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[XFRM]: Assorted IPsec fixups
[deliverable/linux.git] / net / xfrm / xfrm_policy.c
1 /*
2 * xfrm_policy.c
3 *
4 * Changes:
5 * Mitsuru KANDA @USAGI
6 * Kazunori MIYAZAWA @USAGI
7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8 * IPv6 support
9 * Kazunori MIYAZAWA @USAGI
10 * YOSHIFUJI Hideaki
11 * Split up af-specific portion
12 * Derek Atkins <derek@ihtfp.com> Add the post_input processor
13 *
14 */
15
16 #include <linux/err.h>
17 #include <linux/slab.h>
18 #include <linux/kmod.h>
19 #include <linux/list.h>
20 #include <linux/spinlock.h>
21 #include <linux/workqueue.h>
22 #include <linux/notifier.h>
23 #include <linux/netdevice.h>
24 #include <linux/netfilter.h>
25 #include <linux/module.h>
26 #include <linux/cache.h>
27 #include <linux/audit.h>
28 #include <net/dst.h>
29 #include <net/xfrm.h>
30 #include <net/ip.h>
31 #ifdef CONFIG_XFRM_STATISTICS
32 #include <net/snmp.h>
33 #endif
34
35 #include "xfrm_hash.h"
36
37 int sysctl_xfrm_larval_drop __read_mostly;
38
39 #ifdef CONFIG_XFRM_STATISTICS
40 DEFINE_SNMP_STAT(struct linux_xfrm_mib, xfrm_statistics) __read_mostly;
41 EXPORT_SYMBOL(xfrm_statistics);
42 #endif
43
44 DEFINE_MUTEX(xfrm_cfg_mutex);
45 EXPORT_SYMBOL(xfrm_cfg_mutex);
46
47 static DEFINE_RWLOCK(xfrm_policy_lock);
48
49 unsigned int xfrm_policy_count[XFRM_POLICY_MAX*2];
50 EXPORT_SYMBOL(xfrm_policy_count);
51
52 static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
53 static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
54
55 static struct kmem_cache *xfrm_dst_cache __read_mostly;
56
57 static struct work_struct xfrm_policy_gc_work;
58 static HLIST_HEAD(xfrm_policy_gc_list);
59 static DEFINE_SPINLOCK(xfrm_policy_gc_lock);
60
61 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
62 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
63 static void xfrm_init_pmtu(struct dst_entry *dst);
64
65 static inline int
66 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
67 {
68 return addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
69 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
70 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
71 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
72 (fl->proto == sel->proto || !sel->proto) &&
73 (fl->oif == sel->ifindex || !sel->ifindex);
74 }
75
76 static inline int
77 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
78 {
79 return addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
80 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
81 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
82 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
83 (fl->proto == sel->proto || !sel->proto) &&
84 (fl->oif == sel->ifindex || !sel->ifindex);
85 }
86
87 int xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
88 unsigned short family)
89 {
90 switch (family) {
91 case AF_INET:
92 return __xfrm4_selector_match(sel, fl);
93 case AF_INET6:
94 return __xfrm6_selector_match(sel, fl);
95 }
96 return 0;
97 }
98
99 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
100 int family)
101 {
102 xfrm_address_t *saddr = &x->props.saddr;
103 xfrm_address_t *daddr = &x->id.daddr;
104 struct xfrm_policy_afinfo *afinfo;
105 struct dst_entry *dst;
106
107 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR)
108 saddr = x->coaddr;
109 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR)
110 daddr = x->coaddr;
111
112 afinfo = xfrm_policy_get_afinfo(family);
113 if (unlikely(afinfo == NULL))
114 return ERR_PTR(-EAFNOSUPPORT);
115
116 dst = afinfo->dst_lookup(tos, saddr, daddr);
117 xfrm_policy_put_afinfo(afinfo);
118 return dst;
119 }
120
121 static inline unsigned long make_jiffies(long secs)
122 {
123 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
124 return MAX_SCHEDULE_TIMEOUT-1;
125 else
126 return secs*HZ;
127 }
128
129 static void xfrm_policy_timer(unsigned long data)
130 {
131 struct xfrm_policy *xp = (struct xfrm_policy*)data;
132 unsigned long now = get_seconds();
133 long next = LONG_MAX;
134 int warn = 0;
135 int dir;
136
137 read_lock(&xp->lock);
138
139 if (xp->dead)
140 goto out;
141
142 dir = xfrm_policy_id2dir(xp->index);
143
144 if (xp->lft.hard_add_expires_seconds) {
145 long tmo = xp->lft.hard_add_expires_seconds +
146 xp->curlft.add_time - now;
147 if (tmo <= 0)
148 goto expired;
149 if (tmo < next)
150 next = tmo;
151 }
152 if (xp->lft.hard_use_expires_seconds) {
153 long tmo = xp->lft.hard_use_expires_seconds +
154 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
155 if (tmo <= 0)
156 goto expired;
157 if (tmo < next)
158 next = tmo;
159 }
160 if (xp->lft.soft_add_expires_seconds) {
161 long tmo = xp->lft.soft_add_expires_seconds +
162 xp->curlft.add_time - now;
163 if (tmo <= 0) {
164 warn = 1;
165 tmo = XFRM_KM_TIMEOUT;
166 }
167 if (tmo < next)
168 next = tmo;
169 }
170 if (xp->lft.soft_use_expires_seconds) {
171 long tmo = xp->lft.soft_use_expires_seconds +
172 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
173 if (tmo <= 0) {
174 warn = 1;
175 tmo = XFRM_KM_TIMEOUT;
176 }
177 if (tmo < next)
178 next = tmo;
179 }
180
181 if (warn)
182 km_policy_expired(xp, dir, 0, 0);
183 if (next != LONG_MAX &&
184 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
185 xfrm_pol_hold(xp);
186
187 out:
188 read_unlock(&xp->lock);
189 xfrm_pol_put(xp);
190 return;
191
192 expired:
193 read_unlock(&xp->lock);
194 if (!xfrm_policy_delete(xp, dir))
195 km_policy_expired(xp, dir, 1, 0);
196 xfrm_pol_put(xp);
197 }
198
199
200 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
201 * SPD calls.
202 */
203
204 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp)
205 {
206 struct xfrm_policy *policy;
207
208 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
209
210 if (policy) {
211 INIT_HLIST_NODE(&policy->bydst);
212 INIT_HLIST_NODE(&policy->byidx);
213 rwlock_init(&policy->lock);
214 atomic_set(&policy->refcnt, 1);
215 setup_timer(&policy->timer, xfrm_policy_timer,
216 (unsigned long)policy);
217 }
218 return policy;
219 }
220 EXPORT_SYMBOL(xfrm_policy_alloc);
221
222 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
223
224 void __xfrm_policy_destroy(struct xfrm_policy *policy)
225 {
226 BUG_ON(!policy->dead);
227
228 BUG_ON(policy->bundles);
229
230 if (del_timer(&policy->timer))
231 BUG();
232
233 security_xfrm_policy_free(policy);
234 kfree(policy);
235 }
236 EXPORT_SYMBOL(__xfrm_policy_destroy);
237
238 static void xfrm_policy_gc_kill(struct xfrm_policy *policy)
239 {
240 struct dst_entry *dst;
241
242 while ((dst = policy->bundles) != NULL) {
243 policy->bundles = dst->next;
244 dst_free(dst);
245 }
246
247 if (del_timer(&policy->timer))
248 atomic_dec(&policy->refcnt);
249
250 if (atomic_read(&policy->refcnt) > 1)
251 flow_cache_flush();
252
253 xfrm_pol_put(policy);
254 }
255
256 static void xfrm_policy_gc_task(struct work_struct *work)
257 {
258 struct xfrm_policy *policy;
259 struct hlist_node *entry, *tmp;
260 struct hlist_head gc_list;
261
262 spin_lock_bh(&xfrm_policy_gc_lock);
263 gc_list.first = xfrm_policy_gc_list.first;
264 INIT_HLIST_HEAD(&xfrm_policy_gc_list);
265 spin_unlock_bh(&xfrm_policy_gc_lock);
266
267 hlist_for_each_entry_safe(policy, entry, tmp, &gc_list, bydst)
268 xfrm_policy_gc_kill(policy);
269 }
270
271 /* Rule must be locked. Release descentant resources, announce
272 * entry dead. The rule must be unlinked from lists to the moment.
273 */
274
275 static void xfrm_policy_kill(struct xfrm_policy *policy)
276 {
277 int dead;
278
279 write_lock_bh(&policy->lock);
280 dead = policy->dead;
281 policy->dead = 1;
282 write_unlock_bh(&policy->lock);
283
284 if (unlikely(dead)) {
285 WARN_ON(1);
286 return;
287 }
288
289 spin_lock(&xfrm_policy_gc_lock);
290 hlist_add_head(&policy->bydst, &xfrm_policy_gc_list);
291 spin_unlock(&xfrm_policy_gc_lock);
292
293 schedule_work(&xfrm_policy_gc_work);
294 }
295
296 struct xfrm_policy_hash {
297 struct hlist_head *table;
298 unsigned int hmask;
299 };
300
301 static struct hlist_head xfrm_policy_inexact[XFRM_POLICY_MAX*2];
302 static struct xfrm_policy_hash xfrm_policy_bydst[XFRM_POLICY_MAX*2] __read_mostly;
303 static struct hlist_head *xfrm_policy_byidx __read_mostly;
304 static unsigned int xfrm_idx_hmask __read_mostly;
305 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
306
307 static inline unsigned int idx_hash(u32 index)
308 {
309 return __idx_hash(index, xfrm_idx_hmask);
310 }
311
312 static struct hlist_head *policy_hash_bysel(struct xfrm_selector *sel, unsigned short family, int dir)
313 {
314 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
315 unsigned int hash = __sel_hash(sel, family, hmask);
316
317 return (hash == hmask + 1 ?
