Introduce option to skip duplicate ip check

In some scenarios like tests we want to disable the guard which prevents
peers connecting from the same ip.

Fixes #1632
Closes #1634

config/config.go

@@ -292,6 +292,9 @@ type P2PConfig struct {
 
 	// Comma separated list of peer IDs to keep private (will not be gossiped to other peers)
 	PrivatePeerIDs string `mapstructure:"private_peer_ids"`
+
+	// Toggle to disable guard against peers connecting from the same ip.
+	SkipDuplicatePeerIPCheck bool `mapstructure:"skip_duplicate_peer_ip_check"`
 }
 
 // DefaultP2PConfig returns a default configuration for the peer-to-peer layer
@@ -317,6 +320,7 @@ func TestP2PConfig() *P2PConfig {
 	cfg.ListenAddress = "tcp://0.0.0.0:36656"
 	cfg.SkipUPNP = true
 	cfg.FlushThrottleTimeout = 10
+	cfg.SkipDuplicatePeerIPCheck = true
 	return cfg
 }
 

p2p/peer_set.go

@@ -47,10 +47,6 @@ func (ps *PeerSet) Add(peer Peer) error {
 		return ErrSwitchDuplicatePeerID{peer.ID()}
 	}
 
-	if ps.hasIP(peer.RemoteIP()) {
-		return ErrSwitchDuplicatePeerIP{peer.RemoteIP()}
-	}
-
 	index := len(ps.list)
 	// Appending is safe even with other goroutines
 	// iterating over the ps.list slice.

p2p/peer_set_test.go

@@ -143,20 +143,6 @@ func TestPeerSetAddDuplicate(t *testing.T) {
 	assert.Equal(t, wantNilErrCount, gotNilErrCount, "invalid nil errCount")
 }
 
-func TestPeerSetAddDuplicateIP(t *testing.T) {
-	t.Parallel()
-
-	peerSet := NewPeerSet()
-
-	if err := peerSet.Add(randPeer(net.IP{172, 0, 0, 1})); err != nil {
-		t.Fatal(err)
-	}
-
-	// Add peer with same IP.
-	err := peerSet.Add(randPeer(net.IP{172, 0, 0, 1}))
-	assert.Equal(t, ErrSwitchDuplicatePeerIP{IP: net.IP{172, 0, 0, 1}}, err)
-}
-
 func TestPeerSetGet(t *testing.T) {
 	t.Parallel()
 

p2p/pex/pex_reactor_test.go

@@ -27,6 +27,7 @@ var (
 func init() {
 	config = cfg.DefaultP2PConfig()
 	config.PexReactor = true
+	config.SkipDuplicatePeerIPCheck = true
 }
 
