Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * xfrm_policy.c | |
3 | * | |
4 | * Changes: | |
5 | * Mitsuru KANDA @USAGI | |
6 | * Kazunori MIYAZAWA @USAGI | |
7 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> | |
8 | * IPv6 support | |
9 | * Kazunori MIYAZAWA @USAGI | |
10 | * YOSHIFUJI Hideaki | |
11 | * Split up af-specific portion | |
12 | * Derek Atkins <derek@ihtfp.com> Add the post_input processor | |
df71837d | 13 | * |
1da177e4 LT |
14 | */ |
15 | ||
1da177e4 LT |
16 | #include <linux/slab.h> |
17 | #include <linux/kmod.h> | |
18 | #include <linux/list.h> | |
19 | #include <linux/spinlock.h> | |
20 | #include <linux/workqueue.h> | |
21 | #include <linux/notifier.h> | |
22 | #include <linux/netdevice.h> | |
eb9c7ebe | 23 | #include <linux/netfilter.h> |
1da177e4 LT |
24 | #include <linux/module.h> |
25 | #include <net/xfrm.h> | |
26 | #include <net/ip.h> | |
27 | ||
4a3e2f71 AV |
28 | DEFINE_MUTEX(xfrm_cfg_mutex); |
29 | EXPORT_SYMBOL(xfrm_cfg_mutex); | |
1da177e4 LT |
30 | |
31 | static DEFINE_RWLOCK(xfrm_policy_lock); | |
32 | ||
33 | struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2]; | |
34 | EXPORT_SYMBOL(xfrm_policy_list); | |
35 | ||
36 | static DEFINE_RWLOCK(xfrm_policy_afinfo_lock); | |
37 | static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO]; | |
38 | ||
ba89966c | 39 | static kmem_cache_t *xfrm_dst_cache __read_mostly; |
1da177e4 LT |
40 | |
41 | static struct work_struct xfrm_policy_gc_work; | |
42 | static struct list_head xfrm_policy_gc_list = | |
43 | LIST_HEAD_INIT(xfrm_policy_gc_list); | |
44 | static DEFINE_SPINLOCK(xfrm_policy_gc_lock); | |
45 | ||
46 | static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family); | |
47 | static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo); | |
546be240 HX |
48 | static struct xfrm_policy_afinfo *xfrm_policy_lock_afinfo(unsigned int family); |
49 | static void xfrm_policy_unlock_afinfo(struct xfrm_policy_afinfo *afinfo); | |
1da177e4 LT |
50 | |
51 | int xfrm_register_type(struct xfrm_type *type, unsigned short family) | |
52 | { | |
546be240 HX |
53 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_lock_afinfo(family); |
54 | struct xfrm_type **typemap; | |
1da177e4 LT |
55 | int err = 0; |
56 | ||
57 | if (unlikely(afinfo == NULL)) | |
58 | return -EAFNOSUPPORT; | |
59 | typemap = afinfo->type_map; | |
60 | ||
546be240 HX |
61 | if (likely(typemap[type->proto] == NULL)) |
62 | typemap[type->proto] = type; | |
1da177e4 LT |
63 | else |
64 | err = -EEXIST; | |
546be240 | 65 | xfrm_policy_unlock_afinfo(afinfo); |
1da177e4 LT |
66 | return err; |
67 | } | |
68 | EXPORT_SYMBOL(xfrm_register_type); | |
69 | ||
70 | int xfrm_unregister_type(struct xfrm_type *type, unsigned short family) | |
71 | { | |
546be240 HX |
72 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_lock_afinfo(family); |
73 | struct xfrm_type **typemap; | |
1da177e4 LT |
74 | int err = 0; |
75 | ||
76 | if (unlikely(afinfo == NULL)) | |
77 | return -EAFNOSUPPORT; | |
78 | typemap = afinfo->type_map; | |
79 | ||
546be240 | 80 | if (unlikely(typemap[type->proto] != type)) |
1da177e4 LT |
81 | err = -ENOENT; |
82 | else | |
546be240 HX |
83 | typemap[type->proto] = NULL; |
84 | xfrm_policy_unlock_afinfo(afinfo); | |
1da177e4 LT |
85 | return err; |
86 | } | |
87 | EXPORT_SYMBOL(xfrm_unregister_type); | |
88 | ||
89 | struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family) | |
90 | { | |
91 | struct xfrm_policy_afinfo *afinfo; | |
546be240 | 92 | struct xfrm_type **typemap; |
1da177e4 LT |
93 | struct xfrm_type *type; |
94 | int modload_attempted = 0; | |
95 | ||
96 | retry: | |
97 | afinfo = xfrm_policy_get_afinfo(family); | |
98 | if (unlikely(afinfo == NULL)) | |
99 | return NULL; | |
100 | typemap = afinfo->type_map; | |
101 | ||
546be240 | 102 | type = typemap[proto]; |
1da177e4 LT |
103 | if (unlikely(type && !try_module_get(type->owner))) |
104 | type = NULL; | |
1da177e4 LT |
105 | if (!type && !modload_attempted) { |
106 | xfrm_policy_put_afinfo(afinfo); | |
107 | request_module("xfrm-type-%d-%d", | |
108 | (int) family, (int) proto); | |
109 | modload_attempted = 1; | |
110 | goto retry; | |
111 | } | |
112 | ||
113 | xfrm_policy_put_afinfo(afinfo); | |
114 | return type; | |
115 | } | |
1da177e4 LT |
116 | |
117 | int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, | |
118 | unsigned short family) | |
119 | { | |
120 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); | |
121 | int err = 0; | |
122 | ||
123 | if (unlikely(afinfo == NULL)) | |
124 | return -EAFNOSUPPORT; | |
125 | ||
126 | if (likely(afinfo->dst_lookup != NULL)) | |
127 | err = afinfo->dst_lookup(dst, fl); | |
128 | else | |
129 | err = -EINVAL; | |
130 | xfrm_policy_put_afinfo(afinfo); | |
131 | return err; | |
132 | } | |
133 | EXPORT_SYMBOL(xfrm_dst_lookup); | |
134 | ||
135 | void xfrm_put_type(struct xfrm_type *type) | |
136 | { | |
137 | module_put(type->owner); | |
138 | } | |
139 | ||
b59f45d0 HX |
140 | int xfrm_register_mode(struct xfrm_mode *mode, int family) |
141 | { | |
142 | struct xfrm_policy_afinfo *afinfo; | |
143 | struct xfrm_mode **modemap; | |
144 | int err; | |
145 | ||
146 | if (unlikely(mode->encap >= XFRM_MODE_MAX)) | |
147 | return -EINVAL; | |
148 | ||
149 | afinfo = xfrm_policy_lock_afinfo(family); | |
150 | if (unlikely(afinfo == NULL)) | |
151 | return -EAFNOSUPPORT; | |
152 | ||
153 | err = -EEXIST; | |
154 | modemap = afinfo->mode_map; | |
155 | if (likely(modemap[mode->encap] == NULL)) { | |
156 | modemap[mode->encap] = mode; | |
157 | err = 0; | |
158 | } | |
159 | ||
160 | xfrm_policy_unlock_afinfo(afinfo); | |
161 | return err; | |
162 | } | |
163 | EXPORT_SYMBOL(xfrm_register_mode); | |
164 | ||
165 | int xfrm_unregister_mode(struct xfrm_mode *mode, int family) | |
166 | { | |
167 | struct xfrm_policy_afinfo *afinfo; | |
168 | struct xfrm_mode **modemap; | |
169 | int err; | |
170 | ||
171 | if (unlikely(mode->encap >= XFRM_MODE_MAX)) | |
172 | return -EINVAL; | |
173 | ||
174 | afinfo = xfrm_policy_lock_afinfo(family); | |
