blob: 82e27b80d07d3d060112eb873d7b0a9774853cba [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * xfrm6_policy.c: based on xfrm4_policy.c
3 *
4 * Authors:
5 * Mitsuru KANDA @USAGI
6 * Kazunori MIYAZAWA @USAGI
7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8 * IPv6 support
9 * YOSHIFUJI Hideaki
10 * Split up af-specific portion
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090011 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 */
13
Herbert Xuaabc9762005-05-03 16:27:10 -070014#include <linux/compiler.h>
Herbert Xuaabc9762005-05-03 16:27:10 -070015#include <linux/netdevice.h>
16#include <net/addrconf.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <net/xfrm.h>
18#include <net/ip.h>
19#include <net/ipv6.h>
20#include <net/ip6_route.h>
Masahide NAKAMURA59fbb3a62007-06-26 23:56:32 -070021#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
Masahide NAKAMURA2ce42722006-08-23 20:39:03 -070022#include <net/mip6.h>
23#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
25static struct dst_ops xfrm6_dst_ops;
26static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
27
Ville Nuorvala42513202006-10-16 22:10:05 -070028static int xfrm6_dst_lookup(struct xfrm_dst **xdst, struct flowi *fl)
Linus Torvalds1da177e2005-04-16 15:20:36 -070029{
Ville Nuorvala42513202006-10-16 22:10:05 -070030 struct dst_entry *dst = ip6_route_output(NULL, fl);
31 int err = dst->error;
32 if (!err)
33 *xdst = (struct xfrm_dst *) dst;
34 else
35 dst_release(dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -070036 return err;
37}
38
Patrick McHardya1e59ab2006-09-19 12:57:34 -070039static int xfrm6_get_saddr(xfrm_address_t *saddr, xfrm_address_t *daddr)
40{
41 struct rt6_info *rt;
42 struct flowi fl_tunnel = {
43 .nl_u = {
44 .ip6_u = {
45 .daddr = *(struct in6_addr *)&daddr->a6,
46 },
47 },
48 };
49
50 if (!xfrm6_dst_lookup((struct xfrm_dst **)&rt, &fl_tunnel)) {
51 ipv6_get_saddr(&rt->u.dst, (struct in6_addr *)&daddr->a6,
52 (struct in6_addr *)&saddr->a6);
53 dst_release(&rt->u.dst);
54 return 0;
55 }
56 return -EHOSTUNREACH;
57}
58
Linus Torvalds1da177e2005-04-16 15:20:36 -070059static struct dst_entry *
60__xfrm6_find_bundle(struct flowi *fl, struct xfrm_policy *policy)
61{
62 struct dst_entry *dst;
63
64 /* Still not clear if we should set fl->fl6_{src,dst}... */
65 read_lock_bh(&policy->lock);
66 for (dst = policy->bundles; dst; dst = dst->next) {
67 struct xfrm_dst *xdst = (struct xfrm_dst*)dst;
68 struct in6_addr fl_dst_prefix, fl_src_prefix;
69
70 ipv6_addr_prefix(&fl_dst_prefix,
71 &fl->fl6_dst,
72 xdst->u.rt6.rt6i_dst.plen);
73 ipv6_addr_prefix(&fl_src_prefix,
74 &fl->fl6_src,
75 xdst->u.rt6.rt6i_src.plen);
76 if (ipv6_addr_equal(&xdst->u.rt6.rt6i_dst.addr, &fl_dst_prefix) &&
77 ipv6_addr_equal(&xdst->u.rt6.rt6i_src.addr, &fl_src_prefix) &&
Venkat Yekkirala5b368e62006-10-05 15:42:18 -050078 xfrm_bundle_ok(policy, xdst, fl, AF_INET6,
Masahide NAKAMURAe53820d2006-08-23 19:12:01 -070079 (xdst->u.rt6.rt6i_dst.plen != 128 ||
80 xdst->u.rt6.rt6i_src.plen != 128))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 dst_clone(dst);
82 break;
83 }
84 }
85 read_unlock_bh(&policy->lock);
86 return dst;
87}
88
Masahide NAKAMURA99505a82006-08-23 18:10:33 -070089static inline struct in6_addr*
90__xfrm6_bundle_addr_remote(struct xfrm_state *x, struct in6_addr *addr)
91{
92 return (x->type->remote_addr) ?
93 (struct in6_addr*)x->type->remote_addr(x, (xfrm_address_t *)addr) :
94 (struct in6_addr*)&x->id.daddr;
95}
96
97static inline struct in6_addr*
98__xfrm6_bundle_addr_local(struct xfrm_state *x, struct in6_addr *addr)
99{
100 return (x->type->local_addr) ?