318 &xfrm_policy_inexact[dir] :
319 xfrm_policy_bydst[dir].table + hash);
320 }
321
322 static struct hlist_head *policy_hash_direct(xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, int dir)
323 {
324 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
325 unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
326
327 return xfrm_policy_bydst[dir].table + hash;
328 }
329
330 static void xfrm_dst_hash_transfer(struct hlist_head *list,
331 struct hlist_head *ndsttable,
332 unsigned int nhashmask)
333 {
334 struct hlist_node *entry, *tmp;
335 struct xfrm_policy *pol;
336
337 hlist_for_each_entry_safe(pol, entry, tmp, list, bydst) {
338 unsigned int h;
339
340 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
341 pol->family, nhashmask);
342 hlist_add_head(&pol->bydst, ndsttable+h);
343 }
344 }
345
346 static void xfrm_idx_hash_transfer(struct hlist_head *list,
347 struct hlist_head *nidxtable,
348 unsigned int nhashmask)
349 {
350 struct hlist_node *entry, *tmp;
351 struct xfrm_policy *pol;
352
353 hlist_for_each_entry_safe(pol, entry, tmp, list, byidx) {
354 unsigned int h;
355
356 h = __idx_hash(pol->index, nhashmask);
357 hlist_add_head(&pol->byidx, nidxtable+h);
358 }
359 }
360
361 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
362 {
363 return ((old_hmask + 1) << 1) - 1;
364 }
365
366 static void xfrm_bydst_resize(int dir)
367 {
368 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
369 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
370 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
371 struct hlist_head *odst = xfrm_policy_bydst[dir].table;
372 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
373 int i;
374
375 if (!ndst)
376 return;
377
378 write_lock_bh(&xfrm_policy_lock);
379
380 for (i = hmask; i >= 0; i--)
381 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
382
383 xfrm_policy_bydst[dir].table = ndst;
384 xfrm_policy_bydst[dir].hmask = nhashmask;
385
386 write_unlock_bh(&xfrm_policy_lock);
387
388 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
389 }
390
391 static void xfrm_byidx_resize(int total)
392 {
393 unsigned int hmask = xfrm_idx_hmask;
394 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
395 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
396 struct hlist_head *oidx = xfrm_policy_byidx;
397 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
398 int i;
399
400 if (!nidx)
401 return;
402
403 write_lock_bh(&xfrm_policy_lock);
404
405 for (i = hmask; i >= 0; i--)
406 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
407
408 xfrm_policy_byidx = nidx;
409 xfrm_idx_hmask = nhashmask;
410
411 write_unlock_bh(&xfrm_policy_lock);
412
413 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
414 }
415
416 static inline int xfrm_bydst_should_resize(int dir, int *total)
417 {
418 unsigned int cnt = xfrm_policy_count[dir];
419 unsigned int hmask = xfrm_policy_bydst[dir].hmask;
420
421 if (total)
422 *total += cnt;
423
424 if ((hmask + 1) < xfrm_policy_hashmax &&
425 cnt > hmask)
426 return 1;
427
428 return 0;
429 }
430
431 static inline int xfrm_byidx_should_resize(int total)
432 {
433 unsigned int hmask = xfrm_idx_hmask;
434
435 if ((hmask + 1) < xfrm_policy_hashmax &&
436 total > hmask)
437 return 1;
438
439 return 0;
440 }
441
442 void xfrm_spd_getinfo(struct xfrmk_spdinfo *si)
443 {
444 read_lock_bh(&xfrm_policy_lock);
445 si->incnt = xfrm_policy_count[XFRM_POLICY_IN];
446 si->outcnt = xfrm_policy_count[XFRM_POLICY_OUT];
447 si->fwdcnt = xfrm_policy_count[XFRM_POLICY_FWD];
448 si->inscnt = xfrm_policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
449 si->outscnt = xfrm_policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
450 si->fwdscnt = xfrm_policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
451 si->spdhcnt = xfrm_idx_hmask;
452 si->spdhmcnt = xfrm_policy_hashmax;
453 read_unlock_bh(&xfrm_policy_lock);
454 }
455 EXPORT_SYMBOL(xfrm_spd_getinfo);
456
457 static DEFINE_MUTEX(hash_resize_mutex);
458 static void xfrm_hash_resize(struct work_struct *__unused)
459 {
460 int dir, total;
461
462 mutex_lock(&hash_resize_mutex);
463
464 total = 0;
465 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
466 if (xfrm_bydst_should_resize(dir, &total))
467 xfrm_bydst_resize(dir);
468 }
469 if (xfrm_byidx_should_resize(total))
470 xfrm_byidx_resize(total);
471
472 mutex_unlock(&hash_resize_mutex);
473 }
474
475 static DECLARE_WORK(xfrm_hash_work, xfrm_hash_resize);
476
477 /* Generate new index... KAME seems to generate them ordered by cost
478 * of an absolute inpredictability of ordering of rules. This will not pass. */
479 static u32 xfrm_gen_index(u8 type, int dir)
480 {
481 static u32 idx_generator;
482
483 for (;;) {
484 struct hlist_node *entry;
485 struct hlist_head *list;
486 struct xfrm_policy *p;
487 u32 idx;
488 int found;
489
490 idx = (idx_generator | dir);
491 idx_generator += 8;
492 if (idx == 0)
493 idx = 8;
494 list = xfrm_policy_byidx + idx_hash(idx);
495 found = 0;
496 hlist_for_each_entry(p, entry, list, byidx) {
497 if (p->index == idx) {
498 found = 1;
499 break;
500 }
501 }
502 if (!found)
503 return idx;
504 }
505 }
506
507 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
508 {
509 u32 *p1 = (u32 *) s1;
510 u32 *p2 = (u32 *) s2;
511 int len = sizeof(struct xfrm_selector) / sizeof(u32);
512 int i;
513
514 for (i = 0; i < len; i++) {
515 if (p1[i] != p2[i])
516 return 1;
517 }
518
519 return 0;
520 }
521
522 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
523 {
524 struct xfrm_policy *pol;
525 struct xfrm_policy *delpol;
526 struct hlist_head *chain;
527 struct hlist_node *entry, *newpos;
528 struct dst_entry *gc_list;
529
530 write_lock_bh(&xfrm_policy_lock);
531 chain = policy_hash_bysel(&policy->selector, policy->family, dir);
532 delpol = NULL;
533 newpos = NULL;
534 hlist_for_each_entry(pol, entry, chain, bydst) {
535 if (pol->type == policy->type &&
536 !selector_cmp(&pol->selector, &policy->selector) &&
537 xfrm_sec_ctx_match(pol->security, policy->security) &&
538 !WARN_ON(delpol)) {
539 if (excl) {
540 write_unlock_bh(&xfrm_policy_lock);
541 return -EEXIST;
542 }
543 delpol = pol;
544 if (policy->priority > pol->priority)
545 continue;
546 } else if (policy->priority >= pol->priority) {
547 newpos = &pol->bydst;
548 continue;
549 }
550 if (delpol)
551 break;
552 }
553 if (newpos)
554 hlist_add_after(newpos, &policy->bydst);
555 else
556 hlist_add_head(&policy->bydst, chain);
557 xfrm_pol_hold(policy);
558 xfrm_policy_count[dir]++;
559 atomic_inc(&flow_cache_genid);
560 if (delpol) {
561 hlist_del(&delpol->bydst);
562 hlist_del(&delpol->byidx);
563 xfrm_policy_count[dir]--;
564 }
565 policy->index = delpol ? delpol->index : xfrm_gen_index(policy->type, dir);
566 hlist_add_head(&policy->byidx, xfrm_policy_byidx+idx_hash(policy->index));
567 policy->curlft.add_time = get_seconds();
568 policy->curlft.use_time = 0;
569 if (!mod_timer(&policy->timer, jiffies + HZ))
570 xfrm_pol_hold(policy);
571 write_unlock_bh(&xfrm_policy_lock);
572
573 if (delpol)
574 xfrm_policy_kill(delpol);
575 else if (xfrm_bydst_should_resize(dir, NULL))
576 schedule_work(&xfrm_hash_work);
577
578 read_lock_bh(&xfrm_policy_lock);
579 gc_list = NULL;
580 entry = &policy->bydst;
581 hlist_for_each_entry_continue(policy, entry, bydst) {
582 struct dst_entry *dst;
583
584 write_lock(&policy->lock);
585 dst = policy->bundles;
586 if (dst) {
587 struct dst_entry *tail = dst;
588 while (tail->next)
589 tail = tail->next;
590 tail->next = gc_list;
591 gc_list = dst;
592
593 policy->bundles = NULL;
594 }
595 write_unlock(&policy->lock);
596 }
597 read_unlock_bh(&xfrm_policy_lock);
598
599 while (gc_list) {
600 struct dst_entry *dst = gc_list;
601
602 gc_list = dst->next;
603 dst_free(dst);
604 }
605
606 return 0;
607 }
608 EXPORT_SYMBOL(xfrm_policy_insert);
609
610 struct xfrm_policy *xfrm_policy_bysel_ctx(u8 type, int dir,
611 struct xfrm_selector *sel,
612 struct xfrm_sec_ctx *ctx, int delete,
613 int *err)
614 {
615 struct xfrm_policy *pol, *ret;
616 struct hlist_head *chain;
617 struct hlist_node *entry;
618
619 *err = 0;
620 write_lock_bh(&xfrm_policy_lock);
621 chain = policy_hash_bysel(sel, sel->family, dir);
622 ret = NULL;
623 hlist_for_each_entry(pol, entry, chain, bydst) {
624 if (pol->type == type &&
625 !selector_cmp(sel, &pol->selector) &&
626 xfrm_sec_ctx_match(ctx, pol->security)) {
