xref: /linux/net/xfrm/xfrm_policy.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /*
2  * xfrm_policy.c
3  *
4  * Changes:
5  *	Mitsuru KANDA @USAGI
6  * 	Kazunori MIYAZAWA @USAGI
7  * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8  * 		IPv6 support
9  * 	Kazunori MIYAZAWA @USAGI
10  * 	YOSHIFUJI Hideaki
11  * 		Split up af-specific portion
12  *	Derek Atkins <derek@ihtfp.com>		Add the post_input processor
13  *
14  */
15 
16 #include <linux/err.h>
17 #include <linux/slab.h>
18 #include <linux/kmod.h>
19 #include <linux/list.h>
20 #include <linux/spinlock.h>
21 #include <linux/workqueue.h>
22 #include <linux/notifier.h>
23 #include <linux/netdevice.h>
24 #include <linux/netfilter.h>
25 #include <linux/module.h>
26 #include <linux/cache.h>
27 #include <linux/audit.h>
28 #include <net/dst.h>
29 #include <net/flow.h>
30 #include <net/xfrm.h>
31 #include <net/ip.h>
32 #ifdef CONFIG_XFRM_STATISTICS
33 #include <net/snmp.h>
34 #endif
35 
36 #include "xfrm_hash.h"
37 
38 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
39 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
40 #define XFRM_MAX_QUEUE_LEN	100
41 
42 struct xfrm_flo {
43 	struct dst_entry *dst_orig;
44 	u8 flags;
45 };
46 
47 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
48 static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
49 						__read_mostly;
50 
51 static struct kmem_cache *xfrm_dst_cache __read_mostly;
52 
53 static void xfrm_init_pmtu(struct dst_entry *dst);
54 static int stale_bundle(struct dst_entry *dst);
55 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
56 static void xfrm_policy_queue_process(unsigned long arg);
57 
58 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
59 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
60 						int dir);
61 
62 static inline bool
63 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
64 {
65 	const struct flowi4 *fl4 = &fl->u.ip4;
66 
67 	return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
68 		addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
69 		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
70 		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
71 		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
72 		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
73 }
74 
75 static inline bool
76 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
77 {
78 	const struct flowi6 *fl6 = &fl->u.ip6;
79 
80 	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
81 		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
82 		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
83 		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
84 		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
85 		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
86 }
87 
88 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
89 			 unsigned short family)
90 {
91 	switch (family) {
92 	case AF_INET:
93 		return __xfrm4_selector_match(sel, fl);
94 	case AF_INET6:
95 		return __xfrm6_selector_match(sel, fl);
96 	}
97 	return false;
98 }
99 
100 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
101 {
102 	struct xfrm_policy_afinfo *afinfo;
103 
104 	if (unlikely(family >= NPROTO))
105 		return NULL;
106 	rcu_read_lock();
107 	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
108 	if (unlikely(!afinfo))
109 		rcu_read_unlock();
110 	return afinfo;
111 }
112 
113 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
114 {
115 	rcu_read_unlock();
116 }
117 
118 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
119 						  const xfrm_address_t *saddr,
120 						  const xfrm_address_t *daddr,
121 						  int family)
122 {
123 	struct xfrm_policy_afinfo *afinfo;
124 	struct dst_entry *dst;
125 
126 	afinfo = xfrm_policy_get_afinfo(family);
127 	if (unlikely(afinfo == NULL))
128 		return ERR_PTR(-EAFNOSUPPORT);
129 
130 	dst = afinfo->dst_lookup(net, tos, saddr, daddr);
131 
132 	xfrm_policy_put_afinfo(afinfo);
133 
134 	return dst;
135 }
136 
137 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
138 						xfrm_address_t *prev_saddr,
139 						xfrm_address_t *prev_daddr,
140 						int family)
141 {
142 	struct net *net = xs_net(x);
143 	xfrm_address_t *saddr = &x->props.saddr;
144 	xfrm_address_t *daddr = &x->id.daddr;
145 	struct dst_entry *dst;
146 
147 	if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
148 		saddr = x->coaddr;
149 		daddr = prev_daddr;
150 	}
151 	if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
152 		saddr = prev_saddr;
153 		daddr = x->coaddr;
154 	}
155 
156 	dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
157 
158 	if (!IS_ERR(dst)) {
159 		if (prev_saddr != saddr)
160 			memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
161 		if (prev_daddr != daddr)
162 			memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
163 	}
164 
165 	return dst;
166 }
167 
168 static inline unsigned long make_jiffies(long secs)
169 {
170 	if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
171 		return MAX_SCHEDULE_TIMEOUT-1;
172 	else
173 		return secs*HZ;
174 }
175 
176 static void xfrm_policy_timer(unsigned long data)
177 {
178 	struct xfrm_policy *xp = (struct xfrm_policy *)data;
179 	unsigned long now = get_seconds();
180 	long next = LONG_MAX;
181 	int warn = 0;
182 	int dir;
183 
184 	read_lock(&xp->lock);
185 
186 	if (unlikely(xp->walk.dead))
187 		goto out;
188 
189 	dir = xfrm_policy_id2dir(xp->index);
190 
191 	if (xp->lft.hard_add_expires_seconds) {
192 		long tmo = xp->lft.hard_add_expires_seconds +
193 			xp->curlft.add_time - now;
194 		if (tmo <= 0)
195 			goto expired;
196 		if (tmo < next)
197 			next = tmo;
198 	}
199 	if (xp->lft.hard_use_expires_seconds) {
200 		long tmo = xp->lft.hard_use_expires_seconds +
201 			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
202 		if (tmo <= 0)
203 			goto expired;
204 		if (tmo < next)
205 			next = tmo;
206 	}
207 	if (xp->lft.soft_add_expires_seconds) {
208 		long tmo = xp->lft.soft_add_expires_seconds +
209 			xp->curlft.add_time - now;
210 		if (tmo <= 0) {
211 			warn = 1;
212 			tmo = XFRM_KM_TIMEOUT;
213 		}
214 		if (tmo < next)
215 			next = tmo;
216 	}
217 	if (xp->lft.soft_use_expires_seconds) {
218 		long tmo = xp->lft.soft_use_expires_seconds +
219 			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
220 		if (tmo <= 0) {
221 			warn = 1;
222 			tmo = XFRM_KM_TIMEOUT;
223 		}
224 		if (tmo < next)
225 			next = tmo;
226 	}
227 
228 	if (warn)
229 		km_policy_expired(xp, dir, 0, 0);
230 	if (next != LONG_MAX &&
231 	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
232 		xfrm_pol_hold(xp);
233 
234 out:
235 	read_unlock(&xp->lock);
236 	xfrm_pol_put(xp);
237 	return;
238 
239 expired:
240 	read_unlock(&xp->lock);
241 	if (!xfrm_policy_delete(xp, dir))
242 		km_policy_expired(xp, dir, 1, 0);
243 	xfrm_pol_put(xp);
244 }
245 
246 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
247 {
248 	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
249 
250 	if (unlikely(pol->walk.dead))
251 		flo = NULL;
252 	else
253 		xfrm_pol_hold(pol);
254 
255 	return flo;
256 }
257 
258 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
259 {
260 	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
261 
262 	return !pol->walk.dead;
263 }
264 
265 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
266 {
267 	xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
268 }
269 
270 static const struct flow_cache_ops xfrm_policy_fc_ops = {
271 	.get = xfrm_policy_flo_get,
272 	.check = xfrm_policy_flo_check,
273 	.delete = xfrm_policy_flo_delete,
274 };
275 
276 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
277  * SPD calls.
278  */
279 
280 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
281 {
282 	struct xfrm_policy *policy;
283 
284 	policy = kzalloc(sizeof(struct xfrm_policy), gfp);
285 
286 	if (policy) {
287 		write_pnet(&policy->xp_net, net);
288 		INIT_LIST_HEAD(&policy->walk.all);
289 		INIT_HLIST_NODE(&policy->bydst);
290 		INIT_HLIST_NODE(&policy->byidx);
291 		rwlock_init(&policy->lock);
292 		atomic_set(&policy->refcnt, 1);
293 		skb_queue_head_init(&policy->polq.hold_queue);
294 		setup_timer(&policy->timer, xfrm_policy_timer,
295 				(unsigned long)policy);
296 		setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
297 			    (unsigned long)policy);
298 		policy->flo.ops = &xfrm_policy_fc_ops;
299 	}
300 	return policy;
301 }
302 EXPORT_SYMBOL(xfrm_policy_alloc);
303 
304 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
305 
306 void xfrm_policy_destroy(struct xfrm_policy *policy)
307 {
308 	BUG_ON(!policy->walk.dead);
309 
310 	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
311 		BUG();
312 
313 	security_xfrm_policy_free(policy->security);
314 	kfree(policy);
315 }
316 EXPORT_SYMBOL(xfrm_policy_destroy);
317 
318 /* Rule must be locked. Release descentant resources, announce
319  * entry dead. The rule must be unlinked from lists to the moment.
320  */
321 
322 static void xfrm_policy_kill(struct xfrm_policy *policy)
323 {
324 	policy->walk.dead = 1;
325 
326 	atomic_inc(&policy->genid);
327 
328 	if (del_timer(&policy->polq.hold_timer))
329 		xfrm_pol_put(policy);
330 	skb_queue_purge(&policy->polq.hold_queue);
331 
332 	if (del_timer(&policy->timer))
333 		xfrm_pol_put(policy);
334 
335 	xfrm_pol_put(policy);
336 }
337 
338 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
339 
340 static inline unsigned int idx_hash(struct net *net, u32 index)
341 {
342 	return __idx_hash(index, net->xfrm.policy_idx_hmask);
343 }
344 
345 /* calculate policy hash thresholds */
346 static void __get_hash_thresh(struct net *net,
347 			      unsigned short family, int dir,
348 			      u8 *dbits, u8 *sbits)
349 {
350 	switch (family) {
351 	case AF_INET:
352 		*dbits = net->xfrm.policy_bydst[dir].dbits4;
353 		*sbits = net->xfrm.policy_bydst[dir].sbits4;
354 		break;
355 
356 	case AF_INET6:
357 		*dbits = net->xfrm.policy_bydst[dir].dbits6;
358 		*sbits = net->xfrm.policy_bydst[dir].sbits6;
359 		break;
360 
361 	default:
362 		*dbits = 0;
363 		*sbits = 0;
364 	}
365 }
366 
367 static struct hlist_head *policy_hash_bysel(struct net *net,
368 					    const struct xfrm_selector *sel,
369 					    unsigned short family, int dir)
370 {
371 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
372 	unsigned int hash;
373 	u8 dbits;
374 	u8 sbits;
375 
376 	__get_hash_thresh(net, family, dir, &dbits, &sbits);
377 	hash = __sel_hash(sel, family, hmask, dbits, sbits);
378 
379 	return (hash == hmask + 1 ?
