validation_block_tests.cpp raw

   1  // Copyright (c) 2018-present The Limenka 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, m_node}.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, m_node}.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()
 366