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lockd: fix "list_add double add" caused by legacy signal interface
[linux/fpc-iii.git] / net / xfrm / xfrm_policy.c
blob9542975eb2f90dcb2bae894edeb9b418d04f252e
1 /*
2 * xfrm_policy.c
3 *
4 * Changes:
5 * Mitsuru KANDA @USAGI
6 * Kazunori MIYAZAWA @USAGI
7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8 * IPv6 support
9 * Kazunori MIYAZAWA @USAGI
10 * YOSHIFUJI Hideaki
11 * Split up af-specific portion
12 * Derek Atkins <derek@ihtfp.com> Add the post_input processor
13 *
14 */
15
16 #include <linux/err.h>
17 #include <linux/slab.h>
18 #include <linux/kmod.h>
19 #include <linux/list.h>
20 #include <linux/spinlock.h>
21 #include <linux/workqueue.h>
22 #include <linux/notifier.h>
23 #include <linux/netdevice.h>
24 #include <linux/netfilter.h>
25 #include <linux/module.h>
26 #include <linux/cache.h>
27 #include <linux/cpu.h>
28 #include <linux/audit.h>
29 #include <net/dst.h>
30 #include <net/flow.h>
31 #include <net/xfrm.h>
32 #include <net/ip.h>
33 #ifdef CONFIG_XFRM_STATISTICS
34 #include <net/snmp.h>
35 #endif
36
37 #include "xfrm_hash.h"
38
39 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
40 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
41 #define XFRM_MAX_QUEUE_LEN 100
42
43 struct xfrm_flo {
44 struct dst_entry *dst_orig;
45 u8 flags;
46 };
47
48 static DEFINE_PER_CPU(struct xfrm_dst *, xfrm_last_dst);
49 static struct work_struct *xfrm_pcpu_work __read_mostly;
50 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
51 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
52 __read_mostly;
53
54 static struct kmem_cache *xfrm_dst_cache __read_mostly;
55 static __read_mostly seqcount_t xfrm_policy_hash_generation;
56
57 static void xfrm_init_pmtu(struct dst_entry *dst);
58 static int stale_bundle(struct dst_entry *dst);
59 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
60 static void xfrm_policy_queue_process(struct timer_list *t);
61
62 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
63 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
64 int dir);
65
66 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
67 {
68 return refcount_inc_not_zero(&policy->refcnt);
69 }
70
71 static inline bool
72 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
73 {
74 const struct flowi4 *fl4 = &fl->u.ip4;
75
76 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
77 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
78 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
79 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
80 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
81 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
82 }
83
84 static inline bool
85 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
86 {
87 const struct flowi6 *fl6 = &fl->u.ip6;
88
89 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
90 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
91 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
92 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
93 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
94 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
95 }
96
97 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
98 unsigned short family)
99 {
100 switch (family) {
101 case AF_INET:
102 return __xfrm4_selector_match(sel, fl);
103 case AF_INET6:
104 return __xfrm6_selector_match(sel, fl);
105 }
106 return false;
107 }
108
109 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
110 {
111 const struct xfrm_policy_afinfo *afinfo;
112
113 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
114 return NULL;
115 rcu_read_lock();
116 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
117 if (unlikely(!afinfo))
118 rcu_read_unlock();
119 return afinfo;
120 }
121
122 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
123 const xfrm_address_t *saddr,
124 const xfrm_address_t *daddr,
125 int family, u32 mark)
126 {
127 const struct xfrm_policy_afinfo *afinfo;
128 struct dst_entry *dst;
129
130 afinfo = xfrm_policy_get_afinfo(family);
131 if (unlikely(afinfo == NULL))
132 return ERR_PTR(-EAFNOSUPPORT);
133
134 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
135
136 rcu_read_unlock();
137
138 return dst;
139 }
140 EXPORT_SYMBOL(__xfrm_dst_lookup);
141
142 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
143 int tos, int oif,
144 xfrm_address_t *prev_saddr,
145 xfrm_address_t *prev_daddr,
146 int family, u32 mark)
147 {
148 struct net *net = xs_net(x);
149 xfrm_address_t *saddr = &x->props.saddr;
150 xfrm_address_t *daddr = &x->id.daddr;
151 struct dst_entry *dst;
152
153 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
154 saddr = x->coaddr;
155 daddr = prev_daddr;
156 }
157 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
158 saddr = prev_saddr;
159 daddr = x->coaddr;
160 }
161
162 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
163
164 if (!IS_ERR(dst)) {
165 if (prev_saddr != saddr)
166 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
167 if (prev_daddr != daddr)
168 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
169 }
170
171 return dst;
172 }
173
174 static inline unsigned long make_jiffies(long secs)
175 {
176 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
177 return MAX_SCHEDULE_TIMEOUT-1;
178 else
179 return secs*HZ;
180 }
181
182 static void xfrm_policy_timer(struct timer_list *t)
183 {
184 struct xfrm_policy *xp = from_timer(xp, t, timer);
185 unsigned long now = get_seconds();
186 long next = LONG_MAX;
187 int warn = 0;
188 int dir;
189
190 read_lock(&xp->lock);
191
192 if (unlikely(xp->walk.dead))
193 goto out;
194
195 dir = xfrm_policy_id2dir(xp->index);
196
197 if (xp->lft.hard_add_expires_seconds) {
198 long tmo = xp->lft.hard_add_expires_seconds +
199 xp->curlft.add_time - now;
200 if (tmo <= 0)
201 goto expired;
202 if (tmo < next)
203 next = tmo;
204 }
205 if (xp->lft.hard_use_expires_seconds) {
206 long tmo = xp->lft.hard_use_expires_seconds +
207 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
208 if (tmo <= 0)
209 goto expired;
210 if (tmo < next)
211 next = tmo;
212 }
213 if (xp->lft.soft_add_expires_seconds) {
214 long tmo = xp->lft.soft_add_expires_seconds +
215 xp->curlft.add_time - now;
216 if (tmo <= 0) {
217 warn = 1;
218 tmo = XFRM_KM_TIMEOUT;
219 }
220 if (tmo < next)
221 next = tmo;
222 }
223 if (xp->lft.soft_use_expires_seconds) {
224 long tmo = xp->lft.soft_use_expires_seconds +
225 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
226 if (tmo <= 0) {
227 warn = 1;
228 tmo = XFRM_KM_TIMEOUT;
229 }
230 if (tmo < next)
231 next = tmo;
232 }
233
234 if (warn)
235 km_policy_expired(xp, dir, 0, 0);
236 if (next != LONG_MAX &&
237 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
238 xfrm_pol_hold(xp);
239
240 out:
241 read_unlock(&xp->lock);
242 xfrm_pol_put(xp);
243 return;
244
245 expired:
246 read_unlock(&xp->lock);
247 if (!xfrm_policy_delete(xp, dir))
248 km_policy_expired(xp, dir, 1, 0);
249 xfrm_pol_put(xp);
250 }
251
252 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
253 * SPD calls.
254 */
255
256 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
257 {
258 struct xfrm_policy *policy;
259
260 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
261
262 if (policy) {
263 write_pnet(&policy->xp_net, net);
264 INIT_LIST_HEAD(&policy->walk.all);
265 INIT_HLIST_NODE(&policy->bydst);
266 INIT_HLIST_NODE(&policy->byidx);
267 rwlock_init(&policy->lock);
268 refcount_set(&policy->refcnt, 1);
269 skb_queue_head_init(&policy->polq.hold_queue);
270 timer_setup(&policy->timer, xfrm_policy_timer, 0);
271 timer_setup(&policy->polq.hold_timer,
272 xfrm_policy_queue_process, 0);
273 }
274 return policy;
275 }
276 EXPORT_SYMBOL(xfrm_policy_alloc);
277
278 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
279 {
280 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
281
282 security_xfrm_policy_free(policy->security);
283 kfree(policy);
284 }
285
286 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
287
288 void xfrm_policy_destroy(struct xfrm_policy *policy)
289 {
290 BUG_ON(!policy->walk.dead);
291
292 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
293 BUG();
294
295 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
296 }
297 EXPORT_SYMBOL(xfrm_policy_destroy);
298
299 /* Rule must be locked. Release descendant resources, announce
300 * entry dead. The rule must be unlinked from lists to the moment.
