xref: /openbmc/linux/net/xfrm/xfrm_policy.c (revision 95acd4c7)
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 struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
59 						int dir);
60 
61 static inline bool
62 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
63 {
64 	const struct flowi4 *fl4 = &fl->u.ip4;
65 
66 	return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
67 		addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
68 		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
69 		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
70 		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
71 		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
72 }
73 
74 static inline bool
75 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
76 {
77 	const struct flowi6 *fl6 = &fl->u.ip6;
78 
79 	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
80 		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
81 		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
82 		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
83 		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
84 		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
85 }
86 
87 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
88 			 unsigned short family)
89 {
90 	switch (family) {
91 	case AF_INET:
92 		return __xfrm4_selector_match(sel, fl);
93 	case AF_INET6:
94 		return __xfrm6_selector_match(sel, fl);
95 	}
96 	return false;
97 }
98 
99 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
100 {
101 	struct xfrm_policy_afinfo *afinfo;
102 
103 	if (unlikely(family >= NPROTO))
104 		return NULL;
105 	rcu_read_lock();
106 	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
107 	if (unlikely(!afinfo))
108 		rcu_read_unlock();
109 	return afinfo;
110 }
111 
112 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
113 {
114 	rcu_read_unlock();
115 }
116 
117 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
118 						  const xfrm_address_t *saddr,
119 						  const xfrm_address_t *daddr,
120 						  int family)
121 {
122 	struct xfrm_policy_afinfo *afinfo;
123 	struct dst_entry *dst;
124 
125 	afinfo = xfrm_policy_get_afinfo(family);
126 	if (unlikely(afinfo == NULL))
127 		return ERR_PTR(-EAFNOSUPPORT);
128 
129 	dst = afinfo->dst_lookup(net, tos, saddr, daddr);
130 
131 	xfrm_policy_put_afinfo(afinfo);
132 
133 	return dst;
134 }
135 
136 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
137 						xfrm_address_t *prev_saddr,
138 						xfrm_address_t *prev_daddr,
139 						int family)
140 {
141 	struct net *net = xs_net(x);
142 	xfrm_address_t *saddr = &x->props.saddr;
143 	xfrm_address_t *daddr = &x->id.daddr;
144 	struct dst_entry *dst;
145 
146 	if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
147 		saddr = x->coaddr;
148 		daddr = prev_daddr;
149 	}
150 	if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
151 		saddr = prev_saddr;
152 		daddr = x->coaddr;
153 	}
154 
155 	dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
156 
157 	if (!IS_ERR(dst)) {
158 		if (prev_saddr != saddr)
159 			memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
160 		if (prev_daddr != daddr)
161 			memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
162 	}
163 
164 	return dst;
165 }
166 
167 static inline unsigned long make_jiffies(long secs)
168 {
169 	if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
170 		return MAX_SCHEDULE_TIMEOUT-1;
171 	else
172 		return secs*HZ;
173 }
174 
175 static void xfrm_policy_timer(unsigned long data)
176 {
177 	struct xfrm_policy *xp = (struct xfrm_policy *)data;
178 	unsigned long now = get_seconds();
179 	long next = LONG_MAX;
180 	int warn = 0;
181 	int dir;
182 
183 	read_lock(&xp->lock);
184 
185 	if (unlikely(xp->walk.dead))
186 		goto out;
187 
188 	dir = xfrm_policy_id2dir(xp->index);
189 
190 	if (xp->lft.hard_add_expires_seconds) {
191 		long tmo = xp->lft.hard_add_expires_seconds +
192 			xp->curlft.add_time - now;
193 		if (tmo <= 0)
194 			goto expired;
195 		if (tmo < next)
196 			next = tmo;
197 	}
198 	if (xp->lft.hard_use_expires_seconds) {
199 		long tmo = xp->lft.hard_use_expires_seconds +
200 			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
201 		if (tmo <= 0)
202 			goto expired;
203 		if (tmo < next)
204 			next = tmo;
205 	}
206 	if (xp->lft.soft_add_expires_seconds) {
207 		long tmo = xp->lft.soft_add_expires_seconds +
208 			xp->curlft.add_time - now;
209 		if (tmo <= 0) {
210 			warn = 1;
211 			tmo = XFRM_KM_TIMEOUT;
212 		}
213 		if (tmo < next)
214 			next = tmo;
215 	}
216 	if (xp->lft.soft_use_expires_seconds) {
217 		long tmo = xp->lft.soft_use_expires_seconds +
218 			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
219 		if (tmo <= 0) {
220 			warn = 1;
221 			tmo = XFRM_KM_TIMEOUT;
222 		}
223 		if (tmo < next)
224 			next = tmo;
225 	}
226 
227 	if (warn)
228 		km_policy_expired(xp, dir, 0, 0);
229 	if (next != LONG_MAX &&
230 	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
231 		xfrm_pol_hold(xp);
232 
233 out:
234 	read_unlock(&xp->lock);
235 	xfrm_pol_put(xp);
236 	return;
237 
238 expired:
239 	read_unlock(&xp->lock);
240 	if (!xfrm_policy_delete(xp, dir))
241 		km_policy_expired(xp, dir, 1, 0);
242 	xfrm_pol_put(xp);
243 }
244 
245 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
246 {
247 	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
248 
249 	if (unlikely(pol->walk.dead))
250 		flo = NULL;
251 	else
252 		xfrm_pol_hold(pol);
253 
254 	return flo;
255 }
256 
257 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
258 {
259 	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
260 
261 	return !pol->walk.dead;
262 }
263 
264 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
265 {
266 	xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
267 }
268 
269 static const struct flow_cache_ops xfrm_policy_fc_ops = {
270 	.get = xfrm_policy_flo_get,
271 	.check = xfrm_policy_flo_check,
272 	.delete = xfrm_policy_flo_delete,
273 };
274 
275 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
276  * SPD calls.
277  */
278 
279 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
280 {
281 	struct xfrm_policy *policy;
282 
283 	policy = kzalloc(sizeof(struct xfrm_policy), gfp);
284 
285 	if (policy) {
286 		write_pnet(&policy->xp_net, net);
287 		INIT_LIST_HEAD(&policy->walk.all);
288 		INIT_HLIST_NODE(&policy->bydst);
289 		INIT_HLIST_NODE(&policy->byidx);
290 		rwlock_init(&policy->lock);
291 		atomic_set(&policy->refcnt, 1);
292 		skb_queue_head_init(&policy->polq.hold_queue);
293 		setup_timer(&policy->timer, xfrm_policy_timer,
294 				(unsigned long)policy);
295 		setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
296 			    (unsigned long)policy);
297 		policy->flo.ops = &xfrm_policy_fc_ops;
298 	}
299 	return policy;
300 }
301 EXPORT_SYMBOL(xfrm_policy_alloc);
302 
303 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
304 
305 void xfrm_policy_destroy(struct xfrm_policy *policy)
306 {
307 	BUG_ON(!policy->walk.dead);
308 
309 	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
310 		BUG();
311 
312 	security_xfrm_policy_free(policy->security);
313 	kfree(policy);
314 }
315 EXPORT_SYMBOL(xfrm_policy_destroy);
316 
317 static void xfrm_queue_purge(struct sk_buff_head *list)
318 {
319 	struct sk_buff *skb;
320 
321 	while ((skb = skb_dequeue(list)) != NULL)
322 		kfree_skb(skb);
323 }
324 
325 /* Rule must be locked. Release descentant resources, announce
326  * entry dead. The rule must be unlinked from lists to the moment.
327  */
328 
329 static void xfrm_policy_kill(struct xfrm_policy *policy)
330 {
331 	policy->walk.dead = 1;
332 
333 	atomic_inc(&policy->genid);
334 
335 	if (del_timer(&policy->polq.hold_timer))
336 		xfrm_pol_put(policy);
337 	xfrm_queue_purge(&policy->polq.hold_queue);
338 
339 	if (del_timer(&policy->timer))
340 		xfrm_pol_put(policy);
341 
342 	xfrm_pol_put(policy);
343 }
344 
345 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
346 
347 static inline unsigned int idx_hash(struct net *net, u32 index)
348 {
349 	return __idx_hash(index, net->xfrm.policy_idx_hmask);
350 }
351 
352 /* calculate policy hash thresholds */
353 static void __get_hash_thresh(struct net *net,
354 			      unsigned short family, int dir,
355 			      u8 *dbits, u8 *sbits)
356 {
357 	switch (family) {
358 	case AF_INET:
359 		*dbits = net->xfrm.policy_bydst[dir].dbits4;
360 		*sbits = net->xfrm.policy_bydst[dir].sbits4;
361 		break;
362 
363 	case AF_INET6:
364 		*dbits = net->xfrm.policy_bydst[dir].dbits6;
365 		*sbits = net->xfrm.policy_bydst[dir].sbits6;
366 		break;
367 
368 	default:
369 		*dbits = 0;
370 		*sbits = 0;
371 	}
372 }
373 
374 static struct hlist_head *policy_hash_bysel(struct net *net,
375 					    const struct xfrm_selector *sel,
376 					    unsigned short family, int dir)
377 {
378 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
379 	unsigned int hash;
380 	u8 dbits;
381 	u8 sbits;
382 
383 	__get_hash_thresh(net, family, dir, &dbits, &sbits);
384 	hash = __sel_hash(sel, family, hmask, dbits, sbits);
385 
386 	return (hash == hmask + 1 ?
