Commit b5c50b69 authored by Cecylia Bocovich's avatar Cecylia Bocovich
Browse files

Ported snowflake client to work with pion/webrtc

Modified the snowflake client to use pion/webrtc as the webrtc library.
This involved a few small changes to match function signatures as well
as several larger ones:
- OnNegotiationNeeded is no longer supported, so CreateOffer and
SetLocalDescription have been moved to a go routine called after the
other peer connection callbacks are set
- We need our own deserialize/serialize functions
- We need to use a SettingEngine in order to access the
OnICEGatheringStateChange callback
parent 0428797e
......@@ -52,5 +52,5 @@ type SocksConnector interface {
// Interface for the Snowflake's transport. (Typically just webrtc.DataChannel)
type SnowflakeDataChannel interface {
io.Closer
Send([]byte)
Send([]byte) error
}
......@@ -8,7 +8,7 @@ import (
"net/http"
"testing"
"github.com/keroserene/go-webrtc"
"github.com/pion/webrtc"
. "github.com/smartystreets/goconvey/convey"
)
......@@ -17,9 +17,10 @@ type MockDataChannel struct {
done chan bool
}
func (m *MockDataChannel) Send(data []byte) {
func (m *MockDataChannel) Send(data []byte) error {
m.destination.Write(data)
m.done <- true
return nil
}
func (*MockDataChannel) Close() error { return nil }
......@@ -217,11 +218,11 @@ func TestSnowflakeClient(t *testing.T) {
c.offerChannel = make(chan *webrtc.SessionDescription, 1)
c.answerChannel = make(chan *webrtc.SessionDescription, 1)
c.config = webrtc.NewConfiguration()
c.config = &webrtc.Configuration{}
c.preparePeerConnection()
c.offerChannel <- nil
answer := webrtc.DeserializeSessionDescription(
answer := deserializeSessionDescription(
`{"type":"answer","sdp":""}`)
c.answerChannel <- answer
c.exchangeSDP()
......@@ -264,12 +265,11 @@ func TestSnowflakeClient(t *testing.T) {
})
Convey("Rendezvous", t, func() {
webrtc.SetLoggingVerbosity(0)
transport := &MockTransport{
http.StatusOK,
[]byte(`{"type":"answer","sdp":"fake"}`),
}
fakeOffer := webrtc.DeserializeSessionDescription("test")
fakeOffer := deserializeSessionDescription(`{"type":"offer","sdp":"test"}`)
Convey("Construct BrokerChannel with no front domain", func() {
b := NewBrokerChannel("test.broker", "", transport)
......@@ -291,7 +291,7 @@ func TestSnowflakeClient(t *testing.T) {
answer, err := b.Negotiate(fakeOffer)
So(err, ShouldBeNil)
So(answer, ShouldNotBeNil)
So(answer.Sdp, ShouldResemble, "fake")
So(answer.SDP, ShouldResemble, "fake")
})
Convey("BrokerChannel.Negotiate fails with 503", func() {
......
......@@ -17,7 +17,7 @@ import (
"net/http"
"net/url"
"github.com/keroserene/go-webrtc"
"github.com/pion/webrtc"
)
const (
......@@ -84,7 +84,7 @@ func (bc *BrokerChannel) Negotiate(offer *webrtc.SessionDescription) (
*webrtc.SessionDescription, error) {
log.Println("Negotiating via BrokerChannel...\nTarget URL: ",
bc.Host, "\nFront URL: ", bc.url.Host)
data := bytes.NewReader([]byte(offer.Serialize()))
data := bytes.NewReader([]byte(serializeSessionDescription(offer)))
// Suffix with broker's client registration handler.
clientURL := bc.url.ResolveReference(&url.URL{Path: "client"})
request, err := http.NewRequest("POST", clientURL.String(), data)
......@@ -107,7 +107,7 @@ func (bc *BrokerChannel) Negotiate(offer *webrtc.SessionDescription) (
if nil != err {
return nil, err
}
answer := webrtc.DeserializeSessionDescription(string(body))
answer := deserializeSessionDescription(string(body))
return answer, nil
case http.StatusServiceUnavailable:
......@@ -126,15 +126,18 @@ type WebRTCDialer struct {
}
func NewWebRTCDialer(
broker *BrokerChannel, iceServers IceServerList) *WebRTCDialer {
config := webrtc.NewConfiguration(iceServers...)
if nil == config {
log.Println("Unable to prepare WebRTC configuration.")
return nil
broker *BrokerChannel, iceServers []webrtc.ICEServer) *WebRTCDialer {
var config webrtc.Configuration
if iceServers == nil {
config = webrtc.Configuration{
ICEServers: iceServers,
}
} else {
config = webrtc.Configuration{}
}
return &WebRTCDialer{
BrokerChannel: broker,
webrtcConfig: config,
webrtcConfig: &config,
}
}
......
