diff options
Diffstat (limited to 'src/validation.cpp')
-rw-r--r-- | src/validation.cpp | 197 |
1 files changed, 133 insertions, 64 deletions
diff --git a/src/validation.cpp b/src/validation.cpp index e3a00e4241..6e0addc877 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -456,7 +456,7 @@ public: * any transaction spending the same inputs as a transaction in the mempool is considered * a conflict. */ const bool m_allow_replacement; - /** When true, the mempool will not be trimmed when individual transactions are submitted in + /** When true, the mempool will not be trimmed when any transactions are submitted in * Finalize(). Instead, limits should be enforced at the end to ensure the package is not * partially submitted. */ @@ -517,7 +517,7 @@ public: /* m_coins_to_uncache */ package_args.m_coins_to_uncache, /* m_test_accept */ package_args.m_test_accept, /* m_allow_replacement */ true, - /* m_package_submission */ false, + /* m_package_submission */ true, // do not LimitMempoolSize in Finalize() /* m_package_feerates */ false, // only 1 transaction }; } @@ -556,6 +556,19 @@ public: PackageMempoolAcceptResult AcceptMultipleTransactions(const std::vector<CTransactionRef>& txns, ATMPArgs& args) EXCLUSIVE_LOCKS_REQUIRED(cs_main); /** + * Submission of a subpackage. + * If subpackage size == 1, calls AcceptSingleTransaction() with adjusted ATMPArgs to avoid + * package policy restrictions like no CPFP carve out (PackageMempoolChecks) and disabled RBF + * (m_allow_replacement), and creates a PackageMempoolAcceptResult wrapping the result. + * + * If subpackage size > 1, calls AcceptMultipleTransactions() with the provided ATMPArgs. + * + * Also cleans up all non-chainstate coins from m_view at the end. + */ + PackageMempoolAcceptResult AcceptSubPackage(const std::vector<CTransactionRef>& subpackage, ATMPArgs& args) + EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs); + + /** * Package (more specific than just multiple transactions) acceptance. Package must be a child * with all of its unconfirmed parents, and topologically sorted. */ @@ -640,10 +653,9 @@ private: // Submit all transactions to the mempool and call ConsensusScriptChecks to add to the script // cache - should only be called after successful validation of all transactions in the package. - // The package may end up partially-submitted after size limiting; returns true if all - // transactions are successfully added to the mempool, false otherwise. + // Does not call LimitMempoolSize(), so mempool max_size_bytes may be temporarily exceeded. bool SubmitPackage(const ATMPArgs& args, std::vector<Workspace>& workspaces, PackageValidationState& package_state, - std::map<const uint256, const MempoolAcceptResult>& results) + std::map<uint256, MempoolAcceptResult>& results) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs); // Compare a package's feerate against minimum allowed. @@ -1125,7 +1137,7 @@ bool MemPoolAccept::Finalize(const ATMPArgs& args, Workspace& ws) bool MemPoolAccept::SubmitPackage(const ATMPArgs& args, std::vector<Workspace>& workspaces, PackageValidationState& package_state, - std::map<const uint256, const MempoolAcceptResult>& results) + std::map<uint256, MempoolAcceptResult>& results) { AssertLockHeld(cs_main); AssertLockHeld(m_pool.cs); @@ -1180,32 +1192,21 @@ bool MemPoolAccept::SubmitPackage(const ATMPArgs& args, std::vector<Workspace>& } } - // It may or may not be the case that all the transactions made it into the mempool. Regardless, - // make sure we haven't exceeded max mempool size. - LimitMempoolSize(m_pool, m_active_chainstate.CoinsTip()); - std::vector<uint256> all_package_wtxids; all_package_wtxids.reserve(workspaces.size()); std::transform(workspaces.cbegin(), workspaces.cend(), std::back_inserter(all_package_wtxids), [](const auto& ws) { return ws.m_ptx->GetWitnessHash(); }); - // Find the wtxids of the transactions that made it into the mempool. Allow partial submission, - // but don't report success unless they all made it into the mempool. + + // Add successful results. The returned results may change later if LimitMempoolSize() evicts them. for (Workspace& ws : workspaces) { const auto effective_feerate = args.m_package_feerates ? ws.m_package_feerate : CFeeRate{ws.m_modified_fees, static_cast<uint32_t>(ws.m_vsize)}; const auto