Add Resolver interface to transport

config/config.go

@@ -155,6 +155,9 @@ func (cfg *Config) makeSwarm() (*swarm.Swarm, error) {
 	if cfg.ResourceManager != nil {
 		opts = append(opts, swarm.WithResourceManager(cfg.ResourceManager))
 	}
+	if cfg.MultiaddrResolver != nil {
+		opts = append(opts, swarm.WithMultiaddrResolver(cfg.MultiaddrResolver))
+	}
 	// TODO: Make the swarm implementation configurable.
 	return swarm.NewSwarm(pid, cfg.Peerstore, opts...)
 }
@@ -229,7 +232,6 @@ func (cfg *Config) NewNode() (host.Host, error) {
 		EnablePing:          !cfg.DisablePing,
 		UserAgent:           cfg.UserAgent,
 		ProtocolVersion:     cfg.ProtocolVersion,
-		MultiaddrResolver:   cfg.MultiaddrResolver,
 		EnableHolePunching:  cfg.EnableHolePunching,
 		HolePunchingOptions: cfg.HolePunchingOptions,
 		EnableRelayService:  cfg.EnableRelayService,

core/transport/transport.go

@@ -77,6 +77,12 @@ type Transport interface {
 	Proxy() bool
 }
 
+// Resolver can be optionally implemented by transports that want to resolve or transform the
+// multiaddr.
+type Resolver interface {
+	Resolve(ctx context.Context, maddr ma.Multiaddr) ([]ma.Multiaddr, error)
+}
+
 // Listener is an interface closely resembling the net.Listener interface. The
 // only real difference is that Accept() returns Conn's of the type in this
 // package, and also exposes a Multiaddr method as opposed to a regular Addr

p2p/host/basic/basic_host.go

@@ -38,10 +38,6 @@ import (
 	msmux "github.com/multiformats/go-multistream"
 )
 
-// The maximum number of address resolution steps we'll perform for a single
-// peer (for all addresses).
-const maxAddressResolution = 32
-
 // addrChangeTickrInterval is the interval between two address change ticks.
 var addrChangeTickrInterval = 5 * time.Second
 
@@ -713,77 +709,9 @@ func (h *BasicHost) Connect(ctx context.Context, pi peer.AddrInfo) error {
 		}
 	}
 
-	resolved, err := h.resolveAddrs(ctx, h.Peerstore().PeerInfo(pi.ID))
-	if err != nil {
-		return err
-	}
-	h.Peerstore().AddAddrs(pi.ID, resolved, peerstore.TempAddrTTL)
-
 	return h.dialPeer(ctx, pi.ID)
 }
 
-func (h *BasicHost) resolveAddrs(ctx context.Context, pi peer.AddrInfo) ([]ma.Multiaddr, error) {
-	proto := ma.ProtocolWithCode(ma.P_P2P).Name
-	p2paddr, err := ma.NewMultiaddr("/" + proto + "/" + pi.ID.Pretty())
-	if err != nil {
-		return nil, err
-	}
-
-	resolveSteps := 0
-
-	// Recursively resolve all addrs.
-	//
-	// While the toResolve list is non-empty:
-	// * Pop an address off.
-	// * If the address is fully resolved, add it to the resolved list.
-	// * Otherwise, resolve it and add the results to the "to resolve" list.
-	toResolve := append(([]ma.Multiaddr)(nil), pi.Addrs...)
-	resolved := make([]ma.Multiaddr, 0, len(pi.Addrs))
-	for len(toResolve) > 0 {
-		// pop the last addr off.
-		addr := toResolve[len(toResolve)-1]
-		toResolve = toResolve[:len(toResolve)-1]
-
-		// if it's resolved, add it to the resolved list.
-		if !madns.Matches(addr) {
-			resolved = append(resolved, addr)
-			continue
-		}
-
-		resolveSteps++
-
-		// We've resolved too many addresses. We can keep all the fully
-		// resolved addresses but we'll need to skip the rest.
-		if resolveSteps >= maxAddressResolution {
-			log.Warnf(
-				"peer %s asked us to resolve too many addresses: %s/%s",
-				pi.ID,
-				resolveSteps,
-				maxAddressResolution,
-			)
-			continue
-		}
-
-		// otherwise, resolve it
-		reqaddr := addr.Encapsulate(p2paddr)
-		resaddrs, err := h.maResolver.Resolve(ctx, reqaddr)
-		if err != nil {
-			log.Infof("error resolving %s: %s", reqaddr, err)
-		}
-
-		// add the results to the toResolve list.
-		for _, res := range resaddrs {
-			pi, err := peer.AddrInfoFromP2pAddr(res)
-			if err != nil {
-				log.Infof("error parsing %s: %s", res, err)
-			}
-			toResolve = append(toResolve, pi.Addrs...)
-		}
-	}
-
-	return resolved, nil
-}
-
 // dialPeer opens a connection to peer, and makes sure to identify
 // the connection once it has been opened.
 func (h *BasicHost) dialPeer(ctx context.Context, p peer.ID) error {

