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io_uring: ensure finish_wait() is always called in __io_uring_task_cancel()
[linux/fpc-iii.git] / net / xfrm / xfrm_policy.c
blobd622c2548d2295c0893b1b5fcbd84862f95fb8ea
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * xfrm_policy.c
4 *
5 * Changes:
6 * Mitsuru KANDA @USAGI
7 * Kazunori MIYAZAWA @USAGI
8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
9 * IPv6 support
10 * Kazunori MIYAZAWA @USAGI
11 * YOSHIFUJI Hideaki
12 * Split up af-specific portion
13 * Derek Atkins <derek@ihtfp.com> Add the post_input processor
14 *
15 */
16
17 #include <linux/err.h>
18 #include <linux/slab.h>
19 #include <linux/kmod.h>
20 #include <linux/list.h>
21 #include <linux/spinlock.h>
22 #include <linux/workqueue.h>
23 #include <linux/notifier.h>
24 #include <linux/netdevice.h>
25 #include <linux/netfilter.h>
26 #include <linux/module.h>
27 #include <linux/cache.h>
28 #include <linux/cpu.h>
29 #include <linux/audit.h>
30 #include <linux/rhashtable.h>
31 #include <linux/if_tunnel.h>
32 #include <net/dst.h>
33 #include <net/flow.h>
34 #include <net/xfrm.h>
35 #include <net/ip.h>
36 #if IS_ENABLED(CONFIG_IPV6_MIP6)
37 #include <net/mip6.h>
38 #endif
39 #ifdef CONFIG_XFRM_STATISTICS
40 #include <net/snmp.h>
41 #endif
42 #ifdef CONFIG_XFRM_ESPINTCP
43 #include <net/espintcp.h>
44 #endif
45
46 #include "xfrm_hash.h"
47
48 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
49 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
50 #define XFRM_MAX_QUEUE_LEN 100
51
52 struct xfrm_flo {
53 struct dst_entry *dst_orig;
54 u8 flags;
55 };
56
57 /* prefixes smaller than this are stored in lists, not trees. */
58 #define INEXACT_PREFIXLEN_IPV4 16
59 #define INEXACT_PREFIXLEN_IPV6 48
60
61 struct xfrm_pol_inexact_node {
62 struct rb_node node;
63 union {
64 xfrm_address_t addr;
65 struct rcu_head rcu;
66 };
67 u8 prefixlen;
68
69 struct rb_root root;
70
71 /* the policies matching this node, can be empty list */
72 struct hlist_head hhead;
73 };
74
75 /* xfrm inexact policy search tree:
76 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
77 * |
78 * +---- root_d: sorted by daddr:prefix
79 * | |
80 * | xfrm_pol_inexact_node
81 * | |
82 * | +- root: sorted by saddr/prefix
83 * | | |
84 * | | xfrm_pol_inexact_node
85 * | | |
86 * | | + root: unused
87 * | | |
88 * | | + hhead: saddr:daddr policies
89 * | |
90 * | +- coarse policies and all any:daddr policies
91 * |
92 * +---- root_s: sorted by saddr:prefix
93 * | |
94 * | xfrm_pol_inexact_node
95 * | |
96 * | + root: unused
97 * | |
98 * | + hhead: saddr:any policies
99 * |
100 * +---- coarse policies and all any:any policies
101 *
102 * Lookups return four candidate lists:
103 * 1. any:any list from top-level xfrm_pol_inexact_bin
104 * 2. any:daddr list from daddr tree
105 * 3. saddr:daddr list from 2nd level daddr tree
106 * 4. saddr:any list from saddr tree
107 *
108 * This result set then needs to be searched for the policy with
109 * the lowest priority. If two results have same prio, youngest one wins.
110 */
111
112 struct xfrm_pol_inexact_key {
113 possible_net_t net;
114 u32 if_id;
115 u16 family;
116 u8 dir, type;
117 };
118
119 struct xfrm_pol_inexact_bin {
120 struct xfrm_pol_inexact_key k;
121 struct rhash_head head;
122 /* list containing '*:*' policies */
123 struct hlist_head hhead;
124
125 seqcount_spinlock_t count;
126 /* tree sorted by daddr/prefix */
127 struct rb_root root_d;
128
129 /* tree sorted by saddr/prefix */
130 struct rb_root root_s;
131
132 /* slow path below */
133 struct list_head inexact_bins;
134 struct rcu_head rcu;
135 };
136
137 enum xfrm_pol_inexact_candidate_type {
138 XFRM_POL_CAND_BOTH,
139 XFRM_POL_CAND_SADDR,
140 XFRM_POL_CAND_DADDR,
141 XFRM_POL_CAND_ANY,
142
143 XFRM_POL_CAND_MAX,
144 };
145
146 struct xfrm_pol_inexact_candidates {
147 struct hlist_head *res[XFRM_POL_CAND_MAX];
148 };
149
150 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
151 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
152
153 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
154 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
155 __read_mostly;
156
157 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
158 static __read_mostly seqcount_mutex_t xfrm_policy_hash_generation;
159
160 static struct rhashtable xfrm_policy_inexact_table;
161 static const struct rhashtable_params xfrm_pol_inexact_params;
162
163 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
164 static int stale_bundle(struct dst_entry *dst);
165 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
166 static void xfrm_policy_queue_process(struct timer_list *t);
167
168 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
169 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
170 int dir);
171
172 static struct xfrm_pol_inexact_bin *
173 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
174 u32 if_id);
175
176 static struct xfrm_pol_inexact_bin *
177 xfrm_policy_inexact_lookup_rcu(struct net *net,
178 u8 type, u16 family, u8 dir, u32 if_id);
179 static struct xfrm_policy *
180 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
181 bool excl);
182 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
183 struct xfrm_policy *policy);
184
185 static bool
186 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
187 struct xfrm_pol_inexact_bin *b,
188 const xfrm_address_t *saddr,
189 const xfrm_address_t *daddr);
190
191 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
192 {
193 return refcount_inc_not_zero(&policy->refcnt);
194 }
195
196 static inline bool
197 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
198 {
199 const struct flowi4 *fl4 = &fl->u.ip4;
200
201 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
202 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
203 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
204 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
205 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
206 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
207 }
208
209 static inline bool
210 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
211 {
212 const struct flowi6 *fl6 = &fl->u.ip6;
213
214 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
215 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
216 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
217 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
218 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
219 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
220 }
221
222 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
223 unsigned short family)
224 {
225 switch (family) {
226 case AF_INET:
227 return __xfrm4_selector_match(sel, fl);
228 case AF_INET6:
229 return __xfrm6_selector_match(sel, fl);
230 }
231 return false;
232 }
233
234 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
235 {
236 const struct xfrm_policy_afinfo *afinfo;
237
238 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
239 return NULL;
240 rcu_read_lock();
241 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
242 if (unlikely(!afinfo))
243 rcu_read_unlock();
244 return afinfo;
245 }
246
247 /* Called with rcu_read_lock(). */
248 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
249 {
250 return rcu_dereference(xfrm_if_cb);
251 }
252
253 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
254 const xfrm_address_t *saddr,
255 const xfrm_address_t *daddr,
256 int family, u32 mark)
257 {
258 const struct xfrm_policy_afinfo *afinfo;
259 struct dst_entry *dst;
260
261 afinfo = xfrm_policy_get_afinfo(family);
262 if (unlikely(afinfo == NULL))
263 return ERR_PTR(-EAFNOSUPPORT);
264
265 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
266
267 rcu_read_unlock();
268
269 return dst;
270 }
271 EXPORT_SYMBOL(__xfrm_dst_lookup);
272
273 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
274 int tos, int oif,
275 xfrm_address_t *prev_saddr,
276 xfrm_address_t *prev_daddr,
277 int family, u32 mark)
278 {
279 struct net *net = xs_net(x);
280 xfrm_address_t *saddr = &x->props.saddr;
281 xfrm_address_t *daddr = &x->id.daddr;
282 struct dst_entry *dst;
283
284 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
285 saddr = x->coaddr;
286 daddr = prev_daddr;
287 }
288 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
289 saddr = prev_saddr;
290 daddr = x->coaddr;
291 }
292
293 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
294
295 if (!IS_ERR(dst)) {
296 if (prev_saddr != saddr)
297 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
298 if (prev_daddr != daddr)
299 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
300 }
301
302 return dst;
303 }
304
305 static inline unsigned long make_jiffies(long secs)
306 {
307 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
308 return MAX_SCHEDULE_TIMEOUT-1;
309 else
310 return secs*HZ;
311 }
312
313 static void xfrm_policy_timer(struct timer_list *t)
314 {
315 struct xfrm_policy *xp = from_timer(xp, t, timer);
316 time64_t now = ktime_get_real_seconds();
317 time64_t next = TIME64_MAX;
318 int warn = 0;
319 int dir;
320
321 read_lock(&xp->lock);
322
323 if (unlikely(xp->walk.dead))
324 goto out;
325
326 dir = xfrm_policy_id2dir(xp->index);
327
328 if (xp->lft.hard_add_expires_seconds) {
329 time64_t tmo = xp->lft.hard_add_expires_seconds +
330 xp->curlft.add_time - now;
331 if (tmo <= 0)
332 goto expired;
333 if (tmo < next)
334 next = tmo;
335 }
336 if (xp->lft.hard_use_expires_seconds) {
337 time64_t tmo = xp->lft.hard_use_expires_seconds +
338 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
339 if (tmo <= 0)
340 goto expired;
341 if (tmo < next)
342 next = tmo;
343 }
344 if (xp->lft.soft_add_expires_seconds) {
345 time64_t tmo = xp->lft.soft_add_expires_seconds +
346 xp->curlft.add_time - now;
347 if (tmo <= 0) {
348 warn = 1;
349 tmo = XFRM_KM_TIMEOUT;
350 }
351 if (tmo < next)
352 next = tmo;
353 }
354 if (xp->lft.soft_use_expires_seconds) {
355 time64_t tmo = xp->lft.soft_use_expires_seconds +
356 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
357 if (tmo <= 0) {
358 warn = 1;
359 tmo = XFRM_KM_TIMEOUT;
360 }
361 if (tmo < next)
362 next = tmo;
363 }
364
365 if (warn)
366 km_policy_expired(xp, dir, 0, 0);
367 if (next != TIME64_MAX &&
368 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
369 xfrm_pol_hold(xp);
370
371 out:
372 read_unlock(&xp->lock);
373 xfrm_pol_put(xp);
374 return;
375
376 expired:
377 read_unlock(&xp->lock);
378 if (!xfrm_policy_delete(xp, dir))
379 km_policy_expired(xp, dir, 1, 0);
380 xfrm_pol_put(xp);
381 }
382
383 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
384 * SPD calls.
385 */
386
387 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
388 {
389 struct xfrm_policy *policy;
390
391 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
392
393 if (policy) {
394 write_pnet(&policy->xp_net, net);
395 INIT_LIST_HEAD(&policy->walk.all);
396 INIT_HLIST_NODE(&policy->bydst_inexact_list);
397 INIT_HLIST_NODE(&policy->bydst);
398 INIT_HLIST_NODE(&policy->byidx);
399 rwlock_init(&policy->lock);
400 refcount_set(&policy->refcnt, 1);
401 skb_queue_head_init(&policy->polq.hold_queue);
402 timer_setup(&policy->timer, xfrm_policy_timer, 0);
403 timer_setup(&policy->polq.hold_timer,
404 xfrm_policy_queue_process, 0);
405 }
406 return policy;
407 }
408 EXPORT_SYMBOL(xfrm_policy_alloc);
409
410 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
411 {
412 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
413
414 security_xfrm_policy_free(policy->security);
415 kfree(policy);
416 }
417
418 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
419
420 void xfrm_policy_destroy(struct xfrm_policy *policy)
421 {
422 BUG_ON(!policy->walk.dead);
423
424 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
425 BUG();
426
427 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
428 }
429 EXPORT_SYMBOL(xfrm_policy_destroy);
430
431 /* Rule must be locked. Release descendant resources, announce
432 * entry dead. The rule must be unlinked from lists to the moment.
433 */
434
435 static void xfrm_policy_kill(struct xfrm_policy *policy)
436 {
437 write_lock_bh(&policy->lock);
438 policy->walk.dead = 1;
439 write_unlock_bh(&policy->lock);
440
441 atomic_inc(&policy->genid);
442
443 if (del_timer(&policy->polq.hold_timer))
444 xfrm_pol_put(policy);
445 skb_queue_purge(&policy->polq.hold_queue);
446
447 if (del_timer(&policy->timer))
448 xfrm_pol_put(policy);
449
450 xfrm_pol_put(policy);
451 }
452
453 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
454
455 static inline unsigned int idx_hash(struct net *net, u32 index)
456 {
457 return __idx_hash(index, net->xfrm.policy_idx_hmask);
458 }
459
460 /* calculate policy hash thresholds */
461 static void __get_hash_thresh(struct net *net,
462 unsigned short family, int dir,
463 u8 *dbits, u8 *sbits)
464 {
465 switch (family) {
466 case AF_INET:
467 *dbits = net->xfrm.policy_bydst[dir].dbits4;
468 *sbits = net->xfrm.policy_bydst[dir].sbits4;
469 break;
470
471 case AF_INET6:
472 *dbits = net->xfrm.policy_bydst[dir].dbits6;
473 *sbits = net->xfrm.policy_bydst[dir].sbits6;
474 break;
475
476 default:
477 *dbits = 0;
478 *sbits = 0;
479 }
480 }
481
482 static struct hlist_head *policy_hash_bysel(struct net *net,
483 const struct xfrm_selector *sel,
484 unsigned short family, int dir)
485 {
486 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
487 unsigned int hash;
488 u8 dbits;
489 u8 sbits;
490
491 __get_hash_thresh(net, family, dir, &dbits, &sbits);
492 hash = __sel_hash(sel, family, hmask, dbits, sbits);
493
494 if (hash == hmask + 1)
495 return NULL;
496
497 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
498 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
499 }
500
501 static struct hlist_head *policy_hash_direct(struct net *net,
502 const xfrm_address_t *daddr,
503 const xfrm_address_t *saddr,
504 unsigned short family, int dir)
505 {
506 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
507 unsigned int hash;
508 u8 dbits;
509 u8 sbits;
510
511 __get_hash_thresh(net, family, dir, &dbits, &sbits);
512 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
513
514 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
515 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
516 }
517
518 static void xfrm_dst_hash_transfer(struct net *net,
519 struct hlist_head *list,
520 struct hlist_head *ndsttable,
521 unsigned int nhashmask,
522 int dir)
523 {
524 struct hlist_node *tmp, *entry0 = NULL;
525 struct xfrm_policy *pol;
526 unsigned int h0 = 0;
527 u8 dbits;
528 u8 sbits;
529
530 redo:
531 hlist_for_each_entry_safe(pol, tmp, list, bydst) {
532 unsigned int h;
533
534 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
535 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
536 pol->family, nhashmask, dbits, sbits);
537 if (!entry0) {
538 hlist_del_rcu(&pol->bydst);
539 hlist_add_head_rcu(&pol->bydst, ndsttable + h);
540 h0 = h;
541 } else {
542 if (h != h0)
543 continue;
544 hlist_del_rcu(&pol->bydst);
545 hlist_add_behind_rcu(&pol->bydst, entry0);
546 }
547 entry0 = &pol->bydst;
548 }
549 if (!hlist_empty(list)) {
550 entry0 = NULL;
551 goto redo;
552 }
553 }
554
555 static void xfrm_idx_hash_transfer(struct hlist_head *list,
556 struct hlist_head *nidxtable,
557 unsigned int nhashmask)
558 {
559 struct hlist_node *tmp;
560 struct xfrm_policy *pol;
561
562 hlist_for_each_entry_safe(pol, tmp, list, byidx) {
563 unsigned int h;
564
565 h = __idx_hash(pol->index, nhashmask);
566 hlist_add_head(&pol->byidx, nidxtable+h);
567 }
568 }
569
570 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
571 {
572 return ((old_hmask + 1) << 1) - 1;
573 }
574
575 static void xfrm_bydst_resize(struct net *net, int dir)
576 {
577 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
578 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
579 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
580 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
581 struct hlist_head *odst;
582 int i;
583
584 if (!ndst)
585 return;
586
587 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
588 write_seqcount_begin(&xfrm_policy_hash_generation);
589
590 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
591 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
592
593 for (i = hmask; i >= 0; i--)
594 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
595
596 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
597 net->xfrm.policy_bydst[dir].hmask = nhashmask;
598
599 write_seqcount_end(&xfrm_policy_hash_generation);
600 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
601
602 synchronize_rcu();
603
604 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
605 }
606
607 static void xfrm_byidx_resize(struct net *net, int total)
608 {
609 unsigned int hmask = net->xfrm.policy_idx_hmask;
610 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
611 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
612 struct hlist_head *oidx = net->xfrm.policy_byidx;
613 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
614 int i;
615
616 if (!nidx)
617 return;
618
619 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
620
621 for (i = hmask; i >= 0; i--)
622 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
623
624 net->xfrm.policy_byidx = nidx;
625 net->xfrm.policy_idx_hmask = nhashmask;
626
627 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
628
629 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
630 }
631
632 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
633 {
634 unsigned int cnt = net->xfrm.policy_count[dir];
635 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
636
637 if (total)
638 *total += cnt;
639
640 if ((hmask + 1) < xfrm_policy_hashmax &&
641 cnt > hmask)
642 return 1;
643
644 return 0;
645 }
646
647 static inline int xfrm_byidx_should_resize(struct net *net, int total)
648 {
649 unsigned int hmask = net->xfrm.policy_idx_hmask;
650
651 if ((hmask + 1) < xfrm_policy_hashmax &&
652 total > hmask)
653 return 1;
654
655 return 0;
656 }
657
658 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
659 {
660 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
661 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
662 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
663 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
664 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
665 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
666 si->spdhcnt = net->xfrm.policy_idx_hmask;
667 si->spdhmcnt = xfrm_policy_hashmax;
668 }
669 EXPORT_SYMBOL(xfrm_spd_getinfo);
670
671 static DEFINE_MUTEX(hash_resize_mutex);
672 static void xfrm_hash_resize(struct work_struct *work)
673 {
674 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
675 int dir, total;
676
677 mutex_lock(&hash_resize_mutex);
678
679 total = 0;
680 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
681 if (xfrm_bydst_should_resize(net, dir, &total))
682 xfrm_bydst_resize(net, dir);
683 }
684 if (xfrm_byidx_should_resize(net, total))
685 xfrm_byidx_resize(net, total);
686
687 mutex_unlock(&hash_resize_mutex);
688 }
689
690 /* Make sure *pol can be inserted into fastbin.
