waitmsg) Msg() string {
+	return w.msg
+}
+
+// Lang returns the language tag. See RFC 3066
+func (w Waitmsg) Lang() string {
+	return w.lang
+}
+
+func (w Waitmsg) String() string {
+	str := fmt.Sprintf("Process exited with status %v", w.status)
+	if w.signal != "" {
+		str += fmt.Sprintf(" from signal %v", w.signal)
+	}
+	if w.msg != "" {
+		str += fmt.Sprintf(". Reason was: %v", w.msg)
+	}
+	return str
+}

vendor/golang.org/x/crypto/ssh/streamlocal.go

@@ -0,0 +1,115 @@
+package ssh
+
+import (
+	"errors"
+	"io"
+	"net"
+)
+
+// streamLocalChannelOpenDirectMsg is a struct used for SSH_MSG_CHANNEL_OPEN message
+// with "direct-streamlocal@openssh.com" string.
+//
+// See openssh-portable/PROTOCOL, section 2.4. connection: Unix domain socket forwarding
+// https://github.com/openssh/openssh-portable/blob/master/PROTOCOL#L235
+type streamLocalChannelOpenDirectMsg struct {
+	socketPath string
+	reserved0  string
+	reserved1  uint32
+}
+
+// forwardedStreamLocalPayload is a struct used for SSH_MSG_CHANNEL_OPEN message
+// with "forwarded-streamlocal@openssh.com" string.
+type forwardedStreamLocalPayload struct {
+	SocketPath string
+	Reserved0  string
+}
+
+// streamLocalChannelForwardMsg is a struct used for SSH2_MSG_GLOBAL_REQUEST message
+// with "streamlocal-forward@openssh.com"/"cancel-streamlocal-forward@openssh.com" string.
+type streamLocalChannelForwardMsg struct {
+	socketPath string
+}
+
+// ListenUnix is similar to ListenTCP but uses a Unix domain socket.
+func (c *Client) ListenUnix(socketPath string) (net.Listener, error) {
+	m := streamLocalChannelForwardMsg{
+		socketPath,
+	}
+	// send message
+	ok, _, err := c.SendRequest("streamlocal-forward@openssh.com", true, Marshal(&m))
+	if err != nil {
+		return nil, err
+	}
+	if !ok {
+		return nil, errors.New("ssh: streamlocal-forward@openssh.com request denied by peer")
+	}
+	ch := c.forwards.add(&net.UnixAddr{Name: socketPath, Net: "unix"})
+
+	return &unixListener{socketPath, c, ch}, nil
+}
+
+func (c *Client) dialStreamLocal(socketPath string) (Channel, error) {
+	msg := streamLocalChannelOpenDirectMsg{
+		socketPath: socketPath,
+	}
+	ch, in, err := c.OpenChannel("direct-streamlocal@openssh.com", Marshal(&msg))
+	if err != nil {
+		return nil, err
+	}
+	go DiscardRequests(in)
+	return ch, err
+}
+
+type unixListener struct {
+	socketPath string
+
+	conn *Client
+	in   <-chan forward
+}
+
+// Accept waits for and returns the next connection to the listener.
+func (l *unixListener) Accept() (net.Conn, error) {
+	s, ok := <-l.in
+	if !ok {
+		return nil, io.EOF
+	}
+	ch, incoming, err := s.newCh.Accept()
+	if err != nil {
+		return nil, err
+	}
+	go DiscardRequests(incoming)
+
+	return &chanConn{
+		Channel: ch,
+		laddr: &net.UnixAddr{
+			Name: l.socketPath,
+			Net:  "unix",
+		},
+		raddr: &net.UnixAddr{
+			Name: "@",
+			Net:  "unix",
+		},
+	}, nil
+}
+
+// Close closes the listener.
+func (l *unixListener) Close() error {
+	// this also closes the listener.
+	l.conn.forwards.remove(&net.UnixAddr{Name: l.socketPath, Net: "unix"})
+	m := streamLocalChannelForwardMsg{
+		l.socketPath,
+	}
+	ok, _, err := l.conn.SendRequest("cancel-streamlocal-forward@openssh.com", true, Marshal(&m))
+	if err == nil && !ok {
+		err = errors.New("ssh: cancel-streamlocal-forward@openssh.com failed")
+	}
+	return err
+}
+
+// Addr returns the listener's network address.
+func (l *unixListener) Addr() net.Addr {
+	return &net.UnixAddr{
+		Name: l.socketPath,
+		Net:  "unix",
+	}
+}

vendor/golang.org/x/crypto/ssh/tcpip.go

@@ -0,0 +1,465 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math/rand"
+	"net"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+// Listen requests the remote peer open a listening socket on
+// addr. Incoming connections will be available by calling Accept on
+// the returned net.Listener. The listener must be serviced, or the
+// SSH connection may hang.
+// N must be "tcp", "tcp4", "tcp6", or "unix".
+func (c *Client) Listen(n, addr string) (net.Listener, error) {
+	switch n {
+	case "tcp", "tcp4", "tcp6":
+		laddr, err := net.ResolveTCPAddr(n, addr)
+		if err != nil {
+			return nil, err
+		}
+		return c.ListenTCP(laddr)
+	case "unix":
+		return c.ListenUnix(addr)
+	default:
+		return nil, fmt.Errorf("ssh: unsupported protocol: %s", n)
+	}
+}
+
+// Automatic port allocation is broken with OpenSSH before 6.0. See
+// also https://bugzilla.mindrot.org/show_bug.cgi?id=2017.  In
+// particular, OpenSSH 5.9 sends a channelOpenMsg with port number 0,
+// rather than the actual port number. This means you can never open
+// two different listeners with auto allocated ports. We work around
+// this by trying explicit ports until we succeed.
+
+const openSSHPrefix = "OpenSSH_"
+
+var portRandomizer = rand.New(rand.NewSource(time.Now().UnixNano()))
+
+// isBrokenOpenSSHVersion returns true if the given version string
+// specifies a version of OpenSSH that is known to have a bug in port
+// forwarding.
+func isBrokenOpenSSHVersion(versionStr string) bool {
+	i := strings.Index(versionStr, openSSHPrefix)
+	if i < 0 {
+		return false
+	}
+	i += len(openSSHPrefix)
+	j := i
+	for ; j < len(versionStr); j++ {
+		if versionStr[j] < '0' || versionStr[j] > '9' {
+			break
+		}
+	}
+	version, _ := strconv.Atoi(versionStr[i:j])
+	return version < 6
+}
+
+// autoPortListenWorkaround simulates automatic port allocation by
+// trying random ports repeatedly.
+func (c *Client) autoPortListenWorkaround(laddr *net.TCPAddr) (net.Listener, error) {
+	var sshListener net.Listener
+	var err error
+	const tries = 10
+	for i := 0; i < tries; i++ {
+		addr := *laddr
+		addr.Port = 1024 + portRandomizer.Intn(60000)
+		sshListener, err = c.ListenTCP(&addr)
+		if err == nil {
+			laddr.Port = addr.Port
+			return sshListener, err
+		}
+	}
+	return nil, fmt.Errorf("ssh: listen on random port failed after %d tries: %v", tries, err)
+}
+
+// RFC 4254 7.1
+type channelForwardMsg struct {
+	addr  string
+	rport uint32
+}
+
+// ListenTCP requests the remote peer open a listening socket
+// on laddr. Incoming connections will be available by calling
+// Accept on the returned net.Listener.
+func (c *Client) ListenTCP(laddr *net.TCPAddr) (net.Listener, error) {
+	if laddr.Port == 0 && isBrokenOpenSSHVersion(string(c.ServerVersion())) {
+		return c.autoPortListenWorkaround(laddr)
+	}
+
+	m := channelForwardMsg{
+		laddr.IP.String(),
+		uint32(laddr.Port),
+	}
+	// send message
+	ok, resp, err := c.SendRequest("tcpip-forward", true, Marshal(&m))
+	if err != nil {
+		return nil, err
+	}
+	if !ok {
+		return nil, errors.New("ssh: tcpip-forward request denied by peer")
+	}
+
+	// If the original port was 0, then the remote side will
+	// supply a real port number in the response.
+	if laddr.Port == 0 {
+		var p struct {
+			Port uint32
+		}
+		if err := Unmarshal(resp, &p); err != nil {
+			return nil, err
+		}
+		laddr.Port = int(p.Port)
+	}
+
+	// Register this forward, using the port number we obtained.
+	ch := c.forwards.add(laddr)
+
+	return &tcpListener{laddr, c, ch}, nil
+}
+
+// forwardList stores a mapping between remote
+// forward requests and the tcpListeners.
+type forwardList struct {
+	sync.Mutex
+	entries []forwardEntry
+}
+
+// forwardEntry represents an established mapping of a laddr on a
+// remote ssh server to a channel connected to a tcpListener.
+type forwardEntry struct {
+	laddr net.Addr
+	c     chan forward
+}
+
+// forward represents an incoming forwarded tcpip connection. The
+// arguments to add/remove/lookup should be address as specified in
+// the original forward-request.
+type forward struct {
+	newCh NewChannel // the ssh client channel underlying this forward
+	raddr net.Addr   // the raddr of the incoming connection
+}
+
+func (l *forwardList) add(addr net.Addr) chan forward {
+	l.Lock()
+	defer l.Unlock()
+	f := forwardEntry{
+		laddr: addr,
+		c:     make(chan forward, 1),
+	}
+	l.entries = append(l.entries, f)
+	return f.c
+}
+
+// See RFC 4254, section 7.2
+type forwardedTCPPayload struct {
+	Addr       string
+	Port       uint32
+	OriginAddr string
+	OriginPort uint32
+}
+
+// parseTCPAddr parses the originating address from the remote into a *net.TCPAddr.
+func parseTCPAddr(addr string, port uint32) (*net.TCPAddr, error) {
+	if port == 0 || port > 65535 {
+		return nil, fmt.Errorf("ssh: port number out of range: %d", port)
+	}
+	ip := net.ParseIP(string(addr))
+	if ip == nil {
+		return nil, fmt.Errorf("ssh: cannot parse IP address %q", addr)
+	}
+	return &net.TCPAddr{IP: ip, Port: int(port)}, nil
+}
+
+func (l *forwardList) handleChannels(in <-chan NewChannel) {
+	for ch := range in {
+		var (
+			laddr net.Addr
+			raddr net.Addr
+			err   error
+		)
+		switch channelType := ch.ChannelType(); channelType {
+		case "forwarded-tcpip":
+			var payload forwardedTCPPayload
+			if err = Unmarshal(ch.ExtraData(), &payload); err != nil {
+				ch.Reject(ConnectionFailed, "could not parse forwarded-tcpip payload: "+err.Error())
+				continue
+			}
+
+			// RFC 4254 section 7.2 specifies that incoming
+			// addresses should list the address, in string
+			// format. It is implied that this should be an IP
+			// address, as it would be impossible to connect to it
+			// otherwise.
+			laddr, err = parseTCPAddr(payload.Addr, payload.Port)
+			if err != nil {
+				ch.Reject(ConnectionFailed, err.Error())
+				continue
+			}
+			raddr, err = parseTCPAddr(payload.OriginAddr, payload.OriginPort)
+			if err != nil {
+				ch.Reject(ConnectionFailed, err.Error())
+				continue
+			}
+
+		case "forwarded-streamlocal@openssh.com":
+			var payload forwardedStreamLocalPayload
+			if err = Unmarshal(ch.ExtraData(), &payload); err != nil {
+				ch.Reject(ConnectionFailed, "could not parse forwarded-streamlocal@openssh.com payload: "+err.Error())
+				continue
+			}
+			laddr = &net.UnixAddr{
+				Name: payload.SocketPath,
+				Net:  "unix",
+			}
+			raddr = &net.UnixAddr{
+				Name: "@",
+				Net:  "unix",
+			}
+		default:
+			panic(fmt.Errorf("ssh: unknown channel type %s", channelType))
+		}
+		if ok := l.forward(laddr, raddr, ch); !ok {
+			// Section 7.2, implementations MUST reject spurious incoming
+			// connections.
+			ch.Reject(Prohibited, "no forward for address")
+			continue
+		}
+
+	}
+}
+
+// remove removes the forward entry, and the channel feeding its
+// listener.
+func (l *forwardList) remove(addr net.Addr) {
+	l.Lock()
+	defer l.Unlock()
+	for i, f := range l.entries {
+		if addr.Network() == f.laddr.Network() && addr.String() == f.laddr.String() {
+			l.entries = append(l.entries[:i], l.entries[i+1:]...)
+			close(f.c)
+			return
+		}
+	}
+}
+
+// closeAll closes and clears all forwards.
+func (l *forwardList) closeAll() {
+	l.Lock()
+	defer l.Unlock()
+	for _, f := range l.entries {
+		close(f.c)
+	}
+	l.entries = nil
+}
+
+func (l *forwardList) forward(laddr, raddr net.Addr, ch NewChannel) bool {
+	l.Lock()
+	defer l.Unlock()
+	for _, f := range l.entries {
+		if laddr.Network() == f.laddr.Network() && laddr.String() == f.laddr.String() {
+			f.c <- forward{newCh: ch, raddr: raddr}
+			return true
+		}
+	}
+	return false
+}
+
+type tcpListener struct {
+	laddr *net.TCPAddr
+
+	conn *Client
+	in   <-chan forward
+}
+
+// Accept waits for and returns the next connection to the listener.
+func (l *tcpListener) Accept() (net.Conn, error) {
+	s, ok := <-l.in
+	if !ok {
+		return nil, io.EOF
+	}
+	ch, incoming, err := s.newCh.Accept()
+	if err != nil {
+		return nil, err
+	}
+	go DiscardRequests(incoming)
+
+	return &chanConn{
+		Channel: ch,
+		laddr:   l.laddr,
+		raddr:   s.raddr,
+	}, nil
+}
+
+// Close closes the listener.
+func (l *tcpListener) Close() error {
+	m := channelForwardMsg{
+		l.laddr.IP.String(),
+		uint32(l.laddr.Port),
+	}
+
+	// this also closes the listener.
+	l.conn.forwards.remove(l.laddr)
+	ok, _, err := l.conn.SendRequest("cancel-tcpip-forward", true, Marshal(&m))
+	if err == nil && !ok {
+		err = errors.New("ssh: cancel-tcpip-forward failed")
+	}
+	return err
+}
+
+// Addr returns the listener's network address.
+func (l *tcpListener) Addr() net.Addr {
+	return l.laddr
+}
+
+// Dial initiates a connection to the addr from the remote host.
+// The resulting connection has a zero LocalAddr() and RemoteAddr().
+func (c *Client) Dial(n, addr string) (net.Conn, error) {
+	var ch Channel
+	switch n {
+	case "tcp", "tcp4", "tcp6":
+		// Parse the address into host and numeric port.
+		host, portString, err := net.SplitHostPort(addr)
+		if err != nil {
+			return nil, err
+		}
+		port, err := strconv.ParseUint(portString, 10, 16)
+		if err != nil {
+			return nil, err
+		}
+		ch, err = c.dial(net.IPv4zero.String(), 0, host, int(port))
+		if err != nil {
+			return nil, err
+		}
+		// Use a zero address for local and remote address.
+		zeroAddr := &net.TCPAddr{
+			IP:   net.IPv4zero,
+			Port: 0,
+		}
+		return &chanConn{
+			Channel: ch,
+			laddr:   zeroAddr,
+			raddr:   zeroAddr,
+		}, nil
+	case "unix":
+		var err error
+		ch, err = c.dialStreamLocal(addr)
+		if err != nil {
+			return nil, err
+		}
+		return &chanConn{
+			Channel: ch,
+			laddr: &net.UnixAddr{
+				Name: "@",
+				Net:  "unix",
+			},
+			raddr: &net.UnixAddr{
+				Name: addr,
+				Net:  "unix",
+			},
+		}, nil
+	default:
+		return nil, fmt.Errorf("ssh: unsupported protocol: %s", n)
+	}
+}
+
+// DialTCP connects to the remote address raddr on the network net,
+// which must be "tcp", "tcp4", or "tcp6".  If laddr is not nil, it is used
+// as the local address for the connection.
+func (c *Client) DialTCP(n string, laddr, raddr *net.TCPAddr) (net.Conn, error) {
+	if laddr == nil {
+		laddr = &net.TCPAddr{
+			IP:   net.IPv4zero,
+			Port: 0,
+		}
+	}
+	ch, err := c.dial(laddr.IP.String(), laddr.Port, raddr.IP.String(), raddr.Port)
+	if err != nil {
+		return nil, err
+	}
+	return &chanConn{
+		Channel: ch,
+		laddr:   laddr,
+		raddr:   raddr,
+	}, nil
+}
+
+// RFC 4254 7.2
+type channelOpenDirectMsg struct {
+	raddr string
+	rport uint32
+	laddr string
+	lport uint32
+}
+
+func (c *Client) dial(laddr string, lport int, raddr string, rport int) (Channel, error) {
+	msg := channelOpenDirectMsg{
+		raddr: raddr,
+		rport: uint32(rport),
+		laddr: laddr,
+		lport: uint32(lport),
+	}
+	ch, in, err := c.OpenChannel("direct-tcpip", Marshal(&msg))
+	if err != nil {
+		return nil, err
+	}
+	go DiscardRequests(in)
+	return ch, err
+}
+
+type tcpChan struct {
+	Channel // the backing channel
+}
+
+// chanConn fulfills the net.Conn interface without
+// the tcpChan having to hold laddr or raddr directly.
+type chanConn struct {
+	Channel
+	laddr, raddr net.Addr
+}
+
+// LocalAddr returns the local network address.
+func (t *chanConn) LocalAddr() net.Addr {
+	return t.laddr
+}
+
+// RemoteAddr returns the remote network address.
+func (t *chanConn) RemoteAddr() net.Addr {
+	return t.raddr
+}
+
+// SetDeadline sets the read and write deadlines associated
+// with the connection.
+func (t *chanConn) SetDeadline(deadline time.Time) error {
+	if err := t.SetReadDeadline(deadline); err != nil {
+		return err
+	}
+	return t.SetWriteDeadline(deadline)
+}
+
+// SetReadDeadline sets the read deadline.
+// A zero value for t means Read will not time out.
+// After the deadline, the error from Read will implement net.Error
+// with Timeout() == true.
+func (t *chanConn) SetReadDeadline(deadline time.Time) error {
+	// for compatibility with previous version,
+	// the error message contains "tcpChan"
+	return errors.New("ssh: tcpChan: deadline not supported")
+}
+
+// SetWriteDeadline exists to satisfy the net.Conn interface
+// but is not implemented by this type.  It always returns an error.
+func (t *chanConn) SetWriteDeadline(deadline time.Time) error {
+	return errors.New("ssh: tcpChan: deadline not supported")
+}

