783 lines
19 KiB
C
783 lines
19 KiB
C
/* $NetBSD: if_stf.c,v 1.36 2003/11/12 13:40:16 cl Exp $ */
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/* $KAME: if_stf.c,v 1.62 2001/06/07 22:32:16 itojun Exp $ */
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/*
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* Copyright (C) 2000 WIDE Project.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the project nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* 6to4 interface, based on RFC3056.
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*
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* 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting.
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* There is no address mapping defined from IPv6 multicast address to IPv4
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* address. Therefore, we do not have IFF_MULTICAST on the interface.
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*
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* Due to the lack of address mapping for link-local addresses, we cannot
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* throw packets toward link-local addresses (fe80::x). Also, we cannot throw
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* packets to link-local multicast addresses (ff02::x).
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*
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* Here are interesting symptoms due to the lack of link-local address:
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*
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* Unicast routing exchange:
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* - RIPng: Impossible. Uses link-local multicast packet toward ff02::9,
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* and link-local addresses as nexthop.
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* - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address
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* assigned to the link, and makes use of them. Also, HELLO packets use
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* link-local multicast addresses (ff02::5 and ff02::6).
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* - BGP4+: Maybe. You can only use global address as nexthop, and global
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* address as TCP endpoint address.
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*
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* Multicast routing protocols:
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* - PIM: Hello packet cannot be used to discover adjacent PIM routers.
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* Adjacent PIM routers must be configured manually (is it really spec-wise
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* correct thing to do?).
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*
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* ICMPv6:
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* - Redirects cannot be used due to the lack of link-local address.
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*
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* stf interface does not have, and will not need, a link-local address.
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* It seems to have no real benefit and does not help the above symptoms much.
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* Even if we assign link-locals to interface, we cannot really
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* use link-local unicast/multicast on top of 6to4 cloud (since there's no
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* encapsulation defined for link-local address), and the above analysis does
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* not change. RFC3056 does not mandate the assignment of link-local address
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* either.
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*
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* 6to4 interface has security issues. Refer to
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* http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt
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* for details. The code tries to filter out some of malicious packets.
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* Note that there is no way to be 100% secure.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: if_stf.c,v 1.36 2003/11/12 13:40:16 cl Exp $");
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#include "opt_inet.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/socket.h>
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#include <sys/sockio.h>
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#include <sys/mbuf.h>
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#include <sys/errno.h>
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#include <sys/ioctl.h>
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#include <sys/protosw.h>
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#include <sys/queue.h>
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#include <sys/syslog.h>
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#include <machine/cpu.h>
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#include <net/if.h>
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#include <net/route.h>
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#include <net/netisr.h>
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#include <net/if_types.h>
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#include <net/if_stf.h>
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/ip.h>
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#include <netinet/ip_var.h>
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#include <netinet/in_var.h>
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#include <netinet/ip6.h>
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#include <netinet6/ip6_var.h>
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#include <netinet6/in6_gif.h>
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#include <netinet6/in6_var.h>
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#include <netinet/ip_ecn.h>
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#include <netinet/ip_encap.h>
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#include <machine/stdarg.h>
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#include <net/net_osdep.h>
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#include "bpfilter.h"
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#include "stf.h"
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#include "gif.h" /*XXX*/
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#if NBPFILTER > 0
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#include <net/bpf.h>
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#endif
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#if NGIF > 0
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#include <net/if_gif.h>
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#endif
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#define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
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#define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1]))
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struct stf_softc {
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struct ifnet sc_if; /* common area */
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union {
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struct route __sc_ro4;
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struct route_in6 __sc_ro6; /* just for safety */
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} __sc_ro46;
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#define sc_ro __sc_ro46.__sc_ro4
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const struct encaptab *encap_cookie;
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LIST_ENTRY(stf_softc) sc_list;
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};
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LIST_HEAD(, stf_softc) stf_softc_list;
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int stf_clone_create __P((struct if_clone *, int));
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void stf_clone_destroy __P((struct ifnet *));
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struct if_clone stf_cloner =
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IF_CLONE_INITIALIZER("stf", stf_clone_create, stf_clone_destroy);
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#if NGIF > 0
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extern int ip_gif_ttl; /*XXX*/
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#else
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static int ip_gif_ttl = 40; /*XXX*/
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#endif
