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mirror of https://github.com/labstack/echo.git synced 2024-11-30 08:46:41 +02:00
echo/middleware/jwt.go
Philipp Thun 499097e061 Ignore case of auth scheme in request header
Some clients send an authorization header containing the "bearer"
keyword in lower case. This led to echo responding with "missing or
malformed jwt".

Request.BasicAuth (net/http) ignores the basic auth scheme's case since
a while: https://go-review.googlesource.com/c/go/+/111516/
2021-08-10 20:32:01 +03:00

348 lines
10 KiB
Go

// +build go1.15
package middleware
import (
"errors"
"fmt"
"net/http"
"reflect"
"strings"
"github.com/golang-jwt/jwt"
"github.com/labstack/echo/v4"
)
type (
// JWTConfig defines the config for JWT middleware.
JWTConfig struct {
// Skipper defines a function to skip middleware.
Skipper Skipper
// BeforeFunc defines a function which is executed just before the middleware.
BeforeFunc BeforeFunc
// SuccessHandler defines a function which is executed for a valid token.
SuccessHandler JWTSuccessHandler
// ErrorHandler defines a function which is executed for an invalid token.
// It may be used to define a custom JWT error.
ErrorHandler JWTErrorHandler
// ErrorHandlerWithContext is almost identical to ErrorHandler, but it's passed the current context.
ErrorHandlerWithContext JWTErrorHandlerWithContext
// Signing key to validate token.
// This is one of the three options to provide a token validation key.
// The order of precedence is a user-defined KeyFunc, SigningKeys and SigningKey.
// Required if neither user-defined KeyFunc nor SigningKeys is provided.
SigningKey interface{}
// Map of signing keys to validate token with kid field usage.
// This is one of the three options to provide a token validation key.
// The order of precedence is a user-defined KeyFunc, SigningKeys and SigningKey.
// Required if neither user-defined KeyFunc nor SigningKey is provided.
SigningKeys map[string]interface{}
// Signing method used to check the token's signing algorithm.
// Optional. Default value HS256.
SigningMethod string
// Context key to store user information from the token into context.
// Optional. Default value "user".
ContextKey string
// Claims are extendable claims data defining token content. Used by default ParseTokenFunc implementation.
// Not used if custom ParseTokenFunc is set.
// Optional. Default value jwt.MapClaims
Claims jwt.Claims
// TokenLookup is a string in the form of "<source>:<name>" or "<source>:<name>,<source>:<name>" that is used
// to extract token from the request.
// Optional. Default value "header:Authorization".
// Possible values:
// - "header:<name>"
// - "query:<name>"
// - "param:<name>"
// - "cookie:<name>"
// - "form:<name>"
// Multiply sources example:
// - "header: Authorization,cookie: myowncookie"
TokenLookup string
// AuthScheme to be used in the Authorization header.
// Optional. Default value "Bearer".
AuthScheme string
// KeyFunc defines a user-defined function that supplies the public key for a token validation.
// The function shall take care of verifying the signing algorithm and selecting the proper key.
// A user-defined KeyFunc can be useful if tokens are issued by an external party.
// Used by default ParseTokenFunc implementation.
//
// When a user-defined KeyFunc is provided, SigningKey, SigningKeys, and SigningMethod are ignored.
// This is one of the three options to provide a token validation key.
// The order of precedence is a user-defined KeyFunc, SigningKeys and SigningKey.
// Required if neither SigningKeys nor SigningKey is provided.
// Not used if custom ParseTokenFunc is set.
// Default to an internal implementation verifying the signing algorithm and selecting the proper key.
KeyFunc jwt.Keyfunc
// ParseTokenFunc defines a user-defined function that parses token from given auth. Returns an error when token
// parsing fails or parsed token is invalid.
// Defaults to implementation using `github.com/golang-jwt/jwt` as JWT implementation library
ParseTokenFunc func(auth string, c echo.Context) (interface{}, error)
}
// JWTSuccessHandler defines a function which is executed for a valid token.
JWTSuccessHandler func(echo.Context)
// JWTErrorHandler defines a function which is executed for an invalid token.
JWTErrorHandler func(error) error
// JWTErrorHandlerWithContext is almost identical to JWTErrorHandler, but it's passed the current context.
JWTErrorHandlerWithContext func(error, echo.Context) error
jwtExtractor func(echo.Context) (string, error)
)
// Algorithms
const (
AlgorithmHS256 = "HS256"
)
// Errors
var (
ErrJWTMissing = echo.NewHTTPError(http.StatusBadRequest, "missing or malformed jwt")
ErrJWTInvalid = echo.NewHTTPError(http.StatusUnauthorized, "invalid or expired jwt")
)
var (
// DefaultJWTConfig is the default JWT auth middleware config.
DefaultJWTConfig = JWTConfig{
Skipper: DefaultSkipper,
SigningMethod: AlgorithmHS256,
ContextKey: "user",
TokenLookup: "header:" + echo.HeaderAuthorization,
AuthScheme: "Bearer",
Claims: jwt.MapClaims{},
KeyFunc: nil,
}
)
// JWT returns a JSON Web Token (JWT) auth middleware.
//
// For valid token, it sets the user in context and calls next handler.
// For invalid token, it returns "401 - Unauthorized" error.
// For missing token, it returns "400 - Bad Request" error.
//
