1#pragma ident	"%Z%%M%	%I%	%E% SMI"
2/*
3 * lib/krb5/krb/decrypt_tk.c
4 *
5 * Copyright 1990 by the Massachusetts Institute of Technology.
6 * All Rights Reserved.
7 *
8 * Export of this software from the United States of America may
9 *   require a specific license from the United States Government.
10 *   It is the responsibility of any person or organization contemplating
11 *   export to obtain such a license before exporting.
12 *
13 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
14 * distribute this software and its documentation for any purpose and
15 * without fee is hereby granted, provided that the above copyright
16 * notice appear in all copies and that both that copyright notice and
17 * this permission notice appear in supporting documentation, and that
18 * the name of M.I.T. not be used in advertising or publicity pertaining
19 * to distribution of the software without specific, written prior
20 * permission.  Furthermore if you modify this software you must label
21 * your software as modified software and not distribute it in such a
22 * fashion that it might be confused with the original M.I.T. software.
23 * M.I.T. makes no representations about the suitability of
24 * this software for any purpose.  It is provided "as is" without express
25 * or implied warranty.
26 *
27 *
28 * krb5_decrypt_tkt_part() function.
29 */
30
31#include <k5-int.h>
32
33/*
34 Decrypts dec_ticket->enc_part
35 using *srv_key, and places result in dec_ticket->enc_part2.
36 The storage of dec_ticket->enc_part2 will be allocated before return.
37
38 returns errors from encryption routines, system errors
39
40*/
41
42/*ARGSUSED*/
43krb5_error_code KRB5_CALLCONV
44krb5_decrypt_tkt_part(krb5_context context, const krb5_keyblock *srv_key, register krb5_ticket *ticket)
45{
46    krb5_enc_tkt_part *dec_tkt_part;
47    krb5_data scratch;
48    krb5_error_code retval;
49
50    if (!krb5_c_valid_enctype(ticket->enc_part.enctype))
51	return KRB5_PROG_ETYPE_NOSUPP;
52
53    scratch.length = ticket->enc_part.ciphertext.length;
54    if (!(scratch.data = malloc(ticket->enc_part.ciphertext.length)))
55	return(ENOMEM);
56
57    /* call the encryption routine */
58    if ((retval = krb5_c_decrypt(context, srv_key,
59				KRB5_KEYUSAGE_KDC_REP_TICKET, 0,
60				&ticket->enc_part, &scratch))) {
61	free(scratch.data);
62	return retval;
63    }
64
65#define clean_scratch() {memset(scratch.data, 0, scratch.length); \
66free(scratch.data);}
67
68    /*  now decode the decrypted stuff */
69    retval = decode_krb5_enc_tkt_part(&scratch, &dec_tkt_part);
70    if (!retval) {
71	ticket->enc_part2 = dec_tkt_part;
72    }
73    clean_scratch();
74    return retval;
75}
76