xref: /linux/net/xfrm/xfrm_policy.c (revision 293d5b43948309434568f4dcbb36cce4c3c51bd5)
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/flow.h>
30 #include <net/xfrm.h>
31 #include <net/ip.h>
32 #ifdef CONFIG_XFRM_STATISTICS
33 #include <net/snmp.h>
34 #endif
35 
36 #include "xfrm_hash.h"
37 
38 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
39 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
40 #define XFRM_MAX_QUEUE_LEN	100
41 
42 struct xfrm_flo {
43 	struct dst_entry *dst_orig;
44 	u8 flags;
45 };
46 
47 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
48 static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
49 						__read_mostly;
50 
51 static struct kmem_cache *xfrm_dst_cache __read_mostly;
52 
53 static void xfrm_init_pmtu(struct dst_entry *dst);
54 static int stale_bundle(struct dst_entry *dst);
55 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
56 static void xfrm_policy_queue_process(unsigned long arg);
57 
58 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
59 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
60 						int dir);
61 
62 static inline bool
63 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
64 {
65 	const struct flowi4 *fl4 = &fl->u.ip4;
66 
67 	return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
68 		addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
69 		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
70 		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
71 		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
72 		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
73 }
74 
75 static inline bool
76 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
77 {
78 	const struct flowi6 *fl6 = &fl->u.ip6;
79 
80 	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
81 		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
82 		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
83 		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
84 		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
85 		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
86 }
87 
88 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
89 			 unsigned short family)
90 {
91 	switch (family) {
92 	case AF_INET:
93 		return __xfrm4_selector_match(sel, fl);
94 	case AF_INET6:
95 		return __xfrm6_selector_match(sel, fl);
96 	}
97 	return false;
98 }
99 
100 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
101 {
102 	struct xfrm_policy_afinfo *afinfo;
103 
104 	if (unlikely(family >= NPROTO))
105 		return NULL;
106 	rcu_read_lock();
107 	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
108 	if (unlikely(!afinfo))
109 		rcu_read_unlock();
110 	return afinfo;
111 }
112 
113 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
114 {
115 	rcu_read_unlock();
116 }
117 
118 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net,
119 						  int tos, int oif,
120 						  const xfrm_address_t *saddr,
121 						  const xfrm_address_t *daddr,
122 						  int family)
123 {
124 	struct xfrm_policy_afinfo *afinfo;
125 	struct dst_entry *dst;
126 
127 	afinfo = xfrm_policy_get_afinfo(family);
128 	if (unlikely(afinfo == NULL))
129 		return ERR_PTR(-EAFNOSUPPORT);
130 
131 	dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr);
132 
133 	xfrm_policy_put_afinfo(afinfo);
134 
135 	return dst;
136 }
137 
138 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
139 						int tos, int oif,
140 						xfrm_address_t *prev_saddr,
141 						xfrm_address_t *prev_daddr,
142 						int family)
143 {
144 	struct net *net = xs_net(x);
145 	xfrm_address_t *saddr = &x->props.saddr;
146 	xfrm_address_t *daddr = &x->id.daddr;
147 	struct dst_entry *dst;
148 
149 	if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
150 		saddr = x->coaddr;
151 		daddr = prev_daddr;
152 	}
153 	if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
154 		saddr = prev_saddr;
155 		daddr = x->coaddr;
156 	}
157 
158 	dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family);
159 
160 	if (!IS_ERR(dst)) {
161 		if (prev_saddr != saddr)
162 			memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
163 		if (prev_daddr != daddr)
164 			memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
165 	}
166 
167 	return dst;
168 }
169 
170 static inline unsigned long make_jiffies(long secs)
171 {
172 	if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
173 		return MAX_SCHEDULE_TIMEOUT-1;
174 	else
175 		return secs*HZ;
176 }
177 
178 static void xfrm_policy_timer(unsigned long data)
179 {
180 	struct xfrm_policy *xp = (struct xfrm_policy *)data;
181 	unsigned long now = get_seconds();
182 	long next = LONG_MAX;
183 	int warn = 0;
184 	int dir;
185 
186 	read_lock(&xp->lock);
187 
188 	if (unlikely(xp->walk.dead))
189 		goto out;
190 
191 	dir = xfrm_policy_id2dir(xp->index);
192 
193 	if (xp->lft.hard_add_expires_seconds) {
194 		long tmo = xp->lft.hard_add_expires_seconds +
195 			xp->curlft.add_time - now;
196 		if (tmo <= 0)
197 			goto expired;
198 		if (tmo < next)
199 			next = tmo;
200 	}
201 	if (xp->lft.hard_use_expires_seconds) {
202 		long tmo = xp->lft.hard_use_expires_seconds +
203 			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
204 		if (tmo <= 0)
205 			goto expired;
206 		if (tmo < next)
207 			next = tmo;
208 	}
209 	if (xp->lft.soft_add_expires_seconds) {
210 		long tmo = xp->lft.soft_add_expires_seconds +
211 			xp->curlft.add_time - now;
212 		if (tmo <= 0) {
213 			warn = 1;
214 			tmo = XFRM_KM_TIMEOUT;
215 		}
216 		if (tmo < next)
217 			next = tmo;
218 	}
219 	if (xp->lft.soft_use_expires_seconds) {
220 		long tmo = xp->lft.soft_use_expires_seconds +
221 			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
222 		if (tmo <= 0) {
223 			warn = 1;
224 			tmo = XFRM_KM_TIMEOUT;
225 		}
226 		if (tmo < next)
227 			next = tmo;
228 	}
229 
230 	if (warn)
231 		km_policy_expired(xp, dir, 0, 0);
232 	if (next != LONG_MAX &&
233 	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
234 		xfrm_pol_hold(xp);
235 
236 out:
237 	read_unlock(&xp->lock);
238 	xfrm_pol_put(xp);
239 	return;
240 
241 expired:
242 	read_unlock(&xp->lock);
243 	if (!xfrm_policy_delete(xp, dir))
244 		km_policy_expired(xp, dir, 1, 0);
245 	xfrm_pol_put(xp);
246 }
247 
248 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
249 {
250 	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
251 
252 	if (unlikely(pol->walk.dead))
253 		flo = NULL;
254 	else
255 		xfrm_pol_hold(pol);
256 
257 	return flo;
258 }
259 
260 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
261 {
262 	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
263 
264 	return !pol->walk.dead;
265 }
266 
267 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
268 {
269 	xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
270 }
271 
272 static const struct flow_cache_ops xfrm_policy_fc_ops = {
273 	.get = xfrm_policy_flo_get,
274 	.check = xfrm_policy_flo_check,
275 	.delete = xfrm_policy_flo_delete,
276 };
277 
278 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
279  * SPD calls.
280  */
281 
282 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
283 {
284 	struct xfrm_policy *policy;
285 
286 	policy = kzalloc(sizeof(struct xfrm_policy), gfp);
287 
288 	if (policy) {
289 		write_pnet(&policy->xp_net, net);
290 		INIT_LIST_HEAD(&policy->walk.all);
291 		INIT_HLIST_NODE(&policy->bydst);
292 		INIT_HLIST_NODE(&policy->byidx);
293 		rwlock_init(&policy->lock);
294 		atomic_set(&policy->refcnt, 1);
295 		skb_queue_head_init(&policy->polq.hold_queue);
296 		setup_timer(&policy->timer, xfrm_policy_timer,
297 				(unsigned long)policy);
298 		setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
299 			    (unsigned long)policy);
300 		policy->flo.ops = &xfrm_policy_fc_ops;
301 	}
302 	return policy;
303 }
304 EXPORT_SYMBOL(xfrm_policy_alloc);
305 
306 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
307 {
308 	struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
309 
310 	security_xfrm_policy_free(policy->security);
311 	kfree(policy);
312 }
313 
314 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
315 
316 void xfrm_policy_destroy(struct xfrm_policy *policy)
317 {
318 	BUG_ON(!policy->walk.dead);
319 
320 	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
321 		BUG();
322 
323 	call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
324 }
325 EXPORT_SYMBOL(xfrm_policy_destroy);
326 
327 /* Rule must be locked. Release descentant resources, announce
328  * entry dead. The rule must be unlinked from lists to the moment.
329  */
330 
331 static void xfrm_policy_kill(struct xfrm_policy *policy)
332 {
333 	policy->walk.dead = 1;
334 
335 	atomic_inc(&policy->genid);
336 
337 	if (del_timer(&policy->polq.hold_timer))
338 		xfrm_pol_put(policy);
339 	skb_queue_purge(&policy->polq.hold_queue);
340 
341 	if (del_timer(&policy->timer))
342 		xfrm_pol_put(policy);
343 
344 	xfrm_pol_put(policy);
345 }
346 
347 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
348 
349 static inline unsigned int idx_hash(struct net *net, u32 index)
350 {
351 	return __idx_hash(index, net->xfrm.policy_idx_hmask);
352 }
353 
354 /* calculate policy hash thresholds */
355 static void __get_hash_thresh(struct net *net,
356 			      unsigned short family, int dir,
357 			      u8 *dbits, u8 *sbits)
358 {
359 	switch (family) {
360 	case AF_INET:
361 		*dbits = net->xfrm.policy_bydst[dir].dbits4;
362 		*sbits = net->xfrm.policy_bydst[dir].sbits4;
363 		break;
364 
365 	case AF_INET6:
366 		*dbits = net->xfrm.policy_bydst[dir].dbits6;
367 		*sbits = net->xfrm.policy_bydst[dir].sbits6;
368 		break;
369 
370 	default:
371 		*dbits = 0;
372 		*sbits = 0;
373 	}
374 }
375 
376 static struct hlist_head *policy_hash_bysel(struct net *net,
377 					    const struct xfrm_selector *sel,
378 					    unsigned short family, int dir)
379 {
380 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
381 	unsigned int hash;
382 	u8 dbits;
383 	u8 sbits;
384 
385 	__get_hash_thresh(net, family, dir, &dbits, &sbits);
386 	hash = __sel_hash(sel, family, hmask, dbits, sbits);
387 
388 	return (hash == hmask + 1 ?
