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add debugging code
[cor.git] / net / xfrm / xfrm_policy.c
blobf2d1e573ea55154eb2ee4fc3dbdd47313d969b98
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
43 #include "xfrm_hash.h"
44
45 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
46 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
47 #define XFRM_MAX_QUEUE_LEN 100
48
49 struct xfrm_flo {
50 struct dst_entry *dst_orig;
51 u8 flags;
52 };
53
54 /* prefixes smaller than this are stored in lists, not trees. */
55 #define INEXACT_PREFIXLEN_IPV4 16
56 #define INEXACT_PREFIXLEN_IPV6 48
57
58 struct xfrm_pol_inexact_node {
59 struct rb_node node;
60 union {
61 xfrm_address_t addr;
62 struct rcu_head rcu;
63 };
64 u8 prefixlen;
65
66 struct rb_root root;
67
68 /* the policies matching this node, can be empty list */
69 struct hlist_head hhead;
70 };
71
72 /* xfrm inexact policy search tree:
73 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
74 * |
75 * +---- root_d: sorted by daddr:prefix
76 * | |
77 * | xfrm_pol_inexact_node
78 * | |
79 * | +- root: sorted by saddr/prefix
80 * | | |
81 * | | xfrm_pol_inexact_node
82 * | | |
83 * | | + root: unused
84 * | | |
85 * | | + hhead: saddr:daddr policies
86 * | |
87 * | +- coarse policies and all any:daddr policies
88 * |
89 * +---- root_s: sorted by saddr:prefix
90 * | |
91 * | xfrm_pol_inexact_node
92 * | |
93 * | + root: unused
94 * | |
95 * | + hhead: saddr:any policies
96 * |
97 * +---- coarse policies and all any:any policies
98 *
99 * Lookups return four candidate lists:
100 * 1. any:any list from top-level xfrm_pol_inexact_bin
101 * 2. any:daddr list from daddr tree
102 * 3. saddr:daddr list from 2nd level daddr tree
103 * 4. saddr:any list from saddr tree
104 *
105 * This result set then needs to be searched for the policy with
106 * the lowest priority. If two results have same prio, youngest one wins.
107 */
108
109 struct xfrm_pol_inexact_key {
110 possible_net_t net;
111 u32 if_id;
112 u16 family;
113 u8 dir, type;
114 };
115
116 struct xfrm_pol_inexact_bin {
117 struct xfrm_pol_inexact_key k;
118 struct rhash_head head;
119 /* list containing '*:*' policies */
120 struct hlist_head hhead;
121
122 seqcount_t count;
123 /* tree sorted by daddr/prefix */
124 struct rb_root root_d;
125
126 /* tree sorted by saddr/prefix */
127 struct rb_root root_s;
128
129 /* slow path below */
130 struct list_head inexact_bins;
131 struct rcu_head rcu;
132 };
133
134 enum xfrm_pol_inexact_candidate_type {
135 XFRM_POL_CAND_BOTH,
136 XFRM_POL_CAND_SADDR,
137 XFRM_POL_CAND_DADDR,
138 XFRM_POL_CAND_ANY,
139
140 XFRM_POL_CAND_MAX,
141 };
142
143 struct xfrm_pol_inexact_candidates {
144 struct hlist_head *res[XFRM_POL_CAND_MAX];
145 };
146
147 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
148 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
149
150 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
151 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
152 __read_mostly;
153
154 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
155 static __read_mostly seqcount_t xfrm_policy_hash_generation;
156
157 static struct rhashtable xfrm_policy_inexact_table;
158 static const struct rhashtable_params xfrm_pol_inexact_params;
159
160 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
161 static int stale_bundle(struct dst_entry *dst);
162 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
163 static void xfrm_policy_queue_process(struct timer_list *t);
164
165 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
166 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
167 int dir);
168
169 static struct xfrm_pol_inexact_bin *
170 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
171 u32 if_id);
172
173 static struct xfrm_pol_inexact_bin *
174 xfrm_policy_inexact_lookup_rcu(struct net *net,
175 u8 type, u16 family, u8 dir, u32 if_id);
176 static struct xfrm_policy *
177 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
178 bool excl);
179 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
180 struct xfrm_policy *policy);
181
182 static bool
183 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
184 struct xfrm_pol_inexact_bin *b,
185 const xfrm_address_t *saddr,
186 const xfrm_address_t *daddr);
187
188 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
189 {
190 return refcount_inc_not_zero(&policy->refcnt);
191 }
192
193 static inline bool
194 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
195 {
196 const struct flowi4 *fl4 = &fl->u.ip4;
197
198 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
199 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
200 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
201 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
202 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
203 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
204 }
205
206 static inline bool
207 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
208 {
209 const struct flowi6 *fl6 = &fl->u.ip6;
210
211 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
212 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
213 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
214 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
215 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
216 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
217 }
218
219 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
220 unsigned short family)
221 {
222 switch (family) {
223 case AF_INET:
224 return __xfrm4_selector_match(sel, fl);
225 case AF_INET6:
226 return __xfrm6_selector_match(sel, fl);
227 }
228 return false;
229 }
230
231 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
232 {
233 const struct xfrm_policy_afinfo *afinfo;
234
235 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
236 return NULL;
237 rcu_read_lock();
238 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
239 if (unlikely(!afinfo))
240 rcu_read_unlock();
241 return afinfo;
242 }
243
244 /* Called with rcu_read_lock(). */
245 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
246 {
247 return rcu_dereference(xfrm_if_cb);
248 }
249
250 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
251 const xfrm_address_t *saddr,
252 const xfrm_address_t *daddr,
253 int family, u32 mark)
254 {
255 const struct xfrm_policy_afinfo *afinfo;
256 struct dst_entry *dst;
257
258 afinfo = xfrm_policy_get_afinfo(family);
259 if (unlikely(afinfo == NULL))
260 return ERR_PTR(-EAFNOSUPPORT);
261
262 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
263
264 rcu_read_unlock();
265
266 return dst;
267 }
268 EXPORT_SYMBOL(__xfrm_dst_lookup);
269
270 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
271 int tos, int oif,
272 xfrm_address_t *prev_saddr,
273 xfrm_address_t *prev_daddr,
274 int family, u32 mark)
275 {
276 struct net *net = xs_net(x);
277 xfrm_address_t *saddr = &x->props.saddr;
278 xfrm_address_t *daddr = &x->id.daddr;
279 struct dst_entry *dst;
280
281 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
282 saddr = x->coaddr;
283 daddr = prev_daddr;
284 }
285 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
286 saddr = prev_saddr;
287 daddr = x->coaddr;
288 }
289
290 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
291
292 if (!IS_ERR(dst)) {
293 if (prev_saddr != saddr)
294 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
295 if (prev_daddr != daddr)
296 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
297 }
298
299 return dst;
300 }
301
302 static inline unsigned long make_jiffies(long secs)
303 {
304 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
305 return MAX_SCHEDULE_TIMEOUT-1;
306 else
307 return secs*HZ;
308 }
309
310 static void xfrm_policy_timer(struct timer_list *t)
311 {
312 struct xfrm_policy *xp = from_timer(xp, t, timer);
313 time64_t now = ktime_get_real_seconds();
314 time64_t next = TIME64_MAX;
315 int warn = 0;
316 int dir;
317
318 read_lock(&xp->lock);
319
320 if (unlikely(xp->walk.dead))
321 goto out;
322
323 dir = xfrm_policy_id2dir(xp->index);
324
325 if (xp->lft.hard_add_expires_seconds) {
326 time64_t tmo = xp->lft.hard_add_expires_seconds +
327 xp->curlft.add_time - now;
328 if (tmo <= 0)
329 goto expired;
330 if (tmo < next)
331 next = tmo;
332 }
333 if (xp->lft.hard_use_expires_seconds) {
334 time64_t tmo = xp->lft.hard_use_expires_seconds +
335 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
336 if (tmo <= 0)
337 goto expired;
338 if (tmo < next)
339 next = tmo;
340 }
341 if (xp->lft.soft_add_expires_seconds) {
342 time64_t tmo = xp->lft.soft_add_expires_seconds +
343 xp->curlft.add_time - now;
344 if (tmo <= 0) {
345 warn = 1;
346 tmo = XFRM_KM_TIMEOUT;
347 }
348 if (tmo < next)
349 next = tmo;
350 }
351 if (xp->lft.soft_use_expires_seconds) {
352 time64_t tmo = xp->lft.soft_use_expires_seconds +
353 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
354 if (tmo <= 0) {
355 warn = 1;
356 tmo = XFRM_KM_TIMEOUT;
357 }
358 if (tmo < next)
359 next = tmo;
360 }
361
362 if (warn)
363 km_policy_expired(xp, dir, 0, 0);
364 if (next != TIME64_MAX &&
365 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
366 xfrm_pol_hold(xp);
367
368 out:
369 read_unlock(&xp->lock);
370 xfrm_pol_put(xp);
371 return;
372
373 expired:
374 read_unlock(&xp->lock);
375 if (!xfrm_policy_delete(xp, dir))
376 km_policy_expired(xp, dir, 1, 0);
377 xfrm_pol_put(xp);
378 }
379
380 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
381 * SPD calls.
382 */
383
384 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
385 {
386 struct xfrm_policy *policy;
387
388 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
389
390 if (policy) {
391 write_pnet(&policy->xp_net, net);
392 INIT_LIST_HEAD(&policy->walk.all);
393 INIT_HLIST_NODE(&policy->bydst_inexact_list);
394 INIT_HLIST_NODE(&policy->bydst);
395 INIT_HLIST_NODE(&policy->byidx);
396 rwlock_init(&policy->lock);
397 refcount_set(&policy->refcnt, 1);
398 skb_queue_head_init(&policy->polq.hold_queue);
399 timer_setup(&policy->timer, xfrm_policy_timer, 0);
400 timer_setup(&policy->polq.hold_timer,
401 xfrm_policy_queue_process, 0);
402 }
403 return policy;
404 }
405 EXPORT_SYMBOL(xfrm_policy_alloc);
406
407 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
408 {
409 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
410
411 security_xfrm_policy_free(policy->security);
412 kfree(policy);
413 }
414
415 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
416
417 void xfrm_policy_destroy(struct xfrm_policy *policy)
418 {
419 BUG_ON(!policy->walk.dead);
420
421 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
422 BUG();
423
424 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
425 }
426 EXPORT_SYMBOL(xfrm_policy_destroy);
427
428 /* Rule must be locked. Release descendant resources, announce
429 * entry dead. The rule must be unlinked from lists to the moment.
