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1// Copyright (c) 2022-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_POLICY_TRUC_POLICY_H
6#define BITCOIN_POLICY_TRUC_POLICY_H
7
8#include <consensus/amount.h>
9#include <policy/packages.h>
10#include <policy/policy.h>
11#include <primitives/transaction.h>
12#include <txmempool.h>
13#include <util/result.h>
14
15#include <set>
16#include <string>
17
18// This module enforces rules for BIP 431 TRUC transactions which help make
19// RBF abilities more robust. A transaction with version=3 is treated as TRUC.
20inline constexpr decltype(CTransaction::version) TRUC_VERSION{3};
21
22// TRUC only allows 1 parent and 1 child when unconfirmed. This translates to a descendant set size
23// of 2 and ancestor set size of 2.
24/** Maximum number of transactions including an unconfirmed tx and its descendants. */
25inline constexpr unsigned int TRUC_DESCENDANT_LIMIT{2};
26/** Maximum number of transactions including a TRUC tx and all its mempool ancestors. */
27inline constexpr unsigned int TRUC_ANCESTOR_LIMIT{2};
28
29/** Maximum sigop-adjusted virtual size of all v3 transactions. */
30inline constexpr int64_t TRUC_MAX_VSIZE{10'000};
31inline constexpr int64_t TRUC_MAX_WEIGHT{TRUC_MAX_VSIZE * WITNESS_SCALE_FACTOR};
32/** Maximum sigop-adjusted virtual size of a tx which spends from an unconfirmed TRUC transaction. */
33inline constexpr int64_t TRUC_CHILD_MAX_VSIZE{1000};
34inline constexpr int64_t TRUC_CHILD_MAX_WEIGHT{TRUC_CHILD_MAX_VSIZE * WITNESS_SCALE_FACTOR};
35// These limits are within the default cluster limits.
36static_assert(TRUC_MAX_VSIZE + TRUC_CHILD_MAX_VSIZE <= DEFAULT_CLUSTER_SIZE_LIMIT_KVB * 1000);
37
38/** Must be called for every transaction, even if not TRUC. Not strictly necessary for transactions
39 * accepted through AcceptMultipleTransactions.
40 *
41 * Checks the following rules:
42 * 1. A TRUC tx must only have TRUC unconfirmed ancestors.
43 * 2. A non-TRUC tx must only have non-TRUC unconfirmed ancestors.
44 * 3. A TRUC's ancestor set, including itself, must be within TRUC_ANCESTOR_LIMIT.
45 * 4. A TRUC's descendant set, including itself, must be within TRUC_DESCENDANT_LIMIT.
46 * 5. If a TRUC tx has any unconfirmed ancestors, the tx's sigop-adjusted vsize must be within
47 * TRUC_CHILD_MAX_VSIZE.
48 * 6. A TRUC tx must be within TRUC_MAX_VSIZE.
49 *
50 *
51 * @param[in]   pool                    A reference to the mempool.
52 * @param[in]   mempool_parents         The in-mempool ancestors of ptx.
53 * @param[in]   direct_conflicts        In-mempool transactions this tx conflicts with. These conflicts
54 *                                      are used to more accurately calculate the resulting descendant
55 *                                      count of in-mempool ancestors.
56 * @param[in]   vsize                   The sigop-adjusted virtual size of ptx.
57 *
58 * @returns 3 possibilities:
59 * - std::nullopt if all TRUC checks were applied successfully
60 * - debug string + pointer to a mempool sibling if this transaction would be the second child in a
61 *   1-parent-1-child cluster; the caller may consider evicting the specified sibling or return an
62 *   error with the debug string.
63 * - debug string + nullptr if this transaction violates some TRUC rule and sibling eviction is not
64 *   applicable.
65 */
66std::optional<std::pair<std::string, CTransactionRef>> SingleTRUCChecks(const CTxMemPool& pool, const CTransactionRef& ptx,
67                                          const std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef>& mempool_parents,
68                                          const std::set<Txid>& direct_conflicts,
69                                          int64_t vsize) EXCLUSIVE_LOCKS_REQUIRED(pool.cs);
70
71/** Must be called for every transaction that is submitted within a package, even if not TRUC.
72 *
73 * For each transaction in a package:
74 * If it's not a TRUC transaction, verify it has no direct TRUC parents in the mempool or the package.
75
76 * If it is a TRUC transaction, verify that any direct parents in the mempool or the package are TRUC.
77 * If such a parent exists, verify that parent has no other children in the package or the mempool,
78 * and that the transaction itself has no children in the package.
79 *
80 * If any TRUC violations in the package exist, this test will fail for one of them:
81 * - if a TRUC transaction T has a parent in the mempool and a child in the package, then PTRUCC(T) will fail
82 * - if a TRUC transaction T has a parent in the package and a child in the package, then PTRUCC(T) will fail
83 * - if a TRUC transaction T and a TRUC (sibling) transaction U have some parent in the mempool,
84 *   then PTRUCC(T) and PTRUCC(U) will fail
85 * - if a TRUC transaction T and a TRUC (sibling) transaction U have some parent in the package,
86 *   then PTRUCC(T) and PTRUCC(U) will fail
87 * - if a TRUC transaction T has a parent P and a grandparent G in the package, then
88 *   PTRUCC(P) will fail (though PTRUCC(G) and PTRUCC(T) might succeed).
89 *
90 * @returns debug string if an error occurs, std::nullopt otherwise.
91 * */
92std::optional<std::string> PackageTRUCChecks(const CTxMemPool& pool, const CTransactionRef& ptx, int64_t vsize,
93                                           const Package& package,
94                                           const std::vector<CTxMemPoolEntry::CTxMemPoolEntryRef>& mempool_parents) EXCLUSIVE_LOCKS_REQUIRED(pool.cs);
95
96#endif // BITCOIN_POLICY_TRUC_POLICY_H
97

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

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