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x86: arch/x86/mm/init_32.c cleanup
[wrt350n-kernel.git] / net / xfrm / xfrm_policy.c
blob47219f98053f86217027245dc81b42fbdf4d57e5
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 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLERROR);
1515 goto dropdst;
1516 }
1517 }
1518
1519 if (!policy)
1520 goto nopol;
1521
1522 family = dst_orig->ops->family;
1523 pols[0] = policy;
1524 npols ++;
1525 xfrm_nr += pols[0]->xfrm_nr;
1526
1527 err = -ENOENT;
1528 if ((flags & XFRM_LOOKUP_ICMP) && !(policy->flags & XFRM_POLICY_ICMP))
1529 goto error;
1530
1531 policy->curlft.use_time = get_seconds();
1532
1533 switch (policy->action) {
1534 default:
1535 case XFRM_POLICY_BLOCK:
1536 /* Prohibit the flow */
1537 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLBLOCK);
1538 err = -EPERM;
1539 goto error;
1540
1541 case XFRM_POLICY_ALLOW:
1542 #ifndef CONFIG_XFRM_SUB_POLICY
1543 if (policy->xfrm_nr == 0) {
1544 /* Flow passes not transformed. */
1545 xfrm_pol_put(policy);
1546 return 0;
1547 }
1548 #endif
1549
1550 /* Try to find matching bundle.
1551 *
1552 * LATER: help from flow cache. It is optional, this
1553 * is required only for output policy.
1554 */
1555 dst = xfrm_find_bundle(fl, policy, family);
1556 if (IS_ERR(dst)) {
1557 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1558 err = PTR_ERR(dst);
1559 goto error;
1560 }
1561
1562 if (dst)
1563 break;
1564
1565 #ifdef CONFIG_XFRM_SUB_POLICY
1566 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1567 pols[1] = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN,
1568 fl, family,
1569 XFRM_POLICY_OUT);
1570 if (pols[1]) {
1571 if (IS_ERR(pols[1])) {
1572 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLERROR);
1573 err = PTR_ERR(pols[1]);
1574 goto error;
1575 }
1576 if (pols[1]->action == XFRM_POLICY_BLOCK) {
1577 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLBLOCK);
1578 err = -EPERM;
1579 goto error;
1580 }
1581 npols ++;
1582 xfrm_nr += pols[1]->xfrm_nr;
1583 }
1584 }
1585
1586 /*
1587 * Because neither flowi nor bundle information knows about
1588 * transformation template size. On more than one policy usage
1589 * we can realize whether all of them is bypass or not after
1590 * they are searched. See above not-transformed bypass
1591 * is surrounded by non-sub policy configuration, too.
1592 */
1593 if (xfrm_nr == 0) {
1594 /* Flow passes not transformed. */
1595 xfrm_pols_put(pols, npols);
1596 return 0;
1597 }
1598
1599 #endif
1600 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1601
1602 if (unlikely(nx<0)) {
1603 err = nx;
1604 if (err == -EAGAIN && sysctl_xfrm_larval_drop) {
1605 /* EREMOTE tells the caller to generate
1606 * a one-shot blackhole route.
1607 */
1608 XFRM_INC_STATS(LINUX_MIB_XFRMOUTNOSTATES);
1609 xfrm_pol_put(policy);
1610 return -EREMOTE;
1611 }
1612 if (err == -EAGAIN && (flags & XFRM_LOOKUP_WAIT)) {
1613 DECLARE_WAITQUEUE(wait, current);
1614
1615 add_wait_queue(&km_waitq, &wait);
1616 set_current_state(TASK_INTERRUPTIBLE);
1617 schedule();
1618 set_current_state(TASK_RUNNING);
1619 remove_wait_queue(&km_waitq, &wait);
1620
1621 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1622
1623 if (nx == -EAGAIN && signal_pending(current)) {
1624 XFRM_INC_STATS(LINUX_MIB_XFRMOUTNOSTATES);
1625 err = -ERESTART;
1626 goto error;
1627 }
1628 if (nx == -EAGAIN ||
1629 genid != atomic_read(&flow_cache_genid)) {
1630 xfrm_pols_put(pols, npols);
1631 goto restart;
1632 }
1633 err = nx;
1634 }
1635 if (err < 0) {
1636 XFRM_INC_STATS(LINUX_MIB_XFRMOUTNOSTATES);
1637 goto error;
1638 }
1639 }
1640 if (nx == 0) {
1641 /* Flow passes not transformed. */
1642 xfrm_pols_put(pols, npols);
1643 return 0;
1644 }
1645
1646 dst = xfrm_bundle_create(policy, xfrm, nx, fl, dst_orig);
1647 err = PTR_ERR(dst);
1648 if (IS_ERR(dst)) {
1649 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1650 goto error;
1651 }
1652
1653 for (pi = 0; pi < npols; pi++) {
1654 read_lock_bh(&pols[pi]->lock);
1655 pol_dead |= pols[pi]->dead;
1656 read_unlock_bh(&pols[pi]->lock);
1657 }
1658
1659 write_lock_bh(&policy->lock);
1660 if (unlikely(pol_dead || stale_bundle(dst))) {
1661 /* Wow! While we worked on resolving, this
1662 * policy has gone. Retry. It is not paranoia,
1663 * we just cannot enlist new bundle to dead object.
