xref: /openbsd/lib/libcrypto/hmac/hm_pmeth.c (revision 4600b3a1)
1 /* $OpenBSD: hm_pmeth.c,v 1.17 2023/12/28 22:00:56 tb Exp $ */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project 2007.
4  */
5 /* ====================================================================
6  * Copyright (c) 2007 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 #include <stdio.h>
60 #include <string.h>
61 
62 #include <openssl/evp.h>
63 #include <openssl/hmac.h>
64 #include <openssl/x509.h>
65 #include <openssl/x509v3.h>
66 
67 #include "evp_local.h"
68 #include "hmac_local.h"
69 
70 /* HMAC pkey context structure */
71 
72 typedef struct {
73 	const EVP_MD *md;	/* MD for HMAC use */
74 	ASN1_OCTET_STRING ktmp; /* Temp storage for key */
75 	HMAC_CTX ctx;
76 } HMAC_PKEY_CTX;
77 
78 static int
pkey_hmac_init(EVP_PKEY_CTX * ctx)79 pkey_hmac_init(EVP_PKEY_CTX *ctx)
80 {
81 	HMAC_PKEY_CTX *hctx;
82 
83 	if ((hctx = calloc(1, sizeof(HMAC_PKEY_CTX))) == NULL)
84 		return 0;
85 
86 	hctx->ktmp.type = V_ASN1_OCTET_STRING;
87 	HMAC_CTX_init(&hctx->ctx);
88 
89 	ctx->data = hctx;
90 	ctx->keygen_info_count = 0;
91 
92 	return 1;
93 }
94 
95 static int
pkey_hmac_copy(EVP_PKEY_CTX * dst,EVP_PKEY_CTX * src)96 pkey_hmac_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
97 {
98 	HMAC_PKEY_CTX *sctx, *dctx;
99 
100 	if (!pkey_hmac_init(dst))
101 		return 0;
102 	sctx = src->data;
103 	dctx = dst->data;
104 	dctx->md = sctx->md;
105 	HMAC_CTX_init(&dctx->ctx);
106 	if (!HMAC_CTX_copy(&dctx->ctx, &sctx->ctx))
107 		return 0;
108 	if (sctx->ktmp.data) {
109 		if (!ASN1_OCTET_STRING_set(&dctx->ktmp, sctx->ktmp.data,
110 		    sctx->ktmp.length))
111 			return 0;
112 	}
113 	return 1;
114 }
115 
116 static void
pkey_hmac_cleanup(EVP_PKEY_CTX * ctx)117 pkey_hmac_cleanup(EVP_PKEY_CTX *ctx)
118 {
119 	HMAC_PKEY_CTX *hctx;
120 
121 	if ((hctx = ctx->data) == NULL)
122 		return;
123 
124 	HMAC_CTX_cleanup(&hctx->ctx);
125 	freezero(hctx->ktmp.data, hctx->ktmp.length);
126 	free(hctx);
127 }
128 
129 static int
pkey_hmac_keygen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)130 pkey_hmac_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
131 {
132 	ASN1_OCTET_STRING *hkey = NULL;
133 	HMAC_PKEY_CTX *hctx = ctx->data;
134 	int ret = 0;
135 
136 	if (hctx->ktmp.data == NULL)
137 		goto err;
138 	if ((hkey = ASN1_OCTET_STRING_dup(&hctx->ktmp)) == NULL)
139 		goto err;
140 	if (!EVP_PKEY_assign(pkey, EVP_PKEY_HMAC, hkey))
141 		goto err;
142 	hkey = NULL;
143 
144 	ret = 1;
145 
146  err:
147 	ASN1_OCTET_STRING_free(hkey);
148 
149 	return ret;
150 }
151 
152 static int
int_update(EVP_MD_CTX * ctx,const void * data,size_t count)153 int_update(EVP_MD_CTX *ctx, const void *data, size_t count)
154 {
155 	HMAC_PKEY_CTX *hctx = ctx->pctx->data;
156 
