1 /* 2 * xfrm_policy.c 3 * 4 * Changes: 5 * Mitsuru KANDA @USAGI 6 * Kazunori MIYAZAWA @USAGI 7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 8 * IPv6 support 9 * Kazunori MIYAZAWA @USAGI 10 * YOSHIFUJI Hideaki 11 * Split up af-specific portion 12 * Derek Atkins <derek@ihtfp.com> Add the post_input processor 13 * 14 */ 15 16 #include <linux/err.h> 17 #include <linux/slab.h> 18 #include <linux/kmod.h> 19 #include <linux/list.h> 20 #include <linux/spinlock.h> 21 #include <linux/workqueue.h> 22 #include <linux/notifier.h> 23 #include <linux/netdevice.h> 24 #include <linux/netfilter.h> 25 #include <linux/module.h> 26 #include <linux/cache.h> 27 #include <linux/cpu.h> 28 #include <linux/audit.h> 29 #include <linux/rhashtable.h> 30 #include <linux/if_tunnel.h> 31 #include <net/dst.h> 32 #include <net/flow.h> 33 #include <net/xfrm.h> 34 #include <net/ip.h> 35 #if IS_ENABLED(CONFIG_IPV6_MIP6) 36 #include <net/mip6.h> 37 #endif 38 #ifdef CONFIG_XFRM_STATISTICS 39 #include <net/snmp.h> 40 #endif 41 42 #include "xfrm_hash.h" 43 44 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 45 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 46 #define XFRM_MAX_QUEUE_LEN 100 47 48 struct xfrm_flo { 49 struct dst_entry *dst_orig; 50 u8 flags; 51 }; 52 53 /* prefixes smaller than this are stored in lists, not trees. */ 54 #define INEXACT_PREFIXLEN_IPV4 16 55 #define INEXACT_PREFIXLEN_IPV6 48 56 57 struct xfrm_pol_inexact_node { 58 struct rb_node node; 59 union { 60 xfrm_address_t addr; 61 struct rcu_head rcu; 62 }; 63 u8 prefixlen; 64 65 struct rb_root root; 66 67 /* the policies matching this node, can be empty list */ 68 struct hlist_head hhead; 69 }; 70 71 /* xfrm inexact policy search tree: 72 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id); 73 * | 74 * +---- root_d: sorted by daddr:prefix 75 * | | 76 * | xfrm_pol_inexact_node 77 * | | 78 * | +- root: sorted by saddr/prefix 79 * | | | 80 * | | xfrm_pol_inexact_node 81 * | | | 82 * | | + root: unused 83 * | | | 84 * | | + hhead: saddr:daddr policies 85 * | | 86 * | +- coarse policies and all any:daddr policies 87 * | 88 * +---- root_s: sorted by saddr:prefix 89 * | | 90 * | xfrm_pol_inexact_node 91 * | | 92 * | + root: unused 93 * | | 94 * | + hhead: saddr:any policies 95 * | 96 * +---- coarse policies and all any:any policies 97 * 98 * Lookups return four candidate lists: 99 * 1. any:any list from top-level xfrm_pol_inexact_bin 100 * 2. any:daddr list from daddr tree 101 * 3. saddr:daddr list from 2nd level daddr tree 102 * 4. saddr:any list from saddr tree 103 * 104 * This result set then needs to be searched for the policy with 105 * the lowest priority. If two results have same prio, youngest one wins. 106 */ 107 108 struct xfrm_pol_inexact_key { 109 possible_net_t net; 110 u32 if_id; 111 u16 family; 112 u8 dir, type; 113 }; 114 115 struct xfrm_pol_inexact_bin { 116 struct xfrm_pol_inexact_key k; 117 struct rhash_head head; 118 /* list containing '*:*' policies */ 119 struct hlist_head hhead; 120 121 seqcount_t count; 122 /* tree sorted by daddr/prefix */ 123 struct rb_root root_d; 124 125 /* tree sorted by saddr/prefix */ 126 struct rb_root root_s; 127 128 /* slow path below */ 129 struct list_head inexact_bins; 130 struct rcu_head rcu; 131 }; 132 133 enum xfrm_pol_inexact_candidate_type { 134 XFRM_POL_CAND_BOTH, 135 XFRM_POL_CAND_SADDR, 136 XFRM_POL_CAND_DADDR, 137 XFRM_POL_CAND_ANY, 138 139 XFRM_POL_CAND_MAX, 140 }; 141 142 struct xfrm_pol_inexact_candidates { 143 struct hlist_head *res[XFRM_POL_CAND_MAX]; 144 }; 145 146 static DEFINE_SPINLOCK(xfrm_if_cb_lock); 147 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 148 149 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 150 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 151 __read_mostly; 152 153 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 154 static __read_mostly seqcount_t xfrm_policy_hash_generation; 155 156 static struct rhashtable xfrm_policy_inexact_table; 157 static const struct rhashtable_params xfrm_pol_inexact_params; 158 159 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 160 static int stale_bundle(struct dst_entry *dst); 161 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 162 static void xfrm_policy_queue_process(struct timer_list *t); 163 164 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 165 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 166 int dir); 167 168 static struct xfrm_pol_inexact_bin * 169 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, 170 u32 if_id); 171 172 static struct xfrm_pol_inexact_bin * 173 xfrm_policy_inexact_lookup_rcu(struct net *net, 174 u8 type, u16 family, u8 dir, u32 if_id); 175 static struct xfrm_policy * 176 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, 177 bool excl); 178 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 179 struct xfrm_policy *policy); 180 181 static bool 182 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 183 struct xfrm_pol_inexact_bin *b, 184 const xfrm_address_t *saddr, 185 const xfrm_address_t *daddr); 186 187 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 188 { 189 return refcount_inc_not_zero(&policy->refcnt); 190 } 191 192 static inline bool 193 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 194 { 195 const struct flowi4 *fl4 = &fl->u.ip4; 196 197 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 198 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 199 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 200 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 201 (fl4->flowi4_proto == sel->proto || !sel->proto) && 202 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 203 } 204 205 static inline bool 206 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 207 { 208 const struct flowi6 *fl6 = &fl->u.ip6; 209 210 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 211 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 212 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 213 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 214 (fl6->flowi6_proto == sel->proto || !sel->proto) && 215 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 216 } 217 218 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 219 unsigned short family) 220 { 221 switch (family) { 222 case AF_INET: 223 return __xfrm4_selector_match(sel, fl); 224 case AF_INET6: 225 return __xfrm6_selector_match(sel, fl); 226 } 227 return false; 228 } 229 230 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 231 { 232 const struct xfrm_policy_afinfo *afinfo; 233 234 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 235 return NULL; 236 rcu_read_lock(); 237 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 238 if (unlikely(!afinfo)) 239 rcu_read_unlock(); 240 return afinfo; 241 } 242 243 /* Called with rcu_read_lock(). */ 244 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 245 { 246 return rcu_dereference(xfrm_if_cb); 247 } 248 249 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 250 const xfrm_address_t *saddr, 251 const xfrm_address_t *daddr, 252 int family, u32 mark) 253 { 254 const struct xfrm_policy_afinfo *afinfo; 255 struct dst_entry *dst; 256 257 afinfo = xfrm_policy_get_afinfo(family); 258 if (unlikely(afinfo == NULL)) 259 return ERR_PTR(-EAFNOSUPPORT); 260 261 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 262 263 rcu_read_unlock(); 264 265 return dst; 266 } 267 EXPORT_SYMBOL(__xfrm_dst_lookup); 268 269 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 270 int tos, int oif, 271 xfrm_address_t *prev_saddr, 272 xfrm_address_t *prev_daddr, 273 int family, u32 mark) 274 { 275 struct net *net = xs_net(x); 276 xfrm_address_t *saddr = &x->props.saddr; 277 xfrm_address_t *daddr = &x->id.daddr; 278 struct dst_entry *dst; 279 280 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 281 saddr = x->coaddr; 282 daddr = prev_daddr; 283 } 284 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 285 saddr = prev_saddr; 286 daddr = x->coaddr; 287 } 288 289 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 290 291 if (!IS_ERR(dst)) { 292 if (prev_saddr != saddr) 293 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 294 if (prev_daddr != daddr) 295 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 296 } 297 298 return dst; 299 } 300 301 static inline unsigned long make_jiffies(long secs) 302 { 303 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 304 return MAX_SCHEDULE_TIMEOUT-1; 305 else 306 return secs*HZ; 307 } 308 309 