feat/606-enable-nat-traversal-via-hole-punching (#668)

* feat: base implementation of dcutr for hole-punching

* chore: removed circuit-relay imports from __init__

* feat: implemented dcutr protocol

* added test suite with mock setup

* Fix pre-commit hook issues in DCUtR implementation

* usages of CONNECT_TYPE and SYNC_TYPE have been replaced with HolePunch.Type.CONNECT and HolePunch.Type.SYNC

* added unit tests for dcutr and nat module and

* added multiaddr.get_peer_id() with proper DNS address handling and fixed method signature inconsistencies

* added assertions to verify DCUtR hole punch result in integration test

---------

Co-authored-by: Manu Sheel Gupta <[email protected]>

Author: Winter-Soren

Makefile

@@ -60,6 +60,7 @@ PB = libp2p/crypto/pb/crypto.proto \
 	libp2p/identity/identify/pb/identify.proto \
 	libp2p/host/autonat/pb/autonat.proto \
 	libp2p/relay/circuit_v2/pb/circuit.proto \
+	libp2p/relay/circuit_v2/pb/dcutr.proto \
 	libp2p/kad_dht/pb/kademlia.proto
 
 PY = $(PB:.proto=_pb2.py)

libp2p/abc.py

@@ -357,6 +357,14 @@ def get_streams(self) -> tuple[INetStream, ...]:
         :return: A tuple containing instances of INetStream.
         """
 
+    @abstractmethod
+    def get_transport_addresses(self) -> list[Multiaddr]:
+        """
+        Retrieve the transport addresses used by this connection.
+
+        :return: A list of multiaddresses used by the transport.
+        """
+
 
 # -------------------------- peermetadata interface.py --------------------------
 

libp2p/network/connection/swarm_connection.py

@@ -3,6 +3,7 @@
     TYPE_CHECKING,
 )
 
+from multiaddr import Multiaddr
 import trio
 
 from libp2p.abc import (
@@ -147,6 +148,24 @@ async def new_stream(self) -> NetStream:
     def get_streams(self) -> tuple[NetStream, ...]:
         return tuple(self.streams)
 
+    def get_transport_addresses(self) -> list[Multiaddr]:
+        """
+        Retrieve the transport addresses used by this connection.
+
+        Returns
+        -------
+        list[Multiaddr]
+            A list of multiaddresses used by the transport.
+
+        """
+        # Return the addresses from the peerstore for this peer
+        try:
+            peer_id = self.muxed_conn.peer_id
+            return self.swarm.peerstore.addrs(peer_id)
+        except Exception as e:
+            logging.warning(f"Error getting transport addresses: {e}")
+            return []
+
     def remove_stream(self, stream: NetStream) -> None:
         if stream not in self.streams:
             return

libp2p/relay/__init__.py

@@ -15,6 +15,10 @@
     RelayLimits,
     RelayResourceManager,
     Reservation,
+     DCUTR_PROTOCOL_ID,
+    DCUtRProtocol,
+    ReachabilityChecker,
+    is_private_ip,
 )
 
 __all__ = [
@@ -25,4 +29,9 @@
     "RelayLimits",
     "RelayResourceManager",
     "Reservation",
+    "DCUtRProtocol",
+    "DCUTR_PROTOCOL_ID",
+    "ReachabilityChecker",
+    "is_private_ip"
+
 ]

libp2p/relay/circuit_v2/__init__.py

@@ -5,6 +5,16 @@
 https://github.com/libp2p/specs/blob/master/relay/circuit-v2.md
 """
 
+from .dcutr import (
+    DCUtRProtocol,
+)
+from .dcutr import PROTOCOL_ID as DCUTR_PROTOCOL_ID
+
+from .nat import (
+    ReachabilityChecker,
+    is_private_ip,
+)
+
 from .discovery import (
     RelayDiscovery,
 )
@@ -29,4 +39,8 @@
     "RelayResourceManager",
     "CircuitV2Transport",
     "RelayDiscovery",
+     "DCUtRProtocol",
+    "DCUTR_PROTOCOL_ID",
+    "ReachabilityChecker",
+    "is_private_ip",
 ]