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Linux 5.7.7
[linux/fpc-iii.git] / net / xfrm / xfrm_policy.c
blob564aa6492e7c397312f51e350a84b2063c5ed616
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_INET_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_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_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_init(&bin->count);
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 bool xfrm_policy_mark_match(struct xfrm_policy *policy,
1437 struct xfrm_policy *pol)
1438 {
1439 if (policy->mark.v == pol->mark.v &&
1440 policy->priority == pol->priority)
1441 return true;
1442
1443 return false;
1444 }
1445
1446 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1447 {
1448 const struct xfrm_pol_inexact_key *k = data;
1449 u32 a = k->type << 24 | k->dir << 16 | k->family;
1450
1451 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1452 seed);
1453 }
1454
1455 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1456 {
1457 const struct xfrm_pol_inexact_bin *b = data;
1458
1459 return xfrm_pol_bin_key(&b->k, 0, seed);
1460 }
1461
1462 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1463 const void *ptr)
1464 {
1465 const struct xfrm_pol_inexact_key *key = arg->key;
1466 const struct xfrm_pol_inexact_bin *b = ptr;
1467 int ret;
1468
1469 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1470 return -1;
1471
1472 ret = b->k.dir ^ key->dir;
1473 if (ret)
1474 return ret;
1475
1476 ret = b->k.type ^ key->type;
1477 if (ret)
1478 return ret;
1479
1480 ret = b->k.family ^ key->family;
1481 if (ret)
1482 return ret;
1483
1484 return b->k.if_id ^ key->if_id;
1485 }
1486
1487 static const struct rhashtable_params xfrm_pol_inexact_params = {
1488 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head),
1489 .hashfn = xfrm_pol_bin_key,
1490 .obj_hashfn = xfrm_pol_bin_obj,
1491 .obj_cmpfn = xfrm_pol_bin_cmp,
1492 .automatic_shrinking = true,
1493 };
1494
1495 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1496 struct xfrm_policy *policy)
1497 {
1498 struct xfrm_policy *pol, *delpol = NULL;
1499 struct hlist_node *newpos = NULL;
1500 int i = 0;
1501
1502 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1503 if (pol->type == policy->type &&
1504 pol->if_id == policy->if_id &&
1505 !selector_cmp(&pol->selector, &policy->selector) &&
1506 xfrm_policy_mark_match(policy, pol) &&
1507 xfrm_sec_ctx_match(pol->security, policy->security) &&
1508 !WARN_ON(delpol)) {
1509 delpol = pol;
1510 if (policy->priority > pol->priority)
1511 continue;
1512 } else if (policy->priority >= pol->priority) {
1513 newpos = &pol->bydst_inexact_list;
1514 continue;
1515 }
1516 if (delpol)
1517 break;
1518 }
1519
1520 if (newpos)
1521 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1522 else
1523 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1524
1525 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1526 pol->pos = i;
1527 i++;
1528 }
1529 }
1530
1531 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1532 struct xfrm_policy *policy,
1533 bool excl)
1534 {
1535 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1536
1537 hlist_for_each_entry(pol, chain, bydst) {
1538 if (pol->type == policy->type &&
1539 pol->if_id == policy->if_id &&
1540 !selector_cmp(&pol->selector, &policy->selector) &&
1541 xfrm_policy_mark_match(policy, pol) &&
1542 xfrm_sec_ctx_match(pol->security, policy->security) &&
1543 !WARN_ON(delpol)) {
1544 if (excl)
1545 return ERR_PTR(-EEXIST);
1546 delpol = pol;
1547 if (policy->priority > pol->priority)
1548 continue;
1549 } else if (policy->priority >= pol->priority) {
1550 newpos = pol;
1551 continue;
1552 }
1553 if (delpol)
1554 break;
1555 }
1556
1557 if (newpos)
1558 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1559 else
1560 hlist_add_head_rcu(&policy->bydst, chain);
1561
1562 return delpol;
1563 }
1564
1565 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1566 {
1567 struct net *net = xp_net(policy);
1568 struct xfrm_policy *delpol;
1569 struct hlist_head *chain;
1570
1571 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1572 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1573 if (chain)
1574 delpol = xfrm_policy_insert_list(chain, policy, excl);
1575 else
1576 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1577
1578 if (IS_ERR(delpol)) {
1579 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1580 return PTR_ERR(delpol);
1581 }
1582
1583 __xfrm_policy_link(policy, dir);
1584
1585 /* After previous checking, family can either be AF_INET or AF_INET6 */
1586 if (policy->family == AF_INET)
1587 rt_genid_bump_ipv4(net);
1588 else
1589 rt_genid_bump_ipv6(net);
1590
1591 if (delpol) {
1592 xfrm_policy_requeue(delpol, policy);
1593 __xfrm_policy_unlink(delpol, dir);
1594 }
1595 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1596 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1597 policy->curlft.add_time = ktime_get_real_seconds();
1598 policy->curlft.use_time = 0;
1599 if (!mod_timer(&policy->timer, jiffies + HZ))
1600 xfrm_pol_hold(policy);
1601 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1602
1603 if (delpol)
1604 xfrm_policy_kill(delpol);
1605 else if (xfrm_bydst_should_resize(net, dir, NULL))
1606 schedule_work(&net->xfrm.policy_hash_work);
1607
1608 return 0;
1609 }
1610 EXPORT_SYMBOL(xfrm_policy_insert);
1611
1612 static struct xfrm_policy *
1613 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id,
1614 u8 type, int dir,
1615 struct xfrm_selector *sel,
1616 struct xfrm_sec_ctx *ctx)
1617 {
1618 struct xfrm_policy *pol;
1619
1620 if (!chain)
1621 return NULL;
1622
1623 hlist_for_each_entry(pol, chain, bydst) {
1624 if (pol->type == type &&
1625 pol->if_id == if_id &&
1626 (mark & pol->mark.m) == pol->mark.v &&
1627 !selector_cmp(sel, &pol->selector) &&
1628 xfrm_sec_ctx_match(ctx, pol->security))
1629 return pol;
1630 }
1631
1632 return NULL;
1633 }
1634
1635 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id,
1636 u8 type, int dir,
1637 struct xfrm_selector *sel,
1638 struct xfrm_sec_ctx *ctx, int delete,
1639 int *err)
1640 {
1641 struct xfrm_pol_inexact_bin *bin = NULL;
1642 struct xfrm_policy *pol, *ret = NULL;
1643 struct hlist_head *chain;
1644
1645 *err = 0;
1646 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1647 chain = policy_hash_bysel(net, sel, sel->family, dir);
1648 if (!chain) {
1649 struct xfrm_pol_inexact_candidates cand;
1650 int i;
1651
1652 bin = xfrm_policy_inexact_lookup(net, type,
1653 sel->family, dir, if_id);
1654 if (!bin) {
1655 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1656 return NULL;
1657 }
1658
1659 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1660 &sel->saddr,
1661 &sel->daddr)) {
1662 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1663 return NULL;
1664 }
1665
1666 pol = NULL;
1667 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1668 struct xfrm_policy *tmp;
1669
1670 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1671 if_id, type, dir,
1672 sel, ctx);
1673 if (!tmp)
1674 continue;
1675
1676 if (!pol || tmp->pos < pol->pos)
1677 pol = tmp;
1678 }
1679 } else {
1680 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1681 sel, ctx);
1682 }
1683
1684 if (pol) {
1685 xfrm_pol_hold(pol);
1686 if (delete) {
1687 *err = security_xfrm_policy_delete(pol->security);
1688 if (*err) {
1689 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1690 return pol;
1691 }
1692 __xfrm_policy_unlink(pol, dir);
1693 }
1694 ret = pol;
1695 }
1696 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1697
1698 if (ret && delete)
1699 xfrm_policy_kill(ret);
1700 if (bin && delete)
1701 xfrm_policy_inexact_prune_bin(bin);
1702 return ret;
1703 }
1704 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1705
1706 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id,
1707 u8 type, int dir, u32 id, int delete,
1708 int *err)
1709 {
1710 struct xfrm_policy *pol, *ret;
1711 struct hlist_head *chain;
1712
1713 *err = -ENOENT;
1714 if (xfrm_policy_id2dir(id) != dir)
1715 return NULL;
1716
1717 *err = 0;
1718 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1719 chain = net->xfrm.policy_byidx + idx_hash(net, id);
1720 ret = NULL;
1721 hlist_for_each_entry(pol, chain, byidx) {
1722 if (pol->type == type && pol->index == id &&
1723 pol->if_id == if_id &&
1724 (mark & pol->mark.m) == pol->mark.v) {
1725 xfrm_pol_hold(pol);
1726 if (delete) {
1727 *err = security_xfrm_policy_delete(
1728 pol->security);
1729 if (*err) {
1730 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1731 return pol;
1732 }
1733 __xfrm_policy_unlink(pol, dir);
1734 }
1735 ret = pol;
1736 break;
1737 }
1738 }
1739 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1740
1741 if (ret && delete)
1742 xfrm_policy_kill(ret);
1743 return ret;
1744 }
1745 EXPORT_SYMBOL(xfrm_policy_byid);
1746
1747 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1748 static inline int
1749 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1750 {
1751 struct xfrm_policy *pol;
1752 int err = 0;
1753
1754 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1755 if (pol->walk.dead ||
1756 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1757 pol->type != type)
1758 continue;
1759
1760 err = security_xfrm_policy_delete(pol->security);
1761 if (err) {
1762 xfrm_audit_policy_delete(pol, 0, task_valid);
1763 return err;
1764 }
1765 }
1766 return err;
1767 }
1768 #else
1769 static inline int
1770 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1771 {
1772 return 0;
1773 }
1774 #endif
1775
1776 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1777 {
1778 int dir, err = 0, cnt = 0;
1779 struct xfrm_policy *pol;
1780
1781 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1782
1783 err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1784 if (err)
1785 goto out;
1786
1787 again:
1788 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1789 dir = xfrm_policy_id2dir(pol->index);
1790 if (pol->walk.dead ||
1791 dir >= XFRM_POLICY_MAX ||
1792 pol->type != type)
1793 continue;
1794
1795 __xfrm_policy_unlink(pol, dir);
1796 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1797 cnt++;
1798 xfrm_audit_policy_delete(pol, 1, task_valid);
1799 xfrm_policy_kill(pol);
1800 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1801 goto again;
1802 }
1803 if (cnt)
1804 __xfrm_policy_inexact_flush(net);
1805 else
1806 err = -ESRCH;
1807 out:
1808 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1809 return err;
1810 }
1811 EXPORT_SYMBOL(xfrm_policy_flush);
1812
1813 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1814 int (*func)(struct xfrm_policy *, int, int, void*),
1815 void *data)
1816 {
1817 struct xfrm_policy *pol;
1818 struct xfrm_policy_walk_entry *x;
1819 int error = 0;
1820
1821 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1822 walk->type != XFRM_POLICY_TYPE_ANY)
1823 return -EINVAL;
1824
1825 if (list_empty(&walk->walk.all) && walk->seq != 0)
1826 return 0;
1827
1828 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1829 if (list_empty(&walk->walk.all))
1830 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1831 else
1832 x = list_first_entry(&walk->walk.all,
1833 struct xfrm_policy_walk_entry, all);
1834
1835 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1836 if (x->dead)
1837 continue;
1838 pol = container_of(x, struct xfrm_policy, walk);
1839 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1840 walk->type != pol->type)
1841 continue;
1842 error = func(pol, xfrm_policy_id2dir(pol->index),
1843 walk->seq, data);
1844 if (error) {
1845 list_move_tail(&walk->walk.all, &x->all);
1846 goto out;
1847 }
1848 walk->seq++;
1849 }
1850 if (walk->seq == 0) {
1851 error = -ENOENT;
1852 goto out;
1853 }
1854 list_del_init(&walk->walk.all);
1855 out:
1856 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1857 return error;
1858 }
1859 EXPORT_SYMBOL(xfrm_policy_walk);
1860
1861 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1862 {
1863 INIT_LIST_HEAD(&walk->walk.all);
1864 walk->walk.dead = 1;
1865 walk->type = type;
1866 walk->seq = 0;
1867 }
1868 EXPORT_SYMBOL(xfrm_policy_walk_init);
1869
1870 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1871 {
1872 if (list_empty(&walk->walk.all))
1873 return;
1874
1875 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1876 list_del(&walk->walk.all);
1877 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1878 }
1879 EXPORT_SYMBOL(xfrm_policy_walk_done);
1880
1881 /*
1882 * Find policy to apply to this flow.
