Don't expose Peer network through RemoteAddr

client.go

@@ -677,7 +677,7 @@ func (cl *Client) initiateProtocolHandshakes(
 	nc net.Conn,
 	t *Torrent,
 	outgoing, encryptHeader bool,
-	remoteAddr net.Addr,
+	remoteAddr PeerRemoteAddr,
 	network, connString string,
 ) (
 	c *PeerConn, err error,
@@ -699,7 +699,7 @@ func (cl *Client) initiateProtocolHandshakes(
 }
 
 // Returns nil connection and nil error if no connection could be established for valid reasons.
-func (cl *Client) establishOutgoingConnEx(t *Torrent, addr net.Addr, obfuscatedHeader bool) (*PeerConn, error) {
+func (cl *Client) establishOutgoingConnEx(t *Torrent, addr PeerRemoteAddr, obfuscatedHeader bool) (*PeerConn, error) {
 	dialCtx, cancel := context.WithTimeout(context.Background(), func() time.Duration {
 		cl.rLock()
 		defer cl.rUnlock()
@@ -723,7 +723,7 @@ func (cl *Client) establishOutgoingConnEx(t *Torrent, addr net.Addr, obfuscatedH
 
 // Returns nil connection and nil error if no connection could be established
 // for valid reasons.
-func (cl *Client) establishOutgoingConn(t *Torrent, addr net.Addr) (c *PeerConn, err error) {
+func (cl *Client) establishOutgoingConn(t *Torrent, addr PeerRemoteAddr) (c *PeerConn, err error) {
 	torrent.Add("establish outgoing connection", 1)
 	obfuscatedHeaderFirst := cl.config.HeaderObfuscationPolicy.Preferred
 	c, err = cl.establishOutgoingConnEx(t, addr, obfuscatedHeaderFirst)
@@ -748,7 +748,7 @@ func (cl *Client) establishOutgoingConn(t *Torrent, addr net.Addr) (c *PeerConn,
 
 // Called to dial out and run a connection. The addr we're given is already
 // considered half-open.
-func (cl *Client) outgoingConnection(t *Torrent, addr net.Addr, ps PeerSource, trusted bool) {
+func (cl *Client) outgoingConnection(t *Torrent, addr PeerRemoteAddr, ps PeerSource, trusted bool) {
 	cl.dialRateLimiter.Wait(context.Background())
 	c, err := cl.establishOutgoingConn(t, addr)
 	cl.lock()
@@ -967,7 +967,7 @@ func (cl *Client) sendInitialMessages(conn *PeerConn, torrent *Torrent) {
 					// that might be used to cache pending writes. Assuming 512KiB cached for
 					// sending, for 16KiB chunks.
 					Reqq:         1 << 5,
-					YourIp:       pp.CompactIp(addrIpOrNil(conn.RemoteAddr)),
+					YourIp:       pp.CompactIp(conn.remoteIp()),
 					Encryption:   cl.config.HeaderObfuscationPolicy.Preferred || !cl.config.HeaderObfuscationPolicy.RequirePreferred,
 					Port:         cl.incomingPeerPort(),
 					MetadataSize: torrent.metadataSize(),
@@ -1062,7 +1062,7 @@ func (cl *Client) gotMetadataExtensionMsg(payload []byte, t *Torrent, c *PeerCon
 	}
 }
 
-func (cl *Client) badPeerAddr(addr net.Addr) bool {
+func (cl *Client) badPeerAddr(addr PeerRemoteAddr) bool {
 	if ipa, ok := tryIpPortFromNetAddr(addr); ok {
 		return cl.badPeerIPPort(ipa.IP, ipa.Port)
 	}
@@ -1099,7 +1099,8 @@ func (cl *Client) newTorrent(ih metainfo.Hash, specStorage storage.ClientImpl) (
 		peers: prioritizedPeers{
 			om: btree.New(32),
 			getPrio: func(p PeerInfo) peerPriority {
-				return bep40PriorityIgnoreError(cl.publicAddr(addrIpOrNil(p.Addr)), p.addr())
+				ipPort := p.addr()
+				return bep40PriorityIgnoreError(cl.publicAddr(ipPort.IP), ipPort)
 			},
 		},
 		conns: make(map[*PeerConn]struct{}, 2*cl.config.EstablishedConnsPerTorrent),
@@ -1366,7 +1367,7 @@ func (cl *Client) banPeerIP(ip net.IP) {
 	cl.badPeerIPs[ip.String()] = struct{}{}
 }
 