175 | if (unlikely(afinfo == NULL)) | |
176 | return -EAFNOSUPPORT; | |
177 | ||
178 | err = -ENOENT; | |
179 | modemap = afinfo->mode_map; | |
180 | if (likely(modemap[mode->encap] == mode)) { | |
181 | modemap[mode->encap] = NULL; | |
182 | err = 0; | |
183 | } | |
184 | ||
185 | xfrm_policy_unlock_afinfo(afinfo); | |
186 | return err; | |
187 | } | |
188 | EXPORT_SYMBOL(xfrm_unregister_mode); | |
189 | ||
190 | struct xfrm_mode *xfrm_get_mode(unsigned int encap, int family) | |
191 | { | |
192 | struct xfrm_policy_afinfo *afinfo; | |
193 | struct xfrm_mode *mode; | |
194 | int modload_attempted = 0; | |
195 | ||
196 | if (unlikely(encap >= XFRM_MODE_MAX)) | |
197 | return NULL; | |
198 | ||
199 | retry: | |
200 | afinfo = xfrm_policy_get_afinfo(family); | |
201 | if (unlikely(afinfo == NULL)) | |
202 | return NULL; | |
203 | ||
204 | mode = afinfo->mode_map[encap]; | |
205 | if (unlikely(mode && !try_module_get(mode->owner))) | |
206 | mode = NULL; | |
207 | if (!mode && !modload_attempted) { | |
208 | xfrm_policy_put_afinfo(afinfo); | |
209 | request_module("xfrm-mode-%d-%d", family, encap); | |
210 | modload_attempted = 1; | |
211 | goto retry; | |
212 | } | |
213 | ||
214 | xfrm_policy_put_afinfo(afinfo); | |
215 | return mode; | |
216 | } | |
217 | ||
218 | void xfrm_put_mode(struct xfrm_mode *mode) | |
219 | { | |
220 | module_put(mode->owner); | |
221 | } | |
222 | ||
1da177e4 LT |
223 | static inline unsigned long make_jiffies(long secs) |
224 | { | |
225 | if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) | |
226 | return MAX_SCHEDULE_TIMEOUT-1; | |
227 | else | |
228 | return secs*HZ; | |
229 | } | |
230 | ||
231 | static void xfrm_policy_timer(unsigned long data) | |
232 | { | |
233 | struct xfrm_policy *xp = (struct xfrm_policy*)data; | |
234 | unsigned long now = (unsigned long)xtime.tv_sec; | |
235 | long next = LONG_MAX; | |
236 | int warn = 0; | |
237 | int dir; | |
238 | ||
239 | read_lock(&xp->lock); | |
240 | ||
241 | if (xp->dead) | |
242 | goto out; | |
243 | ||
77d8d7a6 | 244 | dir = xfrm_policy_id2dir(xp->index); |
1da177e4 LT |
245 | |
246 | if (xp->lft.hard_add_expires_seconds) { | |
247 | long tmo = xp->lft.hard_add_expires_seconds + | |
248 | xp->curlft.add_time - now; | |
249 | if (tmo <= 0) | |
250 | goto expired; | |
251 | if (tmo < next) | |
252 | next = tmo; | |
253 | } | |
254 | if (xp->lft.hard_use_expires_seconds) { | |
255 | long tmo = xp->lft.hard_use_expires_seconds + | |
256 | (xp->curlft.use_time ? : xp->curlft.add_time) - now; | |
257 | if (tmo <= 0) | |
258 | goto expired; | |
259 | if (tmo < next) | |
260 | next = tmo; | |
261 | } | |
262 | if (xp->lft.soft_add_expires_seconds) { | |
263 | long tmo = xp->lft.soft_add_expires_seconds + | |
264 | xp->curlft.add_time - now; | |
265 | if (tmo <= 0) { | |
266 | warn = 1; | |
267 | tmo = XFRM_KM_TIMEOUT; | |
268 | } | |
269 | if (tmo < next) | |
270 | next = tmo; | |
271 | } | |
272 | if (xp->lft.soft_use_expires_seconds) { | |
273 | long tmo = xp->lft.soft_use_expires_seconds + | |
274 | (xp->curlft.use_time ? : xp->curlft.add_time) - now; | |
275 | if (tmo <= 0) { | |
276 | warn = 1; | |
277 | tmo = XFRM_KM_TIMEOUT; | |
278 | } | |
279 | if (tmo < next) | |
280 | next = tmo; | |
281 | } | |
282 | ||
283 | if (warn) | |
6c5c8ca7 | 284 | km_policy_expired(xp, dir, 0, 0); |
1da177e4 LT |
285 | if (next != LONG_MAX && |
286 | !mod_timer(&xp->timer, jiffies + make_jiffies(next))) | |
287 | xfrm_pol_hold(xp); | |
288 | ||
289 | out: | |
290 | read_unlock(&xp->lock); | |
291 | xfrm_pol_put(xp); | |
292 | return; | |
293 | ||
294 | expired: | |
295 | read_unlock(&xp->lock); | |
4666faab | 296 | if (!xfrm_policy_delete(xp, dir)) |
6c5c8ca7 | 297 | km_policy_expired(xp, dir, 1, 0); |
1da177e4 LT |
298 | xfrm_pol_put(xp); |
299 | } | |
300 | ||
301 | ||
302 | /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 | |
303 | * SPD calls. | |
304 | */ | |
305 | ||
dd0fc66f | 306 | struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp) |
1da177e4 LT |
307 | { |
308 | struct xfrm_policy *policy; | |
309 | ||
0da974f4 | 310 | policy = kzalloc(sizeof(struct xfrm_policy), gfp); |
1da177e4 LT |
311 | |
312 | if (policy) { | |
1da177e4 LT |
313 | atomic_set(&policy->refcnt, 1); |
314 | rwlock_init(&policy->lock); | |
315 | init_timer(&policy->timer); | |
316 | policy->timer.data = (unsigned long)policy; | |
317 | policy->timer.function = xfrm_policy_timer; | |
318 | } | |
319 | return policy; | |
320 | } | |
321 | EXPORT_SYMBOL(xfrm_policy_alloc); | |
322 | ||
323 | /* Destroy xfrm_policy: descendant resources must be released to this moment. */ | |
324 | ||
325 | void __xfrm_policy_destroy(struct xfrm_policy *policy) | |
326 | { | |
09a62660 | 327 | BUG_ON(!policy->dead); |
1da177e4 | 328 | |
09a62660 | 329 | BUG_ON(policy->bundles); |
1da177e4 LT |
330 | |
331 | if (del_timer(&policy->timer)) | |
332 | BUG(); | |
333 | ||
df71837d | 334 | security_xfrm_policy_free(policy); |
1da177e4 LT |
335 | kfree(policy); |
336 | } | |
337 | EXPORT_SYMBOL(__xfrm_policy_destroy); | |
338 | ||
339 | static void xfrm_policy_gc_kill(struct xfrm_policy *policy) | |
340 | { | |
341 | struct dst_entry *dst; | |
342 | ||
343 | while ((dst = policy->bundles) != NULL) { | |
344 | policy->bundles = dst->next; | |
345 | dst_free(dst); | |
346 | } | |
347 | ||
348 | if (del_timer(&policy->timer)) | |
349 | atomic_dec(&policy->refcnt); | |
350 | ||
351 | if (atomic_read(&policy->refcnt) > 1) | |
352 | flow_cache_flush(); | |
353 | ||
354 | xfrm_pol_put(policy); | |
355 | } | |
356 | ||
357 | static void xfrm_policy_gc_task(void *data) | |
358 | { | |
359 | struct xfrm_policy *policy; | |
360 | struct list_head *entry, *tmp; | |
361 | struct list_head gc_list = LIST_HEAD_INIT(gc_list); | |
362 | ||
363 | spin_lock_bh(&xfrm_policy_gc_lock); | |
364 | list_splice_init(&xfrm_policy_gc_list, &gc_list); | |
365 | spin_unlock_bh(&xfrm_policy_gc_lock); | |
366 | ||
367 | list_for_each_safe(entry, tmp, &gc_list) { | |
368 | policy = list_entry(entry, struct xfrm_policy, list); | |