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extern struct domain inetdomain;
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struct protosw in_stf_protosw =
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{ SOCK_RAW, &inetdomain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR,
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in_stf_input, rip_output, 0, rip_ctloutput,
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rip_usrreq,
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0, 0, 0, 0
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};
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void stfattach __P((int));
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static int stf_encapcheck __P((const struct mbuf *, int, int, void *));
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static struct in6_ifaddr *stf_getsrcifa6 __P((struct ifnet *));
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static int stf_output __P((struct ifnet *, struct mbuf *, struct sockaddr *,
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struct rtentry *));
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static int isrfc1918addr __P((struct in_addr *));
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static int stf_checkaddr4 __P((struct stf_softc *, struct in_addr *,
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struct ifnet *));
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static int stf_checkaddr6 __P((struct stf_softc *, struct in6_addr *,
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struct ifnet *));
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static void stf_rtrequest __P((int, struct rtentry *, struct rt_addrinfo *));
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static int stf_ioctl __P((struct ifnet *, u_long, caddr_t));
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/* ARGSUSED */
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void
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stfattach(count)
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int count;
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{
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LIST_INIT(&stf_softc_list);
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if_clone_attach(&stf_cloner);
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}
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int
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stf_clone_create(ifc, unit)
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struct if_clone *ifc;
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int unit;
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{
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struct stf_softc *sc;
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if (LIST_FIRST(&stf_softc_list) != NULL) {
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/* Only one stf interface is allowed. */
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return (EEXIST);
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}
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sc = malloc(sizeof(struct stf_softc), M_DEVBUF, M_WAIT);
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memset(sc, 0, sizeof(struct stf_softc));
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sprintf(sc->sc_if.if_xname, "%s%d", ifc->ifc_name, unit);
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sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6,
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stf_encapcheck, &in_stf_protosw, sc);
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if (sc->encap_cookie == NULL) {
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printf("%s: unable to attach encap\n", if_name(&sc->sc_if));
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free(sc, M_DEVBUF);
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return (EIO); /* XXX */
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}
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sc->sc_if.if_mtu = IPV6_MMTU;
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sc->sc_if.if_flags = 0;
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sc->sc_if.if_ioctl = stf_ioctl;
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sc->sc_if.if_output = stf_output;
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sc->sc_if.if_type = IFT_STF;
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sc->sc_if.if_dlt = DLT_NULL;
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if_attach(&sc->sc_if);
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if_alloc_sadl(&sc->sc_if);
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#if NBPFILTER > 0
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bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int));
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#endif
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LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list);
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return (0);
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}
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void
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stf_clone_destroy(ifp)
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struct ifnet *ifp;
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{
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struct stf_softc *sc = (void *) ifp;
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LIST_REMOVE(sc, sc_list);
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encap_detach(sc->encap_cookie);
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#if NBPFILTER > 0
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bpfdetach(ifp);
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#endif
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if_detach(ifp);
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free(sc, M_DEVBUF);
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}
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static int
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stf_encapcheck(m, off, proto, arg)
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const struct mbuf *m;
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int off;
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int proto;
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void *arg;
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{
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struct ip ip;
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struct in6_ifaddr *ia6;
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struct stf_softc *sc;
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struct in_addr a, b;
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sc = (struct stf_softc *)arg;
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if (sc == NULL)
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return 0;
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if ((sc->sc_if.if_flags & IFF_UP) == 0)
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return 0;
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/* IFF_LINK0 means "no decapsulation" */
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if ((sc->sc_if.if_flags & IFF_LINK0) != 0)
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return 0;
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if (proto != IPPROTO_IPV6)
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return 0;
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/* LINTED const cast */
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m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip);
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if (ip.ip_v != 4)
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return 0;
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ia6 = stf_getsrcifa6(&sc->sc_if);
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if (ia6 == NULL)
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return 0;
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/*
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* check if IPv4 dst matches the IPv4 address derived from the
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* local 6to4 address.
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* success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:...
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*/
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if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst,
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sizeof(ip.ip_dst)) != 0)
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return 0;
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/*
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* check if IPv4 src matches the IPv4 address derived from the
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* local 6to4 address masked by prefixmask.
