1/*
2 * lib/krb5/keytab/read_servi.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 * This routine is designed to be passed to krb5_rd_req.
28 * It is a convenience function that reads a key out of a keytab.
29 * It handles all of the opening and closing of the keytab
30 * internally.
31 */
32
33#include "k5-int.h"
34
35#define KSUCCESS 0
36
37/*
38 * effects: If keyprocarg is not NULL, it is taken to be the name of a
39 *	keytab.  Otherwise, the default keytab will be used.  This
40 *	routine opens the keytab and finds the principal associated with
41 *	principal, vno, and enctype and returns the resulting key in *key
42 *	or returning an error code if it is not	found.
43 * returns: Either KSUCCESS or error code.
44 * errors: error code if not found or keyprocarg is invalid.
45 */
46krb5_error_code KRB5_CALLCONV
47krb5_kt_read_service_key(krb5_context context, krb5_pointer keyprocarg, krb5_principal principal, krb5_kvno vno, krb5_enctype enctype, krb5_keyblock **key)
48{
49    krb5_error_code kerror = KSUCCESS;
50    char keytabname[MAX_KEYTAB_NAME_LEN + 1]; /* + 1 for NULL termination */
51    krb5_keytab id;
52    krb5_keytab_entry entry;
53
54    /*
55     * Get the name of the file that we should use.
56     */
57    if (!keyprocarg) {
58	if ((kerror = krb5_kt_default_name(context, (char *)keytabname,
59					   sizeof(keytabname) - 1))!= KSUCCESS)
60	    return (kerror);
61    } else {
62	memset(keytabname, 0, sizeof(keytabname));
63	(void) strncpy(keytabname, (char *)keyprocarg,
64		       sizeof(keytabname) - 1);
65    }
66
67    if ((kerror = krb5_kt_resolve(context, (char *)keytabname, &id)))
68	return (kerror);
69
70    kerror = krb5_kt_get_entry(context, id, principal, vno, enctype, &entry);
71    /* Solaris Kerberos */
72    (void) krb5_kt_close(context, id);
73
74    if (kerror)
75	return(kerror);
76
77    krb5_copy_keyblock(context, &entry.key, key);
78
79    krb5_kt_free_entry(context, &entry);
80
81    return (KSUCCESS);
82}
83