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1#!/usr/bin/env python3
2# Copyright (c) 2021-present The Bitcoin Core developers
3# Distributed under the MIT software license, see the accompanying
4# file COPYING or http://www.opensource.org/licenses/mit-license.php.
5"""Test a basic M-of-N multisig setup between multiple people using descriptor wallets and PSBTs, as well as a signing flow.
6
7This is meant to be documentation as much as functional tests, so it is kept as simple and readable as possible.
8"""
9
10from test_framework.test_framework import BitcoinTestFramework
11from test_framework.util import (
12    assert_approx,
13    assert_equal,
14)
15
16from test_framework.descriptors import descsum_create
17
18
19class WalletMultisigDescriptorPSBTTest(BitcoinTestFramework):
20    def set_test_params(self):
21        self.num_nodes = 1
22        self.setup_clean_chain = True
23        self.extra_args = [["-keypool=100"]]
24
25    def skip_test_if_missing_module(self):
26        self.skip_if_no_wallet()
27
28    @staticmethod
29    def _get_xpub(wallet):
30        """Derive an xpub at m/44h/1h/0h using `derivehdkey`. This derivation matches the `pkh` descriptor since it's least likely to be accidentally reused (legacy addresses)."""
31        # Ideally we would use m/87h/1h/0h but the wallet currently can't sign
32        # for a derivation path that's not used in one of its descriptors.
33        hdkey_info = wallet.derivehdkey("m/44h/1h/0h")
34        # Keep all key origin information (master key fingerprint and all derivation steps) for proper support of hardware devices
35        # See section 'Key origin identification' in 'doc/descriptors.md' for more details...
36        return f"{hdkey_info['origin']}{hdkey_info['xpub']}/<0;1>/*"
37
38    @staticmethod
39    def _check_psbt(psbt, to, value, multisig):
40        """Helper function for any of the N participants to check the psbt with decodepsbt and verify it is OK before signing."""
41        decoded = multisig.decodepsbt(psbt)
42        amount = 0
43        for psbt_out in decoded["outputs"]:
44            address = psbt_out["script"]["address"]
45            assert_equal(multisig.getaddressinfo(address)["ischange"], address != to)
46            if address == to:
47                amount += psbt_out["amount"]
48        assert_approx(amount, float(value), vspan=0.001)
49
50    def participants_create_multisigs(self, xpubs):
51        """The multisig is created by importing the following descriptors. The resulting wallet is watch-only and every participant can do this."""
52        for i in range(self.N):
53            self.node.createwallet(wallet_name=f"{self.name}_{i}", blank=True, disable_private_keys=True)
54            multisig = self.node.get_wallet_rpc(f"{self.name}_{i}")
55            desc = descsum_create(f"wsh(sortedmulti({self.M},{','.join(xpubs)}))")
56            self.log.debug(desc)
57            result = multisig.importdescriptors([
58                {
59                    "desc": desc,
60                    "active": True,
61                    "timestamp": "now",
62                },
63            ])
64            assert all(r["success"] for r in result)
65            yield multisig
66
67    def run_test(self):
68        self.M = 2
69        self.N = 3
70        self.node = self.nodes[0]
71        self.name = f"{self.M}_of_{self.N}_multisig"
72        self.log.info(f"Testing {self.name}...")
73
74        participants = {
75            # Every participant generates an xpub. The most straightforward way is to create a new descriptor wallet.
76            # This wallet will be the participant's `signer` for the resulting multisig. Avoid reusing this wallet for any other purpose (for privacy reasons).
77            "signers": [self.node.get_wallet_rpc(self.node.createwallet(wallet_name=f"participant_{i}")["name"]) for i in range(self.N)],
78            # After participants generate and exchange their xpubs they will each create their own watch-only multisig.
79            # Note: these multisigs are all the same, this just highlights that each participant can independently verify everything on their own node.
80            "multisigs": []
81        }
82
83        self.log.info("Generate and exchange xpubs...")
84        xpubs = [self._get_xpub(signer) for signer in participants["signers"]]
85
86        self.log.info("Every participant imports the following descriptors to create the watch-only multisig...")
