2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * Copyright (c) 2018 Andrey V. Elsukov <ae@FreeBSD.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
39 #include "opt_inet6.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
44 #include <sys/socket.h>
45 #include <sys/sockio.h>
47 #include <sys/errno.h>
48 #include <sys/kernel.h>
49 #include <sys/syslog.h>
50 #include <sys/sysctl.h>
51 #include <sys/malloc.h>
54 #include <net/ethernet.h>
56 #include <net/if_var.h>
57 #include <net/route.h>
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #include <netinet/ip_ecn.h>
66 #include <netinet/ip_encap.h>
67 #include <netinet/ip6.h>
68 #include <netinet6/ip6_var.h>
69 #include <netinet6/in6_var.h>
70 #include <netinet6/scope6_var.h>
71 #include <netinet6/ip6_ecn.h>
72 #include <netinet6/in6_fib.h>
74 #include <net/if_gif.h>
77 VNET_DEFINE_STATIC(int, ip6_gif_hlim) = GIF_HLIM;
78 #define V_ip6_gif_hlim VNET(ip6_gif_hlim)
80 SYSCTL_DECL(_net_inet6_ip6);
81 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim,
82 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_gif_hlim), 0,
83 "Default hop limit for encapsulated packets");
86 * We keep interfaces in a hash table using src+dst as key.
87 * Interfaces with GIF_IGNORE_SOURCE flag are linked into plain list.
89 VNET_DEFINE_STATIC(struct gif_list *, ipv6_hashtbl) = NULL;
90 VNET_DEFINE_STATIC(struct gif_list *, ipv6_srchashtbl) = NULL;
91 VNET_DEFINE_STATIC(struct gif_list, ipv6_list) = CK_LIST_HEAD_INITIALIZER();
92 #define V_ipv6_hashtbl VNET(ipv6_hashtbl)
93 #define V_ipv6_srchashtbl VNET(ipv6_srchashtbl)
94 #define V_ipv6_list VNET(ipv6_list)
96 #define GIF_HASH(src, dst) (V_ipv6_hashtbl[\
97 in6_gif_hashval((src), (dst)) & (GIF_HASH_SIZE - 1)])
98 #define GIF_SRCHASH(src) (V_ipv6_srchashtbl[\
99 fnv_32_buf((src), sizeof(*src), FNV1_32_INIT) & (GIF_HASH_SIZE - 1)])
100 #define GIF_HASH_SC(sc) GIF_HASH(&(sc)->gif_ip6hdr->ip6_src,\
101 &(sc)->gif_ip6hdr->ip6_dst)
103 in6_gif_hashval(const struct in6_addr *src, const struct in6_addr *dst)
107 ret = fnv_32_buf(src, sizeof(*src), FNV1_32_INIT);
108 return (fnv_32_buf(dst, sizeof(*dst), ret));
112 in6_gif_checkdup(const struct gif_softc *sc, const struct in6_addr *src,
113 const struct in6_addr *dst)
115 struct gif_softc *tmp;
117 if (sc->gif_family == AF_INET6 &&
118 IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src, src) &&
119 IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst, dst))
122 CK_LIST_FOREACH(tmp, &GIF_HASH(src, dst), chain) {
125 if (IN6_ARE_ADDR_EQUAL(&tmp->gif_ip6hdr->ip6_src, src) &&
126 IN6_ARE_ADDR_EQUAL(&tmp->gif_ip6hdr->ip6_dst, dst))
127 return (EADDRNOTAVAIL);
133 * Check that ingress address belongs to local host.
136 in6_gif_set_running(struct gif_softc *sc)
139 if (in6_localip(&sc->gif_ip6hdr->ip6_src))
140 GIF2IFP(sc)->if_drv_flags |= IFF_DRV_RUNNING;
142 GIF2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
146 * ifaddr_event handler.
147 * Clear IFF_DRV_RUNNING flag when ingress address disappears to prevent
148 * source address spoofing.