430 */
431
432 static void xfrm_policy_kill(struct xfrm_policy *policy)
433 {
434 policy->walk.dead = 1;
435
436 atomic_inc(&policy->genid);
437
438 if (del_timer(&policy->polq.hold_timer))
439 xfrm_pol_put(policy);
440 skb_queue_purge(&policy->polq.hold_queue);
441
442 if (del_timer(&policy->timer))
443 xfrm_pol_put(policy);
444
445 xfrm_pol_put(policy);
446 }
447
448 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
449
450 static inline unsigned int idx_hash(struct net *net, u32 index)
451 {
452 return __idx_hash(index, net->xfrm.policy_idx_hmask);
453 }
454
455 /* calculate policy hash thresholds */
456 static void __get_hash_thresh(struct net *net,
457 unsigned short family, int dir,
458 u8 *dbits, u8 *sbits)
459 {
460 switch (family) {
461 case AF_INET:
462 *dbits = net->xfrm.policy_bydst[dir].dbits4;
463 *sbits = net->xfrm.policy_bydst[dir].sbits4;
464 break;
465
466 case AF_INET6:
467 *dbits = net->xfrm.policy_bydst[dir].dbits6;
468 *sbits = net->xfrm.policy_bydst[dir].sbits6;
469 break;
470
471 default:
472 *dbits = 0;
473 *sbits = 0;
474 }
475 }
476
477 static struct hlist_head *policy_hash_bysel(struct net *net,
478 const struct xfrm_selector *sel,
479 unsigned short family, int dir)
480 {
481 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
482 unsigned int hash;
483 u8 dbits;
484 u8 sbits;
485
486 __get_hash_thresh(net, family, dir, &dbits, &sbits);
487 hash = __sel_hash(sel, family, hmask, dbits, sbits);
488
489 if (hash == hmask + 1)
490 return NULL;
491
492 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
493 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
494 }
495
496 static struct hlist_head *policy_hash_direct(struct net *net,
497 const xfrm_address_t *daddr,
498 const xfrm_address_t *saddr,
499 unsigned short family, int dir)
500 {
501 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
502 unsigned int hash;
503 u8 dbits;
504 u8 sbits;
505
506 __get_hash_thresh(net, family, dir, &dbits, &sbits);
507 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
508
509 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
510 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
511 }
512
513 static void xfrm_dst_hash_transfer(struct net *net,
514 struct hlist_head *list,
515 struct hlist_head *ndsttable,
516 unsigned int nhashmask,
517 int dir)
518 {
519 struct hlist_node *tmp, *entry0 = NULL;
520 struct xfrm_policy *pol;
521 unsigned int h0 = 0;
522 u8 dbits;
523 u8 sbits;
524
525 redo:
526 hlist_for_each_entry_safe(pol, tmp, list, bydst) {
527 unsigned int h;
528
529 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
530 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
531 pol->family, nhashmask, dbits, sbits);
532 if (!entry0) {
533 hlist_del_rcu(&pol->bydst);
534 hlist_add_head_rcu(&pol->bydst, ndsttable + h);
535 h0 = h;
536 } else {
537 if (h != h0)
538 continue;
539 hlist_del_rcu(&pol->bydst);
540 hlist_add_behind_rcu(&pol->bydst, entry0);
541 }
542 entry0 = &pol->bydst;
543 }
544 if (!hlist_empty(list)) {
545 entry0 = NULL;
546 goto redo;
547 }
548 }
549
550 static void xfrm_idx_hash_transfer(struct hlist_head *list,
551 struct hlist_head *nidxtable,
552 unsigned int nhashmask)
553 {
554 struct hlist_node *tmp;
555 struct xfrm_policy *pol;
556
557 hlist_for_each_entry_safe(pol, tmp, list, byidx) {
558 unsigned int h;
559
560 h = __idx_hash(pol->index, nhashmask);
561 hlist_add_head(&pol->byidx, nidxtable+h);
562 }
563 }
564
565 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
566 {
567 return ((old_hmask + 1) << 1) - 1;
568 }
569
570 static void xfrm_bydst_resize(struct net *net, int dir)
571 {
572 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
573 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
574 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
575 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
576 struct hlist_head *odst;
577 int i;
578
579 if (!ndst)
580 return;
581
582 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
583 write_seqcount_begin(&xfrm_policy_hash_generation);
584
585 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
586 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
587
588 for (i = hmask; i >= 0; i--)
589 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
590
591 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
592 net->xfrm.policy_bydst[dir].hmask = nhashmask;
593
594 write_seqcount_end(&xfrm_policy_hash_generation);
595 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
596
597 synchronize_rcu();
598
599 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
600 }
601
602 static void xfrm_byidx_resize(struct net *net, int total)
603 {
604 unsigned int hmask = net->xfrm.policy_idx_hmask;
605 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
606 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
607 struct hlist_head *oidx = net->xfrm.policy_byidx;
608 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
609 int i;
610
611 if (!nidx)
612 return;
613
614 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
615
616 for (i = hmask; i >= 0; i--)
617 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
618
619 net->xfrm.policy_byidx = nidx;
620 net->xfrm.policy_idx_hmask = nhashmask;
621
622 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
623
624 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
625 }
626
627 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
628 {
629 unsigned int cnt = net->xfrm.policy_count[dir];
630 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
631
632 if (total)
633 *total += cnt;
634
635 if ((hmask + 1) < xfrm_policy_hashmax &&
636 cnt > hmask)
637 return 1;
638
639 return 0;
640 }
641
642 static inline int xfrm_byidx_should_resize(struct net *net, int total)
643 {
644 unsigned int hmask = net->xfrm.policy_idx_hmask;
645
646 if ((hmask + 1) < xfrm_policy_hashmax &&
647 total > hmask)
648 return 1;
649
650 return 0;
651 }
652
653 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
654 {
655 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
656 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
657 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
658 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
659 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
660 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
661 si->spdhcnt = net->xfrm.policy_idx_hmask;
662 si->spdhmcnt = xfrm_policy_hashmax;
663 }
664 EXPORT_SYMBOL(xfrm_spd_getinfo);
665
666 static DEFINE_MUTEX(hash_resize_mutex);
667 static void xfrm_hash_resize(struct work_struct *work)
668 {
669 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
670 int dir, total;
671
672 mutex_lock(&hash_resize_mutex);
673
674 total = 0;
675 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
676 if (xfrm_bydst_should_resize(net, dir, &total))
677 xfrm_bydst_resize(net, dir);
678 }
679 if (xfrm_byidx_should_resize(net, total))
680 xfrm_byidx_resize(net, total);
681
682 mutex_unlock(&hash_resize_mutex);
683 }
684
685 /* Make sure *pol can be inserted into fastbin.
686 * Useful to check that later insert requests will be sucessful
687 * (provided xfrm_policy_lock is held throughout).
688 */
689 static struct xfrm_pol_inexact_bin *
690 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
691 {
692 struct xfrm_pol_inexact_bin *bin, *prev;
693 struct xfrm_pol_inexact_key k = {
694 .family = pol->family,
695 .type = pol->type,
696 .dir = dir,
697 .if_id = pol->if_id,
698 };
699 struct net *net = xp_net(pol);
700
701 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
702
703 write_pnet(&k.net, net);
704 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
705 xfrm_pol_inexact_params);
706 if (bin)
707 return bin;
708
709 bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
710 if (!bin)
711 return NULL;
712
713 bin->k = k;
714 INIT_HLIST_HEAD(&bin->hhead);
715 bin->root_d = RB_ROOT;
716 bin->root_s = RB_ROOT;
717 seqcount_init(&bin->count);
718
719 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
720 &bin->k, &bin->head,
721 xfrm_pol_inexact_params);
722 if (!prev) {
723 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
724 return bin;
725 }
726
727 kfree(bin);
728
729 return IS_ERR(prev) ? NULL : prev;
730 }
731
732 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
733 int family, u8 prefixlen)
734 {
735 if (xfrm_addr_any(addr, family))
736 return true;
737
738 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
739 return true;
740
741 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
742 return true;
743
744 return false;
745 }
746
747 static bool
748 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
749 {
750 const xfrm_address_t *addr;
751 bool saddr_any, daddr_any;
752 u8 prefixlen;
753
754 addr = &policy->selector.saddr;
755 prefixlen = policy->selector.prefixlen_s;
756
757 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
758 policy->family,
759 prefixlen);
760 addr = &policy->selector.daddr;
761 prefixlen = policy->selector.prefixlen_d;
762 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
763 policy->family,
764 prefixlen);
765 return saddr_any && daddr_any;
766 }
767
768 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
769 const xfrm_address_t *addr, u8 prefixlen)
770 {
771 node->addr = *addr;
772 node->prefixlen = prefixlen;
773 }
774
775 static struct xfrm_pol_inexact_node *
776 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
777 {
778 struct xfrm_pol_inexact_node *node;
779
780 node = kzalloc(sizeof(*node), GFP_ATOMIC);
781 if (node)
782 xfrm_pol_inexact_node_init(node, addr, prefixlen);
783
784 return node;
785 }
786
787 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
788 const xfrm_address_t *b,
789 u8 prefixlen, u16 family)
790 {
791 unsigned int pdw, pbi;
792 int delta = 0;
793
794 switch (family) {
795 case AF_INET:
796 if (sizeof(long) == 4 && prefixlen == 0)
797 return ntohl(a->a4) - ntohl(b->a4);
798 return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) -
799 (ntohl(b->a4) & ((~0UL << (32 - prefixlen))));
800 case AF_INET6:
801 pdw = prefixlen >> 5;
802 pbi = prefixlen & 0x1f;
803
804 if (pdw) {
805 delta = memcmp(a->a6, b->a6, pdw << 2);
806 if (delta)
807 return delta;
808 }
809 if (pbi) {
810 u32 mask = ~0u << (32 - pbi);
811
812 delta = (ntohl(a->a6[pdw]) & mask) -
813 (ntohl(b->a6[pdw]) & mask);
814 }
815 break;
816 default:
817 break;
818 }
819
820 return delta;
821 }
822
823 static void xfrm_policy_inexact_list_reinsert(struct net *net,
824 struct xfrm_pol_inexact_node *n,
825 u16 family)
826 {
827 unsigned int matched_s, matched_d;
828 struct xfrm_policy *policy, *p;
829
830 matched_s = 0;
831 matched_d = 0;
832
833 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
834 struct hlist_node *newpos = NULL;
835 bool matches_s, matches_d;
836
837 if (!policy->bydst_reinsert)
838 continue;
839
840 WARN_ON_ONCE(policy->family != family);
841
842 policy->bydst_reinsert = false;
843 hlist_for_each_entry(p, &n->hhead, bydst) {
844 if (policy->priority > p->priority)
845 newpos = &p->bydst;
846 else if (policy->priority == p->priority &&
847 policy->pos > p->pos)
848 newpos = &p->bydst;
849 else
850 break;
851 }
852
853 if (newpos)
854 hlist_add_behind_rcu(&policy->bydst, newpos);
855 else
856 hlist_add_head_rcu(&policy->bydst, &n->hhead);
857
858 /* paranoia checks follow.
859 * Check that the reinserted policy matches at least
860 * saddr or daddr for current node prefix.
861 *
862 * Matching both is fine, matching saddr in one policy
863 * (but not daddr) and then matching only daddr in another
864 * is a bug.
865 */
866 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
867 &n->addr,
868 n->prefixlen,
869 family) == 0;
870 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
871 &n->addr,
872 n->prefixlen,
873 family) == 0;
874 if (matches_s && matches_d)
875 continue;
876
877 WARN_ON_ONCE(!matches_s && !matches_d);
878 if (matches_s)
879 matched_s++;
880 if (matches_d)
881 matched_d++;
882 WARN_ON_ONCE(matched_s && matched_d);
883 }
884 }
885
886 static void xfrm_policy_inexact_node_reinsert(struct net *net,
887 struct xfrm_pol_inexact_node *n,
888 struct rb_root *new,
889 u16 family)
890 {
891 struct xfrm_pol_inexact_node *node;
892 struct rb_node **p, *parent;
893
894 /* we should not have another subtree here */
895 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
896 restart:
897 parent = NULL;
898 p = &new->rb_node;
899 while (*p) {
900 u8 prefixlen;
901 int delta;
902
903 parent = *p;
904 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
905
906 prefixlen = min(node->prefixlen, n->prefixlen);
907
908 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
909 prefixlen, family);
910 if (delta < 0) {
911 p = &parent->rb_left;
912 } else if (delta > 0) {
913 p = &parent->rb_right;
914 } else {
915 bool same_prefixlen = node->prefixlen == n->prefixlen;
916 struct xfrm_policy *tmp;
917
918 hlist_for_each_entry(tmp, &n->hhead, bydst) {
919 tmp->bydst_reinsert = true;
920 hlist_del_rcu(&tmp->bydst);
921 }
922
923 node->prefixlen = prefixlen;
924
925 xfrm_policy_inexact_list_reinsert(net, node, family);
926
927 if (same_prefixlen) {
928 kfree_rcu(n, rcu);
929 return;
930 }
931
932 rb_erase(*p, new);
933 kfree_rcu(n, rcu);
934 n = node;
935 goto restart;
936 }
937 }
938
939 rb_link_node_rcu(&n->node, parent, p);
940 rb_insert_color(&n->node, new);
941 }
942
943 /* merge nodes v and n */
944 static void xfrm_policy_inexact_node_merge(struct net *net,
945 struct xfrm_pol_inexact_node *v,
946 struct xfrm_pol_inexact_node *n,
947 u16 family)
948 {
949 struct xfrm_pol_inexact_node *node;
950 struct xfrm_policy *tmp;
951 struct rb_node *rnode;
952
953 /* To-be-merged node v has a subtree.
