Replace OnionHopData with OutboundPayload for outbound onions
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 7df125b9323b9c3987cbfa91cf7dbaf1114d3a7d..6bfa4f0b03a7c225a84b556d15a6cc6343b8d180 100644 (file)
@@ -341,7 +341,7 @@ impl HTLCSource {
        }
 }
 
-struct ReceiveError {
+struct InboundOnionErr {
        err_code: u16,
        err_data: Vec<u8>,
        msg: &'static str,
@@ -530,6 +530,13 @@ enum BackgroundEvent {
                funding_txo: OutPoint,
                update: ChannelMonitorUpdate
        },
+       /// Some [`ChannelMonitorUpdate`] (s) completed before we were serialized but we still have
+       /// them marked pending, thus we need to run any [`MonitorUpdateCompletionAction`] (s) pending
+       /// on a channel.
+       MonitorUpdatesComplete {
+               counterparty_node_id: PublicKey,
+               channel_id: [u8; 32],
+       },
 }
 
 #[derive(Debug)]
@@ -2609,14 +2616,64 @@ where
                }
        }
 
+       fn construct_fwd_pending_htlc_info(
+               &self, msg: &msgs::UpdateAddHTLC, hop_data: msgs::InboundOnionPayload, hop_hmac: [u8; 32],
+               new_packet_bytes: [u8; onion_utils::ONION_DATA_LEN], shared_secret: [u8; 32],
+               next_packet_pubkey_opt: Option<Result<PublicKey, secp256k1::Error>>
+       ) -> Result<PendingHTLCInfo, InboundOnionErr> {
+               debug_assert!(next_packet_pubkey_opt.is_some());
+               let outgoing_packet = msgs::OnionPacket {
+                       version: 0,
+                       public_key: next_packet_pubkey_opt.unwrap_or(Err(secp256k1::Error::InvalidPublicKey)),
+                       hop_data: new_packet_bytes,
+                       hmac: hop_hmac,
+               };
+
+               let (short_channel_id, amt_to_forward, outgoing_cltv_value) = match hop_data {
+                       msgs::InboundOnionPayload::Forward { short_channel_id, amt_to_forward, outgoing_cltv_value } =>
+                               (short_channel_id, amt_to_forward, outgoing_cltv_value),
+                       msgs::InboundOnionPayload::Receive { .. } =>
+                               return Err(InboundOnionErr {
+                                       msg: "Final Node OnionHopData provided for us as an intermediary node",
+                                       err_code: 0x4000 | 22,
+                                       err_data: Vec::new(),
+                               }),
+               };
+
+               Ok(PendingHTLCInfo {
+                       routing: PendingHTLCRouting::Forward {
+                               onion_packet: outgoing_packet,
+                               short_channel_id,
+                       },
+                       payment_hash: msg.payment_hash,
+                       incoming_shared_secret: shared_secret,
+                       incoming_amt_msat: Some(msg.amount_msat),
+                       outgoing_amt_msat: amt_to_forward,
+                       outgoing_cltv_value,
+                       skimmed_fee_msat: None,
+               })
+       }
+
        fn construct_recv_pending_htlc_info(
-               &self, hop_data: msgs::OnionHopData, shared_secret: [u8; 32], payment_hash: PaymentHash,
+               &self, hop_data: msgs::InboundOnionPayload, shared_secret: [u8; 32], payment_hash: PaymentHash,
                amt_msat: u64, cltv_expiry: u32, phantom_shared_secret: Option<[u8; 32]>, allow_underpay: bool,
                counterparty_skimmed_fee_msat: Option<u64>,
-       ) -> Result<PendingHTLCInfo, ReceiveError> {
+       ) -> Result<PendingHTLCInfo, InboundOnionErr> {
+               let (payment_data, keysend_preimage, onion_amt_msat, outgoing_cltv_value, payment_metadata) = match hop_data {
+                       msgs::InboundOnionPayload::Receive {
+                               payment_data, keysend_preimage, amt_msat, outgoing_cltv_value, payment_metadata, ..