301 */
302
303 static void xfrm_policy_kill(struct xfrm_policy *policy)
304 {
305 policy->walk.dead = 1;
306
307 atomic_inc(&policy->genid);
308
309 if (del_timer(&policy->polq.hold_timer))
310 xfrm_pol_put(policy);
311 skb_queue_purge(&policy->polq.hold_queue);
312
313 if (del_timer(&policy->timer))
314 xfrm_pol_put(policy);
315
316 xfrm_pol_put(policy);
317 }
318
319 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
320
321 static inline unsigned int idx_hash(struct net *net, u32 index)
322 {
323 return __idx_hash(index, net->xfrm.policy_idx_hmask);
324 }
325
326 /* calculate policy hash thresholds */
327 static void __get_hash_thresh(struct net *net,
328 unsigned short family, int dir,
329 u8 *dbits, u8 *sbits)
330 {
331 switch (family) {
332 case AF_INET:
333 *dbits = net->xfrm.policy_bydst[dir].dbits4;
334 *sbits = net->xfrm.policy_bydst[dir].sbits4;
335 break;
336
337 case AF_INET6:
338 *dbits = net->xfrm.policy_bydst[dir].dbits6;
339 *sbits = net->xfrm.policy_bydst[dir].sbits6;
340 break;
341
342 default:
343 *dbits = 0;
344 *sbits = 0;
345 }
346 }
347
348 static struct hlist_head *policy_hash_bysel(struct net *net,
349 const struct xfrm_selector *sel,
350 unsigned short family, int dir)
351 {
352 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
353 unsigned int hash;
354 u8 dbits;
355 u8 sbits;
356
357 __get_hash_thresh(net, family, dir, &dbits, &sbits);
358 hash = __sel_hash(sel, family, hmask, dbits, sbits);
359
360 if (hash == hmask + 1)
361 return &net->xfrm.policy_inexact[dir];
362
363 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
364 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
365 }
366
367 static struct hlist_head *policy_hash_direct(struct net *net,
368 const xfrm_address_t *daddr,
369 const xfrm_address_t *saddr,
370 unsigned short family, int dir)
371 {
372 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
373 unsigned int hash;
374 u8 dbits;
375 u8 sbits;
376
377 __get_hash_thresh(net, family, dir, &dbits, &sbits);
378 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
379
380 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
381 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
382 }
383
384 static void xfrm_dst_hash_transfer(struct net *net,
385 struct hlist_head *list,
386 struct hlist_head *ndsttable,
387 unsigned int nhashmask,
388 int dir)
389 {
390 struct hlist_node *tmp, *entry0 = NULL;
391 struct xfrm_policy *pol;
392 unsigned int h0 = 0;
393 u8 dbits;
394 u8 sbits;
395
396 redo:
397 hlist_for_each_entry_safe(pol, tmp, list, bydst) {
398 unsigned int h;
399
400 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
401 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
402 pol->family, nhashmask, dbits, sbits);
403 if (!entry0) {
404 hlist_del_rcu(&pol->bydst);
405 hlist_add_head_rcu(&pol->bydst, ndsttable + h);
406 h0 = h;
407 } else {
408 if (h != h0)
409 continue;
410 hlist_del_rcu(&pol->bydst);
411 hlist_add_behind_rcu(&pol->bydst, entry0);
412 }
413 entry0 = &pol->bydst;
414 }
415 if (!hlist_empty(list)) {
416 entry0 = NULL;
417 goto redo;
418 }
419 }
420
421 static void xfrm_idx_hash_transfer(struct hlist_head *list,
422 struct hlist_head *nidxtable,
423 unsigned int nhashmask)
424 {
425 struct hlist_node *tmp;
426 struct xfrm_policy *pol;
427
428 hlist_for_each_entry_safe(pol, tmp, list, byidx) {
429 unsigned int h;
430
431 h = __idx_hash(pol->index, nhashmask);
432 hlist_add_head(&pol->byidx, nidxtable+h);
433 }
434 }
435
436 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
437 {
438 return ((old_hmask + 1) << 1) - 1;
439 }
440
441 static void xfrm_bydst_resize(struct net *net, int dir)
442 {
443 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
444 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
445 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
446 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
447 struct hlist_head *odst;
448 int i;
449
450 if (!ndst)
451 return;
452
453 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
454 write_seqcount_begin(&xfrm_policy_hash_generation);
455
456 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
457 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
458
459 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
460 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
461
462 for (i = hmask; i >= 0; i--)
463 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
464
465 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
466 net->xfrm.policy_bydst[dir].hmask = nhashmask;
467
468 write_seqcount_end(&xfrm_policy_hash_generation);
469 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
470
471 synchronize_rcu();
472
473 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
474 }
475
476 static void xfrm_byidx_resize(struct net *net, int total)
477 {
478 unsigned int hmask = net->xfrm.policy_idx_hmask;
479 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
480 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
481 struct hlist_head *oidx = net->xfrm.policy_byidx;
482 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
483 int i;
484
485 if (!nidx)
486 return;
487
488 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
489
490 for (i = hmask; i >= 0; i--)
491 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
492
493 net->xfrm.policy_byidx = nidx;
494 net->xfrm.policy_idx_hmask = nhashmask;
495
496 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
497
498 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
499 }
500
501 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
502 {
503 unsigned int cnt = net->xfrm.policy_count[dir];
504 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
505
506 if (total)
507 *total += cnt;
508
509 if ((hmask + 1) < xfrm_policy_hashmax &&
510 cnt > hmask)
511 return 1;
512
513 return 0;
514 }
515
516 static inline int xfrm_byidx_should_resize(struct net *net, int total)
517 {
518 unsigned int hmask = net->xfrm.policy_idx_hmask;
519
520 if ((hmask + 1) < xfrm_policy_hashmax &&
521 total > hmask)
522 return 1;
523
524 return 0;
525 }
526
527 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
528 {
529 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
530 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
531 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
532 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
533 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
534 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
535 si->spdhcnt = net->xfrm.policy_idx_hmask;
536 si->spdhmcnt = xfrm_policy_hashmax;
537 }
538 EXPORT_SYMBOL(xfrm_spd_getinfo);
539
540 static DEFINE_MUTEX(hash_resize_mutex);
541 static void xfrm_hash_resize(struct work_struct *work)
542 {
543 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
544 int dir, total;
545
546 mutex_lock(&hash_resize_mutex);
547
548 total = 0;
549 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
550 if (xfrm_bydst_should_resize(net, dir, &total))
551 xfrm_bydst_resize(net, dir);
552 }
553 if (xfrm_byidx_should_resize(net, total))
554 xfrm_byidx_resize(net, total);
555
556 mutex_unlock(&hash_resize_mutex);
557 }
558
559 static void xfrm_hash_rebuild(struct work_struct *work)
560 {
561 struct net *net = container_of(work, struct net,
562 xfrm.policy_hthresh.work);
563 unsigned int hmask;
564 struct xfrm_policy *pol;
565 struct xfrm_policy *policy;
566 struct hlist_head *chain;
567 struct hlist_head *odst;
568 struct hlist_node *newpos;
569 int i;
570 int dir;
571 unsigned seq;
572 u8 lbits4, rbits4, lbits6, rbits6;
573
574 mutex_lock(&hash_resize_mutex);
575
576 /* read selector prefixlen thresholds */
577 do {
578 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
579
580 lbits4 = net->xfrm.policy_hthresh.lbits4;
581 rbits4 = net->xfrm.policy_hthresh.rbits4;
582 lbits6 = net->xfrm.policy_hthresh.lbits6;
583 rbits6 = net->xfrm.policy_hthresh.rbits6;
584 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
585
586 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
587
588 /* reset the bydst and inexact table in all directions */
589 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
590 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
591 hmask = net->xfrm.policy_bydst[dir].hmask;
592 odst = net->xfrm.policy_bydst[dir].table;
593 for (i = hmask; i >= 0; i--)
594 INIT_HLIST_HEAD(odst + i);
595 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
596 /* dir out => dst = remote, src = local */
597 net->xfrm.policy_bydst[dir].dbits4 = rbits4;
598 net->xfrm.policy_bydst[dir].sbits4 = lbits4;
599 net->xfrm.policy_bydst[dir].dbits6 = rbits6;
600 net->xfrm.policy_bydst[dir].sbits6 = lbits6;
601 } else {
602 /* dir in/fwd => dst = local, src = remote */
603 net->xfrm.policy_bydst[dir].dbits4 = lbits4;
604 net->xfrm.policy_bydst[dir].sbits4 = rbits4;
605 net->xfrm.policy_bydst[dir].dbits6 = lbits6;
606 net->xfrm.policy_bydst[dir].sbits6 = rbits6;
607 }
608 }
609
610 /* re-insert all policies by order of creation */
611 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
612 if (xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
613 /* skip socket policies */
614 continue;
615 }
616 newpos = NULL;
617 chain = policy_hash_bysel(net, &policy->selector,
618 policy->family,
619 xfrm_policy_id2dir(policy->index));
620 hlist_for_each_entry(pol, chain, bydst) {
621 if (policy->priority >= pol->priority)
622 newpos = &pol->bydst;
623 else
624 break;
625 }
626 if (newpos)
627 hlist_add_behind(&policy->bydst, newpos);
628 else
629 hlist_add_head(&policy->bydst, chain);
630 }
631
632 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
633
634 mutex_unlock(&hash_resize_mutex);
635 }
636
637 void xfrm_policy_hash_rebuild(struct net *net)
638 {
639 schedule_work(&net->xfrm.policy_hthresh.work);
640 }
641 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
642
643 /* Generate new index... KAME seems to generate them ordered by cost
644 * of an absolute inpredictability of ordering of rules. This will not pass. */
645 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
646 {
647 static u32 idx_generator;
648
649 for (;;) {
650 struct hlist_head *list;
651 struct xfrm_policy *p;
652 u32 idx;
653 int found;
654
655 if (!index) {
656 idx = (idx_generator | dir);
657 idx_generator += 8;
658 } else {
659 idx = index;
660 index = 0;
661 }
662
663 if (idx == 0)
664 idx = 8;
665 list = net->xfrm.policy_byidx + idx_hash(net, idx);
666 found = 0;
667 hlist_for_each_entry(p, list, byidx) {
668 if (p->index == idx) {
669 found = 1;
670 break;
671 }
672 }
673 if (!found)
674 return idx;
675 }
676 }
677
678 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
679 {
680 u32 *p1 = (u32 *) s1;
681 u32 *p2 = (u32 *) s2;
682 int len = sizeof(struct xfrm_selector) / sizeof(u32);
683 int i;
684
685 for (i = 0; i < len; i++) {
686 if (p1[i] != p2[i])
687 return 1;
688 }
689
690 return 0;
691 }
692
693 static void xfrm_policy_requeue(struct xfrm_policy *old,
694 struct xfrm_policy *new)
695 {
696 struct xfrm_policy_queue *pq = &old->polq;
697 struct sk_buff_head list;
698
699 if (skb_queue_empty(&pq->hold_queue))
700 return;
701
702 __skb_queue_head_init(&list);
703
704 spin_lock_bh(&pq->hold_queue.lock);
705 skb_queue_splice_init(&pq->hold_queue, &list);
706 if (del_timer(&pq->hold_timer))
707 xfrm_pol_put(old);
708 spin_unlock_bh(&pq->hold_queue.lock);
709
710 pq = &new->polq;
711
712 spin_lock_bh(&pq->hold_queue.lock);
713 skb_queue_splice(&list, &pq->hold_queue);
714 pq->timeout = XFRM_QUEUE_TMO_MIN;
715 if (!mod_timer(&pq->hold_timer, jiffies))
716 xfrm_pol_hold(new);
717 spin_unlock_bh(&pq->hold_queue.lock);
718 }
719
720 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
721 struct xfrm_policy *pol)
722 {
723 u32 mark = policy->mark.v & policy->mark.m;
724
725 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
726 return true;
727
728 if ((mark & pol->mark.m) == pol->mark.v &&
729 policy->priority == pol->priority)
730 return true;
731
732 return false;
733 }
734
735 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
736 {
737 struct net *net = xp_net(policy);
738 struct xfrm_policy *pol;
739 struct xfrm_policy *delpol;
740 struct hlist_head *chain;
741 struct hlist_node *newpos;
742
743 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
744 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
745 delpol = NULL;
746 newpos = NULL;
747 hlist_for_each_entry(pol, chain, bydst) {
748 if (pol->type == policy->type &&
749 !selector_cmp(&pol->selector, &policy->selector) &&
750 xfrm_policy_mark_match(policy, pol) &&
751 xfrm_sec_ctx_match(pol->security, policy->security) &&
752 !WARN_ON(delpol)) {
753 if (excl) {
754 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
755 return -EEXIST;
756 }
757 delpol = pol;
758 if (policy->priority > pol->priority)
759 continue;
760 } else if (policy->priority >= pol->priority) {
761 newpos = &pol->bydst;
762 continue;
763 }
764 if (delpol)
765 break;
766 }
767 if (newpos)
768 hlist_add_behind(&policy->bydst, newpos);
