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 <net/dst.h>
33 #include <net/flow.h>
34 #include <net/inet_ecn.h>
35 #include <net/xfrm.h>
36 #include <net/ip.h>
37 #include <net/gre.h>
38 #if IS_ENABLED(CONFIG_IPV6_MIP6)
39 #include <net/mip6.h>
40 #endif
41 #ifdef CONFIG_XFRM_STATISTICS
42 #include <net/snmp.h>
43 #endif
44 #ifdef CONFIG_XFRM_ESPINTCP
45 #include <net/espintcp.h>
46 #endif
47
48 #include "xfrm_hash.h"
49
50 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
51 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
52 #define XFRM_MAX_QUEUE_LEN 100
53
54 struct xfrm_flo {
55 struct dst_entry *dst_orig;
56 u8 flags;
57 };
58
59 /* prefixes smaller than this are stored in lists, not trees. */
60 #define INEXACT_PREFIXLEN_IPV4 16
61 #define INEXACT_PREFIXLEN_IPV6 48
62
63 struct xfrm_pol_inexact_node {
64 struct rb_node node;
65 union {
66 xfrm_address_t addr;
67 struct rcu_head rcu;
68 };
69 u8 prefixlen;
70
71 struct rb_root root;
72
73 /* the policies matching this node, can be empty list */
74 struct hlist_head hhead;
75 };
76
77 /* xfrm inexact policy search tree:
78 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
79 * |
80 * +---- root_d: sorted by daddr:prefix
81 * | |
82 * | xfrm_pol_inexact_node
83 * | |
84 * | +- root: sorted by saddr/prefix
85 * | | |
86 * | | xfrm_pol_inexact_node
87 * | | |
88 * | | + root: unused
89 * | | |
90 * | | + hhead: saddr:daddr policies
91 * | |
92 * | +- coarse policies and all any:daddr policies
93 * |
94 * +---- root_s: sorted by saddr:prefix
95 * | |
96 * | xfrm_pol_inexact_node
97 * | |
98 * | + root: unused
99 * | |
100 * | + hhead: saddr:any policies
101 * |
102 * +---- coarse policies and all any:any policies
103 *
104 * Lookups return four candidate lists:
105 * 1. any:any list from top-level xfrm_pol_inexact_bin
106 * 2. any:daddr list from daddr tree
107 * 3. saddr:daddr list from 2nd level daddr tree
108 * 4. saddr:any list from saddr tree
109 *
110 * This result set then needs to be searched for the policy with
111 * the lowest priority. If two results have same prio, youngest one wins.
112 */
113
114 struct xfrm_pol_inexact_key {
115 possible_net_t net;
116 u32 if_id;
117 u16 family;
118 u8 dir, type;
119 };
120
121 struct xfrm_pol_inexact_bin {
122 struct xfrm_pol_inexact_key k;
123 struct rhash_head head;
124 /* list containing '*:*' policies */
125 struct hlist_head hhead;
126
127 seqcount_spinlock_t count;
128 /* tree sorted by daddr/prefix */
129 struct rb_root root_d;
130
131 /* tree sorted by saddr/prefix */
132 struct rb_root root_s;
133
134 /* slow path below */
135 struct list_head inexact_bins;
136 struct rcu_head rcu;
137 };
138
139 enum xfrm_pol_inexact_candidate_type {
140 XFRM_POL_CAND_BOTH,
141 XFRM_POL_CAND_SADDR,
142 XFRM_POL_CAND_DADDR,
143 XFRM_POL_CAND_ANY,
144
145 XFRM_POL_CAND_MAX,
146 };
147
148 struct xfrm_pol_inexact_candidates {
149 struct hlist_head *res[XFRM_POL_CAND_MAX];
150 };
151
152 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
153 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
154
155 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
156 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
157 __read_mostly;
158
159 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
160
161 static struct rhashtable xfrm_policy_inexact_table;
162 static const struct rhashtable_params xfrm_pol_inexact_params;
163
164 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
165 static int stale_bundle(struct dst_entry *dst);
166 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
167 static void xfrm_policy_queue_process(struct timer_list *t);
168
169 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
170 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
171 int dir);
172
173 static struct xfrm_pol_inexact_bin *
174 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
175 u32 if_id);
176
177 static struct xfrm_pol_inexact_bin *
178 xfrm_policy_inexact_lookup_rcu(struct net *net,
179 u8 type, u16 family, u8 dir, u32 if_id);
180 static struct xfrm_policy *
181 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
182 bool excl);
183 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
184 struct xfrm_policy *policy);
185
186 static bool
187 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
188 struct xfrm_pol_inexact_bin *b,
189 const xfrm_address_t *saddr,
190 const xfrm_address_t *daddr);
191
xfrm_pol_hold_rcu(struct xfrm_policy * policy)192 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
193 {
194 return refcount_inc_not_zero(&policy->refcnt);
195 }
196
197 static inline bool
__xfrm4_selector_match(const struct xfrm_selector * sel,const struct flowi * fl)198 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
199 {
200 const struct flowi4 *fl4 = &fl->u.ip4;
201
202 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
203 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
204 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
205 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
206 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
207 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
208 }
209
210 static inline bool
__xfrm6_selector_match(const struct xfrm_selector * sel,const struct flowi * fl)211 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
212 {
213 const struct flowi6 *fl6 = &fl->u.ip6;
214
215 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
216 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
217 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
218 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
219 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
220 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
221 }
222
xfrm_selector_match(const struct xfrm_selector * sel,const struct flowi * fl,unsigned short family)223 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
224 unsigned short family)
225 {
226 switch (family) {
227 case AF_INET:
228 return __xfrm4_selector_match(sel, fl);
229 case AF_INET6:
230 return __xfrm6_selector_match(sel, fl);
231 }
232 return false;
233 }
234
xfrm_policy_get_afinfo(unsigned short family)235 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
236 {
237 const struct xfrm_policy_afinfo *afinfo;
238
239 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
240 return NULL;
241 rcu_read_lock();
242 afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
243 if (unlikely(!afinfo))
244 rcu_read_unlock();
245 return afinfo;
246 }
247
248 /* Called with rcu_read_lock(). */
xfrm_if_get_cb(void)249 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
250 {
251 return rcu_dereference(xfrm_if_cb);
252 }
253
__xfrm_dst_lookup(struct net * net,int tos,int oif,const xfrm_address_t * saddr,const xfrm_address_t * daddr,int family,u32 mark)254 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
255 const xfrm_address_t *saddr,
256 const xfrm_address_t *daddr,
257 int family, u32 mark)
258 {
259 const struct xfrm_policy_afinfo *afinfo;
260 struct dst_entry *dst;
261
262 afinfo = xfrm_policy_get_afinfo(family);
263 if (unlikely(afinfo == NULL))
264 return ERR_PTR(-EAFNOSUPPORT);
265
266 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
267
268 rcu_read_unlock();
269
270 return dst;
271 }
272 EXPORT_SYMBOL(__xfrm_dst_lookup);
273
xfrm_dst_lookup(struct xfrm_state * x,int tos,int oif,xfrm_address_t * prev_saddr,xfrm_address_t * prev_daddr,int family,u32 mark)274 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
275 int tos, int oif,
276 xfrm_address_t *prev_saddr,
277 xfrm_address_t *prev_daddr,
278 int family, u32 mark)
279 {
280 struct net *net = xs_net(x);
281 xfrm_address_t *saddr = &x->props.saddr;
282 xfrm_address_t *daddr = &x->id.daddr;
283 struct dst_entry *dst;
284
285 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
286 saddr = x->coaddr;
287 daddr = prev_daddr;
288 }
289 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
290 saddr = prev_saddr;
291 daddr = x->coaddr;
292 }
293
294 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
295
296 if (!IS_ERR(dst)) {
297 if (prev_saddr != saddr)
298 memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
299 if (prev_daddr != daddr)
300 memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
301 }
302
303 return dst;
304 }
305
make_jiffies(long secs)306 static inline unsigned long make_jiffies(long secs)
307 {
308 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
309 return MAX_SCHEDULE_TIMEOUT-1;
310 else
311 return secs*HZ;
312 }
313
xfrm_policy_timer(struct timer_list * t)314 static void xfrm_policy_timer(struct timer_list *t)
315 {
316 struct xfrm_policy *xp = from_timer(xp, t, timer);
317 time64_t now = ktime_get_real_seconds();
318 time64_t next = TIME64_MAX;
319 int warn = 0;
320 int dir;
321
322 read_lock(&xp->lock);
323
324 if (unlikely(xp->walk.dead))
325 goto out;
326
327 dir = xfrm_policy_id2dir(xp->index);
328
329 if (xp->lft.hard_add_expires_seconds) {
330 time64_t tmo = xp->lft.hard_add_expires_seconds +
331 xp->curlft.add_time - now;
332 if (tmo <= 0)
333 goto expired;
334 if (tmo < next)
335 next = tmo;
336 }
337 if (xp->lft.hard_use_expires_seconds) {
338 time64_t tmo = xp->lft.hard_use_expires_seconds +
339 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
340 if (tmo <= 0)
341 goto expired;
342 if (tmo < next)
343 next = tmo;
344 }
345 if (xp->lft.soft_add_expires_seconds) {
346 time64_t tmo = xp->lft.soft_add_expires_seconds +
347 xp->curlft.add_time - now;
348 if (tmo <= 0) {
349 warn = 1;
350 tmo = XFRM_KM_TIMEOUT;
351 }
352 if (tmo < next)
353 next = tmo;
354 }
355 if (xp->lft.soft_use_expires_seconds) {
356 time64_t tmo = xp->lft.soft_use_expires_seconds +
357 (xp->curlft.use_time ? : xp->curlft.add_time) - now;
358 if (tmo <= 0) {
359 warn = 1;
360 tmo = XFRM_KM_TIMEOUT;
361 }
362 if (tmo < next)
363 next = tmo;
364 }
365
366 if (warn)
367 km_policy_expired(xp, dir, 0, 0);
368 if (next != TIME64_MAX &&
369 !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
370 xfrm_pol_hold(xp);
371
372 out:
373 read_unlock(&xp->lock);
374 xfrm_pol_put(xp);
375 return;
376
377 expired:
378 read_unlock(&xp->lock);
379 if (!xfrm_policy_delete(xp, dir))
380 km_policy_expired(xp, dir, 1, 0);
381 xfrm_pol_put(xp);
382 }
383
384 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
385 * SPD calls.
386 */
387
xfrm_policy_alloc(struct net * net,gfp_t gfp)388 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
389 {
390 struct xfrm_policy *policy;
391
392 policy = kzalloc(sizeof(struct xfrm_policy), gfp);
393
394 if (policy) {
395 write_pnet(&policy->xp_net, net);
396 INIT_LIST_HEAD(&policy->walk.all);
397 INIT_HLIST_NODE(&policy->bydst_inexact_list);
398 INIT_HLIST_NODE(&policy->bydst);
399 INIT_HLIST_NODE(&policy->byidx);
400 rwlock_init(&policy->lock);
401 refcount_set(&policy->refcnt, 1);
402 skb_queue_head_init(&policy->polq.hold_queue);
403 timer_setup(&policy->timer, xfrm_policy_timer, 0);
404 timer_setup(&policy->polq.hold_timer,
405 xfrm_policy_queue_process, 0);
406 }
407 return policy;
408 }
409 EXPORT_SYMBOL(xfrm_policy_alloc);
410
xfrm_policy_destroy_rcu(struct rcu_head * head)411 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
412 {
413 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
414
415 security_xfrm_policy_free(policy->security);
416 kfree(policy);
417 }
418
419 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
420
xfrm_policy_destroy(struct xfrm_policy * policy)421 void xfrm_policy_destroy(struct xfrm_policy *policy)
422 {
423 BUG_ON(!policy->walk.dead);
424
425 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
426 BUG();
427
428 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
429 }
430 EXPORT_SYMBOL(xfrm_policy_destroy);
431
432 /* Rule must be locked. Release descendant resources, announce
433 * entry dead. The rule must be unlinked from lists to the moment.
434 */
435
xfrm_policy_kill(struct xfrm_policy * policy)436 static void xfrm_policy_kill(struct xfrm_policy *policy)
437 {
438 write_lock_bh(&policy->lock);
439 policy->walk.dead = 1;
440 write_unlock_bh(&policy->lock);
441
442 atomic_inc(&policy->genid);
443
444 if (del_timer(&policy->polq.hold_timer))
445 xfrm_pol_put(policy);
446 skb_queue_purge(&policy->polq.hold_queue);
447
448 if (del_timer(&policy->timer))
449 xfrm_pol_put(policy);
450
451 xfrm_pol_put(policy);
452 }
453
454 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
455
idx_hash(struct net * net,u32 index)456 static inline unsigned int idx_hash(struct net *net, u32 index)
457 {
458 return __idx_hash(index, net->xfrm.policy_idx_hmask);
459 }
460
461 /* calculate policy hash thresholds */
__get_hash_thresh(struct net * net,unsigned short family,int dir,u8 * dbits,u8 * sbits)462 static void __get_hash_thresh(struct net *net,
463 unsigned short family, int dir,
464 u8 *dbits, u8 *sbits)
465 {
466 switch (family) {
467 case AF_INET:
468 *dbits = net->xfrm.policy_bydst[dir].dbits4;
469 *sbits = net->xfrm.policy_bydst[dir].sbits4;
470 break;
471
472 case AF_INET6:
473 *dbits = net->xfrm.policy_bydst[dir].dbits6;
474 *sbits = net->xfrm.policy_bydst[dir].sbits6;
475 break;
476
477 default:
478 *dbits = 0;
479 *sbits = 0;
480 }
481 }
482
policy_hash_bysel(struct net * net,const struct xfrm_selector * sel,unsigned short family,int dir)483 static struct hlist_head *policy_hash_bysel(struct net *net,
484 const struct xfrm_selector *sel,
485 unsigned short family, int dir)
486 {
487 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
488 unsigned int hash;
489 u8 dbits;
490 u8 sbits;
491
492 __get_hash_thresh(net, family, dir, &dbits, &sbits);
493 hash = __sel_hash(sel, family, hmask, dbits, sbits);
494
495 if (hash == hmask + 1)
496 return NULL;
497
498 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
499 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
500 }
501
policy_hash_direct(struct net * net,const xfrm_address_t * daddr,const xfrm_address_t * saddr,unsigned short family,int dir)502 static struct hlist_head *policy_hash_direct(struct net *net,
503 const xfrm_address_t *daddr,
504 const xfrm_address_t *saddr,
505 unsigned short family, int dir)
506 {
507 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
508 unsigned int hash;
509 u8 dbits;
510 u8 sbits;
511
512 __get_hash_thresh(net, family, dir, &dbits, &sbits);
513 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
514
515 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
516 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
517 }
518
xfrm_dst_hash_transfer(struct net * net,struct hlist_head * list,struct hlist_head * ndsttable,unsigned int nhashmask,int dir)519 static void xfrm_dst_hash_transfer(struct net *net,
520 struct hlist_head *list,
521 struct hlist_head *ndsttable,
522 unsigned int nhashmask,
523 int dir)
524 {
525 struct hlist_node *tmp, *entry0 = NULL;
526 struct xfrm_policy *pol;
527 unsigned int h0 = 0;
528 u8 dbits;
529 u8 sbits;
530
531 redo:
532 hlist_for_each_entry_safe(pol, tmp, list, bydst) {
533 unsigned int h;
534
535 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
536 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
537 pol->family, nhashmask, dbits, sbits);
538 if (!entry0) {
539 hlist_del_rcu(&pol->bydst);
540 hlist_add_head_rcu(&pol->bydst, ndsttable + h);
541 h0 = h;
542 } else {
543 if (h != h0)
544 continue;
545 hlist_del_rcu(&pol->bydst);
546 hlist_add_behind_rcu(&pol->bydst, entry0);
547 }
548 entry0 = &pol->bydst;
549 }
550 if (!hlist_empty(list)) {
551 entry0 = NULL;
552 goto redo;
553 }
554 }
555
xfrm_idx_hash_transfer(struct hlist_head * list,struct hlist_head * nidxtable,unsigned int nhashmask)556 static void xfrm_idx_hash_transfer(struct hlist_head *list,
557 struct hlist_head *nidxtable,
558 unsigned int nhashmask)
559 {
560 struct hlist_node *tmp;
561 struct xfrm_policy *pol;
562
563 hlist_for_each_entry_safe(pol, tmp, list, byidx) {
564 unsigned int h;
565
566 h = __idx_hash(pol->index, nhashmask);
567 hlist_add_head(&pol->byidx, nidxtable+h);
568 }
569 }
570
xfrm_new_hash_mask(unsigned int old_hmask)571 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
572 {
573 return ((old_hmask + 1) << 1) - 1;
574 }
575
xfrm_bydst_resize(struct net * net,int dir)576 static void xfrm_bydst_resize(struct net *net, int dir)
577 {
578 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
579 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
580 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
581 struct hlist_head *ndst = xfrm_hash_alloc(nsize);
582 struct hlist_head *odst;
583 int i;
584
585 if (!ndst)
586 return;
587
588 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
589 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
590
591 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
592 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
593
594 for (i = hmask; i >= 0; i--)
595 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
596
597 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
598 net->xfrm.policy_bydst[dir].hmask = nhashmask;
599
600 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
601 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
602
603 synchronize_rcu();
604
605 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
606 }
607
xfrm_byidx_resize(struct net * net,int total)608 static void xfrm_byidx_resize(struct net *net, int total)
609 {
610 unsigned int hmask = net->xfrm.policy_idx_hmask;
611 unsigned int nhashmask = xfrm_new_hash_mask(hmask);
612 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
613 struct hlist_head *oidx = net->xfrm.policy_byidx;
614 struct hlist_head *nidx = xfrm_hash_alloc(nsize);
615 int i;
616
617 if (!nidx)
618 return;
619
620 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
621
622 for (i = hmask; i >= 0; i--)
623 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
624
625 net->xfrm.policy_byidx = nidx;
626 net->xfrm.policy_idx_hmask = nhashmask;
627
628 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
629
630 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
631 }
632
xfrm_bydst_should_resize(struct net * net,int dir,int * total)633 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
634 {
635 unsigned int cnt = net->xfrm.policy_count[dir];
636 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
637
638 if (total)
639 *total += cnt;
640
641 if ((hmask + 1) < xfrm_policy_hashmax &&
642 cnt > hmask)
643 return 1;
644
645 return 0;
646 }
647
xfrm_byidx_should_resize(struct net * net,int total)648 static inline int xfrm_byidx_should_resize(struct net *net, int total)
649 {
650 unsigned int hmask = net->xfrm.policy_idx_hmask;
651
652 if ((hmask + 1) < xfrm_policy_hashmax &&
653 total > hmask)
654 return 1;
655
656 return 0;
657 }
658
xfrm_spd_getinfo(struct net * net,struct xfrmk_spdinfo * si)659 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
660 {
661 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
662 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
663 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
664 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
665 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
666 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
667 si->spdhcnt = net->xfrm.policy_idx_hmask;
668 si->spdhmcnt = xfrm_policy_hashmax;
669 }
670 EXPORT_SYMBOL(xfrm_spd_getinfo);
671
672 static DEFINE_MUTEX(hash_resize_mutex);
xfrm_hash_resize(struct work_struct * work)673 static void xfrm_hash_resize(struct work_struct *work)
674 {
675 struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
676 int dir, total;
677
678 mutex_lock(&hash_resize_mutex);
679
680 total = 0;
681 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
682 if (xfrm_bydst_should_resize(net, dir, &total))
683 xfrm_bydst_resize(net, dir);
684 }
685 if (xfrm_byidx_should_resize(net, total))
686 xfrm_byidx_resize(net, total);
687
688 mutex_unlock(&hash_resize_mutex);
689 }
690
691 /* Make sure *pol can be inserted into fastbin.
