Merge pull request #846 from sumanjeet0012/bugfix/kbucket_split_fix

Fix: kbucket splitting in routing table.

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)
@@ -68,6 +69,8 @@ PYI = $(PB:.proto=_pb2.pyi)
 ## Set default to `protobufs`, otherwise `format` is called when typing only `make`
 all: protobufs
 
+.PHONY: protobufs clean-proto
+
 protobufs: $(PY)
 
 %_pb2.py: %.proto
@@ -76,6 +79,11 @@ protobufs: $(PY)
 clean-proto:
 	rm -f $(PY) $(PYI)
 
+# Force protobuf regeneration by making them always out of date
+$(PY): FORCE
+
+FORCE:
+
 # docs commands
 
 docs: check-docs

README.md

@@ -12,13 +12,13 @@
 [![Build Status](https://img.shields.io/github/actions/workflow/status/libp2p/py-libp2p/tox.yml?branch=main&label=build%20status)](https://github.com/libp2p/py-libp2p/actions/workflows/tox.yml)
 [![Docs build](https://readthedocs.org/projects/py-libp2p/badge/?version=latest)](http://py-libp2p.readthedocs.io/en/latest/?badge=latest)
 
-> ⚠️ **Warning:** py-libp2p is an experimental and work-in-progress repo under development. We do not yet recommend using py-libp2p in production environments.
+> py-libp2p has moved beyond its experimental roots and is steadily progressing toward production readiness. The core features are stable, and we’re focused on refining performance, expanding protocol support, and ensuring smooth interop with other libp2p implementations. We welcome contributions and real-world usage feedback to help us reach full production maturity.
 
 Read more in the [documentation on ReadTheDocs](https://py-libp2p.readthedocs.io/). [View the release notes](https://py-libp2p.readthedocs.io/en/latest/release_notes.html).
 
 ## Maintainers
 
-Currently maintained by [@pacrob](https://github.com/pacrob), [@seetadev](https://github.com/seetadev) and [@dhuseby](https://github.com/dhuseby), looking for assistance!
+Currently maintained by [@pacrob](https://github.com/pacrob), [@seetadev](https://github.com/seetadev) and [@dhuseby](https://github.com/dhuseby). Please reach out to us for collaboration or active feedback. If you have questions, feel free to open a new [discussion](https://github.com/libp2p/py-libp2p/discussions). We are also available on the libp2p Discord — join us at #py-libp2p [sub-channel](https://discord.gg/d92MEugb).
 
 ## Feature Breakdown
 
@@ -34,19 +34,19 @@ ______________________________________________________________________
 | -------------------------------------- | :--------: | :---------------------------------------------------------------------------------: |
 | **`libp2p-tcp`**                       |     ✅     | [source](https://github.com/libp2p/py-libp2p/blob/main/libp2p/transport/tcp/tcp.py) |
 | **`libp2p-quic`**                      |     🌱     |                                                                                     |
-| **`libp2p-websocket`**                 |     ❌     |                                                                                     |
-| **`libp2p-webrtc-browser-to-server`**  |     ❌     |                                                                                     |
-| **`libp2p-webrtc-private-to-private`** |     ❌     |                                                                                     |
+| **`libp2p-websocket`**                 |     🌱     |                                                                                     |
+| **`libp2p-webrtc-browser-to-server`**  |     🌱     |                                                                                     |
+| **`libp2p-webrtc-private-to-private`** |     🌱     |                                                                                     |
 
 ______________________________________________________________________
 
 ### NAT Traversal
 
-| **NAT Traversal**             | **Status** |
-| ----------------------------- | :--------: |
-| **`libp2p-circuit-relay-v2`** |     ❌     |
-| **`libp2p-autonat`**          |     ❌     |
-| **`libp2p-hole-punching`**    |     ❌     |
+| **NAT Traversal**             | **Status** |                                   **Source**                                    |
+| ----------------------------- | :--------: | :-----------------------------------------------------------------------------: |
+| **`libp2p-circuit-relay-v2`** |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/relay/circuit_v2) |
+| **`libp2p-autonat`**          |     ✅     |   [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/host/autonat)   |
+| **`libp2p-hole-punching`**    |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/relay/circuit_v2) |
 
 ______________________________________________________________________
 
@@ -54,27 +54,27 @@ ______________________________________________________________________
 
 | **Secure Communication** | **Status** |                                  **Source**                                   |
 | ------------------------ | :--------: | :---------------------------------------------------------------------------: |
-| **`libp2p-noise`**       |     🌱     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/security/noise) |
-| **`libp2p-tls`**         |     ❌     |                                                                               |
+| **`libp2p-noise`**       |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/security/noise) |
+| **`libp2p-tls`**         |     🌱     |                                                                               |
 
 ______________________________________________________________________
 
 ### Discovery
 
-| **Discovery**        | **Status** |
-| -------------------- | :--------: |
-| **`bootstrap`**      |     ❌     |
-| **`random-walk`**    |     ❌     |
-| **`mdns-discovery`** |     ❌     |
-| **`rendezvous`**     |     ❌     |
+| **Discovery**        | **Status** |                                     **Source**                                     |
+| -------------------- | :--------: | :--------------------------------------------------------------------------------: |
+| **`bootstrap`**      |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/discovery/bootstrap) |
+| **`random-walk`**    |     🌱     |                                                                                    |
+| **`mdns-discovery`** |     ✅     |   [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/discovery/mdns)    |
+| **`rendezvous`**     |     🌱     |                                                                                    |
 
 ______________________________________________________________________
 
 ### Peer Routing
 
-| **Peer Routing**     | **Status** |
-| -------------------- | :--------: |
-| **`libp2p-kad-dht`** |     ❌     |
+| **Peer Routing**     | **Status** |                               **Source**                               |
+| -------------------- | :--------: | :--------------------------------------------------------------------: |
+| **`libp2p-kad-dht`** |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/kad_dht) |
 
 ______________________________________________________________________
 
@@ -89,10 +89,10 @@ ______________________________________________________________________
 
 ### Stream Muxers
 
-| **Stream Muxers**  | **Status** |                                         **Status**                                         |
-| ------------------ | :--------: | :----------------------------------------------------------------------------------------: |
-| **`libp2p-yamux`** |     🌱     |                                                                                            |
-| **`libp2p-mplex`** |     🛠️     | [source](https://github.com/libp2p/py-libp2p/blob/main/libp2p/stream_muxer/mplex/mplex.py) |
+| **Stream Muxers**  | **Status** |                                    **Source**                                     |
+| ------------------ | :--------: | :-------------------------------------------------------------------------------: |
+| **`libp2p-yamux`** |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/stream_muxer/yamux) |
+| **`libp2p-mplex`** |     ✅     | [source](https://github.com/libp2p/py-libp2p/tree/main/libp2p/stream_muxer/mplex) |
 
 ______________________________________________________________________
 
@@ -100,7 +100,7 @@ ______________________________________________________________________
 
 | **Storage**         | **Status** |
 | ------------------- | :--------: |
-| **`libp2p-record`** |     ❌     |
+| **`libp2p-record`** |     🌱     |
 
 ______________________________________________________________________
 

docs/examples.mDNS.rst

@@ -0,0 +1,64 @@
+mDNS Peer Discovery Example
+===========================
+
+This example demonstrates how to use mDNS (Multicast DNS) for peer discovery in py-libp2p.
+
+Prerequisites
+-------------
+
+First, ensure you have py-libp2p installed and your environment is activated:
+
+.. code-block:: console
+
+    $ python -m pip install libp2p
+
+Running the Example
+-------------------
+
+The mDNS demo script allows you to discover peers on your local network using mDNS. To start a peer, run:
+
+.. code-block:: console
+
+    $ mdns-demo
+
+You should see output similar to:
+
+.. code-block:: console
+
+    Run this from another console to start another peer on a different port:
+
+    python mdns-demo -p <ANOTHER_PORT>
+
+    Waiting for mDNS peer discovery events...
+
+    2025-06-20 23:28:12,052 - libp2p.example.discovery.mdns - INFO - Starting peer Discovery
+
+To discover peers, open another terminal and run the same command with a different port:
+
+.. code-block:: console
+
+    $ python mdns-demo -p 9001
+
+You should see output indicating that a new peer has been discovered:
+
+.. code-block:: console
+
+    Run this from the same folder in another console to start another peer on a different port:
+
+    python mdns-demo -p <ANOTHER_PORT>
+
+    Waiting for mDNS peer discovery events...
+
+    2025-06-20 23:43:43,786 - libp2p.example.discovery.mdns - INFO - Starting peer Discovery
+    2025-06-20 23:43:43,790 - libp2p.example.discovery.mdns - INFO - Discovered: 16Uiu2HAmGxy5NdQEjZWtrYUMrzdp3Syvg7MB2E5Lx8weA9DanYxj
+
+When a new peer is discovered, its peer ID will be printed in the console output.
+
+How it Works
+------------
+
+- Each node advertises itself on the local network using mDNS.
+- When a new peer is discovered, the handler prints its peer ID.
+- This is useful for local peer discovery without requiring a DHT or bootstrap nodes.
+
+You can modify the script to perform additional actions when peers are discovered, such as opening streams or exchanging messages.

docs/examples.rst

@@ -13,3 +13,4 @@ Examples
    examples.pubsub
    examples.circuit_relay
    examples.kademlia
+   examples.mDNS

docs/libp2p.discovery.bootstrap.rst

@@ -0,0 +1,13 @@
+libp2p.discovery.bootstrap package
+==================================
+
+Submodules
+----------
+
+Module contents
+---------------
+
+.. automodule:: libp2p.discovery.bootstrap
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/libp2p.discovery.events.rst

@@ -0,0 +1,21 @@
+libp2p.discovery.events package
+===============================
+
+Submodules
+----------
+
+libp2p.discovery.events.peerDiscovery module
+--------------------------------------------
+
+.. automodule:: libp2p.discovery.events.peerDiscovery
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: libp2p.discovery.events
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/libp2p.discovery.mdns.rst

@@ -0,0 +1,45 @@
+libp2p.discovery.mdns package
+=============================
+
+Submodules
+----------
+
+libp2p.discovery.mdns.broadcaster module
+----------------------------------------
+
+.. automodule:: libp2p.discovery.mdns.broadcaster
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+libp2p.discovery.mdns.listener module
+-------------------------------------
+
+.. automodule:: libp2p.discovery.mdns.listener
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+libp2p.discovery.mdns.mdns module
+---------------------------------
+
+.. automodule:: libp2p.discovery.mdns.mdns
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+libp2p.discovery.mdns.utils module
+----------------------------------
+
+.. automodule:: libp2p.discovery.mdns.utils
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: libp2p.discovery.mdns
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/libp2p.discovery.rst

@@ -0,0 +1,23 @@
+libp2p.discovery package
+========================
+
+Subpackages
+-----------
+
+.. toctree::
+   :maxdepth: 4
+
+   libp2p.discovery.bootstrap
+   libp2p.discovery.events
+   libp2p.discovery.mdns
+
+Submodules
+----------
+
+Module contents
+---------------
+
+.. automodule:: libp2p.discovery
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/libp2p.rst

@@ -8,6 +8,7 @@ Subpackages
    :maxdepth: 4
 
    libp2p.crypto
+   libp2p.discovery
    libp2p.host
    libp2p.identity
    libp2p.io

docs/release_notes.rst

@@ -3,6 +3,65 @@ Release Notes
 
 .. towncrier release notes start
 
+py-libp2p v0.2.9 (2025-07-09)
+-----------------------------
+
+Breaking Changes
+~~~~~~~~~~~~~~~~
+
+- Reordered the arguments to ``upgrade_security`` to place ``is_initiator`` before ``peer_id``, and made ``peer_id`` optional.
+  This allows the method to reflect the fact that peer identity is not required for inbound connections. (`#681 <https://github.com/libp2p/py-libp2p/issues/681>`__)
+
+
+Bugfixes
+~~~~~~~~
+
+- Add timeout wrappers in:
+  1. ``multiselect.py``: ``negotiate`` function
+  2. ``multiselect_client.py``: ``select_one_of`` , ``query_multistream_command`` functions
+  to prevent indefinite hangs when a remote peer does not respond. (`#696 <https://github.com/libp2p/py-libp2p/issues/696>`__)
+- Align stream creation logic with yamux specification (`#701 <https://github.com/libp2p/py-libp2p/issues/701>`__)
+- Fixed an issue in ``Pubsub`` where async validators were not handled reliably under concurrency. Now uses a safe aggregator list for consistent behavior. (`#702 <https://github.com/libp2p/py-libp2p/issues/702>`__)
+
+
+Features
+~~~~~~~~
+
+- Added support for ``Kademlia DHT`` in py-libp2p. (`#579 <https://github.com/libp2p/py-libp2p/issues/579>`__)
+- Limit concurrency in ``push_identify_to_peers`` to prevent resource congestion under high peer counts. (`#621 <https://github.com/libp2p/py-libp2p/issues/621>`__)
+- Store public key and peer ID in peerstore during handshake
+
+  Modified the InsecureTransport class to accept an optional peerstore parameter and updated the handshake process to store the received public key and peer ID in the peerstore when available.
+
+  Added test cases to verify:
+  1. The peerstore remains unchanged when handshake fails due to peer ID mismatch
+  2. The handshake correctly adds a public key to a peer ID that already exists in the peerstore but doesn't have a public key yet (`#631 <https://github.com/libp2p/py-libp2p/issues/631>`__)
+- Fixed several flow-control and concurrency issues in the ``YamuxStream`` class. Previously, stress-testing revealed that transferring data over ``DEFAULT_WINDOW_SIZE`` would break the stream due to inconsistent window update handling and lock management. The fixes include:
+
+  - Removed sending of window updates during writes to maintain correct flow-control.
+  - Added proper timeout handling when releasing and acquiring locks to prevent concurrency errors.
+  - Corrected the ``read`` function to properly handle window updates for both ``read_until_EOF`` and ``read_n_bytes``.
+  - Added event logging at ``send_window_updates`` and ``waiting_for_window_updates`` for better observability. (`#639 <https://github.com/libp2p/py-libp2p/issues/639>`__)
+- Added support for ``Multicast DNS`` in py-libp2p (`#649 <https://github.com/libp2p/py-libp2p/issues/649>`__)
+- Optimized pubsub publishing to send multiple topics in a single message instead of separate messages per topic. (`#685 <https://github.com/libp2p/py-libp2p/issues/685>`__)
+- Optimized pubsub message writing by implementing a write_msg() method that uses pre-allocated buffers and single write operations, improving performance by eliminating separate varint prefix encoding and write operations in FloodSub and GossipSub. (`#687 <https://github.com/libp2p/py-libp2p/issues/687>`__)
+- Added peer exchange and backoff logic as part of Gossipsub v1.1 upgrade (`#690 <https://github.com/libp2p/py-libp2p/issues/690>`__)
+
+
+Internal Changes - for py-libp2p Contributors
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+- Added sparse connect utility function to pubsub test utilities for creating test networks with configurable connectivity. (`#679 <https://github.com/libp2p/py-libp2p/issues/679>`__)
+- Added comprehensive tests for pubsub connection utility functions to verify degree limits are enforced, excess peers are handled correctly, and edge cases (degree=0, negative values, empty lists) are managed gracefully. (`#707 <https://github.com/libp2p/py-libp2p/issues/707>`__)
+- Added extra tests for identify push concurrency cap under high peer load (`#708 <https://github.com/libp2p/py-libp2p/issues/708>`__)
+
+
+Miscellaneous Changes
+~~~~~~~~~~~~~~~~~~~~~
+
+- `#678 <https://github.com/libp2p/py-libp2p/issues/678>`__, `#684 <https://github.com/libp2p/py-libp2p/issues/684>`__
+
+
 py-libp2p v0.2.8 (2025-06-10)
 -----------------------------
 

examples/bootstrap/bootstrap.py

@@ -0,0 +1,136 @@
+import argparse
+import logging
+import secrets
+
+import multiaddr
+import trio
+
+from libp2p import new_host
+from libp2p.abc import PeerInfo
+from libp2p.crypto.secp256k1 import create_new_key_pair
+from libp2p.discovery.events.peerDiscovery import peerDiscovery
+
+# Configure logging
+logger = logging.getLogger("libp2p.discovery.bootstrap")
+logger.setLevel(logging.INFO)
+handler = logging.StreamHandler()
+handler.setFormatter(
+    logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+)
+logger.addHandler(handler)
+
+# Configure root logger to only show warnings and above to reduce noise
+# This prevents verbose DEBUG messages from multiaddr, DNS, etc.
+logging.getLogger().setLevel(logging.WARNING)
+
+# Specifically silence noisy libraries
+logging.getLogger("multiaddr").setLevel(logging.WARNING)
+logging.getLogger("root").setLevel(logging.WARNING)
+
+
+def on_peer_discovery(peer_info: PeerInfo) -> None:
+    """Handler for peer discovery events."""
+    logger.info(f"🔍 Discovered peer: {peer_info.peer_id}")
+    logger.debug(f"   Addresses: {[str(addr) for addr in peer_info.addrs]}")
+
+
+# Example bootstrap peers
+BOOTSTRAP_PEERS = [
+    "/dnsaddr/github.com/p2p/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN",
+    "/dnsaddr/cloudflare.com/p2p/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN",
+    "/dnsaddr/google.com/p2p/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN",
+    "/dnsaddr/bootstrap.libp2p.io/p2p/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN",
+    "/dnsaddr/bootstrap.libp2p.io/p2p/QmbLHAnMoJPWSCR5Zhtx6BHJX9KiKNN6tpvbUcqanj75Nb",
+    "/ip4/104.131.131.82/tcp/4001/p2p/QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ",
+    "/ip6/2604:a880:1:20::203:d001/tcp/4001/p2p/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM",
+    "/ip4/128.199.219.111/tcp/4001/p2p/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64",
+    "/ip4/104.236.76.40/tcp/4001/p2p/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64",
+    "/ip4/178.62.158.247/tcp/4001/p2p/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd",
+    "/ip6/2604:a880:1:20::203:d001/tcp/4001/p2p/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM",
+    "/ip6/2400:6180:0:d0::151:6001/tcp/4001/p2p/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu",
+    "/ip6/2a03:b0c0:0:1010::23:1001/tcp/4001/p2p/QmSoLueR4xBeUbY9WZ9xGUUxunbKWcrNFTDAadQJmocnWm",
+]
+
+
+async def run(port: int, bootstrap_addrs: list[str]) -> None:
+    """Run the bootstrap discovery example."""
+    # Generate key pair
+    secret = secrets.token_bytes(32)
+    key_pair = create_new_key_pair(secret)
+
+    # Create listen address
+    listen_addr = multiaddr.Multiaddr(f"/ip4/0.0.0.0/tcp/{port}")
+
+    # Register peer discovery handler
+    peerDiscovery.register_peer_discovered_handler(on_peer_discovery)
+
+    logger.info("🚀 Starting Bootstrap Discovery Example")
+    logger.info(f"📍 Listening on: {listen_addr}")
+    logger.info(f"🌐 Bootstrap peers: {len(bootstrap_addrs)}")
+
+    print("\n" + "=" * 60)
+    print("Bootstrap Discovery Example")
+    print("=" * 60)
+    print("This example demonstrates connecting to bootstrap peers.")
+    print("Watch the logs for peer discovery events!")
+    print("Press Ctrl+C to exit.")
+    print("=" * 60)
+
+    # Create and run host with bootstrap discovery
+    host = new_host(key_pair=key_pair, bootstrap=bootstrap_addrs)
+
+    try:
+        async with host.run(listen_addrs=[listen_addr]):
+            # Keep running and log peer discovery events
+            await trio.sleep_forever()
+    except KeyboardInterrupt:
+        logger.info("👋 Shutting down...")
+
+
+def main() -> None:
+    """Main entry point."""
+    description = """
+    Bootstrap Discovery Example for py-libp2p
+
+    This example demonstrates how to use bootstrap peers for peer discovery.
+    Bootstrap peers are predefined peers that help new nodes join the network.
+
+    Usage:
+        python bootstrap.py -p 8000
+        python bootstrap.py -p 8001 --custom-bootstrap \\
+            "/ip4/127.0.0.1/tcp/8000/p2p/QmYourPeerID"
+    """
+
+    parser = argparse.ArgumentParser(
+        description=description, formatter_class=argparse.RawDescriptionHelpFormatter
+    )
+    parser.add_argument(
+        "-p", "--port", default=0, type=int, help="Port to listen on (default: random)"
+    )
+    parser.add_argument(
+        "--custom-bootstrap",
+        nargs="*",
+        help="Custom bootstrap addresses (space-separated)",
+    )
+    parser.add_argument(
+        "-v", "--verbose", action="store_true", help="Enable verbose output"
+    )
+
+    args = parser.parse_args()
+
+    if args.verbose:
+        logger.setLevel(logging.DEBUG)
+
+    # Use custom bootstrap addresses if provided, otherwise use defaults
+    bootstrap_addrs = (
+        args.custom_bootstrap if args.custom_bootstrap else BOOTSTRAP_PEERS
+    )
+
+    try:
+        trio.run(run, args.port, bootstrap_addrs)
+    except KeyboardInterrupt:
+        logger.info("Exiting...")
+
+
+if __name__ == "__main__":
+    main()

examples/chat/chat.py

@@ -43,6 +43,9 @@ async def run(port: int, destination: str) -> None:
     listen_addr = multiaddr.Multiaddr(f"/ip4/0.0.0.0/tcp/{port}")
     host = new_host()
     async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
+        # Start the peer-store cleanup task
+        nursery.start_soon(host.get_peerstore().start_cleanup_task, 60)
+
         if not destination:  # its the server
 
             async def stream_handler(stream: INetStream) -> None:

examples/echo/echo.py

@@ -45,7 +45,10 @@ async def run(port: int, destination: str, seed: int | None = None) -> None:
         secret = secrets.token_bytes(32)
 
     host = new_host(key_pair=create_new_key_pair(secret))
-    async with host.run(listen_addrs=[listen_addr]):
+    async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
+        # Start the peer-store cleanup task
+        nursery.start_soon(host.get_peerstore().start_cleanup_task, 60)
+
         print(f"I am {host.get_id().to_string()}")
 
         if not destination:  # its the server

examples/identify/identify.py

@@ -1,6 +1,7 @@
 import argparse
 import base64
 import logging
+import sys
 
 import multiaddr
 import trio
@@ -8,10 +9,13 @@ import trio
 from libp2p import (
     new_host,
 )
-from libp2p.identity.identify.identify import ID as IDENTIFY_PROTOCOL_ID
-from libp2p.identity.identify.pb.identify_pb2 import (
-    Identify,
+from libp2p.identity.identify.identify import (
+    ID as IDENTIFY_PROTOCOL_ID,
+    identify_handler_for,
+    parse_identify_response,
 )
+from libp2p.identity.identify.pb.identify_pb2 import Identify
+from libp2p.peer.envelope import debug_dump_envelope, unmarshal_envelope
 from libp2p.peer.peerinfo import (
     info_from_p2p_addr,
 )
@@ -30,10 +34,11 @@ def decode_multiaddrs(raw_addrs):
     return decoded_addrs
 
 
-def print_identify_response(identify_response):
+def print_identify_response(identify_response: Identify):
     """Pretty-print Identify response."""
     public_key_b64 = base64.b64encode(identify_response.public_key).decode("utf-8")
     listen_addrs = decode_multiaddrs(identify_response.listen_addrs)
+    signed_peer_record = unmarshal_envelope(identify_response.signedPeerRecord)
     try:
         observed_addr_decoded = decode_multiaddrs([identify_response.observed_addr])
     except Exception:
@@ -49,8 +54,10 @@ def print_identify_response(identify_response):
         f"  Agent Version: {identify_response.agent_version}"
     )
 
+    debug_dump_envelope(signed_peer_record)
 
-async def run(port: int, destination: str) -> None:
+
+async def run(port: int, destination: str, use_varint_format: bool = True) -> None:
     localhost_ip = "0.0.0.0"
 
     if not destination:
@@ -58,39 +65,159 @@ async def run(port: int, destination: str) -> None:
         listen_addr = multiaddr.Multiaddr(f"/ip4/{localhost_ip}/tcp/{port}")
         host_a = new_host()
 
-        async with host_a.run(listen_addrs=[listen_addr]):
+        # Set up identify handler with specified format
+        # Set use_varint_format = False, if want to checkout the Signed-PeerRecord
+        identify_handler = identify_handler_for(
+            host_a, use_varint_format=use_varint_format
+        )
+        host_a.set_stream_handler(IDENTIFY_PROTOCOL_ID, identify_handler)
+
+        async with (
+            host_a.run(listen_addrs=[listen_addr]),
+            trio.open_nursery() as nursery,
+        ):
+            # Start the peer-store cleanup task
+            nursery.start_soon(host_a.get_peerstore().start_cleanup_task, 60)
+
+            # Get the actual address and replace 0.0.0.0 with 127.0.0.1 for client
+            # connections
+            server_addr = str(host_a.get_addrs()[0])
+            client_addr = server_addr.replace("/ip4/0.0.0.0/", "/ip4/127.0.0.1/")
+
+            format_name = "length-prefixed" if use_varint_format else "raw protobuf"
+            format_flag = "--raw-format" if not use_varint_format else ""
             print(
-                "First host listening. Run this from another console:\n\n"
-                f"identify-demo "
-                f"-d {host_a.get_addrs()[0]}\n"
+                f"First host listening (using {format_name} format). "
+                f"Run this from another console:\n\n"
+                f"identify-demo {format_flag} -d {client_addr}\n"
             )
             print("Waiting for incoming identify request...")
-            await trio.sleep_forever()
+
+            # Add a custom handler to show connection events
+            async def custom_identify_handler(stream):
+                peer_id = stream.muxed_conn.peer_id
+                print(f"\n🔗 Received identify request from peer: {peer_id}")
+
+                # Show remote address in multiaddr format
+                try:
+                    from libp2p.identity.identify.identify import (
+                        _remote_address_to_multiaddr,
+                    )
+
+                    remote_address = stream.get_remote_address()
+                    if remote_address:
+                        observed_multiaddr = _remote_address_to_multiaddr(
+                            remote_address
+                        )
+                        # Add the peer ID to create a complete multiaddr
+                        complete_multiaddr = f"{observed_multiaddr}/p2p/{peer_id}"
+                        print(f"   Remote address: {complete_multiaddr}")
+                    else:
+                        print(f"   Remote address: {remote_address}")
+                except Exception:
+                    print(f"   Remote address: {stream.get_remote_address()}")
+
+                # Call the original handler
+                await identify_handler(stream)
+
+                print(f"✅ Successfully processed identify request from {peer_id}")
+
+            # Replace the handler with our custom one
+            host_a.set_stream_handler(IDENTIFY_PROTOCOL_ID, custom_identify_handler)
+
+            try:
+                await trio.sleep_forever()
+            except KeyboardInterrupt:
+                print("\n🛑 Shutting down listener...")
+                logger.info("Listener interrupted by user")
+                return
 
     else:
         # Create second host (dialer)
         listen_addr = multiaddr.Multiaddr(f"/ip4/{localhost_ip}/tcp/{port}")
         host_b = new_host()
 
-        async with host_b.run(listen_addrs=[listen_addr]):
+        async with (
+            host_b.run(listen_addrs=[listen_addr]),
+            trio.open_nursery() as nursery,
+        ):
+            # Start the peer-store cleanup task
+            nursery.start_soon(host_b.get_peerstore().start_cleanup_task, 60)
+
             # Connect to the first host
             print(f"dialer (host_b) listening on {host_b.get_addrs()[0]}")
             maddr = multiaddr.Multiaddr(destination)
             info = info_from_p2p_addr(maddr)
             print(f"Second host connecting to peer: {info.peer_id}")
 
-            await host_b.connect(info)
+            try:
+                await host_b.connect(info)
+            except Exception as e:
+                error_msg = str(e)
+                if "unable to connect" in error_msg or "SwarmException" in error_msg:
+                    print(f"\n❌ Cannot connect to peer: {info.peer_id}")
+                    print(f"   Address: {destination}")
+                    print(f"   Error: {error_msg}")
+                    print(
+                        "\n💡 Make sure the peer is running and the address is correct."
+                    )
+                    return
+                else:
+                    # Re-raise other exceptions
+                    raise
+
             stream = await host_b.new_stream(info.peer_id, (IDENTIFY_PROTOCOL_ID,))
 
             try:
                 print("Starting identify protocol...")
-                response = await stream.read()
+
+                # Read the response using the utility function
+                from libp2p.utils.varint import read_length_prefixed_protobuf
+
+                response = await read_length_prefixed_protobuf(
+                    stream, use_varint_format
+                )
+                full_response = response
+
                 await stream.close()
-                identify_msg = Identify()
-                identify_msg.ParseFromString(response)
+
+                # Parse the response using the robust protocol-level function
+                # This handles both old and new formats automatically
+                identify_msg = parse_identify_response(full_response)
                 print_identify_response(identify_msg)
+
             except Exception as e:
-                print(f"Identify protocol error: {e}")
+                error_msg = str(e)
+                print(f"Identify protocol error: {error_msg}")
+
+                # Check for specific format mismatch errors
+                if "Error parsing message" in error_msg or "DecodeError" in error_msg:
+                    print("\n" + "=" * 60)
+                    print("FORMAT MISMATCH DETECTED!")
+                    print("=" * 60)
+                    if use_varint_format:
+                        print(
+                            "You are using length-prefixed format (default) but the "
+                            "listener"
+                        )
+                        print("is using raw protobuf format.")
+                        print(
+                            "\nTo fix this, run the dialer with the --raw-format flag:"
+                        )
+                        print(f"identify-demo --raw-format -d {destination}")
+                    else:
+                        print("You are using raw protobuf format but the listener")
+                        print("is using length-prefixed format (default).")
+                        print(
+                            "\nTo fix this, run the dialer without the --raw-format "
+                            "flag:"
+                        )
+                        print(f"identify-demo -d {destination}")
+                    print("=" * 60)
+                else:
+                    import traceback
+
+                    traceback.print_exc()
 
             return
 
@@ -98,9 +225,12 @@ async def run(port: int, destination: str) -> None:
 def main() -> None:
     description = """
     This program demonstrates the libp2p identify protocol.
-    First run identify-demo -p <PORT>' to start a listener.
+    First run 'identify-demo -p <PORT> [--raw-format]' to start a listener.
     Then run 'identify-demo <ANOTHER_PORT> -d <DESTINATION>'
     where <DESTINATION> is the multiaddress shown by the listener.
+
+    Use --raw-format to send raw protobuf messages (old format) instead of
+    length-prefixed protobuf messages (new format, default).
     """
 
     example_maddr = (
@@ -115,12 +245,35 @@ def main() -> None:
         type=str,
         help=f"destination multiaddr string, e.g. {example_maddr}",
     )
+    parser.add_argument(
+        "--raw-format",
+        action="store_true",
+        help=(
+            "use raw protobuf format (old format) instead of "
+            "length-prefixed (new format)"
+        ),
+    )
+
     args = parser.parse_args()
 
+    # Determine format: use varint (length-prefixed) if --raw-format is specified,
+    # otherwise use raw protobuf format (old format)
+    use_varint_format = args.raw_format
+
     try:
-        trio.run(run, *(args.port, args.destination))
+        if args.destination:
+            # Run in dialer mode
+            trio.run(run, *(args.port, args.destination, use_varint_format))
+        else:
+            # Run in listener mode
+            trio.run(run, *(args.port, args.destination, use_varint_format))
     except KeyboardInterrupt:
-        pass
+        print("\n👋 Goodbye!")
+        logger.info("Application interrupted by user")
+    except Exception as e:
+        print(f"\n❌ Error: {str(e)}")
+        logger.error("Error: %s", str(e))
+        sys.exit(1)
 
 
 if __name__ == "__main__":

examples/identify_push/identify_push_demo.py

@@ -11,23 +11,26 @@ This example shows how to:
 
 import logging
 
+import multiaddr
 import trio
 
 from libp2p import (
     new_host,
 )
+from libp2p.abc import (
+    INetStream,
+)
 from libp2p.crypto.secp256k1 import (
     create_new_key_pair,
 )
 from libp2p.custom_types import (
     TProtocol,
 )
-from libp2p.identity.identify import (
-    identify_handler_for,
+from libp2p.identity.identify.pb.identify_pb2 import (
+    Identify,
 )
 from libp2p.identity.identify_push import (
     ID_PUSH,
-    identify_push_handler_for,
     push_identify_to_peer,
 )
 from libp2p.peer.peerinfo import (
@@ -38,8 +41,145 @@ from libp2p.peer.peerinfo import (
 logger = logging.getLogger(__name__)
 