1883 *
1884 * Returns 0 if policy found, else an -errno.
1885 */
1886 static int xfrm_policy_match(const struct xfrm_policy *pol,
1887 const struct flowi *fl,
1888 u8 type, u16 family, int dir, u32 if_id)
1889 {
1890 const struct xfrm_selector *sel = &pol->selector;
1891 int ret = -ESRCH;
1892 bool match;
1893
1894 if (pol->family != family ||
1895 pol->if_id != if_id ||
1896 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1897 pol->type != type)
1898 return ret;
1899
1900 match = xfrm_selector_match(sel, fl, family);
1901 if (match)
1902 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1903 dir);
1904 return ret;
1905 }
1906
1907 static struct xfrm_pol_inexact_node *
1908 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1909 seqcount_t *count,
1910 const xfrm_address_t *addr, u16 family)
1911 {
1912 const struct rb_node *parent;
1913 int seq;
1914
1915 again:
1916 seq = read_seqcount_begin(count);
1917
1918 parent = rcu_dereference_raw(r->rb_node);
1919 while (parent) {
1920 struct xfrm_pol_inexact_node *node;
1921 int delta;
1922
1923 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
1924
1925 delta = xfrm_policy_addr_delta(addr, &node->addr,
1926 node->prefixlen, family);
1927 if (delta < 0) {
1928 parent = rcu_dereference_raw(parent->rb_left);
1929 continue;
1930 } else if (delta > 0) {
1931 parent = rcu_dereference_raw(parent->rb_right);
1932 continue;
1933 }
1934
1935 return node;
1936 }
1937
1938 if (read_seqcount_retry(count, seq))
1939 goto again;
1940
1941 return NULL;
1942 }
1943
1944 static bool
1945 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
1946 struct xfrm_pol_inexact_bin *b,
1947 const xfrm_address_t *saddr,
1948 const xfrm_address_t *daddr)
1949 {
1950 struct xfrm_pol_inexact_node *n;
1951 u16 family;
1952
1953 if (!b)
1954 return false;
1955
1956 family = b->k.family;
1957 memset(cand, 0, sizeof(*cand));
1958 cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
1959
1960 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
1961 family);
1962 if (n) {
1963 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
1964 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
1965 family);
1966 if (n)
1967 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
1968 }
1969
1970 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
1971 family);
1972 if (n)
1973 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
1974
1975 return true;
1976 }
1977
1978 static struct xfrm_pol_inexact_bin *
1979 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
1980 u8 dir, u32 if_id)
1981 {
1982 struct xfrm_pol_inexact_key k = {
1983 .family = family,
1984 .type = type,
1985 .dir = dir,
1986 .if_id = if_id,
1987 };
1988
1989 write_pnet(&k.net, net);
1990
1991 return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
1992 xfrm_pol_inexact_params);
1993 }
1994
1995 static struct xfrm_pol_inexact_bin *
1996 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
1997 u8 dir, u32 if_id)
1998 {
1999 struct xfrm_pol_inexact_bin *bin;
2000
2001 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2002
2003 rcu_read_lock();
2004 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2005 rcu_read_unlock();
2006
2007 return bin;
2008 }
2009
2010 static struct xfrm_policy *
2011 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2012 struct xfrm_policy *prefer,
2013 const struct flowi *fl,
2014 u8 type, u16 family, int dir, u32 if_id)
2015 {
2016 u32 priority = prefer ? prefer->priority : ~0u;
2017 struct xfrm_policy *pol;
2018
2019 if (!chain)
2020 return NULL;
2021
2022 hlist_for_each_entry_rcu(pol, chain, bydst) {
2023 int err;
2024
2025 if (pol->priority > priority)
2026 break;
2027
2028 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2029 if (err) {
2030 if (err != -ESRCH)
2031 return ERR_PTR(err);
2032
2033 continue;
2034 }
2035
2036 if (prefer) {
2037 /* matches. Is it older than *prefer? */
2038 if (pol->priority == priority &&
2039 prefer->pos < pol->pos)
2040 return prefer;
2041 }
2042
2043 return pol;
2044 }
2045
2046 return NULL;
2047 }
2048
2049 static struct xfrm_policy *
2050 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2051 struct xfrm_policy *prefer,
2052 const struct flowi *fl,
2053 u8 type, u16 family, int dir, u32 if_id)
2054 {
2055 struct xfrm_policy *tmp;
2056 int i;
2057
2058 for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2059 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2060 prefer,
2061 fl, type, family, dir,
2062 if_id);
2063 if (!tmp)
2064 continue;
2065
2066 if (IS_ERR(tmp))
2067 return tmp;
2068 prefer = tmp;
2069 }
2070
2071 return prefer;
2072 }
2073
2074 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2075 const struct flowi *fl,
2076 u16 family, u8 dir,
2077 u32 if_id)
2078 {
2079 struct xfrm_pol_inexact_candidates cand;
2080 const xfrm_address_t *daddr, *saddr;
2081 struct xfrm_pol_inexact_bin *bin;
2082 struct xfrm_policy *pol, *ret;
2083 struct hlist_head *chain;
2084 unsigned int sequence;
2085 int err;
2086
2087 daddr = xfrm_flowi_daddr(fl, family);
2088 saddr = xfrm_flowi_saddr(fl, family);
2089 if (unlikely(!daddr || !saddr))
2090 return NULL;
2091
2092 rcu_read_lock();
2093 retry:
2094 do {
2095 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
2096 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2097 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
2098
2099 ret = NULL;
2100 hlist_for_each_entry_rcu(pol, chain, bydst) {
2101 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2102 if (err) {
2103 if (err == -ESRCH)
2104 continue;
2105 else {
2106 ret = ERR_PTR(err);
2107 goto fail;
2108 }
2109 } else {
2110 ret = pol;
2111 break;
2112 }
2113 }
2114 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2115 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2116 daddr))
2117 goto skip_inexact;
2118
2119 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2120 family, dir, if_id);
2121 if (pol) {
2122 ret = pol;
2123 if (IS_ERR(pol))
2124 goto fail;
2125 }
2126
2127 skip_inexact:
2128 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
2129 goto retry;
2130
2131 if (ret && !xfrm_pol_hold_rcu(ret))
2132 goto retry;
2133 fail:
2134 rcu_read_unlock();
2135
2136 return ret;
2137 }
2138
2139 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2140 const struct flowi *fl,
2141 u16 family, u8 dir, u32 if_id)
2142 {
2143 #ifdef CONFIG_XFRM_SUB_POLICY
2144 struct xfrm_policy *pol;
2145
2146 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2147 dir, if_id);
2148 if (pol != NULL)
2149 return pol;
2150 #endif
2151 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2152 dir, if_id);
2153 }
2154
2155 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2156 const struct flowi *fl,
2157 u16 family, u32 if_id)
2158 {
2159 struct xfrm_policy *pol;
2160
2161 rcu_read_lock();
2162 again:
2163 pol = rcu_dereference(sk->sk_policy[dir]);
2164 if (pol != NULL) {
2165 bool match;
2166 int err = 0;
2167
2168 if (pol->family != family) {
2169 pol = NULL;
2170 goto out;
2171 }
2172
2173 match = xfrm_selector_match(&pol->selector, fl, family);
2174 if (match) {
2175 if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
2176 pol->if_id != if_id) {
2177 pol = NULL;
2178 goto out;
2179 }
2180 err = security_xfrm_policy_lookup(pol->security,
2181 fl->flowi_secid,
2182 dir);
2183 if (!err) {
2184 if (!xfrm_pol_hold_rcu(pol))
2185 goto again;
2186 } else if (err == -ESRCH) {
2187 pol = NULL;
2188 } else {
2189 pol = ERR_PTR(err);
2190 }
2191 } else
2192 pol = NULL;
2193 }
2194 out:
2195 rcu_read_unlock();
2196 return pol;
2197 }
2198
2199 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2200 {
2201 struct net *net = xp_net(pol);
2202
2203 list_add(&pol->walk.all, &net->xfrm.policy_all);
2204 net->xfrm.policy_count[dir]++;
2205 xfrm_pol_hold(pol);
2206 }
2207
2208 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2209 int dir)
2210 {
2211 struct net *net = xp_net(pol);
2212
2213 if (list_empty(&pol->walk.all))
2214 return NULL;
2215
2216 /* Socket policies are not hashed. */
2217 if (!hlist_unhashed(&pol->bydst)) {
2218 hlist_del_rcu(&pol->bydst);
2219 hlist_del_init(&pol->bydst_inexact_list);
2220 hlist_del(&pol->byidx);
2221 }
2222
2223 list_del_init(&pol->walk.all);
2224 net->xfrm.policy_count[dir]--;
2225
2226 return pol;
2227 }
2228
2229 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2230 {
2231 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2232 }
2233
2234 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2235 {
2236 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2237 }
2238
2239 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2240 {
2241 struct net *net = xp_net(pol);
2242
2243 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2244 pol = __xfrm_policy_unlink(pol, dir);
2245 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2246 if (pol) {
2247 xfrm_policy_kill(pol);
2248 return 0;
2249 }
2250 return -ENOENT;
2251 }
2252 EXPORT_SYMBOL(xfrm_policy_delete);
2253
2254 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2255 {
2256 struct net *net = sock_net(sk);
2257 struct xfrm_policy *old_pol;
2258
2259 #ifdef CONFIG_XFRM_SUB_POLICY
2260 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2261 return -EINVAL;
2262 #endif
2263
2264 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2265 old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2266 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2267 if (pol) {
2268 pol->curlft.add_time = ktime_get_real_seconds();
2269 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2270 xfrm_sk_policy_link(pol, dir);
2271 }
2272 rcu_assign_pointer(sk->sk_policy[dir], pol);
2273 if (old_pol) {
2274 if (pol)
2275 xfrm_policy_requeue(old_pol, pol);
2276
2277 /* Unlinking succeeds always. This is the only function
2278 * allowed to delete or replace socket policy.