effective_feerate_wtxids = args.m_package_feerates ? all_package_wtxids : std::vector<uint256>({ws.m_ptx->GetWitnessHash()}); - if (m_pool.exists(GenTxid::Wtxid(ws.m_ptx->GetWitnessHash()))) { - results.emplace(ws.m_ptx->GetWitnessHash(), - MempoolAcceptResult::Success(std::move(ws.m_replaced_transactions), ws.m_vsize, - ws.m_base_fees, effective_feerate, effective_feerate_wtxids)); - GetMainSignals().TransactionAddedToMempool(ws.m_ptx, m_pool.GetAndIncrementSequence()); - } else { - all_submitted = false; - ws.m_state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "mempool full"); - package_state.Invalid(PackageValidationResult::PCKG_TX, "transaction failed"); - results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state)); - } + results.emplace(ws.m_ptx->GetWitnessHash(), + MempoolAcceptResult::Success(std::move(ws.m_replaced_transactions), ws.m_vsize, + ws.m_base_fees, effective_feerate, effective_feerate_wtxids)); + GetMainSignals().TransactionAddedToMempool(ws.m_ptx, m_pool.GetAndIncrementSequence()); } return all_submitted; } @@ -1255,7 +1256,7 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptMultipleTransactions(const std:: workspaces.reserve(txns.size()); std::transform(txns.cbegin(), txns.cend(), std::back_inserter(workspaces), [](const auto& tx) { return Workspace(tx); }); - std::map<const uint256, const MempoolAcceptResult> results; + std::map<uint256, MempoolAcceptResult> results; LOCK(m_pool.cs); @@ -1332,6 +1333,54 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptMultipleTransactions(const std:: return PackageMempoolAcceptResult(package_state, std::move(results)); } +PackageMempoolAcceptResult MemPoolAccept::AcceptSubPackage(const std::vector<CTransactionRef>& subpackage, ATMPArgs& args) +{ + AssertLockHeld(::cs_main); + AssertLockHeld(m_pool.cs); + auto result = [&]() EXCLUSIVE_LOCKS_REQUIRED(::cs_main, m_pool.cs) { + if (subpackage.size() > 1) { + return AcceptMultipleTransactions(subpackage, args); + } + const auto& tx = subpackage.front(); + ATMPArgs single_args = ATMPArgs::SingleInPackageAccept(args); + const auto single_res = AcceptSingleTransaction(tx, single_args); + PackageValidationState package_state_wrapped; + if (single_res.m_result_type != MempoolAcceptResult::ResultType::VALID) { + package_state_wrapped.Invalid(PackageValidationResult::PCKG_TX, "transaction failed"); + } + return PackageMempoolAcceptResult(package_state_wrapped, {{tx->GetWitnessHash(), single_res}}); + }(); + // Clean up m_view and m_viewmempool so that other subpackage evaluations don't have access to + // coins they shouldn't. Keep some coins in order to minimize re-fetching coins from the UTXO set. + // + // There are 3 kinds of coins in m_view: + // (1) Temporary coins from the transactions in subpackage, constructed by m_viewmempool. + // (2) Mempool coins from transactions in the mempool, constructed by m_viewmempool. + // (3) Confirmed coins fetched from our current UTXO set. + // + // (1) Temporary coins need to be removed, regardless of whether the transaction was submitted. + // If the transaction was submitted to the mempool, m_viewmempool will be able to fetch them from + // there. If it wasn't submitted to mempool, it is incorrect to keep them - future calls may try + // to spend those coins that don't actually exist. + // (2) Mempool coins also need to be removed. If the mempool contents have changed as a result + // of submitting or replacing transactions, coins previously fetched from mempool may now be + // spent or nonexistent. Those coins need to be deleted from m_view. + // (3) Confirmed coins don't need to be removed. The chainstate has not changed (we are + // holding cs_main and no blocks have been processed) so the confirmed tx cannot disappear like + // a mempool tx can. The coin may now be spent after we submitted a tx to mempool, but + // we have already checked that the package does not have 2 transactions spending the same coin. + // Keeping them in m_view is an optimization to not re-fetch confirmed coins if we later look up + // inputs for this transaction again. + for (const auto& outpoint : m_viewmempool.GetNonBaseCoins()) { + // In addition to resetting m_viewmempool, we also need to manually delete these coins from + // m_view because it caches copies of the coins it fetched from