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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#ifndef BITCOIN_NODE_TXDOWNLOADMAN_H
6#define BITCOIN_NODE_TXDOWNLOADMAN_H
7
8#include <net.h>
9#include <node/txorphanage.h>
10#include <policy/packages.h>
11
12#include <cstdint>
13#include <memory>
14
15class CBlock;
16class CRollingBloomFilter;
17class CTxMemPool;
18class GenTxid;
19class TxRequestTracker;
20namespace node {
21class TxDownloadManagerImpl;
22
23/** Maximum number of in-flight transaction requests from a peer. It is not a hard limit, but the threshold at which
24 *  point the OVERLOADED_PEER_TX_DELAY kicks in. */
25inline constexpr int32_t MAX_PEER_TX_REQUEST_IN_FLIGHT = 100;
26/** Maximum number of transactions to consider for requesting, per peer. It provides a reasonable DoS limit to
27 *  per-peer memory usage spent on announcements, while covering peers continuously sending INVs at the maximum
28 *  rate (by our own policy, see DEFAULT_TX_SEND_RATE) for several minutes, while not receiving
29 *  the actual transaction (from any peer) in response to requests for them. */
30inline constexpr int32_t MAX_PEER_TX_ANNOUNCEMENTS = 5000;
31/** How long to delay requesting transactions via txids, if we have wtxid-relaying peers */
32inline constexpr auto TXID_RELAY_DELAY{2s};
33/** How long to delay requesting transactions from non-preferred peers */
34inline constexpr auto NONPREF_PEER_TX_DELAY{2s};
35/** How long to delay requesting transactions from overloaded peers (see MAX_PEER_TX_REQUEST_IN_FLIGHT). */
36inline constexpr auto OVERLOADED_PEER_TX_DELAY{2s};
37/** How long to wait before downloading a transaction from an additional peer */
38inline constexpr auto GETDATA_TX_INTERVAL{60s};
39struct TxDownloadOptions {
40    /** Read-only reference to mempool. */
41    const CTxMemPool& m_mempool;
42    /** Instantiate TxRequestTracker as deterministic (used for tests). */
43    bool m_deterministic_txrequest{false};
44};
45struct TxDownloadConnectionInfo {
46    /** Whether this peer is preferred for transaction download. */
47    const bool m_preferred;
48    /** Whether this peer has Relay permissions. */
49    const bool m_relay_permissions;
50    /** Whether this peer supports wtxid relay. */
51    const bool m_wtxid_relay;
52};
53struct PackageToValidate {
54    Package m_txns;
55    std::vector<NodeId> m_senders;
56    /** Construct a 1-parent-1-child package. */
57    explicit PackageToValidate(const CTransactionRef& parent,
58                               const CTransactionRef& child,
59                               NodeId parent_sender,
60                               NodeId child_sender) :
61        m_txns{parent, child},
62        m_senders{parent_sender, child_sender}
63    {}
64
65    // Move ctor
66    PackageToValidate(PackageToValidate&& other) : m_txns{std::move(other.m_txns)}, m_senders{std::move(other.m_senders)} {}
67    // Copy ctor
68    PackageToValidate(const PackageToValidate& other) = default;
69
70    // Move assignment
71    PackageToValidate& operator=(PackageToValidate&& other) {
72        this->m_txns = std::move(other.m_txns);
73        this->m_senders = std::move(other.m_senders);
74        return *this;
75    }
76
77    std::string ToString() const {
78        Assume(m_txns.size() == 2);
79        return strprintf("parent %s (wtxid=%s, sender=%d) + child %s (wtxid=%s, sender=%d)",
80                         m_txns.front()->GetHash().ToString(),
81                         m_txns.front()->GetWitnessHash().ToString(),
82                         m_senders.front(),
83                         m_txns.back()->GetHash().ToString(),
84                         m_txns.back()->GetWitnessHash().ToString(),
85                         m_senders.back());
86    }
87};
88struct RejectedTxTodo
89{
90    bool m_should_add_extra_compact_tx;
91    std::vector<Txid> m_unique_parents;
92    std::optional<PackageToValidate> m_package_to_validate;
93};
94
95
96/**
97 * Class responsible for deciding what transactions to request and, once
98 * downloaded, whether and how to validate them. It is also responsible for
99 * deciding what transaction packages to validate and how to resolve orphan
100 * transactions. Its data structures include TxRequestTracker for scheduling
101 * requests, rolling bloom filters for remembering transactions that have
102 * already been {accepted, rejected, confirmed}, an orphanage, and a registry of
103 * each peer's transaction relay-related information.