692 * Useful to check that later insert requests will be successful
693 * (provided xfrm_policy_lock is held throughout).
694 */
695 static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_alloc_bin(const struct xfrm_policy * pol,u8 dir)696 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
697 {
698 struct xfrm_pol_inexact_bin *bin, *prev;
699 struct xfrm_pol_inexact_key k = {
700 .family = pol->family,
701 .type = pol->type,
702 .dir = dir,
703 .if_id = pol->if_id,
704 };
705 struct net *net = xp_net(pol);
706
707 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
708
709 write_pnet(&k.net, net);
710 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
711 xfrm_pol_inexact_params);
712 if (bin)
713 return bin;
714
715 bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
716 if (!bin)
717 return NULL;
718
719 bin->k = k;
720 INIT_HLIST_HEAD(&bin->hhead);
721 bin->root_d = RB_ROOT;
722 bin->root_s = RB_ROOT;
723 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
724
725 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
726 &bin->k, &bin->head,
727 xfrm_pol_inexact_params);
728 if (!prev) {
729 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
730 return bin;
731 }
732
733 kfree(bin);
734
735 return IS_ERR(prev) ? NULL : prev;
736 }
737
xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t * addr,int family,u8 prefixlen)738 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
739 int family, u8 prefixlen)
740 {
741 if (xfrm_addr_any(addr, family))
742 return true;
743
744 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
745 return true;
746
747 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
748 return true;
749
750 return false;
751 }
752
753 static bool
xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy * policy)754 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
755 {
756 const xfrm_address_t *addr;
757 bool saddr_any, daddr_any;
758 u8 prefixlen;
759
760 addr = &policy->selector.saddr;
761 prefixlen = policy->selector.prefixlen_s;
762
763 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
764 policy->family,
765 prefixlen);
766 addr = &policy->selector.daddr;
767 prefixlen = policy->selector.prefixlen_d;
768 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
769 policy->family,
770 prefixlen);
771 return saddr_any && daddr_any;
772 }
773
xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node * node,const xfrm_address_t * addr,u8 prefixlen)774 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
775 const xfrm_address_t *addr, u8 prefixlen)
776 {
777 node->addr = *addr;
778 node->prefixlen = prefixlen;
779 }
780
781 static struct xfrm_pol_inexact_node *
xfrm_pol_inexact_node_alloc(const xfrm_address_t * addr,u8 prefixlen)782 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
783 {
784 struct xfrm_pol_inexact_node *node;
785
786 node = kzalloc(sizeof(*node), GFP_ATOMIC);
787 if (node)
788 xfrm_pol_inexact_node_init(node, addr, prefixlen);
789
790 return node;
791 }
792
xfrm_policy_addr_delta(const xfrm_address_t * a,const xfrm_address_t * b,u8 prefixlen,u16 family)793 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
794 const xfrm_address_t *b,
795 u8 prefixlen, u16 family)
796 {
797 u32 ma, mb, mask;
798 unsigned int pdw, pbi;
799 int delta = 0;
800
801 switch (family) {
802 case AF_INET:
803 if (prefixlen == 0)
804 return 0;
805 mask = ~0U << (32 - prefixlen);
806 ma = ntohl(a->a4) & mask;
807 mb = ntohl(b->a4) & mask;
808 if (ma < mb)
809 delta = -1;
810 else if (ma > mb)
811 delta = 1;
812 break;
813 case AF_INET6:
814 pdw = prefixlen >> 5;
815 pbi = prefixlen & 0x1f;
816
817 if (pdw) {
818 delta = memcmp(a->a6, b->a6, pdw << 2);
819 if (delta)
820 return delta;
821 }
822 if (pbi) {
823 mask = ~0U << (32 - pbi);
824 ma = ntohl(a->a6[pdw]) & mask;
825 mb = ntohl(b->a6[pdw]) & mask;
826 if (ma < mb)
827 delta = -1;
828 else if (ma > mb)
829 delta = 1;
830 }
831 break;
832 default:
833 break;
834 }
835
836 return delta;
837 }
838
xfrm_policy_inexact_list_reinsert(struct net * net,struct xfrm_pol_inexact_node * n,u16 family)839 static void xfrm_policy_inexact_list_reinsert(struct net *net,
840 struct xfrm_pol_inexact_node *n,
841 u16 family)
842 {
843 unsigned int matched_s, matched_d;
844 struct xfrm_policy *policy, *p;
845
846 matched_s = 0;
847 matched_d = 0;
848
849 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
850 struct hlist_node *newpos = NULL;
851 bool matches_s, matches_d;
852
853 if (!policy->bydst_reinsert)
854 continue;
855
856 WARN_ON_ONCE(policy->family != family);
857
858 policy->bydst_reinsert = false;
859 hlist_for_each_entry(p, &n->hhead, bydst) {
860 if (policy->priority > p->priority)
861 newpos = &p->bydst;
862 else if (policy->priority == p->priority &&
863 policy->pos > p->pos)
864 newpos = &p->bydst;
865 else
866 break;
867 }
868
869 if (newpos)
870 hlist_add_behind_rcu(&policy->bydst, newpos);
871 else
872 hlist_add_head_rcu(&policy->bydst, &n->hhead);
873
874 /* paranoia checks follow.
875 * Check that the reinserted policy matches at least
876 * saddr or daddr for current node prefix.
877 *
878 * Matching both is fine, matching saddr in one policy
879 * (but not daddr) and then matching only daddr in another
880 * is a bug.
881 */
882 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
883 &n->addr,
884 n->prefixlen,
885 family) == 0;
886 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
887 &n->addr,
888 n->prefixlen,
889 family) == 0;
890 if (matches_s && matches_d)
891 continue;
892
893 WARN_ON_ONCE(!matches_s && !matches_d);
894 if (matches_s)
895 matched_s++;
896 if (matches_d)
897 matched_d++;
898 WARN_ON_ONCE(matched_s && matched_d);
899 }
900 }
901
xfrm_policy_inexact_node_reinsert(struct net * net,struct xfrm_pol_inexact_node * n,struct rb_root * new,u16 family)902 static void xfrm_policy_inexact_node_reinsert(struct net *net,
903 struct xfrm_pol_inexact_node *n,
904 struct rb_root *new,
905 u16 family)
906 {
907 struct xfrm_pol_inexact_node *node;
908 struct rb_node **p, *parent;
909
910 /* we should not have another subtree here */
911 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
912 restart:
913 parent = NULL;
914 p = &new->rb_node;
915 while (*p) {
916 u8 prefixlen;
917 int delta;
918
919 parent = *p;
920 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
921
922 prefixlen = min(node->prefixlen, n->prefixlen);
923
924 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
925 prefixlen, family);
926 if (delta < 0) {
927 p = &parent->rb_left;
928 } else if (delta > 0) {
929 p = &parent->rb_right;
930 } else {
931 bool same_prefixlen = node->prefixlen == n->prefixlen;
932 struct xfrm_policy *tmp;
933
934 hlist_for_each_entry(tmp, &n->hhead, bydst) {
935 tmp->bydst_reinsert = true;
936 hlist_del_rcu(&tmp->bydst);
937 }
938
939 node->prefixlen = prefixlen;
940
941 xfrm_policy_inexact_list_reinsert(net, node, family);
942
943 if (same_prefixlen) {
944 kfree_rcu(n, rcu);
945 return;
946 }
947
948 rb_erase(*p, new);
949 kfree_rcu(n, rcu);
950 n = node;
951 goto restart;
952 }
953 }
954
955 rb_link_node_rcu(&n->node, parent, p);
956 rb_insert_color(&n->node, new);
957 }
958
959 /* merge nodes v and n */
xfrm_policy_inexact_node_merge(struct net * net,struct xfrm_pol_inexact_node * v,struct xfrm_pol_inexact_node * n,u16 family)960 static void xfrm_policy_inexact_node_merge(struct net *net,
961 struct xfrm_pol_inexact_node *v,
962 struct xfrm_pol_inexact_node *n,
963 u16 family)
964 {
965 struct xfrm_pol_inexact_node *node;
966 struct xfrm_policy *tmp;
967 struct rb_node *rnode;
968
969 /* To-be-merged node v has a subtree.
970 *
971 * Dismantle it and insert its nodes to n->root.
972 */
973 while ((rnode = rb_first(&v->root)) != NULL) {
974 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
975 rb_erase(&node->node, &v->root);
976 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
977 family);
978 }
979
980 hlist_for_each_entry(tmp, &v->hhead, bydst) {
981 tmp->bydst_reinsert = true;
982 hlist_del_rcu(&tmp->bydst);
983 }
984
985 xfrm_policy_inexact_list_reinsert(net, n, family);
986 }
987
988 static struct xfrm_pol_inexact_node *
xfrm_policy_inexact_insert_node(struct net * net,struct rb_root * root,xfrm_address_t * addr,u16 family,u8 prefixlen,u8 dir)989 xfrm_policy_inexact_insert_node(struct net *net,
990 struct rb_root *root,
991 xfrm_address_t *addr,
992 u16 family, u8 prefixlen, u8 dir)
993 {
994 struct xfrm_pol_inexact_node *cached = NULL;
995 struct rb_node **p, *parent = NULL;
996 struct xfrm_pol_inexact_node *node;
997
998 p = &root->rb_node;
999 while (*p) {
1000 int delta;
1001
1002 parent = *p;
1003 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
1004
1005 delta = xfrm_policy_addr_delta(addr, &node->addr,
1006 node->prefixlen,
1007 family);
1008 if (delta == 0 && prefixlen >= node->prefixlen) {
1009 WARN_ON_ONCE(cached); /* ipsec policies got lost */
1010 return node;
1011 }
1012
1013 if (delta < 0)
1014 p = &parent->rb_left;
1015 else
1016 p = &parent->rb_right;
1017
1018 if (prefixlen < node->prefixlen) {
1019 delta = xfrm_policy_addr_delta(addr, &node->addr,
1020 prefixlen,
1021 family);
1022 if (delta)
1023 continue;
1024
1025 /* This node is a subnet of the new prefix. It needs
1026 * to be removed and re-inserted with the smaller
1027 * prefix and all nodes that are now also covered
1028 * by the reduced prefixlen.
1029 */
1030 rb_erase(&node->node, root);
1031
1032 if (!cached) {
1033 xfrm_pol_inexact_node_init(node, addr,
1034 prefixlen);
1035 cached = node;
1036 } else {
1037 /* This node also falls within the new
1038 * prefixlen. Merge the to-be-reinserted
1039 * node and this one.
1040 */
1041 xfrm_policy_inexact_node_merge(net, node,
1042 cached, family);
1043 kfree_rcu(node, rcu);
1044 }
1045
1046 /* restart */
1047 p = &root->rb_node;
1048 parent = NULL;
1049 }
1050 }
1051
1052 node = cached;
1053 if (!node) {
1054 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1055 if (!node)
1056 return NULL;
1057 }
1058
1059 rb_link_node_rcu(&node->node, parent, p);
1060 rb_insert_color(&node->node, root);
1061
1062 return node;
1063 }
1064
xfrm_policy_inexact_gc_tree(struct rb_root * r,bool rm)1065 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1066 {
1067 struct xfrm_pol_inexact_node *node;
1068 struct rb_node *rn = rb_first(r);
1069
1070 while (rn) {
1071 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1072
1073 xfrm_policy_inexact_gc_tree(&node->root, rm);
1074 rn = rb_next(rn);
1075
1076 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1077 WARN_ON_ONCE(rm);
1078 continue;
1079 }
1080
1081 rb_erase(&node->node, r);
1082 kfree_rcu(node, rcu);
1083 }
1084 }
1085
__xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin * b,bool net_exit)1086 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1087 {
1088 write_seqcount_begin(&b->count);
1089 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1090 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1091 write_seqcount_end(&b->count);
1092
1093 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1094 !hlist_empty(&b->hhead)) {
1095 WARN_ON_ONCE(net_exit);
1096 return;
1097 }
1098
1099 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1100 xfrm_pol_inexact_params) == 0) {
1101 list_del(&b->inexact_bins);
1102 kfree_rcu(b, rcu);
1103 }
1104 }
1105
xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin * b)1106 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1107 {
1108 struct net *net = read_pnet(&b->k.net);
1109
1110 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1111 __xfrm_policy_inexact_prune_bin(b, false);
1112 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1113 }
1114
__xfrm_policy_inexact_flush(struct net * net)1115 static void __xfrm_policy_inexact_flush(struct net *net)
1116 {
1117 struct xfrm_pol_inexact_bin *bin, *t;
1118
1119 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1120
1121 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1122 __xfrm_policy_inexact_prune_bin(bin, false);
1123 }
1124
1125 static struct hlist_head *
xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin * bin,struct xfrm_policy * policy,u8 dir)1126 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1127 struct xfrm_policy *policy, u8 dir)
1128 {
1129 struct xfrm_pol_inexact_node *n;
1130 struct net *net;
1131
1132 net = xp_net(policy);
1133 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1134
1135 if (xfrm_policy_inexact_insert_use_any_list(policy))
1136 return &bin->hhead;
1137
1138 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1139 policy->family,
1140 policy->selector.prefixlen_d)) {
1141 write_seqcount_begin(&bin->count);
1142 n = xfrm_policy_inexact_insert_node(net,
1143 &bin->root_s,
1144 &policy->selector.saddr,
1145 policy->family,
1146 policy->selector.prefixlen_s,
1147 dir);
1148 write_seqcount_end(&bin->count);
1149 if (!n)
1150 return NULL;
1151
1152 return &n->hhead;
1153 }
1154
1155 /* daddr is fixed */
1156 write_seqcount_begin(&bin->count);
1157 n = xfrm_policy_inexact_insert_node(net,
1158 &bin->root_d,
1159 &policy->selector.daddr,
1160 policy->family,
1161 policy->selector.prefixlen_d, dir);
1162 write_seqcount_end(&bin->count);
1163 if (!n)
1164 return NULL;
1165
1166 /* saddr is wildcard */
1167 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1168 policy->family,
1169 policy->selector.prefixlen_s))
1170 return &n->hhead;
1171
1172 write_seqcount_begin(&bin->count);
1173 n = xfrm_policy_inexact_insert_node(net,
1174 &n->root,
1175 &policy->selector.saddr,
1176 policy->family,
1177 policy->selector.prefixlen_s, dir);
1178 write_seqcount_end(&bin->count);
1179 if (!n)
1180 return NULL;
1181
1182 return &n->hhead;
1183 }
1184
1185 static struct xfrm_policy *
xfrm_policy_inexact_insert(struct xfrm_policy * policy,u8 dir,int excl)1186 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1187 {
1188 struct xfrm_pol_inexact_bin *bin;
1189 struct xfrm_policy *delpol;
1190 struct hlist_head *chain;
1191 struct net *net;
1192
1193 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1194 if (!bin)
1195 return ERR_PTR(-ENOMEM);
1196
1197 net = xp_net(policy);
1198 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1199
1200 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1201 if (!chain) {
1202 __xfrm_policy_inexact_prune_bin(bin, false);
1203 return ERR_PTR(-ENOMEM);
1204 }
1205
1206 delpol = xfrm_policy_insert_list(chain, policy, excl);
1207 if (delpol && excl) {
1208 __xfrm_policy_inexact_prune_bin(bin, false);
1209 return ERR_PTR(-EEXIST);
1210 }
1211
1212 chain = &net->xfrm.policy_inexact[dir];
1213 xfrm_policy_insert_inexact_list(chain, policy);
1214
1215 if (delpol)
1216 __xfrm_policy_inexact_prune_bin(bin, false);
1217
1218 return delpol;
1219 }
1220
xfrm_hash_rebuild(struct work_struct * work)1221 static void xfrm_hash_rebuild(struct work_struct *work)
1222 {
1223 struct net *net = container_of(work, struct net,
1224 xfrm.policy_hthresh.work);
1225 unsigned int hmask;
1226 struct xfrm_policy *pol;
1227 struct xfrm_policy *policy;
1228 struct hlist_head *chain;
1229 struct hlist_head *odst;
1230 struct hlist_node *newpos;
1231 int i;
1232 int dir;
1233 unsigned seq;
1234 u8 lbits4, rbits4, lbits6, rbits6;
1235
1236 mutex_lock(&hash_resize_mutex);
1237
1238 /* read selector prefixlen thresholds */
1239 do {
1240 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1241
1242 lbits4 = net->xfrm.policy_hthresh.lbits4;
1243 rbits4 = net->xfrm.policy_hthresh.rbits4;
1244 lbits6 = net->xfrm.policy_hthresh.lbits6;
1245 rbits6 = net->xfrm.policy_hthresh.rbits6;
1246 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1247
1248 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1249 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
1250
1251 /* make sure that we can insert the indirect policies again before
1252 * we start with destructive action.
