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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * xfrm_policy.c
4 *
5 * Changes:
6 * Mitsuru KANDA @USAGI
7 * Kazunori MIYAZAWA @USAGI
8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
9 * IPv6 support
10 * Kazunori MIYAZAWA @USAGI
11 * YOSHIFUJI Hideaki
12 * Split up af-specific portion
13 * Derek Atkins <derek@ihtfp.com> Add the post_input processor
14 *
15 */
16
17#include <linux/err.h>
18#include <linux/slab.h>
19#include <linux/kmod.h>
20#include <linux/list.h>
21#include <linux/spinlock.h>
22#include <linux/workqueue.h>
23#include <linux/notifier.h>
24#include <linux/netdevice.h>
25#include <linux/netfilter.h>
26#include <linux/module.h>
27#include <linux/cache.h>
28#include <linux/cpu.h>
29#include <linux/audit.h>
30#include <linux/rhashtable.h>
31#include <linux/if_tunnel.h>
32#include <linux/icmp.h>
33#include <net/dst.h>
34#include <net/flow.h>
35#include <net/inet_ecn.h>
36#include <net/xfrm.h>
37#include <net/ip.h>
38#include <net/gre.h>
39#if IS_ENABLED(CONFIG_IPV6_MIP6)
40#include <net/mip6.h>
41#endif
42#ifdef CONFIG_XFRM_STATISTICS
43#include <net/snmp.h>
44#endif
45#ifdef CONFIG_XFRM_ESPINTCP
46#include <net/espintcp.h>
47#endif
48#include <net/inet_dscp.h>
49
50#include "xfrm_hash.h"
51
52#define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
53#define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
54#define XFRM_MAX_QUEUE_LEN 100
55
56struct xfrm_flo {
57 struct dst_entry *dst_orig;
58 u8 flags;
59};
60
61/* prefixes smaller than this are stored in lists, not trees. */
62#define INEXACT_PREFIXLEN_IPV4 16
63#define INEXACT_PREFIXLEN_IPV6 48
64
65struct xfrm_pol_inexact_node {
66 struct rb_node node;
67 union {
68 xfrm_address_t addr;
69 struct rcu_head rcu;
70 };
71 u8 prefixlen;
72
73 struct rb_root root;
74
75 /* the policies matching this node, can be empty list */
76 struct hlist_head hhead;
77};
78
79/* xfrm inexact policy search tree:
80 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
81 * |
82 * +---- root_d: sorted by daddr:prefix
83 * | |
84 * | xfrm_pol_inexact_node
85 * | |
86 * | +- root: sorted by saddr/prefix
87 * | | |
88 * | | xfrm_pol_inexact_node
89 * | | |
90 * | | + root: unused
91 * | | |
92 * | | + hhead: saddr:daddr policies
93 * | |
94 * | +- coarse policies and all any:daddr policies
95 * |
96 * +---- root_s: sorted by saddr:prefix
97 * | |
98 * | xfrm_pol_inexact_node
99 * | |
100 * | + root: unused
101 * | |
102 * | + hhead: saddr:any policies
103 * |
104 * +---- coarse policies and all any:any policies
105 *
106 * Lookups return four candidate lists:
107 * 1. any:any list from top-level xfrm_pol_inexact_bin
108 * 2. any:daddr list from daddr tree
109 * 3. saddr:daddr list from 2nd level daddr tree
110 * 4. saddr:any list from saddr tree
111 *
112 * This result set then needs to be searched for the policy with
113 * the lowest priority. If two candidates have the same priority, the
114 * struct xfrm_policy pos member with the lower number is used.
115 *
116 * This replicates previous single-list-search algorithm which would
117 * return first matching policy in the (ordered-by-priority) list.
118 */
119
120struct xfrm_pol_inexact_key {
121 possible_net_t net;
122 u32 if_id;
123 u16 family;
124 u8 dir, type;
125};
126
127struct xfrm_pol_inexact_bin {
128 struct xfrm_pol_inexact_key k;
129 struct rhash_head head;
130 /* list containing '*:*' policies */
131 struct hlist_head hhead;
132
133 seqcount_spinlock_t count;
134 /* tree sorted by daddr/prefix */
135 struct rb_root root_d;
136
137 /* tree sorted by saddr/prefix */
138 struct rb_root root_s;
139
140 /* slow path below */
141 struct list_head inexact_bins;
142 struct rcu_head rcu;
143};
144
145enum xfrm_pol_inexact_candidate_type {
146 XFRM_POL_CAND_BOTH,
147 XFRM_POL_CAND_SADDR,
148 XFRM_POL_CAND_DADDR,
149 XFRM_POL_CAND_ANY,
150
151 XFRM_POL_CAND_MAX,
152};
153
154struct xfrm_pol_inexact_candidates {
155 struct hlist_head *res[XFRM_POL_CAND_MAX];
156};
157
158struct xfrm_flow_keys {
159 struct flow_dissector_key_basic basic;
160 struct flow_dissector_key_control control;
161 union {
162 struct flow_dissector_key_ipv4_addrs ipv4;
163 struct flow_dissector_key_ipv6_addrs ipv6;
164 } addrs;
165 struct flow_dissector_key_ip ip;
166 struct flow_dissector_key_icmp icmp;
167 struct flow_dissector_key_ports ports;
168 struct flow_dissector_key_keyid gre;
169};
170
171static struct flow_dissector xfrm_session_dissector __ro_after_init;
172
173static DEFINE_SPINLOCK(xfrm_if_cb_lock);
174static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
175
176static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
177static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
178 __read_mostly;
179
180static struct kmem_cache *xfrm_dst_cache __ro_after_init;
181
182static struct rhashtable xfrm_policy_inexact_table;
183static const struct rhashtable_params xfrm_pol_inexact_params;
184
185static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
186static int stale_bundle(struct dst_entry *dst);
187static int xfrm_bundle_ok(struct xfrm_dst *xdst);
188static void xfrm_policy_queue_process(struct timer_list *t);
189
190static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
191static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
192 int dir);
193
194static struct xfrm_pol_inexact_bin *
195xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
196 u32 if_id);
197
198static struct xfrm_pol_inexact_bin *
199xfrm_policy_inexact_lookup_rcu(struct net *net,
200 u8 type, u16 family, u8 dir, u32 if_id);
201static struct xfrm_policy *
202xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
203 bool excl);
204
205static bool
206xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
207 struct xfrm_pol_inexact_bin *b,
208 const xfrm_address_t *saddr,
209 const xfrm_address_t *daddr);
210
211static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
212{
213 return refcount_inc_not_zero(&policy->refcnt);
214}
215
216static inline bool
217__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
218{
219 const struct flowi4 *fl4 = &fl->u.ip4;
220
221 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
222 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
223 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
224 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
225 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
226 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
227}
228
229static inline bool
230__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
231{
232 const struct flowi6 *fl6 = &fl->u.ip6;
233
234 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
235 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
236 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
237 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
238 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
239 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
240}
241
242bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
243 unsigned short family)
244{
245 switch (family) {
246 case AF_INET:
247 return __xfrm4_selector_match(sel, fl);
248 case AF_INET6:
249 return __xfrm6_selector_match(sel, fl);
250 }
251 return false;
252}
253
254static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
255{
256 const struct xfrm_policy_afinfo *afinfo;
257
258 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
259 return NULL;
260 rcu_read_lock();
261 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
262 if (unlikely(!afinfo))
263 rcu_read_unlock();
264 return afinfo;
265}
266
267/* Called with rcu_read_lock(). */
268static const struct xfrm_if_cb *xfrm_if_get_cb(void)
269{
270 return rcu_dereference(xfrm_if_cb);
271}
272
273struct dst_entry *__xfrm_dst_lookup(int family,
274 const struct xfrm_dst_lookup_params *params)
275{
276 const struct xfrm_policy_afinfo *afinfo;
277 struct dst_entry *dst;
278
279 afinfo = xfrm_policy_get_afinfo(family);
280 if (unlikely(afinfo == NULL))
281 return ERR_PTR(-EAFNOSUPPORT);
282
283 dst = afinfo->dst_lookup(params);
284
285 rcu_read_unlock();
286
287 return dst;
288}
289EXPORT_SYMBOL(__xfrm_dst_lookup);
290
291static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
292 dscp_t dscp, int oif,
293 xfrm_address_t *prev_saddr,
294 xfrm_address_t *prev_daddr,
295 int family, u32 mark)
296{
297 struct xfrm_dst_lookup_params params;
298 struct net *net = xs_net(x);
299 xfrm_address_t *saddr = &x->props.saddr;
300 xfrm_address_t *daddr = &x->id.daddr;
301 struct dst_entry *dst;
302
303 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
304 saddr = x->coaddr;
305 daddr = prev_daddr;
306 }
307 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
308 saddr = prev_saddr;
309 daddr = x->coaddr;
310 }
311
312 params.net = net;
313 params.saddr = saddr;
314 params.daddr = daddr;
315 params.dscp = dscp;
316 params.oif = oif;
317 params.mark = mark;
318 params.ipproto = x->id.proto;
319 if (x->encap) {
320 switch (x->encap->encap_type) {
321 case UDP_ENCAP_ESPINUDP:
322 params.ipproto = IPPROTO_UDP;
323 params.uli.ports.sport = x->encap->encap_sport;
324 params.uli.ports.dport = x->encap->encap_dport;
325 break;
326 case TCP_ENCAP_ESPINTCP:
327 params.ipproto = IPPROTO_TCP;
328 params.uli.ports.sport = x->encap->encap_sport;
329 params.uli.ports.dport = x->encap->encap_dport;
330 break;
331 }
332 }
333
334 dst = __xfrm_dst_lookup(family, ¶ms);
335
336 if (!IS_ERR(dst)) {
337 if (prev_saddr != saddr)
338 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
339 if (prev_daddr != daddr)
340 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
341 }
342
343 return dst;
344}
345
346static inline unsigned long make_jiffies(long secs)
347{
348 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
349 return MAX_SCHEDULE_TIMEOUT-1;
350 else
351 return secs*HZ;
352}
353
354static void xfrm_policy_timer(struct timer_list *t)
355{
356 struct xfrm_policy *xp = from_timer(xp, t, timer);
357 time64_t now = ktime_get_real_seconds();
358 time64_t next = TIME64_MAX;
359 int warn = 0;
360 int dir;
361
362 read_lock(&xp->lock);
363
364 if (unlikely(xp->walk.dead))
365 goto out;
366
367 dir = xfrm_policy_id2dir(xp->index);
368
369 if (xp->lft.hard_add_expires_seconds) {
370 time64_t tmo = xp->lft.hard_add_expires_seconds +
371 xp->curlft.add_time - now;
372 if (tmo <= 0)
373 goto expired;
374 if (tmo < next)
375 next = tmo;
376 }
377 if (xp->lft.hard_use_expires_seconds) {
378 time64_t tmo = xp->lft.hard_use_expires_seconds +
379 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
380 if (tmo <= 0)
381 goto expired;
382 if (tmo < next)
383 next = tmo;
384 }
385 if (xp->lft.soft_add_expires_seconds) {
386 time64_t tmo = xp->lft.soft_add_expires_seconds +
387 xp->curlft.add_time - now;
388 if (tmo <= 0) {
389 warn = 1;
390 tmo = XFRM_KM_TIMEOUT;
391 }
392 if (tmo < next)
393 next = tmo;
394 }
395 if (xp->lft.soft_use_expires_seconds) {
396 time64_t tmo = xp->lft.soft_use_expires_seconds +
397 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
398 if (tmo <= 0) {
399 warn = 1;
400 tmo = XFRM_KM_TIMEOUT;
401 }
402 if (tmo < next)
403 next = tmo;
404 }
405
406 if (warn)
407 km_policy_expired(xp, dir, 0, 0);
408 if (next != TIME64_MAX &&
409 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
410 xfrm_pol_hold(xp);
411
412out:
413 read_unlock(&xp->lock);
414 xfrm_pol_put(xp);
415 return;
416
417expired:
418 read_unlock(&xp->lock);
419 if (!xfrm_policy_delete(xp, dir))
420 km_policy_expired(xp, dir, 1, 0);
421 xfrm_pol_put(xp);
422}
423
424/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
425 * SPD calls.
426 */
427
428struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
429{
430 struct xfrm_policy *policy;
431
432 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
433
434 if (policy) {
435 write_pnet(&policy->xp_net, net);
436 INIT_LIST_HEAD(&policy->walk.all);
437 INIT_HLIST_HEAD(&policy->state_cache_list);
438 INIT_HLIST_NODE(&policy->bydst);
439 INIT_HLIST_NODE(&policy->byidx);
440 rwlock_init(&policy->lock);
441 refcount_set(&policy->refcnt, 1);
442 skb_queue_head_init(&policy->polq.hold_queue);
443 timer_setup(&policy->timer, xfrm_policy_timer, 0);
444 timer_setup(&policy->polq.hold_timer,
445 xfrm_policy_queue_process, 0);
446 }
447 return policy;
448}
449EXPORT_SYMBOL(xfrm_policy_alloc);
450
451static void xfrm_policy_destroy_rcu(struct rcu_head *head)
452{
453 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
454
455 security_xfrm_policy_free(policy->security);
456 kfree(policy);
457}
458
459/* Destroy xfrm_policy: descendant resources must be released to this moment. */
460
461void xfrm_policy_destroy(struct xfrm_policy *policy)
462{
463 BUG_ON(!policy->walk.dead);
464
465 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
466 BUG();
467
468 xfrm_dev_policy_free(policy);
469 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
470}
471EXPORT_SYMBOL(xfrm_policy_destroy);
472
473/* Rule must be locked. Release descendant resources, announce
474 * entry dead. The rule must be unlinked from lists to the moment.
475 */
476
477static void xfrm_policy_kill(struct xfrm_policy *policy)
478{
479 struct net *net = xp_net(policy);
480 struct xfrm_state *x;
481
482 xfrm_dev_policy_delete(policy);
483
484 write_lock_bh(&policy->lock);
485 policy->walk.dead = 1;
486 write_unlock_bh(&policy->lock);
487
488 atomic_inc(&policy->genid);
489
490 if (del_timer(&policy->polq.hold_timer))
491 xfrm_pol_put(policy);
492 skb_queue_purge(&policy->polq.hold_queue);
493
494 if (del_timer(&policy->timer))
495 xfrm_pol_put(policy);
496
497 /* XXX: Flush state cache */
498 spin_lock_bh(&net->xfrm.xfrm_state_lock);
499 hlist_for_each_entry_rcu(x, &policy->state_cache_list, state_cache) {
500 hlist_del_init_rcu(&x->state_cache);
501 }
502 spin_unlock_bh(&net->xfrm.xfrm_state_lock);
503
504 xfrm_pol_put(policy);
505}
506
507static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
508
509static inline unsigned int idx_hash(struct net *net, u32 index)
510{
511 return __idx_hash(index, net->xfrm.policy_idx_hmask);
512}
513
514/* calculate policy hash thresholds */
515static void __get_hash_thresh(struct net *net,
516 unsigned short family, int dir,
517 u8 *dbits, u8 *sbits)
518{
519 switch (family) {
520 case AF_INET:
521 *dbits = net->xfrm.policy_bydst[dir].dbits4;
522 *sbits = net->xfrm.policy_bydst[dir].sbits4;
523 break;
524
525 case AF_INET6:
526 *dbits = net->xfrm.policy_bydst[dir].dbits6;
527 *sbits = net->xfrm.policy_bydst[dir].sbits6;
528 break;
529
530 default:
531 *dbits = 0;
532 *sbits = 0;
533 }
534}
535
536static struct hlist_head *policy_hash_bysel(struct net *net,
537 const struct xfrm_selector *sel,
538 unsigned short family, int dir)
539{
540 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
541 unsigned int hash;
542 u8 dbits;
543 u8 sbits;
544
545 __get_hash_thresh(net, family, dir, &dbits, &sbits);
546 hash = __sel_hash(sel, family, hmask, dbits, sbits);
547
548 if (hash == hmask + 1)
549 return NULL;
550
551 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
552 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
553}
554
555static struct hlist_head *policy_hash_direct(struct net *net,
556 const xfrm_address_t *daddr,
557 const xfrm_address_t *saddr,
558 unsigned short family, int dir)
559{
560 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
561 unsigned int hash;
562 u8 dbits;
563 u8 sbits;
564
565 __get_hash_thresh(net, family, dir, &dbits, &sbits);
566 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
567
568 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
569 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
570}
571
572static void xfrm_dst_hash_transfer(struct net *net,
573 struct hlist_head *list,
574 struct hlist_head *ndsttable,
575 unsigned int nhashmask,
576 int dir)
577{
578 struct hlist_node *tmp, *entry0 = NULL;
579 struct xfrm_policy *pol;
580 unsigned int h0 = 0;
581 u8 dbits;
582 u8 sbits;
583
584redo:
585 hlist_for_each_entry_safe(pol, tmp, list, bydst) {
586 unsigned int h;
587
588 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
589 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
590 pol->family, nhashmask, dbits, sbits);
591 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) {
592 hlist_del_rcu(&pol->bydst);
593 hlist_add_head_rcu(&pol->bydst, ndsttable + h);
594 h0 = h;
595 } else {
596 if (h != h0)
597 continue;
598 hlist_del_rcu(&pol->bydst);
599 hlist_add_behind_rcu(&pol->bydst, entry0);
600 }
601 entry0 = &pol->bydst;
602 }
603 if (!hlist_empty(list)) {
604 entry0 = NULL;
605 goto redo;
606 }
607}
608
609static void xfrm_idx_hash_transfer(struct hlist_head *list,
610 struct hlist_head *nidxtable,
611 unsigned int nhashmask)
612{
613 struct hlist_node *tmp;
614 struct xfrm_policy *pol;
615
616 hlist_for_each_entry_safe(pol, tmp, list, byidx) {
617 unsigned int h;
618
619 h = __idx_hash(pol->index, nhashmask);
620 hlist_add_head(&pol->byidx, nidxtable+h);
621 }
622}
623
624static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
625{
626 return ((old_hmask + 1) << 1) - 1;
627}
628
629static void xfrm_bydst_resize(struct net *net, int dir)
630{
631 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
632 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
633 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
634 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
635 struct hlist_head *odst;
636 int i;
637
638 if (!ndst)
639 return;
640
641 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
642 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
643
644 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
645 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
646
647 for (i = hmask; i >= 0; i--)
648 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
649
650 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
651 net->xfrm.policy_bydst[dir].hmask = nhashmask;
652
653 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
654 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
655
656 synchronize_rcu();
657
658 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
659}
660
661static void xfrm_byidx_resize(struct net *net)
662{
663 unsigned int hmask = net->xfrm.policy_idx_hmask;
664 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
665 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
666 struct hlist_head *oidx = net->xfrm.policy_byidx;
667 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
668 int i;
669
670 if (!nidx)
671 return;
672
673 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
674
675 for (i = hmask; i >= 0; i--)
676 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
677
678 net->xfrm.policy_byidx = nidx;
679 net->xfrm.policy_idx_hmask = nhashmask;
680
681 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
682
683 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
684}
685
686static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
687{
688 unsigned int cnt = net->xfrm.policy_count[dir];
689 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
690
691 if (total)
692 *total += cnt;
693
694 if ((hmask + 1) < xfrm_policy_hashmax &&
695 cnt > hmask)
696 return 1;
697
698 return 0;
699}
700
701static inline int xfrm_byidx_should_resize(struct net *net, int total)
702{
703 unsigned int hmask = net->xfrm.policy_idx_hmask;
704
705 if ((hmask + 1) < xfrm_policy_hashmax &&
706 total > hmask)
707 return 1;
708
709 return 0;
710}
711
712void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
713{
714 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
715 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
716 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
717 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
718 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
719 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
720 si->spdhcnt = net->xfrm.policy_idx_hmask;
721 si->spdhmcnt = xfrm_policy_hashmax;
722}
723EXPORT_SYMBOL(xfrm_spd_getinfo);
724
725static DEFINE_MUTEX(hash_resize_mutex);
726static void xfrm_hash_resize(struct work_struct *work)
727{
728 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
729 int dir, total;
730
731 mutex_lock(&hash_resize_mutex);
732
733 total = 0;
734 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
735 if (xfrm_bydst_should_resize(net, dir, &total))
736 xfrm_bydst_resize(net, dir);
737 }
738 if (xfrm_byidx_should_resize(net, total))
739 xfrm_byidx_resize(net);
740
741 mutex_unlock(&hash_resize_mutex);
742}
743
744/* Make sure *pol can be inserted into fastbin.
745 * Useful to check that later insert requests will be successful
746 * (provided xfrm_policy_lock is held throughout).
747 */
748static struct xfrm_pol_inexact_bin *
749xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
750{
751 struct xfrm_pol_inexact_bin *bin, *prev;
752 struct xfrm_pol_inexact_key k = {
753 .family = pol->family,
754 .type = pol->type,
755 .dir = dir,
756 .if_id = pol->if_id,
757 };
758 struct net *net = xp_net(pol);
759
760 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
761
762 write_pnet(&k.net, net);
763 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
764 xfrm_pol_inexact_params);
765 if (bin)
766 return bin;
767
768 bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
769 if (!bin)
770 return NULL;
771
772 bin->k = k;
773 INIT_HLIST_HEAD(&bin->hhead);
774 bin->root_d = RB_ROOT;
775 bin->root_s = RB_ROOT;
776 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
777
778 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
779 &bin->k, &bin->head,
780 xfrm_pol_inexact_params);
781 if (!prev) {
782 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
783 return bin;
784 }
785
786 kfree(bin);
787
788 return IS_ERR(prev) ? NULL : prev;
789}
790
791static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
792 int family, u8 prefixlen)
793{
794 if (xfrm_addr_any(addr, family))
795 return true;
796
797 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
798 return true;
799
800 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
801 return true;
802
803 return false;
804}
805
806static bool
807xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
808{
809 const xfrm_address_t *addr;
810 bool saddr_any, daddr_any;
811 u8 prefixlen;
812
813 addr = &policy->selector.saddr;
814 prefixlen = policy->selector.prefixlen_s;
815
816 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
817 policy->family,
818 prefixlen);
819 addr = &policy->selector.daddr;
820 prefixlen = policy->selector.prefixlen_d;
821 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
822 policy->family,
823 prefixlen);
824 return saddr_any && daddr_any;
825}
826
827static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
828 const xfrm_address_t *addr, u8 prefixlen)
829{
830 node->addr = *addr;
831 node->prefixlen = prefixlen;
832}
833
834static struct xfrm_pol_inexact_node *
835xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
836{
837 struct xfrm_pol_inexact_node *node;
838
839 node = kzalloc(sizeof(*node), GFP_ATOMIC);
840 if (node)
841 xfrm_pol_inexact_node_init(node, addr, prefixlen);
842
843 return node;
844}
845
846static int xfrm_policy_addr_delta(const xfrm_address_t *a,
847 const xfrm_address_t *b,
848 u8 prefixlen, u16 family)
849{
850 u32 ma, mb, mask;
851 unsigned int pdw, pbi;
852 int delta = 0;
853
854 switch (family) {
855 case AF_INET:
856 if (prefixlen == 0)
857 return 0;
858 mask = ~0U << (32 - prefixlen);
859 ma = ntohl(a->a4) & mask;
860 mb = ntohl(b->a4) & mask;
861 if (ma < mb)
862 delta = -1;
863 else if (ma > mb)
864 delta = 1;
865 break;
866 case AF_INET6:
867 pdw = prefixlen >> 5;
868 pbi = prefixlen & 0x1f;
869
870 if (pdw) {
871 delta = memcmp(a->a6, b->a6, pdw << 2);
872 if (delta)
873 return delta;
874 }
875 if (pbi) {
876 mask = ~0U << (32 - pbi);
877 ma = ntohl(a->a6[pdw]) & mask;
878 mb = ntohl(b->a6[pdw]) & mask;
879 if (ma < mb)
880 delta = -1;
881 else if (ma > mb)
882 delta = 1;
883 }
884 break;
885 default:
886 break;
887 }
888
889 return delta;
890}
891
892static void xfrm_policy_inexact_list_reinsert(struct net *net,
893 struct xfrm_pol_inexact_node *n,
894 u16 family)
895{
896 unsigned int matched_s, matched_d;
897 struct xfrm_policy *policy, *p;
898
899 matched_s = 0;
900 matched_d = 0;
901
902 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
903 struct hlist_node *newpos = NULL;
904 bool matches_s, matches_d;
905
906 if (policy->walk.dead || !policy->bydst_reinsert)
907 continue;
908
909 WARN_ON_ONCE(policy->family != family);
910
911 policy->bydst_reinsert = false;
912 hlist_for_each_entry(p, &n->hhead, bydst) {
913 if (policy->priority > p->priority)
914 newpos = &p->bydst;
915 else if (policy->priority == p->priority &&
916 policy->pos > p->pos)
917 newpos = &p->bydst;
918 else
919 break;
920 }
921
922 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
923 hlist_add_behind_rcu(&policy->bydst, newpos);
924 else
925 hlist_add_head_rcu(&policy->bydst, &n->hhead);
926
927 /* paranoia checks follow.
928 * Check that the reinserted policy matches at least
929 * saddr or daddr for current node prefix.
930 *
931 * Matching both is fine, matching saddr in one policy
932 * (but not daddr) and then matching only daddr in another
933 * is a bug.
934 */
935 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
936 &n->addr,
937 n->prefixlen,
938 family) == 0;
939 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
940 &n->addr,
941 n->prefixlen,
942 family) == 0;
943 if (matches_s && matches_d)
944 continue;
945
946 WARN_ON_ONCE(!matches_s && !matches_d);
947 if (matches_s)
948 matched_s++;
949 if (matches_d)
950 matched_d++;
951 WARN_ON_ONCE(matched_s && matched_d);
952 }
953}
954
955static void xfrm_policy_inexact_node_reinsert(struct net *net,
956 struct xfrm_pol_inexact_node *n,
957 struct rb_root *new,
958 u16 family)
959{
960 struct xfrm_pol_inexact_node *node;
961 struct rb_node **p, *parent;
962
963 /* we should not have another subtree here */
964 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
965restart:
966 parent = NULL;
967 p = &new->rb_node;
968 while (*p) {
969 u8 prefixlen;
970 int delta;
971
972 parent = *p;
973 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
974
975 prefixlen = min(node->prefixlen, n->prefixlen);
976
977 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
978 prefixlen, family);
979 if (delta < 0) {
980 p = &parent->rb_left;
981 } else if (delta > 0) {
982 p = &parent->rb_right;
983 } else {
984 bool same_prefixlen = node->prefixlen == n->prefixlen;
985 struct xfrm_policy *tmp;
986
987 hlist_for_each_entry(tmp, &n->hhead, bydst) {
988 tmp->bydst_reinsert = true;
989 hlist_del_rcu(&tmp->bydst);
990 }
991
992 node->prefixlen = prefixlen;
993
994 xfrm_policy_inexact_list_reinsert(net, node, family);
995
996 if (same_prefixlen) {
997 kfree_rcu(n, rcu);
998 return;
999 }
1000
1001 rb_erase(*p, new);
1002 kfree_rcu(n, rcu);
1003 n = node;
1004 goto restart;
1005 }
1006 }
1007
1008 rb_link_node_rcu(&n->node, parent, p);
1009 rb_insert_color(&n->node, new);
1010}
1011
1012/* merge nodes v and n */
1013static void xfrm_policy_inexact_node_merge(struct net *net,
1014 struct xfrm_pol_inexact_node *v,
1015 struct xfrm_pol_inexact_node *n,
1016 u16 family)
1017{
1018 struct xfrm_pol_inexact_node *node;
1019 struct xfrm_policy *tmp;
1020 struct rb_node *rnode;
1021
1022 /* To-be-merged node v has a subtree.
1023 *
1024 * Dismantle it and insert its nodes to n->root.