769 else
770 hlist_add_head(&policy->bydst, chain);
771 __xfrm_policy_link(policy, dir);
772
773 /* After previous checking, family can either be AF_INET or AF_INET6 */
774 if (policy->family == AF_INET)
775 rt_genid_bump_ipv4(net);
776 else
777 rt_genid_bump_ipv6(net);
778
779 if (delpol) {
780 xfrm_policy_requeue(delpol, policy);
781 __xfrm_policy_unlink(delpol, dir);
782 }
783 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
784 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
785 policy->curlft.add_time = get_seconds();
786 policy->curlft.use_time = 0;
787 if (!mod_timer(&policy->timer, jiffies + HZ))
788 xfrm_pol_hold(policy);
789 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
790
791 if (delpol)
792 xfrm_policy_kill(delpol);
793 else if (xfrm_bydst_should_resize(net, dir, NULL))
794 schedule_work(&net->xfrm.policy_hash_work);
795
796 return 0;
797 }
798 EXPORT_SYMBOL(xfrm_policy_insert);
799
800 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
801 int dir, struct xfrm_selector *sel,
802 struct xfrm_sec_ctx *ctx, int delete,
803 int *err)
804 {
805 struct xfrm_policy *pol, *ret;
806 struct hlist_head *chain;
807
808 *err = 0;
809 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
810 chain = policy_hash_bysel(net, sel, sel->family, dir);
811 ret = NULL;
812 hlist_for_each_entry(pol, chain, bydst) {
813 if (pol->type == type &&
814 (mark & pol->mark.m) == pol->mark.v &&
815 !selector_cmp(sel, &pol->selector) &&
816 xfrm_sec_ctx_match(ctx, pol->security)) {
817 xfrm_pol_hold(pol);
818 if (delete) {
819 *err = security_xfrm_policy_delete(
820 pol->security);
821 if (*err) {
822 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
823 return pol;
824 }
825 __xfrm_policy_unlink(pol, dir);
826 }
827 ret = pol;
828 break;
829 }
830 }
831 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
832
833 if (ret && delete)
834 xfrm_policy_kill(ret);
835 return ret;
836 }
837 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
838
839 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
840 int dir, u32 id, int delete, int *err)
841 {
842 struct xfrm_policy *pol, *ret;
843 struct hlist_head *chain;
844
845 *err = -ENOENT;
846 if (xfrm_policy_id2dir(id) != dir)
847 return NULL;
848
849 *err = 0;
850 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
851 chain = net->xfrm.policy_byidx + idx_hash(net, id);
852 ret = NULL;
853 hlist_for_each_entry(pol, chain, byidx) {
854 if (pol->type == type && pol->index == id &&
855 (mark & pol->mark.m) == pol->mark.v) {
856 xfrm_pol_hold(pol);
857 if (delete) {
858 *err = security_xfrm_policy_delete(
859 pol->security);
860 if (*err) {
861 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
862 return pol;
863 }
864 __xfrm_policy_unlink(pol, dir);
865 }
866 ret = pol;
867 break;
868 }
869 }
870 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
871
872 if (ret && delete)
873 xfrm_policy_kill(ret);
874 return ret;
875 }
876 EXPORT_SYMBOL(xfrm_policy_byid);
877
878 #ifdef CONFIG_SECURITY_NETWORK_XFRM
879 static inline int
880 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
881 {
882 int dir, err = 0;
883
884 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
885 struct xfrm_policy *pol;
886 int i;
887
888 hlist_for_each_entry(pol,
889 &net->xfrm.policy_inexact[dir], bydst) {
890 if (pol->type != type)
891 continue;
892 err = security_xfrm_policy_delete(pol->security);
893 if (err) {
894 xfrm_audit_policy_delete(pol, 0, task_valid);
895 return err;
896 }
897 }
898 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
899 hlist_for_each_entry(pol,
900 net->xfrm.policy_bydst[dir].table + i,
901 bydst) {
902 if (pol->type != type)
903 continue;
904 err = security_xfrm_policy_delete(
905 pol->security);
906 if (err) {
907 xfrm_audit_policy_delete(pol, 0,
908 task_valid);
909 return err;
910 }
911 }
912 }
913 }
914 return err;
915 }
916 #else
917 static inline int
918 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
919 {
920 return 0;
921 }
922 #endif
923
924 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
925 {
926 int dir, err = 0, cnt = 0;
927
928 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
929
930 err = xfrm_policy_flush_secctx_check(net, type, task_valid);
931 if (err)
932 goto out;
933
934 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
935 struct xfrm_policy *pol;
936 int i;
937
938 again1:
939 hlist_for_each_entry(pol,
940 &net->xfrm.policy_inexact[dir], bydst) {
941 if (pol->type != type)
942 continue;
943 __xfrm_policy_unlink(pol, dir);
944 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
945 cnt++;
946
947 xfrm_audit_policy_delete(pol, 1, task_valid);
948
949 xfrm_policy_kill(pol);
950
951 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
952 goto again1;
953 }
954
955 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
956 again2:
957 hlist_for_each_entry(pol,
958 net->xfrm.policy_bydst[dir].table + i,
959 bydst) {
960 if (pol->type != type)
961 continue;
962 __xfrm_policy_unlink(pol, dir);
963 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
964 cnt++;
965
966 xfrm_audit_policy_delete(pol, 1, task_valid);
967 xfrm_policy_kill(pol);
968
969 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
970 goto again2;
971 }
972 }
973
974 }
975 if (!cnt)
976 err = -ESRCH;
977 else
978 xfrm_policy_cache_flush();
979 out:
980 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
981 return err;
982 }
983 EXPORT_SYMBOL(xfrm_policy_flush);
984
985 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
986 int (*func)(struct xfrm_policy *, int, int, void*),
987 void *data)
988 {
989 struct xfrm_policy *pol;
990 struct xfrm_policy_walk_entry *x;
991 int error = 0;
992
993 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
994 walk->type != XFRM_POLICY_TYPE_ANY)
995 return -EINVAL;
996
997 if (list_empty(&walk->walk.all) && walk->seq != 0)
998 return 0;
999
1000 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1001 if (list_empty(&walk->walk.all))
1002 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1003 else
1004 x = list_first_entry(&walk->walk.all,
1005 struct xfrm_policy_walk_entry, all);
1006
1007 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1008 if (x->dead)
1009 continue;
1010 pol = container_of(x, struct xfrm_policy, walk);
1011 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1012 walk->type != pol->type)
1013 continue;
1014 error = func(pol, xfrm_policy_id2dir(pol->index),
1015 walk->seq, data);
1016 if (error) {
1017 list_move_tail(&walk->walk.all, &x->all);
1018 goto out;
1019 }
1020 walk->seq++;
1021 }
1022 if (walk->seq == 0) {
1023 error = -ENOENT;
1024 goto out;
1025 }
1026 list_del_init(&walk->walk.all);
1027 out:
1028 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1029 return error;
1030 }
1031 EXPORT_SYMBOL(xfrm_policy_walk);
1032
1033 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1034 {
1035 INIT_LIST_HEAD(&walk->walk.all);
1036 walk->walk.dead = 1;
1037 walk->type = type;
1038 walk->seq = 0;
1039 }
1040 EXPORT_SYMBOL(xfrm_policy_walk_init);
1041
1042 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1043 {
1044 if (list_empty(&walk->walk.all))
1045 return;
1046
1047 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1048 list_del(&walk->walk.all);
1049 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1050 }
1051 EXPORT_SYMBOL(xfrm_policy_walk_done);
1052
1053 /*
1054 * Find policy to apply to this flow.
1055 *
1056 * Returns 0 if policy found, else an -errno.
1057 */
1058 static int xfrm_policy_match(const struct xfrm_policy *pol,
1059 const struct flowi *fl,
1060 u8 type, u16 family, int dir)
1061 {
1062 const struct xfrm_selector *sel = &pol->selector;
1063 int ret = -ESRCH;
1064 bool match;
1065
1066 if (pol->family != family ||
1067 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1068 pol->type != type)
1069 return ret;
1070
1071 match = xfrm_selector_match(sel, fl, family);
1072 if (match)
1073 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1074 dir);
1075
1076 return ret;
1077 }
1078
1079 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1080 const struct flowi *fl,
1081 u16 family, u8 dir)
1082 {
1083 int err;
1084 struct xfrm_policy *pol, *ret;
1085 const xfrm_address_t *daddr, *saddr;
1086 struct hlist_head *chain;
1087 unsigned int sequence;
1088 u32 priority;
1089
1090 daddr = xfrm_flowi_daddr(fl, family);
1091 saddr = xfrm_flowi_saddr(fl, family);
1092 if (unlikely(!daddr || !saddr))
1093 return NULL;
1094
1095 rcu_read_lock();
1096 retry:
1097 do {
1098 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1099 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1100 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1101
1102 priority = ~0U;
1103 ret = NULL;
1104 hlist_for_each_entry_rcu(pol, chain, bydst) {
1105 err = xfrm_policy_match(pol, fl, type, family, dir);
1106 if (err) {
1107 if (err == -ESRCH)
1108 continue;
1109 else {
1110 ret = ERR_PTR(err);
1111 goto fail;
1112 }
1113 } else {
1114 ret = pol;
1115 priority = ret->priority;
1116 break;
1117 }
1118 }
1119 chain = &net->xfrm.policy_inexact[dir];
1120 hlist_for_each_entry_rcu(pol, chain, bydst) {
1121 if ((pol->priority >= priority) && ret)
1122 break;
1123
1124 err = xfrm_policy_match(pol, fl, type, family, dir);
1125 if (err) {
1126 if (err == -ESRCH)
1127 continue;
1128 else {
1129 ret = ERR_PTR(err);
1130 goto fail;
1131 }
1132 } else {
1133 ret = pol;
1134 break;
1135 }
1136 }
1137
1138 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1139 goto retry;
1140
1141 if (ret && !xfrm_pol_hold_rcu(ret))
1142 goto retry;
1143 fail:
1144 rcu_read_unlock();
1145
1146 return ret;
1147 }
1148
1149 static struct xfrm_policy *
1150 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1151 {
1152 #ifdef CONFIG_XFRM_SUB_POLICY
1153 struct xfrm_policy *pol;
1154
1155 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1156 if (pol != NULL)
1157 return pol;
1158 #endif
1159 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1160 }
1161
1162 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1163 const struct flowi *fl, u16 family)
1164 {
1165 struct xfrm_policy *pol;
1166
1167 rcu_read_lock();
1168 again:
1169 pol = rcu_dereference(sk->sk_policy[dir]);
1170 if (pol != NULL) {
1171 bool match = xfrm_selector_match(&pol->selector, fl, family);
1172 int err = 0;
1173
1174 if (match) {
1175 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1176 pol = NULL;
1177 goto out;
1178 }
1179 err = security_xfrm_policy_lookup(pol->security,
1180 fl->flowi_secid,
1181 dir);
1182 if (!err) {
1183 if (!xfrm_pol_hold_rcu(pol))
1184 goto again;
1185 } else if (err == -ESRCH) {
1186 pol = NULL;
1187 } else {
1188 pol = ERR_PTR(err);
1189 }
1190 } else
1191 pol = NULL;
1192 }
1193 out:
1194 rcu_read_unlock();
1195 return pol;
1196 }
1197
1198 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1199 {
1200 struct net *net = xp_net(pol);
1201
1202 list_add(&pol->walk.all, &net->xfrm.policy_all);
1203 net->xfrm.policy_count[dir]++;
1204 xfrm_pol_hold(pol);
1205 }
1206
1207 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1208 int dir)
1209 {
1210 struct net *net = xp_net(pol);
1211
1212 if (list_empty(&pol->walk.all))
1213 return NULL;
1214
1215 /* Socket policies are not hashed. */
1216 if (!hlist_unhashed(&pol->bydst)) {
1217 hlist_del_rcu(&pol->bydst);
1218 hlist_del(&pol->byidx);
1219 }
1220
1221 list_del_init(&pol->walk.all);
1222 net->xfrm.policy_count[dir]--;
1223
1224 return pol;
1225 }
1226
1227 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1228 {
1229 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1230 }
1231
1232 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1233 {
1234 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1235 }
1236
1237 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1238 {
1239 struct net *net = xp_net(pol);
1240
1241 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1242 pol = __xfrm_policy_unlink(pol, dir);
1243 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1244 if (pol) {
1245 xfrm_policy_kill(pol);
1246 return 0;
1247 }
1248 return -ENOENT;
1249 }
1250 EXPORT_SYMBOL(xfrm_policy_delete);
1251
1252 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1253 {
1254 struct net *net = xp_net(pol);
1255 struct xfrm_policy *old_pol;
1256
1257 #ifdef CONFIG_XFRM_SUB_POLICY
1258 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1259 return -EINVAL;
1260 #endif
1261
1262 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1263 old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1264 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1265 if (pol) {
1266 pol->curlft.add_time = get_seconds();
1267 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1268 xfrm_sk_policy_link(pol, dir);
1269 }
1270 rcu_assign_pointer(sk->sk_policy[dir], pol);
1271 if (old_pol) {
1272 if (pol)
1273 xfrm_policy_requeue(old_pol, pol);
1274
1275 /* Unlinking succeeds always. This is the only function
1276 * allowed to delete or replace socket policy.
