validation_block_tests.cpp
1 // Copyright (c) 2018-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 <boost/test/unit_test.hpp> 6 7 #include <chainparams.h> 8 #include <consensus/merkle.h> 9 #include <consensus/validation.h> 10 #include <node/miner.h> 11 #include <pow.h> 12 #include <random.h> 13 #include <test/util/random.h> 14 #include <test/util/script.h> 15 #include <test/util/setup_common.h> 16 #include <util/time.h> 17 #include <validation.h> 18 #include <validationinterface.h> 19 20 #include <thread> 21 22 using node::BlockAssembler; 23 24 namespace validation_block_tests { 25 struct MinerTestingSetup : public RegTestingSetup { 26 std::shared_ptr<CBlock> Block(const uint256& prev_hash); 27 std::shared_ptr<const CBlock> GoodBlock(const uint256& prev_hash); 28 std::shared_ptr<const CBlock> BadBlock(const uint256& prev_hash); 29 std::shared_ptr<CBlock> FinalizeBlock(std::shared_ptr<CBlock> pblock); 30 void BuildChain(const uint256& root, int height, const unsigned int invalid_rate, const unsigned int branch_rate, const unsigned int max_size, std::vector<std::shared_ptr<const CBlock>>& blocks); 31 }; 32 } // namespace validation_block_tests 33 34 BOOST_FIXTURE_TEST_SUITE(validation_block_tests, MinerTestingSetup) 35 36 struct TestSubscriber final : public CValidationInterface { 37 uint256 m_expected_tip; 38 39 explicit TestSubscriber(uint256 tip) : m_expected_tip(tip) {} 40 41 void UpdatedBlockTip(const CBlockIndex* pindexNew, const CBlockIndex* pindexFork, bool fInitialDownload) override 42 { 43 BOOST_CHECK_EQUAL(m_expected_tip, pindexNew->GetBlockHash()); 44 } 45 46 void BlockConnected(ChainstateRole role, const std::shared_ptr<const CBlock>& block, const CBlockIndex* pindex) override 47 { 48 BOOST_CHECK_EQUAL(m_expected_tip, block->hashPrevBlock); 49 BOOST_CHECK_EQUAL(m_expected_tip, pindex->pprev->GetBlockHash()); 50 51 m_expected_tip = block->GetHash(); 52 } 53 54 void BlockDisconnected(const std::shared_ptr<const CBlock>& block, const CBlockIndex* pindex) override 55 { 56 BOOST_CHECK_EQUAL(m_expected_tip, block->GetHash()); 57 BOOST_CHECK_EQUAL(m_expected_tip, pindex->GetBlockHash()); 58 59 m_expected_tip = block->hashPrevBlock; 60 } 61 }; 62 63 std::shared_ptr<CBlock> MinerTestingSetup::Block(const uint256& prev_hash) 64 { 65 static int i = 0; 66 static uint64_t time = Params().GenesisBlock().nTime; 67 68 BlockAssembler::Options options; 69 options.coinbase_output_script = CScript{} << i++ << OP_TRUE; 70 auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock(); 71 auto pblock = std::make_shared<CBlock>(ptemplate->block); 72 pblock->hashPrevBlock = prev_hash; 73 pblock->nTime = ++time; 74 75 // Make the coinbase transaction with two outputs: 76 // One zero-value one that has a unique pubkey to make sure that blocks at the same height can have a different hash 77 // Another one that has the coinbase reward in a P2WSH with OP_TRUE as witness program to make it easy to spend 78 CMutableTransaction txCoinbase(*pblock->vtx[0]); 79 txCoinbase.vout.resize(2); 80 txCoinbase.vout[1].scriptPubKey = P2WSH_OP_TRUE; 81 txCoinbase.vout[1].nValue = txCoinbase.vout[0].nValue; 82 txCoinbase.vout[0].nValue = 0; 83 txCoinbase.vin[0].scriptWitness.SetNull(); 84 // Always pad with OP_0 at the end to avoid bad-cb-length error 85 const int prev_height{WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(prev_hash)->nHeight)}; 86 txCoinbase.vin[0].scriptSig = CScript{} << prev_height + 1 << OP_0; 87 txCoinbase.nLockTime = static_cast<uint32_t>(prev_height); 88 pblock->vtx[0] = MakeTransactionRef(std::move(txCoinbase)); 89 90 return pblock; 91 } 92 93 