1 /* $NetBSD: hmac.c,v 1.5 2022/09/23 12:15:33 christos Exp $ */
2
3 /*
4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5 *
6 * SPDX-License-Identifier: MPL-2.0
7 *
8 * This Source Code Form is subject to the terms of the Mozilla Public
9 * License, v. 2.0. If a copy of the MPL was not distributed with this
10 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11 *
12 * See the COPYRIGHT file distributed with this work for additional
13 * information regarding copyright ownership.
14 */
15
16 #include <openssl/hmac.h>
17 #include <openssl/opensslv.h>
18
19 #include <isc/assertions.h>
20 #include <isc/hmac.h>
21 #include <isc/md.h>
22 #include <isc/platform.h>
23 #include <isc/safe.h>
24 #include <isc/string.h>
25 #include <isc/types.h>
26 #include <isc/util.h>
27
28 #include "openssl_shim.h"
29
30 isc_hmac_t *
isc_hmac_new(void)31 isc_hmac_new(void) {
32 HMAC_CTX *hmac = HMAC_CTX_new();
33 RUNTIME_CHECK(hmac != NULL);
34 return ((struct hmac *)hmac);
35 }
36
37 void
isc_hmac_free(isc_hmac_t * hmac)38 isc_hmac_free(isc_hmac_t *hmac) {
39 if (ISC_UNLIKELY(hmac == NULL)) {
40 return;
41 }
42
43 HMAC_CTX_free(hmac);
44 }
45
46 isc_result_t
isc_hmac_init(isc_hmac_t * hmac,const void * key,size_t keylen,const isc_md_type_t * md_type)47 isc_hmac_init(isc_hmac_t *hmac, const void *key, size_t keylen,
48 const isc_md_type_t *md_type) {
49 REQUIRE(hmac != NULL);
50 REQUIRE(key != NULL);
51
52 if (md_type == NULL) {
53 return (ISC_R_NOTIMPLEMENTED);
54 }
55
56 if (HMAC_Init_ex(hmac, key, keylen, md_type, NULL) != 1) {
57 return (ISC_R_CRYPTOFAILURE);
58 }
59
60 return (ISC_R_SUCCESS);
61 }
62
63 isc_result_t
isc_hmac_reset(isc_hmac_t * hmac)64 isc_hmac_reset(isc_hmac_t *hmac) {
65 REQUIRE(hmac != NULL);
66
67 if (HMAC_CTX_reset(hmac) != 1) {
68 return (ISC_R_CRYPTOFAILURE);
69 }
70
71 return (ISC_R_SUCCESS);
72 }
73
74 isc_result_t
isc_hmac_update(isc_hmac_t * hmac,const unsigned char * buf,const size_t len)75 isc_hmac_update(isc_hmac_t *hmac, const unsigned char *buf, const size_t len) {
76 REQUIRE(hmac != NULL);
77
78 if (ISC_UNLIKELY(buf == NULL || len == 0)) {
79 return (ISC_R_SUCCESS);
80 }
81
82 if (HMAC_Update(hmac, buf, len) != 1) {
83 return (ISC_R_CRYPTOFAILURE);
84 }
85
86 return (ISC_R_SUCCESS);
87 }
88
89 isc_result_t
isc_hmac_final(isc_hmac_t * hmac,unsigned char * digest,unsigned int * digestlen)90 isc_hmac_final(isc_hmac_t *hmac, unsigned char *digest,
91 unsigned int *digestlen) {
92 REQUIRE(hmac != NULL);
93 REQUIRE(digest != NULL);
94
95 if (HMAC_Final(hmac, digest, digestlen) != 1) {
96 return (ISC_R_CRYPTOFAILURE);
97 }
98
99 return (ISC_R_SUCCESS);
100 }
101
102 const isc_md_type_t *
isc_hmac_get_md_type(isc_hmac_t * hmac)103 isc_hmac_get_md_type(isc_hmac_t *hmac) {
104 REQUIRE(hmac != NULL);
105
106 return (HMAC_CTX_get_md(hmac));
107 }
108
109 size_t
isc_hmac_get_size(isc_hmac_t * hmac)110 isc_hmac_get_size(isc_hmac_t *hmac) {
111 REQUIRE(hmac != NULL);
112
113 return ((size_t)EVP_MD_size(HMAC_CTX_get_md(hmac)));
114 }
115
116 int
isc_hmac_get_block_size(isc_hmac_t * hmac)117 isc_hmac_get_block_size(isc_hmac_t *hmac) {
118 REQUIRE(hmac != NULL);
119
120 return (EVP_MD_block_size(HMAC_CTX_get_md(hmac)));
121 }
122
123 isc_result_t
isc_hmac(const isc_md_type_t * type,const void * key,const int keylen,const unsigned char * buf,const size_t len,unsigned char * digest,unsigned int * digestlen)124 isc_hmac(const isc_md_type_t *type, const void *key, const int keylen,
125 const unsigned char *buf, const size_t len, unsigned char *digest,
126 unsigned int *digestlen) {
127 isc_result_t res;
128 isc_hmac_t *hmac = isc_hmac_new();
129
130 res = isc_hmac_init(hmac, key, keylen, type);
131 if (res != ISC_R_SUCCESS) {
132 goto end;
133 }
134
135 res = isc_hmac_update(hmac, buf, len);
136 if (res != ISC_R_SUCCESS) {
137 goto end;
138 }
139
140 res = isc_hmac_final(hmac, digest, digestlen);
141 if (res != ISC_R_SUCCESS) {
142 goto end;
143 }
144 end:
145 isc_hmac_free(hmac);
146
147 return (res);
148 }
149