1 /*	$OpenBSD: logutmp.c,v 1.10 2005/05/27 04:27:27 millert 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/in_systm.h>
37 #include <netinet/ip.h>
38 #include <netinet/tcp.h>
39 
40 #include <fcntl.h>
41 #include <unistd.h>
42 #include <stdlib.h>
43 #include <utmp.h>
44 #include <stdio.h>
45 #include <string.h>
46 #include <ttyent.h>
47 #include "extern.h"
48 
49 static int fd = -1;
50 static int topslot = -1;
51 
52 /*
53  * Special versions of login()/logout() which hold the utmp file open,
54  * for use with ftpd.
55  */
56 
57 void
ftpd_login(struct utmp * ut)58 ftpd_login(struct utmp *ut)
59 {
60 	struct utmp ubuf;
61 
62 	/*
63 	 * First, loop through /etc/ttys, if needed, to initialize the
64 	 * top of the tty slots, since ftpd has no tty.
65 	 */
66 	if (topslot < 0) {
67 		topslot = 0;
68 		while (getttyent() != (struct ttyent *)NULL)
69 			topslot++;
70 	}
71 	if ((topslot < 0) || ((fd < 0) &&
72 	    (fd = open(_PATH_UTMP, O_RDWR|O_CREAT, 0644)) < 0))
73 		return;
74 
75 	/*
76 	 * Now find a slot that's not in use...
77 	 */
78 	(void)lseek(fd, (off_t)(topslot * sizeof(struct utmp)), SEEK_SET);
79 
80 	while (1) {
81 		if (read(fd, &ubuf, sizeof(struct utmp)) ==
82 		    sizeof(struct utmp)) {
83 			if (!ubuf.ut_name[0]) {
84 				(void)lseek(fd, -(off_t)sizeof(struct utmp),
85 				    SEEK_CUR);
86 				break;
87 			}
88 			topslot++;
89 		} else {
90 			(void)lseek(fd, (off_t)(topslot *
91 			    sizeof(struct utmp)), SEEK_SET);
92 			break;
93 		}
94 	}
95 
96 	(void)write(fd, ut, sizeof(struct utmp));
97 }
98 
99 int
ftpd_logout(char * line)100 ftpd_logout(char *line)
101 {
102 	struct timeval tv;
103 	struct utmp ut;
104 	int rval;
105 
106 	rval = 0;
107 	if (fd < 0)
108 		return(rval);
109 
110 	(void)lseek(fd, 0, SEEK_SET);
111 
112 	while (read(fd, &ut, sizeof(struct utmp)) == sizeof(struct utmp)) {
113 		if (!ut.ut_name[0] ||
114 		    strncmp(ut.ut_line, line, UT_LINESIZE))
115 			continue;
116 		bzero(ut.ut_name, UT_NAMESIZE);
117 		bzero(ut.ut_host, UT_HOSTSIZE);
118 		gettimeofday(&tv, NULL);
119 		ut.ut_time = tv.tv_sec;
120 		(void)lseek(fd, -(off_t)sizeof(struct utmp), SEEK_CUR);
121 		(void)write(fd, &ut, sizeof(struct utmp));
122 		rval = 1;
123 	}
124 	return(rval);
125 }
126