p2p/host/basic/basic_host_test.go

@@ -17,14 +17,12 @@ import (
 	"github.com/libp2p/go-libp2p/core/peerstore"
 	"github.com/libp2p/go-libp2p/core/protocol"
 	"github.com/libp2p/go-libp2p/core/record"
-	"github.com/libp2p/go-libp2p/core/test"
 	"github.com/libp2p/go-libp2p/p2p/host/autonat"
 	"github.com/libp2p/go-libp2p/p2p/host/eventbus"
 	swarmt "github.com/libp2p/go-libp2p/p2p/net/swarm/testing"
 	"github.com/libp2p/go-libp2p/p2p/protocol/identify"
 
 	ma "github.com/multiformats/go-multiaddr"
-	madns "github.com/multiformats/go-multiaddr-dns"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -526,111 +524,6 @@ func TestProtoDowngrade(t *testing.T) {
 	assertWait(t, connectedOn, "/testing")
 }
 
-func TestAddrResolution(t *testing.T) {
-	ctx := context.Background()
-
-	p1 := test.RandPeerIDFatal(t)
-	p2 := test.RandPeerIDFatal(t)
-	addr1 := ma.StringCast("/dnsaddr/example.com")
-	addr2 := ma.StringCast("/ip4/192.0.2.1/tcp/123")
-	p2paddr1 := ma.StringCast("/dnsaddr/example.com/p2p/" + p1.Pretty())
-	p2paddr2 := ma.StringCast("/ip4/192.0.2.1/tcp/123/p2p/" + p1.Pretty())
-	p2paddr3 := ma.StringCast("/ip4/192.0.2.1/tcp/123/p2p/" + p2.Pretty())
-
-	backend := &madns.MockResolver{
-		TXT: map[string][]string{"_dnsaddr.example.com": {
-			"dnsaddr=" + p2paddr2.String(), "dnsaddr=" + p2paddr3.String(),
-		}},
-	}
-	resolver, err := madns.NewResolver(madns.WithDefaultResolver(backend))
-	require.NoError(t, err)
-
-	h, err := NewHost(swarmt.GenSwarm(t), &HostOpts{MultiaddrResolver: resolver})
-	require.NoError(t, err)
-	defer h.Close()
-
-	pi, err := peer.AddrInfoFromP2pAddr(p2paddr1)
-	require.NoError(t, err)
-
-	tctx, cancel := context.WithTimeout(ctx, time.Millisecond*100)
-	defer cancel()
-	_ = h.Connect(tctx, *pi)
-
-	addrs := h.Peerstore().Addrs(pi.ID)
-
-	require.Len(t, addrs, 2)
-	require.Contains(t, addrs, addr1)
-	require.Contains(t, addrs, addr2)
-}
-
-func TestAddrResolutionRecursive(t *testing.T) {
-	ctx := context.Background()
-
-	p1, err := test.RandPeerID()
-	if err != nil {
-		t.Error(err)
-	}
-	p2, err := test.RandPeerID()
-	if err != nil {
-		t.Error(err)
-	}
-	addr1 := ma.StringCast("/dnsaddr/example.com")
-	addr2 := ma.StringCast("/ip4/192.0.2.1/tcp/123")
-	p2paddr1 := ma.StringCast("/dnsaddr/example.com/p2p/" + p1.Pretty())
-	p2paddr2 := ma.StringCast("/dnsaddr/example.com/p2p/" + p2.Pretty())
-	p2paddr1i := ma.StringCast("/dnsaddr/foo.example.com/p2p/" + p1.Pretty())
-	p2paddr2i := ma.StringCast("/dnsaddr/bar.example.com/p2p/" + p2.Pretty())
-	p2paddr1f := ma.StringCast("/ip4/192.0.2.1/tcp/123/p2p/" + p1.Pretty())
-
-	backend := &madns.MockResolver{
-		TXT: map[string][]string{
-			"_dnsaddr.example.com": {
-				"dnsaddr=" + p2paddr1i.String(),
-				"dnsaddr=" + p2paddr2i.String(),
-			},
-			"_dnsaddr.foo.example.com": {
-				"dnsaddr=" + p2paddr1f.String(),
-			},
-			"_dnsaddr.bar.example.com": {
-				"dnsaddr=" + p2paddr2i.String(),
-			},
-		},
-	}
-	resolver, err := madns.NewResolver(madns.WithDefaultResolver(backend))
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	h, err := NewHost(swarmt.GenSwarm(t), &HostOpts{MultiaddrResolver: resolver})
-	require.NoError(t, err)
-	defer h.Close()
-
-	pi1, err := peer.AddrInfoFromP2pAddr(p2paddr1)
-	if err != nil {
-		t.Error(err)
-	}
-
-	tctx, cancel := context.WithTimeout(ctx, time.Millisecond*100)
-	defer cancel()
-	_ = h.Connect(tctx, *pi1)
-
-	addrs1 := h.Peerstore().Addrs(pi1.ID)
-	require.Len(t, addrs1, 2)
-	require.Contains(t, addrs1, addr1)
-	require.Contains(t, addrs1, addr2)
-
-	pi2, err := peer.AddrInfoFromP2pAddr(p2paddr2)
-	if err != nil {
-		t.Error(err)
-	}
-
-	_ = h.Connect(tctx, *pi2)
-
-	addrs2 := h.Peerstore().Addrs(pi2.ID)
-	require.Len(t, addrs2, 1)
-	require.Contains(t, addrs2, addr1)
-}
-
 func TestAddrChangeImmediatelyIfAddressNonEmpty(t *testing.T) {
 	ctx := context.Background()
 	taddrs := []ma.Multiaddr{ma.StringCast("/ip4/1.2.3.4/tcp/1234")}

