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/common.h> 14 #include <test/util/random.h> 15 #include <test/util/script.h> 16 #include <test/util/setup_common.h> 17 #include <util/time.h> 18 #include <validation.h> 19 #include <validationinterface.h> 20 21 #include <thread> 22 23 using kernel::ChainstateRole; 24 using node::BlockAssembler; 25 26 namespace validation_block_tests { 27 struct MinerTestingSetup : public RegTestingSetup { 28 std::shared_ptr<CBlock> Block(const uint256& prev_hash); 29 std::shared_ptr<const CBlock> GoodBlock(const uint256& prev_hash); 30 std::shared_ptr<const CBlock> BadBlock(const uint256& prev_hash); 31 std::shared_ptr<CBlock> FinalizeBlock(std::shared_ptr<CBlock> pblock); 32 void BuildChain(const uint256& root, int height, unsigned int invalid_rate, unsigned int branch_rate, unsigned int max_size, std::vector<std::shared_ptr<const CBlock>>& blocks); 33 }; 34 } // namespace validation_block_tests 35 36 BOOST_FIXTURE_TEST_SUITE(validation_block_tests, MinerTestingSetup) 37 38 struct TestSubscriber final : public CValidationInterface { 39 uint256 m_expected_tip; 40 41 explicit TestSubscriber(uint256 tip) : m_expected_tip(tip) {} 42 43 void UpdatedBlockTip(const CBlockIndex* pindexNew, const CBlockIndex* pindexFork, bool fInitialDownload) override 44 { 45 BOOST_CHECK_EQUAL(m_expected_tip, pindexNew->GetBlockHash()); 46 } 47 48 void BlockConnected(const ChainstateRole& role, const std::shared_ptr<const CBlock>& block, const CBlockIndex* pindex) override 49 { 50 BOOST_CHECK_EQUAL(m_expected_tip, block->hashPrevBlock); 51 BOOST_CHECK_EQUAL(m_expected_tip, pindex->pprev->GetBlockHash()); 52 53 m_expected_tip = block->GetHash(); 54 } 55 56 void BlockDisconnected(const std::shared_ptr<const CBlock>& block, const CBlockIndex* pindex) override 57 { 58 BOOST_CHECK_EQUAL(m_expected_tip, block->GetHash()); 59 BOOST_CHECK_EQUAL(m_expected_tip, pindex->GetBlockHash()); 60 61 m_expected_tip = block->hashPrevBlock; 62 } 63 }; 64 65 std::shared_ptr<CBlock> MinerTestingSetup::Block(const uint256& prev_hash) 66 { 67 static int i = 0; 68 static uint64_t time = Params().GenesisBlock().nTime; 69 70 BlockAssembler::Options options; 71 options.coinbase_output_script = CScript{} << i++ << OP_TRUE; 72 options.include_dummy_extranonce = true; 73 auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock(); 74 auto pblock = std::make_shared<CBlock>(ptemplate->block); 75 pblock->hashPrevBlock = prev_hash; 76 pblock->nTime = ++time; 77 78 // Make the coinbase transaction with two outputs: 79 // One zero-value one that has a unique pubkey to make sure that blocks at the same height can have a different hash 80 // Another one that has the coinbase reward in a P2WSH with OP_TRUE as witness program to make it easy to spend 81 CMutableTransaction txCoinbase(*pblock->vtx[0]); 82 txCoinbase.vout.resize(2); 83 txCoinbase.vout[1].scriptPubKey = P2WSH_OP_TRUE; 84 txCoinbase.vout[1].nValue = txCoinbase.vout[0].nValue; 85 txCoinbase.vout[0].nValue = 0; 86 txCoinbase.vin[0].scriptWitness.SetNull(); 87 // Always pad with OP_0 as dummy extraNonce (also avoids bad-cb-length error for block <=16) 88 const int prev_height{WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(prev_hash)->nHeight)}; 89 txCoinbase.vin[0].scriptSig = CScript{} << prev_height + 1 << OP_0; 90 txCoinbase.nLockTime = static_cast<uint32_t>(prev_height); 91 pblock->vtx[0] = MakeTransactionRef(std::move(txCoinbase)); 92 93 return pblock; 94 } 95 96 std::shared_ptr<CBlock> MinerTestingSetup::FinalizeBlock(std::shared_ptr<CBlock> pblock) 