mk_rep.c revision 55682 
1/*
2 * Copyright (c) 1997-1999 Kungliga Tekniska H�gskolan
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
36RCSID("$Id: mk_rep.c,v 1.16 1999/12/02 17:05:11 joda Exp $");
37
38krb5_error_code
39krb5_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	return ENOMEM;
66    *(body.seq_number) = (*auth_context)->local_seqnumber;
67  } else
68    body.seq_number = NULL;
69
70  ap.enc_part.etype = (*auth_context)->keyblock->keytype;
71  ap.enc_part.kvno  = NULL;
72
73  buf_size = length_EncAPRepPart(&body);
74  buf = malloc (buf_size);
75  if (buf == NULL) {
76      free_EncAPRepPart (&body);
77      return ENOMEM;
78  }
79
80  ret = krb5_encode_EncAPRepPart (context,
81				  buf + buf_size - 1,
82				  buf_size,
83				  &body,
84				  &len);
85
86  free_EncAPRepPart (&body);
87  krb5_crypto_init(context, (*auth_context)->keyblock,
88		   0 /* ap.enc_part.etype */, &crypto);
89  ret = krb5_encrypt (context,
90		      crypto,
91		      KRB5_KU_AP_REQ_ENC_PART,
92		      buf + buf_size - len,
93		      len,
94		      &ap.enc_part.cipher);
95  krb5_crypto_destroy(context, crypto);
96  if (ret) {
97      free(buf);
98      return ret;
99  }
100
101  buf_size = length_AP_REP(&ap);
102  buf = realloc(buf, buf_size);
103  if(buf == NULL) {
104      free_AP_REP (&ap);
105      return ENOMEM;
106  }
107  ret = encode_AP_REP (buf + buf_size - 1, buf_size, &ap, &len);
108
109  free_AP_REP (&ap);
110
111  if(len != buf_size)
112      krb5_abortx(context, "krb5_mk_rep: encoded length != calculated length");
113  outbuf->data = buf;
114  outbuf->length = len;
115  return 0;
116}
117