87        participants["multisigs"] = list(self.participants_create_multisigs(xpubs))
88
89        self.log.info("Check that every participant's multisig generates the same addresses...")
90        for _ in range(10):  # we check that the first 10 generated addresses are the same for all participant's multisigs
91            receive_addresses = [multisig.getnewaddress() for multisig in participants["multisigs"]]
92            for address in receive_addresses:
93                assert_equal(address, receive_addresses[0])
94            change_addresses = [multisig.getrawchangeaddress() for multisig in participants["multisigs"]]
95            for address in change_addresses:
96                assert_equal(address, change_addresses[0])
97
98        self.log.info("Get a mature utxo to send to the multisig...")
99        coordinator_wallet = participants["signers"][0]
100        self.generatetoaddress(self.node, 101, coordinator_wallet.getnewaddress())
101
102        deposit_amount = 6.15
103        multisig_receiving_address = participants["multisigs"][0].getnewaddress()
104        self.log.info("Send funds to the resulting multisig receiving address...")
105        coordinator_wallet.sendtoaddress(multisig_receiving_address, deposit_amount)
106        self.generate(self.node, 1)
107        for participant in participants["multisigs"]:
108            assert_approx(participant.getbalance(), deposit_amount, vspan=0.001)
109
110        self.log.info("Send a transaction from the multisig!")
111        to = participants["signers"][self.N - 1].getnewaddress()
112        value = 1
113        self.log.info("First, make a sending transaction, created using `walletcreatefundedpsbt` (anyone can initiate this)...")
114        psbt = participants["multisigs"][0].walletcreatefundedpsbt(inputs=[], outputs={to: value}, feeRate=0.00010)
115
116        psbts = []
117        self.log.info("Now at least M users check the psbt with decodepsbt and (if OK) signs it with walletprocesspsbt...")
118        for m in range(self.M):
119            signers_multisig = participants["multisigs"][m]
120            self._check_psbt(psbt["psbt"], to, value, signers_multisig)
121            signing_wallet = participants["signers"][m]
122            partially_signed_psbt = signing_wallet.walletprocesspsbt(psbt["psbt"])
123            psbts.append(partially_signed_psbt["psbt"])
124
125        self.log.info("Finally, collect the signed PSBTs with combinepsbt, finalizepsbt, then broadcast the resulting transaction...")
126        combined = coordinator_wallet.combinepsbt(psbts)
127        self.log.debug(coordinator_wallet.analyzepsbt(combined))
128        finalized = coordinator_wallet.finalizepsbt(combined)
129        coordinator_wallet.sendrawtransaction(finalized["hex"])
130
131        self.log.info("Check that balances are correct after the transaction has been included in a block.")
132        self.generate(self.node, 1)
133        assert_approx(participants["multisigs"][0].getbalance(), deposit_amount - value, vspan=0.001)
134        assert_equal(participants["signers"][self.N - 1].getbalance(), value)
135
136        self.log.info("Send another transaction from the multisig, this time with a daisy chained signing flow (one after another in series)!")
137        psbt = participants["multisigs"][0].walletcreatefundedpsbt(inputs=[], outputs={to: value}, feeRate=0.00010)
138        for m in range(self.M):
139            signers_multisig = participants["multisigs"][m]
140            self._check_psbt(psbt["psbt"], to, value, signers_multisig)
141            signing_wallet = participants["signers"][m]
142            psbt = signing_wallet.walletprocesspsbt(psbt["psbt"])
143            assert_equal(psbt["complete"], m == self.M - 1)
144        coordinator_wallet.sendrawtransaction(psbt["hex"])
145
146        self.log.info("Check that balances are correct after the transaction has been included in a block.")
147        self.generate(self.node, 1)
148        assert_approx(participants["multisigs"][0].getbalance(), deposit_amount - (value * 2), vspan=0.001)
149        assert_equal(participants["signers"][self.N - 1].getbalance(), value * 2)
150
151
152if __name__ == "__main__":
153    WalletMultisigDescriptorPSBTTest(__file__).main()
154

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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