1277 */
1278 xfrm_sk_policy_unlink(old_pol, dir);
1279 }
1280 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1281
1282 if (old_pol) {
1283 xfrm_policy_kill(old_pol);
1284 }
1285 return 0;
1286 }
1287
1288 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1289 {
1290 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1291 struct net *net = xp_net(old);
1292
1293 if (newp) {
1294 newp->selector = old->selector;
1295 if (security_xfrm_policy_clone(old->security,
1296 &newp->security)) {
1297 kfree(newp);
1298 return NULL; /* ENOMEM */
1299 }
1300 newp->lft = old->lft;
1301 newp->curlft = old->curlft;
1302 newp->mark = old->mark;
1303 newp->action = old->action;
1304 newp->flags = old->flags;
1305 newp->xfrm_nr = old->xfrm_nr;
1306 newp->index = old->index;
1307 newp->type = old->type;
1308 newp->family = old->family;
1309 memcpy(newp->xfrm_vec, old->xfrm_vec,
1310 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1311 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1312 xfrm_sk_policy_link(newp, dir);
1313 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1314 xfrm_pol_put(newp);
1315 }
1316 return newp;
1317 }
1318
1319 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1320 {
1321 const struct xfrm_policy *p;
1322 struct xfrm_policy *np;
1323 int i, ret = 0;
1324
1325 rcu_read_lock();
1326 for (i = 0; i < 2; i++) {
1327 p = rcu_dereference(osk->sk_policy[i]);
1328 if (p) {
1329 np = clone_policy(p, i);
1330 if (unlikely(!np)) {
1331 ret = -ENOMEM;
1332 break;
1333 }
1334 rcu_assign_pointer(sk->sk_policy[i], np);
1335 }
1336 }
1337 rcu_read_unlock();
1338 return ret;
1339 }
1340
1341 static int
1342 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1343 xfrm_address_t *remote, unsigned short family, u32 mark)
1344 {
1345 int err;
1346 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1347
1348 if (unlikely(afinfo == NULL))
1349 return -EINVAL;
1350 err = afinfo->get_saddr(net, oif, local, remote, mark);
1351 rcu_read_unlock();
1352 return err;
1353 }
1354
1355 /* Resolve list of templates for the flow, given policy. */
1356
1357 static int
1358 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1359 struct xfrm_state **xfrm, unsigned short family)
1360 {
1361 struct net *net = xp_net(policy);
1362 int nx;
1363 int i, error;
1364 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1365 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1366 xfrm_address_t tmp;
1367
1368 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1369 struct xfrm_state *x;
1370 xfrm_address_t *remote = daddr;
1371 xfrm_address_t *local = saddr;
1372 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1373
1374 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1375 tmpl->mode == XFRM_MODE_BEET) {
1376 remote = &tmpl->id.daddr;
1377 local = &tmpl->saddr;
1378 if (xfrm_addr_any(local, tmpl->encap_family)) {
1379 error = xfrm_get_saddr(net, fl->flowi_oif,
1380 &tmp, remote,
1381 tmpl->encap_family, 0);
1382 if (error)
1383 goto fail;
1384 local = &tmp;
1385 }
1386 }
1387
1388 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1389
1390 if (x && x->km.state == XFRM_STATE_VALID) {
1391 xfrm[nx++] = x;
1392 daddr = remote;
1393 saddr = local;
1394 continue;
1395 }
1396 if (x) {
1397 error = (x->km.state == XFRM_STATE_ERROR ?
1398 -EINVAL : -EAGAIN);
1399 xfrm_state_put(x);
1400 } else if (error == -ESRCH) {
1401 error = -EAGAIN;
1402 }
1403
1404 if (!tmpl->optional)
1405 goto fail;
1406 }
1407 return nx;
1408
1409 fail:
1410 for (nx--; nx >= 0; nx--)
1411 xfrm_state_put(xfrm[nx]);
1412 return error;
1413 }
1414
1415 static int
1416 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1417 struct xfrm_state **xfrm, unsigned short family)
1418 {
1419 struct xfrm_state *tp[XFRM_MAX_DEPTH];
1420 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1421 int cnx = 0;
1422 int error;
1423 int ret;
1424 int i;
1425
1426 for (i = 0; i < npols; i++) {
1427 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1428 error = -ENOBUFS;
1429 goto fail;
1430 }
1431
1432 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1433 if (ret < 0) {
1434 error = ret;
1435 goto fail;
1436 } else
1437 cnx += ret;
1438 }
1439
1440 /* found states are sorted for outbound processing */
1441 if (npols > 1)
1442 xfrm_state_sort(xfrm, tpp, cnx, family);
1443
1444 return cnx;
1445
1446 fail:
1447 for (cnx--; cnx >= 0; cnx--)
1448 xfrm_state_put(tpp[cnx]);
1449 return error;
1450
1451 }
1452
1453 static int xfrm_get_tos(const struct flowi *fl, int family)
1454 {
1455 const struct xfrm_policy_afinfo *afinfo;
1456 int tos = 0;
1457
1458 afinfo = xfrm_policy_get_afinfo(family);
1459 tos = afinfo ? afinfo->get_tos(fl) : 0;
1460
1461 rcu_read_unlock();
1462
1463 return tos;
1464 }
1465
1466 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1467 {
1468 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1469 struct dst_ops *dst_ops;
1470 struct xfrm_dst *xdst;
1471
1472 if (!afinfo)
1473 return ERR_PTR(-EINVAL);
1474
1475 switch (family) {
1476 case AF_INET:
1477 dst_ops = &net->xfrm.xfrm4_dst_ops;
1478 break;
1479 #if IS_ENABLED(CONFIG_IPV6)
1480 case AF_INET6:
1481 dst_ops = &net->xfrm.xfrm6_dst_ops;
1482 break;
1483 #endif
1484 default:
1485 BUG();
1486 }
1487 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
1488
1489 if (likely(xdst)) {
1490 struct dst_entry *dst = &xdst->u.dst;
1491
1492 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1493 } else
1494 xdst = ERR_PTR(-ENOBUFS);
1495
1496 rcu_read_unlock();
1497
1498 return xdst;
1499 }
1500
1501 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1502 int nfheader_len)
1503 {
1504 const struct xfrm_policy_afinfo *afinfo =
1505 xfrm_policy_get_afinfo(dst->ops->family);
1506 int err;
1507
1508 if (!afinfo)
1509 return -EINVAL;
1510
1511 err = afinfo->init_path(path, dst, nfheader_len);
1512
1513 rcu_read_unlock();
1514
1515 return err;
1516 }
1517
1518 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1519 const struct flowi *fl)
1520 {
1521 const struct xfrm_policy_afinfo *afinfo =
1522 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1523 int err;
1524
1525 if (!afinfo)
1526 return -EINVAL;
1527
1528 err = afinfo->fill_dst(xdst, dev, fl);
1529
1530 rcu_read_unlock();
1531
1532 return err;
1533 }
1534
1535
1536 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1537 * all the metrics... Shortly, bundle a bundle.
1538 */
1539
1540 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1541 struct xfrm_state **xfrm, int nx,
1542 const struct flowi *fl,
1543 struct dst_entry *dst)
1544 {
1545 struct net *net = xp_net(policy);
1546 unsigned long now = jiffies;
1547 struct net_device *dev;
1548 struct xfrm_mode *inner_mode;
1549 struct dst_entry *dst_prev = NULL;
1550 struct dst_entry *dst0 = NULL;
1551 int i = 0;
1552 int err;
1553 int header_len = 0;
1554 int nfheader_len = 0;
1555 int trailer_len = 0;
1556 int tos;
1557 int family = policy->selector.family;
1558 xfrm_address_t saddr, daddr;
1559
1560 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1561
1562 tos = xfrm_get_tos(fl, family);
1563
1564 dst_hold(dst);
1565
1566 for (; i < nx; i++) {
1567 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1568 struct dst_entry *dst1 = &xdst->u.dst;
1569
1570 err = PTR_ERR(xdst);
1571 if (IS_ERR(xdst)) {
1572 dst_release(dst);
1573 goto put_states;
1574 }
1575
1576 if (!dst_prev)
1577 dst0 = dst1;
1578 else
1579 /* Ref count is taken during xfrm_alloc_dst()
1580 * No need to do dst_clone() on dst1
1581 */
1582 dst_prev->child = dst1;
1583
1584 if (xfrm[i]->sel.family == AF_UNSPEC) {
1585 inner_mode = xfrm_ip2inner_mode(xfrm[i],
1586 xfrm_af2proto(family));
1587 if (!inner_mode) {
1588 err = -EAFNOSUPPORT;
1589 dst_release(dst);
1590 goto put_states;
1591 }
1592 } else
1593 inner_mode = xfrm[i]->inner_mode;
1594
1595 xdst->route = dst;
1596 dst_copy_metrics(dst1, dst);
1597
1598 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1599 family = xfrm[i]->props.family;
1600 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1601 &saddr, &daddr, family,
1602 xfrm[i]->props.output_mark);
1603 err = PTR_ERR(dst);
1604 if (IS_ERR(dst))
1605 goto put_states;
1606 } else
1607 dst_hold(dst);
1608
1609 dst1->xfrm = xfrm[i];
1610 xdst->xfrm_genid = xfrm[i]->genid;
1611
1612 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1613 dst1->flags |= DST_HOST;
1614 dst1->lastuse = now;
1615
1616 dst1->input = dst_discard;
1617 dst1->output = inner_mode->afinfo->output;
1618
1619 dst1->next = dst_prev;
1620 dst_prev = dst1;
1621
1622 header_len += xfrm[i]->props.header_len;
1623 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1624 nfheader_len += xfrm[i]->props.header_len;
1625 trailer_len += xfrm[i]->props.trailer_len;
1626 }
1627
1628 dst_prev->child = dst;
1629 dst0->path = dst;
1630
1631 err = -ENODEV;
1632 dev = dst->dev;
1633 if (!dev)
1634 goto free_dst;
1635
1636 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1637 xfrm_init_pmtu(dst_prev);
1638
1639 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1640 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1641
1642 err = xfrm_fill_dst(xdst, dev, fl);
1643 if (err)
1644 goto free_dst;
1645
1646 dst_prev->header_len = header_len;
1647 dst_prev->trailer_len = trailer_len;
1648 header_len -= xdst->u.dst.xfrm->props.header_len;
1649 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1650 }
1651
1652 out:
1653 return dst0;
1654
1655 put_states:
1656 for (; i < nx; i++)
1657 xfrm_state_put(xfrm[i]);
1658 free_dst:
1659 if (dst0)
1660 dst_release_immediate(dst0);
1661 dst0 = ERR_PTR(err);
1662 goto out;
1663 }
1664
1665 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1666 struct xfrm_policy **pols,
1667 int *num_pols, int *num_xfrms)
1668 {
1669 int i;
1670
1671 if (*num_pols == 0 || !pols[0]) {
1672 *num_pols = 0;
1673 *num_xfrms = 0;
1674 return 0;
1675 }
1676 if (IS_ERR(pols[0]))
1677 return PTR_ERR(pols[0]);
1678
1679 *num_xfrms = pols[0]->xfrm_nr;
1680
1681 #ifdef CONFIG_XFRM_SUB_POLICY
1682 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1683 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1684 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1685 XFRM_POLICY_TYPE_MAIN,
1686 fl, family,
1687 XFRM_POLICY_OUT);
1688 if (pols[1]) {
1689 if (IS_ERR(pols[1])) {
1690 xfrm_pols_put(pols, *num_pols);
