pam_lastlog.c revision 89748 
1/*-
2 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 * Copyright (c) 2001 Mark R V Murray
5 * All rights reserved.
6 * Copyright (c) 2001 Networks Associates Technologies, Inc.
7 * All rights reserved.
8 *
9 * Portions of this software were developed for the FreeBSD Project by
10 * ThinkSec AS and NAI Labs, the Security Research Division of Network
11 * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
12 * ("CBOSS"), as part of the DARPA CHATS research program.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 *    notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 *    notice, this list of conditions and the following disclaimer in the
21 *    documentation and/or other materials provided with the distribution.
22 * 3. The name of the author may not be used to endorse or promote
23 *    products derived from this software without specific prior written
24 *    permission.
25 * 4. Neither the name of the University nor the names of its contributors
26 *    may be used to endorse or promote products derived from this software
27 *    without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 */
41
42#include <sys/cdefs.h>
43__FBSDID("$FreeBSD: head/lib/libpam/modules/pam_lastlog/pam_lastlog.c 89748 2002-01-24 17:15:04Z des $");
44
45#define _BSD_SOURCE
46
47#include <sys/param.h>
48
49#include <fcntl.h>
50#include <libutil.h>
51#include <pwd.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55#include <syslog.h>
56#include <time.h>
57#include <unistd.h>
58#include <utmp.h>
59
60#define PAM_SM_AUTH
61#define PAM_SM_ACCOUNT
62#define PAM_SM_SESSION
63#define PAM_SM_PASSWORD
64
65#include <security/pam_modules.h>
66#include <pam_mod_misc.h>
67
68extern int login_access(const char *, const char *);
69
70PAM_EXTERN int
71pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const char **argv)
72{
73	struct options options;
74
75	pam_std_option(&options, NULL, argc, argv);
76
77	PAM_LOG("Options processed");
78
79	PAM_RETURN(PAM_IGNORE);
80}
81
82PAM_EXTERN int
83pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv)
84{
85	struct options options;
86
87	pam_std_option(&options, NULL, argc, argv);
88
89	PAM_LOG("Options processed");
90
91	PAM_RETURN(PAM_IGNORE);
92}
93
94PAM_EXTERN int
95pam_sm_acct_mgmt(pam_handle_t *pamh, int flags, int argc ,const char **argv)
96{
97	struct options options;
98
99	pam_std_option(&options, NULL, argc, argv);
100
101	PAM_LOG("Options processed");
102
103	PAM_RETURN(PAM_IGNORE);
104}
105
106PAM_EXTERN int
107pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc, const char **argv)
108{
109	struct options options;
110
111	pam_std_option(&options, NULL, argc, argv);
112
113	PAM_LOG("Options processed");
114
115	PAM_RETURN(PAM_IGNORE);
116}
117
118PAM_EXTERN int
119pam_sm_open_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
120{
121	struct options options;
122	struct passwd *pwd;
123	struct utmp utmp;
124	struct lastlog ll;
125	const char *rhost, *user, *tty;
126	char *buf;
127	off_t llpos;
128	int fd, pam_err;
129
130	pam_std_option(&options, NULL, argc, argv);
131
132	PAM_LOG("Options processed");
133
134	pam_err = pam_get_item(pamh, PAM_USER, (const void **)&user);
135	if (pam_err != PAM_SUCCESS)
136		PAM_RETURN(pam_err);
137	if (user == NULL || (pwd = getpwnam(user)) == NULL)
138		PAM_RETURN(PAM_SERVICE_ERR);
139	PAM_LOG("Got user: %s", user);
140
141	pam_err = pam_get_item(pamh, PAM_RHOST, (const void **)&rhost);
142	if (pam_err != PAM_SUCCESS)
143		PAM_RETURN(pam_err);
144
145	pam_err = pam_get_item(pamh, PAM_TTY, (const void **)&tty);
146	if (pam_err != PAM_SUCCESS)
147		PAM_RETURN(pam_err);
148	if (tty == NULL)
149		PAM_RETURN(PAM_SERVICE_ERR);
150
151	fd = open(_PATH_LASTLOG, O_RDWR, 0);
152	if (fd == -1) {
153		syslog(LOG_ERR, "cannot open %s: %m", _PATH_LASTLOG);
154		PAM_RETURN(PAM_SERVICE_ERR);
155	}
156
157	/*
158	 * Record session in lastlog(5).
159	 */
160	llpos = (off_t)(pwd->pw_uid * sizeof(ll));
161	if (lseek(fd, llpos, L_SET) != llpos)
162		goto file_err;
163	if ((flags & PAM_SILENT) == 0) {
164		if (read(fd, &ll, sizeof(ll)) == sizeof(ll) &&
165		    ll.ll_time != 0) {
166			asprintf(&buf, "Last login: %.*s ", 24 - 5,
167			    ctime(&ll.ll_time));
168			if (buf != NULL) {
169				pam_prompt(pamh, PAM_TEXT_INFO, buf, NULL);
170				free(buf);
171			}
172			if (*ll.ll_host != '\0')
173				asprintf(&buf, "from %.*s\n",
174				    (int)sizeof(ll.ll_host), ll.ll_host);
175			else
176				asprintf(&buf, "on %.*s\n",
177				    (int)sizeof(ll.ll_line), ll.ll_line);
178			if (buf != NULL) {
179				pam_prompt(pamh, PAM_TEXT_INFO, buf, NULL);
180				free(buf);
181			}
182		}
183		if (lseek(fd, llpos, L_SET) != llpos)
184			goto file_err;
185	}
186
187	bzero(&ll, sizeof(ll));
188	time(&ll.ll_time);
189
190	/* note: does not need to be NUL-terminated */
191	strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
192	if (rhost != NULL)
193		/* note: does not need to be NUL-terminated */
194		strncpy(ll.ll_host, rhost, sizeof(ll.ll_host));
195
196	if (write(fd, (char *)&ll, sizeof(ll)) != sizeof(ll) || close(fd) != 0)
197		goto file_err;
198
199	PAM_LOG("Login recorded in %s", _PATH_LASTLOG);
200
201	/*
202	 * Record session in utmp(5) and wtmp(5).
203	 */
204	bzero(&utmp, sizeof(utmp));
205	time(&utmp.ut_time);
206	/* note: does not need to be NUL-terminated */
207	strncpy(utmp.ut_name, user, sizeof(utmp.ut_name));
208	if (rhost != NULL)
209		strncpy(utmp.ut_host, rhost, sizeof(utmp.ut_host));
210	(void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
211	login(&utmp);
212
213	PAM_RETURN(PAM_IGNORE);
214
215 file_err:
216	syslog(LOG_ERR, "%s: %m", _PATH_LASTLOG);
217	close(fd);
218	PAM_RETURN(PAM_SERVICE_ERR);
219}
220
221PAM_EXTERN int
222pam_sm_close_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
223{
224	struct options options;
225
226	pam_std_option(&options, NULL, argc, argv);
227
228	PAM_LOG("Options processed");
229
230	PAM_RETURN(PAM_SUCCESS);
231}
232
233PAM_MODULE_ENTRY("pam_lastlog");
234