Implement DisconnectPeer event + test

fuzz/fuzz_targets/full_stack_target.rs

@@ -107,12 +107,16 @@ impl BroadcasterInterface for TestBroadcaster {
 #[derive(Clone, PartialEq, Eq, Hash)]
 struct Peer {
 	id: u8,
+	connected: bool,
 }
 impl SocketDescriptor for Peer {
 	fn send_data(&mut self, data: &Vec<u8>, write_offset: usize, _resume_read: bool) -> usize {
 		assert!(write_offset < data.len());
 		data.len() - write_offset
 	}
+	fn disconnect_socket(&mut self) {
+		self.connected = false;
+	}
 }
 
 #[inline]

fuzz/fuzz_targets/msg_targets/gen_target.sh

@@ -1,4 +1,4 @@
-for target in CommitmentSigned FundingCreated FundingLocked FundingSigned OpenChannel RevokeAndACK Shutdown UpdateAddHTLC UpdateFailHTLC UpdateFailMalformedHTLC UpdateFee UpdateFulfillHTLC AcceptChannel ClosingSigned; do
+for target in CommitmentSigned FundingCreated FundingLocked FundingSigned OpenChannel RevokeAndACK Shutdown UpdateAddHTLC UpdateFailHTLC UpdateFailMalformedHTLC UpdateFee UpdateFulfillHTLC AcceptChannel ClosingSigned ErrorMessage; do
 	tn=$(echo $target | sed 's/\([a-z0-9]\)\([A-Z]\)/\1_\L\2/g')
 	fn=msg_$(echo $tn | tr '[:upper:]' '[:lower:]')_target.rs
 	cat msg_target_template.txt | sed s/MSG_TARGET/$target/ > $fn

fuzz/fuzz_targets/msg_targets/msg_error_message_target.rs

@@ -0,0 +1,48 @@
+// This file is auto-generated by gen_target.sh based on msg_target_template.txt
+// To modify it, modify msg_target_template.txt and run gen_target.sh instead.
+
+extern crate lightning;
+
+use lightning::ln::msgs;
+use lightning::util::reset_rng_state;
+
+use lightning::ln::msgs::{MsgEncodable, MsgDecodable};
+
+mod utils;
+
+#[inline]
+pub fn do_test(data: &[u8]) {
+	reset_rng_state();
+	test_msg!(msgs::ErrorMessage, data);
+}
+
+#[cfg(feature = "afl")]
+extern crate afl;
+#[cfg(feature = "afl")]
+fn main() {
+	afl::read_stdio_bytes(|data| {
+		do_test(&data);
+	});
+}
+
+#[cfg(feature = "honggfuzz")]
+#[macro_use] extern crate honggfuzz;
+#[cfg(feature = "honggfuzz")]
+fn main() {
+	loop {
+		fuzz!(|data| {
+			do_test(data);
+		});
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use utils::extend_vec_from_hex;
+	#[test]
+	fn duplicate_crash() {
+		let mut a = Vec::new();
+		extend_vec_from_hex("00", &mut a);
+		super::do_test(&a);
+	}
+}

src/ln/channel.rs

@@ -328,7 +328,7 @@ macro_rules! secp_call {
 		match $res {
 			Ok(key) => key,
 			//TODO: make the error a parameter
-			Err(_) => return Err(HandleError{err: $err, action: Some(msgs::ErrorAction::DisconnectPeer{})})
+			Err(_) => return Err(HandleError{err: $err, action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })})
 		}
 	};
 }
@@ -433,10 +433,10 @@ impl Channel {
 
