Merge pull request #1095 from tendermint/804-p2p-issues

[p2p] Pong Timeout

p2p/conn/connection.go

@@ -2,6 +2,7 @@ package conn
 
 import (
 	"bufio"
+	"errors"
 	"fmt"
 	"io"
 	"math"
@@ -21,7 +22,6 @@ const (
 	minReadBufferSize  = 1024
 	minWriteBufferSize = 65536
 	updateStats        = 2 * time.Second
-	pingTimeout        = 40 * time.Second
 
 	// some of these defaults are written in the user config
 	// flushThrottle, sendRate, recvRate
@@ -34,6 +34,8 @@ const (
 	defaultSendRate            = int64(512000) // 500KB/s
 	defaultRecvRate            = int64(512000) // 500KB/s
 	defaultSendTimeout         = 10 * time.Second
+	defaultPingInterval        = 60 * time.Second
+	defaultPongTimeout         = 45 * time.Second
 )
 
 type receiveCbFunc func(chID byte, msgBytes []byte)
@@ -81,10 +83,15 @@ type MConnection struct {
 	errored     uint32
 	config      *MConnConfig
 
-	quit         chan struct{}
-	flushTimer   *cmn.ThrottleTimer // flush writes as necessary but throttled.
-	pingTimer    *cmn.RepeatTimer   // send pings periodically
-	chStatsTimer *cmn.RepeatTimer   // update channel stats periodically
+	quit       chan struct{}
+	flushTimer *cmn.ThrottleTimer // flush writes as necessary but throttled.
+	pingTimer  *cmn.RepeatTimer   // send pings periodically
+
+	// close conn if pong is not received in pongTimeout
+	pongTimer     *time.Timer
+	pongTimeoutCh chan bool // true - timeout, false - peer sent pong
+
+	chStatsTimer *cmn.RepeatTimer // update channel stats periodically
 
 	created time.Time // time of creation
 }
@@ -94,9 +101,17 @@ type MConnConfig struct {
 	SendRate int64 `mapstructure:"send_rate"`
 	RecvRate int64 `mapstructure:"recv_rate"`
 
-	MaxMsgPacketPayloadSize int
+	// Maximum payload size
+	MaxMsgPacketPayloadSize int `mapstructure:"max_msg_packet_payload_size"`
 
-	FlushThrottle time.Duration
+	// Interval to flush writes (throttled)
+	FlushThrottle time.Duration `mapstructure:"flush_throttle"`
+
+	// Interval to send pings
+	PingInterval time.Duration `mapstructure:"ping_interval"`
+
+	// Maximum wait time for pongs
+	PongTimeout time.Duration `mapstructure:"pong_timeout"`
 }
 
 func (cfg *MConnConfig) maxMsgPacketTotalSize() int {
@@ -110,6 +125,8 @@ func DefaultMConnConfig() *MConnConfig {
 		RecvRate:                defaultRecvRate,
 		MaxMsgPacketPayloadSize: defaultMaxMsgPacketPayloadSize,
 		FlushThrottle:           defaultFlushThrottle,
+		PingInterval:            defaultPingInterval,
+		PongTimeout:             defaultPongTimeout,
 	}
 }
 
@@ -125,6 +142,10 @@ func NewMConnection(conn net.Conn, chDescs []*ChannelDescriptor, onReceive recei
 