-func (cl *Client) newConnection(nc net.Conn, outgoing bool, remoteAddr net.Addr, network, connString string) (c *PeerConn) {
+func (cl *Client) newConnection(nc net.Conn, outgoing bool, remoteAddr PeerRemoteAddr, network, connString string) (c *PeerConn) {
 	c = &PeerConn{
 		Peer: Peer{
 			outgoing:        outgoing,
@@ -1483,7 +1484,7 @@ func (cl *Client) ListenAddrs() (ret []net.Addr) {
 	return
 }
 
-func (cl *Client) onBadAccept(addr net.Addr) {
+func (cl *Client) onBadAccept(addr PeerRemoteAddr) {
 	ipa, ok := tryIpPortFromNetAddr(addr)
 	if !ok {
 		return

ipport.go

@@ -56,12 +56,15 @@ func (me ipPortAddr) String() string {
 	return net.JoinHostPort(me.IP.String(), strconv.FormatInt(int64(me.Port), 10))
 }
 
-func tryIpPortFromNetAddr(na net.Addr) (ret ipPortAddr, ok bool) {
-	ret.IP = addrIpOrNil(na)
-	if ret.IP == nil {
-		return
+func tryIpPortFromNetAddr(addr PeerRemoteAddr) (ipPortAddr, bool) {
+	ok := true
+	host, port, err := net.SplitHostPort(addr.String())
+	if err != nil {
+		ok = false
 	}
-	ret.Port = addrPortOrZero(na)
-	ok = true
-	return
+	portI64, err := strconv.ParseInt(port, 10, 0)
+	if err != nil {
+		ok = false
+	}
+	return ipPortAddr{net.ParseIP(host), int(portI64)}, ok
 }

peer_info.go

@@ -1,8 +1,6 @@
 package torrent
 
 import (
-	"net"
-
 	"github.com/anacrolix/dht/v2/krpc"
 
 	"github.com/anacrolix/torrent/peer_protocol"
@@ -11,7 +9,7 @@ import (
 // Peer connection info, handed about publicly.
 type PeerInfo struct {
 	Id     [20]byte
-	Addr   net.Addr
+	Addr   PeerRemoteAddr
 	Source PeerSource
 	// Peer is known to support encryption.
 	SupportsEncryption bool
@@ -41,5 +39,6 @@ func (me *PeerInfo) FromPex(na krpc.NodeAddr, fs peer_protocol.PexPeerFlags) {
 }
 
 func (me PeerInfo) addr() IpPort {
-	return IpPort{IP: addrIpOrNil(me.Addr), Port: uint16(addrPortOrZero(me.Addr))}
+	ipPort, _ := tryIpPortFromNetAddr(me.Addr)
+	return IpPort{ipPort.IP, uint16(ipPort.Port)}
 }

peerconn.go

@@ -42,6 +42,10 @@ type peerRequestState struct {
 	data []byte
 }
 
+type PeerRemoteAddr interface {
+	String() string
+}
+
 type Peer struct {
 	// First to ensure 64-bit alignment for atomics. See #262.
 	_stats ConnStats
@@ -52,7 +56,7 @@ type Peer struct {
 
 	outgoing   bool
 	network    string
-	RemoteAddr net.Addr
+	RemoteAddr PeerRemoteAddr
 	// True if the connection is operating over MSE obfuscation.
 	headerEncrypted bool
 	cryptoMethod    mse.CryptoMethod
@@ -169,7 +173,7 @@ func (cn *Peer) expectingChunks() bool {
 
 // Returns true if the connection is over IPv6.
 func (cn *PeerConn) ipv6() bool {
-	ip := addrIpOrNil(cn.RemoteAddr)
+	ip := cn.remoteIp()
 	if ip.To4() != nil {
 		return false
 	}
@@ -1626,7 +1630,8 @@ func (c *Peer) peerPriority() (peerPriority, error) {
 }
 
 func (c *Peer) remoteIp() net.IP {
-	return addrIpOrNil(c.RemoteAddr)
+	host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
+	return net.ParseIP(host)
 }
 
 func (c *Peer) remoteIpPort() IpPort {
@@ -1642,7 +1647,7 @@ func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
 	if c.outgoing {
 		f |= pp.PexOutgoingConn
 	}
-	if c.RemoteAddr != nil && strings.Contains(c.RemoteAddr.Network(), "udp") {
+	if c.utp() {
 		f |= pp.PexSupportsUtp
 	}
 	return f
@@ -1650,7 +1655,7 @@ func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
 
