Merge pull request #2248 from libp2p/simplify-nat

move NAT mapping logic out of the host, add tests for NAT handling

p2p/host/basic/basic_host.go

@@ -25,7 +25,6 @@ import (
 	"github.com/libp2p/go-libp2p/p2p/host/eventbus"
 	"github.com/libp2p/go-libp2p/p2p/host/pstoremanager"
 	"github.com/libp2p/go-libp2p/p2p/host/relaysvc"
-	inat "github.com/libp2p/go-libp2p/p2p/net/nat"
 	relayv2 "github.com/libp2p/go-libp2p/p2p/protocol/circuitv2/relay"
 	"github.com/libp2p/go-libp2p/p2p/protocol/holepunch"
 	"github.com/libp2p/go-libp2p/p2p/protocol/identify"
@@ -858,99 +857,19 @@ func (h *BasicHost) AllAddrs() []ma.Multiaddr {
 
 	finalAddrs = dedupAddrs(finalAddrs)
 
-	var natMappings []inat.Mapping
-
 	// natmgr is nil if we do not use nat option;
-	// h.natmgr.NAT() is nil if not ready, or no nat is available.
-	if h.natmgr != nil && h.natmgr.NAT() != nil {
-		natMappings = h.natmgr.NAT().Mappings()
-	}
-
-	if len(natMappings) > 0 {
+	if h.natmgr != nil {
 		// We have successfully mapped ports on our NAT. Use those
 		// instead of observed addresses (mostly).
 
-		// First, generate a mapping table.
-		// protocol -> internal port -> external addr
-		ports := make(map[string]map[int]net.Addr)
-		for _, m := range natMappings {
-			addr, err := m.ExternalAddr()
-			if err != nil {
-				// mapping not ready yet.
-				continue
-			}
-			protoPorts, ok := ports[m.Protocol()]
-			if !ok {
-				protoPorts = make(map[int]net.Addr)
-				ports[m.Protocol()] = protoPorts
-			}
-			protoPorts[m.InternalPort()] = addr
-		}
-
 		// Next, apply this mapping to our addresses.
 		for _, listen := range listenAddrs {
-			found := false
-			transport, rest := ma.SplitFunc(listen, func(c ma.Component) bool {
-				if found {
-					return true
-				}
-				switch c.Protocol().Code {
-				case ma.P_TCP, ma.P_UDP:
-					found = true
-				}
-				return false
-			})
-			if !manet.IsThinWaist(transport) {
-				continue
-			}
-
-			naddr, err := manet.ToNetAddr(transport)
-			if err != nil {
-				log.Error("error parsing net multiaddr %q: %s", transport, err)
+			extMaddr := h.natmgr.GetMapping(listen)
+			if extMaddr == nil {
+				// not mapped
 				continue
 			}
 
-			var (
-				ip       net.IP
-				iport    int
-				protocol string
-			)
-			switch naddr := naddr.(type) {
-			case *net.TCPAddr:
-				ip = naddr.IP
-				iport = naddr.Port
-				protocol = "tcp"
-			case *net.UDPAddr:
-				ip = naddr.IP
-				iport = naddr.Port
-				protocol = "udp"
-			default:
-				continue
-			}
-
-			if !ip.IsGlobalUnicast() && !ip.IsUnspecified() {
-				// We only map global unicast & unspecified addresses ports.
-				// Not broadcast, multicast, etc.
-				continue
-			}
-
-			mappedAddr, ok := ports[protocol][iport]
-			if !ok {
-				// Not mapped.
-				continue
-			}
-
-			mappedMaddr, err := manet.FromNetAddr(mappedAddr)
-			if err != nil {
-				log.Errorf("mapped addr can't be turned into a multiaddr %q: %s", mappedAddr, err)
-				continue
-			}
-
-			extMaddr := mappedMaddr
-			if rest != nil {
-				extMaddr = ma.Join(extMaddr, rest)
-			}
-
 			// if the router reported a sane address
 			if !manet.IsIPUnspecified(extMaddr) {
 				// Add in the mapped addr.

p2p/host/basic/mocks.go

@@ -0,0 +1,6 @@
+//go:build gomock || generate
+
+package basichost
+
+//go:generate sh -c "go run github.com/golang/mock/mockgen -build_flags=\"-tags=gomock\" -package basichost -destination mock_nat_test.go github.com/libp2p/go-libp2p/p2p/host/basic NAT"
+type NAT nat