97 { 98 const CBlockIndex* prev_block{WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(pblock->hashPrevBlock))}; 99 m_node.chainman->GenerateCoinbaseCommitment(*pblock, prev_block); 100 101 pblock->hashMerkleRoot = BlockMerkleRoot(*pblock); 102 103 while (!CheckProofOfWork(pblock->GetHash(), pblock->nBits, Params().GetConsensus())) { 104 ++(pblock->nNonce); 105 } 106 107 // submit block header, so that miner can get the block height from the 108 // global state and the node has the topology of the chain 109 BlockValidationState ignored; 110 BOOST_CHECK(Assert(m_node.chainman)->ProcessNewBlockHeaders({{*pblock}}, true, ignored)); 111 112 return pblock; 113 } 114 115 // construct a valid block 116 std::shared_ptr<const CBlock> MinerTestingSetup::GoodBlock(const uint256& prev_hash) 117 { 118 return FinalizeBlock(Block(prev_hash)); 119 } 120 121 // construct an invalid block (but with a valid header) 122 std::shared_ptr<const CBlock> MinerTestingSetup::BadBlock(const uint256& prev_hash) 123 { 124 auto pblock = Block(prev_hash); 125 126 CMutableTransaction coinbase_spend; 127 coinbase_spend.vin.emplace_back(COutPoint(pblock->vtx[0]->GetHash(), 0), CScript(), 0); 128 coinbase_spend.vout.push_back(pblock->vtx[0]->vout[0]); 129 130 CTransactionRef tx = MakeTransactionRef(coinbase_spend); 131 pblock->vtx.push_back(tx); 132 133 auto ret = FinalizeBlock(pblock); 134 return ret; 135 } 136 137 // NOLINTNEXTLINE(misc-no-recursion) 138 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) 139 { 140 if (height <= 0 || blocks.size() >= max_size) return; 141 142 bool gen_invalid = m_rng.randrange(100U) < invalid_rate; 143 bool gen_fork = m_rng.randrange(100U) < branch_rate; 144 145 const std::shared_ptr<const CBlock> pblock = gen_invalid ? BadBlock(root) : GoodBlock(root); 146 blocks.push_back(pblock); 147 if (!gen_invalid) { 148 BuildChain(pblock->GetHash(), height - 1, invalid_rate, branch_rate, max_size, blocks); 149 } 150 151 if (gen_fork) { 152 blocks.push_back(GoodBlock(root)); 153 BuildChain(blocks.back()->GetHash(), height - 1, invalid_rate, branch_rate, max_size, blocks); 154 } 155 } 156 157 BOOST_AUTO_TEST_CASE(processnewblock_signals_ordering) 158 { 159 // build a large-ish chain that's likely to have some forks 160 std::vector<std::shared_ptr<const CBlock>> blocks; 161 while (blocks.size() < 50) { 162 blocks.clear(); 163 BuildChain(Params().GenesisBlock().GetHash(), 100, 15, 10, 500, blocks); 164 } 165 166 bool ignored; 167 // Connect the genesis block and drain any outstanding events 168 BOOST_CHECK(Assert(m_node.chainman)->ProcessNewBlock(std::make_shared<CBlock>(Params().GenesisBlock()), true, true, &ignored)); 169 m_node.validation_signals->SyncWithValidationInterfaceQueue(); 170 171 // subscribe to events (this subscriber will validate event ordering) 172 const CBlockIndex* initial_tip = nullptr; 173 { 174 LOCK(cs_main); 175 initial_tip = m_node.chainman->ActiveChain().Tip(); 176 } 177 auto sub = std::make_shared<TestSubscriber>(initial_tip->GetBlockHash()); 178 m_node.validation_signals->RegisterSharedValidationInterface(sub); 179 180 // create a bunch of threads that repeatedly process a block generated above at random 181 // this will create parallelism and randomness inside validation - the ValidationInterface 182 // will subscribe to events generated during block validation and assert on ordering invariance 183 std::vector<std::thread> threads; 184 threads.reserve(10); 185 for (int i = 0; i < 10; i++) { 186 threads.emplace_back([&]() { 187 bool ignored; 188 