 // NewMConnectionWithConfig wraps net.Conn and creates multiplex connection with a config
 func NewMConnectionWithConfig(conn net.Conn, chDescs []*ChannelDescriptor, onReceive receiveCbFunc, onError errorCbFunc, config *MConnConfig) *MConnection {
+	if config.PongTimeout >= config.PingInterval {
+		panic("pongTimeout must be less than pingInterval (otherwise, next ping will reset pong timer)")
+	}
+
 	mconn := &MConnection{
 		conn:        conn,
 		bufReader:   bufio.NewReaderSize(conn, minReadBufferSize),
@@ -132,7 +153,7 @@ func NewMConnectionWithConfig(conn net.Conn, chDescs []*ChannelDescriptor, onRec
 		sendMonitor: flow.New(0, 0),
 		recvMonitor: flow.New(0, 0),
 		send:        make(chan struct{}, 1),
-		pong:        make(chan struct{}),
+		pong:        make(chan struct{}, 1),
 		onReceive:   onReceive,
 		onError:     onError,
 		config:      config,
@@ -169,7 +190,8 @@ func (c *MConnection) OnStart() error {
 	}
 	c.quit = make(chan struct{})
 	c.flushTimer = cmn.NewThrottleTimer("flush", c.config.FlushThrottle)
-	c.pingTimer = cmn.NewRepeatTimer("ping", pingTimeout)
+	c.pingTimer = cmn.NewRepeatTimer("ping", c.config.PingInterval)
+	c.pongTimeoutCh = make(chan bool, 1)
 	c.chStatsTimer = cmn.NewRepeatTimer("chStats", updateStats)
 	go c.sendRoutine()
 	go c.recvRoutine()
@@ -179,12 +201,12 @@ func (c *MConnection) OnStart() error {
 // OnStop implements BaseService
 func (c *MConnection) OnStop() {
 	c.BaseService.OnStop()
-	c.flushTimer.Stop()
-	c.pingTimer.Stop()
-	c.chStatsTimer.Stop()
 	if c.quit != nil {
 		close(c.quit)
 	}
+	c.flushTimer.Stop()
+	c.pingTimer.Stop()
+	c.chStatsTimer.Stop()
 	c.conn.Close() // nolint: errcheck
 
 	// We can't close pong safely here because
@@ -315,7 +337,18 @@ FOR_LOOP:
 			c.Logger.Debug("Send Ping")
 			wire.WriteByte(packetTypePing, c.bufWriter, &n, &err)
 			c.sendMonitor.Update(int(n))
+			c.Logger.Debug("Starting pong timer", "dur", c.config.PongTimeout)
+			c.pongTimer = time.AfterFunc(c.config.PongTimeout, func() {
+				c.pongTimeoutCh <- true
+			})
 			c.flush()
+		case timeout := <-c.pongTimeoutCh:
+			if timeout {
+				c.Logger.Debug("Pong timeout")
+				err = errors.New("pong timeout")
+			} else {
+				c.stopPongTimer()
+			}
 		case <-c.pong:
 			c.Logger.Debug("Send Pong")
 			wire.WriteByte(packetTypePong, c.bufWriter, &n, &err)
@@ -346,6 +379,7 @@ FOR_LOOP:
 	}
 
 	// Cleanup
+	c.stopPongTimer()
 }
 
 // Returns true if messages from channels were exhausted.
@@ -447,6 +481,7 @@ FOR_LOOP:
 		switch pktType {
 		case packetTypePing:
 			// TODO: prevent abuse, as they cause flush()'s.
+			// https://github.com/tendermint/tendermint/issues/1190
 			c.Logger.Debug("Receive Ping")
 			select {
 			case c.pong <- struct{}{}:
@@ -454,8 +489,12 @@ FOR_LOOP:
 				// never block
 			}
 		case packetTypePong:
-			// do nothing
 			c.Logger.Debug("Receive Pong")
+			select {
+			case c.pongTimeoutCh <- false:
+			default:
+				// never block
+			}
 		case packetTypeMsg:
 			pkt, n, err := msgPacket{}, int(0), error(nil)
 			wire.ReadBinaryPtr(&pkt, c.bufReader, c.config.maxMsgPacketTotalSize(), &n, &err)
@@ -503,6 +542,17 @@ FOR_LOOP:
 	}
 }
 