369 | xfrm_policy_gc_kill(policy); | |
370 | } | |
371 | } | |
372 | ||
373 | /* Rule must be locked. Release descentant resources, announce | |
374 | * entry dead. The rule must be unlinked from lists to the moment. | |
375 | */ | |
376 | ||
377 | static void xfrm_policy_kill(struct xfrm_policy *policy) | |
378 | { | |
379 | int dead; | |
380 | ||
381 | write_lock_bh(&policy->lock); | |
382 | dead = policy->dead; | |
383 | policy->dead = 1; | |
384 | write_unlock_bh(&policy->lock); | |
385 | ||
386 | if (unlikely(dead)) { | |
387 | WARN_ON(1); | |
388 | return; | |
389 | } | |
390 | ||
391 | spin_lock(&xfrm_policy_gc_lock); | |
392 | list_add(&policy->list, &xfrm_policy_gc_list); | |
393 | spin_unlock(&xfrm_policy_gc_lock); | |
394 | ||
395 | schedule_work(&xfrm_policy_gc_work); | |
396 | } | |
397 | ||
398 | /* Generate new index... KAME seems to generate them ordered by cost | |
399 | * of an absolute inpredictability of ordering of rules. This will not pass. */ | |
400 | static u32 xfrm_gen_index(int dir) | |
401 | { | |
402 | u32 idx; | |
403 | struct xfrm_policy *p; | |
404 | static u32 idx_generator; | |
405 | ||
406 | for (;;) { | |
407 | idx = (idx_generator | dir); | |
408 | idx_generator += 8; | |
409 | if (idx == 0) | |
410 | idx = 8; | |
411 | for (p = xfrm_policy_list[dir]; p; p = p->next) { | |
412 | if (p->index == idx) | |
413 | break; | |
414 | } | |
415 | if (!p) | |
416 | return idx; | |
417 | } | |
418 | } | |
419 | ||
420 | int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) | |
421 | { | |
422 | struct xfrm_policy *pol, **p; | |
423 | struct xfrm_policy *delpol = NULL; | |
424 | struct xfrm_policy **newpos = NULL; | |
9b78a82c | 425 | struct dst_entry *gc_list; |
1da177e4 LT |
426 | |
427 | write_lock_bh(&xfrm_policy_lock); | |
428 | for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL;) { | |
df71837d TJ |
429 | if (!delpol && memcmp(&policy->selector, &pol->selector, sizeof(pol->selector)) == 0 && |
430 | xfrm_sec_ctx_match(pol->security, policy->security)) { | |
1da177e4 LT |
431 | if (excl) { |
432 | write_unlock_bh(&xfrm_policy_lock); | |
433 | return -EEXIST; | |
434 | } | |
435 | *p = pol->next; | |
436 | delpol = pol; | |
437 | if (policy->priority > pol->priority) | |
438 | continue; | |
439 | } else if (policy->priority >= pol->priority) { | |
440 | p = &pol->next; | |
441 | continue; | |
442 | } | |
443 | if (!newpos) | |
444 | newpos = p; | |
445 | if (delpol) | |
446 | break; | |
447 | p = &pol->next; | |
448 | } | |
449 | if (newpos) | |
450 | p = newpos; | |
451 | xfrm_pol_hold(policy); | |
452 | policy->next = *p; | |
453 | *p = policy; | |
454 | atomic_inc(&flow_cache_genid); | |
455 | policy->index = delpol ? delpol->index : xfrm_gen_index(dir); | |
456 | policy->curlft.add_time = (unsigned long)xtime.tv_sec; | |
457 | policy->curlft.use_time = 0; | |
458 | if (!mod_timer(&policy->timer, jiffies + HZ)) | |
459 | xfrm_pol_hold(policy); | |
460 | write_unlock_bh(&xfrm_policy_lock); | |
461 | ||
9b78a82c | 462 | if (delpol) |
1da177e4 | 463 | xfrm_policy_kill(delpol); |
9b78a82c DM |
464 | |
465 | read_lock_bh(&xfrm_policy_lock); | |
466 | gc_list = NULL; | |
467 | for (policy = policy->next; policy; policy = policy->next) { | |
468 | struct dst_entry *dst; | |
469 | ||
470 | write_lock(&policy->lock); | |
471 | dst = policy->bundles; | |
472 | if (dst) { | |
473 | struct dst_entry *tail = dst; | |
474 | while (tail->next) | |
475 | tail = tail->next; | |
476 | tail->next = gc_list; | |
477 | gc_list = dst; | |
478 | ||
479 | policy->bundles = NULL; | |
480 | } | |
481 | write_unlock(&policy->lock); | |
1da177e4 | 482 | } |
9b78a82c DM |
483 | read_unlock_bh(&xfrm_policy_lock); |
484 | ||
485 | while (gc_list) { | |
486 | struct dst_entry *dst = gc_list; | |
487 | ||
488 | gc_list = dst->next; | |
489 | dst_free(dst); | |
490 | } | |
491 | ||
1da177e4 LT |
492 | return 0; |
493 | } | |
494 | EXPORT_SYMBOL(xfrm_policy_insert); | |
495 | ||
df71837d TJ |
496 | struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel, |
497 | struct xfrm_sec_ctx *ctx, int delete) | |
1da177e4 LT |
498 | { |
499 | struct xfrm_policy *pol, **p; | |
500 | ||
501 | write_lock_bh(&xfrm_policy_lock); | |
502 | for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) { | |
df71837d TJ |
503 | if ((memcmp(sel, &pol->selector, sizeof(*sel)) == 0) && |
504 | (xfrm_sec_ctx_match(ctx, pol->security))) { | |
1da177e4 LT |
505 | xfrm_pol_hold(pol); |
506 | if (delete) | |
507 | *p = pol->next; | |
508 | break; | |
509 | } | |
510 | } | |
511 | write_unlock_bh(&xfrm_policy_lock); | |
512 | ||
513 | if (pol && delete) { | |
514 | atomic_inc(&flow_cache_genid); | |
515 | xfrm_policy_kill(pol); | |
516 | } | |
517 | return pol; | |
518 | } | |
df71837d | 519 | EXPORT_SYMBOL(xfrm_policy_bysel_ctx); |
1da177e4 LT |
520 | |
521 | struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete) | |
522 | { | |
523 | struct xfrm_policy *pol, **p; | |
524 | ||
525 | write_lock_bh(&xfrm_policy_lock); | |
77d8d7a6 | 526 | for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) { |
1da177e4 LT |
527 | if (pol->index == id) { |
528 | xfrm_pol_hold(pol); | |
529 | if (delete) | |
530 | *p = pol->next; | |
531 | break; | |
532 | } | |
533 | } | |
534 | write_unlock_bh(&xfrm_policy_lock); | |
535 | ||
536 | if (pol && delete) { | |
537 | atomic_inc(&flow_cache_genid); | |
538 | xfrm_policy_kill(pol); | |
539 | } | |
540 | return pol; | |
541 | } | |
542 | EXPORT_SYMBOL(xfrm_policy_byid); | |
543 | ||
544 | void xfrm_policy_flush(void) | |
545 | { | |
546 | struct xfrm_policy *xp; | |
547 | int dir; | |
548 | ||
549 | write_lock_bh(&xfrm_policy_lock); | |
550 | for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { | |
551 | while ((xp = xfrm_policy_list[dir]) != NULL) { | |
552 | xfrm_policy_list[dir] = xp->next; | |
553 | write_unlock_bh(&xfrm_policy_lock); | |
554 | ||
555 | xfrm_policy_kill(xp); | |
556 | ||
557 | write_lock_bh(&xfrm_policy_lock); | |
558 | } | |
559 | } | |
560 | atomic_inc(&flow_cache_genid); | |
561 | write_unlock_bh(&xfrm_policy_lock); | |
