pam_nologin.c revision 89760 
1/*-
2 * Copyright 2001 Mark R V Murray
3 * All rights reserved.
4 * Copyright (c) 2001 Networks Associates Technologies, Inc.
5 * All rights reserved.
6 *
7 * Portions of this software were developed for the FreeBSD Project by
8 * ThinkSec AS and NAI Labs, the Security Research Division of Network
9 * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
10 * ("CBOSS"), as part of the DARPA CHATS research program.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. The name of the author may not be used to endorse or promote
21 *    products derived from this software without specific prior written
22 *    permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: head/lib/libpam/modules/pam_nologin/pam_nologin.c 89760 2002-01-24 18:37:17Z markm $");
39
40#include <sys/types.h>
41#include <sys/stat.h>
42#include <fcntl.h>
43#include <login_cap.h>
44#include <pwd.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include <unistd.h>
48
49#define PAM_SM_AUTH
50#define PAM_SM_ACCOUNT
51#define PAM_SM_SESSION
52#define PAM_SM_PASSWORD
53
54#include <security/_pam_macros.h>
55#include <security/pam_modules.h>
56#include "pam_mod_misc.h"
57
58#define	NOLOGIN	"/var/run/nologin"
59
60static char nologin_def[] = NOLOGIN;
61
62PAM_EXTERN int
63pam_sm_authenticate(pam_handle_t *pamh, int flags __unused, int argc, const char **argv)
64{
65	login_cap_t *lc;
66	struct options options;
67	struct passwd *pwd;
68	struct stat st;
69	int retval, fd;
70	const char *user, *nologin;
71	char *mtmp;
72
73	pam_std_option(&options, NULL, argc, argv);
74
75	PAM_LOG("Options processed");
76
77	retval = pam_get_user(pamh, &user, NULL);
78	if (retval != PAM_SUCCESS)
79		PAM_RETURN(retval);
80
81	PAM_LOG("Got user: %s", user);
82
83	lc = login_getclass(NULL);
84	nologin = login_getcapstr(lc, "nologin", nologin_def, nologin_def);
85	login_close(lc);
86	lc = NULL;
87
88	fd = open(nologin, O_RDONLY, 0);
89	if (fd < 0)
90		PAM_RETURN(PAM_SUCCESS);
91
92	PAM_LOG("Opened %s file", NOLOGIN);
93
94	pwd = getpwnam(user);
95	if (pwd && pwd->pw_uid == 0)
96		retval = PAM_SUCCESS;
97	else {
98		if (!pwd)
99			retval = PAM_USER_UNKNOWN;
100		else
101			retval = PAM_AUTH_ERR;
102	}
103
104	if (fstat(fd, &st) < 0)
105		PAM_RETURN(retval);
106
107	mtmp = malloc(st.st_size + 1);
108	if (mtmp != NULL) {
109		read(fd, mtmp, st.st_size);
110		mtmp[st.st_size] = '\0';
111		pam_prompt(pamh, PAM_ERROR_MSG, mtmp, NULL);
112		free(mtmp);
113	}
114
115	if (retval != PAM_SUCCESS)
116		PAM_VERBOSE_ERROR("Administrator refusing you: %s", NOLOGIN);
117
118	PAM_RETURN(retval);
119}
120
121PAM_EXTERN int
122pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
123{
124	struct options options;
125
126	pam_std_option(&options, NULL, argc, argv);
127
128	PAM_LOG("Options processed");
129
130	PAM_RETURN(PAM_SUCCESS);
131}
132
133PAM_EXTERN int
134pam_sm_acct_mgmt(pam_handle_t *pamh __unused, int flags __unused, int argc ,const char **argv)
135{
136	struct options options;
137
138	pam_std_option(&options, NULL, argc, argv);
139
140	PAM_LOG("Options processed");
141
142	PAM_RETURN(PAM_IGNORE);
143}
144
145PAM_EXTERN int
146pam_sm_chauthtok(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
147{
148	struct options options;
149
150	pam_std_option(&options, NULL, argc, argv);
151
152	PAM_LOG("Options processed");
153
154	PAM_RETURN(PAM_IGNORE);
155}
156
157PAM_EXTERN int
158pam_sm_open_session(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
159{
160	struct options options;
161
162	pam_std_option(&options, NULL, argc, argv);
163
164	PAM_LOG("Options processed");
165
166	PAM_RETURN(PAM_IGNORE);
167}
168
169PAM_EXTERN int
170pam_sm_close_session(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
171{
172	struct options options;
173
174	pam_std_option(&options, NULL, argc, argv);
175
176	PAM_LOG("Options processed");
177
178	PAM_RETURN(PAM_IGNORE);
179}
180
181PAM_MODULE_ENTRY("pam_nologin");
182