 
+def create_custom_identify_handler(host, host_name: str):
+    """Create a custom identify handler that displays received information."""
+
+    async def handle_identify(stream: INetStream) -> None:
+        peer_id = stream.muxed_conn.peer_id
+        print(f"\n🔍 {host_name} received identify request from peer: {peer_id}")
+
+        # Get the standard identify response using the existing function
+        from libp2p.identity.identify.identify import (
+            _mk_identify_protobuf,
+            _remote_address_to_multiaddr,
+        )
+
+        # Get observed address
+        observed_multiaddr = None
+        try:
+            remote_address = stream.get_remote_address()
+            if remote_address:
+                observed_multiaddr = _remote_address_to_multiaddr(remote_address)
+        except Exception:
+            pass
+
+        # Build the identify protobuf
+        identify_msg = _mk_identify_protobuf(host, observed_multiaddr)
+        response_data = identify_msg.SerializeToString()
+
+        print(f"   📋 {host_name} identify information:")
+        if identify_msg.HasField("protocol_version"):
+            print(f"      Protocol Version: {identify_msg.protocol_version}")
+        if identify_msg.HasField("agent_version"):
+            print(f"      Agent Version: {identify_msg.agent_version}")
+        if identify_msg.HasField("public_key"):
+            print(f"      Public Key: {identify_msg.public_key.hex()[:16]}...")
+        if identify_msg.listen_addrs:
+            print("      Listen Addresses:")
+            for addr_bytes in identify_msg.listen_addrs:
+                addr = multiaddr.Multiaddr(addr_bytes)
+                print(f"        - {addr}")
+        if identify_msg.protocols:
+            print("      Supported Protocols:")
+            for protocol in identify_msg.protocols:
+                print(f"        - {protocol}")
+
+        # Send the response
+        await stream.write(response_data)
+        await stream.close()
+
+    return handle_identify
+
+
+def create_custom_identify_push_handler(host, host_name: str):
+    """Create a custom identify/push handler that displays received information."""
+
+    async def handle_identify_push(stream: INetStream) -> None:
+        peer_id = stream.muxed_conn.peer_id
+        print(f"\n📤 {host_name} received identify/push from peer: {peer_id}")
+
+        try:
+            # Read the identify message using the utility function
+            from libp2p.utils.varint import read_length_prefixed_protobuf
+
+            data = await read_length_prefixed_protobuf(stream, use_varint_format=True)
+
+            # Parse the identify message
+            identify_msg = Identify()
+            identify_msg.ParseFromString(data)
+
+            print("   📋 Received identify information:")
+            if identify_msg.HasField("protocol_version"):
+                print(f"      Protocol Version: {identify_msg.protocol_version}")
+            if identify_msg.HasField("agent_version"):
+                print(f"      Agent Version: {identify_msg.agent_version}")
+            if identify_msg.HasField("public_key"):
+                print(f"      Public Key: {identify_msg.public_key.hex()[:16]}...")
+            if identify_msg.HasField("observed_addr") and identify_msg.observed_addr:
+                observed_addr = multiaddr.Multiaddr(identify_msg.observed_addr)
+                print(f"      Observed Address: {observed_addr}")
+            if identify_msg.listen_addrs:
+                print("      Listen Addresses:")
+                for addr_bytes in identify_msg.listen_addrs:
+                    addr = multiaddr.Multiaddr(addr_bytes)
+                    print(f"        - {addr}")
+            if identify_msg.protocols:
+                print("      Supported Protocols:")
+                for protocol in identify_msg.protocols:
+                    print(f"        - {protocol}")
+
+            # Update the peerstore with the new information
+            from libp2p.identity.identify_push.identify_push import (
+                _update_peerstore_from_identify,
+            )
+
+            await _update_peerstore_from_identify(
+                host.get_peerstore(), peer_id, identify_msg
+            )
+
+            print(f"   ✅ {host_name} updated peerstore with new information")
+
+        except Exception as e:
+            print(f"   ❌ Error processing identify/push: {e}")
+        finally:
+            await stream.close()
+
+    return handle_identify_push
+
+
+async def display_peerstore_info(host, host_name: str, peer_id, description: str):
+    """Display peerstore information for a specific peer."""
+    peerstore = host.get_peerstore()
+
+    try:
+        addrs = peerstore.addrs(peer_id)
+    except Exception:
+        addrs = []
+
+    try:
+        protocols = peerstore.get_protocols(peer_id)
+    except Exception:
+        protocols = []
+
+    print(f"\n📚 {host_name} peerstore for {description}:")
+    print(f"   Peer ID: {peer_id}")
+    if addrs:
+        print("   Addresses:")
+        for addr in addrs:
+            print(f"     - {addr}")
+    else:
+        print("   Addresses: None")
+
+    if protocols:
+        print("   Protocols:")
+        for protocol in protocols:
+            print(f"     - {protocol}")
+    else:
+        print("   Protocols: None")
+
+
 async def main() -> None:
-    print("\n==== Starting Identify-Push Example ====\n")
+    print("\n==== Starting Enhanced Identify-Push Example ====\n")
 
     # Create key pairs for the two hosts
     key_pair_1 = create_new_key_pair()
@@ -48,45 +188,57 @@ async def main() -> None:
     # Create the first host
     host_1 = new_host(key_pair=key_pair_1)
 
-    # Set up the identify and identify/push handlers
-    host_1.set_stream_handler(TProtocol("/ipfs/id/1.0.0"), identify_handler_for(host_1))
-    host_1.set_stream_handler(ID_PUSH, identify_push_handler_for(host_1))
+    # Set up custom identify and identify/push handlers
+    host_1.set_stream_handler(
+        TProtocol("/ipfs/id/1.0.0"), create_custom_identify_handler(host_1, "Host 1")
+    )
+    host_1.set_stream_handler(
+        ID_PUSH, create_custom_identify_push_handler(host_1, "Host 1")
+    )
 
     # Create the second host
     host_2 = new_host(key_pair=key_pair_2)
 
-    # Set up the identify and identify/push handlers
-    host_2.set_stream_handler(TProtocol("/ipfs/id/1.0.0"), identify_handler_for(host_2))
-    host_2.set_stream_handler(ID_PUSH, identify_push_handler_for(host_2))
+    # Set up custom identify and identify/push handlers
+    host_2.set_stream_handler(
+        TProtocol("/ipfs/id/1.0.0"), create_custom_identify_handler(host_2, "Host 2")
+    )
+    host_2.set_stream_handler(
+        ID_PUSH, create_custom_identify_push_handler(host_2, "Host 2")
+    )
 
     # Start listening on random ports using the run context manager
-    import multiaddr
-
     listen_addr_1 = multiaddr.Multiaddr("/ip4/127.0.0.1/tcp/0")
     listen_addr_2 = multiaddr.Multiaddr("/ip4/127.0.0.1/tcp/0")
 
-    async with host_1.run([listen_addr_1]), host_2.run([listen_addr_2]):
+    async with (
+        host_1.run([listen_addr_1]),
+        host_2.run([listen_addr_2]),
+        trio.open_nursery() as nursery,
+    ):
+        # Start the peer-store cleanup task
+        nursery.start_soon(host_1.get_peerstore().start_cleanup_task, 60)
+        nursery.start_soon(host_2.get_peerstore().start_cleanup_task, 60)
+
         # Get the addresses of both hosts
         addr_1 = host_1.get_addrs()[0]
-        logger.info(f"Host 1 listening on {addr_1}")
-        print(f"Host 1 listening on {addr_1}")
-        print(f"Peer ID: {host_1.get_id().pretty()}")
-
         addr_2 = host_2.get_addrs()[0]
-        logger.info(f"Host 2 listening on {addr_2}")
-        print(f"Host 2 listening on {addr_2}")
-        print(f"Peer ID: {host_2.get_id().pretty()}")
 
-        print("\nConnecting Host 2 to Host 1...")
+        print("🏠 Host Configuration:")
+        print(f"   Host 1: {addr_1}")
+        print(f"   Host 1 Peer ID: {host_1.get_id().pretty()}")
+        print(f"   Host 2: {addr_2}")
+        print(f"   Host 2 Peer ID: {host_2.get_id().pretty()}")
+
+        print("\n🔗 Connecting Host 2 to Host 1...")
 
         # Connect host_2 to host_1
         peer_info = info_from_p2p_addr(addr_1)
         await host_2.connect(peer_info)
-        logger.info("Host 2 connected to Host 1")
-        print("Host 2 successfully connected to Host 1")
+        print("✅ Host 2 successfully connected to Host 1")
 
         # Run the identify protocol from host_2 to host_1
-        # (so Host 1 learns Host 2's address)
+        print("\n🔄 Running identify protocol (Host 2 → Host 1)...")
         from libp2p.identity.identify.identify import ID as IDENTIFY_PROTOCOL_ID
 
         stream = await host_2.new_stream(host_1.get_id(), (IDENTIFY_PROTOCOL_ID,))
@@ -94,64 +246,58 @@ async def main() -> None:
         await stream.close()
 
         # Run the identify protocol from host_1 to host_2
-        # (so Host 2 learns Host 1's address)
+        print("\n🔄 Running identify protocol (Host 1 → Host 2)...")
         stream = await host_1.new_stream(host_2.get_id(), (IDENTIFY_PROTOCOL_ID,))
         response = await stream.read()
         await stream.close()
 
-        # --- NEW CODE: Update Host 1's peerstore with Host 2's addresses ---
-        from libp2p.identity.identify.pb.identify_pb2 import (
-            Identify,
-        )
-
+        # Update Host 1's peerstore with Host 2's addresses
         identify_msg = Identify()
         identify_msg.ParseFromString(response)
         peerstore_1 = host_1.get_peerstore()
         peer_id_2 = host_2.get_id()
         for addr_bytes in identify_msg.listen_addrs:
             maddr = multiaddr.Multiaddr(addr_bytes)
-            # TTL can be any positive int
-            peerstore_1.add_addr(
-                peer_id_2,
-                maddr,
-                ttl=3600,
-            )
-        # --- END NEW CODE ---
+            peerstore_1.add_addr(peer_id_2, maddr, ttl=3600)
 
-        # Now Host 1's peerstore should have Host 2's address
-        peerstore_1 = host_1.get_peerstore()
-        peer_id_2 = host_2.get_id()
-        addrs_1_for_2 = peerstore_1.addrs(peer_id_2)
-        logger.info(
-            f"[DEBUG] Host 1 peerstore addresses for Host 2 before push: "
-            f"{addrs_1_for_2}"
-        )
-        print(
-            f"[DEBUG] Host 1 peerstore addresses for Host 2 before push: "
-            f"{addrs_1_for_2}"
+        # Display peerstore information before push
+        await display_peerstore_info(
+            host_1, "Host 1", peer_id_2, "Host 2 (before push)"
         )
 
         # Push identify information from host_1 to host_2
-        logger.info("Host 1 pushing identify information to Host 2")
-        print("\nHost 1 pushing identify information to Host 2...")
+        print("\n📤 Host 1 pushing identify information to Host 2...")
 
         try:
-            # Call push_identify_to_peer which now returns a boolean
             success = await push_identify_to_peer(host_1, host_2.get_id())
 
             if success:
-                logger.info("Identify push completed successfully")
-                print("Identify push completed successfully!")
+                print("✅ Identify push completed successfully!")
             else:
-                logger.warning("Identify push didn't complete successfully")
-                print("\nWarning: Identify push didn't complete successfully")
+                print("⚠️  Identify push didn't complete successfully")
 
         except Exception as e:
-            logger.error(f"Error during identify push: {str(e)}")
-            print(f"\nError during identify push: {str(e)}")
+            print(f"❌ Error during identify push: {str(e)}")
 
-        # Add this at the end of your async with block:
-        await trio.sleep(0.5)  # Give background tasks time to finish
+        # Give a moment for the identify/push processing to complete
+        await trio.sleep(0.5)
+
+        # Display peerstore information after push
+        await display_peerstore_info(host_1, "Host 1", peer_id_2, "Host 2 (after push)")
+        await display_peerstore_info(
+            host_2, "Host 2", host_1.get_id(), "Host 1 (after push)"
+        )
+
+        # Give more time for background tasks to finish and connections to stabilize
+        print("\n⏳ Waiting for background tasks to complete...")
+        await trio.sleep(1.0)
+
+        # Gracefully close connections to prevent connection errors
+        print("🔌 Closing connections...")
+        await host_2.disconnect(host_1.get_id())
+        await trio.sleep(0.2)
+
+        print("\n🎉 Example completed successfully!")
 
 
 if __name__ == "__main__":

examples/identify_push/identify_push_listener_dialer.py

@@ -41,6 +41,9 @@ from libp2p.identity.identify import (
     ID as ID_IDENTIFY,
     identify_handler_for,
 )
+from libp2p.identity.identify.identify import (
+    _remote_address_to_multiaddr,
+)
 from libp2p.identity.identify.pb.identify_pb2 import (
     Identify,
 )
@@ -57,18 +60,46 @@ from libp2p.peer.peerinfo import (
 logger = logging.getLogger("libp2p.identity.identify-push-example")
 
 
-def custom_identify_push_handler_for(host):
+def custom_identify_push_handler_for(host, use_varint_format: bool = True):
     """
     Create a custom handler for the identify/push protocol that logs and prints
     the identity information received from the dialer.
+
+    Args:
+        host: The libp2p host
+        use_varint_format: If True, expect length-prefixed format; if False, expect
+            raw protobuf
+
     """
 
     async def handle_identify_push(stream: INetStream) -> None:
         peer_id = stream.muxed_conn.peer_id
 
+        # Get remote address information
         try:
-            # Read the identify message from the stream
-            data = await stream.read()
+            remote_address = stream.get_remote_address()
+            if remote_address:
+                observed_multiaddr = _remote_address_to_multiaddr(remote_address)
+                logger.info(
+                    "Connection from remote peer %s, address: %s, multiaddr: %s",
+                    peer_id,
+                    remote_address,
+                    observed_multiaddr,
+                )
+                print(f"\n🔗 Received identify/push request from peer: {peer_id}")
+                # Add the peer ID to create a complete multiaddr
+                complete_multiaddr = f"{observed_multiaddr}/p2p/{peer_id}"
+                print(f"   Remote address: {complete_multiaddr}")
+        except Exception as e:
+            logger.error("Error getting remote address: %s", e)
+            print(f"\n🔗 Received identify/push request from peer: {peer_id}")
+
+        try:
+            # Use the utility function to read the protobuf message
+            from libp2p.utils.varint import read_length_prefixed_protobuf
+
+            data = await read_length_prefixed_protobuf(stream, use_varint_format)
+
             identify_msg = Identify()
             identify_msg.ParseFromString(data)
 
@@ -117,11 +148,41 @@ def custom_identify_push_handler_for(host):
             await _update_peerstore_from_identify(peerstore, peer_id, identify_msg)
 
             logger.info("Successfully processed identify/push from peer %s", peer_id)
-            print(f"\nSuccessfully processed identify/push from peer {peer_id}")
+            print(f"✅ Successfully processed identify/push from peer {peer_id}")
 
         except Exception as e:
-            logger.error("Error processing identify/push from %s: %s", peer_id, e)
-            print(f"\nError processing identify/push from {peer_id}: {e}")
+            error_msg = str(e)
+            logger.error(
+                "Error processing identify/push from %s: %s", peer_id, error_msg
+            )
+            print(f"\nError processing identify/push from {peer_id}: {error_msg}")
+
+            # Check for specific format mismatch errors
+            if (
+                "Error parsing message" in error_msg
+                or "DecodeError" in error_msg
+                or "ParseFromString" in error_msg
+            ):
+                print("\n" + "=" * 60)
+                print("FORMAT MISMATCH DETECTED!")
+                print("=" * 60)
+                if use_varint_format:
+                    print(
+                        "You are using length-prefixed format (default) but the "
+                        "dialer is using raw protobuf format."
+                    )
+                    print("\nTo fix this, run the dialer with the --raw-format flag:")
+                    print(
+                        "identify-push-listener-dialer-demo --raw-format -d <ADDRESS>"
+                    )
+                else:
+                    print("You are using raw protobuf format but the dialer")
+                    print("is using length-prefixed format (default).")
+                    print(
+                        "\nTo fix this, run the dialer without the --raw-format flag:"
+                    )
+                    print("identify-push-listener-dialer-demo -d <ADDRESS>")
+                print("=" * 60)
         finally:
             # Close the stream after processing
             await stream.close()
@@ -129,9 +190,15 @@ def custom_identify_push_handler_for(host):
     return handle_identify_push
 
 
-async def run_listener(port: int) -> None:
+async def run_listener(
+    port: int, use_varint_format: bool = True, raw_format_flag: bool = False
+) -> None:
     """Run a host in listener mode."""
-    print(f"\n==== Starting Identify-Push Listener on port {port} ====\n")
+    format_name = "length-prefixed" if use_varint_format else "raw protobuf"
+    print(
+        f"\n==== Starting Identify-Push Listener on port {port} "
+        f"(using {format_name} format) ====\n"
+    )
 
     # Create key pair for the listener
     key_pair = create_new_key_pair()
@@ -139,35 +206,58 @@ async def run_listener(port: int) -> None:
     # Create the listener host
     host = new_host(key_pair=key_pair)
 
-    # Set up the identify and identify/push handlers
-    host.set_stream_handler(ID_IDENTIFY, identify_handler_for(host))
-    host.set_stream_handler(ID_IDENTIFY_PUSH, custom_identify_push_handler_for(host))
+    # Set up the identify and identify/push handlers with specified format
+    host.set_stream_handler(
+        ID_IDENTIFY, identify_handler_for(host, use_varint_format=use_varint_format)
+    )
+    host.set_stream_handler(
+        ID_IDENTIFY_PUSH,
+        custom_identify_push_handler_for(host, use_varint_format=use_varint_format),
+    )
 
     # Start listening
     listen_addr = multiaddr.Multiaddr(f"/ip4/0.0.0.0/tcp/{port}")
 
-    async with host.run([listen_addr]):
-        addr = host.get_addrs()[0]
-        logger.info("Listener host ready!")
-        print("Listener host ready!")
+    try:
+        async with host.run([listen_addr]):
+            addr = host.get_addrs()[0]
+            logger.info("Listener host ready!")
+            print("Listener host ready!")
 
-        logger.info(f"Listening on: {addr}")
-        print(f"Listening on: {addr}")
+            logger.info(f"Listening on: {addr}")
+            print(f"Listening on: {addr}")
 
-        logger.info(f"Peer ID: {host.get_id().pretty()}")
-        print(f"Peer ID: {host.get_id().pretty()}")
+            logger.info(f"Peer ID: {host.get_id().pretty()}")
+            print(f"Peer ID: {host.get_id().pretty()}")
 
-        print("\nRun dialer with command:")
-        print(f"identify-push-listener-dialer-demo -d {addr}")
-        print("\nWaiting for incoming connections... (Ctrl+C to exit)")
+            print("\nRun dialer with command:")
+            if raw_format_flag:
+                print(f"identify-push-listener-dialer-demo -d {addr} --raw-format")
+            else:
+                print(f"identify-push-listener-dialer-demo -d {addr}")
+            print("\nWaiting for incoming identify/push requests... (Ctrl+C to exit)")
 
-        # Keep running until interrupted
-        await trio.sleep_forever()
+            # Keep running until interrupted
+            try:
+                await trio.sleep_forever()
+            except KeyboardInterrupt:
+                print("\n🛑 Shutting down listener...")
+                logger.info("Listener interrupted by user")
+                return
+    except Exception as e:
+        logger.error(f"Listener error: {e}")
+        raise
 
 
-async def run_dialer(port: int, destination: str) -> None:
+async def run_dialer(
+    port: int, destination: str, use_varint_format: bool = True
+) -> None:
     """Run a host in dialer mode that connects to a listener."""
-    print(f"\n==== Starting Identify-Push Dialer on port {port} ====\n")
+    format_name = "length-prefixed" if use_varint_format else "raw protobuf"
+    print(
+        f"\n==== Starting Identify-Push Dialer on port {port} "
+        f"(using {format_name} format) ====\n"
+    )
 
     # Create key pair for the dialer
     key_pair = create_new_key_pair()
@@ -175,9 +265,14 @@ async def run_dialer(port: int, destination: str) -> None:
     # Create the dialer host
     host = new_host(key_pair=key_pair)
 
-    # Set up the identify and identify/push handlers
-    host.set_stream_handler(ID_IDENTIFY, identify_handler_for(host))
-    host.set_stream_handler(ID_IDENTIFY_PUSH, identify_push_handler_for(host))
+    # Set up the identify and identify/push handlers with specified format
+    host.set_stream_handler(
+        ID_IDENTIFY, identify_handler_for(host, use_varint_format=use_varint_format)
+    )
+    host.set_stream_handler(
+        ID_IDENTIFY_PUSH,
+        identify_push_handler_for(host, use_varint_format=use_varint_format),
+    )
 
     # Start listening on a different port
     listen_addr = multiaddr.Multiaddr(f"/ip4/0.0.0.0/tcp/{port}")
@@ -198,7 +293,9 @@ async def run_dialer(port: int, destination: str) -> None:
         try:
             await host.connect(peer_info)
             logger.info("Successfully connected to listener!")
-            print("Successfully connected to listener!")
+            print("✅ Successfully connected to listener!")
+            print(f"   Connected to: {peer_info.peer_id}")
+            print(f"   Full address: {destination}")
 
             # Push identify information to the listener
             logger.info("Pushing identify information to listener...")
@@ -206,11 +303,13 @@ async def run_dialer(port: int, destination: str) -> None:
 
             try:
                 # Call push_identify_to_peer which returns a boolean
-                success = await push_identify_to_peer(host, peer_info.peer_id)
+                success = await push_identify_to_peer(
+                    host, peer_info.peer_id, use_varint_format=use_varint_format
+                )
 
                 if success:
                     logger.info("Identify push completed successfully!")
-                    print("Identify push completed successfully!")
+                    print("✅ Identify push completed successfully!")
 
                     logger.info("Example completed successfully!")
                     print("\nExample completed successfully!")
@@ -221,17 +320,57 @@ async def run_dialer(port: int, destination: str) -> None:
                     logger.warning("Example completed with warnings.")
                     print("Example completed with warnings.")
             except Exception as e:
-                logger.error(f"Error during identify push: {str(e)}")
-                print(f"\nError during identify push: {str(e)}")
+                error_msg = str(e)
+                logger.error(f"Error during identify push: {error_msg}")
+                print(f"\nError during identify push: {error_msg}")
+
+                # Check for specific format mismatch errors
+                if (
+                    "Error parsing message" in error_msg
+                    or "DecodeError" in error_msg
+                    or "ParseFromString" in error_msg
+                ):
+                    print("\n" + "=" * 60)
+                    print("FORMAT MISMATCH DETECTED!")
+                    print("=" * 60)
+                    if use_varint_format:
+                        print(
+                            "You are using length-prefixed format (default) but the "
+                            "listener is using raw protobuf format."
+                        )
+                        print(
+                            "\nTo fix this, run the dialer with the --raw-format flag:"
+                        )
+                        print(
+                            f"identify-push-listener-dialer-demo --raw-format -d "
+                            f"{destination}"
+                        )
+                    else:
+                        print("You are using raw protobuf format but the listener")
+                        print("is using length-prefixed format (default).")
+                        print(
+                            "\nTo fix this, run the dialer without the --raw-format "
+                            "flag:"
+                        )
+                        print(f"identify-push-listener-dialer-demo -d {destination}")
+                    print("=" * 60)
 
                 logger.error("Example completed with errors.")
                 print("Example completed with errors.")
                 # Continue execution despite the push error
 
         except Exception as e:
-            logger.error(f"Error during dialer operation: {str(e)}")
-            print(f"\nError during dialer operation: {str(e)}")
-            raise
+            error_msg = str(e)
+            if "unable to connect" in error_msg or "SwarmException" in error_msg:
+                print(f"\n❌ Cannot connect to peer: {peer_info.peer_id}")
+                print(f"   Address: {destination}")
+                print(f"   Error: {error_msg}")
+                print("\n💡 Make sure the peer is running and the address is correct.")
+                return
+            else:
+                logger.error(f"Error during dialer operation: {error_msg}")
+                print(f"\nError during dialer operation: {error_msg}")
+                raise
 
 
 def main() -> None:
@@ -240,34 +379,55 @@ def main() -> None:
     This program demonstrates the libp2p identify/push protocol.
     Without arguments, it runs as a listener on random port.
     With -d parameter, it runs as a dialer on random port.
+
+    Port 0 (default) means the OS will automatically assign an available port.
+    This prevents port conflicts when running multiple instances.
+
+    Use --raw-format to send raw protobuf messages (old format) instead of
+    length-prefixed protobuf messages (new format, default).
     """
 
-    example = (
-        "/ip4/127.0.0.1/tcp/8000/p2p/QmQn4SwGkDZKkUEpBRBvTmheQycxAHJUNmVEnjA2v1qe8Q"
-    )
-
     parser = argparse.ArgumentParser(description=description)
-    parser.add_argument("-p", "--port", default=0, type=int, help="source port number")
+    parser.add_argument(
+        "-p",
+        "--port",
+        default=0,
+        type=int,
+        help="source port number (0 = random available port)",
+    )
     parser.add_argument(
         "-d",
         "--destination",
         type=str,
-        help=f"destination multiaddr string, e.g. {example}",
+        help="destination multiaddr string",
     )
+    parser.add_argument(
+        "--raw-format",
+        action="store_true",
+        help=(
+            "use raw protobuf format (old format) instead of "
+            "length-prefixed (new format)"
+        ),
+    )
+
     args = parser.parse_args()
 
+    # Determine format: raw format if --raw-format is specified, otherwise
+    # length-prefixed
+    use_varint_format = not args.raw_format
+
     try:
         if args.destination:
             # Run in dialer mode with random available port if not specified
-            trio.run(run_dialer, args.port, args.destination)
+            trio.run(run_dialer, args.port, args.destination, use_varint_format)
         else:
             # Run in listener mode with random available port if not specified
-            trio.run(run_listener, args.port)
+            trio.run(run_listener, args.port, use_varint_format, args.raw_format)
     except KeyboardInterrupt:
-        print("\nInterrupted by user")
-        logger.info("Interrupted by user")
+        print("\n👋 Goodbye!")
+        logger.info("Application interrupted by user")
     except Exception as e:
-        print(f"\nError: {str(e)}")
+        print(f"\n❌ Error: {str(e)}")
         logger.error("Error: %s", str(e))
         sys.exit(1)
 

examples/kademlia/kademlia.py

@@ -151,7 +151,10 @@ async def run_node(
         host = new_host(key_pair=key_pair)
         listen_addr = Multiaddr(f"/ip4/127.0.0.1/tcp/{port}")
 
-        async with host.run(listen_addrs=[listen_addr]):
+        async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
+            # Start the peer-store cleanup task
+            nursery.start_soon(host.get_peerstore().start_cleanup_task, 60)
+
             peer_id = host.get_id().pretty()
             addr_str = f"/ip4/127.0.0.1/tcp/{port}/p2p/{peer_id}"
             await connect_to_bootstrap_nodes(host, bootstrap_nodes)

examples/mDNS/mDNS.py

@@ -0,0 +1,77 @@
+import argparse
+import logging
+import secrets
+
+import multiaddr
+import trio
+
+from libp2p import (
+    new_host,
+)
+from libp2p.abc import PeerInfo
+from libp2p.crypto.secp256k1 import (
+    create_new_key_pair,
+)
+from libp2p.discovery.events.peerDiscovery import peerDiscovery
+
+logger = logging.getLogger("libp2p.discovery.mdns")
+logger.setLevel(logging.INFO)
+handler = logging.StreamHandler()
+handler.setFormatter(
+    logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+)
+logger.addHandler(handler)
+
+# Set root logger to DEBUG to capture all logs from dependencies
+logging.getLogger().setLevel(logging.DEBUG)
+
+
+def onPeerDiscovery(peerinfo: PeerInfo):
+    logger.info(f"Discovered: {peerinfo.peer_id}")
+
+
+async def run(port: int) -> None:
+    secret = secrets.token_bytes(32)
+    key_pair = create_new_key_pair(secret)
+    listen_addr = multiaddr.Multiaddr(f"/ip4/0.0.0.0/tcp/{port}")
+
+    peerDiscovery.register_peer_discovered_handler(onPeerDiscovery)
+
+    print(
+        "Run this from the same folder in another console to "
+        "start another peer on a different port:\n\n"
+        "mdns-demo -p <ANOTHER_PORT>\n"
+    )
+    print("Waiting for mDNS peer discovery events...\n")
+
+    logger.info("Starting peer Discovery")
+    host = new_host(key_pair=key_pair, enable_mDNS=True)
+    async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
+        # Start the peer-store cleanup task
+        nursery.start_soon(host.get_peerstore().start_cleanup_task, 60)
+
+        await trio.sleep_forever()
+
+
+def main() -> None:
+    description = """
+    This program demonstrates mDNS peer discovery using libp2p.
+    To use it, run 'mdns-demo -p <PORT>', where <PORT> is the port number.
+    Start multiple peers on different ports to see discovery in action.
+    """
+    parser = argparse.ArgumentParser(description=description)
+    parser.add_argument("-p", "--port", default=0, type=int, help="source port number")
+    parser.add_argument(
+        "-v", "--verbose", action="store_true", help="Enable verbose output"
+    )
+    args = parser.parse_args()
+    if args.verbose:
+        logger.setLevel(logging.DEBUG)
+    try:
+        trio.run(run, args.port)
+    except KeyboardInterrupt:
+        logger.info("Exiting...")
+
+
+if __name__ == "__main__":
+    main()

examples/ping/ping.py

@@ -59,6 +59,9 @@ async def run(port: int, destination: str) -> None:
     host = new_host(listen_addrs=[listen_addr])
 
     async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
+        # Start the peer-store cleanup task
+        nursery.start_soon(host.get_peerstore().start_cleanup_task, 60)
+
         if not destination:
             host.set_stream_handler(PING_PROTOCOL_ID, handle_ping)
 

examples/pubsub/pubsub.py

@@ -144,6 +144,9 @@ async def run(topic: str, destination: str | None, port: int | None) -> None:
     pubsub = Pubsub(host, gossipsub)
     termination_event = trio.Event()  # Event to signal termination
     async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
+        # Start the peer-store cleanup task
+        nursery.start_soon(host.get_peerstore().start_cleanup_task, 60)
+
         logger.info(f"Node started with peer ID: {host.get_id()}")
         logger.info(f"Listening on: {listen_addr}")
         logger.info("Initializing PubSub and GossipSub...")

libp2p/__init__.py

@@ -32,6 +32,9 @@ from libp2p.custom_types import (
     TProtocol,
     TSecurityOptions,
 )
+from libp2p.discovery.mdns.mdns import (
+    MDNSDiscovery,
+)
 from libp2p.host.basic_host import (
     BasicHost,
 )
@@ -81,6 +84,8 @@ DEFAULT_MUXER = "YAMUX"
 # Multiplexer options
 MUXER_YAMUX = "YAMUX"
 MUXER_MPLEX = "MPLEX"
+DEFAULT_NEGOTIATE_TIMEOUT = 5
+
 
 
 def set_default_muxer(muxer_name: Literal["YAMUX", "MPLEX"]) -> None:
@@ -245,6 +250,9 @@ def new_host(
     disc_opt: IPeerRouting | None = None,
     muxer_preference: Literal["YAMUX", "MPLEX"] | None = None,
     listen_addrs: Sequence[multiaddr.Multiaddr] | None = None,
+    enable_mDNS: bool = False,
+    bootstrap: list[str] | None = None,
+    negotiate_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
 ) -> IHost:
     """
     Create a new libp2p host based on the given parameters.
@@ -256,6 +264,8 @@ def new_host(
     :param disc_opt: optional discovery
     :param muxer_preference: optional explicit muxer preference
     :param listen_addrs: optional list of multiaddrs to listen on
+    :param enable_mDNS: whether to enable mDNS discovery
+    :param bootstrap: optional list of bootstrap peer addresses as strings
     :return: return a host instance
     """
     swarm = new_swarm(
@@ -268,8 +278,7 @@ def new_host(
     )
 
     if disc_opt is not None:
-        return RoutedHost(swarm, disc_opt)
-    return BasicHost(swarm)
-
+        return RoutedHost(swarm, disc_opt, enable_mDNS, bootstrap)
+    return BasicHost(network=swarm,enable_mDNS=enable_mDNS , bootstrap=bootstrap, negotitate_timeout=negotiate_timeout)
 
 __version__ = __version("libp2p")

libp2p/crypto/pb/crypto_pb2.py

@@ -13,7 +13,7 @@ _sym_db = _symbol_database.Default()
 
 
 
-DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1dlibp2p/crypto/pb/crypto.proto\x12\tcrypto.pb\"?\n\tPublicKey\x12$\n\x08key_type\x18\x01 \x02(\x0e\x32\x12.crypto.pb.KeyType\x12\x0c\n\x04\x64\x61ta\x18\x02 \x02(\x0c\"@\n\nPrivateKey\x12$\n\x08key_type\x18\x01 \x02(\x0e\x32\x12.crypto.pb.KeyType\x12\x0c\n\x04\x64\x61ta\x18\x02 \x02(\x0c*G\n\x07KeyType\x12\x07\n\x03RSA\x10\x00\x12\x0b\n\x07\x45\x64\x32\x35\x35\x31\x39\x10\x01\x12\r\n\tSecp256k1\x10\x02\x12\t\n\x05\x45\x43\x44SA\x10\x03\x12\x0c\n\x08\x45\x43\x43_P256\x10\x04')
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1dlibp2p/crypto/pb/crypto.proto\x12\tcrypto.pb\"?\n\tPublicKey\x12$\n\x08key_type\x18\x01 \x02(\x0e\x32\x12.crypto.pb.KeyType\x12\x0c\n\x04\x64\x61ta\x18\x02 \x02(\x0c\"@\n\nPrivateKey\x12$\n\x08key_type\x18\x01 \x02(\x0e\x32\x12.crypto.pb.KeyType\x12\x0c\n\x04\x64\x61ta\x18\x02 \x02(\x0c*S\n\x07KeyType\x12\x07\n\x03RSA\x10\x00\x12\x0b\n\x07\x45\x64\x32\x35\x35\x31\x39\x10\x01\x12\r\n\tSecp256k1\x10\x02\x12\t\n\x05\x45\x43\x44SA\x10\x03\x12\x0c\n\x08\x45\x43\x43_P256\x10\x04\x12\n\n\x06X25519\x10\x05')
 
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
 _builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.crypto.pb.crypto_pb2', globals())
@@ -21,7 +21,7 @@ if _descriptor._USE_C_DESCRIPTORS == False:
 
   DESCRIPTOR._options = None
   _KEYTYPE._serialized_start=175
-  _KEYTYPE._serialized_end=246
+  _KEYTYPE._serialized_end=258
   _PUBLICKEY._serialized_start=44
   _PUBLICKEY._serialized_end=107
   _PRIVATEKEY._serialized_start=109

libp2p/crypto/pb/crypto_pb2.pyi

@@ -28,6 +28,7 @@ class _KeyTypeEnumTypeWrapper(google.protobuf.internal.enum_type_wrapper._EnumTy
     Secp256k1: _KeyType.ValueType  # 2
     ECDSA: _KeyType.ValueType  # 3
     ECC_P256: _KeyType.ValueType  # 4
+    X25519: _KeyType.ValueType  # 5
 
 class KeyType(_KeyType, metaclass=_KeyTypeEnumTypeWrapper): ...
 
