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