btrfs: clear __GFP_FS flag in the space cache inode
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv6 / mip6.c
blobd6e9599d0705a5b79749a0566cbd97dfaa9993c0
1 /*
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
20 * Authors:
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>
30 #include <net/sock.h>
31 #include <net/ipv6.h>
32 #include <net/ip6_checksum.h>
33 #include <net/rawv6.h>
34 #include <net/xfrm.h>
35 #include <net/mip6.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)
44 if (!data)
45 return NULL;
46 if (padlen == 1) {
47 data[0] = IPV6_TLV_PAD0;
48 } else if (padlen > 1) {
49 data[0] = IPV6_TLV_PADN;
50 data[1] = padlen - 2;
51 if (padlen > 2)
52 memset(data+2, 0, data[1]);
54 return data + padlen;
57 static inline void mip6_param_prob(struct sk_buff *skb, u8 code, int pos)
59 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
62 static int mip6_mh_len(int type)
64 int len = 0;
66 switch (type) {
67 case IP6_MH_TYPE_BRR:
68 len = 0;
69 break;
70 case IP6_MH_TYPE_HOTI:
71 case IP6_MH_TYPE_COTI:
72 case IP6_MH_TYPE_BU:
73 case IP6_MH_TYPE_BACK:
74 len = 1;
75 break;
76 case IP6_MH_TYPE_HOT:
77 case IP6_MH_TYPE_COT:
78 case IP6_MH_TYPE_BERROR:
79 len = 2;
80 break;
82 return len;
85 static int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
87 struct ip6_mh *mh;
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))))
92 return -1;
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)));
101 return -1;
104 if (mh->ip6mh_proto != IPPROTO_NONE) {
105 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
106 mh->ip6mh_proto);
107 mip6_param_prob(skb, 0, ((&mh->ip6mh_proto) -
108 skb_network_header(skb)));
109 return -1;
112 return 0;
115 struct mip6_report_rate_limiter {
116 spinlock_t lock;
117 struct timeval stamp;
118 int iif;
119 struct in6_addr src;
120 struct in6_addr dst;
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;
131 int err = destopt->nexthdr;
133 spin_lock(&x->lock);
134 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
135 !ipv6_addr_any((struct in6_addr *)x->coaddr))
136 err = -ENOENT;
137 spin_unlock(&x->lock);
139 return err;
142 /* Destination Option Header is inserted.
143 * IP Header's src address is replaced with Home Address Option in
144 * Destination Option Header.
146 static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
148 struct ipv6hdr *iph;
149 struct ipv6_destopt_hdr *dstopt;
150 struct ipv6_destopt_hao *hao;
151 u8 nexthdr;
152 int len;
154 skb_push(skb, -skb_network_offset(skb));
155 iph = ipv6_hdr(skb);
157 nexthdr = *skb_mac_header(skb);
158 *skb_mac_header(skb) = IPPROTO_DSTOPTS;
160 dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
161 dstopt->nexthdr = nexthdr;
163 hao = mip6_padn((char *)(dstopt + 1),
164 calc_padlen(sizeof(*dstopt), 6));
166 hao->type = IPV6_TLV_HAO;
167 BUILD_BUG_ON(sizeof(*hao) != 18);
168 hao->length = sizeof(*hao) - 2;
170 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
172 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
173 spin_lock_bh(&x->lock);
174 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
175 spin_unlock_bh(&x->lock);
177 WARN_ON(len != x->props.header_len);
178 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
180 return 0;
183 static inline int mip6_report_rl_allow(struct timeval *stamp,
184 struct in6_addr *dst,
185 struct in6_addr *src, int iif)
187 int allow = 0;
189 spin_lock_bh(&mip6_report_rl.lock);
190 if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
191 mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
192 mip6_report_rl.iif != iif ||
193 !ipv6_addr_equal(&mip6_report_rl.src, src) ||
194 !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
195 mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
196 mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
197 mip6_report_rl.iif = iif;
198 ipv6_addr_copy(&mip6_report_rl.src, src);
199 ipv6_addr_copy(&mip6_report_rl.dst, dst);
200 allow = 1;
202 spin_unlock_bh(&mip6_report_rl.lock);
203 return allow;
206 static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb, struct flowi *fl)
