Merge pull request #838 from TheBlueMatt/2021-03-skip-blocks
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 19fdd97a65a586fabb9a22b2f482dca995facf97..efb2fe9c37bd9a8ec2c9a36d9a521072a6f8c6f3 100644 (file)
@@ -1004,16 +1004,14 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
        }
 
-       fn force_close_channel_with_peer(&self, channel_id: &[u8; 32], peer_node_id: Option<&PublicKey>) -> Result<(), APIError> {
+       fn force_close_channel_with_peer(&self, channel_id: &[u8; 32], peer_node_id: Option<&PublicKey>) -> Result<PublicKey, APIError> {
                let mut chan = {
                        let mut channel_state_lock = self.channel_state.lock().unwrap();
                        let channel_state = &mut *channel_state_lock;
                        if let hash_map::Entry::Occupied(chan) = channel_state.by_id.entry(channel_id.clone()) {
                                if let Some(node_id) = peer_node_id {
                                        if chan.get().get_counterparty_node_id() != *node_id {
-                                               // Error or Ok here doesn't matter - the result is only exposed publicly
-                                               // when peer_node_id is None anyway.
-                                               return Ok(());
+                                               return Err(APIError::ChannelUnavailable{err: "No such channel".to_owned()});
                                        }
                                }
                                if let Some(short_id) = chan.get().get_short_channel_id() {
@@ -1033,14 +1031,27 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        });
                }
 
-               Ok(())
+               Ok(chan.get_counterparty_node_id())
        }
 
        /// Force closes a channel, immediately broadcasting the latest local commitment transaction to
        /// the chain and rejecting new HTLCs on the given channel. Fails if channel_id is unknown to the manager.
        pub fn force_close_channel(&self, channel_id: &[u8; 32]) -> Result<(), APIError> {
                let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
-               self.force_close_channel_with_peer(channel_id, None)
+               match self.force_close_channel_with_peer(channel_id, None) {
+                       Ok(counterparty_node_id) => {
+                               self.channel_state.lock().unwrap().pending_msg_events.push(
+                                       events::MessageSendEvent::HandleError {
+                                               node_id: counterparty_node_id,
+                                               action: msgs::ErrorAction::SendErrorMessage {
+                                                       msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+                                               },
+                                       }
+                               );
+                               Ok(())
+                       },
+                       Err(e) => Err(e)
+               }
        }
 
        /// Force close all channels, immediately broadcasting the latest local commitment transaction
@@ -3196,6 +3207,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                        msg: update
                                                                });
                                                        }
+                                                       pending_msg_events.push(events::MessageSendEvent::HandleError {
+                                                               node_id: chan.get_counterparty_node_id(),
+                                                               action: msgs::ErrorAction::SendErrorMessage {
+                                                                       msg: msgs::ErrorMessage { channel_id: chan.channel_id(), data: "Channel force-closed".to_owned() }
+                                                               },
+                                                       });
                                                }
                                        },
                                }
@@ -3278,12 +3295,26 @@ where
        L::Target: Logger,
 {
        fn block_connected(&self, block: &Block, height: u32) {
+               assert_eq!(*self.last_block_hash.read().unwrap(), block.header.prev_blockhash,
+                       "Blocks must be connected in chain-order - the connected header must build on the last connected header");
+               assert_eq!(self.latest_block_height.load(Ordering::Acquire) as u64, height as u64 - 1,
+                       "Blocks must be connected in chain-order - the connected block height must be one greater than the previous height");
                let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
-               ChannelManager::block_connected(self, &block.header, &txdata, height);
+               self.transactions_confirmed(&block.header, height, &txdata);
+               self.update_best_block(&block.header, height);
        }
 
-       fn block_disconnected(&self, header: &BlockHeader, _height: u32) {
-               ChannelManager::block_disconnected(self, header);
+       fn block_disconnected(&self, header: &BlockHeader, height: u32) {
+               assert_eq!(*self.last_block_hash.read().unwrap(), header.block_hash(),
+                       "Blocks must be disconnected in chain-order - the disconnected header must be the last connected header");
+
+               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               let new_height = self.latest_block_height.fetch_sub(1, Ordering::AcqRel) as u32 - 1;
+               assert_eq!(new_height, height - 1,
+                       "Blocks must be disconnected in chain-order - the disconnected block must have the correct height");
+               *self.last_block_hash.write().unwrap() = header.prev_blockhash;
+
+               self.do_chain_event(new_height, |channel| channel.update_best_block(new_height, header.time));
        }
 }
 
