freebsd-dev/lib/libc/gen/check_utility_compat.c
Xin LI 53e075c0b9 - Reduce buffer size from LINE_MAX to PATH_MAX, there is no point to store
path longer than this.
 - Fix an unreached case of check against sizeof buf, which in turn leads
   to an off-by-one nul byte write on the stack.  The original condition
   can never be satisfied because the passed boundary is the maximum value
   that can be returned, so code was harmless.

MFC after:	1 month
2012-12-21 22:20:59 +00:00

72 lines
2.3 KiB
C

/*
* Copyright 2002 Massachusetts Institute of Technology
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that both the above copyright notice and this
* permission notice appear in all copies, that both the above
* copyright notice and this permission notice appear in all
* supporting documentation, and that the name of M.I.T. not be used
* in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission. M.I.T. makes
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
* SHALL M.I.T. 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("$FreeBSD$");
/*
* I din't use "namespace.h" here because none of the relevant utilities
* are threaded, so I'm not concerned about cancellation points or other
* niceties.
*/
#include <sys/limits.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define _PATH_UTIL_COMPAT "/etc/compat-FreeBSD-4-util"
#define _ENV_UTIL_COMPAT "_COMPAT_FreeBSD_4"
int
check_utility_compat(const char *utility)
{
char buf[PATH_MAX];
char *p, *bp;
int len;
if ((p = getenv(_ENV_UTIL_COMPAT)) != NULL) {
strlcpy(buf, p, sizeof buf);
} else {
if ((len = readlink(_PATH_UTIL_COMPAT, buf, sizeof(buf) - 1)) < 0)
return 0;
buf[len] = '\0';
}
if (buf[0] == '\0')
return 1;
bp = buf;
while ((p = strsep(&bp, ",")) != NULL) {
if (strcmp(p, utility) == 0)
return 1;
}
return 0;
}