channeld: get handed existing HTLCs in init message.

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

lightningd/channel/channel.c

@@ -1222,6 +1222,10 @@ static void init_channel(struct peer *peer)
 	struct sha256_double funding_txid;
 	bool am_funder, last_was_revoke;
 	enum htlc_state *hstates;
+	struct fulfilled_htlc *fulfilled;
+	enum side *fulfilled_sides;
+	struct failed_htlc *failed;
+	enum side *failed_sides;
 	struct changed_htlc *last_sent_commit;
 	struct added_htlc *htlcs;
 	u8 *funding_signed;
@@ -1256,6 +1260,10 @@ static void init_channel(struct peer *peer)
 				   &peer->htlc_id,
 				   &htlcs,
 				   &hstates,
+				   &fulfilled,
+				   &fulfilled_sides,
+				   &failed,
+				   &failed_sides,
 				   &funding_signed))
 		status_failed(WIRE_CHANNEL_BAD_COMMAND, "Init: %s",
 			      tal_hex(msg, msg));
@@ -1290,6 +1298,12 @@ static void init_channel(struct peer *peer)
 				    &funding_pubkey[REMOTE],
 				    am_funder ? LOCAL : REMOTE);
 
+	if (!channel_force_htlcs(peer->channel, htlcs, hstates,
+				 fulfilled, fulfilled_sides,
+				 failed, failed_sides))
+		status_failed(WIRE_CHANNEL_BAD_COMMAND,
+			      "Could not restore HTLCs");
+
 	peer->channel_direction = get_channel_direction(
 	    &peer->node_ids[LOCAL], &peer->node_ids[REMOTE]);
 

lightningd/channel/channel_wire.csv

@@ -50,6 +50,12 @@ channel_init,,next_htlc_id,u64
 channel_init,,num_htlcs,u16
 channel_init,,htlcs,num_htlcs*struct added_htlc
 channel_init,,htlc_states,num_htlcs*enum htlc_state
+channel_init,,num_fulfilled,u16
+channel_init,,fulfilled,num_fulfilled*struct fulfilled_htlc
+channel_init,,fulfilled_sides,num_fulfilled*enum side
+channel_init,,num_failed,u16
+channel_init,,failed,num_failed*struct failed_htlc
+channel_init,,failed_sides,num_failed*enum side
 channel_init,,init_peer_pkt_len,u16
 channel_init,,init_peer_pkt,init_peer_pkt_len*u8
 

lightningd/peer_control.c

@@ -924,6 +924,10 @@ static bool peer_start_channeld_hsmfd(struct subd *hsm, const u8 *resp,
 	const struct config *cfg = &peer->ld->dstate.config;
 	struct added_htlc *htlcs;
 	enum htlc_state *htlc_states;
+	struct fulfilled_htlc *fulfilled_htlcs;
+	enum side *fulfilled_sides;
+	struct failed_htlc *failed_htlcs;
+	enum side *failed_sides;
 
 	peer->owner = new_subd(peer->ld, peer->ld,
 			       "lightningd_channel", peer,
@@ -943,7 +947,8 @@ static bool peer_start_channeld_hsmfd(struct subd *hsm, const u8 *resp,
 	log_debug(peer->log, "Waiting for funding confirmations");
 	peer_set_condition(peer, GETTING_HSMFD, CHANNELD_AWAITING_LOCKIN);
 
-	peer_htlcs(resp, peer, &htlcs, &htlc_states);
+	peer_htlcs(resp, peer, &htlcs, &htlc_states, &fulfilled_htlcs,
+		   &fulfilled_sides, &failed_htlcs, &failed_sides);
 
 	initmsg = towire_channel_init(peer,
 				      peer->funding_txid,
@@ -974,6 +979,8 @@ static bool peer_start_channeld_hsmfd(struct subd *hsm, const u8 *resp,
 				      peer->num_revocations_received,
 				      peer->next_htlc_id,
 				      htlcs, htlc_states,
+				      fulfilled_htlcs, fulfilled_sides,
+				      failed_htlcs, failed_sides,
 				      peer->funding_signed);
 
 	/* Don't need this any more (we never re-transmit it) */

lightningd/peer_htlcs.c

@@ -1118,11 +1118,46 @@ static void add_htlc(struct added_htlc **htlcs,
 	*h = state;
 }
 
