gossip: include chain_hash in gossip messages.

As per lightning-rfc change 956e8809d9d1ee87e31b855923579b96943d5e63
"BOLT 7: add chain_hashes values to channel_update and channel_announcment"

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

daemon/lightningd.c

@@ -32,6 +32,7 @@
 static struct lightningd_state *lightningd_state(void)
 {
 	struct lightningd_state *dstate = tal(NULL, struct lightningd_state);
+	struct sha256_double unused;
 
 	dstate->log_book = new_log_book(dstate, 20*1024*1024, LOG_INFORM);
 	dstate->base_log = new_log(dstate, dstate->log_book,
@@ -45,7 +46,7 @@ static struct lightningd_state *lightningd_state(void)
 	list_head_init(&dstate->wallet);
 	list_head_init(&dstate->addresses);
 	dstate->dev_never_routefail = false;
-	dstate->rstate = new_routing_state(dstate, dstate->base_log);
+	dstate->rstate = new_routing_state(dstate, dstate->base_log, &unused);
 	dstate->reexec = NULL;
 	dstate->external_ip = NULL;
 	dstate->announce = NULL;
@@ -89,6 +90,10 @@ int main(int argc, char *argv[])
 	register_opts(dstate);
 	handle_opts(dstate, argc, argv);
 
+	/* Now we can set chain_hash properly. */ 
+	dstate->rstate->chain_hash
+		= dstate->bitcoind->chainparams->genesis_blockhash;
+
 	/* Activate crash log now we're in the right place. */
 	crashlog_activate(dstate->base_log);
 

daemon/p2p_announce.c

@@ -31,7 +31,9 @@ static void broadcast_channel_update(struct lightningd_state *dstate, struct pee
 	/* Avoid triggering memcheck */
 	memset(&signature, 0, sizeof(signature));
 
-	serialized = towire_channel_update(tmpctx, &signature, &short_channel_id,
+	serialized = towire_channel_update(tmpctx, &signature,
+					   &dstate->rstate->chain_hash,
+					   &short_channel_id,
 					   timestamp,
 					   pubkey_cmp(&dstate->id, peer->id) > 0,
 					   dstate->config.min_htlc_expiry,
@@ -41,7 +43,9 @@ static void broadcast_channel_update(struct lightningd_state *dstate, struct pee
 					   dstate->config.fee_per_satoshi);
 	privkey_sign(dstate, serialized + 66, tal_count(serialized) - 66,
 		     &signature);
-	serialized = towire_channel_update(tmpctx, &signature, &short_channel_id,
+	serialized = towire_channel_update(tmpctx, &signature,
+					   &dstate->rstate->chain_hash,
+					   &short_channel_id,
 					   timestamp,
 					   pubkey_cmp(&dstate->id, peer->id) > 0,
 					   dstate->config.min_htlc_expiry,
@@ -148,6 +152,7 @@ static void broadcast_channel_announcement(struct lightningd_state *dstate, stru
 						 &bitcoin_signature[0],
 						 &bitcoin_signature[1],
 						 NULL,
+						 &dstate->rstate->chain_hash,
 						 &short_channel_id,
 						 node_id[0],
 						 node_id[1],
@@ -160,6 +165,7 @@ static void broadcast_channel_announcement(struct lightningd_state *dstate, stru
 						 &bitcoin_signature[0],
 						 &bitcoin_signature[1],
 						 NULL,
+						 &dstate->rstate->chain_hash,
 						 &short_channel_id,
 						 node_id[0],
 						 node_id[1],

daemon/routing.c

@@ -6,6 +6,7 @@
 #include "routing.h"
 #include "wire/gen_peer_wire.h"
 #include <arpa/inet.h>
+#include <bitcoin/block.h>
 #include <ccan/array_size/array_size.h>
 #include <ccan/crypto/siphash24/siphash24.h>
 #include <ccan/endian/endian.h>
@@ -16,12 +17,15 @@
 /* 365.25 * 24 * 60 / 10 */
 #define BLOCKS_PER_YEAR 52596
 
