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[PATCH] Fix VMI and COMPAT_VDSO for 2.6.21
[linux-2.6/mini2440.git] / net / ipv6 / mip6.c
blob0afcabdd8ed6c9a52d434cce18ca96495dcc591c
1 /*
2 * Copyright (C)2003-2006 Helsinki University of Technology
3 * Copyright (C)2003-2006 USAGI/WIDE Project
4 *
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.
9 *
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.
14 *
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
18 */
19 /*
20 * Authors:
21 * Noriaki TAKAMIYA @USAGI
22 * Masahide NAKAMURA @USAGI
23 */
24
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/xfrm.h>
34 #include <net/mip6.h>
35
36 static xfrm_address_t *mip6_xfrm_addr(struct xfrm_state *x, xfrm_address_t *addr)
37 {
38 return x->coaddr;
39 }
40
41 static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
42 {
43 return (n - len + 16) & 0x7;
44 }
45
46 static inline void *mip6_padn(__u8 *data, __u8 padlen)
47 {
48 if (!data)
49 return NULL;
50 if (padlen == 1) {
51 data[0] = MIP6_OPT_PAD_1;
52 } else if (padlen > 1) {
53 data[0] = MIP6_OPT_PAD_N;
54 data[1] = padlen - 2;
55 if (padlen > 2)
56 memset(data+2, 0, data[1]);
57 }
58 return data + padlen;
59 }
60
61 static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos)
62 {
63 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
64 }
65
66 static int mip6_mh_len(int type)
67 {
68 int len = 0;
69
70 switch (type) {
71 case IP6_MH_TYPE_BRR:
72 len = 0;
73 break;
74 case IP6_MH_TYPE_HOTI:
75 case IP6_MH_TYPE_COTI:
76 case IP6_MH_TYPE_BU:
77 case IP6_MH_TYPE_BACK:
78 len = 1;
79 break;
80 case IP6_MH_TYPE_HOT:
81 case IP6_MH_TYPE_COT:
82 case IP6_MH_TYPE_BERROR:
83 len = 2;
84 break;
85 }
86 return len;
87 }
88
89 int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
90 {
91 struct ip6_mh *mh;
92
93 if (!pskb_may_pull(skb, (skb->h.raw - skb->data) + 8) ||
94 !pskb_may_pull(skb, (skb->h.raw - skb->data) + ((skb->h.raw[1] + 1) << 3)))
95 return -1;
96
97 mh = (struct ip6_mh *)skb->h.raw;
98
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, (&mh->ip6mh_hdrlen) - skb->nh.raw);
103 return -1;
104 }
105
106 if (mh->ip6mh_proto != IPPROTO_NONE) {
107 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
108 mh->ip6mh_proto);
109 mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw);
110 return -1;
111 }
112
113 return 0;
114 }
115
116 struct mip6_report_rate_limiter {
117 spinlock_t lock;
118 struct timeval stamp;
119 int iif;
120 struct in6_addr src;
121 struct in6_addr dst;
122 };
123
124 static struct mip6_report_rate_limiter mip6_report_rl = {
125 .lock = SPIN_LOCK_UNLOCKED
126 };
127
128 static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
129 {
130 struct ipv6hdr *iph = skb->nh.ipv6h;
131 struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
132
133 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
134 !ipv6_addr_any((struct in6_addr *)x->coaddr))
135 return -ENOENT;
136
137 return destopt->nexthdr;
138 }
139
140 /* Destination Option Header is inserted.
141 * IP Header's src address is replaced with Home Address Option in
142 * Destination Option Header.