1025 */
1026 while ((rnode = rb_first(&v->root)) != NULL) {
1027 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
1028 rb_erase(&node->node, &v->root);
1029 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
1030 family);
1031 }
1032
1033 hlist_for_each_entry(tmp, &v->hhead, bydst) {
1034 tmp->bydst_reinsert = true;
1035 hlist_del_rcu(&tmp->bydst);
1036 }
1037
1038 xfrm_policy_inexact_list_reinsert(net, n, family);
1039}
1040
1041static struct xfrm_pol_inexact_node *
1042xfrm_policy_inexact_insert_node(struct net *net,
1043 struct rb_root *root,
1044 xfrm_address_t *addr,
1045 u16 family, u8 prefixlen, u8 dir)
1046{
1047 struct xfrm_pol_inexact_node *cached = NULL;
1048 struct rb_node **p, *parent = NULL;
1049 struct xfrm_pol_inexact_node *node;
1050
1051 p = &root->rb_node;
1052 while (*p) {
1053 int delta;
1054
1055 parent = *p;
1056 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
1057
1058 delta = xfrm_policy_addr_delta(addr, &node->addr,
1059 node->prefixlen,
1060 family);
1061 if (delta == 0 && prefixlen >= node->prefixlen) {
1062 WARN_ON_ONCE(cached); /* ipsec policies got lost */
1063 return node;
1064 }
1065
1066 if (delta < 0)
1067 p = &parent->rb_left;
1068 else
1069 p = &parent->rb_right;
1070
1071 if (prefixlen < node->prefixlen) {
1072 delta = xfrm_policy_addr_delta(addr, &node->addr,
1073 prefixlen,
1074 family);
1075 if (delta)
1076 continue;
1077
1078 /* This node is a subnet of the new prefix. It needs
1079 * to be removed and re-inserted with the smaller
1080 * prefix and all nodes that are now also covered
1081 * by the reduced prefixlen.
1082 */
1083 rb_erase(&node->node, root);
1084
1085 if (!cached) {
1086 xfrm_pol_inexact_node_init(node, addr,
1087 prefixlen);
1088 cached = node;
1089 } else {
1090 /* This node also falls within the new
1091 * prefixlen. Merge the to-be-reinserted
1092 * node and this one.
1093 */
1094 xfrm_policy_inexact_node_merge(net, node,
1095 cached, family);
1096 kfree_rcu(node, rcu);
1097 }
1098
1099 /* restart */
1100 p = &root->rb_node;
1101 parent = NULL;
1102 }
1103 }
1104
1105 node = cached;
1106 if (!node) {
1107 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1108 if (!node)
1109 return NULL;
1110 }
1111
1112 rb_link_node_rcu(&node->node, parent, p);
1113 rb_insert_color(&node->node, root);
1114
1115 return node;
1116}
1117
1118static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1119{
1120 struct xfrm_pol_inexact_node *node;
1121 struct rb_node *rn = rb_first(r);
1122
1123 while (rn) {
1124 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1125
1126 xfrm_policy_inexact_gc_tree(&node->root, rm);
1127 rn = rb_next(rn);
1128
1129 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1130 WARN_ON_ONCE(rm);
1131 continue;
1132 }
1133
1134 rb_erase(&node->node, r);
1135 kfree_rcu(node, rcu);
1136 }
1137}
1138
1139static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1140{
1141 write_seqcount_begin(&b->count);
1142 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1143 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1144 write_seqcount_end(&b->count);
1145
1146 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1147 !hlist_empty(&b->hhead)) {
1148 WARN_ON_ONCE(net_exit);
1149 return;
1150 }
1151
1152 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1153 xfrm_pol_inexact_params) == 0) {
1154 list_del(&b->inexact_bins);
1155 kfree_rcu(b, rcu);
1156 }
1157}
1158
1159static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1160{
1161 struct net *net = read_pnet(&b->k.net);
1162
1163 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1164 __xfrm_policy_inexact_prune_bin(b, false);
1165 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1166}
1167
1168static void __xfrm_policy_inexact_flush(struct net *net)
1169{
1170 struct xfrm_pol_inexact_bin *bin, *t;
1171
1172 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1173
1174 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1175 __xfrm_policy_inexact_prune_bin(bin, false);
1176}
1177
1178static struct hlist_head *
1179xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1180 struct xfrm_policy *policy, u8 dir)
1181{
1182 struct xfrm_pol_inexact_node *n;
1183 struct net *net;
1184
1185 net = xp_net(policy);
1186 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1187
1188 if (xfrm_policy_inexact_insert_use_any_list(policy))
1189 return &bin->hhead;
1190
1191 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1192 policy->family,
1193 policy->selector.prefixlen_d)) {
1194 write_seqcount_begin(&bin->count);
1195 n = xfrm_policy_inexact_insert_node(net,
1196 &bin->root_s,
1197 &policy->selector.saddr,
1198 policy->family,
1199 policy->selector.prefixlen_s,
1200 dir);
1201 write_seqcount_end(&bin->count);
1202 if (!n)
1203 return NULL;
1204
1205 return &n->hhead;
1206 }
1207
1208 /* daddr is fixed */
1209 write_seqcount_begin(&bin->count);
1210 n = xfrm_policy_inexact_insert_node(net,
1211 &bin->root_d,
1212 &policy->selector.daddr,
1213 policy->family,
1214 policy->selector.prefixlen_d, dir);
1215 write_seqcount_end(&bin->count);
1216 if (!n)
1217 return NULL;
1218
1219 /* saddr is wildcard */
1220 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1221 policy->family,
1222 policy->selector.prefixlen_s))
1223 return &n->hhead;
1224
1225 write_seqcount_begin(&bin->count);
1226 n = xfrm_policy_inexact_insert_node(net,
1227 &n->root,
1228 &policy->selector.saddr,
1229 policy->family,
1230 policy->selector.prefixlen_s, dir);
1231 write_seqcount_end(&bin->count);
1232 if (!n)
1233 return NULL;
1234
1235 return &n->hhead;
1236}
1237
1238static struct xfrm_policy *
1239xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1240{
1241 struct xfrm_pol_inexact_bin *bin;
1242 struct xfrm_policy *delpol;
1243 struct hlist_head *chain;
1244 struct net *net;
1245
1246 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1247 if (!bin)
1248 return ERR_PTR(-ENOMEM);
1249
1250 net = xp_net(policy);
1251 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1252
1253 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1254 if (!chain) {
1255 __xfrm_policy_inexact_prune_bin(bin, false);
1256 return ERR_PTR(-ENOMEM);
1257 }
1258
1259 delpol = xfrm_policy_insert_list(chain, policy, excl);
1260 if (delpol && excl) {
1261 __xfrm_policy_inexact_prune_bin(bin, false);
1262 return ERR_PTR(-EEXIST);
1263 }
1264
1265 if (delpol)
1266 __xfrm_policy_inexact_prune_bin(bin, false);
1267
1268 return delpol;
1269}
1270
1271static bool xfrm_policy_is_dead_or_sk(const struct xfrm_policy *policy)
1272{
1273 int dir;
1274
1275 if (policy->walk.dead)
1276 return true;
1277
1278 dir = xfrm_policy_id2dir(policy->index);
1279 return dir >= XFRM_POLICY_MAX;
1280}
1281
1282static void xfrm_hash_rebuild(struct work_struct *work)
1283{
1284 struct net *net = container_of(work, struct net,
1285 xfrm.policy_hthresh.work);
1286 struct xfrm_policy *pol;
1287 struct xfrm_policy *policy;
1288 struct hlist_head *chain;
1289 struct hlist_node *newpos;
1290 int dir;
1291 unsigned seq;
1292 u8 lbits4, rbits4, lbits6, rbits6;
1293
1294 mutex_lock(&hash_resize_mutex);
1295
1296 /* read selector prefixlen thresholds */
1297 do {
1298 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1299
1300 lbits4 = net->xfrm.policy_hthresh.lbits4;
1301 rbits4 = net->xfrm.policy_hthresh.rbits4;
1302 lbits6 = net->xfrm.policy_hthresh.lbits6;
1303 rbits6 = net->xfrm.policy_hthresh.rbits6;
1304 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1305
1306 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1307 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
1308
1309 /* make sure that we can insert the indirect policies again before
1310 * we start with destructive action.
1311 */
1312 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1313 struct xfrm_pol_inexact_bin *bin;
1314 u8 dbits, sbits;
1315
1316 if (xfrm_policy_is_dead_or_sk(policy))
1317 continue;
1318
1319 dir = xfrm_policy_id2dir(policy->index);
1320 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1321 if (policy->family == AF_INET) {
1322 dbits = rbits4;
1323 sbits = lbits4;
1324 } else {
1325 dbits = rbits6;
1326 sbits = lbits6;
1327 }
1328 } else {
1329 if (policy->family == AF_INET) {
1330 dbits = lbits4;
1331 sbits = rbits4;
1332 } else {
1333 dbits = lbits6;
1334 sbits = rbits6;
1335 }
1336 }
1337
1338 if (policy->selector.prefixlen_d < dbits ||
1339 policy->selector.prefixlen_s < sbits)
1340 continue;
1341
1342 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1343 if (!bin)
1344 goto out_unlock;
1345
1346 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1347 goto out_unlock;
1348 }
1349
1350 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1351 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1352 /* dir out => dst = remote, src = local */
1353 net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1354 net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1355 net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1356 net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1357 } else {
1358 /* dir in/fwd => dst = local, src = remote */
1359 net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1360 net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1361 net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1362 net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1363 }
1364 }
1365
1366 /* re-insert all policies by order of creation */
1367 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1368 if (xfrm_policy_is_dead_or_sk(policy))
1369 continue;
1370
1371 hlist_del_rcu(&policy->bydst);
1372
1373 newpos = NULL;
1374 dir = xfrm_policy_id2dir(policy->index);
1375 chain = policy_hash_bysel(net, &policy->selector,
1376 policy->family, dir);
1377
1378 if (!chain) {
1379 void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1380
1381 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1382 continue;
1383 }
1384
1385 hlist_for_each_entry(pol, chain, bydst) {
1386 if (policy->priority >= pol->priority)
1387 newpos = &pol->bydst;
1388 else
1389 break;
1390 }
1391 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1392 hlist_add_behind_rcu(&policy->bydst, newpos);
1393 else
1394 hlist_add_head_rcu(&policy->bydst, chain);
1395 }
1396
1397out_unlock:
1398 __xfrm_policy_inexact_flush(net);
1399 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1400 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1401
1402 mutex_unlock(&hash_resize_mutex);
1403}
1404
1405void xfrm_policy_hash_rebuild(struct net *net)
1406{
1407 schedule_work(&net->xfrm.policy_hthresh.work);
1408}
1409EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1410
1411/* Generate new index... KAME seems to generate them ordered by cost
1412 * of an absolute inpredictability of ordering of rules. This will not pass. */
1413static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1414{
1415 for (;;) {
1416 struct hlist_head *list;
1417 struct xfrm_policy *p;
1418 u32 idx;
1419 int found;
1420
1421 if (!index) {
1422 idx = (net->xfrm.idx_generator | dir);
1423 net->xfrm.idx_generator += 8;
1424 } else {
1425 idx = index;
1426 index = 0;
1427 }
1428
1429 if (idx == 0)
1430 idx = 8;
1431 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1432 found = 0;
1433 hlist_for_each_entry(p, list, byidx) {
1434 if (p->index == idx) {
1435 found = 1;
1436 break;
1437 }
1438 }
1439 if (!found)
1440 return idx;
1441 }
1442}
1443
1444static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1445{
1446 u32 *p1 = (u32 *) s1;
1447 u32 *p2 = (u32 *) s2;
1448 int len = sizeof(struct xfrm_selector) / sizeof(u32);
1449 int i;
1450
1451 for (i = 0; i < len; i++) {
1452 if (p1[i] != p2[i])
1453 return 1;
1454 }
1455
1456 return 0;
1457}
1458
1459static void xfrm_policy_requeue(struct xfrm_policy *old,
1460 struct xfrm_policy *new)
1461{
1462 struct xfrm_policy_queue *pq = &old->polq;
1463 struct sk_buff_head list;
1464
1465 if (skb_queue_empty(&pq->hold_queue))
1466 return;
1467
1468 __skb_queue_head_init(&list);
1469
1470 spin_lock_bh(&pq->hold_queue.lock);
1471 skb_queue_splice_init(&pq->hold_queue, &list);
1472 if (del_timer(&pq->hold_timer))
1473 xfrm_pol_put(old);
1474 spin_unlock_bh(&pq->hold_queue.lock);
1475
1476 pq = &new->polq;
1477
1478 spin_lock_bh(&pq->hold_queue.lock);
1479 skb_queue_splice(&list, &pq->hold_queue);
1480 pq->timeout = XFRM_QUEUE_TMO_MIN;
1481 if (!mod_timer(&pq->hold_timer, jiffies))
1482 xfrm_pol_hold(new);
1483 spin_unlock_bh(&pq->hold_queue.lock);
1484}
1485
1486static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1487 struct xfrm_policy *pol)
1488{
1489 return mark->v == pol->mark.v && mark->m == pol->mark.m;
1490}
1491
1492static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1493{
1494 const struct xfrm_pol_inexact_key *k = data;
1495 u32 a = k->type << 24 | k->dir << 16 | k->family;
1496
1497 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1498 seed);
1499}
1500
1501static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1502{
1503 const struct xfrm_pol_inexact_bin *b = data;
1504
1505 return xfrm_pol_bin_key(&b->k, 0, seed);
1506}
1507
1508static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1509 const void *ptr)
1510{
1511 const struct xfrm_pol_inexact_key *key = arg->key;
1512 const struct xfrm_pol_inexact_bin *b = ptr;
1513 int ret;
1514
1515 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1516 return -1;
1517
1518 ret = b->k.dir ^ key->dir;
1519 if (ret)
1520 return ret;
1521
1522 ret = b->k.type ^ key->type;
1523 if (ret)
1524 return ret;
1525
1526 ret = b->k.family ^ key->family;
1527 if (ret)
1528 return ret;
1529
1530 return b->k.if_id ^ key->if_id;
1531}
1532
1533static const struct rhashtable_params xfrm_pol_inexact_params = {
1534 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head),
1535 .hashfn = xfrm_pol_bin_key,
1536 .obj_hashfn = xfrm_pol_bin_obj,
1537 .obj_cmpfn = xfrm_pol_bin_cmp,
1538 .automatic_shrinking = true,
1539};
1540
1541static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1542 struct xfrm_policy *policy,
1543 bool excl)
1544{
1545 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1546
1547 hlist_for_each_entry(pol, chain, bydst) {
1548 if (pol->type == policy->type &&
1549 pol->if_id == policy->if_id &&
1550 !selector_cmp(&pol->selector, &policy->selector) &&
1551 xfrm_policy_mark_match(&policy->mark, pol) &&
1552 xfrm_sec_ctx_match(pol->security, policy->security) &&
1553 !WARN_ON(delpol)) {
1554 if (excl)
1555 return ERR_PTR(-EEXIST);
1556 delpol = pol;
1557 if (policy->priority > pol->priority)
1558 continue;
1559 } else if (policy->priority >= pol->priority) {
1560 newpos = pol;
1561 continue;
1562 }
1563 if (delpol)
1564 break;
1565 }
1566
1567 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1568 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1569 else
1570 /* Packet offload policies enter to the head
1571 * to speed-up lookups.
1572 */
1573 hlist_add_head_rcu(&policy->bydst, chain);
1574
1575 return delpol;
1576}
1577
1578int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1579{
1580 struct net *net = xp_net(policy);
1581 struct xfrm_policy *delpol;
1582 struct hlist_head *chain;
1583
1584 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1585 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1586 if (chain)
1587 delpol = xfrm_policy_insert_list(chain, policy, excl);
1588 else
1589 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1590
1591 if (IS_ERR(delpol)) {
1592 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1593 return PTR_ERR(delpol);
1594 }
1595
1596 __xfrm_policy_link(policy, dir);
1597
1598 /* After previous checking, family can either be AF_INET or AF_INET6 */
1599 if (policy->family == AF_INET)
1600 rt_genid_bump_ipv4(net);
1601 else
1602 rt_genid_bump_ipv6(net);
1603
1604 if (delpol) {
1605 xfrm_policy_requeue(delpol, policy);
1606 __xfrm_policy_unlink(delpol, dir);
1607 }
1608 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1609 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1610 policy->curlft.add_time = ktime_get_real_seconds();
1611 policy->curlft.use_time = 0;
1612 if (!mod_timer(&policy->timer, jiffies + HZ))
1613 xfrm_pol_hold(policy);
1614 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1615
1616 if (delpol)
1617 xfrm_policy_kill(delpol);
1618 else if (xfrm_bydst_should_resize(net, dir, NULL))
1619 schedule_work(&net->xfrm.policy_hash_work);
1620
1621 return 0;
1622}
1623EXPORT_SYMBOL(xfrm_policy_insert);
1624
1625static struct xfrm_policy *
1626__xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1627 u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1628 struct xfrm_sec_ctx *ctx)
1629{
1630 struct xfrm_policy *pol;
1631
1632 if (!chain)
1633 return NULL;
1634
1635 hlist_for_each_entry(pol, chain, bydst) {
1636 if (pol->type == type &&
1637 pol->if_id == if_id &&
1638 xfrm_policy_mark_match(mark, pol) &&
1639 !selector_cmp(sel, &pol->selector) &&
1640 xfrm_sec_ctx_match(ctx, pol->security))
1641 return pol;
1642 }
1643
1644 return NULL;
1645}
1646
1647struct xfrm_policy *
1648xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1649 u8 type, int dir, struct xfrm_selector *sel,
1650 struct xfrm_sec_ctx *ctx, int delete, int *err)
1651{
1652 struct xfrm_pol_inexact_bin *bin = NULL;
1653 struct xfrm_policy *pol, *ret = NULL;
1654 struct hlist_head *chain;
1655
1656 *err = 0;
1657 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1658 chain = policy_hash_bysel(net, sel, sel->family, dir);
1659 if (!chain) {
1660 struct xfrm_pol_inexact_candidates cand;
1661 int i;
1662
1663 bin = xfrm_policy_inexact_lookup(net, type,
1664 sel->family, dir, if_id);
1665 if (!bin) {
1666 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1667 return NULL;
1668 }
1669
1670 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1671 &sel->saddr,
1672 &sel->daddr)) {
1673 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1674 return NULL;
1675 }
1676
1677 pol = NULL;
1678 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1679 struct xfrm_policy *tmp;
1680
1681 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1682 if_id, type, dir,
1683 sel, ctx);
1684 if (!tmp)
1685 continue;
1686
1687 if (!pol || tmp->pos < pol->pos)
1688 pol = tmp;
1689 }
1690 } else {
1691 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1692 sel, ctx);
1693 }
1694
1695 if (pol) {
1696 xfrm_pol_hold(pol);
1697 if (delete) {
1698 *err = security_xfrm_policy_delete(pol->security);
1699 if (*err) {
1700 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1701 return pol;
1702 }
1703 __xfrm_policy_unlink(pol, dir);
1704 }
1705 ret = pol;
1706 }
1707 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1708
1709 if (ret && delete)
1710 xfrm_policy_kill(ret);
1711 if (bin && delete)
1712 xfrm_policy_inexact_prune_bin(bin);
1713 return ret;
1714}
1715EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1716
1717struct xfrm_policy *
1718xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1719 u8 type, int dir, u32 id, int delete, int *err)
1720{
1721 struct xfrm_policy *pol, *ret;
1722 struct hlist_head *chain;
1723
1724 *err = -ENOENT;
1725 if (xfrm_policy_id2dir(id) != dir)
1726 return NULL;
1727
1728 *err = 0;
1729 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1730 chain = net->xfrm.policy_byidx + idx_hash(net, id);
1731 ret = NULL;
1732 hlist_for_each_entry(pol, chain, byidx) {
1733 if (pol->type == type && pol->index == id &&
1734 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1735 xfrm_pol_hold(pol);
1736 if (delete) {
1737 *err = security_xfrm_policy_delete(
1738 pol->security);
1739 if (*err) {
1740 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1741 return pol;
1742 }
1743 __xfrm_policy_unlink(pol, dir);
1744 }
1745 ret = pol;
1746 break;
1747 }
1748 }
1749 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1750
1751 if (ret && delete)
1752 xfrm_policy_kill(ret);
1753 return ret;
1754}
1755EXPORT_SYMBOL(xfrm_policy_byid);
1756
1757#ifdef CONFIG_SECURITY_NETWORK_XFRM
1758static inline int
1759xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1760{
1761 struct xfrm_policy *pol;
1762 int err = 0;
1763
1764 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1765 if (pol->walk.dead ||
1766 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1767 pol->type != type)
1768 continue;
1769
1770 err = security_xfrm_policy_delete(pol->security);
1771 if (err) {
1772 xfrm_audit_policy_delete(pol, 0, task_valid);
1773 return err;
1774 }
1775 }
1776 return err;
1777}
1778
1779static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1780 struct net_device *dev,
1781 bool task_valid)
1782{
1783 struct xfrm_policy *pol;
1784 int err = 0;
1785
1786 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1787 if (pol->walk.dead ||
1788 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1789 pol->xdo.dev != dev)
1790 continue;
1791
1792 err = security_xfrm_policy_delete(pol->security);
1793 if (err) {
1794 xfrm_audit_policy_delete(pol, 0, task_valid);
1795 return err;
1796 }
1797 }
1798 return err;
1799}
1800#else
1801static inline int
1802xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1803{
1804 return 0;
1805}
1806
1807static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1808 struct net_device *dev,
1809 bool task_valid)
1810{
1811 return 0;
1812}
1813#endif
1814
1815int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1816{
1817 int dir, err = 0, cnt = 0;
1818 struct xfrm_policy *pol;
1819
1820 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1821
1822 err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1823 if (err)
1824 goto out;
1825
1826again:
1827 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1828 if (pol->walk.dead)
1829 continue;
1830
1831 dir = xfrm_policy_id2dir(pol->index);
1832 if (dir >= XFRM_POLICY_MAX ||
1833 pol->type != type)
1834 continue;
1835
1836 __xfrm_policy_unlink(pol, dir);
1837 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1838 cnt++;
1839 xfrm_audit_policy_delete(pol, 1, task_valid);
1840 xfrm_policy_kill(pol);
1841 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1842 goto again;
1843 }
1844 if (cnt)
1845 __xfrm_policy_inexact_flush(net);
1846 else
1847 err = -ESRCH;
1848out:
1849 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1850 return err;
1851}
1852EXPORT_SYMBOL(xfrm_policy_flush);
1853
1854int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
1855 bool task_valid)
1856{
1857 int dir, err = 0, cnt = 0;
1858 struct xfrm_policy *pol;
1859
1860 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1861
1862 err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
1863 if (err)
1864 goto out;
1865
1866again:
1867 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1868 if (pol->walk.dead)
1869 continue;
1870
1871 dir = xfrm_policy_id2dir(pol->index);
1872 if (dir >= XFRM_POLICY_MAX ||
1873 pol->xdo.dev != dev)
1874 continue;
1875
1876 __xfrm_policy_unlink(pol, dir);
1877 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1878 cnt++;
1879 xfrm_audit_policy_delete(pol, 1, task_valid);
1880 xfrm_policy_kill(pol);
1881 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1882 goto again;
1883 }
1884 if (cnt)
1885 __xfrm_policy_inexact_flush(net);
1886 else
1887 err = -ESRCH;
1888out:
1889 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1890 return err;
1891}
1892EXPORT_SYMBOL(xfrm_dev_policy_flush);
1893
1894int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1895 int (*func)(struct xfrm_policy *, int, int, void*),
1896 void *data)
1897{
1898 struct xfrm_policy *pol;
1899 struct xfrm_policy_walk_entry *x;
1900 int error = 0;
1901
1902 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1903 walk->type != XFRM_POLICY_TYPE_ANY)
1904 return -EINVAL;
1905
1906 if (list_empty(&walk->walk.all) && walk->seq != 0)
1907 return 0;
1908
1909 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1910 if (list_empty(&walk->walk.all))
1911 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1912 else
1913 x = list_first_entry(&walk->walk.all,
1914 struct xfrm_policy_walk_entry, all);
1915
1916 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1917 if (x->dead)
1918 continue;
1919 pol = container_of(x, struct xfrm_policy, walk);
1920 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1921 walk->type != pol->type)
1922 continue;
1923 error = func(pol, xfrm_policy_id2dir(pol->index),
1924 walk->seq, data);
1925 if (error) {
1926 list_move_tail(&walk->walk.all, &x->all);
1927 goto out;
1928 }
1929 walk->seq++;
1930 }
1931 if (walk->seq == 0) {
1932 error = -ENOENT;
1933 goto out;
1934 }
1935 list_del_init(&walk->walk.all);
1936out:
1937 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1938 return error;
1939}
1940EXPORT_SYMBOL(xfrm_policy_walk);
1941
1942void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1943{
1944 INIT_LIST_HEAD(&walk->walk.all);
1945 walk->walk.dead = 1;
1946 walk->type = type;
1947 walk->seq = 0;
1948}
1949EXPORT_SYMBOL(xfrm_policy_walk_init);
1950
1951void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1952{
1953 if (list_empty(&walk->walk.all))
1954 return;
1955
1956 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1957 list_del(&walk->walk.all);
1958 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1959}
1960EXPORT_SYMBOL(xfrm_policy_walk_done);
1961
1962/*
1963 * Find policy to apply to this flow.
1964 *
1965 * Returns 0 if policy found, else an -errno.
