inet_aton.c revision ec5347e2c775f027573ce5648b910361aa926c01
/*
* Portions Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC")
* Portions Copyright (C) 1996-2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or 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 ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC 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.
*/
/*
* Copyright (c) 1983, 1990, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
/*
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
*
* 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, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* CORPORATION 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.
*/
/*! \file */
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)inet_addr.c 8.1 (Berkeley) 6/17/93";
static char rcsid[] = "$Id: inet_aton.c,v 1.20 2007/06/18 23:47:44 tbox Exp $";
#endif /* LIBC_SCCS and not lint */
#include <config.h>
#include <ctype.h>
#include <stddef.h> /* Required for NULL. */
#include <isc/types.h>
#include <isc/net.h>
/*%
* Check whether "cp" is a valid ascii representation
* of an Internet address and convert to a binary address.
* Returns 1 if the address is valid, 0 if not.
* This replaces inet_addr, the return value from which
* cannot distinguish between failure and a local broadcast address.
*/
int
isc_net_aton(const char *cp, struct in_addr *addr) {
unsigned long val;
int base, n;
unsigned char c;
isc_uint8_t parts[4];
isc_uint8_t *pp = parts;
int digit;
c = *cp;
for (;;) {
/*
* Collect number up to ``.''.
* Values are specified as for C:
* 0x=hex, 0=octal, isdigit=decimal.
*/
if (!isdigit(c & 0xff))
return (0);
val = 0; base = 10; digit = 0;
if (c == '0') {
c = *++cp;
if (c == 'x' || c == 'X')
base = 16, c = *++cp;
else {
base = 8;
digit = 1;
}
}
for (;;) {
/*
* isascii() is valid for all integer values, and
* when it is true, c is known to be in scope
* for isdigit(). No cast necessary. Similar
* comment applies for later ctype uses.
*/
if (isascii(c) && isdigit(c)) {
if (base == 8 && (c == '8' || c == '9'))
return (0);
val = (val * base) + (c - '0');
c = *++cp;
digit = 1;
} else if (base == 16 && isascii(c) && isxdigit(c)) {
val = (val << 4) |
(c + 10 - (islower(c) ? 'a' : 'A'));
c = *++cp;
digit = 1;
} else
break;
}
if (c == '.') {
/*
* Internet format:
* a.b.c.d
* a.b.c (with c treated as 16 bits)
* a.b (with b treated as 24 bits)
*/
if (pp >= parts + 3 || val > 0xff)
return (0);
*pp++ = (isc_uint8_t)val;
c = *++cp;
} else
break;
}
/*
* Check for trailing characters.
*/
if (c != '\0' && (!isascii(c) || !isspace(c)))
return (0);
/*
* Did we get a valid digit?
*/
if (!digit)
return (0);
/*
* Concoct the address according to
* the number of parts specified.
*/
n = pp - parts + 1;
switch (n) {
case 1: /* a -- 32 bits */
break;
case 2: /* a.b -- 8.24 bits */
if (val > 0xffffff)
return (0);
val |= parts[0] << 24;
break;
case 3: /* a.b.c -- 8.8.16 bits */
if (val > 0xffff)
return (0);
val |= (parts[0] << 24) | (parts[1] << 16);
break;
case 4: /* a.b.c.d -- 8.8.8.8 bits */
if (val > 0xff)
return (0);
val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
break;
}
if (addr != NULL)
addr->s_addr = htonl(val);
return (1);
}