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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C)2003-2006 Helsinki University of Technology
4 * Copyright (C)2003-2006 USAGI/WIDE Project
5 */
6/*
7 * Authors:
8 * Noriaki TAKAMIYA @USAGI
9 * Masahide NAKAMURA @USAGI
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/module.h>
15#include <linux/skbuff.h>
16#include <linux/time.h>
17#include <linux/ipv6.h>
18#include <linux/icmpv6.h>
19#include <net/sock.h>
20#include <net/ipv6.h>
21#include <net/ip6_checksum.h>
22#include <net/rawv6.h>
23#include <net/xfrm.h>
24#include <net/mip6.h>
25
26static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
27{
28 return (n - len + 16) & 0x7;
29}
30
31static inline void *mip6_padn(__u8 *data, __u8 padlen)
32{
33 if (!data)
34 return NULL;
35 if (padlen == 1) {
36 data[0] = IPV6_TLV_PAD1;
37 } else if (padlen > 1) {
38 data[0] = IPV6_TLV_PADN;
39 data[1] = padlen - 2;
40 if (padlen > 2)
41 memset(data+2, 0, data[1]);
42 }
43 return data + padlen;
44}
45
46static inline void mip6_param_prob(struct sk_buff *skb, u8 code, int pos)
47{
48 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
49}
50
51static int mip6_mh_len(int type)
52{
53 int len = 0;
54
55 switch (type) {
56 case IP6_MH_TYPE_BRR:
57 len = 0;
58 break;
59 case IP6_MH_TYPE_HOTI:
60 case IP6_MH_TYPE_COTI:
61 case IP6_MH_TYPE_BU:
62 case IP6_MH_TYPE_BACK:
63 len = 1;
64 break;
65 case IP6_MH_TYPE_HOT:
66 case IP6_MH_TYPE_COT:
67 case IP6_MH_TYPE_BERROR:
68 len = 2;
69 break;
70 }
71 return len;
72}
73
74static int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
75{
76 struct ip6_mh _hdr;
77 const struct ip6_mh *mh;
78
79 mh = skb_header_pointer(skb, skb_transport_offset(skb),
80 sizeof(_hdr), &_hdr);
81 if (!mh)
82 return -1;
83
84 if (((mh->ip6mh_hdrlen + 1) << 3) > skb->len)
85 return -1;
86
87 if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
88 net_dbg_ratelimited("mip6: MH message too short: %d vs >=%d\n",
89 mh->ip6mh_hdrlen,
90 mip6_mh_len(mh->ip6mh_type));
91 mip6_param_prob(skb, 0, offsetof(struct ip6_mh, ip6mh_hdrlen) +
92 skb_network_header_len(skb));
93 return -1;
94 }
95
96 if (mh->ip6mh_proto != IPPROTO_NONE) {
97 net_dbg_ratelimited("mip6: MH invalid payload proto = %d\n",
98 mh->ip6mh_proto);
99 mip6_param_prob(skb, 0, offsetof(struct ip6_mh, ip6mh_proto) +
100 skb_network_header_len(skb));
101 return -1;
102 }
103
104 return 0;
105}
106
107struct mip6_report_rate_limiter {
108 spinlock_t lock;
109 ktime_t stamp;
110 int iif;
111 struct in6_addr src;
112 struct in6_addr dst;
113};
114
115static struct mip6_report_rate_limiter mip6_report_rl = {
116 .lock = __SPIN_LOCK_UNLOCKED(mip6_report_rl.lock)
117};
118
119static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
120{
121 const struct ipv6hdr *iph = ipv6_hdr(skb);
122 struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
123 int err = destopt->nexthdr;
124
125 spin_lock(&x->lock);
126 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
127 !ipv6_addr_any((struct in6_addr *)x->coaddr))
128 err = -ENOENT;
129 spin_unlock(&x->lock);
130
131 return err;
132}
133
134/* Destination Option Header is inserted.
