1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "crypto/signature_creator.h"
6
7#include <openssl/evp.h>
8#include <openssl/rsa.h>
9
10#include "base/logging.h"
11#include "base/memory/scoped_ptr.h"
12#include "base/stl_util.h"
13#include "crypto/openssl_util.h"
14#include "crypto/rsa_private_key.h"
15
16namespace crypto {
17
18// static
19SignatureCreator* SignatureCreator::Create(RSAPrivateKey* key) {
20  OpenSSLErrStackTracer err_tracer(FROM_HERE);
21  scoped_ptr<SignatureCreator> result(new SignatureCreator);
22  result->key_ = key;
23  if (!EVP_SignInit_ex(result->sign_context_, EVP_sha1(), NULL))
24    return NULL;
25  return result.release();
26}
27
28// static
29bool SignatureCreator::Sign(RSAPrivateKey* key,
30                            const uint8* data,
31                            int data_len,
32                            std::vector<uint8>* signature) {
33  RSA* rsa_key = EVP_PKEY_get1_RSA(key->key());
34  if (!rsa_key)
35    return false;
36  signature->resize(RSA_size(rsa_key));
37
38  unsigned int len = 0;
39  bool success = RSA_sign(NID_sha1, data, data_len, vector_as_array(signature),
40                          &len, rsa_key);
41  if (!success) {
42    signature->clear();
43    return false;
44  }
45  signature->resize(len);
46  return true;
47}
48
49SignatureCreator::SignatureCreator()
50    : sign_context_(EVP_MD_CTX_create()) {
51}
52
53SignatureCreator::~SignatureCreator() {
54  EVP_MD_CTX_destroy(sign_context_);
55}
56
57bool SignatureCreator::Update(const uint8* data_part, int data_part_len) {
58  OpenSSLErrStackTracer err_tracer(FROM_HERE);
59  return EVP_SignUpdate(sign_context_, data_part, data_part_len) == 1;
60}
61
62bool SignatureCreator::Final(std::vector<uint8>* signature) {
63  OpenSSLErrStackTracer err_tracer(FROM_HERE);
64  EVP_PKEY* key = key_->key();
65  signature->resize(EVP_PKEY_size(key));
66
67  unsigned int len = 0;
68  int rv = EVP_SignFinal(sign_context_, vector_as_array(signature), &len, key);
69  if (!rv) {
70    signature->clear();
71    return false;
72  }
73  signature->resize(len);
74  return true;
75}
76
77}  // namespace crypto
78