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/* $OpenBSD: login.c,v 1.11 2015/12/28 20:11:36 guenther Exp $ */ |
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/* |
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* Copyright (c) 1988, 1993 |
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* The Regents of the University of California. All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* 3. Neither the name of the University nor the names of its contributors |
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* may be used to endorse or promote products derived from this software |
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* without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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*/ |
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#include <sys/types.h> |
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#include <fcntl.h> |
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#include <unistd.h> |
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#include <stdlib.h> |
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#include <utmp.h> |
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#include <stdio.h> |
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#include <string.h> |
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#include "util.h" |
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void |
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login(struct utmp *utp) |
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{ |
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struct utmp old_ut; |
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int fd, tty; |
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off_t pos; |
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tty = ttyslot(); |
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✓✗✓✗
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if (tty > 0 && (fd = open(_PATH_UTMP, O_RDWR|O_CREAT|O_CLOEXEC, 0644)) |
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>= 0) { |
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/* |
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* Prevent luser from zero'ing out ut_host. |
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* If the new ut_line is empty but the old one is not |
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* and ut_line and ut_name match, preserve the old ut_line. |
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*/ |
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pos = (off_t)tty * sizeof(struct utmp); |
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✓✗✗✗
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if (utp->ut_host[0] == '\0' && |
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pread(fd, &old_ut, sizeof(struct utmp), pos) == |
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✓✗ |
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sizeof(struct utmp) && |
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✗✓ |
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old_ut.ut_host[0] != '\0' && |
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strncmp(old_ut.ut_line, utp->ut_line, UT_LINESIZE) == 0 && |
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strncmp(old_ut.ut_name, utp->ut_name, UT_NAMESIZE) == 0) |
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(void)memcpy(utp->ut_host, old_ut.ut_host, UT_HOSTSIZE); |
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(void)pwrite(fd, utp, sizeof(struct utmp), pos); |
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(void)close(fd); |
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} |
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✓✗ |
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if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND|O_CLOEXEC)) >= 0) { |
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(void)write(fd, utp, sizeof(struct utmp)); |
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(void)close(fd); |
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} |
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} |