gossipd: also delay locally-generated disables when peer vanishes.

Note that we mark both directions of the channel disabled immediately,
it's just the broadcast of the update which is delayed, just like the
ones generated when channeld tells us to.

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

gossipd/gossip.c

@@ -1791,6 +1791,21 @@ static void destroy_local_update(struct local_update *local_update)
 		      &local_update->list);
 }
 
+static void queue_local_update(struct daemon *daemon,
+			       struct local_update *local_update)
+{
+	/* Free any old unapplied update. */
+	tal_free(find_local_update(daemon, &local_update->scid));
+
+	list_add_tail(&daemon->local_updates, &local_update->list);
+	tal_add_destructor(local_update, destroy_local_update);
+
+	/* Delay 1/4 a broadcast interval */
+	new_reltimer(&daemon->timers, local_update,
+		     time_from_msec(daemon->broadcast_interval/4),
+		     apply_delayed_local_update, local_update);
+}
+
 static void handle_local_channel_update(struct peer *peer, const u8 *msg)
 {
 	struct chan *chan;
@@ -1838,16 +1853,7 @@ static void handle_local_channel_update(struct peer *peer, const u8 *msg)
 		return;
 	}
 
-	/* Free any old unapplied update. */
+	queue_local_update(peer->daemon, local_update);
-	tal_free(find_local_update(peer->daemon, &local_update->scid));
-
-	list_add_tail(&peer->daemon->local_updates, &local_update->list);
-	tal_add_destructor(local_update, destroy_local_update);
-
-	/* Delay 1/4 a broadcast interval */
-	new_reltimer(&peer->daemon->timers, local_update,
-		     time_from_msec(peer->daemon->broadcast_interval/4),
-		     apply_delayed_local_update, local_update);
 }
 
 /**
@@ -2868,18 +2874,17 @@ static struct wireaddr_internal *setup_listeners(const tal_t *ctx,
 	return binding;
 }
 
-static void gossip_disable_outgoing_halfchan(struct routing_state *rstate,
+static void gossip_disable_outgoing_halfchan(struct daemon *daemon,
 					     struct chan *chan)
 {
-	struct short_channel_id scid;
 	u8 direction;
 	struct half_chan *hc;
-	u16 flags, cltv_expiry_delta;
+	u16 flags;
-	u32 timestamp, fee_base_msat, fee_proportional_millionths;
+	u32 timestamp;
 	struct bitcoin_blkid chain_hash;
 	secp256k1_ecdsa_signature sig;
-	u64 htlc_minimum_msat;
+	struct local_update *local_update;
-	u8 *err, *msg;
+	struct routing_state *rstate = daemon->rstate;
 
 	direction = pubkey_eq(&chan->nodes[0]->id, &rstate->local_id)?0:1;
 	assert(chan);
@@ -2892,48 +2897,29 @@ static void gossip_disable_outgoing_halfchan(struct routing_state *rstate,
 		     type_to_string(tmpctx, struct short_channel_id, &chan->scid),
 		     direction, is_halfchan_enabled(hc), 0);
 
+	local_update = tal(daemon, struct local_update);
+	local_update->daemon = daemon;
+	local_update->direction = direction;
+
 	if (!fromwire_channel_update(
-		hc->channel_update, &sig, &chain_hash, &scid, &timestamp,
+		hc->channel_update, &sig, &chain_hash,
-		&flags, &cltv_expiry_delta, &htlc_minimum_msat, &fee_base_msat,
+		&local_update->scid, &timestamp, &flags,
-		&fee_proportional_millionths)) {
+		&local_update->cltv_delta,
+		&local_update->htlc_minimum_msat,
+		&local_update->fee_base_msat,
+		&local_update->fee_proportional_millionths)) {
 		status_failed(
 		    STATUS_FAIL_INTERNAL_ERROR,
 		    "Unable to parse previously accepted channel_update");
 	}
 
-	/* Avoid sending gratuitous disable messages, e.g., on close and
-	 * subsequent disconnect */
-	if (flags & ROUTING_FLAGS_DISABLED)
-		return;
-
 	timestamp = time_now().ts.tv_sec;
 	if (timestamp <= hc->last_timestamp)
 		timestamp = hc->last_timestamp + 1;
 
