feerate: keep feerates separately for each side.

When we support changing them, they can be different during the transition.

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

channeld/channel.c

@@ -2017,7 +2017,7 @@ static void init_channel(struct peer *peer)
 	bool reconnected;
 	u8 *funding_signed;
 	u8 *msg;
-	u32 feerate_per_kw;
+	u32 feerate_per_kw[NUM_SIDES];
 
 	assert(!(fcntl(MASTER_FD, F_GETFL) & O_NONBLOCK));
 
@@ -2029,7 +2029,7 @@ static void init_channel(struct peer *peer)
 				   &funding_txid, &funding_txout,
 				   &funding_satoshi,
 				   &peer->conf[LOCAL], &peer->conf[REMOTE],
-				   &feerate_per_kw,
+				   feerate_per_kw,
 				   &peer->their_commit_sig,
 				   &peer->pcs.cs,
 				   &funding_pubkey[REMOTE],

channeld/channel_wire.csv

@@ -12,7 +12,8 @@ channel_init,,funding_txout,u16
 channel_init,,funding_satoshi,u64
 channel_init,,our_config,struct channel_config
 channel_init,,their_config,struct channel_config
-channel_init,,feerate_per_kw,u32
+# FIXME: Fix generate-wire.py to allow NUM_SIDES*u32 here.
+channel_init,,feerate_per_kw,2*u32
 channel_init,,first_commit_sig,secp256k1_ecdsa_signature
 channel_init,,crypto_state,struct crypto_state
 channel_init,,remote_fundingkey,struct pubkey

channeld/full_channel.c

@@ -24,7 +24,7 @@ struct channel *new_channel(const tal_t *ctx,
 			    unsigned int funding_txout,
 			    u64 funding_satoshis,
 			    u64 local_msatoshi,
-			    u32 feerate_per_kw,
+			    const u32 feerate_per_kw[NUM_SIDES],
 			    const struct channel_config *local,
 			    const struct channel_config *remote,
 			    const struct basepoints *local_basepoints,
@@ -37,13 +37,17 @@ struct channel *new_channel(const tal_t *ctx,
 						      funding_txout,
 						      funding_satoshis,
 						      local_msatoshi,
-						      feerate_per_kw,
+						      feerate_per_kw[LOCAL],
 						      local, remote,
 						      local_basepoints,
 						      remote_basepoints,
 						      local_funding_pubkey,
 						      remote_funding_pubkey,
 						      funder);
+
+	/* Feerates can be different. */
+	channel->view[REMOTE].feerate_per_kw = feerate_per_kw[REMOTE];
+
 	if (channel) {
 		channel->htlcs = tal(channel, struct htlc_map);
 		htlc_map_init(channel->htlcs);

channeld/full_channel.h

@@ -14,7 +14,7 @@
  * @funding_satoshis: The commitment transaction amount.
  * @local_msatoshi: The amount for the local side (remainder goes to remote)
  * @feerate_per_kw: feerate per kiloweight (satoshis) for the commitment
- *   transaction and HTLCS
+ *   transaction and HTLCS for each side.
  * @local: local channel configuration
  * @remote: remote channel configuration
  * @local_basepoints: local basepoints.
@@ -30,7 +30,7 @@ struct channel *new_channel(const tal_t *ctx,
 			    unsigned int funding_txout,
 			    u64 funding_satoshis,
 			    u64 local_msatoshi,
-			    u32 feerate_per_kw,
+			    const u32 feerate_per_kw[NUM_SIDES],
 			    const struct channel_config *local,
 			    const struct channel_config *remote,
 			    const struct basepoints *local_basepoints,

channeld/test/run-full_channel.c

@@ -305,7 +305,7 @@ int main(void)
 	/* We test from both sides. */
 	struct channel *lchannel, *rchannel;
 	u64 funding_amount_satoshi;
-	u32 feerate_per_kw;
+	u32 *feerate_per_kw = tal_arr(tmpctx, u32, NUM_SIDES);
 	unsigned int funding_output_index;
 	struct keyset keyset;
 	struct pubkey local_funding_pubkey, remote_funding_pubkey;
@@ -423,7 +423,7 @@ int main(void)
 
 	to_local_msat = 7000000000;
 	to_remote_msat = 3000000000;
-	feerate_per_kw = 15000;
+	feerate_per_kw[LOCAL] = feerate_per_kw[REMOTE] = 15000;
 	lchannel = new_channel(tmpctx, &funding_txid, funding_output_index,
 			       funding_amount_satoshi, to_local_msat,
 			       feerate_per_kw,
@@ -465,7 +465,7 @@ int main(void)
 			   funding_amount_satoshi,
 			   LOCAL, remote_config->to_self_delay,
 			   &keyset,
-			   feerate_per_kw,
+			   feerate_per_kw[LOCAL],
 			   local_config->dust_limit_satoshis,
 			   to_local_msat,
 			   to_remote_msat,
@@ -492,7 +492,7 @@ int main(void)
 	 */
 	to_local_msat = 6988000000;
 	to_remote_msat = 3000000000;
-	feerate_per_kw = 0;
+	feerate_per_kw[LOCAL] = feerate_per_kw[REMOTE] = 0;
 