+// not goroutine-safe
+func (c *MConnection) stopPongTimer() {
+	if c.pongTimer != nil {
+		if !c.pongTimer.Stop() {
+			<-c.pongTimer.C
+		}
+		drain(c.pongTimeoutCh)
+		c.pongTimer = nil
+	}
+}
+
 type ConnectionStatus struct {
 	Duration    time.Duration
 	SendMonitor flow.Status
@@ -730,3 +780,13 @@ type msgPacket struct {
 func (p msgPacket) String() string {
 	return fmt.Sprintf("MsgPacket{%X:%X T:%X}", p.ChannelID, p.Bytes, p.EOF)
 }
+
+func drain(ch <-chan bool) {
+	for {
+		select {
+		case <-ch:
+		default:
+			return
+		}
+	}
+}

p2p/conn/connection_test.go

@@ -22,8 +22,11 @@ func createTestMConnection(conn net.Conn) *MConnection {
 }
 
 func createMConnectionWithCallbacks(conn net.Conn, onReceive func(chID byte, msgBytes []byte), onError func(r interface{})) *MConnection {
+	cfg := DefaultMConnConfig()
+	cfg.PingInterval = 90 * time.Millisecond
+	cfg.PongTimeout = 45 * time.Millisecond
 	chDescs := []*ChannelDescriptor{&ChannelDescriptor{ID: 0x01, Priority: 1, SendQueueCapacity: 1}}
-	c := NewMConnection(conn, chDescs, onReceive, onError)
+	c := NewMConnectionWithConfig(conn, chDescs, onReceive, onError, cfg)
 	c.SetLogger(log.TestingLogger())
 	return c
 }
@@ -116,6 +119,176 @@ func TestMConnectionStatus(t *testing.T) {
 	assert.Zero(status.Channels[0].SendQueueSize)
 }
 