static void xfrm_policy_timer(struct timer_list *t) 310 { 311 struct xfrm_policy *xp = from_timer(xp, t, timer); 312 time64_t now = ktime_get_real_seconds(); 313 time64_t next = TIME64_MAX; 314 int warn = 0; 315 int dir; 316 317 read_lock(&xp->lock); 318 319 if (unlikely(xp->walk.dead)) 320 goto out; 321 322 dir = xfrm_policy_id2dir(xp->index); 323 324 if (xp->lft.hard_add_expires_seconds) { 325 time64_t tmo = xp->lft.hard_add_expires_seconds + 326 xp->curlft.add_time - now; 327 if (tmo <= 0) 328 goto expired; 329 if (tmo < next) 330 next = tmo; 331 } 332 if (xp->lft.hard_use_expires_seconds) { 333 time64_t tmo = xp->lft.hard_use_expires_seconds + 334 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 335 if (tmo <= 0) 336 goto expired; 337 if (tmo < next) 338 next = tmo; 339 } 340 if (xp->lft.soft_add_expires_seconds) { 341 time64_t tmo = xp->lft.soft_add_expires_seconds + 342 xp->curlft.add_time - now; 343 if (tmo <= 0) { 344 warn = 1; 345 tmo = XFRM_KM_TIMEOUT; 346 } 347 if (tmo < next) 348 next = tmo; 349 } 350 if (xp->lft.soft_use_expires_seconds) { 351 time64_t tmo = xp->lft.soft_use_expires_seconds + 352 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 353 if (tmo <= 0) { 354 warn = 1; 355 tmo = XFRM_KM_TIMEOUT; 356 } 357 if (tmo < next) 358 next = tmo; 359 } 360 361 if (warn) 362 km_policy_expired(xp, dir, 0, 0); 363 if (next != TIME64_MAX && 364 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 365 xfrm_pol_hold(xp); 366 367 out: 368 read_unlock(&xp->lock); 369 xfrm_pol_put(xp); 370 return; 371 372 expired: 373 read_unlock(&xp->lock); 374 if (!xfrm_policy_delete(xp, dir)) 375 km_policy_expired(xp, dir, 1, 0); 376 xfrm_pol_put(xp); 377 } 378 379 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 380 * SPD calls. 381 */ 382 383 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 384 { 385 struct xfrm_policy *policy; 386 387 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 388 389 if (policy) { 390 write_pnet(&policy->xp_net, net); 391 INIT_LIST_HEAD(&policy->walk.all); 392 INIT_HLIST_NODE(&policy->bydst_inexact_list); 393 INIT_HLIST_NODE(&policy->bydst); 394 INIT_HLIST_NODE(&policy->byidx); 395 rwlock_init(&policy->lock); 396 refcount_set(&policy->refcnt, 1); 397 skb_queue_head_init(&policy->polq.hold_queue); 398 timer_setup(&policy->timer, xfrm_policy_timer, 0); 399 timer_setup(&policy->polq.hold_timer, 400 xfrm_policy_queue_process, 0); 401 } 402 return policy; 403 } 404 EXPORT_SYMBOL(xfrm_policy_alloc); 405 406 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 407 { 408 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 409 410 security_xfrm_policy_free(policy->security); 411 kfree(policy); 412 } 413 414 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 415 416 void xfrm_policy_destroy(struct xfrm_policy *policy) 417 { 418 BUG_ON(!policy->walk.dead); 419 420 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 421 BUG(); 422 423 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 424 } 425 EXPORT_SYMBOL(xfrm_policy_destroy); 426 427 /* Rule must be locked. Release descendant resources, announce 428 * entry dead. The rule must be unlinked from lists to the moment. 429 */ 430 431 static void xfrm_policy_kill(struct xfrm_policy *policy) 432 { 433 policy->walk.dead = 1; 434 435 atomic_inc(&policy->genid); 436 437 if (del_timer(&policy->polq.hold_timer)) 438 xfrm_pol_put(policy); 439 skb_queue_purge(&policy->polq.hold_queue); 440 441 if (del_timer(&policy->timer)) 442 xfrm_pol_put(policy); 443 444 xfrm_pol_put(policy); 445 } 446 447 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 448 449 static inline unsigned int idx_hash(struct net *net, u32 index) 450 { 451 return __idx_hash(index, net->xfrm.policy_idx_hmask); 452 } 453 454 /* calculate policy hash thresholds */ 455 static void __get_hash_thresh(struct net *net, 456 unsigned short family, int dir, 457 u8 *dbits, u8 *sbits) 458 { 459 switch (family) { 460 case AF_INET: 461 *dbits = net->xfrm.policy_bydst[dir].dbits4; 462 *sbits = net->xfrm.policy_bydst[dir].sbits4; 463 break; 464 465 case AF_INET6: 466 *dbits = net->xfrm.policy_bydst[dir].dbits6; 467 *sbits = net->xfrm.policy_bydst[dir].sbits6; 468 break; 469 470 default: 471 *dbits = 0; 472 *sbits = 0; 473 } 474 } 475 476 static struct hlist_head *policy_hash_bysel(struct net *net, 477 const struct xfrm_selector *sel, 478 unsigned short family, int dir) 479 { 480 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 481 unsigned int hash; 482 u8 dbits; 483 u8 sbits; 484 485 __get_hash_thresh(net, family, dir, &dbits, &sbits); 486 hash = __sel_hash(sel, family, hmask, dbits, sbits); 487 488 if (hash == hmask + 1) 489 return NULL; 490 491 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 492 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 493 } 494 495 static struct hlist_head *policy_hash_direct(struct net *net, 496 const xfrm_address_t *daddr, 497 const xfrm_address_t *saddr, 498 unsigned short family, int dir) 499 { 500 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 501 unsigned int hash; 502 u8 dbits; 503 u8 sbits; 504 505 __get_hash_thresh(net, family, dir, &dbits, &sbits); 506 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 507 508 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 509 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 510 } 511 512 static void xfrm_dst_hash_transfer(struct net *net, 513 struct hlist_head *list, 514 struct hlist_head *ndsttable, 515 unsigned int nhashmask, 516 int dir) 517 { 518 struct hlist_node *tmp, *entry0 = NULL; 519 struct xfrm_policy *pol; 520 unsigned int h0 = 0; 521 u8 dbits; 522 u8 sbits; 523 524 redo: 525 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 526 unsigned int h; 527 528 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 529 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 530 pol->family, nhashmask, dbits, sbits); 531 if (!entry0) { 532 hlist_del_rcu(&pol->bydst); 533 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 534 h0 = h; 535 } else { 536 if (h != h0) 537 continue; 538 hlist_del_rcu(&pol->bydst); 539 hlist_add_behind_rcu(&pol->bydst, entry0); 540 } 541 entry0 = &pol->bydst; 542 } 543 if (!hlist_empty(list)) { 544 entry0 = NULL; 545 goto redo; 546 } 547 } 548 549 static void xfrm_idx_hash_transfer(struct hlist_head *list, 550 struct hlist_head *nidxtable, 551 unsigned int nhashmask) 552 { 553 struct hlist_node *tmp; 554 struct xfrm_policy *pol; 555 556 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 557 unsigned int h; 558 559 h = __idx_hash(pol->index, nhashmask); 560 hlist_add_head(&pol->byidx, nidxtable+h); 561 } 562 } 563 564 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 565 { 566 return ((old_hmask + 1) << 1) - 1; 567 } 568 569 static void xfrm_bydst_resize(struct net *net, int dir) 570 { 571 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 572 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 573 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 574 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 575 struct hlist_head *odst; 576 int i; 577 578 if (!ndst) 579 return; 580 581 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 582 write_seqcount_begin(&xfrm_policy_hash_generation); 583 584 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 585 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 586 587 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 588 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 589 590 for (i = hmask; i >= 0; i--) 591 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 592 593 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 594 net->xfrm.policy_bydst[dir].hmask = nhashmask; 595 596 write_seqcount_end(&xfrm_policy_hash_generation); 597 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 598 599 synchronize_rcu(); 600 601 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 602 } 603 604 static void xfrm_byidx_resize(struct net *net, int total) 605 { 606 unsigned int hmask = net->xfrm.policy_idx_hmask; 607 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 608 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 609 struct hlist_head *oidx = net->xfrm.policy_byidx; 610 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 611 int i; 612 613 if (!nidx) 614 return; 615 616 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 617 618 for (i = hmask; i >= 0; i--) 619 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 620 621 net->xfrm.policy_byidx = nidx; 622 net->xfrm.policy_idx_hmask = nhashmask; 623 624 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 625 626 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 627 } 628 629 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 630 { 631 unsigned int cnt = net->xfrm.policy_count[dir]; 632 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 633 634 if (total) 635 *total += cnt; 636 637 if ((hmask + 1) < xfrm_policy_hashmax && 638 cnt > hmask) 639 return 1; 640 641 return 0; 642 } 643 644 static inline int xfrm_byidx_should_resize(struct net *net, int total) 645 { 646 unsigned int hmask = net->xfrm.policy_idx_hmask; 647 648 if ((hmask + 1) < xfrm_policy_hashmax && 649 total > hmask) 650 return 1; 651 652 return 0; 653 } 654 655 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 656 { 657 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 658 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 659 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 660 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 661 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 662 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 663 si->spdhcnt = net->xfrm.policy_idx_hmask; 664 si->spdhmcnt = xfrm_policy_hashmax; 665 } 666 EXPORT_SYMBOL(xfrm_spd_getinfo); 667 668 static DEFINE_MUTEX(hash_resize_mutex); 669 static void xfrm_hash_resize(struct work_struct *work) 670 { 671 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 672 int dir, total; 673 674 mutex_lock(&hash_resize_mutex); 675 676 total = 0; 677 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 678 if (xfrm_bydst_should_resize(net, dir, &total)) 679 xfrm_bydst_resize(net, dir); 680 } 681 if (xfrm_byidx_should_resize(net, total)) 682 xfrm_byidx_resize(net, total); 683 684 mutex_unlock(&hash_resize_mutex); 685 } 686 687 /* Make sure *pol can be inserted into fastbin. 688 * Useful to check that later insert requests will be sucessful 689 * (provided xfrm_policy_lock is held throughout). 690 */ 691 static struct xfrm_pol_inexact_bin * 692 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) 693 { 694 struct xfrm_pol_inexact_bin *bin, *prev; 695 struct xfrm_pol_inexact_key k = { 696 .family = pol->family, 697 .type = pol->type, 698 .dir = dir, 699 .if_id = pol->if_id, 700 }; 701 struct net *net = xp_net(pol); 702 703 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 704 705 write_pnet(&k.net, net); 706 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, 707 xfrm_pol_inexact_params); 708 if (bin) 709 return bin; 710 711 bin = kzalloc(sizeof(*bin), GFP_ATOMIC); 712 if (!bin) 713 return NULL; 714 715 bin->k = k; 716 INIT_HLIST_HEAD(&bin->hhead); 717 bin->root_d = RB_ROOT; 718 bin->root_s = RB_ROOT; 719 seqcount_init(&bin->count); 720 721 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, 722 &bin->k, &bin->head, 723 xfrm_pol_inexact_params); 724 if (!prev) { 725 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); 726 return bin; 727 } 728 729 kfree(bin); 730 731 return IS_ERR(prev) ? NULL : prev; 732 } 733 734 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, 735 int family, u8 prefixlen) 736 { 737 if (xfrm_addr_any(addr, family)) 738 return true; 739 740 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) 741 return true; 742 743 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) 744 return true; 745 746 return false; 747 } 748 749 static bool 750 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) 751 { 752 const xfrm_address_t *addr; 753 bool saddr_any, daddr_any; 754 u8 prefixlen; 755 756 addr = &policy->selector.saddr; 757 prefixlen = policy->selector.prefixlen_s; 758 759 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 760 policy->family, 761 prefixlen); 762 addr = &policy->selector.daddr; 763 prefixlen = policy->selector.prefixlen_d; 764 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 765 policy->family, 766 prefixlen); 767 return saddr_any && daddr_any; 768 } 769 770 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, 771 const xfrm_address_t *addr, u8 prefixlen) 772 { 773 node->addr = *addr; 774 node->prefixlen = prefixlen; 775 } 776 777 static struct xfrm_pol_inexact_node * 778 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) 779 { 780 struct xfrm_pol_inexact_node *node; 781 782 node = kzalloc(sizeof(*node), GFP_ATOMIC); 783 if (node) 784 xfrm_pol_inexact_node_init(node, addr, prefixlen); 785 786 return node; 787 } 788 789 static int xfrm_policy_addr_delta(const xfrm_address_t *a, 790 const xfrm_address_t *b, 791 u8 prefixlen, u16 family) 792 { 793 unsigned int pdw, pbi; 794 int delta = 0; 795 796 switch (family) { 797 case AF_INET: 798 if (sizeof(long) == 4 && prefixlen == 0) 799 return ntohl(a->a4) - ntohl(b->a4); 800 return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) - 801 (ntohl(b->a4) & ((~0UL << (32 - prefixlen)))); 802 case AF_INET6: 803 pdw = prefixlen >> 5; 804 pbi = prefixlen & 0x1f; 805 806 if (pdw) { 807 delta = memcmp(a->a6, b->a6, pdw << 2); 808 if (delta) 809 return delta; 810 } 811 if (pbi) { 812 u32 mask = ~0u << (32 - pbi); 813 814 delta = (ntohl(a->a6[pdw]) & mask) - 815 (ntohl(b->a6[pdw]) & mask); 816 } 817 break; 818 default: 819 break; 820 } 821 822 return delta; 823 } 824 825 static void xfrm_policy_inexact_list_reinsert(struct net *net, 826 struct xfrm_pol_inexact_node *n, 827 u16 family) 828 { 829 unsigned int matched_s, matched_d; 830 struct xfrm_policy *policy, *p; 831 832 matched_s = 0; 833 matched_d = 0; 834 835 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 836 struct hlist_node *newpos = NULL; 837 bool matches_s, matches_d; 838 839 if (!policy->bydst_reinsert) 840 continue; 841 842 WARN_ON_ONCE(policy->family != family); 843 844 policy->bydst_reinsert = false; 845 hlist_for_each_entry(p, &n->hhead, bydst) { 846 if (policy->priority > p->priority) 847 newpos = &p->bydst; 848 else if (policy->priority == p->priority && 849 policy->pos > p->pos) 850 newpos = &p->bydst; 851 else 852 break; 853 } 854 855 if (newpos) 856 hlist_add_behind_rcu(&policy->bydst, newpos); 857 else 858 hlist_add_head_rcu(&policy->bydst, &n->hhead); 859 860 /* paranoia checks follow. 861 * Check that the reinserted policy matches at least 862 * saddr or daddr for current node prefix. 863 * 864 * Matching both is fine, matching saddr in one policy 865 * (but not daddr) and then matching only daddr in another 866 * is a bug. 867 */ 868 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 869 &n->addr, 870 n->prefixlen, 871 family) == 0; 872 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 873 &n->addr, 874 n->prefixlen, 875 family) == 0; 876 if (matches_s && matches_d) 877 continue; 878 879 WARN_ON_ONCE(!matches_s && !matches_d); 880 if (matches_s) 881 matched_s++; 882 if (matches_d) 883 matched_d++; 884 WARN_ON_ONCE(matched_s && matched_d); 885 } 886 } 887 888 static void xfrm_policy_inexact_node_reinsert(struct net *net, 889 struct xfrm_pol_inexact_node *n, 890 struct rb_root *new, 891 u16 family) 892 { 893 struct xfrm_pol_inexact_node *node; 894 struct rb_node **p, *parent; 895 896 /* we should not have another subtree here */ 897 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 898 restart: 899 parent = NULL; 900 p = &new->rb_node; 901 while (*p) { 902 u8 prefixlen; 903 int delta; 904 905 parent = *p; 906 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 907 908 prefixlen = min(node->prefixlen, n->prefixlen); 909 910 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 911 prefixlen, family); 912 if (delta < 0) { 913 p = &parent->rb_left; 914 } else if (delta > 0) { 915 p = &parent->rb_right; 916 } else { 917 struct xfrm_policy *tmp; 918 919 hlist_for_each_entry(tmp, &n->hhead, bydst) { 920 tmp->bydst_reinsert = true; 921 hlist_del_rcu(&tmp->bydst); 922 } 923 924 xfrm_policy_inexact_list_reinsert(net, node, family); 925 926 if (node->prefixlen == n->prefixlen) { 927 kfree_rcu(n, rcu); 928 return; 929 } 930 931 rb_erase(*p, new); 932 kfree_rcu(n, rcu); 933 n = node; 934 n->prefixlen = prefixlen; 935 goto restart; 936 } 937 } 938 939 rb_link_node_rcu(&n->node, parent, p); 940 rb_insert_color(&n->node, new); 941 } 942 943 /* merge nodes v and n */ 944 static void xfrm_policy_inexact_node_merge(struct net *net, 945 struct xfrm_pol_inexact_node *v, 946 struct xfrm_pol_inexact_node *n, 947 u16 family) 948 { 949 struct xfrm_pol_inexact_node *node; 950 struct xfrm_policy *tmp; 951 struct rb_node *rnode; 952 953 /* To-be-merged node v has a subtree. 