135 * IP Header's src address is replaced with Home Address Option in
136 * Destination Option Header.
137 */
138static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
139{
140 struct ipv6hdr *iph;
141 struct ipv6_destopt_hdr *dstopt;
142 struct ipv6_destopt_hao *hao;
143 u8 nexthdr;
144 int len;
145
146 skb_push(skb, -skb_network_offset(skb));
147 iph = ipv6_hdr(skb);
148
149 nexthdr = *skb_mac_header(skb);
150 *skb_mac_header(skb) = IPPROTO_DSTOPTS;
151
152 dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
153 dstopt->nexthdr = nexthdr;
154
155 hao = mip6_padn((char *)(dstopt + 1),
156 calc_padlen(sizeof(*dstopt), 6));
157
158 hao->type = IPV6_TLV_HAO;
159 BUILD_BUG_ON(sizeof(*hao) != 18);
160 hao->length = sizeof(*hao) - 2;
161
162 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
163
164 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
165 spin_lock_bh(&x->lock);
166 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
167 spin_unlock_bh(&x->lock);
168
169 WARN_ON(len != x->props.header_len);
170 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
171
172 return 0;
173}
174
175static inline int mip6_report_rl_allow(ktime_t stamp,
176 const struct in6_addr *dst,
177 const struct in6_addr *src, int iif)
178{
179 int allow = 0;
180
181 spin_lock_bh(&mip6_report_rl.lock);
182 if (mip6_report_rl.stamp != stamp ||
183 mip6_report_rl.iif != iif ||
184 !ipv6_addr_equal(&mip6_report_rl.src, src) ||
185 !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
186 mip6_report_rl.stamp = stamp;
187 mip6_report_rl.iif = iif;
188 mip6_report_rl.src = *src;
189 mip6_report_rl.dst = *dst;
190 allow = 1;
191 }
192 spin_unlock_bh(&mip6_report_rl.lock);
193 return allow;
194}
195
196static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb,
197 const struct flowi *fl)
198{
199 struct net *net = xs_net(x);
200 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
201 const struct flowi6 *fl6 = &fl->u.ip6;
202 struct ipv6_destopt_hao *hao = NULL;
203 struct xfrm_selector sel;
204 int offset;
205 ktime_t stamp;
206 int err = 0;
207
208 if (unlikely(fl6->flowi6_proto == IPPROTO_MH &&
209 fl6->fl6_mh_type <= IP6_MH_TYPE_MAX))
210 goto out;
211
212 if (likely(opt->dsthao)) {
213 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
214 if (likely(offset >= 0))
215 hao = (struct ipv6_destopt_hao *)
216 (skb_network_header(skb) + offset);
217 }
218
219 stamp = skb_get_ktime(skb);
220
221 if (!mip6_report_rl_allow(stamp, &ipv6_hdr(skb)->daddr,
222 hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
223 opt->iif))
224 goto out;
225
226 memset(&sel, 0, sizeof(sel));
227 memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
228 sizeof(sel.daddr));
229 sel.prefixlen_d = 128;
230 memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
231 sizeof(sel.saddr));
232 sel.prefixlen_s = 128;
233 sel.family = AF_INET6;
234 sel.proto = fl6->flowi6_proto;
235 sel.dport = xfrm_flowi_dport(fl, &fl6->uli);
236 if (sel.dport)
237 sel.dport_mask = htons(~0);
238 sel.sport = xfrm_flowi_sport(fl, &fl6->uli);
239 if (sel.sport)
240 sel.sport_mask = htons(~0);
241 sel.ifindex = fl6->flowi6_oif;
242
243 err = km_report(net, IPPROTO_DSTOPTS, &sel,
244 (hao ? (xfrm_address_t *)&hao->addr : NULL));
245
246 out:
247 return err;
248}
249
250static int mip6_destopt_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
251{
252 if (x->id.spi) {
253 NL_SET_ERR_MSG(extack, "SPI must be 0");
254 return -EINVAL;
255 }
256 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
257 NL_SET_ERR_MSG(extack, "XFRM mode must be XFRM_MODE_ROUTEOPTIMIZATION");
258 return -EINVAL;
259 }
260
261 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
262 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
263 sizeof(struct ipv6_destopt_hao);
264 WARN_ON(x->props.header_len != 24);
265
266 return 0;
267}
268
269/*
270 * Do nothing about destroying since it has no specific operation for
271 * destination options header unlike IPsec protocols.
