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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 https://opensource.org/license/mit/.
4
5#ifndef BITCOIN_PRIVATE_BROADCAST_H
6#define BITCOIN_PRIVATE_BROADCAST_H
7
8#include <net.h>
9#include <primitives/transaction.h>
10#include <primitives/transaction_identifier.h>
11#include <sync.h>
12#include <util/time.h>
13
14#include <optional>
15#include <tuple>
16#include <unordered_map>
17#include <vector>
18
19/**
20 * Store a list of transactions to be broadcast privately. Supports the following operations:
21 * - Add a new transaction
22 * - Remove a transaction
23 * - Mark a transaction as resolved, so no more retry send attempts are granted
24 * - Mark a connection finished
25 * - Grant an additional send attempt for an unresolved transaction
26 * - Pick a transaction for sending to one recipient
27 * - Query which transaction has been picked for sending to a given recipient node
28 * - Mark that a given recipient node has confirmed receipt of a transaction
29 * - Query whether any transactions that need sending are currently on the list
30 */
31class PrivateBroadcast
32{
33public:
34
35    /// Number of connections to make for initial broadcast.
36    static constexpr size_t INITIAL_CONNECTION_COUNT{3};
37
38    /// If a transaction is not sent to any peer for this duration,
39    /// then we consider it stale / for rebroadcasting.
40    static constexpr auto INITIAL_STALE_DURATION{5min};
41
42    /// If a transaction is not received back from the network for this duration
43    /// after it is broadcast, then we consider it stale / for rebroadcasting.
44    static constexpr auto STALE_DURATION{1min};
45
46    /// Maximum number of transactions tracked simultaneously.
47    /// Additions that would exceed this are rejected (see Add()).
48    static constexpr size_t MAX_TRANSACTIONS{10'000};
49
50    /// Maximum number of send attempts for a transaction. Once this limit is
51    /// reached, the transaction remains tracked but is not sent again unless
52    /// explicitly re-added.
53    static constexpr size_t MAX_SEND_ATTEMPTS{1'000};
54
55    /// @param[in] max_transactions Cap on the number of simultaneously tracked
56    /// transactions. Defaults to MAX_TRANSACTIONS.
57    /// @param[in] max_send_attempts Cap on the number of send attempts per
58    /// transaction. Defaults to MAX_SEND_ATTEMPTS.
59    explicit PrivateBroadcast(size_t max_transactions = MAX_TRANSACTIONS,
60                              size_t max_send_attempts = MAX_SEND_ATTEMPTS)
61        : m_max_transactions{max_transactions}, m_max_send_attempts{max_send_attempts} {}
62
63    struct PeerSendInfo {
64        CService address;
65        NodeClock::time_point sent;
66        std::optional<NodeClock::time_point> received;
67    };
68
69    struct TxBroadcastInfo {
70        CTransactionRef tx;
71        NodeClock::time_point time_added;
72        /// Number of additional send attempts allowed for this transaction (0 if exhausted).
73        size_t attempts_remaining;
74        std::vector<PeerSendInfo> peers;
75    };
76
77    /// Outcome of Add().
78    enum class AddResult {
79        //! The transaction was newly added or reset after exhausting its send attempts.
80        Added,
81        //! The transaction was already present with send attempts remaining; no change.
82        AlreadyPresent,
83        //! Rejected: the queue is already at MAX_TRANSACTIONS.
84        QueueFull,
85    };
86
87    /**
88     * Add a transaction to the storage, or reset an exhausted transaction so it
89     * can be broadcast again.
90     * @param[in] tx The transaction to add.
91     * @return Whether the transaction was newly added or reset, was already
92     * present with send attempts remaining, or was rejected because the queue is
93     * full (see AddResult).
94     */
95    [[nodiscard]] AddResult Add(const CTransactionRef& tx)
96        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
97
98    /**
99     * Forget a transaction.
100     * @param[in] tx Transaction to forget.
101     * @retval !nullopt The number of planned send attempts not yet picked
102     * (if the transaction existed and was removed).
103     * @retval nullopt The transaction was not in the storage.
104     */
105    std::optional<size_t> Remove(const CTransactionRef& tx)
106        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
107
108    /**
109     * Mark a transaction as resolved because it was received back from the network
110     * or is no longer acceptable to the mempool.
111     * @param[in] tx Transaction to resolve.
112     * @return Whether the transaction was found in the storage.
113     */
114    bool MarkResolved(const CTransactionRef& tx)
115        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
116
117    /**
118     * Mark a connection finished.
119     * @param[in] nodeid Node whose connection has ended.
120     */
121    void NodeDisconnected(NodeId nodeid)
122        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
123
124    /**
125     * Grant one additional send attempt if the transaction is unresolved, all
126     * planned sends have been picked, and the attempt limit has not been reached.
127     * The caller schedules the connection separately.
128     * @param[in] tx Transaction to retry.