package lib
import (
"fmt"
"encoding/json"
"log"
"time"
"github.com/keroserene/go-webrtc"
"github.com/pion/webrtc"
)
const (
LogTimeInterval = 5
)
type IceServerList []webrtc.ConfigurationOption
func (i *IceServerList) String() string {
return fmt.Sprint(*i)
}
type BytesLogger interface {
Log()
AddOutbound(int)
......@@ -93,3 +87,52 @@ func (b *BytesSyncLogger) AddInbound(amount int) {
}
b.InboundChan <- amount
}
func deserializeSessionDescription(msg string) *webrtc.SessionDescription {
var parsed map[string]interface{}
err := json.Unmarshal([]byte(msg), &parsed)
if nil != err {
log.Println(err)
return nil
}
if _, ok := parsed["type"]; !ok {
log.Println("Cannot deserialize SessionDescription without type field.")
return nil
}
if _, ok := parsed["sdp"]; !ok {
log.Println("Cannot deserialize SessionDescription without sdp field.")
return nil
}
var stype webrtc.SDPType
switch parsed["type"].(string) {
default:
log.Println("Unknown SDP type")
return nil
case "offer":
stype = webrtc.SDPTypeOffer
case "pranswer":
stype = webrtc.SDPTypePranswer
case "answer":
stype = webrtc.SDPTypeAnswer
case "rollback":
stype = webrtc.SDPTypeRollback
}
if err != nil {
log.Println(err)
return nil
}
return &webrtc.SessionDescription{
Type: stype,
SDP: parsed["sdp"].(string),
}
}
func serializeSessionDescription(desc *webrtc.SessionDescription) string {
bytes, err := json.Marshal(*desc)
if nil != err {
log.Println(err)
return ""
}
return string(bytes)
}
......@@ -9,7 +9,7 @@ import (
"time"
"github.com/dchest/uniuri"
"github.com/keroserene/go-webrtc"
"github.com/pion/webrtc"
)
// Remote WebRTC peer.
......@@ -151,48 +151,54 @@ func (c *WebRTCPeer) Connect() error {
// Create and prepare callbacks on a new WebRTC PeerConnection.
func (c *WebRTCPeer) preparePeerConnection() error {
if nil != c.pc {
c.pc.Destroy()
c.pc.Close()
c.pc = nil
}
pc, err := webrtc.NewPeerConnection(c.config)
s := webrtc.SettingEngine{}
s.SetTrickle(true)
api := webrtc.NewAPI(webrtc.WithSettingEngine(s))
pc, err := api.NewPeerConnection(*c.config)
if err != nil {
log.Printf("NewPeerConnection ERROR: %s", err)
return err
}
// Prepare PeerConnection callbacks.
pc.OnNegotiationNeeded = func() {
log.Println("WebRTC: OnNegotiationNeeded")
go func() {
offer, err := pc.CreateOffer()
// TODO: Potentially timeout and retry if ICE isn't working.
if err != nil {
c.errorChannel <- err
return
}
err = pc.SetLocalDescription(offer)
if err != nil {
c.errorChannel <- err
return
}
}()
}
// Allow candidates to accumulate until IceGatheringStateComplete.
pc.OnIceCandidate = func(candidate webrtc.IceCandidate) {
log.Printf(candidate.Candidate)
}
pc.OnIceGatheringStateChange = func(state webrtc.IceGatheringState) {
if state == webrtc.IceGatheringStateComplete {
log.Printf("WebRTC: IceGatheringStateComplete")
// Allow candidates to accumulate until ICEGatheringStateComplete.
pc.OnICECandidate(func(candidate *webrtc.ICECandidate) {
if candidate == nil {
log.Printf("WebRTC: Done gathering candidates")
} else {
log.Printf("WebRTC: Got ICE candidate: %s", candidate.String())
}
})
pc.OnICEGatheringStateChange(func(state webrtc.ICEGathererState) {
if state == webrtc.ICEGathererStateComplete {
log.Println("WebRTC: ICEGatheringStateComplete")
c.offerChannel <- pc.LocalDescription()
}
}
})
// This callback is not expected, as the Client initiates the creation
// of the data channel, not the remote peer.
pc.OnDataChannel = func(channel *webrtc.DataChannel) {
pc.OnDataChannel(func(channel *webrtc.DataChannel) {
log.Println("OnDataChannel")
panic("Unexpected OnDataChannel!")
}
})
c.pc = pc
go func() {
offer, err := pc.CreateOffer(nil)
// TODO: Potentially timeout and retry if ICE isn't working.
if err != nil {
c.errorChannel <- err
return
}
log.Println("WebRTC: Created offer")
err = pc.SetLocalDescription(offer)
if err != nil {
c.errorChannel <- err
return
}
log.Println("WebRTC: Set local description")
}()
log.Println("WebRTC: PeerConnection created.")
return nil
}
......@@ -204,7 +210,11 @@ func (c *WebRTCPeer) establishDataChannel() error {
if c.transport != nil {
panic("Unexpected datachannel already exists!")
}
dc, err := c.pc.CreateDataChannel(c.id)
ordered := true
dataChannelOptions := &webrtc.DataChannelInit{
Ordered: &ordered,
}
dc, err := c.pc.CreateDataChannel(c.id, dataChannelOptions)
// Triggers "OnNegotiationNeeded" on the PeerConnection, which will prepare
// an SDP offer while other goroutines operating on this struct handle the
// signaling. Eventually fires "OnOpen".