627 xfrm_pol_hold(pol);
628 if (delete) {
629 *err = security_xfrm_policy_delete(pol);
630 if (*err) {
631 write_unlock_bh(&xfrm_policy_lock);
632 return pol;
633 }
634 hlist_del(&pol->bydst);
635 hlist_del(&pol->byidx);
636 xfrm_policy_count[dir]--;
637 }
638 ret = pol;
639 break;
640 }
641 }
642 write_unlock_bh(&xfrm_policy_lock);
643
644 if (ret && delete) {
645 atomic_inc(&flow_cache_genid);
646 xfrm_policy_kill(ret);
647 }
648 return ret;
649 }
650 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
651
652 struct xfrm_policy *xfrm_policy_byid(u8 type, int dir, u32 id, int delete,
653 int *err)
654 {
655 struct xfrm_policy *pol, *ret;
656 struct hlist_head *chain;
657 struct hlist_node *entry;
658
659 *err = -ENOENT;
660 if (xfrm_policy_id2dir(id) != dir)
661 return NULL;
662
663 *err = 0;
664 write_lock_bh(&xfrm_policy_lock);
665 chain = xfrm_policy_byidx + idx_hash(id);
666 ret = NULL;
667 hlist_for_each_entry(pol, entry, chain, byidx) {
668 if (pol->type == type && pol->index == id) {
669 xfrm_pol_hold(pol);
670 if (delete) {
671 *err = security_xfrm_policy_delete(pol);
672 if (*err) {
673 write_unlock_bh(&xfrm_policy_lock);
674 return pol;
675 }
676 hlist_del(&pol->bydst);
677 hlist_del(&pol->byidx);
678 xfrm_policy_count[dir]--;
679 }
680 ret = pol;
681 break;
682 }
683 }
684 write_unlock_bh(&xfrm_policy_lock);
685
686 if (ret && delete) {
687 atomic_inc(&flow_cache_genid);
688 xfrm_policy_kill(ret);
689 }
690 return ret;
691 }
692 EXPORT_SYMBOL(xfrm_policy_byid);
693
694 #ifdef CONFIG_SECURITY_NETWORK_XFRM
695 static inline int
696 xfrm_policy_flush_secctx_check(u8 type, struct xfrm_audit *audit_info)
697 {
698 int dir, err = 0;
699
700 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
701 struct xfrm_policy *pol;
702 struct hlist_node *entry;
703 int i;
704
705 hlist_for_each_entry(pol, entry,
706 &xfrm_policy_inexact[dir], bydst) {
707 if (pol->type != type)
708 continue;
709 err = security_xfrm_policy_delete(pol);
710 if (err) {
711 xfrm_audit_policy_delete(pol, 0,
712 audit_info->loginuid,
713 audit_info->secid);
714 return err;
715 }
716 }
717 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
718 hlist_for_each_entry(pol, entry,
719 xfrm_policy_bydst[dir].table + i,
720 bydst) {
721 if (pol->type != type)
722 continue;
723 err = security_xfrm_policy_delete(pol);
724 if (err) {
725 xfrm_audit_policy_delete(pol, 0,
726 audit_info->loginuid,
727 audit_info->secid);
728 return err;
729 }
730 }
731 }
732 }
733 return err;
734 }
735 #else
736 static inline int
737 xfrm_policy_flush_secctx_check(u8 type, struct xfrm_audit *audit_info)
738 {
739 return 0;
740 }
741 #endif
742
743 int xfrm_policy_flush(u8 type, struct xfrm_audit *audit_info)
744 {
745 int dir, err = 0;
746
747 write_lock_bh(&xfrm_policy_lock);
748
749 err = xfrm_policy_flush_secctx_check(type, audit_info);
750 if (err)
751 goto out;
752
753 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
754 struct xfrm_policy *pol;
755 struct hlist_node *entry;
756 int i, killed;
757
758 killed = 0;
759 again1:
760 hlist_for_each_entry(pol, entry,
761 &xfrm_policy_inexact[dir], bydst) {
762 if (pol->type != type)
763 continue;
764 hlist_del(&pol->bydst);
765 hlist_del(&pol->byidx);
766 write_unlock_bh(&xfrm_policy_lock);
767
768 xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
769 audit_info->secid);
770
771 xfrm_policy_kill(pol);
772 killed++;
773
774 write_lock_bh(&xfrm_policy_lock);
775 goto again1;
776 }
777
778 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
779 again2:
780 hlist_for_each_entry(pol, entry,
781 xfrm_policy_bydst[dir].table + i,
782 bydst) {
783 if (pol->type != type)
784 continue;
785 hlist_del(&pol->bydst);
786 hlist_del(&pol->byidx);
787 write_unlock_bh(&xfrm_policy_lock);
788
789 xfrm_audit_policy_delete(pol, 1,
790 audit_info->loginuid,
791 audit_info->secid);
792 xfrm_policy_kill(pol);
793 killed++;
794
795 write_lock_bh(&xfrm_policy_lock);
796 goto again2;
797 }
798 }
799
800 xfrm_policy_count[dir] -= killed;
801 }
802 atomic_inc(&flow_cache_genid);
803 out:
804 write_unlock_bh(&xfrm_policy_lock);
805 return err;
806 }
807 EXPORT_SYMBOL(xfrm_policy_flush);
808
809 int xfrm_policy_walk(u8 type, int (*func)(struct xfrm_policy *, int, int, void*),
810 void *data)
811 {
812 struct xfrm_policy *pol, *last = NULL;
813 struct hlist_node *entry;
814 int dir, last_dir = 0, count, error;
815
816 read_lock_bh(&xfrm_policy_lock);
817 count = 0;
818
819 for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
820 struct hlist_head *table = xfrm_policy_bydst[dir].table;
821 int i;
822
823 hlist_for_each_entry(pol, entry,
824 &xfrm_policy_inexact[dir], bydst) {
825 if (pol->type != type)
826 continue;
827 if (last) {
828 error = func(last, last_dir % XFRM_POLICY_MAX,
829 count, data);
830 if (error)
831 goto out;
832 }
833 last = pol;
834 last_dir = dir;
835 count++;
836 }
837 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
838 hlist_for_each_entry(pol, entry, table + i, bydst) {
839 if (pol->type != type)
840 continue;
841 if (last) {
842 error = func(last, last_dir % XFRM_POLICY_MAX,
843 count, data);
844 if (error)
845 goto out;
846 }
847 last = pol;
848 last_dir = dir;
849 count++;
850 }
851 }
852 }
853 if (count == 0) {
854 error = -ENOENT;
855 goto out;
856 }
857 error = func(last, last_dir % XFRM_POLICY_MAX, 0, data);
858 out:
859 read_unlock_bh(&xfrm_policy_lock);
860 return error;
861 }
862 EXPORT_SYMBOL(xfrm_policy_walk);
863
864 /*
865 * Find policy to apply to this flow.
866 *
867 * Returns 0 if policy found, else an -errno.
868 */
869 static int xfrm_policy_match(struct xfrm_policy *pol, struct flowi *fl,
870 u8 type, u16 family, int dir)
871 {
872 struct xfrm_selector *sel = &pol->selector;
873 int match, ret = -ESRCH;
874
875 if (pol->family != family ||
876 pol->type != type)
877 return ret;
878
879 match = xfrm_selector_match(sel, fl, family);
880 if (match)
881 ret = security_xfrm_policy_lookup(pol, fl->secid, dir);
882
883 return ret;
884 }
885
886 static struct xfrm_policy *xfrm_policy_lookup_bytype(u8 type, struct flowi *fl,
887 u16 family, u8 dir)
888 {
889 int err;
890 struct xfrm_policy *pol, *ret;
891 xfrm_address_t *daddr, *saddr;
892 struct hlist_node *entry;
893 struct hlist_head *chain;
894 u32 priority = ~0U;
895
896 daddr = xfrm_flowi_daddr(fl, family);
897 saddr = xfrm_flowi_saddr(fl, family);
898 if (unlikely(!daddr || !saddr))
899 return NULL;
900
901 read_lock_bh(&xfrm_policy_lock);
902 chain = policy_hash_direct(daddr, saddr, family, dir);
903 ret = NULL;
904 hlist_for_each_entry(pol, entry, chain, bydst) {
905 err = xfrm_policy_match(pol, fl, type, family, dir);
906 if (err) {
907 if (err == -ESRCH)
908 continue;
909 else {
910 ret = ERR_PTR(err);
911 goto fail;
912 }
913 } else {
914 ret = pol;
915 priority = ret->priority;
916 break;
917 }
918 }
919 chain = &xfrm_policy_inexact[dir];
920 hlist_for_each_entry(pol, entry, chain, bydst) {
921 err = xfrm_policy_match(pol, fl, type, family, dir);
922 if (err) {
923 if (err == -ESRCH)
924 continue;
925 else {
926 ret = ERR_PTR(err);
927 goto fail;
928 }
929 } else if (pol->priority < priority) {
930 ret = pol;
931 break;
932 }
933 }
934 if (ret)
935 xfrm_pol_hold(ret);
936 fail:
937 read_unlock_bh(&xfrm_policy_lock);
938
939 return ret;
940 }
941
942 static int xfrm_policy_lookup(struct flowi *fl, u16 family, u8 dir,
943 void **objp, atomic_t **obj_refp)
944 {
945 struct xfrm_policy *pol;
946 int err = 0;
947
948 #ifdef CONFIG_XFRM_SUB_POLICY
949 pol = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_SUB, fl, family, dir);
950 if (IS_ERR(pol)) {
951 err = PTR_ERR(pol);
952 pol = NULL;
953 }
954 if (pol || err)
955 goto end;
956 #endif
957 pol = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN, fl, family, dir);
958 if (IS_ERR(pol)) {
959 err = PTR_ERR(pol);
960 pol = NULL;
961 }
962 #ifdef CONFIG_XFRM_SUB_POLICY
963 end:
964 #endif
965 if ((*objp = (void *) pol) != NULL)
966 *obj_refp = &pol->refcnt;
967 return err;
968 }
969
970 static inline int policy_to_flow_dir(int dir)
971 {
972 if (XFRM_POLICY_IN == FLOW_DIR_IN &&
973 XFRM_POLICY_OUT == FLOW_DIR_OUT &&
974 XFRM_POLICY_FWD == FLOW_DIR_FWD)
975 return dir;
976 switch (dir) {
977 default:
978 case XFRM_POLICY_IN:
979 return FLOW_DIR_IN;
980 case XFRM_POLICY_OUT:
981 return FLOW_DIR_OUT;
982 case XFRM_POLICY_FWD:
