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glozowariard
glozow
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ariard
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MOVEONLY: context-free package policies
Co-authored-by: ariard <[email protected]>
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4 files changed

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lines changed

‎src/Makefile.am‎

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@@ -348,6 +348,7 @@ libbitcoin_server_a_SOURCES = \
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node/ui_interface.cpp \
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noui.cpp \
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policy/fees.cpp \
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policy/packages.cpp \
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policy/rbf.cpp \
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policy/settings.cpp \
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pow.cpp \

‎src/policy/packages.cpp‎

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@@ -0,0 +1,62 @@
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// Copyright (c) 2021 The Bitcoin Core developers
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// Distributed under the MIT software license, see the accompanying
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// file COPYING or http://www.opensource.org/licenses/mit-license.php.
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#include <consensus/validation.h>
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#include <policy/packages.h>
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#include <primitives/transaction.h>
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#include <uint256.h>
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#include <util/hasher.h>
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#include <numeric>
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#include <unordered_set>
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bool CheckPackage(const Package& txns, PackageValidationState& state)
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{
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const unsigned int package_count = txns.size();
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if (package_count > MAX_PACKAGE_COUNT) {
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return state.Invalid(PackageValidationResult::PCKG_POLICY, "package-too-many-transactions");
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}
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const int64_t total_size = std::accumulate(txns.cbegin(), txns.cend(), 0,
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[](int64_t sum, const auto& tx) { return sum + GetVirtualTransactionSize(*tx); });
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// If the package only contains 1 tx, it's better to report the policy violation on individual tx size.
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if (package_count > 1 && total_size > MAX_PACKAGE_SIZE * 1000) {
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return state.Invalid(PackageValidationResult::PCKG_POLICY, "package-too-large");
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}
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// Require the package to be sorted in order of dependency, i.e. parents appear before children.
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// An unsorted package will fail anyway on missing-inputs, but it's better to quit earlier and
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// fail on something less ambiguous (missing-inputs could also be an orphan or trying to
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// spend nonexistent coins).
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std::unordered_set<uint256, SaltedTxidHasher> later_txids;
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std::transform(txns.cbegin(), txns.cend(), std::inserter(later_txids, later_txids.end()),
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[](const auto& tx) { return tx->GetHash(); });
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for (const auto& tx : txns) {
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for (const auto& input : tx->vin) {
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if (later_txids.find(input.prevout.hash) != later_txids.end()) {
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// The parent is a subsequent transaction in the package.
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return state.Invalid(PackageValidationResult::PCKG_POLICY, "package-not-sorted");
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}
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}
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later_txids.erase(tx->GetHash());
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}
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// Don't allow any conflicting transactions, i.e. spending the same inputs, in a package.
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std::unordered_set<COutPoint, SaltedOutpointHasher> inputs_seen;
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for (const auto& tx : txns) {
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for (const auto& input : tx->vin) {
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if (inputs_seen.find(input.prevout) != inputs_seen.end()) {
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// This input is also present in another tx in the package.
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return state.Invalid(PackageValidationResult::PCKG_POLICY, "conflict-in-package");
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}
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}
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// Batch-add all the inputs for a tx at a time. If we added them 1 at a time, we could
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// catch duplicate inputs within a single tx. This is a more severe, consensus error,
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// and we want to report that from CheckTransaction instead.
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std::transform(tx->vin.cbegin(), tx->vin.cend(), std::inserter(inputs_seen, inputs_seen.end()),
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[](const auto& input) { return input.prevout; });
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}
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return true;
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}

‎src/policy/packages.h‎

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@@ -33,4 +33,12 @@ using Package = std::vector<CTransactionRef>;
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class PackageValidationState : public ValidationState<PackageValidationResult> {};
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/** Context-free package policy checks:
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* 1. The number of transactions cannot exceed MAX_PACKAGE_COUNT.
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* 2. The total virtual size cannot exceed MAX_PACKAGE_SIZE.
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* 3. If any dependencies exist between transactions, parents must appear before children.
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* 4. Transactions cannot conflict, i.e., spend the same inputs.
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*/
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bool CheckPackage(const Package& txns, PackageValidationState& state);
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#endif // BITCOIN_POLICY_PACKAGES_H