@@ -3294,22 +3325,11 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
-       /// Updates channel state based on transactions seen in a connected block.
-       pub fn block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
+       fn do_chain_event<FN: Fn(&mut Channel<Signer>) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage>>
+                       (&self, height: u32, f: FN) {
                // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
                // during initialization prior to the chain_monitor being fully configured in some cases.
                // See the docs for `ChannelManagerReadArgs` for more.
-               let block_hash = header.block_hash();
-               log_trace!(self.logger, "Block {} at height {} connected", block_hash, height);
-
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
-
-               assert_eq!(*self.last_block_hash.read().unwrap(), header.prev_blockhash,
-                       "Blocks must be connected in chain-order - the connected header must build on the last connected header");
-               assert_eq!(self.latest_block_height.load(Ordering::Acquire) as u64, height as u64 - 1,
-                       "Blocks must be connected in chain-order - the connected header must build on the last connected header");
-               self.latest_block_height.store(height as usize, Ordering::Release);
-               *self.last_block_hash.write().unwrap() = block_hash;
 
                let mut failed_channels = Vec::new();
                let mut timed_out_htlcs = Vec::new();
@@ -3319,7 +3339,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        let short_to_id = &mut channel_state.short_to_id;
                        let pending_msg_events = &mut channel_state.pending_msg_events;
                        channel_state.by_id.retain(|_, channel| {
-                               let res = channel.block_connected(header, txdata, height);
+                               let res = f(channel);
                                if let Ok((chan_res, mut timed_out_pending_htlcs)) = res {
                                        for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
                                                let chan_update = self.get_channel_update(&channel).map(|u| u.encode_with_len()).unwrap(); // Cannot add/recv HTLCs before we have a short_id so unwrap is safe
@@ -3345,32 +3365,23 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
                                        }
                                } else if let Err(e) = res {
+                                       if let Some(short_id) = channel.get_short_channel_id() {
+                                               short_to_id.remove(&short_id);
+                                       }
+                                       // It looks like our counterparty went on-chain or funding transaction was
+                                       // reorged out of the main chain. Close the channel.
+                                       failed_channels.push(channel.force_shutdown(true));
+                                       if let Ok(update) = self.get_channel_update(&channel) {
+                                               pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
+                                                       msg: update
+                                               });
+                                       }
                                        pending_msg_events.push(events::MessageSendEvent::HandleError {
                                                node_id: channel.get_counterparty_node_id(),
                                                action: msgs::ErrorAction::SendErrorMessage { msg: e },
                                        });
                                        return false;
                                }
-                               if let Some(funding_txo) = channel.get_funding_txo() {
-                                       for &(_, tx) in txdata.iter() {
-                                               for inp in tx.input.iter() {
-                                                       if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
-                                                               log_trace!(self.logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(channel.channel_id()));
-                                                               if let Some(short_id) = channel.get_short_channel_id() {
-                                                                       short_to_id.remove(&short_id);
-                                                               }
-                                                               // It looks like our counterparty went on-chain. Close the channel.
-                                                               failed_channels.push(channel.force_shutdown(true));
-                                                               if let Ok(update) = self.get_channel_update(&channel) {
-                                                                       pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                                               msg: update
-                                                                       });
-                                                               }
-                                                               return false;
-                                                       }
-                                               }
-                                       }
-                               }
                                true
                        });
 
