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/*-
* 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.
*
* $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/rmlock.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/queue.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
#include <sys/protosw.h>
#include <sys/malloc.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#ifdef INET
#include <netinet/ip.h>
#endif
#include <netinet/ip_encap.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_var.h>
#endif
#include <netinet/ip_ecn.h>
#ifdef INET6
#include <netinet6/ip6_ecn.h>
#endif
#include <net/if_gif.h>
#define GIF_HLIM 30
static VNET_DEFINE(int, ip6_gif_hlim) = GIF_HLIM;
#define V_ip6_gif_hlim VNET(ip6_gif_hlim)
SYSCTL_DECL(_net_inet6_ip6);
SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(ip6_gif_hlim), 0, "");
int in6_gif_output(struct ifnet *, struct mbuf *, int, uint8_t);
int in6_gif_encapcheck(const struct mbuf *, int, int, void *);
int in6_gif_attach(struct gif_softc *);
static int gif_validate6(const struct ip6_hdr *, struct gif_softc *,
struct ifnet *);
static int in6_gif_input(struct mbuf **, int *, int);
extern struct domain inet6domain;
static struct protosw in6_gif_protosw = {
.pr_type = SOCK_RAW,
.pr_domain = &inet6domain,
.pr_protocol = 0, /* IPPROTO_IPV[46] */
.pr_flags = PR_ATOMIC|PR_ADDR,
.pr_input = in6_gif_input,
.pr_output = rip6_output,
.pr_ctloutput = rip6_ctloutput,
.pr_usrreqs = &rip6_usrreqs
};
int
in6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn)
{
GIF_RLOCK_TRACKER;
struct gif_softc *sc = ifp->if_softc;
struct ip6_hdr *ip6;
int len;
/* prepend new IP header */
len = sizeof(struct ip6_hdr);
#ifndef __NO_STRICT_ALIGNMENT
if (proto == IPPROTO_ETHERIP)
len += ETHERIP_ALIGN;
#endif
M_PREPEND(m, len, M_NOWAIT);
if (m == NULL)
return (ENOBUFS);
#ifndef __NO_STRICT_ALIGNMENT
if (proto == IPPROTO_ETHERIP) {
len = mtod(m, vm_offset_t) & 3;
KASSERT(len == 0 || len == ETHERIP_ALIGN,
("in6_gif_output: unexpected misalignment"));
m->m_data += len;
m->m_len -= ETHERIP_ALIGN;
}
#endif
ip6 = mtod(m, struct ip6_hdr *);
GIF_RLOCK(sc);
if (sc->gif_family != AF_INET6) {
m_freem(m);
GIF_RUNLOCK(sc);
return (ENETDOWN);
}
bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr));
GIF_RUNLOCK(sc);
ip6->ip6_flow |= htonl((uint32_t)ecn << 20);
ip6->ip6_nxt = proto;
ip6->ip6_hlim = V_ip6_gif_hlim;
/*
* 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.
*/
return (ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL));
}
static int
in6_gif_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m = *mp;
struct ifnet *gifp;
struct gif_softc *sc;
struct ip6_hdr *ip6;
uint8_t ecn;
sc = encap_getarg(m);
if (sc == NULL) {
m_freem(m);
IP6STAT_INC(ip6s_nogif);
return (IPPROTO_DONE);
}
gifp = GIF2IFP(sc);
if ((gifp->if_flags & IFF_UP) != 0) {
ip6 = mtod(m, struct ip6_hdr *);
ecn = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
m_adj(m, *offp);
gif_input(m, gifp, proto, ecn);
} else {
m_freem(m);
IP6STAT_INC(ip6s_nogif);
}
return (IPPROTO_DONE);
}
/*
* validate outer address.
*/
static int
gif_validate6(const struct ip6_hdr *ip6, struct gif_softc *sc,
struct ifnet *ifp)
{
GIF_RLOCK_ASSERT(sc);
/*
* Check for address match. Note that the check is for an incoming
* packet. We should compare the *source* address in our configuration
* and the *destination* address of the packet, and vice versa.
*/
if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src, &ip6->ip6_dst) ||
!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst, &ip6->ip6_src))
return (0);
/* martian filters on outer source - done in ip6_input */
/* ingress filters on outer source */
if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
struct sockaddr_in6 sin6;
struct rtentry *rt;
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
sin6.sin6_addr = ip6->ip6_src;
sin6.sin6_scope_id = 0; /* XXX */
rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL,
sc->gif_fibnum);
if (!rt || rt->rt_ifp != ifp) {
if (rt)
RTFREE_LOCKED(rt);
return (0);
}
RTFREE_LOCKED(rt);
}
return (128 * 2);
}
/*
* we know that we are in IFF_UP, outer address available, and outer family
* matched the physical addr family. see gif_encapcheck().
*/
int
in6_gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
{
struct ip6_hdr ip6;
struct gif_softc *sc;
struct ifnet *ifp;
/* sanity check done in caller */
sc = (struct gif_softc *)arg;
GIF_RLOCK_ASSERT(sc);
m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6);
ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL;
return (gif_validate6(&ip6, sc, ifp));
}
int
in6_gif_attach(struct gif_softc *sc)
{
KASSERT(sc->gif_ecookie == NULL, ("gif_ecookie isn't NULL"));
sc->gif_ecookie = encap_attach_func(AF_INET6, -1, gif_encapcheck,
(void *)&in6_gif_protosw, sc);
if (sc->gif_ecookie == NULL)
return (EEXIST);
return (0);
}
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