983 return FLOW_DIR_FWD;
984 }
985 }
986
987 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
988 {
989 struct xfrm_policy *pol;
990
991 read_lock_bh(&xfrm_policy_lock);
992 if ((pol = sk->sk_policy[dir]) != NULL) {
993 int match = xfrm_selector_match(&pol->selector, fl,
994 sk->sk_family);
995 int err = 0;
996
997 if (match) {
998 err = security_xfrm_policy_lookup(pol, fl->secid,
999 policy_to_flow_dir(dir));
1000 if (!err)
1001 xfrm_pol_hold(pol);
1002 else if (err == -ESRCH)
1003 pol = NULL;
1004 else
1005 pol = ERR_PTR(err);
1006 } else
1007 pol = NULL;
1008 }
1009 read_unlock_bh(&xfrm_policy_lock);
1010 return pol;
1011 }
1012
1013 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1014 {
1015 struct hlist_head *chain = policy_hash_bysel(&pol->selector,
1016 pol->family, dir);
1017
1018 hlist_add_head(&pol->bydst, chain);
1019 hlist_add_head(&pol->byidx, xfrm_policy_byidx+idx_hash(pol->index));
1020 xfrm_policy_count[dir]++;
1021 xfrm_pol_hold(pol);
1022
1023 if (xfrm_bydst_should_resize(dir, NULL))
1024 schedule_work(&xfrm_hash_work);
1025 }
1026
1027 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1028 int dir)
1029 {
1030 if (hlist_unhashed(&pol->bydst))
1031 return NULL;
1032
1033 hlist_del(&pol->bydst);
1034 hlist_del(&pol->byidx);
1035 xfrm_policy_count[dir]--;
1036
1037 return pol;
1038 }
1039
1040 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1041 {
1042 write_lock_bh(&xfrm_policy_lock);
1043 pol = __xfrm_policy_unlink(pol, dir);
1044 write_unlock_bh(&xfrm_policy_lock);
1045 if (pol) {
1046 if (dir < XFRM_POLICY_MAX)
1047 atomic_inc(&flow_cache_genid);
1048 xfrm_policy_kill(pol);
1049 return 0;
1050 }
1051 return -ENOENT;
1052 }
1053 EXPORT_SYMBOL(xfrm_policy_delete);
1054
1055 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1056 {
1057 struct xfrm_policy *old_pol;
1058
1059 #ifdef CONFIG_XFRM_SUB_POLICY
1060 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1061 return -EINVAL;
1062 #endif
1063
1064 write_lock_bh(&xfrm_policy_lock);
1065 old_pol = sk->sk_policy[dir];
1066 sk->sk_policy[dir] = pol;
1067 if (pol) {
1068 pol->curlft.add_time = get_seconds();
1069 pol->index = xfrm_gen_index(pol->type, XFRM_POLICY_MAX+dir);
1070 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1071 }
1072 if (old_pol)
1073 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1074 write_unlock_bh(&xfrm_policy_lock);
1075
1076 if (old_pol) {
1077 xfrm_policy_kill(old_pol);
1078 }
1079 return 0;
1080 }
1081
1082 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
1083 {
1084 struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC);
1085
1086 if (newp) {
1087 newp->selector = old->selector;
1088 if (security_xfrm_policy_clone(old, newp)) {
1089 kfree(newp);
1090 return NULL; /* ENOMEM */
1091 }
1092 newp->lft = old->lft;
1093 newp->curlft = old->curlft;
1094 newp->action = old->action;
1095 newp->flags = old->flags;
1096 newp->xfrm_nr = old->xfrm_nr;
1097 newp->index = old->index;
1098 newp->type = old->type;
1099 memcpy(newp->xfrm_vec, old->xfrm_vec,
1100 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1101 write_lock_bh(&xfrm_policy_lock);
1102 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1103 write_unlock_bh(&xfrm_policy_lock);
1104 xfrm_pol_put(newp);
1105 }
1106 return newp;
1107 }
1108
1109 int __xfrm_sk_clone_policy(struct sock *sk)
1110 {
1111 struct xfrm_policy *p0 = sk->sk_policy[0],
1112 *p1 = sk->sk_policy[1];
1113
1114 sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1115 if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1116 return -ENOMEM;
1117 if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1118 return -ENOMEM;
1119 return 0;
1120 }
1121
1122 static int
1123 xfrm_get_saddr(xfrm_address_t *local, xfrm_address_t *remote,
1124 unsigned short family)
1125 {
1126 int err;
1127 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1128
1129 if (unlikely(afinfo == NULL))
1130 return -EINVAL;
1131 err = afinfo->get_saddr(local, remote);
1132 xfrm_policy_put_afinfo(afinfo);
1133 return err;
1134 }
1135
1136 /* Resolve list of templates for the flow, given policy. */
1137
1138 static int
1139 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, struct flowi *fl,
1140 struct xfrm_state **xfrm,
1141 unsigned short family)
1142 {
1143 int nx;
1144 int i, error;
1145 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1146 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1147 xfrm_address_t tmp;
1148
1149 for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1150 struct xfrm_state *x;
1151 xfrm_address_t *remote = daddr;
1152 xfrm_address_t *local = saddr;
1153 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1154
1155 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1156 tmpl->mode == XFRM_MODE_BEET) {
1157 remote = &tmpl->id.daddr;
1158 local = &tmpl->saddr;
1159 family = tmpl->encap_family;
1160 if (xfrm_addr_any(local, family)) {
1161 error = xfrm_get_saddr(&tmp, remote, family);
1162 if (error)
1163 goto fail;
1164 local = &tmp;
1165 }
1166 }
1167
1168 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1169
1170 if (x && x->km.state == XFRM_STATE_VALID) {
1171 xfrm[nx++] = x;
1172 daddr = remote;
1173 saddr = local;
1174 continue;
1175 }
1176 if (x) {
1177 error = (x->km.state == XFRM_STATE_ERROR ?
1178 -EINVAL : -EAGAIN);
1179 xfrm_state_put(x);
1180 }
1181
1182 if (!tmpl->optional)
1183 goto fail;
1184 }
1185 return nx;
1186
1187 fail:
1188 for (nx--; nx>=0; nx--)
1189 xfrm_state_put(xfrm[nx]);
1190 return error;
1191 }
1192
1193 static int
1194 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
1195 struct xfrm_state **xfrm,
1196 unsigned short family)
1197 {
1198 struct xfrm_state *tp[XFRM_MAX_DEPTH];
1199 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1200 int cnx = 0;
1201 int error;
1202 int ret;
1203 int i;
1204
1205 for (i = 0; i < npols; i++) {
1206 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1207 error = -ENOBUFS;
1208 goto fail;
1209 }
1210
1211 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1212 if (ret < 0) {
1213 error = ret;
1214 goto fail;
1215 } else
1216 cnx += ret;
1217 }
1218
1219 /* found states are sorted for outbound processing */
1220 if (npols > 1)
1221 xfrm_state_sort(xfrm, tpp, cnx, family);
1222
1223 return cnx;
1224
1225 fail:
1226 for (cnx--; cnx>=0; cnx--)
1227 xfrm_state_put(tpp[cnx]);
1228 return error;
1229
1230 }
1231
1232 /* Check that the bundle accepts the flow and its components are
1233 * still valid.
1234 */
1235
1236 static struct dst_entry *
1237 xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family)
1238 {
1239 struct dst_entry *x;
1240 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1241 if (unlikely(afinfo == NULL))
1242 return ERR_PTR(-EINVAL);
1243 x = afinfo->find_bundle(fl, policy);
1244 xfrm_policy_put_afinfo(afinfo);
1245 return x;
1246 }
1247
1248 static inline int xfrm_get_tos(struct flowi *fl, int family)
1249 {
1250 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1251 int tos;
1252
1253 if (!afinfo)
1254 return -EINVAL;
1255
1256 tos = afinfo->get_tos(fl);
1257
1258 xfrm_policy_put_afinfo(afinfo);
1259
1260 return tos;
1261 }
1262
1263 static inline struct xfrm_dst *xfrm_alloc_dst(int family)
1264 {
1265 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1266 struct xfrm_dst *xdst;
1267
1268 if (!afinfo)
1269 return ERR_PTR(-EINVAL);
1270
1271 xdst = dst_alloc(afinfo->dst_ops) ?: ERR_PTR(-ENOBUFS);
1272
1273 xfrm_policy_put_afinfo(afinfo);
1274
1275 return xdst;
1276 }
1277
1278 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1279 int nfheader_len)
1280 {
1281 struct xfrm_policy_afinfo *afinfo =
1282 xfrm_policy_get_afinfo(dst->ops->family);
1283 int err;
1284
1285 if (!afinfo)
1286 return -EINVAL;
1287
1288 err = afinfo->init_path(path, dst, nfheader_len);
1289
1290 xfrm_policy_put_afinfo(afinfo);
1291
1292 return err;
1293 }
1294
1295 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev)
1296 {
1297 struct xfrm_policy_afinfo *afinfo =
1298 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1299 int err;
1300
1301 if (!afinfo)
1302 return -EINVAL;
1303
1304 err = afinfo->fill_dst(xdst, dev);
1305
1306 xfrm_policy_put_afinfo(afinfo);
1307
1308 return err;
1309 }
1310
1311 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1312 * all the metrics... Shortly, bundle a bundle.