@@ -36,6 +37,7 @@ Ed25519: KeyType.ValueType  # 1
 Secp256k1: KeyType.ValueType  # 2
 ECDSA: KeyType.ValueType  # 3
 ECC_P256: KeyType.ValueType  # 4
+X25519: KeyType.ValueType  # 5
 global___KeyType = KeyType
 
 @typing.final

libp2p/discovery/bootstrap/__init__.py

@@ -0,0 +1,5 @@
+"""Bootstrap peer discovery module for py-libp2p."""
+
+from .bootstrap import BootstrapDiscovery
+
+__all__ = ["BootstrapDiscovery"]

libp2p/discovery/bootstrap/bootstrap.py

@@ -0,0 +1,94 @@
+import logging
+
+from multiaddr import Multiaddr
+from multiaddr.resolvers import DNSResolver
+
+from libp2p.abc import ID, INetworkService, PeerInfo
+from libp2p.discovery.bootstrap.utils import validate_bootstrap_addresses
+from libp2p.discovery.events.peerDiscovery import peerDiscovery
+from libp2p.peer.peerinfo import info_from_p2p_addr
+
+logger = logging.getLogger("libp2p.discovery.bootstrap")
+resolver = DNSResolver()
+
+
+class BootstrapDiscovery:
+    """
+    Bootstrap-based peer discovery for py-libp2p.
+    Connects to predefined bootstrap peers and adds them to peerstore.
+    """
+
+    def __init__(self, swarm: INetworkService, bootstrap_addrs: list[str]):
+        self.swarm = swarm
+        self.peerstore = swarm.peerstore
+        self.bootstrap_addrs = bootstrap_addrs or []
+        self.discovered_peers: set[str] = set()
+
+    async def start(self) -> None:
+        """Process bootstrap addresses and emit peer discovery events."""
+        logger.debug(
+            f"Starting bootstrap discovery with "
+            f"{len(self.bootstrap_addrs)} bootstrap addresses"
+        )
+
+        # Validate and filter bootstrap addresses
+        self.bootstrap_addrs = validate_bootstrap_addresses(self.bootstrap_addrs)
+
+        for addr_str in self.bootstrap_addrs:
+            try:
+                await self._process_bootstrap_addr(addr_str)
+            except Exception as e:
+                logger.debug(f"Failed to process bootstrap address {addr_str}: {e}")
+
+    def stop(self) -> None:
+        """Clean up bootstrap discovery resources."""
+        logger.debug("Stopping bootstrap discovery")
+        self.discovered_peers.clear()
+
+    async def _process_bootstrap_addr(self, addr_str: str) -> None:
+        """Convert string address to PeerInfo and add to peerstore."""
+        try:
+            multiaddr = Multiaddr(addr_str)
+        except Exception as e:
+            logger.debug(f"Invalid multiaddr format '{addr_str}': {e}")
+            return
+        if self.is_dns_addr(multiaddr):
+            resolved_addrs = await resolver.resolve(multiaddr)
+            peer_id_str = multiaddr.get_peer_id()
+            if peer_id_str is None:
+                logger.warning(f"Missing peer ID in DNS address: {addr_str}")
+                return
+            peer_id = ID.from_base58(peer_id_str)
+            addrs = [addr for addr in resolved_addrs]
+            if not addrs:
+                logger.warning(f"No addresses resolved for DNS address: {addr_str}")
+                return
+            peer_info = PeerInfo(peer_id, addrs)
+            self.add_addr(peer_info)
+        else:
+            self.add_addr(info_from_p2p_addr(multiaddr))
+
+    def is_dns_addr(self, addr: Multiaddr) -> bool:
+        """Check if the address is a DNS address."""
+        return any(protocol.name == "dnsaddr" for protocol in addr.protocols())
+
+    def add_addr(self, peer_info: PeerInfo) -> None:
+        """Add a peer to the peerstore and emit discovery event."""
+        # Skip if it's our own peer
+        if peer_info.peer_id == self.swarm.get_peer_id():
+            logger.debug(f"Skipping own peer ID: {peer_info.peer_id}")
+            return
+
+        # Always add addresses to peerstore (allows multiple addresses for same peer)
+        self.peerstore.add_addrs(peer_info.peer_id, peer_info.addrs, 10)
+
+        # Only emit discovery event if this is the first time we see this peer
+        peer_id_str = str(peer_info.peer_id)
+        if peer_id_str not in self.discovered_peers:
+            # Track discovered peer
+            self.discovered_peers.add(peer_id_str)
+            # Emit peer discovery event
+            peerDiscovery.emit_peer_discovered(peer_info)
+            logger.debug(f"Peer discovered: {peer_info.peer_id}")
+        else:
+            logger.debug(f"Additional addresses added for peer: {peer_info.peer_id}")

libp2p/discovery/bootstrap/utils.py

@@ -0,0 +1,51 @@
+"""Utility functions for bootstrap discovery."""
+
+import logging
+
+from multiaddr import Multiaddr
+
+from libp2p.peer.peerinfo import InvalidAddrError, PeerInfo, info_from_p2p_addr
+
+logger = logging.getLogger("libp2p.discovery.bootstrap.utils")
+
+
+def validate_bootstrap_addresses(addrs: list[str]) -> list[str]:
+    """
+    Validate and filter bootstrap addresses.
+
+    :param addrs: List of bootstrap address strings
+    :return: List of valid bootstrap addresses
+    """
+    valid_addrs = []
+
+    for addr_str in addrs:
+        try:
+            # Try to parse as multiaddr
+            multiaddr = Multiaddr(addr_str)
+
+            # Try to extract peer info (this validates the p2p component)
+            info_from_p2p_addr(multiaddr)
+
+            valid_addrs.append(addr_str)
+            logger.debug(f"Valid bootstrap address: {addr_str}")
+
+        except (InvalidAddrError, ValueError, Exception) as e:
+            logger.warning(f"Invalid bootstrap address '{addr_str}': {e}")
+            continue
+
+    return valid_addrs
+
+
+def parse_bootstrap_peer_info(addr_str: str) -> PeerInfo | None:
+    """
+    Parse bootstrap address string into PeerInfo.
+
+    :param addr_str: Bootstrap address string
+    :return: PeerInfo object or None if parsing fails
+    """
+    try:
+        multiaddr = Multiaddr(addr_str)
+        return info_from_p2p_addr(multiaddr)
+    except Exception as e:
+        logger.error(f"Failed to parse bootstrap address '{addr_str}': {e}")
+        return None

libp2p/discovery/events/peerDiscovery.py

@@ -0,0 +1,26 @@
+from collections.abc import (
+    Callable,
+)
+
+from libp2p.abc import (
+    PeerInfo,
+)
+
+TTL: int = 60 * 60  # Time-to-live for discovered peers in seconds
+
+
+class PeerDiscovery:
+    def __init__(self) -> None:
+        self._peer_discovered_handlers: list[Callable[[PeerInfo], None]] = []
+
+    def register_peer_discovered_handler(
+        self, handler: Callable[[PeerInfo], None]
+    ) -> None:
+        self._peer_discovered_handlers.append(handler)
+
+    def emit_peer_discovered(self, peer_info: PeerInfo) -> None:
+        for handler in self._peer_discovered_handlers:
+            handler(peer_info)
+
+
+peerDiscovery = PeerDiscovery()

libp2p/discovery/mdns/broadcaster.py

@@ -0,0 +1,91 @@
+import logging
+import socket
+
+from zeroconf import (
+    EventLoopBlocked,
+    ServiceInfo,
+    Zeroconf,
+)
+
+logger = logging.getLogger("libp2p.discovery.mdns.broadcaster")
+
+
+class PeerBroadcaster:
+    """
+    Broadcasts this peer's presence on the local network using mDNS/zeroconf.
+    Registers a service with the peer's ID in the TXT record as per libp2p spec.
+    """
+
+    def __init__(
+        self,
+        zeroconf: Zeroconf,
+        service_type: str,
+        service_name: str,
+        peer_id: str,
+        port: int,
+    ):
+        self.zeroconf = zeroconf
+        self.service_type = service_type
+        self.peer_id = peer_id
+        self.port = port
+        self.service_name = service_name
+
+        # Get the local IP address
+        local_ip = self._get_local_ip()
+        hostname = socket.gethostname()
+
+        self.service_info = ServiceInfo(
+            type_=self.service_type,
+            name=self.service_name,
+            port=self.port,
+            properties={b"id": self.peer_id.encode()},
+            server=f"{hostname}.local.",
+            addresses=[socket.inet_aton(local_ip)],
+        )
+
+    def _get_local_ip(self) -> str:
+        """Get the local IP address of this machine"""
+        try:
+            # Connect to a remote address to determine the local IP
+            # This doesn't actually send data
+            with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as s:
+                s.connect(("8.8.8.8", 80))
+                local_ip = s.getsockname()[0]
+            return local_ip
+        except Exception:
+            # Fallback to localhost if we can't determine the IP
+            return "127.0.0.1"
+
+    def register(self) -> None:
+        """Register the peer's mDNS service on the network."""
+        try:
+            self.zeroconf.register_service(self.service_info)
+            logger.debug(f"mDNS service registered: {self.service_name}")
+        except EventLoopBlocked as e:
+            logger.warning(
+                "EventLoopBlocked while registering mDNS '%s': %s", self.service_name, e
+            )
+        except Exception as e:
+            logger.error(
+                "Unexpected error during mDNS registration for '%s': %r",
+                self.service_name,
+                e,
+            )
+
+    def unregister(self) -> None:
+        """Unregister the peer's mDNS service from the network."""
+        try:
+            self.zeroconf.unregister_service(self.service_info)
+            logger.debug(f"mDNS service unregistered: {self.service_name}")
+        except EventLoopBlocked as e:
+            logger.warning(
+                "EventLoopBlocked while unregistering mDNS '%s': %s",
+                self.service_name,
+                e,
+            )
+        except Exception as e:
+            logger.error(
+                "Unexpected error during mDNS unregistration for '%s': %r",
+                self.service_name,
+                e,
+            )

libp2p/discovery/mdns/listener.py

@@ -0,0 +1,83 @@
+import logging
+import socket
+
+from zeroconf import (
+    ServiceBrowser,
+    ServiceInfo,
+    ServiceListener,
+    Zeroconf,
+)
+
+from libp2p.abc import IPeerStore, Multiaddr
+from libp2p.discovery.events.peerDiscovery import peerDiscovery
+from libp2p.peer.id import ID
+from libp2p.peer.peerinfo import PeerInfo
+
+logger = logging.getLogger("libp2p.discovery.mdns.listener")
+
+
+class PeerListener(ServiceListener):
+    """mDNS listener — now a true ServiceListener subclass."""
+
+    def __init__(
+        self,
+        peerstore: IPeerStore,
+        zeroconf: Zeroconf,
+        service_type: str,
+        service_name: str,
+    ) -> None:
+        self.peerstore = peerstore
+        self.zeroconf = zeroconf
+        self.service_type = service_type
+        self.service_name = service_name
+        self.discovered_services: dict[str, ID] = {}
+        self.browser = ServiceBrowser(self.zeroconf, self.service_type, listener=self)
+
+    def add_service(self, zc: Zeroconf, type_: str, name: str) -> None:
+        if name == self.service_name:
+            return
+        logger.debug(f"Adding service: {name}")
+        info = zc.get_service_info(type_, name, timeout=5000)
+        if not info:
+            return
+        peer_info = self._extract_peer_info(info)
+        if peer_info:
+            self.discovered_services[name] = peer_info.peer_id
+            self.peerstore.add_addrs(peer_info.peer_id, peer_info.addrs, 10)
+            peerDiscovery.emit_peer_discovered(peer_info)
+            logger.debug(f"Discovered Peer: {peer_info.peer_id}")
+
+    def remove_service(self, zc: Zeroconf, type_: str, name: str) -> None:
+        if name == self.service_name:
+            return
+        logger.debug(f"Removing service: {name}")
+        peer_id = self.discovered_services.pop(name)
+        self.peerstore.clear_addrs(peer_id)
+        logger.debug(f"Removed Peer: {peer_id}")
+
+    def update_service(self, zc: Zeroconf, type_: str, name: str) -> None:
+        info = zc.get_service_info(type_, name, timeout=5000)
+        if not info:
+            return
+        peer_info = self._extract_peer_info(info)
+        if peer_info:
+            self.peerstore.clear_addrs(peer_info.peer_id)
+            self.peerstore.add_addrs(peer_info.peer_id, peer_info.addrs, 10)
+            logger.debug(f"Updated Peer {peer_info.peer_id}")
+
+    def _extract_peer_info(self, info: ServiceInfo) -> PeerInfo | None:
+        try:
+            addrs = [
+                Multiaddr(f"/ip4/{socket.inet_ntoa(addr)}/tcp/{info.port}")
+                for addr in info.addresses
+            ]
+            pid_bytes = info.properties.get(b"id")
+            if not pid_bytes:
+                return None
+            pid = ID.from_base58(pid_bytes.decode())
+            return PeerInfo(peer_id=pid, addrs=addrs)
+        except Exception:
+            return None
+
+    def stop(self) -> None:
+        self.browser.cancel()

libp2p/discovery/mdns/mdns.py

@@ -0,0 +1,73 @@
+"""
+mDNS-based peer discovery for py-libp2p.
+Conforms to https://github.com/libp2p/specs/blob/master/discovery/mdns.md
+Uses zeroconf for mDNS broadcast/listen. Async operations use trio.
+"""
+
+import logging
+
+from zeroconf import (
+    Zeroconf,
+)
+
+from libp2p.abc import (
+    INetworkService,
+)
+
+from .broadcaster import (
+    PeerBroadcaster,
+)
+from .listener import (
+    PeerListener,
+)
+from .utils import (
+    stringGen,
+)
+
+logger = logging.getLogger("libp2p.discovery.mdns")
+
+SERVICE_TYPE = "_p2p._udp.local."
+MCAST_PORT = 5353
+MCAST_ADDR = "224.0.0.251"
+
+
+class MDNSDiscovery:
+    """
+    mDNS-based peer discovery for py-libp2p, using zeroconf.
+    Conforms to the libp2p mDNS discovery spec.
+    """
+
+    def __init__(self, swarm: INetworkService, port: int = 8000):
+        self.peer_id = str(swarm.get_peer_id())
+        self.port = port
+        self.zeroconf = Zeroconf()
+        self.serviceName = f"{stringGen()}.{SERVICE_TYPE}"
+        self.peerstore = swarm.peerstore
+        self.swarm = swarm
+        self.broadcaster = PeerBroadcaster(
+            zeroconf=self.zeroconf,
+            service_type=SERVICE_TYPE,
+            service_name=self.serviceName,
+            peer_id=self.peer_id,
+            port=self.port,
+        )
+        self.listener = PeerListener(
+            zeroconf=self.zeroconf,
+            peerstore=self.peerstore,
+            service_type=SERVICE_TYPE,
+            service_name=self.serviceName,
+        )
+
+    def start(self) -> None:
+        """Register this peer and start listening for others."""
+        logger.debug(
+            f"Starting mDNS discovery for peer {self.peer_id} on port {self.port}"
+        )
+        self.broadcaster.register()
+        # Listener is started in constructor
+
+    def stop(self) -> None:
+        """Unregister this peer and clean up zeroconf resources."""
+        logger.debug("Stopping mDNS discovery")
+        self.broadcaster.unregister()
+        self.zeroconf.close()

libp2p/discovery/mdns/utils.py

@@ -0,0 +1,11 @@
+import random
+import string
+
+
+def stringGen(len: int = 63) -> str:
+    """Generate a random string of lowercase letters and digits."""
+    charset = string.ascii_lowercase + string.digits
+    result = []
+    for _ in range(len):
+        result.append(random.choice(charset))
+    return "".join(result)

libp2p/host/basic_host.py

@@ -29,6 +29,8 @@ from libp2p.custom_types import (
     StreamHandlerFn,
     TProtocol,
 )
+from libp2p.discovery.bootstrap.bootstrap import BootstrapDiscovery
+from libp2p.discovery.mdns.mdns import MDNSDiscovery
 from libp2p.host.defaults import (
     get_default_protocols,
 )
@@ -70,6 +72,7 @@ if TYPE_CHECKING:
 
 
 logger = logging.getLogger("libp2p.network.basic_host")
+DEFAULT_NEGOTIATE_TIMEOUT = 5
 
 
 class BasicHost(IHost):
@@ -89,15 +92,23 @@ class BasicHost(IHost):
     def __init__(
         self,
         network: INetworkService,
+        enable_mDNS: bool = False,
+        bootstrap: list[str] | None = None,
         default_protocols: Optional["OrderedDict[TProtocol, StreamHandlerFn]"] = None,
+        negotitate_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
     ) -> None:
         self._network = network
         self._network.set_stream_handler(self._swarm_stream_handler)
         self.peerstore = self._network.peerstore
+        self.negotiate_timeout = negotitate_timeout
         # Protocol muxing
         default_protocols = default_protocols or get_default_protocols(self)
         self.multiselect = Multiselect(dict(default_protocols.items()))
         self.multiselect_client = MultiselectClient()
+        if enable_mDNS:
+            self.mDNS = MDNSDiscovery(network)
+        if bootstrap:
+            self.bootstrap = BootstrapDiscovery(network, bootstrap)
 
     def get_id(self) -> ID:
         """
@@ -162,7 +173,19 @@ class BasicHost(IHost):
             network = self.get_network()
             async with background_trio_service(network):
                 await network.listen(*listen_addrs)
-                yield
+                if hasattr(self, "mDNS") and self.mDNS is not None:
+                    logger.debug("Starting mDNS Discovery")
+                    self.mDNS.start()
+                if hasattr(self, "bootstrap") and self.bootstrap is not None:
+                    logger.debug("Starting Bootstrap Discovery")
+                    await self.bootstrap.start()
+                try:
+                    yield
+                finally:
+                    if hasattr(self, "mDNS") and self.mDNS is not None:
+                        self.mDNS.stop()
+                    if hasattr(self, "bootstrap") and self.bootstrap is not None:
+                        self.bootstrap.stop()
 
         return _run()
 
@@ -178,7 +201,10 @@ class BasicHost(IHost):
         self.multiselect.add_handler(protocol_id, stream_handler)
 
     async def new_stream(
-        self, peer_id: ID, protocol_ids: Sequence[TProtocol]
+        self,
+        peer_id: ID,
+        protocol_ids: Sequence[TProtocol],
+        negotitate_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
     ) -> INetStream:
         """
         :param peer_id: peer_id that host is connecting
@@ -190,7 +216,9 @@ class BasicHost(IHost):
         # Perform protocol muxing to determine protocol to use
         try:
             selected_protocol = await self.multiselect_client.select_one_of(
-                list(protocol_ids), MultiselectCommunicator(net_stream)
+                list(protocol_ids),
+                MultiselectCommunicator(net_stream),
+                negotitate_timeout,
             )
         except MultiselectClientError as error:
             logger.debug("fail to open a stream to peer %s, error=%s", peer_id, error)
@@ -200,7 +228,12 @@ class BasicHost(IHost):
         net_stream.set_protocol(selected_protocol)
         return net_stream
 
-    async def send_command(self, peer_id: ID, command: str) -> list[str]:
+    async def send_command(
+        self,
+        peer_id: ID,
+        command: str,
+        response_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
+    ) -> list[str]:
         """
         Send a multistream-select command to the specified peer and return
         the response.
@@ -214,7 +247,7 @@ class BasicHost(IHost):
 
         try:
             response = await self.multiselect_client.query_multistream_command(
-                MultiselectCommunicator(new_stream), command
+                MultiselectCommunicator(new_stream), command, response_timeout
             )
         except MultiselectClientError as error:
             logger.debug("fail to open a stream to peer %s, error=%s", peer_id, error)
@@ -253,7 +286,7 @@ class BasicHost(IHost):
         # Perform protocol muxing to determine protocol to use
         try:
             protocol, handler = await self.multiselect.negotiate(
-                MultiselectCommunicator(net_stream)
+                MultiselectCommunicator(net_stream), self.negotiate_timeout
             )
         except MultiselectError as error:
             peer_id = net_stream.muxed_conn.peer_id

libp2p/host/defaults.py

@@ -26,5 +26,8 @@ if TYPE_CHECKING:
 
 def get_default_protocols(host: IHost) -> "OrderedDict[TProtocol, StreamHandlerFn]":
     return OrderedDict(
-        ((IdentifyID, identify_handler_for(host)), (PingID, handle_ping))
+        (
+            (IdentifyID, identify_handler_for(host, use_varint_format=True)),
+            (PingID, handle_ping),
+        )
     )

libp2p/host/routed_host.py

@@ -18,8 +18,14 @@ from libp2p.peer.peerinfo import (
 class RoutedHost(BasicHost):
     _router: IPeerRouting
 
-    def __init__(self, network: INetworkService, router: IPeerRouting):
-        super().__init__(network)
+    def __init__(
+        self,
+        network: INetworkService,
+        router: IPeerRouting,
+        enable_mDNS: bool = False,
+        bootstrap: list[str] | None = None,
+    ):
+        super().__init__(network, enable_mDNS, bootstrap)
         self._router = router
 
     async def connect(self, peer_info: PeerInfo) -> None:

libp2p/identity/identify/identify.py

@@ -15,8 +15,12 @@ from libp2p.custom_types import (
 from libp2p.network.stream.exceptions import (
     StreamClosed,
 )
+from libp2p.peer.envelope import seal_record
+from libp2p.peer.peer_record import PeerRecord
 from libp2p.utils import (
+    decode_varint_with_size,
     get_agent_version,
+    varint,
 )
 
 from .pb.identify_pb2 import (
@@ -59,7 +63,12 @@ def _mk_identify_protobuf(
 ) -> Identify:
     public_key = host.get_public_key()
     laddrs = host.get_addrs()
-    protocols = host.get_mux().get_protocols()
+    protocols = tuple(str(p) for p in host.get_mux().get_protocols() if p is not None)
+
+    # Create a signed peer-record for the remote peer
+    record = PeerRecord(host.get_id(), host.get_addrs())
+    envelope = seal_record(record, host.get_private_key())
+    protobuf = envelope.marshal_envelope()
 
     observed_addr = observed_multiaddr.to_bytes() if observed_multiaddr else b""
     return Identify(
@@ -69,10 +78,51 @@ def _mk_identify_protobuf(
         listen_addrs=map(_multiaddr_to_bytes, laddrs),
         observed_addr=observed_addr,
         protocols=protocols,
+        signedPeerRecord=protobuf,
     )
 
 
-def identify_handler_for(host: IHost) -> StreamHandlerFn:
+def parse_identify_response(response: bytes) -> Identify:
+    """
+    Parse identify response that could be either:
+    - Old format: raw protobuf
+    - New format: length-prefixed protobuf
+
+    This function provides backward and forward compatibility.
+    """
+    # Try new format first: length-prefixed protobuf
+    if len(response) >= 1:
+        length, varint_size = decode_varint_with_size(response)
+        if varint_size > 0 and length > 0 and varint_size + length <= len(response):
+            protobuf_data = response[varint_size : varint_size + length]
+            try:
+                identify_response = Identify()
+                identify_response.ParseFromString(protobuf_data)
+                # Sanity check: must have agent_version (protocol_version is optional)
+                if identify_response.agent_version:
+                    logger.debug(
+                        "Parsed length-prefixed identify response (new format)"
+                    )
+                    return identify_response
+            except Exception:
+                pass  # Fall through to old format
+
+    # Fall back to old format: raw protobuf
+    try:
+        identify_response = Identify()
+        identify_response.ParseFromString(response)
+        logger.debug("Parsed raw protobuf identify response (old format)")
+        return identify_response
+    except Exception as e:
+        logger.error(f"Failed to parse identify response: {e}")
+        logger.error(f"Response length: {len(response)}")
+        logger.error(f"Response hex: {response.hex()}")
+        raise
+
+
+def identify_handler_for(
+    host: IHost, use_varint_format: bool = True
+) -> StreamHandlerFn:
     async def handle_identify(stream: INetStream) -> None:
         # get observed address from ``stream``
         peer_id = (
@@ -100,7 +150,21 @@ def identify_handler_for(host: IHost) -> StreamHandlerFn:
         response = protobuf.SerializeToString()
 
         try:
-            await stream.write(response)
+            if use_varint_format:
+                # Send length-prefixed protobuf message (new format)
+                await stream.write(varint.encode_uvarint(len(response)))
+                await stream.write(response)
+                logger.debug(
+                    "Sent new format (length-prefixed) identify response to %s",
+                    peer_id,
+                )
+            else:
+                # Send raw protobuf message (old format for backward compatibility)
+                await stream.write(response)
+                logger.debug(
+                    "Sent old format (raw protobuf) identify response to %s",
+                    peer_id,
+                )
         except StreamClosed:
             logger.debug("Fail to respond to %s request: stream closed", ID)
         else:

libp2p/identity/identify/pb/identify.proto

@@ -9,4 +9,5 @@ message Identify {
   repeated bytes listen_addrs = 2;
   optional bytes observed_addr = 4;
   repeated string protocols = 3;
+  optional bytes signedPeerRecord = 8;
 }

libp2p/identity/identify/pb/identify_pb2.py

@@ -13,7 +13,7 @@ _sym_db = _symbol_database.Default()
 
 
 
-DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n*libp2p/identity/identify/pb/identify.proto\x12\x0bidentify.pb\"\x8f\x01\n\x08Identify\x12\x18\n\x10protocol_version\x18\x05 \x01(\t\x12\x15\n\ragent_version\x18\x06 \x01(\t\x12\x12\n\npublic_key\x18\x01 \x01(\x0c\x12\x14\n\x0clisten_addrs\x18\x02 \x03(\x0c\x12\x15\n\robserved_addr\x18\x04 \x01(\x0c\x12\x11\n\tprotocols\x18\x03 \x03(\t')
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n*libp2p/identity/identify/pb/identify.proto\x12\x0bidentify.pb\"\xa9\x01\n\x08Identify\x12\x18\n\x10protocol_version\x18\x05 \x01(\t\x12\x15\n\ragent_version\x18\x06 \x01(\t\x12\x12\n\npublic_key\x18\x01 \x01(\x0c\x12\x14\n\x0clisten_addrs\x18\x02 \x03(\x0c\x12\x15\n\robserved_addr\x18\x04 \x01(\x0c\x12\x11\n\tprotocols\x18\x03 \x03(\t\x12\x18\n\x10signedPeerRecord\x18\x08 \x01(\x0c')
 
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
 _builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.identity.identify.pb.identify_pb2', globals())
@@ -21,5 +21,5 @@ if _descriptor._USE_C_DESCRIPTORS == False:
 
   DESCRIPTOR._options = None
   _IDENTIFY._serialized_start=60
-  _IDENTIFY._serialized_end=203
+  _IDENTIFY._serialized_end=229
 # @@protoc_insertion_point(module_scope)

libp2p/identity/identify/pb/identify_pb2.pyi

@@ -22,10 +22,12 @@ class Identify(google.protobuf.message.Message):
     LISTEN_ADDRS_FIELD_NUMBER: builtins.int
     OBSERVED_ADDR_FIELD_NUMBER: builtins.int
     PROTOCOLS_FIELD_NUMBER: builtins.int
+    SIGNEDPEERRECORD_FIELD_NUMBER: builtins.int
     protocol_version: builtins.str
     agent_version: builtins.str
     public_key: builtins.bytes
     observed_addr: builtins.bytes
+    signedPeerRecord: builtins.bytes
     @property
     def listen_addrs(self) -> google.protobuf.internal.containers.RepeatedScalarFieldContainer[builtins.bytes]: ...
     @property
@@ -39,8 +41,9 @@ class Identify(google.protobuf.message.Message):
         listen_addrs: collections.abc.Iterable[builtins.bytes] | None = ...,
         observed_addr: builtins.bytes | None = ...,
         protocols: collections.abc.Iterable[builtins.str] | None = ...,
+        signedPeerRecord: builtins.bytes | None = ...,
     ) -> None: ...
-    def HasField(self, field_name: typing.Literal["agent_version", b"agent_version", "observed_addr", b"observed_addr", "protocol_version", b"protocol_version", "public_key", b"public_key"]) -> builtins.bool: ...
-    def ClearField(self, field_name: typing.Literal["agent_version", b"agent_version", "listen_addrs", b"listen_addrs", "observed_addr", b"observed_addr", "protocol_version", b"protocol_version", "protocols", b"protocols", "public_key", b"public_key"]) -> None: ...
+    def HasField(self, field_name: typing.Literal["agent_version", b"agent_version", "observed_addr", b"observed_addr", "protocol_version", b"protocol_version", "public_key", b"public_key", "signedPeerRecord", b"signedPeerRecord"]) -> builtins.bool: ...
+    def ClearField(self, field_name: typing.Literal["agent_version", b"agent_version", "listen_addrs", b"listen_addrs", "observed_addr", b"observed_addr", "protocol_version", b"protocol_version", "protocols", b"protocols", "public_key", b"public_key", "signedPeerRecord", b"signedPeerRecord"]) -> None: ...
 
 global___Identify = Identify

libp2p/identity/identify_push/identify_push.py

@@ -20,11 +20,16 @@ from libp2p.custom_types import (
 from libp2p.network.stream.exceptions import (
     StreamClosed,
 )
+from libp2p.peer.envelope import consume_envelope
 from libp2p.peer.id import (
     ID,
 )
 from libp2p.utils import (
     get_agent_version,
+    varint,
+)
+from libp2p.utils.varint import (
+    read_length_prefixed_protobuf,
 )
 
 from ..identify.identify import (
@@ -40,22 +45,31 @@ logger = logging.getLogger(__name__)
 ID_PUSH = TProtocol("/ipfs/id/push/1.0.0")
 PROTOCOL_VERSION = "ipfs/0.1.0"
 AGENT_VERSION = get_agent_version()
+CONCURRENCY_LIMIT = 10
 
 
-def identify_push_handler_for(host: IHost) -> StreamHandlerFn:
+def identify_push_handler_for(
+    host: IHost, use_varint_format: bool = True
+) -> StreamHandlerFn:
     """
     Create a handler for the identify/push protocol.
 
     This handler receives pushed identify messages from remote peers and updates
     the local peerstore with the new information.
+
+    Args:
+        host: The libp2p host.
+        use_varint_format: True=length-prefixed, False=raw protobuf.
+
     """
 
     async def handle_identify_push(stream: INetStream) -> None:
         peer_id = stream.muxed_conn.peer_id
 
         try:
-            # Read the identify message from the stream
-            data = await stream.read()
+            # Use the utility function to read the protobuf message
+            data = await read_length_prefixed_protobuf(stream, use_varint_format)
+
             identify_msg = Identify()
             identify_msg.ParseFromString(data)
 
@@ -65,6 +79,11 @@ def identify_push_handler_for(host: IHost) -> StreamHandlerFn:
             )
 
             logger.debug("Successfully processed identify/push from peer %s", peer_id)
+
+            # Send acknowledgment to indicate successful processing
+            # This ensures the sender knows the message was received before closing
+            await stream.write(b"OK")
+
         except StreamClosed:
             logger.debug(
                 "Stream closed while processing identify/push from %s", peer_id
@@ -73,7 +92,10 @@ def identify_push_handler_for(host: IHost) -> StreamHandlerFn:
             logger.error("Error processing identify/push from %s: %s", peer_id, e)
         finally:
             # Close the stream after processing
-            await stream.close()
+            try:
+                await stream.close()
+            except Exception:
+                pass  # Ignore errors when closing
 
     return handle_identify_push
 
@@ -119,6 +141,19 @@ async def _update_peerstore_from_identify(
         except Exception as e:
             logger.error("Error updating protocols for peer %s: %s", peer_id, e)
 
+    if identify_msg.HasField("signedPeerRecord"):
+        try:
+            # Convert the signed-peer-record(Envelope) from prtobuf bytes
+            envelope, _ = consume_envelope(
+                identify_msg.signedPeerRecord, "libp2p-peer-record"
+            )
+            # Use a default TTL of 2 hours (7200 seconds)
+            if not peerstore.consume_peer_record(envelope, 7200):
+                logger.error("Updating Certified-Addr-Book was unsuccessful")
+        except Exception as e:
+            logger.error(
+                "Error updating the certified addr book for peer %s: %s", peer_id, e
+            )
     # Update observed address if present
     if identify_msg.HasField("observed_addr") and identify_msg.observed_addr:
         try:
@@ -132,7 +167,11 @@ async def _update_peerstore_from_identify(
 
 
 async def push_identify_to_peer(
-    host: IHost, peer_id: ID, observed_multiaddr: Multiaddr | None = None
+    host: IHost,
+    peer_id: ID,
+    observed_multiaddr: Multiaddr | None = None,
+    limit: trio.Semaphore = trio.Semaphore(CONCURRENCY_LIMIT),
+    use_varint_format: bool = True,
 ) -> bool:
     """
     Push an identify message to a specific peer.
@@ -140,52 +179,91 @@ async def push_identify_to_peer(
     This function opens a stream to the peer using the identify/push protocol,
     sends the identify message, and closes the stream.
 
-    Returns
-    -------
-    bool
-        True if the push was successful, False otherwise.
+    Args:
+        host: The libp2p host.
+        peer_id: The peer ID to push to.
+        observed_multiaddr: The observed multiaddress (optional).
+        limit: Semaphore for concurrency control.
+        use_varint_format: True=length-prefixed, False=raw protobuf.
+
+    Returns:
+        bool: True if the push was successful, False otherwise.
 
     """
-    try:
-        # Create a new stream to the peer using the identify/push protocol
-        stream = await host.new_stream(peer_id, [ID_PUSH])
+    async with limit:
+        try:
+            # Create a new stream to the peer using the identify/push protocol
+            stream = await host.new_stream(peer_id, [ID_PUSH])
 
-        # Create the identify message
-        identify_msg = _mk_identify_protobuf(host, observed_multiaddr)
-        response = identify_msg.SerializeToString()
+            # Create the identify message
+            identify_msg = _mk_identify_protobuf(host, observed_multiaddr)
+            response = identify_msg.SerializeToString()
 
-        # Send the identify message
-        await stream.write(response)
+            if use_varint_format:
+                # Send length-prefixed identify message
+                await stream.write(varint.encode_uvarint(len(response)))
+                await stream.write(response)
+            else:
+                # Send raw protobuf message
+                await stream.write(response)
 
-        # Close the stream
-        await stream.close()
+            # Wait for acknowledgment from the receiver with timeout
+            # This ensures the message was processed before closing
+            try:
+                with trio.move_on_after(1.0):  # 1 second timeout
+                    ack = await stream.read(2)  # Read "OK" acknowledgment
+                    if ack != b"OK":
+                        logger.warning(
+                            "Unexpected acknowledgment from peer %s: %s", peer_id, ack
+                        )
+            except Exception as e:
+                logger.debug("No acknowledgment received from peer %s: %s", peer_id, e)
+                # Continue anyway, as the message might have been processed
 
-        logger.debug("Successfully pushed identify to peer %s", peer_id)
-        return True
-    except Exception as e:
-        logger.error("Error pushing identify to peer %s: %s", peer_id, e)
-        return False
+            # Close the stream after acknowledgment (or timeout)
+            await stream.close()
+
+            logger.debug("Successfully pushed identify to peer %s", peer_id)
+            return True
+        except Exception as e:
+            logger.error("Error pushing identify to peer %s: %s", peer_id, e)
+            return False
 
 
 async def push_identify_to_peers(
     host: IHost,
     peer_ids: set[ID] | None = None,
     observed_multiaddr: Multiaddr | None = None,
+    use_varint_format: bool = True,
 ) -> None:
     """
     Push an identify message to multiple peers in parallel.
 
