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/config.h>
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>
37 static xfrm_address_t *mip6_xfrm_addr(struct xfrm_state *x, xfrm_address_t *addr)
42 static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
44 return (n - len + 16) & 0x7;
47 static inline void *mip6_padn(__u8 *data, __u8 padlen)
52 data[0] = MIP6_OPT_PAD_1;
53 } else if (padlen > 1) {
54 data[0] = MIP6_OPT_PAD_N;
57 memset(data+2, 0, data[1]);
62 static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos)
64 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
67 static int mip6_mh_len(int type)
75 case IP6_MH_TYPE_HOTI:
76 case IP6_MH_TYPE_COTI:
78 case IP6_MH_TYPE_BACK:
83 case IP6_MH_TYPE_BERROR:
90 int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
95 if (!pskb_may_pull(skb, (skb->h.raw - skb->data) + 8) ||
96 !pskb_may_pull(skb, (skb->h.raw - skb->data) + ((skb->h.raw[1] + 1) << 3)))
99 mh = (struct ip6_mh *)skb->h.raw;
101 if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
102 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
103 mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
104 mip6_param_prob(skb, 0, (&mh->ip6mh_hdrlen) - skb->nh.raw);
107 mhlen = (mh->ip6mh_hdrlen + 1) << 3;
109 if (skb->ip_summed == CHECKSUM_COMPLETE) {
110 skb->ip_summed = CHECKSUM_UNNECESSARY;
111 if (csum_ipv6_magic(&skb->nh.ipv6h->saddr,
112 &skb->nh.ipv6h->daddr,
115 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH hw checksum failed\n");
116 skb->ip_summed = CHECKSUM_NONE;
119 if (skb->ip_summed == CHECKSUM_NONE) {
120 if (csum_ipv6_magic(&skb->nh.ipv6h->saddr,
121 &skb->nh.ipv6h->daddr,
123 skb_checksum(skb, 0, mhlen, 0))) {
124 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH checksum failed [%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x > %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x]\n",
125 NIP6(skb->nh.ipv6h->saddr),
126 NIP6(skb->nh.ipv6h->daddr));
129 skb->ip_summed = CHECKSUM_UNNECESSARY;
132 if (mh->ip6mh_proto != IPPROTO_NONE) {
133 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
135 mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw);
142 struct mip6_report_rate_limiter {
144 struct timeval stamp;
150 static struct mip6_report_rate_limiter mip6_report_rl = {
151 .lock = SPIN_LOCK_UNLOCKED
154 static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
156 struct ipv6hdr *iph = skb->nh.ipv6h;
157 struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
159 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
160 !ipv6_addr_any((struct in6_addr *)x->coaddr))
163 return destopt->nexthdr;
166 /* Destination Option Header is inserted.
167 * IP Header's src address is replaced with Home Address Option in
168 * Destination Option Header.
170 static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
173 struct ipv6_destopt_hdr *dstopt;
174 struct ipv6_destopt_hao *hao;
178 iph = (struct ipv6hdr *)skb->data;
179 iph->payload_len = htons(skb->len - sizeof(*iph));
181 nexthdr = *skb->nh.raw;
182 *skb->nh.raw = IPPROTO_DSTOPTS;
184 dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
185 dstopt->nexthdr = nexthdr;
187 hao = mip6_padn((char *)(dstopt + 1),
188 calc_padlen(sizeof(*dstopt), 6));
190 hao->type = IPV6_TLV_HAO;
191 hao->length = sizeof(*hao) - 2;
192 BUG_TRAP(hao->length == 16);
194 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
196 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
197 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
199 BUG_TRAP(len == x->props.header_len);
200 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
205 static inline int mip6_report_rl_allow(struct timeval *stamp,
206 struct in6_addr *dst,
207 struct in6_addr *src, int iif)
211 spin_lock_bh(&mip6_report_rl.lock);
212 if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
213 mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
214 mip6_report_rl.iif != iif ||
215 !ipv6_addr_equal(&mip6_report_rl.src, src) ||
216 !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
217 mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
218 mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
219 mip6_report_rl.iif = iif;
220 ipv6_addr_copy(&mip6_report_rl.src, src);
221 ipv6_addr_copy(&mip6_report_rl.dst, dst);
224 spin_unlock_bh(&mip6_report_rl.lock);
228 static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb, struct flowi *fl)
230 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
231 struct ipv6_destopt_hao *hao = NULL;
232 struct xfrm_selector sel;
234 struct timeval stamp;
237 if (unlikely(fl->proto == IPPROTO_MH && fl->fl_mh_type <= IP6_MH_TYPE_MAX))
240 if (likely(opt->dsthao)) {
241 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
242 if (likely(offset >= 0))
243 hao = (struct ipv6_destopt_hao *)(skb->nh.raw + offset);
246 skb_get_timestamp(skb, &stamp);
248 if (!mip6_report_rl_allow(&stamp, &skb->nh.ipv6h->daddr,
249 hao ? &hao->addr : &skb->nh.ipv6h->saddr,
253 memset(&sel, 0, sizeof(sel));
254 memcpy(&sel.daddr, (xfrm_address_t *)&skb->nh.ipv6h->daddr,
256 sel.prefixlen_d = 128;
257 memcpy(&sel.saddr, (xfrm_address_t *)&skb->nh.ipv6h->saddr,
259 sel.prefixlen_s = 128;
260 sel.family = AF_INET6;
261 sel.proto = fl->proto;
262 sel.dport = xfrm_flowi_dport(fl);
264 sel.dport_mask = ~((__u16)0);
265 sel.sport = xfrm_flowi_sport(fl);
267 sel.sport_mask = ~((__u16)0);
268 sel.ifindex = fl->oif;
270 err = km_report(IPPROTO_DSTOPTS, &sel,
271 (hao ? (xfrm_address_t *)&hao->addr : NULL));
277 static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
280 u16 offset = sizeof(struct ipv6hdr);
281 struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
282 unsigned int packet_len = skb->tail - skb->nh.raw;
285 *nexthdr = &skb->nh.ipv6h->nexthdr;
287 while (offset + 1 <= packet_len) {
292 case NEXTHDR_ROUTING:
297 * HAO MUST NOT appear more than once.
