Merge branch 'master' into slack

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## Breaking Changes
 
+- [#231](https://github.com/pusher/oauth2_proxy/pull/231) Rework GitLab provider (@Overv)
+  - This PR changes the configuration options for the GitLab provider to use
+  a self-hosted instance. You now need to specify a `-oidc-issuer-url` rather than
+  explicit `-login-url`, `-redeem-url` and `-validate-url` parameters.
+
 - [#186](https://github.com/pusher/oauth2_proxy/pull/186) Make config consistent
   - This PR changes configuration options so that all flags have a config counterpart
   of the same name but with underscores (`_`) in place of hyphens (`-`).
@@ -32,6 +37,7 @@
 ## Changes since v3.2.0
 
 - [#224](https://github.com/pusher/oauth2_proxy/pull/224) Check Google group membership using hasMember to support nested groups and external users (@jpalpant)
+- [#231](https://github.com/pusher/oauth2_proxy/pull/231) Add optional group membership and email domain checks to the GitLab provider (@Overv)
 - [#178](https://github.com/pusher/outh2_proxy/pull/178) Add Silence Ping Logging and Exclude Logging Paths flags (@kskewes)
 - [#209](https://github.com/pusher/outh2_proxy/pull/209) Improve docker build caching of layers (@dekimsey)
 - [#186](https://github.com/pusher/oauth2_proxy/pull/186) Make config consistent (@JoelSpeed)

docs/2_auth.md

@@ -103,13 +103,15 @@ If you are using GitHub enterprise, make sure you set the following to the appro
 
 ### GitLab Auth Provider
 
-Whether you are using GitLab.com or self-hosting GitLab, follow [these steps to add an application](http://doc.gitlab.com/ce/integration/oauth_provider.html)
+Whether you are using GitLab.com or self-hosting GitLab, follow [these steps to add an application](http://doc.gitlab.com/ce/integration/oauth_provider.html). Make sure to enable at least the `openid`, `profile` and `email` scopes.
+
+Restricting by group membership is possible with the following option:
+
+    -gitlab-group="": restrict logins to members of any of these groups (slug), separated by a comma
 
 If you are using self-hosted GitLab, make sure you set the following to the appropriate URL:
 
-    -login-url="<your gitlab url>/oauth/authorize"
-    -redeem-url="<your gitlab url>/oauth/token"
-    -validate-url="<your gitlab url>/api/v4/user"
+    -oidc-issuer-url="<your gitlab url>"
 
 ### LinkedIn Auth Provider
 

docs/configuration/configuration.md

@@ -49,6 +49,7 @@ Usage of oauth2_proxy:
   -gcp-healthchecks: will enable /liveness_check, /readiness_check, and / (with the proper user-agent) endpoints that will make it work well with GCP App Engine and GKE Ingresses (default false)
   -github-org string: restrict logins to members of this organisation
   -github-team string: restrict logins to members of any of these teams (slug), separated by a comma
+  -gitlab-group string: restrict logins to members of any of these groups (slug), separated by a comma
   -google-admin-email string: the google admin to impersonate for api calls
   -google-group value: restrict logins to members of this google group (may be given multiple times).
   -google-service-account-json string: the path to the service account json credentials

main.go

@@ -57,6 +57,7 @@ func main() {
 	flagSet.String("azure-tenant", "common", "go to a tenant-specific or common (tenant-independent) endpoint.")
 	flagSet.String("github-org", "", "restrict logins to members of this organisation")
 	flagSet.String("github-team", "", "restrict logins to members of this team")
+	flagSet.String("gitlab-group", "", "restrict logins to members of this group")
 	flagSet.Var(&googleGroups, "google-group", "restrict logins to members of this google group (may be given multiple times).")
 	flagSet.String("google-admin-email", "", "the google admin to impersonate for api calls")
 	flagSet.String("google-service-account-json", "", "the path to the service account json credentials")