vendor/golang.org/x/crypto/ssh/terminal/terminal.go

@@ -0,0 +1,951 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package terminal
+
+import (
+	"bytes"
+	"io"
+	"sync"
+	"unicode/utf8"
+)
+
+// EscapeCodes contains escape sequences that can be written to the terminal in
+// order to achieve different styles of text.
+type EscapeCodes struct {
+	// Foreground colors
+	Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte
+
+	// Reset all attributes
+	Reset []byte
+}
+
+var vt100EscapeCodes = EscapeCodes{
+	Black:   []byte{keyEscape, '[', '3', '0', 'm'},
+	Red:     []byte{keyEscape, '[', '3', '1', 'm'},
+	Green:   []byte{keyEscape, '[', '3', '2', 'm'},
+	Yellow:  []byte{keyEscape, '[', '3', '3', 'm'},
+	Blue:    []byte{keyEscape, '[', '3', '4', 'm'},
+	Magenta: []byte{keyEscape, '[', '3', '5', 'm'},
+	Cyan:    []byte{keyEscape, '[', '3', '6', 'm'},
+	White:   []byte{keyEscape, '[', '3', '7', 'm'},
+
+	Reset: []byte{keyEscape, '[', '0', 'm'},
+}
+
+// Terminal contains the state for running a VT100 terminal that is capable of
+// reading lines of input.
+type Terminal struct {
+	// AutoCompleteCallback, if non-null, is called for each keypress with
+	// the full input line and the current position of the cursor (in
+	// bytes, as an index into |line|). If it returns ok=false, the key
+	// press is processed normally. Otherwise it returns a replacement line
+	// and the new cursor position.
+	AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool)
+
+	// Escape contains a pointer to the escape codes for this terminal.
+	// It's always a valid pointer, although the escape codes themselves
+	// may be empty if the terminal doesn't support them.
+	Escape *EscapeCodes
+
+	// lock protects the terminal and the state in this object from
+	// concurrent processing of a key press and a Write() call.
+	lock sync.Mutex
+
+	c      io.ReadWriter
+	prompt []rune
+
+	// line is the current line being entered.
+	line []rune
+	// pos is the logical position of the cursor in line
+	pos int
+	// echo is true if local echo is enabled
+	echo bool
+	// pasteActive is true iff there is a bracketed paste operation in
+	// progress.
+	pasteActive bool
+
+	// cursorX contains the current X value of the cursor where the left
+	// edge is 0. cursorY contains the row number where the first row of
+	// the current line is 0.
+	cursorX, cursorY int
+	// maxLine is the greatest value of cursorY so far.
+	maxLine int
+
+	termWidth, termHeight int
+
+	// outBuf contains the terminal data to be sent.
+	outBuf []byte
+	// remainder contains the remainder of any partial key sequences after
+	// a read. It aliases into inBuf.
+	remainder []byte
+	inBuf     [256]byte
+
+	// history contains previously entered commands so that they can be
+	// accessed with the up and down keys.
+	history stRingBuffer
+	// historyIndex stores the currently accessed history entry, where zero
+	// means the immediately previous entry.
+	historyIndex int
+	// When navigating up and down the history it's possible to return to
+	// the incomplete, initial line. That value is stored in
+	// historyPending.
+	historyPending string
+}
+
+// NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
+// a local terminal, that terminal must first have been put into raw mode.
+// prompt is a string that is written at the start of each input line (i.e.
+// "> ").
+func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
+	return &Terminal{
+		Escape:       &vt100EscapeCodes,
+		c:            c,
+		prompt:       []rune(prompt),
+		termWidth:    80,
+		termHeight:   24,
+		echo:         true,
+		historyIndex: -1,
+	}
+}
+
+const (
+	keyCtrlD     = 4
+	keyCtrlU     = 21
+	keyEnter     = '\r'
+	keyEscape    = 27
+	keyBackspace = 127
+	keyUnknown   = 0xd800 /* UTF-16 surrogate area */ + iota
+	keyUp
+	keyDown
+	keyLeft
+	keyRight
+	keyAltLeft
+	keyAltRight
+	keyHome
+	keyEnd
+	keyDeleteWord
+	keyDeleteLine
+	keyClearScreen
+	keyPasteStart
+	keyPasteEnd
+)
+
+var (
+	crlf       = []byte{'\r', '\n'}
+	pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
+	pasteEnd   = []byte{keyEscape, '[', '2', '0', '1', '~'}
+)
+
+// bytesToKey tries to parse a key sequence from b. If successful, it returns
+// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
+func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
+	if len(b) == 0 {
+		return utf8.RuneError, nil
+	}
+
+	if !pasteActive {
+		switch b[0] {
+		case 1: // ^A
+			return keyHome, b[1:]
+		case 5: // ^E
+			return keyEnd, b[1:]
+		case 8: // ^H
+			return keyBackspace, b[1:]
+		case 11: // ^K
+			return keyDeleteLine, b[1:]
+		case 12: // ^L
+			return keyClearScreen, b[1:]
+		case 23: // ^W
+			return keyDeleteWord, b[1:]
+		}
+	}
+
+	if b[0] != keyEscape {
+		if !utf8.FullRune(b) {
+			return utf8.RuneError, b
+		}
+		r, l := utf8.DecodeRune(b)
+		return r, b[l:]
+	}
+
+	if !pasteActive && len(b) >= 3 && b[0] == keyEscape && b[1] == '[' {
+		switch b[2] {
+		case 'A':
+			return keyUp, b[3:]
+		case 'B':
+			return keyDown, b[3:]
+		case 'C':
+			return keyRight, b[3:]
+		case 'D':
+			return keyLeft, b[3:]
+		case 'H':
+			return keyHome, b[3:]
+		case 'F':
+			return keyEnd, b[3:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && b[0] == keyEscape && b[1] == '[' && b[2] == '1' && b[3] == ';' && b[4] == '3' {
+		switch b[5] {
+		case 'C':
+			return keyAltRight, b[6:]
+		case 'D':
+			return keyAltLeft, b[6:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteStart) {
+		return keyPasteStart, b[6:]
+	}
+
+	if pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteEnd) {
+		return keyPasteEnd, b[6:]
+	}
+
+	// If we get here then we have a key that we don't recognise, or a
+	// partial sequence. It's not clear how one should find the end of a
+	// sequence without knowing them all, but it seems that [a-zA-Z~] only
+	// appears at the end of a sequence.
+	for i, c := range b[0:] {
+		if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c == '~' {
+			return keyUnknown, b[i+1:]
+		}
+	}
+
+	return utf8.RuneError, b
+}
+
+// queue appends data to the end of t.outBuf
+func (t *Terminal) queue(data []rune) {
+	t.outBuf = append(t.outBuf, []byte(string(data))...)
+}
+
+var eraseUnderCursor = []rune{' ', keyEscape, '[', 'D'}
+var space = []rune{' '}
+
+func isPrintable(key rune) bool {
+	isInSurrogateArea := key >= 0xd800 && key <= 0xdbff
+	return key >= 32 && !isInSurrogateArea
+}
+
+// moveCursorToPos appends data to t.outBuf which will move the cursor to the
+// given, logical position in the text.
+func (t *Terminal) moveCursorToPos(pos int) {
+	if !t.echo {
+		return
+	}
+
+	x := visualLength(t.prompt) + pos
+	y := x / t.termWidth
+	x = x % t.termWidth
+
+	up := 0
+	if y < t.cursorY {
+		up = t.cursorY - y
+	}
+
+	down := 0
+	if y > t.cursorY {
+		down = y - t.cursorY
+	}
+
+	left := 0
+	if x < t.cursorX {
+		left = t.cursorX - x
+	}
+
+	right := 0
+	if x > t.cursorX {
+		right = x - t.cursorX
+	}
+
+	t.cursorX = x
+	t.cursorY = y
+	t.move(up, down, left, right)
+}
+
+func (t *Terminal) move(up, down, left, right int) {
+	movement := make([]rune, 3*(up+down+left+right))
+	m := movement
+	for i := 0; i < up; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'A'
+		m = m[3:]
+	}
+	for i := 0; i < down; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'B'
+		m = m[3:]
+	}
+	for i := 0; i < left; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'D'
+		m = m[3:]
+	}
+	for i := 0; i < right; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'C'
+		m = m[3:]
+	}
+
+	t.queue(movement)
+}
+
+func (t *Terminal) clearLineToRight() {
+	op := []rune{keyEscape, '[', 'K'}
+	t.queue(op)
+}
+
+const maxLineLength = 4096
+
+func (t *Terminal) setLine(newLine []rune, newPos int) {
+	if t.echo {
+		t.moveCursorToPos(0)
+		t.writeLine(newLine)
+		for i := len(newLine); i < len(t.line); i++ {
+			t.writeLine(space)
+		}
+		t.moveCursorToPos(newPos)
+	}
+	t.line = newLine
+	t.pos = newPos
+}
+
+func (t *Terminal) advanceCursor(places int) {
+	t.cursorX += places
+	t.cursorY += t.cursorX / t.termWidth
+	if t.cursorY > t.maxLine {
+		t.maxLine = t.cursorY
+	}
+	t.cursorX = t.cursorX % t.termWidth
+
+	if places > 0 && t.cursorX == 0 {
+		// Normally terminals will advance the current position
+		// when writing a character. But that doesn't happen
+		// for the last character in a line. However, when
+		// writing a character (except a new line) that causes
+		// a line wrap, the position will be advanced two
+		// places.
+		//
+		// So, if we are stopping at the end of a line, we
+		// need to write a newline so that our cursor can be
+		// advanced to the next line.
+		t.outBuf = append(t.outBuf, '\r', '\n')
+	}
+}
+
+func (t *Terminal) eraseNPreviousChars(n int) {
+	if n == 0 {
+		return
+	}
+
+	if t.pos < n {
+		n = t.pos
+	}
+	t.pos -= n
+	t.moveCursorToPos(t.pos)
+
+	copy(t.line[t.pos:], t.line[n+t.pos:])
+	t.line = t.line[:len(t.line)-n]
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+		for i := 0; i < n; i++ {
+			t.queue(space)
+		}
+		t.advanceCursor(n)
+		t.moveCursorToPos(t.pos)
+	}
+}
+
+// countToLeftWord returns then number of characters from the cursor to the
+// start of the previous word.
+func (t *Terminal) countToLeftWord() int {
+	if t.pos == 0 {
+		return 0
+	}
+
+	pos := t.pos - 1
+	for pos > 0 {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos--
+	}
+	for pos > 0 {
+		if t.line[pos] == ' ' {
+			pos++
+			break
+		}
+		pos--
+	}
+
+	return t.pos - pos
+}
+
+// countToRightWord returns then number of characters from the cursor to the
+// start of the next word.
+func (t *Terminal) countToRightWord() int {
+	pos := t.pos
+	for pos < len(t.line) {
+		if t.line[pos] == ' ' {
+			break
+		}
+		pos++
+	}
+	for pos < len(t.line) {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos++
+	}
+	return pos - t.pos
+}
+
+// visualLength returns the number of visible glyphs in s.
+func visualLength(runes []rune) int {
+	inEscapeSeq := false
+	length := 0
+
+	for _, r := range runes {
+		switch {
+		case inEscapeSeq:
+			if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') {
+				inEscapeSeq = false
+			}
+		case r == '\x1b':
+			inEscapeSeq = true
+		default:
+			length++
+		}
+	}
+
+	return length
+}
+
+// handleKey processes the given key and, optionally, returns a line of text
+// that the user has entered.
+func (t *Terminal) handleKey(key rune) (line string, ok bool) {
+	if t.pasteActive && key != keyEnter {
+		t.addKeyToLine(key)
+		return
+	}
+
+	switch key {
+	case keyBackspace:
+		if t.pos == 0 {
+			return
+		}
+		t.eraseNPreviousChars(1)
+	case keyAltLeft:
+		// move left by a word.
+		t.pos -= t.countToLeftWord()
+		t.moveCursorToPos(t.pos)
+	case keyAltRight:
+		// move right by a word.
+		t.pos += t.countToRightWord()
+		t.moveCursorToPos(t.pos)
+	case keyLeft:
+		if t.pos == 0 {
+			return
+		}
+		t.pos--
+		t.moveCursorToPos(t.pos)
+	case keyRight:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos++
+		t.moveCursorToPos(t.pos)
+	case keyHome:
+		if t.pos == 0 {
+			return
+		}
+		t.pos = 0
+		t.moveCursorToPos(t.pos)
+	case keyEnd:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos = len(t.line)
+		t.moveCursorToPos(t.pos)
+	case keyUp:
+		entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1)
+		if !ok {
+			return "", false
+		}
+		if t.historyIndex == -1 {
+			t.historyPending = string(t.line)
+		}
+		t.historyIndex++
+		runes := []rune(entry)
+		t.setLine(runes, len(runes))
+	case keyDown:
+		switch t.historyIndex {
+		case -1:
+			return
+		case 0:
+			runes := []rune(t.historyPending)
+			t.setLine(runes, len(runes))
+			t.historyIndex--
+		default:
+			entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1)
+			if ok {
+				t.historyIndex--
+				runes := []rune(entry)
+				t.setLine(runes, len(runes))
+			}
+		}
+	case keyEnter:
+		t.moveCursorToPos(len(t.line))
+		t.queue([]rune("\r\n"))
+		line = string(t.line)
+		ok = true
+		t.line = t.line[:0]
+		t.pos = 0
+		t.cursorX = 0
+		t.cursorY = 0
+		t.maxLine = 0
+	case keyDeleteWord:
+		// Delete zero or more spaces and then one or more characters.
+		t.eraseNPreviousChars(t.countToLeftWord())
+	case keyDeleteLine:
+		// Delete everything from the current cursor position to the
+		// end of line.
+		for i := t.pos; i < len(t.line); i++ {
+			t.queue(space)
+			t.advanceCursor(1)
+		}
+		t.line = t.line[:t.pos]
+		t.moveCursorToPos(t.pos)
+	case keyCtrlD:
+		// Erase the character under the current position.
+		// The EOF case when the line is empty is handled in
+		// readLine().
+		if t.pos < len(t.line) {
+			t.pos++
+			t.eraseNPreviousChars(1)
+		}
+	case keyCtrlU:
+		t.eraseNPreviousChars(t.pos)
+	case keyClearScreen:
+		// Erases the screen and moves the cursor to the home position.
+		t.queue([]rune("\x1b[2J\x1b[H"))
+		t.queue(t.prompt)
+		t.cursorX, t.cursorY = 0, 0
+		t.advanceCursor(visualLength(t.prompt))
+		t.setLine(t.line, t.pos)
+	default:
+		if t.AutoCompleteCallback != nil {
+			prefix := string(t.line[:t.pos])
+			suffix := string(t.line[t.pos:])
+
+			t.lock.Unlock()
+			newLine, newPos, completeOk := t.AutoCompleteCallback(prefix+suffix, len(prefix), key)
+			t.lock.Lock()
+
+			if completeOk {
+				t.setLine([]rune(newLine), utf8.RuneCount([]byte(newLine)[:newPos]))
+				return
+			}
+		}
+		if !isPrintable(key) {
+			return
+		}
+		if len(t.line) == maxLineLength {
+			return
+		}
+		t.addKeyToLine(key)
+	}
+	return
+}
+
+// addKeyToLine inserts the given key at the current position in the current
+// line.
+func (t *Terminal) addKeyToLine(key rune) {
+	if len(t.line) == cap(t.line) {
+		newLine := make([]rune, len(t.line), 2*(1+len(t.line)))
+		copy(newLine, t.line)
+		t.line = newLine
+	}
+	t.line = t.line[:len(t.line)+1]
+	copy(t.line[t.pos+1:], t.line[t.pos:])
+	t.line[t.pos] = key
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+	}
+	t.pos++
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) writeLine(line []rune) {
+	for len(line) != 0 {
+		remainingOnLine := t.termWidth - t.cursorX
+		todo := len(line)
+		if todo > remainingOnLine {
+			todo = remainingOnLine
+		}
+		t.queue(line[:todo])
+		t.advanceCursor(visualLength(line[:todo]))
+		line = line[todo:]
+	}
+}
+
+// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
+func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
+	for len(buf) > 0 {
+		i := bytes.IndexByte(buf, '\n')
+		todo := len(buf)
+		if i >= 0 {
+			todo = i
+		}
+
+		var nn int
+		nn, err = w.Write(buf[:todo])
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		buf = buf[todo:]
+
+		if i >= 0 {
+			if _, err = w.Write(crlf); err != nil {
+				return n, err
+			}
+			n += 1
+			buf = buf[1:]
+		}
+	}
+
+	return n, nil
+}
+
+func (t *Terminal) Write(buf []byte) (n int, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		// This is the easy case: there's nothing on the screen that we
+		// have to move out of the way.
+		return writeWithCRLF(t.c, buf)
+	}
+
+	// We have a prompt and possibly user input on the screen. We
+	// have to clear it first.
+	t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
+	t.cursorX = 0
+	t.clearLineToRight()
+
+	for t.cursorY > 0 {
+		t.move(1 /* up */, 0, 0, 0)
+		t.cursorY--
+		t.clearLineToRight()
+	}
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+
+	if n, err = writeWithCRLF(t.c, buf); err != nil {
+		return
+	}
+
+	t.writeLine(t.prompt)
+	if t.echo {
+		t.writeLine(t.line)
+	}
+
+	t.moveCursorToPos(t.pos)
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+	return
+}
+
+// ReadPassword temporarily changes the prompt and reads a password, without
+// echo, from the terminal.
+func (t *Terminal) ReadPassword(prompt string) (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	oldPrompt := t.prompt
+	t.prompt = []rune(prompt)
+	t.echo = false
+
+	line, err = t.readLine()
+
+	t.prompt = oldPrompt
+	t.echo = true
+
+	return
+}
+
+// ReadLine returns a line of input from the terminal.
+func (t *Terminal) ReadLine() (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	return t.readLine()
+}
+
+func (t *Terminal) readLine() (line string, err error) {
+	// t.lock must be held at this point
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		t.writeLine(t.prompt)
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+	}
+
+	lineIsPasted := t.pasteActive
+
+	for {
+		rest := t.remainder
+		lineOk := false
+		for !lineOk {
+			var key rune
+			key, rest = bytesToKey(rest, t.pasteActive)
+			if key == utf8.RuneError {
+				break
+			}
+			if !t.pasteActive {
+				if key == keyCtrlD {
+					if len(t.line) == 0 {
+						return "", io.EOF
+					}
+				}
+				if key == keyPasteStart {
+					t.pasteActive = true
+					if len(t.line) == 0 {
+						lineIsPasted = true
+					}
+					continue
+				}
+			} else if key == keyPasteEnd {
+				t.pasteActive = false
+				continue
+			}
+			if !t.pasteActive {
+				lineIsPasted = false
+			}
+			line, lineOk = t.handleKey(key)
+		}
+		if len(rest) > 0 {
+			n := copy(t.inBuf[:], rest)
+			t.remainder = t.inBuf[:n]
+		} else {
+			t.remainder = nil
+		}
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+		if lineOk {
+			if t.echo {
+				t.historyIndex = -1
+				t.history.Add(line)
+			}
+			if lineIsPasted {
+				err = ErrPasteIndicator
+			}
+			return
+		}
+
+		// t.remainder is a slice at the beginning of t.inBuf
+		// containing a partial key sequence
+		readBuf := t.inBuf[len(t.remainder):]
+		var n int
+
+		t.lock.Unlock()
+		n, err = t.c.Read(readBuf)
+		t.lock.Lock()
+
+		if err != nil {
+			return
+		}
+
+		t.remainder = t.inBuf[:n+len(t.remainder)]
+	}
+}
+
+// SetPrompt sets the prompt to be used when reading subsequent lines.
+func (t *Terminal) SetPrompt(prompt string) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	t.prompt = []rune(prompt)
+}
+
+func (t *Terminal) clearAndRepaintLinePlusNPrevious(numPrevLines int) {
+	// Move cursor to column zero at the start of the line.
+	t.move(t.cursorY, 0, t.cursorX, 0)
+	t.cursorX, t.cursorY = 0, 0
+	t.clearLineToRight()
+	for t.cursorY < numPrevLines {
+		// Move down a line
+		t.move(0, 1, 0, 0)
+		t.cursorY++
+		t.clearLineToRight()
+	}
+	// Move back to beginning.
+	t.move(t.cursorY, 0, 0, 0)
+	t.cursorX, t.cursorY = 0, 0
+
+	t.queue(t.prompt)
+	t.advanceCursor(visualLength(t.prompt))
+	t.writeLine(t.line)
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) SetSize(width, height int) error {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if width == 0 {
+		width = 1
+	}
+
+	oldWidth := t.termWidth
+	t.termWidth, t.termHeight = width, height
+
+	switch {
+	case width == oldWidth:
+		// If the width didn't change then nothing else needs to be
+		// done.
+		return nil
+	case len(t.line) == 0 && t.cursorX == 0 && t.cursorY == 0:
+		// If there is nothing on current line and no prompt printed,
+		// just do nothing
+		return nil
+	case width < oldWidth:
+		// Some terminals (e.g. xterm) will truncate lines that were
+		// too long when shinking. Others, (e.g. gnome-terminal) will
+		// attempt to wrap them. For the former, repainting t.maxLine
+		// works great, but that behaviour goes badly wrong in the case
+		// of the latter because they have doubled every full line.
+
+		// We assume that we are working on a terminal that wraps lines
+		// and adjust the cursor position based on every previous line
+		// wrapping and turning into two. This causes the prompt on
+		// xterms to move upwards, which isn't great, but it avoids a
+		// huge mess with gnome-terminal.
+		if t.cursorX >= t.termWidth {
+			t.cursorX = t.termWidth - 1
+		}
+		t.cursorY *= 2
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine * 2)
+	case width > oldWidth:
+		// If the terminal expands then our position calculations will
+		// be wrong in the future because we think the cursor is
+		// |t.pos| chars into the string, but there will be a gap at
+		// the end of any wrapped line.
+		//
+		// But the position will actually be correct until we move, so
+		// we can move back to the beginning and repaint everything.
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine)
+	}
+
+	_, err := t.c.Write(t.outBuf)
+	t.outBuf = t.outBuf[:0]
+	return err
+}
+
+type pasteIndicatorError struct{}
+
+func (pasteIndicatorError) Error() string {
+	return "terminal: ErrPasteIndicator not correctly handled"
+}
+
+// ErrPasteIndicator may be returned from ReadLine as the error, in addition
+// to valid line data. It indicates that bracketed paste mode is enabled and
+// that the returned line consists only of pasted data. Programs may wish to
+// interpret pasted data more literally than typed data.
+var ErrPasteIndicator = pasteIndicatorError{}
+
+// SetBracketedPasteMode requests that the terminal bracket paste operations
+// with markers. Not all terminals support this but, if it is supported, then
+// enabling this mode will stop any autocomplete callback from running due to
+// pastes. Additionally, any lines that are completely pasted will be returned
+// from ReadLine with the error set to ErrPasteIndicator.
+func (t *Terminal) SetBracketedPasteMode(on bool) {
+	if on {
+		io.WriteString(t.c, "\x1b[?2004h")
+	} else {
+		io.WriteString(t.c, "\x1b[?2004l")
+	}
+}
+
+// stRingBuffer is a ring buffer of strings.
+type stRingBuffer struct {
+	// entries contains max elements.
+	entries []string
+	max     int
+	// head contains the index of the element most recently added to the ring.
+	head int
+	// size contains the number of elements in the ring.
+	size int
+}
+
+func (s *stRingBuffer) Add(a string) {
+	if s.entries == nil {
+		const defaultNumEntries = 100
+		s.entries = make([]string, defaultNumEntries)
+		s.max = defaultNumEntries
+	}
+
+	s.head = (s.head + 1) % s.max
+	s.entries[s.head] = a
+	if s.size < s.max {
+		s.size++
+	}
+}
+
+// NthPreviousEntry returns the value passed to the nth previous call to Add.
+// If n is zero then the immediately prior value is returned, if one, then the
+// next most recent, and so on. If such an element doesn't exist then ok is
+// false.
+func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
+	if n >= s.size {
+		return "", false
+	}
+	index := s.head - n
+	if index < 0 {
+		index += s.max
+	}
+	return s.entries[index], true
+}
+
+// readPasswordLine reads from reader until it finds \n or io.EOF.
+// The slice returned does not include the \n.
+// readPasswordLine also ignores any \r it finds.
+func readPasswordLine(reader io.Reader) ([]byte, error) {
+	var buf [1]byte
+	var ret []byte
+
+	for {
+		n, err := reader.Read(buf[:])
+		if n > 0 {
+			switch buf[0] {
+			case '\n':
+				return ret, nil
+			case '\r':
+				// remove \r from passwords on Windows
+			default:
+				ret = append(ret, buf[0])
+			}
+			continue
+		}
+		if err != nil {
+			if err == io.EOF && len(ret) > 0 {
+				return ret, nil
+			}
+			return ret, err
+		}
+	}
+}

vendor/golang.org/x/crypto/ssh/terminal/util.go

@@ -0,0 +1,116 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux,!appengine netbsd openbsd
+
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+// 	oldState, err := terminal.MakeRaw(0)
+// 	if err != nil {
+// 	        panic(err)
+// 	}
+// 	defer terminal.Restore(0, oldState)
+package terminal // import "golang.org/x/crypto/ssh/terminal"
+
+import (
+	"golang.org/x/sys/unix"
+)
+
+// State contains the state of a terminal.
+type State struct {
+	termios unix.Termios
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	_, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	return err == nil
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	if err != nil {
+		return nil, err
+	}
+
+	oldState := State{termios: *termios}
+
+	// This attempts to replicate the behaviour documented for cfmakeraw in
+	// the termios(3) manpage.
+	termios.Iflag &^= unix.IGNBRK | unix.BRKINT | unix.PARMRK | unix.ISTRIP | unix.INLCR | unix.IGNCR | unix.ICRNL | unix.IXON
+	termios.Oflag &^= unix.OPOST
+	termios.Lflag &^= unix.ECHO | unix.ECHONL | unix.ICANON | unix.ISIG | unix.IEXTEN
+	termios.Cflag &^= unix.CSIZE | unix.PARENB
+	termios.Cflag |= unix.CS8
+	termios.Cc[unix.VMIN] = 1
+	termios.Cc[unix.VTIME] = 0
+	if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, termios); err != nil {
+		return nil, err
+	}
+
+	return &oldState, nil
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{termios: *termios}, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, state *State) error {
+	return unix.IoctlSetTermios(fd, ioctlWriteTermios, &state.termios)
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
+	if err != nil {
+		return -1, -1, err
+	}
+	return int(ws.Col), int(ws.Row), nil
+}
+
+// passwordReader is an io.Reader that reads from a specific file descriptor.
+type passwordReader int
+
+func (r passwordReader) Read(buf []byte) (int, error) {
+	return unix.Read(int(r), buf)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	if err != nil {
+		return nil, err
+	}
+
+	newState := *termios
+	newState.Lflag &^= unix.ECHO
+	newState.Lflag |= unix.ICANON | unix.ISIG
+	newState.Iflag |= unix.ICRNL
+	if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, &newState); err != nil {
+		return nil, err
+	}
+
+	defer func() {
+		unix.IoctlSetTermios(fd, ioctlWriteTermios, termios)
+	}()
+
+	return readPasswordLine(passwordReader(fd))
+}

vendor/golang.org/x/crypto/ssh/terminal/util_bsd.go

@@ -0,0 +1,12 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd netbsd openbsd
+
+package terminal
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TIOCGETA
+const ioctlWriteTermios = unix.TIOCSETA

vendor/golang.org/x/crypto/ssh/terminal/util_linux.go

@@ -0,0 +1,10 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package terminal
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+const ioctlWriteTermios = unix.TCSETS

vendor/golang.org/x/crypto/ssh/terminal/util_plan9.go

@@ -0,0 +1,58 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+// 	oldState, err := terminal.MakeRaw(0)
+// 	if err != nil {
+// 	        panic(err)
+// 	}
+// 	defer terminal.Restore(0, oldState)
+package terminal
+
+import (
+	"fmt"
+	"runtime"
+)
+
+type State struct{}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	return false
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, state *State) error {
+	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}

vendor/golang.org/x/crypto/ssh/terminal/util_solaris.go

@@ -0,0 +1,128 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build solaris
+
+package terminal // import "golang.org/x/crypto/ssh/terminal"
+
+import (
+	"golang.org/x/sys/unix"
+	"io"
+	"syscall"
+)
+
+// State contains the state of a terminal.
+type State struct {
+	state *unix.Termios
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	_, err := unix.IoctlGetTermio(fd, unix.TCGETA)
+	return err == nil
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	// see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
+	val, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+	oldState := *val
+
+	newState := oldState
+	newState.Lflag &^= syscall.ECHO
+	newState.Lflag |= syscall.ICANON | syscall.ISIG
+	newState.Iflag |= syscall.ICRNL
+	err = unix.IoctlSetTermios(fd, unix.TCSETS, &newState)
+	if err != nil {
+		return nil, err
+	}
+
+	defer unix.IoctlSetTermios(fd, unix.TCSETS, &oldState)
+
+	var buf [16]byte
+	var ret []byte
+	for {
+		n, err := syscall.Read(fd, buf[:])
+		if err != nil {
+			return nil, err
+		}
+		if n == 0 {
+			if len(ret) == 0 {
+				return nil, io.EOF
+			}
+			break
+		}
+		if buf[n-1] == '\n' {
+			n--
+		}
+		ret = append(ret, buf[:n]...)
+		if n < len(buf) {
+			break
+		}
+	}
+
+	return ret, nil
+}
+
+// MakeRaw puts the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+// see http://cr.illumos.org/~webrev/andy_js/1060/
+func MakeRaw(fd int) (*State, error) {
+	oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+	oldTermios := *oldTermiosPtr
+
+	newTermios := oldTermios
+	newTermios.Iflag &^= syscall.IGNBRK | syscall.BRKINT | syscall.PARMRK | syscall.ISTRIP | syscall.INLCR | syscall.IGNCR | syscall.ICRNL | syscall.IXON
+	newTermios.Oflag &^= syscall.OPOST
+	newTermios.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG | syscall.IEXTEN
+	newTermios.Cflag &^= syscall.CSIZE | syscall.PARENB
+	newTermios.Cflag |= syscall.CS8
+	newTermios.Cc[unix.VMIN] = 1
+	newTermios.Cc[unix.VTIME] = 0
+
+	if err := unix.IoctlSetTermios(fd, unix.TCSETS, &newTermios); err != nil {
+		return nil, err
+	}
+
+	return &State{
+		state: oldTermiosPtr,
+	}, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, oldState *State) error {
+	return unix.IoctlSetTermios(fd, unix.TCSETS, oldState.state)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{
+		state: oldTermiosPtr,
+	}, nil
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
+	if err != nil {
+		return 0, 0, err
+	}
+	return int(ws.Col), int(ws.Row), nil
+}