1664 * We can't enlist stable bundles either.
1665 */
1666 write_unlock_bh(&policy->lock);
1667 if (dst)
1668 dst_free(dst);
1669
1670 if (pol_dead)
1671 XFRM_INC_STATS(LINUX_MIB_XFRMOUTPOLDEAD);
1672 else
1673 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1674 err = -EHOSTUNREACH;
1675 goto error;
1676 }
1677
1678 if (npols > 1)
1679 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1680 else
1681 err = xfrm_dst_update_origin(dst, fl);
1682 if (unlikely(err)) {
1683 write_unlock_bh(&policy->lock);
1684 if (dst)
1685 dst_free(dst);
1686 XFRM_INC_STATS(LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1687 goto error;
1688 }
1689
1690 dst->next = policy->bundles;
1691 policy->bundles = dst;
1692 dst_hold(dst);
1693 write_unlock_bh(&policy->lock);
1694 }
1695 *dst_p = dst;
1696 dst_release(dst_orig);
1697 xfrm_pols_put(pols, npols);
1698 return 0;
1699
1700 error:
1701 xfrm_pols_put(pols, npols);
1702 dropdst:
1703 dst_release(dst_orig);
1704 *dst_p = NULL;
1705 return err;
1706
1707 nopol:
1708 err = -ENOENT;
1709 if (flags & XFRM_LOOKUP_ICMP)
1710 goto dropdst;
1711 return 0;
1712 }
1713 EXPORT_SYMBOL(__xfrm_lookup);
1714
1715 int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl,
1716 struct sock *sk, int flags)
1717 {
1718 int err = __xfrm_lookup(dst_p, fl, sk, flags);
1719
1720 if (err == -EREMOTE) {
1721 dst_release(*dst_p);
1722 *dst_p = NULL;
1723 err = -EAGAIN;
1724 }
1725
1726 return err;
1727 }
1728 EXPORT_SYMBOL(xfrm_lookup);
1729
1730 static inline int
1731 xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
1732 {
1733 struct xfrm_state *x;
1734
1735 if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1736 return 0;
1737 x = skb->sp->xvec[idx];
1738 if (!x->type->reject)
1739 return 0;
1740 return x->type->reject(x, skb, fl);
1741 }
1742
1743 /* When skb is transformed back to its "native" form, we have to
1744 * check policy restrictions. At the moment we make this in maximally
1745 * stupid way. Shame on me. :-) Of course, connected sockets must
1746 * have policy cached at them.
1747 */
1748
1749 static inline int
1750 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
1751 unsigned short family)
1752 {
1753 if (xfrm_state_kern(x))
1754 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
1755 return x->id.proto == tmpl->id.proto &&
1756 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1757 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1758 x->props.mode == tmpl->mode &&
1759 ((tmpl->aalgos & (1<<x->props.aalgo)) ||
1760 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1761 !(x->props.mode != XFRM_MODE_TRANSPORT &&
1762 xfrm_state_addr_cmp(tmpl, x, family));
1763 }
1764
1765 /*
1766 * 0 or more than 0 is returned when validation is succeeded (either bypass
1767 * because of optional transport mode, or next index of the mathced secpath
1768 * state with the template.
1769 * -1 is returned when no matching template is found.
1770 * Otherwise "-2 - errored_index" is returned.
