1 /* $NetBSD: pam_unix.c,v 1.8 2023/06/30 21:46:21 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
5 * Copyright (c) 2004-2015 Dag-Erling Smørgrav
6 * All rights reserved.
7 *
8 * This software was developed for the FreeBSD Project by ThinkSec AS and
9 * Network Associates Laboratories, the Security Research Division of
10 * Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
11 * ("CBOSS"), as part of the DARPA CHATS research program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. The name of the author may not be used to endorse or promote
22 * products derived from this software without specific prior written
23 * permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38 #ifdef HAVE_CONFIG_H
39 # include "config.h"
40 #endif
41
42 #include <sys/param.h>
43
44 #include <pwd.h>
45 #include <stdlib.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <unistd.h>
49
50 #ifdef HAVE_CRYPT_H
51 # include <crypt.h>
52 #endif
53
54 #include <security/pam_modules.h>
55 #include <security/pam_appl.h>
56
57 #ifndef OPENPAM
58 static char password_prompt[] = "Password:";
59 #endif
60
61 #ifndef PAM_EXTERN
62 #define PAM_EXTERN
63 #endif
64
65 PAM_EXTERN int
pam_sm_authenticate(pam_handle_t * pamh,int flags,int argc,const char * argv[])66 pam_sm_authenticate(pam_handle_t *pamh, int flags,
67 int argc, const char *argv[])
68 {
69 #ifndef OPENPAM
70 struct pam_conv *conv;
71 struct pam_message msg;
72 const struct pam_message *msgp;
73 struct pam_response *resp;
74 #endif
75 struct passwd *pwd;
76 const char *user;
77 const char *crypt_password, *password;
78 int pam_err, retry;
79
80 (void)argc;
81 (void)argv;
82
83 /* identify user */
84 if ((pam_err = pam_get_user(pamh, &user, NULL)) != PAM_SUCCESS)
85 return (pam_err);
86 if ((pwd = getpwnam(user)) == NULL)
87 return (PAM_USER_UNKNOWN);
88
89 /* get password */
90 #ifndef OPENPAM
91 pam_err = pam_get_item(pamh, PAM_CONV, (const void **)&conv);
92 if (pam_err != PAM_SUCCESS)
93 return (PAM_SYSTEM_ERR);
94 msg.msg_style = PAM_PROMPT_ECHO_OFF;
95 msg.msg = password_prompt;
96 msgp = &msg;
97 #endif
98 for (retry = 0; retry < 3; ++retry) {
99 #ifdef OPENPAM
100 pam_err = pam_get_authtok(pamh, PAM_AUTHTOK,
101 &password, NULL);
102 #else
103 resp = NULL;
104 pam_err = (*conv->conv)(1, &msgp, &resp, conv->appdata_ptr);
105 if (resp != NULL) {
106 if (pam_err == PAM_SUCCESS)
107 password = resp->resp;
108 else
109 free(resp->resp);
110 free(resp);
111 }
112 #endif
113 if (pam_err == PAM_SUCCESS)
114 break;
115 }
116 if (pam_err == PAM_CONV_ERR)
117 return (pam_err);
118 if (pam_err != PAM_SUCCESS)
119 return (PAM_AUTH_ERR);
120
121 /* compare passwords */
122 if ((!pwd->pw_passwd[0] && (flags & PAM_DISALLOW_NULL_AUTHTOK)) ||
123 (crypt_password = crypt(password, pwd->pw_passwd)) == NULL ||
124 strcmp(crypt_password, pwd->pw_passwd) != 0)
125 pam_err = PAM_AUTH_ERR;
126 else
127 pam_err = PAM_SUCCESS;
128 #ifndef OPENPAM
129 free(password);
130 #endif
131 return (pam_err);
132 }
133
134 PAM_EXTERN int
pam_sm_setcred(pam_handle_t * pamh,int flags,int argc,const char * argv[])135 pam_sm_setcred(pam_handle_t *pamh, int flags,
136 int argc, const char *argv[])
137 {
138
139 (void)pamh;
140 (void)flags;
141 (void)argc;
142 (void)argv;
143 return (PAM_SUCCESS);
144 }
145
146 PAM_EXTERN int
pam_sm_acct_mgmt(pam_handle_t * pamh,int flags,int argc,const char * argv[])147 pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
148 int argc, const char *argv[])
149 {
150
151 (void)pamh;
152 (void)flags;
153 (void)argc;
154 (void)argv;
155 return (PAM_SUCCESS);
156 }
157
158 PAM_EXTERN int
pam_sm_open_session(pam_handle_t * pamh,int flags,int argc,const char * argv[])159 pam_sm_open_session(pam_handle_t *pamh, int flags,
160 int argc, const char *argv[])
161 {
162
163 (void)pamh;
164 (void)flags;
165 (void)argc;
166 (void)argv;
167 return (PAM_SUCCESS);
168 }
169
170 PAM_EXTERN int
pam_sm_close_session(pam_handle_t * pamh,int flags,int argc,const char * argv[])171 pam_sm_close_session(pam_handle_t *pamh, int flags,
172 int argc, const char *argv[])
173 {
174
175 (void)pamh;
176 (void)flags;
177 (void)argc;
178 (void)argv;
179 return (PAM_SUCCESS);
180 }
181
182 PAM_EXTERN int
pam_sm_chauthtok(pam_handle_t * pamh,int flags,int argc,const char * argv[])183 pam_sm_chauthtok(pam_handle_t *pamh, int flags,
184 int argc, const char *argv[])
185 {
186
187 (void)pamh;
188 (void)flags;
189 (void)argc;
190 (void)argv;
191 return (PAM_SERVICE_ERR);
192 }
193
194 #ifdef PAM_MODULE_ENTRY
195 PAM_MODULE_ENTRY("pam_unix");
196 #endif
197