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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// Copyright (c) 2020-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5
6#include <chain.h>
7#include <chainparams.h>
8#include <flatfile.h>
9#include <primitives/block.h>
10#include <primitives/transaction.h>
11#include <test/fuzz/FuzzedDataProvider.h>
12#include <test/fuzz/fuzz.h>
13#include <test/fuzz/util.h>
14#include <test/util/setup_common.h>
15#include <test/util/time.h>
16#include <test/util/validation.h>
17#include <validation.h>
18
19#include <ranges>
20#include <vector>
21
22const TestingSetup* g_setup;
23
24CBlockHeader ConsumeBlockHeader(FuzzedDataProvider& provider, uint256 prev_hash, int& nonce_counter)
25{
26    CBlockHeader header;
27    header.nVersion = provider.ConsumeIntegral<decltype(header.nVersion)>();
28    header.hashPrevBlock = prev_hash;
29    header.hashMerkleRoot = uint256{}; // never used
30    header.nTime = provider.ConsumeIntegral<decltype(header.nTime)>();
31    header.nBits = Params().GenesisBlock().nBits; // not fuzzed because not used (validation is mocked).
32    header.nNonce = nonce_counter++;              // prevent creating multiple block headers with the same hash
33    return header;
34}
35
36void initialize_block_index_tree()
37{
38    static const auto testing_setup = MakeNoLogFileContext<const TestingSetup>();
39    g_setup = testing_setup.get();
40}
41
42FUZZ_TARGET(block_index_tree, .init = initialize_block_index_tree)
43{
44    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
45    FakeNodeClock clock{ConsumeTime(fuzzed_data_provider)};
46    auto& chainman = static_cast<TestChainstateManager&>(*g_setup->m_node.chainman);
47    auto& blockman = static_cast<TestBlockManager&>(chainman.m_blockman);
48    CBlockIndex* genesis = chainman.ActiveChainstate().m_chain[0];
49    int nonce_counter = 0;
50    std::vector<CBlockIndex*> blocks;
51    blocks.push_back(genesis);
52    bool abort_run{false};
53
54    std::vector<CBlockIndex*> pruned_blocks;
55
56    LIMITED_WHILE (fuzzed_data_provider.ConsumeBool(), 1000) {
57        if (abort_run) break;
58        CallOneOf(
59            fuzzed_data_provider,
60            [&] {
61                // Receive a header building on an existing valid one. This assumes headers are valid, so PoW is not relevant here.
62                LOCK(cs_main);
63                CBlockIndex* prev_block = PickValue(fuzzed_data_provider, blocks);
64                if (!(prev_block->nStatus & BLOCK_FAILED_VALID)) {
65                    CBlockHeader header = ConsumeBlockHeader(fuzzed_data_provider, prev_block->GetBlockHash(), nonce_counter);
66                    CBlockIndex* index = blockman.AddToBlockIndex(header, chainman.m_best_header);
67                    assert(index->nStatus & BLOCK_VALID_TREE);
68                    assert(index->pprev == prev_block);
69                    blocks.push_back(index);
70                }
71            },
72            [&] {
73                // Receive a full block (valid or invalid) for an existing header, but don't attempt to connect it yet
74                LOCK(cs_main);
75                CBlockIndex* index = PickValue(fuzzed_data_provider, blocks);
76                // Must be new to us and not known to be invalid (e.g. because of an invalid ancestor).
77                if (index->nTx == 0 && !(index->nStatus & BLOCK_FAILED_VALID)) {
78                    if (fuzzed_data_provider.ConsumeBool()) { // Invalid
79                        BlockValidationState state;
80                        state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "consensus-invalid");
81                        chainman.InvalidBlockFound(index, state);
82                    } else {
83                        size_t nTx = fuzzed_data_provider.ConsumeIntegralInRange<size_t>(1, 1000);
84                        CBlock block; // Dummy block, so that ReceivedBlockTransactions can infer a nTx value.
85                        block.vtx = std::vector<CTransactionRef>(nTx);
86                        FlatFilePos pos(0, fuzzed_data_provider.ConsumeIntegralInRange<int>(1, 1000));
87                        chainman.ReceivedBlockTransactions(block, index, pos);
88                        assert(index->nStatus & BLOCK_VALID_TRANSACTIONS);
89                        assert(index->nStatus & BLOCK_HAVE_DATA);
90                    }
91                }
92            },
93            [&] {
94                // Simplified ActivateBestChain(): Try to move to a chain with more work - with the possibility of finding blocks to be invalid on the way
95                LOCK(cs_main);
96                auto& chain = chainman.ActiveChain();
97                CBlockIndex* old_tip = chain.Tip();
98                assert(old_tip);
99                do {
100                    CBlockIndex* best_tip = chainman.FindMostWorkChain();
101                    assert(best_tip);                   // Should at least return current tip
102                    if (best_tip == chain.Tip()) break; // Nothing to do
103                    // Rewind chain to forking point
104                    const CBlockIndex* fork = chain.FindFork(*best_tip);
105                    // If we can't go back to the fork point due to pruned data, abort this run. In reality, a pruned node would also currently just crash in this scenario.
106                    // This is very unlikely to happen due to the minimum pruning threshold of 550MiB.