387 		&net->xfrm.policy_inexact[dir] :
388 		net->xfrm.policy_bydst[dir].table + hash);
389 }
390 
391 static struct hlist_head *policy_hash_direct(struct net *net,
392 					     const xfrm_address_t *daddr,
393 					     const xfrm_address_t *saddr,
394 					     unsigned short family, int dir)
395 {
396 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
397 	unsigned int hash;
398 	u8 dbits;
399 	u8 sbits;
400 
401 	__get_hash_thresh(net, family, dir, &dbits, &sbits);
402 	hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
403 
404 	return net->xfrm.policy_bydst[dir].table + hash;
405 }
406 
407 static void xfrm_dst_hash_transfer(struct net *net,
408 				   struct hlist_head *list,
409 				   struct hlist_head *ndsttable,
410 				   unsigned int nhashmask,
411 				   int dir)
412 {
413 	struct hlist_node *tmp, *entry0 = NULL;
414 	struct xfrm_policy *pol;
415 	unsigned int h0 = 0;
416 	u8 dbits;
417 	u8 sbits;
418 
419 redo:
420 	hlist_for_each_entry_safe(pol, tmp, list, bydst) {
421 		unsigned int h;
422 
423 		__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
424 		h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
425 				pol->family, nhashmask, dbits, sbits);
426 		if (!entry0) {
427 			hlist_del(&pol->bydst);
428 			hlist_add_head(&pol->bydst, ndsttable+h);
429 			h0 = h;
430 		} else {
431 			if (h != h0)
432 				continue;
433 			hlist_del(&pol->bydst);
434 			hlist_add_behind(&pol->bydst, entry0);
435 		}
436 		entry0 = &pol->bydst;
437 	}
438 	if (!hlist_empty(list)) {
439 		entry0 = NULL;
440 		goto redo;
441 	}
442 }
443 
444 static void xfrm_idx_hash_transfer(struct hlist_head *list,
445 				   struct hlist_head *nidxtable,
446 				   unsigned int nhashmask)
447 {
448 	struct hlist_node *tmp;
449 	struct xfrm_policy *pol;
450 
451 	hlist_for_each_entry_safe(pol, tmp, list, byidx) {
452 		unsigned int h;
453 
454 		h = __idx_hash(pol->index, nhashmask);
455 		hlist_add_head(&pol->byidx, nidxtable+h);
456 	}
457 }
458 
459 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
460 {
461 	return ((old_hmask + 1) << 1) - 1;
462 }
463 
464 static void xfrm_bydst_resize(struct net *net, int dir)
465 {
466 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
467 	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
468 	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
469 	struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
470 	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
471 	int i;
472 
473 	if (!ndst)
474 		return;
475 
476 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
477 
478 	for (i = hmask; i >= 0; i--)
479 		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
480 
481 	net->xfrm.policy_bydst[dir].table = ndst;
482 	net->xfrm.policy_bydst[dir].hmask = nhashmask;
483 
484 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
485 
486 	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
487 }
488 
489 static void xfrm_byidx_resize(struct net *net, int total)
490 {
491 	unsigned int hmask = net->xfrm.policy_idx_hmask;
492 	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
493 	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
494 	struct hlist_head *oidx = net->xfrm.policy_byidx;
495 	struct hlist_head *nidx = xfrm_hash_alloc(nsize);
496 	int i;
497 
498 	if (!nidx)
499 		return;
500 
501 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
502 
503 	for (i = hmask; i >= 0; i--)
504 		xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
505 
506 	net->xfrm.policy_byidx = nidx;
507 	net->xfrm.policy_idx_hmask = nhashmask;
508 
509 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
510 
511 	xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
512 }
513 
514 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
515 {
516 	unsigned int cnt = net->xfrm.policy_count[dir];
517 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
518 
519 	if (total)
520 		*total += cnt;
521 
522 	if ((hmask + 1) < xfrm_policy_hashmax &&
523 	    cnt > hmask)
524 		return 1;
525 
526 	return 0;
527 }
528 
529 static inline int xfrm_byidx_should_resize(struct net *net, int total)
530 {
531 	unsigned int hmask = net->xfrm.policy_idx_hmask;
532 
533 	if ((hmask + 1) < xfrm_policy_hashmax &&
534 	    total > hmask)
535 		return 1;
536 
537 	return 0;
538 }
539 
540 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
541 {
542 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
543 	si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
544 	si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
545 	si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
546 	si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
547 	si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
548 	si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
549 	si->spdhcnt = net->xfrm.policy_idx_hmask;
550 	si->spdhmcnt = xfrm_policy_hashmax;
551 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
552 }
553 EXPORT_SYMBOL(xfrm_spd_getinfo);
554 
555 static DEFINE_MUTEX(hash_resize_mutex);
556 static void xfrm_hash_resize(struct work_struct *work)
557 {
558 	struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
559 	int dir, total;
560 
561 	mutex_lock(&hash_resize_mutex);
562 
563 	total = 0;
564 	for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
565 		if (xfrm_bydst_should_resize(net, dir, &total))
566 			xfrm_bydst_resize(net, dir);
567 	}
568 	if (xfrm_byidx_should_resize(net, total))
569 		xfrm_byidx_resize(net, total);
570 
571 	mutex_unlock(&hash_resize_mutex);
572 }
573 
574 static void xfrm_hash_rebuild(struct work_struct *work)
575 {
576 	struct net *net = container_of(work, struct net,
577 				       xfrm.policy_hthresh.work);
578 	unsigned int hmask;
579 	struct xfrm_policy *pol;
580 	struct xfrm_policy *policy;
581 	struct hlist_head *chain;
582 	struct hlist_head *odst;
583 	struct hlist_node *newpos;
584 	int i;
585 	int dir;
586 	unsigned seq;
587 	u8 lbits4, rbits4, lbits6, rbits6;
588 
589 	mutex_lock(&hash_resize_mutex);
590 
591 	/* read selector prefixlen thresholds */
592 	do {
593 		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
594 
595 		lbits4 = net->xfrm.policy_hthresh.lbits4;
596 		rbits4 = net->xfrm.policy_hthresh.rbits4;
597 		lbits6 = net->xfrm.policy_hthresh.lbits6;
598 		rbits6 = net->xfrm.policy_hthresh.rbits6;
599 	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
600 
601 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
602 
603 	/* reset the bydst and inexact table in all directions */
604 	for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
605 		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
606 		hmask = net->xfrm.policy_bydst[dir].hmask;
607 		odst = net->xfrm.policy_bydst[dir].table;
608 		for (i = hmask; i >= 0; i--)
609 			INIT_HLIST_HEAD(odst + i);
610 		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
611 			/* dir out => dst = remote, src = local */
612 			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
613 			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
614 			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
615 			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
616 		} else {
617 			/* dir in/fwd => dst = local, src = remote */
618 			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
619 			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
620 			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
621 			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
622 		}
623 	}
624 
625 	/* re-insert all policies by order of creation */
626 	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
627 		newpos = NULL;
628 		chain = policy_hash_bysel(net, &policy->selector,
629 					  policy->family,
630 					  xfrm_policy_id2dir(policy->index));
631 		hlist_for_each_entry(pol, chain, bydst) {
632 			if (policy->priority >= pol->priority)
633 				newpos = &pol->bydst;
634 			else
635 				break;
636 		}
637 		if (newpos)
638 			hlist_add_behind(&policy->bydst, newpos);
639 		else
640 			hlist_add_head(&policy->bydst, chain);
641 	}
642 
643 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
644 
645 	mutex_unlock(&hash_resize_mutex);
646 }
647 
648 void xfrm_policy_hash_rebuild(struct net *net)
649 {
650 	schedule_work(&net->xfrm.policy_hthresh.work);
651 }
652 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
653 
654 /* Generate new index... KAME seems to generate them ordered by cost
655  * of an absolute inpredictability of ordering of rules. This will not pass. */
656 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
657 {
658 	static u32 idx_generator;
659 
660 	for (;;) {
661 		struct hlist_head *list;
662 		struct xfrm_policy *p;
663 		u32 idx;
664 		int found;
665 
666 		if (!index) {
667 			idx = (idx_generator | dir);
668 			idx_generator += 8;
669 		} else {
670 			idx = index;
671 			index = 0;
672 		}
673 
674 		if (idx == 0)
675 			idx = 8;
676 		list = net->xfrm.policy_byidx + idx_hash(net, idx);
677 		found = 0;
678 		hlist_for_each_entry(p, list, byidx) {
679 			if (p->index == idx) {
680 				found = 1;
681 				break;
682 			}
683 		}
684 		if (!found)
685 			return idx;
686 	}
687 }
688 
689 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
690 {
691 	u32 *p1 = (u32 *) s1;
692 	u32 *p2 = (u32 *) s2;
693 	int len = sizeof(struct xfrm_selector) / sizeof(u32);
694 	int i;
695 
696 	for (i = 0; i < len; i++) {
697 		if (p1[i] != p2[i])
698 			return 1;
699 	}
700 
701 	return 0;
702 }
703 
704 static void xfrm_policy_requeue(struct xfrm_policy *old,
705 				struct xfrm_policy *new)
706 {
707 	struct xfrm_policy_queue *pq = &old->polq;
708 	struct sk_buff_head list;
709 
710 	__skb_queue_head_init(&list);
711 
712 	spin_lock_bh(&pq->hold_queue.lock);
713 	skb_queue_splice_init(&pq->hold_queue, &list);
714 	if (del_timer(&pq->hold_timer))
715 		xfrm_pol_put(old);
716 	spin_unlock_bh(&pq->hold_queue.lock);
717 
718 	if (skb_queue_empty(&list))
719 		return;
720 
721 	pq = &new->polq;
722 
723 	spin_lock_bh(&pq->hold_queue.lock);
724 	skb_queue_splice(&list, &pq->hold_queue);
725 	pq->timeout = XFRM_QUEUE_TMO_MIN;
726 	if (!mod_timer(&pq->hold_timer, jiffies))
727 		xfrm_pol_hold(new);
728 	spin_unlock_bh(&pq->hold_queue.lock);
729 }
730 
731 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
732 				   struct xfrm_policy *pol)
733 {
734 	u32 mark = policy->mark.v & policy->mark.m;
735 
736 	if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
737 		return true;
738 
739 	if ((mark & pol->mark.m) == pol->mark.v &&
740 	    policy->priority == pol->priority)
741 		return true;
742 
743 	return false;
744 }
745 
746 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
747 {
748 	struct net *net = xp_net(policy);
749 	struct xfrm_policy *pol;
750 	struct xfrm_policy *delpol;
751 	struct hlist_head *chain;
752 	struct hlist_node *newpos;
753 
754 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
755 	chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
756 	delpol = NULL;
757 	newpos = NULL;
758 	hlist_for_each_entry(pol, chain, bydst) {
759 		if (pol->type == policy->type &&
760 		    !selector_cmp(&pol->selector, &policy->selector) &&
761 		    xfrm_policy_mark_match(policy, pol) &&
762 		    xfrm_sec_ctx_match(pol->security, policy->security) &&
763 		    !WARN_ON(delpol)) {
764 			if (excl) {
765 				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
766 				return -EEXIST;
767 			}
768 			delpol = pol;
769 			if (policy->priority > pol->priority)
770 				continue;
771 		} else if (policy->priority >= pol->priority) {
772 			newpos = &pol->bydst;
773 			continue;
774 		}
775 		if (delpol)
776 			break;
777 	}
778 	if (newpos)
779 		hlist_add_behind(&policy->bydst, newpos);
780 	else
781 		hlist_add_head(&policy->bydst, chain);
782 	xfrm_pol_hold(policy);
783 	net->xfrm.policy_count[dir]++;
784 	atomic_inc(&net->xfrm.flow_cache_genid);
785 
786 	/* After previous checking, family can either be AF_INET or AF_INET6 */
787 	if (policy->family == AF_INET)
788 		rt_genid_bump_ipv4(net);
789 	else
790 		rt_genid_bump_ipv6(net);
791 
792 	if (delpol) {
793 		xfrm_policy_requeue(delpol, policy);
794 		__xfrm_policy_unlink(delpol, dir);
795 	}
796 	policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
797 	hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
798 	policy->curlft.add_time = get_seconds();
799 	policy->curlft.use_time = 0;
800 	if (!mod_timer(&policy->timer, jiffies + HZ))
801 		xfrm_pol_hold(policy);
802 	list_add(&policy->walk.all, &net->xfrm.policy_all);
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_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
1017 	list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1018 		if (x->dead)
1019 			continue;
1020 		pol = container_of(x, struct xfrm_policy, walk);
1021 		if (walk->type != XFRM_POLICY_TYPE_ANY &&
1022 		    walk->type != pol->type)
1023 			continue;
1024 		error = func(pol, xfrm_policy_id2dir(pol->index),
1025 			     walk->seq, data);
1026 		if (error) {
1027 			list_move_tail(&walk->walk.all, &x->all);
1028 			goto out;
1029 		}
1030 		walk->seq++;
1031 	}
1032 	if (walk->seq == 0) {
1033 		error = -ENOENT;
1034 		goto out;
1035 	}
1036 	list_del_init(&walk->walk.all);
1037 out:
1038 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1039 	return error;
1040 }
1041 EXPORT_SYMBOL(xfrm_policy_walk);
1042 
1043 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1044 {
1045 	INIT_LIST_HEAD(&walk->walk.all);
1046 	walk->walk.dead = 1;
1047 	walk->type = type;
1048 	walk->seq = 0;
1049 }
1050 EXPORT_SYMBOL(xfrm_policy_walk_init);
1051 
1052 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1053 {
1054 	if (list_empty(&walk->walk.all))
1055 		return;
1056 
1057 	write_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1058 	list_del(&walk->walk.all);
1059 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1060 }
1061 EXPORT_SYMBOL(xfrm_policy_walk_done);
1062 
1063 /*
1064  * Find policy to apply to this flow.
1065  *
1066  * Returns 0 if policy found, else an -errno.
