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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

24,966 bytes · SHA-256 edbad2e7ffd437b0… · View upstream ↗

1#!/usr/bin/env python3
2# Copyright (c) 2024-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
6from decimal import Decimal
7
8from test_framework.messages import (
9    COIN,
10    CTxOut,
11)
12from test_framework.test_framework import BitcoinTestFramework
13from test_framework.mempool_util import assert_mempool_contents
14from test_framework.util import (
15    assert_equal,
16    assert_greater_than,
17    assert_raises_rpc_error,
18    assert_not_equal,
19)
20from test_framework.wallet import (
21    MiniWallet,
22)
23from test_framework.blocktools import (
24    create_empty_fork
25)
26
27class EphemeralDustTest(BitcoinTestFramework):
28    def set_test_params(self):
29        # Mempools should match via 1P1C p2p relay
30        self.num_nodes = 2
31
32        # Don't test trickling logic
33        self.noban_tx_relay = True
34
35    def add_output_to_create_multi_result(self, result, output_value=0):
36        """ Add output without changing absolute tx fee
37        """
38        assert len(result["tx"].vout) > 0
39        assert result["tx"].vout[0].nValue >= output_value
40        result["tx"].vout.append(CTxOut(output_value, result["tx"].vout[0].scriptPubKey))
41        # Take value from first output
42        result["tx"].vout[0].nValue -= output_value
43        result["new_utxos"][0]["value"] = Decimal(result["tx"].vout[0].nValue) / COIN
44        new_txid = result["tx"].txid_hex
45        result["txid"]  = new_txid
46        result["wtxid"] = result["tx"].wtxid_hex
47        result["hex"] = result["tx"].serialize().hex()
48        for new_utxo in result["new_utxos"]:
49            new_utxo["txid"] = new_txid
50            new_utxo["wtxid"] = result["tx"].wtxid_hex
51
52        result["new_utxos"].append({"txid": new_txid, "vout": len(result["tx"].vout) - 1, "value": Decimal(output_value) / COIN, "height": 0, "coinbase": False, "confirmations": 0})
53
54    def create_ephemeral_dust_package(self, *, tx_version, dust_tx_fee=0, dust_value=0, num_dust_outputs=1, extra_sponsors=None):
55        """Creates a 1P1C package containing ephemeral dust. By default, the parent transaction
56           is zero-fee and creates a single zero-value dust output, and all of its outputs are
57           spent by the child."""
58        dusty_tx = self.wallet.create_self_transfer_multi(fee_per_output=dust_tx_fee, version=tx_version)
59        for _ in range(num_dust_outputs):
60            self.add_output_to_create_multi_result(dusty_tx, dust_value)
61
62        extra_sponsors = extra_sponsors or []
63        sweep_tx = self.wallet.create_self_transfer_multi(
64            utxos_to_spend=dusty_tx["new_utxos"] + extra_sponsors,
65            version=tx_version,
66        )
67
68        return dusty_tx, sweep_tx
69
70    def trigger_reorg(self, fork_blocks):
71        """Trigger reorg of the fork blocks."""
72        for block in fork_blocks:
73            self.nodes[0].submitblock(block.serialize().hex())
74        assert_equal(self.nodes[0].getbestblockhash(), fork_blocks[-1].hash_hex)
75
76    def run_test(self):
77
78        node = self.nodes[0]
79        self.wallet = MiniWallet(node)
80
81        self.test_normal_dust()
82        self.test_sponsor_cycle()
83        self.test_node_restart()
84        self.test_fee_having_parent()
85        self.test_multidust()
86        self.test_nonzero_dust()
87        self.test_non_truc()
88        self.test_unspent_ephemeral()
89        self.test_reorgs()
90        self.test_no_minrelay_fee()
91
92    def test_normal_dust(self):
93        self.log.info("Create 0-value dusty output, show that it works inside truc when spent in package")
94
95        assert_equal(self.nodes[0].getrawmempool(), [])
96        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=3)
97
98        # Test doesn't work because lack of package feerates
99        test_res = self.nodes[0].testmempoolaccept([dusty_tx["hex"], sweep_tx["hex"]])
100        assert not test_res[0]["allowed"]
101        assert_equal(test_res[0]["reject-reason"], "min relay fee not met")
102
103        # And doesn't work on its own
104        assert_raises_rpc_error(-26, "min relay fee not met", self.nodes[0].sendrawtransaction, dusty_tx["hex"])
105
106        # If we add modified fees, it is still not allowed due to dust check
107        self.nodes[0].prioritisetransaction(txid=dusty_tx["txid"], dummy=0, fee_delta=COIN)
108        test_res = self.nodes[0].testmempoolaccept([dusty_tx["hex"]])
109        assert not test_res[0]["allowed"]
110        assert_equal(test_res[0]["reject-reason"], "dust")
111        # Reset priority
112        self.nodes[0].prioritisetransaction(txid=dusty_tx["txid"], dummy=0, fee_delta=-COIN)
113        assert_equal(self.nodes[0].getprioritisedtransactions(), {})
114
115        # Package evaluation succeeds
116        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
117        assert_equal(res["package_msg"], "success")
118        assert_mempool_contents(self, self.nodes[0], expected=[dusty_tx["tx"], sweep_tx["tx"]])
119
120        # Entry is denied when non-0-fee, either base or unmodified.
