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, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 * Noriaki TAKAMIYA @USAGI
22 * Masahide NAKAMURA @USAGI
25 #include <linux/module.h>
26 #include <linux/skbuff.h>
27 #include <linux/time.h>
28 #include <linux/ipv6.h>
29 #include <linux/icmpv6.h>
32 #include <net/ip6_checksum.h>
33 #include <net/rawv6.h>
37 static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
39 return (n - len + 16) & 0x7;
42 static inline void *mip6_padn(__u8 *data, __u8 padlen)
47 data[0] = MIP6_OPT_PAD_1;
48 } else if (padlen > 1) {
49 data[0] = MIP6_OPT_PAD_N;
52 memset(data+2, 0, data[1]);
57 static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos)
59 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
62 static int mip6_mh_len(int type)
70 case IP6_MH_TYPE_HOTI:
71 case IP6_MH_TYPE_COTI:
73 case IP6_MH_TYPE_BACK:
78 case IP6_MH_TYPE_BERROR:
85 static int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
89 if (!pskb_may_pull(skb, (skb_transport_offset(skb)) + 8) ||
90 !pskb_may_pull(skb, (skb_transport_offset(skb) +
91 ((skb_transport_header(skb)[1] + 1) << 3))))
94 mh = (struct ip6_mh *)skb_transport_header(skb);
96 if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
97 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
98 mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
99 mip6_param_prob(skb, 0, ((&mh->ip6mh_hdrlen) -
100 skb_network_header(skb)));
104 if (mh->ip6mh_proto != IPPROTO_NONE) {
105 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
107 mip6_param_prob(skb, 0, ((&mh->ip6mh_proto) -
108 skb_network_header(skb)));
115 struct mip6_report_rate_limiter {
117 struct timeval stamp;
123 static struct mip6_report_rate_limiter mip6_report_rl = {
124 .lock = __SPIN_LOCK_UNLOCKED(mip6_report_rl.lock)
127 static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
129 struct ipv6hdr *iph = ipv6_hdr(skb);
130 struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
132 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
133 !ipv6_addr_any((struct in6_addr *)x->coaddr))
136 return destopt->nexthdr;
139 /* Destination Option Header is inserted.
140 * IP Header's src address is replaced with Home Address Option in
141 * Destination Option Header.
143 static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
146 struct ipv6_destopt_hdr *dstopt;
147 struct ipv6_destopt_hao *hao;
151 skb_push(skb, -skb_network_offset(skb));
154 nexthdr = *skb_mac_header(skb);
155 *skb_mac_header(skb) = IPPROTO_DSTOPTS;
157 dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
158 dstopt->nexthdr = nexthdr;
160 hao = mip6_padn((char *)(dstopt + 1),
161 calc_padlen(sizeof(*dstopt), 6));
163 hao->type = IPV6_TLV_HAO;
164 hao->length = sizeof(*hao) - 2;
165 BUG_TRAP(hao->length == 16);
167 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
169 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
170 spin_lock_bh(&x->lock);
171 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
172 spin_unlock_bh(&x->lock);
174 BUG_TRAP(len == x->props.header_len);
175 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
180 static inline int mip6_report_rl_allow(struct timeval *stamp,
181 struct in6_addr *dst,
182 struct in6_addr *src, int iif)
186 spin_lock_bh(&mip6_report_rl.lock);
187 if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
188 mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
189 mip6_report_rl.iif != iif ||
190 !ipv6_addr_equal(&mip6_report_rl.src, src) ||
191 !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
192 mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
193 mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
194 mip6_report_rl.iif = iif;
195 ipv6_addr_copy(&mip6_report_rl.src, src);
196 ipv6_addr_copy(&mip6_report_rl.dst, dst);
199 spin_unlock_bh(&mip6_report_rl.lock);
203 static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb, struct flowi *fl)
205 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
206 struct ipv6_destopt_hao *hao = NULL;
207 struct xfrm_selector sel;
209 struct timeval stamp;
212 if (unlikely(fl->proto == IPPROTO_MH &&
213 fl->fl_mh_type <= IP6_MH_TYPE_MAX))
216 if (likely(opt->dsthao)) {
217 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
218 if (likely(offset >= 0))
219 hao = (struct ipv6_destopt_hao *)
220 (skb_network_header(skb) + offset);
223 skb_get_timestamp(skb, &stamp);
225 if (!mip6_report_rl_allow(&stamp, &ipv6_hdr(skb)->daddr,
226 hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
230 memset(&sel, 0, sizeof(sel));
231 memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
233 sel.prefixlen_d = 128;
234 memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
236 sel.prefixlen_s = 128;
237 sel.family = AF_INET6;
238 sel.proto = fl->proto;
239 sel.dport = xfrm_flowi_dport(fl);
241 sel.dport_mask = htons(~0);
242 sel.sport = xfrm_flowi_sport(fl);
244 sel.sport_mask = htons(~0);
245 sel.ifindex = fl->oif;
247 err = km_report(IPPROTO_DSTOPTS, &sel,
248 (hao ? (xfrm_address_t *)&hao->addr : NULL));
254 static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
257 u16 offset = sizeof(struct ipv6hdr);
258 struct ipv6_opt_hdr *exthdr =
259 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
260 const unsigned char *nh = skb_network_header(skb);
261 unsigned int packet_len = skb->tail - skb->network_header;
264 *nexthdr = &ipv6_hdr(skb)->nexthdr;
266 while (offset + 1 <= packet_len) {
271 case NEXTHDR_ROUTING:
276 * HAO MUST NOT appear more than once.
