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 net_dbg_ratelimited("mip6: MH message too short: %d vs >=%d\n",
102 mip6_mh_len(mh
->ip6mh_type
));
103 mip6_param_prob(skb
, 0, offsetof(struct ip6_mh
, ip6mh_hdrlen
) +
104 skb_network_header_len(skb
));
108 if (mh
->ip6mh_proto
!= IPPROTO_NONE
) {
109 net_dbg_ratelimited("mip6: MH invalid payload proto = %d\n",
111 mip6_param_prob(skb
, 0, offsetof(struct ip6_mh
, ip6mh_proto
) +
112 skb_network_header_len(skb
));
119 struct mip6_report_rate_limiter
{
127 static struct mip6_report_rate_limiter mip6_report_rl
= {
128 .lock
= __SPIN_LOCK_UNLOCKED(mip6_report_rl
.lock
)
131 static int mip6_destopt_input(struct xfrm_state
*x
, struct sk_buff
*skb
)
133 const struct ipv6hdr
*iph
= ipv6_hdr(skb
);
134 struct ipv6_destopt_hdr
*destopt
= (struct ipv6_destopt_hdr
*)skb
->data
;
135 int err
= destopt
->nexthdr
;
138 if (!ipv6_addr_equal(&iph
->saddr
, (struct in6_addr
*)x
->coaddr
) &&
139 !ipv6_addr_any((struct in6_addr
*)x
->coaddr
))
141 spin_unlock(&x
->lock
);
146 /* Destination Option Header is inserted.
147 * IP Header's src address is replaced with Home Address Option in
148 * Destination Option Header.
150 static int mip6_destopt_output(struct xfrm_state
*x
, struct sk_buff
*skb
)
153 struct ipv6_destopt_hdr
*dstopt
;
154 struct ipv6_destopt_hao
*hao
;
158 skb_push(skb
, -skb_network_offset(skb
));
161 nexthdr
= *skb_mac_header(skb
);
162 *skb_mac_header(skb
) = IPPROTO_DSTOPTS
;
164 dstopt
= (struct ipv6_destopt_hdr
*)skb_transport_header(skb
);
165 dstopt
->nexthdr
= nexthdr
;
167 hao
= mip6_padn((char *)(dstopt
+ 1),
168 calc_padlen(sizeof(*dstopt
), 6));
170 hao
->type
= IPV6_TLV_HAO
;
171 BUILD_BUG_ON(sizeof(*hao
) != 18);
172 hao
->length
= sizeof(*hao
) - 2;
174 len
= ((char *)hao
- (char *)dstopt
) + sizeof(*hao
);
176 memcpy(&hao
->addr
, &iph
->saddr
, sizeof(hao
->addr
));
177 spin_lock_bh(&x
->lock
);
178 memcpy(&iph
->saddr
, x
->coaddr
, sizeof(iph
->saddr
));
179 spin_unlock_bh(&x
->lock
);
181 WARN_ON(len
!= x
->props
.header_len
);
182 dstopt
->hdrlen
= (x
->props
.header_len
>> 3) - 1;
187 static inline int mip6_report_rl_allow(ktime_t stamp
,
188 const struct in6_addr
*dst
,
189 const struct in6_addr
*src
, int iif
)
193 spin_lock_bh(&mip6_report_rl
.lock
);
194 if (!ktime_equal(mip6_report_rl
.stamp
, stamp
) ||
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
= stamp
;
199 mip6_report_rl
.iif
= iif
;
200 mip6_report_rl
.src
= *src
;
201 mip6_report_rl
.dst
= *dst
;
204 spin_unlock_bh(&mip6_report_rl
.lock
);
208 static int mip6_destopt_reject(struct xfrm_state
*x
, struct sk_buff
*skb
,
209 const struct flowi
*fl
)
211 struct net
*net
= xs_net(x
);
212 struct inet6_skb_parm
*opt
= (struct inet6_skb_parm
*)skb
->cb
;
213 const struct flowi6
*fl6
= &fl
->u
.ip6
;
214 struct ipv6_destopt_hao
*hao
= NULL
;
215 struct xfrm_selector sel
;
220 if (unlikely(fl6
->flowi6_proto
== IPPROTO_MH
&&
221 fl6
->fl6_mh_type
<= IP6_MH_TYPE_MAX
))
224 if (likely(opt
->dsthao
)) {
225 offset
= ipv6_find_tlv(skb
, opt
->dsthao
, IPV6_TLV_HAO
);
226 if (likely(offset
>= 0))
227 hao
= (struct ipv6_destopt_hao
*)
228 (skb_network_header(skb
) + offset
);
231 stamp
