bitcoin-bitcoin-core/src/test/txpackage_tests.cpp

// Copyright (c) 2021 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <consensus/validation.h>
#include <key_io.h>
#include <policy/packages.h>
#include <policy/policy.h>
#include <primitives/transaction.h>
#include <script/script.h>
#include <script/standard.h>
#include <test/util/setup_common.h>
#include <validation.h>

#include <boost/test/unit_test.hpp>

BOOST_AUTO_TEST_SUITE(txpackage_tests)

// Create placeholder transactions that have no meaning.
inline CTransactionRef create_placeholder_tx(size_t num_inputs, size_t num_outputs)
{
    CMutableTransaction mtx = CMutableTransaction();
    mtx.vin.resize(num_inputs);
    mtx.vout.resize(num_outputs);
    auto random_script = CScript() << ToByteVector(InsecureRand256()) << ToByteVector(InsecureRand256());
    for (size_t i{0}; i < num_inputs; ++i) {
        mtx.vin[i].prevout.hash = InsecureRand256();
        mtx.vin[i].prevout.n = 0;
        mtx.vin[i].scriptSig = random_script;
    }
    for (size_t o{0}; o < num_outputs; ++o) {
        mtx.vout[o].nValue = 1 * CENT;
        mtx.vout[o].scriptPubKey = random_script;
    }
    return MakeTransactionRef(mtx);
}

BOOST_FIXTURE_TEST_CASE(package_sanitization_tests, TestChain100Setup)
{
    // Packages can't have more than 25 transactions.
    Package package_too_many;
    package_too_many.reserve(MAX_PACKAGE_COUNT + 1);
    for (size_t i{0}; i < MAX_PACKAGE_COUNT + 1; ++i) {
        package_too_many.emplace_back(create_placeholder_tx(1, 1));
    }
    PackageValidationState state_too_many;
    BOOST_CHECK(!CheckPackage(package_too_many, state_too_many));
    BOOST_CHECK_EQUAL(state_too_many.GetResult(), PackageValidationResult::PCKG_POLICY);
    BOOST_CHECK_EQUAL(state_too_many.GetRejectReason(), "package-too-many-transactions");

    // Packages can't have a total size of more than 101KvB.
    CTransactionRef large_ptx = create_placeholder_tx(150, 150);
    Package package_too_large;
    auto size_large = GetVirtualTransactionSize(*large_ptx);
    size_t total_size{0};
    while (total_size <= MAX_PACKAGE_SIZE * 1000) {
        package_too_large.push_back(large_ptx);
        total_size += size_large;
    }
    BOOST_CHECK(package_too_large.size() <= MAX_PACKAGE_COUNT);
    PackageValidationState state_too_large;
    BOOST_CHECK(!CheckPackage(package_too_large, state_too_large));
    BOOST_CHECK_EQUAL(state_too_large.GetResult(), PackageValidationResult::PCKG_POLICY);
    BOOST_CHECK_EQUAL(state_too_large.GetRejectReason(), "package-too-large");
}

BOOST_FIXTURE_TEST_CASE(package_validation_tests, TestChain100Setup)
{
    LOCK(cs_main);
    unsigned int initialPoolSize = m_node.mempool->size();

    // Parent and Child Package
    CKey parent_key;
    parent_key.MakeNewKey(true);
    CScript parent_locking_script = GetScriptForDestination(PKHash(parent_key.GetPubKey()));
    auto mtx_parent = CreateValidMempoolTransaction(/* input_transaction */ m_coinbase_txns[0], /* vout */ 0,
                                                    /* input_height */ 0, /* input_signing_key */ coinbaseKey,
                                                    /* output_destination */ parent_locking_script,
                                                    /* output_amount */ CAmount(49 * COIN), /* submit */ false);
    CTransactionRef tx_parent = MakeTransactionRef(mtx_parent);

