subds: remove "ignore error" from old LND nodes.

This was put in late 2019, and @t-bast says Eclair doesn't ignore their
errors and has had no issues.

It also conflicts with https://github.com/lightning/bolts/pull/932
which suggests you *should* fail when you receive an error.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

channeld/channeld.c

@@ -2231,17 +2231,10 @@ static void peer_in(struct peer *peer, const u8 *msg)
 {
 	enum peer_wire type = fromwire_peektype(msg);
 
-	/* Only count soft errors if the channel has locked-in already;
-	 * otherwise we can't cancel a channel before it has opened.
-	 */
-	bool soft_error = peer->funding_locked[REMOTE] || peer->funding_locked[LOCAL];
-
 	if (channeld_handle_custommsg(msg))
 		return;
 
-	/* Since LND seems to send errors which aren't actually fatal events,
+	if (handle_peer_gossip_or_error(peer->pps, &peer->channel_id, msg))
-	 * we treat errors here as soft. */
-	if (handle_peer_gossip_or_error(peer->pps, &peer->channel_id, soft_error, msg))
 		return;
 
 	/* Must get funding_locked before almost anything. */
@@ -2905,8 +2898,6 @@ skip_tlvs:
 	peer_write(peer->pps, take(msg));
 
 	peer_billboard(false, "Sent reestablish, waiting for theirs");
-	bool soft_error = peer->funding_locked[REMOTE]
-		|| peer->funding_locked[LOCAL];
 
 	/* If they sent reestablish, we analyze it for courtesy, but also
 	 * in case *they* are ahead of us! */
@@ -2922,8 +2913,7 @@ skip_tlvs:
 		clean_tmpctx();
 		msg = peer_read(tmpctx, peer->pps);
 	} while (channeld_handle_custommsg(msg) ||
-		 handle_peer_gossip_or_error(peer->pps, &peer->channel_id, soft_error,
+		 handle_peer_gossip_or_error(peer->pps, &peer->channel_id, msg) ||
-					     msg) ||
 		 capture_premature_msg(&premature_msgs, msg));
 
 got_reestablish:

closingd/closingd.c

@@ -136,7 +136,7 @@ static u8 *closing_read_peer_msg(const tal_t *ctx,
 			wire_sync_write(REQ_FD, take(towire_custommsg_in(NULL, msg)));
 			continue;
 		}
-		if (!handle_peer_gossip_or_error(pps, channel_id, false, msg))
+		if (!handle_peer_gossip_or_error(pps, channel_id, msg))
 			return msg;
 	}
 }

common/read_peer_msg.c

@@ -112,7 +112,6 @@ void handle_gossip_msg(struct per_peer_state *pps, const u8 *msg TAKES)
 
 bool handle_peer_gossip_or_error(struct per_peer_state *pps,
 				 const struct channel_id *channel_id,
-				 bool soft_error,
 				 const u8 *msg TAKES)
 {
 	char *err;
@@ -150,8 +149,7 @@ bool handle_peer_gossip_or_error(struct per_peer_state *pps,
 			goto handled;
 
 		/* We hang up when a warning is received. */
-		peer_failed_received_errmsg(pps, err, channel_id,
+		peer_failed_received_errmsg(pps, err, channel_id, warning);
-					    soft_error || warning);
 
 		goto handled;
 	}

common/read_peer_msg.h

@@ -58,7 +58,6 @@ bool is_wrong_channel(const u8 *msg, const struct channel_id *expected,
  * handle_peer_gossip_or_error - simple handler for all the above cases.
  * @pps: per-peer state.
  * @channel_id: the channel id of the current channel.
- * @soft_error: tell lightningd that incoming error is non-fatal.
  * @msg: the peer message (only taken if returns true).
  *
  * This returns true if it handled the packet: a gossip packet (forwarded
@@ -67,7 +66,6 @@ bool is_wrong_channel(const u8 *msg, const struct channel_id *expected,
  */
 bool handle_peer_gossip_or_error(struct per_peer_state *pps,
 				 const struct channel_id *channel_id,
-				 bool soft_error,
 				 const u8 *msg TAKES);
 
 /**

openingd/dualopend.c

@@ -3540,8 +3540,6 @@ static void do_reconnect_dance(struct state *state)
 	peer_write(state->pps, take(msg));
 
 	peer_billboard(false, "Sent reestablish, waiting for theirs");
-	bool soft_error = state->funding_locked[REMOTE]
-		|| state->funding_locked[LOCAL];
 
 	/* Read until they say something interesting (don't forward
 	 * gossip *to* them yet: we might try sending channel_update
@@ -3552,7 +3550,7 @@ static void do_reconnect_dance(struct state *state)
 	} while (dualopend_handle_custommsg(msg)
 		 || handle_peer_gossip_or_error(state->pps,
 						&state->channel_id,
-						soft_error, msg));
+						msg));
 
 	if (!fromwire_channel_reestablish
 			(msg, &cid,
@@ -3768,7 +3766,7 @@ static u8 *handle_peer_in(struct state *state)
 
 	/* Handles standard cases, and legal unknown ones. */
 	if (handle_peer_gossip_or_error(state->pps,
-					&state->channel_id, false, msg))
+					&state->channel_id, msg))
 		return NULL;
 
 	peer_write(state->pps,

openingd/openingd.c

@@ -1272,7 +1272,7 @@ static u8 *handle_peer_in(struct state *state)
 
 	/* Handles standard cases, and legal unknown ones. */
 	if (handle_peer_gossip_or_error(state->pps,
-					&state->channel_id, false, msg))
+					&state->channel_id, msg))
 		return NULL;
 
 	extracted = extract_channel_id(msg, &channel_id);