ipfw table add problem

[Michael Butler]

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On 11/25/13 19:39, Mark Andrews wrote:

>> When inet_pton() implementations have been rejecting leading zero's since
>> they were first written their can't be a POLA.  There can be a difference
>> but not a POLA.  To make is now accept a leading zero would be a POLA as
>> there is code that depends on leading zeros being rejected by it.

History disagrees with you; from the BIND 4 sources:

/* This is from the BIND 4.9.4 release, modified to compile by itself */

/* Copyright (c) 1996 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
OF THIS
 * SOFTWARE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char rcsid[] = "$Id: inet_pton.c,v 8.6 1996/06/26 23:17:26 vixie
Exp $";
#endif /* LIBC_SCCS and not lint */

 [ .. snip .. ]

/* int
 * inet_pton4(src, dst)
 *	like inet_aton() but without all the hexadecimal and shorthand.
 * return:
 *	1 if `src' is a valid dotted quad, else 0.
 * notice:
 *	does not touch `dst' unless it's returning 1.
 * author:
 *	Paul Vixie, 1996.
 */
static int
inet_pton4(src, dst)
	const char *src;
	u_char *dst;
{
	static const char digits[] = "0123456789";
	int saw_digit, octets, ch;
	u_char tmp[INADDRSZ], *tp;

	saw_digit = 0;
	octets = 0;
	*(tp = tmp) = 0;
	while ((ch = *src++) != '\0') {
		const char *pch;

		if ((pch = strchr(digits, ch)) != NULL) {
			u_int new = *tp * 10 + (pch - digits);

			if (new > 255)
				return (0);
			*tp = new;
			if (! saw_digit) {
				if (++octets > 4)
					return (0);
				saw_digit = 1;
			}
		} else if (ch == '.' && saw_digit) {
			if (octets == 4)
				return (0);
			*++tp = 0;
			saw_digit = 0;
		} else
			return (0);
	}
	if (octets < 4)
		return (0);
	/* bcopy(tmp, dst, INADDRSZ); */
	memcpy(dst, tmp, INADDRSZ);
	return (1);
}

Note especially that at some time after 1996, an additional two lines
were added and the man page not updated to reflect their addition.

Above the test "(new > 255)" these lines were added:

                        if (saw_digit && *tp == 0)
                                return (0);

 .. and which now causes this confusion.

Either the code or the man page are wrong,

	imb
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