| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "crypto/ec_signature_creator_impl.h" |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include "crypto/ec_private_key.h" |
| #include "crypto/openssl_util.h" |
| #include "third_party/boringssl/src/include/openssl/bn.h" |
| #include "third_party/boringssl/src/include/openssl/ec.h" |
| #include "third_party/boringssl/src/include/openssl/ecdsa.h" |
| #include "third_party/boringssl/src/include/openssl/evp.h" |
| #include "third_party/boringssl/src/include/openssl/sha.h" |
| |
| namespace crypto { |
| |
| ECSignatureCreatorImpl::ECSignatureCreatorImpl(ECPrivateKey* key) |
| : key_(key) { |
| EnsureOpenSSLInit(); |
| } |
| |
| ECSignatureCreatorImpl::~ECSignatureCreatorImpl() = default; |
| |
| bool ECSignatureCreatorImpl::Sign(const uint8_t* data, |
| int data_len, |
| std::vector<uint8_t>* signature) { |
| OpenSSLErrStackTracer err_tracer(FROM_HERE); |
| bssl::ScopedEVP_MD_CTX ctx; |
| size_t sig_len = 0; |
| if (!ctx.get() || |
| !EVP_DigestSignInit(ctx.get(), nullptr, EVP_sha256(), nullptr, |
| key_->key()) || |
| !EVP_DigestSignUpdate(ctx.get(), data, data_len) || |
| !EVP_DigestSignFinal(ctx.get(), nullptr, &sig_len)) { |
| return false; |
| } |
| |
| signature->resize(sig_len); |
| if (!EVP_DigestSignFinal(ctx.get(), &signature->front(), &sig_len)) |
| return false; |
| |
| // NOTE: A call to EVP_DigestSignFinal() with a nullptr second parameter |
| // returns a maximum allocation size, while the call without a nullptr |
| // returns the real one, which may be smaller. |
| signature->resize(sig_len); |
| return true; |
| } |
| |
| bool ECSignatureCreatorImpl::DecodeSignature( |
| const std::vector<uint8_t>& der_sig, |
| std::vector<uint8_t>* out_raw_sig) { |
| OpenSSLErrStackTracer err_tracer(FROM_HERE); |
| // Create ECDSA_SIG object from DER-encoded data. |
| bssl::UniquePtr<ECDSA_SIG> ecdsa_sig( |
| ECDSA_SIG_from_bytes(der_sig.data(), der_sig.size())); |
| if (!ecdsa_sig.get()) |
| return false; |
| |
| // The result is made of two 32-byte vectors. |
| const size_t kMaxBytesPerBN = 32; |
| std::vector<uint8_t> result(2 * kMaxBytesPerBN); |
| |
| if (!BN_bn2bin_padded(&result[0], kMaxBytesPerBN, ecdsa_sig->r) || |
| !BN_bn2bin_padded(&result[kMaxBytesPerBN], kMaxBytesPerBN, |
| ecdsa_sig->s)) { |
| return false; |
| } |
| out_raw_sig->swap(result); |
| return true; |
| } |
| |
| } // namespace crypto |