1313 */
1314
1315 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1316 struct xfrm_state **xfrm, int nx,
1317 struct flowi *fl,
1318 struct dst_entry *dst)
1319 {
1320 unsigned long now = jiffies;
1321 struct net_device *dev;
1322 struct dst_entry *dst_prev = NULL;
1323 struct dst_entry *dst0 = NULL;
1324 int i = 0;
1325 int err;
1326 int header_len = 0;
1327 int nfheader_len = 0;
1328 int trailer_len = 0;
1329 int tos;
1330 int family = policy->selector.family;
1331
1332 tos = xfrm_get_tos(fl, family);
1333 err = tos;
1334 if (tos < 0)
1335 goto put_states;
1336
1337 dst_hold(dst);
1338
1339 for (; i < nx; i++) {
1340 struct xfrm_dst *xdst = xfrm_alloc_dst(family);
1341 struct dst_entry *dst1 = &xdst->u.dst;
1342
1343 err = PTR_ERR(xdst);
1344 if (IS_ERR(xdst)) {
1345 dst_release(dst);
1346 goto put_states;
1347 }
1348
1349 if (!dst_prev)
1350 dst0 = dst1;
1351 else {
1352 dst_prev->child = dst_clone(dst1);
1353 dst1->flags |= DST_NOHASH;
1354 }
1355
1356 xdst->route = dst;
1357 memcpy(&dst1->metrics, &dst->metrics, sizeof(dst->metrics));
1358
1359 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1360 family = xfrm[i]->props.family;
1361 dst = xfrm_dst_lookup(xfrm[i], tos, family);
1362 err = PTR_ERR(dst);
1363 if (IS_ERR(dst))
1364 goto put_states;
1365 } else
1366 dst_hold(dst);
1367
1368 dst1->xfrm = xfrm[i];
1369 xdst->genid = xfrm[i]->genid;
1370
1371 dst1->obsolete = -1;
1372 dst1->flags |= DST_HOST;
1373 dst1->lastuse = now;
1374
1375 dst1->input = dst_discard;
1376 dst1->output = xfrm[i]->outer_mode->afinfo->output;
1377
1378 dst1->next = dst_prev;
1379 dst_prev = dst1;
1380
1381 header_len += xfrm[i]->props.header_len;
1382 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1383 nfheader_len += xfrm[i]->props.header_len;
1384 trailer_len += xfrm[i]->props.trailer_len;
1385 }
1386
1387 dst_prev->child = dst;
1388 dst0->path = dst;
1389
1390 err = -ENODEV;
1391 dev = dst->dev;
1392 if (!dev)
1393 goto free_dst;
1394
1395 /* Copy neighbout for reachability confirmation */
1396 dst0->neighbour = neigh_clone(dst->neighbour);
1397
1398 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1399 xfrm_init_pmtu(dst_prev);
1400
1401 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1402 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1403
1404 err = xfrm_fill_dst(xdst, dev);
1405 if (err)
1406 goto free_dst;
1407
1408 dst_prev->header_len = header_len;
1409 dst_prev->trailer_len = trailer_len;
1410 header_len -= xdst->u.dst.xfrm->props.header_len;
1411 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1412 }
1413
1414 out:
1415 return dst0;
1416
1417 put_states:
1418 for (; i < nx; i++)
1419 xfrm_state_put(xfrm[i]);
1420 free_dst:
1421 if (dst0)
1422 dst_free(dst0);
1423 dst0 = ERR_PTR(err);
1424 goto out;
1425 }
1426
1427 static int inline
1428 xfrm_dst_alloc_copy(void **target, void *src, int size)
1429 {
1430 if (!*target) {
1431 *target = kmalloc(size, GFP_ATOMIC);
1432 if (!*target)
1433 return -ENOMEM;
1434 }
1435 memcpy(*target, src, size);
1436 return 0;
1437 }
1438
1439 static int inline
1440 xfrm_dst_update_parent(struct dst_entry *dst, struct xfrm_selector *sel)
1441 {
1442 #ifdef CONFIG_XFRM_SUB_POLICY
1443 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1444 return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1445 sel, sizeof(*sel));
1446 #else
1447 return 0;
1448 #endif
1449 }
1450
1451 static int inline
1452 xfrm_dst_update_origin(struct dst_entry *dst, struct flowi *fl)
1453 {
1454 #ifdef CONFIG_XFRM_SUB_POLICY
1455 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1456 return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1457 #else
1458 return 0;
1459 #endif
1460 }
1461
1462 static int stale_bundle(struct dst_entry *dst);
1463
1464 /* Main function: finds/creates a bundle for given flow.
1465 *
1466 * At the moment we eat a raw IP route. Mostly to speed up lookups
1467 * on interfaces with disabled IPsec.
1468 */
1469 int __xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl,
1470 struct sock *sk, int flags)
1471 {
1472 struct xfrm_policy *policy;
1473 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1474 int npols;
1475 int pol_dead;
1476 int xfrm_nr;
1477 int pi;
1478 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1479 struct dst_entry *dst, *dst_orig = *dst_p;
1480 int nx = 0;
1481 int err;
1482 u32 genid;
1483 u16 family;
1484 u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
1485
1486 restart:
1487 genid = atomic_read(&flow_cache_genid);
1488 policy = NULL;
1489 for (pi = 0; pi < ARRAY_SIZE(pols); pi++)
1490 pols[pi] = NULL;
1491 npols = 0;
1492 pol_dead = 0;
1493 xfrm_nr = 0;
1494
1495 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
1496 policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
1497 err = PTR_ERR(policy);
1498 if (IS_ERR(policy)) {
1499 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLERROR);
1500 goto dropdst;
1501 }
1502 }
1503
1504 if (!policy) {
1505 /* To accelerate a bit... */
1506 if ((dst_orig->flags & DST_NOXFRM) ||
1507 !xfrm_policy_count[XFRM_POLICY_OUT])
1508 goto nopol;
1509
1510 policy = flow_cache_lookup(fl, dst_orig->ops->family,
1511 dir, xfrm_policy_lookup);
1512 err = PTR_ERR(policy);
1513 if (IS_ERR(policy))
1514 goto dropdst;
1515 }
1516
1517 if (!policy)
1518 goto nopol;
1519
1520 family = dst_orig->ops->family;
1521 pols[0] = policy;
1522 npols ++;
1523 xfrm_nr += pols[0]->xfrm_nr;
1524
1525 err = -ENOENT;
1526 if ((flags & XFRM_LOOKUP_ICMP) && !(policy->flags & XFRM_POLICY_ICMP))
1527 goto error;
1528
1529 policy->curlft.use_time = get_seconds();
1530
1531 switch (policy->action) {
1532 default:
1533 case XFRM_POLICY_BLOCK:
1534 /* Prohibit the flow */
1535 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLBLOCK);
1536 err = -EPERM;
1537 goto error;
1538
1539 case XFRM_POLICY_ALLOW:
1540 #ifndef CONFIG_XFRM_SUB_POLICY
1541 if (policy->xfrm_nr == 0) {
1542 /* Flow passes not transformed. */
1543 xfrm_pol_put(policy);
1544 return 0;
1545 }
1546 #endif
1547
1548 /* Try to find matching bundle.
1549 *
1550 * LATER: help from flow cache. It is optional, this
1551 * is required only for output policy.
1552 */
1553 dst = xfrm_find_bundle(fl, policy, family);
1554 if (IS_ERR(dst)) {
1555 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1556 err = PTR_ERR(dst);
1557 goto error;
1558 }
1559
1560 if (dst)
1561 break;
1562
1563 #ifdef CONFIG_XFRM_SUB_POLICY
1564 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1565 pols[1] = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN,
1566 fl, family,
1567 XFRM_POLICY_OUT);
1568 if (pols[1]) {
1569 if (IS_ERR(pols[1])) {
1570 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLERROR);
1571 err = PTR_ERR(pols[1]);
1572 goto error;
1573 }
1574 if (pols[1]->action == XFRM_POLICY_BLOCK) {
1575 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLBLOCK);
1576 err = -EPERM;
1577 goto error;
1578 }
1579 npols ++;
1580 xfrm_nr += pols[1]->xfrm_nr;
1581 }
1582 }
1583
1584 /*
1585 * Because neither flowi nor bundle information knows about
1586 * transformation template size. On more than one policy usage
1587 * we can realize whether all of them is bypass or not after
1588 * they are searched. See above not-transformed bypass
1589 * is surrounded by non-sub policy configuration, too.
1590 */
1591 if (xfrm_nr == 0) {
1592 /* Flow passes not transformed. */
1593 xfrm_pols_put(pols, npols);
1594 return 0;
1595 }
1596
1597 #endif
1598 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1599
1600 if (unlikely(nx<0)) {
1601 err = nx;
1602 if (err == -EAGAIN && sysctl_xfrm_larval_drop) {
1603 /* EREMOTE tells the caller to generate
1604 * a one-shot blackhole route.
1605 */
1606 xfrm_pol_put(policy);
1607 return -EREMOTE;
1608 }
1609 if (err == -EAGAIN && (flags & XFRM_LOOKUP_WAIT)) {
1610 DECLARE_WAITQUEUE(wait, current);
1611
1612 add_wait_queue(&km_waitq, &wait);
1613 set_current_state(TASK_INTERRUPTIBLE);
1614 schedule();
1615 set_current_state(TASK_RUNNING);
1616 remove_wait_queue(&km_waitq, &wait);
1617
1618 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1619
1620 if (nx == -EAGAIN && signal_pending(current)) {
1621 XFRM_INC_STATS(LINUX_MIB_XFRMOUTNOSTATES);
1622 err = -ERESTART;
1623 goto error;
1624 }
1625 if (nx == -EAGAIN ||
1626 genid != atomic_read(&flow_cache_genid)) {
1627 xfrm_pols_put(pols, npols);
1628 goto restart;
1629 }
1630 err = nx;
1631 }
1632 if (err < 0) {
1633 XFRM_INC_STATS(LINUX_MIB_XFRMOUTNOSTATES);
1634 goto error;
1635 }
1636 }
1637 if (nx == 0) {
1638 /* Flow passes not transformed. */
1639 xfrm_pols_put(pols, npols);
1640 return 0;
1641 }
1642
1643 dst = xfrm_bundle_create(policy, xfrm, nx, fl, dst_orig);
1644 err = PTR_ERR(dst);
1645 if (IS_ERR(dst)) {
1646 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1647 goto error;
1648 }
1649
1650 for (pi = 0; pi < npols; pi++) {
1651 read_lock_bh(&pols[pi]->lock);
1652 pol_dead |= pols[pi]->dead;
1653 read_unlock_bh(&pols[pi]->lock);
1654 }
1655
1656 write_lock_bh(&policy->lock);
1657 if (unlikely(pol_dead || stale_bundle(dst))) {
1658 /* Wow! While we worked on resolving, this
1659 * policy has gone. Retry. It is not paranoia,
1660 * we just cannot enlist new bundle to dead object.
1661 * We can't enlist stable bundles either.