+                       } =>
+                               (payment_data, keysend_preimage, amt_msat, outgoing_cltv_value, payment_metadata),
+                       _ =>
+                               return Err(InboundOnionErr {
+                                       err_code: 0x4000|22,
+                                       err_data: Vec::new(),
+                                       msg: "Got non final data with an HMAC of 0",
+                               }),
+               };
                // final_incorrect_cltv_expiry
-               if hop_data.outgoing_cltv_value > cltv_expiry {
-                       return Err(ReceiveError {
+               if outgoing_cltv_value > cltv_expiry {
+                       return Err(InboundOnionErr {
                                msg: "Upstream node set CLTV to less than the CLTV set by the sender",
                                err_code: 18,
                                err_data: cltv_expiry.to_be_bytes().to_vec()
@@ -2630,85 +2687,74 @@ where
                // payment logic has enough time to fail the HTLC backward before our onchain logic triggers a
                // channel closure (see HTLC_FAIL_BACK_BUFFER rationale).
                let current_height: u32 = self.best_block.read().unwrap().height();
-               if (hop_data.outgoing_cltv_value as u64) <= current_height as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
+               if (outgoing_cltv_value as u64) <= current_height as u64 + HTLC_FAIL_BACK_BUFFER as u64 + 1 {
                        let mut err_data = Vec::with_capacity(12);
                        err_data.extend_from_slice(&amt_msat.to_be_bytes());
                        err_data.extend_from_slice(&current_height.to_be_bytes());
-                       return Err(ReceiveError {
+                       return Err(InboundOnionErr {
                                err_code: 0x4000 | 15, err_data,
                                msg: "The final CLTV expiry is too soon to handle",
                        });
                }
-               if (!allow_underpay && hop_data.amt_to_forward > amt_msat) ||
-                       (allow_underpay && hop_data.amt_to_forward >
+               if (!allow_underpay && onion_amt_msat > amt_msat) ||
+                       (allow_underpay && onion_amt_msat >
                         amt_msat.saturating_add(counterparty_skimmed_fee_msat.unwrap_or(0)))
                {
-                       return Err(ReceiveError {
+                       return Err(InboundOnionErr {
                                err_code: 19,
                                err_data: amt_msat.to_be_bytes().to_vec(),
                                msg: "Upstream node sent less than we were supposed to receive in payment",
                        });
                }
 
-               let routing = match hop_data.format {
-                       msgs::OnionHopDataFormat::NonFinalNode { .. } => {
-                               return Err(ReceiveError {
+               let routing = if let Some(payment_preimage) = keysend_preimage {
+                       // We need to check that the sender knows the keysend preimage before processing this
+                       // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
+                       // could discover the final destination of X, by probing the adjacent nodes on the route
+                       // with a keysend payment of identical payment hash to X and observing the processing
+                       // time discrepancies due to a hash collision with X.
+                       let hashed_preimage = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
+                       if hashed_preimage != payment_hash {
+                               return Err(InboundOnionErr {
                                        err_code: 0x4000|22,
                                        err_data: Vec::new(),
-                                       msg: "Got non final data with an HMAC of 0",
+                                       msg: "Payment preimage didn't match payment hash",
                                });
-                       },
-                       msgs::OnionHopDataFormat::FinalNode { payment_data, keysend_preimage, payment_metadata } => {
-                               if let Some(payment_preimage) = keysend_preimage {
-                                       // We need to check that the sender knows the keysend preimage before processing this
-                                       // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
-                                       // could discover the final destination of X, by probing the adjacent nodes on the route
-                                       // with a keysend payment of identical payment hash to X and observing the processing
-                                       // time discrepancies due to a hash collision with X.
