From ba6eee24e4e07d5736f4612f6fe7262da0fff4df Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Thu, 25 Feb 2021 21:55:30 -0500 Subject: [PATCH] Change ShutdownResult type to better capture the possibilites The return value from Channel::force_shutdown previously always returned a `ChannelMonitorUpdate`, but expected it to only be applied in the case that it *also* returned a Some for the funding transaction output. This is confusing, instead we move the `ChannelMontiorUpdate` inside the Option, making it hold a tuple instead. --- lightning/src/ln/channel.rs | 16 ++++++++-------- lightning/src/ln/channelmanager.rs | 10 +++++----- 2 files changed, 13 insertions(+), 13 deletions(-) diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index 63365222..16d1a0f8 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -4179,7 +4179,7 @@ impl Channel { /// those explicitly stated to be allowed after shutdown completes, eg some simple getters). /// Also returns the list of payment_hashes for channels which we can safely fail backwards /// immediately (others we will have to allow to time out). - pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>) { + pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) { assert!(self.channel_state != ChannelState::ShutdownComplete as u32); // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and @@ -4193,7 +4193,7 @@ impl Channel { _ => {} } } - let funding_txo = if let Some(funding_txo) = self.get_funding_txo() { + let monitor_update = if let Some(funding_txo) = self.get_funding_txo() { // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent), // returning a channel monitor update here would imply a channel monitor update before // we even registered the channel monitor to begin with, which is invalid. @@ -4202,17 +4202,17 @@ impl Channel { // monitor update to the user, even if we return one). // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more. if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 { - Some(funding_txo.clone()) + self.latest_monitor_update_id += 1; + Some((funding_txo, ChannelMonitorUpdate { + update_id: self.latest_monitor_update_id, + updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }], + })) } else { None } } else { None }; self.channel_state = ChannelState::ShutdownComplete as u32; self.update_time_counter += 1; - self.latest_monitor_update_id += 1; - (funding_txo, ChannelMonitorUpdate { - update_id: self.latest_monitor_update_id, - updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }], - }, dropped_outbound_htlcs) + (monitor_update, dropped_outbound_htlcs) } } diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs index 893cb4b3..4ac2833d 100644 --- a/lightning/src/ln/channelmanager.rs +++ b/lightning/src/ln/channelmanager.rs @@ -206,7 +206,7 @@ pub struct PaymentPreimage(pub [u8;32]); #[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)] pub struct PaymentSecret(pub [u8;32]); -type ShutdownResult = (Option, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>); +type ShutdownResult = (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>); /// Error type returned across the channel_state mutex boundary. When an Err is generated for a /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel @@ -942,12 +942,12 @@ impl ChannelMana #[inline] fn finish_force_close_channel(&self, shutdown_res: ShutdownResult) { - let (funding_txo_option, monitor_update, mut failed_htlcs) = shutdown_res; + let (monitor_update_option, mut failed_htlcs) = shutdown_res; log_trace!(self.logger, "Finishing force-closure of channel {} HTLCs to fail", failed_htlcs.len()); for htlc_source in failed_htlcs.drain(..) { self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_source.0, &htlc_source.1, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() }); } - if let Some(funding_txo) = funding_txo_option { + if let Some((funding_txo, monitor_update)) = monitor_update_option { // There isn't anything we can do if we get an update failure - we're already // force-closing. The monitor update on the required in-memory copy should broadcast // the latest local state, which is the best we can do anyway. Thus, it is safe to @@ -2418,7 +2418,7 @@ impl ChannelMana // We do not do a force-close here as that would generate a monitor update for // a monitor that we didn't manage to store (and that we don't care about - we // don't respond with the funding_signed so the channel can never go on chain). - let (_funding_txo_option, _monitor_update, failed_htlcs) = chan.force_shutdown(true); + let (_monitor_update, failed_htlcs) = chan.force_shutdown(true); assert!(failed_htlcs.is_empty()); return Err(MsgHandleErrInternal::send_err_msg_no_close("ChannelMonitor storage failure".to_owned(), funding_msg.channel_id)); }, @@ -4071,7 +4071,7 @@ impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> channel.get_cur_counterparty_commitment_transaction_number() > monitor.get_cur_counterparty_commitment_number() || channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() { // But if the channel is behind of the monitor, close the channel: - let (_, _, mut new_failed_htlcs) = channel.force_shutdown(true); + let (_, mut new_failed_htlcs) = channel.force_shutdown(true); failed_htlcs.append(&mut new_failed_htlcs); monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger); } else { -- 2.30.2