954 *
955 * Dismantle it and insert its nodes to n->root.
956 */
957 while ((rnode = rb_first(&v->root)) != NULL) {
958 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
959 rb_erase(&node->node, &v->root);
960 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
961 family);
962 }
963
964 hlist_for_each_entry(tmp, &v->hhead, bydst) {
965 tmp->bydst_reinsert = true;
966 hlist_del_rcu(&tmp->bydst);
967 }
968
969 xfrm_policy_inexact_list_reinsert(net, n, family);
970 }
971
972 static struct xfrm_pol_inexact_node *
973 xfrm_policy_inexact_insert_node(struct net *net,
974 struct rb_root *root,
975 xfrm_address_t *addr,
976 u16 family, u8 prefixlen, u8 dir)
977 {
978 struct xfrm_pol_inexact_node *cached = NULL;
979 struct rb_node **p, *parent = NULL;
980 struct xfrm_pol_inexact_node *node;
981
982 p = &root->rb_node;
983 while (*p) {
984 int delta;
985
986 parent = *p;
987 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
988
989 delta = xfrm_policy_addr_delta(addr, &node->addr,
990 node->prefixlen,
991 family);
992 if (delta == 0 && prefixlen >= node->prefixlen) {
993 WARN_ON_ONCE(cached); /* ipsec policies got lost */
994 return node;
995 }
996
997 if (delta < 0)
998 p = &parent->rb_left;
999 else
1000 p = &parent->rb_right;
1001
1002 if (prefixlen < node->prefixlen) {
1003 delta = xfrm_policy_addr_delta(addr, &node->addr,
1004 prefixlen,
1005 family);
1006 if (delta)
1007 continue;
1008
1009 /* This node is a subnet of the new prefix. It needs
1010 * to be removed and re-inserted with the smaller
1011 * prefix and all nodes that are now also covered
1012 * by the reduced prefixlen.
1013 */
1014 rb_erase(&node->node, root);
1015
1016 if (!cached) {
1017 xfrm_pol_inexact_node_init(node, addr,
1018 prefixlen);
1019 cached = node;
1020 } else {
1021 /* This node also falls within the new
1022 * prefixlen. Merge the to-be-reinserted
1023 * node and this one.
1024 */
1025 xfrm_policy_inexact_node_merge(net, node,
1026 cached, family);
1027 kfree_rcu(node, rcu);
1028 }
1029
1030 /* restart */
1031 p = &root->rb_node;
1032 parent = NULL;
1033 }
1034 }
1035
1036 node = cached;
1037 if (!node) {
1038 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1039 if (!node)
1040 return NULL;
1041 }
1042
1043 rb_link_node_rcu(&node->node, parent, p);
1044 rb_insert_color(&node->node, root);
1045
1046 return node;
1047 }
1048
1049 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1050 {
1051 struct xfrm_pol_inexact_node *node;
1052 struct rb_node *rn = rb_first(r);
1053
1054 while (rn) {
1055 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1056
1057 xfrm_policy_inexact_gc_tree(&node->root, rm);
1058 rn = rb_next(rn);
1059
1060 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1061 WARN_ON_ONCE(rm);
1062 continue;
1063 }
1064
1065 rb_erase(&node->node, r);
1066 kfree_rcu(node, rcu);
1067 }
1068 }
1069
1070 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1071 {
1072 write_seqcount_begin(&b->count);
1073 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1074 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1075 write_seqcount_end(&b->count);
1076
1077 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1078 !hlist_empty(&b->hhead)) {
1079 WARN_ON_ONCE(net_exit);
1080 return;
1081 }
1082
1083 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1084 xfrm_pol_inexact_params) == 0) {
1085 list_del(&b->inexact_bins);
1086 kfree_rcu(b, rcu);
1087 }
1088 }
1089
1090 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1091 {
1092 struct net *net = read_pnet(&b->k.net);
1093
1094 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1095 __xfrm_policy_inexact_prune_bin(b, false);
1096 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1097 }
1098
1099 static void __xfrm_policy_inexact_flush(struct net *net)
1100 {
1101 struct xfrm_pol_inexact_bin *bin, *t;
1102
1103 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1104
1105 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1106 __xfrm_policy_inexact_prune_bin(bin, false);
1107 }
1108
1109 static struct hlist_head *
1110 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1111 struct xfrm_policy *policy, u8 dir)
1112 {
1113 struct xfrm_pol_inexact_node *n;
1114 struct net *net;
1115
1116 net = xp_net(policy);
1117 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1118
1119 if (xfrm_policy_inexact_insert_use_any_list(policy))
1120 return &bin->hhead;
1121
1122 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1123 policy->family,
1124 policy->selector.prefixlen_d)) {
1125 write_seqcount_begin(&bin->count);
1126 n = xfrm_policy_inexact_insert_node(net,
1127 &bin->root_s,
1128 &policy->selector.saddr,
1129 policy->family,
1130 policy->selector.prefixlen_s,
1131 dir);
1132 write_seqcount_end(&bin->count);
1133 if (!n)
1134 return NULL;
1135
1136 return &n->hhead;
1137 }
1138
1139 /* daddr is fixed */
1140 write_seqcount_begin(&bin->count);
1141 n = xfrm_policy_inexact_insert_node(net,
1142 &bin->root_d,
1143 &policy->selector.daddr,
1144 policy->family,
1145 policy->selector.prefixlen_d, dir);
1146 write_seqcount_end(&bin->count);
1147 if (!n)
1148 return NULL;
1149
1150 /* saddr is wildcard */
1151 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1152 policy->family,
1153 policy->selector.prefixlen_s))
1154 return &n->hhead;
1155
1156 write_seqcount_begin(&bin->count);
1157 n = xfrm_policy_inexact_insert_node(net,
1158 &n->root,
1159 &policy->selector.saddr,
1160 policy->family,
1161 policy->selector.prefixlen_s, dir);
1162 write_seqcount_end(&bin->count);
1163 if (!n)
1164 return NULL;
1165
1166 return &n->hhead;
1167 }
1168
1169 static struct xfrm_policy *
1170 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1171 {
1172 struct xfrm_pol_inexact_bin *bin;
1173 struct xfrm_policy *delpol;
1174 struct hlist_head *chain;
1175 struct net *net;
1176
1177 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1178 if (!bin)
1179 return ERR_PTR(-ENOMEM);
1180
1181 net = xp_net(policy);
1182 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1183
1184 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1185 if (!chain) {
1186 __xfrm_policy_inexact_prune_bin(bin, false);
1187 return ERR_PTR(-ENOMEM);
1188 }
1189
1190 delpol = xfrm_policy_insert_list(chain, policy, excl);
1191 if (delpol && excl) {
1192 __xfrm_policy_inexact_prune_bin(bin, false);
1193 return ERR_PTR(-EEXIST);
1194 }
1195
1196 chain = &net->xfrm.policy_inexact[dir];
1197 xfrm_policy_insert_inexact_list(chain, policy);
1198
1199 if (delpol)
1200 __xfrm_policy_inexact_prune_bin(bin, false);
1201
1202 return delpol;
1203 }
1204
1205 static void xfrm_hash_rebuild(struct work_struct *work)
1206 {
1207 struct net *net = container_of(work, struct net,
1208 xfrm.policy_hthresh.work);
1209 unsigned int hmask;
1210 struct xfrm_policy *pol;
1211 struct xfrm_policy *policy;
1212 struct hlist_head *chain;
1213 struct hlist_head *odst;
1214 struct hlist_node *newpos;
1215 int i;
1216 int dir;
1217 unsigned seq;
1218 u8 lbits4, rbits4, lbits6, rbits6;
1219
1220 mutex_lock(&hash_resize_mutex);
1221
1222 /* read selector prefixlen thresholds */
1223 do {
1224 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1225
1226 lbits4 = net->xfrm.policy_hthresh.lbits4;
1227 rbits4 = net->xfrm.policy_hthresh.rbits4;
1228 lbits6 = net->xfrm.policy_hthresh.lbits6;
1229 rbits6 = net->xfrm.policy_hthresh.rbits6;
1230 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1231
1232 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1233 write_seqcount_begin(&xfrm_policy_hash_generation);
1234
1235 /* make sure that we can insert the indirect policies again before
1236 * we start with destructive action.
