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|
/* $OpenBSD: if_gif.c,v 1.75 2015/06/30 13:54:42 mpi Exp $ */
/* $KAME: if_gif.c,v 1.43 2001/02/20 08:51:07 itojun 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/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/bpf.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_gif.h>
#include <netinet/ip.h>
#include <netinet/ip_ether.h>
#include <netinet/ip_var.h>
#ifdef INET6
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_gif.h>
#endif /* INET6 */
#include <net/if_gif.h>
#include "bpfilter.h"
#include "bridge.h"
void gifattach(int);
int gif_clone_create(struct if_clone *, int);
int gif_clone_destroy(struct ifnet *);
int gif_checkloop(struct ifnet *, struct mbuf *);
/*
* gif global variable definitions
*/
struct gif_softc_head gif_softc_list;
struct if_clone gif_cloner =
IF_CLONE_INITIALIZER("gif", gif_clone_create, gif_clone_destroy);
/* ARGSUSED */
void
gifattach(int count)
{
LIST_INIT(&gif_softc_list);
if_clone_attach(&gif_cloner);
}
int
gif_clone_create(struct if_clone *ifc, int unit)
{
struct gif_softc *sc;
int s;
sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT|M_ZERO);
if (!sc)
return (ENOMEM);
snprintf(sc->gif_if.if_xname, sizeof sc->gif_if.if_xname,
"%s%d", ifc->ifc_name, unit);
sc->gif_if.if_mtu = GIF_MTU;
sc->gif_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
sc->gif_if.if_ioctl = gif_ioctl;
sc->gif_if.if_start = gif_start;
sc->gif_if.if_output = gif_output;
sc->gif_if.if_type = IFT_GIF;
IFQ_SET_MAXLEN(&sc->gif_if.if_snd, IFQ_MAXLEN);
IFQ_SET_READY(&sc->gif_if.if_snd);
sc->gif_if.if_softc = sc;
if_attach(&sc->gif_if);
if_alloc_sadl(&sc->gif_if);
#if NBPFILTER > 0
bpfattach(&sc->gif_if.if_bpf, &sc->gif_if, DLT_LOOP, sizeof(u_int32_t));
#endif
s = splnet();
LIST_INSERT_HEAD(&gif_softc_list, sc, gif_list);
splx(s);
return (0);
}
int
gif_clone_destroy(struct ifnet *ifp)
{
struct gif_softc *sc = ifp->if_softc;
int s;
s = splnet();
LIST_REMOVE(sc, gif_list);
splx(s);
if_detach(ifp);
if (sc->gif_psrc)
free((caddr_t)sc->gif_psrc, M_IFADDR, 0);
sc->gif_psrc = NULL;
if (sc->gif_pdst)
free((caddr_t)sc->gif_pdst, M_IFADDR, 0);
sc->gif_pdst = NULL;
free(sc, M_DEVBUF, sizeof(*sc));
return (0);
}
void
gif_start(struct ifnet *ifp)
{
struct gif_softc *sc = (struct gif_softc*)ifp;
struct mbuf *m;
int s;
while (1) {
s = splnet();
IFQ_DEQUEUE(&ifp->if_snd, m);
splx(s);
if (m == NULL)
break;
/* is interface up and usable? */
if ((ifp->if_flags & (IFF_OACTIVE | IFF_UP)) != IFF_UP ||
sc->gif_psrc == NULL || sc->gif_pdst == NULL ||
sc->gif_psrc->sa_family != sc->gif_pdst->sa_family) {
m_freem(m);
continue;
}
/*
* Check if the packet is coming via bridge and needs
* etherip encapsulation or not. bridge(4) directly calls
* the start function and bypasses the if_output function
* so we need to do the encap here.
*/
if (ifp->if_bridgeport && (m->m_flags & M_PROTO1)) {
int error = 0;
/*
* Remove multicast and broadcast flags or encapsulated
* packet ends up as multicast or broadcast packet.
