/* * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") * 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 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. */#if defined(LIBC_SCCS) && !defined(lint)static const char rcsid[] = "$Id: inet_cidr_ntop.c,v 1.1.2.1.8.2 2004/03/17 00:29:46 marka Exp $";#endif#include "port_before.h"#include <sys/types.h>#include <sys/socket.h>#include <netinet/in.h>#include <arpa/nameser.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)#endifstatic char *	inet_cidr_ntop_ipv4 __P((const u_char *src, int bits,					 char *dst, size_t size));static char *	inet_cidr_ntop_ipv6 __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));	case AF_INET6:		return (inet_cidr_ntop_ipv6(src, bits, dst, size));	default:		errno = EAFNOSUPPORT;		return (NULL);	}}static intdecoct(const u_char *src, int bytes, char *dst, size_t size) {	char *odst = dst;	char *t;	int b;	for (b = 1; b <= bytes; b++) {		if (size < sizeof "255.")			return (0);		t = dst;		dst += SPRINTF((dst, "%u", *src++));		if (b != bytes) {			*dst++ = '.';			*dst = '\0';		}		size -= (size_t)(dst - t);	}	return (dst - odst);}/* * 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;	size_t len = 4;	size_t b;	size_t bytes;	if ((bits < -1) || (bits > 32)) {		errno = EINVAL;		return (NULL);	}	/* Find number of significant bytes in address. */	if (bits == -1)		len = 4;	else		for (len = 1, b = 1 ; b < 4U; b++)			if (*(src + b))				len = b + 1;	/* Format whole octets plus nonzero trailing octets. */	bytes = (((bits <= 0) ? 1 : bits) + 7) / 8;	if (len > bytes)		bytes = len;	b = decoct(src, bytes, dst, size);	if (b == 0U)		goto emsgsize;	dst += b;	size -= b;	if (bits != -1) {		/* Format CIDR /width. */		if (size < sizeof "/32")			goto emsgsize;		dst += SPRINTF((dst, "/%u", bits));	}	return (odst); emsgsize:	errno = EMSGSIZE;	return (NULL);} static char *inet_cidr_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size) {	/*	 * Note that int32_t and int16_t need only be "at least" large enough	 * to contain a value of the specified size.  On some systems, like	 * Crays, there is no such thing as an integer variable with 16 bits.	 * Keep this in mind if you think this function should have been coded	 * to use pointer overlays.  All the world's not a VAX.	 */	char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255/128"];	char *tp;	struct { int base, len; } best, cur;	u_int words[NS_IN6ADDRSZ / NS_INT16SZ];	int i;	if ((bits < -1) || (bits > 128)) {		errno = EINVAL;		return (NULL);	}	/*	 * Preprocess:	 *	Copy the input (bytewise) array into a wordwise array.	 *	Find the longest run of 0x00's in src[] for :: shorthanding.	 */	memset(words, '\0', sizeof words);	for (i = 0; i < NS_IN6ADDRSZ; i++)		words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));	best.base = -1;	cur.base = -1;	for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {		if (words[i] == 0) {			if (cur.base == -1)				cur.base = i, cur.len = 1;			else				cur.len++;		} else {			if (cur.base != -1) {				if (best.base == -1 || cur.len > best.len)					best = cur;				cur.base = -1;			}		}	}	if (cur.base != -1) {		if (best.base == -1 || cur.len > best.len)			best = cur;	}	if (best.base != -1 && best.len < 2)		best.base = -1;	/*	 * Format the result.	 */	tp = tmp;	for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {		/* Are we inside the best run of 0x00's? */		if (best.base != -1 && i >= best.base &&		    i < (best.base + best.len)) {			if (i == best.base)				*tp++ = ':';			continue;		}		/* Are we following an initial run of 0x00s or any real hex? */		if (i != 0)			*tp++ = ':';		/* Is this address an encapsulated IPv4? */		if (i == 6 && best.base == 0 && (best.len == 6 ||		    (best.len == 7 && words[7] != 0x0001) ||		    (best.len == 5 && words[5] == 0xffff))) {			int n;			if (src[15] || bits == -1 || bits > 120)				n = 4;			else if (src[14] || bits > 112)				n = 3;			else				n = 2;			n = decoct(src+12, n, tp, sizeof tmp - (tp - tmp));			if (n == 0) {				errno = EMSGSIZE;				return (NULL);			}			tp += strlen(tp);			break;		}		tp += SPRINTF((tp, "%x", words[i]));	}	/* Was it a trailing run of 0x00's? */	if (best.base != -1 && (best.base + best.len) == 	    (NS_IN6ADDRSZ / NS_INT16SZ))		*tp++ = ':';	*tp = '\0';	if (bits != -1)		tp += SPRINTF((tp, "/%u", bits));	/*	 * Check for overflow, copy, and we're done.	 */	if ((size_t)(tp - tmp) > size) {		errno = EMSGSIZE;		return (NULL);	}	strcpy(dst, tmp);	return (dst);}