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Merge branch 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
[mirror_ubuntu-focal-kernel.git] / net / xfrm / xfrm_policy.c
1 /*
2 * xfrm_policy.c
3 *
4 * Changes:
5 * Mitsuru KANDA @USAGI
6 * Kazunori MIYAZAWA @USAGI
7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8 * IPv6 support
9 * Kazunori MIYAZAWA @USAGI
10 * YOSHIFUJI Hideaki
11 * Split up af-specific portion
12 * Derek Atkins <derek@ihtfp.com> Add the post_input processor
13 *
14 */
15
16 #include <linux/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/flow.h>
30 #include <net/xfrm.h>
31 #include <net/ip.h>
32 #ifdef CONFIG_XFRM_STATISTICS
33 #include <net/snmp.h>
34 #endif
35
36 #include "xfrm_hash.h"
37
38 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
39 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
40 #define XFRM_MAX_QUEUE_LEN 100
41
42 DEFINE_MUTEX(xfrm_cfg_mutex);
43 EXPORT_SYMBOL(xfrm_cfg_mutex);
44
45 static DEFINE_SPINLOCK(xfrm_policy_sk_bundle_lock);
46 static struct dst_entry *xfrm_policy_sk_bundles;
47 static DEFINE_RWLOCK(xfrm_policy_lock);
48
49 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
50 static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
51 __read_mostly;
52
53 static struct kmem_cache *xfrm_dst_cache __read_mostly;
54
55 static void xfrm_init_pmtu(struct dst_entry *dst);
56 static int stale_bundle(struct dst_entry *dst);
57 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
58 static void xfrm_policy_queue_process(unsigned long arg);
59
60 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
61 int dir);
62
63 static inline bool
64 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
65 {
66 const struct flowi4 *fl4 = &fl->u.ip4;
67
68 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
69 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
70 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
71 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
72 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
73 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
74 }
75
76 static inline bool
77 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
78 {
79 const struct flowi6 *fl6 = &fl->u.ip6;
80
81 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
82 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
83 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
84 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
85 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
86 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
87 }
88
89 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
90 unsigned short family)
91 {
92 switch (family) {
93 case AF_INET:
94 return __xfrm4_selector_match(sel, fl);
95 case AF_INET6:
96 return __xfrm6_selector_match(sel, fl);
97 }
98 return false;
99 }
100
101 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
102 {
103 struct xfrm_policy_afinfo *afinfo;
104
105 if (unlikely(family >= NPROTO))
106 return NULL;
107 rcu_read_lock();
108 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
109 if (unlikely(!afinfo))
110 rcu_read_unlock();
111 return afinfo;
112 }
113
114 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
115 {
116 rcu_read_unlock();
117 }
118
119 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
120 const xfrm_address_t *saddr,
121 const xfrm_address_t *daddr,
122 int family)
123 {
124 struct xfrm_policy_afinfo *afinfo;
125 struct dst_entry *dst;
126
127 afinfo = xfrm_policy_get_afinfo(family);
128 if (unlikely(afinfo == NULL))
129 return ERR_PTR(-EAFNOSUPPORT);
130
131 dst = afinfo->dst_lookup(net, tos, saddr, daddr);
132
133 xfrm_policy_put_afinfo(afinfo);
134
135 return dst;
136 }
137
138 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
139 xfrm_address_t *prev_saddr,
140 xfrm_address_t *prev_daddr,
141 int family)
142 {
143 struct net *net = xs_net(x);
144 xfrm_address_t *saddr = &x->props.saddr;
145 xfrm_address_t *daddr = &x->id.daddr;
146 struct dst_entry *dst;
147
148 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
149 saddr = x->coaddr;
150 daddr = prev_daddr;
151 }
152 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
153 saddr = prev_saddr;
154 daddr = x->coaddr;
155 }
156
157 dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
158
159 if (!IS_ERR(dst)) {
160 if (prev_saddr != saddr)
161 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
162 if (prev_daddr != daddr)
163 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
164 }
165
166 return dst;
167 }
168
169 static inline unsigned long make_jiffies(long secs)
170 {
171 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
172 return MAX_SCHEDULE_TIMEOUT-1;
173 else
174 return secs*HZ;
175 }
176
177 static void xfrm_policy_timer(unsigned long data)
178 {
179 struct xfrm_policy *xp = (struct xfrm_policy*)data;
180 unsigned long now = get_seconds();
181 long next = LONG_MAX;
182 int warn = 0;
183 int dir;
184
185 read_lock(&xp->lock);
186
187 if (unlikely(xp->walk.dead))
188 goto out;
189
190 dir = xfrm_policy_id2dir(xp->index);
191
192 if (xp->lft.hard_add_expires_seconds) {
193 long tmo = xp->lft.hard_add_expires_seconds +
194 xp->curlft.add_time - now;
195 if (tmo <= 0)
196 goto expired;
197 if (tmo < next)
198 next = tmo;
199 }
200 if (xp->lft.hard_use_expires_seconds) {
201 long tmo = xp->lft.hard_use_expires_seconds +
202 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
203 if (tmo <= 0)
204 goto expired;
205 if (tmo < next)
206 next = tmo;
207 }
208 if (xp->lft.soft_add_expires_seconds) {
209 long tmo = xp->lft.soft_add_expires_seconds +
210 xp->curlft.add_time - now;
211 if (tmo <= 0) {
212 warn = 1;
213 tmo = XFRM_KM_TIMEOUT;
214 }
215 if (tmo < next)
216 next = tmo;
217 }
218 if (xp->lft.soft_use_expires_seconds) {
219 long tmo = xp->lft.soft_use_expires_seconds +
220 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
221 if (tmo <= 0) {
222 warn = 1;
223 tmo = XFRM_KM_TIMEOUT;
224 }
225 if (tmo < next)
226 next = tmo;
227 }
228
229 if (warn)
230 km_policy_expired(xp, dir, 0, 0);
231 if (next != LONG_MAX &&
232 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
233 xfrm_pol_hold(xp);
234
235 out:
236 read_unlock(&xp->lock);
237 xfrm_pol_put(xp);
238 return;
239
240 expired:
241 read_unlock(&xp->lock);
242 if (!xfrm_policy_delete(xp, dir))
243 km_policy_expired(xp, dir, 1, 0);
244 xfrm_pol_put(xp);
245 }
246
247 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
248 {
249 struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
250
251 if (unlikely(pol->walk.dead))
252 flo = NULL;
253 else
254 xfrm_pol_hold(pol);
255
256 return flo;
257 }
258
259 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
260 {
261 struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
262
263 return !pol->walk.dead;
264 }
265
266 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
267 {
268 xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
269 }
270
271 static const struct flow_cache_ops xfrm_policy_fc_ops = {
272 .get = xfrm_policy_flo_get,
273 .check = xfrm_policy_flo_check,
274 .delete = xfrm_policy_flo_delete,
275 };
276
277 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
278 * SPD calls.
279 */
280
281 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
282 {
283 struct xfrm_policy *policy;
284
285 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
286
287 if (policy) {
288 write_pnet(&policy->xp_net, net);
289 INIT_LIST_HEAD(&policy->walk.all);
290 INIT_HLIST_NODE(&policy->bydst);
291 INIT_HLIST_NODE(&policy->byidx);
292 rwlock_init(&policy->lock);
293 atomic_set(&policy->refcnt, 1);
294 skb_queue_head_init(&policy->polq.hold_queue);
295 setup_timer(&policy->timer, xfrm_policy_timer,
296 (unsigned long)policy);
297 setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
298 (unsigned long)policy);
299 policy->flo.ops = &xfrm_policy_fc_ops;
300 }
301 return policy;
302 }
303 EXPORT_SYMBOL(xfrm_policy_alloc);
304
305 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
306
307 void xfrm_policy_destroy(struct xfrm_policy *policy)
308 {
309 BUG_ON(!policy->walk.dead);
310
311 if (del_timer(&policy->timer))
312 BUG();
313
314 security_xfrm_policy_free(policy->security);
315 kfree(policy);
316 }
317 EXPORT_SYMBOL(xfrm_policy_destroy);
318
319 static void xfrm_queue_purge(struct sk_buff_head *list)
320 {
321 struct sk_buff *skb;
322
323 while ((skb = skb_dequeue(list)) != NULL) {
324 dev_put(skb->dev);
325 kfree_skb(skb);
326 }
327 }
328
329 /* Rule must be locked. Release descentant resources, announce
330 * entry dead. The rule must be unlinked from lists to the moment.
331 */
332
333 static void xfrm_policy_kill(struct xfrm_policy *policy)
334 {
335 policy->walk.dead = 1;
336
337 atomic_inc(&policy->genid);
338
339 del_timer(&policy->polq.hold_timer);
340 xfrm_queue_purge(&policy->polq.hold_queue);
341
342 if (del_timer(&policy->timer))
343 xfrm_pol_put(policy);
344
345 xfrm_pol_put(policy);
346 }
347
348 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
349
350 static inline unsigned int idx_hash(struct net *net, u32 index)
351 {
352 return __idx_hash(index, net->xfrm.policy_idx_hmask);
353 }
354
355 static struct hlist_head *policy_hash_bysel(struct net *net,
356 const struct xfrm_selector *sel,
357 unsigned short family, int dir)
358 {
359 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
360 unsigned int hash = __sel_hash(sel, family, hmask);
361
362 return (hash == hmask + 1 ?
