Merge bitcoin/bitcoin#21365: Basic Taproot signing support for descriptor wallets

458a345b0590fd2fa04c7d8d70beb8d57e34bbc8 Add support for SIGHASH_DEFAULT in RPCs, and make it default (Pieter Wuille)
c0f0c8eccb04f90940007e0c6aaff56bf2ab35b5 tests: check spending of P2TR (Pieter Wuille)
a2380127e905e5849f90acc7c69832859d8336aa Basic Taproot signing logic in script/sign.cpp (Pieter Wuille)
49487bc3b6038393c1b9c2dbdc04a78ae1178f1a Make GetInputUTXO safer: verify non-witness UTXO match (Pieter Wuille)
fd3f6890f3dfd683f6f13db912caf5c4288adf08 Construct and use PrecomputedTransactionData in PSBT signing (Pieter Wuille)
5cb6502ac5730ea453edbec4c46027ac2ada97e0 Construct and use PrecomputedTransactionData in SignTransaction (Pieter Wuille)
5d2e22437b22e7465ae4be64069443bcc1769dc9 Don't nuke witness data when signing fails (Pieter Wuille)
ce9353164bdb6215a62b2b6dcb2121d331796f60 Permit full precomputation in PrecomputedTransactionData (Pieter Wuille)
e841fb503d7a662bde01ec2e4794faa989265950 Add precomputed txdata support to MutableTransactionSignatureCreator (Pieter Wuille)
a91d532338ecb66ec5bed164929d878dd55d63a4 Add CKey::SignSchnorr function for BIP 340/341 signing (Pieter Wuille)
e77a2839b54fa2039bba468e8c09dbbbf19b150a Use HandleMissingData also in CheckSchnorrSignature (Pieter Wuille)
dbb0ce9fbff01ffe4dd29da465f43ecaddc2854c Add TaprootSpendData data structure, equivalent to script map for P2[W]SH (Pieter Wuille)

Pull request description:

  Builds on top of #22051, adding signing support after derivation support.

  Nothing is changed in descriptor features. Signing works for key path and script path spending, through the normal sending functions, and PSBT-based RPCs. However, PSBT usability is rather low as no extensions have been defined to convey Taproot-specific information, so all script information must be known to the signing wallet.

ACKs for top commit:
  achow101:
    re-ACK 458a345b0590fd2fa04c7d8d70beb8d57e34bbc8
  fjahr:
    Code review ACK 458a345b0590fd2fa04c7d8d70beb8d57e34bbc8
  Sjors:
    ACK 458a345b0590fd2fa04c7d8d70beb8d57e34bbc8

Tree-SHA512: 30ed212cf7754763a4a81624ebc084c51727b8322711ac0b390369213c1a891d367ed8b123882ac08c99595320c11ec57ee42304ff22a69afdc3d1a0d55cc711

1 files changed, 116 insertions, 10 deletions

diff --git a/test/functional/wallet_taproot.py b/test/functional/wallet_taproot.py
index 5803c0cf54..1547a90125 100755
--- a/test/functional/wallet_taproot.py
+++ b/test/functional/wallet_taproot.py
@@ -6,6 +6,7 @@
 
