Support ICE servers auth (#920)

* change ICEServers type in config to Pion-defined type
This allows specifying credentials for access to servers,
in particular TURN servers.

* add legacy support for ICEServers as []string

client.go

@@ -35,6 +35,7 @@ import (
 	"github.com/dustin/go-humanize"
 	gbtree "github.com/google/btree"
 	"github.com/pion/datachannel"
+	"github.com/pion/webrtc/v3"
 
 	"github.com/anacrolix/torrent/bencode"
 	"github.com/anacrolix/torrent/internal/check"
@@ -310,6 +311,13 @@ func NewClient(cfg *ClientConfig) (cl *Client, err error) {
 		}
 	}
 
+	var ICEServers []webrtc.ICEServer
+	if cl.config.ICEServerList != nil {
+		ICEServers = cl.config.ICEServerList
+	} else if cl.config.ICEServers != nil {
+		ICEServers = []webrtc.ICEServer{{URLs: cl.config.ICEServers}}
+	}
+
 	cl.websocketTrackers = websocketTrackers{
 		PeerId: cl.peerID,
 		Logger: cl.logger,
@@ -328,7 +336,7 @@ func NewClient(cfg *ClientConfig) (cl *Client, err error) {
 		},
 		Proxy:                      cl.config.HTTPProxy,
 		WebsocketTrackerHttpHeader: cl.config.WebsocketTrackerHttpHeader,
-		ICEServers:                 cl.config.ICEServers,
+		ICEServers:                 ICEServers,
 		DialContext:                cl.config.TrackerDialContext,
 		OnConn: func(dc datachannel.ReadWriteCloser, dcc webtorrent.DataChannelContext) {
 			cl.lock()
@@ -1843,6 +1851,16 @@ func (cl *Client) String() string {
 	return fmt.Sprintf("<%[1]T %[1]p>", cl)
 }
 
+func (cl *Client) ICEServers() []webrtc.ICEServer {
+	var ICEServers []webrtc.ICEServer
+	if cl.config.ICEServerList != nil {
+		ICEServers = cl.config.ICEServerList
+	} else if cl.config.ICEServers != nil {
+		ICEServers = []webrtc.ICEServer{{URLs: cl.config.ICEServers}}
+	}
+	return ICEServers
+}
+
 // Returns connection-level aggregate connStats at the Client level. See the comment on
 // TorrentStats.ConnStats.
 func (cl *Client) ConnStats() ConnStats {

config.go

@@ -11,6 +11,7 @@ import (
 	"github.com/anacrolix/dht/v2/krpc"
 	"github.com/anacrolix/log"
 	"github.com/anacrolix/missinggo/v2"
+	"github.com/pion/webrtc/v3"
 	"golang.org/x/time/rate"
 
 	"github.com/anacrolix/torrent/iplist"
@@ -183,8 +184,13 @@ type ClientConfig struct {
 
 	Callbacks Callbacks
 
-	// ICEServers defines a slice describing servers available to be used by
+	// ICEServerList defines a slice describing servers available to be used by
 	// ICE, such as STUN and TURN servers.
+	ICEServerList []webrtc.ICEServer
+
+	// Deprecated. ICEServers does not support server authentication and therefore
+	// it cannot be used with most TURN servers. Use ICEServerList instead.
+	// ICEServers is kept for legacy support.
 	ICEServers []string
 
 	DialRateLimiter *rate.Limiter

go.sum

@@ -109,8 +109,6 @@ github.com/anacrolix/multiless v0.3.0 h1:5Bu0DZncjE4e06b9r1Ap2tUY4Au0NToBP5RpuEn
 github.com/anacrolix/multiless v0.3.0/go.mod h1:TrCLEZfIDbMVfLoQt5tOoiBS/uq4y8+ojuEVVvTNPX4=
 github.com/anacrolix/possum/go v0.1.1-0.20240309232535-7d660fa365f8 h1:XDKUI9RHyhyfGXVXb/4N+l5kGo5jQITrrbF7EZPLuak=
 github.com/anacrolix/possum/go v0.1.1-0.20240309232535-7d660fa365f8/go.mod h1:pw5HEMBSiL+otYzHe4q5jGaVuy5unl+Mt4Bx6SDemW8=
-github.com/anacrolix/squirrel v0.6.0 h1:ovfWW42wcGzrVYYI9s56pEYzfeTwtXxCCvSd+KwvUEA=
-github.com/anacrolix/squirrel v0.6.0/go.mod h1:60vdNPUbK1jYWePp39Wqn9whHm12Yb9JEuwOXzLMDuY=
 github.com/anacrolix/squirrel v0.6.4 h1:K6ABRMCms0xwpEIdY3kAaDBUqiUeUYCKLKI0yHTr9IQ=
 github.com/anacrolix/squirrel v0.6.4/go.mod h1:0kFVjOLMOKVOet6ja2ac1vTOrqVbLj2zy2Fjp7+dkE8=
 github.com/anacrolix/stm v0.2.0/go.mod h1:zoVQRvSiGjGoTmbM0vSLIiaKjWtNPeTvXUSdJQA4hsg=

webtorrent/tracker-client.go

@@ -43,7 +43,7 @@ type TrackerClient struct {
 	pingTicker     *time.Ticker
 
 	WebsocketTrackerHttpHeader func() http.Header
-	ICEServers                 []string
+	ICEServers                 []webrtc.ICEServer
 }
 
 func (me *TrackerClient) Stats() TrackerClientStats {

webtorrent/transport.go

@@ -48,12 +48,12 @@ func (me *wrappedPeerConnection) Close() error {
 	return err
 }
 
-func newPeerConnection(logger log.Logger, iceServers []string) (*wrappedPeerConnection, error) {
+func newPeerConnection(logger log.Logger, iceServers []webrtc.ICEServer) (*wrappedPeerConnection, error) {
 	newPeerConnectionMu.Lock()
 	defer newPeerConnectionMu.Unlock()
 	ctx, span := otel.Tracer(tracerName).Start(context.Background(), "PeerConnection")
 
-	pcConfig := webrtc.Configuration{ICEServers: []webrtc.ICEServer{{URLs: iceServers}}}
+	pcConfig := webrtc.Configuration{ICEServers: iceServers}
 
 	pc, err := api.NewPeerConnection(pcConfig)
 	if err != nil {

wstracker.go

@@ -11,6 +11,7 @@ import (
 	"github.com/anacrolix/log"
 	"github.com/gorilla/websocket"
 	"github.com/pion/datachannel"
+	"github.com/pion/webrtc/v3"
 
 	"github.com/anacrolix/torrent/tracker"
 	httpTracker "github.com/anacrolix/torrent/tracker/http"
@@ -45,7 +46,7 @@ type websocketTrackers struct {
 	Proxy                      httpTracker.ProxyFunc
 	DialContext                func(ctx context.Context, network, addr string) (net.Conn, error)
 	WebsocketTrackerHttpHeader func() netHttp.Header
-	ICEServers                 []string
+	ICEServers                 []webrtc.ICEServer
 }
 
 func (me *websocketTrackers) Get(url string, infoHash [20]byte) (*webtorrent.TrackerClient, func()) {