121        # If in-mempool, we're not allowed to prioritise due to detected dust output
122        assert_raises_rpc_error(-8, "Priority is not supported for transactions with dust outputs.", self.nodes[0].prioritisetransaction, dusty_tx["txid"], 0, 1)
123        assert_equal(self.nodes[0].getprioritisedtransactions(), {})
124
125        self.generate(self.nodes[0], 1)
126        assert_equal(self.nodes[0].getrawmempool(), [])
127
128    def test_node_restart(self):
129        self.log.info("Test that an ephemeral package is rejected on restart due to individual evaluation")
130
131        assert_equal(self.nodes[0].getrawmempool(), [])
132        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=3)
133
134        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
135        assert_equal(res["package_msg"], "success")
136        assert_equal(len(self.nodes[0].getrawmempool()), 2)
137        assert_mempool_contents(self, self.nodes[0], expected=[dusty_tx["tx"], sweep_tx["tx"]])
138
139        # Node restart; doesn't allow ephemeral transaction back in due to individual submission
140        # resulting in 0-fee. Supporting re-submission of CPFP packages on restart is desired but not
141        # yet implemented.
142        self.restart_node(0)
143        self.restart_node(1)
144        self.connect_nodes(0, 1)
145        assert_mempool_contents(self, self.nodes[0], expected=[])
146
147    def test_fee_having_parent(self):
148        self.log.info("Test that a transaction with ephemeral dust may not have non-0 base fee")
149
150        assert_equal(self.nodes[0].getrawmempool(), [])
151
152        sats_fee = 1
153        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=3, dust_tx_fee=sats_fee)
154        assert_equal(int(COIN * dusty_tx["fee"]), sats_fee) # has fees
155        assert_greater_than(dusty_tx["tx"].vout[0].nValue, 330) # main output is not dust
156        assert_equal(dusty_tx["tx"].vout[1].nValue, 0) # added one is dust
157
158        # When base fee is non-0, we report dust like usual
159        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
160        assert_equal(res["package_msg"], "transaction failed")
161        assert_equal(res["tx-results"][dusty_tx["wtxid"]]["error"], "dust, tx with dust output must be 0-fee")
162
163        # Priority is ignored: rejected even if modified fee is 0
164        self.nodes[0].prioritisetransaction(txid=dusty_tx["txid"], dummy=0, fee_delta=-sats_fee)
165        self.nodes[1].prioritisetransaction(txid=dusty_tx["txid"], dummy=0, fee_delta=-sats_fee)
166        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
167        assert_equal(res["package_msg"], "transaction failed")
168        assert_equal(res["tx-results"][dusty_tx["wtxid"]]["error"], "dust, tx with dust output must be 0-fee")
169
170        # Will not be accepted if base fee is 0 with modified fee of non-0
171        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=3)
172
173        self.nodes[0].prioritisetransaction(txid=dusty_tx["txid"], dummy=0, fee_delta=1000)
174        self.nodes[1].prioritisetransaction(txid=dusty_tx["txid"], dummy=0, fee_delta=1000)
175
176        # It's rejected submitted alone
177        test_res = self.nodes[0].testmempoolaccept([dusty_tx["hex"]])
178        assert not test_res[0]["allowed"]
179        assert_equal(test_res[0]["reject-reason"], "dust")
180
181        # Or as a package
182        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
183        assert_equal(res["package_msg"], "transaction failed")
184        assert_equal(res["tx-results"][dusty_tx["wtxid"]]["error"], "dust, tx with dust output must be 0-fee")
185
186        assert_mempool_contents(self, self.nodes[0], expected=[])
187
188    def test_multidust(self):
189        self.log.info("Test that a transaction with multiple ephemeral dusts is not allowed")
