1 /*
2 * Copyright 2004 The WebRTC Project Authors. All rights reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "rtc_base/openssl_digest.h"
12
13 #include "rtc_base/checks.h" // RTC_DCHECK, RTC_CHECK
14 #include "rtc_base/openssl.h"
15
16 namespace rtc {
17
OpenSSLDigest(const std::string & algorithm)18 OpenSSLDigest::OpenSSLDigest(const std::string& algorithm) {
19 ctx_ = EVP_MD_CTX_new();
20 RTC_CHECK(ctx_ != nullptr);
21 EVP_MD_CTX_init(ctx_);
22 if (GetDigestEVP(algorithm, &md_)) {
23 EVP_DigestInit_ex(ctx_, md_, nullptr);
24 } else {
25 md_ = nullptr;
26 }
27 }
28
~OpenSSLDigest()29 OpenSSLDigest::~OpenSSLDigest() {
30 EVP_MD_CTX_destroy(ctx_);
31 }
32
Size() const33 size_t OpenSSLDigest::Size() const {
34 if (!md_) {
35 return 0;
36 }
37 return EVP_MD_size(md_);
38 }
39
Update(const void * buf,size_t len)40 void OpenSSLDigest::Update(const void* buf, size_t len) {
41 if (!md_) {
42 return;
43 }
44 EVP_DigestUpdate(ctx_, buf, len);
45 }
46
Finish(void * buf,size_t len)47 size_t OpenSSLDigest::Finish(void* buf, size_t len) {
48 if (!md_ || len < Size()) {
49 return 0;
50 }
51 unsigned int md_len;
52 EVP_DigestFinal_ex(ctx_, static_cast<unsigned char*>(buf), &md_len);
53 EVP_DigestInit_ex(ctx_, md_, nullptr); // prepare for future Update()s
54 RTC_DCHECK(md_len == Size());
55 return md_len;
56 }
57
GetDigestEVP(const std::string & algorithm,const EVP_MD ** mdp)58 bool OpenSSLDigest::GetDigestEVP(const std::string& algorithm,
59 const EVP_MD** mdp) {
60 const EVP_MD* md;
61 if (algorithm == DIGEST_MD5) {
62 md = EVP_md5();
63 } else if (algorithm == DIGEST_SHA_1) {
64 md = EVP_sha1();
65 } else if (algorithm == DIGEST_SHA_224) {
66 md = EVP_sha224();
67 } else if (algorithm == DIGEST_SHA_256) {
68 md = EVP_sha256();
69 } else if (algorithm == DIGEST_SHA_384) {
70 md = EVP_sha384();
71 } else if (algorithm == DIGEST_SHA_512) {
72 md = EVP_sha512();
73 } else {
74 return false;
75 }
76
77 // Can't happen
78 RTC_DCHECK(EVP_MD_size(md) >= 16);
79 *mdp = md;
80 return true;
81 }
82
GetDigestName(const EVP_MD * md,std::string * algorithm)83 bool OpenSSLDigest::GetDigestName(const EVP_MD* md, std::string* algorithm) {
84 RTC_DCHECK(md != nullptr);
85 RTC_DCHECK(algorithm != nullptr);
86
87 int md_type = EVP_MD_type(md);
88 if (md_type == NID_md5) {
89 *algorithm = DIGEST_MD5;
90 } else if (md_type == NID_sha1) {
91 *algorithm = DIGEST_SHA_1;
92 } else if (md_type == NID_sha224) {
93 *algorithm = DIGEST_SHA_224;
94 } else if (md_type == NID_sha256) {
95 *algorithm = DIGEST_SHA_256;
96 } else if (md_type == NID_sha384) {
97 *algorithm = DIGEST_SHA_384;
98 } else if (md_type == NID_sha512) {
99 *algorithm = DIGEST_SHA_512;
100 } else {
101 algorithm->clear();
102 return false;
103 }
104
105 return true;
106 }
107
GetDigestSize(const std::string & algorithm,size_t * length)108 bool OpenSSLDigest::GetDigestSize(const std::string& algorithm,
109 size_t* length) {
110 const EVP_MD* md;
111 if (!GetDigestEVP(algorithm, &md))
112 return false;
113
114 *length = EVP_MD_size(md);
115 return true;
116 }
117
118 } // namespace rtc
119