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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) 2019-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 <chainparams.h>
6#include <hash.h>
7#include <net.h>
8#include <netmessagemaker.h>
9#include <protocol.h>
10#include <test/fuzz/FuzzedDataProvider.h>
11#include <test/fuzz/fuzz.h>
12#include <test/fuzz/util.h>
13#include <util/chaintype.h>
14
15#include <algorithm>
16#include <cassert>
17#include <cstdint>
18#include <limits>
19#include <optional>
20#include <vector>
21
22namespace {
23
24auto g_all_messages = ALL_NET_MESSAGE_TYPES;
25
26void initialize_p2p_transport_serialization()
27{
28    static ECC_Context ecc_context{};
29    SelectParams(ChainType::REGTEST);
30    std::sort(g_all_messages.begin(), g_all_messages.end());
31}
32
33} // namespace
34
35FUZZ_TARGET(p2p_transport_serialization, .init = initialize_p2p_transport_serialization)
36{
37    // Construct transports for both sides, with dummy NodeIds.
38    V1Transport recv_transport{NodeId{0}};
39    V1Transport send_transport{NodeId{1}};
40
41    FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
42
43    auto checksum_assist = fuzzed_data_provider.ConsumeBool();
44    auto magic_bytes_assist = fuzzed_data_provider.ConsumeBool();
45    std::vector<uint8_t> mutable_msg_bytes;
46
47    auto header_bytes_remaining = CMessageHeader::HEADER_SIZE;
48    if (magic_bytes_assist) {
49        auto msg_start = Params().MessageStart();
50        for (size_t i = 0; i < CMessageHeader::MESSAGE_SIZE_SIZE; ++i) {
51            mutable_msg_bytes.push_back(msg_start[i]);
52        }
53        header_bytes_remaining -= CMessageHeader::MESSAGE_SIZE_SIZE;
54    }
55
56    if (checksum_assist) {
57        header_bytes_remaining -= CMessageHeader::CHECKSUM_SIZE;
58    }
59
60    auto header_random_bytes = fuzzed_data_provider.ConsumeBytes<uint8_t>(header_bytes_remaining);
61    mutable_msg_bytes.insert(mutable_msg_bytes.end(), header_random_bytes.begin(), header_random_bytes.end());
62    auto payload_bytes = fuzzed_data_provider.ConsumeRemainingBytes<uint8_t>();
63
64    if (checksum_assist && mutable_msg_bytes.size() == CMessageHeader::CHECKSUM_OFFSET) {
65        CHash256 hasher;
66        unsigned char hsh[32];
67        hasher.Write(payload_bytes);
68        hasher.Finalize(hsh);
69        for (size_t i = 0; i < CMessageHeader::CHECKSUM_SIZE; ++i) {
70           mutable_msg_bytes.push_back(hsh[i]);
71        }
72    }
73
74    mutable_msg_bytes.insert(mutable_msg_bytes.end(), payload_bytes.begin(), payload_bytes.end());
75    std::span<const uint8_t> msg_bytes{mutable_msg_bytes};
76    while (msg_bytes.size() > 0) {
77        if (!recv_transport.ReceivedBytes(msg_bytes)) {
78            break;
79        }
80        if (recv_transport.ReceivedMessageComplete()) {
81            const auto time{NodeClock::time_point::max()};
82            bool reject_message{false};
83            CNetMessage msg = recv_transport.GetReceivedMessage(time, reject_message);
84            assert(msg.m_type.size() <= CMessageHeader::MESSAGE_TYPE_SIZE);
85            assert(msg.m_raw_message_size <= mutable_msg_bytes.size());
86            assert(msg.m_raw_message_size == CMessageHeader::HEADER_SIZE + msg.m_message_size);
87            assert(msg.m_time == time);
88
89            auto msg2 = NetMsg::Make(msg.m_type, std::span{msg.m_recv});
90            bool queued = send_transport.SetMessageToSend(msg2);
91            assert(queued);
92            std::optional<bool> known_more;
93            while (true) {
94                const auto& [to_send, more, _msg_type] = send_transport.GetBytesToSend(false);
95                if (known_more) assert(!to_send.empty() == *known_more);
96                if (to_send.empty()) break;
97                send_transport.MarkBytesSent(to_send.size());
98                known_more = more;
99            }
100        }
101    }
102}
103
104namespace {
105
106template<RandomNumberGenerator R>
107void SimulationTest(Transport& initiator, Transport& responder, R& rng, FuzzedDataProvider& provider)
108{
109    // Simulation test with two Transport objects, which send messages to each other, with
110    // sending and receiving fragmented into multiple pieces that may be interleaved. It primarily
111    // verifies that the sending and receiving side are compatible with each other, plus a few
112    // sanity checks. It does not attempt to introduce errors in the communicated data.
113
114    // Put the transports in an array for by-index access.
115    const std::array<Transport*, 2> transports = {&initiator, &responder};
116
117    // Two vectors representing in-flight bytes. inflight[i] is from transport[i] to transport[!i].
118    std::array<std::vector<uint8_t>, 2> in_flight;
119
120    // Two queues with expected messages. expected[i] is expected to arrive in transport[!i].
121    std::array<std::deque<CSerializedNetMsg>, 2> expected;
122
123    // Vectors with bytes last returned by GetBytesToSend() on transport[i].
124    std::array<std::vector<uint8_t>, 2> to_send;
125
126    // Last returned 'more' values (if still relevant) by transport[i]->GetBytesToSend(), for
127    // both have_next_message false and true.
128    std::array<std::optional<bool>, 2> last_more, last_more_next;
129
130    // Whether more bytes to be sent are expected on transport[i], before and after
131    // SetMessageToSend().
