?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
ext2: disallow setting xip on remount
[linux-2.6/zen-sources.git] / net / ipv6 / xfrm6_policy.c
blob1faa2ea80afc19e2ef246768388604ef616dde40
1 /*
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
11 *
12 */
13
14 #include <linux/compiler.h>
15 #include <linux/netdevice.h>
16 #include <net/addrconf.h>
17 #include <net/xfrm.h>
18 #include <net/ip.h>
19 #include <net/ipv6.h>
20 #include <net/ip6_route.h>
21 #ifdef CONFIG_IPV6_MIP6
22 #include <net/mip6.h>
23 #endif
24
25 static struct dst_ops xfrm6_dst_ops;
26 static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
27
28 static int xfrm6_dst_lookup(struct xfrm_dst **xdst, struct flowi *fl)
29 {
30 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);
36 return err;
37 }
38
39 static 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
59 static 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) &&
78 xfrm_bundle_ok(policy, xdst, fl, AF_INET6,
79 (xdst->u.rt6.rt6i_dst.plen != 128 ||
80 xdst->u.rt6.rt6i_src.plen != 128))) {
81 dst_clone(dst);
82 break;
83 }
84 }
85 read_unlock_bh(&policy->lock);
86 return dst;
87 }
88
89 static 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
97 static 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
105 static 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
114 static 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
123 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
124 * all the metrics... Shortly, bundle a bundle.
125 */
126
127 static 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;
134 struct flowi fl_tunnel = {
135 .nl_u = {
136 .ip6_u = {
137 .saddr = fl->fl6_src,
138 .daddr = fl->fl6_dst,
139 }
140 }
141 };
142 int i;
143 int err = 0;
144 int header_len = 0;
145 int nfheader_len = 0;
146 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;
154
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;
171 xdst->genid = xfrm[i]->genid;
172 if (rt->rt6i_node)
173 xdst->route_cookie = rt->rt6i_node->fn_sernum;
174
175 dst1->next = dst_prev;
176 dst_prev = dst1;
177
178 __xfrm6_bundle_len_inc(&header_len, &nfheader_len, xfrm[i]);
179 trailer_len += xfrm[i]->props.trailer_len;
180
181 if (xfrm[i]->props.mode == XFRM_MODE_TUNNEL ||
182 xfrm[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION) {
183 unsigned short encap_family = xfrm[i]->props.family;
184 switch(encap_family) {
185 case AF_INET:
186 fl_tunnel.fl4_dst = xfrm[i]->id.daddr.a4;
187 fl_tunnel.fl4_src = xfrm[i]->props.saddr.a4;
188 break;
189 case AF_INET6:
190 ipv6_addr_copy(&fl_tunnel.fl6_dst, __xfrm6_bundle_addr_remote(xfrm[i], &fl->fl6_dst));
191
192 ipv6_addr_copy(&fl_tunnel.fl6_src, __xfrm6_bundle_addr_local(xfrm[i], &fl->fl6_src));
193 break;
194 default:
195 BUG_ON(1);
196 }
197
198 err = xfrm_dst_lookup((struct xfrm_dst **) &rt,
199 &fl_tunnel, encap_family);
200 if (err)
201 goto error;
202 } else
203 dst_hold(&rt->u.dst);
204 }
205
206 dst_prev->child = &rt->u.dst;
207 dst->path = &rt->u.dst;
208 if (rt->rt6i_node)
209 ((struct xfrm_dst *)dst)->path_cookie = rt->rt6i_node->fn_sernum;
210
211 *dst_p = dst;
212 dst = dst_prev;
213
214 dst_prev = *dst_p;
215 i = 0;
216 for (; dst_prev != &rt->u.dst; dst_prev = dst_prev->child) {
217 struct xfrm_dst *x = (struct xfrm_dst*)dst_prev;
218 struct xfrm_state_afinfo *afinfo;
219
220 dst_prev->xfrm = xfrm[i++];
221 dst_prev->dev = rt->u.dst.dev;
222 if (rt->u.dst.dev)
223 dev_hold(rt->u.dst.dev);
224 dst_prev->obsolete = -1;
225 dst_prev->flags |= DST_HOST;
226 dst_prev->lastuse = jiffies;
227 dst_prev->header_len = header_len;
228 dst_prev->nfheader_len = nfheader_len;
229 dst_prev->trailer_len = trailer_len;
230 memcpy(&dst_prev->metrics, &x->route->metrics, sizeof(dst_prev->metrics));
231
232 /* Copy neighbour for reachability confirmation */
233 dst_prev->neighbour = neigh_clone(rt->u.dst.neighbour);
234 dst_prev->input = rt->u.dst.input;
235 /* XXX: When IPv4 is implemented as module and can be unloaded,
236 * we should manage reference to xfrm4_output in afinfo->output.