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* success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24
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* fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24
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*/
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memset(&a, 0, sizeof(a));
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a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr;
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a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
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b = ip.ip_src;
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b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
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if (a.s_addr != b.s_addr)
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return 0;
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/* stf interface makes single side match only */
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return 32;
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}
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static struct in6_ifaddr *
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stf_getsrcifa6(ifp)
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struct ifnet *ifp;
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{
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struct ifaddr *ia;
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struct in_ifaddr *ia4;
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struct sockaddr_in6 *sin6;
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struct in_addr in;
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TAILQ_FOREACH(ia, &ifp->if_addrlist, ifa_list)
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{
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if (ia->ifa_addr == NULL)
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continue;
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if (ia->ifa_addr->sa_family != AF_INET6)
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continue;
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sin6 = (struct sockaddr_in6 *)ia->ifa_addr;
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if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr))
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continue;
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bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in));
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INADDR_TO_IA(in, ia4);
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if (ia4 == NULL)
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continue;
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return (struct in6_ifaddr *)ia;
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}
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return NULL;
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}
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static int
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stf_output(ifp, m, dst, rt)
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struct ifnet *ifp;
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struct mbuf *m;
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struct sockaddr *dst;
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struct rtentry *rt;
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{
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struct stf_softc *sc;
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struct sockaddr_in6 *dst6;
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struct in_addr *in4;
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struct sockaddr_in *dst4;
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u_int8_t tos;
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struct ip *ip;
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struct ip6_hdr *ip6;
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struct in6_ifaddr *ia6;
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sc = (struct stf_softc*)ifp;
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dst6 = (struct sockaddr_in6 *)dst;
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/* just in case */
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if ((ifp->if_flags & IFF_UP) == 0) {
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m_freem(m);
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return ENETDOWN;
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}
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/*
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* If we don't have an ip4 address that match my inner ip6 address,
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* we shouldn't generate output. Without this check, we'll end up
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* using wrong IPv4 source.
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*/
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ia6 = stf_getsrcifa6(ifp);
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if (ia6 == NULL) {
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m_freem(m);
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ifp->if_oerrors++;
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return ENETDOWN;
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}
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if (m->m_len < sizeof(*ip6)) {
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m = m_pullup(m, sizeof(*ip6));
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if (m == NULL) {
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ifp->if_oerrors++;
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return ENOBUFS;
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}
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}
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ip6 = mtod(m, struct ip6_hdr *);
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tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
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/*
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* Pickup the right outer dst addr from the list of candidates.
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* ip6_dst has priority as it may be able to give us shorter IPv4 hops.
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*/
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if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst))
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in4 = GET_V4(&ip6->ip6_dst);
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else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr))
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in4 = GET_V4(&dst6->sin6_addr);
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else {
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m_freem(m);
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ifp->if_oerrors++;
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return ENETUNREACH;
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}
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#if NBPFILTER > 0
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if (ifp->if_bpf) {
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/*
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* We need to prepend the address family as
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* a four byte field. Cons up a dummy header
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* to pacify bpf. This is safe because bpf
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* will only read from the mbuf (i.e., it won't
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* try to free it or keep a pointer a to it).
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*/
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struct mbuf m0;
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u_int32_t af = AF_INET6;
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m0.m_flags = 0;
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m0.m_next = m;
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m0.m_len = 4;
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m0.m_data = (char *)⁡
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#ifdef HAVE_OLD_BPF
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bpf_mtap(ifp, &m0);
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#else
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bpf_mtap(ifp->if_bpf, &m0);
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#endif
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}
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#endif /*NBPFILTER > 0*/
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M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
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if (m && m->m_len < sizeof(struct ip))
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m = m_pullup(m, sizeof(struct ip));
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if (m == NULL) {
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ifp->if_oerrors++;
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return ENOBUFS;
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}
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ip = mtod(m, struct ip *);
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memset(ip, 0, sizeof(*ip));
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bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr),
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&ip->ip_src, sizeof(ip->ip_src));
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bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst));
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ip->ip_p = IPPROTO_IPV6;
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ip->ip_ttl = ip_gif_ttl; /*XXX*/
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ip->ip_len = htons(m->m_pkthdr.len);
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if (ifp->if_flags & IFF_LINK1)
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ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos);
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else
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ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos);
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dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst;
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if (dst4->sin_family != AF_INET ||
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bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) {
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/* cache route doesn't match */
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dst4->sin_family = AF_INET;
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dst4->sin_len = sizeof(struct sockaddr_in);
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bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr));
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if (sc->sc_ro.ro_rt) {
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RTFREE(sc->sc_ro.ro_rt);
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sc->sc_ro.ro_rt = NULL;
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}
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}
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if (sc->sc_ro.ro_rt == NULL) {
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rtalloc(&sc->sc_ro);
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if (sc->sc_ro.ro_rt == NULL) {
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m_freem(m);
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ifp->if_oerrors++;
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return ENETUNREACH;
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}
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}
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ifp->if_opackets++;
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return ip_output(m, NULL, &sc->sc_ro, 0,
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(struct ip_moptions *)NULL, (struct socket *)NULL);
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}
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static int
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isrfc1918addr(in)
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struct in_addr *in;
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{
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/*
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* returns 1 if private address range:
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* 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16
|
|
*/
|
|
if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 ||
|
|
(ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 ||
|
|
(ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
stf_checkaddr4(sc, in, inifp)
|
|
struct stf_softc *sc;
|
|
struct in_addr *in;
|
|
struct ifnet *inifp; /* incoming interface */
|
|
{
|
|
struct in_ifaddr *ia4;
|
|
|
|
/*
|
|
* reject packets with the following address:
|
|
* 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8
|
|
*/
|
|
if (IN_MULTICAST(in->s_addr))
|
|
return -1;
|
|
switch ((ntohl(in->s_addr) & 0xff000000) >> 24) {
|
|
case 0: case 127: case 255:
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* reject packets with private address range.