vendor/golang.org/x/crypto/ssh/terminal/util_windows.go

@@ -0,0 +1,102 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+// 	oldState, err := terminal.MakeRaw(0)
+// 	if err != nil {
+// 	        panic(err)
+// 	}
+// 	defer terminal.Restore(0, oldState)
+package terminal
+
+import (
+	"golang.org/x/sys/windows"
+)
+
+type State struct {
+	mode uint32
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	var st uint32
+	err := windows.GetConsoleMode(windows.Handle(fd), &st)
+	return err == nil
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	raw := st &^ (windows.ENABLE_ECHO_INPUT | windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	if err := windows.SetConsoleMode(windows.Handle(fd), raw); err != nil {
+		return nil, err
+	}
+	return &State{st}, nil
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	return &State{st}, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, state *State) error {
+	return windows.SetConsoleMode(windows.Handle(fd), state.mode)
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	var info windows.ConsoleScreenBufferInfo
+	if err := windows.GetConsoleScreenBufferInfo(windows.Handle(fd), &info); err != nil {
+		return 0, 0, err
+	}
+	return int(info.Size.X), int(info.Size.Y), nil
+}
+
+// passwordReader is an io.Reader that reads from a specific Windows HANDLE.
+type passwordReader int
+
+func (r passwordReader) Read(buf []byte) (int, error) {
+	return windows.Read(windows.Handle(r), buf)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	old := st
+
+	st &^= (windows.ENABLE_ECHO_INPUT)
+	st |= (windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	if err := windows.SetConsoleMode(windows.Handle(fd), st); err != nil {
+		return nil, err
+	}
+
+	defer func() {
+		windows.SetConsoleMode(windows.Handle(fd), old)
+	}()
+
+	return readPasswordLine(passwordReader(fd))
+}

vendor/golang.org/x/crypto/ssh/transport.go

@@ -0,0 +1,375 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssh
+
+import (
+	"bufio"
+	"errors"
+	"io"
+	"log"
+)
+
+// debugTransport if set, will print packet types as they go over the
+// wire. No message decoding is done, to minimize the impact on timing.
+const debugTransport = false
+
+const (
+	gcmCipherID    = "aes128-gcm@openssh.com"
+	aes128cbcID    = "aes128-cbc"
+	tripledescbcID = "3des-cbc"
+)
+
+// packetConn represents a transport that implements packet based
+// operations.
+type packetConn interface {
+	// Encrypt and send a packet of data to the remote peer.
+	writePacket(packet []byte) error
+
+	// Read a packet from the connection. The read is blocking,
+	// i.e. if error is nil, then the returned byte slice is
+	// always non-empty.
+	readPacket() ([]byte, error)
+
+	// Close closes the write-side of the connection.
+	Close() error
+}
+
+// transport is the keyingTransport that implements the SSH packet
+// protocol.
+type transport struct {
+	reader connectionState
+	writer connectionState
+
+	bufReader *bufio.Reader
+	bufWriter *bufio.Writer
+	rand      io.Reader
+	isClient  bool
+	io.Closer
+}
+
+// packetCipher represents a combination of SSH encryption/MAC
+// protocol.  A single instance should be used for one direction only.
+type packetCipher interface {
+	// writePacket encrypts the packet and writes it to w. The
+	// contents of the packet are generally scrambled.
+	writePacket(seqnum uint32, w io.Writer, rand io.Reader, packet []byte) error
+
+	// readPacket reads and decrypts a packet of data. The
+	// returned packet may be overwritten by future calls of
+	// readPacket.
+	readPacket(seqnum uint32, r io.Reader) ([]byte, error)
+}
+
+// connectionState represents one side (read or write) of the
+// connection. This is necessary because each direction has its own
+// keys, and can even have its own algorithms
+type connectionState struct {
+	packetCipher
+	seqNum           uint32
+	dir              direction
+	pendingKeyChange chan packetCipher
+}
+
+// prepareKeyChange sets up key material for a keychange. The key changes in
+// both directions are triggered by reading and writing a msgNewKey packet
+// respectively.
+func (t *transport) prepareKeyChange(algs *algorithms, kexResult *kexResult) error {
+	if ciph, err := newPacketCipher(t.reader.dir, algs.r, kexResult); err != nil {
+		return err
+	} else {
+		t.reader.pendingKeyChange <- ciph
+	}
+
+	if ciph, err := newPacketCipher(t.writer.dir, algs.w, kexResult); err != nil {
+		return err
+	} else {
+		t.writer.pendingKeyChange <- ciph
+	}
+
+	return nil
+}
+
+func (t *transport) printPacket(p []byte, write bool) {
+	if len(p) == 0 {
+		return
+	}
+	who := "server"
+	if t.isClient {
+		who = "client"
+	}
+	what := "read"
+	if write {
+		what = "write"
+	}
+
+	log.Println(what, who, p[0])
+}
+
+// Read and decrypt next packet.
+func (t *transport) readPacket() (p []byte, err error) {
+	for {
+		p, err = t.reader.readPacket(t.bufReader)
+		if err != nil {
+			break
+		}
+		if len(p) == 0 || (p[0] != msgIgnore && p[0] != msgDebug) {
+			break
+		}
+	}
+	if debugTransport {
+		t.printPacket(p, false)
+	}
+
+	return p, err
+}
+
+func (s *connectionState) readPacket(r *bufio.Reader) ([]byte, error) {
+	packet, err := s.packetCipher.readPacket(s.seqNum, r)
+	s.seqNum++
+	if err == nil && len(packet) == 0 {
+		err = errors.New("ssh: zero length packet")
+	}
+
+	if len(packet) > 0 {
+		switch packet[0] {
+		case msgNewKeys:
+			select {
+			case cipher := <-s.pendingKeyChange:
+				s.packetCipher = cipher
+			default:
+				return nil, errors.New("ssh: got bogus newkeys message.")
+			}
+
+		case msgDisconnect:
+			// Transform a disconnect message into an
+			// error. Since this is lowest level at which
+			// we interpret message types, doing it here
+			// ensures that we don't have to handle it
+			// elsewhere.
+			var msg disconnectMsg
+			if err := Unmarshal(packet, &msg); err != nil {
+				return nil, err
+			}
+			return nil, &msg
+		}
+	}
+
+	// The packet may point to an internal buffer, so copy the
+	// packet out here.
+	fresh := make([]byte, len(packet))
+	copy(fresh, packet)
+
+	return fresh, err
+}
+
+func (t *transport) writePacket(packet []byte) error {
+	if debugTransport {
+		t.printPacket(packet, true)
+	}
+	return t.writer.writePacket(t.bufWriter, t.rand, packet)
+}
+
+func (s *connectionState) writePacket(w *bufio.Writer, rand io.Reader, packet []byte) error {
+	changeKeys := len(packet) > 0 && packet[0] == msgNewKeys
+
+	err := s.packetCipher.writePacket(s.seqNum, w, rand, packet)
+	if err != nil {
+		return err
+	}
+	if err = w.Flush(); err != nil {
+		return err
+	}
+	s.seqNum++
+	if changeKeys {
+		select {
+		case cipher := <-s.pendingKeyChange:
+			s.packetCipher = cipher
+		default:
+			panic("ssh: no key material for msgNewKeys")
+		}
+	}
+	return err
+}
+
+func newTransport(rwc io.ReadWriteCloser, rand io.Reader, isClient bool) *transport {
+	t := &transport{
+		bufReader: bufio.NewReader(rwc),
+		bufWriter: bufio.NewWriter(rwc),
+		rand:      rand,
+		reader: connectionState{
+			packetCipher:     &streamPacketCipher{cipher: noneCipher{}},
+			pendingKeyChange: make(chan packetCipher, 1),
+		},
+		writer: connectionState{
+			packetCipher:     &streamPacketCipher{cipher: noneCipher{}},
+			pendingKeyChange: make(chan packetCipher, 1),
+		},
+		Closer: rwc,
+	}
+	t.isClient = isClient
+
+	if isClient {
+		t.reader.dir = serverKeys
+		t.writer.dir = clientKeys
+	} else {
+		t.reader.dir = clientKeys
+		t.writer.dir = serverKeys
+	}
+
+	return t
+}
+
+type direction struct {
+	ivTag     []byte
+	keyTag    []byte
+	macKeyTag []byte
+}
+
+var (
+	serverKeys = direction{[]byte{'B'}, []byte{'D'}, []byte{'F'}}
+	clientKeys = direction{[]byte{'A'}, []byte{'C'}, []byte{'E'}}
+)
+
+// generateKeys generates key material for IV, MAC and encryption.
+func generateKeys(d direction, algs directionAlgorithms, kex *kexResult) (iv, key, macKey []byte) {
+	cipherMode := cipherModes[algs.Cipher]
+	macMode := macModes[algs.MAC]
+
+	iv = make([]byte, cipherMode.ivSize)
+	key = make([]byte, cipherMode.keySize)
+	macKey = make([]byte, macMode.keySize)
+
+	generateKeyMaterial(iv, d.ivTag, kex)
+	generateKeyMaterial(key, d.keyTag, kex)
+	generateKeyMaterial(macKey, d.macKeyTag, kex)
+	return
+}
+
+// setupKeys sets the cipher and MAC keys from kex.K, kex.H and sessionId, as
+// described in RFC 4253, section 6.4. direction should either be serverKeys
+// (to setup server->client keys) or clientKeys (for client->server keys).
+func newPacketCipher(d direction, algs directionAlgorithms, kex *kexResult) (packetCipher, error) {
+	iv, key, macKey := generateKeys(d, algs, kex)
+
+	if algs.Cipher == gcmCipherID {
+		return newGCMCipher(iv, key)
+	}
+
+	if algs.Cipher == aes128cbcID {
+		return newAESCBCCipher(iv, key, macKey, algs)
+	}
+
+	if algs.Cipher == tripledescbcID {
+		return newTripleDESCBCCipher(iv, key, macKey, algs)
+	}
+
+	c := &streamPacketCipher{
+		mac: macModes[algs.MAC].new(macKey),
+		etm: macModes[algs.MAC].etm,
+	}
+	c.macResult = make([]byte, c.mac.Size())
+
+	var err error
+	c.cipher, err = cipherModes[algs.Cipher].createStream(key, iv)
+	if err != nil {
+		return nil, err
+	}
+
+	return c, nil
+}
+
+// generateKeyMaterial fills out with key material generated from tag, K, H
+// and sessionId, as specified in RFC 4253, section 7.2.
+func generateKeyMaterial(out, tag []byte, r *kexResult) {
+	var digestsSoFar []byte
+
+	h := r.Hash.New()
+	for len(out) > 0 {
+		h.Reset()
+		h.Write(r.K)
+		h.Write(r.H)
+
+		if len(digestsSoFar) == 0 {
+			h.Write(tag)
+			h.Write(r.SessionID)
+		} else {
+			h.Write(digestsSoFar)
+		}
+
+		digest := h.Sum(nil)
+		n := copy(out, digest)
+		out = out[n:]
+		if len(out) > 0 {
+			digestsSoFar = append(digestsSoFar, digest...)
+		}
+	}
+}
+
+const packageVersion = "SSH-2.0-Go"
+
+// Sends and receives a version line.  The versionLine string should
+// be US ASCII, start with "SSH-2.0-", and should not include a
+// newline. exchangeVersions returns the other side's version line.
+func exchangeVersions(rw io.ReadWriter, versionLine []byte) (them []byte, err error) {
+	// Contrary to the RFC, we do not ignore lines that don't
+	// start with "SSH-2.0-" to make the library usable with
+	// nonconforming servers.
+	for _, c := range versionLine {
+		// The spec disallows non US-ASCII chars, and
+		// specifically forbids null chars.
+		if c < 32 {
+			return nil, errors.New("ssh: junk character in version line")
+		}
+	}
+	if _, err = rw.Write(append(versionLine, '\r', '\n')); err != nil {
+		return
+	}
+
+	them, err = readVersion(rw)
+	return them, err
+}
+
+// maxVersionStringBytes is the maximum number of bytes that we'll
+// accept as a version string. RFC 4253 section 4.2 limits this at 255
+// chars
+const maxVersionStringBytes = 255
+
+// Read version string as specified by RFC 4253, section 4.2.
+func readVersion(r io.Reader) ([]byte, error) {
+	versionString := make([]byte, 0, 64)
+	var ok bool
+	var buf [1]byte
+
+	for len(versionString) < maxVersionStringBytes {
+		_, err := io.ReadFull(r, buf[:])
+		if err != nil {
+			return nil, err
+		}
+		// The RFC says that the version should be terminated with \r\n
+		// but several SSH servers actually only send a \n.
+		if buf[0] == '\n' {
+			ok = true
+			break
+		}
+
+		// non ASCII chars are disallowed, but we are lenient,
+		// since Go doesn't use null-terminated strings.
+
+		// The RFC allows a comment after a space, however,
+		// all of it (version and comments) goes into the
+		// session hash.
+		versionString = append(versionString, buf[0])
+	}
+
+	if !ok {
+		return nil, errors.New("ssh: overflow reading version string")
+	}
+
+	// There might be a '\r' on the end which we should remove.
+	if len(versionString) > 0 && versionString[len(versionString)-1] == '\r' {
+		versionString = versionString[:len(versionString)-1]
+	}
+	return versionString, nil
+}

vendor/golang.org/x/sys/.gitattributes

@@ -0,0 +1,10 @@
+# Treat all files in this repo as binary, with no git magic updating
+# line endings. Windows users contributing to Go will need to use a
+# modern version of git and editors capable of LF line endings.
+#
+# We'll prevent accidental CRLF line endings from entering the repo
+# via the git-review gofmt checks.
+#
+# See golang.org/issue/9281
+
+* -text

vendor/golang.org/x/sys/.gitignore

@@ -0,0 +1,2 @@
+# Add no patterns to .hgignore except for files generated by the build.
+last-change

vendor/golang.org/x/sys/AUTHORS

@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at http://tip.golang.org/AUTHORS.

vendor/golang.org/x/sys/CONTRIBUTING.md

@@ -0,0 +1,31 @@
+# Contributing to Go
+
+Go is an open source project.
+
+It is the work of hundreds of contributors. We appreciate your help!
+
+
+## Filing issues
+
+When [filing an issue](https://golang.org/issue/new), make sure to answer these five questions:
+
+1. What version of Go are you using (`go version`)?
+2. What operating system and processor architecture are you using?
+3. What did you do?
+4. What did you expect to see?
+5. What did you see instead?
+
+General questions should go to the [golang-nuts mailing list](https://groups.google.com/group/golang-nuts) instead of the issue tracker.
+The gophers there will answer or ask you to file an issue if you've tripped over a bug.
+
+## Contributing code
+
+Please read the [Contribution Guidelines](https://golang.org/doc/contribute.html)
+before sending patches.
+
+**We do not accept GitHub pull requests**
+(we use [Gerrit](https://code.google.com/p/gerrit/) instead for code review).
+
+Unless otherwise noted, the Go source files are distributed under
+the BSD-style license found in the LICENSE file.
+

vendor/golang.org/x/sys/CONTRIBUTORS

@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at http://tip.golang.org/CONTRIBUTORS.

vendor/golang.org/x/sys/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/golang.org/x/sys/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/golang.org/x/sys/README.md

@@ -0,0 +1,18 @@
+# sys
+
+This repository holds supplemental Go packages for low-level interactions with
+the operating system.
+
+## Download/Install
+
+The easiest way to install is to run `go get -u golang.org/x/sys`. You can
+also manually git clone the repository to `$GOPATH/src/golang.org/x/sys`.
+
+## Report Issues / Send Patches
+
+This repository uses Gerrit for code changes. To learn how to submit changes to
+this repository, see https://golang.org/doc/contribute.html.
+
+The main issue tracker for the sys repository is located at
+https://github.com/golang/go/issues. Prefix your issue with "x/sys:" in the
+subject line, so it is easy to find.

vendor/golang.org/x/sys/codereview.cfg

@@ -0,0 +1 @@
+issuerepo: golang/go

vendor/golang.org/x/sys/unix/.gitignore

@@ -0,0 +1 @@
+_obj/

vendor/golang.org/x/sys/unix/README.md

@@ -0,0 +1,173 @@
+# Building `sys/unix`
+
+The sys/unix package provides access to the raw system call interface of the
+underlying operating system. See: https://godoc.org/golang.org/x/sys/unix
+
+Porting Go to a new architecture/OS combination or adding syscalls, types, or
+constants to an existing architecture/OS pair requires some manual effort;
+however, there are tools that automate much of the process.
+
+## Build Systems
+
+There are currently two ways we generate the necessary files. We are currently
+migrating the build system to use containers so the builds are reproducible.
+This is being done on an OS-by-OS basis. Please update this documentation as
+components of the build system change.
+
+### Old Build System (currently for `GOOS != "Linux" || GOARCH == "sparc64"`)
+
+The old build system generates the Go files based on the C header files
+present on your system. This means that files
+for a given GOOS/GOARCH pair must be generated on a system with that OS and
+architecture. This also means that the generated code can differ from system
+to system, based on differences in the header files.
+
+To avoid this, if you are using the old build system, only generate the Go
+files on an installation with unmodified header files. It is also important to
+keep track of which version of the OS the files were generated from (ex.
+Darwin 14 vs Darwin 15). This makes it easier to track the progress of changes
+and have each OS upgrade correspond to a single change.
+
+To build the files for your current OS and architecture, make sure GOOS and
+GOARCH are set correctly and run `mkall.sh`. This will generate the files for
+your specific system. Running `mkall.sh -n` shows the commands that will be run.
+
+Requirements: bash, perl, go
+
+### New Build System (currently for `GOOS == "Linux" && GOARCH != "sparc64"`)
+
+The new build system uses a Docker container to generate the go files directly
+from source checkouts of the kernel and various system libraries. This means
+that on any platform that supports Docker, all the files using the new build
+system can be generated at once, and generated files will not change based on
+what the person running the scripts has installed on their computer.
+
+The OS specific files for the new build system are located in the `${GOOS}`
+directory, and the build is coordinated by the `${GOOS}/mkall.go` program. When
+the kernel or system library updates, modify the Dockerfile at
+`${GOOS}/Dockerfile` to checkout the new release of the source.
+
+To build all the files under the new build system, you must be on an amd64/Linux
+system and have your GOOS and GOARCH set accordingly. Running `mkall.sh` will
+then generate all of the files for all of the GOOS/GOARCH pairs in the new build
+system. Running `mkall.sh -n` shows the commands that will be run.
+
+Requirements: bash, perl, go, docker
+
+## Component files
+
+This section describes the various files used in the code generation process.
+It also contains instructions on how to modify these files to add a new
+architecture/OS or to add additional syscalls, types, or constants. Note that
+if you are using the new build system, the scripts cannot be called normally.
+They must be called from within the docker container.
+
+### asm files
+
+The hand-written assembly file at `asm_${GOOS}_${GOARCH}.s` implements system
+call dispatch. There are three entry points:
+```
+  func Syscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
+  func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+  func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
+```
+The first and second are the standard ones; they differ only in how many
+arguments can be passed to the kernel. The third is for low-level use by the
+ForkExec wrapper. Unlike the first two, it does not call into the scheduler to
+let it know that a system call is running.
+
+When porting Go to an new architecture/OS, this file must be implemented for
+each GOOS/GOARCH pair.
+
+### mksysnum
+
+Mksysnum is a script located at `${GOOS}/mksysnum.pl` (or `mksysnum_${GOOS}.pl`
+for the old system). This script takes in a list of header files containing the
+syscall number declarations and parses them to produce the corresponding list of
+Go numeric constants. See `zsysnum_${GOOS}_${GOARCH}.go` for the generated
+constants.
+
+Adding new syscall numbers is mostly done by running the build on a sufficiently
+new installation of the target OS (or updating the source checkouts for the
+new build system). However, depending on the OS, you make need to update the
+parsing in mksysnum.
+
+### mksyscall.pl
+
+The `syscall.go`, `syscall_${GOOS}.go`, `syscall_${GOOS}_${GOARCH}.go` are
+hand-written Go files which implement system calls (for unix, the specific OS,
+or the specific OS/Architecture pair respectively) that need special handling
+and list `//sys` comments giving prototypes for ones that can be generated.
+
+The mksyscall.pl script takes the `//sys` and `//sysnb` comments and converts
+them into syscalls. This requires the name of the prototype in the comment to
+match a syscall number in the `zsysnum_${GOOS}_${GOARCH}.go` file. The function
+prototype can be exported (capitalized) or not.
+
+Adding a new syscall often just requires adding a new `//sys` function prototype
+with the desired arguments and a capitalized name so it is exported. However, if
+you want the interface to the syscall to be different, often one will make an
+unexported `//sys` prototype, an then write a custom wrapper in
+`syscall_${GOOS}.go`.
+
+### types files
+
+For each OS, there is a hand-written Go file at `${GOOS}/types.go` (or
+`types_${GOOS}.go` on the old system). This file includes standard C headers and
+creates Go type aliases to the corresponding C types. The file is then fed
+through godef to get the Go compatible definitions. Finally, the generated code
+is fed though mkpost.go to format the code correctly and remove any hidden or
+private identifiers. This cleaned-up code is written to
+`ztypes_${GOOS}_${GOARCH}.go`.
+
+The hardest part about preparing this file is figuring out which headers to
+include and which symbols need to be `#define`d to get the actual data
+structures that pass through to the kernel system calls. Some C libraries
+preset alternate versions for binary compatibility and translate them on the
+way in and out of system calls, but there is almost always a `#define` that can
+get the real ones.
+See `types_darwin.go` and `linux/types.go` for examples.
+
+To add a new type, add in the necessary include statement at the top of the
+file (if it is not already there) and add in a type alias line. Note that if
+your type is significantly different on different architectures, you may need
+some `#if/#elif` macros in your include statements.
+
+### mkerrors.sh
+
+This script is used to generate the system's various constants. This doesn't
+just include the error numbers and error strings, but also the signal numbers
+an a wide variety of miscellaneous constants. The constants come from the list
+of include files in the `includes_${uname}` variable. A regex then picks out
+the desired `#define` statements, and generates the corresponding Go constants.
+The error numbers and strings are generated from `#include <errno.h>`, and the
+signal numbers and strings are generated from `#include <signal.h>`. All of
+these constants are written to `zerrors_${GOOS}_${GOARCH}.go` via a C program,
+`_errors.c`, which prints out all the constants.
+
+To add a constant, add the header that includes it to the appropriate variable.
+Then, edit the regex (if necessary) to match the desired constant. Avoid making
+the regex too broad to avoid matching unintended constants.
+
+
+## Generated files
+
+### `zerror_${GOOS}_${GOARCH}.go`
+
+A file containing all of the system's generated error numbers, error strings,
+signal numbers, and constants. Generated by `mkerrors.sh` (see above).
+
+### `zsyscall_${GOOS}_${GOARCH}.go`
+
+A file containing all the generated syscalls for a specific GOOS and GOARCH.
+Generated by `mksyscall.pl` (see above).
+
+### `zsysnum_${GOOS}_${GOARCH}.go`
+
+A list of numeric constants for all the syscall number of the specific GOOS
+and GOARCH. Generated by mksysnum (see above).
+
+### `ztypes_${GOOS}_${GOARCH}.go`
+
+A file containing Go types for passing into (or returning from) syscalls.
+Generated by godefs and the types file (see above).

vendor/golang.org/x/sys/unix/asm_darwin_386.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for 386, Darwin
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	JMP	syscall·Syscall9(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_darwin_amd64.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for AMD64, Darwin
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	JMP	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_darwin_arm.s

@@ -0,0 +1,30 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+// +build arm,darwin
+
+#include "textflag.h"
+
+//
+// System call support for ARM, Darwin
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	B	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	B	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-28
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	B	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_darwin_arm64.s

@@ -0,0 +1,30 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+// +build arm64,darwin
+
+#include "textflag.h"
+
+//
+// System call support for AMD64, Darwin
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	B	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	B	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-56
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	B	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_dragonfly_amd64.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for AMD64, DragonFly
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-64
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-88
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-112
+	JMP	syscall·Syscall9(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-64
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-88
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_freebsd_386.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for 386, FreeBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	JMP	syscall·Syscall9(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_freebsd_amd64.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for AMD64, FreeBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	JMP	syscall·Syscall9(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_freebsd_arm.s

@@ -0,0 +1,29 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for ARM, FreeBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	B	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	B	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-28
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	B	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_linux_386.s

@@ -0,0 +1,35 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for 386, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·socketcall(SB),NOSPLIT,$0-36
+	JMP	syscall·socketcall(SB)
+
+TEXT ·rawsocketcall(SB),NOSPLIT,$0-36
+	JMP	syscall·rawsocketcall(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-28
+	JMP	syscall·seek(SB)

vendor/golang.org/x/sys/unix/asm_linux_amd64.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for AMD64, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	JMP	syscall·Syscall(SB)
+
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·gettimeofday(SB),NOSPLIT,$0-16
+	JMP	syscall·gettimeofday(SB)

vendor/golang.org/x/sys/unix/asm_linux_arm.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for arm, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	B	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	B	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-32
+	B	syscall·seek(SB)

vendor/golang.org/x/sys/unix/asm_linux_arm64.s

@@ -0,0 +1,24 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+// +build arm64
+// +build !gccgo
+
+#include "textflag.h"
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	B	syscall·Syscall(SB)
+
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+	B	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	B	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-80
+	B	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_linux_mips64x.s

@@ -0,0 +1,28 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+// +build mips64 mips64le
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for mips64, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_linux_mipsx.s