1662 */
1663 write_unlock_bh(&policy->lock);
1664 if (dst)
1665 dst_free(dst);
1666
1667 if (pol_dead)
1668 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLDEAD);
1669 else
1670 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1671 err = -EHOSTUNREACH;
1672 goto error;
1673 }
1674
1675 if (npols > 1)
1676 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1677 else
1678 err = xfrm_dst_update_origin(dst, fl);
1679 if (unlikely(err)) {
1680 write_unlock_bh(&policy->lock);
1681 if (dst)
1682 dst_free(dst);
1683 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1684 goto error;
1685 }
1686
1687 dst->next = policy->bundles;
1688 policy->bundles = dst;
1689 dst_hold(dst);
1690 write_unlock_bh(&policy->lock);
1691 }
1692 *dst_p = dst;
1693 dst_release(dst_orig);
1694 xfrm_pols_put(pols, npols);
1695 return 0;
1696
1697 error:
1698 xfrm_pols_put(pols, npols);
1699 dropdst:
1700 dst_release(dst_orig);
1701 *dst_p = NULL;
1702 return err;
1703
1704 nopol:
1705 err = -ENOENT;
1706 if (flags & XFRM_LOOKUP_ICMP)
1707 goto dropdst;
1708 return 0;
1709 }
1710 EXPORT_SYMBOL(__xfrm_lookup);
1711
1712 int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl,
1713 struct sock *sk, int flags)
1714 {
1715 int err = __xfrm_lookup(dst_p, fl, sk, flags);
1716
1717 if (err == -EREMOTE) {
1718 dst_release(*dst_p);
1719 *dst_p = NULL;
1720 err = -EAGAIN;
1721 }
1722
1723 return err;
1724 }
1725 EXPORT_SYMBOL(xfrm_lookup);
1726
1727 static inline int
1728 xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
1729 {
1730 struct xfrm_state *x;
1731
1732 if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1733 return 0;
1734 x = skb->sp->xvec[idx];
1735 if (!x->type->reject)
1736 return 0;
1737 return x->type->reject(x, skb, fl);
1738 }
1739
1740 /* When skb is transformed back to its "native" form, we have to
1741 * check policy restrictions. At the moment we make this in maximally
1742 * stupid way. Shame on me. :-) Of course, connected sockets must
1743 * have policy cached at them.
1744 */
1745
1746 static inline int
1747 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
1748 unsigned short family)
1749 {
1750 if (xfrm_state_kern(x))
1751 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
1752 return x->id.proto == tmpl->id.proto &&
1753 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1754 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1755 x->props.mode == tmpl->mode &&
1756 ((tmpl->aalgos & (1<<x->props.aalgo)) ||
1757 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1758 !(x->props.mode != XFRM_MODE_TRANSPORT &&
1759 xfrm_state_addr_cmp(tmpl, x, family));
1760 }
1761
1762 /*
1763 * 0 or more than 0 is returned when validation is succeeded (either bypass
1764 * because of optional transport mode, or next index of the mathced secpath
1765 * state with the template.
1766 * -1 is returned when no matching template is found.
1767 * Otherwise "-2 - errored_index" is returned.
1768 */
1769 static inline int
1770 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1771 unsigned short family)
1772 {
1773 int idx = start;
1774
1775 if (tmpl->optional) {
1776 if (tmpl->mode == XFRM_MODE_TRANSPORT)
1777 return start;
1778 } else
1779 start = -1;
1780 for (; idx < sp->len; idx++) {
1781 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1782 return ++idx;
1783 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
1784 if (start == -1)
1785 start = -2-idx;
1786 break;
1787 }
1788 }
1789 return start;
1790 }
1791
1792 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1793 unsigned int family, int reverse)
1794 {
1795 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1796 int err;
1797
1798 if (unlikely(afinfo == NULL))
1799 return -EAFNOSUPPORT;
1800
1801 afinfo->decode_session(skb, fl, reverse);
1802 err = security_xfrm_decode_session(skb, &fl->secid);
1803 xfrm_policy_put_afinfo(afinfo);
1804 return err;
1805 }
1806 EXPORT_SYMBOL(__xfrm_decode_session);
1807
1808 static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
1809 {
1810 for (; k < sp->len; k++) {
1811 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
1812 *idxp = k;
1813 return 1;
1814 }
1815 }
1816
1817 return 0;
1818 }
1819
1820 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
1821 unsigned short family)
1822 {
1823 struct xfrm_policy *pol;
1824 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1825 int npols = 0;
1826 int xfrm_nr;
1827 int pi;
1828 int reverse;
1829 struct flowi fl;
1830 u8 fl_dir;
1831 int xerr_idx = -1;
1832
1833 reverse = dir & ~XFRM_POLICY_MASK;
1834 dir &= XFRM_POLICY_MASK;
1835 fl_dir = policy_to_flow_dir(dir);
1836
1837 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
1838 XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR);
1839 return 0;
1840 }
1841
1842 nf_nat_decode_session(skb, &fl, family);
1843
1844 /* First, check used SA against their selectors. */
1845 if (skb->sp) {
1846 int i;
1847
1848 for (i=skb->sp->len-1; i>=0; i--) {
1849 struct xfrm_state *x = skb->sp->xvec[i];
1850 if (!xfrm_selector_match(&x->sel, &fl, family)) {
1851 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEMISMATCH);
1852 return 0;
1853 }
1854 }
1855 }
1856
1857 pol = NULL;
1858 if (sk && sk->sk_policy[dir]) {
1859 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
1860 if (IS_ERR(pol)) {
1861 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLERROR);
1862 return 0;
1863 }
1864 }
1865
1866 if (!pol)
1867 pol = flow_cache_lookup(&fl, family, fl_dir,
1868 xfrm_policy_lookup);
1869
1870 if (IS_ERR(pol)) {
1871 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLERROR);
1872 return 0;
1873 }
1874
1875 if (!pol) {
1876 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
1877 xfrm_secpath_reject(xerr_idx, skb, &fl);
1878 XFRM_INC_STATS(LINUX_MIB_XFRMINNOPOLS);
1879 return 0;
1880 }
1881 return 1;
1882 }
1883
1884 pol->curlft.use_time = get_seconds();
1885
1886 pols[0] = pol;
1887 npols ++;
1888 #ifdef CONFIG_XFRM_SUB_POLICY
1889 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1890 pols[1] = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN,
1891 &fl, family,
1892 XFRM_POLICY_IN);
1893 if (pols[1]) {
1894 if (IS_ERR(pols[1])) {
1895 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLERROR);
1896 return 0;
1897 }
1898 pols[1]->curlft.use_time = get_seconds();
1899 npols ++;
1900 }
1901 }
1902 #endif
1903
1904 if (pol->action == XFRM_POLICY_ALLOW) {
1905 struct sec_path *sp;
1906 static struct sec_path dummy;
1907 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
1908 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
1909 struct xfrm_tmpl **tpp = tp;
1910 int ti = 0;
1911 int i, k;
1912
1913 if ((sp = skb->sp) == NULL)
1914 sp = &dummy;
1915
1916 for (pi = 0; pi < npols; pi++) {
1917 if (pols[pi] != pol &&
1918 pols[pi]->action != XFRM_POLICY_ALLOW) {
1919 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLBLOCK);
1920 goto reject;
1921 }
1922 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
1923 XFRM_INC_STATS(LINUX_MIB_XFRMINBUFFERERROR);
1924 goto reject_error;
1925 }
1926 for (i = 0; i < pols[pi]->xfrm_nr; i++)
1927 tpp[ti++] = &pols[pi]->xfrm_vec[i];
1928 }
1929 xfrm_nr = ti;
1930 if (npols > 1) {
1931 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
1932 tpp = stp;
1933 }
1934
1935 /* For each tunnel xfrm, find the first matching tmpl.
1936 * For each tmpl before that, find corresponding xfrm.
1937 * Order is _important_. Later we will implement
1938 * some barriers, but at the moment barriers
1939 * are implied between each two transformations.
1940 */
1941 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
1942 k = xfrm_policy_ok(tpp[i], sp, k, family);
1943 if (k < 0) {
1944 if (k < -1)
1945 /* "-2 - errored_index" returned */
1946 xerr_idx = -(2+k);
1947 XFRM_INC_STATS(LINUX_MIB_XFRMINTMPLMISMATCH);
1948 goto reject;
1949 }
1950 }
1951
1952 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
1953 XFRM_INC_STATS(LINUX_MIB_XFRMINTMPLMISMATCH);
1954 goto reject;
1955 }
1956
1957 xfrm_pols_put(pols, npols);
1958 return 1;
1959 }
1960 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLBLOCK);
1961
1962 reject:
1963 xfrm_secpath_reject(xerr_idx, skb, &fl);
1964 reject_error:
1965 xfrm_pols_put(pols, npols);
1966 return 0;
1967 }
1968 EXPORT_SYMBOL(__xfrm_policy_check);
1969
1970 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1971 {
1972 struct flowi fl;
1973
1974 if (xfrm_decode_session(skb, &fl, family) < 0) {
1975 /* XXX: we should have something like FWDHDRERROR here. */
1976 XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR);
1977 return 0;
1978 }
1979
1980 return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0;
1981 }
1982 EXPORT_SYMBOL(__xfrm_route_forward);
1983
1984 /* Optimize later using cookies and generation ids. */
1985
1986 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
1987 {
1988 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
1989 * to "-1" to force all XFRM destinations to get validated by
1990 * dst_ops->check on every use. We do this because when a
1991 * normal route referenced by an XFRM dst is obsoleted we do
1992 * not go looking around for all parent referencing XFRM dsts
1993 * so that we can invalidate them. It is just too much work.
1994 * Instead we make the checks here on every use. For example:
1995 *
1996 * XFRM dst A --> IPv4 dst X
1997 *
1998 * X is the "xdst->route" of A (X is also the "dst->path" of A
1999 * in this example). If X is marked obsolete, "A" will not
2000 * notice. That's what we are validating here via the
2001 * stale_bundle() check.
2002 *
2003 * When a policy's bundle is pruned, we dst_free() the XFRM
2004 * dst which causes it's ->obsolete field to be set to a
2005 * positive non-zero integer. If an XFRM dst has been pruned
2006 * like this, we want to force a new route lookup.
