optimisations

cmd/ck-client/ck-client.go

@@ -142,8 +142,8 @@ func main() {
 		log.Fatalf("Failed to establish connection to remote: %v\n", err)
 	}
 
-	obfs := util.MakeObfs(sta.SID)
+	obfs := util.MakeObfs(sta.SID[:16])
-	deobfs := util.MakeDeobfs(sta.SID)
+	deobfs := util.MakeDeobfs(sta.SID[:16])
 	// TODO: where to put obfs deobfs and rtd?
 	sesh := mux.MakeSession(0, initRemoteConn, obfs, deobfs, util.ReadTillDrain)
 

cmd/ck-server/ck-server.go

@@ -9,7 +9,7 @@ import (
 	"net/http"
 	_ "net/http/pprof"
 	"os"
-	"runtime"
+	//"runtime"
 	"strings"
 	"time"
 
@@ -105,7 +105,7 @@ func dispatchConnection(conn net.Conn, sta *server.State) {
 		if sesh = sta.GetSession(arrSID); sesh != nil {
 			sesh.AddConnection(conn)
 		} else {
-			sesh = mux.MakeSession(0, conn, util.MakeObfs(SID), util.MakeDeobfs(SID), util.ReadTillDrain)
+			sesh = mux.MakeSession(0, conn, util.MakeObfs(SID[:16]), util.MakeDeobfs(SID[:16]), util.ReadTillDrain)
 			sta.PutSession(arrSID, sesh)
 		}
 		go func() {
@@ -129,7 +129,6 @@ func dispatchConnection(conn net.Conn, sta *server.State) {
 }
 
 func main() {
-	runtime.SetBlockProfileRate(2)
 	go func() {
 		log.Println(http.ListenAndServe("0.0.0.0:8001", nil))
 	}()

internal/multiplex/frameSorter.go

@@ -62,6 +62,18 @@ func (s *Stream) recvNewFrame() {
 			continue
 		}
 
+		if len(s.sh) == 0 && f.Seq == s.nextRecvSeq {
+			s.sortedBufCh <- f.Payload
+
+			s.nextRecvSeq += 1
+			if s.nextRecvSeq == 0 {
+				// when nextN is wrapped, wrapMode becomes false and rev+1
+				s.rev += 1
+				s.wrapMode = false
+			}
+			continue
+		}
+
 		// For the ease of demonstration, assume seq is uint8, i.e. it wraps around after 255
 		fs := &frameNode{
 			f.Seq,

internal/multiplex/switchboard.go

@@ -3,7 +3,7 @@ package multiplex
 import (
 	"log"
 	"net"
-	//"sort"
+	"sort"
 )
 
 const (
@@ -79,18 +79,18 @@ type sentNotifier struct {
 
 func (ce *connEnclave) send(data []byte) {
 	// TODO: error handling
-	_, err := ce.remoteConn.Write(data)
+	n, err := ce.remoteConn.Write(data)
 	if err != nil {
 		ce.sb.closingCECh <- ce
 		log.Println(err)
 	}
-	/*
+
-		sn := &sentNotifier{
+	sn := &sentNotifier{
-			ce,
+		ce,
-			n,
+		n,
-		}
+	}
-		ce.sb.sentNotifyCh <- sn
+	ce.sb.sentNotifyCh <- sn
-	*/
+
 }
 
 // Dispatcher sends data coming from a stream to a remote connection
@@ -102,11 +102,11 @@ func (sb *switchboard) dispatch() {
 		// dispatCh receives data from stream.Write
 		case data := <-sb.dispatCh:
 			go sb.ces[nextCE%len(sb.ces)].send(data)
-			//sb.ces[0].sendQueue += len(data)
+			sb.ces[0].sendQueue += len(data)
 			nextCE += 1
-		/*case notified := <-sb.sentNotifyCh:
+		case notified := <-sb.sentNotifyCh:
-		notified.ce.sendQueue -= notified.sent
+			notified.ce.sendQueue -= notified.sent
-		sort.Sort(byQ(sb.ces))*/
+			sort.Sort(byQ(sb.ces))
 		case conn := <-sb.newConnCh:
 			log.Println("newConn")
 			newCe := &connEnclave{

internal/util/obfs.go

@@ -37,20 +37,26 @@ func MakeObfs(key []byte) func(*mux.Frame) []byte {
 		iv := make([]byte, 16)
 		io.ReadFull(rand.Reader, iv)
 		cipherheader := AESEncrypt(iv, key, header)
-		obfsed := make([]byte, len(f.Payload)+12+16)
+
-		copy(obfsed[0:16], iv)
+		// Composing final obfsed message
-		copy(obfsed[16:28], cipherheader)
+		// We don't use util.AddRecordLayer here to avoid unnecessary malloc
-		copy(obfsed[28:], f.Payload)
+		obfsed := make([]byte, 5+16+12+len(f.Payload))
-		// obfsed: [iv 16 bytes][cipherheader 12 bytes][payload]
+		obfsed[0] = 0x17
-		ret := AddRecordLayer(obfsed, []byte{0x17}, []byte{0x03, 0x03})
+		obfsed[1] = 0x03
-		return ret
+		obfsed[2] = 0x03
+		binary.BigEndian.PutUint16(obfsed[3:5], uint16(16+12+len(f.Payload)))
+		copy(obfsed[5:21], iv)
+		copy(obfsed[21:33], cipherheader)
+		copy(obfsed[33:], f.Payload)
+		// obfsed: [record layer 5 bytes][iv 16 bytes][cipherheader 12 bytes][payload]
+		return obfsed
 	}
 	return obfs
 }
 
 func MakeDeobfs(key []byte) func([]byte) *mux.Frame {
 	deobfs := func(in []byte) *mux.Frame {
-		peeled := PeelRecordLayer(in)
+		peeled := in[5:]
 		header := AESDecrypt(peeled[0:16], key, peeled[16:28])
 		streamID := binary.BigEndian.Uint32(header[0:4])
 		seq := binary.BigEndian.Uint32(header[4:8])