2279 */
2280 xfrm_sk_policy_unlink(old_pol, dir);
2281 }
2282 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2283
2284 if (old_pol) {
2285 xfrm_policy_kill(old_pol);
2286 }
2287 return 0;
2288 }
2289
2290 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2291 {
2292 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2293 struct net *net = xp_net(old);
2294
2295 if (newp) {
2296 newp->selector = old->selector;
2297 if (security_xfrm_policy_clone(old->security,
2298 &newp->security)) {
2299 kfree(newp);
2300 return NULL; /* ENOMEM */
2301 }
2302 newp->lft = old->lft;
2303 newp->curlft = old->curlft;
2304 newp->mark = old->mark;
2305 newp->if_id = old->if_id;
2306 newp->action = old->action;
2307 newp->flags = old->flags;
2308 newp->xfrm_nr = old->xfrm_nr;
2309 newp->index = old->index;
2310 newp->type = old->type;
2311 newp->family = old->family;
2312 memcpy(newp->xfrm_vec, old->xfrm_vec,
2313 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2314 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2315 xfrm_sk_policy_link(newp, dir);
2316 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2317 xfrm_pol_put(newp);
2318 }
2319 return newp;
2320 }
2321
2322 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2323 {
2324 const struct xfrm_policy *p;
2325 struct xfrm_policy *np;
2326 int i, ret = 0;
2327
2328 rcu_read_lock();
2329 for (i = 0; i < 2; i++) {
2330 p = rcu_dereference(osk->sk_policy[i]);
2331 if (p) {
2332 np = clone_policy(p, i);
2333 if (unlikely(!np)) {
2334 ret = -ENOMEM;
2335 break;
2336 }
2337 rcu_assign_pointer(sk->sk_policy[i], np);
2338 }
2339 }
2340 rcu_read_unlock();
2341 return ret;
2342 }
2343
2344 static int
2345 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2346 xfrm_address_t *remote, unsigned short family, u32 mark)
2347 {
2348 int err;
2349 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2350
2351 if (unlikely(afinfo == NULL))
2352 return -EINVAL;
2353 err = afinfo->get_saddr(net, oif, local, remote, mark);
2354 rcu_read_unlock();
2355 return err;
2356 }
2357
2358 /* Resolve list of templates for the flow, given policy. */
2359
2360 static int
2361 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2362 struct xfrm_state **xfrm, unsigned short family)
2363 {
2364 struct net *net = xp_net(policy);
2365 int nx;
2366 int i, error;
2367 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2368 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2369 xfrm_address_t tmp;
2370
2371 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2372 struct xfrm_state *x;
2373 xfrm_address_t *remote = daddr;
2374 xfrm_address_t *local = saddr;
2375 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2376
2377 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2378 tmpl->mode == XFRM_MODE_BEET) {
2379 remote = &tmpl->id.daddr;
2380 local = &tmpl->saddr;
2381 if (xfrm_addr_any(local, tmpl->encap_family)) {
2382 error = xfrm_get_saddr(net, fl->flowi_oif,
2383 &tmp, remote,
2384 tmpl->encap_family, 0);
2385 if (error)
2386 goto fail;
2387 local = &tmp;
2388 }
2389 }
2390
2391 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2392 family, policy->if_id);
2393
2394 if (x && x->km.state == XFRM_STATE_VALID) {
2395 xfrm[nx++] = x;
2396 daddr = remote;
2397 saddr = local;
2398 continue;
2399 }
2400 if (x) {
2401 error = (x->km.state == XFRM_STATE_ERROR ?
2402 -EINVAL : -EAGAIN);
2403 xfrm_state_put(x);
2404 } else if (error == -ESRCH) {
2405 error = -EAGAIN;
2406 }
2407
2408 if (!tmpl->optional)
2409 goto fail;
2410 }
2411 return nx;
2412
2413 fail:
2414 for (nx--; nx >= 0; nx--)
2415 xfrm_state_put(xfrm[nx]);
2416 return error;
2417 }
2418
2419 static int
2420 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2421 struct xfrm_state **xfrm, unsigned short family)
2422 {
2423 struct xfrm_state *tp[XFRM_MAX_DEPTH];
2424 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2425 int cnx = 0;
2426 int error;
2427 int ret;
2428 int i;
2429
2430 for (i = 0; i < npols; i++) {
2431 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2432 error = -ENOBUFS;
2433 goto fail;
2434 }
2435
2436 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2437 if (ret < 0) {
2438 error = ret;
2439 goto fail;
2440 } else
2441 cnx += ret;
2442 }
2443
2444 /* found states are sorted for outbound processing */
2445 if (npols > 1)
2446 xfrm_state_sort(xfrm, tpp, cnx, family);
2447
2448 return cnx;
2449
2450 fail:
2451 for (cnx--; cnx >= 0; cnx--)
2452 xfrm_state_put(tpp[cnx]);
2453 return error;
2454
2455 }
2456
2457 static int xfrm_get_tos(const struct flowi *fl, int family)
2458 {
2459 if (family == AF_INET)
2460 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2461
2462 return 0;
2463 }
2464
2465 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2466 {
2467 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2468 struct dst_ops *dst_ops;
2469 struct xfrm_dst *xdst;
2470
2471 if (!afinfo)
2472 return ERR_PTR(-EINVAL);
2473
2474 switch (family) {
2475 case AF_INET:
2476 dst_ops = &net->xfrm.xfrm4_dst_ops;
2477 break;
2478 #if IS_ENABLED(CONFIG_IPV6)
2479 case AF_INET6:
2480 dst_ops = &net->xfrm.xfrm6_dst_ops;
2481 break;
2482 #endif
2483 default:
2484 BUG();
2485 }
2486 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2487
2488 if (likely(xdst)) {
2489 struct dst_entry *dst = &xdst->u.dst;
2490
2491 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
2492 } else
2493 xdst = ERR_PTR(-ENOBUFS);
2494
2495 rcu_read_unlock();
2496
2497 return xdst;
2498 }
2499
2500 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2501 int nfheader_len)
2502 {
2503 if (dst->ops->family == AF_INET6) {
2504 struct rt6_info *rt = (struct rt6_info *)dst;
2505 path->path_cookie = rt6_get_cookie(rt);
2506 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2507 }
2508 }
2509
2510 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2511 const struct flowi *fl)
2512 {
2513 const struct xfrm_policy_afinfo *afinfo =
2514 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2515 int err;
2516
2517 if (!afinfo)
2518 return -EINVAL;
2519
2520 err = afinfo->fill_dst(xdst, dev, fl);
2521
2522 rcu_read_unlock();
2523
2524 return err;
2525 }
2526
2527
2528 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2529 * all the metrics... Shortly, bundle a bundle.
2530 */
2531
2532 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2533 struct xfrm_state **xfrm,
2534 struct xfrm_dst **bundle,
2535 int nx,
2536 const struct flowi *fl,
2537 struct dst_entry *dst)
2538 {
2539 const struct xfrm_state_afinfo *afinfo;
2540 const struct xfrm_mode *inner_mode;
2541 struct net *net = xp_net(policy);
2542 unsigned long now = jiffies;
2543 struct net_device *dev;
2544 struct xfrm_dst *xdst_prev = NULL;
2545 struct xfrm_dst *xdst0 = NULL;
2546 int i = 0;
2547 int err;
2548 int header_len = 0;
2549 int nfheader_len = 0;
2550 int trailer_len = 0;
2551 int tos;
2552 int family = policy->selector.family;
2553 xfrm_address_t saddr, daddr;
2554
2555 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2556
2557 tos = xfrm_get_tos(fl, family);
2558
2559 dst_hold(dst);
2560
2561 for (; i < nx; i++) {
2562 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2563 struct dst_entry *dst1 = &xdst->u.dst;
2564
2565 err = PTR_ERR(xdst);
2566 if (IS_ERR(xdst)) {
2567 dst_release(dst);
2568 goto put_states;
2569 }
2570
2571 bundle[i] = xdst;
2572 if (!xdst_prev)
2573 xdst0 = xdst;
2574 else
2575 /* Ref count is taken during xfrm_alloc_dst()
2576 * No need to do dst_clone() on dst1
2577 */
2578 xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2579
2580 if (xfrm[i]->sel.family == AF_UNSPEC) {
2581 inner_mode = xfrm_ip2inner_mode(xfrm[i],
2582 xfrm_af2proto(family));
2583 if (!inner_mode) {
2584 err = -EAFNOSUPPORT;
2585 dst_release(dst);
2586 goto put_states;
2587 }
2588 } else
2589 inner_mode = &xfrm[i]->inner_mode;
2590
2591 xdst->route = dst;
2592 dst_copy_metrics(dst1, dst);
2593
2594 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2595 __u32 mark = 0;
2596
2597 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2598 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2599
2600 family = xfrm[i]->props.family;
2601 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
2602 &saddr, &daddr, family, mark);
2603 err = PTR_ERR(dst);
2604 if (IS_ERR(dst))
2605 goto put_states;
2606 } else
2607 dst_hold(dst);
2608
2609 dst1->xfrm = xfrm[i];
2610 xdst->xfrm_genid = xfrm[i]->genid;
2611
2612 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2613 dst1->lastuse = now;
2614
2615 dst1->input = dst_discard;
2616
2617 rcu_read_lock();
2618 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2619 if (likely(afinfo))
2620 dst1->output = afinfo->output;
2621 else
2622 dst1->output = dst_discard_out;
2623 rcu_read_unlock();
2624
2625 xdst_prev = xdst;
2626
2627 header_len += xfrm[i]->props.header_len;
2628 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2629 nfheader_len += xfrm[i]->props.header_len;
2630 trailer_len += xfrm[i]->props.trailer_len;
2631 }
2632
2633 xfrm_dst_set_child(xdst_prev, dst);
2634 xdst0->path = dst;
2635
2636 err = -ENODEV;
2637 dev = dst->dev;
2638 if (!dev)
2639 goto free_dst;
2640
2641 xfrm_init_path(xdst0, dst, nfheader_len);
2642 xfrm_init_pmtu(bundle, nx);
2643
2644 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2645 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2646 err = xfrm_fill_dst(xdst_prev, dev, fl);
