Add MPP ID to pending_outbound_htlcs

We'll use this to correlate MPP shards in upcoming commits

Author: valentinewallace

lightning/src/ln/channelmanager.rs

@@ -491,8 +491,11 @@ pub struct ChannelManager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref,
 	/// which may generate a claim event, we may receive similar duplicate claim/fail MonitorEvents
 	/// after reloading from disk while replaying blocks against ChannelMonitors.
 	///
+	/// Each payment has each of its MPP fragment's session_priv bytes in the HashSet of the map
+	/// (even payments over a single path).
+	///
 	/// Locked *after* channel_state.
-	pending_outbound_payments: Mutex<HashSet<[u8; 32]>>,
+	pending_outbound_payments: Mutex<HashMap<MppId, HashSet<[u8; 32]>>>,
 
 	our_network_key: SecretKey,
 	our_network_pubkey: PublicKey,
@@ -1156,7 +1159,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 				pending_msg_events: Vec::new(),
 			}),
 			pending_inbound_payments: Mutex::new(HashMap::new()),
-			pending_outbound_payments: Mutex::new(HashSet::new()),
+			pending_outbound_payments: Mutex::new(HashMap::new()),
 
 			our_network_key: keys_manager.get_node_secret(),
 			our_network_pubkey: PublicKey::from_secret_key(&secp_ctx, &keys_manager.get_node_secret()),
@@ -1853,7 +1856,9 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 		let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
 
 		let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-		assert!(self.pending_outbound_payments.lock().unwrap().insert(session_priv_bytes));
+		let mut pending_outbounds = self.pending_outbound_payments.lock().unwrap();
+		let sessions = pending_outbounds.entry(mpp_id).or_insert(HashSet::new());
+		assert!(sessions.insert(session_priv_bytes));
 
 		let err: Result<(), _> = loop {
 			let mut channel_lock = self.channel_state.lock().unwrap();
@@ -2832,25 +2837,29 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 					self.fail_htlc_backwards_internal(channel_state,
 						htlc_src, &payment_hash, HTLCFailReason::Reason { failure_code, data: onion_failure_data});
 				},
-				HTLCSource::OutboundRoute { session_priv, .. } => {
-					if {
-						let mut session_priv_bytes = [0; 32];
-						session_priv_bytes.copy_from_slice(&session_priv[..]);
-						self.pending_outbound_payments.lock().unwrap().remove(&session_priv_bytes)
-					} {
-						self.pending_events.lock().unwrap().push(
-							events::Event::PaymentFailed {
-								payment_hash,
-								rejected_by_dest: false,
-#[cfg(test)]
-								error_code: None,
-#[cfg(test)]
-								error_data: None,
+				HTLCSource::OutboundRoute { session_priv, mpp_id, .. } => {
+					let mut session_priv_bytes = [0; 32];
+					session_priv_bytes.copy_from_slice(&session_priv[..]);
+					let mut outbounds = self.pending_outbound_payments.lock().unwrap();
+					if let Some(sessions) = outbounds.get_mut(&mpp_id) {
+						if sessions.remove(&session_priv_bytes) {
+							self.pending_events.lock().unwrap().push(
+								events::Event::PaymentFailed {
+									payment_hash,
+									rejected_by_dest: false,
+									#[cfg(test)]
+									error_code: None,
+									#[cfg(test)]
+									error_data: None,
+								}
+							);
+							if sessions.len() == 0 {
+								outbounds.remove(&mpp_id);
 							}
-						)
-					} else {
-						log_trace!(self.logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
+							continue
+						}
 					}
+					log_trace!(self.logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
 				},
 			};
 		}
@@ -2872,14 +2881,21 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 		// from block_connected which may run during initialization prior to the chain_monitor
 		// being fully configured. See the docs for `ChannelManagerReadArgs` for more.
 		match source {
-			HTLCSource::OutboundRoute { ref path, session_priv, .. } => {
-				if {
-					let mut session_priv_bytes = [0; 32];
-					session_priv_bytes.copy_from_slice(&session_priv[..]);
-					!self.pending_outbound_payments.lock().unwrap().remove(&session_priv_bytes)
-				} {
+			HTLCSource::OutboundRoute { ref path, session_priv, mpp_id, .. } => {
+				let mut session_priv_bytes = [0; 32];
+				session_priv_bytes.copy_from_slice(&session_priv[..]);
+				let mut outbounds = self.pending_outbound_payments.lock().unwrap();
+				if let Some(sessions) = outbounds.get_mut(&mpp_id) {
+					if !sessions.remove(&session_priv_bytes) {
+						log_trace!(self.logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
+						return;
+					}
+					if sessions.len() == 0 {
+						outbounds.remove(&mpp_id);
+					}
+				} else {
 					log_trace!(self.logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
-					return;
+					return
 				}
 				log_trace!(self.logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
 				mem::drop(channel_state_lock);
@@ -3123,20 +3139,23 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
 	fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<Signer>>, source: HTLCSource, payment_preimage: PaymentPreimage, forwarded_htlc_value_msat: Option<u64>, from_onchain: bool) {
 		match source {
-			HTLCSource::OutboundRoute { session_priv, .. } => {
+			HTLCSource::OutboundRoute { session_priv, mpp_id, .. } => {
 				mem::drop(channel_state_lock);
-				if {
-					let mut session_priv_bytes = [0; 32];
-					session_priv_bytes.copy_from_slice(&session_priv[..]);
-					self.pending_outbound_payments.lock().unwrap().remove(&session_priv_bytes)
-				} {
-					let mut pending_events = self.pending_events.lock().unwrap();
-					pending_events.push(events::Event::PaymentSent {
-						payment_preimage
-					});
-				} else {
-					log_trace!(self.logger, "Received duplicative fulfill for HTLC with payment_preimage {}", log_bytes!(payment_preimage.0));
+				let mut session_priv_bytes = [0; 32];
+				session_priv_bytes.copy_from_slice(&session_priv[..]);
+				let mut outbounds = self.pending_outbound_payments.lock().unwrap();
+				if let Some(sessions) = outbounds.get_mut(&mpp_id) {
+					if sessions.remove(&session_priv_bytes) {
+						self.pending_events.lock().unwrap().push(
+							events::Event::PaymentSent { payment_preimage }
+						);
+						if sessions.len() == 0 {
+							outbounds.remove(&mpp_id);
+						}
+						return
+					}
 				}
+				log_trace!(self.logger, "Received duplicative fulfill for HTLC with payment_preimage {}", log_bytes!(payment_preimage.0));
 			},
 			HTLCSource::PreviousHopData(hop_data) => {
 				let prev_outpoint = hop_data.outpoint;
@@ -5110,10 +5129,15 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable f
 			pending_payment.write(writer)?;
 		}
 