380 		&net->xfrm.policy_inexact[dir] :
381 		net->xfrm.policy_bydst[dir].table + hash);
382 }
383 
384 static struct hlist_head *policy_hash_direct(struct net *net,
385 					     const xfrm_address_t *daddr,
386 					     const xfrm_address_t *saddr,
387 					     unsigned short family, int dir)
388 {
389 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
390 	unsigned int hash;
391 	u8 dbits;
392 	u8 sbits;
393 
394 	__get_hash_thresh(net, family, dir, &dbits, &sbits);
395 	hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
396 
397 	return net->xfrm.policy_bydst[dir].table + hash;
398 }
399 
400 static void xfrm_dst_hash_transfer(struct net *net,
401 				   struct hlist_head *list,
402 				   struct hlist_head *ndsttable,
403 				   unsigned int nhashmask,
404 				   int dir)
405 {
406 	struct hlist_node *tmp, *entry0 = NULL;
407 	struct xfrm_policy *pol;
408 	unsigned int h0 = 0;
409 	u8 dbits;
410 	u8 sbits;
411 
412 redo:
413 	hlist_for_each_entry_safe(pol, tmp, list, bydst) {
414 		unsigned int h;
415 
416 		__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
417 		h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
418 				pol->family, nhashmask, dbits, sbits);
419 		if (!entry0) {
420 			hlist_del(&pol->bydst);
421 			hlist_add_head(&pol->bydst, ndsttable+h);
422 			h0 = h;
423 		} else {
424 			if (h != h0)
425 				continue;
426 			hlist_del(&pol->bydst);
427 			hlist_add_behind(&pol->bydst, entry0);
428 		}
429 		entry0 = &pol->bydst;
430 	}
431 	if (!hlist_empty(list)) {
432 		entry0 = NULL;
433 		goto redo;
434 	}
435 }
436 
437 static void xfrm_idx_hash_transfer(struct hlist_head *list,
438 				   struct hlist_head *nidxtable,
439 				   unsigned int nhashmask)
440 {
441 	struct hlist_node *tmp;
442 	struct xfrm_policy *pol;
443 
444 	hlist_for_each_entry_safe(pol, tmp, list, byidx) {
445 		unsigned int h;
446 
447 		h = __idx_hash(pol->index, nhashmask);
448 		hlist_add_head(&pol->byidx, nidxtable+h);
449 	}
450 }
451 
452 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
453 {
454 	return ((old_hmask + 1) << 1) - 1;
455 }
456 
457 static void xfrm_bydst_resize(struct net *net, int dir)
458 {
459 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
460 	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
461 	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
462 	struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
463 	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
464 	int i;
465 
466 	if (!ndst)
467 		return;
468 
469 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
470 
471 	for (i = hmask; i >= 0; i--)
472 		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
473 
474 	net->xfrm.policy_bydst[dir].table = ndst;
475 	net->xfrm.policy_bydst[dir].hmask = nhashmask;
476 
477 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
478 
479 	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
480 }
481 
482 static void xfrm_byidx_resize(struct net *net, int total)
483 {
484 	unsigned int hmask = net->xfrm.policy_idx_hmask;
485 	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
486 	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
487 	struct hlist_head *oidx = net->xfrm.policy_byidx;
488 	struct hlist_head *nidx = xfrm_hash_alloc(nsize);
489 	int i;
490 
491 	if (!nidx)
492 		return;
493 
494 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
495 
496 	for (i = hmask; i >= 0; i--)
497 		xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
498 
499 	net->xfrm.policy_byidx = nidx;
500 	net->xfrm.policy_idx_hmask = nhashmask;
501 
502 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
503 
504 	xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
505 }
506 
507 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
508 {
509 	unsigned int cnt = net->xfrm.policy_count[dir];
510 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
511 
512 	if (total)
513 		*total += cnt;
514 
515 	if ((hmask + 1) < xfrm_policy_hashmax &&
516 	    cnt > hmask)
517 		return 1;
518 
519 	return 0;
520 }
521 
522 static inline int xfrm_byidx_should_resize(struct net *net, int total)
523 {
524 	unsigned int hmask = net->xfrm.policy_idx_hmask;
525 
526 	if ((hmask + 1) < xfrm_policy_hashmax &&
527 	    total > hmask)
528 		return 1;
529 
530 	return 0;
531 }
532 
533 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
534 {
535 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
536 	si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
537 	si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
538 	si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
539 	si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
540 	si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
541 	si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
542 	si->spdhcnt = net->xfrm.policy_idx_hmask;
543 	si->spdhmcnt = xfrm_policy_hashmax;
544 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
545 }
546 EXPORT_SYMBOL(xfrm_spd_getinfo);
547 
548 static DEFINE_MUTEX(hash_resize_mutex);
549 static void xfrm_hash_resize(struct work_struct *work)
550 {
551 	struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
552 	int dir, total;
553 
554 	mutex_lock(&hash_resize_mutex);
555 
556 	total = 0;
557 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
558 		if (xfrm_bydst_should_resize(net, dir, &total))
559 			xfrm_bydst_resize(net, dir);
560 	}
561 	if (xfrm_byidx_should_resize(net, total))
562 		xfrm_byidx_resize(net, total);
563 
564 	mutex_unlock(&hash_resize_mutex);
565 }
566 
567 static void xfrm_hash_rebuild(struct work_struct *work)
568 {
569 	struct net *net = container_of(work, struct net,
570 				       xfrm.policy_hthresh.work);
571 	unsigned int hmask;
572 	struct xfrm_policy *pol;
573 	struct xfrm_policy *policy;
574 	struct hlist_head *chain;
575 	struct hlist_head *odst;
576 	struct hlist_node *newpos;
577 	int i;
578 	int dir;
579 	unsigned seq;
580 	u8 lbits4, rbits4, lbits6, rbits6;
581 
582 	mutex_lock(&hash_resize_mutex);
583 
584 	/* read selector prefixlen thresholds */
585 	do {
586 		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
587 
588 		lbits4 = net->xfrm.policy_hthresh.lbits4;
589 		rbits4 = net->xfrm.policy_hthresh.rbits4;
590 		lbits6 = net->xfrm.policy_hthresh.lbits6;
591 		rbits6 = net->xfrm.policy_hthresh.rbits6;
592 	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
593 
594 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
595 
596 	/* reset the bydst and inexact table in all directions */
597 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
598 		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
599 		hmask = net->xfrm.policy_bydst[dir].hmask;
600 		odst = net->xfrm.policy_bydst[dir].table;
601 		for (i = hmask; i >= 0; i--)
602 			INIT_HLIST_HEAD(odst + i);
603 		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
604 			/* dir out => dst = remote, src = local */
605 			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
606 			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
607 			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
608 			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
609 		} else {
610 			/* dir in/fwd => dst = local, src = remote */
611 			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
612 			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
613 			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
614 			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
615 		}
616 	}
617 
618 	/* re-insert all policies by order of creation */
619 	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
620 		newpos = NULL;
621 		chain = policy_hash_bysel(net, &policy->selector,
622 					  policy->family,
623 					  xfrm_policy_id2dir(policy->index));
624 		hlist_for_each_entry(pol, chain, bydst) {
625 			if (policy->priority >= pol->priority)
626 				newpos = &pol->bydst;
627 			else
628 				break;
629 		}
630 		if (newpos)
631 			hlist_add_behind(&policy->bydst, newpos);
632 		else
633 			hlist_add_head(&policy->bydst, chain);
634 	}
635 
636 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
637 
638 	mutex_unlock(&hash_resize_mutex);
639 }
640 
641 void xfrm_policy_hash_rebuild(struct net *net)
642 {
643 	schedule_work(&net->xfrm.policy_hthresh.work);
644 }
645 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
646 
647 /* Generate new index... KAME seems to generate them ordered by cost
648  * of an absolute inpredictability of ordering of rules. This will not pass. */
649 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
650 {
651 	static u32 idx_generator;
652 
653 	for (;;) {
654 		struct hlist_head *list;
655 		struct xfrm_policy *p;
656 		u32 idx;
657 		int found;
658 
659 		if (!index) {
660 			idx = (idx_generator | dir);
661 			idx_generator += 8;
662 		} else {
663 			idx = index;
664 			index = 0;
665 		}
666 
667 		if (idx == 0)
668 			idx = 8;
669 		list = net->xfrm.policy_byidx + idx_hash(net, idx);
670 		found = 0;
671 		hlist_for_each_entry(p, list, byidx) {
672 			if (p->index == idx) {
673 				found = 1;
674 				break;
675 			}
676 		}
677 		if (!found)
678 			return idx;
679 	}
680 }
681 
682 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
683 {
684 	u32 *p1 = (u32 *) s1;
685 	u32 *p2 = (u32 *) s2;
686 	int len = sizeof(struct xfrm_selector) / sizeof(u32);
687 	int i;
688 
689 	for (i = 0; i < len; i++) {
690 		if (p1[i] != p2[i])
691 			return 1;
692 	}
693 
694 	return 0;
695 }
696 
697 static void xfrm_policy_requeue(struct xfrm_policy *old,
698 				struct xfrm_policy *new)
699 {
700 	struct xfrm_policy_queue *pq = &old->polq;
701 	struct sk_buff_head list;
702 
703 	if (skb_queue_empty(&pq->hold_queue))
704 		return;
705 
706 	__skb_queue_head_init(&list);
707 
708 	spin_lock_bh(&pq->hold_queue.lock);
709 	skb_queue_splice_init(&pq->hold_queue, &list);
710 	if (del_timer(&pq->hold_timer))
711 		xfrm_pol_put(old);
712 	spin_unlock_bh(&pq->hold_queue.lock);
713 
714 	pq = &new->polq;
715 
716 	spin_lock_bh(&pq->hold_queue.lock);
717 	skb_queue_splice(&list, &pq->hold_queue);
718 	pq->timeout = XFRM_QUEUE_TMO_MIN;
719 	if (!mod_timer(&pq->hold_timer, jiffies))
720 		xfrm_pol_hold(new);
721 	spin_unlock_bh(&pq->hold_queue.lock);
722 }
723 
724 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
725 				   struct xfrm_policy *pol)
726 {
727 	u32 mark = policy->mark.v & policy->mark.m;
728 
729 	if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
730 		return true;
731 
732 	if ((mark & pol->mark.m) == pol->mark.v &&
733 	    policy->priority == pol->priority)
734 		return true;
735 
736 	return false;
737 }
738 
739 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
740 {
741 	struct net *net = xp_net(policy);
742 	struct xfrm_policy *pol;
743 	struct xfrm_policy *delpol;
744 	struct hlist_head *chain;
745 	struct hlist_node *newpos;
746 
747 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
748 	chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
749 	delpol = NULL;
750 	newpos = NULL;
751 	hlist_for_each_entry(pol, chain, bydst) {
752 		if (pol->type == policy->type &&
753 		    !selector_cmp(&pol->selector, &policy->selector) &&
754 		    xfrm_policy_mark_match(policy, pol) &&
755 		    xfrm_sec_ctx_match(pol->security, policy->security) &&
756 		    !WARN_ON(delpol)) {
757 			if (excl) {
758 				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
759 				return -EEXIST;
760 			}
761 			delpol = pol;
762 			if (policy->priority > pol->priority)
763 				continue;
764 		} else if (policy->priority >= pol->priority) {
765 			newpos = &pol->bydst;
766 			continue;
767 		}
768 		if (delpol)
769 			break;
770 	}
771 	if (newpos)
772 		hlist_add_behind(&policy->bydst, newpos);
773 	else
774 		hlist_add_head(&policy->bydst, chain);
775 	__xfrm_policy_link(policy, dir);
776 	atomic_inc(&net->xfrm.flow_cache_genid);
777 
778 	/* After previous checking, family can either be AF_INET or AF_INET6 */
779 	if (policy->family == AF_INET)
780 		rt_genid_bump_ipv4(net);
781 	else
782 		rt_genid_bump_ipv6(net);
783 
784 	if (delpol) {
785 		xfrm_policy_requeue(delpol, policy);
786 		__xfrm_policy_unlink(delpol, dir);
787 	}
788 	policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
789 	hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
790 	policy->curlft.add_time = get_seconds();
791 	policy->curlft.use_time = 0;
792 	if (!mod_timer(&policy->timer, jiffies + HZ))
793 		xfrm_pol_hold(policy);
794 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
795 
796 	if (delpol)
797 		xfrm_policy_kill(delpol);
798 	else if (xfrm_bydst_should_resize(net, dir, NULL))
799 		schedule_work(&net->xfrm.policy_hash_work);
800 
801 	return 0;
802 }
803 EXPORT_SYMBOL(xfrm_policy_insert);
804 
805 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
806 					  int dir, struct xfrm_selector *sel,
807 					  struct xfrm_sec_ctx *ctx, int delete,
808 					  int *err)
809 {
810 	struct xfrm_policy *pol, *ret;
811 	struct hlist_head *chain;
812 
813 	*err = 0;
814 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
815 	chain = policy_hash_bysel(net, sel, sel->family, dir);
816 	ret = NULL;
817 	hlist_for_each_entry(pol, chain, bydst) {
818 		if (pol->type == type &&
819 		    (mark & pol->mark.m) == pol->mark.v &&
820 		    !selector_cmp(sel, &pol->selector) &&
821 		    xfrm_sec_ctx_match(ctx, pol->security)) {
822 			xfrm_pol_hold(pol);
823 			if (delete) {
824 				*err = security_xfrm_policy_delete(