 func TestPEXReactorBasic(t *testing.T) {
@@ -69,59 +70,59 @@ func TestPEXReactorAddRemovePeer(t *testing.T) {
 // peers have different IP addresses, they all have the same underlying remote
 // IP: 127.0.0.1.
 //
-// func TestPEXReactorRunning(t *testing.T) {
-// 	N := 3
-// 	switches := make([]*p2p.Switch, N)
-
-// 	// directory to store address books
-// 	dir, err := ioutil.TempDir("", "pex_reactor")
-// 	require.Nil(t, err)
-// 	defer os.RemoveAll(dir) // nolint: errcheck
-
-// 	books := make([]*addrBook, N)
-// 	logger := log.TestingLogger()
-
-// 	// create switches
-// 	for i := 0; i < N; i++ {
-// 		switches[i] = p2p.MakeSwitch(config, i, "testing", "123.123.123", func(i int, sw *p2p.Switch) *p2p.Switch {
-// 			books[i] = NewAddrBook(filepath.Join(dir, fmt.Sprintf("addrbook%d.json", i)), false)
-// 			books[i].SetLogger(logger.With("pex", i))
-// 			sw.SetAddrBook(books[i])
-
-// 			sw.SetLogger(logger.With("pex", i))
-
-// 			r := NewPEXReactor(books[i], &PEXReactorConfig{})
-// 			r.SetLogger(logger.With("pex", i))
-// 			r.SetEnsurePeersPeriod(250 * time.Millisecond)
-// 			sw.AddReactor("pex", r)
-
-// 			return sw
-// 		})
-// 	}
-
-// 	addOtherNodeAddrToAddrBook := func(switchIndex, otherSwitchIndex int) {
-// 		addr := switches[otherSwitchIndex].NodeInfo().NetAddress()
-// 		books[switchIndex].AddAddress(addr, addr)
-// 	}
-
-// 	addOtherNodeAddrToAddrBook(0, 1)
-// 	addOtherNodeAddrToAddrBook(1, 0)
-// 	addOtherNodeAddrToAddrBook(2, 1)
-
-// 	for i, sw := range switches {
-// 		sw.AddListener(p2p.NewDefaultListener("tcp", sw.NodeInfo().ListenAddr, true, logger.With("pex", i)))
-
-// 		err := sw.Start() // start switch and reactors
-// 		require.Nil(t, err)
-// 	}
-
-// 	assertPeersWithTimeout(t, switches, 10*time.Millisecond, 10*time.Second, N-1)
-
-// 	// stop them
-// 	for _, s := range switches {
-// 		s.Stop()
-// 	}
-// }
+func TestPEXReactorRunning(t *testing.T) {
+	N := 3
+	switches := make([]*p2p.Switch, N)
+
+	// directory to store address books
+	dir, err := ioutil.TempDir("", "pex_reactor")
+	require.Nil(t, err)
+	defer os.RemoveAll(dir) // nolint: errcheck
+
+	books := make([]*addrBook, N)
+	logger := log.TestingLogger()
+
+	// create switches
+	for i := 0; i < N; i++ {
+		switches[i] = p2p.MakeSwitch(config, i, "testing", "123.123.123", func(i int, sw *p2p.Switch) *p2p.Switch {
+			books[i] = NewAddrBook(filepath.Join(dir, fmt.Sprintf("addrbook%d.json", i)), false)
+			books[i].SetLogger(logger.With("pex", i))
+			sw.SetAddrBook(books[i])
+
+			sw.SetLogger(logger.With("pex", i))
+
+			r := NewPEXReactor(books[i], &PEXReactorConfig{})
+			r.SetLogger(logger.With("pex", i))
+			r.SetEnsurePeersPeriod(250 * time.Millisecond)
+			sw.AddReactor("pex", r)
+
+			return sw
+		})
+	}
+
+	addOtherNodeAddrToAddrBook := func(switchIndex, otherSwitchIndex int) {
+		addr := switches[otherSwitchIndex].NodeInfo().NetAddress()
+		books[switchIndex].AddAddress(addr, addr)
+	}
+
+	addOtherNodeAddrToAddrBook(0, 1)
+	addOtherNodeAddrToAddrBook(1, 0)
+	addOtherNodeAddrToAddrBook(2, 1)
+
+	for i, sw := range switches {
+		sw.AddListener(p2p.NewDefaultListener("tcp", sw.NodeInfo().ListenAddr, true, logger.With("pex", i)))
+
+		err := sw.Start() // start switch and reactors
+		require.Nil(t, err)
+	}
+
+	assertPeersWithTimeout(t, switches, 10*time.Millisecond, 10*time.Second, N-1)
+
+	// stop them
+	for _, s := range switches {
+		s.Stop()
+	}
+}
 
 func TestPEXReactorReceive(t *testing.T) {
 	r, book := createReactor(&PEXReactorConfig{})

p2p/switch.go

@@ -577,8 +577,9 @@ func (sw *Switch) addPeer(pc peerConn) error {
 	}
 
 	// Check for duplicate connection or peer info IP.
-	if sw.peers.HasIP(pc.RemoteIP()) ||
-		sw.peers.HasIP(peerNodeInfo.NetAddress().IP) {
+	if !sw.config.SkipDuplicatePeerIPCheck &&
+		(sw.peers.HasIP(pc.RemoteIP()) ||
+			sw.peers.HasIP(peerNodeInfo.NetAddress().IP)) {
 		return ErrSwitchDuplicatePeerIP{pc.RemoteIP()}
 	}
 

p2p/test_util.go

@@ -3,7 +3,6 @@ package p2p
 import (
 	"fmt"
 	"net"
-	"sync/atomic"
 
 	crypto "github.com/tendermint/go-crypto"
 	cmn "github.com/tendermint/tmlibs/common"
@@ -132,8 +131,6 @@ func StartSwitches(switches []*Switch) error {
 	return nil
 }
 
-var listenAddrSuffix uint32 = 1
-
 func MakeSwitch(cfg *cfg.P2PConfig, i int, network, version string, initSwitch func(int, *Switch) *Switch) *Switch {
 	// new switch, add reactors
 	// TODO: let the config be passed in?
@@ -148,7 +145,7 @@ func MakeSwitch(cfg *cfg.P2PConfig, i int, network, version string, initSwitch f
 		Moniker:    cmn.Fmt("switch%d", i),
 		Network:    network,
 		Version:    version,
-		ListenAddr: fmt.Sprintf("127.0.0.%d:%d", atomic.AddUint32(&listenAddrSuffix, 1), cmn.RandIntn(64512)+1023),
+		ListenAddr: fmt.Sprintf("127.0.0.1:%d", cmn.RandIntn(64512)+1023),
 	}
 	for ch := range sw.reactorsByCh {
 		ni.Channels = append(ni.Channels, ch)