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1// Copyright (c) 2021-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_TXORPHANAGE_H
6#define BITCOIN_NODE_TXORPHANAGE_H
7
8#include <consensus/validation.h>
9#include <net.h>
10#include <primitives/block.h>
11#include <primitives/transaction.h>
12#include <sync.h>
13#include <util/time.h>
14
15#include <map>
16#include <set>
17
18namespace node {
19/** Default value for TxOrphanage::m_reserved_usage_per_peer. Helps limit the total amount of memory used by the orphanage. */
20inline constexpr int64_t DEFAULT_RESERVED_ORPHAN_WEIGHT_PER_PEER{404'000};
21/** Default value for TxOrphanage::m_max_global_latency_score. Helps limit the maximum latency for operations like
22 * EraseForBlock and LimitOrphans. */
23inline constexpr unsigned int DEFAULT_MAX_ORPHANAGE_LATENCY_SCORE{3'000};
24
25// Keep the connection caps below the default global latency limit to avoid a zero per-peer share.
26static_assert(MAX_PEER_CONNECTIONS + MAX_ADDNODE_CONNECTIONS + MAX_PRIVATE_BROADCAST_CONNECTIONS < DEFAULT_MAX_ORPHANAGE_LATENCY_SCORE);
27
28/** A class to track orphan transactions (failed on TX_MISSING_INPUTS)
29 * Since we cannot distinguish orphans from bad transactions with non-existent inputs, we heavily limit the amount of
30 * announcements (unique (NodeId, wtxid) pairs), the number of inputs, and size of the orphans stored (both individual
31 * and summed). We also try to prevent adversaries from churning this data structure: once global limits are reached, we
32 * continuously evict the oldest announcement (sorting non-reconsiderable orphans before reconsiderable ones) from the
33 * most resource-intensive peer until we are back within limits.
34 * - Peers can exceed their individual limits (e.g. because they are very useful transaction relay peers) as long as the
35 *   global limits are not exceeded.
36 * - As long as the orphan has 1 announcer, it remains in the orphanage.
37 * - No peer can trigger the eviction of another peer's orphans.
38 * - Peers' orphans are effectively protected from eviction as long as they don't exceed their limits.
39 * Not thread-safe. Requires external synchronization.
40 */
41class TxOrphanage {
42public:
43    using Usage = int64_t;
44    using Count = unsigned int;
45
46    /** Allows providing orphan information externally */
47    struct OrphanInfo {
48        CTransactionRef tx;
49        /** Peers added with AddTx or AddAnnouncer. */
50        std::set<NodeId> announcers;
51
52        // Constructor with moved announcers
53        OrphanInfo(CTransactionRef tx, std::set<NodeId>&& announcers) :
54            tx(std::move(tx)),
55            announcers(std::move(announcers))
56        {}
57    };
58
59    virtual ~TxOrphanage() = default;
60
61    /** Add a new orphan transaction */
62    virtual bool AddTx(const CTransactionRef& tx, NodeId peer) = 0;
63
64    /** Add an additional announcer to an orphan if it exists. Otherwise, do nothing. */
65    virtual bool AddAnnouncer(const Wtxid& wtxid, NodeId peer) = 0;
66
67    /** Get a transaction by its witness txid */
68    virtual CTransactionRef GetTx(const Wtxid& wtxid) const = 0;
69
70    /** Check if we already have an orphan transaction (by wtxid only) */
71    virtual bool HaveTx(const Wtxid& wtxid) const = 0;
72
73    /** Check if a {tx, peer} exists in the orphanage.*/
74    virtual bool HaveTxFromPeer(const Wtxid& wtxid, NodeId peer) const = 0;
75
76    /** Extract a transaction from a peer's work set, and flip it back to non-reconsiderable.
77     *  Returns nullptr if there are no transactions to work on.
78     *  Otherwise returns the transaction reference, and removes
79     *  it from the work set.
