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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 <coins.h>
6#include <consensus/amount.h>
7#include <consensus/tx_check.h>
8#include <consensus/tx_verify.h>
9#include <consensus/validation.h>
10#include <kernel/chainstatemanager_opts.h>
11#include <kernel/cs_main.h>
12#include <policy/policy.h>
13#include <primitives/block.h>
14#include <primitives/transaction.h>
15#include <script/interpreter.h>
16#include <test/fuzz/FuzzedDataProvider.h>
17#include <test/fuzz/fuzz.h>
18#include <test/fuzz/util.h>
19#include <test/util/coins.h>
20#include <test/util/setup_common.h>
21#include <txdb.h>
22#include <util/hasher.h>
23#include <util/threadpool.h>
24
25#include <cassert>
26#include <algorithm>
27#include <cstdint>
28#include <functional>
29#include <limits>
30#include <memory>
31#include <optional>
32#include <ranges>
33#include <stdexcept>
34#include <string>
35#include <utility>
36#include <vector>
37
38namespace {
39/**
40 * MutationGuardCoinsViewCache asserts that nothing mutates cacheCoins until
41 * BatchWrite is called. It keeps a snapshot of the cacheCoins state, which it
42 * uses for the assertion in BatchWrite. After the call to the superclass
43 * CCoinsViewCache::BatchWrite returns, it recomputes the snapshot at that
44 * moment.
45 */
46class MutationGuardCoinsViewCache final : public CCoinsViewCache
47{
48private:
49    struct CacheCoinSnapshot {
50        COutPoint outpoint;
51        bool dirty{false};
52        bool fresh{false};
53        Coin coin;
54        bool operator==(const CacheCoinSnapshot&) const = default;
55    };
56
57    std::vector<CacheCoinSnapshot> ComputeCacheCoinsSnapshot() const
58    {
59        std::vector<CacheCoinSnapshot> snapshot;
60        snapshot.reserve(cacheCoins.size());
61
62        for (const auto& [outpoint, entry] : cacheCoins) {
63            snapshot.emplace_back(outpoint, entry.IsDirty(), entry.IsFresh(), entry.coin);
64        }
65
66        std::ranges::sort(snapshot, std::less<>{}, &CacheCoinSnapshot::outpoint);
67        return snapshot;
68    }
69
70    mutable std::vector<CacheCoinSnapshot> m_expected_snapshot{ComputeCacheCoinsSnapshot()};
71
72public:
73    void BatchWrite(CoinsViewCacheCursor& cursor, const uint256& block_hash) override
74    {
75        // Nothing must modify cacheCoins other than BatchWrite.
76        assert(ComputeCacheCoinsSnapshot() == m_expected_snapshot);
77        CCoinsViewCache::BatchWrite(cursor, block_hash);
78        m_expected_snapshot = ComputeCacheCoinsSnapshot();
79    }
80
81    using CCoinsViewCache::CCoinsViewCache;
82};
83
84// Reuse a single global thread pool across fuzz iterations. Creating and destroying a pool every
85// iteration leaks memory, since iterations can run faster than the OS can tear down the threads.
86std::shared_ptr<ThreadPool> g_thread_pool{std::make_shared<ThreadPool>("view_fuzz")};
87
88void StartPoolIfNeeded()
89{
90    if (!g_thread_pool->WorkersCount()) g_thread_pool->Start(DEFAULT_PREVOUTFETCH_THREADS);
91}
92
93//! Build a random block and seed a view with utxos for its inputs.
94CBlock BuildRandomBlock(FuzzedDataProvider& fuzzed_data_provider, CCoinsView& view)
95{
96    CBlock block;
97    CMutableTransaction coinbase;
98    coinbase.vin.emplace_back();
99    block.vtx.push_back(MakeTransactionRef(coinbase));
100
101    CCoinsViewCache seed_cache{&view, /*deterministic=*/true};
102    seed_cache.SetBestBlock(uint256::ONE);
103
104    Txid prevhash{Txid::FromUint256(ConsumeUInt256(fuzzed_data_provider))};
105    LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 100)
106    {
107        CMutableTransaction tx;
108        LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 100)
109        {
110            const Txid txid{fuzzed_data_provider.ConsumeBool()
111                                ? Txid::FromUint256(ConsumeUInt256(fuzzed_data_provider))
112                                : prevhash};
113            const COutPoint outpoint{txid, fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
114            if (auto coin{ConsumeDeserializable<Coin>(fuzzed_data_provider)}; coin && !coin->IsSpent()) {
115                seed_cache.AddCoin(outpoint, std::move(*coin), /*possible_overwrite=*/true);
116            }
117            tx.vin.emplace_back(outpoint);
118        }
119        prevhash = tx.GetHash();
120        block.vtx.push_back(MakeTransactionRef(tx));
121    }
122
123    seed_cache.Flush();
124    return block;
125}
126
127} // namespace
128
129void initialize_coins_view()
130{
131    static const auto testing_setup = MakeNoLogFileContext<>();
132}
133
134void TestCoinsView(FuzzedDataProvider& fuzzed_data_provider, CCoinsViewCache& coins_view_cache, CCoinsView* backend_coins_view)
135{
136    auto* const db{dynamic_cast<CCoinsViewDB*>(backend_coins_view)};
137    auto* const overlay{dynamic_cast<CoinsViewOverlay*>(&coins_view_cache)};
138    const bool is_db{db != nullptr};
139    bool good_data{true};
140    auto* original_backend{backend_coins_view};
141
142    if (is_db) coins_view_cache.SetBestBlock(uint256::ONE);
143    COutPoint random_out_point;
144    Coin random_coin;
145    CMutableTransaction random_mutable_transaction;
146    LIMITED_WHILE (good_data && fuzzed_data_provider.ConsumeBool(), 10'000) {
147        CallOneOf(
148            fuzzed_data_provider,
149            [&] {
150                if (random_coin.IsSpent()) {
151                    return;
152                }
153                COutPoint outpoint{random_out_point};
154                Coin coin{random_coin};
155                if (fuzzed_data_provider.ConsumeBool()) {
156                    // We can only skip the check if no unspent coin exists for this outpoint.