208 struct net *net = xs_net(x);
209 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
210 struct ipv6_destopt_hao *hao = NULL;
211 struct xfrm_selector sel;
212 int offset;
213 struct timeval stamp;
214 int err = 0;
216 if (unlikely(fl->proto == IPPROTO_MH &&
217 fl->fl_mh_type <= IP6_MH_TYPE_MAX))
218 goto out;
220 if (likely(opt->dsthao)) {
221 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
222 if (likely(offset >= 0))
223 hao = (struct ipv6_destopt_hao *)
224 (skb_network_header(skb) + offset);
227 skb_get_timestamp(skb, &stamp);
229 if (!mip6_report_rl_allow(&stamp, &ipv6_hdr(skb)->daddr,
230 hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
231 opt->iif))
232 goto out;
234 memset(&sel, 0, sizeof(sel));
235 memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
236 sizeof(sel.daddr));
237 sel.prefixlen_d = 128;
238 memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
239 sizeof(sel.saddr));
240 sel.prefixlen_s = 128;
241 sel.family = AF_INET6;
242 sel.proto = fl->proto;
243 sel.dport = xfrm_flowi_dport(fl);
244 if (sel.dport)
245 sel.dport_mask = htons(~0);
246 sel.sport = xfrm_flowi_sport(fl);
247 if (sel.sport)
248 sel.sport_mask = htons(~0);
249 sel.ifindex = fl->oif;
251 err = km_report(net, IPPROTO_DSTOPTS, &sel,
252 (hao ? (xfrm_address_t *)&hao->addr : NULL));
254 out:
255 return err;
258 static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
259 u8 **nexthdr)
261 u16 offset = sizeof(struct ipv6hdr);
262 struct ipv6_opt_hdr *exthdr =
263 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
264 const unsigned char *nh = skb_network_header(skb);
265 unsigned int packet_len = skb->tail - skb->network_header;
266 int found_rhdr = 0;
268 *nexthdr = &ipv6_hdr(skb)->nexthdr;
270 while (offset + 1 <= packet_len) {
272 switch (**nexthdr) {
273 case NEXTHDR_HOP:
274 break;
275 case NEXTHDR_ROUTING:
276 found_rhdr = 1;
277 break;
278 case NEXTHDR_DEST:
280 * HAO MUST NOT appear more than once.
281 * XXX: It is better to try to find by the end of
282 * XXX: packet if HAO exists.
284 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
285 LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
286 return offset;
289 if (found_rhdr)
290 return offset;
292 break;
293 default:
294 return offset;
297 offset += ipv6_optlen(exthdr);
298 *nexthdr = &exthdr->nexthdr;
299 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
302 return offset;
305 static int mip6_destopt_init_state(struct xfrm_state *x)
307 if (x->id.spi) {
308 printk(KERN_INFO "%s: spi is not 0: %u\n", __func__,
309 x->id.spi);
310 return -EINVAL;
312 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
313 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
314 __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
315 return -EINVAL;
318 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
319 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
320 sizeof(struct ipv6_destopt_hao);
321 WARN_ON(x->props.header_len != 24);
323 return 0;
327 * Do nothing about destroying since it has no specific operation for
328 * destination options header unlike IPsec protocols.
330 static void mip6_destopt_destroy(struct xfrm_state *x)
334 static const struct xfrm_type mip6_destopt_type =
336 .description = "MIP6DESTOPT",
337 .owner = THIS_MODULE,
338 .proto = IPPROTO_DSTOPTS,
339 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_LOCAL_COADDR,
340 .init_state = mip6_destopt_init_state,
341 .destructor = mip6_destopt_destroy,
342 .input = mip6_destopt_input,
343 .output = mip6_destopt_output,
344 .reject = mip6_destopt_reject,
345 .hdr_offset = mip6_destopt_offset,
348 static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
350 struct ipv6hdr *iph = ipv6_hdr(skb);
351 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
352 int err = rt2->rt_hdr.nexthdr;
354 spin_lock(&x->lock);
355 if (!ipv6_addr_equal(&iph->daddr, (struct in6_addr *)x->coaddr) &&
356 !ipv6_addr_any((struct in6_addr *)x->coaddr))
357 err = -ENOENT;
358 spin_unlock(&x->lock);
360 return err;
363 /* Routing Header type 2 is inserted.
