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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#include <chain.h>
6#include <chainparams.h>
7#include <pow.h>
8#include <primitives/block.h>
9#include <test/fuzz/FuzzedDataProvider.h>
10#include <test/fuzz/fuzz.h>
11#include <test/fuzz/util.h>
12#include <util/chaintype.h>
13#include <util/check.h>
14#include <util/overflow.h>
15
16#include <cstdint>
17#include <optional>
18#include <string>
19#include <vector>
20
21void initialize_pow()
22{
23    SelectParams(ChainType::MAIN);
24}
25
26FUZZ_TARGET(pow, .init = initialize_pow)
27{
28    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
29    const Consensus::Params& consensus_params = Params().GetConsensus();
30    std::vector<std::unique_ptr<CBlockIndex>> blocks;
31    const uint32_t fixed_time = fuzzed_data_provider.ConsumeIntegral<uint32_t>();
32    const uint32_t fixed_bits = fuzzed_data_provider.ConsumeIntegral<uint32_t>();
33    LIMITED_WHILE (fuzzed_data_provider.remaining_bytes() > 0, 10000) {
34        const std::optional<CBlockHeader> block_header = ConsumeDeserializable<CBlockHeader>(fuzzed_data_provider);
35        if (!block_header) {
36            continue;
37        }
38        CBlockIndex& current_block{
39            *blocks.emplace_back(std::make_unique<CBlockIndex>(*block_header))};
40        {
41            CBlockIndex* previous_block = blocks.empty() ? nullptr : PickValue(fuzzed_data_provider, blocks).get();
42            const int current_height = (previous_block != nullptr && previous_block->nHeight != std::numeric_limits<int>::max()) ? previous_block->nHeight + 1 : 0;
43            if (fuzzed_data_provider.ConsumeBool()) {
44                current_block.pprev = previous_block;
45            }
46            if (fuzzed_data_provider.ConsumeBool()) {
47                current_block.nHeight = current_height;
48            }
49            if (fuzzed_data_provider.ConsumeBool()) {
50                const uint32_t seconds = current_height * consensus_params.nPowTargetSpacing;
51                if (!AdditionOverflow(fixed_time, seconds)) {
52                    current_block.nTime = fixed_time + seconds;
53                }
54            }
55            if (fuzzed_data_provider.ConsumeBool()) {
56                current_block.nBits = fixed_bits;
57            }
58            if (fuzzed_data_provider.ConsumeBool()) {
59                current_block.nChainWork = previous_block != nullptr ? previous_block->nChainWork + GetBlockProof(*previous_block) : arith_uint256{0};
60            } else {
61                current_block.nChainWork = ConsumeArithUInt256(fuzzed_data_provider);
62            }
63        }
64        {
65            (void)GetBlockProof(current_block);
66            (void)CalculateNextWorkRequired(&current_block, fuzzed_data_provider.ConsumeIntegralInRange<int64_t>(0, std::numeric_limits<int64_t>::max()), consensus_params);
67            if (current_block.nHeight != std::numeric_limits<int>::max() && current_block.nHeight - (consensus_params.DifficultyAdjustmentInterval() - 1) >= 0) {
68                (void)GetNextWorkRequired(&current_block, &(*block_header), consensus_params);
69            }
70        }
71        {
72            const auto& to = PickValue(fuzzed_data_provider, blocks);
73            const auto& from = PickValue(fuzzed_data_provider, blocks);
74            const auto& tip = PickValue(fuzzed_data_provider, blocks);
75            try {
76                (void)GetBlockProofEquivalentTime(*to, *from, *tip, consensus_params);
77            } catch (const uint_error&) {
78            }
79        }
80        {
81            const std::optional<uint256> hash = ConsumeDeserializable<uint256>(fuzzed_data_provider);
82            if (hash) {
83                (void)CheckProofOfWorkImpl(*hash, fuzzed_data_provider.ConsumeIntegral<unsigned int>(), consensus_params);
84            }
85        }
86    }
87}
88
89
90FUZZ_TARGET(pow_transition, .init = initialize_pow)
91{
92    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
93    const Consensus::Params& consensus_params{Params().GetConsensus()};
94    std::vector<std::unique_ptr<CBlockIndex>> blocks;
95
96    const uint32_t old_time{fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
97    const uint32_t new_time{fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
98    const int32_t version{fuzzed_data_provider.ConsumeIntegral<int32_t>()};
99    uint32_t nbits{fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
100
101    const arith_uint256 pow_limit = UintToArith256(consensus_params.powLimit);
102    arith_uint256 old_target;
103    old_target.SetCompact(nbits);
104    if (old_target > pow_limit) {
105        nbits = pow_limit.GetCompact();
106    }
107    // Create one difficulty adjustment period worth of headers
108    for (int height = 0; height < consensus_params.DifficultyAdjustmentInterval(); ++height) {
109        CBlockHeader header;
110        header.nVersion = version;
111        header.nTime = old_time;
112        header.nBits = nbits;
113        if (height == consensus_params.DifficultyAdjustmentInterval() - 1) {
114            header.nTime = new_time;
115        }
116        auto current_block{std::make_unique<CBlockIndex>(header)};
117        current_block->pprev = blocks.empty() ? nullptr : blocks.back().get();
118        current_block->nHeight = height;
119        blocks.emplace_back(std::move(current_block));
120    }
121    auto last_block{blocks.back().get()};
122    unsigned int new_nbits{GetNextWorkRequired(last_block, nullptr, consensus_params)};
123    Assert(PermittedDifficultyTransition(consensus_params, last_block->nHeight + 1, last_block->nBits, new_nbits));
124}
125

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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