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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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1// Copyright (c) 2023-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 <crypto/sha256.h>
7#include <kernel/chainstatemanager_opts.h>
8#include <primitives/block.h>
9#include <primitives/transaction.h>
10#include <test/fuzz/FuzzedDataProvider.h>
11#include <test/fuzz/fuzz.h>
12#include <test/fuzz/util.h>
13#include <test/util/setup_common.h>
14#include <util/threadpool.h>
15
16#include <cassert>
17#include <cstdint>
18#include <memory>
19#include <optional>
20#include <vector>
21
22namespace {
23
24/** Number of distinct COutPoint values used in this test. */
25constexpr uint32_t NUM_OUTPOINTS = 256;
26/** Number of distinct Coin values used in this test (ignoring nHeight). */
27constexpr uint32_t NUM_COINS = 256;
28/** Maximum number CCoinsViewCache objects used in this test. */
29constexpr uint32_t MAX_CACHES = 4;
30/** Data type large enough to hold NUM_COINS-1. */
31using coinidx_type = uint8_t;
32
33struct PrecomputedData
34{
35    //! Randomly generated COutPoint values.
36    COutPoint outpoints[NUM_OUTPOINTS];
37
38    //! Randomly generated Coin values.
39    Coin coins[NUM_COINS];
40
41    //! Block with a tx containing as inputs the above outpoints.
42    CBlock block;
43
44    PrecomputedData()
45    {
46        static const uint8_t PREFIX_O[1] = {'o'}; /** Hash prefix for outpoint hashes. */
47        static const uint8_t PREFIX_S[1] = {'s'}; /** Hash prefix for coins scriptPubKeys. */
48        static const uint8_t PREFIX_M[1] = {'m'}; /** Hash prefix for coins nValue/fCoinBase. */
49
50        CMutableTransaction coinbase;
51        coinbase.vin.emplace_back();
52        block.vtx.push_back(MakeTransactionRef(coinbase));
53
54        CMutableTransaction tx;
55        for (uint32_t i = 0; i < NUM_OUTPOINTS; ++i) {
56            uint32_t idx = (i * 1200U) >> 12; /* Map 3 or 4 entries to same txid. */
57            const uint8_t ser[4] = {uint8_t(idx), uint8_t(idx >> 8), uint8_t(idx >> 16), uint8_t(idx >> 24)};
58            uint256 txid;
59            CSHA256().Write(PREFIX_O, 1).Write(ser, sizeof(ser)).Finalize(txid.begin());
60            outpoints[i].hash = Txid::FromUint256(txid);
61            outpoints[i].n = i;
62            tx.vin.emplace_back(outpoints[i]);
63        }
64        block.vtx.push_back(MakeTransactionRef(tx));
65
66        for (uint32_t i = 0; i < NUM_COINS; ++i) {
67            const uint8_t ser[4] = {uint8_t(i), uint8_t(i >> 8), uint8_t(i >> 16), uint8_t(i >> 24)};
68            uint256 hash;
69            CSHA256().Write(PREFIX_S, 1).Write(ser, sizeof(ser)).Finalize(hash.begin());
70            /* Convert hash to scriptPubkeys (of different lengths, so SanityCheck's cached memory
71             * usage check has a chance to detect mismatches). */
72            switch (i % 5U) {
73            case 0: /* P2PKH */
74                coins[i].out.scriptPubKey.resize(25);
75                coins[i].out.scriptPubKey[0] = OP_DUP;
76                coins[i].out.scriptPubKey[1] = OP_HASH160;
77                coins[i].out.scriptPubKey[2] = 20;
78                std::copy(hash.begin(), hash.begin() + 20, coins[i].out.scriptPubKey.begin() + 3);
79                coins[i].out.scriptPubKey[23] = OP_EQUALVERIFY;
80                coins[i].out.scriptPubKey[24] = OP_CHECKSIG;
81                break;
82            case 1: /* P2SH */
83                coins[i].out.scriptPubKey.resize(23);
84                coins[i].out.scriptPubKey[0] = OP_HASH160;
85                coins[i].out.scriptPubKey[1] = 20;
86                std::copy(hash.begin(), hash.begin() + 20, coins[i].out.scriptPubKey.begin() + 2);
87                coins[i].out.scriptPubKey[22] = OP_EQUAL;
88                break;
89            case 2: /* P2WPKH */
90                coins[i].out.scriptPubKey.resize(22);
91                coins[i].out.scriptPubKey[0] = OP_0;
92                coins[i].out.scriptPubKey[1] = 20;
93                std::copy(hash.begin(), hash.begin() + 20, coins[i].out.scriptPubKey.begin() + 2);
94                break;
95            case 3: /* P2WSH */
96                coins[i].out.scriptPubKey.resize(34);
97                coins[i].out.scriptPubKey[0] = OP_0;
98                coins[i].out.scriptPubKey[1] = 32;
99                std::copy(hash.begin(), hash.begin() + 32, coins[i].out.scriptPubKey.begin() + 2);
100                break;
101            case 4: /* P2TR */
102                coins[i].out.scriptPubKey.resize(34);
103                coins[i].out.scriptPubKey[0] = OP_1;
104                coins[i].out.scriptPubKey[1] = 32;
105                std::copy(hash.begin(), hash.begin() + 32, coins[i].out.scriptPubKey.begin() + 2);
106                break;
107            }
108            /* Hash again to construct nValue and fCoinBase. */
109            CSHA256().Write(PREFIX_M, 1).Write(ser, sizeof(ser)).Finalize(hash.begin());
110            coins[i].out.nValue = CAmount(hash.GetUint64(0) % MAX_MONEY);
111            coins[i].fCoinBase = (hash.GetUint64(1) & 7) == 0;
112            coins[i].nHeight = 0; /* Real nHeight used in simulation is set dynamically. */
113        }
114    }
115};
116
117enum class EntryType : uint8_t
118{
119    /* This entry in the cache does not exist (so we'd have to look in the parent cache). */
120    NONE,
121
122    /* This entry in the cache corresponds to an unspent coin. */
123    UNSPENT,
124
125    /* This entry in the cache corresponds to a spent coin. */
126    SPENT,
127};
128
129struct CacheEntry
130{
131    /* Type of entry. */
132    EntryType entrytype;
133
134    /* Index in the coins array this entry corresponds to (only if entrytype == UNSPENT). */
135    coinidx_type coinidx;
136
137    /* nHeight value for this entry (so the coins[coinidx].nHeight value is ignored; only if entrytype == UNSPENT). */
138    uint32_t height;
139};
140
141struct CacheLevel
142{
143    CacheEntry entry[NUM_OUTPOINTS];
144
145    void Wipe() {
146        for (uint32_t i = 0; i < NUM_OUTPOINTS; ++i) {
147            entry[i].entrytype = EntryType::NONE;
148        }
149    }
150};
151
152/** Class for the base of the hierarchy (roughly simulating a memory-backed CCoinsViewDB).