1253 */
1254 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1255 struct xfrm_pol_inexact_bin *bin;
1256 u8 dbits, sbits;
1257
1258 dir = xfrm_policy_id2dir(policy->index);
1259 if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1260 continue;
1261
1262 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1263 if (policy->family == AF_INET) {
1264 dbits = rbits4;
1265 sbits = lbits4;
1266 } else {
1267 dbits = rbits6;
1268 sbits = lbits6;
1269 }
1270 } else {
1271 if (policy->family == AF_INET) {
1272 dbits = lbits4;
1273 sbits = rbits4;
1274 } else {
1275 dbits = lbits6;
1276 sbits = rbits6;
1277 }
1278 }
1279
1280 if (policy->selector.prefixlen_d < dbits ||
1281 policy->selector.prefixlen_s < sbits)
1282 continue;
1283
1284 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1285 if (!bin)
1286 goto out_unlock;
1287
1288 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1289 goto out_unlock;
1290 }
1291
1292 /* reset the bydst and inexact table in all directions */
1293 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1294 struct hlist_node *n;
1295
1296 hlist_for_each_entry_safe(policy, n,
1297 &net->xfrm.policy_inexact[dir],
1298 bydst_inexact_list) {
1299 hlist_del_rcu(&policy->bydst);
1300 hlist_del_init(&policy->bydst_inexact_list);
1301 }
1302
1303 hmask = net->xfrm.policy_bydst[dir].hmask;
1304 odst = net->xfrm.policy_bydst[dir].table;
1305 for (i = hmask; i >= 0; i--) {
1306 hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1307 hlist_del_rcu(&policy->bydst);
1308 }
1309 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1310 /* dir out => dst = remote, src = local */
1311 net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1312 net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1313 net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1314 net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1315 } else {
1316 /* dir in/fwd => dst = local, src = remote */
1317 net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1318 net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1319 net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1320 net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1321 }
1322 }
1323
1324 /* re-insert all policies by order of creation */
1325 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1326 if (policy->walk.dead)
1327 continue;
1328 dir = xfrm_policy_id2dir(policy->index);
1329 if (dir >= XFRM_POLICY_MAX) {
1330 /* skip socket policies */
1331 continue;
1332 }
1333 newpos = NULL;
1334 chain = policy_hash_bysel(net, &policy->selector,
1335 policy->family, dir);
1336
1337 if (!chain) {
1338 void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1339
1340 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1341 continue;
1342 }
1343
1344 hlist_for_each_entry(pol, chain, bydst) {
1345 if (policy->priority >= pol->priority)
1346 newpos = &pol->bydst;
1347 else
1348 break;
1349 }
1350 if (newpos)
1351 hlist_add_behind_rcu(&policy->bydst, newpos);
1352 else
1353 hlist_add_head_rcu(&policy->bydst, chain);
1354 }
1355
1356 out_unlock:
1357 __xfrm_policy_inexact_flush(net);
1358 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1359 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1360
1361 mutex_unlock(&hash_resize_mutex);
1362 }
1363
xfrm_policy_hash_rebuild(struct net * net)1364 void xfrm_policy_hash_rebuild(struct net *net)
1365 {
1366 schedule_work(&net->xfrm.policy_hthresh.work);
1367 }
1368 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1369
1370 /* Generate new index... KAME seems to generate them ordered by cost
1371 * of an absolute inpredictability of ordering of rules. This will not pass. */
xfrm_gen_index(struct net * net,int dir,u32 index)1372 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1373 {
1374 static u32 idx_generator;
1375
1376 for (;;) {
1377 struct hlist_head *list;
1378 struct xfrm_policy *p;
1379 u32 idx;
1380 int found;
1381
1382 if (!index) {
1383 idx = (idx_generator | dir);
1384 idx_generator += 8;
1385 } else {
1386 idx = index;
1387 index = 0;
1388 }
1389
1390 if (idx == 0)
1391 idx = 8;
1392 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1393 found = 0;
1394 hlist_for_each_entry(p, list, byidx) {
1395 if (p->index == idx) {
1396 found = 1;
1397 break;
1398 }
1399 }
1400 if (!found)
1401 return idx;
1402 }
1403 }
1404
selector_cmp(struct xfrm_selector * s1,struct xfrm_selector * s2)1405 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1406 {
1407 u32 *p1 = (u32 *) s1;
1408 u32 *p2 = (u32 *) s2;
1409 int len = sizeof(struct xfrm_selector) / sizeof(u32);
1410 int i;
1411
1412 for (i = 0; i < len; i++) {
1413 if (p1[i] != p2[i])
1414 return 1;
1415 }
1416
1417 return 0;
1418 }
1419
xfrm_policy_requeue(struct xfrm_policy * old,struct xfrm_policy * new)1420 static void xfrm_policy_requeue(struct xfrm_policy *old,
1421 struct xfrm_policy *new)
1422 {
1423 struct xfrm_policy_queue *pq = &old->polq;
1424 struct sk_buff_head list;
1425
1426 if (skb_queue_empty(&pq->hold_queue))
1427 return;
1428
1429 __skb_queue_head_init(&list);
1430
1431 spin_lock_bh(&pq->hold_queue.lock);
1432 skb_queue_splice_init(&pq->hold_queue, &list);
1433 if (del_timer(&pq->hold_timer))
1434 xfrm_pol_put(old);
1435 spin_unlock_bh(&pq->hold_queue.lock);
1436
1437 pq = &new->polq;
1438
1439 spin_lock_bh(&pq->hold_queue.lock);
1440 skb_queue_splice(&list, &pq->hold_queue);
1441 pq->timeout = XFRM_QUEUE_TMO_MIN;
1442 if (!mod_timer(&pq->hold_timer, jiffies))
1443 xfrm_pol_hold(new);
1444 spin_unlock_bh(&pq->hold_queue.lock);
1445 }
1446
xfrm_policy_mark_match(const struct xfrm_mark * mark,struct xfrm_policy * pol)1447 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1448 struct xfrm_policy *pol)
1449 {
1450 return mark->v == pol->mark.v && mark->m == pol->mark.m;
1451 }
1452
xfrm_pol_bin_key(const void * data,u32 len,u32 seed)1453 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1454 {
1455 const struct xfrm_pol_inexact_key *k = data;
1456 u32 a = k->type << 24 | k->dir << 16 | k->family;
1457
1458 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1459 seed);
1460 }
1461
xfrm_pol_bin_obj(const void * data,u32 len,u32 seed)1462 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1463 {
1464 const struct xfrm_pol_inexact_bin *b = data;
1465
1466 return xfrm_pol_bin_key(&b->k, 0, seed);
1467 }
1468
xfrm_pol_bin_cmp(struct rhashtable_compare_arg * arg,const void * ptr)1469 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1470 const void *ptr)
1471 {
1472 const struct xfrm_pol_inexact_key *key = arg->key;
1473 const struct xfrm_pol_inexact_bin *b = ptr;
1474 int ret;
1475
1476 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1477 return -1;
1478
1479 ret = b->k.dir ^ key->dir;
1480 if (ret)
1481 return ret;
1482
1483 ret = b->k.type ^ key->type;
1484 if (ret)
1485 return ret;
1486
1487 ret = b->k.family ^ key->family;
1488 if (ret)
1489 return ret;
1490
1491 return b->k.if_id ^ key->if_id;
1492 }
1493
1494 static const struct rhashtable_params xfrm_pol_inexact_params = {
1495 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head),
1496 .hashfn = xfrm_pol_bin_key,
1497 .obj_hashfn = xfrm_pol_bin_obj,
1498 .obj_cmpfn = xfrm_pol_bin_cmp,
1499 .automatic_shrinking = true,
1500 };
1501
xfrm_policy_insert_inexact_list(struct hlist_head * chain,struct xfrm_policy * policy)1502 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1503 struct xfrm_policy *policy)
1504 {
1505 struct xfrm_policy *pol, *delpol = NULL;
1506 struct hlist_node *newpos = NULL;
1507 int i = 0;
1508
1509 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1510 if (pol->type == policy->type &&
1511 pol->if_id == policy->if_id &&
1512 !selector_cmp(&pol->selector, &policy->selector) &&
1513 xfrm_policy_mark_match(&policy->mark, pol) &&
1514 xfrm_sec_ctx_match(pol->security, policy->security) &&
1515 !WARN_ON(delpol)) {
1516 delpol = pol;
1517 if (policy->priority > pol->priority)
1518 continue;
1519 } else if (policy->priority >= pol->priority) {
1520 newpos = &pol->bydst_inexact_list;
1521 continue;
1522 }
1523 if (delpol)
1524 break;
1525 }
1526
1527 if (newpos)
1528 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1529 else
1530 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1531
1532 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1533 pol->pos = i;
1534 i++;
1535 }
1536 }
1537
xfrm_policy_insert_list(struct hlist_head * chain,struct xfrm_policy * policy,bool excl)1538 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1539 struct xfrm_policy *policy,
1540 bool excl)
1541 {
1542 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1543
1544 hlist_for_each_entry(pol, chain, bydst) {
1545 if (pol->type == policy->type &&
1546 pol->if_id == policy->if_id &&
1547 !selector_cmp(&pol->selector, &policy->selector) &&
1548 xfrm_policy_mark_match(&policy->mark, pol) &&
1549 xfrm_sec_ctx_match(pol->security, policy->security) &&
1550 !WARN_ON(delpol)) {
1551 if (excl)
1552 return ERR_PTR(-EEXIST);
1553 delpol = pol;
1554 if (policy->priority > pol->priority)
1555 continue;
1556 } else if (policy->priority >= pol->priority) {
1557 newpos = pol;
1558 continue;
1559 }
1560 if (delpol)
1561 break;
1562 }
1563
1564 if (newpos)
1565 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1566 else
1567 hlist_add_head_rcu(&policy->bydst, chain);
1568
1569 return delpol;
1570 }
1571
xfrm_policy_insert(int dir,struct xfrm_policy * policy,int excl)1572 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1573 {
1574 struct net *net = xp_net(policy);
1575 struct xfrm_policy *delpol;
1576 struct hlist_head *chain;
1577
1578 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1579 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1580 if (chain)
1581 delpol = xfrm_policy_insert_list(chain, policy, excl);
1582 else
1583 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1584
1585 if (IS_ERR(delpol)) {
1586 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1587 return PTR_ERR(delpol);
1588 }
1589
1590 __xfrm_policy_link(policy, dir);
1591
1592 /* After previous checking, family can either be AF_INET or AF_INET6 */
1593 if (policy->family == AF_INET)
1594 rt_genid_bump_ipv4(net);
1595 else
1596 rt_genid_bump_ipv6(net);
1597
1598 if (delpol) {
1599 xfrm_policy_requeue(delpol, policy);
1600 __xfrm_policy_unlink(delpol, dir);
1601 }
1602 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1603 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1604 policy->curlft.add_time = ktime_get_real_seconds();
1605 policy->curlft.use_time = 0;
1606 if (!mod_timer(&policy->timer, jiffies + HZ))
1607 xfrm_pol_hold(policy);
1608 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1609
1610 if (delpol)
1611 xfrm_policy_kill(delpol);
1612 else if (xfrm_bydst_should_resize(net, dir, NULL))
1613 schedule_work(&net->xfrm.policy_hash_work);
1614
1615 return 0;
1616 }
1617 EXPORT_SYMBOL(xfrm_policy_insert);
1618
1619 static struct xfrm_policy *
__xfrm_policy_bysel_ctx(struct hlist_head * chain,const struct xfrm_mark * mark,u32 if_id,u8 type,int dir,struct xfrm_selector * sel,struct xfrm_sec_ctx * ctx)1620 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1621 u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1622 struct xfrm_sec_ctx *ctx)
1623 {
1624 struct xfrm_policy *pol;
1625
1626 if (!chain)
1627 return NULL;
1628
1629 hlist_for_each_entry(pol, chain, bydst) {
1630 if (pol->type == type &&
1631 pol->if_id == if_id &&
1632 xfrm_policy_mark_match(mark, pol) &&
1633 !selector_cmp(sel, &pol->selector) &&
1634 xfrm_sec_ctx_match(ctx, pol->security))
1635 return pol;
1636 }
1637
1638 return NULL;
1639 }
1640
1641 struct xfrm_policy *
xfrm_policy_bysel_ctx(struct net * net,const struct xfrm_mark * mark,u32 if_id,u8 type,int dir,struct xfrm_selector * sel,struct xfrm_sec_ctx * ctx,int delete,int * err)1642 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1643 u8 type, int dir, struct xfrm_selector *sel,
1644 struct xfrm_sec_ctx *ctx, int delete, int *err)
1645 {
1646 struct xfrm_pol_inexact_bin *bin = NULL;
1647 struct xfrm_policy *pol, *ret = NULL;
1648 struct hlist_head *chain;
1649
1650 *err = 0;
1651 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1652 chain = policy_hash_bysel(net, sel, sel->family, dir);
1653 if (!chain) {
1654 struct xfrm_pol_inexact_candidates cand;
1655 int i;
1656
1657 bin = xfrm_policy_inexact_lookup(net, type,
1658 sel->family, dir, if_id);
1659 if (!bin) {
1660 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1661 return NULL;
1662 }
1663
1664 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1665 &sel->saddr,
1666 &sel->daddr)) {
1667 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1668 return NULL;
1669 }
1670
1671 pol = NULL;
1672 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1673 struct xfrm_policy *tmp;
1674
1675 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1676 if_id, type, dir,
1677 sel, ctx);
1678 if (!tmp)
1679 continue;
1680
1681 if (!pol || tmp->pos < pol->pos)
1682 pol = tmp;
1683 }
1684 } else {
1685 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1686 sel, ctx);
1687 }
1688
1689 if (pol) {
1690 xfrm_pol_hold(pol);
1691 if (delete) {
1692 *err = security_xfrm_policy_delete(pol->security);
1693 if (*err) {
1694 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1695 return pol;
1696 }
1697 __xfrm_policy_unlink(pol, dir);
1698 }
1699 ret = pol;
1700 }
1701 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1702
1703 if (ret && delete)
1704 xfrm_policy_kill(ret);
1705 if (bin && delete)
1706 xfrm_policy_inexact_prune_bin(bin);
1707 return ret;
1708 }
1709 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1710
1711 struct xfrm_policy *
xfrm_policy_byid(struct net * net,const struct xfrm_mark * mark,u32 if_id,u8 type,int dir,u32 id,int delete,int * err)1712 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1713 u8 type, int dir, u32 id, int delete, int *err)
1714 {
1715 struct xfrm_policy *pol, *ret;
1716 struct hlist_head *chain;
1717
1718 *err = -ENOENT;
1719 if (xfrm_policy_id2dir(id) != dir)
1720 return NULL;
1721
1722 *err = 0;
1723 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1724 chain = net->xfrm.policy_byidx + idx_hash(net, id);
1725 ret = NULL;
1726 hlist_for_each_entry(pol, chain, byidx) {
1727 if (pol->type == type && pol->index == id &&
1728 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1729 xfrm_pol_hold(pol);
1730 if (delete) {
1731 *err = security_xfrm_policy_delete(
1732 pol->security);
1733 if (*err) {
1734 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1735 return pol;
1736 }
1737 __xfrm_policy_unlink(pol, dir);
1738 }
1739 ret = pol;
1740 break;
1741 }
1742 }
1743 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1744
1745 if (ret && delete)
1746 xfrm_policy_kill(ret);
1747 return ret;
1748 }
1749 EXPORT_SYMBOL(xfrm_policy_byid);
1750
1751 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1752 static inline int
xfrm_policy_flush_secctx_check(struct net * net,u8 type,bool task_valid)1753 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1754 {
1755 struct xfrm_policy *pol;
1756 int err = 0;
1757
1758 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1759 if (pol->walk.dead ||
1760 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1761 pol->type != type)
1762 continue;
1763
1764 err = security_xfrm_policy_delete(pol->security);
1765 if (err) {
1766 xfrm_audit_policy_delete(pol, 0, task_valid);
1767 return err;
1768 }
1769 }
1770 return err;
1771 }
1772 #else
1773 static inline int
xfrm_policy_flush_secctx_check(struct net * net,u8 type,bool task_valid)1774 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1775 {
1776 return 0;
1777 }
1778 #endif
1779
xfrm_policy_flush(struct net * net,u8 type,bool task_valid)1780 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1781 {
1782 int dir, err = 0, cnt = 0;
1783 struct xfrm_policy *pol;
1784
1785 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1786
1787 err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1788 if (err)
1789 goto out;
1790
1791 again:
1792 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1793 dir = xfrm_policy_id2dir(pol->index);
1794 if (pol->walk.dead ||
1795 dir >= XFRM_POLICY_MAX ||
1796 pol->type != type)
1797 continue;
1798
1799 __xfrm_policy_unlink(pol, dir);
1800 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1801 cnt++;
1802 xfrm_audit_policy_delete(pol, 1, task_valid);
1803 xfrm_policy_kill(pol);
1804 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1805 goto again;
1806 }
1807 if (cnt)
1808 __xfrm_policy_inexact_flush(net);
1809 else
1810 err = -ESRCH;
1811 out:
1812 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1813 return err;
1814 }
1815 EXPORT_SYMBOL(xfrm_policy_flush);
1816
xfrm_policy_walk(struct net * net,struct xfrm_policy_walk * walk,int (* func)(struct xfrm_policy *,int,int,void *),void * data)1817 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1818 int (*func)(struct xfrm_policy *, int, int, void*),
1819 void *data)
1820 {
1821 struct xfrm_policy *pol;
1822 struct xfrm_policy_walk_entry *x;
1823 int error = 0;
1824
1825 if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1826 walk->type != XFRM_POLICY_TYPE_ANY)
1827 return -EINVAL;
1828
1829 if (list_empty(&walk->walk.all) && walk->seq != 0)
1830 return 0;
1831
1832 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1833 if (list_empty(&walk->walk.all))
1834 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1835 else
1836 x = list_first_entry(&walk->walk.all,
1837 struct xfrm_policy_walk_entry, all);
1838
1839 list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1840 if (x->dead)
1841 continue;
1842 pol = container_of(x, struct xfrm_policy, walk);
1843 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1844 walk->type != pol->type)
1845 continue;
1846 error = func(pol, xfrm_policy_id2dir(pol->index),
1847 walk->seq, data);
1848 if (error) {
1849 list_move_tail(&walk->walk.all, &x->all);
1850 goto out;
1851 }
1852 walk->seq++;
1853 }
1854 if (walk->seq == 0) {
1855 error = -ENOENT;
1856 goto out;
1857 }
1858 list_del_init(&walk->walk.all);
1859 out:
1860 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1861 return error;
1862 }
1863 EXPORT_SYMBOL(xfrm_policy_walk);
1864
xfrm_policy_walk_init(struct xfrm_policy_walk * walk,u8 type)1865 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1866 {
1867 INIT_LIST_HEAD(&walk->walk.all);
1868 walk->walk.dead = 1;
1869 walk->type = type;
1870 walk->seq = 0;
1871 }
1872 EXPORT_SYMBOL(xfrm_policy_walk_init);
1873
xfrm_policy_walk_done(struct xfrm_policy_walk * walk,struct net * net)1874 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1875 {
1876 if (list_empty(&walk->walk.all))
1877 return;
1878
1879 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1880 list_del(&walk->walk.all);
1881 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1882 }
1883 EXPORT_SYMBOL(xfrm_policy_walk_done);
1884
1885 /*
1886 * Find policy to apply to this flow.
