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

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1#!/usr/bin/env python3
2# Copyright (c) 2015-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"""
6Templates for constructing various sorts of invalid transactions.
7
8These templates (or an iterator over all of them) can be reused in different
9contexts to test using a number of invalid transaction types.
10
11Hopefully this makes it easier to get coverage of a full variety of tx
12validation checks through different interfaces (AcceptBlock, AcceptToMemPool,
13etc.) without repeating ourselves.
14
15Invalid tx cases not covered here can be found by running:
16
17    $ diff \
18      <(grep -IREho "bad-txns[a-zA-Z-]+" src | sort -u) \
19      <(grep -IEho "bad-txns[a-zA-Z-]+" test/functional/data/invalid_txs.py | sort -u)
20
21"""
22import abc
23
24from typing import Optional
25from test_framework.messages import (
26    COutPoint,
27    CTransaction,
28    CTxIn,
29    CTxInWitness,
30    CTxOut,
31    MAX_MONEY,
32    SEQUENCE_FINAL,
33)
34from test_framework.blocktools import (
35    create_tx_with_script,
36    MAX_BLOCK_SIGOPS,
37    MAX_STANDARD_TX_SIGOPS,
38)
39from test_framework.script import (
40    OP_TRUE,
41    CScript,
42    OP_0,
43    OP_2DIV,
44    OP_2MUL,
45    OP_AND,
46    OP_CAT,
47    OP_CHECKSIG,
48    OP_DIV,
49    OP_INVERT,
50    OP_LEFT,
51    OP_LSHIFT,
52    OP_MOD,
53    OP_MUL,
54    OP_OR,
55    OP_RETURN,
56    OP_RIGHT,
57    OP_RSHIFT,
58    OP_SUBSTR,
59    OP_XOR,
60)
61from test_framework.util import assert_equal
62from test_framework.script_util import (
63    MIN_PADDING,
64    MIN_STANDARD_TX_NONWITNESS_SIZE,
65    script_to_p2sh_script,
66)
67basic_p2sh = script_to_p2sh_script(CScript([OP_0]))
68
69class BadTxTemplate:
70    """Allows simple construction of a certain kind of invalid tx. Base class to be subclassed."""
71    __metaclass__ = abc.ABCMeta
72
73    # The expected error code given by bitcoind upon submission of the tx.
74    reject_reason: Optional[str] = ""
75
76    # Only specified if it differs from mempool acceptance error.
77    block_reject_reason = ""
78
79    # Is this tx considered valid when included in a block, but not for acceptance into
80    # the mempool (i.e. does it violate policy but not consensus)?
81    valid_in_block = False
82
83    def __init__(self, *, spend_tx=None, spend_block=None):
84        self.spend_tx = spend_block.vtx[0] if spend_block else spend_tx
85        self.spend_avail = sum(o.nValue for o in self.spend_tx.vout)
86        self.valid_txin = CTxIn(COutPoint(self.spend_tx.txid_int, 0), b"", SEQUENCE_FINAL)
87
88    @abc.abstractmethod
89    def get_tx(self, *args, **kwargs):
90        """Return a CTransaction that is invalid per the subclass."""
91        pass
92
93
94class OutputMissing(BadTxTemplate):
95    reject_reason = "bad-txns-vout-empty"
96
97    def get_tx(self):
98        tx = CTransaction()
99        tx.vin.append(self.valid_txin)
100        return tx
101
102
103class InputMissing(BadTxTemplate):
104    reject_reason = "bad-txns-vin-empty"
105
106    # We use a blank transaction here to make sure
107    # it is interpreted as a non-witness transaction.
108    # Otherwise the transaction will fail the
109    # "surpufluous witness" check during deserialization
110    # rather than the input count check.
111    def get_tx(self):
112        tx = CTransaction()
113        return tx
114
115
116# The following check prevents exploit of lack of merkle
117# tree depth commitment (CVE-2017-12842)
118class SizeTooSmall(BadTxTemplate):
119    reject_reason = "tx-size-small"
120    valid_in_block = True
121
122    def get_tx(self):
123        tx = CTransaction()
124        tx.vin.append(self.valid_txin)
125        tx.vout.append(CTxOut(0, CScript([OP_RETURN] + ([OP_0] * (MIN_PADDING - 2)))))
126        assert_equal(len(tx.serialize_without_witness()), 64)
127        assert_equal(MIN_STANDARD_TX_NONWITNESS_SIZE - 1, 64)
128        return tx
129
130# reject a transaction that contains a witness
131# but doesn't spend a segwit output
132class ExtraWitness(BadTxTemplate):
133    reject_reason = "tx-size-small"
134    block_reject_reason = "block-script-verify-flag-failed (Witness provided for non-witness script)"
135
136    def get_tx(self):
137        tx = CTransaction()
138        tx.vin.append(self.valid_txin)
139        tx.vout.append(CTxOut(0, CScript()))
140        tx.wit.vtxinwit = [CTxInWitness()]
141        tx.wit.vtxinwit[0].scriptWitness.stack = [CScript([OP_TRUE])]
142        return tx
143
144
145class BadInputOutpointIndex(BadTxTemplate):
146    # Won't be rejected - nonexistent outpoint index is treated as an orphan since the coins
147    # database can't distinguish between spent outpoints and outpoints which never existed.
