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