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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) 2025-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 <consensus/tx_check.h>
6#include <consensus/validation.h>
7#include <net.h>
8#include <primitives/transaction.h>
9#include <private_broadcast.h>
10#include <test/fuzz/FuzzedDataProvider.h>
11#include <test/fuzz/fuzz.h>
12#include <test/fuzz/util.h>
13#include <test/fuzz/util/net.h>
14#include <test/util/setup_common.h>
15#include <test/util/time.h>
16#include <util/overflow.h>
17#include <util/time.h>
18
19#include <algorithm>
20#include <ranges>
21#include <unordered_map>
22#include <unordered_set>
23
24struct CTransactionRefHash {
25    size_t operator()(const CTransactionRef& tx) const
26    {
27        return static_cast<size_t>(tx->GetWitnessHash().ToUint256().GetUint64(0));
28    }
29};
30
31struct CTransactionRefComp {
32    bool operator()(const CTransactionRef& a, const CTransactionRef& b) const
33    {
34        return a->GetWitnessHash() == b->GetWitnessHash();
35    }
36};
37
38FUZZ_TARGET(private_broadcast)
39{
40    FuzzedDataProvider fdp(buffer.data(), buffer.size());
41    FakeNodeClock clock_ctx{ConsumeTime(fdp)};
42
43    const size_t cap{fdp.ConsumeIntegralInRange<size_t>(1, 12)};
44    const size_t max_send_attempts{fdp.ConsumeIntegralInRange<size_t>(1, 12)};
45    PrivateBroadcast pb{cap, max_send_attempts};
46
47    // Random transactions that the test generated and passed to Add(). Trimmed by Remove() and Add() cleanup.
48    // The values are the number of times a transaction was picked for sending.
49    std::unordered_map<CTransactionRef, size_t, CTransactionRefHash, CTransactionRefComp> transactions;
50    // The values are the number of times a transaction is planned to be sent.
51    std::unordered_map<CTransactionRef, size_t, CTransactionRefHash, CTransactionRefComp> planned_sends;
52    std::unordered_set<CTransactionRef, CTransactionRefHash, CTransactionRefComp> resolved_transactions;
53
54    // Transactions passed to PickTxForSend(), indexed by node id. Trimmed when
55    // Remove() is called or a transaction is reset or cleaned up by Add().
56    std::unordered_map<NodeId, CTransactionRef> nodes_sent_to;
57    std::unordered_set<NodeId> disconnected_nodes;
58
59    NodeId next_nodeid{0}; // Generate unique node ids.
60
61    const auto is_pending{[&](const auto& entry) {
62        return entry.second < std::min(planned_sends.at(entry.first), max_send_attempts);
63    }};
64
65    const auto ExistentOrNewNodeId = [&next_nodeid, &fdp](){
66        if (next_nodeid == 0 || fdp.ConsumeBool()) {
67            return next_nodeid++;
68        }
69        return fdp.ConsumeIntegralInRange<NodeId>(0, next_nodeid - 1);
70    };
71
72    LIMITED_WHILE (fdp.ConsumeBool(), 10000) {
73        CallOneOf(
74            fdp,
75            [&] { // Add()
76                CTransactionRef tx;
77                if (transactions.empty() || fdp.ConsumeBool()) {
78                    tx = MakeTransactionRef(ConsumeTransaction(fdp, std::nullopt));
79                } else {
80                    tx = PickIterator(fdp, transactions)->first;
81                }
82
83                auto cleanup_candidates{resolved_transactions};
84                for (const auto& [nodeid, sent_tx] : nodes_sent_to) {
85                    if (!disconnected_nodes.contains(nodeid)) cleanup_candidates.erase(sent_tx);
86                }
87                std::erase_if(transactions, [&](const auto& entry) {
88                    if (!cleanup_candidates.contains(entry.first) || is_pending(entry)) return false;
89                    planned_sends.erase(entry.first);
90                    resolved_transactions.erase(entry.first);
91                    return true;
92                });
93                std::erase_if(nodes_sent_to, [&](const auto& entry) { return !transactions.contains(entry.second); });
94
95                const bool present_before{transactions.contains(tx)};
96                const auto res{pb.Add(tx)};
97                if (present_before) {
98                    auto tx_it{transactions.find(tx)};
99                    Assert(tx_it != transactions.end());
100                    if (tx_it->second < max_send_attempts) {
101                        Assert(res == PrivateBroadcast::AddResult::AlreadyPresent);
102                    } else {
103                        Assert(res == PrivateBroadcast::AddResult::Added);
104                        tx_it->second = 0;
105                        planned_sends[tx] = PrivateBroadcast::INITIAL_CONNECTION_COUNT;
106                        resolved_transactions.erase(tx);
107                        for (auto it = nodes_sent_to.begin(); it != nodes_sent_to.end();) {
108                            if (CTransactionRefComp{}(it->second, tx)) {
109                                it = nodes_sent_to.erase(it);
110                            } else {
111                                ++it;
112                            }
113                        }
114                    }
115                } else if (transactions.size() >= cap) {
116                    Assert(res == PrivateBroadcast::AddResult::QueueFull);
117                } else {
118                    Assert(res == PrivateBroadcast::AddResult::Added);
119                    transactions.emplace(tx, 0);
120                    planned_sends.emplace(tx, PrivateBroadcast::INITIAL_CONNECTION_COUNT);
121                }
122            },
123            [&] { // Remove()
124                if (transactions.empty()) {
125                    return;
126                }
127                const auto transactions_it{PickIterator(fdp, transactions)};
128                const CTransactionRef& tx{transactions_it->first};
129
130                // Remove relevant entries from nodes_sent_to[] if any.
