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Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/configh
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / xfrm / xfrm_policy.c
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
13 *
14 */
15
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>
23 #include <linux/netfilter.h>
24 #include <linux/module.h>
25 #include <linux/cache.h>
26 #include <net/xfrm.h>
27 #include <net/ip.h>
28
29 #include "xfrm_hash.h"
30
31 DEFINE_MUTEX(xfrm_cfg_mutex);
32 EXPORT_SYMBOL(xfrm_cfg_mutex);
33
34 static DEFINE_RWLOCK(xfrm_policy_lock);
35
36 unsigned int xfrm_policy_count[XFRM_POLICY_MAX*2];
37 EXPORT_SYMBOL(xfrm_policy_count);
38
39 static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
40 static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
41
42 static kmem_cache_t *xfrm_dst_cache __read_mostly;
43
44 static struct work_struct xfrm_policy_gc_work;
45 static HLIST_HEAD(xfrm_policy_gc_list);
46 static DEFINE_SPINLOCK(xfrm_policy_gc_lock);
47
48 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
49 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
50 static struct xfrm_policy_afinfo *xfrm_policy_lock_afinfo(unsigned int family);
51 static void xfrm_policy_unlock_afinfo(struct xfrm_policy_afinfo *afinfo);
52
53 int xfrm_register_type(struct xfrm_type *type, unsigned short family)
54 {
55 struct xfrm_policy_afinfo *afinfo = xfrm_policy_lock_afinfo(family);
56 struct xfrm_type **typemap;
57 int err = 0;
58
59 if (unlikely(afinfo == NULL))
60 return -EAFNOSUPPORT;
61 typemap = afinfo->type_map;
62
63 if (likely(typemap[type->proto] == NULL))
64 typemap[type->proto] = type;
65 else
66 err = -EEXIST;
67 xfrm_policy_unlock_afinfo(afinfo);
68 return err;
69 }
70 EXPORT_SYMBOL(xfrm_register_type);
71
72 int xfrm_unregister_type(struct xfrm_type *type, unsigned short family)
73 {
74 struct xfrm_policy_afinfo *afinfo = xfrm_policy_lock_afinfo(family);
75 struct xfrm_type **typemap;
76 int err = 0;
77
78 if (unlikely(afinfo == NULL))
79 return -EAFNOSUPPORT;
80 typemap = afinfo->type_map;
81
82 if (unlikely(typemap[type->proto] != type))
83 err = -ENOENT;
84 else
85 typemap[type->proto] = NULL;
86 xfrm_policy_unlock_afinfo(afinfo);
87 return err;
88 }
89 EXPORT_SYMBOL(xfrm_unregister_type);
90
91 struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family)
92 {
93 struct xfrm_policy_afinfo *afinfo;
94 struct xfrm_type **typemap;
95 struct xfrm_type *type;
96 int modload_attempted = 0;
97
98 retry:
99 afinfo = xfrm_policy_get_afinfo(family);
100 if (unlikely(afinfo == NULL))
101 return NULL;
102 typemap = afinfo->type_map;
103
104 type = typemap[proto];
105 if (unlikely(type && !try_module_get(type->owner)))
106 type = NULL;
107 if (!type && !modload_attempted) {
108 xfrm_policy_put_afinfo(afinfo);
109 request_module("xfrm-type-%d-%d",
110 (int) family, (int) proto);
111 modload_attempted = 1;
112 goto retry;
113 }
114
115 xfrm_policy_put_afinfo(afinfo);
116 return type;
117 }
118
119 int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl,
120 unsigned short family)
121 {
122 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
123 int err = 0;
124
125 if (unlikely(afinfo == NULL))
126 return -EAFNOSUPPORT;
127
128 if (likely(afinfo->dst_lookup != NULL))
129 err = afinfo->dst_lookup(dst, fl);
130 else
131 err = -EINVAL;
132 xfrm_policy_put_afinfo(afinfo);
133 return err;
134 }
135 EXPORT_SYMBOL(xfrm_dst_lookup);
136
137 void xfrm_put_type(struct xfrm_type *type)
138 {
139 module_put(type->owner);
140 }
141
142 int xfrm_register_mode(struct xfrm_mode *mode, int family)
143 {
144 struct xfrm_policy_afinfo *afinfo;
145 struct xfrm_mode **modemap;
146 int err;
147
148 if (unlikely(mode->encap >= XFRM_MODE_MAX))
149 return -EINVAL;
150
151 afinfo = xfrm_policy_lock_afinfo(family);
152 if (unlikely(afinfo == NULL))
153 return -EAFNOSUPPORT;
154
155 err = -EEXIST;
156 modemap = afinfo->mode_map;
157 if (likely(modemap[mode->encap] == NULL)) {
158 modemap[mode->encap] = mode;
159 err = 0;
160 }
161
162 xfrm_policy_unlock_afinfo(afinfo);
163 return err;
164 }
165 EXPORT_SYMBOL(xfrm_register_mode);
166
167 int xfrm_unregister_mode(struct xfrm_mode *mode, int family)
168 {
169 struct xfrm_policy_afinfo *afinfo;
170 struct xfrm_mode **modemap;
171 int err;
172
173 if (unlikely(mode->encap >= XFRM_MODE_MAX))
174 return -EINVAL;
175
176 afinfo = xfrm_policy_lock_afinfo(family);
177 if (unlikely(afinfo == NULL))
178 return -EAFNOSUPPORT;
179
180 err = -ENOENT;
181 modemap = afinfo->mode_map;
182 if (likely(modemap[mode->encap] == mode)) {
183 modemap[mode->encap] = NULL;
184 err = 0;
185 }
186
187 xfrm_policy_unlock_afinfo(afinfo);
188 return err;
189 }
190 EXPORT_SYMBOL(xfrm_unregister_mode);
191
192 struct xfrm_mode *xfrm_get_mode(unsigned int encap, int family)
193 {
194 struct xfrm_policy_afinfo *afinfo;
195 struct xfrm_mode *mode;
196 int modload_attempted = 0;
197
198 if (unlikely(encap >= XFRM_MODE_MAX))
199 return NULL;
200
201 retry:
202 afinfo = xfrm_policy_get_afinfo(family);
203 if (unlikely(afinfo == NULL))
204 return NULL;
205
206 mode = afinfo->mode_map[encap];
207 if (unlikely(mode && !try_module_get(mode->owner)))
208 mode = NULL;
209 if (!mode && !modload_attempted) {
210 xfrm_policy_put_afinfo(afinfo);
211 request_module("xfrm-mode-%d-%d", family, encap);
212 modload_attempted = 1;
213 goto retry;
214 }
215
216 xfrm_policy_put_afinfo(afinfo);
217 return mode;
218 }
219
220 void xfrm_put_mode(struct xfrm_mode *mode)
221 {
222 module_put(mode->owner);
223 }
224
225 static inline unsigned long make_jiffies(long secs)
226 {
227 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
228 return MAX_SCHEDULE_TIMEOUT-1;
229 else
230 return secs*HZ;
231 }
232
233 static void xfrm_policy_timer(unsigned long data)
234 {
235 struct xfrm_policy *xp = (struct xfrm_policy*)data;
236 unsigned long now = (unsigned long)xtime.tv_sec;
237 long next = LONG_MAX;
238 int warn = 0;
239 int dir;
240
241 read_lock(&xp->lock);
242
243 if (xp->dead)
244 goto out;
245
246 dir = xfrm_policy_id2dir(xp->index);
247
248 if (xp->lft.hard_add_expires_seconds) {
249 long tmo = xp->lft.hard_add_expires_seconds +
250 xp->curlft.add_time - now;
251 if (tmo <= 0)
252 goto expired;
253 if (tmo < next)
254 next = tmo;
255 }
256 if (xp->lft.hard_use_expires_seconds) {
257 long tmo = xp->lft.hard_use_expires_seconds +
258 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
259 if (tmo <= 0)
260 goto expired;
261 if (tmo < next)
262 next = tmo;
263 }
264 if (xp->lft.soft_add_expires_seconds) {
265 long tmo = xp->lft.soft_add_expires_seconds +
266 xp->curlft.add_time - now;
267 if (tmo <= 0) {
268 warn = 1;
269 tmo = XFRM_KM_TIMEOUT;
270 }
271 if (tmo < next)
272 next = tmo;
273 }
274 if (xp->lft.soft_use_expires_seconds) {
275 long tmo = xp->lft.soft_use_expires_seconds +
276 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
277 if (tmo <= 0) {
278 warn = 1;
279 tmo = XFRM_KM_TIMEOUT;
280 }
281 if (tmo < next)
282 next = tmo;
283 }
284
285 if (warn)
286 km_policy_expired(xp, dir, 0, 0);
287 if (next != LONG_MAX &&
288 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
289 xfrm_pol_hold(xp);
290
291 out:
292 read_unlock(&xp->lock);
293 xfrm_pol_put(xp);
294 return;
295
296 expired:
297 read_unlock(&xp->lock);
298 if (!xfrm_policy_delete(xp, dir))
299 km_policy_expired(xp, dir, 1, 0);
300 xfrm_pol_put(xp);
301 }
302
303
304 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
305 * SPD calls.