+		(0 as u64).write(writer)?; // for backwards compat with the old format of pending_outbound_payments
 		let pending_outbound_payments = self.pending_outbound_payments.lock().unwrap();
 		(pending_outbound_payments.len() as u64).write(writer)?;
-		for session_priv in pending_outbound_payments.iter() {
-			session_priv.write(writer)?;
+		for (mpp_id, session_priv_set) in pending_outbound_payments.iter() {
+			mpp_id.write(writer)?;
+			(session_priv_set.len() as u64).write(writer)?;
+			for session_priv in session_priv_set.iter() {
+				session_priv.write(writer)?;
+			}
 		}
 
 		write_tlv_fields!(writer, {});
@@ -5369,11 +5393,33 @@ impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
 			}
 		}
 
-		let pending_outbound_payments_count: u64 = Readable::read(reader)?;
-		let mut pending_outbound_payments: HashSet<[u8; 32]> = HashSet::with_capacity(cmp::min(pending_outbound_payments_count as usize, MAX_ALLOC_SIZE/32));
-		for _ in 0..pending_outbound_payments_count {
-			if !pending_outbound_payments.insert(Readable::read(reader)?) {
-				return Err(DecodeError::InvalidValue);
+		let pending_outbound_payments_count_compat: u64 = Readable::read(reader)?;
+		let mut pending_outbound_payments: HashMap<MppId, HashSet<[u8; 32]>> =
+			HashMap::with_capacity(cmp::min(pending_outbound_payments_count_compat as usize, MAX_ALLOC_SIZE/32));
+
+		match pending_outbound_payments_count_compat {
+			0 => {
+				// TODO: is this line OK for old clients?
+				let pending_outbound_payments_count: u64 = Readable::read(reader)?;
+				for _ in 0..pending_outbound_payments_count {
+					let mpp_id = Readable::read(reader)?;
+					let mut sessions = HashSet::new();
+					let session_count: u64 = Readable::read(reader)?;
+					for _ in 0..session_count {
+						if !sessions.insert(Readable::read(reader)?) {
+							return Err(DecodeError::InvalidValue);
+						}
+					}
+					pending_outbound_payments.insert(mpp_id, sessions);
+				}
+			},
+			n => {
+				for _ in 0..n {
+					let session_priv = Readable::read(reader)?;
+					if pending_outbound_payments.insert(MppId(session_priv), [session_priv].iter().cloned().collect()).is_some() {
+						return Err(DecodeError::InvalidValue);
+					};
+				}
 			}
 		}