562 | } | |
563 | EXPORT_SYMBOL(xfrm_policy_flush); | |
564 | ||
565 | int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), | |
566 | void *data) | |
567 | { | |
568 | struct xfrm_policy *xp; | |
569 | int dir; | |
570 | int count = 0; | |
571 | int error = 0; | |
572 | ||
573 | read_lock_bh(&xfrm_policy_lock); | |
574 | for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) { | |
575 | for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) | |
576 | count++; | |
577 | } | |
578 | ||
579 | if (count == 0) { | |
580 | error = -ENOENT; | |
581 | goto out; | |
582 | } | |
583 | ||
584 | for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) { | |
585 | for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) { | |
586 | error = func(xp, dir%XFRM_POLICY_MAX, --count, data); | |
587 | if (error) | |
588 | goto out; | |
589 | } | |
590 | } | |
591 | ||
592 | out: | |
593 | read_unlock_bh(&xfrm_policy_lock); | |
594 | return error; | |
595 | } | |
596 | EXPORT_SYMBOL(xfrm_policy_walk); | |
597 | ||
598 | /* Find policy to apply to this flow. */ | |
599 | ||
df71837d | 600 | static void xfrm_policy_lookup(struct flowi *fl, u32 sk_sid, u16 family, u8 dir, |
1da177e4 LT |
601 | void **objp, atomic_t **obj_refp) |
602 | { | |
603 | struct xfrm_policy *pol; | |
604 | ||
605 | read_lock_bh(&xfrm_policy_lock); | |
606 | for (pol = xfrm_policy_list[dir]; pol; pol = pol->next) { | |
607 | struct xfrm_selector *sel = &pol->selector; | |
608 | int match; | |
609 | ||
610 | if (pol->family != family) | |
611 | continue; | |
612 | ||
613 | match = xfrm_selector_match(sel, fl, family); | |
df71837d | 614 | |
1da177e4 | 615 | if (match) { |
df71837d TJ |
616 | if (!security_xfrm_policy_lookup(pol, sk_sid, dir)) { |
617 | xfrm_pol_hold(pol); | |
618 | break; | |
619 | } | |
1da177e4 LT |
620 | } |
621 | } | |
622 | read_unlock_bh(&xfrm_policy_lock); | |
623 | if ((*objp = (void *) pol) != NULL) | |
624 | *obj_refp = &pol->refcnt; | |
625 | } | |
626 | ||
df71837d TJ |
627 | static inline int policy_to_flow_dir(int dir) |
628 | { | |
629 | if (XFRM_POLICY_IN == FLOW_DIR_IN && | |
630 | XFRM_POLICY_OUT == FLOW_DIR_OUT && | |
631 | XFRM_POLICY_FWD == FLOW_DIR_FWD) | |
632 | return dir; | |
633 | switch (dir) { | |
634 | default: | |
635 | case XFRM_POLICY_IN: | |
636 | return FLOW_DIR_IN; | |
637 | case XFRM_POLICY_OUT: | |
638 | return FLOW_DIR_OUT; | |
639 | case XFRM_POLICY_FWD: | |
640 | return FLOW_DIR_FWD; | |
641 | }; | |
642 | } | |
643 | ||
644 | static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl, u32 sk_sid) | |
1da177e4 LT |
645 | { |
646 | struct xfrm_policy *pol; | |
647 | ||
648 | read_lock_bh(&xfrm_policy_lock); | |
649 | if ((pol = sk->sk_policy[dir]) != NULL) { | |
df71837d | 650 | int match = xfrm_selector_match(&pol->selector, fl, |
1da177e4 | 651 | sk->sk_family); |
df71837d TJ |
652 | int err = 0; |
653 | ||
1da177e4 | 654 | if (match) |
df71837d TJ |
655 | err = security_xfrm_policy_lookup(pol, sk_sid, policy_to_flow_dir(dir)); |
656 | ||
657 | if (match && !err) | |
1da177e4 LT |
658 | xfrm_pol_hold(pol); |
659 | else | |
660 | pol = NULL; | |
661 | } | |
662 | read_unlock_bh(&xfrm_policy_lock); | |
663 | return pol; | |
664 | } | |
665 | ||
666 | static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) | |
667 | { | |
668 | pol->next = xfrm_policy_list[dir]; | |
669 | xfrm_policy_list[dir] = pol; | |
670 | xfrm_pol_hold(pol); | |
671 | } | |
672 | ||
673 | static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, | |
674 | int dir) | |
675 | { | |
676 | struct xfrm_policy **polp; | |
677 | ||
678 | for (polp = &xfrm_policy_list[dir]; | |
679 | *polp != NULL; polp = &(*polp)->next) { | |
680 | if (*polp == pol) { | |
681 | *polp = pol->next; | |
682 | return pol; | |
683 | } | |
684 | } | |
685 | return NULL; | |
686 | } | |
687 | ||
4666faab | 688 | int xfrm_policy_delete(struct xfrm_policy *pol, int dir) |
1da177e4 LT |
689 | { |
690 | write_lock_bh(&xfrm_policy_lock); | |
691 | pol = __xfrm_policy_unlink(pol, dir); | |
692 | write_unlock_bh(&xfrm_policy_lock); | |
693 | if (pol) { | |
694 | if (dir < XFRM_POLICY_MAX) | |
695 | atomic_inc(&flow_cache_genid); | |
696 | xfrm_policy_kill(pol); | |
4666faab | 697 | return 0; |
1da177e4 | 698 | } |
4666faab | 699 | return -ENOENT; |
1da177e4 | 700 | } |
a70fcb0b | 701 | EXPORT_SYMBOL(xfrm_policy_delete); |
1da177e4 LT |
702 | |
703 | int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) | |
704 | { | |
705 | struct xfrm_policy *old_pol; | |
706 | ||
707 | write_lock_bh(&xfrm_policy_lock); | |
708 | old_pol = sk->sk_policy[dir]; | |
709 | sk->sk_policy[dir] = pol; | |
710 | if (pol) { | |
711 | pol->curlft.add_time = (unsigned long)xtime.tv_sec; | |
712 | pol->index = xfrm_gen_index(XFRM_POLICY_MAX+dir); | |
713 | __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir); | |
714 | } | |
715 | if (old_pol) | |
716 | __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir); | |
717 | write_unlock_bh(&xfrm_policy_lock); | |
718 | ||
719 | if (old_pol) { | |
720 | xfrm_policy_kill(old_pol); | |
721 | } | |
722 | return 0; | |
723 | } | |
724 | ||
725 | static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir) | |
726 | { | |
727 | struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC); | |
728 | ||
729 | if (newp) { | |
730 | newp->selector = old->selector; | |
df71837d TJ |
731 | if (security_xfrm_policy_clone(old, newp)) { |
732 | kfree(newp); | |
733 | return NULL; /* ENOMEM */ | |
734 | } | |
1da177e4 LT |
735 | newp->lft = old->lft; |
736 | newp->curlft = old->curlft; | |
737 | newp->action = old->action; | |
738 | newp->flags = old->flags; | |
739 | newp->xfrm_nr = old->xfrm_nr; | |
740 | newp->index = old->index; | |
741 | memcpy(newp->xfrm_vec, old->xfrm_vec, | |
742 | newp->xfrm_nr*sizeof(struct xfrm_tmpl)); | |
743 | write_lock_bh(&xfrm_policy_lock); | |
744 | __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir); | |
745 | write_unlock_bh(&xfrm_policy_lock); | |
746 | xfrm_pol_put(newp); | |
747 | } | |