‎src/validation.cpp‎

Lines changed: 5 additions & 55 deletions
Original file line numberDiff line numberDiff line change
@@ -1083,65 +1083,15 @@ PackageMempoolAcceptResult MemPoolAccept::AcceptMultipleTransactions(const std::
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{
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AssertLockHeld(cs_main);
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1086+
// These context-free package limits can be done before taking the mempool lock.
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PackageValidationState package_state;
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const unsigned int package_count = txns.size();
1088+
if (!CheckPackage(txns, package_state)) return PackageMempoolAcceptResult(package_state, {});
10881089

1089-
// These context-free package limits can be checked before taking the mempool lock.
1090-
if (package_count > MAX_PACKAGE_COUNT) {
1091-
package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-too-many-transactions");
1092-
return PackageMempoolAcceptResult(package_state, {});
1093-
}
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1095-
const int64_t total_size = std::accumulate(txns.cbegin(), txns.cend(), 0,
1096-
[](int64_t sum, const auto& tx) { return sum + GetVirtualTransactionSize(*tx); });
1097-
// If the package only contains 1 tx, it's better to report the policy violation on individual tx size.
1098-
if (package_count > 1 && total_size > MAX_PACKAGE_SIZE * 1000) {
1099-
package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-too-large");
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return PackageMempoolAcceptResult(package_state, {});
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}
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// Construct workspaces and check package policies.
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std::vector<Workspace> workspaces{};
1105-
workspaces.reserve(package_count);
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{
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std::unordered_set<uint256, SaltedTxidHasher> later_txids;
1108-
std::transform(txns.cbegin(), txns.cend(), std::inserter(later_txids, later_txids.end()),
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[](const auto& tx) { return tx->GetHash(); });
1110-
// Require the package to be sorted in order of dependency, i.e. parents appear before children.
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// An unsorted package will fail anyway on missing-inputs, but it's better to quit earlier and
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// fail on something less ambiguous (missing-inputs could also be an orphan or trying to
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// spend nonexistent coins).
1114-
for (const auto& tx : txns) {
1115-
for (const auto& input : tx->vin) {
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if (later_txids.find(input.prevout.hash) != later_txids.end()) {
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// The parent is a subsequent transaction in the package.
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package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-not-sorted");
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return PackageMempoolAcceptResult(package_state, {});
1120-
}
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}
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later_txids.erase(tx->GetHash());
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workspaces.emplace_back(Workspace(tx));
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}
1125-
}
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workspaces.reserve(txns.size());
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std::transform(txns.cbegin(), txns.cend(), std::back_inserter(workspaces),
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[](const auto& tx) { return Workspace(tx); });
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std::map<const uint256, const MempoolAcceptResult> results;
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{
1128-
// Don't allow any conflicting transactions, i.e. spending the same inputs, in a package.
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std::unordered_set<COutPoint, SaltedOutpointHasher> inputs_seen;
1130-
for (const auto& tx : txns) {
1131-
for (const auto& input : tx->vin) {
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if (inputs_seen.find(input.prevout) != inputs_seen.end()) {
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// This input is also present in another tx in the package.
1134-
package_state.Invalid(PackageValidationResult::PCKG_POLICY, "conflict-in-package");
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return PackageMempoolAcceptResult(package_state, {});
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}
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}
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// Batch-add all the inputs for a tx at a time. If we added them 1 at a time, we could
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// catch duplicate inputs within a single tx. This is a more severe, consensus error,
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// and we want to report that from CheckTransaction instead.
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std::transform(tx->vin.cbegin(), tx->vin.cend(), std::inserter(inputs_seen, inputs_seen.end()),
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[](const auto& input) { return input.prevout; });
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}
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}
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11461096
LOCK(m_pool.cs);
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