306 */
307
308 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp)
309 {
310 struct xfrm_policy *policy;
311
312 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
313
314 if (policy) {
315 INIT_HLIST_NODE(&policy->bydst);
316 INIT_HLIST_NODE(&policy->byidx);
317 rwlock_init(&policy->lock);
318 atomic_set(&policy->refcnt, 1);
319 init_timer(&policy->timer);
320 policy->timer.data = (unsigned long)policy;
321 policy->timer.function = xfrm_policy_timer;
322 }
323 return policy;
324 }
325 EXPORT_SYMBOL(xfrm_policy_alloc);
326
327 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
328
329 void __xfrm_policy_destroy(struct xfrm_policy *policy)
330 {
331 BUG_ON(!policy->dead);
332
333 BUG_ON(policy->bundles);
334
335 if (del_timer(&policy->timer))
336 BUG();
337
338 security_xfrm_policy_free(policy);
339 kfree(policy);
340 }
341 EXPORT_SYMBOL(__xfrm_policy_destroy);
342
343 static void xfrm_policy_gc_kill(struct xfrm_policy *policy)
344 {
345 struct dst_entry *dst;
346
347 while ((dst = policy->bundles) != NULL) {
348 policy->bundles = dst->next;
349 dst_free(dst);
350 }
351
352 if (del_timer(&policy->timer))
353 atomic_dec(&policy->refcnt);
354
355 if (atomic_read(&policy->refcnt) > 1)
356 flow_cache_flush();
357
358 xfrm_pol_put(policy);
359 }
360
361 static void xfrm_policy_gc_task(void *data)
362 {
363 struct xfrm_policy *policy;
364 struct hlist_node *entry, *tmp;
365 struct hlist_head gc_list;
366
367 spin_lock_bh(&xfrm_policy_gc_lock);
368 gc_list.first = xfrm_policy_gc_list.first;
369 INIT_HLIST_HEAD(&xfrm_policy_gc_list);
370 spin_unlock_bh(&xfrm_policy_gc_lock);
371
372 hlist_for_each_entry_safe(policy, entry, tmp, &gc_list, bydst)
373 xfrm_policy_gc_kill(policy);
374 }
375
376 /* Rule must be locked. Release descentant resources, announce
377 * entry dead. The rule must be unlinked from lists to the moment.
378 */
379
380 static void xfrm_policy_kill(struct xfrm_policy *policy)
381 {
382 int dead;
383
384 write_lock_bh(&policy->lock);
385 dead = policy->dead;
386 policy->dead = 1;
387 write_unlock_bh(&policy->lock);
388
389 if (unlikely(dead)) {
390 WARN_ON(1);
391 return;
392 }
393
394 spin_lock(&xfrm_policy_gc_lock);
395 hlist_add_head(&policy->bydst, &xfrm_policy_gc_list);
396 spin_unlock(&xfrm_policy_gc_lock);
397
398 schedule_work(&xfrm_policy_gc_work);
399 }
400
401 struct xfrm_policy_hash {
402 struct hlist_head *table;
403 unsigned int hmask;
404 };
405
406 static struct hlist_head xfrm_policy_inexact[XFRM_POLICY_MAX*2];
407 static struct xfrm_policy_hash xfrm_policy_bydst[XFRM_POLICY_MAX*2] __read_mostly;
408 static struct hlist_head *xfrm_policy_byidx __read_mostly;
409 static unsigned int xfrm_idx_hmask __read_mostly;
410 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
411
412 static inline unsigned int idx_hash(u32 index)
413 {
414 return __idx_hash(index, xfrm_idx_hmask);
415 }
416
417 static struct hlist_head *policy_hash_bysel(struct xfrm_selector *sel, unsigned short family, int dir)
418 {
419 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
420 unsigned int hash = __sel_hash(sel, family, hmask);
421
422 return (hash == hmask + 1 ?
423 &xfrm_policy_inexact[dir] :
424 xfrm_policy_bydst[dir].table + hash);
425 }
426
427 static struct hlist_head *policy_hash_direct(xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, int dir)
428 {
429 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
430 unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
431
432 return xfrm_policy_bydst[dir].table + hash;
433 }
434
435 static void xfrm_dst_hash_transfer(struct hlist_head *list,
436 struct hlist_head *ndsttable,
437 unsigned int nhashmask)
438 {
439 struct hlist_node *entry, *tmp;
440 struct xfrm_policy *pol;
441
442 hlist_for_each_entry_safe(pol, entry, tmp, list, bydst) {
443 unsigned int h;
444
445 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
446 pol->family, nhashmask);
447 hlist_add_head(&pol->bydst, ndsttable+h);
448 }
449 }
450
451 static void xfrm_idx_hash_transfer(struct hlist_head *list,
452 struct hlist_head *nidxtable,
453 unsigned int nhashmask)
454 {
455 struct hlist_node *entry, *tmp;
456 struct xfrm_policy *pol;
457
458 hlist_for_each_entry_safe(pol, entry, tmp, list, byidx) {
459 unsigned int h;
460
461 h = __idx_hash(pol->index, nhashmask);
462 hlist_add_head(&pol->byidx, nidxtable+h);
463 }
464 }
465
466 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
467 {
468 return ((old_hmask + 1) << 1) - 1;
469 }
470
471 static void xfrm_bydst_resize(int dir)
472 {
473 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
474 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
475 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
476 struct hlist_head *odst = xfrm_policy_bydst[dir].table;
477 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
478 int i;
479
480 if (!ndst)
481 return;
482
483 write_lock_bh(&xfrm_policy_lock);
484
485 for (i = hmask; i >= 0; i--)
486 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
487
488 xfrm_policy_bydst[dir].table = ndst;
489 xfrm_policy_bydst[dir].hmask = nhashmask;
490
491 write_unlock_bh(&xfrm_policy_lock);
492
493 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
494 }
495
496 static void xfrm_byidx_resize(int total)
497 {
498 unsigned int hmask = xfrm_idx_hmask;
499 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
500 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
501 struct hlist_head *oidx = xfrm_policy_byidx;
502 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
503 int i;
504
505 if (!nidx)
506 return;
507
508 write_lock_bh(&xfrm_policy_lock);
509
510 for (i = hmask; i >= 0; i--)
511 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
512
513 xfrm_policy_byidx = nidx;
514 xfrm_idx_hmask = nhashmask;
515
516 write_unlock_bh(&xfrm_policy_lock);
517
518 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
519 }
520
521 static inline int xfrm_bydst_should_resize(int dir, int *total)
522 {
523 unsigned int cnt = xfrm_policy_count[dir];
524 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
525
526 if (total)
527 *total += cnt;
528
529 if ((hmask + 1) < xfrm_policy_hashmax &&
530 cnt > hmask)
531 return 1;
532
533 return 0;
534 }
535
536 static inline int xfrm_byidx_should_resize(int total)
537 {
538 unsigned int hmask = xfrm_idx_hmask;
539
540 if ((hmask + 1) < xfrm_policy_hashmax &&
541 total > hmask)
542 return 1;
543
544 return 0;
545 }
546
547 static DEFINE_MUTEX(hash_resize_mutex);
548
549 static void xfrm_hash_resize(void *__unused)
550 {
551 int dir, total;
552
553 mutex_lock(&hash_resize_mutex);
554