825 								pol->security);
826 				if (*err) {
827 					write_unlock_bh(&net->xfrm.xfrm_policy_lock);
828 					return pol;
829 				}
830 				__xfrm_policy_unlink(pol, dir);
831 			}
832 			ret = pol;
833 			break;
834 		}
835 	}
836 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
837 
838 	if (ret && delete)
839 		xfrm_policy_kill(ret);
840 	return ret;
841 }
842 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
843 
844 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
845 				     int dir, u32 id, int delete, int *err)
846 {
847 	struct xfrm_policy *pol, *ret;
848 	struct hlist_head *chain;
849 
850 	*err = -ENOENT;
851 	if (xfrm_policy_id2dir(id) != dir)
852 		return NULL;
853 
854 	*err = 0;
855 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
856 	chain = net->xfrm.policy_byidx + idx_hash(net, id);
857 	ret = NULL;
858 	hlist_for_each_entry(pol, chain, byidx) {
859 		if (pol->type == type && pol->index == id &&
860 		    (mark & pol->mark.m) == pol->mark.v) {
861 			xfrm_pol_hold(pol);
862 			if (delete) {
863 				*err = security_xfrm_policy_delete(
864 								pol->security);
865 				if (*err) {
866 					write_unlock_bh(&net->xfrm.xfrm_policy_lock);
867 					return pol;
868 				}
869 				__xfrm_policy_unlink(pol, dir);
870 			}
871 			ret = pol;
872 			break;
873 		}
874 	}
875 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
876 
877 	if (ret && delete)
878 		xfrm_policy_kill(ret);
879 	return ret;
880 }
881 EXPORT_SYMBOL(xfrm_policy_byid);
882 
883 #ifdef CONFIG_SECURITY_NETWORK_XFRM
884 static inline int
885 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
886 {
887 	int dir, err = 0;
888 
889 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
890 		struct xfrm_policy *pol;
891 		int i;
892 
893 		hlist_for_each_entry(pol,
894 				     &net->xfrm.policy_inexact[dir], bydst) {
895 			if (pol->type != type)
896 				continue;
897 			err = security_xfrm_policy_delete(pol->security);
898 			if (err) {
899 				xfrm_audit_policy_delete(pol, 0, task_valid);
900 				return err;
901 			}
902 		}
903 		for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
904 			hlist_for_each_entry(pol,
905 					     net->xfrm.policy_bydst[dir].table + i,
906 					     bydst) {
907 				if (pol->type != type)
908 					continue;
909 				err = security_xfrm_policy_delete(
910 								pol->security);
911 				if (err) {
912 					xfrm_audit_policy_delete(pol, 0,
913 								 task_valid);
914 					return err;
915 				}
916 			}
917 		}
918 	}
919 	return err;
920 }
921 #else
922 static inline int
923 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
924 {
925 	return 0;
926 }
927 #endif
928 
929 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
930 {
931 	int dir, err = 0, cnt = 0;
932 
933 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
934 
935 	err = xfrm_policy_flush_secctx_check(net, type, task_valid);
936 	if (err)
937 		goto out;
938 
939 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
940 		struct xfrm_policy *pol;
941 		int i;
942 
943 	again1:
944 		hlist_for_each_entry(pol,
945 				     &net->xfrm.policy_inexact[dir], bydst) {
946 			if (pol->type != type)
947 				continue;
948 			__xfrm_policy_unlink(pol, dir);
949 			write_unlock_bh(&net->xfrm.xfrm_policy_lock);
950 			cnt++;
951 
952 			xfrm_audit_policy_delete(pol, 1, task_valid);
953 
954 			xfrm_policy_kill(pol);
955 
956 			write_lock_bh(&net->xfrm.xfrm_policy_lock);
957 			goto again1;
958 		}
959 
960 		for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
961 	again2:
962 			hlist_for_each_entry(pol,
963 					     net->xfrm.policy_bydst[dir].table + i,
964 					     bydst) {
965 				if (pol->type != type)
966 					continue;
967 				__xfrm_policy_unlink(pol, dir);
968 				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
969 				cnt++;
970 
971 				xfrm_audit_policy_delete(pol, 1, task_valid);
972 				xfrm_policy_kill(pol);
973 
974 				write_lock_bh(&net->xfrm.xfrm_policy_lock);
975 				goto again2;
976 			}
977 		}
978 
979 	}
980 	if (!cnt)
981 		err = -ESRCH;
982 out:
983 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
984 	return err;
985 }
986 EXPORT_SYMBOL(xfrm_policy_flush);
987 
988 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
989 		     int (*func)(struct xfrm_policy *, int, int, void*),
990 		     void *data)
991 {
992 	struct xfrm_policy *pol;
993 	struct xfrm_policy_walk_entry *x;
994 	int error = 0;
995 
996 	if (walk->type >= XFRM_POLICY_TYPE_MAX &&
997 	    walk->type != XFRM_POLICY_TYPE_ANY)
998 		return -EINVAL;
999 
1000 	if (list_empty(&walk->walk.all) && walk->seq != 0)
1001 		return 0;
1002 
1003 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1004 	if (list_empty(&walk->walk.all))
1005 		x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1006 	else
1007 		x = list_first_entry(&walk->walk.all,
1008 				     struct xfrm_policy_walk_entry, all);
1009 
1010 	list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1011 		if (x->dead)
1012 			continue;
1013 		pol = container_of(x, struct xfrm_policy, walk);
1014 		if (walk->type != XFRM_POLICY_TYPE_ANY &&
1015 		    walk->type != pol->type)
1016 			continue;
1017 		error = func(pol, xfrm_policy_id2dir(pol->index),
1018 			     walk->seq, data);
1019 		if (error) {
1020 			list_move_tail(&walk->walk.all, &x->all);
1021 			goto out;
1022 		}
1023 		walk->seq++;
1024 	}
1025 	if (walk->seq == 0) {
1026 		error = -ENOENT;
1027 		goto out;
1028 	}
1029 	list_del_init(&walk->walk.all);
1030 out:
1031 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1032 	return error;
1033 }
1034 EXPORT_SYMBOL(xfrm_policy_walk);
1035 
1036 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1037 {
1038 	INIT_LIST_HEAD(&walk->walk.all);
1039 	walk->walk.dead = 1;
1040 	walk->type = type;
1041 	walk->seq = 0;
1042 }
1043 EXPORT_SYMBOL(xfrm_policy_walk_init);
1044 
1045 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1046 {
1047 	if (list_empty(&walk->walk.all))
1048 		return;
1049 
1050 	write_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1051 	list_del(&walk->walk.all);
1052 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1053 }
1054 EXPORT_SYMBOL(xfrm_policy_walk_done);
1055 
1056 /*
1057  * Find policy to apply to this flow.
1058  *
1059  * Returns 0 if policy found, else an -errno.
1060  */
1061 static int xfrm_policy_match(const struct xfrm_policy *pol,
1062 			     const struct flowi *fl,
1063 			     u8 type, u16 family, int dir)
1064 {
1065 	const struct xfrm_selector *sel = &pol->selector;
1066 	int ret = -ESRCH;
1067 	bool match;
1068 
1069 	if (pol->family != family ||
1070 	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1071 	    pol->type != type)
1072 		return ret;
1073 
1074 	match = xfrm_selector_match(sel, fl, family);
1075 	if (match)
1076 		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1077 						  dir);
1078 
1079 	return ret;
1080 }
1081 
1082 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1083 						     const struct flowi *fl,
1084 						     u16 family, u8 dir)
1085 {
1086 	int err;
1087 	struct xfrm_policy *pol, *ret;
1088 	const xfrm_address_t *daddr, *saddr;
1089 	struct hlist_head *chain;
1090 	u32 priority = ~0U;
1091 
1092 	daddr = xfrm_flowi_daddr(fl, family);
1093 	saddr = xfrm_flowi_saddr(fl, family);
1094 	if (unlikely(!daddr || !saddr))
1095 		return NULL;
1096 
1097 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
1098 	chain = policy_hash_direct(net, daddr, saddr, family, dir);
1099 	ret = NULL;
1100 	hlist_for_each_entry(pol, chain, bydst) {
1101 		err = xfrm_policy_match(pol, fl, type, family, dir);
1102 		if (err) {
1103 			if (err == -ESRCH)
1104 				continue;
1105 			else {
1106 				ret = ERR_PTR(err);
1107 				goto fail;
1108 			}
1109 		} else {
1110 			ret = pol;
1111 			priority = ret->priority;
1112 			break;
1113 		}
1114 	}
1115 	chain = &net->xfrm.policy_inexact[dir];
1116 	hlist_for_each_entry(pol, chain, bydst) {
1117 		if ((pol->priority >= priority) && ret)
1118 			break;
1119 
1120 		err = xfrm_policy_match(pol, fl, type, family, dir);
1121 		if (err) {
1122 			if (err == -ESRCH)
1123 				continue;
1124 			else {
1125 				ret = ERR_PTR(err);
1126 				goto fail;
1127 			}
1128 		} else {
1129 			ret = pol;
1130 			break;
1131 		}
1132 	}
1133 
1134 	xfrm_pol_hold(ret);
1135 fail:
1136 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
1137 
1138 	return ret;
1139 }
1140 
1141 static struct xfrm_policy *
1142 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1143 {
1144 #ifdef CONFIG_XFRM_SUB_POLICY
1145 	struct xfrm_policy *pol;
1146 
1147 	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1148 	if (pol != NULL)
1149 		return pol;
1150 #endif
1151 	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1152 }
1153 
1154 static int flow_to_policy_dir(int dir)
1155 {
1156 	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1157 	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1158 	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
1159 		return dir;
1160 
1161 	switch (dir) {
1162 	default:
1163 	case FLOW_DIR_IN:
1164 		return XFRM_POLICY_IN;
1165 	case FLOW_DIR_OUT:
1166 		return XFRM_POLICY_OUT;
1167 	case FLOW_DIR_FWD:
1168 		return XFRM_POLICY_FWD;
1169 	}
1170 }
1171 
1172 static struct flow_cache_object *
1173 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1174 		   u8 dir, struct flow_cache_object *old_obj, void *ctx)
1175 {
1176 	struct xfrm_policy *pol;
1177 
1178 	if (old_obj)
1179 		xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1180 
1181 	pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
1182 	if (IS_ERR_OR_NULL(pol))
1183 		return ERR_CAST(pol);
1184 
1185 	/* Resolver returns two references:
1186 	 * one for cache and one for caller of flow_cache_lookup() */
1187 	xfrm_pol_hold(pol);
1188 
1189 	return &pol->flo;
1190 }
1191 
1192 static inline int policy_to_flow_dir(int dir)
1193 {
1194 	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1195 	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1196 	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
1197 		return dir;
1198 	switch (dir) {
1199 	default:
1200 	case XFRM_POLICY_IN:
1201 		return FLOW_DIR_IN;
1202 	case XFRM_POLICY_OUT:
1203 		return FLOW_DIR_OUT;
1204 	case XFRM_POLICY_FWD:
1205 		return FLOW_DIR_FWD;
1206 	}
1207 }
1208 
1209 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
1210 						 const struct flowi *fl)
1211 {
1212 	struct xfrm_policy *pol;
1213 	struct net *net = sock_net(sk);
1214 
1215 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
1216 	if ((pol = sk->sk_policy[dir]) != NULL) {
1217 		bool match = xfrm_selector_match(&pol->selector, fl,
1218 						 sk->sk_family);
1219 		int err = 0;
1220 
1221 		if (match) {
1222 			if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1223 				pol = NULL;
1224 				goto out;
1225 			}
1226 			err = security_xfrm_policy_lookup(pol->security,
1227 						      fl->flowi_secid,
1228 						      policy_to_flow_dir(dir));
1229 			if (!err)
1230 				xfrm_pol_hold(pol);
1231 			else if (err == -ESRCH)
1232 				pol = NULL;
1233 			else
1234 				pol = ERR_PTR(err);
1235 		} else
1236 			pol = NULL;
1237 	}
1238 out:
1239 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
1240 	return pol;
1241 }
1242 
1243 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1244 {
1245 	struct net *net = xp_net(pol);
1246 
1247 	list_add(&pol->walk.all, &net->xfrm.policy_all);
1248 	net->xfrm.policy_count[dir]++;
1249 	xfrm_pol_hold(pol);
1250 }
1251 
1252 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1253 						int dir)
1254 {
1255 	struct net *net = xp_net(pol);
1256 
1257 	if (list_empty(&pol->walk.all))
1258 		return NULL;
1259 
1260 	/* Socket policies are not hashed. */
1261 	if (!hlist_unhashed(&pol->bydst)) {
1262 		hlist_del(&pol->bydst);
1263 		hlist_del(&pol->byidx);
1264 	}
1265 
1266 	list_del_init(&pol->walk.all);
1267 	net->xfrm.policy_count[dir]--;
1268 
1269 	return pol;
1270 }
1271 
1272 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1273 {
1274 	__xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1275 }
1276 
1277 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1278 {
1279 	__xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1280 }
1281 
1282 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1283 {
1284 	struct net *net = xp_net(pol);
1285 
1286 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1287 	pol = __xfrm_policy_unlink(pol, dir);
1288 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1289 	if (pol) {
1290 		xfrm_policy_kill(pol);
1291 		return 0;
1292 	}
1293 	return -ENOENT;
1294 }
1295 EXPORT_SYMBOL(xfrm_policy_delete);
1296 
1297 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1298 {
1299 	struct net *net = xp_net(pol);
1300 	struct xfrm_policy *old_pol;
1301 
1302 #ifdef CONFIG_XFRM_SUB_POLICY
1303 	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1304 		return -EINVAL;
1305 #endif
1306 
1307 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
1308 	old_pol = sk->sk_policy[dir];
1309 	sk->sk_policy[dir] = pol;
1310 	if (pol) {
1311 		pol->curlft.add_time = get_seconds();
1312 		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1313 		xfrm_sk_policy_link(pol, dir);
1314 	}
1315 	if (old_pol) {
1316 		if (pol)
1317 			xfrm_policy_requeue(old_pol, pol);
1318 
1319 		/* Unlinking succeeds always. This is the only function
1320 		 * allowed to delete or replace socket policy.