m_viewmempool previously. + m_view.Uncache(outpoint); + } + // This deletes the temporary and mempool coins. + m_viewmempool.Reset(); + return result; +} + PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package& package, ATMPArgs& args) { AssertLockHeld(cs_main); @@ -1388,21 +1437,12 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package& package, m_view.SetBackend(m_dummy); LOCK(m_pool.cs); - // Stores final results that won't change - std::map<const uint256, const MempoolAcceptResult> results_final; - // Node operators are free to set their mempool policies however they please, nodes may receive - // transactions in different orders, and malicious counterparties may try to take advantage of - // policy differences to pin or delay propagation of transactions. As such, it's possible for - // some package transaction(s) to already be in the mempool, and we don't want to reject the - // entire package in that case (as that could be a censorship vector). De-duplicate the - // transactions that are already in the mempool, and only call AcceptMultipleTransactions() with - // the new transactions. This ensures we don't double-count transaction counts and sizes when - // checking ancestor/descendant limits, or double-count transaction fees for fee-related policy. - ATMPArgs single_args = ATMPArgs::SingleInPackageAccept(args); - // Results from individual validation. "Nonfinal" because if a transaction fails by itself but - // succeeds later (i.e. when evaluated with a fee-bumping child), the result changes (though not - // reflected in this map). If a transaction fails more than once, we want to return the first - // result, when it was considered on its own. So changes will only be from invalid -> valid. + // Stores results from which we will create the returned PackageMempoolAcceptResult. + // A result may be changed if a mempool transaction is evicted later due to LimitMempoolSize(). + std::map<uint256, MempoolAcceptResult> results_final; + // Results from individual validation which will be returned if no other result is available for + // this transaction. "Nonfinal" because if a transaction fails by itself but succeeds later + // (i.e. when evaluated with a fee-bumping child), the result in this map may be discarded. std::map<uint256, MempoolAcceptResult> individual_results_nonfinal; bool quit_early{false}; std::vector<CTransactionRef> txns_package_eval; @@ -1414,6 +1454,14 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package& package, // we know is that the inputs aren't available. if (m_pool.exists(GenTxid::Wtxid(wtxid))) { // Exact transaction already exists in the mempool. + // Node operators are free to set their mempool policies however they please, nodes may receive + // transactions in different orders, and malicious counterparties may try to take advantage of + // policy differences to pin or delay propagation of transactions. As such, it's possible for + // some package transaction(s) to already be in the mempool, and we don't want to reject the + // entire package in that case (as that could be a censorship vector). De-duplicate the + // transactions that are already in the mempool, and only call AcceptMultipleTransactions() with + // the new transactions. This ensures we don't double-count transaction counts and sizes when + // checking ancestor/descendant limits, or double-count transaction fees for fee-related policy. auto iter = m_pool.GetIter(txid); assert(iter != std::nullopt); results_final.emplace(wtxid, MempoolAcceptResult::MempoolTx(iter.value()->GetTxSize(), iter.value()->GetFee())); @@ -1432,7 +1480,8 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package& package, } else { // Transaction does not already exist in the mempool. // Try submitting the transaction on its own. - const auto single_res = AcceptSingleTransaction(tx, single_args); + const auto single_package_res = AcceptSubPackage({tx}, args); + const auto& single_res = single_package_res.m_tx_results.at(wtxid); if (single_res.m_result_type == MempoolAcceptResult::ResultType::VALID) { // The transaction succeeded on its own and is now in the mempool. Don't include it // in package validation, because its fees should only be "used" once. @@ -1459,32 +1508,52 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package& package, } } - // Quit