     If peer_ids is None, push to all connected peers.
+
+    Args:
+        host: The libp2p host.
+        peer_ids: Set of peer IDs to push to (if None, push to all connected peers).
+        observed_multiaddr: The observed multiaddress (optional).
+        use_varint_format: True=length-prefixed, False=raw protobuf.
+
     """
     if peer_ids is None:
         # Get all connected peers
-        peer_ids = set(host.get_peerstore().peer_ids())
+        peer_ids = set(host.get_connected_peers())
+
+    # Create a single shared semaphore for concurrency control
+    limit = trio.Semaphore(CONCURRENCY_LIMIT)
 
     # Push to each peer in parallel using a trio.Nursery
-    # TODO: Consider using a bounded nursery to limit concurrency
-    # and avoid overwhelming the network. This can be done by using
-    # trio.open_nursery(max_concurrent=10) or similar.
-    # For now, we will use an unbounded nursery for simplicity.
+    # limiting concurrent connections to CONCURRENCY_LIMIT
     async with trio.open_nursery() as nursery:
         for peer_id in peer_ids:
-            nursery.start_soon(push_identify_to_peer, host, peer_id, observed_multiaddr)
+            nursery.start_soon(
+                push_identify_to_peer,
+                host,
+                peer_id,
+                observed_multiaddr,
+                limit,
+                use_varint_format,
+            )

libp2p/kad_dht/pb/kademlia_pb2.py

@@ -2,10 +2,10 @@
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
 # source: libp2p/kad_dht/pb/kademlia.proto
 """Generated protocol buffer code."""
+from google.protobuf.internal import builder as _builder
 from google.protobuf import descriptor as _descriptor
 from google.protobuf import descriptor_pool as _descriptor_pool
 from google.protobuf import symbol_database as _symbol_database
-from google.protobuf.internal import builder as _builder
 # @@protoc_insertion_point(imports)
 
 _sym_db = _symbol_database.Default()
@@ -15,19 +15,19 @@ _sym_db = _symbol_database.Default()
 
 DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n libp2p/kad_dht/pb/kademlia.proto\":\n\x06Record\x12\x0b\n\x03key\x18\x01 \x01(\x0c\x12\r\n\x05value\x18\x02 \x01(\x0c\x12\x14\n\x0ctimeReceived\x18\x05 \x01(\t\"\xca\x03\n\x07Message\x12\"\n\x04type\x18\x01 \x01(\x0e\x32\x14.Message.MessageType\x12\x17\n\x0f\x63lusterLevelRaw\x18\n \x01(\x05\x12\x0b\n\x03key\x18\x02 \x01(\x0c\x12\x17\n\x06record\x18\x03 \x01(\x0b\x32\x07.Record\x12\"\n\x0b\x63loserPeers\x18\x08 \x03(\x0b\x32\r.Message.Peer\x12$\n\rproviderPeers\x18\t \x03(\x0b\x32\r.Message.Peer\x1aN\n\x04Peer\x12\n\n\x02id\x18\x01 \x01(\x0c\x12\r\n\x05\x61\x64\x64rs\x18\x02 \x03(\x0c\x12+\n\nconnection\x18\x03 \x01(\x0e\x32\x17.Message.ConnectionType\"i\n\x0bMessageType\x12\r\n\tPUT_VALUE\x10\x00\x12\r\n\tGET_VALUE\x10\x01\x12\x10\n\x0c\x41\x44\x44_PROVIDER\x10\x02\x12\x11\n\rGET_PROVIDERS\x10\x03\x12\r\n\tFIND_NODE\x10\x04\x12\x08\n\x04PING\x10\x05\"W\n\x0e\x43onnectionType\x12\x11\n\rNOT_CONNECTED\x10\x00\x12\r\n\tCONNECTED\x10\x01\x12\x0f\n\x0b\x43\x41N_CONNECT\x10\x02\x12\x12\n\x0e\x43\x41NNOT_CONNECT\x10\x03\x62\x06proto3')
 
-_globals = globals()
-_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
-_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.kad_dht.pb.kademlia_pb2', _globals)
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.kad_dht.pb.kademlia_pb2', globals())
 if _descriptor._USE_C_DESCRIPTORS == False:
+
   DESCRIPTOR._options = None
-  _globals['_RECORD']._serialized_start=36
-  _globals['_RECORD']._serialized_end=94
-  _globals['_MESSAGE']._serialized_start=97
-  _globals['_MESSAGE']._serialized_end=555
-  _globals['_MESSAGE_PEER']._serialized_start=281
-  _globals['_MESSAGE_PEER']._serialized_end=359
-  _globals['_MESSAGE_MESSAGETYPE']._serialized_start=361
-  _globals['_MESSAGE_MESSAGETYPE']._serialized_end=466
-  _globals['_MESSAGE_CONNECTIONTYPE']._serialized_start=468
-  _globals['_MESSAGE_CONNECTIONTYPE']._serialized_end=555
+  _RECORD._serialized_start=36
+  _RECORD._serialized_end=94
+  _MESSAGE._serialized_start=97
+  _MESSAGE._serialized_end=555
+  _MESSAGE_PEER._serialized_start=281
+  _MESSAGE_PEER._serialized_end=359
+  _MESSAGE_MESSAGETYPE._serialized_start=361
+  _MESSAGE_MESSAGETYPE._serialized_end=466
+  _MESSAGE_CONNECTIONTYPE._serialized_start=468
+  _MESSAGE_CONNECTIONTYPE._serialized_end=555
 # @@protoc_insertion_point(module_scope)

libp2p/kad_dht/routing_table.py

@@ -8,6 +8,7 @@ from collections import (
 import logging
 import time
 
+import multihash
 import trio
 
 from libp2p.abc import (
@@ -40,6 +41,22 @@ PEER_REFRESH_INTERVAL = 60  # Interval to refresh peers in seconds
 STALE_PEER_THRESHOLD = 3600  # Time in seconds after which a peer is considered stale
 
 
+def peer_id_to_key(peer_id: ID) -> bytes:
+    """
+    Convert a peer ID to a 256-bit key for routing table operations.
+    This normalizes all peer IDs to exactly 256 bits by hashing them with SHA-256.
+
+    :param peer_id: The peer ID to convert
+    :return: 32-byte (256-bit) key for routing table operations
+    """
+    return multihash.digest(peer_id.to_bytes(), "sha2-256").digest
+
+
+def key_to_int(key: bytes) -> int:
+    """Convert a 256-bit key to an integer for range calculations."""
+    return int.from_bytes(key, byteorder="big")
+
+
 class KBucket:
     """
     A k-bucket implementation for the Kademlia DHT.
@@ -357,9 +374,24 @@ class KBucket:
             True if the key is in range, False otherwise
 
         """
-        key_int = int.from_bytes(key, byteorder="big")
+        key_int = key_to_int(key)
         return self.min_range <= key_int < self.max_range
 
+    def peer_id_in_range(self, peer_id: ID) -> bool:
+        """
+        Check if a peer ID is in the range of this bucket.
+
+        params: peer_id: The peer ID to check
+
+        Returns
+        -------
+        bool
+            True if the peer ID is in range, False otherwise
+
+        """
+        key = peer_id_to_key(peer_id)
+        return self.key_in_range(key)
+
     def split(self) -> tuple["KBucket", "KBucket"]:
         """
         Split the bucket into two buckets.
@@ -376,8 +408,9 @@ class KBucket:
 
         # Redistribute peers
         for peer_id, (peer_info, timestamp) in self.peers.items():
-            peer_key = int.from_bytes(peer_id.to_bytes(), byteorder="big")
-            if peer_key < midpoint:
+            peer_key = peer_id_to_key(peer_id)
+            peer_key_int = key_to_int(peer_key)
+            if peer_key_int < midpoint:
                 lower_bucket.peers[peer_id] = (peer_info, timestamp)
             else:
                 upper_bucket.peers[peer_id] = (peer_info, timestamp)
@@ -458,7 +491,38 @@ class RoutingTable:
             success = await bucket.add_peer(peer_info)
             if success:
                 logger.debug(f"Successfully added peer {peer_id} to routing table")
-            return success
+                return True
+
+            # If bucket is full and couldn't add peer, try splitting the bucket
+            # Only split if the bucket contains our Peer ID
+            if self._should_split_bucket(bucket):
+                logger.debug(
+                    f"Bucket is full, attempting to split bucket for peer {peer_id}"
+                )
+                split_success = self._split_bucket(bucket)
+                if split_success:
+                    # After splitting,
+                    # find the appropriate bucket for the peer and try to add it
+                    target_bucket = self.find_bucket(peer_info.peer_id)
+                    success = await target_bucket.add_peer(peer_info)
+                    if success:
+                        logger.debug(
+                            f"Successfully added peer {peer_id} after bucket split"
+                        )
+                        return True
+                    else:
+                        logger.debug(
+                            f"Failed to add peer {peer_id} even after bucket split"
+                        )
+                        return False
+                else:
+                    logger.debug(f"Failed to split bucket for peer {peer_id}")
+                    return False
+            else:
+                logger.debug(
+                    f"Bucket is full and cannot be split, peer {peer_id} not added"
+                )
+                return False
 
         except Exception as e:
             logger.debug(f"Error adding peer {peer_obj} to routing table: {e}")
@@ -480,9 +544,9 @@ class RoutingTable:
 
     def find_bucket(self, peer_id: ID) -> KBucket:
         """
-        Find the bucket that would contain the given peer ID or PeerInfo.
+        Find the bucket that would contain the given peer ID.
 
-        :param peer_obj: Either a peer ID or a PeerInfo object
+        :param peer_id: The peer ID to find a bucket for
 
         Returns
         -------
@@ -490,7 +554,7 @@ class RoutingTable:
 
         """
         for bucket in self.buckets:
-            if bucket.key_in_range(peer_id.to_bytes()):
+            if bucket.peer_id_in_range(peer_id):
                 return bucket
 
         return self.buckets[0]
@@ -513,7 +577,11 @@ class RoutingTable:
             all_peers.extend(bucket.peer_ids())
 
         # Sort by XOR distance to the key
-        all_peers.sort(key=lambda p: xor_distance(p.to_bytes(), key))
+        def distance_to_key(peer_id: ID) -> int:
+            peer_key = peer_id_to_key(peer_id)
+            return xor_distance(peer_key, key)
+
+        all_peers.sort(key=distance_to_key)
 
         return all_peers[:count]
 
@@ -591,6 +659,20 @@ class RoutingTable:
             stale_peers.extend(bucket.get_stale_peers(stale_threshold_seconds))
         return stale_peers
 
+    def get_peer_infos(self) -> list[PeerInfo]:
+        """
+        Get all PeerInfo objects in the routing table.
+
+        Returns
+        -------
+            List[PeerInfo]: List of all PeerInfo objects
+
+        """
+        peer_infos = []
+        for bucket in self.buckets:
+            peer_infos.extend(bucket.peer_infos())
+        return peer_infos
+
     def cleanup_routing_table(self) -> None:
         """
         Cleanup the routing table by removing all data.
@@ -598,3 +680,66 @@ class RoutingTable:
         """
         self.buckets = [KBucket(self.host, BUCKET_SIZE)]
         logger.info("Routing table cleaned up, all data removed.")
+
+    def _should_split_bucket(self, bucket: KBucket) -> bool:
+        """
+        Check if a bucket should be split according to Kademlia rules.
+
+        :param bucket: The bucket to check
+        :return: True if the bucket should be split
+        """
+        # Check if we've exceeded maximum buckets
+        if len(self.buckets) >= MAXIMUM_BUCKETS:
+            logger.debug("Maximum number of buckets reached, cannot split")
+            return False
+
+        # Check if the bucket contains our local ID
+        local_key = peer_id_to_key(self.local_id)
+        local_key_int = key_to_int(local_key)
+        contains_local_id = bucket.min_range <= local_key_int < bucket.max_range
+
+        logger.debug(
+            f"Bucket range: {bucket.min_range} - {bucket.max_range}, "
+            f"local_key_int: {local_key_int}, contains_local: {contains_local_id}"
+        )
+
+        return contains_local_id
+
+    def _split_bucket(self, bucket: KBucket) -> bool:
+        """
+        Split a bucket into two buckets.
+
+        :param bucket: The bucket to split
+        :return: True if the bucket was successfully split
+        """
+        try:
+            # Find the bucket index
+            bucket_index = self.buckets.index(bucket)
+            logger.debug(f"Splitting bucket at index {bucket_index}")
+
+            # Split the bucket
+            lower_bucket, upper_bucket = bucket.split()
+
+            # Replace the original bucket with the two new buckets
+            self.buckets[bucket_index] = lower_bucket
+            self.buckets.insert(bucket_index + 1, upper_bucket)
+
+            logger.debug(
+                f"Bucket split successful. New bucket count: {len(self.buckets)}"
+            )
+            logger.debug(
+                f"Lower bucket range: "
+                f"{lower_bucket.min_range} - {lower_bucket.max_range}, "
+                f"peers: {lower_bucket.size()}"
+            )
+            logger.debug(
+                f"Upper bucket range: "
+                f"{upper_bucket.min_range} - {upper_bucket.max_range}, "
+                f"peers: {upper_bucket.size()}"
+            )
+
+            return True
+
+        except Exception as e:
+            logger.error(f"Error splitting bucket: {e}")
+            return False

libp2p/network/connection/swarm_connection.py

@@ -3,6 +3,7 @@ from typing import (
     TYPE_CHECKING,
 )
 
+from multiaddr import Multiaddr
 import trio
 
 from libp2p.abc import (
@@ -22,7 +23,8 @@ if TYPE_CHECKING:
 
 
 """
-Reference: https://github.com/libp2p/go-libp2p-swarm/blob/04c86bbdafd390651cb2ee14e334f7caeedad722/swarm_conn.go
+Reference: https://github.com/libp2p/go-libp2p-swarm/blob/
+04c86bbdafd390651cb2ee14e334f7caeedad722/swarm_conn.go
 """
 
 
@@ -42,6 +44,21 @@ class SwarmConn(INetConn):
         self.streams = set()
         self.event_closed = trio.Event()
         self.event_started = trio.Event()
+        # Provide back-references/hooks expected by NetStream
+        try:
+            setattr(self.muxed_conn, "swarm", self.swarm)
+
+            # NetStream expects an awaitable remove_stream hook
+            async def _remove_stream_hook(stream: NetStream) -> None:
+                self.remove_stream(stream)
+
+            setattr(self.muxed_conn, "remove_stream", _remove_stream_hook)
+        except Exception as e:
+            logging.warning(
+                f"Failed to set optional conveniences on muxed_conn "
+                f"for peer {muxed_conn.peer_id}: {e}"
+            )
+            # optional conveniences
         if hasattr(muxed_conn, "on_close"):
             logging.debug(f"Setting on_close for peer {muxed_conn.peer_id}")
             setattr(muxed_conn, "on_close", self._on_muxed_conn_closed)
@@ -147,6 +164,24 @@ class SwarmConn(INetConn):
     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/network/swarm.py

@@ -1,3 +1,7 @@
+from collections.abc import (
+    Awaitable,
+    Callable,
+)
 import logging
 
 from multiaddr import (
@@ -411,7 +415,15 @@ class Swarm(Service, INetworkService):
                 nursery.start_soon(notifee.listen, self, multiaddr)
 
     async def notify_closed_stream(self, stream: INetStream) -> None:
-        raise NotImplementedError
+        async with trio.open_nursery() as nursery:
+            for notifee in self.notifees:
+                nursery.start_soon(notifee.closed_stream, self, stream)
 
     async def notify_listen_close(self, multiaddr: Multiaddr) -> None:
         raise NotImplementedError
+
+    # Generic notifier used by NetStream._notify_closed
+    async def notify_all(self, notifier: Callable[[INotifee], Awaitable[None]]) -> None:
+        async with trio.open_nursery() as nursery:
+            for notifee in self.notifees:
+                nursery.start_soon(notifier, notifee)

libp2p/peer/envelope.py

@@ -0,0 +1,271 @@
+from typing import Any, cast
+
+from libp2p.crypto.ed25519 import Ed25519PublicKey
+from libp2p.crypto.keys import PrivateKey, PublicKey
+from libp2p.crypto.rsa import RSAPublicKey
+from libp2p.crypto.secp256k1 import Secp256k1PublicKey
+import libp2p.peer.pb.crypto_pb2 as cryto_pb
+import libp2p.peer.pb.envelope_pb2 as pb
+import libp2p.peer.pb.peer_record_pb2 as record_pb
+from libp2p.peer.peer_record import (
+    PeerRecord,
+    peer_record_from_protobuf,
+    unmarshal_record,
+)
+from libp2p.utils.varint import encode_uvarint
+
+ENVELOPE_DOMAIN = "libp2p-peer-record"
+PEER_RECORD_CODEC = b"\x03\x01"
+
+
+class Envelope:
+    """
+    A signed wrapper around a serialized libp2p record.
+
+    Envelopes are cryptographically signed by the author's private key
+    and are scoped to a specific 'domain' to prevent cross-protocol replay.
+
+    Attributes:
+        public_key: The public key that can verify the envelope's signature.
+        payload_type: A multicodec code identifying the type of payload inside.
+        raw_payload: The raw serialized record data.
+        signature: Signature over the domain-scoped payload content.
+
+    """
+
+    public_key: PublicKey
+    payload_type: bytes
+    raw_payload: bytes
+    signature: bytes
+
+    _cached_record: PeerRecord | None = None
+    _unmarshal_error: Exception | None = None
+
+    def __init__(
+        self,
+        public_key: PublicKey,
+        payload_type: bytes,
+        raw_payload: bytes,
+        signature: bytes,
+    ):
+        self.public_key = public_key
+        self.payload_type = payload_type
+        self.raw_payload = raw_payload
+        self.signature = signature
+
+    def marshal_envelope(self) -> bytes:
+        """
+        Serialize this Envelope into its protobuf wire format.
+
+        Converts all envelope fields into a `pb.Envelope` protobuf message
+        and returns the serialized bytes.
+
+        :return: Serialized envelope as bytes.
+        """
+        pb_env = pb.Envelope(
+            public_key=pub_key_to_protobuf(self.public_key),
+            payload_type=self.payload_type,
+            payload=self.raw_payload,
+            signature=self.signature,
+        )
+        return pb_env.SerializeToString()
+
+    def validate(self, domain: str) -> None:
+        """
+        Verify the envelope's signature within the given domain scope.
+
+        This ensures that the envelope has not been tampered with
+        and was signed under the correct usage context.
+
+        :param domain: Domain string that contextualizes the signature.
+        :raises ValueError: If the signature is invalid.
+        """
+        unsigned = make_unsigned(domain, self.payload_type, self.raw_payload)
+        if not self.public_key.verify(unsigned, self.signature):
+            raise ValueError("Invalid envelope signature")
+
+    def record(self) -> PeerRecord:
+        """
+        Lazily decode and return the embedded PeerRecord.
+
+        This method unmarshals the payload bytes into a `PeerRecord` instance,
+        using the registered codec to identify the type. The decoded result
+        is cached for future use.
+
+        :return: Decoded PeerRecord object.
+        :raises Exception: If decoding fails or payload type is unsupported.
+        """
+        if self._cached_record is not None:
+            return self._cached_record
+
+        try:
+            if self.payload_type != PEER_RECORD_CODEC:
+                raise ValueError("Unsuported payload type in envelope")
+            msg = record_pb.PeerRecord()
+            msg.ParseFromString(self.raw_payload)
+
+            self._cached_record = peer_record_from_protobuf(msg)
+            return self._cached_record
+        except Exception as e:
+            self._unmarshal_error = e
+            raise
+
+    def equal(self, other: Any) -> bool:
+        """
+        Compare this Envelope with another for structural equality.
+
+        Two envelopes are considered equal if:
+        - They have the same public key
+        - The payload type and payload bytes match
+        - Their signatures are identical
+
+        :param other: Another object to compare.
+        :return: True if equal, False otherwise.
+        """
+        if isinstance(other, Envelope):
+            return (
+                self.public_key.__eq__(other.public_key)
+                and self.payload_type == other.payload_type
+                and self.signature == other.signature
+                and self.raw_payload == other.raw_payload
+            )
+        return False
+
+
+def pub_key_to_protobuf(pub_key: PublicKey) -> cryto_pb.PublicKey:
+    """
+    Convert a Python PublicKey object to its protobuf equivalent.
+
+    :param pub_key: A libp2p-compatible PublicKey instance.
+    :return: Serialized protobuf PublicKey message.
+    """
+    internal_key_type = pub_key.get_type()
+    key_type = cast(cryto_pb.KeyType, internal_key_type.value)
+    data = pub_key.to_bytes()
+    protobuf_key = cryto_pb.PublicKey(Type=key_type, Data=data)
+    return protobuf_key
+
+
+def pub_key_from_protobuf(pb_key: cryto_pb.PublicKey) -> PublicKey:
+    """
+    Parse a protobuf PublicKey message into a native libp2p PublicKey.
+
+    Supports Ed25519, RSA, and Secp256k1 key types.
+
+    :param pb_key: Protobuf representation of a public key.
+    :return: Parsed PublicKey object.
+    :raises ValueError: If the key type is unrecognized.
+    """
+    if pb_key.Type == cryto_pb.KeyType.Ed25519:
+        return Ed25519PublicKey.from_bytes(pb_key.Data)
+    elif pb_key.Type == cryto_pb.KeyType.RSA:
+        return RSAPublicKey.from_bytes(pb_key.Data)
+    elif pb_key.Type == cryto_pb.KeyType.Secp256k1:
+        return Secp256k1PublicKey.from_bytes(pb_key.Data)
+    # libp2p.crypto.ecdsa not implemented
+    else:
+        raise ValueError(f"Unknown key type: {pb_key.Type}")
+
+
+def seal_record(record: PeerRecord, private_key: PrivateKey) -> Envelope:
+    """
+    Create and sign a new Envelope from a PeerRecord.
+
+    The record is serialized and signed in the scope of its domain and codec.
+    The result is a self-contained, verifiable Envelope.
+
+    :param record: A PeerRecord to encapsulate.
+    :param private_key: The signer's private key.
+    :return: A signed Envelope instance.
+    """
+    payload = record.marshal_record()
+
+    unsigned = make_unsigned(record.domain(), record.codec(), payload)
+    signature = private_key.sign(unsigned)
+
+    return Envelope(
+        public_key=private_key.get_public_key(),
+        payload_type=record.codec(),
+        raw_payload=payload,
+        signature=signature,
+    )
+
+
+def consume_envelope(data: bytes, domain: str) -> tuple[Envelope, PeerRecord]:
+    """
+    Parse, validate, and decode an Envelope from bytes.
+
+    Validates the envelope's signature using the given domain and decodes
+    the inner payload into a PeerRecord.
+
+    :param data: Serialized envelope bytes.
+    :param domain: Domain string to verify signature against.
+    :return: Tuple of (Envelope, PeerRecord).
+    :raises ValueError: If signature validation or decoding fails.
+    """
+    env = unmarshal_envelope(data)
+    env.validate(domain)
+    record = env.record()
+    return env, record
+
+
+def unmarshal_envelope(data: bytes) -> Envelope:
+    """
+    Deserialize an Envelope from its wire format.
+
+    This parses the protobuf fields without verifying the signature.
+
+    :param data: Serialized envelope bytes.
+    :return: Parsed Envelope object.
+    :raises DecodeError: If protobuf parsing fails.
+    """
+    pb_env = pb.Envelope()
+    pb_env.ParseFromString(data)
+    pk = pub_key_from_protobuf(pb_env.public_key)
+
+    return Envelope(
+        public_key=pk,
+        payload_type=pb_env.payload_type,
+        raw_payload=pb_env.payload,
+        signature=pb_env.signature,
+    )
+
+
+def make_unsigned(domain: str, payload_type: bytes, payload: bytes) -> bytes:
+    """
+    Build a byte buffer to be signed for an Envelope.
+
+    The unsigned byte structure is:
+        varint(len(domain)) || domain ||
+        varint(len(payload_type)) || payload_type ||
+        varint(len(payload)) || payload
+
+    This is the exact input used during signing and verification.
+
+    :param domain: Domain string for signature scoping.
+    :param payload_type: Identifier for the type of payload.
+    :param payload: Raw serialized payload bytes.
+    :return: Byte buffer to be signed or verified.
+    """
+    fields = [domain.encode(), payload_type, payload]
+    buf = bytearray()
+
+    for field in fields:
+        buf.extend(encode_uvarint(len(field)))
+        buf.extend(field)
+
+    return bytes(buf)
+
+
+def debug_dump_envelope(env: Envelope) -> None:
+    print("\n=== Envelope ===")
+    print(f"Payload Type: {env.payload_type!r}")
+    print(f"Signature: {env.signature.hex()} ({len(env.signature)} bytes)")
+    print(f"Raw Payload: {env.raw_payload.hex()} ({len(env.raw_payload)} bytes)")
+
+    try:
+        peer_record = unmarshal_record(env.raw_payload)
+        print("\n=== Parsed PeerRecord ===")
+        print(peer_record)
+    except Exception as e:
+        print("Failed to parse PeerRecord:", e)

libp2p/peer/id.py

@@ -1,3 +1,4 @@
+import functools
 import hashlib
 
 import base58
@@ -36,25 +37,23 @@ if ENABLE_INLINING:
 
 class ID:
     _bytes: bytes
-    _xor_id: int | None = None
-    _b58_str: str | None = None
 
     def __init__(self, peer_id_bytes: bytes) -> None:
         self._bytes = peer_id_bytes
 
-    @property
+    @functools.cached_property
     def xor_id(self) -> int:
-        if not self._xor_id:
-            self._xor_id = int(sha256_digest(self._bytes).hex(), 16)
-        return self._xor_id
+        return int(sha256_digest(self._bytes).hex(), 16)
+
+    @functools.cached_property
+    def base58(self) -> str:
+        return base58.b58encode(self._bytes).decode()
 
     def to_bytes(self) -> bytes:
         return self._bytes
 
     def to_base58(self) -> str:
-        if not self._b58_str:
-            self._b58_str = base58.b58encode(self._bytes).decode()
-        return self._b58_str
+        return self.base58
 
     def __repr__(self) -> str:
         return f"<libp2p.peer.id.ID ({self!s})>"

libp2p/peer/pb/crypto.proto

@@ -0,0 +1,22 @@
+syntax = "proto3";
+
+package libp2p.peer.pb.crypto;
+
+option go_package = "github.com/libp2p/go-libp2p/core/crypto/pb";
+
+enum KeyType {
+    RSA = 0;
+    Ed25519 = 1;
+    Secp256k1 = 2;
+    ECDSA = 3;
+}
+
+message PublicKey {
+    KeyType Type = 1;
+    bytes Data = 2;
+}
+
+message PrivateKey {
+    KeyType Type = 1;
+    bytes Data = 2;
+}

libp2p/peer/pb/crypto_pb2.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: libp2p/peer/pb/crypto.proto
+# Protobuf Python Version: 4.25.3
+"""Generated protocol buffer code."""
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import descriptor_pool as _descriptor_pool
+from google.protobuf import symbol_database as _symbol_database
+from google.protobuf.internal import builder as _builder
+# @@protoc_insertion_point(imports)
+
+_sym_db = _symbol_database.Default()
+
+
+
+
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1blibp2p/peer/pb/crypto.proto\x12\x15libp2p.peer.pb.crypto\"G\n\tPublicKey\x12,\n\x04Type\x18\x01 \x01(\x0e\x32\x1e.libp2p.peer.pb.crypto.KeyType\x12\x0c\n\x04\x44\x61ta\x18\x02 \x01(\x0c\"H\n\nPrivateKey\x12,\n\x04Type\x18\x01 \x01(\x0e\x32\x1e.libp2p.peer.pb.crypto.KeyType\x12\x0c\n\x04\x44\x61ta\x18\x02 \x01(\x0c*9\n\x07KeyType\x12\x07\n\x03RSA\x10\x00\x12\x0b\n\x07\x45\x64\x32\x35\x35\x31\x39\x10\x01\x12\r\n\tSecp256k1\x10\x02\x12\t\n\x05\x45\x43\x44SA\x10\x03\x42,Z*github.com/libp2p/go-libp2p/core/crypto/pbb\x06proto3')
+
+_globals = globals()
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.peer.pb.crypto_pb2', _globals)
+if _descriptor._USE_C_DESCRIPTORS == False:
+  _globals['DESCRIPTOR']._options = None
+  _globals['DESCRIPTOR']._serialized_options = b'Z*github.com/libp2p/go-libp2p/core/crypto/pb'
+  _globals['_KEYTYPE']._serialized_start=201
+  _globals['_KEYTYPE']._serialized_end=258
+  _globals['_PUBLICKEY']._serialized_start=54
+  _globals['_PUBLICKEY']._serialized_end=125
+  _globals['_PRIVATEKEY']._serialized_start=127
+  _globals['_PRIVATEKEY']._serialized_end=199
+# @@protoc_insertion_point(module_scope)

libp2p/peer/pb/crypto_pb2.pyi

@@ -0,0 +1,33 @@
+from google.protobuf.internal import enum_type_wrapper as _enum_type_wrapper
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from typing import ClassVar as _ClassVar, Optional as _Optional, Union as _Union
+
+DESCRIPTOR: _descriptor.FileDescriptor
+
+class KeyType(int, metaclass=_enum_type_wrapper.EnumTypeWrapper):
+    __slots__ = ()
+    RSA: _ClassVar[KeyType]
+    Ed25519: _ClassVar[KeyType]
+    Secp256k1: _ClassVar[KeyType]
+    ECDSA: _ClassVar[KeyType]
+RSA: KeyType
+Ed25519: KeyType
+Secp256k1: KeyType
+ECDSA: KeyType
+
+class PublicKey(_message.Message):
+    __slots__ = ("Type", "Data")
+    TYPE_FIELD_NUMBER: _ClassVar[int]
+    DATA_FIELD_NUMBER: _ClassVar[int]
+    Type: KeyType
+    Data: bytes
+    def __init__(self, Type: _Optional[_Union[KeyType, str]] = ..., Data: _Optional[bytes] = ...) -> None: ...
+
+class PrivateKey(_message.Message):
+    __slots__ = ("Type", "Data")
+    TYPE_FIELD_NUMBER: _ClassVar[int]
+    DATA_FIELD_NUMBER: _ClassVar[int]
+    Type: KeyType
+    Data: bytes
+    def __init__(self, Type: _Optional[_Union[KeyType, str]] = ..., Data: _Optional[bytes] = ...) -> None: ...