954 * 955 * Dismantle it and insert its nodes to n->root. 956 */ 957 while ((rnode = rb_first(&v->root)) != NULL) { 958 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 959 rb_erase(&node->node, &v->root); 960 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 961 family); 962 } 963 964 hlist_for_each_entry(tmp, &v->hhead, bydst) { 965 tmp->bydst_reinsert = true; 966 hlist_del_rcu(&tmp->bydst); 967 } 968 969 xfrm_policy_inexact_list_reinsert(net, n, family); 970 } 971 972 static struct xfrm_pol_inexact_node * 973 xfrm_policy_inexact_insert_node(struct net *net, 974 struct rb_root *root, 975 xfrm_address_t *addr, 976 u16 family, u8 prefixlen, u8 dir) 977 { 978 struct xfrm_pol_inexact_node *cached = NULL; 979 struct rb_node **p, *parent = NULL; 980 struct xfrm_pol_inexact_node *node; 981 982 p = &root->rb_node; 983 while (*p) { 984 int delta; 985 986 parent = *p; 987 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 988 989 delta = xfrm_policy_addr_delta(addr, &node->addr, 990 node->prefixlen, 991 family); 992 if (delta == 0 && prefixlen >= node->prefixlen) { 993 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 994 return node; 995 } 996 997 if (delta < 0) 998 p = &parent->rb_left; 999 else 1000 p = &parent->rb_right; 1001 1002 if (prefixlen < node->prefixlen) { 1003 delta = xfrm_policy_addr_delta(addr, &node->addr, 1004 prefixlen, 1005 family); 1006 if (delta) 1007 continue; 1008 1009 /* This node is a subnet of the new prefix. It needs 1010 * to be removed and re-inserted with the smaller 1011 * prefix and all nodes that are now also covered 1012 * by the reduced prefixlen. 1013 */ 1014 rb_erase(&node->node, root); 1015 1016 if (!cached) { 1017 xfrm_pol_inexact_node_init(node, addr, 1018 prefixlen); 1019 cached = node; 1020 } else { 1021 /* This node also falls within the new 1022 * prefixlen. Merge the to-be-reinserted 1023 * node and this one. 1024 */ 1025 xfrm_policy_inexact_node_merge(net, node, 1026 cached, family); 1027 kfree_rcu(node, rcu); 1028 } 1029 1030 /* restart */ 1031 p = &root->rb_node; 1032 parent = NULL; 1033 } 1034 } 1035 1036 node = cached; 1037 if (!node) { 1038 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1039 if (!node) 1040 return NULL; 1041 } 1042 1043 rb_link_node_rcu(&node->node, parent, p); 1044 rb_insert_color(&node->node, root); 1045 1046 return node; 1047 } 1048 1049 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1050 { 1051 struct xfrm_pol_inexact_node *node; 1052 struct rb_node *rn = rb_first(r); 1053 1054 while (rn) { 1055 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1056 1057 xfrm_policy_inexact_gc_tree(&node->root, rm); 1058 rn = rb_next(rn); 1059 1060 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1061 WARN_ON_ONCE(rm); 1062 continue; 1063 } 1064 1065 rb_erase(&node->node, r); 1066 kfree_rcu(node, rcu); 1067 } 1068 } 1069 1070 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1071 { 1072 write_seqcount_begin(&b->count); 1073 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1074 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1075 write_seqcount_end(&b->count); 1076 1077 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1078 !hlist_empty(&b->hhead)) { 1079 WARN_ON_ONCE(net_exit); 1080 return; 1081 } 1082 1083 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1084 xfrm_pol_inexact_params) == 0) { 1085 list_del(&b->inexact_bins); 1086 kfree_rcu(b, rcu); 1087 } 1088 } 1089 1090 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1091 { 1092 struct net *net = read_pnet(&b->k.net); 1093 1094 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1095 __xfrm_policy_inexact_prune_bin(b, false); 1096 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1097 } 1098 1099 static void __xfrm_policy_inexact_flush(struct net *net) 1100 { 1101 struct xfrm_pol_inexact_bin *bin, *t; 1102 1103 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1104 1105 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1106 __xfrm_policy_inexact_prune_bin(bin, false); 1107 } 1108 1109 static struct hlist_head * 1110 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1111 struct xfrm_policy *policy, u8 dir) 1112 { 1113 struct xfrm_pol_inexact_node *n; 1114 struct net *net; 1115 1116 net = xp_net(policy); 1117 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1118 1119 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1120 return &bin->hhead; 1121 1122 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1123 policy->family, 1124 policy->selector.prefixlen_d)) { 1125 write_seqcount_begin(&bin->count); 1126 n = xfrm_policy_inexact_insert_node(net, 1127 &bin->root_s, 1128 &policy->selector.saddr, 1129 policy->family, 1130 policy->selector.prefixlen_s, 1131 dir); 1132 write_seqcount_end(&bin->count); 1133 if (!n) 1134 return NULL; 1135 1136 return &n->hhead; 1137 } 1138 1139 /* daddr is fixed */ 1140 write_seqcount_begin(&bin->count); 1141 n = xfrm_policy_inexact_insert_node(net, 1142 &bin->root_d, 1143 &policy->selector.daddr, 1144 policy->family, 1145 policy->selector.prefixlen_d, dir); 1146 write_seqcount_end(&bin->count); 1147 if (!n) 1148 return NULL; 1149 1150 /* saddr is wildcard */ 1151 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1152 policy->family, 1153 policy->selector.prefixlen_s)) 1154 return &n->hhead; 1155 1156 write_seqcount_begin(&bin->count); 1157 n = xfrm_policy_inexact_insert_node(net, 1158 &n->root, 1159 &policy->selector.saddr, 1160 policy->family, 1161 policy->selector.prefixlen_s, dir); 1162 write_seqcount_end(&bin->count); 1163 if (!n) 1164 return NULL; 1165 1166 return &n->hhead; 1167 } 1168 1169 static struct xfrm_policy * 1170 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1171 { 1172 struct xfrm_pol_inexact_bin *bin; 1173 struct xfrm_policy *delpol; 1174 struct hlist_head *chain; 1175 struct net *net; 1176 1177 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1178 if (!bin) 1179 return ERR_PTR(-ENOMEM); 1180 1181 net = xp_net(policy); 1182 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1183 1184 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1185 if (!chain) { 1186 __xfrm_policy_inexact_prune_bin(bin, false); 1187 return ERR_PTR(-ENOMEM); 1188 } 1189 1190 delpol = xfrm_policy_insert_list(chain, policy, excl); 1191 if (delpol && excl) { 1192 __xfrm_policy_inexact_prune_bin(bin, false); 1193 return ERR_PTR(-EEXIST); 1194 } 1195 1196 chain = &net->xfrm.policy_inexact[dir]; 1197 xfrm_policy_insert_inexact_list(chain, policy); 1198 1199 if (delpol) 1200 __xfrm_policy_inexact_prune_bin(bin, false); 1201 1202 return delpol; 1203 } 1204 1205 static void xfrm_hash_rebuild(struct work_struct *work) 1206 { 1207 struct net *net = container_of(work, struct net, 1208 xfrm.policy_hthresh.work); 1209 unsigned int hmask; 1210 struct xfrm_policy *pol; 1211 struct xfrm_policy *policy; 1212 struct hlist_head *chain; 1213 struct hlist_head *odst; 1214 struct hlist_node *newpos; 1215 int i; 1216 int dir; 1217 unsigned seq; 1218 u8 lbits4, rbits4, lbits6, rbits6; 1219 1220 mutex_lock(&hash_resize_mutex); 1221 1222 /* read selector prefixlen thresholds */ 1223 do { 1224 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1225 1226 lbits4 = net->xfrm.policy_hthresh.lbits4; 1227 rbits4 = net->xfrm.policy_hthresh.rbits4; 1228 lbits6 = net->xfrm.policy_hthresh.lbits6; 1229 rbits6 = net->xfrm.policy_hthresh.rbits6; 1230 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1231 1232 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1233 write_seqcount_begin(&xfrm_policy_hash_generation); 1234 1235 /* make sure that we can insert the indirect policies again before 1236 * we start with destructive action. 