1 /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi Exp $ */
4 * SPDX-License-Identifier: BSD-3-Clause
6 * Copyright (C) 2000 WIDE Project.
7 * Copyright (c) 2010 Hiroki Sato <hrs@FreeBSD.org>
8 * Copyright (c) 2013 Ermal Luci <eri@FreeBSD.org>
9 * Copyright (c) 2017-2021 Rubicon Communications, LLC (Netgate)
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the project nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * 6to4 interface, based on RFC3056.
40 * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting.
41 * There is no address mapping defined from IPv6 multicast address to IPv4
42 * address. Therefore, we do not have IFF_MULTICAST on the interface.
44 * Due to the lack of address mapping for link-local addresses, we cannot
45 * throw packets toward link-local addresses (fe80::x). Also, we cannot throw
46 * packets to link-local multicast addresses (ff02::x).
48 * Here are interesting symptoms due to the lack of link-local address:
50 * Unicast routing exchange:
51 * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9,
52 * and link-local addresses as nexthop.
53 * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address
54 * assigned to the link, and makes use of them. Also, HELLO packets use
55 * link-local multicast addresses (ff02::5 and ff02::6).
56 * - BGP4+: Maybe. You can only use global address as nexthop, and global
57 * address as TCP endpoint address.
59 * Multicast routing protocols:
60 * - PIM: Hello packet cannot be used to discover adjacent PIM routers.
61 * Adjacent PIM routers must be configured manually (is it really spec-wise
62 * correct thing to do?).
65 * - Redirects cannot be used due to the lack of link-local address.
67 * stf interface does not have, and will not need, a link-local address.
68 * It seems to have no real benefit and does not help the above symptoms much.
69 * Even if we assign link-locals to interface, we cannot really
70 * use link-local unicast/multicast on top of 6to4 cloud (since there's no
71 * encapsulation defined for link-local address), and the above analysis does
72 * not change. RFC3056 does not mandate the assignment of link-local address
75 * 6to4 interface has security issues. Refer to
76 * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt
77 * for details. The code tries to filter out some of malicious packets.
78 * Note that there is no way to be 100% secure.
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/socket.h>
84 #include <sys/sockio.h>
86 #include <sys/endian.h>
87 #include <sys/errno.h>
88 #include <sys/kernel.h>
90 #include <sys/module.h>
93 #include <sys/queue.h>
95 #include <sys/sysctl.h>
96 #include <machine/cpu.h>
98 #include <sys/malloc.h>
101 #include <net/if_var.h>
102 #include <net/if_private.h>
103 #include <net/if_clone.h>
104 #include <net/route.h>
105 #include <net/route/nhop.h>
106 #include <net/netisr.h>
107 #include <net/if_stf.h>
108 #include <net/if_types.h>
109 #include <net/vnet.h>
111 #include <netinet/in.h>
112 #include <netinet/in_fib.h>
113 #include <netinet/in_systm.h>
114 #include <netinet/ip.h>
115 #include <netinet/ip_var.h>
116 #include <netinet/in_var.h>
118 #include <netinet/ip6.h>
119 #include <netinet6/in6_fib.h>
120 #include <netinet6/ip6_var.h>
121 #include <netinet6/in6_var.h>
122 #include <netinet/ip_ecn.h>
124 #include <netinet/ip_encap.h>
126 #include <machine/stdarg.h>
130 #include <security/mac/mac_framework.h>
132 SDT_PROVIDER_DEFINE(if_stf);
133 SDT_PROBE_DEFINE3(if_stf, , encapcheck, in, "struct mbuf *", "int", "int");
134 SDT_PROBE_DEFINE0(if_stf, , encapcheck, accept);
135 SDT_PROBE_DEFINE3(if_stf, , getsrcifa6, in, "struct ifnet *",
136 "struct in6_addr *", "struct in6_addr *");
137 SDT_PROBE_DEFINE2(if_stf, , getsrcifa6, found, "struct in6_addr *",
138 "struct in6_addr *");
139 SDT_PROBE_DEFINE0(if_stf, , getsrcifa6, notfound);
141 SDT_PROBE_DEFINE4(if_stf, , stf_output, in, "struct ifnet *", "struct mbuf *",