555 total = 0;
556 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
557 if (xfrm_bydst_should_resize(dir, &total))
558 xfrm_bydst_resize(dir);
559 }
560 if (xfrm_byidx_should_resize(total))
561 xfrm_byidx_resize(total);
562
563 mutex_unlock(&hash_resize_mutex);
564 }
565
566 static DECLARE_WORK(xfrm_hash_work, xfrm_hash_resize, NULL);
567
568 /* Generate new index... KAME seems to generate them ordered by cost
569 * of an absolute inpredictability of ordering of rules. This will not pass. */
570 static u32 xfrm_gen_index(u8 type, int dir)
571 {
572 static u32 idx_generator;
573
574 for (;;) {
575 struct hlist_node *entry;
576 struct hlist_head *list;
577 struct xfrm_policy *p;
578 u32 idx;
579 int found;
580
581 idx = (idx_generator | dir);
582 idx_generator += 8;
583 if (idx == 0)
584 idx = 8;
585 list = xfrm_policy_byidx + idx_hash(idx);
586 found = 0;
587 hlist_for_each_entry(p, entry, list, byidx) {
588 if (p->index == idx) {
589 found = 1;
590 break;
591 }
592 }
593 if (!found)
594 return idx;
595 }
596 }
597
598 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
599 {
600 u32 *p1 = (u32 *) s1;
601 u32 *p2 = (u32 *) s2;
602 int len = sizeof(struct xfrm_selector) / sizeof(u32);
603 int i;
604
605 for (i = 0; i < len; i++) {
606 if (p1[i] != p2[i])
607 return 1;
608 }
609
610 return 0;
611 }
612
613 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
614 {
615 struct xfrm_policy *pol;
616 struct xfrm_policy *delpol;
617 struct hlist_head *chain;
618 struct hlist_node *entry, *newpos, *last;
619 struct dst_entry *gc_list;
620
621 write_lock_bh(&xfrm_policy_lock);
622 chain = policy_hash_bysel(&policy->selector, policy->family, dir);
623 delpol = NULL;
624 newpos = NULL;
625 last = NULL;
626 hlist_for_each_entry(pol, entry, chain, bydst) {
627 if (!delpol &&
628 pol->type == policy->type &&
629 !selector_cmp(&pol->selector, &policy->selector) &&
630 xfrm_sec_ctx_match(pol->security, policy->security)) {
631 if (excl) {
632 write_unlock_bh(&xfrm_policy_lock);
633 return -EEXIST;
634 }
635 delpol = pol;
636 if (policy->priority > pol->priority)
637 continue;
638 } else if (policy->priority >= pol->priority) {
639 last = &pol->bydst;
640 continue;
641 }
642 if (!newpos)
643 newpos = &pol->bydst;
644 if (delpol)
645 break;
646 last = &pol->bydst;
647 }
648 if (!newpos)
649 newpos = last;
650 if (newpos)
651 hlist_add_after(newpos, &policy->bydst);
652 else
653 hlist_add_head(&policy->bydst, chain);
654 xfrm_pol_hold(policy);
655 xfrm_policy_count[dir]++;
656 atomic_inc(&flow_cache_genid);
657 if (delpol) {
658 hlist_del(&delpol->bydst);
659 hlist_del(&delpol->byidx);
660 xfrm_policy_count[dir]--;
661 }
662 policy->index = delpol ? delpol->index : xfrm_gen_index(policy->type, dir);
663 hlist_add_head(&policy->byidx, xfrm_policy_byidx+idx_hash(policy->index));
664 policy->curlft.add_time = (unsigned long)xtime.tv_sec;
665 policy->curlft.use_time = 0;
666 if (!mod_timer(&policy->timer, jiffies + HZ))
667 xfrm_pol_hold(policy);
668 write_unlock_bh(&xfrm_policy_lock);
669
670 if (delpol)
671 xfrm_policy_kill(delpol);
672 else if (xfrm_bydst_should_resize(dir, NULL))
673 schedule_work(&xfrm_hash_work);
674
675 read_lock_bh(&xfrm_policy_lock);
676 gc_list = NULL;
677 entry = &policy->bydst;
678 hlist_for_each_entry_continue(policy, entry, bydst) {
679 struct dst_entry *dst;
680
681 write_lock(&policy->lock);
682 dst = policy->bundles;
683 if (dst) {
684 struct dst_entry *tail = dst;
685 while (tail->next)
686 tail = tail->next;
687 tail->next = gc_list;
688 gc_list = dst;
689
690 policy->bundles = NULL;
691 }
692 write_unlock(&policy->lock);
693 }
694 read_unlock_bh(&xfrm_policy_lock);
695
696 while (gc_list) {
697 struct dst_entry *dst = gc_list;
698
699 gc_list = dst->next;
700 dst_free(dst);
701 }
702
703 return 0;
704 }
705 EXPORT_SYMBOL(xfrm_policy_insert);
706
707 struct xfrm_policy *xfrm_policy_bysel_ctx(u8 type, int dir,
708 struct xfrm_selector *sel,
709 struct xfrm_sec_ctx *ctx, int delete)
710 {
711 struct xfrm_policy *pol, *ret;
712 struct hlist_head *chain;
713 struct hlist_node *entry;
714
715 write_lock_bh(&xfrm_policy_lock);
716 chain = policy_hash_bysel(sel, sel->family, dir);
717 ret = NULL;
718 hlist_for_each_entry(pol, entry, chain, bydst) {
719 if (pol->type == type &&
720 !selector_cmp(sel, &pol->selector) &&
721 xfrm_sec_ctx_match(ctx, pol->security)) {
722 xfrm_pol_hold(pol);
723 if (delete) {
724 hlist_del(&pol->bydst);
725 hlist_del(&pol->byidx);
726 xfrm_policy_count[dir]--;
727 }
728 ret = pol;
729 break;
730 }
731 }
732 write_unlock_bh(&xfrm_policy_lock);
733
734 if (ret && delete) {
735 atomic_inc(&flow_cache_genid);
736 xfrm_policy_kill(ret);
737 }
738 return ret;
739 }
740 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
741
742 struct xfrm_policy *xfrm_policy_byid(u8 type, int dir, u32 id, int delete)
743 {
744 struct xfrm_policy *pol, *ret;
745 struct hlist_head *chain;
746 struct hlist_node *entry;
747
748 write_lock_bh(&xfrm_policy_lock);
749 chain = xfrm_policy_byidx + idx_hash(id);
750 ret = NULL;
751 hlist_for_each_entry(pol, entry, chain, byidx) {
752 if (pol->type == type && pol->index == id) {
753 xfrm_pol_hold(pol);
754 if (delete) {
755 hlist_del(&pol->bydst);
756 hlist_del(&pol->byidx);
757 xfrm_policy_count[dir]--;
758 }
759 ret = pol;
760 break;
761 }
762 }
763 write_unlock_bh(&xfrm_policy_lock);
764
765 if (ret && delete) {
766 atomic_inc(&flow_cache_genid);
767 xfrm_policy_kill(ret);
768 }
769 return ret;
770 }
771 EXPORT_SYMBOL(xfrm_policy_byid);
772
773 void xfrm_policy_flush(u8 type)
774 {
775 int dir;
776
777 write_lock_bh(&xfrm_policy_lock);
778 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
779 struct xfrm_policy *pol;
780 struct hlist_node *entry;
781 int i, killed;
782
783 killed = 0;
784 again1:
785 hlist_for_each_entry(pol, entry,
786 &xfrm_policy_inexact[dir], bydst) {
787 if (pol->type != type)
788 continue;
789 hlist_del(&pol->bydst);
790 hlist_del(&pol->byidx);
791 write_unlock_bh(&xfrm_policy_lock);
792
793 xfrm_policy_kill(pol);
794 killed++;
795
796 write_lock_bh(&xfrm_policy_lock);
797 goto again1;
798 }
799
800 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
801 again2:
802 hlist_for_each_entry(pol, entry,
803 xfrm_policy_bydst[dir].table + i,
804 bydst) {
805 if (pol->type != type)
806 continue;
807 hlist_del(&pol->bydst);
808 hlist_del(&pol->byidx);
809 write_unlock_bh(&xfrm_policy_lock);
810
811 xfrm_policy_kill(pol);
812 killed++;
813
814 write_lock_bh(&xfrm_policy_lock);
815 goto again2;
816 }
817 }
818
819 xfrm_policy_count[dir] -= killed;
820 }