std::shared_ptr<CBlock> MinerTestingSetup::FinalizeBlock(std::shared_ptr<CBlock> pblock) 94 { 95 const CBlockIndex* prev_block{WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(pblock->hashPrevBlock))}; 96 m_node.chainman->GenerateCoinbaseCommitment(*pblock, prev_block); 97 98 pblock->hashMerkleRoot = BlockMerkleRoot(*pblock); 99 100 while (!CheckProofOfWork(pblock->GetHash(), pblock->nBits, Params().GetConsensus())) { 101 ++(pblock->nNonce); 102 } 103 104 // submit block header, so that miner can get the block height from the 105 // global state and the node has the topology of the chain 106 BlockValidationState ignored; 107 BOOST_CHECK(Assert(m_node.chainman)->ProcessNewBlockHeaders({{pblock->GetBlockHeader()}}, true, ignored)); 108 109 return pblock; 110 } 111 112 // construct a valid block 113 std::shared_ptr<const CBlock> MinerTestingSetup::GoodBlock(const uint256& prev_hash) 114 { 115 return FinalizeBlock(Block(prev_hash)); 116 } 117 118 // construct an invalid block (but with a valid header) 119 std::shared_ptr<const CBlock> MinerTestingSetup::BadBlock(const uint256& prev_hash) 120 { 121 auto pblock = Block(prev_hash); 122 123 CMutableTransaction coinbase_spend; 124 coinbase_spend.vin.emplace_back(COutPoint(pblock->vtx[0]->GetHash(), 0), CScript(), 0); 125 coinbase_spend.vout.push_back(pblock->vtx[0]->vout[0]); 126 127 CTransactionRef tx = MakeTransactionRef(coinbase_spend); 128 pblock->vtx.push_back(tx); 129 130 auto ret = FinalizeBlock(pblock); 131 return ret; 132 } 133 134 // NOLINTNEXTLINE(misc-no-recursion) 135 void MinerTestingSetup::BuildChain(const uint256& root, int height, const unsigned int invalid_rate, const unsigned int branch_rate, const unsigned int max_size, std::vector<std::shared_ptr<const CBlock>>& blocks) 136 { 137 if (height <= 0 || blocks.size() >= max_size) return; 138 139 bool gen_invalid = m_rng.randrange(100U) < invalid_rate; 140 bool gen_fork = m_rng.randrange(100U) < branch_rate; 141 142 const std::shared_ptr<const CBlock> pblock = gen_invalid ? BadBlock(root) : GoodBlock(root); 143 blocks.push_back(pblock); 144 if (!gen_invalid) { 145 BuildChain(pblock->GetHash(), height - 1, invalid_rate, branch_rate, max_size, blocks); 146 } 147 148 if (gen_fork) { 149 blocks.push_back(GoodBlock(root)); 150 BuildChain(blocks.back()->GetHash(), height - 1, invalid_rate, branch_rate, max_size, blocks); 151 } 152 } 153 154 BOOST_AUTO_TEST_CASE(processnewblock_signals_ordering) 155 { 156 // build a large-ish chain that's likely to have some forks 157 std::vector<std::shared_ptr<const CBlock>> blocks; 158 while (blocks.size() < 50) { 159 blocks.clear(); 160 BuildChain(Params().GenesisBlock().GetHash(), 100, 15, 10, 500, blocks); 161 } 162 163 bool ignored; 164 // Connect the genesis block and drain any outstanding events 165 BOOST_CHECK(Assert(m_node.chainman)->ProcessNewBlock(std::make_shared<CBlock>(Params().GenesisBlock()), true, true, &ignored)); 166 m_node.validation_signals->SyncWithValidationInterfaceQueue(); 167 168 // subscribe to events (this subscriber will validate event ordering) 169 const CBlockIndex* initial_tip = nullptr; 170 { 171 LOCK(cs_main); 172 initial_tip = m_node.chainman->ActiveChain().Tip(); 173 } 174 auto sub = std::make_shared<TestSubscriber>(initial_tip->GetBlockHash()); 175 m_node.validation_signals->RegisterSharedValidationInterface(sub); 176 177 // create a bunch of threads that repeatedly process a block generated above at random 178 // this will create parallelism and randomness inside validation - the ValidationInterface 179 // will subscribe to events generated during block validation and assert