lib/libcrypto/hmac/hm_pmeth.c

   1 /* $OpenBSD: hm_pmeth.c,v 1.10 2017/05/02 03:59:44 deraadt 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_locl.h"
  68
  69 /* HMAC pkey context structure */
  70
  71 typedef struct {
  72         const EVP_MD *md;       /* MD for HMAC use */
  73         ASN1_OCTET_STRING ktmp; /* Temp storage for key */
  74         HMAC_CTX ctx;
  75 } HMAC_PKEY_CTX;
  76
  77 static int
  78 pkey_hmac_init(EVP_PKEY_CTX *ctx)
  79 {
  80         HMAC_PKEY_CTX *hctx;
  81
  82         hctx = malloc(sizeof(HMAC_PKEY_CTX));
  83         if (!hctx)
  84                 return 0;
  85         hctx->md = NULL;
  86         hctx->ktmp.data = NULL;
  87         hctx->ktmp.length = 0;
  88         hctx->ktmp.flags = 0;
  89         hctx->ktmp.type = V_ASN1_OCTET_STRING;
  90         HMAC_CTX_init(&hctx->ctx);
  91
  92         ctx->data = hctx;
  93         ctx->keygen_info_count = 0;
  94
  95         return 1;
  96 }
  97
  98 static int
  99 pkey_hmac_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
 100 {
 101         HMAC_PKEY_CTX *sctx, *dctx;
 102
 103         if (!pkey_hmac_init(dst))
 104                 return 0;
 105         sctx = src->data;
 106         dctx = dst->data;
 107         dctx->md = sctx->md;
 108         HMAC_CTX_init(&dctx->ctx);
 109         if (!HMAC_CTX_copy(&dctx->ctx, &sctx->ctx))
 110                 return 0;
 111         if (sctx->ktmp.data) {
 112                 if (!ASN1_OCTET_STRING_set(&dctx->ktmp, sctx->ktmp.data,
 113                     sctx->ktmp.length))
 114                         return 0;
 115         }
 116         return 1;
 117 }
 118
 119 static void
 120 pkey_hmac_cleanup(EVP_PKEY_CTX *ctx)
 121 {
 122         HMAC_PKEY_CTX *hctx = ctx->data;
 123
 124         HMAC_CTX_cleanup(&hctx->ctx);
 125         freezero(hctx->ktmp.data, hctx->ktmp.length);
 126         free(hctx);
 127 }
 128
 129 static int
 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
 135         if (!hctx->ktmp.data)
 136                 return 0;
 137         hkey = ASN1_OCTET_STRING_dup(&hctx->ktmp);
 138         if (!hkey)
 139                 return 0;
 140         EVP_PKEY_assign(pkey, EVP_PKEY_HMAC, hkey);
 141
 142         return 1;
 143 }
 144
 145 static int
 146 int_update(EVP_MD_CTX *ctx, const void *data, size_t count)
 147 {
 148         HMAC_PKEY_CTX *hctx = ctx->pctx->data;
 149
 150         if (!HMAC_Update(&hctx->ctx, data, count))
 151                 return 0;
 152         return 1;
 153 }
 154
 155 static int
 156 hmac_signctx_init(EVP_PKEY_CTX *ctx, EVP_MD_CTX *mctx)
 157 {
 158         HMAC_PKEY_CTX *hctx = ctx->data;
 159
 160         HMAC_CTX_set_flags(&hctx->ctx, mctx->flags & ~EVP_MD_CTX_FLAG_NO_INIT);
 161         EVP_MD_CTX_set_flags(mctx, EVP_MD_CTX_FLAG_NO_INIT);
 162         mctx->update = int_update;
 163         return 1;
 164 }
 165
 166 static int
 167 hmac_signctx(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
 168     EVP_MD_CTX *mctx)
 169 {
 170         unsigned int hlen;
 171         HMAC_PKEY_CTX *hctx = ctx->data;
 172         int l = EVP_MD_CTX_size(mctx);
 173
 174         if (l < 0)
 175                 return 0;
 176         *siglen = l;
 177         if (!sig)
 178                 return 1;
 179
 180         if (!HMAC_Final(&hctx->ctx, sig, &hlen))
 181                 return 0;
 182         *siglen = (size_t)hlen;
 183         return 1;
 184 }
 185
 186 static int
 187 pkey_hmac_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
 188 {
 189         HMAC_PKEY_CTX *hctx = ctx->data;
 190         ASN1_OCTET_STRING *key;
 191
 192         switch (type) {
 193         case EVP_PKEY_CTRL_SET_MAC_KEY:
 194                 if ((!p2 && p1 > 0) || (p1 < -1))
 195                         return 0;
 196                 if (!ASN1_OCTET_STRING_set(&hctx->ktmp, p2, p1))
 197                         return 0;
 198                 break;
 199
 200         case EVP_PKEY_CTRL_MD:
 201                 hctx->md = p2;
 202                 break;
 203
 204         case EVP_PKEY_CTRL_DIGESTINIT:
 205                 key = (ASN1_OCTET_STRING *)ctx->pkey->pkey.ptr;
 206                 if (!HMAC_Init_ex(&hctx->ctx, key->data, key->length, hctx->md,
 207                     ctx->engine))
 208                         return 0;
 209                 break;
 210
 211         default:
 212                 return -2;
 213         }
 214         return 1;
 215 }
 216
 217 static int
 218 pkey_hmac_ctrl_str(EVP_PKEY_CTX *ctx, const char *type, const char *value)
 219 {
 220         if (!value)
 221                 return 0;
 222         if (!strcmp(type, "key")) {
 223                 void *p = (void *)value;
 224                 return pkey_hmac_ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, -1, p);
 225         }
 226         if (!strcmp(type, "hexkey")) {
 227                 unsigned char *key;
 228                 int r;
 229                 long keylen;
 230                 key = string_to_hex(value, &keylen);
 231                 if (!key)
 232                         return 0;
 233                 r = pkey_hmac_ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, keylen, key);
 234                 free(key);
 235                 return r;
 236         }
 237         return -2;
 238 }
 239
 240 const EVP_PKEY_METHOD hmac_pkey_meth = {
 241         .pkey_id = EVP_PKEY_HMAC,
 242
 243         .init = pkey_hmac_init,
 244         .copy = pkey_hmac_copy,
 245         .cleanup = pkey_hmac_cleanup,
 246
 247         .keygen = pkey_hmac_keygen,
 248
 249         .signctx_init = hmac_signctx_init,
 250         .signctx = hmac_signctx,
 251
 252         .ctrl = pkey_hmac_ctrl,
 253         .ctrl_str = pkey_hmac_ctrl_str
 254 };