143 */
144 static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
145 {
146 struct ipv6hdr *iph;
147 struct ipv6_destopt_hdr *dstopt;
148 struct ipv6_destopt_hao *hao;
149 u8 nexthdr;
150 int len;
151
152 iph = (struct ipv6hdr *)skb->data;
153 iph->payload_len = htons(skb->len - sizeof(*iph));
154
155 nexthdr = *skb->nh.raw;
156 *skb->nh.raw = IPPROTO_DSTOPTS;
157
158 dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
159 dstopt->nexthdr = nexthdr;
160
161 hao = mip6_padn((char *)(dstopt + 1),
162 calc_padlen(sizeof(*dstopt), 6));
163
164 hao->type = IPV6_TLV_HAO;
165 hao->length = sizeof(*hao) - 2;
166 BUG_TRAP(hao->length == 16);
167
168 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
169
170 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
171 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
172
173 BUG_TRAP(len == x->props.header_len);
174 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
175
176 return 0;
177 }
178
179 static inline int mip6_report_rl_allow(struct timeval *stamp,
180 struct in6_addr *dst,
181 struct in6_addr *src, int iif)
182 {
183 int allow = 0;
184
185 spin_lock_bh(&mip6_report_rl.lock);
186 if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
187 mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
188 mip6_report_rl.iif != iif ||
189 !ipv6_addr_equal(&mip6_report_rl.src, src) ||
190 !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
191 mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
192 mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
193 mip6_report_rl.iif = iif;
194 ipv6_addr_copy(&mip6_report_rl.src, src);
195 ipv6_addr_copy(&mip6_report_rl.dst, dst);
196 allow = 1;
197 }
198 spin_unlock_bh(&mip6_report_rl.lock);
199 return allow;
200 }
201
202 static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb, struct flowi *fl)
203 {
204 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
205 struct ipv6_destopt_hao *hao = NULL;
206 struct xfrm_selector sel;
207 int offset;
208 struct timeval stamp;
209 int err = 0;
210
211 if (unlikely(fl->proto == IPPROTO_MH &&
212 fl->fl_mh_type <= IP6_MH_TYPE_MAX))
213 goto out;
214
215 if (likely(opt->dsthao)) {
216 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
217 if (likely(offset >= 0))
218 hao = (struct ipv6_destopt_hao *)(skb->nh.raw + offset);
219 }
220
221 skb_get_timestamp(skb, &stamp);
222
223 if (!mip6_report_rl_allow(&stamp, &skb->nh.ipv6h->daddr,
224 hao ? &hao->addr : &skb->nh.ipv6h->saddr,
225 opt->iif))
226 goto out;
227
228 memset(&sel, 0, sizeof(sel));
229 memcpy(&sel.daddr, (xfrm_address_t *)&skb->nh.ipv6h->daddr,
230 sizeof(sel.daddr));
231 sel.prefixlen_d = 128;
232 memcpy(&sel.saddr, (xfrm_address_t *)&skb->nh.ipv6h->saddr,
233 sizeof(sel.saddr));
234 sel.prefixlen_s = 128;
235 sel.family = AF_INET6;
236 sel.proto = fl->proto;
237 sel.dport = xfrm_flowi_dport(fl);
238 if (sel.dport)
239 sel.dport_mask = htons(~0);
240 sel.sport = xfrm_flowi_sport(fl);
241 if (sel.sport)
242 sel.sport_mask = htons(~0);
243 sel.ifindex = fl->oif;
244
245 err = km_report(IPPROTO_DSTOPTS, &sel,
246 (hao ? (xfrm_address_t *)&hao->addr : NULL));
247
248 out:
249 return err;
250 }
251
252 static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
253 u8 **nexthdr)
254 {
255 u16 offset = sizeof(struct ipv6hdr);
256 struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
257 unsigned int packet_len = skb->tail - skb->nh.raw;
258 int found_rhdr = 0;
259
260 *nexthdr = &skb->nh.ipv6h->nexthdr;
261
262 while (offset + 1 <= packet_len) {
263
264 switch (**nexthdr) {
265 case NEXTHDR_HOP:
266 break;
267 case NEXTHDR_ROUTING:
268 found_rhdr = 1;
269 break;
270 case NEXTHDR_DEST:
271 /*
272 * HAO MUST NOT appear more than once.
273 * XXX: It is better to try to find by the end of
274 * XXX: packet if HAO exists.
275 */
276 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
277 LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
278 return offset;
279 }
280
281 if (found_rhdr)
282 return offset;
283
284 break;
285 default:
286 return offset;
287 }
288
289 offset += ipv6_optlen(exthdr);
290 *nexthdr = &exthdr->nexthdr;
291 exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
292 }
293
294 return offset;
295 }
296
297 static int mip6_destopt_init_state(struct xfrm_state *x)
298 {
299 if (x->id.spi) {
300 printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
301 x->id.spi);
302 return -EINVAL;
303 }
304 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
305 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
306 __FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
307 return -EINVAL;
308 }
309
310 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
311 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
312 sizeof(struct ipv6_destopt_hao);
313 BUG_TRAP(x->props.header_len == 24);
314
315 return 0;
316 }
317
318 /*
319 * Do nothing about destroying since it has no specific operation for
320 * destination options header unlike IPsec protocols.
