xref: /freebsd/crypto/heimdal/lib/krb5/kuserok.c (revision 4b2eaea43fec8e8792be611dea204071a10b655a)
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 
36 RCSID("$Id: kuserok.c,v 1.5.12.1 2002/10/21 14:37:55 joda Exp $");
37 
38 /*
39  * Return TRUE iff `principal' is allowed to login as `luser'.
40  */
41 
42 krb5_boolean
43 krb5_kuserok (krb5_context context,
44 	      krb5_principal principal,
45 	      const char *luser)
46 {
47     char buf[BUFSIZ];
48     struct passwd *pwd;
49     FILE *f;
50     krb5_realm *realms, *r;
51     krb5_error_code ret;
52     krb5_boolean b;
53 
54     ret = krb5_get_default_realms (context, &realms);
55     if (ret)
56 	return FALSE;
57 
58     for (r = realms; *r != NULL; ++r) {
59 	krb5_principal local_principal;
60 
61 	ret = krb5_build_principal (context,
62 				    &local_principal,
63 				    strlen(*r),
64 				    *r,
65 				    luser,
66 				    NULL);
67 	if (ret) {
68 	    krb5_free_host_realm (context, realms);
69 	    return FALSE;
70 	}
71 
72 	b = krb5_principal_compare (context, principal, local_principal);
73 	krb5_free_principal (context, local_principal);
74 	if (b) {
75 	    krb5_free_host_realm (context, realms);
76 	    return TRUE;
77 	}
78     }
79     krb5_free_host_realm (context, realms);
80 
81     pwd = getpwnam (luser);	/* XXX - Should use k_getpwnam? */
82     if (pwd == NULL)
83 	return FALSE;
84     snprintf (buf, sizeof(buf), "%s/.k5login", pwd->pw_dir);
85     f = fopen (buf, "r");
86     if (f == NULL)
87 	return FALSE;
88     while (fgets (buf, sizeof(buf), f) != NULL) {
89 	krb5_principal tmp;
90 
91 	buf[strcspn(buf, "\n")] = '\0';
92 	ret = krb5_parse_name (context, buf, &tmp);
93 	if (ret) {
94 	    fclose (f);
95 	    return FALSE;
96 	}
97 	b = krb5_principal_compare (context, principal, tmp);
98 	krb5_free_principal (context, tmp);
99 	if (b) {
100 	    fclose (f);
101 	    return TRUE;
102 	}
103     }
104     fclose (f);
105     return FALSE;
106 }
107