1771 */
1772 static inline int
1773 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1774 unsigned short family)
1775 {
1776 int idx = start;
1777
1778 if (tmpl->optional) {
1779 if (tmpl->mode == XFRM_MODE_TRANSPORT)
1780 return start;
1781 } else
1782 start = -1;
1783 for (; idx < sp->len; idx++) {
1784 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1785 return ++idx;
1786 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
1787 if (start == -1)
1788 start = -2-idx;
1789 break;
1790 }
1791 }
1792 return start;
1793 }
1794
1795 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1796 unsigned int family, int reverse)
1797 {
1798 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1799 int err;
1800
1801 if (unlikely(afinfo == NULL))
1802 return -EAFNOSUPPORT;
1803
1804 afinfo->decode_session(skb, fl, reverse);
1805 err = security_xfrm_decode_session(skb, &fl->secid);
1806 xfrm_policy_put_afinfo(afinfo);
1807 return err;
1808 }
1809 EXPORT_SYMBOL(__xfrm_decode_session);
1810
1811 static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
1812 {
1813 for (; k < sp->len; k++) {
1814 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
1815 *idxp = k;
1816 return 1;
1817 }
1818 }
1819
1820 return 0;
1821 }
1822
1823 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
1824 unsigned short family)
1825 {
1826 struct xfrm_policy *pol;
1827 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1828 int npols = 0;
1829 int xfrm_nr;
1830 int pi;
1831 int reverse;
1832 struct flowi fl;
1833 u8 fl_dir;
1834 int xerr_idx = -1;
1835
1836 reverse = dir & ~XFRM_POLICY_MASK;
1837 dir &= XFRM_POLICY_MASK;
1838 fl_dir = policy_to_flow_dir(dir);
1839
1840 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
1841 XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR);
1842 return 0;
1843 }
1844
1845 nf_nat_decode_session(skb, &fl, family);
1846
1847 /* First, check used SA against their selectors. */
1848 if (skb->sp) {
1849 int i;
1850
1851 for (i=skb->sp->len-1; i>=0; i--) {
1852 struct xfrm_state *x = skb->sp->xvec[i];
1853 if (!xfrm_selector_match(&x->sel, &fl, family)) {
1854 XFRM_INC_STATS(LINUX_MIB_XFRMINSTATEMISMATCH);
1855 return 0;
1856 }
1857 }
1858 }
1859
1860 pol = NULL;
1861 if (sk && sk->sk_policy[dir]) {
1862 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
1863 if (IS_ERR(pol)) {
1864 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLERROR);
1865 return 0;
1866 }
1867 }
1868
1869 if (!pol)
1870 pol = flow_cache_lookup(&fl, family, fl_dir,
1871 xfrm_policy_lookup);
1872
1873 if (IS_ERR(pol)) {
1874 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLERROR);
1875 return 0;
1876 }
1877
1878 if (!pol) {
1879 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
1880 xfrm_secpath_reject(xerr_idx, skb, &fl);
1881 XFRM_INC_STATS(LINUX_MIB_XFRMINNOPOLS);
1882 return 0;
1883 }
1884 return 1;
1885 }
1886
1887 pol->curlft.use_time = get_seconds();
1888
1889 pols[0] = pol;
1890 npols ++;
1891 #ifdef CONFIG_XFRM_SUB_POLICY
1892 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1893 pols[1] = xfrm_policy_lookup_bytype(XFRM_POLICY_TYPE_MAIN,
1894 &fl, family,
1895 XFRM_POLICY_IN);
1896 if (pols[1]) {
1897 if (IS_ERR(pols[1])) {
1898 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLERROR);
1899 return 0;
1900 }
1901 pols[1]->curlft.use_time = get_seconds();
1902 npols ++;
1903 }
1904 }
1905 #endif
1906
1907 if (pol->action == XFRM_POLICY_ALLOW) {
1908 struct sec_path *sp;
1909 static struct sec_path dummy;
1910 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
1911 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
1912 struct xfrm_tmpl **tpp = tp;
1913 int ti = 0;
1914 int i, k;
1915
1916 if ((sp = skb->sp) == NULL)
1917 sp = &dummy;
1918
1919 for (pi = 0; pi < npols; pi++) {
1920 if (pols[pi] != pol &&
1921 pols[pi]->action != XFRM_POLICY_ALLOW) {
1922 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLBLOCK);
1923 goto reject;
1924 }
1925 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
1926 XFRM_INC_STATS(LINUX_MIB_XFRMINBUFFERERROR);
1927 goto reject_error;
1928 }
1929 for (i = 0; i < pols[pi]->xfrm_nr; i++)
1930 tpp[ti++] = &pols[pi]->xfrm_vec[i];
1931 }
1932 xfrm_nr = ti;
1933 if (npols > 1) {
1934 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
1935 tpp = stp;
1936 }
1937
1938 /* For each tunnel xfrm, find the first matching tmpl.
1939 * For each tmpl before that, find corresponding xfrm.
1940 * Order is _important_. Later we will implement
1941 * some barriers, but at the moment barriers
1942 * are implied between each two transformations.