1887 *
1888 * Returns 0 if policy found, else an -errno.
1889 */
xfrm_policy_match(const struct xfrm_policy * pol,const struct flowi * fl,u8 type,u16 family,u32 if_id)1890 static int xfrm_policy_match(const struct xfrm_policy *pol,
1891 const struct flowi *fl,
1892 u8 type, u16 family, u32 if_id)
1893 {
1894 const struct xfrm_selector *sel = &pol->selector;
1895 int ret = -ESRCH;
1896 bool match;
1897
1898 if (pol->family != family ||
1899 pol->if_id != if_id ||
1900 (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1901 pol->type != type)
1902 return ret;
1903
1904 match = xfrm_selector_match(sel, fl, family);
1905 if (match)
1906 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
1907 return ret;
1908 }
1909
1910 static struct xfrm_pol_inexact_node *
xfrm_policy_lookup_inexact_addr(const struct rb_root * r,seqcount_spinlock_t * count,const xfrm_address_t * addr,u16 family)1911 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1912 seqcount_spinlock_t *count,
1913 const xfrm_address_t *addr, u16 family)
1914 {
1915 const struct rb_node *parent;
1916 int seq;
1917
1918 again:
1919 seq = read_seqcount_begin(count);
1920
1921 parent = rcu_dereference_raw(r->rb_node);
1922 while (parent) {
1923 struct xfrm_pol_inexact_node *node;
1924 int delta;
1925
1926 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
1927
1928 delta = xfrm_policy_addr_delta(addr, &node->addr,
1929 node->prefixlen, family);
1930 if (delta < 0) {
1931 parent = rcu_dereference_raw(parent->rb_left);
1932 continue;
1933 } else if (delta > 0) {
1934 parent = rcu_dereference_raw(parent->rb_right);
1935 continue;
1936 }
1937
1938 return node;
1939 }
1940
1941 if (read_seqcount_retry(count, seq))
1942 goto again;
1943
1944 return NULL;
1945 }
1946
1947 static bool
xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates * cand,struct xfrm_pol_inexact_bin * b,const xfrm_address_t * saddr,const xfrm_address_t * daddr)1948 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
1949 struct xfrm_pol_inexact_bin *b,
1950 const xfrm_address_t *saddr,
1951 const xfrm_address_t *daddr)
1952 {
1953 struct xfrm_pol_inexact_node *n;
1954 u16 family;
1955
1956 if (!b)
1957 return false;
1958
1959 family = b->k.family;
1960 memset(cand, 0, sizeof(*cand));
1961 cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
1962
1963 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
1964 family);
1965 if (n) {
1966 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
1967 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
1968 family);
1969 if (n)
1970 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
1971 }
1972
1973 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
1974 family);
1975 if (n)
1976 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
1977
1978 return true;
1979 }
1980
1981 static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_lookup_rcu(struct net * net,u8 type,u16 family,u8 dir,u32 if_id)1982 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
1983 u8 dir, u32 if_id)
1984 {
1985 struct xfrm_pol_inexact_key k = {
1986 .family = family,
1987 .type = type,
1988 .dir = dir,
1989 .if_id = if_id,
1990 };
1991
1992 write_pnet(&k.net, net);
1993
1994 return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
1995 xfrm_pol_inexact_params);
1996 }
1997
1998 static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_lookup(struct net * net,u8 type,u16 family,u8 dir,u32 if_id)1999 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2000 u8 dir, u32 if_id)
2001 {
2002 struct xfrm_pol_inexact_bin *bin;
2003
2004 lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2005
2006 rcu_read_lock();
2007 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2008 rcu_read_unlock();
2009
2010 return bin;
2011 }
2012
2013 static struct xfrm_policy *
__xfrm_policy_eval_candidates(struct hlist_head * chain,struct xfrm_policy * prefer,const struct flowi * fl,u8 type,u16 family,u32 if_id)2014 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2015 struct xfrm_policy *prefer,
2016 const struct flowi *fl,
2017 u8 type, u16 family, u32 if_id)
2018 {
2019 u32 priority = prefer ? prefer->priority : ~0u;
2020 struct xfrm_policy *pol;
2021
2022 if (!chain)
2023 return NULL;
2024
2025 hlist_for_each_entry_rcu(pol, chain, bydst) {
2026 int err;
2027
2028 if (pol->priority > priority)
2029 break;
2030
2031 err = xfrm_policy_match(pol, fl, type, family, if_id);
2032 if (err) {
2033 if (err != -ESRCH)
2034 return ERR_PTR(err);
2035
2036 continue;
2037 }
2038
2039 if (prefer) {
2040 /* matches. Is it older than *prefer? */
2041 if (pol->priority == priority &&
2042 prefer->pos < pol->pos)
2043 return prefer;
2044 }
2045
2046 return pol;
2047 }
2048
2049 return NULL;
2050 }
2051
2052 static struct xfrm_policy *
xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates * cand,struct xfrm_policy * prefer,const struct flowi * fl,u8 type,u16 family,u32 if_id)2053 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2054 struct xfrm_policy *prefer,
2055 const struct flowi *fl,
2056 u8 type, u16 family, u32 if_id)
2057 {
2058 struct xfrm_policy *tmp;
2059 int i;
2060
2061 for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2062 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2063 prefer,
2064 fl, type, family, if_id);
2065 if (!tmp)
2066 continue;
2067
2068 if (IS_ERR(tmp))
2069 return tmp;
2070 prefer = tmp;
2071 }
2072
2073 return prefer;
2074 }
2075
xfrm_policy_lookup_bytype(struct net * net,u8 type,const struct flowi * fl,u16 family,u8 dir,u32 if_id)2076 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2077 const struct flowi *fl,
2078 u16 family, u8 dir,
2079 u32 if_id)
2080 {
2081 struct xfrm_pol_inexact_candidates cand;
2082 const xfrm_address_t *daddr, *saddr;
2083 struct xfrm_pol_inexact_bin *bin;
2084 struct xfrm_policy *pol, *ret;
2085 struct hlist_head *chain;
2086 unsigned int sequence;
2087 int err;
2088
2089 daddr = xfrm_flowi_daddr(fl, family);
2090 saddr = xfrm_flowi_saddr(fl, family);
2091 if (unlikely(!daddr || !saddr))
2092 return NULL;
2093
2094 rcu_read_lock();
2095 retry:
2096 do {
2097 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2098 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2099 } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2100
2101 ret = NULL;
2102 hlist_for_each_entry_rcu(pol, chain, bydst) {
2103 err = xfrm_policy_match(pol, fl, type, family, if_id);
2104 if (err) {
2105 if (err == -ESRCH)
2106 continue;
2107 else {
2108 ret = ERR_PTR(err);
2109 goto fail;
2110 }
2111 } else {
2112 ret = pol;
2113 break;
2114 }
2115 }
2116 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2117 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2118 daddr))
2119 goto skip_inexact;
2120
2121 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2122 family, if_id);
2123 if (pol) {
2124 ret = pol;
2125 if (IS_ERR(pol))
2126 goto fail;
2127 }
2128
2129 skip_inexact:
2130 if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2131 goto retry;
2132
2133 if (ret && !xfrm_pol_hold_rcu(ret))
2134 goto retry;
2135 fail:
2136 rcu_read_unlock();
2137
2138 return ret;
2139 }
2140
xfrm_policy_lookup(struct net * net,const struct flowi * fl,u16 family,u8 dir,u32 if_id)2141 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2142 const struct flowi *fl,
2143 u16 family, u8 dir, u32 if_id)
2144 {
2145 #ifdef CONFIG_XFRM_SUB_POLICY
2146 struct xfrm_policy *pol;
2147
2148 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2149 dir, if_id);
2150 if (pol != NULL)
2151 return pol;
2152 #endif
2153 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2154 dir, if_id);
2155 }
2156
xfrm_sk_policy_lookup(const struct sock * sk,int dir,const struct flowi * fl,u16 family,u32 if_id)2157 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2158 const struct flowi *fl,
2159 u16 family, u32 if_id)
2160 {
2161 struct xfrm_policy *pol;
2162
2163 rcu_read_lock();
2164 again:
2165 pol = rcu_dereference(sk->sk_policy[dir]);
2166 if (pol != NULL) {
2167 bool match;
2168 int err = 0;
2169
2170 if (pol->family != family) {
2171 pol = NULL;
2172 goto out;
2173 }
2174
2175 match = xfrm_selector_match(&pol->selector, fl, family);
2176 if (match) {
2177 if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
2178 pol->if_id != if_id) {
2179 pol = NULL;
2180 goto out;
2181 }
2182 err = security_xfrm_policy_lookup(pol->security,
2183 fl->flowi_secid);
2184 if (!err) {
2185 if (!xfrm_pol_hold_rcu(pol))
2186 goto again;
2187 } else if (err == -ESRCH) {
2188 pol = NULL;
2189 } else {
2190 pol = ERR_PTR(err);
2191 }
2192 } else
2193 pol = NULL;
2194 }
2195 out:
2196 rcu_read_unlock();
2197 return pol;
2198 }
2199
__xfrm_policy_link(struct xfrm_policy * pol,int dir)2200 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2201 {
2202 struct net *net = xp_net(pol);
2203
2204 list_add(&pol->walk.all, &net->xfrm.policy_all);
2205 net->xfrm.policy_count[dir]++;
2206 xfrm_pol_hold(pol);
2207 }
2208
__xfrm_policy_unlink(struct xfrm_policy * pol,int dir)2209 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2210 int dir)
2211 {
2212 struct net *net = xp_net(pol);
2213
2214 if (list_empty(&pol->walk.all))
2215 return NULL;
2216
2217 /* Socket policies are not hashed. */
2218 if (!hlist_unhashed(&pol->bydst)) {
2219 hlist_del_rcu(&pol->bydst);
2220 hlist_del_init(&pol->bydst_inexact_list);
2221 hlist_del(&pol->byidx);
2222 }
2223
2224 list_del_init(&pol->walk.all);
2225 net->xfrm.policy_count[dir]--;
2226
2227 return pol;
2228 }
2229
xfrm_sk_policy_link(struct xfrm_policy * pol,int dir)2230 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2231 {
2232 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2233 }
2234
xfrm_sk_policy_unlink(struct xfrm_policy * pol,int dir)2235 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2236 {
2237 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2238 }
2239
xfrm_policy_delete(struct xfrm_policy * pol,int dir)2240 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2241 {
2242 struct net *net = xp_net(pol);
2243
2244 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2245 pol = __xfrm_policy_unlink(pol, dir);
2246 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2247 if (pol) {
2248 xfrm_policy_kill(pol);
2249 return 0;
2250 }
2251 return -ENOENT;
2252 }
2253 EXPORT_SYMBOL(xfrm_policy_delete);
2254
xfrm_sk_policy_insert(struct sock * sk,int dir,struct xfrm_policy * pol)2255 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2256 {
2257 struct net *net = sock_net(sk);
2258 struct xfrm_policy *old_pol;
2259
2260 #ifdef CONFIG_XFRM_SUB_POLICY
2261 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2262 return -EINVAL;
2263 #endif
2264
2265 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2266 old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2267 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2268 if (pol) {
2269 pol->curlft.add_time = ktime_get_real_seconds();
2270 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2271 xfrm_sk_policy_link(pol, dir);
2272 }
2273 rcu_assign_pointer(sk->sk_policy[dir], pol);
2274 if (old_pol) {
2275 if (pol)
2276 xfrm_policy_requeue(old_pol, pol);
2277
2278 /* Unlinking succeeds always. This is the only function
2279 * allowed to delete or replace socket policy.
