NetBSD/dist/bind/lib/inet/inet_cidr_ntop.c

132 lines
3.4 KiB
C

/* $NetBSD: inet_cidr_ntop.c,v 1.1.1.1 1999/11/20 18:54:07 veego Exp $ */
/*
* Copyright (c) 1998,1999 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "Id: inet_cidr_ntop.c,v 8.4 1999/10/07 20:44:02 vixie Exp";
#endif
#include "port_before.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "port_after.h"
#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif
static char * inet_cidr_ntop_ipv4 __P((const u_char *src, int bits,
char *dst, size_t size));
/*
* char *
* inet_cidr_ntop(af, src, bits, dst, size)
* convert network address from network to presentation format.
* "src"'s size is determined from its "af".
* return:
* pointer to dst, or NULL if an error occurred (check errno).
* note:
* 192.5.5.1/28 has a nonzero host part, which means it isn't a network
* as called for by inet_net_ntop() but it can be a host address with
* an included netmask.
* author:
* Paul Vixie (ISC), October 1998
*/
char *
inet_cidr_ntop(int af, const void *src, int bits, char *dst, size_t size) {
switch (af) {
case AF_INET:
return (inet_cidr_ntop_ipv4(src, bits, dst, size));
default:
errno = EAFNOSUPPORT;
return (NULL);
}
}
/*
* static char *
* inet_cidr_ntop_ipv4(src, bits, dst, size)
* convert IPv4 network address from network to presentation format.
* "src"'s size is determined from its "af".
* return:
* pointer to dst, or NULL if an error occurred (check errno).
* note:
* network byte order assumed. this means 192.5.5.240/28 has
* 0b11110000 in its fourth octet.
* author:
* Paul Vixie (ISC), October 1998
*/
static char *
inet_cidr_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size) {
char *odst = dst;
char *t;
size_t len = 4;
int b, tb;
if ((bits < -1) || (bits > 32)) {
errno = EINVAL;
return (NULL);
}
/* Find number of significant bytes in address. */
if (bits == -1)
len = 3;
else
for (len = 0,b = 1 ; b < 4; b++)
if (*(src + b))
len = b;
/* Format whole octets plus nonzero trailing octets. */
tb = (bits <= 0) ? 1 : (bits - 1);
for (b = 0; b <= (tb / 8) || (b <= len); b++) {
if (size < sizeof "255.")
goto emsgsize;
t = dst;
dst += SPRINTF((dst, "%u", *src++));
if (b + 1 <= (tb / 8) || (b + 1 <= len)) {
*dst++ = '.';
*dst = '\0';
}
size -= (size_t)(dst - t);
}
if (bits != -1) {
/* Format CIDR /width. */
if (size < sizeof "/32")
goto emsgsize;
dst += SPRINTF((dst, "/%u", bits));
}
return (odst);
emsgsize:
errno = EMSGSIZE;
return (NULL);
}