// Copyright (c) 2015-2022 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 #include #include #include #include #include #include BOOST_FIXTURE_TEST_SUITE(pow_tests, BasicTestingSetup) /* Test calculation of next difficulty target with no constraints applying */ BOOST_AUTO_TEST_CASE(get_next_work) { const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); int64_t nLastRetargetTime = 1261130161; // Block #30240 CBlockIndex pindexLast; pindexLast.nHeight = 32255; pindexLast.nTime = 1262152739; // Block #32255 pindexLast.nBits = 0x1d00ffff; // Here (and below): expected_nbits is calculated in // CalculateNextWorkRequired(); redoing the calculation here would be just // reimplementing the same code that is written in pow.cpp. Rather than // copy that code, we just hardcode the expected result. unsigned int expected_nbits = 0x1d00d86aU; BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); } /* Test the constraint on the upper bound for next work */ BOOST_AUTO_TEST_CASE(get_next_work_pow_limit) { const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); int64_t nLastRetargetTime = 1231006505; // Block #0 CBlockIndex pindexLast; pindexLast.nHeight = 2015; pindexLast.nTime = 1233061996; // Block #2015 pindexLast.nBits = 0x1d00ffff; unsigned int expected_nbits = 0x1d00ffffU; BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); } /* Test the constraint on the lower bound for actual time taken */ BOOST_AUTO_TEST_CASE(get_next_work_lower_limit_actual) { const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); int64_t nLastRetargetTime = 1279008237; // Block #66528 CBlockIndex pindexLast; pindexLast.nHeight = 68543; pindexLast.nTime = 1279297671; // Block #68543 pindexLast.nBits = 0x1c05a3f4; unsigned int expected_nbits = 0x1c0168fdU; BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); // Test that reducing nbits further would not be a PermittedDifficultyTransition. unsigned int invalid_nbits = expected_nbits-1; BOOST_CHECK(!PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, invalid_nbits)); } /* Test the constraint on the upper bound for actual time taken */ BOOST_AUTO_TEST_CASE(get_next_work_upper_limit_actual) { const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); int64_t nLastRetargetTime = 1263163443; // NOTE: Not an actual block time CBlockIndex pindexLast; pindexLast.nHeight = 46367; pindexLast.nTime = 1269211443; // Block #46367 pindexLast.nBits = 0x1c387f6f; unsigned int expected_nbits = 0x1d00e1fdU; BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); // Test that increasing nbits further would not be a PermittedDifficultyTransition. unsigned int invalid_nbits = expected_nbits+1; BOOST_CHECK(!PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, invalid_nbits)); } BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_negative_target) { const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); uint256 hash; unsigned int nBits; nBits = UintToArith256(consensus.powLimit).GetCompact(true); hash = uint256{1}; BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); } BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_overflow_target) { const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); uint256 hash; unsigned int nBits{~0x00800000U}; hash = uint256{1}; BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); } BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_too_easy_target) { const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); uint256 hash; unsigned int nBits; arith_uint256 nBits_arith = UintToArith256(consensus.powLimit); nBits_arith *= 2; nBits = nBits_arith.GetCompact(); hash = uint256{1}; BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); } BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_biger_hash_than_target) { const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); uint256 hash; unsigned int nBits; arith_uint256 hash_arith = UintToArith256(consensus.powLimit); nBits = hash_arith.GetCompact(); hash_arith *= 2; // hash > nBits hash = ArithToUint256(hash_arith); BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); } BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_zero_target) { const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); uint256 hash; unsigned int nBits; arith_uint256 hash_arith{0}; nBits = hash_arith.GetCompact(); hash = ArithToUint256(hash_arith); BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); } BOOST_AUTO_TEST_CASE(GetBlockProofEquivalentTime_test) { const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); std::vector blocks(10000); for (int i = 0; i < 10000; i++) { blocks[i].pprev = i ? &blocks[i - 1] : nullptr; blocks[i].nHeight = i; blocks[i].nTime = 1269211443 + i * chainParams->GetConsensus().nPowTargetSpacing; blocks[i].nBits = 0x207fffff; /* target 0x7fffff000... */ blocks[i].nChainWork = i ? blocks[i - 1].nChainWork + GetBlockProof(blocks[i - 1]) : arith_uint256(0); } for (int j = 0; j < 1000; j++) { CBlockIndex *p1 = &blocks[InsecureRandRange(10000)]; CBlockIndex *p2 = &blocks[InsecureRandRange(10000)]; CBlockIndex *p3 = &blocks[InsecureRandRange(10000)]; int64_t tdiff = GetBlockProofEquivalentTime(*p1, *p2, *p3, chainParams->GetConsensus()); BOOST_CHECK_EQUAL(tdiff, p1->GetBlockTime() - p2->GetBlockTime()); } } void sanity_check_chainparams(const ArgsManager& args, ChainType chain_type) { const auto chainParams = CreateChainParams(args, chain_type); const auto consensus = chainParams->GetConsensus(); // hash genesis is correct BOOST_CHECK_EQUAL(consensus.hashGenesisBlock, chainParams->GenesisBlock().GetHash()); // target timespan is an even multiple of spacing BOOST_CHECK_EQUAL(consensus.nPowTargetTimespan % consensus.nPowTargetSpacing, 0); // genesis nBits is positive, doesn't overflow and is lower than powLimit arith_uint256 pow_compact; bool neg, over; pow_compact.SetCompact(chainParams->GenesisBlock().nBits, &neg, &over); BOOST_CHECK(!neg && pow_compact != 0); BOOST_CHECK(!over); BOOST_CHECK(UintToArith256(consensus.powLimit) >= pow_compact); // check max target * 4*nPowTargetTimespan doesn't overflow -- see pow.cpp:CalculateNextWorkRequired() if (!consensus.fPowNoRetargeting) { arith_uint256 targ_max{UintToArith256(uint256{"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"})}; targ_max /= consensus.nPowTargetTimespan*4; BOOST_CHECK(UintToArith256(consensus.powLimit) < targ_max); } } BOOST_AUTO_TEST_CASE(ChainParams_MAIN_sanity) { sanity_check_chainparams(*m_node.args, ChainType::MAIN); } BOOST_AUTO_TEST_CASE(ChainParams_REGTEST_sanity) { sanity_check_chainparams(*m_node.args, ChainType::REGTEST); } BOOST_AUTO_TEST_CASE(ChainParams_TESTNET_sanity) { sanity_check_chainparams(*m_node.args, ChainType::TESTNET); } BOOST_AUTO_TEST_CASE(ChainParams_TESTNET4_sanity) { sanity_check_chainparams(*m_node.args, ChainType::TESTNET4); } BOOST_AUTO_TEST_CASE(ChainParams_SIGNET_sanity) { sanity_check_chainparams(*m_node.args, ChainType::SIGNET); } BOOST_AUTO_TEST_SUITE_END()