1067  */
1068 static int xfrm_policy_match(const struct xfrm_policy *pol,
1069 			     const struct flowi *fl,
1070 			     u8 type, u16 family, int dir)
1071 {
1072 	const struct xfrm_selector *sel = &pol->selector;
1073 	int ret = -ESRCH;
1074 	bool match;
1075 
1076 	if (pol->family != family ||
1077 	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1078 	    pol->type != type)
1079 		return ret;
1080 
1081 	match = xfrm_selector_match(sel, fl, family);
1082 	if (match)
1083 		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1084 						  dir);
1085 
1086 	return ret;
1087 }
1088 
1089 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1090 						     const struct flowi *fl,
1091 						     u16 family, u8 dir)
1092 {
1093 	int err;
1094 	struct xfrm_policy *pol, *ret;
1095 	const xfrm_address_t *daddr, *saddr;
1096 	struct hlist_head *chain;
1097 	u32 priority = ~0U;
1098 
1099 	daddr = xfrm_flowi_daddr(fl, family);
1100 	saddr = xfrm_flowi_saddr(fl, family);
1101 	if (unlikely(!daddr || !saddr))
1102 		return NULL;
1103 
1104 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
1105 	chain = policy_hash_direct(net, daddr, saddr, family, dir);
1106 	ret = NULL;
1107 	hlist_for_each_entry(pol, chain, bydst) {
1108 		err = xfrm_policy_match(pol, fl, type, family, dir);
1109 		if (err) {
1110 			if (err == -ESRCH)
1111 				continue;
1112 			else {
1113 				ret = ERR_PTR(err);
1114 				goto fail;
1115 			}
1116 		} else {
1117 			ret = pol;
1118 			priority = ret->priority;
1119 			break;
1120 		}
1121 	}
1122 	chain = &net->xfrm.policy_inexact[dir];
1123 	hlist_for_each_entry(pol, chain, bydst) {
1124 		err = xfrm_policy_match(pol, fl, type, family, dir);
1125 		if (err) {
1126 			if (err == -ESRCH)
1127 				continue;
1128 			else {
1129 				ret = ERR_PTR(err);
1130 				goto fail;
1131 			}
1132 		} else if (pol->priority < priority) {
1133 			ret = pol;
1134 			break;
1135 		}
1136 	}
1137 	if (ret)
1138 		xfrm_pol_hold(ret);
1139 fail:
1140 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
1141 
1142 	return ret;
1143 }
1144 
1145 static struct xfrm_policy *
1146 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1147 {
1148 #ifdef CONFIG_XFRM_SUB_POLICY
1149 	struct xfrm_policy *pol;
1150 
1151 	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1152 	if (pol != NULL)
1153 		return pol;
1154 #endif
1155 	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1156 }
1157 
1158 static int flow_to_policy_dir(int dir)
1159 {
1160 	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1161 	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1162 	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
1163 		return dir;
1164 
1165 	switch (dir) {
1166 	default:
1167 	case FLOW_DIR_IN:
1168 		return XFRM_POLICY_IN;
1169 	case FLOW_DIR_OUT:
1170 		return XFRM_POLICY_OUT;
1171 	case FLOW_DIR_FWD:
1172 		return XFRM_POLICY_FWD;
1173 	}
1174 }
1175 
1176 static struct flow_cache_object *
1177 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1178 		   u8 dir, struct flow_cache_object *old_obj, void *ctx)
1179 {
1180 	struct xfrm_policy *pol;
1181 
1182 	if (old_obj)
1183 		xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1184 
1185 	pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
1186 	if (IS_ERR_OR_NULL(pol))
1187 		return ERR_CAST(pol);
1188 
1189 	/* Resolver returns two references:
1190 	 * one for cache and one for caller of flow_cache_lookup() */
1191 	xfrm_pol_hold(pol);
1192 
1193 	return &pol->flo;
1194 }
1195 
1196 static inline int policy_to_flow_dir(int dir)
1197 {
1198 	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1199 	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1200 	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
1201 		return dir;
1202 	switch (dir) {
1203 	default:
1204 	case XFRM_POLICY_IN:
1205 		return FLOW_DIR_IN;
1206 	case XFRM_POLICY_OUT:
1207 		return FLOW_DIR_OUT;
1208 	case XFRM_POLICY_FWD:
1209 		return FLOW_DIR_FWD;
1210 	}
1211 }
1212 
1213 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
1214 						 const struct flowi *fl)
1215 {
1216 	struct xfrm_policy *pol;
1217 	struct net *net = sock_net(sk);
1218 
1219 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
1220 	if ((pol = sk->sk_policy[dir]) != NULL) {
1221 		bool match = xfrm_selector_match(&pol->selector, fl,
1222 						 sk->sk_family);
1223 		int err = 0;
1224 
1225 		if (match) {
1226 			if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1227 				pol = NULL;
1228 				goto out;
1229 			}
1230 			err = security_xfrm_policy_lookup(pol->security,
1231 						      fl->flowi_secid,
1232 						      policy_to_flow_dir(dir));
1233 			if (!err)
1234 				xfrm_pol_hold(pol);
1235 			else if (err == -ESRCH)
1236 				pol = NULL;
1237 			else
1238 				pol = ERR_PTR(err);
1239 		} else
1240 			pol = NULL;
1241 	}
1242 out:
1243 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
1244 	return pol;
1245 }
1246 
1247 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1248 {
1249 	struct net *net = xp_net(pol);
1250 	struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1251 						     pol->family, dir);
1252 
1253 	list_add(&pol->walk.all, &net->xfrm.policy_all);
1254 	hlist_add_head(&pol->bydst, chain);
1255 	hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1256 	net->xfrm.policy_count[dir]++;
1257 	xfrm_pol_hold(pol);
1258 
1259 	if (xfrm_bydst_should_resize(net, dir, NULL))
1260 		schedule_work(&net->xfrm.policy_hash_work);
1261 }
1262 
1263 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1264 						int dir)
1265 {
1266 	struct net *net = xp_net(pol);
1267 
1268 	if (hlist_unhashed(&pol->bydst))
1269 		return NULL;
1270 
1271 	hlist_del_init(&pol->bydst);
1272 	hlist_del(&pol->byidx);
1273 	list_del(&pol->walk.all);
1274 	net->xfrm.policy_count[dir]--;
1275 
1276 	return pol;
1277 }
1278 
1279 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1280 {
1281 	struct net *net = xp_net(pol);
1282 
1283 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1284 	pol = __xfrm_policy_unlink(pol, dir);
1285 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1286 	if (pol) {
1287 		xfrm_policy_kill(pol);
1288 		return 0;
1289 	}
1290 	return -ENOENT;
1291 }
1292 EXPORT_SYMBOL(xfrm_policy_delete);
1293 
1294 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1295 {
1296 	struct net *net = xp_net(pol);
1297 	struct xfrm_policy *old_pol;
1298 
1299 #ifdef CONFIG_XFRM_SUB_POLICY
1300 	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1301 		return -EINVAL;
1302 #endif
1303 
1304 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1305 	old_pol = sk->sk_policy[dir];
1306 	sk->sk_policy[dir] = pol;
1307 	if (pol) {
1308 		pol->curlft.add_time = get_seconds();
1309 		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1310 		__xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1311 	}
1312 	if (old_pol) {
1313 		if (pol)
1314 			xfrm_policy_requeue(old_pol, pol);
1315 
1316 		/* Unlinking succeeds always. This is the only function
1317 		 * allowed to delete or replace socket policy.
1318 		 */
1319 		__xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1320 	}
1321 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1322 
1323 	if (old_pol) {
1324 		xfrm_policy_kill(old_pol);
1325 	}
1326 	return 0;
1327 }
1328 
1329 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1330 {
1331 	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1332 	struct net *net = xp_net(old);
1333 
1334 	if (newp) {
1335 		newp->selector = old->selector;
1336 		if (security_xfrm_policy_clone(old->security,
1337 					       &newp->security)) {
1338 			kfree(newp);
1339 			return NULL;  /* ENOMEM */
1340 		}
1341 		newp->lft = old->lft;
1342 		newp->curlft = old->curlft;
1343 		newp->mark = old->mark;
1344 		newp->action = old->action;
1345 		newp->flags = old->flags;
1346 		newp->xfrm_nr = old->xfrm_nr;
1347 		newp->index = old->index;
1348 		newp->type = old->type;
1349 		memcpy(newp->xfrm_vec, old->xfrm_vec,
1350 		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1351 		write_lock_bh(&net->xfrm.xfrm_policy_lock);
1352 		__xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1353 		write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1354 		xfrm_pol_put(newp);
1355 	}
1356 	return newp;
1357 }
1358 
1359 int __xfrm_sk_clone_policy(struct sock *sk)
1360 {
1361 	struct xfrm_policy *p0 = sk->sk_policy[0],
1362 			   *p1 = sk->sk_policy[1];
1363 
1364 	sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1365 	if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1366 		return -ENOMEM;
1367 	if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1368 		return -ENOMEM;
1369 	return 0;
1370 }
1371 
1372 static int
1373 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1374 	       unsigned short family)
1375 {
1376 	int err;
1377 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1378 
1379 	if (unlikely(afinfo == NULL))
1380 		return -EINVAL;
1381 	err = afinfo->get_saddr(net, local, remote);
1382 	xfrm_policy_put_afinfo(afinfo);
1383 	return err;
1384 }
1385 
1386 /* Resolve list of templates for the flow, given policy. */
1387 
1388 static int
1389 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1390 		      struct xfrm_state **xfrm, unsigned short family)
1391 {
1392 	struct net *net = xp_net(policy);
1393 	int nx;
1394 	int i, error;
1395 	xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1396 	xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1397 	xfrm_address_t tmp;
1398 
1399 	for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1400 		struct xfrm_state *x;
1401 		xfrm_address_t *remote = daddr;
1402 		xfrm_address_t *local  = saddr;
1403 		struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1404 
1405 		if (tmpl->mode == XFRM_MODE_TUNNEL ||
1406 		    tmpl->mode == XFRM_MODE_BEET) {
1407 			remote = &tmpl->id.daddr;
1408 			local = &tmpl->saddr;
1409 			if (xfrm_addr_any(local, tmpl->encap_family)) {
1410 				error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family);
1411 				if (error)
1412 					goto fail;
1413 				local = &tmp;
1414 			}
1415 		}
1416 
1417 		x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1418 
1419 		if (x && x->km.state == XFRM_STATE_VALID) {
1420 			xfrm[nx++] = x;
1421 			daddr = remote;
1422 			saddr = local;
1423 			continue;
1424 		}
1425 		if (x) {
1426 			error = (x->km.state == XFRM_STATE_ERROR ?
1427 				 -EINVAL : -EAGAIN);
1428 			xfrm_state_put(x);
1429 		} else if (error == -ESRCH) {
1430 			error = -EAGAIN;
1431 		}
1432 
1433 		if (!tmpl->optional)
1434 			goto fail;
1435 	}
1436 	return nx;
1437 
1438 fail:
1439 	for (nx--; nx >= 0; nx--)
1440 		xfrm_state_put(xfrm[nx]);
1441 	return error;
1442 }
1443 
1444 static int
1445 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1446 		  struct xfrm_state **xfrm, unsigned short family)
1447 {
1448 	struct xfrm_state *tp[XFRM_MAX_DEPTH];
1449 	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1450 	int cnx = 0;
1451 	int error;
1452 	int ret;
1453 	int i;
1454 
1455 	for (i = 0; i < npols; i++) {
1456 		if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1457 			error = -ENOBUFS;
1458 			goto fail;
1459 		}
1460 
1461 		ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1462 		if (ret < 0) {
1463 			error = ret;
1464 			goto fail;
1465 		} else
1466 			cnx += ret;
1467 	}
1468 
1469 	/* found states are sorted for outbound processing */
1470 	if (npols > 1)
1471 		xfrm_state_sort(xfrm, tpp, cnx, family);
1472 
1473 	return cnx;
1474 
1475  fail:
1476 	for (cnx--; cnx >= 0; cnx--)
1477 		xfrm_state_put(tpp[cnx]);
1478 	return error;
1479 
1480 }
1481 
1482 /* Check that the bundle accepts the flow and its components are
1483  * still valid.
