lib/krb5/keyblock.c

   1 /*
   2  * Copyright (c) 1997 - 2001 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  * Zero out a keyblock
  38  *
  39  * @param keyblock keyblock to zero out
  40  *
  41  * @ingroup krb5_crypto
  42  */
  43
  44 void KRB5_LIB_FUNCTION
  45 krb5_keyblock_zero(krb5_keyblock *keyblock)
  46 {
  47     keyblock->keytype = 0;
  48     krb5_data_zero(&keyblock->keyvalue);
  49 }
  50
  51 /**
  52  * Free a keyblock's content, also zero out the content of the keyblock.
  53  *
  54  * @param context a Kerberos 5 context
  55  * @param keyblock keyblock content to free, NULL is valid argument
  56  *
  57  * @ingroup krb5_crypto
  58  */
  59
  60 void KRB5_LIB_FUNCTION
  61 krb5_free_keyblock_contents(krb5_context context,
  62                             krb5_keyblock *keyblock)
  63 {
  64     if(keyblock) {
  65         if (keyblock->keyvalue.data != NULL)
  66             memset(keyblock->keyvalue.data, 0, keyblock->keyvalue.length);
  67         krb5_data_free (&keyblock->keyvalue);
  68         keyblock->keytype = ENCTYPE_NULL;
  69     }
  70 }
  71
  72 /**
  73  * Free a keyblock, also zero out the content of the keyblock, uses
  74  * krb5_free_keyblock_contents() to free the content.
  75  *
  76  * @param context a Kerberos 5 context
  77  * @param keyblock keyblock to free, NULL is valid argument
  78  *
  79  * @ingroup krb5_crypto
  80  */
  81
  82 void KRB5_LIB_FUNCTION
  83 krb5_free_keyblock(krb5_context context,
  84                    krb5_keyblock *keyblock)
  85 {
  86     if(keyblock){
  87         krb5_free_keyblock_contents(context, keyblock);
  88         free(keyblock);
  89     }
  90 }
  91
  92 /**
  93  * Copy a keyblock, free the output keyblock with
  94  * krb5_free_keyblock_contents().
  95  *
  96  * @param context a Kerberos 5 context
  97  * @param inblock the key to copy
  98  * @param to the output key.
  99  *
 100  * @return 0 on success or a Kerberos 5 error code
 101  *
 102  * @ingroup krb5_crypto
 103  */
 104
 105 krb5_error_code KRB5_LIB_FUNCTION
 106 krb5_copy_keyblock_contents (krb5_context context,
 107                              const krb5_keyblock *inblock,
 108                              krb5_keyblock *to)
 109 {
 110     return copy_EncryptionKey(inblock, to);
 111 }
 112
 113 /**
 114  * Copy a keyblock, free the output keyblock with
 115  * krb5_free_keyblock().
 116  *
 117  * @param context a Kerberos 5 context
 118  * @param inblock the key to copy
 119  * @param to the output key.
 120  *
 121  * @return 0 on success or a Kerberos 5 error code
 122  *
 123  * @ingroup krb5_crypto
 124  */
 125
 126
 127 krb5_error_code KRB5_LIB_FUNCTION
 128 krb5_copy_keyblock (krb5_context context,
 129                     const krb5_keyblock *inblock,
 130                     krb5_keyblock **to)
 131 {
 132     krb5_error_code ret;
 133     krb5_keyblock *k;
 134
 135     *to = NULL;
 136
 137     k = calloc (1, sizeof(*k));
 138     if (k == NULL) {
 139         krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
 140         return ENOMEM;
 141     }
 142
 143     ret = krb5_copy_keyblock_contents (context, inblock, k);
 144     if (ret) {
 145       free(k);
 146       return ret;
 147     }
 148     *to = k;
 149     return 0;
 150 }
 151
 152 /**
 153  * Get encryption type of a keyblock.
 154  *
 155  * @ingroup krb5_crypto
 156  */
 157
 158 krb5_enctype
 159 krb5_keyblock_get_enctype(const krb5_keyblock *block)
 160 {
 161     return block->keytype;
 162 }
 163
 164 /**
 165  * Fill in `key' with key data of type `enctype' from `data' of length
 166  * `size'. Key should be freed using krb5_free_keyblock_contents().
 167  *
 168  * @return 0 on success or a Kerberos 5 error code
 169  *
 170  * @ingroup krb5_crypto
 171  */
 172
 173 krb5_error_code KRB5_LIB_FUNCTION
 174 krb5_keyblock_init(krb5_context context,
 175                    krb5_enctype type,
 176                    const void *data,
 177                    size_t size,
 178                    krb5_keyblock *key)
 179 {
 180     krb5_error_code ret;
 181     size_t len;
 182
 183     memset(key, 0, sizeof(*key));
 184
 185     ret = krb5_enctype_keysize(context, type, &len);
 186     if (ret)
 187         return ret;
 188
 189     if (len != size) {
 190         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
 191                                "Encryption key %d is %lu bytes "
 192                                "long, %lu was passed in",
 193                                type, (unsigned long)len, (unsigned long)size);
 194         return KRB5_PROG_ETYPE_NOSUPP;
 195     }
 196     ret = krb5_data_copy(&key->keyvalue, data, len);
 197     if(ret) {
 198         krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
 199         return ret;
 200     }
 201     key->keytype = type;
 202
 203     return 0;
 204 }