2 * Copyright (C)2003-2006 Helsinki University of Technology
3 * Copyright (C)2003-2006 USAGI/WIDE Project
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 * Noriaki TAKAMIYA @USAGI
21 * Masahide NAKAMURA @USAGI
24 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
26 #include <linux/module.h>
27 #include <linux/skbuff.h>
28 #include <linux/time.h>
29 #include <linux/ipv6.h>
30 #include <linux/icmpv6.h>
33 #include <net/ip6_checksum.h>
34 #include <net/rawv6.h>
38 static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
40 return (n - len + 16) & 0x7;
43 static inline void *mip6_padn(__u8 *data, __u8 padlen)
48 data[0] = IPV6_TLV_PAD1;
49 } else if (padlen > 1) {
50 data[0] = IPV6_TLV_PADN;
53 memset(data+2, 0, data[1]);
58 static inline void mip6_param_prob(struct sk_buff *skb, u8 code, int pos)
60 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
63 static int mip6_mh_len(int type)
71 case IP6_MH_TYPE_HOTI:
72 case IP6_MH_TYPE_COTI:
74 case IP6_MH_TYPE_BACK:
79 case IP6_MH_TYPE_BERROR:
86 static int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
89 const struct ip6_mh *mh;
91 mh = skb_header_pointer(skb, skb_transport_offset(skb),
96 if (((mh->ip6mh_hdrlen + 1) << 3) > skb->len)
99 if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
100 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
101 mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
102 mip6_param_prob(skb, 0, offsetof(struct ip6_mh, ip6mh_hdrlen) +
103 skb_network_header_len(skb));
107 if (mh->ip6mh_proto != IPPROTO_NONE) {
108 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
110 mip6_param_prob(skb, 0, offsetof(struct ip6_mh, ip6mh_proto) +
111 skb_network_header_len(skb));
118 struct mip6_report_rate_limiter {
120 struct timeval stamp;
126 static struct mip6_report_rate_limiter mip6_report_rl = {
127 .lock = __SPIN_LOCK_UNLOCKED(mip6_report_rl.lock)
130 static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
132 const struct ipv6hdr *iph = ipv6_hdr(skb);
133 struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
134 int err = destopt->nexthdr;
137 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
138 !ipv6_addr_any((struct in6_addr *)x->coaddr))
140 spin_unlock(&x->lock);
145 /* Destination Option Header is inserted.
146 * IP Header's src address is replaced with Home Address Option in
147 * Destination Option Header.
149 static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
152 struct ipv6_destopt_hdr *dstopt;
153 struct ipv6_destopt_hao *hao;
157 skb_push(skb, -skb_network_offset(skb));
160 nexthdr = *skb_mac_header(skb);
161 *skb_mac_header(skb) = IPPROTO_DSTOPTS;
163 dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
164 dstopt->nexthdr = nexthdr;
166 hao = mip6_padn((char *)(dstopt + 1),
167 calc_padlen(sizeof(*dstopt), 6));
169 hao->type = IPV6_TLV_HAO;
170 BUILD_BUG_ON(sizeof(*hao) != 18);
171 hao->length = sizeof(*hao) - 2;
173 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
175 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
176 spin_lock_bh(&x->lock);
177 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
178 spin_unlock_bh(&x->lock);
180 WARN_ON(len != x->props.header_len);
181 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
186 static inline int mip6_report_rl_allow(struct timeval *stamp,
187 const struct in6_addr *dst,
188 const struct in6_addr *src, int iif)
192 spin_lock_bh(&mip6_report_rl.lock);
193 if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
194 mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
195 mip6_report_rl.iif != iif ||
196 !ipv6_addr_equal(&mip6_report_rl.src, src) ||
197 !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
198 mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
199 mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
200 mip6_report_rl.iif = iif;
201 mip6_report_rl.src = *src;
202 mip6_report_rl.dst = *dst;
205 spin_unlock_bh(&mip6_report_rl.lock);
209 static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb,
210 const struct flowi *fl)
212 struct net *net = xs_net(x);
213 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
214 const struct flowi6 *fl6 = &fl->u.ip6;
215 struct ipv6_destopt_hao *hao = NULL;
216 struct xfrm_selector sel;
218 struct timeval stamp;
221 if (unlikely(fl6->flowi6_proto == IPPROTO_MH &&
222 fl6->fl6_mh_type <= IP6_MH_TYPE_MAX))
225 if (likely(opt->dsthao)) {
226 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
227 if (likely(offset >= 0))
228 hao = (struct ipv6_destopt_hao *)
229 (skb_network_header(skb) + offset);
232 skb_get_timestamp(skb, &stamp);
234 if (!mip6_report_rl_allow(&stamp, &ipv6_hdr(skb)->daddr,
235 hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
239 memset(&sel, 0, sizeof(sel));
240 memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
242 sel.prefixlen_d = 128;
243 memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
245 sel.prefixlen_s = 128;
246 sel.family = AF_INET6;
247 sel.proto = fl6->flowi6_proto;
248 sel.dport = xfrm_flowi_dport(fl, &fl6->uli);
250 sel.dport_mask = htons(~0);
251 sel.sport = xfrm_flowi_sport(fl, &fl6->uli);
253 sel.sport_mask = htons(~0);
254 sel.ifindex = fl6->flowi6_oif;
256 err = km_report(net, IPPROTO_DSTOPTS, &sel,
257 (hao ? (xfrm_address_t *)&hao->addr : NULL));
263 static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
266 u16 offset = sizeof(struct ipv6hdr);
267 struct ipv6_opt_hdr *exthdr =
268 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
269 const unsigned char *nh = skb_network_header(skb);
270 unsigned int packet_len = skb_tail_pointer(skb) -
271 skb_network_header(skb);
274 *nexthdr = &ipv6_hdr(skb)->nexthdr;
276 while (offset + 1 <= packet_len) {
281 case NEXTHDR_ROUTING:
286 * HAO MUST NOT appear more than once.