options.go

@@ -46,6 +46,7 @@ type Options struct {
 	WhitelistDomains         []string `flag:"whitelist-domain" cfg:"whitelist_domains" env:"OAUTH2_PROXY_WHITELIST_DOMAINS"`
 	GitHubOrg                string   `flag:"github-org" cfg:"github_org" env:"OAUTH2_PROXY_GITHUB_ORG"`
 	GitHubTeam               string   `flag:"github-team" cfg:"github_team" env:"OAUTH2_PROXY_GITHUB_TEAM"`
+	GitLabGroup              string   `flag:"gitlab-group" cfg:"gitlab_group" env:"OAUTH2_PROXY_GITLAB_GROUP"`
 	GoogleGroups             []string `flag:"google-group" cfg:"google_group" env:"OAUTH2_PROXY_GOOGLE_GROUPS"`
 	GoogleAdminEmail         string   `flag:"google-admin-email" cfg:"google_admin_email" env:"OAUTH2_PROXY_GOOGLE_ADMIN_EMAIL"`
 	GoogleServiceAccountJSON string   `flag:"google-service-account-json" cfg:"google_service_account_json" env:"OAUTH2_PROXY_GOOGLE_SERVICE_ACCOUNT_JSON"`
@@ -410,6 +411,29 @@ func parseProviderInfo(o *Options, msgs []string) []string {
 		} else {
 			p.Verifier = o.oidcVerifier
 		}
+	case *providers.GitLabProvider:
+		p.AllowUnverifiedEmail = o.InsecureOIDCAllowUnverifiedEmail
+		p.Group = o.GitLabGroup
+		p.EmailDomains = o.EmailDomains
+
+		if o.oidcVerifier != nil {
+			p.Verifier = o.oidcVerifier
+		} else {
+			// Initialize with default verifier for gitlab.com
+			ctx := context.Background()
+
+			provider, err := oidc.NewProvider(ctx, "https://gitlab.com")
+			if err != nil {
+				msgs = append(msgs, "failed to initialize oidc provider for gitlab.com")
+			} else {
+				p.Verifier = provider.Verifier(&oidc.Config{
+					ClientID: o.ClientID,
+				})
+
+				p.LoginURL, msgs = parseURL(provider.Endpoint().AuthURL, "login", msgs)
+				p.RedeemURL, msgs = parseURL(provider.Endpoint().TokenURL, "redeem", msgs)
+			}
+		}
 	case *providers.LoginGovProvider:
 		p.AcrValues = o.AcrValues
 		p.PubJWKURL, msgs = parseURL(o.PubJWKURL, "pubjwk", msgs)

providers/gitlab.go

@@ -1,62 +1,258 @@
 package providers
 
 import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
 	"net/http"
-	"net/url"
+	"strings"
+	"time"
 
+	oidc "github.com/coreos/go-oidc"
 	"github.com/pusher/oauth2_proxy/pkg/apis/sessions"
-	"github.com/pusher/oauth2_proxy/pkg/logger"
-	"github.com/pusher/oauth2_proxy/pkg/requests"
+	"golang.org/x/oauth2"
 )
 
-// GitLabProvider represents an GitLab based Identity Provider
+// GitLabProvider represents a GitLab based Identity Provider
 type GitLabProvider struct {
 	*ProviderData
+
+	Group        string
+	EmailDomains []string
+
+	Verifier             *oidc.IDTokenVerifier
+	AllowUnverifiedEmail bool
 }
 
 // NewGitLabProvider initiates a new GitLabProvider
 func NewGitLabProvider(p *ProviderData) *GitLabProvider {
 	p.ProviderName = "GitLab"
-	if p.LoginURL == nil || p.LoginURL.String() == "" {
-		p.LoginURL = &url.URL{
-			Scheme: "https",
-			Host:   "gitlab.com",
-			Path:   "/oauth/authorize",
-		}
-	}
-	if p.RedeemURL == nil || p.RedeemURL.String() == "" {
-		p.RedeemURL = &url.URL{
-			Scheme: "https",
-			Host:   "gitlab.com",
-			Path:   "/oauth/token",
-		}
-	}
-	if p.ValidateURL == nil || p.ValidateURL.String() == "" {
-		p.ValidateURL = &url.URL{
-			Scheme: "https",
-			Host:   "gitlab.com",
-			Path:   "/api/v4/user",
-		}
-	}
+
 	if p.Scope == "" {
-		p.Scope = "read_user"
+		p.Scope = "openid email"
 	}
+
 	return &GitLabProvider{ProviderData: p}
 }
 
