READ THE CODE

Inside Bitcoin

The code behind the network, with room to understand it.

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.

25,547 bytes · SHA-256 86f8d6ade8b32847… · View upstream ↗

1#!/usr/bin/env python3
2# Copyright (c) 2017-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 mempool acceptance of raw transactions."""
6
7from copy import deepcopy
8from decimal import Decimal
9import math
10
11from test_framework.test_framework import BitcoinTestFramework
12from test_framework.blocktools import MAX_STANDARD_TX_WEIGHT
13from test_framework.mempool_util import (
14    DEFAULT_MIN_RELAY_TX_FEE,
15    DEFAULT_INCREMENTAL_RELAY_FEE,
16)
17from test_framework.messages import (
18    MAX_BIP125_RBF_SEQUENCE,
19    COIN,
20    COutPoint,
21    CTransaction,
22    CTxIn,
23    CTxInWitness,
24    CTxOut,
25    MAX_BLOCK_WEIGHT,
26    WITNESS_SCALE_FACTOR,
27    MAX_MONEY,
28    SEQUENCE_FINAL,
29    tx_from_hex,
30)
31from test_framework.script import (
32    CScript,
33    OP_0,
34    OP_HASH160,
35    OP_RETURN,
36    OP_TRUE,
37    SIGHASH_ALL,
38    sign_input_legacy,
39)
40from test_framework.script_util import (
41    DUMMY_MIN_OP_RETURN_SCRIPT,
42    keys_to_multisig_script,
43    MIN_PADDING,
44    MIN_STANDARD_TX_NONWITNESS_SIZE,
45    PAY_TO_ANCHOR,
46    script_to_p2sh_script,
47    script_to_p2wsh_script,
48)
49from test_framework.util import (
50    assert_equal,
51    assert_greater_than,
52    assert_raises_rpc_error,
53    sync_txindex,
54)
55from test_framework.wallet import MiniWallet
56from test_framework.wallet_util import generate_keypair
57
58
59class MempoolAcceptanceTest(BitcoinTestFramework):
60    def set_test_params(self):
61        self.num_nodes = 1
62        self.extra_args = [[
63            '-txindex','-permitbaremultisig=0',
64        ]] * self.num_nodes
65        self.supports_cli = False
66
67    def check_mempool_result(self, result_expected, *args, **kwargs):
68        """Wrapper to check result of testmempoolaccept on node_0's mempool"""
69        result_test = self.nodes[0].testmempoolaccept(*args, **kwargs)
70        for r in result_test:
71            # Skip these checks for now
72            r.pop('wtxid')
73            if "fees" in r:
74                r["fees"].pop("effective-feerate")
75                r["fees"].pop("effective-includes")
76            if "reject-details" in r:
77                r.pop("reject-details")
78        assert_equal(result_expected, result_test)
79        assert_equal(self.nodes[0].getmempoolinfo()['size'], self.mempool_size)  # Must not change mempool state
80
81    def run_test(self):
82        node = self.nodes[0]
83        self.wallet = MiniWallet(node)
84
85        assert_equal(node.getmempoolinfo()['permitbaremultisig'], False)
86
87        self.log.info('Start with empty mempool, and 200 blocks')
88        self.mempool_size = 0
89        assert_equal(node.getblockcount(), 200)
90        assert_equal(node.getmempoolinfo()['size'], self.mempool_size)
91
92        self.log.info("Check default settings")
93        # Settings are listed in BTC/kvB
94        assert_equal(node.getmempoolinfo()['minrelaytxfee'], Decimal(DEFAULT_MIN_RELAY_TX_FEE) / COIN)
95        assert_equal(node.getmempoolinfo()['incrementalrelayfee'], Decimal(DEFAULT_INCREMENTAL_RELAY_FEE) / COIN)
96
97        self.log.info('Should not accept garbage to testmempoolaccept')
98        assert_raises_rpc_error(-3, 'JSON value of type string is not of expected type array', lambda: node.testmempoolaccept(rawtxs='ff00baar'))
99        assert_raises_rpc_error(-8, 'Array must contain between 1 and 25 transactions.', lambda: node.testmempoolaccept(rawtxs=['ff22']*26))
100        assert_raises_rpc_error(-8, 'Array must contain between 1 and 25 transactions.', lambda: node.testmempoolaccept(rawtxs=[]))
101        assert_raises_rpc_error(-22, 'TX decode failed', lambda: node.testmempoolaccept(rawtxs=['ff00baar']))
102
103        self.log.info('A transaction already in the blockchain')
104        tx = self.wallet.create_self_transfer()['tx']  # Pick a random coin(base) to spend
