lib/krb5/crypto-aes-sha2.c

   1 /*
   2  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "krb5_locl.h"
  35
  36 /*
  37  * AES HMAC-SHA2
  38  */
  39
  40 krb5_error_code
  41 _krb5_aes_sha2_md_for_enctype(krb5_context context,
  42                               krb5_enctype enctype,
  43                               const EVP_MD **md)
  44 {
  45     switch (enctype) {
  46     case ETYPE_AES128_CTS_HMAC_SHA256_128:
  47         *md = EVP_sha256();
  48         break;
  49     case ETYPE_AES256_CTS_HMAC_SHA384_192:
  50         *md = EVP_sha384();
  51         break;
  52     default:
  53         return KRB5_PROG_ETYPE_NOSUPP;
  54         break;
  55     }
  56     return 0;
  57 }
  58
  59 static krb5_error_code
  60 SP_HMAC_SHA2_checksum(krb5_context context,
  61                       struct _krb5_key_data *key,
  62                       const void *data,
  63                       size_t len,
  64                       unsigned usage,
  65                       Checksum *result)
  66 {
  67     krb5_error_code ret;
  68     const EVP_MD *md;
  69     unsigned char hmac[EVP_MAX_MD_SIZE];
  70     unsigned int hmaclen = sizeof(hmac);
  71
  72     ret = _krb5_aes_sha2_md_for_enctype(context, key->key->keytype, &md);
  73     if (ret)
  74         return ret;
  75
  76     HMAC(md, key->key->keyvalue.data, key->key->keyvalue.length,
  77          data, len, hmac, &hmaclen);
  78
  79     heim_assert(result->checksum.length <= hmaclen, "SHA2 internal error");
  80
  81     memcpy(result->checksum.data, hmac, result->checksum.length);
  82
  83     return 0;
  84 }
  85
  86 static struct _krb5_key_type keytype_aes128_sha2 = {
  87     KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
  88     "aes-128-sha2",
  89     128,
  90     16,
  91     sizeof(struct _krb5_evp_schedule),
  92     NULL,
  93     _krb5_evp_schedule,
  94     _krb5_AES_SHA2_salt,
  95     NULL,
  96     _krb5_evp_cleanup,
  97     EVP_aes_128_cbc
  98 };
  99
 100 static struct _krb5_key_type keytype_aes256_sha2 = {
 101     KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
 102     "aes-256-sha2",
 103     256,
 104     32,
 105     sizeof(struct _krb5_evp_schedule),
 106     NULL,
 107     _krb5_evp_schedule,
 108     _krb5_AES_SHA2_salt,
 109     NULL,
 110     _krb5_evp_cleanup,
 111     EVP_aes_256_cbc
 112 };
 113
 114 struct _krb5_checksum_type _krb5_checksum_hmac_sha256_128_aes128 = {
 115     CKSUMTYPE_HMAC_SHA256_128_AES128,
 116     "hmac-sha256-128-aes128",
 117     64,
 118     16,
 119     F_KEYED | F_CPROOF | F_DERIVED,
 120     SP_HMAC_SHA2_checksum,
 121     NULL
 122 };
 123
 124 struct _krb5_checksum_type _krb5_checksum_hmac_sha384_192_aes256 = {
 125     CKSUMTYPE_HMAC_SHA384_192_AES256,
 126     "hmac-sha384-192-aes256",
 127     128,
 128     24,
 129     F_KEYED | F_CPROOF | F_DERIVED,
 130     SP_HMAC_SHA2_checksum,
 131     NULL
 132 };
 133
 134 static krb5_error_code
 135 AES_SHA2_PRF(krb5_context context,
 136              krb5_crypto crypto,
 137              const krb5_data *in,
 138              krb5_data *out)
 139 {
 140     krb5_error_code ret;
 141     krb5_data label;
 142     const EVP_MD *md = NULL;
 143
 144     ret = _krb5_aes_sha2_md_for_enctype(context, crypto->et->type, &md);
 145     if (ret)
 146         return ret;
 147
 148     label.data = "prf";
 149     label.length = 3;
 150
 151     ret = krb5_data_alloc(out, EVP_MD_size(md));
 152     if (ret)
 153         return ret;
 154
 155     ret = _krb5_SP800_108_HMAC_KDF(context, &crypto->key.key->keyvalue,
 156                                    &label, in, md, out);
 157
 158     if (ret)
 159         krb5_data_free(out);
 160
 161     return ret;
 162 }
 163
 164 struct _krb5_encryption_type _krb5_enctype_aes128_cts_hmac_sha256_128 = {
 165     ETYPE_AES128_CTS_HMAC_SHA256_128,
 166     "aes128-cts-hmac-sha256-128",
 167     "aes128-cts-sha256",
 168     16,
 169     1,
 170     16,
 171     &keytype_aes128_sha2,
 172     NULL, /* should never be called */
 173     &_krb5_checksum_hmac_sha256_128_aes128,
 174     F_DERIVED | F_ENC_THEN_CKSUM | F_SP800_108_HMAC_KDF,
 175     _krb5_evp_encrypt_cts,
 176     16,
 177     AES_SHA2_PRF
 178 };
 179
 180 struct _krb5_encryption_type _krb5_enctype_aes256_cts_hmac_sha384_192 = {
 181     ETYPE_AES256_CTS_HMAC_SHA384_192,
 182     "aes256-cts-hmac-sha384-192",
 183     "aes256-cts-sha384",
 184     16,
 185     1,
 186     16,
 187     &keytype_aes256_sha2,
 188     NULL, /* should never be called */
 189     &_krb5_checksum_hmac_sha384_192_aes256,
 190     F_DERIVED | F_ENC_THEN_CKSUM | F_SP800_108_HMAC_KDF,
 191     _krb5_evp_encrypt_cts,
 192     16,
 193     AES_SHA2_PRF
 194 };