txvalidationcache_tests.cpp

// Copyright (c) 2011-2016 The Bitcoin Core developers
// Copyright (c) 2017 IoP Ventures LLC
// 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.h"
#include "validation.h"
#include "miner.h"
#include "pubkey.h"
#include "txmempool.h"
#include "random.h"
#include "script/standard.h"
#include "script/sign.h"
#include "test/test_iop.h"
#include "utiltime.h"
#include "core_io.h"
#include "keystore.h"
#include "policy/policy.h"

#include <boost/test/unit_test.hpp>

bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheSigStore, bool cacheFullScriptStore, PrecomputedTransactionData& txdata, std::vector<CScriptCheck> *pvChecks);

BOOST_AUTO_TEST_SUITE(tx_validationcache_tests)

static bool
ToMemPool(CMutableTransaction& tx)
{
    LOCK(cs_main);

    CValidationState state;
    return AcceptToMemoryPool(mempool, state, MakeTransactionRef(tx), false, nullptr, nullptr, true, 0);
}

BOOST_FIXTURE_TEST_CASE(tx_mempool_block_doublespend, TestChain100Setup)
{
    // Make sure skipping validation of transctions that were
    // validated going into the memory pool does not allow
    // double-spends in blocks to pass validation when they should not.

    CScript scriptPubKey = CScript() <<  ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;

    // Create a double-spend of mature coinbase txn:
    std::vector<CMutableTransaction> spends;
    spends.resize(2);
    for (int i = 0; i < 2; i++)
    {
        spends[i].nVersion = 1;
        spends[i].vin.resize(1);
        spends[i].vin[0].prevout.hash = coinbaseTxns[0].GetHash();
        spends[i].vin[0].prevout.n = 0;
        spends[i].vout.resize(1);
        spends[i].vout[0].nValue = 11*CENT;
        spends[i].vout[0].scriptPubKey = scriptPubKey;

        // Sign:
        std::vector<unsigned char> vchSig;
        uint256 hash = SignatureHash(scriptPubKey, spends[i], 0, SIGHASH_ALL, 0, SIGVERSION_BASE);
        BOOST_CHECK(coinbaseKey.Sign(hash, vchSig));
        vchSig.push_back((unsigned char)SIGHASH_ALL);
        spends[i].vin[0].scriptSig << vchSig;
    }

    CBlock block;

    // Test 1: block with both of those transactions should be rejected.
    block = CreateAndProcessBlock(spends, scriptPubKey);
    BOOST_CHECK(chainActive.Tip()->GetBlockHash() != block.GetHash());

    // Test 2: ... and should be rejected if spend1 is in the memory pool
    BOOST_CHECK(ToMemPool(spends[0]));
    block = CreateAndProcessBlock(spends, scriptPubKey);
    BOOST_CHECK(chainActive.Tip()->GetBlockHash() != block.GetHash());
    mempool.clear();

    // Test 3: ... and should be rejected if spend2 is in the memory pool
    BOOST_CHECK(ToMemPool(spends[1]));
    block = CreateAndProcessBlock(spends, scriptPubKey);
    BOOST_CHECK(chainActive.Tip()->GetBlockHash() != block.GetHash());
    mempool.clear();

    // Final sanity test: first spend in mempool, second in block, that's OK:
    std::vector<CMutableTransaction> oneSpend;
    oneSpend.push_back(spends[0]);
    BOOST_CHECK(ToMemPool(spends[1]));
    block = CreateAndProcessBlock(oneSpend, scriptPubKey);
    BOOST_CHECK(chainActive.Tip()->GetBlockHash() == block.GetHash());
    // spends[1] should have been removed from the mempool when the
    // block with spends[0] is accepted:
    BOOST_CHECK_EQUAL(mempool.size(), 0);
}

