lib/krb5/rd_priv.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_rd_priv(krb5_context context,
  45              krb5_auth_context auth_context,
  46              const krb5_data *inbuf,
  47              krb5_data *outbuf,
  48              /*krb5_replay_data*/ void *outdata)
  49 {
  50   krb5_error_code ret;
  51   KRB_PRIV priv;
  52   EncKrbPrivPart part;
  53   size_t len;
  54   krb5_data plain;
  55   krb5_keyblock *key;
  56
  57   ret = decode_KRB_PRIV (inbuf->data, inbuf->length, &priv, &len);
  58   if (ret)
  59       goto failure;
  60   if (priv.pvno != 5) {
  61       ret = KRB5KRB_AP_ERR_BADVERSION;
  62       goto failure;
  63   }
  64   if (priv.msg_type != krb_priv) {
  65       ret = KRB5KRB_AP_ERR_MSG_TYPE;
  66       goto failure;
  67   }
  68
  69   /* XXX - Is this right? */
  70
  71   if (auth_context->local_subkey.keytype)
  72       key = &auth_context->local_subkey;
  73   else if (auth_context->remote_subkey.keytype)
  74       key = &auth_context->remote_subkey;
  75   else
  76       key = auth_context->keyblock;
  77
  78   ret = krb5_decrypt (context,
  79                       priv.enc_part.cipher.data,
  80                       priv.enc_part.cipher.length,
  81                       priv.enc_part.etype,
  82                       key,
  83                       &plain);
  84   if (ret)
  85       goto failure;
  86
  87   ret = decode_EncKrbPrivPart (plain.data, plain.length, &part, &len);
  88   krb5_data_free (&plain);
  89   if (ret)
  90       goto failure;
  91
  92   /* check sender address */
  93
  94   if (part.s_address
  95       && auth_context->remote_address
  96       && !krb5_address_compare (context,
  97                                 auth_context->remote_address,
  98                                 part.s_address)) {
  99       ret = KRB5KRB_AP_ERR_BADADDR;
 100       goto failure_part;
 101   }
 102
 103   /* check receiver address */
 104
 105   if (part.r_address
 106       && auth_context->local_address
 107       && !krb5_address_compare (context,
 108                                 auth_context->local_address,
 109                                 part.r_address)) {
 110       ret = KRB5KRB_AP_ERR_BADADDR;
 111       goto failure_part;
 112   }
 113
 114   /* check timestamp */
 115   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
 116       int32_t sec;
 117
 118       krb5_timeofday (context, &sec);
 119     if (part.timestamp == NULL ||
 120         part.usec      == NULL ||
 121         abs(*part.timestamp - sec) > context->max_skew) {
 122         ret = KRB5KRB_AP_ERR_SKEW;
 123         goto failure_part;
 124     }
 125   }
 126
 127   /* XXX - check replay cache */
 128
 129   /* check sequence number */
 130   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
 131     if (part.seq_number == NULL ||
 132         *part.seq_number != ++auth_context->remote_seqnumber) {
 133       ret = KRB5KRB_AP_ERR_BADORDER;
 134       goto failure_part;
 135     }
 136   }
 137
 138   ret = krb5_data_copy (outbuf, part.user_data.data, part.user_data.length);
 139   if (ret)
 140       goto failure_part;
 141
 142   free_EncKrbPrivPart (&part);
 143   free_KRB_PRIV (&priv);
 144   return 0;
 145
 146 failure_part:
 147   free_EncKrbPrivPart (&part);
 148
 149 failure:
 150   free_KRB_PRIV (&priv);
 151   return ret;
 152 }