389 		&net->xfrm.policy_inexact[dir] :
390 		net->xfrm.policy_bydst[dir].table + hash);
391 }
392 
393 static struct hlist_head *policy_hash_direct(struct net *net,
394 					     const xfrm_address_t *daddr,
395 					     const xfrm_address_t *saddr,
396 					     unsigned short family, int dir)
397 {
398 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
399 	unsigned int hash;
400 	u8 dbits;
401 	u8 sbits;
402 
403 	__get_hash_thresh(net, family, dir, &dbits, &sbits);
404 	hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
405 
406 	return net->xfrm.policy_bydst[dir].table + hash;
407 }
408 
409 static void xfrm_dst_hash_transfer(struct net *net,
410 				   struct hlist_head *list,
411 				   struct hlist_head *ndsttable,
412 				   unsigned int nhashmask,
413 				   int dir)
414 {
415 	struct hlist_node *tmp, *entry0 = NULL;
416 	struct xfrm_policy *pol;
417 	unsigned int h0 = 0;
418 	u8 dbits;
419 	u8 sbits;
420 
421 redo:
422 	hlist_for_each_entry_safe(pol, tmp, list, bydst) {
423 		unsigned int h;
424 
425 		__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
426 		h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
427 				pol->family, nhashmask, dbits, sbits);
428 		if (!entry0) {
429 			hlist_del(&pol->bydst);
430 			hlist_add_head(&pol->bydst, ndsttable+h);
431 			h0 = h;
432 		} else {
433 			if (h != h0)
434 				continue;
435 			hlist_del(&pol->bydst);
436 			hlist_add_behind(&pol->bydst, entry0);
437 		}
438 		entry0 = &pol->bydst;
439 	}
440 	if (!hlist_empty(list)) {
441 		entry0 = NULL;
442 		goto redo;
443 	}
444 }
445 
446 static void xfrm_idx_hash_transfer(struct hlist_head *list,
447 				   struct hlist_head *nidxtable,
448 				   unsigned int nhashmask)
449 {
450 	struct hlist_node *tmp;
451 	struct xfrm_policy *pol;
452 
453 	hlist_for_each_entry_safe(pol, tmp, list, byidx) {
454 		unsigned int h;
455 
456 		h = __idx_hash(pol->index, nhashmask);
457 		hlist_add_head(&pol->byidx, nidxtable+h);
458 	}
459 }
460 
461 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
462 {
463 	return ((old_hmask + 1) << 1) - 1;
464 }
465 
466 static void xfrm_bydst_resize(struct net *net, int dir)
467 {
468 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
469 	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
470 	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
471 	struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
472 	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
473 	int i;
474 
475 	if (!ndst)
476 		return;
477 
478 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
479 
480 	for (i = hmask; i >= 0; i--)
481 		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
482 
483 	net->xfrm.policy_bydst[dir].table = ndst;
484 	net->xfrm.policy_bydst[dir].hmask = nhashmask;
485 
486 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
487 
488 	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
489 }
490 
491 static void xfrm_byidx_resize(struct net *net, int total)
492 {
493 	unsigned int hmask = net->xfrm.policy_idx_hmask;
494 	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
495 	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
496 	struct hlist_head *oidx = net->xfrm.policy_byidx;
497 	struct hlist_head *nidx = xfrm_hash_alloc(nsize);
498 	int i;
499 
500 	if (!nidx)
501 		return;
502 
503 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
504 
505 	for (i = hmask; i >= 0; i--)
506 		xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
507 
508 	net->xfrm.policy_byidx = nidx;
509 	net->xfrm.policy_idx_hmask = nhashmask;
510 
511 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
512 
513 	xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
514 }
515 
516 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
517 {
518 	unsigned int cnt = net->xfrm.policy_count[dir];
519 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
520 
521 	if (total)
522 		*total += cnt;
523 
524 	if ((hmask + 1) < xfrm_policy_hashmax &&
525 	    cnt > hmask)
526 		return 1;
527 
528 	return 0;
529 }
530 
531 static inline int xfrm_byidx_should_resize(struct net *net, int total)
532 {
533 	unsigned int hmask = net->xfrm.policy_idx_hmask;
534 
535 	if ((hmask + 1) < xfrm_policy_hashmax &&
536 	    total > hmask)
537 		return 1;
538 
539 	return 0;
540 }
541 
542 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
543 {
544 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
545 	si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
546 	si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
547 	si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
548 	si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
549 	si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
550 	si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
551 	si->spdhcnt = net->xfrm.policy_idx_hmask;
552 	si->spdhmcnt = xfrm_policy_hashmax;
553 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
554 }
555 EXPORT_SYMBOL(xfrm_spd_getinfo);
556 
557 static DEFINE_MUTEX(hash_resize_mutex);
558 static void xfrm_hash_resize(struct work_struct *work)
559 {
560 	struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
561 	int dir, total;
562 
563 	mutex_lock(&hash_resize_mutex);
564 
565 	total = 0;
566 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
567 		if (xfrm_bydst_should_resize(net, dir, &total))
568 			xfrm_bydst_resize(net, dir);
569 	}
570 	if (xfrm_byidx_should_resize(net, total))
571 		xfrm_byidx_resize(net, total);
572 
573 	mutex_unlock(&hash_resize_mutex);
574 }
575 
576 static void xfrm_hash_rebuild(struct work_struct *work)
577 {
578 	struct net *net = container_of(work, struct net,
579 				       xfrm.policy_hthresh.work);
580 	unsigned int hmask;
581 	struct xfrm_policy *pol;
582 	struct xfrm_policy *policy;
583 	struct hlist_head *chain;
584 	struct hlist_head *odst;
585 	struct hlist_node *newpos;
586 	int i;
587 	int dir;
588 	unsigned seq;
589 	u8 lbits4, rbits4, lbits6, rbits6;
590 
591 	mutex_lock(&hash_resize_mutex);
592 
593 	/* read selector prefixlen thresholds */
594 	do {
595 		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
596 
597 		lbits4 = net->xfrm.policy_hthresh.lbits4;
598 		rbits4 = net->xfrm.policy_hthresh.rbits4;
599 		lbits6 = net->xfrm.policy_hthresh.lbits6;
600 		rbits6 = net->xfrm.policy_hthresh.rbits6;
601 	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
602 
603 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
604 
605 	/* reset the bydst and inexact table in all directions */
606 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
607 		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
608 		hmask = net->xfrm.policy_bydst[dir].hmask;
609 		odst = net->xfrm.policy_bydst[dir].table;
610 		for (i = hmask; i >= 0; i--)
611 			INIT_HLIST_HEAD(odst + i);
612 		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
613 			/* dir out => dst = remote, src = local */
614 			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
615 			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
616 			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
617 			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
618 		} else {
619 			/* dir in/fwd => dst = local, src = remote */
620 			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
621 			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
622 			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
623 			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
624 		}
625 	}
626 
627 	/* re-insert all policies by order of creation */
628 	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
629 		newpos = NULL;
630 		chain = policy_hash_bysel(net, &policy->selector,
631 					  policy->family,
632 					  xfrm_policy_id2dir(policy->index));
633 		hlist_for_each_entry(pol, chain, bydst) {
634 			if (policy->priority >= pol->priority)
635 				newpos = &pol->bydst;
636 			else
637 				break;
638 		}
639 		if (newpos)
640 			hlist_add_behind(&policy->bydst, newpos);
641 		else
642 			hlist_add_head(&policy->bydst, chain);
643 	}
644 
645 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
646 
647 	mutex_unlock(&hash_resize_mutex);
648 }
649 
650 void xfrm_policy_hash_rebuild(struct net *net)
651 {
652 	schedule_work(&net->xfrm.policy_hthresh.work);
653 }
654 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
655 
656 /* Generate new index... KAME seems to generate them ordered by cost
657  * of an absolute inpredictability of ordering of rules. This will not pass. */
658 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
659 {
660 	static u32 idx_generator;
661 
662 	for (;;) {
663 		struct hlist_head *list;
664 		struct xfrm_policy *p;
665 		u32 idx;
666 		int found;
667 
668 		if (!index) {
669 			idx = (idx_generator | dir);
670 			idx_generator += 8;
671 		} else {
672 			idx = index;
673 			index = 0;
674 		}
675 
676 		if (idx == 0)
677 			idx = 8;
678 		list = net->xfrm.policy_byidx + idx_hash(net, idx);
679 		found = 0;
680 		hlist_for_each_entry(p, list, byidx) {
681 			if (p->index == idx) {
682 				found = 1;
683 				break;
684 			}
685 		}
686 		if (!found)
687 			return idx;
688 	}
689 }
690 
691 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
692 {
693 	u32 *p1 = (u32 *) s1;
694 	u32 *p2 = (u32 *) s2;
695 	int len = sizeof(struct xfrm_selector) / sizeof(u32);
696 	int i;
697 
698 	for (i = 0; i < len; i++) {
699 		if (p1[i] != p2[i])
700 			return 1;
701 	}
702 
703 	return 0;
704 }
705 
706 static void xfrm_policy_requeue(struct xfrm_policy *old,
707 				struct xfrm_policy *new)
708 {
709 	struct xfrm_policy_queue *pq = &old->polq;
710 	struct sk_buff_head list;
711 
712 	if (skb_queue_empty(&pq->hold_queue))
713 		return;
714 
715 	__skb_queue_head_init(&list);
716 
717 	spin_lock_bh(&pq->hold_queue.lock);
718 	skb_queue_splice_init(&pq->hold_queue, &list);
719 	if (del_timer(&pq->hold_timer))
720 		xfrm_pol_put(old);
721 	spin_unlock_bh(&pq->hold_queue.lock);
722 
723 	pq = &new->polq;
724 
725 	spin_lock_bh(&pq->hold_queue.lock);
726 	skb_queue_splice(&list, &pq->hold_queue);
727 	pq->timeout = XFRM_QUEUE_TMO_MIN;
728 	if (!mod_timer(&pq->hold_timer, jiffies))
729 		xfrm_pol_hold(new);
730 	spin_unlock_bh(&pq->hold_queue.lock);
731 }
732 
733 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
734 				   struct xfrm_policy *pol)
735 {
736 	u32 mark = policy->mark.v & policy->mark.m;
737 
738 	if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
739 		return true;
740 
741 	if ((mark & pol->mark.m) == pol->mark.v &&
742 	    policy->priority == pol->priority)
743 		return true;
744 
745 	return false;
746 }
747 
748 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
749 {
750 	struct net *net = xp_net(policy);
751 	struct xfrm_policy *pol;
752 	struct xfrm_policy *delpol;
753 	struct hlist_head *chain;
754 	struct hlist_node *newpos;
755 
756 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
757 	chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
758 	delpol = NULL;
759 	newpos = NULL;
760 	hlist_for_each_entry(pol, chain, bydst) {
761 		if (pol->type == policy->type &&
762 		    !selector_cmp(&pol->selector, &policy->selector) &&
763 		    xfrm_policy_mark_match(policy, pol) &&
764 		    xfrm_sec_ctx_match(pol->security, policy->security) &&
765 		    !WARN_ON(delpol)) {
766 			if (excl) {
767 				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
768 				return -EEXIST;
769 			}
770 			delpol = pol;
771 			if (policy->priority > pol->priority)
772 				continue;
773 		} else if (policy->priority >= pol->priority) {
774 			newpos = &pol->bydst;
775 			continue;
776 		}
777 		if (delpol)
778 			break;
779 	}
780 	if (newpos)
781 		hlist_add_behind(&policy->bydst, newpos);
782 	else
783 		hlist_add_head(&policy->bydst, chain);
784 	__xfrm_policy_link(policy, dir);
785 	atomic_inc(&net->xfrm.flow_cache_genid);
786 
787 	/* After previous checking, family can either be AF_INET or AF_INET6 */
788 	if (policy->family == AF_INET)
789 		rt_genid_bump_ipv4(net);
790 	else
791 		rt_genid_bump_ipv6(net);
792 
793 	if (delpol) {
794 		xfrm_policy_requeue(delpol, policy);
795 		__xfrm_policy_unlink(delpol, dir);
796 	}
797 	policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
798 	hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
799 	policy->curlft.add_time = get_seconds();
800 	policy->curlft.use_time = 0;
801 	if (!mod_timer(&policy->timer, jiffies + HZ))
802 		xfrm_pol_hold(policy);
803 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
804 
805 	if (delpol)
806 		xfrm_policy_kill(delpol);
807 	else if (xfrm_bydst_should_resize(net, dir, NULL))
808 		schedule_work(&net->xfrm.policy_hash_work);
809 
810 	return 0;
811 }
812 EXPORT_SYMBOL(xfrm_policy_insert);
813 
814 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
815 					  int dir, struct xfrm_selector *sel,
816 					  struct xfrm_sec_ctx *ctx, int delete,
817 					  int *err)
818 {
819 	struct xfrm_policy *pol, *ret;
820 	struct hlist_head *chain;
821 
822 	*err = 0;
823 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
824 	chain = policy_hash_bysel(net, sel, sel->family, dir);
825 	ret = NULL;
826 	hlist_for_each_entry(pol, chain, bydst) {
827 		if (pol->type == type &&
828 		    (mark & pol->mark.m) == pol->mark.v &&
829 		    !selector_cmp(sel, &pol->selector) &&
830 		    xfrm_sec_ctx_match(ctx, pol->security)) {
831 			xfrm_pol_hold(pol);
832 			if (delete) {
833 				*err = security_xfrm_policy_delete(
834 								pol->security);
835 				if (*err) {
836 					write_unlock_bh(&net->xfrm.xfrm_policy_lock);