+// Redeem exchanges the OAuth2 authentication token for an ID token
+func (p *GitLabProvider) Redeem(redirectURL, code string) (s *sessions.SessionState, err error) {
+	ctx := context.Background()
+	c := oauth2.Config{
+		ClientID:     p.ClientID,
+		ClientSecret: p.ClientSecret,
+		Endpoint: oauth2.Endpoint{
+			TokenURL: p.RedeemURL.String(),
+		},
+		RedirectURL: redirectURL,
+	}
+	token, err := c.Exchange(ctx, code)
+	if err != nil {
+		return nil, fmt.Errorf("token exchange: %v", err)
+	}
+	s, err = p.createSessionState(ctx, token)
+	if err != nil {
+		return nil, fmt.Errorf("unable to update session: %v", err)
+	}
+	return
+}
+
+// RefreshSessionIfNeeded checks if the session has expired and uses the
+// RefreshToken to fetch a new ID token if required
+func (p *GitLabProvider) RefreshSessionIfNeeded(s *sessions.SessionState) (bool, error) {
+	if s == nil || s.ExpiresOn.After(time.Now()) || s.RefreshToken == "" {
+		return false, nil
+	}
+
+	origExpiration := s.ExpiresOn
+
+	err := p.redeemRefreshToken(s)
+	if err != nil {
+		return false, fmt.Errorf("unable to redeem refresh token: %v", err)
+	}
+
+	fmt.Printf("refreshed id token %s (expired on %s)\n", s, origExpiration)
+	return true, nil
+}
+
+func (p *GitLabProvider) redeemRefreshToken(s *sessions.SessionState) (err error) {
+	c := oauth2.Config{
+		ClientID:     p.ClientID,
+		ClientSecret: p.ClientSecret,
+		Endpoint: oauth2.Endpoint{
+			TokenURL: p.RedeemURL.String(),
+		},
+	}
+	ctx := context.Background()
+	t := &oauth2.Token{
+		RefreshToken: s.RefreshToken,
+		Expiry:       time.Now().Add(-time.Hour),
+	}
+	token, err := c.TokenSource(ctx, t).Token()
+	if err != nil {
+		return fmt.Errorf("failed to get token: %v", err)
+	}
+	newSession, err := p.createSessionState(ctx, token)
+	if err != nil {
+		return fmt.Errorf("unable to update session: %v", err)
+	}
+	s.AccessToken = newSession.AccessToken
+	s.IDToken = newSession.IDToken
+	s.RefreshToken = newSession.RefreshToken
+	s.CreatedAt = newSession.CreatedAt
+	s.ExpiresOn = newSession.ExpiresOn
+	s.Email = newSession.Email
+	return
+}
+
+type gitlabUserInfo struct {
+	Username      string   `json:"nickname"`
+	Email         string   `json:"email"`
+	EmailVerified bool     `json:"email_verified"`
+	Groups        []string `json:"groups"`
+}
+
+func (p *GitLabProvider) getUserInfo(s *sessions.SessionState) (*gitlabUserInfo, error) {
+	// Retrieve user info JSON
+	// https://docs.gitlab.com/ee/integration/openid_connect_provider.html#shared-information
+
+	// Build user info url from login url of GitLab instance
+	userInfoURL := *p.LoginURL
+	userInfoURL.Path = "/oauth/userinfo"
+
+	req, err := http.NewRequest("GET", userInfoURL.String(), nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create user info request: %v", err)
+	}
+	req.Header.Set("Authorization", "Bearer "+s.AccessToken)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to perform user info request: %v", err)
+	}
+	var body []byte
+	body, err = ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	if err != nil {
+		return nil, fmt.Errorf("failed to read user info response: %v", err)
+	}
+
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("got %d during user info request: %s", resp.StatusCode, body)
+	}
+
+	var userInfo gitlabUserInfo
+	err = json.Unmarshal(body, &userInfo)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse user info: %v", err)
+	}
+
+	return &userInfo, nil
+}
+
+func (p *GitLabProvider) verifyGroupMembership(userInfo *gitlabUserInfo) error {
+	if p.Group == "" {
+		return nil
+	}
+
+	// Collect user group memberships
+	membershipSet := make(map[string]bool)
+	for _, group := range userInfo.Groups {
+		membershipSet[group] = true
+	}
+
+	// Find a valid group that they are a member of
+	validGroups := strings.Split(p.Group, " ")
+	for _, validGroup := range validGroups {
+		if _, ok := membershipSet[validGroup]; ok {
+			return nil
+		}
+	}
+
+	return fmt.Errorf("user is not a member of '%s'", p.Group)
+}
+
+func (p *GitLabProvider) verifyEmailDomain(userInfo *gitlabUserInfo) error {
+	if len(p.EmailDomains) == 0 || p.EmailDomains[0] == "*" {
+		return nil
+	}
+
+	for _, domain := range p.EmailDomains {
+		if strings.HasSuffix(userInfo.Email, domain) {
+			return nil
+		}
+	}
+
+	return fmt.Errorf("user email is not one of the valid domains '%v'", p.EmailDomains)
+}
+
+func (p *GitLabProvider) createSessionState(ctx context.Context, token *oauth2.Token) (*sessions.SessionState, error) {
+	rawIDToken, ok := token.Extra("id_token").(string)
+	if !ok {
+		return nil, fmt.Errorf("token response did not contain an id_token")
+	}
+
+	// Parse and verify ID Token payload.
+	idToken, err := p.Verifier.Verify(ctx, rawIDToken)
+	if err != nil {
+		return nil, fmt.Errorf("could not verify id_token: %v", err)
+	}
+
+	return &sessions.SessionState{
+		AccessToken:  token.AccessToken,
+		IDToken:      rawIDToken,
+		RefreshToken: token.RefreshToken,
+		CreatedAt:    time.Now(),
+		ExpiresOn:    idToken.Expiry,
+	}, nil
+}
+
+// ValidateSessionState checks that the session's IDToken is still valid
+func (p *GitLabProvider) ValidateSessionState(s *sessions.SessionState) bool {
+	ctx := context.Background()
+	_, err := p.Verifier.Verify(ctx, s.IDToken)
+	if err != nil {
+		return false
+	}
+
+	return true
+}
+
 // GetEmailAddress returns the Account email address
 func (p *GitLabProvider) GetEmailAddress(s *sessions.SessionState) (string, error) {
+	// Retrieve user info
+	userInfo, err := p.getUserInfo(s)
+	if err != nil {
+		return "", fmt.Errorf("failed to retrieve user info: %v", err)
+	}
 
