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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) 2024-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 <arith_uint256.h>
6#include <blockencodings.h>
7#include <net.h>
8#include <net_processing.h>
9#include <netmessagemaker.h>
10#include <node/peerman_args.h>
11#include <test/fuzz/FuzzedDataProvider.h>
12#include <test/fuzz/fuzz.h>
13#include <test/fuzz/util.h>
14#include <test/util/net.h>
15#include <test/util/script.h>
16#include <test/util/setup_common.h>
17#include <test/util/time.h>
18#include <uint256.h>
19#include <validation.h>
20
21namespace {
22constexpr uint32_t FUZZ_MAX_HEADERS_RESULTS{16};
23
24class HeadersSyncSetup : public TestingSetup
25{
26    std::vector<CNode*> m_connections;
27
28public:
29    HeadersSyncSetup(const ChainType chain_type, TestOpts opts) : TestingSetup(chain_type, opts)
30    {
31        PeerManager::Options peerman_opts;
32        node::ApplyArgsManOptions(*m_node.args, peerman_opts);
33        peerman_opts.max_headers_result = FUZZ_MAX_HEADERS_RESULTS;
34        // The peerman's rng is a global that is reused, so it will be reused
35        // and may cause non-determinism between runs. This may even influence
36        // the global RNG, because seeding may be done from the global one. For
37        // now, avoid it influencing the global RNG, and initialize it with a
38        // constant instead.
39        peerman_opts.deterministic_rng = true;
40        // No txs are relayed. Disable irrelevant and possibly
41        // non-deterministic code paths.
42        peerman_opts.ignore_incoming_txs = true;
43        m_node.peerman = PeerManager::make(*m_node.connman, *m_node.addrman,
44                                           m_node.banman.get(), *m_node.chainman,
45                                           *m_node.mempool, *m_node.warnings, peerman_opts);
46
47        CConnman::Options options;
48        options.m_msgproc = m_node.peerman.get();
49        m_node.connman->Init(options);
50    }
51
52    void ResetAndInitialize() EXCLUSIVE_LOCKS_REQUIRED(NetEventsInterface::g_msgproc_mutex);
53    void SendMessage(FuzzedDataProvider& fuzzed_data_provider, CSerializedNetMsg&& msg)
54        EXCLUSIVE_LOCKS_REQUIRED(NetEventsInterface::g_msgproc_mutex);
55};
56
57void HeadersSyncSetup::ResetAndInitialize()
58{
59    m_connections.clear();
60    auto& connman = static_cast<ConnmanTestMsg&>(*m_node.connman);
61    connman.StopNodes();
62
63    static NodeId id{0};
64    std::vector<ConnectionType> conn_types = {
65        ConnectionType::OUTBOUND_FULL_RELAY,
66        ConnectionType::BLOCK_RELAY,
67        ConnectionType::INBOUND
68    };
69
70    for (auto conn_type : conn_types) {
71        CAddress addr{};
72        m_connections.push_back(new CNode(id++, nullptr, addr, 0, 0, addr, "", conn_type, false, 0));
73        CNode& p2p_node = *m_connections.back();
74
75        connman.Handshake(
76            /*node=*/p2p_node,
77            /*successfully_connected=*/true,
78            /*remote_services=*/ServiceFlags(NODE_NETWORK | NODE_WITNESS),
79            /*local_services=*/ServiceFlags(NODE_NETWORK | NODE_WITNESS),
80            /*version=*/PROTOCOL_VERSION,
81            /*relay_txs=*/true);
82
83        connman.AddTestNode(p2p_node);
84    }
85}
86
87void HeadersSyncSetup::SendMessage(FuzzedDataProvider& fuzzed_data_provider, CSerializedNetMsg&& msg)
88{
89    auto& connman = static_cast<ConnmanTestMsg&>(*m_node.connman);
90    CNode& connection = *PickValue(fuzzed_data_provider, m_connections);
91
92    connman.FlushSendBuffer(connection);
93    (void)connman.ReceiveMsgFrom(connection, std::move(msg));
94    connection.fPauseSend = false;
95    try {
96        connman.ProcessMessagesOnce(connection);
97    } catch (const std::ios_base::failure&) {
98    }
99    m_node.peerman->SendMessages(connection);
100}
101
102CBlockHeader ConsumeHeader(FuzzedDataProvider& fuzzed_data_provider, const uint256& prev_hash, uint32_t prev_nbits)
103{
104    CBlockHeader header;
105    header.nNonce = 0;
106    // Either use the previous difficulty or let the fuzzer choose. The upper target in the
107    // range comes from the bits value of the genesis block, which is 0x1d00ffff. The lower
108    // target comes from the bits value of mainnet block 840000, which is 0x17034219.
109    // Calling lower_target.SetCompact(0x17034219) and upper_target.SetCompact(0x1d00ffff)
110    // should return the values below.
111    //
112    // RPC commands to verify:
113    // getblockheader 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
114    // getblockheader 0000000000000000000320283a032748cef8227873ff4872689bf23f1cda83a5
115    if (fuzzed_data_provider.ConsumeBool()) {
116        header.nBits = prev_nbits;
117    } else {
118        arith_uint256 lower_target = UintToArith256(uint256{"0000000000000000000342190000000000000000000000000000000000000000"});
119        arith_uint256 upper_target = UintToArith256(uint256{"00000000ffff0000000000000000000000000000000000000000000000000000"});
120        arith_uint256 target = ConsumeArithUInt256InRange(fuzzed_data_provider, lower_target, upper_target);
121        header.nBits = target.GetCompact();
122    }
123    header.nTime = TicksSinceEpoch<std::chrono::seconds>(ConsumeTime(fuzzed_data_provider));
124    header.hashPrevBlock = prev_hash;
125    header.nVersion = fuzzed_data_provider.ConsumeIntegral<int32_t>();
126    return header;
127}
128
129CBlock ConsumeBlock(FuzzedDataProvider& fuzzed_data_provider, const uint256& prev_hash, uint32_t prev_nbits)
130{
131    auto header = ConsumeHeader(fuzzed_data_provider, prev_hash, prev_nbits);
132    // In order to reach the headers acceptance logic, the block is
133    // constructed in a way that will pass the mutation checks.
