Send warning instead of error when we incounter bogus gossip

Author: TheBlueMatt

lightning/src/ln/peer_handler.rs

@@ -902,22 +902,27 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref, CMH: Deref> P
 											Ok(x) => x,
 											Err(e) => {
 												match e {
-													msgs::DecodeError::UnknownVersion => return Err(PeerHandleError { no_connection_possible: false }),
-													msgs::DecodeError::UnknownRequiredFeature => {
+													(_, 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() });
+														continue;
+													}
+													(msgs::DecodeError::UnknownVersion, _) => return Err(PeerHandleError { no_connection_possible: false }),
+													(msgs::DecodeError::UnknownRequiredFeature, _) => {
 														log_gossip!(self.logger, "Got a channel/node announcement with an unknown required feature flag, you may want to update!");
 														continue;
 													}
-													msgs::DecodeError::InvalidValue => {
+													(msgs::DecodeError::InvalidValue, _) => {
 														log_debug!(self.logger, "Got an invalid value while deserializing message");
 														return Err(PeerHandleError { no_connection_possible: false });
 													}
-													msgs::DecodeError::ShortRead => {
+													(msgs::DecodeError::ShortRead, _) => {
 														log_debug!(self.logger, "Deserialization failed due to shortness of message");
 														return Err(PeerHandleError { no_connection_possible: false });
 													}
-													msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError { no_connection_possible: false }),
-													msgs::DecodeError::Io(_) => return Err(PeerHandleError { no_connection_possible: false }),
-													msgs::DecodeError::UnsupportedCompression => {
+													(msgs::DecodeError::BadLengthDescriptor, _) => return Err(PeerHandleError { no_connection_possible: false }),
+													(msgs::DecodeError::Io(_), _) => return Err(PeerHandleError { no_connection_possible: false }),
+													(msgs::DecodeError::UnsupportedCompression, _) => {
 														log_gossip!(self.logger, "We don't support zlib-compressed message fields, sending a warning and ignoring message");
 														self.enqueue_message(peer, &msgs::WarningMessage { channel_id: [0; 32], data: "Unsupported message compression: zlib".to_owned() });
 														continue;

lightning/src/ln/wire.rs

@@ -119,15 +119,20 @@ impl<T> Message<T> where T: core::fmt::Debug + Type {
 /// # Errors
 ///
 /// Returns an error if the message payload code not be decoded as the specified type.
-pub(crate) fn read<R: io::Read, T, H: core::ops::Deref>(
-	buffer: &mut R,
-	custom_reader: H,
-) -> Result<Message<T>, msgs::DecodeError>
-where
+pub(crate) fn read<R: io::Read, T, H: core::ops::Deref>(buffer: &mut R, custom_reader: H)
+-> Result<Message<T>, (msgs::DecodeError, Option<u16>)> where
+	T: core::fmt::Debug + Type + Writeable,
+	H::Target: CustomMessageReader<CustomMessage = T>,
+{
+	let message_type = <u16 as Readable>::read(buffer).map_err(|e| (e, None))?;
+	do_read(buffer, message_type, custom_reader).map_err(|e| (e, Some(message_type)))
+}
+
+fn do_read<R: io::Read, T, H: core::ops::Deref>(buffer: &mut R, message_type: u16, custom_reader: H)
+-> Result<Message<T>, msgs::DecodeError> where
 	T: core::fmt::Debug + Type + Writeable,
 	H::Target: CustomMessageReader<CustomMessage = T>,
 {
-	let message_type = <u16 as Readable>::read(buffer)?;
 	match message_type {
 		msgs::Init::TYPE => {
 			Ok(Message::Init(Readable::read(buffer)?))