142 "struct sockaddr *", "struct route *");
143 SDT_PROBE_DEFINE2(if_stf, , stf_output, error, "int", "int");
144 SDT_PROBE_DEFINE1(if_stf, , stf_output, out, "int");
146 SDT_PROBE_DEFINE3(if_stf, , checkaddr6, in, "struct stf_softc *",
147 "struct in6_addr *", "struct ifnet *");
148 SDT_PROBE_DEFINE2(if_stf, , checkaddr6, out, "int", "int");
150 SDT_PROBE_DEFINE3(if_stf, , stf_input, in, "struct mbuf *", "int", "int");
151 SDT_PROBE_DEFINE2(if_stf, , stf_input, out, "int", "int");
153 SDT_PROBE_DEFINE3(if_stf, , ioctl, sv4net, "struct in_addr *",
154 "struct in_addr *", "int");
155 SDT_PROBE_DEFINE1(if_stf, , ioctl, sdstv4, "struct in_addr *");
156 SDT_PROBE_DEFINE1(if_stf, , ioctl, ifaddr, "struct ifaddr *");
158 SDT_PROBE_DEFINE4(if_stf, , getin4addr_in6, out, "struct in6_addr *",
159 "struct in6_addr *", "struct in6_addr *", "struct sockaddr_in *");
161 SDT_PROBE_DEFINE2(if_stf, , getin4addr, in, "struct in6_addr *", "struct in6_addr *");
162 SDT_PROBE_DEFINE1(if_stf, , getin4addr, out, "struct sockaddr_in *");
164 SYSCTL_DECL(_net_link);
165 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
168 static int stf_permit_rfc1918 = 0;
169 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN,
170 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses");
174 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
177 * XXX: Return a pointer with 16-bit aligned. Don't cast it to
178 * struct in_addr *; use bcopy() instead.
180 #define GET_V4(x) (&(x)->s6_addr16[1])
183 struct ifnet *sc_ifp;
184 in_addr_t braddr; /* Border relay IPv4 address */
185 in_addr_t srcv4_addr; /* Our IPv4 WAN address */
186 u_int v4prefixlen; /* How much of the v4 address to include in our address. */
188 const struct encaptab *encap_cookie;
190 #define STF2IFP(sc) ((sc)->sc_ifp)
192 static const char stfname[] = "stf";
194 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface");
195 static const int ip_stf_ttl = 40;
197 static int in_stf_input(struct mbuf *, int, int, void *);
198 static char *stfnames[] = {"stf0", "stf", "6to4", NULL};
200 static int stfmodevent(module_t, int, void *);
201 static int stf_encapcheck(const struct mbuf *, int, int, void *);
202 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *);
203 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *,
205 static int isrfc1918addr(struct in_addr *);
206 static int stf_checkaddr4(struct stf_softc *, struct in_addr *,
208 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *,
210 static struct sockaddr_in *stf_getin4addr_in6(struct stf_softc *,
211 struct sockaddr_in *, struct in6_addr, struct in6_addr,
213 static struct sockaddr_in *stf_getin4addr(struct stf_softc *,
214 struct sockaddr_in *, struct in6_addr, struct in6_addr);
215 static int stf_ioctl(struct ifnet *, u_long, caddr_t);
217 VNET_DEFINE_STATIC(struct if_clone *, stf_cloner);
218 #define V_stf_cloner VNET(stf_cloner)
220 static const struct encap_config ipv4_encap_cfg = {
221 .proto = IPPROTO_IPV6,
222 .min_length = sizeof(struct ip),
223 .exact_match = (sizeof(in_addr_t) << 3) + 8,
224 .check = stf_encapcheck,
225 .input = in_stf_input
229 stf_clone_match(struct if_clone *ifc, const char *name)
233 for(i = 0; stfnames[i] != NULL; i++) {
234 if (strcmp(stfnames[i], name) == 0)
242 stf_clone_create(struct if_clone *ifc, char *name, size_t len,
243 struct ifc_data *ifd, struct ifnet **ifpp)
246 int err, unit, wildcard;
247 struct stf_softc *sc;
250 err = ifc_name2unit(name, &unit);
253 wildcard = (unit < 0);
256 * We can only have one unit, but since unit allocation is
257 * already locked, we use it to keep from allocating extra
261 err = ifc_alloc_unit(ifc, &unit);
265 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO);
266 ifp = STF2IFP(sc) = if_alloc(IFT_STF);
269 ifc_free_unit(ifc, unit);
273 sc->sc_fibnum = curthread->td_proc->p_fibnum;
276 * Set the name manually rather then using if_initname because
277 * we don't conform to the default naming convention for interfaces.