157                    const bool possible_overwrite{coins_view_cache.PeekCoin(outpoint) || fuzzed_data_provider.ConsumeBool()};
158                    coins_view_cache.AddCoin(outpoint, std::move(coin), possible_overwrite);
159                } else {
160                    coins_view_cache.EmplaceCoinInternalDANGER(outpoint, std::move(coin));
161                }
162            },
163            [&] {
164                if (overlay && !overlay->AllInputsConsumed()) return; // CoinsViewOverlay::Flush() must have all inputs consumed before being called
165                coins_view_cache.Flush(/*reallocate_cache=*/fuzzed_data_provider.ConsumeBool());
166            },
167            [&] {
168                if (overlay) return; // CoinsViewOverlay::Sync() is never called in production code
169                coins_view_cache.Sync();
170            },
171            [&] {
172                if (db) WITH_LOCK(::cs_main, (void)db->CompactFullAsync());
173            },
174            [&] {
175                uint256 best_block{ConsumeUInt256(fuzzed_data_provider)};
176                // `CCoinsViewDB::BatchWrite()` requires a non-null best block.
177                if (is_db && best_block.IsNull()) best_block = uint256::ONE;
178                coins_view_cache.SetBestBlock(best_block);
179            },
180            [&] {
181                (void)coins_view_cache.CreateResetGuard();
182                // Reset() clears the best block, so reseed db-backed caches.
183                if (is_db) {
184                    const uint256 best_block{ConsumeUInt256(fuzzed_data_provider)};
185                    if (best_block.IsNull()) {
186                        good_data = false;
187                        return;
188                    }
189                    coins_view_cache.SetBestBlock(best_block);
190                }
191            },
192            [&] {
193                Coin move_to;
194                (void)coins_view_cache.SpendCoin(random_out_point, fuzzed_data_provider.ConsumeBool() ? &move_to : nullptr);
195            },
196            [&] {
197                coins_view_cache.Uncache(random_out_point);
198            },
199            [&] {
200                if (overlay) return; // CoinsViewOverlay::SetBackend() is never called in production code
201                const bool use_original_backend{fuzzed_data_provider.ConsumeBool()};
202                if (use_original_backend && backend_coins_view != original_backend) {
203                    // FRESH flags valid against the empty backend may be invalid
204                    // against the original backend, so reset before restoring it.
205                    (void)coins_view_cache.CreateResetGuard();
206                    // Reset() clears the best block; db backends require a non-null hash.
207                    if (is_db) coins_view_cache.SetBestBlock(uint256::ONE);
208                }
209                backend_coins_view = use_original_backend ? original_backend : &CoinsViewEmpty::Get();
210                coins_view_cache.SetBackend(*backend_coins_view);
211            },
212            [&] {
213                const std::optional<COutPoint> opt_out_point = ConsumeDeserializable<COutPoint>(fuzzed_data_provider);
214                if (!opt_out_point) {
215                    good_data = false;
216                    return;
217                }
218                random_out_point = *opt_out_point;
219            },
220            [&] {
221                const std::optional<Coin> opt_coin = ConsumeDeserializable<Coin>(fuzzed_data_provider);
222                if (!opt_coin) {
223                    good_data = false;
224                    return;
225                }
226                random_coin = *opt_coin;
227            },
228            [&] {
229                const std::optional<CMutableTransaction> opt_mutable_transaction = ConsumeDeserializable<CMutableTransaction>(fuzzed_data_provider, TX_WITH_WITNESS);
230                if (!opt_mutable_transaction) {
231                    good_data = false;
232                    return;
233                }
234                random_mutable_transaction = *opt_mutable_transaction;
235            },
236            [&] {
237                CoinsCachePair sentinel{};
238                sentinel.second.SelfRef(sentinel);
239                size_t dirty_count{0};
240                CCoinsMapMemoryResource resource;
241                CCoinsMap coins_map{0, SaltedCoinsCacheHasher{/*deterministic=*/true}, CCoinsMap::key_equal{}, &resource};
242                LIMITED_WHILE (good_data && fuzzed_data_provider.ConsumeBool(), 10'000) {
243                    CCoinsCacheEntry coins_cache_entry;
244                    if (fuzzed_data_provider.ConsumeBool()) {
245                        coins_cache_entry.coin = random_coin;
246                    } else {
247                        const std::optional<Coin> opt_coin = ConsumeDeserializable<Coin>(fuzzed_data_provider);
248                        if (!opt_coin) {
249                            good_data = false;
250                            return;

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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