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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.

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1#!/usr/bin/env python3
2# Copyright (c) 2022-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
6import random
7import time
8from enum import Enum
9
10from test_framework.messages import MAGIC_BYTES
11from test_framework.p2p import P2PInterface
12from test_framework.test_framework import BitcoinTestFramework
13from test_framework.util import random_bitflip
14from test_framework.v2_p2p import (
15    EncryptedP2PState,
16    MAX_GARBAGE_LEN,
17)
18
19
20class TestType(Enum):
21    """ Scenarios to be tested:
22
23    1. EARLY_KEY_RESPONSE - The responder needs to wait until one byte is received which does not match the 16 bytes
24    consisting of network magic followed by "version\x00\x00\x00\x00\x00" before sending out its ellswift + garbage bytes
25    2. EXCESS_GARBAGE - Disconnection happens when > MAX_GARBAGE_LEN bytes garbage is sent
26    3. WRONG_GARBAGE_TERMINATOR - Disconnection happens when incorrect garbage terminator is sent
27    4. WRONG_GARBAGE - Disconnection happens when garbage bytes that is sent is different from what the peer receives
28    5. SEND_NO_AAD - Disconnection happens when AAD of first encrypted packet after the garbage terminator is not filled
29    6. SEND_NON_EMPTY_VERSION_PACKET - non-empty version packet is simply ignored
30    """
31    EARLY_KEY_RESPONSE = 0
32    EXCESS_GARBAGE = 1
33    WRONG_GARBAGE_TERMINATOR = 2
34    WRONG_GARBAGE = 3
35    SEND_NO_AAD = 4
36    SEND_NON_EMPTY_VERSION_PACKET = 5
37
38
39class EarlyKeyResponseState(EncryptedP2PState):
40    """ Modify v2 P2P protocol functions for testing EARLY_KEY_RESPONSE scenario"""
41    def __init__(self, initiating, net):
42        super().__init__(initiating=initiating, net=net)
43        self.can_data_be_received = False  # variable used to assert if data is received on recvbuf.
44
45    def initiate_v2_handshake(self):
46        """Send ellswift and garbage bytes in 2 parts when TestType = (EARLY_KEY_RESPONSE)"""
47        self.generate_keypair_and_garbage()
48        return b""
49
50
51class ExcessGarbageState(EncryptedP2PState):
52    """Generate > MAX_GARBAGE_LEN garbage bytes"""
53    def generate_keypair_and_garbage(self):
54        garbage_len = MAX_GARBAGE_LEN + random.randrange(1, MAX_GARBAGE_LEN + 1)
55        return super().generate_keypair_and_garbage(garbage_len)
56
57
58class WrongGarbageTerminatorState(EncryptedP2PState):
59    """Add option for sending wrong garbage terminator"""
60    def generate_keypair_and_garbage(self):
61        garbage_len = random.randrange(MAX_GARBAGE_LEN//2)
62        return super().generate_keypair_and_garbage(garbage_len)
63
64    def complete_handshake(self, response):
65        length, handshake_bytes = super().complete_handshake(response)
66        # first 16 bytes returned by complete_handshake() is the garbage terminator
67        wrong_garbage_terminator = random_bitflip(handshake_bytes[:16])
68        return length, wrong_garbage_terminator + handshake_bytes[16:]
69
70
71class WrongGarbageState(EncryptedP2PState):
72    """Generate tampered garbage bytes"""
73    def generate_keypair_and_garbage(self):
74        garbage_len = random.randrange(1, MAX_GARBAGE_LEN)
75        ellswift_garbage_bytes = super().generate_keypair_and_garbage(garbage_len)
76        # assume that garbage bytes sent to TestNode were tampered with
77        return ellswift_garbage_bytes[:64] + random_bitflip(ellswift_garbage_bytes[64:])
78
79
80class NoAADState(EncryptedP2PState):
81    """Add option for not filling first encrypted packet after garbage terminator with AAD"""
82    def generate_keypair_and_garbage(self):
83        garbage_len = random.randrange(1, MAX_GARBAGE_LEN)
84        return super().generate_keypair_and_garbage(garbage_len)
85
86    def complete_handshake(self, response):
87        self.sent_garbage = b''  # do not authenticate the garbage which is sent
88        return super().complete_handshake(response)
89
90
91class NonEmptyVersionPacketState(EncryptedP2PState):
92    """"Add option for sending non-empty transport version packet."""
93    def complete_handshake(self, response):
94        self.transport_version = random.randbytes(5)
95        return super().complete_handshake(response)
96
97
98class MisbehavingV2Peer(P2PInterface):
99    """Custom implementation of P2PInterface which uses modified v2 P2P protocol functions for testing purposes."""
