psbt: move channels.last_tx field to be a psbt

note: missing migration at the moment lol

bitcoin/tx.c

@@ -494,6 +494,38 @@ char *bitcoin_tx_to_psbt_base64(const tal_t *ctx, struct bitcoin_tx *tx)
 	return ret_val;
 }
 
+struct bitcoin_tx *bitcoin_tx_with_psbt(const tal_t *ctx, struct wally_psbt *psbt STEALS)
+{
+	struct wally_psbt *tmppsbt;
+	struct bitcoin_tx *tx = bitcoin_tx(ctx, chainparams,
+					   psbt->tx->num_inputs,
+					   psbt->tx->num_outputs,
+					   psbt->tx->locktime);
+	wally_tx_free(tx->wtx);
+
+	/* We want the 'finalized' tx since that includes any signature
+	 * data, not the global tx. But 'finalizing' a tx destroys some fields
+	 * so we 'clone' it first and then finalize it */
+	if (wally_psbt_clone(psbt, &tmppsbt) != WALLY_OK)
+		abort();
+
+	if (wally_finalize_psbt(tmppsbt) != WALLY_OK)
+		abort();
+
+	if (psbt_is_finalized(tmppsbt)) {
+		if (wally_extract_psbt(tmppsbt, &tx->wtx) != WALLY_OK)
+			abort();
+	} else if (wally_tx_clone(psbt->tx, &tx->wtx) != WALLY_OK)
+		abort();
+
+
+	wally_psbt_free(tmppsbt);
+
+	tal_free(tx->psbt);
+	tx->psbt = tal_steal(tx, psbt);
+	return tx;
+}
+
 struct bitcoin_tx *pull_bitcoin_tx(const tal_t *ctx, const u8 **cursor,
 				   size_t *max)
 {

bitcoin/tx.h

@@ -65,6 +65,9 @@ bool bitcoin_txid_from_hex(const char *hexstr, size_t hexstr_len,
 bool bitcoin_txid_to_hex(const struct bitcoin_txid *txid,
 			 char *hexstr, size_t hexstr_len);
 
+/* Create a bitcoin_tx from a psbt */
+struct bitcoin_tx *bitcoin_tx_with_psbt(const tal_t *ctx, struct wally_psbt *psbt);
+
 /* Internal de-linearization functions. */
 struct bitcoin_tx *pull_bitcoin_tx(const tal_t *ctx,
 				   const u8 **cursor, size_t *max);

wallet/db.c

@@ -1,5 +1,6 @@
 #include "db.h"
 
+#include <bitcoin/psbt.h>
 #include <ccan/array_size/array_size.h>
 #include <ccan/tal/str/str.h>
 #include <common/node_id.h>
@@ -1253,6 +1254,14 @@ void db_bind_tx(struct db_stmt *stmt, int col, const struct bitcoin_tx *tx)
 	db_bind_blob(stmt, col, ser, tal_count(ser));
 }
 
+void db_bind_psbt(struct db_stmt *stmt, int col, const struct wally_psbt *psbt)
+{
+	size_t bytes_written;
+	const u8 *ser = psbt_get_bytes(stmt, psbt, &bytes_written);
+	assert(ser);
+	db_bind_blob(stmt, col, ser, bytes_written);
+}
+
 void db_bind_amount_msat(struct db_stmt *stmt, int pos,
 			 const struct amount_msat *msat)
 {
@@ -1372,6 +1381,17 @@ struct bitcoin_tx *db_column_tx(const tal_t *ctx, struct db_stmt *stmt, int col)
 	return pull_bitcoin_tx(ctx, &src, &len);
 }
 