1484  */
1485 
1486 static inline int xfrm_get_tos(const struct flowi *fl, int family)
1487 {
1488 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1489 	int tos;
1490 
1491 	if (!afinfo)
1492 		return -EINVAL;
1493 
1494 	tos = afinfo->get_tos(fl);
1495 
1496 	xfrm_policy_put_afinfo(afinfo);
1497 
1498 	return tos;
1499 }
1500 
1501 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1502 {
1503 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1504 	struct dst_entry *dst = &xdst->u.dst;
1505 
1506 	if (xdst->route == NULL) {
1507 		/* Dummy bundle - if it has xfrms we were not
1508 		 * able to build bundle as template resolution failed.
1509 		 * It means we need to try again resolving. */
1510 		if (xdst->num_xfrms > 0)
1511 			return NULL;
1512 	} else if (dst->flags & DST_XFRM_QUEUE) {
1513 		return NULL;
1514 	} else {
1515 		/* Real bundle */
1516 		if (stale_bundle(dst))
1517 			return NULL;
1518 	}
1519 
1520 	dst_hold(dst);
1521 	return flo;
1522 }
1523 
1524 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1525 {
1526 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1527 	struct dst_entry *dst = &xdst->u.dst;
1528 
1529 	if (!xdst->route)
1530 		return 0;
1531 	if (stale_bundle(dst))
1532 		return 0;
1533 
1534 	return 1;
1535 }
1536 
1537 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1538 {
1539 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1540 	struct dst_entry *dst = &xdst->u.dst;
1541 
1542 	dst_free(dst);
1543 }
1544 
1545 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1546 	.get = xfrm_bundle_flo_get,
1547 	.check = xfrm_bundle_flo_check,
1548 	.delete = xfrm_bundle_flo_delete,
1549 };
1550 
1551 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1552 {
1553 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1554 	struct dst_ops *dst_ops;
1555 	struct xfrm_dst *xdst;
1556 
1557 	if (!afinfo)
1558 		return ERR_PTR(-EINVAL);
1559 
1560 	switch (family) {
1561 	case AF_INET:
1562 		dst_ops = &net->xfrm.xfrm4_dst_ops;
1563 		break;
1564 #if IS_ENABLED(CONFIG_IPV6)
1565 	case AF_INET6:
1566 		dst_ops = &net->xfrm.xfrm6_dst_ops;
1567 		break;
1568 #endif
1569 	default:
1570 		BUG();
1571 	}
1572 	xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1573 
1574 	if (likely(xdst)) {
1575 		struct dst_entry *dst = &xdst->u.dst;
1576 
1577 		memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1578 		xdst->flo.ops = &xfrm_bundle_fc_ops;
1579 		if (afinfo->init_dst)
1580 			afinfo->init_dst(net, xdst);
1581 	} else
1582 		xdst = ERR_PTR(-ENOBUFS);
1583 
1584 	xfrm_policy_put_afinfo(afinfo);
1585 
1586 	return xdst;
1587 }
1588 
1589 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1590 				 int nfheader_len)
1591 {
1592 	struct xfrm_policy_afinfo *afinfo =
1593 		xfrm_policy_get_afinfo(dst->ops->family);
1594 	int err;
1595 
1596 	if (!afinfo)
1597 		return -EINVAL;
1598 
1599 	err = afinfo->init_path(path, dst, nfheader_len);
1600 
1601 	xfrm_policy_put_afinfo(afinfo);
1602 
1603 	return err;
1604 }
1605 
1606 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1607 				const struct flowi *fl)
1608 {
1609 	struct xfrm_policy_afinfo *afinfo =
1610 		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1611 	int err;
1612 
1613 	if (!afinfo)
1614 		return -EINVAL;
1615 
1616 	err = afinfo->fill_dst(xdst, dev, fl);
1617 
1618 	xfrm_policy_put_afinfo(afinfo);
1619 
1620 	return err;
1621 }
1622 
1623 
1624 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1625  * all the metrics... Shortly, bundle a bundle.
1626  */
1627 
1628 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1629 					    struct xfrm_state **xfrm, int nx,
1630 					    const struct flowi *fl,
1631 					    struct dst_entry *dst)
1632 {
1633 	struct net *net = xp_net(policy);
1634 	unsigned long now = jiffies;
1635 	struct net_device *dev;
1636 	struct xfrm_mode *inner_mode;
1637 	struct dst_entry *dst_prev = NULL;
1638 	struct dst_entry *dst0 = NULL;
1639 	int i = 0;
1640 	int err;
1641 	int header_len = 0;
1642 	int nfheader_len = 0;
1643 	int trailer_len = 0;
1644 	int tos;
1645 	int family = policy->selector.family;
1646 	xfrm_address_t saddr, daddr;
1647 
1648 	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1649 
1650 	tos = xfrm_get_tos(fl, family);
1651 	err = tos;
1652 	if (tos < 0)
1653 		goto put_states;
1654 
1655 	dst_hold(dst);
1656 
1657 	for (; i < nx; i++) {
1658 		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1659 		struct dst_entry *dst1 = &xdst->u.dst;
1660 
1661 		err = PTR_ERR(xdst);
1662 		if (IS_ERR(xdst)) {
1663 			dst_release(dst);
1664 			goto put_states;
1665 		}
1666 
1667 		if (xfrm[i]->sel.family == AF_UNSPEC) {
1668 			inner_mode = xfrm_ip2inner_mode(xfrm[i],
1669 							xfrm_af2proto(family));
1670 			if (!inner_mode) {
1671 				err = -EAFNOSUPPORT;
1672 				dst_release(dst);
1673 				goto put_states;
1674 			}
1675 		} else
1676 			inner_mode = xfrm[i]->inner_mode;
1677 
1678 		if (!dst_prev)
1679 			dst0 = dst1;
1680 		else {
1681 			dst_prev->child = dst_clone(dst1);
1682 			dst1->flags |= DST_NOHASH;
1683 		}
1684 
1685 		xdst->route = dst;
1686 		dst_copy_metrics(dst1, dst);
1687 
1688 		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1689 			family = xfrm[i]->props.family;
1690 			dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1691 					      family);
1692 			err = PTR_ERR(dst);
1693 			if (IS_ERR(dst))
1694 				goto put_states;
1695 		} else
1696 			dst_hold(dst);
1697 
1698 		dst1->xfrm = xfrm[i];
1699 		xdst->xfrm_genid = xfrm[i]->genid;
1700 
1701 		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1702 		dst1->flags |= DST_HOST;
1703 		dst1->lastuse = now;
1704 
1705 		dst1->input = dst_discard;
1706 		dst1->output = inner_mode->afinfo->output;
1707 
1708 		dst1->next = dst_prev;
1709 		dst_prev = dst1;
1710 
1711 		header_len += xfrm[i]->props.header_len;
1712 		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1713 			nfheader_len += xfrm[i]->props.header_len;
1714 		trailer_len += xfrm[i]->props.trailer_len;
1715 	}
1716 
1717 	dst_prev->child = dst;
1718 	dst0->path = dst;
1719 
1720 	err = -ENODEV;
1721 	dev = dst->dev;
1722 	if (!dev)
1723 		goto free_dst;
1724 
1725 	xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1726 	xfrm_init_pmtu(dst_prev);
1727 
1728 	for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1729 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1730 
1731 		err = xfrm_fill_dst(xdst, dev, fl);
1732 		if (err)
1733 			goto free_dst;
1734 
1735 		dst_prev->header_len = header_len;
1736 		dst_prev->trailer_len = trailer_len;
1737 		header_len -= xdst->u.dst.xfrm->props.header_len;
1738 		trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1739 	}
1740 
1741 out:
1742 	return dst0;
1743 
1744 put_states:
1745 	for (; i < nx; i++)
1746 		xfrm_state_put(xfrm[i]);
1747 free_dst:
1748 	if (dst0)
1749 		dst_free(dst0);
1750 	dst0 = ERR_PTR(err);
1751 	goto out;
1752 }
1753 
1754 #ifdef CONFIG_XFRM_SUB_POLICY
1755 static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
1756 {
1757 	if (!*target) {
1758 		*target = kmalloc(size, GFP_ATOMIC);
1759 		if (!*target)
1760 			return -ENOMEM;
1761 	}
1762 
1763 	memcpy(*target, src, size);
1764 	return 0;
1765 }
1766 #endif
1767 
1768 static int xfrm_dst_update_parent(struct dst_entry *dst,
1769 				  const struct xfrm_selector *sel)
1770 {
1771 #ifdef CONFIG_XFRM_SUB_POLICY
1772 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1773 	return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1774 				   sel, sizeof(*sel));
1775 #else
1776 	return 0;
1777 #endif
1778 }
1779 
1780 static int xfrm_dst_update_origin(struct dst_entry *dst,
1781 				  const struct flowi *fl)
1782 {
1783 #ifdef CONFIG_XFRM_SUB_POLICY
1784 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1785 	return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1786 #else
1787 	return 0;
1788 #endif
1789 }
1790 
1791 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1792 				struct xfrm_policy **pols,
1793 				int *num_pols, int *num_xfrms)
1794 {
1795 	int i;
1796 
1797 	if (*num_pols == 0 || !pols[0]) {
1798 		*num_pols = 0;
1799 		*num_xfrms = 0;
1800 		return 0;
1801 	}
1802 	if (IS_ERR(pols[0]))
1803 		return PTR_ERR(pols[0]);
1804 
1805 	*num_xfrms = pols[0]->xfrm_nr;
1806 
1807 #ifdef CONFIG_XFRM_SUB_POLICY
1808 	if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1809 	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1810 		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1811 						    XFRM_POLICY_TYPE_MAIN,
1812 						    fl, family,
1813 						    XFRM_POLICY_OUT);
1814 		if (pols[1]) {
1815 			if (IS_ERR(pols[1])) {
1816 				xfrm_pols_put(pols, *num_pols);
1817 				return PTR_ERR(pols[1]);
1818 			}
1819 			(*num_pols)++;
1820 			(*num_xfrms) += pols[1]->xfrm_nr;
1821 		}
1822 	}
1823 #endif
1824 	for (i = 0; i < *num_pols; i++) {
1825 		if (pols[i]->action != XFRM_POLICY_ALLOW) {
1826 			*num_xfrms = -1;
1827 			break;
1828 		}
1829 	}
1830 
1831 	return 0;
1832 
1833 }
1834 
1835 static struct xfrm_dst *
1836 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1837 			       const struct flowi *fl, u16 family,
1838 			       struct dst_entry *dst_orig)
1839 {
1840 	struct net *net = xp_net(pols[0]);
1841 	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1842 	struct dst_entry *dst;