libp2p/peer/pb/envelope.proto

@@ -0,0 +1,14 @@
+syntax = "proto3";
+
+package libp2p.peer.pb.record;
+
+import "libp2p/peer/pb/crypto.proto";
+
+option go_package = "github.com/libp2p/go-libp2p/core/record/pb";
+
+message Envelope {
+    libp2p.peer.pb.crypto.PublicKey public_key = 1;
+    bytes payload_type = 2;
+    bytes payload = 3;
+    bytes signature = 5;
+}

libp2p/peer/pb/envelope_pb2.py

@@ -0,0 +1,28 @@
+# -*- coding: utf-8 -*-
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: libp2p/peer/pb/envelope.proto
+# Protobuf Python Version: 4.25.3
+"""Generated protocol buffer code."""
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import descriptor_pool as _descriptor_pool
+from google.protobuf import symbol_database as _symbol_database
+from google.protobuf.internal import builder as _builder
+# @@protoc_insertion_point(imports)
+
+_sym_db = _symbol_database.Default()
+
+
+from libp2p.peer.pb import crypto_pb2 as libp2p_dot_peer_dot_pb_dot_crypto__pb2
+
+
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1dlibp2p/peer/pb/envelope.proto\x12\x15libp2p.peer.pb.record\x1a\x1blibp2p/peer/pb/crypto.proto\"z\n\x08\x45nvelope\x12\x34\n\npublic_key\x18\x01 \x01(\x0b\x32 .libp2p.peer.pb.crypto.PublicKey\x12\x14\n\x0cpayload_type\x18\x02 \x01(\x0c\x12\x0f\n\x07payload\x18\x03 \x01(\x0c\x12\x11\n\tsignature\x18\x05 \x01(\x0c\x42,Z*github.com/libp2p/go-libp2p/core/record/pbb\x06proto3')
+
+_globals = globals()
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.peer.pb.envelope_pb2', _globals)
+if _descriptor._USE_C_DESCRIPTORS == False:
+  _globals['DESCRIPTOR']._options = None
+  _globals['DESCRIPTOR']._serialized_options = b'Z*github.com/libp2p/go-libp2p/core/record/pb'
+  _globals['_ENVELOPE']._serialized_start=85
+  _globals['_ENVELOPE']._serialized_end=207
+# @@protoc_insertion_point(module_scope)

libp2p/peer/pb/envelope_pb2.pyi

@@ -0,0 +1,18 @@
+from libp2p.peer.pb import crypto_pb2 as _crypto_pb2
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from typing import ClassVar as _ClassVar, Mapping as _Mapping, Optional as _Optional, Union as _Union
+
+DESCRIPTOR: _descriptor.FileDescriptor
+
+class Envelope(_message.Message):
+    __slots__ = ("public_key", "payload_type", "payload", "signature")
+    PUBLIC_KEY_FIELD_NUMBER: _ClassVar[int]
+    PAYLOAD_TYPE_FIELD_NUMBER: _ClassVar[int]
+    PAYLOAD_FIELD_NUMBER: _ClassVar[int]
+    SIGNATURE_FIELD_NUMBER: _ClassVar[int]
+    public_key: _crypto_pb2.PublicKey
+    payload_type: bytes
+    payload: bytes
+    signature: bytes
+    def __init__(self, public_key: _Optional[_Union[_crypto_pb2.PublicKey, _Mapping]] = ..., payload_type: _Optional[bytes] = ..., payload: _Optional[bytes] = ..., signature: _Optional[bytes] = ...) -> None: ... # type: ignore[type-arg]

libp2p/peer/pb/peer_record.proto

@@ -0,0 +1,31 @@
+syntax = "proto3";
+
+package peer.pb;
+
+option go_package = "github.com/libp2p/go-libp2p/core/peer/pb";
+
+// PeerRecord messages contain information that is useful to share with other peers.
+// Currently, a PeerRecord contains the public listen addresses for a peer, but this
+// is expected to expand to include other information in the future.
+//
+// PeerRecords are designed to be serialized to bytes and placed inside of
+// SignedEnvelopes before sharing with other peers.
+// See https://github.com/libp2p/go-libp2p/blob/master/core/record/pb/envelope.proto for
+// the SignedEnvelope definition.
+message PeerRecord {
+
+    // AddressInfo is a wrapper around a binary multiaddr. It is defined as a
+    // separate message to allow us to add per-address metadata in the future.
+    message AddressInfo {
+        bytes multiaddr = 1;
+    }
+
+    // peer_id contains a libp2p peer id in its binary representation.
+    bytes peer_id = 1;
+
+    // seq contains a monotonically-increasing sequence counter to order PeerRecords in time.
+    uint64 seq = 2;
+
+    // addresses is a list of public listen addresses for the peer.
+    repeated AddressInfo addresses = 3;
+}

libp2p/peer/pb/peer_record_pb2.py

@@ -0,0 +1,29 @@
+# -*- coding: utf-8 -*-
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: libp2p/peer/pb/peer_record.proto
+# Protobuf Python Version: 4.25.3
+"""Generated protocol buffer code."""
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import descriptor_pool as _descriptor_pool
+from google.protobuf import symbol_database as _symbol_database
+from google.protobuf.internal import builder as _builder
+# @@protoc_insertion_point(imports)
+
+_sym_db = _symbol_database.Default()
+
+
+
+
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n libp2p/peer/pb/peer_record.proto\x12\x07peer.pb\"\x80\x01\n\nPeerRecord\x12\x0f\n\x07peer_id\x18\x01 \x01(\x0c\x12\x0b\n\x03seq\x18\x02 \x01(\x04\x12\x32\n\taddresses\x18\x03 \x03(\x0b\x32\x1f.peer.pb.PeerRecord.AddressInfo\x1a \n\x0b\x41\x64\x64ressInfo\x12\x11\n\tmultiaddr\x18\x01 \x01(\x0c\x42*Z(github.com/libp2p/go-libp2p/core/peer/pbb\x06proto3')
+
+_globals = globals()
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.peer.pb.peer_record_pb2', _globals)
+if _descriptor._USE_C_DESCRIPTORS == False:
+  _globals['DESCRIPTOR']._options = None
+  _globals['DESCRIPTOR']._serialized_options = b'Z(github.com/libp2p/go-libp2p/core/peer/pb'
+  _globals['_PEERRECORD']._serialized_start=46
+  _globals['_PEERRECORD']._serialized_end=174
+  _globals['_PEERRECORD_ADDRESSINFO']._serialized_start=142
+  _globals['_PEERRECORD_ADDRESSINFO']._serialized_end=174
+# @@protoc_insertion_point(module_scope)

libp2p/peer/pb/peer_record_pb2.pyi

@@ -0,0 +1,21 @@
+from google.protobuf.internal import containers as _containers
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from typing import ClassVar as _ClassVar, Iterable as _Iterable, Mapping as _Mapping, Optional as _Optional, Union as _Union
+
+DESCRIPTOR: _descriptor.FileDescriptor
+
+class PeerRecord(_message.Message):
+    __slots__ = ("peer_id", "seq", "addresses")
+    class AddressInfo(_message.Message):
+        __slots__ = ("multiaddr",)
+        MULTIADDR_FIELD_NUMBER: _ClassVar[int]
+        multiaddr: bytes
+        def __init__(self, multiaddr: _Optional[bytes] = ...) -> None: ...
+    PEER_ID_FIELD_NUMBER: _ClassVar[int]
+    SEQ_FIELD_NUMBER: _ClassVar[int]
+    ADDRESSES_FIELD_NUMBER: _ClassVar[int]
+    peer_id: bytes
+    seq: int
+    addresses: _containers.RepeatedCompositeFieldContainer[PeerRecord.AddressInfo]
+    def __init__(self, peer_id: _Optional[bytes] = ..., seq: _Optional[int] = ..., addresses: _Optional[_Iterable[_Union[PeerRecord.AddressInfo, _Mapping]]] = ...) -> None: ...    # type: ignore[type-arg]

libp2p/peer/peer_record.py

@@ -0,0 +1,251 @@
+from collections.abc import Sequence
+import threading
+import time
+from typing import Any
+
+from multiaddr import Multiaddr
+
+from libp2p.abc import IPeerRecord
+from libp2p.peer.id import ID
+import libp2p.peer.pb.peer_record_pb2 as pb
+from libp2p.peer.peerinfo import PeerInfo
+
+PEER_RECORD_ENVELOPE_DOMAIN = "libp2p-peer-record"
+PEER_RECORD_ENVELOPE_PAYLOAD_TYPE = b"\x03\x01"
+
+_last_timestamp_lock = threading.Lock()
+_last_timestamp: int = 0
+
+
+class PeerRecord(IPeerRecord):
+    """
+    A record that contains metatdata about a peer in the libp2p network.
+
+    This includes:
+    - `peer_id`: The peer's globally unique indentifier.
+    - `addrs`: A list of the peer's publicly reachable multiaddrs.
+    - `seq`: A strictly monotonically increasing timestamp used
+            to order records over time.
+
+    PeerRecords are designed to be signed and transmitted in libp2p routing Envelopes.
+    """
+
+    peer_id: ID
+    addrs: list[Multiaddr]
+    seq: int
+
+    def __init__(
+        self,
+        peer_id: ID | None = None,
+        addrs: list[Multiaddr] | None = None,
+        seq: int | None = None,
+    ) -> None:
+        """
+        Initialize a new PeerRecord.
+        If `seq` is not provided, a timestamp-based strictly increasing sequence
+        number will be generated.
+
+        :param peer_id: ID of the peer this record refers to.
+        :param addrs: Public multiaddrs of the peer.
+        :param seq: Monotonic sequence number.
+
+        """
+        if peer_id is not None:
+            self.peer_id = peer_id
+        self.addrs = addrs or []
+        if seq is not None:
+            self.seq = seq
+        else:
+            self.seq = timestamp_seq()
+
+    def __repr__(self) -> str:
+        return (
+            f"PeerRecord(\n"
+            f"  peer_id={self.peer_id},\n"
+            f"  multiaddrs={[str(m) for m in self.addrs]},\n"
+            f"  seq={self.seq}\n"
+            f")"
+        )
+
+    def domain(self) -> str:
+        """
+        Return the domain string associated with this PeerRecord.
+
+        Used during record signing and envelope validation to identify the record type.
+        """
+        return PEER_RECORD_ENVELOPE_DOMAIN
+
+    def codec(self) -> bytes:
+        """
+        Return the codec identifier for PeerRecords.
+
+        This binary perfix helps distinguish PeerRecords in serialized envelopes.
+        """
+        return PEER_RECORD_ENVELOPE_PAYLOAD_TYPE
+
+    def to_protobuf(self) -> pb.PeerRecord:
+        """
+        Convert the current PeerRecord into a ProtoBuf PeerRecord message.
+
+        :raises ValueError: if peer_id serialization fails.
+        :return: A ProtoBuf-encoded PeerRecord message object.
+        """
+        try:
+            id_bytes = self.peer_id.to_bytes()
+        except Exception as e:
+            raise ValueError(f"failed to marshal peer_id: {e}")
+
+        msg = pb.PeerRecord()
+        msg.peer_id = id_bytes
+        msg.seq = self.seq
+        msg.addresses.extend(addrs_to_protobuf(self.addrs))
+        return msg
+
+    def marshal_record(self) -> bytes:
+        """
+        Serialize a PeerRecord into raw bytes suitable for embedding in an Envelope.
+
+        This is typically called during the process of signing or sealing the record.
+        :raises ValueError: if serialization to protobuf fails.
+        :return: Serialized PeerRecord bytes.
+        """
+        try:
+            msg = self.to_protobuf()
+            return msg.SerializeToString()
+        except Exception as e:
+            raise ValueError(f"failed to marshal PeerRecord: {e}")
+
+    def equal(self, other: Any) -> bool:
+        """
+        Check if this PeerRecord is identical to another.
+
+        Two PeerRecords are considered equal if:
+        - Their peer IDs match.
+        - Their sequence numbers are identical.
+        - Their address lists are identical and in the same order.
+
+        :param other: Another PeerRecord instance.
+        :return: True if all fields mathch, False otherwise.
+        """
+        if isinstance(other, PeerRecord):
+            if self.peer_id == other.peer_id:
+                if self.seq == other.seq:
+                    if len(self.addrs) == len(other.addrs):
+                        for a1, a2 in zip(self.addrs, other.addrs):
+                            if a1 == a2:
+                                continue
+                            else:
+                                return False
+                        return True
+        return False
+
+
+def unmarshal_record(data: bytes) -> PeerRecord:
+    """
+    Deserialize a PeerRecord from its serialized byte representation.
+
+    Typically used when receiveing a PeerRecord inside a signed routing Envelope.
+
+    :param data: Serialized protobuf-encoded bytes.
+    :raises ValueError: if parsing or conversion fails.
+    :reurn: A valid PeerRecord instance.
+    """
+    if data is None:
+        raise ValueError("cannot unmarshal PeerRecord from None")
+
+    msg = pb.PeerRecord()
+    try:
+        msg.ParseFromString(data)
+    except Exception as e:
+        raise ValueError(f"Failed to parse PeerRecord protobuf: {e}")
+
+    try:
+        record = peer_record_from_protobuf(msg)
+    except Exception as e:
+        raise ValueError(f"Failed to convert protobuf to PeerRecord: {e}")
+
+    return record
+
+
+def timestamp_seq() -> int:
+    """
+    Generate a strictly increasing timestamp-based sequence number.
+
+    Ensures that even if multiple PeerRecords are generated in the same nanosecond,
+    their `seq` values will still be strictly increasing by using a lock to track the
+    last value.
+
+    :return: A strictly increasing integer timestamp.
+    """
+    global _last_timestamp
+    now = int(time.time_ns())
+    with _last_timestamp_lock:
+        if now <= _last_timestamp:
+            now = _last_timestamp + 1
+        _last_timestamp = now
+    return now
+
+
+def peer_record_from_peer_info(info: PeerInfo) -> PeerRecord:
+    """
+    Create a PeerRecord from a PeerInfo object.
+
+    This automatically assigns a timestamp-based sequence number to the record.
+    :param info: A PeerInfo instance (contains peer_id and addrs).
+    :return: A PeerRecord instance.
+    """
+    record = PeerRecord()
+    record.peer_id = info.peer_id
+    record.addrs = info.addrs
+    return record
+
+
+def peer_record_from_protobuf(msg: pb.PeerRecord) -> PeerRecord:
+    """
+    Convert a protobuf PeerRecord message into a PeerRecord object.
+
+    :param msg: Protobuf PeerRecord message.
+    :raises ValueError: if the peer_id cannot be parsed.
+    :return: A deserialized PeerRecord instance.
+    """
+    try:
+        peer_id = ID(msg.peer_id)
+    except Exception as e:
+        raise ValueError(f"Failed to unmarshal peer_id: {e}")
+
+    addrs = addrs_from_protobuf(msg.addresses)
+    seq = msg.seq
+
+    return PeerRecord(peer_id, addrs, seq)
+
+
+def addrs_from_protobuf(addrs: Sequence[pb.PeerRecord.AddressInfo]) -> list[Multiaddr]:
+    """
+    Convert a list of protobuf address records to Multiaddr objects.
+
+    :param addrs: A list of protobuf PeerRecord.AddressInfo messages.
+    :return: A list of decoded Multiaddr instances (invalid ones are skipped).
+    """
+    out = []
+    for addr_info in addrs:
+        try:
+            addr = Multiaddr(addr_info.multiaddr)
+            out.append(addr)
+        except Exception:
+            continue
+    return out
+
+
+def addrs_to_protobuf(addrs: list[Multiaddr]) -> list[pb.PeerRecord.AddressInfo]:
+    """
+    Convert a list of Multiaddr objects into their protobuf representation.
+
+    :param addrs: A list of Multiaddr instances.
+    :return: A list of PeerRecord.AddressInfo protobuf messages.
+    """
+    out = []
+    for addr in addrs:
+        addr_info = pb.PeerRecord.AddressInfo()
+        addr_info.multiaddr = addr.to_bytes()
+        out.append(addr_info)
+    return out

libp2p/peer/peerdata.py

@@ -18,6 +18,13 @@ from libp2p.crypto.keys import (
     PublicKey,
 )
 
+"""
+Latency EWMA Smoothing governs the deacy of the EWMA (the speed at which
+is changes). This must be a normalized (0-1) value.
+1 is 100% change, 0 is no change.
+"""
+LATENCY_EWMA_SMOOTHING = 0.1
+
 
 class PeerData(IPeerData):
     pubkey: PublicKey | None
@@ -27,6 +34,7 @@ class PeerData(IPeerData):
     addrs: list[Multiaddr]
     last_identified: int
     ttl: int  # Keep ttl=0 by default for always valid
+    latmap: float
 
     def __init__(self) -> None:
         self.pubkey = None
@@ -36,6 +44,9 @@ class PeerData(IPeerData):
         self.addrs = []
         self.last_identified = int(time.time())
         self.ttl = 0
+        self.latmap = 0
+
+    # --------PROTO-BOOK--------
 
     def get_protocols(self) -> list[str]:
         """
@@ -55,6 +66,37 @@ class PeerData(IPeerData):
         """
         self.protocols = list(protocols)
 
+    def remove_protocols(self, protocols: Sequence[str]) -> None:
+        """
+        :param protocols: protocols to remove
+        """
+        for protocol in protocols:
+            if protocol in self.protocols:
+                self.protocols.remove(protocol)
+
+    def supports_protocols(self, protocols: Sequence[str]) -> list[str]:
+        """
+        :param protocols: protocols to check from
+        :return: all supported protocols in the given list
+        """
+        return [proto for proto in protocols if proto in self.protocols]
+
+    def first_supported_protocol(self, protocols: Sequence[str]) -> str:
+        """
+        :param protocols: protocols to check from
+        :return: first supported protocol in the given list
+        """
+        for protocol in protocols:
+            if protocol in self.protocols:
+                return protocol
+
+        return "None supported"
+
+    def clear_protocol_data(self) -> None:
+        """Clear all protocols"""
+        self.protocols = []
+
+    # -------ADDR-BOOK---------
     def add_addrs(self, addrs: Sequence[Multiaddr]) -> None:
         """
         :param addrs: multiaddresses to add
@@ -73,6 +115,7 @@ class PeerData(IPeerData):
         """Clear all addresses."""
         self.addrs = []
 
+    # -------METADATA-----------
     def put_metadata(self, key: str, val: Any) -> None:
         """
         :param key: key in KV pair
@@ -90,6 +133,11 @@ class PeerData(IPeerData):
             return self.metadata[key]
         raise PeerDataError("key not found")
 
+    def clear_metadata(self) -> None:
+        """Clears metadata."""
+        self.metadata = {}
+
+    # -------KEY-BOOK---------------
     def add_pubkey(self, pubkey: PublicKey) -> None:
         """
         :param pubkey:
@@ -120,9 +168,41 @@ class PeerData(IPeerData):
             raise PeerDataError("private key not found")
         return self.privkey
 
+    def clear_keydata(self) -> None:
+        """Clears keydata"""
+        self.pubkey = None
+        self.privkey = None
+
+    # ----------METRICS--------------
+    def record_latency(self, new_latency: float) -> None:
+        """
+        Records a new latency measurement for the given peer
+        using Exponentially Weighted Moving Average (EWMA)
+        :param new_latency: the new latency value
+        """
+        s = LATENCY_EWMA_SMOOTHING
+        if s > 1 or s < 0:
+            s = 0.1
+
+        if self.latmap == 0:
+            self.latmap = new_latency
+        else:
+            prev = self.latmap
+            updated = ((1.0 - s) * prev) + (s * new_latency)
+            self.latmap = updated
+
+    def latency_EWMA(self) -> float:
+        """Returns the latency EWMA value"""
+        return self.latmap
+
+    def clear_metrics(self) -> None:
+        """Clear the latency metrics"""
+        self.latmap = 0
+
     def update_last_identified(self) -> None:
         self.last_identified = int(time.time())
 
+    # ----------TTL------------------
     def get_last_identified(self) -> int:
         """
         :return: last identified timestamp

libp2p/peer/peerinfo.py

@@ -3,9 +3,11 @@ from collections.abc import (
 )
 from typing import (
     Any,
+    cast,
 )
 
 import multiaddr
+from multiaddr.protocols import Protocol
 
 from .id import (
     ID,
@@ -42,7 +44,8 @@ def info_from_p2p_addr(addr: multiaddr.Multiaddr) -> PeerInfo:
     p2p_protocols = p2p_part.protocols()
     if not p2p_protocols:
         raise InvalidAddrError("The last part of the address has no protocols")
-    last_protocol = p2p_protocols[0]
+    last_protocol = cast(Protocol, p2p_part.protocols()[0])
+
     if last_protocol is None:
         raise InvalidAddrError("The last protocol is None")
 

libp2p/peer/peerstore.py

@@ -2,6 +2,7 @@ from collections import (
     defaultdict,
 )
 from collections.abc import (
+    AsyncIterable,
     Sequence,
 )
 from typing import (
@@ -11,6 +12,8 @@ from typing import (
 from multiaddr import (
     Multiaddr,
 )
+import trio
+from trio import MemoryReceiveChannel, MemorySendChannel
 
 from libp2p.abc import (
     IPeerStore,
@@ -20,6 +23,7 @@ from libp2p.crypto.keys import (
     PrivateKey,
     PublicKey,
 )
+from libp2p.peer.envelope import Envelope
 
 from .id import (
     ID,
@@ -35,11 +39,23 @@ from .peerinfo import (
 PERMANENT_ADDR_TTL = 0
 
 
+class PeerRecordState:
+    envelope: Envelope
+    seq: int
+
+    def __init__(self, envelope: Envelope, seq: int):
+        self.envelope = envelope
+        self.seq = seq
+
+
 class PeerStore(IPeerStore):
     peer_data_map: dict[ID, PeerData]
 
-    def __init__(self) -> None:
+    def __init__(self, max_records: int = 10000) -> None:
         self.peer_data_map = defaultdict(PeerData)
+        self.addr_update_channels: dict[ID, MemorySendChannel[Multiaddr]] = {}
+        self.peer_record_map: dict[ID, PeerRecordState] = {}
+        self.max_records = max_records
 
     def peer_info(self, peer_id: ID) -> PeerInfo:
         """
@@ -53,6 +69,69 @@ class PeerStore(IPeerStore):
             return PeerInfo(peer_id, peer_data.get_addrs())
         raise PeerStoreError("peer ID not found")
 
+    def peer_ids(self) -> list[ID]:
+        """
+        :return: all of the peer IDs stored in peer store
+        """
+        return list(self.peer_data_map.keys())
+
+    def clear_peerdata(self, peer_id: ID) -> None:
+        """Clears all data associated with the given peer_id."""
+        if peer_id in self.peer_data_map:
+            del self.peer_data_map[peer_id]
+        else:
+            raise PeerStoreError("peer ID not found")
+
+        # Clear the peer records
+        if peer_id in self.peer_record_map:
+            self.peer_record_map.pop(peer_id, None)
+
+    def valid_peer_ids(self) -> list[ID]:
+        """
+        :return: all of the valid peer IDs stored in peer store
+        """
+        valid_peer_ids: list[ID] = []
+        for peer_id, peer_data in self.peer_data_map.items():
+            if not peer_data.is_expired():
+                valid_peer_ids.append(peer_id)
+            else:
+                peer_data.clear_addrs()
+        return valid_peer_ids
+
+    def _enforce_record_limit(self) -> None:
+        """Enforce maximum number of stored records."""
+        if len(self.peer_record_map) > self.max_records:
+            # Record oldest records based on seequence number
+            sorted_records = sorted(
+                self.peer_record_map.items(), key=lambda x: x[1].seq
+            )
+            records_to_remove = len(self.peer_record_map) - self.max_records
+            for peer_id, _ in sorted_records[:records_to_remove]:
+                self.maybe_delete_peer_record(peer_id)
+                del self.peer_record_map[peer_id]
+
+    async def start_cleanup_task(self, cleanup_interval: int = 3600) -> None:
+        """Start periodic cleanup of expired peer records and addresses."""
+        while True:
+            await trio.sleep(cleanup_interval)
+            self._cleanup_expired_records()
+
+    def _cleanup_expired_records(self) -> None:
+        """Remove expired peer records and addresses"""
+        expired_peers = []
+
+        for peer_id, peer_data in self.peer_data_map.items():
+            if peer_data.is_expired():
+                expired_peers.append(peer_id)
+
+        for peer_id in expired_peers:
+            self.maybe_delete_peer_record(peer_id)
+            del self.peer_data_map[peer_id]
+
+        self._enforce_record_limit()
+
+    # --------PROTO-BOOK--------
+
     def get_protocols(self, peer_id: ID) -> list[str]:
         """
         :param peer_id: peer ID to get protocols for
@@ -79,23 +158,31 @@ class PeerStore(IPeerStore):
         peer_data = self.peer_data_map[peer_id]
         peer_data.set_protocols(list(protocols))
 
-    def peer_ids(self) -> list[ID]:
+    def remove_protocols(self, peer_id: ID, protocols: Sequence[str]) -> None:
+        """
+        :param peer_id: peer ID to get info for
+        :param protocols: unsupported protocols to remove
+        """
+        peer_data = self.peer_data_map[peer_id]
+        peer_data.remove_protocols(protocols)
+
+    def supports_protocols(self, peer_id: ID, protocols: Sequence[str]) -> list[str]:
         """
         :return: all of the peer IDs stored in peer store
         """
-        return list(self.peer_data_map.keys())
+        peer_data = self.peer_data_map[peer_id]
+        return peer_data.supports_protocols(protocols)
 
-    def valid_peer_ids(self) -> list[ID]:
-        """
-        :return: all of the valid peer IDs stored in peer store
-        """
-        valid_peer_ids: list[ID] = []
-        for peer_id, peer_data in self.peer_data_map.items():
-            if not peer_data.is_expired():
-                valid_peer_ids.append(peer_id)
-            else:
-                peer_data.clear_addrs()
-        return valid_peer_ids
+    def first_supported_protocol(self, peer_id: ID, protocols: Sequence[str]) -> str:
+        peer_data = self.peer_data_map[peer_id]
+        return peer_data.first_supported_protocol(protocols)
+
+    def clear_protocol_data(self, peer_id: ID) -> None:
+        """Clears prtocoldata"""
+        peer_data = self.peer_data_map[peer_id]
+        peer_data.clear_protocol_data()
+
+    # ------METADATA---------
 
     def get(self, peer_id: ID, key: str) -> Any:
         """
@@ -121,6 +208,91 @@ class PeerStore(IPeerStore):
         peer_data = self.peer_data_map[peer_id]
         peer_data.put_metadata(key, val)
 
+    def clear_metadata(self, peer_id: ID) -> None:
+        """Clears metadata"""
+        peer_data = self.peer_data_map[peer_id]
+        peer_data.clear_metadata()
+
+    # -----CERT-ADDR-BOOK-----
+
+    def maybe_delete_peer_record(self, peer_id: ID) -> None:
+        """
+        Delete the signed peer record for a peer if it has no know
+        (non-expired) addresses.
+
+        This is a garbage collection mechanism: if all addresses for a peer have expired
+        or been cleared, there's no point holding onto its signed `Envelope`
+
+        :param peer_id: The peer whose record we may delete/
+        """
+        if peer_id in self.peer_record_map:
+            if not self.addrs(peer_id):
+                self.peer_record_map.pop(peer_id, None)
+
+    def consume_peer_record(self, envelope: Envelope, ttl: int) -> bool:
+        """
+        Accept and store a signed PeerRecord, unless it's older than
+        the one already stored.
+
+        This function:
+        - Extracts the peer ID and sequence number from the envelope
+        - Rejects the record if it's older (lower seq)
+        - Updates the stored peer record and replaces associated addresses if accepted
+
+        :param envelope: Signed envelope containing a PeerRecord.
+        :param ttl: Time-to-live for the included multiaddrs (in seconds).
+        :return: True if the record was accepted and stored; False if it was rejected.
+        """
+        record = envelope.record()
+        peer_id = record.peer_id
+
+        existing = self.peer_record_map.get(peer_id)
+        if existing and existing.seq > record.seq:
+            return False  # reject older record
+
+        new_addrs = set(record.addrs)
+
+        self.peer_record_map[peer_id] = PeerRecordState(envelope, record.seq)
+        self.peer_data_map[peer_id].clear_addrs()
+        self.add_addrs(peer_id, list(new_addrs), ttl)
+
+        return True
+
+    def consume_peer_records(self, envelopes: list[Envelope], ttl: int) -> list[bool]:
+        """Consume multiple peer records in a single operation."""
+        results = []
+        for envelope in envelopes:
+            results.append(self.consume_peer_record(envelope, ttl))
+        return results
+
+    def get_peer_record(self, peer_id: ID) -> Envelope | None:
+        """
+        Retrieve the most recent signed PeerRecord `Envelope` for a peer, if it exists
+        and is still relevant.
+
+        First, it runs cleanup via `maybe_delete_peer_record` to purge stale data.
+        Then it checks whether the peer has valid, unexpired addresses before
+        returning the associated envelope.
+
+        :param peer_id: The peer to look up.
+        :return: The signed Envelope if the peer is known and has valid
+            addresses; None otherwise.
+
+        """
+        self.maybe_delete_peer_record(peer_id)
+
+        # Check if the peer has any valid addresses
+        if (
+            peer_id in self.peer_data_map
+            and not self.peer_data_map[peer_id].is_expired()
+        ):
+            state = self.peer_record_map.get(peer_id)
+            if state is not None:
+                return state.envelope
+        return None
+
+    # -------ADDR-BOOK--------
+
     def add_addr(self, peer_id: ID, addr: Multiaddr, ttl: int = 0) -> None:
         """
         :param peer_id: peer ID to add address for
@@ -140,6 +312,15 @@ class PeerStore(IPeerStore):
         peer_data.set_ttl(ttl)
         peer_data.update_last_identified()
 
+        if peer_id in self.addr_update_channels:
+            for addr in addrs:
+                try:
+                    self.addr_update_channels[peer_id].send_nowait(addr)
+                except trio.WouldBlock:
+                    pass  # Or consider logging / dropping / replacing stream
+
+        self.maybe_delete_peer_record(peer_id)
+
     def addrs(self, peer_id: ID) -> list[Multiaddr]:
         """
         :param peer_id: peer ID to get addrs for
@@ -163,9 +344,11 @@ class PeerStore(IPeerStore):
         if peer_id in self.peer_data_map:
             self.peer_data_map[peer_id].clear_addrs()
 
+        self.maybe_delete_peer_record(peer_id)
+
     def peers_with_addrs(self) -> list[ID]:
         """
-        :return: all of the peer IDs which has addrs stored in peer store
+        :return: all of the peer IDs which has addrsfloat stored in peer store
         """
         # Add all peers with addrs at least 1 to output
         output: list[ID] = []
@@ -179,6 +362,27 @@ class PeerStore(IPeerStore):
                     peer_data.clear_addrs()
         return output
 
+    async def addr_stream(self, peer_id: ID) -> AsyncIterable[Multiaddr]:
+        """
+        Returns an async stream of newly added addresses for the given peer.
+
+        This function allows consumers to subscribe to address updates for a peer
+        and receive each new address as it is added via `add_addr` or `add_addrs`.
+
+        :param peer_id: The ID of the peer to monitor address updates for.
+        :return: An async iterator yielding Multiaddr instances as they are added.
+        """
+        send: MemorySendChannel[Multiaddr]
+        receive: MemoryReceiveChannel[Multiaddr]
+
+        send, receive = trio.open_memory_channel(0)
+        self.addr_update_channels[peer_id] = send
+
+        async for addr in receive:
+            yield addr
+
+    # -------KEY-BOOK---------
+
     def add_pubkey(self, peer_id: ID, pubkey: PublicKey) -> None:
         """
         :param peer_id: peer ID to add public key for
@@ -239,6 +443,45 @@ class PeerStore(IPeerStore):
         self.add_pubkey(peer_id, key_pair.public_key)
         self.add_privkey(peer_id, key_pair.private_key)
 
+    def peer_with_keys(self) -> list[ID]:
+        """Returns the peer_ids for which keys are stored"""
+        return [
+            peer_id
+            for peer_id, pdata in self.peer_data_map.items()
+            if pdata.pubkey is not None
+        ]
+
+    def clear_keydata(self, peer_id: ID) -> None:
+        """Clears the keys of the peer"""
+        peer_data = self.peer_data_map[peer_id]
+        peer_data.clear_keydata()
+
+    # --------METRICS--------
+
+    def record_latency(self, peer_id: ID, RTT: float) -> None:
+        """
+        Records a new latency measurement for the given peer
+        using Exponentially Weighted Moving Average (EWMA)
+
+        :param peer_id: peer ID to get private key for
+        :param RTT: the new latency value (round trip time)
+        """
+        peer_data = self.peer_data_map[peer_id]
+        peer_data.record_latency(RTT)
+
+    def latency_EWMA(self, peer_id: ID) -> float:
+        """
+        :param peer_id: peer ID to get private key for
+        :return: The latency EWMA value for that peer
+        """
+        peer_data = self.peer_data_map[peer_id]
+        return peer_data.latency_EWMA()
+
+    def clear_metrics(self, peer_id: ID) -> None:
+        """Clear the latency metrics"""
+        peer_data = self.peer_data_map[peer_id]
+        peer_data.clear_metrics()
+
 
 class PeerStoreError(KeyError):
     """Raised when peer ID is not found in peer store."""

libp2p/protocol_muxer/multiselect.py

@@ -1,3 +1,5 @@
+import trio
+
 from libp2p.abc import (
     IMultiselectCommunicator,
     IMultiselectMuxer,
@@ -14,6 +16,7 @@ from .exceptions import (
 
 MULTISELECT_PROTOCOL_ID = "/multistream/1.0.0"
 PROTOCOL_NOT_FOUND_MSG = "na"
+DEFAULT_NEGOTIATE_TIMEOUT = 5
 
 
 class Multiselect(IMultiselectMuxer):
@@ -47,47 +50,68 @@ class Multiselect(IMultiselectMuxer):
 
     # FIXME: Make TProtocol Optional[TProtocol] to keep types consistent
     async def negotiate(
-        self, communicator: IMultiselectCommunicator
+        self,
+        communicator: IMultiselectCommunicator,
+        negotiate_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
     ) -> tuple[TProtocol, StreamHandlerFn | None]:
         """
         Negotiate performs protocol selection.
 