1237 */
1238 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1239 struct xfrm_pol_inexact_bin *bin;
1240 u8 dbits, sbits;
1241
1242 dir = xfrm_policy_id2dir(policy->index);
1243 if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1244 continue;
1245
1246 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1247 if (policy->family == AF_INET) {
1248 dbits = rbits4;
1249 sbits = lbits4;
1250 } else {
1251 dbits = rbits6;
1252 sbits = lbits6;
1253 }
1254 } else {
1255 if (policy->family == AF_INET) {
1256 dbits = lbits4;
1257 sbits = rbits4;
1258 } else {
1259 dbits = lbits6;
1260 sbits = rbits6;
1261 }
1262 }
1263
1264 if (policy->selector.prefixlen_d < dbits ||
1265 policy->selector.prefixlen_s < sbits)
1266 continue;
1267
1268 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1269 if (!bin)
1270 goto out_unlock;
1271
1272 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1273 goto out_unlock;
1274 }
1275
1276 /* reset the bydst and inexact table in all directions */
1277 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1278 struct hlist_node *n;
1279
1280 hlist_for_each_entry_safe(policy, n,
1281 &net->xfrm.policy_inexact[dir],
1282 bydst_inexact_list) {
1283 hlist_del_rcu(&policy->bydst);
1284 hlist_del_init(&policy->bydst_inexact_list);
1285 }
1286
1287 hmask = net->xfrm.policy_bydst[dir].hmask;
1288 odst = net->xfrm.policy_bydst[dir].table;
1289 for (i = hmask; i >= 0; i--) {
1290 hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1291 hlist_del_rcu(&policy->bydst);
1292 }
1293 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1294 /* dir out => dst = remote, src = local */
1295 net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1296 net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1297 net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1298 net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1299 } else {
1300 /* dir in/fwd => dst = local, src = remote */
1301 net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1302 net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1303 net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1304 net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1305 }
1306 }
1307
1308 /* re-insert all policies by order of creation */
1309 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1310 if (policy->walk.dead)
1311 continue;
1312 dir = xfrm_policy_id2dir(policy->index);
1313 if (dir >= XFRM_POLICY_MAX) {
1314 /* skip socket policies */
1315 continue;
1316 }
1317 newpos = NULL;
1318 chain = policy_hash_bysel(net, &policy->selector,
1319 policy->family, dir);
1320
1321 if (!chain) {
1322 void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1323
1324 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1325 continue;
1326 }
1327
1328 hlist_for_each_entry(pol, chain, bydst) {
1329 if (policy->priority >= pol->priority)
1330 newpos = &pol->bydst;
1331 else
1332 break;
1333 }
1334 if (newpos)
1335 hlist_add_behind_rcu(&policy->bydst, newpos);
1336 else
1337 hlist_add_head_rcu(&policy->bydst, chain);
1338 }
1339
1340 out_unlock:
1341 __xfrm_policy_inexact_flush(net);
1342 write_seqcount_end(&xfrm_policy_hash_generation);
1343 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1344
1345 mutex_unlock(&hash_resize_mutex);
1346 }
1347
1348 void xfrm_policy_hash_rebuild(struct net *net)
1349 {
1350 schedule_work(&net->xfrm.policy_hthresh.work);
1351 }
1352 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1353
1354 /* Generate new index... KAME seems to generate them ordered by cost
1355 * of an absolute inpredictability of ordering of rules. This will not pass. */
1356 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1357 {
1358 static u32 idx_generator;
1359
1360 for (;;) {
1361 struct hlist_head *list;
1362 struct xfrm_policy *p;
1363 u32 idx;
1364 int found;
1365
1366 if (!index) {
1367 idx = (idx_generator | dir);
1368 idx_generator += 8;
1369 } else {
1370 idx = index;
1371 index = 0;
1372 }
1373
1374 if (idx == 0)
1375 idx = 8;
1376 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1377 found = 0;
1378 hlist_for_each_entry(p, list, byidx) {
1379 if (p->index == idx) {
1380 found = 1;
1381 break;
1382 }
1383 }
1384 if (!found)
1385 return idx;
1386 }
1387 }
1388
1389 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1390 {
1391 u32 *p1 = (u32 *) s1;
1392 u32 *p2 = (u32 *) s2;
1393 int len = sizeof(struct xfrm_selector) / sizeof(u32);
1394 int i;
1395
1396 for (i = 0; i < len; i++) {
1397 if (p1[i] != p2[i])
1398 return 1;
1399 }
1400
1401 return 0;
1402 }
1403
1404 static void xfrm_policy_requeue(struct xfrm_policy *old,
1405 struct xfrm_policy *new)
1406 {
1407 struct xfrm_policy_queue *pq = &old->polq;
1408 struct sk_buff_head list;
1409
1410 if (skb_queue_empty(&pq->hold_queue))
1411 return;
1412
1413 __skb_queue_head_init(&list);
1414
1415 spin_lock_bh(&pq->hold_queue.lock);
1416 skb_queue_splice_init(&pq->hold_queue, &list);
1417 if (del_timer(&pq->hold_timer))
1418 xfrm_pol_put(old);
1419 spin_unlock_bh(&pq->hold_queue.lock);
1420
1421 pq = &new->polq;
1422
1423 spin_lock_bh(&pq->hold_queue.lock);
1424 skb_queue_splice(&list, &pq->hold_queue);
1425 pq->timeout = XFRM_QUEUE_TMO_MIN;
1426 if (!mod_timer(&pq->hold_timer, jiffies))
1427 xfrm_pol_hold(new);
1428 spin_unlock_bh(&pq->hold_queue.lock);
1429 }
1430
1431 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
1432 struct xfrm_policy *pol)
1433 {
1434 u32 mark = policy->mark.v & policy->mark.m;
1435
1436 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
1437 return true;
1438
1439 if ((mark & pol->mark.m) == 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->flags |= DST_HOST;
2614 dst1->lastuse = now;
2615
2616 dst1->input = dst_discard;
2617
2618 rcu_read_lock();
2619 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2620 if (likely(afinfo))
2621 dst1->output = afinfo->output;
2622 else
2623 dst1->output = dst_discard_out;
2624 rcu_read_unlock();
2625
2626 xdst_prev = xdst;
2627
2628 header_len += xfrm[i]->props.header_len;
2629 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2630 nfheader_len += xfrm[i]->props.header_len;
2631 trailer_len += xfrm[i]->props.trailer_len;
2632 }
2633
2634 xfrm_dst_set_child(xdst_prev, dst);
2635 xdst0->path = dst;
2636
2637 err = -ENODEV;
2638 dev = dst->dev;
2639 if (!dev)
2640 goto free_dst;
2641
2642 xfrm_init_path(xdst0, dst, nfheader_len);
2643 xfrm_init_pmtu(bundle, nx);
2644
2645 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2646 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2647 err = xfrm_fill_dst(xdst_prev, dev, fl);
2648 if (err)
2649 goto free_dst;
2650
2651 xdst_prev->u.dst.header_len = header_len;
2652 xdst_prev->u.dst.trailer_len = trailer_len;
2653 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2654 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2655 }
2656
2657 return &xdst0->u.dst;
2658
2659 put_states:
2660 for (; i < nx; i++)
2661 xfrm_state_put(xfrm[i]);
2662 free_dst:
2663 if (xdst0)
2664 dst_release_immediate(&xdst0->u.dst);
2665
2666 return ERR_PTR(err);
2667 }
2668
2669 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2670 struct xfrm_policy **pols,
2671 int *num_pols, int *num_xfrms)
2672 {
2673 int i;
2674
2675 if (*num_pols == 0 || !pols[0]) {
2676 *num_pols = 0;
2677 *num_xfrms = 0;
2678 return 0;
2679 }
2680 if (IS_ERR(pols[0]))
2681 return PTR_ERR(pols[0]);
2682
2683 *num_xfrms = pols[0]->xfrm_nr;
2684
2685 #ifdef CONFIG_XFRM_SUB_POLICY
2686 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
2687 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2688 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2689 XFRM_POLICY_TYPE_MAIN,
2690 fl, family,
2691 XFRM_POLICY_OUT,
2692 pols[0]->if_id);
2693 if (pols[1]) {
2694 if (IS_ERR(pols[1])) {
2695 xfrm_pols_put(pols, *num_pols);
2696 return PTR_ERR(pols[1]);
2697 }
2698 (*num_pols)++;
2699 (*num_xfrms) += pols[1]->xfrm_nr;
2700 }
2701 }
2702 #endif
2703 for (i = 0; i < *num_pols; i++) {
2704 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2705 *num_xfrms = -1;
2706 break;
2707 }
2708 }
2709
2710 return 0;
2711
2712 }
2713
2714 static struct xfrm_dst *
2715 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2716 const struct flowi *fl, u16 family,
2717 struct dst_entry *dst_orig)
2718 {
2719 struct net *net = xp_net(pols[0]);
2720 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2721 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2722 struct xfrm_dst *xdst;
2723 struct dst_entry *dst;
2724 int err;
2725
2726 /* Try to instantiate a bundle */
2727 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2728 if (err <= 0) {
2729 if (err == 0)
2730 return NULL;
2731
2732 if (err != -EAGAIN)
2733 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2734 return ERR_PTR(err);
2735 }
2736
2737 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2738 if (IS_ERR(dst)) {
2739 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2740 return ERR_CAST(dst);
2741 }
2742
2743 xdst = (struct xfrm_dst *)dst;
2744 xdst->num_xfrms = err;
2745 xdst->num_pols = num_pols;
2746 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2747 xdst->policy_genid = atomic_read(&pols[0]->genid);
2748
2749 return xdst;
2750 }
2751
2752 static void xfrm_policy_queue_process(struct timer_list *t)
2753 {
2754 struct sk_buff *skb;
2755 struct sock *sk;
2756 struct dst_entry *dst;
2757 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2758 struct net *net = xp_net(pol);
2759 struct xfrm_policy_queue *pq = &pol->polq;
2760 struct flowi fl;
2761 struct sk_buff_head list;
2762
2763 spin_lock(&pq->hold_queue.lock);
2764 skb = skb_peek(&pq->hold_queue);
2765 if (!skb) {
2766 spin_unlock(&pq->hold_queue.lock);
2767 goto out;
2768 }
2769 dst = skb_dst(skb);
2770 sk = skb->sk;
2771 xfrm_decode_session(skb, &fl, dst->ops->family);
2772 spin_unlock(&pq->hold_queue.lock);
2773
2774 dst_hold(xfrm_dst_path(dst));
2775 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2776 if (IS_ERR(dst))
2777 goto purge_queue;
2778
2779 if (dst->flags & DST_XFRM_QUEUE) {
2780 dst_release(dst);
2781
2782 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2783 goto purge_queue;
2784
2785 pq->timeout = pq->timeout << 1;
2786 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2787 xfrm_pol_hold(pol);
2788 goto out;
2789 }
2790
2791 dst_release(dst);
2792
2793 __skb_queue_head_init(&list);
2794
2795 spin_lock(&pq->hold_queue.lock);
2796 pq->timeout = 0;
2797 skb_queue_splice_init(&pq->hold_queue, &list);
2798 spin_unlock(&pq->hold_queue.lock);
2799
2800 while (!skb_queue_empty(&list)) {
2801 skb = __skb_dequeue(&list);
2802
2803 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2804 dst_hold(xfrm_dst_path(skb_dst(skb)));
2805 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2806 if (IS_ERR(dst)) {
2807 kfree_skb(skb);
2808 continue;
2809 }
2810
2811 nf_reset_ct(skb);
2812 skb_dst_drop(skb);
2813 skb_dst_set(skb, dst);
2814
2815 dst_output(net, skb->sk, skb);
2816 }
2817
2818 out:
2819 xfrm_pol_put(pol);
2820 return;
2821
2822 purge_queue:
2823 pq->timeout = 0;
2824 skb_queue_purge(&pq->hold_queue);
2825 xfrm_pol_put(pol);
2826 }
2827
2828 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2829 {