1843 	struct xfrm_dst *xdst;
1844 	int err;
1845 
1846 	/* Try to instantiate a bundle */
1847 	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1848 	if (err <= 0) {
1849 		if (err != 0 && err != -EAGAIN)
1850 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1851 		return ERR_PTR(err);
1852 	}
1853 
1854 	dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1855 	if (IS_ERR(dst)) {
1856 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1857 		return ERR_CAST(dst);
1858 	}
1859 
1860 	xdst = (struct xfrm_dst *)dst;
1861 	xdst->num_xfrms = err;
1862 	if (num_pols > 1)
1863 		err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1864 	else
1865 		err = xfrm_dst_update_origin(dst, fl);
1866 	if (unlikely(err)) {
1867 		dst_free(dst);
1868 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1869 		return ERR_PTR(err);
1870 	}
1871 
1872 	xdst->num_pols = num_pols;
1873 	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1874 	xdst->policy_genid = atomic_read(&pols[0]->genid);
1875 
1876 	return xdst;
1877 }
1878 
1879 static void xfrm_policy_queue_process(unsigned long arg)
1880 {
1881 	int err = 0;
1882 	struct sk_buff *skb;
1883 	struct sock *sk;
1884 	struct dst_entry *dst;
1885 	struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1886 	struct xfrm_policy_queue *pq = &pol->polq;
1887 	struct flowi fl;
1888 	struct sk_buff_head list;
1889 
1890 	spin_lock(&pq->hold_queue.lock);
1891 	skb = skb_peek(&pq->hold_queue);
1892 	if (!skb) {
1893 		spin_unlock(&pq->hold_queue.lock);
1894 		goto out;
1895 	}
1896 	dst = skb_dst(skb);
1897 	sk = skb->sk;
1898 	xfrm_decode_session(skb, &fl, dst->ops->family);
1899 	spin_unlock(&pq->hold_queue.lock);
1900 
1901 	dst_hold(dst->path);
1902 	dst = xfrm_lookup(xp_net(pol), dst->path, &fl,
1903 			  sk, 0);
1904 	if (IS_ERR(dst))
1905 		goto purge_queue;
1906 
1907 	if (dst->flags & DST_XFRM_QUEUE) {
1908 		dst_release(dst);
1909 
1910 		if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1911 			goto purge_queue;
1912 
1913 		pq->timeout = pq->timeout << 1;
1914 		if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1915 			xfrm_pol_hold(pol);
1916 	goto out;
1917 	}
1918 
1919 	dst_release(dst);
1920 
1921 	__skb_queue_head_init(&list);
1922 
1923 	spin_lock(&pq->hold_queue.lock);
1924 	pq->timeout = 0;
1925 	skb_queue_splice_init(&pq->hold_queue, &list);
1926 	spin_unlock(&pq->hold_queue.lock);
1927 
1928 	while (!skb_queue_empty(&list)) {
1929 		skb = __skb_dequeue(&list);
1930 
1931 		xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1932 		dst_hold(skb_dst(skb)->path);
1933 		dst = xfrm_lookup(xp_net(pol), skb_dst(skb)->path,
1934 				  &fl, skb->sk, 0);
1935 		if (IS_ERR(dst)) {
1936 			kfree_skb(skb);
1937 			continue;
1938 		}
1939 
1940 		nf_reset(skb);
1941 		skb_dst_drop(skb);
1942 		skb_dst_set(skb, dst);
1943 
1944 		err = dst_output(skb);
1945 	}
1946 
1947 out:
1948 	xfrm_pol_put(pol);
1949 	return;
1950 
1951 purge_queue:
1952 	pq->timeout = 0;
1953 	xfrm_queue_purge(&pq->hold_queue);
1954 	xfrm_pol_put(pol);
1955 }
1956 
1957 static int xdst_queue_output(struct sock *sk, struct sk_buff *skb)
1958 {
1959 	unsigned long sched_next;
1960 	struct dst_entry *dst = skb_dst(skb);
1961 	struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1962 	struct xfrm_policy *pol = xdst->pols[0];
1963 	struct xfrm_policy_queue *pq = &pol->polq;
1964 
1965 	if (unlikely(skb_fclone_busy(sk, skb))) {
1966 		kfree_skb(skb);
1967 		return 0;
1968 	}
1969 
1970 	if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1971 		kfree_skb(skb);
1972 		return -EAGAIN;
1973 	}
1974 
1975 	skb_dst_force(skb);
1976 
1977 	spin_lock_bh(&pq->hold_queue.lock);
1978 
1979 	if (!pq->timeout)
1980 		pq->timeout = XFRM_QUEUE_TMO_MIN;
1981 
1982 	sched_next = jiffies + pq->timeout;
1983 
1984 	if (del_timer(&pq->hold_timer)) {
1985 		if (time_before(pq->hold_timer.expires, sched_next))
1986 			sched_next = pq->hold_timer.expires;
1987 		xfrm_pol_put(pol);
1988 	}
1989 
1990 	__skb_queue_tail(&pq->hold_queue, skb);
1991 	if (!mod_timer(&pq->hold_timer, sched_next))
1992 		xfrm_pol_hold(pol);
1993 
1994 	spin_unlock_bh(&pq->hold_queue.lock);
1995 
1996 	return 0;
1997 }
1998 
1999 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2000 						 struct xfrm_flo *xflo,
2001 						 const struct flowi *fl,
2002 						 int num_xfrms,
2003 						 u16 family)
2004 {
2005 	int err;
2006 	struct net_device *dev;
2007 	struct dst_entry *dst;
2008 	struct dst_entry *dst1;
2009 	struct xfrm_dst *xdst;
2010 
2011 	xdst = xfrm_alloc_dst(net, family);
2012 	if (IS_ERR(xdst))
2013 		return xdst;
2014 
2015 	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2016 	    net->xfrm.sysctl_larval_drop ||
2017 	    num_xfrms <= 0)
2018 		return xdst;
2019 
2020 	dst = xflo->dst_orig;
2021 	dst1 = &xdst->u.dst;
2022 	dst_hold(dst);
2023 	xdst->route = dst;
2024 
2025 	dst_copy_metrics(dst1, dst);
2026 
2027 	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2028 	dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2029 	dst1->lastuse = jiffies;
2030 
2031 	dst1->input = dst_discard;
2032 	dst1->output = xdst_queue_output;
2033 
2034 	dst_hold(dst);
2035 	dst1->child = dst;
2036 	dst1->path = dst;
2037 
2038 	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2039 
2040 	err = -ENODEV;
2041 	dev = dst->dev;
2042 	if (!dev)
2043 		goto free_dst;
2044 
2045 	err = xfrm_fill_dst(xdst, dev, fl);
2046 	if (err)
2047 		goto free_dst;
2048 
2049 out:
2050 	return xdst;
2051 
2052 free_dst:
2053 	dst_release(dst1);
2054 	xdst = ERR_PTR(err);
2055 	goto out;
2056 }
2057 
2058 static struct flow_cache_object *
2059 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
2060 		   struct flow_cache_object *oldflo, void *ctx)
2061 {
2062 	struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
2063 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2064 	struct xfrm_dst *xdst, *new_xdst;
2065 	int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
2066 
2067 	/* Check if the policies from old bundle are usable */
2068 	xdst = NULL;
2069 	if (oldflo) {
2070 		xdst = container_of(oldflo, struct xfrm_dst, flo);
2071 		num_pols = xdst->num_pols;
2072 		num_xfrms = xdst->num_xfrms;
2073 		pol_dead = 0;
2074 		for (i = 0; i < num_pols; i++) {
2075 			pols[i] = xdst->pols[i];
2076 			pol_dead |= pols[i]->walk.dead;
2077 		}
2078 		if (pol_dead) {
2079 			dst_free(&xdst->u.dst);
2080 			xdst = NULL;
2081 			num_pols = 0;
2082 			num_xfrms = 0;
2083 			oldflo = NULL;
2084 		}
2085 	}
2086 
2087 	/* Resolve policies to use if we couldn't get them from
2088 	 * previous cache entry */
2089 	if (xdst == NULL) {
2090 		num_pols = 1;
2091 		pols[0] = __xfrm_policy_lookup(net, fl, family,
2092 					       flow_to_policy_dir(dir));
2093 		err = xfrm_expand_policies(fl, family, pols,
2094 					   &num_pols, &num_xfrms);
2095 		if (err < 0)
2096 			goto inc_error;
2097 		if (num_pols == 0)
2098 			return NULL;
2099 		if (num_xfrms <= 0)
2100 			goto make_dummy_bundle;
2101 	}
2102 
2103 	new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2104 						  xflo->dst_orig);
2105 	if (IS_ERR(new_xdst)) {
2106 		err = PTR_ERR(new_xdst);
2107 		if (err != -EAGAIN)
2108 			goto error;
2109 		if (oldflo == NULL)
2110 			goto make_dummy_bundle;
2111 		dst_hold(&xdst->u.dst);
2112 		return oldflo;
2113 	} else if (new_xdst == NULL) {
2114 		num_xfrms = 0;
2115 		if (oldflo == NULL)
2116 			goto make_dummy_bundle;
2117 		xdst->num_xfrms = 0;
2118 		dst_hold(&xdst->u.dst);
2119 		return oldflo;
2120 	}
2121 
2122 	/* Kill the previous bundle */
2123 	if (xdst) {
2124 		/* The policies were stolen for newly generated bundle */
2125 		xdst->num_pols = 0;
2126 		dst_free(&xdst->u.dst);
2127 	}
2128 
2129 	/* Flow cache does not have reference, it dst_free()'s,
2130 	 * but we do need to return one reference for original caller */
2131 	dst_hold(&new_xdst->u.dst);
2132 	return &new_xdst->flo;
2133 
2134 make_dummy_bundle:
2135 	/* We found policies, but there's no bundles to instantiate:
2136 	 * either because the policy blocks, has no transformations or
2137 	 * we could not build template (no xfrm_states).*/
2138 	xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2139 	if (IS_ERR(xdst)) {
2140 		xfrm_pols_put(pols, num_pols);
2141 		return ERR_CAST(xdst);
2142 	}
2143 	xdst->num_pols = num_pols;
2144 	xdst->num_xfrms = num_xfrms;
2145 	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2146 
2147 	dst_hold(&xdst->u.dst);
2148 	return &xdst->flo;
2149 
2150 inc_error:
2151 	XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2152 error:
2153 	if (xdst != NULL)
2154 		dst_free(&xdst->u.dst);
2155 	else
2156 		xfrm_pols_put(pols, num_pols);
2157 	return ERR_PTR(err);
2158 }
2159 
2160 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2161 					struct dst_entry *dst_orig)
2162 {
2163 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2164 	struct dst_entry *ret;
2165 
2166 	if (!afinfo) {
2167 		dst_release(dst_orig);
2168 		return ERR_PTR(-EINVAL);
2169 	} else {
2170 		ret = afinfo->blackhole_route(net, dst_orig);
2171 	}
2172 	xfrm_policy_put_afinfo(afinfo);
2173 
2174 	return ret;
2175 }
2176 
2177 /* Main function: finds/creates a bundle for given flow.
2178  *
2179  * At the moment we eat a raw IP route. Mostly to speed up lookups
2180  * on interfaces with disabled IPsec.