277 * XXX: It is better to try to find by the end of
278 * XXX: packet if HAO exists.
280 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
281 LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
293 offset += ipv6_optlen(exthdr);
294 *nexthdr = &exthdr->nexthdr;
295 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
301 static int mip6_destopt_init_state(struct xfrm_state *x)
304 printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
308 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
309 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
310 __FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
314 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
315 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
316 sizeof(struct ipv6_destopt_hao);
317 BUG_TRAP(x->props.header_len == 24);
323 * Do nothing about destroying since it has no specific operation for
324 * destination options header unlike IPsec protocols.
326 static void mip6_destopt_destroy(struct xfrm_state *x)
330 static struct xfrm_type mip6_destopt_type =
332 .description = "MIP6DESTOPT",
333 .owner = THIS_MODULE,
334 .proto = IPPROTO_DSTOPTS,
335 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_LOCAL_COADDR,
336 .init_state = mip6_destopt_init_state,
337 .destructor = mip6_destopt_destroy,
338 .input = mip6_destopt_input,
339 .output = mip6_destopt_output,
340 .reject = mip6_destopt_reject,
341 .hdr_offset = mip6_destopt_offset,
344 static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
346 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
348 if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
349 !ipv6_addr_any((struct in6_addr *)x->coaddr))
352 return rt2->rt_hdr.nexthdr;
355 /* Routing Header type 2 is inserted.
356 * IP Header's dst address is replaced with Routing Header's Home Address.
358 static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
364 skb_push(skb, -skb_network_offset(skb));
367 nexthdr = *skb_mac_header(skb);
368 *skb_mac_header(skb) = IPPROTO_ROUTING;
370 rt2 = (struct rt2_hdr *)skb_transport_header(skb);
371 rt2->rt_hdr.nexthdr = nexthdr;
372 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
373 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
374 rt2->rt_hdr.segments_left = 1;
375 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
377 BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
379 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
380 spin_lock_bh(&x->lock);
381 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
382 spin_unlock_bh(&x->lock);
387 static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
390 u16 offset = sizeof(struct ipv6hdr);
391 struct ipv6_opt_hdr *exthdr =
392 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
393 const unsigned char *nh = skb_network_header(skb);
394 unsigned int packet_len = skb->tail - skb->network_header;
397 *nexthdr = &ipv6_hdr(skb)->nexthdr;
399 while (offset + 1 <= packet_len) {
404 case NEXTHDR_ROUTING:
405 if (offset + 3 <= packet_len) {
406 struct ipv6_rt_hdr *rt;
407 rt = (struct ipv6_rt_hdr *)(nh + offset);
414 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
425 offset += ipv6_optlen(exthdr);
426 *nexthdr = &exthdr->nexthdr;
427 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
433 static int mip6_rthdr_init_state(struct xfrm_state *x)
436 printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
440 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
441 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
442 __FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
446 x->props.header_len = sizeof(struct rt2_hdr);
452 * Do nothing about destroying since it has no specific operation for routing
453 * header type 2 unlike IPsec protocols.
455 static void mip6_rthdr_destroy(struct xfrm_state *x)
459 static struct xfrm_type mip6_rthdr_type =
461 .description = "MIP6RT",
462 .owner = THIS_MODULE,
463 .proto = IPPROTO_ROUTING,
464 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_REMOTE_COADDR,
465 .init_state = mip6_rthdr_init_state,
466 .destructor = mip6_rthdr_destroy,
467 .input = mip6_rthdr_input,
468 .output = mip6_rthdr_output,
469 .hdr_offset = mip6_rthdr_offset,
472 static int __init mip6_init(void)
474 printk(KERN_INFO "Mobile IPv6\n");
476 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
477 printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __FUNCTION__);
478 goto mip6_destopt_xfrm_fail;
480 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
481 printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __FUNCTION__);
482 goto mip6_rthdr_xfrm_fail;
484 if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
485 printk(KERN_INFO "%s: can't add rawv6 mh filter\n", __FUNCTION__);
486 goto mip6_rawv6_mh_fail;
493 xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
494 mip6_rthdr_xfrm_fail:
495 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
496 mip6_destopt_xfrm_fail:
500 static void __exit mip6_fini(void)
502 if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
503 printk(KERN_INFO "%s: can't remove rawv6 mh filter\n", __FUNCTION__);
504 if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
505 printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
506 if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
507 printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);
510 module_init(mip6_init);
511 module_exit(mip6_fini);
513 MODULE_LICENSE("GPL");
514 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
515 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);