1691 return PTR_ERR(pols[1]);
1692 }
1693 (*num_pols)++;
1694 (*num_xfrms) += pols[1]->xfrm_nr;
1695 }
1696 }
1697 #endif
1698 for (i = 0; i < *num_pols; i++) {
1699 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1700 *num_xfrms = -1;
1701 break;
1702 }
1703 }
1704
1705 return 0;
1706
1707 }
1708
1709 static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old)
1710 {
1711 this_cpu_write(xfrm_last_dst, xdst);
1712 if (old)
1713 dst_release(&old->u.dst);
1714 }
1715
1716 static void __xfrm_pcpu_work_fn(void)
1717 {
1718 struct xfrm_dst *old;
1719
1720 old = this_cpu_read(xfrm_last_dst);
1721 if (old && !xfrm_bundle_ok(old))
1722 xfrm_last_dst_update(NULL, old);
1723 }
1724
1725 static void xfrm_pcpu_work_fn(struct work_struct *work)
1726 {
1727 local_bh_disable();
1728 rcu_read_lock();
1729 __xfrm_pcpu_work_fn();
1730 rcu_read_unlock();
1731 local_bh_enable();
1732 }
1733
1734 void xfrm_policy_cache_flush(void)
1735 {
1736 struct xfrm_dst *old;
1737 bool found = 0;
1738 int cpu;
1739
1740 local_bh_disable();
1741 rcu_read_lock();
1742 for_each_possible_cpu(cpu) {
1743 old = per_cpu(xfrm_last_dst, cpu);
1744 if (old && !xfrm_bundle_ok(old)) {
1745 if (smp_processor_id() == cpu) {
1746 __xfrm_pcpu_work_fn();
1747 continue;
1748 }
1749 found = true;
1750 break;
1751 }
1752 }
1753
1754 rcu_read_unlock();
1755 local_bh_enable();
1756
1757 if (!found)
1758 return;
1759
1760 get_online_cpus();
1761
1762 for_each_possible_cpu(cpu) {
1763 bool bundle_release;
1764
1765 rcu_read_lock();
1766 old = per_cpu(xfrm_last_dst, cpu);
1767 bundle_release = old && !xfrm_bundle_ok(old);
1768 rcu_read_unlock();
1769
1770 if (!bundle_release)
1771 continue;
1772
1773 if (cpu_online(cpu)) {
1774 schedule_work_on(cpu, &xfrm_pcpu_work[cpu]);
1775 continue;
1776 }
1777
1778 rcu_read_lock();
1779 old = per_cpu(xfrm_last_dst, cpu);
1780 if (old && !xfrm_bundle_ok(old)) {
1781 per_cpu(xfrm_last_dst, cpu) = NULL;
1782 dst_release(&old->u.dst);
1783 }
1784 rcu_read_unlock();
1785 }
1786
1787 put_online_cpus();
1788 }
1789
1790 static bool xfrm_xdst_can_reuse(struct xfrm_dst *xdst,
1791 struct xfrm_state * const xfrm[],
1792 int num)
1793 {
1794 const struct dst_entry *dst = &xdst->u.dst;
1795 int i;
1796
1797 if (xdst->num_xfrms != num)
1798 return false;
1799
1800 for (i = 0; i < num; i++) {
1801 if (!dst || dst->xfrm != xfrm[i])
1802 return false;
1803 dst = dst->child;
1804 }
1805
1806 return xfrm_bundle_ok(xdst);
1807 }
1808
1809 static struct xfrm_dst *
1810 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1811 const struct flowi *fl, u16 family,
1812 struct dst_entry *dst_orig)
1813 {
1814 struct net *net = xp_net(pols[0]);
1815 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1816 struct xfrm_dst *xdst, *old;
1817 struct dst_entry *dst;
1818 int err;
1819
1820 /* Try to instantiate a bundle */
1821 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1822 if (err <= 0) {
1823 if (err != 0 && err != -EAGAIN)
1824 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1825 return ERR_PTR(err);
1826 }
1827
1828 xdst = this_cpu_read(xfrm_last_dst);
1829 if (xdst &&
1830 xdst->u.dst.dev == dst_orig->dev &&
1831 xdst->num_pols == num_pols &&
1832 memcmp(xdst->pols, pols,
1833 sizeof(struct xfrm_policy *) * num_pols) == 0 &&
1834 xfrm_xdst_can_reuse(xdst, xfrm, err)) {
1835 dst_hold(&xdst->u.dst);
1836 while (err > 0)
1837 xfrm_state_put(xfrm[--err]);
1838 return xdst;
1839 }
1840
1841 old = xdst;
1842
1843 dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1844 if (IS_ERR(dst)) {
1845 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1846 return ERR_CAST(dst);
1847 }
1848
1849 xdst = (struct xfrm_dst *)dst;
1850 xdst->num_xfrms = err;
1851 xdst->num_pols = num_pols;
1852 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1853 xdst->policy_genid = atomic_read(&pols[0]->genid);
1854
1855 atomic_set(&xdst->u.dst.__refcnt, 2);
1856 xfrm_last_dst_update(xdst, old);
1857
1858 return xdst;
1859 }
1860
1861 static void xfrm_policy_queue_process(struct timer_list *t)
1862 {
1863 struct sk_buff *skb;
1864 struct sock *sk;
1865 struct dst_entry *dst;
1866 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
1867 struct net *net = xp_net(pol);
1868 struct xfrm_policy_queue *pq = &pol->polq;
1869 struct flowi fl;
1870 struct sk_buff_head list;
1871
1872 spin_lock(&pq->hold_queue.lock);
1873 skb = skb_peek(&pq->hold_queue);
1874 if (!skb) {
1875 spin_unlock(&pq->hold_queue.lock);
1876 goto out;
1877 }
1878 dst = skb_dst(skb);
1879 sk = skb->sk;
1880 xfrm_decode_session(skb, &fl, dst->ops->family);
1881 spin_unlock(&pq->hold_queue.lock);
1882
1883 dst_hold(dst->path);
1884 dst = xfrm_lookup(net, dst->path, &fl, sk, 0);
1885 if (IS_ERR(dst))
1886 goto purge_queue;
1887
1888 if (dst->flags & DST_XFRM_QUEUE) {
1889 dst_release(dst);
1890
1891 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1892 goto purge_queue;
1893
1894 pq->timeout = pq->timeout << 1;
1895 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1896 xfrm_pol_hold(pol);
1897 goto out;
1898 }
1899
1900 dst_release(dst);
1901
1902 __skb_queue_head_init(&list);
1903
1904 spin_lock(&pq->hold_queue.lock);
1905 pq->timeout = 0;
1906 skb_queue_splice_init(&pq->hold_queue, &list);
1907 spin_unlock(&pq->hold_queue.lock);
1908
1909 while (!skb_queue_empty(&list)) {
1910 skb = __skb_dequeue(&list);
1911
1912 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1913 dst_hold(skb_dst(skb)->path);
1914 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0);
1915 if (IS_ERR(dst)) {
1916 kfree_skb(skb);
1917 continue;
1918 }
1919
1920 nf_reset(skb);
1921 skb_dst_drop(skb);
1922 skb_dst_set(skb, dst);
1923
1924 dst_output(net, skb->sk, skb);
1925 }
1926
1927 out:
1928 xfrm_pol_put(pol);
1929 return;
1930
1931 purge_queue:
1932 pq->timeout = 0;
1933 skb_queue_purge(&pq->hold_queue);
1934 xfrm_pol_put(pol);
1935 }
1936
1937 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1938 {
1939 unsigned long sched_next;
1940 struct dst_entry *dst = skb_dst(skb);
1941 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1942 struct xfrm_policy *pol = xdst->pols[0];
1943 struct xfrm_policy_queue *pq = &pol->polq;
1944
1945 if (unlikely(skb_fclone_busy(sk, skb))) {
1946 kfree_skb(skb);
1947 return 0;
1948 }
1949
1950 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1951 kfree_skb(skb);
1952 return -EAGAIN;
1953 }
1954
1955 skb_dst_force(skb);
1956
1957 spin_lock_bh(&pq->hold_queue.lock);
1958
1959 if (!pq->timeout)
1960 pq->timeout = XFRM_QUEUE_TMO_MIN;
1961
1962 sched_next = jiffies + pq->timeout;
1963
1964 if (del_timer(&pq->hold_timer)) {
1965 if (time_before(pq->hold_timer.expires, sched_next))
1966 sched_next = pq->hold_timer.expires;
1967 xfrm_pol_put(pol);
1968 }
1969
1970 __skb_queue_tail(&pq->hold_queue, skb);
1971 if (!mod_timer(&pq->hold_timer, sched_next))
1972 xfrm_pol_hold(pol);
1973
1974 spin_unlock_bh(&pq->hold_queue.lock);
1975
1976 return 0;
1977 }
1978
1979 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1980 struct xfrm_flo *xflo,
1981 const struct flowi *fl,
1982 int num_xfrms,
1983 u16 family)
1984 {
1985 int err;
1986 struct net_device *dev;
1987 struct dst_entry *dst;
1988 struct dst_entry *dst1;
1989 struct xfrm_dst *xdst;
1990
1991 xdst = xfrm_alloc_dst(net, family);
1992 if (IS_ERR(xdst))
1993 return xdst;
1994
1995 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
1996 net->xfrm.sysctl_larval_drop ||
1997 num_xfrms <= 0)
1998 return xdst;
1999
2000 dst = xflo->dst_orig;
2001 dst1 = &xdst->u.dst;
2002 dst_hold(dst);
2003 xdst->route = dst;
2004
2005 dst_copy_metrics(dst1, dst);
2006
2007 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2008 dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2009 dst1->lastuse = jiffies;
2010
2011 dst1->input = dst_discard;
2012 dst1->output = xdst_queue_output;
2013
2014 dst_hold(dst);
2015 dst1->child = dst;
2016 dst1->path = dst;
2017
2018 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2019
2020 err = -ENODEV;
2021 dev = dst->dev;
2022 if (!dev)
2023 goto free_dst;
2024
2025 err = xfrm_fill_dst(xdst, dev, fl);
2026 if (err)
2027 goto free_dst;
2028
2029 out:
2030 return xdst;
2031
2032 free_dst:
2033 dst_release(dst1);
2034 xdst = ERR_PTR(err);
2035 goto out;
2036 }
2037
2038 static struct xfrm_dst *
2039 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo)
2040 {
2041 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2042 int num_pols = 0, num_xfrms = 0, err;
2043 struct xfrm_dst *xdst;
2044
2045 /* Resolve policies to use if we couldn't get them from
2046 * previous cache entry */
2047 num_pols = 1;
2048 pols[0] = xfrm_policy_lookup(net, fl, family, dir);
2049 err = xfrm_expand_policies(fl, family, pols,
2050 &num_pols, &num_xfrms);
2051 if (err < 0)
2052 goto inc_error;
2053 if (num_pols == 0)
2054 return NULL;
2055 if (num_xfrms <= 0)
2056 goto make_dummy_bundle;
2057
2058 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2059 xflo->dst_orig);
2060 if (IS_ERR(xdst)) {
2061 err = PTR_ERR(xdst);
2062 if (err != -EAGAIN)
2063 goto error;
2064 goto make_dummy_bundle;
2065 } else if (xdst == NULL) {
2066 num_xfrms = 0;
2067 goto make_dummy_bundle;
2068 }
2069
2070 return xdst;
2071
2072 make_dummy_bundle:
2073 /* We found policies, but there's no bundles to instantiate:
2074 * either because the policy blocks, has no transformations or
2075 * we could not build template (no xfrm_states).*/
2076 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2077 if (IS_ERR(xdst)) {
2078 xfrm_pols_put(pols, num_pols);
2079 return ERR_CAST(xdst);
2080 }
2081 xdst->num_pols = num_pols;
2082 xdst->num_xfrms = num_xfrms;
2083 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2084
2085 return xdst;
2086
2087 inc_error:
2088 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2089 error:
2090 xfrm_pols_put(pols, num_pols);
2091 return ERR_PTR(err);
2092 }
2093
2094 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2095 struct dst_entry *dst_orig)
2096 {
2097 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2098 struct dst_entry *ret;
2099
2100 if (!afinfo) {
2101 dst_release(dst_orig);
2102 return ERR_PTR(-EINVAL);
2103 } else {
2104 ret = afinfo->blackhole_route(net, dst_orig);
2105 }
2106 rcu_read_unlock();
2107
2108 return ret;
2109 }
2110
2111 /* Main function: finds/creates a bundle for given flow.