1966 */
1967static int xfrm_policy_match(const struct xfrm_policy *pol,
1968 const struct flowi *fl,
1969 u8 type, u16 family, u32 if_id)
1970{
1971 const struct xfrm_selector *sel = &pol->selector;
1972 int ret = -ESRCH;
1973 bool match;
1974
1975 if (pol->family != family ||
1976 pol->if_id != if_id ||
1977 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1978 pol->type != type)
1979 return ret;
1980
1981 match = xfrm_selector_match(sel, fl, family);
1982 if (match)
1983 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
1984 return ret;
1985}
1986
1987static struct xfrm_pol_inexact_node *
1988xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1989 seqcount_spinlock_t *count,
1990 const xfrm_address_t *addr, u16 family)
1991{
1992 const struct rb_node *parent;
1993 int seq;
1994
1995again:
1996 seq = read_seqcount_begin(count);
1997
1998 parent = rcu_dereference_raw(r->rb_node);
1999 while (parent) {
2000 struct xfrm_pol_inexact_node *node;
2001 int delta;
2002
2003 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
2004
2005 delta = xfrm_policy_addr_delta(addr, &node->addr,
2006 node->prefixlen, family);
2007 if (delta < 0) {
2008 parent = rcu_dereference_raw(parent->rb_left);
2009 continue;
2010 } else if (delta > 0) {
2011 parent = rcu_dereference_raw(parent->rb_right);
2012 continue;
2013 }
2014
2015 return node;
2016 }
2017
2018 if (read_seqcount_retry(count, seq))
2019 goto again;
2020
2021 return NULL;
2022}
2023
2024static bool
2025xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
2026 struct xfrm_pol_inexact_bin *b,
2027 const xfrm_address_t *saddr,
2028 const xfrm_address_t *daddr)
2029{
2030 struct xfrm_pol_inexact_node *n;
2031 u16 family;
2032
2033 if (!b)
2034 return false;
2035
2036 family = b->k.family;
2037 memset(cand, 0, sizeof(*cand));
2038 cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
2039
2040 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
2041 family);
2042 if (n) {
2043 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
2044 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
2045 family);
2046 if (n)
2047 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
2048 }
2049
2050 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
2051 family);
2052 if (n)
2053 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
2054
2055 return true;
2056}
2057
2058static struct xfrm_pol_inexact_bin *
2059xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
2060 u8 dir, u32 if_id)
2061{
2062 struct xfrm_pol_inexact_key k = {
2063 .family = family,
2064 .type = type,
2065 .dir = dir,
2066 .if_id = if_id,
2067 };
2068
2069 write_pnet(&k.net, net);
2070
2071 return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
2072 xfrm_pol_inexact_params);
2073}
2074
2075static struct xfrm_pol_inexact_bin *
2076xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2077 u8 dir, u32 if_id)
2078{
2079 struct xfrm_pol_inexact_bin *bin;
2080
2081 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2082
2083 rcu_read_lock();
2084 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2085 rcu_read_unlock();
2086
2087 return bin;
2088}
2089
2090static struct xfrm_policy *
2091__xfrm_policy_eval_candidates(struct hlist_head *chain,
2092 struct xfrm_policy *prefer,
2093 const struct flowi *fl,
2094 u8 type, u16 family, u32 if_id)
2095{
2096 u32 priority = prefer ? prefer->priority : ~0u;
2097 struct xfrm_policy *pol;
2098
2099 if (!chain)
2100 return NULL;
2101
2102 hlist_for_each_entry_rcu(pol, chain, bydst) {
2103 int err;
2104
2105 if (pol->priority > priority)
2106 break;
2107
2108 err = xfrm_policy_match(pol, fl, type, family, if_id);
2109 if (err) {
2110 if (err != -ESRCH)
2111 return ERR_PTR(err);
2112
2113 continue;
2114 }
2115
2116 if (prefer) {
2117 /* matches. Is it older than *prefer? */
2118 if (pol->priority == priority &&
2119 prefer->pos < pol->pos)
2120 return prefer;
2121 }
2122
2123 return pol;
2124 }
2125
2126 return NULL;
2127}
2128
2129static struct xfrm_policy *
2130xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2131 struct xfrm_policy *prefer,
2132 const struct flowi *fl,
2133 u8 type, u16 family, u32 if_id)
2134{
2135 struct xfrm_policy *tmp;
2136 int i;
2137
2138 for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2139 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2140 prefer,
2141 fl, type, family, if_id);
2142 if (!tmp)
2143 continue;
2144
2145 if (IS_ERR(tmp))
2146 return tmp;
2147 prefer = tmp;
2148 }
2149
2150 return prefer;
2151}
2152
2153static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2154 const struct flowi *fl,
2155 u16 family, u8 dir,
2156 u32 if_id)
2157{
2158 struct xfrm_pol_inexact_candidates cand;
2159 const xfrm_address_t *daddr, *saddr;
2160 struct xfrm_pol_inexact_bin *bin;
2161 struct xfrm_policy *pol, *ret;
2162 struct hlist_head *chain;
2163 unsigned int sequence;
2164 int err;
2165
2166 daddr = xfrm_flowi_daddr(fl, family);
2167 saddr = xfrm_flowi_saddr(fl, family);
2168 if (unlikely(!daddr || !saddr))
2169 return NULL;
2170
2171 rcu_read_lock();
2172 retry:
2173 do {
2174 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2175 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2176 } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2177
2178 ret = NULL;
2179 hlist_for_each_entry_rcu(pol, chain, bydst) {
2180 err = xfrm_policy_match(pol, fl, type, family, if_id);
2181 if (err) {
2182 if (err == -ESRCH)
2183 continue;
2184 else {
2185 ret = ERR_PTR(err);
2186 goto fail;
2187 }
2188 } else {
2189 ret = pol;
2190 break;
2191 }
2192 }
2193 if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
2194 goto skip_inexact;
2195
2196 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2197 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2198 daddr))
2199 goto skip_inexact;
2200
2201 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2202 family, if_id);
2203 if (pol) {
2204 ret = pol;
2205 if (IS_ERR(pol))
2206 goto fail;
2207 }
2208
2209skip_inexact:
2210 if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2211 goto retry;
2212
2213 if (ret && !xfrm_pol_hold_rcu(ret))
2214 goto retry;
2215fail:
2216 rcu_read_unlock();
2217
2218 return ret;
2219}
2220
2221static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2222 const struct flowi *fl,
2223 u16 family, u8 dir, u32 if_id)
2224{
2225#ifdef CONFIG_XFRM_SUB_POLICY
2226 struct xfrm_policy *pol;
2227
2228 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2229 dir, if_id);
2230 if (pol != NULL)
2231 return pol;
2232#endif
2233 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2234 dir, if_id);
2235}
2236
2237static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2238 const struct flowi *fl,
2239 u16 family, u32 if_id)
2240{
2241 struct xfrm_policy *pol;
2242
2243 rcu_read_lock();
2244 again:
2245 pol = rcu_dereference(sk->sk_policy[dir]);
2246 if (pol != NULL) {
2247 bool match;
2248 int err = 0;
2249
2250 if (pol->family != family) {
2251 pol = NULL;
2252 goto out;
2253 }
2254
2255 match = xfrm_selector_match(&pol->selector, fl, family);
2256 if (match) {
2257 if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v ||
2258 pol->if_id != if_id) {
2259 pol = NULL;
2260 goto out;
2261 }
2262 err = security_xfrm_policy_lookup(pol->security,
2263 fl->flowi_secid);
2264 if (!err) {
2265 if (!xfrm_pol_hold_rcu(pol))
2266 goto again;
2267 } else if (err == -ESRCH) {
2268 pol = NULL;
2269 } else {
2270 pol = ERR_PTR(err);
2271 }
2272 } else
2273 pol = NULL;
2274 }
2275out:
2276 rcu_read_unlock();
2277 return pol;
2278}
2279
2280static u32 xfrm_gen_pos_slow(struct net *net)
2281{
2282 struct xfrm_policy *policy;
2283 u32 i = 0;
2284
2285 /* oldest entry is last in list */
2286 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
2287 if (!xfrm_policy_is_dead_or_sk(policy))
2288 policy->pos = ++i;
2289 }
2290
2291 return i;
2292}
2293
2294static u32 xfrm_gen_pos(struct net *net)
2295{
2296 const struct xfrm_policy *policy;
2297 u32 i = 0;
2298
2299 /* most recently added policy is at the head of the list */
2300 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
2301 if (xfrm_policy_is_dead_or_sk(policy))
2302 continue;
2303
2304 if (policy->pos == UINT_MAX)
2305 return xfrm_gen_pos_slow(net);
2306
2307 i = policy->pos + 1;
2308 break;
2309 }
2310
2311 return i;
2312}
2313
2314static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2315{
2316 struct net *net = xp_net(pol);
2317
2318 switch (dir) {
2319 case XFRM_POLICY_IN:
2320 case XFRM_POLICY_FWD:
2321 case XFRM_POLICY_OUT:
2322 pol->pos = xfrm_gen_pos(net);
2323 break;
2324 }
2325
2326 list_add(&pol->walk.all, &net->xfrm.policy_all);
2327 net->xfrm.policy_count[dir]++;
2328 xfrm_pol_hold(pol);
2329}
2330
2331static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2332 int dir)
2333{
2334 struct net *net = xp_net(pol);
2335
2336 if (list_empty(&pol->walk.all))
2337 return NULL;
2338
2339 /* Socket policies are not hashed. */
2340 if (!hlist_unhashed(&pol->bydst)) {
2341 hlist_del_rcu(&pol->bydst);
2342 hlist_del(&pol->byidx);
2343 }
2344
2345 list_del_init(&pol->walk.all);
2346 net->xfrm.policy_count[dir]--;
2347
2348 return pol;
2349}
2350
2351static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2352{
2353 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2354}
2355
2356static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2357{
2358 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2359}
2360
2361int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2362{
2363 struct net *net = xp_net(pol);
2364
2365 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2366 pol = __xfrm_policy_unlink(pol, dir);
2367 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2368 if (pol) {
2369 xfrm_policy_kill(pol);
2370 return 0;
2371 }
2372 return -ENOENT;
2373}
2374EXPORT_SYMBOL(xfrm_policy_delete);
2375
2376int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2377{
2378 struct net *net = sock_net(sk);
2379 struct xfrm_policy *old_pol;
2380
2381#ifdef CONFIG_XFRM_SUB_POLICY
2382 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2383 return -EINVAL;
2384#endif
2385
2386 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2387 old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2388 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2389 if (pol) {
2390 pol->curlft.add_time = ktime_get_real_seconds();
2391 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2392 xfrm_sk_policy_link(pol, dir);
2393 }
2394 rcu_assign_pointer(sk->sk_policy[dir], pol);
2395 if (old_pol) {
2396 if (pol)
2397 xfrm_policy_requeue(old_pol, pol);
2398
2399 /* Unlinking succeeds always. This is the only function
2400 * allowed to delete or replace socket policy.
2401 */
2402 xfrm_sk_policy_unlink(old_pol, dir);
2403 }
2404 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2405
2406 if (old_pol) {
2407 xfrm_policy_kill(old_pol);
2408 }
2409 return 0;
2410}
2411
2412static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2413{
2414 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2415 struct net *net = xp_net(old);
2416
2417 if (newp) {
2418 newp->selector = old->selector;
2419 if (security_xfrm_policy_clone(old->security,
2420 &newp->security)) {
2421 kfree(newp);
2422 return NULL; /* ENOMEM */
2423 }
2424 newp->lft = old->lft;
2425 newp->curlft = old->curlft;
2426 newp->mark = old->mark;
2427 newp->if_id = old->if_id;
2428 newp->action = old->action;
2429 newp->flags = old->flags;
2430 newp->xfrm_nr = old->xfrm_nr;
2431 newp->index = old->index;
2432 newp->type = old->type;
2433 newp->family = old->family;
2434 memcpy(newp->xfrm_vec, old->xfrm_vec,
2435 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2436 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2437 xfrm_sk_policy_link(newp, dir);
2438 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2439 xfrm_pol_put(newp);
2440 }
2441 return newp;
2442}
2443
2444int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2445{
2446 const struct xfrm_policy *p;
2447 struct xfrm_policy *np;
2448 int i, ret = 0;
2449
2450 rcu_read_lock();
2451 for (i = 0; i < 2; i++) {
2452 p = rcu_dereference(osk->sk_policy[i]);
2453 if (p) {
2454 np = clone_policy(p, i);
2455 if (unlikely(!np)) {
2456 ret = -ENOMEM;
2457 break;
2458 }
2459 rcu_assign_pointer(sk->sk_policy[i], np);
2460 }
2461 }
2462 rcu_read_unlock();
2463 return ret;
2464}
2465
2466static int
2467xfrm_get_saddr(unsigned short family, xfrm_address_t *saddr,
2468 const struct xfrm_dst_lookup_params *params)
2469{
2470 int err;
2471 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2472
2473 if (unlikely(afinfo == NULL))
2474 return -EINVAL;
2475 err = afinfo->get_saddr(saddr, params);
2476 rcu_read_unlock();
2477 return err;
2478}
2479
2480/* Resolve list of templates for the flow, given policy. */
2481
2482static int
2483xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2484 struct xfrm_state **xfrm, unsigned short family)
2485{
2486 struct net *net = xp_net(policy);
2487 int nx;
2488 int i, error;
2489 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2490 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2491 xfrm_address_t tmp;
2492
2493 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2494 struct xfrm_state *x;
2495 xfrm_address_t *remote = daddr;
2496 xfrm_address_t *local = saddr;
2497 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2498
2499 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2500 tmpl->mode == XFRM_MODE_BEET) {
2501 remote = &tmpl->id.daddr;
2502 local = &tmpl->saddr;
2503 if (xfrm_addr_any(local, tmpl->encap_family)) {
2504 struct xfrm_dst_lookup_params params;
2505
2506 memset(¶ms, 0, sizeof(params));
2507 params.net = net;
2508 params.oif = fl->flowi_oif;
2509 params.daddr = remote;
2510 error = xfrm_get_saddr(tmpl->encap_family, &tmp,
2511 ¶ms);
2512 if (error)
2513 goto fail;
2514 local = &tmp;
2515 }
2516 }
2517
2518 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2519 family, policy->if_id);
2520 if (x && x->dir && x->dir != XFRM_SA_DIR_OUT) {
2521 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEDIRERROR);
2522 xfrm_state_put(x);
2523 error = -EINVAL;
2524 goto fail;
2525 }
2526
2527 if (x && x->km.state == XFRM_STATE_VALID) {
2528 xfrm[nx++] = x;
2529 daddr = remote;
2530 saddr = local;
2531 continue;
2532 }
2533 if (x) {
2534 error = (x->km.state == XFRM_STATE_ERROR ?
2535 -EINVAL : -EAGAIN);
2536 xfrm_state_put(x);
2537 } else if (error == -ESRCH) {
2538 error = -EAGAIN;
2539 }
2540
2541 if (!tmpl->optional)
2542 goto fail;
2543 }
2544 return nx;
2545
2546fail:
2547 for (nx--; nx >= 0; nx--)
2548 xfrm_state_put(xfrm[nx]);
2549 return error;
2550}
2551
2552static int
2553xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2554 struct xfrm_state **xfrm, unsigned short family)
2555{
2556 struct xfrm_state *tp[XFRM_MAX_DEPTH];
2557 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2558 int cnx = 0;
2559 int error;
2560 int ret;
2561 int i;
2562
2563 for (i = 0; i < npols; i++) {
2564 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2565 error = -ENOBUFS;
2566 goto fail;
2567 }
2568
2569 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2570 if (ret < 0) {
2571 error = ret;
2572 goto fail;
2573 } else
2574 cnx += ret;
2575 }
2576
2577 /* found states are sorted for outbound processing */
2578 if (npols > 1)
2579 xfrm_state_sort(xfrm, tpp, cnx, family);
2580
2581 return cnx;
2582
2583 fail:
2584 for (cnx--; cnx >= 0; cnx--)
2585 xfrm_state_put(tpp[cnx]);
2586 return error;
2587
2588}
2589
2590static dscp_t xfrm_get_dscp(const struct flowi *fl, int family)
2591{
2592 if (family == AF_INET)
2593 return inet_dsfield_to_dscp(fl->u.ip4.flowi4_tos);
2594
2595 return 0;
2596}
2597
2598static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2599{
2600 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2601 struct dst_ops *dst_ops;
2602 struct xfrm_dst *xdst;
2603
2604 if (!afinfo)
2605 return ERR_PTR(-EINVAL);
2606
2607 switch (family) {
2608 case AF_INET:
2609 dst_ops = &net->xfrm.xfrm4_dst_ops;
2610 break;
2611#if IS_ENABLED(CONFIG_IPV6)
2612 case AF_INET6:
2613 dst_ops = &net->xfrm.xfrm6_dst_ops;
2614 break;
2615#endif
2616 default:
2617 BUG();
2618 }
2619 xdst = dst_alloc(dst_ops, NULL, DST_OBSOLETE_NONE, 0);
2620
2621 if (likely(xdst)) {
2622 memset_after(xdst, 0, u.dst);
2623 } else
2624 xdst = ERR_PTR(-ENOBUFS);
2625
2626 rcu_read_unlock();
2627
2628 return xdst;
2629}
2630
2631static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2632 int nfheader_len)
2633{
2634 if (dst->ops->family == AF_INET6) {
2635 path->path_cookie = rt6_get_cookie(dst_rt6_info(dst));
2636 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2637 }
2638}
2639
2640static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2641 const struct flowi *fl)
2642{
2643 const struct xfrm_policy_afinfo *afinfo =
2644 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2645 int err;
2646
2647 if (!afinfo)
2648 return -EINVAL;
2649
2650 err = afinfo->fill_dst(xdst, dev, fl);
2651
2652 rcu_read_unlock();
2653
2654 return err;
2655}
2656
2657
2658/* Allocate chain of dst_entry's, attach known xfrm's, calculate
2659 * all the metrics... Shortly, bundle a bundle.
2660 */
2661
2662static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2663 struct xfrm_state **xfrm,
2664 struct xfrm_dst **bundle,
2665 int nx,
2666 const struct flowi *fl,
2667 struct dst_entry *dst)
2668{
2669 const struct xfrm_state_afinfo *afinfo;
2670 const struct xfrm_mode *inner_mode;
2671 struct net *net = xp_net(policy);
2672 unsigned long now = jiffies;
2673 struct net_device *dev;
2674 struct xfrm_dst *xdst_prev = NULL;
2675 struct xfrm_dst *xdst0 = NULL;
2676 int i = 0;
2677 int err;
2678 int header_len = 0;
2679 int nfheader_len = 0;
2680 int trailer_len = 0;
2681 int family = policy->selector.family;
2682 xfrm_address_t saddr, daddr;
2683 dscp_t dscp;
2684
2685 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2686
2687 dscp = xfrm_get_dscp(fl, family);
2688
2689 dst_hold(dst);
2690
2691 for (; i < nx; i++) {
2692 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2693 struct dst_entry *dst1 = &xdst->u.dst;
2694
2695 err = PTR_ERR(xdst);
2696 if (IS_ERR(xdst)) {
2697 dst_release(dst);
2698 goto put_states;
2699 }
2700
2701 bundle[i] = xdst;
2702 if (!xdst_prev)
2703 xdst0 = xdst;
2704 else
2705 /* Ref count is taken during xfrm_alloc_dst()
2706 * No need to do dst_clone() on dst1
2707 */
2708 xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2709
2710 if (xfrm[i]->sel.family == AF_UNSPEC) {
2711 inner_mode = xfrm_ip2inner_mode(xfrm[i],
2712 xfrm_af2proto(family));
2713 if (!inner_mode) {
2714 err = -EAFNOSUPPORT;
2715 dst_release(dst);
2716 goto put_states;
2717 }
2718 } else
2719 inner_mode = &xfrm[i]->inner_mode;
2720
2721 xdst->route = dst;
2722 dst_copy_metrics(dst1, dst);
2723
2724 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2725 __u32 mark = 0;
2726 int oif;
2727
2728 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2729 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2730
2731 if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET)
2732 family = xfrm[i]->props.family;
2733
2734 oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2735 dst = xfrm_dst_lookup(xfrm[i], dscp, oif, &saddr,
2736 &daddr, family, mark);
2737 err = PTR_ERR(dst);
2738 if (IS_ERR(dst))
2739 goto put_states;
2740 } else
2741 dst_hold(dst);
2742
2743 dst1->xfrm = xfrm[i];
2744 xdst->xfrm_genid = xfrm[i]->genid;
2745
2746 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2747 dst1->lastuse = now;
2748
2749 dst1->input = dst_discard;
2750
2751 rcu_read_lock();
2752 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2753 if (likely(afinfo))
2754 dst1->output = afinfo->output;
2755 else
2756 dst1->output = dst_discard_out;
2757 rcu_read_unlock();
2758
2759 xdst_prev = xdst;
2760
2761 header_len += xfrm[i]->props.header_len;
2762 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2763 nfheader_len += xfrm[i]->props.header_len;
2764 trailer_len += xfrm[i]->props.trailer_len;
2765 }
2766
2767 xfrm_dst_set_child(xdst_prev, dst);
2768 xdst0->path = dst;
2769
2770 err = -ENODEV;
2771 dev = dst->dev;
2772 if (!dev)
2773 goto free_dst;
2774
2775 xfrm_init_path(xdst0, dst, nfheader_len);
2776 xfrm_init_pmtu(bundle, nx);
2777
2778 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2779 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2780 err = xfrm_fill_dst(xdst_prev, dev, fl);
2781 if (err)
2782 goto free_dst;
2783
2784 xdst_prev->u.dst.header_len = header_len;
2785 xdst_prev->u.dst.trailer_len = trailer_len;
2786 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2787 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2788 }
2789
2790 return &xdst0->u.dst;
2791
2792put_states:
2793 for (; i < nx; i++)
2794 xfrm_state_put(xfrm[i]);
2795free_dst:
2796 if (xdst0)
2797 dst_release_immediate(&xdst0->u.dst);
2798
2799 return ERR_PTR(err);
2800}
2801
2802static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2803 struct xfrm_policy **pols,
2804 int *num_pols, int *num_xfrms)
2805{
2806 int i;
2807
2808 if (*num_pols == 0 || !pols[0]) {
2809 *num_pols = 0;
2810 *num_xfrms = 0;
2811 return 0;
2812 }
2813 if (IS_ERR(pols[0])) {
2814 *num_pols = 0;
2815 return PTR_ERR(pols[0]);
2816 }
2817
2818 *num_xfrms = pols[0]->xfrm_nr;
2819
2820#ifdef CONFIG_XFRM_SUB_POLICY
2821 if (pols[0]->action == XFRM_POLICY_ALLOW &&
2822 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2823 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2824 XFRM_POLICY_TYPE_MAIN,
2825 fl, family,
2826 XFRM_POLICY_OUT,
2827 pols[0]->if_id);
2828 if (pols[1]) {
2829 if (IS_ERR(pols[1])) {
2830 xfrm_pols_put(pols, *num_pols);
2831 *num_pols = 0;
2832 return PTR_ERR(pols[1]);
2833 }
2834 (*num_pols)++;
2835 (*num_xfrms) += pols[1]->xfrm_nr;
2836 }
2837 }
2838#endif
2839 for (i = 0; i < *num_pols; i++) {
2840 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2841 *num_xfrms = -1;
2842 break;
2843 }
2844 }
2845
2846 return 0;
2847
2848}
2849
2850static struct xfrm_dst *
2851xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2852 const struct flowi *fl, u16 family,
2853 struct dst_entry *dst_orig)
2854{
2855 struct net *net = xp_net(pols[0]);
2856 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2857 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2858 struct xfrm_dst *xdst;
2859 struct dst_entry *dst;
2860 int err;
2861
2862 /* Try to instantiate a bundle */
2863 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2864 if (err <= 0) {
2865 if (err == 0)
2866 return NULL;
2867
2868 if (err != -EAGAIN)
2869 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2870 return ERR_PTR(err);
2871 }
2872
2873 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2874 if (IS_ERR(dst)) {
2875 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2876 return ERR_CAST(dst);
2877 }
2878
2879 xdst = (struct xfrm_dst *)dst;
2880 xdst->num_xfrms = err;
2881 xdst->num_pols = num_pols;
2882 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2883 xdst->policy_genid = atomic_read(&pols[0]->genid);
2884
2885 return xdst;
2886}
2887
2888static void xfrm_policy_queue_process(struct timer_list *t)
2889{
2890 struct sk_buff *skb;
2891 struct sock *sk;
2892 struct dst_entry *dst;
2893 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2894 struct net *net = xp_net(pol);
2895 struct xfrm_policy_queue *pq = &pol->polq;
2896 struct flowi fl;
2897 struct sk_buff_head list;
2898 __u32 skb_mark;
2899
2900 spin_lock(&pq->hold_queue.lock);
2901 skb = skb_peek(&pq->hold_queue);
2902 if (!skb) {
2903 spin_unlock(&pq->hold_queue.lock);
2904 goto out;
2905 }
2906 dst = skb_dst(skb);
2907 sk = skb->sk;
2908
2909 /* Fixup the mark to support VTI. */
2910 skb_mark = skb->mark;
2911 skb->mark = pol->mark.v;
2912 xfrm_decode_session(net, skb, &fl, dst->ops->family);
2913 skb->mark = skb_mark;
2914 spin_unlock(&pq->hold_queue.lock);
2915
2916 dst_hold(xfrm_dst_path(dst));
2917 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2918 if (IS_ERR(dst))
2919 goto purge_queue;
2920
2921 if (dst->flags & DST_XFRM_QUEUE) {
2922 dst_release(dst);
2923
2924 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2925 goto purge_queue;
2926
2927 pq->timeout = pq->timeout << 1;
2928 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2929 xfrm_pol_hold(pol);
2930 goto out;
2931 }
2932
2933 dst_release(dst);
2934
2935 __skb_queue_head_init(&list);
2936
2937 spin_lock(&pq->hold_queue.lock);
2938 pq->timeout = 0;
2939 skb_queue_splice_init(&pq->hold_queue, &list);
2940 spin_unlock(&pq->hold_queue.lock);
2941
2942 while (!skb_queue_empty(&list)) {
2943 skb = __skb_dequeue(&list);
2944
2945 /* Fixup the mark to support VTI. */
2946 skb_mark = skb->mark;
2947 skb->mark = pol->mark.v;
2948 xfrm_decode_session(net, skb, &fl, skb_dst(skb)->ops->family);
2949 skb->mark = skb_mark;
2950
2951 dst_hold(xfrm_dst_path(skb_dst(skb)));
2952 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2953 if (IS_ERR(dst)) {
2954 kfree_skb(skb);
2955 continue;
2956 }
2957
2958 nf_reset_ct(skb);
2959 skb_dst_drop(skb);
2960 skb_dst_set(skb, dst);
2961
2962 dst_output(net, skb->sk, skb);
2963 }
2964
2965out:
2966 xfrm_pol_put(pol);
2967 return;
2968
2969purge_queue:
2970 pq->timeout = 0;
2971 skb_queue_purge(&pq->hold_queue);
2972 xfrm_pol_put(pol);
2973}
2974
2975static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2976{
2977 unsigned long sched_next;
2978 struct dst_entry *dst = skb_dst(skb);
2979 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2980 struct xfrm_policy *pol = xdst->pols[0];
2981 struct xfrm_policy_queue *pq = &pol->polq;
2982
2983 if (unlikely(skb_fclone_busy(sk, skb))) {
2984 kfree_skb(skb);
2985 return 0;
2986 }
2987
2988 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2989 kfree_skb(skb);
2990 return -EAGAIN;
2991 }
2992
2993 skb_dst_force(skb);
2994
2995 spin_lock_bh(&pq->hold_queue.lock);
2996
2997 if (!pq->timeout)
2998 pq->timeout = XFRM_QUEUE_TMO_MIN;
2999
3000 sched_next = jiffies + pq->timeout;
3001
3002 if (del_timer(&pq->hold_timer)) {
3003 if (time_before(pq->hold_timer.expires, sched_next))
3004 sched_next = pq->hold_timer.expires;
3005 xfrm_pol_put(pol);
3006 }
3007
3008 __skb_queue_tail(&pq->hold_queue, skb);
3009 if (!mod_timer(&pq->hold_timer, sched_next))
3010 xfrm_pol_hold(pol);
3011
3012 spin_unlock_bh(&pq->hold_queue.lock);
3013
3014 return 0;
3015}
3016
3017static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
3018 struct xfrm_flo *xflo,
3019 const struct flowi *fl,
3020 int num_xfrms,
3021 u16 family)
3022{
3023 int err;
3024 struct net_device *dev;
3025 struct dst_entry *dst;
3026 struct dst_entry *dst1;
3027 struct xfrm_dst *xdst;
3028
3029 xdst = xfrm_alloc_dst(net, family);
3030 if (IS_ERR(xdst))
3031 return xdst;
3032
3033 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
3034 net->xfrm.sysctl_larval_drop ||
3035 num_xfrms <= 0)
3036 return xdst;
3037
3038 dst = xflo->dst_orig;
3039 dst1 = &xdst->u.dst;
3040 dst_hold(dst);
3041 xdst->route = dst;
3042
3043 dst_copy_metrics(dst1, dst);
3044
3045 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
3046 dst1->flags |= DST_XFRM_QUEUE;
3047 dst1->lastuse = jiffies;
3048
3049 dst1->input = dst_discard;
3050 dst1->output = xdst_queue_output;
3051
3052 dst_hold(dst);
3053 xfrm_dst_set_child(xdst, dst);
3054 xdst->path = dst;
3055
3056 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
3057
3058 err = -ENODEV;
3059 dev = dst->dev;
3060 if (!dev)
3061 goto free_dst;
3062
3063 err = xfrm_fill_dst(xdst, dev, fl);
3064 if (err)
3065 goto free_dst;
3066
3067out:
3068 return xdst;
3069
3070free_dst:
3071 dst_release(dst1);
3072 xdst = ERR_PTR(err);
3073 goto out;
3074}
3075
3076static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
3077 const struct flowi *fl,
3078 u16 family, u8 dir,
3079 struct xfrm_flo *xflo, u32 if_id)
3080{
3081 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3082 int num_pols = 0, num_xfrms = 0, err;
3083 struct xfrm_dst *xdst;
3084
3085 /* Resolve policies to use if we couldn't get them from
3086 * previous cache entry */
3087 num_pols = 1;
3088 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
3089 err = xfrm_expand_policies(fl, family, pols,
3090 &num_pols, &num_xfrms);
3091 if (err < 0)
3092 goto inc_error;
3093 if (num_pols == 0)
3094 return NULL;
3095 if (num_xfrms <= 0)
3096 goto make_dummy_bundle;
3097
3098 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
3099 xflo->dst_orig);
3100 if (IS_ERR(xdst)) {
3101 err = PTR_ERR(xdst);
3102 if (err == -EREMOTE) {
3103 xfrm_pols_put(pols, num_pols);
3104 return NULL;
3105 }
3106
3107 if (err != -EAGAIN)
3108 goto error;
3109 goto make_dummy_bundle;
3110 } else if (xdst == NULL) {
3111 num_xfrms = 0;
3112 goto make_dummy_bundle;
3113 }
3114
3115 return xdst;
3116
3117make_dummy_bundle:
3118 /* We found policies, but there's no bundles to instantiate:
3119 * either because the policy blocks, has no transformations or
3120 * we could not build template (no xfrm_states).*/
3121 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
3122 if (IS_ERR(xdst)) {
3123 xfrm_pols_put(pols, num_pols);
3124 return ERR_CAST(xdst);
3125 }
3126 xdst->num_pols = num_pols;
3127 xdst->num_xfrms = num_xfrms;
3128 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
3129
3130 return xdst;
3131
3132inc_error:
3133 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3134error:
3135 xfrm_pols_put(pols, num_pols);
3136 return ERR_PTR(err);
3137}
3138
3139static struct dst_entry *make_blackhole(struct net *net, u16 family,
3140 struct dst_entry *dst_orig)
3141{
3142 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3143 struct dst_entry *ret;
3144
3145 if (!afinfo) {
3146 dst_release(dst_orig);
3147 return ERR_PTR(-EINVAL);
3148 } else {
3149 ret = afinfo->blackhole_route(net, dst_orig);
3150 }
3151 rcu_read_unlock();
3152
3153 return ret;
3154}
3155
3156/* Finds/creates a bundle for given flow and if_id
3157 *
3158 * At the moment we eat a raw IP route. Mostly to speed up lookups
3159 * on interfaces with disabled IPsec.