132    std::array<std::optional<bool>, 2> expect_more, expect_more_next;
133
134    // Function to consume a message type.
135    auto msg_type_fn = [&]() {
136        uint8_t v = provider.ConsumeIntegral<uint8_t>();
137        if (v == 0xFF) {
138            // If v is 0xFF, construct a valid (but possibly unknown) message type from the fuzz
139            // data.
140            std::string ret;
141            while (ret.size() < CMessageHeader::MESSAGE_TYPE_SIZE) {
142                char c = provider.ConsumeIntegral<char>();
143                // Match the allowed characters in CMessageHeader::IsMessageTypeValid(). Any other
144                // character is interpreted as end.
145                if (c < ' ' || c > 0x7E) break;
146                ret += c;
147            }
148            return ret;
149        } else {
150            // Otherwise, use it as index into the list of known messages.
151            return g_all_messages[v % g_all_messages.size()];
152        }
153    };
154
155    // Function to construct a CSerializedNetMsg to send.
156    auto make_msg_fn = [&](bool first) {
157        CSerializedNetMsg msg;
158        if (first) {
159            // Always send a "version" message as first one.
160            msg.m_type = "version";
161        } else {
162            msg.m_type = msg_type_fn();
163        }
164        // Determine size of message to send (limited to 75 kB for performance reasons).
165        size_t size = provider.ConsumeIntegralInRange<uint32_t>(0, 75000);
166        // Get payload of message from RNG.
167        msg.data = rng.randbytes(size);
168        // Return.
169        return msg;
170    };
171
172    // The next message to be sent (initially version messages, but will be replaced once sent).
173    std::array<CSerializedNetMsg, 2> next_msg = {
174        make_msg_fn(/*first=*/true),
175        make_msg_fn(/*first=*/true)
176    };
177
178    // Wrapper around transport[i]->GetBytesToSend() that performs sanity checks.
179    auto bytes_to_send_fn = [&](int side) -> Transport::BytesToSend {
180        // Invoke GetBytesToSend twice (for have_next_message = {false, true}). This function does
181        // not modify state (it's const), and only the "more" return value should differ between
182        // the calls.
183        const auto& [bytes, more_nonext, msg_type] = transports[side]->GetBytesToSend(false);
184        const auto& [bytes_next, more_next, msg_type_next] = transports[side]->GetBytesToSend(true);
185        // Compare with expected more.
186        if (expect_more[side].has_value()) assert(!bytes.empty() == *expect_more[side]);
187        // Verify consistency between the two results.
188        assert(std::ranges::equal(bytes, bytes_next));
189        assert(msg_type == msg_type_next);
190        if (more_nonext) assert(more_next);
191        // Compare with previously reported output.
192        assert(to_send[side].size() <= bytes.size());
193        assert(std::ranges::equal(to_send[side], std::span{bytes}.first(to_send[side].size())));
194        to_send[side].resize(bytes.size());
195        std::copy(bytes.begin(), bytes.end(), to_send[side].begin());
196        // Remember 'more' results.
197        last_more[side] = {more_nonext};
198        last_more_next[side] = {more_next};
199        // Return.
200        return {bytes, more_nonext, msg_type};
201    };
202
203    // Function to make side send a new message.
204    auto new_msg_fn = [&](int side) {
205        // Don't do anything if there are too many unreceived messages already.
206        if (expected[side].size() >= 16) return;
207        // Try to send (a copy of) the message in next_msg[side].
208        CSerializedNetMsg msg = next_msg[side].Copy();
209        bool queued = transports[side]->SetMessageToSend(msg);
210        // Update expected more data.
211        expect_more[side] = expect_more_next[side];
212        expect_more_next[side] = std::nullopt;
213        // Verify consistency of GetBytesToSend after SetMessageToSend
214        bytes_to_send_fn(/*side=*/side);
215        if (queued) {
216            // Remember that this message is now expected by the receiver.
217            expected[side].emplace_back(std::move(next_msg[side]));
218            // Construct a new next message to send.
219            next_msg[side] = make_msg_fn(/*first=*/false);
220        }
221    };
222
223    // Function to make side send out bytes (if any).
224    auto send_fn = [&](int side, bool everything = false) {
225        const auto& [bytes, more, msg_type] = bytes_to_send_fn(/*side=*/side);
226        // Don't do anything if no bytes to send.
227        if (bytes.empty()) return false;
228        size_t send_now = everything ? bytes.size() : provider.ConsumeIntegralInRange<size_t>(0, bytes.size());
229        if (send_now == 0) return false;
230        // Add bytes to the in-flight queue, and mark those bytes as consumed.
231        in_flight[side].insert(in_flight[side].end(), bytes.begin(), bytes.begin() + send_now);
232        transports[side]->MarkBytesSent(send_now);
233        // If all to-be-sent bytes were sent, move last_more data to expect_more data.
234        if (send_now == bytes.size()) {
235            expect_more[side] = last_more[side];
236            expect_more_next[side] = last_more_next[side];
237        }
238        // Remove the bytes from the last reported to-be-sent vector.
239        assert(to_send[side].size() >= send_now);
240        to_send[side].erase(to_send[side].begin(), to_send[side].begin() + send_now);
241        // Verify that GetBytesToSend gives a result consistent with earlier.
242        bytes_to_send_fn(/*side=*/side);
243        // Return whether anything was sent.
244        return send_now > 0;
245    };
246
247    // Function to make !side receive bytes (if any).
248    auto recv_fn = [&](int side, bool everything = false) {
249        // Don't do anything if no bytes in flight.
250        if (in_flight[side].empty()) return false;

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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