-struct routing_state *new_routing_state(const tal_t *ctx, struct log *base_log)
+struct routing_state *new_routing_state(const tal_t *ctx,
+					struct log *base_log,
+					const struct sha256_double *chain_hash)
 {
 	struct routing_state *rstate = tal(ctx, struct routing_state);
 	rstate->base_log = base_log;
 	rstate->nodes = empty_node_map(rstate);
 	rstate->broadcasts = new_broadcast_state(rstate);
+	rstate->chain_hash = *chain_hash;
 	return rstate;
 }
 
@@ -683,6 +687,7 @@ void handle_channel_announcement(
 	struct pubkey node_id_2;
 	struct pubkey bitcoin_key_1;
 	struct pubkey bitcoin_key_2;
+	struct sha256_double chain_hash;
 	const tal_t *tmpctx = tal_tmpctx(rstate);
 	u8 *features;
 
@@ -692,6 +697,7 @@ void handle_channel_announcement(
 					   &bitcoin_signature_1,
 					   &bitcoin_signature_2,
 					   &features,
+					   &chain_hash,
 					   &short_channel_id,
 					   &node_id_1, &node_id_2,
 					   &bitcoin_key_1, &bitcoin_key_2)) {
@@ -699,6 +705,20 @@ void handle_channel_announcement(
 		return;
 	}
 
+	/* BOLT #7:
+	 *
+	 * The receiving node MUST ignore the message if the specified
+	 * `chain_hash` is unknown to the receiver.
+	 */
+	if (!structeq(&chain_hash, &rstate->chain_hash)) {
+		log_debug(rstate->base_log,
+			  "Received channel_announcement for unknown chain %s",
+			  type_to_string(tmpctx, struct sha256_double,
+					 &chain_hash));
+		tal_free(tmpctx);
+		return;
+	}
+
 	// FIXME: Check features!
 	//FIXME(cdecker) Check chain topology for the anchor TX
 
@@ -751,9 +771,11 @@ void handle_channel_update(struct routing_state *rstate, const u8 *update, size_
 	u32 fee_base_msat;
 	u32 fee_proportional_millionths;
 	const tal_t *tmpctx = tal_tmpctx(rstate);
+	struct sha256_double chain_hash;
 
 	serialized = tal_dup_arr(tmpctx, u8, update, len, 0);
-	if (!fromwire_channel_update(serialized, NULL, &signature, &short_channel_id,
+	if (!fromwire_channel_update(serialized, NULL, &signature,
+				     &chain_hash, &short_channel_id,
 				     &timestamp, &flags, &expiry,
 				     &htlc_minimum_msat, &fee_base_msat,
 				     &fee_proportional_millionths)) {
@@ -761,6 +783,19 @@ void handle_channel_update(struct routing_state *rstate, const u8 *update, size_
 		return;
 	}
 
+	/* BOLT #7:
+	 *
+	 * The receiving node MUST ignore the channel update if the specified
+	 * `chain_hash` value is unknown, meaning it isn't active on the
+	 * specified chain. */
+	if (!structeq(&chain_hash, &rstate->chain_hash)) {
+		log_debug(rstate->base_log,
+			  "Received channel_update for unknown chain %s",
+			  type_to_string(tmpctx, struct sha256_double,
+					 &chain_hash));
+		tal_free(tmpctx);
+		return;
+	}
 
 	log_debug(rstate->base_log, "Received channel_update for channel %d:%d:%d(%d)",
 		  short_channel_id.blocknum,

daemon/routing.h

@@ -86,6 +86,8 @@ struct routing_state {
 	struct log *base_log;
 
 	struct broadcast_state *broadcasts;
+
+	struct sha256_double chain_hash;
 };
 
 struct route_hop {
@@ -96,7 +98,8 @@ struct route_hop {
 };
 