101 (struct in6_addr*)x->type->local_addr(x, (xfrm_address_t *)addr) :
102 (struct in6_addr*)&x->props.saddr;
103}
104
Masahide NAKAMURA1b5c2292006-08-23 18:11:50 -0700105static inline void
106__xfrm6_bundle_len_inc(int *len, int *nflen, struct xfrm_state *x)
107{
108 if (x->type->flags & XFRM_TYPE_NON_FRAGMENT)
109 *nflen += x->props.header_len;
110 else
111 *len += x->props.header_len;
112}
113
114static inline void
115__xfrm6_bundle_len_dec(int *len, int *nflen, struct xfrm_state *x)
116{
117 if (x->type->flags & XFRM_TYPE_NON_FRAGMENT)
118 *nflen -= x->props.header_len;
119 else
120 *len -= x->props.header_len;
121}
122
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123/* Allocate chain of dst_entry's, attach known xfrm's, calculate
124 * all the metrics... Shortly, bundle a bundle.
125 */
126
127static int
128__xfrm6_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx,
129 struct flowi *fl, struct dst_entry **dst_p)
130{
131 struct dst_entry *dst, *dst_prev;
132 struct rt6_info *rt0 = (struct rt6_info*)(*dst_p);
133 struct rt6_info *rt = rt0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 struct flowi fl_tunnel = {
135 .nl_u = {
136 .ip6_u = {
Miika Komuc82f9632007-02-06 14:27:02 -0800137 .saddr = fl->fl6_src,
138 .daddr = fl->fl6_dst,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 }
140 }
141 };
142 int i;
143 int err = 0;
144 int header_len = 0;
Masahide NAKAMURA1b5c2292006-08-23 18:11:50 -0700145 int nfheader_len = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 int trailer_len = 0;
147
148 dst = dst_prev = NULL;
149 dst_hold(&rt->u.dst);
150
151 for (i = 0; i < nx; i++) {
152 struct dst_entry *dst1 = dst_alloc(&xfrm6_dst_ops);
153 struct xfrm_dst *xdst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
155 if (unlikely(dst1 == NULL)) {
156 err = -ENOBUFS;
157 dst_release(&rt->u.dst);
158 goto error;
159 }
160
161 if (!dst)
162 dst = dst1;
163 else {
164 dst_prev->child = dst1;
165 dst1->flags |= DST_NOHASH;
166 dst_clone(dst1);
167 }
168
169 xdst = (struct xfrm_dst *)dst1;
170 xdst->route = &rt->u.dst;
David S. Miller9d4a7062006-08-24 03:18:09 -0700171 xdst->genid = xfrm[i]->genid;
Hideaki YOSHIFUJI92d63dec2005-05-26 12:58:04 -0700172 if (rt->rt6i_node)
173 xdst->route_cookie = rt->rt6i_node->fn_sernum;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174
175 dst1->next = dst_prev;
176 dst_prev = dst1;
Miika Komuc82f9632007-02-06 14:27:02 -0800177
Masahide NAKAMURA1b5c2292006-08-23 18:11:50 -0700178 __xfrm6_bundle_len_inc(&header_len, &nfheader_len, xfrm[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 trailer_len += xfrm[i]->props.trailer_len;
180
Herbert Xu1bfcb102007-10-17 21:31:50 -0700181 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
Miika Komuc82f9632007-02-06 14:27:02 -0800182 unsigned short encap_family = xfrm[i]->props.family;
183 switch(encap_family) {
184 case AF_INET:
185 fl_tunnel.fl4_dst = xfrm[i]->id.daddr.a4;
186 fl_tunnel.fl4_src = xfrm[i]->props.saddr.a4;
187 break;
188 case AF_INET6:
Masahide NAKAMURAbda390d2007-02-09 21:22:16 -0800189 ipv6_addr_copy(&fl_tunnel.fl6_dst, __xfrm6_bundle_addr_remote(xfrm[i], &fl->fl6_dst));
190
Noriaki TAKAMIYAd3f23df2007-02-20 01:08:41 -0800191 ipv6_addr_copy(&fl_tunnel.fl6_src, __xfrm6_bundle_addr_local(xfrm[i], &fl->fl6_src));
Miika Komuc82f9632007-02-06 14:27:02 -0800192 break;
193 default:
194 BUG_ON(1);
195 }
196
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 err = xfrm_dst_lookup((struct xfrm_dst **) &rt,
Miika Komuc82f9632007-02-06 14:27:02 -0800198 &fl_tunnel, encap_family);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 if (err)
200 goto error;
201 } else
202 dst_hold(&rt->u.dst);
203 }
204
205 dst_prev->child = &rt->u.dst;
206 dst->path = &rt->u.dst;
Hideaki YOSHIFUJI92d63dec2005-05-26 12:58:04 -0700207 if (rt->rt6i_node)
208 ((struct xfrm_dst *)dst)->path_cookie = rt->rt6i_node->fn_sernum;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
210 *dst_p = dst;
211 dst = dst_prev;
212
213 dst_prev = *dst_p;
