From 7d1a43d5d5a41ffec9d87629e04d102e2becfadd Mon Sep 17 00:00:00 2001
From: Dusty Daemon <dustinpaystaxes@gmail.com>
Date: Fri, 4 Oct 2024 15:05:55 -0400
Subject: [PATCH] channeld: Fix `tx_abort` encoding

Switch to using same message format for `tx_abort` that wire_error and wire_warning use.

Changelog-None
---
 channeld/channeld.c        | 17 +++++++++++++----
 channeld/channeld_wire.csv |  2 +-
 common/wire_error.c        | 37 +++++++++++++++++++++++++++++++++++++
 common/wire_error.h        | 24 ++++++++++++++++++++++++
 4 files changed, 75 insertions(+), 5 deletions(-)

diff --git a/channeld/channeld.c b/channeld/channeld.c
index 923450044..baf8ebb56 100644
--- a/channeld/channeld.c
+++ b/channeld/channeld.c
@@ -1709,7 +1709,8 @@ static void check_tx_abort(struct peer *peer, const u8 *msg)
 	struct inflight *inflight = last_inflight(peer);
 	struct bitcoin_outpoint *outpoint;
 	struct channel_id channel_id;
-	u8 *reason;
+	u8 *data;
+	char *reason;
 
 	if (fromwire_peektype(msg) != WIRE_TX_ABORT)
 		return;
@@ -1721,7 +1722,7 @@ static void check_tx_abort(struct peer *peer, const u8 *msg)
 			        tal_hex(tmpctx, msg));
 	}
 
-	if (!fromwire_tx_abort(tmpctx, msg, &channel_id, &reason))
+	if (!fromwire_tx_abort(tmpctx, msg, &channel_id, &data))
 		peer_failed_warn(peer->pps, &peer->channel_id,
 				 "bad tx_abort %s", tal_hex(msg, msg));
 
@@ -1736,10 +1737,17 @@ static void check_tx_abort(struct peer *peer, const u8 *msg)
 
 	status_info("Send tx_abort to master");
 
+	reason = sanitize_error(tmpctx, msg, &peer->channel_id);
+
+	status_info("Peer initiated tx_abort for reason: %s", reason);
+
 	wire_sync_write(MASTER_FD,
 			take(towire_channeld_splice_abort(NULL, false,
 							  outpoint,
-							  (char*)reason)));
+							  tal_fmt(tmpctx,
+							  "Peer aborted"
+							  " for reason: %s",
+							  reason))));
 
 	/* Give master a chance to pass the fd along */
 	status_info("Delaying closing of master fd by 1 second");
@@ -1769,7 +1777,8 @@ static void splice_abort(struct peer *peer, const char *fmt, ...)
 	status_info("We are initiating tx_abort for reason: %s", reason);
 
 	peer_write(peer->pps,
-		   take(towire_tx_abort(NULL, &peer->channel_id, (u8*)reason)));
+		   take(towire_abortfmt(NULL, &peer->channel_id, "%s",
+		   			 reason)));
 
 	do {
 		msg = peer_read(tmpctx, peer->pps);
diff --git a/channeld/channeld_wire.csv b/channeld/channeld_wire.csv
index 592a8b65a..0f05342b1 100644
--- a/channeld/channeld_wire.csv
+++ b/channeld/channeld_wire.csv
@@ -287,7 +287,7 @@ msgdata,channeld_splice_state_error,state_error,wirestring,
 msgtype,channeld_splice_abort,7223
 msgdata,channeld_splice_abort,did_i_initiate,bool,
 msgdata,channeld_splice_abort,inflight_outpoint,?bitcoin_outpoint,
-msgdata,channeld_splice_abort,reason,?wirestring,
+msgdata,channeld_splice_abort,reason,wirestring,
 
 # master->channeld: Please enter stfu mode
 msgtype,channeld_stfu,7224
diff --git a/common/wire_error.c b/common/wire_error.c
index 97e121ee7..512a1cf6b 100644
--- a/common/wire_error.c
+++ b/common/wire_error.c
@@ -72,6 +72,43 @@ u8 *towire_warningfmt(const tal_t *ctx,
 	return msg;
 }
 
+u8 *towire_abortfmtv(const tal_t *ctx,
+		     const struct channel_id *channel,
+		     const char *fmt,
+		     va_list ap)
+{
+	/* BOLT #1:
+	 *
+	 * The channel is referred to by `channel_id`, unless `channel_id` is
+	 * 0 (i.e. all bytes are 0), in which case it refers to all
+	 * channels. */
+	static const struct channel_id all_channels;
+	char *estr;
+	u8 *msg;
+
+	estr = tal_vfmt(ctx, fmt, ap);
+	/* We need tal_len to work, so we use copy. */
+	msg = towire_tx_abort(ctx, channel ? channel : &all_channels,
+			      (u8 *)tal_dup_arr(estr, char, estr, strlen(estr), 0));
+	tal_free(estr);
+
+	return msg;
+}
+
+u8 *towire_abortfmt(const tal_t *ctx,
+		    const struct channel_id *channel,
+		    const char *fmt, ...)
+{
+	va_list ap;
+	u8 *msg;
+
+	va_start(ap, fmt);
+	msg = towire_abortfmtv(ctx, channel, fmt, ap);
+	va_end(ap);
+
+	return msg;
+}
+
 bool channel_id_is_all(const struct channel_id *channel_id)
 {
 	return memeqzero(channel_id, sizeof(*channel_id));
diff --git a/common/wire_error.h b/common/wire_error.h
index 7797295bb..6fe932513 100644
--- a/common/wire_error.h
+++ b/common/wire_error.h
@@ -54,6 +54,30 @@ u8 *towire_warningfmtv(const tal_t *ctx,
 		       const char *fmt,
 		       va_list ap);
 
+/**
+ * towire_abortfmt - helper to turn string into WIRE_TX_ABORT.
+ *
+ * @ctx: context to allocate from
+ * @channel: specific channel to complain about, or NULL for all.
+ * @fmt: format for warning.
+ */
+u8 *towire_abortfmt(const tal_t *ctx,
+		    const struct channel_id *channel,
+		    const char *fmt, ...) PRINTF_FMT(3,4);
+
+/**
+ * towire_abortfmtv - helper to turn string into WIRE_TX_ABORT.
+ *
+ * @ctx: context to allocate from
+ * @channel: specific channel to complain about, or NULL for all.
+ * @fmt: format for warning.
+ * @ap: accumulated varargs.
+ */
+u8 *towire_abortfmtv(const tal_t *ctx,
+		     const struct channel_id *channel,
+		     const char *fmt,
+		     va_list ap);
+
 /* BOLT #1:
  *
  * The channel is referred to by `channel_id`, unless `channel_id` is 0