Return `ClosureReason` from `Channel` chain update methods
authorMatt Corallo <git@bluematt.me>
Thu, 30 Sep 2021 21:35:40 +0000 (21:35 +0000)
committerMatt Corallo <git@bluematt.me>
Tue, 16 Nov 2021 21:44:35 +0000 (21:44 +0000)
This fixes a few `ClosureReason`s and allows us to have
finer-grained user-visible errors when a channel closes due to an
on-chain event.

lightning/src/ln/channel.rs
lightning/src/ln/channelmanager.rs
lightning/src/ln/functional_test_utils.rs
lightning/src/ln/functional_tests.rs
lightning/src/ln/reorg_tests.rs
lightning/src/util/events.rs

index a921f68b90ef3a22ddfdc1b80872e3172198eaf6..8703f6c956589cdaa81c362772eeb9db01353735 100644 (file)
@@ -35,6 +35,7 @@ use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, LATENCY_GRACE_PERIOD_BLOCKS};
 use chain::transaction::{OutPoint, TransactionData};
 use chain::keysinterface::{Sign, KeysInterface};
+use util::events::ClosureReason;
 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
 use util::logger::Logger;
 use util::errors::APIError;
@@ -4117,7 +4118,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// In the first case, we store the confirmation height and calculating the short channel id.
        /// In the second, we simply return an Err indicating we need to be force-closed now.
        pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
-                       -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
+       -> Result<Option<msgs::FundingLocked>, ClosureReason> where L::Target: Logger {
                let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
                for &(index_in_block, tx) in txdata.iter() {
                        if let Some(funding_txo) = self.get_funding_txo() {
@@ -4138,10 +4139,8 @@ impl<Signer: Sign> Channel<Signer> {
                                                                panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
                                                        }
                                                        self.update_time_counter += 1;
-                                                       return Err(msgs::ErrorMessage {
-                                                               channel_id: self.channel_id(),
-                                                               data: "funding tx had wrong script/value or output index".to_owned()
-                                                       });
+                                                       let err_reason = "funding tx had wrong script/value or output index";
+                                                       return Err(ClosureReason::ProcessingError { err: err_reason.to_owned() });
                                                } else {
                                                        if self.is_outbound() {
                                                                for input in tx.input.iter() {
@@ -4172,10 +4171,7 @@ impl<Signer: Sign> Channel<Signer> {
                                for inp in tx.input.iter() {
                                        if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
                                                log_info!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
-                                               return Err(msgs::ErrorMessage {
-                                                       channel_id: self.channel_id(),
-                                                       data: "Commitment or closing transaction was confirmed on chain.".to_owned()
-                                               });
+                                               return Err(ClosureReason::CommitmentTxConfirmed);
                                        }
                                }
                        }
@@ -4195,7 +4191,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
        /// back.
        pub fn best_block_updated<L: Deref>(&mut self, height: u32, highest_header_time: u32, logger: &L)
-                       -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> where L::Target: Logger {
+       -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), ClosureReason> where L::Target: Logger {
                let mut timed_out_htlcs = Vec::new();
                // This mirrors the check in ChannelManager::decode_update_add_htlc_onion, refusing to
                // forward an HTLC when our counterparty should almost certainly just fail it for expiring
@@ -4236,10 +4232,9 @@ impl<Signer: Sign> Channel<Signer> {
                        // close the channel and hope we can get the latest state on chain (because presumably
                        // the funding transaction is at least still in the mempool of most nodes).
                        if funding_tx_confirmations < self.minimum_depth.unwrap() as i64 / 2 {
-                               return Err(msgs::ErrorMessage {
-                                       channel_id: self.channel_id(),
-                                       data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth.unwrap(), funding_tx_confirmations),
-                               });
+                               let err_reason = format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.",
+                                       self.minimum_depth.unwrap(), funding_tx_confirmations);
+                               return Err(ClosureReason::ProcessingError { err: err_reason });
                        }
                }
 