363 &net->xfrm.policy_inexact[dir] :
364 net->xfrm.policy_bydst[dir].table + hash);
365 }
366
367 static struct hlist_head *policy_hash_direct(struct net *net,
368 const xfrm_address_t *daddr,
369 const xfrm_address_t *saddr,
370 unsigned short family, int dir)
371 {
372 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
373 unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
374
375 return net->xfrm.policy_bydst[dir].table + hash;
376 }
377
378 static void xfrm_dst_hash_transfer(struct hlist_head *list,
379 struct hlist_head *ndsttable,
380 unsigned int nhashmask)
381 {
382 struct hlist_node *entry, *tmp, *entry0 = NULL;
383 struct xfrm_policy *pol;
384 unsigned int h0 = 0;
385
386 redo:
387 hlist_for_each_entry_safe(pol, entry, tmp, list, bydst) {
388 unsigned int h;
389
390 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
391 pol->family, nhashmask);
392 if (!entry0) {
393 hlist_del(entry);
394 hlist_add_head(&pol->bydst, ndsttable+h);
395 h0 = h;
396 } else {
397 if (h != h0)
398 continue;
399 hlist_del(entry);
400 hlist_add_after(entry0, &pol->bydst);
401 }
402 entry0 = entry;
403 }
404 if (!hlist_empty(list)) {
405 entry0 = NULL;
406 goto redo;
407 }
408 }
409
410 static void xfrm_idx_hash_transfer(struct hlist_head *list,
411 struct hlist_head *nidxtable,
412 unsigned int nhashmask)
413 {
414 struct hlist_node *entry, *tmp;
415 struct xfrm_policy *pol;
416
417 hlist_for_each_entry_safe(pol, entry, tmp, list, byidx) {
418 unsigned int h;
419
420 h = __idx_hash(pol->index, nhashmask);
421 hlist_add_head(&pol->byidx, nidxtable+h);
422 }
423 }
424
425 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
426 {
427 return ((old_hmask + 1) << 1) - 1;
428 }
429
430 static void xfrm_bydst_resize(struct net *net, int dir)
431 {
432 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
433 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
434 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
435 struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
436 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
437 int i;
438
439 if (!ndst)
440 return;
441
442 write_lock_bh(&xfrm_policy_lock);
443
444 for (i = hmask; i >= 0; i--)
445 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
446
447 net->xfrm.policy_bydst[dir].table = ndst;
448 net->xfrm.policy_bydst[dir].hmask = nhashmask;
449
450 write_unlock_bh(&xfrm_policy_lock);
451
452 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
453 }
454
455 static void xfrm_byidx_resize(struct net *net, int total)
456 {
457 unsigned int hmask = net->xfrm.policy_idx_hmask;
458 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
459 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
460 struct hlist_head *oidx = net->xfrm.policy_byidx;
461 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
462 int i;
463
464 if (!nidx)
465 return;
466
467 write_lock_bh(&xfrm_policy_lock);
468
469 for (i = hmask; i >= 0; i--)
470 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
471
472 net->xfrm.policy_byidx = nidx;
473 net->xfrm.policy_idx_hmask = nhashmask;
474
475 write_unlock_bh(&xfrm_policy_lock);
476
477 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
478 }
479
480 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
481 {
482 unsigned int cnt = net->xfrm.policy_count[dir];
483 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
484
485 if (total)
486 *total += cnt;
487
488 if ((hmask + 1) < xfrm_policy_hashmax &&
489 cnt > hmask)
490 return 1;
491
492 return 0;
493 }
494
495 static inline int xfrm_byidx_should_resize(struct net *net, int total)
496 {
497 unsigned int hmask = net->xfrm.policy_idx_hmask;
498
499 if ((hmask + 1) < xfrm_policy_hashmax &&
500 total > hmask)
501 return 1;
502
503 return 0;
504 }
505
506 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
507 {
508 read_lock_bh(&xfrm_policy_lock);
509 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
510 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
511 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
512 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
513 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
514 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
515 si->spdhcnt = net->xfrm.policy_idx_hmask;
516 si->spdhmcnt = xfrm_policy_hashmax;
517 read_unlock_bh(&xfrm_policy_lock);
518 }
519 EXPORT_SYMBOL(xfrm_spd_getinfo);
520
521 static DEFINE_MUTEX(hash_resize_mutex);
522 static void xfrm_hash_resize(struct work_struct *work)
523 {
524 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
525 int dir, total;
526
527 mutex_lock(&hash_resize_mutex);
528
529 total = 0;
530 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
531 if (xfrm_bydst_should_resize(net, dir, &total))
532 xfrm_bydst_resize(net, dir);
533 }
534 if (xfrm_byidx_should_resize(net, total))
535 xfrm_byidx_resize(net, total);
536
537 mutex_unlock(&hash_resize_mutex);
538 }
539
540 /* Generate new index... KAME seems to generate them ordered by cost
541 * of an absolute inpredictability of ordering of rules. This will not pass. */
542 static u32 xfrm_gen_index(struct net *net, int dir)
543 {
544 static u32 idx_generator;
545
546 for (;;) {
547 struct hlist_node *entry;
548 struct hlist_head *list;
549 struct xfrm_policy *p;
550 u32 idx;
551 int found;
552
553 idx = (idx_generator | dir);
554 idx_generator += 8;
555 if (idx == 0)
556 idx = 8;
557 list = net->xfrm.policy_byidx + idx_hash(net, idx);
558 found = 0;
559 hlist_for_each_entry(p, entry, list, byidx) {
560 if (p->index == idx) {
561 found = 1;
562 break;
563 }
564 }
565 if (!found)
566 return idx;
567 }
568 }
569
570 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
571 {
572 u32 *p1 = (u32 *) s1;
573 u32 *p2 = (u32 *) s2;
574 int len = sizeof(struct xfrm_selector) / sizeof(u32);
575 int i;
576
577 for (i = 0; i < len; i++) {
578 if (p1[i] != p2[i])
579 return 1;
580 }
581
582 return 0;
583 }
584
585 static void xfrm_policy_requeue(struct xfrm_policy *old,
586 struct xfrm_policy *new)
587 {
588 struct xfrm_policy_queue *pq = &old->polq;
589 struct sk_buff_head list;
590
591 __skb_queue_head_init(&list);
592
593 spin_lock_bh(&pq->hold_queue.lock);
594 skb_queue_splice_init(&pq->hold_queue, &list);
595 del_timer(&pq->hold_timer);
596 spin_unlock_bh(&pq->hold_queue.lock);
597
598 if (skb_queue_empty(&list))
599 return;
600
601 pq = &new->polq;
602
603 spin_lock_bh(&pq->hold_queue.lock);
604 skb_queue_splice(&list, &pq->hold_queue);
605 pq->timeout = XFRM_QUEUE_TMO_MIN;
606 mod_timer(&pq->hold_timer, jiffies);
607 spin_unlock_bh(&pq->hold_queue.lock);
608 }
609
610 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
611 struct xfrm_policy *pol)
612 {
613 u32 mark = policy->mark.v & policy->mark.m;
614
615 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
616 return true;
617
618 if ((mark & pol->mark.m) == pol->mark.v &&
619 policy->priority == pol->priority)
620 return true;
621
622 return false;
623 }
624
625 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
626 {
627 struct net *net = xp_net(policy);
628 struct xfrm_policy *pol;
629 struct xfrm_policy *delpol;
630 struct hlist_head *chain;
631 struct hlist_node *entry, *newpos;
632
633 write_lock_bh(&xfrm_policy_lock);
634 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
635 delpol = NULL;
636 newpos = NULL;
637 hlist_for_each_entry(pol, entry, chain, bydst) {
638 if (pol->type == policy->type &&
639 !selector_cmp(&pol->selector, &policy->selector) &&
640 xfrm_policy_mark_match(policy, pol) &&
641 xfrm_sec_ctx_match(pol->security, policy->security) &&
642 !WARN_ON(delpol)) {
643 if (excl) {
644 write_unlock_bh(&xfrm_policy_lock);
645 return -EEXIST;
646 }
647 delpol = pol;
648 if (policy->priority > pol->priority)
649 continue;
650 } else if (policy->priority >= pol->priority) {
651 newpos = &pol->bydst;
652 continue;
653 }
654 if (delpol)
655 break;
656 }
657 if (newpos)
658 hlist_add_after(newpos, &policy->bydst);
659 else
660 hlist_add_head(&policy->bydst, chain);
661 xfrm_pol_hold(policy);
662 net->xfrm.policy_count[dir]++;
663 atomic_inc(&flow_cache_genid);
664 rt_genid_bump(net);
665 if (delpol) {
666 xfrm_policy_requeue(delpol, policy);
667 __xfrm_policy_unlink(delpol, dir);
668 }
669 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir);
670 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
671 policy->curlft.add_time = get_seconds();
672 policy->curlft.use_time = 0;
673 if (!mod_timer(&policy->timer, jiffies + HZ))
674 xfrm_pol_hold(policy);
675 list_add(&policy->walk.all, &net->xfrm.policy_all);
676 write_unlock_bh(&xfrm_policy_lock);
677
678 if (delpol)
679 xfrm_policy_kill(delpol);
680 else if (xfrm_bydst_should_resize(net, dir, NULL))
681 schedule_work(&net->xfrm.policy_hash_work);
682
683 return 0;
684 }
685 EXPORT_SYMBOL(xfrm_policy_insert);
686
687 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
688 int dir, struct xfrm_selector *sel,
689 struct xfrm_sec_ctx *ctx, int delete,
690 int *err)
691 {
692 struct xfrm_policy *pol, *ret;
693 struct hlist_head *chain;
694 struct hlist_node *entry;
695
696 *err = 0;
697 write_lock_bh(&xfrm_policy_lock);
698 chain = policy_hash_bysel(net, sel, sel->family, dir);
699 ret = NULL;
700 hlist_for_each_entry(pol, entry, chain, bydst) {
701 if (pol->type == type &&
702 (mark & pol->mark.m) == pol->mark.v &&
703 !selector_cmp(sel, &pol->selector) &&
704 xfrm_sec_ctx_match(ctx, pol->security)) {
705 xfrm_pol_hold(pol);
706 if (delete) {
707 *err = security_xfrm_policy_delete(
708 pol->security);
709 if (*err) {
710 write_unlock_bh(&xfrm_policy_lock);
711 return pol;
712 }
713 __xfrm_policy_unlink(pol, dir);
714 }
715 ret = pol;
716 break;
717 }
718 }
719 write_unlock_bh(&xfrm_policy_lock);
720
721 if (ret && delete)
722 xfrm_policy_kill(ret);
723 return ret;
724 }
725 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
726
727 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
728 int dir, u32 id, int delete, int *err)
729 {
730 struct xfrm_policy *pol, *ret;
731 struct hlist_head *chain;
732 struct hlist_node *entry;
733
734 *err = -ENOENT;
735 if (xfrm_policy_id2dir(id) != dir)
736 return NULL;
737
738 *err = 0;
739 write_lock_bh(&xfrm_policy_lock);
740 chain = net->xfrm.policy_byidx + idx_hash(net, id);
741 ret = NULL;
742 hlist_for_each_entry(pol, entry, chain, byidx) {
743 if (pol->type == type && pol->index == id &&
744 (mark & pol->mark.m) == pol->mark.v) {
745 xfrm_pol_hold(pol);
746 if (delete) {
747 *err = security_xfrm_policy_delete(
748 pol->security);
749 if (*err) {
750 write_unlock_bh(&xfrm_policy_lock);
751 return pol;
752 }
753 __xfrm_policy_unlink(pol, dir);
754 }
755 ret = pol;
756 break;
757 }
758 }
759 write_unlock_bh(&xfrm_policy_lock);
760
761 if (ret && delete)
762 xfrm_policy_kill(ret);
763 return ret;
764 }
765 EXPORT_SYMBOL(xfrm_policy_byid);
766
767 #ifdef CONFIG_SECURITY_NETWORK_XFRM
768 static inline int
769 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
770 {
771 int dir, err = 0;
772
773 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
774 struct xfrm_policy *pol;
775 struct hlist_node *entry;
776 int i;
777
778 hlist_for_each_entry(pol, entry,
779 &net->xfrm.policy_inexact[dir], bydst) {
780 if (pol->type != type)
781 continue;
782 err = security_xfrm_policy_delete(pol->security);
783 if (err) {
784 xfrm_audit_policy_delete(pol, 0,
785 audit_info->loginuid,
786 audit_info->sessionid,
787 audit_info->secid);
788 return err;
789 }
790 }
791 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
792 hlist_for_each_entry(pol, entry,
793 net->xfrm.policy_bydst[dir].table + i,
794 bydst) {
795 if (pol->type != type)
796 continue;
797 err = security_xfrm_policy_delete(
798 pol->security);
799 if (err) {
800 xfrm_audit_policy_delete(pol, 0,
801 audit_info->loginuid,
802 audit_info->sessionid,
803 audit_info->secid);
804 return err;
805 }
806 }
807 }
808 }
809 return err;
810 }
811 #else
812 static inline int
813 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
814 {
815 return 0;
816 }
817 #endif
818
819 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info)
820 {
821 int dir, err = 0, cnt = 0;
822
823 write_lock_bh(&xfrm_policy_lock);
824
825 err = xfrm_policy_flush_secctx_check(net, type, audit_info);
826 if (err)
827 goto out;
828
829 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
830 struct xfrm_policy *pol;
831 struct hlist_node *entry;
832 int i;
833
834 again1:
835 hlist_for_each_entry(pol, entry,
836 &net->xfrm.policy_inexact[dir], bydst) {
837 if (pol->type != type)
838 continue;
839 __xfrm_policy_unlink(pol, dir);
840 write_unlock_bh(&xfrm_policy_lock);
841 cnt++;
842
843 xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
844 audit_info->sessionid,
845 audit_info->secid);
846
847 xfrm_policy_kill(pol);
848
849 write_lock_bh(&xfrm_policy_lock);
850 goto again1;
851 }
852
853 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
854 again2:
855 hlist_for_each_entry(pol, entry,
856 net->xfrm.policy_bydst[dir].table + i,
857 bydst) {
858 if (pol->type != type)
859 continue;
860 __xfrm_policy_unlink(pol, dir);
861 write_unlock_bh(&xfrm_policy_lock);
862 cnt++;
863
864 xfrm_audit_policy_delete(pol, 1,
865 audit_info->loginuid,
866 audit_info->sessionid,
867 audit_info->secid);
868 xfrm_policy_kill(pol);
869
870 write_lock_bh(&xfrm_policy_lock);
871 goto again2;
872 }
873 }
874
875 }
876 if (!cnt)
877 err = -ESRCH;
878 out:
879 write_unlock_bh(&xfrm_policy_lock);
880 return err;
881 }
882 EXPORT_SYMBOL(xfrm_policy_flush);
883
884 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
885 int (*func)(struct xfrm_policy *, int, int, void*),
886 void *data)
887 {
888 struct xfrm_policy *pol;
889 struct xfrm_policy_walk_entry *x;
890 int error = 0;
891
892 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
893 walk->type != XFRM_POLICY_TYPE_ANY)
894 return -EINVAL;
895
896 if (list_empty(&walk->walk.all) && walk->seq != 0)
897 return 0;
898
899 write_lock_bh(&xfrm_policy_lock);
900 if (list_empty(&walk->walk.all))
901 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
902 else
903 x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
904 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
905 if (x->dead)
906 continue;
907 pol = container_of(x, struct xfrm_policy, walk);
908 if (walk->type != XFRM_POLICY_TYPE_ANY &&
909 walk->type != pol->type)
910 continue;
911 error = func(pol, xfrm_policy_id2dir(pol->index),
912 walk->seq, data);
913 if (error) {
914 list_move_tail(&walk->walk.all, &x->all);
915 goto out;
916 }
917 walk->seq++;
918 }
919 if (walk->seq == 0) {
920 error = -ENOENT;
921 goto out;
922 }
923 list_del_init(&walk->walk.all);
924 out:
925 write_unlock_bh(&xfrm_policy_lock);
926 return error;
927 }
928 EXPORT_SYMBOL(xfrm_policy_walk);
929
930 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
931 {
932 INIT_LIST_HEAD(&walk->walk.all);
933 walk->walk.dead = 1;
934 walk->type = type;
935 walk->seq = 0;
936 }
937 EXPORT_SYMBOL(xfrm_policy_walk_init);
938
939 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk)
940 {
941 if (list_empty(&walk->walk.all))
942 return;
943
944 write_lock_bh(&xfrm_policy_lock);
945 list_del(&walk->walk.all);
946 write_unlock_bh(&xfrm_policy_lock);
947 }
948 EXPORT_SYMBOL(xfrm_policy_walk_done);
949
950 /*
951 * Find policy to apply to this flow.