287 * XXX: It is better to try to find by the end of
288 * XXX: packet if HAO exists.
290 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
291 LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
303 offset += ipv6_optlen(exthdr);
304 *nexthdr = &exthdr->nexthdr;
305 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
311 static int mip6_destopt_init_state(struct xfrm_state *x)
314 pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
317 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
318 pr_info("%s: state's mode is not %u: %u\n",
319 __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
323 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
324 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
325 sizeof(struct ipv6_destopt_hao);
326 WARN_ON(x->props.header_len != 24);
332 * Do nothing about destroying since it has no specific operation for
333 * destination options header unlike IPsec protocols.
335 static void mip6_destopt_destroy(struct xfrm_state *x)
339 static const struct xfrm_type mip6_destopt_type = {
340 .description = "MIP6DESTOPT",
341 .owner = THIS_MODULE,
342 .proto = IPPROTO_DSTOPTS,
343 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_LOCAL_COADDR,
344 .init_state = mip6_destopt_init_state,
345 .destructor = mip6_destopt_destroy,
346 .input = mip6_destopt_input,
347 .output = mip6_destopt_output,
348 .reject = mip6_destopt_reject,
349 .hdr_offset = mip6_destopt_offset,
352 static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
354 const struct ipv6hdr *iph = ipv6_hdr(skb);
355 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
356 int err = rt2->rt_hdr.nexthdr;
359 if (!ipv6_addr_equal(&iph->daddr, (struct in6_addr *)x->coaddr) &&
360 !ipv6_addr_any((struct in6_addr *)x->coaddr))
362 spin_unlock(&x->lock);
367 /* Routing Header type 2 is inserted.
368 * IP Header's dst address is replaced with Routing Header's Home Address.
370 static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
376 skb_push(skb, -skb_network_offset(skb));
379 nexthdr = *skb_mac_header(skb);
380 *skb_mac_header(skb) = IPPROTO_ROUTING;
382 rt2 = (struct rt2_hdr *)skb_transport_header(skb);
383 rt2->rt_hdr.nexthdr = nexthdr;
384 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
385 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
386 rt2->rt_hdr.segments_left = 1;
387 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
389 WARN_ON(rt2->rt_hdr.hdrlen != 2);
391 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
392 spin_lock_bh(&x->lock);
393 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
394 spin_unlock_bh(&x->lock);
399 static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
402 u16 offset = sizeof(struct ipv6hdr);
403 struct ipv6_opt_hdr *exthdr =
404 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
405 const unsigned char *nh = skb_network_header(skb);
406 unsigned int packet_len = skb_tail_pointer(skb) -
407 skb_network_header(skb);
410 *nexthdr = &ipv6_hdr(skb)->nexthdr;
412 while (offset + 1 <= packet_len) {
417 case NEXTHDR_ROUTING:
418 if (offset + 3 <= packet_len) {
419 struct ipv6_rt_hdr *rt;
420 rt = (struct ipv6_rt_hdr *)(nh + offset);
427 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
438 offset += ipv6_optlen(exthdr);
439 *nexthdr = &exthdr->nexthdr;
440 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
446 static int mip6_rthdr_init_state(struct xfrm_state *x)
449 pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
452 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
453 pr_info("%s: state's mode is not %u: %u\n",
454 __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
458 x->props.header_len = sizeof(struct rt2_hdr);
464 * Do nothing about destroying since it has no specific operation for routing
465 * header type 2 unlike IPsec protocols.
467 static void mip6_rthdr_destroy(struct xfrm_state *x)
471 static const struct xfrm_type mip6_rthdr_type = {
472 .description = "MIP6RT",
473 .owner = THIS_MODULE,
474 .proto = IPPROTO_ROUTING,
475 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_REMOTE_COADDR,
476 .init_state = mip6_rthdr_init_state,
477 .destructor = mip6_rthdr_destroy,
478 .input = mip6_rthdr_input,
479 .output = mip6_rthdr_output,
480 .hdr_offset = mip6_rthdr_offset,
483 static int __init mip6_init(void)
485 pr_info("Mobile IPv6\n");
487 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
488 pr_info("%s: can't add xfrm type(destopt)\n", __func__);
489 goto mip6_destopt_xfrm_fail;
491 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
492 pr_info("%s: can't add xfrm type(rthdr)\n", __func__);
493 goto mip6_rthdr_xfrm_fail;
495 if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
496 pr_info("%s: can't add rawv6 mh filter\n", __func__);
497 goto mip6_rawv6_mh_fail;
504 xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
505 mip6_rthdr_xfrm_fail:
506 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
507 mip6_destopt_xfrm_fail:
511 static void __exit mip6_fini(void)
513 if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
514 pr_info("%s: can't remove rawv6 mh filter\n", __func__);
515 if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
516 pr_info("%s: can't remove xfrm type(rthdr)\n", __func__);
517 if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
518 pr_info("%s: can't remove xfrm type(destopt)\n", __func__);
521 module_init(mip6_init);
522 module_exit(mip6_fini);
524 MODULE_LICENSE("GPL");
525 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
526 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);