@@ -4249,7 +4244,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// Indicates the funding transaction is no longer confirmed in the main chain. This may
        /// force-close the channel, but may also indicate a harmless reorganization of a block or two
        /// before the channel has reached funding_locked and we can just wait for more blocks.
-       pub fn funding_transaction_unconfirmed<L: Deref>(&mut self, logger: &L) -> Result<(), msgs::ErrorMessage> where L::Target: Logger {
+       pub fn funding_transaction_unconfirmed<L: Deref>(&mut self, logger: &L) -> Result<(), ClosureReason> where L::Target: Logger {
                if self.funding_tx_confirmation_height != 0 {
                        // We handle the funding disconnection by calling best_block_updated with a height one
                        // below where our funding was connected, implying a reorg back to conf_height - 1.
index 631edfe6cf375bd1f419d7b949b9cd728a100621..a6c319b6e9f78bd4b18aa3ce1bd17e59d414f0bc 100644 (file)
@@ -4850,7 +4850,7 @@ where
        /// Calls a function which handles an on-chain event (blocks dis/connected, transactions
        /// un/confirmed, etc) on each channel, handling any resulting errors or messages generated by
        /// the function.
-       fn do_chain_event<FN: Fn(&mut Channel<Signer>) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage>>
+       fn do_chain_event<FN: Fn(&mut Channel<Signer>) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), ClosureReason>>
                        (&self, height_opt: Option<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.
@@ -4895,7 +4895,7 @@ where
                                                }
                                                short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
                                        }
-                               } else if let Err(e) = res {
+                               } else if let Err(reason) = res {
                                        if let Some(short_id) = channel.get_short_channel_id() {
                                                short_to_id.remove(&short_id);
                                        }
@@ -4907,10 +4907,14 @@ where
                                                        msg: update
                                                });
                                        }
-                                       self.issue_channel_close_events(channel, ClosureReason::CommitmentTxConfirmed);
+                                       let reason_message = format!("{}", reason);
+                                       self.issue_channel_close_events(channel, reason);
                                        pending_msg_events.push(events::MessageSendEvent::HandleError {
                                                node_id: channel.get_counterparty_node_id(),
-                                               action: msgs::ErrorAction::SendErrorMessage { msg: e },
+                                               action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
+                                                       channel_id: channel.channel_id(),
+                                                       data: reason_message,
+                                               } },
                                        });
                                        return false;
                                }
index e6b2467077422a974eff3657c1ae6a2d0c615f97..e9e36e607ec45950dc4ebadab6a8c940c756f114 100644 (file)
@@ -1737,7 +1737,7 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
 }
 
 pub fn get_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, 'b, 'c>>, a: usize, b: usize)  {
-       handle_announce_close_broadcast_events(nodes, a, b, false, "Commitment or closing transaction was confirmed on chain.");
+       handle_announce_close_broadcast_events(nodes, a, b, false, "Channel closed because commitment or closing transaction was confirmed on chain.");
 }
 
 #[cfg(test)]
index 118bb1497d8f20a833a2c7273e56a25c81b4dea7..b6b3d345eb7dca3fc0d8d7d6e953bac2ee3365fa 100644 (file)
@@ -1207,7 +1207,7 @@ fn test_duplicate_htlc_different_direction_onchain() {
                        MessageSendEvent::BroadcastChannelUpdate { .. } => {},
                        MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
                                assert_eq!(node_id, nodes[1].node.get_our_node_id());
-                               assert_eq!(msg.data, "Commitment or closing transaction was confirmed on chain.");
+                               assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
                        },
                        MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
                                assert!(update_add_htlcs.is_empty());
@@ -3017,7 +3017,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
        match events[if deliver_bs_raa { 2 } else { 1 }] {
                MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
                        assert_eq!(channel_id, chan_2.2);
-                       assert_eq!(data.as_str(), "Commitment or closing transaction was confirmed on chain.");
+                       assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
                },
                _ => panic!("Unexpected event"),
        }
@@ -8831,15 +8831,16 @@ fn test_invalid_funding_tx() {
        assert_eq!(nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap()[0], tx);
        nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().clear();
 