190
191        assert_mempool_contents(self, self.nodes[0], expected=[])
192        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=3, num_dust_outputs=2)
193
194        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
195        assert_equal(res["package_msg"], "transaction failed")
196        assert_equal(res["tx-results"][dusty_tx["wtxid"]]["error"], "dust")
197        assert_equal(self.nodes[0].getrawmempool(), [])
198
199    def test_nonzero_dust(self):
200        self.log.info("Test that a single output of any satoshi amount is allowed, not checking spending")
201
202        # We aren't checking spending, allow it in with no fee
203        self.restart_node(0, extra_args=["-minrelaytxfee=0"])
204        self.restart_node(1, extra_args=["-minrelaytxfee=0"])
205        self.connect_nodes(0, 1)
206
207        # 330 is dust threshold for taproot outputs
208        for value in [1, 329, 330]:
209            assert_equal(self.nodes[0].getrawmempool(), [])
210            dusty_tx, _ = self.create_ephemeral_dust_package(tx_version=3, dust_value=value)
211            test_res = self.nodes[0].testmempoolaccept([dusty_tx["hex"]])
212            assert test_res[0]["allowed"]
213
214        self.restart_node(0, extra_args=[])
215        self.restart_node(1, extra_args=[])
216        self.connect_nodes(0, 1)
217        assert_mempool_contents(self, self.nodes[0], expected=[])
218
219    def test_non_truc(self):
220        self.log.info("Test that v2 dust-having transaction is also accepted if spent")
221
222        assert_equal(self.nodes[0].getrawmempool(), [])
223        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=2)
224
225        res = self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
226        assert_equal(res["package_msg"], "success")
227        assert_mempool_contents(self, self.nodes[0], expected=[dusty_tx["tx"], sweep_tx["tx"]])
228        self.generate(self.nodes[0], 1)
229
230    def test_unspent_ephemeral(self):
231        self.log.info("Test that spending from a tx with ephemeral outputs is only allowed if dust is spent as well")
232
233        assert_equal(self.nodes[0].getrawmempool(), [])
234        dusty_tx, sweep_tx = self.create_ephemeral_dust_package(tx_version=3, dust_value=329)
235
236        # Valid sweep we will RBF incorrectly by not spending dust as well
237        self.nodes[0].submitpackage([dusty_tx["hex"], sweep_tx["hex"]])
238        assert_mempool_contents(self, self.nodes[0], expected=[dusty_tx["tx"], sweep_tx["tx"]])
239
240        # Doesn't spend in-mempool dust output from parent
241        unspent_sweep_tx = self.wallet.create_self_transfer_multi(fee_per_output=2000, utxos_to_spend=[dusty_tx["new_utxos"][0]], version=3)
242        assert_greater_than(unspent_sweep_tx["fee"], sweep_tx["fee"])
243        res = self.nodes[0].submitpackage([dusty_tx["hex"], unspent_sweep_tx["hex"]])
244        assert_equal(res["tx-results"][unspent_sweep_tx["wtxid"]]["error"], f"missing-ephemeral-spends, tx {unspent_sweep_tx['txid']} (wtxid={unspent_sweep_tx['wtxid']}) did not spend parent's ephemeral dust")
245        assert_raises_rpc_error(-26, f"missing-ephemeral-spends, tx {unspent_sweep_tx['txid']} (wtxid={unspent_sweep_tx['wtxid']}) did not spend parent's ephemeral dust", self.nodes[0].sendrawtransaction, unspent_sweep_tx["hex"])
246        assert_mempool_contents(self, self.nodes[0], expected=[dusty_tx["tx"], sweep_tx["tx"]])
247
248        # Spend works with dust spent
249        sweep_tx_2 = self.wallet.create_self_transfer_multi(fee_per_output=2000, utxos_to_spend=dusty_tx["new_utxos"], version=3)
250        assert_not_equal(sweep_tx["hex"], sweep_tx_2["hex"])

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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