-                                       let hashed_preimage = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
-                                       if hashed_preimage != payment_hash {
-                                               return Err(ReceiveError {
-                                                       err_code: 0x4000|22,
-                                                       err_data: Vec::new(),
-                                                       msg: "Payment preimage didn't match payment hash",
-                                               });
-                                       }
-                                       if !self.default_configuration.accept_mpp_keysend && payment_data.is_some() {
-                                               return Err(ReceiveError {
-                                                       err_code: 0x4000|22,
-                                                       err_data: Vec::new(),
-                                                       msg: "We don't support MPP keysend payments",
-                                               });
-                                       }
-                                       PendingHTLCRouting::ReceiveKeysend {
-                                               payment_data,
-                                               payment_preimage,
-                                               payment_metadata,
-                                               incoming_cltv_expiry: hop_data.outgoing_cltv_value,
-                                       }
-                               } else if let Some(data) = payment_data {
-                                       PendingHTLCRouting::Receive {
-                                               payment_data: data,
-                                               payment_metadata,
-                                               incoming_cltv_expiry: hop_data.outgoing_cltv_value,
-                                               phantom_shared_secret,
-                                       }
-                               } else {
-                                       return Err(ReceiveError {
-                                               err_code: 0x4000|0x2000|3,
-                                               err_data: Vec::new(),
-                                               msg: "We require payment_secrets",
-                                       });
-                               }
-                       },
+                       }
+                       if !self.default_configuration.accept_mpp_keysend && payment_data.is_some() {
+                               return Err(InboundOnionErr {
+                                       err_code: 0x4000|22,
+                                       err_data: Vec::new(),
+                                       msg: "We don't support MPP keysend payments",
+                               });
+                       }
+                       PendingHTLCRouting::ReceiveKeysend {
+                               payment_data,
+                               payment_preimage,
+                               payment_metadata,
+                               incoming_cltv_expiry: outgoing_cltv_value,
+                       }
+               } else if let Some(data) = payment_data {
+                       PendingHTLCRouting::Receive {
+                               payment_data: data,
+                               payment_metadata,
+                               incoming_cltv_expiry: outgoing_cltv_value,
+                               phantom_shared_secret,
+                       }
+               } else {
+                       return Err(InboundOnionErr {
+                               err_code: 0x4000|0x2000|3,
+                               err_data: Vec::new(),
+                               msg: "We require payment_secrets",
+                       });
                };
                Ok(PendingHTLCInfo {
                        routing,
                        payment_hash,
                        incoming_shared_secret: shared_secret,
                        incoming_amt_msat: Some(amt_msat),
-                       outgoing_amt_msat: hop_data.amt_to_forward,
-                       outgoing_cltv_value: hop_data.outgoing_cltv_value,
+                       outgoing_amt_msat: onion_amt_msat,
+                       outgoing_cltv_value,
                        skimmed_fee_msat: counterparty_skimmed_fee_msat,
                })
        }
@@ -2772,9 +2818,8 @@ where
                };
                let (outgoing_scid, outgoing_amt_msat, outgoing_cltv_value, next_packet_pk_opt) = match next_hop {
                        onion_utils::Hop::Forward {
-                               next_hop_data: msgs::OnionHopData {
-                                       format: msgs::OnionHopDataFormat::NonFinalNode { short_channel_id }, amt_to_forward,
-                                       outgoing_cltv_value,
+                               next_hop_data: msgs::InboundOnionPayload::Forward {
+                                       short_channel_id, amt_to_forward, outgoing_cltv_value
                                }, ..
                        } => {
                                let next_pk = onion_utils::next_hop_packet_pubkey(&self.secp_ctx,
@@ -2784,9 +2829,7 @@ where
                        // We'll do receive checks in [`Self::construct_pending_htlc_info`] so we have access to the
                        // inbound channel's state.
                        onion_utils::Hop::Receive { .. } => return Ok((next_hop, shared_secret, None)),
-                       onion_utils::Hop::Forward {
-                               next_hop_data: msgs::OnionHopData { format: msgs::OnionHopDataFormat::FinalNode { .. }, .. }, ..
-                       } => {
+                       onion_utils::Hop::Forward { next_hop_data: msgs::InboundOnionPayload::Receive { .. }, .. } => {
                                return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0; 0]);
                        }
                };
@@ -2957,37 +3000,15 @@ where
                                                // delay) once they've send us a commitment_signed!
                                                PendingHTLCStatus::Forward(info)
                                        },
-                                       Err(ReceiveError { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
+                                       Err(InboundOnionErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
                                }
                        },
                        onion_utils::Hop::Forward { next_hop_data, next_hop_hmac, new_packet_bytes } => {
-                               debug_assert!(next_packet_pubkey_opt.is_some());
-                               let outgoing_packet = msgs::OnionPacket {
-                                       version: 0,
-                                       public_key: next_packet_pubkey_opt.unwrap_or(Err(secp256k1::Error::InvalidPublicKey)),
-                                       hop_data: new_packet_bytes,
-                                       hmac: next_hop_hmac.clone(),
-                               };
-
-                               let short_channel_id = match next_hop_data.format {
-                                       msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
