1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <syslog.h>
30 #include <pwd.h>
31 #include <unistd.h>
32 #include <strings.h>
33 #include <security/pam_appl.h>
34 #include <security/pam_modules.h>
35 #include <libintl.h>
36 
37 static int parse_allow_name(char *, char *);
38 
39 /*
40  * pam_sm_acct_mgmt	main account managment routine.
41  *			XXX: The routine just prints out a warning message.
42  *			     It may need to force the user to change his/her
43  *			     passwd.
44  */
45 
46 int
47 pam_sm_acct_mgmt(
48 	pam_handle_t *pamh,
49 	int	flags,
50 	int	argc,
51 	const char **argv)
52 {
53 	char	*user;
54 	char	*pg;
55 	int	i;
56 	/*LINTED - set but not used. Would be used in a real module. */
57 	int	debug = 0;
58 	/*LINTED - set but not used. Would be used in a real module. */
59 	int	nowarn = 0;
60 	int	error = 0;
61 
62 	if (argc == 0)
63 		return (PAM_SUCCESS);
64 
65 	if (pam_get_item(pamh, PAM_USER, (void **)&user) != PAM_SUCCESS)
66 		return (PAM_SERVICE_ERR);
67 
68 	if (pam_get_item(pamh, PAM_SERVICE, (void **)&pg) != PAM_SUCCESS)
69 		return (PAM_SERVICE_ERR);
70 
71 	/*
72 	 * kludge alert. su needs to be handled specially for allow policy.
73 	 * we want to use the policy of the current user not the "destination"
74 	 * user. This will enable us to prevent su to root but not to rlogin,
75 	 * telnet, rsh, ftp to root.
76 	 *
77 	 * description of problem: user name is the "destination" name. not
78 	 * the current name. The allow policy needs to be applied to the
79 	 * current name in the case of su. user is "root" in this case and
80 	 * we will be getting the root policy instead of the user policy.
81 	 */
82 	if (strcmp(pg, "su") == 0) {
83 		struct passwd *pw;
84 		uid_t uid;
85 		uid = getuid();
86 		pw = getpwuid(uid);
87 		if (pw == NULL)
88 			return (PAM_SYSTEM_ERR);
89 		user = pw->pw_name;
90 	}
91 
92 	if (user == 0 || *user == '\0' || (strcmp(user, "root") == 0))
93 		return (PAM_SUCCESS);
94 
95 	for (i = 0; i < argc; i++) {
96 		if (strcasecmp(argv[i], "debug") == 0)
97 			debug = 1;
98 		else if (strcasecmp(argv[i], "nowarn") == 0) {
99 			nowarn = 1;
100 			flags = flags | PAM_SILENT;
101 		} else if (strncmp(argv[i], "allow=", 6) == 0)
102 			error |= parse_allow_name(user, (char *)(argv[i]+6));
103 		else
104 			syslog(LOG_DEBUG, "illegal option %s", argv[i]);
105 	}
106 	return (error?PAM_SUCCESS:PAM_AUTH_ERR);
107 }
108 
109 static int
110 parse_allow_name(char *who, char *cp)
111 {
112 	char name[256];
113 	static char *getname();
114 
115 	/* catch "allow=" */
116 	if (*cp == '\0')
117 		return (0);
118 	while (cp) {
119 		cp = getname(cp, name);
120 		/* catch things such as =, and ,, */
121 		if (*name == '\0')
122 			continue;
123 		if (strcmp(who, name) == 0)
124 			return (1);
125 	}
126 	return (0);
127 }
128 
129 static char *
130 getname(char *cp, char *name)
131 {
132 	/* force name to be initially null string */
133 	*name = '\0';
134 
135 	/* end of string? */
136 	if (*cp == '\0')
137 		return ((char *)0);
138 	while (*cp) {
139 		/* end of name? */
140 		if (*cp == ',' || *cp == '\0')
141 			break;
142 		*name++ = *cp++;
143 	}
144 	/* make name into string */
145 	*name++ = '\0';
146 	return ((*cp == '\0')? (char *)0 : ++cp);
147 }
148