freebsd-skq/sys/netinet/in_gif.c
2000-03-11 22:11:57 +00:00

362 lines
8.5 KiB
C

/*
* 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.
*
* $FreeBSD$
*/
/*
* in_gif.c
*/
#include "opt_mrouting.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/protosw.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif
#include <netinet/ip_var.h>
#include <netinet/in_gif.h>
#include <netinet/ip_ecn.h>
#ifdef INET6
#include <netinet6/ip6_ecn.h>
#endif
#ifdef MROUTING
#include <netinet/ip_mroute.h>
#endif /* MROUTING */
#include <net/if_gif.h>
#include "gif.h"
#include <machine/stdarg.h>
#include <net/net_osdep.h>
#if NGIF > 0
int ip_gif_ttl = GIF_TTL;
#else
int ip_gif_ttl = 0;
#endif
SYSCTL_DECL(_net_inet_ip);
SYSCTL_INT(_net_inet_ip, IPCTL_GIF_TTL, gifttl, CTLFLAG_RW,
&ip_gif_ttl, 0, "");
#define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
#define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1]))
int
in_gif_output(ifp, family, m, rt)
struct ifnet *ifp;
int family;
struct mbuf *m;
struct rtentry *rt;
{
register struct gif_softc *sc = (struct gif_softc*)ifp;
struct sockaddr_in *dst = (struct sockaddr_in *)&sc->gif_ro.ro_dst;
struct sockaddr_in *sin_src = (struct sockaddr_in *)sc->gif_psrc;
struct sockaddr_in *sin_dst = (struct sockaddr_in *)sc->gif_pdst;
struct ip iphdr; /* capsule IP header, host byte ordered */
int proto, error;
u_int8_t tos;
#ifdef INET6
struct ip6_hdr *ip6 = NULL;
#endif
if (sin_src == NULL || sin_dst == NULL ||
sin_src->sin_family != AF_INET ||
sin_dst->sin_family != AF_INET) {
m_freem(m);
return EAFNOSUPPORT;
}
switch (family) {
case AF_INET:
{
struct ip *ip;
proto = IPPROTO_IPV4;
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (!m)
return ENOBUFS;
}
ip = mtod(m, struct ip *);
tos = ip->ip_tos;
break;
}
#ifdef INET6
case AF_INET6:
{
proto = IPPROTO_IPV6;
if (m->m_len < sizeof(*ip6)) {
m = m_pullup(m, sizeof(*ip6));
if (!m)
return ENOBUFS;
}
ip6 = mtod(m, struct ip6_hdr *);
tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
break;
}
#endif /*INET6*/
default:
#ifdef DIAGNOSTIC
printf("in_gif_output: warning: unknown family %d passed\n",
family);
#endif
m_freem(m);
return EAFNOSUPPORT;
}
bzero(&iphdr, sizeof(iphdr));
iphdr.ip_src = sin_src->sin_addr;
#ifdef INET6
/* XXX: temporal stf support hack */
if (bcmp(ifp->if_name, "stf", 3) == 0) {
if (ip6 == NULL) {
m_freem(m);
return ENETUNREACH;
}
if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst))
iphdr.ip_dst = *GET_V4(&ip6->ip6_dst);
else if (rt && rt->rt_gateway->sa_family == AF_INET6) {
struct in6_addr *dst6;
dst6 = &((struct sockaddr_in6 *)
(rt->rt_gateway))->sin6_addr;
if (IN6_IS_ADDR_6TO4(dst6))
iphdr.ip_dst = *GET_V4(dst6);
else {
m_freem(m);
return ENETUNREACH;
}
} else {
m_freem(m);
return ENETUNREACH;
}
} else
#endif
if (ifp->if_flags & IFF_LINK0) {
/* multi-destination mode */
if (sin_dst->sin_addr.s_addr != INADDR_ANY)
iphdr.ip_dst = sin_dst->sin_addr;
else if (rt) {
iphdr.ip_dst = ((struct sockaddr_in *)
(rt->rt_gateway))->sin_addr;
} else {
m_freem(m);
return ENETUNREACH;
}
} else {
/* bidirectional configured tunnel mode */
if (sin_dst->sin_addr.s_addr != INADDR_ANY)
iphdr.ip_dst = sin_dst->sin_addr;
else {
m_freem(m);
return ENETUNREACH;
}
}
iphdr.ip_p = proto;
/* version will be set in ip_output() */