837 					return pol;
838 				}
839 				__xfrm_policy_unlink(pol, dir);
840 			}
841 			ret = pol;
842 			break;
843 		}
844 	}
845 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
846 
847 	if (ret && delete)
848 		xfrm_policy_kill(ret);
849 	return ret;
850 }
851 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
852 
853 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
854 				     int dir, u32 id, int delete, int *err)
855 {
856 	struct xfrm_policy *pol, *ret;
857 	struct hlist_head *chain;
858 
859 	*err = -ENOENT;
860 	if (xfrm_policy_id2dir(id) != dir)
861 		return NULL;
862 
863 	*err = 0;
864 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
865 	chain = net->xfrm.policy_byidx + idx_hash(net, id);
866 	ret = NULL;
867 	hlist_for_each_entry(pol, chain, byidx) {
868 		if (pol->type == type && pol->index == id &&
869 		    (mark & pol->mark.m) == pol->mark.v) {
870 			xfrm_pol_hold(pol);
871 			if (delete) {
872 				*err = security_xfrm_policy_delete(
873 								pol->security);
874 				if (*err) {
875 					write_unlock_bh(&net->xfrm.xfrm_policy_lock);
876 					return pol;
877 				}
878 				__xfrm_policy_unlink(pol, dir);
879 			}
880 			ret = pol;
881 			break;
882 		}
883 	}
884 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
885 
886 	if (ret && delete)
887 		xfrm_policy_kill(ret);
888 	return ret;
889 }
890 EXPORT_SYMBOL(xfrm_policy_byid);
891 
892 #ifdef CONFIG_SECURITY_NETWORK_XFRM
893 static inline int
894 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
895 {
896 	int dir, err = 0;
897 
898 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
899 		struct xfrm_policy *pol;
900 		int i;
901 
902 		hlist_for_each_entry(pol,
903 				     &net->xfrm.policy_inexact[dir], bydst) {
904 			if (pol->type != type)
905 				continue;
906 			err = security_xfrm_policy_delete(pol->security);
907 			if (err) {
908 				xfrm_audit_policy_delete(pol, 0, task_valid);
909 				return err;
910 			}
911 		}
912 		for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
913 			hlist_for_each_entry(pol,
914 					     net->xfrm.policy_bydst[dir].table + i,
915 					     bydst) {
916 				if (pol->type != type)
917 					continue;
918 				err = security_xfrm_policy_delete(
919 								pol->security);
920 				if (err) {
921 					xfrm_audit_policy_delete(pol, 0,
922 								 task_valid);
923 					return err;
924 				}
925 			}
926 		}
927 	}
928 	return err;
929 }
930 #else
931 static inline int
932 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
933 {
934 	return 0;
935 }
936 #endif
937 
938 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
939 {
940 	int dir, err = 0, cnt = 0;
941 
942 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
943 
944 	err = xfrm_policy_flush_secctx_check(net, type, task_valid);
945 	if (err)
946 		goto out;
947 
948 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
949 		struct xfrm_policy *pol;
950 		int i;
951 
952 	again1:
953 		hlist_for_each_entry(pol,
954 				     &net->xfrm.policy_inexact[dir], bydst) {
955 			if (pol->type != type)
956 				continue;
957 			__xfrm_policy_unlink(pol, dir);
958 			write_unlock_bh(&net->xfrm.xfrm_policy_lock);
959 			cnt++;
960 
961 			xfrm_audit_policy_delete(pol, 1, task_valid);
962 
963 			xfrm_policy_kill(pol);
964 
965 			write_lock_bh(&net->xfrm.xfrm_policy_lock);
966 			goto again1;
967 		}
968 
969 		for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
970 	again2:
971 			hlist_for_each_entry(pol,
972 					     net->xfrm.policy_bydst[dir].table + i,
973 					     bydst) {
974 				if (pol->type != type)
975 					continue;
976 				__xfrm_policy_unlink(pol, dir);
977 				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
978 				cnt++;
979 
980 				xfrm_audit_policy_delete(pol, 1, task_valid);
981 				xfrm_policy_kill(pol);
982 
983 				write_lock_bh(&net->xfrm.xfrm_policy_lock);
984 				goto again2;
985 			}
986 		}
987 
988 	}
989 	if (!cnt)
990 		err = -ESRCH;
991 out:
992 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
993 	return err;
994 }
995 EXPORT_SYMBOL(xfrm_policy_flush);
996 
997 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
998 		     int (*func)(struct xfrm_policy *, int, int, void*),
999 		     void *data)
1000 {
1001 	struct xfrm_policy *pol;
1002 	struct xfrm_policy_walk_entry *x;
1003 	int error = 0;
1004 
1005 	if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1006 	    walk->type != XFRM_POLICY_TYPE_ANY)
1007 		return -EINVAL;
1008 
1009 	if (list_empty(&walk->walk.all) && walk->seq != 0)
1010 		return 0;
1011 
1012 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1013 	if (list_empty(&walk->walk.all))
1014 		x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1015 	else
1016 		x = list_first_entry(&walk->walk.all,
1017 				     struct xfrm_policy_walk_entry, all);
1018 
1019 	list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1020 		if (x->dead)
1021 			continue;
1022 		pol = container_of(x, struct xfrm_policy, walk);
1023 		if (walk->type != XFRM_POLICY_TYPE_ANY &&
1024 		    walk->type != pol->type)
1025 			continue;
1026 		error = func(pol, xfrm_policy_id2dir(pol->index),
1027 			     walk->seq, data);
1028 		if (error) {
1029 			list_move_tail(&walk->walk.all, &x->all);
1030 			goto out;
1031 		}
1032 		walk->seq++;
1033 	}
1034 	if (walk->seq == 0) {
1035 		error = -ENOENT;
1036 		goto out;
1037 	}
1038 	list_del_init(&walk->walk.all);
1039 out:
1040 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1041 	return error;
1042 }
1043 EXPORT_SYMBOL(xfrm_policy_walk);
1044 
1045 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1046 {
1047 	INIT_LIST_HEAD(&walk->walk.all);
1048 	walk->walk.dead = 1;
1049 	walk->type = type;
1050 	walk->seq = 0;
1051 }
1052 EXPORT_SYMBOL(xfrm_policy_walk_init);
1053 
1054 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1055 {
1056 	if (list_empty(&walk->walk.all))
1057 		return;
1058 
1059 	write_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1060 	list_del(&walk->walk.all);
1061 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1062 }
1063 EXPORT_SYMBOL(xfrm_policy_walk_done);
1064 
1065 /*
1066  * Find policy to apply to this flow.
1067  *
1068  * Returns 0 if policy found, else an -errno.
1069  */
1070 static int xfrm_policy_match(const struct xfrm_policy *pol,
1071 			     const struct flowi *fl,
1072 			     u8 type, u16 family, int dir)
1073 {
1074 	const struct xfrm_selector *sel = &pol->selector;
1075 	int ret = -ESRCH;
1076 	bool match;
1077 
1078 	if (pol->family != family ||
1079 	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1080 	    pol->type != type)
1081 		return ret;
1082 
1083 	match = xfrm_selector_match(sel, fl, family);
1084 	if (match)
1085 		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1086 						  dir);
1087 
1088 	return ret;
1089 }
1090 
1091 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1092 						     const struct flowi *fl,
1093 						     u16 family, u8 dir)
1094 {
1095 	int err;
1096 	struct xfrm_policy *pol, *ret;
1097 	const xfrm_address_t *daddr, *saddr;
1098 	struct hlist_head *chain;
1099 	u32 priority = ~0U;
1100 
1101 	daddr = xfrm_flowi_daddr(fl, family);
1102 	saddr = xfrm_flowi_saddr(fl, family);
1103 	if (unlikely(!daddr || !saddr))
1104 		return NULL;
1105 
1106 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
1107 	chain = policy_hash_direct(net, daddr, saddr, family, dir);
1108 	ret = NULL;
1109 	hlist_for_each_entry(pol, chain, bydst) {
1110 		err = xfrm_policy_match(pol, fl, type, family, dir);
1111 		if (err) {
1112 			if (err == -ESRCH)
1113 				continue;
1114 			else {
1115 				ret = ERR_PTR(err);
1116 				goto fail;
1117 			}
1118 		} else {
1119 			ret = pol;
1120 			priority = ret->priority;
1121 			break;
1122 		}
1123 	}
1124 	chain = &net->xfrm.policy_inexact[dir];
1125 	hlist_for_each_entry(pol, chain, bydst) {
1126 		if ((pol->priority >= priority) && ret)
1127 			break;
1128 
1129 		err = xfrm_policy_match(pol, fl, type, family, dir);
1130 		if (err) {
1131 			if (err == -ESRCH)
1132 				continue;
1133 			else {
1134 				ret = ERR_PTR(err);
1135 				goto fail;
1136 			}
1137 		} else {
1138 			ret = pol;
1139 			break;
1140 		}
1141 	}
1142 
1143 	xfrm_pol_hold(ret);
1144 fail:
1145 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
1146 
1147 	return ret;
1148 }
1149 
1150 static struct xfrm_policy *
1151 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1152 {
1153 #ifdef CONFIG_XFRM_SUB_POLICY
1154 	struct xfrm_policy *pol;
1155 
1156 	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1157 	if (pol != NULL)
1158 		return pol;
1159 #endif
1160 	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1161 }
1162 
1163 static int flow_to_policy_dir(int dir)
1164 {
1165 	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1166 	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1167 	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
1168 		return dir;
1169 
1170 	switch (dir) {
1171 	default:
1172 	case FLOW_DIR_IN:
1173 		return XFRM_POLICY_IN;
1174 	case FLOW_DIR_OUT:
1175 		return XFRM_POLICY_OUT;
1176 	case FLOW_DIR_FWD:
1177 		return XFRM_POLICY_FWD;
1178 	}
1179 }
1180 
1181 static struct flow_cache_object *
1182 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1183 		   u8 dir, struct flow_cache_object *old_obj, void *ctx)
1184 {
1185 	struct xfrm_policy *pol;
1186 
1187 	if (old_obj)
1188 		xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1189 
1190 	pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
1191 	if (IS_ERR_OR_NULL(pol))
1192 		return ERR_CAST(pol);
1193 
1194 	/* Resolver returns two references:
1195 	 * one for cache and one for caller of flow_cache_lookup() */
1196 	xfrm_pol_hold(pol);
1197 
1198 	return &pol->flo;
1199 }
1200 
1201 static inline int policy_to_flow_dir(int dir)
1202 {
1203 	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1204 	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1205 	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
1206 		return dir;
1207 	switch (dir) {
1208 	default:
1209 	case XFRM_POLICY_IN:
1210 		return FLOW_DIR_IN;
1211 	case XFRM_POLICY_OUT:
1212 		return FLOW_DIR_OUT;
1213 	case XFRM_POLICY_FWD:
1214 		return FLOW_DIR_FWD;
1215 	}
1216 }
1217 
1218 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1219 						 const struct flowi *fl)
1220 {
1221 	struct xfrm_policy *pol;
1222 	struct net *net = sock_net(sk);
1223 
1224 	rcu_read_lock();
1225 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
1226 	pol = rcu_dereference(sk->sk_policy[dir]);
1227 	if (pol != NULL) {
1228 		bool match = xfrm_selector_match(&pol->selector, fl,
1229 						 sk->sk_family);
1230 		int err = 0;
1231 
1232 		if (match) {
1233 			if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1234 				pol = NULL;
1235 				goto out;
1236 			}
1237 			err = security_xfrm_policy_lookup(pol->security,
1238 						      fl->flowi_secid,
1239 						      policy_to_flow_dir(dir));
1240 			if (!err)
1241 				xfrm_pol_hold(pol);
1242 			else if (err == -ESRCH)
1243 				pol = NULL;
1244 			else
1245 				pol = ERR_PTR(err);
1246 		} else
1247 			pol = NULL;
1248 	}
1249 out:
1250 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
1251 	rcu_read_unlock();
1252 	return pol;
1253 }
1254 
1255 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1256 {
1257 	struct net *net = xp_net(pol);
1258 
1259 	list_add(&pol->walk.all, &net->xfrm.policy_all);
1260 	net->xfrm.policy_count[dir]++;
1261 	xfrm_pol_hold(pol);
1262 }
1263 
1264 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1265 						int dir)
1266 {
1267 	struct net *net = xp_net(pol);
1268 
1269 	if (list_empty(&pol->walk.all))
1270 		return NULL;
1271 
1272 	/* Socket policies are not hashed. */
1273 	if (!hlist_unhashed(&pol->bydst)) {
1274 		hlist_del(&pol->bydst);
1275 		hlist_del(&pol->byidx);
1276 	}
1277 
1278 	list_del_init(&pol->walk.all);
1279 	net->xfrm.policy_count[dir]--;
1280 
1281 	return pol;
1282 }
1283 
1284 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1285 {
1286 	__xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1287 }
1288 
1289 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1290 {
1291 	__xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1292 }
1293 
1294 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1295 {
1296 	struct net *net = xp_net(pol);
1297 
1298 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1299 	pol = __xfrm_policy_unlink(pol, dir);
1300 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1301 	if (pol) {
1302 		xfrm_policy_kill(pol);
1303 		return 0;
1304 	}
1305 	return -ENOENT;
1306 }
1307 EXPORT_SYMBOL(xfrm_policy_delete);
1308 
1309 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1310 {
1311 	struct net *net = xp_net(pol);
1312 	struct xfrm_policy *old_pol;
1313 
1314 #ifdef CONFIG_XFRM_SUB_POLICY
1315 	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1316 		return -EINVAL;
1317 #endif
1318 
1319 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1320 	old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1321 				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1322 	if (pol) {
1323 		pol->curlft.add_time = get_seconds();
1324 		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1325 		xfrm_sk_policy_link(pol, dir);
1326 	}
1327 	rcu_assign_pointer(sk->sk_policy[dir], pol);
1328 	if (old_pol) {
1329 		if (pol)
1330 			xfrm_policy_requeue(old_pol, pol);
1331 
1332 		/* Unlinking succeeds always. This is the only function
1333 		 * allowed to delete or replace socket policy.