 import random
 
+from decimal import Decimal
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import assert_equal
 from test_framework.descriptors import descsum_create
@@ -233,20 +234,85 @@ class WalletTaprootTest(BitcoinTestFramework):
         # tr descriptors cannot be imported when Taproot is not active
         result = self.privs_tr_enabled.importdescriptors([{"desc": desc, "timestamp": "now"}])
         assert(result[0]["success"])
-        result = self.privs_tr_disabled.importdescriptors([{"desc": desc, "timestamp": "now"}])
-        assert(not result[0]["success"])
-        assert_equal(result[0]["error"]["code"], -4)
-        assert_equal(result[0]["error"]["message"], "Cannot import tr() descriptor when Taproot is not active")
         result = self.pubs_tr_enabled.importdescriptors([{"desc": desc_pub, "timestamp": "now"}])
         assert(result[0]["success"])
-        result = self.pubs_tr_disabled.importdescriptors([{"desc": desc_pub, "timestamp": "now"}])
-        assert(not result[0]["success"])
-        assert_equal(result[0]["error"]["code"], -4)
-        assert_equal(result[0]["error"]["message"], "Cannot import tr() descriptor when Taproot is not active")
+        if desc.startswith("tr"):
+            result = self.privs_tr_disabled.importdescriptors([{"desc": desc, "timestamp": "now"}])
+            assert(not result[0]["success"])
+            assert_equal(result[0]["error"]["code"], -4)
+            assert_equal(result[0]["error"]["message"], "Cannot import tr() descriptor when Taproot is not active")
+            result = self.pubs_tr_disabled.importdescriptors([{"desc": desc_pub, "timestamp": "now"}])
+            assert(not result[0]["success"])
+            assert_equal(result[0]["error"]["code"], -4)
+            assert_equal(result[0]["error"]["message"], "Cannot import tr() descriptor when Taproot is not active")
+
+    def do_test_sendtoaddress(self, comment, pattern, privmap, treefn, keys_pay, keys_change):
+        self.log.info("Testing %s through sendtoaddress" % comment)
+        desc_pay = self.make_desc(pattern, privmap, keys_pay)
+        desc_change = self.make_desc(pattern, privmap, keys_change)
+        desc_pay_pub = self.make_desc(pattern, privmap, keys_pay, True)
+        desc_change_pub = self.make_desc(pattern, privmap, keys_change, True)
+        assert_equal(self.nodes[0].getdescriptorinfo(desc_pay)['descriptor'], desc_pay_pub)
+        assert_equal(self.nodes[0].getdescriptorinfo(desc_change)['descriptor'], desc_change_pub)
+        result = self.rpc_online.importdescriptors([{"desc": desc_pay, "active": True, "timestamp": "now"}])
+        assert(result[0]['success'])
+        result = self.rpc_online.importdescriptors([{"desc": desc_change, "active": True, "timestamp": "now", "internal": True}])
+        assert(result[0]['success'])
+        for i in range(4):
+            addr_g = self.rpc_online.getnewaddress(address_type='bech32')
+            if treefn is not None:
+                addr_r = self.make_addr(treefn, keys_pay, i)
+                assert_equal(addr_g, addr_r)
+            boring_balance = int(self.boring.getbalance() * 100000000)
+            to_amnt = random.randrange(1000000, boring_balance)
+            self.boring.sendtoaddress(address=addr_g, amount=Decimal(to_amnt) / 100000000, subtractfeefromamount=True)
+            self.nodes[0].generatetoaddress(1, self.boring.getnewaddress())
+            test_balance = int(self.rpc_online.getbalance() * 100000000)
+            ret_amnt = random.randrange(100000, test_balance)
+            res = self.rpc_online.sendtoaddress(address=self.boring.getnewaddress(), amount=Decimal(ret_amnt) / 100000000, subtractfeefromamount=True)
+            self.nodes[0].generatetoaddress(1, self.boring.getnewaddress())
+            assert(self.rpc_online.gettransaction(res)["confirmations"] > 0)
+
+    def do_test_psbt(self, comment, pattern, privmap, treefn, keys_pay, keys_change):
+        self.log.info("Testing %s through PSBT" % comment)
+        desc_pay = self.make_desc(pattern, privmap, keys_pay, False)
+        desc_change = self.make_desc(pattern, privmap, keys_change, False)
+        desc_pay_pub = self.make_desc(pattern, privmap, keys_pay, True)
+        desc_change_pub = self.make_desc(pattern, privmap, keys_change, True)
+        assert_equal(self.nodes[0].getdescriptorinfo(desc_pay)['descriptor'], desc_pay_pub)
+        assert_equal(self.nodes[0].getdescriptorinfo(desc_change)['descriptor'], desc_change_pub)
+        result = self.psbt_online.importdescriptors([{"desc": desc_pay_pub, "active": True, "timestamp": "now"}])
+        assert(result[0]['success'])
+        result = self.psbt_online.importdescriptors([{"desc": desc_change_pub, "active": True, "timestamp": "now", "internal": True}])
+        assert(result[0]['success'])
+        result = self.psbt_offline.importdescriptors([{"desc": desc_pay, "active": True, "timestamp": "now"}])
+        assert(result[0]['success'])
+        result = self.psbt_offline.importdescriptors([{"desc": desc_change, "active": True, "timestamp": "now", "internal": True}])
+        assert(result[0]['success'])
+        for i in range(4):
+            addr_g = self.psbt_online.getnewaddress(address_type='bech32')
+            if treefn is not None:
+                addr_r = self.make_addr(treefn, keys_pay, i)
+                assert_equal(addr_g, addr_r)
+            boring_balance = int(self.boring.getbalance() * 100000000)
+            to_amnt = random.randrange(1000000, boring_balance)
+            self.boring.sendtoaddress(address=addr_g, amount=Decimal(to_amnt) / 100000000, subtractfeefromamount=True)
+            self.nodes[0].generatetoaddress(1, self.boring.getnewaddress())
+            test_balance = int(self.psbt_online.getbalance() * 100000000)
+            ret_amnt = random.randrange(100000, test_balance)
+            psbt = self.psbt_online.walletcreatefundedpsbt([], [{self.boring.getnewaddress(): Decimal(ret_amnt) / 100000000}], None, {"subtractFeeFromOutputs":[0]})['psbt']
+            res = self.psbt_offline.walletprocesspsbt(psbt)
+            assert(res['complete'])
+            rawtx = self.nodes[0].finalizepsbt(res['psbt'])['hex']
+            txid = self.nodes[0].sendrawtransaction(rawtx)
+            self.nodes[0].generatetoaddress(1, self.boring.getnewaddress())
+            assert(self.psbt_online.gettransaction(txid)['confirmations'] > 0)
 