748 | return newp; | |
749 | } | |
750 | ||
751 | int __xfrm_sk_clone_policy(struct sock *sk) | |
752 | { | |
753 | struct xfrm_policy *p0 = sk->sk_policy[0], | |
754 | *p1 = sk->sk_policy[1]; | |
755 | ||
756 | sk->sk_policy[0] = sk->sk_policy[1] = NULL; | |
757 | if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL) | |
758 | return -ENOMEM; | |
759 | if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL) | |
760 | return -ENOMEM; | |
761 | return 0; | |
762 | } | |
763 | ||
764 | /* Resolve list of templates for the flow, given policy. */ | |
765 | ||
766 | static int | |
767 | xfrm_tmpl_resolve(struct xfrm_policy *policy, struct flowi *fl, | |
768 | struct xfrm_state **xfrm, | |
769 | unsigned short family) | |
770 | { | |
771 | int nx; | |
772 | int i, error; | |
773 | xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); | |
774 | xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); | |
775 | ||
776 | for (nx=0, i = 0; i < policy->xfrm_nr; i++) { | |
777 | struct xfrm_state *x; | |
778 | xfrm_address_t *remote = daddr; | |
779 | xfrm_address_t *local = saddr; | |
780 | struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; | |
781 | ||
782 | if (tmpl->mode) { | |
783 | remote = &tmpl->id.daddr; | |
784 | local = &tmpl->saddr; | |
785 | } | |
786 | ||
787 | x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); | |
788 | ||
789 | if (x && x->km.state == XFRM_STATE_VALID) { | |
790 | xfrm[nx++] = x; | |
791 | daddr = remote; | |
792 | saddr = local; | |
793 | continue; | |
794 | } | |
795 | if (x) { | |
796 | error = (x->km.state == XFRM_STATE_ERROR ? | |
797 | -EINVAL : -EAGAIN); | |
798 | xfrm_state_put(x); | |
799 | } | |
800 | ||
801 | if (!tmpl->optional) | |
802 | goto fail; | |
803 | } | |
804 | return nx; | |
805 | ||
806 | fail: | |
807 | for (nx--; nx>=0; nx--) | |
808 | xfrm_state_put(xfrm[nx]); | |
809 | return error; | |
810 | } | |
811 | ||
812 | /* Check that the bundle accepts the flow and its components are | |
813 | * still valid. | |
814 | */ | |
815 | ||
816 | static struct dst_entry * | |
817 | xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family) | |
818 | { | |
819 | struct dst_entry *x; | |
820 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); | |
821 | if (unlikely(afinfo == NULL)) | |
822 | return ERR_PTR(-EINVAL); | |
823 | x = afinfo->find_bundle(fl, policy); | |
824 | xfrm_policy_put_afinfo(afinfo); | |
825 | return x; | |
826 | } | |
827 | ||
828 | /* Allocate chain of dst_entry's, attach known xfrm's, calculate | |
829 | * all the metrics... Shortly, bundle a bundle. | |
830 | */ | |
831 | ||
832 | static int | |
833 | xfrm_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx, | |
834 | struct flowi *fl, struct dst_entry **dst_p, | |
835 | unsigned short family) | |
836 | { | |
837 | int err; | |
838 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); | |
839 | if (unlikely(afinfo == NULL)) | |
840 | return -EINVAL; | |
841 | err = afinfo->bundle_create(policy, xfrm, nx, fl, dst_p); | |
842 | xfrm_policy_put_afinfo(afinfo); | |
843 | return err; | |
844 | } | |
845 | ||
1da177e4 LT |
846 | |
847 | static int stale_bundle(struct dst_entry *dst); | |
848 | ||
849 | /* Main function: finds/creates a bundle for given flow. | |
850 | * | |
851 | * At the moment we eat a raw IP route. Mostly to speed up lookups | |
852 | * on interfaces with disabled IPsec. | |
853 | */ | |
854 | int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl, | |
855 | struct sock *sk, int flags) | |
856 | { | |
857 | struct xfrm_policy *policy; | |
858 | struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; | |
859 | struct dst_entry *dst, *dst_orig = *dst_p; | |
860 | int nx = 0; | |
861 | int err; | |
862 | u32 genid; | |
42cf93cd | 863 | u16 family; |
df71837d TJ |
864 | u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT); |
865 | u32 sk_sid = security_sk_sid(sk, fl, dir); | |
1da177e4 LT |
866 | restart: |
867 | genid = atomic_read(&flow_cache_genid); | |
868 | policy = NULL; | |
869 | if (sk && sk->sk_policy[1]) | |
df71837d | 870 | policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, sk_sid); |
1da177e4 LT |
871 | |
872 | if (!policy) { | |
873 | /* To accelerate a bit... */ | |
874 | if ((dst_orig->flags & DST_NOXFRM) || !xfrm_policy_list[XFRM_POLICY_OUT]) | |
875 | return 0; | |
876 | ||
42cf93cd PM |
877 | policy = flow_cache_lookup(fl, sk_sid, dst_orig->ops->family, |
878 | dir, xfrm_policy_lookup); | |
1da177e4 LT |
879 | } |
880 | ||
881 | if (!policy) | |
882 | return 0; | |
883 | ||
42cf93cd | 884 | family = dst_orig->ops->family; |
1da177e4 LT |
885 | policy->curlft.use_time = (unsigned long)xtime.tv_sec; |
886 | ||
887 | switch (policy->action) { | |
888 | case XFRM_POLICY_BLOCK: | |
889 | /* Prohibit the flow */ | |
e104411b PM |
890 | err = -EPERM; |
891 | goto error; | |
1da177e4 LT |
892 | |
893 | case XFRM_POLICY_ALLOW: | |
894 | if (policy->xfrm_nr == 0) { | |
895 | /* Flow passes not transformed. */ | |
896 | xfrm_pol_put(policy); | |
897 | return 0; | |
898 | } | |
899 | ||
900 | /* Try to find matching bundle. | |
901 | * | |
902 | * LATER: help from flow cache. It is optional, this | |
903 | * is required only for output policy. | |
904 | */ | |
905 | dst = xfrm_find_bundle(fl, policy, family); | |
906 | if (IS_ERR(dst)) { | |
e104411b PM |
907 | err = PTR_ERR(dst); |
908 | goto error; | |
1da177e4 LT |
909 | } |
910 | ||
911 | if (dst) | |
912 | break; | |
913 | ||
914 | nx = xfrm_tmpl_resolve(policy, fl, xfrm, family); | |
915 | ||
916 | if (unlikely(nx<0)) { | |
917 | err = nx; | |
918 | if (err == -EAGAIN && flags) { | |
919 | DECLARE_WAITQUEUE(wait, current); | |
920 | ||
921 | add_wait_queue(&km_waitq, &wait); | |
922 | set_current_state(TASK_INTERRUPTIBLE); | |
923 | schedule(); | |
924 | set_current_state(TASK_RUNNING); | |
925 | remove_wait_queue(&km_waitq, &wait); | |
926 | ||
927 | nx = xfrm_tmpl_resolve(policy, fl, xfrm, family); | |
928 | ||
929 | if (nx == -EAGAIN && signal_pending(current)) { | |
930 | err = -ERESTART; | |
931 | goto error; | |
