NetBSD/sys/netinet/ip_ipip.c

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/* $NetBSD: ip_ipip.c,v 1.7 1999/08/26 02:56:59 itojun Exp $ */
/*-
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center; Heiko W.Rupp <hwr@pilhuhn.de>.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Encapsulate for and decapsulate packets received on an IP-in-IP tunnel.
*
* See: RFC 2003.
*/
#include "ipip.h"
#include "opt_mrouting.h"
#include "opt_ipsec.h"
#if NIPIP > 0 || defined(MROUTING)
#include "opt_inet.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <net/if_types.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/ip_ipip.h>
#else
#error IPIP without INET?
#endif
#ifdef MROUTING
#include <netinet/ip_mroute.h>
#endif
#if NIPIP > 0
struct ipip_softc *ipip_softc;
int ipip_nsoftc;
struct ipip_softc *ipip_lookup __P((struct mbuf *));
void ipipattach __P((int));
int ipip_output __P((struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *));
int ipip_ioctl __P((struct ifnet *, u_long, caddr_t));
void ipip_compute_route __P((struct ipip_softc *));
#endif /* NIPIP > 0 */
#include <machine/stdarg.h>
/*
* Note this is a common IP-in-IP input for both ipip `interfaces'
* and the multicast routing code's IP-in-IP needs.
*/
void
#if __STDC__
ipip_input(struct mbuf *m, ...)
#else
ipip_input(m, va_alist)
sruct mbuf *m;
va_dcl
#endif
{
#if NIPIP > 0
struct ipip_softc *sc;
#endif
int hlen;
va_list ap;
va_start(ap, m);
hlen = va_arg(ap, int);
va_end(ap);
#if NIPIP > 0
/*
* First, we try to match an ipip tunnel.
*/
if ((sc = ipip_lookup(m)) != NULL) {
int s;
sc->sc_if.if_ipackets++;
sc->sc_if.if_ibytes += m->m_pkthdr.len;
m_adj(m, hlen);
m->m_pkthdr.rcvif = &sc->sc_if;
s = splimp();
if (IF_QFULL(&ipintrq)) {
IF_DROP(&ipintrq);
m_freem(m);
} else {
IF_ENQUEUE(&ipintrq, m);
/*
* No need to reschedule an IP netisr, since
* ipintr() will simply continue looping and
* see the packet we just enqueued.
*/
}
splx(s);
/* No more processing at this level. */
return;
}
#endif /* NIPIP > 0 */
#ifdef MROUTING
/*
* Next, give the multicast routing code a chance to grab
* this packet.
*/
if (mrt_ipip_input(m, hlen)) {
/*
* Multicast routing code claimed this one. No
* more processing at this level.
*/
return;
}
#endif /* MROUTING */
/* Last try: give it to raw IP. */
rip_input(m);
}
#if NIPIP > 0
/*
* Find the ipip interface associated with our src/dst.
*/
struct ipip_softc *
ipip_lookup(m)
struct mbuf *m;
{
struct ip *ip = mtod(m, struct ip *);
struct ipip_softc *sc;
int i;
for (i = 0; i < ipip_nsoftc; i++) {
sc = &ipip_softc[i];
if ((sc->sc_if.if_flags & IFF_UP) != 0 &&
in_hosteq(sc->sc_dst, ip->ip_src) &&
in_hosteq(sc->sc_src, ip->ip_dst))
return (sc);
}
return (NULL);
}
/*
* Attach the IPIP pseudo-devices.
*/
/* ARGSUSED */
void
ipipattach(count)
int count;
{
struct ipip_softc *sc;
size_t size;
int i;
ipip_nsoftc = count;
size = sizeof(struct ipip_softc) * count;
ipip_softc = malloc(size, M_DEVBUF, M_WAITOK);
memset(ipip_softc, 0, size);
for (i = 0; i < ipip_nsoftc; i++) {
sc = &ipip_softc[i];
sprintf(sc->sc_if.if_xname, "ipip%d", i);
sc->sc_if.if_softc = sc;
sc->sc_if.if_type = IFT_OTHER;
sc->sc_if.if_addrlen = sizeof(struct in_addr);
sc->sc_if.if_hdrlen = sizeof(struct ip);
sc->sc_if.if_mtu = 0; /* filled in later */
sc->sc_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
sc->sc_if.if_output = ipip_output;
sc->sc_if.if_ioctl = ipip_ioctl;
sc->sc_src.s_addr = INADDR_ANY;
sc->sc_dst.s_addr = INADDR_ANY;
if_attach(&sc->sc_if);
#if NBPFILTER > 0
bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_NULL,
sc->sc_if.if_hdrlen);
#endif
}
}