1334 		 */
1335 		xfrm_sk_policy_unlink(old_pol, dir);
1336 	}
1337 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1338 
1339 	if (old_pol) {
1340 		xfrm_policy_kill(old_pol);
1341 	}
1342 	return 0;
1343 }
1344 
1345 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1346 {
1347 	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1348 	struct net *net = xp_net(old);
1349 
1350 	if (newp) {
1351 		newp->selector = old->selector;
1352 		if (security_xfrm_policy_clone(old->security,
1353 					       &newp->security)) {
1354 			kfree(newp);
1355 			return NULL;  /* ENOMEM */
1356 		}
1357 		newp->lft = old->lft;
1358 		newp->curlft = old->curlft;
1359 		newp->mark = old->mark;
1360 		newp->action = old->action;
1361 		newp->flags = old->flags;
1362 		newp->xfrm_nr = old->xfrm_nr;
1363 		newp->index = old->index;
1364 		newp->type = old->type;
1365 		memcpy(newp->xfrm_vec, old->xfrm_vec,
1366 		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1367 		write_lock_bh(&net->xfrm.xfrm_policy_lock);
1368 		xfrm_sk_policy_link(newp, dir);
1369 		write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1370 		xfrm_pol_put(newp);
1371 	}
1372 	return newp;
1373 }
1374 
1375 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1376 {
1377 	const struct xfrm_policy *p;
1378 	struct xfrm_policy *np;
1379 	int i, ret = 0;
1380 
1381 	rcu_read_lock();
1382 	for (i = 0; i < 2; i++) {
1383 		p = rcu_dereference(osk->sk_policy[i]);
1384 		if (p) {
1385 			np = clone_policy(p, i);
1386 			if (unlikely(!np)) {
1387 				ret = -ENOMEM;
1388 				break;
1389 			}
1390 			rcu_assign_pointer(sk->sk_policy[i], np);
1391 		}
1392 	}
1393 	rcu_read_unlock();
1394 	return ret;
1395 }
1396 
1397 static int
1398 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1399 	       xfrm_address_t *remote, unsigned short family)
1400 {
1401 	int err;
1402 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1403 
1404 	if (unlikely(afinfo == NULL))
1405 		return -EINVAL;
1406 	err = afinfo->get_saddr(net, oif, local, remote);
1407 	xfrm_policy_put_afinfo(afinfo);
1408 	return err;
1409 }
1410 
1411 /* Resolve list of templates for the flow, given policy. */
1412 
1413 static int
1414 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1415 		      struct xfrm_state **xfrm, unsigned short family)
1416 {
1417 	struct net *net = xp_net(policy);
1418 	int nx;
1419 	int i, error;
1420 	xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1421 	xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1422 	xfrm_address_t tmp;
1423 
1424 	for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1425 		struct xfrm_state *x;
1426 		xfrm_address_t *remote = daddr;
1427 		xfrm_address_t *local  = saddr;
1428 		struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1429 
1430 		if (tmpl->mode == XFRM_MODE_TUNNEL ||
1431 		    tmpl->mode == XFRM_MODE_BEET) {
1432 			remote = &tmpl->id.daddr;
1433 			local = &tmpl->saddr;
1434 			if (xfrm_addr_any(local, tmpl->encap_family)) {
1435 				error = xfrm_get_saddr(net, fl->flowi_oif,
1436 						       &tmp, remote,
1437 						       tmpl->encap_family);
1438 				if (error)
1439 					goto fail;
1440 				local = &tmp;
1441 			}
1442 		}
1443 
1444 		x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1445 
1446 		if (x && x->km.state == XFRM_STATE_VALID) {
1447 			xfrm[nx++] = x;
1448 			daddr = remote;
1449 			saddr = local;
1450 			continue;
1451 		}
1452 		if (x) {
1453 			error = (x->km.state == XFRM_STATE_ERROR ?
1454 				 -EINVAL : -EAGAIN);
1455 			xfrm_state_put(x);
1456 		} else if (error == -ESRCH) {
1457 			error = -EAGAIN;
1458 		}
1459 
1460 		if (!tmpl->optional)
1461 			goto fail;
1462 	}
1463 	return nx;
1464 
1465 fail:
1466 	for (nx--; nx >= 0; nx--)
1467 		xfrm_state_put(xfrm[nx]);
1468 	return error;
1469 }
1470 
1471 static int
1472 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1473 		  struct xfrm_state **xfrm, unsigned short family)
1474 {
1475 	struct xfrm_state *tp[XFRM_MAX_DEPTH];
1476 	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1477 	int cnx = 0;
1478 	int error;
1479 	int ret;
1480 	int i;
1481 
1482 	for (i = 0; i < npols; i++) {
1483 		if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1484 			error = -ENOBUFS;
1485 			goto fail;
1486 		}
1487 
1488 		ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1489 		if (ret < 0) {
1490 			error = ret;
1491 			goto fail;
1492 		} else
1493 			cnx += ret;
1494 	}
1495 
1496 	/* found states are sorted for outbound processing */
1497 	if (npols > 1)
1498 		xfrm_state_sort(xfrm, tpp, cnx, family);
1499 
1500 	return cnx;
1501 
1502  fail:
1503 	for (cnx--; cnx >= 0; cnx--)
1504 		xfrm_state_put(tpp[cnx]);
1505 	return error;
1506 
1507 }
1508 
1509 /* Check that the bundle accepts the flow and its components are
1510  * still valid.
1511  */
1512 
1513 static inline int xfrm_get_tos(const struct flowi *fl, int family)
1514 {
1515 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1516 	int tos;
1517 
1518 	if (!afinfo)
1519 		return -EINVAL;
1520 
1521 	tos = afinfo->get_tos(fl);
1522 
1523 	xfrm_policy_put_afinfo(afinfo);
1524 
1525 	return tos;
1526 }
1527 
1528 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1529 {
1530 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1531 	struct dst_entry *dst = &xdst->u.dst;
1532 
1533 	if (xdst->route == NULL) {
1534 		/* Dummy bundle - if it has xfrms we were not
1535 		 * able to build bundle as template resolution failed.
1536 		 * It means we need to try again resolving. */
1537 		if (xdst->num_xfrms > 0)
1538 			return NULL;
1539 	} else if (dst->flags & DST_XFRM_QUEUE) {
1540 		return NULL;
1541 	} else {
1542 		/* Real bundle */
1543 		if (stale_bundle(dst))
1544 			return NULL;
1545 	}
1546 
1547 	dst_hold(dst);
1548 	return flo;
1549 }
1550 
1551 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1552 {
1553 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1554 	struct dst_entry *dst = &xdst->u.dst;
1555 
1556 	if (!xdst->route)
1557 		return 0;
1558 	if (stale_bundle(dst))
1559 		return 0;
1560 
1561 	return 1;
1562 }
1563 
1564 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1565 {
1566 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1567 	struct dst_entry *dst = &xdst->u.dst;
1568 
1569 	dst_free(dst);
1570 }
1571 
1572 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1573 	.get = xfrm_bundle_flo_get,
1574 	.check = xfrm_bundle_flo_check,
1575 	.delete = xfrm_bundle_flo_delete,
1576 };
1577 
1578 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1579 {
1580 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1581 	struct dst_ops *dst_ops;
1582 	struct xfrm_dst *xdst;
1583 
1584 	if (!afinfo)
1585 		return ERR_PTR(-EINVAL);
1586 
1587 	switch (family) {
1588 	case AF_INET:
1589 		dst_ops = &net->xfrm.xfrm4_dst_ops;
1590 		break;
1591 #if IS_ENABLED(CONFIG_IPV6)
1592 	case AF_INET6:
1593 		dst_ops = &net->xfrm.xfrm6_dst_ops;
1594 		break;
1595 #endif
1596 	default:
1597 		BUG();
1598 	}
1599 	xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1600 
1601 	if (likely(xdst)) {
1602 		struct dst_entry *dst = &xdst->u.dst;
1603 
1604 		memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1605 		xdst->flo.ops = &xfrm_bundle_fc_ops;
1606 	} else
1607 		xdst = ERR_PTR(-ENOBUFS);
1608 
1609 	xfrm_policy_put_afinfo(afinfo);
1610 
1611 	return xdst;
1612 }
1613 
1614 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1615 				 int nfheader_len)
1616 {
1617 	struct xfrm_policy_afinfo *afinfo =
1618 		xfrm_policy_get_afinfo(dst->ops->family);
1619 	int err;
1620 
1621 	if (!afinfo)
1622 		return -EINVAL;
1623 
1624 	err = afinfo->init_path(path, dst, nfheader_len);
1625 
1626 	xfrm_policy_put_afinfo(afinfo);
1627 
1628 	return err;
1629 }
1630 
1631 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1632 				const struct flowi *fl)
1633 {
1634 	struct xfrm_policy_afinfo *afinfo =
1635 		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1636 	int err;
1637 
1638 	if (!afinfo)
1639 		return -EINVAL;
1640 
1641 	err = afinfo->fill_dst(xdst, dev, fl);
1642 
1643 	xfrm_policy_put_afinfo(afinfo);
1644 
1645 	return err;
1646 }
1647 
1648 
1649 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1650  * all the metrics... Shortly, bundle a bundle.
1651  */
1652 
1653 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1654 					    struct xfrm_state **xfrm, int nx,
1655 					    const struct flowi *fl,
1656 					    struct dst_entry *dst)
1657 {
1658 	struct net *net = xp_net(policy);
1659 	unsigned long now = jiffies;
1660 	struct net_device *dev;
1661 	struct xfrm_mode *inner_mode;
1662 	struct dst_entry *dst_prev = NULL;
1663 	struct dst_entry *dst0 = NULL;
1664 	int i = 0;
1665 	int err;
1666 	int header_len = 0;
1667 	int nfheader_len = 0;
1668 	int trailer_len = 0;
1669 	int tos;
1670 	int family = policy->selector.family;
1671 	xfrm_address_t saddr, daddr;
1672 
1673 	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1674 
1675 	tos = xfrm_get_tos(fl, family);
1676 	err = tos;
1677 	if (tos < 0)
1678 		goto put_states;
1679 
1680 	dst_hold(dst);
1681 
1682 	for (; i < nx; i++) {
1683 		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1684 		struct dst_entry *dst1 = &xdst->u.dst;
1685 
1686 		err = PTR_ERR(xdst);
1687 		if (IS_ERR(xdst)) {
1688 			dst_release(dst);
1689 			goto put_states;
1690 		}
1691 
1692 		if (xfrm[i]->sel.family == AF_UNSPEC) {
1693 			inner_mode = xfrm_ip2inner_mode(xfrm[i],
1694 							xfrm_af2proto(family));
1695 			if (!inner_mode) {
1696 				err = -EAFNOSUPPORT;
1697 				dst_release(dst);
1698 				goto put_states;
1699 			}
1700 		} else
1701 			inner_mode = xfrm[i]->inner_mode;
1702 
1703 		if (!dst_prev)
1704 			dst0 = dst1;
1705 		else {
1706 			dst_prev->child = dst_clone(dst1);
1707 			dst1->flags |= DST_NOHASH;
1708 		}
1709 
1710 		xdst->route = dst;
1711 		dst_copy_metrics(dst1, dst);
1712 
1713 		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1714 			family = xfrm[i]->props.family;
1715 			dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1716 					      &saddr, &daddr, family);
1717 			err = PTR_ERR(dst);
1718 			if (IS_ERR(dst))
1719 				goto put_states;
1720 		} else
1721 			dst_hold(dst);
1722 
1723 		dst1->xfrm = xfrm[i];
1724 		xdst->xfrm_genid = xfrm[i]->genid;
1725 
1726 		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1727 		dst1->flags |= DST_HOST;
1728 		dst1->lastuse = now;
1729 
1730 		dst1->input = dst_discard;
1731 		dst1->output = inner_mode->afinfo->output;
1732 
1733 		dst1->next = dst_prev;
1734 		dst_prev = dst1;
1735 
1736 		header_len += xfrm[i]->props.header_len;
1737 		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1738 			nfheader_len += xfrm[i]->props.header_len;
1739 		trailer_len += xfrm[i]->props.trailer_len;
1740 	}
1741 
1742 	dst_prev->child = dst;
1743 	dst0->path = dst;
1744 
1745 	err = -ENODEV;
1746 	dev = dst->dev;
1747 	if (!dev)
1748 		goto free_dst;
1749 
1750 	xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1751 	xfrm_init_pmtu(dst_prev);
1752 
1753 	for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1754 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1755 
1756 		err = xfrm_fill_dst(xdst, dev, fl);
1757 		if (err)
1758 			goto free_dst;
1759 
1760 		dst_prev->header_len = header_len;
1761 		dst_prev->trailer_len = trailer_len;
1762 		header_len -= xdst->u.dst.xfrm->props.header_len;
1763 		trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1764 	}
1765 
1766 out:
1767 	return dst0;
1768 
1769 put_states:
1770 	for (; i < nx; i++)
1771 		xfrm_state_put(xfrm[i]);
1772 free_dst:
1773 	if (dst0)
1774 		dst_free(dst0);