2280 */
2281 xfrm_sk_policy_unlink(old_pol, dir);
2282 }
2283 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2284
2285 if (old_pol) {
2286 xfrm_policy_kill(old_pol);
2287 }
2288 return 0;
2289 }
2290
clone_policy(const struct xfrm_policy * old,int dir)2291 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2292 {
2293 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2294 struct net *net = xp_net(old);
2295
2296 if (newp) {
2297 newp->selector = old->selector;
2298 if (security_xfrm_policy_clone(old->security,
2299 &newp->security)) {
2300 kfree(newp);
2301 return NULL; /* ENOMEM */
2302 }
2303 newp->lft = old->lft;
2304 newp->curlft = old->curlft;
2305 newp->mark = old->mark;
2306 newp->if_id = old->if_id;
2307 newp->action = old->action;
2308 newp->flags = old->flags;
2309 newp->xfrm_nr = old->xfrm_nr;
2310 newp->index = old->index;
2311 newp->type = old->type;
2312 newp->family = old->family;
2313 memcpy(newp->xfrm_vec, old->xfrm_vec,
2314 newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2315 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2316 xfrm_sk_policy_link(newp, dir);
2317 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2318 xfrm_pol_put(newp);
2319 }
2320 return newp;
2321 }
2322
__xfrm_sk_clone_policy(struct sock * sk,const struct sock * osk)2323 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2324 {
2325 const struct xfrm_policy *p;
2326 struct xfrm_policy *np;
2327 int i, ret = 0;
2328
2329 rcu_read_lock();
2330 for (i = 0; i < 2; i++) {
2331 p = rcu_dereference(osk->sk_policy[i]);
2332 if (p) {
2333 np = clone_policy(p, i);
2334 if (unlikely(!np)) {
2335 ret = -ENOMEM;
2336 break;
2337 }
2338 rcu_assign_pointer(sk->sk_policy[i], np);
2339 }
2340 }
2341 rcu_read_unlock();
2342 return ret;
2343 }
2344
2345 static int
xfrm_get_saddr(struct net * net,int oif,xfrm_address_t * local,xfrm_address_t * remote,unsigned short family,u32 mark)2346 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2347 xfrm_address_t *remote, unsigned short family, u32 mark)
2348 {
2349 int err;
2350 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2351
2352 if (unlikely(afinfo == NULL))
2353 return -EINVAL;
2354 err = afinfo->get_saddr(net, oif, local, remote, mark);
2355 rcu_read_unlock();
2356 return err;
2357 }
2358
2359 /* Resolve list of templates for the flow, given policy. */
2360
2361 static int
xfrm_tmpl_resolve_one(struct xfrm_policy * policy,const struct flowi * fl,struct xfrm_state ** xfrm,unsigned short family)2362 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2363 struct xfrm_state **xfrm, unsigned short family)
2364 {
2365 struct net *net = xp_net(policy);
2366 int nx;
2367 int i, error;
2368 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2369 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2370 xfrm_address_t tmp;
2371
2372 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2373 struct xfrm_state *x;
2374 xfrm_address_t *remote = daddr;
2375 xfrm_address_t *local = saddr;
2376 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2377
2378 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2379 tmpl->mode == XFRM_MODE_BEET) {
2380 remote = &tmpl->id.daddr;
2381 local = &tmpl->saddr;
2382 if (xfrm_addr_any(local, tmpl->encap_family)) {
2383 error = xfrm_get_saddr(net, fl->flowi_oif,
2384 &tmp, remote,
2385 tmpl->encap_family, 0);
2386 if (error)
2387 goto fail;
2388 local = &tmp;
2389 }
2390 }
2391
2392 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2393 family, policy->if_id);
2394
2395 if (x && x->km.state == XFRM_STATE_VALID) {
2396 xfrm[nx++] = x;
2397 daddr = remote;
2398 saddr = local;
2399 continue;
2400 }
2401 if (x) {
2402 error = (x->km.state == XFRM_STATE_ERROR ?
2403 -EINVAL : -EAGAIN);
2404 xfrm_state_put(x);
2405 } else if (error == -ESRCH) {
2406 error = -EAGAIN;
2407 }
2408
2409 if (!tmpl->optional)
2410 goto fail;
2411 }
2412 return nx;
2413
2414 fail:
2415 for (nx--; nx >= 0; nx--)
2416 xfrm_state_put(xfrm[nx]);
2417 return error;
2418 }
2419
2420 static int
xfrm_tmpl_resolve(struct xfrm_policy ** pols,int npols,const struct flowi * fl,struct xfrm_state ** xfrm,unsigned short family)2421 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2422 struct xfrm_state **xfrm, unsigned short family)
2423 {
2424 struct xfrm_state *tp[XFRM_MAX_DEPTH];
2425 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2426 int cnx = 0;
2427 int error;
2428 int ret;
2429 int i;
2430
2431 for (i = 0; i < npols; i++) {
2432 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2433 error = -ENOBUFS;
2434 goto fail;
2435 }
2436
2437 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2438 if (ret < 0) {
2439 error = ret;
2440 goto fail;
2441 } else
2442 cnx += ret;
2443 }
2444
2445 /* found states are sorted for outbound processing */
2446 if (npols > 1)
2447 xfrm_state_sort(xfrm, tpp, cnx, family);
2448
2449 return cnx;
2450
2451 fail:
2452 for (cnx--; cnx >= 0; cnx--)
2453 xfrm_state_put(tpp[cnx]);
2454 return error;
2455
2456 }
2457
xfrm_get_tos(const struct flowi * fl,int family)2458 static int xfrm_get_tos(const struct flowi *fl, int family)
2459 {
2460 if (family == AF_INET)
2461 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2462
2463 return 0;
2464 }
2465
xfrm_alloc_dst(struct net * net,int family)2466 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2467 {
2468 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2469 struct dst_ops *dst_ops;
2470 struct xfrm_dst *xdst;
2471
2472 if (!afinfo)
2473 return ERR_PTR(-EINVAL);
2474
2475 switch (family) {
2476 case AF_INET:
2477 dst_ops = &net->xfrm.xfrm4_dst_ops;
2478 break;
2479 #if IS_ENABLED(CONFIG_IPV6)
2480 case AF_INET6:
2481 dst_ops = &net->xfrm.xfrm6_dst_ops;
2482 break;
2483 #endif
2484 default:
2485 BUG();
2486 }
2487 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2488
2489 if (likely(xdst)) {
2490 memset_after(xdst, 0, u.dst);
2491 } else
2492 xdst = ERR_PTR(-ENOBUFS);
2493
2494 rcu_read_unlock();
2495
2496 return xdst;
2497 }
2498
xfrm_init_path(struct xfrm_dst * path,struct dst_entry * dst,int nfheader_len)2499 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2500 int nfheader_len)
2501 {
2502 if (dst->ops->family == AF_INET6) {
2503 struct rt6_info *rt = (struct rt6_info *)dst;
2504 path->path_cookie = rt6_get_cookie(rt);
2505 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2506 }
2507 }
2508
xfrm_fill_dst(struct xfrm_dst * xdst,struct net_device * dev,const struct flowi * fl)2509 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2510 const struct flowi *fl)
2511 {
2512 const struct xfrm_policy_afinfo *afinfo =
2513 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2514 int err;
2515
2516 if (!afinfo)
2517 return -EINVAL;
2518
2519 err = afinfo->fill_dst(xdst, dev, fl);
2520
2521 rcu_read_unlock();
2522
2523 return err;
2524 }
2525
2526
2527 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2528 * all the metrics... Shortly, bundle a bundle.
2529 */
2530
xfrm_bundle_create(struct xfrm_policy * policy,struct xfrm_state ** xfrm,struct xfrm_dst ** bundle,int nx,const struct flowi * fl,struct dst_entry * dst)2531 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2532 struct xfrm_state **xfrm,
2533 struct xfrm_dst **bundle,
2534 int nx,
2535 const struct flowi *fl,
2536 struct dst_entry *dst)
2537 {
2538 const struct xfrm_state_afinfo *afinfo;
2539 const struct xfrm_mode *inner_mode;
2540 struct net *net = xp_net(policy);
2541 unsigned long now = jiffies;
2542 struct net_device *dev;
2543 struct xfrm_dst *xdst_prev = NULL;
2544 struct xfrm_dst *xdst0 = NULL;
2545 int i = 0;
2546 int err;
2547 int header_len = 0;
2548 int nfheader_len = 0;
2549 int trailer_len = 0;
2550 int tos;
2551 int family = policy->selector.family;
2552 xfrm_address_t saddr, daddr;
2553
2554 xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2555
2556 tos = xfrm_get_tos(fl, family);
2557
2558 dst_hold(dst);
2559
2560 for (; i < nx; i++) {
2561 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2562 struct dst_entry *dst1 = &xdst->u.dst;
2563
2564 err = PTR_ERR(xdst);
2565 if (IS_ERR(xdst)) {
2566 dst_release(dst);
2567 goto put_states;
2568 }
2569
2570 bundle[i] = xdst;
2571 if (!xdst_prev)
2572 xdst0 = xdst;
2573 else
2574 /* Ref count is taken during xfrm_alloc_dst()
2575 * No need to do dst_clone() on dst1
2576 */
2577 xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2578
2579 if (xfrm[i]->sel.family == AF_UNSPEC) {
2580 inner_mode = xfrm_ip2inner_mode(xfrm[i],
2581 xfrm_af2proto(family));
2582 if (!inner_mode) {
2583 err = -EAFNOSUPPORT;
2584 dst_release(dst);
2585 goto put_states;
2586 }
2587 } else
2588 inner_mode = &xfrm[i]->inner_mode;
2589
2590 xdst->route = dst;
2591 dst_copy_metrics(dst1, dst);
2592
2593 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2594 __u32 mark = 0;
2595 int oif;
2596
2597 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2598 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2599
2600 family = xfrm[i]->props.family;
2601 oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2602 dst = xfrm_dst_lookup(xfrm[i], tos, oif,
2603 &saddr, &daddr, family, mark);
2604 err = PTR_ERR(dst);
2605 if (IS_ERR(dst))
2606 goto put_states;
2607 } else
2608 dst_hold(dst);
2609
2610 dst1->xfrm = xfrm[i];
2611 xdst->xfrm_genid = xfrm[i]->genid;
2612
2613 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2614 dst1->lastuse = now;
2615
2616 dst1->input = dst_discard;
2617
2618 rcu_read_lock();
2619 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2620 if (likely(afinfo))
2621 dst1->output = afinfo->output;
2622 else
2623 dst1->output = dst_discard_out;
2624 rcu_read_unlock();
2625
2626 xdst_prev = xdst;
2627
2628 header_len += xfrm[i]->props.header_len;
2629 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2630 nfheader_len += xfrm[i]->props.header_len;
2631 trailer_len += xfrm[i]->props.trailer_len;
2632 }
2633
2634 xfrm_dst_set_child(xdst_prev, dst);
2635 xdst0->path = dst;
2636
2637 err = -ENODEV;
2638 dev = dst->dev;
2639 if (!dev)
2640 goto free_dst;
2641
2642 xfrm_init_path(xdst0, dst, nfheader_len);
2643 xfrm_init_pmtu(bundle, nx);
2644
2645 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2646 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2647 err = xfrm_fill_dst(xdst_prev, dev, fl);
2648 if (err)
2649 goto free_dst;
2650
2651 xdst_prev->u.dst.header_len = header_len;
2652 xdst_prev->u.dst.trailer_len = trailer_len;
2653 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2654 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2655 }
2656
2657 return &xdst0->u.dst;
2658
2659 put_states:
2660 for (; i < nx; i++)
2661 xfrm_state_put(xfrm[i]);
2662 free_dst:
2663 if (xdst0)
2664 dst_release_immediate(&xdst0->u.dst);
2665
2666 return ERR_PTR(err);
2667 }
2668
xfrm_expand_policies(const struct flowi * fl,u16 family,struct xfrm_policy ** pols,int * num_pols,int * num_xfrms)2669 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2670 struct xfrm_policy **pols,
2671 int *num_pols, int *num_xfrms)
2672 {
2673 int i;
2674
2675 if (*num_pols == 0 || !pols[0]) {
2676 *num_pols = 0;
2677 *num_xfrms = 0;
2678 return 0;
2679 }
2680 if (IS_ERR(pols[0])) {
2681 *num_pols = 0;
2682 return PTR_ERR(pols[0]);
2683 }
2684
2685 *num_xfrms = pols[0]->xfrm_nr;
2686
2687 #ifdef CONFIG_XFRM_SUB_POLICY
2688 if (pols[0]->action == XFRM_POLICY_ALLOW &&
2689 pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2690 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2691 XFRM_POLICY_TYPE_MAIN,
2692 fl, family,
2693 XFRM_POLICY_OUT,
2694 pols[0]->if_id);
2695 if (pols[1]) {
2696 if (IS_ERR(pols[1])) {
2697 xfrm_pols_put(pols, *num_pols);
2698 *num_pols = 0;
2699 return PTR_ERR(pols[1]);
2700 }
2701 (*num_pols)++;
2702 (*num_xfrms) += pols[1]->xfrm_nr;
2703 }
2704 }
2705 #endif
2706 for (i = 0; i < *num_pols; i++) {
2707 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2708 *num_xfrms = -1;
2709 break;
2710 }
2711 }
2712
2713 return 0;
2714
2715 }
2716
2717 static struct xfrm_dst *
xfrm_resolve_and_create_bundle(struct xfrm_policy ** pols,int num_pols,const struct flowi * fl,u16 family,struct dst_entry * dst_orig)2718 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2719 const struct flowi *fl, u16 family,
2720 struct dst_entry *dst_orig)
2721 {
2722 struct net *net = xp_net(pols[0]);
2723 struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2724 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2725 struct xfrm_dst *xdst;
2726 struct dst_entry *dst;
2727 int err;
2728
2729 /* Try to instantiate a bundle */
2730 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2731 if (err <= 0) {
2732 if (err == 0)
2733 return NULL;
2734
2735 if (err != -EAGAIN)
2736 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2737 return ERR_PTR(err);
2738 }
2739
2740 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2741 if (IS_ERR(dst)) {
2742 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2743 return ERR_CAST(dst);
2744 }
2745
2746 xdst = (struct xfrm_dst *)dst;
2747 xdst->num_xfrms = err;
2748 xdst->num_pols = num_pols;
2749 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2750 xdst->policy_genid = atomic_read(&pols[0]->genid);
2751
2752 return xdst;
2753 }
2754
xfrm_policy_queue_process(struct timer_list * t)2755 static void xfrm_policy_queue_process(struct timer_list *t)
2756 {
2757 struct sk_buff *skb;
2758 struct sock *sk;
2759 struct dst_entry *dst;
2760 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2761 struct net *net = xp_net(pol);
2762 struct xfrm_policy_queue *pq = &pol->polq;
2763 struct flowi fl;
2764 struct sk_buff_head list;
2765 __u32 skb_mark;
2766
2767 spin_lock(&pq->hold_queue.lock);
2768 skb = skb_peek(&pq->hold_queue);
2769 if (!skb) {
2770 spin_unlock(&pq->hold_queue.lock);
2771 goto out;
2772 }
2773 dst = skb_dst(skb);
2774 sk = skb->sk;
2775
2776 /* Fixup the mark to support VTI. */
2777 skb_mark = skb->mark;
2778 skb->mark = pol->mark.v;
2779 xfrm_decode_session(skb, &fl, dst->ops->family);
2780 skb->mark = skb_mark;
2781 spin_unlock(&pq->hold_queue.lock);
2782
2783 dst_hold(xfrm_dst_path(dst));
2784 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2785 if (IS_ERR(dst))
2786 goto purge_queue;
2787
2788 if (dst->flags & DST_XFRM_QUEUE) {
2789 dst_release(dst);
2790
2791 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2792 goto purge_queue;
2793
2794 pq->timeout = pq->timeout << 1;
2795 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2796 xfrm_pol_hold(pol);
2797 goto out;
2798 }
2799
2800 dst_release(dst);
2801
2802 __skb_queue_head_init(&list);
2803
2804 spin_lock(&pq->hold_queue.lock);
2805 pq->timeout = 0;
2806 skb_queue_splice_init(&pq->hold_queue, &list);
2807 spin_unlock(&pq->hold_queue.lock);
2808
2809 while (!skb_queue_empty(&list)) {
2810 skb = __skb_dequeue(&list);
2811
2812 /* Fixup the mark to support VTI. */
2813 skb_mark = skb->mark;
2814 skb->mark = pol->mark.v;
2815 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2816 skb->mark = skb_mark;
2817
2818 dst_hold(xfrm_dst_path(skb_dst(skb)));
2819 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2820 if (IS_ERR(dst)) {
2821 kfree_skb(skb);
2822 continue;
2823 }
2824
2825 nf_reset_ct(skb);
2826 skb_dst_drop(skb);
2827 skb_dst_set(skb, dst);
2828
2829 dst_output(net, skb->sk, skb);
2830 }
2831
2832 out:
2833 xfrm_pol_put(pol);
2834 return;
2835
2836 purge_queue:
2837 pq->timeout = 0;
2838 skb_queue_purge(&pq->hold_queue);
2839 xfrm_pol_put(pol);
2840 }
2841
xdst_queue_output(struct net * net,struct sock * sk,struct sk_buff * skb)2842 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2843 {
2844 unsigned long sched_next;
2845 struct dst_entry *dst = skb_dst(skb);
2846 struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2847 struct xfrm_policy *pol = xdst->pols[0];
2848 struct xfrm_policy_queue *pq = &pol->polq;
2849
2850 if (unlikely(skb_fclone_busy(sk, skb))) {
2851 kfree_skb(skb);
2852 return 0;
2853 }
2854
2855 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2856 kfree_skb(skb);
2857 return -EAGAIN;
2858 }
2859
2860 skb_dst_force(skb);
2861
2862 spin_lock_bh(&pq->hold_queue.lock);
2863
2864 if (!pq->timeout)
2865 pq->timeout = XFRM_QUEUE_TMO_MIN;
2866
2867 sched_next = jiffies + pq->timeout;
2868
2869 if (del_timer(&pq->hold_timer)) {
2870 if (time_before(pq->hold_timer.expires, sched_next))
2871 sched_next = pq->hold_timer.expires;
2872 xfrm_pol_put(pol);
2873 }
2874
2875 __skb_queue_tail(&pq->hold_queue, skb);
2876 if (!mod_timer(&pq->hold_timer, sched_next))
2877 xfrm_pol_hold(pol);
2878
2879 spin_unlock_bh(&pq->hold_queue.lock);
2880
2881 return 0;
2882 }
2883
xfrm_create_dummy_bundle(struct net * net,struct xfrm_flo * xflo,const struct flowi * fl,int num_xfrms,u16 family)2884 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2885 struct xfrm_flo *xflo,
2886 const struct flowi *fl,
2887 int num_xfrms,
2888 u16 family)
2889 {
2890 int err;
2891 struct net_device *dev;
2892 struct dst_entry *dst;
2893 struct dst_entry *dst1;
2894 struct xfrm_dst *xdst;
2895
2896 xdst = xfrm_alloc_dst(net, family);
2897 if (IS_ERR(xdst))
2898 return xdst;
2899
2900 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2901 net->xfrm.sysctl_larval_drop ||
2902 num_xfrms <= 0)
2903 return xdst;
2904
2905 dst = xflo->dst_orig;
2906 dst1 = &xdst->u.dst;
2907 dst_hold(dst);
2908 xdst->route = dst;
2909
2910 dst_copy_metrics(dst1, dst);
2911
2912 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2913 dst1->flags |= DST_XFRM_QUEUE;
2914 dst1->lastuse = jiffies;
2915
2916 dst1->input = dst_discard;
2917 dst1->output = xdst_queue_output;
2918
2919 dst_hold(dst);
2920 xfrm_dst_set_child(xdst, dst);
2921 xdst->path = dst;
2922
2923 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2924
2925 err = -ENODEV;
2926 dev = dst->dev;
2927 if (!dev)
2928 goto free_dst;
2929
2930 err = xfrm_fill_dst(xdst, dev, fl);
2931 if (err)
2932 goto free_dst;
2933
2934 out:
2935 return xdst;
2936
2937 free_dst:
2938 dst_release(dst1);
2939 xdst = ERR_PTR(err);
2940 goto out;
2941 }
2942
xfrm_bundle_lookup(struct net * net,const struct flowi * fl,u16 family,u8 dir,struct xfrm_flo * xflo,u32 if_id)2943 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
2944 const struct flowi *fl,
2945 u16 family, u8 dir,
2946 struct xfrm_flo *xflo, u32 if_id)
2947 {
2948 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2949 int num_pols = 0, num_xfrms = 0, err;
2950 struct xfrm_dst *xdst;
2951
2952 /* Resolve policies to use if we couldn't get them from
2953 * previous cache entry */
2954 num_pols = 1;
2955 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
2956 err = xfrm_expand_policies(fl, family, pols,
2957 &num_pols, &num_xfrms);
2958 if (err < 0)
2959 goto inc_error;
2960 if (num_pols == 0)
2961 return NULL;
2962 if (num_xfrms <= 0)
2963 goto make_dummy_bundle;
2964
2965 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2966 xflo->dst_orig);
2967 if (IS_ERR(xdst)) {
2968 err = PTR_ERR(xdst);
2969 if (err == -EREMOTE) {
2970 xfrm_pols_put(pols, num_pols);
2971 return NULL;
2972 }
2973
2974 if (err != -EAGAIN)
2975 goto error;
2976 goto make_dummy_bundle;
2977 } else if (xdst == NULL) {
2978 num_xfrms = 0;
2979 goto make_dummy_bundle;
2980 }
2981
2982 return xdst;
2983
2984 make_dummy_bundle:
2985 /* We found policies, but there's no bundles to instantiate:
2986 * either because the policy blocks, has no transformations or
2987 * we could not build template (no xfrm_states).*/
2988 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2989 if (IS_ERR(xdst)) {
2990 xfrm_pols_put(pols, num_pols);
2991 return ERR_CAST(xdst);
2992 }
2993 xdst->num_pols = num_pols;
2994 xdst->num_xfrms = num_xfrms;
2995 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2996
2997 return xdst;
2998
2999 inc_error:
3000 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3001 error:
3002 xfrm_pols_put(pols, num_pols);
3003 return ERR_PTR(err);
3004 }
3005
make_blackhole(struct net * net,u16 family,struct dst_entry * dst_orig)3006 static struct dst_entry *make_blackhole(struct net *net, u16 family,
3007 struct dst_entry *dst_orig)
3008 {
3009 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3010 struct dst_entry *ret;
3011
3012 if (!afinfo) {
3013 dst_release(dst_orig);
3014 return ERR_PTR(-EINVAL);
3015 } else {
3016 ret = afinfo->blackhole_route(net, dst_orig);
3017 }
3018 rcu_read_unlock();
3019
3020 return ret;
3021 }
3022
3023 /* Finds/creates a bundle for given flow and if_id
3024 *
3025 * At the moment we eat a raw IP route. Mostly to speed up lookups
3026 * on interfaces with disabled IPsec.