on ordering invariance 180 std::vector<std::thread> threads; 181 threads.reserve(10); 182 for (int i = 0; i < 10; i++) { 183 threads.emplace_back([&]() { 184 bool ignored; 185 FastRandomContext insecure; 186 for (int i = 0; i < 1000; i++) { 187 const auto& block = blocks[insecure.randrange(blocks.size() - 1)]; 188 Assert(m_node.chainman)->ProcessNewBlock(block, true, true, &ignored); 189 } 190 191 // to make sure that eventually we process the full chain - do it here 192 for (const auto& block : blocks) { 193 if (block->vtx.size() == 1) { 194 bool processed = Assert(m_node.chainman)->ProcessNewBlock(block, true, true, &ignored); 195 assert(processed); 196 } 197 } 198 }); 199 } 200 201 for (auto& t : threads) { 202 t.join(); 203 } 204 m_node.validation_signals->SyncWithValidationInterfaceQueue(); 205 206 m_node.validation_signals->UnregisterSharedValidationInterface(sub); 207 208 LOCK(cs_main); 209 BOOST_CHECK_EQUAL(sub->m_expected_tip, m_node.chainman->ActiveChain().Tip()->GetBlockHash()); 210 } 211 212 /** 213 * Test that mempool updates happen atomically with reorgs. 214 * 215 * This prevents RPC clients, among others, from retrieving immediately-out-of-date mempool data 216 * during large reorgs. 217 * 218 * The test verifies this by creating a chain of `num_txs` blocks, matures their coinbases, and then 219 * submits txns spending from their coinbase to the mempool. A fork chain is then processed, 220 * invalidating the txns and evicting them from the mempool. 221 * 222 * We verify that the mempool updates atomically by polling it continuously 223 * from another thread during the reorg and checking that its size only changes 224 * once. The size changing exactly once indicates that the polling thread's 225 * view of the mempool is either consistent with the chain state before reorg, 226 * or consistent with the chain state after the reorg, and not just consistent 227 * with some intermediate state during the reorg. 228 */ 229 BOOST_AUTO_TEST_CASE(mempool_locks_reorg) 230 { 231 bool ignored; 232 auto ProcessBlock = [&](std::shared_ptr<const CBlock> block) -> bool { 233 return Assert(m_node.chainman)->ProcessNewBlock(block, /*force_processing=*/true, /*min_pow_checked=*/true, /*new_block=*/&ignored); 234 }; 235 236 // Process all mined blocks 237 BOOST_REQUIRE(ProcessBlock(std::make_shared<CBlock>(Params().GenesisBlock()))); 238 auto last_mined = GoodBlock(Params().GenesisBlock().GetHash()); 239 BOOST_REQUIRE(ProcessBlock(last_mined)); 240 241 // Run the test multiple times 242 for (int test_runs = 3; test_runs > 0; --test_runs) { 243 BOOST_CHECK_EQUAL(last_mined->GetHash(), WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return m_node.chainman->ActiveChain().Tip()->GetBlockHash())); 244 245 // Later on split from here 246 const uint256 split_hash{last_mined->hashPrevBlock}; 247 248 // Create a bunch of transactions to spend the miner rewards of the 249 // most recent blocks 250 std::vector<CTransactionRef> txs; 251 for (int num_txs = 22; num_txs > 0; --num_txs) { 252 CMutableTransaction mtx; 253 mtx.vin.emplace_back(COutPoint{last_mined->vtx[0]->GetHash(), 1}, CScript{}); 254 mtx.vin[0].scriptWitness.stack.push_back(WITNESS_STACK_ELEM_OP_TRUE); 255 mtx.vout.push_back(last_mined->vtx[0]->vout[1]); 256 mtx.vout[0].nValue -= 1000; 257 txs.push_back(MakeTransactionRef(mtx)); 258 259 last_mined = GoodBlock(last_mined->GetHash()); 260 BOOST_REQUIRE(ProcessBlock(last_mined)); 261 } 262 263 // Mature the inputs of the txs 264 for (int j = COINBASE_MATURITY; j > 0; --j) { 265 last_mined = GoodBlock(last_mined->GetHash()); 266 