// Run CheckInputs (using pcoinsTip) on the given transaction, for all script
// flags.  Test that CheckInputs passes for all flags that don't overlap with
// the failing_flags argument, but otherwise fails.
// CHECKLOCKTIMEVERIFY and CHECKSEQUENCEVERIFY (and future NOP codes that may
// get reassigned) have an interaction with DISCOURAGE_UPGRADABLE_NOPS: if
// the script flags used contain DISCOURAGE_UPGRADABLE_NOPS but don't contain
// CHECKLOCKTIMEVERIFY (or CHECKSEQUENCEVERIFY), but the script does contain
// OP_CHECKLOCKTIMEVERIFY (or OP_CHECKSEQUENCEVERIFY), then script execution
// should fail.
// Capture this interaction with the upgraded_nop argument: set it when evaluating
// any script flag that is implemented as an upgraded NOP code.
void ValidateCheckInputsForAllFlags(CMutableTransaction &tx, uint32_t failing_flags, bool add_to_cache, bool upgraded_nop)
{
    PrecomputedTransactionData txdata(tx);
    // If we add many more flags, this loop can get too expensive, but we can
    // rewrite in the future to randomly pick a set of flags to evaluate.
    for (uint32_t test_flags=0; test_flags < (1U << 16); test_flags += 1) {
        CValidationState state;
        // Filter out incompatible flag choices
        if ((test_flags & SCRIPT_VERIFY_CLEANSTACK)) {
            // CLEANSTACK requires P2SH and WITNESS, see VerifyScript() in
            // script/interpreter.cpp
            test_flags |= SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS;
        }
        if ((test_flags & SCRIPT_VERIFY_WITNESS)) {
            // WITNESS requires P2SH
            test_flags |= SCRIPT_VERIFY_P2SH;
        }
        bool ret = CheckInputs(tx, state, pcoinsTip, true, test_flags, true, add_to_cache, txdata, nullptr);
        // CheckInputs should succeed iff test_flags doesn't intersect with
        // failing_flags
        bool expected_return_value = !(test_flags & failing_flags);
        if (expected_return_value && upgraded_nop) {
            // If the script flag being tested corresponds to an upgraded NOP,
            // then script execution should fail if DISCOURAGE_UPGRADABLE_NOPS
            // is set.
            expected_return_value = !(test_flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS);
        }
        BOOST_CHECK_EQUAL(ret, expected_return_value);

        // Test the caching
        if (ret && add_to_cache) {
            // Check that we get a cache hit if the tx was valid
            std::vector<CScriptCheck> scriptchecks;
            BOOST_CHECK(CheckInputs(tx, state, pcoinsTip, true, test_flags, true, add_to_cache, txdata, &scriptchecks));
            BOOST_CHECK(scriptchecks.empty());
        } else {
            // Check that we get script executions to check, if the transaction
            // was invalid, or we didn't add to cache.
            std::vector<CScriptCheck> scriptchecks;
            BOOST_CHECK(CheckInputs(tx, state, pcoinsTip, true, test_flags, true, add_to_cache, txdata, &scriptchecks));
            BOOST_CHECK_EQUAL(scriptchecks.size(), tx.vin.size());
        }
    }
}

// TODO: Reimplement this for IOP
// BOOST_FIXTURE_TEST_CASE(checkinputs_test, TestChain100Setup)
// {
//     // Test that passing CheckInputs with one set of script flags doesn't imply
//     // that we would pass again with a different set of flags.
//     InitScriptExecutionCache();

//     CScript p2pk_scriptPubKey = CScript() << ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;
//     CScript p2sh_scriptPubKey = GetScriptForDestination(CScriptID(p2pk_scriptPubKey));
//     CScript p2pkh_scriptPubKey = GetScriptForDestination(coinbaseKey.GetPubKey().GetID());
//     CScript p2wpkh_scriptPubKey = GetScriptForWitness(p2pkh_scriptPubKey);

//     CBasicKeyStore keystore;
//     keystore.AddKey(coinbaseKey);
//     keystore.AddCScript(p2pk_scriptPubKey);

//     // flags to test: SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY, SCRIPT_VERIFY_CHECKSEQUENCE_VERIFY, SCRIPT_VERIFY_NULLDUMMY, uncompressed pubkey thing

