/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2001 Charles Mott <cm@linktel.net>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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/cdefs.h>
#include <sys/param.h>
#include <sys/ctype.h>
#include <sys/limits.h>
#include <sys/systm.h>
#include <netinet/in.h>
int
inet_aton(const char *cp, struct in_addr *addr)
{
u_long parts[4];
in_addr_t val;
const char *c;
char *endptr;
int gotend, n;
c = (const char *)cp;
n = 0;
/*
* Run through the string, grabbing numbers until
* the end of the string, or some error
*/
gotend = 0;
while (!gotend) {
unsigned long l;
l = strtoul(c, &endptr, 0);
if (l == ULONG_MAX || (l == 0 && endptr == c))
return (0);
val = (in_addr_t)l;
/*
* If the whole string is invalid, endptr will equal
* c.. this way we can make sure someone hasn't
* gone '.12' or something which would get past
* the next check.
*/
if (endptr == c)
return (0);
parts[n] = val;
c = endptr;
/* Check the next character past the previous number's end */
switch (*c) {
case '.' :
/* Make sure we only do 3 dots .. */
if (n == 3) /* Whoops. Quit. */
return (0);
n++;
c++;
break;
case '\0':
gotend = 1;
break;
default:
if (isspace((unsigned char)*c)) {
gotend = 1;
break;
} else {
/* Invalid character, then fail. */
return (0);
}
}
}
/* Concoct the address according to the number of parts specified. */
switch (n) {
case 0: /* a -- 32 bits */
/*
* Nothing is necessary here. Overflow checking was
* already done in strtoul().
*/
break;
case 1: /* a.b -- 8.24 bits */
if (val > 0xffffff || parts[0] > 0xff)
return (0);
val |= parts[0] << 24;
break;
case 2: /* a.b.c -- 8.8.16 bits */
if (val > 0xffff || parts[0] > 0xff || parts[1] > 0xff)
return (0);
val |= (parts[0] << 24) | (parts[1] << 16);
break;
case 3: /* a.b.c.d -- 8.8.8.8 bits */
if (val > 0xff || parts[0] > 0xff || parts[1] > 0xff ||
parts[2] > 0xff)
return (0);
val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
break;
}
if (addr != NULL)
addr->s_addr = htonl(val);
return (1);
}
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