691 * Useful to check that later insert requests will be sucessful
692 * (provided xfrm_policy_lock is held throughout).
693 */
694 static struct xfrm_pol_inexact_bin *
695 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
696 {
697 struct xfrm_pol_inexact_bin *bin, *prev;
698 struct xfrm_pol_inexact_key k = {
699 .family = pol->family,
700 .type = pol->type,
701 .dir = dir,
702 .if_id = pol->if_id,
703 };
704 struct net *net = xp_net(pol);
705
706 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
707
708 write_pnet(&k.net, net);
709 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
710 xfrm_pol_inexact_params);
711 if (bin)
712 return bin;
713
714 bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
715 if (!bin)
716 return NULL;
717
718 bin->k = k;
719 INIT_HLIST_HEAD(&bin->hhead);
720 bin->root_d = RB_ROOT;
721 bin->root_s = RB_ROOT;
722 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
723
724 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
725 &bin->k, &bin->head,
726 xfrm_pol_inexact_params);
727 if (!prev) {
728 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
729 return bin;
730 }
731
732 kfree(bin);
733
734 return IS_ERR(prev) ? NULL : prev;
735 }
736
737 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
738 int family, u8 prefixlen)
739 {
740 if (xfrm_addr_any(addr, family))
741 return true;
742
743 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
744 return true;
745
746 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
747 return true;
748
749 return false;
750 }
751
752 static bool
753 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
754 {
755 const xfrm_address_t *addr;
756 bool saddr_any, daddr_any;
757 u8 prefixlen;
758
759 addr = &policy->selector.saddr;
760 prefixlen = policy->selector.prefixlen_s;
761
762 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
763 policy->family,
764 prefixlen);
765 addr = &policy->selector.daddr;
766 prefixlen = policy->selector.prefixlen_d;
767 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
768 policy->family,
769 prefixlen);
770 return saddr_any && daddr_any;
771 }
772
773 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
774 const xfrm_address_t *addr, u8 prefixlen)
775 {
776 node->addr = *addr;
777 node->prefixlen = prefixlen;
778 }
779
780 static struct xfrm_pol_inexact_node *
781 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
782 {
783 struct xfrm_pol_inexact_node *node;
784
785 node = kzalloc(sizeof(*node), GFP_ATOMIC);
786 if (node)
787 xfrm_pol_inexact_node_init(node, addr, prefixlen);
788
789 return node;
790 }
791
792 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
793 const xfrm_address_t *b,
794 u8 prefixlen, u16 family)
795 {
796 unsigned int pdw, pbi;
797 int delta = 0;
798
799 switch (family) {
800 case AF_INET:
801 if (sizeof(long) == 4 && prefixlen == 0)
802 return ntohl(a->a4) - ntohl(b->a4);
803 return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) -
804 (ntohl(b->a4) & ((~0UL << (32 - prefixlen))));
805 case AF_INET6:
806 pdw = prefixlen >> 5;
807 pbi = prefixlen & 0x1f;
808
809 if (pdw) {
810 delta = memcmp(a->a6, b->a6, pdw << 2);
811 if (delta)
812 return delta;
813 }
814 if (pbi) {
815 u32 mask = ~0u << (32 - pbi);
816
817 delta = (ntohl(a->a6[pdw]) & mask) -
818 (ntohl(b->a6[pdw]) & mask);
819 }
820 break;
821 default:
822 break;
823 }
824
825 return delta;
826 }
827
828 static void xfrm_policy_inexact_list_reinsert(struct net *net,
829 struct xfrm_pol_inexact_node *n,
830 u16 family)
831 {
832 unsigned int matched_s, matched_d;
833 struct xfrm_policy *policy, *p;
834
835 matched_s = 0;
836 matched_d = 0;
837
838 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
839 struct hlist_node *newpos = NULL;
840 bool matches_s, matches_d;
841
842 if (!policy->bydst_reinsert)
843 continue;
844
845 WARN_ON_ONCE(policy->family != family);
846
847 policy->bydst_reinsert = false;
848 hlist_for_each_entry(p, &n->hhead, bydst) {
849 if (policy->priority > p->priority)
850 newpos = &p->bydst;
851 else if (policy->priority == p->priority &&
852 policy->pos > p->pos)
853 newpos = &p->bydst;
854 else
855 break;
856 }
857
858 if (newpos)
859 hlist_add_behind_rcu(&policy->bydst, newpos);
860 else
861 hlist_add_head_rcu(&policy->bydst, &n->hhead);
862
863 /* paranoia checks follow.
864 * Check that the reinserted policy matches at least
865 * saddr or daddr for current node prefix.
866 *
867 * Matching both is fine, matching saddr in one policy
868 * (but not daddr) and then matching only daddr in another
869 * is a bug.
870 */
871 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
872 &n->addr,
873 n->prefixlen,
874 family) == 0;
875 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
876 &n->addr,
877 n->prefixlen,
878 family) == 0;
879 if (matches_s && matches_d)
880 continue;
881
882 WARN_ON_ONCE(!matches_s && !matches_d);
883 if (matches_s)
884 matched_s++;
885 if (matches_d)
886 matched_d++;
887 WARN_ON_ONCE(matched_s && matched_d);
888 }
889 }
890
891 static void xfrm_policy_inexact_node_reinsert(struct net *net,
892 struct xfrm_pol_inexact_node *n,
893 struct rb_root *new,
894 u16 family)
895 {
896 struct xfrm_pol_inexact_node *node;
897 struct rb_node **p, *parent;
898
899 /* we should not have another subtree here */
900 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
901 restart:
902 parent = NULL;
903 p = &new->rb_node;
904 while (*p) {
905 u8 prefixlen;
906 int delta;
907
908 parent = *p;
909 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
910
911 prefixlen = min(node->prefixlen, n->prefixlen);
912
913 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
914 prefixlen, family);
915 if (delta < 0) {
916 p = &parent->rb_left;
917 } else if (delta > 0) {
918 p = &parent->rb_right;
919 } else {
920 bool same_prefixlen = node->prefixlen == n->prefixlen;
921 struct xfrm_policy *tmp;
922
923 hlist_for_each_entry(tmp, &n->hhead, bydst) {
924 tmp->bydst_reinsert = true;
925 hlist_del_rcu(&tmp->bydst);
926 }
927
928 node->prefixlen = prefixlen;
929
930 xfrm_policy_inexact_list_reinsert(net, node, family);
931
932 if (same_prefixlen) {
933 kfree_rcu(n, rcu);
934 return;
935 }
936
937 rb_erase(*p, new);
938 kfree_rcu(n, rcu);
939 n = node;
940 goto restart;
941 }
942 }
943
944 rb_link_node_rcu(&n->node, parent, p);
945 rb_insert_color(&n->node, new);
946 }
947
948 /* merge nodes v and n */
949 static void xfrm_policy_inexact_node_merge(struct net *net,
950 struct xfrm_pol_inexact_node *v,
951 struct xfrm_pol_inexact_node *n,
952 u16 family)
953 {
954 struct xfrm_pol_inexact_node *node;
955 struct xfrm_policy *tmp;
956 struct rb_node *rnode;
957
958 /* To-be-merged node v has a subtree.
959 *
960 * Dismantle it and insert its nodes to n->root.
961 */
962 while ((rnode = rb_first(&v->root)) != NULL) {
963 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
964 rb_erase(&node->node, &v->root);
965 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
966 family);
967 }
968
969 hlist_for_each_entry(tmp, &v->hhead, bydst) {
970 tmp->bydst_reinsert = true;
971 hlist_del_rcu(&tmp->bydst);
972 }
973
974 xfrm_policy_inexact_list_reinsert(net, n, family);
975 }
976
977 static struct xfrm_pol_inexact_node *
978 xfrm_policy_inexact_insert_node(struct net *net,
979 struct rb_root *root,
980 xfrm_address_t *addr,
981 u16 family, u8 prefixlen, u8 dir)
982 {
983 struct xfrm_pol_inexact_node *cached = NULL;
984 struct rb_node **p, *parent = NULL;
985 struct xfrm_pol_inexact_node *node;
986
987 p = &root->rb_node;
988 while (*p) {
989 int delta;
990
991 parent = *p;
992 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
993
994 delta = xfrm_policy_addr_delta(addr, &node->addr,
995 node->prefixlen,
996 family);
997 if (delta == 0 && prefixlen >= node->prefixlen) {
998 WARN_ON_ONCE(cached); /* ipsec policies got lost */
999 return node;
1000 }
1001
1002 if (delta < 0)
1003 p = &parent->rb_left;
1004 else
1005 p = &parent->rb_right;
1006
1007 if (prefixlen < node->prefixlen) {
1008 delta = xfrm_policy_addr_delta(addr, &node->addr,
1009 prefixlen,
1010 family);
1011 if (delta)
1012 continue;
1013
1014 /* This node is a subnet of the new prefix. It needs
1015 * to be removed and re-inserted with the smaller
1016 * prefix and all nodes that are now also covered
1017 * by the reduced prefixlen.
1018 */
1019 rb_erase(&node->node, root);
1020
1021 if (!cached) {
1022 xfrm_pol_inexact_node_init(node, addr,
1023 prefixlen);
1024 cached = node;
1025 } else {
1026 /* This node also falls within the new
1027 * prefixlen. Merge the to-be-reinserted
1028 * node and this one.
1029 */
1030 xfrm_policy_inexact_node_merge(net, node,
1031 cached, family);
1032 kfree_rcu(node, rcu);
1033 }
1034
1035 /* restart */
1036 p = &root->rb_node;
1037 parent = NULL;
1038 }
1039 }
1040
1041 node = cached;
1042 if (!node) {
1043 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1044 if (!node)
1045 return NULL;
1046 }
1047
1048 rb_link_node_rcu(&node->node, parent, p);
1049 rb_insert_color(&node->node, root);
1050
1051 return node;
1052 }
1053
1054 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1055 {
1056 struct xfrm_pol_inexact_node *node;
1057 struct rb_node *rn = rb_first(r);
1058
1059 while (rn) {
1060 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1061
1062 xfrm_policy_inexact_gc_tree(&node->root, rm);
1063 rn = rb_next(rn);
1064
1065 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1066 WARN_ON_ONCE(rm);
1067 continue;
1068 }
1069
1070 rb_erase(&node->node, r);
1071 kfree_rcu(node, rcu);
1072 }
1073 }
1074
1075 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1076 {
1077 write_seqcount_begin(&b->count);
1078 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1079 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1080 write_seqcount_end(&b->count);
1081
1082 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1083 !hlist_empty(&b->hhead)) {
1084 WARN_ON_ONCE(net_exit);
1085 return;
1086 }
1087
1088 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1089 xfrm_pol_inexact_params) == 0) {
1090 list_del(&b->inexact_bins);
1091 kfree_rcu(b, rcu);
1092 }
1093 }
1094
1095 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1096 {
1097 struct net *net = read_pnet(&b->k.net);
1098
1099 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1100 __xfrm_policy_inexact_prune_bin(b, false);
1101 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1102 }
1103
1104 static void __xfrm_policy_inexact_flush(struct net *net)
1105 {
1106 struct xfrm_pol_inexact_bin *bin, *t;
1107
1108 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1109
1110 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1111 __xfrm_policy_inexact_prune_bin(bin, false);
1112 }
1113
1114 static struct hlist_head *
1115 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1116 struct xfrm_policy *policy, u8 dir)
1117 {
1118 struct xfrm_pol_inexact_node *n;
1119 struct net *net;
1120
1121 net = xp_net(policy);
1122 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1123
1124 if (xfrm_policy_inexact_insert_use_any_list(policy))
1125 return &bin->hhead;
1126
1127 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1128 policy->family,
1129 policy->selector.prefixlen_d)) {
1130 write_seqcount_begin(&bin->count);
1131 n = xfrm_policy_inexact_insert_node(net,
1132 &bin->root_s,
1133 &policy->selector.saddr,
1134 policy->family,
1135 policy->selector.prefixlen_s,
1136 dir);
1137 write_seqcount_end(&bin->count);
1138 if (!n)
1139 return NULL;
1140
1141 return &n->hhead;
1142 }
1143
1144 /* daddr is fixed */
1145 write_seqcount_begin(&bin->count);
1146 n = xfrm_policy_inexact_insert_node(net,
1147 &bin->root_d,
1148 &policy->selector.daddr,
1149 policy->family,
1150 policy->selector.prefixlen_d, dir);
1151 write_seqcount_end(&bin->count);
1152 if (!n)
1153 return NULL;
1154
1155 /* saddr is wildcard */
1156 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1157 policy->family,
1158 policy->selector.prefixlen_s))
1159 return &n->hhead;
1160
1161 write_seqcount_begin(&bin->count);
1162 n = xfrm_policy_inexact_insert_node(net,
1163 &n->root,
1164 &policy->selector.saddr,
1165 policy->family,
1166 policy->selector.prefixlen_s, dir);
1167 write_seqcount_end(&bin->count);
1168 if (!n)
1169 return NULL;
1170
1171 return &n->hhead;
1172 }
1173
1174 static struct xfrm_policy *
1175 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1176 {
1177 struct xfrm_pol_inexact_bin *bin;
1178 struct xfrm_policy *delpol;
1179 struct hlist_head *chain;
1180 struct net *net;
1181
1182 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1183 if (!bin)
1184 return ERR_PTR(-ENOMEM);
1185
1186 net = xp_net(policy);
1187 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1188
1189 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1190 if (!chain) {
1191 __xfrm_policy_inexact_prune_bin(bin, false);
1192 return ERR_PTR(-ENOMEM);
1193 }
1194
1195 delpol = xfrm_policy_insert_list(chain, policy, excl);
1196 if (delpol && excl) {
1197 __xfrm_policy_inexact_prune_bin(bin, false);
1198 return ERR_PTR(-EEXIST);
1199 }
1200
1201 chain = &net->xfrm.policy_inexact[dir];
1202 xfrm_policy_insert_inexact_list(chain, policy);
1203
1204 if (delpol)
1205 __xfrm_policy_inexact_prune_bin(bin, false);
1206
1207 return delpol;
1208 }
1209
1210 static void xfrm_hash_rebuild(struct work_struct *work)
1211 {
1212 struct net *net = container_of(work, struct net,
1213 xfrm.policy_hthresh.work);
1214 unsigned int hmask;
1215 struct xfrm_policy *pol;
1216 struct xfrm_policy *policy;
1217 struct hlist_head *chain;
1218 struct hlist_head *odst;
1219 struct hlist_node *newpos;
1220 int i;
1221 int dir;
1222 unsigned seq;
1223 u8 lbits4, rbits4, lbits6, rbits6;
1224
1225 mutex_lock(&hash_resize_mutex);
1226
1227 /* read selector prefixlen thresholds */
1228 do {
1229 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1230
1231 lbits4 = net->xfrm.policy_hthresh.lbits4;
1232 rbits4 = net->xfrm.policy_hthresh.rbits4;
1233 lbits6 = net->xfrm.policy_hthresh.lbits6;
1234 rbits6 = net->xfrm.policy_hthresh.rbits6;
1235 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1236
1237 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1238 write_seqcount_begin(&xfrm_policy_hash_generation);
1239
1240 /* make sure that we can insert the indirect policies again before
1241 * we start with destructive action.
