NetBSD/lib/libc/net/rthdr.c

463 lines
10 KiB
C

/* $NetBSD: rthdr.c,v 1.16 2006/05/05 00:03:21 rpaulo Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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. Neither the name of the project 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 PROJECT 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 PROJECT 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>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: rthdr.c,v 1.16 2006/05/05 00:03:21 rpaulo Exp $");
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <assert.h>
#include <string.h>
#include <stdio.h>
#ifdef __weak_alias
__weak_alias(inet6_rthdr_add,_inet6_rthdr_add)
__weak_alias(inet6_rthdr_getaddr,_inet6_rthdr_getaddr)
__weak_alias(inet6_rthdr_getflags,_inet6_rthdr_getflags)
__weak_alias(inet6_rthdr_init,_inet6_rthdr_init)
__weak_alias(inet6_rthdr_lasthop,_inet6_rthdr_lasthop)
__weak_alias(inet6_rthdr_segments,_inet6_rthdr_segments)
__weak_alias(inet6_rthdr_space,_inet6_rthdr_space)
__weak_alias(inet6_rth_space, _inet6_rth_space)
__weak_alias(inet6_rth_init, _inet6_rth_init)
__weak_alias(inet6_rth_add, _inet6_rth_add)
__weak_alias(inet6_rth_reverse, _inet6_rth_reverse)
__weak_alias(inet6_rth_segments, _inet6_rth_segments)
__weak_alias(inet6_rth_getaddr, _inet6_rth_getaddr)
#endif
/*
* RFC2292 API
*/
size_t
inet6_rthdr_space(type, seg)
int type, seg;
{
switch (type) {
case IPV6_RTHDR_TYPE_0:
if (seg < 1 || seg > 23)
return (0);
return (CMSG_SPACE(sizeof(struct in6_addr) * seg +
sizeof(struct ip6_rthdr0)));
default:
return (0);
}
}
struct cmsghdr *
inet6_rthdr_init(bp, type)
void *bp;
int type;
{
struct cmsghdr *ch;
struct ip6_rthdr *rthdr;
_DIAGASSERT(bp != NULL);
ch = (struct cmsghdr *)bp;
rthdr = (struct ip6_rthdr *)(void *)CMSG_DATA(ch);
ch->cmsg_level = IPPROTO_IPV6;
ch->cmsg_type = IPV6_RTHDR;
switch (type) {
case IPV6_RTHDR_TYPE_0:
#ifdef COMPAT_RFC2292
ch->cmsg_len = CMSG_LEN(sizeof(struct ip6_rthdr0) -
sizeof(struct in6_addr));
#else
ch->cmsg_len = CMSG_LEN(sizeof(struct ip6_rthdr0));
#endif
(void)memset(rthdr, 0, sizeof(struct ip6_rthdr0));
rthdr->ip6r_type = IPV6_RTHDR_TYPE_0;
return (ch);
default:
return (NULL);
}
}
int
inet6_rthdr_add(cmsg, addr, flags)
struct cmsghdr *cmsg;
const struct in6_addr *addr;
u_int flags;
{
struct ip6_rthdr *rthdr;
_DIAGASSERT(cmsg != NULL);
_DIAGASSERT(addr != NULL);
rthdr = (struct ip6_rthdr *)(void *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)(void *)rthdr;
if (flags != IPV6_RTHDR_LOOSE && flags != IPV6_RTHDR_STRICT)
return (-1);
if (rt0->ip6r0_segleft == 23)
return (-1);
if (flags != IPV6_RTHDR_LOOSE)
return (-1);
rt0->ip6r0_segleft++;
(void)memcpy(((caddr_t)(void *)rt0) +
((rt0->ip6r0_len + 1) << 3), addr, sizeof(struct in6_addr));
rt0->ip6r0_len += sizeof(struct in6_addr) >> 3;
cmsg->cmsg_len = CMSG_LEN((rt0->ip6r0_len + 1) << 3);
break;
}
default:
return (-1);
}
return (0);
}
int
inet6_rthdr_lasthop(cmsg, flags)
struct cmsghdr *cmsg;
unsigned int flags;
{
struct ip6_rthdr *rthdr;
_DIAGASSERT(cmsg != NULL);
rthdr = (struct ip6_rthdr *)(void *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)(void *)rthdr;
if (rt0->ip6r0_segleft > 23)
return (-1);
if (flags != IPV6_RTHDR_LOOSE)
return (-1);
break;
}
default:
return (-1);
}
return (0);
}
#if 0
int
inet6_rthdr_reverse(in, out)
const struct cmsghdr *in;
struct cmsghdr *out;
{
return (-1);
}
#endif
int
inet6_rthdr_segments(cmsg)
const struct cmsghdr *cmsg;
{
const struct ip6_rthdr *rthdr;
_DIAGASSERT(cmsg != NULL);
rthdr = __UNCONST(CCMSG_DATA(cmsg));
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
const struct ip6_rthdr0 *rt0 =
(const struct ip6_rthdr0 *)(const void *)rthdr;
if (rt0->ip6r0_len % 2 || 46 < rt0->ip6r0_len)
return (-1);
return (rt0->ip6r0_len * 8) / sizeof(struct in6_addr);
}
default:
return (-1);
}
}
struct in6_addr *
inet6_rthdr_getaddr(cmsg, idx)
struct cmsghdr *cmsg;
int idx;
{
struct ip6_rthdr *rthdr;
_DIAGASSERT(cmsg != NULL);
rthdr = (struct ip6_rthdr *)(void *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)(void *)rthdr;
int naddr;
if (rt0->ip6r0_len % 2 || 46 < rt0->ip6r0_len)
return NULL;
naddr = (rt0->ip6r0_len * 8) / sizeof(struct in6_addr);
if (idx <= 0 || naddr < idx)
