1 // Copyright 2012 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "crypto/ec_signature_creator_impl.h"
10 #include "crypto/ec_private_key.h"
11 #include "crypto/openssl_util.h"
12 #include "third_party/boringssl/src/include/openssl/bn.h"
13 #include "third_party/boringssl/src/include/openssl/ec.h"
14 #include "third_party/boringssl/src/include/openssl/ecdsa.h"
15 #include "third_party/boringssl/src/include/openssl/evp.h"
16 #include "third_party/boringssl/src/include/openssl/sha.h"
20 ECSignatureCreatorImpl::ECSignatureCreatorImpl(ECPrivateKey* key)
25 ECSignatureCreatorImpl::~ECSignatureCreatorImpl() = default;
27 bool ECSignatureCreatorImpl::Sign(base::span<const uint8_t> data,
28 std::vector<uint8_t>* signature) {
29 OpenSSLErrStackTracer err_tracer(FROM_HERE);
30 bssl::ScopedEVP_MD_CTX ctx;
33 !EVP_DigestSignInit(ctx.get(), nullptr, EVP_sha256(), nullptr,
35 !EVP_DigestSignUpdate(ctx.get(), data.data(), data.size()) ||
36 !EVP_DigestSignFinal(ctx.get(), nullptr, &sig_len)) {
40 signature->resize(sig_len);
41 if (!EVP_DigestSignFinal(ctx.get(), &signature->front(), &sig_len))
44 // NOTE: A call to EVP_DigestSignFinal() with a nullptr second parameter
45 // returns a maximum allocation size, while the call without a nullptr
46 // returns the real one, which may be smaller.
47 signature->resize(sig_len);
51 bool ECSignatureCreatorImpl::DecodeSignature(
52 const std::vector<uint8_t>& der_sig,
53 std::vector<uint8_t>* out_raw_sig) {
54 OpenSSLErrStackTracer err_tracer(FROM_HERE);
55 // Create ECDSA_SIG object from DER-encoded data.
56 bssl::UniquePtr<ECDSA_SIG> ecdsa_sig(
57 ECDSA_SIG_from_bytes(der_sig.data(), der_sig.size()));
61 // The result is made of two 32-byte vectors.
62 const size_t kMaxBytesPerBN = 32;
63 std::vector<uint8_t> result(2 * kMaxBytesPerBN);
65 if (!BN_bn2bin_padded(&result[0], kMaxBytesPerBN, ecdsa_sig->r) ||
66 !BN_bn2bin_padded(&result[kMaxBytesPerBN], kMaxBytesPerBN,
70 out_raw_sig->swap(result);