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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <sys/types.h>
29 #include <sys/varargs.h>
30 #include <string.h>
31 #include <syslog.h>
32 #include <stdlib.h>
33 
34 #include <security/pam_appl.h>
35 #include <security/pam_modules.h>
36 #include <security/pam_impl.h>
37 
38 #include <libintl.h>
39 #include <passwdutil.h>
40 
41 #include <smbsrv/libsmb.h>
42 
43 /*PRINTFLIKE3*/
44 static void
45 error(boolean_t nowarn, pam_handle_t *pamh, char *fmt, ...)
46 {
47 	va_list ap;
48 	char message[PAM_MAX_MSG_SIZE];
49 
50 	if (nowarn)
51 		return;
52 
53 	va_start(ap, fmt);
54 	(void) vsnprintf(message, sizeof (message), fmt, ap);
55 	(void) __pam_display_msg(pamh, PAM_ERROR_MSG, 1, &message,
56 	    NULL);
57 	va_end(ap);
58 }
59 
60 /*PRINTFLIKE3*/
61 static void
62 info(boolean_t nowarn, pam_handle_t *pamh, char *fmt, ...)
63 {
64 	va_list ap;
65 	char message[PAM_MAX_MSG_SIZE];
66 
67 	if (nowarn)
68 		return;
69 
70 	va_start(ap, fmt);
71 	(void) vsnprintf(message, sizeof (message), fmt, ap);
72 	(void) __pam_display_msg(pamh, PAM_TEXT_INFO, 1, &message,
73 	    NULL);
74 	va_end(ap);
75 }
76 
77 int
78 pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc, const char **argv)
79 {
80 	boolean_t debug = B_FALSE;
81 	boolean_t nowarn = B_FALSE;
82 	pwu_repository_t files_rep;
83 	char *user, *local_user;
84 	char *newpw;
85 	char *service;
86 	int privileged;
87 	int res;
88 	int i;
89 
90 	for (i = 0; i < argc; i++) {
91 		if (strcmp(argv[i], "debug") == 0)
92 			debug = B_TRUE;
93 		else if (strcmp(argv[i], "nowarn") == 0)
94 			nowarn = B_TRUE;
95 	}
96 
97 	if ((flags & PAM_PRELIM_CHECK) != 0)
98 		return (PAM_IGNORE);
99 
100 	if ((flags & PAM_UPDATE_AUTHTOK) == 0)
101 		return (PAM_SYSTEM_ERR);
102 
103 	if ((flags & PAM_SILENT) != 0)
104 		nowarn = B_TRUE;
105 
106 	if (debug)
107 		__pam_log(LOG_AUTH | LOG_DEBUG,
108 		    "pam_smb_passwd: storing authtok");
109 
110 	(void) pam_get_item(pamh, PAM_SERVICE, (void **)&service);
111 	(void) pam_get_item(pamh, PAM_USER, (void **)&user);
112 
113 	if (user == NULL || *user == '\0') {
114 		__pam_log(LOG_AUTH | LOG_ERR,
115 		    "pam_smb_passwd: username is empty");
116 		return (PAM_USER_UNKNOWN);
117 	}
118 
119 	(void) pam_get_item(pamh, PAM_AUTHTOK, (void **)&newpw);
120 	if (newpw == NULL) {
121 		/*
122 		 * A module on the stack has removed PAM_AUTHTOK. We fail
123 		 */
124 		return (PAM_AUTHTOK_ERR);
125 	}
126 
127 	/* Check to see if this is a local user */
128 	files_rep.type = "files";
129 	files_rep.scope = NULL;
130 	files_rep.scope_len = 0;
131 	res = __user_to_authenticate(user, &files_rep, &local_user,
132 	    &privileged);
133 	if (res != PWU_SUCCESS) {
134 		switch (res) {
135 		case PWU_NOT_FOUND:
136 			/* if not a local user, ignore */
137 			if (debug) {
138 				__pam_log(LOG_AUTH | LOG_DEBUG,
139 				    "pam_smb_passwd: %s is not local", user);
140 			}
141 			return (PAM_IGNORE);
142 		case PWU_DENIED:
143 			return (PAM_PERM_DENIED);
144 		}
145 		return (PAM_SYSTEM_ERR);
146 	}
147 
148 	smb_pwd_init(B_FALSE);
149 
150 	res = smb_pwd_setpasswd(user, newpw);
151 
152 	smb_pwd_fini();
153 
154 	/*
155 	 * now map the various return states to user messages
156 	 * and PAM return codes.
157 	 */
158 	switch (res) {
159 	case SMB_PWE_SUCCESS:
160 		info(nowarn, pamh, dgettext(TEXT_DOMAIN,
161 		    "%s: SMB password successfully changed for %s"),
162 		    service, user);
163 		return (PAM_SUCCESS);
164 
165 	case SMB_PWE_STAT_FAILED:
166 		__pam_log(LOG_AUTH | LOG_ERR,
167 		    "%s: stat of SMB password file failed", service);
168 		return (PAM_SYSTEM_ERR);
169 
170 	case SMB_PWE_OPEN_FAILED:
171 	case SMB_PWE_WRITE_FAILED:
172 	case SMB_PWE_CLOSE_FAILED:
173 	case SMB_PWE_UPDATE_FAILED:
174 		error(nowarn, pamh, dgettext(TEXT_DOMAIN,
175 		    "%s: Unexpected failure. SMB password database unchanged."),
176 		    service);
177 		return (PAM_SYSTEM_ERR);
178 
179 	case SMB_PWE_BUSY:
180 		error(nowarn, pamh, dgettext(TEXT_DOMAIN,
181 		    "%s: SMB password database busy. Try again later."),
182 		    service);
183 
184 		return (PAM_AUTHTOK_LOCK_BUSY);
185 
186 	case SMB_PWE_USER_UNKNOWN:
187 		error(nowarn, pamh, dgettext(TEXT_DOMAIN,
188 		    "%s: %s does not exist."), service, user);
189 		return (PAM_USER_UNKNOWN);
190 
191 	case SMB_PWE_USER_DISABLE:
192 		error(nowarn, pamh, dgettext(TEXT_DOMAIN,
193 		    "%s: %s is disable. SMB password database unchanged."),
194 		    service, user);
195 		return (PAM_IGNORE);
196 
197 	case SMB_PWE_DENIED:
198 		return (PAM_PERM_DENIED);
199 
200 	default:
201 		res = PAM_SYSTEM_ERR;
202 		break;
203 	}
204 
205 	return (res);
206 }
207