272 */
273static void mip6_destopt_destroy(struct xfrm_state *x)
274{
275}
276
277static const struct xfrm_type mip6_destopt_type = {
278 .owner = THIS_MODULE,
279 .proto = IPPROTO_DSTOPTS,
280 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_LOCAL_COADDR,
281 .init_state = mip6_destopt_init_state,
282 .destructor = mip6_destopt_destroy,
283 .input = mip6_destopt_input,
284 .output = mip6_destopt_output,
285 .reject = mip6_destopt_reject,
286};
287
288static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
289{
290 const struct ipv6hdr *iph = ipv6_hdr(skb);
291 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
292 int err = rt2->rt_hdr.nexthdr;
293
294 spin_lock(&x->lock);
295 if (!ipv6_addr_equal(&iph->daddr, (struct in6_addr *)x->coaddr) &&
296 !ipv6_addr_any((struct in6_addr *)x->coaddr))
297 err = -ENOENT;
298 spin_unlock(&x->lock);
299
300 return err;
301}
302
303/* Routing Header type 2 is inserted.
304 * IP Header's dst address is replaced with Routing Header's Home Address.
305 */
306static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
307{
308 struct ipv6hdr *iph;
309 struct rt2_hdr *rt2;
310 u8 nexthdr;
311
312 skb_push(skb, -skb_network_offset(skb));
313 iph = ipv6_hdr(skb);
314
315 nexthdr = *skb_mac_header(skb);
316 *skb_mac_header(skb) = IPPROTO_ROUTING;
317
318 rt2 = (struct rt2_hdr *)skb_transport_header(skb);
319 rt2->rt_hdr.nexthdr = nexthdr;
320 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
321 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
322 rt2->rt_hdr.segments_left = 1;
323 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
324
325 WARN_ON(rt2->rt_hdr.hdrlen != 2);
326
327 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
328 spin_lock_bh(&x->lock);
329 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
330 spin_unlock_bh(&x->lock);
331
332 return 0;
333}
334
335static int mip6_rthdr_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack)
336{
337 if (x->id.spi) {
338 NL_SET_ERR_MSG(extack, "SPI must be 0");
339 return -EINVAL;
340 }
341 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
342 NL_SET_ERR_MSG(extack, "XFRM mode must be XFRM_MODE_ROUTEOPTIMIZATION");
343 return -EINVAL;
344 }
345
346 x->props.header_len = sizeof(struct rt2_hdr);
347
348 return 0;
349}
350
351/*
352 * Do nothing about destroying since it has no specific operation for routing
353 * header type 2 unlike IPsec protocols.