BOOST_REQUIRE(ProcessBlock(last_mined)); 267 } 268 269 // Mine a reorg (and hold it back) before adding the txs to the mempool 270 const uint256 tip_init{last_mined->GetHash()}; 271 272 std::vector<std::shared_ptr<const CBlock>> reorg; 273 last_mined = GoodBlock(split_hash); 274 reorg.push_back(last_mined); 275 for (size_t j = COINBASE_MATURITY + txs.size() + 1; j > 0; --j) { 276 last_mined = GoodBlock(last_mined->GetHash()); 277 reorg.push_back(last_mined); 278 } 279 280 // Add the txs to the tx pool 281 { 282 LOCK(cs_main); 283 for (const auto& tx : txs) { 284 const MempoolAcceptResult result = m_node.chainman->ProcessTransaction(tx); 285 BOOST_REQUIRE(result.m_result_type == MempoolAcceptResult::ResultType::VALID); 286 } 287 } 288 289 // Check that all txs are in the pool 290 { 291 BOOST_CHECK_EQUAL(m_node.mempool->size(), txs.size()); 292 } 293 294 // Run a thread that simulates an RPC caller that is polling while 295 // validation is doing a reorg 296 std::thread rpc_thread{[&]() { 297 // This thread is checking that the mempool either contains all of 298 // the transactions invalidated by the reorg, or none of them, and 299 // not some intermediate amount. 300 while (true) { 301 LOCK(m_node.mempool->cs); 302 if (m_node.mempool->size() == 0) { 303 // We are done with the reorg 304 break; 305 } 306 // Internally, we might be in the middle of the reorg, but 307 // externally the reorg to the most-proof-of-work chain should 308 // be atomic. So the caller assumes that the returned mempool 309 // is consistent. That is, it has all txs that were there 310 // before the reorg. 311 assert(m_node.mempool->size() == txs.size()); 312 continue; 313 } 314 LOCK(cs_main); 315 // We are done with the reorg, so the tip must have changed 316 assert(tip_init != m_node.chainman->ActiveChain().Tip()->GetBlockHash()); 317 }}; 318 319 // Submit the reorg in this thread to invalidate and remove the txs from the tx pool 320 for (const auto& b : reorg) { 321 ProcessBlock(b); 322 } 323 // Check that the reorg was eventually successful 324 BOOST_CHECK_EQUAL(last_mined->GetHash(), WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return m_node.chainman->ActiveChain().Tip()->GetBlockHash())); 325 326 // We can join the other thread, which returns when the reorg was successful 327 rpc_thread.join(); 328 } 329 } 330 331 BOOST_AUTO_TEST_CASE(witness_commitment_index) 332 { 333 LOCK(Assert(m_node.chainman)->GetMutex()); 334 CScript pubKey; 335 pubKey << 1 << OP_TRUE; 336 BlockAssembler::Options options; 337 options.coinbase_output_script = pubKey; 338 auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock(); 339 CBlock pblock = ptemplate->block; 340 341 CTxOut witness; 342 witness.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT); 343 witness.scriptPubKey[0] = OP_RETURN; 344 witness.scriptPubKey[1] = 0x24; 345 witness.scriptPubKey[2] = 0xaa; 346 witness.scriptPubKey[3] = 0x21; 347 witness.scriptPubKey[4] = 0xa9; 348 witness.scriptPubKey[5] = 0xed; 349 350 // A witness larger than the minimum size is still valid 351 CTxOut min_plus_one = witness; 352 min_plus_one.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT + 1); 353 354 CTxOut invalid = witness; 355 invalid.scriptPubKey[0] = OP_VERIFY; 356 357 CMutableTransaction txCoinbase(*pblock.vtx[0]); 358 txCoinbase.vout.resize(4); 359 txCoinbase.vout[0] = witness; 360 txCoinbase.vout[1] = witness; 361 txCoinbase.vout[2] = min_plus_one; 362 txCoinbase.vout[3] = invalid; 363 pblock.vtx[0] = MakeTransactionRef(std::move(txCoinbase)); 364 365 BOOST_CHECK_EQUAL(GetWitnessCommitmentIndex(pblock), 2); 366 } 367 BOOST_AUTO_TEST_SUITE_END()