821 atomic_inc(&flow_cache_genid);
822 write_unlock_bh(&xfrm_policy_lock);
823 }
824 EXPORT_SYMBOL(xfrm_policy_flush);
825
826 int xfrm_policy_walk(u8 type, int (*func)(struct xfrm_policy *, int, int, void*),
827 void *data)
828 {
829 struct xfrm_policy *pol;
830 struct hlist_node *entry;
831 int dir, count, error;
832
833 read_lock_bh(&xfrm_policy_lock);
834 count = 0;
835 for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
836 struct hlist_head *table = xfrm_policy_bydst[dir].table;
837 int i;
838
839 hlist_for_each_entry(pol, entry,
840 &xfrm_policy_inexact[dir], bydst) {
841 if (pol->type == type)
842 count++;
843 }
844 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
845 hlist_for_each_entry(pol, entry, table + i, bydst) {
846 if (pol->type == type)
847 count++;
848 }
849 }
850 }
851
852 if (count == 0) {
853 error = -ENOENT;
854 goto out;
855 }
856
857 for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
858 struct hlist_head *table = xfrm_policy_bydst[dir].table;
859 int i;
860
861 hlist_for_each_entry(pol, entry,
862 &xfrm_policy_inexact[dir], bydst) {
863 if (pol->type != type)
864 continue;
865 error = func(pol, dir % XFRM_POLICY_MAX, --count, data);
866 if (error)
867 goto out;
868 }
869 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
870 hlist_for_each_entry(pol, entry, table + i, bydst) {
871 if (pol->type != type)
872 continue;
873 error = func(pol, dir % XFRM_POLICY_MAX, --count, data);
874 if (error)
875 goto out;
876 }
877 }
878 }
879 error = 0;
880 out:
881 read_unlock_bh(&xfrm_policy_lock);
882 return error;
883 }
884 EXPORT_SYMBOL(xfrm_policy_walk);
885
886 /* Find policy to apply to this flow. */
887
888 static int xfrm_policy_match(struct xfrm_policy *pol, struct flowi *fl,
889 u8 type, u16 family, int dir)
890 {
891 struct xfrm_selector *sel = &pol->selector;
892 int match;
893
894 if (pol->family != family ||
895 pol->type != type)
896 return 0;
897
898 match = xfrm_selector_match(sel, fl, family);
899 if (match) {
900 if (!security_xfrm_policy_lookup(pol, fl->secid, dir))
901 return 1;
902 }
903
904 return 0;
905 }
906
907 static struct xfrm_policy *xfrm_policy_lookup_bytype(u8 type, struct flowi *fl,
908 u16 family, u8 dir)
909 {
910 struct xfrm_policy *pol, *ret;
911 xfrm_address_t *daddr, *saddr;
912 struct hlist_node *entry;
913 struct hlist_head *chain;
914 u32 priority = ~0U;
915
916 daddr = xfrm_flowi_daddr(fl, family);
917 saddr = xfrm_flowi_saddr(fl, family);
918 if (unlikely(!daddr || !saddr))
919 return NULL;
920
921 read_lock_bh(&xfrm_policy_lock);
922 chain = policy_hash_direct(daddr, saddr, family, dir);
923 ret = NULL;
924 hlist_for_each_entry(pol, entry, chain, bydst) {
925 if (xfrm_policy_match(pol, fl, type, family, dir)) {
926 ret = pol;
927 priority = ret->priority;
928 break;
929 }
930 }
931 chain = &xfrm_policy_inexact[dir];
932 hlist_for_each_entry(pol, entry, chain, bydst) {
933 if (xfrm_policy_match(pol, fl, type, family, dir) &&
934 pol->priority < priority) {
935 ret = pol;
936 break;
937 }
938 }
939 if (ret)
940 xfrm_pol_hold(ret);
941 read_unlock_bh(&xfrm_policy_lock);
942
943 return ret;
944 }
945
946 static void xfrm_policy_lookup(struct flowi *fl, u16 family, u8 dir,
947 void **objp, atomic_t **obj_refp)
948 {
949 struct xfrm_policy *pol;
950
951 #ifdef CONFIG_XFRM_SUB_POLICY
952 pol = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_SUB, fl, family, dir);
953 if (pol)
954 goto end;
955 #endif
956 pol = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN, fl, family, dir);
957
958 #ifdef CONFIG_XFRM_SUB_POLICY
959 end:
960 #endif
961 if ((*objp = (void *) pol) != NULL)
962 *obj_refp = &pol->refcnt;
963 }
964
965 static inline int policy_to_flow_dir(int dir)
966 {
967 if (XFRM_POLICY_IN == FLOW_DIR_IN &&
968 XFRM_POLICY_OUT == FLOW_DIR_OUT &&
969 XFRM_POLICY_FWD == FLOW_DIR_FWD)
970 return dir;
971 switch (dir) {
972 default:
973 case XFRM_POLICY_IN:
974 return FLOW_DIR_IN;
975 case XFRM_POLICY_OUT:
976 return FLOW_DIR_OUT;
977 case XFRM_POLICY_FWD:
978 return FLOW_DIR_FWD;
979 };
980 }
981
982 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
983 {
984 struct xfrm_policy *pol;
985
986 read_lock_bh(&xfrm_policy_lock);
987 if ((pol = sk->sk_policy[dir]) != NULL) {
988 int match = xfrm_selector_match(&pol->selector, fl,
989 sk->sk_family);
990 int err = 0;
991
992 if (match)
993 err = security_xfrm_policy_lookup(pol, fl->secid, policy_to_flow_dir(dir));
994
995 if (match && !err)
996 xfrm_pol_hold(pol);
997 else
998 pol = NULL;
999 }
1000 read_unlock_bh(&xfrm_policy_lock);
1001 return pol;
1002 }
1003
1004 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1005 {
1006 struct hlist_head *chain = policy_hash_bysel(&pol->selector,
1007 pol->family, dir);
1008
1009 hlist_add_head(&pol->bydst, chain);
1010 hlist_add_head(&pol->byidx, xfrm_policy_byidx+idx_hash(pol->index));
1011 xfrm_policy_count[dir]++;
1012 xfrm_pol_hold(pol);
1013
1014 if (xfrm_bydst_should_resize(dir, NULL))
1015 schedule_work(&xfrm_hash_work);
1016 }
1017
1018 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1019 int dir)
1020 {
1021 if (hlist_unhashed(&pol->bydst))
1022 return NULL;
1023
1024 hlist_del(&pol->bydst);
1025 hlist_del(&pol->byidx);
1026 xfrm_policy_count[dir]--;
1027
1028 return pol;
1029 }
1030
1031 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1032 {
1033 write_lock_bh(&xfrm_policy_lock);
1034 pol = __xfrm_policy_unlink(pol, dir);
1035 write_unlock_bh(&xfrm_policy_lock);
1036 if (pol) {
1037 if (dir < XFRM_POLICY_MAX)
1038 atomic_inc(&flow_cache_genid);
1039 xfrm_policy_kill(pol);
1040 return 0;
1041 }
1042 return -ENOENT;
1043 }
1044 EXPORT_SYMBOL(xfrm_policy_delete);
1045
1046 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1047 {
1048 struct xfrm_policy *old_pol;
1049
1050 #ifdef CONFIG_XFRM_SUB_POLICY
1051 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1052 return -EINVAL;
1053 #endif
1054
1055 write_lock_bh(&xfrm_policy_lock);
1056 old_pol = sk->sk_policy[dir];
1057 sk->sk_policy[dir] = pol;
1058 if (pol) {
1059 pol->curlft.add_time = (unsigned long)xtime.tv_sec;
1060 pol->index = xfrm_gen_index(pol->type, XFRM_POLICY_MAX+dir);
1061 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1062 }
1063 if (old_pol)
1064 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1065 write_unlock_bh(&xfrm_policy_lock);
1066
1067 if (old_pol) {
1068 xfrm_policy_kill(old_pol);
1069 }
1070 return 0;
1071 }
1072
1073 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
1074 {
1075 struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC);
1076
1077 if (newp) {