*/
m->m_flags &= ~(M_BCAST|M_MCAST);
switch (sc->gif_psrc->sa_family) {
case AF_INET:
error = in_gif_output(ifp, AF_LINK, &m);
break;
#ifdef INET6
case AF_INET6:
error = in6_gif_output(ifp, AF_LINK, &m);
break;
#endif
default:
error = EAFNOSUPPORT;
m_freem(m);
break;
}
if (error)
continue;
if (gif_checkloop(ifp, m))
continue;
}
#if NBPFILTER > 0
if (ifp->if_bpf) {
int offset;
sa_family_t family;
u_int8_t proto;
/* must decapsulate outer header for bpf */
switch (sc->gif_psrc->sa_family) {
case AF_INET:
offset = sizeof(struct ip);
proto = mtod(m, struct ip *)->ip_p;
break;
#ifdef INET6
case AF_INET6:
offset = sizeof(struct ip6_hdr);
proto = mtod(m, struct ip6_hdr *)->ip6_nxt;
break;
#endif
default:
proto = 0;
break;
}
switch (proto) {
case IPPROTO_IPV4:
family = AF_INET;
break;
case IPPROTO_IPV6:
family = AF_INET6;
break;
case IPPROTO_ETHERIP:
family = AF_LINK;
offset += sizeof(struct etherip_header);
break;
case IPPROTO_MPLS:
family = AF_MPLS;
break;
default:
offset = 0;
family = sc->gif_psrc->sa_family;
break;
}
m->m_data += offset;
m->m_len -= offset;
m->m_pkthdr.len -= offset;
bpf_mtap_af(ifp->if_bpf, family, m, BPF_DIRECTION_OUT);
m->m_data -= offset;
m->m_len += offset;
m->m_pkthdr.len += offset;
}
#endif
ifp->if_opackets++;
/* XXX we should cache the outgoing route */
switch (sc->gif_psrc->sa_family) {
case AF_INET:
ip_output(m, NULL, NULL, 0, NULL, NULL, 0);
break;
#ifdef INET6
case AF_INET6:
/*
* 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.
*/
ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL);
break;
#endif
default:
m_freem(m);
break;
}
}
}
int
gif_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
struct rtentry *rt)
{
struct gif_softc *sc = (struct gif_softc*)ifp;
int error = 0;
if (!(ifp->if_flags & IFF_UP) ||
sc->gif_psrc == NULL || sc->gif_pdst == NULL ||
sc->gif_psrc->sa_family != sc->gif_pdst->sa_family) {
m_freem(m);
error = ENETDOWN;
goto end;
}
/*
* Remove multicast and broadcast flags or encapsulated packet
* ends up as multicast or broadcast packet.
*/
m->m_flags &= ~(M_BCAST|M_MCAST);
/*
* Encapsulate packet. Add IP or IP6 header depending on tunnel AF.
*/
switch (sc->gif_psrc->sa_family) {
case AF_INET:
error = in_gif_output(ifp, dst->sa_family, &m);
break;
#ifdef INET6
case AF_INET6:
error = in6_gif_output(ifp, dst->sa_family, &m);
break;
#endif
default:
m_freem(m);
error = EAFNOSUPPORT;
break;
}
if (error)
goto end;
if ((error = gif_checkloop(ifp, m)))
goto end;
error = if_enqueue(ifp, m);
end:
if (error)
ifp->if_oerrors++;
return (error);
}
int
gif_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
struct gif_softc *sc = (struct gif_softc*)ifp;
struct ifreq *ifr = (struct ifreq *)data;
struct ifaddr *ifa = (struct ifaddr *)data;
int error = 0, size;
struct sockaddr *dst, *src;
struct sockaddr *sa;
int s;
struct gif_softc *sc2;
switch (cmd) {
case SIOCSIFADDR:
ifa->ifa_rtrequest = p2p_rtrequest;
break;
case SIOCSIFDSTADDR:
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
break;
case SIOCSIFPHYADDR:
#ifdef INET6
case SIOCSIFPHYADDR_IN6:
#endif /* INET6 */
case SIOCSLIFPHYADDR:
switch (cmd) {
