xfrm: fix policy unreferencing on larval drop
[safe/jmp/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/err.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 <linux/cache.h>
27 #include <linux/audit.h>
28 #include <net/dst.h>
29 #include <net/xfrm.h>
30 #include <net/ip.h>
31 #ifdef CONFIG_XFRM_STATISTICS
32 #include <net/snmp.h>
33 #endif
34
35 #include "xfrm_hash.h"
36
37 DEFINE_MUTEX(xfrm_cfg_mutex);
38 EXPORT_SYMBOL(xfrm_cfg_mutex);
39
40 static DEFINE_SPINLOCK(xfrm_policy_sk_bundle_lock);
41 static struct dst_entry *xfrm_policy_sk_bundles;
42 static DEFINE_RWLOCK(xfrm_policy_lock);
43
44 static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
45 static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
46
47 static struct kmem_cache *xfrm_dst_cache __read_mostly;
48
49 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
50 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
51 static void xfrm_init_pmtu(struct dst_entry *dst);
52 static int stale_bundle(struct dst_entry *dst);
53
54 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
55                                                 int dir);
56
57 static inline int
58 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
59 {
60         return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
61                 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
62                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
63                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
64                 (fl->proto == sel->proto || !sel->proto) &&
65                 (fl->oif == sel->ifindex || !sel->ifindex);
66 }
67
68 static inline int
69 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
70 {
71         return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
72                 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
73                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
74                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
75                 (fl->proto == sel->proto || !sel->proto) &&
76                 (fl->oif == sel->ifindex || !sel->ifindex);
77 }
78
79 int xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
80                     unsigned short family)
81 {
82         switch (family) {
83         case AF_INET:
84                 return __xfrm4_selector_match(sel, fl);
85         case AF_INET6:
86                 return __xfrm6_selector_match(sel, fl);
87         }
88         return 0;
89 }
90
91 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
92                                                   xfrm_address_t *saddr,
93                                                   xfrm_address_t *daddr,
94                                                   int family)
95 {
96         struct xfrm_policy_afinfo *afinfo;
97         struct dst_entry *dst;
98
99         afinfo = xfrm_policy_get_afinfo(family);
100         if (unlikely(afinfo == NULL))
101                 return ERR_PTR(-EAFNOSUPPORT);
102
103         dst = afinfo->dst_lookup(net, tos, saddr, daddr);
104
105         xfrm_policy_put_afinfo(afinfo);
106
107         return dst;
108 }
109
110 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
111                                                 xfrm_address_t *prev_saddr,
112                                                 xfrm_address_t *prev_daddr,
113                                                 int family)
114 {
115         struct net *net = xs_net(x);
116         xfrm_address_t *saddr = &x->props.saddr;
117         xfrm_address_t *daddr = &x->id.daddr;
118         struct dst_entry *dst;
119
120         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
121                 saddr = x->coaddr;
122                 daddr = prev_daddr;
123         }
124         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
125                 saddr = prev_saddr;
126                 daddr = x->coaddr;
127         }
128
129         dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
130
131         if (!IS_ERR(dst)) {
132                 if (prev_saddr != saddr)
133                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
134                 if (prev_daddr != daddr)
135                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
136         }
137
138         return dst;
139 }
140
141 static inline unsigned long make_jiffies(long secs)
142 {
143         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
144                 return MAX_SCHEDULE_TIMEOUT-1;
145         else
146                 return secs*HZ;
147 }
148
149 static void xfrm_policy_timer(unsigned long data)
150 {
151         struct xfrm_policy *xp = (struct xfrm_policy*)data;
152         unsigned long now = get_seconds();
153         long next = LONG_MAX;
154         int warn = 0;
155         int dir;
156
157         read_lock(&xp->lock);
158
159         if (unlikely(xp->walk.dead))
160                 goto out;
161
162         dir = xfrm_policy_id2dir(xp->index);
163
164         if (xp->lft.hard_add_expires_seconds) {
165                 long tmo = xp->lft.hard_add_expires_seconds +
166                         xp->curlft.add_time - now;
167                 if (tmo <= 0)
168                         goto expired;
169                 if (tmo < next)
170                         next = tmo;
171         }
172         if (xp->lft.hard_use_expires_seconds) {
173                 long tmo = xp->lft.hard_use_expires_seconds +
174                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
175                 if (tmo <= 0)
176                         goto expired;
177                 if (tmo < next)
178                         next = tmo;
179         }
180         if (xp->lft.soft_add_expires_seconds) {
181                 long tmo = xp->lft.soft_add_expires_seconds +
182                         xp->curlft.add_time - now;
183                 if (tmo <= 0) {
184                         warn = 1;
185                         tmo = XFRM_KM_TIMEOUT;
186                 }
187                 if (tmo < next)
188                         next = tmo;
189         }
190         if (xp->lft.soft_use_expires_seconds) {
191                 long tmo = xp->lft.soft_use_expires_seconds +
192                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
193                 if (tmo <= 0) {
194                         warn = 1;
195                         tmo = XFRM_KM_TIMEOUT;
196                 }
197                 if (tmo < next)
198                         next = tmo;
199         }
200
201         if (warn)
202                 km_policy_expired(xp, dir, 0, 0);
203         if (next != LONG_MAX &&
204             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
205                 xfrm_pol_hold(xp);
206
207 out:
208         read_unlock(&xp->lock);
209         xfrm_pol_put(xp);
210         return;
211
212 expired:
213         read_unlock(&xp->lock);
214         if (!xfrm_policy_delete(xp, dir))
215                 km_policy_expired(xp, dir, 1, 0);
216         xfrm_pol_put(xp);
217 }
218
219 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
220 {
221         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
222
223         if (unlikely(pol->walk.dead))
224                 flo = NULL;
225         else
226                 xfrm_pol_hold(pol);
227
228         return flo;
229 }
230
231 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
232 {
233         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
234
235         return !pol->walk.dead;
236 }
237
238 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
239 {
240         xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
241 }
242
243 static const struct flow_cache_ops xfrm_policy_fc_ops = {
244         .get = xfrm_policy_flo_get,
245         .check = xfrm_policy_flo_check,
246         .delete = xfrm_policy_flo_delete,
247 };
248
249 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
250  * SPD calls.
251  */
252
253 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
254 {
255         struct xfrm_policy *policy;
256
257         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
258
259         if (policy) {
260                 write_pnet(&policy->xp_net, net);
261                 INIT_LIST_HEAD(&policy->walk.all);
262                 INIT_HLIST_NODE(&policy->bydst);
263                 INIT_HLIST_NODE(&policy->byidx);
264                 rwlock_init(&policy->lock);
265                 atomic_set(&policy->refcnt, 1);
266                 setup_timer(&policy->timer, xfrm_policy_timer,
267                                 (unsigned long)policy);
268                 policy->flo.ops = &xfrm_policy_fc_ops;
269         }
270         return policy;
271 }
272 EXPORT_SYMBOL(xfrm_policy_alloc);
273
274 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
275
276 void xfrm_policy_destroy(struct xfrm_policy *policy)
277 {
278         BUG_ON(!policy->walk.dead);
279
280         if (del_timer(&policy->timer))
281                 BUG();
282
283         security_xfrm_policy_free(policy->security);
284         kfree(policy);
285 }
286 EXPORT_SYMBOL(xfrm_policy_destroy);
287
288 /* Rule must be locked. Release descentant resources, announce
289  * entry dead. The rule must be unlinked from lists to the moment.
290  */
291
292 static void xfrm_policy_kill(struct xfrm_policy *policy)
293 {
294         policy->walk.dead = 1;
295
296         atomic_inc(&policy->genid);
297
298         if (del_timer(&policy->timer))
299                 xfrm_pol_put(policy);
300
301         xfrm_pol_put(policy);
302 }
303
304 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
305
306 static inline unsigned int idx_hash(struct net *net, u32 index)
307 {
308         return __idx_hash(index, net->xfrm.policy_idx_hmask);
309 }
310
311 static struct hlist_head *policy_hash_bysel(struct net *net, struct xfrm_selector *sel, unsigned short family, int dir)
312 {
313         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
314         unsigned int hash = __sel_hash(sel, family, hmask);
315
316         return (hash == hmask + 1 ?
317                 &net->xfrm.policy_inexact[dir] :
318                 net->xfrm.policy_bydst[dir].table + hash);
319 }
320
321 static struct hlist_head *policy_hash_direct(struct net *net, xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, int dir)
322 {
323         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
324         unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
325
326         return net->xfrm.policy_bydst[dir].table + hash;
327 }
328
329 static void xfrm_dst_hash_transfer(struct hlist_head *list,
330                                    struct hlist_head *ndsttable,
331                                    unsigned int nhashmask)
332 {
333         struct hlist_node *entry, *tmp, *entry0 = NULL;
334         struct xfrm_policy *pol;
335         unsigned int h0 = 0;
336
337 redo:
338         hlist_for_each_entry_safe(pol, entry, tmp, list, bydst) {
339                 unsigned int h;
340
341                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
342                                 pol->family, nhashmask);
343                 if (!entry0) {
344                         hlist_del(entry);
345                         hlist_add_head(&pol->bydst, ndsttable+h);
346                         h0 = h;
347                 } else {
348                         if (h != h0)
349                                 continue;
350                         hlist_del(entry);
351                         hlist_add_after(entry0, &pol->bydst);
352                 }
353                 entry0 = entry;
354         }
355         if (!hlist_empty(list)) {
356                 entry0 = NULL;
357                 goto redo;
358         }
359 }
360
361 static void xfrm_idx_hash_transfer(struct hlist_head *list,
362                                    struct hlist_head *nidxtable,
363                                    unsigned int nhashmask)
364 {
365         struct hlist_node *entry, *tmp;
366         struct xfrm_policy *pol;
367
368         hlist_for_each_entry_safe(pol, entry, tmp, list, byidx) {
369                 unsigned int h;
370
371                 h = __idx_hash(pol->index, nhashmask);
372                 hlist_add_head(&pol->byidx, nidxtable+h);
373         }
374 }
375
376 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
377 {
378         return ((old_hmask + 1) << 1) - 1;
379 }
380
381 static void xfrm_bydst_resize(struct net *net, int dir)
382 {
383         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
384         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
385         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
386         struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
387         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
388         int i;
389
390         if (!ndst)
391                 return;
392
393         write_lock_bh(&xfrm_policy_lock);
394
395         for (i = hmask; i >= 0; i--)
396                 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
397
398         net->xfrm.policy_bydst[dir].table = ndst;
399         net->xfrm.policy_bydst[dir].hmask = nhashmask;
400
401         write_unlock_bh(&xfrm_policy_lock);
402
403         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
404 }
405
406 static void xfrm_byidx_resize(struct net *net, int total)
407 {
408         unsigned int hmask = net->xfrm.policy_idx_hmask;
409         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
410         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
411         struct hlist_head *oidx = net->xfrm.policy_byidx;
412         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
413         int i;
414
415         if (!nidx)
416                 return;
417
418         write_lock_bh(&xfrm_policy_lock);
419
420         for (i = hmask; i >= 0; i--)
421                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
422
423         net->xfrm.policy_byidx = nidx;
424         net->xfrm.policy_idx_hmask = nhashmask;
425
426         write_unlock_bh(&xfrm_policy_lock);
427
428         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
429 }
430
431 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
432 {
433         unsigned int cnt = net->xfrm.policy_count[dir];
434         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
435
436         if (total)
437                 *total += cnt;
438
439         if ((hmask + 1) < xfrm_policy_hashmax &&
440             cnt > hmask)
441                 return 1;
442
443         return 0;
444 }
445
446 static inline int xfrm_byidx_should_resize(struct net *net, int total)
447 {
448         unsigned int hmask = net->xfrm.policy_idx_hmask;
449
450         if ((hmask + 1) < xfrm_policy_hashmax &&
451             total > hmask)
452                 return 1;
453
454         return 0;
455 }
456
457 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
458 {
459         read_lock_bh(&xfrm_policy_lock);
460         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
461         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
462         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
463         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
464         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
465         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
466         si->spdhcnt = net->xfrm.policy_idx_hmask;
467         si->spdhmcnt = xfrm_policy_hashmax;
468         read_unlock_bh(&xfrm_policy_lock);
469 }
470 EXPORT_SYMBOL(xfrm_spd_getinfo);
471
472 static DEFINE_MUTEX(hash_resize_mutex);
473 static void xfrm_hash_resize(struct work_struct *work)
474 {
475         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
476         int dir, total;
477
478         mutex_lock(&hash_resize_mutex);
479
480         total = 0;
481         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
482                 if (xfrm_bydst_should_resize(net, dir, &total))
483                         xfrm_bydst_resize(net, dir);
484         }
485         if (xfrm_byidx_should_resize(net, total))
486                 xfrm_byidx_resize(net, total);
487
488         mutex_unlock(&hash_resize_mutex);
489 }
490
491 /* Generate new index... KAME seems to generate them ordered by cost
492  * of an absolute inpredictability of ordering of rules. This will not pass. */
493 static u32 xfrm_gen_index(struct net *net, int dir)
494 {
495         static u32 idx_generator;
496
497         for (;;) {
498                 struct hlist_node *entry;
499                 struct hlist_head *list;
500                 struct xfrm_policy *p;
501                 u32 idx;
502                 int found;
503
504                 idx = (idx_generator | dir);
505                 idx_generator += 8;
506                 if (idx == 0)
507                         idx = 8;
508                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
509                 found = 0;
510                 hlist_for_each_entry(p, entry, list, byidx) {
511                         if (p->index == idx) {
512                                 found = 1;
513                                 break;
514                         }
515                 }
516                 if (!found)
517                         return idx;
518         }
519 }
520
521 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
522 {
523         u32 *p1 = (u32 *) s1;
524         u32 *p2 = (u32 *) s2;
525         int len = sizeof(struct xfrm_selector) / sizeof(u32);
526         int i;
527
528         for (i = 0; i < len; i++) {
529                 if (p1[i] != p2[i])
530                         return 1;
531         }
532
533         return 0;
534 }
535
536 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
537 {
538         struct net *net = xp_net(policy);
539         struct xfrm_policy *pol;
540         struct xfrm_policy *delpol;
541         struct hlist_head *chain;
542         struct hlist_node *entry, *newpos;
543         u32 mark = policy->mark.v & policy->mark.m;
544
545         write_lock_bh(&xfrm_policy_lock);
546         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
547         delpol = NULL;
548         newpos = NULL;
549         hlist_for_each_entry(pol, entry, chain, bydst) {
550                 if (pol->type == policy->type &&
551                     !selector_cmp(&pol->selector, &policy->selector) &&
552                     (mark & pol->mark.m) == pol->mark.v &&
553                     xfrm_sec_ctx_match(pol->security, policy->security) &&
554                     !WARN_ON(delpol)) {
555                         if (excl) {
556                                 write_unlock_bh(&xfrm_policy_lock);
557                                 return -EEXIST;
558                         }
559                         delpol = pol;
560                         if (policy->priority > pol->priority)
561                                 continue;
562                 } else if (policy->priority >= pol->priority) {
563                         newpos = &pol->bydst;
564                         continue;
565                 }
566                 if (delpol)
567                         break;
568         }
569         if (newpos)
570                 hlist_add_after(newpos, &policy->bydst);
571         else
572                 hlist_add_head(&policy->bydst, chain);
573         xfrm_pol_hold(policy);
574         net->xfrm.policy_count[dir]++;
575         atomic_inc(&flow_cache_genid);
576         if (delpol)
577                 __xfrm_policy_unlink(delpol, dir);
578         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir);
579         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
580         policy->curlft.add_time = get_seconds();
581         policy->curlft.use_time = 0;
582         if (!mod_timer(&policy->timer, jiffies + HZ))
583                 xfrm_pol_hold(policy);
584         list_add(&policy->walk.all, &net->xfrm.policy_all);
585         write_unlock_bh(&xfrm_policy_lock);
586
587         if (delpol)
588                 xfrm_policy_kill(delpol);
589         else if (xfrm_bydst_should_resize(net, dir, NULL))
590                 schedule_work(&net->xfrm.policy_hash_work);
591
592         return 0;
593 }
594 EXPORT_SYMBOL(xfrm_policy_insert);
595
596 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
597                                           int dir, struct xfrm_selector *sel,
598                                           struct xfrm_sec_ctx *ctx, int delete,
599                                           int *err)
600 {
601         struct xfrm_policy *pol, *ret;
602         struct hlist_head *chain;
603         struct hlist_node *entry;
604
605         *err = 0;
606         write_lock_bh(&xfrm_policy_lock);
607         chain = policy_hash_bysel(net, sel, sel->family, dir);
608         ret = NULL;
609         hlist_for_each_entry(pol, entry, chain, bydst) {
610                 if (pol->type == type &&
611                     (mark & pol->mark.m) == pol->mark.v &&
612                     !selector_cmp(sel, &pol->selector) &&
613                     xfrm_sec_ctx_match(ctx, pol->security)) {
614                         xfrm_pol_hold(pol);
615                         if (delete) {
616                                 *err = security_xfrm_policy_delete(
617                                                                 pol->security);
618                                 if (*err) {
619                                         write_unlock_bh(&xfrm_policy_lock);
620                                         return pol;
621                                 }
622                                 __xfrm_policy_unlink(pol, dir);
623                         }
624                         ret = pol;
625                         break;
626                 }
627         }
628         write_unlock_bh(&xfrm_policy_lock);
629
630         if (ret && delete)
631                 xfrm_policy_kill(ret);
632         return ret;
633 }
634 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
635
636 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
637                                      int dir, u32 id, int delete, int *err)
638 {
639         struct xfrm_policy *pol, *ret;
640         struct hlist_head *chain;
641         struct hlist_node *entry;
642
643         *err = -ENOENT;
644         if (xfrm_policy_id2dir(id) != dir)
645                 return NULL;
646
647         *err = 0;
648         write_lock_bh(&xfrm_policy_lock);
649         chain = net->xfrm.policy_byidx + idx_hash(net, id);
650         ret = NULL;
651         hlist_for_each_entry(pol, entry, chain, byidx) {
652                 if (pol->type == type && pol->index == id &&
653                     (mark & pol->mark.m) == pol->mark.v) {
654                         xfrm_pol_hold(pol);
655                         if (delete) {
656                                 *err = security_xfrm_policy_delete(
657                                                                 pol->security);
658                                 if (*err) {
659                                         write_unlock_bh(&xfrm_policy_lock);
660                                         return pol;
661                                 }
662                                 __xfrm_policy_unlink(pol, dir);
663                         }
664                         ret = pol;
665                         break;
666                 }
667         }
668         write_unlock_bh(&xfrm_policy_lock);
669
670         if (ret && delete)
671                 xfrm_policy_kill(ret);
672         return ret;
673 }
674 EXPORT_SYMBOL(xfrm_policy_byid);
675
676 #ifdef CONFIG_SECURITY_NETWORK_XFRM
677 static inline int
678 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
679 {
680         int dir, err = 0;
681
682         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
683                 struct xfrm_policy *pol;
684                 struct hlist_node *entry;
685                 int i;
686
687                 hlist_for_each_entry(pol, entry,
688                                      &net->xfrm.policy_inexact[dir], bydst) {
689                         if (pol->type != type)
690                                 continue;
691                         err = security_xfrm_policy_delete(pol->security);
692                         if (err) {
693                                 xfrm_audit_policy_delete(pol, 0,
694                                                          audit_info->loginuid,
695                                                          audit_info->sessionid,
696                                                          audit_info->secid);
697                                 return err;
698                         }
699                 }
700                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
701                         hlist_for_each_entry(pol, entry,
702                                              net->xfrm.policy_bydst[dir].table + i,
703                                              bydst) {
704                                 if (pol->type != type)
705                                         continue;
706                                 err = security_xfrm_policy_delete(
707                                                                 pol->security);
708                                 if (err) {
709                                         xfrm_audit_policy_delete(pol, 0,
710                                                         audit_info->loginuid,
711                                                         audit_info->sessionid,
712                                                         audit_info->secid);
713                                         return err;
714                                 }
715                         }
716                 }
717         }
718         return err;
719 }
720 #else
721 static inline int
722 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
723 {
724         return 0;
725 }
726 #endif
727
728 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info)
729 {
730         int dir, err = 0, cnt = 0;
731
732         write_lock_bh(&xfrm_policy_lock);
733
734         err = xfrm_policy_flush_secctx_check(net, type, audit_info);
735         if (err)
736                 goto out;
737
738         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
739                 struct xfrm_policy *pol;
740                 struct hlist_node *entry;
741                 int i;
742
743         again1:
744                 hlist_for_each_entry(pol, entry,
745                                      &net->xfrm.policy_inexact[dir], bydst) {
746                         if (pol->type != type)
747                                 continue;
748                         __xfrm_policy_unlink(pol, dir);
749                         write_unlock_bh(&xfrm_policy_lock);
750                         cnt++;
751
752                         xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
753                                                  audit_info->sessionid,
754                                                  audit_info->secid);
755
756                         xfrm_policy_kill(pol);
757
758                         write_lock_bh(&xfrm_policy_lock);
759                         goto again1;
760                 }
761
762                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
763         again2:
764                         hlist_for_each_entry(pol, entry,
765                                              net->xfrm.policy_bydst[dir].table + i,
766                                              bydst) {
767                                 if (pol->type != type)
768                                         continue;
769                                 __xfrm_policy_unlink(pol, dir);
770                                 write_unlock_bh(&xfrm_policy_lock);
771                                 cnt++;
772
773                                 xfrm_audit_policy_delete(pol, 1,
774                                                          audit_info->loginuid,
775                                                          audit_info->sessionid,
776                                                          audit_info->secid);
777                                 xfrm_policy_kill(pol);
778
779                                 write_lock_bh(&xfrm_policy_lock);
780                                 goto again2;
781                         }
782                 }
783
784         }
785         if (!cnt)
786                 err = -ESRCH;
787 out:
788         write_unlock_bh(&xfrm_policy_lock);
789         return err;
790 }
791 EXPORT_SYMBOL(xfrm_policy_flush);
792
793 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
794                      int (*func)(struct xfrm_policy *, int, int, void*),
795                      void *data)
796 {
797         struct xfrm_policy *pol;
798         struct xfrm_policy_walk_entry *x;
799         int error = 0;
800
801         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
802             walk->type != XFRM_POLICY_TYPE_ANY)
803                 return -EINVAL;
804
805         if (list_empty(&walk->walk.all) && walk->seq != 0)
806                 return 0;
807
808         write_lock_bh(&xfrm_policy_lock);
809         if (list_empty(&walk->walk.all))
810                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
811         else
812                 x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
813         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
814                 if (x->dead)
815                         continue;
816                 pol = container_of(x, struct xfrm_policy, walk);
817                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
818                     walk->type != pol->type)
819                         continue;
820                 error = func(pol, xfrm_policy_id2dir(pol->index),
821                              walk->seq, data);
822                 if (error) {
823                         list_move_tail(&walk->walk.all, &x->all);
824                         goto out;
825                 }
826                 walk->seq++;
827         }
828         if (walk->seq == 0) {
829                 error = -ENOENT;
830                 goto out;
831         }
832         list_del_init(&walk->walk.all);
833 out:
834         write_unlock_bh(&xfrm_policy_lock);
835         return error;
836 }
837 EXPORT_SYMBOL(xfrm_policy_walk);
838
839 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
840 {
841         INIT_LIST_HEAD(&walk->walk.all);
842         walk->walk.dead = 1;
843         walk->type = type;
844         walk->seq = 0;
845 }
846 EXPORT_SYMBOL(xfrm_policy_walk_init);
847
848 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk)
849 {
850         if (list_empty(&walk->walk.all))
851                 return;
852
853         write_lock_bh(&xfrm_policy_lock);
854         list_del(&walk->walk.all);
855         write_unlock_bh(&xfrm_policy_lock);
856 }
857 EXPORT_SYMBOL(xfrm_policy_walk_done);
858
859 /*
860  * Find policy to apply to this flow.
861  *
862  * Returns 0 if policy found, else an -errno.
863  */
864 static int xfrm_policy_match(struct xfrm_policy *pol, struct flowi *fl,
865                              u8 type, u16 family, int dir)
866 {
867         struct xfrm_selector *sel = &pol->selector;
868         int match, ret = -ESRCH;
869
870         if (pol->family != family ||
871             (fl->mark & pol->mark.m) != pol->mark.v ||
872             pol->type != type)
873                 return ret;
874
875         match = xfrm_selector_match(sel, fl, family);
876         if (match)
877                 ret = security_xfrm_policy_lookup(pol->security, fl->secid,
878                                                   dir);
879
880         return ret;
881 }
882
883 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
884                                                      struct flowi *fl,
885                                                      u16 family, u8 dir)
886 {
887         int err;
888         struct xfrm_policy *pol, *ret;
889         xfrm_address_t *daddr, *saddr;
890         struct hlist_node *entry;
891         struct hlist_head *chain;
892         u32 priority = ~0U;
893
894         daddr = xfrm_flowi_daddr(fl, family);
895         saddr = xfrm_flowi_saddr(fl, family);
896         if (unlikely(!daddr || !saddr))
897                 return NULL;
898
899         read_lock_bh(&xfrm_policy_lock);
900         chain = policy_hash_direct(net, daddr, saddr, family, dir);
901         ret = NULL;
902         hlist_for_each_entry(pol, entry, chain, bydst) {
903                 err = xfrm_policy_match(pol, fl, type, family, dir);
904                 if (err) {
905                         if (err == -ESRCH)
906                                 continue;
907                         else {
908                                 ret = ERR_PTR(err);
909                                 goto fail;
910                         }
911                 } else {
912                         ret = pol;
913                         priority = ret->priority;
914                         break;
915                 }
916         }
917         chain = &net->xfrm.policy_inexact[dir];
918         hlist_for_each_entry(pol, entry, chain, bydst) {
919                 err = xfrm_policy_match(pol, fl, type, family, dir);
920                 if (err) {
921                         if (err == -ESRCH)
922                                 continue;
923                         else {
924                                 ret = ERR_PTR(err);
925                                 goto fail;
926                         }
927                 } else if (pol->priority < priority) {
928                         ret = pol;
929                         break;
930                 }
931         }
932         if (ret)
933                 xfrm_pol_hold(ret);
934 fail:
935         read_unlock_bh(&xfrm_policy_lock);
936
937         return ret;
938 }
939
940 static struct xfrm_policy *
941 __xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family, u8 dir)
942 {
943 #ifdef CONFIG_XFRM_SUB_POLICY
944         struct xfrm_policy *pol;
945
946         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
947         if (pol != NULL)
948                 return pol;
949 #endif
950         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
951 }
952
953 static struct flow_cache_object *
954 xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family,
955                    u8 dir, struct flow_cache_object *old_obj, void *ctx)
956 {
957         struct xfrm_policy *pol;
958
959         if (old_obj)
960                 xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
961
962         pol = __xfrm_policy_lookup(net, fl, family, dir);
963         if (IS_ERR_OR_NULL(pol))
964                 return ERR_CAST(pol);
965
966         /* Resolver returns two references:
967          * one for cache and one for caller of flow_cache_lookup() */
968         xfrm_pol_hold(pol);
969
970         return &pol->flo;
971 }
972
973 static inline int policy_to_flow_dir(int dir)
974 {
975         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
976             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
977             XFRM_POLICY_FWD == FLOW_DIR_FWD)
978                 return dir;
979         switch (dir) {
980         default:
981         case XFRM_POLICY_IN:
982                 return FLOW_DIR_IN;
983         case XFRM_POLICY_OUT:
984                 return FLOW_DIR_OUT;
985         case XFRM_POLICY_FWD:
986                 return FLOW_DIR_FWD;
987         }
988 }
989
990 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
991 {
992         struct xfrm_policy *pol;
993
994         read_lock_bh(&xfrm_policy_lock);
995         if ((pol = sk->sk_policy[dir]) != NULL) {
996                 int match = xfrm_selector_match(&pol->selector, fl,
997                                                 sk->sk_family);
998                 int err = 0;
999
1000                 if (match) {
1001                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1002                                 pol = NULL;
1003                                 goto out;
1004                         }
1005                         err = security_xfrm_policy_lookup(pol->security,
1006                                                       fl->secid,
1007                                                       policy_to_flow_dir(dir));
1008                         if (!err)
1009                                 xfrm_pol_hold(pol);
1010                         else if (err == -ESRCH)
1011                                 pol = NULL;
1012                         else
1013                                 pol = ERR_PTR(err);
1014                 } else
1015                         pol = NULL;
1016         }
1017 out:
1018         read_unlock_bh(&xfrm_policy_lock);
1019         return pol;
1020 }
1021
1022 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1023 {
1024         struct net *net = xp_net(pol);
1025         struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1026                                                      pol->family, dir);
1027
1028         list_add(&pol->walk.all, &net->xfrm.policy_all);
1029         hlist_add_head(&pol->bydst, chain);
1030         hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1031         net->xfrm.policy_count[dir]++;
1032         xfrm_pol_hold(pol);
1033
1034         if (xfrm_bydst_should_resize(net, dir, NULL))
1035                 schedule_work(&net->xfrm.policy_hash_work);
1036 }
1037
1038 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1039                                                 int dir)
1040 {
1041         struct net *net = xp_net(pol);
1042
1043         if (hlist_unhashed(&pol->bydst))
1044                 return NULL;
1045
1046         hlist_del(&pol->bydst);
1047         hlist_del(&pol->byidx);
1048         list_del(&pol->walk.all);
1049         net->xfrm.policy_count[dir]--;
1050
1051         return pol;
1052 }
1053
1054 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1055 {
1056         write_lock_bh(&xfrm_policy_lock);
1057         pol = __xfrm_policy_unlink(pol, dir);
1058         write_unlock_bh(&xfrm_policy_lock);
1059         if (pol) {
1060                 xfrm_policy_kill(pol);
1061                 return 0;
1062         }
1063         return -ENOENT;
1064 }
1065 EXPORT_SYMBOL(xfrm_policy_delete);
1066
1067 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1068 {
1069         struct net *net = xp_net(pol);
1070         struct xfrm_policy *old_pol;
1071
1072 #ifdef CONFIG_XFRM_SUB_POLICY
1073         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1074                 return -EINVAL;
1075 #endif
1076
1077         write_lock_bh(&xfrm_policy_lock);
1078         old_pol = sk->sk_policy[dir];
1079         sk->sk_policy[dir] = pol;
1080         if (pol) {
1081                 pol->curlft.add_time = get_seconds();
1082                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir);
1083                 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1084         }
1085         if (old_pol)
1086                 /* Unlinking succeeds always. This is the only function
1087                  * allowed to delete or replace socket policy.
1088                  */
1089                 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1090         write_unlock_bh(&xfrm_policy_lock);
1091
1092         if (old_pol) {
1093                 xfrm_policy_kill(old_pol);
1094         }
1095         return 0;
1096 }
1097
1098 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
1099 {
1100         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1101
1102         if (newp) {
1103                 newp->selector = old->selector;
1104                 if (security_xfrm_policy_clone(old->security,
1105                                                &newp->security)) {
1106                         kfree(newp);
1107                         return NULL;  /* ENOMEM */
1108                 }
1109                 newp->lft = old->lft;
1110                 newp->curlft = old->curlft;
1111                 newp->mark = old->mark;
1112                 newp->action = old->action;
1113                 newp->flags = old->flags;
1114                 newp->xfrm_nr = old->xfrm_nr;
1115                 newp->index = old->index;
1116                 newp->type = old->type;
1117                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1118                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1119                 write_lock_bh(&xfrm_policy_lock);
1120                 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1121                 write_unlock_bh(&xfrm_policy_lock);
1122                 xfrm_pol_put(newp);
1123         }
1124         return newp;
1125 }
1126
1127 int __xfrm_sk_clone_policy(struct sock *sk)
1128 {
1129         struct xfrm_policy *p0 = sk->sk_policy[0],
1130                            *p1 = sk->sk_policy[1];
1131
1132         sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1133         if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1134                 return -ENOMEM;
1135         if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1136                 return -ENOMEM;
1137         return 0;
1138 }
1139
1140 static int
1141 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1142                unsigned short family)
1143 {
1144         int err;
1145         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1146
1147         if (unlikely(afinfo == NULL))
1148                 return -EINVAL;
1149         err = afinfo->get_saddr(net, local, remote);
1150         xfrm_policy_put_afinfo(afinfo);
1151         return err;
1152 }
1153
1154 /* Resolve list of templates for the flow, given policy. */
1155
1156 static int
1157 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, struct flowi *fl,
1158                       struct xfrm_state **xfrm,
1159                       unsigned short family)
1160 {
1161         struct net *net = xp_net(policy);
1162         int nx;
1163         int i, error;
1164         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1165         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1166         xfrm_address_t tmp;
1167
1168         for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1169                 struct xfrm_state *x;
1170                 xfrm_address_t *remote = daddr;
1171                 xfrm_address_t *local  = saddr;
1172                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1173
1174                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1175                     tmpl->mode == XFRM_MODE_BEET) {
1176                         remote = &tmpl->id.daddr;
1177                         local = &tmpl->saddr;
1178                         family = tmpl->encap_family;
1179                         if (xfrm_addr_any(local, family)) {
1180                                 error = xfrm_get_saddr(net, &tmp, remote, family);
1181                                 if (error)
1182                                         goto fail;
1183                                 local = &tmp;
1184                         }
1185                 }
1186
1187                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1188
1189                 if (x && x->km.state == XFRM_STATE_VALID) {
1190                         xfrm[nx++] = x;
1191                         daddr = remote;
1192                         saddr = local;
1193                         continue;
1194                 }
1195                 if (x) {
1196                         error = (x->km.state == XFRM_STATE_ERROR ?
1197                                  -EINVAL : -EAGAIN);
1198                         xfrm_state_put(x);
1199                 }
1200                 else if (error == -ESRCH)
1201                         error = -EAGAIN;
1202
1203                 if (!tmpl->optional)
1204                         goto fail;
1205         }
1206         return nx;
1207
1208 fail:
1209         for (nx--; nx>=0; nx--)
1210                 xfrm_state_put(xfrm[nx]);
1211         return error;
1212 }
1213
1214 static int
1215 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
1216                   struct xfrm_state **xfrm,
1217                   unsigned short family)
1218 {
1219         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1220         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1221         int cnx = 0;
1222         int error;
1223         int ret;
1224         int i;
1225
1226         for (i = 0; i < npols; i++) {
1227                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1228                         error = -ENOBUFS;
1229                         goto fail;
1230                 }
1231
1232                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1233                 if (ret < 0) {
1234                         error = ret;
1235                         goto fail;
1236                 } else
1237                         cnx += ret;
1238         }
1239
1240         /* found states are sorted for outbound processing */
1241         if (npols > 1)
1242                 xfrm_state_sort(xfrm, tpp, cnx, family);
1243
1244         return cnx;
1245
1246  fail:
1247         for (cnx--; cnx>=0; cnx--)
1248                 xfrm_state_put(tpp[cnx]);
1249         return error;
1250
1251 }
1252
1253 /* Check that the bundle accepts the flow and its components are
1254  * still valid.
1255  */
1256
1257 static inline int xfrm_get_tos(struct flowi *fl, int family)
1258 {
1259         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1260         int tos;
1261
1262         if (!afinfo)
1263                 return -EINVAL;
1264
1265         tos = afinfo->get_tos(fl);
1266
1267         xfrm_policy_put_afinfo(afinfo);
1268
1269         return tos;
1270 }
1271
1272 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1273 {
1274         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1275         struct dst_entry *dst = &xdst->u.dst;
1276
1277         if (xdst->route == NULL) {
1278                 /* Dummy bundle - if it has xfrms we were not
1279                  * able to build bundle as template resolution failed.
1280                  * It means we need to try again resolving. */
1281                 if (xdst->num_xfrms > 0)
1282                         return NULL;
1283         } else {
1284                 /* Real bundle */
1285                 if (stale_bundle(dst))
1286                         return NULL;
1287         }
1288
1289         dst_hold(dst);
1290         return flo;
1291 }
1292
1293 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1294 {
1295         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1296         struct dst_entry *dst = &xdst->u.dst;
1297
1298         if (!xdst->route)
1299                 return 0;
1300         if (stale_bundle(dst))
1301                 return 0;
1302
1303         return 1;
1304 }
1305
1306 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1307 {
1308         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1309         struct dst_entry *dst = &xdst->u.dst;
1310
1311         dst_free(dst);
1312 }
1313
1314 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1315         .get = xfrm_bundle_flo_get,
1316         .check = xfrm_bundle_flo_check,
1317         .delete = xfrm_bundle_flo_delete,
1318 };
1319
1320 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1321 {
1322         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1323         struct dst_ops *dst_ops;
1324         struct xfrm_dst *xdst;
1325
1326         if (!afinfo)
1327                 return ERR_PTR(-EINVAL);
1328
1329         switch (family) {
1330         case AF_INET:
1331                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1332                 break;
1333 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1334         case AF_INET6:
1335                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1336                 break;
1337 #endif
1338         default:
1339                 BUG();
1340         }
1341         xdst = dst_alloc(dst_ops) ?: ERR_PTR(-ENOBUFS);
1342         xfrm_policy_put_afinfo(afinfo);
1343
1344         xdst->flo.ops = &xfrm_bundle_fc_ops;
1345
1346         return xdst;
1347 }
1348
1349 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1350                                  int nfheader_len)
1351 {
1352         struct xfrm_policy_afinfo *afinfo =
1353                 xfrm_policy_get_afinfo(dst->ops->family);
1354         int err;
1355
1356         if (!afinfo)
1357                 return -EINVAL;
1358
1359         err = afinfo->init_path(path, dst, nfheader_len);
1360
1361         xfrm_policy_put_afinfo(afinfo);
1362
1363         return err;
1364 }
1365
1366 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1367                                 struct flowi *fl)
1368 {
1369         struct xfrm_policy_afinfo *afinfo =
1370                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1371         int err;
1372
1373         if (!afinfo)
1374                 return -EINVAL;
1375
1376         err = afinfo->fill_dst(xdst, dev, fl);
1377
1378         xfrm_policy_put_afinfo(afinfo);
1379
1380         return err;
1381 }
1382
1383
1384 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1385  * all the metrics... Shortly, bundle a bundle.
1386  */
1387
1388 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1389                                             struct xfrm_state **xfrm, int nx,
1390                                             struct flowi *fl,
1391                                             struct dst_entry *dst)
1392 {
1393         struct net *net = xp_net(policy);
1394         unsigned long now = jiffies;
1395         struct net_device *dev;
1396         struct dst_entry *dst_prev = NULL;
1397         struct dst_entry *dst0 = NULL;
1398         int i = 0;
1399         int err;
1400         int header_len = 0;
1401         int nfheader_len = 0;
1402         int trailer_len = 0;
1403         int tos;
1404         int family = policy->selector.family;
1405         xfrm_address_t saddr, daddr;
1406
1407         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1408
1409         tos = xfrm_get_tos(fl, family);
1410         err = tos;
1411         if (tos < 0)
1412                 goto put_states;
1413
1414         dst_hold(dst);
1415
1416         for (; i < nx; i++) {
1417                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1418                 struct dst_entry *dst1 = &xdst->u.dst;
1419
1420                 err = PTR_ERR(xdst);
1421                 if (IS_ERR(xdst)) {
1422                         dst_release(dst);
1423                         goto put_states;
1424                 }
1425
1426                 if (!dst_prev)
1427                         dst0 = dst1;
1428                 else {
1429                         dst_prev->child = dst_clone(dst1);
1430                         dst1->flags |= DST_NOHASH;
1431                 }
1432
1433                 xdst->route = dst;
1434                 memcpy(&dst1->metrics, &dst->metrics, sizeof(dst->metrics));
1435
1436                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1437                         family = xfrm[i]->props.family;
1438                         dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1439                                               family);
1440                         err = PTR_ERR(dst);
1441                         if (IS_ERR(dst))
1442                                 goto put_states;
1443                 } else
1444                         dst_hold(dst);
1445
1446                 dst1->xfrm = xfrm[i];
1447                 xdst->xfrm_genid = xfrm[i]->genid;
1448
1449                 dst1->obsolete = -1;
1450                 dst1->flags |= DST_HOST;
1451                 dst1->lastuse = now;
1452
1453                 dst1->input = dst_discard;
1454                 dst1->output = xfrm[i]->outer_mode->afinfo->output;
1455
1456                 dst1->next = dst_prev;
1457                 dst_prev = dst1;
1458
1459                 header_len += xfrm[i]->props.header_len;
1460                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1461                         nfheader_len += xfrm[i]->props.header_len;
1462                 trailer_len += xfrm[i]->props.trailer_len;
1463         }
1464
1465         dst_prev->child = dst;
1466         dst0->path = dst;
1467
1468         err = -ENODEV;
1469         dev = dst->dev;
1470         if (!dev)
1471                 goto free_dst;
1472
1473         /* Copy neighbour for reachability confirmation */
1474         dst0->neighbour = neigh_clone(dst->neighbour);
1475
1476         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1477         xfrm_init_pmtu(dst_prev);
1478
1479         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1480                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1481
1482                 err = xfrm_fill_dst(xdst, dev, fl);
1483                 if (err)
1484                         goto free_dst;
1485
1486                 dst_prev->header_len = header_len;
1487                 dst_prev->trailer_len = trailer_len;
1488                 header_len -= xdst->u.dst.xfrm->props.header_len;
1489                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1490         }
1491
1492 out:
1493         return dst0;
1494
1495 put_states:
1496         for (; i < nx; i++)
1497                 xfrm_state_put(xfrm[i]);
1498 free_dst:
1499         if (dst0)
1500                 dst_free(dst0);
1501         dst0 = ERR_PTR(err);
1502         goto out;
1503 }
1504
1505 static int inline
1506 xfrm_dst_alloc_copy(void **target, void *src, int size)
1507 {
1508         if (!*target) {
1509                 *target = kmalloc(size, GFP_ATOMIC);
1510                 if (!*target)
1511                         return -ENOMEM;
1512         }
1513         memcpy(*target, src, size);
1514         return 0;
1515 }
1516
1517 static int inline
1518 xfrm_dst_update_parent(struct dst_entry *dst, struct xfrm_selector *sel)
1519 {
1520 #ifdef CONFIG_XFRM_SUB_POLICY
1521         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1522         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1523                                    sel, sizeof(*sel));
1524 #else
1525         return 0;
1526 #endif
1527 }
1528
1529 static int inline
1530 xfrm_dst_update_origin(struct dst_entry *dst, struct flowi *fl)
1531 {
1532 #ifdef CONFIG_XFRM_SUB_POLICY
1533         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1534         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1535 #else
1536         return 0;
1537 #endif
1538 }
1539
1540 static int xfrm_expand_policies(struct flowi *fl, u16 family,
1541                                 struct xfrm_policy **pols,
1542                                 int *num_pols, int *num_xfrms)
1543 {
1544         int i;
1545
1546         if (*num_pols == 0 || !pols[0]) {
1547                 *num_pols = 0;
1548                 *num_xfrms = 0;
1549                 return 0;
1550         }
1551         if (IS_ERR(pols[0]))
1552                 return PTR_ERR(pols[0]);
1553
1554         *num_xfrms = pols[0]->xfrm_nr;
1555
1556 #ifdef CONFIG_XFRM_SUB_POLICY
1557         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1558             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1559                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1560                                                     XFRM_POLICY_TYPE_MAIN,
1561                                                     fl, family,
1562                                                     XFRM_POLICY_OUT);
1563                 if (pols[1]) {
1564                         if (IS_ERR(pols[1])) {
1565                                 xfrm_pols_put(pols, *num_pols);
1566                                 return PTR_ERR(pols[1]);
1567                         }
1568                         (*num_pols) ++;
1569                         (*num_xfrms) += pols[1]->xfrm_nr;
1570                 }
1571         }
1572 #endif
1573         for (i = 0; i < *num_pols; i++) {
1574                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1575                         *num_xfrms = -1;
1576                         break;
1577                 }
1578         }
1579
1580         return 0;
1581
1582 }
1583
1584 static struct xfrm_dst *
1585 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1586                                struct flowi *fl, u16 family,
1587                                struct dst_entry *dst_orig)
1588 {
1589         struct net *net = xp_net(pols[0]);
1590         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1591         struct dst_entry *dst;
1592         struct xfrm_dst *xdst;
1593         int err;
1594
1595         /* Try to instantiate a bundle */
1596         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1597         if (err < 0) {
1598                 if (err != -EAGAIN)
1599                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1600                 return ERR_PTR(err);
1601         }
1602
1603         dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1604         if (IS_ERR(dst)) {
1605                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1606                 return ERR_CAST(dst);
1607         }
1608
1609         xdst = (struct xfrm_dst *)dst;
1610         xdst->num_xfrms = err;
1611         if (num_pols > 1)
1612                 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1613         else
1614                 err = xfrm_dst_update_origin(dst, fl);
1615         if (unlikely(err)) {
1616                 dst_free(dst);
1617                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1618                 return ERR_PTR(err);
1619         }
1620
1621         xdst->num_pols = num_pols;
1622         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1623         xdst->policy_genid = atomic_read(&pols[0]->genid);
1624
1625         return xdst;
1626 }
1627
1628 static struct flow_cache_object *
1629 xfrm_bundle_lookup(struct net *net, struct flowi *fl, u16 family, u8 dir,
1630                    struct flow_cache_object *oldflo, void *ctx)
1631 {
1632         struct dst_entry *dst_orig = (struct dst_entry *)ctx;
1633         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1634         struct xfrm_dst *xdst, *new_xdst;
1635         int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
1636
1637         /* Check if the policies from old bundle are usable */
1638         xdst = NULL;
1639         if (oldflo) {
1640                 xdst = container_of(oldflo, struct xfrm_dst, flo);
1641                 num_pols = xdst->num_pols;
1642                 num_xfrms = xdst->num_xfrms;
1643                 pol_dead = 0;
1644                 for (i = 0; i < num_pols; i++) {
1645                         pols[i] = xdst->pols[i];
1646                         pol_dead |= pols[i]->walk.dead;
1647                 }
1648                 if (pol_dead) {
1649                         dst_free(&xdst->u.dst);
1650                         xdst = NULL;
1651                         num_pols = 0;
1652                         num_xfrms = 0;
1653                         oldflo = NULL;
1654                 }
1655         }
1656
1657         /* Resolve policies to use if we couldn't get them from
1658          * previous cache entry */
1659         if (xdst == NULL) {
1660                 num_pols = 1;
1661                 pols[0] = __xfrm_policy_lookup(net, fl, family, dir);
1662                 err = xfrm_expand_policies(fl, family, pols,
1663                                            &num_pols, &num_xfrms);
1664                 if (err < 0)
1665                         goto inc_error;
1666                 if (num_pols == 0)
1667                         return NULL;
1668                 if (num_xfrms <= 0)
1669                         goto make_dummy_bundle;
1670         }
1671
1672         new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, dst_orig);
1673         if (IS_ERR(new_xdst)) {
1674                 err = PTR_ERR(new_xdst);
1675                 if (err != -EAGAIN)
1676                         goto error;
1677                 if (oldflo == NULL)
1678                         goto make_dummy_bundle;
1679                 dst_hold(&xdst->u.dst);
1680                 return oldflo;
1681         }
1682
1683         /* Kill the previous bundle */
1684         if (xdst) {
1685                 /* The policies were stolen for newly generated bundle */
1686                 xdst->num_pols = 0;
1687                 dst_free(&xdst->u.dst);
1688         }
1689
1690         /* Flow cache does not have reference, it dst_free()'s,
1691          * but we do need to return one reference for original caller */
1692         dst_hold(&new_xdst->u.dst);
1693         return &new_xdst->flo;
1694
1695 make_dummy_bundle:
1696         /* We found policies, but there's no bundles to instantiate:
1697          * either because the policy blocks, has no transformations or
1698          * we could not build template (no xfrm_states).*/
1699         xdst = xfrm_alloc_dst(net, family);
1700         if (IS_ERR(xdst)) {
1701                 xfrm_pols_put(pols, num_pols);
1702                 return ERR_CAST(xdst);
1703         }
1704         xdst->num_pols = num_pols;
1705         xdst->num_xfrms = num_xfrms;
1706         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1707
1708         dst_hold(&xdst->u.dst);
1709         return &xdst->flo;
1710
1711 inc_error:
1712         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1713 error:
1714         if (xdst != NULL)
1715                 dst_free(&xdst->u.dst);
1716         else
1717                 xfrm_pols_put(pols, num_pols);
1718         return ERR_PTR(err);
1719 }
1720
1721 /* Main function: finds/creates a bundle for given flow.
1722  *
1723  * At the moment we eat a raw IP route. Mostly to speed up lookups
1724  * on interfaces with disabled IPsec.
1725  */
1726 int __xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
1727                   struct sock *sk, int flags)
1728 {
1729         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1730         struct flow_cache_object *flo;
1731         struct xfrm_dst *xdst;
1732         struct dst_entry *dst, *dst_orig = *dst_p, *route;
1733         u16 family = dst_orig->ops->family;
1734         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
1735         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
1736
1737 restart:
1738         dst = NULL;
1739         xdst = NULL;
1740         route = NULL;
1741
1742         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
1743                 num_pols = 1;
1744                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
1745                 err = xfrm_expand_policies(fl, family, pols,
1746                                            &num_pols, &num_xfrms);
1747                 if (err < 0)
1748                         goto dropdst;
1749
1750                 if (num_pols) {
1751                         if (num_xfrms <= 0) {
1752                                 drop_pols = num_pols;
1753                                 goto no_transform;
1754                         }
1755
1756                         xdst = xfrm_resolve_and_create_bundle(
1757                                         pols, num_pols, fl,
1758                                         family, dst_orig);
1759                         if (IS_ERR(xdst)) {
1760                                 xfrm_pols_put(pols, num_pols);
1761                                 err = PTR_ERR(xdst);
1762                                 goto dropdst;
1763                         }
1764
1765                         spin_lock_bh(&xfrm_policy_sk_bundle_lock);
1766                         xdst->u.dst.next = xfrm_policy_sk_bundles;
1767                         xfrm_policy_sk_bundles = &xdst->u.dst;
1768                         spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
1769
1770                         route = xdst->route;
1771                 }
1772         }
1773
1774         if (xdst == NULL) {
1775                 /* To accelerate a bit...  */
1776                 if ((dst_orig->flags & DST_NOXFRM) ||
1777                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
1778                         goto nopol;
1779
1780                 flo = flow_cache_lookup(net, fl, family, dir,
1781                                         xfrm_bundle_lookup, dst_orig);
1782                 if (flo == NULL)
1783                         goto nopol;
1784                 if (IS_ERR(flo)) {
1785                         err = PTR_ERR(flo);
1786                         goto dropdst;
1787                 }
1788                 xdst = container_of(flo, struct xfrm_dst, flo);
1789
1790                 num_pols = xdst->num_pols;
1791                 num_xfrms = xdst->num_xfrms;
1792                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy*) * num_pols);
1793                 route = xdst->route;
1794         }
1795
1796         dst = &xdst->u.dst;
1797         if (route == NULL && num_xfrms > 0) {
1798                 /* The only case when xfrm_bundle_lookup() returns a
1799                  * bundle with null route, is when the template could
1800                  * not be resolved. It means policies are there, but
1801                  * bundle could not be created, since we don't yet
1802                  * have the xfrm_state's. We need to wait for KM to
1803                  * negotiate new SA's or bail out with error.*/
1804                 if (net->xfrm.sysctl_larval_drop) {
1805                         /* EREMOTE tells the caller to generate
1806                          * a one-shot blackhole route. */
1807                         dst_release(dst);
1808                         xfrm_pols_put(pols, drop_pols);
1809                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1810                         return -EREMOTE;
1811                 }
1812                 if (flags & XFRM_LOOKUP_WAIT) {
1813                         DECLARE_WAITQUEUE(wait, current);
1814
1815                         add_wait_queue(&net->xfrm.km_waitq, &wait);
1816                         set_current_state(TASK_INTERRUPTIBLE);
1817                         schedule();
1818                         set_current_state(TASK_RUNNING);
1819                         remove_wait_queue(&net->xfrm.km_waitq, &wait);
1820
1821                         if (!signal_pending(current)) {
1822                                 dst_release(dst);
1823                                 goto restart;
1824                         }
1825
1826                         err = -ERESTART;
1827                 } else
1828                         err = -EAGAIN;
1829
1830                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1831                 goto error;
1832         }
1833
1834 no_transform:
1835         if (num_pols == 0)
1836                 goto nopol;
1837
1838         if ((flags & XFRM_LOOKUP_ICMP) &&
1839             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
1840                 err = -ENOENT;
1841                 goto error;
1842         }
1843
1844         for (i = 0; i < num_pols; i++)
1845                 pols[i]->curlft.use_time = get_seconds();
1846
1847         if (num_xfrms < 0) {
1848                 /* Prohibit the flow */
1849                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
1850                 err = -EPERM;
1851                 goto error;
1852         } else if (num_xfrms > 0) {
1853                 /* Flow transformed */
1854                 *dst_p = dst;
1855                 dst_release(dst_orig);
1856         } else {
1857                 /* Flow passes untransformed */
1858                 dst_release(dst);
1859         }
1860 ok:
1861         xfrm_pols_put(pols, drop_pols);
1862         return 0;
1863
1864 nopol:
1865         if (!(flags & XFRM_LOOKUP_ICMP))
1866                 goto ok;
1867         err = -ENOENT;
1868 error:
1869         dst_release(dst);
1870 dropdst:
1871         dst_release(dst_orig);
1872         *dst_p = NULL;
1873         xfrm_pols_put(pols, drop_pols);
1874         return err;
1875 }
1876 EXPORT_SYMBOL(__xfrm_lookup);
1877
1878 int xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
1879                 struct sock *sk, int flags)
1880 {
1881         int err = __xfrm_lookup(net, dst_p, fl, sk, flags);
1882
1883         if (err == -EREMOTE) {
1884                 dst_release(*dst_p);
1885                 *dst_p = NULL;
1886                 err = -EAGAIN;
1887         }
1888
1889         return err;
1890 }
1891 EXPORT_SYMBOL(xfrm_lookup);
1892
1893 static inline int
1894 xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
1895 {
1896         struct xfrm_state *x;
1897
1898         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1899                 return 0;
1900         x = skb->sp->xvec[idx];
1901         if (!x->type->reject)
1902                 return 0;
1903         return x->type->reject(x, skb, fl);
1904 }
1905
1906 /* When skb is transformed back to its "native" form, we have to
1907  * check policy restrictions. At the moment we make this in maximally
1908  * stupid way. Shame on me. :-) Of course, connected sockets must
1909  * have policy cached at them.
1910  */
1911
1912 static inline int
1913 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
1914               unsigned short family)
1915 {
1916         if (xfrm_state_kern(x))
1917                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
1918         return  x->id.proto == tmpl->id.proto &&
1919                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1920                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1921                 x->props.mode == tmpl->mode &&
1922                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
1923                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1924                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
1925                   xfrm_state_addr_cmp(tmpl, x, family));
1926 }
1927
1928 /*
1929  * 0 or more than 0 is returned when validation is succeeded (either bypass
1930  * because of optional transport mode, or next index of the mathced secpath
1931  * state with the template.
1932  * -1 is returned when no matching template is found.
1933  * Otherwise "-2 - errored_index" is returned.
1934  */
1935 static inline int
1936 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1937                unsigned short family)
1938 {
1939         int idx = start;
1940
1941         if (tmpl->optional) {
1942                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
1943                         return start;
1944         } else
1945                 start = -1;
1946         for (; idx < sp->len; idx++) {
1947                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1948                         return ++idx;
1949                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
1950                         if (start == -1)
1951                                 start = -2-idx;
1952                         break;
1953                 }
1954         }
1955         return start;
1956 }
1957
1958 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1959                           unsigned int family, int reverse)
1960 {
1961         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1962         int err;
1963
1964         if (unlikely(afinfo == NULL))
1965                 return -EAFNOSUPPORT;
1966
1967         afinfo->decode_session(skb, fl, reverse);
1968         err = security_xfrm_decode_session(skb, &fl->secid);
1969         xfrm_policy_put_afinfo(afinfo);
1970         return err;
1971 }
1972 EXPORT_SYMBOL(__xfrm_decode_session);
1973
1974 static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
1975 {
1976         for (; k < sp->len; k++) {
1977                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
1978                         *idxp = k;
1979                         return 1;
1980                 }
1981         }
1982
1983         return 0;
1984 }
1985
1986 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
1987                         unsigned short family)
1988 {
1989         struct net *net = dev_net(skb->dev);
1990         struct xfrm_policy *pol;
1991         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1992         int npols = 0;
1993         int xfrm_nr;
1994         int pi;
1995         int reverse;
1996         struct flowi fl;
1997         u8 fl_dir;
1998         int xerr_idx = -1;
1999
2000         reverse = dir & ~XFRM_POLICY_MASK;
2001         dir &= XFRM_POLICY_MASK;
2002         fl_dir = policy_to_flow_dir(dir);
2003
2004         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2005                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2006                 return 0;
2007         }
2008
2009         nf_nat_decode_session(skb, &fl, family);
2010
2011         /* First, check used SA against their selectors. */
2012         if (skb->sp) {
2013                 int i;
2014
2015                 for (i=skb->sp->len-1; i>=0; i--) {
2016                         struct xfrm_state *x = skb->sp->xvec[i];
2017                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2018                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2019                                 return 0;
2020                         }
2021                 }
2022         }
2023
2024         pol = NULL;
2025         if (sk && sk->sk_policy[dir]) {
2026                 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2027                 if (IS_ERR(pol)) {
2028                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2029                         return 0;
2030                 }
2031         }
2032
2033         if (!pol) {
2034                 struct flow_cache_object *flo;
2035
2036                 flo = flow_cache_lookup(net, &fl, family, fl_dir,
2037                                         xfrm_policy_lookup, NULL);
2038                 if (IS_ERR_OR_NULL(flo))
2039                         pol = ERR_CAST(flo);
2040                 else
2041                         pol = container_of(flo, struct xfrm_policy, flo);
2042         }
2043
2044         if (IS_ERR(pol)) {
2045                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2046                 return 0;
2047         }
2048
2049         if (!pol) {
2050                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2051                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2052                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2053                         return 0;
2054                 }
2055                 return 1;
2056         }
2057
2058         pol->curlft.use_time = get_seconds();
2059
2060         pols[0] = pol;
2061         npols ++;
2062 #ifdef CONFIG_XFRM_SUB_POLICY
2063         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2064                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2065                                                     &fl, family,
2066                                                     XFRM_POLICY_IN);
2067                 if (pols[1]) {
2068                         if (IS_ERR(pols[1])) {
2069                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2070                                 return 0;
2071                         }
2072                         pols[1]->curlft.use_time = get_seconds();
2073                         npols ++;
2074                 }
2075         }
2076 #endif
2077
2078         if (pol->action == XFRM_POLICY_ALLOW) {
2079                 struct sec_path *sp;
2080                 static struct sec_path dummy;
2081                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2082                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2083                 struct xfrm_tmpl **tpp = tp;
2084                 int ti = 0;
2085                 int i, k;
2086
2087                 if ((sp = skb->sp) == NULL)
2088                         sp = &dummy;
2089
2090                 for (pi = 0; pi < npols; pi++) {
2091                         if (pols[pi] != pol &&
2092                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2093                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2094                                 goto reject;
2095                         }
2096                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2097                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2098                                 goto reject_error;
2099                         }
2100                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2101                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2102                 }
2103                 xfrm_nr = ti;
2104                 if (npols > 1) {
2105                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
2106                         tpp = stp;
2107                 }
2108
2109                 /* For each tunnel xfrm, find the first matching tmpl.
2110                  * For each tmpl before that, find corresponding xfrm.
2111                  * Order is _important_. Later we will implement
2112                  * some barriers, but at the moment barriers
2113                  * are implied between each two transformations.
2114                  */
2115                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2116                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2117                         if (k < 0) {
2118                                 if (k < -1)
2119                                         /* "-2 - errored_index" returned */
2120                                         xerr_idx = -(2+k);
2121                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2122                                 goto reject;
2123                         }
2124                 }
2125
2126                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2127                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2128                         goto reject;
2129                 }
2130
2131                 xfrm_pols_put(pols, npols);
2132                 return 1;
2133         }
2134         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2135
2136 reject:
2137         xfrm_secpath_reject(xerr_idx, skb, &fl);
2138 reject_error:
2139         xfrm_pols_put(pols, npols);
2140         return 0;
2141 }
2142 EXPORT_SYMBOL(__xfrm_policy_check);
2143
2144 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2145 {
2146         struct net *net = dev_net(skb->dev);
2147         struct flowi fl;
2148         struct dst_entry *dst;
2149         int res;
2150
2151         if (xfrm_decode_session(skb, &fl, family) < 0) {
2152                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2153                 return 0;
2154         }
2155
2156         dst = skb_dst(skb);
2157
2158         res = xfrm_lookup(net, &dst, &fl, NULL, 0) == 0;
2159         skb_dst_set(skb, dst);
2160         return res;
2161 }
2162 EXPORT_SYMBOL(__xfrm_route_forward);
2163
2164 /* Optimize later using cookies and generation ids. */
2165
2166 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2167 {
2168         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2169          * to "-1" to force all XFRM destinations to get validated by
2170          * dst_ops->check on every use.  We do this because when a
2171          * normal route referenced by an XFRM dst is obsoleted we do
2172          * not go looking around for all parent referencing XFRM dsts
2173          * so that we can invalidate them.  It is just too much work.
2174          * Instead we make the checks here on every use.  For example:
2175          *
2176          *      XFRM dst A --> IPv4 dst X
2177          *
2178          * X is the "xdst->route" of A (X is also the "dst->path" of A
2179          * in this example).  If X is marked obsolete, "A" will not
2180          * notice.  That's what we are validating here via the
2181          * stale_bundle() check.
2182          *
2183          * When a policy's bundle is pruned, we dst_free() the XFRM
2184          * dst which causes it's ->obsolete field to be set to a
2185          * positive non-zero integer.  If an XFRM dst has been pruned
2186          * like this, we want to force a new route lookup.
2187          */
2188         if (dst->obsolete < 0 && !stale_bundle(dst))
2189                 return dst;
2190
2191         return NULL;
2192 }
2193
2194 static int stale_bundle(struct dst_entry *dst)
2195 {
2196         return !xfrm_bundle_ok(NULL, (struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
2197 }
2198
2199 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2200 {
2201         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2202                 dst->dev = dev_net(dev)->loopback_dev;
2203                 dev_hold(dst->dev);
2204                 dev_put(dev);
2205         }
2206 }
2207 EXPORT_SYMBOL(xfrm_dst_ifdown);
2208
2209 static void xfrm_link_failure(struct sk_buff *skb)
2210 {
2211         /* Impossible. Such dst must be popped before reaches point of failure. */
2212         return;
2213 }
2214
2215 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2216 {
2217         if (dst) {
2218                 if (dst->obsolete) {
2219                         dst_release(dst);
2220                         dst = NULL;
2221                 }
2222         }
2223         return dst;
2224 }
2225
2226 static void __xfrm_garbage_collect(struct net *net)
2227 {
2228         struct dst_entry *head, *next;
2229
2230         flow_cache_flush();
2231
2232         spin_lock_bh(&xfrm_policy_sk_bundle_lock);
2233         head = xfrm_policy_sk_bundles;
2234         xfrm_policy_sk_bundles = NULL;
2235         spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
2236
2237         while (head) {
2238                 next = head->next;
2239                 dst_free(head);
2240                 head = next;
2241         }
2242 }
2243
2244 static void xfrm_init_pmtu(struct dst_entry *dst)
2245 {
2246         do {
2247                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2248                 u32 pmtu, route_mtu_cached;
2249
2250                 pmtu = dst_mtu(dst->child);
2251                 xdst->child_mtu_cached = pmtu;
2252
2253                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2254
2255                 route_mtu_cached = dst_mtu(xdst->route);
2256                 xdst->route_mtu_cached = route_mtu_cached;
2257
2258                 if (pmtu > route_mtu_cached)
2259                         pmtu = route_mtu_cached;
2260
2261                 dst->metrics[RTAX_MTU-1] = pmtu;
2262         } while ((dst = dst->next));
2263 }
2264
2265 /* Check that the bundle accepts the flow and its components are
2266  * still valid.
2267  */
2268
2269 int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
2270                 struct flowi *fl, int family, int strict)
2271 {
2272         struct dst_entry *dst = &first->u.dst;
2273         struct xfrm_dst *last;
2274         u32 mtu;
2275
2276         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2277             (dst->dev && !netif_running(dst->dev)))
2278                 return 0;
2279 #ifdef CONFIG_XFRM_SUB_POLICY
2280         if (fl) {
2281                 if (first->origin && !flow_cache_uli_match(first->origin, fl))
2282                         return 0;
2283                 if (first->partner &&
2284                     !xfrm_selector_match(first->partner, fl, family))
2285                         return 0;
2286         }
2287 #endif
2288
2289         last = NULL;
2290
2291         do {
2292                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2293
2294                 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
2295                         return 0;
2296                 if (fl && pol &&
2297                     !security_xfrm_state_pol_flow_match(dst->xfrm, pol, fl))
2298                         return 0;
2299                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2300                         return 0;
2301                 if (xdst->xfrm_genid != dst->xfrm->genid)
2302                         return 0;
2303                 if (xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2304                         return 0;
2305
2306                 if (strict && fl &&
2307                     !(dst->xfrm->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
2308                     !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
2309                         return 0;
2310
2311                 mtu = dst_mtu(dst->child);
2312                 if (xdst->child_mtu_cached != mtu) {
2313                         last = xdst;
2314                         xdst->child_mtu_cached = mtu;
2315                 }
2316
2317                 if (!dst_check(xdst->route, xdst->route_cookie))
2318                         return 0;
2319                 mtu = dst_mtu(xdst->route);
2320                 if (xdst->route_mtu_cached != mtu) {
2321                         last = xdst;
2322                         xdst->route_mtu_cached = mtu;
2323                 }
2324
2325                 dst = dst->child;
2326         } while (dst->xfrm);
2327
2328         if (likely(!last))
2329                 return 1;
2330
2331         mtu = last->child_mtu_cached;
2332         for (;;) {
2333                 dst = &last->u.dst;
2334
2335                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2336                 if (mtu > last->route_mtu_cached)
2337                         mtu = last->route_mtu_cached;
2338                 dst->metrics[RTAX_MTU-1] = mtu;
2339
2340                 if (last == first)
2341                         break;
2342
2343                 last = (struct xfrm_dst *)last->u.dst.next;
2344                 last->child_mtu_cached = mtu;
2345         }
2346
2347         return 1;
2348 }
2349
2350 EXPORT_SYMBOL(xfrm_bundle_ok);
2351
2352 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2353 {
2354         struct net *net;
2355         int err = 0;
2356         if (unlikely(afinfo == NULL))
2357                 return -EINVAL;
2358         if (unlikely(afinfo->family >= NPROTO))
2359                 return -EAFNOSUPPORT;
2360         write_lock_bh(&xfrm_policy_afinfo_lock);
2361         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2362                 err = -ENOBUFS;
2363         else {
2364                 struct dst_ops *dst_ops = afinfo->dst_ops;
2365                 if (likely(dst_ops->kmem_cachep == NULL))
2366                         dst_ops->kmem_cachep = xfrm_dst_cache;
2367                 if (likely(dst_ops->check == NULL))
2368                         dst_ops->check = xfrm_dst_check;
2369                 if (likely(dst_ops->negative_advice == NULL))
2370                         dst_ops->negative_advice = xfrm_negative_advice;
2371                 if (likely(dst_ops->link_failure == NULL))
2372                         dst_ops->link_failure = xfrm_link_failure;
2373                 if (likely(afinfo->garbage_collect == NULL))
2374                         afinfo->garbage_collect = __xfrm_garbage_collect;
2375                 xfrm_policy_afinfo[afinfo->family] = afinfo;
2376         }
2377         write_unlock_bh(&xfrm_policy_afinfo_lock);
2378
2379         rtnl_lock();
2380         for_each_net(net) {
2381                 struct dst_ops *xfrm_dst_ops;
2382
2383                 switch (afinfo->family) {
2384                 case AF_INET:
2385                         xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2386                         break;
2387 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2388                 case AF_INET6:
2389                         xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2390                         break;
2391 #endif
2392                 default:
2393                         BUG();
2394                 }
2395                 *xfrm_dst_ops = *afinfo->dst_ops;
2396         }
2397         rtnl_unlock();
2398
2399         return err;
2400 }
2401 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2402
2403 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2404 {
2405         int err = 0;
2406         if (unlikely(afinfo == NULL))
2407                 return -EINVAL;
2408         if (unlikely(afinfo->family >= NPROTO))
2409                 return -EAFNOSUPPORT;
2410         write_lock_bh(&xfrm_policy_afinfo_lock);
2411         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2412                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2413                         err = -EINVAL;
2414                 else {
2415                         struct dst_ops *dst_ops = afinfo->dst_ops;
2416                         xfrm_policy_afinfo[afinfo->family] = NULL;
2417                         dst_ops->kmem_cachep = NULL;
2418                         dst_ops->check = NULL;
2419                         dst_ops->negative_advice = NULL;
2420                         dst_ops->link_failure = NULL;
2421                         afinfo->garbage_collect = NULL;
2422                 }
2423         }
2424         write_unlock_bh(&xfrm_policy_afinfo_lock);
2425         return err;
2426 }
2427 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2428
2429 static void __net_init xfrm_dst_ops_init(struct net *net)
2430 {
2431         struct xfrm_policy_afinfo *afinfo;
2432
2433         read_lock_bh(&xfrm_policy_afinfo_lock);
2434         afinfo = xfrm_policy_afinfo[AF_INET];
2435         if (afinfo)
2436                 net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2437 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2438         afinfo = xfrm_policy_afinfo[AF_INET6];
2439         if (afinfo)
2440                 net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2441 #endif
2442         read_unlock_bh(&xfrm_policy_afinfo_lock);
2443 }
2444
2445 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
2446 {
2447         struct xfrm_policy_afinfo *afinfo;
2448         if (unlikely(family >= NPROTO))
2449                 return NULL;
2450         read_lock(&xfrm_policy_afinfo_lock);
2451         afinfo = xfrm_policy_afinfo[family];
2452         if (unlikely(!afinfo))
2453                 read_unlock(&xfrm_policy_afinfo_lock);
2454         return afinfo;
2455 }
2456
2457 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
2458 {
2459         read_unlock(&xfrm_policy_afinfo_lock);
2460 }
2461
2462 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2463 {
2464         struct net_device *dev = ptr;
2465
2466         switch (event) {
2467         case NETDEV_DOWN:
2468                 __xfrm_garbage_collect(dev_net(dev));
2469         }
2470         return NOTIFY_DONE;
2471 }
2472
2473 static struct notifier_block xfrm_dev_notifier = {
2474         .notifier_call  = xfrm_dev_event,
2475 };
2476
2477 #ifdef CONFIG_XFRM_STATISTICS
2478 static int __net_init xfrm_statistics_init(struct net *net)
2479 {
2480         int rv;
2481
2482         if (snmp_mib_init((void __percpu **)net->mib.xfrm_statistics,
2483                           sizeof(struct linux_xfrm_mib)) < 0)
2484                 return -ENOMEM;
2485         rv = xfrm_proc_init(net);
2486         if (rv < 0)
2487                 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2488         return rv;
2489 }
2490
2491 static void xfrm_statistics_fini(struct net *net)
2492 {
2493         xfrm_proc_fini(net);
2494         snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2495 }
2496 #else
2497 static int __net_init xfrm_statistics_init(struct net *net)
2498 {
2499         return 0;
2500 }
2501
2502 static void xfrm_statistics_fini(struct net *net)
2503 {
2504 }
2505 #endif
2506
2507 static int __net_init xfrm_policy_init(struct net *net)
2508 {
2509         unsigned int hmask, sz;
2510         int dir;
2511
2512         if (net_eq(net, &init_net))
2513                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2514                                            sizeof(struct xfrm_dst),
2515                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2516                                            NULL);
2517
2518         hmask = 8 - 1;
2519         sz = (hmask+1) * sizeof(struct hlist_head);
2520
2521         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2522         if (!net->xfrm.policy_byidx)
2523                 goto out_byidx;
2524         net->xfrm.policy_idx_hmask = hmask;
2525
2526         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2527                 struct xfrm_policy_hash *htab;
2528
2529                 net->xfrm.policy_count[dir] = 0;
2530                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2531
2532                 htab = &net->xfrm.policy_bydst[dir];
2533                 htab->table = xfrm_hash_alloc(sz);
2534                 if (!htab->table)
2535                         goto out_bydst;
2536                 htab->hmask = hmask;
2537         }
2538
2539         INIT_LIST_HEAD(&net->xfrm.policy_all);
2540         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2541         if (net_eq(net, &init_net))
2542                 register_netdevice_notifier(&xfrm_dev_notifier);
2543         return 0;
2544
2545 out_bydst:
2546         for (dir--; dir >= 0; dir--) {
2547                 struct xfrm_policy_hash *htab;
2548
2549                 htab = &net->xfrm.policy_bydst[dir];
2550                 xfrm_hash_free(htab->table, sz);
2551         }
2552         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2553 out_byidx:
2554         return -ENOMEM;
2555 }
2556
2557 static void xfrm_policy_fini(struct net *net)
2558 {
2559         struct xfrm_audit audit_info;
2560         unsigned int sz;
2561         int dir;
2562
2563         flush_work(&net->xfrm.policy_hash_work);
2564 #ifdef CONFIG_XFRM_SUB_POLICY
2565         audit_info.loginuid = -1;
2566         audit_info.sessionid = -1;
2567         audit_info.secid = 0;
2568         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info);
2569 #endif
2570         audit_info.loginuid = -1;
2571         audit_info.sessionid = -1;
2572         audit_info.secid = 0;
2573         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info);
2574
2575         WARN_ON(!list_empty(&net->xfrm.policy_all));
2576
2577         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2578                 struct xfrm_policy_hash *htab;
2579
2580                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2581
2582                 htab = &net->xfrm.policy_bydst[dir];
2583                 sz = (htab->hmask + 1);
2584                 WARN_ON(!hlist_empty(htab->table));
2585                 xfrm_hash_free(htab->table, sz);
2586         }
2587
2588         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2589         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2590         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2591 }
2592
2593 static int __net_init xfrm_net_init(struct net *net)
2594 {
2595         int rv;
2596
2597         rv = xfrm_statistics_init(net);
2598         if (rv < 0)
2599                 goto out_statistics;
2600         rv = xfrm_state_init(net);
2601         if (rv < 0)
2602                 goto out_state;
2603         rv = xfrm_policy_init(net);
2604         if (rv < 0)
2605                 goto out_policy;
2606         xfrm_dst_ops_init(net);
2607         rv = xfrm_sysctl_init(net);
2608         if (rv < 0)
2609                 goto out_sysctl;
2610         return 0;
2611
2612 out_sysctl:
2613         xfrm_policy_fini(net);