1943 */
1944 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
1945 k = xfrm_policy_ok(tpp[i], sp, k, family);
1946 if (k < 0) {
1947 if (k < -1)
1948 /* "-2 - errored_index" returned */
1949 xerr_idx = -(2+k);
1950 XFRM_INC_STATS(LINUX_MIB_XFRMINTMPLMISMATCH);
1951 goto reject;
1952 }
1953 }
1954
1955 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
1956 XFRM_INC_STATS(LINUX_MIB_XFRMINTMPLMISMATCH);
1957 goto reject;
1958 }
1959
1960 xfrm_pols_put(pols, npols);
1961 return 1;
1962 }
1963 XFRM_INC_STATS(LINUX_MIB_XFRMINPOLBLOCK);
1964
1965 reject:
1966 xfrm_secpath_reject(xerr_idx, skb, &fl);
1967 reject_error:
1968 xfrm_pols_put(pols, npols);
1969 return 0;
1970 }
1971 EXPORT_SYMBOL(__xfrm_policy_check);
1972
1973 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1974 {
1975 struct flowi fl;
1976
1977 if (xfrm_decode_session(skb, &fl, family) < 0) {
1978 /* XXX: we should have something like FWDHDRERROR here. */
1979 XFRM_INC_STATS(LINUX_MIB_XFRMINHDRERROR);
1980 return 0;
1981 }
1982
1983 return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0;
1984 }
1985 EXPORT_SYMBOL(__xfrm_route_forward);
1986
1987 /* Optimize later using cookies and generation ids. */
1988
1989 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
1990 {
1991 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
1992 * to "-1" to force all XFRM destinations to get validated by
1993 * dst_ops->check on every use. We do this because when a
1994 * normal route referenced by an XFRM dst is obsoleted we do
1995 * not go looking around for all parent referencing XFRM dsts
1996 * so that we can invalidate them. It is just too much work.
1997 * Instead we make the checks here on every use. For example:
1998 *
1999 * XFRM dst A --> IPv4 dst X
2000 *
2001 * X is the "xdst->route" of A (X is also the "dst->path" of A
2002 * in this example). If X is marked obsolete, "A" will not
2003 * notice. That's what we are validating here via the
2004 * stale_bundle() check.
2005 *
2006 * When a policy's bundle is pruned, we dst_free() the XFRM
2007 * dst which causes it's ->obsolete field to be set to a
2008 * positive non-zero integer. If an XFRM dst has been pruned
2009 * like this, we want to force a new route lookup.
2010 */
2011 if (dst->obsolete < 0 && !stale_bundle(dst))
2012 return dst;
2013
2014 return NULL;
2015 }
2016
2017 static int stale_bundle(struct dst_entry *dst)
2018 {
2019 return !xfrm_bundle_ok(NULL, (struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
2020 }
2021
2022 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2023 {
2024 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2025 dst->dev = dev->nd_net->loopback_dev;
2026 dev_hold(dst->dev);
2027 dev_put(dev);
2028 }
2029 }
2030 EXPORT_SYMBOL(xfrm_dst_ifdown);
2031
2032 static void xfrm_link_failure(struct sk_buff *skb)
2033 {
2034 /* Impossible. Such dst must be popped before reaches point of failure. */
2035 return;
2036 }
2037
2038 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2039 {
2040 if (dst) {
2041 if (dst->obsolete) {
2042 dst_release(dst);
2043 dst = NULL;
2044 }
2045 }
2046 return dst;
2047 }
2048
2049 static void prune_one_bundle(struct xfrm_policy *pol, int (*func)(struct dst_entry *), struct dst_entry **gc_list_p)
2050 {
2051 struct dst_entry *dst, **dstp;
2052
2053 write_lock(&pol->lock);
2054 dstp = &pol->bundles;
2055 while ((dst=*dstp) != NULL) {
2056 if (func(dst)) {
2057 *dstp = dst->next;
2058 dst->next = *gc_list_p;
2059 *gc_list_p = dst;
2060 } else {
2061 dstp = &dst->next;
2062 }
2063 }
2064 write_unlock(&pol->lock);
2065 }
2066
2067 static void xfrm_prune_bundles(int (*func)(struct dst_entry *))
2068 {
2069 struct dst_entry *gc_list = NULL;
2070 int dir;
2071
2072 read_lock_bh(&xfrm_policy_lock);
2073 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2074 struct xfrm_policy *pol;
2075 struct hlist_node *entry;
2076 struct hlist_head *table;
2077 int i;
2078
2079 hlist_for_each_entry(pol, entry,
2080 &xfrm_policy_inexact[dir], bydst)
2081 prune_one_bundle(pol, func, &gc_list);
2082
2083 table = xfrm_policy_bydst[dir].table;
2084 for (i = xfrm_policy_bydst[dir].hmask; i >= 0; i--) {
2085 hlist_for_each_entry(pol, entry, table + i, bydst)
2086 prune_one_bundle(pol, func, &gc_list);
2087 }
2088 }
2089 read_unlock_bh(&xfrm_policy_lock);
2090
2091 while (gc_list) {
2092 struct dst_entry *dst = gc_list;
2093 gc_list = dst->next;
2094 dst_free(dst);
2095 }
2096 }
2097
2098 static int unused_bundle(struct dst_entry *dst)
2099 {
2100 return !atomic_read(&dst->__refcnt);
2101 }
2102
2103 static void __xfrm_garbage_collect(void)
2104 {
2105 xfrm_prune_bundles(unused_bundle);
2106 }
2107
2108 static int xfrm_flush_bundles(void)
2109 {
2110 xfrm_prune_bundles(stale_bundle);
2111 return 0;
2112 }
2113
2114 static void xfrm_init_pmtu(struct dst_entry *dst)
2115 {
2116 do {
2117 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2118 u32 pmtu, route_mtu_cached;
2119
2120 pmtu = dst_mtu(dst->child);
2121 xdst->child_mtu_cached = pmtu;
2122
2123 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2124
2125 route_mtu_cached = dst_mtu(xdst->route);
2126 xdst->route_mtu_cached = route_mtu_cached;
2127
2128 if (pmtu > route_mtu_cached)
2129 pmtu = route_mtu_cached;
2130
2131 dst->metrics[RTAX_MTU-1] = pmtu;
2132 } while ((dst = dst->next));
2133 }
2134
2135 /* Check that the bundle accepts the flow and its components are
2136 * still valid.