-                                       msgs::OnionHopDataFormat::FinalNode { .. } => {
-                                               return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
-                                       },
-                               };
-
-                               PendingHTLCStatus::Forward(PendingHTLCInfo {
-                                       routing: PendingHTLCRouting::Forward {
-                                               onion_packet: outgoing_packet,
-                                               short_channel_id,
-                                       },
-                                       payment_hash: msg.payment_hash.clone(),
-                                       incoming_shared_secret: shared_secret,
-                                       incoming_amt_msat: Some(msg.amount_msat),
-                                       outgoing_amt_msat: next_hop_data.amt_to_forward,
-                                       outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
-                                       skimmed_fee_msat: None,
-                               })
+                               match self.construct_fwd_pending_htlc_info(msg, next_hop_data, next_hop_hmac,
+                                       new_packet_bytes, shared_secret, next_packet_pubkey_opt) {
+                                       Ok(info) => PendingHTLCStatus::Forward(info),
+                                       Err(InboundOnionErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
+                               }
                        }
                }
        }
@@ -3770,7 +3791,7 @@ where
                                                                                                                        outgoing_cltv_value, Some(phantom_shared_secret), false, None)
                                                                                                                {
                                                                                                                        Ok(info) => phantom_receives.push((prev_short_channel_id, prev_funding_outpoint, prev_user_channel_id, vec![(info, prev_htlc_id)])),
-                                                                                                                       Err(ReceiveError { err_code, err_data, msg }) => failed_payment!(msg, err_code, err_data, Some(phantom_shared_secret))
+                                                                                                                       Err(InboundOnionErr { err_code, err_data, msg }) => failed_payment!(msg, err_code, err_data, Some(phantom_shared_secret))
                                                                                                                }
                                                                                                        },
                                                                                                        _ => panic!(),
@@ -4194,6 +4215,22 @@ where
                                        }
                                        let _ = handle_error!(self, res, counterparty_node_id);
                                },
+                               BackgroundEvent::MonitorUpdatesComplete { counterparty_node_id, channel_id } => {
+                                       let per_peer_state = self.per_peer_state.read().unwrap();
+                                       if let Some(peer_state_mutex) = per_peer_state.get(&counterparty_node_id) {
+                                               let mut peer_state_lock = peer_state_mutex.lock().unwrap();
+                                               let peer_state = &mut *peer_state_lock;
+                                               if let Some(chan) = peer_state.channel_by_id.get_mut(&channel_id) {
+                                                       handle_monitor_update_completion!(self, peer_state_lock, peer_state, per_peer_state, chan);
+                                               } else {
+                                                       let update_actions = peer_state.monitor_update_blocked_actions
+                                                               .remove(&channel_id).unwrap_or(Vec::new());
+                                                       mem::drop(peer_state_lock);
+                                                       mem::drop(per_peer_state);
+                                                       self.handle_monitor_update_completion_actions(update_actions);
+                                               }
+                                       }
+                               },
                        }
                }
                NotifyOption::DoPersist
@@ -5004,24 +5041,29 @@ where
                if peer_state_mutex_opt.is_none() { return }
                peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
                let peer_state = &mut *peer_state_lock;
-               let mut channel = {
-                       match peer_state.channel_by_id.entry(funding_txo.to_channel_id()){
-                               hash_map::Entry::Occupied(chan) => chan,
-                               hash_map::Entry::Vacant(_) => return,
-                       }
-               };
+               let channel =
+                       if let Some(chan) = peer_state.channel_by_id.get_mut(&funding_txo.to_channel_id()) {
+                               chan
+                       } else {
+                               let update_actions = peer_state.monitor_update_blocked_actions
+                                       .remove(&funding_txo.to_channel_id()).unwrap_or(Vec::new());
+                               mem::drop(peer_state_lock);
+                               mem::drop(per_peer_state);
+                               self.handle_monitor_update_completion_actions(update_actions);
+                               return;
+                       };
                let remaining_in_flight =
                        if let Some(pending) = peer_state.in_flight_monitor_updates.get_mut(funding_txo) {
                                pending.retain(|upd| upd.update_id > highest_applied_update_id);
                                pending.len()
                        } else { 0 };
                log_trace!(self.logger, "ChannelMonitor updated to {}. Current highest is {}. {} pending in-flight updates.",
-                       highest_applied_update_id, channel.get().context.get_latest_monitor_update_id(),
+                       highest_applied_update_id, channel.context.get_latest_monitor_update_id(),
                        remaining_in_flight);
-               if !channel.get().is_awaiting_monitor_update() || channel.get().context.get_latest_monitor_update_id() != highest_applied_update_id {
+               if !channel.is_awaiting_monitor_update() || channel.context.get_latest_monitor_update_id() != highest_applied_update_id {
                        return;
                }
-               handle_monitor_update_completion!(self, peer_state_lock, peer_state, per_peer_state, channel.get_mut());
+               handle_monitor_update_completion!(self, peer_state_lock, peer_state, per_peer_state, channel);
        }
 
        /// Accepts a request to open a channel after a [`Event::OpenChannelRequest`].
