fetch max total htlc value from listpeerchannel

The parameter max_htlc_value_in_flight_msat stablished by peers on
channel opening (BOLT02) can now be retrived from the
gossmods_from_listpeerchannels API.

Adapted the corresponding callback functions in renepay and askrene to
take into account that value as a constraint to the value we can send
through a channel.

Changelog-Add: fetch max_htlc_value_in_flight_msat from gossmods_listpeerchannels API

Signed-off-by: Lagrang3 <[email protected]>

Author: Lagrang3

common/gossmods_listpeerchannels.c

@@ -13,6 +13,7 @@ void gossmod_add_localchan(struct gossmap_localmods *mods,
 			   struct amount_msat htlcmin,
 			   struct amount_msat htlcmax,
 			   struct amount_msat spendable,
+			   struct amount_msat total_htlcmax,
 			   struct amount_msat fee_base,
 			   u32 fee_proportional,
 			   u16 cltv_delta,
@@ -52,6 +53,7 @@ gossmods_from_listpeerchannels_(const tal_t *ctx,
 					   struct amount_msat htlcmin,
 					   struct amount_msat htlcmax,
 					   struct amount_msat sr_able,
+					   struct amount_msat max_total_htlc,
 					   struct amount_msat fee_base,
 					   u32 fee_proportional,
 					   u16 cltv_delta,
@@ -72,6 +74,7 @@ gossmods_from_listpeerchannels_(const tal_t *ctx,
 		bool enabled;
 		struct node_id dst;
 		struct amount_msat capacity_msat, spendable, receivable, fee_base[NUM_SIDES], htlc_min[NUM_SIDES], htlc_max[NUM_SIDES];
+		struct amount_msat max_total_in_htlc, max_total_out_htlc;
 		u32 fee_proportional[NUM_SIDES], cltv_delta[NUM_SIDES];
 		const char *state, *err;
 
@@ -87,6 +90,8 @@ gossmods_from_listpeerchannels_(const tal_t *ctx,
 				"direction?:%,"
 				"spendable_msat?:%,"
 				"receivable_msat?:%,"
+				"our_max_htlc_value_in_flight_msat?:%,"
+				"their_max_htlc_value_in_flight_msat?:%,"
 				"peer_connected:%,"
 				"state:%,"
 				"peer_id:%,"
@@ -109,6 +114,8 @@ gossmods_from_listpeerchannels_(const tal_t *ctx,
 				JSON_SCAN(json_to_int, &scidd.dir),
 				JSON_SCAN(json_to_msat, &spendable),
 				JSON_SCAN(json_to_msat, &receivable),
+				JSON_SCAN(json_to_msat, &max_total_in_htlc),
+				JSON_SCAN(json_to_msat, &max_total_out_htlc),
 				JSON_SCAN(json_to_bool, &enabled),
 				JSON_SCAN_TAL(tmpctx, json_strdup, &state),
 				JSON_SCAN(json_to_node_id, &dst),
@@ -155,7 +162,7 @@ gossmods_from_listpeerchannels_(const tal_t *ctx,
 		/* We add both directions */
 		cb(mods, self, &dst, &scidd, capacity_msat,
 		   htlc_min[LOCAL], htlc_max[LOCAL],
-		   spendable, fee_base[LOCAL], fee_proportional[LOCAL],
+		   spendable, max_total_out_htlc, fee_base[LOCAL], fee_proportional[LOCAL],
 		   cltv_delta[LOCAL], enabled, buf, channel, cbarg);
 
 		/* If we didn't have a remote update, it's not usable yet */
@@ -166,7 +173,7 @@ gossmods_from_listpeerchannels_(const tal_t *ctx,
 
 		cb(mods, self, &dst, &scidd, capacity_msat,
 		   htlc_min[REMOTE], htlc_max[REMOTE],
-		   receivable, fee_base[REMOTE], fee_proportional[REMOTE],
+		   receivable, max_total_in_htlc, fee_base[REMOTE], fee_proportional[REMOTE],
 		   cltv_delta[REMOTE], enabled, buf, channel, cbarg);
 	}
 

common/gossmods_listpeerchannels.h

@@ -34,6 +34,7 @@ struct gossmap_localmods *gossmods_from_listpeerchannels_(const tal_t *ctx,
 								     struct amount_msat htlcmin,
 								     struct amount_msat htlcmax,
 								     struct amount_msat spendable,
+								     struct amount_msat total_htlcmax,
 								     struct amount_msat fee_base,
 								     u32 fee_proportional,
 								     u16 cltv_delta,
@@ -55,6 +56,7 @@ struct gossmap_localmods *gossmods_from_listpeerchannels_(const tal_t *ctx,
 							    struct amount_msat,	\
 							    struct amount_msat,	\
 							    struct amount_msat,	\
+							    struct amount_msat,	\
 							    u32,	\
 							    u16,	\
 							    bool,	\
@@ -71,6 +73,7 @@ void gossmod_add_localchan(struct gossmap_localmods *mods,
 			   struct amount_msat htlcmin,
 			   struct amount_msat htlcmax,
 			   struct amount_msat spendable,
+			   struct amount_msat total_htlcmax,
 			   struct amount_msat fee_base,
 			   u32 fee_proportional,
 			   u16 cltv_delta,

plugins/askrene/askrene.c

@@ -699,6 +699,7 @@ static void add_localchan(struct gossmap_localmods *mods,
 			  struct amount_msat htlcmin,
 			  struct amount_msat htlcmax,
 			  struct amount_msat spendable,
+			  struct amount_msat max_total_htlc,
 			  struct amount_msat fee_base,
 			  u32 fee_proportional,
 			  u16 cltv_delta,
@@ -759,8 +760,10 @@ static void add_localchan(struct gossmap_localmods *mods,
 		additional_cost_htable_add(info->additional_costs, phc);
 	}
 