2647 if (err)
2648 goto free_dst;
2649
2650 xdst_prev->u.dst.header_len = header_len;
2651 xdst_prev->u.dst.trailer_len = trailer_len;
2652 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2653 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2654 }
2655
2656 return &xdst0->u.dst;
2657
2658 put_states:
2659 for (; i < nx; i++)
2660 xfrm_state_put(xfrm[i]);
2661 free_dst:
2662 if (xdst0)
2663 dst_release_immediate(&xdst0->u.dst);
2664
2665 return ERR_PTR(err);
2666 }
2667
2668 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2669 struct xfrm_policy **pols,
2670 int *num_pols, int *num_xfrms)
2671 {
2672 int i;
2673
2674 if (*num_pols == 0 || !pols[0]) {
2675 *num_pols = 0;
2676 *num_xfrms = 0;
2677 return 0;
2678 }
2679 if (IS_ERR(pols[0]))
2680 return PTR_ERR(pols[0]);
2681
2682 *num_xfrms = pols[0]->xfrm_nr;
2683
2684 #ifdef CONFIG_XFRM_SUB_POLICY
2685 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
2686 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2687 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2688 XFRM_POLICY_TYPE_MAIN,
2689 fl, family,
2690 XFRM_POLICY_OUT,
2691 pols[0]->if_id);
2692 if (pols[1]) {
2693 if (IS_ERR(pols[1])) {
2694 xfrm_pols_put(pols, *num_pols);
2695 return PTR_ERR(pols[1]);
2696 }
2697 (*num_pols)++;
2698 (*num_xfrms) += pols[1]->xfrm_nr;
2699 }
2700 }
2701 #endif
2702 for (i = 0; i < *num_pols; i++) {
2703 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2704 *num_xfrms = -1;
2705 break;
2706 }
2707 }
2708
2709 return 0;
2710
2711 }
2712
2713 static struct xfrm_dst *
2714 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2715 const struct flowi *fl, u16 family,
2716 struct dst_entry *dst_orig)
2717 {
2718 struct net *net = xp_net(pols[0]);
2719 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2720 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2721 struct xfrm_dst *xdst;
2722 struct dst_entry *dst;
2723 int err;
2724
2725 /* Try to instantiate a bundle */
2726 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2727 if (err <= 0) {
2728 if (err == 0)
2729 return NULL;
2730
2731 if (err != -EAGAIN)
2732 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2733 return ERR_PTR(err);
2734 }
2735
2736 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2737 if (IS_ERR(dst)) {
2738 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2739 return ERR_CAST(dst);
2740 }
2741
2742 xdst = (struct xfrm_dst *)dst;
2743 xdst->num_xfrms = err;
2744 xdst->num_pols = num_pols;
2745 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2746 xdst->policy_genid = atomic_read(&pols[0]->genid);
2747
2748 return xdst;
2749 }
2750
2751 static void xfrm_policy_queue_process(struct timer_list *t)
2752 {
2753 struct sk_buff *skb;
2754 struct sock *sk;
2755 struct dst_entry *dst;
2756 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2757 struct net *net = xp_net(pol);
2758 struct xfrm_policy_queue *pq = &pol->polq;
2759 struct flowi fl;
2760 struct sk_buff_head list;
2761
2762 spin_lock(&pq->hold_queue.lock);
2763 skb = skb_peek(&pq->hold_queue);
2764 if (!skb) {
2765 spin_unlock(&pq->hold_queue.lock);
2766 goto out;
2767 }
2768 dst = skb_dst(skb);
2769 sk = skb->sk;
2770 xfrm_decode_session(skb, &fl, dst->ops->family);
2771 spin_unlock(&pq->hold_queue.lock);
2772
2773 dst_hold(xfrm_dst_path(dst));
2774 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2775 if (IS_ERR(dst))
2776 goto purge_queue;
2777
2778 if (dst->flags & DST_XFRM_QUEUE) {
2779 dst_release(dst);
2780
2781 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2782 goto purge_queue;
2783
2784 pq->timeout = pq->timeout << 1;
2785 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2786 xfrm_pol_hold(pol);
2787 goto out;
2788 }
2789
2790 dst_release(dst);
2791
2792 __skb_queue_head_init(&list);
2793
2794 spin_lock(&pq->hold_queue.lock);
2795 pq->timeout = 0;
2796 skb_queue_splice_init(&pq->hold_queue, &list);
2797 spin_unlock(&pq->hold_queue.lock);
2798
2799 while (!skb_queue_empty(&list)) {
2800 skb = __skb_dequeue(&list);
2801
2802 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2803 dst_hold(xfrm_dst_path(skb_dst(skb)));
2804 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2805 if (IS_ERR(dst)) {
2806 kfree_skb(skb);
2807 continue;
2808 }
2809
2810 nf_reset_ct(skb);
2811 skb_dst_drop(skb);
2812 skb_dst_set(skb, dst);
2813
2814 dst_output(net, skb->sk, skb);
2815 }
2816
2817 out:
2818 xfrm_pol_put(pol);
2819 return;
2820
2821 purge_queue:
2822 pq->timeout = 0;
2823 skb_queue_purge(&pq->hold_queue);
2824 xfrm_pol_put(pol);
2825 }
2826
2827 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2828 {
2829 unsigned long sched_next;
2830 struct dst_entry *dst = skb_dst(skb);
2831 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2832 struct xfrm_policy *pol = xdst->pols[0];
2833 struct xfrm_policy_queue *pq = &pol->polq;
2834
2835 if (unlikely(skb_fclone_busy(sk, skb))) {
2836 kfree_skb(skb);
2837 return 0;
2838 }
2839
2840 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2841 kfree_skb(skb);
2842 return -EAGAIN;
2843 }
2844
2845 skb_dst_force(skb);
2846
2847 spin_lock_bh(&pq->hold_queue.lock);
2848
2849 if (!pq->timeout)
2850 pq->timeout = XFRM_QUEUE_TMO_MIN;
2851
2852 sched_next = jiffies + pq->timeout;
2853
2854 if (del_timer(&pq->hold_timer)) {
2855 if (time_before(pq->hold_timer.expires, sched_next))
2856 sched_next = pq->hold_timer.expires;
2857 xfrm_pol_put(pol);
2858 }
2859
2860 __skb_queue_tail(&pq->hold_queue, skb);
2861 if (!mod_timer(&pq->hold_timer, sched_next))
2862 xfrm_pol_hold(pol);
2863
2864 spin_unlock_bh(&pq->hold_queue.lock);
2865
2866 return 0;
2867 }
2868
2869 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2870 struct xfrm_flo *xflo,
2871 const struct flowi *fl,
2872 int num_xfrms,
2873 u16 family)
2874 {
2875 int err;
2876 struct net_device *dev;
2877 struct dst_entry *dst;
2878 struct dst_entry *dst1;
2879 struct xfrm_dst *xdst;
2880
2881 xdst = xfrm_alloc_dst(net, family);
2882 if (IS_ERR(xdst))
2883 return xdst;
2884
2885 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2886 net->xfrm.sysctl_larval_drop ||
2887 num_xfrms <= 0)
2888 return xdst;
2889
2890 dst = xflo->dst_orig;
2891 dst1 = &xdst->u.dst;
2892 dst_hold(dst);
2893 xdst->route = dst;
2894
2895 dst_copy_metrics(dst1, dst);
2896
2897 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2898 dst1->flags |= DST_XFRM_QUEUE;
2899 dst1->lastuse = jiffies;
2900
2901 dst1->input = dst_discard;
2902 dst1->output = xdst_queue_output;
2903
2904 dst_hold(dst);
2905 xfrm_dst_set_child(xdst, dst);
2906 xdst->path = dst;
2907
2908 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2909
2910 err = -ENODEV;
2911 dev = dst->dev;
2912 if (!dev)
2913 goto free_dst;
2914
2915 err = xfrm_fill_dst(xdst, dev, fl);
2916 if (err)
2917 goto free_dst;
2918
2919 out:
2920 return xdst;
2921
2922 free_dst:
2923 dst_release(dst1);
2924 xdst = ERR_PTR(err);
2925 goto out;
2926 }
2927
2928 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
2929 const struct flowi *fl,
2930 u16 family, u8 dir,
2931 struct xfrm_flo *xflo, u32 if_id)
2932 {
2933 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2934 int num_pols = 0, num_xfrms = 0, err;
2935 struct xfrm_dst *xdst;
2936
2937 /* Resolve policies to use if we couldn't get them from
2938 * previous cache entry */
2939 num_pols = 1;
2940 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
2941 err = xfrm_expand_policies(fl, family, pols,
2942 &num_pols, &num_xfrms);
2943 if (err < 0)
2944 goto inc_error;
2945 if (num_pols == 0)
2946 return NULL;
2947 if (num_xfrms <= 0)
2948 goto make_dummy_bundle;
2949
2950 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2951 xflo->dst_orig);
2952 if (IS_ERR(xdst)) {
2953 err = PTR_ERR(xdst);
2954 if (err == -EREMOTE) {
2955 xfrm_pols_put(pols, num_pols);
2956 return NULL;
2957 }
2958
2959 if (err != -EAGAIN)
2960 goto error;
2961 goto make_dummy_bundle;
2962 } else if (xdst == NULL) {
2963 num_xfrms = 0;
2964 goto make_dummy_bundle;
2965 }
2966
2967 return xdst;
2968
2969 make_dummy_bundle:
2970 /* We found policies, but there's no bundles to instantiate:
2971 * either because the policy blocks, has no transformations or
2972 * we could not build template (no xfrm_states).*/
2973 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2974 if (IS_ERR(xdst)) {
2975 xfrm_pols_put(pols, num_pols);
2976 return ERR_CAST(xdst);
2977 }
2978 xdst->num_pols = num_pols;
2979 xdst->num_xfrms = num_xfrms;
2980 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2981
2982 return xdst;
2983
2984 inc_error:
2985 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2986 error:
2987 xfrm_pols_put(pols, num_pols);
2988 return ERR_PTR(err);
2989 }
2990
2991 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2992 struct dst_entry *dst_orig)
2993 {
2994 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2995 struct dst_entry *ret;
2996
2997 if (!afinfo) {
2998 dst_release(dst_orig);
2999 return ERR_PTR(-EINVAL);
3000 } else {
3001 ret = afinfo->blackhole_route(net, dst_orig);
3002 }
3003 rcu_read_unlock();
3004
3005 return ret;
3006 }
3007
3008 /* Finds/creates a bundle for given flow and if_id
3009 *
3010 * At the moment we eat a raw IP route. Mostly to speed up lookups
3011 * on interfaces with disabled IPsec.