237 * Miyazawa
238 */
239 afinfo = xfrm_state_get_afinfo(dst_prev->xfrm->props.family);
240 if (!afinfo) {
241 dst = *dst_p;
242 goto error;
243 }
244
245 dst_prev->output = afinfo->output;
246 xfrm_state_put_afinfo(afinfo);
247 /* Sheit... I remember I did this right. Apparently,
248 * it was magically lost, so this code needs audit */
249 x->u.rt6.rt6i_flags = rt0->rt6i_flags&(RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL);
250 x->u.rt6.rt6i_metric = rt0->rt6i_metric;
251 x->u.rt6.rt6i_node = rt0->rt6i_node;
252 x->u.rt6.rt6i_gateway = rt0->rt6i_gateway;
253 memcpy(&x->u.rt6.rt6i_gateway, &rt0->rt6i_gateway, sizeof(x->u.rt6.rt6i_gateway));
254 x->u.rt6.rt6i_dst = rt0->rt6i_dst;
255 x->u.rt6.rt6i_src = rt0->rt6i_src;
256 x->u.rt6.rt6i_idev = rt0->rt6i_idev;
257 in6_dev_hold(rt0->rt6i_idev);
258 __xfrm6_bundle_len_dec(&header_len, &nfheader_len, x->u.dst.xfrm);
259 trailer_len -= x->u.dst.xfrm->props.trailer_len;
260 }
261
262 xfrm_init_pmtu(dst);
263 return 0;
264
265 error:
266 if (dst)
267 dst_free(dst);
268 return err;
269 }
270
271 static inline void
272 _decode_session6(struct sk_buff *skb, struct flowi *fl)
273 {
274 u16 offset = skb_network_header_len(skb);
275 struct ipv6hdr *hdr = ipv6_hdr(skb);
276 struct ipv6_opt_hdr *exthdr;
277 const unsigned char *nh = skb_network_header(skb);
278 u8 nexthdr = nh[IP6CB(skb)->nhoff];
279
280 memset(fl, 0, sizeof(struct flowi));
281 ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
282 ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);
283
284 while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
285 nh = skb_network_header(skb);
286 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
287
288 switch (nexthdr) {
289 case NEXTHDR_ROUTING:
290 case NEXTHDR_HOP:
291 case NEXTHDR_DEST:
292 offset += ipv6_optlen(exthdr);
293 nexthdr = exthdr->nexthdr;
294 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
295 break;
296
297 case IPPROTO_UDP:
298 case IPPROTO_UDPLITE:
299 case IPPROTO_TCP:
300 case IPPROTO_SCTP:
301 case IPPROTO_DCCP:
302 if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
303 __be16 *ports = (__be16 *)exthdr;
304
305 fl->fl_ip_sport = ports[0];
306 fl->fl_ip_dport = ports[1];
307 }
308 fl->proto = nexthdr;
309 return;
310
311 case IPPROTO_ICMPV6:
312 if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
313 u8 *icmp = (u8 *)exthdr;
314
315 fl->fl_icmp_type = icmp[0];
316 fl->fl_icmp_code = icmp[1];
317 }
318 fl->proto = nexthdr;
319 return;
320
321 #ifdef CONFIG_IPV6_MIP6
322 case IPPROTO_MH:
323 if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
324 struct ip6_mh *mh;
325 mh = (struct ip6_mh *)exthdr;
326
327 fl->fl_mh_type = mh->ip6mh_type;
328 }
329 fl->proto = nexthdr;
330 return;
331 #endif
332
333 /* XXX Why are there these headers? */
334 case IPPROTO_AH:
335 case IPPROTO_ESP:
336 case IPPROTO_COMP:
337 default:
338 fl->fl_ipsec_spi = 0;
339 fl->proto = nexthdr;
340 return;
341 }
342 }
343 }
344
345 static inline int xfrm6_garbage_collect(void)
346 {
347 xfrm6_policy_afinfo.garbage_collect();
348 return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_ops.gc_thresh*2);
349 }
350
351 static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
352 {
353 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
354 struct dst_entry *path = xdst->route;
355
356 path->ops->update_pmtu(path, mtu);
357 }
358
359 static void xfrm6_dst_destroy(struct dst_entry *dst)
360 {
361 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
362
363 if (likely(xdst->u.rt6.rt6i_idev))
364 in6_dev_put(xdst->u.rt6.rt6i_idev);
365 xfrm_dst_destroy(xdst);
366 }
367
368 static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
369 int unregister)
370 {
371 struct xfrm_dst *xdst;
372
373 if (!unregister)
374 return;
375
376 xdst = (struct xfrm_dst *)dst;
377 if (xdst->u.rt6.rt6i_idev->dev == dev) {
378 struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev);
379 BUG_ON(!loopback_idev);
380
381 do {
382 in6_dev_put(xdst->u.rt6.rt6i_idev);
383 xdst->u.rt6.rt6i_idev = loopback_idev;
384 in6_dev_hold(loopback_idev);
385 xdst = (struct xfrm_dst *)xdst->u.dst.child;
386 } while (xdst->u.dst.xfrm);
387
388 __in6_dev_put(loopback_idev);
389 }
390
391 xfrm_dst_ifdown(dst, dev);
392 }
393
394 static struct dst_ops xfrm6_dst_ops = {
395 .family = AF_INET6,
396 .protocol = __constant_htons(ETH_P_IPV6),
397 .gc = xfrm6_garbage_collect,
398 .update_pmtu = xfrm6_update_pmtu,
399 .destroy = xfrm6_dst_destroy,
400 .ifdown = xfrm6_dst_ifdown,
401 .gc_thresh = 1024,
402 .entry_size = sizeof(struct xfrm_dst),
403 };
404
405 static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
406 .family = AF_INET6,
407 .dst_ops = &xfrm6_dst_ops,
408 .dst_lookup = xfrm6_dst_lookup,
409 .get_saddr = xfrm6_get_saddr,
410 .find_bundle = __xfrm6_find_bundle,
411 .bundle_create = __xfrm6_bundle_create,
412 .decode_session = _decode_session6,
413 };
414
415 static void __init xfrm6_policy_init(void)
416 {
417 xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
418 }
419
420 static void xfrm6_policy_fini(void)
421 {
422 xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
423 }
424
425 void __init xfrm6_init(void)
426 {
427 xfrm6_policy_init();
428 xfrm6_state_init();
429 }
430
431 void xfrm6_fini(void)
432 {
433 //xfrm6_input_fini();
434 xfrm6_policy_fini();
435 xfrm6_state_fini();
436 }
Stable & featurefull patchset based on Linus's git branch