1321 		 */
1322 		xfrm_sk_policy_unlink(old_pol, dir);
1323 	}
1324 	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1325 
1326 	if (old_pol) {
1327 		xfrm_policy_kill(old_pol);
1328 	}
1329 	return 0;
1330 }
1331 
1332 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1333 {
1334 	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1335 	struct net *net = xp_net(old);
1336 
1337 	if (newp) {
1338 		newp->selector = old->selector;
1339 		if (security_xfrm_policy_clone(old->security,
1340 					       &newp->security)) {
1341 			kfree(newp);
1342 			return NULL;  /* ENOMEM */
1343 		}
1344 		newp->lft = old->lft;
1345 		newp->curlft = old->curlft;
1346 		newp->mark = old->mark;
1347 		newp->action = old->action;
1348 		newp->flags = old->flags;
1349 		newp->xfrm_nr = old->xfrm_nr;
1350 		newp->index = old->index;
1351 		newp->type = old->type;
1352 		memcpy(newp->xfrm_vec, old->xfrm_vec,
1353 		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1354 		write_lock_bh(&net->xfrm.xfrm_policy_lock);
1355 		xfrm_sk_policy_link(newp, dir);
1356 		write_unlock_bh(&net->xfrm.xfrm_policy_lock);
1357 		xfrm_pol_put(newp);
1358 	}
1359 	return newp;
1360 }
1361 
1362 int __xfrm_sk_clone_policy(struct sock *sk)
1363 {
1364 	struct xfrm_policy *p0 = sk->sk_policy[0],
1365 			   *p1 = sk->sk_policy[1];
1366 
1367 	sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1368 	if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1369 		return -ENOMEM;
1370 	if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1371 		return -ENOMEM;
1372 	return 0;
1373 }
1374 
1375 static int
1376 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1377 	       unsigned short family)
1378 {
1379 	int err;
1380 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1381 
1382 	if (unlikely(afinfo == NULL))
1383 		return -EINVAL;
1384 	err = afinfo->get_saddr(net, local, remote);
1385 	xfrm_policy_put_afinfo(afinfo);
1386 	return err;
1387 }
1388 
1389 /* Resolve list of templates for the flow, given policy. */
1390 
1391 static int
1392 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1393 		      struct xfrm_state **xfrm, unsigned short family)
1394 {
1395 	struct net *net = xp_net(policy);
1396 	int nx;
1397 	int i, error;
1398 	xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1399 	xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1400 	xfrm_address_t tmp;
1401 
1402 	for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1403 		struct xfrm_state *x;
1404 		xfrm_address_t *remote = daddr;
1405 		xfrm_address_t *local  = saddr;
1406 		struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1407 
1408 		if (tmpl->mode == XFRM_MODE_TUNNEL ||
1409 		    tmpl->mode == XFRM_MODE_BEET) {
1410 			remote = &tmpl->id.daddr;
1411 			local = &tmpl->saddr;
1412 			if (xfrm_addr_any(local, tmpl->encap_family)) {
1413 				error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family);
1414 				if (error)
1415 					goto fail;
1416 				local = &tmp;
1417 			}
1418 		}
1419 
1420 		x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1421 
1422 		if (x && x->km.state == XFRM_STATE_VALID) {
1423 			xfrm[nx++] = x;
1424 			daddr = remote;
1425 			saddr = local;
1426 			continue;
1427 		}
1428 		if (x) {
1429 			error = (x->km.state == XFRM_STATE_ERROR ?
1430 				 -EINVAL : -EAGAIN);
1431 			xfrm_state_put(x);
1432 		} else if (error == -ESRCH) {
1433 			error = -EAGAIN;
1434 		}
1435 
1436 		if (!tmpl->optional)
1437 			goto fail;
1438 	}
1439 	return nx;
1440 
1441 fail:
1442 	for (nx--; nx >= 0; nx--)
1443 		xfrm_state_put(xfrm[nx]);
1444 	return error;
1445 }
1446 
1447 static int
1448 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1449 		  struct xfrm_state **xfrm, unsigned short family)
1450 {
1451 	struct xfrm_state *tp[XFRM_MAX_DEPTH];
1452 	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1453 	int cnx = 0;
1454 	int error;
1455 	int ret;
1456 	int i;
1457 
1458 	for (i = 0; i < npols; i++) {
1459 		if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1460 			error = -ENOBUFS;
1461 			goto fail;
1462 		}
1463 
1464 		ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1465 		if (ret < 0) {
1466 			error = ret;
1467 			goto fail;
1468 		} else
1469 			cnx += ret;
1470 	}
1471 
1472 	/* found states are sorted for outbound processing */
1473 	if (npols > 1)
1474 		xfrm_state_sort(xfrm, tpp, cnx, family);
1475 
1476 	return cnx;
1477 
1478  fail:
1479 	for (cnx--; cnx >= 0; cnx--)
1480 		xfrm_state_put(tpp[cnx]);
1481 	return error;
1482 
1483 }
1484 
1485 /* Check that the bundle accepts the flow and its components are
1486  * still valid.
1487  */
1488 
1489 static inline int xfrm_get_tos(const struct flowi *fl, int family)
1490 {
1491 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1492 	int tos;
1493 
1494 	if (!afinfo)
1495 		return -EINVAL;
1496 
1497 	tos = afinfo->get_tos(fl);
1498 
1499 	xfrm_policy_put_afinfo(afinfo);
1500 
1501 	return tos;
1502 }
1503 
1504 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1505 {
1506 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1507 	struct dst_entry *dst = &xdst->u.dst;
1508 
1509 	if (xdst->route == NULL) {
1510 		/* Dummy bundle - if it has xfrms we were not
1511 		 * able to build bundle as template resolution failed.
1512 		 * It means we need to try again resolving. */
1513 		if (xdst->num_xfrms > 0)
1514 			return NULL;
1515 	} else if (dst->flags & DST_XFRM_QUEUE) {
1516 		return NULL;
1517 	} else {
1518 		/* Real bundle */
1519 		if (stale_bundle(dst))
1520 			return NULL;
1521 	}
1522 
1523 	dst_hold(dst);
1524 	return flo;
1525 }
1526 
1527 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1528 {
1529 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1530 	struct dst_entry *dst = &xdst->u.dst;
1531 
1532 	if (!xdst->route)
1533 		return 0;
1534 	if (stale_bundle(dst))
1535 		return 0;
1536 
1537 	return 1;
1538 }
1539 
1540 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1541 {
1542 	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1543 	struct dst_entry *dst = &xdst->u.dst;
1544 
1545 	dst_free(dst);
1546 }
1547 
1548 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1549 	.get = xfrm_bundle_flo_get,
1550 	.check = xfrm_bundle_flo_check,
1551 	.delete = xfrm_bundle_flo_delete,
1552 };
1553 
1554 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1555 {
1556 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1557 	struct dst_ops *dst_ops;
1558 	struct xfrm_dst *xdst;
1559 
1560 	if (!afinfo)
1561 		return ERR_PTR(-EINVAL);
1562 
1563 	switch (family) {
1564 	case AF_INET:
1565 		dst_ops = &net->xfrm.xfrm4_dst_ops;
1566 		break;
1567 #if IS_ENABLED(CONFIG_IPV6)
1568 	case AF_INET6:
1569 		dst_ops = &net->xfrm.xfrm6_dst_ops;
1570 		break;
1571 #endif
1572 	default:
1573 		BUG();
1574 	}
1575 	xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1576 
1577 	if (likely(xdst)) {
1578 		struct dst_entry *dst = &xdst->u.dst;
1579 
1580 		memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1581 		xdst->flo.ops = &xfrm_bundle_fc_ops;
1582 		if (afinfo->init_dst)
1583 			afinfo->init_dst(net, xdst);
1584 	} else
1585 		xdst = ERR_PTR(-ENOBUFS);
1586 
1587 	xfrm_policy_put_afinfo(afinfo);
1588 
1589 	return xdst;
1590 }
1591 
1592 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1593 				 int nfheader_len)
1594 {
1595 	struct xfrm_policy_afinfo *afinfo =
1596 		xfrm_policy_get_afinfo(dst->ops->family);
1597 	int err;
1598 
1599 	if (!afinfo)
1600 		return -EINVAL;
1601 
1602 	err = afinfo->init_path(path, dst, nfheader_len);
1603 
1604 	xfrm_policy_put_afinfo(afinfo);
1605 
1606 	return err;
1607 }
1608 
1609 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1610 				const struct flowi *fl)
1611 {
1612 	struct xfrm_policy_afinfo *afinfo =
1613 		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1614 	int err;
1615 
1616 	if (!afinfo)
1617 		return -EINVAL;
1618 
1619 	err = afinfo->fill_dst(xdst, dev, fl);
1620 
1621 	xfrm_policy_put_afinfo(afinfo);
1622 
1623 	return err;
1624 }
1625 
1626 
1627 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1628  * all the metrics... Shortly, bundle a bundle.
