add ServerConn.VerifyCredentials() (#555)

README.md

@@ -30,6 +30,7 @@ Features:
     * Pause without disconnecting from the server
 * Server
   * Handle requests from clients
+  * Validate client credentials
   * Read media streams from clients ("record")
     * Read streams with the UDP or TCP transport protocol
     * Read TLS-encrypted streams (TCP only)
@@ -94,6 +95,7 @@ Features:
 * [client-record-format-vp9](examples/client-record-format-vp9/main.go)
 * [server](examples/server/main.go)
 * [server-tls](examples/server-tls/main.go)
+* [server-auth](examples/server-auth/main.go)
 * [server-h264-save-to-disk](examples/server-h264-save-to-disk/main.go)
 * [proxy](examples/proxy/main.go)
 

client.go

@@ -34,6 +34,10 @@ import (
 	"github.com/bluenviron/gortsplib/v4/pkg/sdp"
 )
 
+const (
+	clientUserAgent = "gortsplib"
+)
+
 // avoid an int64 overflow and preserve resolution by splitting division into two parts:
 // first add the integer part, then the decimal part.
 func multiplyAndDivide(v, m, d time.Duration) time.Duration {
@@ -386,7 +390,7 @@ func (c *Client) Start(scheme string, host string) error {
 		return fmt.Errorf("MaxPacketSize must be less than %d", udpMaxPayloadSize)
 	}
 	if c.UserAgent == "" {
-		c.UserAgent = "gortsplib"
+		c.UserAgent = clientUserAgent
 	}
 