105        tx.vout.append(deepcopy(tx.vout[0]))
106        tx.vout[0].nValue = int(0.3 * COIN)
107        tx.vout[1].nValue = int(49 * COIN)
108        raw_tx_in_block = tx.serialize().hex()
109        txid_in_block = self.wallet.sendrawtransaction(from_node=node, tx_hex=raw_tx_in_block)
110        self.generate(node, 1)
111        self.mempool_size = 0
112        # Also check feerate. 1BTC/kvB fails
113        assert_raises_rpc_error(-8, "Fee rates larger than or equal to 1BTC/kvB are not accepted", lambda: self.check_mempool_result(
114            result_expected=None,
115            rawtxs=[raw_tx_in_block],
116            maxfeerate=1,
117        ))
118        # Check negative feerate
119        assert_raises_rpc_error(-3, "Amount out of range", lambda: self.check_mempool_result(
120            result_expected=None,
121            rawtxs=[raw_tx_in_block],
122            maxfeerate=-0.01,
123        ))
124        # ... 0.99 passes
125        self.check_mempool_result(
126            result_expected=[{'txid': txid_in_block, 'allowed': False, 'reject-reason': 'txn-already-known'}],
127            rawtxs=[raw_tx_in_block],
128            maxfeerate=0.99,
129        )
130
131        self.log.info('A transaction not in the mempool')
132        fee = Decimal('0.000007')
133        utxo_to_spend = self.wallet.get_utxo(txid=txid_in_block)  # use 0.3 BTC UTXO
134        tx = self.wallet.create_self_transfer(utxo_to_spend=utxo_to_spend, sequence=MAX_BIP125_RBF_SEQUENCE)['tx']
135        tx.vout[0].nValue = int((Decimal('0.3') - fee) * COIN)
136        raw_tx_0 = tx.serialize().hex()
137        txid_0 = tx.txid_hex
138        self.check_mempool_result(
139            result_expected=[{'txid': txid_0, 'allowed': True, 'vsize_adjusted': tx.get_vsize(),  'vsize': tx.get_vsize(), 'vsize_bip141': tx.get_vsize(),'fees': {'base': fee}}],
140            rawtxs=[raw_tx_0],
141        )
142
143        self.log.info('A final transaction not in the mempool')
144        output_amount = Decimal('0.025')
145        tx = self.wallet.create_self_transfer(
146            sequence=SEQUENCE_FINAL,
147            locktime=node.getblockcount() + 2000,  # Can be anything
148        )['tx']
149        tx.vout[0].nValue = int(output_amount * COIN)
150        raw_tx_final = tx.serialize().hex()
151        tx = tx_from_hex(raw_tx_final)
152        fee_expected = Decimal('50.0') - output_amount
153        self.check_mempool_result(
154            result_expected=[{'txid': tx.txid_hex, 'allowed': True, 'vsize_adjusted': tx.get_vsize(), 'vsize': tx.get_vsize(), 'vsize_bip141': tx.get_vsize(), 'fees': {'base': fee_expected}}],
155            rawtxs=[tx.serialize().hex()],
156            maxfeerate=0,
157        )
158        node.sendrawtransaction(hexstring=raw_tx_final, maxfeerate=0)
159        self.mempool_size += 1
160
161        self.log.info('A transaction in the mempool')
162        node.sendrawtransaction(hexstring=raw_tx_0)
163        self.mempool_size += 1
164        self.check_mempool_result(
165            result_expected=[{'txid': txid_0, 'allowed': False, 'reject-reason': 'txn-already-in-mempool'}],
166            rawtxs=[raw_tx_0],
167        )
168
169        self.log.info('A transaction that replaces a mempool transaction')
170        tx = tx_from_hex(raw_tx_0)
171        tx.vout[0].nValue -= int(fee * COIN)  # Double the fee
172        raw_tx_0 = tx.serialize().hex()
173        txid_0 = tx.txid_hex
174        self.check_mempool_result(
175            result_expected=[{'txid': txid_0, 'allowed': True, 'vsize_adjusted': tx.get_vsize(), 'vsize': tx.get_vsize(), 'vsize_bip141': tx.get_vsize(), 'fees': {'base': (2 * fee)}}],
176            rawtxs=[raw_tx_0],
177        )
178        node.sendrawtransaction(hexstring=tx.serialize().hex(), maxfeerate=0)
179
180        self.log.info('A transaction with missing inputs, that never existed')
181        tx = tx_from_hex(raw_tx_0)
182        tx.vin[0].prevout = COutPoint(hash=int('ff' * 32, 16), n=14)
183        self.check_mempool_result(