    CKey child_key;
    child_key.MakeNewKey(true);
    CScript child_locking_script = GetScriptForDestination(PKHash(child_key.GetPubKey()));
    auto mtx_child = CreateValidMempoolTransaction(/* input_transaction */ tx_parent, /* vout */ 0,
                                                   /* input_height */ 101, /* input_signing_key */ parent_key,
                                                   /* output_destination */ child_locking_script,
                                                   /* output_amount */ CAmount(48 * COIN), /* submit */ false);
    CTransactionRef tx_child = MakeTransactionRef(mtx_child);
    const auto result_parent_child = ProcessNewPackage(m_node.chainman->ActiveChainstate(), *m_node.mempool, {tx_parent, tx_child}, /* test_accept */ true);
    BOOST_CHECK_MESSAGE(result_parent_child.m_state.IsValid(),
                        "Package validation unexpectedly failed: " << result_parent_child.m_state.GetRejectReason());
    auto it_parent = result_parent_child.m_tx_results.find(tx_parent->GetWitnessHash());
    auto it_child = result_parent_child.m_tx_results.find(tx_child->GetWitnessHash());
    BOOST_CHECK(it_parent != result_parent_child.m_tx_results.end());
    BOOST_CHECK_MESSAGE(it_parent->second.m_state.IsValid(),
                        "Package validation unexpectedly failed: " << it_parent->second.m_state.GetRejectReason());
    BOOST_CHECK(it_child != result_parent_child.m_tx_results.end());
    BOOST_CHECK_MESSAGE(it_child->second.m_state.IsValid(),
                        "Package validation unexpectedly failed: " << it_child->second.m_state.GetRejectReason());


    // A single, giant transaction submitted through ProcessNewPackage fails on single tx policy.
    CTransactionRef giant_ptx = create_placeholder_tx(999, 999);
    BOOST_CHECK(GetVirtualTransactionSize(*giant_ptx) > MAX_PACKAGE_SIZE * 1000);
    auto result_single_large = ProcessNewPackage(m_node.chainman->ActiveChainstate(), *m_node.mempool, {giant_ptx}, /* test_accept */ true);
    BOOST_CHECK(result_single_large.m_state.IsInvalid());
    BOOST_CHECK_EQUAL(result_single_large.m_state.GetResult(), PackageValidationResult::PCKG_TX);
    BOOST_CHECK_EQUAL(result_single_large.m_state.GetRejectReason(), "transaction failed");
    auto it_giant_tx = result_single_large.m_tx_results.find(giant_ptx->GetWitnessHash());
    BOOST_CHECK(it_giant_tx != result_single_large.m_tx_results.end());
    BOOST_CHECK_EQUAL(it_giant_tx->second.m_state.GetRejectReason(), "tx-size");

    // Check that mempool size hasn't changed.
    BOOST_CHECK_EQUAL(m_node.mempool->size(), initialPoolSize);
}

BOOST_FIXTURE_TEST_CASE(noncontextual_package_tests, TestChain100Setup)
{
    // The signatures won't be verified so we can just use a placeholder
    CKey placeholder_key;
    placeholder_key.MakeNewKey(true);
    CScript spk = GetScriptForDestination(PKHash(placeholder_key.GetPubKey()));
    CKey placeholder_key_2;
    placeholder_key_2.MakeNewKey(true);
    CScript spk2 = GetScriptForDestination(PKHash(placeholder_key_2.GetPubKey()));

    // Parent and Child Package
    {
        auto mtx_parent = CreateValidMempoolTransaction(m_coinbase_txns[0], 0, 0, coinbaseKey, spk,
                                                        CAmount(49 * COIN), /* submit */ false);
        CTransactionRef tx_parent = MakeTransactionRef(mtx_parent);

        auto mtx_child = CreateValidMempoolTransaction(tx_parent, 0, 101, placeholder_key, spk2,
                                                       CAmount(48 * COIN), /* submit */ false);
        CTransactionRef tx_child = MakeTransactionRef(mtx_child);