 	// system functions

examples/server-auth/main.go

@@ -0,0 +1,195 @@
+package main
+
+import (
+	"log"
+	"sync"
+
+	"github.com/pion/rtp"
+
+	"github.com/bluenviron/gortsplib/v4"
+	"github.com/bluenviron/gortsplib/v4/pkg/base"
+	"github.com/bluenviron/gortsplib/v4/pkg/description"
+	"github.com/bluenviron/gortsplib/v4/pkg/format"
+	"github.com/bluenviron/gortsplib/v4/pkg/liberrors"
+)
+
+// This example shows how to
+// 1. create a RTSP server which accepts plain connections
+// 2. allow a single client to publish a stream with TCP or UDP, if it provides credentials
+// 3. allow multiple clients to read that stream with TCP, UDP or UDP-multicast, if they provide credentials
+
+const (
+	// credentials required to publish the stream
+	publishUser = "publishuser"
+	publishPass = "publishpass"
+
+	// credentials required to read the stream
+	readUser = "readuser"
+	readPass = "readpass"
+)
+
+type serverHandler struct {
+	s         *gortsplib.Server
+	mutex     sync.Mutex
+	stream    *gortsplib.ServerStream
+	publisher *gortsplib.ServerSession
+}
+
+// called when a connection is opened.
+func (sh *serverHandler) OnConnOpen(ctx *gortsplib.ServerHandlerOnConnOpenCtx) {
+	log.Printf("conn opened")
+}
+
+// called when a connection is closed.
+func (sh *serverHandler) OnConnClose(ctx *gortsplib.ServerHandlerOnConnCloseCtx) {
+	log.Printf("conn closed (%v)", ctx.Error)
+}
+
+// called when a session is opened.
+func (sh *serverHandler) OnSessionOpen(ctx *gortsplib.ServerHandlerOnSessionOpenCtx) {
+	log.Printf("session opened")
+}
+
+// called when a session is closed.
+func (sh *serverHandler) OnSessionClose(ctx *gortsplib.ServerHandlerOnSessionCloseCtx) {
+	log.Printf("session closed")
+
+	sh.mutex.Lock()
+	defer sh.mutex.Unlock()
+
+	// if the session is the publisher,
+	// close the stream and disconnect any reader.
+	if sh.stream != nil && ctx.Session == sh.publisher {
+		sh.stream.Close()
+		sh.stream = nil
+	}
+}
+
+// called when receiving a DESCRIBE request.
+func (sh *serverHandler) OnDescribe(ctx *gortsplib.ServerHandlerOnDescribeCtx) (*base.Response, *gortsplib.ServerStream, error) {
+	log.Printf("describe request")
+
+	// Verify reader credentials.
+	// In case of readers, credentials have to be verified during DESCRIBE and SETUP.
+	ok := ctx.Conn.VerifyCredentials(ctx.Request, readUser, readPass)
+	if !ok {
+		return &base.Response{
+			StatusCode: base.StatusUnauthorized,
+		}, nil, liberrors.ErrServerAuth{}
+	}
+
+	sh.mutex.Lock()
+	defer sh.mutex.Unlock()
+
+	// no one is publishing yet
+	if sh.stream == nil {
+		return &base.Response{
+			StatusCode: base.StatusNotFound,
+		}, nil, nil
+	}
+
+	// send medias that are being published to the client
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, sh.stream, nil
+}
+
+// called when receiving an ANNOUNCE request.
+func (sh *serverHandler) OnAnnounce(ctx *gortsplib.ServerHandlerOnAnnounceCtx) (*base.Response, error) {
+	log.Printf("announce request")
+
+	// Verify publisher credentials.
+	// In case of publishers, credentials have to be verified during ANNOUNCE.
+	ok := ctx.Conn.VerifyCredentials(ctx.Request, publishUser, publishPass)
+	if !ok {
+		return &base.Response{
+			StatusCode: base.StatusUnauthorized,
+		}, liberrors.ErrServerAuth{}
+	}
+
+	sh.mutex.Lock()
+	defer sh.mutex.Unlock()
+
+	// disconnect existing publisher
+	if sh.stream != nil {
+		sh.stream.Close()
+		sh.publisher.Close()
+	}
+
+	// create the stream and save the publisher
+	sh.stream = gortsplib.NewServerStream(sh.s, ctx.Description)
+	sh.publisher = ctx.Session
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, nil
+}
+
+// called when receiving a SETUP request.
+func (sh *serverHandler) OnSetup(ctx *gortsplib.ServerHandlerOnSetupCtx) (*base.Response, *gortsplib.ServerStream, error) {
+	log.Printf("setup request")
+
+	// Verify reader credentials.
+	// In case of readers, credentials have to be verified during DESCRIBE and SETUP.
+	if ctx.Session.State() == gortsplib.ServerSessionStateInitial {
+		ok := ctx.Conn.VerifyCredentials(ctx.Request, readUser, readPass)
+		if !ok {
+			return &base.Response{
+				StatusCode: base.StatusUnauthorized,
+			}, nil, liberrors.ErrServerAuth{}
+		}
+	}
+
+	// no one is publishing yet
+	if sh.stream == nil {
+		return &base.Response{
+			StatusCode: base.StatusNotFound,
+		}, nil, nil
+	}
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, sh.stream, nil
+}
+
+// called when receiving a PLAY request.
+func (sh *serverHandler) OnPlay(ctx *gortsplib.ServerHandlerOnPlayCtx) (*base.Response, error) {
+	log.Printf("play request")
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, nil
+}
+
+// called when receiving a RECORD request.
+func (sh *serverHandler) OnRecord(ctx *gortsplib.ServerHandlerOnRecordCtx) (*base.Response, error) {
+	log.Printf("record request")
+
+	// called when receiving a RTP packet
+	ctx.Session.OnPacketRTPAny(func(medi *description.Media, forma format.Format, pkt *rtp.Packet) {
+		// route the RTP packet to all readers
+		sh.stream.WritePacketRTP(medi, pkt)
+	})
+
+	return &base.Response{
+		StatusCode: base.StatusOK,
+	}, nil
+}
+
+func main() {
+	// configure the server
+	h := &serverHandler{}
+	h.s = &gortsplib.Server{
+		Handler:           h,
+		RTSPAddress:       ":8554",
+		UDPRTPAddress:     ":8000",
+		UDPRTCPAddress:    ":8001",
+		MulticastIPRange:  "224.1.0.0/16",
+		MulticastRTPPort:  8002,
+		MulticastRTCPPort: 8003,
+	}
+
+	// start server and wait until a fatal error
+	log.Printf("server is ready")
+	panic(h.s.StartAndWait())
+}

pkg/auth/sender.go

@@ -53,11 +53,11 @@ func (se *Sender) AddAuthorization(req *base.Request) {
 		Method: se.authHeader.Method,
 	}
 
+	h.Username = se.user
+
 	if se.authHeader.Method == headers.AuthMethodBasic {
-		h.BasicUser = se.user
 		h.BasicPass = se.pass
 	} else { // digest
-		h.Username = se.user
 		h.Realm = se.authHeader.Realm
 		h.Nonce = se.authHeader.Nonce
 		h.URI = urStr

pkg/auth/verify.go

@@ -61,7 +61,7 @@ const (
 	VerifyMethodDigestSHA256
 )
 