 	fn check_remote_fee(fee_estimator: &FeeEstimator, feerate_per_kw: u32) -> Result<(), HandleError> {
 		if (feerate_per_kw as u64) < fee_estimator.get_est_sat_per_vbyte(ConfirmationTarget::Background) * 250 {
-			return Err(HandleError{err: "Peer's feerate much too low", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Peer's feerate much too low", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if (feerate_per_kw as u64) > fee_estimator.get_est_sat_per_vbyte(ConfirmationTarget::HighPriority) * 375 { // 375 = 250 * 1.5x
-			return Err(HandleError{err: "Peer's feerate much too high", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Peer's feerate much too high", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		Ok(())
 	}
@@ -448,29 +448,32 @@ impl Channel {
 	pub fn new_from_req(fee_estimator: &FeeEstimator, chan_keys: ChannelKeys, their_node_id: PublicKey, msg: &msgs::OpenChannel, user_id: u64, announce_publicly: bool) -> Result<Channel, HandleError> {
 		// Check sanity of message fields:
 		if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
-			return Err(HandleError{err: "funding value > 2^24", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "funding value > 2^24", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if msg.channel_reserve_satoshis > msg.funding_satoshis {
-			return Err(HandleError{err: "Bogus channel_reserve_satoshis", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Bogus channel_reserve_satoshis", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if msg.push_msat > (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 {
-			return Err(HandleError{err: "push_msat more than highest possible value", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "push_msat more than highest possible value", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if msg.dust_limit_satoshis > msg.funding_satoshis {
-			return Err(HandleError{err: "Peer never wants payout outputs?", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Peer never wants payout outputs?", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
+		}
+		if msg.max_htlc_value_in_flight_msat > msg.funding_satoshis * 1000 {
+			return Err(HandleError{err: "Bogus max_htlc_value_in_flight_satoshis", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if msg.htlc_minimum_msat >= (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000 {
-			return Err(HandleError{err: "Minimum htlc value is full channel value", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Minimum htlc value is full channel value", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		Channel::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
 		if msg.to_self_delay > MAX_LOCAL_BREAKDOWN_TIMEOUT {
-			return Err(HandleError{err: "They wanted our payments to be delayed by a needlessly long period", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "They wanted our payments to be delayed by a needlessly long period", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if msg.max_accepted_htlcs < 1 {
-			return Err(HandleError{err: "0 max_accpted_htlcs makes for a useless channel", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "0 max_accpted_htlcs makes for a useless channel", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		if (msg.channel_flags & 254) != 0 {
-			return Err(HandleError{err: "unknown channel_flags", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "unknown channel_flags", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 
 		// Convert things into internal flags and prep our state:

src/ln/channelmanager.rs

@@ -676,6 +676,16 @@ impl ChannelManager {
 	/// Call this upon creation of a funding transaction for the given channel.
 	/// Panics if a funding transaction has already been provided for this channel.
 	pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], funding_txo: OutPoint) {
+
+		macro_rules! add_pending_event {
+			($event: expr) => {
+				{
+					let mut pending_events = self.pending_events.lock().unwrap();
+					pending_events.push($event);
+				}
+			}
+		}
+
 		let (chan, msg, chan_monitor) = {
 			let mut channel_state = self.channel_state.lock().unwrap();
 			match channel_state.by_id.remove(temporary_channel_id) {
@@ -684,10 +694,15 @@ impl ChannelManager {
 						Ok(funding_msg) => {
 							(chan, funding_msg.0, funding_msg.1)
 						},
-						Err(_e) => {
-							//TODO: Push e to pendingevents
+						Err(e) => {
+							mem::drop(channel_state);
+							add_pending_event!(events::Event::DisconnectPeer {
+								node_id: chan.get_their_node_id(),
+								msg: if let Some(msgs::ErrorAction::DisconnectPeer { msg } ) = e.action { msg } else { None },
+							});
+
 							return;
-						}
+						},
 					}
 				},
 				None => return
@@ -696,13 +711,10 @@ impl ChannelManager {
 		if let Err(_e) = self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
 			unimplemented!(); // maybe remove from claimable_htlcs?
 		}
-		{
-			let mut pending_events = self.pending_events.lock().unwrap();
-			pending_events.push(events::Event::SendFundingCreated {
-				node_id: chan.get_their_node_id(),
-				msg: msg,
-			});
-		}
+		add_pending_event!(events::Event::SendFundingCreated {
+			node_id: chan.get_their_node_id(),
+			msg: msg,
+		});
 
 		let mut channel_state = self.channel_state.lock().unwrap();
 		channel_state.by_id.insert(chan.channel_id(), chan);

