pam_lastlog.c revision 90229 
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 90229 2002-02-05 06:08:26Z 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_appl.h>
66#include <security/pam_modules.h>
67#include <security/pam_mod_misc.h>
68
69extern int login_access(const char *, const char *);
70
71PAM_EXTERN int
72pam_sm_authenticate(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
73{
74	struct options options;
75
76	pam_std_option(&options, NULL, argc, argv);
77
78	PAM_LOG("Options processed");
79
80	PAM_RETURN(PAM_IGNORE);
81}
82
83PAM_EXTERN int
84pam_sm_setcred(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
85{
86	struct options options;
87
88	pam_std_option(&options, NULL, argc, argv);
89
90	PAM_LOG("Options processed");
91
92	PAM_RETURN(PAM_IGNORE);
93}
94
95PAM_EXTERN int
96pam_sm_acct_mgmt(pam_handle_t *pamh __unused, int flags __unused, int argc ,const char **argv)
97{
98	struct options options;
99
100	pam_std_option(&options, NULL, argc, argv);
101
102	PAM_LOG("Options processed");
103
104	PAM_RETURN(PAM_IGNORE);
105}
106
107PAM_EXTERN int
108pam_sm_chauthtok(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
109{
110	struct options options;
111
112	pam_std_option(&options, NULL, argc, argv);
113
114	PAM_LOG("Options processed");
115
116	PAM_RETURN(PAM_IGNORE);
117}
118
119PAM_EXTERN int
120pam_sm_open_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
121{
122	struct options options;
123	struct passwd *pwd;
124	struct utmp utmp;
125	struct lastlog ll;
126	const char *rhost, *user, *tty;
127	char *buf;
128	off_t llpos;
129	int fd, pam_err;
130
131	pam_std_option(&options, NULL, argc, argv);
132
133	PAM_LOG("Options processed");
134
135	pam_err = pam_get_item(pamh, PAM_USER, (const void **)&user);
136	if (pam_err != PAM_SUCCESS)
137		PAM_RETURN(pam_err);
138	if (user == NULL || (pwd = getpwnam(user)) == NULL)
139		PAM_RETURN(PAM_SERVICE_ERR);
140	PAM_LOG("Got user: %s", user);
141
142	pam_err = pam_get_item(pamh, PAM_RHOST, (const void **)&rhost);
143	if (pam_err != PAM_SUCCESS)
144		PAM_RETURN(pam_err);
145
146	pam_err = pam_get_item(pamh, PAM_TTY, (const void **)&tty);
147	if (pam_err != PAM_SUCCESS)
148		PAM_RETURN(pam_err);
149	if (tty == NULL)
150		PAM_RETURN(PAM_SERVICE_ERR);
151
152	fd = open(_PATH_LASTLOG, O_RDWR, 0);
153	if (fd == -1) {
154		syslog(LOG_ERR, "cannot open %s: %m", _PATH_LASTLOG);
155		PAM_RETURN(PAM_SERVICE_ERR);
156	}
157
158	/*
159	 * Record session in lastlog(5).
160	 */
161	llpos = (off_t)(pwd->pw_uid * sizeof(ll));
162	if (lseek(fd, llpos, L_SET) != llpos)
163		goto file_err;
164	if ((flags & PAM_SILENT) == 0) {
165		if (read(fd, &ll, sizeof(ll)) == sizeof(ll) &&
166		    ll.ll_time != 0) {
167			asprintf(&buf, "Last login: %.*s ", 24 - 5,
168			    ctime(&ll.ll_time));
169			if (buf != NULL) {
170				pam_prompt(pamh, PAM_TEXT_INFO, buf, NULL);
171				free(buf);
172			}
173			if (*ll.ll_host != '\0')
174				asprintf(&buf, "from %.*s\n",
175				    (int)sizeof(ll.ll_host), ll.ll_host);
176			else
177				asprintf(&buf, "on %.*s\n",
178				    (int)sizeof(ll.ll_line), ll.ll_line);
179			if (buf != NULL) {
180				pam_prompt(pamh, PAM_TEXT_INFO, buf, NULL);
181				free(buf);
182			}
183		}
184		if (lseek(fd, llpos, L_SET) != llpos)
185			goto file_err;
186	}
187
188	bzero(&ll, sizeof(ll));
189	time(&ll.ll_time);
190
191	/* note: does not need to be NUL-terminated */
192	strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
193	if (rhost != NULL)
194		/* note: does not need to be NUL-terminated */
195		strncpy(ll.ll_host, rhost, sizeof(ll.ll_host));
196
197	if (write(fd, (char *)&ll, sizeof(ll)) != sizeof(ll) || close(fd) != 0)
198		goto file_err;
199
200	PAM_LOG("Login recorded in %s", _PATH_LASTLOG);
201
202	/*
203	 * Record session in utmp(5) and wtmp(5).
204	 */
205	bzero(&utmp, sizeof(utmp));
206	time(&utmp.ut_time);
207	/* note: does not need to be NUL-terminated */
208	strncpy(utmp.ut_name, user, sizeof(utmp.ut_name));
209	if (rhost != NULL)
210		strncpy(utmp.ut_host, rhost, sizeof(utmp.ut_host));
211	(void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
212	login(&utmp);
213
214	PAM_RETURN(PAM_IGNORE);
215
216 file_err:
217	syslog(LOG_ERR, "%s: %m", _PATH_LASTLOG);
218	close(fd);
219	PAM_RETURN(PAM_SERVICE_ERR);
220}
221
222PAM_EXTERN int
223pam_sm_close_session(pam_handle_t *pamh __unused, int flags __unused, int argc, const char **argv)
224{
225	struct options options;
226
227	pam_std_option(&options, NULL, argc, argv);
228
229	PAM_LOG("Options processed");
230
231	PAM_RETURN(PAM_SUCCESS);
232}
233
234PAM_MODULE_ENTRY("pam_lastlog");
235