3160 *
3161 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3162 * compatibility
3163 */
3164struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3165 struct dst_entry *dst_orig,
3166 const struct flowi *fl,
3167 const struct sock *sk,
3168 int flags, u32 if_id)
3169{
3170 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3171 struct xfrm_dst *xdst;
3172 struct dst_entry *dst, *route;
3173 u16 family = dst_orig->ops->family;
3174 u8 dir = XFRM_POLICY_OUT;
3175 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3176
3177 dst = NULL;
3178 xdst = NULL;
3179 route = NULL;
3180
3181 sk = sk_const_to_full_sk(sk);
3182 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3183 num_pols = 1;
3184 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3185 if_id);
3186 err = xfrm_expand_policies(fl, family, pols,
3187 &num_pols, &num_xfrms);
3188 if (err < 0)
3189 goto dropdst;
3190
3191 if (num_pols) {
3192 if (num_xfrms <= 0) {
3193 drop_pols = num_pols;
3194 goto no_transform;
3195 }
3196
3197 xdst = xfrm_resolve_and_create_bundle(
3198 pols, num_pols, fl,
3199 family, dst_orig);
3200
3201 if (IS_ERR(xdst)) {
3202 xfrm_pols_put(pols, num_pols);
3203 err = PTR_ERR(xdst);
3204 if (err == -EREMOTE)
3205 goto nopol;
3206
3207 goto dropdst;
3208 } else if (xdst == NULL) {
3209 num_xfrms = 0;
3210 drop_pols = num_pols;
3211 goto no_transform;
3212 }
3213
3214 route = xdst->route;
3215 }
3216 }
3217
3218 if (xdst == NULL) {
3219 struct xfrm_flo xflo;
3220
3221 xflo.dst_orig = dst_orig;
3222 xflo.flags = flags;
3223
3224 /* To accelerate a bit... */
3225 if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3226 !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3227 goto nopol;
3228
3229 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3230 if (xdst == NULL)
3231 goto nopol;
3232 if (IS_ERR(xdst)) {
3233 err = PTR_ERR(xdst);
3234 goto dropdst;
3235 }
3236
3237 num_pols = xdst->num_pols;
3238 num_xfrms = xdst->num_xfrms;
3239 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3240 route = xdst->route;
3241 }
3242
3243 dst = &xdst->u.dst;
3244 if (route == NULL && num_xfrms > 0) {
3245 /* The only case when xfrm_bundle_lookup() returns a
3246 * bundle with null route, is when the template could
3247 * not be resolved. It means policies are there, but
3248 * bundle could not be created, since we don't yet
3249 * have the xfrm_state's. We need to wait for KM to
3250 * negotiate new SA's or bail out with error.*/
3251 if (net->xfrm.sysctl_larval_drop) {
3252 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3253 err = -EREMOTE;
3254 goto error;
3255 }
3256
3257 err = -EAGAIN;
3258
3259 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3260 goto error;
3261 }
3262
3263no_transform:
3264 if (num_pols == 0)
3265 goto nopol;
3266
3267 if ((flags & XFRM_LOOKUP_ICMP) &&
3268 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3269 err = -ENOENT;
3270 goto error;
3271 }
3272
3273 for (i = 0; i < num_pols; i++)
3274 WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds());
3275
3276 if (num_xfrms < 0) {
3277 /* Prohibit the flow */
3278 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3279 err = -EPERM;
3280 goto error;
3281 } else if (num_xfrms > 0) {
3282 /* Flow transformed */
3283 dst_release(dst_orig);
3284 } else {
3285 /* Flow passes untransformed */
3286 dst_release(dst);
3287 dst = dst_orig;
3288 }
3289
3290ok:
3291 xfrm_pols_put(pols, drop_pols);
3292 if (dst && dst->xfrm &&
3293 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3294 dst->flags |= DST_XFRM_TUNNEL;
3295 return dst;
3296
3297nopol:
3298 if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3299 net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3300 err = -EPERM;
3301 goto error;
3302 }
3303 if (!(flags & XFRM_LOOKUP_ICMP)) {
3304 dst = dst_orig;
3305 goto ok;
3306 }
3307 err = -ENOENT;
3308error:
3309 dst_release(dst);
3310dropdst:
3311 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3312 dst_release(dst_orig);
3313 xfrm_pols_put(pols, drop_pols);
3314 return ERR_PTR(err);
3315}
3316EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3317
3318/* Main function: finds/creates a bundle for given flow.
3319 *
3320 * At the moment we eat a raw IP route. Mostly to speed up lookups
3321 * on interfaces with disabled IPsec.
3322 */
3323struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3324 const struct flowi *fl, const struct sock *sk,
3325 int flags)
3326{
3327 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3328}
3329EXPORT_SYMBOL(xfrm_lookup);
3330
3331/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3332 * Otherwise we may send out blackholed packets.
3333 */
3334struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3335 const struct flowi *fl,
3336 const struct sock *sk, int flags)
3337{
3338 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3339 flags | XFRM_LOOKUP_QUEUE |
3340 XFRM_LOOKUP_KEEP_DST_REF);
3341
3342 if (PTR_ERR(dst) == -EREMOTE)
3343 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3344
3345 if (IS_ERR(dst))
3346 dst_release(dst_orig);
3347
3348 return dst;
3349}
3350EXPORT_SYMBOL(xfrm_lookup_route);
3351
3352static inline int
3353xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3354{
3355 struct sec_path *sp = skb_sec_path(skb);
3356 struct xfrm_state *x;
3357
3358 if (!sp || idx < 0 || idx >= sp->len)
3359 return 0;
3360 x = sp->xvec[idx];
3361 if (!x->type->reject)
3362 return 0;
3363 return x->type->reject(x, skb, fl);
3364}
3365
3366/* When skb is transformed back to its "native" form, we have to
3367 * check policy restrictions. At the moment we make this in maximally
3368 * stupid way. Shame on me. :-) Of course, connected sockets must
3369 * have policy cached at them.
3370 */
3371
3372static inline int
3373xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3374 unsigned short family, u32 if_id)
3375{
3376 if (xfrm_state_kern(x))
3377 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3378 return x->id.proto == tmpl->id.proto &&
3379 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3380 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3381 x->props.mode == tmpl->mode &&
3382 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3383 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3384 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3385 xfrm_state_addr_cmp(tmpl, x, family)) &&
3386 (if_id == 0 || if_id == x->if_id);
3387}
3388
3389/*
3390 * 0 or more than 0 is returned when validation is succeeded (either bypass
3391 * because of optional transport mode, or next index of the matched secpath
3392 * state with the template.
3393 * -1 is returned when no matching template is found.
3394 * Otherwise "-2 - errored_index" is returned.
3395 */
3396static inline int
3397xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3398 unsigned short family, u32 if_id)
3399{
3400 int idx = start;
3401
3402 if (tmpl->optional) {
3403 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3404 return start;
3405 } else
3406 start = -1;
3407 for (; idx < sp->len; idx++) {
3408 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
3409 return ++idx;
3410 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3411 if (idx < sp->verified_cnt) {
3412 /* Secpath entry previously verified, consider optional and
3413 * continue searching
3414 */
3415 continue;
3416 }
3417
3418 if (start == -1)
3419 start = -2-idx;
3420 break;
3421 }
3422 }
3423 return start;
3424}
3425
3426static void
3427decode_session4(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
3428{
3429 struct flowi4 *fl4 = &fl->u.ip4;
3430
3431 memset(fl4, 0, sizeof(struct flowi4));
3432
3433 if (reverse) {
3434 fl4->saddr = flkeys->addrs.ipv4.dst;
3435 fl4->daddr = flkeys->addrs.ipv4.src;
3436 fl4->fl4_sport = flkeys->ports.dst;
3437 fl4->fl4_dport = flkeys->ports.src;
3438 } else {
3439 fl4->saddr = flkeys->addrs.ipv4.src;
3440 fl4->daddr = flkeys->addrs.ipv4.dst;
3441 fl4->fl4_sport = flkeys->ports.src;
3442 fl4->fl4_dport = flkeys->ports.dst;
3443 }
3444
3445 switch (flkeys->basic.ip_proto) {
3446 case IPPROTO_GRE:
3447 fl4->fl4_gre_key = flkeys->gre.keyid;
3448 break;
3449 case IPPROTO_ICMP:
3450 fl4->fl4_icmp_type = flkeys->icmp.type;
3451 fl4->fl4_icmp_code = flkeys->icmp.code;
3452 break;
3453 }
3454
3455 fl4->flowi4_proto = flkeys->basic.ip_proto;
3456 fl4->flowi4_tos = flkeys->ip.tos & ~INET_ECN_MASK;
3457}
3458
3459#if IS_ENABLED(CONFIG_IPV6)
3460static void
3461decode_session6(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
3462{
3463 struct flowi6 *fl6 = &fl->u.ip6;
3464
3465 memset(fl6, 0, sizeof(struct flowi6));
3466
3467 if (reverse) {
3468 fl6->saddr = flkeys->addrs.ipv6.dst;
3469 fl6->daddr = flkeys->addrs.ipv6.src;
3470 fl6->fl6_sport = flkeys->ports.dst;
3471 fl6->fl6_dport = flkeys->ports.src;
3472 } else {
3473 fl6->saddr = flkeys->addrs.ipv6.src;
3474 fl6->daddr = flkeys->addrs.ipv6.dst;
3475 fl6->fl6_sport = flkeys->ports.src;
3476 fl6->fl6_dport = flkeys->ports.dst;
3477 }
3478
3479 switch (flkeys->basic.ip_proto) {
3480 case IPPROTO_GRE:
3481 fl6->fl6_gre_key = flkeys->gre.keyid;
3482 break;
3483 case IPPROTO_ICMPV6:
3484 fl6->fl6_icmp_type = flkeys->icmp.type;
3485 fl6->fl6_icmp_code = flkeys->icmp.code;
3486 break;
3487 }
3488
3489 fl6->flowi6_proto = flkeys->basic.ip_proto;
3490}
3491#endif
3492
3493int __xfrm_decode_session(struct net *net, struct sk_buff *skb, struct flowi *fl,
3494 unsigned int family, int reverse)
3495{
3496 struct xfrm_flow_keys flkeys;
3497
3498 memset(&flkeys, 0, sizeof(flkeys));
3499 __skb_flow_dissect(net, skb, &xfrm_session_dissector, &flkeys,
3500 NULL, 0, 0, 0, FLOW_DISSECTOR_F_STOP_AT_ENCAP);
3501
3502 switch (family) {
3503 case AF_INET:
3504 decode_session4(&flkeys, fl, reverse);
3505 break;
3506#if IS_ENABLED(CONFIG_IPV6)
3507 case AF_INET6:
3508 decode_session6(&flkeys, fl, reverse);
3509 break;
3510#endif
3511 default:
3512 return -EAFNOSUPPORT;
3513 }
3514
3515 fl->flowi_mark = skb->mark;
3516 if (reverse) {
3517 fl->flowi_oif = skb->skb_iif;
3518 } else {
3519 int oif = 0;
3520
3521 if (skb_dst(skb) && skb_dst(skb)->dev)
3522 oif = skb_dst(skb)->dev->ifindex;
3523
3524 fl->flowi_oif = oif;
3525 }
3526
3527 return security_xfrm_decode_session(skb, &fl->flowi_secid);
3528}
3529EXPORT_SYMBOL(__xfrm_decode_session);
3530
3531static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3532{
3533 for (; k < sp->len; k++) {
3534 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3535 *idxp = k;
3536 return 1;
3537 }
3538 }
3539
3540 return 0;
3541}
3542
3543static bool icmp_err_packet(const struct flowi *fl, unsigned short family)
3544{
3545 const struct flowi4 *fl4 = &fl->u.ip4;
3546
3547 if (family == AF_INET &&
3548 fl4->flowi4_proto == IPPROTO_ICMP &&
3549 (fl4->fl4_icmp_type == ICMP_DEST_UNREACH ||
3550 fl4->fl4_icmp_type == ICMP_TIME_EXCEEDED))
3551 return true;
3552
3553#if IS_ENABLED(CONFIG_IPV6)
3554 if (family == AF_INET6) {
3555 const struct flowi6 *fl6 = &fl->u.ip6;
3556
3557 if (fl6->flowi6_proto == IPPROTO_ICMPV6 &&
3558 (fl6->fl6_icmp_type == ICMPV6_DEST_UNREACH ||
3559 fl6->fl6_icmp_type == ICMPV6_PKT_TOOBIG ||
3560 fl6->fl6_icmp_type == ICMPV6_TIME_EXCEED))
3561 return true;
3562 }
3563#endif
3564 return false;
3565}
3566
3567static bool xfrm_icmp_flow_decode(struct sk_buff *skb, unsigned short family,
3568 const struct flowi *fl, struct flowi *fl1)
3569{
3570 bool ret = true;
3571 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
3572 int hl = family == AF_INET ? (sizeof(struct iphdr) + sizeof(struct icmphdr)) :
3573 (sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr));
3574
3575 if (!newskb)
3576 return true;
3577
3578 if (!pskb_pull(newskb, hl))
3579 goto out;
3580
3581 skb_reset_network_header(newskb);
3582
3583 if (xfrm_decode_session_reverse(dev_net(skb->dev), newskb, fl1, family) < 0)
3584 goto out;
3585
3586 fl1->flowi_oif = fl->flowi_oif;
3587 fl1->flowi_mark = fl->flowi_mark;
3588 fl1->flowi_tos = fl->flowi_tos;
3589 nf_nat_decode_session(newskb, fl1, family);
3590 ret = false;
3591
3592out:
3593 consume_skb(newskb);
3594 return ret;
3595}
3596
3597static bool xfrm_selector_inner_icmp_match(struct sk_buff *skb, unsigned short family,
3598 const struct xfrm_selector *sel,
3599 const struct flowi *fl)
3600{
3601 bool ret = false;
3602
3603 if (icmp_err_packet(fl, family)) {
3604 struct flowi fl1;
3605
3606 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3607 return ret;
3608
3609 ret = xfrm_selector_match(sel, &fl1, family);
3610 }
3611
3612 return ret;
3613}
3614
3615static inline struct
3616xfrm_policy *xfrm_in_fwd_icmp(struct sk_buff *skb,
3617 const struct flowi *fl, unsigned short family,
3618 u32 if_id)
3619{
3620 struct xfrm_policy *pol = NULL;
3621
3622 if (icmp_err_packet(fl, family)) {
3623 struct flowi fl1;
3624 struct net *net = dev_net(skb->dev);
3625
3626 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3627 return pol;
3628
3629 pol = xfrm_policy_lookup(net, &fl1, family, XFRM_POLICY_FWD, if_id);
3630 if (IS_ERR(pol))
3631 pol = NULL;
3632 }
3633
3634 return pol;
3635}
3636
3637static inline struct
3638dst_entry *xfrm_out_fwd_icmp(struct sk_buff *skb, struct flowi *fl,
3639 unsigned short family, struct dst_entry *dst)
3640{
3641 if (icmp_err_packet(fl, family)) {
3642 struct net *net = dev_net(skb->dev);
3643 struct dst_entry *dst2;
3644 struct flowi fl1;
3645
3646 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3647 return dst;
3648
3649 dst_hold(dst);
3650
3651 dst2 = xfrm_lookup(net, dst, &fl1, NULL, (XFRM_LOOKUP_QUEUE | XFRM_LOOKUP_ICMP));
3652
3653 if (IS_ERR(dst2))
3654 return dst;
3655
3656 if (dst2->xfrm) {
3657 dst_release(dst);
3658 dst = dst2;
3659 } else {
3660 dst_release(dst2);
3661 }
3662 }
3663
3664 return dst;
3665}
3666
3667int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3668 unsigned short family)
3669{
3670 struct net *net = dev_net(skb->dev);
3671 struct xfrm_policy *pol;
3672 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3673 int npols = 0;
3674 int xfrm_nr;
3675 int pi;
3676 int reverse;
3677 struct flowi fl;
3678 int xerr_idx = -1;
3679 const struct xfrm_if_cb *ifcb;
3680 struct sec_path *sp;
3681 u32 if_id = 0;
3682
3683 rcu_read_lock();
3684 ifcb = xfrm_if_get_cb();
3685
3686 if (ifcb) {
3687 struct xfrm_if_decode_session_result r;
3688
3689 if (ifcb->decode_session(skb, family, &r)) {
3690 if_id = r.if_id;
3691 net = r.net;
3692 }
3693 }
3694 rcu_read_unlock();
3695
3696 reverse = dir & ~XFRM_POLICY_MASK;
3697 dir &= XFRM_POLICY_MASK;
3698
3699 if (__xfrm_decode_session(net, skb, &fl, family, reverse) < 0) {
3700 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3701 return 0;
3702 }
3703
3704 nf_nat_decode_session(skb, &fl, family);
3705
3706 /* First, check used SA against their selectors. */
3707 sp = skb_sec_path(skb);
3708 if (sp) {
3709 int i;
3710
3711 for (i = sp->len - 1; i >= 0; i--) {
3712 struct xfrm_state *x = sp->xvec[i];
3713 int ret = 0;
3714
3715 if (!xfrm_selector_match(&x->sel, &fl, family)) {
3716 ret = 1;
3717 if (x->props.flags & XFRM_STATE_ICMP &&
3718 xfrm_selector_inner_icmp_match(skb, family, &x->sel, &fl))
3719 ret = 0;
3720 if (ret) {
3721 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3722 return 0;
3723 }
3724 }
3725 }
3726 }
3727
3728 pol = NULL;
3729 sk = sk_to_full_sk(sk);
3730 if (sk && sk->sk_policy[dir]) {
3731 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3732 if (IS_ERR(pol)) {
3733 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3734 return 0;
3735 }
3736 }
3737
3738 if (!pol)
3739 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3740
3741 if (IS_ERR(pol)) {
3742 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3743 return 0;
3744 }
3745
3746 if (!pol && dir == XFRM_POLICY_FWD)
3747 pol = xfrm_in_fwd_icmp(skb, &fl, family, if_id);
3748
3749 if (!pol) {
3750 const bool is_crypto_offload = sp &&
3751 (xfrm_input_state(skb)->xso.type == XFRM_DEV_OFFLOAD_CRYPTO);
3752
3753 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3754 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3755 return 0;
3756 }
3757
3758 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx) && !is_crypto_offload) {
3759 xfrm_secpath_reject(xerr_idx, skb, &fl);
3760 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3761 return 0;
3762 }
3763 return 1;
3764 }
3765
3766 /* This lockless write can happen from different cpus. */
3767 WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
3768
3769 pols[0] = pol;
3770 npols++;
3771#ifdef CONFIG_XFRM_SUB_POLICY
3772 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3773 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3774 &fl, family,
3775 XFRM_POLICY_IN, if_id);
3776 if (pols[1]) {
3777 if (IS_ERR(pols[1])) {
3778 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3779 xfrm_pol_put(pols[0]);
3780 return 0;
3781 }
3782 /* This write can happen from different cpus. */
3783 WRITE_ONCE(pols[1]->curlft.use_time,
3784 ktime_get_real_seconds());
3785 npols++;
3786 }
3787 }
3788#endif
3789
3790 if (pol->action == XFRM_POLICY_ALLOW) {
3791 static struct sec_path dummy;
3792 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3793 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3794 struct xfrm_tmpl **tpp = tp;
3795 int ti = 0;
3796 int i, k;
3797
3798 sp = skb_sec_path(skb);
3799 if (!sp)
3800 sp = &dummy;
3801
3802 for (pi = 0; pi < npols; pi++) {
3803 if (pols[pi] != pol &&
3804 pols[pi]->action != XFRM_POLICY_ALLOW) {
3805 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3806 goto reject;
3807 }
3808 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3809 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3810 goto reject_error;
3811 }
3812 for (i = 0; i < pols[pi]->xfrm_nr; i++)
3813 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3814 }
3815 xfrm_nr = ti;
3816
3817 if (npols > 1) {
3818 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3819 tpp = stp;
3820 }
3821
3822 /* For each tunnel xfrm, find the first matching tmpl.
3823 * For each tmpl before that, find corresponding xfrm.
3824 * Order is _important_. Later we will implement
3825 * some barriers, but at the moment barriers
3826 * are implied between each two transformations.
3827 * Upon success, marks secpath entries as having been
3828 * verified to allow them to be skipped in future policy
3829 * checks (e.g. nested tunnels).
3830 */
3831 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3832 k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
3833 if (k < 0) {
3834 if (k < -1)
3835 /* "-2 - errored_index" returned */
3836 xerr_idx = -(2+k);
3837 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3838 goto reject;
3839 }
3840 }
3841
3842 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3843 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3844 goto reject;
3845 }
3846
3847 xfrm_pols_put(pols, npols);
3848 sp->verified_cnt = k;
3849
3850 return 1;
3851 }
3852 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3853
3854reject:
3855 xfrm_secpath_reject(xerr_idx, skb, &fl);
3856reject_error:
3857 xfrm_pols_put(pols, npols);
3858 return 0;
3859}
3860EXPORT_SYMBOL(__xfrm_policy_check);
3861
3862int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3863{
3864 struct net *net = dev_net(skb->dev);
3865 struct flowi fl;
3866 struct dst_entry *dst;
3867 int res = 1;
3868
3869 if (xfrm_decode_session(net, skb, &fl, family) < 0) {
3870 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3871 return 0;
3872 }
3873
3874 skb_dst_force(skb);
3875 if (!skb_dst(skb)) {
3876 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3877 return 0;
3878 }
3879
3880 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3881 if (IS_ERR(dst)) {
3882 res = 0;
3883 dst = NULL;
3884 }
3885
3886 if (dst && !dst->xfrm)
3887 dst = xfrm_out_fwd_icmp(skb, &fl, family, dst);
3888
3889 skb_dst_set(skb, dst);
3890 return res;
3891}
3892EXPORT_SYMBOL(__xfrm_route_forward);
3893
3894/* Optimize later using cookies and generation ids. */
3895
3896static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3897{
3898 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3899 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3900 * get validated by dst_ops->check on every use. We do this
3901 * because when a normal route referenced by an XFRM dst is
3902 * obsoleted we do not go looking around for all parent
3903 * referencing XFRM dsts so that we can invalidate them. It
3904 * is just too much work. Instead we make the checks here on
3905 * every use. For example:
3906 *
3907 * XFRM dst A --> IPv4 dst X
3908 *
3909 * X is the "xdst->route" of A (X is also the "dst->path" of A
3910 * in this example). If X is marked obsolete, "A" will not
3911 * notice. That's what we are validating here via the
3912 * stale_bundle() check.
3913 *
3914 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3915 * be marked on it.
3916 * This will force stale_bundle() to fail on any xdst bundle with
3917 * this dst linked in it.
3918 */
3919 if (dst->obsolete < 0 && !stale_bundle(dst))
3920 return dst;
3921
3922 return NULL;
3923}
3924
3925static int stale_bundle(struct dst_entry *dst)
3926{
3927 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3928}
3929
3930void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3931{
3932 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3933 dst->dev = blackhole_netdev;
3934 dev_hold(dst->dev);
3935 dev_put(dev);
3936 }
3937}
3938EXPORT_SYMBOL(xfrm_dst_ifdown);
3939
3940static void xfrm_link_failure(struct sk_buff *skb)
3941{
3942 /* Impossible. Such dst must be popped before reaches point of failure. */
3943}
3944
3945static void xfrm_negative_advice(struct sock *sk, struct dst_entry *dst)
3946{
3947 if (dst->obsolete)
3948 sk_dst_reset(sk);
3949}
3950
3951static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3952{
3953 while (nr--) {
3954 struct xfrm_dst *xdst = bundle[nr];
3955 u32 pmtu, route_mtu_cached;
3956 struct dst_entry *dst;
3957
3958 dst = &xdst->u.dst;
3959 pmtu = dst_mtu(xfrm_dst_child(dst));
3960 xdst->child_mtu_cached = pmtu;
3961
3962 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3963
3964 route_mtu_cached = dst_mtu(xdst->route);
3965 xdst->route_mtu_cached = route_mtu_cached;
3966
3967 if (pmtu > route_mtu_cached)
3968 pmtu = route_mtu_cached;
3969
3970 dst_metric_set(dst, RTAX_MTU, pmtu);
3971 }
3972}
3973
3974/* Check that the bundle accepts the flow and its components are
3975 * still valid.