+       let expected_err = "funding tx had wrong script/value or output index";
        confirm_transaction_at(&nodes[1], &tx, 1);
-       check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
+       check_closed_event!(nodes[1], 1, ClosureReason::ProcessingError { err: expected_err.to_string() });
        check_added_monitors!(nodes[1], 1);
        let events_2 = nodes[1].node.get_and_clear_pending_msg_events();
        assert_eq!(events_2.len(), 1);
        if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
                assert_eq!(*node_id, nodes[0].node.get_our_node_id());
                if let msgs::ErrorAction::SendErrorMessage { msg } = action {
-                       assert_eq!(msg.data, "funding tx had wrong script/value or output index");
+                       assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
                } else { panic!(); }
        } else { panic!(); }
        assert_eq!(nodes[1].node.list_channels().len(), 0);
index a9b341b34ebe22db16fbe6df14bd7f2b0ba13870..5cd1a890c49d5d12c6438b7369121d579045609c 100644 (file)
@@ -219,9 +219,9 @@ fn do_test_unconf_chan(reload_node: bool, reorg_after_reload: bool, use_funding_
                        disconnect_all_blocks(&nodes[0]);
                }
                if connect_style == ConnectStyle::FullBlockViaListen && !use_funding_unconfirmed {
-                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Funding transaction was un-confirmed. Locked at 6 confs, now have 2 confs.");
+                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Channel closed because of an exception: Funding transaction was un-confirmed. Locked at 6 confs, now have 2 confs.");
                } else {
-                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Funding transaction was un-confirmed. Locked at 6 confs, now have 0 confs.");
+                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Channel closed because of an exception: Funding transaction was un-confirmed. Locked at 6 confs, now have 0 confs.");
                }
                check_added_monitors!(nodes[1], 1);
                {
@@ -287,9 +287,9 @@ fn do_test_unconf_chan(reload_node: bool, reorg_after_reload: bool, use_funding_
                        disconnect_all_blocks(&nodes[0]);
                }
                if connect_style == ConnectStyle::FullBlockViaListen && !use_funding_unconfirmed {
-                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Funding transaction was un-confirmed. Locked at 6 confs, now have 2 confs.");
+                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Channel closed because of an exception: Funding transaction was un-confirmed. Locked at 6 confs, now have 2 confs.");
                } else {
-                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Funding transaction was un-confirmed. Locked at 6 confs, now have 0 confs.");
+                       handle_announce_close_broadcast_events(&nodes, 0, 1, true, "Channel closed because of an exception: Funding transaction was un-confirmed. Locked at 6 confs, now have 0 confs.");
                }
                check_added_monitors!(nodes[1], 1);
                {
@@ -303,12 +303,13 @@ fn do_test_unconf_chan(reload_node: bool, reorg_after_reload: bool, use_funding_
        *nodes[0].chain_monitor.expect_channel_force_closed.lock().unwrap() = Some((chan.2, true));
        nodes[0].node.test_process_background_events(); // Required to free the pending background monitor update
        check_added_monitors!(nodes[0], 1);
-       check_closed_event!(nodes[0], 1, ClosureReason::CommitmentTxConfirmed);
-       if connect_style == ConnectStyle::FullBlockViaListen && !use_funding_unconfirmed {
-               check_closed_event!(nodes[1], 1, ClosureReason::CounterpartyForceClosed { peer_msg: "Funding transaction was un-confirmed. Locked at 6 confs, now have 2 confs.".to_string() });
+       let expected_err = if connect_style == ConnectStyle::FullBlockViaListen && !use_funding_unconfirmed {
+               "Funding transaction was un-confirmed. Locked at 6 confs, now have 2 confs."
        } else {
-               check_closed_event!(nodes[1], 1, ClosureReason::CounterpartyForceClosed { peer_msg: "Funding transaction was un-confirmed. Locked at 6 confs, now have 0 confs.".to_string() });
-       }
+               "Funding transaction was un-confirmed. Locked at 6 confs, now have 0 confs."
+       };
+       check_closed_event!(nodes[1], 1, ClosureReason::CounterpartyForceClosed { peer_msg: "Channel closed because of an exception: ".to_owned() + expected_err });
+       check_closed_event!(nodes[0], 1, ClosureReason::ProcessingError { err: expected_err.to_owned() });
        assert_eq!(nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().len(), 1);
        nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().clear();
 
index e0f0a63dbb341d8507a80ecd07b4a94f3cb91699..c021fe3c16b9dda30f7b8a75189d3785323fe2a2 100644 (file)
@@ -118,6 +118,27 @@ pub enum ClosureReason {
        OutdatedChannelManager
 }
 
+impl core::fmt::Display for ClosureReason {
+       fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
+               f.write_str("Channel closed because ")?;
+               match self {
+                       ClosureReason::CounterpartyForceClosed { peer_msg } => {
+                               f.write_str("counterparty force-closed with message ")?;
+                               f.write_str(&peer_msg)
+                       },
+                       ClosureReason::HolderForceClosed => f.write_str("user manually force-closed the channel"),
+                       ClosureReason::CooperativeClosure => f.write_str("the channel was cooperatively closed"),
+                       ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
+                       ClosureReason::ProcessingError { err } => {
+                               f.write_str("of an exception: ")?;
+                               f.write_str(&err)
+                       },
+                       ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
+                       ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
+               }
+       }
+}
+
 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
        (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
        (2, HolderForceClosed) => {},