321 */
322 static void mip6_destopt_destroy(struct xfrm_state *x)
323 {
324 }
325
326 static struct xfrm_type mip6_destopt_type =
327 {
328 .description = "MIP6DESTOPT",
329 .owner = THIS_MODULE,
330 .proto = IPPROTO_DSTOPTS,
331 .flags = XFRM_TYPE_NON_FRAGMENT,
332 .init_state = mip6_destopt_init_state,
333 .destructor = mip6_destopt_destroy,
334 .input = mip6_destopt_input,
335 .output = mip6_destopt_output,
336 .reject = mip6_destopt_reject,
337 .hdr_offset = mip6_destopt_offset,
338 .local_addr = mip6_xfrm_addr,
339 };
340
341 static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
342 {
343 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
344
345 if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
346 !ipv6_addr_any((struct in6_addr *)x->coaddr))
347 return -ENOENT;
348
349 return rt2->rt_hdr.nexthdr;
350 }
351
352 /* Routing Header type 2 is inserted.
353 * IP Header's dst address is replaced with Routing Header's Home Address.
354 */
355 static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
356 {
357 struct ipv6hdr *iph;
358 struct rt2_hdr *rt2;
359 u8 nexthdr;
360
361 iph = (struct ipv6hdr *)skb->data;
362 iph->payload_len = htons(skb->len - sizeof(*iph));
363
364 nexthdr = *skb->nh.raw;
365 *skb->nh.raw = IPPROTO_ROUTING;
366
367 rt2 = (struct rt2_hdr *)skb->h.raw;
368 rt2->rt_hdr.nexthdr = nexthdr;
369 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
370 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
371 rt2->rt_hdr.segments_left = 1;
372 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
373
374 BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
375
376 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
377 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
378
379 return 0;
380 }
381
382 static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
383 u8 **nexthdr)
384 {
385 u16 offset = sizeof(struct ipv6hdr);
386 struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
387 unsigned int packet_len = skb->tail - skb->nh.raw;
388 int found_rhdr = 0;
389
390 *nexthdr = &skb->nh.ipv6h->nexthdr;
391
392 while (offset + 1 <= packet_len) {
393
394 switch (**nexthdr) {
395 case NEXTHDR_HOP:
396 break;
397 case NEXTHDR_ROUTING:
398 if (offset + 3 <= packet_len) {
399 struct ipv6_rt_hdr *rt;
400 rt = (struct ipv6_rt_hdr *)(skb->nh.raw + offset);
401 if (rt->type != 0)
402 return offset;
403 }
404 found_rhdr = 1;
405 break;
406 case NEXTHDR_DEST:
407 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
408 return offset;
409
410 if (found_rhdr)
411 return offset;
412
413 break;
414 default:
415 return offset;
416 }
417
418 offset += ipv6_optlen(exthdr);
419 *nexthdr = &exthdr->nexthdr;
420 exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
421 }
422
423 return offset;
424 }
425
426 static int mip6_rthdr_init_state(struct xfrm_state *x)
427 {
428 if (x->id.spi) {
429 printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
430 x->id.spi);
431 return -EINVAL;
432 }
433 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
434 printk(KERN_INFO "%s: state's mode is not %u: %u\n",
435 __FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
436 return -EINVAL;
437 }
438
439 x->props.header_len = sizeof(struct rt2_hdr);
440
441 return 0;
442 }
443
444 /*
445 * Do nothing about destroying since it has no specific operation for routing
446 * header type 2 unlike IPsec protocols.
447 */
448 static void mip6_rthdr_destroy(struct xfrm_state *x)
449 {
450 }
451
452 static struct xfrm_type mip6_rthdr_type =
453 {
454 .description = "MIP6RT",
455 .owner = THIS_MODULE,
456 .proto = IPPROTO_ROUTING,
457 .flags = XFRM_TYPE_NON_FRAGMENT,
458 .init_state = mip6_rthdr_init_state,
459 .destructor = mip6_rthdr_destroy,
460 .input = mip6_rthdr_input,
461 .output = mip6_rthdr_output,
462 .hdr_offset = mip6_rthdr_offset,
463 .remote_addr = mip6_xfrm_addr,
464 };
465
466 int __init mip6_init(void)
467 {
468 printk(KERN_INFO "Mobile IPv6\n");
469
470 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
471 printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __FUNCTION__);
472 goto mip6_destopt_xfrm_fail;
473 }
474 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
475 printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __FUNCTION__);
476 goto mip6_rthdr_xfrm_fail;
477 }
478 return 0;
479
480 mip6_rthdr_xfrm_fail:
481 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
482 mip6_destopt_xfrm_fail:
483 return -EAGAIN;
484 }
485
486 void __exit mip6_fini(void)
487 {
488 if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
489 printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
490 if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
491 printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);
492 }
Support for the Chinese Samsung S3C2440 based development boards