278 * In the wildcard case, we need to update the name.
281 for (dp = name; *dp != '\0'; dp++);
282 if (snprintf(dp, len - (dp-name), "%d", unit) >
283 len - (dp-name) - 1) {
285 * This can only be a programmer error and
286 * there's no straightforward way to recover if
289 panic("if_clone_create(): interface name too long");
292 strlcpy(ifp->if_xname, name, IFNAMSIZ);
293 ifp->if_dname = stfname;
294 ifp->if_dunit = IF_DUNIT_NONE;
296 sc->encap_cookie = ip_encap_attach(&ipv4_encap_cfg, sc, M_WAITOK);
298 ifp->if_mtu = IPV6_MMTU;
299 ifp->if_ioctl = stf_ioctl;
300 ifp->if_output = stf_output;
301 ifp->if_snd.ifq_maxlen = ifqmaxlen;
303 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
310 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags)
312 struct stf_softc *sc = ifp->if_softc;
315 err = ip_encap_detach(sc->encap_cookie);
316 KASSERT(err == 0, ("Unexpected error detaching encap_cookie"));
322 ifc_free_unit(ifc, STFUNIT);
328 vnet_stf_init(const void *unused __unused)
330 struct if_clone_addreq req = {
331 .match_f = stf_clone_match,
332 .create_f = stf_clone_create,
333 .destroy_f = stf_clone_destroy,
335 V_stf_cloner = ifc_attach_cloner(stfname, &req);
337 VNET_SYSINIT(vnet_stf_init, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_stf_init, NULL);
340 vnet_stf_uninit(const void *unused __unused)
342 if_clone_detach(V_stf_cloner);
345 VNET_SYSUNINIT(vnet_stf_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_stf_uninit,
349 stfmodevent(module_t mod, int type, void *data)
354 /* Done in vnet_stf_init() */
357 /* Done in vnet_stf_uninit() */
366 static moduledata_t stf_mod = {
372 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
373 MODULE_VERSION(if_stf, 2);
376 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
379 struct stf_softc *sc;
380 struct in6_addr addr6, mask6;
381 struct sockaddr_in sin4addr, sin4mask;
383 SDT_PROBE3(if_stf, , encapcheck, in, m, off, proto);
385 sc = (struct stf_softc *)arg;
389 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0)
392 /* IFF_LINK0 means "no decapsulation" */
393 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0)
396 if (proto != IPPROTO_IPV6)
399 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
404 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0)
407 if (sc->srcv4_addr != INADDR_ANY) {
408 sin4addr.sin_addr.s_addr = sc->srcv4_addr;
409 sin4addr.sin_family = AF_INET;
411 if (stf_getin4addr(sc, &sin4addr, addr6, mask6) == NULL)
414 if (sin4addr.sin_addr.s_addr != ip.ip_dst.s_addr)
417 if (IN6_IS_ADDR_6TO4(&addr6)) {
420 * Check if IPv4 src matches the IPv4 address derived
421 * from the local 6to4 address masked by prefixmask.