2137 */
2138
2139 int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
2140 struct flowi *fl, int family, int strict)
2141 {
2142 struct dst_entry *dst = &first->u.dst;
2143 struct xfrm_dst *last;
2144 u32 mtu;
2145
2146 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2147 (dst->dev && !netif_running(dst->dev)))
2148 return 0;
2149 #ifdef CONFIG_XFRM_SUB_POLICY
2150 if (fl) {
2151 if (first->origin && !flow_cache_uli_match(first->origin, fl))
2152 return 0;
2153 if (first->partner &&
2154 !xfrm_selector_match(first->partner, fl, family))
2155 return 0;
2156 }
2157 #endif
2158
2159 last = NULL;
2160
2161 do {
2162 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2163
2164 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
2165 return 0;
2166 if (fl && pol &&
2167 !security_xfrm_state_pol_flow_match(dst->xfrm, pol, fl))
2168 return 0;
2169 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2170 return 0;
2171 if (xdst->genid != dst->xfrm->genid)
2172 return 0;
2173
2174 if (strict && fl &&
2175 !(dst->xfrm->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
2176 !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
2177 return 0;
2178
2179 mtu = dst_mtu(dst->child);
2180 if (xdst->child_mtu_cached != mtu) {
2181 last = xdst;
2182 xdst->child_mtu_cached = mtu;
2183 }
2184
2185 if (!dst_check(xdst->route, xdst->route_cookie))
2186 return 0;
2187 mtu = dst_mtu(xdst->route);
2188 if (xdst->route_mtu_cached != mtu) {
2189 last = xdst;
2190 xdst->route_mtu_cached = mtu;
2191 }
2192
2193 dst = dst->child;
2194 } while (dst->xfrm);
2195
2196 if (likely(!last))
2197 return 1;
2198
2199 mtu = last->child_mtu_cached;
2200 for (;;) {
2201 dst = &last->u.dst;
2202
2203 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2204 if (mtu > last->route_mtu_cached)
2205 mtu = last->route_mtu_cached;
2206 dst->metrics[RTAX_MTU-1] = mtu;
2207
2208 if (last == first)
2209 break;
2210
2211 last = (struct xfrm_dst *)last->u.dst.next;
2212 last->child_mtu_cached = mtu;
2213 }
2214
2215 return 1;
2216 }
2217
2218 EXPORT_SYMBOL(xfrm_bundle_ok);
2219
2220 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2221 {
2222 int err = 0;
2223 if (unlikely(afinfo == NULL))
2224 return -EINVAL;
2225 if (unlikely(afinfo->family >= NPROTO))
2226 return -EAFNOSUPPORT;
2227 write_lock_bh(&xfrm_policy_afinfo_lock);
2228 if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2229 err = -ENOBUFS;
2230 else {
2231 struct dst_ops *dst_ops = afinfo->dst_ops;
2232 if (likely(dst_ops->kmem_cachep == NULL))
2233 dst_ops->kmem_cachep = xfrm_dst_cache;
2234 if (likely(dst_ops->check == NULL))
2235 dst_ops->check = xfrm_dst_check;
2236 if (likely(dst_ops->negative_advice == NULL))
2237 dst_ops->negative_advice = xfrm_negative_advice;
2238 if (likely(dst_ops->link_failure == NULL))
2239 dst_ops->link_failure = xfrm_link_failure;
2240 if (likely(afinfo->garbage_collect == NULL))
2241 afinfo->garbage_collect = __xfrm_garbage_collect;
2242 xfrm_policy_afinfo[afinfo->family] = afinfo;
2243 }
2244 write_unlock_bh(&xfrm_policy_afinfo_lock);
2245 return err;
2246 }
2247 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2248
2249 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2250 {
2251 int err = 0;
2252 if (unlikely(afinfo == NULL))
2253 return -EINVAL;
2254 if (unlikely(afinfo->family >= NPROTO))
2255 return -EAFNOSUPPORT;
2256 write_lock_bh(&xfrm_policy_afinfo_lock);
2257 if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2258 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2259 err = -EINVAL;
2260 else {
2261 struct dst_ops *dst_ops = afinfo->dst_ops;
2262 xfrm_policy_afinfo[afinfo->family] = NULL;
2263 dst_ops->kmem_cachep = NULL;
2264 dst_ops->check = NULL;
