channeld: add extra_tlvs from update_add_htlc msg

We currently only consider known tlv types in the internal
representation of a htlc. This commit adds the remaining unknown tlv
fields to the htlc as well. This is in prepareation to forward these to
the htlc_accepted_hook.

Signed-off-by: Peter Neuroth <[email protected]>

Author: nepet

channeld/channeld.c

@@ -621,9 +621,14 @@ static void handle_peer_add_htlc(struct peer *peer, const u8 *msg)
 		peer_failed_warn(peer->pps, &peer->channel_id,
 				 "Bad peer_add_htlc %s", tal_hex(msg, msg));
 	}
+
 	add_err = channel_add_htlc(peer->channel, REMOTE, id, amount,
 				   cltv_expiry, &payment_hash,
-				   onion_routing_packet, tlvs->blinded_path, &htlc, NULL,
+				   onion_routing_packet,
+				   take(tlvs->blinded_path), &htlc, NULL,
+				   /* NOTE: It might be better to remove the
+				    * blinded_path from the extra_tlvs */
+				   tlvs->fields,
 				   /* We don't immediately fail incoming htlcs,
 				    * instead we wait and fail them after
 				    * they've been committed */
@@ -5201,13 +5206,24 @@ static void resend_commitment(struct peer *peer, struct changed_htlc *last)
 					 last[i].id);
 
 		if (h->state == SENT_ADD_COMMIT) {
-			struct tlv_update_add_htlc_tlvs *tlvs;
-			if (h->path_key) {
+			struct tlv_update_add_htlc_tlvs *tlvs = NULL;
+			if (h->extra_tlvs || h->path_key) {
 				tlvs = tlv_update_add_htlc_tlvs_new(tmpctx);
-				tlvs->blinded_path = tal_dup(tlvs, struct pubkey,
+			}
+			if (h->extra_tlvs) {
+				tlvs->fields = tal_dup_talarr(tmpctx,
+							      struct tlv_field,
+							      h->extra_tlvs);
+			}
+			if (h->path_key) {
+				/* It is fine to just set the binded_path
+				 * independent of what is in tlv->fields as the
+				 * towire logic will serialize unknown fields
+				 * and known types seperately. */
+				tlvs->blinded_path = tal_dup(tlvs,
+							     struct pubkey,
 							     h->path_key);
-			} else
-				tlvs = NULL;
+			}
 			msg = towire_update_add_htlc(NULL, &peer->channel_id,
 						     h->id, h->amount,
 						     &h->rhash,
@@ -6165,7 +6181,7 @@ static void handle_offer_htlc(struct peer *peer, const u8 *inmsg)
 	e = channel_add_htlc(peer->channel, LOCAL, peer->htlc_id,
 			     amount, cltv_expiry, &payment_hash,
 			     onion_routing_packet, take(path_key), NULL,
-			     &htlc_fee, true);
+			     &htlc_fee, NULL, true);
 	status_debug("Adding HTLC %"PRIu64" amount=%s cltv=%u gave %s",
 		     peer->htlc_id,
 		     fmt_amount_msat(tmpctx, amount),

channeld/channeld_htlc.h

@@ -5,6 +5,7 @@
 #include <common/htlc.h>
 #include <common/pseudorand.h>
 #include <wire/onion_wire.h>
+#include <wire/tlvstream.h>
 
 struct htlc {
 	/* What's the status. */
@@ -29,6 +30,9 @@ struct htlc {
 	/* Blinding (optional). */
 	struct pubkey *path_key;
 
+	/* Any extra tlvs attached to this hltc (optional). */
+	struct tlv_field *extra_tlvs;
+
 	/* Should we immediately fail this htlc? */
 	bool fail_immediate;
 };

channeld/full_channel.c

@@ -588,6 +588,7 @@ static enum channel_add_err add_htlc(struct channel *channel,
 				     struct htlc **htlcp,
 				     bool enforce_aggregate_limits,
 				     struct amount_sat *htlc_fee,
+				     struct tlv_field *extra_tlvs,
 				     bool err_immediate_failures)
 {
 	struct htlc *htlc, *old;
@@ -613,6 +614,15 @@ static enum channel_add_err add_htlc(struct channel *channel,
 	htlc->failed = NULL;
 	htlc->r = NULL;
 	htlc->routing = tal_dup_arr(htlc, u8, routing, TOTAL_PACKET_SIZE(ROUTING_INFO_SIZE), 0);
+	if (extra_tlvs && tal_count(extra_tlvs) > 0) {
+		htlc->extra_tlvs = tal_dup_talarr(htlc, struct tlv_field, extra_tlvs);
+		for (size_t i = 0; i < tal_count(extra_tlvs); i++) {
+			/* We need to attach the value to the correct parent */
+			htlc->extra_tlvs[i].value = tal_dup_talarr(htlc, u8, htlc->extra_tlvs[i].value);
+		}
+	} else {
+		htlc->extra_tlvs = NULL;
+	}
 