354 */
355static void mip6_rthdr_destroy(struct xfrm_state *x)
356{
357}
358
359static const struct xfrm_type mip6_rthdr_type = {
360 .owner = THIS_MODULE,
361 .proto = IPPROTO_ROUTING,
362 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_REMOTE_COADDR,
363 .init_state = mip6_rthdr_init_state,
364 .destructor = mip6_rthdr_destroy,
365 .input = mip6_rthdr_input,
366 .output = mip6_rthdr_output,
367};
368
369static int __init mip6_init(void)
370{
371 pr_info("Mobile IPv6\n");
372
373 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
374 pr_info("%s: can't add xfrm type(destopt)\n", __func__);
375 goto mip6_destopt_xfrm_fail;
376 }
377 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
378 pr_info("%s: can't add xfrm type(rthdr)\n", __func__);
379 goto mip6_rthdr_xfrm_fail;
380 }
381 if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
382 pr_info("%s: can't add rawv6 mh filter\n", __func__);
383 goto mip6_rawv6_mh_fail;
384 }
385
386
387 return 0;
388
389 mip6_rawv6_mh_fail:
390 xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
391 mip6_rthdr_xfrm_fail:
392 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
393 mip6_destopt_xfrm_fail:
394 return -EAGAIN;
395}
396
397static void __exit mip6_fini(void)
398{
399 if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
400 pr_info("%s: can't remove rawv6 mh filter\n", __func__);
401 xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
402 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
403}
404
405module_init(mip6_init);
406module_exit(mip6_fini);
407
408MODULE_DESCRIPTION("IPv6 Mobility driver");
409MODULE_LICENSE("GPL");
410MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
411MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);
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, see <http://www.gnu.org/licenses/>.
17 */
18/*
19 * Authors:
20 * Noriaki TAKAMIYA @USAGI
21 * Masahide NAKAMURA @USAGI
22 */
23
24#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25
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>
31#include <net/sock.h>
32#include <net/ipv6.h>
33#include <net/ip6_checksum.h>
34#include <net/rawv6.h>
35#include <net/xfrm.h>
36#include <net/mip6.h>
37
38static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
39{
40 return (n - len + 16) & 0x7;
41}
42
43static inline void *mip6_padn(__u8 *data, __u8 padlen)
44{
45 if (!data)
46 return NULL;
47 if (padlen == 1) {
48 data[0] = IPV6_TLV_PAD1;
49 } else if (padlen > 1) {
50 data[0] = IPV6_TLV_PADN;
51 data[1] = padlen - 2;
52 if (padlen > 2)
53 memset(data+2, 0, data[1]);
54 }
55 return data + padlen;
56}
57
58static inline void mip6_param_prob(struct sk_buff *skb, u8 code, int pos)
59{
60 icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
61}
62
63static int mip6_mh_len(int type)
64{
65 int len = 0;
66
67 switch (type) {
68 case IP6_MH_TYPE_BRR:
69 len = 0;
70 break;
71 case IP6_MH_TYPE_HOTI:
72 case IP6_MH_TYPE_COTI:
73 case IP6_MH_TYPE_BU:
74 case IP6_MH_TYPE_BACK:
75 len = 1;
76 break;
77 case IP6_MH_TYPE_HOT:
78 case IP6_MH_TYPE_COT:
79 case IP6_MH_TYPE_BERROR:
80 len = 2;
81 break;
82 }
83 return len;
84}
85
86static int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
87{
88 struct ip6_mh _hdr;
89 const struct ip6_mh *mh;
90
91 mh = skb_header_pointer(skb, skb_transport_offset(skb),
92 sizeof(_hdr), &_hdr);
93 if (!mh)
94 return -1;
95
96 if (((mh->ip6mh_hdrlen + 1) << 3) > skb->len)
97 return -1;
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, offsetof(struct ip6_mh, ip6mh_hdrlen) +
103 skb_network_header_len(skb));
104 return -1;
105 }
106
107 if (mh->ip6mh_proto != IPPROTO_NONE) {
108 LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
109 mh->ip6mh_proto);
110 mip6_param_prob(skb, 0, offsetof(struct ip6_mh, ip6mh_proto) +
111 skb_network_header_len(skb));
112 return -1;
113 }
114
115 return 0;
116}
117
118struct mip6_report_rate_limiter {
119 spinlock_t lock;
120 struct timeval stamp;
121 int iif;
122 struct in6_addr src;
123 struct in6_addr dst;
124};
125
126static struct mip6_report_rate_limiter mip6_report_rl = {
127 .lock = __SPIN_LOCK_UNLOCKED(mip6_report_rl.lock)
128};
129
130static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
131{
132 const struct ipv6hdr *iph = ipv6_hdr(skb);
133 struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
134 int err = destopt->nexthdr;
135
136 spin_lock(&x->lock);
137 if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
138 !ipv6_addr_any((struct in6_addr *)x->coaddr))
139 err = -ENOENT;
140 spin_unlock(&x->lock);
141
142 return err;
143}
144
145/* Destination Option Header is inserted.