@@ -0,0 +1,31 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+// +build mips mipsle
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for mips, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JMP syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	JMP syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	JMP syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-28
+	JMP syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_linux_ppc64x.s

@@ -0,0 +1,28 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+// +build ppc64 ppc64le
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for ppc64, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	BR	syscall·Syscall(SB)
+
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+	BR	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	BR	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-80
+	BR	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_linux_s390x.s

@@ -0,0 +1,28 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build s390x
+// +build linux
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for s390x, Linux
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT ·Syscall(SB),NOSPLIT,$0-56
+	BR	syscall·Syscall(SB)
+
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+	BR	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	BR	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-80
+	BR	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_netbsd_386.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for 386, NetBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	JMP	syscall·Syscall9(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_netbsd_amd64.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for AMD64, NetBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	JMP	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_netbsd_arm.s

@@ -0,0 +1,29 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for ARM, NetBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	B	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	B	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-28
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	B	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_openbsd_386.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for 386, OpenBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	JMP	syscall·Syscall9(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_openbsd_amd64.s

@@ -0,0 +1,29 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for AMD64, OpenBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	JMP	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_openbsd_arm.s

@@ -0,0 +1,29 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for ARM, OpenBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-28
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-40
+	B	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-52
+	B	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-28
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+	B	syscall·RawSyscall6(SB)

vendor/golang.org/x/sys/unix/asm_solaris_amd64.s

@@ -0,0 +1,17 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System calls for amd64, Solaris are implemented in runtime/syscall_solaris.go
+//
+
+TEXT ·sysvicall6(SB),NOSPLIT,$0-88
+	JMP	syscall·sysvicall6(SB)
+
+TEXT ·rawSysvicall6(SB),NOSPLIT,$0-88
+	JMP	syscall·rawSysvicall6(SB)

vendor/golang.org/x/sys/unix/bluetooth_linux.go

@@ -0,0 +1,35 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Bluetooth sockets and messages
+
+package unix
+
+// Bluetooth Protocols
+const (
+	BTPROTO_L2CAP  = 0
+	BTPROTO_HCI    = 1
+	BTPROTO_SCO    = 2
+	BTPROTO_RFCOMM = 3
+	BTPROTO_BNEP   = 4
+	BTPROTO_CMTP   = 5
+	BTPROTO_HIDP   = 6
+	BTPROTO_AVDTP  = 7
+)
+
+const (
+	HCI_CHANNEL_RAW     = 0
+	HCI_CHANNEL_USER    = 1
+	HCI_CHANNEL_MONITOR = 2
+	HCI_CHANNEL_CONTROL = 3
+)
+
+// Socketoption Level
+const (
+	SOL_BLUETOOTH = 0x112
+	SOL_HCI       = 0x0
+	SOL_L2CAP     = 0x6
+	SOL_RFCOMM    = 0x12
+	SOL_SCO       = 0x11
+)

vendor/golang.org/x/sys/unix/cap_freebsd.go

@@ -0,0 +1,195 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build freebsd
+
+package unix
+
+import (
+	errorspkg "errors"
+	"fmt"
+)
+
+// Go implementation of C mostly found in /usr/src/sys/kern/subr_capability.c
+
+const (
+	// This is the version of CapRights this package understands. See C implementation for parallels.
+	capRightsGoVersion = CAP_RIGHTS_VERSION_00
+	capArSizeMin       = CAP_RIGHTS_VERSION_00 + 2
+	capArSizeMax       = capRightsGoVersion + 2
+)
+
+var (
+	bit2idx = []int{
+		-1, 0, 1, -1, 2, -1, -1, -1, 3, -1, -1, -1, -1, -1, -1, -1,
+		4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+	}
+)
+
+func capidxbit(right uint64) int {
+	return int((right >> 57) & 0x1f)
+}
+
+func rightToIndex(right uint64) (int, error) {
+	idx := capidxbit(right)
+	if idx < 0 || idx >= len(bit2idx) {
+		return -2, fmt.Errorf("index for right 0x%x out of range", right)
+	}
+	return bit2idx[idx], nil
+}
+
+func caprver(right uint64) int {
+	return int(right >> 62)
+}
+
+func capver(rights *CapRights) int {
+	return caprver(rights.Rights[0])
+}
+
+func caparsize(rights *CapRights) int {
+	return capver(rights) + 2
+}
+
+// CapRightsSet sets the permissions in setrights in rights.
+func CapRightsSet(rights *CapRights, setrights []uint64) error {
+	// This is essentially a copy of cap_rights_vset()
+	if capver(rights) != CAP_RIGHTS_VERSION_00 {
+		return fmt.Errorf("bad rights version %d", capver(rights))
+	}
+
+	n := caparsize(rights)
+	if n < capArSizeMin || n > capArSizeMax {
+		return errorspkg.New("bad rights size")
+	}
+
+	for _, right := range setrights {
+		if caprver(right) != CAP_RIGHTS_VERSION_00 {
+			return errorspkg.New("bad right version")
+		}
+		i, err := rightToIndex(right)
+		if err != nil {
+			return err
+		}
+		if i >= n {
+			return errorspkg.New("index overflow")
+		}
+		if capidxbit(rights.Rights[i]) != capidxbit(right) {
+			return errorspkg.New("index mismatch")
+		}
+		rights.Rights[i] |= right
+		if capidxbit(rights.Rights[i]) != capidxbit(right) {
+			return errorspkg.New("index mismatch (after assign)")
+		}
+	}
+
+	return nil
+}
+
+// CapRightsClear clears the permissions in clearrights from rights.
+func CapRightsClear(rights *CapRights, clearrights []uint64) error {
+	// This is essentially a copy of cap_rights_vclear()
+	if capver(rights) != CAP_RIGHTS_VERSION_00 {
+		return fmt.Errorf("bad rights version %d", capver(rights))
+	}
+
+	n := caparsize(rights)
+	if n < capArSizeMin || n > capArSizeMax {
+		return errorspkg.New("bad rights size")
+	}
+
+	for _, right := range clearrights {
+		if caprver(right) != CAP_RIGHTS_VERSION_00 {
+			return errorspkg.New("bad right version")
+		}
+		i, err := rightToIndex(right)
+		if err != nil {
+			return err
+		}
+		if i >= n {
+			return errorspkg.New("index overflow")
+		}
+		if capidxbit(rights.Rights[i]) != capidxbit(right) {
+			return errorspkg.New("index mismatch")
+		}
+		rights.Rights[i] &= ^(right & 0x01FFFFFFFFFFFFFF)
+		if capidxbit(rights.Rights[i]) != capidxbit(right) {
+			return errorspkg.New("index mismatch (after assign)")
+		}
+	}
+
+	return nil
+}
+
+// CapRightsIsSet checks whether all the permissions in setrights are present in rights.
+func CapRightsIsSet(rights *CapRights, setrights []uint64) (bool, error) {
+	// This is essentially a copy of cap_rights_is_vset()
+	if capver(rights) != CAP_RIGHTS_VERSION_00 {
+		return false, fmt.Errorf("bad rights version %d", capver(rights))
+	}
+
+	n := caparsize(rights)
+	if n < capArSizeMin || n > capArSizeMax {
+		return false, errorspkg.New("bad rights size")
+	}
+
+	for _, right := range setrights {
+		if caprver(right) != CAP_RIGHTS_VERSION_00 {
+			return false, errorspkg.New("bad right version")
+		}
+		i, err := rightToIndex(right)
+		if err != nil {
+			return false, err
+		}
+		if i >= n {
+			return false, errorspkg.New("index overflow")
+		}
+		if capidxbit(rights.Rights[i]) != capidxbit(right) {
+			return false, errorspkg.New("index mismatch")
+		}
+		if (rights.Rights[i] & right) != right {
+			return false, nil
+		}
+	}
+
+	return true, nil
+}
+
+func capright(idx uint64, bit uint64) uint64 {
+	return ((1 << (57 + idx)) | bit)
+}
+
+// CapRightsInit returns a pointer to an initialised CapRights structure filled with rights.
+// See man cap_rights_init(3) and rights(4).
+func CapRightsInit(rights []uint64) (*CapRights, error) {
+	var r CapRights
+	r.Rights[0] = (capRightsGoVersion << 62) | capright(0, 0)
+	r.Rights[1] = capright(1, 0)
+
+	err := CapRightsSet(&r, rights)
+	if err != nil {
+		return nil, err
+	}
+	return &r, nil
+}
+
+// CapRightsLimit reduces the operations permitted on fd to at most those contained in rights.
+// The capability rights on fd can never be increased by CapRightsLimit.
+// See man cap_rights_limit(2) and rights(4).
+func CapRightsLimit(fd uintptr, rights *CapRights) error {
+	return capRightsLimit(int(fd), rights)
+}
+
+// CapRightsGet returns a CapRights structure containing the operations permitted on fd.
+// See man cap_rights_get(3) and rights(4).
+func CapRightsGet(fd uintptr) (*CapRights, error) {
+	r, err := CapRightsInit(nil)
+	if err != nil {
+		return nil, err
+	}
+	err = capRightsGet(capRightsGoVersion, int(fd), r)
+	if err != nil {
+		return nil, err
+	}
+	return r, nil
+}

vendor/golang.org/x/sys/unix/constants.go

@@ -0,0 +1,13 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package unix
+
+const (
+	R_OK = 0x4
+	W_OK = 0x2
+	X_OK = 0x1
+)

vendor/golang.org/x/sys/unix/dev_darwin.go

@@ -0,0 +1,24 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions to access/create device major and minor numbers matching the
+// encoding used in Darwin's sys/types.h header.
+
+package unix
+
+// Major returns the major component of a Darwin device number.
+func Major(dev uint64) uint32 {
+	return uint32((dev >> 24) & 0xff)
+}
+
+// Minor returns the minor component of a Darwin device number.
+func Minor(dev uint64) uint32 {
+	return uint32(dev & 0xffffff)
+}
+
+// Mkdev returns a Darwin device number generated from the given major and minor
+// components.
+func Mkdev(major, minor uint32) uint64 {
+	return (uint64(major) << 24) | uint64(minor)
+}

vendor/golang.org/x/sys/unix/dev_dragonfly.go

@@ -0,0 +1,30 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions to access/create device major and minor numbers matching the
+// encoding used in Dragonfly's sys/types.h header.
+//
+// The information below is extracted and adapted from sys/types.h:
+//
+// Minor gives a cookie instead of an index since in order to avoid changing the
+// meanings of bits 0-15 or wasting time and space shifting bits 16-31 for
+// devices that don't use them.
+
+package unix
+
+// Major returns the major component of a DragonFlyBSD device number.
+func Major(dev uint64) uint32 {
+	return uint32((dev >> 8) & 0xff)
+}
+
+// Minor returns the minor component of a DragonFlyBSD device number.
+func Minor(dev uint64) uint32 {
+	return uint32(dev & 0xffff00ff)
+}
+
+// Mkdev returns a DragonFlyBSD device number generated from the given major and
+// minor components.
+func Mkdev(major, minor uint32) uint64 {
+	return (uint64(major) << 8) | uint64(minor)
+}

vendor/golang.org/x/sys/unix/dev_freebsd.go

@@ -0,0 +1,30 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions to access/create device major and minor numbers matching the
+// encoding used in FreeBSD's sys/types.h header.
+//
+// The information below is extracted and adapted from sys/types.h:
+//
+// Minor gives a cookie instead of an index since in order to avoid changing the
+// meanings of bits 0-15 or wasting time and space shifting bits 16-31 for
+// devices that don't use them.
+
+package unix
+
+// Major returns the major component of a FreeBSD device number.
+func Major(dev uint64) uint32 {
+	return uint32((dev >> 8) & 0xff)
+}
+
+// Minor returns the minor component of a FreeBSD device number.
+func Minor(dev uint64) uint32 {
+	return uint32(dev & 0xffff00ff)
+}
+
+// Mkdev returns a FreeBSD device number generated from the given major and
+// minor components.
+func Mkdev(major, minor uint32) uint64 {
+	return (uint64(major) << 8) | uint64(minor)
+}

vendor/golang.org/x/sys/unix/dev_linux.go

@@ -0,0 +1,42 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions to access/create device major and minor numbers matching the
+// encoding used by the Linux kernel and glibc.
+//
+// The information below is extracted and adapted from bits/sysmacros.h in the
+// glibc sources:
+//
+// dev_t in glibc is 64-bit, with 32-bit major and minor numbers. glibc's
+// default encoding is MMMM Mmmm mmmM MMmm, where M is a hex digit of the major
+// number and m is a hex digit of the minor number. This is backward compatible
+// with legacy systems where dev_t is 16 bits wide, encoded as MMmm. It is also
+// backward compatible with the Linux kernel, which for some architectures uses
+// 32-bit dev_t, encoded as mmmM MMmm.
+
+package unix
+
+// Major returns the major component of a Linux device number.
+func Major(dev uint64) uint32 {
+	major := uint32((dev & 0x00000000000fff00) >> 8)
+	major |= uint32((dev & 0xfffff00000000000) >> 32)
+	return major
+}
+
+// Minor returns the minor component of a Linux device number.
+func Minor(dev uint64) uint32 {
+	minor := uint32((dev & 0x00000000000000ff) >> 0)
+	minor |= uint32((dev & 0x00000ffffff00000) >> 12)
+	return minor
+}
+
+// Mkdev returns a Linux device number generated from the given major and minor
+// components.
+func Mkdev(major, minor uint32) uint64 {
+	dev := (uint64(major) & 0x00000fff) << 8
+	dev |= (uint64(major) & 0xfffff000) << 32
+	dev |= (uint64(minor) & 0x000000ff) << 0
+	dev |= (uint64(minor) & 0xffffff00) << 12
+	return dev
+}

vendor/golang.org/x/sys/unix/dev_netbsd.go

@@ -0,0 +1,29 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions to access/create device major and minor numbers matching the
+// encoding used in NetBSD's sys/types.h header.
+
+package unix
+
+// Major returns the major component of a NetBSD device number.
+func Major(dev uint64) uint32 {
+	return uint32((dev & 0x000fff00) >> 8)
+}
+
+// Minor returns the minor component of a NetBSD device number.
+func Minor(dev uint64) uint32 {
+	minor := uint32((dev & 0x000000ff) >> 0)
+	minor |= uint32((dev & 0xfff00000) >> 12)
+	return minor
+}
+
+// Mkdev returns a NetBSD device number generated from the given major and minor
+// components.
+func Mkdev(major, minor uint32) uint64 {
+	dev := (uint64(major) << 8) & 0x000fff00
+	dev |= (uint64(minor) << 12) & 0xfff00000
+	dev |= (uint64(minor) << 0) & 0x000000ff
+	return dev
+}

vendor/golang.org/x/sys/unix/dev_openbsd.go

@@ -0,0 +1,29 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions to access/create device major and minor numbers matching the
+// encoding used in OpenBSD's sys/types.h header.
+
+package unix
+
+// Major returns the major component of an OpenBSD device number.
+func Major(dev uint64) uint32 {
+	return uint32((dev & 0x0000ff00) >> 8)
+}
+
+// Minor returns the minor component of an OpenBSD device number.
+func Minor(dev uint64) uint32 {
+	minor := uint32((dev & 0x000000ff) >> 0)
+	minor |= uint32((dev & 0xffff0000) >> 8)
+	return minor
+}
+
+// Mkdev returns an OpenBSD device number generated from the given major and minor
+// components.
+func Mkdev(major, minor uint32) uint64 {
+	dev := (uint64(major) << 8) & 0x0000ff00
+	dev |= (uint64(minor) << 8) & 0xffff0000
+	dev |= (uint64(minor) << 0) & 0x000000ff
+	return dev
+}

vendor/golang.org/x/sys/unix/dirent.go

@@ -0,0 +1,102 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+package unix
+
+import "unsafe"
+
+// readInt returns the size-bytes unsigned integer in native byte order at offset off.
+func readInt(b []byte, off, size uintptr) (u uint64, ok bool) {
+	if len(b) < int(off+size) {
+		return 0, false
+	}
+	if isBigEndian {
+		return readIntBE(b[off:], size), true
+	}
+	return readIntLE(b[off:], size), true
+}
+
+func readIntBE(b []byte, size uintptr) uint64 {
+	switch size {
+	case 1:
+		return uint64(b[0])
+	case 2:
+		_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[1]) | uint64(b[0])<<8
+	case 4:
+		_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[3]) | uint64(b[2])<<8 | uint64(b[1])<<16 | uint64(b[0])<<24
+	case 8:
+		_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+			uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
+	default:
+		panic("syscall: readInt with unsupported size")
+	}
+}
+
+func readIntLE(b []byte, size uintptr) uint64 {
+	switch size {
+	case 1:
+		return uint64(b[0])
+	case 2:
+		_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[0]) | uint64(b[1])<<8
+	case 4:
+		_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24
+	case 8:
+		_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
+		return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+			uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	default:
+		panic("syscall: readInt with unsupported size")
+	}
+}
+
+// ParseDirent parses up to max directory entries in buf,
+// appending the names to names. It returns the number of
+// bytes consumed from buf, the number of entries added
+// to names, and the new names slice.
+func ParseDirent(buf []byte, max int, names []string) (consumed int, count int, newnames []string) {
+	origlen := len(buf)
+	count = 0
+	for max != 0 && len(buf) > 0 {
+		reclen, ok := direntReclen(buf)
+		if !ok || reclen > uint64(len(buf)) {
+			return origlen, count, names
+		}
+		rec := buf[:reclen]
+		buf = buf[reclen:]
+		ino, ok := direntIno(rec)
+		if !ok {
+			break
+		}
+		if ino == 0 { // File absent in directory.
+			continue
+		}
+		const namoff = uint64(unsafe.Offsetof(Dirent{}.Name))
+		namlen, ok := direntNamlen(rec)
+		if !ok || namoff+namlen > uint64(len(rec)) {
+			break
+		}
+		name := rec[namoff : namoff+namlen]
+		for i, c := range name {
+			if c == 0 {
+				name = name[:i]
+				break
+			}
+		}
+		// Check for useless names before allocating a string.
+		if string(name) == "." || string(name) == ".." {
+			continue
+		}
+		max--
+		count++
+		names = append(names, string(name))
+	}
+	return origlen - len(buf), count, names
+}

vendor/golang.org/x/sys/unix/endian_big.go

@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// +build ppc64 s390x mips mips64
+
+package unix
+
+const isBigEndian = true

vendor/golang.org/x/sys/unix/endian_little.go

@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// +build 386 amd64 amd64p32 arm arm64 ppc64le mipsle mips64le
+
+package unix
+
+const isBigEndian = false

vendor/golang.org/x/sys/unix/env_unix.go

@@ -0,0 +1,27 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+// Unix environment variables.
+
+package unix
+
+import "syscall"
+
+func Getenv(key string) (value string, found bool) {
+	return syscall.Getenv(key)
+}
+
+func Setenv(key, value string) error {
+	return syscall.Setenv(key, value)
+}
+
+func Clearenv() {
+	syscall.Clearenv()
+}
+
+func Environ() []string {
+	return syscall.Environ()
+}

vendor/golang.org/x/sys/unix/env_unset.go

@@ -0,0 +1,14 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.4
+
+package unix
+
+import "syscall"
+
+func Unsetenv(key string) error {
+	// This was added in Go 1.4.
+	return syscall.Unsetenv(key)
+}

vendor/golang.org/x/sys/unix/errors_freebsd_386.go

@@ -0,0 +1,227 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Constants that were deprecated or moved to enums in the FreeBSD headers. Keep
+// them here for backwards compatibility.
+
+package unix
+
+const (
+	IFF_SMART                         = 0x20
+	IFT_1822                          = 0x2
+	IFT_A12MPPSWITCH                  = 0x82
+	IFT_AAL2                          = 0xbb
+	IFT_AAL5                          = 0x31
+	IFT_ADSL                          = 0x5e
+	IFT_AFLANE8023                    = 0x3b
+	IFT_AFLANE8025                    = 0x3c
+	IFT_ARAP                          = 0x58
+	IFT_ARCNET                        = 0x23
+	IFT_ARCNETPLUS                    = 0x24
+	IFT_ASYNC                         = 0x54
+	IFT_ATM                           = 0x25
+	IFT_ATMDXI                        = 0x69
+	IFT_ATMFUNI                       = 0x6a
+	IFT_ATMIMA                        = 0x6b
+	IFT_ATMLOGICAL                    = 0x50
+	IFT_ATMRADIO                      = 0xbd
+	IFT_ATMSUBINTERFACE               = 0x86
+	IFT_ATMVCIENDPT                   = 0xc2
+	IFT_ATMVIRTUAL                    = 0x95
+	IFT_BGPPOLICYACCOUNTING           = 0xa2
+	IFT_BSC                           = 0x53
+	IFT_CCTEMUL                       = 0x3d
+	IFT_CEPT                          = 0x13
+	IFT_CES                           = 0x85
+	IFT_CHANNEL                       = 0x46
+	IFT_CNR                           = 0x55
+	IFT_COFFEE                        = 0x84
+	IFT_COMPOSITELINK                 = 0x9b
+	IFT_DCN                           = 0x8d
+	IFT_DIGITALPOWERLINE              = 0x8a
+	IFT_DIGITALWRAPPEROVERHEADCHANNEL = 0xba
+	IFT_DLSW                          = 0x4a
+	IFT_DOCSCABLEDOWNSTREAM           = 0x80
+	IFT_DOCSCABLEMACLAYER             = 0x7f
+	IFT_DOCSCABLEUPSTREAM             = 0x81
+	IFT_DS0                           = 0x51
+	IFT_DS0BUNDLE                     = 0x52
+	IFT_DS1FDL                        = 0xaa
+	IFT_DS3                           = 0x1e
+	IFT_DTM                           = 0x8c
+	IFT_DVBASILN                      = 0xac
+	IFT_DVBASIOUT                     = 0xad
+	IFT_DVBRCCDOWNSTREAM              = 0x93
+	IFT_DVBRCCMACLAYER                = 0x92
+	IFT_DVBRCCUPSTREAM                = 0x94
+	IFT_ENC                           = 0xf4
+	IFT_EON                           = 0x19
+	IFT_EPLRS                         = 0x57
+	IFT_ESCON                         = 0x49
+	IFT_ETHER                         = 0x6
+	IFT_FAITH                         = 0xf2
+	IFT_FAST                          = 0x7d
+	IFT_FASTETHER                     = 0x3e
+	IFT_FASTETHERFX                   = 0x45
+	IFT_FDDI                          = 0xf
+	IFT_FIBRECHANNEL                  = 0x38
+	IFT_FRAMERELAYINTERCONNECT        = 0x3a
+	IFT_FRAMERELAYMPI                 = 0x5c
+	IFT_FRDLCIENDPT                   = 0xc1
+	IFT_FRELAY                        = 0x20
+	IFT_FRELAYDCE                     = 0x2c
+	IFT_FRF16MFRBUNDLE                = 0xa3
+	IFT_FRFORWARD                     = 0x9e
+	IFT_G703AT2MB                     = 0x43
+	IFT_G703AT64K                     = 0x42
+	IFT_GIF                           = 0xf0
+	IFT_GIGABITETHERNET               = 0x75
+	IFT_GR303IDT                      = 0xb2
+	IFT_GR303RDT                      = 0xb1
+	IFT_H323GATEKEEPER                = 0xa4
+	IFT_H323PROXY                     = 0xa5
+	IFT_HDH1822                       = 0x3
+	IFT_HDLC                          = 0x76
+	IFT_HDSL2                         = 0xa8
+	IFT_HIPERLAN2                     = 0xb7
+	IFT_HIPPI                         = 0x2f
+	IFT_HIPPIINTERFACE                = 0x39
+	IFT_HOSTPAD                       = 0x5a
+	IFT_HSSI                          = 0x2e
+	IFT_HY                            = 0xe
+	IFT_IBM370PARCHAN                 = 0x48
+	IFT_IDSL                          = 0x9a
+	IFT_IEEE80211                     = 0x47
+	IFT_IEEE80212                     = 0x37
+	IFT_IEEE8023ADLAG                 = 0xa1
+	IFT_IFGSN                         = 0x91
+	IFT_IMT                           = 0xbe
+	IFT_INTERLEAVE                    = 0x7c
+	IFT_IP                            = 0x7e
+	IFT_IPFORWARD                     = 0x8e
+	IFT_IPOVERATM                     = 0x72
+	IFT_IPOVERCDLC                    = 0x6d
+	IFT_IPOVERCLAW                    = 0x6e
+	IFT_IPSWITCH                      = 0x4e
+	IFT_IPXIP                         = 0xf9
+	IFT_ISDN                          = 0x3f
+	IFT_ISDNBASIC                     = 0x14
+	IFT_ISDNPRIMARY                   = 0x15
+	IFT_ISDNS                         = 0x4b
+	IFT_ISDNU                         = 0x4c
+	IFT_ISO88022LLC                   = 0x29
+	IFT_ISO88023                      = 0x7
+	IFT_ISO88024                      = 0x8
+	IFT_ISO88025                      = 0x9
+	IFT_ISO88025CRFPINT               = 0x62
+	IFT_ISO88025DTR                   = 0x56
+	IFT_ISO88025FIBER                 = 0x73
+	IFT_ISO88026                      = 0xa
+	IFT_ISUP                          = 0xb3
+	IFT_L3IPXVLAN                     = 0x89
+	IFT_LAPB                          = 0x10
+	IFT_LAPD                          = 0x4d
+	IFT_LAPF                          = 0x77
+	IFT_LOCALTALK                     = 0x2a
+	IFT_LOOP                          = 0x18
+	IFT_MEDIAMAILOVERIP               = 0x8b
+	IFT_MFSIGLINK                     = 0xa7
+	IFT_MIOX25                        = 0x26
+	IFT_MODEM                         = 0x30
+	IFT_MPC                           = 0x71
+	IFT_MPLS                          = 0xa6
+	IFT_MPLSTUNNEL                    = 0x96
+	IFT_MSDSL                         = 0x8f
+	IFT_MVL                           = 0xbf
+	IFT_MYRINET                       = 0x63
+	IFT_NFAS                          = 0xaf
+	IFT_NSIP                          = 0x1b
+	IFT_OPTICALCHANNEL                = 0xc3
+	IFT_OPTICALTRANSPORT              = 0xc4
+	IFT_OTHER                         = 0x1
+	IFT_P10                           = 0xc
+	IFT_P80                           = 0xd
+	IFT_PARA                          = 0x22
+	IFT_PFLOG                         = 0xf6
+	IFT_PFSYNC                        = 0xf7
+	IFT_PLC                           = 0xae
+	IFT_POS                           = 0xab
+	IFT_PPPMULTILINKBUNDLE            = 0x6c
+	IFT_PROPBWAP2MP                   = 0xb8
+	IFT_PROPCNLS                      = 0x59
+	IFT_PROPDOCSWIRELESSDOWNSTREAM    = 0xb5
+	IFT_PROPDOCSWIRELESSMACLAYER      = 0xb4
+	IFT_PROPDOCSWIRELESSUPSTREAM      = 0xb6
+	IFT_PROPMUX                       = 0x36
+	IFT_PROPWIRELESSP2P               = 0x9d
+	IFT_PTPSERIAL                     = 0x16
+	IFT_PVC                           = 0xf1
+	IFT_QLLC                          = 0x44
+	IFT_RADIOMAC                      = 0xbc
+	IFT_RADSL                         = 0x5f
+	IFT_REACHDSL                      = 0xc0
+	IFT_RFC1483                       = 0x9f
+	IFT_RS232                         = 0x21
+	IFT_RSRB                          = 0x4f
+	IFT_SDLC                          = 0x11
+	IFT_SDSL                          = 0x60
+	IFT_SHDSL                         = 0xa9
+	IFT_SIP                           = 0x1f
+	IFT_SLIP                          = 0x1c
+	IFT_SMDSDXI                       = 0x2b
+	IFT_SMDSICIP                      = 0x34
+	IFT_SONET                         = 0x27
+	IFT_SONETOVERHEADCHANNEL          = 0xb9
+	IFT_SONETPATH                     = 0x32
+	IFT_SONETVT                       = 0x33
+	IFT_SRP                           = 0x97
+	IFT_SS7SIGLINK                    = 0x9c
+	IFT_STACKTOSTACK                  = 0x6f
+	IFT_STARLAN                       = 0xb
+	IFT_STF                           = 0xd7
+	IFT_T1                            = 0x12
+	IFT_TDLC                          = 0x74
+	IFT_TERMPAD                       = 0x5b
+	IFT_TR008                         = 0xb0
+	IFT_TRANSPHDLC                    = 0x7b
+	IFT_TUNNEL                        = 0x83
+	IFT_ULTRA                         = 0x1d
+	IFT_USB                           = 0xa0
+	IFT_V11                           = 0x40
+	IFT_V35                           = 0x2d
+	IFT_V36                           = 0x41
+	IFT_V37                           = 0x78
+	IFT_VDSL                          = 0x61
+	IFT_VIRTUALIPADDRESS              = 0x70
+	IFT_VOICEEM                       = 0x64
+	IFT_VOICEENCAP                    = 0x67
+	IFT_VOICEFXO                      = 0x65
+	IFT_VOICEFXS                      = 0x66
+	IFT_VOICEOVERATM                  = 0x98
+	IFT_VOICEOVERFRAMERELAY           = 0x99
+	IFT_VOICEOVERIP                   = 0x68
+	IFT_X213                          = 0x5d
+	IFT_X25                           = 0x5
+	IFT_X25DDN                        = 0x4
+	IFT_X25HUNTGROUP                  = 0x7a
+	IFT_X25MLP                        = 0x79
+	IFT_X25PLE                        = 0x28
+	IFT_XETHER                        = 0x1a
+	IPPROTO_MAXID                     = 0x34
+	IPV6_FAITH                        = 0x1d
+	IP_FAITH                          = 0x16
+	MAP_NORESERVE                     = 0x40
+	MAP_RENAME                        = 0x20
+	NET_RT_MAXID                      = 0x6
+	RTF_PRCLONING                     = 0x10000
+	RTM_OLDADD                        = 0x9
+	RTM_OLDDEL                        = 0xa
+	SIOCADDRT                         = 0x8030720a
+	SIOCALIFADDR                      = 0x8118691b
+	SIOCDELRT                         = 0x8030720b
+	SIOCDLIFADDR                      = 0x8118691d
+	SIOCGLIFADDR                      = 0xc118691c
+	SIOCGLIFPHYADDR                   = 0xc118694b
+	SIOCSLIFPHYADDR                   = 0x8118694a
+)