src/ln/msgs.rs

@@ -138,6 +138,11 @@ pub struct Init {
 	pub local_features: LocalFeatures,
 }
 
+pub struct ErrorMessage {
+	pub channel_id: [u8; 32],
+	pub data: String,
+}
+
 pub struct Ping {
 	pub ponglen: u16,
 	pub byteslen: u16,
@@ -372,9 +377,15 @@ pub enum ErrorAction {
 		msg: UpdateFailHTLC
 	},
 	/// The peer took some action which made us think they were useless. Disconnect them.
-	DisconnectPeer,
+	DisconnectPeer {
+		msg: Option<ErrorMessage>
+	},
 	/// The peer did something harmless that we weren't able to process, just log and ignore
 	IgnoreError,
+	/// The peer did something incorrect. Tell them.
+	SendErrorMessage {
+		msg: ErrorMessage
+	},
 }
 
 pub struct HandleError { //TODO: rename me
@@ -1562,3 +1573,35 @@ impl MsgEncodable for OnionErrorPacket {
 		res
 	}
 }
+
+impl MsgEncodable for ErrorMessage {
+	fn encode(&self) -> Vec<u8> {
+		let mut res = Vec::with_capacity(34 + self.data.len());
+		res.extend_from_slice(&self.channel_id);
+		res.extend_from_slice(&byte_utils::be16_to_array(self.data.len() as u16));
+		res.extend_from_slice(&self.data.as_bytes());
+		res
+	}
+}
+
+impl MsgDecodable for ErrorMessage {
+	fn decode(v: &[u8]) -> Result<Self,DecodeError> {
+		if v.len() < 34 {
+			return Err(DecodeError::WrongLength);
+		}
+		let len = byte_utils::slice_to_be16(&v[33..34]);
+		let mut data = String::new();
+		if len > 0 {
+			data = String::from_utf8(v[35..len as usize].to_vec()).unwrap();
+			if len != data.len() as u16 {
+				return Err(DecodeError::WrongLength);
+			}
+		}
+		let mut channel_id = [0; 32];
+		channel_id[..].copy_from_slice(&v[0..32]);
+		Ok(Self {
+			channel_id,
+			data: data,
+		})
+	}
+}

src/ln/peer_channel_encryptor.rs

@@ -147,7 +147,7 @@ impl PeerChannelEncryptor {
 
 		let mut chacha = ChaCha20Poly1305RFC::new(key, &nonce, h);
 		if !chacha.decrypt(&cyphertext[0..cyphertext.len() - 16], res, &cyphertext[cyphertext.len() - 16..]) {
-			return Err(HandleError{err: "Bad MAC", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Bad MAC", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 		Ok(())
 	}
@@ -195,11 +195,11 @@ impl PeerChannelEncryptor {
 		assert_eq!(act.len(), 50);
 
 		if act[0] != 0 {
-			return Err(HandleError{err: "Unknown handshake version number", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+			return Err(HandleError{err: "Unknown handshake version number", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 		}
 
 		let their_pub = match PublicKey::from_slice(secp_ctx, &act[1..34]) {
-			Err(_) => return Err(HandleError{err: "Invalid public key", action: Some(msgs::ErrorAction::DisconnectPeer{})}),
+			Err(_) => return Err(HandleError{err: "Invalid public key", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}),
 			Ok(key) => key,
 		};
 
@@ -349,14 +349,14 @@ impl PeerChannelEncryptor {
 							panic!("Requested act at wrong step");
 						}
 						if act_three[0] != 0 {
-							return Err(HandleError{err: "Unknown handshake version number", action: Some(msgs::ErrorAction::DisconnectPeer{})});
+							return Err(HandleError{err: "Unknown handshake version number", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })});
 						}
 
 						let mut their_node_id = [0; 33];
 						PeerChannelEncryptor::decrypt_with_ad(&mut their_node_id, 1, &temp_k2.unwrap(), &bidirectional_state.h, &act_three[1..50])?;
 						self.their_node_id = Some(match PublicKey::from_slice(&self.secp_ctx, &their_node_id) {
 							Ok(key) => key,
-							Err(_) => return Err(HandleError{err: "Bad node_id from peer", action: Some(msgs::ErrorAction::DisconnectPeer{})}),
+							Err(_) => return Err(HandleError{err: "Bad node_id from peer", action: Some(msgs::ErrorAction::DisconnectPeer{ msg: None })}),
 						});
 
 						let mut sha = Sha256::new();