2007 */
2008 if (dst->obsolete < 0 && !stale_bundle(dst))
2009 return dst;
2010
2011 return NULL;
2012 }
2013
2014 static int stale_bundle(struct dst_entry *dst)
2015 {
2016 return !xfrm_bundle_ok(NULL, (struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
2017 }
2018
2019 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2020 {
2021 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2022 dst->dev = dev->nd_net->loopback_dev;
2023 dev_hold(dst->dev);
2024 dev_put(dev);
2025 }
2026 }
2027 EXPORT_SYMBOL(xfrm_dst_ifdown);
2028
2029 static void xfrm_link_failure(struct sk_buff *skb)
2030 {
2031 /* Impossible. Such dst must be popped before reaches point of failure. */
2032 return;
2033 }
2034
2035 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2036 {
2037 if (dst) {
2038 if (dst->obsolete) {
2039 dst_release(dst);
2040 dst = NULL;
2041 }
2042 }
2043 return dst;
2044 }
2045
2046 static void prune_one_bundle(struct xfrm_policy *pol, int (*func)(struct dst_entry *), struct dst_entry **gc_list_p)
2047 {
2048 struct dst_entry *dst, **dstp;
2049
2050 write_lock(&pol->lock);
2051 dstp = &pol->bundles;
2052 while ((dst=*dstp) != NULL) {
2053 if (func(dst)) {
2054 *dstp = dst->next;
2055 dst->next = *gc_list_p;
2056 *gc_list_p = dst;
2057 } else {
2058 dstp = &dst->next;
2059 }
2060 }
2061 write_unlock(&pol->lock);
2062 }
2063
2064 static void xfrm_prune_bundles(int (*func)(struct dst_entry *))
2065 {
2066 struct dst_entry *gc_list = NULL;
2067 int dir;
2068
2069 read_lock_bh(&xfrm_policy_lock);
2070 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2071 struct xfrm_policy *pol;
2072 struct hlist_node *entry;
2073 struct hlist_head *table;
2074 int i;
2075
2076 hlist_for_each_entry(pol, entry,
2077 &xfrm_policy_inexact[dir], bydst)
2078 prune_one_bundle(pol, func, &gc_list);
2079
2080 table = xfrm_policy_bydst[dir].table;
2081 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
2082 hlist_for_each_entry(pol, entry, table + i, bydst)
2083 prune_one_bundle(pol, func, &gc_list);
2084 }
2085 }
2086 read_unlock_bh(&xfrm_policy_lock);
2087
2088 while (gc_list) {
2089 struct dst_entry *dst = gc_list;
2090 gc_list = dst->next;
2091 dst_free(dst);
2092 }
2093 }
2094
2095 static int unused_bundle(struct dst_entry *dst)
2096 {
2097 return !atomic_read(&dst->__refcnt);
2098 }
2099
2100 static void __xfrm_garbage_collect(void)
2101 {
2102 xfrm_prune_bundles(unused_bundle);
2103 }
2104
2105 static int xfrm_flush_bundles(void)
2106 {
2107 xfrm_prune_bundles(stale_bundle);
2108 return 0;
2109 }
2110
2111 static void xfrm_init_pmtu(struct dst_entry *dst)
2112 {
2113 do {
2114 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2115 u32 pmtu, route_mtu_cached;
2116
2117 pmtu = dst_mtu(dst->child);
2118 xdst->child_mtu_cached = pmtu;
2119
2120 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2121
2122 route_mtu_cached = dst_mtu(xdst->route);
2123 xdst->route_mtu_cached = route_mtu_cached;
2124
2125 if (pmtu > route_mtu_cached)
2126 pmtu = route_mtu_cached;
2127
2128 dst->metrics[RTAX_MTU-1] = pmtu;
2129 } while ((dst = dst->next));
2130 }
2131
2132 /* Check that the bundle accepts the flow and its components are
2133 * still valid.
2134 */
2135
2136 int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
2137 struct flowi *fl, int family, int strict)
2138 {
2139 struct dst_entry *dst = &first->u.dst;
2140 struct xfrm_dst *last;
2141 u32 mtu;
2142
2143 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2144 (dst->dev && !netif_running(dst->dev)))
2145 return 0;
2146 #ifdef CONFIG_XFRM_SUB_POLICY
2147 if (fl) {
2148 if (first->origin && !flow_cache_uli_match(first->origin, fl))
2149 return 0;
2150 if (first->partner &&
2151 !xfrm_selector_match(first->partner, fl, family))
2152 return 0;
2153 }
2154 #endif
2155
2156 last = NULL;
2157
2158 do {
2159 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2160
2161 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
2162 return 0;
2163 if (fl && pol &&
2164 !security_xfrm_state_pol_flow_match(dst->xfrm, pol, fl))
2165 return 0;
2166 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2167 return 0;
2168 if (xdst->genid != dst->xfrm->genid)
2169 return 0;
2170
2171 if (strict && fl &&
2172 !(dst->xfrm->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
2173 !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
2174 return 0;
2175
2176 mtu = dst_mtu(dst->child);
2177 if (xdst->child_mtu_cached != mtu) {
2178 last = xdst;
2179 xdst->child_mtu_cached = mtu;
2180 }
2181
2182 if (!dst_check(xdst->route, xdst->route_cookie))
2183 return 0;
2184 mtu = dst_mtu(xdst->route);
2185 if (xdst->route_mtu_cached != mtu) {
2186 last = xdst;
2187 xdst->route_mtu_cached = mtu;
2188 }
2189
2190 dst = dst->child;
2191 } while (dst->xfrm);
2192
2193 if (likely(!last))
2194 return 1;
2195
2196 mtu = last->child_mtu_cached;
2197 for (;;) {
2198 dst = &last->u.dst;
2199
2200 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2201 if (mtu > last->route_mtu_cached)
2202 mtu = last->route_mtu_cached;
2203 dst->metrics[RTAX_MTU-1] = mtu;
2204
2205 if (last == first)
2206 break;
2207
2208 last = (struct xfrm_dst *)last->u.dst.next;
2209 last->child_mtu_cached = mtu;
2210 }
2211
2212 return 1;
2213 }
2214
2215 EXPORT_SYMBOL(xfrm_bundle_ok);
2216
2217 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2218 {
2219 int err = 0;
2220 if (unlikely(afinfo == NULL))
2221 return -EINVAL;
2222 if (unlikely(afinfo->family >= NPROTO))
2223 return -EAFNOSUPPORT;
2224 write_lock_bh(&xfrm_policy_afinfo_lock);
2225 if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2226 err = -ENOBUFS;
2227 else {
2228 struct dst_ops *dst_ops = afinfo->dst_ops;
2229 if (likely(dst_ops->kmem_cachep == NULL))
2230 dst_ops->kmem_cachep = xfrm_dst_cache;
2231 if (likely(dst_ops->check == NULL))
2232 dst_ops->check = xfrm_dst_check;
2233 if (likely(dst_ops->negative_advice == NULL))
2234 dst_ops->negative_advice = xfrm_negative_advice;
2235 if (likely(dst_ops->link_failure == NULL))
2236 dst_ops->link_failure = xfrm_link_failure;
2237 if (likely(afinfo->garbage_collect == NULL))
2238 afinfo->garbage_collect = __xfrm_garbage_collect;
2239 xfrm_policy_afinfo[afinfo->family] = afinfo;
2240 }
2241 write_unlock_bh(&xfrm_policy_afinfo_lock);
2242 return err;
2243 }
2244 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2245
2246 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2247 {
2248 int err = 0;
2249 if (unlikely(afinfo == NULL))
2250 return -EINVAL;
2251 if (unlikely(afinfo->family >= NPROTO))
2252 return -EAFNOSUPPORT;
2253 write_lock_bh(&xfrm_policy_afinfo_lock);
2254 if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2255 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2256 err = -EINVAL;
2257 else {
2258 struct dst_ops *dst_ops = afinfo->dst_ops;
2259 xfrm_policy_afinfo[afinfo->family] = NULL;
2260 dst_ops->kmem_cachep = NULL;
2261 dst_ops->check = NULL;
2262 dst_ops->negative_advice = NULL;
2263 dst_ops->link_failure = NULL;
2264 afinfo->garbage_collect = NULL;
2265 }
2266 }
2267 write_unlock_bh(&xfrm_policy_afinfo_lock);
2268 return err;
2269 }
2270 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2271
2272 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
2273 {
2274 struct xfrm_policy_afinfo *afinfo;
2275 if (unlikely(family >= NPROTO))
2276 return NULL;
2277 read_lock(&xfrm_policy_afinfo_lock);
2278 afinfo = xfrm_policy_afinfo[family];
2279 if (unlikely(!afinfo))
2280 read_unlock(&xfrm_policy_afinfo_lock);
2281 return afinfo;
2282 }
2283
2284 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
2285 {
2286 read_unlock(&xfrm_policy_afinfo_lock);
2287 }
2288
2289 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2290 {
2291 struct net_device *dev = ptr;
2292
2293 if (dev->nd_net != &init_net)
2294 return NOTIFY_DONE;
2295
2296 switch (event) {
2297 case NETDEV_DOWN:
2298 xfrm_flush_bundles();
2299 }
2300 return NOTIFY_DONE;
2301 }
2302
2303 static struct notifier_block xfrm_dev_notifier = {
2304 xfrm_dev_event,
2305 NULL,
2306 0
2307 };
2308
2309 #ifdef CONFIG_XFRM_STATISTICS
2310 static int __init xfrm_statistics_init(void)
2311 {
2312 if (snmp_mib_init((void **)xfrm_statistics,
2313 sizeof(struct linux_xfrm_mib)) < 0)
2314 return -ENOMEM;
2315 return 0;
2316 }
2317 #endif
2318
2319 static void __init xfrm_policy_init(void)
2320 {
2321 unsigned int hmask, sz;
2322 int dir;
2323
2324 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2325 sizeof(struct xfrm_dst),
2326 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2327 NULL);
2328
2329 hmask = 8 - 1;
2330 sz = (hmask+1) * sizeof(struct hlist_head);
2331
2332 xfrm_policy_byidx = xfrm_hash_alloc(sz);
2333 xfrm_idx_hmask = hmask;
2334 if (!xfrm_policy_byidx)
2335 panic("XFRM: failed to allocate byidx hash\n");
2336
2337 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2338 struct xfrm_policy_hash *htab;
2339
2340 INIT_HLIST_HEAD(&xfrm_policy_inexact[dir]);
2341
2342 htab = &xfrm_policy_bydst[dir];
2343 htab->table = xfrm_hash_alloc(sz);
2344 htab->hmask = hmask;
2345 if (!htab->table)
2346 panic("XFRM: failed to allocate bydst hash\n");