-// Verify validates a request sent by a client.
+// Verify verifies a request sent by a client.
 func Verify(
 	req *base.Request,
 	user string,
@@ -119,7 +119,7 @@ func Verify(
 		}
 
 	case auth.Method == headers.AuthMethodBasic && contains(methods, VerifyMethodBasic):
-		if auth.BasicUser != user {
+		if auth.Username != user {
 			return fmt.Errorf("authentication failed")
 		}
 

pkg/headers/authorization.go

@@ -13,11 +13,16 @@ type Authorization struct {
 	// authentication method
 	Method AuthMethod
 
+	// username
+	Username string
+
 	//
 	// Basic authentication fields
 	//
 
 	// user
+	//
+	// Deprecated: replaced by Username.
 	BasicUser string
 
 	// password
@@ -27,9 +32,6 @@ type Authorization struct {
 	// Digest authentication fields
 	//
 
-	// username
-	Username string
-
 	// realm
 	Realm string
 
@@ -89,7 +91,8 @@ func (h *Authorization) Unmarshal(v base.HeaderValue) error {
 			return fmt.Errorf("invalid value")
 		}
 
-		h.BasicUser, h.BasicPass = tmp2[0], tmp2[1]
+		h.Username, h.BasicPass = tmp2[0], tmp2[1]
+		h.BasicUser = h.Username
 	} else { // digest
 		kvs, err := keyValParse(v0, ',')
 		if err != nil {
@@ -149,8 +152,11 @@ func (h *Authorization) Unmarshal(v base.HeaderValue) error {
 // Marshal encodes an Authorization header.
 func (h Authorization) Marshal() base.HeaderValue {
 	if h.Method == AuthMethodBasic {
+		if h.BasicUser != "" {
+			h.Username = h.BasicUser
+		}
 		return base.HeaderValue{"Basic " +
-			base64.StdEncoding.EncodeToString([]byte(h.BasicUser+":"+h.BasicPass))}
+			base64.StdEncoding.EncodeToString([]byte(h.Username+":"+h.BasicPass))}
 	}
 
 	ret := "Digest " +

pkg/headers/authorization_test.go

@@ -24,6 +24,7 @@ var casesAuthorization = []struct {
 		base.HeaderValue{"Basic bXl1c2VyOm15cGFzcw=="},
 		Authorization{
 			Method:    AuthMethodBasic,
+			Username:  "myuser",
 			BasicUser: "myuser",
 			BasicPass: "mypass",
 		},

pkg/liberrors/server.go

@@ -270,3 +270,13 @@ func (ErrServerInvalidSetupPath) Error() string {
 		"This typically happens when VLC fails a request, and then switches to an " +
 		"unsupported RTSP dialect"
 }
+
+// ErrServerAuth is an error that can be returned by a server.
+// If a client did not provide credentials, it will be asked for
+// credentials instead of being kicked out.
+type ErrServerAuth struct{}
+
+// Error implements the error interface.
+func (e ErrServerAuth) Error() string {
+	return "authentication error"
+}

server.go

@@ -9,10 +9,16 @@ import (
 	"sync"
 	"time"
 
+	"github.com/bluenviron/gortsplib/v4/pkg/auth"
 	"github.com/bluenviron/gortsplib/v4/pkg/base"
 	"github.com/bluenviron/gortsplib/v4/pkg/liberrors"
 )
 
+const (
+	serverHeader    = "gortsplib"
+	serverAuthRealm = "ipcam"
+)
+
 func extractPort(address string) (int, error) {
 	_, tmp, err := net.SplitHostPort(address)
 	if err != nil {
@@ -88,6 +94,9 @@ type Server struct {
 	MaxPacketSize int
 	// disable automatic RTCP sender reports.
 	DisableRTCPSenderReports bool
+	// authentication methods.
+	// It defaults to plain and digest+MD5.
+	AuthMethods []auth.VerifyMethod
 
 	//
 	// handler (optional)
@@ -156,6 +165,11 @@ func (s *Server) Start() error {
 	} else if s.MaxPacketSize > udpMaxPayloadSize {
 		return fmt.Errorf("MaxPacketSize must be less than %d", udpMaxPayloadSize)
 	}
+	if len(s.AuthMethods) == 0 {
+		// disable VerifyMethodDigestSHA256 unless explicitly set
+		// since it prevents FFmpeg from authenticating
+		s.AuthMethods = []auth.VerifyMethod{auth.VerifyMethodBasic, auth.VerifyMethodDigestMD5}
+	}
 