-	req, err := http.NewRequest("GET",
-		p.ValidateURL.String()+"?access_token="+s.AccessToken, nil)
-	if err != nil {
-		logger.Printf("failed building request %s", err)
-		return "", err
+	// Check if email is verified
+	if !p.AllowUnverifiedEmail && !userInfo.EmailVerified {
+		return "", fmt.Errorf("user email is not verified")
 	}
-	json, err := requests.Request(req)
+
+	// Check if email has valid domain
+	err = p.verifyEmailDomain(userInfo)
 	if err != nil {
-		logger.Printf("failed making request %s", err)
-		return "", err
+		return "", fmt.Errorf("email domain check failed: %v", err)
 	}
-	return json.Get("email").String()
+
+	// Check group membership
+	err = p.verifyGroupMembership(userInfo)
+	if err != nil {
+		return "", fmt.Errorf("group membership check failed: %v", err)
+	}
+
+	return userInfo.Email, nil
+}
+
+// GetUserName returns the Account user name
+func (p *GitLabProvider) GetUserName(s *sessions.SessionState) (string, error) {
+	userInfo, err := p.getUserInfo(s)
+	if err != nil {
+		return "", fmt.Errorf("failed to retrieve user info: %v", err)
+	}
+
+	return userInfo.Username, nil
 }