1629  */
1630 
1631 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1632 					    struct xfrm_state **xfrm, int nx,
1633 					    const struct flowi *fl,
1634 					    struct dst_entry *dst)
1635 {
1636 	struct net *net = xp_net(policy);
1637 	unsigned long now = jiffies;
1638 	struct net_device *dev;
1639 	struct xfrm_mode *inner_mode;
1640 	struct dst_entry *dst_prev = NULL;
1641 	struct dst_entry *dst0 = NULL;
1642 	int i = 0;
1643 	int err;
1644 	int header_len = 0;
1645 	int nfheader_len = 0;
1646 	int trailer_len = 0;
1647 	int tos;
1648 	int family = policy->selector.family;
1649 	xfrm_address_t saddr, daddr;
1650 
1651 	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1652 
1653 	tos = xfrm_get_tos(fl, family);
1654 	err = tos;
1655 	if (tos < 0)
1656 		goto put_states;
1657 
1658 	dst_hold(dst);
1659 
1660 	for (; i < nx; i++) {
1661 		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1662 		struct dst_entry *dst1 = &xdst->u.dst;
1663 
1664 		err = PTR_ERR(xdst);
1665 		if (IS_ERR(xdst)) {
1666 			dst_release(dst);
1667 			goto put_states;
1668 		}
1669 
1670 		if (xfrm[i]->sel.family == AF_UNSPEC) {
1671 			inner_mode = xfrm_ip2inner_mode(xfrm[i],
1672 							xfrm_af2proto(family));
1673 			if (!inner_mode) {
1674 				err = -EAFNOSUPPORT;
1675 				dst_release(dst);
1676 				goto put_states;
1677 			}
1678 		} else
1679 			inner_mode = xfrm[i]->inner_mode;
1680 
1681 		if (!dst_prev)
1682 			dst0 = dst1;
1683 		else {
1684 			dst_prev->child = dst_clone(dst1);
1685 			dst1->flags |= DST_NOHASH;
1686 		}
1687 
1688 		xdst->route = dst;
1689 		dst_copy_metrics(dst1, dst);
1690 
1691 		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1692 			family = xfrm[i]->props.family;
1693 			dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1694 					      family);
1695 			err = PTR_ERR(dst);
1696 			if (IS_ERR(dst))
1697 				goto put_states;
1698 		} else
1699 			dst_hold(dst);
1700 
1701 		dst1->xfrm = xfrm[i];
1702 		xdst->xfrm_genid = xfrm[i]->genid;
1703 
1704 		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1705 		dst1->flags |= DST_HOST;
1706 		dst1->lastuse = now;
1707 
1708 		dst1->input = dst_discard;
1709 		dst1->output = inner_mode->afinfo->output;
1710 
1711 		dst1->next = dst_prev;
1712 		dst_prev = dst1;
1713 
1714 		header_len += xfrm[i]->props.header_len;
1715 		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1716 			nfheader_len += xfrm[i]->props.header_len;
1717 		trailer_len += xfrm[i]->props.trailer_len;
1718 	}
1719 
1720 	dst_prev->child = dst;
1721 	dst0->path = dst;
1722 
1723 	err = -ENODEV;
1724 	dev = dst->dev;
1725 	if (!dev)
1726 		goto free_dst;
1727 
1728 	xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1729 	xfrm_init_pmtu(dst_prev);
1730 
1731 	for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1732 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1733 
1734 		err = xfrm_fill_dst(xdst, dev, fl);
1735 		if (err)
1736 			goto free_dst;
1737 
1738 		dst_prev->header_len = header_len;
1739 		dst_prev->trailer_len = trailer_len;
1740 		header_len -= xdst->u.dst.xfrm->props.header_len;
1741 		trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1742 	}
1743 
1744 out:
1745 	return dst0;
1746 
1747 put_states:
1748 	for (; i < nx; i++)
1749 		xfrm_state_put(xfrm[i]);
1750 free_dst:
1751 	if (dst0)
1752 		dst_free(dst0);
1753 	dst0 = ERR_PTR(err);
1754 	goto out;
1755 }
1756 
1757 #ifdef CONFIG_XFRM_SUB_POLICY
1758 static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
1759 {
1760 	if (!*target) {
1761 		*target = kmalloc(size, GFP_ATOMIC);
1762 		if (!*target)
1763 			return -ENOMEM;
1764 	}
1765 
1766 	memcpy(*target, src, size);
1767 	return 0;
1768 }
1769 #endif
1770 
1771 static int xfrm_dst_update_parent(struct dst_entry *dst,
1772 				  const struct xfrm_selector *sel)
1773 {
1774 #ifdef CONFIG_XFRM_SUB_POLICY
1775 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1776 	return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1777 				   sel, sizeof(*sel));
1778 #else
1779 	return 0;
1780 #endif
1781 }
1782 
1783 static int xfrm_dst_update_origin(struct dst_entry *dst,
1784 				  const struct flowi *fl)
1785 {
1786 #ifdef CONFIG_XFRM_SUB_POLICY
1787 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1788 	return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1789 #else
1790 	return 0;
1791 #endif
1792 }
1793 
1794 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1795 				struct xfrm_policy **pols,
1796 				int *num_pols, int *num_xfrms)
1797 {
1798 	int i;
1799 
1800 	if (*num_pols == 0 || !pols[0]) {
1801 		*num_pols = 0;
1802 		*num_xfrms = 0;
1803 		return 0;
1804 	}
1805 	if (IS_ERR(pols[0]))
1806 		return PTR_ERR(pols[0]);
1807 
1808 	*num_xfrms = pols[0]->xfrm_nr;
1809 
1810 #ifdef CONFIG_XFRM_SUB_POLICY
1811 	if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1812 	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1813 		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1814 						    XFRM_POLICY_TYPE_MAIN,
1815 						    fl, family,
1816 						    XFRM_POLICY_OUT);
1817 		if (pols[1]) {
1818 			if (IS_ERR(pols[1])) {
1819 				xfrm_pols_put(pols, *num_pols);
1820 				return PTR_ERR(pols[1]);
1821 			}
1822 			(*num_pols)++;
1823 			(*num_xfrms) += pols[1]->xfrm_nr;
1824 		}
1825 	}
1826 #endif
1827 	for (i = 0; i < *num_pols; i++) {
1828 		if (pols[i]->action != XFRM_POLICY_ALLOW) {
1829 			*num_xfrms = -1;
1830 			break;
1831 		}
1832 	}
1833 
1834 	return 0;
1835 
1836 }
1837 
1838 static struct xfrm_dst *
1839 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1840 			       const struct flowi *fl, u16 family,
1841 			       struct dst_entry *dst_orig)
1842 {
1843 	struct net *net = xp_net(pols[0]);
1844 	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1845 	struct dst_entry *dst;
1846 	struct xfrm_dst *xdst;
1847 	int err;
1848 
1849 	/* Try to instantiate a bundle */
1850 	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1851 	if (err <= 0) {
1852 		if (err != 0 && err != -EAGAIN)
1853 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1854 		return ERR_PTR(err);
1855 	}
1856 
1857 	dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1858 	if (IS_ERR(dst)) {
1859 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1860 		return ERR_CAST(dst);
1861 	}
1862 
1863 	xdst = (struct xfrm_dst *)dst;
1864 	xdst->num_xfrms = err;
1865 	if (num_pols > 1)
1866 		err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1867 	else
1868 		err = xfrm_dst_update_origin(dst, fl);
1869 	if (unlikely(err)) {
1870 		dst_free(dst);
1871 		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1872 		return ERR_PTR(err);
1873 	}
1874 
1875 	xdst->num_pols = num_pols;
1876 	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1877 	xdst->policy_genid = atomic_read(&pols[0]->genid);
1878 
1879 	return xdst;
1880 }
1881 
1882 static void xfrm_policy_queue_process(unsigned long arg)
1883 {
1884 	struct sk_buff *skb;
1885 	struct sock *sk;
1886 	struct dst_entry *dst;
1887 	struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1888 	struct xfrm_policy_queue *pq = &pol->polq;
1889 	struct flowi fl;
1890 	struct sk_buff_head list;
1891 
1892 	spin_lock(&pq->hold_queue.lock);
1893 	skb = skb_peek(&pq->hold_queue);
1894 	if (!skb) {
1895 		spin_unlock(&pq->hold_queue.lock);
1896 		goto out;
1897 	}
1898 	dst = skb_dst(skb);
1899 	sk = skb->sk;
1900 	xfrm_decode_session(skb, &fl, dst->ops->family);
1901 	spin_unlock(&pq->hold_queue.lock);
1902 
1903 	dst_hold(dst->path);
1904 	dst = xfrm_lookup(xp_net(pol), dst->path, &fl,
1905 			  sk, 0);
1906 	if (IS_ERR(dst))
1907 		goto purge_queue;
1908 
1909 	if (dst->flags & DST_XFRM_QUEUE) {
1910 		dst_release(dst);
1911 
1912 		if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1913 			goto purge_queue;
1914 
1915 		pq->timeout = pq->timeout << 1;
1916 		if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1917 			xfrm_pol_hold(pol);
1918 	goto out;
1919 	}
1920 
1921 	dst_release(dst);
1922 
1923 	__skb_queue_head_init(&list);
1924 
1925 	spin_lock(&pq->hold_queue.lock);
1926 	pq->timeout = 0;
1927 	skb_queue_splice_init(&pq->hold_queue, &list);
1928 	spin_unlock(&pq->hold_queue.lock);
1929 
1930 	while (!skb_queue_empty(&list)) {
1931 		skb = __skb_dequeue(&list);
1932 
1933 		xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1934 		dst_hold(skb_dst(skb)->path);
1935 		dst = xfrm_lookup(xp_net(pol), skb_dst(skb)->path,
1936 				  &fl, skb->sk, 0);
1937 		if (IS_ERR(dst)) {
1938 			kfree_skb(skb);
1939 			continue;
1940 		}
1941 
1942 		nf_reset(skb);
1943 		skb_dst_drop(skb);
1944 		skb_dst_set(skb, dst);
1945 
1946 		dst_output(skb);
1947 	}
1948 
1949 out:
1950 	xfrm_pol_put(pol);
1951 	return;
1952 
1953 purge_queue:
1954 	pq->timeout = 0;
1955 	skb_queue_purge(&pq->hold_queue);
1956 	xfrm_pol_put(pol);
1957 }
1958 
1959 static int xdst_queue_output(struct sock *sk, struct sk_buff *skb)
1960 {
1961 	unsigned long sched_next;
1962 	struct dst_entry *dst = skb_dst(skb);
1963 	struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1964 	struct xfrm_policy *pol = xdst->pols[0];
1965 	struct xfrm_policy_queue *pq = &pol->polq;
1966 
1967 	if (unlikely(skb_fclone_busy(sk, skb))) {
1968 		kfree_skb(skb);
1969 		return 0;
1970 	}
1971 
1972 	if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1973 		kfree_skb(skb);
1974 		return -EAGAIN;
1975 	}
1976 
1977 	skb_dst_force(skb);
1978 
1979 	spin_lock_bh(&pq->hold_queue.lock);
1980 
1981 	if (!pq->timeout)
1982 		pq->timeout = XFRM_QUEUE_TMO_MIN;
1983 
1984 	sched_next = jiffies + pq->timeout;
1985 
1986 	if (del_timer(&pq->hold_timer)) {
1987 		if (time_before(pq->hold_timer.expires, sched_next))
1988 			sched_next = pq->hold_timer.expires;
1989 		xfrm_pol_put(pol);
1990 	}
1991 
1992 	__skb_queue_tail(&pq->hold_queue, skb);
1993 	if (!mod_timer(&pq->hold_timer, sched_next))
1994 		xfrm_pol_hold(pol);
1995 
1996 	spin_unlock_bh(&pq->hold_queue.lock);
1997 
1998 	return 0;
1999 }
2000 
2001 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2002 						 struct xfrm_flo *xflo,
2003 						 const struct flowi *fl,
2004 						 int num_xfrms,
2005 						 u16 family)
2006 {
2007 	int err;
2008 	struct net_device *dev;
2009 	struct dst_entry *dst;
2010 	struct dst_entry *dst1;
2011 	struct xfrm_dst *xdst;
2012 
2013 	xdst = xfrm_alloc_dst(net, family);
2014 	if (IS_ERR(xdst))
2015 		return xdst;
2016 
2017 	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2018 	    net->xfrm.sysctl_larval_drop ||
2019 	    num_xfrms <= 0)
2020 		return xdst;
2021 
2022 	dst = xflo->dst_orig;
2023 	dst1 = &xdst->u.dst;
2024 	dst_hold(dst);
2025 	xdst->route = dst;
2026 
2027 	dst_copy_metrics(dst1, dst);
2028 
2029 	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2030 	dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2031 	dst1->lastuse = jiffies;
2032 
2033 	dst1->input = dst_discard;
2034 	dst1->output = xdst_queue_output;
2035 
2036 	dst_hold(dst);
2037 	dst1->child = dst;
2038 	dst1->path = dst;
2039 
2040 	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2041 
2042 	err = -ENODEV;
2043 	dev = dst->dev;
2044 	if (!dev)
2045 		goto free_dst;
2046 
2047 	err = xfrm_fill_dst(xdst, dev, fl);
2048 	if (err)
2049 		goto free_dst;
2050 
2051 out:
2052 	return xdst;
2053 
2054 free_dst:
2055 	dst_release(dst1);
2056 	xdst = ERR_PTR(err);
2057 	goto out;
2058 }
2059 
2060 static struct flow_cache_object *
2061 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
2062 		   struct flow_cache_object *oldflo, void *ctx)
2063 {
2064 	struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
2065 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2066 	struct xfrm_dst *xdst, *new_xdst;
2067 	int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
2068 
2069 	/* Check if the policies from old bundle are usable */
2070 	xdst = NULL;
2071 	if (oldflo) {
2072 		xdst = container_of(oldflo, struct xfrm_dst, flo);
2073 		num_pols = xdst->num_pols;
2074 		num_xfrms = xdst->num_xfrms;
2075 		pol_dead = 0;
2076 		for (i = 0; i < num_pols; i++) {
2077 			pols[i] = xdst->pols[i];
2078 			pol_dead |= pols[i]->walk.dead;
2079 		}
2080 		if (pol_dead) {
2081 			dst_free(&xdst->u.dst);
2082 			xdst = NULL;
2083 			num_pols = 0;
2084 			num_xfrms = 0;
2085 			oldflo = NULL;
2086 		}
2087 	}
2088 
2089 	/* Resolve policies to use if we couldn't get them from
2090 	 * previous cache entry */
2091 	if (xdst == NULL) {
2092 		num_pols = 1;
2093 		pols[0] = __xfrm_policy_lookup(net, fl, family,
2094 					       flow_to_policy_dir(dir));
2095 		err = xfrm_expand_policies(fl, family, pols,
2096 					   &num_pols, &num_xfrms);
2097 		if (err < 0)
2098 			goto inc_error;
2099 		if (num_pols == 0)
2100 			return NULL;
2101 		if (num_xfrms <= 0)
2102 			goto make_dummy_bundle;
2103 	}
2104 
2105 	new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2106 						  xflo->dst_orig);
2107 	if (IS_ERR(new_xdst)) {
2108 		err = PTR_ERR(new_xdst);
2109 		if (err != -EAGAIN)
2110 			goto error;
2111 		if (oldflo == NULL)
2112 			goto make_dummy_bundle;
2113 		dst_hold(&xdst->u.dst);
2114 		return oldflo;
2115 	} else if (new_xdst == NULL) {
2116 		num_xfrms = 0;
2117 		if (oldflo == NULL)
2118 			goto make_dummy_bundle;
2119 		xdst->num_xfrms = 0;
2120 		dst_hold(&xdst->u.dst);
2121 		return oldflo;
2122 	}
2123 
2124 	/* Kill the previous bundle */
2125 	if (xdst) {
2126 		/* The policies were stolen for newly generated bundle */
2127 		xdst->num_pols = 0;
2128 		dst_free(&xdst->u.dst);
2129 	}
2130 
2131 	/* Flow cache does not have reference, it dst_free()'s,
2132 	 * but we do need to return one reference for original caller */
2133 	dst_hold(&new_xdst->u.dst);
2134 	return &new_xdst->flo;
2135 
2136 make_dummy_bundle:
2137 	/* We found policies, but there's no bundles to instantiate:
2138 	 * either because the policy blocks, has no transformations or
2139 	 * we could not build template (no xfrm_states).*/
2140 	xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2141 	if (IS_ERR(xdst)) {
2142 		xfrm_pols_put(pols, num_pols);
2143 		return ERR_CAST(xdst);
2144 	}
2145 	xdst->num_pols = num_pols;
2146 	xdst->num_xfrms = num_xfrms;
2147 	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2148 
2149 	dst_hold(&xdst->u.dst);
2150 	return &xdst->flo;
2151 
2152 inc_error:
2153 	XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2154 error:
2155 	if (xdst != NULL)
2156 		dst_free(&xdst->u.dst);
2157 	else
2158 		xfrm_pols_put(pols, num_pols);
2159 	return ERR_PTR(err);
2160 }
2161 
2162 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2163 					struct dst_entry *dst_orig)
2164 {
2165 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2166 	struct dst_entry *ret;
2167 
2168 	if (!afinfo) {
2169 		dst_release(dst_orig);
2170 		return ERR_PTR(-EINVAL);
2171 	} else {
2172 		ret = afinfo->blackhole_route(net, dst_orig);
2173 	}
2174 	xfrm_policy_put_afinfo(afinfo);
2175 
2176 	return ret;
2177 }
2178 
2179 /* Main function: finds/creates a bundle for given flow.