1078 newp->selector = old->selector;
1079 if (security_xfrm_policy_clone(old, newp)) {
1080 kfree(newp);
1081 return NULL; /* ENOMEM */
1082 }
1083 newp->lft = old->lft;
1084 newp->curlft = old->curlft;
1085 newp->action = old->action;
1086 newp->flags = old->flags;
1087 newp->xfrm_nr = old->xfrm_nr;
1088 newp->index = old->index;
1089 newp->type = old->type;
1090 memcpy(newp->xfrm_vec, old->xfrm_vec,
1091 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1092 write_lock_bh(&xfrm_policy_lock);
1093 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1094 write_unlock_bh(&xfrm_policy_lock);
1095 xfrm_pol_put(newp);
1096 }
1097 return newp;
1098 }
1099
1100 int __xfrm_sk_clone_policy(struct sock *sk)
1101 {
1102 struct xfrm_policy *p0 = sk->sk_policy[0],
1103 *p1 = sk->sk_policy[1];
1104
1105 sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1106 if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1107 return -ENOMEM;
1108 if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1109 return -ENOMEM;
1110 return 0;
1111 }
1112
1113 static int
1114 xfrm_get_saddr(xfrm_address_t *local, xfrm_address_t *remote,
1115 unsigned short family)
1116 {
1117 int err;
1118 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1119
1120 if (unlikely(afinfo == NULL))
1121 return -EINVAL;
1122 err = afinfo->get_saddr(local, remote);
1123 xfrm_policy_put_afinfo(afinfo);
1124 return err;
1125 }
1126
1127 /* Resolve list of templates for the flow, given policy. */
1128
1129 static int
1130 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, struct flowi *fl,
1131 struct xfrm_state **xfrm,
1132 unsigned short family)
1133 {
1134 int nx;
1135 int i, error;
1136 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1137 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1138 xfrm_address_t tmp;
1139
1140 for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1141 struct xfrm_state *x;
1142 xfrm_address_t *remote = daddr;
1143 xfrm_address_t *local = saddr;
1144 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1145
1146 if (tmpl->mode == XFRM_MODE_TUNNEL) {
1147 remote = &tmpl->id.daddr;
1148 local = &tmpl->saddr;
1149 if (xfrm_addr_any(local, family)) {
1150 error = xfrm_get_saddr(&tmp, remote, family);
1151 if (error)
1152 goto fail;
1153 local = &tmp;
1154 }
1155 }
1156
1157 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1158
1159 if (x && x->km.state == XFRM_STATE_VALID) {
1160 xfrm[nx++] = x;
1161 daddr = remote;
1162 saddr = local;
1163 continue;
1164 }
1165 if (x) {
1166 error = (x->km.state == XFRM_STATE_ERROR ?
1167 -EINVAL : -EAGAIN);
1168 xfrm_state_put(x);
1169 }
1170
1171 if (!tmpl->optional)
1172 goto fail;
1173 }
1174 return nx;
1175
1176 fail:
1177 for (nx--; nx>=0; nx--)
1178 xfrm_state_put(xfrm[nx]);
1179 return error;
1180 }
1181
1182 static int
1183 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
1184 struct xfrm_state **xfrm,
1185 unsigned short family)
1186 {
1187 struct xfrm_state *tp[XFRM_MAX_DEPTH];
1188 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1189 int cnx = 0;
1190 int error;
1191 int ret;
1192 int i;
1193
1194 for (i = 0; i < npols; i++) {
1195 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1196 error = -ENOBUFS;
1197 goto fail;
1198 }
1199
1200 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1201 if (ret < 0) {
1202 error = ret;
1203 goto fail;
1204 } else
1205 cnx += ret;
1206 }
1207
1208 /* found states are sorted for outbound processing */
1209 if (npols > 1)
1210 xfrm_state_sort(xfrm, tpp, cnx, family);
1211
1212 return cnx;
1213
1214 fail:
1215 for (cnx--; cnx>=0; cnx--)
1216 xfrm_state_put(tpp[cnx]);
1217 return error;
1218
1219 }
1220
1221 /* Check that the bundle accepts the flow and its components are
1222 * still valid.
1223 */
1224
1225 static struct dst_entry *
1226 xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family)
1227 {
1228 struct dst_entry *x;
1229 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1230 if (unlikely(afinfo == NULL))
1231 return ERR_PTR(-EINVAL);
1232 x = afinfo->find_bundle(fl, policy);
1233 xfrm_policy_put_afinfo(afinfo);
1234 return x;
1235 }
1236
1237 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1238 * all the metrics... Shortly, bundle a bundle.
1239 */
1240
1241 static int
1242 xfrm_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx,
1243 struct flowi *fl, struct dst_entry **dst_p,
1244 unsigned short family)
1245 {
1246 int err;
1247 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1248 if (unlikely(afinfo == NULL))
1249 return -EINVAL;
1250 err = afinfo->bundle_create(policy, xfrm, nx, fl, dst_p);
1251 xfrm_policy_put_afinfo(afinfo);
1252 return err;
1253 }
1254
1255
1256 static int stale_bundle(struct dst_entry *dst);
1257
1258 /* Main function: finds/creates a bundle for given flow.
1259 *
1260 * At the moment we eat a raw IP route. Mostly to speed up lookups
1261 * on interfaces with disabled IPsec.
1262 */
1263 int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl,
1264 struct sock *sk, int flags)
1265 {
1266 struct xfrm_policy *policy;
1267 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1268 int npols;
1269 int pol_dead;
1270 int xfrm_nr;
1271 int pi;
1272 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1273 struct dst_entry *dst, *dst_orig = *dst_p;
1274 int nx = 0;
1275 int err;
1276 u32 genid;
1277 u16 family;
1278 u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
1279
1280 restart:
1281 genid = atomic_read(&flow_cache_genid);
1282 policy = NULL;
1283 for (pi = 0; pi < ARRAY_SIZE(pols); pi++)
1284 pols[pi] = NULL;
1285 npols = 0;
1286 pol_dead = 0;
1287 xfrm_nr = 0;
1288
1289 if (sk && sk->sk_policy[1])
1290 policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
1291
1292 if (!policy) {
1293 /* To accelerate a bit... */
1294 if ((dst_orig->flags & DST_NOXFRM) ||
1295 !xfrm_policy_count[XFRM_POLICY_OUT])
1296 return 0;
1297
1298 policy = flow_cache_lookup(fl, dst_orig->ops->family,
1299 dir, xfrm_policy_lookup);
1300 }
1301
1302 if (!policy)
1303 return 0;
1304
1305 family = dst_orig->ops->family;
1306 policy->curlft.use_time = (unsigned long)xtime.tv_sec;
1307 pols[0] = policy;
1308 npols ++;
1309 xfrm_nr += pols[0]->xfrm_nr;
1310
1311 switch (policy->action) {
1312 case XFRM_POLICY_BLOCK:
1313 /* Prohibit the flow */
1314 err = -EPERM;
1315 goto error;
1316
1317 case XFRM_POLICY_ALLOW:
1318 #ifndef CONFIG_XFRM_SUB_POLICY
1319 if (policy->xfrm_nr == 0) {
1320 /* Flow passes not transformed. */
1321 xfrm_pol_put(policy);
1322 return 0;
1323 }
1324 #endif
1325
1326 /* Try to find matching bundle.