|
|
* (requirement from RFC3056 section 2 1st paragraph)
|
|
*/
|
|
if (isrfc1918addr(in))
|
|
return -1;
|
|
|
|
/*
|
|
* reject packet with IPv4 link-local (169.254.0.0/16),
|
|
* as suggested in draft-savola-v6ops-6to4-security-00.txt
|
|
*/
|
|
if (((ntohl(in->s_addr) & 0xff000000) >> 24) == 169 &&
|
|
((ntohl(in->s_addr) & 0x00ff0000) >> 16) == 254)
|
|
return -1;
|
|
|
|
/*
|
|
* reject packets with broadcast
|
|
*/
|
|
TAILQ_FOREACH(ia4, &in_ifaddrhead, ia_list)
|
|
{
|
|
if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
|
|
continue;
|
|
if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr)
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* perform ingress filter
|
|
*/
|
|
if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) {
|
|
struct sockaddr_in sin;
|
|
struct rtentry *rt;
|
|
|
|
memset(&sin, 0, sizeof(sin));
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_len = sizeof(struct sockaddr_in);
|
|
sin.sin_addr = *in;
|
|
rt = rtalloc1((struct sockaddr *)&sin, 0);
|
|
if (!rt || rt->rt_ifp != inifp) {
|
|
#if 0
|
|
log(LOG_WARNING, "%s: packet from 0x%x dropped "
|
|
"due to ingress filter\n", if_name(&sc->sc_if),
|
|
(u_int32_t)ntohl(sin.sin_addr.s_addr));
|
|
#endif
|
|
if (rt)
|
|
rtfree(rt);
|
|
return -1;
|
|
}
|
|
rtfree(rt);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
stf_checkaddr6(sc, in6, inifp)
|
|
struct stf_softc *sc;
|
|
struct in6_addr *in6;
|
|
struct ifnet *inifp; /* incoming interface */
|
|
{
|
|
|
|
/*
|
|
* check 6to4 addresses
|
|
*/
|
|
if (IN6_IS_ADDR_6TO4(in6))
|
|
return stf_checkaddr4(sc, GET_V4(in6), inifp);
|
|
|
|
/*
|
|
* reject anything that look suspicious. the test is implemented
|
|
* in ip6_input too, but we check here as well to
|
|
* (1) reject bad packets earlier, and
|
|
* (2) to be safe against future ip6_input change.
|
|
*/
|
|
if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6))
|
|
return -1;
|
|
|
|
/*
|
|
* reject link-local and site-local unicast
|
|
* as suggested in draft-savola-v6ops-6to4-security-00.txt
|
|
*/
|
|
if (IN6_IS_ADDR_LINKLOCAL(in6) || IN6_IS_ADDR_SITELOCAL(in6))
|
|
return -1;
|
|
|
|
/*
|
|
* reject node-local and link-local multicast
|
|
* as suggested in draft-savola-v6ops-6to4-security-00.txt
|
|
*/
|
|
if (IN6_IS_ADDR_MC_NODELOCAL(in6) || IN6_IS_ADDR_MC_LINKLOCAL(in6))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
#if __STDC__
|
|
in_stf_input(struct mbuf *m, ...)
|
|
#else
|
|
in_stf_input(m, va_alist)
|
|
struct mbuf *m;
|
|
#endif
|
|
{
|
|
int off, proto;
|
|
struct stf_softc *sc;
|
|
struct ip *ip;
|
|
struct ip6_hdr *ip6;
|
|
u_int8_t otos, itos;
|
|
int s, isr;
|
|
struct ifqueue *ifq = NULL;
|
|
struct ifnet *ifp;
|
|
va_list ap;
|
|
|
|
va_start(ap, m);
|
|
off = va_arg(ap, int);
|
|
proto = va_arg(ap, int);
|
|
va_end(ap);
|
|
|
|
if (proto != IPPROTO_IPV6) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
|
|
ip = mtod(m, struct ip *);
|
|
|
|
sc = (struct stf_softc *)encap_getarg(m);
|
|
|
|
if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
|
|
ifp = &sc->sc_if;
|
|
|
|
/*
|
|
* perform sanity check against outer src/dst.
