1/*	$OpenBSD: logutmp.c,v 1.14 2019/06/28 13:32:53 deraadt Exp $	*/
2/*
3 * Portions Copyright (c) 1988, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 * Portions Copyright (c) 1996, Jason Downs.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/types.h>
33#include <sys/time.h>
34#include <sys/socket.h>
35#include <netinet/in.h>
36#include <netinet/ip.h>
37#include <netinet/tcp.h>
38
39#include <fcntl.h>
40#include <unistd.h>
41#include <stdlib.h>
42#include <utmp.h>
43#include <stdio.h>
44#include <string.h>
45#include <ttyent.h>
46
47#include "monitor.h"
48#include "extern.h"
49
50static int fd = -1;
51static int topslot = -1;
52
53/*
54 * Special versions of login()/logout() which hold the utmp file open,
55 * for use with ftpd.
56 */
57
58void
59ftpd_login(struct utmp *ut)
60{
61	struct utmp ubuf;
62
63	/*
64	 * First, loop through /etc/ttys, if needed, to initialize the
65	 * top of the tty slots, since ftpd has no tty.
66	 */
67	if (topslot < 0) {
68		topslot = 0;
69		while (getttyent() != (struct ttyent *)NULL)
70			topslot++;
71	}
72	if ((topslot < 0) || ((fd < 0) &&
73	    (fd = open(_PATH_UTMP, O_RDWR|O_CREAT, 0644)) == -1))
74		return;
75
76	/*
77	 * Now find a slot that's not in use...
78	 */
79	(void)lseek(fd, (off_t)topslot * sizeof(struct utmp), SEEK_SET);
80
81	while (1) {
82		if (read(fd, &ubuf, sizeof(struct utmp)) ==
83		    sizeof(struct utmp)) {
84			if (!ubuf.ut_name[0]) {
85				(void)lseek(fd, -(off_t)sizeof(struct utmp),
86				    SEEK_CUR);
87				break;
88			}
89			topslot++;
90		} else {
91			(void)lseek(fd, (off_t)topslot * sizeof(struct utmp),
92			    SEEK_SET);
93			break;
94		}
95	}
96
97	(void)write(fd, ut, sizeof(struct utmp));
98}
99
100int
101ftpd_logout(char *line)
102{
103	struct timeval tv;
104	struct utmp ut;
105	int rval;
106
107	rval = 0;
108	if (fd < 0)
109		return(rval);
110
111	(void)lseek(fd, 0, SEEK_SET);
112
113	while (read(fd, &ut, sizeof(struct utmp)) == sizeof(struct utmp)) {
114		if (!ut.ut_name[0] ||
115		    strncmp(ut.ut_line, line, UT_LINESIZE))
116			continue;
117		bzero(ut.ut_name, UT_NAMESIZE);
118		bzero(ut.ut_host, UT_HOSTSIZE);
119		gettimeofday(&tv, NULL);
120		ut.ut_time = tv.tv_sec;
121		(void)lseek(fd, -(off_t)sizeof(struct utmp), SEEK_CUR);
122		(void)write(fd, &ut, sizeof(struct utmp));
123		rval = 1;
124	}
125	return(rval);
126}
127