3027 *
3028 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3029 * compatibility
3030 */
xfrm_lookup_with_ifid(struct net * net,struct dst_entry * dst_orig,const struct flowi * fl,const struct sock * sk,int flags,u32 if_id)3031 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3032 struct dst_entry *dst_orig,
3033 const struct flowi *fl,
3034 const struct sock *sk,
3035 int flags, u32 if_id)
3036 {
3037 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3038 struct xfrm_dst *xdst;
3039 struct dst_entry *dst, *route;
3040 u16 family = dst_orig->ops->family;
3041 u8 dir = XFRM_POLICY_OUT;
3042 int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3043
3044 dst = NULL;
3045 xdst = NULL;
3046 route = NULL;
3047
3048 sk = sk_const_to_full_sk(sk);
3049 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3050 num_pols = 1;
3051 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3052 if_id);
3053 err = xfrm_expand_policies(fl, family, pols,
3054 &num_pols, &num_xfrms);
3055 if (err < 0)
3056 goto dropdst;
3057
3058 if (num_pols) {
3059 if (num_xfrms <= 0) {
3060 drop_pols = num_pols;
3061 goto no_transform;
3062 }
3063
3064 xdst = xfrm_resolve_and_create_bundle(
3065 pols, num_pols, fl,
3066 family, dst_orig);
3067
3068 if (IS_ERR(xdst)) {
3069 xfrm_pols_put(pols, num_pols);
3070 err = PTR_ERR(xdst);
3071 if (err == -EREMOTE)
3072 goto nopol;
3073
3074 goto dropdst;
3075 } else if (xdst == NULL) {
3076 num_xfrms = 0;
3077 drop_pols = num_pols;
3078 goto no_transform;
3079 }
3080
3081 route = xdst->route;
3082 }
3083 }
3084
3085 if (xdst == NULL) {
3086 struct xfrm_flo xflo;
3087
3088 xflo.dst_orig = dst_orig;
3089 xflo.flags = flags;
3090
3091 /* To accelerate a bit... */
3092 if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3093 !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3094 goto nopol;
3095
3096 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3097 if (xdst == NULL)
3098 goto nopol;
3099 if (IS_ERR(xdst)) {
3100 err = PTR_ERR(xdst);
3101 goto dropdst;
3102 }
3103
3104 num_pols = xdst->num_pols;
3105 num_xfrms = xdst->num_xfrms;
3106 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3107 route = xdst->route;
3108 }
3109
3110 dst = &xdst->u.dst;
3111 if (route == NULL && num_xfrms > 0) {
3112 /* The only case when xfrm_bundle_lookup() returns a
3113 * bundle with null route, is when the template could
3114 * not be resolved. It means policies are there, but
3115 * bundle could not be created, since we don't yet
3116 * have the xfrm_state's. We need to wait for KM to
3117 * negotiate new SA's or bail out with error.*/
3118 if (net->xfrm.sysctl_larval_drop) {
3119 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3120 err = -EREMOTE;
3121 goto error;
3122 }
3123
3124 err = -EAGAIN;
3125
3126 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3127 goto error;
3128 }
3129
3130 no_transform:
3131 if (num_pols == 0)
3132 goto nopol;
3133
3134 if ((flags & XFRM_LOOKUP_ICMP) &&
3135 !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3136 err = -ENOENT;
3137 goto error;
3138 }
3139
3140 for (i = 0; i < num_pols; i++)
3141 pols[i]->curlft.use_time = ktime_get_real_seconds();
3142
3143 if (num_xfrms < 0) {
3144 /* Prohibit the flow */
3145 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3146 err = -EPERM;
3147 goto error;
3148 } else if (num_xfrms > 0) {
3149 /* Flow transformed */
3150 dst_release(dst_orig);
3151 } else {
3152 /* Flow passes untransformed */
3153 dst_release(dst);
3154 dst = dst_orig;
3155 }
3156 ok:
3157 xfrm_pols_put(pols, drop_pols);
3158 if (dst && dst->xfrm &&
3159 dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3160 dst->flags |= DST_XFRM_TUNNEL;
3161 return dst;
3162
3163 nopol:
3164 if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3165 net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3166 err = -EPERM;
3167 goto error;
3168 }
3169 if (!(flags & XFRM_LOOKUP_ICMP)) {
3170 dst = dst_orig;
3171 goto ok;
3172 }
3173 err = -ENOENT;
3174 error:
3175 dst_release(dst);
3176 dropdst:
3177 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3178 dst_release(dst_orig);
3179 xfrm_pols_put(pols, drop_pols);
3180 return ERR_PTR(err);
3181 }
3182 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3183
3184 /* Main function: finds/creates a bundle for given flow.
3185 *
3186 * At the moment we eat a raw IP route. Mostly to speed up lookups
3187 * on interfaces with disabled IPsec.
3188 */
xfrm_lookup(struct net * net,struct dst_entry * dst_orig,const struct flowi * fl,const struct sock * sk,int flags)3189 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3190 const struct flowi *fl, const struct sock *sk,
3191 int flags)
3192 {
3193 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3194 }
3195 EXPORT_SYMBOL(xfrm_lookup);
3196
3197 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3198 * Otherwise we may send out blackholed packets.
3199 */
xfrm_lookup_route(struct net * net,struct dst_entry * dst_orig,const struct flowi * fl,const struct sock * sk,int flags)3200 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3201 const struct flowi *fl,
3202 const struct sock *sk, int flags)
3203 {
3204 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3205 flags | XFRM_LOOKUP_QUEUE |
3206 XFRM_LOOKUP_KEEP_DST_REF);
3207
3208 if (PTR_ERR(dst) == -EREMOTE)
3209 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3210
3211 if (IS_ERR(dst))
3212 dst_release(dst_orig);
3213
3214 return dst;
3215 }
3216 EXPORT_SYMBOL(xfrm_lookup_route);
3217
3218 static inline int
xfrm_secpath_reject(int idx,struct sk_buff * skb,const struct flowi * fl)3219 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3220 {
3221 struct sec_path *sp = skb_sec_path(skb);
3222 struct xfrm_state *x;
3223
3224 if (!sp || idx < 0 || idx >= sp->len)
3225 return 0;
3226 x = sp->xvec[idx];
3227 if (!x->type->reject)
3228 return 0;
3229 return x->type->reject(x, skb, fl);
3230 }
3231
3232 /* When skb is transformed back to its "native" form, we have to
3233 * check policy restrictions. At the moment we make this in maximally
3234 * stupid way. Shame on me. :-) Of course, connected sockets must
3235 * have policy cached at them.
3236 */
3237
3238 static inline int
xfrm_state_ok(const struct xfrm_tmpl * tmpl,const struct xfrm_state * x,unsigned short family)3239 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3240 unsigned short family)
3241 {
3242 if (xfrm_state_kern(x))
3243 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3244 return x->id.proto == tmpl->id.proto &&
3245 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3246 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3247 x->props.mode == tmpl->mode &&
3248 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3249 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3250 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3251 xfrm_state_addr_cmp(tmpl, x, family));
3252 }
3253
3254 /*
3255 * 0 or more than 0 is returned when validation is succeeded (either bypass
3256 * because of optional transport mode, or next index of the matched secpath
3257 * state with the template.
3258 * -1 is returned when no matching template is found.
3259 * Otherwise "-2 - errored_index" is returned.
