wallet: mark coinbase outputs as 'immature' until spendable

Changelog-Changed: JSON-RPC: `listfunds` now lists coinbase outputs as 'immature' until they're spendable
Changelog-Changed: JSON-RPC: UTXOs aren't spendable while immature

.msggen.json

@@ -76,6 +76,7 @@
         },
         "ListfundsOutputsStatus": {
             "confirmed": 1,
+            "immature": 3,
             "spent": 2,
             "unconfirmed": 0
         },

common/utxo.c

@@ -25,6 +25,8 @@ void towire_utxo(u8 **pptr, const struct utxo *utxo)
 		towire_bool(pptr, utxo->close_info->option_anchor_outputs);
 		towire_u32(pptr, utxo->close_info->csv);
 	}
+
+	towire_bool(pptr, utxo->is_in_coinbase);
 }
 
 struct utxo *fromwire_utxo(const tal_t *ctx, const u8 **ptr, size_t *max)
@@ -55,6 +57,8 @@ struct utxo *fromwire_utxo(const tal_t *ctx, const u8 **ptr, size_t *max)
 	} else {
 		utxo->close_info = NULL;
 	}
+
+	utxo->is_in_coinbase = fromwire_bool(ptr, max);
 	return utxo;
 }
 

common/utxo.h

@@ -53,6 +53,9 @@ struct utxo {
 
 	/* The scriptPubkey if it is known */
 	u8 *scriptPubkey;
+
+	/* Is this utxo a coinbase output */
+	bool is_in_coinbase;
 };
 
 /* We lazy-evaluate whether a utxo is really still reserved. */

doc/lightning-listfunds.7.md

@@ -27,7 +27,7 @@ On success, an object is returned, containing:
   - **output** (u32): the index within *txid*
   - **amount\_msat** (msat): the amount of the output
   - **scriptpubkey** (hex): the scriptPubkey of the output
-  - **status** (string) (one of "unconfirmed", "confirmed", "spent")
+  - **status** (string) (one of "unconfirmed", "confirmed", "spent", "immature")
   - **reserved** (boolean): whether this UTXO is currently reserved for an in-flight tx
   - **address** (string, optional): the bitcoin address of the output
   - **redeemscript** (hex, optional): the redeemscript, only if it's p2sh-wrapped
@@ -73,4 +73,4 @@ RESOURCES
 
 Main web site: <https://github.com/ElementsProject/lightning>
 
-[comment]: # ( SHA256STAMP:e5c1f54c8a5008a30648e0fe5883132759fcdabd72bd7e8a00bedc360363e85e)
+[comment]: # ( SHA256STAMP:62a8754ad2a24dfb5bb4e412a2e710748bd54ef0cffaaeb7ce352f6273742431)

doc/schemas/listfunds.schema.json

@@ -50,7 +50,8 @@
             "enum": [
               "unconfirmed",
               "confirmed",
-              "spent"
+              "spent",
+              "immature"
             ]
           },
           "reserved": {

lightningd/chaintopology.c

@@ -92,7 +92,7 @@ static void filter_block_txs(struct chain_topology *topo, struct block *b)
 		txid = b->txids[i];
 		if (txfilter_match(topo->bitcoind->ld->owned_txfilter, tx)) {
 			wallet_extract_owned_outputs(topo->bitcoind->ld->wallet,
-						     tx->wtx, &b->height, &owned);
+						     tx->wtx, i, &b->height, &owned);
 			wallet_transaction_add(topo->ld->wallet, tx->wtx,
 					       b->height, i);
 		}

lightningd/dual_open_control.c

@@ -1461,7 +1461,8 @@ static void handle_tx_broadcast(struct channel_send *cs)
 
 	/* This might have spent UTXOs from our wallet */
 	num_utxos = wallet_extract_owned_outputs(ld->wallet,
-						 wtx, NULL,
+						 /* FIXME: what txindex? */
+						 wtx, 1, NULL,
 						 &unused);
 	if (num_utxos)
 		wallet_transaction_add(ld->wallet, wtx, 0, 0);

tests/test_opening.py

@@ -1909,7 +1909,6 @@ def test_zeroreserve_alldust(node_factory):
     l1.rpc.fundchannel(l2.info['id'], minfunding + 1)
 
 
-@pytest.mark.xfail
 def test_coinbase_unspendable(node_factory, bitcoind):
     """ A node should not be able to spend a coinbase output
         before it's mature """
@@ -1923,6 +1922,29 @@ def test_coinbase_unspendable(node_factory, bitcoind):
 