2830 unsigned long sched_next;
2831 struct dst_entry *dst = skb_dst(skb);
2832 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2833 struct xfrm_policy *pol = xdst->pols[0];
2834 struct xfrm_policy_queue *pq = &pol->polq;
2835
2836 if (unlikely(skb_fclone_busy(sk, skb))) {
2837 kfree_skb(skb);
2838 return 0;
2839 }
2840
2841 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2842 kfree_skb(skb);
2843 return -EAGAIN;
2844 }
2845
2846 skb_dst_force(skb);
2847
2848 spin_lock_bh(&pq->hold_queue.lock);
2849
2850 if (!pq->timeout)
2851 pq->timeout = XFRM_QUEUE_TMO_MIN;
2852
2853 sched_next = jiffies + pq->timeout;
2854
2855 if (del_timer(&pq->hold_timer)) {
2856 if (time_before(pq->hold_timer.expires, sched_next))
2857 sched_next = pq->hold_timer.expires;
2858 xfrm_pol_put(pol);
2859 }
2860
2861 __skb_queue_tail(&pq->hold_queue, skb);
2862 if (!mod_timer(&pq->hold_timer, sched_next))
2863 xfrm_pol_hold(pol);
2864
2865 spin_unlock_bh(&pq->hold_queue.lock);
2866
2867 return 0;
2868 }
2869
2870 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2871 struct xfrm_flo *xflo,
2872 const struct flowi *fl,
2873 int num_xfrms,
2874 u16 family)
2875 {
2876 int err;
2877 struct net_device *dev;
2878 struct dst_entry *dst;
2879 struct dst_entry *dst1;
2880 struct xfrm_dst *xdst;
2881
2882 xdst = xfrm_alloc_dst(net, family);
2883 if (IS_ERR(xdst))
2884 return xdst;
2885
2886 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2887 net->xfrm.sysctl_larval_drop ||
2888 num_xfrms <= 0)
2889 return xdst;
2890
2891 dst = xflo->dst_orig;
2892 dst1 = &xdst->u.dst;
2893 dst_hold(dst);
2894 xdst->route = dst;
2895
2896 dst_copy_metrics(dst1, dst);
2897
2898 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2899 dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2900 dst1->lastuse = jiffies;
2901
2902 dst1->input = dst_discard;
2903 dst1->output = xdst_queue_output;
2904
2905 dst_hold(dst);
2906 xfrm_dst_set_child(xdst, dst);
2907 xdst->path = dst;
2908
2909 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2910
2911 err = -ENODEV;
2912 dev = dst->dev;
2913 if (!dev)
2914 goto free_dst;
2915
2916 err = xfrm_fill_dst(xdst, dev, fl);
2917 if (err)
2918 goto free_dst;
2919
2920 out:
2921 return xdst;
2922
2923 free_dst:
2924 dst_release(dst1);
2925 xdst = ERR_PTR(err);
2926 goto out;
2927 }
2928
2929 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
2930 const struct flowi *fl,
2931 u16 family, u8 dir,
2932 struct xfrm_flo *xflo, u32 if_id)
2933 {
2934 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2935 int num_pols = 0, num_xfrms = 0, err;
2936 struct xfrm_dst *xdst;
2937
2938 /* Resolve policies to use if we couldn't get them from
2939 * previous cache entry */
2940 num_pols = 1;
2941 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
2942 err = xfrm_expand_policies(fl, family, pols,
2943 &num_pols, &num_xfrms);
2944 if (err < 0)
2945 goto inc_error;
2946 if (num_pols == 0)
2947 return NULL;
2948 if (num_xfrms <= 0)
2949 goto make_dummy_bundle;
2950
2951 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2952 xflo->dst_orig);
2953 if (IS_ERR(xdst)) {
2954 err = PTR_ERR(xdst);
2955 if (err == -EREMOTE) {
2956 xfrm_pols_put(pols, num_pols);
2957 return NULL;
2958 }
2959
2960 if (err != -EAGAIN)
2961 goto error;
2962 goto make_dummy_bundle;
2963 } else if (xdst == NULL) {
2964 num_xfrms = 0;
2965 goto make_dummy_bundle;
2966 }
2967
2968 return xdst;
2969
2970 make_dummy_bundle:
2971 /* We found policies, but there's no bundles to instantiate:
2972 * either because the policy blocks, has no transformations or
2973 * we could not build template (no xfrm_states).*/
2974 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2975 if (IS_ERR(xdst)) {
2976 xfrm_pols_put(pols, num_pols);
2977 return ERR_CAST(xdst);
2978 }
2979 xdst->num_pols = num_pols;
2980 xdst->num_xfrms = num_xfrms;
2981 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2982
2983 return xdst;
2984
2985 inc_error:
2986 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2987 error:
2988 xfrm_pols_put(pols, num_pols);
2989 return ERR_PTR(err);
2990 }
2991
2992 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2993 struct dst_entry *dst_orig)
2994 {
2995 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2996 struct dst_entry *ret;
2997
2998 if (!afinfo) {
2999 dst_release(dst_orig);
3000 return ERR_PTR(-EINVAL);
3001 } else {
3002 ret = afinfo->blackhole_route(net, dst_orig);
3003 }
3004 rcu_read_unlock();
3005
3006 return ret;
3007 }
3008
3009 /* Finds/creates a bundle for given flow and if_id
3010 *
3011 * At the moment we eat a raw IP route. Mostly to speed up lookups
3012 * on interfaces with disabled IPsec.
3013 *
3014 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3015 * compatibility
3016 */
3017 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3018 struct dst_entry *dst_orig,
3019 const struct flowi *fl,
3020 const struct sock *sk,
3021 int flags, u32 if_id)
3022 {
3023 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3024 struct xfrm_dst *xdst;
3025 struct dst_entry *dst, *route;
3026 u16 family = dst_orig->ops->family;
3027 u8 dir = XFRM_POLICY_OUT;
3028 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3029
3030 dst = NULL;
3031 xdst = NULL;
3032 route = NULL;
3033
3034 sk = sk_const_to_full_sk(sk);
3035 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3036 num_pols = 1;
3037 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3038 if_id);
3039 err = xfrm_expand_policies(fl, family, pols,
3040 &num_pols, &num_xfrms);
3041 if (err < 0)
3042 goto dropdst;
3043
3044 if (num_pols) {
3045 if (num_xfrms <= 0) {
3046 drop_pols = num_pols;
3047 goto no_transform;
3048 }
3049
3050 xdst = xfrm_resolve_and_create_bundle(
3051 pols, num_pols, fl,
3052 family, dst_orig);
3053
3054 if (IS_ERR(xdst)) {
3055 xfrm_pols_put(pols, num_pols);
3056 err = PTR_ERR(xdst);
3057 if (err == -EREMOTE)
3058 goto nopol;
3059
3060 goto dropdst;
3061 } else if (xdst == NULL) {
3062 num_xfrms = 0;
3063 drop_pols = num_pols;
3064 goto no_transform;
3065 }
3066
3067 route = xdst->route;
3068 }
3069 }
3070
3071 if (xdst == NULL) {
3072 struct xfrm_flo xflo;
3073
3074 xflo.dst_orig = dst_orig;
3075 xflo.flags = flags;
3076
3077 /* To accelerate a bit... */
3078 if ((dst_orig->flags & DST_NOXFRM) ||
3079 !net->xfrm.policy_count[XFRM_POLICY_OUT])
3080 goto nopol;
3081
3082 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3083 if (xdst == NULL)
3084 goto nopol;
3085 if (IS_ERR(xdst)) {
3086 err = PTR_ERR(xdst);
3087 goto dropdst;
3088 }
3089
3090 num_pols = xdst->num_pols;
3091 num_xfrms = xdst->num_xfrms;
3092 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3093 route = xdst->route;
3094 }
3095
3096 dst = &xdst->u.dst;
3097 if (route == NULL && num_xfrms > 0) {
3098 /* The only case when xfrm_bundle_lookup() returns a
3099 * bundle with null route, is when the template could
3100 * not be resolved. It means policies are there, but
3101 * bundle could not be created, since we don't yet
3102 * have the xfrm_state's. We need to wait for KM to
3103 * negotiate new SA's or bail out with error.*/
3104 if (net->xfrm.sysctl_larval_drop) {
3105 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3106 err = -EREMOTE;
3107 goto error;
3108 }
3109
3110 err = -EAGAIN;
3111
3112 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3113 goto error;
3114 }
3115
3116 no_transform:
3117 if (num_pols == 0)
3118 goto nopol;
3119
3120 if ((flags & XFRM_LOOKUP_ICMP) &&
3121 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3122 err = -ENOENT;
3123 goto error;
3124 }
3125
3126 for (i = 0; i < num_pols; i++)
3127 pols[i]->curlft.use_time = ktime_get_real_seconds();
3128
3129 if (num_xfrms < 0) {
3130 /* Prohibit the flow */
3131 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3132 err = -EPERM;
3133 goto error;
3134 } else if (num_xfrms > 0) {
3135 /* Flow transformed */
3136 dst_release(dst_orig);
3137 } else {
3138 /* Flow passes untransformed */
3139 dst_release(dst);
3140 dst = dst_orig;
3141 }
3142 ok:
3143 xfrm_pols_put(pols, drop_pols);
3144 if (dst && dst->xfrm &&
3145 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3146 dst->flags |= DST_XFRM_TUNNEL;
3147 return dst;
3148
3149 nopol:
3150 if (!(flags & XFRM_LOOKUP_ICMP)) {
3151 dst = dst_orig;
3152 goto ok;
3153 }
3154 err = -ENOENT;
3155 error:
3156 dst_release(dst);
3157 dropdst:
3158 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3159 dst_release(dst_orig);
3160 xfrm_pols_put(pols, drop_pols);
3161 return ERR_PTR(err);
3162 }
3163 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3164
3165 /* Main function: finds/creates a bundle for given flow.
3166 *
3167 * At the moment we eat a raw IP route. Mostly to speed up lookups
3168 * on interfaces with disabled IPsec.
3169 */
3170 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3171 const struct flowi *fl, const struct sock *sk,
3172 int flags)
3173 {
3174 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3175 }
3176 EXPORT_SYMBOL(xfrm_lookup);
3177
3178 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3179 * Otherwise we may send out blackholed packets.
3180 */
3181 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3182 const struct flowi *fl,
3183 const struct sock *sk, int flags)
3184 {
3185 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3186 flags | XFRM_LOOKUP_QUEUE |
3187 XFRM_LOOKUP_KEEP_DST_REF);
3188
3189 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
3190 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3191
3192 if (IS_ERR(dst))
3193 dst_release(dst_orig);
3194
3195 return dst;
3196 }
3197 EXPORT_SYMBOL(xfrm_lookup_route);
3198
3199 static inline int
3200 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3201 {
3202 struct sec_path *sp = skb_sec_path(skb);
3203 struct xfrm_state *x;
3204
3205 if (!sp || idx < 0 || idx >= sp->len)
3206 return 0;
3207 x = sp->xvec[idx];
3208 if (!x->type->reject)
3209 return 0;
3210 return x->type->reject(x, skb, fl);
3211 }
3212
3213 /* When skb is transformed back to its "native" form, we have to
3214 * check policy restrictions. At the moment we make this in maximally
3215 * stupid way. Shame on me. :-) Of course, connected sockets must
3216 * have policy cached at them.
3217 */
3218
3219 static inline int
3220 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3221 unsigned short family)
3222 {
3223 if (xfrm_state_kern(x))
3224 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3225 return x->id.proto == tmpl->id.proto &&
3226 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3227 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3228 x->props.mode == tmpl->mode &&
3229 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3230 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3231 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3232 xfrm_state_addr_cmp(tmpl, x, family));
3233 }
3234
3235 /*
3236 * 0 or more than 0 is returned when validation is succeeded (either bypass
3237 * because of optional transport mode, or next index of the mathced secpath
3238 * state with the template.
3239 * -1 is returned when no matching template is found.
3240 * Otherwise "-2 - errored_index" is returned.