3976 */
3977
3978static int xfrm_bundle_ok(struct xfrm_dst *first)
3979{
3980 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3981 struct dst_entry *dst = &first->u.dst;
3982 struct xfrm_dst *xdst;
3983 int start_from, nr;
3984 u32 mtu;
3985
3986 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3987 (dst->dev && !netif_running(dst->dev)))
3988 return 0;
3989
3990 if (dst->flags & DST_XFRM_QUEUE)
3991 return 1;
3992
3993 start_from = nr = 0;
3994 do {
3995 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3996
3997 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3998 return 0;
3999 if (xdst->xfrm_genid != dst->xfrm->genid)
4000 return 0;
4001 if (xdst->num_pols > 0 &&
4002 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
4003 return 0;
4004
4005 bundle[nr++] = xdst;
4006
4007 mtu = dst_mtu(xfrm_dst_child(dst));
4008 if (xdst->child_mtu_cached != mtu) {
4009 start_from = nr;
4010 xdst->child_mtu_cached = mtu;
4011 }
4012
4013 if (!dst_check(xdst->route, xdst->route_cookie))
4014 return 0;
4015 mtu = dst_mtu(xdst->route);
4016 if (xdst->route_mtu_cached != mtu) {
4017 start_from = nr;
4018 xdst->route_mtu_cached = mtu;
4019 }
4020
4021 dst = xfrm_dst_child(dst);
4022 } while (dst->xfrm);
4023
4024 if (likely(!start_from))
4025 return 1;
4026
4027 xdst = bundle[start_from - 1];
4028 mtu = xdst->child_mtu_cached;
4029 while (start_from--) {
4030 dst = &xdst->u.dst;
4031
4032 mtu = xfrm_state_mtu(dst->xfrm, mtu);
4033 if (mtu > xdst->route_mtu_cached)
4034 mtu = xdst->route_mtu_cached;
4035 dst_metric_set(dst, RTAX_MTU, mtu);
4036 if (!start_from)
4037 break;
4038
4039 xdst = bundle[start_from - 1];
4040 xdst->child_mtu_cached = mtu;
4041 }
4042
4043 return 1;
4044}
4045
4046static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
4047{
4048 return dst_metric_advmss(xfrm_dst_path(dst));
4049}
4050
4051static unsigned int xfrm_mtu(const struct dst_entry *dst)
4052{
4053 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
4054
4055 return mtu ? : dst_mtu(xfrm_dst_path(dst));
4056}
4057
4058static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
4059 const void *daddr)
4060{
4061 while (dst->xfrm) {
4062 const struct xfrm_state *xfrm = dst->xfrm;
4063
4064 dst = xfrm_dst_child(dst);
4065
4066 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
4067 continue;
4068 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
4069 daddr = xfrm->coaddr;
4070 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
4071 daddr = &xfrm->id.daddr;
4072 }
4073 return daddr;
4074}
4075
4076static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
4077 struct sk_buff *skb,
4078 const void *daddr)
4079{
4080 const struct dst_entry *path = xfrm_dst_path(dst);
4081
4082 if (!skb)
4083 daddr = xfrm_get_dst_nexthop(dst, daddr);
4084 return path->ops->neigh_lookup(path, skb, daddr);
4085}
4086
4087static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
4088{
4089 const struct dst_entry *path = xfrm_dst_path(dst);
4090
4091 daddr = xfrm_get_dst_nexthop(dst, daddr);
4092 path->ops->confirm_neigh(path, daddr);
4093}
4094
4095int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
4096{
4097 int err = 0;
4098
4099 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
4100 return -EAFNOSUPPORT;
4101
4102 spin_lock(&xfrm_policy_afinfo_lock);
4103 if (unlikely(xfrm_policy_afinfo[family] != NULL))
4104 err = -EEXIST;
4105 else {
4106 struct dst_ops *dst_ops = afinfo->dst_ops;
4107 if (likely(dst_ops->kmem_cachep == NULL))
4108 dst_ops->kmem_cachep = xfrm_dst_cache;
4109 if (likely(dst_ops->check == NULL))
4110 dst_ops->check = xfrm_dst_check;
4111 if (likely(dst_ops->default_advmss == NULL))
4112 dst_ops->default_advmss = xfrm_default_advmss;
4113 if (likely(dst_ops->mtu == NULL))
4114 dst_ops->mtu = xfrm_mtu;
4115 if (likely(dst_ops->negative_advice == NULL))
4116 dst_ops->negative_advice = xfrm_negative_advice;
4117 if (likely(dst_ops->link_failure == NULL))
4118 dst_ops->link_failure = xfrm_link_failure;
4119 if (likely(dst_ops->neigh_lookup == NULL))
4120 dst_ops->neigh_lookup = xfrm_neigh_lookup;
4121 if (likely(!dst_ops->confirm_neigh))
4122 dst_ops->confirm_neigh = xfrm_confirm_neigh;
4123 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
4124 }
4125 spin_unlock(&xfrm_policy_afinfo_lock);
4126
4127 return err;
4128}
4129EXPORT_SYMBOL(xfrm_policy_register_afinfo);
4130
4131void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
4132{
4133 struct dst_ops *dst_ops = afinfo->dst_ops;
4134 int i;
4135
4136 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
4137 if (xfrm_policy_afinfo[i] != afinfo)
4138 continue;
4139 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
4140 break;
4141 }
4142
4143 synchronize_rcu();
4144
4145 dst_ops->kmem_cachep = NULL;
4146 dst_ops->check = NULL;
4147 dst_ops->negative_advice = NULL;
4148 dst_ops->link_failure = NULL;
4149}
4150EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
4151
4152void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
4153{
4154 spin_lock(&xfrm_if_cb_lock);
4155 rcu_assign_pointer(xfrm_if_cb, ifcb);
4156 spin_unlock(&xfrm_if_cb_lock);
4157}
4158EXPORT_SYMBOL(xfrm_if_register_cb);
4159
4160void xfrm_if_unregister_cb(void)
4161{
4162 RCU_INIT_POINTER(xfrm_if_cb, NULL);
4163 synchronize_rcu();
4164}
4165EXPORT_SYMBOL(xfrm_if_unregister_cb);
4166
4167#ifdef CONFIG_XFRM_STATISTICS
4168static int __net_init xfrm_statistics_init(struct net *net)
4169{
4170 int rv;
4171 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
4172 if (!net->mib.xfrm_statistics)
4173 return -ENOMEM;
4174 rv = xfrm_proc_init(net);
4175 if (rv < 0)
4176 free_percpu(net->mib.xfrm_statistics);
4177 return rv;
4178}
4179
4180static void xfrm_statistics_fini(struct net *net)
4181{
4182 xfrm_proc_fini(net);
4183 free_percpu(net->mib.xfrm_statistics);
4184}
4185#else
4186static int __net_init xfrm_statistics_init(struct net *net)
4187{
4188 return 0;
4189}
4190
4191static void xfrm_statistics_fini(struct net *net)
4192{
4193}
4194#endif
4195
4196static int __net_init xfrm_policy_init(struct net *net)
4197{
4198 unsigned int hmask, sz;
4199 int dir, err;
4200
4201 if (net_eq(net, &init_net)) {
4202 xfrm_dst_cache = KMEM_CACHE(xfrm_dst, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
4203 err = rhashtable_init(&xfrm_policy_inexact_table,
4204 &xfrm_pol_inexact_params);
4205 BUG_ON(err);
4206 }
4207
4208 hmask = 8 - 1;
4209 sz = (hmask+1) * sizeof(struct hlist_head);
4210
4211 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4212 if (!net->xfrm.policy_byidx)
4213 goto out_byidx;
4214 net->xfrm.policy_idx_hmask = hmask;
4215
4216 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4217 struct xfrm_policy_hash *htab;
4218
4219 net->xfrm.policy_count[dir] = 0;
4220 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4221
4222 htab = &net->xfrm.policy_bydst[dir];
4223 htab->table = xfrm_hash_alloc(sz);
4224 if (!htab->table)
4225 goto out_bydst;
4226 htab->hmask = hmask;
4227 htab->dbits4 = 32;
4228 htab->sbits4 = 32;
4229 htab->dbits6 = 128;
4230 htab->sbits6 = 128;
4231 }
4232 net->xfrm.policy_hthresh.lbits4 = 32;
4233 net->xfrm.policy_hthresh.rbits4 = 32;
4234 net->xfrm.policy_hthresh.lbits6 = 128;
4235 net->xfrm.policy_hthresh.rbits6 = 128;
4236
4237 seqlock_init(&net->xfrm.policy_hthresh.lock);
4238
4239 INIT_LIST_HEAD(&net->xfrm.policy_all);
4240 INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4241 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4242 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4243 return 0;
4244
4245out_bydst:
4246 for (dir--; dir >= 0; dir--) {
4247 struct xfrm_policy_hash *htab;
4248
4249 htab = &net->xfrm.policy_bydst[dir];
4250 xfrm_hash_free(htab->table, sz);
4251 }
4252 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4253out_byidx:
4254 return -ENOMEM;
4255}
4256
4257static void xfrm_policy_fini(struct net *net)
4258{
4259 struct xfrm_pol_inexact_bin *b, *t;
4260 unsigned int sz;
4261 int dir;
4262
4263 flush_work(&net->xfrm.policy_hash_work);
4264#ifdef CONFIG_XFRM_SUB_POLICY
4265 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4266#endif
4267 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4268
4269 WARN_ON(!list_empty(&net->xfrm.policy_all));
4270
4271 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4272 struct xfrm_policy_hash *htab;
4273
4274 htab = &net->xfrm.policy_bydst[dir];
4275 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4276 WARN_ON(!hlist_empty(htab->table));
4277 xfrm_hash_free(htab->table, sz);
4278 }
4279
4280 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4281 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4282 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4283
4284 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4285 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4286 __xfrm_policy_inexact_prune_bin(b, true);
4287 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4288}
4289
4290static int __net_init xfrm_net_init(struct net *net)
4291{
4292 int rv;
4293
4294 /* Initialize the per-net locks here */
4295 spin_lock_init(&net->xfrm.xfrm_state_lock);
4296 spin_lock_init(&net->xfrm.xfrm_policy_lock);
4297 seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4298 mutex_init(&net->xfrm.xfrm_cfg_mutex);
4299 net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4300 net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4301 net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4302
4303 rv = xfrm_statistics_init(net);
4304 if (rv < 0)
4305 goto out_statistics;
4306 rv = xfrm_state_init(net);
4307 if (rv < 0)
4308 goto out_state;
4309 rv = xfrm_policy_init(net);
4310 if (rv < 0)
4311 goto out_policy;
4312 rv = xfrm_sysctl_init(net);
4313 if (rv < 0)
4314 goto out_sysctl;
4315
4316 rv = xfrm_nat_keepalive_net_init(net);
4317 if (rv < 0)
4318 goto out_nat_keepalive;
4319
4320 return 0;
4321
4322out_nat_keepalive:
4323 xfrm_sysctl_fini(net);
4324out_sysctl:
4325 xfrm_policy_fini(net);
4326out_policy:
4327 xfrm_state_fini(net);
4328out_state:
4329 xfrm_statistics_fini(net);
4330out_statistics:
4331 return rv;
4332}
4333
4334static void __net_exit xfrm_net_exit(struct net *net)
4335{
4336 xfrm_nat_keepalive_net_fini(net);
4337 xfrm_sysctl_fini(net);
4338 xfrm_policy_fini(net);
4339 xfrm_state_fini(net);
4340 xfrm_statistics_fini(net);
4341}
4342
4343static struct pernet_operations __net_initdata xfrm_net_ops = {
4344 .init = xfrm_net_init,
4345 .exit = xfrm_net_exit,
4346};
4347
4348static const struct flow_dissector_key xfrm_flow_dissector_keys[] = {
4349 {
4350 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
4351 .offset = offsetof(struct xfrm_flow_keys, control),
4352 },
4353 {
4354 .key_id = FLOW_DISSECTOR_KEY_BASIC,
4355 .offset = offsetof(struct xfrm_flow_keys, basic),
4356 },
4357 {
4358 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
4359 .offset = offsetof(struct xfrm_flow_keys, addrs.ipv4),
4360 },
4361 {
4362 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
4363 .offset = offsetof(struct xfrm_flow_keys, addrs.ipv6),
4364 },
4365 {
4366 .key_id = FLOW_DISSECTOR_KEY_PORTS,
4367 .offset = offsetof(struct xfrm_flow_keys, ports),
4368 },
4369 {
4370 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
4371 .offset = offsetof(struct xfrm_flow_keys, gre),
4372 },
4373 {
4374 .key_id = FLOW_DISSECTOR_KEY_IP,
4375 .offset = offsetof(struct xfrm_flow_keys, ip),
4376 },
4377 {
4378 .key_id = FLOW_DISSECTOR_KEY_ICMP,
4379 .offset = offsetof(struct xfrm_flow_keys, icmp),
4380 },
4381};
4382
4383void __init xfrm_init(void)
4384{
4385 skb_flow_dissector_init(&xfrm_session_dissector,
4386 xfrm_flow_dissector_keys,
4387 ARRAY_SIZE(xfrm_flow_dissector_keys));
4388
4389 register_pernet_subsys(&xfrm_net_ops);
4390 xfrm_dev_init();
4391 xfrm_input_init();
4392
4393#ifdef CONFIG_XFRM_ESPINTCP
4394 espintcp_init();
4395#endif
4396
4397 register_xfrm_state_bpf();
4398 xfrm_nat_keepalive_init(AF_INET);
4399}
4400
4401#ifdef CONFIG_AUDITSYSCALL
4402static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4403 struct audit_buffer *audit_buf)
4404{
4405 struct xfrm_sec_ctx *ctx = xp->security;
4406 struct xfrm_selector *sel = &xp->selector;
4407
4408 if (ctx)
4409 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4410 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4411
4412 switch (sel->family) {
4413 case AF_INET:
4414 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4415 if (sel->prefixlen_s != 32)
4416 audit_log_format(audit_buf, " src_prefixlen=%d",
4417 sel->prefixlen_s);
4418 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4419 if (sel->prefixlen_d != 32)
4420 audit_log_format(audit_buf, " dst_prefixlen=%d",
4421 sel->prefixlen_d);
4422 break;
4423 case AF_INET6:
4424 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4425 if (sel->prefixlen_s != 128)
4426 audit_log_format(audit_buf, " src_prefixlen=%d",
4427 sel->prefixlen_s);
4428 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4429 if (sel->prefixlen_d != 128)
4430 audit_log_format(audit_buf, " dst_prefixlen=%d",
4431 sel->prefixlen_d);
4432 break;
4433 }
4434}
4435
4436void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4437{
4438 struct audit_buffer *audit_buf;
4439
4440 audit_buf = xfrm_audit_start("SPD-add");
4441 if (audit_buf == NULL)
4442 return;
4443 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4444 audit_log_format(audit_buf, " res=%u", result);
4445 xfrm_audit_common_policyinfo(xp, audit_buf);
4446 audit_log_end(audit_buf);
4447}
4448EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4449
4450void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4451 bool task_valid)
4452{
4453 struct audit_buffer *audit_buf;
4454
4455 audit_buf = xfrm_audit_start("SPD-delete");
4456 if (audit_buf == NULL)
4457 return;
4458 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4459 audit_log_format(audit_buf, " res=%u", result);
4460 xfrm_audit_common_policyinfo(xp, audit_buf);
4461 audit_log_end(audit_buf);
4462}
4463EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4464#endif
4465
4466#ifdef CONFIG_XFRM_MIGRATE
4467static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4468 u8 dir, u8 type, struct net *net, u32 if_id)
4469{
4470 struct xfrm_policy *pol;
4471 struct flowi fl;
4472
4473 memset(&fl, 0, sizeof(fl));
4474
4475 fl.flowi_proto = sel->proto;
4476
4477 switch (sel->family) {
4478 case AF_INET:
4479 fl.u.ip4.saddr = sel->saddr.a4;
4480 fl.u.ip4.daddr = sel->daddr.a4;
4481 if (sel->proto == IPSEC_ULPROTO_ANY)
4482 break;
4483 fl.u.flowi4_oif = sel->ifindex;
4484 fl.u.ip4.fl4_sport = sel->sport;
4485 fl.u.ip4.fl4_dport = sel->dport;
4486 break;
4487 case AF_INET6:
4488 fl.u.ip6.saddr = sel->saddr.in6;
4489 fl.u.ip6.daddr = sel->daddr.in6;
4490 if (sel->proto == IPSEC_ULPROTO_ANY)
4491 break;
4492 fl.u.flowi6_oif = sel->ifindex;
4493 fl.u.ip6.fl4_sport = sel->sport;
4494 fl.u.ip6.fl4_dport = sel->dport;
4495 break;
4496 default:
4497 return ERR_PTR(-EAFNOSUPPORT);
4498 }
4499
4500 rcu_read_lock();
4501
4502 pol = xfrm_policy_lookup_bytype(net, type, &fl, sel->family, dir, if_id);
4503 if (IS_ERR_OR_NULL(pol))
4504 goto out_unlock;
4505
4506 if (!xfrm_pol_hold_rcu(pol))
4507 pol = NULL;
4508out_unlock:
4509 rcu_read_unlock();
4510 return pol;
4511}
4512
4513static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4514{
4515 int match = 0;
4516
4517 if (t->mode == m->mode && t->id.proto == m->proto &&
4518 (m->reqid == 0 || t->reqid == m->reqid)) {
4519 switch (t->mode) {
4520 case XFRM_MODE_TUNNEL:
4521 case XFRM_MODE_BEET:
4522 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4523 m->old_family) &&
4524 xfrm_addr_equal(&t->saddr, &m->old_saddr,
4525 m->old_family)) {
4526 match = 1;
4527 }
4528 break;
4529 case XFRM_MODE_TRANSPORT:
4530 /* in case of transport mode, template does not store
4531 any IP addresses, hence we just compare mode and
4532 protocol */
4533 match = 1;
4534 break;
4535 default:
4536 break;
4537 }
4538 }
4539 return match;
4540}
4541
4542/* update endpoint address(es) of template(s) */
4543static int xfrm_policy_migrate(struct xfrm_policy *pol,
4544 struct xfrm_migrate *m, int num_migrate,
4545 struct netlink_ext_ack *extack)
4546{
4547 struct xfrm_migrate *mp;
4548 int i, j, n = 0;
4549
4550 write_lock_bh(&pol->lock);
4551 if (unlikely(pol->walk.dead)) {
4552 /* target policy has been deleted */
4553 NL_SET_ERR_MSG(extack, "Target policy not found");
4554 write_unlock_bh(&pol->lock);
4555 return -ENOENT;
4556 }
4557
4558 for (i = 0; i < pol->xfrm_nr; i++) {
4559 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4560 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4561 continue;
4562 n++;
4563 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4564 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4565 continue;
4566 /* update endpoints */
4567 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4568 sizeof(pol->xfrm_vec[i].id.daddr));
4569 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4570 sizeof(pol->xfrm_vec[i].saddr));
4571 pol->xfrm_vec[i].encap_family = mp->new_family;
4572 /* flush bundles */
4573 atomic_inc(&pol->genid);
4574 }
4575 }
4576
4577 write_unlock_bh(&pol->lock);
4578
4579 if (!n)
4580 return -ENODATA;
4581
4582 return 0;
4583}
4584
4585static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
4586 struct netlink_ext_ack *extack)
4587{
4588 int i, j;
4589
4590 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
4591 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
4592 return -EINVAL;
4593 }
4594
4595 for (i = 0; i < num_migrate; i++) {
4596 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4597 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
4598 NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
4599 return -EINVAL;
4600 }
4601
4602 /* check if there is any duplicated entry */
4603 for (j = i + 1; j < num_migrate; j++) {
4604 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4605 sizeof(m[i].old_daddr)) &&
4606 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4607 sizeof(m[i].old_saddr)) &&
4608 m[i].proto == m[j].proto &&
4609 m[i].mode == m[j].mode &&
4610 m[i].reqid == m[j].reqid &&
4611 m[i].old_family == m[j].old_family) {
4612 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
4613 return -EINVAL;
4614 }
4615 }
4616 }
4617
4618 return 0;
4619}
4620
4621int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4622 struct xfrm_migrate *m, int num_migrate,
4623 struct xfrm_kmaddress *k, struct net *net,
4624 struct xfrm_encap_tmpl *encap, u32 if_id,
4625 struct netlink_ext_ack *extack)
4626{
4627 int i, err, nx_cur = 0, nx_new = 0;
4628 struct xfrm_policy *pol = NULL;
4629 struct xfrm_state *x, *xc;
4630 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4631 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4632 struct xfrm_migrate *mp;
4633
4634 /* Stage 0 - sanity checks */
4635 err = xfrm_migrate_check(m, num_migrate, extack);
4636 if (err < 0)
4637 goto out;
4638
4639 if (dir >= XFRM_POLICY_MAX) {
4640 NL_SET_ERR_MSG(extack, "Invalid policy direction");
4641 err = -EINVAL;
4642 goto out;
4643 }
4644
4645 /* Stage 1 - find policy */
4646 pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
4647 if (IS_ERR_OR_NULL(pol)) {
4648 NL_SET_ERR_MSG(extack, "Target policy not found");
4649 err = IS_ERR(pol) ? PTR_ERR(pol) : -ENOENT;
4650 goto out;
4651 }
4652
4653 /* Stage 2 - find and update state(s) */
4654 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4655 if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4656 x_cur[nx_cur] = x;
4657 nx_cur++;
4658 xc = xfrm_state_migrate(x, mp, encap);
4659 if (xc) {
4660 x_new[nx_new] = xc;
4661 nx_new++;
4662 } else {
4663 err = -ENODATA;
4664 goto restore_state;
4665 }
4666 }
4667 }
4668
4669 /* Stage 3 - update policy */
4670 err = xfrm_policy_migrate(pol, m, num_migrate, extack);
4671 if (err < 0)
4672 goto restore_state;
4673
4674 /* Stage 4 - delete old state(s) */
4675 if (nx_cur) {
4676 xfrm_states_put(x_cur, nx_cur);
4677 xfrm_states_delete(x_cur, nx_cur);
4678 }
4679
4680 /* Stage 5 - announce */
4681 km_migrate(sel, dir, type, m, num_migrate, k, encap);
4682
4683 xfrm_pol_put(pol);
4684
4685 return 0;
4686out:
4687 return err;
4688
4689restore_state:
4690 if (pol)
4691 xfrm_pol_put(pol);
4692 if (nx_cur)
4693 xfrm_states_put(x_cur, nx_cur);
4694 if (nx_new)
4695 xfrm_states_delete(x_new, nx_new);
4696
4697 return err;
4698}
4699EXPORT_SYMBOL(xfrm_migrate);
4700#endif
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/cpu.h>
28#include <linux/audit.h>
29#include <net/dst.h>
30#include <net/flow.h>
31#include <net/xfrm.h>
32#include <net/ip.h>
33#ifdef CONFIG_XFRM_STATISTICS
34#include <net/snmp.h>
35#endif
36
37#include "xfrm_hash.h"
38
39#define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
40#define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
41#define XFRM_MAX_QUEUE_LEN 100
42
43struct xfrm_flo {
44 struct dst_entry *dst_orig;
45 u8 flags;
46};
47
48static DEFINE_PER_CPU(struct xfrm_dst *, xfrm_last_dst);
49static struct work_struct *xfrm_pcpu_work __read_mostly;
50static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
51static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
52 __read_mostly;
53
54static struct kmem_cache *xfrm_dst_cache __ro_after_init;
55static __read_mostly seqcount_t xfrm_policy_hash_generation;
56
57static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
58static int stale_bundle(struct dst_entry *dst);
59static int xfrm_bundle_ok(struct xfrm_dst *xdst);
60static void xfrm_policy_queue_process(struct timer_list *t);
61
62static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
63static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
64 int dir);
65
66static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
67{
68 return refcount_inc_not_zero(&policy->refcnt);
69}
70
71static inline bool
72__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
73{
74 const struct flowi4 *fl4 = &fl->u.ip4;
75
76 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
77 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
78 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
79 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
80 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
81 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
82}
83
84static inline bool
85__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
86{
87 const struct flowi6 *fl6 = &fl->u.ip6;
88
89 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
90 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
91 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
92 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
93 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
94 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
95}
96
97bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
98 unsigned short family)
99{
100 switch (family) {
101 case AF_INET:
102 return __xfrm4_selector_match(sel, fl);
103 case AF_INET6:
104 return __xfrm6_selector_match(sel, fl);
105 }
106 return false;
107}
108
109static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
110{
111 const struct xfrm_policy_afinfo *afinfo;
112
113 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
114 return NULL;
115 rcu_read_lock();
116 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
117 if (unlikely(!afinfo))
118 rcu_read_unlock();
119 return afinfo;
120}
121
122struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
123 const xfrm_address_t *saddr,
124 const xfrm_address_t *daddr,
125 int family, u32 mark)
126{
127 const struct xfrm_policy_afinfo *afinfo;
128 struct dst_entry *dst;
129
130 afinfo = xfrm_policy_get_afinfo(family);
131 if (unlikely(afinfo == NULL))
132 return ERR_PTR(-EAFNOSUPPORT);
133
134 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
135
136 rcu_read_unlock();
137
138 return dst;
139}
140EXPORT_SYMBOL(__xfrm_dst_lookup);
141
142static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
143 int tos, int oif,
144 xfrm_address_t *prev_saddr,
145 xfrm_address_t *prev_daddr,
146 int family, u32 mark)
147{
148 struct net *net = xs_net(x);
149 xfrm_address_t *saddr = &x->props.saddr;
150 xfrm_address_t *daddr = &x->id.daddr;
151 struct dst_entry *dst;
152
153 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
154 saddr = x->coaddr;
155 daddr = prev_daddr;
156 }
157 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
158 saddr = prev_saddr;
159 daddr = x->coaddr;
160 }
161
162 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
163
164 if (!IS_ERR(dst)) {
165 if (prev_saddr != saddr)
166 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
167 if (prev_daddr != daddr)
168 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
169 }
170
171 return dst;
172}
173
174static inline unsigned long make_jiffies(long secs)
175{
176 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
177 return MAX_SCHEDULE_TIMEOUT-1;
178 else
179 return secs*HZ;
180}
181
182static void xfrm_policy_timer(struct timer_list *t)
183{
184 struct xfrm_policy *xp = from_timer(xp, t, timer);
185 unsigned long now = get_seconds();
186 long next = LONG_MAX;
187 int warn = 0;
188 int dir;
189
190 read_lock(&xp->lock);
191
192 if (unlikely(xp->walk.dead))
193 goto out;
194
195 dir = xfrm_policy_id2dir(xp->index);
196
197 if (xp->lft.hard_add_expires_seconds) {
198 long tmo = xp->lft.hard_add_expires_seconds +
199 xp->curlft.add_time - now;
200 if (tmo <= 0)
201 goto expired;
202 if (tmo < next)
203 next = tmo;
204 }
205 if (xp->lft.hard_use_expires_seconds) {
206 long tmo = xp->lft.hard_use_expires_seconds +
207 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
208 if (tmo <= 0)
209 goto expired;
210 if (tmo < next)
211 next = tmo;
212 }
213 if (xp->lft.soft_add_expires_seconds) {
214 long tmo = xp->lft.soft_add_expires_seconds +
215 xp->curlft.add_time - now;
216 if (tmo <= 0) {
217 warn = 1;
218 tmo = XFRM_KM_TIMEOUT;
219 }
220 if (tmo < next)
221 next = tmo;
222 }
223 if (xp->lft.soft_use_expires_seconds) {
224 long tmo = xp->lft.soft_use_expires_seconds +
225 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
226 if (tmo <= 0) {
227 warn = 1;
228 tmo = XFRM_KM_TIMEOUT;
229 }
230 if (tmo < next)
231 next = tmo;
232 }
233
234 if (warn)
235 km_policy_expired(xp, dir, 0, 0);
236 if (next != LONG_MAX &&
237 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
238 xfrm_pol_hold(xp);
239
240out:
241 read_unlock(&xp->lock);
242 xfrm_pol_put(xp);
243 return;
244
245expired:
246 read_unlock(&xp->lock);
247 if (!xfrm_policy_delete(xp, dir))
248 km_policy_expired(xp, dir, 1, 0);
249 xfrm_pol_put(xp);
250}
251
252/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
253 * SPD calls.