// See: https://jwt.io/introduction
// See `JWTConfig.TokenLookup`
func JWT(key interface{}) echo.MiddlewareFunc {
c := DefaultJWTConfig
c.SigningKey = key
return JWTWithConfig(c)
}
// JWTWithConfig returns a JWT auth middleware with config.
// See: `JWT()`.
func JWTWithConfig(config JWTConfig) echo.MiddlewareFunc {
// Defaults
if config.Skipper == nil {
config.Skipper = DefaultJWTConfig.Skipper
}
if config.SigningKey == nil && len(config.SigningKeys) == 0 && config.KeyFunc == nil && config.ParseTokenFunc == nil {
panic("echo: jwt middleware requires signing key")
}
if config.SigningMethod == "" {
config.SigningMethod = DefaultJWTConfig.SigningMethod
}
if config.ContextKey == "" {
config.ContextKey = DefaultJWTConfig.ContextKey
}
if config.Claims == nil {
config.Claims = DefaultJWTConfig.Claims
}
if config.TokenLookup == "" {
config.TokenLookup = DefaultJWTConfig.TokenLookup
}
if config.AuthScheme == "" {
config.AuthScheme = DefaultJWTConfig.AuthScheme
}
if config.KeyFunc == nil {
config.KeyFunc = config.defaultKeyFunc
}
if config.ParseTokenFunc == nil {
config.ParseTokenFunc = config.defaultParseToken
}
// Initialize
// Split sources
sources := strings.Split(config.TokenLookup, ",")
var extractors []jwtExtractor
for _, source := range sources {
parts := strings.Split(source, ":")
switch parts[0] {
case "query":
extractors = append(extractors, jwtFromQuery(parts[1]))
case "param":
extractors = append(extractors, jwtFromParam(parts[1]))
case "cookie":
extractors = append(extractors, jwtFromCookie(parts[1]))
case "form":
extractors = append(extractors, jwtFromForm(parts[1]))
case "header":
extractors = append(extractors, jwtFromHeader(parts[1], config.AuthScheme))
}
}
return func(next echo.HandlerFunc) echo.HandlerFunc {
return func(c echo.Context) error {
if config.Skipper(c) {
return next(c)
}
if config.BeforeFunc != nil {
config.BeforeFunc(c)
}
var auth string
var err error
for _, extractor := range extractors {
// Extract token from extractor, if it's not fail break the loop and
// set auth
auth, err = extractor(c)
if err == nil {
break
}
}
// If none of extractor has a token, handle error
if err != nil {
if config.ErrorHandler != nil {
return config.ErrorHandler(err)
}
if config.ErrorHandlerWithContext != nil {
return config.ErrorHandlerWithContext(err, c)
}
return err
}
token, err := config.ParseTokenFunc(auth, c)
if err == nil {
// Store user information from token into context.
c.Set(config.ContextKey, token)
if config.SuccessHandler != nil {
config.SuccessHandler(c)
}
return next(c)
}
if config.ErrorHandler != nil {
return config.ErrorHandler(err)
}
if config.ErrorHandlerWithContext != nil {
return config.ErrorHandlerWithContext(err, c)
}
return &echo.HTTPError{
Code: ErrJWTInvalid.Code,
Message: ErrJWTInvalid.Message,
Internal: err,
}
}
}
}
func (config *JWTConfig) defaultParseToken(auth string, c echo.Context) (interface{}, error) {
token := new(jwt.Token)
var err error
// Issue #647, #656
if _, ok := config.Claims.(jwt.MapClaims); ok {
token, err = jwt.Parse(auth, config.KeyFunc)
} else {
t := reflect.ValueOf(config.Claims).Type().Elem()
claims := reflect.New(t).Interface().(jwt.Claims)
token, err = jwt.ParseWithClaims(auth, claims, config.KeyFunc)
}
if err != nil {
return nil, err
}
if !token.Valid {
return nil, errors.New("invalid token")
}
return token, nil
}
// defaultKeyFunc returns a signing key of the given token.
func (config *JWTConfig) defaultKeyFunc(t *jwt.Token) (interface{}, error) {
// Check the signing method
if t.Method.Alg() != config.SigningMethod {
return nil, fmt.Errorf("unexpected jwt signing method=%v", t.Header["alg"])
}
if len(config.SigningKeys) > 0 {
if kid, ok := t.Header["kid"].(string); ok {
if key, ok := config.SigningKeys[kid]; ok {
return key, nil
}
}
return nil, fmt.Errorf("unexpected jwt key id=%v", t.Header["kid"])
}
return config.SigningKey, nil
}
// jwtFromHeader returns a `jwtExtractor` that extracts token from the request header.
func jwtFromHeader(header string, authScheme string) jwtExtractor {
return func(c echo.Context) (string, error) {
auth := c.Request().Header.Get(header)
l := len(authScheme)
if len(auth) > l+1 && strings.EqualFold(auth[:l], authScheme) {
return auth[l+1:], nil
}
return "", ErrJWTMissing
}
}
// jwtFromQuery returns a `jwtExtractor` that extracts token from the query string.
func jwtFromQuery(param string) jwtExtractor {
return func(c echo.Context) (string, error) {
token := c.QueryParam(param)
if token == "" {
return "", ErrJWTMissing
}
return token, nil
}
}
// jwtFromParam returns a `jwtExtractor` that extracts token from the url param string.
func jwtFromParam(param string) jwtExtractor {
return func(c echo.Context) (string, error) {
token := c.Param(param)
if token == "" {
return "", ErrJWTMissing
}
return token, nil
}
}
// jwtFromCookie returns a `jwtExtractor` that extracts token from the named cookie.
func jwtFromCookie(name string) jwtExtractor {
return func(c echo.Context) (string, error) {
cookie, err := c.Cookie(name)
if err != nil {
return "", ErrJWTMissing
}
return cookie.Value, nil
}
}
// jwtFromForm returns a `jwtExtractor` that extracts token from the form field.
func jwtFromForm(name string) jwtExtractor {
return func(c echo.Context) (string, error) {
field := c.FormValue(name)
if field == "" {
return "", ErrJWTMissing
}
return field, nil
}
}