3012 *
3013 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3014 * compatibility
3015 */
3016 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3017 struct dst_entry *dst_orig,
3018 const struct flowi *fl,
3019 const struct sock *sk,
3020 int flags, u32 if_id)
3021 {
3022 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3023 struct xfrm_dst *xdst;
3024 struct dst_entry *dst, *route;
3025 u16 family = dst_orig->ops->family;
3026 u8 dir = XFRM_POLICY_OUT;
3027 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3028
3029 dst = NULL;
3030 xdst = NULL;
3031 route = NULL;
3032
3033 sk = sk_const_to_full_sk(sk);
3034 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3035 num_pols = 1;
3036 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3037 if_id);
3038 err = xfrm_expand_policies(fl, family, pols,
3039 &num_pols, &num_xfrms);
3040 if (err < 0)
3041 goto dropdst;
3042
3043 if (num_pols) {
3044 if (num_xfrms <= 0) {
3045 drop_pols = num_pols;
3046 goto no_transform;
3047 }
3048
3049 xdst = xfrm_resolve_and_create_bundle(
3050 pols, num_pols, fl,
3051 family, dst_orig);
3052
3053 if (IS_ERR(xdst)) {
3054 xfrm_pols_put(pols, num_pols);
3055 err = PTR_ERR(xdst);
3056 if (err == -EREMOTE)
3057 goto nopol;
3058
3059 goto dropdst;
3060 } else if (xdst == NULL) {
3061 num_xfrms = 0;
3062 drop_pols = num_pols;
3063 goto no_transform;
3064 }
3065
3066 route = xdst->route;
3067 }
3068 }
3069
3070 if (xdst == NULL) {
3071 struct xfrm_flo xflo;
3072
3073 xflo.dst_orig = dst_orig;
3074 xflo.flags = flags;
3075
3076 /* To accelerate a bit... */
3077 if ((dst_orig->flags & DST_NOXFRM) ||
3078 !net->xfrm.policy_count[XFRM_POLICY_OUT])
3079 goto nopol;
3080
3081 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3082 if (xdst == NULL)
3083 goto nopol;
3084 if (IS_ERR(xdst)) {
3085 err = PTR_ERR(xdst);
3086 goto dropdst;
3087 }
3088
3089 num_pols = xdst->num_pols;
3090 num_xfrms = xdst->num_xfrms;
3091 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3092 route = xdst->route;
3093 }
3094
3095 dst = &xdst->u.dst;
3096 if (route == NULL && num_xfrms > 0) {
3097 /* The only case when xfrm_bundle_lookup() returns a
3098 * bundle with null route, is when the template could
3099 * not be resolved. It means policies are there, but
3100 * bundle could not be created, since we don't yet
3101 * have the xfrm_state's. We need to wait for KM to
3102 * negotiate new SA's or bail out with error.*/
3103 if (net->xfrm.sysctl_larval_drop) {
3104 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3105 err = -EREMOTE;
3106 goto error;
3107 }
3108
3109 err = -EAGAIN;
3110
3111 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3112 goto error;
3113 }
3114
3115 no_transform:
3116 if (num_pols == 0)
3117 goto nopol;
3118
3119 if ((flags & XFRM_LOOKUP_ICMP) &&
3120 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3121 err = -ENOENT;
3122 goto error;
3123 }
3124
3125 for (i = 0; i < num_pols; i++)
3126 pols[i]->curlft.use_time = ktime_get_real_seconds();
3127
3128 if (num_xfrms < 0) {
3129 /* Prohibit the flow */
3130 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3131 err = -EPERM;
3132 goto error;
3133 } else if (num_xfrms > 0) {
3134 /* Flow transformed */
3135 dst_release(dst_orig);
3136 } else {
3137 /* Flow passes untransformed */
3138 dst_release(dst);
3139 dst = dst_orig;
3140 }
3141 ok:
3142 xfrm_pols_put(pols, drop_pols);
3143 if (dst && dst->xfrm &&
3144 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3145 dst->flags |= DST_XFRM_TUNNEL;
3146 return dst;
3147
3148 nopol:
3149 if (!(flags & XFRM_LOOKUP_ICMP)) {
3150 dst = dst_orig;
3151 goto ok;
3152 }
3153 err = -ENOENT;
3154 error:
3155 dst_release(dst);
3156 dropdst:
3157 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3158 dst_release(dst_orig);
3159 xfrm_pols_put(pols, drop_pols);
3160 return ERR_PTR(err);
3161 }
3162 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3163
3164 /* Main function: finds/creates a bundle for given flow.
3165 *
3166 * At the moment we eat a raw IP route. Mostly to speed up lookups
3167 * on interfaces with disabled IPsec.
3168 */
3169 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3170 const struct flowi *fl, const struct sock *sk,
3171 int flags)
3172 {
3173 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3174 }
3175 EXPORT_SYMBOL(xfrm_lookup);
3176
3177 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3178 * Otherwise we may send out blackholed packets.
3179 */
3180 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3181 const struct flowi *fl,
3182 const struct sock *sk, int flags)
3183 {
3184 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3185 flags | XFRM_LOOKUP_QUEUE |
3186 XFRM_LOOKUP_KEEP_DST_REF);
3187
3188 if (PTR_ERR(dst) == -EREMOTE)
3189 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3190
3191 if (IS_ERR(dst))
3192 dst_release(dst_orig);
3193
3194 return dst;
3195 }
3196 EXPORT_SYMBOL(xfrm_lookup_route);
3197
3198 static inline int
3199 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3200 {
3201 struct sec_path *sp = skb_sec_path(skb);
3202 struct xfrm_state *x;
3203
3204 if (!sp || idx < 0 || idx >= sp->len)
3205 return 0;
3206 x = sp->xvec[idx];
3207 if (!x->type->reject)
3208 return 0;
3209 return x->type->reject(x, skb, fl);
3210 }
3211
3212 /* When skb is transformed back to its "native" form, we have to
3213 * check policy restrictions. At the moment we make this in maximally
3214 * stupid way. Shame on me. :-) Of course, connected sockets must
3215 * have policy cached at them.
3216 */
3217
3218 static inline int
3219 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3220 unsigned short family)
3221 {
3222 if (xfrm_state_kern(x))
3223 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3224 return x->id.proto == tmpl->id.proto &&
3225 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3226 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3227 x->props.mode == tmpl->mode &&
3228 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3229 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3230 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3231 xfrm_state_addr_cmp(tmpl, x, family));
3232 }
3233
3234 /*
3235 * 0 or more than 0 is returned when validation is succeeded (either bypass
3236 * because of optional transport mode, or next index of the mathced secpath
3237 * state with the template.
3238 * -1 is returned when no matching template is found.
3239 * Otherwise "-2 - errored_index" is returned.
3240 */
3241 static inline int
3242 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3243 unsigned short family)
3244 {
3245 int idx = start;
3246
3247 if (tmpl->optional) {
3248 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3249 return start;
3250 } else
3251 start = -1;
3252 for (; idx < sp->len; idx++) {
3253 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
3254 return ++idx;
3255 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3256 if (start == -1)
3257 start = -2-idx;
3258 break;
3259 }
3260 }
3261 return start;
3262 }
3263
3264 static void
3265 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3266 {
3267 const struct iphdr *iph = ip_hdr(skb);
3268 int ihl = iph->ihl;
3269 u8 *xprth = skb_network_header(skb) + ihl * 4;
3270 struct flowi4 *fl4 = &fl->u.ip4;
3271 int oif = 0;
3272
3273 if (skb_dst(skb) && skb_dst(skb)->dev)
3274 oif = skb_dst(skb)->dev->ifindex;
3275
3276 memset(fl4, 0, sizeof(struct flowi4));
3277 fl4->flowi4_mark = skb->mark;
3278 fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3279
3280 fl4->flowi4_proto = iph->protocol;
3281 fl4->daddr = reverse ? iph->saddr : iph->daddr;
3282 fl4->saddr = reverse ? iph->daddr : iph->saddr;
3283 fl4->flowi4_tos = iph->tos;
3284
3285 if (!ip_is_fragment(iph)) {
3286 switch (iph->protocol) {
3287 case IPPROTO_UDP:
3288 case IPPROTO_UDPLITE:
3289 case IPPROTO_TCP:
3290 case IPPROTO_SCTP:
3291 case IPPROTO_DCCP:
3292 if (xprth + 4 < skb->data ||
3293 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3294 __be16 *ports;
3295
3296 xprth = skb_network_header(skb) + ihl * 4;
3297 ports = (__be16 *)xprth;
3298
3299 fl4->fl4_sport = ports[!!reverse];
3300 fl4->fl4_dport = ports[!reverse];
3301 }
3302 break;
3303 case IPPROTO_ICMP:
3304 if (xprth + 2 < skb->data ||
3305 pskb_may_pull(skb, xprth + 2 - skb->data)) {
3306 u8 *icmp;
3307
3308 xprth = skb_network_header(skb) + ihl * 4;
3309 icmp = xprth;
3310
3311 fl4->fl4_icmp_type = icmp[0];
3312 fl4->fl4_icmp_code = icmp[1];
3313 }
3314 break;
3315 case IPPROTO_ESP:
3316 if (xprth + 4 < skb->data ||
3317 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3318 __be32 *ehdr;
3319
3320 xprth = skb_network_header(skb) + ihl * 4;
3321 ehdr = (__be32 *)xprth;
3322
3323 fl4->fl4_ipsec_spi = ehdr[0];
3324 }
3325 break;
3326 case IPPROTO_AH:
3327 if (xprth + 8 < skb->data ||
3328 pskb_may_pull(skb, xprth + 8 - skb->data)) {
3329 __be32 *ah_hdr;
3330
3331 xprth = skb_network_header(skb) + ihl * 4;
3332 ah_hdr = (__be32 *)xprth;
3333
3334 fl4->fl4_ipsec_spi = ah_hdr[1];
3335 }
3336 break;
3337 case IPPROTO_COMP:
3338 if (xprth + 4 < skb->data ||
3339 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3340 __be16 *ipcomp_hdr;
3341
3342 xprth = skb_network_header(skb) + ihl * 4;
3343 ipcomp_hdr = (__be16 *)xprth;
3344
3345 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
3346 }
3347 break;
3348 case IPPROTO_GRE:
3349 if (xprth + 12 < skb->data ||
3350 pskb_may_pull(skb, xprth + 12 - skb->data)) {
3351 __be16 *greflags;
3352 __be32 *gre_hdr;
3353
3354 xprth = skb_network_header(skb) + ihl * 4;
3355 greflags = (__be16 *)xprth;
3356 gre_hdr = (__be32 *)xprth;
3357
3358 if (greflags[0] & GRE_KEY) {
3359 if (greflags[0] & GRE_CSUM)
3360 gre_hdr++;
3361 fl4->fl4_gre_key = gre_hdr[1];
3362 }
3363 }
3364 break;
3365 default:
3366 fl4->fl4_ipsec_spi = 0;