1775 	dst0 = ERR_PTR(err);
1776 	goto out;
1777 }
1778 
1779 #ifdef CONFIG_XFRM_SUB_POLICY
1780 static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
1781 {
1782 	if (!*target) {
1783 		*target = kmalloc(size, GFP_ATOMIC);
1784 		if (!*target)
1785 			return -ENOMEM;
1786 	}
1787 
1788 	memcpy(*target, src, size);
1789 	return 0;
1790 }
1791 #endif
1792 
1793 static int xfrm_dst_update_parent(struct dst_entry *dst,
1794 				  const struct xfrm_selector *sel)
1795 {
1796 #ifdef CONFIG_XFRM_SUB_POLICY
1797 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1798 	return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1799 				   sel, sizeof(*sel));
1800 #else
1801 	return 0;
1802 #endif
1803 }
1804 
1805 static int xfrm_dst_update_origin(struct dst_entry *dst,
1806 				  const struct flowi *fl)
1807 {
1808 #ifdef CONFIG_XFRM_SUB_POLICY
1809 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1810 	return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1811 #else
1812 	return 0;
1813 #endif
1814 }
1815 
1816 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1817 				struct xfrm_policy **pols,
1818 				int *num_pols, int *num_xfrms)
1819 {
1820 	int i;
1821 
1822 	if (*num_pols == 0 || !pols[0]) {
1823 		*num_pols = 0;
1824 		*num_xfrms = 0;
1825 		return 0;
1826 	}
1827 	if (IS_ERR(pols[0]))
1828 		return PTR_ERR(pols[0]);
1829 
1830 	*num_xfrms = pols[0]->xfrm_nr;
1831 
1832 #ifdef CONFIG_XFRM_SUB_POLICY
1833 	if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1834 	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1835 		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1836 						    XFRM_POLICY_TYPE_MAIN,
1837 						    fl, family,
1838 						    XFRM_POLICY_OUT);
1839 		if (pols[1]) {
1840 			if (IS_ERR(pols[1])) {
1841 				xfrm_pols_put(pols, *num_pols);
1842 				return PTR_ERR(pols[1]);
1843 			}
1844 			(*num_pols)++;
1845 			(*num_xfrms) += pols[1]->xfrm_nr;
1846 		}
1847 	}
1848 #endif
1849 	for (i = 0; i < *num_pols; i++) {
1850 		if (pols[i]->action != XFRM_POLICY_ALLOW) {
1851 			*num_xfrms = -1;
1852 			break;
1853 		}
1854 	}
1855 
1856 	return 0;
1857 
1858 }
1859 
1860 static struct xfrm_dst *
1861 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1862 			       const struct flowi *fl, u16 family,
1863 			       struct dst_entry *dst_orig)
1864 {
1865 	struct net *net = xp_net(pols[0]);
1866 	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1867 	struct dst_entry *dst;
1868 	struct xfrm_dst *xdst;
1869 	int err;
1870 
1871 	/* Try to instantiate a bundle */
1872 	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1873 	if (err <= 0) {
1874 		if (err != 0 && err != -EAGAIN)
1875 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1876 		return ERR_PTR(err);
1877 	}
1878 
1879 	dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1880 	if (IS_ERR(dst)) {
1881 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1882 		return ERR_CAST(dst);
1883 	}
1884 
1885 	xdst = (struct xfrm_dst *)dst;
1886 	xdst->num_xfrms = err;
1887 	if (num_pols > 1)
1888 		err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1889 	else
1890 		err = xfrm_dst_update_origin(dst, fl);
1891 	if (unlikely(err)) {
1892 		dst_free(dst);
1893 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1894 		return ERR_PTR(err);
1895 	}
1896 
1897 	xdst->num_pols = num_pols;
1898 	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1899 	xdst->policy_genid = atomic_read(&pols[0]->genid);
1900 
1901 	return xdst;
1902 }
1903 
1904 static void xfrm_policy_queue_process(unsigned long arg)
1905 {
1906 	struct sk_buff *skb;
1907 	struct sock *sk;
1908 	struct dst_entry *dst;
1909 	struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1910 	struct net *net = xp_net(pol);
1911 	struct xfrm_policy_queue *pq = &pol->polq;
1912 	struct flowi fl;
1913 	struct sk_buff_head list;
1914 
1915 	spin_lock(&pq->hold_queue.lock);
1916 	skb = skb_peek(&pq->hold_queue);
1917 	if (!skb) {
1918 		spin_unlock(&pq->hold_queue.lock);
1919 		goto out;
1920 	}
1921 	dst = skb_dst(skb);
1922 	sk = skb->sk;
1923 	xfrm_decode_session(skb, &fl, dst->ops->family);
1924 	spin_unlock(&pq->hold_queue.lock);
1925 
1926 	dst_hold(dst->path);
1927 	dst = xfrm_lookup(net, dst->path, &fl, sk, 0);
1928 	if (IS_ERR(dst))
1929 		goto purge_queue;
1930 
1931 	if (dst->flags & DST_XFRM_QUEUE) {
1932 		dst_release(dst);
1933 
1934 		if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1935 			goto purge_queue;
1936 
1937 		pq->timeout = pq->timeout << 1;
1938 		if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1939 			xfrm_pol_hold(pol);
1940 	goto out;
1941 	}
1942 
1943 	dst_release(dst);
1944 
1945 	__skb_queue_head_init(&list);
1946 
1947 	spin_lock(&pq->hold_queue.lock);
1948 	pq->timeout = 0;
1949 	skb_queue_splice_init(&pq->hold_queue, &list);
1950 	spin_unlock(&pq->hold_queue.lock);
1951 
1952 	while (!skb_queue_empty(&list)) {
1953 		skb = __skb_dequeue(&list);
1954 
1955 		xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1956 		dst_hold(skb_dst(skb)->path);
1957 		dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0);
1958 		if (IS_ERR(dst)) {
1959 			kfree_skb(skb);
1960 			continue;
1961 		}
1962 
1963 		nf_reset(skb);
1964 		skb_dst_drop(skb);
1965 		skb_dst_set(skb, dst);
1966 
1967 		dst_output(net, skb->sk, skb);
1968 	}
1969 
1970 out:
1971 	xfrm_pol_put(pol);
1972 	return;
1973 
1974 purge_queue:
1975 	pq->timeout = 0;
1976 	skb_queue_purge(&pq->hold_queue);
1977 	xfrm_pol_put(pol);
1978 }
1979 
1980 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1981 {
1982 	unsigned long sched_next;
1983 	struct dst_entry *dst = skb_dst(skb);
1984 	struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1985 	struct xfrm_policy *pol = xdst->pols[0];
1986 	struct xfrm_policy_queue *pq = &pol->polq;
1987 
1988 	if (unlikely(skb_fclone_busy(sk, skb))) {
1989 		kfree_skb(skb);
1990 		return 0;
1991 	}
1992 
1993 	if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1994 		kfree_skb(skb);
1995 		return -EAGAIN;
1996 	}
1997 
1998 	skb_dst_force(skb);
1999 
2000 	spin_lock_bh(&pq->hold_queue.lock);
2001 
2002 	if (!pq->timeout)
2003 		pq->timeout = XFRM_QUEUE_TMO_MIN;
2004 
2005 	sched_next = jiffies + pq->timeout;
2006 
2007 	if (del_timer(&pq->hold_timer)) {
2008 		if (time_before(pq->hold_timer.expires, sched_next))
2009 			sched_next = pq->hold_timer.expires;
2010 		xfrm_pol_put(pol);
2011 	}
2012 
2013 	__skb_queue_tail(&pq->hold_queue, skb);
2014 	if (!mod_timer(&pq->hold_timer, sched_next))
2015 		xfrm_pol_hold(pol);
2016 
2017 	spin_unlock_bh(&pq->hold_queue.lock);
2018 
2019 	return 0;
2020 }
2021 
2022 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2023 						 struct xfrm_flo *xflo,
2024 						 const struct flowi *fl,
2025 						 int num_xfrms,
2026 						 u16 family)
2027 {
2028 	int err;
2029 	struct net_device *dev;
2030 	struct dst_entry *dst;
2031 	struct dst_entry *dst1;
2032 	struct xfrm_dst *xdst;
2033 
2034 	xdst = xfrm_alloc_dst(net, family);
2035 	if (IS_ERR(xdst))
2036 		return xdst;
2037 
2038 	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2039 	    net->xfrm.sysctl_larval_drop ||
2040 	    num_xfrms <= 0)
2041 		return xdst;
2042 
2043 	dst = xflo->dst_orig;
2044 	dst1 = &xdst->u.dst;
2045 	dst_hold(dst);
2046 	xdst->route = dst;
2047 
2048 	dst_copy_metrics(dst1, dst);
2049 
2050 	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2051 	dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2052 	dst1->lastuse = jiffies;
2053 
2054 	dst1->input = dst_discard;
2055 	dst1->output = xdst_queue_output;
2056 
2057 	dst_hold(dst);
2058 	dst1->child = dst;
2059 	dst1->path = dst;
2060 
2061 	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2062 
2063 	err = -ENODEV;
2064 	dev = dst->dev;
2065 	if (!dev)
2066 		goto free_dst;
2067 
2068 	err = xfrm_fill_dst(xdst, dev, fl);
2069 	if (err)
2070 		goto free_dst;
2071 
2072 out:
2073 	return xdst;
2074 
2075 free_dst:
2076 	dst_release(dst1);
2077 	xdst = ERR_PTR(err);
2078 	goto out;
2079 }
2080 
2081 static struct flow_cache_object *
2082 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
2083 		   struct flow_cache_object *oldflo, void *ctx)
2084 {
2085 	struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
2086 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2087 	struct xfrm_dst *xdst, *new_xdst;
2088 	int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
2089 
2090 	/* Check if the policies from old bundle are usable */
2091 	xdst = NULL;
2092 	if (oldflo) {
2093 		xdst = container_of(oldflo, struct xfrm_dst, flo);
2094 		num_pols = xdst->num_pols;
2095 		num_xfrms = xdst->num_xfrms;
2096 		pol_dead = 0;
2097 		for (i = 0; i < num_pols; i++) {
2098 			pols[i] = xdst->pols[i];
2099 			pol_dead |= pols[i]->walk.dead;
2100 		}
2101 		if (pol_dead) {
2102 			dst_free(&xdst->u.dst);
2103 			xdst = NULL;
2104 			num_pols = 0;
2105 			num_xfrms = 0;
2106 			oldflo = NULL;
2107 		}
2108 	}
2109 
2110 	/* Resolve policies to use if we couldn't get them from
2111 	 * previous cache entry */
2112 	if (xdst == NULL) {
2113 		num_pols = 1;
2114 		pols[0] = __xfrm_policy_lookup(net, fl, family,
2115 					       flow_to_policy_dir(dir));
2116 		err = xfrm_expand_policies(fl, family, pols,
2117 					   &num_pols, &num_xfrms);
2118 		if (err < 0)
2119 			goto inc_error;
2120 		if (num_pols == 0)
2121 			return NULL;
2122 		if (num_xfrms <= 0)
2123 			goto make_dummy_bundle;
2124 	}
2125 
2126 	new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2127 						  xflo->dst_orig);
2128 	if (IS_ERR(new_xdst)) {
2129 		err = PTR_ERR(new_xdst);
2130 		if (err != -EAGAIN)
2131 			goto error;
2132 		if (oldflo == NULL)
2133 			goto make_dummy_bundle;
2134 		dst_hold(&xdst->u.dst);
2135 		return oldflo;
2136 	} else if (new_xdst == NULL) {
2137 		num_xfrms = 0;
2138 		if (oldflo == NULL)
2139 			goto make_dummy_bundle;
2140 		xdst->num_xfrms = 0;
2141 		dst_hold(&xdst->u.dst);
2142 		return oldflo;
2143 	}
2144 
2145 	/* Kill the previous bundle */
2146 	if (xdst) {
2147 		/* The policies were stolen for newly generated bundle */
2148 		xdst->num_pols = 0;
2149 		dst_free(&xdst->u.dst);
2150 	}
2151 
2152 	/* Flow cache does not have reference, it dst_free()'s,
2153 	 * but we do need to return one reference for original caller */
2154 	dst_hold(&new_xdst->u.dst);
2155 	return &new_xdst->flo;
2156 
2157 make_dummy_bundle:
2158 	/* We found policies, but there's no bundles to instantiate:
2159 	 * either because the policy blocks, has no transformations or
2160 	 * we could not build template (no xfrm_states).*/
2161 	xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2162 	if (IS_ERR(xdst)) {
2163 		xfrm_pols_put(pols, num_pols);
2164 		return ERR_CAST(xdst);
2165 	}
2166 	xdst->num_pols = num_pols;
2167 	xdst->num_xfrms = num_xfrms;
2168 	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2169 
2170 	dst_hold(&xdst->u.dst);
2171 	return &xdst->flo;
2172 
2173 inc_error:
2174 	XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2175 error:
2176 	if (xdst != NULL)
2177 		dst_free(&xdst->u.dst);
2178 	else
2179 		xfrm_pols_put(pols, num_pols);
2180 	return ERR_PTR(err);
2181 }
2182 
2183 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2184 					struct dst_entry *dst_orig)
2185 {
2186 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2187 	struct dst_entry *ret;
2188 
2189 	if (!afinfo) {
2190 		dst_release(dst_orig);
2191 		return ERR_PTR(-EINVAL);
2192 	} else {
2193 		ret = afinfo->blackhole_route(net, dst_orig);
2194 	}
2195 	xfrm_policy_put_afinfo(afinfo);
2196 
2197 	return ret;
2198 }
2199 
2200 /* Main function: finds/creates a bundle for given flow.