1327 *
1328 * LATER: help from flow cache. It is optional, this
1329 * is required only for output policy.
1330 */
1331 dst = xfrm_find_bundle(fl, policy, family);
1332 if (IS_ERR(dst)) {
1333 err = PTR_ERR(dst);
1334 goto error;
1335 }
1336
1337 if (dst)
1338 break;
1339
1340 #ifdef CONFIG_XFRM_SUB_POLICY
1341 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1342 pols[1] = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN,
1343 fl, family,
1344 XFRM_POLICY_OUT);
1345 if (pols[1]) {
1346 if (pols[1]->action == XFRM_POLICY_BLOCK) {
1347 err = -EPERM;
1348 goto error;
1349 }
1350 npols ++;
1351 xfrm_nr += pols[1]->xfrm_nr;
1352 }
1353 }
1354
1355 /*
1356 * Because neither flowi nor bundle information knows about
1357 * transformation template size. On more than one policy usage
1358 * we can realize whether all of them is bypass or not after
1359 * they are searched. See above not-transformed bypass
1360 * is surrounded by non-sub policy configuration, too.
1361 */
1362 if (xfrm_nr == 0) {
1363 /* Flow passes not transformed. */
1364 xfrm_pols_put(pols, npols);
1365 return 0;
1366 }
1367
1368 #endif
1369 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1370
1371 if (unlikely(nx<0)) {
1372 err = nx;
1373 if (err == -EAGAIN && flags) {
1374 DECLARE_WAITQUEUE(wait, current);
1375
1376 add_wait_queue(&km_waitq, &wait);
1377 set_current_state(TASK_INTERRUPTIBLE);
1378 schedule();
1379 set_current_state(TASK_RUNNING);
1380 remove_wait_queue(&km_waitq, &wait);
1381
1382 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1383
1384 if (nx == -EAGAIN && signal_pending(current)) {
1385 err = -ERESTART;
1386 goto error;
1387 }
1388 if (nx == -EAGAIN ||
1389 genid != atomic_read(&flow_cache_genid)) {
1390 xfrm_pols_put(pols, npols);
1391 goto restart;
1392 }
1393 err = nx;
1394 }
1395 if (err < 0)
1396 goto error;
1397 }
1398 if (nx == 0) {
1399 /* Flow passes not transformed. */
1400 xfrm_pols_put(pols, npols);
1401 return 0;
1402 }
1403
1404 dst = dst_orig;
1405 err = xfrm_bundle_create(policy, xfrm, nx, fl, &dst, family);
1406
1407 if (unlikely(err)) {
1408 int i;
1409 for (i=0; i<nx; i++)
1410 xfrm_state_put(xfrm[i]);
1411 goto error;
1412 }
1413
1414 for (pi = 0; pi < npols; pi++) {
1415 read_lock_bh(&pols[pi]->lock);
1416 pol_dead |= pols[pi]->dead;
1417 read_unlock_bh(&pols[pi]->lock);
1418 }
1419
1420 write_lock_bh(&policy->lock);
1421 if (unlikely(pol_dead || stale_bundle(dst))) {
1422 /* Wow! While we worked on resolving, this
1423 * policy has gone. Retry. It is not paranoia,
1424 * we just cannot enlist new bundle to dead object.
1425 * We can't enlist stable bundles either.
1426 */
1427 write_unlock_bh(&policy->lock);
1428 if (dst)
1429 dst_free(dst);
1430
1431 err = -EHOSTUNREACH;
1432 goto error;
1433 }
1434 dst->next = policy->bundles;
1435 policy->bundles = dst;
1436 dst_hold(dst);
1437 write_unlock_bh(&policy->lock);
1438 }
1439 *dst_p = dst;
1440 dst_release(dst_orig);
1441 xfrm_pols_put(pols, npols);
1442 return 0;
1443
1444 error:
1445 dst_release(dst_orig);
1446 xfrm_pols_put(pols, npols);
1447 *dst_p = NULL;
1448 return err;
1449 }
1450 EXPORT_SYMBOL(xfrm_lookup);
1451
1452 static inline int
1453 xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
1454 {
1455 struct xfrm_state *x;
1456 int err;
1457
1458 if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1459 return 0;
1460 x = skb->sp->xvec[idx];
1461 if (!x->type->reject)
1462 return 0;
1463 xfrm_state_hold(x);
1464 err = x->type->reject(x, skb, fl);
1465 xfrm_state_put(x);
1466 return err;
1467 }
1468
1469 /* When skb is transformed back to its "native" form, we have to
1470 * check policy restrictions. At the moment we make this in maximally
1471 * stupid way. Shame on me. :-) Of course, connected sockets must
1472 * have policy cached at them.
1473 */
1474
1475 static inline int
1476 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
1477 unsigned short family)
1478 {
1479 if (xfrm_state_kern(x))
1480 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, family);
1481 return x->id.proto == tmpl->id.proto &&
1482 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1483 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1484 x->props.mode == tmpl->mode &&
1485 ((tmpl->aalgos & (1<<x->props.aalgo)) ||
1486 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1487 !(x->props.mode != XFRM_MODE_TRANSPORT &&
1488 xfrm_state_addr_cmp(tmpl, x, family));
1489 }
1490
1491 /*
1492 * 0 or more than 0 is returned when validation is succeeded (either bypass
1493 * because of optional transport mode, or next index of the mathced secpath
1494 * state with the template.
1495 * -1 is returned when no matching template is found.
1496 * Otherwise "-2 - errored_index" is returned.
