lib/krb5/mk_safe.c

   1 /*
   2  * Copyright (c) 1997 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. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed by Kungliga Tekniska
  20  *      Högskolan and its contributors.
  21  *
  22  * 4. Neither the name of the Institute nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  */
  38
  39 #include <krb5_locl.h>
  40
  41 RCSID("$Id$");
  42
  43 krb5_error_code
  44 krb5_mk_safe(krb5_context context,
  45              krb5_auth_context auth_context,
  46              const krb5_data *userdata,
  47              krb5_data *outbuf,
  48              /*krb5_replay_data*/ void *outdata)
  49 {
  50   krb5_error_code r;
  51   KRB_SAFE s;
  52   int32_t sec, usec;
  53   KerberosTime sec2;
  54   unsigned usec2;
  55   u_char buf[1024];
  56   size_t len;
  57   unsigned tmp_seq;
  58   krb5_cksumtype cksumtype;
  59
  60   if (auth_context->cksumtype)
  61       cksumtype = auth_context->cksumtype;
  62   else {
  63       r = krb5_keytype_to_cksumtype (context,
  64                                      auth_context->keyblock->keytype,
  65                                      &cksumtype);
  66       if (r)
  67           return r;
  68   }
  69
  70   s.pvno = 5;
  71   s.msg_type = krb_safe;
  72
  73   s.safe_body.user_data = *userdata;
  74   krb5_us_timeofday (context, &sec, &usec);
  75
  76   sec2 = sec;
  77   s.safe_body.timestamp  = &sec2;
  78   usec2 = usec2;
  79   s.safe_body.usec       = &usec2;
  80   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
  81       tmp_seq = ++auth_context->local_seqnumber;
  82       s.safe_body.seq_number = &tmp_seq;
  83   } else
  84       s.safe_body.seq_number = NULL;
  85
  86   s.safe_body.s_address = auth_context->local_address;
  87   s.safe_body.r_address = auth_context->remote_address;
  88
  89   s.cksum.cksumtype       = 0;
  90   s.cksum.checksum.data   = NULL;
  91   s.cksum.checksum.length = 0;
  92
  93   r = encode_KRB_SAFE (buf + sizeof(buf) - 1,
  94                        sizeof(buf),
  95                        &s,
  96                        &len);
  97
  98   if (r)
  99     return r;
 100
 101   r = krb5_create_checksum (context,
 102                             cksumtype,
 103                             buf + sizeof(buf) - len,
 104                             len,
 105                             auth_context->keyblock,
 106                             &s.cksum);
 107   if (r)
 108     return r;
 109
 110   r = encode_KRB_SAFE (buf + sizeof(buf) - 1, sizeof(buf), &s, &len);
 111   if (r)
 112     return r;
 113
 114   outbuf->length = len;
 115   outbuf->data   = malloc (len);
 116   if (outbuf->data == NULL)
 117     return ENOMEM;
 118   memcpy (outbuf->data, buf + sizeof(buf) - len, len);
 119   return 0;
 120 }