1 // Copyright (c) 2020 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 <key.h>
6 #include <secp256k1.h>
7 #include <test/fuzz/FuzzedDataProvider.h>
8 #include <test/fuzz/fuzz.h>
9 #include <test/fuzz/util.h>
10 
11 #include <cstdint>
12 #include <vector>
13 
14 bool SigHasLowR(const secp256k1_ecdsa_signature* sig);
15 int ecdsa_signature_parse_der_lax(const secp256k1_context* ctx, secp256k1_ecdsa_signature* sig, const unsigned char* input, size_t inputlen);
16 
test_one_input(const std::vector<uint8_t> & buffer)17 void test_one_input(const std::vector<uint8_t>& buffer)
18 {
19     FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
20     const std::vector<uint8_t> signature_bytes = ConsumeRandomLengthByteVector(fuzzed_data_provider);
21     if (signature_bytes.data() == nullptr) {
22         return;
23     }
24     secp256k1_context* secp256k1_context_verify = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY);
25     secp256k1_ecdsa_signature sig_der_lax;
26     const bool parsed_der_lax = ecdsa_signature_parse_der_lax(secp256k1_context_verify, &sig_der_lax, signature_bytes.data(), signature_bytes.size()) == 1;
27     if (parsed_der_lax) {
28         ECC_Start();
29         (void)SigHasLowR(&sig_der_lax);
30         ECC_Stop();
31     }
32     secp256k1_context_destroy(secp256k1_context_verify);
33 }
34