 	/* FIXME: Change expiry to simple u32 */
 
@@ -905,6 +915,7 @@ enum channel_add_err channel_add_htlc(struct channel *channel,
 				      const struct pubkey *path_key TAKES,
 				      struct htlc **htlcp,
 				      struct amount_sat *htlc_fee,
+				      struct tlv_field *extra_tlvs,
 				      bool err_immediate_failures)
 {
 	enum htlc_state state;
@@ -923,7 +934,7 @@ enum channel_add_err channel_add_htlc(struct channel *channel,
 
 	return add_htlc(channel, state, id, amount, cltv_expiry,
 			payment_hash, routing, path_key,
-			htlcp, true, htlc_fee, err_immediate_failures);
+			htlcp, true, htlc_fee, extra_tlvs, err_immediate_failures);
 }
 
 struct htlc *channel_get_htlc(struct channel *channel, enum side sender, u64 id)
@@ -1621,7 +1632,7 @@ bool channel_force_htlcs(struct channel *channel,
 			     &htlcs[i]->payment_hash,
 			     htlcs[i]->onion_routing_packet,
 			     htlcs[i]->path_key,
-			     &htlc, false, NULL, false);
+			     &htlc, false, NULL, NULL, false);
 		if (e != CHANNEL_ERR_ADD_OK) {
 			status_broken("%s HTLC %"PRIu64" failed error %u",
 				     htlc_state_owner(htlcs[i]->state) == LOCAL

channeld/full_channel.h

@@ -68,7 +68,6 @@ struct channel *new_full_channel(const tal_t *ctx,
  * @remote_splice_amnt: how much is being spliced in (or out, if -ve) of remote side.
  * @other_anchor_outnum: which output (-1 if none) is the !!side anchor
  * @funding_pubkeys: The funding pubkeys (specify NULL to use channel's value).
- *
  * Returns the unsigned commitment transaction for the committed state
  * for @side, followed by the htlc transactions in output order and
  * fills in @htlc_map, or NULL on key derivation failure.
@@ -115,6 +114,7 @@ u32 actual_feerate(const struct channel *channel,
  * @routing: routing information (copied)
  * @blinding: optional blinding information for this HTLC.
  * @htlcp: optional pointer for resulting htlc: filled in if and only if CHANNEL_ERR_NONE.
+ * @extra_tlvs: optinal tlvs attached to this HTLC.
  * @err_immediate_failures: in some cases (dusty htlcs) we want to immediately
  *                          fail the htlc; for peer incoming don't want to
  *                          error, but rather mark it as failed and fail after
@@ -134,6 +134,7 @@ enum channel_add_err channel_add_htlc(struct channel *channel,
 				      const struct pubkey *blinding TAKES,
 				      struct htlc **htlcp,
 				      struct amount_sat *htlc_fee,
+				      struct tlv_field *extra_tlvs,
 				      bool err_immediate_failures);
 
 /**

channeld/test/run-full_channel.c

@@ -177,7 +177,7 @@ static const struct htlc **include_htlcs(struct channel *channel, enum side side
 		memset(&preimage, i, sizeof(preimage));
 		sha256(&hash, &preimage, sizeof(preimage));
 		e = channel_add_htlc(channel, sender, i, msatoshi, 500+i, &hash,
-				     dummy_routing, NULL, NULL, NULL, true);
+				     dummy_routing, NULL, NULL, NULL, NULL, true);
 		assert(e == CHANNEL_ERR_ADD_OK);
 		htlcs[i] = channel_get_htlc(channel, sender, i);
 	}
@@ -269,7 +269,7 @@ static void send_and_fulfill_htlc(struct channel *channel,
 	sha256(&rhash, &r, sizeof(r));
 
 	assert(channel_add_htlc(channel, sender, 1337, msatoshi, 900, &rhash,
-				dummy_routing, NULL, NULL, NULL, true)
+				dummy_routing, NULL, NULL, NULL, NULL, true)
 	       == CHANNEL_ERR_ADD_OK);
 	htlc = channel_get_htlc(channel, sender, 1337);
 	assert(htlc);

tests/plugins/channeld_fakenet.c

@@ -893,7 +893,7 @@ static void handle_offer_htlc(struct info *info, const u8 *inmsg)
 	e = channel_add_htlc(info->channel, LOCAL, htlc->htlc_id,
 			     amount, cltv_expiry, &htlc->payment_hash,
 			     onion_routing_packet, take(blinding), NULL,
-			     &htlc_fee, true);
+			     &htlc_fee, NULL, true);
 	status_debug("Adding HTLC %"PRIu64" amount=%s cltv=%u gave %s",
 		     htlc->htlc_id, fmt_amount_msat(tmpctx, amount),
 		     cltv_expiry,