2614 out_policy:
2615         xfrm_state_fini(net);
2616 out_state:
2617         xfrm_statistics_fini(net);
2618 out_statistics:
2619         return rv;
2620 }
2621
2622 static void __net_exit xfrm_net_exit(struct net *net)
2623 {
2624         xfrm_sysctl_fini(net);
2625         xfrm_policy_fini(net);
2626         xfrm_state_fini(net);
2627         xfrm_statistics_fini(net);
2628 }
2629
2630 static struct pernet_operations __net_initdata xfrm_net_ops = {
2631         .init = xfrm_net_init,
2632         .exit = xfrm_net_exit,
2633 };
2634
2635 void __init xfrm_init(void)
2636 {
2637         register_pernet_subsys(&xfrm_net_ops);
2638         xfrm_input_init();
2639 }
2640
2641 #ifdef CONFIG_AUDITSYSCALL
2642 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2643                                          struct audit_buffer *audit_buf)
2644 {
2645         struct xfrm_sec_ctx *ctx = xp->security;
2646         struct xfrm_selector *sel = &xp->selector;
2647
2648         if (ctx)
2649                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2650                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2651
2652         switch(sel->family) {
2653         case AF_INET:
2654                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2655                 if (sel->prefixlen_s != 32)
2656                         audit_log_format(audit_buf, " src_prefixlen=%d",
2657                                          sel->prefixlen_s);
2658                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2659                 if (sel->prefixlen_d != 32)
2660                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2661                                          sel->prefixlen_d);
2662                 break;
2663         case AF_INET6:
2664                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
2665                 if (sel->prefixlen_s != 128)
2666                         audit_log_format(audit_buf, " src_prefixlen=%d",
2667                                          sel->prefixlen_s);
2668                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
2669                 if (sel->prefixlen_d != 128)
2670                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2671                                          sel->prefixlen_d);
2672                 break;
2673         }
2674 }
2675
2676 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2677                            uid_t auid, u32 sessionid, u32 secid)
2678 {
2679         struct audit_buffer *audit_buf;
2680
2681         audit_buf = xfrm_audit_start("SPD-add");
2682         if (audit_buf == NULL)
2683                 return;
2684         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2685         audit_log_format(audit_buf, " res=%u", result);
2686         xfrm_audit_common_policyinfo(xp, audit_buf);
2687         audit_log_end(audit_buf);
2688 }
2689 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
2690
2691 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
2692                               uid_t auid, u32 sessionid, u32 secid)
2693 {
2694         struct audit_buffer *audit_buf;
2695
2696         audit_buf = xfrm_audit_start("SPD-delete");
2697         if (audit_buf == NULL)
2698                 return;
2699         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2700         audit_log_format(audit_buf, " res=%u", result);
2701         xfrm_audit_common_policyinfo(xp, audit_buf);
2702         audit_log_end(audit_buf);
2703 }
2704 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
2705 #endif
2706
2707 #ifdef CONFIG_XFRM_MIGRATE
2708 static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
2709                                        struct xfrm_selector *sel_tgt)
2710 {
2711         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
2712                 if (sel_tgt->family == sel_cmp->family &&
2713                     xfrm_addr_cmp(&sel_tgt->daddr, &sel_cmp->daddr,
2714                                   sel_cmp->family) == 0 &&
2715                     xfrm_addr_cmp(&sel_tgt->saddr, &sel_cmp->saddr,
2716                                   sel_cmp->family) == 0 &&
2717                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
2718                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
2719                         return 1;
2720                 }
2721         } else {
2722                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
2723                         return 1;
2724                 }
2725         }
2726         return 0;
2727 }
2728
2729 static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
2730                                                      u8 dir, u8 type)
2731 {
2732         struct xfrm_policy *pol, *ret = NULL;
2733         struct hlist_node *entry;
2734         struct hlist_head *chain;
2735         u32 priority = ~0U;
2736
2737         read_lock_bh(&xfrm_policy_lock);
2738         chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir);
2739         hlist_for_each_entry(pol, entry, chain, bydst) {
2740                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2741                     pol->type == type) {
2742                         ret = pol;
2743                         priority = ret->priority;
2744                         break;
2745                 }
2746         }
2747         chain = &init_net.xfrm.policy_inexact[dir];
2748         hlist_for_each_entry(pol, entry, chain, bydst) {
2749                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2750                     pol->type == type &&
2751                     pol->priority < priority) {
2752                         ret = pol;
2753                         break;
2754                 }
2755         }
2756
2757         if (ret)
2758                 xfrm_pol_hold(ret);
2759
2760         read_unlock_bh(&xfrm_policy_lock);
2761
2762         return ret;
2763 }
2764
2765 static int migrate_tmpl_match(struct xfrm_migrate *m, struct xfrm_tmpl *t)
2766 {
2767         int match = 0;
2768
2769         if (t->mode == m->mode && t->id.proto == m->proto &&
2770             (m->reqid == 0 || t->reqid == m->reqid)) {
2771                 switch (t->mode) {
2772                 case XFRM_MODE_TUNNEL:
2773                 case XFRM_MODE_BEET:
2774                         if (xfrm_addr_cmp(&t->id.daddr, &m->old_daddr,
2775                                           m->old_family) == 0 &&
2776                             xfrm_addr_cmp(&t->saddr, &m->old_saddr,
2777                                           m->old_family) == 0) {
2778                                 match = 1;
2779                         }
2780                         break;
2781                 case XFRM_MODE_TRANSPORT:
2782                         /* in case of transport mode, template does not store
2783                            any IP addresses, hence we just compare mode and
2784                            protocol */
2785                         match = 1;
2786                         break;
2787                 default:
2788                         break;
2789                 }
2790         }
2791         return match;
2792 }
2793
2794 /* update endpoint address(es) of template(s) */
2795 static int xfrm_policy_migrate(struct xfrm_policy *pol,
2796                                struct xfrm_migrate *m, int num_migrate)
2797 {
2798         struct xfrm_migrate *mp;
2799         int i, j, n = 0;
2800
2801         write_lock_bh(&pol->lock);
2802         if (unlikely(pol->walk.dead)) {
2803                 /* target policy has been deleted */
2804                 write_unlock_bh(&pol->lock);
2805                 return -ENOENT;
2806         }
2807
2808         for (i = 0; i < pol->xfrm_nr; i++) {
2809                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
2810                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
2811                                 continue;
2812                         n++;
2813                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
2814                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
2815                                 continue;
2816                         /* update endpoints */
2817                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
2818                                sizeof(pol->xfrm_vec[i].id.daddr));
2819                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
2820                                sizeof(pol->xfrm_vec[i].saddr));
2821                         pol->xfrm_vec[i].encap_family = mp->new_family;
2822                         /* flush bundles */
2823                         atomic_inc(&pol->genid);
2824                 }
2825         }
2826
2827         write_unlock_bh(&pol->lock);
2828
2829         if (!n)
2830                 return -ENODATA;
2831
2832         return 0;
2833 }
2834
2835 static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
2836 {
2837         int i, j;
2838
2839         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
2840                 return -EINVAL;
2841
2842         for (i = 0; i < num_migrate; i++) {
2843                 if ((xfrm_addr_cmp(&m[i].old_daddr, &m[i].new_daddr,
2844                                    m[i].old_family) == 0) &&
2845                     (xfrm_addr_cmp(&m[i].old_saddr, &m[i].new_saddr,
2846                                    m[i].old_family) == 0))
2847                         return -EINVAL;
2848                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
2849                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
2850                         return -EINVAL;
2851
2852                 /* check if there is any duplicated entry */
2853                 for (j = i + 1; j < num_migrate; j++) {
2854                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
2855                                     sizeof(m[i].old_daddr)) &&
2856                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
2857                                     sizeof(m[i].old_saddr)) &&
2858                             m[i].proto == m[j].proto &&
2859                             m[i].mode == m[j].mode &&
2860                             m[i].reqid == m[j].reqid &&
2861                             m[i].old_family == m[j].old_family)
2862                                 return -EINVAL;
2863                 }
2864         }
2865
2866         return 0;
2867 }
2868
2869 int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
2870                  struct xfrm_migrate *m, int num_migrate,
2871                  struct xfrm_kmaddress *k)
2872 {
2873         int i, err, nx_cur = 0, nx_new = 0;
2874         struct xfrm_policy *pol = NULL;
2875         struct xfrm_state *x, *xc;
2876         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
2877         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
2878         struct xfrm_migrate *mp;
2879
2880         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
2881                 goto out;
2882
2883         /* Stage 1 - find policy */
2884         if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
2885                 err = -ENOENT;
2886                 goto out;
2887         }
2888
2889         /* Stage 2 - find and update state(s) */
2890         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
2891                 if ((x = xfrm_migrate_state_find(mp))) {
2892                         x_cur[nx_cur] = x;
2893                         nx_cur++;
2894                         if ((xc = xfrm_state_migrate(x, mp))) {
2895                                 x_new[nx_new] = xc;
2896                                 nx_new++;
2897                         } else {
2898                                 err = -ENODATA;
2899                                 goto restore_state;
2900                         }
2901                 }
2902         }
2903
2904         /* Stage 3 - update policy */
2905         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
2906                 goto restore_state;
2907
2908         /* Stage 4 - delete old state(s) */
2909         if (nx_cur) {
2910                 xfrm_states_put(x_cur, nx_cur);
2911                 xfrm_states_delete(x_cur, nx_cur);
2912         }
2913
2914         /* Stage 5 - announce */
2915         km_migrate(sel, dir, type, m, num_migrate, k);
2916
2917         xfrm_pol_put(pol);
2918
2919         return 0;
2920 out:
2921         return err;
2922
2923 restore_state:
2924         if (pol)
2925                 xfrm_pol_put(pol);
2926         if (nx_cur)
2927                 xfrm_states_put(x_cur, nx_cur);
2928         if (nx_new)
2929                 xfrm_states_delete(x_new, nx_new);
2930
2931         return err;
2932 }
2933 EXPORT_SYMBOL(xfrm_migrate);
2934 #endif