131                for (auto it = nodes_sent_to.begin(); it != nodes_sent_to.end();) {
132                    if (CTransactionRefComp{}(it->second, tx)) {
133                        it = nodes_sent_to.erase(it);
134                    } else {
135                        ++it;
136                    }
137                }
138
139                const auto remaining_sends{pb.Remove(tx)};
140
141                Assert(remaining_sends.has_value());
142                Assert(remaining_sends.value() == std::min(planned_sends.at(tx), max_send_attempts) - transactions_it->second);
143                Assert(!pb.Remove(tx).has_value());
144                planned_sends.erase(tx);
145                resolved_transactions.erase(tx);
146                transactions.erase(transactions_it);
147            },
148            [&] { // MarkResolved()
149                const CTransactionRef tx{transactions.empty() || fdp.ConsumeBool() ?
150                                             MakeTransactionRef(ConsumeTransaction(fdp, std::nullopt)) :
151                                             PickIterator(fdp, transactions)->first};
152                Assert(pb.MarkResolved(tx) == transactions.contains(tx));
153                if (transactions.contains(tx)) resolved_transactions.insert(tx);
154            },
155            [&] { // PickTxForSend()
156                // Only give pristine node ids to PickTxForSend() as required.
157                const NodeId will_send_to_nodeid{next_nodeid++};
158                const CService will_send_to_address{ConsumeService(fdp)};
159
160                const auto opt_tx{pb.PickTxForSend(will_send_to_nodeid, will_send_to_address)};
161
162                if (opt_tx.has_value()) {
163                    Assert(transactions.contains(opt_tx.value()));
164
165                    // "Number of times picked for sending" is the primary key in Priority's comparison
166                    // (fewest sends = highest priority), so PickTxForSend() must return a transaction
167                    // with the minimum send count of any in the queue. Ties are broken by state we
168                    // don't model, so only check this key.
169                    auto pending_transactions{transactions | std::views::filter(is_pending)};
170                    const size_t min_picked{std::ranges::min_element(
171                        pending_transactions, {}, [](const auto& el) { return el.second; })->second};
172                    const auto picked_it{transactions.find(opt_tx.value())};
173                    Assert(picked_it != transactions.end());
174                    Assert(picked_it->second == min_picked); // picked the least-sent transaction
175                    ++picked_it->second; // PickTxForSend() recorded exactly one send
176
177                    const auto& [_, inserted]{nodes_sent_to.emplace(will_send_to_nodeid, opt_tx.value())};
178                    Assert(inserted);
179                } else {
180                    Assert(std::ranges::none_of(transactions, is_pending));
181                }
182            },
183            [&] { // GetTxForNode()
184                const NodeId nodeid{ExistentOrNewNodeId()};
185
186                const auto opt_tx{pb.GetTxForNode(nodeid)};
187
188                if (nodes_sent_to.contains(nodeid)) {
189                    Assert(opt_tx.has_value());
190                    Assert(transactions.contains(opt_tx.value()));
191                    Assert(opt_tx.value() == nodes_sent_to.at(nodeid));
192                } else {
193                    Assert(!opt_tx.has_value());
194                }
195            },
196            [&] { // NodeConfirmedReception()
197                const NodeId nodeid{ExistentOrNewNodeId()};
198
199                pb.NodeConfirmedReception(nodeid);
200            },
201            [&] { // NodeDisconnected()
202                const NodeId nodeid{ExistentOrNewNodeId()};
203                pb.NodeDisconnected(nodeid);
204                if (nodes_sent_to.contains(nodeid)) disconnected_nodes.insert(nodeid);
205            },
206            [&] { // HavePendingTransactions()
207                if (std::ranges::any_of(transactions, is_pending)) {
208                    Assert(pb.HavePendingTransactions());
209                } else {
210                    Assert(!pb.HavePendingTransactions());
211                }
212            },
213            [&] { // TryGrantRetry()
214                if (transactions.empty()) return;
215                const auto tx_it{PickIterator(fdp, transactions)};
216                auto& count{planned_sends.at(tx_it->first)};
217                const bool can_retry{!resolved_transactions.contains(tx_it->first) && !is_pending(*tx_it) && count < max_send_attempts};
218                Assert(pb.TryGrantRetry(tx_it->first) == can_retry);
219                if (can_retry) ++count;
220            },
221            [&] { // GetStale()
222                const auto stale{pb.GetStale()};
223
224                Assert(stale.size() <= transactions.size());
225
226                for (const auto& stale_tx : stale) {
227                    const auto it{transactions.find(stale_tx)};
228                    Assert(it != transactions.end());
229                    Assert(!resolved_transactions.contains(stale_tx));
230                    Assert(planned_sends.at(stale_tx) < max_send_attempts);
231                }
232            },
233            [&] { // GetBroadcastInfo()
234                const auto all_broadcast_info{pb.GetBroadcastInfo()};
235
236                Assert(all_broadcast_info.size() == transactions.size() - resolved_transactions.size());
237
238                for (const auto& info : all_broadcast_info) {
239                    const auto it{transactions.find(info.tx)};
240                    Assert(it != transactions.end());
241                    Assert(!resolved_transactions.contains(info.tx));
242                    Assert(info.peers.size() == it->second); // exactly the sends we recorded
243                    Assert(info.attempts_remaining == max_send_attempts - it->second);
244                }
245            },
246            [&] {
247                clock_ctx.set(ConsumeTime(fdp));
248            });
249    }
250}

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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