184            result_expected=[{'txid': tx.txid_hex, 'allowed': False, 'reject-reason': 'missing-inputs'}],
185            rawtxs=[tx.serialize().hex()],
186        )
187
188        self.log.info('A transaction with missing inputs, that existed once in the past')
189        tx = tx_from_hex(raw_tx_0)
190        tx.vin[0].prevout.n = 1  # Set vout to 1, to spend the other outpoint (49 coins) of the in-chain-tx we want to double spend
191        raw_tx_1 = tx.serialize().hex()
192        txid_1 = node.sendrawtransaction(hexstring=raw_tx_1, maxfeerate=0)
193        # Now spend both to "clearly hide" the outputs, ie. remove the coins from the utxo set by spending them
194        tx = self.wallet.create_self_transfer()['tx']
195        tx.vin.append(deepcopy(tx.vin[0]))
196        tx.wit.vtxinwit.append(deepcopy(tx.wit.vtxinwit[0]))
197        tx.vin[0].prevout = COutPoint(hash=int(txid_0, 16), n=0)
198        tx.vin[1].prevout = COutPoint(hash=int(txid_1, 16), n=0)
199        tx.vout[0].nValue = int(0.1 * COIN)
200        raw_tx_spend_both = tx.serialize().hex()
201        txid_spend_both = self.wallet.sendrawtransaction(from_node=node, tx_hex=raw_tx_spend_both)
202        self.generate(node, 1)
203        self.mempool_size = 0
204        # Now see if we can add the coins back to the utxo set by sending the exact txs again
205        self.check_mempool_result(
206            result_expected=[{'txid': txid_0, 'allowed': False, 'reject-reason': 'missing-inputs'}],
207            rawtxs=[raw_tx_0],
208        )
209        self.check_mempool_result(
210            result_expected=[{'txid': txid_1, 'allowed': False, 'reject-reason': 'missing-inputs'}],
211            rawtxs=[raw_tx_1],
212        )
213
214        self.log.info('Create a "reference" tx for later use')
215        utxo_to_spend = self.wallet.get_utxo(txid=txid_spend_both)
216        tx = self.wallet.create_self_transfer(utxo_to_spend=utxo_to_spend, sequence=SEQUENCE_FINAL)['tx']
217        tx.vout[0].nValue = int(0.05 * COIN)
218        raw_tx_reference = tx.serialize().hex()
219        # Reference tx should be valid on itself
220        self.check_mempool_result(
221            result_expected=[{'txid': tx.txid_hex, 'allowed': True, 'vsize_adjusted': tx.get_vsize(), 'vsize': tx.get_vsize(), 'vsize_bip141': tx.get_vsize(), 'fees': { 'base': Decimal('0.1') - Decimal('0.05')}}],
222            rawtxs=[tx.serialize().hex()],
223            maxfeerate=0,
224        )
225
226        self.log.info('A transaction with no outputs')
227        tx = tx_from_hex(raw_tx_reference)
228        tx.vout = []
229        self.check_mempool_result(
230            result_expected=[{'txid': tx.txid_hex, 'allowed': False, 'reject-reason': 'bad-txns-vout-empty'}],
231            rawtxs=[tx.serialize().hex()],
232        )
233
234        self.log.info('A really large transaction')
235        tx = tx_from_hex(raw_tx_reference)
236        tx.vin = [tx.vin[0]] * math.ceil((MAX_BLOCK_WEIGHT // WITNESS_SCALE_FACTOR) / len(tx.vin[0].serialize()))
237        self.check_mempool_result(
238            result_expected=[{'txid': tx.txid_hex, 'allowed': False, 'reject-reason': 'bad-txns-oversize'}],
239            rawtxs=[tx.serialize().hex()],
240        )
241
242        self.log.info('A transaction with negative output value')
243        tx = tx_from_hex(raw_tx_reference)
244        tx.vout[0].nValue *= -1
245        self.check_mempool_result(
246            result_expected=[{'txid': tx.txid_hex, 'allowed': False, 'reject-reason': 'bad-txns-vout-negative'}],
247            rawtxs=[tx.serialize().hex()],
248        )
249
250        # The following two validations prevent overflow of the output amounts (see CVE-2010-5139).

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

Independent explanations by MyBitcoinExplorer. Not affiliated with or endorsed by Bitcoin Core. Guides are educational and do not replace the source or its tests.

Bitcoin Core source © its contributors, distributed under the MIT license. Original notices and bundled third-party licenses are retained in the source tree.