2112 *
2113 * At the moment we eat a raw IP route. Mostly to speed up lookups
2114 * on interfaces with disabled IPsec.
2115 */
2116 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2117 const struct flowi *fl,
2118 const struct sock *sk, int flags)
2119 {
2120 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2121 struct xfrm_dst *xdst;
2122 struct dst_entry *dst, *route;
2123 u16 family = dst_orig->ops->family;
2124 u8 dir = XFRM_POLICY_OUT;
2125 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2126
2127 dst = NULL;
2128 xdst = NULL;
2129 route = NULL;
2130
2131 sk = sk_const_to_full_sk(sk);
2132 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2133 num_pols = 1;
2134 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family);
2135 err = xfrm_expand_policies(fl, family, pols,
2136 &num_pols, &num_xfrms);
2137 if (err < 0)
2138 goto dropdst;
2139
2140 if (num_pols) {
2141 if (num_xfrms <= 0) {
2142 drop_pols = num_pols;
2143 goto no_transform;
2144 }
2145
2146 xdst = xfrm_resolve_and_create_bundle(
2147 pols, num_pols, fl,
2148 family, dst_orig);
2149 if (IS_ERR(xdst)) {
2150 xfrm_pols_put(pols, num_pols);
2151 err = PTR_ERR(xdst);
2152 goto dropdst;
2153 } else if (xdst == NULL) {
2154 num_xfrms = 0;
2155 drop_pols = num_pols;
2156 goto no_transform;
2157 }
2158
2159 route = xdst->route;
2160 }
2161 }
2162
2163 if (xdst == NULL) {
2164 struct xfrm_flo xflo;
2165
2166 xflo.dst_orig = dst_orig;
2167 xflo.flags = flags;
2168
2169 /* To accelerate a bit... */
2170 if ((dst_orig->flags & DST_NOXFRM) ||
2171 !net->xfrm.policy_count[XFRM_POLICY_OUT])
2172 goto nopol;
2173
2174 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo);
2175 if (xdst == NULL)
2176 goto nopol;
2177 if (IS_ERR(xdst)) {
2178 err = PTR_ERR(xdst);
2179 goto dropdst;
2180 }
2181
2182 num_pols = xdst->num_pols;
2183 num_xfrms = xdst->num_xfrms;
2184 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2185 route = xdst->route;
2186 }
2187
2188 dst = &xdst->u.dst;
2189 if (route == NULL && num_xfrms > 0) {
2190 /* The only case when xfrm_bundle_lookup() returns a
2191 * bundle with null route, is when the template could
2192 * not be resolved. It means policies are there, but
2193 * bundle could not be created, since we don't yet
2194 * have the xfrm_state's. We need to wait for KM to
2195 * negotiate new SA's or bail out with error.*/
2196 if (net->xfrm.sysctl_larval_drop) {
2197 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2198 err = -EREMOTE;
2199 goto error;
2200 }
2201
2202 err = -EAGAIN;
2203
2204 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2205 goto error;
2206 }
2207
2208 no_transform:
2209 if (num_pols == 0)
2210 goto nopol;
2211
2212 if ((flags & XFRM_LOOKUP_ICMP) &&
2213 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2214 err = -ENOENT;
2215 goto error;
2216 }
2217
2218 for (i = 0; i < num_pols; i++)
2219 pols[i]->curlft.use_time = get_seconds();
2220
2221 if (num_xfrms < 0) {
2222 /* Prohibit the flow */
2223 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2224 err = -EPERM;
2225 goto error;
2226 } else if (num_xfrms > 0) {
2227 /* Flow transformed */
2228 dst_release(dst_orig);
2229 } else {
2230 /* Flow passes untransformed */
2231 dst_release(dst);
2232 dst = dst_orig;
2233 }
2234 ok:
2235 xfrm_pols_put(pols, drop_pols);
2236 if (dst && dst->xfrm &&
2237 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2238 dst->flags |= DST_XFRM_TUNNEL;
2239 return dst;
2240
2241 nopol:
2242 if (!(flags & XFRM_LOOKUP_ICMP)) {
2243 dst = dst_orig;
2244 goto ok;
2245 }
2246 err = -ENOENT;
2247 error:
2248 dst_release(dst);
2249 dropdst:
2250 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2251 dst_release(dst_orig);
2252 xfrm_pols_put(pols, drop_pols);
2253 return ERR_PTR(err);
2254 }
2255 EXPORT_SYMBOL(xfrm_lookup);
2256
2257 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2258 * Otherwise we may send out blackholed packets.
2259 */
2260 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2261 const struct flowi *fl,
2262 const struct sock *sk, int flags)
2263 {
2264 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2265 flags | XFRM_LOOKUP_QUEUE |
2266 XFRM_LOOKUP_KEEP_DST_REF);
2267
2268 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2269 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2270
2271 return dst;
2272 }
2273 EXPORT_SYMBOL(xfrm_lookup_route);
2274
2275 static inline int
2276 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2277 {
2278 struct xfrm_state *x;
2279
2280 if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2281 return 0;
2282 x = skb->sp->xvec[idx];
2283 if (!x->type->reject)
2284 return 0;
2285 return x->type->reject(x, skb, fl);
2286 }
2287
2288 /* When skb is transformed back to its "native" form, we have to
2289 * check policy restrictions. At the moment we make this in maximally
2290 * stupid way. Shame on me. :-) Of course, connected sockets must
2291 * have policy cached at them.
2292 */
2293
2294 static inline int
2295 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2296 unsigned short family)
2297 {
2298 if (xfrm_state_kern(x))
2299 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2300 return x->id.proto == tmpl->id.proto &&
2301 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2302 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2303 x->props.mode == tmpl->mode &&
2304 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2305 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2306 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2307 xfrm_state_addr_cmp(tmpl, x, family));
2308 }
2309
2310 /*
2311 * 0 or more than 0 is returned when validation is succeeded (either bypass
2312 * because of optional transport mode, or next index of the mathced secpath
2313 * state with the template.
2314 * -1 is returned when no matching template is found.
2315 * Otherwise "-2 - errored_index" is returned.
2316 */
2317 static inline int
2318 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2319 unsigned short family)
2320 {
2321 int idx = start;
2322
2323 if (tmpl->optional) {
2324 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2325 return start;
2326 } else
2327 start = -1;
2328 for (; idx < sp->len; idx++) {
2329 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2330 return ++idx;
2331 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2332 if (start == -1)
2333 start = -2-idx;
2334 break;
2335 }
2336 }
2337 return start;
2338 }
2339
2340 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2341 unsigned int family, int reverse)
2342 {
2343 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2344 int err;
2345
2346 if (unlikely(afinfo == NULL))
2347 return -EAFNOSUPPORT;
2348
2349 afinfo->decode_session(skb, fl, reverse);
2350 err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2351 rcu_read_unlock();
2352 return err;
2353 }
2354 EXPORT_SYMBOL(__xfrm_decode_session);
2355
2356 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2357 {
2358 for (; k < sp->len; k++) {
2359 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2360 *idxp = k;
2361 return 1;
2362 }
2363 }
2364
2365 return 0;
2366 }
2367
2368 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2369 unsigned short family)
2370 {
2371 struct net *net = dev_net(skb->dev);
2372 struct xfrm_policy *pol;
2373 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2374 int npols = 0;
2375 int xfrm_nr;
2376 int pi;
2377 int reverse;
2378 struct flowi fl;
2379 int xerr_idx = -1;
2380
2381 reverse = dir & ~XFRM_POLICY_MASK;
2382 dir &= XFRM_POLICY_MASK;
2383
2384 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2385 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2386 return 0;
2387 }
2388
2389 nf_nat_decode_session(skb, &fl, family);
2390
2391 /* First, check used SA against their selectors. */
2392 if (skb->sp) {
2393 int i;
2394
2395 for (i = skb->sp->len-1; i >= 0; i--) {
2396 struct xfrm_state *x = skb->sp->xvec[i];
2397 if (!xfrm_selector_match(&x->sel, &fl, family)) {
2398 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2399 return 0;
2400 }
2401 }
2402 }
2403
2404 pol = NULL;
2405 sk = sk_to_full_sk(sk);
2406 if (sk && sk->sk_policy[dir]) {
2407 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family);
2408 if (IS_ERR(pol)) {
2409 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2410 return 0;
2411 }
2412 }
2413
2414 if (!pol)
2415 pol = xfrm_policy_lookup(net, &fl, family, dir);
2416
2417 if (IS_ERR(pol)) {
2418 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2419 return 0;
2420 }
2421
2422 if (!pol) {
2423 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2424 xfrm_secpath_reject(xerr_idx, skb, &fl);
2425 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2426 return 0;
2427 }
2428 return 1;
2429 }
2430
2431 pol->curlft.use_time = get_seconds();
2432
2433 pols[0] = pol;
2434 npols++;
2435 #ifdef CONFIG_XFRM_SUB_POLICY
2436 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2437 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2438 &fl, family,
2439 XFRM_POLICY_IN);
2440 if (pols[1]) {
2441 if (IS_ERR(pols[1])) {
2442 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2443 return 0;
2444 }
2445 pols[1]->curlft.use_time = get_seconds();
2446 npols++;
2447 }
2448 }
2449 #endif
2450
2451 if (pol->action == XFRM_POLICY_ALLOW) {
2452 struct sec_path *sp;
2453 static struct sec_path dummy;
2454 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2455 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2456 struct xfrm_tmpl **tpp = tp;
2457 int ti = 0;
2458 int i, k;
2459
2460 if ((sp = skb->sp) == NULL)
2461 sp = &dummy;
2462
2463 for (pi = 0; pi < npols; pi++) {
2464 if (pols[pi] != pol &&
2465 pols[pi]->action != XFRM_POLICY_ALLOW) {
2466 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2467 goto reject;
2468 }
2469 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2470 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2471 goto reject_error;
2472 }
2473 for (i = 0; i < pols[pi]->xfrm_nr; i++)
2474 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2475 }
2476 xfrm_nr = ti;
2477 if (npols > 1) {
2478 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2479 tpp = stp;
2480 }
2481
2482 /* For each tunnel xfrm, find the first matching tmpl.
2483 * For each tmpl before that, find corresponding xfrm.