146 * IP Header's src address is replaced with Home Address Option in
147 * Destination Option Header.
148 */
149static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
150{
151 struct ipv6hdr *iph;
152 struct ipv6_destopt_hdr *dstopt;
153 struct ipv6_destopt_hao *hao;
154 u8 nexthdr;
155 int len;
156
157 skb_push(skb, -skb_network_offset(skb));
158 iph = ipv6_hdr(skb);
159
160 nexthdr = *skb_mac_header(skb);
161 *skb_mac_header(skb) = IPPROTO_DSTOPTS;
162
163 dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
164 dstopt->nexthdr = nexthdr;
165
166 hao = mip6_padn((char *)(dstopt + 1),
167 calc_padlen(sizeof(*dstopt), 6));
168
169 hao->type = IPV6_TLV_HAO;
170 BUILD_BUG_ON(sizeof(*hao) != 18);
171 hao->length = sizeof(*hao) - 2;
172
173 len = ((char *)hao - (char *)dstopt) + sizeof(*hao);
174
175 memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
176 spin_lock_bh(&x->lock);
177 memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
178 spin_unlock_bh(&x->lock);
179
180 WARN_ON(len != x->props.header_len);
181 dstopt->hdrlen = (x->props.header_len >> 3) - 1;
182
183 return 0;
184}
185
186static inline int mip6_report_rl_allow(struct timeval *stamp,
187 const struct in6_addr *dst,
188 const struct in6_addr *src, int iif)
189{
190 int allow = 0;
191
192 spin_lock_bh(&mip6_report_rl.lock);
193 if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
194 mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
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.tv_sec = stamp->tv_sec;
199 mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
200 mip6_report_rl.iif = iif;
201 mip6_report_rl.src = *src;
202 mip6_report_rl.dst = *dst;
203 allow = 1;
204 }
205 spin_unlock_bh(&mip6_report_rl.lock);
206 return allow;
207}
208
209static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb,
210 const struct flowi *fl)
211{
212 struct net *net = xs_net(x);
213 struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
214 const struct flowi6 *fl6 = &fl->u.ip6;
215 struct ipv6_destopt_hao *hao = NULL;
216 struct xfrm_selector sel;
217 int offset;
218 struct timeval stamp;
219 int err = 0;
220
221 if (unlikely(fl6->flowi6_proto == IPPROTO_MH &&
222 fl6->fl6_mh_type <= IP6_MH_TYPE_MAX))
223 goto out;
224
225 if (likely(opt->dsthao)) {
226 offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
227 if (likely(offset >= 0))
228 hao = (struct ipv6_destopt_hao *)
229 (skb_network_header(skb) + offset);
230 }
231
232 skb_get_timestamp(skb, &stamp);
233
234 if (!mip6_report_rl_allow(&stamp, &ipv6_hdr(skb)->daddr,
235 hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
236 opt->iif))
237 goto out;
238
239 memset(&sel, 0, sizeof(sel));
240 memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
241 sizeof(sel.daddr));
242 sel.prefixlen_d = 128;
243 memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
244 sizeof(sel.saddr));
245 sel.prefixlen_s = 128;
246 sel.family = AF_INET6;
247 sel.proto = fl6->flowi6_proto;
248 sel.dport = xfrm_flowi_dport(fl, &fl6->uli);
249 if (sel.dport)
250 sel.dport_mask = htons(~0);
251 sel.sport = xfrm_flowi_sport(fl, &fl6->uli);
252 if (sel.sport)
253 sel.sport_mask = htons(~0);
254 sel.ifindex = fl6->flowi6_oif;
255
256 err = km_report(net, IPPROTO_DSTOPTS, &sel,
257 (hao ? (xfrm_address_t *)&hao->addr : NULL));
258
259 out:
260 return err;
261}
262
263static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
264 u8 **nexthdr)
265{
266 u16 offset = sizeof(struct ipv6hdr);
267 struct ipv6_opt_hdr *exthdr =
268 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
269 const unsigned char *nh = skb_network_header(skb);
270 unsigned int packet_len = skb_tail_pointer(skb) -
271 skb_network_header(skb);
272 int found_rhdr = 0;
273
274 *nexthdr = &ipv6_hdr(skb)->nexthdr;
275
276 while (offset + 1 <= packet_len) {
277
278 switch (**nexthdr) {
279 case NEXTHDR_HOP:
280 break;
281 case NEXTHDR_ROUTING:
282 found_rhdr = 1;
283 break;
284 case NEXTHDR_DEST:
285 /*
286 * HAO MUST NOT appear more than once.