3241 */
3242 static inline int
3243 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3244 unsigned short family)
3245 {
3246 int idx = start;
3247
3248 if (tmpl->optional) {
3249 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3250 return start;
3251 } else
3252 start = -1;
3253 for (; idx < sp->len; idx++) {
3254 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
3255 return ++idx;
3256 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3257 if (start == -1)
3258 start = -2-idx;
3259 break;
3260 }
3261 }
3262 return start;
3263 }
3264
3265 static void
3266 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3267 {
3268 const struct iphdr *iph = ip_hdr(skb);
3269 int ihl = iph->ihl;
3270 u8 *xprth = skb_network_header(skb) + ihl * 4;
3271 struct flowi4 *fl4 = &fl->u.ip4;
3272 int oif = 0;
3273
3274 if (skb_dst(skb) && skb_dst(skb)->dev)
3275 oif = skb_dst(skb)->dev->ifindex;
3276
3277 memset(fl4, 0, sizeof(struct flowi4));
3278 fl4->flowi4_mark = skb->mark;
3279 fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3280
3281 fl4->flowi4_proto = iph->protocol;
3282 fl4->daddr = reverse ? iph->saddr : iph->daddr;
3283 fl4->saddr = reverse ? iph->daddr : iph->saddr;
3284 fl4->flowi4_tos = iph->tos;
3285
3286 if (!ip_is_fragment(iph)) {
3287 switch (iph->protocol) {
3288 case IPPROTO_UDP:
3289 case IPPROTO_UDPLITE:
3290 case IPPROTO_TCP:
3291 case IPPROTO_SCTP:
3292 case IPPROTO_DCCP:
3293 if (xprth + 4 < skb->data ||
3294 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3295 __be16 *ports;
3296
3297 xprth = skb_network_header(skb) + ihl * 4;
3298 ports = (__be16 *)xprth;
3299
3300 fl4->fl4_sport = ports[!!reverse];
3301 fl4->fl4_dport = ports[!reverse];
3302 }
3303 break;
3304 case IPPROTO_ICMP:
3305 if (xprth + 2 < skb->data ||
3306 pskb_may_pull(skb, xprth + 2 - skb->data)) {
3307 u8 *icmp;
3308
3309 xprth = skb_network_header(skb) + ihl * 4;
3310 icmp = xprth;
3311
3312 fl4->fl4_icmp_type = icmp[0];
3313 fl4->fl4_icmp_code = icmp[1];
3314 }
3315 break;
3316 case IPPROTO_ESP:
3317 if (xprth + 4 < skb->data ||
3318 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3319 __be32 *ehdr;
3320
3321 xprth = skb_network_header(skb) + ihl * 4;
3322 ehdr = (__be32 *)xprth;
3323
3324 fl4->fl4_ipsec_spi = ehdr[0];
3325 }
3326 break;
3327 case IPPROTO_AH:
3328 if (xprth + 8 < skb->data ||
3329 pskb_may_pull(skb, xprth + 8 - skb->data)) {
3330 __be32 *ah_hdr;
3331
3332 xprth = skb_network_header(skb) + ihl * 4;
3333 ah_hdr = (__be32 *)xprth;
3334
3335 fl4->fl4_ipsec_spi = ah_hdr[1];
3336 }
3337 break;
3338 case IPPROTO_COMP:
3339 if (xprth + 4 < skb->data ||
3340 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3341 __be16 *ipcomp_hdr;
3342
3343 xprth = skb_network_header(skb) + ihl * 4;
3344 ipcomp_hdr = (__be16 *)xprth;
3345
3346 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
3347 }
3348 break;
3349 case IPPROTO_GRE:
3350 if (xprth + 12 < skb->data ||
3351 pskb_may_pull(skb, xprth + 12 - skb->data)) {
3352 __be16 *greflags;
3353 __be32 *gre_hdr;
3354
3355 xprth = skb_network_header(skb) + ihl * 4;
3356 greflags = (__be16 *)xprth;
3357 gre_hdr = (__be32 *)xprth;
3358
3359 if (greflags[0] & GRE_KEY) {
3360 if (greflags[0] & GRE_CSUM)
3361 gre_hdr++;
3362 fl4->fl4_gre_key = gre_hdr[1];
3363 }
3364 }
3365 break;
3366 default:
3367 fl4->fl4_ipsec_spi = 0;
3368 break;
3369 }
3370 }
3371 }
3372
3373 #if IS_ENABLED(CONFIG_IPV6)
3374 static void
3375 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3376 {
3377 struct flowi6 *fl6 = &fl->u.ip6;
3378 int onlyproto = 0;
3379 const struct ipv6hdr *hdr = ipv6_hdr(skb);
3380 u32 offset = sizeof(*hdr);
3381 struct ipv6_opt_hdr *exthdr;
3382 const unsigned char *nh = skb_network_header(skb);
3383 u16 nhoff = IP6CB(skb)->nhoff;
3384 int oif = 0;
3385 u8 nexthdr;
3386
3387 if (!nhoff)
3388 nhoff = offsetof(struct ipv6hdr, nexthdr);
3389
3390 nexthdr = nh[nhoff];
3391
3392 if (skb_dst(skb) && skb_dst(skb)->dev)
3393 oif = skb_dst(skb)->dev->ifindex;
3394
3395 memset(fl6, 0, sizeof(struct flowi6));
3396 fl6->flowi6_mark = skb->mark;
3397 fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3398
3399 fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3400 fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3401
3402 while (nh + offset + sizeof(*exthdr) < skb->data ||
3403 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3404 nh = skb_network_header(skb);
3405 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3406
3407 switch (nexthdr) {
3408 case NEXTHDR_FRAGMENT:
3409 onlyproto = 1;
3410 /* fall through */
3411 case NEXTHDR_ROUTING:
3412 case NEXTHDR_HOP:
3413 case NEXTHDR_DEST:
3414 offset += ipv6_optlen(exthdr);
3415 nexthdr = exthdr->nexthdr;
3416 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3417 break;
3418 case IPPROTO_UDP:
3419 case IPPROTO_UDPLITE:
3420 case IPPROTO_TCP:
3421 case IPPROTO_SCTP:
3422 case IPPROTO_DCCP:
3423 if (!onlyproto && (nh + offset + 4 < skb->data ||
3424 pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3425 __be16 *ports;
3426
3427 nh = skb_network_header(skb);
3428 ports = (__be16 *)(nh + offset);
3429 fl6->fl6_sport = ports[!!reverse];
3430 fl6->fl6_dport = ports[!reverse];
3431 }
3432 fl6->flowi6_proto = nexthdr;
3433 return;
3434 case IPPROTO_ICMPV6:
3435 if (!onlyproto && (nh + offset + 2 < skb->data ||
3436 pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3437 u8 *icmp;
3438
3439 nh = skb_network_header(skb);
3440 icmp = (u8 *)(nh + offset);
3441 fl6->fl6_icmp_type = icmp[0];
3442 fl6->fl6_icmp_code = icmp[1];
3443 }
3444 fl6->flowi6_proto = nexthdr;
3445 return;
3446 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3447 case IPPROTO_MH:
3448 offset += ipv6_optlen(exthdr);
3449 if (!onlyproto && (nh + offset + 3 < skb->data ||
3450 pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3451 struct ip6_mh *mh;
3452
3453 nh = skb_network_header(skb);
3454 mh = (struct ip6_mh *)(nh + offset);
3455 fl6->fl6_mh_type = mh->ip6mh_type;
3456 }
3457 fl6->flowi6_proto = nexthdr;
3458 return;
3459 #endif
3460 /* XXX Why are there these headers? */
3461 case IPPROTO_AH:
3462 case IPPROTO_ESP:
3463 case IPPROTO_COMP:
3464 default:
3465 fl6->fl6_ipsec_spi = 0;
3466 fl6->flowi6_proto = nexthdr;
3467 return;
3468 }
3469 }
3470 }
3471 #endif
3472
3473 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3474 unsigned int family, int reverse)
3475 {
3476 switch (family) {
3477 case AF_INET:
3478 decode_session4(skb, fl, reverse);
3479 break;
3480 #if IS_ENABLED(CONFIG_IPV6)
3481 case AF_INET6:
3482 decode_session6(skb, fl, reverse);
3483 break;
3484 #endif
3485 default:
3486 return -EAFNOSUPPORT;
3487 }
3488
3489 return security_xfrm_decode_session(skb, &fl->flowi_secid);
3490 }
3491 EXPORT_SYMBOL(__xfrm_decode_session);
3492
3493 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3494 {
3495 for (; k < sp->len; k++) {
3496 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3497 *idxp = k;
3498 return 1;
3499 }
3500 }
3501
3502 return 0;
3503 }
3504
3505 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3506 unsigned short family)
3507 {
3508 struct net *net = dev_net(skb->dev);
3509 struct xfrm_policy *pol;
3510 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3511 int npols = 0;
3512 int xfrm_nr;
3513 int pi;
3514 int reverse;
3515 struct flowi fl;
3516 int xerr_idx = -1;
3517 const struct xfrm_if_cb *ifcb;
3518 struct sec_path *sp;
3519 struct xfrm_if *xi;
3520 u32 if_id = 0;
3521
3522 rcu_read_lock();
3523 ifcb = xfrm_if_get_cb();
3524
3525 if (ifcb) {
3526 xi = ifcb->decode_session(skb, family);
3527 if (xi) {
3528 if_id = xi->p.if_id;
3529 net = xi->net;
3530 }
3531 }
3532 rcu_read_unlock();
3533
3534 reverse = dir & ~XFRM_POLICY_MASK;
3535 dir &= XFRM_POLICY_MASK;
3536
3537 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3538 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3539 return 0;
3540 }
3541
3542 nf_nat_decode_session(skb, &fl, family);
3543
3544 /* First, check used SA against their selectors. */
3545 sp = skb_sec_path(skb);
3546 if (sp) {
3547 int i;
3548
3549 for (i = sp->len - 1; i >= 0; i--) {
3550 struct xfrm_state *x = sp->xvec[i];
3551 if (!xfrm_selector_match(&x->sel, &fl, family)) {
3552 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3553 return 0;
3554 }
3555 }
3556 }
3557
3558 pol = NULL;
3559 sk = sk_to_full_sk(sk);
3560 if (sk && sk->sk_policy[dir]) {
3561 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3562 if (IS_ERR(pol)) {
3563 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3564 return 0;
3565 }
3566 }
3567
3568 if (!pol)
3569 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3570
3571 if (IS_ERR(pol)) {
3572 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3573 return 0;
3574 }
3575
3576 if (!pol) {
3577 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3578 xfrm_secpath_reject(xerr_idx, skb, &fl);
3579 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3580 return 0;
3581 }
3582 return 1;
3583 }
3584
3585 pol->curlft.use_time = ktime_get_real_seconds();
3586
3587 pols[0] = pol;
3588 npols++;
3589 #ifdef CONFIG_XFRM_SUB_POLICY
3590 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3591 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3592 &fl, family,
3593 XFRM_POLICY_IN, if_id);
3594 if (pols[1]) {
3595 if (IS_ERR(pols[1])) {
3596 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3597 return 0;
3598 }
3599 pols[1]->curlft.use_time = ktime_get_real_seconds();
3600 npols++;
3601 }
3602 }
3603 #endif
3604
3605 if (pol->action == XFRM_POLICY_ALLOW) {
3606 static struct sec_path dummy;
3607 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3608 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3609 struct xfrm_tmpl **tpp = tp;
3610 int ti = 0;
3611 int i, k;
3612
3613 sp = skb_sec_path(skb);
3614 if (!sp)
3615 sp = &dummy;
3616
3617 for (pi = 0; pi < npols; pi++) {
3618 if (pols[pi] != pol &&
3619 pols[pi]->action != XFRM_POLICY_ALLOW) {
3620 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3621 goto reject;
3622 }
3623 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3624 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3625 goto reject_error;
3626 }
3627 for (i = 0; i < pols[pi]->xfrm_nr; i++)
3628 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3629 }
3630 xfrm_nr = ti;
3631 if (npols > 1) {
3632 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3633 tpp = stp;
3634 }
3635
3636 /* For each tunnel xfrm, find the first matching tmpl.
3637 * For each tmpl before that, find corresponding xfrm.
3638 * Order is _important_. Later we will implement
3639 * some barriers, but at the moment barriers
3640 * are implied between each two transformations.