1237 */ 1238 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1239 struct xfrm_pol_inexact_bin *bin; 1240 u8 dbits, sbits; 1241 1242 dir = xfrm_policy_id2dir(policy->index); 1243 if (policy->walk.dead || dir >= XFRM_POLICY_MAX) 1244 continue; 1245 1246 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1247 if (policy->family == AF_INET) { 1248 dbits = rbits4; 1249 sbits = lbits4; 1250 } else { 1251 dbits = rbits6; 1252 sbits = lbits6; 1253 } 1254 } else { 1255 if (policy->family == AF_INET) { 1256 dbits = lbits4; 1257 sbits = rbits4; 1258 } else { 1259 dbits = lbits6; 1260 sbits = rbits6; 1261 } 1262 } 1263 1264 if (policy->selector.prefixlen_d < dbits || 1265 policy->selector.prefixlen_s < sbits) 1266 continue; 1267 1268 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1269 if (!bin) 1270 goto out_unlock; 1271 1272 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1273 goto out_unlock; 1274 } 1275 1276 /* reset the bydst and inexact table in all directions */ 1277 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1278 struct hlist_node *n; 1279 1280 hlist_for_each_entry_safe(policy, n, 1281 &net->xfrm.policy_inexact[dir], 1282 bydst_inexact_list) 1283 hlist_del_init(&policy->bydst_inexact_list); 1284 1285 hmask = net->xfrm.policy_bydst[dir].hmask; 1286 odst = net->xfrm.policy_bydst[dir].table; 1287 for (i = hmask; i >= 0; i--) 1288 INIT_HLIST_HEAD(odst + i); 1289 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1290 /* dir out => dst = remote, src = local */ 1291 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1292 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1293 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1294 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1295 } else { 1296 /* dir in/fwd => dst = local, src = remote */ 1297 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1298 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1299 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1300 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1301 } 1302 } 1303 1304 /* re-insert all policies by order of creation */ 1305 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1306 if (policy->walk.dead) 1307 continue; 1308 dir = xfrm_policy_id2dir(policy->index); 1309 if (dir >= XFRM_POLICY_MAX) { 1310 /* skip socket policies */ 1311 continue; 1312 } 1313 newpos = NULL; 1314 chain = policy_hash_bysel(net, &policy->selector, 1315 policy->family, dir); 1316 1317 hlist_del_rcu(&policy->bydst); 1318 1319 if (!chain) { 1320 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1321 1322 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1323 continue; 1324 } 1325 1326 hlist_for_each_entry(pol, chain, bydst) { 1327 if (policy->priority >= pol->priority) 1328 newpos = &pol->bydst; 1329 else 1330 break; 1331 } 1332 if (newpos) 1333 hlist_add_behind_rcu(&policy->bydst, newpos); 1334 else 1335 hlist_add_head_rcu(&policy->bydst, chain); 1336 } 1337 1338 out_unlock: 1339 __xfrm_policy_inexact_flush(net); 1340 write_seqcount_end(&xfrm_policy_hash_generation); 1341 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1342 1343 mutex_unlock(&hash_resize_mutex); 1344 } 1345 1346 void xfrm_policy_hash_rebuild(struct net *net) 1347 { 1348 schedule_work(&net->xfrm.policy_hthresh.work); 1349 } 1350 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1351 1352 /* Generate new index... KAME seems to generate them ordered by cost 1353 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1354 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1355 { 1356 static u32 idx_generator; 1357 1358 for (;;) { 1359 struct hlist_head *list; 1360 struct xfrm_policy *p; 1361 u32 idx; 1362 int found; 1363 1364 if (!index) { 1365 idx = (idx_generator | dir); 1366 idx_generator += 8; 1367 } else { 1368 idx = index; 1369 index = 0; 1370 } 1371 1372 if (idx == 0) 1373 idx = 8; 1374 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1375 found = 0; 1376 hlist_for_each_entry(p, list, byidx) { 1377 if (p->index == idx) { 1378 found = 1; 1379 break; 1380 } 1381 } 1382 if (!found) 1383 return idx; 1384 } 1385 } 1386 1387 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1388 { 1389 u32 *p1 = (u32 *) s1; 1390 u32 *p2 = (u32 *) s2; 1391 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1392 int i; 1393 1394 for (i = 0; i < len; i++) { 1395 if (p1[i] != p2[i]) 1396 return 1; 1397 } 1398 1399 return 0; 1400 } 1401 1402 static void xfrm_policy_requeue(struct xfrm_policy *old, 1403 struct xfrm_policy *new) 1404 { 1405 struct xfrm_policy_queue *pq = &old->polq; 1406 struct sk_buff_head list; 1407 1408 if (skb_queue_empty(&pq->hold_queue)) 1409 return; 1410 1411 __skb_queue_head_init(&list); 1412 1413 spin_lock_bh(&pq->hold_queue.lock); 1414 skb_queue_splice_init(&pq->hold_queue, &list); 1415 if (del_timer(&pq->hold_timer)) 1416 xfrm_pol_put(old); 1417 spin_unlock_bh(&pq->hold_queue.lock); 1418 1419 pq = &new->polq; 1420 1421 spin_lock_bh(&pq->hold_queue.lock); 1422 skb_queue_splice(&list, &pq->hold_queue); 1423 pq->timeout = XFRM_QUEUE_TMO_MIN; 1424 if (!mod_timer(&pq->hold_timer, jiffies)) 1425 xfrm_pol_hold(new); 1426 spin_unlock_bh(&pq->hold_queue.lock); 1427 } 1428 1429 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 1430 struct xfrm_policy *pol) 1431 { 1432 u32 mark = policy->mark.v & policy->mark.m; 1433 1434 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 1435 return true; 1436 1437 if ((mark & pol->mark.m) == pol->mark.v && 1438 policy->priority == pol->priority) 1439 return true; 1440 1441 return false; 1442 } 1443 1444 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1445 { 1446 const struct xfrm_pol_inexact_key *k = data; 1447 u32 a = k->type << 24 | k->dir << 16 | k->family; 1448 1449 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1450 seed); 1451 } 1452 1453 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1454 { 1455 const struct xfrm_pol_inexact_bin *b = data; 1456 1457 return xfrm_pol_bin_key(&b->k, 0, seed); 1458 } 1459 1460 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1461 const void *ptr) 1462 { 1463 const struct xfrm_pol_inexact_key *key = arg->key; 1464 const struct xfrm_pol_inexact_bin *b = ptr; 1465 int ret; 1466 1467 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1468 return -1; 1469 1470 ret = b->k.dir ^ key->dir; 1471 if (ret) 1472 return ret; 1473 1474 ret = b->k.type ^ key->type; 1475 if (ret) 1476 return ret; 1477 1478 ret = b->k.family ^ key->family; 1479 if (ret) 1480 return ret; 1481 1482 return b->k.if_id ^ key->if_id; 1483 } 1484 1485 static const struct rhashtable_params xfrm_pol_inexact_params = { 1486 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1487 .hashfn = xfrm_pol_bin_key, 1488 .obj_hashfn = xfrm_pol_bin_obj, 1489 .obj_cmpfn = xfrm_pol_bin_cmp, 1490 .automatic_shrinking = true, 1491 }; 1492 1493 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1494 struct xfrm_policy *policy) 1495 { 1496 struct xfrm_policy *pol, *delpol = NULL; 1497 struct hlist_node *newpos = NULL; 1498 int i = 0; 1499 1500 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1501 if (pol->type == policy->type && 1502 pol->if_id == policy->if_id && 1503 !selector_cmp(&pol->selector, &policy->selector) && 1504 xfrm_policy_mark_match(policy, pol) && 1505 xfrm_sec_ctx_match(pol->security, policy->security) && 1506 !WARN_ON(delpol)) { 1507 delpol = pol; 1508 if (policy->priority > pol->priority) 1509 continue; 1510 } else if (policy->priority >= pol->priority) { 1511 newpos = &pol->bydst_inexact_list; 1512 continue; 1513 } 1514 if (delpol) 1515 break; 1516 } 1517 1518 if (newpos) 1519 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1520 else 1521 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1522 1523 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1524 pol->pos = i; 1525 i++; 1526 } 1527 } 1528 1529 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1530 struct xfrm_policy *policy, 1531 bool excl) 1532 { 1533 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1534 1535 hlist_for_each_entry(pol, chain, bydst) { 1536 if (pol->type == policy->type && 1537 pol->if_id == policy->if_id && 1538 !selector_cmp(&pol->selector, &policy->selector) && 1539 xfrm_policy_mark_match(policy, pol) && 1540 xfrm_sec_ctx_match(pol->security, policy->security) && 1541 !WARN_ON(delpol)) { 1542 if (excl) 1543 return ERR_PTR(-EEXIST); 1544 delpol = pol; 1545 if (policy->priority > pol->priority) 1546 continue; 1547 } else if (policy->priority >= pol->priority) { 1548 newpos = pol; 1549 continue; 1550 } 1551 if (delpol) 1552 break; 1553 } 1554 1555 if (newpos) 1556 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1557 else 1558 hlist_add_head_rcu(&policy->bydst, chain); 1559 1560 return delpol; 1561 } 1562 1563 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1564 { 1565 struct net *net = xp_net(policy); 1566 struct xfrm_policy *delpol; 1567 struct hlist_head *chain; 1568 1569 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1570 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1571 if (chain) 1572 delpol = xfrm_policy_insert_list(chain, policy, excl); 1573 else 1574 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1575 1576 if (IS_ERR(delpol)) { 1577 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1578 return PTR_ERR(delpol); 1579 } 1580 1581 __xfrm_policy_link(policy, dir); 1582 1583 