1497 */
1498 static inline int
1499 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1500 unsigned short family)
1501 {
1502 int idx = start;
1503
1504 if (tmpl->optional) {
1505 if (tmpl->mode == XFRM_MODE_TRANSPORT)
1506 return start;
1507 } else
1508 start = -1;
1509 for (; idx < sp->len; idx++) {
1510 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1511 return ++idx;
1512 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
1513 if (start == -1)
1514 start = -2-idx;
1515 break;
1516 }
1517 }
1518 return start;
1519 }
1520
1521 int
1522 xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family)
1523 {
1524 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1525 int err;
1526
1527 if (unlikely(afinfo == NULL))
1528 return -EAFNOSUPPORT;
1529
1530 afinfo->decode_session(skb, fl);
1531 err = security_xfrm_decode_session(skb, &fl->secid);
1532 xfrm_policy_put_afinfo(afinfo);
1533 return err;
1534 }
1535 EXPORT_SYMBOL(xfrm_decode_session);
1536
1537 static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
1538 {
1539 for (; k < sp->len; k++) {
1540 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
1541 *idxp = k;
1542 return 1;
1543 }
1544 }
1545
1546 return 0;
1547 }
1548
1549 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
1550 unsigned short family)
1551 {
1552 struct xfrm_policy *pol;
1553 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1554 int npols = 0;
1555 int xfrm_nr;
1556 int pi;
1557 struct flowi fl;
1558 u8 fl_dir = policy_to_flow_dir(dir);
1559 int xerr_idx = -1;
1560
1561 if (xfrm_decode_session(skb, &fl, family) < 0)
1562 return 0;
1563 nf_nat_decode_session(skb, &fl, family);
1564
1565 /* First, check used SA against their selectors. */
1566 if (skb->sp) {
1567 int i;
1568
1569 for (i=skb->sp->len-1; i>=0; i--) {
1570 struct xfrm_state *x = skb->sp->xvec[i];
1571 if (!xfrm_selector_match(&x->sel, &fl, family))
1572 return 0;
1573 }
1574 }
1575
1576 pol = NULL;
1577 if (sk && sk->sk_policy[dir])
1578 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
1579
1580 if (!pol)
1581 pol = flow_cache_lookup(&fl, family, fl_dir,
1582 xfrm_policy_lookup);
1583
1584 if (!pol) {
1585 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
1586 xfrm_secpath_reject(xerr_idx, skb, &fl);
1587 return 0;
1588 }
1589 return 1;
1590 }
1591
1592 pol->curlft.use_time = (unsigned long)xtime.tv_sec;
1593
1594 pols[0] = pol;
1595 npols ++;
1596 #ifdef CONFIG_XFRM_SUB_POLICY
1597 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1598 pols[1] = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN,
1599 &fl, family,
1600 XFRM_POLICY_IN);
1601 if (pols[1]) {
1602 pols[1]->curlft.use_time = (unsigned long)xtime.tv_sec;
1603 npols ++;
1604 }
1605 }
1606 #endif
1607
1608 if (pol->action == XFRM_POLICY_ALLOW) {
1609 struct sec_path *sp;
1610 static struct sec_path dummy;
1611 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
1612 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
1613 struct xfrm_tmpl **tpp = tp;
1614 int ti = 0;
1615 int i, k;
1616
1617 if ((sp = skb->sp) == NULL)
1618 sp = &dummy;
1619
1620 for (pi = 0; pi < npols; pi++) {
1621 if (pols[pi] != pol &&
1622 pols[pi]->action != XFRM_POLICY_ALLOW)
1623 goto reject;
1624 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH)
1625 goto reject_error;
1626 for (i = 0; i < pols[pi]->xfrm_nr; i++)
1627 tpp[ti++] = &pols[pi]->xfrm_vec[i];
1628 }
1629 xfrm_nr = ti;
1630 if (npols > 1) {
1631 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
1632 tpp = stp;
1633 }
1634
1635 /* For each tunnel xfrm, find the first matching tmpl.
1636 * For each tmpl before that, find corresponding xfrm.
1637 * Order is _important_. Later we will implement
1638 * some barriers, but at the moment barriers
1639 * are implied between each two transformations.
1640 */
1641 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
1642 k = xfrm_policy_ok(tpp[i], sp, k, family);
1643 if (k < 0) {
1644 if (k < -1)
1645 /* "-2 - errored_index" returned */
1646 xerr_idx = -(2+k);
1647 goto reject;
1648 }
1649 }
1650
1651 if (secpath_has_nontransport(sp, k, &xerr_idx))
1652 goto reject;
1653
1654 xfrm_pols_put(pols, npols);
1655 return 1;
1656 }
1657
1658 reject:
1659 xfrm_secpath_reject(xerr_idx, skb, &fl);
1660 reject_error:
1661 xfrm_pols_put(pols, npols);
1662 return 0;
1663 }
1664 EXPORT_SYMBOL(__xfrm_policy_check);
1665
1666 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1667 {
1668 struct flowi fl;
1669
1670 if (xfrm_decode_session(skb, &fl, family) < 0)
1671 return 0;
1672
1673 return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0;
1674 }
1675 EXPORT_SYMBOL(__xfrm_route_forward);
1676
1677 /* Optimize later using cookies and generation ids. */
1678
1679 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
1680 {
1681 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
1682 * to "-1" to force all XFRM destinations to get validated by
1683 * dst_ops->check on every use. We do this because when a
1684 * normal route referenced by an XFRM dst is obsoleted we do
1685 * not go looking around for all parent referencing XFRM dsts
1686 * so that we can invalidate them. It is just too much work.
1687 * Instead we make the checks here on every use. For example:
1688 *
1689 * XFRM dst A --> IPv4 dst X
1690 *
1691 * X is the "xdst->route" of A (X is also the "dst->path" of A
1692 * in this example). If X is marked obsolete, "A" will not
1693 * notice. That's what we are validating here via the
1694 * stale_bundle() check.
1695 *
1696 * When a policy's bundle is pruned, we dst_free() the XFRM
1697 * dst which causes it's ->obsolete field to be set to a
1698 * positive non-zero integer. If an XFRM dst has been pruned
1699 * like this, we want to force a new route lookup.
1700 */
1701 if (dst->obsolete < 0 && !stale_bundle(dst))
1702 return dst;
1703
1704 return NULL;
1705 }
1706
1707 static int stale_bundle(struct dst_entry *dst)
1708 {
1709 return !xfrm_bundle_ok((struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
1710 }
1711
1712 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
1713 {
1714 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
1715 dst->dev = &loopback_dev;
1716 dev_hold(&loopback_dev);
1717 dev_put(dev);
1718 }
1719 }
1720 EXPORT_SYMBOL(xfrm_dst_ifdown);
1721
1722 static void xfrm_link_failure(struct sk_buff *skb)
1723 {
1724 /* Impossible. Such dst must be popped before reaches point of failure. */
1725 return;
1726 }
1727
1728 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
1729 {
1730 if (dst) {
1731 if (dst->obsolete) {
1732 dst_release(dst);
1733 dst = NULL;
1734 }
1735 }
1736 return dst;
1737 }
1738
1739 static void prune_one_bundle(struct xfrm_policy *pol, int (*func)(struct dst_entry *), struct dst_entry **gc_list_p)
1740 {
1741 struct dst_entry *dst, **dstp;
1742
1743 write_lock(&pol->lock);
1744 dstp = &pol->bundles;
1745 while ((dst=*dstp) != NULL) {
1746 if (func(dst)) {
1747 *dstp = dst->next;
1748 dst->next = *gc_list_p;
1749 *gc_list_p = dst;
1750 } else {
1751 dstp = &dst->next;
1752 }
1753 }
1754 write_unlock(&pol->lock);
1755 }
1756
1757 static void xfrm_prune_bundles(int (*func)(struct dst_entry *))
1758 {
1759 struct dst_entry *gc_list = NULL;
1760 int dir;
1761
1762 read_lock_bh(&xfrm_policy_lock);
1763 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
1764 struct xfrm_policy *pol;
1765 struct hlist_node *entry;
1766 struct hlist_head *table;
1767 int i;
1768
1769 hlist_for_each_entry(pol, entry,
1770 &xfrm_policy_inexact[dir], bydst)
1771 prune_one_bundle(pol, func, &gc_list);
1772
1773 table = xfrm_policy_bydst[dir].table;
1774 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
1775 hlist_for_each_entry(pol, entry, table + i, bydst)
1776 prune_one_bundle(pol, func, &gc_list);
1777 }
1778 }
1779 read_unlock_bh(&xfrm_policy_lock);
1780
1781 while (gc_list) {
1782 struct dst_entry *dst = gc_list;
1783 gc_list = dst->next;
1784 dst_free(dst);
1785 }
1786 }
1787
1788 static int unused_bundle(struct dst_entry *dst)
1789 {
1790 return !atomic_read(&dst->__refcnt);
1791 }
1792
1793 static void __xfrm_garbage_collect(void)
1794 {
1795 xfrm_prune_bundles(unused_bundle);
1796 }
1797
1798 static int xfrm_flush_bundles(void)
1799 {
1800 xfrm_prune_bundles(stale_bundle);
1801 return 0;
1802 }
1803
1804 void xfrm_init_pmtu(struct dst_entry *dst)
1805 {
1806 do {
1807 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1808 u32 pmtu, route_mtu_cached;
1809
1810 pmtu = dst_mtu(dst->child);
1811 xdst->child_mtu_cached = pmtu;
1812
1813 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
1814
1815 route_mtu_cached = dst_mtu(xdst->route);
1816 xdst->route_mtu_cached = route_mtu_cached;
1817
1818 if (pmtu > route_mtu_cached)
1819 pmtu = route_mtu_cached;
1820
1821 dst->metrics[RTAX_MTU-1] = pmtu;
1822 } while ((dst = dst->next));
1823 }
1824
1825 EXPORT_SYMBOL(xfrm_init_pmtu);
1826
1827 /* Check that the bundle accepts the flow and its components are
1828 * still valid.