 //FIXME(cdecker) The log will have to be replaced for the new subdaemon, keeping for now to keep changes small.
-struct routing_state *new_routing_state(const tal_t *ctx, struct log *base_log);
+struct routing_state *new_routing_state(const tal_t *ctx, struct log *base_log,
+					const struct sha256_double *chain_hash);
 
 struct node *new_node(struct routing_state *rstate,
 		      const struct pubkey *id);

lightningd/channel/channel.c

@@ -226,7 +226,8 @@ static void send_channel_update(struct peer *peer, bool disabled)
 	flags = peer->channel_direction | (disabled << 1);
 	/* FIXME: Add configuration option to specify `htlc_minimum_msat` */
 	cupdate = towire_channel_update(
-	    tmpctx, sig, &peer->short_channel_ids[LOCAL], timestamp, flags,
+	    tmpctx, sig, &peer->chain_hash,
+	    &peer->short_channel_ids[LOCAL], timestamp, flags,
 	    peer->cltv_delta, 1, peer->fee_base, peer->fee_per_satoshi);
 
 	msg = towire_hsm_cupdate_sig_req(tmpctx, cupdate);
@@ -267,6 +268,7 @@ static u8 *create_channel_announcement(const tal_t *ctx, struct peer *peer)
 	    &peer->announcement_bitcoin_sigs[first],
 	    &peer->announcement_bitcoin_sigs[second],
 	    features,
+	    &peer->chain_hash,
 	    &peer->short_channel_ids[LOCAL], &peer->node_ids[first],
 	    &peer->node_ids[second], &peer->channel->funding_pubkey[first],
 	    &peer->channel->funding_pubkey[second]);

lightningd/gossip/gossip.c

@@ -667,7 +667,7 @@ static struct io_plan *gossip_init(struct daemon_conn *master,
 	log_book = new_log_book(daemon, 2 * 1024 * 1024, LOG_BROKEN + 1);
 	base_log =
 	    new_log(daemon, log_book, "lightningd_gossip(%u):", (int)getpid());
-	daemon->rstate = new_routing_state(daemon, base_log);
+	daemon->rstate = new_routing_state(daemon, base_log, &chain_hash);
 	return daemon_conn_read_next(master->conn, master);
 }
 

lightningd/hsm/hsm.c

@@ -175,6 +175,7 @@ static struct io_plan *handle_channel_update_sig(struct io_conn *conn,
 	u32 timestamp, fee_base_msat, fee_proportional_mill;
 	u64 htlc_minimum_msat;
 	u16 flags, cltv_expiry_delta;
+	struct sha256_double chain_hash;
 	u8 *cu;
 
 	if (!fromwire_hsm_cupdate_sig_req(tmpctx, dc->msg_in, NULL, &cu)) {
@@ -184,7 +185,8 @@ static struct io_plan *handle_channel_update_sig(struct io_conn *conn,
 		return io_close(conn);
 	}
 
-	if (!fromwire_channel_update(cu, NULL, &sig, &scid, &timestamp, &flags,
+	if (!fromwire_channel_update(cu, NULL, &sig, &chain_hash,
+				     &scid, &timestamp, &flags,
 				     &cltv_expiry_delta, &htlc_minimum_msat,
 				     &fee_base_msat, &fee_proportional_mill)) {
 		status_trace("Failed to parse inner channel_update: %s",
@@ -202,7 +204,8 @@ static struct io_plan *handle_channel_update_sig(struct io_conn *conn,
 
 	sign_hash(&node_pkey, &hash, &sig);
 
-	cu = towire_channel_update(tmpctx, &sig, &scid, timestamp, flags,
+	cu = towire_channel_update(tmpctx, &sig, &chain_hash,
+				   &scid, timestamp, flags,
 				   cltv_expiry_delta, htlc_minimum_msat,
 				   fee_base_msat, fee_proportional_mill);
 