3367 break;
3368 }
3369 }
3370 }
3371
3372 #if IS_ENABLED(CONFIG_IPV6)
3373 static void
3374 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3375 {
3376 struct flowi6 *fl6 = &fl->u.ip6;
3377 int onlyproto = 0;
3378 const struct ipv6hdr *hdr = ipv6_hdr(skb);
3379 u32 offset = sizeof(*hdr);
3380 struct ipv6_opt_hdr *exthdr;
3381 const unsigned char *nh = skb_network_header(skb);
3382 u16 nhoff = IP6CB(skb)->nhoff;
3383 int oif = 0;
3384 u8 nexthdr;
3385
3386 if (!nhoff)
3387 nhoff = offsetof(struct ipv6hdr, nexthdr);
3388
3389 nexthdr = nh[nhoff];
3390
3391 if (skb_dst(skb) && skb_dst(skb)->dev)
3392 oif = skb_dst(skb)->dev->ifindex;
3393
3394 memset(fl6, 0, sizeof(struct flowi6));
3395 fl6->flowi6_mark = skb->mark;
3396 fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3397
3398 fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3399 fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3400
3401 while (nh + offset + sizeof(*exthdr) < skb->data ||
3402 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3403 nh = skb_network_header(skb);
3404 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3405
3406 switch (nexthdr) {
3407 case NEXTHDR_FRAGMENT:
3408 onlyproto = 1;
3409 /* fall through */
3410 case NEXTHDR_ROUTING:
3411 case NEXTHDR_HOP:
3412 case NEXTHDR_DEST:
3413 offset += ipv6_optlen(exthdr);
3414 nexthdr = exthdr->nexthdr;
3415 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3416 break;
3417 case IPPROTO_UDP:
3418 case IPPROTO_UDPLITE:
3419 case IPPROTO_TCP:
3420 case IPPROTO_SCTP:
3421 case IPPROTO_DCCP:
3422 if (!onlyproto && (nh + offset + 4 < skb->data ||
3423 pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3424 __be16 *ports;
3425
3426 nh = skb_network_header(skb);
3427 ports = (__be16 *)(nh + offset);
3428 fl6->fl6_sport = ports[!!reverse];
3429 fl6->fl6_dport = ports[!reverse];
3430 }
3431 fl6->flowi6_proto = nexthdr;
3432 return;
3433 case IPPROTO_ICMPV6:
3434 if (!onlyproto && (nh + offset + 2 < skb->data ||
3435 pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3436 u8 *icmp;
3437
3438 nh = skb_network_header(skb);
3439 icmp = (u8 *)(nh + offset);
3440 fl6->fl6_icmp_type = icmp[0];
3441 fl6->fl6_icmp_code = icmp[1];
3442 }
3443 fl6->flowi6_proto = nexthdr;
3444 return;
3445 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3446 case IPPROTO_MH:
3447 offset += ipv6_optlen(exthdr);
3448 if (!onlyproto && (nh + offset + 3 < skb->data ||
3449 pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3450 struct ip6_mh *mh;
3451
3452 nh = skb_network_header(skb);
3453 mh = (struct ip6_mh *)(nh + offset);
3454 fl6->fl6_mh_type = mh->ip6mh_type;
3455 }
3456 fl6->flowi6_proto = nexthdr;
3457 return;
3458 #endif
3459 /* XXX Why are there these headers? */
3460 case IPPROTO_AH:
3461 case IPPROTO_ESP:
3462 case IPPROTO_COMP:
3463 default:
3464 fl6->fl6_ipsec_spi = 0;
3465 fl6->flowi6_proto = nexthdr;
3466 return;
3467 }
3468 }
3469 }
3470 #endif
3471
3472 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3473 unsigned int family, int reverse)
3474 {
3475 switch (family) {
3476 case AF_INET:
3477 decode_session4(skb, fl, reverse);
3478 break;
3479 #if IS_ENABLED(CONFIG_IPV6)
3480 case AF_INET6:
3481 decode_session6(skb, fl, reverse);
3482 break;
3483 #endif
3484 default:
3485 return -EAFNOSUPPORT;
3486 }
3487
3488 return security_xfrm_decode_session(skb, &fl->flowi_secid);
3489 }
3490 EXPORT_SYMBOL(__xfrm_decode_session);
3491
3492 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3493 {
3494 for (; k < sp->len; k++) {
3495 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3496 *idxp = k;
3497 return 1;
3498 }
3499 }
3500
3501 return 0;
3502 }
3503
3504 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3505 unsigned short family)
3506 {
3507 struct net *net = dev_net(skb->dev);
3508 struct xfrm_policy *pol;
3509 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3510 int npols = 0;
3511 int xfrm_nr;
3512 int pi;
3513 int reverse;
3514 struct flowi fl;
3515 int xerr_idx = -1;
3516 const struct xfrm_if_cb *ifcb;
3517 struct sec_path *sp;
3518 struct xfrm_if *xi;
3519 u32 if_id = 0;
3520
3521 rcu_read_lock();
3522 ifcb = xfrm_if_get_cb();
3523
3524 if (ifcb) {
3525 xi = ifcb->decode_session(skb, family);
3526 if (xi) {
3527 if_id = xi->p.if_id;
3528 net = xi->net;
3529 }
3530 }
3531 rcu_read_unlock();
3532
3533 reverse = dir & ~XFRM_POLICY_MASK;
3534 dir &= XFRM_POLICY_MASK;
3535
3536 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3537 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3538 return 0;
3539 }
3540
3541 nf_nat_decode_session(skb, &fl, family);
3542
3543 /* First, check used SA against their selectors. */
3544 sp = skb_sec_path(skb);
3545 if (sp) {
3546 int i;
3547
3548 for (i = sp->len - 1; i >= 0; i--) {
3549 struct xfrm_state *x = sp->xvec[i];
3550 if (!xfrm_selector_match(&x->sel, &fl, family)) {
3551 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3552 return 0;
3553 }
3554 }
3555 }
3556
3557 pol = NULL;
3558 sk = sk_to_full_sk(sk);
3559 if (sk && sk->sk_policy[dir]) {
3560 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3561 if (IS_ERR(pol)) {
3562 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3563 return 0;
3564 }
3565 }
3566
3567 if (!pol)
3568 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3569
3570 if (IS_ERR(pol)) {
3571 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3572 return 0;
3573 }
3574
3575 if (!pol) {
3576 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3577 xfrm_secpath_reject(xerr_idx, skb, &fl);
3578 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3579 return 0;
3580 }
3581 return 1;
3582 }
3583
3584 pol->curlft.use_time = ktime_get_real_seconds();
3585
3586 pols[0] = pol;
3587 npols++;
3588 #ifdef CONFIG_XFRM_SUB_POLICY
3589 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3590 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3591 &fl, family,
3592 XFRM_POLICY_IN, if_id);
3593 if (pols[1]) {
3594 if (IS_ERR(pols[1])) {
3595 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3596 return 0;
3597 }
3598 pols[1]->curlft.use_time = ktime_get_real_seconds();
3599 npols++;
3600 }
3601 }
3602 #endif
3603
3604 if (pol->action == XFRM_POLICY_ALLOW) {
3605 static struct sec_path dummy;
3606 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3607 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3608 struct xfrm_tmpl **tpp = tp;
3609 int ti = 0;
3610 int i, k;
3611
3612 sp = skb_sec_path(skb);
3613 if (!sp)
3614 sp = &dummy;
3615
3616 for (pi = 0; pi < npols; pi++) {
3617 if (pols[pi] != pol &&
3618 pols[pi]->action != XFRM_POLICY_ALLOW) {
3619 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3620 goto reject;
3621 }
3622 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3623 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3624 goto reject_error;
3625 }
3626 for (i = 0; i < pols[pi]->xfrm_nr; i++)
3627 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3628 }
3629 xfrm_nr = ti;
3630 if (npols > 1) {
3631 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3632 tpp = stp;
3633 }
3634
3635 /* For each tunnel xfrm, find the first matching tmpl.
3636 * For each tmpl before that, find corresponding xfrm.
3637 * Order is _important_. Later we will implement
3638 * some barriers, but at the moment barriers
3639 * are implied between each two transformations.
3640 */
3641 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3642 k = xfrm_policy_ok(tpp[i], sp, k, family);
3643 if (k < 0) {
3644 if (k < -1)
3645 /* "-2 - errored_index" returned */
3646 xerr_idx = -(2+k);
3647 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3648 goto reject;
3649 }
3650 }
3651
3652 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3653 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3654 goto reject;
3655 }
3656
3657 xfrm_pols_put(pols, npols);
3658 return 1;
3659 }
3660 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3661
3662 reject:
3663 xfrm_secpath_reject(xerr_idx, skb, &fl);
3664 reject_error:
3665 xfrm_pols_put(pols, npols);
3666 return 0;
3667 }
3668 EXPORT_SYMBOL(__xfrm_policy_check);
3669
3670 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3671 {
3672 struct net *net = dev_net(skb->dev);
3673 struct flowi fl;
3674 struct dst_entry *dst;
3675 int res = 1;
3676
3677 if (xfrm_decode_session(skb, &fl, family) < 0) {
3678 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3679 return 0;
3680 }
3681
3682 skb_dst_force(skb);
3683 if (!skb_dst(skb)) {
3684 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3685 return 0;
3686 }
3687
3688 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3689 if (IS_ERR(dst)) {
3690 res = 0;
3691 dst = NULL;
3692 }
3693 skb_dst_set(skb, dst);
3694 return res;
3695 }
3696 EXPORT_SYMBOL(__xfrm_route_forward);
3697
3698 /* Optimize later using cookies and generation ids. */
3699
3700 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3701 {
3702 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3703 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3704 * get validated by dst_ops->check on every use. We do this
3705 * because when a normal route referenced by an XFRM dst is
3706 * obsoleted we do not go looking around for all parent
3707 * referencing XFRM dsts so that we can invalidate them. It
3708 * is just too much work. Instead we make the checks here on
3709 * every use. For example:
3710 *
3711 * XFRM dst A --> IPv4 dst X
3712 *
3713 * X is the "xdst->route" of A (X is also the "dst->path" of A
3714 * in this example). If X is marked obsolete, "A" will not
3715 * notice. That's what we are validating here via the
3716 * stale_bundle() check.
3717 *
3718 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3719 * be marked on it.
3720 * This will force stale_bundle() to fail on any xdst bundle with
3721 * this dst linked in it.