2181  */
2182 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2183 			      const struct flowi *fl,
2184 			      struct sock *sk, int flags)
2185 {
2186 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2187 	struct flow_cache_object *flo;
2188 	struct xfrm_dst *xdst;
2189 	struct dst_entry *dst, *route;
2190 	u16 family = dst_orig->ops->family;
2191 	u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2192 	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2193 
2194 	dst = NULL;
2195 	xdst = NULL;
2196 	route = NULL;
2197 
2198 	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2199 		num_pols = 1;
2200 		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2201 		err = xfrm_expand_policies(fl, family, pols,
2202 					   &num_pols, &num_xfrms);
2203 		if (err < 0)
2204 			goto dropdst;
2205 
2206 		if (num_pols) {
2207 			if (num_xfrms <= 0) {
2208 				drop_pols = num_pols;
2209 				goto no_transform;
2210 			}
2211 
2212 			xdst = xfrm_resolve_and_create_bundle(
2213 					pols, num_pols, fl,
2214 					family, dst_orig);
2215 			if (IS_ERR(xdst)) {
2216 				xfrm_pols_put(pols, num_pols);
2217 				err = PTR_ERR(xdst);
2218 				goto dropdst;
2219 			} else if (xdst == NULL) {
2220 				num_xfrms = 0;
2221 				drop_pols = num_pols;
2222 				goto no_transform;
2223 			}
2224 
2225 			dst_hold(&xdst->u.dst);
2226 			xdst->u.dst.flags |= DST_NOCACHE;
2227 			route = xdst->route;
2228 		}
2229 	}
2230 
2231 	if (xdst == NULL) {
2232 		struct xfrm_flo xflo;
2233 
2234 		xflo.dst_orig = dst_orig;
2235 		xflo.flags = flags;
2236 
2237 		/* To accelerate a bit...  */
2238 		if ((dst_orig->flags & DST_NOXFRM) ||
2239 		    !net->xfrm.policy_count[XFRM_POLICY_OUT])
2240 			goto nopol;
2241 
2242 		flo = flow_cache_lookup(net, fl, family, dir,
2243 					xfrm_bundle_lookup, &xflo);
2244 		if (flo == NULL)
2245 			goto nopol;
2246 		if (IS_ERR(flo)) {
2247 			err = PTR_ERR(flo);
2248 			goto dropdst;
2249 		}
2250 		xdst = container_of(flo, struct xfrm_dst, flo);
2251 
2252 		num_pols = xdst->num_pols;
2253 		num_xfrms = xdst->num_xfrms;
2254 		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2255 		route = xdst->route;
2256 	}
2257 
2258 	dst = &xdst->u.dst;
2259 	if (route == NULL && num_xfrms > 0) {
2260 		/* The only case when xfrm_bundle_lookup() returns a
2261 		 * bundle with null route, is when the template could
2262 		 * not be resolved. It means policies are there, but
2263 		 * bundle could not be created, since we don't yet
2264 		 * have the xfrm_state's. We need to wait for KM to
2265 		 * negotiate new SA's or bail out with error.*/
2266 		if (net->xfrm.sysctl_larval_drop) {
2267 			dst_release(dst);
2268 			xfrm_pols_put(pols, drop_pols);
2269 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2270 
2271 			return ERR_PTR(-EREMOTE);
2272 		}
2273 
2274 		err = -EAGAIN;
2275 
2276 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2277 		goto error;
2278 	}
2279 
2280 no_transform:
2281 	if (num_pols == 0)
2282 		goto nopol;
2283 
2284 	if ((flags & XFRM_LOOKUP_ICMP) &&
2285 	    !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2286 		err = -ENOENT;
2287 		goto error;
2288 	}
2289 
2290 	for (i = 0; i < num_pols; i++)
2291 		pols[i]->curlft.use_time = get_seconds();
2292 
2293 	if (num_xfrms < 0) {
2294 		/* Prohibit the flow */
2295 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2296 		err = -EPERM;
2297 		goto error;
2298 	} else if (num_xfrms > 0) {
2299 		/* Flow transformed */
2300 		dst_release(dst_orig);
2301 	} else {
2302 		/* Flow passes untransformed */
2303 		dst_release(dst);
2304 		dst = dst_orig;
2305 	}
2306 ok:
2307 	xfrm_pols_put(pols, drop_pols);
2308 	if (dst && dst->xfrm &&
2309 	    dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2310 		dst->flags |= DST_XFRM_TUNNEL;
2311 	return dst;
2312 
2313 nopol:
2314 	if (!(flags & XFRM_LOOKUP_ICMP)) {
2315 		dst = dst_orig;
2316 		goto ok;
2317 	}
2318 	err = -ENOENT;
2319 error:
2320 	dst_release(dst);
2321 dropdst:
2322 	dst_release(dst_orig);
2323 	xfrm_pols_put(pols, drop_pols);
2324 	return ERR_PTR(err);
2325 }
2326 EXPORT_SYMBOL(xfrm_lookup);
2327 
2328 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2329  * Otherwise we may send out blackholed packets.
2330  */
2331 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2332 				    const struct flowi *fl,
2333 				    struct sock *sk, int flags)
2334 {
2335 	struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2336 					    flags | XFRM_LOOKUP_QUEUE);
2337 
2338 	if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2339 		return make_blackhole(net, dst_orig->ops->family, dst_orig);
2340 
2341 	return dst;
2342 }
2343 EXPORT_SYMBOL(xfrm_lookup_route);
2344 
2345 static inline int
2346 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2347 {
2348 	struct xfrm_state *x;
2349 
2350 	if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2351 		return 0;
2352 	x = skb->sp->xvec[idx];
2353 	if (!x->type->reject)
2354 		return 0;
2355 	return x->type->reject(x, skb, fl);
2356 }
2357 
2358 /* When skb is transformed back to its "native" form, we have to
2359  * check policy restrictions. At the moment we make this in maximally
2360  * stupid way. Shame on me. :-) Of course, connected sockets must
2361  * have policy cached at them.
2362  */
2363 
2364 static inline int
2365 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2366 	      unsigned short family)
2367 {
2368 	if (xfrm_state_kern(x))
2369 		return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2370 	return	x->id.proto == tmpl->id.proto &&
2371 		(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2372 		(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2373 		x->props.mode == tmpl->mode &&
2374 		(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2375 		 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2376 		!(x->props.mode != XFRM_MODE_TRANSPORT &&
2377 		  xfrm_state_addr_cmp(tmpl, x, family));
2378 }
2379 
2380 /*
2381  * 0 or more than 0 is returned when validation is succeeded (either bypass
2382  * because of optional transport mode, or next index of the mathced secpath
2383  * state with the template.
2384  * -1 is returned when no matching template is found.
2385  * Otherwise "-2 - errored_index" is returned.
2386  */
2387 static inline int
2388 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2389 	       unsigned short family)
2390 {
2391 	int idx = start;
2392 
2393 	if (tmpl->optional) {
2394 		if (tmpl->mode == XFRM_MODE_TRANSPORT)
2395 			return start;
2396 	} else
2397 		start = -1;
2398 	for (; idx < sp->len; idx++) {
2399 		if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2400 			return ++idx;
2401 		if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2402 			if (start == -1)
2403 				start = -2-idx;
2404 			break;
2405 		}
2406 	}
2407 	return start;
2408 }
2409 
2410 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2411 			  unsigned int family, int reverse)
2412 {
2413 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2414 	int err;
2415 
2416 	if (unlikely(afinfo == NULL))
2417 		return -EAFNOSUPPORT;
2418 
2419 	afinfo->decode_session(skb, fl, reverse);
2420 	err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2421 	xfrm_policy_put_afinfo(afinfo);
2422 	return err;
2423 }
2424 EXPORT_SYMBOL(__xfrm_decode_session);
2425 
2426 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2427 {
2428 	for (; k < sp->len; k++) {
2429 		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2430 			*idxp = k;
2431 			return 1;
2432 		}
2433 	}
2434 
2435 	return 0;
2436 }
2437 
2438 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2439 			unsigned short family)
2440 {
2441 	struct net *net = dev_net(skb->dev);
2442 	struct xfrm_policy *pol;
2443 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2444 	int npols = 0;
2445 	int xfrm_nr;
2446 	int pi;
2447 	int reverse;
2448 	struct flowi fl;
2449 	u8 fl_dir;
2450 	int xerr_idx = -1;
2451 
2452 	reverse = dir & ~XFRM_POLICY_MASK;
2453 	dir &= XFRM_POLICY_MASK;
2454 	fl_dir = policy_to_flow_dir(dir);
2455 
2456 	if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2457 		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2458 		return 0;
2459 	}
2460 
2461 	nf_nat_decode_session(skb, &fl, family);
2462 
2463 	/* First, check used SA against their selectors. */
2464 	if (skb->sp) {
2465 		int i;
2466 
2467 		for (i = skb->sp->len-1; i >= 0; i--) {
2468 			struct xfrm_state *x = skb->sp->xvec[i];
2469 			if (!xfrm_selector_match(&x->sel, &fl, family)) {
2470 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2471 				return 0;
2472 			}
2473 		}
2474 	}
2475 
2476 	pol = NULL;
2477 	if (sk && sk->sk_policy[dir]) {
2478 		pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2479 		if (IS_ERR(pol)) {
2480 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2481 			return 0;
2482 		}
2483 	}
2484 
2485 	if (!pol) {
2486 		struct flow_cache_object *flo;
2487 
2488 		flo = flow_cache_lookup(net, &fl, family, fl_dir,
2489 					xfrm_policy_lookup, NULL);
2490 		if (IS_ERR_OR_NULL(flo))
2491 			pol = ERR_CAST(flo);
2492 		else
2493 			pol = container_of(flo, struct xfrm_policy, flo);
2494 	}
2495 
2496 	if (IS_ERR(pol)) {
2497 		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2498 		return 0;
2499 	}
2500 
2501 	if (!pol) {
2502 		if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2503 			xfrm_secpath_reject(xerr_idx, skb, &fl);
2504 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2505 			return 0;
2506 		}
2507 		return 1;
2508 	}
2509 
2510 	pol->curlft.use_time = get_seconds();
2511 
2512 	pols[0] = pol;
2513 	npols++;
2514 #ifdef CONFIG_XFRM_SUB_POLICY
2515 	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2516 		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2517 						    &fl, family,
2518 						    XFRM_POLICY_IN);
2519 		if (pols[1]) {
2520 			if (IS_ERR(pols[1])) {
2521 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2522 				return 0;
2523 			}
2524 			pols[1]->curlft.use_time = get_seconds();
2525 			npols++;
2526 		}
2527 	}
2528 #endif
2529 
2530 	if (pol->action == XFRM_POLICY_ALLOW) {
2531 		struct sec_path *sp;
2532 		static struct sec_path dummy;
2533 		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2534 		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2535 		struct xfrm_tmpl **tpp = tp;
2536 		int ti = 0;
2537 		int i, k;
2538 
2539 		if ((sp = skb->sp) == NULL)
2540 			sp = &dummy;
2541 
2542 		for (pi = 0; pi < npols; pi++) {
2543 			if (pols[pi] != pol &&
2544 			    pols[pi]->action != XFRM_POLICY_ALLOW) {
2545 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2546 				goto reject;
2547 			}
2548 			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2549 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2550 				goto reject_error;
2551 			}
2552 			for (i = 0; i < pols[pi]->xfrm_nr; i++)
2553 				tpp[ti++] = &pols[pi]->xfrm_vec[i];
2554 		}
2555 		xfrm_nr = ti;
2556 		if (npols > 1) {
2557 			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2558 			tpp = stp;
2559 		}
2560 
2561 		/* For each tunnel xfrm, find the first matching tmpl.
2562 		 * For each tmpl before that, find corresponding xfrm.
2563 		 * Order is _important_. Later we will implement
2564 		 * some barriers, but at the moment barriers
2565 		 * are implied between each two transformations.
2566 		 */
2567 		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2568 			k = xfrm_policy_ok(tpp[i], sp, k, family);
2569 			if (k < 0) {
2570 				if (k < -1)
2571 					/* "-2 - errored_index" returned */
2572 					xerr_idx = -(2+k);
2573 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2574 				goto reject;
2575 			}
2576 		}
2577 
2578 		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2579 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2580 			goto reject;
2581 		}
2582 
2583 		xfrm_pols_put(pols, npols);
2584 		return 1;
2585 	}
2586 	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2587 
2588 reject:
2589 	xfrm_secpath_reject(xerr_idx, skb, &fl);
2590 reject_error:
2591 	xfrm_pols_put(pols, npols);
2592 	return 0;
2593 }
2594 EXPORT_SYMBOL(__xfrm_policy_check);
2595 
2596 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2597 {
2598 	struct net *net = dev_net(skb->dev);
2599 	struct flowi fl;
2600 	struct dst_entry *dst;
2601 	int res = 1;
2602 
2603 	if (xfrm_decode_session(skb, &fl, family) < 0) {
2604 		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2605 		return 0;
2606 	}
2607 
2608 	skb_dst_force(skb);
2609 
2610 	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2611 	if (IS_ERR(dst)) {
2612 		res = 0;
2613 		dst = NULL;
2614 	}
2615 	skb_dst_set(skb, dst);
2616 	return res;
2617 }
2618 EXPORT_SYMBOL(__xfrm_route_forward);
2619 
2620 /* Optimize later using cookies and generation ids. */
2621 
2622 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2623 {
2624 	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2625 	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2626 	 * get validated by dst_ops->check on every use.  We do this
2627 	 * because when a normal route referenced by an XFRM dst is
2628 	 * obsoleted we do not go looking around for all parent
2629 	 * referencing XFRM dsts so that we can invalidate them.  It
2630 	 * is just too much work.  Instead we make the checks here on
2631 	 * every use.  For example:
2632 	 *
2633 	 *	XFRM dst A --> IPv4 dst X
2634 	 *
2635 	 * X is the "xdst->route" of A (X is also the "dst->path" of A
2636 	 * in this example).  If X is marked obsolete, "A" will not
2637 	 * notice.  That's what we are validating here via the
2638 	 * stale_bundle() check.