providers/gitlab_test.go

@@ -25,104 +25,142 @@ func testGitLabProvider(hostname string) *GitLabProvider {
 		updateURL(p.Data().ProfileURL, hostname)
 		updateURL(p.Data().ValidateURL, hostname)
 	}
+
 	return p
 }
 
-func testGitLabBackend(payload string) *httptest.Server {
-	path := "/api/v4/user"
-	query := "access_token=imaginary_access_token"
+func testGitLabBackend() *httptest.Server {
+	userInfo := `
+		{
+			"nickname": "FooBar",
+			"email": "foo@bar.com",
+			"email_verified": false,
+			"groups": ["foo", "bar"]
+		}
+	`
+	authHeader := "Bearer gitlab_access_token"
 
 	return httptest.NewServer(http.HandlerFunc(
 		func(w http.ResponseWriter, r *http.Request) {
-			if r.URL.Path != path || r.URL.RawQuery != query {
-				w.WriteHeader(404)
+			if r.URL.Path == "/oauth/userinfo" {
+				if r.Header["Authorization"][0] == authHeader {
+					w.WriteHeader(200)
+					w.Write([]byte(userInfo))
+				} else {
+					w.WriteHeader(401)
+				}
 			} else {
-				w.WriteHeader(200)
-				w.Write([]byte(payload))
+				w.WriteHeader(404)
 			}
 		}))
 }
 
-func TestGitLabProviderDefaults(t *testing.T) {
-	p := testGitLabProvider("")
-	assert.NotEqual(t, nil, p)
-	assert.Equal(t, "GitLab", p.Data().ProviderName)
-	assert.Equal(t, "https://gitlab.com/oauth/authorize",
-		p.Data().LoginURL.String())
-	assert.Equal(t, "https://gitlab.com/oauth/token",
-		p.Data().RedeemURL.String())
-	assert.Equal(t, "https://gitlab.com/api/v4/user",
-		p.Data().ValidateURL.String())
-	assert.Equal(t, "read_user", p.Data().Scope)
-}
-
-func TestGitLabProviderOverrides(t *testing.T) {
-	p := NewGitLabProvider(
-		&ProviderData{
-			LoginURL: &url.URL{
-				Scheme: "https",
-				Host:   "example.com",
-				Path:   "/oauth/auth"},
-			RedeemURL: &url.URL{
-				Scheme: "https",
-				Host:   "example.com",
-				Path:   "/oauth/token"},
-			ValidateURL: &url.URL{
-				Scheme: "https",
-				Host:   "example.com",
-				Path:   "/api/v4/user"},
-			Scope: "profile"})
-	assert.NotEqual(t, nil, p)
-	assert.Equal(t, "GitLab", p.Data().ProviderName)
-	assert.Equal(t, "https://example.com/oauth/auth",
-		p.Data().LoginURL.String())
-	assert.Equal(t, "https://example.com/oauth/token",
-		p.Data().RedeemURL.String())
-	assert.Equal(t, "https://example.com/api/v4/user",
-		p.Data().ValidateURL.String())
-	assert.Equal(t, "profile", p.Data().Scope)
-}
-
-func TestGitLabProviderGetEmailAddress(t *testing.T) {
-	b := testGitLabBackend("{\"email\": \"michael.bland@gsa.gov\"}")
+func TestGitLabProviderBadToken(t *testing.T) {
+	b := testGitLabBackend()
 	defer b.Close()
 
 	bURL, _ := url.Parse(b.URL)
 	p := testGitLabProvider(bURL.Host)
 