vendor/golang.org/x/sys/unix/errors_freebsd_amd64.go

@@ -0,0 +1,227 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Constants that were deprecated or moved to enums in the FreeBSD headers. Keep
+// them here for backwards compatibility.
+
+package unix
+
+const (
+	IFF_SMART                         = 0x20
+	IFT_1822                          = 0x2
+	IFT_A12MPPSWITCH                  = 0x82
+	IFT_AAL2                          = 0xbb
+	IFT_AAL5                          = 0x31
+	IFT_ADSL                          = 0x5e
+	IFT_AFLANE8023                    = 0x3b
+	IFT_AFLANE8025                    = 0x3c
+	IFT_ARAP                          = 0x58
+	IFT_ARCNET                        = 0x23
+	IFT_ARCNETPLUS                    = 0x24
+	IFT_ASYNC                         = 0x54
+	IFT_ATM                           = 0x25
+	IFT_ATMDXI                        = 0x69
+	IFT_ATMFUNI                       = 0x6a
+	IFT_ATMIMA                        = 0x6b
+	IFT_ATMLOGICAL                    = 0x50
+	IFT_ATMRADIO                      = 0xbd
+	IFT_ATMSUBINTERFACE               = 0x86
+	IFT_ATMVCIENDPT                   = 0xc2
+	IFT_ATMVIRTUAL                    = 0x95
+	IFT_BGPPOLICYACCOUNTING           = 0xa2
+	IFT_BSC                           = 0x53
+	IFT_CCTEMUL                       = 0x3d
+	IFT_CEPT                          = 0x13
+	IFT_CES                           = 0x85
+	IFT_CHANNEL                       = 0x46
+	IFT_CNR                           = 0x55
+	IFT_COFFEE                        = 0x84
+	IFT_COMPOSITELINK                 = 0x9b
+	IFT_DCN                           = 0x8d
+	IFT_DIGITALPOWERLINE              = 0x8a
+	IFT_DIGITALWRAPPEROVERHEADCHANNEL = 0xba
+	IFT_DLSW                          = 0x4a
+	IFT_DOCSCABLEDOWNSTREAM           = 0x80
+	IFT_DOCSCABLEMACLAYER             = 0x7f
+	IFT_DOCSCABLEUPSTREAM             = 0x81
+	IFT_DS0                           = 0x51
+	IFT_DS0BUNDLE                     = 0x52
+	IFT_DS1FDL                        = 0xaa
+	IFT_DS3                           = 0x1e
+	IFT_DTM                           = 0x8c
+	IFT_DVBASILN                      = 0xac
+	IFT_DVBASIOUT                     = 0xad
+	IFT_DVBRCCDOWNSTREAM              = 0x93
+	IFT_DVBRCCMACLAYER                = 0x92
+	IFT_DVBRCCUPSTREAM                = 0x94
+	IFT_ENC                           = 0xf4
+	IFT_EON                           = 0x19
+	IFT_EPLRS                         = 0x57
+	IFT_ESCON                         = 0x49
+	IFT_ETHER                         = 0x6
+	IFT_FAITH                         = 0xf2
+	IFT_FAST                          = 0x7d
+	IFT_FASTETHER                     = 0x3e
+	IFT_FASTETHERFX                   = 0x45
+	IFT_FDDI                          = 0xf
+	IFT_FIBRECHANNEL                  = 0x38
+	IFT_FRAMERELAYINTERCONNECT        = 0x3a
+	IFT_FRAMERELAYMPI                 = 0x5c
+	IFT_FRDLCIENDPT                   = 0xc1
+	IFT_FRELAY                        = 0x20
+	IFT_FRELAYDCE                     = 0x2c
+	IFT_FRF16MFRBUNDLE                = 0xa3
+	IFT_FRFORWARD                     = 0x9e
+	IFT_G703AT2MB                     = 0x43
+	IFT_G703AT64K                     = 0x42
+	IFT_GIF                           = 0xf0
+	IFT_GIGABITETHERNET               = 0x75
+	IFT_GR303IDT                      = 0xb2
+	IFT_GR303RDT                      = 0xb1
+	IFT_H323GATEKEEPER                = 0xa4
+	IFT_H323PROXY                     = 0xa5
+	IFT_HDH1822                       = 0x3
+	IFT_HDLC                          = 0x76
+	IFT_HDSL2                         = 0xa8
+	IFT_HIPERLAN2                     = 0xb7
+	IFT_HIPPI                         = 0x2f
+	IFT_HIPPIINTERFACE                = 0x39
+	IFT_HOSTPAD                       = 0x5a
+	IFT_HSSI                          = 0x2e
+	IFT_HY                            = 0xe
+	IFT_IBM370PARCHAN                 = 0x48
+	IFT_IDSL                          = 0x9a
+	IFT_IEEE80211                     = 0x47
+	IFT_IEEE80212                     = 0x37
+	IFT_IEEE8023ADLAG                 = 0xa1
+	IFT_IFGSN                         = 0x91
+	IFT_IMT                           = 0xbe
+	IFT_INTERLEAVE                    = 0x7c
+	IFT_IP                            = 0x7e
+	IFT_IPFORWARD                     = 0x8e
+	IFT_IPOVERATM                     = 0x72
+	IFT_IPOVERCDLC                    = 0x6d
+	IFT_IPOVERCLAW                    = 0x6e
+	IFT_IPSWITCH                      = 0x4e
+	IFT_IPXIP                         = 0xf9
+	IFT_ISDN                          = 0x3f
+	IFT_ISDNBASIC                     = 0x14
+	IFT_ISDNPRIMARY                   = 0x15
+	IFT_ISDNS                         = 0x4b
+	IFT_ISDNU                         = 0x4c
+	IFT_ISO88022LLC                   = 0x29
+	IFT_ISO88023                      = 0x7
+	IFT_ISO88024                      = 0x8
+	IFT_ISO88025                      = 0x9
+	IFT_ISO88025CRFPINT               = 0x62
+	IFT_ISO88025DTR                   = 0x56
+	IFT_ISO88025FIBER                 = 0x73
+	IFT_ISO88026                      = 0xa
+	IFT_ISUP                          = 0xb3
+	IFT_L3IPXVLAN                     = 0x89
+	IFT_LAPB                          = 0x10
+	IFT_LAPD                          = 0x4d
+	IFT_LAPF                          = 0x77
+	IFT_LOCALTALK                     = 0x2a
+	IFT_LOOP                          = 0x18
+	IFT_MEDIAMAILOVERIP               = 0x8b
+	IFT_MFSIGLINK                     = 0xa7
+	IFT_MIOX25                        = 0x26
+	IFT_MODEM                         = 0x30
+	IFT_MPC                           = 0x71
+	IFT_MPLS                          = 0xa6
+	IFT_MPLSTUNNEL                    = 0x96
+	IFT_MSDSL                         = 0x8f
+	IFT_MVL                           = 0xbf
+	IFT_MYRINET                       = 0x63
+	IFT_NFAS                          = 0xaf
+	IFT_NSIP                          = 0x1b
+	IFT_OPTICALCHANNEL                = 0xc3
+	IFT_OPTICALTRANSPORT              = 0xc4
+	IFT_OTHER                         = 0x1
+	IFT_P10                           = 0xc
+	IFT_P80                           = 0xd
+	IFT_PARA                          = 0x22
+	IFT_PFLOG                         = 0xf6
+	IFT_PFSYNC                        = 0xf7
+	IFT_PLC                           = 0xae
+	IFT_POS                           = 0xab
+	IFT_PPPMULTILINKBUNDLE            = 0x6c
+	IFT_PROPBWAP2MP                   = 0xb8
+	IFT_PROPCNLS                      = 0x59
+	IFT_PROPDOCSWIRELESSDOWNSTREAM    = 0xb5
+	IFT_PROPDOCSWIRELESSMACLAYER      = 0xb4
+	IFT_PROPDOCSWIRELESSUPSTREAM      = 0xb6
+	IFT_PROPMUX                       = 0x36
+	IFT_PROPWIRELESSP2P               = 0x9d
+	IFT_PTPSERIAL                     = 0x16
+	IFT_PVC                           = 0xf1
+	IFT_QLLC                          = 0x44
+	IFT_RADIOMAC                      = 0xbc
+	IFT_RADSL                         = 0x5f
+	IFT_REACHDSL                      = 0xc0
+	IFT_RFC1483                       = 0x9f
+	IFT_RS232                         = 0x21
+	IFT_RSRB                          = 0x4f
+	IFT_SDLC                          = 0x11
+	IFT_SDSL                          = 0x60
+	IFT_SHDSL                         = 0xa9
+	IFT_SIP                           = 0x1f
+	IFT_SLIP                          = 0x1c
+	IFT_SMDSDXI                       = 0x2b
+	IFT_SMDSICIP                      = 0x34
+	IFT_SONET                         = 0x27
+	IFT_SONETOVERHEADCHANNEL          = 0xb9
+	IFT_SONETPATH                     = 0x32
+	IFT_SONETVT                       = 0x33
+	IFT_SRP                           = 0x97
+	IFT_SS7SIGLINK                    = 0x9c
+	IFT_STACKTOSTACK                  = 0x6f
+	IFT_STARLAN                       = 0xb
+	IFT_STF                           = 0xd7
+	IFT_T1                            = 0x12
+	IFT_TDLC                          = 0x74
+	IFT_TERMPAD                       = 0x5b
+	IFT_TR008                         = 0xb0
+	IFT_TRANSPHDLC                    = 0x7b
+	IFT_TUNNEL                        = 0x83
+	IFT_ULTRA                         = 0x1d
+	IFT_USB                           = 0xa0
+	IFT_V11                           = 0x40
+	IFT_V35                           = 0x2d
+	IFT_V36                           = 0x41
+	IFT_V37                           = 0x78
+	IFT_VDSL                          = 0x61
+	IFT_VIRTUALIPADDRESS              = 0x70
+	IFT_VOICEEM                       = 0x64
+	IFT_VOICEENCAP                    = 0x67
+	IFT_VOICEFXO                      = 0x65
+	IFT_VOICEFXS                      = 0x66
+	IFT_VOICEOVERATM                  = 0x98
+	IFT_VOICEOVERFRAMERELAY           = 0x99
+	IFT_VOICEOVERIP                   = 0x68
+	IFT_X213                          = 0x5d
+	IFT_X25                           = 0x5
+	IFT_X25DDN                        = 0x4
+	IFT_X25HUNTGROUP                  = 0x7a
+	IFT_X25MLP                        = 0x79
+	IFT_X25PLE                        = 0x28
+	IFT_XETHER                        = 0x1a
+	IPPROTO_MAXID                     = 0x34
+	IPV6_FAITH                        = 0x1d
+	IP_FAITH                          = 0x16
+	MAP_NORESERVE                     = 0x40
+	MAP_RENAME                        = 0x20
+	NET_RT_MAXID                      = 0x6
+	RTF_PRCLONING                     = 0x10000
+	RTM_OLDADD                        = 0x9
+	RTM_OLDDEL                        = 0xa
+	SIOCADDRT                         = 0x8040720a
+	SIOCALIFADDR                      = 0x8118691b
+	SIOCDELRT                         = 0x8040720b
+	SIOCDLIFADDR                      = 0x8118691d
+	SIOCGLIFADDR                      = 0xc118691c
+	SIOCGLIFPHYADDR                   = 0xc118694b
+	SIOCSLIFPHYADDR                   = 0x8118694a
+)

vendor/golang.org/x/sys/unix/errors_freebsd_arm.go

@@ -0,0 +1,226 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package unix
+
+const (
+	IFT_1822                          = 0x2
+	IFT_A12MPPSWITCH                  = 0x82
+	IFT_AAL2                          = 0xbb
+	IFT_AAL5                          = 0x31
+	IFT_ADSL                          = 0x5e
+	IFT_AFLANE8023                    = 0x3b
+	IFT_AFLANE8025                    = 0x3c
+	IFT_ARAP                          = 0x58
+	IFT_ARCNET                        = 0x23
+	IFT_ARCNETPLUS                    = 0x24
+	IFT_ASYNC                         = 0x54
+	IFT_ATM                           = 0x25
+	IFT_ATMDXI                        = 0x69
+	IFT_ATMFUNI                       = 0x6a
+	IFT_ATMIMA                        = 0x6b
+	IFT_ATMLOGICAL                    = 0x50
+	IFT_ATMRADIO                      = 0xbd
+	IFT_ATMSUBINTERFACE               = 0x86
+	IFT_ATMVCIENDPT                   = 0xc2
+	IFT_ATMVIRTUAL                    = 0x95
+	IFT_BGPPOLICYACCOUNTING           = 0xa2
+	IFT_BSC                           = 0x53
+	IFT_CCTEMUL                       = 0x3d
+	IFT_CEPT                          = 0x13
+	IFT_CES                           = 0x85
+	IFT_CHANNEL                       = 0x46
+	IFT_CNR                           = 0x55
+	IFT_COFFEE                        = 0x84
+	IFT_COMPOSITELINK                 = 0x9b
+	IFT_DCN                           = 0x8d
+	IFT_DIGITALPOWERLINE              = 0x8a
+	IFT_DIGITALWRAPPEROVERHEADCHANNEL = 0xba
+	IFT_DLSW                          = 0x4a
+	IFT_DOCSCABLEDOWNSTREAM           = 0x80
+	IFT_DOCSCABLEMACLAYER             = 0x7f
+	IFT_DOCSCABLEUPSTREAM             = 0x81
+	IFT_DS0                           = 0x51
+	IFT_DS0BUNDLE                     = 0x52
+	IFT_DS1FDL                        = 0xaa
+	IFT_DS3                           = 0x1e
+	IFT_DTM                           = 0x8c
+	IFT_DVBASILN                      = 0xac
+	IFT_DVBASIOUT                     = 0xad
+	IFT_DVBRCCDOWNSTREAM              = 0x93
+	IFT_DVBRCCMACLAYER                = 0x92
+	IFT_DVBRCCUPSTREAM                = 0x94
+	IFT_ENC                           = 0xf4
+	IFT_EON                           = 0x19
+	IFT_EPLRS                         = 0x57
+	IFT_ESCON                         = 0x49
+	IFT_ETHER                         = 0x6
+	IFT_FAST                          = 0x7d
+	IFT_FASTETHER                     = 0x3e
+	IFT_FASTETHERFX                   = 0x45
+	IFT_FDDI                          = 0xf
+	IFT_FIBRECHANNEL                  = 0x38
+	IFT_FRAMERELAYINTERCONNECT        = 0x3a
+	IFT_FRAMERELAYMPI                 = 0x5c
+	IFT_FRDLCIENDPT                   = 0xc1
+	IFT_FRELAY                        = 0x20
+	IFT_FRELAYDCE                     = 0x2c
+	IFT_FRF16MFRBUNDLE                = 0xa3
+	IFT_FRFORWARD                     = 0x9e
+	IFT_G703AT2MB                     = 0x43
+	IFT_G703AT64K                     = 0x42
+	IFT_GIF                           = 0xf0
+	IFT_GIGABITETHERNET               = 0x75
+	IFT_GR303IDT                      = 0xb2
+	IFT_GR303RDT                      = 0xb1
+	IFT_H323GATEKEEPER                = 0xa4
+	IFT_H323PROXY                     = 0xa5
+	IFT_HDH1822                       = 0x3
+	IFT_HDLC                          = 0x76
+	IFT_HDSL2                         = 0xa8
+	IFT_HIPERLAN2                     = 0xb7
+	IFT_HIPPI                         = 0x2f
+	IFT_HIPPIINTERFACE                = 0x39
+	IFT_HOSTPAD                       = 0x5a
+	IFT_HSSI                          = 0x2e
+	IFT_HY                            = 0xe
+	IFT_IBM370PARCHAN                 = 0x48
+	IFT_IDSL                          = 0x9a
+	IFT_IEEE80211                     = 0x47
+	IFT_IEEE80212                     = 0x37
+	IFT_IEEE8023ADLAG                 = 0xa1
+	IFT_IFGSN                         = 0x91
+	IFT_IMT                           = 0xbe
+	IFT_INTERLEAVE                    = 0x7c
+	IFT_IP                            = 0x7e
+	IFT_IPFORWARD                     = 0x8e
+	IFT_IPOVERATM                     = 0x72
+	IFT_IPOVERCDLC                    = 0x6d
+	IFT_IPOVERCLAW                    = 0x6e
+	IFT_IPSWITCH                      = 0x4e
+	IFT_ISDN                          = 0x3f
+	IFT_ISDNBASIC                     = 0x14
+	IFT_ISDNPRIMARY                   = 0x15
+	IFT_ISDNS                         = 0x4b
+	IFT_ISDNU                         = 0x4c
+	IFT_ISO88022LLC                   = 0x29
+	IFT_ISO88023                      = 0x7
+	IFT_ISO88024                      = 0x8
+	IFT_ISO88025                      = 0x9
+	IFT_ISO88025CRFPINT               = 0x62
+	IFT_ISO88025DTR                   = 0x56
+	IFT_ISO88025FIBER                 = 0x73
+	IFT_ISO88026                      = 0xa
+	IFT_ISUP                          = 0xb3
+	IFT_L3IPXVLAN                     = 0x89
+	IFT_LAPB                          = 0x10
+	IFT_LAPD                          = 0x4d
+	IFT_LAPF                          = 0x77
+	IFT_LOCALTALK                     = 0x2a
+	IFT_LOOP                          = 0x18
+	IFT_MEDIAMAILOVERIP               = 0x8b
+	IFT_MFSIGLINK                     = 0xa7
+	IFT_MIOX25                        = 0x26
+	IFT_MODEM                         = 0x30
+	IFT_MPC                           = 0x71
+	IFT_MPLS                          = 0xa6
+	IFT_MPLSTUNNEL                    = 0x96
+	IFT_MSDSL                         = 0x8f
+	IFT_MVL                           = 0xbf
+	IFT_MYRINET                       = 0x63
+	IFT_NFAS                          = 0xaf
+	IFT_NSIP                          = 0x1b
+	IFT_OPTICALCHANNEL                = 0xc3
+	IFT_OPTICALTRANSPORT              = 0xc4
+	IFT_OTHER                         = 0x1
+	IFT_P10                           = 0xc
+	IFT_P80                           = 0xd
+	IFT_PARA                          = 0x22
+	IFT_PFLOG                         = 0xf6
+	IFT_PFSYNC                        = 0xf7
+	IFT_PLC                           = 0xae
+	IFT_POS                           = 0xab
+	IFT_PPPMULTILINKBUNDLE            = 0x6c
+	IFT_PROPBWAP2MP                   = 0xb8
+	IFT_PROPCNLS                      = 0x59
+	IFT_PROPDOCSWIRELESSDOWNSTREAM    = 0xb5
+	IFT_PROPDOCSWIRELESSMACLAYER      = 0xb4
+	IFT_PROPDOCSWIRELESSUPSTREAM      = 0xb6
+	IFT_PROPMUX                       = 0x36
+	IFT_PROPWIRELESSP2P               = 0x9d
+	IFT_PTPSERIAL                     = 0x16
+	IFT_PVC                           = 0xf1
+	IFT_QLLC                          = 0x44
+	IFT_RADIOMAC                      = 0xbc
+	IFT_RADSL                         = 0x5f
+	IFT_REACHDSL                      = 0xc0
+	IFT_RFC1483                       = 0x9f
+	IFT_RS232                         = 0x21
+	IFT_RSRB                          = 0x4f
+	IFT_SDLC                          = 0x11
+	IFT_SDSL                          = 0x60
+	IFT_SHDSL                         = 0xa9
+	IFT_SIP                           = 0x1f
+	IFT_SLIP                          = 0x1c
+	IFT_SMDSDXI                       = 0x2b
+	IFT_SMDSICIP                      = 0x34
+	IFT_SONET                         = 0x27
+	IFT_SONETOVERHEADCHANNEL          = 0xb9
+	IFT_SONETPATH                     = 0x32
+	IFT_SONETVT                       = 0x33
+	IFT_SRP                           = 0x97
+	IFT_SS7SIGLINK                    = 0x9c
+	IFT_STACKTOSTACK                  = 0x6f
+	IFT_STARLAN                       = 0xb
+	IFT_STF                           = 0xd7
+	IFT_T1                            = 0x12
+	IFT_TDLC                          = 0x74
+	IFT_TERMPAD                       = 0x5b
+	IFT_TR008                         = 0xb0
+	IFT_TRANSPHDLC                    = 0x7b
+	IFT_TUNNEL                        = 0x83
+	IFT_ULTRA                         = 0x1d
+	IFT_USB                           = 0xa0
+	IFT_V11                           = 0x40
+	IFT_V35                           = 0x2d
+	IFT_V36                           = 0x41
+	IFT_V37                           = 0x78
+	IFT_VDSL                          = 0x61
+	IFT_VIRTUALIPADDRESS              = 0x70
+	IFT_VOICEEM                       = 0x64
+	IFT_VOICEENCAP                    = 0x67
+	IFT_VOICEFXO                      = 0x65
+	IFT_VOICEFXS                      = 0x66
+	IFT_VOICEOVERATM                  = 0x98
+	IFT_VOICEOVERFRAMERELAY           = 0x99
+	IFT_VOICEOVERIP                   = 0x68
+	IFT_X213                          = 0x5d
+	IFT_X25                           = 0x5
+	IFT_X25DDN                        = 0x4
+	IFT_X25HUNTGROUP                  = 0x7a
+	IFT_X25MLP                        = 0x79
+	IFT_X25PLE                        = 0x28
+	IFT_XETHER                        = 0x1a
+
+	// missing constants on FreeBSD-11.1-RELEASE, copied from old values in ztypes_freebsd_arm.go
+	IFF_SMART       = 0x20
+	IFT_FAITH       = 0xf2
+	IFT_IPXIP       = 0xf9
+	IPPROTO_MAXID   = 0x34
+	IPV6_FAITH      = 0x1d
+	IP_FAITH        = 0x16
+	MAP_NORESERVE   = 0x40
+	MAP_RENAME      = 0x20
+	NET_RT_MAXID    = 0x6
+	RTF_PRCLONING   = 0x10000
+	RTM_OLDADD      = 0x9
+	RTM_OLDDEL      = 0xa
+	SIOCADDRT       = 0x8030720a
+	SIOCALIFADDR    = 0x8118691b
+	SIOCDELRT       = 0x8030720b
+	SIOCDLIFADDR    = 0x8118691d
+	SIOCGLIFADDR    = 0xc118691c
+	SIOCGLIFPHYADDR = 0xc118694b
+	SIOCSLIFPHYADDR = 0x8118694a
+)

