/ src / test / fuzz / script.cpp
script.cpp
  1  // Copyright (c) 2019-2022 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 <chainparams.h>
  6  #include <compressor.h>
  7  #include <core_io.h>
  8  #include <core_memusage.h>
  9  #include <key_io.h>
 10  #include <policy/policy.h>
 11  #include <pubkey.h>
 12  #include <rpc/util.h>
 13  #include <script/descriptor.h>
 14  #include <script/interpreter.h>
 15  #include <script/script.h>
 16  #include <script/script_error.h>
 17  #include <script/sign.h>
 18  #include <script/signingprovider.h>
 19  #include <script/solver.h>
 20  #include <streams.h>
 21  #include <test/fuzz/FuzzedDataProvider.h>
 22  #include <test/fuzz/fuzz.h>
 23  #include <test/fuzz/util.h>
 24  #include <univalue.h>
 25  #include <util/chaintype.h>
 26  
 27  #include <algorithm>
 28  #include <cassert>
 29  #include <cstdint>
 30  #include <optional>
 31  #include <string>
 32  #include <vector>
 33  
 34  void initialize_script()
 35  {
 36      SelectParams(ChainType::REGTEST);
 37  }
 38  
 39  FUZZ_TARGET(script, .init = initialize_script)
 40  {
 41      FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
 42      const CScript script{ConsumeScript(fuzzed_data_provider)};
 43  
 44      CompressedScript compressed;
 45      if (CompressScript(script, compressed)) {
 46          const unsigned int size = compressed[0];
 47          compressed.erase(compressed.begin());
 48          assert(size <= 5);
 49          CScript decompressed_script;
 50          const bool ok = DecompressScript(decompressed_script, size, compressed);
 51          assert(ok);
 52          assert(script == decompressed_script);
 53      }
 54  
 55      TxoutType which_type;
 56      bool is_standard_ret = IsStandard(script, std::nullopt, which_type);
 57      if (!is_standard_ret) {
 58          assert(which_type == TxoutType::NONSTANDARD ||
 59                 which_type == TxoutType::NULL_DATA ||
 60                 which_type == TxoutType::MULTISIG);
 61      }
 62      if (which_type == TxoutType::NONSTANDARD) {
 63          assert(!is_standard_ret);
 64      }
 65      if (which_type == TxoutType::NULL_DATA) {
 66          assert(script.IsUnspendable());
 67      }
 68      if (script.IsUnspendable()) {
 69          assert(which_type == TxoutType::NULL_DATA ||
 70                 which_type == TxoutType::NONSTANDARD);
 71      }
 72  
 73      CTxDestination address;
 74      bool extract_destination_ret = ExtractDestination(script, address);
 75      if (!extract_destination_ret) {
 76          assert(which_type == TxoutType::PUBKEY ||
 77                 which_type == TxoutType::NONSTANDARD ||
 78                 which_type == TxoutType::NULL_DATA ||
 79                 which_type == TxoutType::MULTISIG);
 80      }
 81      if (which_type == TxoutType::NONSTANDARD ||
 82          which_type == TxoutType::NULL_DATA ||
 83          which_type == TxoutType::MULTISIG) {
 84          assert(!extract_destination_ret);
 85      }
 86  
 87      const FlatSigningProvider signing_provider;
 88      (void)InferDescriptor(script, signing_provider);
 89      (void)IsSegWitOutput(signing_provider, script);
 90  
 91      (void)RecursiveDynamicUsage(script);
 92  
 93      std::vector<std::vector<unsigned char>> solutions;
 94      (void)Solver(script, solutions);
 95  
 96      (void)script.HasValidOps();
 97      (void)script.IsPayToScriptHash();
 98      (void)script.IsPayToWitnessScriptHash();
 99      (void)script.IsPushOnly();
100      (void)script.GetSigOpCount(/* fAccurate= */ false);
101  
102      {
103          const std::vector<uint8_t> bytes = ConsumeRandomLengthByteVector(fuzzed_data_provider);
104          CompressedScript compressed_script;
105          compressed_script.assign(bytes.begin(), bytes.end());
106          // DecompressScript(..., ..., bytes) is not guaranteed to be defined if the bytes vector is too short
107          if (compressed_script.size() >= 32) {
108              CScript decompressed_script;
109              DecompressScript(decompressed_script, fuzzed_data_provider.ConsumeIntegral<unsigned int>(), compressed_script);
110          }
111      }
112  
113      const std::optional<CScript> other_script = ConsumeDeserializable<CScript>(fuzzed_data_provider);
114      if (other_script) {
115          {
116              CScript script_mut{script};
117              (void)FindAndDelete(script_mut, *other_script);
118          }
119          const std::vector<std::string> random_string_vector = ConsumeRandomLengthStringVector(fuzzed_data_provider);
120          const uint32_t u32{fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
121          const uint32_t flags{u32 | SCRIPT_VERIFY_P2SH};
122          {
123              CScriptWitness wit;
124              for (const auto& s : random_string_vector) {
125                  wit.stack.emplace_back(s.begin(), s.end());
126              }
127              (void)CountWitnessSigOps(script, *other_script, &wit, flags);
128              wit.SetNull();
129          }
130      }
131  
132      (void)GetOpName(ConsumeOpcodeType(fuzzed_data_provider));
133      (void)ScriptErrorString(static_cast<ScriptError>(fuzzed_data_provider.ConsumeIntegralInRange<int>(0, SCRIPT_ERR_ERROR_COUNT)));
134  
135      {
136          const std::vector<uint8_t> bytes = ConsumeRandomLengthByteVector(fuzzed_data_provider);
137          CScript append_script{bytes.begin(), bytes.end()};
138          append_script << fuzzed_data_provider.ConsumeIntegral<int64_t>();
139          append_script << ConsumeOpcodeType(fuzzed_data_provider);
140          append_script << CScriptNum{fuzzed_data_provider.ConsumeIntegral<int64_t>()};
141          append_script << ConsumeRandomLengthByteVector(fuzzed_data_provider);
142      }
143  
144      {
145          const CTxDestination tx_destination_1{
146              fuzzed_data_provider.ConsumeBool() ?
147                  DecodeDestination(fuzzed_data_provider.ConsumeRandomLengthString()) :
148                  ConsumeTxDestination(fuzzed_data_provider)};
149          const CTxDestination tx_destination_2{ConsumeTxDestination(fuzzed_data_provider)};
150          const std::string encoded_dest{EncodeDestination(tx_destination_1)};
151          const UniValue json_dest{DescribeAddress(tx_destination_1)};
152          (void)GetKeyForDestination(/*store=*/{}, tx_destination_1);
153          const CScript dest{GetScriptForDestination(tx_destination_1)};
154          const bool valid{IsValidDestination(tx_destination_1)};
155  
156          if (!std::get_if<PubKeyDestination>(&tx_destination_1)) {
157              // Only try to round trip non-pubkey destinations since PubKeyDestination has no encoding
158              Assert(dest.empty() != valid);
159              Assert(tx_destination_1 == DecodeDestination(encoded_dest));
160              Assert(valid == IsValidDestinationString(encoded_dest));
161          }
162  
163          (void)(tx_destination_1 < tx_destination_2);
164          if (tx_destination_1 == tx_destination_2) {
165              Assert(encoded_dest == EncodeDestination(tx_destination_2));
166              Assert(json_dest.write() == DescribeAddress(tx_destination_2).write());
167              Assert(dest == GetScriptForDestination(tx_destination_2));
168          }
169      }
170  }