298 * XXX: It is better to try to find by the end of
299 * XXX: packet if HAO exists.
301 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
302 LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
314 offset += ipv6_optlen(exthdr);
315 *nexthdr = &exthdr->nexthdr;
316 exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
322 static int mip6_destopt_init_state(struct xfrm_state *x)
325 printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
329 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
330 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
331 __FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
335 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
336 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
337 sizeof(struct ipv6_destopt_hao);
338 BUG_TRAP(x->props.header_len == 24);
344 * Do nothing about destroying since it has no specific operation for
345 * destination options header unlike IPsec protocols.
347 static void mip6_destopt_destroy(struct xfrm_state *x)
351 static struct xfrm_type mip6_destopt_type =
353 .description = "MIP6DESTOPT",
354 .owner = THIS_MODULE,
355 .proto = IPPROTO_DSTOPTS,
356 .flags = XFRM_TYPE_NON_FRAGMENT,
357 .init_state = mip6_destopt_init_state,
358 .destructor = mip6_destopt_destroy,
359 .input = mip6_destopt_input,
360 .output = mip6_destopt_output,
361 .reject = mip6_destopt_reject,
362 .hdr_offset = mip6_destopt_offset,
363 .local_addr = mip6_xfrm_addr,
366 static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
368 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
370 if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
371 !ipv6_addr_any((struct in6_addr *)x->coaddr))
374 return rt2->rt_hdr.nexthdr;
377 /* Routing Header type 2 is inserted.
378 * IP Header's dst address is replaced with Routing Header's Home Address.
380 static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
386 iph = (struct ipv6hdr *)skb->data;
387 iph->payload_len = htons(skb->len - sizeof(*iph));
389 nexthdr = *skb->nh.raw;
390 *skb->nh.raw = IPPROTO_ROUTING;
392 rt2 = (struct rt2_hdr *)skb->h.raw;
393 rt2->rt_hdr.nexthdr = nexthdr;
394 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
395 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
396 rt2->rt_hdr.segments_left = 1;
397 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
399 BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
401 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
402 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
407 static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
410 u16 offset = sizeof(struct ipv6hdr);
411 struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
412 unsigned int packet_len = skb->tail - skb->nh.raw;
415 *nexthdr = &skb->nh.ipv6h->nexthdr;
417 while (offset + 1 <= packet_len) {
422 case NEXTHDR_ROUTING:
423 if (offset + 3 <= packet_len) {
424 struct ipv6_rt_hdr *rt;
425 rt = (struct ipv6_rt_hdr *)(skb->nh.raw + offset);
432 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
443 offset += ipv6_optlen(exthdr);
444 *nexthdr = &exthdr->nexthdr;
445 exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
451 static int mip6_rthdr_init_state(struct xfrm_state *x)
454 printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
458 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
459 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
460 __FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
464 x->props.header_len = sizeof(struct rt2_hdr);
470 * Do nothing about destroying since it has no specific operation for routing
471 * header type 2 unlike IPsec protocols.
473 static void mip6_rthdr_destroy(struct xfrm_state *x)
477 static struct xfrm_type mip6_rthdr_type =
479 .description = "MIP6RT",
480 .owner = THIS_MODULE,
481 .proto = IPPROTO_ROUTING,
482 .flags = XFRM_TYPE_NON_FRAGMENT,
483 .init_state = mip6_rthdr_init_state,
484 .destructor = mip6_rthdr_destroy,
485 .input = mip6_rthdr_input,
486 .output = mip6_rthdr_output,
487 .hdr_offset = mip6_rthdr_offset,
488 .remote_addr = mip6_xfrm_addr,
491 int __init mip6_init(void)
493 printk(KERN_INFO "Mobile IPv6\n");
495 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
496 printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __FUNCTION__);
497 goto mip6_destopt_xfrm_fail;
499 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
500 printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __FUNCTION__);
501 goto mip6_rthdr_xfrm_fail;
505 mip6_rthdr_xfrm_fail:
506 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
507 mip6_destopt_xfrm_fail:
511 void __exit mip6_fini(void)
513 if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
514 printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
515 if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
516 printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);