1  // Copyright (c) 2009-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 <pubkey.h>
 6  #include <script/interpreter.h>
 7  #include <test/fuzz/FuzzedDataProvider.h>
 8  #include <test/fuzz/fuzz.h>
 9  #include <test/fuzz/util.h>
10  #include <test/util/script.h>
11  
12  #include <cstdint>
13  #include <limits>
14  #include <string>
15  #include <vector>
16  
17  namespace {
18  class FuzzedSignatureChecker : public BaseSignatureChecker
19  {
20      FuzzedDataProvider& m_fuzzed_data_provider;
21  
22  public:
23      explicit FuzzedSignatureChecker(FuzzedDataProvider& fuzzed_data_provider) : m_fuzzed_data_provider(fuzzed_data_provider)
24      {
25      }
26  
27      bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override
28      {
29          return m_fuzzed_data_provider.ConsumeBool();
30      }
31  
32      bool CheckSchnorrSignature(std::span<const unsigned char> sig, std::span<const unsigned char> pubkey, SigVersion sigversion, ScriptExecutionData& execdata, ScriptError* serror = nullptr) const override
33      {
34          return m_fuzzed_data_provider.ConsumeBool();
35      }
36  
37      bool CheckLockTime(const CScriptNum& nLockTime) const override
38      {
39          return m_fuzzed_data_provider.ConsumeBool();
40      }
41  
42      bool CheckSequence(const CScriptNum& nSequence) const override
43      {
44          return m_fuzzed_data_provider.ConsumeBool();
45      }
46  
47      virtual ~FuzzedSignatureChecker() = default;
48  };
49  } // namespace
50  
51  FUZZ_TARGET(signature_checker)
52  {
53      FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
54      const auto flags = script_verify_flags::from_int(fuzzed_data_provider.ConsumeIntegral<script_verify_flags::value_type>());
55      const SigVersion sig_version = fuzzed_data_provider.PickValueInArray({SigVersion::BASE, SigVersion::WITNESS_V0});
56      const auto script_1{ConsumeScript(fuzzed_data_provider)};
57      const auto script_2{ConsumeScript(fuzzed_data_provider)};
58      std::vector<std::vector<unsigned char>> stack;
59      (void)EvalScript(stack, script_1, flags, FuzzedSignatureChecker(fuzzed_data_provider), sig_version, nullptr);
60      if (!IsValidFlagCombination(flags)) {
61          return;
62      }
63      (void)VerifyScript(script_1, script_2, nullptr, flags, FuzzedSignatureChecker(fuzzed_data_provider), nullptr);
64  }