Remove copy/paste signalling

client/README.md

@@ -12,12 +12,9 @@ ClientTransportPlugin snowflake exec ./client \
 -ice stun:stun.l.google.com:19302
 ```
 
-`-url` should be the URL of a Broker instance. This is required to have
-automated signalling (which is desired in most use cases).
-When omitted, the client uses copy-paste signalling instead.
+`-url` should be the URL of a Broker instance.
 
 `-front` is an optional front domain for the Broker request.
 
 `-ice` is a comma-separated list of ICE servers. These can be STUN or TURN
 servers.
-

client/lib/rendezvous.go

@@ -1,26 +1,20 @@
 // WebRTC rendezvous requires the exchange of SessionDescriptions between
 // peers in order to establish a PeerConnection.
 //
-// This file contains the two methods currently available to Snowflake:
+// This file contains the one method currently available to Snowflake:
 //
 // - Domain-fronted HTTP signaling. The Broker automatically exchange offers
 //   and answers between this client and some remote WebRTC proxy.
-//   (This is the recommended default, enabled via the flags in "torrc".)
-//
-// - Manual copy-paste signaling. User must create a signaling pipe.
-//   (The flags in torrc-manual allow this)
+
 package lib
 
 import (
-	"bufio"
 	"bytes"
 	"errors"
 	"io/ioutil"
 	"log"
 	"net/http"
 	"net/url"
-	"os"
-	"syscall"
 
 	"github.com/keroserene/go-webrtc"
 )
@@ -143,71 +137,3 @@ func (w WebRTCDialer) Catch() (Snowflake, error) {
 	err := connection.Connect()
 	return connection, err
 }
-
-// CopyPasteDialer handles the interaction required to copy-paste the
-// offers and answers.
-// Implements |Tongue| interface to catch snowflakes manually.
-// Supports recovery of connections.
-type CopyPasteDialer struct {
-	webrtcConfig *webrtc.Configuration
-	signal       *os.File
-	current      *WebRTCPeer
-}
-
-func NewCopyPasteDialer(iceServers IceServerList) *CopyPasteDialer {
-	log.Println("No HTTP signaling detected. Using manual copy-paste signaling.")
-	log.Println("Waiting for a \"signal\" pipe...")
-	// This FIFO receives signaling messages.
-	err := syscall.Mkfifo("signal", 0600)
-	if err != nil {
-		if syscall.EEXIST != err.(syscall.Errno) {
-			log.Fatal(err)
-		}
-	}
-	signalFile, err := os.OpenFile("signal", os.O_RDONLY, 0600)
-	if nil != err {
-		log.Fatal(err)
-		return nil
-	}
-	config := webrtc.NewConfiguration(iceServers...)
-	dialer := &CopyPasteDialer{
-		webrtcConfig: config,
-		signal:       signalFile,
-	}
-	go dialer.readSignals()
-	return dialer
-}
-
-// Initialize a WebRTC Peer via manual copy-paste.
-func (d *CopyPasteDialer) Catch() (Snowflake, error) {
-	if nil == d.signal {
-		return nil, errors.New("Cannot copy-paste dial without signal pipe.")
-	}
-	connection := NewWebRTCPeer(d.webrtcConfig, nil)
-	// Must keep track of pending new connection until copy-paste completes.
-	d.current = connection
-	// Outputs SDP offer to log, expecting user to copy-paste to the remote Peer.
-	// Blocks until user pastes back the answer.
-	err := connection.Connect()
-	d.current = nil
-	return connection, err
-}
-
-// Manual copy-paste signalling.
-func (d *CopyPasteDialer) readSignals() {
-	defer d.signal.Close()
-	log.Printf("CopyPasteDialer: reading messages from signal pipe.")
-	s := bufio.NewScanner(d.signal)
-	for s.Scan() {
-		msg := s.Text()
-		sdp := webrtc.DeserializeSessionDescription(msg)
-		if sdp == nil {
-			log.Printf("CopyPasteDialer: ignoring invalid signal message %+q", msg)
-			continue
-		}
-		d.current.answerChannel <- sdp
-	}
-	if err := s.Err(); err != nil {
-		log.Printf("signal FIFO: %s", err)
-	}
-}

client/lib/webrtc.go

@@ -284,14 +284,7 @@ func (c *WebRTCPeer) sendOfferToBroker() {
 // the Broker or signal pipe, then await for the SDP answer.
 func (c *WebRTCPeer) exchangeSDP() error {
 	select {
-	case offer := <-c.offerChannel:
-		// Display for copy-paste when no broker available.
-		if nil == c.broker {
-			log.Printf("Please Copy & Paste the following to the peer:")
-			log.Printf("----------------")
-			log.Printf("\n\n" + offer.Serialize() + "\n\n")
-			log.Printf("----------------")
-		}
+	case <-c.offerChannel:
 	case err := <-c.errorChannel:
 		log.Println("Failed to prepare offer", err)
 		c.Close()

client/snowflake.go

@@ -113,14 +113,11 @@ func main() {
 
 	// Prepare to collect remote WebRTC peers.
 	snowflakes := sf.NewPeers(*max)
-	if "" != *brokerURL {
-		// Use potentially domain-fronting broker to rendezvous.
-		broker := sf.NewBrokerChannel(*brokerURL, *frontDomain, sf.CreateBrokerTransport())
-		snowflakes.Tongue = sf.NewWebRTCDialer(broker, iceServers)
-	} else {
-		// Otherwise, use manual copy and pasting of SDP messages.
-		snowflakes.Tongue = sf.NewCopyPasteDialer(iceServers)
-	}
+
+	// Use potentially domain-fronting broker to rendezvous.
+	broker := sf.NewBrokerChannel(*brokerURL, *frontDomain, sf.CreateBrokerTransport())
+	snowflakes.Tongue = sf.NewWebRTCDialer(broker, iceServers)
+
 	if nil == snowflakes.Tongue {
 		log.Fatal("Unable to prepare rendezvous method.")
 		return

client/torrc-manual

@@ -1,7 +0,0 @@
-UseBridges 1
-DataDirectory datadir
-
-ClientTransportPlugin snowflake exec ./client \
--log snowflake.log
-
-Bridge snowflake 0.0.3.0:1