return NULL;
#ifdef COMPAT_RFC2292
return ((struct in6_addr *)(void *)(rt0 + 1)) + idx - 1;
#else
return ((struct in6_addr *)(void *)(rt0 + 1)) + idx;
#endif
}
default:
return NULL;
}
}
int
inet6_rthdr_getflags(cmsg, idx)
const struct cmsghdr *cmsg;
int idx;
{
const struct ip6_rthdr *rthdr;
_DIAGASSERT(cmsg != NULL);
rthdr = __UNCONST(CCMSG_DATA(cmsg));
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
const struct ip6_rthdr0 *rt0 = (const struct ip6_rthdr0 *)
(const void *)rthdr;
int naddr;
if (rt0->ip6r0_len % 2 || 46 < rt0->ip6r0_len)
return (-1);
naddr = (rt0->ip6r0_len * 8) / sizeof(struct in6_addr);
if (idx < 0 || naddr < idx)
return (-1);
return IPV6_RTHDR_LOOSE;
}
default:
return (-1);
}
}
/*
* RFC3542 (2292bis) API
*/
socklen_t
inet6_rth_space(int type, int segments)
{
switch (type) {
case IPV6_RTHDR_TYPE_0:
return (((segments * 2) + 1) << 3);
default:
return (0); /* type not suppported */
}
}
void *
inet6_rth_init(void *bp, socklen_t bp_len, int type, int segments)
{
struct ip6_rthdr *rth;
struct ip6_rthdr0 *rth0;
_DIAGASSERT(bp != NULL);
rth = (struct ip6_rthdr *)bp;
switch (type) {
case IPV6_RTHDR_TYPE_0:
/* length validation */
if (bp_len < inet6_rth_space(IPV6_RTHDR_TYPE_0, segments))
return (NULL);
memset(bp, 0, bp_len);
rth0 = (struct ip6_rthdr0 *)(void *)rth;
rth0->ip6r0_len = segments * 2;
rth0->ip6r0_type = IPV6_RTHDR_TYPE_0;
rth0->ip6r0_segleft = 0;
rth0->ip6r0_reserved = 0;
break;
default:
return (NULL); /* type not supported */
}
return (bp);
}
int
inet6_rth_add(void *bp, const struct in6_addr *addr)
{
struct ip6_rthdr *rth;
struct ip6_rthdr0 *rth0;
struct in6_addr *nextaddr;
_DIAGASSERT(bp != NULL);
rth = (struct ip6_rthdr *)bp;
switch (rth->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rth0 = (struct ip6_rthdr0 *)(void *)rth;
nextaddr = (struct in6_addr *)(void *)(rth0 + 1)
+ rth0->ip6r0_segleft;
*nextaddr = *addr;
rth0->ip6r0_segleft++;
break;
default:
return (-1); /* type not supported */
}
return (0);
}
int
inet6_rth_reverse(const void *in, void *out)
{
const struct ip6_rthdr *rth_in;
const struct ip6_rthdr0 *rth0_in;
struct ip6_rthdr0 *rth0_out;
int i, segments;
_DIAGASSERT(in != NULL);
_DIAGASSERT(out != NULL);
rth_in = (const struct ip6_rthdr *)in;
switch (rth_in->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rth0_in = (const struct ip6_rthdr0 *)in;
rth0_out = (struct ip6_rthdr0 *)out;
/* parameter validation XXX too paranoid? */
if (rth0_in->ip6r0_len % 2)
return (-1);
segments = rth0_in->ip6r0_len / 2;
/* we can't use memcpy here, since in and out may overlap */
memmove((void *)rth0_out, (const void *)rth0_in,
(unsigned int)(((rth0_in->ip6r0_len) + 1) << 3));
rth0_out->ip6r0_segleft = segments;
/* reverse the addresses */
for (i = 0; i < segments / 2; i++) {
struct in6_addr addr_tmp, *addr1, *addr2;
addr1 = (struct in6_addr *)(void *)(rth0_out + 1) + i;
addr2 = (struct in6_addr *)(void *)(rth0_out + 1) +
(segments - i - 1);
addr_tmp = *addr1;
*addr1 = *addr2;
*addr2 = addr_tmp;
}
break;
default:
return (-1); /* type not supported */
}
return (0);
}
int
inet6_rth_segments(const void *bp)
{
const struct ip6_rthdr *rh;
const struct ip6_rthdr0 *rh0;
unsigned int addrs;
_DIAGASSERT(bp != NULL);
rh = (const struct ip6_rthdr *)bp;
switch (rh->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rh0 = (const struct ip6_rthdr0 *)bp;
/*
* Validation for a type-0 routing header.
* Is this too strict?
*/
if ((rh0->ip6r0_len % 2) != 0 ||
(addrs = (rh0->ip6r0_len / 2)) < rh0->ip6r0_segleft)
return (-1);
return (addrs);
default:
return (-1); /* unknown type */
}
}
struct in6_addr *
inet6_rth_getaddr(const void *bp, int idx)
{
const struct ip6_rthdr *rh;
const struct ip6_rthdr0 *rh0;
unsigned int addrs;
_DIAGASSERT(bp != NULL);
rh = (const struct ip6_rthdr *)bp;
switch (rh->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rh0 = (const struct ip6_rthdr0 *)bp;
/*
* Validation for a type-0 routing header.
* Is this too strict?
*/
if ((rh0->ip6r0_len % 2) != 0 ||
(addrs = (rh0->ip6r0_len / 2)) < rh0->ip6r0_segleft)
return (NULL);
if (idx < 0 || addrs <= idx)
return (NULL);
return (((struct in6_addr *)(void *)__UNCONST(rh0 + 1)) + idx);
default:
return (NULL); /* unknown type */
}
}