104 *
105 * Caller needs to interact with TxDownloadManager:
106 * - ValidationInterface callbacks.
107 * - When a potential transaction relay peer connects or disconnects.
108 * - When a transaction or package is accepted or rejected from mempool
109 * - When a inv, notfound, or tx message is received
110 * - To get instructions for which getdata messages to send
111 *
112 * This class is not thread-safe. Access must be synchronized using an
113 * external mutex.
114 */
115class TxDownloadManager {
116    const std::unique_ptr<TxDownloadManagerImpl> m_impl;
117
118public:
119    explicit TxDownloadManager(const TxDownloadOptions& options);
120    ~TxDownloadManager();
121
122    // Responses to chain events. TxDownloadManager is not an actual client of ValidationInterface, these are called through PeerManager.
123    void ActiveTipChange();
124    void BlockConnected(const std::shared_ptr<const CBlock>& pblock);
125    void BlockDisconnected();
126
127    /** Creates a new PeerInfo. Saves the connection info to calculate tx announcement delays later. */
128    void ConnectedPeer(NodeId nodeid, const TxDownloadConnectionInfo& info);
129
130    /** Deletes all txrequest announcements and orphans for a given peer. */
131    void DisconnectedPeer(NodeId nodeid);
132
133    /** Consider adding this tx hash to txrequest. Should be called whenever a new inv has been received.
134     * Also called internally when a transaction is missing parents so that we can request them.
135     * Returns true if this was a dropped inv (p2p_inv=true and we already have the tx), false otherwise. */
136    bool AddTxAnnouncement(NodeId peer, const GenTxid& gtxid, std::chrono::microseconds now);
137
138    /** Get getdata requests to send. */
139    std::vector<GenTxid> GetRequestsToSend(NodeId nodeid, std::chrono::microseconds current_time);
140
141    /** Should be called when a notfound for a tx has been received. */
142    void ReceivedNotFound(NodeId nodeid, const std::vector<GenTxid>& gtxids);
143
144    /** Respond to successful transaction submission to mempool */
145    void MempoolAcceptedTx(const CTransactionRef& tx);
146
147    /** Respond to transaction rejected from mempool */
148    RejectedTxTodo MempoolRejectedTx(const CTransactionRef& ptx, const TxValidationState& state, NodeId nodeid, bool first_time_failure);
149
150    /** Respond to package rejected from mempool */
151    void MempoolRejectedPackage(const Package& package);
152
153    /** Marks a tx as ReceivedResponse in txrequest and checks whether AlreadyHaveTx.
154     * Return a bool indicating whether this tx should be validated. If false, optionally, a
155     * PackageToValidate. */
156    std::pair<bool, std::optional<PackageToValidate>> ReceivedTx(NodeId nodeid, const CTransactionRef& ptx);
157
158    /** Whether there are any orphans to reconsider for this peer. */
159    bool HaveMoreWork(NodeId nodeid) const;
160
161    /** Returns next orphan tx to consider, or nullptr if none exist. */
162    CTransactionRef GetTxToReconsider(NodeId nodeid);
163
164    /** Check that all data structures are empty. */
165    void CheckIsEmpty() const;
166
167    /** Check that all data structures that track per-peer information have nothing for this peer. */
168    void CheckIsEmpty(NodeId nodeid) const;
169
170    /** Wrapper for TxOrphanage::GetOrphanTransactions */
171    std::vector<TxOrphanage::OrphanInfo> GetOrphanTransactions() const;
172};
173} // namespace node
174#endif // BITCOIN_NODE_TXDOWNLOADMAN_H
175

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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