validation_block_tests.cpp
1 // Copyright (c) 2018-2022 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 auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get()}.CreateNewBlock(CScript{} << i++ << OP_TRUE); 69 auto pblock = std::make_shared<CBlock>(ptemplate->block); 70 pblock->hashPrevBlock = prev_hash; 71 pblock->nTime = ++time; 72 73 // Make the coinbase transaction with two outputs: 74 // One zero-value one that has a unique pubkey to make sure that blocks at the same height can have a different hash 75 // Another one that has the coinbase reward in a P2WSH with OP_TRUE as witness program to make it easy to spend 76 CMutableTransaction txCoinbase(*pblock->vtx[0]); 77 txCoinbase.vout.resize(2); 78 txCoinbase.vout[1].scriptPubKey = P2WSH_OP_TRUE; 79 txCoinbase.vout[1].nValue = txCoinbase.vout[0].nValue; 80 txCoinbase.vout[0].nValue = 0; 81 txCoinbase.vin[0].scriptWitness.SetNull(); 82 // Always pad with OP_0 at the end to avoid bad-cb-length error 83 txCoinbase.vin[0].scriptSig = CScript{} << WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(prev_hash)->nHeight + 1) << OP_0; 84 pblock->vtx[0] = MakeTransactionRef(std::move(txCoinbase)); 85 86 return pblock; 87 } 88 89 std::shared_ptr<CBlock> MinerTestingSetup::FinalizeBlock(std::shared_ptr<CBlock> pblock) 90 { 91 const CBlockIndex* prev_block{WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(pblock->hashPrevBlock))}; 92 m_node.chainman->GenerateCoinbaseCommitment(*pblock, prev_block); 93 94 pblock->hashMerkleRoot = BlockMerkleRoot(*pblock); 95 96 while (!CheckProofOfWork(pblock->GetHash(), pblock->nBits, Params().GetConsensus())) { 97 ++(pblock->nNonce); 98 } 99 100 // submit block header, so that miner can get the block height from the 101 // global state and the node has the topology of the chain 102 BlockValidationState ignored; 103 BOOST_CHECK(Assert(m_node.chainman)->ProcessNewBlockHeaders({pblock->GetBlockHeader()}, true, ignored)); 104 105 return pblock; 106 } 107 108 // construct a valid block 109 std::shared_ptr<const CBlock> MinerTestingSetup::GoodBlock(const uint256& prev_hash) 110 { 111 return FinalizeBlock(Block(prev_hash)); 112 } 113 114 // construct an invalid block (but with a valid header) 115 std::shared_ptr<const CBlock> MinerTestingSetup::BadBlock(const uint256& prev_hash) 116 { 117 auto pblock = Block(prev_hash); 118 119 CMutableTransaction coinbase_spend; 120 coinbase_spend.vin.emplace_back(COutPoint(pblock->vtx[0]->GetHash(), 0), CScript(), 0); 121 coinbase_spend.vout.push_back(pblock->vtx[0]->vout[0]); 122 123 CTransactionRef tx = MakeTransactionRef(coinbase_spend); 124 pblock->vtx.push_back(tx); 125 126 auto ret = FinalizeBlock(pblock); 127 return ret; 128 } 129 130 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) 131 { 132 if (height <= 0 || blocks.size() >= max_size) return; 133 134 bool gen_invalid = InsecureRandRange(100) < invalid_rate; 135 bool gen_fork = InsecureRandRange(100) < branch_rate; 136 137 const std::shared_ptr<const CBlock> pblock = gen_invalid ? BadBlock(root) : GoodBlock(root); 138 blocks.push_back(pblock); 139 if (!gen_invalid) { 140 BuildChain(pblock->GetHash(), height - 1, invalid_rate, branch_rate, max_size, blocks); 141 } 142 143 if (gen_fork) { 144 blocks.push_back(GoodBlock(root)); 145 BuildChain(blocks.back()->GetHash(), height - 1, invalid_rate, branch_rate, max_size, blocks); 146 } 147 } 148 149 BOOST_AUTO_TEST_CASE(processnewblock_signals_ordering) 150 { 151 // build a large-ish chain that's likely to have some forks 152 std::vector<std::shared_ptr<const CBlock>> blocks; 153 while (blocks.size() < 50) { 154 blocks.clear(); 155 BuildChain(Params().GenesisBlock().GetHash(), 100, 15, 10, 500, blocks); 156 } 157 158 bool ignored; 159 // Connect the genesis block and drain any outstanding events 160 BOOST_CHECK(Assert(m_node.chainman)->ProcessNewBlock(std::make_shared<CBlock>(Params().GenesisBlock()), true, true, &ignored)); 