lightningd: handle reestablish directly from connectd.

We don't need to hand it to channeld: it will read it!  We simply
need to tell it to expect it.

Similarly, openingd/dualopend will never see it, so remove that logic.

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

channeld/channeld.c

@@ -2682,7 +2682,7 @@ static bool fromwire_channel_reestablish_notlvs(const void *p, struct channel_id
 
 static void peer_reconnect(struct peer *peer,
 			   const struct secret *last_remote_per_commit_secret,
-			   u8 *reestablish_only)
+			   bool reestablish_only)
 {
 	struct channel_id channel_id;
 	/* Note: BOLT #2 uses these names! */
@@ -2820,23 +2820,23 @@ skip_tlvs:
 
 	peer_billboard(false, "Sent reestablish, waiting for theirs");
 
-	/* If they sent reestablish, we analyze it for courtesy, but also
-	 * in case *they* are ahead of us! */
-	if (reestablish_only) {
-		msg = reestablish_only;
-		goto got_reestablish;
-	}
-
 	/* Read until they say something interesting (don't forward
 	 * gossip *to* them yet: we might try sending channel_update
 	 * before we've reestablished channel). */
 	do {
 		clean_tmpctx();
 		msg = peer_read(tmpctx, peer->pps);
+
+		/* connectd promised us the msg was reestablish? */
+		if (reestablish_only) {
+			if (fromwire_peektype(msg) != WIRE_CHANNEL_REESTABLISH)
+				status_failed(STATUS_FAIL_INTERNAL_ERROR,
+					      "Expected reestablish, got: %s",
+					      tal_hex(tmpctx, msg));
+		}
 	} while (handle_peer_error(peer->pps, &peer->channel_id, msg) ||
 		 capture_premature_msg(&premature_msgs, msg));
 
-got_reestablish:
 #if EXPERIMENTAL_FEATURES
 	recv_tlvs = tlv_channel_reestablish_tlvs_new(tmpctx);
 
@@ -3730,7 +3730,7 @@ static void init_channel(struct peer *peer)
 	secp256k1_ecdsa_signature *remote_ann_node_sig;
 	secp256k1_ecdsa_signature *remote_ann_bitcoin_sig;
 	struct penalty_base *pbases;
-	u8 *reestablish_only;
+	bool reestablish_only;
 	struct channel_type *channel_type;
 	u32 *dev_disable_commit; /* Always NULL */
 	bool dev_fast_gossip;

channeld/channeld_wire.csv

@@ -80,8 +80,7 @@ msgdata,channeld_init,dev_fail_process_onionpacket,bool,
 msgdata,channeld_init,dev_disable_commit,?u32,
 msgdata,channeld_init,num_penalty_bases,u32,
 msgdata,channeld_init,pbases,penalty_base,num_penalty_bases
-msgdata,channeld_init,reestablish_only_len,u16,
-msgdata,channeld_init,reestablish_only,u8,reestablish_only_len
+msgdata,channeld_init,reestablish_only,bool,
 msgdata,channeld_init,channel_update_len,u16,
 msgdata,channeld_init,channel_update,u8,channel_update_len
 

lightningd/channel_control.c

@@ -568,7 +568,7 @@ void peer_start_channeld(struct channel *channel,
 			 struct peer_fd *peer_fd,
 			 const u8 *fwd_msg,
 			 bool reconnected,
-			 const u8 *reestablish_only)
+			 bool reestablish_only)
 {
 	u8 *initmsg;
 	int hsmfd;

lightningd/channel_control.h

@@ -14,7 +14,7 @@ void peer_start_channeld(struct channel *channel,
 			 struct peer_fd *peer_fd,
 			 const u8 *fwd_msg,
 			 bool reconnected,
-			 const u8 *reestablish_only);
+			 bool reestablish_only);
 
 /* Returns true if subd told, otherwise false. */
 bool channel_tell_depth(struct lightningd *ld,

lightningd/opening_common.c

@@ -166,38 +166,3 @@ void channel_config(struct lightningd *ld,
 	 /* This is filled in by lightning_openingd, for consistency. */
 	 ours->channel_reserve = AMOUNT_SAT(UINT64_MAX);
 }
-
-void handle_reestablish(struct lightningd *ld,
-			const struct node_id *peer_id,
-			const struct channel_id *channel_id,
-			const u8 *reestablish,
-			struct peer_fd *peer_fd)
-{
-	struct peer *peer;
-	struct channel *c;
-
-	/* We very carefully re-xmit the last reestablish, so they can get
-	 * their secrets back.  We don't otherwise touch them. */
-	peer = peer_by_id(ld, peer_id);
-	if (peer)
-		c = find_channel_by_id(peer, channel_id);
-	else
-		c = NULL;
-
-	if (c && channel_closed(c)) {
-		log_debug(c->log, "Reestablish on %s channel: using channeld to reply",
-			  channel_state_name(c));
-		peer_start_channeld(c, peer_fd, NULL, true, reestablish);
-	} else {
-		const u8 *err = towire_errorfmt(tmpctx, channel_id,
-				      "Unknown channel for reestablish");
-		log_debug(ld->log, "Reestablish on UNKNOWN channel %s",
-			  type_to_string(tmpctx, struct channel_id, channel_id));
-		/* Unless we're shutting down */
-		if (ld->connectd)
-			subd_send_msg(ld->connectd,
-				      take(towire_connectd_peer_final_msg(NULL, peer_id,
-									  err)));
-		tal_free(peer_fd);
-	}
-}