153 *
154 * The initial state consists of the empty UTXO set.
155 */
156class CoinsViewBottom final : public CoinsViewEmpty
157{
158    std::map<COutPoint, Coin> m_data;
159
160public:
161    std::optional<Coin> GetCoin(const COutPoint& outpoint) const final
162    {
163        if (auto it{m_data.find(outpoint)}; it != m_data.end()) {
164            assert(!it->second.IsSpent());
165            return it->second;
166        }
167        return std::nullopt;
168    }
169
170    void BatchWrite(CoinsViewCacheCursor& cursor, const uint256&) final
171    {
172        for (auto it{cursor.Begin()}; it != cursor.End(); it = cursor.NextAndMaybeErase(*it)) {
173            if (it->second.IsDirty()) {
174                if (it->second.coin.IsSpent()) {
175                    m_data.erase(it->first);
176                } else {
177                    if (cursor.WillErase(*it)) {
178                        m_data[it->first] = std::move(it->second.coin);
179                    } else {
180                        m_data[it->first] = it->second.coin;
181                    }
182                }
183            } else {
184                /* For non-dirty entries being written, compare them with what we have. */
185                auto it2 = m_data.find(it->first);
186                if (it->second.coin.IsSpent()) {
187                    assert(it2 == m_data.end());
188                } else {
189                    assert(it2 != m_data.end());
190                    assert(it->second.coin.out == it2->second.out);
191                    assert(it->second.coin.fCoinBase == it2->second.fCoinBase);
192                    assert(it->second.coin.nHeight == it2->second.nHeight);
193                }
194            }
195        }
196    }
197};
198
199// Hold a non-movable ResetGuard on the heap so StartFetching can remain active
200// for the lifetime of a CoinsViewOverlay cache level.
201struct OverlayFetchScope
202{
203    CCoinsViewCache::ResetGuard guard;
204    OverlayFetchScope(CoinsViewOverlay& view, const CBlock& block) : guard(view.StartFetching(block)) {}
205};
206
207// Reuse a single global thread pool across fuzz iterations. Creating and destroying a pool every
208// iteration leaks memory, since iterations can run faster than the OS can tear down the threads.
209std::shared_ptr<ThreadPool> g_thread_pool{std::make_shared<ThreadPool>("cache_fuzz")};
210
211void StartPoolIfNeeded()
212{
213    if (!g_thread_pool->WorkersCount()) g_thread_pool->Start(DEFAULT_PREVOUTFETCH_THREADS);
214}
215
216} // namespace
217
218FUZZ_TARGET(coinscache_sim, .init = [] { static auto setup{MakeNoLogFileContext<>()}; })
219{
220    SeedRandomStateForTest(SeedRand::ZEROS);
221    StartPoolIfNeeded();
222    /** Precomputed COutPoint and CCoins values. */
223    static const PrecomputedData data;
224
225    /** Dummy coinsview instance (base of the hierarchy). */
226    CoinsViewBottom bottom;
227    /** Real CCoinsViewCache objects. */
228    std::vector<std::unique_ptr<CCoinsViewCache>> caches;
229    /** Long-lived StartFetching guards, parallel to `caches` (entries are nullptr unless corresponding level is a CoinsViewOverlay). */
230    std::vector<std::unique_ptr<OverlayFetchScope>> fetch_scopes;
231    /** Simulated cache data (sim_caches[0] matches bottom, sim_caches[i+1] matches caches[i]). */
232    CacheLevel sim_caches[MAX_CACHES + 1];
233    /** Current height in the simulation. */
234    uint32_t current_height = 1U;
235
236    // Initialize bottom simulated cache.
237    sim_caches[0].Wipe();
238
239    /** Helper lookup function in the simulated cache stack. */
240    auto lookup = [&](uint32_t outpointidx, int sim_idx = -1) -> std::optional<std::pair<coinidx_type, uint32_t>> {
241        uint32_t cache_idx = sim_idx == -1 ? caches.size() : sim_idx;
242        while (true) {
243            const auto& entry = sim_caches[cache_idx].entry[outpointidx];
244            if (entry.entrytype == EntryType::UNSPENT) {
245                return {{entry.coinidx, entry.height}};
246            } else if (entry.entrytype == EntryType::SPENT) {
247                return std::nullopt;
248            };
249            if (cache_idx == 0) break;
250            --cache_idx;

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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