100    def __init__(self, test_type):
101        super().__init__()
102        self.test_type = test_type
103
104    def connection_made(self, transport):
105        if self.test_type == TestType.EARLY_KEY_RESPONSE:
106            self.v2_state = EarlyKeyResponseState(initiating=True, net='regtest')
107        elif self.test_type == TestType.EXCESS_GARBAGE:
108            self.v2_state = ExcessGarbageState(initiating=True, net='regtest')
109        elif self.test_type == TestType.WRONG_GARBAGE_TERMINATOR:
110            self.v2_state = WrongGarbageTerminatorState(initiating=True, net='regtest')
111        elif self.test_type == TestType.WRONG_GARBAGE:
112            self.v2_state = WrongGarbageState(initiating=True, net='regtest')
113        elif self.test_type == TestType.SEND_NO_AAD:
114            self.v2_state = NoAADState(initiating=True, net='regtest')
115        elif TestType.SEND_NON_EMPTY_VERSION_PACKET:
116            self.v2_state = NonEmptyVersionPacketState(initiating=True, net='regtest')
117        super().connection_made(transport)
118
119    def data_received(self, t):
120        if self.test_type == TestType.EARLY_KEY_RESPONSE:
121            # check that data can be received on recvbuf only when mismatch from V1_PREFIX happens
122            assert self.v2_state.can_data_be_received
123        else:
124            super().data_received(t)
125
126
127class EncryptedP2PMisbehaving(BitcoinTestFramework):
128    def set_test_params(self):
129        self.num_nodes = 1
130        self.extra_args = [["-v2transport=1", "-peertimeout=3"]]
131
132    def run_test(self):
133        self.test_earlykeyresponse()
134        self.test_v2disconnection()
135
136    def test_earlykeyresponse(self):
137        self.log.info('Sending ellswift bytes in parts to ensure that response from responder is received only when')
138        self.log.info('ellswift bytes have a mismatch from the 16 bytes(network magic followed by "version\\x00\\x00\\x00\\x00\\x00")')
139        node0 = self.nodes[0]
140        node0.setmocktime(int(time.time()))
141        self.log.info('Sending first 4 bytes of ellswift which match network magic')
142        self.log.info('If a response is received, assertion failure would happen in our custom data_received() function')
143        with node0.wait_for_new_peer():
144            peer1 = node0.add_p2p_connection(MisbehavingV2Peer(TestType.EARLY_KEY_RESPONSE), wait_for_verack=False, send_version=False, supports_v2_p2p=True, wait_for_v2_handshake=False)
145        peer1.send_raw_message(MAGIC_BYTES['regtest'])
146        self.log.info('Sending remaining ellswift and garbage which are different from V1_PREFIX. Since a response is')
147        self.log.info('expected now, our custom data_received() function wouldn\'t result in assertion failure')
148        peer1.v2_state.can_data_be_received = True
149        self.wait_until(lambda: peer1.v2_state.ellswift_ours)
150        peer1.send_raw_message(peer1.v2_state.ellswift_ours[4:] + peer1.v2_state.sent_garbage)
151        # Ensure that the bytes sent after 4 bytes network magic are actually received.
152        self.wait_until(lambda: node0.getpeerinfo()[-1]["bytesrecv"] > 4)
153        self.wait_until(lambda: node0.getpeerinfo()[-1]["bytessent"] > 0)
154        with node0.assert_debug_log(['V2 handshake timeout, disconnecting peer=0']):
155            node0.bumpmocktime(4)  # `InactivityCheck()` triggers now
156            peer1.wait_for_disconnect(timeout=1)
157        self.log.info('successful disconnection since modified ellswift was sent as response')
158
159    def test_v2disconnection(self):
160        # test v2 disconnection scenarios
161        node0 = self.nodes[0]
162        expected_debug_message = [
163            [],  # EARLY_KEY_RESPONSE
164            ["V2 transport error: missing garbage terminator"],  # EXCESS_GARBAGE
165            ["V2 handshake timeout, disconnecting peer"],  # WRONG_GARBAGE_TERMINATOR
166            ["V2 transport error: packet decryption failure"],  # WRONG_GARBAGE
167            ["V2 transport error: packet decryption failure"],  # SEND_NO_AAD
168            [],  # SEND_NON_EMPTY_VERSION_PACKET
169        ]
170        for test_type in TestType:
171            if test_type == TestType.EARLY_KEY_RESPONSE:
172                continue
173            elif test_type == TestType.SEND_NON_EMPTY_VERSION_PACKET:
174                node0.add_p2p_connection(MisbehavingV2Peer(test_type), wait_for_verack=True, send_version=True, supports_v2_p2p=True)
175                self.log.info(f"No disconnection for {test_type.name}")
176            else:
177                with node0.assert_debug_log(expected_debug_message[test_type.value], timeout=5):
178                    node0.setmocktime(int(time.time()))
179                    peer1 = node0.add_p2p_connection(MisbehavingV2Peer(test_type), wait_for_verack=False, send_version=False, supports_v2_p2p=True, expect_success=False)
180                    # Make a passing connection for more robust disconnection checking.
181                    peer2 = node0.add_p2p_connection(P2PInterface())
182                    assert peer2.is_connected
183                    node0.bumpmocktime(4)  # `InactivityCheck()` triggers now
184                    peer1.wait_for_disconnect()
185                self.log.info(f"Expected disconnection for {test_type.name}")
186
187
188if __name__ == '__main__':
189    EncryptedP2PMisbehaving(__file__).main()
190

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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