2180  *
2181  * At the moment we eat a raw IP route. Mostly to speed up lookups
2182  * on interfaces with disabled IPsec.
2183  */
2184 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2185 			      const struct flowi *fl,
2186 			      struct sock *sk, int flags)
2187 {
2188 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2189 	struct flow_cache_object *flo;
2190 	struct xfrm_dst *xdst;
2191 	struct dst_entry *dst, *route;
2192 	u16 family = dst_orig->ops->family;
2193 	u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2194 	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2195 
2196 	dst = NULL;
2197 	xdst = NULL;
2198 	route = NULL;
2199 
2200 	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2201 		num_pols = 1;
2202 		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2203 		err = xfrm_expand_policies(fl, family, pols,
2204 					   &num_pols, &num_xfrms);
2205 		if (err < 0)
2206 			goto dropdst;
2207 
2208 		if (num_pols) {
2209 			if (num_xfrms <= 0) {
2210 				drop_pols = num_pols;
2211 				goto no_transform;
2212 			}
2213 
2214 			xdst = xfrm_resolve_and_create_bundle(
2215 					pols, num_pols, fl,
2216 					family, dst_orig);
2217 			if (IS_ERR(xdst)) {
2218 				xfrm_pols_put(pols, num_pols);
2219 				err = PTR_ERR(xdst);
2220 				goto dropdst;
2221 			} else if (xdst == NULL) {
2222 				num_xfrms = 0;
2223 				drop_pols = num_pols;
2224 				goto no_transform;
2225 			}
2226 
2227 			dst_hold(&xdst->u.dst);
2228 			xdst->u.dst.flags |= DST_NOCACHE;
2229 			route = xdst->route;
2230 		}
2231 	}
2232 
2233 	if (xdst == NULL) {
2234 		struct xfrm_flo xflo;
2235 
2236 		xflo.dst_orig = dst_orig;
2237 		xflo.flags = flags;
2238 
2239 		/* To accelerate a bit...  */
2240 		if ((dst_orig->flags & DST_NOXFRM) ||
2241 		    !net->xfrm.policy_count[XFRM_POLICY_OUT])
2242 			goto nopol;
2243 
2244 		flo = flow_cache_lookup(net, fl, family, dir,
2245 					xfrm_bundle_lookup, &xflo);
2246 		if (flo == NULL)
2247 			goto nopol;
2248 		if (IS_ERR(flo)) {
2249 			err = PTR_ERR(flo);
2250 			goto dropdst;
2251 		}
2252 		xdst = container_of(flo, struct xfrm_dst, flo);
2253 
2254 		num_pols = xdst->num_pols;
2255 		num_xfrms = xdst->num_xfrms;
2256 		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2257 		route = xdst->route;
2258 	}
2259 
2260 	dst = &xdst->u.dst;
2261 	if (route == NULL && num_xfrms > 0) {
2262 		/* The only case when xfrm_bundle_lookup() returns a
2263 		 * bundle with null route, is when the template could
2264 		 * not be resolved. It means policies are there, but
2265 		 * bundle could not be created, since we don't yet
2266 		 * have the xfrm_state's. We need to wait for KM to
2267 		 * negotiate new SA's or bail out with error.*/
2268 		if (net->xfrm.sysctl_larval_drop) {
2269 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2270 			err = -EREMOTE;
2271 			goto error;
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 	if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2323 		dst_release(dst_orig);
2324 	xfrm_pols_put(pols, drop_pols);
2325 	return ERR_PTR(err);
2326 }
2327 EXPORT_SYMBOL(xfrm_lookup);
2328 
2329 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2330  * Otherwise we may send out blackholed packets.
2331  */
2332 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2333 				    const struct flowi *fl,
2334 				    struct sock *sk, int flags)
2335 {
2336 	struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2337 					    flags | XFRM_LOOKUP_QUEUE |
2338 					    XFRM_LOOKUP_KEEP_DST_REF);
2339 
2340 	if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2341 		return make_blackhole(net, dst_orig->ops->family, dst_orig);
2342 
2343 	return dst;
2344 }
2345 EXPORT_SYMBOL(xfrm_lookup_route);
2346 
2347 static inline int
2348 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2349 {
2350 	struct xfrm_state *x;
2351 
2352 	if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2353 		return 0;
2354 	x = skb->sp->xvec[idx];
2355 	if (!x->type->reject)
2356 		return 0;
2357 	return x->type->reject(x, skb, fl);
2358 }
2359 
2360 /* When skb is transformed back to its "native" form, we have to
2361  * check policy restrictions. At the moment we make this in maximally
2362  * stupid way. Shame on me. :-) Of course, connected sockets must
2363  * have policy cached at them.
2364  */
2365 
2366 static inline int
2367 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2368 	      unsigned short family)
2369 {
2370 	if (xfrm_state_kern(x))
2371 		return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2372 	return	x->id.proto == tmpl->id.proto &&
2373 		(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2374 		(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2375 		x->props.mode == tmpl->mode &&
2376 		(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2377 		 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2378 		!(x->props.mode != XFRM_MODE_TRANSPORT &&
2379 		  xfrm_state_addr_cmp(tmpl, x, family));
2380 }
2381 
2382 /*
2383  * 0 or more than 0 is returned when validation is succeeded (either bypass
2384  * because of optional transport mode, or next index of the mathced secpath
2385  * state with the template.
2386  * -1 is returned when no matching template is found.
2387  * Otherwise "-2 - errored_index" is returned.
2388  */
2389 static inline int
2390 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2391 	       unsigned short family)
2392 {
2393 	int idx = start;
2394 
2395 	if (tmpl->optional) {
2396 		if (tmpl->mode == XFRM_MODE_TRANSPORT)
2397 			return start;
2398 	} else
2399 		start = -1;
2400 	for (; idx < sp->len; idx++) {
2401 		if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2402 			return ++idx;
2403 		if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2404 			if (start == -1)
2405 				start = -2-idx;
2406 			break;
2407 		}
2408 	}
2409 	return start;
2410 }
2411 
2412 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2413 			  unsigned int family, int reverse)
2414 {
2415 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2416 	int err;
2417 
2418 	if (unlikely(afinfo == NULL))
2419 		return -EAFNOSUPPORT;
2420 
2421 	afinfo->decode_session(skb, fl, reverse);
2422 	err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2423 	xfrm_policy_put_afinfo(afinfo);
2424 	return err;
2425 }
2426 EXPORT_SYMBOL(__xfrm_decode_session);
2427 
2428 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2429 {
2430 	for (; k < sp->len; k++) {
2431 		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2432 			*idxp = k;
2433 			return 1;
2434 		}
2435 	}
2436 
2437 	return 0;
2438 }
2439 
2440 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2441 			unsigned short family)
2442 {
2443 	struct net *net = dev_net(skb->dev);
2444 	struct xfrm_policy *pol;
2445 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2446 	int npols = 0;
2447 	int xfrm_nr;
2448 	int pi;
2449 	int reverse;
2450 	struct flowi fl;
2451 	u8 fl_dir;
2452 	int xerr_idx = -1;
2453 
2454 	reverse = dir & ~XFRM_POLICY_MASK;
2455 	dir &= XFRM_POLICY_MASK;
2456 	fl_dir = policy_to_flow_dir(dir);
2457 
2458 	if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2459 		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2460 		return 0;
2461 	}
2462 
2463 	nf_nat_decode_session(skb, &fl, family);
2464 
2465 	/* First, check used SA against their selectors. */
2466 	if (skb->sp) {
2467 		int i;
2468 
2469 		for (i = skb->sp->len-1; i >= 0; i--) {
2470 			struct xfrm_state *x = skb->sp->xvec[i];
2471 			if (!xfrm_selector_match(&x->sel, &fl, family)) {
2472 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2473 				return 0;
2474 			}
2475 		}
2476 	}
2477 
2478 	pol = NULL;
2479 	if (sk && sk->sk_policy[dir]) {
2480 		pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2481 		if (IS_ERR(pol)) {
2482 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2483 			return 0;
2484 		}
2485 	}
2486 
2487 	if (!pol) {
2488 		struct flow_cache_object *flo;
2489 
2490 		flo = flow_cache_lookup(net, &fl, family, fl_dir,
2491 					xfrm_policy_lookup, NULL);
2492 		if (IS_ERR_OR_NULL(flo))
2493 			pol = ERR_CAST(flo);
2494 		else
2495 			pol = container_of(flo, struct xfrm_policy, flo);
2496 	}
2497 
2498 	if (IS_ERR(pol)) {
2499 		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2500 		return 0;
2501 	}
2502 
2503 	if (!pol) {
2504 		if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2505 			xfrm_secpath_reject(xerr_idx, skb, &fl);
2506 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2507 			return 0;
2508 		}
2509 		return 1;
2510 	}
2511 
2512 	pol->curlft.use_time = get_seconds();
2513 
2514 	pols[0] = pol;
2515 	npols++;
2516 #ifdef CONFIG_XFRM_SUB_POLICY
2517 	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2518 		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2519 						    &fl, family,
2520 						    XFRM_POLICY_IN);
2521 		if (pols[1]) {
2522 			if (IS_ERR(pols[1])) {
2523 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2524 				return 0;
2525 			}
2526 			pols[1]->curlft.use_time = get_seconds();
2527 			npols++;
2528 		}
2529 	}
2530 #endif
2531 
2532 	if (pol->action == XFRM_POLICY_ALLOW) {
2533 		struct sec_path *sp;
2534 		static struct sec_path dummy;
2535 		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2536 		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2537 		struct xfrm_tmpl **tpp = tp;
2538 		int ti = 0;
2539 		int i, k;
2540 
2541 		if ((sp = skb->sp) == NULL)
2542 			sp = &dummy;
2543 
2544 		for (pi = 0; pi < npols; pi++) {
2545 			if (pols[pi] != pol &&
2546 			    pols[pi]->action != XFRM_POLICY_ALLOW) {
2547 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2548 				goto reject;
2549 			}
2550 			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2551 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2552 				goto reject_error;
2553 			}
2554 			for (i = 0; i < pols[pi]->xfrm_nr; i++)
2555 				tpp[ti++] = &pols[pi]->xfrm_vec[i];
2556 		}
2557 		xfrm_nr = ti;
2558 		if (npols > 1) {
2559 			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2560 			tpp = stp;
2561 		}
2562 
2563 		/* For each tunnel xfrm, find the first matching tmpl.
2564 		 * For each tmpl before that, find corresponding xfrm.
2565 		 * Order is _important_. Later we will implement
2566 		 * some barriers, but at the moment barriers
2567 		 * are implied between each two transformations.