+func TestMConnectionPongTimeoutResultsInError(t *testing.T) {
+	server, client := net.Pipe()
+	defer server.Close()
+	defer client.Close()
+
+	receivedCh := make(chan []byte)
+	errorsCh := make(chan interface{})
+	onReceive := func(chID byte, msgBytes []byte) {
+		receivedCh <- msgBytes
+	}
+	onError := func(r interface{}) {
+		errorsCh <- r
+	}
+	mconn := createMConnectionWithCallbacks(client, onReceive, onError)
+	err := mconn.Start()
+	require.Nil(t, err)
+	defer mconn.Stop()
+
+	serverGotPing := make(chan struct{})
+	go func() {
+		// read ping
+		server.Read(make([]byte, 1))
+		serverGotPing <- struct{}{}
+	}()
+	<-serverGotPing
+
+	pongTimerExpired := mconn.config.PongTimeout + 20*time.Millisecond
+	select {
+	case msgBytes := <-receivedCh:
+		t.Fatalf("Expected error, but got %v", msgBytes)
+	case err := <-errorsCh:
+		assert.NotNil(t, err)
+	case <-time.After(pongTimerExpired):
+		t.Fatalf("Expected to receive error after %v", pongTimerExpired)
+	}
+}
+
+func TestMConnectionMultiplePongsInTheBeginning(t *testing.T) {
+	server, client := net.Pipe()
+	defer server.Close()
+	defer client.Close()
+
+	receivedCh := make(chan []byte)
+	errorsCh := make(chan interface{})
+	onReceive := func(chID byte, msgBytes []byte) {
+		receivedCh <- msgBytes
+	}
+	onError := func(r interface{}) {
+		errorsCh <- r
+	}
+	mconn := createMConnectionWithCallbacks(client, onReceive, onError)
+	err := mconn.Start()
+	require.Nil(t, err)
+	defer mconn.Stop()
+
+	// sending 3 pongs in a row (abuse)
+	_, err = server.Write([]byte{packetTypePong})
+	require.Nil(t, err)
+	_, err = server.Write([]byte{packetTypePong})
+	require.Nil(t, err)
+	_, err = server.Write([]byte{packetTypePong})
+	require.Nil(t, err)
+
+	serverGotPing := make(chan struct{})
+	go func() {
+		// read ping (one byte)
+		_, err = server.Read(make([]byte, 1))
+		require.Nil(t, err)
+		serverGotPing <- struct{}{}
+		// respond with pong
+		_, err = server.Write([]byte{packetTypePong})
+		require.Nil(t, err)
+	}()
+	<-serverGotPing
+
+	pongTimerExpired := mconn.config.PongTimeout + 20*time.Millisecond
+	select {
+	case msgBytes := <-receivedCh:
+		t.Fatalf("Expected no data, but got %v", msgBytes)
+	case err := <-errorsCh:
+		t.Fatalf("Expected no error, but got %v", err)
+	case <-time.After(pongTimerExpired):
+		assert.True(t, mconn.IsRunning())
+	}
+}
+
+func TestMConnectionMultiplePings(t *testing.T) {
+	server, client := net.Pipe()
+	defer server.Close()
+	defer client.Close()
+
+	receivedCh := make(chan []byte)
+	errorsCh := make(chan interface{})
+	onReceive := func(chID byte, msgBytes []byte) {
+		receivedCh <- msgBytes
+	}
+	onError := func(r interface{}) {
+		errorsCh <- r
+	}
+	mconn := createMConnectionWithCallbacks(client, onReceive, onError)
+	err := mconn.Start()
+	require.Nil(t, err)
+	defer mconn.Stop()
+
+	// sending 3 pings in a row (abuse)
+	// see https://github.com/tendermint/tendermint/issues/1190
+	_, err = server.Write([]byte{packetTypePing})
+	require.Nil(t, err)
+	_, err = server.Read(make([]byte, 1))
+	require.Nil(t, err)
+	_, err = server.Write([]byte{packetTypePing})
+	require.Nil(t, err)
+	_, err = server.Read(make([]byte, 1))
+	require.Nil(t, err)
+	_, err = server.Write([]byte{packetTypePing})
+	require.Nil(t, err)
+	_, err = server.Read(make([]byte, 1))
+	require.Nil(t, err)
+
+	assert.True(t, mconn.IsRunning())
+}
+
+func TestMConnectionPingPongs(t *testing.T) {
+	server, client := net.Pipe()
+	defer server.Close()
+	defer client.Close()
+
+	receivedCh := make(chan []byte)
+	errorsCh := make(chan interface{})
+	onReceive := func(chID byte, msgBytes []byte) {
+		receivedCh <- msgBytes
+	}
+	onError := func(r interface{}) {
+		errorsCh <- r
+	}
+	mconn := createMConnectionWithCallbacks(client, onReceive, onError)
+	err := mconn.Start()
+	require.Nil(t, err)
+	defer mconn.Stop()
+
+	serverGotPing := make(chan struct{})
+	go func() {
+		// read ping
+		server.Read(make([]byte, 1))
+		serverGotPing <- struct{}{}
+		// respond with pong
+		_, err = server.Write([]byte{packetTypePong})
+		require.Nil(t, err)
+
+		time.Sleep(mconn.config.PingInterval)
+
+		// read ping
+		server.Read(make([]byte, 1))
+		// respond with pong
+		_, err = server.Write([]byte{packetTypePong})
+		require.Nil(t, err)
+	}()
+	<-serverGotPing
+
+	pongTimerExpired := (mconn.config.PongTimeout + 20*time.Millisecond) * 2
+	select {
+	case msgBytes := <-receivedCh:
+		t.Fatalf("Expected no data, but got %v", msgBytes)
+	case err := <-errorsCh:
+		t.Fatalf("Expected no error, but got %v", err)
+	case <-time.After(2 * pongTimerExpired):
+		assert.True(t, mconn.IsRunning())
+	}
+}
+
 func TestMConnectionStopsAndReturnsError(t *testing.T) {
 	assert, require := assert.New(t), require.New(t)
 
@@ -303,13 +476,7 @@ func TestMConnectionTrySend(t *testing.T) {
 		mconn.TrySend(0x01, msg)
 		resultCh <- "TrySend"
 	}()
-	go func() {
-		mconn.Send(0x01, msg)
-		resultCh <- "Send"
-	}()
 	assert.False(mconn.CanSend(0x01))
 	assert.False(mconn.TrySend(0x01, msg))
 	assert.Equal("TrySend", <-resultCh)
-	server.Read(make([]byte, len(msg)))
-	assert.Equal("Send", <-resultCh) // Order constrained by parallel blocking above
 }

p2p/conn/secret_connection_test.go

@@ -4,7 +4,7 @@ import (
 	"io"
 	"testing"
 
