libexec/ftpd/logwtmp.c

   1 /*
   2  * Copyright (c) 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)logwtmp.c        8.1 (Berkeley) 6/4/93
  30  * $FreeBSD: src/libexec/ftpd/logwtmp.c,v 1.9.2.2 2002/08/08 12:24:54 yar Exp $
  31  */
  32
  33 #include <sys/types.h>
  34 #include <sys/stat.h>
  35 #include <netinet/in.h>
  36 #include <arpa/inet.h>
  37 #include <sys/socket.h>
  38
  39 #include <fcntl.h>
  40 #include <time.h>
  41 #include <netdb.h>
  42 #include <utmp.h>
  43 #include <unistd.h>
  44 #include <stdio.h>
  45 #include <string.h>
  46 #include <libutil.h>
  47 #include "extern.h"
  48
  49 static int fd = -1;
  50
  51 /*
  52  * Modified version of logwtmp that holds wtmp file open
  53  * after first call, for use with ftp (which may chroot
  54  * after login, but before logout).
  55  */
  56 void
  57 ftpd_logwtmp(char *line, char *name, struct sockaddr *addr)
  58 {
  59         struct utmp ut;
  60         struct stat buf;
  61         char host[UT_HOSTSIZE];
  62
  63         if (addr == NULL)
  64                 host[0] = '\0';
  65         else
  66                 realhostname_sa(host, sizeof(host), addr, addr->sa_len);
  67
  68         if (fd < 0 && (fd = open(_PATH_WTMP, O_WRONLY|O_APPEND, 0)) < 0)
  69                 return;
  70         if (fstat(fd, &buf) == 0) {
  71                 (void)strncpy(ut.ut_line, line, sizeof(ut.ut_line));
  72                 (void)strncpy(ut.ut_name, name, sizeof(ut.ut_name));
  73                 (void)strncpy(ut.ut_host, host, sizeof(ut.ut_host));
  74                 (void)time(&ut.ut_time);
  75                 if (write(fd, &ut, sizeof(struct utmp)) !=
  76                     sizeof(struct utmp))
  77                         (void)ftruncate(fd, buf.st_size);
  78         }
  79 }