214 i = 0;
215 for (; dst_prev != &rt->u.dst; dst_prev = dst_prev->child) {
216 struct xfrm_dst *x = (struct xfrm_dst*)dst_prev;
217
218 dst_prev->xfrm = xfrm[i++];
219 dst_prev->dev = rt->u.dst.dev;
220 if (rt->u.dst.dev)
221 dev_hold(rt->u.dst.dev);
222 dst_prev->obsolete = -1;
223 dst_prev->flags |= DST_HOST;
224 dst_prev->lastuse = jiffies;
225 dst_prev->header_len = header_len;
Masahide NAKAMURA1b5c2292006-08-23 18:11:50 -0700226 dst_prev->nfheader_len = nfheader_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 dst_prev->trailer_len = trailer_len;
228 memcpy(&dst_prev->metrics, &x->route->metrics, sizeof(dst_prev->metrics));
229
230 /* Copy neighbour for reachability confirmation */
231 dst_prev->neighbour = neigh_clone(rt->u.dst.neighbour);
232 dst_prev->input = rt->u.dst.input;
Herbert Xu13996372007-10-17 21:35:51 -0700233 dst_prev->output = dst_prev->xfrm->outer_mode->afinfo->output;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 /* Sheit... I remember I did this right. Apparently,
235 * it was magically lost, so this code needs audit */
236 x->u.rt6.rt6i_flags = rt0->rt6i_flags&(RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL);
237 x->u.rt6.rt6i_metric = rt0->rt6i_metric;
238 x->u.rt6.rt6i_node = rt0->rt6i_node;
239 x->u.rt6.rt6i_gateway = rt0->rt6i_gateway;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900240 memcpy(&x->u.rt6.rt6i_gateway, &rt0->rt6i_gateway, sizeof(x->u.rt6.rt6i_gateway));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 x->u.rt6.rt6i_dst = rt0->rt6i_dst;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900242 x->u.rt6.rt6i_src = rt0->rt6i_src;
Herbert Xuaabc9762005-05-03 16:27:10 -0700243 x->u.rt6.rt6i_idev = rt0->rt6i_idev;
244 in6_dev_hold(rt0->rt6i_idev);
Masahide NAKAMURA1b5c2292006-08-23 18:11:50 -0700245 __xfrm6_bundle_len_dec(&header_len, &nfheader_len, x->u.dst.xfrm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 trailer_len -= x->u.dst.xfrm->props.trailer_len;
247 }
248
249 xfrm_init_pmtu(dst);
250 return 0;
251
252error:
253 if (dst)
254 dst_free(dst);
255 return err;
256}
257
258static inline void
259_decode_session6(struct sk_buff *skb, struct flowi *fl)
260{
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300261 u16 offset = skb_network_header_len(skb);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700262 struct ipv6hdr *hdr = ipv6_hdr(skb);
YOSHIFUJI Hideakie3cae902006-04-18 14:46:52 -0700263 struct ipv6_opt_hdr *exthdr;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700264 const unsigned char *nh = skb_network_header(skb);
265 u8 nexthdr = nh[IP6CB(skb)->nhoff];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
267 memset(fl, 0, sizeof(struct flowi));
268 ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
269 ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);
270
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700271 while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
272 nh = skb_network_header(skb);
273 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
YOSHIFUJI Hideakie3cae902006-04-18 14:46:52 -0700274
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 switch (nexthdr) {
276 case NEXTHDR_ROUTING:
277 case NEXTHDR_HOP:
278 case NEXTHDR_DEST:
279 offset += ipv6_optlen(exthdr);
280 nexthdr = exthdr->nexthdr;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700281 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 break;
283
284 case IPPROTO_UDP:
Gerrit Renkerba4e58e2006-11-27 11:10:57 -0800285 case IPPROTO_UDPLITE:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 case IPPROTO_TCP:
287 case IPPROTO_SCTP:
Patrick McHardy9e999992005-12-19 14:03:46 -0800288 case IPPROTO_DCCP:
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700289 if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
Al Viro8c689a62006-11-08 00:20:21 -0800290 __be16 *ports = (__be16 *)exthdr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291
292 fl->fl_ip_sport = ports[0];
293 fl->fl_ip_dport = ports[1];
294 }