2265 dst_ops->negative_advice = NULL;
2266 dst_ops->link_failure = NULL;
2267 afinfo->garbage_collect = NULL;
2268 }
2269 }
2270 write_unlock_bh(&xfrm_policy_afinfo_lock);
2271 return err;
2272 }
2273 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2274
2275 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
2276 {
2277 struct xfrm_policy_afinfo *afinfo;
2278 if (unlikely(family >= NPROTO))
2279 return NULL;
2280 read_lock(&xfrm_policy_afinfo_lock);
2281 afinfo = xfrm_policy_afinfo[family];
2282 if (unlikely(!afinfo))
2283 read_unlock(&xfrm_policy_afinfo_lock);
2284 return afinfo;
2285 }
2286
2287 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
2288 {
2289 read_unlock(&xfrm_policy_afinfo_lock);
2290 }
2291
2292 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2293 {
2294 struct net_device *dev = ptr;
2295
2296 if (dev->nd_net != &init_net)
2297 return NOTIFY_DONE;
2298
2299 switch (event) {
2300 case NETDEV_DOWN:
2301 xfrm_flush_bundles();
2302 }
2303 return NOTIFY_DONE;
2304 }
2305
2306 static struct notifier_block xfrm_dev_notifier = {
2307 xfrm_dev_event,
2308 NULL,
2309 0
2310 };
2311
2312 #ifdef CONFIG_XFRM_STATISTICS
2313 static int __init xfrm_statistics_init(void)
2314 {
2315 if (snmp_mib_init((void **)xfrm_statistics,
2316 sizeof(struct linux_xfrm_mib)) < 0)
2317 return -ENOMEM;
2318 return 0;
2319 }
2320 #endif
2321
2322 static void __init xfrm_policy_init(void)
2323 {
2324 unsigned int hmask, sz;
2325 int dir;
2326
2327 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2328 sizeof(struct xfrm_dst),
2329 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2330 NULL);
2331
2332 hmask = 8 - 1;
2333 sz = (hmask+1) * sizeof(struct hlist_head);
2334
2335 xfrm_policy_byidx = xfrm_hash_alloc(sz);
2336 xfrm_idx_hmask = hmask;
2337 if (!xfrm_policy_byidx)
2338 panic("XFRM: failed to allocate byidx hash\n");
2339
2340 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2341 struct xfrm_policy_hash *htab;
2342
2343 INIT_HLIST_HEAD(&xfrm_policy_inexact[dir]);
2344
2345 htab = &xfrm_policy_bydst[dir];
2346 htab->table = xfrm_hash_alloc(sz);
2347 htab->hmask = hmask;
2348 if (!htab->table)
2349 panic("XFRM: failed to allocate bydst hash\n");
2350 }
2351
2352 INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task);
2353 register_netdevice_notifier(&xfrm_dev_notifier);
2354 }
2355
2356 void __init xfrm_init(void)
2357 {
2358 #ifdef CONFIG_XFRM_STATISTICS
2359 xfrm_statistics_init();
2360 #endif
2361 xfrm_state_init();
2362 xfrm_policy_init();
2363 xfrm_input_init();
2364 #ifdef CONFIG_XFRM_STATISTICS
2365 xfrm_proc_init();
2366 #endif
2367 }
2368
2369 #ifdef CONFIG_AUDITSYSCALL
2370 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2371 struct audit_buffer *audit_buf)
2372 {
2373 struct xfrm_sec_ctx *ctx = xp->security;
2374 struct xfrm_selector *sel = &xp->selector;
2375
2376 if (ctx)
2377 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2378 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2379
2380 switch(sel->family) {
2381 case AF_INET:
2382 audit_log_format(audit_buf, " src=" NIPQUAD_FMT,
2383 NIPQUAD(sel->saddr.a4));
2384 if (sel->prefixlen_s != 32)
2385 audit_log_format(audit_buf, " src_prefixlen=%d",
2386 sel->prefixlen_s);
2387 audit_log_format(audit_buf, " dst=" NIPQUAD_FMT,
2388 NIPQUAD(sel->daddr.a4));
2389 if (sel->prefixlen_d != 32)
2390 audit_log_format(audit_buf, " dst_prefixlen=%d",
2391 sel->prefixlen_d);
2392 break;
2393 case AF_INET6:
2394 audit_log_format(audit_buf, " src=" NIP6_FMT,
2395 NIP6(*(struct in6_addr *)sel->saddr.a6));
2396 if (sel->prefixlen_s != 128)
2397 audit_log_format(audit_buf, " src_prefixlen=%d",
2398 sel->prefixlen_s);
2399 audit_log_format(audit_buf, " dst=" NIP6_FMT,
2400 NIP6(*(struct in6_addr *)sel->daddr.a6));