161 m_node.validation_signals->SyncWithValidationInterfaceQueue(); 162 163 // subscribe to events (this subscriber will validate event ordering) 164 const CBlockIndex* initial_tip = nullptr; 165 { 166 LOCK(cs_main); 167 initial_tip = m_node.chainman->ActiveChain().Tip(); 168 } 169 auto sub = std::make_shared<TestSubscriber>(initial_tip->GetBlockHash()); 170 m_node.validation_signals->RegisterSharedValidationInterface(sub); 171 172 // create a bunch of threads that repeatedly process a block generated above at random 173 // this will create parallelism and randomness inside validation - the ValidationInterface 174 // will subscribe to events generated during block validation and assert on ordering invariance 175 std::vector<std::thread> threads; 176 threads.reserve(10); 177 for (int i = 0; i < 10; i++) { 178 threads.emplace_back([&]() { 179 bool ignored; 180 FastRandomContext insecure; 181 for (int i = 0; i < 1000; i++) { 182 auto block = blocks[insecure.randrange(blocks.size() - 1)]; 183 Assert(m_node.chainman)->ProcessNewBlock(block, true, true, &ignored); 184 } 185 186 // to make sure that eventually we process the full chain - do it here 187 for (const auto& block : blocks) { 188 if (block->vtx.size() == 1) { 189 bool processed = Assert(m_node.chainman)->ProcessNewBlock(block, true, true, &ignored); 190 assert(processed); 191 } 192 } 193 }); 194 } 195 196 for (auto& t : threads) { 197 t.join(); 198 } 199 m_node.validation_signals->SyncWithValidationInterfaceQueue(); 200 201 m_node.validation_signals->UnregisterSharedValidationInterface(sub); 202 203 LOCK(cs_main); 204 BOOST_CHECK_EQUAL(sub->m_expected_tip, m_node.chainman->ActiveChain().Tip()->GetBlockHash()); 205 } 206 207 /** 208 * Test that mempool updates happen atomically with reorgs. 209 * 210 * This prevents RPC clients, among others, from retrieving immediately-out-of-date mempool data 211 * during large reorgs. 212 * 213 * The test verifies this by creating a chain of `num_txs` blocks, matures their coinbases, and then 214 * submits txns spending from their coinbase to the mempool. A fork chain is then processed, 215 * invalidating the txns and evicting them from the mempool. 216 * 217 * We verify that the mempool updates atomically by polling it continuously 218 * from another thread during the reorg and checking that its size only changes 219 * once. The size changing exactly once indicates that the polling thread's 220 * view of the mempool is either consistent with the chain state before reorg, 221 * or consistent with the chain state after the reorg, and not just consistent 222 * with some intermediate state during the reorg. 223 */ 224 BOOST_AUTO_TEST_CASE(mempool_locks_reorg) 225 { 226 bool ignored; 227 auto ProcessBlock = [&](std::shared_ptr<const CBlock> block) -> bool { 228 return Assert(m_node.chainman)->ProcessNewBlock(block, /*force_processing=*/true, /*min_pow_checked=*/true, /*new_block=*/&ignored); 229 }; 230 231 // Process all mined blocks 232 BOOST_REQUIRE(ProcessBlock(std::make_shared<CBlock>(Params().GenesisBlock()))); 233 auto last_mined = GoodBlock(Params().GenesisBlock().GetHash()); 234 BOOST_REQUIRE(ProcessBlock(last_mined)); 235 236 // Run the test multiple times 237 for (int test_runs = 3; test_runs > 0; --test_runs) { 238 BOOST_CHECK_EQUAL(last_mined->GetHash(), WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return m_node.chainman->ActiveChain().Tip()->GetBlockHash())); 239 240 // Later on split from here 241 const uint256 split_hash{last_mined->hashPrevBlock}; 242 243 // Create a bunch of transactions to spend the miner rewards of the 244 // most recent blocks 245 std::vector<CTransactionRef> txs; 246 for (int num_txs = 22; num_txs > 0; --num_txs) { 247 CMutableTransaction mtx; 248 mtx.vin.emplace_back(COutPoint{last_mined->vtx[0]->GetHash(), 1}, CScript{}); 249 mtx.vin[0].scriptWitness.stack.push_back(WITNESS_STACK_ELEM_OP_TRUE); 250 mtx.vout.push_back(last_mined->vtx[0]->vout[1]); 