1829 */
1830
1831 int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family, int strict)
1832 {
1833 struct dst_entry *dst = &first->u.dst;
1834 struct xfrm_dst *last;
1835 u32 mtu;
1836
1837 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
1838 (dst->dev && !netif_running(dst->dev)))
1839 return 0;
1840
1841 last = NULL;
1842
1843 do {
1844 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1845
1846 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
1847 return 0;
1848 if (fl && !security_xfrm_flow_state_match(fl, dst->xfrm))
1849 return 0;
1850 if (dst->xfrm->km.state != XFRM_STATE_VALID)
1851 return 0;
1852 if (xdst->genid != dst->xfrm->genid)
1853 return 0;
1854
1855 if (strict && fl && dst->xfrm->props.mode != XFRM_MODE_TUNNEL &&
1856 !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
1857 return 0;
1858
1859 mtu = dst_mtu(dst->child);
1860 if (xdst->child_mtu_cached != mtu) {
1861 last = xdst;
1862 xdst->child_mtu_cached = mtu;
1863 }
1864
1865 if (!dst_check(xdst->route, xdst->route_cookie))
1866 return 0;
1867 mtu = dst_mtu(xdst->route);
1868 if (xdst->route_mtu_cached != mtu) {
1869 last = xdst;
1870 xdst->route_mtu_cached = mtu;
1871 }
1872
1873 dst = dst->child;
1874 } while (dst->xfrm);
1875
1876 if (likely(!last))
1877 return 1;
1878
1879 mtu = last->child_mtu_cached;
1880 for (;;) {
1881 dst = &last->u.dst;
1882
1883 mtu = xfrm_state_mtu(dst->xfrm, mtu);
1884 if (mtu > last->route_mtu_cached)
1885 mtu = last->route_mtu_cached;
1886 dst->metrics[RTAX_MTU-1] = mtu;
1887
1888 if (last == first)
1889 break;
1890
1891 last = last->u.next;
1892 last->child_mtu_cached = mtu;
1893 }
1894
1895 return 1;
1896 }
1897
1898 EXPORT_SYMBOL(xfrm_bundle_ok);
1899
1900 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
1901 {
1902 int err = 0;
1903 if (unlikely(afinfo == NULL))
1904 return -EINVAL;
1905 if (unlikely(afinfo->family >= NPROTO))
1906 return -EAFNOSUPPORT;
1907 write_lock_bh(&xfrm_policy_afinfo_lock);
1908 if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
1909 err = -ENOBUFS;
1910 else {
1911 struct dst_ops *dst_ops = afinfo->dst_ops;
1912 if (likely(dst_ops->kmem_cachep == NULL))
1913 dst_ops->kmem_cachep = xfrm_dst_cache;
1914 if (likely(dst_ops->check == NULL))
1915 dst_ops->check = xfrm_dst_check;
1916 if (likely(dst_ops->negative_advice == NULL))
1917 dst_ops->negative_advice = xfrm_negative_advice;
1918 if (likely(dst_ops->link_failure == NULL))
1919 dst_ops->link_failure = xfrm_link_failure;
1920 if (likely(afinfo->garbage_collect == NULL))
1921 afinfo->garbage_collect = __xfrm_garbage_collect;
1922 xfrm_policy_afinfo[afinfo->family] = afinfo;
1923 }
1924 write_unlock_bh(&xfrm_policy_afinfo_lock);
1925 return err;
1926 }
1927 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
1928
1929 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
1930 {
1931 int err = 0;
1932 if (unlikely(afinfo == NULL))
1933 return -EINVAL;
1934 if (unlikely(afinfo->family >= NPROTO))
1935 return -EAFNOSUPPORT;
1936 write_lock_bh(&xfrm_policy_afinfo_lock);
1937 if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
1938 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
1939 err = -EINVAL;
1940 else {
1941 struct dst_ops *dst_ops = afinfo->dst_ops;
1942 xfrm_policy_afinfo[afinfo->family] = NULL;
1943 dst_ops->kmem_cachep = NULL;
1944 dst_ops->check = NULL;
1945 dst_ops->negative_advice = NULL;
1946 dst_ops->link_failure = NULL;
1947 afinfo->garbage_collect = NULL;
1948 }
1949 }
1950 write_unlock_bh(&xfrm_policy_afinfo_lock);
1951 return err;
1952 }
1953 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
1954
1955 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
1956 {
1957 struct xfrm_policy_afinfo *afinfo;
1958 if (unlikely(family >= NPROTO))
1959 return NULL;
1960 read_lock(&xfrm_policy_afinfo_lock);
1961 afinfo = xfrm_policy_afinfo[family];
1962 if (unlikely(!afinfo))
1963 read_unlock(&xfrm_policy_afinfo_lock);
1964 return afinfo;
1965 }
1966
1967 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
1968 {
1969 read_unlock(&xfrm_policy_afinfo_lock);
1970 }
1971
1972 static struct xfrm_policy_afinfo *xfrm_policy_lock_afinfo(unsigned int family)
1973 {
1974 struct xfrm_policy_afinfo *afinfo;
1975 if (unlikely(family >= NPROTO))
1976 return NULL;
1977 write_lock_bh(&xfrm_policy_afinfo_lock);
1978 afinfo = xfrm_policy_afinfo[family];
1979 if (unlikely(!afinfo))
1980 write_unlock_bh(&xfrm_policy_afinfo_lock);
1981 return afinfo;
1982 }
1983
1984 static void xfrm_policy_unlock_afinfo(struct xfrm_policy_afinfo *afinfo)
1985 {
1986 write_unlock_bh(&xfrm_policy_afinfo_lock);
1987 }
1988
1989 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
1990 {
1991 switch (event) {
1992 case NETDEV_DOWN:
1993 xfrm_flush_bundles();
1994 }
1995 return NOTIFY_DONE;
1996 }
1997
1998 static struct notifier_block xfrm_dev_notifier = {
1999 xfrm_dev_event,
2000 NULL,
2001 0
2002 };
2003
2004 static void __init xfrm_policy_init(void)
2005 {
2006 unsigned int hmask, sz;
2007 int dir;
2008
2009 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2010 sizeof(struct xfrm_dst),
2011 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2012 NULL, NULL);
2013
2014 hmask = 8 - 1;
2015 sz = (hmask+1) * sizeof(struct hlist_head);
2016
2017 xfrm_policy_byidx = xfrm_hash_alloc(sz);
2018 xfrm_idx_hmask = hmask;
2019 if (!xfrm_policy_byidx)
2020 panic("XFRM: failed to allocate byidx hash\n");
2021
2022 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2023 struct xfrm_policy_hash *htab;
2024
2025 INIT_HLIST_HEAD(&xfrm_policy_inexact[dir]);
2026
2027 htab = &xfrm_policy_bydst[dir];
2028 htab->table = xfrm_hash_alloc(sz);
2029 htab->hmask = hmask;
2030 if (!htab->table)
2031 panic("XFRM: failed to allocate bydst hash\n");
2032 }
2033
2034 INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task, NULL);
2035 register_netdevice_notifier(&xfrm_dev_notifier);
2036 }
2037
2038 void __init xfrm_init(void)
2039 {
2040 xfrm_state_init();
2041 xfrm_policy_init();
2042 xfrm_input_init();
2043 }
2044
kernel source for telekom puls (alcatel/mediatek)