254 */
255
256struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
257{
258 struct xfrm_policy *policy;
259
260 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
261
262 if (policy) {
263 write_pnet(&policy->xp_net, net);
264 INIT_LIST_HEAD(&policy->walk.all);
265 INIT_HLIST_NODE(&policy->bydst);
266 INIT_HLIST_NODE(&policy->byidx);
267 rwlock_init(&policy->lock);
268 refcount_set(&policy->refcnt, 1);
269 skb_queue_head_init(&policy->polq.hold_queue);
270 timer_setup(&policy->timer, xfrm_policy_timer, 0);
271 timer_setup(&policy->polq.hold_timer,
272 xfrm_policy_queue_process, 0);
273 }
274 return policy;
275}
276EXPORT_SYMBOL(xfrm_policy_alloc);
277
278static void xfrm_policy_destroy_rcu(struct rcu_head *head)
279{
280 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
281
282 security_xfrm_policy_free(policy->security);
283 kfree(policy);
284}
285
286/* Destroy xfrm_policy: descendant resources must be released to this moment. */
287
288void xfrm_policy_destroy(struct xfrm_policy *policy)
289{
290 BUG_ON(!policy->walk.dead);
291
292 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
293 BUG();
294
295 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
296}
297EXPORT_SYMBOL(xfrm_policy_destroy);
298
299/* Rule must be locked. Release descendant resources, announce
300 * entry dead. The rule must be unlinked from lists to the moment.
301 */
302
303static void xfrm_policy_kill(struct xfrm_policy *policy)
304{
305 policy->walk.dead = 1;
306
307 atomic_inc(&policy->genid);
308
309 if (del_timer(&policy->polq.hold_timer))
310 xfrm_pol_put(policy);
311 skb_queue_purge(&policy->polq.hold_queue);
312
313 if (del_timer(&policy->timer))
314 xfrm_pol_put(policy);
315
316 xfrm_pol_put(policy);
317}
318
319static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
320
321static inline unsigned int idx_hash(struct net *net, u32 index)
322{
323 return __idx_hash(index, net->xfrm.policy_idx_hmask);
324}
325
326/* calculate policy hash thresholds */
327static void __get_hash_thresh(struct net *net,
328 unsigned short family, int dir,
329 u8 *dbits, u8 *sbits)
330{
331 switch (family) {
332 case AF_INET:
333 *dbits = net->xfrm.policy_bydst[dir].dbits4;
334 *sbits = net->xfrm.policy_bydst[dir].sbits4;
335 break;
336
337 case AF_INET6:
338 *dbits = net->xfrm.policy_bydst[dir].dbits6;
339 *sbits = net->xfrm.policy_bydst[dir].sbits6;
340 break;
341
342 default:
343 *dbits = 0;
344 *sbits = 0;
345 }
346}
347
348static struct hlist_head *policy_hash_bysel(struct net *net,
349 const struct xfrm_selector *sel,
350 unsigned short family, int dir)
351{
352 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
353 unsigned int hash;
354 u8 dbits;
355 u8 sbits;
356
357 __get_hash_thresh(net, family, dir, &dbits, &sbits);
358 hash = __sel_hash(sel, family, hmask, dbits, sbits);
359
360 if (hash == hmask + 1)
361 return &net->xfrm.policy_inexact[dir];
362
363 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
364 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
365}
366
367static struct hlist_head *policy_hash_direct(struct net *net,
368 const xfrm_address_t *daddr,
369 const xfrm_address_t *saddr,
370 unsigned short family, int dir)
371{
372 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
373 unsigned int hash;
374 u8 dbits;
375 u8 sbits;
376
377 __get_hash_thresh(net, family, dir, &dbits, &sbits);
378 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
379
380 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
381 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
382}
383
384static void xfrm_dst_hash_transfer(struct net *net,
385 struct hlist_head *list,
386 struct hlist_head *ndsttable,
387 unsigned int nhashmask,
388 int dir)
389{
390 struct hlist_node *tmp, *entry0 = NULL;
391 struct xfrm_policy *pol;
392 unsigned int h0 = 0;
393 u8 dbits;
394 u8 sbits;
395
396redo:
397 hlist_for_each_entry_safe(pol, tmp, list, bydst) {
398 unsigned int h;
399
400 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
401 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
402 pol->family, nhashmask, dbits, sbits);
403 if (!entry0) {
404 hlist_del_rcu(&pol->bydst);
405 hlist_add_head_rcu(&pol->bydst, ndsttable + h);
406 h0 = h;
407 } else {
408 if (h != h0)
409 continue;
410 hlist_del_rcu(&pol->bydst);
411 hlist_add_behind_rcu(&pol->bydst, entry0);
412 }
413 entry0 = &pol->bydst;
414 }
415 if (!hlist_empty(list)) {
416 entry0 = NULL;
417 goto redo;
418 }
419}
420
421static void xfrm_idx_hash_transfer(struct hlist_head *list,
422 struct hlist_head *nidxtable,
423 unsigned int nhashmask)
424{
425 struct hlist_node *tmp;
426 struct xfrm_policy *pol;
427
428 hlist_for_each_entry_safe(pol, tmp, list, byidx) {
429 unsigned int h;
430
431 h = __idx_hash(pol->index, nhashmask);
432 hlist_add_head(&pol->byidx, nidxtable+h);
433 }
434}
435
436static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
437{
438 return ((old_hmask + 1) << 1) - 1;
439}
440
441static void xfrm_bydst_resize(struct net *net, int dir)
442{
443 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
444 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
445 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
446 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
447 struct hlist_head *odst;
448 int i;
449
450 if (!ndst)
451 return;
452
453 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
454 write_seqcount_begin(&xfrm_policy_hash_generation);
455
456 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
457 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
458
459 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
460 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
461
462 for (i = hmask; i >= 0; i--)
463 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
464
465 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
466 net->xfrm.policy_bydst[dir].hmask = nhashmask;
467
468 write_seqcount_end(&xfrm_policy_hash_generation);
469 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
470
471 synchronize_rcu();
472
473 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
474}
475
476static void xfrm_byidx_resize(struct net *net, int total)
477{
478 unsigned int hmask = net->xfrm.policy_idx_hmask;
479 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
480 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
481 struct hlist_head *oidx = net->xfrm.policy_byidx;
482 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
483 int i;
484
485 if (!nidx)
486 return;
487
488 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
489
490 for (i = hmask; i >= 0; i--)
491 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
492
493 net->xfrm.policy_byidx = nidx;
494 net->xfrm.policy_idx_hmask = nhashmask;
495
496 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
497
498 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
499}
500
501static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
502{
503 unsigned int cnt = net->xfrm.policy_count[dir];
504 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
505
506 if (total)
507 *total += cnt;
508
509 if ((hmask + 1) < xfrm_policy_hashmax &&
510 cnt > hmask)
511 return 1;
512
513 return 0;
514}
515
516static inline int xfrm_byidx_should_resize(struct net *net, int total)
517{
518 unsigned int hmask = net->xfrm.policy_idx_hmask;
519
520 if ((hmask + 1) < xfrm_policy_hashmax &&
521 total > hmask)
522 return 1;
523
524 return 0;
525}
526
527void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
528{
529 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
530 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
531 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
532 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
533 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
534 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
535 si->spdhcnt = net->xfrm.policy_idx_hmask;
536 si->spdhmcnt = xfrm_policy_hashmax;
537}
538EXPORT_SYMBOL(xfrm_spd_getinfo);
539
540static DEFINE_MUTEX(hash_resize_mutex);
541static void xfrm_hash_resize(struct work_struct *work)
542{
543 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
544 int dir, total;
545
546 mutex_lock(&hash_resize_mutex);
547
548 total = 0;
549 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
550 if (xfrm_bydst_should_resize(net, dir, &total))
551 xfrm_bydst_resize(net, dir);
552 }
553 if (xfrm_byidx_should_resize(net, total))
554 xfrm_byidx_resize(net, total);
555
556 mutex_unlock(&hash_resize_mutex);
557}
558
559static void xfrm_hash_rebuild(struct work_struct *work)
560{
561 struct net *net = container_of(work, struct net,
562 xfrm.policy_hthresh.work);
563 unsigned int hmask;
564 struct xfrm_policy *pol;
565 struct xfrm_policy *policy;
566 struct hlist_head *chain;
567 struct hlist_head *odst;
568 struct hlist_node *newpos;
569 int i;
570 int dir;
571 unsigned seq;
572 u8 lbits4, rbits4, lbits6, rbits6;
573
574 mutex_lock(&hash_resize_mutex);
575
576 /* read selector prefixlen thresholds */
577 do {
578 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
579
580 lbits4 = net->xfrm.policy_hthresh.lbits4;
581 rbits4 = net->xfrm.policy_hthresh.rbits4;
582 lbits6 = net->xfrm.policy_hthresh.lbits6;
583 rbits6 = net->xfrm.policy_hthresh.rbits6;
584 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
585
586 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
587
588 /* reset the bydst and inexact table in all directions */
589 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
590 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
591 hmask = net->xfrm.policy_bydst[dir].hmask;
592 odst = net->xfrm.policy_bydst[dir].table;
593 for (i = hmask; i >= 0; i--)
594 INIT_HLIST_HEAD(odst + i);
595 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
596 /* dir out => dst = remote, src = local */
597 net->xfrm.policy_bydst[dir].dbits4 = rbits4;
598 net->xfrm.policy_bydst[dir].sbits4 = lbits4;
599 net->xfrm.policy_bydst[dir].dbits6 = rbits6;
600 net->xfrm.policy_bydst[dir].sbits6 = lbits6;
601 } else {
602 /* dir in/fwd => dst = local, src = remote */
603 net->xfrm.policy_bydst[dir].dbits4 = lbits4;
604 net->xfrm.policy_bydst[dir].sbits4 = rbits4;
605 net->xfrm.policy_bydst[dir].dbits6 = lbits6;
606 net->xfrm.policy_bydst[dir].sbits6 = rbits6;
607 }
608 }
609
610 /* re-insert all policies by order of creation */
611 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
612 if (policy->walk.dead ||
613 xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
614 /* skip socket policies */
615 continue;
616 }
617 newpos = NULL;
618 chain = policy_hash_bysel(net, &policy->selector,
619 policy->family,
620 xfrm_policy_id2dir(policy->index));
621 hlist_for_each_entry(pol, chain, bydst) {
622 if (policy->priority >= pol->priority)
623 newpos = &pol->bydst;
624 else
625 break;
626 }
627 if (newpos)
628 hlist_add_behind(&policy->bydst, newpos);
629 else
630 hlist_add_head(&policy->bydst, chain);
631 }
632
633 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
634
635 mutex_unlock(&hash_resize_mutex);
636}
637
638void xfrm_policy_hash_rebuild(struct net *net)
639{
640 schedule_work(&net->xfrm.policy_hthresh.work);
641}
642EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
643
644/* Generate new index... KAME seems to generate them ordered by cost
645 * of an absolute inpredictability of ordering of rules. This will not pass. */
646static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
647{
648 static u32 idx_generator;
649
650 for (;;) {
651 struct hlist_head *list;
652 struct xfrm_policy *p;
653 u32 idx;
654 int found;
655
656 if (!index) {
657 idx = (idx_generator | dir);
658 idx_generator += 8;
659 } else {
660 idx = index;
661 index = 0;
662 }
663
664 if (idx == 0)
665 idx = 8;
666 list = net->xfrm.policy_byidx + idx_hash(net, idx);
667 found = 0;
668 hlist_for_each_entry(p, list, byidx) {
669 if (p->index == idx) {
670 found = 1;
671 break;
672 }
673 }
674 if (!found)
675 return idx;
676 }
677}
678
679static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
680{
681 u32 *p1 = (u32 *) s1;
682 u32 *p2 = (u32 *) s2;
683 int len = sizeof(struct xfrm_selector) / sizeof(u32);
684 int i;
685
686 for (i = 0; i < len; i++) {
687 if (p1[i] != p2[i])
688 return 1;
689 }
690
691 return 0;
692}
693
694static void xfrm_policy_requeue(struct xfrm_policy *old,
695 struct xfrm_policy *new)
696{
697 struct xfrm_policy_queue *pq = &old->polq;
698 struct sk_buff_head list;
699
700 if (skb_queue_empty(&pq->hold_queue))
701 return;
702
703 __skb_queue_head_init(&list);
704
705 spin_lock_bh(&pq->hold_queue.lock);
706 skb_queue_splice_init(&pq->hold_queue, &list);
707 if (del_timer(&pq->hold_timer))
708 xfrm_pol_put(old);
709 spin_unlock_bh(&pq->hold_queue.lock);
710
711 pq = &new->polq;
712
713 spin_lock_bh(&pq->hold_queue.lock);
714 skb_queue_splice(&list, &pq->hold_queue);
715 pq->timeout = XFRM_QUEUE_TMO_MIN;
716 if (!mod_timer(&pq->hold_timer, jiffies))
717 xfrm_pol_hold(new);
718 spin_unlock_bh(&pq->hold_queue.lock);
719}
720
721static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
722 struct xfrm_policy *pol)
723{
724 u32 mark = policy->mark.v & policy->mark.m;
725
726 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
727 return true;
728
729 if ((mark & pol->mark.m) == pol->mark.v &&
730 policy->priority == pol->priority)
731 return true;
732
733 return false;
734}
735
736int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
737{
738 struct net *net = xp_net(policy);
739 struct xfrm_policy *pol;
740 struct xfrm_policy *delpol;
741 struct hlist_head *chain;
742 struct hlist_node *newpos;
743
744 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
745 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
746 delpol = NULL;
747 newpos = NULL;
748 hlist_for_each_entry(pol, chain, bydst) {
749 if (pol->type == policy->type &&
750 !selector_cmp(&pol->selector, &policy->selector) &&
751 xfrm_policy_mark_match(policy, pol) &&
752 xfrm_sec_ctx_match(pol->security, policy->security) &&
753 !WARN_ON(delpol)) {
754 if (excl) {
755 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
756 return -EEXIST;
757 }
758 delpol = pol;
759 if (policy->priority > pol->priority)
760 continue;
761 } else if (policy->priority >= pol->priority) {
762 newpos = &pol->bydst;
763 continue;
764 }
765 if (delpol)
766 break;
767 }
768 if (newpos)
769 hlist_add_behind(&policy->bydst, newpos);
770 else
771 hlist_add_head(&policy->bydst, chain);
772 __xfrm_policy_link(policy, dir);
773
774 /* After previous checking, family can either be AF_INET or AF_INET6 */
775 if (policy->family == AF_INET)
776 rt_genid_bump_ipv4(net);
777 else
778 rt_genid_bump_ipv6(net);
779
780 if (delpol) {
781 xfrm_policy_requeue(delpol, policy);
782 __xfrm_policy_unlink(delpol, dir);
783 }
784 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
785 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
786 policy->curlft.add_time = get_seconds();
787 policy->curlft.use_time = 0;
788 if (!mod_timer(&policy->timer, jiffies + HZ))
789 xfrm_pol_hold(policy);
790 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
791
792 if (delpol)
793 xfrm_policy_kill(delpol);
794 else if (xfrm_bydst_should_resize(net, dir, NULL))
795 schedule_work(&net->xfrm.policy_hash_work);
796
797 return 0;
798}
799EXPORT_SYMBOL(xfrm_policy_insert);
800
801struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
802 int dir, struct xfrm_selector *sel,
803 struct xfrm_sec_ctx *ctx, int delete,
804 int *err)
805{
806 struct xfrm_policy *pol, *ret;
807 struct hlist_head *chain;
808
809 *err = 0;
810 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
811 chain = policy_hash_bysel(net, sel, sel->family, dir);
812 ret = NULL;
813 hlist_for_each_entry(pol, chain, bydst) {
814 if (pol->type == type &&
815 (mark & pol->mark.m) == pol->mark.v &&
816 !selector_cmp(sel, &pol->selector) &&
817 xfrm_sec_ctx_match(ctx, pol->security)) {
818 xfrm_pol_hold(pol);
819 if (delete) {
820 *err = security_xfrm_policy_delete(
821 pol->security);
822 if (*err) {
823 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
824 return pol;
825 }
826 __xfrm_policy_unlink(pol, dir);
827 }
828 ret = pol;
829 break;
830 }
831 }
832 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
833
834 if (ret && delete)
835 xfrm_policy_kill(ret);
836 return ret;
837}
838EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
839
840struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
841 int dir, u32 id, int delete, int *err)
842{
843 struct xfrm_policy *pol, *ret;
844 struct hlist_head *chain;
845
846 *err = -ENOENT;
847 if (xfrm_policy_id2dir(id) != dir)
848 return NULL;
849
850 *err = 0;
851 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
852 chain = net->xfrm.policy_byidx + idx_hash(net, id);
853 ret = NULL;
854 hlist_for_each_entry(pol, chain, byidx) {
855 if (pol->type == type && pol->index == id &&
856 (mark & pol->mark.m) == pol->mark.v) {
857 xfrm_pol_hold(pol);
858 if (delete) {
859 *err = security_xfrm_policy_delete(
860 pol->security);
861 if (*err) {
862 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
863 return pol;
864 }
865 __xfrm_policy_unlink(pol, dir);
866 }
867 ret = pol;
868 break;
869 }
870 }
871 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
872
873 if (ret && delete)
874 xfrm_policy_kill(ret);
875 return ret;
876}
877EXPORT_SYMBOL(xfrm_policy_byid);
878
879#ifdef CONFIG_SECURITY_NETWORK_XFRM
880static inline int
881xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
882{
883 int dir, err = 0;
884
885 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
886 struct xfrm_policy *pol;
887 int i;
888
889 hlist_for_each_entry(pol,
890 &net->xfrm.policy_inexact[dir], bydst) {
891 if (pol->type != type)
892 continue;
893 err = security_xfrm_policy_delete(pol->security);
894 if (err) {
895 xfrm_audit_policy_delete(pol, 0, task_valid);
896 return err;
897 }
898 }
899 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
900 hlist_for_each_entry(pol,
901 net->xfrm.policy_bydst[dir].table + i,
902 bydst) {
903 if (pol->type != type)
904 continue;
905 err = security_xfrm_policy_delete(
906 pol->security);
907 if (err) {
908 xfrm_audit_policy_delete(pol, 0,
909 task_valid);
910 return err;
911 }
912 }
913 }
914 }
915 return err;
916}
917#else
918static inline int
919xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
920{
921 return 0;
922}
923#endif
924
925int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
926{
927 int dir, err = 0, cnt = 0;
928
929 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
930
931 err = xfrm_policy_flush_secctx_check(net, type, task_valid);
932 if (err)
933 goto out;
934
935 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
936 struct xfrm_policy *pol;
937 int i;
938
939 again1:
940 hlist_for_each_entry(pol,
941 &net->xfrm.policy_inexact[dir], bydst) {
942 if (pol->type != type)
943 continue;
944 __xfrm_policy_unlink(pol, dir);
945 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
946 cnt++;
947
948 xfrm_audit_policy_delete(pol, 1, task_valid);
949
950 xfrm_policy_kill(pol);
951
952 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
953 goto again1;
954 }
955
956 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
957 again2:
958 hlist_for_each_entry(pol,
959 net->xfrm.policy_bydst[dir].table + i,
960 bydst) {
961 if (pol->type != type)
962 continue;
963 __xfrm_policy_unlink(pol, dir);
964 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
965 cnt++;
966
967 xfrm_audit_policy_delete(pol, 1, task_valid);
968 xfrm_policy_kill(pol);
969
970 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
971 goto again2;
972 }
973 }
974
975 }
976 if (!cnt)
977 err = -ESRCH;
978out:
979 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
980 return err;
981}
982EXPORT_SYMBOL(xfrm_policy_flush);
983
984int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
985 int (*func)(struct xfrm_policy *, int, int, void*),
986 void *data)
987{
988 struct xfrm_policy *pol;
989 struct xfrm_policy_walk_entry *x;
990 int error = 0;
991
992 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
993 walk->type != XFRM_POLICY_TYPE_ANY)
994 return -EINVAL;
995
996 if (list_empty(&walk->walk.all) && walk->seq != 0)
997 return 0;
998
999 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1000 if (list_empty(&walk->walk.all))
1001 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1002 else
1003 x = list_first_entry(&walk->walk.all,
1004 struct xfrm_policy_walk_entry, all);
1005
1006 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1007 if (x->dead)
1008 continue;
1009 pol = container_of(x, struct xfrm_policy, walk);
1010 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1011 walk->type != pol->type)
1012 continue;
1013 error = func(pol, xfrm_policy_id2dir(pol->index),
1014 walk->seq, data);
1015 if (error) {
1016 list_move_tail(&walk->walk.all, &x->all);
1017 goto out;
1018 }
1019 walk->seq++;
1020 }
1021 if (walk->seq == 0) {
1022 error = -ENOENT;
1023 goto out;
1024 }
1025 list_del_init(&walk->walk.all);
1026out:
1027 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1028 return error;
1029}
1030EXPORT_SYMBOL(xfrm_policy_walk);
1031
1032void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1033{
1034 INIT_LIST_HEAD(&walk->walk.all);
1035 walk->walk.dead = 1;
1036 walk->type = type;
1037 walk->seq = 0;
1038}
1039EXPORT_SYMBOL(xfrm_policy_walk_init);
1040
1041void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1042{
1043 if (list_empty(&walk->walk.all))
1044 return;
1045
1046 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1047 list_del(&walk->walk.all);
1048 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1049}
1050EXPORT_SYMBOL(xfrm_policy_walk_done);
1051
1052/*
1053 * Find policy to apply to this flow.
1054 *
1055 * Returns 0 if policy found, else an -errno.
1056 */
1057static int xfrm_policy_match(const struct xfrm_policy *pol,
1058 const struct flowi *fl,
1059 u8 type, u16 family, int dir)
1060{
1061 const struct xfrm_selector *sel = &pol->selector;
1062 int ret = -ESRCH;
1063 bool match;
1064
1065 if (pol->family != family ||
1066 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1067 pol->type != type)
1068 return ret;
1069
1070 match = xfrm_selector_match(sel, fl, family);
1071 if (match)
1072 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1073 dir);
1074
1075 return ret;
1076}
1077
1078static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1079 const struct flowi *fl,
1080 u16 family, u8 dir)
1081{
1082 int err;
1083 struct xfrm_policy *pol, *ret;
1084 const xfrm_address_t *daddr, *saddr;
1085 struct hlist_head *chain;
1086 unsigned int sequence;
1087 u32 priority;
1088
1089 daddr = xfrm_flowi_daddr(fl, family);
1090 saddr = xfrm_flowi_saddr(fl, family);
1091 if (unlikely(!daddr || !saddr))
1092 return NULL;
1093
1094 rcu_read_lock();
1095 retry:
1096 do {
1097 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1098 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1099 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1100
1101 priority = ~0U;
1102 ret = NULL;
1103 hlist_for_each_entry_rcu(pol, chain, bydst) {
1104 err = xfrm_policy_match(pol, fl, type, family, dir);
1105 if (err) {
1106 if (err == -ESRCH)
1107 continue;
1108 else {
1109 ret = ERR_PTR(err);
1110 goto fail;
1111 }
1112 } else {
1113 ret = pol;
1114 priority = ret->priority;
1115 break;
1116 }
1117 }
1118 chain = &net->xfrm.policy_inexact[dir];
1119 hlist_for_each_entry_rcu(pol, chain, bydst) {
1120 if ((pol->priority >= priority) && ret)
1121 break;
1122
1123 err = xfrm_policy_match(pol, fl, type, family, dir);
1124 if (err) {
1125 if (err == -ESRCH)
1126 continue;
1127 else {
1128 ret = ERR_PTR(err);
1129 goto fail;
1130 }
1131 } else {
1132 ret = pol;
1133 break;
1134 }
1135 }
1136
1137 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1138 goto retry;
1139
1140 if (ret && !xfrm_pol_hold_rcu(ret))
1141 goto retry;
1142fail:
1143 rcu_read_unlock();
1144
1145 return ret;
1146}
1147
1148static struct xfrm_policy *
1149xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1150{
1151#ifdef CONFIG_XFRM_SUB_POLICY
1152 struct xfrm_policy *pol;
1153
1154 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1155 if (pol != NULL)
1156 return pol;
1157#endif
1158 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1159}
1160
1161static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1162 const struct flowi *fl, u16 family)
1163{
1164 struct xfrm_policy *pol;
1165
1166 rcu_read_lock();
1167 again:
1168 pol = rcu_dereference(sk->sk_policy[dir]);
1169 if (pol != NULL) {
1170 bool match;
1171 int err = 0;
1172
1173 if (pol->family != family) {
1174 pol = NULL;
1175 goto out;
1176 }
1177
1178 match = xfrm_selector_match(&pol->selector, fl, family);
1179 if (match) {
1180 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1181 pol = NULL;
1182 goto out;
1183 }
1184 err = security_xfrm_policy_lookup(pol->security,
1185 fl->flowi_secid,
1186 dir);
1187 if (!err) {
1188 if (!xfrm_pol_hold_rcu(pol))
1189 goto again;
1190 } else if (err == -ESRCH) {
1191 pol = NULL;
1192 } else {
1193 pol = ERR_PTR(err);
1194 }
1195 } else
1196 pol = NULL;
1197 }
1198out:
1199 rcu_read_unlock();
1200 return pol;
1201}
1202
1203static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1204{
1205 struct net *net = xp_net(pol);
1206
1207 list_add(&pol->walk.all, &net->xfrm.policy_all);
1208 net->xfrm.policy_count[dir]++;
1209 xfrm_pol_hold(pol);
1210}
1211
1212static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1213 int dir)
1214{
1215 struct net *net = xp_net(pol);
1216
1217 if (list_empty(&pol->walk.all))
1218 return NULL;
1219
1220 /* Socket policies are not hashed. */
1221 if (!hlist_unhashed(&pol->bydst)) {
1222 hlist_del_rcu(&pol->bydst);
1223 hlist_del(&pol->byidx);
1224 }
1225
1226 list_del_init(&pol->walk.all);
1227 net->xfrm.policy_count[dir]--;
1228
1229 return pol;
1230}
1231
1232static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1233{
1234 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1235}
1236
1237static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1238{
1239 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1240}
1241
1242int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1243{
1244 struct net *net = xp_net(pol);
1245
1246 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1247 pol = __xfrm_policy_unlink(pol, dir);
1248 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1249 if (pol) {
1250 xfrm_policy_kill(pol);
1251 return 0;
1252 }
1253 return -ENOENT;
1254}
1255EXPORT_SYMBOL(xfrm_policy_delete);
1256
1257int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1258{
1259 struct net *net = sock_net(sk);
1260 struct xfrm_policy *old_pol;
1261
1262#ifdef CONFIG_XFRM_SUB_POLICY
1263 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1264 return -EINVAL;
1265#endif
1266
1267 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1268 old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1269 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1270 if (pol) {
1271 pol->curlft.add_time = get_seconds();
1272 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1273 xfrm_sk_policy_link(pol, dir);
1274 }
1275 rcu_assign_pointer(sk->sk_policy[dir], pol);
1276 if (old_pol) {
1277 if (pol)
1278 xfrm_policy_requeue(old_pol, pol);
1279
1280 /* Unlinking succeeds always. This is the only function
1281 * allowed to delete or replace socket policy.