-	flags = flags | ROUTING_FLAGS_DISABLED;
+	local_update->disable = true;
-
-	msg = towire_channel_update(tmpctx, &sig, &chain_hash, &scid, timestamp,
-				    flags, cltv_expiry_delta, htlc_minimum_msat,
-				    fee_base_msat, fee_proportional_millionths);
-
-	if (!wire_sync_write(HSM_FD,
-			     towire_hsm_cupdate_sig_req(tmpctx, msg))) {
-		status_failed(STATUS_FAIL_HSM_IO, "Writing cupdate_sig_req: %s",
-			      strerror(errno));
-	}
-
-	msg = wire_sync_read(tmpctx, HSM_FD);
-	if (!msg || !fromwire_hsm_cupdate_sig_reply(tmpctx, msg, &msg)) {
-		status_failed(STATUS_FAIL_HSM_IO,
-			      "Reading cupdate_sig_req: %s",
-			      strerror(errno));
-	}
 
-	err = handle_channel_update(rstate, msg, "disable_channel");
+	queue_local_update(daemon, local_update);
-	if (err)
-		status_failed(STATUS_FAIL_INTERNAL_ERROR,
-			      "rejected disabling channel_update: %s",
-			      tal_hex(tmpctx, err));
 }
 
 /**
@@ -2948,15 +2934,17 @@ static void gossip_disable_outgoing_halfchan(struct routing_state *rstate,
  * It is important to disable the incoming edge as well since we might otherwise
  * return that edge as a `contact_point` as part of an invoice.
  */
-static void gossip_disable_local_channel(struct routing_state *rstate,
+static void gossip_disable_local_channel(struct daemon *daemon,
 					 struct chan *chan)
 {
+	struct routing_state *rstate = daemon->rstate;
+
 	assert(pubkey_eq(&rstate->local_id, &chan->nodes[0]->id) ||
 	       pubkey_eq(&rstate->local_id, &chan->nodes[1]->id));
 
 	chan->half[0].flags |= ROUTING_FLAGS_DISABLED;
 	chan->half[1].flags |= ROUTING_FLAGS_DISABLED;
-	gossip_disable_outgoing_halfchan(rstate, chan);
+	gossip_disable_outgoing_halfchan(daemon, chan);
 }
 
 static void gossip_disable_local_channels(struct daemon *daemon)
@@ -2971,7 +2959,7 @@ static void gossip_disable_local_channels(struct daemon *daemon)
 		return;
 
 	for (i = 0; i < tal_count(local_node->chans); i++)
-		gossip_disable_local_channel(daemon->rstate,
+		gossip_disable_local_channel(daemon,
 					     local_node->chans[i]);
 }
 
@@ -3511,14 +3499,15 @@ static struct io_plan *peer_important(struct io_conn *conn,
 	return daemon_conn_read_next(conn, &daemon->master);
 }
 
-static void peer_disable_channels(struct routing_state *rstate, struct node *node)
+static void peer_disable_channels(struct daemon *daemon, struct node *node)
 {
 	struct chan *c;
 	size_t i;
 	for (i=0; i<tal_count(node->chans); i++) {
 		c = node->chans[i];
-		if (pubkey_eq(&other_node(node, c)->id, &rstate->local_id))
+		if (pubkey_eq(&other_node(node, c)->id,
-			gossip_disable_local_channel(rstate, c);
+			      &daemon->rstate->local_id))
+			gossip_disable_local_channel(daemon, c);
 	}
 }
 
@@ -3546,7 +3535,7 @@ static struct io_plan *peer_disconnected(struct io_conn *conn,
 	/* Disable any channels to and from this peer */
 	node = get_node(daemon->rstate, &id);
 	if (node)
-		peer_disable_channels(daemon->rstate, node);
+		peer_disable_channels(daemon, node);
 
 	tal_free(peer);
 
@@ -3693,7 +3682,7 @@ static struct io_plan *handle_local_channel_close(struct io_conn *conn,
 
 	chan = get_channel(rstate, &scid);
 	if (chan)
-		gossip_disable_local_channel(rstate, chan);
+		gossip_disable_local_channel(daemon, chan);
 	return daemon_conn_read_next(conn, &daemon->master);
 }