allow to set the JWT claim key that contains permissions (#3560)

README.md

@@ -1147,7 +1147,7 @@ If the URL returns a status code that begins with `20` (i.e. `200`), authenticat
 ```json
 {
   "user": "",
-  "password": "",
+  "password": ""
 }
 ```
 
@@ -1171,9 +1171,10 @@ Authentication can be delegated to an external identity server, that is capable
 ```yml
 authMethod: jwt
 authJWTJWKS: http://my_identity_server/jwks_endpoint
+authJWTClaimKey: mediamtx_permissions
 ```
 
-The JWT is expected to contain the `mediamtx_permissions` scope, with a list of permissions in the same format as the one of user permissions:
+The JWT is expected to contain a claim, with a list of permissions in the same format as the one of user permissions:
 
 ```json
 {

apidocs/openapi.yaml

@@ -87,6 +87,8 @@ components:
             $ref: '#/components/schemas/AuthInternalUserPermission'
         authJWTJWKS:
           type: string
+        authJWTClaimKey:
+          type: string
 
         # Control API
         api:

internal/auth/manager.go

@@ -99,7 +99,33 @@ func matchesPermission(perms []conf.AuthInternalUserPermission, req *Request) bo
 
 type customClaims struct {
 	jwt.RegisteredClaims
-	MediaMTXPermissions []conf.AuthInternalUserPermission `json:"mediamtx_permissions"`
+	permissionsKey string
+	permissions    []conf.AuthInternalUserPermission
+}
+
+func (c *customClaims) UnmarshalJSON(b []byte) error {
+	err := json.Unmarshal(b, &c.RegisteredClaims)
+	if err != nil {
+		return err
+	}
+
+	var claimMap map[string]json.RawMessage
+	err = json.Unmarshal(b, &claimMap)
+	if err != nil {
+		return err
+	}
+
+	rawPermissions, ok := claimMap[c.permissionsKey]
+	if !ok {
+		return fmt.Errorf("claim '%s' not found inside JWT", c.permissionsKey)
+	}
+
+	err = json.Unmarshal(rawPermissions, &c.permissions)
+	if err != nil {
+		return err
+	}
+
+	return nil
 }
 
 // Manager is the authentication manager.
@@ -109,6 +135,7 @@ type Manager struct {
 	HTTPAddress     string
 	HTTPExclude     []conf.AuthInternalUserPermission
 	JWTJWKS         string
+	JWTClaimKey     string
 	ReadTimeout     time.Duration
 	RTSPAuthMethods []auth.ValidateMethod
 
@@ -270,12 +297,13 @@ func (m *Manager) authenticateJWT(req *Request) error {
 	}
 
 	var cc customClaims
+	cc.permissionsKey = m.JWTClaimKey
 	_, err = jwt.ParseWithClaims(v["jwt"][0], &cc, keyfunc)
 	if err != nil {
 		return err
 	}
 
-	if !matchesPermission(cc.MediaMTXPermissions, req) {
+	if !matchesPermission(cc.permissions, req) {
 		return fmt.Errorf("user doesn't have permission to perform action")
 	}
 

internal/auth/manager_test.go

@@ -327,7 +327,7 @@ func TestAuthJWT(t *testing.T) {
 
 	type customClaims struct {
 		jwt.RegisteredClaims
-		MediaMTXPermissions []conf.AuthInternalUserPermission `json:"mediamtx_permissions"`
+		MediaMTXPermissions []conf.AuthInternalUserPermission `json:"my_permission_key"`
 	}
 
 	claims := customClaims{
@@ -351,8 +351,9 @@ func TestAuthJWT(t *testing.T) {
 	require.NoError(t, err)
 
 	m := Manager{
-		Method:  conf.AuthMethodJWT,
-		JWTJWKS: "http://localhost:4567/jwks",
+		Method:      conf.AuthMethodJWT,
+		JWTJWKS:     "http://localhost:4567/jwks",
+		JWTClaimKey: "my_permission_key",
 	}
 
 	err = m.Authenticate(&Request{

internal/conf/conf.go

@@ -177,6 +177,7 @@ type Conf struct {
 	ExternalAuthenticationURL *string                     `json:"externalAuthenticationURL,omitempty"` // deprecated
 	AuthHTTPExclude           AuthInternalUserPermissions `json:"authHTTPExclude"`
 	AuthJWTJWKS               string                      `json:"authJWTJWKS"`
+	AuthJWTClaimKey           string                      `json:"authJWTClaimKey"`
 
 	// Control API
 	API               bool       `json:"api"`
@@ -323,6 +324,7 @@ func (conf *Conf) setDefaults() {
 			Action: AuthActionPprof,
 		},
 	}
+	conf.AuthJWTClaimKey = "mediamtx_permissions"
 
 	// Control API
 	conf.APIAddress = ":9997"
@@ -562,6 +564,9 @@ func (conf *Conf) Validate() error {
 		if conf.AuthJWTJWKS == "" {
 			return fmt.Errorf("'authJWTJWKS' is empty")
 		}
+		if conf.AuthJWTClaimKey == "" {
+			return fmt.Errorf("'authJWTClaimKey' is empty")
+		}
 	}
 
 	// RTSP

internal/conf/conf_test.go

@@ -357,6 +357,13 @@ func TestConfErrors(t *testing.T) {
 			`record path './recordings/%path/%Y-%m-%d_%H-%M-%S' is missing one of the` +
 				` mandatory elements for the playback server to work: %Y %m %d %H %M %S %f`,
 		},
+		{
+			"jwt claim key empty",
+			"authMethod: jwt\n" +
+				"authJWTJWKS: https://not-real.com\n" +
+				"authJWTClaimKey: \"\"",
+			"'authJWTClaimKey' is empty",
+		},
 	} {
 		t.Run(ca.name, func(t *testing.T) {
 			tmpf, err := createTempFile([]byte(ca.conf))

internal/core/core.go

@@ -287,6 +287,7 @@ func (p *Core) createResources(initial bool) error {
 			HTTPAddress:     p.conf.AuthHTTPAddress,
 			HTTPExclude:     p.conf.AuthHTTPExclude,
 			JWTJWKS:         p.conf.AuthJWTJWKS,
+			JWTClaimKey:     p.conf.AuthJWTClaimKey,
 			ReadTimeout:     time.Duration(p.conf.ReadTimeout),
 			RTSPAuthMethods: p.conf.RTSPAuthMethods,
 		}
@@ -674,6 +675,7 @@ func (p *Core) closeResources(newConf *conf.Conf, calledByAPI bool) {
 		newConf.AuthHTTPAddress != p.conf.AuthHTTPAddress ||
 		!reflect.DeepEqual(newConf.AuthHTTPExclude, p.conf.AuthHTTPExclude) ||
 		newConf.AuthJWTJWKS != p.conf.AuthJWTJWKS ||
+		newConf.AuthJWTClaimKey != p.conf.AuthJWTClaimKey ||
 		newConf.ReadTimeout != p.conf.ReadTimeout ||
 		!reflect.DeepEqual(newConf.RTSPAuthMethods, p.conf.RTSPAuthMethods)
 	if !closeAuthManager && !reflect.DeepEqual(newConf.AuthInternalUsers, p.conf.AuthInternalUsers) {

mediamtx.yml

@@ -121,6 +121,8 @@ authHTTPExclude:
 # This is the JWKS URL that will be used to pull (once) the public key that allows
 # to validate JWTs.
 authJWTJWKS:
+# name of the claim that contains permissions.
+authJWTClaimKey: mediamtx_permissions
 
 ###############################################
 # Global settings -> Control API