952 *
953 * Returns 0 if policy found, else an -errno.
954 */
955 static int xfrm_policy_match(const struct xfrm_policy *pol,
956 const struct flowi *fl,
957 u8 type, u16 family, int dir)
958 {
959 const struct xfrm_selector *sel = &pol->selector;
960 int ret = -ESRCH;
961 bool match;
962
963 if (pol->family != family ||
964 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
965 pol->type != type)
966 return ret;
967
968 match = xfrm_selector_match(sel, fl, family);
969 if (match)
970 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
971 dir);
972
973 return ret;
974 }
975
976 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
977 const struct flowi *fl,
978 u16 family, u8 dir)
979 {
980 int err;
981 struct xfrm_policy *pol, *ret;
982 const xfrm_address_t *daddr, *saddr;
983 struct hlist_node *entry;
984 struct hlist_head *chain;
985 u32 priority = ~0U;
986
987 daddr = xfrm_flowi_daddr(fl, family);
988 saddr = xfrm_flowi_saddr(fl, family);
989 if (unlikely(!daddr || !saddr))
990 return NULL;
991
992 read_lock_bh(&xfrm_policy_lock);
993 chain = policy_hash_direct(net, daddr, saddr, family, dir);
994 ret = NULL;
995 hlist_for_each_entry(pol, entry, chain, bydst) {
996 err = xfrm_policy_match(pol, fl, type, family, dir);
997 if (err) {
998 if (err == -ESRCH)
999 continue;
1000 else {
1001 ret = ERR_PTR(err);
1002 goto fail;
1003 }
1004 } else {
1005 ret = pol;
1006 priority = ret->priority;
1007 break;
1008 }
1009 }
1010 chain = &net->xfrm.policy_inexact[dir];
1011 hlist_for_each_entry(pol, entry, chain, bydst) {
1012 err = xfrm_policy_match(pol, fl, type, family, dir);
1013 if (err) {
1014 if (err == -ESRCH)
1015 continue;
1016 else {
1017 ret = ERR_PTR(err);
1018 goto fail;
1019 }
1020 } else if (pol->priority < priority) {
1021 ret = pol;
1022 break;
1023 }
1024 }
1025 if (ret)
1026 xfrm_pol_hold(ret);
1027 fail:
1028 read_unlock_bh(&xfrm_policy_lock);
1029
1030 return ret;
1031 }
1032
1033 static struct xfrm_policy *
1034 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1035 {
1036 #ifdef CONFIG_XFRM_SUB_POLICY
1037 struct xfrm_policy *pol;
1038
1039 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1040 if (pol != NULL)
1041 return pol;
1042 #endif
1043 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1044 }
1045
1046 static struct flow_cache_object *
1047 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1048 u8 dir, struct flow_cache_object *old_obj, void *ctx)
1049 {
1050 struct xfrm_policy *pol;
1051
1052 if (old_obj)
1053 xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1054
1055 pol = __xfrm_policy_lookup(net, fl, family, dir);
1056 if (IS_ERR_OR_NULL(pol))
1057 return ERR_CAST(pol);
1058
1059 /* Resolver returns two references:
1060 * one for cache and one for caller of flow_cache_lookup() */
1061 xfrm_pol_hold(pol);
1062
1063 return &pol->flo;
1064 }
1065
1066 static inline int policy_to_flow_dir(int dir)
1067 {
1068 if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1069 XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1070 XFRM_POLICY_FWD == FLOW_DIR_FWD)
1071 return dir;
1072 switch (dir) {
1073 default:
1074 case XFRM_POLICY_IN:
1075 return FLOW_DIR_IN;
1076 case XFRM_POLICY_OUT:
1077 return FLOW_DIR_OUT;
1078 case XFRM_POLICY_FWD:
1079 return FLOW_DIR_FWD;
1080 }
1081 }
1082
1083 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
1084 const struct flowi *fl)
1085 {
1086 struct xfrm_policy *pol;
1087
1088 read_lock_bh(&xfrm_policy_lock);
1089 if ((pol = sk->sk_policy[dir]) != NULL) {
1090 bool match = xfrm_selector_match(&pol->selector, fl,
1091 sk->sk_family);
1092 int err = 0;
1093
1094 if (match) {
1095 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1096 pol = NULL;
1097 goto out;
1098 }
1099 err = security_xfrm_policy_lookup(pol->security,
1100 fl->flowi_secid,
1101 policy_to_flow_dir(dir));
1102 if (!err)
1103 xfrm_pol_hold(pol);
1104 else if (err == -ESRCH)
1105 pol = NULL;
1106 else
1107 pol = ERR_PTR(err);
1108 } else
1109 pol = NULL;
1110 }
1111 out:
1112 read_unlock_bh(&xfrm_policy_lock);
1113 return pol;
1114 }
1115
1116 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1117 {
1118 struct net *net = xp_net(pol);
1119 struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1120 pol->family, dir);
1121
1122 list_add(&pol->walk.all, &net->xfrm.policy_all);
1123 hlist_add_head(&pol->bydst, chain);
1124 hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1125 net->xfrm.policy_count[dir]++;
1126 xfrm_pol_hold(pol);
1127
1128 if (xfrm_bydst_should_resize(net, dir, NULL))
1129 schedule_work(&net->xfrm.policy_hash_work);
1130 }
1131
1132 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1133 int dir)
1134 {
1135 struct net *net = xp_net(pol);
1136
1137 if (hlist_unhashed(&pol->bydst))
1138 return NULL;
1139
1140 hlist_del(&pol->bydst);
1141 hlist_del(&pol->byidx);
1142 list_del(&pol->walk.all);
1143 net->xfrm.policy_count[dir]--;
1144
1145 return pol;
1146 }
1147
1148 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1149 {
1150 write_lock_bh(&xfrm_policy_lock);
1151 pol = __xfrm_policy_unlink(pol, dir);
1152 write_unlock_bh(&xfrm_policy_lock);
1153 if (pol) {
1154 xfrm_policy_kill(pol);
1155 return 0;
1156 }
1157 return -ENOENT;
1158 }
1159 EXPORT_SYMBOL(xfrm_policy_delete);
1160
1161 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1162 {
1163 struct net *net = xp_net(pol);
1164 struct xfrm_policy *old_pol;
1165
1166 #ifdef CONFIG_XFRM_SUB_POLICY
1167 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1168 return -EINVAL;
1169 #endif
1170
1171 write_lock_bh(&xfrm_policy_lock);
1172 old_pol = sk->sk_policy[dir];
1173 sk->sk_policy[dir] = pol;
1174 if (pol) {
1175 pol->curlft.add_time = get_seconds();
1176 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir);
1177 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1178 }
1179 if (old_pol) {
1180 if (pol)
1181 xfrm_policy_requeue(old_pol, pol);
1182
1183 /* Unlinking succeeds always. This is the only function
1184 * allowed to delete or replace socket policy.
1185 */
1186 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1187 }
1188 write_unlock_bh(&xfrm_policy_lock);
1189
1190 if (old_pol) {
1191 xfrm_policy_kill(old_pol);
1192 }
1193 return 0;
1194 }
1195
1196 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1197 {
1198 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1199
1200 if (newp) {
1201 newp->selector = old->selector;
1202 if (security_xfrm_policy_clone(old->security,
1203 &newp->security)) {
1204 kfree(newp);
1205 return NULL; /* ENOMEM */
1206 }
1207 newp->lft = old->lft;
1208 newp->curlft = old->curlft;
1209 newp->mark = old->mark;
1210 newp->action = old->action;
1211 newp->flags = old->flags;
1212 newp->xfrm_nr = old->xfrm_nr;
1213 newp->index = old->index;
1214 newp->type = old->type;
1215 memcpy(newp->xfrm_vec, old->xfrm_vec,
1216 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1217 write_lock_bh(&xfrm_policy_lock);
1218 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1219 write_unlock_bh(&xfrm_policy_lock);
1220 xfrm_pol_put(newp);
1221 }
1222 return newp;
1223 }
1224
1225 int __xfrm_sk_clone_policy(struct sock *sk)
1226 {
1227 struct xfrm_policy *p0 = sk->sk_policy[0],
1228 *p1 = sk->sk_policy[1];
1229
1230 sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1231 if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1232 return -ENOMEM;
1233 if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1234 return -ENOMEM;
1235 return 0;
1236 }
1237
1238 static int
1239 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1240 unsigned short family)
1241 {
1242 int err;
1243 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1244
1245 if (unlikely(afinfo == NULL))
1246 return -EINVAL;
1247 err = afinfo->get_saddr(net, local, remote);
1248 xfrm_policy_put_afinfo(afinfo);
1249 return err;
1250 }
1251
1252 /* Resolve list of templates for the flow, given policy. */
1253
1254 static int
1255 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1256 struct xfrm_state **xfrm, unsigned short family)
1257 {
1258 struct net *net = xp_net(policy);
1259 int nx;
1260 int i, error;
1261 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1262 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1263 xfrm_address_t tmp;
1264
1265 for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1266 struct xfrm_state *x;
1267 xfrm_address_t *remote = daddr;
1268 xfrm_address_t *local = saddr;
1269 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1270
1271 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1272 tmpl->mode == XFRM_MODE_BEET) {
1273 remote = &tmpl->id.daddr;
1274 local = &tmpl->saddr;
1275 if (xfrm_addr_any(local, tmpl->encap_family)) {
1276 error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family);
1277 if (error)
1278 goto fail;
1279 local = &tmp;
1280 }
1281 }
1282
1283 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1284
1285 if (x && x->km.state == XFRM_STATE_VALID) {
1286 xfrm[nx++] = x;
1287 daddr = remote;
1288 saddr = local;
1289 continue;
1290 }
1291 if (x) {
1292 error = (x->km.state == XFRM_STATE_ERROR ?
