1 /* $OpenBSD: logout.c,v 1.10 2019/06/28 13:32:43 deraadt Exp $ */ 2 /* 3 * Copyright (c) 1988, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/types.h> 32 #include <sys/time.h> 33 34 #include <fcntl.h> 35 #include <utmp.h> 36 #include <unistd.h> 37 #include <stdlib.h> 38 #include <string.h> 39 40 #include "util.h" 41 42 typedef struct utmp UTMP; 43 44 int 45 logout(const char *line) 46 { 47 int fd, rval; 48 UTMP ut; 49 50 if ((fd = open(_PATH_UTMP, O_RDWR|O_CLOEXEC)) == -1) 51 return(0); 52 rval = 0; 53 while (read(fd, &ut, sizeof(UTMP)) == sizeof(UTMP)) { 54 if (!ut.ut_name[0] || strncmp(ut.ut_line, line, UT_LINESIZE)) 55 continue; 56 memset(ut.ut_name, 0, UT_NAMESIZE); 57 memset(ut.ut_host, 0, UT_HOSTSIZE); 58 (void)time(&ut.ut_time); 59 (void)lseek(fd, -(off_t)sizeof(UTMP), SEEK_CUR); 60 (void)write(fd, &ut, sizeof(UTMP)); 61 rval = 1; 62 } 63 (void)close(fd); 64 return(rval); 65 } 66