134    CBlock block{header};
135    CMutableTransaction tx;
136    tx.vin.resize(1);
137    tx.vout.resize(1);
138    tx.vout[0].nValue = 0;
139    tx.vin[0].scriptSig.resize(2);
140    block.vtx.push_back(MakeTransactionRef(tx));
141    block.hashMerkleRoot = block.vtx[0]->GetHash().ToUint256();
142    return block;
143}
144
145// Global setup works for this test as state modification (specifically in the
146// block index) would indicate a bug.
147HeadersSyncSetup* g_testing_setup;
148
149void initialize()
150{
151    static auto setup{
152        MakeNoLogFileContext<HeadersSyncSetup>(ChainType::MAIN,
153                                               {
154                                                   .setup_validation_interface = false,
155                                               }),
156    };
157    g_testing_setup = setup.get();
158}
159} // namespace
160
161FUZZ_TARGET(p2p_headers_presync, .init = initialize)
162{
163    SeedRandomStateForTest(SeedRand::ZEROS);
164    FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
165    // The steady clock is currently only used for logging, so a constant
166    // time-point seems acceptable for now.
167    FakeSteadyClock steady_ctx{};
168
169    ChainstateManager& chainman = *g_testing_setup->m_node.chainman;
170    CBlockHeader base{chainman.GetParams().GenesisBlock()};
171    const FakeNodeClock clock{base.Time()};
172
173    LOCK(NetEventsInterface::g_msgproc_mutex);
174
175    g_testing_setup->ResetAndInitialize();
176
177    // The chain is just a single block, so this is equal to 1
178    size_t original_index_size{WITH_LOCK(cs_main, return chainman.m_blockman.m_block_index.size())};
179    arith_uint256 total_work{WITH_LOCK(cs_main, return chainman.m_best_header->nChainWork)};
180
181    std::vector<CBlockHeader> all_headers;
182
183    LIMITED_WHILE (fuzzed_data_provider.ConsumeBool(), 100) {
184        auto finalized_block = [&]() {
185            CBlock block = ConsumeBlock(fuzzed_data_provider, base.GetHash(), base.nBits);
186            FinalizeHeader(block, chainman);
187            return block;
188        };
189
190        // Send low-work headers, compact blocks, and blocks
191        CallOneOf(
192            fuzzed_data_provider,
193            [&]() NO_THREAD_SAFETY_ANALYSIS {
194                // Send FUZZ_MAX_HEADERS_RESULTS headers
195                std::vector<CBlock> headers;
196                headers.resize(FUZZ_MAX_HEADERS_RESULTS);
197                for (CBlock& header : headers) {
198                    header = ConsumeHeader(fuzzed_data_provider, base.GetHash(), base.nBits);
199                    FinalizeHeader(header, chainman);
200                    base = header;
201                }
202
203                all_headers.insert(all_headers.end(), headers.begin(), headers.end());
204
205                auto headers_msg = NetMsg::Make(NetMsgType::HEADERS, TX_WITH_WITNESS(headers));
206                g_testing_setup->SendMessage(fuzzed_data_provider, std::move(headers_msg));
207            },
208            [&]() NO_THREAD_SAFETY_ANALYSIS {
209                // Send a compact block
210                auto block = finalized_block();
211                CBlockHeaderAndShortTxIDs cmpct_block{block, fuzzed_data_provider.ConsumeIntegral<uint64_t>()};
212
213                all_headers.push_back(block);
214
215                auto headers_msg = NetMsg::Make(NetMsgType::CMPCTBLOCK, TX_WITH_WITNESS(cmpct_block));
216                g_testing_setup->SendMessage(fuzzed_data_provider, std::move(headers_msg));
217            },
218            [&]() NO_THREAD_SAFETY_ANALYSIS {
219                // Send a block
220                auto block = finalized_block();
221
222                all_headers.push_back(block);
223
224                auto headers_msg = NetMsg::Make(NetMsgType::BLOCK, TX_WITH_WITNESS(block));
225                g_testing_setup->SendMessage(fuzzed_data_provider, std::move(headers_msg));
226            });
227    }
228
229    // This is a conservative overestimate, as base is only moved forward when sending headers. In theory,
230    // the longest chain generated by this test is 1600 (FUZZ_MAX_HEADERS_RESULTS * 100) headers. In that case,
231    // this variable will accurately reflect the chain's total work.
232    total_work += CalculateClaimedHeadersWork(all_headers);
233
234    // This test should never create a chain with more work than MinimumChainWork.
235    assert(total_work < chainman.MinimumChainWork());
236
237    // The headers/blocks sent in this test should never be stored, as the chains don't have the work required
238    // to meet the anti-DoS work threshold. So, if at any point the block index grew in size, then there's a bug
239    // in the headers pre-sync logic.
240    assert(WITH_LOCK(cs_main, return chainman.m_blockman.m_block_index.size()) == original_index_size);
241}
242

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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