/*	$OpenBSD: nsap_addr.c,v 1.6 2005/08/06 20:30:03 espie Exp $	*/

/*
 * 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.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <ctype.h>
#include <resolv.h>

static char
xtob(int c)
{
	return (c - (((c >= '0') && (c <= '9')) ? '0' : '7'));
}

u_int
inet_nsap_addr(const char *ascii, u_char *binary, int maxlen)
{
	u_char c, nib;
	u_int len = 0;

	while ((c = *ascii++) != '\0' && len < maxlen) {
		if (c == '.' || c == '+' || c == '/')
			continue;
		if (!isascii(c))
			return (0);
		if (islower(c))
			c = toupper(c);
		if (isxdigit(c)) {
			nib = xtob(c);
			if ((c = *ascii++)) {
				c = toupper(c);
				if (isxdigit(c)) {
					*binary++ = (nib << 4) | xtob(c);
					len++;
				} else
					return (0);
			}
			else
				return (0);
		}
		else
			return (0);
	}
	return (len);
}

char *
inet_nsap_ntoa(int binlen, const u_char *binary, char *ascii)
{
	int nib;
	int i;
	static char tmpbuf[255*3];
	char *start;

	if (ascii)
		start = ascii;
	else {
		ascii = tmpbuf;
		start = tmpbuf;
	}

	if (binlen > 255)
		binlen = 255;

	for (i = 0; i < binlen; i++) {
		nib = *binary >> 4;
		*ascii++ = nib + (nib < 10 ? '0' : '7');
		nib = *binary++ & 0x0f;
		*ascii++ = nib + (nib < 10 ? '0' : '7');
		if (((i % 2) == 0 && (i + 1) < binlen))
			*ascii++ = '.';
	}
	*ascii = '\0';
	return (start);
}