 	// system functions
 	if s.Listen == nil {

server_conn.go

@@ -10,10 +10,12 @@ import (
 	"strings"
 	"time"
 
+	"github.com/bluenviron/gortsplib/v4/pkg/auth"
 	"github.com/bluenviron/gortsplib/v4/pkg/base"
 	"github.com/bluenviron/gortsplib/v4/pkg/bytecounter"
 	"github.com/bluenviron/gortsplib/v4/pkg/conn"
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
+	"github.com/bluenviron/gortsplib/v4/pkg/headers"
 	"github.com/bluenviron/gortsplib/v4/pkg/liberrors"
 )
 
@@ -46,6 +48,12 @@ func serverSideDescription(d *description.Session) *description.Session {
 	return out
 }
 
+func credentialsProvided(req *base.Request) bool {
+	var auth headers.Authorization
+	err := auth.Unmarshal(req.Header["Authorization"])
+	return err == nil && auth.Username != ""
+}
+
 type readReq struct {
 	req *base.Request
 	res chan error
@@ -64,6 +72,7 @@ type ServerConn struct {
 	conn       *conn.Conn
 	session    *ServerSession
 	reader     *serverConnReader
+	authNonce  string
 
 	// in
 	chRemoveSession chan *ServerSession
@@ -137,6 +146,48 @@ func (sc *ServerConn) Stats() *StatsConn {
 	}
 }
 
+// VerifyCredentials verifies credentials provided by the user.
+func (sc *ServerConn) VerifyCredentials(
+	req *base.Request,
+	expectedUser string,
+	expectedPass string,
+) bool {
+	// we do not support using an empty string as user
+	// since it interferes with credentialsProvided()
+	if expectedUser == "" {
+		return false
+	}
+
+	if sc.authNonce == "" {
+		n, err := auth.GenerateNonce()
+		if err != nil {
+			return false
+		}
+		sc.authNonce = n
+	}
+
+	err := auth.Verify(
+		req,
+		expectedUser,
+		expectedPass,
+		sc.s.AuthMethods,
+		serverAuthRealm,
+		sc.authNonce)
+
+	return (err == nil)
+}
+
+func (sc *ServerConn) handleAuthError(req *base.Request, res *base.Response) error {
+	// if credentials have not been provided, clear error and send the WWW-Authenticate header.
+	if !credentialsProvided(req) {
+		res.Header["WWW-Authenticate"] = auth.GenerateWWWAuthenticate(sc.s.AuthMethods, serverAuthRealm, sc.authNonce)
+		return nil
+	}
+
+	// if credentials have been provided (and are wrong), close the connection.
+	return liberrors.ErrServerAuth{}
+}
+
 func (sc *ServerConn) ip() net.IP {
 	return sc.remoteAddr.IP
 }
@@ -386,14 +437,20 @@ func (sc *ServerConn) handleRequestOuter(req *base.Request) error {
 		res.Header = make(base.Header)
 	}
 
+	// handle auth errors
+	var eerr1 liberrors.ErrServerAuth
+	if errors.As(err, &eerr1) {
+		err = sc.handleAuthError(req, res)
+	}
+
 	// add cseq
-	var eerr liberrors.ErrServerCSeqMissing
-	if !errors.As(err, &eerr) {
+	var eerr2 liberrors.ErrServerCSeqMissing
+	if !errors.As(err, &eerr2) {
 		res.Header["CSeq"] = req.Header["CSeq"]
 	}
 
 	// add server
-	res.Header["Server"] = base.HeaderValue{"gortsplib"}
+	res.Header["Server"] = base.HeaderValue{serverHeader}
 
 	if h, ok := sc.s.Handler.(ServerHandlerOnResponse); ok {
 		h.OnResponse(sc, res)

server_test.go

@@ -3,6 +3,7 @@ package gortsplib
 import (
 	"fmt"
 	"net"
+	"net/http"
 	"testing"
 	"time"
 