 	/* Now, BOLT doesn't adjust owed amounts the same way we do
 	 * here: it's as if local side paid for all the HTLCs.  We can
@@ -514,8 +514,8 @@ int main(void)
 	txs_must_be_eq(txs, txs2);
 
 	/* FIXME: Adjust properly! */
-	lchannel->view[LOCAL].feerate_per_kw = feerate_per_kw;
+	lchannel->view[LOCAL].feerate_per_kw = feerate_per_kw[LOCAL];
-	rchannel->view[REMOTE].feerate_per_kw = feerate_per_kw;
+	rchannel->view[REMOTE].feerate_per_kw = feerate_per_kw[REMOTE];
 	htlcs = include_htlcs(lchannel, LOCAL);
 	include_htlcs(rchannel, REMOTE);
 
@@ -574,16 +574,16 @@ int main(void)
 
 	/* FIXME: Compare HTLCs for these too! */
 	for (i = 0; i < ARRAY_SIZE(feerates); i++) {
-		feerate_per_kw = feerates[i];
+		feerate_per_kw[LOCAL] = feerate_per_kw[REMOTE] = feerates[i];
 
-		lchannel->view[LOCAL].feerate_per_kw = feerate_per_kw;
+		lchannel->view[LOCAL].feerate_per_kw = feerate_per_kw[LOCAL];
-		rchannel->view[REMOTE].feerate_per_kw = feerate_per_kw;
+		rchannel->view[REMOTE].feerate_per_kw = feerate_per_kw[REMOTE];
 
 		raw_tx = commit_tx(tmpctx, &funding_txid, funding_output_index,
 				   funding_amount_satoshi,
 				   LOCAL, remote_config->to_self_delay,
 				   &keyset,
-				   feerate_per_kw,
+				   feerate_per_kw[LOCAL],
 				   local_config->dust_limit_satoshis,
 				   to_local_msat,
 				   to_remote_msat,

common/initial_channel.h

@@ -133,7 +133,7 @@ static inline u16 to_self_delay(const struct channel *channel, enum side side)
  * @funding_satoshis: The commitment transaction amount.
  * @local_msatoshi: The amount for the local side (remainder goes to remote)
  * @feerate_per_kw: feerate per kiloweight (satoshis) for the commitment
- *   transaction and HTLCS
+ *   transaction and HTLCS (at this stage, same for both sides)
  * @local: local channel configuration
  * @remote: remote channel configuration
  * @local_basepoints: local basepoints.

lightningd/peer_control.c

@@ -1893,7 +1893,8 @@ static void peer_start_closingd(struct peer *peer,
 	 * calculated in [BOLT
 	 * #3](03-transactions.md#fee-calculation).
 	 */
-	feelimit = commit_tx_base_fee(peer->channel_info->feerate_per_kw, 0);
+	feelimit = commit_tx_base_fee(peer->channel_info->feerate_per_kw[LOCAL],
+				      0);
 
 	maxfee = commit_tx_base_fee(get_feerate(peer->ld->topology,
 						FEERATE_IMMEDIATE), 0);
@@ -2193,11 +2194,14 @@ static void opening_funder_finished(struct subd *opening, const u8 *resp,
 					   &fc->peer->minimum_depth,
 					   &channel_info->remote_fundingkey,
 					   &funding_txid,
-					   &channel_info->feerate_per_kw)) {
+					   &channel_info->feerate_per_kw[REMOTE])) {
 		peer_internal_error(fc->peer, "bad funder_reply: %s",
 				    tal_hex(resp, resp));
 		return;
 	}
+	/* Feerates begin identical. */
+	channel_info->feerate_per_kw[LOCAL]
+		= channel_info->feerate_per_kw[REMOTE];
 
 	/* old_remote_per_commit not valid yet, copy valid one. */
 	channel_info->old_remote_per_commit = channel_info->remote_per_commit;
@@ -2312,13 +2316,17 @@ static void opening_fundee_finished(struct subd *opening,
 					   &peer->funding_satoshi,
 					   &peer->push_msat,
 					   &peer->channel_flags,
-					   &channel_info->feerate_per_kw,
+					   &channel_info->feerate_per_kw[REMOTE],
 					   &funding_signed)) {
 		peer_internal_error(peer, "bad OPENING_FUNDEE_REPLY %s",
 				    tal_hex(reply, reply));
 		return;
 	}
 
+	/* Feerates begin identical. */
+	channel_info->feerate_per_kw[LOCAL]
+		= channel_info->feerate_per_kw[REMOTE];
+
 	/* old_remote_per_commit not valid yet, copy valid one. */
 	channel_info->old_remote_per_commit = channel_info->remote_per_commit;
 

lightningd/peer_htlcs.h

@@ -14,7 +14,8 @@ struct channel_info {
 	/* The old_remote_per_commit is for the locked-in remote commit_tx,
 	 * and the remote_per_commit is for the commit_tx we're modifying now. */
 	struct pubkey remote_per_commit, old_remote_per_commit;
-	u32 feerate_per_kw;
+	/* In transition, these can be different! */
+	u32 feerate_per_kw[NUM_SIDES];
 };
 