2401 if (sel->prefixlen_d != 128)
2402 audit_log_format(audit_buf, " dst_prefixlen=%d",
2403 sel->prefixlen_d);
2404 break;
2405 }
2406 }
2407
2408 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2409 u32 auid, u32 secid)
2410 {
2411 struct audit_buffer *audit_buf;
2412
2413 audit_buf = xfrm_audit_start("SPD-add");
2414 if (audit_buf == NULL)
2415 return;
2416 xfrm_audit_helper_usrinfo(auid, secid, audit_buf);
2417 audit_log_format(audit_buf, " res=%u", result);
2418 xfrm_audit_common_policyinfo(xp, audit_buf);
2419 audit_log_end(audit_buf);
2420 }
2421 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
2422
2423 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
2424 u32 auid, u32 secid)
2425 {
2426 struct audit_buffer *audit_buf;
2427
2428 audit_buf = xfrm_audit_start("SPD-delete");
2429 if (audit_buf == NULL)
2430 return;
2431 xfrm_audit_helper_usrinfo(auid, secid, audit_buf);
2432 audit_log_format(audit_buf, " res=%u", result);
2433 xfrm_audit_common_policyinfo(xp, audit_buf);
2434 audit_log_end(audit_buf);
2435 }
2436 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
2437 #endif
2438
2439 #ifdef CONFIG_XFRM_MIGRATE
2440 static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
2441 struct xfrm_selector *sel_tgt)
2442 {
2443 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
2444 if (sel_tgt->family == sel_cmp->family &&
2445 xfrm_addr_cmp(&sel_tgt->daddr, &sel_cmp->daddr,
2446 sel_cmp->family) == 0 &&
2447 xfrm_addr_cmp(&sel_tgt->saddr, &sel_cmp->saddr,
2448 sel_cmp->family) == 0 &&
2449 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
2450 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
2451 return 1;
2452 }
2453 } else {
2454 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
2455 return 1;
2456 }
2457 }
2458 return 0;
2459 }
2460
2461 static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
2462 u8 dir, u8 type)
2463 {
2464 struct xfrm_policy *pol, *ret = NULL;
2465 struct hlist_node *entry;
2466 struct hlist_head *chain;
2467 u32 priority = ~0U;
2468
2469 read_lock_bh(&xfrm_policy_lock);
2470 chain = policy_hash_direct(&sel->daddr, &sel->saddr, sel->family, dir);
2471 hlist_for_each_entry(pol, entry, chain, bydst) {
2472 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2473 pol->type == type) {
2474 ret = pol;
2475 priority = ret->priority;
2476 break;
2477 }
2478 }
2479 chain = &xfrm_policy_inexact[dir];
2480 hlist_for_each_entry(pol, entry, chain, bydst) {
2481 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2482 pol->type == type &&
2483 pol->priority < priority) {
2484 ret = pol;
2485 break;
2486 }
2487 }
2488
2489 if (ret)
2490 xfrm_pol_hold(ret);
2491
2492 read_unlock_bh(&xfrm_policy_lock);
2493
2494 return ret;
2495 }
2496
2497 static int migrate_tmpl_match(struct xfrm_migrate *m, struct xfrm_tmpl *t)
2498 {
2499 int match = 0;
2500
2501 if (t->mode == m->mode && t->id.proto == m->proto &&
2502 (m->reqid == 0 || t->reqid == m->reqid)) {
2503 switch (t->mode) {
2504 case XFRM_MODE_TUNNEL:
2505 case XFRM_MODE_BEET:
2506 if (xfrm_addr_cmp(&t->id.daddr, &m->old_daddr,
2507 m->old_family) == 0 &&
2508 xfrm_addr_cmp(&t->saddr, &m->old_saddr,
2509 m->old_family) == 0) {
2510 match = 1;
2511 }
2512 break;
2513 case XFRM_MODE_TRANSPORT:
2514 /* in case of transport mode, template does not store
2515 any IP addresses, hence we just compare mode and
2516 protocol */
2517 match = 1;
2518 break;
2519 default:
2520 break;
2521 }
2522 }
2523 return match;
2524 }
2525
2526 /* update endpoint address(es) of template(s) */
2527 static int xfrm_policy_migrate(struct xfrm_policy *pol,
2528 struct xfrm_migrate *m, int num_migrate)
2529 {
2530 struct xfrm_migrate *mp;
2531 struct dst_entry *dst;
2532 int i, j, n = 0;