1242 */
1243 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1244 struct xfrm_pol_inexact_bin *bin;
1245 u8 dbits, sbits;
1246
1247 dir = xfrm_policy_id2dir(policy->index);
1248 if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1249 continue;
1250
1251 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1252 if (policy->family == AF_INET) {
1253 dbits = rbits4;
1254 sbits = lbits4;
1255 } else {
1256 dbits = rbits6;
1257 sbits = lbits6;
1258 }
1259 } else {
1260 if (policy->family == AF_INET) {
1261 dbits = lbits4;
1262 sbits = rbits4;
1263 } else {
1264 dbits = lbits6;
1265 sbits = rbits6;
1266 }
1267 }
1268
1269 if (policy->selector.prefixlen_d < dbits ||
1270 policy->selector.prefixlen_s < sbits)
1271 continue;
1272
1273 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1274 if (!bin)
1275 goto out_unlock;
1276
1277 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1278 goto out_unlock;
1279 }
1280
1281 /* reset the bydst and inexact table in all directions */
1282 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1283 struct hlist_node *n;
1284
1285 hlist_for_each_entry_safe(policy, n,
1286 &net->xfrm.policy_inexact[dir],
1287 bydst_inexact_list) {
1288 hlist_del_rcu(&policy->bydst);
1289 hlist_del_init(&policy->bydst_inexact_list);
1290 }
1291
1292 hmask = net->xfrm.policy_bydst[dir].hmask;
1293 odst = net->xfrm.policy_bydst[dir].table;
1294 for (i = hmask; i >= 0; i--) {
1295 hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1296 hlist_del_rcu(&policy->bydst);
1297 }
1298 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1299 /* dir out => dst = remote, src = local */
1300 net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1301 net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1302 net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1303 net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1304 } else {
1305 /* dir in/fwd => dst = local, src = remote */
1306 net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1307 net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1308 net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1309 net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1310 }
1311 }
1312
1313 /* re-insert all policies by order of creation */
1314 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1315 if (policy->walk.dead)
1316 continue;
1317 dir = xfrm_policy_id2dir(policy->index);
1318 if (dir >= XFRM_POLICY_MAX) {
1319 /* skip socket policies */
1320 continue;
1321 }
1322 newpos = NULL;
1323 chain = policy_hash_bysel(net, &policy->selector,
1324 policy->family, dir);
1325
1326 if (!chain) {
1327 void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1328
1329 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1330 continue;
1331 }
1332
1333 hlist_for_each_entry(pol, chain, bydst) {
1334 if (policy->priority >= pol->priority)
1335 newpos = &pol->bydst;
1336 else
1337 break;
1338 }
1339 if (newpos)
1340 hlist_add_behind_rcu(&policy->bydst, newpos);
1341 else
1342 hlist_add_head_rcu(&policy->bydst, chain);
1343 }
1344
1345 out_unlock:
1346 __xfrm_policy_inexact_flush(net);
1347 write_seqcount_end(&xfrm_policy_hash_generation);
1348 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1349
1350 mutex_unlock(&hash_resize_mutex);
1351 }
1352
1353 void xfrm_policy_hash_rebuild(struct net *net)
1354 {
1355 schedule_work(&net->xfrm.policy_hthresh.work);
1356 }
1357 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1358
1359 /* Generate new index... KAME seems to generate them ordered by cost
1360 * of an absolute inpredictability of ordering of rules. This will not pass. */
1361 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1362 {
1363 static u32 idx_generator;
1364
1365 for (;;) {
1366 struct hlist_head *list;
1367 struct xfrm_policy *p;
1368 u32 idx;
1369 int found;
1370
1371 if (!index) {
1372 idx = (idx_generator | dir);
1373 idx_generator += 8;
1374 } else {
1375 idx = index;
1376 index = 0;
1377 }
1378
1379 if (idx == 0)
1380 idx = 8;
1381 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1382 found = 0;
1383 hlist_for_each_entry(p, list, byidx) {
1384 if (p->index == idx) {
1385 found = 1;
1386 break;
1387 }
1388 }
1389 if (!found)
1390 return idx;
1391 }
1392 }
1393
1394 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1395 {
1396 u32 *p1 = (u32 *) s1;
1397 u32 *p2 = (u32 *) s2;
1398 int len = sizeof(struct xfrm_selector) / sizeof(u32);
1399 int i;
1400
1401 for (i = 0; i < len; i++) {
1402 if (p1[i] != p2[i])
1403 return 1;
1404 }
1405
1406 return 0;
1407 }
1408
1409 static void xfrm_policy_requeue(struct xfrm_policy *old,
1410 struct xfrm_policy *new)
1411 {
1412 struct xfrm_policy_queue *pq = &old->polq;
1413 struct sk_buff_head list;
1414
1415 if (skb_queue_empty(&pq->hold_queue))
1416 return;
1417
1418 __skb_queue_head_init(&list);
1419
1420 spin_lock_bh(&pq->hold_queue.lock);
1421 skb_queue_splice_init(&pq->hold_queue, &list);
1422 if (del_timer(&pq->hold_timer))
1423 xfrm_pol_put(old);
1424 spin_unlock_bh(&pq->hold_queue.lock);
1425
1426 pq = &new->polq;
1427
1428 spin_lock_bh(&pq->hold_queue.lock);
1429 skb_queue_splice(&list, &pq->hold_queue);
1430 pq->timeout = XFRM_QUEUE_TMO_MIN;
1431 if (!mod_timer(&pq->hold_timer, jiffies))
1432 xfrm_pol_hold(new);
1433 spin_unlock_bh(&pq->hold_queue.lock);
1434 }
1435
1436 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1437 struct xfrm_policy *pol)
1438 {
1439 return mark->v == pol->mark.v && mark->m == pol->mark.m;
1440 }
1441
1442 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1443 {
1444 const struct xfrm_pol_inexact_key *k = data;
1445 u32 a = k->type << 24 | k->dir << 16 | k->family;
1446
1447 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1448 seed);
1449 }
1450
1451 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1452 {
1453 const struct xfrm_pol_inexact_bin *b = data;
1454
1455 return xfrm_pol_bin_key(&b->k, 0, seed);
1456 }
1457
1458 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1459 const void *ptr)
1460 {
1461 const struct xfrm_pol_inexact_key *key = arg->key;
1462 const struct xfrm_pol_inexact_bin *b = ptr;
1463 int ret;
1464
1465 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1466 return -1;
1467
1468 ret = b->k.dir ^ key->dir;
1469 if (ret)
1470 return ret;
1471
1472 ret = b->k.type ^ key->type;
1473 if (ret)
1474 return ret;
1475
1476 ret = b->k.family ^ key->family;
1477 if (ret)
1478 return ret;
1479
1480 return b->k.if_id ^ key->if_id;
1481 }
1482
1483 static const struct rhashtable_params xfrm_pol_inexact_params = {
1484 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head),
1485 .hashfn = xfrm_pol_bin_key,
1486 .obj_hashfn = xfrm_pol_bin_obj,
1487 .obj_cmpfn = xfrm_pol_bin_cmp,
1488 .automatic_shrinking = true,
1489 };
1490
1491 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1492 struct xfrm_policy *policy)
1493 {
1494 struct xfrm_policy *pol, *delpol = NULL;
1495 struct hlist_node *newpos = NULL;
1496 int i = 0;
1497
1498 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1499 if (pol->type == policy->type &&
1500 pol->if_id == policy->if_id &&
1501 !selector_cmp(&pol->selector, &policy->selector) &&
1502 xfrm_policy_mark_match(&policy->mark, pol) &&
1503 xfrm_sec_ctx_match(pol->security, policy->security) &&
1504 !WARN_ON(delpol)) {
1505 delpol = pol;
1506 if (policy->priority > pol->priority)
1507 continue;
1508 } else if (policy->priority >= pol->priority) {
1509 newpos = &pol->bydst_inexact_list;
1510 continue;
1511 }
1512 if (delpol)
1513 break;
1514 }
1515
1516 if (newpos)
1517 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1518 else
1519 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1520
1521 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1522 pol->pos = i;
1523 i++;
1524 }
1525 }
1526
1527 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1528 struct xfrm_policy *policy,
1529 bool excl)
1530 {
1531 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1532
1533 hlist_for_each_entry(pol, chain, bydst) {
1534 if (pol->type == policy->type &&
1535 pol->if_id == policy->if_id &&
1536 !selector_cmp(&pol->selector, &policy->selector) &&
1537 xfrm_policy_mark_match(&policy->mark, pol) &&
1538 xfrm_sec_ctx_match(pol->security, policy->security) &&
1539 !WARN_ON(delpol)) {
1540 if (excl)
1541 return ERR_PTR(-EEXIST);
1542 delpol = pol;
1543 if (policy->priority > pol->priority)
1544 continue;
1545 } else if (policy->priority >= pol->priority) {
1546 newpos = pol;
1547 continue;
1548 }
1549 if (delpol)
1550 break;
1551 }
1552
1553 if (newpos)
1554 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1555 else
1556 hlist_add_head_rcu(&policy->bydst, chain);
1557
1558 return delpol;
1559 }
1560
1561 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1562 {
1563 struct net *net = xp_net(policy);
1564 struct xfrm_policy *delpol;
1565 struct hlist_head *chain;
1566
1567 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1568 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1569 if (chain)
1570 delpol = xfrm_policy_insert_list(chain, policy, excl);
1571 else
1572 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1573
1574 if (IS_ERR(delpol)) {
1575 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1576 return PTR_ERR(delpol);
1577 }
1578
1579 __xfrm_policy_link(policy, dir);
1580
1581 /* After previous checking, family can either be AF_INET or AF_INET6 */
1582 if (policy->family == AF_INET)
1583 rt_genid_bump_ipv4(net);
1584 else
1585 rt_genid_bump_ipv6(net);
1586
1587 if (delpol) {
1588 xfrm_policy_requeue(delpol, policy);
1589 __xfrm_policy_unlink(delpol, dir);
1590 }
1591 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1592 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1593 policy->curlft.add_time = ktime_get_real_seconds();
1594 policy->curlft.use_time = 0;
1595 if (!mod_timer(&policy->timer, jiffies + HZ))
1596 xfrm_pol_hold(policy);
1597 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1598
1599 if (delpol)
1600 xfrm_policy_kill(delpol);
1601 else if (xfrm_bydst_should_resize(net, dir, NULL))
1602 schedule_work(&net->xfrm.policy_hash_work);
1603
1604 return 0;
1605 }
1606 EXPORT_SYMBOL(xfrm_policy_insert);
1607
1608 static struct xfrm_policy *
1609 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1610 u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1611 struct xfrm_sec_ctx *ctx)
1612 {
1613 struct xfrm_policy *pol;
1614
1615 if (!chain)
1616 return NULL;
1617
1618 hlist_for_each_entry(pol, chain, bydst) {
1619 if (pol->type == type &&
1620 pol->if_id == if_id &&
1621 xfrm_policy_mark_match(mark, pol) &&
1622 !selector_cmp(sel, &pol->selector) &&
1623 xfrm_sec_ctx_match(ctx, pol->security))
1624 return pol;
1625 }
1626
1627 return NULL;
1628 }
1629
1630 struct xfrm_policy *
1631 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1632 u8 type, int dir, struct xfrm_selector *sel,
1633 struct xfrm_sec_ctx *ctx, int delete, int *err)
1634 {
1635 struct xfrm_pol_inexact_bin *bin = NULL;
1636 struct xfrm_policy *pol, *ret = NULL;
1637 struct hlist_head *chain;
1638
1639 *err = 0;
1640 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1641 chain = policy_hash_bysel(net, sel, sel->family, dir);
1642 if (!chain) {
1643 struct xfrm_pol_inexact_candidates cand;
1644 int i;
1645
1646 bin = xfrm_policy_inexact_lookup(net, type,
1647 sel->family, dir, if_id);
1648 if (!bin) {
1649 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1650 return NULL;
1651 }
1652
1653 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1654 &sel->saddr,
1655 &sel->daddr)) {
1656 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1657 return NULL;
1658 }
1659
1660 pol = NULL;
1661 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1662 struct xfrm_policy *tmp;
1663
1664 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1665 if_id, type, dir,
1666 sel, ctx);
1667 if (!tmp)
1668 continue;
1669
1670 if (!pol || tmp->pos < pol->pos)
1671 pol = tmp;
1672 }
1673 } else {
1674 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1675 sel, ctx);
1676 }
1677
1678 if (pol) {
1679 xfrm_pol_hold(pol);
1680 if (delete) {
1681 *err = security_xfrm_policy_delete(pol->security);
1682 if (*err) {
1683 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1684 return pol;
1685 }
1686 __xfrm_policy_unlink(pol, dir);
1687 }
1688 ret = pol;
1689 }
1690 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1691
1692 if (ret && delete)
1693 xfrm_policy_kill(ret);
1694 if (bin && delete)
1695 xfrm_policy_inexact_prune_bin(bin);
1696 return ret;
1697 }
1698 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1699
1700 struct xfrm_policy *
1701 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1702 u8 type, int dir, u32 id, int delete, int *err)
1703 {
1704 struct xfrm_policy *pol, *ret;
1705 struct hlist_head *chain;
1706
1707 *err = -ENOENT;
1708 if (xfrm_policy_id2dir(id) != dir)
1709 return NULL;
1710
1711 *err = 0;
1712 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1713 chain = net->xfrm.policy_byidx + idx_hash(net, id);
1714 ret = NULL;
1715 hlist_for_each_entry(pol, chain, byidx) {
1716 if (pol->type == type && pol->index == id &&
1717 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1718 xfrm_pol_hold(pol);
1719 if (delete) {
1720 *err = security_xfrm_policy_delete(
1721 pol->security);
1722 if (*err) {
1723 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1724 return pol;
1725 }
1726 __xfrm_policy_unlink(pol, dir);
1727 }
1728 ret = pol;
1729 break;
1730 }
1731 }
1732 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1733
1734 if (ret && delete)
1735 xfrm_policy_kill(ret);
1736 return ret;
1737 }
1738 EXPORT_SYMBOL(xfrm_policy_byid);
1739
1740 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1741 static inline int
1742 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1743 {
1744 struct xfrm_policy *pol;
1745 int err = 0;
1746
1747 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1748 if (pol->walk.dead ||
1749 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1750 pol->type != type)
1751 continue;
1752
1753 err = security_xfrm_policy_delete(pol->security);
1754 if (err) {
1755 xfrm_audit_policy_delete(pol, 0, task_valid);
1756 return err;
1757 }
1758 }
1759 return err;
1760 }
1761 #else
1762 static inline int
1763 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1764 {
1765 return 0;
1766 }
1767 #endif
1768
1769 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1770 {
1771 int dir, err = 0, cnt = 0;
1772 struct xfrm_policy *pol;
1773
1774 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1775
1776 err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1777 if (err)
1778 goto out;
1779
1780 again:
1781 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1782 dir = xfrm_policy_id2dir(pol->index);
1783 if (pol->walk.dead ||
1784 dir >= XFRM_POLICY_MAX ||
1785 pol->type != type)
1786 continue;
1787
1788 __xfrm_policy_unlink(pol, dir);
1789 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1790 cnt++;
1791 xfrm_audit_policy_delete(pol, 1, task_valid);
1792 xfrm_policy_kill(pol);
1793 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1794 goto again;
1795 }
1796 if (cnt)
1797 __xfrm_policy_inexact_flush(net);
1798 else
1799 err = -ESRCH;
1800 out:
1801 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1802 return err;
1803 }
1804 EXPORT_SYMBOL(xfrm_policy_flush);
1805
1806 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1807 int (*func)(struct xfrm_policy *, int, int, void*),
1808 void *data)
1809 {
1810 struct xfrm_policy *pol;
1811 struct xfrm_policy_walk_entry *x;
1812 int error = 0;
1813
1814 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1815 walk->type != XFRM_POLICY_TYPE_ANY)
1816 return -EINVAL;
1817
1818 if (list_empty(&walk->walk.all) && walk->seq != 0)
1819 return 0;
1820
1821 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1822 if (list_empty(&walk->walk.all))
1823 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1824 else
1825 x = list_first_entry(&walk->walk.all,
1826 struct xfrm_policy_walk_entry, all);
1827
1828 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1829 if (x->dead)
1830 continue;
1831 pol = container_of(x, struct xfrm_policy, walk);
1832 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1833 walk->type != pol->type)
1834 continue;
1835 error = func(pol, xfrm_policy_id2dir(pol->index),
1836 walk->seq, data);
1837 if (error) {
1838 list_move_tail(&walk->walk.all, &x->all);
1839 goto out;
1840 }
1841 walk->seq++;
1842 }
1843 if (walk->seq == 0) {
1844 error = -ENOENT;
1845 goto out;
1846 }
1847 list_del_init(&walk->walk.all);
1848 out:
1849 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1850 return error;
1851 }
1852 EXPORT_SYMBOL(xfrm_policy_walk);
1853
1854 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1855 {
1856 INIT_LIST_HEAD(&walk->walk.all);
1857 walk->walk.dead = 1;
1858 walk->type = type;
1859 walk->seq = 0;
1860 }
1861 EXPORT_SYMBOL(xfrm_policy_walk_init);
1862
1863 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1864 {
1865 if (list_empty(&walk->walk.all))
1866 return;
1867
1868 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1869 list_del(&walk->walk.all);
1870 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1871 }
1872 EXPORT_SYMBOL(xfrm_policy_walk_done);
1873
1874 /*
1875 * Find policy to apply to this flow.
1876 *
1877 * Returns 0 if policy found, else an -errno.
1878 */
1879 static int xfrm_policy_match(const struct xfrm_policy *pol,
1880 const struct flowi *fl,
1881 u8 type, u16 family, int dir, u32 if_id)
1882 {
1883 const struct xfrm_selector *sel = &pol->selector;
1884 int ret = -ESRCH;
1885 bool match;
1886
1887 if (pol->family != family ||
1888 pol->if_id != if_id ||
1889 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1890 pol->type != type)
1891 return ret;
1892
1893 match = xfrm_selector_match(sel, fl, family);
1894 if (match)
1895 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1896 dir);
1897 return ret;
1898 }
1899
1900 static struct xfrm_pol_inexact_node *
1901 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1902 seqcount_spinlock_t *count,
1903 const xfrm_address_t *addr, u16 family)
1904 {
1905 const struct rb_node *parent;
1906 int seq;
1907
1908 again:
1909 seq = read_seqcount_begin(count);
1910
1911 parent = rcu_dereference_raw(r->rb_node);
1912 while (parent) {
1913 struct xfrm_pol_inexact_node *node;
1914 int delta;
1915
1916 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
1917
1918 delta = xfrm_policy_addr_delta(addr, &node->addr,
1919 node->prefixlen, family);
1920 if (delta < 0) {
1921 parent = rcu_dereference_raw(parent->rb_left);
1922 continue;
1923 } else if (delta > 0) {
1924 parent = rcu_dereference_raw(parent->rb_right);
1925 continue;
1926 }
1927
1928 return node;
1929 }
1930
1931 if (read_seqcount_retry(count, seq))
1932 goto again;
1933
1934 return NULL;
1935 }
1936
1937 static bool
1938 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
1939 struct xfrm_pol_inexact_bin *b,
1940 const xfrm_address_t *saddr,
1941 const xfrm_address_t *daddr)
1942 {
1943 struct xfrm_pol_inexact_node *n;
1944 u16 family;
1945
1946 if (!b)
1947 return false;
1948
1949 family = b->k.family;
1950 memset(cand, 0, sizeof(*cand));
1951 cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
1952
1953 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
1954 family);
1955 if (n) {
1956 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
1957 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
1958 family);
1959 if (n)
1960 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
1961 }
1962
1963 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
1964 family);
1965 if (n)
1966 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
1967
1968 return true;
1969 }
1970
1971 static struct xfrm_pol_inexact_bin *
1972 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
1973 u8 dir, u32 if_id)
1974 {
1975 struct xfrm_pol_inexact_key k = {
1976 .family = family,
1977 .type = type,
1978 .dir = dir,
1979 .if_id = if_id,
1980 };
1981
1982 write_pnet(&k.net, net);
1983
1984 return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
1985 xfrm_pol_inexact_params);
1986 }
1987
1988 static struct xfrm_pol_inexact_bin *
1989 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
1990 u8 dir, u32 if_id)
1991 {
1992 struct xfrm_pol_inexact_bin *bin;
1993
1994 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1995
1996 rcu_read_lock();
1997 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
1998 rcu_read_unlock();
1999
2000 return bin;
2001 }
2002
2003 static struct xfrm_policy *
2004 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2005 struct xfrm_policy *prefer,
2006 const struct flowi *fl,
2007 u8 type, u16 family, int dir, u32 if_id)
2008 {
2009 u32 priority = prefer ? prefer->priority : ~0u;
2010 struct xfrm_policy *pol;
2011
2012 if (!chain)
2013 return NULL;
2014
2015 hlist_for_each_entry_rcu(pol, chain, bydst) {
2016 int err;
2017
2018 if (pol->priority > priority)
2019 break;
2020
2021 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2022 if (err) {
2023 if (err != -ESRCH)
2024 return ERR_PTR(err);
2025
2026 continue;
2027 }
2028
2029 if (prefer) {
2030 /* matches. Is it older than *prefer? */
2031 if (pol->priority == priority &&
2032 prefer->pos < pol->pos)
2033 return prefer;
2034 }
2035
2036 return pol;
2037 }
2038
2039 return NULL;
2040 }
2041
2042 static struct xfrm_policy *
2043 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2044 struct xfrm_policy *prefer,
2045 const struct flowi *fl,
2046 u8 type, u16 family, int dir, u32 if_id)
2047 {
2048 struct xfrm_policy *tmp;
2049 int i;
2050
2051 for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2052 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2053 prefer,
2054 fl, type, family, dir,
2055 if_id);
2056 if (!tmp)
2057 continue;
2058
2059 if (IS_ERR(tmp))
2060 return tmp;
2061 prefer = tmp;
2062 }
2063
2064 return prefer;
2065 }
2066
2067 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2068 const struct flowi *fl,
2069 u16 family, u8 dir,
2070 u32 if_id)
2071 {
2072 struct xfrm_pol_inexact_candidates cand;
2073 const xfrm_address_t *daddr, *saddr;
2074 struct xfrm_pol_inexact_bin *bin;
2075 struct xfrm_policy *pol, *ret;
2076 struct hlist_head *chain;
2077 unsigned int sequence;
2078 int err;
2079
2080 daddr = xfrm_flowi_daddr(fl, family);
2081 saddr = xfrm_flowi_saddr(fl, family);
2082 if (unlikely(!daddr || !saddr))
2083 return NULL;
2084
2085 rcu_read_lock();
2086 retry:
2087 do {
2088 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
2089 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2090 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
2091
2092 ret = NULL;
2093 hlist_for_each_entry_rcu(pol, chain, bydst) {
2094 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2095 if (err) {
2096 if (err == -ESRCH)
2097 continue;
2098 else {
2099 ret = ERR_PTR(err);
2100 goto fail;
2101 }
2102 } else {
2103 ret = pol;
2104 break;
2105 }
2106 }
2107 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2108 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2109 daddr))
2110 goto skip_inexact;
2111
2112 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2113 family, dir, if_id);
2114 if (pol) {
2115 ret = pol;
2116 if (IS_ERR(pol))
2117 goto fail;
2118 }
2119
2120 skip_inexact:
2121 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
2122 goto retry;
2123
2124 if (ret && !xfrm_pol_hold_rcu(ret))
2125 goto retry;
2126 fail:
2127 rcu_read_unlock();
2128
2129 return ret;
2130 }
2131
2132 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2133 const struct flowi *fl,
2134 u16 family, u8 dir, u32 if_id)
2135 {
2136 #ifdef CONFIG_XFRM_SUB_POLICY
2137 struct xfrm_policy *pol;
2138
2139 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2140 dir, if_id);
2141 if (pol != NULL)
2142 return pol;
2143 #endif
2144 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2145 dir, if_id);
2146 }
2147
2148 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2149 const struct flowi *fl,
2150 u16 family, u32 if_id)
2151 {
2152 struct xfrm_policy *pol;
2153
2154 rcu_read_lock();
2155 again:
2156 pol = rcu_dereference(sk->sk_policy[dir]);
2157 if (pol != NULL) {
2158 bool match;
2159 int err = 0;
2160
2161 if (pol->family != family) {
2162 pol = NULL;
2163 goto out;
2164 }
2165
2166 match = xfrm_selector_match(&pol->selector, fl, family);
2167 if (match) {
2168 if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
2169 pol->if_id != if_id) {
2170 pol = NULL;
2171 goto out;
2172 }
2173 err = security_xfrm_policy_lookup(pol->security,
2174 fl->flowi_secid,
2175 dir);
2176 if (!err) {
2177 if (!xfrm_pol_hold_rcu(pol))
2178 goto again;
2179 } else if (err == -ESRCH) {
2180 pol = NULL;
2181 } else {
2182 pol = ERR_PTR(err);
2183 }
2184 } else
2185 pol = NULL;
2186 }
2187 out:
2188 rcu_read_unlock();
2189 return pol;
2190 }
2191
2192 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2193 {
2194 struct net *net = xp_net(pol);
2195
2196 list_add(&pol->walk.all, &net->xfrm.policy_all);
2197 net->xfrm.policy_count[dir]++;
2198 xfrm_pol_hold(pol);
2199 }
2200
2201 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2202 int dir)
2203 {
2204 struct net *net = xp_net(pol);
2205
2206 if (list_empty(&pol->walk.all))
2207 return NULL;
2208
2209 /* Socket policies are not hashed. */
2210 if (!hlist_unhashed(&pol->bydst)) {
2211 hlist_del_rcu(&pol->bydst);
2212 hlist_del_init(&pol->bydst_inexact_list);
2213 hlist_del(&pol->byidx);
2214 }
2215
2216 list_del_init(&pol->walk.all);
2217 net->xfrm.policy_count[dir]--;
2218
2219 return pol;
2220 }
2221
2222 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2223 {
2224 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2225 }
2226
2227 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2228 {
2229 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2230 }
2231
2232 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2233 {
2234 struct net *net = xp_net(pol);
2235
2236 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2237 pol = __xfrm_policy_unlink(pol, dir);
2238 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2239 if (pol) {
2240 xfrm_policy_kill(pol);
2241 return 0;
2242 }
2243 return -ENOENT;
2244 }
2245 EXPORT_SYMBOL(xfrm_policy_delete);
2246
2247 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2248 {
2249 struct net *net = sock_net(sk);
2250 struct xfrm_policy *old_pol;
2251
2252 #ifdef CONFIG_XFRM_SUB_POLICY
2253 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2254 return -EINVAL;
2255 #endif
2256
2257 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2258 old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2259 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2260 if (pol) {
2261 pol->curlft.add_time = ktime_get_real_seconds();
2262 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2263 xfrm_sk_policy_link(pol, dir);
2264 }
2265 rcu_assign_pointer(sk->sk_policy[dir], pol);
2266 if (old_pol) {
2267 if (pol)
2268 xfrm_policy_requeue(old_pol, pol);
2269
2270 /* Unlinking succeeds always. This is the only function
2271 * allowed to delete or replace socket policy.
2272 */
2273 xfrm_sk_policy_unlink(old_pol, dir);
2274 }
2275 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2276
2277 if (old_pol) {
2278 xfrm_policy_kill(old_pol);
2279 }
2280 return 0;
2281 }
2282
2283 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2284 {
2285 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2286 struct net *net = xp_net(old);
2287
2288 if (newp) {
2289 newp->selector = old->selector;
2290 if (security_xfrm_policy_clone(old->security,
2291 &newp->security)) {
2292 kfree(newp);
2293 return NULL; /* ENOMEM */
2294 }
2295 newp->lft = old->lft;
2296 newp->curlft = old->curlft;
2297 newp->mark = old->mark;
2298 newp->if_id = old->if_id;
2299 newp->action = old->action;
2300 newp->flags = old->flags;
2301 newp->xfrm_nr = old->xfrm_nr;
2302 newp->index = old->index;
2303 newp->type = old->type;
2304 newp->family = old->family;
2305 memcpy(newp->xfrm_vec, old->xfrm_vec,
2306 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2307 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2308 xfrm_sk_policy_link(newp, dir);
2309 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2310 xfrm_pol_put(newp);
2311 }
2312 return newp;
2313 }
2314
2315 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2316 {
2317 const struct xfrm_policy *p;
2318 struct xfrm_policy *np;
2319 int i, ret = 0;
2320
2321 rcu_read_lock();
2322 for (i = 0; i < 2; i++) {
2323 p = rcu_dereference(osk->sk_policy[i]);
2324 if (p) {
2325 np = clone_policy(p, i);
2326 if (unlikely(!np)) {
2327 ret = -ENOMEM;
2328 break;
2329 }
2330 rcu_assign_pointer(sk->sk_policy[i], np);
2331 }
2332 }
2333 rcu_read_unlock();
2334 return ret;
2335 }
2336
2337 static int
2338 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2339 xfrm_address_t *remote, unsigned short family, u32 mark)
2340 {
2341 int err;
2342 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2343
2344 if (unlikely(afinfo == NULL))
2345 return -EINVAL;
2346 err = afinfo->get_saddr(net, oif, local, remote, mark);
2347 rcu_read_unlock();
2348 return err;
2349 }
2350
2351 /* Resolve list of templates for the flow, given policy. */
2352
2353 static int
2354 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2355 struct xfrm_state **xfrm, unsigned short family)
2356 {
2357 struct net *net = xp_net(policy);
2358 int nx;
2359 int i, error;
2360 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2361 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2362 xfrm_address_t tmp;
2363
2364 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2365 struct xfrm_state *x;
2366 xfrm_address_t *remote = daddr;
2367 xfrm_address_t *local = saddr;
2368 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2369
2370 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2371 tmpl->mode == XFRM_MODE_BEET) {
2372 remote = &tmpl->id.daddr;
2373 local = &tmpl->saddr;
2374 if (xfrm_addr_any(local, tmpl->encap_family)) {
2375 error = xfrm_get_saddr(net, fl->flowi_oif,
2376 &tmp, remote,
2377 tmpl->encap_family, 0);
2378 if (error)
2379 goto fail;
2380 local = &tmp;
2381 }
2382 }
2383
2384 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2385 family, policy->if_id);
2386
2387 if (x && x->km.state == XFRM_STATE_VALID) {
2388 xfrm[nx++] = x;
2389 daddr = remote;
2390 saddr = local;
2391 continue;
2392 }
2393 if (x) {
2394 error = (x->km.state == XFRM_STATE_ERROR ?
2395 -EINVAL : -EAGAIN);
2396 xfrm_state_put(x);
2397 } else if (error == -ESRCH) {
2398 error = -EAGAIN;
2399 }
2400
2401 if (!tmpl->optional)
2402 goto fail;
2403 }
2404 return nx;
2405
2406 fail:
2407 for (nx--; nx >= 0; nx--)
2408 xfrm_state_put(xfrm[nx]);
2409 return error;
2410 }
2411
2412 static int
2413 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2414 struct xfrm_state **xfrm, unsigned short family)
2415 {
2416 struct xfrm_state *tp[XFRM_MAX_DEPTH];
2417 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2418 int cnx = 0;
2419 int error;
2420 int ret;
2421 int i;
2422
2423 for (i = 0; i < npols; i++) {
2424 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2425 error = -ENOBUFS;
2426 goto fail;
2427 }
2428
2429 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2430 if (ret < 0) {
2431 error = ret;
2432 goto fail;
2433 } else
2434 cnx += ret;
2435 }
2436
2437 /* found states are sorted for outbound processing */
2438 if (npols > 1)
2439 xfrm_state_sort(xfrm, tpp, cnx, family);
2440
2441 return cnx;
2442
2443 fail:
2444 for (cnx--; cnx >= 0; cnx--)
2445 xfrm_state_put(tpp[cnx]);
2446 return error;
2447
2448 }
2449
2450 static int xfrm_get_tos(const struct flowi *fl, int family)
2451 {
2452 if (family == AF_INET)
2453 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2454
2455 return 0;
2456 }
2457
2458 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2459 {
2460 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2461 struct dst_ops *dst_ops;
2462 struct xfrm_dst *xdst;
2463
2464 if (!afinfo)
2465 return ERR_PTR(-EINVAL);
2466
2467 switch (family) {
2468 case AF_INET:
2469 dst_ops = &net->xfrm.xfrm4_dst_ops;
2470 break;
2471 #if IS_ENABLED(CONFIG_IPV6)
2472 case AF_INET6:
2473 dst_ops = &net->xfrm.xfrm6_dst_ops;
2474 break;
2475 #endif
2476 default:
2477 BUG();
2478 }
2479 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2480
2481 if (likely(xdst)) {
2482 struct dst_entry *dst = &xdst->u.dst;
2483
2484 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
2485 } else
2486 xdst = ERR_PTR(-ENOBUFS);
2487
2488 rcu_read_unlock();
2489
2490 return xdst;
2491 }
2492
2493 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2494 int nfheader_len)
2495 {
2496 if (dst->ops->family == AF_INET6) {
2497 struct rt6_info *rt = (struct rt6_info *)dst;
2498 path->path_cookie = rt6_get_cookie(rt);
2499 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2500 }
2501 }
2502
2503 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2504 const struct flowi *fl)
2505 {
2506 const struct xfrm_policy_afinfo *afinfo =
2507 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2508 int err;
2509
2510 if (!afinfo)
2511 return -EINVAL;
2512
2513 err = afinfo->fill_dst(xdst, dev, fl);
2514
2515 rcu_read_unlock();
2516
2517 return err;
2518 }
2519
2520
2521 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2522 * all the metrics... Shortly, bundle a bundle.
2523 */
2524
2525 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2526 struct xfrm_state **xfrm,
2527 struct xfrm_dst **bundle,
2528 int nx,
2529 const struct flowi *fl,
2530 struct dst_entry *dst)
2531 {
2532 const struct xfrm_state_afinfo *afinfo;
2533 const struct xfrm_mode *inner_mode;
2534 struct net *net = xp_net(policy);
2535 unsigned long now = jiffies;
2536 struct net_device *dev;
2537 struct xfrm_dst *xdst_prev = NULL;
2538 struct xfrm_dst *xdst0 = NULL;
2539 int i = 0;
2540 int err;
2541 int header_len = 0;
2542 int nfheader_len = 0;
2543 int trailer_len = 0;
2544 int tos;
2545 int family = policy->selector.family;
2546 xfrm_address_t saddr, daddr;
2547
2548 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2549
2550 tos = xfrm_get_tos(fl, family);
2551
2552 dst_hold(dst);
2553
2554 for (; i < nx; i++) {
2555 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2556 struct dst_entry *dst1 = &xdst->u.dst;
2557
2558 err = PTR_ERR(xdst);
2559 if (IS_ERR(xdst)) {
2560 dst_release(dst);
2561 goto put_states;
2562 }
2563
2564 bundle[i] = xdst;
2565 if (!xdst_prev)
2566 xdst0 = xdst;
2567 else
2568 /* Ref count is taken during xfrm_alloc_dst()
2569 * No need to do dst_clone() on dst1
2570 */
2571 xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2572
2573 if (xfrm[i]->sel.family == AF_UNSPEC) {
2574 inner_mode = xfrm_ip2inner_mode(xfrm[i],
2575 xfrm_af2proto(family));
2576 if (!inner_mode) {
2577 err = -EAFNOSUPPORT;
2578 dst_release(dst);
2579 goto put_states;
2580 }
2581 } else
2582 inner_mode = &xfrm[i]->inner_mode;
2583
2584 xdst->route = dst;
2585 dst_copy_metrics(dst1, dst);
2586
2587 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2588 __u32 mark = 0;
2589
2590 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2591 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2592
2593 family = xfrm[i]->props.family;
2594 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
2595 &saddr, &daddr, family, mark);
2596 err = PTR_ERR(dst);
2597 if (IS_ERR(dst))
2598 goto put_states;
2599 } else
2600 dst_hold(dst);
2601
2602 dst1->xfrm = xfrm[i];
2603 xdst->xfrm_genid = xfrm[i]->genid;
2604
2605 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2606 dst1->lastuse = now;
2607
2608 dst1->input = dst_discard;
2609
2610 rcu_read_lock();
2611 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2612 if (likely(afinfo))
2613 dst1->output = afinfo->output;
2614 else
2615 dst1->output = dst_discard_out;
2616 rcu_read_unlock();
2617
2618 xdst_prev = xdst;
2619
2620 header_len += xfrm[i]->props.header_len;
2621 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2622 nfheader_len += xfrm[i]->props.header_len;
2623 trailer_len += xfrm[i]->props.trailer_len;
2624 }
2625
2626 xfrm_dst_set_child(xdst_prev, dst);
2627 xdst0->path = dst;
2628
2629 err = -ENODEV;
2630 dev = dst->dev;
2631 if (!dev)
2632 goto free_dst;
2633
2634 xfrm_init_path(xdst0, dst, nfheader_len);
2635 xfrm_init_pmtu(bundle, nx);
2636
2637 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2638 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2639 err = xfrm_fill_dst(xdst_prev, dev, fl);
2640 if (err)
2641 goto free_dst;
2642
2643 xdst_prev->u.dst.header_len = header_len;
2644 xdst_prev->u.dst.trailer_len = trailer_len;
2645 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2646 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2647 }
2648
2649 return &xdst0->u.dst;
2650
2651 put_states:
2652 for (; i < nx; i++)
2653 xfrm_state_put(xfrm[i]);
2654 free_dst:
2655 if (xdst0)
2656 dst_release_immediate(&xdst0->u.dst);
2657
2658 return ERR_PTR(err);
2659 }
2660
2661 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2662 struct xfrm_policy **pols,
2663 int *num_pols, int *num_xfrms)
2664 {
2665 int i;
2666
2667 if (*num_pols == 0 || !pols[0]) {
2668 *num_pols = 0;
2669 *num_xfrms = 0;
2670 return 0;
2671 }
2672 if (IS_ERR(pols[0]))
2673 return PTR_ERR(pols[0]);
2674
2675 *num_xfrms = pols[0]->xfrm_nr;
2676
2677 #ifdef CONFIG_XFRM_SUB_POLICY
2678 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
2679 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2680 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2681 XFRM_POLICY_TYPE_MAIN,
2682 fl, family,
2683 XFRM_POLICY_OUT,
2684 pols[0]->if_id);
2685 if (pols[1]) {
2686 if (IS_ERR(pols[1])) {
2687 xfrm_pols_put(pols, *num_pols);
2688 return PTR_ERR(pols[1]);
2689 }
2690 (*num_pols)++;
2691 (*num_xfrms) += pols[1]->xfrm_nr;
2692 }
2693 }
2694 #endif
2695 for (i = 0; i < *num_pols; i++) {
2696 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2697 *num_xfrms = -1;
2698 break;
2699 }
2700 }
2701
2702 return 0;
2703
2704 }
2705
2706 static struct xfrm_dst *
2707 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2708 const struct flowi *fl, u16 family,
2709 struct dst_entry *dst_orig)
2710 {
2711 struct net *net = xp_net(pols[0]);
2712 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2713 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2714 struct xfrm_dst *xdst;
2715 struct dst_entry *dst;
2716 int err;
2717
2718 /* Try to instantiate a bundle */
2719 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2720 if (err <= 0) {
2721 if (err == 0)
2722 return NULL;
2723
2724 if (err != -EAGAIN)
2725 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2726 return ERR_PTR(err);
2727 }
2728
2729 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2730 if (IS_ERR(dst)) {
2731 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2732 return ERR_CAST(dst);
2733 }
2734
2735 xdst = (struct xfrm_dst *)dst;
2736 xdst->num_xfrms = err;
2737 xdst->num_pols = num_pols;
2738 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2739 xdst->policy_genid = atomic_read(&pols[0]->genid);
2740
2741 return xdst;
2742 }
2743
2744 static void xfrm_policy_queue_process(struct timer_list *t)
2745 {
2746 struct sk_buff *skb;
2747 struct sock *sk;
2748 struct dst_entry *dst;
2749 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2750 struct net *net = xp_net(pol);
2751 struct xfrm_policy_queue *pq = &pol->polq;
2752 struct flowi fl;
2753 struct sk_buff_head list;
2754 __u32 skb_mark;
2755
2756 spin_lock(&pq->hold_queue.lock);
2757 skb = skb_peek(&pq->hold_queue);
2758 if (!skb) {
2759 spin_unlock(&pq->hold_queue.lock);
2760 goto out;
2761 }
2762 dst = skb_dst(skb);
2763 sk = skb->sk;
2764
2765 /* Fixup the mark to support VTI. */
2766 skb_mark = skb->mark;
2767 skb->mark = pol->mark.v;
2768 xfrm_decode_session(skb, &fl, dst->ops->family);
2769 skb->mark = skb_mark;
2770 spin_unlock(&pq->hold_queue.lock);
2771
2772 dst_hold(xfrm_dst_path(dst));
2773 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2774 if (IS_ERR(dst))
2775 goto purge_queue;
2776
2777 if (dst->flags & DST_XFRM_QUEUE) {
2778 dst_release(dst);
2779
2780 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2781 goto purge_queue;
2782
2783 pq->timeout = pq->timeout << 1;
2784 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2785 xfrm_pol_hold(pol);
2786 goto out;
2787 }
2788
2789 dst_release(dst);
2790
2791 __skb_queue_head_init(&list);
2792
2793 spin_lock(&pq->hold_queue.lock);
2794 pq->timeout = 0;
2795 skb_queue_splice_init(&pq->hold_queue, &list);
2796 spin_unlock(&pq->hold_queue.lock);
2797
2798 while (!skb_queue_empty(&list)) {
2799 skb = __skb_dequeue(&list);
2800
2801 /* Fixup the mark to support VTI. */
2802 skb_mark = skb->mark;
2803 skb->mark = pol->mark.v;
2804 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2805 skb->mark = skb_mark;
2806
2807 dst_hold(xfrm_dst_path(skb_dst(skb)));
2808 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2809 if (IS_ERR(dst)) {
2810 kfree_skb(skb);
2811 continue;
2812 }
2813
2814 nf_reset_ct(skb);
2815 skb_dst_drop(skb);
2816 skb_dst_set(skb, dst);
2817
2818 dst_output(net, skb->sk, skb);
2819 }
2820
2821 out:
2822 xfrm_pol_put(pol);
2823 return;
2824
2825 purge_queue:
2826 pq->timeout = 0;
2827 skb_queue_purge(&pq->hold_queue);
2828 xfrm_pol_put(pol);
2829 }
2830
2831 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2832 {
2833 unsigned long sched_next;
2834 struct dst_entry *dst = skb_dst(skb);
2835 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2836 struct xfrm_policy *pol = xdst->pols[0];
2837 struct xfrm_policy_queue *pq = &pol->polq;
2838
2839 if (unlikely(skb_fclone_busy(sk, skb))) {
2840 kfree_skb(skb);
2841 return 0;
2842 }
2843
2844 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2845 kfree_skb(skb);
2846 return -EAGAIN;
2847 }
2848
2849 skb_dst_force(skb);
2850
2851 spin_lock_bh(&pq->hold_queue.lock);
2852
2853 if (!pq->timeout)
2854 pq->timeout = XFRM_QUEUE_TMO_MIN;
2855
2856 sched_next = jiffies + pq->timeout;
2857
2858 if (del_timer(&pq->hold_timer)) {
2859 if (time_before(pq->hold_timer.expires, sched_next))
2860 sched_next = pq->hold_timer.expires;
2861 xfrm_pol_put(pol);
2862 }
2863
2864 __skb_queue_tail(&pq->hold_queue, skb);
2865 if (!mod_timer(&pq->hold_timer, sched_next))
2866 xfrm_pol_hold(pol);
2867
2868 spin_unlock_bh(&pq->hold_queue.lock);
2869
2870 return 0;
2871 }
2872
2873 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2874 struct xfrm_flo *xflo,
2875 const struct flowi *fl,
2876 int num_xfrms,
2877 u16 family)
2878 {
2879 int err;
2880 struct net_device *dev;
2881 struct dst_entry *dst;
2882 struct dst_entry *dst1;
2883 struct xfrm_dst *xdst;
2884
2885 xdst = xfrm_alloc_dst(net, family);
2886 if (IS_ERR(xdst))
2887 return xdst;
2888
2889 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2890 net->xfrm.sysctl_larval_drop ||
2891 num_xfrms <= 0)
2892 return xdst;
2893
2894 dst = xflo->dst_orig;
2895 dst1 = &xdst->u.dst;
2896 dst_hold(dst);
2897 xdst->route = dst;
2898
2899 dst_copy_metrics(dst1, dst);
2900
2901 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2902 dst1->flags |= DST_XFRM_QUEUE;
2903 dst1->lastuse = jiffies;
2904
2905 dst1->input = dst_discard;
2906 dst1->output = xdst_queue_output;
2907
2908 dst_hold(dst);
2909 xfrm_dst_set_child(xdst, dst);
2910 xdst->path = dst;
2911
2912 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2913
2914 err = -ENODEV;
2915 dev = dst->dev;
2916 if (!dev)
2917 goto free_dst;
2918
2919 err = xfrm_fill_dst(xdst, dev, fl);
2920 if (err)
2921 goto free_dst;
2922
2923 out:
2924 return xdst;
2925
2926 free_dst:
2927 dst_release(dst1);
2928 xdst = ERR_PTR(err);
2929 goto out;
2930 }
2931
2932 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
2933 const struct flowi *fl,
2934 u16 family, u8 dir,
2935 struct xfrm_flo *xflo, u32 if_id)
2936 {
2937 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2938 int num_pols = 0, num_xfrms = 0, err;
2939 struct xfrm_dst *xdst;
2940
2941 /* Resolve policies to use if we couldn't get them from
2942 * previous cache entry */
2943 num_pols = 1;
2944 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
2945 err = xfrm_expand_policies(fl, family, pols,
2946 &num_pols, &num_xfrms);
2947 if (err < 0)
2948 goto inc_error;
2949 if (num_pols == 0)
2950 return NULL;
2951 if (num_xfrms <= 0)
2952 goto make_dummy_bundle;
2953
2954 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2955 xflo->dst_orig);
2956 if (IS_ERR(xdst)) {
2957 err = PTR_ERR(xdst);
2958 if (err == -EREMOTE) {
2959 xfrm_pols_put(pols, num_pols);
2960 return NULL;
2961 }
2962
2963 if (err != -EAGAIN)
2964 goto error;
2965 goto make_dummy_bundle;
2966 } else if (xdst == NULL) {
2967 num_xfrms = 0;
2968 goto make_dummy_bundle;
2969 }
2970
2971 return xdst;
2972
2973 make_dummy_bundle:
2974 /* We found policies, but there's no bundles to instantiate:
2975 * either because the policy blocks, has no transformations or
2976 * we could not build template (no xfrm_states).*/
2977 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2978 if (IS_ERR(xdst)) {
2979 xfrm_pols_put(pols, num_pols);
2980 return ERR_CAST(xdst);
2981 }
2982 xdst->num_pols = num_pols;
2983 xdst->num_xfrms = num_xfrms;
2984 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2985
2986 return xdst;
2987
2988 inc_error:
2989 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2990 error:
2991 xfrm_pols_put(pols, num_pols);
2992 return ERR_PTR(err);
2993 }
2994
2995 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2996 struct dst_entry *dst_orig)
2997 {
2998 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2999 struct dst_entry *ret;
3000
3001 if (!afinfo) {
3002 dst_release(dst_orig);
3003 return ERR_PTR(-EINVAL);
3004 } else {
3005 ret = afinfo->blackhole_route(net, dst_orig);
3006 }
3007 rcu_read_unlock();
3008
3009 return ret;
3010 }
3011
3012 /* Finds/creates a bundle for given flow and if_id
3013 *
3014 * At the moment we eat a raw IP route. Mostly to speed up lookups
3015 * on interfaces with disabled IPsec.