case SIOCSIFPHYADDR:
src = (struct sockaddr *)
&(((struct in_aliasreq *)data)->ifra_addr);
dst = (struct sockaddr *)
&(((struct in_aliasreq *)data)->ifra_dstaddr);
break;
#ifdef INET6
case SIOCSIFPHYADDR_IN6:
src = (struct sockaddr *)
&(((struct in6_aliasreq *)data)->ifra_addr);
dst = (struct sockaddr *)
&(((struct in6_aliasreq *)data)->ifra_dstaddr);
break;
#endif
case SIOCSLIFPHYADDR:
src = (struct sockaddr *)
&(((struct if_laddrreq *)data)->addr);
dst = (struct sockaddr *)
&(((struct if_laddrreq *)data)->dstaddr);
break;
default:
return (EINVAL);
}
/* sa_family must be equal */
if (src->sa_family != dst->sa_family)
return (EINVAL);
/* validate sa_len */
switch (src->sa_family) {
case AF_INET:
if (src->sa_len != sizeof(struct sockaddr_in))
return (EINVAL);
break;
#ifdef INET6
case AF_INET6:
if (src->sa_len != sizeof(struct sockaddr_in6))
return (EINVAL);
break;
#endif
default:
return (EAFNOSUPPORT);
}
switch (dst->sa_family) {
case AF_INET:
if (dst->sa_len != sizeof(struct sockaddr_in))
return (EINVAL);
break;
#ifdef INET6
case AF_INET6:
if (dst->sa_len != sizeof(struct sockaddr_in6))
return (EINVAL);
break;
#endif
default:
return (EAFNOSUPPORT);
}
/* check sa_family looks sane for the cmd */
switch (cmd) {
case SIOCSIFPHYADDR:
if (src->sa_family == AF_INET)
break;
return (EAFNOSUPPORT);
#ifdef INET6
case SIOCSIFPHYADDR_IN6:
if (src->sa_family == AF_INET6)
break;
return (EAFNOSUPPORT);
#endif /* INET6 */
case SIOCSLIFPHYADDR:
/* checks done in the above */
break;
}
LIST_FOREACH(sc2, &gif_softc_list, gif_list) {
if (sc2 == sc)
continue;
if (!sc2->gif_pdst || !sc2->gif_psrc)
continue;
if (sc2->gif_pdst->sa_family != dst->sa_family ||
sc2->gif_pdst->sa_len != dst->sa_len ||
sc2->gif_psrc->sa_family != src->sa_family ||
sc2->gif_psrc->sa_len != src->sa_len)
continue;
/* can't configure same pair of address onto two gifs */
if (bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
error = EADDRNOTAVAIL;
goto bad;
}
/* can't configure multiple multi-dest interfaces */
#define multidest(x) \
(((struct sockaddr_in *)(x))->sin_addr.s_addr == INADDR_ANY)
#ifdef INET6
#define multidest6(x) \
(IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)(x))->sin6_addr))
#endif
if (dst->sa_family == AF_INET &&
multidest(dst) && multidest(sc2->gif_pdst)) {
error = EADDRNOTAVAIL;
goto bad;
}
#ifdef INET6
if (dst->sa_family == AF_INET6 &&
multidest6(dst) && multidest6(sc2->gif_pdst)) {
error = EADDRNOTAVAIL;
goto bad;
}
#endif
}
if (sc->gif_psrc)
free((caddr_t)sc->gif_psrc, M_IFADDR, 0);
sa = malloc(src->sa_len, M_IFADDR, M_WAITOK);
bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
sc->gif_psrc = sa;
if (sc->gif_pdst)
free((caddr_t)sc->gif_pdst, M_IFADDR, 0);
sa = malloc(dst->sa_len, M_IFADDR, M_WAITOK);
bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
sc->gif_pdst = sa;
s = splnet();
ifp->if_flags |= IFF_RUNNING;
if_up(ifp); /* send up RTM_IFINFO */
splx(s);
error = 0;
break;
#ifdef SIOCDIFPHYADDR
case SIOCDIFPHYADDR:
if (sc->gif_psrc) {
free((caddr_t)sc->gif_psrc, M_IFADDR, 0);
sc->gif_psrc = NULL;
}
if (sc->gif_pdst) {
free((caddr_t)sc->gif_pdst, M_IFADDR, 0);