1293 -EINVAL : -EAGAIN);
1294 xfrm_state_put(x);
1295 }
1296 else if (error == -ESRCH)
1297 error = -EAGAIN;
1298
1299 if (!tmpl->optional)
1300 goto fail;
1301 }
1302 return nx;
1303
1304 fail:
1305 for (nx--; nx>=0; nx--)
1306 xfrm_state_put(xfrm[nx]);
1307 return error;
1308 }
1309
1310 static int
1311 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1312 struct xfrm_state **xfrm, unsigned short family)
1313 {
1314 struct xfrm_state *tp[XFRM_MAX_DEPTH];
1315 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1316 int cnx = 0;
1317 int error;
1318 int ret;
1319 int i;
1320
1321 for (i = 0; i < npols; i++) {
1322 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1323 error = -ENOBUFS;
1324 goto fail;
1325 }
1326
1327 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1328 if (ret < 0) {
1329 error = ret;
1330 goto fail;
1331 } else
1332 cnx += ret;
1333 }
1334
1335 /* found states are sorted for outbound processing */
1336 if (npols > 1)
1337 xfrm_state_sort(xfrm, tpp, cnx, family);
1338
1339 return cnx;
1340
1341 fail:
1342 for (cnx--; cnx>=0; cnx--)
1343 xfrm_state_put(tpp[cnx]);
1344 return error;
1345
1346 }
1347
1348 /* Check that the bundle accepts the flow and its components are
1349 * still valid.
1350 */
1351
1352 static inline int xfrm_get_tos(const struct flowi *fl, int family)
1353 {
1354 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1355 int tos;
1356
1357 if (!afinfo)
1358 return -EINVAL;
1359
1360 tos = afinfo->get_tos(fl);
1361
1362 xfrm_policy_put_afinfo(afinfo);
1363
1364 return tos;
1365 }
1366
1367 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1368 {
1369 struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1370 struct dst_entry *dst = &xdst->u.dst;
1371
1372 if (xdst->route == NULL) {
1373 /* Dummy bundle - if it has xfrms we were not
1374 * able to build bundle as template resolution failed.
1375 * It means we need to try again resolving. */
1376 if (xdst->num_xfrms > 0)
1377 return NULL;
1378 } else if (dst->flags & DST_XFRM_QUEUE) {
1379 return NULL;
1380 } else {
1381 /* Real bundle */
1382 if (stale_bundle(dst))
1383 return NULL;
1384 }
1385
1386 dst_hold(dst);
1387 return flo;
1388 }
1389
1390 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1391 {
1392 struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1393 struct dst_entry *dst = &xdst->u.dst;
1394
1395 if (!xdst->route)
1396 return 0;
1397 if (stale_bundle(dst))
1398 return 0;
1399
1400 return 1;
1401 }
1402
1403 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1404 {
1405 struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1406 struct dst_entry *dst = &xdst->u.dst;
1407
1408 dst_free(dst);
1409 }
1410
1411 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1412 .get = xfrm_bundle_flo_get,
1413 .check = xfrm_bundle_flo_check,
1414 .delete = xfrm_bundle_flo_delete,
1415 };
1416
1417 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1418 {
1419 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1420 struct dst_ops *dst_ops;
1421 struct xfrm_dst *xdst;
1422
1423 if (!afinfo)
1424 return ERR_PTR(-EINVAL);
1425
1426 switch (family) {
1427 case AF_INET:
1428 dst_ops = &net->xfrm.xfrm4_dst_ops;
1429 break;
1430 #if IS_ENABLED(CONFIG_IPV6)
1431 case AF_INET6:
1432 dst_ops = &net->xfrm.xfrm6_dst_ops;
1433 break;
1434 #endif
1435 default:
1436 BUG();
1437 }
1438 xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1439
1440 if (likely(xdst)) {
1441 struct dst_entry *dst = &xdst->u.dst;
1442
1443 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1444 xdst->flo.ops = &xfrm_bundle_fc_ops;
1445 if (afinfo->init_dst)
1446 afinfo->init_dst(net, xdst);
1447 } else
1448 xdst = ERR_PTR(-ENOBUFS);
1449
1450 xfrm_policy_put_afinfo(afinfo);
1451
1452 return xdst;
1453 }
1454
1455 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1456 int nfheader_len)
1457 {
1458 struct xfrm_policy_afinfo *afinfo =
1459 xfrm_policy_get_afinfo(dst->ops->family);
1460 int err;
1461
1462 if (!afinfo)
1463 return -EINVAL;
1464
1465 err = afinfo->init_path(path, dst, nfheader_len);
1466
1467 xfrm_policy_put_afinfo(afinfo);
1468
1469 return err;
1470 }
1471
1472 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1473 const struct flowi *fl)
1474 {
1475 struct xfrm_policy_afinfo *afinfo =
1476 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1477 int err;
1478
1479 if (!afinfo)
1480 return -EINVAL;
1481
1482 err = afinfo->fill_dst(xdst, dev, fl);
1483
1484 xfrm_policy_put_afinfo(afinfo);
1485
1486 return err;
1487 }
1488
1489
1490 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1491 * all the metrics... Shortly, bundle a bundle.
1492 */
1493
1494 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1495 struct xfrm_state **xfrm, int nx,
1496 const struct flowi *fl,
1497 struct dst_entry *dst)
1498 {
1499 struct net *net = xp_net(policy);
1500 unsigned long now = jiffies;
1501 struct net_device *dev;
1502 struct xfrm_mode *inner_mode;
1503 struct dst_entry *dst_prev = NULL;
1504 struct dst_entry *dst0 = NULL;
1505 int i = 0;
1506 int err;
1507 int header_len = 0;
1508 int nfheader_len = 0;
1509 int trailer_len = 0;
1510 int tos;
1511 int family = policy->selector.family;
1512 xfrm_address_t saddr, daddr;
1513
1514 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1515
1516 tos = xfrm_get_tos(fl, family);
1517 err = tos;
1518 if (tos < 0)
1519 goto put_states;
1520
1521 dst_hold(dst);
1522
1523 for (; i < nx; i++) {
1524 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1525 struct dst_entry *dst1 = &xdst->u.dst;
1526
1527 err = PTR_ERR(xdst);
1528 if (IS_ERR(xdst)) {
1529 dst_release(dst);
1530 goto put_states;
1531 }
1532
1533 if (xfrm[i]->sel.family == AF_UNSPEC) {
1534 inner_mode = xfrm_ip2inner_mode(xfrm[i],
1535 xfrm_af2proto(family));
1536 if (!inner_mode) {
1537 err = -EAFNOSUPPORT;
1538 dst_release(dst);
1539 goto put_states;
1540 }
1541 } else
1542 inner_mode = xfrm[i]->inner_mode;
1543
1544 if (!dst_prev)
1545 dst0 = dst1;
1546 else {
1547 dst_prev->child = dst_clone(dst1);
1548 dst1->flags |= DST_NOHASH;
1549 }
1550
1551 xdst->route = dst;
1552 dst_copy_metrics(dst1, dst);
1553
1554 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1555 family = xfrm[i]->props.family;
1556 dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1557 family);
1558 err = PTR_ERR(dst);
1559 if (IS_ERR(dst))
1560 goto put_states;
1561 } else
1562 dst_hold(dst);
1563
1564 dst1->xfrm = xfrm[i];
1565 xdst->xfrm_genid = xfrm[i]->genid;
1566
1567 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1568 dst1->flags |= DST_HOST;
1569 dst1->lastuse = now;
1570
1571 dst1->input = dst_discard;
1572 dst1->output = inner_mode->afinfo->output;
1573
1574 dst1->next = dst_prev;
1575 dst_prev = dst1;
1576
1577 header_len += xfrm[i]->props.header_len;
1578 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1579 nfheader_len += xfrm[i]->props.header_len;
1580 trailer_len += xfrm[i]->props.trailer_len;
1581 }
1582
1583 dst_prev->child = dst;
1584 dst0->path = dst;
1585
1586 err = -ENODEV;
1587 dev = dst->dev;
1588 if (!dev)
1589 goto free_dst;
1590
1591 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1592 xfrm_init_pmtu(dst_prev);
1593
1594 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1595 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1596
1597 err = xfrm_fill_dst(xdst, dev, fl);
1598 if (err)
1599 goto free_dst;
1600
1601 dst_prev->header_len = header_len;
1602 dst_prev->trailer_len = trailer_len;
1603 header_len -= xdst->u.dst.xfrm->props.header_len;
1604 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1605 }
1606
1607 out:
1608 return dst0;
1609
1610 put_states:
1611 for (; i < nx; i++)
1612 xfrm_state_put(xfrm[i]);
1613 free_dst:
1614 if (dst0)
1615 dst_free(dst0);
1616 dst0 = ERR_PTR(err);
1617 goto out;
1618 }
1619
1620 static int inline
1621 xfrm_dst_alloc_copy(void **target, const void *src, int size)
1622 {
1623 if (!*target) {
1624 *target = kmalloc(size, GFP_ATOMIC);
1625 if (!*target)
1626 return -ENOMEM;
1627 }
1628 memcpy(*target, src, size);
1629 return 0;
1630 }
1631
1632 static int inline
1633 xfrm_dst_update_parent(struct dst_entry *dst, const struct xfrm_selector *sel)
1634 {
1635 #ifdef CONFIG_XFRM_SUB_POLICY
1636 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1637 return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1638 sel, sizeof(*sel));
1639 #else
1640 return 0;
1641 #endif
1642 }
1643
1644 static int inline
1645 xfrm_dst_update_origin(struct dst_entry *dst, const struct flowi *fl)
1646 {
1647 #ifdef CONFIG_XFRM_SUB_POLICY
1648 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1649 return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1650 #else
1651 return 0;
1652 #endif
1653 }
1654
1655 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1656 struct xfrm_policy **pols,
1657 int *num_pols, int *num_xfrms)
1658 {
1659 int i;
1660
1661 if (*num_pols == 0 || !pols[0]) {
1662 *num_pols = 0;
1663 *num_xfrms = 0;
1664 return 0;
1665 }
1666 if (IS_ERR(pols[0]))
1667 return PTR_ERR(pols[0]);
1668
1669 *num_xfrms = pols[0]->xfrm_nr;
1670
1671 #ifdef CONFIG_XFRM_SUB_POLICY
1672 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1673 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1674 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1675 XFRM_POLICY_TYPE_MAIN,
1676 fl, family,
1677 XFRM_POLICY_OUT);
1678 if (pols[1]) {
1679 if (IS_ERR(pols[1])) {
1680 xfrm_pols_put(pols, *num_pols);
1681 return PTR_ERR(pols[1]);
1682 }
1683 (*num_pols) ++;
1684 (*num_xfrms) += pols[1]->xfrm_nr;
1685 }
1686 }
1687 #endif
1688 for (i = 0; i < *num_pols; i++) {
1689 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1690 *num_xfrms = -1;
1691 break;
1692 }
1693 }
1694
1695 return 0;
1696
1697 }
1698
1699 static struct xfrm_dst *
1700 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1701 const struct flowi *fl, u16 family,
1702 struct dst_entry *dst_orig)
1703 {
1704 struct net *net = xp_net(pols[0]);
1705 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1706 struct dst_entry *dst;
1707 struct xfrm_dst *xdst;
1708 int err;
1709
1710 /* Try to instantiate a bundle */
1711 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1712 if (err <= 0) {
1713 if (err != 0 && err != -EAGAIN)
1714 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1715 return ERR_PTR(err);
1716 }
1717
1718 dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1719 if (IS_ERR(dst)) {
1720 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1721 return ERR_CAST(dst);
1722 }
1723
1724 xdst = (struct xfrm_dst *)dst;
1725 xdst->num_xfrms = err;
1726 if (num_pols > 1)
1727 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1728 else
1729 err = xfrm_dst_update_origin(dst, fl);
1730 if (unlikely(err)) {
1731 dst_free(dst);
1732 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1733 return ERR_PTR(err);
1734 }
1735
1736 xdst->num_pols = num_pols;
1737 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1738 xdst->policy_genid = atomic_read(&pols[0]->genid);
1739
1740 return xdst;
1741 }
1742
1743 static void xfrm_policy_queue_process(unsigned long arg)
1744 {
1745 int err = 0;
1746 struct sk_buff *skb;
1747 struct sock *sk;
1748 struct dst_entry *dst;
1749 struct net_device *dev;
1750 struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1751 struct xfrm_policy_queue *pq = &pol->polq;
1752 struct flowi fl;
1753 struct sk_buff_head list;
1754
1755 spin_lock(&pq->hold_queue.lock);
1756 skb = skb_peek(&pq->hold_queue);
1757 dst = skb_dst(skb);
1758 sk = skb->sk;
1759 xfrm_decode_session(skb, &fl, dst->ops->family);
1760 spin_unlock(&pq->hold_queue.lock);
1761
1762 dst_hold(dst->path);
1763 dst = xfrm_lookup(xp_net(pol), dst->path, &fl,
1764 sk, 0);
1765 if (IS_ERR(dst))
1766 goto purge_queue;
1767
1768 if (dst->flags & DST_XFRM_QUEUE) {
1769 dst_release(dst);
1770
1771 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1772 goto purge_queue;
1773
1774 pq->timeout = pq->timeout << 1;
1775 mod_timer(&pq->hold_timer, jiffies + pq->timeout);
1776 return;
1777 }
1778
1779 dst_release(dst);
1780
1781 __skb_queue_head_init(&list);
1782
1783 spin_lock(&pq->hold_queue.lock);
1784 pq->timeout = 0;
1785 skb_queue_splice_init(&pq->hold_queue, &list);
1786 spin_unlock(&pq->hold_queue.lock);
1787
1788 while (!skb_queue_empty(&list)) {
1789 skb = __skb_dequeue(&list);
1790
1791 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1792 dst_hold(skb_dst(skb)->path);
1793 dst = xfrm_lookup(xp_net(pol), skb_dst(skb)->path,
1794 &fl, skb->sk, 0);
1795 if (IS_ERR(dst)) {
1796 dev_put(skb->dev);
1797 kfree_skb(skb);
1798 continue;
1799 }
1800
1801 nf_reset(skb);
1802 skb_dst_drop(skb);
1803 skb_dst_set(skb, dst);
1804
1805 dev = skb->dev;
1806 err = dst_output(skb);
1807 dev_put(dev);
1808 }
1809
1810 return;
1811
1812 purge_queue:
1813 pq->timeout = 0;
1814 xfrm_queue_purge(&pq->hold_queue);
1815 }
1816
1817 static int xdst_queue_output(struct sk_buff *skb)
1818 {
1819 unsigned long sched_next;
1820 struct dst_entry *dst = skb_dst(skb);
1821 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1822 struct xfrm_policy_queue *pq = &xdst->pols[0]->polq;
1823
1824 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1825 kfree_skb(skb);
1826 return -EAGAIN;
1827 }
1828
1829 skb_dst_force(skb);
1830 dev_hold(skb->dev);
1831
1832 spin_lock_bh(&pq->hold_queue.lock);
1833
1834 if (!pq->timeout)
1835 pq->timeout = XFRM_QUEUE_TMO_MIN;
1836
1837 sched_next = jiffies + pq->timeout;
1838
1839 if (del_timer(&pq->hold_timer)) {
1840 if (time_before(pq->hold_timer.expires, sched_next))
1841 sched_next = pq->hold_timer.expires;
1842 }
1843
1844 __skb_queue_tail(&pq->hold_queue, skb);
1845 mod_timer(&pq->hold_timer, sched_next);
1846
1847 spin_unlock_bh(&pq->hold_queue.lock);
1848
1849 return 0;
1850 }
1851
1852 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1853 struct dst_entry *dst,
1854 const struct flowi *fl,
1855 int num_xfrms,
1856 u16 family)
1857 {
1858 int err;
1859 struct net_device *dev;
1860 struct dst_entry *dst1;
1861 struct xfrm_dst *xdst;
1862
1863 xdst = xfrm_alloc_dst(net, family);
1864 if (IS_ERR(xdst))
1865 return xdst;
1866
1867 if (net->xfrm.sysctl_larval_drop || num_xfrms <= 0 ||
1868 (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP))
1869 return xdst;
1870
1871 dst1 = &xdst->u.dst;
1872 dst_hold(dst);
1873 xdst->route = dst;
1874
1875 dst_copy_metrics(dst1, dst);
1876
1877 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1878 dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
1879 dst1->lastuse = jiffies;
1880
1881 dst1->input = dst_discard;
1882 dst1->output = xdst_queue_output;
1883
1884 dst_hold(dst);
1885 dst1->child = dst;
1886 dst1->path = dst;
1887
1888 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
1889
1890 err = -ENODEV;
1891 dev = dst->dev;
1892 if (!dev)
1893 goto free_dst;
1894
1895 err = xfrm_fill_dst(xdst, dev, fl);
1896 if (err)
1897 goto free_dst;
1898
1899 out:
1900 return xdst;
1901
1902 free_dst:
1903 dst_release(dst1);
1904 xdst = ERR_PTR(err);
1905 goto out;
1906 }
1907
1908 static struct flow_cache_object *
1909 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
1910 struct flow_cache_object *oldflo, void *ctx)
1911 {
1912 struct dst_entry *dst_orig = (struct dst_entry *)ctx;
1913 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1914 struct xfrm_dst *xdst, *new_xdst;
1915 int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
1916
1917 /* Check if the policies from old bundle are usable */
1918 xdst = NULL;
1919 if (oldflo) {
1920 xdst = container_of(oldflo, struct xfrm_dst, flo);
1921 num_pols = xdst->num_pols;
1922 num_xfrms = xdst->num_xfrms;
1923 pol_dead = 0;
1924 for (i = 0; i < num_pols; i++) {
1925 pols[i] = xdst->pols[i];
1926 pol_dead |= pols[i]->walk.dead;
1927 }
1928 if (pol_dead) {
1929 dst_free(&xdst->u.dst);
1930 xdst = NULL;
1931 num_pols = 0;
1932 num_xfrms = 0;
1933 oldflo = NULL;
1934 }
1935 }
1936
1937 /* Resolve policies to use if we couldn't get them from
1938 * previous cache entry */
1939 if (xdst == NULL) {
1940 num_pols = 1;
1941 pols[0] = __xfrm_policy_lookup(net, fl, family, dir);
1942 err = xfrm_expand_policies(fl, family, pols,
1943 &num_pols, &num_xfrms);
1944 if (err < 0)
1945 goto inc_error;
1946 if (num_pols == 0)
1947 return NULL;
1948 if (num_xfrms <= 0)
1949 goto make_dummy_bundle;
1950 }
1951
1952 new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, dst_orig);
1953 if (IS_ERR(new_xdst)) {
1954 err = PTR_ERR(new_xdst);
1955 if (err != -EAGAIN)
1956 goto error;
1957 if (oldflo == NULL)
1958 goto make_dummy_bundle;
1959 dst_hold(&xdst->u.dst);
1960 return oldflo;
1961 } else if (new_xdst == NULL) {
1962 num_xfrms = 0;
1963 if (oldflo == NULL)
1964 goto make_dummy_bundle;
1965 xdst->num_xfrms = 0;
1966 dst_hold(&xdst->u.dst);
1967 return oldflo;
1968 }
1969
1970 /* Kill the previous bundle */
1971 if (xdst) {
1972 /* The policies were stolen for newly generated bundle */
1973 xdst->num_pols = 0;
1974 dst_free(&xdst->u.dst);
1975 }
1976
1977 /* Flow cache does not have reference, it dst_free()'s,
1978 * but we do need to return one reference for original caller */
1979 dst_hold(&new_xdst->u.dst);
1980 return &new_xdst->flo;
1981
1982 make_dummy_bundle:
1983 /* We found policies, but there's no bundles to instantiate:
1984 * either because the policy blocks, has no transformations or
1985 * we could not build template (no xfrm_states).*/
1986 xdst = xfrm_create_dummy_bundle(net, dst_orig, fl, num_xfrms, family);
1987 if (IS_ERR(xdst)) {
1988 xfrm_pols_put(pols, num_pols);
1989 return ERR_CAST(xdst);
1990 }
1991 xdst->num_pols = num_pols;
1992 xdst->num_xfrms = num_xfrms;
1993 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1994
1995 dst_hold(&xdst->u.dst);
1996 return &xdst->flo;
1997
1998 inc_error:
1999 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2000 error:
2001 if (xdst != NULL)
2002 dst_free(&xdst->u.dst);
2003 else
2004 xfrm_pols_put(pols, num_pols);
2005 return ERR_PTR(err);
2006 }
2007
2008 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2009 struct dst_entry *dst_orig)
2010 {
2011 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2012 struct dst_entry *ret;
2013
2014 if (!afinfo) {
2015 dst_release(dst_orig);
2016 return ERR_PTR(-EINVAL);
2017 } else {
2018 ret = afinfo->blackhole_route(net, dst_orig);
2019 }
2020 xfrm_policy_put_afinfo(afinfo);
2021
2022 return ret;
2023 }
2024
2025 /* Main function: finds/creates a bundle for given flow.
2026 *
2027 * At the moment we eat a raw IP route. Mostly to speed up lookups
2028 * on interfaces with disabled IPsec.
2029 */
2030 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2031 const struct flowi *fl,
2032 struct sock *sk, int flags)
2033 {
2034 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2035 struct flow_cache_object *flo;
2036 struct xfrm_dst *xdst;
2037 struct dst_entry *dst, *route;
2038 u16 family = dst_orig->ops->family;
2039 u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2040 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2041
2042 restart:
2043 dst = NULL;
2044 xdst = NULL;
2045 route = NULL;
2046
2047 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2048 num_pols = 1;
2049 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2050 err = xfrm_expand_policies(fl, family, pols,
2051 &num_pols, &num_xfrms);
2052 if (err < 0)
2053 goto dropdst;
2054
2055 if (num_pols) {
2056 if (num_xfrms <= 0) {
2057 drop_pols = num_pols;
2058 goto no_transform;
2059 }
2060
2061 xdst = xfrm_resolve_and_create_bundle(
2062 pols, num_pols, fl,
2063 family, dst_orig);
2064 if (IS_ERR(xdst)) {
2065 xfrm_pols_put(pols, num_pols);
2066 err = PTR_ERR(xdst);
2067 goto dropdst;
2068 } else if (xdst == NULL) {
2069 num_xfrms = 0;
2070 drop_pols = num_pols;
2071 goto no_transform;
2072 }
2073
2074 dst_hold(&xdst->u.dst);
2075
2076 spin_lock_bh(&xfrm_policy_sk_bundle_lock);
2077 xdst->u.dst.next = xfrm_policy_sk_bundles;
2078 xfrm_policy_sk_bundles = &xdst->u.dst;
2079 spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
2080
2081 route = xdst->route;
2082 }
2083 }
2084
2085 if (xdst == NULL) {
2086 /* To accelerate a bit... */
2087 if ((dst_orig->flags & DST_NOXFRM) ||
2088 !net->xfrm.policy_count[XFRM_POLICY_OUT])
2089 goto nopol;
2090
2091 flo = flow_cache_lookup(net, fl, family, dir,
2092 xfrm_bundle_lookup, dst_orig);
2093 if (flo == NULL)
2094 goto nopol;
2095 if (IS_ERR(flo)) {
2096 err = PTR_ERR(flo);
2097 goto dropdst;
2098 }
2099 xdst = container_of(flo, struct xfrm_dst, flo);
2100
2101 num_pols = xdst->num_pols;
2102 num_xfrms = xdst->num_xfrms;
2103 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy*) * num_pols);
2104 route = xdst->route;
2105 }
2106
2107 dst = &xdst->u.dst;
2108 if (route == NULL && num_xfrms > 0) {
2109 /* The only case when xfrm_bundle_lookup() returns a
2110 * bundle with null route, is when the template could
2111 * not be resolved. It means policies are there, but
2112 * bundle could not be created, since we don't yet
2113 * have the xfrm_state's. We need to wait for KM to
2114 * negotiate new SA's or bail out with error.*/
2115 if (net->xfrm.sysctl_larval_drop) {
2116 /* EREMOTE tells the caller to generate
2117 * a one-shot blackhole route. */
2118 dst_release(dst);
2119 xfrm_pols_put(pols, drop_pols);
2120 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2121
2122 return make_blackhole(net, family, dst_orig);
2123 }
2124 if (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP) {
2125 DECLARE_WAITQUEUE(wait, current);
2126
2127 add_wait_queue(&net->xfrm.km_waitq, &wait);
2128 set_current_state(TASK_INTERRUPTIBLE);
2129 schedule();
2130 set_current_state(TASK_RUNNING);
2131 remove_wait_queue(&net->xfrm.km_waitq, &wait);
2132
2133 if (!signal_pending(current)) {
2134 dst_release(dst);
2135 goto restart;
2136 }
2137
2138 err = -ERESTART;
2139 } else
2140 err = -EAGAIN;
2141
2142 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2143 goto error;
2144 }
2145
2146 no_transform:
2147 if (num_pols == 0)
2148 goto nopol;
2149
2150 if ((flags & XFRM_LOOKUP_ICMP) &&
2151 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2152 err = -ENOENT;
2153 goto error;
2154 }
2155
2156 for (i = 0; i < num_pols; i++)
2157 pols[i]->curlft.use_time = get_seconds();
2158
2159 if (num_xfrms < 0) {
2160 /* Prohibit the flow */
2161 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2162 err = -EPERM;
2163 goto error;
2164 } else if (num_xfrms > 0) {
2165 /* Flow transformed */
2166 dst_release(dst_orig);
2167 } else {
2168 /* Flow passes untransformed */
2169 dst_release(dst);
2170 dst = dst_orig;
2171 }
2172 ok:
2173 xfrm_pols_put(pols, drop_pols);
2174 if (dst && dst->xfrm &&
2175 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2176 dst->flags |= DST_XFRM_TUNNEL;
2177 return dst;
2178
2179 nopol:
2180 if (!(flags & XFRM_LOOKUP_ICMP)) {
2181 dst = dst_orig;
2182 goto ok;
2183 }
2184 err = -ENOENT;
2185 error:
2186 dst_release(dst);
2187 dropdst:
2188 dst_release(dst_orig);
2189 xfrm_pols_put(pols, drop_pols);
2190 return ERR_PTR(err);
2191 }
2192 EXPORT_SYMBOL(xfrm_lookup);
2193
2194 static inline int
2195 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2196 {
2197 struct xfrm_state *x;
2198
2199 if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2200 return 0;
2201 x = skb->sp->xvec[idx];
2202 if (!x->type->reject)
2203 return 0;
2204 return x->type->reject(x, skb, fl);
2205 }
2206
2207 /* When skb is transformed back to its "native" form, we have to
2208 * check policy restrictions. At the moment we make this in maximally
2209 * stupid way. Shame on me. :-) Of course, connected sockets must
2210 * have policy cached at them.
2211 */
2212
2213 static inline int
2214 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2215 unsigned short family)
2216 {
2217 if (xfrm_state_kern(x))
2218 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2219 return x->id.proto == tmpl->id.proto &&
2220 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2221 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2222 x->props.mode == tmpl->mode &&
2223 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2224 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2225 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2226 xfrm_state_addr_cmp(tmpl, x, family));
2227 }
2228
2229 /*
2230 * 0 or more than 0 is returned when validation is succeeded (either bypass
2231 * because of optional transport mode, or next index of the mathced secpath
2232 * state with the template.
2233 * -1 is returned when no matching template is found.
2234 * Otherwise "-2 - errored_index" is returned.
2235 */
2236 static inline int
2237 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2238 unsigned short family)
2239 {
2240 int idx = start;
2241
2242 if (tmpl->optional) {
2243 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2244 return start;
2245 } else
2246 start = -1;
2247 for (; idx < sp->len; idx++) {
2248 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2249 return ++idx;
2250 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2251 if (start == -1)
2252 start = -2-idx;
2253 break;
2254 }
2255 }
2256 return start;
2257 }
2258
2259 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2260 unsigned int family, int reverse)
2261 {
2262 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2263 int err;
2264
2265 if (unlikely(afinfo == NULL))
2266 return -EAFNOSUPPORT;
2267
2268 afinfo->decode_session(skb, fl, reverse);
2269 err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2270 xfrm_policy_put_afinfo(afinfo);
2271 return err;
2272 }
2273 EXPORT_SYMBOL(__xfrm_decode_session);
2274
2275 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2276 {
2277 for (; k < sp->len; k++) {
2278 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2279 *idxp = k;
2280 return 1;
2281 }
2282 }
2283
2284 return 0;
2285 }
2286
2287 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2288 unsigned short family)
2289 {
2290 struct net *net = dev_net(skb->dev);
2291 struct xfrm_policy *pol;
2292 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2293 int npols = 0;
2294 int xfrm_nr;
2295 int pi;
2296 int reverse;
2297 struct flowi fl;
2298 u8 fl_dir;
2299 int xerr_idx = -1;
2300
2301 reverse = dir & ~XFRM_POLICY_MASK;
2302 dir &= XFRM_POLICY_MASK;
2303 fl_dir = policy_to_flow_dir(dir);
2304
2305 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2306 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2307 return 0;
2308 }
2309
2310 nf_nat_decode_session(skb, &fl, family);
2311
2312 /* First, check used SA against their selectors. */
2313 if (skb->sp) {
2314 int i;
2315
2316 for (i=skb->sp->len-1; i>=0; i--) {
2317 struct xfrm_state *x = skb->sp->xvec[i];
2318 if (!xfrm_selector_match(&x->sel, &fl, family)) {
2319 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2320 return 0;
2321 }
2322 }
2323 }
2324
2325 pol = NULL;
2326 if (sk && sk->sk_policy[dir]) {
2327 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2328 if (IS_ERR(pol)) {
2329 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2330 return 0;
2331 }
2332 }
2333
2334 if (!pol) {
2335 struct flow_cache_object *flo;
2336
2337 flo = flow_cache_lookup(net, &fl, family, fl_dir,
2338 xfrm_policy_lookup, NULL);
2339 if (IS_ERR_OR_NULL(flo))
2340 pol = ERR_CAST(flo);
2341 else
2342 pol = container_of(flo, struct xfrm_policy, flo);
2343 }
2344
2345 if (IS_ERR(pol)) {
2346 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2347 return 0;
2348 }
2349
2350 if (!pol) {
2351 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2352 xfrm_secpath_reject(xerr_idx, skb, &fl);
2353 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2354 return 0;
2355 }
2356 return 1;
2357 }
2358
2359 pol->curlft.use_time = get_seconds();
2360
2361 pols[0] = pol;
2362 npols ++;
2363 #ifdef CONFIG_XFRM_SUB_POLICY
2364 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2365 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2366 &fl, family,
2367 XFRM_POLICY_IN);
2368 if (pols[1]) {
2369 if (IS_ERR(pols[1])) {
2370 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2371 return 0;
2372 }
2373 pols[1]->curlft.use_time = get_seconds();
2374 npols ++;
2375 }
2376 }
2377 #endif
2378
2379 if (pol->action == XFRM_POLICY_ALLOW) {
2380 struct sec_path *sp;
2381 static struct sec_path dummy;
2382 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2383 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2384 struct xfrm_tmpl **tpp = tp;
2385 int ti = 0;
2386 int i, k;
2387
2388 if ((sp = skb->sp) == NULL)
2389 sp = &dummy;
2390
2391 for (pi = 0; pi < npols; pi++) {
2392 if (pols[pi] != pol &&
2393 pols[pi]->action != XFRM_POLICY_ALLOW) {
2394 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2395 goto reject;
2396 }
2397 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2398 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2399 goto reject_error;
2400 }
2401 for (i = 0; i < pols[pi]->xfrm_nr; i++)
2402 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2403 }
2404 xfrm_nr = ti;
2405 if (npols > 1) {
2406 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
2407 tpp = stp;
2408 }
2409
2410 /* For each tunnel xfrm, find the first matching tmpl.
2411 * For each tmpl before that, find corresponding xfrm.
2412 * Order is _important_. Later we will implement
2413 * some barriers, but at the moment barriers
2414 * are implied between each two transformations.
2415 */
2416 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2417 k = xfrm_policy_ok(tpp[i], sp, k, family);
2418 if (k < 0) {
2419 if (k < -1)
2420 /* "-2 - errored_index" returned */
2421 xerr_idx = -(2+k);
2422 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2423 goto reject;
2424 }
2425 }
2426
2427 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2428 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2429 goto reject;
2430 }
2431
2432 xfrm_pols_put(pols, npols);
2433 return 1;
2434 }
2435 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2436
2437 reject:
2438 xfrm_secpath_reject(xerr_idx, skb, &fl);
2439 reject_error:
2440 xfrm_pols_put(pols, npols);
2441 return 0;
2442 }
2443 EXPORT_SYMBOL(__xfrm_policy_check);
2444
2445 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2446 {
2447 struct net *net = dev_net(skb->dev);
2448 struct flowi fl;
2449 struct dst_entry *dst;
2450 int res = 1;
2451
2452 if (xfrm_decode_session(skb, &fl, family) < 0) {
2453 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2454 return 0;
2455 }
2456
2457 skb_dst_force(skb);
2458
2459 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, 0);
2460 if (IS_ERR(dst)) {
2461 res = 0;
2462 dst = NULL;
2463 }
2464 skb_dst_set(skb, dst);
2465 return res;
2466 }
2467 EXPORT_SYMBOL(__xfrm_route_forward);
2468
2469 /* Optimize later using cookies and generation ids. */
2470
2471 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2472 {
2473 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2474 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2475 * get validated by dst_ops->check on every use. We do this
2476 * because when a normal route referenced by an XFRM dst is
2477 * obsoleted we do not go looking around for all parent
2478 * referencing XFRM dsts so that we can invalidate them. It
2479 * is just too much work. Instead we make the checks here on
2480 * every use. For example:
2481 *
2482 * XFRM dst A --> IPv4 dst X
2483 *
2484 * X is the "xdst->route" of A (X is also the "dst->path" of A
2485 * in this example). If X is marked obsolete, "A" will not
2486 * notice. That's what we are validating here via the
2487 * stale_bundle() check.
2488 *
2489 * When a policy's bundle is pruned, we dst_free() the XFRM
2490 * dst which causes it's ->obsolete field to be set to
2491 * DST_OBSOLETE_DEAD. If an XFRM dst has been pruned like
2492 * this, we want to force a new route lookup.
2493 */
2494 if (dst->obsolete < 0 && !stale_bundle(dst))
2495 return dst;
2496
2497 return NULL;
2498 }
2499
2500 static int stale_bundle(struct dst_entry *dst)
2501 {
2502 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2503 }
2504
2505 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2506 {
2507 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2508 dst->dev = dev_net(dev)->loopback_dev;
2509 dev_hold(dst->dev);
2510 dev_put(dev);
2511 }
2512 }
2513 EXPORT_SYMBOL(xfrm_dst_ifdown);
2514
2515 static void xfrm_link_failure(struct sk_buff *skb)
2516 {
2517 /* Impossible. Such dst must be popped before reaches point of failure. */
2518 }
2519
2520 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2521 {
2522 if (dst) {
2523 if (dst->obsolete) {
2524 dst_release(dst);
2525 dst = NULL;
2526 }
2527 }
2528 return dst;
2529 }
2530
2531 static void __xfrm_garbage_collect(struct net *net)
2532 {
2533 struct dst_entry *head, *next;
2534
2535 spin_lock_bh(&xfrm_policy_sk_bundle_lock);
2536 head = xfrm_policy_sk_bundles;
2537 xfrm_policy_sk_bundles = NULL;
2538 spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
2539
2540 while (head) {
2541 next = head->next;
2542 dst_free(head);
2543 head = next;
2544 }
2545 }
2546
2547 static void xfrm_garbage_collect(struct net *net)
2548 {
2549 flow_cache_flush();
2550 __xfrm_garbage_collect(net);
2551 }
2552
2553 static void xfrm_garbage_collect_deferred(struct net *net)
2554 {
2555 flow_cache_flush_deferred();
2556 __xfrm_garbage_collect(net);
2557 }
2558
2559 static void xfrm_init_pmtu(struct dst_entry *dst)
2560 {
2561 do {
2562 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2563 u32 pmtu, route_mtu_cached;
2564
2565 pmtu = dst_mtu(dst->child);
2566 xdst->child_mtu_cached = pmtu;
2567
2568 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2569
2570 route_mtu_cached = dst_mtu(xdst->route);
2571 xdst->route_mtu_cached = route_mtu_cached;
2572
2573 if (pmtu > route_mtu_cached)
2574 pmtu = route_mtu_cached;
2575
2576 dst_metric_set(dst, RTAX_MTU, pmtu);
2577 } while ((dst = dst->next));
2578 }
2579
2580 /* Check that the bundle accepts the flow and its components are
2581 * still valid.
2582 */
2583
2584 static int xfrm_bundle_ok(struct xfrm_dst *first)
2585 {
2586 struct dst_entry *dst = &first->u.dst;
2587 struct xfrm_dst *last;
2588 u32 mtu;
2589
2590 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2591 (dst->dev && !netif_running(dst->dev)))
2592 return 0;
2593
2594 if (dst->flags & DST_XFRM_QUEUE)
2595 return 1;
2596
2597 last = NULL;
2598
2599 do {
2600 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2601
2602 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2603 return 0;
2604 if (xdst->xfrm_genid != dst->xfrm->genid)
2605 return 0;
2606 if (xdst->num_pols > 0 &&
2607 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2608 return 0;
2609
2610 mtu = dst_mtu(dst->child);
2611 if (xdst->child_mtu_cached != mtu) {
2612 last = xdst;
2613 xdst->child_mtu_cached = mtu;
2614 }
2615
2616 if (!dst_check(xdst->route, xdst->route_cookie))
2617 return 0;
2618 mtu = dst_mtu(xdst->route);
2619 if (xdst->route_mtu_cached != mtu) {
2620 last = xdst;
2621 xdst->route_mtu_cached = mtu;
2622 }
2623
2624 dst = dst->child;
2625 } while (dst->xfrm);
2626
2627 if (likely(!last))
2628 return 1;
2629
2630 mtu = last->child_mtu_cached;
2631 for (;;) {
2632 dst = &last->u.dst;
2633
2634 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2635 if (mtu > last->route_mtu_cached)
2636 mtu = last->route_mtu_cached;
2637 dst_metric_set(dst, RTAX_MTU, mtu);
2638
2639 if (last == first)
2640 break;
2641
2642 last = (struct xfrm_dst *)last->u.dst.next;
2643 last->child_mtu_cached = mtu;
2644 }
2645
2646 return 1;
2647 }
2648
2649 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2650 {
2651 return dst_metric_advmss(dst->path);
2652 }
2653
2654 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2655 {
2656 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2657
2658 return mtu ? : dst_mtu(dst->path);
2659 }
2660
2661 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2662 struct sk_buff *skb,
2663 const void *daddr)
2664 {
2665 return dst->path->ops->neigh_lookup(dst, skb, daddr);
2666 }
2667
2668 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2669 {
2670 struct net *net;
2671 int err = 0;
2672 if (unlikely(afinfo == NULL))
2673 return -EINVAL;
2674 if (unlikely(afinfo->family >= NPROTO))
2675 return -EAFNOSUPPORT;
2676 spin_lock(&xfrm_policy_afinfo_lock);
2677 if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2678 err = -ENOBUFS;
2679 else {
2680 struct dst_ops *dst_ops = afinfo->dst_ops;
2681 if (likely(dst_ops->kmem_cachep == NULL))
2682 dst_ops->kmem_cachep = xfrm_dst_cache;
2683 if (likely(dst_ops->check == NULL))
2684 dst_ops->check = xfrm_dst_check;
2685 if (likely(dst_ops->default_advmss == NULL))
2686 dst_ops->default_advmss = xfrm_default_advmss;
2687 if (likely(dst_ops->mtu == NULL))
2688 dst_ops->mtu = xfrm_mtu;
2689 if (likely(dst_ops->negative_advice == NULL))
2690 dst_ops->negative_advice = xfrm_negative_advice;
2691 if (likely(dst_ops->link_failure == NULL))
2692 dst_ops->link_failure = xfrm_link_failure;
2693 if (likely(dst_ops->neigh_lookup == NULL))
2694 dst_ops->neigh_lookup = xfrm_neigh_lookup;
2695 if (likely(afinfo->garbage_collect == NULL))
2696 afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2697 rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
2698 }
2699 spin_unlock(&xfrm_policy_afinfo_lock);
2700
2701 rtnl_lock();
2702 for_each_net(net) {
2703 struct dst_ops *xfrm_dst_ops;
2704
2705 switch (afinfo->family) {
2706 case AF_INET:
2707 xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2708 break;
2709 #if IS_ENABLED(CONFIG_IPV6)
2710 case AF_INET6:
2711 xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2712 break;
2713 #endif
2714 default:
2715 BUG();
2716 }
2717 *xfrm_dst_ops = *afinfo->dst_ops;
2718 }
2719 rtnl_unlock();
2720
2721 return err;
2722 }
2723 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2724
2725 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2726 {
2727 int err = 0;
2728 if (unlikely(afinfo == NULL))
2729 return -EINVAL;
2730 if (unlikely(afinfo->family >= NPROTO))
2731 return -EAFNOSUPPORT;
2732 spin_lock(&xfrm_policy_afinfo_lock);
2733 if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2734 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2735 err = -EINVAL;
2736 else
2737 RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
2738 NULL);
2739 }
2740 spin_unlock(&xfrm_policy_afinfo_lock);
2741 if (!err) {
2742 struct dst_ops *dst_ops = afinfo->dst_ops;
2743
2744 synchronize_rcu();
2745
2746 dst_ops->kmem_cachep = NULL;
2747 dst_ops->check = NULL;
2748 dst_ops->negative_advice = NULL;
2749 dst_ops->link_failure = NULL;
2750 afinfo->garbage_collect = NULL;
2751 }
2752 return err;
2753 }
2754 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2755
2756 static void __net_init xfrm_dst_ops_init(struct net *net)
2757 {
2758 struct xfrm_policy_afinfo *afinfo;
2759
2760 rcu_read_lock();
2761 afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]);
2762 if (afinfo)
2763 net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2764 #if IS_ENABLED(CONFIG_IPV6)
2765 afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]);
2766 if (afinfo)
2767 net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2768 #endif
2769 rcu_read_unlock();
2770 }
2771
2772 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2773 {
2774 struct net_device *dev = ptr;
2775
2776 switch (event) {
2777 case NETDEV_DOWN:
2778 xfrm_garbage_collect(dev_net(dev));
2779 }
2780 return NOTIFY_DONE;
2781 }
2782
2783 static struct notifier_block xfrm_dev_notifier = {
2784 .notifier_call = xfrm_dev_event,
2785 };
2786
2787 #ifdef CONFIG_XFRM_STATISTICS
2788 static int __net_init xfrm_statistics_init(struct net *net)
2789 {
2790 int rv;
2791
2792 if (snmp_mib_init((void __percpu **)net->mib.xfrm_statistics,
2793 sizeof(struct linux_xfrm_mib),
2794 __alignof__(struct linux_xfrm_mib)) < 0)
2795 return -ENOMEM;
2796 rv = xfrm_proc_init(net);
2797 if (rv < 0)
2798 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2799 return rv;
2800 }
2801
2802 static void xfrm_statistics_fini(struct net *net)
2803 {
2804 xfrm_proc_fini(net);
2805 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2806 }
2807 #else
2808 static int __net_init xfrm_statistics_init(struct net *net)
2809 {
2810 return 0;
2811 }
2812
2813 static void xfrm_statistics_fini(struct net *net)
2814 {
2815 }
2816 #endif
2817
2818 static int __net_init xfrm_policy_init(struct net *net)
2819 {
2820 unsigned int hmask, sz;
2821 int dir;
2822
2823 if (net_eq(net, &init_net))
2824 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2825 sizeof(struct xfrm_dst),
2826 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2827 NULL);
2828
2829 hmask = 8 - 1;
2830 sz = (hmask+1) * sizeof(struct hlist_head);
2831
2832 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2833 if (!net->xfrm.policy_byidx)
2834 goto out_byidx;
2835 net->xfrm.policy_idx_hmask = hmask;
2836
2837 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2838 struct xfrm_policy_hash *htab;
2839
2840 net->xfrm.policy_count[dir] = 0;
2841 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2842
2843 htab = &net->xfrm.policy_bydst[dir];
2844 htab->table = xfrm_hash_alloc(sz);
2845 if (!htab->table)
2846 goto out_bydst;
2847 htab->hmask = hmask;
2848 }
2849
2850 INIT_LIST_HEAD(&net->xfrm.policy_all);
2851 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2852 if (net_eq(net, &init_net))
2853 register_netdevice_notifier(&xfrm_dev_notifier);
2854 return 0;
2855
2856 out_bydst:
2857 for (dir--; dir >= 0; dir--) {
2858 struct xfrm_policy_hash *htab;
2859
2860 htab = &net->xfrm.policy_bydst[dir];
2861 xfrm_hash_free(htab->table, sz);
2862 }
2863 xfrm_hash_free(net->xfrm.policy_byidx, sz);
2864 out_byidx:
2865 return -ENOMEM;
2866 }
2867
2868 static void xfrm_policy_fini(struct net *net)
2869 {
2870 struct xfrm_audit audit_info;
2871 unsigned int sz;
2872 int dir;
2873
2874 flush_work(&net->xfrm.policy_hash_work);
2875 #ifdef CONFIG_XFRM_SUB_POLICY