3260 */
3261 static inline int
xfrm_policy_ok(const struct xfrm_tmpl * tmpl,const struct sec_path * sp,int start,unsigned short family)3262 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3263 unsigned short family)
3264 {
3265 int idx = start;
3266
3267 if (tmpl->optional) {
3268 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3269 return start;
3270 } else
3271 start = -1;
3272 for (; idx < sp->len; idx++) {
3273 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
3274 return ++idx;
3275 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3276 if (start == -1)
3277 start = -2-idx;
3278 break;
3279 }
3280 }
3281 return start;
3282 }
3283
3284 static void
decode_session4(struct sk_buff * skb,struct flowi * fl,bool reverse)3285 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3286 {
3287 const struct iphdr *iph = ip_hdr(skb);
3288 int ihl = iph->ihl;
3289 u8 *xprth = skb_network_header(skb) + ihl * 4;
3290 struct flowi4 *fl4 = &fl->u.ip4;
3291 int oif = 0;
3292
3293 if (skb_dst(skb) && skb_dst(skb)->dev)
3294 oif = skb_dst(skb)->dev->ifindex;
3295
3296 memset(fl4, 0, sizeof(struct flowi4));
3297 fl4->flowi4_mark = skb->mark;
3298 fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3299
3300 fl4->flowi4_proto = iph->protocol;
3301 fl4->daddr = reverse ? iph->saddr : iph->daddr;
3302 fl4->saddr = reverse ? iph->daddr : iph->saddr;
3303 fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK;
3304
3305 if (!ip_is_fragment(iph)) {
3306 switch (iph->protocol) {
3307 case IPPROTO_UDP:
3308 case IPPROTO_UDPLITE:
3309 case IPPROTO_TCP:
3310 case IPPROTO_SCTP:
3311 case IPPROTO_DCCP:
3312 if (xprth + 4 < skb->data ||
3313 pskb_may_pull(skb, xprth + 4 - skb->data)) {
3314 __be16 *ports;
3315
3316 xprth = skb_network_header(skb) + ihl * 4;
3317 ports = (__be16 *)xprth;
3318
3319 fl4->fl4_sport = ports[!!reverse];
3320 fl4->fl4_dport = ports[!reverse];
3321 }
3322 break;
3323 case IPPROTO_ICMP:
3324 if (xprth + 2 < skb->data ||
3325 pskb_may_pull(skb, xprth + 2 - skb->data)) {
3326 u8 *icmp;
3327
3328 xprth = skb_network_header(skb) + ihl * 4;
3329 icmp = xprth;
3330
3331 fl4->fl4_icmp_type = icmp[0];
3332 fl4->fl4_icmp_code = icmp[1];
3333 }
3334 break;
3335 case IPPROTO_GRE:
3336 if (xprth + 12 < skb->data ||
3337 pskb_may_pull(skb, xprth + 12 - skb->data)) {
3338 __be16 *greflags;
3339 __be32 *gre_hdr;
3340
3341 xprth = skb_network_header(skb) + ihl * 4;
3342 greflags = (__be16 *)xprth;
3343 gre_hdr = (__be32 *)xprth;
3344
3345 if (greflags[0] & GRE_KEY) {
3346 if (greflags[0] & GRE_CSUM)
3347 gre_hdr++;
3348 fl4->fl4_gre_key = gre_hdr[1];
3349 }
3350 }
3351 break;
3352 default:
3353 break;
3354 }
3355 }
3356 }
3357
3358 #if IS_ENABLED(CONFIG_IPV6)
3359 static void
decode_session6(struct sk_buff * skb,struct flowi * fl,bool reverse)3360 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3361 {
3362 struct flowi6 *fl6 = &fl->u.ip6;
3363 int onlyproto = 0;
3364 const struct ipv6hdr *hdr = ipv6_hdr(skb);
3365 u32 offset = sizeof(*hdr);
3366 struct ipv6_opt_hdr *exthdr;
3367 const unsigned char *nh = skb_network_header(skb);
3368 u16 nhoff = IP6CB(skb)->nhoff;
3369 int oif = 0;
3370 u8 nexthdr;
3371
3372 if (!nhoff)
3373 nhoff = offsetof(struct ipv6hdr, nexthdr);
3374
3375 nexthdr = nh[nhoff];
3376
3377 if (skb_dst(skb) && skb_dst(skb)->dev)
3378 oif = skb_dst(skb)->dev->ifindex;
3379
3380 memset(fl6, 0, sizeof(struct flowi6));
3381 fl6->flowi6_mark = skb->mark;
3382 fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3383
3384 fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3385 fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3386
3387 while (nh + offset + sizeof(*exthdr) < skb->data ||
3388 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3389 nh = skb_network_header(skb);
3390 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3391
3392 switch (nexthdr) {
3393 case NEXTHDR_FRAGMENT:
3394 onlyproto = 1;
3395 fallthrough;
3396 case NEXTHDR_ROUTING:
3397 case NEXTHDR_HOP:
3398 case NEXTHDR_DEST:
3399 offset += ipv6_optlen(exthdr);
3400 nexthdr = exthdr->nexthdr;
3401 break;
3402 case IPPROTO_UDP:
3403 case IPPROTO_UDPLITE:
3404 case IPPROTO_TCP:
3405 case IPPROTO_SCTP:
3406 case IPPROTO_DCCP:
3407 if (!onlyproto && (nh + offset + 4 < skb->data ||
3408 pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3409 __be16 *ports;
3410
3411 nh = skb_network_header(skb);
3412 ports = (__be16 *)(nh + offset);
3413 fl6->fl6_sport = ports[!!reverse];
3414 fl6->fl6_dport = ports[!reverse];
3415 }
3416 fl6->flowi6_proto = nexthdr;
3417 return;
3418 case IPPROTO_ICMPV6:
3419 if (!onlyproto && (nh + offset + 2 < skb->data ||
3420 pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3421 u8 *icmp;
3422
3423 nh = skb_network_header(skb);
3424 icmp = (u8 *)(nh + offset);
3425 fl6->fl6_icmp_type = icmp[0];
3426 fl6->fl6_icmp_code = icmp[1];
3427 }
3428 fl6->flowi6_proto = nexthdr;
3429 return;
3430 case IPPROTO_GRE:
3431 if (!onlyproto &&
3432 (nh + offset + 12 < skb->data ||
3433 pskb_may_pull(skb, nh + offset + 12 - skb->data))) {
3434 struct gre_base_hdr *gre_hdr;
3435 __be32 *gre_key;
3436
3437 nh = skb_network_header(skb);
3438 gre_hdr = (struct gre_base_hdr *)(nh + offset);
3439 gre_key = (__be32 *)(gre_hdr + 1);
3440
3441 if (gre_hdr->flags & GRE_KEY) {
3442 if (gre_hdr->flags & GRE_CSUM)
3443 gre_key++;
3444 fl6->fl6_gre_key = *gre_key;
3445 }
3446 }
3447 fl6->flowi6_proto = nexthdr;
3448 return;
3449
3450 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3451 case IPPROTO_MH:
3452 offset += ipv6_optlen(exthdr);
3453 if (!onlyproto && (nh + offset + 3 < skb->data ||
3454 pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3455 struct ip6_mh *mh;
3456
3457 nh = skb_network_header(skb);
3458 mh = (struct ip6_mh *)(nh + offset);
3459 fl6->fl6_mh_type = mh->ip6mh_type;
3460 }
3461 fl6->flowi6_proto = nexthdr;
3462 return;
3463 #endif
3464 default:
3465 fl6->flowi6_proto = nexthdr;
3466 return;
3467 }
3468 }
3469 }
3470 #endif
3471
__xfrm_decode_session(struct sk_buff * skb,struct flowi * fl,unsigned int family,int reverse)3472 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3473 unsigned int family, int reverse)
3474 {
3475 switch (family) {
3476 case AF_INET:
3477 decode_session4(skb, fl, reverse);
3478 break;
3479 #if IS_ENABLED(CONFIG_IPV6)
3480 case AF_INET6:
3481 decode_session6(skb, fl, reverse);
3482 break;
3483 #endif
3484 default:
3485 return -EAFNOSUPPORT;
3486 }
3487
3488 return security_xfrm_decode_session(skb, &fl->flowi_secid);
3489 }
3490 EXPORT_SYMBOL(__xfrm_decode_session);
3491
secpath_has_nontransport(const struct sec_path * sp,int k,int * idxp)3492 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3493 {
3494 for (; k < sp->len; k++) {
3495 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3496 *idxp = k;
3497 return 1;
3498 }
3499 }
3500
3501 return 0;
3502 }
3503
__xfrm_policy_check(struct sock * sk,int dir,struct sk_buff * skb,unsigned short family)3504 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3505 unsigned short family)
3506 {
3507 struct net *net = dev_net(skb->dev);
3508 struct xfrm_policy *pol;
3509 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3510 int npols = 0;
3511 int xfrm_nr;
3512 int pi;
3513 int reverse;
3514 struct flowi fl;
3515 int xerr_idx = -1;
3516 const struct xfrm_if_cb *ifcb;
3517 struct sec_path *sp;
3518 u32 if_id = 0;
3519
3520 rcu_read_lock();
3521 ifcb = xfrm_if_get_cb();
3522
3523 if (ifcb) {
3524 struct xfrm_if_decode_session_result r;
3525
3526 if (ifcb->decode_session(skb, family, &r)) {
3527 if_id = r.if_id;
3528 net = r.net;
3529 }
3530 }
3531 rcu_read_unlock();
3532
3533 reverse = dir & ~XFRM_POLICY_MASK;
3534 dir &= XFRM_POLICY_MASK;
3535
3536 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3537 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3538 return 0;
3539 }
3540
3541 nf_nat_decode_session(skb, &fl, family);
3542
3543 /* First, check used SA against their selectors. */
3544 sp = skb_sec_path(skb);
3545 if (sp) {
3546 int i;
3547
3548 for (i = sp->len - 1; i >= 0; i--) {
3549 struct xfrm_state *x = sp->xvec[i];
3550 if (!xfrm_selector_match(&x->sel, &fl, family)) {
3551 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3552 return 0;
3553 }
3554 }
3555 }
3556
3557 pol = NULL;
3558 sk = sk_to_full_sk(sk);
3559 if (sk && sk->sk_policy[dir]) {
3560 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3561 if (IS_ERR(pol)) {
3562 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3563 return 0;
3564 }
3565 }
3566
3567 if (!pol)
3568 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3569
3570 if (IS_ERR(pol)) {
3571 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3572 return 0;
3573 }
3574
3575 if (!pol) {
3576 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3577 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3578 return 0;
3579 }
3580
3581 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3582 xfrm_secpath_reject(xerr_idx, skb, &fl);
3583 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3584 return 0;
3585 }
3586 return 1;
3587 }
3588
3589 pol->curlft.use_time = ktime_get_real_seconds();
3590
3591 pols[0] = pol;
3592 npols++;
3593 #ifdef CONFIG_XFRM_SUB_POLICY
3594 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3595 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3596 &fl, family,
3597 XFRM_POLICY_IN, if_id);
3598 if (pols[1]) {
3599 if (IS_ERR(pols[1])) {
3600 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3601 xfrm_pol_put(pols[0]);
3602 return 0;
3603 }
3604 pols[1]->curlft.use_time = ktime_get_real_seconds();
3605 npols++;
3606 }
3607 }
3608 #endif
3609
3610 if (pol->action == XFRM_POLICY_ALLOW) {
3611 static struct sec_path dummy;
3612 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3613 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3614 struct xfrm_tmpl **tpp = tp;
3615 int ti = 0;
3616 int i, k;
3617
3618 sp = skb_sec_path(skb);
3619 if (!sp)
3620 sp = &dummy;
3621
3622 for (pi = 0; pi < npols; pi++) {
3623 if (pols[pi] != pol &&
3624 pols[pi]->action != XFRM_POLICY_ALLOW) {
3625 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3626 goto reject;
3627 }
3628 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3629 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3630 goto reject_error;
3631 }
3632 for (i = 0; i < pols[pi]->xfrm_nr; i++)
3633 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3634 }
3635 xfrm_nr = ti;
3636
3637 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK &&
3638 !xfrm_nr) {
3639 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
3640 goto reject;
3641 }
3642
3643 if (npols > 1) {
3644 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3645 tpp = stp;
3646 }
3647
3648 /* For each tunnel xfrm, find the first matching tmpl.
3649 * For each tmpl before that, find corresponding xfrm.
3650 * Order is _important_. Later we will implement
3651 * some barriers, but at the moment barriers
3652 * are implied between each two transformations.
3653 */
3654 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3655 k = xfrm_policy_ok(tpp[i], sp, k, family);
3656 if (k < 0) {
3657 if (k < -1)
3658 /* "-2 - errored_index" returned */
3659 xerr_idx = -(2+k);
3660 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3661 goto reject;
3662 }
3663 }
3664
3665 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3666 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3667 goto reject;
3668 }
3669
3670 xfrm_pols_put(pols, npols);
3671 return 1;
3672 }
3673 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3674
3675 reject:
3676 xfrm_secpath_reject(xerr_idx, skb, &fl);
3677 reject_error:
3678 xfrm_pols_put(pols, npols);
3679 return 0;
3680 }
3681 EXPORT_SYMBOL(__xfrm_policy_check);
3682
__xfrm_route_forward(struct sk_buff * skb,unsigned short family)3683 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3684 {
3685 struct net *net = dev_net(skb->dev);
3686 struct flowi fl;
3687 struct dst_entry *dst;
3688 int res = 1;
3689
3690 if (xfrm_decode_session(skb, &fl, family) < 0) {
3691 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3692 return 0;
3693 }
3694
3695 skb_dst_force(skb);
3696 if (!skb_dst(skb)) {
3697 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3698 return 0;
3699 }
3700
3701 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3702 if (IS_ERR(dst)) {
3703 res = 0;
3704 dst = NULL;
3705 }
3706 skb_dst_set(skb, dst);
3707 return res;
3708 }
3709 EXPORT_SYMBOL(__xfrm_route_forward);
3710
3711 /* Optimize later using cookies and generation ids. */
3712
xfrm_dst_check(struct dst_entry * dst,u32 cookie)3713 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3714 {
3715 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3716 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3717 * get validated by dst_ops->check on every use. We do this
3718 * because when a normal route referenced by an XFRM dst is
3719 * obsoleted we do not go looking around for all parent
3720 * referencing XFRM dsts so that we can invalidate them. It
3721 * is just too much work. Instead we make the checks here on
3722 * every use. For example:
3723 *
3724 * XFRM dst A --> IPv4 dst X
3725 *
3726 * X is the "xdst->route" of A (X is also the "dst->path" of A
3727 * in this example). If X is marked obsolete, "A" will not
3728 * notice. That's what we are validating here via the
3729 * stale_bundle() check.
3730 *
3731 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3732 * be marked on it.
3733 * This will force stale_bundle() to fail on any xdst bundle with
3734 * this dst linked in it.
3735 */
3736 if (dst->obsolete < 0 && !stale_bundle(dst))
3737 return dst;
3738
3739 return NULL;
3740 }
3741
stale_bundle(struct dst_entry * dst)3742 static int stale_bundle(struct dst_entry *dst)
3743 {
3744 return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3745 }
3746
xfrm_dst_ifdown(struct dst_entry * dst,struct net_device * dev)3747 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3748 {
3749 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3750 dst->dev = blackhole_netdev;
3751 dev_hold(dst->dev);
3752 dev_put(dev);
3753 }
3754 }
3755 EXPORT_SYMBOL(xfrm_dst_ifdown);
3756
xfrm_link_failure(struct sk_buff * skb)3757 static void xfrm_link_failure(struct sk_buff *skb)
3758 {
3759 /* Impossible. Such dst must be popped before reaches point of failure. */
3760 }
3761
xfrm_negative_advice(struct dst_entry * dst)3762 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3763 {
3764 if (dst) {
3765 if (dst->obsolete) {
3766 dst_release(dst);
3767 dst = NULL;
3768 }
3769 }
3770 return dst;
3771 }
3772
xfrm_init_pmtu(struct xfrm_dst ** bundle,int nr)3773 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3774 {
3775 while (nr--) {
3776 struct xfrm_dst *xdst = bundle[nr];
3777 u32 pmtu, route_mtu_cached;
3778 struct dst_entry *dst;
3779
3780 dst = &xdst->u.dst;
3781 pmtu = dst_mtu(xfrm_dst_child(dst));
3782 xdst->child_mtu_cached = pmtu;
3783
3784 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3785
3786 route_mtu_cached = dst_mtu(xdst->route);
3787 xdst->route_mtu_cached = route_mtu_cached;
3788
3789 if (pmtu > route_mtu_cached)
3790 pmtu = route_mtu_cached;
3791
3792 dst_metric_set(dst, RTAX_MTU, pmtu);
3793 }
3794 }
3795
3796 /* Check that the bundle accepts the flow and its components are
3797 * still valid.
