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/*-
* Copyright (c) 2009 Ed Schouten <ed@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <pwd.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <ulog.h>
/*
* This setuid helper utility writes user login records to disk.
* Unprivileged processes are not capable of writing records to utmpx,
* but we do want to allow this for pseudo-terminals. Because a file
* descriptor to a pseudo-terminal master device can only be obtained by
* processes using the pseudo-terminal, we expect such a descriptor on
* stdin.
*
* It uses the real user ID of the calling process to determine the
* username. It does allow users to log arbitrary hostnames.
*/
int
main(int argc, char *argv[])
{
const char *line, *user, *host;
/* Device line name. */
if ((line = ptsname(STDIN_FILENO)) == NULL)
return (EX_USAGE);
if ((argc == 2 || argc == 3) && strcmp(argv[1], "login") == 0) {
/* Username. */
user = user_from_uid(getuid(), 1);
if (user == NULL)
return (EX_OSERR);
/* Hostname. */
host = argc == 3 ? argv[2] : NULL;
ulog_login(line, user, host);
return (EX_OK);
} else if (argc == 2 && strcmp(argv[1], "logout") == 0) {
ulog_logout(line);
return (EX_OK);
}
return (EX_USAGE);
}
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