3641 */
3642 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3643 k = xfrm_policy_ok(tpp[i], sp, k, family);
3644 if (k < 0) {
3645 if (k < -1)
3646 /* "-2 - errored_index" returned */
3647 xerr_idx = -(2+k);
3648 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3649 goto reject;
3650 }
3651 }
3652
3653 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3654 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3655 goto reject;
3656 }
3657
3658 xfrm_pols_put(pols, npols);
3659 return 1;
3660 }
3661 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3662
3663 reject:
3664 xfrm_secpath_reject(xerr_idx, skb, &fl);
3665 reject_error:
3666 xfrm_pols_put(pols, npols);
3667 return 0;
3668 }
3669 EXPORT_SYMBOL(__xfrm_policy_check);
3670
3671 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3672 {
3673 struct net *net = dev_net(skb->dev);
3674 struct flowi fl;
3675 struct dst_entry *dst;
3676 int res = 1;
3677
3678 if (xfrm_decode_session(skb, &fl, family) < 0) {
3679 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3680 return 0;
3681 }
3682
3683 skb_dst_force(skb);
3684 if (!skb_dst(skb)) {
3685 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3686 return 0;
3687 }
3688
3689 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3690 if (IS_ERR(dst)) {
3691 res = 0;
3692 dst = NULL;
3693 }
3694 skb_dst_set(skb, dst);
3695 return res;
3696 }
3697 EXPORT_SYMBOL(__xfrm_route_forward);
3698
3699 /* Optimize later using cookies and generation ids. */
3700
3701 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3702 {
3703 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3704 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3705 * get validated by dst_ops->check on every use. We do this
3706 * because when a normal route referenced by an XFRM dst is
3707 * obsoleted we do not go looking around for all parent
3708 * referencing XFRM dsts so that we can invalidate them. It
3709 * is just too much work. Instead we make the checks here on
3710 * every use. For example:
3711 *
3712 * XFRM dst A --> IPv4 dst X
3713 *
3714 * X is the "xdst->route" of A (X is also the "dst->path" of A
3715 * in this example). If X is marked obsolete, "A" will not
3716 * notice. That's what we are validating here via the
3717 * stale_bundle() check.
3718 *
3719 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3720 * be marked on it.
3721 * This will force stale_bundle() to fail on any xdst bundle with
3722 * this dst linked in it.
3723 */
3724 if (dst->obsolete < 0 && !stale_bundle(dst))
3725 return dst;
3726
3727 return NULL;
3728 }
3729
3730 static int stale_bundle(struct dst_entry *dst)
3731 {
3732 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3733 }
3734
3735 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3736 {
3737 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3738 dst->dev = dev_net(dev)->loopback_dev;
3739 dev_hold(dst->dev);
3740 dev_put(dev);
3741 }
3742 }
3743 EXPORT_SYMBOL(xfrm_dst_ifdown);
3744
3745 static void xfrm_link_failure(struct sk_buff *skb)
3746 {
3747 /* Impossible. Such dst must be popped before reaches point of failure. */
3748 }
3749
3750 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3751 {
3752 if (dst) {
3753 if (dst->obsolete) {
3754 dst_release(dst);
3755 dst = NULL;
3756 }
3757 }
3758 return dst;
3759 }
3760
3761 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3762 {
3763 while (nr--) {
3764 struct xfrm_dst *xdst = bundle[nr];
3765 u32 pmtu, route_mtu_cached;
3766 struct dst_entry *dst;
3767
3768 dst = &xdst->u.dst;
3769 pmtu = dst_mtu(xfrm_dst_child(dst));
3770 xdst->child_mtu_cached = pmtu;
3771
3772 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3773
3774 route_mtu_cached = dst_mtu(xdst->route);
3775 xdst->route_mtu_cached = route_mtu_cached;
3776
3777 if (pmtu > route_mtu_cached)
3778 pmtu = route_mtu_cached;
3779
3780 dst_metric_set(dst, RTAX_MTU, pmtu);
3781 }
3782 }
3783
3784 /* Check that the bundle accepts the flow and its components are
3785 * still valid.
3786 */
3787
3788 static int xfrm_bundle_ok(struct xfrm_dst *first)
3789 {
3790 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3791 struct dst_entry *dst = &first->u.dst;
3792 struct xfrm_dst *xdst;
3793 int start_from, nr;
3794 u32 mtu;
3795
3796 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3797 (dst->dev && !netif_running(dst->dev)))
3798 return 0;
3799
3800 if (dst->flags & DST_XFRM_QUEUE)
3801 return 1;
3802
3803 start_from = nr = 0;
3804 do {
3805 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3806
3807 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3808 return 0;
3809 if (xdst->xfrm_genid != dst->xfrm->genid)
3810 return 0;
3811 if (xdst->num_pols > 0 &&
3812 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3813 return 0;
3814
3815 bundle[nr++] = xdst;
3816
3817 mtu = dst_mtu(xfrm_dst_child(dst));
3818 if (xdst->child_mtu_cached != mtu) {
3819 start_from = nr;
3820 xdst->child_mtu_cached = mtu;
3821 }
3822
3823 if (!dst_check(xdst->route, xdst->route_cookie))
3824 return 0;
3825 mtu = dst_mtu(xdst->route);
3826 if (xdst->route_mtu_cached != mtu) {
3827 start_from = nr;
3828 xdst->route_mtu_cached = mtu;
3829 }
3830
3831 dst = xfrm_dst_child(dst);
3832 } while (dst->xfrm);
3833
3834 if (likely(!start_from))
3835 return 1;
3836
3837 xdst = bundle[start_from - 1];
3838 mtu = xdst->child_mtu_cached;
3839 while (start_from--) {
3840 dst = &xdst->u.dst;
3841
3842 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3843 if (mtu > xdst->route_mtu_cached)
3844 mtu = xdst->route_mtu_cached;
3845 dst_metric_set(dst, RTAX_MTU, mtu);
3846 if (!start_from)
3847 break;
3848
3849 xdst = bundle[start_from - 1];
3850 xdst->child_mtu_cached = mtu;
3851 }
3852
3853 return 1;
3854 }
3855
3856 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3857 {
3858 return dst_metric_advmss(xfrm_dst_path(dst));
3859 }
3860
3861 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3862 {
3863 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3864
3865 return mtu ? : dst_mtu(xfrm_dst_path(dst));
3866 }
3867
3868 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3869 const void *daddr)
3870 {
3871 while (dst->xfrm) {
3872 const struct xfrm_state *xfrm = dst->xfrm;
3873
3874 dst = xfrm_dst_child(dst);
3875
3876 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3877 continue;
3878 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3879 daddr = xfrm->coaddr;
3880 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3881 daddr = &xfrm->id.daddr;
3882 }
3883 return daddr;
3884 }
3885
3886 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3887 struct sk_buff *skb,
3888 const void *daddr)
3889 {
3890 const struct dst_entry *path = xfrm_dst_path(dst);
3891
3892 if (!skb)
3893 daddr = xfrm_get_dst_nexthop(dst, daddr);
3894 return path->ops->neigh_lookup(path, skb, daddr);
3895 }
3896
3897 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3898 {
3899 const struct dst_entry *path = xfrm_dst_path(dst);
3900
3901 daddr = xfrm_get_dst_nexthop(dst, daddr);
3902 path->ops->confirm_neigh(path, daddr);
3903 }
3904
3905 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3906 {
3907 int err = 0;
3908
3909 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3910 return -EAFNOSUPPORT;
3911
3912 spin_lock(&xfrm_policy_afinfo_lock);
3913 if (unlikely(xfrm_policy_afinfo[family] != NULL))
3914 err = -EEXIST;
3915 else {
3916 struct dst_ops *dst_ops = afinfo->dst_ops;
3917 if (likely(dst_ops->kmem_cachep == NULL))
3918 dst_ops->kmem_cachep = xfrm_dst_cache;
3919 if (likely(dst_ops->check == NULL))
3920 dst_ops->check = xfrm_dst_check;
3921 if (likely(dst_ops->default_advmss == NULL))
3922 dst_ops->default_advmss = xfrm_default_advmss;
3923 if (likely(dst_ops->mtu == NULL))
3924 dst_ops->mtu = xfrm_mtu;
3925 if (likely(dst_ops->negative_advice == NULL))
3926 dst_ops->negative_advice = xfrm_negative_advice;
3927 if (likely(dst_ops->link_failure == NULL))
3928 dst_ops->link_failure = xfrm_link_failure;
3929 if (likely(dst_ops->neigh_lookup == NULL))
3930 dst_ops->neigh_lookup = xfrm_neigh_lookup;
3931 if (likely(!dst_ops->confirm_neigh))
3932 dst_ops->confirm_neigh = xfrm_confirm_neigh;
3933 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
3934 }
3935 spin_unlock(&xfrm_policy_afinfo_lock);
3936
3937 return err;
3938 }
3939 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
3940
3941 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
3942 {
3943 struct dst_ops *dst_ops = afinfo->dst_ops;
3944 int i;
3945
3946 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
3947 if (xfrm_policy_afinfo[i] != afinfo)
3948 continue;
3949 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
3950 break;
3951 }
3952
3953 synchronize_rcu();
3954
3955 dst_ops->kmem_cachep = NULL;
3956 dst_ops->check = NULL;
3957 dst_ops->negative_advice = NULL;
3958 dst_ops->link_failure = NULL;
3959 }
3960 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
3961
3962 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
3963 {
3964 spin_lock(&xfrm_if_cb_lock);
3965 rcu_assign_pointer(xfrm_if_cb, ifcb);
3966 spin_unlock(&xfrm_if_cb_lock);
3967 }
3968 EXPORT_SYMBOL(xfrm_if_register_cb);
3969
3970 void xfrm_if_unregister_cb(void)
3971 {
3972 RCU_INIT_POINTER(xfrm_if_cb, NULL);
3973 synchronize_rcu();
3974 }
3975 EXPORT_SYMBOL(xfrm_if_unregister_cb);
3976
3977 #ifdef CONFIG_XFRM_STATISTICS
3978 static int __net_init xfrm_statistics_init(struct net *net)
3979 {
3980 int rv;
3981 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
3982 if (!net->mib.xfrm_statistics)
3983 return -ENOMEM;
3984 rv = xfrm_proc_init(net);
3985 if (rv < 0)
3986 free_percpu(net->mib.xfrm_statistics);
3987 return rv;
3988 }
3989
3990 static void xfrm_statistics_fini(struct net *net)
3991 {
3992 xfrm_proc_fini(net);
3993 free_percpu(net->mib.xfrm_statistics);
3994 }
3995 #else
3996 static int __net_init xfrm_statistics_init(struct net *net)
3997 {
3998 return 0;
3999 }
4000
4001 static void xfrm_statistics_fini(struct net *net)
4002 {
4003 }
4004 #endif
4005
4006 static int __net_init xfrm_policy_init(struct net *net)
4007 {
4008 unsigned int hmask, sz;
4009 int dir, err;
4010
4011 if (net_eq(net, &init_net)) {
4012 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4013 sizeof(struct xfrm_dst),
4014 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4015 NULL);
4016 err = rhashtable_init(&xfrm_policy_inexact_table,
4017 &xfrm_pol_inexact_params);
4018 BUG_ON(err);
4019 }
4020
4021 hmask = 8 - 1;
4022 sz = (hmask+1) * sizeof(struct hlist_head);
4023
4024 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4025 if (!net->xfrm.policy_byidx)
4026 goto out_byidx;
4027 net->xfrm.policy_idx_hmask = hmask;
4028
4029 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4030 struct xfrm_policy_hash *htab;
4031
4032 net->xfrm.policy_count[dir] = 0;
4033 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4034 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4035
4036 htab = &net->xfrm.policy_bydst[dir];
4037 htab->table = xfrm_hash_alloc(sz);
4038 if (!htab->table)
4039 goto out_bydst;
4040 htab->hmask = hmask;
4041 htab->dbits4 = 32;
4042 htab->sbits4 = 32;
4043 htab->dbits6 = 128;
4044 htab->sbits6 = 128;
4045 }
4046 net->xfrm.policy_hthresh.lbits4 = 32;
4047 net->xfrm.policy_hthresh.rbits4 = 32;
4048 net->xfrm.policy_hthresh.lbits6 = 128;
4049 net->xfrm.policy_hthresh.rbits6 = 128;
4050
4051 seqlock_init(&net->xfrm.policy_hthresh.lock);
