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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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18,141 bytes · SHA-256 744c962b6d8b280c… · View upstream ↗

1// Copyright (c) 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 <dbwrapper.h>
6#include <compat/byteswap.h>
7#include <random.h>
8#include <sync.h>
9#include <test/fuzz/FuzzedDataProvider.h>
10#include <test/fuzz/fuzz.h>
11#include <test/fuzz/util.h>
12#include <test/util/random.h>
13#include <test/util/setup_common.h>
14#include <util/byte_units.h>
15#include <util/check.h>
16#include <util/threadpool.h>
17
18#include <leveldb/env.h>
19#include <leveldb/helpers/memenv/memenv.h>
20
21#include <algorithm>
22#include <cassert>
23#include <cstdint>
24#include <deque>
25#include <functional>
26#include <future>
27#include <latch>
28#include <map>
29#include <memory>
30#include <numeric>
31#include <optional>
32#include <set>
33#include <span>
34#include <string>
35#include <tuple>
36#include <vector>
37
38namespace {
39
40/**
41 * A leveldb::Env that wraps a memenv and captures scheduled background
42 * work (compaction) instead of dispatching to a real thread. The fuzz
43 * harness calls RunOne() or DrainWork() at fuzzer-chosen points to
44 * execute it, giving deterministic control over when compaction
45 * interleaves with foreground operations.
46 *
47 * Deadlock prevention: LevelDB's MakeRoomForWrite blocks on a condition
48 * variable when the previous immutable memtable is still awaiting compaction,
49 * or when the L0 file count hits kL0_StopWritesTrigger. Since both conditions
50 * can only be resolved by the (deferred) background work, the harness drains
51 * all pending work before every write to avoid a single-threaded deadlock.
52 * Callers must also DrainWork() before destroying the CDBWrapper, since the
53 * leveldb destructor waits for any pending background work to complete.
54 *
55 * The same reasoning rules out exercising DBOptions::force_compact under
56 * this env, because CompactRange(nullptr, nullptr) blocks waiting for
57 * background work that is queued on the (blocked) foreground thread. The
58 * sibling dbwrapper_threaded target covers that path.
59 */
60class DeterministicEnv final : public leveldb::EnvWrapper
61{
62    using WorkFunction = void (*)(void*);
63
64    struct Work {
65        WorkFunction function;
66        void* arg;
67    };
68
69    Mutex m_mutex;
70    std::deque<Work> m_queue GUARDED_BY(m_mutex);
71
72public:
73    explicit DeterministicEnv(leveldb::Env* base) : EnvWrapper(base) {}
74
75    void Schedule(WorkFunction function, void* arg) override EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
76    {
77        LOCK(m_mutex);
78        m_queue.push_back({function, arg});
79    }
80
81    /** Execute one pending background task. The task may schedule a
82     *  successor which is left pending for a later call. */
83    bool RunOne() EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
84    {
85        Work work;
86        {
87            LOCK(m_mutex);
88            if (m_queue.empty()) return false;
89            work = m_queue.front();
90            m_queue.pop_front();
91        }
92        work.function(work.arg);
93        return true;
94    }
95
96    /** Execute pending background tasks until none remain. */
97    void DrainWork() EXCLUSIVE_LOCKS_REQUIRED(!m_mutex) { while (RunOne()) {} }
98};
99
100constexpr size_t MAX_VALUE_LEN{4096};
101constexpr uint8_t MAX_VALUE_MULTIPLIER{8};
102constexpr size_t WRITE_BATCH_HEADER{12}; // See kHeader in db/write_batch.cc
103
104/** Mirror of CDBWrapper::OBFUSCATION_KEY, the fixed key under which leveldb
105 *  stores the obfuscation metadata entry when obfuscation is enabled. */
106const std::string OBFUSCATION_KEY{"\000obfuscate_key", 14};
107
108/** Generate a deterministic value from key and size. The fuzz input picks
109 *  a 16-bit length (up to MAX_VALUE_LEN) and an 8-bit multiplier so that a
110 *  small amount of fuzz input can produce a wide range of value sizes. */
111std::vector<uint8_t> MakeValue(uint16_t key, uint32_t size)
112{
113    std::vector<uint8_t> v(size);
114    std::iota(v.begin(), v.end(), static_cast<uint8_t>(key ^ (key >> 8)));
115    return v;
116}
117
118/** Equivalent to leveldb::BytewiseComparator() on 2-byte little-endian
119 *  serialized uint16_t keys, while keeping the oracle keyed by uint16_t. */
120struct LevelDBBytewiseU16Cmp {
121    bool operator()(uint16_t a, uint16_t b) const { return internal_bswap_16(a) < internal_bswap_16(b); }
122};
123
124/** key → value-size map ordered by LevelDB's bytewise comparator. */
125using Oracle = std::map<uint16_t, uint32_t, LevelDBBytewiseU16Cmp>;
126
127struct FailUnserialize {
128    template <typename Stream>
129    void Unserialize(Stream&) { throw std::ios_base::failure{"always fail"}; }
130};
131
132uint16_t ConsumeKey(FuzzedDataProvider& provider) { return provider.ConsumeIntegral<uint16_t>(); }