2201  *
2202  * At the moment we eat a raw IP route. Mostly to speed up lookups
2203  * on interfaces with disabled IPsec.
2204  */
2205 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2206 			      const struct flowi *fl,
2207 			      const struct sock *sk, int flags)
2208 {
2209 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2210 	struct flow_cache_object *flo;
2211 	struct xfrm_dst *xdst;
2212 	struct dst_entry *dst, *route;
2213 	u16 family = dst_orig->ops->family;
2214 	u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2215 	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2216 
2217 	dst = NULL;
2218 	xdst = NULL;
2219 	route = NULL;
2220 
2221 	sk = sk_const_to_full_sk(sk);
2222 	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2223 		num_pols = 1;
2224 		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2225 		err = xfrm_expand_policies(fl, family, pols,
2226 					   &num_pols, &num_xfrms);
2227 		if (err < 0)
2228 			goto dropdst;
2229 
2230 		if (num_pols) {
2231 			if (num_xfrms <= 0) {
2232 				drop_pols = num_pols;
2233 				goto no_transform;
2234 			}
2235 
2236 			xdst = xfrm_resolve_and_create_bundle(
2237 					pols, num_pols, fl,
2238 					family, dst_orig);
2239 			if (IS_ERR(xdst)) {
2240 				xfrm_pols_put(pols, num_pols);
2241 				err = PTR_ERR(xdst);
2242 				goto dropdst;
2243 			} else if (xdst == NULL) {
2244 				num_xfrms = 0;
2245 				drop_pols = num_pols;
2246 				goto no_transform;
2247 			}
2248 
2249 			dst_hold(&xdst->u.dst);
2250 			xdst->u.dst.flags |= DST_NOCACHE;
2251 			route = xdst->route;
2252 		}
2253 	}
2254 
2255 	if (xdst == NULL) {
2256 		struct xfrm_flo xflo;
2257 
2258 		xflo.dst_orig = dst_orig;
2259 		xflo.flags = flags;
2260 
2261 		/* To accelerate a bit...  */
2262 		if ((dst_orig->flags & DST_NOXFRM) ||
2263 		    !net->xfrm.policy_count[XFRM_POLICY_OUT])
2264 			goto nopol;
2265 
2266 		flo = flow_cache_lookup(net, fl, family, dir,
2267 					xfrm_bundle_lookup, &xflo);
2268 		if (flo == NULL)
2269 			goto nopol;
2270 		if (IS_ERR(flo)) {
2271 			err = PTR_ERR(flo);
2272 			goto dropdst;
2273 		}
2274 		xdst = container_of(flo, struct xfrm_dst, flo);
2275 
2276 		num_pols = xdst->num_pols;
2277 		num_xfrms = xdst->num_xfrms;
2278 		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2279 		route = xdst->route;
2280 	}
2281 
2282 	dst = &xdst->u.dst;
2283 	if (route == NULL && num_xfrms > 0) {
2284 		/* The only case when xfrm_bundle_lookup() returns a
2285 		 * bundle with null route, is when the template could
2286 		 * not be resolved. It means policies are there, but
2287 		 * bundle could not be created, since we don't yet
2288 		 * have the xfrm_state's. We need to wait for KM to
2289 		 * negotiate new SA's or bail out with error.*/
2290 		if (net->xfrm.sysctl_larval_drop) {
2291 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2292 			err = -EREMOTE;
2293 			goto error;
2294 		}
2295 
2296 		err = -EAGAIN;
2297 
2298 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2299 		goto error;
2300 	}
2301 
2302 no_transform:
2303 	if (num_pols == 0)
2304 		goto nopol;
2305 
2306 	if ((flags & XFRM_LOOKUP_ICMP) &&
2307 	    !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2308 		err = -ENOENT;
2309 		goto error;
2310 	}
2311 
2312 	for (i = 0; i < num_pols; i++)
2313 		pols[i]->curlft.use_time = get_seconds();
2314 
2315 	if (num_xfrms < 0) {
2316 		/* Prohibit the flow */
2317 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2318 		err = -EPERM;
2319 		goto error;
2320 	} else if (num_xfrms > 0) {
2321 		/* Flow transformed */
2322 		dst_release(dst_orig);
2323 	} else {
2324 		/* Flow passes untransformed */
2325 		dst_release(dst);
2326 		dst = dst_orig;
2327 	}
2328 ok:
2329 	xfrm_pols_put(pols, drop_pols);
2330 	if (dst && dst->xfrm &&
2331 	    dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2332 		dst->flags |= DST_XFRM_TUNNEL;
2333 	return dst;
2334 
2335 nopol:
2336 	if (!(flags & XFRM_LOOKUP_ICMP)) {
2337 		dst = dst_orig;
2338 		goto ok;
2339 	}
2340 	err = -ENOENT;
2341 error:
2342 	dst_release(dst);
2343 dropdst:
2344 	if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2345 		dst_release(dst_orig);
2346 	xfrm_pols_put(pols, drop_pols);
2347 	return ERR_PTR(err);
2348 }
2349 EXPORT_SYMBOL(xfrm_lookup);
2350 
2351 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2352  * Otherwise we may send out blackholed packets.
2353  */
2354 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2355 				    const struct flowi *fl,
2356 				    const struct sock *sk, int flags)
2357 {
2358 	struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2359 					    flags | XFRM_LOOKUP_QUEUE |
2360 					    XFRM_LOOKUP_KEEP_DST_REF);
2361 
2362 	if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2363 		return make_blackhole(net, dst_orig->ops->family, dst_orig);
2364 
2365 	return dst;
2366 }
2367 EXPORT_SYMBOL(xfrm_lookup_route);
2368 
2369 static inline int
2370 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2371 {
2372 	struct xfrm_state *x;
2373 
2374 	if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2375 		return 0;
2376 	x = skb->sp->xvec[idx];
2377 	if (!x->type->reject)
2378 		return 0;
2379 	return x->type->reject(x, skb, fl);
2380 }
2381 
2382 /* When skb is transformed back to its "native" form, we have to
2383  * check policy restrictions. At the moment we make this in maximally
2384  * stupid way. Shame on me. :-) Of course, connected sockets must
2385  * have policy cached at them.
2386  */
2387 
2388 static inline int
2389 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2390 	      unsigned short family)
2391 {
2392 	if (xfrm_state_kern(x))
2393 		return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2394 	return	x->id.proto == tmpl->id.proto &&
2395 		(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2396 		(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2397 		x->props.mode == tmpl->mode &&
2398 		(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2399 		 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2400 		!(x->props.mode != XFRM_MODE_TRANSPORT &&
2401 		  xfrm_state_addr_cmp(tmpl, x, family));
2402 }
2403 
2404 /*
2405  * 0 or more than 0 is returned when validation is succeeded (either bypass
2406  * because of optional transport mode, or next index of the mathced secpath
2407  * state with the template.
2408  * -1 is returned when no matching template is found.
2409  * Otherwise "-2 - errored_index" is returned.
2410  */
2411 static inline int
2412 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2413 	       unsigned short family)
2414 {
2415 	int idx = start;
2416 
2417 	if (tmpl->optional) {
2418 		if (tmpl->mode == XFRM_MODE_TRANSPORT)
2419 			return start;
2420 	} else
2421 		start = -1;
2422 	for (; idx < sp->len; idx++) {
2423 		if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2424 			return ++idx;
2425 		if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2426 			if (start == -1)
2427 				start = -2-idx;
2428 			break;
2429 		}
2430 	}
2431 	return start;
2432 }
2433 
2434 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2435 			  unsigned int family, int reverse)
2436 {
2437 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2438 	int err;
2439 
2440 	if (unlikely(afinfo == NULL))
2441 		return -EAFNOSUPPORT;
2442 
2443 	afinfo->decode_session(skb, fl, reverse);
2444 	err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2445 	xfrm_policy_put_afinfo(afinfo);
2446 	return err;
2447 }
2448 EXPORT_SYMBOL(__xfrm_decode_session);
2449 
2450 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2451 {
2452 	for (; k < sp->len; k++) {
2453 		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2454 			*idxp = k;
2455 			return 1;
2456 		}
2457 	}
2458 
2459 	return 0;
2460 }
2461 
2462 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2463 			unsigned short family)
2464 {
2465 	struct net *net = dev_net(skb->dev);
2466 	struct xfrm_policy *pol;
2467 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2468 	int npols = 0;
2469 	int xfrm_nr;
2470 	int pi;
2471 	int reverse;
2472 	struct flowi fl;
2473 	u8 fl_dir;
2474 	int xerr_idx = -1;
2475 
2476 	reverse = dir & ~XFRM_POLICY_MASK;
2477 	dir &= XFRM_POLICY_MASK;
2478 	fl_dir = policy_to_flow_dir(dir);
2479 
2480 	if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2481 		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2482 		return 0;
2483 	}
2484 
2485 	nf_nat_decode_session(skb, &fl, family);
2486 
2487 	/* First, check used SA against their selectors. */
2488 	if (skb->sp) {
2489 		int i;
2490 
2491 		for (i = skb->sp->len-1; i >= 0; i--) {
2492 			struct xfrm_state *x = skb->sp->xvec[i];
2493 			if (!xfrm_selector_match(&x->sel, &fl, family)) {
2494 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2495 				return 0;
2496 			}
2497 		}
2498 	}
2499 
2500 	pol = NULL;
2501 	sk = sk_to_full_sk(sk);
2502 	if (sk && sk->sk_policy[dir]) {
2503 		pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2504 		if (IS_ERR(pol)) {
2505 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2506 			return 0;
2507 		}
2508 	}
2509 
2510 	if (!pol) {
2511 		struct flow_cache_object *flo;
2512 
2513 		flo = flow_cache_lookup(net, &fl, family, fl_dir,
2514 					xfrm_policy_lookup, NULL);
2515 		if (IS_ERR_OR_NULL(flo))
2516 			pol = ERR_CAST(flo);
2517 		else
2518 			pol = container_of(flo, struct xfrm_policy, flo);
2519 	}
2520 
2521 	if (IS_ERR(pol)) {
2522 		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2523 		return 0;
2524 	}
2525 
2526 	if (!pol) {
2527 		if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2528 			xfrm_secpath_reject(xerr_idx, skb, &fl);
2529 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2530 			return 0;
2531 		}
2532 		return 1;
2533 	}
2534 
2535 	pol->curlft.use_time = get_seconds();
2536 
2537 	pols[0] = pol;
2538 	npols++;
2539 #ifdef CONFIG_XFRM_SUB_POLICY
2540 	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2541 		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2542 						    &fl, family,
2543 						    XFRM_POLICY_IN);
2544 		if (pols[1]) {
2545 			if (IS_ERR(pols[1])) {
2546 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2547 				return 0;
2548 			}
2549 			pols[1]->curlft.use_time = get_seconds();
2550 			npols++;
2551 		}
2552 	}
2553 #endif
2554 
2555 	if (pol->action == XFRM_POLICY_ALLOW) {
2556 		struct sec_path *sp;
2557 		static struct sec_path dummy;
2558 		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2559 		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2560 		struct xfrm_tmpl **tpp = tp;
2561 		int ti = 0;
2562 		int i, k;
2563 
2564 		if ((sp = skb->sp) == NULL)
2565 			sp = &dummy;
2566 
2567 		for (pi = 0; pi < npols; pi++) {
2568 			if (pols[pi] != pol &&
2569 			    pols[pi]->action != XFRM_POLICY_ALLOW) {
2570 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2571 				goto reject;
2572 			}
2573 			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2574 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2575 				goto reject_error;
2576 			}
2577 			for (i = 0; i < pols[pi]->xfrm_nr; i++)
2578 				tpp[ti++] = &pols[pi]->xfrm_vec[i];
2579 		}
2580 		xfrm_nr = ti;
2581 		if (npols > 1) {
2582 			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2583 			tpp = stp;
2584 		}
2585 
2586 		/* For each tunnel xfrm, find the first matching tmpl.