early because package validation won't change the result or the entire package has - // already been submitted. - if (quit_early || txns_package_eval.empty()) { - for (const auto& [wtxid, mempoolaccept_res] : individual_results_nonfinal) { - Assume(results_final.emplace(wtxid, mempoolaccept_res).second); - Assume(mempoolaccept_res.m_result_type == MempoolAcceptResult::ResultType::INVALID); + auto multi_submission_result = quit_early || txns_package_eval.empty() ? PackageMempoolAcceptResult(package_state_quit_early, {}) : + AcceptSubPackage(txns_package_eval, args); + PackageValidationState& package_state_final = multi_submission_result.m_state; + + // Make sure we haven't exceeded max mempool size. + // Package transactions that were submitted to mempool or already in mempool may be evicted. + LimitMempoolSize(m_pool, m_active_chainstate.CoinsTip()); + + for (const auto& tx : package) { + const auto& wtxid = tx->GetWitnessHash(); + if (multi_submission_result.m_tx_results.count(wtxid) > 0) { + // We shouldn't have re-submitted if the tx result was already in results_final. + Assume(results_final.count(wtxid) == 0); + // If it was submitted, check to see if the tx is still in the mempool. It could have + // been evicted due to LimitMempoolSize() above. + const auto& txresult = multi_submission_result.m_tx_results.at(wtxid); + if (txresult.m_result_type == MempoolAcceptResult::ResultType::VALID && !m_pool.exists(GenTxid::Wtxid(wtxid))) { + package_state_final.Invalid(PackageValidationResult::PCKG_TX, "transaction failed"); + TxValidationState mempool_full_state; + mempool_full_state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "mempool full"); + results_final.emplace(wtxid, MempoolAcceptResult::Failure(mempool_full_state)); + } else { + results_final.emplace(wtxid, txresult); + } + } else if (const auto it{results_final.find(wtxid)}; it != results_final.end()) { + // Already-in-mempool transaction. Check to see if it's still there, as it could have + // been evicted when LimitMempoolSize() was called. + Assume(it->second.m_result_type != MempoolAcceptResult::ResultType::INVALID); + Assume(individual_results_nonfinal.count(wtxid) == 0); + // Query by txid to include the same-txid-different-witness ones. + if (!m_pool.exists(GenTxid::Txid(tx->GetHash()))) { + package_state_final.Invalid(PackageValidationResult::PCKG_TX, "transaction failed"); + TxValidationState mempool_full_state; + mempool_full_state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "mempool full"); + // Replace the previous result. + results_final.erase(wtxid); + results_final.emplace(wtxid, MempoolAcceptResult::Failure(mempool_full_state)); + } + } else if (const auto it{individual_results_nonfinal.find(wtxid)}; it != individual_results_nonfinal.end()) { + Assume(it->second.m_result_type == MempoolAcceptResult::ResultType::INVALID); + // Interesting result from previous processing. + results_final.emplace(wtxid, it->second); } - return PackageMempoolAcceptResult(package_state_quit_early, std::move(results_final)); - } - // Validate the (deduplicated) transactions as a package. Note that submission_result has its - // own PackageValidationState; package_state_quit_early is unused past this point. - auto submission_result = AcceptMultipleTransactions(txns_package_eval, args); - // Include already-in-mempool transaction results in the final result. - for (const auto& [wtxid, mempoolaccept_res] : results_final) { - Assume(submission_result.m_tx_results.emplace(wtxid, mempoolaccept_res).second); - Assume(mempoolaccept_res.m_result_type != MempoolAcceptResult::ResultType::INVALID); - } - if (submission_result.m_state.GetResult() == PackageValidationResult::PCKG_TX) { - // Package validation failed because one or more transactions failed. Provide a result for - // each transaction; if AcceptMultipleTransactions() didn't return a result for a tx, - // include the previous individual failure reason. - submission_result.m_tx_results.insert(individual_results_nonfinal.cbegin(), - individual_results_nonfinal.cend()); - Assume(submission_result.m_tx_results.size() == package.size()); } - return submission_result; + Assume(results_final.size() == package.size()); + return PackageMempoolAcceptResult(package_state_final, std::move(results_final)); } } // anon namespace |