xref: /freebsd/contrib/openpam/modules/pam_unix/pam_unix.c (revision 4b2eaea43fec8e8792be611dea204071a10b655a)
1 /*-
2  * Copyright (c) 2002 Networks Associates Technology, Inc.
3  * All rights reserved.
4  *
5  * This software was developed for the FreeBSD Project by ThinkSec AS and
6  * Network Associates Laboratories, the Security Research Division of
7  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
8  * ("CBOSS"), as part of the DARPA CHATS research program.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. The name of the author may not be used to endorse or promote
19  *    products derived from this software without specific prior written
20  *    permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $P4: //depot/projects/openpam/modules/pam_unix/pam_unix.c#3 $
35  */
36 
37 #include <sys/param.h>
38 
39 #include <pwd.h>
40 #include <stdlib.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include <security/pam_modules.h>
46 #include <security/pam_appl.h>
47 
48 #ifndef _OPENPAM
49 static char password_prompt[] = "Password:";
50 #endif
51 
52 #ifndef PAM_EXTERN
53 #define PAM_EXTERN
54 #endif
55 
56 PAM_EXTERN int
57 pam_sm_authenticate(pam_handle_t *pamh, int flags,
58 	int argc, const char *argv[])
59 {
60 #ifndef _OPENPAM
61 	struct pam_conv *conv;
62 	struct pam_message msg;
63 	const struct pam_message *msgp;
64 	struct pam_response *resp;
65 #endif
66 	struct passwd *pwd;
67 	const char *user;
68 	char *crypt_password, *password;
69 	int pam_err, retry;
70 
71 	/* identify user */
72 	if ((pam_err = pam_get_user(pamh, &user, NULL)) != PAM_SUCCESS)
73 		return (pam_err);
74 	if ((pwd = getpwnam(user)) == NULL)
75 		return (PAM_USER_UNKNOWN);
76 
77 	/* get password */
78 #ifndef _OPENPAM
79 	pam_err = pam_get_item(pamh, PAM_CONV, (const void **)&conv);
80 	if (pam_err != PAM_SUCCESS)
81 		return (PAM_SYSTEM_ERR);
82 	msg.msg_style = PAM_PROMPT_ECHO_OFF;
83 	msg.msg = password_prompt;
84 	msgp = &msg;
85 #endif
86 	for (retry = 0; retry < 3; ++retry) {
87 #ifdef _OPENPAM
88 		pam_err = pam_get_authtok(pamh, PAM_AUTHTOK,
89 		    (const char **)&password, NULL);
90 #else
91 		resp = NULL;
92 		pam_err = (*conv->conv)(1, &msgp, &resp, conv->appdata_ptr);
93 		if (resp != NULL) {
94 			if (pam_err == PAM_SUCCESS)
95 				password = resp->resp;
96 			else
97 				free(resp->resp);
98 			free(resp);
99 		}
100 #endif
101 		if (pam_err == PAM_SUCCESS)
102 			break;
103 	}
104 	if (pam_err == PAM_CONV_ERR)
105 		return (pam_err);
106 	if (pam_err != PAM_SUCCESS)
107 		return (PAM_AUTH_ERR);
108 
109 	/* compare passwords */
110 	if ((!pwd->pw_passwd[0] && (flags & PAM_DISALLOW_NULL_AUTHTOK)) ||
111 	    (crypt_password = crypt(password, pwd->pw_passwd)) == NULL ||
112 	    strcmp(crypt_password, pwd->pw_passwd) != 0)
113 		pam_err = PAM_AUTH_ERR;
114 	else
115 		pam_err = PAM_SUCCESS;
116 #ifndef _OPENPAM
117 	free(password);
118 #endif
119 	return (pam_err);
120 }
121 
122 PAM_EXTERN int
123 pam_sm_setcred(pam_handle_t *pamh, int flags,
124 	int argc, const char *argv[])
125 {
126 
127 	return (PAM_SUCCESS);
128 }
129 
130 PAM_EXTERN int
131 pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
132 	int argc, const char *argv[])
133 {
134 
135 	return (PAM_SUCCESS);
136 }
137 
138 PAM_EXTERN int
139 pam_sm_open_session(pam_handle_t *pamh, int flags,
140 	int argc, const char *argv[])
141 {
142 
143 	return (PAM_SUCCESS);
144 }
145 
146 PAM_EXTERN int
147 pam_sm_close_session(pam_handle_t *pamh, int flags,
148 	int argc, const char *argv[])
149 {
150 
151 	return (PAM_SUCCESS);
152 }
153 
154 PAM_EXTERN int
155 pam_sm_chauthtok(pam_handle_t *pamh, int flags,
156 	int argc, const char *argv[])
157 {
158 
159 	return (PAM_SERVICE_ERR);
160 }
161 
162 #ifdef PAM_MODULE_ENTRY
163 PAM_MODULE_ENTRY("pam_unix");
164 #endif
165