Locate target peer using dial addr when receiving a holepunch rendezvous

[btrtrc.git] / torrent.go

diff --git a/torrent.go b/torrent.go
index eef9c0cb8da16ca8a5924e5918633a57e69953c0..c7ca2549230cfd5e2ae6bc9cd0b0bec9f0997213 100644 (file)
--- a/torrent.go
+++ b/torrent.go
@@ -2002,8 +2002,9 @@ func (t *Torrent) addPeerConn(c *PeerConn) (err error) {
        }
        t.conns[c] = struct{}{}
        t.cl.event.Broadcast()
+       // We'll never receive the "p" extended handshake parameter.
        if !t.cl.config.DisablePEX && !c.PeerExtensionBytes.SupportsExtended() {
-               t.pex.Add(c) // as no further extended handshake expected
+               t.pex.Add(c)
        }
        return nil
 }
@@ -2678,10 +2679,13 @@ func (t *Torrent) checkValidReceiveChunk(r Request) error {
        return nil
 }
 
-func (t *Torrent) peerConnsWithRemoteAddrPort(addrPort netip.AddrPort) (ret []*PeerConn) {
+func (t *Torrent) peerConnsWithDialAddrPort(target netip.AddrPort) (ret []*PeerConn) {
        for pc := range t.conns {
-               addr := pc.remoteAddrPort()
-               if !(addr.Ok && addr.Value == addrPort) {
+               dialAddr, err := pc.remoteDialAddrPort()
+               if err != nil {
+                       continue
+               }
+               if dialAddr != target {
                        continue
                }
                ret = append(ret, pc)
@@ -2725,7 +2729,18 @@ func (t *Torrent) handleReceivedUtHolepunchMsg(msg utHolepunch.Msg, sender *Peer
        case utHolepunch.Rendezvous:
                t.logger.Printf("got holepunch rendezvous request for %v from %p", msg.AddrPort, sender)
                sendMsg := sendUtHolepunchMsg
-               targets := t.peerConnsWithRemoteAddrPort(msg.AddrPort)
+               senderAddrPort, err := sender.remoteDialAddrPort()
+               if err != nil {
+                       sender.logger.Levelf(
+                               log.Warning,
+                               "error getting ut_holepunch rendezvous sender's dial address: %v",
+                               err,
+                       )
+                       // There's no better error code. The sender's address itself is invalid. I don't see
+                       // this error message being appropriate anywhere else anyway.
+                       sendMsg(sender, utHolepunch.Error, msg.AddrPort, utHolepunch.NoSuchPeer)
+               }
+               targets := t.peerConnsWithDialAddrPort(msg.AddrPort)
                if len(targets) == 0 {
                        sendMsg(sender, utHolepunch.Error, msg.AddrPort, utHolepunch.NotConnected)
                        return nil
@@ -2736,7 +2751,7 @@ func (t *Torrent) handleReceivedUtHolepunchMsg(msg utHolepunch.Msg, sender *Peer
                                continue
                        }
                        sendMsg(sender, utHolepunch.Connect, msg.AddrPort, 0)
-                       sendMsg(pc, utHolepunch.Connect, sender.remoteAddrPort().Unwrap(), 0)
+                       sendMsg(pc, utHolepunch.Connect, senderAddrPort, 0)
                }
                return nil
        case utHolepunch.Connect: