Merge rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / 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/config.h>
17 #include <linux/slab.h>
18 #include <linux/kmod.h>
19 #include <linux/list.h>
20 #include <linux/spinlock.h>
21 #include <linux/workqueue.h>
22 #include <linux/notifier.h>
23 #include <linux/netdevice.h>
24 #include <linux/netfilter.h>
25 #include <linux/module.h>
26 #include <net/xfrm.h>
27 #include <net/ip.h>
28
29 DEFINE_MUTEX(xfrm_cfg_mutex);
30 EXPORT_SYMBOL(xfrm_cfg_mutex);
31
32 static DEFINE_RWLOCK(xfrm_policy_lock);
33
34 struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2];
35 EXPORT_SYMBOL(xfrm_policy_list);
36
37 static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
38 static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
39
40 static kmem_cache_t *xfrm_dst_cache __read_mostly;
41
42 static struct work_struct xfrm_policy_gc_work;
43 static struct list_head xfrm_policy_gc_list =
44         LIST_HEAD_INIT(xfrm_policy_gc_list);
45 static DEFINE_SPINLOCK(xfrm_policy_gc_lock);
46
47 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
48 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
49 static struct xfrm_policy_afinfo *xfrm_policy_lock_afinfo(unsigned int family);
50 static void xfrm_policy_unlock_afinfo(struct xfrm_policy_afinfo *afinfo);
51
52 int xfrm_register_type(struct xfrm_type *type, unsigned short family)
53 {
54         struct xfrm_policy_afinfo *afinfo = xfrm_policy_lock_afinfo(family);
55         struct xfrm_type **typemap;
56         int err = 0;
57
58         if (unlikely(afinfo == NULL))
59                 return -EAFNOSUPPORT;
60         typemap = afinfo->type_map;
61
62         if (likely(typemap[type->proto] == NULL))
63                 typemap[type->proto] = type;
64         else
65                 err = -EEXIST;
66         xfrm_policy_unlock_afinfo(afinfo);
67         return err;
68 }
69 EXPORT_SYMBOL(xfrm_register_type);
70
71 int xfrm_unregister_type(struct xfrm_type *type, unsigned short family)
72 {
73         struct xfrm_policy_afinfo *afinfo = xfrm_policy_lock_afinfo(family);
74         struct xfrm_type **typemap;
75         int err = 0;
76
77         if (unlikely(afinfo == NULL))
78                 return -EAFNOSUPPORT;
79         typemap = afinfo->type_map;
80
81         if (unlikely(typemap[type->proto] != type))
82                 err = -ENOENT;
83         else
84                 typemap[type->proto] = NULL;
85         xfrm_policy_unlock_afinfo(afinfo);
86         return err;
87 }
88 EXPORT_SYMBOL(xfrm_unregister_type);
89
90 struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family)
91 {
92         struct xfrm_policy_afinfo *afinfo;
93         struct xfrm_type **typemap;
94         struct xfrm_type *type;
95         int modload_attempted = 0;
96
97 retry:
98         afinfo = xfrm_policy_get_afinfo(family);
99         if (unlikely(afinfo == NULL))
100                 return NULL;
101         typemap = afinfo->type_map;
102
103         type = typemap[proto];
104         if (unlikely(type && !try_module_get(type->owner)))
105                 type = NULL;
106         if (!type && !modload_attempted) {
107                 xfrm_policy_put_afinfo(afinfo);
108                 request_module("xfrm-type-%d-%d",
109                                (int) family, (int) proto);
110                 modload_attempted = 1;
111                 goto retry;
112         }
113
114         xfrm_policy_put_afinfo(afinfo);
115         return type;
116 }
117
118 int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, 
119                     unsigned short family)
120 {
121         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
122         int err = 0;
123
124         if (unlikely(afinfo == NULL))
125                 return -EAFNOSUPPORT;
126
127         if (likely(afinfo->dst_lookup != NULL))
128                 err = afinfo->dst_lookup(dst, fl);
129         else
130                 err = -EINVAL;
131         xfrm_policy_put_afinfo(afinfo);
132         return err;
133 }
134 EXPORT_SYMBOL(xfrm_dst_lookup);
135
136 void xfrm_put_type(struct xfrm_type *type)
137 {
138         module_put(type->owner);
139 }
140
141 int xfrm_register_mode(struct xfrm_mode *mode, int family)
142 {
143         struct xfrm_policy_afinfo *afinfo;
144         struct xfrm_mode **modemap;
145         int err;
146
147         if (unlikely(mode->encap >= XFRM_MODE_MAX))
148                 return -EINVAL;
149
150         afinfo = xfrm_policy_lock_afinfo(family);
151         if (unlikely(afinfo == NULL))
152                 return -EAFNOSUPPORT;
153
154         err = -EEXIST;
155         modemap = afinfo->mode_map;
156         if (likely(modemap[mode->encap] == NULL)) {
157                 modemap[mode->encap] = mode;
158                 err = 0;
159         }
160
161         xfrm_policy_unlock_afinfo(afinfo);
162         return err;
163 }
164 EXPORT_SYMBOL(xfrm_register_mode);
165
166 int xfrm_unregister_mode(struct xfrm_mode *mode, int family)
167 {
168         struct xfrm_policy_afinfo *afinfo;
169         struct xfrm_mode **modemap;
170         int err;
171
172         if (unlikely(mode->encap >= XFRM_MODE_MAX))
173                 return -EINVAL;
174
175         afinfo = xfrm_policy_lock_afinfo(family);
176         if (unlikely(afinfo == NULL))
177                 return -EAFNOSUPPORT;
178
179         err = -ENOENT;
180         modemap = afinfo->mode_map;
181         if (likely(modemap[mode->encap] == mode)) {
182                 modemap[mode->encap] = NULL;
183                 err = 0;
184         }
185
186         xfrm_policy_unlock_afinfo(afinfo);
187         return err;
188 }
189 EXPORT_SYMBOL(xfrm_unregister_mode);
190
191 struct xfrm_mode *xfrm_get_mode(unsigned int encap, int family)
192 {
193         struct xfrm_policy_afinfo *afinfo;
194         struct xfrm_mode *mode;
195         int modload_attempted = 0;
196
197         if (unlikely(encap >= XFRM_MODE_MAX))
198                 return NULL;
199
200 retry:
201         afinfo = xfrm_policy_get_afinfo(family);
202         if (unlikely(afinfo == NULL))
203                 return NULL;
204
205         mode = afinfo->mode_map[encap];
206         if (unlikely(mode && !try_module_get(mode->owner)))
207                 mode = NULL;
208         if (!mode && !modload_attempted) {
209                 xfrm_policy_put_afinfo(afinfo);
210                 request_module("xfrm-mode-%d-%d", family, encap);
211                 modload_attempted = 1;
212                 goto retry;
213         }
214
215         xfrm_policy_put_afinfo(afinfo);
216         return mode;
217 }
218
219 void xfrm_put_mode(struct xfrm_mode *mode)
220 {
221         module_put(mode->owner);
222 }
223
224 static inline unsigned long make_jiffies(long secs)
225 {
226         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
227                 return MAX_SCHEDULE_TIMEOUT-1;
228         else
229                 return secs*HZ;
230 }
231
232 static void xfrm_policy_timer(unsigned long data)
233 {
234         struct xfrm_policy *xp = (struct xfrm_policy*)data;
235         unsigned long now = (unsigned long)xtime.tv_sec;
236         long next = LONG_MAX;
237         int warn = 0;
238         int dir;
239
240         read_lock(&xp->lock);
241
242         if (xp->dead)
243                 goto out;
244
245         dir = xfrm_policy_id2dir(xp->index);
246
247         if (xp->lft.hard_add_expires_seconds) {
248                 long tmo = xp->lft.hard_add_expires_seconds +
249                         xp->curlft.add_time - now;
250                 if (tmo <= 0)
251                         goto expired;
252                 if (tmo < next)
253                         next = tmo;
254         }
255         if (xp->lft.hard_use_expires_seconds) {
256                 long tmo = xp->lft.hard_use_expires_seconds +
257                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
258                 if (tmo <= 0)
259                         goto expired;
260                 if (tmo < next)
261                         next = tmo;
262         }
263         if (xp->lft.soft_add_expires_seconds) {
264                 long tmo = xp->lft.soft_add_expires_seconds +
265                         xp->curlft.add_time - now;
266                 if (tmo <= 0) {
267                         warn = 1;
268                         tmo = XFRM_KM_TIMEOUT;
269                 }
270                 if (tmo < next)
271                         next = tmo;
272         }
273         if (xp->lft.soft_use_expires_seconds) {
274                 long tmo = xp->lft.soft_use_expires_seconds +
275                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
276                 if (tmo <= 0) {
277                         warn = 1;
278                         tmo = XFRM_KM_TIMEOUT;
279                 }
280                 if (tmo < next)
281                         next = tmo;
282         }
283
284         if (warn)
285                 km_policy_expired(xp, dir, 0, 0);
286         if (next != LONG_MAX &&
287             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
288                 xfrm_pol_hold(xp);
289
290 out:
291         read_unlock(&xp->lock);
292         xfrm_pol_put(xp);
293         return;
294
295 expired:
296         read_unlock(&xp->lock);
297         if (!xfrm_policy_delete(xp, dir))
298                 km_policy_expired(xp, dir, 1, 0);
299         xfrm_pol_put(xp);
300 }
301
302
303 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
304  * SPD calls.
305  */
306
307 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp)
308 {
309         struct xfrm_policy *policy;
310
311         policy = kmalloc(sizeof(struct xfrm_policy), gfp);
312
313         if (policy) {
314                 memset(policy, 0, sizeof(struct xfrm_policy));
315                 atomic_set(&policy->refcnt, 1);
316                 rwlock_init(&policy->lock);
317                 init_timer(&policy->timer);
318                 policy->timer.data = (unsigned long)policy;
319                 policy->timer.function = xfrm_policy_timer;
320         }
321         return policy;
322 }
323 EXPORT_SYMBOL(xfrm_policy_alloc);
324
325 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
326
327 void __xfrm_policy_destroy(struct xfrm_policy *policy)
328 {
329         BUG_ON(!policy->dead);
330
331         BUG_ON(policy->bundles);
332
333         if (del_timer(&policy->timer))
334                 BUG();
335
336         security_xfrm_policy_free(policy);
337         kfree(policy);
338 }
339 EXPORT_SYMBOL(__xfrm_policy_destroy);
340
341 static void xfrm_policy_gc_kill(struct xfrm_policy *policy)
342 {
343         struct dst_entry *dst;
344
345         while ((dst = policy->bundles) != NULL) {
346                 policy->bundles = dst->next;
347                 dst_free(dst);
348         }
349
350         if (del_timer(&policy->timer))
351                 atomic_dec(&policy->refcnt);
352
353         if (atomic_read(&policy->refcnt) > 1)
354                 flow_cache_flush();
355
356         xfrm_pol_put(policy);
357 }
358
359 static void xfrm_policy_gc_task(void *data)
360 {
361         struct xfrm_policy *policy;
362         struct list_head *entry, *tmp;
363         struct list_head gc_list = LIST_HEAD_INIT(gc_list);
364
365         spin_lock_bh(&xfrm_policy_gc_lock);
366         list_splice_init(&xfrm_policy_gc_list, &gc_list);
367         spin_unlock_bh(&xfrm_policy_gc_lock);
368
369         list_for_each_safe(entry, tmp, &gc_list) {
370                 policy = list_entry(entry, struct xfrm_policy, list);
371                 xfrm_policy_gc_kill(policy);
372         }
373 }
374
375 /* Rule must be locked. Release descentant resources, announce
376  * entry dead. The rule must be unlinked from lists to the moment.
377  */
378
379 static void xfrm_policy_kill(struct xfrm_policy *policy)
380 {
381         int dead;
382
383         write_lock_bh(&policy->lock);
384         dead = policy->dead;
385         policy->dead = 1;
386         write_unlock_bh(&policy->lock);
387
388         if (unlikely(dead)) {
389                 WARN_ON(1);
390                 return;
391         }
392
393         spin_lock(&xfrm_policy_gc_lock);
394         list_add(&policy->list, &xfrm_policy_gc_list);
395         spin_unlock(&xfrm_policy_gc_lock);
396
397         schedule_work(&xfrm_policy_gc_work);
398 }
399
400 /* Generate new index... KAME seems to generate them ordered by cost
401  * of an absolute inpredictability of ordering of rules. This will not pass. */
402 static u32 xfrm_gen_index(int dir)
403 {
404         u32 idx;
405         struct xfrm_policy *p;
406         static u32 idx_generator;
407
408         for (;;) {
409                 idx = (idx_generator | dir);
410                 idx_generator += 8;
411                 if (idx == 0)
412                         idx = 8;
413                 for (p = xfrm_policy_list[dir]; p; p = p->next) {
414                         if (p->index == idx)
415                                 break;
416                 }
417                 if (!p)
418                         return idx;
419         }
420 }
421
422 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
423 {
424         struct xfrm_policy *pol, **p;
425         struct xfrm_policy *delpol = NULL;
426         struct xfrm_policy **newpos = NULL;
427         struct dst_entry *gc_list;
428
429         write_lock_bh(&xfrm_policy_lock);
430         for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL;) {
431                 if (!delpol && memcmp(&policy->selector, &pol->selector, sizeof(pol->selector)) == 0 &&
432                     xfrm_sec_ctx_match(pol->security, policy->security)) {
433                         if (excl) {
434                                 write_unlock_bh(&xfrm_policy_lock);
435                                 return -EEXIST;
436                         }
437                         *p = pol->next;
438                         delpol = pol;
439                         if (policy->priority > pol->priority)
440                                 continue;
441                 } else if (policy->priority >= pol->priority) {
442                         p = &pol->next;
443                         continue;
444                 }
445                 if (!newpos)
446                         newpos = p;
447                 if (delpol)
448                         break;
449                 p = &pol->next;
450         }
451         if (newpos)
452                 p = newpos;
453         xfrm_pol_hold(policy);
454         policy->next = *p;
455         *p = policy;
456         atomic_inc(&flow_cache_genid);
457         policy->index = delpol ? delpol->index : xfrm_gen_index(dir);
458         policy->curlft.add_time = (unsigned long)xtime.tv_sec;
459         policy->curlft.use_time = 0;
460         if (!mod_timer(&policy->timer, jiffies + HZ))
461                 xfrm_pol_hold(policy);
462         write_unlock_bh(&xfrm_policy_lock);
463
464         if (delpol)
465                 xfrm_policy_kill(delpol);
466
467         read_lock_bh(&xfrm_policy_lock);
468         gc_list = NULL;
469         for (policy = policy->next; policy; policy = policy->next) {
470                 struct dst_entry *dst;
471
472                 write_lock(&policy->lock);
473                 dst = policy->bundles;
474                 if (dst) {
475                         struct dst_entry *tail = dst;
476                         while (tail->next)
477                                 tail = tail->next;
478                         tail->next = gc_list;
479                         gc_list = dst;
480
481                         policy->bundles = NULL;
482                 }
483                 write_unlock(&policy->lock);
484         }
485         read_unlock_bh(&xfrm_policy_lock);
486
487         while (gc_list) {
488                 struct dst_entry *dst = gc_list;
489
490                 gc_list = dst->next;
491                 dst_free(dst);
492         }
493
494         return 0;
495 }
496 EXPORT_SYMBOL(xfrm_policy_insert);
497
498 struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel,
499                                           struct xfrm_sec_ctx *ctx, int delete)
500 {
501         struct xfrm_policy *pol, **p;
502
503         write_lock_bh(&xfrm_policy_lock);
504         for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) {
505                 if ((memcmp(sel, &pol->selector, sizeof(*sel)) == 0) &&
506                     (xfrm_sec_ctx_match(ctx, pol->security))) {
507                         xfrm_pol_hold(pol);
508                         if (delete)
509                                 *p = pol->next;
510                         break;
511                 }
512         }
513         write_unlock_bh(&xfrm_policy_lock);
514
515         if (pol && delete) {
516                 atomic_inc(&flow_cache_genid);
517                 xfrm_policy_kill(pol);
518         }
519         return pol;
520 }
521 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
522
523 struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete)
524 {
525         struct xfrm_policy *pol, **p;
526
527         write_lock_bh(&xfrm_policy_lock);
528         for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) {
529                 if (pol->index == id) {
530                         xfrm_pol_hold(pol);
531                         if (delete)
532                                 *p = pol->next;
533                         break;
534                 }
535         }
536         write_unlock_bh(&xfrm_policy_lock);
537
538         if (pol && delete) {
539                 atomic_inc(&flow_cache_genid);
540                 xfrm_policy_kill(pol);
541         }
542         return pol;
543 }
544 EXPORT_SYMBOL(xfrm_policy_byid);
545
546 void xfrm_policy_flush(void)
547 {
548         struct xfrm_policy *xp;
549         int dir;
550
551         write_lock_bh(&xfrm_policy_lock);
552         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
553                 while ((xp = xfrm_policy_list[dir]) != NULL) {
554                         xfrm_policy_list[dir] = xp->next;
555                         write_unlock_bh(&xfrm_policy_lock);
556
557                         xfrm_policy_kill(xp);
558
559                         write_lock_bh(&xfrm_policy_lock);
560                 }
561         }
562         atomic_inc(&flow_cache_genid);
563         write_unlock_bh(&xfrm_policy_lock);
564 }
565 EXPORT_SYMBOL(xfrm_policy_flush);
566
567 int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*),
568                      void *data)
569 {
570         struct xfrm_policy *xp;
571         int dir;
572         int count = 0;
573         int error = 0;
574
575         read_lock_bh(&xfrm_policy_lock);
576         for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
577                 for (xp = xfrm_policy_list[dir]; xp; xp = xp->next)
578                         count++;
579         }
580
581         if (count == 0) {
582                 error = -ENOENT;
583                 goto out;
584         }
585
586         for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
587                 for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) {
588                         error = func(xp, dir%XFRM_POLICY_MAX, --count, data);
589                         if (error)
590                                 goto out;
591                 }
592         }
593
594 out:
595         read_unlock_bh(&xfrm_policy_lock);
596         return error;
597 }
598 EXPORT_SYMBOL(xfrm_policy_walk);
599
600 /* Find policy to apply to this flow. */
601
602 static void xfrm_policy_lookup(struct flowi *fl, u32 sk_sid, u16 family, u8 dir,
603                                void **objp, atomic_t **obj_refp)
604 {
605         struct xfrm_policy *pol;
606
607         read_lock_bh(&xfrm_policy_lock);
608         for (pol = xfrm_policy_list[dir]; pol; pol = pol->next) {
609                 struct xfrm_selector *sel = &pol->selector;
610                 int match;
611
612                 if (pol->family != family)
613                         continue;
614
615                 match = xfrm_selector_match(sel, fl, family);
616
617                 if (match) {
618                         if (!security_xfrm_policy_lookup(pol, sk_sid, dir)) {
619                                 xfrm_pol_hold(pol);
620                                 break;
621                         }
622                 }
623         }
624         read_unlock_bh(&xfrm_policy_lock);
625         if ((*objp = (void *) pol) != NULL)
626                 *obj_refp = &pol->refcnt;
627 }
628
629 static inline int policy_to_flow_dir(int dir)
630 {
631         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
632             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
633             XFRM_POLICY_FWD == FLOW_DIR_FWD)
634                 return dir;
635         switch (dir) {
636         default:
637         case XFRM_POLICY_IN:
638                 return FLOW_DIR_IN;
639         case XFRM_POLICY_OUT:
640                 return FLOW_DIR_OUT;
641         case XFRM_POLICY_FWD:
642                 return FLOW_DIR_FWD;
643         };
644 }
645
646 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl, u32 sk_sid)
647 {
648         struct xfrm_policy *pol;
649
650         read_lock_bh(&xfrm_policy_lock);
651         if ((pol = sk->sk_policy[dir]) != NULL) {
652                 int match = xfrm_selector_match(&pol->selector, fl,
653                                                 sk->sk_family);
654                 int err = 0;
655
656                 if (match)
657                   err = security_xfrm_policy_lookup(pol, sk_sid, policy_to_flow_dir(dir));
658
659                 if (match && !err)
660                         xfrm_pol_hold(pol);
661                 else
662                         pol = NULL;
663         }
664         read_unlock_bh(&xfrm_policy_lock);
665         return pol;
666 }
667
668 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
669 {
670         pol->next = xfrm_policy_list[dir];
671         xfrm_policy_list[dir] = pol;
672         xfrm_pol_hold(pol);
673 }
674
675 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
676                                                 int dir)
677 {
678         struct xfrm_policy **polp;
679
680         for (polp = &xfrm_policy_list[dir];
681              *polp != NULL; polp = &(*polp)->next) {
682                 if (*polp == pol) {
683                         *polp = pol->next;
684                         return pol;
685                 }
686         }
687         return NULL;
688 }
689
690 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
691 {
692         write_lock_bh(&xfrm_policy_lock);
693         pol = __xfrm_policy_unlink(pol, dir);
694         write_unlock_bh(&xfrm_policy_lock);
695         if (pol) {
696                 if (dir < XFRM_POLICY_MAX)
697                         atomic_inc(&flow_cache_genid);
698                 xfrm_policy_kill(pol);
699                 return 0;
700         }
701         return -ENOENT;
702 }
703 EXPORT_SYMBOL(xfrm_policy_delete);
704
705 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
706 {
707         struct xfrm_policy *old_pol;
708
709         write_lock_bh(&xfrm_policy_lock);
710         old_pol = sk->sk_policy[dir];
711         sk->sk_policy[dir] = pol;
712         if (pol) {
713                 pol->curlft.add_time = (unsigned long)xtime.tv_sec;
714                 pol->index = xfrm_gen_index(XFRM_POLICY_MAX+dir);
715                 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
716         }
717         if (old_pol)
718                 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
719         write_unlock_bh(&xfrm_policy_lock);
720
721         if (old_pol) {
722                 xfrm_policy_kill(old_pol);
723         }
724         return 0;
725 }
726
727 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
728 {
729         struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC);
730
731         if (newp) {
732                 newp->selector = old->selector;
733                 if (security_xfrm_policy_clone(old, newp)) {
734                         kfree(newp);
735                         return NULL;  /* ENOMEM */
736                 }
737                 newp->lft = old->lft;
738                 newp->curlft = old->curlft;
739                 newp->action = old->action;
740                 newp->flags = old->flags;
741                 newp->xfrm_nr = old->xfrm_nr;
742                 newp->index = old->index;
743                 memcpy(newp->xfrm_vec, old->xfrm_vec,
744                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
745                 write_lock_bh(&xfrm_policy_lock);
746                 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
747                 write_unlock_bh(&xfrm_policy_lock);
748                 xfrm_pol_put(newp);
749         }
750         return newp;
751 }
752
753 int __xfrm_sk_clone_policy(struct sock *sk)
754 {
755         struct xfrm_policy *p0 = sk->sk_policy[0],
756                            *p1 = sk->sk_policy[1];
757
758         sk->sk_policy[0] = sk->sk_policy[1] = NULL;
759         if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
760                 return -ENOMEM;
761         if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
762                 return -ENOMEM;
763         return 0;
764 }
765
766 /* Resolve list of templates for the flow, given policy. */
767
768 static int
769 xfrm_tmpl_resolve(struct xfrm_policy *policy, struct flowi *fl,
770                   struct xfrm_state **xfrm,
771                   unsigned short family)
772 {
773         int nx;
774         int i, error;
775         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
776         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
777
778         for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
779                 struct xfrm_state *x;
780                 xfrm_address_t *remote = daddr;
781                 xfrm_address_t *local  = saddr;
782                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
783
784                 if (tmpl->mode) {
785                         remote = &tmpl->id.daddr;
786                         local = &tmpl->saddr;
787                 }
788
789                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
790
791                 if (x && x->km.state == XFRM_STATE_VALID) {
792                         xfrm[nx++] = x;
793                         daddr = remote;
794                         saddr = local;
795                         continue;
796                 }
797                 if (x) {
798                         error = (x->km.state == XFRM_STATE_ERROR ?
799                                  -EINVAL : -EAGAIN);
800                         xfrm_state_put(x);
801                 }
802
803                 if (!tmpl->optional)
804                         goto fail;
805         }
806         return nx;
807
808 fail:
809         for (nx--; nx>=0; nx--)
810                 xfrm_state_put(xfrm[nx]);
811         return error;
812 }
813
814 /* Check that the bundle accepts the flow and its components are
815  * still valid.
816  */
817
818 static struct dst_entry *
819 xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family)
820 {
821         struct dst_entry *x;
822         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
823         if (unlikely(afinfo == NULL))
824                 return ERR_PTR(-EINVAL);
825         x = afinfo->find_bundle(fl, policy);
826         xfrm_policy_put_afinfo(afinfo);
827         return x;
828 }
829
830 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
831  * all the metrics... Shortly, bundle a bundle.
832  */
833
834 static int
835 xfrm_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx,
836                    struct flowi *fl, struct dst_entry **dst_p,
837                    unsigned short family)
838 {
839         int err;
840         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
841         if (unlikely(afinfo == NULL))
842                 return -EINVAL;
843         err = afinfo->bundle_create(policy, xfrm, nx, fl, dst_p);
844         xfrm_policy_put_afinfo(afinfo);
845         return err;
846 }
847
848
849 static int stale_bundle(struct dst_entry *dst);
850
851 /* Main function: finds/creates a bundle for given flow.
852  *
853  * At the moment we eat a raw IP route. Mostly to speed up lookups
854  * on interfaces with disabled IPsec.
855  */
856 int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl,
857                 struct sock *sk, int flags)
858 {
859         struct xfrm_policy *policy;
860         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
861         struct dst_entry *dst, *dst_orig = *dst_p;
862         int nx = 0;
863         int err;
864         u32 genid;
865         u16 family;
866         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
867         u32 sk_sid = security_sk_sid(sk, fl, dir);
868 restart:
869         genid = atomic_read(&flow_cache_genid);
870         policy = NULL;
871         if (sk && sk->sk_policy[1])
872                 policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, sk_sid);
873
874         if (!policy) {
875                 /* To accelerate a bit...  */
876                 if ((dst_orig->flags & DST_NOXFRM) || !xfrm_policy_list[XFRM_POLICY_OUT])
877                         return 0;
878
879                 policy = flow_cache_lookup(fl, sk_sid, dst_orig->ops->family,
880                                            dir, xfrm_policy_lookup);
881         }
882
883         if (!policy)
884                 return 0;
885
886         family = dst_orig->ops->family;
887         policy->curlft.use_time = (unsigned long)xtime.tv_sec;
888
889         switch (policy->action) {
890         case XFRM_POLICY_BLOCK:
891                 /* Prohibit the flow */
892                 err = -EPERM;
893                 goto error;
894
895         case XFRM_POLICY_ALLOW:
896                 if (policy->xfrm_nr == 0) {
897                         /* Flow passes not transformed. */
898                         xfrm_pol_put(policy);
899                         return 0;
900                 }
901
902                 /* Try to find matching bundle.
903                  *
904                  * LATER: help from flow cache. It is optional, this
905                  * is required only for output policy.
906                  */
907                 dst = xfrm_find_bundle(fl, policy, family);
908                 if (IS_ERR(dst)) {
909                         err = PTR_ERR(dst);
910                         goto error;
911                 }
912
913                 if (dst)
914                         break;
915
916                 nx = xfrm_tmpl_resolve(policy, fl, xfrm, family);
917
918                 if (unlikely(nx<0)) {
919                         err = nx;
920                         if (err == -EAGAIN && flags) {
921                                 DECLARE_WAITQUEUE(wait, current);
922
923                                 add_wait_queue(&km_waitq, &wait);
924                                 set_current_state(TASK_INTERRUPTIBLE);
925                                 schedule();
926                                 set_current_state(TASK_RUNNING);
927                                 remove_wait_queue(&km_waitq, &wait);
928
929                                 nx = xfrm_tmpl_resolve(policy, fl, xfrm, family);
930
931                                 if (nx == -EAGAIN && signal_pending(current)) {
932                                         err = -ERESTART;
933                                         goto error;
934                                 }
935                                 if (nx == -EAGAIN ||
936                                     genid != atomic_read(&flow_cache_genid)) {
937                                         xfrm_pol_put(policy);
938                                         goto restart;
939                                 }
940                                 err = nx;
941                         }
942                         if (err < 0)
943                                 goto error;
944                 }
945                 if (nx == 0) {
946                         /* Flow passes not transformed. */
947                         xfrm_pol_put(policy);
948                         return 0;
949                 }
950
951                 dst = dst_orig;
952                 err = xfrm_bundle_create(policy, xfrm, nx, fl, &dst, family);
953
954                 if (unlikely(err)) {
955                         int i;
956                         for (i=0; i<nx; i++)
957                                 xfrm_state_put(xfrm[i]);
958                         goto error;
959                 }
960
961                 write_lock_bh(&policy->lock);
962                 if (unlikely(policy->dead || stale_bundle(dst))) {
963                         /* Wow! While we worked on resolving, this
964                          * policy has gone. Retry. It is not paranoia,
965                          * we just cannot enlist new bundle to dead object.
966                          * We can't enlist stable bundles either.
967                          */
968                         write_unlock_bh(&policy->lock);
969                         if (dst)
970                                 dst_free(dst);
971
972                         err = -EHOSTUNREACH;
973                         goto error;
974                 }
975                 dst->next = policy->bundles;
976                 policy->bundles = dst;
977                 dst_hold(dst);
978                 write_unlock_bh(&policy->lock);
979         }
980         *dst_p = dst;
981         dst_release(dst_orig);
982         xfrm_pol_put(policy);
983         return 0;
984
985 error:
986         dst_release(dst_orig);
987         xfrm_pol_put(policy);
988         *dst_p = NULL;
989         return err;
990 }
991 EXPORT_SYMBOL(xfrm_lookup);
992
993 /* When skb is transformed back to its "native" form, we have to
994  * check policy restrictions. At the moment we make this in maximally
995  * stupid way. Shame on me. :-) Of course, connected sockets must
996  * have policy cached at them.
997  */
998
999 static inline int
1000 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x, 
1001               unsigned short family)
1002 {
1003         if (xfrm_state_kern(x))
1004                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, family);
1005         return  x->id.proto == tmpl->id.proto &&
1006                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1007                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1008                 x->props.mode == tmpl->mode &&
1009                 (tmpl->aalgos & (1<<x->props.aalgo)) &&
1010                 !(x->props.mode && xfrm_state_addr_cmp(tmpl, x, family));
1011 }
1012
1013 static inline int
1014 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1015                unsigned short family)
1016 {
1017         int idx = start;
1018
1019         if (tmpl->optional) {
1020                 if (!tmpl->mode)
1021                         return start;
1022         } else
1023                 start = -1;
1024         for (; idx < sp->len; idx++) {
1025                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1026                         return ++idx;
1027                 if (sp->xvec[idx]->props.mode)
1028                         break;
1029         }
1030         return start;
1031 }
1032
1033 int
1034 xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family)
1035 {
1036         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1037
1038         if (unlikely(afinfo == NULL))
1039                 return -EAFNOSUPPORT;
1040
1041         afinfo->decode_session(skb, fl);
1042         xfrm_policy_put_afinfo(afinfo);
1043         return 0;
1044 }
1045 EXPORT_SYMBOL(xfrm_decode_session);
1046
1047 static inline int secpath_has_tunnel(struct sec_path *sp, int k)
1048 {
1049         for (; k < sp->len; k++) {
1050                 if (sp->xvec[k]->props.mode)
1051                         return 1;
1052         }
1053
1054         return 0;
1055 }
1056
1057 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 
1058                         unsigned short family)
1059 {
1060         struct xfrm_policy *pol;
1061         struct flowi fl;
1062         u8 fl_dir = policy_to_flow_dir(dir);
1063         u32 sk_sid;
1064
1065         if (xfrm_decode_session(skb, &fl, family) < 0)
1066                 return 0;
1067         nf_nat_decode_session(skb, &fl, family);
1068
1069         sk_sid = security_sk_sid(sk, &fl, fl_dir);
1070
1071         /* First, check used SA against their selectors. */
1072         if (skb->sp) {
1073                 int i;
1074
1075                 for (i=skb->sp->len-1; i>=0; i--) {
1076                         struct xfrm_state *x = skb->sp->xvec[i];
1077                         if (!xfrm_selector_match(&x->sel, &fl, family))
1078                                 return 0;
1079                 }
1080         }
1081
1082         pol = NULL;
1083         if (sk && sk->sk_policy[dir])
1084                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, sk_sid);
1085
1086         if (!pol)
1087                 pol = flow_cache_lookup(&fl, sk_sid, family, fl_dir,
1088                                         xfrm_policy_lookup);
1089
1090         if (!pol)
1091                 return !skb->sp || !secpath_has_tunnel(skb->sp, 0);
1092
1093         pol->curlft.use_time = (unsigned long)xtime.tv_sec;
1094
1095         if (pol->action == XFRM_POLICY_ALLOW) {
1096                 struct sec_path *sp;
1097                 static struct sec_path dummy;
1098                 int i, k;
1099
1100                 if ((sp = skb->sp) == NULL)
1101                         sp = &dummy;
1102
1103                 /* For each tunnel xfrm, find the first matching tmpl.
1104                  * For each tmpl before that, find corresponding xfrm.
1105                  * Order is _important_. Later we will implement
1106                  * some barriers, but at the moment barriers
1107                  * are implied between each two transformations.
1108                  */
1109                 for (i = pol->xfrm_nr-1, k = 0; i >= 0; i--) {
1110                         k = xfrm_policy_ok(pol->xfrm_vec+i, sp, k, family);
1111                         if (k < 0)
1112                                 goto reject;
1113                 }
1114
1115                 if (secpath_has_tunnel(sp, k))
1116                         goto reject;
1117
1118                 xfrm_pol_put(pol);
1119                 return 1;
1120         }
1121
1122 reject:
1123         xfrm_pol_put(pol);
1124         return 0;
1125 }
1126 EXPORT_SYMBOL(__xfrm_policy_check);
1127
1128 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1129 {
1130         struct flowi fl;
1131
1132         if (xfrm_decode_session(skb, &fl, family) < 0)
1133                 return 0;
1134
1135         return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0;
1136 }
1137 EXPORT_SYMBOL(__xfrm_route_forward);
1138
1139 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
1140 {
1141         /* If it is marked obsolete, which is how we even get here,
1142          * then we have purged it from the policy bundle list and we
1143          * did that for a good reason.
1144          */
1145         return NULL;
1146 }
1147
1148 static int stale_bundle(struct dst_entry *dst)
1149 {
1150         return !xfrm_bundle_ok((struct xfrm_dst *)dst, NULL, AF_UNSPEC);
1151 }
1152
1153 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
1154 {
1155         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
1156                 dst->dev = &loopback_dev;
1157                 dev_hold(&loopback_dev);
1158                 dev_put(dev);
1159         }
1160 }
1161 EXPORT_SYMBOL(xfrm_dst_ifdown);
1162
1163 static void xfrm_link_failure(struct sk_buff *skb)
1164 {
1165         /* Impossible. Such dst must be popped before reaches point of failure. */
1166         return;
1167 }
1168
1169 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
1170 {
1171         if (dst) {
1172                 if (dst->obsolete) {
1173                         dst_release(dst);
1174                         dst = NULL;
1175                 }
1176         }
1177         return dst;
1178 }
1179
1180 static void xfrm_prune_bundles(int (*func)(struct dst_entry *))
1181 {
1182         int i;
1183         struct xfrm_policy *pol;
1184         struct dst_entry *dst, **dstp, *gc_list = NULL;
1185
1186         read_lock_bh(&xfrm_policy_lock);
1187         for (i=0; i<2*XFRM_POLICY_MAX; i++) {
1188                 for (pol = xfrm_policy_list[i]; pol; pol = pol->next) {
1189                         write_lock(&pol->lock);
1190                         dstp = &pol->bundles;
1191                         while ((dst=*dstp) != NULL) {
1192                                 if (func(dst)) {
1193                                         *dstp = dst->next;
1194                                         dst->next = gc_list;
1195                                         gc_list = dst;
1196                                 } else {
1197                                         dstp = &dst->next;
1198                                 }
1199                         }
1200                         write_unlock(&pol->lock);
1201                 }
1202         }
1203         read_unlock_bh(&xfrm_policy_lock);
1204
1205         while (gc_list) {
1206                 dst = gc_list;
1207                 gc_list = dst->next;
1208                 dst_free(dst);
1209         }
1210 }
1211
1212 static int unused_bundle(struct dst_entry *dst)
1213 {
1214         return !atomic_read(&dst->__refcnt);
1215 }
1216
1217 static void __xfrm_garbage_collect(void)
1218 {
1219         xfrm_prune_bundles(unused_bundle);
1220 }
1221
1222 int xfrm_flush_bundles(void)
1223 {
1224         xfrm_prune_bundles(stale_bundle);
1225         return 0;
1226 }
1227
1228 static int always_true(struct dst_entry *dst)
1229 {
1230         return 1;
1231 }
1232
1233 void xfrm_flush_all_bundles(void)
1234 {
1235         xfrm_prune_bundles(always_true);
1236 }
1237
1238 void xfrm_init_pmtu(struct dst_entry *dst)
1239 {
1240         do {
1241                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1242                 u32 pmtu, route_mtu_cached;
1243
1244                 pmtu = dst_mtu(dst->child);
1245                 xdst->child_mtu_cached = pmtu;
1246
1247                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
1248
1249                 route_mtu_cached = dst_mtu(xdst->route);
1250                 xdst->route_mtu_cached = route_mtu_cached;
1251
1252                 if (pmtu > route_mtu_cached)
1253                         pmtu = route_mtu_cached;
1254
1255                 dst->metrics[RTAX_MTU-1] = pmtu;
1256         } while ((dst = dst->next));
1257 }
1258
1259 EXPORT_SYMBOL(xfrm_init_pmtu);
1260
1261 /* Check that the bundle accepts the flow and its components are
1262  * still valid.
1263  */
1264
1265 int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family)
1266 {
1267         struct dst_entry *dst = &first->u.dst;
1268         struct xfrm_dst *last;
1269         u32 mtu;
1270
1271         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
1272             (dst->dev && !netif_running(dst->dev)))
1273                 return 0;
1274
1275         last = NULL;
1276
1277         do {
1278                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1279
1280                 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
1281                         return 0;
1282                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
1283                         return 0;
1284
1285                 mtu = dst_mtu(dst->child);
1286                 if (xdst->child_mtu_cached != mtu) {
1287                         last = xdst;
1288                         xdst->child_mtu_cached = mtu;
1289                 }
1290
1291                 if (!dst_check(xdst->route, xdst->route_cookie))
1292                         return 0;
1293                 mtu = dst_mtu(xdst->route);
1294                 if (xdst->route_mtu_cached != mtu) {
1295                         last = xdst;
1296                         xdst->route_mtu_cached = mtu;
1297                 }
1298
1299                 dst = dst->child;
1300         } while (dst->xfrm);
1301
1302         if (likely(!last))
1303                 return 1;
1304
1305         mtu = last->child_mtu_cached;
1306         for (;;) {
1307                 dst = &last->u.dst;
1308
1309                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
1310                 if (mtu > last->route_mtu_cached)
1311                         mtu = last->route_mtu_cached;
1312                 dst->metrics[RTAX_MTU-1] = mtu;
1313
1314                 if (last == first)
1315                         break;
1316
1317                 last = last->u.next;
1318                 last->child_mtu_cached = mtu;
1319         }
1320
1321         return 1;
1322 }
1323
1324 EXPORT_SYMBOL(xfrm_bundle_ok);
1325
1326 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
1327 {
1328         int err = 0;
1329         if (unlikely(afinfo == NULL))
1330                 return -EINVAL;
1331         if (unlikely(afinfo->family >= NPROTO))
1332                 return -EAFNOSUPPORT;
1333         write_lock_bh(&xfrm_policy_afinfo_lock);
1334         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
1335                 err = -ENOBUFS;
1336         else {
1337                 struct dst_ops *dst_ops = afinfo->dst_ops;
1338                 if (likely(dst_ops->kmem_cachep == NULL))
1339                         dst_ops->kmem_cachep = xfrm_dst_cache;
1340                 if (likely(dst_ops->check == NULL))
1341                         dst_ops->check = xfrm_dst_check;
1342                 if (likely(dst_ops->negative_advice == NULL))
1343                         dst_ops->negative_advice = xfrm_negative_advice;
1344                 if (likely(dst_ops->link_failure == NULL))
1345                         dst_ops->link_failure = xfrm_link_failure;
1346                 if (likely(afinfo->garbage_collect == NULL))
1347                         afinfo->garbage_collect = __xfrm_garbage_collect;
1348                 xfrm_policy_afinfo[afinfo->family] = afinfo;
1349         }
1350         write_unlock_bh(&xfrm_policy_afinfo_lock);
1351         return err;
1352 }
1353 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
1354
1355 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
1356 {
1357         int err = 0;
1358         if (unlikely(afinfo == NULL))
1359                 return -EINVAL;
1360         if (unlikely(afinfo->family >= NPROTO))
1361                 return -EAFNOSUPPORT;
1362         write_lock_bh(&xfrm_policy_afinfo_lock);
1363         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
1364                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
1365                         err = -EINVAL;
1366                 else {
1367                         struct dst_ops *dst_ops = afinfo->dst_ops;
1368                         xfrm_policy_afinfo[afinfo->family] = NULL;
1369                         dst_ops->kmem_cachep = NULL;
1370                         dst_ops->check = NULL;
1371                         dst_ops->negative_advice = NULL;
1372                         dst_ops->link_failure = NULL;
1373                         afinfo->garbage_collect = NULL;
1374                 }
1375         }
1376         write_unlock_bh(&xfrm_policy_afinfo_lock);
1377         return err;
1378 }
1379 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
1380
1381 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
1382 {
1383         struct xfrm_policy_afinfo *afinfo;
1384         if (unlikely(family >= NPROTO))
1385                 return NULL;
1386         read_lock(&xfrm_policy_afinfo_lock);
1387         afinfo = xfrm_policy_afinfo[family];
1388         if (unlikely(!afinfo))
1389                 read_unlock(&xfrm_policy_afinfo_lock);
1390         return afinfo;
1391 }
1392
1393 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
1394 {
1395         read_unlock(&xfrm_policy_afinfo_lock);
1396 }
1397
1398 static struct xfrm_policy_afinfo *xfrm_policy_lock_afinfo(unsigned int family)
1399 {
1400         struct xfrm_policy_afinfo *afinfo;
1401         if (unlikely(family >= NPROTO))
1402                 return NULL;
1403         write_lock_bh(&xfrm_policy_afinfo_lock);
1404         afinfo = xfrm_policy_afinfo[family];
1405         if (unlikely(!afinfo))
1406                 write_unlock_bh(&xfrm_policy_afinfo_lock);
1407         return afinfo;
1408 }
1409
1410 static void xfrm_policy_unlock_afinfo(struct xfrm_policy_afinfo *afinfo)
1411 {
1412         write_unlock_bh(&xfrm_policy_afinfo_lock);
1413 }
1414
1415 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
1416 {
1417         switch (event) {
1418         case NETDEV_DOWN:
1419                 xfrm_flush_bundles();
1420         }
1421         return NOTIFY_DONE;
1422 }
1423
1424 static struct notifier_block xfrm_dev_notifier = {
1425         xfrm_dev_event,
1426         NULL,
1427         0
1428 };
1429
1430 static void __init xfrm_policy_init(void)
1431 {
1432         xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
1433                                            sizeof(struct xfrm_dst),
1434                                            0, SLAB_HWCACHE_ALIGN,
1435                                            NULL, NULL);
1436         if (!xfrm_dst_cache)
1437                 panic("XFRM: failed to allocate xfrm_dst_cache\n");
1438
1439         INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task, NULL);
1440         register_netdevice_notifier(&xfrm_dev_notifier);
1441 }
1442
1443 void __init xfrm_init(void)
1444 {
1445         xfrm_state_init();
1446         xfrm_policy_init();
1447         xfrm_input_init();
1448 }
1449