p2p/net/swarm/dial_test.go

@@ -11,17 +11,18 @@ import (
 	"github.com/libp2p/go-libp2p/core/peer"
 	"github.com/libp2p/go-libp2p/core/peerstore"
 	testutil "github.com/libp2p/go-libp2p/core/test"
-	. "github.com/libp2p/go-libp2p/p2p/net/swarm"
+	"github.com/libp2p/go-libp2p/p2p/net/swarm"
 	swarmt "github.com/libp2p/go-libp2p/p2p/net/swarm/testing"
 
 	"github.com/libp2p/go-libp2p-testing/ci"
 
 	ma "github.com/multiformats/go-multiaddr"
+	madns "github.com/multiformats/go-multiaddr-dns"
 	manet "github.com/multiformats/go-multiaddr/net"
 	"github.com/stretchr/testify/require"
 )
 
-func closeSwarms(swarms []*Swarm) {
+func closeSwarms(swarms []*swarm.Swarm) {
 	for _, s := range swarms {
 		s.Close()
 	}
@@ -45,6 +46,44 @@ func TestBasicDialPeer(t *testing.T) {
 	s.Close()
 }
 
+func TestBasicDialPeerWithResolver(t *testing.T) {
+	t.Parallel()
+
+	mockResolver := madns.MockResolver{IP: make(map[string][]net.IPAddr)}
+	ipaddr, err := net.ResolveIPAddr("ip4", "127.0.0.1")
+	require.NoError(t, err)
+	mockResolver.IP["example.com"] = []net.IPAddr{*ipaddr}
+	resolver, err := madns.NewResolver(madns.WithDomainResolver("example.com", &mockResolver))
+	require.NoError(t, err)
+
+	swarms := makeSwarms(t, 2, swarmt.WithSwarmOpts([]swarm.Option{swarm.WithMultiaddrResolver(resolver)}))
+	defer closeSwarms(swarms)
+	s1 := swarms[0]
+	s2 := swarms[1]
+
+	// Change the multiaddr from /ip4/127.0.0.1/... to /dns4/example.com/... so
+	// that the resovler has to resolve this
+	var s2Addrs []ma.Multiaddr
+	for _, a := range s2.ListenAddresses() {
+		_, rest := ma.SplitFunc(a, func(c ma.Component) bool {
+			return c.Protocol().Code == ma.P_TCP || c.Protocol().Code == ma.P_UDP
+		},
+		)
+		if rest != nil {
+			s2Addrs = append(s2Addrs, ma.StringCast("/dns4/example.com").Encapsulate(rest))
+		}
+	}
+
+	s1.Peerstore().AddAddrs(s2.LocalPeer(), s2Addrs, peerstore.PermanentAddrTTL)
+
+	c, err := s1.DialPeer(context.Background(), s2.LocalPeer())
+	require.NoError(t, err)
+
+	s, err := c.NewStream(context.Background())
+	require.NoError(t, err)
+	s.Close()
+}
+
 func TestDialWithNoListeners(t *testing.T) {
 	t.Parallel()
 