3016 *
3017 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3018 * compatibility
3019 */
3020 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3021 struct dst_entry *dst_orig,
3022 const struct flowi *fl,
3023 const struct sock *sk,
3024 int flags, u32 if_id)
3025 {
3026 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3027 struct xfrm_dst *xdst;
3028 struct dst_entry *dst, *route;
3029 u16 family = dst_orig->ops->family;
3030 u8 dir = XFRM_POLICY_OUT;
3031 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3032
3033 dst = NULL;
3034 xdst = NULL;
3035 route = NULL;
3036
3037 sk = sk_const_to_full_sk(sk);
3038 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3039 num_pols = 1;
3040 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3041 if_id);
3042 err = xfrm_expand_policies(fl, family, pols,
3043 &num_pols, &num_xfrms);
3044 if (err < 0)
3045 goto dropdst;
3046
3047 if (num_pols) {
3048 if (num_xfrms <= 0) {
3049 drop_pols = num_pols;
3050 goto no_transform;
3051 }
3052
3053 xdst = xfrm_resolve_and_create_bundle(
3054 pols, num_pols, fl,
3055 family, dst_orig);
3056
3057 if (IS_ERR(xdst)) {
3058 xfrm_pols_put(pols, num_pols);
3059 err = PTR_ERR(xdst);
3060 if (err == -EREMOTE)
3061 goto nopol;
3062
3063 goto dropdst;
3064 } else if (xdst == NULL) {
3065 num_xfrms = 0;
3066 drop_pols = num_pols;
3067 goto no_transform;
3068 }
3069
3070 route = xdst->route;
3071 }
3072 }
3073
3074 if (xdst == NULL) {
3075 struct xfrm_flo xflo;
3076
3077 xflo.dst_orig = dst_orig;
3078 xflo.flags = flags;
3079
3080 /* To accelerate a bit... */
3081 if ((dst_orig->flags & DST_NOXFRM) ||
3082 !net->xfrm.policy_count[XFRM_POLICY_OUT])
3083 goto nopol;
3084
3085 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3086 if (xdst == NULL)
3087 goto nopol;
3088 if (IS_ERR(xdst)) {
3089 err = PTR_ERR(xdst);
3090 goto dropdst;
3091 }
3092
3093 num_pols = xdst->num_pols;
3094 num_xfrms = xdst->num_xfrms;
3095 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3096 route = xdst->route;
3097 }
3098
3099 dst = &xdst->u.dst;
3100 if (route == NULL && num_xfrms > 0) {
3101 /* The only case when xfrm_bundle_lookup() returns a
3102 * bundle with null route, is when the template could
3103 * not be resolved. It means policies are there, but
3104 * bundle could not be created, since we don't yet
3105 * have the xfrm_state's. We need to wait for KM to
3106 * negotiate new SA's or bail out with error.*/
3107 if (net->xfrm.sysctl_larval_drop) {
3108 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3109 err = -EREMOTE;
3110 goto error;
3111 }
3112
3113 err = -EAGAIN;
3114
3115 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3116 goto error;
3117 }
3118
3119 no_transform:
3120 if (num_pols == 0)
3121 goto nopol;
3122
3123 if ((flags & XFRM_LOOKUP_ICMP) &&
3124 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3125 err = -ENOENT;
3126 goto error;
3127 }
3128
3129 for (i = 0; i < num_pols; i++)
3130 pols[i]->curlft.use_time = ktime_get_real_seconds();
3131
3132 if (num_xfrms < 0) {
3133 /* Prohibit the flow */
3134 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3135 err = -EPERM;
3136 goto error;
3137 } else if (num_xfrms > 0) {
3138 /* Flow transformed */
3139 dst_release(dst_orig);
3140 } else {
3141 /* Flow passes untransformed */
3142 dst_release(dst);
3143 dst = dst_orig;
3144 }
3145 ok:
3146 xfrm_pols_put(pols, drop_pols);
3147 if (dst && dst->xfrm &&
3148 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3149 dst->flags |= DST_XFRM_TUNNEL;
3150 return dst;
3151
3152 nopol:
3153 if (!(flags & XFRM_LOOKUP_ICMP)) {
3154 dst = dst_orig;
3155 goto ok;
3156 }
3157 err = -ENOENT;
3158 error:
3159 dst_release(dst);
3160 dropdst:
3161 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3162 dst_release(dst_orig);
3163 xfrm_pols_put(pols, drop_pols);
3164 return ERR_PTR(err);
3165 }
3166 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3167
3168 /* Main function: finds/creates a bundle for given flow.
3169 *
3170 * At the moment we eat a raw IP route. Mostly to speed up lookups
3171 * on interfaces with disabled IPsec.
3172 */
3173 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3174 const struct flowi *fl, const struct sock *sk,
3175 int flags)
3176 {
3177 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3178 }
3179 EXPORT_SYMBOL(xfrm_lookup);
3180
3181 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3182 * Otherwise we may send out blackholed packets.
3183 */
3184 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3185 const struct flowi *fl,
3186 const struct sock *sk, int flags)
3187 {
3188 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3189 flags | XFRM_LOOKUP_QUEUE |
3190 XFRM_LOOKUP_KEEP_DST_REF);
3191
3192 if (PTR_ERR(dst) == -EREMOTE)
3193 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3194
3195 if (IS_ERR(dst))
3196 dst_release(dst_orig);
3197
3198 return dst;
3199 }
3200 EXPORT_SYMBOL(xfrm_lookup_route);
3201
3202 static inline int
3203 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3204 {
3205 struct sec_path *sp = skb_sec_path(skb);
3206 struct xfrm_state *x;
3207
3208 if (!sp || idx < 0 || idx >= sp->len)
3209 return 0;
3210 x = sp->xvec[idx];
3211 if (!x->type->reject)
3212 return 0;
3213 return x->type->reject(x, skb, fl);
3214 }
3215
3216 /* When skb is transformed back to its "native" form, we have to
3217 * check policy restrictions. At the moment we make this in maximally
3218 * stupid way. Shame on me. :-) Of course, connected sockets must
3219 * have policy cached at them.
3220 */
3221
3222 static inline int
3223 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3224 unsigned short family)
3225 {
3226 if (xfrm_state_kern(x))
3227 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3228 return x->id.proto == tmpl->id.proto &&
3229 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3230 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3231 x->props.mode == tmpl->mode &&
3232 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3233 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3234 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3235 xfrm_state_addr_cmp(tmpl, x, family));
3236 }
3237
3238 /*
3239 * 0 or more than 0 is returned when validation is succeeded (either bypass
3240 * because of optional transport mode, or next index of the mathced secpath
3241 * state with the template.
3242 * -1 is returned when no matching template is found.
3243 * Otherwise "-2 - errored_index" is returned.
3244 */
3245 static inline int
3246 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3247 unsigned short family)
3248 {
3249 int idx = start;
3250
3251 if (tmpl->optional) {
3252 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3253 return start;
3254 } else
3255 start = -1;
3256 for (; idx < sp->len; idx++) {
3257 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
3258 return ++idx;
3259 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3260 if (start == -1)
3261 start = -2-idx;
3262 break;
3263 }
3264 }
3265 return start;
3266 }
3267
3268 static void
3269 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3270 {
3271 const struct iphdr *iph = ip_hdr(skb);
3272 int ihl = iph->ihl;
3273 u8 *xprth = skb_network_header(skb) + ihl * 4;
3274 struct flowi4 *fl4 = &fl->u.ip4;
3275 int oif = 0;
3276
3277 if (skb_dst(skb) && skb_dst(skb)->dev)
3278 oif = skb_dst(skb)->dev->ifindex;
3279
3280 memset(fl4, 0, sizeof(struct flowi4));
3281 fl4->flowi4_mark = skb->mark;
3282 fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3283
3284 fl4->flowi4_proto = iph->protocol;
3285 fl4->daddr = reverse ? iph->saddr : iph->daddr;
3286 fl4->saddr = reverse ? iph->daddr : iph->saddr;
3287 fl4->flowi4_tos = iph->tos;
3288
3289 if (!ip_is_fragment(iph)) {
3290 switch (iph->protocol) {
3291 case IPPROTO_UDP:
3292 case IPPROTO_UDPLITE:
3293 case IPPROTO_TCP:
3294 case IPPROTO_SCTP:
3295 case IPPROTO_DCCP:
3296 if (xprth + 4 < skb->data ||
3297 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3298 __be16 *ports;
3299
3300 xprth = skb_network_header(skb) + ihl * 4;
3301 ports = (__be16 *)xprth;
3302
3303 fl4->fl4_sport = ports[!!reverse];
3304 fl4->fl4_dport = ports[!reverse];
3305 }
3306 break;
3307 case IPPROTO_ICMP:
3308 if (xprth + 2 < skb->data ||
3309 pskb_may_pull(skb, xprth + 2 - skb->data)) {
3310 u8 *icmp;
3311
3312 xprth = skb_network_header(skb) + ihl * 4;
3313 icmp = xprth;
3314
3315 fl4->fl4_icmp_type = icmp[0];
3316 fl4->fl4_icmp_code = icmp[1];
3317 }
3318 break;
3319 case IPPROTO_ESP:
3320 if (xprth + 4 < skb->data ||
3321 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3322 __be32 *ehdr;
3323
3324 xprth = skb_network_header(skb) + ihl * 4;
3325 ehdr = (__be32 *)xprth;
3326
3327 fl4->fl4_ipsec_spi = ehdr[0];
3328 }
3329 break;
3330 case IPPROTO_AH:
3331 if (xprth + 8 < skb->data ||
3332 pskb_may_pull(skb, xprth + 8 - skb->data)) {
3333 __be32 *ah_hdr;
3334
3335 xprth = skb_network_header(skb) + ihl * 4;
3336 ah_hdr = (__be32 *)xprth;
3337
3338 fl4->fl4_ipsec_spi = ah_hdr[1];
3339 }
3340 break;
3341 case IPPROTO_COMP:
3342 if (xprth + 4 < skb->data ||
3343 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3344 __be16 *ipcomp_hdr;
3345
3346 xprth = skb_network_header(skb) + ihl * 4;
3347 ipcomp_hdr = (__be16 *)xprth;
3348
3349 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
3350 }
3351 break;
3352 case IPPROTO_GRE:
3353 if (xprth + 12 < skb->data ||
3354 pskb_may_pull(skb, xprth + 12 - skb->data)) {
3355 __be16 *greflags;
3356 __be32 *gre_hdr;
3357
3358 xprth = skb_network_header(skb) + ihl * 4;
3359 greflags = (__be16 *)xprth;
3360 gre_hdr = (__be32 *)xprth;
3361
3362 if (greflags[0] & GRE_KEY) {
3363 if (greflags[0] & GRE_CSUM)
3364 gre_hdr++;
3365 fl4->fl4_gre_key = gre_hdr[1];
3366 }
3367 }
3368 break;
3369 default:
3370 fl4->fl4_ipsec_spi = 0;
3371 break;
3372 }
3373 }
3374 }
3375
3376 #if IS_ENABLED(CONFIG_IPV6)
3377 static void
3378 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3379 {
3380 struct flowi6 *fl6 = &fl->u.ip6;
3381 int onlyproto = 0;
3382 const struct ipv6hdr *hdr = ipv6_hdr(skb);
3383 u32 offset = sizeof(*hdr);
3384 struct ipv6_opt_hdr *exthdr;
3385 const unsigned char *nh = skb_network_header(skb);
3386 u16 nhoff = IP6CB(skb)->nhoff;
3387 int oif = 0;
3388 u8 nexthdr;
3389
3390 if (!nhoff)
3391 nhoff = offsetof(struct ipv6hdr, nexthdr);
3392
3393 nexthdr = nh[nhoff];
3394
3395 if (skb_dst(skb) && skb_dst(skb)->dev)
3396 oif = skb_dst(skb)->dev->ifindex;
3397
3398 memset(fl6, 0, sizeof(struct flowi6));
3399 fl6->flowi6_mark = skb->mark;