2587 		 * For each tmpl before that, find corresponding xfrm.
2588 		 * Order is _important_. Later we will implement
2589 		 * some barriers, but at the moment barriers
2590 		 * are implied between each two transformations.
2591 		 */
2592 		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2593 			k = xfrm_policy_ok(tpp[i], sp, k, family);
2594 			if (k < 0) {
2595 				if (k < -1)
2596 					/* "-2 - errored_index" returned */
2597 					xerr_idx = -(2+k);
2598 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2599 				goto reject;
2600 			}
2601 		}
2602 
2603 		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2604 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2605 			goto reject;
2606 		}
2607 
2608 		xfrm_pols_put(pols, npols);
2609 		return 1;
2610 	}
2611 	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2612 
2613 reject:
2614 	xfrm_secpath_reject(xerr_idx, skb, &fl);
2615 reject_error:
2616 	xfrm_pols_put(pols, npols);
2617 	return 0;
2618 }
2619 EXPORT_SYMBOL(__xfrm_policy_check);
2620 
2621 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2622 {
2623 	struct net *net = dev_net(skb->dev);
2624 	struct flowi fl;
2625 	struct dst_entry *dst;
2626 	int res = 1;
2627 
2628 	if (xfrm_decode_session(skb, &fl, family) < 0) {
2629 		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2630 		return 0;
2631 	}
2632 
2633 	skb_dst_force(skb);
2634 
2635 	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2636 	if (IS_ERR(dst)) {
2637 		res = 0;
2638 		dst = NULL;
2639 	}
2640 	skb_dst_set(skb, dst);
2641 	return res;
2642 }
2643 EXPORT_SYMBOL(__xfrm_route_forward);
2644 
2645 /* Optimize later using cookies and generation ids. */
2646 
2647 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2648 {
2649 	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2650 	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2651 	 * get validated by dst_ops->check on every use.  We do this
2652 	 * because when a normal route referenced by an XFRM dst is
2653 	 * obsoleted we do not go looking around for all parent
2654 	 * referencing XFRM dsts so that we can invalidate them.  It
2655 	 * is just too much work.  Instead we make the checks here on
2656 	 * every use.  For example:
2657 	 *
2658 	 *	XFRM dst A --> IPv4 dst X
2659 	 *
2660 	 * X is the "xdst->route" of A (X is also the "dst->path" of A
2661 	 * in this example).  If X is marked obsolete, "A" will not
2662 	 * notice.  That's what we are validating here via the
2663 	 * stale_bundle() check.
2664 	 *
2665 	 * When a policy's bundle is pruned, we dst_free() the XFRM
2666 	 * dst which causes it's ->obsolete field to be set to
2667 	 * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2668 	 * this, we want to force a new route lookup.
2669 	 */
2670 	if (dst->obsolete < 0 && !stale_bundle(dst))
2671 		return dst;
2672 
2673 	return NULL;
2674 }
2675 
2676 static int stale_bundle(struct dst_entry *dst)
2677 {
2678 	return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2679 }
2680 
2681 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2682 {
2683 	while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2684 		dst->dev = dev_net(dev)->loopback_dev;
2685 		dev_hold(dst->dev);
2686 		dev_put(dev);
2687 	}
2688 }
2689 EXPORT_SYMBOL(xfrm_dst_ifdown);
2690 
2691 static void xfrm_link_failure(struct sk_buff *skb)
2692 {
2693 	/* Impossible. Such dst must be popped before reaches point of failure. */
2694 }
2695 
2696 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2697 {
2698 	if (dst) {
2699 		if (dst->obsolete) {
2700 			dst_release(dst);
2701 			dst = NULL;
2702 		}
2703 	}
2704 	return dst;
2705 }
2706 
2707 void xfrm_garbage_collect(struct net *net)
2708 {
2709 	flow_cache_flush(net);
2710 }
2711 EXPORT_SYMBOL(xfrm_garbage_collect);
2712 
2713 static void xfrm_garbage_collect_deferred(struct net *net)
2714 {
2715 	flow_cache_flush_deferred(net);
2716 }
2717 
2718 static void xfrm_init_pmtu(struct dst_entry *dst)
2719 {
2720 	do {
2721 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2722 		u32 pmtu, route_mtu_cached;
2723 
2724 		pmtu = dst_mtu(dst->child);
2725 		xdst->child_mtu_cached = pmtu;
2726 
2727 		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2728 
2729 		route_mtu_cached = dst_mtu(xdst->route);
2730 		xdst->route_mtu_cached = route_mtu_cached;
2731 
2732 		if (pmtu > route_mtu_cached)
2733 			pmtu = route_mtu_cached;
2734 
2735 		dst_metric_set(dst, RTAX_MTU, pmtu);
2736 	} while ((dst = dst->next));
2737 }
2738 
2739 /* Check that the bundle accepts the flow and its components are
2740  * still valid.
2741  */
2742 
2743 static int xfrm_bundle_ok(struct xfrm_dst *first)
2744 {
2745 	struct dst_entry *dst = &first->u.dst;
2746 	struct xfrm_dst *last;
2747 	u32 mtu;
2748 
2749 	if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2750 	    (dst->dev && !netif_running(dst->dev)))
2751 		return 0;
2752 
2753 	if (dst->flags & DST_XFRM_QUEUE)
2754 		return 1;
2755 
2756 	last = NULL;
2757 
2758 	do {
2759 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2760 
2761 		if (dst->xfrm->km.state != XFRM_STATE_VALID)
2762 			return 0;
2763 		if (xdst->xfrm_genid != dst->xfrm->genid)
2764 			return 0;
2765 		if (xdst->num_pols > 0 &&
2766 		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2767 			return 0;
2768 
2769 		mtu = dst_mtu(dst->child);
2770 		if (xdst->child_mtu_cached != mtu) {
2771 			last = xdst;
2772 			xdst->child_mtu_cached = mtu;
2773 		}
2774 
2775 		if (!dst_check(xdst->route, xdst->route_cookie))
2776 			return 0;
2777 		mtu = dst_mtu(xdst->route);
2778 		if (xdst->route_mtu_cached != mtu) {
2779 			last = xdst;
2780 			xdst->route_mtu_cached = mtu;
2781 		}
2782 
2783 		dst = dst->child;
2784 	} while (dst->xfrm);
2785 
2786 	if (likely(!last))
2787 		return 1;
2788 
2789 	mtu = last->child_mtu_cached;
2790 	for (;;) {
2791 		dst = &last->u.dst;
2792 
2793 		mtu = xfrm_state_mtu(dst->xfrm, mtu);
2794 		if (mtu > last->route_mtu_cached)
2795 			mtu = last->route_mtu_cached;
2796 		dst_metric_set(dst, RTAX_MTU, mtu);
2797 
2798 		if (last == first)
2799 			break;
2800 
2801 		last = (struct xfrm_dst *)last->u.dst.next;
2802 		last->child_mtu_cached = mtu;
2803 	}
2804 
2805 	return 1;
2806 }
2807 
2808 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2809 {
2810 	return dst_metric_advmss(dst->path);
2811 }
2812 
2813 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2814 {
2815 	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2816 
2817 	return mtu ? : dst_mtu(dst->path);
2818 }
2819 
2820 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2821 					   struct sk_buff *skb,
2822 					   const void *daddr)
2823 {
2824 	return dst->path->ops->neigh_lookup(dst, skb, daddr);
2825 }
2826 
2827 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2828 {
2829 	int err = 0;
2830 	if (unlikely(afinfo == NULL))
2831 		return -EINVAL;
2832 	if (unlikely(afinfo->family >= NPROTO))
2833 		return -EAFNOSUPPORT;
2834 	spin_lock(&xfrm_policy_afinfo_lock);
2835 	if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2836 		err = -EEXIST;
2837 	else {
2838 		struct dst_ops *dst_ops = afinfo->dst_ops;
2839 		if (likely(dst_ops->kmem_cachep == NULL))
2840 			dst_ops->kmem_cachep = xfrm_dst_cache;
2841 		if (likely(dst_ops->check == NULL))
2842 			dst_ops->check = xfrm_dst_check;
2843 		if (likely(dst_ops->default_advmss == NULL))
2844 			dst_ops->default_advmss = xfrm_default_advmss;
2845 		if (likely(dst_ops->mtu == NULL))
2846 			dst_ops->mtu = xfrm_mtu;
2847 		if (likely(dst_ops->negative_advice == NULL))
2848 			dst_ops->negative_advice = xfrm_negative_advice;
2849 		if (likely(dst_ops->link_failure == NULL))
2850 			dst_ops->link_failure = xfrm_link_failure;
2851 		if (likely(dst_ops->neigh_lookup == NULL))
2852 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
2853 		if (likely(afinfo->garbage_collect == NULL))
2854 			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2855 		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
2856 	}
2857 	spin_unlock(&xfrm_policy_afinfo_lock);
2858 
2859 	return err;
2860 }
2861 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2862 
2863 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2864 {
2865 	int err = 0;
2866 	if (unlikely(afinfo == NULL))
2867 		return -EINVAL;
2868 	if (unlikely(afinfo->family >= NPROTO))
2869 		return -EAFNOSUPPORT;
2870 	spin_lock(&xfrm_policy_afinfo_lock);
2871 	if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2872 		if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2873 			err = -EINVAL;
2874 		else
2875 			RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
2876 					 NULL);
2877 	}
2878 	spin_unlock(&xfrm_policy_afinfo_lock);
2879 	if (!err) {
2880 		struct dst_ops *dst_ops = afinfo->dst_ops;
2881 
2882 		synchronize_rcu();
2883 
2884 		dst_ops->kmem_cachep = NULL;
2885 		dst_ops->check = NULL;
2886 		dst_ops->negative_advice = NULL;
2887 		dst_ops->link_failure = NULL;
2888 		afinfo->garbage_collect = NULL;
2889 	}
2890 	return err;
2891 }
2892 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2893 
2894 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2895 {
2896 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2897 
2898 	switch (event) {
2899 	case NETDEV_DOWN:
2900 		xfrm_garbage_collect(dev_net(dev));
2901 	}
2902 	return NOTIFY_DONE;
2903 }
2904 
2905 static struct notifier_block xfrm_dev_notifier = {
2906 	.notifier_call	= xfrm_dev_event,
2907 };
2908 
2909 #ifdef CONFIG_XFRM_STATISTICS
2910 static int __net_init xfrm_statistics_init(struct net *net)
2911 {
2912 	int rv;
2913 	net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2914 	if (!net->mib.xfrm_statistics)
2915 		return -ENOMEM;
2916 	rv = xfrm_proc_init(net);
2917 	if (rv < 0)
2918 		free_percpu(net->mib.xfrm_statistics);
2919 	return rv;
2920 }
2921 
2922 static void xfrm_statistics_fini(struct net *net)
2923 {
2924 	xfrm_proc_fini(net);
2925 	free_percpu(net->mib.xfrm_statistics);
2926 }
2927 #else
2928 static int __net_init xfrm_statistics_init(struct net *net)
2929 {
2930 	return 0;
2931 }
2932 
2933 static void xfrm_statistics_fini(struct net *net)
2934 {
2935 }
2936 #endif
2937 
2938 static int __net_init xfrm_policy_init(struct net *net)
2939 {
2940 	unsigned int hmask, sz;
2941 	int dir;
2942 
2943 	if (net_eq(net, &init_net))
2944 		xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2945 					   sizeof(struct xfrm_dst),
2946 					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2947 					   NULL);
2948 
2949 	hmask = 8 - 1;
2950 	sz = (hmask+1) * sizeof(struct hlist_head);
2951 
2952 	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2953 	if (!net->xfrm.policy_byidx)
2954 		goto out_byidx;
2955 	net->xfrm.policy_idx_hmask = hmask;
2956 
2957 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2958 		struct xfrm_policy_hash *htab;
2959 
2960 		net->xfrm.policy_count[dir] = 0;
2961 		net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2962 		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2963 
2964 		htab = &net->xfrm.policy_bydst[dir];
2965 		htab->table = xfrm_hash_alloc(sz);
2966 		if (!htab->table)
2967 			goto out_bydst;
2968 		htab->hmask = hmask;
2969 		htab->dbits4 = 32;
2970 		htab->sbits4 = 32;
2971 		htab->dbits6 = 128;
2972 		htab->sbits6 = 128;
2973 	}
2974 	net->xfrm.policy_hthresh.lbits4 = 32;
2975 	net->xfrm.policy_hthresh.rbits4 = 32;
2976 	net->xfrm.policy_hthresh.lbits6 = 128;
2977 	net->xfrm.policy_hthresh.rbits6 = 128;
2978 
2979 	seqlock_init(&net->xfrm.policy_hthresh.lock);
2980 
2981 	INIT_LIST_HEAD(&net->xfrm.policy_all);
2982 	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2983 	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2984 	if (net_eq(net, &init_net))