lightningd/opening_common.h

@@ -123,10 +123,4 @@ void channel_config(struct lightningd *ld,
 		    u32 *max_to_self_delay,
 		    struct amount_msat *min_effective_htlc_capacity);
 
-void handle_reestablish(struct lightningd *ld,
-			const struct node_id *peer_id,
-			const struct channel_id *channel_id,
-			const u8 *reestablish,
-			struct peer_fd *peer_fd);
-
 #endif /* LIGHTNING_LIGHTNINGD_OPENING_COMMON_H */

lightningd/opening_control.c

@@ -804,32 +804,6 @@ static void opening_got_offer(struct subd *openingd,
 	plugin_hook_call_openchannel(openingd->ld, payload);
 }
 
-static void opening_got_reestablish(struct subd *openingd, const u8 *msg,
-				    const int fds[2],
-				    struct uncommitted_channel *uc)
-{
-	struct lightningd *ld = openingd->ld;
-	struct node_id peer_id = uc->peer->id;
-	struct channel_id channel_id;
-	u8 *reestablish;
-	struct peer_fd *peer_fd;
-
-	peer_fd = new_peer_fd_arr(tmpctx, fds);
-
-	if (!fromwire_openingd_got_reestablish(tmpctx, msg, &channel_id,
-					       &reestablish)) {
-		log_broken(openingd->log, "Malformed opening_got_reestablish %s",
-			   tal_hex(tmpctx, msg));
-		tal_free(openingd);
-		return;
-	}
-
-	/* This could free peer */
-	tal_free(uc);
-
-	handle_reestablish(ld, &peer_id, &channel_id, reestablish, peer_fd);
-}
-
 static unsigned int openingd_msg(struct subd *openingd,
 				 const u8 *msg, const int *fds)
 {
@@ -871,12 +845,6 @@ static unsigned int openingd_msg(struct subd *openingd,
 		opening_got_offer(openingd, msg, uc);
 		return 0;
 
-	case WIRE_OPENINGD_GOT_REESTABLISH:
-		if (tal_count(fds) != 1)
-			return 1;
-		opening_got_reestablish(openingd, msg, fds, uc);
-		return 0;
-
 	/* We send these! */
 	case WIRE_OPENINGD_INIT:
 	case WIRE_OPENINGD_FUNDER_START:

lightningd/peer_control.c

@@ -1337,18 +1337,48 @@ void peer_active(struct lightningd *ld, const u8 *msg, int fd)
 							  &peer->id));
 			}
 		}
-	} else {
-		/* OK, it's unsolicited.  What kind of open do they want? */
-		if (dual_fund) {
-			channel = new_unsaved_channel(peer,
-						      peer->ld->config.fee_base,
-						      peer->ld->config.fee_per_satoshi);
-			peer_start_dualopend(peer, peer_fd, channel);
+		return;
+	}
+
+	/* It's possible that they want to reestablish a channel, but
+	 * it's closed? */
+	if (*msgtype == WIRE_CHANNEL_REESTABLISH && channel_id) {
+		channel = find_channel_by_id(peer, channel_id);
+		if (channel && channel_closed(channel)) {
+			log_debug(channel->log,
+				  "Reestablish on %s channel: using channeld to reply",
+				  channel_state_name(channel));
+			peer_start_channeld(channel, peer_fd, NULL, true, true);
+			return;
 		} else {
-			peer->uncommitted_channel = new_uncommitted_channel(peer);
-			peer_start_openingd(peer, peer_fd);
+			const u8 *err = towire_errorfmt(tmpctx, channel_id,
+						"Unknown channel for reestablish");
+			log_peer_debug(ld->log, &peer->id,
+				       "Reestablish on UNKNOWN channel %s",
+				       type_to_string(tmpctx, struct channel_id,
+						      channel_id));
+			/* Unless we're shutting down, tell connectd to send err */
+			if (ld->connectd)
+				subd_send_msg(ld->connectd,
+				      take(towire_connectd_peer_final_msg(NULL,
+									  &peer->id,
+									  err)));
+			else
+				peer->is_connected = false;
+			return;
 		}
 	}
+
+	/* OK, it's unsolicited.  What kind of open do they want? */
+	if (dual_fund) {
+		channel = new_unsaved_channel(peer,
+					      peer->ld->config.fee_base,
+					      peer->ld->config.fee_per_satoshi);
+		peer_start_dualopend(peer, peer_fd, channel);
+	} else {
+		peer->uncommitted_channel = new_uncommitted_channel(peer);
+		peer_start_openingd(peer, peer_fd);
+	}
 	return;
 