364 * IP Header's dst address is replaced with Routing Header's Home Address.
366 static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
368 struct ipv6hdr *iph;
369 struct rt2_hdr *rt2;
370 u8 nexthdr;
372 skb_push(skb, -skb_network_offset(skb));
373 iph = ipv6_hdr(skb);
375 nexthdr = *skb_mac_header(skb);
376 *skb_mac_header(skb) = IPPROTO_ROUTING;
378 rt2 = (struct rt2_hdr *)skb_transport_header(skb);
379 rt2->rt_hdr.nexthdr = nexthdr;
380 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
381 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
382 rt2->rt_hdr.segments_left = 1;
383 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
385 WARN_ON(rt2->rt_hdr.hdrlen != 2);
387 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
388 spin_lock_bh(&x->lock);
389 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
390 spin_unlock_bh(&x->lock);
392 return 0;
395 static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
396 u8 **nexthdr)
398 u16 offset = sizeof(struct ipv6hdr);
399 struct ipv6_opt_hdr *exthdr =
400 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
401 const unsigned char *nh = skb_network_header(skb);
402 unsigned int packet_len = skb->tail - skb->network_header;
403 int found_rhdr = 0;
405 *nexthdr = &ipv6_hdr(skb)->nexthdr;
407 while (offset + 1 <= packet_len) {
409 switch (**nexthdr) {
410 case NEXTHDR_HOP:
411 break;
412 case NEXTHDR_ROUTING:
413 if (offset + 3 <= packet_len) {
414 struct ipv6_rt_hdr *rt;
415 rt = (struct ipv6_rt_hdr *)(nh + offset);
416 if (rt->type != 0)
417 return offset;
419 found_rhdr = 1;
420 break;
421 case NEXTHDR_DEST:
422 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
423 return offset;
425 if (found_rhdr)
426 return offset;
428 break;
429 default:
430 return offset;
433 offset += ipv6_optlen(exthdr);
434 *nexthdr = &exthdr->nexthdr;
435 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
438 return offset;
441 static int mip6_rthdr_init_state(struct xfrm_state *x)
443 if (x->id.spi) {
444 printk(KERN_INFO "%s: spi is not 0: %u\n", __func__,
445 x->id.spi);
446 return -EINVAL;
448 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
449 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
450 __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
451 return -EINVAL;
454 x->props.header_len = sizeof(struct rt2_hdr);
456 return 0;
460 * Do nothing about destroying since it has no specific operation for routing
461 * header type 2 unlike IPsec protocols.
463 static void mip6_rthdr_destroy(struct xfrm_state *x)
467 static const struct xfrm_type mip6_rthdr_type =
469 .description = "MIP6RT",
470 .owner = THIS_MODULE,
471 .proto = IPPROTO_ROUTING,
472 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_REMOTE_COADDR,
473 .init_state = mip6_rthdr_init_state,
474 .destructor = mip6_rthdr_destroy,
475 .input = mip6_rthdr_input,
476 .output = mip6_rthdr_output,
477 .hdr_offset = mip6_rthdr_offset,
480 static int __init mip6_init(void)
482 printk(KERN_INFO "Mobile IPv6\n");
484 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
485 printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __func__);
486 goto mip6_destopt_xfrm_fail;
488 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
489 printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __func__);
490 goto mip6_rthdr_xfrm_fail;
492 if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
493 printk(KERN_INFO "%s: can't add rawv6 mh filter\n", __func__);
494 goto mip6_rawv6_mh_fail;
498 return 0;
500 mip6_rawv6_mh_fail:
501 xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
502 mip6_rthdr_xfrm_fail:
503 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
504 mip6_destopt_xfrm_fail:
505 return -EAGAIN;
508 static void __exit mip6_fini(void)
510 if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
511 printk(KERN_INFO "%s: can't remove rawv6 mh filter\n", __func__);
512 if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
513 printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __func__);
514 if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
515 printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __func__);
518 module_init(mip6_init);
519 module_exit(mip6_fini);
521 MODULE_LICENSE("GPL");
522 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
523 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);