blob: 7d4843842668baa0ed9fafc278dafe4c8f146d80 [file] [log] [blame]
// Copyright (c) 2011 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/signature_verifier.h"
#include "base/check_op.h"
#include "crypto/openssl_util.h"
#include "third_party/boringssl/src/include/openssl/bytestring.h"
#include "third_party/boringssl/src/include/openssl/digest.h"
#include "third_party/boringssl/src/include/openssl/evp.h"
#include "third_party/boringssl/src/include/openssl/rsa.h"
namespace crypto {
struct SignatureVerifier::VerifyContext {
bssl::ScopedEVP_MD_CTX ctx;
};
SignatureVerifier::SignatureVerifier() = default;
SignatureVerifier::~SignatureVerifier() = default;
bool SignatureVerifier::VerifyInit(SignatureAlgorithm signature_algorithm,
base::span<const uint8_t> signature,
base::span<const uint8_t> public_key_info) {
OpenSSLErrStackTracer err_tracer(FROM_HERE);
int pkey_type = EVP_PKEY_NONE;
const EVP_MD* digest = nullptr;
switch (signature_algorithm) {
case RSA_PKCS1_SHA1:
pkey_type = EVP_PKEY_RSA;
digest = EVP_sha1();
break;
case RSA_PKCS1_SHA256:
case RSA_PSS_SHA256:
pkey_type = EVP_PKEY_RSA;
digest = EVP_sha256();
break;
case ECDSA_SHA256:
pkey_type = EVP_PKEY_EC;
digest = EVP_sha256();
break;
}
DCHECK_NE(EVP_PKEY_NONE, pkey_type);
DCHECK(digest);
if (verify_context_)
return false;
verify_context_.reset(new VerifyContext);
signature_.assign(signature.data(), signature.data() + signature.size());
CBS cbs;
CBS_init(&cbs, public_key_info.data(), public_key_info.size());
bssl::UniquePtr<EVP_PKEY> public_key(EVP_parse_public_key(&cbs));
if (!public_key || CBS_len(&cbs) != 0 ||
EVP_PKEY_id(public_key.get()) != pkey_type) {
return false;
}
EVP_PKEY_CTX* pkey_ctx;
if (!EVP_DigestVerifyInit(verify_context_->ctx.get(), &pkey_ctx, digest,
nullptr, public_key.get())) {
return false;
}
if (signature_algorithm == RSA_PSS_SHA256) {
if (!EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING) ||
!EVP_PKEY_CTX_set_rsa_mgf1_md(pkey_ctx, digest) ||
!EVP_PKEY_CTX_set_rsa_pss_saltlen(
pkey_ctx, -1 /* match digest and salt length */)) {
return false;
}
}
return true;
}
void SignatureVerifier::VerifyUpdate(base::span<const uint8_t> data_part) {
DCHECK(verify_context_);
OpenSSLErrStackTracer err_tracer(FROM_HERE);
int rv = EVP_DigestVerifyUpdate(verify_context_->ctx.get(), data_part.data(),
data_part.size());
DCHECK_EQ(rv, 1);
}
bool SignatureVerifier::VerifyFinal() {
DCHECK(verify_context_);
OpenSSLErrStackTracer err_tracer(FROM_HERE);
int rv = EVP_DigestVerifyFinal(verify_context_->ctx.get(), signature_.data(),
signature_.size());
DCHECK_EQ(static_cast<int>(!!rv), rv);
Reset();
return rv == 1;
}
void SignatureVerifier::Reset() {
verify_context_.reset();
signature_.clear();
}
} // namespace crypto