testcases/kernel/syscalls/fchdir/fchdir03.c

/*
 *
 * Copyright (C) Bull S.A. 2001
 * Copyright (c) International Business Machines  Corp., 2001
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program;  if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * NAME
 *	fchdir03
 *
 * DESCRIPTION
 *	Testcase for testing that fchdir(2) sets EACCES errno
 *
 * ALGORITHM
 *	1.	create a child process, sets its uid to ltpuser1
 *	2.	this child creates a directory with perm 400,
 *	3.	this child opens the directory and gets a file descriptor
 *	4.	this child attempts to fchdir(2) to the directory created in 2.
 *		and expects to get an EACCES.
 *	5.	finally this child checks the return code,
 *		resets the process ID to root and calls cleanup.
 *
 * USAGE:  <for command-line>
 *  fchdir03 [-c n] [-e] [-i n] [-I x] [-P x] [-t]
 *     where,  -c n : Run n copies concurrently.
 *             -e   : Turn on errno logging.
 *             -i n : Execute test n times.
 *             -I x : Execute test for x seconds.
 *             -P x : Pause for x seconds between iterations.
 *             -t   : Turn on syscall timing.
 *
 * HISTORY
 *	04/2002 Ported by Jacky Malcles
 *
 * RESTRICTIONS
 *	This test must be run as root.
 */

#include "test.h"

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

char *TCID = "fchdir03";
int TST_TOTAL = 1;

void setup(void);
void cleanup(void);

char user1name[] = "nobody";

char good_dir[100];
int fd;

struct passwd *ltpuser1;

extern struct passwd *my_getpwnam(char *);

int main(int ac, char **av)
{
	int lc;
	const char *msg;

	pid_t pid;
	int status;

	if ((msg = parse_opts(ac, av, NULL, NULL)) != NULL)
		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);

	setup();

	for (lc = 0; TEST_LOOPING(lc); lc++) {
		tst_count = 0;

		if ((pid = FORK_OR_VFORK()) == -1)
			tst_brkm(TBROK, cleanup, "fork failed");

		if (pid == 0) {
			/*
			 * set the child's ID to ltpuser1 using seteuid()
			 * so that the ID can be changed back after the
			 * TEST call is made.
			 */
			if (seteuid(ltpuser1->pw_uid) != 0) {
				perror("setreuid failed in child #1");
				exit(1);
			}
			if (mkdir(good_dir, 00400) != 0) {
				perror("mkdir failed in child #1");
				exit(1);
			}
			if ((fd = open(good_dir, O_RDONLY)) == -1) {
				perror("opening directory failed");
			}

			TEST(fchdir(fd));

			if (TEST_RETURN != -1) {
				printf("Call succeeded unexpectedly\n");
				exit(1);
			} else if (TEST_ERRNO != EACCES) {
				printf("Expected %d - got %d\n",
				       EACCES, TEST_ERRNO);
				exit(1);
			} else
				printf("Got EACCES as expected\n");

			/* reset the UID to root */
			if (setuid(0) == -1)
				perror("setuid(0) failed");

		} else {
			if (wait(&status) == -1)
				tst_brkm(TBROK | TERRNO, cleanup,
					 "wait failed");
			else if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
				tst_brkm(TBROK, cleanup,
					 "child exited abnormally (wait status = "
					 "%d", status);
			else {
				/* let the child carry on */
				exit(0);
			}
		}

		if (rmdir(good_dir) == -1)
			tst_brkm(TBROK, cleanup, "rmdir failed");

	}
	cleanup();

	tst_exit();
}

void setup(void)
{
	char *cur_dir = NULL;

	tst_require_root(NULL);

	tst_sig(FORK, DEF_HANDLER, cleanup);

	TEST_PAUSE;

	tst_tmpdir();

	if ((cur_dir = getcwd(cur_dir, 0)) == NULL)
		tst_brkm(TBROK | TERRNO, cleanup, "getcwd failed");

	sprintf(good_dir, "%s.%d", cur_dir, getpid());

	ltpuser1 = my_getpwnam(user1name);
}

void cleanup(void)
{
	tst_rmdir();
}