     # Wait til money in wallet
     wait_for(lambda: len(l1.rpc.listfunds()['outputs']) == 1)
-    l1.rpc.withdraw(addr2, "all")
+    out = only_one(l1.rpc.listfunds()['outputs'])
+    assert out['status'] == 'immature'
+
+    with pytest.raises(RpcError, match='Could not afford all using all 0 available UTXOs'):
+        l1.rpc.withdraw(addr2, "all")
+
     # Nothing sent to the mempool!
     assert len(bitcoind.rpc.getrawmempool()) == 0
+
+    # Mine 98 blocks
+    bitcoind.rpc.generatetoaddress(98, l1.rpc.newaddr()['bech32'])
+    assert len([out for out in l1.rpc.listfunds()['outputs'] if out['status'] == 'confirmed']) == 0
+    with pytest.raises(RpcError, match='Could not afford all using all 0 available UTXOs'):
+        l1.rpc.withdraw(addr2, "all")
+
+    # One more and the first coinbase unlocks
+    bitcoind.rpc.generatetoaddress(1, l1.rpc.newaddr()['bech32'])
+    wait_for(lambda: len(l1.rpc.listfunds()['outputs']) == 100)
+    assert len([out for out in l1.rpc.listfunds()['outputs'] if out['status'] == 'confirmed']) == 1
+    l1.rpc.withdraw(addr2, "all")
+    # One tx in the mempool now!
+    assert len(bitcoind.rpc.getrawmempool()) == 1
+
+    # Mine one block, assert one more is spendable
+    bitcoind.rpc.generatetoaddress(1, l1.rpc.newaddr()['bech32'])
+    assert len([out for out in l1.rpc.listfunds()['outputs'] if out['status'] == 'confirmed']) == 1

wallet/db.c

@@ -929,6 +929,7 @@ static struct migration dbmigrations[] = {
     /* Adds scid column, then moves short_channel_id across to it */
     {SQL("ALTER TABLE channels ADD scid BIGINT;"), migrate_channels_scids_as_integers},
     {SQL("ALTER TABLE payments ADD failscid BIGINT;"), migrate_payments_scids_as_integers},
+    {SQL("ALTER TABLE outputs ADD is_in_coinbase INTEGER DEFAULT 0;"), NULL},
 };
 
 /* Released versions are of form v{num}[.{num}]* */

wallet/wallet.c

@@ -148,7 +148,8 @@ static bool wallet_add_utxo(struct wallet *w, struct utxo *utxo,
 		       ", confirmation_height"
 		       ", spend_height"
 		       ", scriptpubkey"
-		       ") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);"));
+		       ", is_in_coinbase"
+		       ") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);"));
 	db_bind_txid(stmt, 0, &utxo->outpoint.txid);
 	db_bind_int(stmt, 1, utxo->outpoint.n);
 	db_bind_amount_sat(stmt, 2, &utxo->amount);
@@ -183,6 +184,7 @@ static bool wallet_add_utxo(struct wallet *w, struct utxo *utxo,
 	db_bind_blob(stmt, 12, utxo->scriptPubkey,
 			  tal_bytelen(utxo->scriptPubkey));
 
+	db_bind_int(stmt, 13, utxo->is_in_coinbase);
 	db_exec_prepared_v2(take(stmt));
 	return true;
 }
@@ -200,6 +202,9 @@ static struct utxo *wallet_stmt2output(const tal_t *ctx, struct db_stmt *stmt)
 	utxo->is_p2sh = db_col_int(stmt, "type") == p2sh_wpkh;
 	utxo->status = db_col_int(stmt, "status");
 	utxo->keyindex = db_col_int(stmt, "keyindex");
+
+	utxo->is_in_coinbase = db_col_int(stmt, "is_in_coinbase") == 1;
+
 	if (!db_col_is_null(stmt, "channel_id")) {
 		utxo->close_info = tal(utxo, struct unilateral_close_info);
 		utxo->close_info->channel_id = db_col_u64(stmt, "channel_id");
@@ -297,6 +302,7 @@ struct utxo **wallet_get_utxos(const tal_t *ctx, struct wallet *w, const enum ou
 						", scriptpubkey "
 						", reserved_til "
 						", csv_lock "
+						", is_in_coinbase "
 						"FROM outputs"));
 	} else {
 		stmt = db_prepare_v2(w->db, SQL("SELECT"
@@ -315,6 +321,7 @@ struct utxo **wallet_get_utxos(const tal_t *ctx, struct wallet *w, const enum ou
 						", scriptpubkey "
 						", reserved_til "
 						", csv_lock "
+						", is_in_coinbase "
 						"FROM outputs "
 						"WHERE status= ? "));
 		db_bind_int(stmt, 0, output_status_in_db(state));
@@ -354,6 +361,7 @@ struct utxo **wallet_get_unconfirmed_closeinfo_utxos(const tal_t *ctx,
 					", scriptpubkey"
 					", reserved_til"
 					", csv_lock"
+					", is_in_coinbase"
 					" FROM outputs"
 					" WHERE channel_id IS NOT NULL AND "
 					"confirmation_height IS NULL"));
@@ -391,6 +399,7 @@ struct utxo *wallet_utxo_get(const tal_t *ctx, struct wallet *w,
 					", scriptpubkey"
 					", reserved_til"
 					", csv_lock"
+					", is_in_coinbase"
 					" FROM outputs"
 					" WHERE prev_out_tx = ?"
 					" AND prev_out_index = ?"));
@@ -501,6 +510,17 @@ static bool deep_enough(u32 maxheight, const struct utxo *utxo,
 		if (csv_free > current_blockheight)
 			return false;
 	}
+
+	/* If the utxo is a coinbase, we over-write the maxheight
+	 * to the coinbase maxheight (current - 99) */
+	if (utxo->is_in_coinbase) {
+		/* Nothing is spendable the first 100 blocks */
+		if (current_blockheight < 100)
+			return false;
+		if (maxheight > current_blockheight - 99)
+			maxheight = current_blockheight - 99;
+	}
+
 	/* If we require confirmations check that we have a
 	 * confirmation height and that it is below the required
 	 * maxheight (current_height - minconf) */
@@ -539,6 +559,7 @@ struct utxo *wallet_find_utxo(const tal_t *ctx, struct wallet *w,
 					", scriptpubkey "
 					", reserved_til"
 					", csv_lock"
+					", is_in_coinbase"
 					" FROM outputs"
 					" WHERE status = ?"
 					" OR (status = ? AND reserved_til <= ?)"
@@ -2296,6 +2317,7 @@ void wallet_confirm_tx(struct wallet *w,
 }
 