932 | } | |
933 | if (nx == -EAGAIN || | |
934 | genid != atomic_read(&flow_cache_genid)) { | |
935 | xfrm_pol_put(policy); | |
936 | goto restart; | |
937 | } | |
938 | err = nx; | |
939 | } | |
940 | if (err < 0) | |
941 | goto error; | |
942 | } | |
943 | if (nx == 0) { | |
944 | /* Flow passes not transformed. */ | |
945 | xfrm_pol_put(policy); | |
946 | return 0; | |
947 | } | |
948 | ||
949 | dst = dst_orig; | |
950 | err = xfrm_bundle_create(policy, xfrm, nx, fl, &dst, family); | |
951 | ||
952 | if (unlikely(err)) { | |
953 | int i; | |
954 | for (i=0; i<nx; i++) | |
955 | xfrm_state_put(xfrm[i]); | |
956 | goto error; | |
957 | } | |
958 | ||
959 | write_lock_bh(&policy->lock); | |
960 | if (unlikely(policy->dead || stale_bundle(dst))) { | |
961 | /* Wow! While we worked on resolving, this | |
962 | * policy has gone. Retry. It is not paranoia, | |
963 | * we just cannot enlist new bundle to dead object. | |
964 | * We can't enlist stable bundles either. | |
965 | */ | |
966 | write_unlock_bh(&policy->lock); | |
1da177e4 LT |
967 | if (dst) |
968 | dst_free(dst); | |
00de651d HX |
969 | |
970 | err = -EHOSTUNREACH; | |
971 | goto error; | |
1da177e4 LT |
972 | } |
973 | dst->next = policy->bundles; | |
974 | policy->bundles = dst; | |
975 | dst_hold(dst); | |
976 | write_unlock_bh(&policy->lock); | |
977 | } | |
978 | *dst_p = dst; | |
979 | dst_release(dst_orig); | |
980 | xfrm_pol_put(policy); | |
981 | return 0; | |
982 | ||
983 | error: | |
984 | dst_release(dst_orig); | |
985 | xfrm_pol_put(policy); | |
986 | *dst_p = NULL; | |
987 | return err; | |
988 | } | |
989 | EXPORT_SYMBOL(xfrm_lookup); | |
990 | ||
991 | /* When skb is transformed back to its "native" form, we have to | |
992 | * check policy restrictions. At the moment we make this in maximally | |
993 | * stupid way. Shame on me. :-) Of course, connected sockets must | |
994 | * have policy cached at them. | |
995 | */ | |
996 | ||
997 | static inline int | |
998 | xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x, | |
999 | unsigned short family) | |
1000 | { | |
1001 | if (xfrm_state_kern(x)) | |
1002 | return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, family); | |
1003 | return x->id.proto == tmpl->id.proto && | |
1004 | (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && | |
1005 | (x->props.reqid == tmpl->reqid || !tmpl->reqid) && | |
1006 | x->props.mode == tmpl->mode && | |
1007 | (tmpl->aalgos & (1<<x->props.aalgo)) && | |
1008 | !(x->props.mode && xfrm_state_addr_cmp(tmpl, x, family)); | |
1009 | } | |
1010 | ||
1011 | static inline int | |
1012 | xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start, | |
1013 | unsigned short family) | |
1014 | { | |
1015 | int idx = start; | |
1016 | ||
1017 | if (tmpl->optional) { | |
1018 | if (!tmpl->mode) | |
1019 | return start; | |
1020 | } else | |
1021 | start = -1; | |
1022 | for (; idx < sp->len; idx++) { | |
dbe5b4aa | 1023 | if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) |
1da177e4 | 1024 | return ++idx; |
dbe5b4aa | 1025 | if (sp->xvec[idx]->props.mode) |
1da177e4 LT |
1026 | break; |
1027 | } | |
1028 | return start; | |
1029 | } | |
1030 | ||
3e3850e9 PM |
1031 | int |
1032 | xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family) | |
1da177e4 LT |
1033 | { |
1034 | struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); | |
1035 | ||
1036 | if (unlikely(afinfo == NULL)) | |
1037 | return -EAFNOSUPPORT; | |
1038 | ||
1039 | afinfo->decode_session(skb, fl); | |
1040 | xfrm_policy_put_afinfo(afinfo); | |
1041 | return 0; | |
1042 | } | |
3e3850e9 | 1043 | EXPORT_SYMBOL(xfrm_decode_session); |
1da177e4 LT |
1044 | |
1045 | static inline int secpath_has_tunnel(struct sec_path *sp, int k) | |
1046 | { | |
1047 | for (; k < sp->len; k++) { | |
dbe5b4aa | 1048 | if (sp->xvec[k]->props.mode) |
1da177e4 LT |
1049 | return 1; |
1050 | } | |
1051 | ||
1052 | return 0; | |
1053 | } | |
1054 | ||
1055 | int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, | |
1056 | unsigned short family) | |
1057 | { | |
1058 | struct xfrm_policy *pol; | |
1059 | struct flowi fl; | |
df71837d TJ |
1060 | u8 fl_dir = policy_to_flow_dir(dir); |
1061 | u32 sk_sid; | |
1da177e4 | 1062 | |
3e3850e9 | 1063 | if (xfrm_decode_session(skb, &fl, family) < 0) |
1da177e4 | 1064 | return 0; |
eb9c7ebe | 1065 | nf_nat_decode_session(skb, &fl, family); |
1da177e4 | 1066 | |
df71837d TJ |
1067 | sk_sid = security_sk_sid(sk, &fl, fl_dir); |
1068 | ||
1da177e4 LT |
1069 | /* First, check used SA against their selectors. */ |
1070 | if (skb->sp) { | |
1071 | int i; | |
1072 | ||
1073 | for (i=skb->sp->len-1; i>=0; i--) { | |
dbe5b4aa HX |
1074 | struct xfrm_state *x = skb->sp->xvec[i]; |
1075 | if (!xfrm_selector_match(&x->sel, &fl, family)) | |
1da177e4 | 1076 | return 0; |
1da177e4 LT |
1077 | } |
1078 | } | |
1079 | ||
1080 | pol = NULL; | |
1081 | if (sk && sk->sk_policy[dir]) | |
df71837d | 1082 | pol = xfrm_sk_policy_lookup(sk, dir, &fl, sk_sid); |
1da177e4 LT |
1083 | |
1084 | if (!pol) | |
df71837d | 1085 | pol = flow_cache_lookup(&fl, sk_sid, family, fl_dir, |
1da177e4 LT |
1086 | xfrm_policy_lookup); |
1087 | ||
1088 | if (!pol) | |
1089 | return !skb->sp || !secpath_has_tunnel(skb->sp, 0); | |
1090 | ||
1091 | pol->curlft.use_time = (unsigned long)xtime.tv_sec; | |
1092 | ||
1093 | if (pol->action == XFRM_POLICY_ALLOW) { | |
1094 | struct sec_path *sp; | |
1095 | static struct sec_path dummy; | |
1096 | int i, k; | |
1097 | ||
1098 | if ((sp = skb->sp) == NULL) | |
1099 | sp = &dummy; | |
1100 | ||
1101 | /* For each tunnel xfrm, find the first matching tmpl. | |
1102 | * For each tmpl before that, find corresponding xfrm. | |
1103 | * Order is _important_. Later we will implement | |
1104 | * some barriers, but at the moment barriers | |
1105 | * are implied between each two transformations. | |
1106 | */ | |
1107 | for (i = pol->xfrm_nr-1, k = 0; i >= 0; i--) { | |
1108 | k = xfrm_policy_ok(pol->xfrm_vec+i, sp, k, family); | |
1109 | if (k < 0) | |
1110 | goto reject; | |
1111 | } | |
