lib/krb5/mk_rep.c

   1 /*
   2  * Copyright (c) 1997 - 2002 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 RCSID("$Id$");
  37
  38 krb5_error_code
  39 krb5_mk_rep(krb5_context context,
  40             krb5_auth_context auth_context,
  41             krb5_data *outbuf)
  42 {
  43   krb5_error_code ret;
  44   AP_REP ap;
  45   EncAPRepPart body;
  46   u_char *buf = NULL;
  47   size_t buf_size;
  48   size_t len;
  49   krb5_crypto crypto;
  50
  51   ap.pvno = 5;
  52   ap.msg_type = krb_ap_rep;
  53
  54   memset (&body, 0, sizeof(body));
  55
  56   body.ctime = auth_context->authenticator->ctime;
  57   body.cusec = auth_context->authenticator->cusec;
  58   body.subkey = NULL;
  59   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
  60     krb5_generate_seq_number (context,
  61                               auth_context->keyblock,
  62                               &auth_context->local_seqnumber);
  63     body.seq_number = malloc (sizeof(*body.seq_number));
  64     if (body.seq_number == NULL) {
  65         krb5_set_error_string (context, "malloc: out of memory");
  66         return ENOMEM;
  67     }
  68     *(body.seq_number) = auth_context->local_seqnumber;
  69   } else
  70     body.seq_number = NULL;
  71
  72   ap.enc_part.etype = auth_context->keyblock->keytype;
  73   ap.enc_part.kvno  = NULL;
  74
  75   ASN1_MALLOC_ENCODE(EncAPRepPart, buf, buf_size, &body, &len, ret);
  76   free_EncAPRepPart (&body);
  77   if(ret)
  78       return ret;
  79   ret = krb5_crypto_init(context, auth_context->keyblock,
  80                          0 /* ap.enc_part.etype */, &crypto);
  81   if (ret) {
  82       free (buf);
  83       return ret;
  84   }
  85   ret = krb5_encrypt (context,
  86                       crypto,
  87                       KRB5_KU_AP_REQ_ENC_PART,
  88                       buf + buf_size - len,
  89                       len,
  90                       &ap.enc_part.cipher);
  91   krb5_crypto_destroy(context, crypto);
  92   if (ret) {
  93       free(buf);
  94       return ret;
  95   }
  96
  97   ASN1_MALLOC_ENCODE(AP_REP, outbuf->data, outbuf->length, &ap, &len, ret);
  98   free_AP_REP (&ap);
  99   return ret;
 100 }