Merge pull request #1715 from TheBlueMatt/2022-09-fix-msg-send

Fix encryption of broadcasted gossip messages

diff --combined lightning/src/ln/peer_handler.rs
index aae602cfa30057ffeed03dd0762dd4f63efd1d59,a54f1c6d62d2e759a2e6563fdc199bccfebed6b5..3225d3dae4ea4c856ad63534d5f58f9668c1b262
--- 1/lightning/src/ln/peer_handler.rs
--- 2/lightning/src/ln/peer_handler.rs
+++ b/lightning/src/ln/peer_handler.rs
@@@ -367,8 -367,10 +367,10 @@@ struct Peer 
  
        pending_outbound_buffer: LinkedList<Vec<u8>>,
        pending_outbound_buffer_first_msg_offset: usize,
-       // Queue gossip broadcasts separately from `pending_outbound_buffer` so we can easily prioritize
-       // channel messages over them.
+       /// Queue gossip broadcasts separately from `pending_outbound_buffer` so we can easily
+       /// prioritize channel messages over them.
+       ///
+       /// Note that these messages are *not* encrypted/MAC'd, and are only serialized.
        gossip_broadcast_buffer: LinkedList<Vec<u8>>,
        awaiting_write_event: bool,
  
@@@ -822,7 -824,7 +824,7 @@@ impl<Descriptor: SocketDescriptor, CM: 
                        }
                        if peer.should_buffer_gossip_broadcast() {
                                if let Some(msg) = peer.gossip_broadcast_buffer.pop_front() {
-                                       peer.pending_outbound_buffer.push_back(msg);
+                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_buffer(&msg[..]));
                                }
                        }
                        if peer.should_buffer_gossip_backfill() {
@@@ -941,22 -943,19 +943,19 @@@
  
        /// Append a message to a peer's pending outbound/write buffer
        fn enqueue_message<M: wire::Type>(&self, peer: &mut Peer, message: &M) {
-               let mut buffer = VecWriter(Vec::with_capacity(2048));
-               wire::write(message, &mut buffer).unwrap(); // crash if the write failed
- 
                if is_gossip_msg(message.type_id()) {
                        log_gossip!(self.logger, "Enqueueing message {:?} to {}", message, log_pubkey!(peer.their_node_id.unwrap()));
                } else {
                        log_trace!(self.logger, "Enqueueing message {:?} to {}", message, log_pubkey!(peer.their_node_id.unwrap()))
                }
                peer.msgs_sent_since_pong += 1;
-               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&buffer.0[..]));
+               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(message));
        }
  
        /// Append a message to a peer's pending outbound/write gossip broadcast buffer
-       fn enqueue_encoded_gossip_broadcast(&self, peer: &mut Peer, encoded_message: &Vec<u8>) {
+       fn enqueue_encoded_gossip_broadcast(&self, peer: &mut Peer, encoded_message: Vec<u8>) {
                peer.msgs_sent_since_pong += 1;
-               peer.gossip_broadcast_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_message[..]));
+               peer.gossip_broadcast_buffer.push_back(encoded_message);
        }
  
        fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
@@@ -1127,10 -1126,7 +1126,10 @@@
                                                                                                }
                                                                                                (_, Some(ty)) if is_gossip_msg(ty) => {
                                                                                                        log_gossip!(self.logger, "Got an invalid value while deserializing a gossip message");
 -                                                                                                      self.enqueue_message(peer, &msgs::WarningMessage { channel_id: [0; 32], data: "Unreadable/bogus gossip message".to_owned() });
 +                                                                                                      self.enqueue_message(peer, &msgs::WarningMessage {
 +                                                                                                              channel_id: [0; 32],
 +                                                                                                              data: format!("Unreadable/bogus gossip message of type {}", ty),
 +                                                                                                      });
                                                                                                        continue;
                                                                                                }
                                                                                                (msgs::DecodeError::UnknownRequiredFeature, ty) => {
@@@ -1438,7 -1434,7 +1437,7 @@@
                                        if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
                                                continue;
                                        }
-                                       self.enqueue_encoded_gossip_broadcast(&mut *peer, &encoded_msg);
+                                       self.enqueue_encoded_gossip_broadcast(&mut *peer, encoded_msg.clone());
                                }
                        },
                        wire::Message::NodeAnnouncement(ref msg) => {
@@@ -1461,7 -1457,7 +1460,7 @@@
                                        if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
                                                continue;
                                        }
-                                       self.enqueue_encoded_gossip_broadcast(&mut *peer, &encoded_msg);
+                                       self.enqueue_encoded_gossip_broadcast(&mut *peer, encoded_msg.clone());
                                }
                        },
                        wire::Message::ChannelUpdate(ref msg) => {
@@@ -1481,7 -1477,7 +1480,7 @@@
                                        if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
                                                continue;
                                        }
-                                       self.enqueue_encoded_gossip_broadcast(&mut *peer, &encoded_msg);
+                                       self.enqueue_encoded_gossip_broadcast(&mut *peer, encoded_msg.clone());
                                }
                        },
                        _ => debug_assert!(false, "We shouldn't attempt to forward anything but gossip messages"),