sc->gif_pdst = NULL;
}
/* change the IFF_{UP, RUNNING} flag as well? */
break;
#endif
case SIOCGIFPSRCADDR:
#ifdef INET6
case SIOCGIFPSRCADDR_IN6:
#endif /* INET6 */
if (sc->gif_psrc == NULL) {
error = EADDRNOTAVAIL;
goto bad;
}
src = sc->gif_psrc;
switch (cmd) {
case SIOCGIFPSRCADDR:
dst = &ifr->ifr_addr;
size = sizeof(ifr->ifr_addr);
break;
#ifdef INET6
case SIOCGIFPSRCADDR_IN6:
dst = (struct sockaddr *)
&(((struct in6_ifreq *)data)->ifr_addr);
size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
break;
#endif /* INET6 */
default:
error = EADDRNOTAVAIL;
goto bad;
}
if (src->sa_len > size)
return (EINVAL);
bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
break;
case SIOCGIFPDSTADDR:
#ifdef INET6
case SIOCGIFPDSTADDR_IN6:
#endif /* INET6 */
if (sc->gif_pdst == NULL) {
error = EADDRNOTAVAIL;
goto bad;
}
src = sc->gif_pdst;
switch (cmd) {
case SIOCGIFPDSTADDR:
dst = &ifr->ifr_addr;
size = sizeof(ifr->ifr_addr);
break;
#ifdef INET6
case SIOCGIFPDSTADDR_IN6:
dst = (struct sockaddr *)
&(((struct in6_ifreq *)data)->ifr_addr);
size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
break;
#endif /* INET6 */
default:
error = EADDRNOTAVAIL;
goto bad;
}
if (src->sa_len > size)
return (EINVAL);
bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
break;
case SIOCGLIFPHYADDR:
if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
error = EADDRNOTAVAIL;
goto bad;
}
/* copy src */
src = sc->gif_psrc;
dst = (struct sockaddr *)
&(((struct if_laddrreq *)data)->addr);
size = sizeof(((struct if_laddrreq *)data)->addr);
if (src->sa_len > size)
return (EINVAL);
bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
/* copy dst */
src = sc->gif_pdst;
dst = (struct sockaddr *)
&(((struct if_laddrreq *)data)->dstaddr);
size = sizeof(((struct if_laddrreq *)data)->dstaddr);
if (src->sa_len > size)
return (EINVAL);
bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
break;
case SIOCSIFFLAGS:
/* if_ioctl() takes care of it */
break;
case SIOCSIFMTU:
if (ifr->ifr_mtu < GIF_MTU_MIN || ifr->ifr_mtu > GIF_MTU_MAX)
error = EINVAL;
else
ifp->if_mtu = ifr->ifr_mtu;
break;
case SIOCSLIFPHYRTABLE:
if (ifr->ifr_rdomainid < 0 ||
ifr->ifr_rdomainid > RT_TABLEID_MAX ||
!rtable_exists(ifr->ifr_rdomainid)) {
error = EINVAL;
break;
}
sc->gif_rtableid = ifr->ifr_rdomainid;
break;
case SIOCGLIFPHYRTABLE:
ifr->ifr_rdomainid = sc->gif_rtableid;
break;
default:
error = ENOTTY;
break;
}
bad:
return (error);
}
int
gif_checkloop(struct ifnet *ifp, struct mbuf *m)
{
struct m_tag *mtag;
/*
* gif may cause infinite recursion calls when misconfigured.
* We'll prevent this by detecting loops.
*/
for (mtag = m_tag_find(m, PACKET_TAG_GIF, NULL); mtag;
mtag = m_tag_find(m, PACKET_TAG_GIF, mtag)) {
if (*(struct ifnet **)(mtag + 1) == ifp) {
log(LOG_NOTICE, "gif_output: "
"recursively called too many times\n");
m_freem(m);
return ENETUNREACH;
}
}
mtag = m_tag_get(PACKET_TAG_GIF, sizeof(struct ifnet *), M_NOWAIT);
if (mtag == NULL) {
m_freem(m);
return ENOMEM;
}
*(struct ifnet **)(mtag + 1) = ifp;
m_tag_prepend(m, mtag);
return 0;
}
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