wire/gen_peer_wire_csv

@@ -114,11 +114,12 @@ channel_announcement,128,bitcoin_signature_1,64
 channel_announcement,192,bitcoin_signature_2,64
 channel_announcement,256,len,2
 channel_announcement,258,features,len
-channel_announcement,258+len,short_channel_id,8
-channel_announcement,266+len,node_id_1,33
-channel_announcement,299+len,node_id_2,33
-channel_announcement,332+len,bitcoin_key_1,33
-channel_announcement,365+len,bitcoin_key_2,33
+channel_announcement,258+len,chain_hash,32
+channel_announcement,290+len,short_channel_id,8
+channel_announcement,298+len,node_id_1,33
+channel_announcement,331+len,node_id_2,33
+channel_announcement,364+len,bitcoin_key_1,33
+channel_announcement,397+len,bitcoin_key_2,33
 node_announcement,257
 node_announcement,0,signature,64
 node_announcement,64,flen,2
@@ -131,10 +132,11 @@ node_announcement,138+flen,addrlen,2
 node_announcement,140+flen,addresses,addrlen
 channel_update,258
 channel_update,0,signature,64
-channel_update,64,short_channel_id,8
-channel_update,72,timestamp,4
-channel_update,76,flags,2
-channel_update,78,cltv_expiry_delta,2
-channel_update,80,htlc_minimum_msat,8
-channel_update,88,fee_base_msat,4
-channel_update,92,fee_proportional_millionths,4
+channel_update,64,chain_hash,32
+channel_update,96,short_channel_id,8
+channel_update,104,timestamp,4
+channel_update,108,flags,2
+channel_update,110,cltv_expiry_delta,2
+channel_update,112,htlc_minimum_msat,8
+channel_update,120,fee_base_msat,4
+channel_update,124,fee_proportional_millionths,4

wire/test/run-peer-wire.c

@@ -137,6 +137,7 @@ struct msg_channel_update {
 	u64 htlc_minimum_msat;
 	u32 fee_base_msat;
 	u32 fee_proportional_millionths;
+	struct sha256_double chain_hash;
 	struct short_channel_id short_channel_id;
 };
 struct msg_funding_locked {
@@ -193,6 +194,7 @@ struct msg_channel_announcement {
 	secp256k1_ecdsa_signature bitcoin_signature_1;
 	secp256k1_ecdsa_signature bitcoin_signature_2;
 	u8 *features;
+	struct sha256_double chain_hash;
 	struct short_channel_id short_channel_id;
 	struct pubkey node_id_1;
 	struct pubkey node_id_2;
@@ -225,6 +227,7 @@ static void *towire_struct_channel_announcement(const tal_t *ctx,
 					   &s->bitcoin_signature_1,
 					   &s->bitcoin_signature_2,
 					   s->features,
+					   &s->chain_hash,
 					   &s->short_channel_id,
 					   &s->node_id_1,
 					   &s->node_id_2,
@@ -241,6 +244,7 @@ static struct msg_channel_announcement *fromwire_struct_channel_announcement(con
 					  &s->bitcoin_signature_1,
 					  &s->bitcoin_signature_2,
 					  &s->features,
+					  &s->chain_hash,
 					  &s->short_channel_id,
 					  &s->node_id_1,
 					  &s->node_id_2,
@@ -373,6 +377,7 @@ static void *towire_struct_channel_update(const tal_t *ctx,
 {
 	return towire_channel_update(ctx, 
 				     &s->signature,
+				     &s->chain_hash,
 				     &s->short_channel_id,
 				     s->timestamp,
 				     s->flags,
@@ -388,6 +393,7 @@ static struct msg_channel_update *fromwire_struct_channel_update(const tal_t *ct
 
 	if (fromwire_channel_update(p, plen, 
 				    &s->signature,
+				    &s->chain_hash,
 				    &s->short_channel_id,
 				    &s->timestamp,
 				    &s->flags,
@@ -700,6 +706,7 @@ static bool channel_announcement_eq(const struct msg_channel_announcement *a,
 {
 	return eq_upto(a, b, features)
 		&& eq_var(a, b, features)
+		&& eq_field(a, b, chain_hash)
 		&& short_channel_id_eq(&a->short_channel_id, &b->short_channel_id)
 		&& eq_between(a, b, node_id_1, bitcoin_key_2);
 }