rbf.cpp raw

   1  // Copyright (c) 2020-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 <node/mempool_args.h>
   6  #include <policy/rbf.h>
   7  #include <primitives/transaction.h>
   8  #include <sync.h>
   9  #include <test/fuzz/FuzzedDataProvider.h>
  10  #include <test/fuzz/fuzz.h>
  11  #include <test/fuzz/util.h>
  12  #include <test/fuzz/util/mempool.h>
  13  #include <test/util/setup_common.h>
  14  #include <test/util/time.h>
  15  #include <test/util/txmempool.h>
  16  #include <txmempool.h>
  17  #include <util/check.h>
  18  #include <util/translation.h>
  19  
  20  #include <cstdint>
  21  #include <optional>
  22  #include <string>
  23  #include <vector>
  24  
  25  namespace {
  26  const BasicTestingSetup* g_setup;
  27  } // namespace
  28  
  29  const int NUM_ITERS = 10000;
  30  
  31  std::vector<COutPoint> g_outpoints;
  32  
  33  void initialize_rbf()
  34  {
  35      static const auto testing_setup = MakeNoLogFileContext<>();
  36      g_setup = testing_setup.get();
  37  }
  38  
  39  void initialize_package_rbf()
  40  {
  41      static const auto testing_setup = MakeNoLogFileContext<>();
  42      g_setup = testing_setup.get();
  43  
  44      // Create a fixed set of unique "UTXOs" to source parents from
  45      // to avoid fuzzer giving circular references
  46      for (int i = 0; i < NUM_ITERS; ++i) {
  47          g_outpoints.emplace_back();
  48          g_outpoints.back().n = i;
  49      }
  50  
  51  }
  52  
  53  FUZZ_TARGET(rbf, .init = initialize_rbf)
  54  {
  55      SeedRandomStateForTest(SeedRand::ZEROS);
  56      FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
  57      FakeNodeClock clock{ConsumeTime(fuzzed_data_provider)};
  58      std::optional<CMutableTransaction> mtx = ConsumeDeserializable<CMutableTransaction>(fuzzed_data_provider, TX_WITH_WITNESS);
  59      if (!mtx) {
  60          return;
  61      }
  62  
  63      bilingual_str error;
  64      CTxMemPool pool{MemPoolOptionsForTest(g_setup->m_node), error};
  65      Assert(error.empty());
  66  
  67      LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), NUM_ITERS)
  68      {
  69          const std::optional<CMutableTransaction> another_mtx = ConsumeDeserializable<CMutableTransaction>(fuzzed_data_provider, TX_WITH_WITNESS);
  70          if (!another_mtx) {
  71              break;
  72          }
  73          const CTransaction another_tx{*another_mtx};
  74          if (fuzzed_data_provider.ConsumeBool() && !mtx->vin.empty()) {
  75              mtx->vin[0].prevout = COutPoint{another_tx.GetHash(), 0};
  76          }
  77          LOCK2(cs_main, pool.cs);
  78          if (!pool.GetIter(another_tx.GetHash())) {
  79              TryAddToMempool(pool, ConsumeTxMemPoolEntry(fuzzed_data_provider, another_tx));
  80          }
  81      }
  82      const CTransaction tx{*mtx};
  83      if (fuzzed_data_provider.ConsumeBool()) {
  84          LOCK2(cs_main, pool.cs);
  85          if (!pool.GetIter(tx.GetHash())) {
  86              TryAddToMempool(pool, ConsumeTxMemPoolEntry(fuzzed_data_provider, tx));
  87          }
  88      }
  89      {
  90          LOCK(pool.cs);
  91          (void)IsRBFOptIn(tx, pool);
  92      }
  93  }
  94  
  95  FUZZ_TARGET(package_rbf, .init = initialize_package_rbf)
  96  {
  97      SeedRandomStateForTest(SeedRand::ZEROS);
  98      FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
  99      FakeNodeClock clock{ConsumeTime(fuzzed_data_provider)};
 100  
 101      // "Real" virtual size is not important for this test since ConsumeTxMemPoolEntry generates its own virtual size values
 102      // so we construct small transactions for performance reasons. Child simply needs an input for later to perhaps connect to parent.
