archives/snowflake
2
0
Fork 0
mirror of https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowflake.git synced 2025-10-13 20:11:19 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

Add synchronization around destroying DataChannels and PeerConnections

Browse source 
From https://trac.torproject.org/projects/tor/ticket/21312#comment:33
This commit is contained in:
Arlo Breault 2018-03-14 13:35:39 -04:00
parent 40bf7664d4
commit 1114acbcb4
3 changed files with 54 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

17
proxy-go/snowflake.go
View file

@ -62,6 +62,9 @@ type webRTCConn struct {
dc *webrtc.DataChannel
pc *webrtc.PeerConnection
pr *io.PipeReader
lock sync.Mutex // Synchronization for DataChannel destruction
once sync.Once // Synchronization for PeerConnection destruction
}
func (c *webRTCConn) Read(b []byte) (int, error) {
@ -69,6 +72,8 @@ func (c *webRTCConn) Read(b []byte) (int, error) {
}
func (c *webRTCConn) Write(b []byte) (int, error) {
c.lock.Lock()
defer c.lock.Unlock()
// log.Printf("webrtc Write %d %+q", len(b), string(b))
log.Printf("Write %d bytes --> WebRTC", len(b))
if c.dc != nil {
@ -77,8 +82,11 @@ func (c *webRTCConn) Write(b []byte) (int, error) {
return len(b), nil
}
func (c *webRTCConn) Close() error {
return c.pc.Destroy()
func (c *webRTCConn) Close() (err error) {
c.once.Do(func() {
err = c.pc.Destroy()
})
return
}
func (c *webRTCConn) LocalAddr() net.Addr {
@ -255,17 +263,18 @@ func makePeerConnectionFromOffer(sdp *webrtc.SessionDescription, config *webrtc.
log.Println("OnDataChannel")
pr, pw := io.Pipe()
conn := &webRTCConn{pc: pc, dc: dc, pr: pr}
dc.OnOpen = func() {
log.Println("OnOpen channel")
}
dc.OnClose = func() {
conn.lock.Lock()
defer conn.lock.Unlock()
log.Println("OnClose channel")
pw.Close()
conn.dc = nil
pc.DeleteDataChannel(dc)
pw.Close()
}
dc.OnMessage = func(msg []byte) {
log.Printf("OnMessage <--- %d bytes", len(msg))