422 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24
423 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24
425 memcpy(&sin4mask.sin_addr, GET_V4(&mask6),
426 sizeof(sin4mask.sin_addr));
427 if ((sin4addr.sin_addr.s_addr & sin4mask.sin_addr.s_addr) !=
428 (ip.ip_src.s_addr & sin4mask.sin_addr.s_addr))
433 * No restriction on the src address in the case of
434 * 6rd because the stf(4) interface always has a
435 * prefix which covers whole of IPv4 src address
436 * range. So, stf_output() will catch all of
437 * 6rd-capsuled IPv4 traffic with suspicious inner dst
438 * IPv4 address (i.e. the IPv6 destination address is
439 * one the admin does not like to route to outside),
440 * and then it discard them silently.
444 SDT_PROBE0(if_stf, , encapcheck, accept);
446 /* stf interface makes single side match only */
451 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask)
454 struct in_ifaddr *ia4;
455 struct in6_addr addr6, mask6;
456 struct sockaddr_in sin4;
457 struct stf_softc *sc;
464 SDT_PROBE3(if_stf, , getsrcifa6, in, ifp, addr, mask);
466 CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) {
467 if (ia->ifa_addr->sa_family != AF_INET6)
470 addr6 = *IFA_IN6(ia);
471 mask6 = *IFA_MASKIN6(ia);
472 if (sc->srcv4_addr != INADDR_ANY)
473 bcopy(&sc->srcv4_addr, &in, sizeof(in));
475 if (stf_getin4addr(sc, &sin4, addr6, mask6) == NULL)
477 bcopy(&sin4.sin_addr, &in, sizeof(in));
480 CK_LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash)
481 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr)
489 SDT_PROBE2(if_stf, , getsrcifa6, found, addr, mask);
494 SDT_PROBE0(if_stf, , getsrcifa6, notfound);
500 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
503 struct stf_softc *sc;
504 const struct sockaddr_in6 *dst6;
505 struct sockaddr_in dst4, src4;
509 struct in6_addr addr6, mask6;
512 SDT_PROBE4(if_stf, , stf_output, in, ifp, m, dst, ro);
515 error = mac_ifnet_check_transmit(ifp, m);
518 SDT_PROBE2(if_stf, , stf_output, error, error, __LINE__);
524 dst6 = (const struct sockaddr_in6 *)dst;
527 if ((ifp->if_flags & IFF_UP) == 0) {
529 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
530 SDT_PROBE2(if_stf, , stf_output, error, ENETDOWN, __LINE__);
535 * If we don't have an ip4 address that match my inner ip6 address,
536 * we shouldn't generate output. Without this check, we'll end up
537 * using wrong IPv4 source.
539 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) {
541 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
542 SDT_PROBE2(if_stf, , stf_output, error, ENETDOWN, __LINE__);
546 if (m->m_len < sizeof(*ip6)) {
547 m = m_pullup(m, sizeof(*ip6));
549 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
550 SDT_PROBE2(if_stf, , stf_output, error, ENOBUFS,
555 ip6 = mtod(m, struct ip6_hdr *);
556 tos = IPV6_TRAFFIC_CLASS(ip6);
559 * Pickup the right outer dst addr from the list of candidates.
560 * ip6_dst has priority as it may be able to give us shorter IPv4 hops.
562 if (stf_getin4addr_in6(sc, &dst4, addr6, mask6,
563 ip6->ip6_dst) == NULL) {
564 if (sc->braddr != INADDR_ANY)
565 dst4.sin_addr.s_addr = sc->braddr;
566 else if (stf_getin4addr_in6(sc, &dst4, addr6, mask6,
567 dst6->sin6_addr) == NULL) {
569 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
570 SDT_PROBE2(if_stf, , stf_output, error, ENETUNREACH,
572 return (ENETUNREACH);
576 if (bpf_peers_present(ifp->if_bpf)) {
578 * We need to prepend the address family as
579 * a four byte field. Cons up a dummy header
580 * to pacify bpf. This is safe because bpf
581 * will only read from the mbuf (i.e., it won't
582 * try to free it or keep a pointer a to it).