vendor/golang.org/x/sys/unix/flock.go

@@ -0,0 +1,22 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+package unix
+
+import "unsafe"
+
+// fcntl64Syscall is usually SYS_FCNTL, but is overridden on 32-bit Linux
+// systems by flock_linux_32bit.go to be SYS_FCNTL64.
+var fcntl64Syscall uintptr = SYS_FCNTL
+
+// FcntlFlock performs a fcntl syscall for the F_GETLK, F_SETLK or F_SETLKW command.
+func FcntlFlock(fd uintptr, cmd int, lk *Flock_t) error {
+	_, _, errno := Syscall(fcntl64Syscall, fd, uintptr(cmd), uintptr(unsafe.Pointer(lk)))
+	if errno == 0 {
+		return nil
+	}
+	return errno
+}

vendor/golang.org/x/sys/unix/flock_linux_32bit.go

@@ -0,0 +1,13 @@
+// +build linux,386 linux,arm linux,mips linux,mipsle
+
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package unix
+
+func init() {
+	// On 32-bit Linux systems, the fcntl syscall that matches Go's
+	// Flock_t type is SYS_FCNTL64, not SYS_FCNTL.
+	fcntl64Syscall = SYS_FCNTL64
+}

vendor/golang.org/x/sys/unix/gccgo.go

@@ -0,0 +1,46 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build gccgo
+
+package unix
+
+import "syscall"
+
+// We can't use the gc-syntax .s files for gccgo. On the plus side
+// much of the functionality can be written directly in Go.
+
+//extern gccgoRealSyscall
+func realSyscall(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r, errno uintptr)
+
+func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.Errno) {
+	syscall.Entersyscall()
+	r, errno := realSyscall(trap, a1, a2, a3, 0, 0, 0, 0, 0, 0)
+	syscall.Exitsyscall()
+	return r, 0, syscall.Errno(errno)
+}
+
+func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.Errno) {
+	syscall.Entersyscall()
+	r, errno := realSyscall(trap, a1, a2, a3, a4, a5, a6, 0, 0, 0)
+	syscall.Exitsyscall()
+	return r, 0, syscall.Errno(errno)
+}
+
+func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err syscall.Errno) {
+	syscall.Entersyscall()
+	r, errno := realSyscall(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9)
+	syscall.Exitsyscall()
+	return r, 0, syscall.Errno(errno)
+}
+
+func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.Errno) {
+	r, errno := realSyscall(trap, a1, a2, a3, 0, 0, 0, 0, 0, 0)
+	return r, 0, syscall.Errno(errno)
+}
+
+func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.Errno) {
+	r, errno := realSyscall(trap, a1, a2, a3, a4, a5, a6, 0, 0, 0)
+	return r, 0, syscall.Errno(errno)
+}

vendor/golang.org/x/sys/unix/gccgo_c.c

@@ -0,0 +1,41 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build gccgo
+
+#include <errno.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#define _STRINGIFY2_(x) #x
+#define _STRINGIFY_(x) _STRINGIFY2_(x)
+#define GOSYM_PREFIX _STRINGIFY_(__USER_LABEL_PREFIX__)
+
+// Call syscall from C code because the gccgo support for calling from
+// Go to C does not support varargs functions.
+
+struct ret {
+	uintptr_t r;
+	uintptr_t err;
+};
+
+struct ret
+gccgoRealSyscall(uintptr_t trap, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintptr_t a4, uintptr_t a5, uintptr_t a6, uintptr_t a7, uintptr_t a8, uintptr_t a9)
+{
+	struct ret r;
+
+	errno = 0;
+	r.r = syscall(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9);
+	r.err = errno;
+	return r;
+}
+
+// Define the use function in C so that it is not inlined.
+
+extern void use(void *) __asm__ (GOSYM_PREFIX GOPKGPATH ".use") __attribute__((noinline));
+
+void
+use(void *p __attribute__ ((unused)))
+{
+}

vendor/golang.org/x/sys/unix/gccgo_linux_amd64.go

@@ -0,0 +1,20 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build gccgo,linux,amd64
+
+package unix
+
+import "syscall"
+
+//extern gettimeofday
+func realGettimeofday(*Timeval, *byte) int32
+
+func gettimeofday(tv *Timeval) (err syscall.Errno) {
+	r := realGettimeofday(tv, nil)
+	if r < 0 {
+		return syscall.GetErrno()
+	}
+	return 0
+}

vendor/golang.org/x/sys/unix/mkall.sh

@@ -0,0 +1,194 @@
+#!/usr/bin/env bash
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# This script runs or (given -n) prints suggested commands to generate files for
+# the Architecture/OS specified by the GOARCH and GOOS environment variables.
+# See README.md for more information about how the build system works.
+
+GOOSARCH="${GOOS}_${GOARCH}"
+
+# defaults
+mksyscall="./mksyscall.pl"
+mkerrors="./mkerrors.sh"
+zerrors="zerrors_$GOOSARCH.go"
+mksysctl=""
+zsysctl="zsysctl_$GOOSARCH.go"
+mksysnum=
+mktypes=
+run="sh"
+cmd=""
+
+case "$1" in
+-syscalls)
+	for i in zsyscall*go
+	do
+		# Run the command line that appears in the first line
+		# of the generated file to regenerate it.
+		sed 1q $i | sed 's;^// ;;' | sh > _$i && gofmt < _$i > $i
+		rm _$i
+	done
+	exit 0
+	;;
+-n)
+	run="cat"
+	cmd="echo"
+	shift
+esac
+
+case "$#" in
+0)
+	;;
+*)
+	echo 'usage: mkall.sh [-n]' 1>&2
+	exit 2
+esac
+
+if [[ "$GOOS" = "linux" ]] && [[ "$GOARCH" != "sparc64" ]]; then
+	# Use then new build system
+	# Files generated through docker (use $cmd so you can Ctl-C the build or run)
+	$cmd docker build --tag generate:$GOOS $GOOS
+	$cmd docker run --interactive --tty --volume $(dirname "$(readlink -f "$0")"):/build generate:$GOOS
+	exit
+fi
+
+GOOSARCH_in=syscall_$GOOSARCH.go
+case "$GOOSARCH" in
+_* | *_ | _)
+	echo 'undefined $GOOS_$GOARCH:' "$GOOSARCH" 1>&2
+	exit 1
+	;;
+darwin_386)
+	mkerrors="$mkerrors -m32"
+	mksyscall="./mksyscall.pl -l32"
+	mksysnum="./mksysnum_darwin.pl $(xcrun --show-sdk-path --sdk macosx)/usr/include/sys/syscall.h"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+darwin_amd64)
+	mkerrors="$mkerrors -m64"
+	mksysnum="./mksysnum_darwin.pl $(xcrun --show-sdk-path --sdk macosx)/usr/include/sys/syscall.h"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+darwin_arm)
+	mkerrors="$mkerrors"
+	mksysnum="./mksysnum_darwin.pl $(xcrun --show-sdk-path --sdk iphoneos)/usr/include/sys/syscall.h"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+darwin_arm64)
+	mkerrors="$mkerrors -m64"
+	mksysnum="./mksysnum_darwin.pl $(xcrun --show-sdk-path --sdk iphoneos)/usr/include/sys/syscall.h"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+dragonfly_386)
+	mkerrors="$mkerrors -m32"
+	mksyscall="./mksyscall.pl -l32 -dragonfly"
+	mksysnum="curl -s 'http://gitweb.dragonflybsd.org/dragonfly.git/blob_plain/HEAD:/sys/kern/syscalls.master' | ./mksysnum_dragonfly.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+dragonfly_amd64)
+	mkerrors="$mkerrors -m64"
+	mksyscall="./mksyscall.pl -dragonfly"
+	mksysnum="curl -s 'http://gitweb.dragonflybsd.org/dragonfly.git/blob_plain/HEAD:/sys/kern/syscalls.master' | ./mksysnum_dragonfly.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+freebsd_386)
+	mkerrors="$mkerrors -m32"
+	mksyscall="./mksyscall.pl -l32"
+	mksysnum="curl -s 'http://svn.freebsd.org/base/stable/10/sys/kern/syscalls.master' | ./mksysnum_freebsd.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+freebsd_amd64)
+	mkerrors="$mkerrors -m64"
+	mksysnum="curl -s 'http://svn.freebsd.org/base/stable/10/sys/kern/syscalls.master' | ./mksysnum_freebsd.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+freebsd_arm)
+	mkerrors="$mkerrors"
+	mksyscall="./mksyscall.pl -l32 -arm"
+	mksysnum="curl -s 'http://svn.freebsd.org/base/stable/10/sys/kern/syscalls.master' | ./mksysnum_freebsd.pl"
+	# Let the type of C char be signed for making the bare syscall
+	# API consistent across platforms.
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs -- -fsigned-char"
+	;;
+linux_sparc64)
+	GOOSARCH_in=syscall_linux_sparc64.go
+	unistd_h=/usr/include/sparc64-linux-gnu/asm/unistd.h
+	mkerrors="$mkerrors -m64"
+	mksysnum="./mksysnum_linux.pl $unistd_h"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+netbsd_386)
+	mkerrors="$mkerrors -m32"
+	mksyscall="./mksyscall.pl -l32 -netbsd"
+	mksysnum="curl -s 'http://cvsweb.netbsd.org/bsdweb.cgi/~checkout~/src/sys/kern/syscalls.master' | ./mksysnum_netbsd.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+netbsd_amd64)
+	mkerrors="$mkerrors -m64"
+	mksyscall="./mksyscall.pl -netbsd"
+	mksysnum="curl -s 'http://cvsweb.netbsd.org/bsdweb.cgi/~checkout~/src/sys/kern/syscalls.master' | ./mksysnum_netbsd.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+netbsd_arm)
+	mkerrors="$mkerrors"
+	mksyscall="./mksyscall.pl -l32 -netbsd -arm"
+	mksysnum="curl -s 'http://cvsweb.netbsd.org/bsdweb.cgi/~checkout~/src/sys/kern/syscalls.master' | ./mksysnum_netbsd.pl"
+	# Let the type of C char be signed for making the bare syscall
+	# API consistent across platforms.
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs -- -fsigned-char"
+	;;
+openbsd_386)
+	mkerrors="$mkerrors -m32"
+	mksyscall="./mksyscall.pl -l32 -openbsd"
+	mksysctl="./mksysctl_openbsd.pl"
+	mksysnum="curl -s 'http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/kern/syscalls.master' | ./mksysnum_openbsd.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+openbsd_amd64)
+	mkerrors="$mkerrors -m64"
+	mksyscall="./mksyscall.pl -openbsd"
+	mksysctl="./mksysctl_openbsd.pl"
+	mksysnum="curl -s 'http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/kern/syscalls.master' | ./mksysnum_openbsd.pl"
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+openbsd_arm)
+	mkerrors="$mkerrors"
+	mksyscall="./mksyscall.pl -l32 -openbsd -arm"
+	mksysctl="./mksysctl_openbsd.pl"
+	mksysnum="curl -s 'http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/kern/syscalls.master' | ./mksysnum_openbsd.pl"
+	# Let the type of C char be signed for making the bare syscall
+	# API consistent across platforms.
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs -- -fsigned-char"
+	;;
+solaris_amd64)
+	mksyscall="./mksyscall_solaris.pl"
+	mkerrors="$mkerrors -m64"
+	mksysnum=
+	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
+	;;
+*)
+	echo 'unrecognized $GOOS_$GOARCH: ' "$GOOSARCH" 1>&2
+	exit 1
+	;;
+esac
+
+(
+	if [ -n "$mkerrors" ]; then echo "$mkerrors |gofmt >$zerrors"; fi
+	case "$GOOS" in
+	*)
+		syscall_goos="syscall_$GOOS.go"
+		case "$GOOS" in
+		darwin | dragonfly | freebsd | netbsd | openbsd)
+			syscall_goos="syscall_bsd.go $syscall_goos"
+			;;
+		esac
+		if [ -n "$mksyscall" ]; then echo "$mksyscall -tags $GOOS,$GOARCH $syscall_goos $GOOSARCH_in |gofmt >zsyscall_$GOOSARCH.go"; fi
+		;;
+	esac
+	if [ -n "$mksysctl" ]; then echo "$mksysctl |gofmt >$zsysctl"; fi
+	if [ -n "$mksysnum" ]; then echo "$mksysnum |gofmt >zsysnum_$GOOSARCH.go"; fi
+	if [ -n "$mktypes" ]; then
+		echo "$mktypes types_$GOOS.go | go run mkpost.go > ztypes_$GOOSARCH.go";
+	fi
+) | $run

