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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) 2019-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 that we reject low difficulty headers to prevent our block tree from filling up with useless bloat"""
6
7from test_framework.test_framework import BitcoinTestFramework
8
9from test_framework.p2p import (
10    P2PInterface,
11)
12
13from test_framework.messages import (
14    msg_headers,
15)
16
17from test_framework.blocktools import (
18    MAX_FUTURE_BLOCK_TIME,
19    NORMAL_GBT_REQUEST_PARAMS,
20    create_block,
21)
22
23from test_framework.util import assert_equal
24
25import re
26import time
27
28NODE1_BLOCKS_REQUIRED = 15
29NODE2_BLOCKS_REQUIRED = 2047
30
31
32class RejectLowDifficultyHeadersTest(BitcoinTestFramework):
33    def set_test_params(self):
34        self.rpc_timeout *= 4  # To avoid timeout when generating BLOCKS_TO_MINE
35        self.setup_clean_chain = True
36        self.num_nodes = 4
37        # Node0 has no required chainwork; node1 requires 15 blocks on top of the genesis block; node2 requires 2047
38        self.extra_args = [["-minimumchainwork=0x0", "-checkblockindex=0"], ["-minimumchainwork=0x1f", "-checkblockindex=0"], ["-minimumchainwork=0x1000", "-checkblockindex=0"], ["-minimumchainwork=0x1000", "-checkblockindex=0", "[email protected]"]]
39
40    def setup_network(self):
41        self.setup_nodes()
42        self.reconnect_all()
43        self.sync_all()
44
45    def disconnect_all(self):
46        self.disconnect_nodes(0, 1)
47        self.disconnect_nodes(0, 2)
48        self.disconnect_nodes(0, 3)
49
50    def reconnect_all(self):
51        self.connect_nodes(0, 1)
52        self.connect_nodes(0, 2)
53        self.connect_nodes(0, 3)
54
55    def mocktime_all(self, time):
56        for n in self.nodes:
57            n.setmocktime(time)
58
59    def test_chains_sync_when_long_enough(self):
60        self.log.info("Generate blocks on the node with no required chainwork, and verify nodes 1 and 2 have no new headers in their headers tree")
61        with (
62                self.nodes[1].assert_debug_log(expected_msgs=["[net] Ignoring low-work chain (height=14)"], timeout=2),
63                self.nodes[2].assert_debug_log(expected_msgs=["[net] Ignoring low-work chain (height=14)"], timeout=2),
64                self.nodes[3].assert_debug_log(expected_msgs=["Synchronizing blockheaders, height: 14"], timeout=2),
65        ):
66            self.generate(self.nodes[0], NODE1_BLOCKS_REQUIRED-1, sync_fun=self.no_op)
67
68        # Node3 should always allow headers due to noban permissions
69        self.log.info("Check that node3 will sync headers (due to noban permissions)")
70
71        def check_node3_chaintips(num_tips, tip_hash, height):
72            node3_chaintips = self.nodes[3].getchaintips()
73            assert_equal(len(node3_chaintips), num_tips)
74            assert {
75                'height': height,
76                'hash': tip_hash,
77                'branchlen': height,
78                'status': 'headers-only',
79            } in node3_chaintips
80
81        check_node3_chaintips(2, self.nodes[0].getbestblockhash(), NODE1_BLOCKS_REQUIRED-1)
82
83        for node in self.nodes[1:3]:
84            chaintips = node.getchaintips()
85            assert_equal(len(chaintips), 1)
86            assert {
87                'height': 0,
88                'hash': '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206',
89                'branchlen': 0,
90                'status': 'active',
91            } in chaintips
92
93        self.log.info("Generate more blocks to satisfy node1's minchainwork requirement, and verify node2 still has no new headers in headers tree")
94        with (
95                self.nodes[2].assert_debug_log(expected_msgs=["[net] Ignoring low-work chain (height=15)"], timeout=2),
96                self.nodes[3].assert_debug_log(expected_msgs=["Synchronizing blockheaders, height: 15"], timeout=2),
97        ):
98            self.generate(self.nodes[0], NODE1_BLOCKS_REQUIRED - self.nodes[0].getblockcount(), sync_fun=self.no_op)
99        self.sync_blocks(self.nodes[0:2]) # node3 will sync headers (noban permissions) but not blocks (due to minchainwork)
100
101        assert {
102            'height': 0,