3400 fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3401
3402 fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3403 fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3404
3405 while (nh + offset + sizeof(*exthdr) < skb->data ||
3406 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3407 nh = skb_network_header(skb);
3408 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3409
3410 switch (nexthdr) {
3411 case NEXTHDR_FRAGMENT:
3412 onlyproto = 1;
3413 fallthrough;
3414 case NEXTHDR_ROUTING:
3415 case NEXTHDR_HOP:
3416 case NEXTHDR_DEST:
3417 offset += ipv6_optlen(exthdr);
3418 nexthdr = exthdr->nexthdr;
3419 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3420 break;
3421 case IPPROTO_UDP:
3422 case IPPROTO_UDPLITE:
3423 case IPPROTO_TCP:
3424 case IPPROTO_SCTP:
3425 case IPPROTO_DCCP:
3426 if (!onlyproto && (nh + offset + 4 < skb->data ||
3427 pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3428 __be16 *ports;
3429
3430 nh = skb_network_header(skb);
3431 ports = (__be16 *)(nh + offset);
3432 fl6->fl6_sport = ports[!!reverse];
3433 fl6->fl6_dport = ports[!reverse];
3434 }
3435 fl6->flowi6_proto = nexthdr;
3436 return;
3437 case IPPROTO_ICMPV6:
3438 if (!onlyproto && (nh + offset + 2 < skb->data ||
3439 pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3440 u8 *icmp;
3441
3442 nh = skb_network_header(skb);
3443 icmp = (u8 *)(nh + offset);
3444 fl6->fl6_icmp_type = icmp[0];
3445 fl6->fl6_icmp_code = icmp[1];
3446 }
3447 fl6->flowi6_proto = nexthdr;
3448 return;
3449 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3450 case IPPROTO_MH:
3451 offset += ipv6_optlen(exthdr);
3452 if (!onlyproto && (nh + offset + 3 < skb->data ||
3453 pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3454 struct ip6_mh *mh;
3455
3456 nh = skb_network_header(skb);
3457 mh = (struct ip6_mh *)(nh + offset);
3458 fl6->fl6_mh_type = mh->ip6mh_type;
3459 }
3460 fl6->flowi6_proto = nexthdr;
3461 return;
3462 #endif
3463 /* XXX Why are there these headers? */
3464 case IPPROTO_AH:
3465 case IPPROTO_ESP:
3466 case IPPROTO_COMP:
3467 default:
3468 fl6->fl6_ipsec_spi = 0;
3469 fl6->flowi6_proto = nexthdr;
3470 return;
3471 }
3472 }
3473 }
3474 #endif
3475
3476 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3477 unsigned int family, int reverse)
3478 {
3479 switch (family) {
3480 case AF_INET:
3481 decode_session4(skb, fl, reverse);
3482 break;
3483 #if IS_ENABLED(CONFIG_IPV6)
3484 case AF_INET6:
3485 decode_session6(skb, fl, reverse);
3486 break;
3487 #endif
3488 default:
3489 return -EAFNOSUPPORT;
3490 }
3491
3492 return security_xfrm_decode_session(skb, &fl->flowi_secid);
3493 }
3494 EXPORT_SYMBOL(__xfrm_decode_session);
3495
3496 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3497 {
3498 for (; k < sp->len; k++) {
3499 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3500 *idxp = k;
3501 return 1;
3502 }
3503 }
3504
3505 return 0;
3506 }
3507
3508 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3509 unsigned short family)
3510 {
3511 struct net *net = dev_net(skb->dev);
3512 struct xfrm_policy *pol;
3513 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3514 int npols = 0;
3515 int xfrm_nr;
3516 int pi;
3517 int reverse;
3518 struct flowi fl;
3519 int xerr_idx = -1;
3520 const struct xfrm_if_cb *ifcb;
3521 struct sec_path *sp;
3522 struct xfrm_if *xi;
3523 u32 if_id = 0;
3524
3525 rcu_read_lock();
3526 ifcb = xfrm_if_get_cb();
3527
3528 if (ifcb) {
3529 xi = ifcb->decode_session(skb, family);
3530 if (xi) {
3531 if_id = xi->p.if_id;
3532 net = xi->net;
3533 }
3534 }
3535 rcu_read_unlock();
3536
3537 reverse = dir & ~XFRM_POLICY_MASK;
3538 dir &= XFRM_POLICY_MASK;
3539
3540 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3541 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3542 return 0;
3543 }
3544
3545 nf_nat_decode_session(skb, &fl, family);
3546
3547 /* First, check used SA against their selectors. */
3548 sp = skb_sec_path(skb);
3549 if (sp) {
3550 int i;
3551
3552 for (i = sp->len - 1; i >= 0; i--) {
3553 struct xfrm_state *x = sp->xvec[i];
3554 if (!xfrm_selector_match(&x->sel, &fl, family)) {
3555 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3556 return 0;
3557 }
3558 }
3559 }
3560
3561 pol = NULL;
3562 sk = sk_to_full_sk(sk);
3563 if (sk && sk->sk_policy[dir]) {
3564 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3565 if (IS_ERR(pol)) {
3566 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3567 return 0;
3568 }
3569 }
3570
3571 if (!pol)
3572 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3573
3574 if (IS_ERR(pol)) {
3575 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3576 return 0;
3577 }
3578
3579 if (!pol) {
3580 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3581 xfrm_secpath_reject(xerr_idx, skb, &fl);
3582 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3583 return 0;
3584 }
3585 return 1;
3586 }
3587
3588 pol->curlft.use_time = ktime_get_real_seconds();
3589
3590 pols[0] = pol;
3591 npols++;
3592 #ifdef CONFIG_XFRM_SUB_POLICY
3593 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3594 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3595 &fl, family,
3596 XFRM_POLICY_IN, if_id);
3597 if (pols[1]) {
3598 if (IS_ERR(pols[1])) {
3599 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3600 return 0;
3601 }
3602 pols[1]->curlft.use_time = ktime_get_real_seconds();
3603 npols++;
3604 }
3605 }
3606 #endif
3607
3608 if (pol->action == XFRM_POLICY_ALLOW) {
3609 static struct sec_path dummy;
3610 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3611 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3612 struct xfrm_tmpl **tpp = tp;
3613 int ti = 0;
3614 int i, k;
3615
3616 sp = skb_sec_path(skb);
3617 if (!sp)
3618 sp = &dummy;
3619
3620 for (pi = 0; pi < npols; pi++) {
3621 if (pols[pi] != pol &&
3622 pols[pi]->action != XFRM_POLICY_ALLOW) {
3623 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3624 goto reject;
3625 }
3626 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3627 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3628 goto reject_error;
3629 }
3630 for (i = 0; i < pols[pi]->xfrm_nr; i++)
3631 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3632 }
3633 xfrm_nr = ti;
3634 if (npols > 1) {
3635 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3636 tpp = stp;
3637 }
3638
3639 /* For each tunnel xfrm, find the first matching tmpl.
3640 * For each tmpl before that, find corresponding xfrm.
3641 * Order is _important_. Later we will implement
3642 * some barriers, but at the moment barriers
3643 * are implied between each two transformations.
3644 */
3645 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3646 k = xfrm_policy_ok(tpp[i], sp, k, family);
3647 if (k < 0) {
3648 if (k < -1)
3649 /* "-2 - errored_index" returned */
3650 xerr_idx = -(2+k);
3651 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3652 goto reject;
3653 }
3654 }
3655
3656 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3657 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3658 goto reject;
3659 }
3660
3661 xfrm_pols_put(pols, npols);
3662 return 1;
3663 }
3664 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3665
3666 reject:
3667 xfrm_secpath_reject(xerr_idx, skb, &fl);
3668 reject_error:
3669 xfrm_pols_put(pols, npols);
3670 return 0;
3671 }
3672 EXPORT_SYMBOL(__xfrm_policy_check);
3673
3674 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3675 {
3676 struct net *net = dev_net(skb->dev);
3677 struct flowi fl;
3678 struct dst_entry *dst;
3679 int res = 1;
3680
3681 if (xfrm_decode_session(skb, &fl, family) < 0) {
3682 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3683 return 0;
3684 }
3685
3686 skb_dst_force(skb);
3687 if (!skb_dst(skb)) {
3688 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3689 return 0;
3690 }
3691
3692 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3693 if (IS_ERR(dst)) {
3694 res = 0;
3695 dst = NULL;
3696 }
3697 skb_dst_set(skb, dst);
3698 return res;
3699 }
3700 EXPORT_SYMBOL(__xfrm_route_forward);
3701
3702 /* Optimize later using cookies and generation ids. */
3703
3704 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3705 {
3706 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3707 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3708 * get validated by dst_ops->check on every use. We do this
3709 * because when a normal route referenced by an XFRM dst is
3710 * obsoleted we do not go looking around for all parent
3711 * referencing XFRM dsts so that we can invalidate them. It
3712 * is just too much work. Instead we make the checks here on
3713 * every use. For example:
3714 *
3715 * XFRM dst A --> IPv4 dst X
3716 *
3717 * X is the "xdst->route" of A (X is also the "dst->path" of A
3718 * in this example). If X is marked obsolete, "A" will not
3719 * notice. That's what we are validating here via the
3720 * stale_bundle() check.
3721 *
3722 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3723 * be marked on it.
3724 * This will force stale_bundle() to fail on any xdst bundle with
3725 * this dst linked in it.
3726 */
3727 if (dst->obsolete < 0 && !stale_bundle(dst))
3728 return dst;
3729
3730 return NULL;
3731 }
3732
3733 static int stale_bundle(struct dst_entry *dst)
3734 {
3735 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3736 }
3737
3738 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3739 {
3740 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3741 dst->dev = dev_net(dev)->loopback_dev;
3742 dev_hold(dst->dev);
3743 dev_put(dev);
3744 }
3745 }
3746 EXPORT_SYMBOL(xfrm_dst_ifdown);
3747
3748 static void xfrm_link_failure(struct sk_buff *skb)
3749 {
3750 /* Impossible. Such dst must be popped before reaches point of failure. */
3751 }
3752
3753 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3754 {
3755 if (dst) {
3756 if (dst->obsolete) {
3757 dst_release(dst);
3758 dst = NULL;
3759 }
3760 }
3761 return dst;
3762 }
3763
3764 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3765 {
3766 while (nr--) {
3767 struct xfrm_dst *xdst = bundle[nr];
3768 u32 pmtu, route_mtu_cached;
3769 struct dst_entry *dst;
3770
3771 dst = &xdst->u.dst;
3772 pmtu = dst_mtu(xfrm_dst_child(dst));
3773 xdst->child_mtu_cached = pmtu;
3774
3775 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3776
3777 route_mtu_cached = dst_mtu(xdst->route);
3778 xdst->route_mtu_cached = route_mtu_cached;
3779
3780 if (pmtu > route_mtu_cached)
3781 pmtu = route_mtu_cached;
3782
3783 dst_metric_set(dst, RTAX_MTU, pmtu);
3784 }
3785 }
3786
3787 /* Check that the bundle accepts the flow and its components are
3788 * still valid.
