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 <crypto/poly1305.h>
 6  #include <test/fuzz/FuzzedDataProvider.h>
 7  #include <test/fuzz/fuzz.h>
 8  #include <test/fuzz/util.h>
 9  
10  #include <cstdint>
11  #include <vector>
12  
13  FUZZ_TARGET(crypto_poly1305)
14  {
15      FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
16  
17      const auto key = ConsumeFixedLengthByteVector<std::byte>(fuzzed_data_provider, Poly1305::KEYLEN);
18      const auto in = ConsumeRandomLengthByteVector<std::byte>(fuzzed_data_provider);
19  
20      std::vector<std::byte> tag_out(Poly1305::TAGLEN);
21      Poly1305{key}.Update(in).Finalize(tag_out);
22  }
23  
24  FUZZ_TARGET(crypto_poly1305_split)
25  {
26      FuzzedDataProvider provider{buffer.data(), buffer.size()};
27  
28      // Read key and instantiate two Poly1305 objects with it.
29      auto key = provider.ConsumeBytes<std::byte>(Poly1305::KEYLEN);
30      key.resize(Poly1305::KEYLEN);
31      Poly1305 poly_full{key}, poly_split{key};
32  
33      // Vector that holds all bytes processed so far.
34      std::vector<std::byte> total_input;
35  
36      // Process input in pieces.
37      LIMITED_WHILE(provider.remaining_bytes(), 100) {
38          auto in = ConsumeRandomLengthByteVector<std::byte>(provider);
39          poly_split.Update(in);
40          // Update total_input to match what was processed.
41          total_input.insert(total_input.end(), in.begin(), in.end());
42      }
43  
44      // Process entire input at once.
45      poly_full.Update(total_input);
46  
47      // Verify both agree.
48      std::array<std::byte, Poly1305::TAGLEN> tag_split, tag_full;
49      poly_split.Finalize(tag_split);
50      poly_full.Finalize(tag_full);
51      assert(tag_full == tag_split);
52  }