 int wallet_extract_owned_outputs(struct wallet *w, const struct wally_tx *wtx,
+				 u32 tx_index,
 				 const u32 *blockheight,
 				 struct amount_sat *total)
 {
@@ -2330,19 +2352,21 @@ int wallet_extract_owned_outputs(struct wallet *w, const struct wally_tx *wtx,
 		wally_txid(wtx, &utxo->outpoint.txid);
 		utxo->outpoint.n = output;
 		utxo->close_info = NULL;
+		utxo->is_in_coinbase = tx_index == 0;
 
 		utxo->blockheight = blockheight ? blockheight : NULL;
 		utxo->spendheight = NULL;
 		utxo->scriptPubkey = tal_dup_talarr(utxo, u8, script);
 
-		log_debug(w->log, "Owning output %zu %s (%s) txid %s%s",
+		log_debug(w->log, "Owning output %zu %s (%s) txid %s%s%s",
 			  output,
 			  type_to_string(tmpctx, struct amount_sat,
 					 &utxo->amount),
 			  is_p2sh ? "P2SH" : "SEGWIT",
 			  type_to_string(tmpctx, struct bitcoin_txid,
 					 &utxo->outpoint.txid),
-			  blockheight ? " CONFIRMED" : "");
+			  blockheight ? " CONFIRMED" : "",
+			  tx_index == 0 ? " COINBASE" : "");
 
 		/* We only record final ledger movements */
 		if (blockheight) {

wallet/wallet.h

@@ -685,6 +685,7 @@ void wallet_blocks_heights(struct wallet *w, u32 def, u32 *min, u32 *max);
  * wallet_extract_owned_outputs - given a tx, extract all of our outputs
  */
 int wallet_extract_owned_outputs(struct wallet *w, const struct wally_tx *tx,
+				 u32 tx_index,
 				 const u32 *blockheight,
 				 struct amount_sat *total);
 

wallet/walletrpc.c

@@ -240,6 +240,7 @@ static void json_add_utxo(struct json_stream *response,
 {
 	const char *out;
 	bool reserved;
+	u32 current_height = get_block_height(wallet->ld->topology);
 
 	json_object_start(response, fieldname);
 	json_add_txid(response, "txid", &utxo->outpoint.txid);
@@ -271,13 +272,16 @@ static void json_add_utxo(struct json_stream *response,
 	if (utxo->spendheight)
 		json_add_string(response, "status", "spent");
 	else if (utxo->blockheight) {
-		json_add_string(response, "status", "confirmed");
+		if (utxo->is_in_coinbase
+		    && *utxo->blockheight + 99 > current_height) {
+			json_add_string(response, "status", "immature");
+		} else
+			json_add_string(response, "status", "confirmed");
 		json_add_num(response, "blockheight", *utxo->blockheight);
 	} else
 		json_add_string(response, "status", "unconfirmed");
 
-	reserved = utxo_is_reserved(utxo,
-				    get_block_height(wallet->ld->topology));
+	reserved = utxo_is_reserved(utxo, current_height);
 	json_add_bool(response, "reserved", reserved);
 	if (reserved)
 		json_add_num(response, "reserved_to_block",
@@ -884,7 +888,8 @@ static void sendpsbt_done(struct bitcoind *bitcoind UNUSED,
 	wallet_transaction_add(ld->wallet, sending->wtx, 0, 0);
 
 	/* Extract the change output and add it to the DB */
-	wallet_extract_owned_outputs(ld->wallet, sending->wtx, NULL, &change);
+	/* FIXME: what txindex? */
+	wallet_extract_owned_outputs(ld->wallet, sending->wtx, 1, NULL, &change);
 	wally_txid(sending->wtx, &txid);
 
 	for (size_t i = 0; i < sending->psbt->num_outputs; i++)