From 93011c377c1b6c73a0e93f63669ecf95be18522c Mon Sep 17 00:00:00 2001
From: Matt Corallo <git@bluematt.me>
Date: Mon, 6 May 2024 00:02:09 +0000
Subject: [PATCH] Allow `ChannelError` to specify the `ClosureReason`

This will allow us to add more granular failure reasons when
returning the general `ChannelError::Close`.
---
 lightning/src/ln/channel.rs          |  8 ++++----
 lightning/src/ln/channelmanager.rs   |  8 +++-----
 lightning/src/ln/functional_tests.rs | 10 ++++++++--
 3 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index 37ce1082e..c1294af6a 100644
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -710,7 +710,7 @@ pub const MIN_THEIR_CHAN_RESERVE_SATOSHIS: u64 = 1000;
 pub(super) enum ChannelError {
 	Ignore(String),
 	Warn(String),
-	Close(String),
+	Close((String, ClosureReason)),
 }
 
 impl fmt::Debug for ChannelError {
@@ -718,7 +718,7 @@ impl fmt::Debug for ChannelError {
 		match self {
 			&ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
 			&ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
-			&ChannelError::Close(ref e) => write!(f, "Close : {}", e),
+			&ChannelError::Close((ref e, _)) => write!(f, "Close : {}", e),
 		}
 	}
 }
@@ -728,14 +728,14 @@ impl fmt::Display for ChannelError {
 		match self {
 			&ChannelError::Ignore(ref e) => write!(f, "{}", e),
 			&ChannelError::Warn(ref e) => write!(f, "{}", e),
-			&ChannelError::Close(ref e) => write!(f, "{}", e),
+			&ChannelError::Close((ref e, _)) => write!(f, "{}", e),
 		}
 	}
 }
 
 impl ChannelError {
 	pub(super) fn close(err: String) -> Self {
-		ChannelError::Close(err.clone())
+		ChannelError::Close((err.clone(), ClosureReason::ProcessingError { err }))
 	}
 }
 
diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index d1a8672c5..a2647c80c 100644
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -636,7 +636,7 @@ impl MsgHandleErrInternal {
 					err: msg,
 					action: msgs::ErrorAction::IgnoreError,
 				},
-				ChannelError::Close(msg) => LightningError {
+				ChannelError::Close((msg, _reason)) => LightningError {
 					err: msg.clone(),
 					action: msgs::ErrorAction::SendErrorMessage {
 						msg: msgs::ErrorMessage {
@@ -2446,11 +2446,10 @@ macro_rules! convert_chan_phase_err {
 			ChannelError::Ignore(msg) => {
 				(false, MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore(msg), *$channel_id))
 			},
-			ChannelError::Close(msg) => {
+			ChannelError::Close((msg, reason)) => {
 				let logger = WithChannelContext::from(&$self.logger, &$channel.context, None);
 				log_error!(logger, "Closing channel {} due to close-required error: {}", $channel_id, msg);
 				update_maps_on_chan_removal!($self, $channel.context);
-				let reason = ClosureReason::ProcessingError { err: msg.clone() };
 				let shutdown_res = $channel.context.force_shutdown(true, reason);
 				let err =
 					MsgHandleErrInternal::from_finish_shutdown(msg, *$channel_id, shutdown_res, $channel_update);
@@ -4201,10 +4200,9 @@ where
 			Some(ChannelPhase::UnfundedOutboundV1(mut chan)) => {
 				macro_rules! close_chan { ($err: expr, $api_err: expr, $chan: expr) => { {
 					let counterparty;
-					let err = if let ChannelError::Close(msg) = $err {
+					let err = if let ChannelError::Close((msg, reason)) = $err {
 						let channel_id = $chan.context.channel_id();
 						counterparty = chan.context.get_counterparty_node_id();
-						let reason = ClosureReason::ProcessingError { err: msg.clone() };
 						let shutdown_res = $chan.context.force_shutdown(false, reason);
 						MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, shutdown_res, None)
 					} else { unreachable!(); };
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 7cd0f376d..5c9d8f269 100644
--- a/lightning/src/ln/functional_tests.rs
+++ b/lightning/src/ln/functional_tests.rs
@@ -7263,7 +7263,10 @@ fn test_user_configurable_csv_delay() {
 		&low_our_to_self_config, 0, &nodes[0].logger, /*is_0conf=*/false)
 	{
 		match error {
-			ChannelError::Close(err) => { assert!(regex::Regex::new(r"Configured with an unreasonable our_to_self_delay \(\d+\) putting user funds at risks").unwrap().is_match(err.as_str()));  },
+			ChannelError::Close((err, _)) => {
+				let regex = regex::Regex::new(r"Configured with an unreasonable our_to_self_delay \(\d+\) putting user funds at risks").unwrap();
+				assert!(regex.is_match(err.as_str()));
+			},
 			_ => panic!("Unexpected event"),
 		}
 	} else { assert!(false); }
@@ -7295,7 +7298,10 @@ fn test_user_configurable_csv_delay() {
 		&high_their_to_self_config, 0, &nodes[0].logger, /*is_0conf=*/false)
 	{
 		match error {
-			ChannelError::Close(err) => { assert!(regex::Regex::new(r"They wanted our payments to be delayed by a needlessly long period\. Upper limit: \d+\. Actual: \d+").unwrap().is_match(err.as_str())); },
+			ChannelError::Close((err, _)) => {
+				let regex = regex::Regex::new(r"They wanted our payments to be delayed by a needlessly long period\. Upper limit: \d+\. Actual: \d+").unwrap();
+				assert!(regex.is_match(err.as_str()));
+			},
 			_ => panic!("Unexpected event"),
 		}
 	} else { assert!(false); }
-- 
2.39.5