103            'hash': '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206',
104            'branchlen': 0,
105            'status': 'active',
106        } in self.nodes[2].getchaintips()
107
108        assert_equal(len(self.nodes[2].getchaintips()), 1)
109
110        self.log.info("Check that node3 accepted these headers as well")
111        check_node3_chaintips(2, self.nodes[0].getbestblockhash(), NODE1_BLOCKS_REQUIRED)
112
113        self.log.info("Generate long chain for node0/node1/node3")
114        self.generate(self.nodes[0], NODE2_BLOCKS_REQUIRED-self.nodes[0].getblockcount(), sync_fun=self.no_op)
115
116        self.log.info("Verify that node2 and node3 will sync the chain when it gets long enough")
117        self.sync_blocks()
118
119    def test_peerinfo_includes_headers_presync_height(self):
120        self.log.info("Test that getpeerinfo() includes headers presync height")
121
122        # Disconnect network, so that we can find our own peer connection more
123        # easily
124        self.disconnect_all()
125
126        p2p = self.nodes[0].add_p2p_connection(P2PInterface())
127        node = self.nodes[0]
128
129        # Ensure we have a long chain already
130        current_height = self.nodes[0].getblockcount()
131        if (current_height < 3000):
132            self.generate(node, 3000-current_height, sync_fun=self.no_op)
133
134        # Send a group of 2000 headers, forking from genesis.
135        new_blocks = []
136        hashPrevBlock = int(node.getblockhash(0), 16)
137        for i in range(2000):
138            block = create_block(hashprev = hashPrevBlock, tmpl=node.getblocktemplate(NORMAL_GBT_REQUEST_PARAMS))
139            block.solve()
140            new_blocks.append(block)
141            hashPrevBlock = block.hash_int
142
143        headers_message = msg_headers(headers=new_blocks)
144        p2p.send_and_ping(headers_message)
145
146        # getpeerinfo should show a sync in progress
147        assert_equal(node.getpeerinfo()[0]['presynced_headers'], 2000)
148
149        self.log.info("Test whether a lagging clock aborts low-work headers sync")
150        node.disconnect_p2ps()
151        node.setmocktime(node.getblockheader(node.getblockhash(0))['mediantime'] - MAX_FUTURE_BLOCK_TIME - 1)
152        p2p = node.add_p2p_connection(P2PInterface())
153        p2p.send_without_ping(headers_message)
154        node.wait_until_stopped(expect_error=True, expected_ret_code=[-6,          # Unix
155                                                                      3,           # Windows native
156                                                                      0xC0000409], # Windows cross builds
157                                expected_stderr=re.compile("Failure when attempting to initiate headers sync: System clock"))
158
159    def test_large_reorgs_can_succeed(self):
160        self.log.info("Test that a 2000+ block reorg, starting from a point that is more than 2000 blocks before a locator entry, can succeed")
161
162        self.sync_all() # Ensure all nodes are synced.
163        self.disconnect_all()
164
165        # locator(block at height T) will have heights:
166        # [T, T-1, ..., T-10, T-12, T-16, T-24, T-40, T-72, T-136, T-264,
167        #  T-520, T-1032, T-2056, T-4104, ...]
168        # So mine a number of blocks > 4104 to ensure that the first window of
169        # received headers during a sync are fully between locator entries.
170        BLOCKS_TO_MINE = 4110
171
172        self.generate(self.nodes[0], BLOCKS_TO_MINE, sync_fun=self.no_op)
173        self.generate(self.nodes[1], BLOCKS_TO_MINE+2, sync_fun=self.no_op)
174
175        self.reconnect_all()
176
177        self.mocktime_all(int(time.time()))  # Temporarily hold time to avoid internal timeouts
178        self.sync_blocks(timeout=300) # Ensure tips eventually agree
179        self.mocktime_all(0)
180
181
182    def run_test(self):
183        self.test_chains_sync_when_long_enough()
184
185        self.test_large_reorgs_can_succeed()
186
187        self.test_peerinfo_includes_headers_presync_height()
188
189
190
191if __name__ == '__main__':
192    RejectLowDifficultyHeadersTest(__file__).main()
193

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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