//     // Create 2 outputs that match the three scripts above, spending the first
//     // coinbase tx.
//     CMutableTransaction spend_tx;

//     spend_tx.nVersion = 1;
//     spend_tx.vin.resize(1);
//     spend_tx.vin[0].prevout.hash = coinbaseTxns[0].GetHash();
//     spend_tx.vin[0].prevout.n = 0;
//     spend_tx.vout.resize(4);
//     spend_tx.vout[0].nValue = 11*CENT;
//     spend_tx.vout[0].scriptPubKey = p2sh_scriptPubKey;
//     spend_tx.vout[1].nValue = 11*CENT;
//     spend_tx.vout[1].scriptPubKey = p2wpkh_scriptPubKey;
//     spend_tx.vout[2].nValue = 11*CENT;
//     spend_tx.vout[2].scriptPubKey = CScript() << OP_CHECKLOCKTIMEVERIFY << OP_DROP << ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;
//     spend_tx.vout[3].nValue = 11*CENT;
//     spend_tx.vout[3].scriptPubKey = CScript() << OP_CHECKSEQUENCEVERIFY << OP_DROP << ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;

//     // Sign, with a non-DER signature
//     {
//         std::vector<unsigned char> vchSig;
//         uint256 hash = SignatureHash(p2pk_scriptPubKey, spend_tx, 0, SIGHASH_ALL, 0, SIGVERSION_BASE);
//         BOOST_CHECK(coinbaseKey.Sign(hash, vchSig));
//         vchSig.push_back((unsigned char) 0); // padding byte makes this non-DER
//         vchSig.push_back((unsigned char)SIGHASH_ALL);
//         spend_tx.vin[0].scriptSig << vchSig;
//     }

//     LOCK(cs_main);

//     // Test that invalidity under a set of flags doesn't preclude validity
//     // under other (eg consensus) flags.
//     // spend_tx is invalid according to DERSIG
//     {
//         CValidationState state;
//         PrecomputedTransactionData ptd_spend_tx(spend_tx);

//         BOOST_CHECK(!CheckInputs(spend_tx, state, pcoinsTip, true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_DERSIG, true, true, ptd_spend_tx, nullptr));

//         // If we call again asking for scriptchecks (as happens in
//         // ConnectBlock), we should add a script check object for this -- we're
//         // not caching invalidity (if that changes, delete this test case).
//         std::vector<CScriptCheck> scriptchecks;
//         BOOST_CHECK(CheckInputs(spend_tx, state, pcoinsTip, true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_DERSIG, true, true, ptd_spend_tx, &scriptchecks));
//         BOOST_CHECK_EQUAL(scriptchecks.size(), 1);

//         // Test that CheckInputs returns true iff DERSIG-enforcing flags are
//         // not present.  Don't add these checks to the cache, so that we can
//         // test later that block validation works fine in the absence of cached
//         // successes.
//         ValidateCheckInputsForAllFlags(spend_tx, SCRIPT_VERIFY_DERSIG | SCRIPT_VERIFY_LOW_S | SCRIPT_VERIFY_STRICTENC, false, false);

//         // And if we produce a block with this tx, it should be valid (DERSIG not
//         // enabled yet), even though there's no cache entry.
//         CBlock block;

//         block = CreateAndProcessBlock({spend_tx}, p2pk_scriptPubKey);
//         BOOST_CHECK(chainActive.Tip()->GetBlockHash() == block.GetHash());
//         BOOST_CHECK(pcoinsTip->GetBestBlock() == block.GetHash());
//     }