@@ -13,6 +14,7 @@ import (
 	"github.com/bluenviron/gortsplib/v4/pkg/conn"
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
 	"github.com/bluenviron/gortsplib/v4/pkg/headers"
+	"github.com/bluenviron/gortsplib/v4/pkg/liberrors"
 )
 
 var serverCert = []byte(`-----BEGIN CERTIFICATE-----
@@ -1035,20 +1037,87 @@ func TestServerSessionTeardown(t *testing.T) {
 }
 
 func TestServerAuth(t *testing.T) {
-	nonce, err := auth.GenerateNonce()
-	require.NoError(t, err)
+	for _, method := range []string{"all", "basic", "digest_md5", "digest_sha256"} {
+		t.Run(method, func(t *testing.T) {
+			s := &Server{
+				Handler: &testServerHandler{
+					onAnnounce: func(ctx *ServerHandlerOnAnnounceCtx) (*base.Response, error) {
+						ok := ctx.Conn.VerifyCredentials(ctx.Request, "myuser", "mypass")
+						if !ok {
+							return &base.Response{
+								StatusCode: base.StatusUnauthorized,
+							}, liberrors.ErrServerAuth{}
+						}
 
+						return &base.Response{
+							StatusCode: base.StatusOK,
+						}, nil
+					},
+				},
+				RTSPAddress: "localhost:8554",
+				AuthMethods: func() []auth.VerifyMethod {
+					switch method {
+					case "basic":
+						return []auth.VerifyMethod{auth.VerifyMethodBasic}
+
+					case "digest_md5":
+						return []auth.VerifyMethod{auth.VerifyMethodDigestMD5}
+
+					case "digest_sha256":
+						return []auth.VerifyMethod{auth.VerifyMethodDigestSHA256}
+					}
+					return nil
+				}(),
+			}
+
+			err := s.Start()
+			require.NoError(t, err)
+			defer s.Close()
+
+			nconn, err := net.Dial("tcp", "localhost:8554")
+			require.NoError(t, err)
+			defer nconn.Close()
+			conn := conn.NewConn(nconn)
+
+			medias := []*description.Media{testH264Media}
+
+			req := base.Request{
+				Method: base.Announce,
+				URL:    mustParseURL("rtsp://localhost:8554/teststream"),
+				Header: base.Header{
+					"CSeq":         base.HeaderValue{"1"},
+					"Content-Type": base.HeaderValue{"application/sdp"},
+				},
+				Body: mediasToSDP(medias),
+			}
+
+			res, err := writeReqReadRes(conn, req)
+			require.NoError(t, err)
+			require.Equal(t, base.StatusUnauthorized, res.StatusCode)
+
+			sender, err := auth.NewSender(res.Header["WWW-Authenticate"], "myuser", "mypass")
+			require.NoError(t, err)
+
+			sender.AddAuthorization(&req)
+			res, err = writeReqReadRes(conn, req)
+			require.NoError(t, err)
+			require.Equal(t, base.StatusOK, res.StatusCode)
+		})
+	}
+}
+
+func TestServerAuthFail(t *testing.T) {
 	s := &Server{
 		Handler: &testServerHandler{
+			onConnClose: func(ctx *ServerHandlerOnConnCloseCtx) {
+				require.EqualError(t, ctx.Error, "authentication error")
+			},
 			onAnnounce: func(ctx *ServerHandlerOnAnnounceCtx) (*base.Response, error) {
-				err2 := auth.Verify(ctx.Request, "myuser", "mypass", nil, "IPCAM", nonce)
-				if err2 != nil {
-					return &base.Response{ //nolint:nilerr
-						StatusCode: base.StatusUnauthorized,
-						Header: base.Header{
-							"WWW-Authenticate": auth.GenerateWWWAuthenticate(nil, "IPCAM", nonce),
-						},
-					}, nil
+				ok := ctx.Conn.VerifyCredentials(ctx.Request, "myuser2", "mypass2")
+				if !ok {
+					return &base.Response{
+						StatusCode: http.StatusUnauthorized,
+					}, liberrors.ErrServerAuth{}
 				}
 
 				return &base.Response{
@@ -1059,7 +1128,7 @@ func TestServerAuth(t *testing.T) {
 		RTSPAddress: "localhost:8554",
 	}
 
-	err = s.Start()
+	err := s.Start()
 	require.NoError(t, err)
 	defer s.Close()
 
@@ -1088,7 +1157,11 @@ func TestServerAuth(t *testing.T) {
 	require.NoError(t, err)
 
 	sender.AddAuthorization(&req)
+
 	res, err = writeReqReadRes(conn, req)
 	require.NoError(t, err)
-	require.Equal(t, base.StatusOK, res.StatusCode)
+	require.Equal(t, base.StatusUnauthorized, res.StatusCode)
+
+	_, err = writeReqReadRes(conn, req)
+	require.Error(t, err)
 }