reset streams on panic

p2p/protocol/autonatv2/client.go

@@ -253,6 +253,7 @@ func (ac *client) handleDialBack(s network.Stream) {
 	defer func() {
 		if rerr := recover(); rerr != nil {
 			fmt.Fprintf(os.Stderr, "caught panic: %s\n%s\n", rerr, debug.Stack())
+			s.Reset()
 		}
 	}()
 

p2p/protocol/autonatv2/server.go

@@ -21,6 +21,7 @@ import (
 	"math/rand"
 
 	ma "github.com/multiformats/go-multiaddr"
+	madns "github.com/multiformats/go-multiaddr-dns"
 	manet "github.com/multiformats/go-multiaddr/net"
 )
 
@@ -90,13 +91,6 @@ func (as *server) Close() {
 
 // handleDialRequest is the dial-request protocol stream handler
 func (as *server) handleDialRequest(s network.Stream) {
-	defer func() {
-		if rerr := recover(); rerr != nil {
-			fmt.Fprintf(os.Stderr, "caught panic: %s\n%s\n", rerr, debug.Stack())
-		}
-	}()
-
-	log.Debugf("received dial-request from: %s, addr: %s", s.Conn().RemotePeer(), s.Conn().RemoteMultiaddr())
 	evt := as.serveDialRequest(s)
 	log.Debugf("completed dial-request from %s, response status: %s, dial status: %s, err: %s",
 		s.Conn().RemotePeer(), evt.ResponseStatus, evt.DialStatus, evt.Error)
@@ -106,6 +100,15 @@ func (as *server) handleDialRequest(s network.Stream) {
 }
 
 func (as *server) serveDialRequest(s network.Stream) EventDialRequestCompleted {
+	// catching this panic is fine. In the worst case, we will stop serving autonatv2 requests by
+	// rate limitin
+	defer func() {
+		if rerr := recover(); rerr != nil {
+			fmt.Fprintf(os.Stderr, "caught panic: %s\n%s\n", rerr, debug.Stack())
+			s.Reset()
+		}
+	}()
+
 	if err := s.Scope().SetService(ServiceName); err != nil {
 		s.Reset()
 		log.Debugf("failed to attach stream to %s service: %w", ServiceName, err)
@@ -179,6 +182,11 @@ func (as *server) serveDialRequest(s network.Stream) EventDialRequestCompleted {
 		if !as.allowPrivateAddrs && !manet.IsPublicAddr(a) {
 			continue
 		}
+		// Don't dial any address with a dns component.
+		// We may leak some DNS configuration information by DNS resolution.
+		if madns.Matches(a) {
+			continue
+		}
 		if !as.dialerHost.Network().CanDial(p, a) {
 			continue
 		}