2876 audit_info.loginuid = INVALID_UID;
2877 audit_info.sessionid = -1;
2878 audit_info.secid = 0;
2879 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info);
2880 #endif
2881 audit_info.loginuid = INVALID_UID;
2882 audit_info.sessionid = -1;
2883 audit_info.secid = 0;
2884 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info);
2885
2886 WARN_ON(!list_empty(&net->xfrm.policy_all));
2887
2888 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2889 struct xfrm_policy_hash *htab;
2890
2891 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2892
2893 htab = &net->xfrm.policy_bydst[dir];
2894 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2895 WARN_ON(!hlist_empty(htab->table));
2896 xfrm_hash_free(htab->table, sz);
2897 }
2898
2899 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2900 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2901 xfrm_hash_free(net->xfrm.policy_byidx, sz);
2902 }
2903
2904 static int __net_init xfrm_net_init(struct net *net)
2905 {
2906 int rv;
2907
2908 rv = xfrm_statistics_init(net);
2909 if (rv < 0)
2910 goto out_statistics;
2911 rv = xfrm_state_init(net);
2912 if (rv < 0)
2913 goto out_state;
2914 rv = xfrm_policy_init(net);
2915 if (rv < 0)
2916 goto out_policy;
2917 xfrm_dst_ops_init(net);
2918 rv = xfrm_sysctl_init(net);
2919 if (rv < 0)
2920 goto out_sysctl;
2921 return 0;
2922
2923 out_sysctl:
2924 xfrm_policy_fini(net);
2925 out_policy:
2926 xfrm_state_fini(net);
2927 out_state:
2928 xfrm_statistics_fini(net);
2929 out_statistics:
2930 return rv;
2931 }
2932
2933 static void __net_exit xfrm_net_exit(struct net *net)
2934 {
2935 xfrm_sysctl_fini(net);
2936 xfrm_policy_fini(net);
2937 xfrm_state_fini(net);
2938 xfrm_statistics_fini(net);
2939 }
2940
2941 static struct pernet_operations __net_initdata xfrm_net_ops = {
2942 .init = xfrm_net_init,
2943 .exit = xfrm_net_exit,
2944 };
2945
2946 void __init xfrm_init(void)
2947 {
2948 register_pernet_subsys(&xfrm_net_ops);
2949 xfrm_input_init();
2950 }
2951
2952 #ifdef CONFIG_AUDITSYSCALL
2953 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2954 struct audit_buffer *audit_buf)
2955 {
2956 struct xfrm_sec_ctx *ctx = xp->security;
2957 struct xfrm_selector *sel = &xp->selector;
2958
2959 if (ctx)
2960 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2961 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2962
2963 switch(sel->family) {
2964 case AF_INET:
2965 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2966 if (sel->prefixlen_s != 32)
2967 audit_log_format(audit_buf, " src_prefixlen=%d",
2968 sel->prefixlen_s);
2969 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2970 if (sel->prefixlen_d != 32)
2971 audit_log_format(audit_buf, " dst_prefixlen=%d",
2972 sel->prefixlen_d);
2973 break;
2974 case AF_INET6:
2975 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
2976 if (sel->prefixlen_s != 128)
2977 audit_log_format(audit_buf, " src_prefixlen=%d",
2978 sel->prefixlen_s);
2979 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
2980 if (sel->prefixlen_d != 128)
2981 audit_log_format(audit_buf, " dst_prefixlen=%d",
2982 sel->prefixlen_d);
2983 break;
2984 }
2985 }
2986
2987 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2988 kuid_t auid, u32 sessionid, u32 secid)
2989 {
2990 struct audit_buffer *audit_buf;
2991
2992 audit_buf = xfrm_audit_start("SPD-add");
2993 if (audit_buf == NULL)
2994 return;
2995 xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2996 audit_log_format(audit_buf, " res=%u", result);
2997 xfrm_audit_common_policyinfo(xp, audit_buf);
2998 audit_log_end(audit_buf);
2999 }
3000 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3001
3002 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3003 kuid_t auid, u32 sessionid, u32 secid)
3004 {
3005 struct audit_buffer *audit_buf;
3006
3007 audit_buf = xfrm_audit_start("SPD-delete");
3008 if (audit_buf == NULL)
3009 return;
3010 xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
3011 audit_log_format(audit_buf, " res=%u", result);
3012 xfrm_audit_common_policyinfo(xp, audit_buf);
3013 audit_log_end(audit_buf);
3014 }
3015 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3016 #endif
3017
3018 #ifdef CONFIG_XFRM_MIGRATE
3019 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3020 const struct xfrm_selector *sel_tgt)
3021 {
3022 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3023 if (sel_tgt->family == sel_cmp->family &&
3024 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3025 sel_cmp->family) &&
3026 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3027 sel_cmp->family) &&
3028 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3029 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3030 return true;
3031 }
3032 } else {
3033 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3034 return true;
3035 }
3036 }
3037 return false;
3038 }
3039
3040 static struct xfrm_policy * xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3041 u8 dir, u8 type)
3042 {
3043 struct xfrm_policy *pol, *ret = NULL;
3044 struct hlist_node *entry;
3045 struct hlist_head *chain;
3046 u32 priority = ~0U;
3047
3048 read_lock_bh(&xfrm_policy_lock);
3049 chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir);
3050 hlist_for_each_entry(pol, entry, chain, bydst) {
3051 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3052 pol->type == type) {
3053 ret = pol;
3054 priority = ret->priority;
3055 break;
3056 }
3057 }
3058 chain = &init_net.xfrm.policy_inexact[dir];
3059 hlist_for_each_entry(pol, entry, chain, bydst) {
3060 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3061 pol->type == type &&
3062 pol->priority < priority) {
3063 ret = pol;
3064 break;
3065 }
3066 }
3067
3068 if (ret)
3069 xfrm_pol_hold(ret);
3070
3071 read_unlock_bh(&xfrm_policy_lock);
3072
3073 return ret;
3074 }
3075
3076 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3077 {
3078 int match = 0;
3079
3080 if (t->mode == m->mode && t->id.proto == m->proto &&
3081 (m->reqid == 0 || t->reqid == m->reqid)) {
3082 switch (t->mode) {
3083 case XFRM_MODE_TUNNEL:
3084 case XFRM_MODE_BEET:
3085 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3086 m->old_family) &&
3087 xfrm_addr_equal(&t->saddr, &m->old_saddr,
3088 m->old_family)) {
3089 match = 1;
3090 }
3091 break;
3092 case XFRM_MODE_TRANSPORT:
3093 /* in case of transport mode, template does not store
3094 any IP addresses, hence we just compare mode and
3095 protocol */
3096 match = 1;
3097 break;
3098 default:
3099 break;
3100 }
3101 }
3102 return match;
3103 }
3104
3105 /* update endpoint address(es) of template(s) */
3106 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3107 struct xfrm_migrate *m, int num_migrate)
3108 {
3109 struct xfrm_migrate *mp;
3110 int i, j, n = 0;
3111
3112 write_lock_bh(&pol->lock);
3113 if (unlikely(pol->walk.dead)) {
3114 /* target policy has been deleted */
3115 write_unlock_bh(&pol->lock);
3116 return -ENOENT;
3117 }
3118
3119 for (i = 0; i < pol->xfrm_nr; i++) {
3120 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3121 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3122 continue;
3123 n++;
3124 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3125 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3126 continue;
3127 /* update endpoints */
3128 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3129 sizeof(pol->xfrm_vec[i].id.daddr));
3130 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3131 sizeof(pol->xfrm_vec[i].saddr));
3132 pol->xfrm_vec[i].encap_family = mp->new_family;
3133 /* flush bundles */
3134 atomic_inc(&pol->genid);
3135 }
3136 }
3137
3138 write_unlock_bh(&pol->lock);
3139
3140 if (!n)
3141 return -ENODATA;
3142
3143 return 0;
3144 }
3145
3146 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3147 {
3148 int i, j;
3149
3150 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3151 return -EINVAL;
3152
3153 for (i = 0; i < num_migrate; i++) {
3154 if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3155 m[i].old_family) &&
3156 xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3157 m[i].old_family))
3158 return -EINVAL;
3159 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3160 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3161 return -EINVAL;
3162
3163 /* check if there is any duplicated entry */
3164 for (j = i + 1; j < num_migrate; j++) {
3165 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3166 sizeof(m[i].old_daddr)) &&
3167 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3168 sizeof(m[i].old_saddr)) &&
3169 m[i].proto == m[j].proto &&
3170 m[i].mode == m[j].mode &&
3171 m[i].reqid == m[j].reqid &&
3172 m[i].old_family == m[j].old_family)
3173 return -EINVAL;
3174 }
3175 }
3176
3177 return 0;
3178 }
3179
3180 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3181 struct xfrm_migrate *m, int num_migrate,
3182 struct xfrm_kmaddress *k)
3183 {
3184 int i, err, nx_cur = 0, nx_new = 0;
3185 struct xfrm_policy *pol = NULL;
3186 struct xfrm_state *x, *xc;
3187 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3188 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3189 struct xfrm_migrate *mp;
3190
3191 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3192 goto out;
3193
3194 /* Stage 1 - find policy */
3195 if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
3196 err = -ENOENT;
3197 goto out;
3198 }
3199
3200 /* Stage 2 - find and update state(s) */
3201 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3202 if ((x = xfrm_migrate_state_find(mp))) {
3203 x_cur[nx_cur] = x;
3204 nx_cur++;
3205 if ((xc = xfrm_state_migrate(x, mp))) {
3206 x_new[nx_new] = xc;
3207 nx_new++;
3208 } else {
3209 err = -ENODATA;
3210 goto restore_state;
3211 }
3212 }
3213 }
3214
3215 /* Stage 3 - update policy */
3216 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3217 goto restore_state;
3218
3219 /* Stage 4 - delete old state(s) */
3220 if (nx_cur) {
3221 xfrm_states_put(x_cur, nx_cur);
3222 xfrm_states_delete(x_cur, nx_cur);
3223 }
3224
3225 /* Stage 5 - announce */
3226 km_migrate(sel, dir, type, m, num_migrate, k);
3227
3228 xfrm_pol_put(pol);
3229
3230 return 0;
3231 out:
3232 return err;
3233
3234 restore_state:
3235 if (pol)
3236 xfrm_pol_put(pol);
3237 if (nx_cur)
3238 xfrm_states_put(x_cur, nx_cur);
3239 if (nx_new)
3240 xfrm_states_delete(x_new, nx_new);
3241
3242 return err;
3243 }
3244 EXPORT_SYMBOL(xfrm_migrate);
3245 #endif
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