3722 */
3723 if (dst->obsolete < 0 && !stale_bundle(dst))
3724 return dst;
3725
3726 return NULL;
3727 }
3728
3729 static int stale_bundle(struct dst_entry *dst)
3730 {
3731 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3732 }
3733
3734 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3735 {
3736 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3737 dst->dev = dev_net(dev)->loopback_dev;
3738 dev_hold(dst->dev);
3739 dev_put(dev);
3740 }
3741 }
3742 EXPORT_SYMBOL(xfrm_dst_ifdown);
3743
3744 static void xfrm_link_failure(struct sk_buff *skb)
3745 {
3746 /* Impossible. Such dst must be popped before reaches point of failure. */
3747 }
3748
3749 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3750 {
3751 if (dst) {
3752 if (dst->obsolete) {
3753 dst_release(dst);
3754 dst = NULL;
3755 }
3756 }
3757 return dst;
3758 }
3759
3760 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3761 {
3762 while (nr--) {
3763 struct xfrm_dst *xdst = bundle[nr];
3764 u32 pmtu, route_mtu_cached;
3765 struct dst_entry *dst;
3766
3767 dst = &xdst->u.dst;
3768 pmtu = dst_mtu(xfrm_dst_child(dst));
3769 xdst->child_mtu_cached = pmtu;
3770
3771 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3772
3773 route_mtu_cached = dst_mtu(xdst->route);
3774 xdst->route_mtu_cached = route_mtu_cached;
3775
3776 if (pmtu > route_mtu_cached)
3777 pmtu = route_mtu_cached;
3778
3779 dst_metric_set(dst, RTAX_MTU, pmtu);
3780 }
3781 }
3782
3783 /* Check that the bundle accepts the flow and its components are
3784 * still valid.
3785 */
3786
3787 static int xfrm_bundle_ok(struct xfrm_dst *first)
3788 {
3789 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3790 struct dst_entry *dst = &first->u.dst;
3791 struct xfrm_dst *xdst;
3792 int start_from, nr;
3793 u32 mtu;
3794
3795 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3796 (dst->dev && !netif_running(dst->dev)))
3797 return 0;
3798
3799 if (dst->flags & DST_XFRM_QUEUE)
3800 return 1;
3801
3802 start_from = nr = 0;
3803 do {
3804 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3805
3806 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3807 return 0;
3808 if (xdst->xfrm_genid != dst->xfrm->genid)
3809 return 0;
3810 if (xdst->num_pols > 0 &&
3811 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3812 return 0;
3813
3814 bundle[nr++] = xdst;
3815
3816 mtu = dst_mtu(xfrm_dst_child(dst));
3817 if (xdst->child_mtu_cached != mtu) {
3818 start_from = nr;
3819 xdst->child_mtu_cached = mtu;
3820 }
3821
3822 if (!dst_check(xdst->route, xdst->route_cookie))
3823 return 0;
3824 mtu = dst_mtu(xdst->route);
3825 if (xdst->route_mtu_cached != mtu) {
3826 start_from = nr;
3827 xdst->route_mtu_cached = mtu;
3828 }
3829
3830 dst = xfrm_dst_child(dst);
3831 } while (dst->xfrm);
3832
3833 if (likely(!start_from))
3834 return 1;
3835
3836 xdst = bundle[start_from - 1];
3837 mtu = xdst->child_mtu_cached;
3838 while (start_from--) {
3839 dst = &xdst->u.dst;
3840
3841 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3842 if (mtu > xdst->route_mtu_cached)
3843 mtu = xdst->route_mtu_cached;
3844 dst_metric_set(dst, RTAX_MTU, mtu);
3845 if (!start_from)
3846 break;
3847
3848 xdst = bundle[start_from - 1];
3849 xdst->child_mtu_cached = mtu;
3850 }
3851
3852 return 1;
3853 }
3854
3855 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3856 {
3857 return dst_metric_advmss(xfrm_dst_path(dst));
3858 }
3859
3860 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3861 {
3862 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3863
3864 return mtu ? : dst_mtu(xfrm_dst_path(dst));
3865 }
3866
3867 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3868 const void *daddr)
3869 {
3870 while (dst->xfrm) {
3871 const struct xfrm_state *xfrm = dst->xfrm;
3872
3873 dst = xfrm_dst_child(dst);
3874
3875 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3876 continue;
3877 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3878 daddr = xfrm->coaddr;
3879 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3880 daddr = &xfrm->id.daddr;
3881 }
3882 return daddr;
3883 }
3884
3885 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3886 struct sk_buff *skb,
3887 const void *daddr)
3888 {
3889 const struct dst_entry *path = xfrm_dst_path(dst);
3890
3891 if (!skb)
3892 daddr = xfrm_get_dst_nexthop(dst, daddr);
3893 return path->ops->neigh_lookup(path, skb, daddr);
3894 }
3895
3896 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3897 {
3898 const struct dst_entry *path = xfrm_dst_path(dst);
3899
3900 daddr = xfrm_get_dst_nexthop(dst, daddr);
3901 path->ops->confirm_neigh(path, daddr);
3902 }
3903
3904 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3905 {
3906 int err = 0;
3907
3908 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3909 return -EAFNOSUPPORT;
3910
3911 spin_lock(&xfrm_policy_afinfo_lock);
3912 if (unlikely(xfrm_policy_afinfo[family] != NULL))
3913 err = -EEXIST;
3914 else {
3915 struct dst_ops *dst_ops = afinfo->dst_ops;
3916 if (likely(dst_ops->kmem_cachep == NULL))
3917 dst_ops->kmem_cachep = xfrm_dst_cache;
3918 if (likely(dst_ops->check == NULL))
3919 dst_ops->check = xfrm_dst_check;
3920 if (likely(dst_ops->default_advmss == NULL))
3921 dst_ops->default_advmss = xfrm_default_advmss;
3922 if (likely(dst_ops->mtu == NULL))
3923 dst_ops->mtu = xfrm_mtu;
3924 if (likely(dst_ops->negative_advice == NULL))
3925 dst_ops->negative_advice = xfrm_negative_advice;
3926 if (likely(dst_ops->link_failure == NULL))
3927 dst_ops->link_failure = xfrm_link_failure;
3928 if (likely(dst_ops->neigh_lookup == NULL))
3929 dst_ops->neigh_lookup = xfrm_neigh_lookup;
3930 if (likely(!dst_ops->confirm_neigh))
3931 dst_ops->confirm_neigh = xfrm_confirm_neigh;
3932 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
3933 }
3934 spin_unlock(&xfrm_policy_afinfo_lock);
3935
3936 return err;
3937 }
3938 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
3939
3940 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
3941 {
3942 struct dst_ops *dst_ops = afinfo->dst_ops;
3943 int i;
3944
3945 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
3946 if (xfrm_policy_afinfo[i] != afinfo)
3947 continue;
3948 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
3949 break;
3950 }
3951
3952 synchronize_rcu();
3953
3954 dst_ops->kmem_cachep = NULL;
3955 dst_ops->check = NULL;
3956 dst_ops->negative_advice = NULL;
3957 dst_ops->link_failure = NULL;
3958 }
3959 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
3960
3961 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
3962 {
3963 spin_lock(&xfrm_if_cb_lock);
3964 rcu_assign_pointer(xfrm_if_cb, ifcb);
3965 spin_unlock(&xfrm_if_cb_lock);
3966 }
3967 EXPORT_SYMBOL(xfrm_if_register_cb);
3968
3969 void xfrm_if_unregister_cb(void)
3970 {
3971 RCU_INIT_POINTER(xfrm_if_cb, NULL);
3972 synchronize_rcu();
3973 }
3974 EXPORT_SYMBOL(xfrm_if_unregister_cb);
3975
3976 #ifdef CONFIG_XFRM_STATISTICS
3977 static int __net_init xfrm_statistics_init(struct net *net)
3978 {
3979 int rv;
3980 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
3981 if (!net->mib.xfrm_statistics)
3982 return -ENOMEM;
3983 rv = xfrm_proc_init(net);
3984 if (rv < 0)
3985 free_percpu(net->mib.xfrm_statistics);
3986 return rv;
3987 }
3988
3989 static void xfrm_statistics_fini(struct net *net)
3990 {
3991 xfrm_proc_fini(net);
3992 free_percpu(net->mib.xfrm_statistics);
3993 }
3994 #else
3995 static int __net_init xfrm_statistics_init(struct net *net)
3996 {
3997 return 0;
3998 }
3999
4000 static void xfrm_statistics_fini(struct net *net)
4001 {
4002 }
4003 #endif
4004
4005 static int __net_init xfrm_policy_init(struct net *net)
4006 {
4007 unsigned int hmask, sz;
4008 int dir, err;
4009
4010 if (net_eq(net, &init_net)) {
4011 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4012 sizeof(struct xfrm_dst),
4013 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4014 NULL);
4015 err = rhashtable_init(&xfrm_policy_inexact_table,
4016 &xfrm_pol_inexact_params);
4017 BUG_ON(err);
4018 }
4019
4020 hmask = 8 - 1;
4021 sz = (hmask+1) * sizeof(struct hlist_head);
4022
4023 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4024 if (!net->xfrm.policy_byidx)
4025 goto out_byidx;
4026 net->xfrm.policy_idx_hmask = hmask;
4027
4028 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4029 struct xfrm_policy_hash *htab;
4030
4031 net->xfrm.policy_count[dir] = 0;
4032 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4033 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4034
4035 htab = &net->xfrm.policy_bydst[dir];
4036 htab->table = xfrm_hash_alloc(sz);
4037 if (!htab->table)
4038 goto out_bydst;
4039 htab->hmask = hmask;
4040 htab->dbits4 = 32;
4041 htab->sbits4 = 32;
4042 htab->dbits6 = 128;
4043 htab->sbits6 = 128;
4044 }
4045 net->xfrm.policy_hthresh.lbits4 = 32;
4046 net->xfrm.policy_hthresh.rbits4 = 32;
4047 net->xfrm.policy_hthresh.lbits6 = 128;
4048 net->xfrm.policy_hthresh.rbits6 = 128;
4049
4050 seqlock_init(&net->xfrm.policy_hthresh.lock);
4051
4052 INIT_LIST_HEAD(&net->xfrm.policy_all);
4053 INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4054 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4055 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4056 return 0;
4057
4058 out_bydst:
4059 for (dir--; dir >= 0; dir--) {
4060 struct xfrm_policy_hash *htab;
4061
4062 htab = &net->xfrm.policy_bydst[dir];
4063 xfrm_hash_free(htab->table, sz);
4064 }
4065 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4066 out_byidx:
4067 return -ENOMEM;
4068 }
4069
4070 static void xfrm_policy_fini(struct net *net)
4071 {
4072 struct xfrm_pol_inexact_bin *b, *t;
4073 unsigned int sz;
4074 int dir;
4075
4076 flush_work(&net->xfrm.policy_hash_work);
4077 #ifdef CONFIG_XFRM_SUB_POLICY
4078 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4079 #endif
4080 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4081
4082 WARN_ON(!list_empty(&net->xfrm.policy_all));
4083
4084 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4085 struct xfrm_policy_hash *htab;
4086
4087 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4088
4089 htab = &net->xfrm.policy_bydst[dir];
4090 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4091 WARN_ON(!hlist_empty(htab->table));
4092 xfrm_hash_free(htab->table, sz);