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1584 if (policy->family == AF_INET) 1585 rt_genid_bump_ipv4(net); 1586 else 1587 rt_genid_bump_ipv6(net); 1588 1589 if (delpol) { 1590 xfrm_policy_requeue(delpol, policy); 1591 __xfrm_policy_unlink(delpol, dir); 1592 } 1593 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1594 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1595 policy->curlft.add_time = ktime_get_real_seconds(); 1596 policy->curlft.use_time = 0; 1597 if (!mod_timer(&policy->timer, jiffies + HZ)) 1598 xfrm_pol_hold(policy); 1599 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1600 1601 if (delpol) 1602 xfrm_policy_kill(delpol); 1603 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1604 schedule_work(&net->xfrm.policy_hash_work); 1605 1606 return 0; 1607 } 1608 EXPORT_SYMBOL(xfrm_policy_insert); 1609 1610 static struct xfrm_policy * 1611 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id, 1612 u8 type, int dir, 1613 struct xfrm_selector *sel, 1614 struct xfrm_sec_ctx *ctx) 1615 { 1616 struct xfrm_policy *pol; 1617 1618 if (!chain) 1619 return NULL; 1620 1621 hlist_for_each_entry(pol, chain, bydst) { 1622 if (pol->type == type && 1623 pol->if_id == if_id && 1624 (mark & pol->mark.m) == pol->mark.v && 1625 !selector_cmp(sel, &pol->selector) && 1626 xfrm_sec_ctx_match(ctx, pol->security)) 1627 return pol; 1628 } 1629 1630 return NULL; 1631 } 1632 1633 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id, 1634 u8 type, int dir, 1635 struct xfrm_selector *sel, 1636 struct xfrm_sec_ctx *ctx, int delete, 1637 int *err) 1638 { 1639 struct xfrm_pol_inexact_bin *bin = NULL; 1640 struct xfrm_policy *pol, *ret = NULL; 1641 struct hlist_head *chain; 1642 1643 *err = 0; 1644 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1645 chain = policy_hash_bysel(net, sel, sel->family, dir); 1646 if (!chain) { 1647 struct xfrm_pol_inexact_candidates cand; 1648 int i; 1649 1650 bin = xfrm_policy_inexact_lookup(net, type, 1651 sel->family, dir, if_id); 1652 if (!bin) { 1653 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1654 return NULL; 1655 } 1656 1657 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1658 &sel->saddr, 1659 &sel->daddr)) { 1660 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1661 return NULL; 1662 } 1663 1664 pol = NULL; 1665 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1666 struct xfrm_policy *tmp; 1667 1668 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1669 if_id, type, dir, 1670 sel, ctx); 1671 if (!tmp) 1672 continue; 1673 1674 if (!pol || tmp->pos < pol->pos) 1675 pol = tmp; 1676 } 1677 } else { 1678 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1679 sel, ctx); 1680 } 1681 1682 if (pol) { 1683 xfrm_pol_hold(pol); 1684 if (delete) { 1685 *err = security_xfrm_policy_delete(pol->security); 1686 if (*err) { 1687 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1688 return pol; 1689 } 1690 __xfrm_policy_unlink(pol, dir); 1691 } 1692 ret = pol; 1693 } 1694 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1695 1696 if (ret && delete) 1697 xfrm_policy_kill(ret); 1698 if (bin && delete) 1699 xfrm_policy_inexact_prune_bin(bin); 1700 return ret; 1701 } 1702 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1703 1704 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id, 1705 u8 type, int dir, u32 id, int delete, 1706 int *err) 1707 { 1708 struct xfrm_policy *pol, *ret; 1709 struct hlist_head *chain; 1710 1711 *err = -ENOENT; 1712 if (xfrm_policy_id2dir(id) != dir) 1713 return NULL; 1714 1715 *err = 0; 1716 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1717 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1718 ret = NULL; 1719 hlist_for_each_entry(pol, chain, byidx) { 1720 if (pol->type == type && pol->index == id && 1721 pol->if_id == if_id && 1722 (mark & pol->mark.m) == pol->mark.v) { 1723 xfrm_pol_hold(pol); 1724 if (delete) { 1725 *err = security_xfrm_policy_delete( 1726 pol->security); 1727 if (*err) { 1728 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1729 return pol; 1730 } 1731 __xfrm_policy_unlink(pol, dir); 1732 } 1733 ret = pol; 1734 break; 1735 } 1736 } 1737 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1738 1739 if (ret && delete) 1740 xfrm_policy_kill(ret); 1741 return ret; 1742 } 1743 EXPORT_SYMBOL(xfrm_policy_byid); 1744 1745 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1746 static inline int 1747 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1748 { 1749 struct xfrm_policy *pol; 1750 int err = 0; 1751 1752 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1753 if (pol->walk.dead || 1754 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1755 pol->type != type) 1756 continue; 1757 1758 err = security_xfrm_policy_delete(pol->security); 1759 if (err) { 1760 xfrm_audit_policy_delete(pol, 0, task_valid); 1761 return err; 1762 } 1763 } 1764 return err; 1765 } 1766 #else 1767 static inline int 1768 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1769 { 1770 return 0; 1771 } 1772 #endif 1773 1774 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1775 { 1776 int dir, err = 0, cnt = 0; 1777 struct xfrm_policy *pol; 1778 1779 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1780 1781 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1782 if (err) 1783 goto out; 1784 1785 again: 1786 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1787 dir = xfrm_policy_id2dir(pol->index); 1788 if (pol->walk.dead || 1789 dir >= XFRM_POLICY_MAX || 1790 pol->type != type) 1791 continue; 1792 1793 __xfrm_policy_unlink(pol, dir); 1794 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1795 cnt++; 1796 xfrm_audit_policy_delete(pol, 1, task_valid); 1797 xfrm_policy_kill(pol); 1798 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1799 goto again; 1800 } 1801 if (cnt) 1802 __xfrm_policy_inexact_flush(net); 1803 else 1804 err = -ESRCH; 1805 out: 1806 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1807 return err; 1808 } 1809 EXPORT_SYMBOL(xfrm_policy_flush); 1810 1811 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1812 int (*func)(struct xfrm_policy *, int, int, void*), 1813 void *data) 1814 { 1815 struct xfrm_policy *pol; 1816 struct xfrm_policy_walk_entry *x; 1817 int error = 0; 1818 1819 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1820 walk->type != XFRM_POLICY_TYPE_ANY) 1821 return -EINVAL; 1822 1823 if (list_empty(&walk->walk.all) && walk->seq != 0) 1824 return 0; 1825 1826 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1827 if (list_empty(&walk->walk.all)) 1828 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1829 else 1830 x = list_first_entry(&walk->walk.all, 1831 struct xfrm_policy_walk_entry, all); 1832 1833 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1834 if (x->dead) 1835 continue; 1836 pol = container_of(x, struct xfrm_policy, walk); 1837 if (walk->type != XFRM_POLICY_TYPE_ANY && 1838 walk->type != pol->type) 1839 continue; 1840 error = func(pol, xfrm_policy_id2dir(pol->index), 1841 walk->seq, data); 1842 if (error) { 1843 list_move_tail(&walk->walk.all, &x->all); 1844 goto out; 1845 } 1846 walk->seq++; 1847 } 1848 if (walk->seq == 0) { 1849 error = -ENOENT; 1850 goto out; 1851 } 1852 list_del_init(&walk->walk.all); 1853 out: 1854 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1855 return error; 1856 } 1857 EXPORT_SYMBOL(xfrm_policy_walk); 1858 1859 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1860 { 1861 INIT_LIST_HEAD(&walk->walk.all); 1862 walk->walk.dead = 1; 1863 walk->type = type; 1864 walk->seq = 0; 1865 } 1866 EXPORT_SYMBOL(xfrm_policy_walk_init); 1867 1868 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1869 { 1870 if (list_empty(&walk->walk.all)) 1871 return; 1872 1873 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1874 list_del(&walk->walk.all); 1875 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1876 } 1877 EXPORT_SYMBOL(xfrm_policy_walk_done); 1878 1879 /* 1880 * Find policy to apply to this flow. 1881 * 1882 * Returns 0 if policy found, else an -errno. 