4052
4053 INIT_LIST_HEAD(&net->xfrm.policy_all);
4054 INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4055 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4056 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4057 return 0;
4058
4059 out_bydst:
4060 for (dir--; dir >= 0; dir--) {
4061 struct xfrm_policy_hash *htab;
4062
4063 htab = &net->xfrm.policy_bydst[dir];
4064 xfrm_hash_free(htab->table, sz);
4065 }
4066 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4067 out_byidx:
4068 return -ENOMEM;
4069 }
4070
4071 static void xfrm_policy_fini(struct net *net)
4072 {
4073 struct xfrm_pol_inexact_bin *b, *t;
4074 unsigned int sz;
4075 int dir;
4076
4077 flush_work(&net->xfrm.policy_hash_work);
4078 #ifdef CONFIG_XFRM_SUB_POLICY
4079 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4080 #endif
4081 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4082
4083 WARN_ON(!list_empty(&net->xfrm.policy_all));
4084
4085 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4086 struct xfrm_policy_hash *htab;
4087
4088 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4089
4090 htab = &net->xfrm.policy_bydst[dir];
4091 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4092 WARN_ON(!hlist_empty(htab->table));
4093 xfrm_hash_free(htab->table, sz);
4094 }
4095
4096 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4097 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4098 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4099
4100 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4101 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4102 __xfrm_policy_inexact_prune_bin(b, true);
4103 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4104 }
4105
4106 static int __net_init xfrm_net_init(struct net *net)
4107 {
4108 int rv;
4109
4110 /* Initialize the per-net locks here */
4111 spin_lock_init(&net->xfrm.xfrm_state_lock);
4112 spin_lock_init(&net->xfrm.xfrm_policy_lock);
4113 mutex_init(&net->xfrm.xfrm_cfg_mutex);
4114
4115 rv = xfrm_statistics_init(net);
4116 if (rv < 0)
4117 goto out_statistics;
4118 rv = xfrm_state_init(net);
4119 if (rv < 0)
4120 goto out_state;
4121 rv = xfrm_policy_init(net);
4122 if (rv < 0)
4123 goto out_policy;
4124 rv = xfrm_sysctl_init(net);
4125 if (rv < 0)
4126 goto out_sysctl;
4127
4128 return 0;
4129
4130 out_sysctl:
4131 xfrm_policy_fini(net);
4132 out_policy:
4133 xfrm_state_fini(net);
4134 out_state:
4135 xfrm_statistics_fini(net);
4136 out_statistics:
4137 return rv;
4138 }
4139
4140 static void __net_exit xfrm_net_exit(struct net *net)
4141 {
4142 xfrm_sysctl_fini(net);
4143 xfrm_policy_fini(net);
4144 xfrm_state_fini(net);
4145 xfrm_statistics_fini(net);
4146 }
4147
4148 static struct pernet_operations __net_initdata xfrm_net_ops = {
4149 .init = xfrm_net_init,
4150 .exit = xfrm_net_exit,
4151 };
4152
4153 void __init xfrm_init(void)
4154 {
4155 register_pernet_subsys(&xfrm_net_ops);
4156 xfrm_dev_init();
4157 seqcount_init(&xfrm_policy_hash_generation);
4158 xfrm_input_init();
4159
4160 RCU_INIT_POINTER(xfrm_if_cb, NULL);
4161 synchronize_rcu();
4162 }
4163
4164 #ifdef CONFIG_AUDITSYSCALL
4165 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4166 struct audit_buffer *audit_buf)
4167 {
4168 struct xfrm_sec_ctx *ctx = xp->security;
4169 struct xfrm_selector *sel = &xp->selector;
4170
4171 if (ctx)
4172 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4173 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4174
4175 switch (sel->family) {
4176 case AF_INET:
4177 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4178 if (sel->prefixlen_s != 32)
4179 audit_log_format(audit_buf, " src_prefixlen=%d",
4180 sel->prefixlen_s);
4181 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4182 if (sel->prefixlen_d != 32)
4183 audit_log_format(audit_buf, " dst_prefixlen=%d",
4184 sel->prefixlen_d);
4185 break;
4186 case AF_INET6:
4187 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4188 if (sel->prefixlen_s != 128)
4189 audit_log_format(audit_buf, " src_prefixlen=%d",
4190 sel->prefixlen_s);
4191 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4192 if (sel->prefixlen_d != 128)
4193 audit_log_format(audit_buf, " dst_prefixlen=%d",
4194 sel->prefixlen_d);
4195 break;
4196 }
4197 }
4198
4199 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4200 {
4201 struct audit_buffer *audit_buf;
4202
4203 audit_buf = xfrm_audit_start("SPD-add");
4204 if (audit_buf == NULL)
4205 return;
4206 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4207 audit_log_format(audit_buf, " res=%u", result);
4208 xfrm_audit_common_policyinfo(xp, audit_buf);
4209 audit_log_end(audit_buf);
4210 }
4211 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4212
4213 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4214 bool task_valid)
4215 {
4216 struct audit_buffer *audit_buf;
4217
4218 audit_buf = xfrm_audit_start("SPD-delete");
4219 if (audit_buf == NULL)
4220 return;
4221 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4222 audit_log_format(audit_buf, " res=%u", result);
4223 xfrm_audit_common_policyinfo(xp, audit_buf);
4224 audit_log_end(audit_buf);
4225 }
4226 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4227 #endif
4228
4229 #ifdef CONFIG_XFRM_MIGRATE
4230 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4231 const struct xfrm_selector *sel_tgt)
4232 {
4233 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4234 if (sel_tgt->family == sel_cmp->family &&
4235 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4236 sel_cmp->family) &&
4237 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4238 sel_cmp->family) &&
4239 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4240 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4241 return true;
4242 }
4243 } else {
4244 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4245 return true;
4246 }
4247 }
4248 return false;
4249 }
4250
4251 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4252 u8 dir, u8 type, struct net *net)
4253 {
4254 struct xfrm_policy *pol, *ret = NULL;
4255 struct hlist_head *chain;
4256 u32 priority = ~0U;
4257
4258 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4259 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4260 hlist_for_each_entry(pol, chain, bydst) {
4261 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4262 pol->type == type) {
4263 ret = pol;
4264 priority = ret->priority;
4265 break;
4266 }
4267 }
4268 chain = &net->xfrm.policy_inexact[dir];
4269 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4270 if ((pol->priority >= priority) && ret)
4271 break;
4272
4273 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4274 pol->type == type) {
4275 ret = pol;
4276 break;
4277 }
4278 }
4279
4280 xfrm_pol_hold(ret);
4281
4282 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4283
4284 return ret;
4285 }
4286
4287 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4288 {
4289 int match = 0;
4290
4291 if (t->mode == m->mode && t->id.proto == m->proto &&
4292 (m->reqid == 0 || t->reqid == m->reqid)) {
4293 switch (t->mode) {
4294 case XFRM_MODE_TUNNEL:
4295 case XFRM_MODE_BEET:
4296 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4297 m->old_family) &&
4298 xfrm_addr_equal(&t->saddr, &m->old_saddr,
4299 m->old_family)) {
4300 match = 1;
4301 }
4302 break;
4303 case XFRM_MODE_TRANSPORT:
4304 /* in case of transport mode, template does not store
4305 any IP addresses, hence we just compare mode and
4306 protocol */
4307 match = 1;
4308 break;
4309 default:
4310 break;
4311 }
4312 }
4313 return match;
4314 }
4315
4316 /* update endpoint address(es) of template(s) */
4317 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4318 struct xfrm_migrate *m, int num_migrate)
4319 {
4320 struct xfrm_migrate *mp;
4321 int i, j, n = 0;
4322
4323 write_lock_bh(&pol->lock);
4324 if (unlikely(pol->walk.dead)) {
4325 /* target policy has been deleted */
4326 write_unlock_bh(&pol->lock);
4327 return -ENOENT;
4328 }
4329
4330 for (i = 0; i < pol->xfrm_nr; i++) {
4331 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4332 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4333 continue;
4334 n++;
4335 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4336 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4337 continue;
4338 /* update endpoints */
4339 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4340 sizeof(pol->xfrm_vec[i].id.daddr));
4341 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4342 sizeof(pol->xfrm_vec[i].saddr));
4343 pol->xfrm_vec[i].encap_family = mp->new_family;
4344 /* flush bundles */
4345 atomic_inc(&pol->genid);
4346 }
4347 }
4348
4349 write_unlock_bh(&pol->lock);
4350
4351 if (!n)
4352 return -ENODATA;
4353
4354 return 0;
4355 }
4356
4357 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
4358 {
4359 int i, j;
4360
4361 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
4362 return -EINVAL;
4363
4364 for (i = 0; i < num_migrate; i++) {
4365 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4366 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
4367 return -EINVAL;
4368
4369 /* check if there is any duplicated entry */
4370 for (j = i + 1; j < num_migrate; j++) {
4371 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4372 sizeof(m[i].old_daddr)) &&
4373 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4374 sizeof(m[i].old_saddr)) &&
4375 m[i].proto == m[j].proto &&
4376 m[i].mode == m[j].mode &&
4377 m[i].reqid == m[j].reqid &&
4378 m[i].old_family == m[j].old_family)
4379 return -EINVAL;
4380 }
4381 }
4382
4383 return 0;
4384 }
4385
4386 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4387 struct xfrm_migrate *m, int num_migrate,
4388 struct xfrm_kmaddress *k, struct net *net,
4389 struct xfrm_encap_tmpl *encap)
4390 {
4391 int i, err, nx_cur = 0, nx_new = 0;
4392 struct xfrm_policy *pol = NULL;
4393 struct xfrm_state *x, *xc;
4394 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4395 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4396 struct xfrm_migrate *mp;
4397
4398 /* Stage 0 - sanity checks */
4399 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
4400 goto out;
4401
4402 if (dir >= XFRM_POLICY_MAX) {
4403 err = -EINVAL;
4404 goto out;
4405 }
4406
4407 /* Stage 1 - find policy */
4408 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
4409 err = -ENOENT;
4410 goto out;
4411 }
4412
4413 /* Stage 2 - find and update state(s) */
4414 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4415 if ((x = xfrm_migrate_state_find(mp, net))) {
4416 x_cur[nx_cur] = x;
4417 nx_cur++;
4418 xc = xfrm_state_migrate(x, mp, encap);
4419 if (xc) {
4420 x_new[nx_new] = xc;
4421 nx_new++;
4422 } else {
4423 err = -ENODATA;
4424 goto restore_state;
4425 }
4426 }
4427 }
4428
4429 /* Stage 3 - update policy */
4430 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
4431 goto restore_state;
4432
4433 /* Stage 4 - delete old state(s) */
4434 if (nx_cur) {
4435 xfrm_states_put(x_cur, nx_cur);
4436 xfrm_states_delete(x_cur, nx_cur);
4437 }
4438
4439 /* Stage 5 - announce */
4440 km_migrate(sel, dir, type, m, num_migrate, k, encap);
4441
4442 xfrm_pol_put(pol);
4443
4444 return 0;
4445 out:
4446 return err;
4447
4448 restore_state:
4449 if (pol)
4450 xfrm_pol_put(pol);
4451 if (nx_cur)
4452 xfrm_states_put(x_cur, nx_cur);
4453 if (nx_new)
4454 xfrm_states_delete(x_new, nx_new);
4455
4456 return err;
4457 }
4458 EXPORT_SYMBOL(xfrm_migrate);
4459 #endif
connection oriented routing