iphdr.ip_ttl = ip_gif_ttl;
iphdr.ip_len = m->m_pkthdr.len + sizeof(struct ip);
if (ifp->if_flags & IFF_LINK1)
ip_ecn_ingress(ECN_ALLOWED, &iphdr.ip_tos, &tos);
/* prepend new IP header */
M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
if (m && m->m_len < sizeof(struct ip))
m = m_pullup(m, sizeof(struct ip));
if (m == NULL) {
printf("ENOBUFS in in_gif_output %d\n", __LINE__);
return ENOBUFS;
}
*(mtod(m, struct ip *)) = iphdr;
if (dst->sin_family != sin_dst->sin_family ||
dst->sin_addr.s_addr != sin_dst->sin_addr.s_addr) {
/* cache route doesn't match */
dst->sin_family = sin_dst->sin_family;
dst->sin_len = sizeof(struct sockaddr_in);
dst->sin_addr = sin_dst->sin_addr;
if (sc->gif_ro.ro_rt) {
RTFREE(sc->gif_ro.ro_rt);
sc->gif_ro.ro_rt = NULL;
}
}
if (sc->gif_ro.ro_rt == NULL) {
rtalloc(&sc->gif_ro);
if (sc->gif_ro.ro_rt == NULL) {
m_freem(m);
return ENETUNREACH;
}
}
error = ip_output(m, 0, &sc->gif_ro, 0, 0);
return(error);
}
void
in_gif_input(struct mbuf *m, int off, int proto)
{
struct gif_softc *sc;
struct ifnet *gifp = NULL;
struct ip *ip;
int i, af;
u_int8_t otos;
ip = mtod(m, struct ip *);
/* this code will be soon improved. */
#define satosin(sa) ((struct sockaddr_in *)(sa))
for (i = 0, sc = gif; i < ngif; i++, sc++) {
if (sc->gif_psrc == NULL
|| sc->gif_pdst == NULL
|| sc->gif_psrc->sa_family != AF_INET
|| sc->gif_pdst->sa_family != AF_INET) {
continue;
}
if ((sc->gif_if.if_flags & IFF_UP) == 0)
continue;
#ifdef INET6
/* XXX: temporal stf support hack */
if (proto == IPPROTO_IPV6 &&
bcmp(sc->gif_if.if_name, "stf", 3) == 0 &&
(satosin(sc->gif_psrc)->sin_addr.s_addr ==
ip->ip_dst.s_addr ||
IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) &&
satosin(sc->gif_pdst)->sin_addr.s_addr ==
INADDR_BROADCAST) {
gifp = &sc->gif_if;
break;
}
#endif
if ((sc->gif_if.if_flags & IFF_LINK0)
&& satosin(sc->gif_psrc)->sin_addr.s_addr == ip->ip_dst.s_addr
&& satosin(sc->gif_pdst)->sin_addr.s_addr == INADDR_ANY) {
gifp = &sc->gif_if;
continue;
}
if (satosin(sc->gif_psrc)->sin_addr.s_addr == ip->ip_dst.s_addr
&& satosin(sc->gif_pdst)->sin_addr.s_addr == ip->ip_src.s_addr)
{
gifp = &sc->gif_if;
break;
}
}
if (gifp == NULL) {
#ifdef MROUTING
/* for backward compatibility */
if (proto == IPPROTO_IPV4) {
ipip_input(m, off, proto);
return;
}
#endif /*MROUTING*/
m_freem(m);
ipstat.ips_nogif++;
return;
}
otos = ip->ip_tos;
m_adj(m, off);
switch (proto) {
case IPPROTO_IPV4:
{
struct ip *ip;
#ifdef INET6
if (bcmp(gifp->if_name, "stf", 3) == 0) {
m_freem(m);
return;
}
#endif
af = AF_INET;
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (!m)
return;
}
ip = mtod(m, struct ip *);
if (gifp->if_flags & IFF_LINK1)
ip_ecn_egress(ECN_ALLOWED, &otos, &ip->ip_tos);
break;
}
#ifdef INET6
case IPPROTO_IPV6:
{
struct ip6_hdr *ip6;
u_int8_t itos;
af = AF_INET6;
if (m->m_len < sizeof(*ip6)) {
m = m_pullup(m, sizeof(*ip6));
if (!m)
return;
}
ip6 = mtod(m, struct ip6_hdr *);
itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
if (gifp->if_flags & IFF_LINK1)
ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
ip6->ip6_flow &= ~htonl(0xff << 20);
ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
break;
}
#endif /* INET6 */
default:
ipstat.ips_nogif++;
m_freem(m);
return;
}
gif_input(m, af, gifp);
return;
}