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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <syslog.h>
27 #include <pwd.h>
28 #include <unistd.h>
29 #include <strings.h>
30 #include <security/pam_appl.h>
31 #include <security/pam_modules.h>
32 #include <libintl.h>
33 
34 static int parse_allow_name(char *, char *);
35 
36 /*
37  * pam_sm_acct_mgmt	main account managment routine.
38  *			XXX: The routine just prints out a warning message.
39  *			     It may need to force the user to change his/her
40  *			     passwd.
41  */
42 
43 int
44 pam_sm_acct_mgmt(
45 	pam_handle_t *pamh,
46 	int	flags,
47 	int	argc,
48 	const char **argv)
49 {
50 	char	*user;
51 	char	*pg;
52 	int	i;
53 	/*LINTED - set but not used. Would be used in a real module. */
54 	int	debug = 0;
55 	/*LINTED - set but not used. Would be used in a real module. */
56 	int	nowarn = 0;
57 	int	error = 0;
58 
59 	if (argc == 0)
60 		return (PAM_SUCCESS);
61 
62 	if (pam_get_item(pamh, PAM_USER, (void **)&user) != PAM_SUCCESS)
63 		return (PAM_SERVICE_ERR);
64 
65 	if (pam_get_item(pamh, PAM_SERVICE, (void **)&pg) != PAM_SUCCESS)
66 		return (PAM_SERVICE_ERR);
67 
68 	/*
69 	 * kludge alert. su needs to be handled specially for allow policy.
70 	 * we want to use the policy of the current user not the "destination"
71 	 * user. This will enable us to prevent su to root but not to rlogin,
72 	 * telnet, rsh, ftp to root.
73 	 *
74 	 * description of problem: user name is the "destination" name. not
75 	 * the current name. The allow policy needs to be applied to the
76 	 * current name in the case of su. user is "root" in this case and
77 	 * we will be getting the root policy instead of the user policy.
78 	 */
79 	if (strcmp(pg, "su") == 0) {
80 		struct passwd *pw;
81 		uid_t uid;
82 		uid = getuid();
83 		pw = getpwuid(uid);
84 		if (pw == NULL)
85 			return (PAM_SYSTEM_ERR);
86 		user = pw->pw_name;
87 	}
88 
89 	if (user == 0 || *user == '\0' || (strcmp(user, "root") == 0))
90 		return (PAM_SUCCESS);
91 
92 	for (i = 0; i < argc; i++) {
93 		if (strcasecmp(argv[i], "debug") == 0)
94 			debug = 1;
95 		else if (strcasecmp(argv[i], "nowarn") == 0) {
96 			nowarn = 1;
97 			flags = flags | PAM_SILENT;
98 		} else if (strncmp(argv[i], "allow=", 6) == 0)
99 			error |= parse_allow_name(user, (char *)(argv[i]+6));
100 		else
101 			syslog(LOG_DEBUG, "illegal option %s", argv[i]);
102 	}
103 	return (error?PAM_SUCCESS:PAM_AUTH_ERR);
104 }
105 
106 static char *getname();
107 
108 static int
109 parse_allow_name(char *who, char *cp)
110 {
111 	char name[256];
112 
113 	/* catch "allow=" */
114 	if (*cp == '\0')
115 		return (0);
116 	while (cp) {
117 		cp = getname(cp, name);
118 		/* catch things such as =, and ,, */
119 		if (*name == '\0')
120 			continue;
121 		if (strcmp(who, name) == 0)
122 			return (1);
123 	}
124 	return (0);
125 }
126 
127 static char *
128 getname(char *cp, char *name)
129 {
130 	/* force name to be initially null string */
131 	*name = '\0';
132 
133 	/* end of string? */
134 	if (*cp == '\0')
135 		return ((char *)0);
136 	while (*cp) {
137 		/* end of name? */
138 		if (*cp == ',' || *cp == '\0')
139 			break;
140 		*name++ = *cp++;
141 	}
142 	/* make name into string */
143 	*name++ = '\0';
144 	return ((*cp == '\0')? (char *)0 : ++cp);
145 }
146