commit ac9d49b8727b953c12a76e3645fe71a9ec3aab75
Author: Serene H <git(a)keroserene.net>
Date: Mon Aug 1 12:17:28 2016 -0700
ensure closing stale remotes from the client side
---
client/snowflake.go | 3 +-
client/webrtc.go | 81 ++++++++++++++++++++++++++++++++++-------------------
2 files changed, 54 insertions(+), 30 deletions(-)
diff --git a/client/snowflake.go b/client/snowflake.go
index 8dfa390..75e999f 100644
--- a/client/snowflake.go
+++ b/client/snowflake.go
@@ -20,6 +20,7 @@ import (
const (
ReconnectTimeout = 10
DefaultSnowflakeCapacity = 1
+ SnowflakeTimeout = 30
)
// When a connection handler starts, +1 is written to this channel; when it
@@ -81,7 +82,7 @@ func handler(socks SocksConnector, snowflakes SnowflakeCollector) error {
return errors.New("handler: Received invalid Snowflake")
}
defer socks.Close()
- defer snowflake.Reset()
+ defer snowflake.Close()
log.Println("---- Handler: snowflake assigned ----")
err := socks.Grant(&net.TCPAddr{IP: net.IPv4zero, Port: 0})
if err != nil {
diff --git a/client/webrtc.go b/client/webrtc.go
index 1f7ac00..0492466 100644
--- a/client/webrtc.go
+++ b/client/webrtc.go
@@ -29,6 +29,7 @@ type WebRTCPeer struct {
errorChannel chan error
recvPipe *io.PipeReader
writePipe *io.PipeWriter
+ lastReceive time.Time
buffer bytes.Buffer
reset chan struct{}
@@ -37,6 +38,28 @@ type WebRTCPeer struct {
BytesLogger
}
+// Construct a WebRTC PeerConnection.
+func NewWebRTCPeer(config *webrtc.Configuration,
+ broker *BrokerChannel) *WebRTCPeer {
+ connection := new(WebRTCPeer)
+ connection.id = "snowflake-" + uniuri.New()
+ connection.config = config
+ connection.broker = broker
+ connection.offerChannel = make(chan *webrtc.SessionDescription, 1)
+ connection.answerChannel = make(chan *webrtc.SessionDescription, 1)
+ // Error channel is mostly for reporting during the initial SDP offer
+ // creation & local description setting, which happens asynchronously.
+ connection.errorChannel = make(chan error, 1)
+ connection.reset = make(chan struct{}, 1)
+
+ // Override with something that's not NullLogger to have real logging.
+ connection.BytesLogger = &BytesNullLogger{}
+
+ // Pipes remain the same even when DataChannel gets switched.
+ connection.recvPipe, connection.writePipe = io.Pipe()
+ return connection
+}
+
// Read bytes from local SOCKS.
// As part of |io.ReadWriter|
func (c *WebRTCPeer) Read(b []byte) (int, error) {
@@ -47,6 +70,7 @@ func (c *WebRTCPeer) Read(b []byte) (int, error) {
// As part of |io.ReadWriter|
func (c *WebRTCPeer) Write(b []byte) (int, error) {
c.BytesLogger.AddOutbound(len(b))
+ // TODO: Buffering could be improved / separated out of WebRTCPeer.
if nil == c.transport {
log.Printf("Buffered %d bytes --> WebRTC", len(b))
c.buffer.Write(b)
@@ -61,45 +85,42 @@ func (c *WebRTCPeer) Close() error {
if c.closed { // Skip if already closed.
return nil
}
- log.Printf("WebRTC: Closing")
- c.cleanup()
// Mark for deletion.
c.closed = true
+ c.cleanup()
+ c.Reset()
+ log.Printf("WebRTC: Closing")
return nil
}
// As part of |Resetter|
func (c *WebRTCPeer) Reset() {
- c.Close()
- go func() {
- c.reset <- struct{}{}
- log.Println("WebRTC resetting...")
- }()
+ if nil == c.reset {
+ return
+ }
+ c.reset <- struct{}{}
}
// As part of |Resetter|
func (c *WebRTCPeer) WaitForReset() { <-c.reset }
-// Construct a WebRTC PeerConnection.
-func NewWebRTCPeer(config *webrtc.Configuration,
- broker *BrokerChannel) *WebRTCPeer {
- connection := new(WebRTCPeer)
- connection.id = "snowflake-" + uniuri.New()
- connection.config = config
- connection.broker = broker
- connection.offerChannel = make(chan *webrtc.SessionDescription, 1)
- connection.answerChannel = make(chan *webrtc.SessionDescription, 1)
- // Error channel is mostly for reporting during the initial SDP offer
- // creation & local description setting, which happens asynchronously.
- connection.errorChannel = make(chan error, 1)
- connection.reset = make(chan struct{}, 1)
-
- // Override with something that's not NullLogger to have real logging.
- connection.BytesLogger = &BytesNullLogger{}
-
- // Pipes remain the same even when DataChannel gets switched.
- connection.recvPipe, connection.writePipe = io.Pipe()
- return connection
+// Prevent long-lived broken remotes.
+// Should also update the DataChannel in underlying go-webrtc's to make Closes
+// more immediate / responsive.
+func (c *WebRTCPeer) checkForStaleness() {
+ c.lastReceive = time.Now()
+ for {
+ if c.closed {
+ return
+ }
+ if time.Since(c.lastReceive).Seconds() > SnowflakeTimeout {
+ log.Println("WebRTC: No messages received for", SnowflakeTimeout,
+ "seconds -- closing stale connection.")
+ c.Close()
+ return
+ }
+ <-time.After(time.Second)
+ }
}
// As part of |Connector| interface.
@@ -119,6 +140,7 @@ func (c *WebRTCPeer) Connect() error {
if err != nil {
return err
}
+ go c.checkForStaleness()
return nil
}
@@ -208,7 +230,7 @@ func (c *WebRTCPeer) establishDataChannel() error {
// Disable the DataChannel as a write destination.
log.Println("WebRTC: DataChannel.OnClose [remotely]")
c.transport = nil
- c.Reset()
+ c.Close()
}
dc.OnMessage = func(msg []byte) {
if len(msg) <= 0 {
@@ -225,6 +247,7 @@ func (c *WebRTCPeer) establishDataChannel() error {
log.Println("Error: short write")
panic("short write")
}
+ c.lastReceive = time.Now()
}
log.Println("WebRTC: DataChannel created.")
return nil
@@ -257,7 +280,7 @@ func (c *WebRTCPeer) exchangeSDP() error {
}
case err := <-c.errorChannel:
log.Println("Failed to prepare offer", err)
- c.Reset()
+ c.Close()
return err
}
// Keep trying the same offer until a valid answer arrives.