 send_error:

lightningd/test/run-invoice-select-inchan.c

@@ -187,6 +187,10 @@ bool feature_negotiated(const struct feature_set *our_features UNNEEDED,
 /* Generated stub for featurebits_or */
 u8 *featurebits_or(const tal_t *ctx UNNEEDED, const u8 *f1 TAKES UNNEEDED, const u8 *f2 TAKES UNNEEDED)
 { fprintf(stderr, "featurebits_or called!\n"); abort(); }
+/* Generated stub for find_channel_by_id */
+struct channel *find_channel_by_id(const struct peer *peer UNNEEDED,
+				   const struct channel_id *cid UNNEEDED)
+{ fprintf(stderr, "find_channel_by_id called!\n"); abort(); }
 /* Generated stub for find_plugin_for_command */
 struct plugin *find_plugin_for_command(struct lightningd *ld UNNEEDED,
 				       const char *cmd_name UNNEEDED)
@@ -594,7 +598,7 @@ void peer_start_channeld(struct channel *channel UNNEEDED,
 			 struct peer_fd *peer_fd UNNEEDED,
 			 const u8 *fwd_msg UNNEEDED,
 			 bool reconnected UNNEEDED,
-			 const u8 *reestablish_only UNNEEDED)
+			 bool reestablish_only UNNEEDED)
 { fprintf(stderr, "peer_start_channeld called!\n"); abort(); }
 /* Generated stub for peer_start_dualopend */
 bool peer_start_dualopend(struct peer *peer UNNEEDED, struct peer_fd *peer_fd UNNEEDED,

openingd/openingd.c

@@ -1251,11 +1251,6 @@ static u8 *handle_peer_in(struct state *state)
 
 	extracted = extract_channel_id(msg, &channel_id);
 
-	/* Reestablish on some now-closed channel?  Be nice. */
-	if (extracted && fromwire_peektype(msg) == WIRE_CHANNEL_REESTABLISH) {
-		return towire_openingd_got_reestablish(NULL,
-						       &channel_id, msg);
-	}
 	peer_write(state->pps,
 			  take(towire_warningfmt(NULL,
 						 extracted ? &channel_id : NULL,
@@ -1352,7 +1347,6 @@ static u8 *handle_master_in(struct state *state)
 	case WIRE_OPENINGD_FAILED:
 	case WIRE_OPENINGD_GOT_OFFER:
 	case WIRE_OPENINGD_GOT_OFFER_REPLY:
-	case WIRE_OPENINGD_GOT_REESTABLISH:
 		break;
 	}
 

openingd/openingd_wire.csv

@@ -25,12 +25,6 @@ msgdata,openingd_init,min_feerate,u32,
 msgdata,openingd_init,max_feerate,u32,
 msgdata,openingd_init,dev_temporary_channel_id,?byte,32
 
-# Openingd->master: they tried to reestablish a channel.
-msgtype,openingd_got_reestablish,6001
-msgdata,openingd_got_reestablish,channel_id,channel_id,
-msgdata,openingd_got_reestablish,len,u16,
-msgdata,openingd_got_reestablish,msg,u8,len
-
 # Openingd->master: they offered channel, should we continue?
 msgtype,openingd_got_offer,6005
 msgdata,openingd_got_offer,funding_satoshis,amount_sat,

wallet/test/run-wallet.c

@@ -133,6 +133,10 @@ char *encode_scriptpubkey_to_addr(const tal_t *ctx UNNEEDED,
 /* Generated stub for fatal */
 void   fatal(const char *fmt UNNEEDED, ...)
 { fprintf(stderr, "fatal called!\n"); abort(); }
+/* Generated stub for find_channel_by_id */
+struct channel *find_channel_by_id(const struct peer *peer UNNEEDED,
+				   const struct channel_id *cid UNNEEDED)
+{ fprintf(stderr, "find_channel_by_id called!\n"); abort(); }
 /* Generated stub for fromwire_channeld_dev_memleak_reply */
 bool fromwire_channeld_dev_memleak_reply(const void *p UNNEEDED, bool *leak UNNEEDED)
 { fprintf(stderr, "fromwire_channeld_dev_memleak_reply called!\n"); abort(); }
@@ -634,7 +638,7 @@ void peer_start_channeld(struct channel *channel UNNEEDED,
 			 struct peer_fd *peer_fd UNNEEDED,
 			 const u8 *fwd_msg UNNEEDED,
 			 bool reconnected UNNEEDED,
-			 const u8 *reestablish_only UNNEEDED)
+			 bool reestablish_only UNNEEDED)
 { fprintf(stderr, "peer_start_channeld called!\n"); abort(); }
 /* Generated stub for peer_start_dualopend */
 bool peer_start_dualopend(struct peer *peer UNNEEDED, struct peer_fd *peer_fd UNNEEDED,