......@@ -212,7 +222,7 @@ func (c *WebRTCPeer) establishDataChannel() error {
log.Printf("CreateDataChannel ERROR: %s", err)
return err
}
dc.OnOpen = func() {
dc.OnOpen(func() {
c.lock.Lock()
defer c.lock.Unlock()
log.Println("WebRTC: DataChannel.OnOpen")
......@@ -227,8 +237,8 @@ func (c *WebRTCPeer) establishDataChannel() error {
}
// Then enable the datachannel.
c.transport = dc
}
dc.OnClose = func() {
})
dc.OnClose(func() {
c.lock.Lock()
// Future writes will go to the buffer until a new DataChannel is available.
if nil == c.transport {
......@@ -241,29 +251,29 @@ func (c *WebRTCPeer) establishDataChannel() error {
// Disable the DataChannel as a write destination.
log.Println("WebRTC: DataChannel.OnClose [remotely]")
c.transport = nil
c.pc.DeleteDataChannel(dc)
dc.Close()
// Unlock before Close'ing, since it calls cleanup and asks for the
// lock to check if the transport needs to be be deleted.
c.lock.Unlock()
c.Close()
}
dc.OnMessage = func(msg []byte) {
if len(msg) <= 0 {
})
dc.OnMessage(func(msg webrtc.DataChannelMessage) {
if len(msg.Data) <= 0 {
log.Println("0 length message---")
}
c.BytesLogger.AddInbound(len(msg))
n, err := c.writePipe.Write(msg)
c.BytesLogger.AddInbound(len(msg.Data))
n, err := c.writePipe.Write(msg.Data)
if err != nil {
// TODO: Maybe shouldn't actually close.
log.Println("Error writing to SOCKS pipe")
c.writePipe.CloseWithError(err)
}
if n != len(msg) {
if n != len(msg.Data) {
log.Println("Error: short write")
panic("short write")
}
c.lastReceive = time.Now()
}
})
log.Println("WebRTC: DataChannel created.")
return nil
}
......@@ -304,7 +314,7 @@ func (c *WebRTCPeer) exchangeSDP() error {
}
}
log.Printf("Received Answer.\n")
err := c.pc.SetRemoteDescription(answer)
err := c.pc.SetRemoteDescription(*answer)
if nil != err {
log.Println("WebRTC: Unable to SetRemoteDescription:", err)
return err
......@@ -342,13 +352,13 @@ func (c *WebRTCPeer) cleanup() {
if c.pc == nil {
panic("DataChannel w/o PeerConnection, not good.")
}
c.pc.DeleteDataChannel(dataChannel.(*webrtc.DataChannel))
dataChannel.(*webrtc.DataChannel).Close()
} else {
c.lock.Unlock()
}
if nil != c.pc {
log.Printf("WebRTC: closing PeerConnection")
err := c.pc.Destroy()
err := c.pc.Close()
if nil != err {
log.Printf("Error closing peerconnection...")
}
......
......@@ -17,7 +17,7 @@ import (
"git.torproject.org/pluggable-transports/goptlib.git"
sf "git.torproject.org/pluggable-transports/snowflake.git/client/lib"
"git.torproject.org/pluggable-transports/snowflake.git/common/safelog"
"github.com/keroserene/go-webrtc"
"github.com/pion/webrtc"
)
const (
......@@ -65,6 +65,25 @@ func socksAcceptLoop(ln *pt.SocksListener, snowflakes sf.SnowflakeCollector) err
}
}
//s is a comma-separated list of ICE server URLs
func parseIceServers(s string) []webrtc.ICEServer {
var servers []webrtc.ICEServer
log.Println(s)
s = strings.TrimSpace(s)
if len(s) == 0 {
return nil
}
urls := strings.Split(s, ",")
log.Printf("Using ICE Servers:")
for _, url := range urls {
log.Printf("url: %s", url)
servers = append(servers, webrtc.ICEServer{
URLs: []string{url},
})
}
return servers
}
func main() {
iceServersCommas := flag.String("ice", "", "comma-separated list of ICE servers")
brokerURL := flag.String("url", "", "URL of signaling broker")
......@@ -75,7 +94,6 @@ func main() {
"capacity for number of multiplexed WebRTC peers")
flag.Parse()
webrtc.SetLoggingVerbosity(1)
log.SetFlags(log.LstdFlags | log.LUTC)
// Don't write to stderr; versions of tor earlier than about
......@@ -105,11 +123,7 @@ func main() {
log.Println("\n\n\n --- Starting Snowflake Client ---")
var iceServers sf.IceServerList
if len(strings.TrimSpace(*iceServersCommas)) > 0 {
option := webrtc.OptionIceServer(*iceServersCommas)
iceServers = append(iceServers, option)
}
iceServers := parseIceServers(*iceServersCommas)
// Prepare to collect remote WebRTC peers.
snowflakes := sf.NewPeers(*max)
......
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