         :param stream: stream to negotiate on
+        :param negotiate_timeout: timeout for negotiation
         :return: selected protocol name, handler function
         :raise MultiselectError: raised when negotiation failed
         """
-        await self.handshake(communicator)
+        try:
+            with trio.fail_after(negotiate_timeout):
+                await self.handshake(communicator)
 
-        while True:
-            try:
-                command = await communicator.read()
-            except MultiselectCommunicatorError as error:
-                raise MultiselectError() from error
-
-            if command == "ls":
-                supported_protocols = [p for p in self.handlers.keys() if p is not None]
-                response = "\n".join(supported_protocols) + "\n"
-
-                try:
-                    await communicator.write(response)
-                except MultiselectCommunicatorError as error:
-                    raise MultiselectError() from error
-
-            else:
-                protocol = TProtocol(command)
-                if protocol in self.handlers:
+                while True:
                     try:
-                        await communicator.write(protocol)
+                        command = await communicator.read()
                     except MultiselectCommunicatorError as error:
                         raise MultiselectError() from error
 
-                    return protocol, self.handlers[protocol]
-                try:
-                    await communicator.write(PROTOCOL_NOT_FOUND_MSG)
-                except MultiselectCommunicatorError as error:
-                    raise MultiselectError() from error
+                    if command == "ls":
+                        supported_protocols = [
+                            p for p in self.handlers.keys() if p is not None
+                        ]
+                        response = "\n".join(supported_protocols) + "\n"
 
-        raise MultiselectError("Negotiation failed: no matching protocol")
+                        try:
+                            await communicator.write(response)
+                        except MultiselectCommunicatorError as error:
+                            raise MultiselectError() from error
+
+                    else:
+                        protocol = TProtocol(command)
+                        if protocol in self.handlers:
+                            try:
+                                await communicator.write(protocol)
+                            except MultiselectCommunicatorError as error:
+                                raise MultiselectError() from error
+
+                            return protocol, self.handlers[protocol]
+                        try:
+                            await communicator.write(PROTOCOL_NOT_FOUND_MSG)
+                        except MultiselectCommunicatorError as error:
+                            raise MultiselectError() from error
+
+                raise MultiselectError("Negotiation failed: no matching protocol")
+        except trio.TooSlowError:
+            raise MultiselectError("handshake read timeout")
+
+    def get_protocols(self) -> tuple[TProtocol | None, ...]:
+        """
+        Retrieve the protocols for which handlers have been registered.
+
+        Returns
+        -------
+        tuple[TProtocol, ...]
+            A tuple of registered protocol names.
+
+        """
+        return tuple(self.handlers.keys())
 
     async def handshake(self, communicator: IMultiselectCommunicator) -> None:
         """

libp2p/protocol_muxer/multiselect_client.py

@@ -2,6 +2,8 @@ from collections.abc import (
     Sequence,
 )
 
+import trio
+
 from libp2p.abc import (
     IMultiselectClient,
     IMultiselectCommunicator,
@@ -17,6 +19,7 @@ from .exceptions import (
 
 MULTISELECT_PROTOCOL_ID = "/multistream/1.0.0"
 PROTOCOL_NOT_FOUND_MSG = "na"
+DEFAULT_NEGOTIATE_TIMEOUT = 5
 
 
 class MultiselectClient(IMultiselectClient):
@@ -40,6 +43,7 @@ class MultiselectClient(IMultiselectClient):
 
         try:
             handshake_contents = await communicator.read()
+
         except MultiselectCommunicatorError as error:
             raise MultiselectClientError() from error
 
@@ -47,7 +51,10 @@ class MultiselectClient(IMultiselectClient):
             raise MultiselectClientError("multiselect protocol ID mismatch")
 
     async def select_one_of(
-        self, protocols: Sequence[TProtocol], communicator: IMultiselectCommunicator
+        self,
+        protocols: Sequence[TProtocol],
+        communicator: IMultiselectCommunicator,
+        negotitate_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
     ) -> TProtocol:
         """
         For each protocol, send message to multiselect selecting protocol and
@@ -56,22 +63,32 @@ class MultiselectClient(IMultiselectClient):
 
         :param protocol: protocol to select
         :param communicator: communicator to use to communicate with counterparty
+        :param negotiate_timeout: timeout for negotiation
         :return: selected protocol
         :raise MultiselectClientError: raised when protocol negotiation failed
         """
-        await self.handshake(communicator)
+        try:
+            with trio.fail_after(negotitate_timeout):
+                await self.handshake(communicator)
 
-        for protocol in protocols:
-            try:
-                selected_protocol = await self.try_select(communicator, protocol)
-                return selected_protocol
-            except MultiselectClientError:
-                pass
+                for protocol in protocols:
+                    try:
+                        selected_protocol = await self.try_select(
+                            communicator, protocol
+                        )
+                        return selected_protocol
+                    except MultiselectClientError:
+                        pass
 
-        raise MultiselectClientError("protocols not supported")
+                raise MultiselectClientError("protocols not supported")
+        except trio.TooSlowError:
+            raise MultiselectClientError("response timed out")
 
     async def query_multistream_command(
-        self, communicator: IMultiselectCommunicator, command: str
+        self,
+        communicator: IMultiselectCommunicator,
+        command: str,
+        response_timeout: int = DEFAULT_NEGOTIATE_TIMEOUT,
     ) -> list[str]:
         """
         Send a multistream-select command over the given communicator and return
@@ -79,26 +96,32 @@ class MultiselectClient(IMultiselectClient):
 
         :param communicator: communicator to use to communicate with counterparty
         :param command: supported multistream-select command(e.g., ls)
+        :param negotiate_timeout: timeout for negotiation
         :raise MultiselectClientError: If the communicator fails to process data.
         :return: list of strings representing the response from peer.
         """
-        await self.handshake(communicator)
-
-        if command == "ls":
-            try:
-                await communicator.write("ls")
-            except MultiselectCommunicatorError as error:
-                raise MultiselectClientError() from error
-        else:
-            raise ValueError("Command not supported")
-
         try:
-            response = await communicator.read()
-            response_list = response.strip().splitlines()
-        except MultiselectCommunicatorError as error:
-            raise MultiselectClientError() from error
+            with trio.fail_after(response_timeout):
+                await self.handshake(communicator)
 
-        return response_list
+                if command == "ls":
+                    try:
+                        await communicator.write("ls")
+                    except MultiselectCommunicatorError as error:
+                        raise MultiselectClientError() from error
+                else:
+                    raise ValueError("Command not supported")
+
+                try:
+                    response = await communicator.read()
+                    response_list = response.strip().splitlines()
+
+                except MultiselectCommunicatorError as error:
+                    raise MultiselectClientError() from error
+
+                return response_list
+        except trio.TooSlowError:
+            raise MultiselectClientError("command response timed out")
 
     async def try_select(
         self, communicator: IMultiselectCommunicator, protocol: TProtocol
@@ -118,6 +141,7 @@ class MultiselectClient(IMultiselectClient):
 
         try:
             response = await communicator.read()
+
         except MultiselectCommunicatorError as error:
             raise MultiselectClientError() from error
 

libp2p/pubsub/floodsub.py

@@ -12,15 +12,9 @@ from libp2p.abc import (
 from libp2p.custom_types import (
     TProtocol,
 )
-from libp2p.network.stream.exceptions import (
-    StreamClosed,
-)
 from libp2p.peer.id import (
     ID,
 )
-from libp2p.utils import (
-    encode_varint_prefixed,
-)
 
 from .exceptions import (
     PubsubRouterError,
@@ -120,13 +114,7 @@ class FloodSub(IPubsubRouter):
             if peer_id not in pubsub.peers:
                 continue
             stream = pubsub.peers[peer_id]
-            # FIXME: We should add a `WriteMsg` similar to write delimited messages.
-            #   Ref: https://github.com/libp2p/go-libp2p-pubsub/blob/master/comm.go#L107
-            try:
-                await stream.write(encode_varint_prefixed(rpc_msg.SerializeToString()))
-            except StreamClosed:
-                logger.debug("Fail to publish message to %s: stream closed", peer_id)
-                pubsub._handle_dead_peer(peer_id)
+            await pubsub.write_msg(stream, rpc_msg)
 
     async def join(self, topic: str) -> None:
         """

libp2p/pubsub/gossipsub.py

@@ -24,9 +24,6 @@ from libp2p.abc import (
 from libp2p.custom_types import (
     TProtocol,
 )
-from libp2p.network.stream.exceptions import (
-    StreamClosed,
-)
 from libp2p.peer.id import (
     ID,
 )
@@ -44,9 +41,6 @@ from libp2p.pubsub import (
 from libp2p.tools.async_service import (
     Service,
 )
-from libp2p.utils import (
-    encode_varint_prefixed,
-)
 
 from .exceptions import (
     NoPubsubAttached,
@@ -267,13 +261,10 @@ class GossipSub(IPubsubRouter, Service):
             if peer_id not in self.pubsub.peers:
                 continue
             stream = self.pubsub.peers[peer_id]
-            # FIXME: We should add a `WriteMsg` similar to write delimited messages.
-            #   Ref: https://github.com/libp2p/go-libp2p-pubsub/blob/master/comm.go#L107
-            try:
-                await stream.write(encode_varint_prefixed(rpc_msg.SerializeToString()))
-            except StreamClosed:
-                logger.debug("Fail to publish message to %s: stream closed", peer_id)
-                self.pubsub._handle_dead_peer(peer_id)
+
+            # TODO: Go use `sendRPC`, which possibly piggybacks gossip/control messages.
+            await self.pubsub.write_msg(stream, rpc_msg)
+
         for topic in pubsub_msg.topicIDs:
             self.time_since_last_publish[topic] = int(time.time())
 
@@ -829,8 +820,6 @@ class GossipSub(IPubsubRouter, Service):
 
         packet.publish.extend(msgs_to_forward)
 
-        # 2) Serialize that packet
-        rpc_msg: bytes = packet.SerializeToString()
         if self.pubsub is None:
             raise NoPubsubAttached
 
@@ -844,14 +833,7 @@ class GossipSub(IPubsubRouter, Service):
         peer_stream = self.pubsub.peers[sender_peer_id]
 
         # 4) And write the packet to the stream
-        try:
-            await peer_stream.write(encode_varint_prefixed(rpc_msg))
-        except StreamClosed:
-            logger.debug(
-                "Fail to responed to iwant request from %s: stream closed",
-                sender_peer_id,
-            )
-            self.pubsub._handle_dead_peer(sender_peer_id)
+        await self.pubsub.write_msg(peer_stream, packet)
 
     async def handle_graft(
         self, graft_msg: rpc_pb2.ControlGraft, sender_peer_id: ID
@@ -993,8 +975,6 @@ class GossipSub(IPubsubRouter, Service):
         packet: rpc_pb2.RPC = rpc_pb2.RPC()
         packet.control.CopyFrom(control_msg)
 
-        rpc_msg: bytes = packet.SerializeToString()
-
         # Get stream for peer from pubsub
         if to_peer not in self.pubsub.peers:
             logger.debug(
@@ -1004,8 +984,4 @@ class GossipSub(IPubsubRouter, Service):
         peer_stream = self.pubsub.peers[to_peer]
 
         # Write rpc to stream
-        try:
-            await peer_stream.write(encode_varint_prefixed(rpc_msg))
-        except StreamClosed:
-            logger.debug("Fail to emit control message to %s: stream closed", to_peer)
-            self.pubsub._handle_dead_peer(to_peer)
+        await self.pubsub.write_msg(peer_stream, packet)

libp2p/pubsub/pb/rpc_pb2.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
-# source: rpc.proto
+# source: libp2p/pubsub/pb/rpc.proto
 """Generated protocol buffer code."""
 from google.protobuf.internal import builder as _builder
 from google.protobuf import descriptor as _descriptor
@@ -13,39 +13,39 @@ _sym_db = _symbol_database.Default()
 
 
 
-DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\trpc.proto\x12\tpubsub.pb\"\xb4\x01\n\x03RPC\x12-\n\rsubscriptions\x18\x01 \x03(\x0b\x32\x16.pubsub.pb.RPC.SubOpts\x12#\n\x07publish\x18\x02 \x03(\x0b\x32\x12.pubsub.pb.Message\x12*\n\x07\x63ontrol\x18\x03 \x01(\x0b\x32\x19.pubsub.pb.ControlMessage\x1a-\n\x07SubOpts\x12\x11\n\tsubscribe\x18\x01 \x01(\x08\x12\x0f\n\x07topicid\x18\x02 \x01(\t\"i\n\x07Message\x12\x0f\n\x07\x66rom_id\x18\x01 \x01(\x0c\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x0c\x12\r\n\x05seqno\x18\x03 \x01(\x0c\x12\x10\n\x08topicIDs\x18\x04 \x03(\t\x12\x11\n\tsignature\x18\x05 \x01(\x0c\x12\x0b\n\x03key\x18\x06 \x01(\x0c\"\xb0\x01\n\x0e\x43ontrolMessage\x12&\n\x05ihave\x18\x01 \x03(\x0b\x32\x17.pubsub.pb.ControlIHave\x12&\n\x05iwant\x18\x02 \x03(\x0b\x32\x17.pubsub.pb.ControlIWant\x12&\n\x05graft\x18\x03 \x03(\x0b\x32\x17.pubsub.pb.ControlGraft\x12&\n\x05prune\x18\x04 \x03(\x0b\x32\x17.pubsub.pb.ControlPrune\"3\n\x0c\x43ontrolIHave\x12\x0f\n\x07topicID\x18\x01 \x01(\t\x12\x12\n\nmessageIDs\x18\x02 \x03(\t\"\"\n\x0c\x43ontrolIWant\x12\x12\n\nmessageIDs\x18\x01 \x03(\t\"\x1f\n\x0c\x43ontrolGraft\x12\x0f\n\x07topicID\x18\x01 \x01(\t\"T\n\x0c\x43ontrolPrune\x12\x0f\n\x07topicID\x18\x01 \x01(\t\x12\"\n\x05peers\x18\x02 \x03(\x0b\x32\x13.pubsub.pb.PeerInfo\x12\x0f\n\x07\x62\x61\x63koff\x18\x03 \x01(\x04\"4\n\x08PeerInfo\x12\x0e\n\x06peerID\x18\x01 \x01(\x0c\x12\x18\n\x10signedPeerRecord\x18\x02 \x01(\x0c\"\x87\x03\n\x0fTopicDescriptor\x12\x0c\n\x04name\x18\x01 \x01(\t\x12\x31\n\x04\x61uth\x18\x02 \x01(\x0b\x32#.pubsub.pb.TopicDescriptor.AuthOpts\x12/\n\x03\x65nc\x18\x03 \x01(\x0b\x32\".pubsub.pb.TopicDescriptor.EncOpts\x1a|\n\x08\x41uthOpts\x12:\n\x04mode\x18\x01 \x01(\x0e\x32,.pubsub.pb.TopicDescriptor.AuthOpts.AuthMode\x12\x0c\n\x04keys\x18\x02 \x03(\x0c\"&\n\x08\x41uthMode\x12\x08\n\x04NONE\x10\x00\x12\x07\n\x03KEY\x10\x01\x12\x07\n\x03WOT\x10\x02\x1a\x83\x01\n\x07\x45ncOpts\x12\x38\n\x04mode\x18\x01 \x01(\x0e\x32*.pubsub.pb.TopicDescriptor.EncOpts.EncMode\x12\x11\n\tkeyHashes\x18\x02 \x03(\x0c\"+\n\x07\x45ncMode\x12\x08\n\x04NONE\x10\x00\x12\r\n\tSHAREDKEY\x10\x01\x12\x07\n\x03WOT\x10\x02')
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1alibp2p/pubsub/pb/rpc.proto\x12\tpubsub.pb\"\xb4\x01\n\x03RPC\x12-\n\rsubscriptions\x18\x01 \x03(\x0b\x32\x16.pubsub.pb.RPC.SubOpts\x12#\n\x07publish\x18\x02 \x03(\x0b\x32\x12.pubsub.pb.Message\x12*\n\x07\x63ontrol\x18\x03 \x01(\x0b\x32\x19.pubsub.pb.ControlMessage\x1a-\n\x07SubOpts\x12\x11\n\tsubscribe\x18\x01 \x01(\x08\x12\x0f\n\x07topicid\x18\x02 \x01(\t\"i\n\x07Message\x12\x0f\n\x07\x66rom_id\x18\x01 \x01(\x0c\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x0c\x12\r\n\x05seqno\x18\x03 \x01(\x0c\x12\x10\n\x08topicIDs\x18\x04 \x03(\t\x12\x11\n\tsignature\x18\x05 \x01(\x0c\x12\x0b\n\x03key\x18\x06 \x01(\x0c\"\xb0\x01\n\x0e\x43ontrolMessage\x12&\n\x05ihave\x18\x01 \x03(\x0b\x32\x17.pubsub.pb.ControlIHave\x12&\n\x05iwant\x18\x02 \x03(\x0b\x32\x17.pubsub.pb.ControlIWant\x12&\n\x05graft\x18\x03 \x03(\x0b\x32\x17.pubsub.pb.ControlGraft\x12&\n\x05prune\x18\x04 \x03(\x0b\x32\x17.pubsub.pb.ControlPrune\"3\n\x0c\x43ontrolIHave\x12\x0f\n\x07topicID\x18\x01 \x01(\t\x12\x12\n\nmessageIDs\x18\x02 \x03(\t\"\"\n\x0c\x43ontrolIWant\x12\x12\n\nmessageIDs\x18\x01 \x03(\t\"\x1f\n\x0c\x43ontrolGraft\x12\x0f\n\x07topicID\x18\x01 \x01(\t\"T\n\x0c\x43ontrolPrune\x12\x0f\n\x07topicID\x18\x01 \x01(\t\x12\"\n\x05peers\x18\x02 \x03(\x0b\x32\x13.pubsub.pb.PeerInfo\x12\x0f\n\x07\x62\x61\x63koff\x18\x03 \x01(\x04\"4\n\x08PeerInfo\x12\x0e\n\x06peerID\x18\x01 \x01(\x0c\x12\x18\n\x10signedPeerRecord\x18\x02 \x01(\x0c\"\x87\x03\n\x0fTopicDescriptor\x12\x0c\n\x04name\x18\x01 \x01(\t\x12\x31\n\x04\x61uth\x18\x02 \x01(\x0b\x32#.pubsub.pb.TopicDescriptor.AuthOpts\x12/\n\x03\x65nc\x18\x03 \x01(\x0b\x32\".pubsub.pb.TopicDescriptor.EncOpts\x1a|\n\x08\x41uthOpts\x12:\n\x04mode\x18\x01 \x01(\x0e\x32,.pubsub.pb.TopicDescriptor.AuthOpts.AuthMode\x12\x0c\n\x04keys\x18\x02 \x03(\x0c\"&\n\x08\x41uthMode\x12\x08\n\x04NONE\x10\x00\x12\x07\n\x03KEY\x10\x01\x12\x07\n\x03WOT\x10\x02\x1a\x83\x01\n\x07\x45ncOpts\x12\x38\n\x04mode\x18\x01 \x01(\x0e\x32*.pubsub.pb.TopicDescriptor.EncOpts.EncMode\x12\x11\n\tkeyHashes\x18\x02 \x03(\x0c\"+\n\x07\x45ncMode\x12\x08\n\x04NONE\x10\x00\x12\r\n\tSHAREDKEY\x10\x01\x12\x07\n\x03WOT\x10\x02')
 
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
-_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'rpc_pb2', globals())
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.pubsub.pb.rpc_pb2', globals())
 if _descriptor._USE_C_DESCRIPTORS == False:
 
   DESCRIPTOR._options = None
-  _RPC._serialized_start=25
-  _RPC._serialized_end=205
-  _RPC_SUBOPTS._serialized_start=160
-  _RPC_SUBOPTS._serialized_end=205
-  _MESSAGE._serialized_start=207
-  _MESSAGE._serialized_end=312
-  _CONTROLMESSAGE._serialized_start=315
-  _CONTROLMESSAGE._serialized_end=491
-  _CONTROLIHAVE._serialized_start=493
-  _CONTROLIHAVE._serialized_end=544
-  _CONTROLIWANT._serialized_start=546
-  _CONTROLIWANT._serialized_end=580
-  _CONTROLGRAFT._serialized_start=582
-  _CONTROLGRAFT._serialized_end=613
-  _CONTROLPRUNE._serialized_start=615
-  _CONTROLPRUNE._serialized_end=699
-  _PEERINFO._serialized_start=701
-  _PEERINFO._serialized_end=753
-  _TOPICDESCRIPTOR._serialized_start=756
-  _TOPICDESCRIPTOR._serialized_end=1147
-  _TOPICDESCRIPTOR_AUTHOPTS._serialized_start=889
-  _TOPICDESCRIPTOR_AUTHOPTS._serialized_end=1013
-  _TOPICDESCRIPTOR_AUTHOPTS_AUTHMODE._serialized_start=975
-  _TOPICDESCRIPTOR_AUTHOPTS_AUTHMODE._serialized_end=1013
-  _TOPICDESCRIPTOR_ENCOPTS._serialized_start=1016
-  _TOPICDESCRIPTOR_ENCOPTS._serialized_end=1147
-  _TOPICDESCRIPTOR_ENCOPTS_ENCMODE._serialized_start=1104
-  _TOPICDESCRIPTOR_ENCOPTS_ENCMODE._serialized_end=1147
+  _RPC._serialized_start=42
+  _RPC._serialized_end=222
+  _RPC_SUBOPTS._serialized_start=177
+  _RPC_SUBOPTS._serialized_end=222
+  _MESSAGE._serialized_start=224
+  _MESSAGE._serialized_end=329
+  _CONTROLMESSAGE._serialized_start=332
+  _CONTROLMESSAGE._serialized_end=508
+  _CONTROLIHAVE._serialized_start=510
+  _CONTROLIHAVE._serialized_end=561
+  _CONTROLIWANT._serialized_start=563
+  _CONTROLIWANT._serialized_end=597
+  _CONTROLGRAFT._serialized_start=599
+  _CONTROLGRAFT._serialized_end=630
+  _CONTROLPRUNE._serialized_start=632
+  _CONTROLPRUNE._serialized_end=716
+  _PEERINFO._serialized_start=718
+  _PEERINFO._serialized_end=770
+  _TOPICDESCRIPTOR._serialized_start=773
+  _TOPICDESCRIPTOR._serialized_end=1164
+  _TOPICDESCRIPTOR_AUTHOPTS._serialized_start=906
+  _TOPICDESCRIPTOR_AUTHOPTS._serialized_end=1030
+  _TOPICDESCRIPTOR_AUTHOPTS_AUTHMODE._serialized_start=992
+  _TOPICDESCRIPTOR_AUTHOPTS_AUTHMODE._serialized_end=1030
+  _TOPICDESCRIPTOR_ENCOPTS._serialized_start=1033
+  _TOPICDESCRIPTOR_ENCOPTS._serialized_end=1164
+  _TOPICDESCRIPTOR_ENCOPTS_ENCMODE._serialized_start=1121
+  _TOPICDESCRIPTOR_ENCOPTS_ENCMODE._serialized_end=1164
 # @@protoc_insertion_point(module_scope)

libp2p/pubsub/pubsub.py

@@ -66,6 +66,7 @@ from libp2p.utils import (
     encode_varint_prefixed,
     read_varint_prefixed_bytes,
 )
+from libp2p.utils.varint import encode_uvarint
 
 from .pb import (
     rpc_pb2,
@@ -101,6 +102,9 @@ class TopicValidator(NamedTuple):
     is_async: bool
 
 
+MAX_CONCURRENT_VALIDATORS = 10
+
+
 class Pubsub(Service, IPubsub):
     host: IHost
 
@@ -108,6 +112,7 @@ class Pubsub(Service, IPubsub):
 
     peer_receive_channel: trio.MemoryReceiveChannel[ID]
     dead_peer_receive_channel: trio.MemoryReceiveChannel[ID]
+    _validator_semaphore: trio.Semaphore
 
     seen_messages: LastSeenCache
 
@@ -142,6 +147,7 @@ class Pubsub(Service, IPubsub):
         msg_id_constructor: Callable[
             [rpc_pb2.Message], bytes
         ] = get_peer_and_seqno_msg_id,
+        max_concurrent_validator_count: int = MAX_CONCURRENT_VALIDATORS,
     ) -> None:
         """
         Construct a new Pubsub object, which is responsible for handling all
@@ -167,6 +173,7 @@ class Pubsub(Service, IPubsub):
         # Therefore, we can only close from the receive side.
         self.peer_receive_channel = peer_receive
         self.dead_peer_receive_channel = dead_peer_receive
+        self._validator_semaphore = trio.Semaphore(max_concurrent_validator_count)
         # Register a notifee
         self.host.get_network().register_notifee(
             PubsubNotifee(peer_send, dead_peer_send)
@@ -656,7 +663,11 @@ class Pubsub(Service, IPubsub):
 
         logger.debug("successfully published message %s", msg)
 
-    async def validate_msg(self, msg_forwarder: ID, msg: rpc_pb2.Message) -> None:
+    async def validate_msg(
+        self,
+        msg_forwarder: ID,
+        msg: rpc_pb2.Message,
+    ) -> None:
         """
         Validate the received message.
 
@@ -679,24 +690,34 @@ class Pubsub(Service, IPubsub):
             if not validator(msg_forwarder, msg):
                 raise ValidationError(f"Validation failed for msg={msg}")
 
-        # TODO: Implement throttle on async validators
-
         if len(async_topic_validators) > 0:
-            # TODO: Use a better pattern
-            final_result: bool = True
-
-            async def run_async_validator(func: AsyncValidatorFn) -> None:
-                nonlocal final_result
-                result = await func(msg_forwarder, msg)
-                final_result = final_result and result
+            # Appends to lists are thread safe in CPython
+            results: list[bool] = []
 
             async with trio.open_nursery() as nursery:
                 for async_validator in async_topic_validators:
-                    nursery.start_soon(run_async_validator, async_validator)
+                    nursery.start_soon(
+                        self._run_async_validator,
+                        async_validator,
+                        msg_forwarder,
+                        msg,
+                        results,
+                    )
 
-            if not final_result:
+            if not all(results):
                 raise ValidationError(f"Validation failed for msg={msg}")
 
+    async def _run_async_validator(
+        self,
+        func: AsyncValidatorFn,
+        msg_forwarder: ID,
+        msg: rpc_pb2.Message,
+        results: list[bool],
+    ) -> None:
+        async with self._validator_semaphore:
+            result = await func(msg_forwarder, msg)
+            results.append(result)
+
     async def push_msg(self, msg_forwarder: ID, msg: rpc_pb2.Message) -> None:
         """
         Push a pubsub message to others.
@@ -779,3 +800,43 @@ class Pubsub(Service, IPubsub):
 
     def _is_subscribed_to_msg(self, msg: rpc_pb2.Message) -> bool:
         return any(topic in self.topic_ids for topic in msg.topicIDs)
+
+    async def write_msg(self, stream: INetStream, rpc_msg: rpc_pb2.RPC) -> bool:
+        """
+        Write an RPC message to a stream with proper error handling.
+
+        Implements WriteMsg similar to go-msgio which is used in go-libp2p
+        Ref: https://github.com/libp2p/go-msgio/blob/master/protoio/uvarint_writer.go#L56
+
+
+        :param stream: stream to write the message to
+        :param rpc_msg: RPC message to write
+        :return: True if successful, False if stream was closed
+        """
+        try:
+            # Calculate message size first
+            msg_bytes = rpc_msg.SerializeToString()
+            msg_size = len(msg_bytes)
+
+            # Calculate varint size and allocate exact buffer size needed
+
+            varint_bytes = encode_uvarint(msg_size)
+            varint_size = len(varint_bytes)
+
+            # Allocate buffer with exact size (like Go's pool.Get())
+            buf = bytearray(varint_size + msg_size)
+
+            # Write varint length prefix to buffer (like Go's binary.PutUvarint())
+            buf[:varint_size] = varint_bytes
+
+            # Write serialized message after varint (like Go's rpc.MarshalTo())
+            buf[varint_size:] = msg_bytes
+
+            # Single write operation (like Go's s.Write(buf))
+            await stream.write(bytes(buf))
+            return True
+        except StreamClosed:
+            peer_id = stream.muxed_conn.peer_id
+            logger.debug("Fail to write message to %s: stream closed", peer_id)
+            self._handle_dead_peer(peer_id)
+            return False

libp2p/relay/__init__.py

@@ -15,6 +15,10 @@ from libp2p.relay.circuit_v2 import (
     RelayLimits,
     RelayResourceManager,
     Reservation,
+     DCUTR_PROTOCOL_ID,
+    DCUtRProtocol,
+    ReachabilityChecker,
+    is_private_ip,
 )
 
 __all__ = [
@@ -25,4 +29,9 @@ __all__ = [
     "RelayLimits",
     "RelayResourceManager",
     "Reservation",
+    "DCUtRProtocol",
+    "DCUTR_PROTOCOL_ID",
+    "ReachabilityChecker",
+    "is_private_ip"
+
 ]

libp2p/relay/circuit_v2/__init__.py

@@ -5,6 +5,16 @@ This package implements the Circuit Relay v2 protocol as specified in:
 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 @@ __all__ = [
     "RelayResourceManager",
     "CircuitV2Transport",
     "RelayDiscovery",
+     "DCUtRProtocol",
+    "DCUTR_PROTOCOL_ID",
+    "ReachabilityChecker",
+    "is_private_ip",
 ]

