lib/krb5/rd_rep.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 RCSID("$Id$");
  37
  38 krb5_error_code KRB5_LIB_FUNCTION
  39 krb5_rd_rep(krb5_context context,
  40             krb5_auth_context auth_context,
  41             const krb5_data *inbuf,
  42             krb5_ap_rep_enc_part **repl)
  43 {
  44     krb5_error_code ret;
  45     AP_REP ap_rep;
  46     size_t len;
  47     krb5_data data;
  48     krb5_crypto crypto;
  49
  50     krb5_data_zero (&data);
  51     ret = 0;
  52
  53     ret = decode_AP_REP(inbuf->data, inbuf->length, &ap_rep, &len);
  54     if (ret)
  55         return ret;
  56     if (ap_rep.pvno != 5) {
  57         ret = KRB5KRB_AP_ERR_BADVERSION;
  58         krb5_clear_error_string (context);
  59         goto out;
  60     }
  61     if (ap_rep.msg_type != krb_ap_rep) {
  62         ret = KRB5KRB_AP_ERR_MSG_TYPE;
  63         krb5_clear_error_string (context);
  64         goto out;
  65     }
  66
  67     ret = krb5_crypto_init(context, auth_context->keyblock, 0, &crypto);
  68     if (ret)
  69         goto out;
  70     ret = krb5_decrypt_EncryptedData (context,
  71                                       crypto,
  72                                       KRB5_KU_AP_REQ_ENC_PART,
  73                                       &ap_rep.enc_part,
  74                                       &data);
  75     krb5_crypto_destroy(context, crypto);
  76     if (ret)
  77         goto out;
  78
  79     *repl = malloc(sizeof(**repl));
  80     if (*repl == NULL) {
  81         ret = ENOMEM;
  82         krb5_set_error_string (context, "malloc: out of memory");
  83         goto out;
  84     }
  85     ret = krb5_decode_EncAPRepPart(context,
  86                                    data.data,
  87                                    data.length,
  88                                    *repl,
  89                                    &len);
  90     if (ret)
  91         return ret;
  92
  93     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
  94         if ((*repl)->ctime != auth_context->authenticator->ctime ||
  95             (*repl)->cusec != auth_context->authenticator->cusec)
  96         {
  97             krb5_free_ap_rep_enc_part(context, *repl);
  98             *repl = NULL;
  99             ret = KRB5KRB_AP_ERR_MUT_FAIL;
 100             krb5_clear_error_string (context);
 101             goto out;
 102         }
 103     }
 104     if ((*repl)->seq_number)
 105         krb5_auth_con_setremoteseqnumber(context, auth_context,
 106                                          *((*repl)->seq_number));
 107     if ((*repl)->subkey)
 108         krb5_auth_con_setremotesubkey(context, auth_context, (*repl)->subkey);
 109
 110  out:
 111     krb5_data_free (&data);
 112     free_AP_REP (&ap_rep);
 113     return ret;
 114 }
 115
 116 void KRB5_LIB_FUNCTION
 117 krb5_free_ap_rep_enc_part (krb5_context context,
 118                            krb5_ap_rep_enc_part *val)
 119 {
 120     if (val) {
 121         free_EncAPRepPart (val);
 122         free (val);
 123     }
 124 }