pow_tests.cpp
1 // Copyright (c) 2015-present The Bitcoin Core developers 2 // Distributed under the MIT software license, see the accompanying 3 // file COPYING or http://www.opensource.org/licenses/mit-license.php. 4 5 #include <chain.h> 6 #include <chainparams.h> 7 #include <pow.h> 8 #include <test/util/random.h> 9 #include <test/util/common.h> 10 #include <test/util/setup_common.h> 11 #include <util/chaintype.h> 12 13 #include <boost/test/unit_test.hpp> 14 15 BOOST_FIXTURE_TEST_SUITE(pow_tests, BasicTestingSetup) 16 17 /* Test calculation of next difficulty target with no constraints applying */ 18 BOOST_AUTO_TEST_CASE(get_next_work) 19 { 20 const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); 21 int64_t nLastRetargetTime = 1261130161; // Block #30240 22 CBlockIndex pindexLast; 23 pindexLast.nHeight = 32255; 24 pindexLast.nTime = 1262152739; // Block #32255 25 pindexLast.nBits = 0x1d00ffff; 26 27 // Here (and below): expected_nbits is calculated in 28 // CalculateNextWorkRequired(); redoing the calculation here would be just 29 // reimplementing the same code that is written in pow.cpp. Rather than 30 // copy that code, we just hardcode the expected result. 31 unsigned int expected_nbits = 0x1d00d86aU; 32 BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); 33 BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); 34 } 35 36 /* Test the constraint on the upper bound for next work */ 37 BOOST_AUTO_TEST_CASE(get_next_work_pow_limit) 38 { 39 const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); 40 int64_t nLastRetargetTime = 1231006505; // Block #0 41 CBlockIndex pindexLast; 42 pindexLast.nHeight = 2015; 43 pindexLast.nTime = 1233061996; // Block #2015 44 pindexLast.nBits = 0x1d00ffff; 45 unsigned int expected_nbits = 0x1d00ffffU; 46 BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); 47 BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); 48 } 49 50 /* Test the constraint on the lower bound for actual time taken */ 51 BOOST_AUTO_TEST_CASE(get_next_work_lower_limit_actual) 52 { 53 const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); 54 int64_t nLastRetargetTime = 1279008237; // Block #66528 55 CBlockIndex pindexLast; 56 pindexLast.nHeight = 68543; 57 pindexLast.nTime = 1279297671; // Block #68543 58 pindexLast.nBits = 0x1c05a3f4; 59 unsigned int expected_nbits = 0x1c0168fdU; 60 BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); 61 BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); 62 // Test that reducing nbits further would not be a PermittedDifficultyTransition. 63 unsigned int invalid_nbits = expected_nbits-1; 64 BOOST_CHECK(!PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, invalid_nbits)); 65 } 66 67 /* Test the constraint on the upper bound for actual time taken */ 68 BOOST_AUTO_TEST_CASE(get_next_work_upper_limit_actual) 69 { 70 const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); 71 int64_t nLastRetargetTime = 1263163443; // NOTE: Not an actual block time 72 CBlockIndex pindexLast; 73 pindexLast.nHeight = 46367; 74 pindexLast.nTime = 1269211443; // Block #46367 75 pindexLast.nBits = 0x1c387f6f; 76 unsigned int expected_nbits = 0x1d00e1fdU; 77 BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime, chainParams->GetConsensus()), expected_nbits); 78 BOOST_CHECK(PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, expected_nbits)); 79 // Test that increasing nbits further would not be a PermittedDifficultyTransition. 80 unsigned int invalid_nbits = expected_nbits+1; 81 BOOST_CHECK(!PermittedDifficultyTransition(chainParams->GetConsensus(), pindexLast.nHeight+1, pindexLast.nBits, invalid_nbits)); 82 } 83 84 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_negative_target) 85 { 86 const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); 87 uint256 hash; 88 unsigned int nBits; 89 nBits = UintToArith256(consensus.powLimit).GetCompact(true); 90 hash = uint256{1}; 91 BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); 92 } 93 94 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_overflow_target) 95 { 96 const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); 97 uint256 hash; 98 unsigned int nBits{~0x00800000U}; 99 hash = uint256{1}; 100 BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); 101 } 102 103 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_too_easy_target) 104 { 105 const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); 106 uint256 hash; 107 unsigned int nBits; 108 arith_uint256 nBits_arith = UintToArith256(consensus.powLimit); 109 nBits_arith *= 2; 110 nBits = nBits_arith.GetCompact(); 111 hash = uint256{1}; 112 BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); 113 } 114 115 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_biger_hash_than_target) 116 { 117 const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); 118 uint256 hash; 119 unsigned int nBits; 120 arith_uint256 hash_arith = UintToArith256(consensus.powLimit); 121 nBits = hash_arith.GetCompact(); 122 hash_arith *= 2; // hash > nBits 123 hash = ArithToUint256(hash_arith); 124 BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); 125 } 126 127 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_zero_target) 128 { 129 const auto consensus = CreateChainParams(*m_node.args, ChainType::MAIN)->GetConsensus(); 130 uint256 hash; 131 unsigned int nBits; 132 arith_uint256 hash_arith{0}; 133 nBits = hash_arith.GetCompact(); 134 hash = ArithToUint256(hash_arith); 135 BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus)); 136 } 137 138 BOOST_AUTO_TEST_CASE(GetBlockProofEquivalentTime_test) 139 { 140 const auto chainParams = CreateChainParams(*m_node.args, ChainType::MAIN); 141 std::vector<CBlockIndex> blocks(10000); 142 for (int i = 0; i < 10000; i++) { 143 blocks[i].pprev = i ? &blocks[i - 1] : nullptr; 144 blocks[i].nHeight = i; 145 blocks[i].nTime = 1269211443 + i * chainParams->GetConsensus().nPowTargetSpacing; 146 blocks[i].nBits = 0x207fffff; /* target 0x7fffff000... */ 147 blocks[i].nChainWork = i ? blocks[i - 1].nChainWork + GetBlockProof(blocks[i - 1]) : arith_uint256(0); 148 } 149 150 for (int j = 0; j < 1000; j++) { 151 CBlockIndex *p1 = &blocks[m_rng.randrange(10000)]; 152 CBlockIndex *p2 = &blocks[m_rng.randrange(10000)]; 153 CBlockIndex *p3 = &blocks[m_rng.randrange(10000)]; 154 155 int64_t tdiff = GetBlockProofEquivalentTime(*p1, *p2, *p3, chainParams->GetConsensus()); 156 BOOST_CHECK_EQUAL(tdiff, p1->GetBlockTime() - p2->GetBlockTime()); 157 } 158 } 159 160 void sanity_check_chainparams(const ArgsManager& args, ChainType chain_type) 161 { 162 const auto chainParams = CreateChainParams(args, chain_type); 163 const auto consensus = chainParams->GetConsensus(); 164 165 // hash genesis is correct 166 BOOST_CHECK_EQUAL(consensus.hashGenesisBlock, chainParams->GenesisBlock().GetHash()); 167 168 // target timespan is an even multiple of spacing 169 BOOST_CHECK_EQUAL(consensus.nPowTargetTimespan % consensus.nPowTargetSpacing, 0); 170 171 // genesis nBits is positive, doesn't overflow and is lower than powLimit 172 arith_uint256 pow_compact; 173 bool neg, over; 174 pow_compact.SetCompact(chainParams->GenesisBlock().nBits, &neg, &over); 175 BOOST_CHECK(!neg && pow_compact != 0); 176 BOOST_CHECK(!over); 177 BOOST_CHECK(UintToArith256(consensus.powLimit) >= pow_compact); 178 179 // check max target * 4*nPowTargetTimespan doesn't overflow -- see pow.cpp:CalculateNextWorkRequired() 180 if (!consensus.fPowNoRetargeting) { 181 arith_uint256 targ_max{UintToArith256(uint256{"ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"})}; 182 targ_max /= consensus.nPowTargetTimespan*4; 183 BOOST_CHECK(UintToArith256(consensus.powLimit) < targ_max); 184 } 185 } 186 187 BOOST_AUTO_TEST_CASE(ChainParams_MAIN_sanity) 188 { 189 sanity_check_chainparams(*m_node.args, ChainType::MAIN); 190 } 191 192 BOOST_AUTO_TEST_CASE(ChainParams_REGTEST_sanity) 193 { 194 sanity_check_chainparams(*m_node.args, ChainType::REGTEST); 195 } 196 197 BOOST_AUTO_TEST_CASE(ChainParams_TESTNET_sanity) 198 { 199 sanity_check_chainparams(*m_node.args, ChainType::TESTNET); 200 } 201 202 BOOST_AUTO_TEST_CASE(ChainParams_TESTNET4_sanity) 203 { 204 sanity_check_chainparams(*m_node.args, ChainType::TESTNET4); 205 } 206 207 BOOST_AUTO_TEST_CASE(ChainParams_SIGNET_sanity) 208 { 209 sanity_check_chainparams(*m_node.args, ChainType::SIGNET); 210 } 211 212 BOOST_AUTO_TEST_SUITE_END()