9fa5f6b4b9
implemented properly for a number of kernel subsystems. In general, they try to exercise the privilege first as the root user, then as a test user, in order to determine when privilege is being checked. Currently, these tests do not compare inside/outside jail, and probably should be enhanced to do that. Sponsored by: nCircle Network Security, Inc. Obtained from: TrustedBSD Project
136 lines
3.4 KiB
C
136 lines
3.4 KiB
C
/*-
|
|
* Copyright (c) 2006 nCircle Network Security, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This software was developed by Robert N. M. Watson for the TrustedBSD
|
|
* Project under contract to nCircle Network Security, Inc.
|
|
*
|
|
* 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, NCIRCLE NETWORK SECURITY,
|
|
* INC., 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.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
/*
|
|
* Test privilege check on /dev/io. By default, the permissions also protect
|
|
* against non-superuser access, so this program will modify permissions on
|
|
* /dev/io to allow group access for the wheel group, and revert the change
|
|
* on exit. This is not good for run-time security, but is necessary to test
|
|
* the checks properly.
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
|
|
#include <err.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
|
|
#include "main.h"
|
|
|
|
#define NEW_PERMS 0660
|
|
#define DEV_IO "/dev/io"
|
|
#define EXPECTED_PERMS 0600
|
|
|
|
static mode_t saved_perms;
|
|
|
|
static void
|
|
save_perms(void)
|
|
{
|
|
struct stat sb;
|
|
|
|
if (stat(DEV_IO, &sb) < 0)
|
|
err(-1, "save_perms: stat(%s)", DEV_IO);
|
|
|
|
saved_perms = sb.st_mode & ALLPERMS;
|
|
|
|
if (saved_perms != EXPECTED_PERMS)
|
|
err(-1, "save_perms: perms = 0%o; expected 0%o", saved_perms,
|
|
EXPECTED_PERMS);
|
|
|
|
}
|
|
|
|
static void
|
|
set_perms(void)
|
|
{
|
|
|
|
if (chmod(DEV_IO, NEW_PERMS) < 0)
|
|
err(-1, "set_perms: chmod(%s, 0%o)", DEV_IO, NEW_PERMS);
|
|
}
|
|
|
|
static void
|
|
restore_perms(void)
|
|
{
|
|
|
|
if (chmod(DEV_IO, saved_perms) < 0)
|
|
err(-1, "restore_perms: chmod(%s, 0%o)", DEV_IO, saved_perms);
|
|
}
|
|
|
|
static void
|
|
try_open(const char *test_case, uid_t uid, int expected)
|
|
{
|
|
int fd;
|
|
|
|
set_euid(uid);
|
|
fd = open(DEV_IO, O_RDONLY);
|
|
if (expected == 0) {
|
|
if (fd == -1) {
|
|
warn("try_open: %s open(%s) errno %d", DEV_IO,
|
|
test_case, errno);
|
|
goto out;
|
|
}
|
|
close(fd);
|
|
goto out;
|
|
}
|
|
if (fd >= 0) {
|
|
warn("try_open: %s open(%s) unexpected success", test_case,
|
|
DEV_IO);
|
|
close(fd);
|
|
goto out;
|
|
}
|
|
if (errno == expected)
|
|
goto out;
|
|
warn("try_open: %s open(%s) wrong errno %d, expected %d", DEV_IO,
|
|
test_case, errno, expected);
|
|
out:
|
|
set_euid(UID_ROOT);
|
|
}
|
|
|
|
void
|
|
priv_io(void)
|
|
{
|
|
|
|
assert_root();
|
|
|
|
save_perms();
|
|
|
|
try_open("root:0600", UID_ROOT, 0);
|
|
try_open("other", UID_OTHER, EACCES);
|
|
|
|
set_perms();
|
|
|
|
try_open("root:0660", UID_ROOT, 0);
|
|
try_open("other", UID_OTHER, EPERM);
|
|
|
|
restore_perms();
|
|
}
|