107                    CBlockIndex* it = chain.Tip();
108                    while (it && it->nHeight != fork->nHeight) {
109                        if (!(it->nStatus & BLOCK_HAVE_UNDO)) {
110                            assert(blockman.m_have_pruned);
111                            abort_run = true;
112                            return;
113                        }
114                        it = it->pprev;
115                    }
116                    chain.SetTip(*chain[fork->nHeight]);
117
118                    // Prepare new blocks to connect
119                    std::vector<CBlockIndex*> to_connect;
120                    it = best_tip;
121                    while (it && it->nHeight != fork->nHeight) {
122                        to_connect.push_back(it);
123                        it = it->pprev;
124                    }
125                    // Connect blocks, possibly fail
126                    for (CBlockIndex* block : to_connect | std::views::reverse) {
127                        assert(!(block->nStatus & BLOCK_FAILED_VALID));
128                        assert(block->nStatus & BLOCK_HAVE_DATA);
129                        if (!block->IsValid(BLOCK_VALID_SCRIPTS)) {
130                            if (fuzzed_data_provider.ConsumeBool()) { // Invalid
131                                BlockValidationState state;
132                                state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "consensus-invalid");
133                                chainman.InvalidBlockFound(block, state);
134                                // This results in duplicate calls to InvalidChainFound, but mirrors the behavior in validation
135                                chainman.InvalidChainFound(to_connect.front());
136                                break;
137                            } else {
138                                block->RaiseValidity(BLOCK_VALID_SCRIPTS);
139                                block->nStatus |= BLOCK_HAVE_UNDO;
140                            }
141                        }
142                        chain.SetTip(*block);
143                        chainman.ActiveChainstate().PruneBlockIndexCandidates();
144                        // ActivateBestChainStep may release cs_main / not connect all blocks in one go - but only if we have at least as much chain work as we had at the start.
145                        if (block->nChainWork > old_tip->nChainWork && fuzzed_data_provider.ConsumeBool()) {
146                            break;
147                        }
148                    }
149                } while (node::CBlockIndexWorkComparator()(chain.Tip(), old_tip));
150                assert(chain.Tip()->nChainWork >= old_tip->nChainWork);
151            },
152            [&] {
153                // Prune chain - dealing with block files is beyond the scope of this test, so just prune random blocks, making no assumptions
154                // about what blocks are pruned together because they are in the same block file.
155                // Also don't prune blocks outside of the chain for now - this would make the fuzzer crash because of the problem described in
156                // https://github.com/bitcoin/bitcoin/issues/31512
157                LOCK(cs_main);
158                auto& chain = chainman.ActiveChain();
159                int prune_height = fuzzed_data_provider.ConsumeIntegralInRange<int>(0, chain.Height());
160                CBlockIndex* prune_block{chain[prune_height]};
161                if (prune_block != chain.Tip() && (prune_block->nStatus & BLOCK_HAVE_DATA)) {
162                    blockman.m_have_pruned = true;
163                    prune_block->nStatus &= ~BLOCK_HAVE_DATA;
164                    prune_block->nStatus &= ~BLOCK_HAVE_UNDO;
165                    prune_block->nFile = 0;
166                    prune_block->nDataPos = 0;
167                    prune_block->nUndoPos = 0;
168                    auto range = blockman.m_blocks_unlinked.equal_range(prune_block->pprev);
169                    while (range.first != range.second) {
170                        std::multimap<CBlockIndex*, CBlockIndex*>::iterator _it = range.first;
171                        range.first++;
172                        if (_it->second == prune_block) {
173                            blockman.m_blocks_unlinked.erase(_it);
174                        }
175                    }
176                    pruned_blocks.push_back(prune_block);
177                }
178            },
179            [&] {
180                // Download a previously pruned block
181                LOCK(cs_main);
182                size_t num_pruned = pruned_blocks.size();
183                if (num_pruned == 0) return;
184                size_t i = fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, num_pruned - 1);
185                CBlockIndex* index = pruned_blocks[i];
186                assert(!(index->nStatus & BLOCK_HAVE_DATA));
187                CBlock block;
188                block.vtx = std::vector<CTransactionRef>(index->nTx); // Set the number of tx to the prior value.
189                FlatFilePos pos(0, fuzzed_data_provider.ConsumeIntegralInRange<int>(1, 1000));
190                chainman.ReceivedBlockTransactions(block, index, pos);
191                assert(index->nStatus & BLOCK_VALID_TRANSACTIONS);
192                assert(index->nStatus & BLOCK_HAVE_DATA);
193                pruned_blocks.erase(pruned_blocks.begin() + i);
194            });
195    }
196    if (!abort_run) {
197        chainman.CheckBlockIndex();
198    }
199
200    // clean up global state changed by last iteration and prepare for next iteration
201    {
202        LOCK(cs_main);
203        genesis->nStatus |= BLOCK_HAVE_DATA;
204        genesis->nStatus |= BLOCK_HAVE_UNDO;
205        chainman.m_best_header = genesis;
206        chainman.ResetBestInvalid();
207        chainman.nBlockSequenceId = 2;
208        chainman.ActiveChain().SetTip(*genesis);
209        chainman.ActiveChainstate().setBlockIndexCandidates.clear();
210        chainman.m_cached_is_ibd = true;
211        blockman.m_blocks_unlinked.clear();
212        blockman.m_have_pruned = false;
213        blockman.CleanupForFuzzing();
214        // Delete all blocks but Genesis from block index
215        uint256 genesis_hash = genesis->GetBlockHash();
216        for (auto it = blockman.m_block_index.begin(); it != blockman.m_block_index.end();) {
217            if (it->first != genesis_hash) {
218                it = blockman.m_block_index.erase(it);
219            } else {
220                ++it;
221            }
222        }
223        chainman.ActiveChainstate().TryAddBlockIndexCandidate(genesis);
224        assert(blockman.m_block_index.size() == 1);
225        assert(chainman.ActiveChainstate().setBlockIndexCandidates.size() == 1);
226        assert(chainman.ActiveChain().Height() == 0);
227    }
228}
229

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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