-	session := &sessions.SessionState{AccessToken: "imaginary_access_token"}
+	session := &sessions.SessionState{AccessToken: "unexpected_gitlab_access_token"}
+	_, err := p.GetEmailAddress(session)
+	assert.NotEqual(t, nil, err)
+}
+
+func TestGitLabProviderUnverifiedEmailDenied(t *testing.T) {
+	b := testGitLabBackend()
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitLabProvider(bURL.Host)
+
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
+	_, err := p.GetEmailAddress(session)
+	assert.NotEqual(t, nil, err)
+}
+
+func TestGitLabProviderUnverifiedEmailAllowed(t *testing.T) {
+	b := testGitLabBackend()
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitLabProvider(bURL.Host)
+	p.AllowUnverifiedEmail = true
+
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
 	email, err := p.GetEmailAddress(session)
 	assert.Equal(t, nil, err)
-	assert.Equal(t, "michael.bland@gsa.gov", email)
+	assert.Equal(t, "foo@bar.com", email)
 }
 
-// Note that trying to trigger the "failed building request" case is not
-// practical, since the only way it can fail is if the URL fails to parse.
-func TestGitLabProviderGetEmailAddressFailedRequest(t *testing.T) {
-	b := testGitLabBackend("unused payload")
+func TestGitLabProviderUsername(t *testing.T) {
+	b := testGitLabBackend()
 	defer b.Close()
 
 	bURL, _ := url.Parse(b.URL)
 	p := testGitLabProvider(bURL.Host)
+	p.AllowUnverifiedEmail = true
 
-	// We'll trigger a request failure by using an unexpected access
-	// token. Alternatively, we could allow the parsing of the payload as
-	// JSON to fail.
-	session := &sessions.SessionState{AccessToken: "unexpected_access_token"}
-	email, err := p.GetEmailAddress(session)
-	assert.NotEqual(t, nil, err)
-	assert.Equal(t, "", email)
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
+	username, err := p.GetUserName(session)
+	assert.Equal(t, nil, err)
+	assert.Equal(t, "FooBar", username)
 }
 
-func TestGitLabProviderGetEmailAddressEmailNotPresentInPayload(t *testing.T) {
-	b := testGitLabBackend("{\"foo\": \"bar\"}")
+func TestGitLabProviderGroupMembershipValid(t *testing.T) {
+	b := testGitLabBackend()
 	defer b.Close()
 
 	bURL, _ := url.Parse(b.URL)
 	p := testGitLabProvider(bURL.Host)
+	p.AllowUnverifiedEmail = true
+	p.Group = "foo"
 
-	session := &sessions.SessionState{AccessToken: "imaginary_access_token"}
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
 	email, err := p.GetEmailAddress(session)
-	assert.NotEqual(t, nil, err)
-	assert.Equal(t, "", email)
+	assert.Equal(t, nil, err)
+	assert.Equal(t, "foo@bar.com", email)
+}
+
+func TestGitLabProviderGroupMembershipMissing(t *testing.T) {
+	b := testGitLabBackend()
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitLabProvider(bURL.Host)
+	p.AllowUnverifiedEmail = true
+	p.Group = "baz"
+
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
+	_, err := p.GetEmailAddress(session)
+	assert.NotEqual(t, nil, err)
+}
+
+func TestGitLabProviderEmailDomainValid(t *testing.T) {
+	b := testGitLabBackend()
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitLabProvider(bURL.Host)
+	p.AllowUnverifiedEmail = true
+	p.EmailDomains = []string{"bar.com"}
+
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
+	email, err := p.GetEmailAddress(session)
+	assert.Equal(t, nil, err)
+	assert.Equal(t, "foo@bar.com", email)
+}
+
+func TestGitLabProviderEmailDomainInvalid(t *testing.T) {
+	b := testGitLabBackend()
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitLabProvider(bURL.Host)
+	p.AllowUnverifiedEmail = true
+	p.EmailDomains = []string{"baz.com"}
+
+	session := &sessions.SessionState{AccessToken: "gitlab_access_token"}
+	_, err := p.GetEmailAddress(session)
+	assert.NotEqual(t, nil, err)
 }