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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) 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 various fingerprinting protections.
6
7If a stale block more than a month old or its header are requested by a peer,
8the node should pretend that it does not have it to avoid fingerprinting.
9"""
10
11import time
12
13from test_framework.blocktools import create_block
14from test_framework.messages import CInv, MSG_BLOCK
15from test_framework.p2p import (
16    P2PInterface,
17    msg_headers,
18    msg_block,
19    msg_getdata,
20    msg_getheaders,
21    p2p_lock,
22)
23from test_framework.test_framework import BitcoinTestFramework
24from test_framework.util import (
25    assert_equal,
26)
27
28
29class P2PFingerprintTest(BitcoinTestFramework):
30    def set_test_params(self):
31        self.setup_clean_chain = True
32        self.num_nodes = 1
33
34    # Build a chain of blocks on top of given one
35    def build_chain(self, nblocks, prev_hash, prev_height, prev_median_time):
36        blocks = []
37        for _ in range(nblocks):
38            block = create_block(int(prev_hash, 16), height=prev_height + 1, ntime=prev_median_time + 1)
39            block.solve()
40
41            blocks.append(block)
42            prev_hash = block.hash_hex
43            prev_height += 1
44            prev_median_time += 1
45        return blocks
46
47    # Send a getdata request for a given block hash
48    def send_block_request(self, block_hash, node):
49        msg = msg_getdata()
50        msg.inv.append(CInv(MSG_BLOCK, block_hash))
51        node.send_without_ping(msg)
52
53    # Send a getheaders request for a given single block hash
54    def send_header_request(self, block_hash, node):
55        msg = msg_getheaders()
56        msg.hashstop = block_hash
57        node.send_without_ping(msg)
58
59    # Checks that stale blocks timestamped more than a month ago are not served
60    # by the node while recent stale blocks and old active chain blocks are.
61    # This does not currently test that stale blocks timestamped within the
62    # last month but that have over a month's worth of work are also withheld.
63    def run_test(self):
64        node0 = self.nodes[0].add_p2p_connection(P2PInterface())
65
66        # Set node time to 60 days ago
67        self.nodes[0].setmocktime(int(time.time()) - 60 * 24 * 60 * 60)
68
69        # Generating a chain of 10 blocks
70        block_hashes = self.generatetoaddress(self.nodes[0], 10, self.nodes[0].get_deterministic_priv_key().address)
71
72        # Create longer chain starting 2 blocks before current tip
73        height = len(block_hashes) - 2
74        block_hash = block_hashes[height - 1]
75        block_time = self.nodes[0].getblockheader(block_hash)["mediantime"] + 1
76        new_blocks = self.build_chain(5, block_hash, height, block_time)
77
78        # Force reorg to a longer chain
79        node0.send_without_ping(msg_headers(new_blocks))
80        node0.wait_for_getdata([x.hash_int for x in new_blocks])
81        for block in new_blocks:
82            node0.send_and_ping(msg_block(block))
83
84        # Check that reorg succeeded
85        assert_equal(self.nodes[0].getblockcount(), 13)
86
87        stale_hash = int(block_hashes[-1], 16)
88
89        # Check that getdata request for stale block succeeds
90        self.send_block_request(stale_hash, node0)
91        node0.wait_for_block(stale_hash, timeout=3)
92
93        # Check that getheader request for stale block header succeeds
94        self.send_header_request(stale_hash, node0)
95        node0.wait_for_header(hex(stale_hash), timeout=3)
96
97        # Longest chain is extended so stale is much older than chain tip
98        self.nodes[0].setmocktime(0)
99        block_hash = int(self.generatetoaddress(self.nodes[0], 1, self.nodes[0].get_deterministic_priv_key().address)[-1], 16)
100        assert_equal(self.nodes[0].getblockcount(), 14)
101        node0.wait_for_block(block_hash, timeout=3)
102
103        # Request for very old stale block should now fail
104        with p2p_lock:
105            node0.last_message.pop("block", None)
106        self.send_block_request(stale_hash, node0)
107        node0.sync_with_ping()
108        assert "block" not in node0.last_message
109
110        # Request for very old stale block header should now fail
111        with p2p_lock:
112            node0.last_message.pop("headers", None)
113        self.send_header_request(stale_hash, node0)
114        node0.sync_with_ping()
115        assert "headers" not in node0.last_message
116
117        # Verify we can fetch very old blocks and headers on the active chain
118        block_hash = int(block_hashes[2], 16)
119        self.send_block_request(block_hash, node0)
120        self.send_header_request(block_hash, node0)
121        node0.sync_with_ping()
122
123        self.send_block_request(block_hash, node0)
124        node0.wait_for_block(block_hash, timeout=3)
125
126        self.send_header_request(block_hash, node0)
127        node0.wait_for_header(hex(block_hash), timeout=3)
128
129
130if __name__ == '__main__':
131    P2PFingerprintTest(__file__).main()
132

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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