2639 	 *
2640 	 * When a policy's bundle is pruned, we dst_free() the XFRM
2641 	 * dst which causes it's ->obsolete field to be set to
2642 	 * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2643 	 * this, we want to force a new route lookup.
2644 	 */
2645 	if (dst->obsolete < 0 && !stale_bundle(dst))
2646 		return dst;
2647 
2648 	return NULL;
2649 }
2650 
2651 static int stale_bundle(struct dst_entry *dst)
2652 {
2653 	return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2654 }
2655 
2656 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2657 {
2658 	while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2659 		dst->dev = dev_net(dev)->loopback_dev;
2660 		dev_hold(dst->dev);
2661 		dev_put(dev);
2662 	}
2663 }
2664 EXPORT_SYMBOL(xfrm_dst_ifdown);
2665 
2666 static void xfrm_link_failure(struct sk_buff *skb)
2667 {
2668 	/* Impossible. Such dst must be popped before reaches point of failure. */
2669 }
2670 
2671 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2672 {
2673 	if (dst) {
2674 		if (dst->obsolete) {
2675 			dst_release(dst);
2676 			dst = NULL;
2677 		}
2678 	}
2679 	return dst;
2680 }
2681 
2682 void xfrm_garbage_collect(struct net *net)
2683 {
2684 	flow_cache_flush(net);
2685 }
2686 EXPORT_SYMBOL(xfrm_garbage_collect);
2687 
2688 static void xfrm_garbage_collect_deferred(struct net *net)
2689 {
2690 	flow_cache_flush_deferred(net);
2691 }
2692 
2693 static void xfrm_init_pmtu(struct dst_entry *dst)
2694 {
2695 	do {
2696 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2697 		u32 pmtu, route_mtu_cached;
2698 
2699 		pmtu = dst_mtu(dst->child);
2700 		xdst->child_mtu_cached = pmtu;
2701 
2702 		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2703 
2704 		route_mtu_cached = dst_mtu(xdst->route);
2705 		xdst->route_mtu_cached = route_mtu_cached;
2706 
2707 		if (pmtu > route_mtu_cached)
2708 			pmtu = route_mtu_cached;
2709 
2710 		dst_metric_set(dst, RTAX_MTU, pmtu);
2711 	} while ((dst = dst->next));
2712 }
2713 
2714 /* Check that the bundle accepts the flow and its components are
2715  * still valid.
2716  */
2717 
2718 static int xfrm_bundle_ok(struct xfrm_dst *first)
2719 {
2720 	struct dst_entry *dst = &first->u.dst;
2721 	struct xfrm_dst *last;
2722 	u32 mtu;
2723 
2724 	if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2725 	    (dst->dev && !netif_running(dst->dev)))
2726 		return 0;
2727 
2728 	if (dst->flags & DST_XFRM_QUEUE)
2729 		return 1;
2730 
2731 	last = NULL;
2732 
2733 	do {
2734 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2735 
2736 		if (dst->xfrm->km.state != XFRM_STATE_VALID)
2737 			return 0;
2738 		if (xdst->xfrm_genid != dst->xfrm->genid)
2739 			return 0;
2740 		if (xdst->num_pols > 0 &&
2741 		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2742 			return 0;
2743 
2744 		mtu = dst_mtu(dst->child);
2745 		if (xdst->child_mtu_cached != mtu) {
2746 			last = xdst;
2747 			xdst->child_mtu_cached = mtu;
2748 		}
2749 
2750 		if (!dst_check(xdst->route, xdst->route_cookie))
2751 			return 0;
2752 		mtu = dst_mtu(xdst->route);
2753 		if (xdst->route_mtu_cached != mtu) {
2754 			last = xdst;
2755 			xdst->route_mtu_cached = mtu;
2756 		}
2757 
2758 		dst = dst->child;
2759 	} while (dst->xfrm);
2760 
2761 	if (likely(!last))
2762 		return 1;
2763 
2764 	mtu = last->child_mtu_cached;
2765 	for (;;) {
2766 		dst = &last->u.dst;
2767 
2768 		mtu = xfrm_state_mtu(dst->xfrm, mtu);
2769 		if (mtu > last->route_mtu_cached)
2770 			mtu = last->route_mtu_cached;
2771 		dst_metric_set(dst, RTAX_MTU, mtu);
2772 
2773 		if (last == first)
2774 			break;
2775 
2776 		last = (struct xfrm_dst *)last->u.dst.next;
2777 		last->child_mtu_cached = mtu;
2778 	}
2779 
2780 	return 1;
2781 }
2782 
2783 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2784 {
2785 	return dst_metric_advmss(dst->path);
2786 }
2787 
2788 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2789 {
2790 	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2791 
2792 	return mtu ? : dst_mtu(dst->path);
2793 }
2794 
2795 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2796 					   struct sk_buff *skb,
2797 					   const void *daddr)
2798 {
2799 	return dst->path->ops->neigh_lookup(dst, skb, daddr);
2800 }
2801 
2802 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2803 {
2804 	struct net *net;
2805 	int err = 0;
2806 	if (unlikely(afinfo == NULL))
2807 		return -EINVAL;
2808 	if (unlikely(afinfo->family >= NPROTO))
2809 		return -EAFNOSUPPORT;
2810 	spin_lock(&xfrm_policy_afinfo_lock);
2811 	if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2812 		err = -ENOBUFS;
2813 	else {
2814 		struct dst_ops *dst_ops = afinfo->dst_ops;
2815 		if (likely(dst_ops->kmem_cachep == NULL))
2816 			dst_ops->kmem_cachep = xfrm_dst_cache;
2817 		if (likely(dst_ops->check == NULL))
2818 			dst_ops->check = xfrm_dst_check;
2819 		if (likely(dst_ops->default_advmss == NULL))
2820 			dst_ops->default_advmss = xfrm_default_advmss;
2821 		if (likely(dst_ops->mtu == NULL))
2822 			dst_ops->mtu = xfrm_mtu;
2823 		if (likely(dst_ops->negative_advice == NULL))
2824 			dst_ops->negative_advice = xfrm_negative_advice;
2825 		if (likely(dst_ops->link_failure == NULL))
2826 			dst_ops->link_failure = xfrm_link_failure;
2827 		if (likely(dst_ops->neigh_lookup == NULL))
2828 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
2829 		if (likely(afinfo->garbage_collect == NULL))
2830 			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2831 		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
2832 	}
2833 	spin_unlock(&xfrm_policy_afinfo_lock);
2834 
2835 	rtnl_lock();
2836 	for_each_net(net) {
2837 		struct dst_ops *xfrm_dst_ops;
2838 
2839 		switch (afinfo->family) {
2840 		case AF_INET:
2841 			xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2842 			break;
2843 #if IS_ENABLED(CONFIG_IPV6)
2844 		case AF_INET6:
2845 			xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2846 			break;
2847 #endif
2848 		default:
2849 			BUG();
2850 		}
2851 		*xfrm_dst_ops = *afinfo->dst_ops;
2852 	}
2853 	rtnl_unlock();
2854 
2855 	return err;
2856 }
2857 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2858 
2859 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2860 {
2861 	int err = 0;
2862 	if (unlikely(afinfo == NULL))
2863 		return -EINVAL;
2864 	if (unlikely(afinfo->family >= NPROTO))
2865 		return -EAFNOSUPPORT;
2866 	spin_lock(&xfrm_policy_afinfo_lock);
2867 	if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2868 		if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2869 			err = -EINVAL;
2870 		else
2871 			RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
2872 					 NULL);
2873 	}
2874 	spin_unlock(&xfrm_policy_afinfo_lock);
2875 	if (!err) {
2876 		struct dst_ops *dst_ops = afinfo->dst_ops;
2877 
2878 		synchronize_rcu();
2879 
2880 		dst_ops->kmem_cachep = NULL;
2881 		dst_ops->check = NULL;
2882 		dst_ops->negative_advice = NULL;
2883 		dst_ops->link_failure = NULL;
2884 		afinfo->garbage_collect = NULL;
2885 	}
2886 	return err;
2887 }
2888 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2889 
2890 static void __net_init xfrm_dst_ops_init(struct net *net)
2891 {
2892 	struct xfrm_policy_afinfo *afinfo;
2893 
2894 	rcu_read_lock();
2895 	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]);
2896 	if (afinfo)
2897 		net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2898 #if IS_ENABLED(CONFIG_IPV6)
2899 	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]);
2900 	if (afinfo)
2901 		net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2902 #endif
2903 	rcu_read_unlock();
2904 }
2905 
2906 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2907 {
2908 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2909 
2910 	switch (event) {
2911 	case NETDEV_DOWN:
2912 		xfrm_garbage_collect(dev_net(dev));
2913 	}
2914 	return NOTIFY_DONE;
2915 }
2916 
2917 static struct notifier_block xfrm_dev_notifier = {
2918 	.notifier_call	= xfrm_dev_event,
2919 };
2920 
2921 #ifdef CONFIG_XFRM_STATISTICS
2922 static int __net_init xfrm_statistics_init(struct net *net)
2923 {
2924 	int rv;
2925 	net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2926 	if (!net->mib.xfrm_statistics)
2927 		return -ENOMEM;
2928 	rv = xfrm_proc_init(net);
2929 	if (rv < 0)
2930 		free_percpu(net->mib.xfrm_statistics);
2931 	return rv;
2932 }
2933 
2934 static void xfrm_statistics_fini(struct net *net)
2935 {
2936 	xfrm_proc_fini(net);
2937 	free_percpu(net->mib.xfrm_statistics);
2938 }
2939 #else
2940 static int __net_init xfrm_statistics_init(struct net *net)
2941 {
2942 	return 0;
2943 }
2944 
2945 static void xfrm_statistics_fini(struct net *net)
2946 {
2947 }
2948 #endif
2949 
2950 static int __net_init xfrm_policy_init(struct net *net)
2951 {
2952 	unsigned int hmask, sz;
2953 	int dir;
2954 
2955 	if (net_eq(net, &init_net))
2956 		xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2957 					   sizeof(struct xfrm_dst),
2958 					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2959 					   NULL);
2960 
2961 	hmask = 8 - 1;
2962 	sz = (hmask+1) * sizeof(struct hlist_head);
2963 
2964 	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2965 	if (!net->xfrm.policy_byidx)
2966 		goto out_byidx;
2967 	net->xfrm.policy_idx_hmask = hmask;
2968 
2969 	for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2970 		struct xfrm_policy_hash *htab;
2971 
2972 		net->xfrm.policy_count[dir] = 0;
2973 		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2974 
2975 		htab = &net->xfrm.policy_bydst[dir];
2976 		htab->table = xfrm_hash_alloc(sz);
2977 		if (!htab->table)
2978 			goto out_bydst;
2979 		htab->hmask = hmask;
2980 		htab->dbits4 = 32;
2981 		htab->sbits4 = 32;
2982 		htab->dbits6 = 128;
2983 		htab->sbits6 = 128;
2984 	}
2985 	net->xfrm.policy_hthresh.lbits4 = 32;
2986 	net->xfrm.policy_hthresh.rbits4 = 32;
2987 	net->xfrm.policy_hthresh.lbits6 = 128;
2988 	net->xfrm.policy_hthresh.rbits6 = 128;
2989 
2990 	seqlock_init(&net->xfrm.policy_hthresh.lock);
2991 
2992 	INIT_LIST_HEAD(&net->xfrm.policy_all);
2993 	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2994 	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2995 	if (net_eq(net, &init_net))
2996 		register_netdevice_notifier(&xfrm_dev_notifier);
2997 	return 0;
2998 
2999 out_bydst:
3000 	for (dir--; dir >= 0; dir--) {
3001 		struct xfrm_policy_hash *htab;
3002 
3003 		htab = &net->xfrm.policy_bydst[dir];
3004 		xfrm_hash_free(htab->table, sz);
3005 	}
3006 	xfrm_hash_free(net->xfrm.policy_byidx, sz);
3007 out_byidx:
3008 	return -ENOMEM;
3009 }
3010 
3011 static void xfrm_policy_fini(struct net *net)
3012 {
3013 	unsigned int sz;
3014 	int dir;
3015 
3016 	flush_work(&net->xfrm.policy_hash_work);
3017 #ifdef CONFIG_XFRM_SUB_POLICY
3018 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
3019 #endif
3020 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
3021 
3022 	WARN_ON(!list_empty(&net->xfrm.policy_all));
3023 