@@ -8521,6 +8563,16 @@ where
                                                        update: update.clone(),
                                                });
                                }
+                               if $chan_in_flight_upds.is_empty() {
+                                       // We had some updates to apply, but it turns out they had completed before we
+                                       // were serialized, we just weren't notified of that. Thus, we may have to run
+                                       // the completion actions for any monitor updates, but otherwise are done.
+                                       pending_background_events.push(
+                                               BackgroundEvent::MonitorUpdatesComplete {
+                                                       counterparty_node_id: $counterparty_node_id,
+                                                       channel_id: $funding_txo.to_channel_id(),
+                                               });
+                               }
                                if $peer_state.in_flight_monitor_updates.insert($funding_txo, $chan_in_flight_upds).is_some() {
                                        log_error!(args.logger, "Duplicate in-flight monitor update set for the same channel!");
                                        return Err(DecodeError::InvalidValue);
@@ -8913,6 +8965,12 @@ where
                                                                blocked_peer_state.lock().unwrap().actions_blocking_raa_monitor_updates
                                                                        .entry(blocked_channel_outpoint.to_channel_id())
                                                                        .or_insert_with(Vec::new).push(blocking_action.clone());
+                                                       } else {
+                                                               // If the channel we were blocking has closed, we don't need to
+                                                               // worry about it - the blocked monitor update should never have
+                                                               // been released from the `Channel` object so it can't have
+                                                               // completed, and if the channel closed there's no reason to bother
+                                                               // anymore.
                                                        }
                                                }
                                        }
@@ -9961,20 +10019,18 @@ mod tests {
                let node = create_network(1, &node_cfg, &node_chanmgr);
                let sender_intended_amt_msat = 100;
                let extra_fee_msat = 10;
-               let hop_data = msgs::OnionHopData {
-                       amt_to_forward: 100,
+               let hop_data = msgs::InboundOnionPayload::Receive {
+                       amt_msat: 100,
                        outgoing_cltv_value: 42,
-                       format: msgs::OnionHopDataFormat::FinalNode {
-                               keysend_preimage: None,
-                               payment_metadata: None,
-                               payment_data: Some(msgs::FinalOnionHopData {
-                                       payment_secret: PaymentSecret([0; 32]), total_msat: sender_intended_amt_msat,
-                               }),
-                       }
+                       payment_metadata: None,
+                       keysend_preimage: None,
+                       payment_data: Some(msgs::FinalOnionHopData {
+                               payment_secret: PaymentSecret([0; 32]), total_msat: sender_intended_amt_msat,
+                       }),
                };
                // Check that if the amount we received + the penultimate hop extra fee is less than the sender
                // intended amount, we fail the payment.
-               if let Err(crate::ln::channelmanager::ReceiveError { err_code, .. }) =
+               if let Err(crate::ln::channelmanager::InboundOnionErr { err_code, .. }) =
                        node[0].node.construct_recv_pending_htlc_info(hop_data, [0; 32], PaymentHash([0; 32]),
                                sender_intended_amt_msat - extra_fee_msat - 1, 42, None, true, Some(extra_fee_msat))
                {
@@ -9982,16 +10038,14 @@ mod tests {
                } else { panic!(); }
 
                // If amt_received + extra_fee is equal to the sender intended amount, we're fine.
-               let hop_data = msgs::OnionHopData { // This is the same hop_data as above, OnionHopData doesn't implement Clone
-                       amt_to_forward: 100,
+               let hop_data = msgs::InboundOnionPayload::Receive { // This is the same payload as above, InboundOnionPayload doesn't implement Clone
+                       amt_msat: 100,
                        outgoing_cltv_value: 42,
-                       format: msgs::OnionHopDataFormat::FinalNode {
-                               keysend_preimage: None,
-                               payment_metadata: None,
-                               payment_data: Some(msgs::FinalOnionHopData {
-                                       payment_secret: PaymentSecret([0; 32]), total_msat: sender_intended_amt_msat,
-                               }),
-                       }
+                       payment_metadata: None,
+                       keysend_preimage: None,
+                       payment_data: Some(msgs::FinalOnionHopData {
+                               payment_secret: PaymentSecret([0; 32]), total_msat: sender_intended_amt_msat,
+                       }),
                };
                assert!(node[0].node.construct_recv_pending_htlc_info(hop_data, [0; 32], PaymentHash([0; 32]),
                        sender_intended_amt_msat - extra_fee_msat, 42, None, true, Some(extra_fee_msat)).is_ok());