xref: /openbsd/lib/libc/net/inet_network.c (revision fb6201af)

/*	$OpenBSD: inet_network.c,v 1.13 2015/10/22 23:55:51 mmcc Exp $ */
/*
 * Copyright (c) 1983, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <ctype.h>

/*
 * Internet network address interpretation routine.
 * The library routines call this routine to interpret
 * network numbers.
 */
in_addr_t
inet_network(const char *cp)
{
	in_addr_t val, base, n;
	u_char c;
	in_addr_t parts[4], *pp = parts;
	int i;

again:
	val = 0; base = 10;
	if (*cp == '0')
		base = 8, cp++;
	if (*cp == 'x' || *cp == 'X')
		base = 16, cp++;
	while ((c = *cp)) {
		if (isdigit(c)) {
			val = (val * base) + (c - '0');
			cp++;
			continue;
		}
		if (base == 16 && isxdigit(c)) {
			val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
			cp++;
			continue;
		}
		break;
	}
	if (*cp == '.') {
		if (pp >= parts + 3)
			return (INADDR_NONE);
		*pp++ = val, cp++;
		goto again;
	}
	if (*cp && !isspace((unsigned char)*cp))
		return (INADDR_NONE);
	*pp++ = val;
	n = pp - parts;
	for (val = 0, i = 0; i < 4; i++) {
		val <<= 8;
		if (i < n)
			val |= parts[i] & 0xff;
	}
	return (val);
}
DEF_WEAK(inet_network);