lightningd: add `blinding` and `enctlv` field to `struct route_hop`.

This will be used when we want to specify these in a route.  But for now, they
only alter gossipd, which always sets them to NULL.

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

gossipd/gossipd.c

@@ -891,7 +891,7 @@ static struct io_plan *getroute_req(struct io_conn *conn, struct daemon *daemon,
 	u64 riskfactor_millionths;
 	u32 max_hops;
 	u8 *out;
-	struct route_hop *hops;
+	struct route_hop **hops;
 	/* fuzz 12.345% -> fuzz_millionths = 12345000 */
 	u64 fuzz_millionths;
 	struct exclude_entry **excluded;
@@ -924,7 +924,9 @@ static struct io_plan *getroute_req(struct io_conn *conn, struct daemon *daemon,
 			 fuzz_millionths / 1000000.0, pseudorand_u64(),
 			 excluded, max_hops);
 
-	out = towire_gossip_getroute_reply(NULL, hops);
+	out = towire_gossip_getroute_reply(NULL,
+					   cast_const2(const struct route_hop **,
+						       hops));
 	daemon_conn_send(daemon->master, take(out));
 	return daemon_conn_read_next(conn, daemon->master);
 }

gossipd/routing.c

@@ -2630,20 +2630,20 @@ u8 *handle_node_announcement(struct routing_state *rstate, const u8 *node_ann,
 	return NULL;
 }
 
-struct route_hop *get_route(const tal_t *ctx, struct routing_state *rstate,
-			    const struct node_id *source,
-			    const struct node_id *destination,
-			    struct amount_msat msat, double riskfactor,
-			    u32 final_cltv,
-			    double fuzz, u64 seed,
-			    struct exclude_entry **excluded,
-			    u32 max_hops)
+struct route_hop **get_route(const tal_t *ctx, struct routing_state *rstate,
+			     const struct node_id *source,
+			     const struct node_id *destination,
+			     struct amount_msat msat, double riskfactor,
+			     u32 final_cltv,
+			     double fuzz, u64 seed,
+			     struct exclude_entry **excluded,
+			     u32 max_hops)
 {
 	struct chan **route;
 	struct amount_msat total_amount;
 	unsigned int total_delay;
 	struct amount_msat fee;
-	struct route_hop *hops;
+	struct route_hop **hops;
 	struct node *n;
 	struct amount_msat *saved_capacity;
 	struct short_channel_id_dir *excluded_chan;
@@ -2717,7 +2717,7 @@ struct route_hop *get_route(const tal_t *ctx, struct routing_state *rstate,
 	}
 
 	/* Fees, delays need to be calculated backwards along route. */
-	hops = tal_arr(ctx, struct route_hop, tal_count(route));
+	hops = tal_arr(ctx, struct route_hop *, tal_count(route));
 	total_amount = msat;
 	total_delay = final_cltv;
 
@@ -2728,12 +2728,15 @@ struct route_hop *get_route(const tal_t *ctx, struct routing_state *rstate,
 
 		int idx = half_chan_to(n, route[i]);
 		c = &route[i]->half[idx];
-		hops[i].channel_id = route[i]->scid;
-		hops[i].nodeid = n->id;
-		hops[i].amount = total_amount;
-		hops[i].delay = total_delay;
-		hops[i].direction = idx;
-		hops[i].style = n->hop_style;
+		hops[i] = tal(hops, struct route_hop);
+		hops[i]->channel_id = route[i]->scid;
+		hops[i]->nodeid = n->id;
+		hops[i]->amount = total_amount;
+		hops[i]->delay = total_delay;
+		hops[i]->direction = idx;
+		hops[i]->style = n->hop_style;
+		hops[i]->blinding = NULL;
+		hops[i]->enctlv = NULL;
 
 		/* Since we calculated this route, it should not overflow! */
 		if (!amount_msat_add_fee(&total_amount,

gossipd/routing.h

@@ -325,6 +325,8 @@ struct route_hop {
 	struct node_id nodeid;
 	struct amount_msat amount;
 	u32 delay;
+	struct pubkey *blinding;
+	u8 *enctlv;
 	enum route_hop_style style;
 };
 
@@ -408,15 +410,15 @@ struct node *get_node(struct routing_state *rstate,
 		      const struct node_id *id);
 