 103      CMutableTransaction child;
 104      child.vin.resize(1);
 105  
 106      bilingual_str error;
 107      CTxMemPool pool{MemPoolOptionsForTest(g_setup->m_node), error};
 108      Assert(error.empty());
 109  
 110      // Add a bunch of parent-child pairs to the mempool, and remember them.
 111      std::vector<CTransaction> mempool_txs;
 112      uint32_t iter{0};
 113  
 114      // Keep track of the total vsize of CTxMemPoolEntry's being added to the mempool to avoid overflow
 115      // Add replacement_vsize since this is added to new diagram during RBF check
 116      std::optional<CMutableTransaction> replacement_tx = ConsumeDeserializable<CMutableTransaction>(fuzzed_data_provider, TX_WITH_WITNESS);
 117      if (!replacement_tx) {
 118          return;
 119      }
 120      replacement_tx->vin.resize(1);
 121      replacement_tx->vin[0].prevout = g_outpoints.at(iter++);
 122      CTransaction replacement_tx_final{*replacement_tx};
 123      auto replacement_entry = ConsumeTxMemPoolEntry(fuzzed_data_provider, replacement_tx_final);
 124      int32_t replacement_weight = replacement_entry.GetAdjustedWeight();
 125      // Ensure that we don't hit FeeFrac limits, as we store TxGraph entries in terms of FeePerWeight
 126      int64_t running_vsize_total{replacement_entry.GetTxSize()};
 127  
 128      LOCK2(cs_main, pool.cs);
 129  
 130      while (fuzzed_data_provider.ConsumeBool()) {
 131          if (iter >= NUM_ITERS) break;
 132  
 133          // Make sure txns only have one input, and that a unique input is given to avoid circular references
 134          CMutableTransaction parent;
 135          parent.vin.resize(1);
 136          parent.vin[0].prevout = g_outpoints.at(iter++);
 137          parent.vout.emplace_back(0, CScript());
 138  
 139          mempool_txs.emplace_back(parent);
 140          const auto parent_entry = ConsumeTxMemPoolEntry(fuzzed_data_provider, mempool_txs.back());
 141          running_vsize_total += parent_entry.GetTxSize();
 142          if (running_vsize_total * WITNESS_SCALE_FACTOR > std::numeric_limits<int32_t>::max()) {
 143              // We aren't adding this final tx to mempool, so we don't want to conflict with it
 144              mempool_txs.pop_back();
 145              break;
 146          }
 147          assert(!pool.GetIter(parent_entry.GetTx().GetHash()));
 148          TryAddToMempool(pool, parent_entry);
 149  
 150          // It's possible that adding this to the mempool failed due to cluster
 151          // size limits; if so bail out.
 152          if(!pool.GetIter(parent_entry.GetTx().GetHash())) {
 153              mempool_txs.pop_back();
 154              continue;
 155          }
 156  
 157          child.vin[0].prevout = COutPoint{mempool_txs.back().GetHash(), 0};
 158          mempool_txs.emplace_back(child);
 159          const auto child_entry = ConsumeTxMemPoolEntry(fuzzed_data_provider, mempool_txs.back());
 160          running_vsize_total += child_entry.GetTxSize();
 161          if (running_vsize_total * WITNESS_SCALE_FACTOR > std::numeric_limits<int32_t>::max()) {
 162              // We aren't adding this final tx to mempool, so we don't want to conflict with it
 163              mempool_txs.pop_back();
 164              break;
 165          }
 166          if (!pool.GetIter(child_entry.GetTx().GetHash())) {
 167              TryAddToMempool(pool, child_entry);
 168              // Adding this transaction to the mempool may fail due to cluster
 169              // size limits; if so bail out.