1282 */
1283 xfrm_sk_policy_unlink(old_pol, dir);
1284 }
1285 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1286
1287 if (old_pol) {
1288 xfrm_policy_kill(old_pol);
1289 }
1290 return 0;
1291}
1292
1293static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1294{
1295 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1296 struct net *net = xp_net(old);
1297
1298 if (newp) {
1299 newp->selector = old->selector;
1300 if (security_xfrm_policy_clone(old->security,
1301 &newp->security)) {
1302 kfree(newp);
1303 return NULL; /* ENOMEM */
1304 }
1305 newp->lft = old->lft;
1306 newp->curlft = old->curlft;
1307 newp->mark = old->mark;
1308 newp->action = old->action;
1309 newp->flags = old->flags;
1310 newp->xfrm_nr = old->xfrm_nr;
1311 newp->index = old->index;
1312 newp->type = old->type;
1313 newp->family = old->family;
1314 memcpy(newp->xfrm_vec, old->xfrm_vec,
1315 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1316 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1317 xfrm_sk_policy_link(newp, dir);
1318 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1319 xfrm_pol_put(newp);
1320 }
1321 return newp;
1322}
1323
1324int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1325{
1326 const struct xfrm_policy *p;
1327 struct xfrm_policy *np;
1328 int i, ret = 0;
1329
1330 rcu_read_lock();
1331 for (i = 0; i < 2; i++) {
1332 p = rcu_dereference(osk->sk_policy[i]);
1333 if (p) {
1334 np = clone_policy(p, i);
1335 if (unlikely(!np)) {
1336 ret = -ENOMEM;
1337 break;
1338 }
1339 rcu_assign_pointer(sk->sk_policy[i], np);
1340 }
1341 }
1342 rcu_read_unlock();
1343 return ret;
1344}
1345
1346static int
1347xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1348 xfrm_address_t *remote, unsigned short family, u32 mark)
1349{
1350 int err;
1351 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1352
1353 if (unlikely(afinfo == NULL))
1354 return -EINVAL;
1355 err = afinfo->get_saddr(net, oif, local, remote, mark);
1356 rcu_read_unlock();
1357 return err;
1358}
1359
1360/* Resolve list of templates for the flow, given policy. */
1361
1362static int
1363xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1364 struct xfrm_state **xfrm, unsigned short family)
1365{
1366 struct net *net = xp_net(policy);
1367 int nx;
1368 int i, error;
1369 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1370 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1371 xfrm_address_t tmp;
1372
1373 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1374 struct xfrm_state *x;
1375 xfrm_address_t *remote = daddr;
1376 xfrm_address_t *local = saddr;
1377 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1378
1379 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1380 tmpl->mode == XFRM_MODE_BEET) {
1381 remote = &tmpl->id.daddr;
1382 local = &tmpl->saddr;
1383 if (xfrm_addr_any(local, tmpl->encap_family)) {
1384 error = xfrm_get_saddr(net, fl->flowi_oif,
1385 &tmp, remote,
1386 tmpl->encap_family, 0);
1387 if (error)
1388 goto fail;
1389 local = &tmp;
1390 }
1391 }
1392
1393 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1394
1395 if (x && x->km.state == XFRM_STATE_VALID) {
1396 xfrm[nx++] = x;
1397 daddr = remote;
1398 saddr = local;
1399 continue;
1400 }
1401 if (x) {
1402 error = (x->km.state == XFRM_STATE_ERROR ?
1403 -EINVAL : -EAGAIN);
1404 xfrm_state_put(x);
1405 } else if (error == -ESRCH) {
1406 error = -EAGAIN;
1407 }
1408
1409 if (!tmpl->optional)
1410 goto fail;
1411 }
1412 return nx;
1413
1414fail:
1415 for (nx--; nx >= 0; nx--)
1416 xfrm_state_put(xfrm[nx]);
1417 return error;
1418}
1419
1420static int
1421xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1422 struct xfrm_state **xfrm, unsigned short family)
1423{
1424 struct xfrm_state *tp[XFRM_MAX_DEPTH];
1425 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1426 int cnx = 0;
1427 int error;
1428 int ret;
1429 int i;
1430
1431 for (i = 0; i < npols; i++) {
1432 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1433 error = -ENOBUFS;
1434 goto fail;
1435 }
1436
1437 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1438 if (ret < 0) {
1439 error = ret;
1440 goto fail;
1441 } else
1442 cnx += ret;
1443 }
1444
1445 /* found states are sorted for outbound processing */
1446 if (npols > 1)
1447 xfrm_state_sort(xfrm, tpp, cnx, family);
1448
1449 return cnx;
1450
1451 fail:
1452 for (cnx--; cnx >= 0; cnx--)
1453 xfrm_state_put(tpp[cnx]);
1454 return error;
1455
1456}
1457
1458static int xfrm_get_tos(const struct flowi *fl, int family)
1459{
1460 const struct xfrm_policy_afinfo *afinfo;
1461 int tos;
1462
1463 afinfo = xfrm_policy_get_afinfo(family);
1464 if (!afinfo)
1465 return 0;
1466
1467 tos = afinfo->get_tos(fl);
1468
1469 rcu_read_unlock();
1470
1471 return tos;
1472}
1473
1474static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1475{
1476 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1477 struct dst_ops *dst_ops;
1478 struct xfrm_dst *xdst;
1479
1480 if (!afinfo)
1481 return ERR_PTR(-EINVAL);
1482
1483 switch (family) {
1484 case AF_INET:
1485 dst_ops = &net->xfrm.xfrm4_dst_ops;
1486 break;
1487#if IS_ENABLED(CONFIG_IPV6)
1488 case AF_INET6:
1489 dst_ops = &net->xfrm.xfrm6_dst_ops;
1490 break;
1491#endif
1492 default:
1493 BUG();
1494 }
1495 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
1496
1497 if (likely(xdst)) {
1498 struct dst_entry *dst = &xdst->u.dst;
1499
1500 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1501 } else
1502 xdst = ERR_PTR(-ENOBUFS);
1503
1504 rcu_read_unlock();
1505
1506 return xdst;
1507}
1508
1509static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1510 int nfheader_len)
1511{
1512 const struct xfrm_policy_afinfo *afinfo =
1513 xfrm_policy_get_afinfo(dst->ops->family);
1514 int err;
1515
1516 if (!afinfo)
1517 return -EINVAL;
1518
1519 err = afinfo->init_path(path, dst, nfheader_len);
1520
1521 rcu_read_unlock();
1522
1523 return err;
1524}
1525
1526static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1527 const struct flowi *fl)
1528{
1529 const struct xfrm_policy_afinfo *afinfo =
1530 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1531 int err;
1532
1533 if (!afinfo)
1534 return -EINVAL;
1535
1536 err = afinfo->fill_dst(xdst, dev, fl);
1537
1538 rcu_read_unlock();
1539
1540 return err;
1541}
1542
1543
1544/* Allocate chain of dst_entry's, attach known xfrm's, calculate
1545 * all the metrics... Shortly, bundle a bundle.
1546 */
1547
1548static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1549 struct xfrm_state **xfrm,
1550 struct xfrm_dst **bundle,
1551 int nx,
1552 const struct flowi *fl,
1553 struct dst_entry *dst)
1554{
1555 struct net *net = xp_net(policy);
1556 unsigned long now = jiffies;
1557 struct net_device *dev;
1558 struct xfrm_mode *inner_mode;
1559 struct xfrm_dst *xdst_prev = NULL;
1560 struct xfrm_dst *xdst0 = NULL;
1561 int i = 0;
1562 int err;
1563 int header_len = 0;
1564 int nfheader_len = 0;
1565 int trailer_len = 0;
1566 int tos;
1567 int family = policy->selector.family;
1568 xfrm_address_t saddr, daddr;
1569
1570 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1571
1572 tos = xfrm_get_tos(fl, family);
1573
1574 dst_hold(dst);
1575
1576 for (; i < nx; i++) {
1577 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1578 struct dst_entry *dst1 = &xdst->u.dst;
1579
1580 err = PTR_ERR(xdst);
1581 if (IS_ERR(xdst)) {
1582 dst_release(dst);
1583 goto put_states;
1584 }
1585
1586 bundle[i] = xdst;
1587 if (!xdst_prev)
1588 xdst0 = xdst;
1589 else
1590 /* Ref count is taken during xfrm_alloc_dst()
1591 * No need to do dst_clone() on dst1
1592 */
1593 xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
1594
1595 if (xfrm[i]->sel.family == AF_UNSPEC) {
1596 inner_mode = xfrm_ip2inner_mode(xfrm[i],
1597 xfrm_af2proto(family));
1598 if (!inner_mode) {
1599 err = -EAFNOSUPPORT;
1600 dst_release(dst);
1601 goto put_states;
1602 }
1603 } else
1604 inner_mode = xfrm[i]->inner_mode;
1605
1606 xdst->route = dst;
1607 dst_copy_metrics(dst1, dst);
1608
1609 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1610 family = xfrm[i]->props.family;
1611 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1612 &saddr, &daddr, family,
1613 xfrm[i]->props.output_mark);
1614 err = PTR_ERR(dst);
1615 if (IS_ERR(dst))
1616 goto put_states;
1617 } else
1618 dst_hold(dst);
1619
1620 dst1->xfrm = xfrm[i];
1621 xdst->xfrm_genid = xfrm[i]->genid;
1622
1623 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1624 dst1->flags |= DST_HOST;
1625 dst1->lastuse = now;
1626
1627 dst1->input = dst_discard;
1628 dst1->output = inner_mode->afinfo->output;
1629
1630 xdst_prev = xdst;
1631
1632 header_len += xfrm[i]->props.header_len;
1633 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1634 nfheader_len += xfrm[i]->props.header_len;
1635 trailer_len += xfrm[i]->props.trailer_len;
1636 }
1637
1638 xfrm_dst_set_child(xdst_prev, dst);
1639 xdst0->path = dst;
1640
1641 err = -ENODEV;
1642 dev = dst->dev;
1643 if (!dev)
1644 goto free_dst;
1645
1646 xfrm_init_path(xdst0, dst, nfheader_len);
1647 xfrm_init_pmtu(bundle, nx);
1648
1649 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
1650 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
1651 err = xfrm_fill_dst(xdst_prev, dev, fl);
1652 if (err)
1653 goto free_dst;
1654
1655 xdst_prev->u.dst.header_len = header_len;
1656 xdst_prev->u.dst.trailer_len = trailer_len;
1657 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
1658 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
1659 }
1660
1661 return &xdst0->u.dst;
1662
1663put_states:
1664 for (; i < nx; i++)
1665 xfrm_state_put(xfrm[i]);
1666free_dst:
1667 if (xdst0)
1668 dst_release_immediate(&xdst0->u.dst);
1669
1670 return ERR_PTR(err);
1671}
1672
1673static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1674 struct xfrm_policy **pols,
1675 int *num_pols, int *num_xfrms)
1676{
1677 int i;
1678
1679 if (*num_pols == 0 || !pols[0]) {
1680 *num_pols = 0;
1681 *num_xfrms = 0;
1682 return 0;
1683 }
1684 if (IS_ERR(pols[0]))
1685 return PTR_ERR(pols[0]);
1686
1687 *num_xfrms = pols[0]->xfrm_nr;
1688
1689#ifdef CONFIG_XFRM_SUB_POLICY
1690 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1691 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1692 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1693 XFRM_POLICY_TYPE_MAIN,
1694 fl, family,
1695 XFRM_POLICY_OUT);
1696 if (pols[1]) {
1697 if (IS_ERR(pols[1])) {
1698 xfrm_pols_put(pols, *num_pols);
1699 return PTR_ERR(pols[1]);
1700 }
1701 (*num_pols)++;
1702 (*num_xfrms) += pols[1]->xfrm_nr;
1703 }
1704 }
1705#endif
1706 for (i = 0; i < *num_pols; i++) {
1707 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1708 *num_xfrms = -1;
1709 break;
1710 }
1711 }
1712
1713 return 0;
1714
1715}
1716
1717static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old)
1718{
1719 this_cpu_write(xfrm_last_dst, xdst);
1720 if (old)
1721 dst_release(&old->u.dst);
1722}
1723
1724static void __xfrm_pcpu_work_fn(void)
1725{
1726 struct xfrm_dst *old;
1727
1728 old = this_cpu_read(xfrm_last_dst);
1729 if (old && !xfrm_bundle_ok(old))
1730 xfrm_last_dst_update(NULL, old);
1731}
1732
1733static void xfrm_pcpu_work_fn(struct work_struct *work)
1734{
1735 local_bh_disable();
1736 rcu_read_lock();
1737 __xfrm_pcpu_work_fn();
1738 rcu_read_unlock();
1739 local_bh_enable();
1740}
1741
1742void xfrm_policy_cache_flush(void)
1743{
1744 struct xfrm_dst *old;
1745 bool found = false;
1746 int cpu;
1747
1748 might_sleep();
1749
1750 local_bh_disable();
1751 rcu_read_lock();
1752 for_each_possible_cpu(cpu) {
1753 old = per_cpu(xfrm_last_dst, cpu);
1754 if (old && !xfrm_bundle_ok(old)) {
1755 if (smp_processor_id() == cpu) {
1756 __xfrm_pcpu_work_fn();
1757 continue;
1758 }
1759 found = true;
1760 break;
1761 }
1762 }
1763
1764 rcu_read_unlock();
1765 local_bh_enable();
1766
1767 if (!found)
1768 return;
1769
1770 get_online_cpus();
1771
1772 for_each_possible_cpu(cpu) {
1773 bool bundle_release;
1774
1775 rcu_read_lock();
1776 old = per_cpu(xfrm_last_dst, cpu);
1777 bundle_release = old && !xfrm_bundle_ok(old);
1778 rcu_read_unlock();
1779
1780 if (!bundle_release)
1781 continue;
1782
1783 if (cpu_online(cpu)) {
1784 schedule_work_on(cpu, &xfrm_pcpu_work[cpu]);
1785 continue;
1786 }
1787
1788 rcu_read_lock();
1789 old = per_cpu(xfrm_last_dst, cpu);
1790 if (old && !xfrm_bundle_ok(old)) {
1791 per_cpu(xfrm_last_dst, cpu) = NULL;
1792 dst_release(&old->u.dst);
1793 }
1794 rcu_read_unlock();
1795 }
1796
1797 put_online_cpus();
1798}
1799
1800static bool xfrm_xdst_can_reuse(struct xfrm_dst *xdst,
1801 struct xfrm_state * const xfrm[],
1802 int num)
1803{
1804 const struct dst_entry *dst = &xdst->u.dst;
1805 int i;
1806
1807 if (xdst->num_xfrms != num)
1808 return false;
1809
1810 for (i = 0; i < num; i++) {
1811 if (!dst || dst->xfrm != xfrm[i])
1812 return false;
1813 dst = xfrm_dst_child(dst);
1814 }
1815
1816 return xfrm_bundle_ok(xdst);
1817}
1818
1819static struct xfrm_dst *
1820xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1821 const struct flowi *fl, u16 family,
1822 struct dst_entry *dst_orig)
1823{
1824 struct net *net = xp_net(pols[0]);
1825 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1826 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
1827 struct xfrm_dst *xdst, *old;
1828 struct dst_entry *dst;
1829 int err;
1830
1831 /* Try to instantiate a bundle */
1832 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1833 if (err <= 0) {
1834 if (err != 0 && err != -EAGAIN)
1835 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1836 return ERR_PTR(err);
1837 }
1838
1839 xdst = this_cpu_read(xfrm_last_dst);
1840 if (xdst &&
1841 xdst->u.dst.dev == dst_orig->dev &&
1842 xdst->num_pols == num_pols &&
1843 memcmp(xdst->pols, pols,
1844 sizeof(struct xfrm_policy *) * num_pols) == 0 &&
1845 xfrm_xdst_can_reuse(xdst, xfrm, err)) {
1846 dst_hold(&xdst->u.dst);
1847 xfrm_pols_put(pols, num_pols);
1848 while (err > 0)
1849 xfrm_state_put(xfrm[--err]);
1850 return xdst;
1851 }
1852
1853 old = xdst;
1854
1855 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
1856 if (IS_ERR(dst)) {
1857 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1858 return ERR_CAST(dst);
1859 }
1860
1861 xdst = (struct xfrm_dst *)dst;
1862 xdst->num_xfrms = err;
1863 xdst->num_pols = num_pols;
1864 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1865 xdst->policy_genid = atomic_read(&pols[0]->genid);
1866
1867 atomic_set(&xdst->u.dst.__refcnt, 2);
1868 xfrm_last_dst_update(xdst, old);
1869
1870 return xdst;
1871}
1872
1873static void xfrm_policy_queue_process(struct timer_list *t)
1874{
1875 struct sk_buff *skb;
1876 struct sock *sk;
1877 struct dst_entry *dst;
1878 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
1879 struct net *net = xp_net(pol);
1880 struct xfrm_policy_queue *pq = &pol->polq;
1881 struct flowi fl;
1882 struct sk_buff_head list;
1883
1884 spin_lock(&pq->hold_queue.lock);
1885 skb = skb_peek(&pq->hold_queue);
1886 if (!skb) {
1887 spin_unlock(&pq->hold_queue.lock);
1888 goto out;
1889 }
1890 dst = skb_dst(skb);
1891 sk = skb->sk;
1892 xfrm_decode_session(skb, &fl, dst->ops->family);
1893 spin_unlock(&pq->hold_queue.lock);
1894
1895 dst_hold(xfrm_dst_path(dst));
1896 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
1897 if (IS_ERR(dst))
1898 goto purge_queue;
1899
1900 if (dst->flags & DST_XFRM_QUEUE) {
1901 dst_release(dst);
1902
1903 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1904 goto purge_queue;
1905
1906 pq->timeout = pq->timeout << 1;
1907 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1908 xfrm_pol_hold(pol);
1909 goto out;
1910 }
1911
1912 dst_release(dst);
1913
1914 __skb_queue_head_init(&list);
1915
1916 spin_lock(&pq->hold_queue.lock);
1917 pq->timeout = 0;
1918 skb_queue_splice_init(&pq->hold_queue, &list);
1919 spin_unlock(&pq->hold_queue.lock);
1920
1921 while (!skb_queue_empty(&list)) {
1922 skb = __skb_dequeue(&list);
1923
1924 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1925 dst_hold(xfrm_dst_path(skb_dst(skb)));
1926 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
1927 if (IS_ERR(dst)) {
1928 kfree_skb(skb);
1929 continue;
1930 }
1931
1932 nf_reset(skb);
1933 skb_dst_drop(skb);
1934 skb_dst_set(skb, dst);
1935
1936 dst_output(net, skb->sk, skb);
1937 }
1938
1939out:
1940 xfrm_pol_put(pol);
1941 return;
1942
1943purge_queue:
1944 pq->timeout = 0;
1945 skb_queue_purge(&pq->hold_queue);
1946 xfrm_pol_put(pol);
1947}
1948
1949static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1950{
1951 unsigned long sched_next;
1952 struct dst_entry *dst = skb_dst(skb);
1953 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1954 struct xfrm_policy *pol = xdst->pols[0];
1955 struct xfrm_policy_queue *pq = &pol->polq;
1956
1957 if (unlikely(skb_fclone_busy(sk, skb))) {
1958 kfree_skb(skb);
1959 return 0;
1960 }
1961
1962 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1963 kfree_skb(skb);
1964 return -EAGAIN;
1965 }
1966
1967 skb_dst_force(skb);
1968
1969 spin_lock_bh(&pq->hold_queue.lock);
1970
1971 if (!pq->timeout)
1972 pq->timeout = XFRM_QUEUE_TMO_MIN;
1973
1974 sched_next = jiffies + pq->timeout;
1975
1976 if (del_timer(&pq->hold_timer)) {
1977 if (time_before(pq->hold_timer.expires, sched_next))
1978 sched_next = pq->hold_timer.expires;
1979 xfrm_pol_put(pol);
1980 }
1981
1982 __skb_queue_tail(&pq->hold_queue, skb);
1983 if (!mod_timer(&pq->hold_timer, sched_next))
1984 xfrm_pol_hold(pol);
1985
1986 spin_unlock_bh(&pq->hold_queue.lock);
1987
1988 return 0;
1989}
1990
1991static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1992 struct xfrm_flo *xflo,
1993 const struct flowi *fl,
1994 int num_xfrms,
1995 u16 family)
1996{
1997 int err;
1998 struct net_device *dev;
1999 struct dst_entry *dst;
2000 struct dst_entry *dst1;
2001 struct xfrm_dst *xdst;
2002
2003 xdst = xfrm_alloc_dst(net, family);
2004 if (IS_ERR(xdst))
2005 return xdst;
2006
2007 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2008 net->xfrm.sysctl_larval_drop ||
2009 num_xfrms <= 0)
2010 return xdst;
2011
2012 dst = xflo->dst_orig;
2013 dst1 = &xdst->u.dst;
2014 dst_hold(dst);
2015 xdst->route = dst;
2016
2017 dst_copy_metrics(dst1, dst);
2018
2019 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2020 dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2021 dst1->lastuse = jiffies;
2022
2023 dst1->input = dst_discard;
2024 dst1->output = xdst_queue_output;
2025
2026 dst_hold(dst);
2027 xfrm_dst_set_child(xdst, dst);
2028 xdst->path = dst;
2029
2030 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2031
2032 err = -ENODEV;
2033 dev = dst->dev;
2034 if (!dev)
2035 goto free_dst;
2036
2037 err = xfrm_fill_dst(xdst, dev, fl);
2038 if (err)
2039 goto free_dst;
2040
2041out:
2042 return xdst;
2043
2044free_dst:
2045 dst_release(dst1);
2046 xdst = ERR_PTR(err);
2047 goto out;
2048}
2049
2050static struct xfrm_dst *
2051xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo)
2052{
2053 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2054 int num_pols = 0, num_xfrms = 0, err;
2055 struct xfrm_dst *xdst;
2056
2057 /* Resolve policies to use if we couldn't get them from
2058 * previous cache entry */
2059 num_pols = 1;
2060 pols[0] = xfrm_policy_lookup(net, fl, family, dir);
2061 err = xfrm_expand_policies(fl, family, pols,
2062 &num_pols, &num_xfrms);
2063 if (err < 0)
2064 goto inc_error;
2065 if (num_pols == 0)
2066 return NULL;
2067 if (num_xfrms <= 0)
2068 goto make_dummy_bundle;
2069
2070 local_bh_disable();
2071 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2072 xflo->dst_orig);
2073 local_bh_enable();
2074
2075 if (IS_ERR(xdst)) {
2076 err = PTR_ERR(xdst);
2077 if (err != -EAGAIN)
2078 goto error;
2079 goto make_dummy_bundle;
2080 } else if (xdst == NULL) {
2081 num_xfrms = 0;
2082 goto make_dummy_bundle;
2083 }
2084
2085 return xdst;
2086
2087make_dummy_bundle:
2088 /* We found policies, but there's no bundles to instantiate:
2089 * either because the policy blocks, has no transformations or
2090 * we could not build template (no xfrm_states).*/
2091 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2092 if (IS_ERR(xdst)) {
2093 xfrm_pols_put(pols, num_pols);
2094 return ERR_CAST(xdst);
2095 }
2096 xdst->num_pols = num_pols;
2097 xdst->num_xfrms = num_xfrms;
2098 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2099
2100 return xdst;
2101
2102inc_error:
2103 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2104error:
2105 xfrm_pols_put(pols, num_pols);
2106 return ERR_PTR(err);
2107}
2108
2109static struct dst_entry *make_blackhole(struct net *net, u16 family,
2110 struct dst_entry *dst_orig)
2111{
2112 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2113 struct dst_entry *ret;
2114
2115 if (!afinfo) {
2116 dst_release(dst_orig);
2117 return ERR_PTR(-EINVAL);
2118 } else {
2119 ret = afinfo->blackhole_route(net, dst_orig);
2120 }
2121 rcu_read_unlock();
2122
2123 return ret;
2124}
2125
2126/* Main function: finds/creates a bundle for given flow.
2127 *
2128 * At the moment we eat a raw IP route. Mostly to speed up lookups
2129 * on interfaces with disabled IPsec.
2130 */
2131struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2132 const struct flowi *fl,
2133 const struct sock *sk, int flags)
2134{
2135 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2136 struct xfrm_dst *xdst;
2137 struct dst_entry *dst, *route;
2138 u16 family = dst_orig->ops->family;
2139 u8 dir = XFRM_POLICY_OUT;
2140 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2141
2142 dst = NULL;
2143 xdst = NULL;
2144 route = NULL;
2145
2146 sk = sk_const_to_full_sk(sk);
2147 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2148 num_pols = 1;
2149 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family);
2150 err = xfrm_expand_policies(fl, family, pols,
2151 &num_pols, &num_xfrms);
2152 if (err < 0)
2153 goto dropdst;
2154
2155 if (num_pols) {
2156 if (num_xfrms <= 0) {
2157 drop_pols = num_pols;
2158 goto no_transform;
2159 }
2160
2161 local_bh_disable();
2162 xdst = xfrm_resolve_and_create_bundle(
2163 pols, num_pols, fl,
2164 family, dst_orig);
2165 local_bh_enable();
2166
2167 if (IS_ERR(xdst)) {
2168 xfrm_pols_put(pols, num_pols);
2169 err = PTR_ERR(xdst);
2170 goto dropdst;
2171 } else if (xdst == NULL) {
2172 num_xfrms = 0;
2173 drop_pols = num_pols;
2174 goto no_transform;
2175 }
2176
2177 route = xdst->route;
2178 }
2179 }
2180
2181 if (xdst == NULL) {
2182 struct xfrm_flo xflo;
2183
2184 xflo.dst_orig = dst_orig;
2185 xflo.flags = flags;
2186
2187 /* To accelerate a bit... */
2188 if ((dst_orig->flags & DST_NOXFRM) ||
2189 !net->xfrm.policy_count[XFRM_POLICY_OUT])
2190 goto nopol;
2191
2192 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo);
2193 if (xdst == NULL)
2194 goto nopol;
2195 if (IS_ERR(xdst)) {
2196 err = PTR_ERR(xdst);
2197 goto dropdst;
2198 }
2199
2200 num_pols = xdst->num_pols;
2201 num_xfrms = xdst->num_xfrms;
2202 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2203 route = xdst->route;
2204 }
2205
2206 dst = &xdst->u.dst;
2207 if (route == NULL && num_xfrms > 0) {
2208 /* The only case when xfrm_bundle_lookup() returns a
2209 * bundle with null route, is when the template could
2210 * not be resolved. It means policies are there, but
2211 * bundle could not be created, since we don't yet
2212 * have the xfrm_state's. We need to wait for KM to
2213 * negotiate new SA's or bail out with error.*/
2214 if (net->xfrm.sysctl_larval_drop) {
2215 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2216 err = -EREMOTE;
2217 goto error;
2218 }
2219
2220 err = -EAGAIN;
2221
2222 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2223 goto error;
2224 }
2225
2226no_transform:
2227 if (num_pols == 0)
2228 goto nopol;
2229
2230 if ((flags & XFRM_LOOKUP_ICMP) &&
2231 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2232 err = -ENOENT;
2233 goto error;
2234 }
2235
2236 for (i = 0; i < num_pols; i++)
2237 pols[i]->curlft.use_time = get_seconds();
2238
2239 if (num_xfrms < 0) {
2240 /* Prohibit the flow */
2241 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2242 err = -EPERM;
2243 goto error;
2244 } else if (num_xfrms > 0) {
2245 /* Flow transformed */
2246 dst_release(dst_orig);
2247 } else {
2248 /* Flow passes untransformed */
2249 dst_release(dst);
2250 dst = dst_orig;
2251 }
2252ok:
2253 xfrm_pols_put(pols, drop_pols);
2254 if (dst && dst->xfrm &&
2255 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2256 dst->flags |= DST_XFRM_TUNNEL;
2257 return dst;
2258
2259nopol:
2260 if (!(flags & XFRM_LOOKUP_ICMP)) {
2261 dst = dst_orig;
2262 goto ok;
2263 }
2264 err = -ENOENT;
2265error:
2266 dst_release(dst);
2267dropdst:
2268 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2269 dst_release(dst_orig);
2270 xfrm_pols_put(pols, drop_pols);
2271 return ERR_PTR(err);
2272}
2273EXPORT_SYMBOL(xfrm_lookup);
2274
2275/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2276 * Otherwise we may send out blackholed packets.
2277 */
2278struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2279 const struct flowi *fl,
2280 const struct sock *sk, int flags)
2281{
2282 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2283 flags | XFRM_LOOKUP_QUEUE |
2284 XFRM_LOOKUP_KEEP_DST_REF);
2285
2286 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2287 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2288
2289 return dst;
2290}
2291EXPORT_SYMBOL(xfrm_lookup_route);
2292
2293static inline int
2294xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2295{
2296 struct xfrm_state *x;
2297
2298 if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2299 return 0;
2300 x = skb->sp->xvec[idx];
2301 if (!x->type->reject)
2302 return 0;
2303 return x->type->reject(x, skb, fl);
2304}
2305
2306/* When skb is transformed back to its "native" form, we have to
2307 * check policy restrictions. At the moment we make this in maximally
2308 * stupid way. Shame on me. :-) Of course, connected sockets must
2309 * have policy cached at them.