148    reject_reason = None
149    # But fails in block
150    block_reject_reason = "bad-txns-inputs-missingorspent"
151
152    def get_tx(self):
153        num_indices = len(self.spend_tx.vin)
154        bad_idx = num_indices + 100
155
156        tx = CTransaction()
157        tx.vin.append(CTxIn(COutPoint(self.spend_tx.txid_int, bad_idx), b"", SEQUENCE_FINAL))
158        tx.vout.append(CTxOut(0, basic_p2sh))
159        return tx
160
161
162class DuplicateInput(BadTxTemplate):
163    reject_reason = 'bad-txns-inputs-duplicate'
164
165    def get_tx(self):
166        tx = CTransaction()
167        tx.vin.append(self.valid_txin)
168        tx.vin.append(self.valid_txin)
169        tx.vout.append(CTxOut(1, basic_p2sh))
170        return tx
171
172
173class PrevoutNullInput(BadTxTemplate):
174    reject_reason = 'bad-txns-prevout-null'
175
176    def get_tx(self):
177        tx = CTransaction()
178        tx.vin.append(self.valid_txin)
179        tx.vin.append(CTxIn(COutPoint(hash=0, n=0xffffffff)))
180        tx.vout.append(CTxOut(1, basic_p2sh))
181        return tx
182
183
184class NonexistentInput(BadTxTemplate):
185    reject_reason = None  # Added as an orphan tx.
186    # But fails in block
187    block_reject_reason = "bad-txns-inputs-missingorspent"
188
189    def get_tx(self):
190        tx = CTransaction()
191        tx.vin.append(CTxIn(COutPoint(self.spend_tx.txid_int + 1, 0), b"", SEQUENCE_FINAL))
192        tx.vin.append(self.valid_txin)
193        tx.vout.append(CTxOut(1, basic_p2sh))
194        return tx
195
196
197class SpendTooMuch(BadTxTemplate):
198    reject_reason = 'bad-txns-in-belowout'
199
200    def get_tx(self):
201        return create_tx_with_script(
202            self.spend_tx, 0, output_script=basic_p2sh, amount=(self.spend_avail + 1))
203
204
205class CreateNegative(BadTxTemplate):
206    reject_reason = 'bad-txns-vout-negative'
207
208    def get_tx(self):
209        return create_tx_with_script(self.spend_tx, 0, amount=-1)
210
211
212class CreateTooLarge(BadTxTemplate):
213    reject_reason = 'bad-txns-vout-toolarge'
214
215    def get_tx(self):
216        return create_tx_with_script(self.spend_tx, 0, amount=MAX_MONEY + 1)
217
218
219class CreateSumTooLarge(BadTxTemplate):
220    reject_reason = 'bad-txns-txouttotal-toolarge'
221
222    def get_tx(self):
223        tx = create_tx_with_script(self.spend_tx, 0, amount=MAX_MONEY)
224        tx.vout = [tx.vout[0]] * 2
225        return tx
226
227
228class InvalidOPIFConstruction(BadTxTemplate):
229    reject_reason = "mempool-script-verify-flag-failed (Invalid OP_IF construction)"
230
231    def get_tx(self):
232        return create_tx_with_script(
233            self.spend_tx, 0, script_sig=b'\x68' * 35,
234            amount=(self.spend_avail // 2))
235
236
237class TooManySigopsPerBlock(BadTxTemplate):
238    reject_reason = "bad-txns-too-many-sigops"
239    block_reject_reason = "bad-blk-sigops, out-of-bounds SigOpCount"
240
241    def get_tx(self):
242        lotsa_checksigs = CScript([OP_CHECKSIG] * (MAX_BLOCK_SIGOPS))
243        return create_tx_with_script(
244            self.spend_tx, 0,
245            output_script=lotsa_checksigs,
246            amount=1)
247
248
249class TooManySigopsPerTransaction(BadTxTemplate):
250    reject_reason = "bad-txns-too-many-sigops"

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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