|
|
* for source, perform ingress filter as well.
|
|
*/
|
|
if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 ||
|
|
stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
|
|
otos = ip->ip_tos;
|
|
m_adj(m, off);
|
|
|
|
if (m->m_len < sizeof(*ip6)) {
|
|
m = m_pullup(m, sizeof(*ip6));
|
|
if (!m)
|
|
return;
|
|
}
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
|
|
/*
|
|
* perform sanity check against inner src/dst.
|
|
* for source, perform ingress filter as well.
|
|
*/
|
|
if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 ||
|
|
stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
|
|
itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
|
|
if ((ifp->if_flags & IFF_LINK1) != 0)
|
|
ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
|
|
else
|
|
ip_ecn_egress(ECN_NOCARE, &otos, &itos);
|
|
ip6->ip6_flow &= ~htonl(0xff << 20);
|
|
ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
|
|
|
|
m->m_pkthdr.rcvif = ifp;
|
|
|
|
#if NBPFILTER > 0
|
|
if (ifp->if_bpf) {
|
|
/*
|
|
* We need to prepend the address family as
|
|
* a four byte field. Cons up a dummy header
|
|
* to pacify bpf. This is safe because bpf
|
|
* will only read from the mbuf (i.e., it won't
|
|
* try to free it or keep a pointer a to it).
|
|
*/
|
|
struct mbuf m0;
|
|
u_int32_t af = AF_INET6;
|
|
|
|
m0.m_flags = 0;
|
|
m0.m_next = m;
|
|
m0.m_len = 4;
|
|
m0.m_data = (char *)⁡
|
|
|
|
#ifdef HAVE_OLD_BPF
|
|
bpf_mtap(ifp, &m0);
|
|
#else
|
|
bpf_mtap(ifp->if_bpf, &m0);
|
|
#endif
|
|
}
|
|
#endif /*NBPFILTER > 0*/
|
|
|
|
/*
|
|
* Put the packet to the network layer input queue according to the
|
|
* specified address family.
|
|
* See net/if_gif.c for possible issues with packet processing
|
|
* reorder due to extra queueing.
|
|
*/
|
|
ifq = &ip6intrq;
|
|
isr = NETISR_IPV6;
|
|
|
|
s = splnet();
|
|
if (IF_QFULL(ifq)) {
|
|
IF_DROP(ifq); /* update statistics */
|
|
m_freem(m);
|
|
splx(s);
|
|
return;
|
|
}
|
|
IF_ENQUEUE(ifq, m);
|
|
schednetisr(isr);
|
|
ifp->if_ipackets++;
|
|
ifp->if_ibytes += m->m_pkthdr.len;
|
|
splx(s);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static void
|
|
stf_rtrequest(cmd, rt, info)
|
|
int cmd;
|
|
struct rtentry *rt;
|
|
struct rt_addrinfo *info;
|
|
{
|
|
|
|
if (rt)
|
|
rt->rt_rmx.rmx_mtu = IPV6_MMTU;
|
|
}
|
|
|
|
static int
|
|
stf_ioctl(ifp, cmd, data)
|
|
struct ifnet *ifp;
|
|
u_long cmd;
|
|
caddr_t data;
|
|
{
|
|
struct ifaddr *ifa;
|
|
struct ifreq *ifr;
|
|
struct sockaddr_in6 *sin6;
|
|
int error;
|
|
|
|
error = 0;
|
|
switch (cmd) {
|
|
case SIOCSIFADDR:
|
|
ifa = (struct ifaddr *)data;
|
|
if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) {
|
|
error = EAFNOSUPPORT;
|
|
break;
|
|
}
|
|
sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
|
|
if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr) &&
|
|
!isrfc1918addr(GET_V4(&sin6->sin6_addr))) {
|
|
ifa->ifa_rtrequest = stf_rtrequest;
|
|
ifp->if_flags |= IFF_UP;
|
|
} else
|
|
error = EINVAL;
|
|
break;
|
|
|
|
case SIOCADDMULTI:
|
|
case SIOCDELMULTI:
|
|
ifr = (struct ifreq *)data;
|
|
if (ifr && ifr->ifr_addr.sa_family == AF_INET6)
|
|
;
|
|
else
|
|
error = EAFNOSUPPORT;
|
|
break;
|
|
|
|
default:
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
|
|
return error;
|
|
}
|