1883 */ 1884 static int xfrm_policy_match(const struct xfrm_policy *pol, 1885 const struct flowi *fl, 1886 u8 type, u16 family, int dir, u32 if_id) 1887 { 1888 const struct xfrm_selector *sel = &pol->selector; 1889 int ret = -ESRCH; 1890 bool match; 1891 1892 if (pol->family != family || 1893 pol->if_id != if_id || 1894 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1895 pol->type != type) 1896 return ret; 1897 1898 match = xfrm_selector_match(sel, fl, family); 1899 if (match) 1900 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1901 dir); 1902 return ret; 1903 } 1904 1905 static struct xfrm_pol_inexact_node * 1906 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1907 seqcount_t *count, 1908 const xfrm_address_t *addr, u16 family) 1909 { 1910 const struct rb_node *parent; 1911 int seq; 1912 1913 again: 1914 seq = read_seqcount_begin(count); 1915 1916 parent = rcu_dereference_raw(r->rb_node); 1917 while (parent) { 1918 struct xfrm_pol_inexact_node *node; 1919 int delta; 1920 1921 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1922 1923 delta = xfrm_policy_addr_delta(addr, &node->addr, 1924 node->prefixlen, family); 1925 if (delta < 0) { 1926 parent = rcu_dereference_raw(parent->rb_left); 1927 continue; 1928 } else if (delta > 0) { 1929 parent = rcu_dereference_raw(parent->rb_right); 1930 continue; 1931 } 1932 1933 return node; 1934 } 1935 1936 if (read_seqcount_retry(count, seq)) 1937 goto again; 1938 1939 return NULL; 1940 } 1941 1942 static bool 1943 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1944 struct xfrm_pol_inexact_bin *b, 1945 const xfrm_address_t *saddr, 1946 const xfrm_address_t *daddr) 1947 { 1948 struct xfrm_pol_inexact_node *n; 1949 u16 family; 1950 1951 if (!b) 1952 return false; 1953 1954 family = b->k.family; 1955 memset(cand, 0, sizeof(*cand)); 1956 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1957 1958 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1959 family); 1960 if (n) { 1961 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1962 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1963 family); 1964 if (n) 1965 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1966 } 1967 1968 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1969 family); 1970 if (n) 1971 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1972 1973 return true; 1974 } 1975 1976 static struct xfrm_pol_inexact_bin * 1977 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1978 u8 dir, u32 if_id) 1979 { 1980 struct xfrm_pol_inexact_key k = { 1981 .family = family, 1982 .type = type, 1983 .dir = dir, 1984 .if_id = if_id, 1985 }; 1986 1987 write_pnet(&k.net, net); 1988 1989 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1990 xfrm_pol_inexact_params); 1991 } 1992 1993 static struct xfrm_pol_inexact_bin * 1994 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 1995 u8 dir, u32 if_id) 1996 { 1997 struct xfrm_pol_inexact_bin *bin; 1998 1999 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2000 2001 rcu_read_lock(); 2002 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2003 rcu_read_unlock(); 2004 2005 return bin; 2006 } 2007 2008 static struct xfrm_policy * 2009 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2010 struct xfrm_policy *prefer, 2011 const struct flowi *fl, 2012 u8 type, u16 family, int dir, u32 if_id) 2013 { 2014 u32 priority = prefer ? prefer->priority : ~0u; 2015 struct xfrm_policy *pol; 2016 2017 if (!chain) 2018 return NULL; 2019 2020 hlist_for_each_entry_rcu(pol, chain, bydst) { 2021 int err; 2022 2023 if (pol->priority > priority) 2024 break; 2025 2026 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2027 if (err) { 2028 if (err != -ESRCH) 2029 return ERR_PTR(err); 2030 2031 continue; 2032 } 2033 2034 if (prefer) { 2035 /* matches. Is it older than *prefer? */ 2036 if (pol->priority == priority && 2037 prefer->pos < pol->pos) 2038 return prefer; 2039 } 2040 2041 return pol; 2042 } 2043 2044 return NULL; 2045 } 2046 2047 static struct xfrm_policy * 2048 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2049 struct xfrm_policy *prefer, 2050 const struct flowi *fl, 2051 u8 type, u16 family, int dir, u32 if_id) 2052 { 2053 struct xfrm_policy *tmp; 2054 int i; 2055 2056 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2057 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2058 prefer, 2059 fl, type, family, dir, 2060 if_id); 2061 if (!tmp) 2062 continue; 2063 2064 if (IS_ERR(tmp)) 2065 return tmp; 2066 prefer = tmp; 2067 } 2068 2069 return prefer; 2070 } 2071 2072 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2073 const struct flowi *fl, 2074 u16 family, u8 dir, 2075 u32 if_id) 2076 { 2077 struct xfrm_pol_inexact_candidates cand; 2078 const xfrm_address_t *daddr, *saddr; 2079 struct xfrm_pol_inexact_bin *bin; 2080 struct xfrm_policy *pol, *ret; 2081 struct hlist_head *chain; 2082 unsigned int sequence; 2083 int err; 2084 2085 daddr = xfrm_flowi_daddr(fl, family); 2086 saddr = xfrm_flowi_saddr(fl, family); 2087 if (unlikely(!daddr || !saddr)) 2088 return NULL; 2089 2090 rcu_read_lock(); 2091 retry: 2092 do { 2093 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 2094 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2095 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 2096 2097 ret = NULL; 2098 hlist_for_each_entry_rcu(pol, chain, bydst) { 2099 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2100 if (err) { 2101 if (err == -ESRCH) 2102 continue; 2103 else { 2104 ret = ERR_PTR(err); 2105 goto fail; 2106 } 2107 } else { 2108 ret = pol; 2109 break; 2110 } 2111 } 2112 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2113 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2114 daddr)) 2115 goto skip_inexact; 2116 2117 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2118 family, dir, if_id); 2119 if (pol) { 2120 ret = pol; 2121 if (IS_ERR(pol)) 2122 goto fail; 2123 } 2124 2125 skip_inexact: 2126 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 2127 goto retry; 2128 2129 if (ret && !xfrm_pol_hold_rcu(ret)) 2130 goto retry; 2131 fail: 2132 rcu_read_unlock(); 2133 2134 return ret; 2135 } 2136 2137 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2138 const struct flowi *fl, 2139 u16 family, u8 dir, u32 if_id) 2140 { 2141 #ifdef CONFIG_XFRM_SUB_POLICY 2142 struct xfrm_policy *pol; 2143 2144 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2145 dir, if_id); 2146 if (pol != NULL) 2147 return pol; 2148 #endif 2149 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2150 dir, if_id); 2151 } 2152 2153 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2154 const struct flowi *fl, 2155 u16 family, u32 if_id) 2156 { 2157 struct xfrm_policy *pol; 2158 2159 rcu_read_lock(); 2160 again: 2161 pol = rcu_dereference(sk->sk_policy[dir]); 2162 if (pol != NULL) { 2163 bool match; 2164 int err = 0; 2165 2166 if (pol->family != family) { 2167 pol = NULL; 2168 goto out; 2169 } 2170 2171 match = xfrm_selector_match(&pol->selector, fl, family); 2172 if (match) { 2173 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2174 pol->if_id != if_id) { 2175 pol = NULL; 2176 goto out; 2177 } 2178 err = security_xfrm_policy_lookup(pol->security, 2179 fl->flowi_secid, 2180 dir); 2181 if (!err) { 2182 if (!xfrm_pol_hold_rcu(pol)) 2183 goto again; 2184 } else if (err == -ESRCH) { 2185 pol = NULL; 2186 } else { 2187 pol = ERR_PTR(err); 2188 } 2189 } else 2190 pol = NULL; 2191 } 2192 out: 2193 rcu_read_unlock(); 2194 return pol; 2195 } 2196 2197 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2198 { 2199 struct net *net = xp_net(pol); 2200 2201 list_add(&pol->walk.all, &net->xfrm.policy_all); 2202 net->xfrm.policy_count[dir]++; 2203 xfrm_pol_hold(pol); 2204 } 2205 2206 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2207 int dir) 2208 { 2209 struct net *net = xp_net(pol); 2210 2211 if (list_empty(&pol->walk.all)) 2212 return NULL; 2213 2214 /* Socket policies are not hashed. */ 2215 if (!hlist_unhashed(&pol->bydst)) { 2216 hlist_del_rcu(&pol->bydst); 2217 hlist_del_init(&pol->bydst_inexact_list); 2218 hlist_del(&pol->byidx); 2219 } 2220 2221 list_del_init(&pol->walk.all); 2222 net->xfrm.policy_count[dir]--; 2223 2224 return pol; 2225 } 2226 2227 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2228 { 2229 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2230 } 2231 2232 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2233 { 2234 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2235 } 2236 2237 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2238 { 2239 struct net *net = xp_net(pol); 2240 2241 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2242 pol = __xfrm_policy_unlink(pol, dir); 2243 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2244 if (pol) { 2245 xfrm_policy_kill(pol); 2246 return 0; 2247 } 2248 return -ENOENT; 2249 } 2250 EXPORT_SYMBOL(xfrm_policy_delete); 2251 2252 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2253 { 2254 struct net *net = sock_net(sk); 2255 struct xfrm_policy *old_pol; 2256 2257 #ifdef CONFIG_XFRM_SUB_POLICY 2258 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2259 return -EINVAL; 2260 #endif 2261 2262 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2263 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2264 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2265 if (pol) { 2266 pol->curlft.add_time = ktime_get_real_seconds(); 2267 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2268 xfrm_sk_policy_link(pol, dir); 2269 } 2270 rcu_assign_pointer(sk->sk_policy[dir], pol); 2271 if (old_pol) { 2272 if (pol) 2273 xfrm_policy_requeue(old_pol, pol); 2274 2275 /* Unlinking succeeds always. This is the only function 2276 * allowed to delete or replace socket policy. 