157 	if (!HMAC_Update(&hctx->ctx, data, count))
158 		return 0;
159 	return 1;
160 }
161 
162 static int
hmac_signctx_init(EVP_PKEY_CTX * ctx,EVP_MD_CTX * mctx)163 hmac_signctx_init(EVP_PKEY_CTX *ctx, EVP_MD_CTX *mctx)
164 {
165 	HMAC_PKEY_CTX *hctx = ctx->data;
166 
167 	HMAC_CTX_set_flags(&hctx->ctx, mctx->flags & ~EVP_MD_CTX_FLAG_NO_INIT);
168 	EVP_MD_CTX_set_flags(mctx, EVP_MD_CTX_FLAG_NO_INIT);
169 	mctx->update = int_update;
170 	return 1;
171 }
172 
173 static int
hmac_signctx(EVP_PKEY_CTX * ctx,unsigned char * sig,size_t * siglen,EVP_MD_CTX * mctx)174 hmac_signctx(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
175     EVP_MD_CTX *mctx)
176 {
177 	unsigned int hlen;
178 	HMAC_PKEY_CTX *hctx = ctx->data;
179 	int l = EVP_MD_CTX_size(mctx);
180 
181 	if (l < 0)
182 		return 0;
183 	*siglen = l;
184 	if (!sig)
185 		return 1;
186 
187 	if (!HMAC_Final(&hctx->ctx, sig, &hlen))
188 		return 0;
189 	*siglen = (size_t)hlen;
190 	return 1;
191 }
192 
193 static int
pkey_hmac_ctrl(EVP_PKEY_CTX * ctx,int type,int p1,void * p2)194 pkey_hmac_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
195 {
196 	HMAC_PKEY_CTX *hctx = ctx->data;
197 	ASN1_OCTET_STRING *key;
198 
199 	switch (type) {
200 	case EVP_PKEY_CTRL_SET_MAC_KEY:
201 		if ((!p2 && p1 > 0) || (p1 < -1))
202 			return 0;
203 		if (!ASN1_OCTET_STRING_set(&hctx->ktmp, p2, p1))
204 			return 0;
205 		break;
206 
207 	case EVP_PKEY_CTRL_MD:
208 		hctx->md = p2;
209 		break;
210 
211 	case EVP_PKEY_CTRL_DIGESTINIT:
212 		key = ctx->pkey->pkey.ptr;
213 		if (!HMAC_Init_ex(&hctx->ctx, key->data, key->length, hctx->md,
214 		    NULL))
215 			return 0;
216 		break;
217 
218 	default:
219 		return -2;
220 	}
221 	return 1;
222 }
223 
224 static int
pkey_hmac_ctrl_str(EVP_PKEY_CTX * ctx,const char * type,const char * value)225 pkey_hmac_ctrl_str(EVP_PKEY_CTX *ctx, const char *type, const char *value)
226 {
227 	if (!value)
228 		return 0;
229 	if (!strcmp(type, "key")) {
230 		void *p = (void *)value;
231 		return pkey_hmac_ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, -1, p);
232 	}
233 	if (!strcmp(type, "hexkey")) {
234 		unsigned char *key;
235 		int r;
236 		long keylen;
237 		key = string_to_hex(value, &keylen);
238 		if (!key)
239 			return 0;
240 		r = pkey_hmac_ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, keylen, key);
241 		free(key);
242 		return r;
243 	}
244 	return -2;
245 }
246 
247 const EVP_PKEY_METHOD hmac_pkey_meth = {
248 	.pkey_id = EVP_PKEY_HMAC,
249 
250 	.init = pkey_hmac_init,
251 	.copy = pkey_hmac_copy,
252 	.cleanup = pkey_hmac_cleanup,
253 
254 	.keygen = pkey_hmac_keygen,
255 
256 	.signctx_init = hmac_signctx_init,
257 	.signctx = hmac_signctx,
258 
259 	.ctrl = pkey_hmac_ctrl,
260 	.ctrl_str = pkey_hmac_ctrl_str
261 };
262