freebsd-dev/crypto/heimdal/lib/krb5/generate_seq_number.c
2001-06-21 02:12:07 +00:00

63 lines
2.2 KiB
C

/*
* Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <krb5_locl.h>
RCSID("$Id: generate_seq_number.c,v 1.8 2001/05/08 14:05:37 assar Exp $");
krb5_error_code
krb5_generate_seq_number(krb5_context context,
const krb5_keyblock *key,
u_int32_t *seqno)
{
krb5_error_code ret;
krb5_keyblock *subkey;
u_int32_t q;
u_char *p;
int i;
ret = krb5_generate_subkey (context, key, &subkey);
if (ret)
return ret;
q = 0;
for (p = (u_char *)subkey->keyvalue.data, i = 0;
i < subkey->keyvalue.length;
++i, ++p)
q = (q << 8) | *p;
q &= 0xffffffff;
*seqno = q;
krb5_free_keyblock (context, subkey);
return 0;
}