2533
2534 write_lock_bh(&pol->lock);
2535 if (unlikely(pol->dead)) {
2536 /* target policy has been deleted */
2537 write_unlock_bh(&pol->lock);
2538 return -ENOENT;
2539 }
2540
2541 for (i = 0; i < pol->xfrm_nr; i++) {
2542 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
2543 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
2544 continue;
2545 n++;
2546 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
2547 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
2548 continue;
2549 /* update endpoints */
2550 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
2551 sizeof(pol->xfrm_vec[i].id.daddr));
2552 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
2553 sizeof(pol->xfrm_vec[i].saddr));
2554 pol->xfrm_vec[i].encap_family = mp->new_family;
2555 /* flush bundles */
2556 while ((dst = pol->bundles) != NULL) {
2557 pol->bundles = dst->next;
2558 dst_free(dst);
2559 }
2560 }
2561 }
2562
2563 write_unlock_bh(&pol->lock);
2564
2565 if (!n)
2566 return -ENODATA;
2567
2568 return 0;
2569 }
2570
2571 static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
2572 {
2573 int i, j;
2574
2575 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
2576 return -EINVAL;
2577
2578 for (i = 0; i < num_migrate; i++) {
2579 if ((xfrm_addr_cmp(&m[i].old_daddr, &m[i].new_daddr,
2580 m[i].old_family) == 0) &&
2581 (xfrm_addr_cmp(&m[i].old_saddr, &m[i].new_saddr,
2582 m[i].old_family) == 0))
2583 return -EINVAL;
2584 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
2585 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
2586 return -EINVAL;
2587
2588 /* check if there is any duplicated entry */
2589 for (j = i + 1; j < num_migrate; j++) {
2590 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
2591 sizeof(m[i].old_daddr)) &&
2592 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
2593 sizeof(m[i].old_saddr)) &&
2594 m[i].proto == m[j].proto &&
2595 m[i].mode == m[j].mode &&
2596 m[i].reqid == m[j].reqid &&
2597 m[i].old_family == m[j].old_family)
2598 return -EINVAL;
2599 }
2600 }
2601
2602 return 0;
2603 }
2604
2605 int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
2606 struct xfrm_migrate *m, int num_migrate)
2607 {
2608 int i, err, nx_cur = 0, nx_new = 0;
2609 struct xfrm_policy *pol = NULL;
2610 struct xfrm_state *x, *xc;
2611 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
2612 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
2613 struct xfrm_migrate *mp;
2614
2615 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
2616 goto out;
2617
2618 /* Stage 1 - find policy */
2619 if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
2620 err = -ENOENT;
2621 goto out;
2622 }
2623
2624 /* Stage 2 - find and update state(s) */
2625 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
2626 if ((x = xfrm_migrate_state_find(mp))) {
2627 x_cur[nx_cur] = x;
2628 nx_cur++;
2629 if ((xc = xfrm_state_migrate(x, mp))) {
2630 x_new[nx_new] = xc;
2631 nx_new++;
2632 } else {
2633 err = -ENODATA;
2634 goto restore_state;
2635 }
2636 }
2637 }
2638
2639 /* Stage 3 - update policy */
2640 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
2641 goto restore_state;
2642
2643 /* Stage 4 - delete old state(s) */
2644 if (nx_cur) {
2645 xfrm_states_put(x_cur, nx_cur);
2646 xfrm_states_delete(x_cur, nx_cur);
2647 }
2648
2649 /* Stage 5 - announce */
2650 km_migrate(sel, dir, type, m, num_migrate);
2651
2652 xfrm_pol_put(pol);
2653
2654 return 0;
2655 out:
2656 return err;
2657
2658 restore_state:
2659 if (pol)
2660 xfrm_pol_put(pol);
2661 if (nx_cur)
2662 xfrm_states_put(x_cur, nx_cur);
2663 if (nx_new)
2664 xfrm_states_delete(x_new, nx_new);
2665
2666 return err;
2667 }
2668 EXPORT_SYMBOL(xfrm_migrate);
2669 #endif
WRT350N Kernel Patches