@@ -90,7 +129,7 @@ func TestSimultDials(t *testing.T) {
 	{
 		var wg sync.WaitGroup
 		errs := make(chan error, 20) // 2 connect calls in each of the 10 for-loop iterations
-		connect := func(s *Swarm, dst peer.ID, addr ma.Multiaddr) {
+		connect := func(s *swarm.Swarm, dst peer.ID, addr ma.Multiaddr) {
 			// copy for other peer
 			log.Debugf("TestSimultOpen: connecting: %s --> %s (%s)", s.LocalPeer(), dst, addr)
 			s.Peerstore().AddAddr(dst, addr, peerstore.TempAddrTTL)
@@ -176,11 +215,11 @@ func TestDialWait(t *testing.T) {
 	}
 	duration := time.Since(before)
 
-	if duration < dialTimeout*DialAttempts {
-		t.Error("< dialTimeout * DialAttempts not being respected", duration, dialTimeout*DialAttempts)
+	if duration < dialTimeout*swarm.DialAttempts {
+		t.Error("< dialTimeout * DialAttempts not being respected", duration, dialTimeout*swarm.DialAttempts)
 	}
-	if duration > 2*dialTimeout*DialAttempts {
-		t.Error("> 2*dialTimeout * DialAttempts not being respected", duration, 2*dialTimeout*DialAttempts)
+	if duration > 2*dialTimeout*swarm.DialAttempts {
+		t.Error("> 2*dialTimeout * DialAttempts not being respected", duration, 2*dialTimeout*swarm.DialAttempts)
 	}
 
 	if !s1.Backoff().Backoff(s2p, s2addr) {
@@ -418,11 +457,11 @@ func TestDialBackoffClears(t *testing.T) {
 	require.Error(t, err, "dialing to broken addr worked...")
 	duration := time.Since(before)
 
-	if duration < dialTimeout*DialAttempts {
-		t.Error("< dialTimeout * DialAttempts not being respected", duration, dialTimeout*DialAttempts)
+	if duration < dialTimeout*swarm.DialAttempts {
+		t.Error("< dialTimeout * DialAttempts not being respected", duration, dialTimeout*swarm.DialAttempts)
 	}
-	if duration > 2*dialTimeout*DialAttempts {
-		t.Error("> 2*dialTimeout * DialAttempts not being respected", duration, 2*dialTimeout*DialAttempts)
+	if duration > 2*dialTimeout*swarm.DialAttempts {
+		t.Error("> 2*dialTimeout * DialAttempts not being respected", duration, 2*dialTimeout*swarm.DialAttempts)
 	}
 	require.True(t, s1.Backoff().Backoff(s2.LocalPeer(), s2bad), "s2 should now be on backoff")
 
@@ -462,7 +501,7 @@ func TestDialPeerFailed(t *testing.T) {
 	//   * [/ip4/127.0.0.1/tcp/34881] failed to negotiate security protocol: context deadline exceeded
 	// ...
 
-	dialErr, ok := err.(*DialError)
+	dialErr, ok := err.(*swarm.DialError)
 	if !ok {
 		t.Fatalf("expected *DialError, got %T", err)
 	}
@@ -617,5 +656,5 @@ func TestDialSelf(t *testing.T) {
 	s1 := swarms[0]
 
 	_, err := s1.DialPeer(context.Background(), s1.LocalPeer())
-	require.ErrorIs(t, err, ErrDialToSelf, "expected error from self dial")
+	require.ErrorIs(t, err, swarm.ErrDialToSelf, "expected error from self dial")
 }