287 * XXX: It is better to try to find by the end of
288 * XXX: packet if HAO exists.
289 */
290 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
291 LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
292 return offset;
293 }
294
295 if (found_rhdr)
296 return offset;
297
298 break;
299 default:
300 return offset;
301 }
302
303 offset += ipv6_optlen(exthdr);
304 *nexthdr = &exthdr->nexthdr;
305 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
306 }
307
308 return offset;
309}
310
311static int mip6_destopt_init_state(struct xfrm_state *x)
312{
313 if (x->id.spi) {
314 pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
315 return -EINVAL;
316 }
317 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
318 pr_info("%s: state's mode is not %u: %u\n",
319 __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
320 return -EINVAL;
321 }
322
323 x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
324 calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
325 sizeof(struct ipv6_destopt_hao);
326 WARN_ON(x->props.header_len != 24);
327
328 return 0;
329}
330
331/*
332 * Do nothing about destroying since it has no specific operation for
333 * destination options header unlike IPsec protocols.
334 */
335static void mip6_destopt_destroy(struct xfrm_state *x)
336{
337}
338
339static const struct xfrm_type mip6_destopt_type =
340{
341 .description = "MIP6DESTOPT",
342 .owner = THIS_MODULE,
343 .proto = IPPROTO_DSTOPTS,
344 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_LOCAL_COADDR,
345 .init_state = mip6_destopt_init_state,
346 .destructor = mip6_destopt_destroy,
347 .input = mip6_destopt_input,
348 .output = mip6_destopt_output,
349 .reject = mip6_destopt_reject,
350 .hdr_offset = mip6_destopt_offset,
351};
352
353static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
354{
355 const struct ipv6hdr *iph = ipv6_hdr(skb);
356 struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
357 int err = rt2->rt_hdr.nexthdr;
358
359 spin_lock(&x->lock);
360 if (!ipv6_addr_equal(&iph->daddr, (struct in6_addr *)x->coaddr) &&
361 !ipv6_addr_any((struct in6_addr *)x->coaddr))
362 err = -ENOENT;
363 spin_unlock(&x->lock);
364
365 return err;
366}
367
368/* Routing Header type 2 is inserted.
369 * IP Header's dst address is replaced with Routing Header's Home Address.
