From: Valentine Wallace Date: Thu, 4 Aug 2022 15:05:07 +0000 (-0400) Subject: Refuse to send and forward OMs to disconnected peers X-Git-Tag: v0.0.111~20^2~2 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=b9b02b48fb4dd66181f61739fa0047c29dead697;p=rust-lightning Refuse to send and forward OMs to disconnected peers We also refuse to connect to peers that don't advertise onion message forwarding support. --- diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs index dbc17a341..c978c61a3 100644 --- a/lightning/src/ln/features.rs +++ b/lightning/src/ln/features.rs @@ -433,6 +433,11 @@ mod sealed { define_feature!(27, ShutdownAnySegwit, [InitContext, NodeContext], "Feature flags for `opt_shutdown_anysegwit`.", set_shutdown_any_segwit_optional, set_shutdown_any_segwit_required, supports_shutdown_anysegwit, requires_shutdown_anysegwit); + // We do not yet advertise the onion messages feature bit, but we need to detect when peers + // support it. + define_feature!(39, OnionMessages, [InitContext, NodeContext], + "Feature flags for `option_onion_messages`.", set_onion_messages_optional, + set_onion_messages_required, supports_onion_messages, requires_onion_messages); define_feature!(45, ChannelType, [InitContext, NodeContext], "Feature flags for `option_channel_type`.", set_channel_type_optional, set_channel_type_required, supports_channel_type, requires_channel_type); @@ -767,7 +772,7 @@ impl Features { impl Features { // We are no longer setting initial_routing_sync now that gossip_queries - // is enabled. This feature is ignored by a peer when gossip_queries has + // is enabled. This feature is ignored by a peer when gossip_queries has // been negotiated. #[cfg(test)] pub(crate) fn clear_initial_routing_sync(&mut self) { diff --git a/lightning/src/ln/msgs.rs b/lightning/src/ln/msgs.rs index 190907ce2..a32b17b9f 100644 --- a/lightning/src/ln/msgs.rs +++ b/lightning/src/ln/msgs.rs @@ -949,6 +949,12 @@ pub trait RoutingMessageHandler : MessageSendEventsProvider { pub trait OnionMessageHandler : OnionMessageProvider { /// Handle an incoming onion_message message from the given peer. fn handle_onion_message(&self, peer_node_id: &PublicKey, msg: &OnionMessage); + /// Called when a connection is established with a peer. Can be used to track which peers + /// advertise onion message support and are online. + fn peer_connected(&self, their_node_id: &PublicKey, init: &Init); + /// Indicates a connection to the peer failed/an existing connection was lost. Allows handlers to + /// drop and refuse to forward onion messages to this peer. + fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool); } mod fuzzy_internal_msgs { diff --git a/lightning/src/ln/peer_handler.rs b/lightning/src/ln/peer_handler.rs index 1258026e1..f80c8984c 100644 --- a/lightning/src/ln/peer_handler.rs +++ b/lightning/src/ln/peer_handler.rs @@ -81,6 +81,8 @@ impl OnionMessageProvider for IgnoringMessageHandler { } impl OnionMessageHandler for IgnoringMessageHandler { fn handle_onion_message(&self, _their_node_id: &PublicKey, _msg: &msgs::OnionMessage) {} + fn peer_connected(&self, _their_node_id: &PublicKey, _init: &msgs::Init) {} + fn peer_disconnected(&self, _their_node_id: &PublicKey, _no_connection_possible: bool) {} } impl Deref for IgnoringMessageHandler { type Target = IgnoringMessageHandler; @@ -1173,8 +1175,9 @@ impl Vec { - let mut res = Vec::new(); + let mut nodes = Vec::new(); for i in 0..num_messengers { let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i))); let seed = [i as u8; 32]; let keys_manager = Arc::new(test_utils::TestKeysInterface::new(&seed, Network::Testnet)); - res.push(MessengerNode { + nodes.push(MessengerNode { keys_manager: keys_manager.clone(), messenger: OnionMessenger::new(keys_manager, logger.clone()), logger, }); } - res + for idx in 0..num_messengers - 1 { + let i = idx as usize; + let mut features = InitFeatures::known(); + features.set_onion_messages_optional(); + let init_msg = msgs::Init { features, remote_network_address: None }; + nodes[i].messenger.peer_connected(&nodes[i + 1].get_node_pk(), &init_msg.clone()); + nodes[i + 1].messenger.peer_connected(&nodes[i].get_node_pk(), &init_msg.clone()); + } + nodes } fn pass_along_path(path: &Vec, expected_path_id: Option<[u8; 32]>) { @@ -53,7 +62,6 @@ fn pass_along_path(path: &Vec, expected_path_id: Option<[u8; 32]> let num_nodes = path.len(); for (idx, node) in path.into_iter().skip(1).enumerate() { let events = prev_node.messenger.release_pending_msgs(); - assert_eq!(events.len(), 1); let onion_msg = { let msgs = events.get(&node.get_node_pk()).unwrap(); assert_eq!