 /* Compute a route to a destination, for a given amount and riskfactor. */
-struct route_hop *get_route(const tal_t *ctx, struct routing_state *rstate,
-			    const struct node_id *source,
-			    const struct node_id *destination,
-			    const struct amount_msat msat, double riskfactor,
-			    u32 final_cltv,
-			    double fuzz,
-			    u64 seed,
-			    struct exclude_entry **excluded,
-			    u32 max_hops);
+struct route_hop **get_route(const tal_t *ctx, struct routing_state *rstate,
+			     const struct node_id *source,
+			     const struct node_id *destination,
+			     const struct amount_msat msat, double riskfactor,
+			     u32 final_cltv,
+			     double fuzz,
+			     u64 seed,
+			     struct exclude_entry **excluded,
+			     u32 max_hops);
 /* Disable channel(s) based on the given routing failure. */
 void routing_failure(struct routing_state *rstate,
 		     const struct node_id *erring_node,

lightningd/gossip_control.c

@@ -333,12 +333,12 @@ static void json_add_route_hop(struct json_stream *r, char const *n,
 
 /* Output a route */
 static void json_add_route(struct json_stream *r, char const *n,
-			   const struct route_hop *hops, size_t hops_len)
+			   struct route_hop **hops, size_t hops_len)
 {
 	size_t i;
 	json_array_start(r, n);
 	for (i = 0; i < hops_len; ++i) {
-		json_add_route_hop(r, NULL, &hops[i]);
+		json_add_route_hop(r, NULL, hops[i]);
 	}
 	json_array_end(r);
 }
@@ -347,7 +347,7 @@ static void json_getroute_reply(struct subd *gossip UNUSED, const u8 *reply, con
 				struct command *cmd)
 {
 	struct json_stream *response;
-	struct route_hop *hops;
+	struct route_hop **hops;
 
 	fromwire_gossip_getroute_reply(reply, reply, &hops);
 

lightningd/gossip_msg.c

@@ -58,14 +58,28 @@ void towire_gossip_getnodes_entry(u8 **pptr,
 	towire(pptr, entry->color, ARRAY_SIZE(entry->color));
 }
 
-void fromwire_route_hop(const u8 **pptr, size_t *max, struct route_hop *entry)
+struct route_hop *fromwire_route_hop(const tal_t *ctx,
+				     const u8 **pptr, size_t *max)
 {
+	struct route_hop *entry = tal(ctx, struct route_hop);
+	size_t enclen;
+
 	fromwire_node_id(pptr, max, &entry->nodeid);
 	fromwire_short_channel_id(pptr, max, &entry->channel_id);
 	entry->direction = fromwire_u8(pptr, max);
 	entry->amount = fromwire_amount_msat(pptr, max);
 	entry->delay = fromwire_u32(pptr, max);
 	entry->style = fromwire_u8(pptr, max);
+	if (fromwire_bool(pptr, max)) {
+		entry->blinding = tal(entry, struct pubkey);
+		fromwire_pubkey(pptr, max, entry->blinding);
+	}
+	enclen = fromwire_u16(pptr, max);
+	if (enclen)
+		entry->enctlv = fromwire_tal_arrn(entry, pptr, max, enclen);
+	else
+		entry->enctlv = NULL;
+	return entry;
 }
 
 void towire_route_hop(u8 **pptr, const struct route_hop *entry)
@@ -76,6 +90,13 @@ void towire_route_hop(u8 **pptr, const struct route_hop *entry)
 	towire_amount_msat(pptr, entry->amount);
 	towire_u32(pptr, entry->delay);
 	towire_u8(pptr, entry->style);
+	if (entry->blinding) {
+		towire_bool(pptr, true);
+		towire_pubkey(pptr, entry->blinding);
+	} else
+		towire_bool(pptr, false);
+	towire_u16(pptr, tal_bytelen(entry->enctlv));
+	towire_u8_array(pptr, entry->enctlv, tal_bytelen(entry->enctlv));
 }
 
 void fromwire_route_info(const u8 **pptr, size_t *max, struct route_info *entry)

lightningd/gossip_msg.h

@@ -40,7 +40,8 @@ fromwire_gossip_getnodes_entry(const tal_t *ctx, const u8 **pptr, size_t *max);
 void towire_gossip_getnodes_entry(u8 **pptr,
 				  const struct gossip_getnodes_entry *entry);
 
-void fromwire_route_hop(const u8 **pprt, size_t *max, struct route_hop *entry);
+struct route_hop *fromwire_route_hop(const tal_t *ctx,
+				     const u8 **pptr, size_t *max);
 void towire_route_hop(u8 **pprt, const struct route_hop *entry);
 
 void fromwire_route_info(const u8 **pprt, size_t *max, struct route_info *entry);

tools/generate-wire.py

@@ -228,6 +228,7 @@ class Type(FieldSet):
         'witscript',
         'feature_set',
         'onionmsg_path',
+        'route_hop',
     ]
 
     # Some BOLT types are re-typed based on their field name