 // This returns the address to use if we want to dial the peer again. It incorporates the peer's
 // advertised listen port.
-func (c *PeerConn) dialAddr() net.Addr {
+func (c *PeerConn) dialAddr() PeerRemoteAddr {
 	if !c.outgoing && c.PeerListenPort != 0 {
 		switch addr := c.RemoteAddr.(type) {
 		case *net.TCPAddr:

peerconn_test.go

@@ -159,10 +159,10 @@ func TestConnPexPeerFlags(t *testing.T) {
 		{&PeerConn{Peer: Peer{outgoing: false, PeerPrefersEncryption: true}}, pp.PexPrefersEncryption},
 		{&PeerConn{Peer: Peer{outgoing: true, PeerPrefersEncryption: false}}, pp.PexOutgoingConn},
 		{&PeerConn{Peer: Peer{outgoing: true, PeerPrefersEncryption: true}}, pp.PexOutgoingConn | pp.PexPrefersEncryption},
-		{&PeerConn{Peer: Peer{RemoteAddr: udpAddr}}, pp.PexSupportsUtp},
-		{&PeerConn{Peer: Peer{RemoteAddr: udpAddr, outgoing: true}}, pp.PexOutgoingConn | pp.PexSupportsUtp},
-		{&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, outgoing: true}}, pp.PexOutgoingConn},
-		{&PeerConn{Peer: Peer{RemoteAddr: tcpAddr}}, 0},
+		{&PeerConn{Peer: Peer{RemoteAddr: udpAddr, network: udpAddr.Network()}}, pp.PexSupportsUtp},
+		{&PeerConn{Peer: Peer{RemoteAddr: udpAddr, network: udpAddr.Network(), outgoing: true}}, pp.PexOutgoingConn | pp.PexSupportsUtp},
+		{&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, network: tcpAddr.Network(), outgoing: true}}, pp.PexOutgoingConn},
+		{&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, network: tcpAddr.Network()}}, 0},
 	}
 	for i, tc := range testcases {
 		f := tc.conn.pexPeerFlags()
@@ -184,22 +184,22 @@ func TestConnPexEvent(t *testing.T) {
 	}{
 		{
 			pexAdd,
-			&PeerConn{Peer: Peer{RemoteAddr: udpAddr}},
+			&PeerConn{Peer: Peer{RemoteAddr: udpAddr, network: udpAddr.Network()}},
 			pexEvent{pexAdd, udpAddr, pp.PexSupportsUtp},
 		},
 		{
 			pexDrop,
-			&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, outgoing: true, PeerListenPort: dialTcpAddr.Port}},
+			&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, network: tcpAddr.Network(), outgoing: true, PeerListenPort: dialTcpAddr.Port}},
 			pexEvent{pexDrop, tcpAddr, pp.PexOutgoingConn},
 		},
 		{
 			pexAdd,
-			&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, PeerListenPort: dialTcpAddr.Port}},
+			&PeerConn{Peer: Peer{RemoteAddr: tcpAddr, network: tcpAddr.Network(), PeerListenPort: dialTcpAddr.Port}},
 			pexEvent{pexAdd, dialTcpAddr, 0},
 		},
 		{
 			pexDrop,
-			&PeerConn{Peer: Peer{RemoteAddr: udpAddr, PeerListenPort: dialUdpAddr.Port}},
+			&PeerConn{Peer: Peer{RemoteAddr: udpAddr, network: udpAddr.Network(), PeerListenPort: dialUdpAddr.Port}},
 			pexEvent{pexDrop, dialUdpAddr, pp.PexSupportsUtp},
 		},
 	}

pex.go

@@ -25,7 +25,7 @@ const (
 // represents a single connection (t=pexAdd) or disconnection (t=pexDrop) event
 type pexEvent struct {
 	t    pexEventType
-	addr net.Addr
+	addr PeerRemoteAddr
 	f    pp.PexPeerFlags
 }
 
@@ -45,7 +45,7 @@ func (me *pexMsgFactory) DeltaLen() int {
 type addrKey string
 
 // Returns the key to use to identify a given addr in the factory.
-func (me *pexMsgFactory) addrKey(addr net.Addr) addrKey {
+func (me *pexMsgFactory) addrKey(addr PeerRemoteAddr) addrKey {
 	return addrKey(addr.String())
 }
 
@@ -161,12 +161,10 @@ func (me *pexMsgFactory) PexMsg() pp.PexMsg {
 
 // Convert an arbitrary torrent peer Addr into one that can be represented by the compact addr
 // format.
-func nodeAddr(addr net.Addr) (_ krpc.NodeAddr, ok bool) {
-	ipport, ok := tryIpPortFromNetAddr(addr)
-	if !ok {
-		return
-	}
-	return krpc.NodeAddr{IP: shortestIP(ipport.IP), Port: ipport.Port}, true
+func nodeAddr(addr PeerRemoteAddr) (krpc.NodeAddr, bool) {
+	ipport, _ := tryIpPortFromNetAddr(addr)
+	ok := ipport.IP != nil
+	return krpc.NodeAddr{IP: shortestIP(ipport.IP), Port: ipport.Port}, ok
 }
 
 // mainly for the krpc marshallers