@@ -3399,6 +3410,64 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {
                        self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
                }
+       }
+
+       /// Updates channel state to take note of transactions which were confirmed in the given block
+       /// at the given height.
+       ///
+       /// Note that you must still call (or have called) [`update_best_block`] with the block
+       /// information which is included here.
+       ///
+       /// This method may be called before or after [`update_best_block`] for a given block's
+       /// transaction data and may be called multiple times with additional transaction data for a
+       /// given block.
+       ///
+       /// This method may be called for a previous block after an [`update_best_block`] call has
+       /// been made for a later block, however it must *not* be called with transaction data from a
+       /// block which is no longer in the best chain (ie where [`update_best_block`] has already
+       /// been informed about a blockchain reorganization which no longer includes the block which
+       /// corresponds to `header`).
+       ///
+       /// [`update_best_block`]: `Self::update_best_block`
+       pub fn transactions_confirmed(&self, header: &BlockHeader, height: u32, txdata: &TransactionData) {
+               // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
+               // during initialization prior to the chain_monitor being fully configured in some cases.
+               // See the docs for `ChannelManagerReadArgs` for more.
+
+               let block_hash = header.block_hash();
+               log_trace!(self.logger, "{} transactions included in block {} at height {} provided", txdata.len(), block_hash, height);
+
+               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+               self.do_chain_event(height, |channel| channel.transactions_confirmed(&block_hash, height, txdata, &self.logger).map(|a| (a, Vec::new())));
+       }
+
+       /// Updates channel state with the current best blockchain tip. You should attempt to call this
+       /// quickly after a new block becomes available, however if multiple new blocks become
+       /// available at the same time, only a single `update_best_block()` call needs to be made.
+       ///
+       /// This method should also be called immediately after any block disconnections, once at the
+       /// reorganization fork point, and once with the new chain tip. Calling this method at the
+       /// blockchain reorganization fork point ensures we learn when a funding transaction which was
+       /// previously confirmed is reorganized out of the blockchain, ensuring we do not continue to
+       /// accept payments which cannot be enforced on-chain.
+       ///
+       /// In both the block-connection and block-disconnection case, this method may be called either
+       /// once per block connected or disconnected, or simply at the fork point and new tip(s),
+       /// skipping any intermediary blocks.
+       pub fn update_best_block(&self, header: &BlockHeader, height: u32) {
+               // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
+               // during initialization prior to the chain_monitor being fully configured in some cases.
+               // See the docs for `ChannelManagerReadArgs` for more.
+
+               let block_hash = header.block_hash();
+               log_trace!(self.logger, "New best block: {} at height {}", block_hash, height);
+
+               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
+
+               self.latest_block_height.store(height as usize, Ordering::Release);
+               *self.last_block_hash.write().unwrap() = block_hash;
+
+               self.do_chain_event(height, |channel| channel.update_best_block(height, header.time));
 
                loop {
                        // Update last_node_announcement_serial to be the max of its current value and the
@@ -3414,48 +3483,6 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
        }
 
-       /// Updates channel state based on a disconnected block.
-       ///
-       /// If necessary, the channel may be force-closed without letting the counterparty participate
-       /// in the shutdown.
-       pub fn block_disconnected(&self, header: &BlockHeader) {
-               // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
-               // during initialization prior to the chain_monitor being fully configured in some cases.
-               // See the docs for `ChannelManagerReadArgs` for more.
-               let _persistence_guard = PersistenceNotifierGuard::new(&self.total_consistency_lock, &self.persistence_notifier);
-
-               assert_eq!(*self.last_block_hash.read().unwrap(), header.block_hash(),
-                       "Blocks must be disconnected in chain-order - the disconnected header must be the last connected header");
-               self.latest_block_height.fetch_sub(1, Ordering::AcqRel);
-               *self.last_block_hash.write().unwrap() = header.prev_blockhash;
-
-               let mut failed_channels = Vec::new();
-               {
-                       let mut channel_lock = self.channel_state.lock().unwrap();
-                       let channel_state = &mut *channel_lock;
-                       let short_to_id = &mut channel_state.short_to_id;
-                       let pending_msg_events = &mut channel_state.pending_msg_events;
-                       channel_state.by_id.retain(|_,  v| {
-                               if v.block_disconnected(header) {
-                                       if let Some(short_id) = v.get_short_channel_id() {
-                                               short_to_id.remove(&short_id);
-                                       }
-                                       failed_channels.push(v.force_shutdown(true));
-                                       if let Ok(update) = self.get_channel_update(&v) {
-                                               pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                       msg: update
-                                               });
-                                       }
-                                       false
-                               } else {
-                                       true
-                               }
-                       });
-               }
-
-               self.handle_init_event_channel_failures(failed_channels);
-       }
-
        /// Blocks until ChannelManager needs to be persisted or a timeout is reached. It returns a bool
        /// indicating whether persistence is necessary. Only one listener on
        /// `await_persistable_update` or `await_persistable_update_timeout` is guaranteed to be woken