= skb_get_ktime(skb
);
233 if (!mip6_report_rl_allow(stamp
, &ipv6_hdr(skb
)->daddr
,
234 hao
? &hao
->addr
: &ipv6_hdr(skb
)->saddr
,
238 memset(&sel
, 0, sizeof(sel
));
239 memcpy(&sel
.daddr
, (xfrm_address_t
*)&ipv6_hdr(skb
)->daddr
,
241 sel
.prefixlen_d
= 128;
242 memcpy(&sel
.saddr
, (xfrm_address_t
*)&ipv6_hdr(skb
)->saddr
,
244 sel
.prefixlen_s
= 128;
245 sel
.family
= AF_INET6
;
246 sel
.proto
= fl6
->flowi6_proto
;
247 sel
.dport
= xfrm_flowi_dport(fl
, &fl6
->uli
);
249 sel
.dport_mask
= htons(~0);
250 sel
.sport
= xfrm_flowi_sport(fl
, &fl6
->uli
);
252 sel
.sport_mask
= htons(~0);
253 sel
.ifindex
= fl6
->flowi6_oif
;
255 err
= km_report(net
, IPPROTO_DSTOPTS
, &sel
,
256 (hao
? (xfrm_address_t
*)&hao
->addr
: NULL
));
262 static int mip6_destopt_offset(struct xfrm_state
*x
, struct sk_buff
*skb
,
265 u16 offset
= sizeof(struct ipv6hdr
);
266 struct ipv6_opt_hdr
*exthdr
=
267 (struct ipv6_opt_hdr
*)(ipv6_hdr(skb
) + 1);
268 const unsigned char *nh
= skb_network_header(skb
);
269 unsigned int packet_len
= skb_tail_pointer(skb
) -
270 skb_network_header(skb
);
273 *nexthdr
= &ipv6_hdr(skb
)->nexthdr
;
275 while (offset
+ 1 <= packet_len
) {
280 case NEXTHDR_ROUTING
:
285 * HAO MUST NOT appear more than once.
286 * XXX: It is better to try to find by the end of
287 * XXX: packet if HAO exists.
289 if (ipv6_find_tlv(skb
, offset
, IPV6_TLV_HAO
) >= 0) {
290 net_dbg_ratelimited("mip6: hao exists already, override\n");
302 offset
+= ipv6_optlen(exthdr
);
303 *nexthdr
= &exthdr
->nexthdr
;
304 exthdr
= (struct ipv6_opt_hdr
*)(nh
+ offset
);
310 static int mip6_destopt_init_state(struct xfrm_state
*x
)
313 pr_info("%s: spi is not 0: %u\n", __func__
, x
->id
.spi
);
316 if (x
->props
.mode
!= XFRM_MODE_ROUTEOPTIMIZATION
) {
317 pr_info("%s: state's mode is not %u: %u\n",
318 __func__
, XFRM_MODE_ROUTEOPTIMIZATION
, x
->props
.mode
);
322 x
->props
.header_len
= sizeof(struct ipv6_destopt_hdr
) +
323 calc_padlen(sizeof(struct ipv6_destopt_hdr
), 6) +
324 sizeof(struct ipv6_destopt_hao
);
325 WARN_ON(x
->props
.header_len
!= 24);
331 * Do nothing about destroying since it has no specific operation for
332 * destination options header unlike IPsec protocols.
334 static void mip6_destopt_destroy(struct xfrm_state
*x
)
338 static const struct xfrm_type mip6_destopt_type
= {
339 .description
= "MIP6DESTOPT",
340 .owner
= THIS_MODULE
,
341 .proto
= IPPROTO_DSTOPTS
,
342 .flags
= XFRM_TYPE_NON_FRAGMENT
| XFRM_TYPE_LOCAL_COADDR
,
343 .init_state
= mip6_destopt_init_state
,
344 .destructor
= mip6_destopt_destroy
,
345 .input
= mip6_destopt_input
,
346 .output
= mip6_destopt_output
,
347 .reject
= mip6_destopt_reject
,
348 .hdr_offset
= mip6_destopt_offset
,
351 static int mip6_rthdr_input(struct xfrm_state
*x
, struct sk_buff
*skb
)
353 const struct ipv6hdr
*iph
= ipv6_hdr(skb
);
354 struct rt2_hdr
*rt2
= (struct rt2_hdr
*)skb
->data
;
355 int err
= rt2
->rt_hdr
.nexthdr
;
358 if (!ipv6_addr_equal(&iph
->daddr
, (struct in6_addr
*)x
->coaddr
) &&
359 !ipv6_addr_any((struct in6_addr
*)x
->coaddr
))
361 spin_unlock(&x
->lock
);
366 /* Routing Header type 2 is inserted.
367 * IP Header's dst address is replaced with Routing Header's Home Address.