370 */
371static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
372{
373 struct ipv6hdr *iph;
374 struct rt2_hdr *rt2;
375 u8 nexthdr;
376
377 skb_push(skb, -skb_network_offset(skb));
378 iph = ipv6_hdr(skb);
379
380 nexthdr = *skb_mac_header(skb);
381 *skb_mac_header(skb) = IPPROTO_ROUTING;
382
383 rt2 = (struct rt2_hdr *)skb_transport_header(skb);
384 rt2->rt_hdr.nexthdr = nexthdr;
385 rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
386 rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
387 rt2->rt_hdr.segments_left = 1;
388 memset(&rt2->reserved, 0, sizeof(rt2->reserved));
389
390 WARN_ON(rt2->rt_hdr.hdrlen != 2);
391
392 memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
393 spin_lock_bh(&x->lock);
394 memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
395 spin_unlock_bh(&x->lock);
396
397 return 0;
398}
399
400static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
401 u8 **nexthdr)
402{
403 u16 offset = sizeof(struct ipv6hdr);
404 struct ipv6_opt_hdr *exthdr =
405 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
406 const unsigned char *nh = skb_network_header(skb);
407 unsigned int packet_len = skb_tail_pointer(skb) -
408 skb_network_header(skb);
409 int found_rhdr = 0;
410
411 *nexthdr = &ipv6_hdr(skb)->nexthdr;
412
413 while (offset + 1 <= packet_len) {
414
415 switch (**nexthdr) {
416 case NEXTHDR_HOP:
417 break;
418 case NEXTHDR_ROUTING:
419 if (offset + 3 <= packet_len) {
420 struct ipv6_rt_hdr *rt;
421 rt = (struct ipv6_rt_hdr *)(nh + offset);
422 if (rt->type != 0)
423 return offset;
424 }
425 found_rhdr = 1;
426 break;
427 case NEXTHDR_DEST:
428 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
429 return offset;
430
431 if (found_rhdr)
432 return offset;
433
434 break;
435 default:
436 return offset;
437 }
438
439 offset += ipv6_optlen(exthdr);
440 *nexthdr = &exthdr->nexthdr;
441 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
442 }
443
444 return offset;
445}
446
447static int mip6_rthdr_init_state(struct xfrm_state *x)
448{
449 if (x->id.spi) {
450 pr_info("%s: spi is not 0: %u\n", __func__, x->id.spi);
451 return -EINVAL;
452 }
453 if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
454 pr_info("%s: state's mode is not %u: %u\n",
455 __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
456 return -EINVAL;
457 }
458
459 x->props.header_len = sizeof(struct rt2_hdr);
460
461 return 0;
462}
463
464/*
465 * Do nothing about destroying since it has no specific operation for routing
466 * header type 2 unlike IPsec protocols.
467 */
468static void mip6_rthdr_destroy(struct xfrm_state *x)
469{
470}
471
472static const struct xfrm_type mip6_rthdr_type =
473{
474 .description = "MIP6RT",
475 .owner = THIS_MODULE,
476 .proto = IPPROTO_ROUTING,
477 .flags = XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_REMOTE_COADDR,
478 .init_state = mip6_rthdr_init_state,
479 .destructor = mip6_rthdr_destroy,
480 .input = mip6_rthdr_input,
481 .output = mip6_rthdr_output,
482 .hdr_offset = mip6_rthdr_offset,
483};
484
485static int __init mip6_init(void)
486{
487 pr_info("Mobile IPv6\n");
488
489 if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
490 pr_info("%s: can't add xfrm type(destopt)\n", __func__);
491 goto mip6_destopt_xfrm_fail;
492 }
493 if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
494 pr_info("%s: can't add xfrm type(rthdr)\n", __func__);
495 goto mip6_rthdr_xfrm_fail;
496 }
497 if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
498 pr_info("%s: can't add rawv6 mh filter\n", __func__);
499 goto mip6_rawv6_mh_fail;
500 }
501
502
503 return 0;
504
505 mip6_rawv6_mh_fail:
506 xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
507 mip6_rthdr_xfrm_fail:
508 xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
509 mip6_destopt_xfrm_fail:
510 return -EAGAIN;
511}
512
513static void __exit mip6_fini(void)
514{
515 if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
516 pr_info("%s: can't remove rawv6 mh filter\n", __func__);
517 if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
518 pr_info("%s: can't remove xfrm type(rthdr)\n", __func__);
519 if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
520 pr_info("%s: can't remove xfrm type(destopt)\n", __func__);
521}
522
523module_init(mip6_init);
524module_exit(mip6_fini);
525
526MODULE_LICENSE("GPL");
527MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
528MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);