 170              if(!pool.GetIter(child_entry.GetTx().GetHash())) {
 171                  mempool_txs.pop_back();
 172                  continue;
 173              }
 174          }
 175  
 176          if (fuzzed_data_provider.ConsumeBool()) {
 177              pool.PrioritiseTransaction(mempool_txs.back().GetHash(), fuzzed_data_provider.ConsumeIntegralInRange<int32_t>(-100000, 100000));
 178          }
 179      }
 180  
 181      // Pick some transactions at random to be the direct conflicts
 182      CTxMemPool::setEntries direct_conflicts;
 183      for (auto& tx : mempool_txs) {
 184          if (fuzzed_data_provider.ConsumeBool() && pool.GetIter(tx.GetHash())) {
 185              direct_conflicts.insert(*pool.GetIter(tx.GetHash()));
 186          }
 187      }
 188  
 189      // Calculate all conflicts:
 190      CTxMemPool::setEntries all_conflicts;
 191      for (auto& txiter : direct_conflicts) {
 192          pool.CalculateDescendants(txiter, all_conflicts);
 193      }
 194  
 195      CAmount replacement_fees = ConsumeMoney(fuzzed_data_provider);
 196      auto changeset = pool.GetChangeSet();
 197      for (auto& txiter : all_conflicts) {
 198          changeset->StageRemoval(txiter);
 199      }
 200      changeset->StageAddition(replacement_entry.GetSharedTx(), replacement_fees,
 201              replacement_entry.GetTime().count(), replacement_entry.GetHeight(),
 202              replacement_entry.GetSequence(), replacement_entry.GetSpendsCoinbase(),
 203              replacement_entry.GetSigOpCost(), replacement_entry.GetLockPoints());
 204      // Calculate the chunks for a replacement.
 205      auto calc_results{changeset->CalculateChunksForRBF()};
 206  
 207      if (calc_results.has_value()) {
 208          // Sanity checks on the chunks.
 209  
 210          // Feerates are monotonically decreasing.
 211          FeeFrac first_sum;
 212          for (size_t i = 0; i < calc_results->first.size(); ++i) {
 213              first_sum += calc_results->first[i];
 214              if (i) assert(ByRatio{calc_results->first[i - 1]} >= ByRatio{calc_results->first[i]});
 215          }
 216          FeeFrac second_sum;
 217          for (size_t i = 0; i < calc_results->second.size(); ++i) {
 218              second_sum += calc_results->second[i];
 219              if (i) assert(ByRatio{calc_results->second[i - 1]} >= ByRatio{calc_results->second[i]});
 220          }
 221  
 222          FeeFrac replaced;
 223          for (auto txiter : all_conflicts) {
 224              replaced.fee += txiter->GetModifiedFee();
 225              replaced.size += txiter->GetAdjustedWeight();
 226          }
 227          // The total fee & size of the new diagram minus replaced fee & size should be the total
 228          // fee & size of the old diagram minus replacement fee & size.
 229          assert((first_sum - replaced) == (second_sum - FeeFrac{replacement_fees, replacement_weight}));
 230      }
 231  
 232      // If internals report error, wrapper should too
 233      auto err_tuple{ImprovesFeerateDiagram(*changeset)};
 234      if (!calc_results.has_value()) {
 235           assert(err_tuple.value().first == DiagramCheckError::UNCALCULABLE);
 236      } else {
 237          // Diagram check succeeded
 238          auto old_sum = std::accumulate(calc_results->first.begin(), calc_results->first.end(), FeeFrac{});
 239          auto new_sum = std::accumulate(calc_results->second.begin(), calc_results->second.end(), FeeFrac{});
 240          if (!err_tuple.has_value()) {
 241              // New diagram's final fee should always match or exceed old diagram's
 242              assert(old_sum.fee <= new_sum.fee);
 243          } else if (old_sum.fee > new_sum.fee) {
 244              // Or it failed, and if old diagram had higher fees, it should be a failure
 245              assert(err_tuple.value().first == DiagramCheckError::FAILURE);
 246          }
 247      }
 248  }
 249