crypto/hmac/hm_ameth.c

   1 /*
   2  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   3  * 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 "internal/cryptlib.h"
  61 #include <openssl/evp.h>
  62 #include "internal/asn1_int.h"
  63
  64 #define HMAC_TEST_PRIVATE_KEY_FORMAT
  65
  66 /*
  67  * HMAC "ASN1" method. This is just here to indicate the maximum HMAC output
  68  * length and to free up an HMAC key.
  69  */
  70
  71 static int hmac_size(const EVP_PKEY *pkey)
  72 {
  73     return EVP_MAX_MD_SIZE;
  74 }
  75
  76 static void hmac_key_free(EVP_PKEY *pkey)
  77 {
  78     ASN1_OCTET_STRING *os = EVP_PKEY_get0(pkey);
  79     if (os) {
  80         if (os->data)
  81             OPENSSL_cleanse(os->data, os->length);
  82         ASN1_OCTET_STRING_free(os);
  83     }
  84 }
  85
  86 static int hmac_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
  87 {
  88     switch (op) {
  89     case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
  90         *(int *)arg2 = NID_sha256;
  91         return 1;
  92
  93     default:
  94         return -2;
  95     }
  96 }
  97
  98 #ifdef HMAC_TEST_PRIVATE_KEY_FORMAT
  99 /*
 100  * A bogus private key format for test purposes. This is simply the HMAC key
 101  * with "HMAC PRIVATE KEY" in the headers. When enabled the genpkey utility
 102  * can be used to "generate" HMAC keys.
 103  */
 104
 105 static int old_hmac_decode(EVP_PKEY *pkey,
 106                            const unsigned char **pder, int derlen)
 107 {
 108     ASN1_OCTET_STRING *os;
 109     os = ASN1_OCTET_STRING_new();
 110     if (os == NULL || !ASN1_OCTET_STRING_set(os, *pder, derlen))
 111         goto err;
 112     if (!EVP_PKEY_assign(pkey, EVP_PKEY_HMAC, os))
 113         goto err;
 114     return 1;
 115
 116  err:
 117     ASN1_OCTET_STRING_free(os);
 118     return 0;
 119 }
 120
 121 static int old_hmac_encode(const EVP_PKEY *pkey, unsigned char **pder)
 122 {
 123     int inc;
 124     ASN1_OCTET_STRING *os = EVP_PKEY_get0(pkey);
 125     if (pder) {
 126         if (!*pder) {
 127             *pder = OPENSSL_malloc(os->length);
 128             if (*pder == NULL)
 129                 return -1;
 130             inc = 0;
 131         } else
 132             inc = 1;
 133
 134         memcpy(*pder, os->data, os->length);
 135
 136         if (inc)
 137             *pder += os->length;
 138     }
 139
 140     return os->length;
 141 }
 142
 143 #endif
 144
 145 const EVP_PKEY_ASN1_METHOD hmac_asn1_meth = {
 146     EVP_PKEY_HMAC,
 147     EVP_PKEY_HMAC,
 148     0,
 149
 150     "HMAC",
 151     "OpenSSL HMAC method",
 152
 153     0, 0, 0, 0,
 154
 155     0, 0, 0,
 156
 157     hmac_size,
 158     0, 0,
 159     0, 0, 0, 0, 0, 0, 0,
 160
 161     hmac_key_free,
 162     hmac_pkey_ctrl,
 163 #ifdef HMAC_TEST_PRIVATE_KEY_FORMAT
 164     old_hmac_decode,
 165     old_hmac_encode
 166 #else
 167     0, 0
 168 #endif
 169 };