1/*
2 * lib/krb5/krb/decode_kdc.c
3 *
4 * Copyright 1990 by the Massachusetts Institute of Technology.
5 * All Rights Reserved.
6 *
7 * Export of this software from the United States of America may
8 *   require a specific license from the United States Government.
9 *   It is the responsibility of any person or organization contemplating
10 *   export to obtain such a license before exporting.
11 *
12 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
13 * distribute this software and its documentation for any purpose and
14 * without fee is hereby granted, provided that the above copyright
15 * notice appear in all copies and that both that copyright notice and
16 * this permission notice appear in supporting documentation, and that
17 * the name of M.I.T. not be used in advertising or publicity pertaining
18 * to distribution of the software without specific, written prior
19 * permission.  Furthermore if you modify this software you must label
20 * your software as modified software and not distribute it in such a
21 * fashion that it might be confused with the original M.I.T. software.
22 * M.I.T. makes no representations about the suitability of
23 * this software for any purpose.  It is provided "as is" without express
24 * or implied warranty.
25 *
26 *
27 * krb5_decode_kdc_rep() function.
28 */
29
30#include "k5-int.h"
31
32/*
33 Takes a KDC_REP message and decrypts encrypted part using etype and
34 *key, putting result in *rep.
35 dec_rep->client,ticket,session,last_req,server,caddrs
36 are all set to allocated storage which should be freed by the caller
37 when finished with the response.
38
39 If the response isn't a KDC_REP (tgs or as), it returns an error from
40 the decoding routines.
41
42 returns errors from encryption routines, system errors
43 */
44
45krb5_error_code
46krb5_decode_kdc_rep(krb5_context context, krb5_data *enc_rep, const krb5_keyblock *key, krb5_kdc_rep **dec_rep)
47{
48    krb5_error_code retval;
49    krb5_kdc_rep *local_dec_rep;
50    krb5_keyusage usage;
51
52    if (krb5_is_as_rep(enc_rep)) {
53	usage = KRB5_KEYUSAGE_AS_REP_ENCPART;
54	retval = decode_krb5_as_rep(enc_rep, &local_dec_rep);
55    } else if (krb5_is_tgs_rep(enc_rep)) {
56	usage = KRB5_KEYUSAGE_TGS_REP_ENCPART_SESSKEY;
57	/* KRB5_KEYUSAGE_TGS_REP_ENCPART_SUBKEY would go here, except
58	   that this client code base doesn't ever put a subkey in the
59	   tgs_req authenticator, so the tgs_rep is never encrypted in
60	   one.  (Check send_tgs.c:krb5_send_tgs_basic(), near the top
61	   where authent.subkey is set to 0) */
62	retval = decode_krb5_tgs_rep(enc_rep, &local_dec_rep);
63    } else {
64	return KRB5KRB_AP_ERR_MSG_TYPE;
65    }
66
67    if (retval)
68	return retval;
69
70    if ((retval = krb5_kdc_rep_decrypt_proc(context, key, &usage,
71					    local_dec_rep)))
72	krb5_free_kdc_rep(context, local_dec_rep);
73    else
74    	*dec_rep = local_dec_rep;
75    return(retval);
76}
77
78