glibc/resolv/inet_net_pton.c

199 lines
5.2 KiB
C

/*
* Copyright (c) 1996,1999 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/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif
static int inet_net_pton_ipv4 (const char *src, u_char *dst,
size_t size) __THROW;
/*
* static int
* inet_net_pton(af, src, dst, size)
* convert network number from presentation to network format.
* accepts hex octets, hex strings, decimal octets, and /CIDR.
* "size" is in bytes and describes "dst".
* return:
* number of bits, either imputed classfully or specified with /CIDR,
* or -1 if some failure occurred (check errno). ENOENT means it was
* not a valid network specification.
* author:
* Paul Vixie (ISC), June 1996
*/
int
inet_net_pton (int af, const char *src, void *dst, size_t size)
{
switch (af) {
case AF_INET:
return (inet_net_pton_ipv4(src, dst, size));
default:
__set_errno (EAFNOSUPPORT);
return (-1);
}
}
/*
* static int
* inet_net_pton_ipv4(src, dst, size)
* convert IPv4 network number from presentation to network format.
* accepts hex octets, hex strings, decimal octets, and /CIDR.
* "size" is in bytes and describes "dst".
* return:
* number of bits, either imputed classfully or specified with /CIDR,
* or -1 if some failure occurred (check errno). ENOENT means it was
* not an IPv4 network specification.
* note:
* network byte order assumed. this means 192.5.5.240/28 has
* 0b11110000 in its fourth octet.
* author:
* Paul Vixie (ISC), June 1996
*/
static int
inet_net_pton_ipv4 (const char *src, u_char *dst, size_t size)
{
static const char xdigits[] = "0123456789abcdef";
int n, ch, tmp, dirty, bits;
const u_char *odst = dst;
ch = *src++;
if (ch == '0' && (src[0] == 'x' || src[0] == 'X')
&& isascii(src[1]) && isxdigit(src[1])) {
/* Hexadecimal: Eat nybble string. */
if (size <= 0)
goto emsgsize;
dirty = 0;
tmp = 0; /* To calm down gcc. */
src++; /* skip x or X. */
while (isxdigit((ch = *src++))) {
ch = _tolower(ch);
n = (const char *) __rawmemchr(xdigits, ch) - xdigits;
assert(n >= 0 && n <= 15);
if (dirty == 0)
tmp = n;
else
tmp = (tmp << 4) | n;
if (++dirty == 2) {
if (size-- <= 0)
goto emsgsize;
*dst++ = (u_char) tmp;
dirty = 0;
}
}
if (dirty) { /* Odd trailing nybble? */
if (size-- <= 0)
goto emsgsize;
*dst++ = (u_char) (tmp << 4);
}
} else if (isascii(ch) && isdigit(ch)) {
/* Decimal: eat dotted digit string. */
for (;;) {
tmp = 0;
do {
n = ((const char *) __rawmemchr(xdigits, ch)
- xdigits);
assert(n >= 0 && n <= 9);
tmp *= 10;
tmp += n;
if (tmp > 255)
goto enoent;
} while (isascii((ch = *src++)) && isdigit(ch));
if (size-- <= 0)
goto emsgsize;
*dst++ = (u_char) tmp;
if (ch == '\0' || ch == '/')
break;
if (ch != '.')
goto enoent;
ch = *src++;
if (!isascii(ch) || !isdigit(ch))
goto enoent;
}
} else
goto enoent;
bits = -1;
if (ch == '/' && isascii(src[0]) && isdigit(src[0]) && dst > odst) {
/* CIDR width specifier. Nothing can follow it. */
ch = *src++; /* Skip over the /. */
bits = 0;
do {
n = (const char *) __rawmemchr(xdigits, ch) - xdigits;
assert(n >= 0 && n <= 9);
bits *= 10;
bits += n;
} while (isascii((ch = *src++)) && isdigit(ch));
if (ch != '\0')
goto enoent;
if (bits > 32)
goto emsgsize;
}
/* Firey death and destruction unless we prefetched EOS. */
if (ch != '\0')
goto enoent;
/* If nothing was written to the destination, we found no address. */
if (dst == odst)
goto enoent;
/* If no CIDR spec was given, infer width from net class. */
if (bits == -1) {
if (*odst >= 240) /* Class E */
bits = 32;
else if (*odst >= 224) /* Class D */
bits = 4;
else if (*odst >= 192) /* Class C */
bits = 24;
else if (*odst >= 128) /* Class B */
bits = 16;
else /* Class A */
bits = 8;
/* If imputed mask is narrower than specified octets, widen. */
if (bits >= 8 && bits < ((dst - odst) * 8))
bits = (dst - odst) * 8;
}
/* Extend network to cover the actual mask. */
while (bits > ((dst - odst) * 8)) {
if (size-- <= 0)
goto emsgsize;
*dst++ = '\0';
}
return (bits);
enoent:
__set_errno (ENOENT);
return (-1);
emsgsize:
__set_errno (EMSGSIZE);
return (-1);
}