+struct bitcoin_tx *db_column_psbt_to_tx(const tal_t *ctx, struct db_stmt *stmt, int col)
+{
+	struct wally_psbt *psbt;
+	const u8 *src = db_column_blob(stmt, col);
+	size_t len = db_column_bytes(stmt, col);
+	psbt = psbt_from_bytes(ctx, src, len);
+	if (!psbt)
+		return NULL;
+	return bitcoin_tx_with_psbt(ctx, psbt);
+}
+
 void *db_column_arr_(const tal_t *ctx, struct db_stmt *stmt, int col,
 			  size_t bytes, const char *label, const char *caller)
 {

wallet/db.h

@@ -21,6 +21,7 @@ struct node_id;
 struct onionreply;
 struct db_stmt;
 struct db;
+struct wally_psbt;
 
 /**
  * Macro to annotate a named SQL query.
@@ -115,6 +116,7 @@ void db_bind_signature(struct db_stmt *stmt, int col,
 		       const secp256k1_ecdsa_signature *sig);
 void db_bind_timeabs(struct db_stmt *stmt, int col, struct timeabs t);
 void db_bind_tx(struct db_stmt *stmt, int col, const struct bitcoin_tx *tx);
+void db_bind_psbt(struct db_stmt *stmt, int col, const struct wally_psbt *psbt);
 void db_bind_amount_msat(struct db_stmt *stmt, int pos,
 			 const struct amount_msat *msat);
 void db_bind_amount_sat(struct db_stmt *stmt, int pos,
@@ -153,6 +155,7 @@ bool db_column_signature(struct db_stmt *stmt, int col,
 			 secp256k1_ecdsa_signature *sig);
 struct timeabs db_column_timeabs(struct db_stmt *stmt, int col);
 struct bitcoin_tx *db_column_tx(const tal_t *ctx, struct db_stmt *stmt, int col);
+struct bitcoin_tx *db_column_psbt_to_tx(const tal_t *ctx, struct db_stmt *stmt, int col);
 
 struct onionreply *db_column_onionreply(const tal_t *ctx,
 					struct db_stmt *stmt, int col);

wallet/wallet.c

@@ -1055,7 +1055,7 @@ static struct channel *wallet_stmt2channel(struct wallet *w, struct db_stmt *stm
 			   our_msat,
 			   msat_to_us_min, /* msatoshi_to_us_min */
 			   msat_to_us_max, /* msatoshi_to_us_max */
-			   db_column_tx(tmpctx, stmt, 33),
+			   db_column_psbt_to_tx(tmpctx, stmt, 33),
 			   &last_sig,
 			   wallet_htlc_sigs_load(tmpctx, w,
 						 db_column_u64(stmt, 0)),
@@ -1077,19 +1077,6 @@ static struct channel *wallet_stmt2channel(struct wallet *w, struct db_stmt *stm
 			   db_column_arr(tmpctx, stmt, 45, u8),
 			   db_column_int(stmt, 46));
 
-	/* as a final step, we go ahead and populate the utxo
-	 * for the last_tx with the funding amount */
-	/* FIXME: input index for funding will not always be zero! */
-	if (chan->last_tx) {
-		const u8 * funding_wscript =
-			bitcoin_redeem_2of2(tmpctx,
-					    &chan->local_funding_pubkey,
-					    &chan->channel_info.remote_fundingkey);
-		psbt_input_set_prev_utxo_wscript(chan->last_tx->psbt,
-						 0, funding_wscript,
-						 chan->funding);
-	}
-
 	return chan;
 }
 
@@ -1461,7 +1448,7 @@ void wallet_channel_save(struct wallet *w, struct channel *chan)
 
 	db_bind_u64(stmt, 17, chan->final_key_idx);
 	db_bind_u64(stmt, 18, chan->our_config.id);
-	db_bind_tx(stmt, 19, chan->last_tx);
+	db_bind_psbt(stmt, 19, chan->last_tx->psbt);
 	db_bind_signature(stmt, 20, &chan->last_sig.s);
 	db_bind_int(stmt, 21, chan->last_was_revoke);
 	db_bind_int(stmt, 22, chan->min_possible_feerate);