3024 	for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
3025 		struct xfrm_policy_hash *htab;
3026 
3027 		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
3028 
3029 		htab = &net->xfrm.policy_bydst[dir];
3030 		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
3031 		WARN_ON(!hlist_empty(htab->table));
3032 		xfrm_hash_free(htab->table, sz);
3033 	}
3034 
3035 	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
3036 	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
3037 	xfrm_hash_free(net->xfrm.policy_byidx, sz);
3038 }
3039 
3040 static int __net_init xfrm_net_init(struct net *net)
3041 {
3042 	int rv;
3043 
3044 	rv = xfrm_statistics_init(net);
3045 	if (rv < 0)
3046 		goto out_statistics;
3047 	rv = xfrm_state_init(net);
3048 	if (rv < 0)
3049 		goto out_state;
3050 	rv = xfrm_policy_init(net);
3051 	if (rv < 0)
3052 		goto out_policy;
3053 	xfrm_dst_ops_init(net);
3054 	rv = xfrm_sysctl_init(net);
3055 	if (rv < 0)
3056 		goto out_sysctl;
3057 	rv = flow_cache_init(net);
3058 	if (rv < 0)
3059 		goto out;
3060 
3061 	/* Initialize the per-net locks here */
3062 	spin_lock_init(&net->xfrm.xfrm_state_lock);
3063 	rwlock_init(&net->xfrm.xfrm_policy_lock);
3064 	mutex_init(&net->xfrm.xfrm_cfg_mutex);
3065 
3066 	return 0;
3067 
3068 out:
3069 	xfrm_sysctl_fini(net);
3070 out_sysctl:
3071 	xfrm_policy_fini(net);
3072 out_policy:
3073 	xfrm_state_fini(net);
3074 out_state:
3075 	xfrm_statistics_fini(net);
3076 out_statistics:
3077 	return rv;
3078 }
3079 
3080 static void __net_exit xfrm_net_exit(struct net *net)
3081 {
3082 	flow_cache_fini(net);
3083 	xfrm_sysctl_fini(net);
3084 	xfrm_policy_fini(net);
3085 	xfrm_state_fini(net);
3086 	xfrm_statistics_fini(net);
3087 }
3088 
3089 static struct pernet_operations __net_initdata xfrm_net_ops = {
3090 	.init = xfrm_net_init,
3091 	.exit = xfrm_net_exit,
3092 };
3093 
3094 void __init xfrm_init(void)
3095 {
3096 	register_pernet_subsys(&xfrm_net_ops);
3097 	xfrm_input_init();
3098 }
3099 
3100 #ifdef CONFIG_AUDITSYSCALL
3101 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3102 					 struct audit_buffer *audit_buf)
3103 {
3104 	struct xfrm_sec_ctx *ctx = xp->security;
3105 	struct xfrm_selector *sel = &xp->selector;
3106 
3107 	if (ctx)
3108 		audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3109 				 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3110 
3111 	switch (sel->family) {
3112 	case AF_INET:
3113 		audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3114 		if (sel->prefixlen_s != 32)
3115 			audit_log_format(audit_buf, " src_prefixlen=%d",
3116 					 sel->prefixlen_s);
3117 		audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3118 		if (sel->prefixlen_d != 32)
3119 			audit_log_format(audit_buf, " dst_prefixlen=%d",
3120 					 sel->prefixlen_d);
3121 		break;
3122 	case AF_INET6:
3123 		audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3124 		if (sel->prefixlen_s != 128)
3125 			audit_log_format(audit_buf, " src_prefixlen=%d",
3126 					 sel->prefixlen_s);
3127 		audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3128 		if (sel->prefixlen_d != 128)
3129 			audit_log_format(audit_buf, " dst_prefixlen=%d",
3130 					 sel->prefixlen_d);
3131 		break;
3132 	}
3133 }
3134 
3135 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3136 {
3137 	struct audit_buffer *audit_buf;
3138 
3139 	audit_buf = xfrm_audit_start("SPD-add");
3140 	if (audit_buf == NULL)
3141 		return;
3142 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3143 	audit_log_format(audit_buf, " res=%u", result);
3144 	xfrm_audit_common_policyinfo(xp, audit_buf);
3145 	audit_log_end(audit_buf);
3146 }
3147 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3148 
3149 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3150 			      bool task_valid)
3151 {
3152 	struct audit_buffer *audit_buf;
3153 
3154 	audit_buf = xfrm_audit_start("SPD-delete");
3155 	if (audit_buf == NULL)
3156 		return;
3157 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3158 	audit_log_format(audit_buf, " res=%u", result);
3159 	xfrm_audit_common_policyinfo(xp, audit_buf);
3160 	audit_log_end(audit_buf);
3161 }
3162 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3163 #endif
3164 
3165 #ifdef CONFIG_XFRM_MIGRATE
3166 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3167 					const struct xfrm_selector *sel_tgt)
3168 {
3169 	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3170 		if (sel_tgt->family == sel_cmp->family &&
3171 		    xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3172 				    sel_cmp->family) &&
3173 		    xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3174 				    sel_cmp->family) &&
3175 		    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3176 		    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3177 			return true;
3178 		}
3179 	} else {
3180 		if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3181 			return true;
3182 		}
3183 	}
3184 	return false;
3185 }
3186 
3187 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3188 						    u8 dir, u8 type, struct net *net)
3189 {
3190 	struct xfrm_policy *pol, *ret = NULL;
3191 	struct hlist_head *chain;
3192 	u32 priority = ~0U;
3193 
3194 	read_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME*/
3195 	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3196 	hlist_for_each_entry(pol, chain, bydst) {
3197 		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3198 		    pol->type == type) {
3199 			ret = pol;
3200 			priority = ret->priority;
3201 			break;
3202 		}
3203 	}
3204 	chain = &net->xfrm.policy_inexact[dir];
3205 	hlist_for_each_entry(pol, chain, bydst) {
3206 		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3207 		    pol->type == type &&
3208 		    pol->priority < priority) {
3209 			ret = pol;
3210 			break;
3211 		}
3212 	}
3213 
3214 	if (ret)
3215 		xfrm_pol_hold(ret);
3216 
3217 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
3218 
3219 	return ret;
3220 }
3221 
3222 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3223 {
3224 	int match = 0;
3225 
3226 	if (t->mode == m->mode && t->id.proto == m->proto &&
3227 	    (m->reqid == 0 || t->reqid == m->reqid)) {
3228 		switch (t->mode) {
3229 		case XFRM_MODE_TUNNEL:
3230 		case XFRM_MODE_BEET:
3231 			if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3232 					    m->old_family) &&
3233 			    xfrm_addr_equal(&t->saddr, &m->old_saddr,
3234 					    m->old_family)) {
3235 				match = 1;
3236 			}
3237 			break;
3238 		case XFRM_MODE_TRANSPORT:
3239 			/* in case of transport mode, template does not store
3240 			   any IP addresses, hence we just compare mode and
3241 			   protocol */
3242 			match = 1;
3243 			break;
3244 		default:
3245 			break;
3246 		}
3247 	}
3248 	return match;
3249 }
3250 
3251 /* update endpoint address(es) of template(s) */
3252 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3253 			       struct xfrm_migrate *m, int num_migrate)
3254 {
3255 	struct xfrm_migrate *mp;
3256 	int i, j, n = 0;
3257 
3258 	write_lock_bh(&pol->lock);
3259 	if (unlikely(pol->walk.dead)) {
3260 		/* target policy has been deleted */
3261 		write_unlock_bh(&pol->lock);
3262 		return -ENOENT;
3263 	}
3264 
3265 	for (i = 0; i < pol->xfrm_nr; i++) {
3266 		for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3267 			if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3268 				continue;
3269 			n++;
3270 			if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3271 			    pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3272 				continue;
3273 			/* update endpoints */
3274 			memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3275 			       sizeof(pol->xfrm_vec[i].id.daddr));
3276 			memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3277 			       sizeof(pol->xfrm_vec[i].saddr));
3278 			pol->xfrm_vec[i].encap_family = mp->new_family;
3279 			/* flush bundles */
3280 			atomic_inc(&pol->genid);
3281 		}
3282 	}
3283 
3284 	write_unlock_bh(&pol->lock);
3285 
3286 	if (!n)
3287 		return -ENODATA;
3288 
3289 	return 0;
3290 }
3291 
3292 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3293 {
3294 	int i, j;
3295 
3296 	if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3297 		return -EINVAL;
3298 
3299 	for (i = 0; i < num_migrate; i++) {
3300 		if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3301 				    m[i].old_family) &&
3302 		    xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3303 				    m[i].old_family))
3304 			return -EINVAL;
3305 		if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3306 		    xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3307 			return -EINVAL;
3308 
3309 		/* check if there is any duplicated entry */
3310 		for (j = i + 1; j < num_migrate; j++) {
3311 			if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3312 				    sizeof(m[i].old_daddr)) &&
3313 			    !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3314 				    sizeof(m[i].old_saddr)) &&
3315 			    m[i].proto == m[j].proto &&
3316 			    m[i].mode == m[j].mode &&
3317 			    m[i].reqid == m[j].reqid &&
3318 			    m[i].old_family == m[j].old_family)
3319 				return -EINVAL;
3320 		}
3321 	}
3322 
3323 	return 0;
3324 }
3325 
3326 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3327 		 struct xfrm_migrate *m, int num_migrate,
3328 		 struct xfrm_kmaddress *k, struct net *net)
3329 {
3330 	int i, err, nx_cur = 0, nx_new = 0;
3331 	struct xfrm_policy *pol = NULL;
3332 	struct xfrm_state *x, *xc;
3333 	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3334 	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3335 	struct xfrm_migrate *mp;
3336 
3337 	if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3338 		goto out;
3339 
3340 	/* Stage 1 - find policy */
3341 	if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3342 		err = -ENOENT;
3343 		goto out;
3344 	}
3345 
3346 	/* Stage 2 - find and update state(s) */
3347 	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3348 		if ((x = xfrm_migrate_state_find(mp, net))) {
3349 			x_cur[nx_cur] = x;
3350 			nx_cur++;
3351 			if ((xc = xfrm_state_migrate(x, mp))) {
3352 				x_new[nx_new] = xc;
3353 				nx_new++;
3354 			} else {
3355 				err = -ENODATA;
3356 				goto restore_state;
3357 			}
3358 		}
3359 	}
3360 
3361 	/* Stage 3 - update policy */
3362 	if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3363 		goto restore_state;
3364 
3365 	/* Stage 4 - delete old state(s) */
3366 	if (nx_cur) {
3367 		xfrm_states_put(x_cur, nx_cur);
3368 		xfrm_states_delete(x_cur, nx_cur);
3369 	}
3370 
3371 	/* Stage 5 - announce */
3372 	km_migrate(sel, dir, type, m, num_migrate, k);
3373 
3374 	xfrm_pol_put(pol);
3375 
3376 	return 0;
3377 out:
3378 	return err;
3379 
3380 restore_state:
3381 	if (pol)
3382 		xfrm_pol_put(pol);
3383 	if (nx_cur)
3384 		xfrm_states_put(x_cur, nx_cur);
3385 	if (nx_new)
3386 		xfrm_states_delete(x_new, nx_new);
3387 
3388 	return err;
3389 }
3390 EXPORT_SYMBOL(xfrm_migrate);
3391 #endif
3392