2568 		 */
2569 		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2570 			k = xfrm_policy_ok(tpp[i], sp, k, family);
2571 			if (k < 0) {
2572 				if (k < -1)
2573 					/* "-2 - errored_index" returned */
2574 					xerr_idx = -(2+k);
2575 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2576 				goto reject;
2577 			}
2578 		}
2579 
2580 		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2581 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2582 			goto reject;
2583 		}
2584 
2585 		xfrm_pols_put(pols, npols);
2586 		return 1;
2587 	}
2588 	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2589 
2590 reject:
2591 	xfrm_secpath_reject(xerr_idx, skb, &fl);
2592 reject_error:
2593 	xfrm_pols_put(pols, npols);
2594 	return 0;
2595 }
2596 EXPORT_SYMBOL(__xfrm_policy_check);
2597 
2598 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2599 {
2600 	struct net *net = dev_net(skb->dev);
2601 	struct flowi fl;
2602 	struct dst_entry *dst;
2603 	int res = 1;
2604 
2605 	if (xfrm_decode_session(skb, &fl, family) < 0) {
2606 		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2607 		return 0;
2608 	}
2609 
2610 	skb_dst_force(skb);
2611 
2612 	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2613 	if (IS_ERR(dst)) {
2614 		res = 0;
2615 		dst = NULL;
2616 	}
2617 	skb_dst_set(skb, dst);
2618 	return res;
2619 }
2620 EXPORT_SYMBOL(__xfrm_route_forward);
2621 
2622 /* Optimize later using cookies and generation ids. */
2623 
2624 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2625 {
2626 	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2627 	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2628 	 * get validated by dst_ops->check on every use.  We do this
2629 	 * because when a normal route referenced by an XFRM dst is
2630 	 * obsoleted we do not go looking around for all parent
2631 	 * referencing XFRM dsts so that we can invalidate them.  It
2632 	 * is just too much work.  Instead we make the checks here on
2633 	 * every use.  For example:
2634 	 *
2635 	 *	XFRM dst A --> IPv4 dst X
2636 	 *
2637 	 * X is the "xdst->route" of A (X is also the "dst->path" of A
2638 	 * in this example).  If X is marked obsolete, "A" will not
2639 	 * notice.  That's what we are validating here via the
2640 	 * stale_bundle() check.
2641 	 *
2642 	 * When a policy's bundle is pruned, we dst_free() the XFRM
2643 	 * dst which causes it's ->obsolete field to be set to
2644 	 * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2645 	 * this, we want to force a new route lookup.
2646 	 */
2647 	if (dst->obsolete < 0 && !stale_bundle(dst))
2648 		return dst;
2649 
2650 	return NULL;
2651 }
2652 
2653 static int stale_bundle(struct dst_entry *dst)
2654 {
2655 	return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2656 }
2657 
2658 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2659 {
2660 	while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2661 		dst->dev = dev_net(dev)->loopback_dev;
2662 		dev_hold(dst->dev);
2663 		dev_put(dev);
2664 	}
2665 }
2666 EXPORT_SYMBOL(xfrm_dst_ifdown);
2667 
2668 static void xfrm_link_failure(struct sk_buff *skb)
2669 {
2670 	/* Impossible. Such dst must be popped before reaches point of failure. */
2671 }
2672 
2673 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2674 {
2675 	if (dst) {
2676 		if (dst->obsolete) {
2677 			dst_release(dst);
2678 			dst = NULL;
2679 		}
2680 	}
2681 	return dst;
2682 }
2683 
2684 void xfrm_garbage_collect(struct net *net)
2685 {
2686 	flow_cache_flush(net);
2687 }
2688 EXPORT_SYMBOL(xfrm_garbage_collect);
2689 
2690 static void xfrm_garbage_collect_deferred(struct net *net)
2691 {
2692 	flow_cache_flush_deferred(net);
2693 }
2694 
2695 static void xfrm_init_pmtu(struct dst_entry *dst)
2696 {
2697 	do {
2698 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2699 		u32 pmtu, route_mtu_cached;
2700 
2701 		pmtu = dst_mtu(dst->child);
2702 		xdst->child_mtu_cached = pmtu;
2703 
2704 		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2705 
2706 		route_mtu_cached = dst_mtu(xdst->route);
2707 		xdst->route_mtu_cached = route_mtu_cached;
2708 
2709 		if (pmtu > route_mtu_cached)
2710 			pmtu = route_mtu_cached;
2711 
2712 		dst_metric_set(dst, RTAX_MTU, pmtu);
2713 	} while ((dst = dst->next));
2714 }
2715 
2716 /* Check that the bundle accepts the flow and its components are
2717  * still valid.
2718  */
2719 
2720 static int xfrm_bundle_ok(struct xfrm_dst *first)
2721 {
2722 	struct dst_entry *dst = &first->u.dst;
2723 	struct xfrm_dst *last;
2724 	u32 mtu;
2725 
2726 	if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2727 	    (dst->dev && !netif_running(dst->dev)))
2728 		return 0;
2729 
2730 	if (dst->flags & DST_XFRM_QUEUE)
2731 		return 1;
2732 
2733 	last = NULL;
2734 
2735 	do {
2736 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2737 
2738 		if (dst->xfrm->km.state != XFRM_STATE_VALID)
2739 			return 0;
2740 		if (xdst->xfrm_genid != dst->xfrm->genid)
2741 			return 0;
2742 		if (xdst->num_pols > 0 &&
2743 		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2744 			return 0;
2745 
2746 		mtu = dst_mtu(dst->child);
2747 		if (xdst->child_mtu_cached != mtu) {
2748 			last = xdst;
2749 			xdst->child_mtu_cached = mtu;
2750 		}
2751 
2752 		if (!dst_check(xdst->route, xdst->route_cookie))
2753 			return 0;
2754 		mtu = dst_mtu(xdst->route);
2755 		if (xdst->route_mtu_cached != mtu) {
2756 			last = xdst;
2757 			xdst->route_mtu_cached = mtu;
2758 		}
2759 
2760 		dst = dst->child;
2761 	} while (dst->xfrm);
2762 
2763 	if (likely(!last))
2764 		return 1;
2765 
2766 	mtu = last->child_mtu_cached;
2767 	for (;;) {
2768 		dst = &last->u.dst;
2769 
2770 		mtu = xfrm_state_mtu(dst->xfrm, mtu);
2771 		if (mtu > last->route_mtu_cached)
2772 			mtu = last->route_mtu_cached;
2773 		dst_metric_set(dst, RTAX_MTU, mtu);
2774 
2775 		if (last == first)
2776 			break;
2777 
2778 		last = (struct xfrm_dst *)last->u.dst.next;
2779 		last->child_mtu_cached = mtu;
2780 	}
2781 
2782 	return 1;
2783 }
2784 
2785 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2786 {
2787 	return dst_metric_advmss(dst->path);
2788 }
2789 
2790 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2791 {
2792 	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2793 
2794 	return mtu ? : dst_mtu(dst->path);
2795 }
2796 
2797 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2798 					   struct sk_buff *skb,
2799 					   const void *daddr)
2800 {
2801 	return dst->path->ops->neigh_lookup(dst, skb, daddr);
2802 }
2803 
2804 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2805 {
2806 	struct net *net;
2807 	int err = 0;
2808 	if (unlikely(afinfo == NULL))
2809 		return -EINVAL;
2810 	if (unlikely(afinfo->family >= NPROTO))
2811 		return -EAFNOSUPPORT;
2812 	spin_lock(&xfrm_policy_afinfo_lock);
2813 	if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2814 		err = -EEXIST;
2815 	else {
2816 		struct dst_ops *dst_ops = afinfo->dst_ops;
2817 		if (likely(dst_ops->kmem_cachep == NULL))
2818 			dst_ops->kmem_cachep = xfrm_dst_cache;
2819 		if (likely(dst_ops->check == NULL))
2820 			dst_ops->check = xfrm_dst_check;
2821 		if (likely(dst_ops->default_advmss == NULL))
2822 			dst_ops->default_advmss = xfrm_default_advmss;
2823 		if (likely(dst_ops->mtu == NULL))
2824 			dst_ops->mtu = xfrm_mtu;
2825 		if (likely(dst_ops->negative_advice == NULL))
2826 			dst_ops->negative_advice = xfrm_negative_advice;
2827 		if (likely(dst_ops->link_failure == NULL))
2828 			dst_ops->link_failure = xfrm_link_failure;
2829 		if (likely(dst_ops->neigh_lookup == NULL))
2830 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
2831 		if (likely(afinfo->garbage_collect == NULL))
2832 			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2833 		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
2834 	}
2835 	spin_unlock(&xfrm_policy_afinfo_lock);
2836 
2837 	rtnl_lock();
2838 	for_each_net(net) {
2839 		struct dst_ops *xfrm_dst_ops;
2840 
2841 		switch (afinfo->family) {
2842 		case AF_INET:
2843 			xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2844 			break;
2845 #if IS_ENABLED(CONFIG_IPV6)
2846 		case AF_INET6:
2847 			xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2848 			break;
2849 #endif
2850 		default:
2851 			BUG();
2852 		}
2853 		*xfrm_dst_ops = *afinfo->dst_ops;
2854 	}
2855 	rtnl_unlock();
2856 
2857 	return err;
2858 }
2859 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2860 
2861 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2862 {
2863 	int err = 0;
2864 	if (unlikely(afinfo == NULL))
2865 		return -EINVAL;
2866 	if (unlikely(afinfo->family >= NPROTO))
2867 		return -EAFNOSUPPORT;
2868 	spin_lock(&xfrm_policy_afinfo_lock);
2869 	if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2870 		if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2871 			err = -EINVAL;
2872 		else
2873 			RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
2874 					 NULL);
2875 	}
2876 	spin_unlock(&xfrm_policy_afinfo_lock);
2877 	if (!err) {
2878 		struct dst_ops *dst_ops = afinfo->dst_ops;
2879 
2880 		synchronize_rcu();
2881 
2882 		dst_ops->kmem_cachep = NULL;
2883 		dst_ops->check = NULL;
2884 		dst_ops->negative_advice = NULL;
2885 		dst_ops->link_failure = NULL;
2886 		afinfo->garbage_collect = NULL;
2887 	}
2888 	return err;
2889 }
2890 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2891 
2892 static void __net_init xfrm_dst_ops_init(struct net *net)
2893 {
2894 	struct xfrm_policy_afinfo *afinfo;
2895 
2896 	rcu_read_lock();
2897 	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]);
2898 	if (afinfo)
2899 		net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2900 #if IS_ENABLED(CONFIG_IPV6)
2901 	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]);
2902 	if (afinfo)
2903 		net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2904 #endif
2905 	rcu_read_unlock();
2906 }
2907 
2908 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2909 {
2910 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2911 
2912 	switch (event) {
2913 	case NETDEV_DOWN:
2914 		xfrm_garbage_collect(dev_net(dev));
2915 	}
2916 	return NOTIFY_DONE;
2917 }
2918 
2919 static struct notifier_block xfrm_dev_notifier = {
2920 	.notifier_call	= xfrm_dev_event,
2921 };
2922 
2923 #ifdef CONFIG_XFRM_STATISTICS
2924 static int __net_init xfrm_statistics_init(struct net *net)
2925 {
2926 	int rv;
2927 	net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2928 	if (!net->mib.xfrm_statistics)
2929 		return -ENOMEM;
2930 	rv = xfrm_proc_init(net);
2931 	if (rv < 0)
2932 		free_percpu(net->mib.xfrm_statistics);
2933 	return rv;
2934 }
2935 
2936 static void xfrm_statistics_fini(struct net *net)
2937 {
2938 	xfrm_proc_fini(net);
2939 	free_percpu(net->mib.xfrm_statistics);
2940 }
2941 #else
2942 static int __net_init xfrm_statistics_init(struct net *net)
2943 {
2944 	return 0;
2945 }
2946 
2947 static void xfrm_statistics_fini(struct net *net)
2948 {
2949 }
2950 #endif
2951 
2952 static int __net_init xfrm_policy_init(struct net *net)
2953 {
2954 	unsigned int hmask, sz;
2955 	int dir;
2956 
2957 	if (net_eq(net, &init_net))
2958 		xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2959 					   sizeof(struct xfrm_dst),
2960 					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2961 					   NULL);
2962 
2963 	hmask = 8 - 1;
2964 	sz = (hmask+1) * sizeof(struct hlist_head);
2965 
2966 	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2967 	if (!net->xfrm.policy_byidx)
2968 		goto out_byidx;
2969 	net->xfrm.policy_idx_hmask = hmask;
2970 
2971 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2972 		struct xfrm_policy_hash *htab;
2973 
2974 		net->xfrm.policy_count[dir] = 0;
2975 		net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2976 		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2977 
2978 		htab = &net->xfrm.policy_bydst[dir];
2979 		htab->table = xfrm_hash_alloc(sz);
2980 		if (!htab->table)
2981 			goto out_bydst;
2982 		htab->hmask = hmask;
2983 		htab->dbits4 = 32;
2984 		htab->sbits4 = 32;
2985 		htab->dbits6 = 128;
2986 		htab->sbits6 = 128;
2987 	}
2988 	net->xfrm.policy_hthresh.lbits4 = 32;