585 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
588 M_PREPEND(m, sizeof(struct ip), M_NOWAIT);
590 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
591 SDT_PROBE2(if_stf, , stf_output, error, ENOBUFS, __LINE__);
594 ip = mtod(m, struct ip *);
596 bzero(ip, sizeof(*ip));
598 if (sc->srcv4_addr != INADDR_ANY)
599 src4.sin_addr.s_addr = sc->srcv4_addr;
600 else if (stf_getin4addr(sc, &src4, addr6, mask6) == NULL) {
602 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
603 SDT_PROBE2(if_stf, , stf_output, error, ENETUNREACH, __LINE__);
604 return (ENETUNREACH);
606 bcopy(&src4.sin_addr, &ip->ip_src, sizeof(ip->ip_src));
607 bcopy(&dst4.sin_addr, &ip->ip_dst, sizeof(ip->ip_dst));
609 ip->ip_p = IPPROTO_IPV6;
610 ip->ip_ttl = ip_stf_ttl;
611 ip->ip_len = htons(m->m_pkthdr.len);
612 if (ifp->if_flags & IFF_LINK1)
613 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos);
615 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos);
617 M_SETFIB(m, sc->sc_fibnum);
618 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
619 error = ip_output(m, NULL, NULL, 0, NULL, NULL);
621 SDT_PROBE1(if_stf, , stf_output, out, error);
626 isrfc1918addr(struct in_addr *in)
629 * returns 1 if private address range:
630 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16
632 if (stf_permit_rfc1918 == 0 && (
633 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 ||
634 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 ||
635 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168))
642 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp)
644 struct in_ifaddr *ia4;
647 * reject packets with the following address:
648 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8
650 if (IN_MULTICAST(ntohl(in->s_addr)))
652 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) {
653 case 0: case 127: case 255:
658 * reject packets with broadcast
660 CK_STAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) {
661 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
663 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) {
669 * perform ingress filter
671 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) {
672 struct nhop_object *nh;
675 nh = fib4_lookup(sc->sc_fibnum, *in, 0, 0, 0);
679 if (nh->nh_ifp != inifp)
687 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp)
689 SDT_PROBE3(if_stf, , checkaddr6, in, sc, in6, inifp);
692 * check 6to4 addresses
694 if (IN6_IS_ADDR_6TO4(in6)) {
698 bcopy(GET_V4(in6), &in4, sizeof(in4));
699 ret = stf_checkaddr4(sc, &in4, inifp);
700 SDT_PROBE2(if_stf, , checkaddr6, out, ret, __LINE__);
705 * reject anything that look suspicious. the test is implemented
706 * in ip6_input too, but we check here as well to
707 * (1) reject bad packets earlier, and
708 * (2) to be safe against future ip6_input change.
710 if (IN6_IS_ADDR_V4COMPAT(in6)) {
711 SDT_PROBE2(if_stf, , checkaddr6, out, -1, __LINE__);
715 if (IN6_IS_ADDR_V4MAPPED(in6)) {
716 SDT_PROBE2(if_stf, , checkaddr6, out, -1, __LINE__);
720 SDT_PROBE2(if_stf, , checkaddr6, out, 0, __LINE__);
725 in_stf_input(struct mbuf *m, int off, int proto, void *arg)
727 struct stf_softc *sc = arg;
732 struct nhop_object *nh;
736 SDT_PROBE3(if_stf, , stf_input, in, m, off, proto);
738 if (proto != IPPROTO_IPV6) {
740 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
741 return (IPPROTO_DONE);
744 m_copydata(m, 0, sizeof(struct ip), (caddr_t)&ip);
745 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) {
747 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
748 return (IPPROTO_DONE);
754 mac_ifnet_create_mbuf(ifp, m);
758 * perform sanity check against outer src/dst.
759 * for source, perform ingress filter as well.