libp2p/relay/circuit_v2/dcutr.py

@@ -0,0 +1,580 @@
+"""
+Direct Connection Upgrade through Relay (DCUtR) protocol implementation.
+
+This module implements the DCUtR protocol as specified in:
+https://github.com/libp2p/specs/blob/master/relay/DCUtR.md
+
+DCUtR enables peers behind NAT to establish direct connections
+using hole punching techniques.
+"""
+
+import logging
+import time
+from typing import Any
+
+from multiaddr import Multiaddr
+import trio
+
+from libp2p.abc import (
+    IHost,
+    INetConn,
+    INetStream,
+)
+from libp2p.custom_types import (
+    TProtocol,
+)
+from libp2p.peer.id import (
+    ID,
+)
+from libp2p.peer.peerinfo import (
+    PeerInfo,
+)
+from libp2p.relay.circuit_v2.nat import (
+    ReachabilityChecker,
+)
+from libp2p.relay.circuit_v2.pb.dcutr_pb2 import (
+    HolePunch,
+)
+from libp2p.tools.async_service import (
+    Service,
+)
+
+logger = logging.getLogger(__name__)
+
+# Protocol ID for DCUtR
+PROTOCOL_ID = TProtocol("/libp2p/dcutr")
+
+# Maximum message size for DCUtR (4KiB as per spec)
+MAX_MESSAGE_SIZE = 4 * 1024
+
+# Timeouts
+STREAM_READ_TIMEOUT = 30  # seconds
+STREAM_WRITE_TIMEOUT = 30  # seconds
+DIAL_TIMEOUT = 10  # seconds
+
+# Maximum number of hole punch attempts per peer
+MAX_HOLE_PUNCH_ATTEMPTS = 5
+
+# Delay between retry attempts
+HOLE_PUNCH_RETRY_DELAY = 30  # seconds
+
+# Maximum observed addresses to exchange
+MAX_OBSERVED_ADDRS = 20
+
+
+class DCUtRProtocol(Service):
+    """
+    DCUtRProtocol implements the Direct Connection Upgrade through Relay protocol.
+
+    This protocol allows two NATed peers to establish direct connections through
+    hole punching, after they have established an initial connection through a relay.
+    """
+
+    def __init__(self, host: IHost):
+        """
+        Initialize the DCUtR protocol.
+
+        Parameters
+        ----------
+        host : IHost
+            The libp2p host this protocol is running on
+
+        """
+        super().__init__()
+        self.host = host
+        self.event_started = trio.Event()
+        self._hole_punch_attempts: dict[ID, int] = {}
+        self._direct_connections: set[ID] = set()
+        self._in_progress: set[ID] = set()
+        self._reachability_checker = ReachabilityChecker(host)
+        self._nursery: trio.Nursery | None = None
+
+    async def run(self, *, task_status: Any = trio.TASK_STATUS_IGNORED) -> None:
+        """Run the protocol service."""
+        try:
+            # Register the DCUtR protocol handler
+            logger.debug("Registering DCUtR protocol handler")
+            self.host.set_stream_handler(PROTOCOL_ID, self._handle_dcutr_stream)
+
+            # Signal that we're ready
+            self.event_started.set()
+
+            # Start the service
+            async with trio.open_nursery() as nursery:
+                self._nursery = nursery
+                task_status.started()
+                logger.debug("DCUtR protocol service started")
+
+                # Wait for service to be stopped
+                await self.manager.wait_finished()
+        finally:
+            # Clean up
+            try:
+                # Use empty async lambda instead of None for stream handler
+                async def empty_handler(_: INetStream) -> None:
+                    pass
+
+                self.host.set_stream_handler(PROTOCOL_ID, empty_handler)
+                logger.debug("DCUtR protocol handler unregistered")
+            except Exception as e:
+                logger.error("Error unregistering DCUtR protocol handler: %s", str(e))
+
+            # Clear state
+            self._hole_punch_attempts.clear()
+            self._direct_connections.clear()
+            self._in_progress.clear()
+            self._nursery = None
+
+    async def _handle_dcutr_stream(self, stream: INetStream) -> None:
+        """
+        Handle incoming DCUtR streams.
+
+        Parameters
+        ----------
+        stream : INetStream
+            The incoming stream
+
+        """
+        try:
+            # Get the remote peer ID
+            remote_peer_id = stream.muxed_conn.peer_id
+            logger.debug("Received DCUtR stream from peer %s", remote_peer_id)
+
+            # Check if we already have a direct connection
+            if await self._have_direct_connection(remote_peer_id):
+                logger.debug(
+                    "Already have direct connection to %s, closing stream",
+                    remote_peer_id,
+                )
+                await stream.close()
+                return
+
+            # Check if there's already an active hole punch attempt
+            if remote_peer_id in self._in_progress:
+                logger.debug("Hole punch already in progress with %s", remote_peer_id)
+                # Let the existing attempt continue
+                await stream.close()
+                return
+
+            # Mark as in progress
+            self._in_progress.add(remote_peer_id)
+
+            try:
+                # Read the CONNECT message
+                with trio.fail_after(STREAM_READ_TIMEOUT):
+                    msg_bytes = await stream.read(MAX_MESSAGE_SIZE)
+
+                # Parse the message
+                connect_msg = HolePunch()
+                connect_msg.ParseFromString(msg_bytes)
+
+                # Verify it's a CONNECT message
+                if connect_msg.type != HolePunch.CONNECT:
+                    logger.warning("Expected CONNECT message, got %s", connect_msg.type)
+                    await stream.close()
+                    return
+
+                logger.debug(
+                    "Received CONNECT message from %s with %d addresses",
+                    remote_peer_id,
+                    len(connect_msg.ObsAddrs),
+                )
+
+                # Process observed addresses from the peer
+                peer_addrs = self._decode_observed_addrs(list(connect_msg.ObsAddrs))
+                logger.debug("Decoded %d valid addresses from peer", len(peer_addrs))
+
+                # Store the addresses in the peerstore
+                if peer_addrs:
+                    self.host.get_peerstore().add_addrs(
+                        remote_peer_id, peer_addrs, 10 * 60
+                    )  # 10 minute TTL
+
+                # Send our CONNECT message with our observed addresses
+                our_addrs = await self._get_observed_addrs()
+                response = HolePunch()
+                response.type = HolePunch.CONNECT
+                response.ObsAddrs.extend(our_addrs)
+
+                with trio.fail_after(STREAM_WRITE_TIMEOUT):
+                    await stream.write(response.SerializeToString())
+
+                logger.debug(
+                    "Sent CONNECT response to %s with %d addresses",
+                    remote_peer_id,
+                    len(our_addrs),
+                )
+
+                # Wait for SYNC message
+                with trio.fail_after(STREAM_READ_TIMEOUT):
+                    sync_bytes = await stream.read(MAX_MESSAGE_SIZE)
+
+                # Parse the SYNC message
+                sync_msg = HolePunch()
+                sync_msg.ParseFromString(sync_bytes)
+
+                # Verify it's a SYNC message
+                if sync_msg.type != HolePunch.SYNC:
+                    logger.warning("Expected SYNC message, got %s", sync_msg.type)
+                    await stream.close()
+                    return
+
+                logger.debug("Received SYNC message from %s", remote_peer_id)
+
+                # Perform hole punch
+                success = await self._perform_hole_punch(remote_peer_id, peer_addrs)
+
+                if success:
+                    logger.info(
+                        "Successfully established direct connection with %s",
+                        remote_peer_id,
+                    )
+                else:
+                    logger.warning(
+                        "Failed to establish direct connection with %s", remote_peer_id
+                    )
+
+            except trio.TooSlowError:
+                logger.warning("Timeout in DCUtR protocol with peer %s", remote_peer_id)
+            except Exception as e:
+                logger.error(
+                    "Error in DCUtR protocol with peer %s: %s", remote_peer_id, str(e)
+                )
+            finally:
+                # Clean up
+                self._in_progress.discard(remote_peer_id)
+                await stream.close()
+
+        except Exception as e:
+            logger.error("Error handling DCUtR stream: %s", str(e))
+            await stream.close()
+
+    async def initiate_hole_punch(self, peer_id: ID) -> bool:
+        """
+        Initiate a hole punch with a peer.
+
+        Parameters
+        ----------
+        peer_id : ID
+            The peer to hole punch with
+
+        Returns
+        -------
+        bool
+            True if hole punch was successful, False otherwise
+
+        """
+        # Check if we already have a direct connection
+        if await self._have_direct_connection(peer_id):
+            logger.debug("Already have direct connection to %s", peer_id)
+            return True
+
+        # Check if there's already an active hole punch attempt
+        if peer_id in self._in_progress:
+            logger.debug("Hole punch already in progress with %s", peer_id)
+            return False
+
+        # Check if we've exceeded the maximum number of attempts
+        attempts = self._hole_punch_attempts.get(peer_id, 0)
+        if attempts >= MAX_HOLE_PUNCH_ATTEMPTS:
+            logger.warning("Maximum hole punch attempts reached for peer %s", peer_id)
+            return False
+
+        # Mark as in progress and increment attempt counter
+        self._in_progress.add(peer_id)
+        self._hole_punch_attempts[peer_id] = attempts + 1
+
+        try:
+            # Open a DCUtR stream to the peer
+            logger.debug("Opening DCUtR stream to peer %s", peer_id)
+            stream = await self.host.new_stream(peer_id, [PROTOCOL_ID])
+            if not stream:
+                logger.warning("Failed to open DCUtR stream to peer %s", peer_id)
+                return False
+
+            try:
+                # Send our CONNECT message with our observed addresses
+                our_addrs = await self._get_observed_addrs()
+                connect_msg = HolePunch()
+                connect_msg.type = HolePunch.CONNECT
+                connect_msg.ObsAddrs.extend(our_addrs)
+
+                start_time = time.time()
+                with trio.fail_after(STREAM_WRITE_TIMEOUT):
+                    await stream.write(connect_msg.SerializeToString())
+
+                logger.debug(
+                    "Sent CONNECT message to %s with %d addresses",
+                    peer_id,
+                    len(our_addrs),
+                )
+
+                # Receive the peer's CONNECT message
+                with trio.fail_after(STREAM_READ_TIMEOUT):
+                    resp_bytes = await stream.read(MAX_MESSAGE_SIZE)
+
+                # Calculate RTT
+                rtt = time.time() - start_time
+
+                # Parse the response
+                resp = HolePunch()
+                resp.ParseFromString(resp_bytes)
+
+                # Verify it's a CONNECT message
+                if resp.type != HolePunch.CONNECT:
+                    logger.warning("Expected CONNECT message, got %s", resp.type)
+                    return False
+
+                logger.debug(
+                    "Received CONNECT response from %s with %d addresses",
+                    peer_id,
+                    len(resp.ObsAddrs),
+                )
+
+                # Process observed addresses from the peer
+                peer_addrs = self._decode_observed_addrs(list(resp.ObsAddrs))
+                logger.debug("Decoded %d valid addresses from peer", len(peer_addrs))
+
+                # Store the addresses in the peerstore
+                if peer_addrs:
+                    self.host.get_peerstore().add_addrs(
+                        peer_id, peer_addrs, 10 * 60
+                    )  # 10 minute TTL
+
+                # Send SYNC message with timing information
+                # We'll use a future time that's 2*RTT from now to ensure both sides
+                # are ready
+                punch_time = time.time() + (2 * rtt) + 1  # Add 1 second buffer
+
+                sync_msg = HolePunch()
+                sync_msg.type = HolePunch.SYNC
+
+                with trio.fail_after(STREAM_WRITE_TIMEOUT):
+                    await stream.write(sync_msg.SerializeToString())
+
+                logger.debug("Sent SYNC message to %s", peer_id)
+
+                # Perform the synchronized hole punch
+                success = await self._perform_hole_punch(
+                    peer_id, peer_addrs, punch_time
+                )
+
+                if success:
+                    logger.info(
+                        "Successfully established direct connection with %s", peer_id
+                    )
+                    return True
+                else:
+                    logger.warning(
+                        "Failed to establish direct connection with %s", peer_id
+                    )
+                    return False
+
+            except trio.TooSlowError:
+                logger.warning("Timeout in DCUtR protocol with peer %s", peer_id)
+                return False
+            except Exception as e:
+                logger.error(
+                    "Error in DCUtR protocol with peer %s: %s", peer_id, str(e)
+                )
+                return False
+            finally:
+                await stream.close()
+
+        except Exception as e:
+            logger.error(
+                "Error initiating hole punch with peer %s: %s", peer_id, str(e)
+            )
+            return False
+        finally:
+            self._in_progress.discard(peer_id)
+
+        # This should never be reached, but add explicit return for type checking
+        return False
+
+    async def _perform_hole_punch(
+        self, peer_id: ID, addrs: list[Multiaddr], punch_time: float | None = None
+    ) -> bool:
+        """
+        Perform a hole punch attempt with a peer.
+
+        Parameters
+        ----------
+        peer_id : ID
+            The peer to hole punch with
+        addrs : list[Multiaddr]
+            List of addresses to try
+        punch_time : Optional[float]
+            Time to perform the punch (if None, do it immediately)
+
+        Returns
+        -------
+        bool
+            True if hole punch was successful
+
+        """
+        if not addrs:
+            logger.warning("No addresses to try for hole punch with %s", peer_id)
+            return False
+
+        # If punch_time is specified, wait until that time
+        if punch_time is not None:
+            now = time.time()
+            if punch_time > now:
+                wait_time = punch_time - now
+                logger.debug("Waiting %.2f seconds before hole punch", wait_time)
+                await trio.sleep(wait_time)
+
+        # Try to dial each address
+        logger.debug(
+            "Starting hole punch with peer %s using %d addresses", peer_id, len(addrs)
+        )
+
+        # Filter to only include non-relay addresses
+        direct_addrs = [
+            addr for addr in addrs if not str(addr).startswith("/p2p-circuit")
+        ]
+
+        if not direct_addrs:
+            logger.warning("No direct addresses found for peer %s", peer_id)
+            return False
+
+        # Start dialing attempts in parallel
+        async with trio.open_nursery() as nursery:
+            for addr in direct_addrs[
+                :5
+            ]:  # Limit to 5 addresses to avoid too many connections
+                nursery.start_soon(self._dial_peer, peer_id, addr)
+
+        # Check if we established a direct connection
+        return await self._have_direct_connection(peer_id)
+
+    async def _dial_peer(self, peer_id: ID, addr: Multiaddr) -> None:
+        """
+        Attempt to dial a peer at a specific address.
+
+        Parameters
+        ----------
+        peer_id : ID
+            The peer to dial
+        addr : Multiaddr
+            The address to dial
+
+        """
+        try:
+            logger.debug("Attempting to dial %s at %s", peer_id, addr)
+
+            # Create peer info
+            peer_info = PeerInfo(peer_id, [addr])
+
+            # Try to connect with timeout
+            with trio.fail_after(DIAL_TIMEOUT):
+                await self.host.connect(peer_info)
+
+            logger.info("Successfully connected to %s at %s", peer_id, addr)
+
+            # Add to direct connections set
+            self._direct_connections.add(peer_id)
+
+        except trio.TooSlowError:
+            logger.debug("Timeout dialing %s at %s", peer_id, addr)
+        except Exception as e:
+            logger.debug("Error dialing %s at %s: %s", peer_id, addr, str(e))
+
+    async def _have_direct_connection(self, peer_id: ID) -> bool:
+        """
+        Check if we already have a direct connection to a peer.
+
+        Parameters
+        ----------
+        peer_id : ID
+            The peer to check
+
+        Returns
+        -------
+        bool
+            True if we have a direct connection, False otherwise
+
+        """
+        # Check our direct connections cache first
+        if peer_id in self._direct_connections:
+            return True
+
+        # Check if the peer is connected
+        network = self.host.get_network()
+        conn_or_conns = network.connections.get(peer_id)
+        if not conn_or_conns:
+            return False
+
+        # Handle both single connection and list of connections
+        connections: list[INetConn] = (
+            [conn_or_conns] if not isinstance(conn_or_conns, list) else conn_or_conns
+        )
+
+        # Check if any connection is direct (not relayed)
+        for conn in connections:
+            # Get the transport addresses
+            addrs = conn.get_transport_addresses()
+
+            # If any address doesn't start with /p2p-circuit, it's a direct connection
+            if any(not str(addr).startswith("/p2p-circuit") for addr in addrs):
+                # Cache this result
+                self._direct_connections.add(peer_id)
+                return True
+
+        return False
+
+    async def _get_observed_addrs(self) -> list[bytes]:
+        """
+        Get our observed addresses to share with the peer.
+
+        Returns
+        -------
+        List[bytes]
+            List of observed addresses as bytes
+
+        """
+        # Get all listen addresses
+        addrs = self.host.get_addrs()
+
+        # Filter out relay addresses
+        direct_addrs = [
+            addr for addr in addrs if not str(addr).startswith("/p2p-circuit")
+        ]
+
+        # Limit the number of addresses
+        if len(direct_addrs) > MAX_OBSERVED_ADDRS:
+            direct_addrs = direct_addrs[:MAX_OBSERVED_ADDRS]
+
+        # Convert to bytes
+        addr_bytes = [addr.to_bytes() for addr in direct_addrs]
+
+        return addr_bytes
+
+    def _decode_observed_addrs(self, addr_bytes: list[bytes]) -> list[Multiaddr]:
+        """
+        Decode observed addresses received from a peer.
+
+        Parameters
+        ----------
+        addr_bytes : List[bytes]
+            The encoded addresses
+
+        Returns
+        -------
+        List[Multiaddr]
+            The decoded multiaddresses
+
+        """
+        result = []
+
+        for addr_byte in addr_bytes:
+            try:
+                addr = Multiaddr(addr_byte)
+                # Validate the address (basic check)
+                if str(addr).startswith("/ip"):
+                    result.append(addr)
+            except Exception as e:
+                logger.debug("Error decoding multiaddr: %s", str(e))
+
+        return result

libp2p/relay/circuit_v2/discovery.py

@@ -234,7 +234,8 @@ class RelayDiscovery(Service):
 
             if not callable(proto_getter):
                 return None
-
+            if peer_id not in peerstore.peer_ids():
+                return None
             try:
                 # Try to get protocols
                 proto_result = proto_getter(peer_id)
@@ -283,8 +284,6 @@ class RelayDiscovery(Service):
                 return None
 
             mux = self.host.get_mux()
-            if not hasattr(mux, "protocols"):
-                return None
 
             peer_protocols = set()
             # Get protocols from mux with proper type safety
@@ -293,7 +292,9 @@ class RelayDiscovery(Service):
                 # Get protocols with proper typing
                 mux_protocols = mux.get_protocols()
                 if isinstance(mux_protocols, (list, tuple)):
-                    available_protocols = list(mux_protocols)
+                    available_protocols = [
+                        p for p in mux.get_protocols() if p is not None
+                    ]
 
             for protocol in available_protocols:
                 try:
@@ -313,7 +314,7 @@ class RelayDiscovery(Service):
 
             self._protocol_cache[peer_id] = peer_protocols
             protocol_str = str(PROTOCOL_ID)
-            for protocol in peer_protocols:
+            for protocol in map(TProtocol, peer_protocols):
                 if protocol == protocol_str:
                     return True
             return False

libp2p/relay/circuit_v2/nat.py

@@ -0,0 +1,300 @@
+"""
+NAT traversal utilities for libp2p.
+
+This module provides utilities for NAT traversal and reachability detection.
+"""
+
+import ipaddress
+import logging
+
+from multiaddr import (
+    Multiaddr,
+)
+
+from libp2p.abc import (
+    IHost,
+    INetConn,
+)
+from libp2p.peer.id import (
+    ID,
+)
+
+logger = logging.getLogger("libp2p.relay.circuit_v2.nat")
+
+# Timeout for reachability checks
+REACHABILITY_TIMEOUT = 10  # seconds
+
+# Define private IP ranges
+PRIVATE_IP_RANGES = [
+    ("10.0.0.0", "10.255.255.255"),  # Class A private network: 10.0.0.0/8
+    ("172.16.0.0", "172.31.255.255"),  # Class B private network: 172.16.0.0/12
+    ("192.168.0.0", "192.168.255.255"),  # Class C private network: 192.168.0.0/16
+]
+
+# Link-local address range: 169.254.0.0/16
+LINK_LOCAL_RANGE = ("169.254.0.0", "169.254.255.255")
+
+# Loopback address range: 127.0.0.0/8
+LOOPBACK_RANGE = ("127.0.0.0", "127.255.255.255")
+
+
+def ip_to_int(ip: str) -> int:
+    """
+    Convert an IP address to an integer.
+
+    Parameters
+    ----------
+    ip : str
+        IP address to convert
+
+    Returns
+    -------
+    int
+        Integer representation of the IP
+
+    """
+    try:
+        return int(ipaddress.IPv4Address(ip))
+    except ipaddress.AddressValueError:
+        # Handle IPv6 addresses
+        return int(ipaddress.IPv6Address(ip))
+
+
+def is_ip_in_range(ip: str, start_range: str, end_range: str) -> bool:
+    """
+    Check if an IP address is within a range.
+
+    Parameters
+    ----------
+    ip : str
+        IP address to check
+    start_range : str
+        Start of the range
+    end_range : str
+        End of the range
+
+    Returns
+    -------
+    bool
+        True if the IP is in the range
+
+    """
+    try:
+        ip_int = ip_to_int(ip)
+        start_int = ip_to_int(start_range)
+        end_int = ip_to_int(end_range)
+        return start_int <= ip_int <= end_int
+    except Exception:
+        return False
+
+
+def is_private_ip(ip: str) -> bool:
+    """
+    Check if an IP address is private.
+
+    Parameters
+    ----------
+    ip : str
+        IP address to check
+
+    Returns
+    -------
+    bool
+        True if IP is private
+
+    """
+    for start_range, end_range in PRIVATE_IP_RANGES:
+        if is_ip_in_range(ip, start_range, end_range):
+            return True
+
+    # Check for link-local addresses
+    if is_ip_in_range(ip, *LINK_LOCAL_RANGE):
+        return True
+
+    # Check for loopback addresses
+    if is_ip_in_range(ip, *LOOPBACK_RANGE):
+        return True
+
+    return False
+
+
+def extract_ip_from_multiaddr(addr: Multiaddr) -> str | None:
+    """
+    Extract the IP address from a multiaddr.
+
+    Parameters
+    ----------
+    addr : Multiaddr
+        Multiaddr to extract from
+
+    Returns
+    -------
+    Optional[str]
+        IP address or None if not found
+
+    """
+    # Convert to string representation
+    addr_str = str(addr)
+
+    # Look for IPv4 address
+    ipv4_start = addr_str.find("/ip4/")
+    if ipv4_start != -1:
+        # Extract the IPv4 address
+        ipv4_end = addr_str.find("/", ipv4_start + 5)
+        if ipv4_end != -1:
+            return addr_str[ipv4_start + 5 : ipv4_end]
+
+    # Look for IPv6 address
+    ipv6_start = addr_str.find("/ip6/")
+    if ipv6_start != -1:
+        # Extract the IPv6 address
+        ipv6_end = addr_str.find("/", ipv6_start + 5)
+        if ipv6_end != -1:
+            return addr_str[ipv6_start + 5 : ipv6_end]
+
+    return None
+
+
+class ReachabilityChecker:
+    """
+    Utility class for checking peer reachability.
+
+    This class assesses whether a peer's addresses are likely
+    to be directly reachable or behind NAT.
+    """
+
+    def __init__(self, host: IHost):
+        """
+        Initialize the reachability checker.
+
+        Parameters
+        ----------
+        host : IHost
+            The libp2p host
+
+        """
+        self.host = host
+        self._peer_reachability: dict[ID, bool] = {}
+        self._known_public_peers: set[ID] = set()
+
+    def is_addr_public(self, addr: Multiaddr) -> bool:
+        """
+        Check if an address is likely to be publicly reachable.
+
+        Parameters
+        ----------
+        addr : Multiaddr
+            The multiaddr to check
+
+        Returns
+        -------
+        bool
+            True if address is likely public
+
+        """
+        # Extract the IP address
+        ip = extract_ip_from_multiaddr(addr)
+        if not ip:
+            return False
+
+        # Check if it's a private IP
+        return not is_private_ip(ip)
+
+    def get_public_addrs(self, addrs: list[Multiaddr]) -> list[Multiaddr]:
+        """
+        Filter a list of addresses to only include likely public ones.
+
+        Parameters
+        ----------
+        addrs : List[Multiaddr]
+            List of addresses to filter
+
+        Returns
+        -------
+        List[Multiaddr]
+            List of likely public addresses
+
+        """
+        return [addr for addr in addrs if self.is_addr_public(addr)]
+
+    async def check_peer_reachability(self, peer_id: ID) -> bool:
+        """
+        Check if a peer is directly reachable.
+
+        Parameters
+        ----------
+        peer_id : ID
+            The peer ID to check
+
+        Returns
+        -------
+        bool
+            True if peer is likely directly reachable
+
+        """
+        # Check if we already know
+        if peer_id in self._peer_reachability:
+            return self._peer_reachability[peer_id]
+
+        # Check if the peer is connected
+        network = self.host.get_network()
+        connections: INetConn | list[INetConn] | None = network.connections.get(peer_id)
+        if not connections:
+            # Not connected, can't determine reachability
+            return False
+
+        # Check if any connection is direct (not relayed)
+        if isinstance(connections, list):
+            for conn in connections:
+                # Get the transport addresses
+                addrs = conn.get_transport_addresses()
+
+                # If any address doesn't start with /p2p-circuit,
+                # it's a direct connection
+                if any(not str(addr).startswith("/p2p-circuit") for addr in addrs):
+                    self._peer_reachability[peer_id] = True
+                    return True
+        else:
+            # Handle single connection case
+            addrs = connections.get_transport_addresses()
+            if any(not str(addr).startswith("/p2p-circuit") for addr in addrs):
+                self._peer_reachability[peer_id] = True
+                return True
+
+        # Get the peer's addresses from peerstore
+        try:
+            addrs = self.host.get_peerstore().addrs(peer_id)
+            # Check if peer has any public addresses
+            public_addrs = self.get_public_addrs(addrs)
+            if public_addrs:
+                self._peer_reachability[peer_id] = True
+                return True
+        except Exception as e:
+            logger.debug("Error getting peer addresses: %s", str(e))
+
+        # Default to not directly reachable
+        self._peer_reachability[peer_id] = False
+        return False
+
+    async def check_self_reachability(self) -> tuple[bool, list[Multiaddr]]:
+        """
+        Check if this host is likely directly reachable.
+
+        Returns
+        -------
+        Tuple[bool, List[Multiaddr]]
+            Tuple of (is_reachable, public_addresses)
+
+        """
+        # Get all host addresses
+        addrs = self.host.get_addrs()
+
+        # Filter for public addresses
+        public_addrs = self.get_public_addrs(addrs)
+
+        # If we have public addresses, assume we're reachable
+        # This is a simplified assumption - real reachability would need
+        # external checking
+        is_reachable = len(public_addrs) > 0
+
+        return is_reachable, public_addrs

libp2p/relay/circuit_v2/pb/__init__.py

@@ -5,6 +5,11 @@ Contains generated protobuf code for circuit_v2 relay protocol.
 """
 
 # Import the classes to be accessible directly from the package
+
+from .dcutr_pb2 import (
+    HolePunch,
+)
+
 from .circuit_pb2 import (
     HopMessage,
     Limit,
@@ -13,4 +18,4 @@ from .circuit_pb2 import (
     StopMessage,
 )
 
-__all__ = ["HopMessage", "Limit", "Reservation", "Status", "StopMessage"]
+__all__ = ["HopMessage", "Limit", "Reservation", "Status", "StopMessage", "HolePunch"]

libp2p/relay/circuit_v2/pb/circuit_pb2.py

@@ -1,6 +1,5 @@
 # -*- coding: utf-8 -*-
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
-# NO CHECKED-IN PROTOBUF GENCODE
 # source: libp2p/relay/circuit_v2/pb/circuit.proto
 """Generated protocol buffer code."""
 from google.protobuf.internal import builder as _builder
@@ -12,11 +11,14 @@ from google.protobuf import symbol_database as _symbol_database
 _sym_db = _symbol_database.Default()
 
 
+
+
 DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n(libp2p/relay/circuit_v2/pb/circuit.proto\x12\rcircuit.pb.v2\"\xf3\x01\n\nHopMessage\x12,\n\x04type\x18\x01 \x01(\x0e\x32\x1e.circuit.pb.v2.HopMessage.Type\x12\x0c\n\x04peer\x18\x02 \x01(\x0c\x12/\n\x0breservation\x18\x03 \x01(\x0b\x32\x1a.circuit.pb.v2.Reservation\x12#\n\x05limit\x18\x04 \x01(\x0b\x32\x14.circuit.pb.v2.Limit\x12%\n\x06status\x18\x05 \x01(\x0b\x32\x15.circuit.pb.v2.Status\",\n\x04Type\x12\x0b\n\x07RESERVE\x10\x00\x12\x0b\n\x07\x43ONNECT\x10\x01\x12\n\n\x06STATUS\x10\x02\"\x92\x01\n\x0bStopMessage\x12-\n\x04type\x18\x01 \x01(\x0e\x32\x1f.circuit.pb.v2.StopMessage.Type\x12\x0c\n\x04peer\x18\x02 \x01(\x0c\x12%\n\x06status\x18\x03 \x01(\x0b\x32\x15.circuit.pb.v2.Status\"\x1f\n\x04Type\x12\x0b\n\x07\x43ONNECT\x10\x00\x12\n\n\x06STATUS\x10\x01\"A\n\x0bReservation\x12\x0f\n\x07voucher\x18\x01 \x01(\x0c\x12\x11\n\tsignature\x18\x02 \x01(\x0c\x12\x0e\n\x06\x65xpire\x18\x03 \x01(\x03\"\'\n\x05Limit\x12\x10\n\x08\x64uration\x18\x01 \x01(\x03\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x03\"\xf6\x01\n\x06Status\x12(\n\x04\x63ode\x18\x01 \x01(\x0e\x32\x1a.circuit.pb.v2.Status.Code\x12\x0f\n\x07message\x18\x02 \x01(\t\"\xb0\x01\n\x04\x43ode\x12\x06\n\x02OK\x10\x00\x12\x17\n\x13RESERVATION_REFUSED\x10\x64\x12\x1b\n\x17RESOURCE_LIMIT_EXCEEDED\x10\x65\x12\x15\n\x11PERMISSION_DENIED\x10\x66\x12\x16\n\x11\x43ONNECTION_FAILED\x10\xc8\x01\x12\x11\n\x0c\x44IAL_REFUSED\x10\xc9\x01\x12\x10\n\x0bSTOP_FAILED\x10\xac\x02\x12\x16\n\x11MALFORMED_MESSAGE\x10\x90\x03\x62\x06proto3')
 
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
 _builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.relay.circuit_v2.pb.circuit_pb2', globals())
 if _descriptor._USE_C_DESCRIPTORS == False:
+
   DESCRIPTOR._options = None
   _HOPMESSAGE._serialized_start=60
   _HOPMESSAGE._serialized_end=303

libp2p/relay/circuit_v2/pb/dcutr.proto

@@ -0,0 +1,14 @@
+syntax = "proto2";
+
+package holepunch.pb;
+
+message HolePunch {
+  enum Type {
+    CONNECT = 100;
+    SYNC = 300;
+  }
+
+  required Type type = 1;
+
+  repeated bytes ObsAddrs = 2;
+}

libp2p/relay/circuit_v2/pb/dcutr_pb2.py

@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: libp2p/relay/circuit_v2/pb/dcutr.proto
+"""Generated protocol buffer code."""
+from google.protobuf.internal import builder as _builder
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import descriptor_pool as _descriptor_pool
+from google.protobuf import symbol_database as _symbol_database
+# @@protoc_insertion_point(imports)
+
+_sym_db = _symbol_database.Default()
+
+
+
+
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n&libp2p/relay/circuit_v2/pb/dcutr.proto\x12\x0cholepunch.pb\"i\n\tHolePunch\x12*\n\x04type\x18\x01 \x02(\x0e\x32\x1c.holepunch.pb.HolePunch.Type\x12\x10\n\x08ObsAddrs\x18\x02 \x03(\x0c\"\x1e\n\x04Type\x12\x0b\n\x07\x43ONNECT\x10\x64\x12\t\n\x04SYNC\x10\xac\x02')
+
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'libp2p.relay.circuit_v2.pb.dcutr_pb2', globals())
+if _descriptor._USE_C_DESCRIPTORS == False:
+
+  DESCRIPTOR._options = None
+  _HOLEPUNCH._serialized_start=56
+  _HOLEPUNCH._serialized_end=161
+  _HOLEPUNCH_TYPE._serialized_start=131
+  _HOLEPUNCH_TYPE._serialized_end=161
+# @@protoc_insertion_point(module_scope)

libp2p/relay/circuit_v2/pb/dcutr_pb2.pyi

@@ -0,0 +1,53 @@
+"""
+@generated by mypy-protobuf.  Do not edit manually!
+isort:skip_file
+"""
+
+import builtins
+import collections.abc
+import google.protobuf.descriptor
+import google.protobuf.internal.containers
+import google.protobuf.internal.enum_type_wrapper
+import google.protobuf.message
+import sys
+import typing
+
+if sys.version_info >= (3, 10):
+    import typing as typing_extensions
+else:
+    import typing_extensions
+
+DESCRIPTOR: google.protobuf.descriptor.FileDescriptor
+
+@typing.final
+class HolePunch(google.protobuf.message.Message):
+    DESCRIPTOR: google.protobuf.descriptor.Descriptor
+
+    class _Type:
+        ValueType = typing.NewType("ValueType", builtins.int)
+        V: typing_extensions.TypeAlias = ValueType
+
+    class _TypeEnumTypeWrapper(google.protobuf.internal.enum_type_wrapper._EnumTypeWrapper[HolePunch._Type.ValueType], builtins.type):
+        DESCRIPTOR: google.protobuf.descriptor.EnumDescriptor
+        CONNECT: HolePunch._Type.ValueType  # 100
+        SYNC: HolePunch._Type.ValueType  # 300
+
+    class Type(_Type, metaclass=_TypeEnumTypeWrapper): ...
+    CONNECT: HolePunch.Type.ValueType  # 100
+    SYNC: HolePunch.Type.ValueType  # 300
+
+    TYPE_FIELD_NUMBER: builtins.int
+    OBSADDRS_FIELD_NUMBER: builtins.int
+    type: global___HolePunch.Type.ValueType
+    @property
+    def ObsAddrs(self) -> google.protobuf.internal.containers.RepeatedScalarFieldContainer[builtins.bytes]: ...
+    def __init__(
+        self,
+        *,
+        type: global___HolePunch.Type.ValueType | None = ...,
+        ObsAddrs: collections.abc.Iterable[builtins.bytes] | None = ...,
+    ) -> None: ...
+    def HasField(self, field_name: typing.Literal["type", b"type"]) -> builtins.bool: ...
+    def ClearField(self, field_name: typing.Literal["ObsAddrs", b"ObsAddrs", "type", b"type"]) -> None: ...
+
+global___HolePunch = HolePunch

libp2p/security/noise/io.py

@@ -41,7 +41,8 @@ class BaseNoiseMsgReadWriter(EncryptedMsgReadWriter):
     read_writer: NoisePacketReadWriter
     noise_state: NoiseState
 
-    # FIXME: This prefix is added in msg#3 in Go. Check whether it's a desired behavior.
+    # NOTE: This prefix is added in msg#3 in Go.
+    #       Support in py-libp2p is available but not used
     prefix: bytes = b"\x00" * 32
 
     def __init__(self, conn: IRawConnection, noise_state: NoiseState) -> None:

libp2p/security/noise/transport.py

@@ -29,11 +29,6 @@ class Transport(ISecureTransport):
     early_data: bytes | None
     with_noise_pipes: bool
 
-    # NOTE: Implementations that support Noise Pipes must decide whether to use
-    #   an XX or IK handshake based on whether they possess a cached static
-    #   Noise key for the remote peer.
-    # TODO: A storage of seen noise static keys for pattern IK?
-
     def __init__(
         self,
         libp2p_keypair: KeyPair,

libp2p/stream_muxer/mplex/mplex_stream.py

@@ -1,3 +1,5 @@
+from collections.abc import AsyncGenerator
+from contextlib import asynccontextmanager
 from types import (
     TracebackType,
 )
@@ -32,6 +34,72 @@ if TYPE_CHECKING:
     )
 
 
+class ReadWriteLock:
+    """
+    A read-write lock that allows multiple concurrent readers
+    or one exclusive writer, implemented using Trio primitives.
+    """
+
+    def __init__(self) -> None:
+        self._readers = 0
+        self._readers_lock = trio.Lock()  # Protects access to _readers count
+        self._writer_lock = trio.Semaphore(1)  # Allows only one writer at a time
+
+    async def acquire_read(self) -> None:
+        """Acquire a read lock. Multiple readers can hold it simultaneously."""
+        try:
+            async with self._readers_lock:
+                if self._readers == 0:
+                    await self._writer_lock.acquire()
+                self._readers += 1
+        except trio.Cancelled:
+            raise
+
+    async def release_read(self) -> None:
+        """Release a read lock."""
+        async with self._readers_lock:
+            if self._readers == 1:
+                self._writer_lock.release()
+            self._readers -= 1
+
+    async def acquire_write(self) -> None:
+        """Acquire an exclusive write lock."""
+        try:
+            await self._writer_lock.acquire()
+        except trio.Cancelled:
+            raise
+
+    def release_write(self) -> None:
+        """Release the exclusive write lock."""
+        self._writer_lock.release()
+
+    @asynccontextmanager
+    async def read_lock(self) -> AsyncGenerator[None, None]:
+        """Context manager for acquiring and releasing a read lock safely."""
+        acquire = False
+        try:
+            await self.acquire_read()
+            acquire = True
+            yield
+        finally:
+            if acquire:
+                with trio.CancelScope() as scope:
+                    scope.shield = True
+                    await self.release_read()
+
+    @asynccontextmanager
+    async def write_lock(self) -> AsyncGenerator[None, None]:
+        """Context manager for acquiring and releasing a write lock safely."""
+        acquire = False
+        try:
+            await self.acquire_write()
+            acquire = True
+            yield
+        finally:
+            if acquire:
+                self.release_write()
+
+
 class MplexStream(IMuxedStream):
     """
     reference: https://github.com/libp2p/go-mplex/blob/master/stream.go
@@ -46,7 +114,7 @@ class MplexStream(IMuxedStream):
     read_deadline: int | None
     write_deadline: int | None
 
-    # TODO: Add lock for read/write to avoid interleaving receiving messages?
+    rw_lock: ReadWriteLock
     close_lock: trio.Lock
 
     # NOTE: `dataIn` is size of 8 in Go implementation.
@@ -80,6 +148,7 @@ class MplexStream(IMuxedStream):
         self.event_remote_closed = trio.Event()
         self.event_reset = trio.Event()
         self.close_lock = trio.Lock()
+        self.rw_lock = ReadWriteLock()
         self.incoming_data_channel = incoming_data_channel
         self._buf = bytearray()
 
@@ -113,48 +182,49 @@ class MplexStream(IMuxedStream):
         :param n: number of bytes to read
         :return: bytes actually read
         """
-        if n is not None and n < 0:
-            raise ValueError(
-                "the number of bytes to read `n` must be non-negative or "
-                f"`None` to indicate read until EOF, got n={n}"
-            )
-        if self.event_reset.is_set():
-            raise MplexStreamReset
-        if n is None:
-            return await self._read_until_eof()
-        if len(self._buf) == 0:
-            data: bytes
-            # Peek whether there is data available. If yes, we just read until there is
-            # no data, then return.
-            try:
-                data = self.incoming_data_channel.receive_nowait()
-                self._buf.extend(data)
-            except trio.EndOfChannel:
-                raise MplexStreamEOF
-            except trio.WouldBlock:
-                # We know `receive` will be blocked here. Wait for data here with
-                # `receive` and catch all kinds of errors here.
+        async with self.rw_lock.read_lock():
+            if n is not None and n < 0:
+                raise ValueError(
+                    "the number of bytes to read `n` must be non-negative or "
+                    f"`None` to indicate read until EOF, got n={n}"
+                )
+            if self.event_reset.is_set():
+                raise MplexStreamReset
+            if n is None:
+                return await self._read_until_eof()
+            if len(self._buf) == 0:
+                data: bytes
+                # Peek whether there is data available. If yes, we just read until
+                # there is no data, then return.
                 try:
-                    data = await self.incoming_data_channel.receive()
+                    data = self.incoming_data_channel.receive_nowait()
                     self._buf.extend(data)
                 except trio.EndOfChannel:
-                    if self.event_reset.is_set():
-                        raise MplexStreamReset
-                    if self.event_remote_closed.is_set():
-                        raise MplexStreamEOF
-                except trio.ClosedResourceError as error:
-                    # Probably `incoming_data_channel` is closed in `reset` when we are
-                    # waiting for `receive`.
-                    if self.event_reset.is_set():
-                        raise MplexStreamReset
-                    raise Exception(
-                        "`incoming_data_channel` is closed but stream is not reset. "
-                        "This should never happen."
-                    ) from error
-        self._buf.extend(self._read_return_when_blocked())
-        payload = self._buf[:n]
-        self._buf = self._buf[len(payload) :]
-        return bytes(payload)
+                    raise MplexStreamEOF
+                except trio.WouldBlock:
+                    # We know `receive` will be blocked here. Wait for data here with
+                    # `receive` and catch all kinds of errors here.
+                    try:
+                        data = await self.incoming_data_channel.receive()
+                        self._buf.extend(data)
+                    except trio.EndOfChannel:
+                        if self.event_reset.is_set():
+                            raise MplexStreamReset
+                        if self.event_remote_closed.is_set():
+                            raise MplexStreamEOF
+                    except trio.ClosedResourceError as error:
+                        # Probably `incoming_data_channel` is closed in `reset` when
+                        # we are waiting for `receive`.
+                        if self.event_reset.is_set():
+                            raise MplexStreamReset
+                        raise Exception(
+                            "`incoming_data_channel` is closed but stream is not reset."
+                            "This should never happen."
+                        ) from error
+            self._buf.extend(self._read_return_when_blocked())
+            payload = self._buf[:n]
+            self._buf = self._buf[len(payload) :]
+            return bytes(payload)
 
     async def write(self, data: bytes) -> None:
         """
@@ -162,22 +232,21 @@ class MplexStream(IMuxedStream):
 
         :return: number of bytes written
         """
-        if self.event_local_closed.is_set():
-            raise MplexStreamClosed(f"cannot write to closed stream: data={data!r}")
-        flag = (
-            HeaderTags.MessageInitiator
-            if self.is_initiator
-            else HeaderTags.MessageReceiver
-        )
-        await self.muxed_conn.send_message(flag, data, self.stream_id)
+        async with self.rw_lock.write_lock():
+            if self.event_local_closed.is_set():
+                raise MplexStreamClosed(f"cannot write to closed stream: data={data!r}")
+            flag = (
+                HeaderTags.MessageInitiator
+                if self.is_initiator
+                else HeaderTags.MessageReceiver
+            )
+            await self.muxed_conn.send_message(flag, data, self.stream_id)
 
     async def close(self) -> None:
         """
         Closing a stream closes it for writing and closes the remote end for
         reading but allows writing in the other direction.
         """
-        # TODO error handling with timeout
-
         async with self.close_lock:
             if self.event_local_closed.is_set():
                 return
@@ -185,8 +254,17 @@ class MplexStream(IMuxedStream):
         flag = (
             HeaderTags.CloseInitiator if self.is_initiator else HeaderTags.CloseReceiver
         )
-        # TODO: Raise when `muxed_conn.send_message` fails and `Mplex` isn't shutdown.
-        await self.muxed_conn.send_message(flag, None, self.stream_id)
+
+        try:
+            with trio.fail_after(5):  # timeout in seconds
+                await self.muxed_conn.send_message(flag, None, self.stream_id)
+        except trio.TooSlowError:
+            raise TimeoutError("Timeout while trying to close the stream")
+        except MuxedConnUnavailable:
+            if not self.muxed_conn.event_shutting_down.is_set():
+                raise RuntimeError(
+                    "Failed to send close message and Mplex isn't shutting down"
+                )
 
         _is_remote_closed: bool
         async with self.close_lock:

libp2p/stream_muxer/muxer_multistream.py

@@ -31,9 +31,6 @@ from libp2p.stream_muxer.yamux.yamux import (
     Yamux,
 )
 
-# FIXME: add negotiate timeout to `MuxerMultistream`
-DEFAULT_NEGOTIATE_TIMEOUT = 60
-
 
 class MuxerMultistream:
     """

libp2p/stream_muxer/yamux/yamux.py

@@ -45,6 +45,9 @@ from libp2p.stream_muxer.exceptions import (
     MuxedStreamReset,
 )
 
+# Configure logger for this module
+logger = logging.getLogger("libp2p.stream_muxer.yamux")
+
 PROTOCOL_ID = "/yamux/1.0.0"
 TYPE_DATA = 0x0
 TYPE_WINDOW_UPDATE = 0x1
@@ -98,16 +101,32 @@ class YamuxStream(IMuxedStream):
         # Flow control: Check if we have enough send window
         total_len = len(data)
         sent = 0
-
+        logger.debug(f"Stream {self.stream_id}: Starts writing {total_len} bytes ")
         while sent < total_len:
+            # Wait for available window with timeout
+            timeout = False
             async with self.window_lock:
-                # Wait for available window
-                while self.send_window == 0 and not self.closed:
-                    # Release lock while waiting
+                if self.send_window == 0:
+                    logger.debug(
+                        f"Stream {self.stream_id}: Window is zero, waiting for update"
+                    )
+                    # Release lock and wait with timeout
                     self.window_lock.release()
-                    await trio.sleep(0.01)
+                    # To avoid re-acquiring the lock immediately,
+                    with trio.move_on_after(5.0) as cancel_scope:
+                        while self.send_window == 0 and not self.closed:
+                            await trio.sleep(0.01)
+                        # If we timed out, cancel the scope
+                        timeout = cancel_scope.cancelled_caught
+                    # Re-acquire lock
                     await self.window_lock.acquire()
 
+                # If we timed out waiting for window update, raise an error
+                if timeout:
+                    raise MuxedStreamError(
+                        "Timed out waiting for window update after 5 seconds."
+                    )
+
                 if self.closed:
                     raise MuxedStreamError("Stream is closed")
 
@@ -123,25 +142,45 @@ class YamuxStream(IMuxedStream):
                 await self.conn.secured_conn.write(header + chunk)
                 sent += to_send
 
-        # If window is getting low, consider updating
-        if self.send_window < DEFAULT_WINDOW_SIZE // 2:
-            await self.send_window_update()
-
-    async def send_window_update(self, increment: int | None = None) -> None:
-        """Send a window update to peer."""
-        if increment is None:
-            increment = DEFAULT_WINDOW_SIZE - self.recv_window
+    async def send_window_update(self, increment: int, skip_lock: bool = False) -> None:
+        """
+        Send a window update to peer.
 