vendor/golang.org/x/sys/unix/mkerrors.sh

@@ -0,0 +1,577 @@
+#!/usr/bin/env bash
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# Generate Go code listing errors and other #defined constant
+# values (ENAMETOOLONG etc.), by asking the preprocessor
+# about the definitions.
+
+unset LANG
+export LC_ALL=C
+export LC_CTYPE=C
+
+if test -z "$GOARCH" -o -z "$GOOS"; then
+	echo 1>&2 "GOARCH or GOOS not defined in environment"
+	exit 1
+fi
+
+# Check that we are using the new build system if we should
+if [[ "$GOOS" = "linux" ]] && [[ "$GOARCH" != "sparc64" ]]; then
+	if [[ "$GOLANG_SYS_BUILD" != "docker" ]]; then
+		echo 1>&2 "In the new build system, mkerrors should not be called directly."
+		echo 1>&2 "See README.md"
+		exit 1
+	fi
+fi
+
+CC=${CC:-cc}
+
+if [[ "$GOOS" = "solaris" ]]; then
+	# Assumes GNU versions of utilities in PATH.
+	export PATH=/usr/gnu/bin:$PATH
+fi
+
+uname=$(uname)
+
+includes_Darwin='
+#define _DARWIN_C_SOURCE
+#define KERNEL
+#define _DARWIN_USE_64_BIT_INODE
+#include <stdint.h>
+#include <sys/attr.h>
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/ptrace.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/sysctl.h>
+#include <sys/mman.h>
+#include <sys/mount.h>
+#include <sys/utsname.h>
+#include <sys/wait.h>
+#include <net/bpf.h>
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <termios.h>
+'
+
+includes_DragonFly='
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/sysctl.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <sys/ioctl.h>
+#include <net/bpf.h>
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <termios.h>
+#include <netinet/ip.h>
+#include <net/ip_mroute/ip_mroute.h>
+'
+
+includes_FreeBSD='
+#include <sys/capability.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/sysctl.h>
+#include <sys/mman.h>
+#include <sys/mount.h>
+#include <sys/wait.h>
+#include <sys/ioctl.h>
+#include <net/bpf.h>
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <termios.h>
+#include <netinet/ip.h>
+#include <netinet/ip_mroute.h>
+#include <sys/extattr.h>
+
+#if __FreeBSD__ >= 10
+#define IFT_CARP	0xf8	// IFT_CARP is deprecated in FreeBSD 10
+#undef SIOCAIFADDR
+#define SIOCAIFADDR	_IOW(105, 26, struct oifaliasreq)	// ifaliasreq contains if_data
+#undef SIOCSIFPHYADDR
+#define SIOCSIFPHYADDR	_IOW(105, 70, struct oifaliasreq)	// ifaliasreq contains if_data
+#endif
+'
+
+includes_Linux='
+#define _LARGEFILE_SOURCE
+#define _LARGEFILE64_SOURCE
+#ifndef __LP64__
+#define _FILE_OFFSET_BITS 64
+#endif
+#define _GNU_SOURCE
+
+// <sys/ioctl.h> is broken on powerpc64, as it fails to include definitions of
+// these structures. We just include them copied from <bits/termios.h>.
+#if defined(__powerpc__)
+struct sgttyb {
+        char    sg_ispeed;
+        char    sg_ospeed;
+        char    sg_erase;
+        char    sg_kill;
+        short   sg_flags;
+};
+
+struct tchars {
+        char    t_intrc;
+        char    t_quitc;
+        char    t_startc;
+        char    t_stopc;
+        char    t_eofc;
+        char    t_brkc;
+};
+
+struct ltchars {
+        char    t_suspc;
+        char    t_dsuspc;
+        char    t_rprntc;
+        char    t_flushc;
+        char    t_werasc;
+        char    t_lnextc;
+};
+#endif
+
+#include <bits/sockaddr.h>
+#include <sys/epoll.h>
+#include <sys/eventfd.h>
+#include <sys/inotify.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/mount.h>
+#include <sys/prctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <sys/xattr.h>
+#include <linux/if.h>
+#include <linux/if_alg.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/if_tun.h>
+#include <linux/if_packet.h>
+#include <linux/if_addr.h>
+#include <linux/falloc.h>
+#include <linux/filter.h>
+#include <linux/fs.h>
+#include <linux/keyctl.h>
+#include <linux/netlink.h>
+#include <linux/perf_event.h>
+#include <linux/random.h>
+#include <linux/reboot.h>
+#include <linux/rtnetlink.h>
+#include <linux/ptrace.h>
+#include <linux/sched.h>
+#include <linux/seccomp.h>
+#include <linux/sockios.h>
+#include <linux/wait.h>
+#include <linux/icmpv6.h>
+#include <linux/serial.h>
+#include <linux/can.h>
+#include <linux/vm_sockets.h>
+#include <linux/taskstats.h>
+#include <linux/genetlink.h>
+#include <linux/watchdog.h>
+#include <net/route.h>
+#include <asm/termbits.h>
+
+#ifndef MSG_FASTOPEN
+#define MSG_FASTOPEN    0x20000000
+#endif
+
+#ifndef PTRACE_GETREGS
+#define PTRACE_GETREGS	0xc
+#endif
+
+#ifndef PTRACE_SETREGS
+#define PTRACE_SETREGS	0xd
+#endif
+
+#ifndef SOL_NETLINK
+#define SOL_NETLINK	270
+#endif
+
+#ifdef SOL_BLUETOOTH
+// SPARC includes this in /usr/include/sparc64-linux-gnu/bits/socket.h
+// but it is already in bluetooth_linux.go
+#undef SOL_BLUETOOTH
+#endif
+
+// Certain constants are missing from the fs/crypto UAPI
+#define FS_KEY_DESC_PREFIX              "fscrypt:"
+#define FS_KEY_DESC_PREFIX_SIZE         8
+#define FS_MAX_KEY_SIZE                 64
+'
+
+includes_NetBSD='
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/event.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/sysctl.h>
+#include <sys/termios.h>
+#include <sys/ttycom.h>
+#include <sys/wait.h>
+#include <net/bpf.h>
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/ip_mroute.h>
+#include <netinet/if_ether.h>
+
+// Needed since <sys/param.h> refers to it...
+#define schedppq 1
+'
+
+includes_OpenBSD='
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/event.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/sysctl.h>
+#include <sys/termios.h>
+#include <sys/ttycom.h>
+#include <sys/wait.h>
+#include <net/bpf.h>
+#include <net/if.h>
+#include <net/if_types.h>
+#include <net/if_var.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/ip_mroute.h>
+#include <netinet/if_ether.h>
+#include <net/if_bridge.h>
+
+// We keep some constants not supported in OpenBSD 5.5 and beyond for
+// the promise of compatibility.
+#define EMUL_ENABLED		0x1
+#define EMUL_NATIVE		0x2
+#define IPV6_FAITH		0x1d
+#define IPV6_OPTIONS		0x1
+#define IPV6_RTHDR_STRICT	0x1
+#define IPV6_SOCKOPT_RESERVED1	0x3
+#define SIOCGIFGENERIC		0xc020693a
+#define SIOCSIFGENERIC		0x80206939
+#define WALTSIG			0x4
+'
+
+includes_SunOS='
+#include <limits.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <sys/ioctl.h>
+#include <sys/mkdev.h>
+#include <net/bpf.h>
+#include <net/if.h>
+#include <net/if_arp.h>
+#include <net/if_types.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <termios.h>
+#include <netinet/ip.h>
+#include <netinet/ip_mroute.h>
+'
+
+
+includes='
+#include <sys/types.h>
+#include <sys/file.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <errno.h>
+#include <sys/signal.h>
+#include <signal.h>
+#include <sys/resource.h>
+#include <time.h>
+'
+ccflags="$@"
+
+# Write go tool cgo -godefs input.
+(
+	echo package unix
+	echo
+	echo '/*'
+	indirect="includes_$(uname)"
+	echo "${!indirect} $includes"
+	echo '*/'
+	echo 'import "C"'
+	echo 'import "syscall"'
+	echo
+	echo 'const ('
+
+	# The gcc command line prints all the #defines
+	# it encounters while processing the input
+	echo "${!indirect} $includes" | $CC -x c - -E -dM $ccflags |
+	awk '
+		$1 != "#define" || $2 ~ /\(/ || $3 == "" {next}
+
+		$2 ~ /^E([ABCD]X|[BIS]P|[SD]I|S|FL)$/ {next}  # 386 registers
+		$2 ~ /^(SIGEV_|SIGSTKSZ|SIGRT(MIN|MAX))/ {next}
+		$2 ~ /^(SCM_SRCRT)$/ {next}
+		$2 ~ /^(MAP_FAILED)$/ {next}
+		$2 ~ /^ELF_.*$/ {next}# <asm/elf.h> contains ELF_ARCH, etc.
+
+		$2 ~ /^EXTATTR_NAMESPACE_NAMES/ ||
+		$2 ~ /^EXTATTR_NAMESPACE_[A-Z]+_STRING/ {next}
+
+		$2 !~ /^ETH_/ &&
+		$2 !~ /^EPROC_/ &&
+		$2 !~ /^EQUIV_/ &&
+		$2 !~ /^EXPR_/ &&
+		$2 ~ /^E[A-Z0-9_]+$/ ||
+		$2 ~ /^B[0-9_]+$/ ||
+		$2 ~ /^(OLD|NEW)DEV$/ ||
+		$2 == "BOTHER" ||
+		$2 ~ /^CI?BAUD(EX)?$/ ||
+		$2 == "IBSHIFT" ||
+		$2 ~ /^V[A-Z0-9]+$/ ||
+		$2 ~ /^CS[A-Z0-9]/ ||
+		$2 ~ /^I(SIG|CANON|CRNL|UCLC|EXTEN|MAXBEL|STRIP|UTF8)$/ ||
+		$2 ~ /^IGN/ ||
+		$2 ~ /^IX(ON|ANY|OFF)$/ ||
+		$2 ~ /^IN(LCR|PCK)$/ ||
+		$2 ~ /(^FLU?SH)|(FLU?SH$)/ ||
+		$2 ~ /^C(LOCAL|READ|MSPAR|RTSCTS)$/ ||
+		$2 == "BRKINT" ||
+		$2 == "HUPCL" ||
+		$2 == "PENDIN" ||
+		$2 == "TOSTOP" ||
+		$2 == "XCASE" ||
+		$2 == "ALTWERASE" ||
+		$2 == "NOKERNINFO" ||
+		$2 ~ /^PAR/ ||
+		$2 ~ /^SIG[^_]/ ||
+		$2 ~ /^O[CNPFPL][A-Z]+[^_][A-Z]+$/ ||
+		$2 ~ /^(NL|CR|TAB|BS|VT|FF)DLY$/ ||
+		$2 ~ /^(NL|CR|TAB|BS|VT|FF)[0-9]$/ ||
+		$2 ~ /^O?XTABS$/ ||
+		$2 ~ /^TC[IO](ON|OFF)$/ ||
+		$2 ~ /^IN_/ ||
+		$2 ~ /^LOCK_(SH|EX|NB|UN)$/ ||
+		$2 ~ /^(AF|SOCK|SO|SOL|IPPROTO|IP|IPV6|ICMP6|TCP|EVFILT|NOTE|EV|SHUT|PROT|MAP|PACKET|MSG|SCM|MCL|DT|MADV|PR)_/ ||
+		$2 ~ /^FALLOC_/ ||
+		$2 == "ICMPV6_FILTER" ||
+		$2 == "SOMAXCONN" ||
+		$2 == "NAME_MAX" ||
+		$2 == "IFNAMSIZ" ||
+		$2 ~ /^CTL_(HW|KERN|MAXNAME|NET|QUERY)$/ ||
+		$2 ~ /^KERN_(HOSTNAME|OS(RELEASE|TYPE)|VERSION)$/ ||
+		$2 ~ /^HW_MACHINE$/ ||
+		$2 ~ /^SYSCTL_VERS/ ||
+		$2 ~ /^(MS|MNT|UMOUNT)_/ ||
+		$2 ~ /^TUN(SET|GET|ATTACH|DETACH)/ ||
+		$2 ~ /^(O|F|E?FD|NAME|S|PTRACE|PT)_/ ||
+		$2 ~ /^LINUX_REBOOT_CMD_/ ||
+		$2 ~ /^LINUX_REBOOT_MAGIC[12]$/ ||
+		$2 !~ "NLA_TYPE_MASK" &&
+		$2 ~ /^(NETLINK|NLM|NLMSG|NLA|IFA|IFAN|RT|RTCF|RTN|RTPROT|RTNH|ARPHRD|ETH_P)_/ ||
+		$2 ~ /^SIOC/ ||
+		$2 ~ /^TIOC/ ||
+		$2 ~ /^TCGET/ ||
+		$2 ~ /^TCSET/ ||
+		$2 ~ /^TC(FLSH|SBRKP?|XONC)$/ ||
+		$2 !~ "RTF_BITS" &&
+		$2 ~ /^(IFF|IFT|NET_RT|RTM|RTF|RTV|RTA|RTAX)_/ ||
+		$2 ~ /^BIOC/ ||
+		$2 ~ /^RUSAGE_(SELF|CHILDREN|THREAD)/ ||
+		$2 ~ /^RLIMIT_(AS|CORE|CPU|DATA|FSIZE|LOCKS|MEMLOCK|MSGQUEUE|NICE|NOFILE|NPROC|RSS|RTPRIO|RTTIME|SIGPENDING|STACK)|RLIM_INFINITY/ ||
+		$2 ~ /^PRIO_(PROCESS|PGRP|USER)/ ||
+		$2 ~ /^CLONE_[A-Z_]+/ ||
+		$2 !~ /^(BPF_TIMEVAL)$/ &&
+		$2 ~ /^(BPF|DLT)_/ ||
+		$2 ~ /^CLOCK_/ ||
+		$2 ~ /^CAN_/ ||
+		$2 ~ /^CAP_/ ||
+		$2 ~ /^ALG_/ ||
+		$2 ~ /^FS_(POLICY_FLAGS|KEY_DESC|ENCRYPTION_MODE|[A-Z0-9_]+_KEY_SIZE|IOC_(GET|SET)_ENCRYPTION)/ ||
+		$2 ~ /^GRND_/ ||
+		$2 ~ /^KEY_(SPEC|REQKEY_DEFL)_/ ||
+		$2 ~ /^KEYCTL_/ ||
+		$2 ~ /^PERF_EVENT_IOC_/ ||
+		$2 ~ /^SECCOMP_MODE_/ ||
+		$2 ~ /^SPLICE_/ ||
+		$2 ~ /^(VM|VMADDR)_/ ||
+		$2 ~ /^IOCTL_VM_SOCKETS_/ ||
+		$2 ~ /^(TASKSTATS|TS)_/ ||
+		$2 ~ /^GENL_/ ||
+		$2 ~ /^UTIME_/ ||
+		$2 ~ /^XATTR_(CREATE|REPLACE)/ ||
+		$2 ~ /^ATTR_(BIT_MAP_COUNT|(CMN|VOL|FILE)_)/ ||
+		$2 ~ /^FSOPT_/ ||
+		$2 ~ /^WDIOC_/ ||
+		$2 !~ "WMESGLEN" &&
+		$2 ~ /^W[A-Z0-9]+$/ ||
+		$2 ~ /^BLK[A-Z]*(GET$|SET$|BUF$|PART$|SIZE)/ {printf("\t%s = C.%s\n", $2, $2)}
+		$2 ~ /^__WCOREFLAG$/ {next}
+		$2 ~ /^__W[A-Z0-9]+$/ {printf("\t%s = C.%s\n", substr($2,3), $2)}
+
+		{next}
+	' | sort
+
+	echo ')'
+) >_const.go
+
+# Pull out the error names for later.
+errors=$(
+	echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print $2 }' |
+	sort
+)
+
+# Pull out the signal names for later.
+signals=$(
+	echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print $2 }' |
+	egrep -v '(SIGSTKSIZE|SIGSTKSZ|SIGRT)' |
+	sort
+)
+
+# Again, writing regexps to a file.
+echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print "^\t" $2 "[ \t]*=" }' |
+	sort >_error.grep
+echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print "^\t" $2 "[ \t]*=" }' |
+	egrep -v '(SIGSTKSIZE|SIGSTKSZ|SIGRT)' |
+	sort >_signal.grep
+
+echo '// mkerrors.sh' "$@"
+echo '// Code generated by the command above; see README.md. DO NOT EDIT.'
+echo
+echo "// +build ${GOARCH},${GOOS}"
+echo
+go tool cgo -godefs -- "$@" _const.go >_error.out
+cat _error.out | grep -vf _error.grep | grep -vf _signal.grep
+echo
+echo '// Errors'
+echo 'const ('
+cat _error.out | grep -f _error.grep | sed 's/=\(.*\)/= syscall.Errno(\1)/'
+echo ')'
+
+echo
+echo '// Signals'
+echo 'const ('
+cat _error.out | grep -f _signal.grep | sed 's/=\(.*\)/= syscall.Signal(\1)/'
+echo ')'
+
+# Run C program to print error and syscall strings.
+(
+	echo -E "
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <string.h>
+#include <signal.h>
+
+#define nelem(x) (sizeof(x)/sizeof((x)[0]))
+
+enum { A = 'A', Z = 'Z', a = 'a', z = 'z' }; // avoid need for single quotes below
+
+int errors[] = {
+"
+	for i in $errors
+	do
+		echo -E '	'$i,
+	done
+
+	echo -E "
+};
+
+int signals[] = {
+"
+	for i in $signals
+	do
+		echo -E '	'$i,
+	done
+
+	# Use -E because on some systems bash builtin interprets \n itself.
+	echo -E '
+};
+
+static int
+intcmp(const void *a, const void *b)
+{
+	return *(int*)a - *(int*)b;
+}
+
+int
+main(void)
+{
+	int i, e;
+	char buf[1024], *p;
+
+	printf("\n\n// Error table\n");
+	printf("var errors = [...]string {\n");
+	qsort(errors, nelem(errors), sizeof errors[0], intcmp);
+	for(i=0; i<nelem(errors); i++) {
+		e = errors[i];
+		if(i > 0 && errors[i-1] == e)
+			continue;
+		strcpy(buf, strerror(e));
+		// lowercase first letter: Bad -> bad, but STREAM -> STREAM.
+		if(A <= buf[0] && buf[0] <= Z && a <= buf[1] && buf[1] <= z)
+			buf[0] += a - A;
+		printf("\t%d: \"%s\",\n", e, buf);
+	}
+	printf("}\n\n");
+
+	printf("\n\n// Signal table\n");
+	printf("var signals = [...]string {\n");
+	qsort(signals, nelem(signals), sizeof signals[0], intcmp);
+	for(i=0; i<nelem(signals); i++) {
+		e = signals[i];
+		if(i > 0 && signals[i-1] == e)
+			continue;
+		strcpy(buf, strsignal(e));
+		// lowercase first letter: Bad -> bad, but STREAM -> STREAM.
+		if(A <= buf[0] && buf[0] <= Z && a <= buf[1] && buf[1] <= z)
+			buf[0] += a - A;
+		// cut trailing : number.
+		p = strrchr(buf, ":"[0]);
+		if(p)
+			*p = '\0';
+		printf("\t%d: \"%s\",\n", e, buf);
+	}
+	printf("}\n\n");
+
+	return 0;
+}
+
+'
+) >_errors.c
+
+$CC $ccflags -o _errors _errors.c && $GORUN ./_errors && rm -f _errors.c _errors _const.go _error.grep _signal.grep _error.out

vendor/golang.org/x/sys/unix/mkpost.go

@@ -0,0 +1,93 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// mkpost processes the output of cgo -godefs to
+// modify the generated types. It is used to clean up
+// the sys API in an architecture specific manner.
+//
+// mkpost is run after cgo -godefs; see README.md.
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"go/format"
+	"io/ioutil"
+	"log"
+	"os"
+	"regexp"
+)
+
+func main() {
+	// Get the OS and architecture (using GOARCH_TARGET if it exists)
+	goos := os.Getenv("GOOS")
+	goarch := os.Getenv("GOARCH_TARGET")
+	if goarch == "" {
+		goarch = os.Getenv("GOARCH")
+	}
+	// Check that we are using the new build system if we should be.
+	if goos == "linux" && goarch != "sparc64" {
+		if os.Getenv("GOLANG_SYS_BUILD") != "docker" {
+			os.Stderr.WriteString("In the new build system, mkpost should not be called directly.\n")
+			os.Stderr.WriteString("See README.md\n")
+			os.Exit(1)
+		}
+	}
+
+	b, err := ioutil.ReadAll(os.Stdin)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// If we have empty Ptrace structs, we should delete them. Only s390x emits
+	// nonempty Ptrace structs.
+	ptraceRexexp := regexp.MustCompile(`type Ptrace((Psw|Fpregs|Per) struct {\s*})`)
+	b = ptraceRexexp.ReplaceAll(b, nil)
+
+	// Replace the control_regs union with a blank identifier for now.
+	controlRegsRegex := regexp.MustCompile(`(Control_regs)\s+\[0\]uint64`)
+	b = controlRegsRegex.ReplaceAll(b, []byte("_ [0]uint64"))
+
+	// Remove fields that are added by glibc
+	// Note that this is unstable as the identifers are private.
+	removeFieldsRegex := regexp.MustCompile(`X__glibc\S*`)
+	b = removeFieldsRegex.ReplaceAll(b, []byte("_"))
+
+	// Convert [65]int8 to [65]byte in Utsname members to simplify
+	// conversion to string; see golang.org/issue/20753
+	convertUtsnameRegex := regexp.MustCompile(`((Sys|Node|Domain)name|Release|Version|Machine)(\s+)\[(\d+)\]u?int8`)
+	b = convertUtsnameRegex.ReplaceAll(b, []byte("$1$3[$4]byte"))
+
+	// We refuse to export private fields on s390x
+	if goarch == "s390x" && goos == "linux" {
+		// Remove cgo padding fields
+		removeFieldsRegex := regexp.MustCompile(`Pad_cgo_\d+`)
+		b = removeFieldsRegex.ReplaceAll(b, []byte("_"))
+
+		// Remove padding, hidden, or unused fields
+		removeFieldsRegex = regexp.MustCompile(`X_\S+`)
+		b = removeFieldsRegex.ReplaceAll(b, []byte("_"))
+	}
+
+	// Remove the first line of warning from cgo
+	b = b[bytes.IndexByte(b, '\n')+1:]
+	// Modify the command in the header to include:
+	//  mkpost, our own warning, and a build tag.
+	replacement := fmt.Sprintf(`$1 | go run mkpost.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build %s,%s`, goarch, goos)
+	cgoCommandRegex := regexp.MustCompile(`(cgo -godefs .*)`)
+	b = cgoCommandRegex.ReplaceAll(b, []byte(replacement))
+
+	// gofmt
+	b, err = format.Source(b)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	os.Stdout.Write(b)
+}

vendor/golang.org/x/sys/unix/mksyscall.pl

@@ -0,0 +1,328 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# This program reads a file containing function prototypes
+# (like syscall_darwin.go) and generates system call bodies.
+# The prototypes are marked by lines beginning with "//sys"
+# and read like func declarations if //sys is replaced by func, but:
+#	* The parameter lists must give a name for each argument.
+#	  This includes return parameters.
+#	* The parameter lists must give a type for each argument:
+#	  the (x, y, z int) shorthand is not allowed.
+#	* If the return parameter is an error number, it must be named errno.
+
+# A line beginning with //sysnb is like //sys, except that the
+# goroutine will not be suspended during the execution of the system
+# call.  This must only be used for system calls which can never
+# block, as otherwise the system call could cause all goroutines to
+# hang.
+
+use strict;
+
+my $cmdline = "mksyscall.pl " . join(' ', @ARGV);
+my $errors = 0;
+my $_32bit = "";
+my $plan9 = 0;
+my $openbsd = 0;
+my $netbsd = 0;
+my $dragonfly = 0;
+my $arm = 0; # 64-bit value should use (even, odd)-pair
+my $tags = "";  # build tags
+
+if($ARGV[0] eq "-b32") {
+	$_32bit = "big-endian";
+	shift;
+} elsif($ARGV[0] eq "-l32") {
+	$_32bit = "little-endian";
+	shift;
+}
+if($ARGV[0] eq "-plan9") {
+	$plan9 = 1;
+	shift;
+}
+if($ARGV[0] eq "-openbsd") {
+	$openbsd = 1;
+	shift;
+}
+if($ARGV[0] eq "-netbsd") {
+	$netbsd = 1;
+	shift;
+}
+if($ARGV[0] eq "-dragonfly") {
+	$dragonfly = 1;
+	shift;
+}
+if($ARGV[0] eq "-arm") {
+	$arm = 1;
+	shift;
+}
+if($ARGV[0] eq "-tags") {
+	shift;
+	$tags = $ARGV[0];
+	shift;
+}
+
+if($ARGV[0] =~ /^-/) {
+	print STDERR "usage: mksyscall.pl [-b32 | -l32] [-tags x,y] [file ...]\n";
+	exit 1;
+}
+
+# Check that we are using the new build system if we should
+if($ENV{'GOOS'} eq "linux" && $ENV{'GOARCH'} ne "sparc64") {
+	if($ENV{'GOLANG_SYS_BUILD'} ne "docker") {
+		print STDERR "In the new build system, mksyscall should not be called directly.\n";
+		print STDERR "See README.md\n";
+		exit 1;
+	}
+}
+
+
+sub parseparamlist($) {
+	my ($list) = @_;
+	$list =~ s/^\s*//;
+	$list =~ s/\s*$//;
+	if($list eq "") {
+		return ();
+	}
+	return split(/\s*,\s*/, $list);
+}
+
+sub parseparam($) {
+	my ($p) = @_;
+	if($p !~ /^(\S*) (\S*)$/) {
+		print STDERR "$ARGV:$.: malformed parameter: $p\n";
+		$errors = 1;
+		return ("xx", "int");
+	}
+	return ($1, $2);
+}
+
+my $text = "";
+while(<>) {
+	chomp;
+	s/\s+/ /g;
+	s/^\s+//;
+	s/\s+$//;
+	my $nonblock = /^\/\/sysnb /;
+	next if !/^\/\/sys / && !$nonblock;
+
+	# Line must be of the form
+	#	func Open(path string, mode int, perm int) (fd int, errno error)
+	# Split into name, in params, out params.
+	if(!/^\/\/sys(nb)? (\w+)\(([^()]*)\)\s*(?:\(([^()]+)\))?\s*(?:=\s*((?i)SYS_[A-Z0-9_]+))?$/) {
+		print STDERR "$ARGV:$.: malformed //sys declaration\n";
+		$errors = 1;
+		next;
+	}
+	my ($func, $in, $out, $sysname) = ($2, $3, $4, $5);
+
+	# Split argument lists on comma.
+	my @in = parseparamlist($in);
+	my @out = parseparamlist($out);
+
+	# Try in vain to keep people from editing this file.
+	# The theory is that they jump into the middle of the file
+	# without reading the header.
+	$text .= "// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n\n";
+
+	# Go function header.
+	my $out_decl = @out ? sprintf(" (%s)", join(', ', @out)) : "";
+	$text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out_decl;
+
+	# Check if err return available
+	my $errvar = "";
+	foreach my $p (@out) {
+		my ($name, $type) = parseparam($p);
+		if($type eq "error") {
+			$errvar = $name;
+			last;
+		}
+	}
+
+	# Prepare arguments to Syscall.
+	my @args = ();
+	my $n = 0;
+	foreach my $p (@in) {
+		my ($name, $type) = parseparam($p);
+		if($type =~ /^\*/) {
+			push @args, "uintptr(unsafe.Pointer($name))";
+		} elsif($type eq "string" && $errvar ne "") {
+			$text .= "\tvar _p$n *byte\n";
+			$text .= "\t_p$n, $errvar = BytePtrFromString($name)\n";
+			$text .= "\tif $errvar != nil {\n\t\treturn\n\t}\n";
+			push @args, "uintptr(unsafe.Pointer(_p$n))";
+			$n++;
+		} elsif($type eq "string") {
+			print STDERR "$ARGV:$.: $func uses string arguments, but has no error return\n";
+			$text .= "\tvar _p$n *byte\n";
+			$text .= "\t_p$n, _ = BytePtrFromString($name)\n";
+			push @args, "uintptr(unsafe.Pointer(_p$n))";
+			$n++;
+		} elsif($type =~ /^\[\](.*)/) {
+			# Convert slice into pointer, length.
+			# Have to be careful not to take address of &a[0] if len == 0:
+			# pass dummy pointer in that case.
+			# Used to pass nil, but some OSes or simulators reject write(fd, nil, 0).
+			$text .= "\tvar _p$n unsafe.Pointer\n";
+			$text .= "\tif len($name) > 0 {\n\t\t_p$n = unsafe.Pointer(\&${name}[0])\n\t}";
+			$text .= " else {\n\t\t_p$n = unsafe.Pointer(&_zero)\n\t}";
+			$text .= "\n";
+			push @args, "uintptr(_p$n)", "uintptr(len($name))";
+			$n++;
+		} elsif($type eq "int64" && ($openbsd || $netbsd)) {
+			push @args, "0";
+			if($_32bit eq "big-endian") {
+				push @args, "uintptr($name>>32)", "uintptr($name)";
+			} elsif($_32bit eq "little-endian") {
+				push @args, "uintptr($name)", "uintptr($name>>32)";
+			} else {
+				push @args, "uintptr($name)";
+			}
+		} elsif($type eq "int64" && $dragonfly) {
+			if ($func !~ /^extp(read|write)/i) {
+				push @args, "0";
+			}
+			if($_32bit eq "big-endian") {
+				push @args, "uintptr($name>>32)", "uintptr($name)";
+			} elsif($_32bit eq "little-endian") {
+				push @args, "uintptr($name)", "uintptr($name>>32)";
+			} else {
+				push @args, "uintptr($name)";
+			}
+		} elsif($type eq "int64" && $_32bit ne "") {
+			if(@args % 2 && $arm) {
+				# arm abi specifies 64-bit argument uses
+				# (even, odd) pair
+				push @args, "0"
+			}
+			if($_32bit eq "big-endian") {
+				push @args, "uintptr($name>>32)", "uintptr($name)";
+			} else {
+				push @args, "uintptr($name)", "uintptr($name>>32)";
+			}
+		} else {
+			push @args, "uintptr($name)";
+		}
+	}
+
+	# Determine which form to use; pad args with zeros.
+	my $asm = "Syscall";
+	if ($nonblock) {
+		$asm = "RawSyscall";
+	}
+	if(@args <= 3) {
+		while(@args < 3) {
+			push @args, "0";
+		}
+	} elsif(@args <= 6) {
+		$asm .= "6";
+		while(@args < 6) {
+			push @args, "0";
+		}
+	} elsif(@args <= 9) {
+		$asm .= "9";
+		while(@args < 9) {
+			push @args, "0";
+		}
+	} else {
+		print STDERR "$ARGV:$.: too many arguments to system call\n";
+	}
+
+	# System call number.
+	if($sysname eq "") {
+		$sysname = "SYS_$func";
+		$sysname =~ s/([a-z])([A-Z])/${1}_$2/g;	# turn FooBar into Foo_Bar
+		$sysname =~ y/a-z/A-Z/;
+	}
+
+	# Actual call.
+	my $args = join(', ', @args);
+	my $call = "$asm($sysname, $args)";
+
+	# Assign return values.
+	my $body = "";
+	my @ret = ("_", "_", "_");
+	my $do_errno = 0;
+	for(my $i=0; $i<@out; $i++) {
+		my $p = $out[$i];
+		my ($name, $type) = parseparam($p);
+		my $reg = "";
+		if($name eq "err" && !$plan9) {
+			$reg = "e1";
+			$ret[2] = $reg;
+			$do_errno = 1;
+		} elsif($name eq "err" && $plan9) {
+			$ret[0] = "r0";
+			$ret[2] = "e1";
+			next;
+		} else {
+			$reg = sprintf("r%d", $i);
+			$ret[$i] = $reg;
+		}
+		if($type eq "bool") {
+			$reg = "$reg != 0";
+		}
+		if($type eq "int64" && $_32bit ne "") {
+			# 64-bit number in r1:r0 or r0:r1.
+			if($i+2 > @out) {
+				print STDERR "$ARGV:$.: not enough registers for int64 return\n";
+			}
+			if($_32bit eq "big-endian") {
+				$reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i, $i+1);
+			} else {
+				$reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i+1, $i);
+			}
+			$ret[$i] = sprintf("r%d", $i);
+			$ret[$i+1] = sprintf("r%d", $i+1);
+		}
+		if($reg ne "e1" || $plan9) {
+			$body .= "\t$name = $type($reg)\n";
+		}
+	}
+	if ($ret[0] eq "_" && $ret[1] eq "_" && $ret[2] eq "_") {
+		$text .= "\t$call\n";
+	} else {
+		$text .= "\t$ret[0], $ret[1], $ret[2] := $call\n";
+	}
+	$text .= $body;
+
+	if ($plan9 && $ret[2] eq "e1") {
+		$text .= "\tif int32(r0) == -1 {\n";
+		$text .= "\t\terr = e1\n";
+		$text .= "\t}\n";
+	} elsif ($do_errno) {
+		$text .= "\tif e1 != 0 {\n";
+		$text .= "\t\terr = errnoErr(e1)\n";
+		$text .= "\t}\n";
+	}
+	$text .= "\treturn\n";
+	$text .= "}\n\n";
+}
+
+chomp $text;
+chomp $text;
+
+if($errors) {
+	exit 1;
+}
+
+print <<EOF;
+// $cmdline
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $tags
+
+package unix
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+var _ syscall.Errno
+
+$text
+EOF
+exit 0;