761 if (stf_checkaddr4(sc, &ip.ip_dst, NULL) < 0 ||
762 stf_checkaddr4(sc, &ip.ip_src, m->m_pkthdr.rcvif) < 0) {
764 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
765 return (IPPROTO_DONE);
771 if (m->m_len < sizeof(*ip6)) {
772 m = m_pullup(m, sizeof(*ip6));
774 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE,
776 return (IPPROTO_DONE);
779 ip6 = mtod(m, struct ip6_hdr *);
782 * perform sanity check against inner src/dst.
783 * for source, perform ingress filter as well.
785 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 ||
786 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) {
788 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
789 return (IPPROTO_DONE);
793 * reject packets with private address range.
794 * (requirement from RFC3056 section 2 1st paragraph)
796 if ((IN6_IS_ADDR_6TO4(&ip6->ip6_src) && isrfc1918addr(&ip.ip_src)) ||
797 (IN6_IS_ADDR_6TO4(&ip6->ip6_dst) && isrfc1918addr(&ip.ip_dst))) {
799 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
800 return (IPPROTO_DONE);
804 * Ignore if the destination is the same stf interface because
805 * all of valid IPv6 outgoing traffic should go interfaces
808 nh = fib6_lookup(sc->sc_fibnum, &ip6->ip6_dst, 0, 0, 0);
811 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
812 return (IPPROTO_DONE);
814 if ((nh->nh_ifp == ifp) &&
815 (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, &nh->gw6_sa.sin6_addr))) {
817 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
818 return (IPPROTO_DONE);
821 itos = IPV6_TRAFFIC_CLASS(ip6);
822 if ((ifp->if_flags & IFF_LINK1) != 0)
823 ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
825 ip_ecn_egress(ECN_NOCARE, &otos, &itos);
826 ip6->ip6_flow &= ~htonl(0xff << 20);
827 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
829 m->m_pkthdr.rcvif = ifp;
831 if (bpf_peers_present(ifp->if_bpf)) {
833 * We need to prepend the address family as
834 * a four byte field. Cons up a dummy header
835 * to pacify bpf. This is safe because bpf
836 * will only read from the mbuf (i.e., it won't
837 * try to free it or keep a pointer a to it).
839 u_int32_t af = AF_INET6;
840 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
844 * Put the packet to the network layer input queue according to the
845 * specified address family.
846 * See net/if_gif.c for possible issues with packet processing
847 * reorder due to extra queueing.
849 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
850 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len);
851 M_SETFIB(m, ifp->if_fib);
852 netisr_dispatch(NETISR_IPV6, m);
853 SDT_PROBE2(if_stf, , stf_input, out, IPPROTO_DONE, __LINE__);
854 return (IPPROTO_DONE);
857 static struct sockaddr_in *
858 stf_getin4addr_in6(struct stf_softc *sc, struct sockaddr_in *sin,
859 struct in6_addr addr6, struct in6_addr mask6, struct in6_addr in6)
862 struct sockaddr_in *out;
865 * When (src addr & src mask) != (in6 & src mask),
866 * the dst is not in the 6rd domain. The IPv4 address must
869 for (i = 0; i < sizeof(addr6); i++) {
870 if ((((u_char *)&addr6)[i] & ((u_char *)&mask6)[i]) !=
871 (((u_char *)&in6)[i] & ((u_char *)&mask6)[i])) {
872 SDT_PROBE4(if_stf, , getin4addr_in6, out, &addr6,