3789 */
3790
3791 static int xfrm_bundle_ok(struct xfrm_dst *first)
3792 {
3793 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3794 struct dst_entry *dst = &first->u.dst;
3795 struct xfrm_dst *xdst;
3796 int start_from, nr;
3797 u32 mtu;
3798
3799 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3800 (dst->dev && !netif_running(dst->dev)))
3801 return 0;
3802
3803 if (dst->flags & DST_XFRM_QUEUE)
3804 return 1;
3805
3806 start_from = nr = 0;
3807 do {
3808 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3809
3810 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3811 return 0;
3812 if (xdst->xfrm_genid != dst->xfrm->genid)
3813 return 0;
3814 if (xdst->num_pols > 0 &&
3815 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3816 return 0;
3817
3818 bundle[nr++] = xdst;
3819
3820 mtu = dst_mtu(xfrm_dst_child(dst));
3821 if (xdst->child_mtu_cached != mtu) {
3822 start_from = nr;
3823 xdst->child_mtu_cached = mtu;
3824 }
3825
3826 if (!dst_check(xdst->route, xdst->route_cookie))
3827 return 0;
3828 mtu = dst_mtu(xdst->route);
3829 if (xdst->route_mtu_cached != mtu) {
3830 start_from = nr;
3831 xdst->route_mtu_cached = mtu;
3832 }
3833
3834 dst = xfrm_dst_child(dst);
3835 } while (dst->xfrm);
3836
3837 if (likely(!start_from))
3838 return 1;
3839
3840 xdst = bundle[start_from - 1];
3841 mtu = xdst->child_mtu_cached;
3842 while (start_from--) {
3843 dst = &xdst->u.dst;
3844
3845 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3846 if (mtu > xdst->route_mtu_cached)
3847 mtu = xdst->route_mtu_cached;
3848 dst_metric_set(dst, RTAX_MTU, mtu);
3849 if (!start_from)
3850 break;
3851
3852 xdst = bundle[start_from - 1];
3853 xdst->child_mtu_cached = mtu;
3854 }
3855
3856 return 1;
3857 }
3858
3859 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3860 {
3861 return dst_metric_advmss(xfrm_dst_path(dst));
3862 }
3863
3864 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3865 {
3866 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3867
3868 return mtu ? : dst_mtu(xfrm_dst_path(dst));
3869 }
3870
3871 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3872 const void *daddr)
3873 {
3874 while (dst->xfrm) {
3875 const struct xfrm_state *xfrm = dst->xfrm;
3876
3877 dst = xfrm_dst_child(dst);
3878
3879 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3880 continue;
3881 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3882 daddr = xfrm->coaddr;
3883 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3884 daddr = &xfrm->id.daddr;
3885 }
3886 return daddr;
3887 }
3888
3889 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3890 struct sk_buff *skb,
3891 const void *daddr)
3892 {
3893 const struct dst_entry *path = xfrm_dst_path(dst);
3894
3895 if (!skb)
3896 daddr = xfrm_get_dst_nexthop(dst, daddr);
3897 return path->ops->neigh_lookup(path, skb, daddr);
3898 }
3899
3900 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3901 {
3902 const struct dst_entry *path = xfrm_dst_path(dst);
3903
3904 daddr = xfrm_get_dst_nexthop(dst, daddr);
3905 path->ops->confirm_neigh(path, daddr);
3906 }
3907
3908 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3909 {
3910 int err = 0;
3911
3912 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3913 return -EAFNOSUPPORT;
3914
3915 spin_lock(&xfrm_policy_afinfo_lock);
3916 if (unlikely(xfrm_policy_afinfo[family] != NULL))
3917 err = -EEXIST;
3918 else {
3919 struct dst_ops *dst_ops = afinfo->dst_ops;
3920 if (likely(dst_ops->kmem_cachep == NULL))
3921 dst_ops->kmem_cachep = xfrm_dst_cache;
3922 if (likely(dst_ops->check == NULL))
3923 dst_ops->check = xfrm_dst_check;
3924 if (likely(dst_ops->default_advmss == NULL))
3925 dst_ops->default_advmss = xfrm_default_advmss;
3926 if (likely(dst_ops->mtu == NULL))
3927 dst_ops->mtu = xfrm_mtu;
3928 if (likely(dst_ops->negative_advice == NULL))
3929 dst_ops->negative_advice = xfrm_negative_advice;
3930 if (likely(dst_ops->link_failure == NULL))
3931 dst_ops->link_failure = xfrm_link_failure;
3932 if (likely(dst_ops->neigh_lookup == NULL))
3933 dst_ops->neigh_lookup = xfrm_neigh_lookup;
3934 if (likely(!dst_ops->confirm_neigh))
3935 dst_ops->confirm_neigh = xfrm_confirm_neigh;
3936 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
3937 }
3938 spin_unlock(&xfrm_policy_afinfo_lock);
3939
3940 return err;
3941 }
3942 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
3943
3944 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
3945 {
3946 struct dst_ops *dst_ops = afinfo->dst_ops;
3947 int i;
3948
3949 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
3950 if (xfrm_policy_afinfo[i] != afinfo)
3951 continue;
3952 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
3953 break;
3954 }
3955
3956 synchronize_rcu();
3957
3958 dst_ops->kmem_cachep = NULL;
3959 dst_ops->check = NULL;
3960 dst_ops->negative_advice = NULL;
3961 dst_ops->link_failure = NULL;
3962 }
3963 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
3964
3965 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
3966 {
3967 spin_lock(&xfrm_if_cb_lock);
3968 rcu_assign_pointer(xfrm_if_cb, ifcb);
3969 spin_unlock(&xfrm_if_cb_lock);
3970 }
3971 EXPORT_SYMBOL(xfrm_if_register_cb);
3972
3973 void xfrm_if_unregister_cb(void)
3974 {
3975 RCU_INIT_POINTER(xfrm_if_cb, NULL);
3976 synchronize_rcu();
3977 }
3978 EXPORT_SYMBOL(xfrm_if_unregister_cb);
3979
3980 #ifdef CONFIG_XFRM_STATISTICS
3981 static int __net_init xfrm_statistics_init(struct net *net)
3982 {
3983 int rv;
3984 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
3985 if (!net->mib.xfrm_statistics)
3986 return -ENOMEM;
3987 rv = xfrm_proc_init(net);
3988 if (rv < 0)
3989 free_percpu(net->mib.xfrm_statistics);
3990 return rv;
3991 }
3992
3993 static void xfrm_statistics_fini(struct net *net)
3994 {
3995 xfrm_proc_fini(net);
3996 free_percpu(net->mib.xfrm_statistics);
3997 }
3998 #else
3999 static int __net_init xfrm_statistics_init(struct net *net)
4000 {
4001 return 0;
4002 }
4003
4004 static void xfrm_statistics_fini(struct net *net)
4005 {
4006 }
4007 #endif
4008
4009 static int __net_init xfrm_policy_init(struct net *net)
4010 {
4011 unsigned int hmask, sz;
4012 int dir, err;
4013
4014 if (net_eq(net, &init_net)) {
4015 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4016 sizeof(struct xfrm_dst),
4017 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4018 NULL);
4019 err = rhashtable_init(&xfrm_policy_inexact_table,
4020 &xfrm_pol_inexact_params);
4021 BUG_ON(err);
4022 }
4023
4024 hmask = 8 - 1;
4025 sz = (hmask+1) * sizeof(struct hlist_head);
4026
4027 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4028 if (!net->xfrm.policy_byidx)
4029 goto out_byidx;
4030 net->xfrm.policy_idx_hmask = hmask;
4031
4032 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4033 struct xfrm_policy_hash *htab;
4034
4035 net->xfrm.policy_count[dir] = 0;
4036 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4037 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4038
4039 htab = &net->xfrm.policy_bydst[dir];
4040 htab->table = xfrm_hash_alloc(sz);
4041 if (!htab->table)
4042 goto out_bydst;
4043 htab->hmask = hmask;
4044 htab->dbits4 = 32;
4045 htab->sbits4 = 32;
4046 htab->dbits6 = 128;
4047 htab->sbits6 = 128;
4048 }
4049 net->xfrm.policy_hthresh.lbits4 = 32;
4050 net->xfrm.policy_hthresh.rbits4 = 32;
4051 net->xfrm.policy_hthresh.lbits6 = 128;
4052 net->xfrm.policy_hthresh.rbits6 = 128;
4053
4054 seqlock_init(&net->xfrm.policy_hthresh.lock);
4055
4056 INIT_LIST_HEAD(&net->xfrm.policy_all);
4057 INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4058 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4059 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4060 return 0;
4061
4062 out_bydst:
4063 for (dir--; dir >= 0; dir--) {
4064 struct xfrm_policy_hash *htab;
4065
4066 htab = &net->xfrm.policy_bydst[dir];
4067 xfrm_hash_free(htab->table, sz);
4068 }
4069 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4070 out_byidx:
4071 return -ENOMEM;
4072 }
4073
4074 static void xfrm_policy_fini(struct net *net)
4075 {
4076 struct xfrm_pol_inexact_bin *b, *t;
4077 unsigned int sz;
4078 int dir;
4079
4080 flush_work(&net->xfrm.policy_hash_work);
4081 #ifdef CONFIG_XFRM_SUB_POLICY
4082 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4083 #endif
4084 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4085
4086 WARN_ON(!list_empty(&net->xfrm.policy_all));
4087
4088 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4089 struct xfrm_policy_hash *htab;
4090
4091 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4092
4093 htab = &net->xfrm.policy_bydst[dir];
4094 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4095 WARN_ON(!hlist_empty(htab->table));
4096 xfrm_hash_free(htab->table, sz);
4097 }
4098
4099 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4100 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4101 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4102
4103 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4104 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4105 __xfrm_policy_inexact_prune_bin(b, true);
4106 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4107 }
4108
4109 static int __net_init xfrm_net_init(struct net *net)
4110 {
4111 int rv;
4112
4113 /* Initialize the per-net locks here */
4114 spin_lock_init(&net->xfrm.xfrm_state_lock);
4115 spin_lock_init(&net->xfrm.xfrm_policy_lock);
4116 mutex_init(&net->xfrm.xfrm_cfg_mutex);
4117
4118 rv = xfrm_statistics_init(net);
4119 if (rv < 0)
4120 goto out_statistics;
4121 rv = xfrm_state_init(net);
4122 if (rv < 0)
4123 goto out_state;
4124 rv = xfrm_policy_init(net);
4125 if (rv < 0)
4126 goto out_policy;
4127 rv = xfrm_sysctl_init(net);
4128 if (rv < 0)
4129 goto out_sysctl;
4130
4131 return 0;
4132
4133 out_sysctl:
4134 xfrm_policy_fini(net);
4135 out_policy:
4136 xfrm_state_fini(net);
4137 out_state:
4138 xfrm_statistics_fini(net);
4139 out_statistics:
4140 return rv;
4141 }
4142
4143 static void __net_exit xfrm_net_exit(struct net *net)
4144 {
4145 xfrm_sysctl_fini(net);
4146 xfrm_policy_fini(net);
4147 xfrm_state_fini(net);
4148 xfrm_statistics_fini(net);
4149 }
4150
4151 static struct pernet_operations __net_initdata xfrm_net_ops = {
4152 .init = xfrm_net_init,
4153 .exit = xfrm_net_exit,
4154 };
4155
4156 void __init xfrm_init(void)
4157 {
4158 register_pernet_subsys(&xfrm_net_ops);
4159 xfrm_dev_init();
4160 seqcount_mutex_init(&xfrm_policy_hash_generation, &hash_resize_mutex);
4161 xfrm_input_init();
4162
4163 #ifdef CONFIG_XFRM_ESPINTCP
4164 espintcp_init();
4165 #endif
4166
4167 RCU_INIT_POINTER(xfrm_if_cb, NULL);
4168 synchronize_rcu();
4169 }
4170
4171 #ifdef CONFIG_AUDITSYSCALL
4172 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4173 struct audit_buffer *audit_buf)
4174 {
4175 struct xfrm_sec_ctx *ctx = xp->security;
4176 struct xfrm_selector *sel = &xp->selector;
4177
4178 if (ctx)
4179 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4180 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4181
4182 switch (sel->family) {
4183 case AF_INET:
4184 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4185 if (sel->prefixlen_s != 32)
4186 audit_log_format(audit_buf, " src_prefixlen=%d",
4187 sel->prefixlen_s);
4188 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4189 if (sel->prefixlen_d != 32)
4190 audit_log_format(audit_buf, " dst_prefixlen=%d",
4191 sel->prefixlen_d);
4192 break;
4193 case AF_INET6:
4194 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4195 if (sel->prefixlen_s != 128)
4196 audit_log_format(audit_buf, " src_prefixlen=%d",
4197 sel->prefixlen_s);
4198 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4199 if (sel->prefixlen_d != 128)
4200 audit_log_format(audit_buf, " dst_prefixlen=%d",
4201 sel->prefixlen_d);
4202 break;
4203 }
4204 }
4205
4206 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4207 {
4208 struct audit_buffer *audit_buf;
4209
4210 audit_buf = xfrm_audit_start("SPD-add");
4211 if (audit_buf == NULL)
4212 return;
4213 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4214 audit_log_format(audit_buf, " res=%u", result);
4215 xfrm_audit_common_policyinfo(xp, audit_buf);
4216 audit_log_end(audit_buf);
4217 }
4218 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4219
4220 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4221 bool task_valid)
4222 {
4223 struct audit_buffer *audit_buf;
4224
4225 audit_buf = xfrm_audit_start("SPD-delete");
4226 if (audit_buf == NULL)
4227 return;
4228 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4229 audit_log_format(audit_buf, " res=%u", result);
4230 xfrm_audit_common_policyinfo(xp, audit_buf);
4231 audit_log_end(audit_buf);
4232 }
4233 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4234 #endif
4235
4236 #ifdef CONFIG_XFRM_MIGRATE
4237 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4238 const struct xfrm_selector *sel_tgt)
4239 {
4240 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4241 if (sel_tgt->family == sel_cmp->family &&
4242 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4243 sel_cmp->family) &&
4244 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4245 sel_cmp->family) &&
4246 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4247 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4248 return true;
4249 }
4250 } else {
4251 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4252 return true;
4253 }
4254 }
4255 return false;
4256 }
4257
4258 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4259 u8 dir, u8 type, struct net *net)
4260 {
4261 struct xfrm_policy *pol, *ret = NULL;
4262 struct hlist_head *chain;
4263 u32 priority = ~0U;
4264
4265 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4266 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4267 hlist_for_each_entry(pol, chain, bydst) {
4268 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4269 pol->type == type) {
4270 ret = pol;
4271 priority = ret->priority;
4272 break;
4273 }
4274 }
4275 chain = &net->xfrm.policy_inexact[dir];
4276 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4277 if ((pol->priority >= priority) && ret)
4278 break;
4279
4280 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4281 pol->type == type) {
4282 ret = pol;
4283 break;
4284 }
4285 }
4286
4287 xfrm_pol_hold(ret);
4288
4289 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4290
4291 return ret;
4292 }
4293
4294 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4295 {
4296 int match = 0;
4297
4298 if (t->mode == m->mode && t->id.proto == m->proto &&
4299 (m->reqid == 0 || t->reqid == m->reqid)) {
4300 switch (t->mode) {
4301 case XFRM_MODE_TUNNEL:
4302 case XFRM_MODE_BEET:
4303 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4304 m->old_family) &&
4305 xfrm_addr_equal(&t->saddr, &m->old_saddr,
4306 m->old_family)) {
4307 match = 1;
4308 }
4309 break;
4310 case XFRM_MODE_TRANSPORT:
4311 /* in case of transport mode, template does not store
4312 any IP addresses, hence we just compare mode and
4313 protocol */
4314 match = 1;
4315 break;
4316 default:
4317 break;
4318 }
4319 }
4320 return match;
4321 }
4322
4323 /* update endpoint address(es) of template(s) */
4324 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4325 struct xfrm_migrate *m, int num_migrate)
4326 {
4327 struct xfrm_migrate *mp;
4328 int i, j, n = 0;
4329
4330 write_lock_bh(&pol->lock);
4331 if (unlikely(pol->walk.dead)) {
4332 /* target policy has been deleted */
4333 write_unlock_bh(&pol->lock);
4334 return -ENOENT;
4335 }
4336
4337 for (i = 0; i < pol->xfrm_nr; i++) {
4338 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4339 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4340 continue;
4341 n++;
4342 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4343 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4344 continue;
4345 /* update endpoints */
4346 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4347 sizeof(pol->xfrm_vec[i].id.daddr));
4348 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4349 sizeof(pol->xfrm_vec[i].saddr));
4350 pol->xfrm_vec[i].encap_family = mp->new_family;
4351 /* flush bundles */
4352 atomic_inc(&pol->genid);
4353 }
4354 }
4355
4356 write_unlock_bh(&pol->lock);
4357
4358 if (!n)
4359 return -ENODATA;
4360
4361 return 0;
4362 }
4363
4364 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
4365 {
4366 int i, j;
4367
4368 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
4369 return -EINVAL;
4370
4371 for (i = 0; i < num_migrate; i++) {
4372 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4373 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
4374 return -EINVAL;
4375
4376 /* check if there is any duplicated entry */
4377 for (j = i + 1; j < num_migrate; j++) {
4378 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4379 sizeof(m[i].old_daddr)) &&
4380 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4381 sizeof(m[i].old_saddr)) &&
4382 m[i].proto == m[j].proto &&
4383 m[i].mode == m[j].mode &&
4384 m[i].reqid == m[j].reqid &&
4385 m[i].old_family == m[j].old_family)
4386 return -EINVAL;
4387 }
4388 }
4389
4390 return 0;
4391 }
4392
4393 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4394 struct xfrm_migrate *m, int num_migrate,
4395 struct xfrm_kmaddress *k, struct net *net,
4396 struct xfrm_encap_tmpl *encap)
4397 {
4398 int i, err, nx_cur = 0, nx_new = 0;
4399 struct xfrm_policy *pol = NULL;
4400 struct xfrm_state *x, *xc;
4401 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4402 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4403 struct xfrm_migrate *mp;
4404
4405 /* Stage 0 - sanity checks */
4406 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
4407 goto out;
4408
4409 if (dir >= XFRM_POLICY_MAX) {
4410 err = -EINVAL;
4411 goto out;
4412 }
4413
4414 /* Stage 1 - find policy */
4415 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
4416 err = -ENOENT;
4417 goto out;
4418 }
4419
4420 /* Stage 2 - find and update state(s) */
4421 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4422 if ((x = xfrm_migrate_state_find(mp, net))) {
4423 x_cur[nx_cur] = x;
4424 nx_cur++;
4425 xc = xfrm_state_migrate(x, mp, encap);
4426 if (xc) {
4427 x_new[nx_new] = xc;
4428 nx_new++;
4429 } else {
4430 err = -ENODATA;
4431 goto restore_state;
4432 }
4433 }
4434 }
4435
4436 /* Stage 3 - update policy */
4437 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
4438 goto restore_state;
4439
4440 /* Stage 4 - delete old state(s) */
4441 if (nx_cur) {
4442 xfrm_states_put(x_cur, nx_cur);
4443 xfrm_states_delete(x_cur, nx_cur);
4444 }
4445
4446 /* Stage 5 - announce */
4447 km_migrate(sel, dir, type, m, num_migrate, k, encap);
4448
4449 xfrm_pol_put(pol);
4450
4451 return 0;
4452 out:
4453 return err;
4454
4455 restore_state:
4456 if (pol)
4457 xfrm_pol_put(pol);
4458 if (nx_cur)
4459 xfrm_states_put(x_cur, nx_cur);
4460 if (nx_new)
4461 xfrm_states_delete(x_new, nx_new);
4462
4463 return err;
4464 }
4465 EXPORT_SYMBOL(xfrm_migrate);
4466 #endif
Linux with added FPC-III support