1112 | ||
1113 | if (secpath_has_tunnel(sp, k)) | |
1114 | goto reject; | |
1115 | ||
1116 | xfrm_pol_put(pol); | |
1117 | return 1; | |
1118 | } | |
1119 | ||
1120 | reject: | |
1121 | xfrm_pol_put(pol); | |
1122 | return 0; | |
1123 | } | |
1124 | EXPORT_SYMBOL(__xfrm_policy_check); | |
1125 | ||
1126 | int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) | |
1127 | { | |
1128 | struct flowi fl; | |
1129 | ||
3e3850e9 | 1130 | if (xfrm_decode_session(skb, &fl, family) < 0) |
1da177e4 LT |
1131 | return 0; |
1132 | ||
1133 | return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0; | |
1134 | } | |
1135 | EXPORT_SYMBOL(__xfrm_route_forward); | |
1136 | ||
d49c73c7 DM |
1137 | /* Optimize later using cookies and generation ids. */ |
1138 | ||
1da177e4 LT |
1139 | static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) |
1140 | { | |
d49c73c7 DM |
1141 | /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete |
1142 | * to "-1" to force all XFRM destinations to get validated by | |
1143 | * dst_ops->check on every use. We do this because when a | |
1144 | * normal route referenced by an XFRM dst is obsoleted we do | |
1145 | * not go looking around for all parent referencing XFRM dsts | |
1146 | * so that we can invalidate them. It is just too much work. | |
1147 | * Instead we make the checks here on every use. For example: | |
1148 | * | |
1149 | * XFRM dst A --> IPv4 dst X | |
1150 | * | |
1151 | * X is the "xdst->route" of A (X is also the "dst->path" of A | |
1152 | * in this example). If X is marked obsolete, "A" will not | |
1153 | * notice. That's what we are validating here via the | |
1154 | * stale_bundle() check. | |
1155 | * | |
1156 | * When a policy's bundle is pruned, we dst_free() the XFRM | |
1157 | * dst which causes it's ->obsolete field to be set to a | |
1158 | * positive non-zero integer. If an XFRM dst has been pruned | |
1159 | * like this, we want to force a new route lookup. | |
399c180a | 1160 | */ |
d49c73c7 DM |
1161 | if (dst->obsolete < 0 && !stale_bundle(dst)) |
1162 | return dst; | |
1163 | ||
1da177e4 LT |
1164 | return NULL; |
1165 | } | |
1166 | ||
1167 | static int stale_bundle(struct dst_entry *dst) | |
1168 | { | |
1169 | return !xfrm_bundle_ok((struct xfrm_dst *)dst, NULL, AF_UNSPEC); | |
1170 | } | |
1171 | ||
aabc9761 | 1172 | void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) |
1da177e4 | 1173 | { |
1da177e4 LT |
1174 | while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { |
1175 | dst->dev = &loopback_dev; | |
1176 | dev_hold(&loopback_dev); | |
1177 | dev_put(dev); | |
1178 | } | |
1179 | } | |
aabc9761 | 1180 | EXPORT_SYMBOL(xfrm_dst_ifdown); |
1da177e4 LT |
1181 | |
1182 | static void xfrm_link_failure(struct sk_buff *skb) | |
1183 | { | |
1184 | /* Impossible. Such dst must be popped before reaches point of failure. */ | |
1185 | return; | |
1186 | } | |
1187 | ||
1188 | static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) | |
1189 | { | |
1190 | if (dst) { | |
1191 | if (dst->obsolete) { | |
1192 | dst_release(dst); | |
1193 | dst = NULL; | |
1194 | } | |
1195 | } | |
1196 | return dst; | |
1197 | } | |
1198 | ||
1199 | static void xfrm_prune_bundles(int (*func)(struct dst_entry *)) | |
1200 | { | |
1201 | int i; | |
1202 | struct xfrm_policy *pol; | |
1203 | struct dst_entry *dst, **dstp, *gc_list = NULL; | |
1204 | ||
1205 | read_lock_bh(&xfrm_policy_lock); | |
1206 | for (i=0; i<2*XFRM_POLICY_MAX; i++) { | |
1207 | for (pol = xfrm_policy_list[i]; pol; pol = pol->next) { | |
1208 | write_lock(&pol->lock); | |
1209 | dstp = &pol->bundles; | |
1210 | while ((dst=*dstp) != NULL) { | |
1211 | if (func(dst)) { | |
1212 | *dstp = dst->next; | |
1213 | dst->next = gc_list; | |
1214 | gc_list = dst; | |
1215 | } else { | |
1216 | dstp = &dst->next; | |
1217 | } | |
1218 | } | |
1219 | write_unlock(&pol->lock); | |
1220 | } | |
1221 | } | |
1222 | read_unlock_bh(&xfrm_policy_lock); | |
1223 | ||
1224 | while (gc_list) { | |
1225 | dst = gc_list; | |
1226 | gc_list = dst->next; | |
1227 | dst_free(dst); | |
1228 | } | |
1229 | } | |
1230 | ||
1231 | static int unused_bundle(struct dst_entry *dst) | |
1232 | { | |
1233 | return !atomic_read(&dst->__refcnt); | |
1234 | } | |
1235 | ||
1236 | static void __xfrm_garbage_collect(void) | |
1237 | { | |
1238 | xfrm_prune_bundles(unused_bundle); | |
1239 | } | |
1240 | ||
1241 | int xfrm_flush_bundles(void) | |
1242 | { | |
1243 | xfrm_prune_bundles(stale_bundle); | |
1244 | return 0; | |
1245 | } | |
1246 | ||
399c180a DM |
1247 | static int always_true(struct dst_entry *dst) |
1248 | { | |
1249 | return 1; | |
1250 | } | |
1251 | ||
1252 | void xfrm_flush_all_bundles(void) | |
1253 | { | |
1254 | xfrm_prune_bundles(always_true); | |
1255 | } | |
1256 | ||
1da177e4 LT |
1257 | void xfrm_init_pmtu(struct dst_entry *dst) |
1258 | { | |
1259 | do { | |
1260 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; | |
1261 | u32 pmtu, route_mtu_cached; | |
1262 | ||
1263 | pmtu = dst_mtu(dst->child); | |
1264 | xdst->child_mtu_cached = pmtu; | |
1265 | ||
1266 | pmtu = xfrm_state_mtu(dst->xfrm, pmtu); | |
1267 | ||
1268 | route_mtu_cached = dst_mtu(xdst->route); | |
1269 | xdst->route_mtu_cached = route_mtu_cached; | |
1270 | ||
1271 | if (pmtu > route_mtu_cached) | |
1272 | pmtu = route_mtu_cached; | |
1273 | ||
1274 | dst->metrics[RTAX_MTU-1] = pmtu; | |
1275 | } while ((dst = dst->next)); | |
1276 | } | |
1277 | ||
1278 | EXPORT_SYMBOL(xfrm_init_pmtu); | |
1279 | ||
1280 | /* Check that the bundle accepts the flow and its components are | |
1281 | * still valid. | |
1282 | */ | |
1283 | ||
1284 | int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family) | |
1285 | { | |
1286 | struct dst_entry *dst = &first->u.dst; | |
1287 | struct xfrm_dst *last; | |
1288 | u32 mtu; | |
1289 | ||
92d63dec | 1290 | if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) || |
1da177e4 LT |
1291 | (dst->dev && !netif_running(dst->dev))) |
1292 | return 0; | |
1293 | ||
1294 | last = NULL; | |
1295 | ||
1296 | do { | |