-	"github.com/tendermint/go-crypto"
+	crypto "github.com/tendermint/go-crypto"
 	cmn "github.com/tendermint/tmlibs/common"
 )
 

p2p/switch.go

@@ -5,6 +5,7 @@ import (
 	"math"
 	"math/rand"
 	"net"
+	"sync"
 	"time"
 
 	"github.com/pkg/errors"
@@ -200,9 +201,29 @@ func (sw *Switch) OnStop() {
 //---------------------------------------------------------------------
 // Peers
 
-// Peers returns the set of peers that are connected to the switch.
-func (sw *Switch) Peers() IPeerSet {
-	return sw.peers
+// Broadcast runs a go routine for each attempted send, which will block trying
+// to send for defaultSendTimeoutSeconds. Returns a channel which receives
+// success values for each attempted send (false if times out). Channel will be
+// closed once msg send to all peers.
+//
+// NOTE: Broadcast uses goroutines, so order of broadcast may not be preserved.
+func (sw *Switch) Broadcast(chID byte, msg interface{}) chan bool {
+	successChan := make(chan bool, len(sw.peers.List()))
+	sw.Logger.Debug("Broadcast", "channel", chID, "msg", msg)
+	var wg sync.WaitGroup
+	for _, peer := range sw.peers.List() {
+		wg.Add(1)
+		go func(peer Peer) {
+			defer wg.Done()
+			success := peer.Send(chID, msg)
+			successChan <- success
+		}(peer)
+	}
+	go func() {
+		wg.Wait()
+		close(successChan)
+	}()
+	return successChan
 }
 
 // NumPeers returns the count of outbound/inbound and outbound-dialing peers.
@@ -219,21 +240,9 @@ func (sw *Switch) NumPeers() (outbound, inbound, dialing int) {
 	return
 }
 
-// Broadcast runs a go routine for each attempted send, which will block
-// trying to send for defaultSendTimeoutSeconds. Returns a channel
-// which receives success values for each attempted send (false if times out).
-// NOTE: Broadcast uses goroutines, so order of broadcast may not be preserved.
-// TODO: Something more intelligent.
-func (sw *Switch) Broadcast(chID byte, msg interface{}) chan bool {
-	successChan := make(chan bool, len(sw.peers.List()))
-	sw.Logger.Debug("Broadcast", "channel", chID, "msg", msg)
-	for _, peer := range sw.peers.List() {
-		go func(peer Peer) {
-			success := peer.Send(chID, msg)
-			successChan <- success
-		}(peer)
-	}
-	return successChan
+// Peers returns the set of peers that are connected to the switch.
+func (sw *Switch) Peers() IPeerSet {
+	return sw.peers
 }
 
 // StopPeerForError disconnects from a peer due to external error.

p2p/switch_test.go

@@ -300,9 +300,7 @@ func TestSwitchFullConnectivity(t *testing.T) {
 	}
 }
 
-func BenchmarkSwitches(b *testing.B) {
-	b.StopTimer()
-
+func BenchmarkSwitchBroadcast(b *testing.B) {
 	s1, s2 := MakeSwitchPair(b, func(i int, sw *Switch) *Switch {
 		// Make bar reactors of bar channels each
 		sw.AddReactor("foo", NewTestReactor([]*conn.ChannelDescriptor{
@@ -320,7 +318,8 @@ func BenchmarkSwitches(b *testing.B) {
 
 	// Allow time for goroutines to boot up
 	time.Sleep(1 * time.Second)
-	b.StartTimer()
+
+	b.ResetTimer()
 
 	numSuccess, numFailure := 0, 0
 
@@ -338,7 +337,4 @@ func BenchmarkSwitches(b *testing.B) {
 	}
 
 	b.Logf("success: %v, failure: %v", numSuccess, numFailure)
-
-	// Allow everything to flush before stopping switches & closing connections.
-	b.StopTimer()
 }