2985 		register_netdevice_notifier(&xfrm_dev_notifier);
2986 	return 0;
2987 
2988 out_bydst:
2989 	for (dir--; dir >= 0; dir--) {
2990 		struct xfrm_policy_hash *htab;
2991 
2992 		htab = &net->xfrm.policy_bydst[dir];
2993 		xfrm_hash_free(htab->table, sz);
2994 	}
2995 	xfrm_hash_free(net->xfrm.policy_byidx, sz);
2996 out_byidx:
2997 	return -ENOMEM;
2998 }
2999 
3000 static void xfrm_policy_fini(struct net *net)
3001 {
3002 	unsigned int sz;
3003 	int dir;
3004 
3005 	flush_work(&net->xfrm.policy_hash_work);
3006 #ifdef CONFIG_XFRM_SUB_POLICY
3007 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
3008 #endif
3009 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
3010 
3011 	WARN_ON(!list_empty(&net->xfrm.policy_all));
3012 
3013 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
3014 		struct xfrm_policy_hash *htab;
3015 
3016 		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
3017 
3018 		htab = &net->xfrm.policy_bydst[dir];
3019 		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
3020 		WARN_ON(!hlist_empty(htab->table));
3021 		xfrm_hash_free(htab->table, sz);
3022 	}
3023 
3024 	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
3025 	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
3026 	xfrm_hash_free(net->xfrm.policy_byidx, sz);
3027 }
3028 
3029 static int __net_init xfrm_net_init(struct net *net)
3030 {
3031 	int rv;
3032 
3033 	rv = xfrm_statistics_init(net);
3034 	if (rv < 0)
3035 		goto out_statistics;
3036 	rv = xfrm_state_init(net);
3037 	if (rv < 0)
3038 		goto out_state;
3039 	rv = xfrm_policy_init(net);
3040 	if (rv < 0)
3041 		goto out_policy;
3042 	rv = xfrm_sysctl_init(net);
3043 	if (rv < 0)
3044 		goto out_sysctl;
3045 	rv = flow_cache_init(net);
3046 	if (rv < 0)
3047 		goto out;
3048 
3049 	/* Initialize the per-net locks here */
3050 	spin_lock_init(&net->xfrm.xfrm_state_lock);
3051 	rwlock_init(&net->xfrm.xfrm_policy_lock);
3052 	mutex_init(&net->xfrm.xfrm_cfg_mutex);
3053 
3054 	return 0;
3055 
3056 out:
3057 	xfrm_sysctl_fini(net);
3058 out_sysctl:
3059 	xfrm_policy_fini(net);
3060 out_policy:
3061 	xfrm_state_fini(net);
3062 out_state:
3063 	xfrm_statistics_fini(net);
3064 out_statistics:
3065 	return rv;
3066 }
3067 
3068 static void __net_exit xfrm_net_exit(struct net *net)
3069 {
3070 	flow_cache_fini(net);
3071 	xfrm_sysctl_fini(net);
3072 	xfrm_policy_fini(net);
3073 	xfrm_state_fini(net);
3074 	xfrm_statistics_fini(net);
3075 }
3076 
3077 static struct pernet_operations __net_initdata xfrm_net_ops = {
3078 	.init = xfrm_net_init,
3079 	.exit = xfrm_net_exit,
3080 };
3081 
3082 void __init xfrm_init(void)
3083 {
3084 	register_pernet_subsys(&xfrm_net_ops);
3085 	xfrm_input_init();
3086 }
3087 
3088 #ifdef CONFIG_AUDITSYSCALL
3089 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3090 					 struct audit_buffer *audit_buf)
3091 {
3092 	struct xfrm_sec_ctx *ctx = xp->security;
3093 	struct xfrm_selector *sel = &xp->selector;
3094 
3095 	if (ctx)
3096 		audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3097 				 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3098 
3099 	switch (sel->family) {
3100 	case AF_INET:
3101 		audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3102 		if (sel->prefixlen_s != 32)
3103 			audit_log_format(audit_buf, " src_prefixlen=%d",
3104 					 sel->prefixlen_s);
3105 		audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3106 		if (sel->prefixlen_d != 32)
3107 			audit_log_format(audit_buf, " dst_prefixlen=%d",
3108 					 sel->prefixlen_d);
3109 		break;
3110 	case AF_INET6:
3111 		audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3112 		if (sel->prefixlen_s != 128)
3113 			audit_log_format(audit_buf, " src_prefixlen=%d",
3114 					 sel->prefixlen_s);
3115 		audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3116 		if (sel->prefixlen_d != 128)
3117 			audit_log_format(audit_buf, " dst_prefixlen=%d",
3118 					 sel->prefixlen_d);
3119 		break;
3120 	}
3121 }
3122 
3123 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3124 {
3125 	struct audit_buffer *audit_buf;
3126 
3127 	audit_buf = xfrm_audit_start("SPD-add");
3128 	if (audit_buf == NULL)
3129 		return;
3130 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3131 	audit_log_format(audit_buf, " res=%u", result);
3132 	xfrm_audit_common_policyinfo(xp, audit_buf);
3133 	audit_log_end(audit_buf);
3134 }
3135 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3136 
3137 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3138 			      bool task_valid)
3139 {
3140 	struct audit_buffer *audit_buf;
3141 
3142 	audit_buf = xfrm_audit_start("SPD-delete");
3143 	if (audit_buf == NULL)
3144 		return;
3145 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3146 	audit_log_format(audit_buf, " res=%u", result);
3147 	xfrm_audit_common_policyinfo(xp, audit_buf);
3148 	audit_log_end(audit_buf);
3149 }
3150 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3151 #endif
3152 
3153 #ifdef CONFIG_XFRM_MIGRATE
3154 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3155 					const struct xfrm_selector *sel_tgt)
3156 {
3157 	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3158 		if (sel_tgt->family == sel_cmp->family &&
3159 		    xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3160 				    sel_cmp->family) &&
3161 		    xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3162 				    sel_cmp->family) &&
3163 		    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3164 		    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3165 			return true;
3166 		}
3167 	} else {
3168 		if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3169 			return true;
3170 		}
3171 	}
3172 	return false;
3173 }
3174 
3175 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3176 						    u8 dir, u8 type, struct net *net)
3177 {
3178 	struct xfrm_policy *pol, *ret = NULL;
3179 	struct hlist_head *chain;
3180 	u32 priority = ~0U;
3181 
3182 	read_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME*/
3183 	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3184 	hlist_for_each_entry(pol, chain, bydst) {
3185 		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3186 		    pol->type == type) {
3187 			ret = pol;
3188 			priority = ret->priority;
3189 			break;
3190 		}
3191 	}
3192 	chain = &net->xfrm.policy_inexact[dir];
3193 	hlist_for_each_entry(pol, chain, bydst) {
3194 		if ((pol->priority >= priority) && ret)
3195 			break;
3196 
3197 		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3198 		    pol->type == type) {
3199 			ret = pol;
3200 			break;
3201 		}
3202 	}
3203 
3204 	xfrm_pol_hold(ret);
3205 
3206 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
3207 
3208 	return ret;
3209 }
3210 
3211 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3212 {
3213 	int match = 0;
3214 
3215 	if (t->mode == m->mode && t->id.proto == m->proto &&
3216 	    (m->reqid == 0 || t->reqid == m->reqid)) {
3217 		switch (t->mode) {
3218 		case XFRM_MODE_TUNNEL:
3219 		case XFRM_MODE_BEET:
3220 			if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3221 					    m->old_family) &&
3222 			    xfrm_addr_equal(&t->saddr, &m->old_saddr,
3223 					    m->old_family)) {
3224 				match = 1;
3225 			}
3226 			break;
3227 		case XFRM_MODE_TRANSPORT:
3228 			/* in case of transport mode, template does not store
3229 			   any IP addresses, hence we just compare mode and
3230 			   protocol */
3231 			match = 1;
3232 			break;
3233 		default:
3234 			break;
3235 		}
3236 	}
3237 	return match;
3238 }
3239 
3240 /* update endpoint address(es) of template(s) */
3241 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3242 			       struct xfrm_migrate *m, int num_migrate)
3243 {
3244 	struct xfrm_migrate *mp;
3245 	int i, j, n = 0;
3246 
3247 	write_lock_bh(&pol->lock);
3248 	if (unlikely(pol->walk.dead)) {
3249 		/* target policy has been deleted */
3250 		write_unlock_bh(&pol->lock);
3251 		return -ENOENT;
3252 	}
3253 
3254 	for (i = 0; i < pol->xfrm_nr; i++) {
3255 		for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3256 			if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3257 				continue;
3258 			n++;
3259 			if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3260 			    pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3261 				continue;
3262 			/* update endpoints */
3263 			memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3264 			       sizeof(pol->xfrm_vec[i].id.daddr));
3265 			memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3266 			       sizeof(pol->xfrm_vec[i].saddr));
3267 			pol->xfrm_vec[i].encap_family = mp->new_family;
3268 			/* flush bundles */
3269 			atomic_inc(&pol->genid);
3270 		}
3271 	}
3272 
3273 	write_unlock_bh(&pol->lock);
3274 
3275 	if (!n)
3276 		return -ENODATA;
3277 
3278 	return 0;
3279 }
3280 
3281 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3282 {
3283 	int i, j;
3284 
3285 	if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3286 		return -EINVAL;
3287 
3288 	for (i = 0; i < num_migrate; i++) {
3289 		if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3290 				    m[i].old_family) &&
3291 		    xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3292 				    m[i].old_family))
3293 			return -EINVAL;
3294 		if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3295 		    xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3296 			return -EINVAL;
3297 
3298 		/* check if there is any duplicated entry */
3299 		for (j = i + 1; j < num_migrate; j++) {
3300 			if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3301 				    sizeof(m[i].old_daddr)) &&
3302 			    !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3303 				    sizeof(m[i].old_saddr)) &&
3304 			    m[i].proto == m[j].proto &&
3305 			    m[i].mode == m[j].mode &&
3306 			    m[i].reqid == m[j].reqid &&
3307 			    m[i].old_family == m[j].old_family)
3308 				return -EINVAL;
3309 		}
3310 	}
3311 
3312 	return 0;
3313 }
3314 
3315 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3316 		 struct xfrm_migrate *m, int num_migrate,
3317 		 struct xfrm_kmaddress *k, struct net *net)
3318 {
3319 	int i, err, nx_cur = 0, nx_new = 0;
3320 	struct xfrm_policy *pol = NULL;
3321 	struct xfrm_state *x, *xc;
3322 	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3323 	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3324 	struct xfrm_migrate *mp;
3325 
3326 	if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3327 		goto out;
3328 
3329 	/* Stage 1 - find policy */
3330 	if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3331 		err = -ENOENT;
3332 		goto out;
3333 	}
3334 
3335 	/* Stage 2 - find and update state(s) */
3336 	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3337 		if ((x = xfrm_migrate_state_find(mp, net))) {
3338 			x_cur[nx_cur] = x;
3339 			nx_cur++;
3340 			if ((xc = xfrm_state_migrate(x, mp))) {
3341 				x_new[nx_new] = xc;
3342 				nx_new++;
3343 			} else {
3344 				err = -ENODATA;
3345 				goto restore_state;
3346 			}
3347 		}
3348 	}
3349 
3350 	/* Stage 3 - update policy */
3351 	if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3352 		goto restore_state;
3353 
3354 	/* Stage 4 - delete old state(s) */
3355 	if (nx_cur) {
3356 		xfrm_states_put(x_cur, nx_cur);
3357 		xfrm_states_delete(x_cur, nx_cur);
3358 	}
3359 
3360 	/* Stage 5 - announce */
3361 	km_migrate(sel, dir, type, m, num_migrate, k);
3362 
3363 	xfrm_pol_put(pol);
3364 
3365 	return 0;
3366 out:
3367 	return err;
3368 
3369 restore_state:
3370 	if (pol)
3371 		xfrm_pol_put(pol);
3372 	if (nx_cur)
3373 		xfrm_states_put(x_cur, nx_cur);
3374 	if (nx_new)
3375 		xfrm_states_delete(x_new, nx_new);
3376 
3377 	return err;
3378 }
3379 EXPORT_SYMBOL(xfrm_migrate);
3380 #endif
3381