(msgs.len(), 1); @@ -110,12 +118,9 @@ fn three_blinded_hops() { #[test] fn too_big_packet_error() { // Make sure we error as expected if a packet is too big to send. - let nodes = create_nodes(1); - - let hop_secret = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap(); - let secp_ctx = Secp256k1::new(); - let hop_node_id = PublicKey::from_secret_key(&secp_ctx, &hop_secret); + let nodes = create_nodes(2); + let hop_node_id = nodes[1].get_node_pk(); let hops = [hop_node_id; 400]; let err = nodes[0].messenger.send_onion_message(&hops, Destination::Node(hop_node_id), None).unwrap_err(); assert_eq!(err, SendError::TooBigPacket); diff --git a/lightning/src/onion_message/messenger.rs b/lightning/src/onion_message/messenger.rs index 3a14c78d0..b9da9246c 100644 --- a/lightning/src/onion_message/messenger.rs +++ b/lightning/src/onion_message/messenger.rs @@ -122,6 +122,8 @@ pub enum SendError { /// The provided [`Destination`] was an invalid [`BlindedRoute`], due to having fewer than two /// blinded hops. TooFewBlindedHops, + /// Our next-hop peer was offline or does not support onion message forwarding. + InvalidFirstHop, } impl OnionMessenger @@ -165,25 +167,28 @@ impl OnionMessenger .map_err(|e| SendError::Secp256k1(e))?; let prng_seed = self.keys_manager.get_secure_random_bytes(); - let onion_packet = construct_onion_message_packet( + let onion_routing_packet = construct_onion_message_packet( packet_payloads, packet_keys, prng_seed).map_err(|()| SendError::TooBigPacket)?; let mut pending_per_peer_msgs = self.pending_messages.lock().unwrap(); - let pending_msgs = pending_per_peer_msgs.entry(introduction_node_id).or_insert_with(VecDeque::new); - pending_msgs.push_back( - msgs::OnionMessage { - blinding_point, - onion_routing_packet: onion_packet, + match pending_per_peer_msgs.entry(introduction_node_id) { + hash_map::Entry::Vacant(_) => Err(SendError::InvalidFirstHop), + hash_map::Entry::Occupied(mut e) => { + e.get_mut().push_back(msgs::OnionMessage { blinding_point, onion_routing_packet }); + Ok(()) } - ); - Ok(()) + } } #[cfg(test)] pub(super) fn release_pending_msgs(&self) -> HashMap> { let mut pending_msgs = self.pending_messages.lock().unwrap(); let mut msgs = HashMap::new(); - core::mem::swap(&mut *pending_msgs, &mut msgs); + // We don't want to disconnect the peers by removing them entirely from the original map, so we + // swap the pending message buffers individually. + for (peer_node_id, pending_messages) in &mut *pending_msgs { + msgs.insert(*peer_node_id, core::mem::take(pending_messages)); + } msgs } } @@ -252,32 +257,43 @@ impl OnionMessageHandler for OnionMessenger blinding_point, - None => { - let blinding_factor = { - let mut sha = Sha256::engine(); - sha.input(&msg.blinding_point.serialize()[..]); - sha.input(control_tlvs_ss.as_ref()); - Sha256::from_engine(sha).into_inner() - }; - let next_blinding_point = msg.blinding_point; - match next_blinding_point.mul_tweak(&self.secp_ctx, &Scalar::from_be_bytes(blinding_factor).unwrap()) { - Ok(bp) => bp, - Err(e) => { - log_trace!(self.logger, "Failed to compute next blinding point: {}", e); - return - } - } - }, - }, - onion_routing_packet: outgoing_packet, + + #[cfg(fuzzing)] + pending_per_peer_msgs.entry(next_node_id).or_insert_with(VecDeque::new); + + match pending_per_peer_msgs.entry(next_node_id) { + hash_map::Entry::Vacant(_) => { + log_trace!(self.logger, "Dropping forwarded onion message to disconnected peer {:?}", next_node_id); + return }, - ); - log_trace!(self.logger, "Forwarding an onion message to peer {}", next_node_id); + hash_map::Entry::Occupied(mut e) => { + e.get_mut().push_back( + msgs::OnionMessage { + blinding_point: match next_blinding_override { + Some(blinding_point) => blinding_point, + None => { + let blinding_factor = { + let mut sha = Sha256::engine(); + sha.input(&msg.blinding_point.serialize()[..]); + sha.input(control_tlvs_ss.as_ref()); + Sha256::from_engine(sha).into_inner() + }; + let next_blinding_point = msg.blinding_point; + match next_blinding_point.mul_tweak(&self.secp_ctx, &Scalar::from_be_bytes(blinding_factor).unwrap()) { + Ok(bp) => bp, + Err(e) => { + log_trace!(self.logger, "Failed to compute next blinding point: {}", e); + return + } + } + }, + }, + onion_routing_packet: outgoing_packet, + }, + ); + log_trace!(self.logger, "Forwarding an onion message to peer {}", next_node_id); + } + }; }, Err(e) => { log_trace!(self.logger, "Errored decoding onion message packet: {:?}", e); @@ -287,6 +303,18 @@ impl OnionMessageHandler for OnionMessenger OnionMessageProvider for OnionMessenger