//     // Test P2SH: construct a transaction that is valid without P2SH, and
//     // then test validity with P2SH.
//     {
//         CMutableTransaction invalid_under_p2sh_tx;
//         invalid_under_p2sh_tx.nVersion = 1;
//         invalid_under_p2sh_tx.vin.resize(1);
//         invalid_under_p2sh_tx.vin[0].prevout.hash = spend_tx.GetHash();
//         invalid_under_p2sh_tx.vin[0].prevout.n = 0;
//         invalid_under_p2sh_tx.vout.resize(1);
//         invalid_under_p2sh_tx.vout[0].nValue = 11*CENT;
//         invalid_under_p2sh_tx.vout[0].scriptPubKey = p2pk_scriptPubKey;
//         std::vector<unsigned char> vchSig2(p2pk_scriptPubKey.begin(), p2pk_scriptPubKey.end());
//         invalid_under_p2sh_tx.vin[0].scriptSig << vchSig2;

//         ValidateCheckInputsForAllFlags(invalid_under_p2sh_tx, SCRIPT_VERIFY_P2SH, true, false);
//     }

//     // Test CHECKLOCKTIMEVERIFY
//     {
//         CMutableTransaction invalid_with_cltv_tx;
//         invalid_with_cltv_tx.nVersion = 1;
//         invalid_with_cltv_tx.nLockTime = 100;
//         invalid_with_cltv_tx.vin.resize(1);
//         invalid_with_cltv_tx.vin[0].prevout.hash = spend_tx.GetHash();
//         invalid_with_cltv_tx.vin[0].prevout.n = 2;
//         invalid_with_cltv_tx.vin[0].nSequence = 0;
//         invalid_with_cltv_tx.vout.resize(1);
//         invalid_with_cltv_tx.vout[0].nValue = 11*CENT;
//         invalid_with_cltv_tx.vout[0].scriptPubKey = p2pk_scriptPubKey;

//         // Sign
//         std::vector<unsigned char> vchSig;
//         uint256 hash = SignatureHash(spend_tx.vout[2].scriptPubKey, invalid_with_cltv_tx, 0, SIGHASH_ALL, 0, SIGVERSION_BASE);
//         BOOST_CHECK(coinbaseKey.Sign(hash, vchSig));
//         vchSig.push_back((unsigned char)SIGHASH_ALL);
//         invalid_with_cltv_tx.vin[0].scriptSig = CScript() << vchSig << 101;

//         ValidateCheckInputsForAllFlags(invalid_with_cltv_tx, SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY, true, true);

//         // Make it valid, and check again
//         invalid_with_cltv_tx.vin[0].scriptSig = CScript() << vchSig << 100;
//         CValidationState state;
//         PrecomputedTransactionData txdata(invalid_with_cltv_tx);
//         BOOST_CHECK(CheckInputs(invalid_with_cltv_tx, state, pcoinsTip, true, SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY, true, true, txdata, nullptr));
//     }

//     // TEST CHECKSEQUENCEVERIFY
//     {
//         CMutableTransaction invalid_with_csv_tx;
//         invalid_with_csv_tx.nVersion = 2;
//         invalid_with_csv_tx.vin.resize(1);
//         invalid_with_csv_tx.vin[0].prevout.hash = spend_tx.GetHash();
//         invalid_with_csv_tx.vin[0].prevout.n = 3;
//         invalid_with_csv_tx.vin[0].nSequence = 100;
//         invalid_with_csv_tx.vout.resize(1);
//         invalid_with_csv_tx.vout[0].nValue = 11*CENT;
//         invalid_with_csv_tx.vout[0].scriptPubKey = p2pk_scriptPubKey;

//         // Sign
//         std::vector<unsigned char> vchSig;
//         uint256 hash = SignatureHash(spend_tx.vout[3].scriptPubKey, invalid_with_csv_tx, 0, SIGHASH_ALL, 0, SIGVERSION_BASE);
//         BOOST_CHECK(coinbaseKey.Sign(hash, vchSig));
//         vchSig.push_back((unsigned char)SIGHASH_ALL);
//         invalid_with_csv_tx.vin[0].scriptSig = CScript() << vchSig << 101;

//         ValidateCheckInputsForAllFlags(invalid_with_csv_tx, SCRIPT_VERIFY_CHECKSEQUENCEVERIFY, true, true);