2310 */
2311
2312static inline int
2313xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2314 unsigned short family)
2315{
2316 if (xfrm_state_kern(x))
2317 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2318 return x->id.proto == tmpl->id.proto &&
2319 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2320 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2321 x->props.mode == tmpl->mode &&
2322 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2323 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2324 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2325 xfrm_state_addr_cmp(tmpl, x, family));
2326}
2327
2328/*
2329 * 0 or more than 0 is returned when validation is succeeded (either bypass
2330 * because of optional transport mode, or next index of the mathced secpath
2331 * state with the template.
2332 * -1 is returned when no matching template is found.
2333 * Otherwise "-2 - errored_index" is returned.
2334 */
2335static inline int
2336xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2337 unsigned short family)
2338{
2339 int idx = start;
2340
2341 if (tmpl->optional) {
2342 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2343 return start;
2344 } else
2345 start = -1;
2346 for (; idx < sp->len; idx++) {
2347 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2348 return ++idx;
2349 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2350 if (start == -1)
2351 start = -2-idx;
2352 break;
2353 }
2354 }
2355 return start;
2356}
2357
2358int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2359 unsigned int family, int reverse)
2360{
2361 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2362 int err;
2363
2364 if (unlikely(afinfo == NULL))
2365 return -EAFNOSUPPORT;
2366
2367 afinfo->decode_session(skb, fl, reverse);
2368 err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2369 rcu_read_unlock();
2370 return err;
2371}
2372EXPORT_SYMBOL(__xfrm_decode_session);
2373
2374static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2375{
2376 for (; k < sp->len; k++) {
2377 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2378 *idxp = k;
2379 return 1;
2380 }
2381 }
2382
2383 return 0;
2384}
2385
2386int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2387 unsigned short family)
2388{
2389 struct net *net = dev_net(skb->dev);
2390 struct xfrm_policy *pol;
2391 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2392 int npols = 0;
2393 int xfrm_nr;
2394 int pi;
2395 int reverse;
2396 struct flowi fl;
2397 int xerr_idx = -1;
2398
2399 reverse = dir & ~XFRM_POLICY_MASK;
2400 dir &= XFRM_POLICY_MASK;
2401
2402 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2403 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2404 return 0;
2405 }
2406
2407 nf_nat_decode_session(skb, &fl, family);
2408
2409 /* First, check used SA against their selectors. */
2410 if (skb->sp) {
2411 int i;
2412
2413 for (i = skb->sp->len-1; i >= 0; i--) {
2414 struct xfrm_state *x = skb->sp->xvec[i];
2415 if (!xfrm_selector_match(&x->sel, &fl, family)) {
2416 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2417 return 0;
2418 }
2419 }
2420 }
2421
2422 pol = NULL;
2423 sk = sk_to_full_sk(sk);
2424 if (sk && sk->sk_policy[dir]) {
2425 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family);
2426 if (IS_ERR(pol)) {
2427 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2428 return 0;
2429 }
2430 }
2431
2432 if (!pol)
2433 pol = xfrm_policy_lookup(net, &fl, family, dir);
2434
2435 if (IS_ERR(pol)) {
2436 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2437 return 0;
2438 }
2439
2440 if (!pol) {
2441 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2442 xfrm_secpath_reject(xerr_idx, skb, &fl);
2443 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2444 return 0;
2445 }
2446 return 1;
2447 }
2448
2449 pol->curlft.use_time = get_seconds();
2450
2451 pols[0] = pol;
2452 npols++;
2453#ifdef CONFIG_XFRM_SUB_POLICY
2454 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2455 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2456 &fl, family,
2457 XFRM_POLICY_IN);
2458 if (pols[1]) {
2459 if (IS_ERR(pols[1])) {
2460 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2461 return 0;
2462 }
2463 pols[1]->curlft.use_time = get_seconds();
2464 npols++;
2465 }
2466 }
2467#endif
2468
2469 if (pol->action == XFRM_POLICY_ALLOW) {
2470 struct sec_path *sp;
2471 static struct sec_path dummy;
2472 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2473 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2474 struct xfrm_tmpl **tpp = tp;
2475 int ti = 0;
2476 int i, k;
2477
2478 if ((sp = skb->sp) == NULL)
2479 sp = &dummy;
2480
2481 for (pi = 0; pi < npols; pi++) {
2482 if (pols[pi] != pol &&
2483 pols[pi]->action != XFRM_POLICY_ALLOW) {
2484 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2485 goto reject;
2486 }
2487 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2488 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2489 goto reject_error;
2490 }
2491 for (i = 0; i < pols[pi]->xfrm_nr; i++)
2492 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2493 }
2494 xfrm_nr = ti;
2495 if (npols > 1) {
2496 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2497 tpp = stp;
2498 }
2499
2500 /* For each tunnel xfrm, find the first matching tmpl.
2501 * For each tmpl before that, find corresponding xfrm.
2502 * Order is _important_. Later we will implement
2503 * some barriers, but at the moment barriers
2504 * are implied between each two transformations.
2505 */
2506 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2507 k = xfrm_policy_ok(tpp[i], sp, k, family);
2508 if (k < 0) {
2509 if (k < -1)
2510 /* "-2 - errored_index" returned */
2511 xerr_idx = -(2+k);
2512 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2513 goto reject;
2514 }
2515 }
2516
2517 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2518 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2519 goto reject;
2520 }
2521
2522 xfrm_pols_put(pols, npols);
2523 return 1;
2524 }
2525 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2526
2527reject:
2528 xfrm_secpath_reject(xerr_idx, skb, &fl);
2529reject_error:
2530 xfrm_pols_put(pols, npols);
2531 return 0;
2532}
2533EXPORT_SYMBOL(__xfrm_policy_check);
2534
2535int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2536{
2537 struct net *net = dev_net(skb->dev);
2538 struct flowi fl;
2539 struct dst_entry *dst;
2540 int res = 1;
2541
2542 if (xfrm_decode_session(skb, &fl, family) < 0) {
2543 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2544 return 0;
2545 }
2546
2547 skb_dst_force(skb);
2548
2549 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2550 if (IS_ERR(dst)) {
2551 res = 0;
2552 dst = NULL;
2553 }
2554 skb_dst_set(skb, dst);
2555 return res;
2556}
2557EXPORT_SYMBOL(__xfrm_route_forward);
2558
2559/* Optimize later using cookies and generation ids. */
2560
2561static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2562{
2563 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2564 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2565 * get validated by dst_ops->check on every use. We do this
2566 * because when a normal route referenced by an XFRM dst is
2567 * obsoleted we do not go looking around for all parent
2568 * referencing XFRM dsts so that we can invalidate them. It
2569 * is just too much work. Instead we make the checks here on
2570 * every use. For example:
2571 *
2572 * XFRM dst A --> IPv4 dst X
2573 *
2574 * X is the "xdst->route" of A (X is also the "dst->path" of A
2575 * in this example). If X is marked obsolete, "A" will not
2576 * notice. That's what we are validating here via the
2577 * stale_bundle() check.
2578 *
2579 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
2580 * be marked on it.
2581 * This will force stale_bundle() to fail on any xdst bundle with
2582 * this dst linked in it.
2583 */
2584 if (dst->obsolete < 0 && !stale_bundle(dst))
2585 return dst;
2586
2587 return NULL;
2588}
2589
2590static int stale_bundle(struct dst_entry *dst)
2591{
2592 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2593}
2594
2595void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2596{
2597 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
2598 dst->dev = dev_net(dev)->loopback_dev;
2599 dev_hold(dst->dev);
2600 dev_put(dev);
2601 }
2602}
2603EXPORT_SYMBOL(xfrm_dst_ifdown);
2604
2605static void xfrm_link_failure(struct sk_buff *skb)
2606{
2607 /* Impossible. Such dst must be popped before reaches point of failure. */
2608}
2609
2610static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2611{
2612 if (dst) {
2613 if (dst->obsolete) {
2614 dst_release(dst);
2615 dst = NULL;
2616 }
2617 }
2618 return dst;
2619}
2620
2621static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
2622{
2623 while (nr--) {
2624 struct xfrm_dst *xdst = bundle[nr];
2625 u32 pmtu, route_mtu_cached;
2626 struct dst_entry *dst;
2627
2628 dst = &xdst->u.dst;
2629 pmtu = dst_mtu(xfrm_dst_child(dst));
2630 xdst->child_mtu_cached = pmtu;
2631
2632 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2633
2634 route_mtu_cached = dst_mtu(xdst->route);
2635 xdst->route_mtu_cached = route_mtu_cached;
2636
2637 if (pmtu > route_mtu_cached)
2638 pmtu = route_mtu_cached;
2639
2640 dst_metric_set(dst, RTAX_MTU, pmtu);
2641 }
2642}
2643
2644/* Check that the bundle accepts the flow and its components are
2645 * still valid.
2646 */
2647
2648static int xfrm_bundle_ok(struct xfrm_dst *first)
2649{
2650 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2651 struct dst_entry *dst = &first->u.dst;
2652 struct xfrm_dst *xdst;
2653 int start_from, nr;
2654 u32 mtu;
2655
2656 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
2657 (dst->dev && !netif_running(dst->dev)))
2658 return 0;
2659
2660 if (dst->flags & DST_XFRM_QUEUE)
2661 return 1;
2662
2663 start_from = nr = 0;
2664 do {
2665 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2666
2667 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2668 return 0;
2669 if (xdst->xfrm_genid != dst->xfrm->genid)
2670 return 0;
2671 if (xdst->num_pols > 0 &&
2672 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2673 return 0;
2674
2675 bundle[nr++] = xdst;
2676
2677 mtu = dst_mtu(xfrm_dst_child(dst));
2678 if (xdst->child_mtu_cached != mtu) {
2679 start_from = nr;
2680 xdst->child_mtu_cached = mtu;
2681 }
2682
2683 if (!dst_check(xdst->route, xdst->route_cookie))
2684 return 0;
2685 mtu = dst_mtu(xdst->route);
2686 if (xdst->route_mtu_cached != mtu) {
2687 start_from = nr;
2688 xdst->route_mtu_cached = mtu;
2689 }
2690
2691 dst = xfrm_dst_child(dst);
2692 } while (dst->xfrm);
2693
2694 if (likely(!start_from))
2695 return 1;
2696
2697 xdst = bundle[start_from - 1];
2698 mtu = xdst->child_mtu_cached;
2699 while (start_from--) {
2700 dst = &xdst->u.dst;
2701
2702 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2703 if (mtu > xdst->route_mtu_cached)
2704 mtu = xdst->route_mtu_cached;
2705 dst_metric_set(dst, RTAX_MTU, mtu);
2706 if (!start_from)
2707 break;
2708
2709 xdst = bundle[start_from - 1];
2710 xdst->child_mtu_cached = mtu;
2711 }
2712
2713 return 1;
2714}
2715
2716static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2717{
2718 return dst_metric_advmss(xfrm_dst_path(dst));
2719}
2720
2721static unsigned int xfrm_mtu(const struct dst_entry *dst)
2722{
2723 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2724
2725 return mtu ? : dst_mtu(xfrm_dst_path(dst));
2726}
2727
2728static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2729 const void *daddr)
2730{
2731 while (dst->xfrm) {
2732 const struct xfrm_state *xfrm = dst->xfrm;
2733
2734 dst = xfrm_dst_child(dst);
2735
2736 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2737 continue;
2738 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2739 daddr = xfrm->coaddr;
2740 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2741 daddr = &xfrm->id.daddr;
2742 }
2743 return daddr;
2744}
2745
2746static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2747 struct sk_buff *skb,
2748 const void *daddr)
2749{
2750 const struct dst_entry *path = xfrm_dst_path(dst);
2751
2752 if (!skb)
2753 daddr = xfrm_get_dst_nexthop(dst, daddr);
2754 return path->ops->neigh_lookup(path, skb, daddr);
2755}
2756
2757static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2758{
2759 const struct dst_entry *path = xfrm_dst_path(dst);
2760
2761 daddr = xfrm_get_dst_nexthop(dst, daddr);
2762 path->ops->confirm_neigh(path, daddr);
2763}
2764
2765int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2766{
2767 int err = 0;
2768
2769 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2770 return -EAFNOSUPPORT;
2771
2772 spin_lock(&xfrm_policy_afinfo_lock);
2773 if (unlikely(xfrm_policy_afinfo[family] != NULL))
2774 err = -EEXIST;
2775 else {
2776 struct dst_ops *dst_ops = afinfo->dst_ops;
2777 if (likely(dst_ops->kmem_cachep == NULL))
2778 dst_ops->kmem_cachep = xfrm_dst_cache;
2779 if (likely(dst_ops->check == NULL))
2780 dst_ops->check = xfrm_dst_check;
2781 if (likely(dst_ops->default_advmss == NULL))
2782 dst_ops->default_advmss = xfrm_default_advmss;
2783 if (likely(dst_ops->mtu == NULL))
2784 dst_ops->mtu = xfrm_mtu;
2785 if (likely(dst_ops->negative_advice == NULL))
2786 dst_ops->negative_advice = xfrm_negative_advice;
2787 if (likely(dst_ops->link_failure == NULL))
2788 dst_ops->link_failure = xfrm_link_failure;
2789 if (likely(dst_ops->neigh_lookup == NULL))
2790 dst_ops->neigh_lookup = xfrm_neigh_lookup;
2791 if (likely(!dst_ops->confirm_neigh))
2792 dst_ops->confirm_neigh = xfrm_confirm_neigh;
2793 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2794 }
2795 spin_unlock(&xfrm_policy_afinfo_lock);
2796
2797 return err;
2798}
2799EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2800
2801void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2802{
2803 struct dst_ops *dst_ops = afinfo->dst_ops;
2804 int i;
2805
2806 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2807 if (xfrm_policy_afinfo[i] != afinfo)
2808 continue;
2809 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2810 break;
2811 }
2812
2813 synchronize_rcu();
2814
2815 dst_ops->kmem_cachep = NULL;
2816 dst_ops->check = NULL;
2817 dst_ops->negative_advice = NULL;
2818 dst_ops->link_failure = NULL;
2819}
2820EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2821
2822#ifdef CONFIG_XFRM_STATISTICS
2823static int __net_init xfrm_statistics_init(struct net *net)
2824{
2825 int rv;
2826 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2827 if (!net->mib.xfrm_statistics)
2828 return -ENOMEM;
2829 rv = xfrm_proc_init(net);
2830 if (rv < 0)
2831 free_percpu(net->mib.xfrm_statistics);
2832 return rv;
2833}
2834
2835static void xfrm_statistics_fini(struct net *net)
2836{
2837 xfrm_proc_fini(net);
2838 free_percpu(net->mib.xfrm_statistics);
2839}
2840#else
2841static int __net_init xfrm_statistics_init(struct net *net)
2842{
2843 return 0;
2844}
2845
2846static void xfrm_statistics_fini(struct net *net)
2847{
2848}
2849#endif
2850
2851static int __net_init xfrm_policy_init(struct net *net)
2852{
2853 unsigned int hmask, sz;
2854 int dir;
2855
2856 if (net_eq(net, &init_net))
2857 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2858 sizeof(struct xfrm_dst),
2859 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2860 NULL);
2861
2862 hmask = 8 - 1;
2863 sz = (hmask+1) * sizeof(struct hlist_head);
2864
2865 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2866 if (!net->xfrm.policy_byidx)
2867 goto out_byidx;
2868 net->xfrm.policy_idx_hmask = hmask;
2869
2870 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2871 struct xfrm_policy_hash *htab;
2872
2873 net->xfrm.policy_count[dir] = 0;
2874 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2875 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2876
2877 htab = &net->xfrm.policy_bydst[dir];
2878 htab->table = xfrm_hash_alloc(sz);
2879 if (!htab->table)
2880 goto out_bydst;
2881 htab->hmask = hmask;
2882 htab->dbits4 = 32;
2883 htab->sbits4 = 32;
2884 htab->dbits6 = 128;
2885 htab->sbits6 = 128;
2886 }
2887 net->xfrm.policy_hthresh.lbits4 = 32;
2888 net->xfrm.policy_hthresh.rbits4 = 32;
2889 net->xfrm.policy_hthresh.lbits6 = 128;
2890 net->xfrm.policy_hthresh.rbits6 = 128;
2891
2892 seqlock_init(&net->xfrm.policy_hthresh.lock);
2893
2894 INIT_LIST_HEAD(&net->xfrm.policy_all);
2895 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2896 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2897 return 0;
2898
2899out_bydst:
2900 for (dir--; dir >= 0; dir--) {
2901 struct xfrm_policy_hash *htab;
2902
2903 htab = &net->xfrm.policy_bydst[dir];
2904 xfrm_hash_free(htab->table, sz);
2905 }
2906 xfrm_hash_free(net->xfrm.policy_byidx, sz);
2907out_byidx:
2908 return -ENOMEM;
2909}
2910
2911static void xfrm_policy_fini(struct net *net)
2912{
2913 unsigned int sz;
2914 int dir;
2915
2916 flush_work(&net->xfrm.policy_hash_work);
2917#ifdef CONFIG_XFRM_SUB_POLICY
2918 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
2919#endif
2920 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
2921
2922 WARN_ON(!list_empty(&net->xfrm.policy_all));
2923
2924 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2925 struct xfrm_policy_hash *htab;
2926
2927 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2928
2929 htab = &net->xfrm.policy_bydst[dir];
2930 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2931 WARN_ON(!hlist_empty(htab->table));
2932 xfrm_hash_free(htab->table, sz);
2933 }
2934
2935 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2936 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2937 xfrm_hash_free(net->xfrm.policy_byidx, sz);
2938}
2939
2940static int __net_init xfrm_net_init(struct net *net)
2941{
2942 int rv;
2943
2944 /* Initialize the per-net locks here */
2945 spin_lock_init(&net->xfrm.xfrm_state_lock);
2946 spin_lock_init(&net->xfrm.xfrm_policy_lock);
2947 mutex_init(&net->xfrm.xfrm_cfg_mutex);
2948
2949 rv = xfrm_statistics_init(net);
2950 if (rv < 0)
2951 goto out_statistics;
2952 rv = xfrm_state_init(net);
2953 if (rv < 0)
2954 goto out_state;
2955 rv = xfrm_policy_init(net);
2956 if (rv < 0)
2957 goto out_policy;
2958 rv = xfrm_sysctl_init(net);
2959 if (rv < 0)
2960 goto out_sysctl;
2961
2962 return 0;
2963
2964out_sysctl:
2965 xfrm_policy_fini(net);
2966out_policy:
2967 xfrm_state_fini(net);
2968out_state:
2969 xfrm_statistics_fini(net);
2970out_statistics:
2971 return rv;
2972}
2973
2974static void __net_exit xfrm_net_exit(struct net *net)
2975{
2976 xfrm_sysctl_fini(net);
2977 xfrm_policy_fini(net);
2978 xfrm_state_fini(net);
2979 xfrm_statistics_fini(net);
2980}
2981
2982static struct pernet_operations __net_initdata xfrm_net_ops = {
2983 .init = xfrm_net_init,
2984 .exit = xfrm_net_exit,
2985};
2986
2987void __init xfrm_init(void)
2988{
2989 int i;
2990
2991 xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work),
2992 GFP_KERNEL);
2993 BUG_ON(!xfrm_pcpu_work);
2994
2995 for (i = 0; i < NR_CPUS; i++)
2996 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn);
2997
2998 register_pernet_subsys(&xfrm_net_ops);
2999 xfrm_dev_init();
3000 seqcount_init(&xfrm_policy_hash_generation);
3001 xfrm_input_init();
3002}
3003
3004#ifdef CONFIG_AUDITSYSCALL
3005static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3006 struct audit_buffer *audit_buf)
3007{
3008 struct xfrm_sec_ctx *ctx = xp->security;
3009 struct xfrm_selector *sel = &xp->selector;
3010
3011 if (ctx)
3012 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3013 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3014
3015 switch (sel->family) {
3016 case AF_INET:
3017 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3018 if (sel->prefixlen_s != 32)
3019 audit_log_format(audit_buf, " src_prefixlen=%d",
3020 sel->prefixlen_s);
3021 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3022 if (sel->prefixlen_d != 32)
3023 audit_log_format(audit_buf, " dst_prefixlen=%d",
3024 sel->prefixlen_d);
3025 break;
3026 case AF_INET6:
3027 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3028 if (sel->prefixlen_s != 128)
3029 audit_log_format(audit_buf, " src_prefixlen=%d",
3030 sel->prefixlen_s);
3031 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3032 if (sel->prefixlen_d != 128)
3033 audit_log_format(audit_buf, " dst_prefixlen=%d",
3034 sel->prefixlen_d);
3035 break;
3036 }
3037}
3038
3039void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3040{
3041 struct audit_buffer *audit_buf;
3042
3043 audit_buf = xfrm_audit_start("SPD-add");
3044 if (audit_buf == NULL)
3045 return;
3046 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3047 audit_log_format(audit_buf, " res=%u", result);
3048 xfrm_audit_common_policyinfo(xp, audit_buf);
3049 audit_log_end(audit_buf);
3050}
3051EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3052
3053void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3054 bool task_valid)
3055{
3056 struct audit_buffer *audit_buf;
3057
3058 audit_buf = xfrm_audit_start("SPD-delete");
3059 if (audit_buf == NULL)
3060 return;
3061 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3062 audit_log_format(audit_buf, " res=%u", result);
3063 xfrm_audit_common_policyinfo(xp, audit_buf);
3064 audit_log_end(audit_buf);
3065}
3066EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3067#endif
3068
3069#ifdef CONFIG_XFRM_MIGRATE
3070static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3071 const struct xfrm_selector *sel_tgt)
3072{
3073 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3074 if (sel_tgt->family == sel_cmp->family &&
3075 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3076 sel_cmp->family) &&
3077 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3078 sel_cmp->family) &&
3079 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3080 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3081 return true;
3082 }
3083 } else {
3084 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3085 return true;
3086 }
3087 }
3088 return false;
3089}
3090
3091static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3092 u8 dir, u8 type, struct net *net)
3093{
3094 struct xfrm_policy *pol, *ret = NULL;
3095 struct hlist_head *chain;
3096 u32 priority = ~0U;
3097
3098 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3099 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3100 hlist_for_each_entry(pol, chain, bydst) {
3101 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3102 pol->type == type) {
3103 ret = pol;
3104 priority = ret->priority;
3105 break;
3106 }
3107 }
3108 chain = &net->xfrm.policy_inexact[dir];
3109 hlist_for_each_entry(pol, chain, bydst) {
3110 if ((pol->priority >= priority) && ret)
3111 break;
3112
3113 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3114 pol->type == type) {
3115 ret = pol;
3116 break;
3117 }
3118 }
3119
3120 xfrm_pol_hold(ret);
3121
3122 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3123
3124 return ret;
3125}
3126
3127static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3128{
3129 int match = 0;
3130
3131 if (t->mode == m->mode && t->id.proto == m->proto &&
3132 (m->reqid == 0 || t->reqid == m->reqid)) {
3133 switch (t->mode) {
3134 case XFRM_MODE_TUNNEL:
3135 case XFRM_MODE_BEET:
3136 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3137 m->old_family) &&
3138 xfrm_addr_equal(&t->saddr, &m->old_saddr,
3139 m->old_family)) {
3140 match = 1;
3141 }
3142 break;
3143 case XFRM_MODE_TRANSPORT:
3144 /* in case of transport mode, template does not store
3145 any IP addresses, hence we just compare mode and
3146 protocol */
3147 match = 1;
3148 break;
3149 default:
3150 break;
3151 }
3152 }
3153 return match;
3154}
3155
3156/* update endpoint address(es) of template(s) */
3157static int xfrm_policy_migrate(struct xfrm_policy *pol,
3158 struct xfrm_migrate *m, int num_migrate)
3159{
3160 struct xfrm_migrate *mp;
3161 int i, j, n = 0;
3162
3163 write_lock_bh(&pol->lock);
3164 if (unlikely(pol->walk.dead)) {
3165 /* target policy has been deleted */
3166 write_unlock_bh(&pol->lock);
3167 return -ENOENT;
3168 }
3169
3170 for (i = 0; i < pol->xfrm_nr; i++) {
3171 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3172 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3173 continue;
3174 n++;
3175 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3176 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3177 continue;
3178 /* update endpoints */
3179 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3180 sizeof(pol->xfrm_vec[i].id.daddr));
3181 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3182 sizeof(pol->xfrm_vec[i].saddr));
3183 pol->xfrm_vec[i].encap_family = mp->new_family;
3184 /* flush bundles */
3185 atomic_inc(&pol->genid);
3186 }
3187 }
3188
3189 write_unlock_bh(&pol->lock);
3190
3191 if (!n)
3192 return -ENODATA;
3193
3194 return 0;
3195}
3196
3197static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3198{
3199 int i, j;
3200
3201 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3202 return -EINVAL;
3203
3204 for (i = 0; i < num_migrate; i++) {
3205 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3206 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3207 return -EINVAL;
3208
3209 /* check if there is any duplicated entry */
3210 for (j = i + 1; j < num_migrate; j++) {
3211 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3212 sizeof(m[i].old_daddr)) &&
3213 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3214 sizeof(m[i].old_saddr)) &&
3215 m[i].proto == m[j].proto &&
3216 m[i].mode == m[j].mode &&
3217 m[i].reqid == m[j].reqid &&
3218 m[i].old_family == m[j].old_family)
3219 return -EINVAL;
3220 }
3221 }
3222
3223 return 0;
3224}
3225
3226int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3227 struct xfrm_migrate *m, int num_migrate,
3228 struct xfrm_kmaddress *k, struct net *net,
3229 struct xfrm_encap_tmpl *encap)
3230{
3231 int i, err, nx_cur = 0, nx_new = 0;
3232 struct xfrm_policy *pol = NULL;
3233 struct xfrm_state *x, *xc;
3234 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3235 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3236 struct xfrm_migrate *mp;
3237
3238 /* Stage 0 - sanity checks */
3239 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3240 goto out;
3241
3242 if (dir >= XFRM_POLICY_MAX) {
3243 err = -EINVAL;
3244 goto out;
3245 }
3246
3247 /* Stage 1 - find policy */
3248 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3249 err = -ENOENT;
3250 goto out;
3251 }
3252
3253 /* Stage 2 - find and update state(s) */
3254 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3255 if ((x = xfrm_migrate_state_find(mp, net))) {
3256 x_cur[nx_cur] = x;
3257 nx_cur++;
3258 xc = xfrm_state_migrate(x, mp, encap);
3259 if (xc) {
3260 x_new[nx_new] = xc;
3261 nx_new++;
3262 } else {
3263 err = -ENODATA;
3264 goto restore_state;
3265 }
3266 }
3267 }
3268
3269 /* Stage 3 - update policy */
3270 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3271 goto restore_state;
3272
3273 /* Stage 4 - delete old state(s) */
3274 if (nx_cur) {
3275 xfrm_states_put(x_cur, nx_cur);
3276 xfrm_states_delete(x_cur, nx_cur);
3277 }
3278
3279 /* Stage 5 - announce */
3280 km_migrate(sel, dir, type, m, num_migrate, k, encap);
3281
3282 xfrm_pol_put(pol);
3283
3284 return 0;
3285out:
3286 return err;
3287
3288restore_state:
3289 if (pol)
3290 xfrm_pol_put(pol);
3291 if (nx_cur)
3292 xfrm_states_put(x_cur, nx_cur);
3293 if (nx_new)
3294 xfrm_states_delete(x_new, nx_new);
3295
3296 return err;
3297}
3298EXPORT_SYMBOL(xfrm_migrate);
3299#endif