4093 }
4094
4095 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4096 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4097 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4098
4099 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4100 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4101 __xfrm_policy_inexact_prune_bin(b, true);
4102 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4103 }
4104
4105 static int __net_init xfrm_net_init(struct net *net)
4106 {
4107 int rv;
4108
4109 /* Initialize the per-net locks here */
4110 spin_lock_init(&net->xfrm.xfrm_state_lock);
4111 spin_lock_init(&net->xfrm.xfrm_policy_lock);
4112 mutex_init(&net->xfrm.xfrm_cfg_mutex);
4113
4114 rv = xfrm_statistics_init(net);
4115 if (rv < 0)
4116 goto out_statistics;
4117 rv = xfrm_state_init(net);
4118 if (rv < 0)
4119 goto out_state;
4120 rv = xfrm_policy_init(net);
4121 if (rv < 0)
4122 goto out_policy;
4123 rv = xfrm_sysctl_init(net);
4124 if (rv < 0)
4125 goto out_sysctl;
4126
4127 return 0;
4128
4129 out_sysctl:
4130 xfrm_policy_fini(net);
4131 out_policy:
4132 xfrm_state_fini(net);
4133 out_state:
4134 xfrm_statistics_fini(net);
4135 out_statistics:
4136 return rv;
4137 }
4138
4139 static void __net_exit xfrm_net_exit(struct net *net)
4140 {
4141 xfrm_sysctl_fini(net);
4142 xfrm_policy_fini(net);
4143 xfrm_state_fini(net);
4144 xfrm_statistics_fini(net);
4145 }
4146
4147 static struct pernet_operations __net_initdata xfrm_net_ops = {
4148 .init = xfrm_net_init,
4149 .exit = xfrm_net_exit,
4150 };
4151
4152 void __init xfrm_init(void)
4153 {
4154 register_pernet_subsys(&xfrm_net_ops);
4155 xfrm_dev_init();
4156 seqcount_init(&xfrm_policy_hash_generation);
4157 xfrm_input_init();
4158
4159 #ifdef CONFIG_INET_ESPINTCP
4160 espintcp_init();
4161 #endif
4162
4163 RCU_INIT_POINTER(xfrm_if_cb, NULL);
4164 synchronize_rcu();
4165 }
4166
4167 #ifdef CONFIG_AUDITSYSCALL
4168 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4169 struct audit_buffer *audit_buf)
4170 {
4171 struct xfrm_sec_ctx *ctx = xp->security;
4172 struct xfrm_selector *sel = &xp->selector;
4173
4174 if (ctx)
4175 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4176 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4177
4178 switch (sel->family) {
4179 case AF_INET:
4180 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4181 if (sel->prefixlen_s != 32)
4182 audit_log_format(audit_buf, " src_prefixlen=%d",
4183 sel->prefixlen_s);
4184 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4185 if (sel->prefixlen_d != 32)
4186 audit_log_format(audit_buf, " dst_prefixlen=%d",
4187 sel->prefixlen_d);
4188 break;
4189 case AF_INET6:
4190 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4191 if (sel->prefixlen_s != 128)
4192 audit_log_format(audit_buf, " src_prefixlen=%d",
4193 sel->prefixlen_s);
4194 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4195 if (sel->prefixlen_d != 128)
4196 audit_log_format(audit_buf, " dst_prefixlen=%d",
4197 sel->prefixlen_d);
4198 break;
4199 }
4200 }
4201
4202 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4203 {
4204 struct audit_buffer *audit_buf;
4205
4206 audit_buf = xfrm_audit_start("SPD-add");
4207 if (audit_buf == NULL)
4208 return;
4209 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4210 audit_log_format(audit_buf, " res=%u", result);
4211 xfrm_audit_common_policyinfo(xp, audit_buf);
4212 audit_log_end(audit_buf);
4213 }
4214 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4215
4216 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4217 bool task_valid)
4218 {
4219 struct audit_buffer *audit_buf;
4220
4221 audit_buf = xfrm_audit_start("SPD-delete");
4222 if (audit_buf == NULL)
4223 return;
4224 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4225 audit_log_format(audit_buf, " res=%u", result);
4226 xfrm_audit_common_policyinfo(xp, audit_buf);
4227 audit_log_end(audit_buf);
4228 }
4229 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4230 #endif
4231
4232 #ifdef CONFIG_XFRM_MIGRATE
4233 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4234 const struct xfrm_selector *sel_tgt)
4235 {
4236 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4237 if (sel_tgt->family == sel_cmp->family &&
4238 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4239 sel_cmp->family) &&
4240 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4241 sel_cmp->family) &&
4242 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4243 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4244 return true;
4245 }
4246 } else {
4247 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4248 return true;
4249 }
4250 }
4251 return false;
4252 }
4253
4254 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4255 u8 dir, u8 type, struct net *net)
4256 {
4257 struct xfrm_policy *pol, *ret = NULL;
4258 struct hlist_head *chain;
4259 u32 priority = ~0U;
4260
4261 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4262 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4263 hlist_for_each_entry(pol, chain, bydst) {
4264 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4265 pol->type == type) {
4266 ret = pol;
4267 priority = ret->priority;
4268 break;
4269 }
4270 }
4271 chain = &net->xfrm.policy_inexact[dir];
4272 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4273 if ((pol->priority >= priority) && ret)
4274 break;
4275
4276 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4277 pol->type == type) {
4278 ret = pol;
4279 break;
4280 }
4281 }
4282
4283 xfrm_pol_hold(ret);
4284
4285 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4286
4287 return ret;
4288 }
4289
4290 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4291 {
4292 int match = 0;
4293
4294 if (t->mode == m->mode && t->id.proto == m->proto &&
4295 (m->reqid == 0 || t->reqid == m->reqid)) {
4296 switch (t->mode) {
4297 case XFRM_MODE_TUNNEL:
4298 case XFRM_MODE_BEET:
4299 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4300 m->old_family) &&
4301 xfrm_addr_equal(&t->saddr, &m->old_saddr,
4302 m->old_family)) {
4303 match = 1;
4304 }
4305 break;
4306 case XFRM_MODE_TRANSPORT:
4307 /* in case of transport mode, template does not store
4308 any IP addresses, hence we just compare mode and
4309 protocol */
4310 match = 1;
4311 break;
4312 default:
4313 break;
4314 }
4315 }
4316 return match;
4317 }
4318
4319 /* update endpoint address(es) of template(s) */
4320 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4321 struct xfrm_migrate *m, int num_migrate)
4322 {
4323 struct xfrm_migrate *mp;
4324 int i, j, n = 0;
4325
4326 write_lock_bh(&pol->lock);
4327 if (unlikely(pol->walk.dead)) {
4328 /* target policy has been deleted */
4329 write_unlock_bh(&pol->lock);
4330 return -ENOENT;
4331 }
4332
4333 for (i = 0; i < pol->xfrm_nr; i++) {
4334 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4335 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4336 continue;
4337 n++;
4338 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4339 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4340 continue;
4341 /* update endpoints */
4342 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4343 sizeof(pol->xfrm_vec[i].id.daddr));
4344 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4345 sizeof(pol->xfrm_vec[i].saddr));
4346 pol->xfrm_vec[i].encap_family = mp->new_family;
4347 /* flush bundles */
4348 atomic_inc(&pol->genid);
4349 }
4350 }
4351
4352 write_unlock_bh(&pol->lock);
4353
4354 if (!n)
4355 return -ENODATA;
4356
4357 return 0;
4358 }
4359
4360 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
4361 {
4362 int i, j;
4363
4364 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
4365 return -EINVAL;
4366
4367 for (i = 0; i < num_migrate; i++) {
4368 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4369 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
4370 return -EINVAL;
4371
4372 /* check if there is any duplicated entry */
4373 for (j = i + 1; j < num_migrate; j++) {
4374 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4375 sizeof(m[i].old_daddr)) &&
4376 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4377 sizeof(m[i].old_saddr)) &&
4378 m[i].proto == m[j].proto &&
4379 m[i].mode == m[j].mode &&
4380 m[i].reqid == m[j].reqid &&
4381 m[i].old_family == m[j].old_family)
4382 return -EINVAL;
4383 }
4384 }
4385
4386 return 0;
4387 }
4388
4389 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4390 struct xfrm_migrate *m, int num_migrate,
4391 struct xfrm_kmaddress *k, struct net *net,
4392 struct xfrm_encap_tmpl *encap)
4393 {
4394 int i, err, nx_cur = 0, nx_new = 0;
4395 struct xfrm_policy *pol = NULL;
4396 struct xfrm_state *x, *xc;
4397 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4398 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4399 struct xfrm_migrate *mp;
4400
4401 /* Stage 0 - sanity checks */
4402 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
4403 goto out;
4404
4405 if (dir >= XFRM_POLICY_MAX) {
4406 err = -EINVAL;
4407 goto out;
4408 }
4409
4410 /* Stage 1 - find policy */
4411 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
4412 err = -ENOENT;
4413 goto out;
4414 }
4415
4416 /* Stage 2 - find and update state(s) */
4417 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4418 if ((x = xfrm_migrate_state_find(mp, net))) {
4419 x_cur[nx_cur] = x;
4420 nx_cur++;
4421 xc = xfrm_state_migrate(x, mp, encap);
4422 if (xc) {
4423 x_new[nx_new] = xc;
4424 nx_new++;
4425 } else {
4426 err = -ENODATA;
4427 goto restore_state;
4428 }
4429 }
4430 }
4431
4432 /* Stage 3 - update policy */
4433 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
4434 goto restore_state;
4435
4436 /* Stage 4 - delete old state(s) */
4437 if (nx_cur) {
4438 xfrm_states_put(x_cur, nx_cur);
4439 xfrm_states_delete(x_cur, nx_cur);
4440 }
4441
4442 /* Stage 5 - announce */
4443 km_migrate(sel, dir, type, m, num_migrate, k, encap);
4444
4445 xfrm_pol_put(pol);
4446
4447 return 0;
4448 out:
4449 return err;
4450
4451 restore_state:
4452 if (pol)
4453 xfrm_pol_put(pol);
4454 if (nx_cur)
4455 xfrm_states_put(x_cur, nx_cur);
4456 if (nx_new)
4457 xfrm_states_delete(x_new, nx_new);
4458
4459 return err;
4460 }
4461 EXPORT_SYMBOL(xfrm_migrate);
4462 #endif
Linux with added FPC-III support