878 /* After the mask check, use in6 instead of addr6. */
879 out = stf_getin4addr(sc, sin, in6, mask6);
880 SDT_PROBE4(if_stf, , getin4addr_in6, out, &addr6, &mask6, &in6, out);
884 static struct sockaddr_in *
885 stf_getin4addr(struct stf_softc *sc, struct sockaddr_in *sin,
886 struct in6_addr addr6, struct in6_addr mask6)
890 SDT_PROBE2(if_stf, , getin4addr, in, &addr6, &mask6);
892 memset(sin, 0, sizeof(*sin));
894 if (IN6_IS_ADDR_6TO4(&addr6)) {
895 /* 6to4 (RFC 3056) */
896 bcopy(GET_V4(&addr6), in, sizeof(*in));
897 if (isrfc1918addr(in))
902 uint8_t *v6 = (uint8_t*)&addr6;
908 if (sc->v4prefixlen < 32) {
909 v4suffixlen = 32 - sc->v4prefixlen;
910 v4prefix = ntohl(sc->srcv4_addr) &
911 (0xffffffffU << v4suffixlen);
913 MPASS(sc->v4prefixlen == 32);
917 plen = in6_mask2len(&mask6, NULL);
921 /* To make this simple we do not support prefixes longer than
922 * 64 bits. RFC5969 says "a 6rd delegated prefix SHOULD be /64
923 * or shorter." so this is a moderately safe assumption. */
924 v6prefix = be64toh(*(uint64_t *)v6);
926 /* Shift away the v6 prefix itself. */
930 /* Now shift away everything after the v4 address. */
931 v6prefix >>= 64 - plen - v4suffixlen;
933 sin->sin_addr.s_addr = htonl(v4prefix | (uint32_t)v6prefix);
936 SDT_PROBE1(if_stf, , getin4addr, out, sin);
942 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
947 struct sockaddr_in sin4;
948 struct stf_softc *sc_cur;
949 struct stfv4args args;
953 sc_cur = ifp->if_softc;
957 ifd = (struct ifdrv *)data;
958 error = priv_check(curthread, PRIV_NET_ADDIFADDR);
961 if (ifd->ifd_cmd == STF6RD_SV4NET) {
962 if (ifd->ifd_len != sizeof(args)) {
966 bzero(&args, sizeof(args));
967 error = copyin(ifd->ifd_data, &args, ifd->ifd_len);
971 if (args.v4_prefixlen < 1 || args.v4_prefixlen > 32) {
976 bcopy(&args.srcv4_addr, &sc_cur->srcv4_addr,
977 sizeof(sc_cur->srcv4_addr));
978 sc_cur->v4prefixlen = args.v4_prefixlen;
979 SDT_PROBE3(if_stf, , ioctl, sv4net, sc_cur->srcv4_addr,
980 sc_cur->srcv4_addr, sc_cur->v4prefixlen);
981 } else if (ifd->ifd_cmd == STF6RD_SBR) {
982 if (ifd->ifd_len != sizeof(args)) {
986 bzero(&args, sizeof(args));
987 error = copyin(ifd->ifd_data, &args, ifd->ifd_len);
990 sc_cur->braddr = args.braddr.s_addr;
991 SDT_PROBE1(if_stf, , ioctl, sdstv4,
997 ifd = (struct ifdrv *)data;
998 if (ifd->ifd_cmd != STF6RD_GV4NET) {
1002 if (ifd->ifd_len != sizeof(args)) {
1006 bzero(&args, sizeof(args));
1007 args.srcv4_addr.s_addr = sc_cur->srcv4_addr;
1008 args.braddr.s_addr = sc_cur->braddr;
1009 args.v4_prefixlen = sc_cur->v4prefixlen;
1010 error = copyout(&args, ifd->ifd_data, ifd->ifd_len);
1013 ifa = (struct ifaddr *)data;
1014 SDT_PROBE1(if_stf, , ioctl, ifaddr, ifa);
1015 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) {
1016 error = EAFNOSUPPORT;
1019 if (stf_getin4addr(sc_cur, &sin4,
1020 satosin6(ifa->ifa_addr)->sin6_addr,
1021 satosin6(ifa->ifa_netmask)->sin6_addr) == NULL) {
1025 ifp->if_flags |= IFF_UP;
1026 ifp->if_drv_flags |= IFF_DRV_RUNNING;
1031 ifr = (struct ifreq *)data;
1032 if (ifr && ifr->ifr_addr.sa_family == AF_INET6)
1035 error = EAFNOSUPPORT;
1042 ifr = (struct ifreq *)data;
1044 /* RFC 4213 3.2 ideal world MTU */
1045 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20)