int
ipip_output(ifp, m0, dst, rt)
struct ifnet *ifp;
struct mbuf *m0;
struct sockaddr *dst;
struct rtentry *rt;
{
struct ipip_softc *sc = ifp->if_softc;
struct ip *nip, *ip;
int error;
if (dst->sa_family != AF_INET) {
IF_DROP(&ifp->if_snd);
m_freem(m0);
return (EAFNOSUPPORT);
}
ip = mtod(m0, struct ip *);
/* Add the new IP header. */
M_PREPEND(m0, sizeof(struct ip), M_DONTWAIT);
if (m0 == NULL)
return (ENOBUFS);
nip = mtod(m0, struct ip *);
memset(nip, 0, sizeof(*nip));
nip->ip_hl = sizeof(*nip) >> 2;
nip->ip_tos = ip->ip_tos;
nip->ip_len = m0->m_pkthdr.len;
nip->ip_ttl = ip->ip_ttl;
nip->ip_p = IPPROTO_IPIP;
nip->ip_src = sc->sc_src;
nip->ip_dst = sc->sc_dst;
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m0);
#endif
ifp->if_opackets++;
ifp->if_obytes += m0->m_pkthdr.len;
#ifdef IPSEC
m0->m_pkthdr.rcvif = NULL;
#endif
error = ip_output(m0, NULL, &sc->sc_route, 0, NULL);
if (error)
ifp->if_oerrors++;
return (error);
}
int
ipip_ioctl(ifp, cmd, data)
struct ifnet *ifp;
u_long cmd;
caddr_t data;
{
struct ipip_softc *sc = ifp->if_softc;
struct ifaddr *ifa = (struct ifaddr *)data;
struct in_ifaddr *ia = (struct in_ifaddr *)data;
struct ifreq *ifr = (struct ifreq *)data;
int s, error = 0;
s = splnet();
switch (cmd) {
case SIOCSIFADDR:
case SIOCSIFDSTADDR:
if (ifa->ifa_addr->sa_family != AF_INET) {
error = EAFNOSUPPORT;
break;
}
sc->sc_src = (satosin(ifa->ifa_addr))->sin_addr;
sc->sc_dst = ia->ia_dstaddr.sin_addr;
ifp->if_mtu = 0;
ifp->if_flags &= ~IFF_UP;
if (!in_nullhost(sc->sc_src) && !in_nullhost(sc->sc_dst)) {
struct rtentry *rt;
ipip_compute_route(sc);
/*
* Now that we know the route to use, fill in the
* MTU.
*/
rt = sc->sc_route.ro_rt;
if (rt != NULL) {
ifp->if_mtu = rt->rt_ifp->if_mtu -
ifp->if_hdrlen;
ifp->if_flags |= IFF_UP;
}
}
break;
case SIOCSIFFLAGS:
if (in_nullhost(sc->sc_src) || in_nullhost(sc->sc_dst))
ifp->if_flags &= ~IFF_UP;
if (ifp->if_flags & IFF_UP) {
if (sc->sc_route.ro_rt == NULL) {
struct rtentry *rt;
ipip_compute_route(sc);
rt = sc->sc_route.ro_rt;
if (rt != NULL)
ifp->if_mtu = rt->rt_ifp->if_mtu -
ifp->if_hdrlen;
else
ifp->if_flags &= ~IFF_UP;
}
}
else {
if (sc->sc_route.ro_rt != NULL) {
RTFREE(sc->sc_route.ro_rt);
sc->sc_route.ro_rt = NULL;
}
ifp->if_mtu = 0;
}
break;
case SIOCSIFMTU:
if (ifr->ifr_mtu < (IP_MSS - ifp->if_hdrlen)) {
error = EINVAL;
break;
}
if (sc->sc_route.ro_rt != NULL &&
ifr->ifr_mtu > (sc->sc_route.ro_rt->rt_ifp->if_mtu -
ifp->if_hdrlen)) {
error = EINVAL;
break;
}
ifp->if_mtu = ifr->ifr_mtu;
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
if (ifr == NULL || ifr->ifr_addr.sa_family != AF_INET) {
error = EAFNOSUPPORT;
break;
}
break;
default:
error = EINVAL;
}
splx(s);
return (error);
}
/*
* Compute a less-specific route to the destination such that ip_output()
* will not loop the packet back to ipip_output().
*/
void
ipip_compute_route(sc)
struct ipip_softc *sc;
{
struct route *ro;
ro = &sc->sc_route;
if (ro->ro_rt != NULL)
RTFREE(ro->ro_rt);
ro->ro_rt = NULL;
memset(&ro->ro_dst, 0, sizeof(ro->ro_dst));
ro->ro_dst.sa_family = AF_INET;
ro->ro_dst.sa_len = sizeof(ro->ro_dst);
/*
* Toggle the last bit on the address so our interface won't
* match.
*
* XXX What we want here is a flag to exclude picking routes
* XXX with this interface.
*/
((struct sockaddr_in *)&ro->ro_dst)->sin_addr.s_addr =
htonl(ntohl(sc->sc_dst.s_addr) ^ 1);
rtalloc(ro);
/*
* Now change it back, or else ip_ouput() will just drop
* the route and find the one for the ipip interface.
*/
((struct sockaddr_in *)&ro->ro_dst)->sin_addr = sc->sc_dst;
}
#endif /* NIPIP > 0 */
#endif /* NIPIP > 0 || MROUTING */