+        param:increment: The amount to increment the window size by.
+        If None, uses the difference between DEFAULT_WINDOW_SIZE
+        and current receive window.
+        param:skip_lock (bool): If True, skips acquiring window_lock.
+        This should only be used when calling from a context
+        that already holds the lock.
+        """
         if increment <= 0:
+            # If increment is zero or negative, skip sending update
+            logger.debug(
+                f"Stream {self.stream_id}: Skipping window update"
+                f"(increment={increment})"
+            )
             return
+        logger.debug(
+            f"Stream {self.stream_id}: Sending window update with increment={increment}"
+        )
 
-        async with self.window_lock:
-            self.recv_window += increment
+        async def _do_window_update() -> None:
             header = struct.pack(
-                YAMUX_HEADER_FORMAT, 0, TYPE_WINDOW_UPDATE, 0, self.stream_id, increment
+                YAMUX_HEADER_FORMAT,
+                0,
+                TYPE_WINDOW_UPDATE,
+                0,
+                self.stream_id,
+                increment,
             )
             await self.conn.secured_conn.write(header)
 
+        if skip_lock:
+            await _do_window_update()
+        else:
+            async with self.window_lock:
+                await _do_window_update()
+
     async def read(self, n: int | None = -1) -> bytes:
         # Handle None value for n by converting it to -1
         if n is None:
@@ -149,64 +188,77 @@ class YamuxStream(IMuxedStream):
 
         # If the stream is closed for receiving and the buffer is empty, raise EOF
         if self.recv_closed and not self.conn.stream_buffers.get(self.stream_id):
-            logging.debug(
+            logger.debug(
                 f"Stream {self.stream_id}: Stream closed for receiving and buffer empty"
             )
             raise MuxedStreamEOF("Stream is closed for receiving")
 
-        # If reading until EOF (n == -1), block until stream is closed
         if n == -1:
-            while not self.recv_closed and not self.conn.event_shutting_down.is_set():
+            data = b""
+            while not self.conn.event_shutting_down.is_set():
                 # Check if there's data in the buffer
                 buffer = self.conn.stream_buffers.get(self.stream_id)
-                if buffer and len(buffer) > 0:
-                    # Wait for closure even if data is available
-                    logging.debug(
-                        f"Stream {self.stream_id}:Waiting for FIN before returning data"
-                    )
-                    await self.conn.stream_events[self.stream_id].wait()
-                    self.conn.stream_events[self.stream_id] = trio.Event()
-                else:
-                    # No data, wait for data or closure
-                    logging.debug(f"Stream {self.stream_id}: Waiting for data or FIN")
-                    await self.conn.stream_events[self.stream_id].wait()
-                    self.conn.stream_events[self.stream_id] = trio.Event()
 
-            # After loop, check if stream is closed or shutting down
-            async with self.conn.streams_lock:
-                if self.conn.event_shutting_down.is_set():
-                    logging.debug(f"Stream {self.stream_id}: Connection shutting down")
-                    raise MuxedStreamEOF("Connection shut down")
-                if self.closed:
-                    if self.reset_received:
-                        logging.debug(f"Stream {self.stream_id}: Stream was reset")
-                        raise MuxedStreamReset("Stream was reset")
-                    else:
-                        logging.debug(
-                            f"Stream {self.stream_id}: Stream closed cleanly (EOF)"
-                        )
-                        raise MuxedStreamEOF("Stream closed cleanly (EOF)")
-                buffer = self.conn.stream_buffers.get(self.stream_id)
+                # If buffer is not available, check if stream is closed
                 if buffer is None:
-                    logging.debug(
-                        f"Stream {self.stream_id}: Buffer gone, assuming closed"
-                    )
+                    logger.debug(f"Stream {self.stream_id}: No buffer available")
                     raise MuxedStreamEOF("Stream buffer closed")
+
+                # If we have data in buffer, process it
+                if len(buffer) > 0:
+                    chunk = bytes(buffer)
+                    buffer.clear()
+                    data += chunk
+
+                    # Send window update for the chunk we just read
+                    async with self.window_lock:
+                        self.recv_window += len(chunk)
+                        logger.debug(f"Stream {self.stream_id}: Update {len(chunk)}")
+                        await self.send_window_update(len(chunk), skip_lock=True)
+
+                # If stream is closed (FIN received) and buffer is empty, break
                 if self.recv_closed and len(buffer) == 0:
-                    logging.debug(f"Stream {self.stream_id}: EOF reached")
-                    raise MuxedStreamEOF("Stream is closed for receiving")
-                # Return all buffered data
-                data = bytes(buffer)
-                buffer.clear()
-                logging.debug(f"Stream {self.stream_id}: Returning {len(data)} bytes")
+                    logger.debug(f"Stream {self.stream_id}: Closed with empty buffer")
+                    break
+
+                # If stream was reset, raise reset error
+                if self.reset_received:
+                    logger.debug(f"Stream {self.stream_id}: Stream was reset")
+                    raise MuxedStreamReset("Stream was reset")
+
+                # Wait for more data or stream closure
+                logger.debug(f"Stream {self.stream_id}: Waiting for data or FIN")
+                await self.conn.stream_events[self.stream_id].wait()
+                self.conn.stream_events[self.stream_id] = trio.Event()
+
+            # After loop exit, first check if we have data to return
+            if data:
+                logger.debug(
+                    f"Stream {self.stream_id}: Returning {len(data)} bytes after loop"
+                )
                 return data
 
-        # For specific size read (n > 0), return available data immediately
-        return await self.conn.read_stream(self.stream_id, n)
+            # No data accumulated, now check why we exited the loop
+            if self.conn.event_shutting_down.is_set():
+                logger.debug(f"Stream {self.stream_id}: Connection shutting down")
+                raise MuxedStreamEOF("Connection shut down")
+
+            # Return empty data
+            return b""
+        else:
+            data = await self.conn.read_stream(self.stream_id, n)
+            async with self.window_lock:
+                self.recv_window += len(data)
+                logger.debug(
+                    f"Stream {self.stream_id}: Sending window update after read, "
+                    f"increment={len(data)}"
+                )
+                await self.send_window_update(len(data), skip_lock=True)
+            return data
 
     async def close(self) -> None:
         if not self.send_closed:
-            logging.debug(f"Half-closing stream {self.stream_id} (local end)")
+            logger.debug(f"Half-closing stream {self.stream_id} (local end)")
             header = struct.pack(
                 YAMUX_HEADER_FORMAT, 0, TYPE_DATA, FLAG_FIN, self.stream_id, 0
             )
@@ -222,7 +274,7 @@ class YamuxStream(IMuxedStream):
 
     async def reset(self) -> None:
         if not self.closed:
-            logging.debug(f"Resetting stream {self.stream_id}")
+            logger.debug(f"Resetting stream {self.stream_id}")
             header = struct.pack(
                 YAMUX_HEADER_FORMAT, 0, TYPE_DATA, FLAG_RST, self.stream_id, 0
             )
@@ -300,7 +352,7 @@ class Yamux(IMuxedConn):
         self._nursery: Nursery | None = None
 
     async def start(self) -> None:
-        logging.debug(f"Starting Yamux for {self.peer_id}")
+        logger.debug(f"Starting Yamux for {self.peer_id}")
         if self.event_started.is_set():
             return
         async with trio.open_nursery() as nursery:
@@ -313,7 +365,7 @@ class Yamux(IMuxedConn):
         return self.is_initiator_value
 
     async def close(self, error_code: int = GO_AWAY_NORMAL) -> None:
-        logging.debug(f"Closing Yamux connection with code {error_code}")
+        logger.debug(f"Closing Yamux connection with code {error_code}")
         async with self.streams_lock:
             if not self.event_shutting_down.is_set():
                 try:
@@ -322,7 +374,7 @@ class Yamux(IMuxedConn):
                     )
                     await self.secured_conn.write(header)
                 except Exception as e:
-                    logging.debug(f"Failed to send GO_AWAY: {e}")
+                    logger.debug(f"Failed to send GO_AWAY: {e}")
                 self.event_shutting_down.set()
                 for stream in self.streams.values():
                     stream.closed = True
@@ -333,12 +385,12 @@ class Yamux(IMuxedConn):
                 self.stream_events.clear()
         try:
             await self.secured_conn.close()
-            logging.debug(f"Successfully closed secured_conn for peer {self.peer_id}")
+            logger.debug(f"Successfully closed secured_conn for peer {self.peer_id}")
         except Exception as e:
-            logging.debug(f"Error closing secured_conn for peer {self.peer_id}: {e}")
+            logger.debug(f"Error closing secured_conn for peer {self.peer_id}: {e}")
         self.event_closed.set()
         if self.on_close:
-            logging.debug(f"Calling on_close in Yamux.close for peer {self.peer_id}")
+            logger.debug(f"Calling on_close in Yamux.close for peer {self.peer_id}")
             if inspect.iscoroutinefunction(self.on_close):
                 if self.on_close is not None:
                     await self.on_close()
@@ -367,7 +419,7 @@ class Yamux(IMuxedConn):
             header = struct.pack(
                 YAMUX_HEADER_FORMAT, 0, TYPE_DATA, FLAG_SYN, stream_id, 0
             )
-            logging.debug(f"Sending SYN header for stream {stream_id}")
+            logger.debug(f"Sending SYN header for stream {stream_id}")
             await self.secured_conn.write(header)
             return stream
         except Exception as e:
@@ -375,32 +427,32 @@ class Yamux(IMuxedConn):
             raise e
 
     async def accept_stream(self) -> IMuxedStream:
-        logging.debug("Waiting for new stream")
+        logger.debug("Waiting for new stream")
         try:
             stream = await self.new_stream_receive_channel.receive()
-            logging.debug(f"Received stream {stream.stream_id}")
+            logger.debug(f"Received stream {stream.stream_id}")
             return stream
         except trio.EndOfChannel:
             raise MuxedStreamError("No new streams available")
 
     async def read_stream(self, stream_id: int, n: int = -1) -> bytes:
-        logging.debug(f"Reading from stream {self.peer_id}:{stream_id}, n={n}")
+        logger.debug(f"Reading from stream {self.peer_id}:{stream_id}, n={n}")
         if n is None:
             n = -1
 
         while True:
             async with self.streams_lock:
                 if stream_id not in self.streams:
-                    logging.debug(f"Stream {self.peer_id}:{stream_id} unknown")
+                    logger.debug(f"Stream {self.peer_id}:{stream_id} unknown")
                     raise MuxedStreamEOF("Stream closed")
                 if self.event_shutting_down.is_set():
-                    logging.debug(
+                    logger.debug(
                         f"Stream {self.peer_id}:{stream_id}: connection shutting down"
                     )
                     raise MuxedStreamEOF("Connection shut down")
                 stream = self.streams[stream_id]
                 buffer = self.stream_buffers.get(stream_id)
-                logging.debug(
+                logger.debug(
                     f"Stream {self.peer_id}:{stream_id}: "
                     f"closed={stream.closed}, "
                     f"recv_closed={stream.recv_closed}, "
@@ -408,7 +460,7 @@ class Yamux(IMuxedConn):
                     f"buffer_len={len(buffer) if buffer else 0}"
                 )
                 if buffer is None:
-                    logging.debug(
+                    logger.debug(
                         f"Stream {self.peer_id}:{stream_id}:"
                         f"Buffer gone, assuming closed"
                     )
@@ -421,7 +473,7 @@ class Yamux(IMuxedConn):
                     else:
                         data = bytes(buffer[:n])
                         del buffer[:n]
-                    logging.debug(
+                    logger.debug(
                         f"Returning {len(data)} bytes"
                         f"from stream {self.peer_id}:{stream_id}, "
                         f"buffer_len={len(buffer)}"
@@ -429,7 +481,7 @@ class Yamux(IMuxedConn):
                     return data
                 # If reset received and buffer is empty, raise reset
                 if stream.reset_received:
-                    logging.debug(
+                    logger.debug(
                         f"Stream {self.peer_id}:{stream_id}:"
                         f"reset_received=True, raising MuxedStreamReset"
                     )
@@ -442,7 +494,7 @@ class Yamux(IMuxedConn):
                     else:
                         data = bytes(buffer[:n])
                         del buffer[:n]
-                    logging.debug(
+                    logger.debug(
                         f"Returning {len(data)} bytes"
                         f"from stream {self.peer_id}:{stream_id}, "
                         f"buffer_len={len(buffer)}"
@@ -450,21 +502,21 @@ class Yamux(IMuxedConn):
                     return data
                 # Check if stream is closed
                 if stream.closed:
-                    logging.debug(
+                    logger.debug(
                         f"Stream {self.peer_id}:{stream_id}:"
                         f"closed=True, raising MuxedStreamReset"
                     )
                     raise MuxedStreamReset("Stream is reset or closed")
                 # Check if recv_closed and buffer empty
                 if stream.recv_closed:
-                    logging.debug(
+                    logger.debug(
                         f"Stream {self.peer_id}:{stream_id}:"
                         f"recv_closed=True, buffer empty, raising EOF"
                     )
                     raise MuxedStreamEOF("Stream is closed for receiving")
 
             # Wait for data if stream is still open
-            logging.debug(f"Waiting for data on stream {self.peer_id}:{stream_id}")
+            logger.debug(f"Waiting for data on stream {self.peer_id}:{stream_id}")
             try:
                 await self.stream_events[stream_id].wait()
                 self.stream_events[stream_id] = trio.Event()
@@ -479,7 +531,7 @@ class Yamux(IMuxedConn):
             try:
                 header = await self.secured_conn.read(HEADER_SIZE)
                 if not header or len(header) < HEADER_SIZE:
-                    logging.debug(
+                    logger.debug(
                         f"Connection closed orincomplete header for peer {self.peer_id}"
                     )
                     self.event_shutting_down.set()
@@ -488,12 +540,12 @@ class Yamux(IMuxedConn):
                 version, typ, flags, stream_id, length = struct.unpack(
                     YAMUX_HEADER_FORMAT, header
                 )
-                logging.debug(
+                logger.debug(
                     f"Received header for peer {self.peer_id}:"
                     f"type={typ}, flags={flags}, stream_id={stream_id},"
                     f"length={length}"
                 )
-                if typ == TYPE_DATA and flags & FLAG_SYN:
+                if (typ == TYPE_DATA or typ == TYPE_WINDOW_UPDATE) and flags & FLAG_SYN:
                     async with self.streams_lock:
                         if stream_id not in self.streams:
                             stream = YamuxStream(stream_id, self, False)
@@ -509,7 +561,7 @@ class Yamux(IMuxedConn):
                                 0,
                             )
                             await self.secured_conn.write(ack_header)
-                            logging.debug(
+                            logger.debug(
                                 f"Sending stream {stream_id}"
                                 f"to channel for peer {self.peer_id}"
                             )
@@ -527,7 +579,7 @@ class Yamux(IMuxedConn):
                 elif typ == TYPE_DATA and flags & FLAG_RST:
                     async with self.streams_lock:
                         if stream_id in self.streams:
-                            logging.debug(
+                            logger.debug(
                                 f"Resetting stream {stream_id} for peer {self.peer_id}"
                             )
                             self.streams[stream_id].closed = True
@@ -536,27 +588,27 @@ class Yamux(IMuxedConn):
                 elif typ == TYPE_DATA and flags & FLAG_ACK:
                     async with self.streams_lock:
                         if stream_id in self.streams:
-                            logging.debug(
+                            logger.debug(
                                 f"Received ACK for stream"
                                 f"{stream_id} for peer {self.peer_id}"
                             )
                 elif typ == TYPE_GO_AWAY:
                     error_code = length
                     if error_code == GO_AWAY_NORMAL:
-                        logging.debug(
+                        logger.debug(
                             f"Received GO_AWAY for peer"
                             f"{self.peer_id}: Normal termination"
                         )
                     elif error_code == GO_AWAY_PROTOCOL_ERROR:
-                        logging.error(
+                        logger.error(
                             f"Received GO_AWAY for peer{self.peer_id}: Protocol error"
                         )
                     elif error_code == GO_AWAY_INTERNAL_ERROR:
-                        logging.error(
+                        logger.error(
                             f"Received GO_AWAY for peer {self.peer_id}: Internal error"
                         )
                     else:
-                        logging.error(
+                        logger.error(
                             f"Received GO_AWAY for peer {self.peer_id}"
                             f"with unknown error code: {error_code}"
                         )
@@ -565,7 +617,7 @@ class Yamux(IMuxedConn):
                     break
                 elif typ == TYPE_PING:
                     if flags & FLAG_SYN:
-                        logging.debug(
+                        logger.debug(
                             f"Received ping request with value"
                             f"{length} for peer {self.peer_id}"
                         )
@@ -574,7 +626,7 @@ class Yamux(IMuxedConn):
                         )
                         await self.secured_conn.write(ping_header)
                     elif flags & FLAG_ACK:
-                        logging.debug(
+                        logger.debug(
                             f"Received ping response with value"
                             f"{length} for peer {self.peer_id}"
                         )
@@ -588,7 +640,7 @@ class Yamux(IMuxedConn):
                                 self.stream_buffers[stream_id].extend(data)
                                 self.stream_events[stream_id].set()
                                 if flags & FLAG_FIN:
-                                    logging.debug(
+                                    logger.debug(
                                         f"Received FIN for stream {self.peer_id}:"
                                         f"{stream_id}, marking recv_closed"
                                     )
@@ -596,7 +648,7 @@ class Yamux(IMuxedConn):
                                     if self.streams[stream_id].send_closed:
                                         self.streams[stream_id].closed = True
                     except Exception as e:
-                        logging.error(f"Error reading data for stream {stream_id}: {e}")
+                        logger.error(f"Error reading data for stream {stream_id}: {e}")
                         # Mark stream as closed on read error
                         async with self.streams_lock:
                             if stream_id in self.streams:
@@ -610,7 +662,7 @@ class Yamux(IMuxedConn):
                         if stream_id in self.streams:
                             stream = self.streams[stream_id]
                             async with stream.window_lock:
-                                logging.debug(
+                                logger.debug(
                                     f"Received window update for stream"
                                     f"{self.peer_id}:{stream_id},"
                                     f" increment: {increment}"
@@ -625,7 +677,7 @@ class Yamux(IMuxedConn):
                         and details.get("requested_count") == 2
                         and details.get("received_count") == 0
                     ):
-                        logging.info(
+                        logger.info(
                             f"Stream closed cleanly for peer {self.peer_id}"
                             + f" (IncompleteReadError: {details})"
                         )
@@ -633,15 +685,32 @@ class Yamux(IMuxedConn):
                         await self._cleanup_on_error()
                         break
                     else:
-                        logging.error(
+                        logger.error(
                             f"Error in handle_incoming for peer {self.peer_id}: "
                             + f"{type(e).__name__}: {str(e)}"
                         )
                 else:
-                    logging.error(
-                        f"Error in handle_incoming for peer {self.peer_id}: "
-                        + f"{type(e).__name__}: {str(e)}"
-                    )
+                    # Handle RawConnError with more nuance
+                    if isinstance(e, RawConnError):
+                        error_msg = str(e)
+                        # If RawConnError is empty, it's likely normal cleanup
+                        if not error_msg.strip():
+                            logger.info(
+                                f"RawConnError (empty) during cleanup for peer "
+                                f"{self.peer_id} (normal connection shutdown)"
+                            )
+                        else:
+                            # Log non-empty RawConnError as warning
+                            logger.warning(
+                                f"RawConnError during connection handling for peer "
+                                f"{self.peer_id}: {error_msg}"
+                            )
+                    else:
+                        # Log all other errors normally
+                        logger.error(
+                            f"Error in handle_incoming for peer {self.peer_id}: "
+                            + f"{type(e).__name__}: {str(e)}"
+                        )
                 # Don't crash the whole connection for temporary errors
                 if self.event_shutting_down.is_set() or isinstance(
                     e, (RawConnError, OSError)
@@ -671,9 +740,9 @@ class Yamux(IMuxedConn):
         # Close the secured connection
         try:
             await self.secured_conn.close()
-            logging.debug(f"Successfully closed secured_conn for peer {self.peer_id}")
+            logger.debug(f"Successfully closed secured_conn for peer {self.peer_id}")
         except Exception as close_error:
-            logging.error(
+            logger.error(
                 f"Error closing secured_conn for peer {self.peer_id}: {close_error}"
             )
 
@@ -682,14 +751,14 @@ class Yamux(IMuxedConn):
 
         # Call on_close callback if provided
         if self.on_close:
-            logging.debug(f"Calling on_close for peer {self.peer_id}")
+            logger.debug(f"Calling on_close for peer {self.peer_id}")
             try:
                 if inspect.iscoroutinefunction(self.on_close):
                     await self.on_close()
                 else:
                     self.on_close()
             except Exception as callback_error:
-                logging.error(f"Error in on_close callback: {callback_error}")
+                logger.error(f"Error in on_close callback: {callback_error}")
 
         # Cancel nursery tasks
         if self._nursery:

libp2p/utils/__init__.py

@@ -7,6 +7,9 @@ from libp2p.utils.varint import (
     encode_varint_prefixed,
     read_delim,
     read_varint_prefixed_bytes,
+    decode_varint_from_bytes,
+    decode_varint_with_size,
+    read_length_prefixed_protobuf,
 )
 from libp2p.utils.version import (
     get_agent_version,
@@ -20,4 +23,7 @@ __all__ = [
     "get_agent_version",
     "read_delim",
     "read_varint_prefixed_bytes",
+    "decode_varint_from_bytes",
+    "decode_varint_with_size",
+    "read_length_prefixed_protobuf",
 ]

libp2p/utils/varint.py

@@ -1,7 +1,9 @@
 import itertools
 import logging
 import math
+from typing import BinaryIO
 
+from libp2p.abc import INetStream
 from libp2p.exceptions import (
     ParseError,
 )
@@ -25,18 +27,41 @@ HIGH_MASK = 2**7
 SHIFT_64_BIT_MAX = int(math.ceil(64 / 7)) * 7
 
 
-def encode_uvarint(number: int) -> bytes:
-    """Pack `number` into varint bytes."""
-    buf = b""
-    while True:
-        towrite = number & 0x7F
-        number >>= 7
-        if number:
-            buf += bytes((towrite | 0x80,))
-        else:
-            buf += bytes((towrite,))
+def encode_uvarint(value: int) -> bytes:
+    """Encode an unsigned integer as a varint."""
+    if value < 0:
+        raise ValueError("Cannot encode negative value as uvarint")
+
+    result = bytearray()
+    while value >= 0x80:
+        result.append((value & 0x7F) | 0x80)
+        value >>= 7
+    result.append(value & 0x7F)
+    return bytes(result)
+
+
+def decode_uvarint(data: bytes) -> int:
+    """Decode a varint from bytes."""
+    if not data:
+        raise ParseError("Unexpected end of data")
+
+    result = 0
+    shift = 0
+
+    for byte in data:
+        result |= (byte & 0x7F) << shift
+        if (byte & 0x80) == 0:
             break
-    return buf
+        shift += 7
+        if shift >= 64:
+            raise ValueError("Varint too long")
+
+    return result
+
+
+def decode_varint_from_bytes(data: bytes) -> int:
+    """Decode a varint from bytes (alias for decode_uvarint for backward comp)."""
+    return decode_uvarint(data)
 
 
 async def decode_uvarint_from_stream(reader: Reader) -> int:
@@ -44,7 +69,9 @@ async def decode_uvarint_from_stream(reader: Reader) -> int:
     res = 0
     for shift in itertools.count(0, 7):
         if shift > SHIFT_64_BIT_MAX:
-            raise ParseError("TODO: better exception msg: Integer is too large...")
+            raise ParseError(
+                "Varint decoding error: integer exceeds maximum size of 64 bits."
+            )
 
         byte = await read_exactly(reader, 1)
         value = byte[0]
@@ -56,9 +83,35 @@ async def decode_uvarint_from_stream(reader: Reader) -> int:
     return res
 
 
-def encode_varint_prefixed(msg_bytes: bytes) -> bytes:
-    varint_len = encode_uvarint(len(msg_bytes))
-    return varint_len + msg_bytes
+def decode_varint_with_size(data: bytes) -> tuple[int, int]:
+    """
+    Decode a varint from bytes and return both the value and the number of bytes
+    consumed.
+
+    Returns:
+        Tuple[int, int]: (value, bytes_consumed)
+
+    """
+    result = 0
+    shift = 0
+    bytes_consumed = 0
+
+    for byte in data:
+        result |= (byte & 0x7F) << shift
+        bytes_consumed += 1
+        if (byte & 0x80) == 0:
+            break
+        shift += 7
+        if shift >= 64:
+            raise ValueError("Varint too long")
+
+    return result, bytes_consumed
+
+
+def encode_varint_prefixed(data: bytes) -> bytes:
+    """Encode data with a varint length prefix."""
+    length_bytes = encode_uvarint(len(data))
+    return length_bytes + data
 
 
 async def read_varint_prefixed_bytes(reader: Reader) -> bytes:
@@ -85,3 +138,95 @@ async def read_delim(reader: Reader) -> bytes:
             f'`msg_bytes` is not delimited by b"\\n": `msg_bytes`={msg_bytes!r}'
         )
     return msg_bytes[:-1]
+
+
+def read_varint_prefixed_bytes_sync(
+    stream: BinaryIO, max_length: int = 1024 * 1024
+) -> bytes:
+    """
+    Read varint-prefixed bytes from a stream.
+
+    Args:
+        stream: A stream-like object with a read() method
+        max_length: Maximum allowed data length to prevent memory exhaustion
+
+    Returns:
+        bytes: The data without the length prefix
+
+    Raises:
+        ValueError: If the length prefix is invalid or too large
+        EOFError: If the stream ends unexpectedly
+
+    """
+    # Read the varint length prefix
+    length_bytes = b""
+    while True:
+        byte_data = stream.read(1)
+        if not byte_data:
+            raise EOFError("Stream ended while reading varint length prefix")
+
+        length_bytes += byte_data
+        if byte_data[0] & 0x80 == 0:
+            break
+
+    # Decode the length
+    length = decode_uvarint(length_bytes)
+
+    if length > max_length:
+        raise ValueError(f"Data length {length} exceeds maximum allowed {max_length}")
+
+    # Read the data
+    data = stream.read(length)
+    if len(data) != length:
+        raise EOFError(f"Expected {length} bytes, got {len(data)}")
+
+    return data
+
+
+async def read_length_prefixed_protobuf(
+    stream: INetStream, use_varint_format: bool = True, max_length: int = 1024 * 1024
+) -> bytes:
+    """Read a protobuf message from a stream, handling both formats."""
+    if use_varint_format:
+        # Read length-prefixed protobuf message from the stream
+        # First read the varint length prefix
+        length_bytes = b""
+        while True:
+            b = await stream.read(1)
+            if not b:
+                raise Exception("No length prefix received")
+
+            length_bytes += b
+            if b[0] & 0x80 == 0:
+                break
+
+        msg_length = decode_varint_from_bytes(length_bytes)
+
+        if msg_length > max_length:
+            raise Exception(
+                f"Message length {msg_length} exceeds maximum allowed {max_length}"
+            )
+
+        # Read the protobuf message
+        data = await stream.read(msg_length)
+        if len(data) != msg_length:
+            raise Exception(
+                f"Incomplete message: expected {msg_length}, got {len(data)}"
+            )
+
+        return data
+    else:
+        # Read raw protobuf message from the stream
+        # For raw format, read all available data in one go
+        data = await stream.read()
+
+        # If we got no data, raise an exception
+        if not data:
+            raise Exception("No data received in raw format")
+
+        if len(data) > max_length:
+            raise Exception(
+                f"Message length {len(data)} exceeds maximum allowed {max_length}"
+            )
+
+        return data

newsfragments/579.feature.rst

@@ -1 +0,0 @@
-Added support for ``Kademlia DHT`` in py-libp2p.

newsfragments/592.internal.rst

@@ -0,0 +1 @@
+remove FIXME comment since it's obsolete and 32-byte prefix support is there but not enabled by default

newsfragments/631.feature.rst

@@ -1,7 +0,0 @@
-Store public key and peer ID in peerstore during handshake
-
-Modified the InsecureTransport class to accept an optional peerstore parameter and updated the handshake process to store the received public key and peer ID in the peerstore when available.
-
-Added test cases to verify:
-1. The peerstore remains unchanged when handshake fails due to peer ID mismatch
-2. The handshake correctly adds a public key to a peer ID that already exists in the peerstore but doesn't have a public key yet

newsfragments/678.misc.rst

@@ -1 +0,0 @@
-Refactored gossipsub heartbeat logic to use a single helper method `_handle_topic_heartbeat` that handles both fanout and gossip heartbeats.

newsfragments/679.feature.rst

@@ -1 +0,0 @@
-Added sparse connect utility function to pubsub test utilities for creating test networks with configurable connectivity.

newsfragments/681.breaking.rst

@@ -1,2 +0,0 @@
-Reordered the arguments to `upgrade_security` to place `is_initiator` before `peer_id`, and made `peer_id` optional.
-This allows the method to reflect the fact that peer identity is not required for inbound connections.

newsfragments/684.misc.rst

@@ -1 +0,0 @@
-Uses the `decapsulate` method of the `Multiaddr` class to clean up the observed address.

newsfragments/685.feature.rst

@@ -1 +0,0 @@
-Optimized pubsub publishing to send multiple topics in a single message instead of separate messages per topic.

newsfragments/690.feature.rst

@@ -1 +0,0 @@
-added peer exchange and backoff logic as part of Gossipsub v1.1 upgrade

newsfragments/711.feature.rst

@@ -0,0 +1 @@
+Added `Bootstrap` peer discovery module that allows nodes to connect to predefined bootstrap peers for network discovery.

newsfragments/746.bugfix.rst

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+Improved type safety in `get_mux()` and `get_protocols()` by returning properly typed values instead
+of `Any`. Also updated `identify.py` and `discovery.py` to handle `None` values safely and
+compare protocols correctly.

newsfragments/748.feature.rst

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+ Add lock for read/write to avoid interleaving receiving messages in mplex_stream.py

newsfragments/749.internal.rst

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+Add comprehensive tests for relay_discovery method in circuit_relay_v2

newsfragments/750.feature.rst

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+Add logic to clear_peerdata method in peerstore

newsfragments/752.internal.rst

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+[mplex] Add timeout and error handling during stream close