2989 	net->xfrm.policy_hthresh.rbits4 = 32;
2990 	net->xfrm.policy_hthresh.lbits6 = 128;
2991 	net->xfrm.policy_hthresh.rbits6 = 128;
2992 
2993 	seqlock_init(&net->xfrm.policy_hthresh.lock);
2994 
2995 	INIT_LIST_HEAD(&net->xfrm.policy_all);
2996 	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2997 	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2998 	if (net_eq(net, &init_net))
2999 		register_netdevice_notifier(&xfrm_dev_notifier);
3000 	return 0;
3001 
3002 out_bydst:
3003 	for (dir--; dir >= 0; dir--) {
3004 		struct xfrm_policy_hash *htab;
3005 
3006 		htab = &net->xfrm.policy_bydst[dir];
3007 		xfrm_hash_free(htab->table, sz);
3008 	}
3009 	xfrm_hash_free(net->xfrm.policy_byidx, sz);
3010 out_byidx:
3011 	return -ENOMEM;
3012 }
3013 
3014 static void xfrm_policy_fini(struct net *net)
3015 {
3016 	unsigned int sz;
3017 	int dir;
3018 
3019 	flush_work(&net->xfrm.policy_hash_work);
3020 #ifdef CONFIG_XFRM_SUB_POLICY
3021 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
3022 #endif
3023 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
3024 
3025 	WARN_ON(!list_empty(&net->xfrm.policy_all));
3026 
3027 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
3028 		struct xfrm_policy_hash *htab;
3029 
3030 		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
3031 
3032 		htab = &net->xfrm.policy_bydst[dir];
3033 		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
3034 		WARN_ON(!hlist_empty(htab->table));
3035 		xfrm_hash_free(htab->table, sz);
3036 	}
3037 
3038 	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
3039 	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
3040 	xfrm_hash_free(net->xfrm.policy_byidx, sz);
3041 }
3042 
3043 static int __net_init xfrm_net_init(struct net *net)
3044 {
3045 	int rv;
3046 
3047 	rv = xfrm_statistics_init(net);
3048 	if (rv < 0)
3049 		goto out_statistics;
3050 	rv = xfrm_state_init(net);
3051 	if (rv < 0)
3052 		goto out_state;
3053 	rv = xfrm_policy_init(net);
3054 	if (rv < 0)
3055 		goto out_policy;
3056 	xfrm_dst_ops_init(net);
3057 	rv = xfrm_sysctl_init(net);
3058 	if (rv < 0)
3059 		goto out_sysctl;
3060 	rv = flow_cache_init(net);
3061 	if (rv < 0)
3062 		goto out;
3063 
3064 	/* Initialize the per-net locks here */
3065 	spin_lock_init(&net->xfrm.xfrm_state_lock);
3066 	rwlock_init(&net->xfrm.xfrm_policy_lock);
3067 	mutex_init(&net->xfrm.xfrm_cfg_mutex);
3068 
3069 	return 0;
3070 
3071 out:
3072 	xfrm_sysctl_fini(net);
3073 out_sysctl:
3074 	xfrm_policy_fini(net);
3075 out_policy:
3076 	xfrm_state_fini(net);
3077 out_state:
3078 	xfrm_statistics_fini(net);
3079 out_statistics:
3080 	return rv;
3081 }
3082 
3083 static void __net_exit xfrm_net_exit(struct net *net)
3084 {
3085 	flow_cache_fini(net);
3086 	xfrm_sysctl_fini(net);
3087 	xfrm_policy_fini(net);
3088 	xfrm_state_fini(net);
3089 	xfrm_statistics_fini(net);
3090 }
3091 
3092 static struct pernet_operations __net_initdata xfrm_net_ops = {
3093 	.init = xfrm_net_init,
3094 	.exit = xfrm_net_exit,
3095 };
3096 
3097 void __init xfrm_init(void)
3098 {
3099 	register_pernet_subsys(&xfrm_net_ops);
3100 	xfrm_input_init();
3101 }
3102 
3103 #ifdef CONFIG_AUDITSYSCALL
3104 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3105 					 struct audit_buffer *audit_buf)
3106 {
3107 	struct xfrm_sec_ctx *ctx = xp->security;
3108 	struct xfrm_selector *sel = &xp->selector;
3109 
3110 	if (ctx)
3111 		audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3112 				 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3113 
3114 	switch (sel->family) {
3115 	case AF_INET:
3116 		audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3117 		if (sel->prefixlen_s != 32)
3118 			audit_log_format(audit_buf, " src_prefixlen=%d",
3119 					 sel->prefixlen_s);
3120 		audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3121 		if (sel->prefixlen_d != 32)
3122 			audit_log_format(audit_buf, " dst_prefixlen=%d",
3123 					 sel->prefixlen_d);
3124 		break;
3125 	case AF_INET6:
3126 		audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3127 		if (sel->prefixlen_s != 128)
3128 			audit_log_format(audit_buf, " src_prefixlen=%d",
3129 					 sel->prefixlen_s);
3130 		audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3131 		if (sel->prefixlen_d != 128)
3132 			audit_log_format(audit_buf, " dst_prefixlen=%d",
3133 					 sel->prefixlen_d);
3134 		break;
3135 	}
3136 }
3137 
3138 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3139 {
3140 	struct audit_buffer *audit_buf;
3141 
3142 	audit_buf = xfrm_audit_start("SPD-add");
3143 	if (audit_buf == NULL)
3144 		return;
3145 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3146 	audit_log_format(audit_buf, " res=%u", result);
3147 	xfrm_audit_common_policyinfo(xp, audit_buf);
3148 	audit_log_end(audit_buf);
3149 }
3150 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3151 
3152 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3153 			      bool task_valid)
3154 {
3155 	struct audit_buffer *audit_buf;
3156 
3157 	audit_buf = xfrm_audit_start("SPD-delete");
3158 	if (audit_buf == NULL)
3159 		return;
3160 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3161 	audit_log_format(audit_buf, " res=%u", result);
3162 	xfrm_audit_common_policyinfo(xp, audit_buf);
3163 	audit_log_end(audit_buf);
3164 }
3165 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3166 #endif
3167 
3168 #ifdef CONFIG_XFRM_MIGRATE
3169 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3170 					const struct xfrm_selector *sel_tgt)
3171 {
3172 	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3173 		if (sel_tgt->family == sel_cmp->family &&
3174 		    xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3175 				    sel_cmp->family) &&
3176 		    xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3177 				    sel_cmp->family) &&
3178 		    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3179 		    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3180 			return true;
3181 		}
3182 	} else {
3183 		if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3184 			return true;
3185 		}
3186 	}
3187 	return false;
3188 }
3189 
3190 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3191 						    u8 dir, u8 type, struct net *net)
3192 {
3193 	struct xfrm_policy *pol, *ret = NULL;
3194 	struct hlist_head *chain;
3195 	u32 priority = ~0U;
3196 
3197 	read_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME*/
3198 	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3199 	hlist_for_each_entry(pol, chain, bydst) {
3200 		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3201 		    pol->type == type) {
3202 			ret = pol;
3203 			priority = ret->priority;
3204 			break;
3205 		}
3206 	}
3207 	chain = &net->xfrm.policy_inexact[dir];
3208 	hlist_for_each_entry(pol, chain, bydst) {
3209 		if ((pol->priority >= priority) && ret)
3210 			break;
3211 
3212 		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3213 		    pol->type == type) {
3214 			ret = pol;
3215 			break;
3216 		}
3217 	}
3218 
3219 	xfrm_pol_hold(ret);
3220 
3221 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
3222 
3223 	return ret;
3224 }
3225 
3226 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3227 {
3228 	int match = 0;
3229 
3230 	if (t->mode == m->mode && t->id.proto == m->proto &&
3231 	    (m->reqid == 0 || t->reqid == m->reqid)) {
3232 		switch (t->mode) {
3233 		case XFRM_MODE_TUNNEL:
3234 		case XFRM_MODE_BEET:
3235 			if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3236 					    m->old_family) &&
3237 			    xfrm_addr_equal(&t->saddr, &m->old_saddr,
3238 					    m->old_family)) {
3239 				match = 1;
3240 			}
3241 			break;
3242 		case XFRM_MODE_TRANSPORT:
3243 			/* in case of transport mode, template does not store
3244 			   any IP addresses, hence we just compare mode and
3245 			   protocol */
3246 			match = 1;
3247 			break;
3248 		default:
3249 			break;
3250 		}
3251 	}
3252 	return match;
3253 }
3254 
3255 /* update endpoint address(es) of template(s) */
3256 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3257 			       struct xfrm_migrate *m, int num_migrate)
3258 {
3259 	struct xfrm_migrate *mp;
3260 	int i, j, n = 0;
3261 
3262 	write_lock_bh(&pol->lock);
3263 	if (unlikely(pol->walk.dead)) {
3264 		/* target policy has been deleted */
3265 		write_unlock_bh(&pol->lock);
3266 		return -ENOENT;
3267 	}
3268 
3269 	for (i = 0; i < pol->xfrm_nr; i++) {
3270 		for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3271 			if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3272 				continue;
3273 			n++;
3274 			if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3275 			    pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3276 				continue;
3277 			/* update endpoints */
3278 			memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3279 			       sizeof(pol->xfrm_vec[i].id.daddr));
3280 			memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3281 			       sizeof(pol->xfrm_vec[i].saddr));
3282 			pol->xfrm_vec[i].encap_family = mp->new_family;
3283 			/* flush bundles */
3284 			atomic_inc(&pol->genid);
3285 		}
3286 	}
3287 
3288 	write_unlock_bh(&pol->lock);
3289 
3290 	if (!n)
3291 		return -ENODATA;
3292 
3293 	return 0;
3294 }
3295 
3296 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3297 {
3298 	int i, j;
3299 
3300 	if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3301 		return -EINVAL;
3302 
3303 	for (i = 0; i < num_migrate; i++) {
3304 		if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3305 				    m[i].old_family) &&
3306 		    xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3307 				    m[i].old_family))
3308 			return -EINVAL;
3309 		if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3310 		    xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3311 			return -EINVAL;
3312 
3313 		/* check if there is any duplicated entry */
3314 		for (j = i + 1; j < num_migrate; j++) {
3315 			if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3316 				    sizeof(m[i].old_daddr)) &&
3317 			    !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3318 				    sizeof(m[i].old_saddr)) &&
3319 			    m[i].proto == m[j].proto &&
3320 			    m[i].mode == m[j].mode &&
3321 			    m[i].reqid == m[j].reqid &&
3322 			    m[i].old_family == m[j].old_family)
3323 				return -EINVAL;
3324 		}
3325 	}
3326 
3327 	return 0;
3328 }
3329 
3330 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3331 		 struct xfrm_migrate *m, int num_migrate,
3332 		 struct xfrm_kmaddress *k, struct net *net)
3333 {
3334 	int i, err, nx_cur = 0, nx_new = 0;
3335 	struct xfrm_policy *pol = NULL;
3336 	struct xfrm_state *x, *xc;
3337 	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3338 	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3339 	struct xfrm_migrate *mp;
3340 
3341 	if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3342 		goto out;
3343 
3344 	/* Stage 1 - find policy */
3345 	if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3346 		err = -ENOENT;
3347 		goto out;
3348 	}
3349 
3350 	/* Stage 2 - find and update state(s) */
3351 	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3352 		if ((x = xfrm_migrate_state_find(mp, net))) {
3353 			x_cur[nx_cur] = x;
3354 			nx_cur++;
3355 			if ((xc = xfrm_state_migrate(x, mp))) {
3356 				x_new[nx_new] = xc;
3357 				nx_new++;
3358 			} else {
3359 				err = -ENODATA;
3360 				goto restore_state;
3361 			}
3362 		}
3363 	}
3364 
3365 	/* Stage 3 - update policy */
3366 	if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3367 		goto restore_state;
3368 
3369 	/* Stage 4 - delete old state(s) */
3370 	if (nx_cur) {
3371 		xfrm_states_put(x_cur, nx_cur);
3372 		xfrm_states_delete(x_cur, nx_cur);
3373 	}
3374 
3375 	/* Stage 5 - announce */
3376 	km_migrate(sel, dir, type, m, num_migrate, k);
3377 
3378 	xfrm_pol_put(pol);
3379 
3380 	return 0;
3381 out:
3382 	return err;
3383 
3384 restore_state:
3385 	if (pol)
3386 		xfrm_pol_put(pol);
3387 	if (nx_cur)
3388 		xfrm_states_put(x_cur, nx_cur);
3389 	if (nx_new)
3390 		xfrm_states_delete(x_new, nx_new);
3391 
3392 	return err;
3393 }
3394 EXPORT_SYMBOL(xfrm_migrate);
3395 #endif
3396