151 in6_gif_srcaddr(void *arg __unused, const struct sockaddr *sa, int event)
153 const struct sockaddr_in6 *sin;
154 struct gif_softc *sc;
156 /* Check that VNET is ready */
157 if (V_ipv6_hashtbl == NULL)
161 sin = (const struct sockaddr_in6 *)sa;
162 CK_LIST_FOREACH(sc, &GIF_SRCHASH(&sin->sin6_addr), srchash) {
163 if (IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src,
164 &sin->sin6_addr) == 0)
166 in6_gif_set_running(sc);
171 in6_gif_attach(struct gif_softc *sc)
174 if (sc->gif_options & GIF_IGNORE_SOURCE)
175 CK_LIST_INSERT_HEAD(&V_ipv6_list, sc, chain);
177 CK_LIST_INSERT_HEAD(&GIF_HASH_SC(sc), sc, chain);
179 CK_LIST_INSERT_HEAD(&GIF_SRCHASH(&sc->gif_ip6hdr->ip6_src),
184 in6_gif_setopts(struct gif_softc *sc, u_int options)
187 /* NOTE: we are protected with gif_ioctl_sx lock */
188 MPASS(sc->gif_family == AF_INET6);
189 MPASS(sc->gif_options != options);
191 if ((options & GIF_IGNORE_SOURCE) !=
192 (sc->gif_options & GIF_IGNORE_SOURCE)) {
193 CK_LIST_REMOVE(sc, srchash);
194 CK_LIST_REMOVE(sc, chain);
195 sc->gif_options = options;
202 in6_gif_ioctl(struct gif_softc *sc, u_long cmd, caddr_t data)
204 struct in6_ifreq *ifr = (struct in6_ifreq *)data;
205 struct sockaddr_in6 *dst, *src;
209 /* NOTE: we are protected with gif_ioctl_sx lock */
212 case SIOCSIFPHYADDR_IN6:
213 src = &((struct in6_aliasreq *)data)->ifra_addr;
214 dst = &((struct in6_aliasreq *)data)->ifra_dstaddr;
217 if (src->sin6_family != dst->sin6_family ||
218 src->sin6_family != AF_INET6 ||
219 src->sin6_len != dst->sin6_len ||
220 src->sin6_len != sizeof(*src))
222 if (IN6_IS_ADDR_UNSPECIFIED(&src->sin6_addr) ||
223 IN6_IS_ADDR_UNSPECIFIED(&dst->sin6_addr)) {
224 error = EADDRNOTAVAIL;
228 * Check validity of the scope zone ID of the
229 * addresses, and convert it into the kernel
230 * internal form if necessary.
232 if ((error = sa6_embedscope(src, 0)) != 0 ||
233 (error = sa6_embedscope(dst, 0)) != 0)
236 if (V_ipv6_hashtbl == NULL) {
237 V_ipv6_hashtbl = gif_hashinit();
238 V_ipv6_srchashtbl = gif_hashinit();
240 error = in6_gif_checkdup(sc, &src->sin6_addr,
242 if (error == EADDRNOTAVAIL)
244 if (error == EEXIST) {
245 /* Addresses are the same. Just return. */
249 ip6 = malloc(sizeof(*ip6), M_GIF, M_WAITOK | M_ZERO);
250 ip6->ip6_src = src->sin6_addr;
251 ip6->ip6_dst = dst->sin6_addr;
252 ip6->ip6_vfc = IPV6_VERSION;
253 if (sc->gif_family != 0) {
254 /* Detach existing tunnel first */
255 CK_LIST_REMOVE(sc, srchash);
256 CK_LIST_REMOVE(sc, chain);
258 free(sc->gif_hdr, M_GIF);
259 /* XXX: should we notify about link state change? */
261 sc->gif_family = AF_INET6;
262 sc->gif_ip6hdr = ip6;
264 in6_gif_set_running(sc);
266 case SIOCGIFPSRCADDR_IN6:
267 case SIOCGIFPDSTADDR_IN6:
268 if (sc->gif_family != AF_INET6) {
269 error = EADDRNOTAVAIL;
272 src = (struct sockaddr_in6 *)&ifr->ifr_addr;
273 memset(src, 0, sizeof(*src));
274 src->sin6_family = AF_INET6;
275 src->sin6_len = sizeof(*src);
276 src->sin6_addr = (cmd == SIOCGIFPSRCADDR_IN6) ?
277 sc->gif_ip6hdr->ip6_src: sc->gif_ip6hdr->ip6_dst;
278 error = prison_if(curthread->td_ucred, (struct sockaddr *)src);
280 error = sa6_recoverscope(src);
282 memset(src, 0, sizeof(*src));
289 in6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn)
291 struct gif_softc *sc = ifp->if_softc;
295 /* prepend new IP header */
297 len = sizeof(struct ip6_hdr);
298 #ifndef __NO_STRICT_ALIGNMENT
299 if (proto == IPPROTO_ETHERIP)
300 len += ETHERIP_ALIGN;
302 M_PREPEND(m, len, M_NOWAIT);
305 #ifndef __NO_STRICT_ALIGNMENT
306 if (proto == IPPROTO_ETHERIP) {
307 len = mtod(m, vm_offset_t) & 3;
308 KASSERT(len == 0 || len == ETHERIP_ALIGN,
309 ("in6_gif_output: unexpected misalignment"));
311 m->m_len -= ETHERIP_ALIGN;
315 ip6 = mtod(m, struct ip6_hdr *);
316 MPASS(sc->gif_family == AF_INET6);
317 bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr));
319 ip6->ip6_flow |= htonl((uint32_t)ecn << 20);
320 ip6->ip6_nxt = proto;
321 ip6->ip6_hlim = V_ip6_gif_hlim;
323 * force fragmentation to minimum MTU, to avoid path MTU discovery.