3798 */
3799
xfrm_bundle_ok(struct xfrm_dst * first)3800 static int xfrm_bundle_ok(struct xfrm_dst *first)
3801 {
3802 struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3803 struct dst_entry *dst = &first->u.dst;
3804 struct xfrm_dst *xdst;
3805 int start_from, nr;
3806 u32 mtu;
3807
3808 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3809 (dst->dev && !netif_running(dst->dev)))
3810 return 0;
3811
3812 if (dst->flags & DST_XFRM_QUEUE)
3813 return 1;
3814
3815 start_from = nr = 0;
3816 do {
3817 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3818
3819 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3820 return 0;
3821 if (xdst->xfrm_genid != dst->xfrm->genid)
3822 return 0;
3823 if (xdst->num_pols > 0 &&
3824 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3825 return 0;
3826
3827 bundle[nr++] = xdst;
3828
3829 mtu = dst_mtu(xfrm_dst_child(dst));
3830 if (xdst->child_mtu_cached != mtu) {
3831 start_from = nr;
3832 xdst->child_mtu_cached = mtu;
3833 }
3834
3835 if (!dst_check(xdst->route, xdst->route_cookie))
3836 return 0;
3837 mtu = dst_mtu(xdst->route);
3838 if (xdst->route_mtu_cached != mtu) {
3839 start_from = nr;
3840 xdst->route_mtu_cached = mtu;
3841 }
3842
3843 dst = xfrm_dst_child(dst);
3844 } while (dst->xfrm);
3845
3846 if (likely(!start_from))
3847 return 1;
3848
3849 xdst = bundle[start_from - 1];
3850 mtu = xdst->child_mtu_cached;
3851 while (start_from--) {
3852 dst = &xdst->u.dst;
3853
3854 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3855 if (mtu > xdst->route_mtu_cached)
3856 mtu = xdst->route_mtu_cached;
3857 dst_metric_set(dst, RTAX_MTU, mtu);
3858 if (!start_from)
3859 break;
3860
3861 xdst = bundle[start_from - 1];
3862 xdst->child_mtu_cached = mtu;
3863 }
3864
3865 return 1;
3866 }
3867
xfrm_default_advmss(const struct dst_entry * dst)3868 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3869 {
3870 return dst_metric_advmss(xfrm_dst_path(dst));
3871 }
3872
xfrm_mtu(const struct dst_entry * dst)3873 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3874 {
3875 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3876
3877 return mtu ? : dst_mtu(xfrm_dst_path(dst));
3878 }
3879
xfrm_get_dst_nexthop(const struct dst_entry * dst,const void * daddr)3880 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3881 const void *daddr)
3882 {
3883 while (dst->xfrm) {
3884 const struct xfrm_state *xfrm = dst->xfrm;
3885
3886 dst = xfrm_dst_child(dst);
3887
3888 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3889 continue;
3890 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3891 daddr = xfrm->coaddr;
3892 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3893 daddr = &xfrm->id.daddr;
3894 }
3895 return daddr;
3896 }
3897
xfrm_neigh_lookup(const struct dst_entry * dst,struct sk_buff * skb,const void * daddr)3898 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3899 struct sk_buff *skb,
3900 const void *daddr)
3901 {
3902 const struct dst_entry *path = xfrm_dst_path(dst);
3903
3904 if (!skb)
3905 daddr = xfrm_get_dst_nexthop(dst, daddr);
3906 return path->ops->neigh_lookup(path, skb, daddr);
3907 }
3908
xfrm_confirm_neigh(const struct dst_entry * dst,const void * daddr)3909 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3910 {
3911 const struct dst_entry *path = xfrm_dst_path(dst);
3912
3913 daddr = xfrm_get_dst_nexthop(dst, daddr);
3914 path->ops->confirm_neigh(path, daddr);
3915 }
3916
xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo * afinfo,int family)3917 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3918 {
3919 int err = 0;
3920
3921 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3922 return -EAFNOSUPPORT;
3923
3924 spin_lock(&xfrm_policy_afinfo_lock);
3925 if (unlikely(xfrm_policy_afinfo[family] != NULL))
3926 err = -EEXIST;
3927 else {
3928 struct dst_ops *dst_ops = afinfo->dst_ops;
3929 if (likely(dst_ops->kmem_cachep == NULL))
3930 dst_ops->kmem_cachep = xfrm_dst_cache;
3931 if (likely(dst_ops->check == NULL))
3932 dst_ops->check = xfrm_dst_check;
3933 if (likely(dst_ops->default_advmss == NULL))
3934 dst_ops->default_advmss = xfrm_default_advmss;
3935 if (likely(dst_ops->mtu == NULL))
3936 dst_ops->mtu = xfrm_mtu;
3937 if (likely(dst_ops->negative_advice == NULL))
3938 dst_ops->negative_advice = xfrm_negative_advice;
3939 if (likely(dst_ops->link_failure == NULL))
3940 dst_ops->link_failure = xfrm_link_failure;
3941 if (likely(dst_ops->neigh_lookup == NULL))
3942 dst_ops->neigh_lookup = xfrm_neigh_lookup;
3943 if (likely(!dst_ops->confirm_neigh))
3944 dst_ops->confirm_neigh = xfrm_confirm_neigh;
3945 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
3946 }
3947 spin_unlock(&xfrm_policy_afinfo_lock);
3948
3949 return err;
3950 }
3951 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
3952
xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo * afinfo)3953 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
3954 {
3955 struct dst_ops *dst_ops = afinfo->dst_ops;
3956 int i;
3957
3958 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
3959 if (xfrm_policy_afinfo[i] != afinfo)
3960 continue;
3961 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
3962 break;
3963 }
3964
3965 synchronize_rcu();
3966
3967 dst_ops->kmem_cachep = NULL;
3968 dst_ops->check = NULL;
3969 dst_ops->negative_advice = NULL;
3970 dst_ops->link_failure = NULL;
3971 }
3972 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
3973
xfrm_if_register_cb(const struct xfrm_if_cb * ifcb)3974 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
3975 {
3976 spin_lock(&xfrm_if_cb_lock);
3977 rcu_assign_pointer(xfrm_if_cb, ifcb);
3978 spin_unlock(&xfrm_if_cb_lock);
3979 }
3980 EXPORT_SYMBOL(xfrm_if_register_cb);
3981
xfrm_if_unregister_cb(void)3982 void xfrm_if_unregister_cb(void)
3983 {
3984 RCU_INIT_POINTER(xfrm_if_cb, NULL);
3985 synchronize_rcu();
3986 }
3987 EXPORT_SYMBOL(xfrm_if_unregister_cb);
3988
3989 #ifdef CONFIG_XFRM_STATISTICS
xfrm_statistics_init(struct net * net)3990 static int __net_init xfrm_statistics_init(struct net *net)
3991 {
3992 int rv;
3993 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
3994 if (!net->mib.xfrm_statistics)
3995 return -ENOMEM;
3996 rv = xfrm_proc_init(net);
3997 if (rv < 0)
3998 free_percpu(net->mib.xfrm_statistics);
3999 return rv;
4000 }
4001
xfrm_statistics_fini(struct net * net)4002 static void xfrm_statistics_fini(struct net *net)
4003 {
4004 xfrm_proc_fini(net);
4005 free_percpu(net->mib.xfrm_statistics);
4006 }
4007 #else
xfrm_statistics_init(struct net * net)4008 static int __net_init xfrm_statistics_init(struct net *net)
4009 {
4010 return 0;
4011 }
4012
xfrm_statistics_fini(struct net * net)4013 static void xfrm_statistics_fini(struct net *net)
4014 {
4015 }
4016 #endif
4017
xfrm_policy_init(struct net * net)4018 static int __net_init xfrm_policy_init(struct net *net)
4019 {
4020 unsigned int hmask, sz;
4021 int dir, err;
4022
4023 if (net_eq(net, &init_net)) {
4024 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4025 sizeof(struct xfrm_dst),
4026 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4027 NULL);
4028 err = rhashtable_init(&xfrm_policy_inexact_table,
4029 &xfrm_pol_inexact_params);
4030 BUG_ON(err);
4031 }
4032
4033 hmask = 8 - 1;
4034 sz = (hmask+1) * sizeof(struct hlist_head);
4035
4036 net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4037 if (!net->xfrm.policy_byidx)
4038 goto out_byidx;
4039 net->xfrm.policy_idx_hmask = hmask;
4040
4041 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4042 struct xfrm_policy_hash *htab;
4043
4044 net->xfrm.policy_count[dir] = 0;
4045 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4046 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4047
4048 htab = &net->xfrm.policy_bydst[dir];
4049 htab->table = xfrm_hash_alloc(sz);
4050 if (!htab->table)
4051 goto out_bydst;
4052 htab->hmask = hmask;
4053 htab->dbits4 = 32;
4054 htab->sbits4 = 32;
4055 htab->dbits6 = 128;
4056 htab->sbits6 = 128;
4057 }
4058 net->xfrm.policy_hthresh.lbits4 = 32;
4059 net->xfrm.policy_hthresh.rbits4 = 32;
4060 net->xfrm.policy_hthresh.lbits6 = 128;
4061 net->xfrm.policy_hthresh.rbits6 = 128;
4062
4063 seqlock_init(&net->xfrm.policy_hthresh.lock);
4064
4065 INIT_LIST_HEAD(&net->xfrm.policy_all);
4066 INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4067 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4068 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4069 return 0;
4070
4071 out_bydst:
4072 for (dir--; dir >= 0; dir--) {
4073 struct xfrm_policy_hash *htab;
4074
4075 htab = &net->xfrm.policy_bydst[dir];
4076 xfrm_hash_free(htab->table, sz);
4077 }
4078 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4079 out_byidx:
4080 return -ENOMEM;
4081 }
4082
xfrm_policy_fini(struct net * net)4083 static void xfrm_policy_fini(struct net *net)
4084 {
4085 struct xfrm_pol_inexact_bin *b, *t;
4086 unsigned int sz;
4087 int dir;
4088
4089 flush_work(&net->xfrm.policy_hash_work);
4090 #ifdef CONFIG_XFRM_SUB_POLICY
4091 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4092 #endif
4093 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4094
4095 WARN_ON(!list_empty(&net->xfrm.policy_all));
4096
4097 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4098 struct xfrm_policy_hash *htab;
4099
4100 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4101
4102 htab = &net->xfrm.policy_bydst[dir];
4103 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4104 WARN_ON(!hlist_empty(htab->table));
4105 xfrm_hash_free(htab->table, sz);
4106 }
4107
4108 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4109 WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4110 xfrm_hash_free(net->xfrm.policy_byidx, sz);
4111
4112 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4113 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4114 __xfrm_policy_inexact_prune_bin(b, true);
4115 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4116 }
4117
xfrm_net_init(struct net * net)4118 static int __net_init xfrm_net_init(struct net *net)
4119 {
4120 int rv;
4121
4122 /* Initialize the per-net locks here */
4123 spin_lock_init(&net->xfrm.xfrm_state_lock);
4124 spin_lock_init(&net->xfrm.xfrm_policy_lock);
4125 seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4126 mutex_init(&net->xfrm.xfrm_cfg_mutex);
4127 net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4128 net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4129 net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4130
4131 rv = xfrm_statistics_init(net);
4132 if (rv < 0)
4133 goto out_statistics;
4134 rv = xfrm_state_init(net);
4135 if (rv < 0)
4136 goto out_state;
4137 rv = xfrm_policy_init(net);
4138 if (rv < 0)
4139 goto out_policy;
4140 rv = xfrm_sysctl_init(net);
4141 if (rv < 0)
4142 goto out_sysctl;
4143
4144 return 0;
4145
4146 out_sysctl:
4147 xfrm_policy_fini(net);
4148 out_policy:
4149 xfrm_state_fini(net);
4150 out_state:
4151 xfrm_statistics_fini(net);
4152 out_statistics:
4153 return rv;
4154 }
4155
xfrm_net_exit(struct net * net)4156 static void __net_exit xfrm_net_exit(struct net *net)
4157 {
4158 xfrm_sysctl_fini(net);
4159 xfrm_policy_fini(net);
4160 xfrm_state_fini(net);
4161 xfrm_statistics_fini(net);
4162 }
4163
4164 static struct pernet_operations __net_initdata xfrm_net_ops = {
4165 .init = xfrm_net_init,
4166 .exit = xfrm_net_exit,
4167 };
4168
xfrm_init(void)4169 void __init xfrm_init(void)
4170 {
4171 register_pernet_subsys(&xfrm_net_ops);
4172 xfrm_dev_init();
4173 xfrm_input_init();
4174
4175 #ifdef CONFIG_XFRM_ESPINTCP
4176 espintcp_init();
4177 #endif
4178 }
4179
4180 #ifdef CONFIG_AUDITSYSCALL
xfrm_audit_common_policyinfo(struct xfrm_policy * xp,struct audit_buffer * audit_buf)4181 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4182 struct audit_buffer *audit_buf)
4183 {
4184 struct xfrm_sec_ctx *ctx = xp->security;
4185 struct xfrm_selector *sel = &xp->selector;
4186
4187 if (ctx)
4188 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4189 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4190
4191 switch (sel->family) {
4192 case AF_INET:
4193 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4194 if (sel->prefixlen_s != 32)
4195 audit_log_format(audit_buf, " src_prefixlen=%d",
4196 sel->prefixlen_s);
4197 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4198 if (sel->prefixlen_d != 32)
4199 audit_log_format(audit_buf, " dst_prefixlen=%d",
4200 sel->prefixlen_d);
4201 break;
4202 case AF_INET6:
4203 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4204 if (sel->prefixlen_s != 128)
4205 audit_log_format(audit_buf, " src_prefixlen=%d",
4206 sel->prefixlen_s);
4207 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4208 if (sel->prefixlen_d != 128)
4209 audit_log_format(audit_buf, " dst_prefixlen=%d",
4210 sel->prefixlen_d);
4211 break;
4212 }
4213 }
4214
xfrm_audit_policy_add(struct xfrm_policy * xp,int result,bool task_valid)4215 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4216 {
4217 struct audit_buffer *audit_buf;
4218
4219 audit_buf = xfrm_audit_start("SPD-add");
4220 if (audit_buf == NULL)
4221 return;
4222 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4223 audit_log_format(audit_buf, " res=%u", result);
4224 xfrm_audit_common_policyinfo(xp, audit_buf);
4225 audit_log_end(audit_buf);
4226 }
4227 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4228
xfrm_audit_policy_delete(struct xfrm_policy * xp,int result,bool task_valid)4229 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4230 bool task_valid)
4231 {
4232 struct audit_buffer *audit_buf;
4233
4234 audit_buf = xfrm_audit_start("SPD-delete");
4235 if (audit_buf == NULL)
4236 return;
4237 xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4238 audit_log_format(audit_buf, " res=%u", result);
4239 xfrm_audit_common_policyinfo(xp, audit_buf);
4240 audit_log_end(audit_buf);
4241 }
4242 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4243 #endif
4244
4245 #ifdef CONFIG_XFRM_MIGRATE
xfrm_migrate_selector_match(const struct xfrm_selector * sel_cmp,const struct xfrm_selector * sel_tgt)4246 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4247 const struct xfrm_selector *sel_tgt)
4248 {
4249 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4250 if (sel_tgt->family == sel_cmp->family &&
4251 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4252 sel_cmp->family) &&
4253 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4254 sel_cmp->family) &&
4255 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4256 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4257 return true;
4258 }
4259 } else {
4260 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4261 return true;
4262 }
4263 }
4264 return false;
4265 }
4266
xfrm_migrate_policy_find(const struct xfrm_selector * sel,u8 dir,u8 type,struct net * net,u32 if_id)4267 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4268 u8 dir, u8 type, struct net *net, u32 if_id)
4269 {
4270 struct xfrm_policy *pol, *ret = NULL;
4271 struct hlist_head *chain;
4272 u32 priority = ~0U;
4273
4274 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4275 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4276 hlist_for_each_entry(pol, chain, bydst) {
4277 if ((if_id == 0 || pol->if_id == if_id) &&
4278 xfrm_migrate_selector_match(sel, &pol->selector) &&
4279 pol->type == type) {
4280 ret = pol;
4281 priority = ret->priority;
4282 break;
4283 }
4284 }
4285 chain = &net->xfrm.policy_inexact[dir];
4286 hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4287 if ((pol->priority >= priority) && ret)
4288 break;
4289
4290 if ((if_id == 0 || pol->if_id == if_id) &&
4291 xfrm_migrate_selector_match(sel, &pol->selector) &&
4292 pol->type == type) {
4293 ret = pol;
4294 break;
4295 }
4296 }
4297
4298 xfrm_pol_hold(ret);
4299
4300 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4301
4302 return ret;
4303 }
4304
migrate_tmpl_match(const struct xfrm_migrate * m,const struct xfrm_tmpl * t)4305 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4306 {
4307 int match = 0;
4308
4309 if (t->mode == m->mode && t->id.proto == m->proto &&
4310 (m->reqid == 0 || t->reqid == m->reqid)) {
4311 switch (t->mode) {
4312 case XFRM_MODE_TUNNEL:
4313 case XFRM_MODE_BEET:
4314 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4315 m->old_family) &&
4316 xfrm_addr_equal(&t->saddr, &m->old_saddr,
4317 m->old_family)) {
4318 match = 1;
4319 }
4320 break;
4321 case XFRM_MODE_TRANSPORT:
4322 /* in case of transport mode, template does not store
4323 any IP addresses, hence we just compare mode and
4324 protocol */
4325 match = 1;
4326 break;
4327 default:
4328 break;
4329 }
4330 }
4331 return match;
4332 }
4333
4334 /* update endpoint address(es) of template(s) */
xfrm_policy_migrate(struct xfrm_policy * pol,struct xfrm_migrate * m,int num_migrate)4335 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4336 struct xfrm_migrate *m, int num_migrate)
4337 {
4338 struct xfrm_migrate *mp;
4339 int i, j, n = 0;
4340
4341 write_lock_bh(&pol->lock);
4342 if (unlikely(pol->walk.dead)) {
4343 /* target policy has been deleted */
4344 write_unlock_bh(&pol->lock);
4345 return -ENOENT;
4346 }
4347
4348 for (i = 0; i < pol->xfrm_nr; i++) {
4349 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4350 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4351 continue;
4352 n++;
4353 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4354 pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4355 continue;
4356 /* update endpoints */
4357 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4358 sizeof(pol->xfrm_vec[i].id.daddr));
4359 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4360 sizeof(pol->xfrm_vec[i].saddr));
4361 pol->xfrm_vec[i].encap_family = mp->new_family;
4362 /* flush bundles */
4363 atomic_inc(&pol->genid);
4364 }
4365 }
4366
4367 write_unlock_bh(&pol->lock);
4368
4369 if (!n)
4370 return -ENODATA;
4371
4372 return 0;
4373 }
4374
xfrm_migrate_check(const struct xfrm_migrate * m,int num_migrate)4375 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
4376 {
4377 int i, j;
4378
4379 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
4380 return -EINVAL;
4381
4382 for (i = 0; i < num_migrate; i++) {
4383 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4384 xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
4385 return -EINVAL;
4386
4387 /* check if there is any duplicated entry */
4388 for (j = i + 1; j < num_migrate; j++) {
4389 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4390 sizeof(m[i].old_daddr)) &&
4391 !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4392 sizeof(m[i].old_saddr)) &&
4393 m[i].proto == m[j].proto &&
4394 m[i].mode == m[j].mode &&
4395 m[i].reqid == m[j].reqid &&
4396 m[i].old_family == m[j].old_family)
4397 return -EINVAL;
4398 }
4399 }
4400
4401 return 0;
4402 }
4403
xfrm_migrate(const struct xfrm_selector * sel,u8 dir,u8 type,struct xfrm_migrate * m,int num_migrate,struct xfrm_kmaddress * k,struct net * net,struct xfrm_encap_tmpl * encap,u32 if_id)4404 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4405 struct xfrm_migrate *m, int num_migrate,
4406 struct xfrm_kmaddress *k, struct net *net,
4407 struct xfrm_encap_tmpl *encap, u32 if_id)
4408 {
4409 int i, err, nx_cur = 0, nx_new = 0;
4410 struct xfrm_policy *pol = NULL;
4411 struct xfrm_state *x, *xc;
4412 struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4413 struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4414 struct xfrm_migrate *mp;
4415
4416 /* Stage 0 - sanity checks */
4417 if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
4418 goto out;
4419
4420 if (dir >= XFRM_POLICY_MAX) {
4421 err = -EINVAL;
4422 goto out;
4423 }
4424
4425 /* Stage 1 - find policy */
4426 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id)) == NULL) {
4427 err = -ENOENT;
4428 goto out;
4429 }
4430
4431 /* Stage 2 - find and update state(s) */
4432 for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4433 if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4434 x_cur[nx_cur] = x;
4435 nx_cur++;
4436 xc = xfrm_state_migrate(x, mp, encap);
4437 if (xc) {
4438 x_new[nx_new] = xc;
4439 nx_new++;
4440 } else {
4441 err = -ENODATA;
4442 goto restore_state;
4443 }
4444 }
4445 }
4446
4447 /* Stage 3 - update policy */
4448 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
4449 goto restore_state;
4450
4451 /* Stage 4 - delete old state(s) */
4452 if (nx_cur) {
4453 xfrm_states_put(x_cur, nx_cur);
4454 xfrm_states_delete(x_cur, nx_cur);
4455 }
4456
4457 /* Stage 5 - announce */
4458 km_migrate(sel, dir, type, m, num_migrate, k, encap);
4459
4460 xfrm_pol_put(pol);
4461
4462 return 0;
4463 out:
4464 return err;
4465
4466 restore_state:
4467 if (pol)
4468 xfrm_pol_put(pol);
4469 if (nx_cur)
4470 xfrm_states_put(x_cur, nx_cur);
4471 if (nx_new)
4472 xfrm_states_delete(x_new, nx_new);
4473
4474 return err;
4475 }
4476 EXPORT_SYMBOL(xfrm_migrate);
4477 #endif
4478