NetBSD-5.0.2/sys/netinet6/ip6_etherip.c
/* $NetBSD: ip6_etherip.c,v 1.11 2008/10/19 23:28:31 hans Exp $ */
/*
* Copyright (c) 2006, Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
* 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 Hans Rosenfeld nor the names of his
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
*
* 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>
__KERNEL_RCSID(0, "$NetBSD: ip6_etherip.c,v 1.11 2008/10/19 23:28:31 hans Exp $");
#include "opt_inet.h"
#include "bpfilter.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/device.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/syslog.h>
#include <sys/protosw.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#ifdef INET
#include <netinet/ip.h>
#endif
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/ip6_private.h>
#include <netinet6/in6_var.h>
#include <netinet6/ip6_etherip.h>
#endif
#include <net/if_ether.h>
#include <net/if_media.h>
#include <net/if_etherip.h>
#if NBPFILTER > 0
#include <net/bpf.h>
#endif
#include <machine/stdarg.h>
int
ip6_etherip_output(struct ifnet *ifp, struct mbuf *m)
{
struct rtentry *rt;
struct etherip_softc *sc = (struct etherip_softc *)ifp->if_softc;
struct sockaddr_in6 *sin6_src, *sin6_dst;
struct ip6_hdr *ip6; /* capsule IP header, host byte ordered */
struct etherip_header eiphdr;
int proto, error;
union {
struct sockaddr dst;
struct sockaddr_in6 dst6;
} u;
sin6_src = (struct sockaddr_in6 *)sc->sc_src;
sin6_dst = (struct sockaddr_in6 *)sc->sc_dst;
if (sin6_src == NULL ||
sin6_dst == NULL ||
sin6_src->sin6_family != AF_INET6 ||
sin6_dst->sin6_family != AF_INET6) {
m_freem(m);
return EAFNOSUPPORT;
}
/* reset broadcast/multicast flags */
m->m_flags &= ~(M_BCAST|M_MCAST);
m->m_flags |= M_PKTHDR;
proto = IPPROTO_ETHERIP;
/* fill and prepend Ethernet-in-IP header */
eiphdr.eip_ver = ETHERIP_VERSION & ETHERIP_VER_VERS_MASK;
eiphdr.eip_pad = 0;
M_PREPEND(m, sizeof(struct etherip_header), M_DONTWAIT);
if (m == NULL)
return ENOBUFS;
if (M_UNWRITABLE(m, sizeof(struct etherip_header))) {
m = m_pullup(m, sizeof(struct etherip_header));
if (m == NULL)
return ENOBUFS;
}
memcpy(mtod(m, struct etherip_header *), &eiphdr,
sizeof(struct etherip_header));
/* prepend new IP header */
M_PREPEND(m, sizeof(struct ip6_hdr), M_DONTWAIT);
if (m && m->m_len < sizeof(struct ip6_hdr))
m = m_pullup(m, sizeof(struct ip6_hdr));
if (m == NULL)
return ENOBUFS;
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_nxt = proto;
ip6->ip6_hlim = ETHERIP_TTL;
ip6->ip6_src = sin6_src->sin6_addr;
/* bidirectional configured tunnel mode */
if (!IN6_IS_ADDR_UNSPECIFIED(&sin6_dst->sin6_addr))
ip6->ip6_dst = sin6_dst->sin6_addr;
else {
m_freem(m);
return ENETUNREACH;
}
sockaddr_in6_init(&u.dst6, &sin6_dst->sin6_addr, 0, 0, 0);
if ((rt = rtcache_lookup(&sc->sc_ro, &u.dst)) == NULL) {
m_freem(m);
return ENETUNREACH;
}
/* if it constitutes infinite encapsulation, punt. */
if (rt->rt_ifp == ifp) {
rtcache_free(&sc->sc_ro);
m_freem(m);
return ENETUNREACH; /* XXX */
}
/*
* force fragmentation to minimum MTU, to avoid path MTU discovery.
* it is too painful to ask for resend of inner packet, to achieve
* path MTU discovery for encapsulated packets.
*/
error = ip6_output(m, 0, &sc->sc_ro, IPV6_MINMTU, NULL, NULL, NULL);
return error;
}
int
ip6_etherip_input(struct mbuf *m, ...)
{
struct etherip_softc *sc;
const struct ip6_hdr *ip6;
struct sockaddr_in6 *src6, *dst6;
struct ifnet *ifp = NULL;
int off, proto, s;
va_list ap;
va_start(ap, m);
off = va_arg(ap, int);
proto = va_arg(ap, int);
va_end(ap);
if (proto != IPPROTO_ETHERIP) {
m_freem(m);
IP6_STATINC(IP6_STAT_NOGIF);
return IPPROTO_DONE;
}
ip6 = mtod(m, const struct ip6_hdr *);
/* find device configured for this packets src and dst */
LIST_FOREACH(sc, ðerip_softc_list, etherip_list) {
if( !sc->sc_src || !sc->sc_dst)
continue;
if (sc->sc_src->sa_family != AF_INET6 ||
sc->sc_dst->sa_family != AF_INET6)
continue;
src6 = (struct sockaddr_in6 *)sc->sc_src;
dst6 = (struct sockaddr_in6 *)sc->sc_dst;
if (!IN6_ARE_ADDR_EQUAL(&src6->sin6_addr, &ip6->ip6_dst) ||
!IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_src))
continue;
ifp = &sc->sc_ec.ec_if;
break;
}
/* no matching device found */
if (!ifp) {
m_freem(m);
IP6_STATINC(IP6_STAT_ODROPPED);
return IPPROTO_DONE;
}
m_adj(m, off);
/*
* Section 4 of RFC 3378 requires that the EtherIP header of incoming
* packets is verified to contain the correct values in the version and
* reserved fields, and packets with wrong values be dropped.
*
* There is some discussion about what exactly the header should look
* like, the RFC is not very clear there. To be compatible with broken
* implementations, we don't check the header on incoming packets,
* relying on the ethernet code to filter out garbage.
*
* The header we use for sending is compatible with the original
* implementation in OpenBSD, which was used in former NetBSD versions
* and is used in FreeBSD. One Linux implementation is known to use the
* same value.
*/
m_adj(m, sizeof(struct etherip_header));
m = m_pullup(m, sizeof(struct ether_header));
if (m == NULL) {
ifp->if_ierrors++;
return IPPROTO_DONE;
}
m->m_pkthdr.rcvif = ifp;
m->m_flags &= ~(M_BCAST|M_MCAST);
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m);
#endif
ifp->if_ipackets++;
s = splnet();
(ifp->if_input)(ifp, m);
splx(s);
return IPPROTO_DONE;
}