//         // Make it valid, and check again
//         invalid_with_csv_tx.vin[0].scriptSig = CScript() << vchSig << 100;
//         CValidationState state;
//         PrecomputedTransactionData txdata(invalid_with_csv_tx);
//         BOOST_CHECK(CheckInputs(invalid_with_csv_tx, state, pcoinsTip, true, SCRIPT_VERIFY_CHECKSEQUENCEVERIFY, true, true, txdata, nullptr));
//     }

//     // TODO: add tests for remaining script flags

//     // Test that passing CheckInputs with a valid witness doesn't imply success
//     // for the same tx with a different witness.
//     {
//         CMutableTransaction valid_with_witness_tx;
//         valid_with_witness_tx.nVersion = 1;
//         valid_with_witness_tx.vin.resize(1);
//         valid_with_witness_tx.vin[0].prevout.hash = spend_tx.GetHash();
//         valid_with_witness_tx.vin[0].prevout.n = 1;
//         valid_with_witness_tx.vout.resize(1);
//         valid_with_witness_tx.vout[0].nValue = 11*CENT;
//         valid_with_witness_tx.vout[0].scriptPubKey = p2pk_scriptPubKey;

//         // Sign
//         SignatureData sigdata;
//         ProduceSignature(MutableTransactionSignatureCreator(&keystore, &valid_with_witness_tx, 0, 11*CENT, SIGHASH_ALL), spend_tx.vout[1].scriptPubKey, sigdata);
//         UpdateTransaction(valid_with_witness_tx, 0, sigdata);

//         // This should be valid under all script flags.
//         ValidateCheckInputsForAllFlags(valid_with_witness_tx, 0, true, false);

//         // Remove the witness, and check that it is now invalid.
//         valid_with_witness_tx.vin[0].scriptWitness.SetNull();
//         ValidateCheckInputsForAllFlags(valid_with_witness_tx, SCRIPT_VERIFY_WITNESS, true, false);
//     }

//     {
//         // Test a transaction with multiple inputs.
//         CMutableTransaction tx;

//         tx.nVersion = 1;
//         tx.vin.resize(2);
//         tx.vin[0].prevout.hash = spend_tx.GetHash();
//         tx.vin[0].prevout.n = 0;
//         tx.vin[1].prevout.hash = spend_tx.GetHash();
//         tx.vin[1].prevout.n = 1;
//         tx.vout.resize(1);
//         tx.vout[0].nValue = 22*CENT;
//         tx.vout[0].scriptPubKey = p2pk_scriptPubKey;

//         // Sign
//         for (int i=0; i<2; ++i) {
//             SignatureData sigdata;
//             ProduceSignature(MutableTransactionSignatureCreator(&keystore, &tx, i, 11*CENT, SIGHASH_ALL), spend_tx.vout[i].scriptPubKey, sigdata);
//             UpdateTransaction(tx, i, sigdata);
//         }

//         // This should be valid under all script flags
//         ValidateCheckInputsForAllFlags(tx, 0, true, false);

//         // Check that if the second input is invalid, but the first input is
//         // valid, the transaction is not cached.
//         // Invalidate vin[1]
//         tx.vin[1].scriptWitness.SetNull();

//         CValidationState state;
//         PrecomputedTransactionData txdata(tx);
//         // This transaction is now invalid under segwit, because of the second input.
//         BOOST_CHECK(!CheckInputs(tx, state, pcoinsTip, true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS, true, true, txdata, nullptr));

//         std::vector<CScriptCheck> scriptchecks;
//         // Make sure this transaction was not cached (ie because the first
//         // input was valid)
//         BOOST_CHECK(CheckInputs(tx, state, pcoinsTip, true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS, true, true, txdata, &scriptchecks));
//         // Should get 2 script checks back -- caching is on a whole-transaction basis.
//         BOOST_CHECK_EQUAL(scriptchecks.size(), 2);
//     }
// }

BOOST_AUTO_TEST_SUITE_END()