80     */
81    virtual CTransactionRef GetTxToReconsider(NodeId peer) = 0;
82
83    /** Erase an orphan by wtxid, including all announcements if there are multiple.
84     * Returns true if an orphan was erased, false if no tx with this wtxid exists. */
85    virtual bool EraseTx(const Wtxid& wtxid) = 0;
86
87    /** Maybe erase all orphans announced by a peer (eg, after that peer disconnects). If an orphan
88     * has been announced by another peer, don't erase, just remove this peer from the list of announcers. */
89    virtual void EraseForPeer(NodeId peer) = 0;
90
91    /** Erase all orphans included in or invalidated by a new block */
92    virtual void EraseForBlock(const CBlock& block) = 0;
93
94    /** Add any orphans that list a particular tx as a parent into the from peer's work set */
95    virtual std::vector<std::pair<Wtxid, NodeId>> AddChildrenToWorkSet(const CTransaction& tx, FastRandomContext& rng) = 0;
96
97    /** Does this peer have any work to do? */
98    virtual bool HaveTxToReconsider(NodeId peer) = 0;
99
100    /** Get all children that spend from this tx and were received from nodeid. Sorted
101     * reconsiderable before non-reconsiderable, then from most recent to least recent. */
102    virtual std::vector<CTransactionRef> GetChildrenFromSamePeer(const CTransactionRef& parent, NodeId nodeid) const = 0;
103
104    /** Get all orphan transactions */
105    virtual std::vector<OrphanInfo> GetOrphanTransactions() const = 0;
106
107    /** Get the total usage (weight) of all orphans. If an orphan has multiple announcers, its usage is
108     * only counted once within this total. */
109    virtual Usage TotalOrphanUsage() const = 0;
110
111    /** Total usage (weight) of orphans for which this peer is an announcer. If an orphan has multiple
112     * announcers, its weight will be accounted for in each PeerOrphanInfo, so the total of all
113     * peers' UsageByPeer() may be larger than TotalOrphanUsage(). Similarly, UsageByPeer() may be far higher than
114     * ReservedPeerUsage(), particularly if many peers have provided the same orphans. */
115    virtual Usage UsageByPeer(NodeId peer) const = 0;
116
117    /** Check consistency between PeerOrphanInfo and m_orphans. Recalculate counters and ensure they
118     * match what is cached. */
119    virtual void SanityCheck() const = 0;
120
121    /** Number of announcements, i.e. total size of m_orphans. Ones for the same wtxid are not de-duplicated.
122     * Not the same as TotalLatencyScore(). */
123    virtual Count CountAnnouncements() const = 0;
124
125    /** Number of unique orphans (by wtxid). */
126    virtual Count CountUniqueOrphans() const = 0;
127
128    /** Number of orphans stored from this peer. */
129    virtual Count AnnouncementsFromPeer(NodeId peer) const = 0;
130
131    /** Latency score of transactions announced by this peer. */
132    virtual Count LatencyScoreFromPeer(NodeId peer) const = 0;
133
134    /** Get the maximum global latency score allowed */
135    virtual Count MaxGlobalLatencyScore() const = 0;
136
137    /** Get the total latency score of all orphans */
138    virtual Count TotalLatencyScore() const = 0;
139
140    /** Get the reserved usage per peer */
141    virtual Usage ReservedPeerUsage() const = 0;
142
143    /** Get the maximum latency score allowed per peer */
144    virtual Count MaxPeerLatencyScore() const = 0;
145
146    /** Get the maximum global usage allowed */
147    virtual Usage MaxGlobalUsage() const = 0;
148};
149
150/** Create a new TxOrphanage instance */
151std::unique_ptr<TxOrphanage> MakeTxOrphanage() noexcept;
152std::unique_ptr<TxOrphanage> MakeTxOrphanage(TxOrphanage::Count max_global_latency_score, TxOrphanage::Usage reserved_peer_usage) noexcept;
153} // namespace node
154#endif // BITCOIN_NODE_TXORPHANAGE_H
155

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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