1  #include <blockencodings.h>
  2  #include <consensus/merkle.h>
  3  #include <consensus/validation.h>
  4  #include <primitives/block.h>
  5  #include <primitives/transaction.h>
  6  #include <test/fuzz/FuzzedDataProvider.h>
  7  #include <test/fuzz/fuzz.h>
  8  #include <test/fuzz/util.h>
  9  #include <test/fuzz/util/mempool.h>
 10  #include <test/util/setup_common.h>
 11  #include <test/util/txmempool.h>
 12  #include <txmempool.h>
 13  
 14  #include <cstddef>
 15  #include <cstdint>
 16  #include <limits>
 17  #include <memory>
 18  #include <optional>
 19  #include <set>
 20  #include <vector>
 21  
 22  namespace {
 23  const TestingSetup* g_setup;
 24  } // namespace
 25  
 26  void initialize_pdb()
 27  {
 28      static const auto testing_setup = MakeNoLogFileContext<const TestingSetup>();
 29      g_setup = testing_setup.get();
 30  }
 31  
 32  PartiallyDownloadedBlock::CheckBlockFn FuzzedCheckBlock(std::optional<BlockValidationResult> result)
 33  {
 34      return [result](const CBlock&, BlockValidationState& state, const Consensus::Params&, bool, bool) {
 35          if (result) {
 36              return state.Invalid(*result);
 37          }
 38  
 39          return true;
 40      };
 41  }
 42  
 43  FUZZ_TARGET(partially_downloaded_block, .init = initialize_pdb)
 44  {
 45      FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
 46  
 47      auto block{ConsumeDeserializable<CBlock>(fuzzed_data_provider, TX_WITH_WITNESS)};
 48      if (!block || block->vtx.size() == 0 ||
 49          block->vtx.size() >= std::numeric_limits<uint16_t>::max()) {
 50          return;
 51      }
 52  
 53      CBlockHeaderAndShortTxIDs cmpctblock{*block};
 54  
 55      CTxMemPool pool{MemPoolOptionsForTest(g_setup->m_node)};
 56      PartiallyDownloadedBlock pdb{&pool};
 57  
 58      // Set of available transactions (mempool or extra_txn)
 59      std::set<uint16_t> available;
 60      // The coinbase is always available
 61      available.insert(0);
 62  
 63      std::vector<std::pair<uint256, CTransactionRef>> extra_txn;
 64      for (size_t i = 1; i < block->vtx.size(); ++i) {
 65          auto tx{block->vtx[i]};
 66  
 67          bool add_to_extra_txn{fuzzed_data_provider.ConsumeBool()};
 68          bool add_to_mempool{fuzzed_data_provider.ConsumeBool()};
 69  
 70          if (add_to_extra_txn) {
 71              extra_txn.emplace_back(tx->GetWitnessHash(), tx);
 72              available.insert(i);
 73          }
 74  
 75          if (add_to_mempool) {
 76              LOCK2(cs_main, pool.cs);
 77              pool.addUnchecked(ConsumeTxMemPoolEntry(fuzzed_data_provider, *tx));
 78              available.insert(i);
 79          }
 80      }
 81  
 82      auto init_status{pdb.InitData(cmpctblock, extra_txn)};
 83  
 84      std::vector<CTransactionRef> missing;
 85      // Whether we skipped a transaction that should be included in `missing`.
 86      // FillBlock should never return READ_STATUS_OK if that is the case.
 87      bool skipped_missing{false};
 88      for (size_t i = 0; i < cmpctblock.BlockTxCount(); i++) {
 89          // If init_status == READ_STATUS_OK then a available transaction in the
 90          // compact block (i.e. IsTxAvailable(i) == true) implies that we marked
 91          // that transaction as available above (i.e. available.count(i) > 0).
 92          // The reverse is not true, due to possible compact block short id
 93          // collisions (i.e. available.count(i) > 0 does not imply
 94          // IsTxAvailable(i) == true).
 95          if (init_status == READ_STATUS_OK) {
 96              assert(!pdb.IsTxAvailable(i) || available.count(i) > 0);
 97          }
 98  
 99          bool skip{fuzzed_data_provider.ConsumeBool()};
100          if (!pdb.IsTxAvailable(i) && !skip) {
101              missing.push_back(block->vtx[i]);
102          }
103  
104          skipped_missing |= (!pdb.IsTxAvailable(i) && skip);
105      }
106  
107      // Mock CheckBlock
108      bool fail_check_block{fuzzed_data_provider.ConsumeBool()};
109      auto validation_result =
110          fuzzed_data_provider.PickValueInArray(
111              {BlockValidationResult::BLOCK_RESULT_UNSET,
112               BlockValidationResult::BLOCK_CONSENSUS,
113               BlockValidationResult::BLOCK_RECENT_CONSENSUS_CHANGE,
114               BlockValidationResult::BLOCK_CACHED_INVALID,
115               BlockValidationResult::BLOCK_INVALID_HEADER,
116               BlockValidationResult::BLOCK_MUTATED,
117               BlockValidationResult::BLOCK_MISSING_PREV,
118               BlockValidationResult::BLOCK_INVALID_PREV,
119               BlockValidationResult::BLOCK_TIME_FUTURE,
120               BlockValidationResult::BLOCK_CHECKPOINT,
121               BlockValidationResult::BLOCK_HEADER_LOW_WORK});
122      pdb.m_check_block_mock = FuzzedCheckBlock(
123          fail_check_block ?
124              std::optional<BlockValidationResult>{validation_result} :
125              std::nullopt);
126  
127      CBlock reconstructed_block;
128      auto fill_status{pdb.FillBlock(reconstructed_block, missing)};
129      switch (fill_status) {
130      case READ_STATUS_OK:
131          assert(!skipped_missing);
132          assert(!fail_check_block);
133          assert(block->GetHash() == reconstructed_block.GetHash());
134          break;
135      case READ_STATUS_CHECKBLOCK_FAILED: [[fallthrough]];
136      case READ_STATUS_FAILED:
137          assert(fail_check_block);
138          break;
139      case READ_STATUS_INVALID:
140          break;
141      }
142  }