vendor/golang.org/x/sys/unix/mksyscall_solaris.pl

@@ -0,0 +1,289 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# This program reads a file containing function prototypes
+# (like syscall_solaris.go) and generates system call bodies.
+# The prototypes are marked by lines beginning with "//sys"
+# and read like func declarations if //sys is replaced by func, but:
+#	* The parameter lists must give a name for each argument.
+#	  This includes return parameters.
+#	* The parameter lists must give a type for each argument:
+#	  the (x, y, z int) shorthand is not allowed.
+#	* If the return parameter is an error number, it must be named err.
+#	* If go func name needs to be different than its libc name,
+#	* or the function is not in libc, name could be specified
+#	* at the end, after "=" sign, like
+#	  //sys getsockopt(s int, level int, name int, val uintptr, vallen *_Socklen) (err error) = libsocket.getsockopt
+
+use strict;
+
+my $cmdline = "mksyscall_solaris.pl " . join(' ', @ARGV);
+my $errors = 0;
+my $_32bit = "";
+my $tags = "";  # build tags
+
+binmode STDOUT;
+
+if($ARGV[0] eq "-b32") {
+	$_32bit = "big-endian";
+	shift;
+} elsif($ARGV[0] eq "-l32") {
+	$_32bit = "little-endian";
+	shift;
+}
+if($ARGV[0] eq "-tags") {
+	shift;
+	$tags = $ARGV[0];
+	shift;
+}
+
+if($ARGV[0] =~ /^-/) {
+	print STDERR "usage: mksyscall_solaris.pl [-b32 | -l32] [-tags x,y] [file ...]\n";
+	exit 1;
+}
+
+sub parseparamlist($) {
+	my ($list) = @_;
+	$list =~ s/^\s*//;
+	$list =~ s/\s*$//;
+	if($list eq "") {
+		return ();
+	}
+	return split(/\s*,\s*/, $list);
+}
+
+sub parseparam($) {
+	my ($p) = @_;
+	if($p !~ /^(\S*) (\S*)$/) {
+		print STDERR "$ARGV:$.: malformed parameter: $p\n";
+		$errors = 1;
+		return ("xx", "int");
+	}
+	return ($1, $2);
+}
+
+my $package = "";
+my $text = "";
+my $dynimports = "";
+my $linknames = "";
+my @vars = ();
+while(<>) {
+	chomp;
+	s/\s+/ /g;
+	s/^\s+//;
+	s/\s+$//;
+	$package = $1 if !$package && /^package (\S+)$/;
+	my $nonblock = /^\/\/sysnb /;
+	next if !/^\/\/sys / && !$nonblock;
+
+	# Line must be of the form
+	#	func Open(path string, mode int, perm int) (fd int, err error)
+	# Split into name, in params, out params.
+	if(!/^\/\/sys(nb)? (\w+)\(([^()]*)\)\s*(?:\(([^()]+)\))?\s*(?:=\s*(?:(\w*)\.)?(\w*))?$/) {
+		print STDERR "$ARGV:$.: malformed //sys declaration\n";
+		$errors = 1;
+		next;
+	}
+	my ($nb, $func, $in, $out, $modname, $sysname) = ($1, $2, $3, $4, $5, $6);
+
+	# Split argument lists on comma.
+	my @in = parseparamlist($in);
+	my @out = parseparamlist($out);
+
+	# So file name.
+	if($modname eq "") {
+		$modname = "libc";
+	}
+
+	# System call name.
+	if($sysname eq "") {
+		$sysname = "$func";
+	}
+
+	# System call pointer variable name.
+	my $sysvarname = "proc$sysname";
+
+	my $strconvfunc = "BytePtrFromString";
+	my $strconvtype = "*byte";
+
+	$sysname =~ y/A-Z/a-z/; # All libc functions are lowercase.
+
+	# Runtime import of function to allow cross-platform builds.
+	$dynimports .= "//go:cgo_import_dynamic libc_${sysname} ${sysname} \"$modname.so\"\n";
+	# Link symbol to proc address variable.
+	$linknames .= "//go:linkname ${sysvarname} libc_${sysname}\n";
+	# Library proc address variable.
+	push @vars, $sysvarname;
+
+	# Go function header.
+	$out = join(', ', @out);
+	if($out ne "") {
+		$out = " ($out)";
+	}
+	if($text ne "") {
+		$text .= "\n"
+	}
+	$text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out;
+
+	# Check if err return available
+	my $errvar = "";
+	foreach my $p (@out) {
+		my ($name, $type) = parseparam($p);
+		if($type eq "error") {
+			$errvar = $name;
+			last;
+		}
+	}
+
+	# Prepare arguments to Syscall.
+	my @args = ();
+	my $n = 0;
+	foreach my $p (@in) {
+		my ($name, $type) = parseparam($p);
+		if($type =~ /^\*/) {
+			push @args, "uintptr(unsafe.Pointer($name))";
+		} elsif($type eq "string" && $errvar ne "") {
+			$text .= "\tvar _p$n $strconvtype\n";
+			$text .= "\t_p$n, $errvar = $strconvfunc($name)\n";
+			$text .= "\tif $errvar != nil {\n\t\treturn\n\t}\n";
+			push @args, "uintptr(unsafe.Pointer(_p$n))";
+			$n++;
+		} elsif($type eq "string") {
+			print STDERR "$ARGV:$.: $func uses string arguments, but has no error return\n";
+			$text .= "\tvar _p$n $strconvtype\n";
+			$text .= "\t_p$n, _ = $strconvfunc($name)\n";
+			push @args, "uintptr(unsafe.Pointer(_p$n))";
+			$n++;
+		} elsif($type =~ /^\[\](.*)/) {
+			# Convert slice into pointer, length.
+			# Have to be careful not to take address of &a[0] if len == 0:
+			# pass nil in that case.
+			$text .= "\tvar _p$n *$1\n";
+			$text .= "\tif len($name) > 0 {\n\t\t_p$n = \&$name\[0]\n\t}\n";
+			push @args, "uintptr(unsafe.Pointer(_p$n))", "uintptr(len($name))";
+			$n++;
+		} elsif($type eq "int64" && $_32bit ne "") {
+			if($_32bit eq "big-endian") {
+				push @args, "uintptr($name >> 32)", "uintptr($name)";
+			} else {
+				push @args, "uintptr($name)", "uintptr($name >> 32)";
+			}
+		} elsif($type eq "bool") {
+ 			$text .= "\tvar _p$n uint32\n";
+			$text .= "\tif $name {\n\t\t_p$n = 1\n\t} else {\n\t\t_p$n = 0\n\t}\n";
+			push @args, "uintptr(_p$n)";
+			$n++;
+		} else {
+			push @args, "uintptr($name)";
+		}
+	}
+	my $nargs = @args;
+
+	# Determine which form to use; pad args with zeros.
+	my $asm = "sysvicall6";
+	if ($nonblock) {
+		$asm = "rawSysvicall6";
+	}
+	if(@args <= 6) {
+		while(@args < 6) {
+			push @args, "0";
+		}
+	} else {
+		print STDERR "$ARGV:$.: too many arguments to system call\n";
+	}
+
+	# Actual call.
+	my $args = join(', ', @args);
+	my $call = "$asm(uintptr(unsafe.Pointer(&$sysvarname)), $nargs, $args)";
+
+	# Assign return values.
+	my $body = "";
+	my $failexpr = "";
+	my @ret = ("_", "_", "_");
+	my @pout= ();
+	my $do_errno = 0;
+	for(my $i=0; $i<@out; $i++) {
+		my $p = $out[$i];
+		my ($name, $type) = parseparam($p);
+		my $reg = "";
+		if($name eq "err") {
+			$reg = "e1";
+			$ret[2] = $reg;
+			$do_errno = 1;
+		} else {
+			$reg = sprintf("r%d", $i);
+			$ret[$i] = $reg;
+		}
+		if($type eq "bool") {
+			$reg = "$reg != 0";
+		}
+		if($type eq "int64" && $_32bit ne "") {
+			# 64-bit number in r1:r0 or r0:r1.
+			if($i+2 > @out) {
+				print STDERR "$ARGV:$.: not enough registers for int64 return\n";
+			}
+			if($_32bit eq "big-endian") {
+				$reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i, $i+1);
+			} else {
+				$reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i+1, $i);
+			}
+			$ret[$i] = sprintf("r%d", $i);
+			$ret[$i+1] = sprintf("r%d", $i+1);
+		}
+		if($reg ne "e1") {
+			$body .= "\t$name = $type($reg)\n";
+		}
+	}
+	if ($ret[0] eq "_" && $ret[1] eq "_" && $ret[2] eq "_") {
+		$text .= "\t$call\n";
+	} else {
+		$text .= "\t$ret[0], $ret[1], $ret[2] := $call\n";
+	}
+	$text .= $body;
+
+	if ($do_errno) {
+		$text .= "\tif e1 != 0 {\n";
+		$text .= "\t\terr = e1\n";
+		$text .= "\t}\n";
+	}
+	$text .= "\treturn\n";
+	$text .= "}\n";
+}
+
+if($errors) {
+	exit 1;
+}
+
+print <<EOF;
+// $cmdline
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $tags
+
+package $package
+
+import (
+	"syscall"
+	"unsafe"
+)
+EOF
+
+print "import \"golang.org/x/sys/unix\"\n" if $package ne "unix";
+
+my $vardecls = "\t" . join(",\n\t", @vars);
+$vardecls .= " syscallFunc";
+
+chomp($_=<<EOF);
+
+$dynimports
+$linknames
+var (
+$vardecls
+)
+
+$text
+EOF
+print $_;
+exit 0;

vendor/golang.org/x/sys/unix/mksysctl_openbsd.pl

@@ -0,0 +1,264 @@
+#!/usr/bin/env perl
+
+# Copyright 2011 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+#
+# Parse the header files for OpenBSD and generate a Go usable sysctl MIB.
+#
+# Build a MIB with each entry being an array containing the level, type and
+# a hash that will contain additional entries if the current entry is a node.
+# We then walk this MIB and create a flattened sysctl name to OID hash.
+#
+
+use strict;
+
+if($ENV{'GOARCH'} eq "" || $ENV{'GOOS'} eq "") {
+	print STDERR "GOARCH or GOOS not defined in environment\n";
+	exit 1;
+}
+
+my $debug = 0;
+my %ctls = ();
+
+my @headers = qw (
+	sys/sysctl.h
+	sys/socket.h
+	sys/tty.h
+	sys/malloc.h
+	sys/mount.h
+	sys/namei.h
+	sys/sem.h
+	sys/shm.h
+	sys/vmmeter.h
+	uvm/uvm_param.h
+	uvm/uvm_swap_encrypt.h
+	ddb/db_var.h
+	net/if.h
+	net/if_pfsync.h
+	net/pipex.h
+	netinet/in.h
+	netinet/icmp_var.h
+	netinet/igmp_var.h
+	netinet/ip_ah.h
+	netinet/ip_carp.h
+	netinet/ip_divert.h
+	netinet/ip_esp.h
+	netinet/ip_ether.h
+	netinet/ip_gre.h
+	netinet/ip_ipcomp.h
+	netinet/ip_ipip.h
+	netinet/pim_var.h
+	netinet/tcp_var.h
+	netinet/udp_var.h
+	netinet6/in6.h
+	netinet6/ip6_divert.h
+	netinet6/pim6_var.h
+	netinet/icmp6.h
+	netmpls/mpls.h
+);
+
+my @ctls = qw (
+	kern
+	vm
+	fs
+	net
+	#debug				# Special handling required
+	hw
+	#machdep			# Arch specific
+	user
+	ddb
+	#vfs				# Special handling required
+	fs.posix
+	kern.forkstat
+	kern.intrcnt
+	kern.malloc
+	kern.nchstats
+	kern.seminfo
+	kern.shminfo
+	kern.timecounter
+	kern.tty
+	kern.watchdog
+	net.bpf
+	net.ifq
+	net.inet
+	net.inet.ah
+	net.inet.carp
+	net.inet.divert
+	net.inet.esp
+	net.inet.etherip
+	net.inet.gre
+	net.inet.icmp
+	net.inet.igmp
+	net.inet.ip
+	net.inet.ip.ifq
+	net.inet.ipcomp
+	net.inet.ipip
+	net.inet.mobileip
+	net.inet.pfsync
+	net.inet.pim
+	net.inet.tcp
+	net.inet.udp
+	net.inet6
+	net.inet6.divert
+	net.inet6.ip6
+	net.inet6.icmp6
+	net.inet6.pim6
+	net.inet6.tcp6
+	net.inet6.udp6
+	net.mpls
+	net.mpls.ifq
+	net.key
+	net.pflow
+	net.pfsync
+	net.pipex
+	net.rt
+	vm.swapencrypt
+	#vfsgenctl			# Special handling required
+);
+
+# Node name "fixups"
+my %ctl_map = (
+	"ipproto" => "net.inet",
+	"net.inet.ipproto" => "net.inet",
+	"net.inet6.ipv6proto" => "net.inet6",
+	"net.inet6.ipv6" => "net.inet6.ip6",
+	"net.inet.icmpv6" => "net.inet6.icmp6",
+	"net.inet6.divert6" => "net.inet6.divert",
+	"net.inet6.tcp6" => "net.inet.tcp",
+	"net.inet6.udp6" => "net.inet.udp",
+	"mpls" => "net.mpls",
+	"swpenc" => "vm.swapencrypt"
+);
+
+# Node mappings
+my %node_map = (
+	"net.inet.ip.ifq" => "net.ifq",
+	"net.inet.pfsync" => "net.pfsync",
+	"net.mpls.ifq" => "net.ifq"
+);
+
+my $ctlname;
+my %mib = ();
+my %sysctl = ();
+my $node;
+
+sub debug() {
+	print STDERR "$_[0]\n" if $debug;
+}
+
+# Walk the MIB and build a sysctl name to OID mapping.
+sub build_sysctl() {
+	my ($node, $name, $oid) = @_;
+	my %node = %{$node};
+	my @oid = @{$oid};
+
+	foreach my $key (sort keys %node) {
+		my @node = @{$node{$key}};
+		my $nodename = $name.($name ne '' ? '.' : '').$key;
+		my @nodeoid = (@oid, $node[0]);
+		if ($node[1] eq 'CTLTYPE_NODE') {
+			if (exists $node_map{$nodename}) {
+				$node = \%mib;
+				$ctlname = $node_map{$nodename};
+				foreach my $part (split /\./, $ctlname) {
+					$node = \%{@{$$node{$part}}[2]};
+				}
+			} else {
+				$node = $node[2];
+			}
+			&build_sysctl($node, $nodename, \@nodeoid);
+		} elsif ($node[1] ne '') {
+			$sysctl{$nodename} = \@nodeoid;
+		}
+	}
+}
+
+foreach my $ctl (@ctls) {
+	$ctls{$ctl} = $ctl;
+}
+
+# Build MIB
+foreach my $header (@headers) {
+	&debug("Processing $header...");
+	open HEADER, "/usr/include/$header" ||
+	    print STDERR "Failed to open $header\n";
+	while (<HEADER>) {
+		if ($_ =~ /^#define\s+(CTL_NAMES)\s+{/ ||
+		    $_ =~ /^#define\s+(CTL_(.*)_NAMES)\s+{/ ||
+		    $_ =~ /^#define\s+((.*)CTL_NAMES)\s+{/) {
+			if ($1 eq 'CTL_NAMES') {
+				# Top level.
+				$node = \%mib;
+			} else {
+				# Node.
+				my $nodename = lc($2);
+				if ($header =~ /^netinet\//) {
+					$ctlname = "net.inet.$nodename";
+				} elsif ($header =~ /^netinet6\//) {
+					$ctlname = "net.inet6.$nodename";
+				} elsif ($header =~ /^net\//) {
+					$ctlname = "net.$nodename";
+				} else {
+					$ctlname = "$nodename";
+					$ctlname =~ s/^(fs|net|kern)_/$1\./;
+				}
+				if (exists $ctl_map{$ctlname}) {
+					$ctlname = $ctl_map{$ctlname};
+				}
+				if (not exists $ctls{$ctlname}) {
+					&debug("Ignoring $ctlname...");
+					next;
+				}
+
+				# Walk down from the top of the MIB.
+				$node = \%mib;
+				foreach my $part (split /\./, $ctlname) {
+					if (not exists $$node{$part}) {
+						&debug("Missing node $part");
+						$$node{$part} = [ 0, '', {} ];
+					}
+					$node = \%{@{$$node{$part}}[2]};
+				}
+			}
+
+			# Populate current node with entries.
+			my $i = -1;
+			while (defined($_) && $_ !~ /^}/) {
+				$_ = <HEADER>;
+				$i++ if $_ =~ /{.*}/;
+				next if $_ !~ /{\s+"(\w+)",\s+(CTLTYPE_[A-Z]+)\s+}/;
+				$$node{$1} = [ $i, $2, {} ];
+			}
+		}
+	}
+	close HEADER;
+}
+
+&build_sysctl(\%mib, "", []);
+
+print <<EOF;
+// mksysctl_openbsd.pl
+// MACHINE GENERATED BY THE ABOVE COMMAND; DO NOT EDIT
+
+// +build $ENV{'GOARCH'},$ENV{'GOOS'}
+
+package unix;
+
+type mibentry struct {
+	ctlname string
+	ctloid []_C_int
+}
+
+var sysctlMib = []mibentry {
+EOF
+
+foreach my $name (sort keys %sysctl) {
+	my @oid = @{$sysctl{$name}};
+	print "\t{ \"$name\", []_C_int{ ", join(', ', @oid), " } }, \n";
+}
+
+print <<EOF;
+}
+EOF

vendor/golang.org/x/sys/unix/mksysnum_darwin.pl

@@ -0,0 +1,39 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+#
+# Generate system call table for Darwin from sys/syscall.h
+
+use strict;
+
+if($ENV{'GOARCH'} eq "" || $ENV{'GOOS'} eq "") {
+	print STDERR "GOARCH or GOOS not defined in environment\n";
+	exit 1;
+}
+
+my $command = "mksysnum_darwin.pl " . join(' ', @ARGV);
+
+print <<EOF;
+// $command
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $ENV{'GOARCH'},$ENV{'GOOS'}
+
+package unix
+
+const (
+EOF
+
+while(<>){
+	if(/^#define\s+SYS_(\w+)\s+([0-9]+)/){
+		my $name = $1;
+		my $num = $2;
+		$name =~ y/a-z/A-Z/;
+		print "	SYS_$name = $num;"
+	}
+}
+
+print <<EOF;
+)
+EOF

vendor/golang.org/x/sys/unix/mksysnum_dragonfly.pl

@@ -0,0 +1,50 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+#
+# Generate system call table for DragonFly from master list
+# (for example, /usr/src/sys/kern/syscalls.master).
+
+use strict;
+
+if($ENV{'GOARCH'} eq "" || $ENV{'GOOS'} eq "") {
+	print STDERR "GOARCH or GOOS not defined in environment\n";
+	exit 1;
+}
+
+my $command = "mksysnum_dragonfly.pl " . join(' ', @ARGV);
+
+print <<EOF;
+// $command
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $ENV{'GOARCH'},$ENV{'GOOS'}
+
+package unix
+
+const (
+EOF
+
+while(<>){
+	if(/^([0-9]+)\s+STD\s+({ \S+\s+(\w+).*)$/){
+		my $num = $1;
+		my $proto = $2;
+		my $name = "SYS_$3";
+		$name =~ y/a-z/A-Z/;
+
+		# There are multiple entries for enosys and nosys, so comment them out.
+		if($name =~ /^SYS_E?NOSYS$/){
+			$name = "// $name";
+		}
+		if($name eq 'SYS_SYS_EXIT'){
+			$name = 'SYS_EXIT';
+		}
+
+		print "	$name = $num;  // $proto\n";
+	}
+}
+
+print <<EOF;
+)
+EOF

vendor/golang.org/x/sys/unix/mksysnum_freebsd.pl

@@ -0,0 +1,50 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+#
+# Generate system call table for FreeBSD from master list
+# (for example, /usr/src/sys/kern/syscalls.master).
+
+use strict;
+
+if($ENV{'GOARCH'} eq "" || $ENV{'GOOS'} eq "") {
+	print STDERR "GOARCH or GOOS not defined in environment\n";
+	exit 1;
+}
+
+my $command = "mksysnum_freebsd.pl " . join(' ', @ARGV);
+
+print <<EOF;
+// $command
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $ENV{'GOARCH'},$ENV{'GOOS'}
+
+package unix
+
+const (
+EOF
+
+while(<>){
+	if(/^([0-9]+)\s+\S+\s+STD\s+({ \S+\s+(\w+).*)$/){
+		my $num = $1;
+		my $proto = $2;
+		my $name = "SYS_$3";
+		$name =~ y/a-z/A-Z/;
+
+		# There are multiple entries for enosys and nosys, so comment them out.
+		if($name =~ /^SYS_E?NOSYS$/){
+			$name = "// $name";
+		}
+		if($name eq 'SYS_SYS_EXIT'){
+			$name = 'SYS_EXIT';
+		}
+
+		print "	$name = $num;  // $proto\n";
+	}
+}
+
+print <<EOF;
+)
+EOF

vendor/golang.org/x/sys/unix/mksysnum_netbsd.pl

@@ -0,0 +1,58 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+#
+# Generate system call table for OpenBSD from master list
+# (for example, /usr/src/sys/kern/syscalls.master).
+
+use strict;
+
+if($ENV{'GOARCH'} eq "" || $ENV{'GOOS'} eq "") {
+	print STDERR "GOARCH or GOOS not defined in environment\n";
+	exit 1;
+}
+
+my $command = "mksysnum_netbsd.pl " . join(' ', @ARGV);
+
+print <<EOF;
+// $command
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $ENV{'GOARCH'},$ENV{'GOOS'}
+
+package unix
+
+const (
+EOF
+
+my $line = '';
+while(<>){
+	if($line =~ /^(.*)\\$/) {
+		# Handle continuation
+		$line = $1;
+		$_ =~ s/^\s+//;
+		$line .= $_;
+	} else {
+		# New line
+		$line = $_;
+	}
+	next if $line =~ /\\$/;
+	if($line =~ /^([0-9]+)\s+((STD)|(NOERR))\s+(RUMP\s+)?({\s+\S+\s*\*?\s*\|(\S+)\|(\S*)\|(\w+).*\s+})(\s+(\S+))?$/) {
+		my $num = $1;
+		my $proto = $6;
+		my $compat = $8;
+		my $name = "$7_$9";
+
+		$name = "$7_$11" if $11 ne '';
+		$name =~ y/a-z/A-Z/;
+
+		if($compat eq '' || $compat eq '13' || $compat eq '30' || $compat eq '50') {
+			print "	$name = $num;  // $proto\n";
+		}
+	}
+}
+
+print <<EOF;
+)
+EOF

vendor/golang.org/x/sys/unix/mksysnum_openbsd.pl

@@ -0,0 +1,50 @@
+#!/usr/bin/env perl
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+#
+# Generate system call table for OpenBSD from master list
+# (for example, /usr/src/sys/kern/syscalls.master).
+
+use strict;
+
+if($ENV{'GOARCH'} eq "" || $ENV{'GOOS'} eq "") {
+	print STDERR "GOARCH or GOOS not defined in environment\n";
+	exit 1;
+}
+
+my $command = "mksysnum_openbsd.pl " . join(' ', @ARGV);
+
+print <<EOF;
+// $command
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build $ENV{'GOARCH'},$ENV{'GOOS'}
+
+package unix
+
+const (
+EOF
+
+while(<>){
+	if(/^([0-9]+)\s+STD\s+(NOLOCK\s+)?({ \S+\s+\*?(\w+).*)$/){
+		my $num = $1;
+		my $proto = $3;
+		my $name = $4;
+		$name =~ y/a-z/A-Z/;
+
+		# There are multiple entries for enosys and nosys, so comment them out.
+		if($name =~ /^SYS_E?NOSYS$/){
+			$name = "// $name";
+		}
+		if($name eq 'SYS_SYS_EXIT'){
+			$name = 'SYS_EXIT';
+		}
+
+		print "	$name = $num;  // $proto\n";
+	}
+}
+
+print <<EOF;
+)
+EOF

vendor/golang.org/x/sys/unix/openbsd_pledge.go

@@ -0,0 +1,38 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build openbsd
+// +build 386 amd64 arm
+
+package unix
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+const (
+	SYS_PLEDGE = 108
+)
+
+// Pledge implements the pledge syscall. For more information see pledge(2).
+func Pledge(promises string, paths []string) error {
+	promisesPtr, err := syscall.BytePtrFromString(promises)
+	if err != nil {
+		return err
+	}
+	promisesUnsafe, pathsUnsafe := unsafe.Pointer(promisesPtr), unsafe.Pointer(nil)
+	if paths != nil {
+		var pathsPtr []*byte
+		if pathsPtr, err = syscall.SlicePtrFromStrings(paths); err != nil {
+			return err
+		}
+		pathsUnsafe = unsafe.Pointer(&pathsPtr[0])
+	}
+	_, _, e := syscall.Syscall(SYS_PLEDGE, uintptr(promisesUnsafe), uintptr(pathsUnsafe), 0)
+	if e != 0 {
+		return e
+	}
+	return nil
+}

vendor/golang.org/x/sys/unix/pagesize_unix.go

@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+// For Unix, get the pagesize from the runtime.
+
+package unix
+
+import "syscall"
+
+func Getpagesize() int {
+	return syscall.Getpagesize()
+}

vendor/golang.org/x/sys/unix/race.go

@@ -0,0 +1,30 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin,race linux,race freebsd,race
+
+package unix
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+const raceenabled = true
+
+func raceAcquire(addr unsafe.Pointer) {
+	runtime.RaceAcquire(addr)
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+	runtime.RaceReleaseMerge(addr)
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+	runtime.RaceReadRange(addr, len)
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+	runtime.RaceWriteRange(addr, len)
+}