        PackageValidationState state;
        BOOST_CHECK(CheckPackage({tx_parent, tx_child}, state));
        BOOST_CHECK(!CheckPackage({tx_child, tx_parent}, state));
        BOOST_CHECK_EQUAL(state.GetResult(), PackageValidationResult::PCKG_POLICY);
        BOOST_CHECK_EQUAL(state.GetRejectReason(), "package-not-sorted");
        BOOST_CHECK(IsChildWithParents({tx_parent, tx_child}));
    }

    // 24 Parents and 1 Child
    {
        Package package;
        CMutableTransaction child;
        for (int i{0}; i < 24; ++i) {
            auto parent = MakeTransactionRef(CreateValidMempoolTransaction(m_coinbase_txns[i + 1],
                                             0, 0, coinbaseKey, spk, CAmount(48 * COIN), false));
            package.emplace_back(parent);
            child.vin.push_back(CTxIn(COutPoint(parent->GetHash(), 0)));
        }
        child.vout.push_back(CTxOut(47 * COIN, spk2));

        // The child must be in the package.
        BOOST_CHECK(!IsChildWithParents(package));

        // The parents can be in any order.
        FastRandomContext rng;
        Shuffle(package.begin(), package.end(), rng);
        package.push_back(MakeTransactionRef(child));

        PackageValidationState state;
        BOOST_CHECK(CheckPackage(package, state));
        BOOST_CHECK(IsChildWithParents(package));

        package.erase(package.begin());
        BOOST_CHECK(IsChildWithParents(package));

        // The package cannot have unrelated transactions.
        package.insert(package.begin(), m_coinbase_txns[0]);
        BOOST_CHECK(!IsChildWithParents(package));
    }

    // 2 Parents and 1 Child where one parent depends on the other.
    {
        CMutableTransaction mtx_parent;
        mtx_parent.vin.push_back(CTxIn(COutPoint(m_coinbase_txns[0]->GetHash(), 0)));
        mtx_parent.vout.push_back(CTxOut(20 * COIN, spk));
        mtx_parent.vout.push_back(CTxOut(20 * COIN, spk2));
        CTransactionRef tx_parent = MakeTransactionRef(mtx_parent);

        CMutableTransaction mtx_parent_also_child;
        mtx_parent_also_child.vin.push_back(CTxIn(COutPoint(tx_parent->GetHash(), 0)));
        mtx_parent_also_child.vout.push_back(CTxOut(20 * COIN, spk));
        CTransactionRef tx_parent_also_child = MakeTransactionRef(mtx_parent_also_child);

        CMutableTransaction mtx_child;
        mtx_child.vin.push_back(CTxIn(COutPoint(tx_parent->GetHash(), 1)));
        mtx_child.vin.push_back(CTxIn(COutPoint(tx_parent_also_child->GetHash(), 0)));
        mtx_child.vout.push_back(CTxOut(39 * COIN, spk));
        CTransactionRef tx_child = MakeTransactionRef(mtx_child);

        PackageValidationState state;
        BOOST_CHECK(IsChildWithParents({tx_parent, tx_parent_also_child}));
        BOOST_CHECK(IsChildWithParents({tx_parent, tx_child}));
        BOOST_CHECK(IsChildWithParents({tx_parent, tx_parent_also_child, tx_child}));
        // IsChildWithParents does not detect unsorted parents.
        BOOST_CHECK(IsChildWithParents({tx_parent_also_child, tx_parent, tx_child}));
        BOOST_CHECK(CheckPackage({tx_parent, tx_parent_also_child, tx_child}, state));
        BOOST_CHECK(!CheckPackage({tx_parent_also_child, tx_parent, tx_child}, state));
        BOOST_CHECK_EQUAL(state.GetResult(), PackageValidationResult::PCKG_POLICY);
        BOOST_CHECK_EQUAL(state.GetRejectReason(), "package-not-sorted");
    }
}

BOOST_AUTO_TEST_SUITE_END()