295 fl->proto = nexthdr;
296 return;
297
298 case IPPROTO_ICMPV6:
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700299 if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 u8 *icmp = (u8 *)exthdr;
301
302 fl->fl_icmp_type = icmp[0];
303 fl->fl_icmp_code = icmp[1];
304 }
305 fl->proto = nexthdr;
306 return;
307
Masahide NAKAMURA59fbb3a62007-06-26 23:56:32 -0700308#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
Masahide NAKAMURA2ce42722006-08-23 20:39:03 -0700309 case IPPROTO_MH:
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700310 if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
Masahide NAKAMURA2ce42722006-08-23 20:39:03 -0700311 struct ip6_mh *mh;
312 mh = (struct ip6_mh *)exthdr;
313
314 fl->fl_mh_type = mh->ip6mh_type;
315 }
316 fl->proto = nexthdr;
317 return;
318#endif
319
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 /* XXX Why are there these headers? */
321 case IPPROTO_AH:
322 case IPPROTO_ESP:
323 case IPPROTO_COMP:
324 default:
325 fl->fl_ipsec_spi = 0;
326 fl->proto = nexthdr;
327 return;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700328 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 }
330}
331
332static inline int xfrm6_garbage_collect(void)
333{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 xfrm6_policy_afinfo.garbage_collect();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_ops.gc_thresh*2);
336}
337
338static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
339{
340 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
341 struct dst_entry *path = xdst->route;
342
343 path->ops->update_pmtu(path, mtu);
344}
345
Herbert Xuaabc9762005-05-03 16:27:10 -0700346static void xfrm6_dst_destroy(struct dst_entry *dst)
347{
348 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
349
350 if (likely(xdst->u.rt6.rt6i_idev))
351 in6_dev_put(xdst->u.rt6.rt6i_idev);
352 xfrm_dst_destroy(xdst);
353}
354
355static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
356 int unregister)
357{
358 struct xfrm_dst *xdst;
359
360 if (!unregister)
361 return;
362
363 xdst = (struct xfrm_dst *)dst;
364 if (xdst->u.rt6.rt6i_idev->dev == dev) {
Eric W. Biederman2774c7a2007-09-26 22:10:56 -0700365 struct inet6_dev *loopback_idev = in6_dev_get(init_net.loopback_dev);
Herbert Xuaabc9762005-05-03 16:27:10 -0700366 BUG_ON(!loopback_idev);
367
368 do {
369 in6_dev_put(xdst->u.rt6.rt6i_idev);
370 xdst->u.rt6.rt6i_idev = loopback_idev;
371 in6_dev_hold(loopback_idev);
372 xdst = (struct xfrm_dst *)xdst->u.dst.child;
373 } while (xdst->u.dst.xfrm);
374
375 __in6_dev_put(loopback_idev);
376 }
377
378 xfrm_dst_ifdown(dst, dev);
379}
380
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381static struct dst_ops xfrm6_dst_ops = {
382 .family = AF_INET6,
383 .protocol = __constant_htons(ETH_P_IPV6),
384 .gc = xfrm6_garbage_collect,
385 .update_pmtu = xfrm6_update_pmtu,
Herbert Xuaabc9762005-05-03 16:27:10 -0700386 .destroy = xfrm6_dst_destroy,
387 .ifdown = xfrm6_dst_ifdown,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 .gc_thresh = 1024,
389 .entry_size = sizeof(struct xfrm_dst),
390};
391
392static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
393 .family = AF_INET6,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 .dst_ops = &xfrm6_dst_ops,
395 .dst_lookup = xfrm6_dst_lookup,
Patrick McHardya1e59ab2006-09-19 12:57:34 -0700396 .get_saddr = xfrm6_get_saddr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 .find_bundle = __xfrm6_find_bundle,
398 .bundle_create = __xfrm6_bundle_create,
399 .decode_session = _decode_session6,
400};
401
402static void __init xfrm6_policy_init(void)
403{
404 xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
405}
406
407static void xfrm6_policy_fini(void)
408{
409 xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
410}
411
412void __init xfrm6_init(void)
413{
414 xfrm6_policy_init();
415 xfrm6_state_init();
416}
417
418void xfrm6_fini(void)
419{
420 //xfrm6_input_fini();
421 xfrm6_policy_fini();
422 xfrm6_state_fini();
423}