2484 * Order is _important_. Later we will implement
2485 * some barriers, but at the moment barriers
2486 * are implied between each two transformations.
2487 */
2488 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2489 k = xfrm_policy_ok(tpp[i], sp, k, family);
2490 if (k < 0) {
2491 if (k < -1)
2492 /* "-2 - errored_index" returned */
2493 xerr_idx = -(2+k);
2494 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2495 goto reject;
2496 }
2497 }
2498
2499 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2500 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2501 goto reject;
2502 }
2503
2504 xfrm_pols_put(pols, npols);
2505 return 1;
2506 }
2507 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2508
2509 reject:
2510 xfrm_secpath_reject(xerr_idx, skb, &fl);
2511 reject_error:
2512 xfrm_pols_put(pols, npols);
2513 return 0;
2514 }
2515 EXPORT_SYMBOL(__xfrm_policy_check);
2516
2517 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2518 {
2519 struct net *net = dev_net(skb->dev);
2520 struct flowi fl;
2521 struct dst_entry *dst;
2522 int res = 1;
2523
2524 if (xfrm_decode_session(skb, &fl, family) < 0) {
2525 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2526 return 0;
2527 }
2528
2529 skb_dst_force(skb);
2530
2531 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2532 if (IS_ERR(dst)) {
2533 res = 0;
2534 dst = NULL;
2535 }
2536 skb_dst_set(skb, dst);
2537 return res;
2538 }
2539 EXPORT_SYMBOL(__xfrm_route_forward);
2540
2541 /* Optimize later using cookies and generation ids. */
2542
2543 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2544 {
2545 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2546 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2547 * get validated by dst_ops->check on every use. We do this
2548 * because when a normal route referenced by an XFRM dst is
2549 * obsoleted we do not go looking around for all parent
2550 * referencing XFRM dsts so that we can invalidate them. It
2551 * is just too much work. Instead we make the checks here on
2552 * every use. For example:
2553 *
2554 * XFRM dst A --> IPv4 dst X
2555 *
2556 * X is the "xdst->route" of A (X is also the "dst->path" of A
2557 * in this example). If X is marked obsolete, "A" will not
2558 * notice. That's what we are validating here via the
2559 * stale_bundle() check.
2560 *
2561 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
2562 * be marked on it.
2563 * This will force stale_bundle() to fail on any xdst bundle with
2564 * this dst linked in it.
2565 */
2566 if (dst->obsolete < 0 && !stale_bundle(dst))
2567 return dst;
2568
2569 return NULL;
2570 }
2571
2572 static int stale_bundle(struct dst_entry *dst)
2573 {
2574 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2575 }
2576
2577 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2578 {
2579 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2580 dst->dev = dev_net(dev)->loopback_dev;
2581 dev_hold(dst->dev);
2582 dev_put(dev);
2583 }
2584 }
2585 EXPORT_SYMBOL(xfrm_dst_ifdown);
2586
2587 static void xfrm_link_failure(struct sk_buff *skb)
2588 {
2589 /* Impossible. Such dst must be popped before reaches point of failure. */
2590 }
2591
2592 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2593 {
2594 if (dst) {
2595 if (dst->obsolete) {
2596 dst_release(dst);
2597 dst = NULL;
2598 }
2599 }
2600 return dst;
2601 }
2602
2603 static void xfrm_init_pmtu(struct dst_entry *dst)
2604 {
2605 do {
2606 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2607 u32 pmtu, route_mtu_cached;
2608
2609 pmtu = dst_mtu(dst->child);
2610 xdst->child_mtu_cached = pmtu;
2611
2612 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2613
2614 route_mtu_cached = dst_mtu(xdst->route);
2615 xdst->route_mtu_cached = route_mtu_cached;
2616
2617 if (pmtu > route_mtu_cached)
2618 pmtu = route_mtu_cached;
2619
2620 dst_metric_set(dst, RTAX_MTU, pmtu);
2621 } while ((dst = dst->next));
2622 }
2623
2624 /* Check that the bundle accepts the flow and its components are
2625 * still valid.
2626 */
2627
2628 static int xfrm_bundle_ok(struct xfrm_dst *first)
2629 {
2630 struct dst_entry *dst = &first->u.dst;
2631 struct xfrm_dst *last;
2632 u32 mtu;
2633
2634 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2635 (dst->dev && !netif_running(dst->dev)))
2636 return 0;
2637
2638 if (dst->flags & DST_XFRM_QUEUE)
2639 return 1;
2640
2641 last = NULL;
2642
2643 do {
2644 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2645
2646 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2647 return 0;
2648 if (xdst->xfrm_genid != dst->xfrm->genid)
2649 return 0;
2650 if (xdst->num_pols > 0 &&
2651 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2652 return 0;
2653
2654 mtu = dst_mtu(dst->child);
2655 if (xdst->child_mtu_cached != mtu) {
2656 last = xdst;
2657 xdst->child_mtu_cached = mtu;
2658 }
2659
2660 if (!dst_check(xdst->route, xdst->route_cookie))
2661 return 0;
2662 mtu = dst_mtu(xdst->route);
2663 if (xdst->route_mtu_cached != mtu) {
2664 last = xdst;
2665 xdst->route_mtu_cached = mtu;
2666 }
2667
2668 dst = dst->child;
2669 } while (dst->xfrm);
2670
2671 if (likely(!last))
2672 return 1;
2673
2674 mtu = last->child_mtu_cached;
2675 for (;;) {
2676 dst = &last->u.dst;
2677
2678 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2679 if (mtu > last->route_mtu_cached)
2680 mtu = last->route_mtu_cached;
2681 dst_metric_set(dst, RTAX_MTU, mtu);
2682
2683 if (last == first)
2684 break;
2685
2686 last = (struct xfrm_dst *)last->u.dst.next;
2687 last->child_mtu_cached = mtu;
2688 }
2689
2690 return 1;
2691 }
2692
2693 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2694 {
2695 return dst_metric_advmss(dst->path);
2696 }
2697
2698 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2699 {
2700 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2701
2702 return mtu ? : dst_mtu(dst->path);
2703 }
2704
2705 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2706 const void *daddr)
2707 {
2708 const struct dst_entry *path = dst->path;
2709
2710 for (; dst != path; dst = dst->child) {
2711 const struct xfrm_state *xfrm = dst->xfrm;
2712
2713 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2714 continue;
2715 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2716 daddr = xfrm->coaddr;
2717 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2718 daddr = &xfrm->id.daddr;
2719 }
2720 return daddr;
2721 }
2722
2723 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2724 struct sk_buff *skb,
2725 const void *daddr)
2726 {
2727 const struct dst_entry *path = dst->path;
2728
2729 if (!skb)
2730 daddr = xfrm_get_dst_nexthop(dst, daddr);
2731 return path->ops->neigh_lookup(path, skb, daddr);
2732 }
2733
2734 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2735 {
2736 const struct dst_entry *path = dst->path;
2737
2738 daddr = xfrm_get_dst_nexthop(dst, daddr);
2739 path->ops->confirm_neigh(path, daddr);
2740 }
2741
2742 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2743 {
2744 int err = 0;
2745
2746 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2747 return -EAFNOSUPPORT;
2748
2749 spin_lock(&xfrm_policy_afinfo_lock);
2750 if (unlikely(xfrm_policy_afinfo[family] != NULL))
2751 err = -EEXIST;
2752 else {
2753 struct dst_ops *dst_ops = afinfo->dst_ops;
2754 if (likely(dst_ops->kmem_cachep == NULL))
2755 dst_ops->kmem_cachep = xfrm_dst_cache;
2756 if (likely(dst_ops->check == NULL))
2757 dst_ops->check = xfrm_dst_check;
2758 if (likely(dst_ops->default_advmss == NULL))
2759 dst_ops->default_advmss = xfrm_default_advmss;
2760 if (likely(dst_ops->mtu == NULL))
2761 dst_ops->mtu = xfrm_mtu;
2762 if (likely(dst_ops->negative_advice == NULL))
2763 dst_ops->negative_advice = xfrm_negative_advice;
2764 if (likely(dst_ops->link_failure == NULL))
2765 dst_ops->link_failure = xfrm_link_failure;
2766 if (likely(dst_ops->neigh_lookup == NULL))
2767 dst_ops->neigh_lookup = xfrm_neigh_lookup;
2768 if (likely(!dst_ops->confirm_neigh))
2769 dst_ops->confirm_neigh = xfrm_confirm_neigh;
2770 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2771 }
2772 spin_unlock(&xfrm_policy_afinfo_lock);
2773
2774 return err;
2775 }
2776 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2777
2778 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2779 {
2780 struct dst_ops *dst_ops = afinfo->dst_ops;
2781 int i;
2782
2783 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2784 if (xfrm_policy_afinfo[i] != afinfo)
2785 continue;
2786 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2787 break;
2788 }
2789
2790 synchronize_rcu();
2791
2792 dst_ops->kmem_cachep = NULL;
2793 dst_ops->check = NULL;
2794 dst_ops->negative_advice = NULL;
2795 dst_ops->link_failure = NULL;
2796 }
2797 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2798
2799 #ifdef CONFIG_XFRM_STATISTICS
2800 static int __net_init xfrm_statistics_init(struct net *net)
2801 {
2802 int rv;
2803 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2804 if (!net->mib.xfrm_statistics)
2805 return -ENOMEM;
2806 rv = xfrm_proc_init(net);
2807 if (rv < 0)
2808 free_percpu(net->mib.xfrm_statistics);
2809 return rv;
2810 }
2811
2812 static void xfrm_statistics_fini(struct net *net)
2813 {
2814 xfrm_proc_fini(net);
2815 free_percpu(net->mib.xfrm_statistics);
2816 }
2817 #else
2818 static int __net_init xfrm_statistics_init(struct net *net)
2819 {
2820 return 0;
2821 }
2822
2823 static void xfrm_statistics_fini(struct net *net)
2824 {
2825 }
2826 #endif
2827
2828 static int __net_init xfrm_policy_init(struct net *net)
2829 {
2830 unsigned int hmask, sz;
2831 int dir;
2832
2833 if (net_eq(net, &init_net))
2834 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2835 sizeof(struct xfrm_dst),
2836 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2837 NULL);
2838
2839 hmask = 8 - 1;
2840 sz = (hmask+1) * sizeof(struct hlist_head);
2841
2842 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2843 if (!net->xfrm.policy_byidx)
2844 goto out_byidx;
2845 net->xfrm.policy_idx_hmask = hmask;
2846
2847 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2848 struct xfrm_policy_hash *htab;
2849
2850 net->xfrm.policy_count[dir] = 0;
2851 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2852 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2853
2854 htab = &net->xfrm.policy_bydst[dir];
2855 htab->table = xfrm_hash_alloc(sz);
2856 if (!htab->table)
2857 goto out_bydst;
2858 htab->hmask = hmask;
2859 htab->dbits4 = 32;
2860 htab->sbits4 = 32;
2861 htab->dbits6 = 128;
2862 htab->sbits6 = 128;
2863 }
2864 net->xfrm.policy_hthresh.lbits4 = 32;
2865 net->xfrm.policy_hthresh.rbits4 = 32;
2866 net->xfrm.policy_hthresh.lbits6 = 128;
2867 net->xfrm.policy_hthresh.rbits6 = 128;
2868
2869 seqlock_init(&net->xfrm.policy_hthresh.lock);
2870
2871 INIT_LIST_HEAD(&net->xfrm.policy_all);
2872 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2873 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2874 if (net_eq(net, &init_net))
2875 xfrm_dev_init();
2876 return 0;
2877
2878 out_bydst:
2879 for (dir--; dir >= 0; dir--) {
2880 struct xfrm_policy_hash *htab;
2881
2882 htab = &net->xfrm.policy_bydst[dir];
2883 xfrm_hash_free(htab->table, sz);
2884 }
2885 xfrm_hash_free(net->xfrm.policy_byidx, sz);
2886 out_byidx:
2887 return -ENOMEM;
2888 }
2889
2890 static void xfrm_policy_fini(struct net *net)
2891 {
2892 unsigned int sz;
2893 int dir;
2894
2895 flush_work(&net->xfrm.policy_hash_work);
2896 #ifdef CONFIG_XFRM_SUB_POLICY
2897 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
2898 #endif
2899 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
2900
2901 WARN_ON(!list_empty(&net->xfrm.policy_all));
2902
2903 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2904 struct xfrm_policy_hash *htab;
2905
2906 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2907
2908 htab = &net->xfrm.policy_bydst[dir];
2909 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2910 WARN_ON(!hlist_empty(htab->table));
2911 xfrm_hash_free(htab->table, sz);
2912 }
2913
2914 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2915 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2916 xfrm_hash_free(net->xfrm.policy_byidx, sz);
2917 }
2918
2919 static int __net_init xfrm_net_init(struct net *net)
2920 {
2921 int rv;
2922
2923 /* Initialize the per-net locks here */
2924 spin_lock_init(&net->xfrm.xfrm_state_lock);
2925 spin_lock_init(&net->xfrm.xfrm_policy_lock);
2926 mutex_init(&net->xfrm.xfrm_cfg_mutex);
2927
2928 rv = xfrm_statistics_init(net);
2929 if (rv < 0)
2930 goto out_statistics;
2931 rv = xfrm_state_init(net);
2932 if (rv < 0)
2933 goto out_state;
2934 rv = xfrm_policy_init(net);
2935 if (rv < 0)
2936 goto out_policy;
2937 rv = xfrm_sysctl_init(net);
2938 if (rv < 0)
2939 goto out_sysctl;
2940
2941 return 0;
2942
2943 out_sysctl:
2944 xfrm_policy_fini(net);
2945 out_policy:
2946 xfrm_state_fini(net);
2947 out_state:
2948 xfrm_statistics_fini(net);
2949 out_statistics:
2950 return rv;
2951 }
2952
2953 static void __net_exit xfrm_net_exit(struct net *net)
2954 {
2955 xfrm_sysctl_fini(net);
2956 xfrm_policy_fini(net);
2957 xfrm_state_fini(net);
2958 xfrm_statistics_fini(net);
2959 }
2960
2961 static struct pernet_operations __net_initdata xfrm_net_ops = {
2962 .init = xfrm_net_init,
2963 .exit = xfrm_net_exit,
2964 };
2965
2966 void __init xfrm_init(void)
2967 {
2968 int i;
2969
2970 xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work),
2971 GFP_KERNEL);
2972 BUG_ON(!xfrm_pcpu_work);
2973
2974 for (i = 0; i < NR_CPUS; i++)
2975 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn);
2976
2977 register_pernet_subsys(&xfrm_net_ops);
2978 seqcount_init(&xfrm_policy_hash_generation);
2979 xfrm_input_init();
2980 }
2981
2982 #ifdef CONFIG_AUDITSYSCALL
2983 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2984 struct audit_buffer *audit_buf)
2985 {
2986 struct xfrm_sec_ctx *ctx = xp->security;
2987 struct xfrm_selector *sel = &xp->selector;
2988
2989 if (ctx)
2990 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2991 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2992
2993 switch (sel->family) {
2994 case AF_INET:
2995 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2996 if (sel->prefixlen_s != 32)
2997 audit_log_format(audit_buf, " src_prefixlen=%d",
2998 sel->prefixlen_s);
2999 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3000 if (sel->prefixlen_d != 32)
3001 audit_log_format(audit_buf, " dst_prefixlen=%d",
3002 sel->prefixlen_d);
3003 break;
3004 case AF_INET6:
3005 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3006 if (sel->prefixlen_s != 128)
3007 audit_log_format(audit_buf, " src_prefixlen=%d",
3008 sel->prefixlen_s);
3009 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3010 if (sel->prefixlen_d != 128)
3011 audit_log_format(audit_buf, " dst_prefixlen=%d",
3012 sel->prefixlen_d);
3013 break;
3014 }
3015 }
3016
3017 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3018 {
3019 struct audit_buffer *audit_buf;
3020
3021 audit_buf = xfrm_audit_start("SPD-add");
3022 if (audit_buf == NULL)
3023 return;
3024 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3025 audit_log_format(audit_buf, " res=%u", result);
3026 xfrm_audit_common_policyinfo(xp, audit_buf);
3027 audit_log_end(audit_buf);
3028 }
3029 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3030
3031 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3032 bool task_valid)
3033 {
3034 struct audit_buffer *audit_buf;
3035
3036 audit_buf = xfrm_audit_start("SPD-delete");
3037 if (audit_buf == NULL)
3038 return;
3039 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3040 audit_log_format(audit_buf, " res=%u", result);
3041 xfrm_audit_common_policyinfo(xp, audit_buf);
3042 audit_log_end(audit_buf);
3043 }
3044 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3045 #endif
3046
3047 #ifdef CONFIG_XFRM_MIGRATE
3048 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3049 const struct xfrm_selector *sel_tgt)
3050 {
3051 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3052 if (sel_tgt->family == sel_cmp->family &&
3053 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3054 sel_cmp->family) &&
3055 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3056 sel_cmp->family) &&
3057 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3058 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3059 return true;
3060 }
3061 } else {
3062 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3063 return true;
3064 }
3065 }
3066 return false;
3067 }
3068
3069 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3070 u8 dir, u8 type, struct net *net)
3071 {
3072 struct xfrm_policy *pol, *ret = NULL;
3073 struct hlist_head *chain;
3074 u32 priority = ~0U;
3075
3076 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3077 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3078 hlist_for_each_entry(pol, chain, bydst) {
3079 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3080 pol->type == type) {
3081 ret = pol;
3082 priority = ret->priority;
3083 break;
3084 }
3085 }
3086 chain = &net->xfrm.policy_inexact[dir];
3087 hlist_for_each_entry(pol, chain, bydst) {
3088 if ((pol->priority >= priority) && ret)
3089 break;
3090
3091 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3092 pol->type == type) {
3093 ret = pol;
3094 break;
3095 }
3096 }
3097
3098 xfrm_pol_hold(ret);
3099
3100 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3101
3102 return ret;
3103 }
3104
3105 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3106 {
3107 int match = 0;
3108
3109 if (t->mode == m->mode && t->id.proto == m->proto &&
3110 (m->reqid == 0 || t->reqid == m->reqid)) {
3111 switch (t->mode) {
3112 case XFRM_MODE_TUNNEL:
3113 case XFRM_MODE_BEET:
3114 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3115 m->old_family) &&
3116 xfrm_addr_equal(&t->saddr, &m->old_saddr,
3117 m->old_family)) {
3118 match = 1;
3119 }
3120 break;
3121 case XFRM_MODE_TRANSPORT:
3122 /* in case of transport mode, template does not store
3123 any IP addresses, hence we just compare mode and
3124 protocol */
3125 match = 1;
3126 break;
3127 default:
3128 break;
3129 }
3130 }
3131 return match;
3132 }
3133
3134 /* update endpoint address(es) of template(s) */
3135 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3136 struct xfrm_migrate *m, int num_migrate)
3137 {
3138 struct xfrm_migrate *mp;
3139 int i, j, n = 0;
3140
3141 write_lock_bh(&pol->lock);
3142 if (unlikely(pol->walk.dead)) {
3143 /* target policy has been deleted */
3144 write_unlock_bh(&pol->lock);
3145 return -ENOENT;
3146 }
3147
3148 for (i = 0; i < pol->xfrm_nr; i++) {
3149 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3150 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3151 continue;
3152 n++;
3153 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3154 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3155 continue;
3156 /* update endpoints */
3157 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3158 sizeof(pol->xfrm_vec[i].id.daddr));
3159 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3160 sizeof(pol->xfrm_vec[i].saddr));
3161 pol->xfrm_vec[i].encap_family = mp->new_family;
3162 /* flush bundles */
3163 atomic_inc(&pol->genid);
3164 }
3165 }
3166
3167 write_unlock_bh(&pol->lock);
3168
3169 if (!n)
3170 return -ENODATA;
3171
3172 return 0;
3173 }
3174
3175 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3176 {
3177 int i, j;
3178
3179 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3180 return -EINVAL;
3181
3182 for (i = 0; i < num_migrate; i++) {
3183 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3184 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3185 return -EINVAL;
3186
3187 /* check if there is any duplicated entry */
3188 for (j = i + 1; j < num_migrate; j++) {
3189 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3190 sizeof(m[i].old_daddr)) &&
3191 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3192 sizeof(m[i].old_saddr)) &&
3193 m[i].proto == m[j].proto &&
3194 m[i].mode == m[j].mode &&
3195 m[i].reqid == m[j].reqid &&
3196 m[i].old_family == m[j].old_family)
3197 return -EINVAL;
3198 }
3199 }
3200
3201 return 0;
3202 }
3203
3204 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3205 struct xfrm_migrate *m, int num_migrate,
3206 struct xfrm_kmaddress *k, struct net *net,
3207 struct xfrm_encap_tmpl *encap)
3208 {
3209 int i, err, nx_cur = 0, nx_new = 0;
3210 struct xfrm_policy *pol = NULL;
3211 struct xfrm_state *x, *xc;
3212 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3213 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3214 struct xfrm_migrate *mp;
3215
3216 /* Stage 0 - sanity checks */
3217 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3218 goto out;
3219
3220 if (dir >= XFRM_POLICY_MAX) {
3221 err = -EINVAL;
3222 goto out;
3223 }
3224
3225 /* Stage 1 - find policy */
3226 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3227 err = -ENOENT;
3228 goto out;
3229 }
3230
3231 /* Stage 2 - find and update state(s) */
3232 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3233 if ((x = xfrm_migrate_state_find(mp, net))) {
3234 x_cur[nx_cur] = x;
3235 nx_cur++;
3236 xc = xfrm_state_migrate(x, mp, encap);
3237 if (xc) {
3238 x_new[nx_new] = xc;
3239 nx_new++;
3240 } else {
3241 err = -ENODATA;
3242 goto restore_state;
3243 }
3244 }
3245 }
3246
3247 /* Stage 3 - update policy */
3248 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3249 goto restore_state;
3250
3251 /* Stage 4 - delete old state(s) */
3252 if (nx_cur) {
3253 xfrm_states_put(x_cur, nx_cur);
3254 xfrm_states_delete(x_cur, nx_cur);
3255 }
3256
3257 /* Stage 5 - announce */
3258 km_migrate(sel, dir, type, m, num_migrate, k, encap);
3259
3260 xfrm_pol_put(pol);
3261
3262 return 0;
3263 out:
3264 return err;
3265
3266 restore_state:
3267 if (pol)
3268 xfrm_pol_put(pol);
3269 if (nx_cur)
3270 xfrm_states_put(x_cur, nx_cur);
3271 if (nx_new)
3272 xfrm_states_delete(x_new, nx_new);
3273
3274 return err;
3275 }
3276 EXPORT_SYMBOL(xfrm_migrate);
3277 #endif
Linux with added FPC-III support