FastRandomContext insecure; 189 for (int i = 0; i < 1000; i++) { 190 const auto& block = blocks[insecure.randrange(blocks.size() - 1)]; 191 Assert(m_node.chainman)->ProcessNewBlock(block, true, true, &ignored); 192 } 193 194 // to make sure that eventually we process the full chain - do it here 195 for (const auto& block : blocks) { 196 if (block->vtx.size() == 1) { 197 bool processed = Assert(m_node.chainman)->ProcessNewBlock(block, true, true, &ignored); 198 assert(processed); 199 } 200 } 201 }); 202 } 203 204 for (auto& t : threads) { 205 t.join(); 206 } 207 m_node.validation_signals->SyncWithValidationInterfaceQueue(); 208 209 m_node.validation_signals->UnregisterSharedValidationInterface(sub); 210 211 LOCK(cs_main); 212 BOOST_CHECK_EQUAL(sub->m_expected_tip, m_node.chainman->ActiveChain().Tip()->GetBlockHash()); 213 } 214 215 /** 216 * Test that mempool updates happen atomically with reorgs. 217 * 218 * This prevents RPC clients, among others, from retrieving immediately-out-of-date mempool data 219 * during large reorgs. 220 * 221 * The test verifies this by creating a chain of `num_txs` blocks, matures their coinbases, and then 222 * submits txns spending from their coinbase to the mempool. A fork chain is then processed, 223 * invalidating the txns and evicting them from the mempool. 224 * 225 * We verify that the mempool updates atomically by polling it continuously 226 * from another thread during the reorg and checking that its size only changes 227 * once. The size changing exactly once indicates that the polling thread's 228 * view of the mempool is either consistent with the chain state before reorg, 229 * or consistent with the chain state after the reorg, and not just consistent 230 * with some intermediate state during the reorg. 231 */ 232 BOOST_AUTO_TEST_CASE(mempool_locks_reorg) 233 { 234 bool ignored; 235 auto ProcessBlock = [&](std::shared_ptr<const CBlock> block) -> bool { 236 return Assert(m_node.chainman)->ProcessNewBlock(block, /*force_processing=*/true, /*min_pow_checked=*/true, /*new_block=*/&ignored); 237 }; 238 239 // Process all mined blocks 240 BOOST_REQUIRE(ProcessBlock(std::make_shared<CBlock>(Params().GenesisBlock()))); 241 auto last_mined = GoodBlock(Params().GenesisBlock().GetHash()); 242 BOOST_REQUIRE(ProcessBlock(last_mined)); 243 244 // Run the test multiple times 245 for (int test_runs = 3; test_runs > 0; --test_runs) { 246 BOOST_CHECK_EQUAL(last_mined->GetHash(), WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return m_node.chainman->ActiveChain().Tip()->GetBlockHash())); 247 248 // Later on split from here 249 const uint256 split_hash{last_mined->hashPrevBlock}; 250 251 // Create a bunch of transactions to spend the miner rewards of the 252 // most recent blocks 253 std::vector<CTransactionRef> txs; 254 for (int num_txs = 22; num_txs > 0; --num_txs) { 255 CMutableTransaction mtx; 256 mtx.vin.emplace_back(COutPoint{last_mined->vtx[0]->GetHash(), 1}, CScript{}); 257 mtx.vin[0].scriptWitness.stack.push_back(WITNESS_STACK_ELEM_OP_TRUE); 258 mtx.vout.push_back(last_mined->vtx[0]->vout[1]); 259 mtx.vout[0].nValue -= 1000; 260 txs.push_back(MakeTransactionRef(mtx)); 261 262 last_mined = GoodBlock(last_mined->GetHash()); 263 BOOST_REQUIRE(ProcessBlock(last_mined)); 264 } 265 266 // Mature the inputs of the txs 267 for (int j = COINBASE_MATURITY; j > 0; --j) { 268 last_mined = GoodBlock(last_mined->GetHash()); 269 BOOST_REQUIRE(ProcessBlock(last_mined)); 270 } 271 272 // Mine a reorg (and hold it back) before adding the txs to the mempool 273 