1297 | struct xfrm_dst *xdst = (struct xfrm_dst *)dst; | |
1298 | ||
1299 | if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family)) | |
1300 | return 0; | |
1301 | if (dst->xfrm->km.state != XFRM_STATE_VALID) | |
1302 | return 0; | |
1303 | ||
1304 | mtu = dst_mtu(dst->child); | |
1305 | if (xdst->child_mtu_cached != mtu) { | |
1306 | last = xdst; | |
1307 | xdst->child_mtu_cached = mtu; | |
1308 | } | |
1309 | ||
92d63dec | 1310 | if (!dst_check(xdst->route, xdst->route_cookie)) |
1da177e4 LT |
1311 | return 0; |
1312 | mtu = dst_mtu(xdst->route); | |
1313 | if (xdst->route_mtu_cached != mtu) { | |
1314 | last = xdst; | |
1315 | xdst->route_mtu_cached = mtu; | |
1316 | } | |
1317 | ||
1318 | dst = dst->child; | |
1319 | } while (dst->xfrm); | |
1320 | ||
1321 | if (likely(!last)) | |
1322 | return 1; | |
1323 | ||
1324 | mtu = last->child_mtu_cached; | |
1325 | for (;;) { | |
1326 | dst = &last->u.dst; | |
1327 | ||
1328 | mtu = xfrm_state_mtu(dst->xfrm, mtu); | |
1329 | if (mtu > last->route_mtu_cached) | |
1330 | mtu = last->route_mtu_cached; | |
1331 | dst->metrics[RTAX_MTU-1] = mtu; | |
1332 | ||
1333 | if (last == first) | |
1334 | break; | |
1335 | ||
1336 | last = last->u.next; | |
1337 | last->child_mtu_cached = mtu; | |
1338 | } | |
1339 | ||
1340 | return 1; | |
1341 | } | |
1342 | ||
1343 | EXPORT_SYMBOL(xfrm_bundle_ok); | |
1344 | ||
1da177e4 LT |
1345 | int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo) |
1346 | { | |
1347 | int err = 0; | |
1348 | if (unlikely(afinfo == NULL)) | |
1349 | return -EINVAL; | |
1350 | if (unlikely(afinfo->family >= NPROTO)) | |
1351 | return -EAFNOSUPPORT; | |
e959d812 | 1352 | write_lock_bh(&xfrm_policy_afinfo_lock); |
1da177e4 LT |
1353 | if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL)) |
1354 | err = -ENOBUFS; | |
1355 | else { | |
1356 | struct dst_ops *dst_ops = afinfo->dst_ops; | |
1357 | if (likely(dst_ops->kmem_cachep == NULL)) | |
1358 | dst_ops->kmem_cachep = xfrm_dst_cache; | |
1359 | if (likely(dst_ops->check == NULL)) | |
1360 | dst_ops->check = xfrm_dst_check; | |
1da177e4 LT |
1361 | if (likely(dst_ops->negative_advice == NULL)) |
1362 | dst_ops->negative_advice = xfrm_negative_advice; | |
1363 | if (likely(dst_ops->link_failure == NULL)) | |
1364 | dst_ops->link_failure = xfrm_link_failure; | |
1da177e4 LT |
1365 | if (likely(afinfo->garbage_collect == NULL)) |
1366 | afinfo->garbage_collect = __xfrm_garbage_collect; | |
1367 | xfrm_policy_afinfo[afinfo->family] = afinfo; | |
1368 | } | |
e959d812 | 1369 | write_unlock_bh(&xfrm_policy_afinfo_lock); |
1da177e4 LT |
1370 | return err; |
1371 | } | |
1372 | EXPORT_SYMBOL(xfrm_policy_register_afinfo); | |
1373 | ||
1374 | int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo) | |
1375 | { | |
1376 | int err = 0; | |
1377 | if (unlikely(afinfo == NULL)) | |
1378 | return -EINVAL; | |
1379 | if (unlikely(afinfo->family >= NPROTO)) | |
1380 | return -EAFNOSUPPORT; | |
e959d812 | 1381 | write_lock_bh(&xfrm_policy_afinfo_lock); |
1da177e4 LT |
1382 | if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) { |
1383 | if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo)) | |
1384 | err = -EINVAL; | |
1385 | else { | |
1386 | struct dst_ops *dst_ops = afinfo->dst_ops; | |
1387 | xfrm_policy_afinfo[afinfo->family] = NULL; | |
1388 | dst_ops->kmem_cachep = NULL; | |
1389 | dst_ops->check = NULL; | |
1da177e4 LT |
1390 | dst_ops->negative_advice = NULL; |
1391 | dst_ops->link_failure = NULL; | |
1da177e4 LT |
1392 | afinfo->garbage_collect = NULL; |
1393 | } | |
1394 | } | |
e959d812 | 1395 | write_unlock_bh(&xfrm_policy_afinfo_lock); |
1da177e4 LT |
1396 | return err; |
1397 | } | |
1398 | EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); | |
1399 | ||
1400 | static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) | |
1401 | { | |
1402 | struct xfrm_policy_afinfo *afinfo; | |
1403 | if (unlikely(family >= NPROTO)) | |
1404 | return NULL; | |
1405 | read_lock(&xfrm_policy_afinfo_lock); | |
1406 | afinfo = xfrm_policy_afinfo[family]; | |
546be240 HX |
1407 | if (unlikely(!afinfo)) |
1408 | read_unlock(&xfrm_policy_afinfo_lock); | |
1da177e4 LT |
1409 | return afinfo; |
1410 | } | |
1411 | ||
1412 | static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo) | |
1413 | { | |
546be240 HX |
1414 | read_unlock(&xfrm_policy_afinfo_lock); |
1415 | } | |
1416 | ||
1417 | static struct xfrm_policy_afinfo *xfrm_policy_lock_afinfo(unsigned int family) | |
1418 | { | |
1419 | struct xfrm_policy_afinfo *afinfo; | |
1420 | if (unlikely(family >= NPROTO)) | |
1421 | return NULL; | |
1422 | write_lock_bh(&xfrm_policy_afinfo_lock); | |
1423 | afinfo = xfrm_policy_afinfo[family]; | |
1424 | if (unlikely(!afinfo)) | |
1425 | write_unlock_bh(&xfrm_policy_afinfo_lock); | |
1426 | return afinfo; | |
1427 | } | |
1428 | ||
1429 | static void xfrm_policy_unlock_afinfo(struct xfrm_policy_afinfo *afinfo) | |
1430 | { | |
1431 | write_unlock_bh(&xfrm_policy_afinfo_lock); | |
1da177e4 LT |
1432 | } |
1433 | ||
1434 | static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr) | |
1435 | { | |
1436 | switch (event) { | |
1437 | case NETDEV_DOWN: | |
1438 | xfrm_flush_bundles(); | |
1439 | } | |
1440 | return NOTIFY_DONE; | |
1441 | } | |
1442 | ||
1443 | static struct notifier_block xfrm_dev_notifier = { | |
1444 | xfrm_dev_event, | |
1445 | NULL, | |
1446 | 0 | |
1447 | }; | |
1448 | ||
1449 | static void __init xfrm_policy_init(void) | |
1450 | { | |
1451 | xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", | |
1452 | sizeof(struct xfrm_dst), | |
1453 | 0, SLAB_HWCACHE_ALIGN, | |
1454 | NULL, NULL); | |
1455 | if (!xfrm_dst_cache) | |
1456 | panic("XFRM: failed to allocate xfrm_dst_cache\n"); | |
1457 | ||
1458 | INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task, NULL); | |
1459 | register_netdevice_notifier(&xfrm_dev_notifier); | |
1460 | } | |
1461 | ||
1462 | void __init xfrm_init(void) | |
1463 | { | |
1464 | xfrm_state_init(); | |
1465 | xfrm_policy_init(); | |
1466 | xfrm_input_init(); | |
1467 | } | |
1468 |