133uint32_t ConsumeValueSize(FuzzedDataProvider& provider)
134{
135    const uint16_t len{provider.ConsumeIntegralInRange<uint16_t>(0, MAX_VALUE_LEN)};
136    const uint8_t multiplier{provider.ConsumeIntegralInRange<uint8_t>(1, MAX_VALUE_MULTIPLIER)};
137    return static_cast<uint32_t>(len) * multiplier;
138}
139
140/** Verify that the DB iterator matches the oracle, handling the obfuscation
141 *  metadata entry (stored under a non-uint16_t key) when obfuscation is on. */
142void VerifyIterator(CDBWrapper& dbw, const Oracle& oracle,
143                    bool obfuscate, std::optional<uint16_t> seek_key = std::nullopt)
144{
145    const std::unique_ptr<CDBIterator> it{dbw.NewIterator()};
146    auto oracle_it{seek_key ? oracle.lower_bound(*seek_key) : oracle.begin()};
147    if (seek_key) {
148        it->Seek(*seek_key);
149    } else {
150        it->SeekToFirst();
151    }
152    for (; it->Valid(); it->Next()) {
153        uint16_t db_key;
154        assert(it->GetKey(db_key));
155        if (oracle_it != oracle.end() && db_key == oracle_it->first) {
156            std::vector<uint8_t> db_value;
157            assert(it->GetValue(db_value));
158            assert(db_value == MakeValue(db_key, oracle_it->second));
159            ++oracle_it;
160        } else {
161            assert(obfuscate);
162            std::string key_str;
163            assert(it->GetKey(key_str));
164            assert(key_str == OBFUSCATION_KEY);
165        }
166    }
167    assert(oracle_it == oracle.end());
168}
169
170/** Maximum number of concurrent reader threads in dbwrapper_concurrent_reads. */
171constexpr size_t MAX_READ_WORKERS{8};
172
173/** Maximum number of queries each worker executes in dbwrapper_concurrent_reads. */
174constexpr size_t MAX_READ_QUERIES_PER_WORKER{128};
175
176ThreadPool g_read_pool{"dbfuzz"};
177
178void StartReadPoolIfNeeded()
179{
180    if (!g_read_pool.WorkersCount()) g_read_pool.Start(MAX_READ_WORKERS);
181}
182
183/** Build randomized DBParams from the fuzz input, shared by all targets. */
184DBParams ConsumeDBParams(FuzzedDataProvider& provider, leveldb::Env* testing_env,
185                         bool obfuscate, DBOptions options = {})
186{
187    return DBParams{
188        .path = "dbwrapper_fuzz",
189        .cache_bytes = provider.ConsumeIntegralInRange<size_t>(64 << 10, 1_MiB),
190        .obfuscate = obfuscate,
191        .bloom_filter = provider.ConsumeBool(),
192        .options = options,
193        .testing_env = testing_env,
194        .max_file_size = provider.ConsumeBool()
195            ? DBWRAPPER_MAX_FILE_SIZE
196            : provider.ConsumeIntegralInRange<size_t>(1_MiB, 4_MiB),
197    };
198}
199
200template <typename DrainWorkFn, typename RunOneFn>
201void TestDbWrapper(FuzzedDataProvider& provider,
202                      leveldb::Env* testing_env,
203                      DrainWorkFn drain_work,
204                      RunOneFn run_one,
205                      bool allow_force_compact)
206{
207    SeedRandomStateForTest(SeedRand::ZEROS);
208
209    const bool obfuscate{provider.ConsumeBool()};
210
211    const auto make_db{[&](DBOptions options = {}) {
212        return std::make_unique<CDBWrapper>(ConsumeDBParams(provider, testing_env, obfuscate, options));
213    }};
214    std::unique_ptr<CDBWrapper> dbw{make_db()};
215
216    // Oracle: key → value size. Content is reconstructed via MakeValue().
217    Oracle oracle;
218
219    LIMITED_WHILE (provider.ConsumeBool(), 1'000) {
220        CallOneOf(
221            provider,
222            // --- Mutations ---
223            [&] {
224                const auto key{ConsumeKey(provider)};
225                const auto size{ConsumeValueSize(provider)};
226                drain_work();
227                dbw->Write(key, MakeValue(key, size), /*fSync=*/provider.ConsumeBool());
228                oracle[key] = size;
229            },
230            [&] {
231                const auto key{ConsumeKey(provider)};
232                drain_work();
233                dbw->Erase(key, /*fSync=*/provider.ConsumeBool());
234                oracle.erase(key);
235            },
236            [&] {
237                CDBBatch batch{*dbw};
238                std::map<uint16_t, uint32_t> batch_writes;
239                std::set<uint16_t> batch_erases;
240                const auto fill{[&] {
241                    LIMITED_WHILE (provider.ConsumeBool(), 20) {
242                        const auto key{ConsumeKey(provider)};
243                        if (provider.ConsumeBool()) {
244                            const auto size{ConsumeValueSize(provider)};
245                            batch.Write(key, MakeValue(key, size));
246                            batch_writes[key] = size;
247                            batch_erases.erase(key);
248                        } else {
249                            batch.Erase(key);
250                            batch_erases.insert(key);

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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