     def do_test(self, comment, pattern, privmap, treefn, nkeys):
-        keys = self.rand_keys(nkeys)
-        self.do_test_addr(comment, pattern, privmap, treefn, keys)
+        keys = self.rand_keys(nkeys * 4)
+        self.do_test_addr(comment, pattern, privmap, treefn, keys[0:nkeys])
+        self.do_test_sendtoaddress(comment, pattern, privmap, treefn, keys[0:nkeys], keys[nkeys:2*nkeys])
+        self.do_test_psbt(comment, pattern, privmap, treefn, keys[2*nkeys:3*nkeys], keys[3*nkeys:4*nkeys])
 
     def run_test(self):
         self.log.info("Creating wallets...")
@@ -258,8 +324,20 @@ class WalletTaprootTest(BitcoinTestFramework):
         self.pubs_tr_enabled = self.nodes[0].get_wallet_rpc("pubs_tr_enabled")
         self.nodes[2].createwallet(wallet_name="pubs_tr_disabled", descriptors=True, blank=True, disable_private_keys=True)
         self.pubs_tr_disabled=self.nodes[2].get_wallet_rpc("pubs_tr_disabled")
+        self.nodes[0].createwallet(wallet_name="boring")
         self.nodes[0].createwallet(wallet_name="addr_gen", descriptors=True, disable_private_keys=True, blank=True)
+        self.nodes[0].createwallet(wallet_name="rpc_online", descriptors=True, blank=True)
+        self.nodes[0].createwallet(wallet_name="psbt_online", descriptors=True, disable_private_keys=True, blank=True)
+        self.nodes[1].createwallet(wallet_name="psbt_offline", descriptors=True, blank=True)
+        self.boring = self.nodes[0].get_wallet_rpc("boring")
         self.addr_gen = self.nodes[0].get_wallet_rpc("addr_gen")
+        self.rpc_online = self.nodes[0].get_wallet_rpc("rpc_online")
+        self.psbt_online = self.nodes[0].get_wallet_rpc("psbt_online")
+        self.psbt_offline = self.nodes[1].get_wallet_rpc("psbt_offline")
+
+        self.log.info("Mining blocks...")
+        gen_addr = self.boring.getnewaddress()
+        self.nodes[0].generatetoaddress(101, gen_addr)
 
         self.do_test(
             "tr(XPRV)",
@@ -276,6 +354,13 @@ class WalletTaprootTest(BitcoinTestFramework):
             1
         )
         self.do_test(
+            "wpkh(XPRV)",
+            "wpkh($1/*)",
+            [True],
+            None,
+            1
+        )
+        self.do_test(
             "tr(XPRV,{H,{H,XPUB}})",
             "tr($1/*,{pk($H),{pk($H),pk($2/*)}})",
             [True, False],
@@ -283,6 +368,13 @@ class WalletTaprootTest(BitcoinTestFramework):
             2
         )
         self.do_test(
+            "wsh(multi(1,XPRV,XPUB))",
+            "wsh(multi(1,$1/*,$2/*))",
+            [True, False],
+            None,
+            2
+        )
+        self.do_test(
             "tr(XPUB,{{H,{H,XPUB}},{H,{H,{H,XPRV}}}})",
             "tr($1/*,{{pk($H),{pk($H),pk($2/*)}},{pk($H),{pk($H),{pk($H),pk($3/*)}}}})",
             [False, False, True],
@@ -290,5 +382,19 @@ class WalletTaprootTest(BitcoinTestFramework):
             3
         )
 
+        self.log.info("Sending everything back...")
+
+        txid = self.rpc_online.sendtoaddress(address=self.boring.getnewaddress(), amount=self.rpc_online.getbalance(), subtractfeefromamount=True)
+        self.nodes[0].generatetoaddress(1, self.boring.getnewaddress())
+        assert(self.rpc_online.gettransaction(txid)["confirmations"] > 0)
+
+        psbt = self.psbt_online.walletcreatefundedpsbt([], [{self.boring.getnewaddress(): self.psbt_online.getbalance()}], None, {"subtractFeeFromOutputs": [0]})['psbt']
+        res = self.psbt_offline.walletprocesspsbt(psbt)
+        assert(res['complete'])
+        rawtx = self.nodes[0].finalizepsbt(res['psbt'])['hex']
+        txid = self.nodes[0].sendrawtransaction(rawtx)
+        self.nodes[0].generatetoaddress(1, self.boring.getnewaddress())
+        assert(self.psbt_online.gettransaction(txid)['confirmations'] > 0)
+
 if __name__ == '__main__':
     WalletTaprootTest().main()