+	/* can't send more than expendable and no more than max_total_htlc */
+	struct amount_msat max_msat = amount_msat_min(spendable, max_total_htlc);
 	/* Known capacity on local channels (ts = max) */
-	layer_add_constraint(info->local_layer, scidd, UINT64_MAX, &spendable, &spendable);
+	layer_add_constraint(info->local_layer, scidd, UINT64_MAX, &max_msat, &max_msat);
 }
 
 static struct command_result *

plugins/renepay/mods.c

@@ -343,6 +343,7 @@ static void gossmod_cb(struct gossmap_localmods *mods,
 		       struct amount_msat htlcmin,
 		       struct amount_msat htlcmax,
 		       struct amount_msat spendable,
+		       struct amount_msat max_total_htlc,
 		       struct amount_msat fee_base,
 		       u32 fee_proportional,
 		       u16 cltv_delta,
@@ -354,9 +355,10 @@ static void gossmod_cb(struct gossmap_localmods *mods,
 	struct amount_msat min, max;
 
 	if (scidd->dir == node_id_idx(self, peer)) {
-		/* local channels can send up to what's spendable */
+		/* local channels can send up to what's spendable but there is a
+		 * limit also the total amount in-flight */
 		min = AMOUNT_MSAT(0);
-		max = spendable;
+		max = amount_msat_min(spendable, max_total_htlc);
 	} else {
 		/* remote channels can send up no more than spendable */
 		min = htlcmin;

plugins/test/run-route-calc.c

@@ -54,6 +54,7 @@ void gossmod_add_localchan(struct gossmap_localmods *mods UNNEEDED,
 			   struct amount_msat htlcmin UNNEEDED,
 			   struct amount_msat htlcmax UNNEEDED,
 			   struct amount_msat spendable UNNEEDED,
+			   struct amount_msat total_htlcmax UNNEEDED,
 			   struct amount_msat fee_base UNNEEDED,
 			   u32 fee_proportional UNNEEDED,
 			   u16 cltv_delta UNNEEDED,
@@ -76,6 +77,7 @@ struct gossmap_localmods *gossmods_from_listpeerchannels_(const tal_t *ctx UNNEE
 								     struct amount_msat htlcmin UNNEEDED,
 								     struct amount_msat htlcmax UNNEEDED,
 								     struct amount_msat spendable UNNEEDED,
+								     struct amount_msat total_htlcmax UNNEEDED,
 								     struct amount_msat fee_base UNNEEDED,
 								     u32 fee_proportional UNNEEDED,
 								     u16 cltv_delta UNNEEDED,

plugins/test/run-route-overlong.c

@@ -51,6 +51,7 @@ void gossmod_add_localchan(struct gossmap_localmods *mods UNNEEDED,
 			   struct amount_msat htlcmin UNNEEDED,
 			   struct amount_msat htlcmax UNNEEDED,
 			   struct amount_msat spendable UNNEEDED,
+			   struct amount_msat total_htlcmax UNNEEDED,
 			   struct amount_msat fee_base UNNEEDED,
 			   u32 fee_proportional UNNEEDED,
 			   u16 cltv_delta UNNEEDED,
@@ -73,6 +74,7 @@ struct gossmap_localmods *gossmods_from_listpeerchannels_(const tal_t *ctx UNNEE
 								     struct amount_msat htlcmin UNNEEDED,
 								     struct amount_msat htlcmax UNNEEDED,
 								     struct amount_msat spendable UNNEEDED,
+								     struct amount_msat total_htlcmax UNNEEDED,
 								     struct amount_msat fee_base UNNEEDED,
 								     u32 fee_proportional UNNEEDED,
 								     u16 cltv_delta UNNEEDED,

plugins/topology.c

@@ -355,6 +355,7 @@ static void gossmod_add_unknown_localchan(struct gossmap_localmods *mods,
 					  struct amount_msat min,
 					  struct amount_msat max,
 					  struct amount_msat spendable,
+					  struct amount_msat max_total_htlc,
 					  struct amount_msat fee_base,
 					  u32 fee_proportional,
 					  u16 cltv_delta,
@@ -367,7 +368,7 @@ static void gossmod_add_unknown_localchan(struct gossmap_localmods *mods,
 		return;
 
 	gossmod_add_localchan(mods, self, peer, scidd, capacity_msat,
-			      min, max, spendable,
+			      min, max, spendable, max_total_htlc,
 			      fee_base, fee_proportional, cltv_delta, enabled,
 			      buf, chantok, gossmap);
 }