129     * @return Whether an additional send attempt was granted.
130     */
131    bool TryGrantRetry(const CTransactionRef& tx)
132        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
133
134    /**
135     * Pick the transaction with the fewest send attempts, and confirmations,
136     * and oldest send/confirm times.
137     * @param[in] will_send_to_nodeid Will remember that the returned transaction
138     * was picked for sending to this node. Calling this method more than once with
139     * the same `will_send_to_nodeid` is not allowed because sending more than one
140     * transaction to one node would be a privacy leak.
141     * @param[in] will_send_to_address Address of the peer to which this transaction
142     * will be sent.
143     * @return Most urgent transaction or nullopt if there are no transactions
144     * with send attempts remaining.
145     */
146    std::optional<CTransactionRef> PickTxForSend(const NodeId& will_send_to_nodeid, const CService& will_send_to_address)
147        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
148
149    /**
150     * Get the transaction that was picked for sending to a given node by PickTxForSend().
151     * @param[in] nodeid Node to which a transaction is being (or was) sent.
152     * @return Transaction or nullopt if the nodeid is unknown.
153     */
154    std::optional<CTransactionRef> GetTxForNode(const NodeId& nodeid)
155        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
156
157    /**
158     * Mark that the node has confirmed reception of the transaction we sent it by
159     * responding with `PONG` to our `PING` message.
160     * @param[in] nodeid Node that we sent a transaction to.
161     */
162    void NodeConfirmedReception(const NodeId& nodeid)
163        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
164
165    /**
166     * Check if there are transactions with send attempts remaining.
167     */
168    bool HavePendingTransactions()
169        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
170
171    /**
172     * Get the transactions that have not been broadcast recently and have send
173     * attempts remaining.
174     */
175    std::vector<CTransactionRef> GetStale() const
176        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
177
178    /**
179     * Get stats about all transactions currently being privately broadcast.
180     */
181    std::vector<TxBroadcastInfo> GetBroadcastInfo() const
182        EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
183
184private:
185    /// Status of a transaction sent to a given node.
186    struct SendStatus {
187        /// Node to which the transaction will be sent (or was sent).
188        const NodeId nodeid;
189        /// Address of the node.
190        const CService address;
191        /// When was the transaction picked for sending to the node.
192        const NodeClock::time_point picked;
193        /// When was the transaction reception confirmed by the node (by PONG).
194        std::optional<NodeClock::time_point> confirmed;
195        /// Whether the node has disconnected.
196        bool disconnected{false};
197
198        SendStatus(const NodeId& nodeid, const CService& address, const NodeClock::time_point& picked) : nodeid{nodeid}, address{address}, picked{picked} {}
199    };
200
201    /// Cumulative stats from all the send attempts for a transaction. Used to prioritize transactions.
202    struct Priority {
203        size_t num_picked{0}; ///< Number of times the transaction was picked for sending.
204        NodeClock::time_point last_picked{}; ///< The most recent time when the transaction was picked for sending.
205        size_t num_confirmed{0}; ///< Number of nodes that have confirmed reception of a transaction (by PONG).
206        NodeClock::time_point last_confirmed{}; ///< The most recent time when the transaction was confirmed.
207
208        auto operator<=>(const Priority& other) const
209        {
210            // Invert `other` and `this` in the comparison because smaller num_picked, num_confirmed or
211            // earlier times mean greater priority. In other words, if this.num_picked < other.num_picked
212            // then this > other.
213            return std::tie(other.num_picked, other.num_confirmed, other.last_picked, other.last_confirmed) <=>
214                   std::tie(num_picked, num_confirmed, last_picked, last_confirmed);
215        }
216    };
217
218    /// A pair of a transaction and a sent status for a given node. Convenience return type of GetSendStatusByNode().
219    struct TxAndSendStatusForNode {
220        const CTransactionRef& tx;
221        SendStatus& send_status;
222    };
223
224    // No need for salted hasher because we are going to store just a bunch of locally originating transactions.
225
226    struct CTransactionRefHash {
227        size_t operator()(const CTransactionRef& tx) const
228        {
229            return static_cast<size_t>(tx->GetWitnessHash().ToUint256().GetUint64(0));
230        }
231    };
232
233    struct CTransactionRefComp {
234        bool operator()(const CTransactionRef& a, const CTransactionRef& b) const
235        {
236            return a->GetWitnessHash() == b->GetWitnessHash(); // If wtxid equals, then txid also equals.
237        }
238    };
239
240    /**
241     * Derive the sending priority of a transaction.
242     * @param[in] sent_to List of nodes that the transaction has been sent to.
243     */
244    static Priority DerivePriority(const std::vector<SendStatus>& sent_to);
245
246    /**
247     * Find which transaction we sent to a given node (marked by PickTxForSend()).
248     * @return That transaction together with the send status or nullopt if we did not
249     * send any transaction to the given node.
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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