369 static int mip6_rthdr_output(struct xfrm_state
*x
, struct sk_buff
*skb
)
375 skb_push(skb
, -skb_network_offset(skb
));
378 nexthdr
= *skb_mac_header(skb
);
379 *skb_mac_header(skb
) = IPPROTO_ROUTING
;
381 rt2
= (struct rt2_hdr
*)skb_transport_header(skb
);
382 rt2
->rt_hdr
.nexthdr
= nexthdr
;
383 rt2
->rt_hdr
.hdrlen
= (x
->props
.header_len
>> 3) - 1;
384 rt2
->rt_hdr
.type
= IPV6_SRCRT_TYPE_2
;
385 rt2
->rt_hdr
.segments_left
= 1;
386 memset(&rt2
->reserved
, 0, sizeof(rt2
->reserved
));
388 WARN_ON(rt2
->rt_hdr
.hdrlen
!= 2);
390 memcpy(&rt2
->addr
, &iph
->daddr
, sizeof(rt2
->addr
));
391 spin_lock_bh(&x
->lock
);
392 memcpy(&iph
->daddr
, x
->coaddr
, sizeof(iph
->daddr
));
393 spin_unlock_bh(&x
->lock
);
398 static int mip6_rthdr_offset(struct xfrm_state
*x
, struct sk_buff
*skb
,
401 u16 offset
= sizeof(struct ipv6hdr
);
402 struct ipv6_opt_hdr
*exthdr
=
403 (struct ipv6_opt_hdr
*)(ipv6_hdr(skb
) + 1);
404 const unsigned char *nh
= skb_network_header(skb
);
405 unsigned int packet_len
= skb_tail_pointer(skb
) -
406 skb_network_header(skb
);
409 *nexthdr
= &ipv6_hdr(skb
)->nexthdr
;
411 while (offset
+ 1 <= packet_len
) {
416 case NEXTHDR_ROUTING
:
417 if (offset
+ 3 <= packet_len
) {
418 struct ipv6_rt_hdr
*rt
;
419 rt
= (struct ipv6_rt_hdr
*)(nh
+ offset
);
426 if (ipv6_find_tlv(skb
, offset
, IPV6_TLV_HAO
) >= 0)
437 offset
+= ipv6_optlen(exthdr
);
438 *nexthdr
= &exthdr
->nexthdr
;
439 exthdr
= (struct ipv6_opt_hdr
*)(nh
+ offset
);
445 static int mip6_rthdr_init_state(struct xfrm_state
*x
)
448 pr_info("%s: spi is not 0: %u\n", __func__
, x
->id
.spi
);
451 if (x
->props
.mode
!= XFRM_MODE_ROUTEOPTIMIZATION
) {
452 pr_info("%s: state's mode is not %u: %u\n",
453 __func__
, XFRM_MODE_ROUTEOPTIMIZATION
, x
->props
.mode
);
457 x
->props
.header_len
= sizeof(struct rt2_hdr
);
463 * Do nothing about destroying since it has no specific operation for routing
464 * header type 2 unlike IPsec protocols.
466 static void mip6_rthdr_destroy(struct xfrm_state
*x
)
470 static const struct xfrm_type mip6_rthdr_type
= {
471 .description
= "MIP6RT",
472 .owner
= THIS_MODULE
,
473 .proto
= IPPROTO_ROUTING
,
474 .flags
= XFRM_TYPE_NON_FRAGMENT
| XFRM_TYPE_REMOTE_COADDR
,
475 .init_state
= mip6_rthdr_init_state
,
476 .destructor
= mip6_rthdr_destroy
,
477 .input
= mip6_rthdr_input
,
478 .output
= mip6_rthdr_output
,
479 .hdr_offset
= mip6_rthdr_offset
,
482 static int __init
mip6_init(void)
484 pr_info("Mobile IPv6\n");
486 if (xfrm_register_type(&mip6_destopt_type
, AF_INET6
) < 0) {
487 pr_info("%s: can't add xfrm type(destopt)\n", __func__
);
488 goto mip6_destopt_xfrm_fail
;
490 if (xfrm_register_type(&mip6_rthdr_type
, AF_INET6
) < 0) {
491 pr_info("%s: can't add xfrm type(rthdr)\n", __func__
);
492 goto mip6_rthdr_xfrm_fail
;
494 if (rawv6_mh_filter_register(mip6_mh_filter
) < 0) {
495 pr_info("%s: can't add rawv6 mh filter\n", __func__
);
496 goto mip6_rawv6_mh_fail
;
503 xfrm_unregister_type(&mip6_rthdr_type
, AF_INET6
);
504 mip6_rthdr_xfrm_fail
:
505 xfrm_unregister_type(&mip6_destopt_type
, AF_INET6
);
506 mip6_destopt_xfrm_fail
:
510 static void __exit
mip6_fini(void)
512 if (rawv6_mh_filter_unregister(mip6_mh_filter
) < 0)
513 pr_info("%s: can't remove rawv6 mh filter\n", __func__
);
514 if (xfrm_unregister_type(&mip6_rthdr_type
, AF_INET6
) < 0)
515 pr_info("%s: can't remove xfrm type(rthdr)\n", __func__
);
516 if (xfrm_unregister_type(&mip6_destopt_type
, AF_INET6
) < 0)
517 pr_info("%s: can't remove xfrm type(destopt)\n", __func__
);
520 module_init(mip6_init
);
521 module_exit(mip6_fini
);
523 MODULE_LICENSE("GPL");
524 MODULE_ALIAS_XFRM_TYPE(AF_INET6
, XFRM_PROTO_DSTOPTS
);
525 MODULE_ALIAS_XFRM_TYPE(AF_INET6
, XFRM_PROTO_ROUTING
);