251 mtx.vout[0].nValue -= 1000; 252 txs.push_back(MakeTransactionRef(mtx)); 253 254 last_mined = GoodBlock(last_mined->GetHash()); 255 BOOST_REQUIRE(ProcessBlock(last_mined)); 256 } 257 258 // Mature the inputs of the txs 259 for (int j = COINBASE_MATURITY; j > 0; --j) { 260 last_mined = GoodBlock(last_mined->GetHash()); 261 BOOST_REQUIRE(ProcessBlock(last_mined)); 262 } 263 264 // Mine a reorg (and hold it back) before adding the txs to the mempool 265 const uint256 tip_init{last_mined->GetHash()}; 266 267 std::vector<std::shared_ptr<const CBlock>> reorg; 268 last_mined = GoodBlock(split_hash); 269 reorg.push_back(last_mined); 270 for (size_t j = COINBASE_MATURITY + txs.size() + 1; j > 0; --j) { 271 last_mined = GoodBlock(last_mined->GetHash()); 272 reorg.push_back(last_mined); 273 } 274 275 // Add the txs to the tx pool 276 { 277 LOCK(cs_main); 278 for (const auto& tx : txs) { 279 const MempoolAcceptResult result = m_node.chainman->ProcessTransaction(tx); 280 BOOST_REQUIRE(result.m_result_type == MempoolAcceptResult::ResultType::VALID); 281 } 282 } 283 284 // Check that all txs are in the pool 285 { 286 BOOST_CHECK_EQUAL(m_node.mempool->size(), txs.size()); 287 } 288 289 // Run a thread that simulates an RPC caller that is polling while 290 // validation is doing a reorg 291 std::thread rpc_thread{[&]() { 292 // This thread is checking that the mempool either contains all of 293 // the transactions invalidated by the reorg, or none of them, and 294 // not some intermediate amount. 295 while (true) { 296 LOCK(m_node.mempool->cs); 297 if (m_node.mempool->size() == 0) { 298 // We are done with the reorg 299 break; 300 } 301 // Internally, we might be in the middle of the reorg, but 302 // externally the reorg to the most-proof-of-work chain should 303 // be atomic. So the caller assumes that the returned mempool 304 // is consistent. That is, it has all txs that were there 305 // before the reorg. 306 assert(m_node.mempool->size() == txs.size()); 307 continue; 308 } 309 LOCK(cs_main); 310 // We are done with the reorg, so the tip must have changed 311 assert(tip_init != m_node.chainman->ActiveChain().Tip()->GetBlockHash()); 312 }}; 313 314 // Submit the reorg in this thread to invalidate and remove the txs from the tx pool 315 for (const auto& b : reorg) { 316 ProcessBlock(b); 317 } 318 // Check that the reorg was eventually successful 319 BOOST_CHECK_EQUAL(last_mined->GetHash(), WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return m_node.chainman->ActiveChain().Tip()->GetBlockHash())); 320 321 // We can join the other thread, which returns when the reorg was successful 322 rpc_thread.join(); 323 } 324 } 325 326 BOOST_AUTO_TEST_CASE(witness_commitment_index) 327 { 328 LOCK(Assert(m_node.chainman)->GetMutex()); 329 CScript pubKey; 330 pubKey << 1 << OP_TRUE; 331 auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get()}.CreateNewBlock(pubKey); 332 CBlock pblock = ptemplate->block; 333 334 CTxOut witness; 335 witness.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT); 336 witness.scriptPubKey[0] = OP_RETURN; 337 witness.scriptPubKey[1] = 0x24; 338 witness.scriptPubKey[2] = 0xaa; 339 witness.scriptPubKey[3] = 0x21; 340 witness.scriptPubKey[4] = 0xa9; 341 witness.scriptPubKey[5] = 0xed; 342 343 // A witness larger than the minimum size is still valid 344 CTxOut min_plus_one = witness; 345 min_plus_one.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT + 1); 346 347 CTxOut invalid = witness; 348 invalid.scriptPubKey[0] = OP_VERIFY; 349 350 CMutableTransaction txCoinbase(*pblock.vtx[0]); 351 txCoinbase.vout.resize(4); 352 txCoinbase.vout[0] = witness; 353 txCoinbase.vout[1] = witness; 354 txCoinbase.vout[2] = min_plus_one; 355 txCoinbase.vout[3] = invalid; 356 pblock.vtx[0] = MakeTransactionRef(std::move(txCoinbase)); 357 358 BOOST_CHECK_EQUAL(GetWitnessCommitmentIndex(pblock), 2); 359 } 360 BOOST_AUTO_TEST_SUITE_END()