 /* Get all HTLCs for a peer, to send in init message. */

wallet/db.c

@@ -62,7 +62,8 @@ char *dbmigrations[] = {
     "  delayed_payment_basepoint_remote BLOB,"
     "  per_commit_remote BLOB,"
     "  old_per_commit_remote BLOB,"
-    "  feerate_per_kw INTEGER,"
+    "  local_feerate_per_kw INTEGER,"
+    "  remote_feerate_per_kw INTEGER,"
     /* END channel_info */
     "  shachain_remote_id INTEGER,"
     "  shutdown_scriptpubkey_remote BLOB,"

wallet/wallet.c

@@ -438,11 +438,12 @@ static bool wallet_stmt2channel(struct wallet *w, sqlite3_stmt *stmt,
 		ok &= sqlite3_column_pubkey(stmt, col++, &channel_info->theirbase.delayed_payment);
 		ok &= sqlite3_column_pubkey(stmt, col++, &channel_info->remote_per_commit);
 		ok &= sqlite3_column_pubkey(stmt, col++, &channel_info->old_remote_per_commit);
-		channel_info->feerate_per_kw = sqlite3_column_int(stmt, col++);
+		channel_info->feerate_per_kw[LOCAL] = sqlite3_column_int(stmt, col++);
+		channel_info->feerate_per_kw[REMOTE] = sqlite3_column_int(stmt, col++);
 		wallet_channel_config_load(w, remote_config_id, &chan->peer->channel_info->their_config);
 	} else {
 		/* No channel_info, skip positions in the result */
-		col += 8;
+		col += 9;
 	}
 
 	/* Load shachain */
@@ -483,7 +484,7 @@ static bool wallet_stmt2channel(struct wallet *w, sqlite3_stmt *stmt,
 		col += 2;
 	}
 
-	assert(col == 33);
+	assert(col == 34);
 
 	chan->peer->channel = chan;
 
@@ -502,7 +503,7 @@ const char *channel_fields =
     "fundingkey_remote, revocation_basepoint_remote, "
     "payment_basepoint_remote, htlc_basepoint_remote, "
     "delayed_payment_basepoint_remote, per_commit_remote, "
-    "old_per_commit_remote, feerate_per_kw, shachain_remote_id, "
+    "old_per_commit_remote, local_feerate_per_kw, remote_feerate_per_kw, shachain_remote_id, "
     "shutdown_scriptpubkey_remote, shutdown_keyidx_local, "
     "last_sent_commit_state, last_sent_commit_id, "
     "last_tx, last_sig";
@@ -701,7 +702,8 @@ void wallet_channel_save(struct wallet *w, struct wallet_channel *chan){
 				  "  delayed_payment_basepoint_remote=?,"
 				  "  per_commit_remote=?,"
 				  "  old_per_commit_remote=?,"
-				  "  feerate_per_kw=?,"
+				  "  local_feerate_per_kw=?,"
+				  "  remote_feerate_per_kw=?,"
 				  "  channel_config_remote=?"
 				  " WHERE id=?");
 		sqlite3_bind_pubkey(stmt, 1,  &p->channel_info->remote_fundingkey);
@@ -711,9 +713,10 @@ void wallet_channel_save(struct wallet *w, struct wallet_channel *chan){
 		sqlite3_bind_pubkey(stmt, 5,  &p->channel_info->theirbase.delayed_payment);
 		sqlite3_bind_pubkey(stmt, 6,  &p->channel_info->remote_per_commit);
 		sqlite3_bind_pubkey(stmt, 7,  &p->channel_info->old_remote_per_commit);
-		sqlite3_bind_int(stmt, 8, p->channel_info->feerate_per_kw);
+		sqlite3_bind_int(stmt, 8, p->channel_info->feerate_per_kw[LOCAL]);
-		sqlite3_bind_int64(stmt, 9, p->channel_info->their_config.id);
+		sqlite3_bind_int(stmt, 9, p->channel_info->feerate_per_kw[REMOTE]);
-		sqlite3_bind_int64(stmt, 10, chan->id);
+		sqlite3_bind_int64(stmt, 10, p->channel_info->their_config.id);
+		sqlite3_bind_int64(stmt, 11, chan->id);
 		db_exec_prepared(w->db, stmt);
 	}
 

wallet/wallet_tests.c

@@ -259,7 +259,7 @@ static bool test_channel_crud(const tal_t *ctx)
 	mempat(sig, sizeof(*sig));
 	mempat(&last_commit, sizeof(last_commit));
 	pubkey_from_der(tal_hexdata(w, "02a1633cafcc01ebfb6d78e39f687a1f0995c62fc95f51ead10a02ee0be551b5dc", 66), 33, &pk);
-	ci.feerate_per_kw = 31337;
+	ci.feerate_per_kw[LOCAL] = ci.feerate_per_kw[REMOTE] = 31337;
 	mempat(&p.id, sizeof(p.id));
 	c1.peer = &p;
 	p.id = pk;