+static void add_fulfill(u64 id, enum side side,
+			const struct preimage *payment_preimage,
+			struct fulfilled_htlc **fulfilled_htlcs,
+			enum side **fulfilled_sides)
+{
+	struct fulfilled_htlc *f;
+	enum side *s;
+
+	f = tal_arr_append(fulfilled_htlcs);
+	s = tal_arr_append(fulfilled_sides);
+	f->id = id;
+	f->payment_preimage = *payment_preimage;
+	*s = side;
+}
+
+static void add_fail(u64 id, enum side side,
+		     const u8 *failuremsg,
+		     struct failed_htlc **failed_htlcs,
+		     enum side **failed_sides)
+{
+	struct failed_htlc *f;
+	enum side *s;
+
+	f = tal_arr_append(failed_htlcs);
+	s = tal_arr_append(failed_sides);
+	f->id = id;
+	f->failreason = tal_dup_arr(*failed_htlcs, u8,
+				    failuremsg, tal_len(failuremsg), 0);
+	*s = side;
+}
+
 /* FIXME: Load direct from db. */
 void peer_htlcs(const tal_t *ctx,
 		const struct peer *peer,
 		struct added_htlc **htlcs,
-		enum htlc_state **htlc_states)
+		enum htlc_state **htlc_states,
+		struct fulfilled_htlc **fulfilled_htlcs,
+		enum side **fulfilled_sides,
+		struct failed_htlc **failed_htlcs,
+		enum side **failed_sides)
 {
 	struct htlc_in_map_iter ini;
 	struct htlc_out_map_iter outi;
@@ -1131,6 +1166,10 @@ void peer_htlcs(const tal_t *ctx,
 
 	*htlcs = tal_arr(ctx, struct added_htlc, 0);
 	*htlc_states = tal_arr(ctx, enum htlc_state, 0);
+	*fulfilled_htlcs = tal_arr(ctx, struct fulfilled_htlc, 0);
+	*fulfilled_sides = tal_arr(ctx, enum side, 0);
+	*failed_htlcs = tal_arr(ctx, struct failed_htlc, 0);
+	*failed_sides = tal_arr(ctx, enum side, 0);
 
 	for (hin = htlc_in_map_first(&peer->ld->htlcs_in, &ini);
 	     hin;
@@ -1142,6 +1181,13 @@ void peer_htlcs(const tal_t *ctx,
 			 hin->key.id, hin->msatoshi, &hin->payment_hash,
 			 hin->cltv_expiry, hin->onion_routing_packet,
 			 hin->hstate);
+
+		if (hin->failuremsg)
+			add_fail(hin->key.id, REMOTE, hin->failuremsg,
+				 failed_htlcs, failed_sides);
+		if (hin->preimage)
+			add_fulfill(hin->key.id, REMOTE, hin->preimage,
+				    fulfilled_htlcs, fulfilled_sides);
 	}
 
 	for (hout = htlc_out_map_first(&peer->ld->htlcs_out, &outi);
@@ -1154,5 +1200,12 @@ void peer_htlcs(const tal_t *ctx,
 			 hout->key.id, hout->msatoshi, &hout->payment_hash,
 			 hout->cltv_expiry, hout->onion_routing_packet,
 			 hout->hstate);
+
+		if (hout->failuremsg)
+			add_fail(hout->key.id, LOCAL, hout->failuremsg,
+				 failed_htlcs, failed_sides);
+		if (hout->preimage)
+			add_fulfill(hout->key.id, LOCAL, hout->preimage,
+				    fulfilled_htlcs, fulfilled_sides);
 	}
 }

lightningd/peer_htlcs.h

@@ -17,7 +17,11 @@ struct channel_info {
 void peer_htlcs(const tal_t *ctx,
 		const struct peer *peer,
 		struct added_htlc **htlcs,
-		enum htlc_state **htlc_states);
+		enum htlc_state **htlc_states,
+		struct fulfilled_htlc **fulfilled_htlcs,
+		enum side **fulfilled_sides,
+		struct failed_htlc **failed_htlcs,
+		enum side **failed_sides);
 
 bool peer_save_commitsig_received(struct peer *peer, u64 commitnum);
 bool peer_save_commitsig_sent(struct peer *peer, u64 commitnum);