Fix #61

internal/multiplex/blackhole_test.go

@@ -0,0 +1,41 @@
+package multiplex
+
+import (
+	"bufio"
+	"io"
+	"io/ioutil"
+	"net"
+	"time"
+)
+
+type blackhole struct {
+	hole   *bufio.Writer
+	closer chan int
+}
+
+func newBlackHole() *blackhole {
+	return &blackhole{
+		hole:   bufio.NewWriter(ioutil.Discard),
+		closer: make(chan int),
+	}
+}
+func (b *blackhole) Read([]byte) (int, error) {
+	<-b.closer
+	return 0, io.EOF
+}
+func (b *blackhole) Write(in []byte) (int, error) { return b.hole.Write(in) }
+func (b *blackhole) Close() error {
+	b.closer <- 1
+	return nil
+}
+func (b *blackhole) LocalAddr() net.Addr {
+	ret, _ := net.ResolveTCPAddr("tcp", "127.0.0.1")
+	return ret
+}
+func (b *blackhole) RemoteAddr() net.Addr {
+	ret, _ := net.ResolveTCPAddr("tcp", "127.0.0.1")
+	return ret
+}
+func (b *blackhole) SetDeadline(t time.Time) error      { return nil }
+func (b *blackhole) SetReadDeadline(t time.Time) error  { return nil }
+func (b *blackhole) SetWriteDeadline(t time.Time) error { return nil }

internal/multiplex/stream_test.go

@@ -1,10 +1,8 @@
 package multiplex
 
 import (
-	"bufio"
 	"bytes"
 	"github.com/cbeuw/Cloak/internal/util"
-	"io/ioutil"
 	"math/rand"
 	"net"
 	"testing"
@@ -25,29 +23,6 @@ func setupSesh(unordered bool) *Session {
 	return MakeSession(0, seshConfig)
 }
 
-type blackhole struct {
-	hole *bufio.Writer
-}
-
-func newBlackHole() *blackhole { return &blackhole{hole: bufio.NewWriter(ioutil.Discard)} }
-func (b *blackhole) Read([]byte) (int, error) {
-	time.Sleep(1 * time.Hour)
-	return 0, nil
-}
-func (b *blackhole) Write(in []byte) (int, error) { return b.hole.Write(in) }
-func (b *blackhole) Close() error                 { return nil }
-func (b *blackhole) LocalAddr() net.Addr {
-	ret, _ := net.ResolveTCPAddr("tcp", "127.0.0.1")
-	return ret
-}
-func (b *blackhole) RemoteAddr() net.Addr {
-	ret, _ := net.ResolveTCPAddr("tcp", "127.0.0.1")
-	return ret
-}
-func (b *blackhole) SetDeadline(t time.Time) error      { return nil }
-func (b *blackhole) SetReadDeadline(t time.Time) error  { return nil }
-func (b *blackhole) SetWriteDeadline(t time.Time) error { return nil }
-
 func BenchmarkStream_Write_Ordered(b *testing.B) {
 	const PAYLOAD_LEN = 1000
 	hole := newBlackHole()

internal/multiplex/switchboard.go

@@ -72,15 +72,22 @@ func (sb *switchboard) send(data []byte, connId *uint32) (n int, err error) {
 	sb.connsM.RLock()
 	defer sb.connsM.RUnlock()
 	if sb.strategy == UNIFORM_SPREAD {
-		randConnId := rand.Intn(len(sb.conns))
+		if atomic.LoadUint32(&sb.broken) == 1 || len(sb.conns) == 0 {
-		conn, ok := sb.conns[uint32(randConnId)]
-		if !ok {
 			return 0, errBrokenSwitchboard
-		} else {
-			n, err = conn.Write(data)
-			sb.AddTx(int64(n))
-			return
 		}
+
+		r := rand.Intn(len(sb.conns))
+		var c int
+		for newConnId := range sb.conns {
+			if r == c {
+				conn, _ := sb.conns[newConnId]
+				n, err = conn.Write(data)
+				sb.AddTx(int64(n))
+				return
+			}
+			c++
+		}
+		return 0, errBrokenSwitchboard
 	} else {
 		var conn net.Conn
 		conn, ok := sb.conns[*connId]

internal/multiplex/switchboard_test.go

@@ -6,15 +6,79 @@ import (
 	"testing"
 )
 
+func TestSwitchboard_Send(t *testing.T) {
+	doTest := func(seshConfig *SessionConfig) {
+		sesh := MakeSession(0, seshConfig)
+		hole0 := newBlackHole()
+		sesh.sb.addConn(hole0)
+		connId, err := sesh.sb.assignRandomConn()
+		if err != nil {
+			t.Error("failed to get a random conn", err)
+			return
+		}
+		data := make([]byte, 1000)
+		rand.Read(data)
+		_, err = sesh.sb.send(data, &connId)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+
+		hole1 := newBlackHole()
+		sesh.sb.addConn(hole1)
+		connId, err = sesh.sb.assignRandomConn()
+		if err != nil {
+			t.Error("failed to get a random conn", err)
+			return
+		}
+		_, err = sesh.sb.send(data, &connId)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+
+		hole0.Close()
+
+		connId, err = sesh.sb.assignRandomConn()
+		if err != nil {
+			t.Error("failed to get a random conn", err)
+			return
+		}
+		_, err = sesh.sb.send(data, &connId)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+	}
+
+	t.Run("Ordered", func(t *testing.T) {
+		seshConfig := &SessionConfig{
+			Obfuscator: nil,
+			Valve:      nil,
+			UnitRead:   util.ReadTLS,
+			Unordered:  false,
+		}
+		doTest(seshConfig)
+	})
+	t.Run("Unordered", func(t *testing.T) {
+		seshConfig := &SessionConfig{
+			Obfuscator: nil,
+			Valve:      nil,
+			UnitRead:   util.ReadTLS,
+			Unordered:  true,
+		}
+		doTest(seshConfig)
+	})
+}
+
 func BenchmarkSwitchboard_Send(b *testing.B) {
+	hole := newBlackHole()
 	seshConfig := &SessionConfig{
 		Obfuscator: nil,
 		Valve:      nil,
 		UnitRead:   util.ReadTLS,
 	}
 	sesh := MakeSession(0, seshConfig)
-
-	hole := newBlackHole()
 	sesh.sb.addConn(hole)
 	connId, err := sesh.sb.assignRandomConn()
 	if err != nil {