xref: /titanic_41/usr/src/lib/pam_modules/sample/sample_authenticate.c (revision 59ac0c1669407488b67ae9e273667a340dccc611)
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 2003 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 <security/pam_appl.h>
30 #include <security/pam_modules.h>
31 #include <string.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <sys/types.h>
35 #include <pwd.h>
36 #include <syslog.h>
37 #include <libintl.h>
38 
39 #include "sample_utils.h"
40 
41 /*
42  *
43  * Sample module for pam_sm_authenticate.
44  *
45  * options -
46  *
47  *	debug
48  *	use_first_pass
49  *	try_first_pass
50  *	first_pass_good  (first password is always good when used with use/try)
51  *	first_pass_bad   (first password is always bad when used with use/try)
52  *	pass=foobar	 (set good password to "foobar". default good password
53  *			 is test)
54  *	always_fail	 always return PAM_AUTH_ERR
55  *	always_succeed   always return PAM_SUCCESS
56  *	always_ignore
57  *
58  *
59  */
60 
61 /*
62  * pam_sm_authenticate		- Authenticate user
63  */
64 /*ARGSUSED*/
65 int
66 pam_sm_authenticate(
67 	pam_handle_t		*pamh,
68 	int 			flags,
69 	int			argc,
70 	const char		**argv)
71 {
72 	char			*user;
73 	struct pam_conv 	*pam_convp;
74 	int			err, result = PAM_AUTH_ERR;
75 	struct pam_response 	*ret_resp = (struct pam_response *)0;
76 	char 			messages[PAM_MAX_NUM_MSG][PAM_MAX_MSG_SIZE];
77 	int			debug = 0;
78 	int			try_first_pass = 0;
79 	int			use_first_pass = 0;
80 	int			first_pass_good = 0;
81 	int			first_pass_bad = 0;
82 	int			i, num_msg;
83 	char			*firstpass, *password;
84 	char			the_password[64];
85 
86 	if (debug)
87 		syslog(LOG_DEBUG, "Sample Authentication\n");
88 
89 	(void) strcpy(the_password, "test");
90 
91 	for (i = 0; i < argc; i++) {
92 		if (strcmp(argv[i], "debug") == 0)
93 			debug = 1;
94 		else if (strcmp(argv[i], "try_first_pass") == 0)
95 			try_first_pass = 1;
96 		else if (strcmp(argv[i], "first_pass_good") == 0)
97 			first_pass_good = 1;
98 		else if (strcmp(argv[i], "first_pass_bad") == 0)
99 			first_pass_bad = 1;
100 		else if (strcmp(argv[i], "use_first_pass") == 0)
101 			use_first_pass = 1;
102 		else if (strcmp(argv[i], "always_fail") == 0)
103 			return (PAM_AUTH_ERR);
104 		else if (strcmp(argv[i], "always_succeed") == 0)
105 			return (PAM_SUCCESS);
106 		else if (strcmp(argv[i], "always_ignore") == 0)
107 			return (PAM_IGNORE);
108 		else if (sscanf(argv[i], "pass=%64s", the_password) == 1) {
109 			/*EMPTY*/;
110 		}
111 		else
112 			syslog(LOG_DEBUG, "illegal scheme option %s", argv[i]);
113 	}
114 
115 	err = pam_get_user(pamh, &user, NULL);
116 	if (err != PAM_SUCCESS)
117 		return (err);
118 
119 	err = pam_get_item(pamh, PAM_CONV, (void**) &pam_convp);
120 	if (err != PAM_SUCCESS)
121 		return (err);
122 
123 	(void) pam_get_item(pamh, PAM_AUTHTOK, (void **) &firstpass);
124 
125 	if (firstpass && (use_first_pass || try_first_pass)) {
126 
127 		if ((first_pass_good ||
128 			strncmp(firstpass, the_password,
129 				strlen(the_password)) == 0) &&
130 				!first_pass_bad) {
131 					result = PAM_SUCCESS;
132 					goto out;
133 		}
134 		if (use_first_pass) goto out;
135 	}
136 
137 	/*
138 	 * Get the password from the user
139 	 */
140 	if (firstpass) {
141 		(void) snprintf(messages[0], sizeof (messages[0]),
142 			dgettext(TEXT_DOMAIN, "TEST Password: "));
143 	} else {
144 		(void) snprintf(messages[0], sizeof (messages[0]),
145 			dgettext(TEXT_DOMAIN, "Password: "));
146 	}
147 	num_msg = 1;
148 	err = __get_authtok(pam_convp->conv,
149 				num_msg, messages, NULL, &ret_resp);
150 
151 	if (err != PAM_SUCCESS) {
152 		result = err;
153 		goto out;
154 	}
155 
156 	password = ret_resp->resp;
157 
158 	if (password == NULL) {
159 		result = PAM_AUTH_ERR;
160 		goto out;
161 	}
162 
163 	/* one last ditch attempt to "login" to TEST */
164 
165 	if (strncmp(password, the_password, strlen(the_password)) == 0) {
166 		result = PAM_SUCCESS;
167 		if (firstpass == NULL) {
168 			/* this is the first password, stash it away */
169 			(void) pam_set_item(pamh, PAM_AUTHTOK, password);
170 		}
171 	}
172 
173 out:
174 	if (num_msg > 0) {
175 		if (ret_resp != 0) {
176 			if (ret_resp->resp != 0) {
177 				/* avoid leaving password cleartext around */
178 				(void) memset(ret_resp->resp, 0,
179 					strlen(ret_resp->resp));
180 			}
181 			__free_resp(num_msg, ret_resp);
182 			ret_resp = 0;
183 		}
184 	}
185 
186 	return (result);
187 }
188