2347 }
2348
2349 INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task);
2350 register_netdevice_notifier(&xfrm_dev_notifier);
2351 }
2352
2353 void __init xfrm_init(void)
2354 {
2355 #ifdef CONFIG_XFRM_STATISTICS
2356 xfrm_statistics_init();
2357 #endif
2358 xfrm_state_init();
2359 xfrm_policy_init();
2360 xfrm_input_init();
2361 #ifdef CONFIG_XFRM_STATISTICS
2362 xfrm_proc_init();
2363 #endif
2364 }
2365
2366 #ifdef CONFIG_AUDITSYSCALL
2367 static inline void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2368 struct audit_buffer *audit_buf)
2369 {
2370 struct xfrm_sec_ctx *ctx = xp->security;
2371 struct xfrm_selector *sel = &xp->selector;
2372
2373 if (ctx)
2374 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2375 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2376
2377 switch(sel->family) {
2378 case AF_INET:
2379 audit_log_format(audit_buf, " src=" NIPQUAD_FMT,
2380 NIPQUAD(sel->saddr.a4));
2381 if (sel->prefixlen_s != 32)
2382 audit_log_format(audit_buf, " src_prefixlen=%d",
2383 sel->prefixlen_s);
2384 audit_log_format(audit_buf, " dst=" NIPQUAD_FMT,
2385 NIPQUAD(sel->daddr.a4));
2386 if (sel->prefixlen_d != 32)
2387 audit_log_format(audit_buf, " dst_prefixlen=%d",
2388 sel->prefixlen_d);
2389 break;
2390 case AF_INET6:
2391 audit_log_format(audit_buf, " src=" NIP6_FMT,
2392 NIP6(*(struct in6_addr *)sel->saddr.a6));
2393 if (sel->prefixlen_s != 128)
2394 audit_log_format(audit_buf, " src_prefixlen=%d",
2395 sel->prefixlen_s);
2396 audit_log_format(audit_buf, " dst=" NIP6_FMT,
2397 NIP6(*(struct in6_addr *)sel->daddr.a6));
2398 if (sel->prefixlen_d != 128)
2399 audit_log_format(audit_buf, " dst_prefixlen=%d",
2400 sel->prefixlen_d);
2401 break;
2402 }
2403 }
2404
2405 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2406 u32 auid, u32 secid)
2407 {
2408 struct audit_buffer *audit_buf;
2409
2410 if (audit_enabled == 0)
2411 return;
2412 audit_buf = xfrm_audit_start(auid, secid);
2413 if (audit_buf == NULL)
2414 return;
2415 audit_log_format(audit_buf, " op=SPD-add res=%u", result);
2416 xfrm_audit_common_policyinfo(xp, audit_buf);
2417 audit_log_end(audit_buf);
2418 }
2419 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
2420
2421 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
2422 u32 auid, u32 secid)
2423 {
2424 struct audit_buffer *audit_buf;
2425
2426 if (audit_enabled == 0)
2427 return;
2428 audit_buf = xfrm_audit_start(auid, secid);
2429 if (audit_buf == NULL)
2430 return;
2431 audit_log_format(audit_buf, " op=SPD-delete res=%u", result);
2432 xfrm_audit_common_policyinfo(xp, audit_buf);
2433 audit_log_end(audit_buf);
2434 }
2435 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
2436 #endif
2437
2438 #ifdef CONFIG_XFRM_MIGRATE
2439 static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
2440 struct xfrm_selector *sel_tgt)
2441 {
2442 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
2443 if (sel_tgt->family == sel_cmp->family &&
2444 xfrm_addr_cmp(&sel_tgt->daddr, &sel_cmp->daddr,
2445 sel_cmp->family) == 0 &&
2446 xfrm_addr_cmp(&sel_tgt->saddr, &sel_cmp->saddr,
2447 sel_cmp->family) == 0 &&
2448 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
2449 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
2450 return 1;
2451 }
2452 } else {
2453 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
2454 return 1;
2455 }
2456 }
2457 return 0;
2458 }
2459
2460 static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
2461 u8 dir, u8 type)
2462 {
2463 struct xfrm_policy *pol, *ret = NULL;
2464 struct hlist_node *entry;
2465 struct hlist_head *chain;
2466 u32 priority = ~0U;
2467
2468 read_lock_bh(&xfrm_policy_lock);
2469 chain = policy_hash_direct(&sel->daddr, &sel->saddr, sel->family, dir);
2470 hlist_for_each_entry(pol, entry, chain, bydst) {
2471 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2472 pol->type == type) {
2473 ret = pol;
2474 priority = ret->priority;
2475 break;
2476 }
2477 }
2478 chain = &xfrm_policy_inexact[dir];
2479 hlist_for_each_entry(pol, entry, chain, bydst) {
2480 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2481 pol->type == type &&
2482 pol->priority < priority) {
2483 ret = pol;
2484 break;
2485 }
2486 }
2487
2488 if (ret)
2489 xfrm_pol_hold(ret);
2490
2491 read_unlock_bh(&xfrm_policy_lock);
2492
2493 return ret;
2494 }
2495
2496 static int migrate_tmpl_match(struct xfrm_migrate *m, struct xfrm_tmpl *t)
2497 {
2498 int match = 0;
2499
2500 if (t->mode == m->mode && t->id.proto == m->proto &&
2501 (m->reqid == 0 || t->reqid == m->reqid)) {
2502 switch (t->mode) {
2503 case XFRM_MODE_TUNNEL:
2504 case XFRM_MODE_BEET:
2505 if (xfrm_addr_cmp(&t->id.daddr, &m->old_daddr,
2506 m->old_family) == 0 &&
2507 xfrm_addr_cmp(&t->saddr, &m->old_saddr,
2508 m->old_family) == 0) {
2509 match = 1;
2510 }
2511 break;
2512 case XFRM_MODE_TRANSPORT:
2513 /* in case of transport mode, template does not store
2514 any IP addresses, hence we just compare mode and
2515 protocol */
2516 match = 1;
2517 break;
2518 default:
2519 break;
2520 }
2521 }
2522 return match;
2523 }
2524
2525 /* update endpoint address(es) of template(s) */
2526 static int xfrm_policy_migrate(struct xfrm_policy *pol,
2527 struct xfrm_migrate *m, int num_migrate)
2528 {
2529 struct xfrm_migrate *mp;
2530 struct dst_entry *dst;
2531 int i, j, n = 0;
2532
2533 write_lock_bh(&pol->lock);
2534 if (unlikely(pol->dead)) {
2535 /* target policy has been deleted */
2536 write_unlock_bh(&pol->lock);
2537 return -ENOENT;
2538 }
2539
2540 for (i = 0; i < pol->xfrm_nr; i++) {
2541 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
2542 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
2543 continue;
2544 n++;
2545 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
2546 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
2547 continue;
2548 /* update endpoints */
2549 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
2550 sizeof(pol->xfrm_vec[i].id.daddr));
2551 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
2552 sizeof(pol->xfrm_vec[i].saddr));
2553 pol->xfrm_vec[i].encap_family = mp->new_family;
2554 /* flush bundles */
2555 while ((dst = pol->bundles) != NULL) {
2556 pol->bundles = dst->next;
2557 dst_free(dst);
2558 }
2559 }
2560 }
2561
2562 write_unlock_bh(&pol->lock);
2563
2564 if (!n)
2565 return -ENODATA;
2566
2567 return 0;
2568 }
2569
2570 static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
2571 {
2572 int i, j;
2573
2574 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
2575 return -EINVAL;
2576
2577 for (i = 0; i < num_migrate; i++) {
2578 if ((xfrm_addr_cmp(&m[i].old_daddr, &m[i].new_daddr,
2579 m[i].old_family) == 0) &&
2580 (xfrm_addr_cmp(&m[i].old_saddr, &m[i].new_saddr,
2581 m[i].old_family) == 0))
2582 return -EINVAL;
2583 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
2584 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
2585 return -EINVAL;
2586
2587 /* check if there is any duplicated entry */
2588 for (j = i + 1; j < num_migrate; j++) {
2589 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
2590 sizeof(m[i].old_daddr)) &&
2591 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
2592 sizeof(m[i].old_saddr)) &&
2593 m[i].proto == m[j].proto &&
2594 m[i].mode == m[j].mode &&
2595 m[i].reqid == m[j].reqid &&
2596 m[i].old_family == m[j].old_family)
2597 return -EINVAL;
2598 }
2599 }
2600
2601 return 0;
2602 }
2603
2604 int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
2605 struct xfrm_migrate *m, int num_migrate)
2606 {
2607 int i, err, nx_cur = 0, nx_new = 0;
2608 struct xfrm_policy *pol = NULL;
2609 struct xfrm_state *x, *xc;
2610 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
2611 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
2612 struct xfrm_migrate *mp;
2613
2614 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
2615 goto out;
2616
2617 /* Stage 1 - find policy */
2618 if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
2619 err = -ENOENT;
2620 goto out;
2621 }
2622
2623 /* Stage 2 - find and update state(s) */
2624 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
2625 if ((x = xfrm_migrate_state_find(mp))) {
2626 x_cur[nx_cur] = x;
2627 nx_cur++;
2628 if ((xc = xfrm_state_migrate(x, mp))) {
2629 x_new[nx_new] = xc;
2630 nx_new++;
2631 } else {
2632 err = -ENODATA;
2633 goto restore_state;
2634 }
2635 }
2636 }
2637
2638 /* Stage 3 - update policy */
2639 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
2640 goto restore_state;
2641
2642 /* Stage 4 - delete old state(s) */
2643 if (nx_cur) {
2644 xfrm_states_put(x_cur, nx_cur);
2645 xfrm_states_delete(x_cur, nx_cur);
2646 }
2647
2648 /* Stage 5 - announce */
2649 km_migrate(sel, dir, type, m, num_migrate);
2650
2651 xfrm_pol_put(pol);
2652
2653 return 0;
2654 out:
2655 return err;
2656
2657 restore_state:
2658 if (pol)
2659 xfrm_pol_put(pol);
2660 if (nx_cur)
2661 xfrm_states_put(x_cur, nx_cur);
2662 if (nx_new)
2663 xfrm_states_delete(x_new, nx_new);
2664
2665 return err;
2666 }
2667 EXPORT_SYMBOL(xfrm_migrate);
2668 #endif
Linux kernel - Deliverables
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