324 * it is too painful to ask for resend of inner packet, to achieve
325 * path MTU discovery for encapsulated packets.
327 return (ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL));
331 in6_gif_input(struct mbuf *m, int off, int proto, void *arg)
333 struct gif_softc *sc = arg;
341 IP6STAT_INC(ip6s_nogif);
342 return (IPPROTO_DONE);
345 if ((gifp->if_flags & IFF_UP) != 0) {
346 ip6 = mtod(m, struct ip6_hdr *);
347 ecn = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
349 gif_input(m, gifp, proto, ecn);
352 IP6STAT_INC(ip6s_nogif);
354 return (IPPROTO_DONE);
358 in6_gif_lookup(const struct mbuf *m, int off, int proto, void **arg)
360 const struct ip6_hdr *ip6;
361 struct gif_softc *sc;
364 if (V_ipv6_hashtbl == NULL)
369 * NOTE: it is safe to iterate without any locking here, because softc
370 * can be reclaimed only when we are not within net_epoch_preempt
371 * section, but ip_encap lookup+input are executed in epoch section.
373 ip6 = mtod(m, const struct ip6_hdr *);
375 CK_LIST_FOREACH(sc, &GIF_HASH(&ip6->ip6_dst, &ip6->ip6_src), chain) {
377 * This is an inbound packet, its ip6_dst is source address
380 if (IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src,
382 IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst,
384 ret = ENCAP_DRV_LOOKUP;
390 * Check the list of interfaces with GIF_IGNORE_SOURCE flag.
392 CK_LIST_FOREACH(sc, &V_ipv6_list, chain) {
393 if (IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src,
395 ret = 128 + 8; /* src + proto */
401 if ((GIF2IFP(sc)->if_flags & IFF_UP) == 0)
403 /* ingress filters on outer source */
404 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0) {
405 if (fib6_check_urpf(sc->gif_fibnum, &ip6->ip6_src,
406 ntohs(in6_getscope(&ip6->ip6_src)), NHR_NONE,
407 m->m_pkthdr.rcvif) == 0)
414 static const struct srcaddrtab *ipv6_srcaddrtab;
416 const struct encap_config encap;
417 const struct encaptab *cookie;
418 } ipv6_encap_cfg[] = {
422 .proto = IPPROTO_IPV4,
423 .min_length = sizeof(struct ip6_hdr) +
425 .exact_match = ENCAP_DRV_LOOKUP,
426 .lookup = in6_gif_lookup,
427 .input = in6_gif_input
433 .proto = IPPROTO_IPV6,
434 .min_length = 2 * sizeof(struct ip6_hdr),
435 .exact_match = ENCAP_DRV_LOOKUP,
436 .lookup = in6_gif_lookup,
437 .input = in6_gif_input
442 .proto = IPPROTO_ETHERIP,
443 .min_length = sizeof(struct ip6_hdr) +
444 sizeof(struct etherip_header) +
445 sizeof(struct ether_header),
446 .exact_match = ENCAP_DRV_LOOKUP,
447 .lookup = in6_gif_lookup,
448 .input = in6_gif_input
458 if (!IS_DEFAULT_VNET(curvnet))
461 ipv6_srcaddrtab = ip6_encap_register_srcaddr(in6_gif_srcaddr,
463 for (i = 0; i < nitems(ipv6_encap_cfg); i++)
464 ipv6_encap_cfg[i].cookie = ip6_encap_attach(
465 &ipv6_encap_cfg[i].encap, NULL, M_WAITOK);
473 if (IS_DEFAULT_VNET(curvnet)) {
474 for (i = 0; i < nitems(ipv6_encap_cfg); i++)
475 ip6_encap_detach(ipv6_encap_cfg[i].cookie);
476 ip6_encap_unregister_srcaddr(ipv6_srcaddrtab);
478 if (V_ipv6_hashtbl != NULL) {
479 gif_hashdestroy(V_ipv6_hashtbl);
480 V_ipv6_hashtbl = NULL;
482 gif_hashdestroy(V_ipv6_srchashtbl);