/contrib/bind9/lib/isc/inet_aton.c

  1/*
  2 * Portions Copyright (C) 2004, 2005, 2007, 2008  Internet Systems Consortium, Inc. ("ISC")
  3 * Portions Copyright (C) 1996-2001  Internet Software Consortium.
  4 *
  5 * Permission to use, copy, modify, and/or distribute this software for any
  6 * purpose with or without fee is hereby granted, provided that the above
  7 * copyright notice and this permission notice appear in all copies.
  8 *
  9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 15 * PERFORMANCE OF THIS SOFTWARE.
 16 */
 17
 18/*
 19 * Copyright (c) 1983, 1990, 1993
 20 *    The Regents of the University of California.  All rights reserved.
 21 *
 22 * Redistribution and use in source and binary forms, with or without
 23 * modification, are permitted provided that the following conditions
 24 * are met:
 25 * 1. Redistributions of source code must retain the above copyright
 26 *    notice, this list of conditions and the following disclaimer.
 27 * 2. Redistributions in binary form must reproduce the above copyright
 28 *    notice, this list of conditions and the following disclaimer in the
 29 *    documentation and/or other materials provided with the distribution.
 30 * 3. All advertising materials mentioning features or use of this software
 31 *    must display the following acknowledgement:
 32 * 	This product includes software developed by the University of
 33 * 	California, Berkeley and its contributors.
 34 * 4. Neither the name of the University nor the names of its contributors
 35 *    may be used to endorse or promote products derived from this software
 36 *    without specific prior written permission.
 37 *
 38 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 39 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 41 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 42 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 43 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 44 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 45 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 46 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 47 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 48 * SUCH DAMAGE.
 49 */
 50
 51/*
 52 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 53 *
 54 * Permission to use, copy, modify, and distribute this software for any
 55 * purpose with or without fee is hereby granted, provided that the above
 56 * copyright notice and this permission notice appear in all copies, and that
 57 * the name of Digital Equipment Corporation not be used in advertising or
 58 * publicity pertaining to distribution of the document or software without
 59 * specific, written prior permission.
 60 *
 61 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 62 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 63 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 64 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 65 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 66 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 67 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 68 * SOFTWARE.
 69 */
 70/*! \file */
 71
 72#if defined(LIBC_SCCS) && !defined(lint)
 73static char sccsid[] = "@(#)inet_addr.c	8.1 (Berkeley) 6/17/93";
 74static char rcsid[] = "$Id: inet_aton.c,v 1.23 2008/12/01 23:47:45 tbox Exp $";
 75#endif /* LIBC_SCCS and not lint */
 76
 77#include <config.h>
 78
 79#include <ctype.h>
 80#include <stddef.h>		/* Required for NULL. */
 81
 82#include <isc/types.h>
 83#include <isc/net.h>
 84
 85/*%
 86 * Check whether "cp" is a valid ascii representation
 87 * of an Internet address and convert to a binary address.
 88 * Returns 1 if the address is valid, 0 if not.
 89 * This replaces inet_addr, the return value from which
 90 * cannot distinguish between failure and a local broadcast address.
 91 */
 92int
 93isc_net_aton(const char *cp, struct in_addr *addr) {
 94	unsigned long val;
 95	int base, n;
 96	unsigned char c;
 97	isc_uint8_t parts[4];
 98	isc_uint8_t *pp = parts;
 99	int digit;
100
101	c = *cp;
102	for (;;) {
103		/*
104		 * Collect number up to ``.''.
105		 * Values are specified as for C:
106		 * 0x=hex, 0=octal, isdigit=decimal.
107		 */
108		if (!isdigit(c & 0xff))
109			return (0);
110		val = 0; base = 10; digit = 0;
111		if (c == '0') {
112			c = *++cp;
113			if (c == 'x' || c == 'X')
114				base = 16, c = *++cp;
115			else {
116				base = 8;
117				digit = 1;
118			}
119		}
120		for (;;) {
121			/*
122			 * isascii() is valid for all integer values, and
123			 * when it is true, c is known to be in scope
124			 * for isdigit().  No cast necessary.  Similar
125			 * comment applies for later ctype uses.
126			 */
127			if (isascii(c) && isdigit(c)) {
128				if (base == 8 && (c == '8' || c == '9'))
129					return (0);
130				val = (val * base) + (c - '0');
131				c = *++cp;
132				digit = 1;
133			} else if (base == 16 && isascii(c) && isxdigit(c)) {
134				val = (val << 4) |
135					(c + 10 - (islower(c) ? 'a' : 'A'));
136				c = *++cp;
137				digit = 1;
138			} else
139				break;
140		}
141		if (c == '.') {
142			/*
143			 * Internet format:
144			 *	a.b.c.d
145			 *	a.b.c	(with c treated as 16 bits)
146			 *	a.b	(with b treated as 24 bits)
147			 */
148			if (pp >= parts + 3 || val > 0xffU)
149				return (0);
150			*pp++ = (isc_uint8_t)val;
151			c = *++cp;
152		} else
153			break;
154	}
155	/*
156	 * Check for trailing characters.
157	 */
158	if (c != '\0' && (!isascii(c) || !isspace(c)))
159		return (0);
160	/*
161	 * Did we get a valid digit?
162	 */
163	if (!digit)
164		return (0);
165	/*
166	 * Concoct the address according to
167	 * the number of parts specified.
168	 */
169	n = pp - parts + 1;
170	switch (n) {
171	case 1:				/* a -- 32 bits */
172		break;
173
174	case 2:				/* a.b -- 8.24 bits */
175		if (val > 0xffffffU)
176			return (0);
177		val |= parts[0] << 24;
178		break;
179
180	case 3:				/* a.b.c -- 8.8.16 bits */
181		if (val > 0xffffU)
182			return (0);
183		val |= (parts[0] << 24) | (parts[1] << 16);
184		break;
185
186	case 4:				/* a.b.c.d -- 8.8.8.8 bits */
187		if (val > 0xffU)
188			return (0);
189		val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
190		break;
191	}
192	if (addr != NULL)
193		addr->s_addr = htonl(val);
194
195	return (1);
196}