const uint256 tip_init{last_mined->GetHash()}; 274 275 std::vector<std::shared_ptr<const CBlock>> reorg; 276 last_mined = GoodBlock(split_hash); 277 reorg.push_back(last_mined); 278 for (size_t j = COINBASE_MATURITY + txs.size() + 1; j > 0; --j) { 279 last_mined = GoodBlock(last_mined->GetHash()); 280 reorg.push_back(last_mined); 281 } 282 283 // Add the txs to the tx pool 284 { 285 LOCK(cs_main); 286 for (const auto& tx : txs) { 287 const MempoolAcceptResult result = m_node.chainman->ProcessTransaction(tx); 288 BOOST_REQUIRE(result.m_result_type == MempoolAcceptResult::ResultType::VALID); 289 } 290 } 291 292 // Check that all txs are in the pool 293 { 294 BOOST_CHECK_EQUAL(m_node.mempool->size(), txs.size()); 295 } 296 297 // Run a thread that simulates an RPC caller that is polling while 298 // validation is doing a reorg 299 std::thread rpc_thread{[&]() { 300 // This thread is checking that the mempool either contains all of 301 // the transactions invalidated by the reorg, or none of them, and 302 // not some intermediate amount. 303 while (true) { 304 LOCK(m_node.mempool->cs); 305 if (m_node.mempool->size() == 0) { 306 // We are done with the reorg 307 break; 308 } 309 // Internally, we might be in the middle of the reorg, but 310 // externally the reorg to the most-proof-of-work chain should 311 // be atomic. So the caller assumes that the returned mempool 312 // is consistent. That is, it has all txs that were there 313 // before the reorg. 314 assert(m_node.mempool->size() == txs.size()); 315 continue; 316 } 317 LOCK(cs_main); 318 // We are done with the reorg, so the tip must have changed 319 assert(tip_init != m_node.chainman->ActiveChain().Tip()->GetBlockHash()); 320 }}; 321 322 // Submit the reorg in this thread to invalidate and remove the txs from the tx pool 323 for (const auto& b : reorg) { 324 ProcessBlock(b); 325 } 326 // Check that the reorg was eventually successful 327 BOOST_CHECK_EQUAL(last_mined->GetHash(), WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return m_node.chainman->ActiveChain().Tip()->GetBlockHash())); 328 329 // We can join the other thread, which returns when the reorg was successful 330 rpc_thread.join(); 331 } 332 } 333 334 BOOST_AUTO_TEST_CASE(witness_commitment_index) 335 { 336 LOCK(Assert(m_node.chainman)->GetMutex()); 337 CScript pubKey; 338 pubKey << 1 << OP_TRUE; 339 BlockAssembler::Options options; 340 options.coinbase_output_script = pubKey; 341 options.include_dummy_extranonce = true; 342 auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock(); 343 CBlock pblock = ptemplate->block; 344 345 CTxOut witness; 346 witness.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT); 347 witness.scriptPubKey[0] = OP_RETURN; 348 witness.scriptPubKey[1] = 0x24; 349 witness.scriptPubKey[2] = 0xaa; 350 witness.scriptPubKey[3] = 0x21; 351 witness.scriptPubKey[4] = 0xa9; 352 witness.scriptPubKey[5] = 0xed; 353 354 // A witness larger than the minimum size is still valid 355 CTxOut min_plus_one = witness; 356 min_plus_one.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT + 1); 357 358 CTxOut invalid = witness; 359 invalid.scriptPubKey[0] = OP_VERIFY; 360 361 CMutableTransaction txCoinbase(*pblock.vtx[0]); 362 txCoinbase.vout.resize(4); 363 txCoinbase.vout[0] = witness; 364 txCoinbase.vout[1] = witness; 365 txCoinbase.vout[2] = min_plus_one; 366 txCoinbase.vout[3] = invalid; 367 pblock.vtx[0] = MakeTransactionRef(std::move(txCoinbase)); 368 369 BOOST_CHECK_EQUAL(GetWitnessCommitmentIndex(pblock), 2); 370 } 371 BOOST_AUTO_TEST_SUITE_END()