freebsd-dev/lib/libc/net/rthdr.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

437 lines
9.7 KiB
C

/* $KAME: rthdr.c,v 1.19 2003/06/06 10:48:51 itojun Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <string.h>
#include <stdio.h>
/*
* RFC2292 API
*/
size_t
inet6_rthdr_space(int type, int seg)
{
switch (type) {
case IPV6_RTHDR_TYPE_0:
if (seg < 1 || seg > 23)
return (0);
#ifdef COMPAT_RFC2292
return (CMSG_SPACE(sizeof(struct in6_addr) * (seg - 1) +
sizeof(struct ip6_rthdr0)));
#else
return (CMSG_SPACE(sizeof(struct in6_addr) * seg +
sizeof(struct ip6_rthdr0)));
#endif
default:
return (0);
}
}
struct cmsghdr *
inet6_rthdr_init(void *bp, int type)
{
struct cmsghdr *ch = (struct cmsghdr *)bp;
struct ip6_rthdr *rthdr;
rthdr = (struct ip6_rthdr *)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
bzero(rthdr, sizeof(struct ip6_rthdr0));
rthdr->ip6r_type = IPV6_RTHDR_TYPE_0;
return (ch);
default:
return (NULL);
}
}
/* ARGSUSED */
int
inet6_rthdr_add(struct cmsghdr *cmsg, const struct in6_addr *addr, u_int flags)
{
struct ip6_rthdr *rthdr;
rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
if (flags != IPV6_RTHDR_LOOSE && flags != IPV6_RTHDR_STRICT)
return (-1);
if (rt0->ip6r0_segleft == 23)
return (-1);
#ifdef COMPAT_RFC1883 /* XXX */
if (flags == IPV6_RTHDR_STRICT) {
int c, b;
c = rt0->ip6r0_segleft / 8;
b = rt0->ip6r0_segleft % 8;
rt0->ip6r0_slmap[c] |= (1 << (7 - b));
}
#else
if (flags != IPV6_RTHDR_LOOSE)
return (-1);
#endif
rt0->ip6r0_segleft++;
bcopy(addr, (caddr_t)rt0 + ((rt0->ip6r0_len + 1) << 3),
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);
}
/* ARGSUSED */
int
inet6_rthdr_lasthop(struct cmsghdr *cmsg, unsigned int flags)
{
struct ip6_rthdr *rthdr;
rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
#ifdef COMPAT_RFC1883 /* XXX */
if (flags != IPV6_RTHDR_LOOSE && flags != IPV6_RTHDR_STRICT)
return (-1);
#endif /* COMPAT_RFC1883 */
if (rt0->ip6r0_segleft > 23)
return (-1);
#ifdef COMPAT_RFC1883 /* XXX */
if (flags == IPV6_RTHDR_STRICT) {
int c, b;
c = rt0->ip6r0_segleft / 8;
b = rt0->ip6r0_segleft % 8;
rt0->ip6r0_slmap[c] |= (1 << (7 - b));
}
#else
if (flags != IPV6_RTHDR_LOOSE)
return (-1);
#endif /* COMPAT_RFC1883 */
break;
}
default:
return (-1);
}
return (0);
}
#if 0
int
inet6_rthdr_reverse(const struct cmsghdr *in, struct cmsghdr *out)
{
return (-1);
}
#endif
int
inet6_rthdr_segments(const struct cmsghdr *cmsg)
{
struct ip6_rthdr *rthdr;
rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)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(struct cmsghdr *cmsg, int idx)
{
struct ip6_rthdr *rthdr;
rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)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 *)(rt0 + 1)) + idx - 1);
#else
return (((struct in6_addr *)(rt0 + 1)) + idx);
#endif
}
default:
return NULL;
}
}
int
inet6_rthdr_getflags(const struct cmsghdr *cmsg, int idx)
{
struct ip6_rthdr *rthdr;
rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
switch (rthdr->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
{
struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)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);
#ifdef COMPAT_RFC1883 /* XXX */
if (rt0->ip6r0_slmap[idx / 8] & (0x80 >> (idx % 8)))
return IPV6_RTHDR_STRICT;
else
return IPV6_RTHDR_LOOSE;
#else
return IPV6_RTHDR_LOOSE;
#endif /* COMPAT_RFC1883 */
}
default:
return (-1);
}
}
/*
* RFC3542 API
*/
socklen_t
inet6_rth_space(int type, int segments)
{
switch (type) {
case IPV6_RTHDR_TYPE_0:
if ((segments >= 0) && (segments <= 127))
return (((segments * 2) + 1) << 3);
/* FALLTHROUGH */
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_rthdr *)bp;
struct ip6_rthdr0 *rth0;
switch (type) {
case IPV6_RTHDR_TYPE_0:
/* length validation */
if (bp_len < inet6_rth_space(IPV6_RTHDR_TYPE_0, segments))
return (NULL);
/* segment validation */
if ((segments < 0) || (segments > 127))
return (NULL);
memset(bp, 0, bp_len);
rth0 = (struct ip6_rthdr0 *)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_rthdr *)bp;
struct ip6_rthdr0 *rth0;
struct in6_addr *nextaddr;
switch (rth->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rth0 = (struct ip6_rthdr0 *)rth;
/* Don't exceed the number of stated segments */
if (rth0->ip6r0_segleft == (rth0->ip6r0_len / 2))
return (-1);
nextaddr = (struct in6_addr *)(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)
{
struct ip6_rthdr *rth_in = (struct ip6_rthdr *)in;
struct ip6_rthdr0 *rth0_in, *rth0_out;
int i, segments;
switch (rth_in->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rth0_in = (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, (void *)rth0_in,
((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 *)(rth0_out + 1) + i;
addr2 = (struct in6_addr *)(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)
{
struct ip6_rthdr *rh = (struct ip6_rthdr *)bp;
struct ip6_rthdr0 *rh0;
int addrs;
switch (rh->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rh0 = (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 >> 1)) < rh0->ip6r0_segleft)
return (-1);
return (addrs);
default:
return (-1); /* unknown type */
}
}
struct in6_addr *
inet6_rth_getaddr(const void *bp, int idx)
{
struct ip6_rthdr *rh = (struct ip6_rthdr *)bp;
struct ip6_rthdr0 *rh0;
int addrs;
switch (rh->ip6r_type) {
case IPV6_RTHDR_TYPE_0:
rh0 = (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 >> 1)) < rh0->ip6r0_segleft)
return (NULL);
if (idx < 0 || addrs <= idx)
return (NULL);
return (((struct in6_addr *)(rh0 + 1)) + idx);
default:
return (NULL); /* unknown type */
break;
}
}