2277 */ 2278 xfrm_sk_policy_unlink(old_pol, dir); 2279 } 2280 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2281 2282 if (old_pol) { 2283 xfrm_policy_kill(old_pol); 2284 } 2285 return 0; 2286 } 2287 2288 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2289 { 2290 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2291 struct net *net = xp_net(old); 2292 2293 if (newp) { 2294 newp->selector = old->selector; 2295 if (security_xfrm_policy_clone(old->security, 2296 &newp->security)) { 2297 kfree(newp); 2298 return NULL; /* ENOMEM */ 2299 } 2300 newp->lft = old->lft; 2301 newp->curlft = old->curlft; 2302 newp->mark = old->mark; 2303 newp->if_id = old->if_id; 2304 newp->action = old->action; 2305 newp->flags = old->flags; 2306 newp->xfrm_nr = old->xfrm_nr; 2307 newp->index = old->index; 2308 newp->type = old->type; 2309 newp->family = old->family; 2310 memcpy(newp->xfrm_vec, old->xfrm_vec, 2311 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2312 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2313 xfrm_sk_policy_link(newp, dir); 2314 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2315 xfrm_pol_put(newp); 2316 } 2317 return newp; 2318 } 2319 2320 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2321 { 2322 const struct xfrm_policy *p; 2323 struct xfrm_policy *np; 2324 int i, ret = 0; 2325 2326 rcu_read_lock(); 2327 for (i = 0; i < 2; i++) { 2328 p = rcu_dereference(osk->sk_policy[i]); 2329 if (p) { 2330 np = clone_policy(p, i); 2331 if (unlikely(!np)) { 2332 ret = -ENOMEM; 2333 break; 2334 } 2335 rcu_assign_pointer(sk->sk_policy[i], np); 2336 } 2337 } 2338 rcu_read_unlock(); 2339 return ret; 2340 } 2341 2342 static int 2343 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2344 xfrm_address_t *remote, unsigned short family, u32 mark) 2345 { 2346 int err; 2347 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2348 2349 if (unlikely(afinfo == NULL)) 2350 return -EINVAL; 2351 err = afinfo->get_saddr(net, oif, local, remote, mark); 2352 rcu_read_unlock(); 2353 return err; 2354 } 2355 2356 /* Resolve list of templates for the flow, given policy. */ 2357 2358 static int 2359 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2360 struct xfrm_state **xfrm, unsigned short family) 2361 { 2362 struct net *net = xp_net(policy); 2363 int nx; 2364 int i, error; 2365 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2366 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2367 xfrm_address_t tmp; 2368 2369 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2370 struct xfrm_state *x; 2371 xfrm_address_t *remote = daddr; 2372 xfrm_address_t *local = saddr; 2373 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2374 2375 if (tmpl->mode == XFRM_MODE_TUNNEL || 2376 tmpl->mode == XFRM_MODE_BEET) { 2377 remote = &tmpl->id.daddr; 2378 local = &tmpl->saddr; 2379 if (xfrm_addr_any(local, tmpl->encap_family)) { 2380 error = xfrm_get_saddr(net, fl->flowi_oif, 2381 &tmp, remote, 2382 tmpl->encap_family, 0); 2383 if (error) 2384 goto fail; 2385 local = &tmp; 2386 } 2387 } 2388 2389 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2390 family, policy->if_id); 2391 2392 if (x && x->km.state == XFRM_STATE_VALID) { 2393 xfrm[nx++] = x; 2394 daddr = remote; 2395 saddr = local; 2396 continue; 2397 } 2398 if (x) { 2399 error = (x->km.state == XFRM_STATE_ERROR ? 2400 -EINVAL : -EAGAIN); 2401 xfrm_state_put(x); 2402 } else if (error == -ESRCH) { 2403 error = -EAGAIN; 2404 } 2405 2406 if (!tmpl->optional) 2407 goto fail; 2408 } 2409 return nx; 2410 2411 fail: 2412 for (nx--; nx >= 0; nx--) 2413 xfrm_state_put(xfrm[nx]); 2414 return error; 2415 } 2416 2417 static int 2418 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2419 struct xfrm_state **xfrm, unsigned short family) 2420 { 2421 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2422 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2423 int cnx = 0; 2424 int error; 2425 int ret; 2426 int i; 2427 2428 for (i = 0; i < npols; i++) { 2429 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2430 error = -ENOBUFS; 2431 goto fail; 2432 } 2433 2434 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2435 if (ret < 0) { 2436 error = ret; 2437 goto fail; 2438 } else 2439 cnx += ret; 2440 } 2441 2442 /* found states are sorted for outbound processing */ 2443 if (npols > 1) 2444 xfrm_state_sort(xfrm, tpp, cnx, family); 2445 2446 return cnx; 2447 2448 fail: 2449 for (cnx--; cnx >= 0; cnx--) 2450 xfrm_state_put(tpp[cnx]); 2451 return error; 2452 2453 } 2454 2455 static int xfrm_get_tos(const struct flowi *fl, int family) 2456 { 2457 if (family == AF_INET) 2458 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2459 2460 return 0; 2461 } 2462 2463 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2464 { 2465 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2466 struct dst_ops *dst_ops; 2467 struct xfrm_dst *xdst; 2468 2469 if (!afinfo) 2470 return ERR_PTR(-EINVAL); 2471 2472 switch (family) { 2473 case AF_INET: 2474 dst_ops = &net->xfrm.xfrm4_dst_ops; 2475 break; 2476 #if IS_ENABLED(CONFIG_IPV6) 2477 case AF_INET6: 2478 dst_ops = &net->xfrm.xfrm6_dst_ops; 2479 break; 2480 #endif 2481 default: 2482 BUG(); 2483 } 2484 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2485 2486 if (likely(xdst)) { 2487 struct dst_entry *dst = &xdst->u.dst; 2488 2489 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 2490 } else 2491 xdst = ERR_PTR(-ENOBUFS); 2492 2493 rcu_read_unlock(); 2494 2495 return xdst; 2496 } 2497 2498 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2499 int nfheader_len) 2500 { 2501 if (dst->ops->family == AF_INET6) { 2502 struct rt6_info *rt = (struct rt6_info *)dst; 2503 path->path_cookie = rt6_get_cookie(rt); 2504 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2505 } 2506 } 2507 2508 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2509 const struct flowi *fl) 2510 { 2511 const struct xfrm_policy_afinfo *afinfo = 2512 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2513 int err; 2514 2515 if (!afinfo) 2516 return -EINVAL; 2517 2518 err = afinfo->fill_dst(xdst, dev, fl); 2519 2520 rcu_read_unlock(); 2521 2522 return err; 2523 } 2524 2525 2526 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2527 * all the metrics... Shortly, bundle a bundle. 2528 */ 2529 2530 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2531 struct xfrm_state **xfrm, 2532 struct xfrm_dst **bundle, 2533 int nx, 2534 const struct flowi *fl, 2535 struct dst_entry *dst) 2536 { 2537 const struct xfrm_state_afinfo *afinfo; 2538 const struct xfrm_mode *inner_mode; 2539 struct net *net = xp_net(policy); 2540 unsigned long now = jiffies; 2541 struct net_device *dev; 2542 struct xfrm_dst *xdst_prev = NULL; 2543 struct xfrm_dst *xdst0 = NULL; 2544 int i = 0; 2545 int err; 2546 int header_len = 0; 2547 int nfheader_len = 0; 2548 int trailer_len = 0; 2549 int tos; 2550 int family = policy->selector.family; 2551 xfrm_address_t saddr, daddr; 2552 2553 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2554 2555 tos = xfrm_get_tos(fl, family); 2556 2557 dst_hold(dst); 2558 2559 for (; i < nx; i++) { 2560 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2561 struct dst_entry *dst1 = &xdst->u.dst; 2562 2563 err = PTR_ERR(xdst); 2564 if (IS_ERR(xdst)) { 2565 dst_release(dst); 2566 goto put_states; 2567 } 2568 2569 bundle[i] = xdst; 2570 if (!xdst_prev) 2571 xdst0 = xdst; 2572 else 2573 /* Ref count is taken during xfrm_alloc_dst() 2574 * No need to do dst_clone() on dst1 2575 */ 2576 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2577 2578 if (xfrm[i]->sel.family == AF_UNSPEC) { 2579 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2580 xfrm_af2proto(family)); 2581 if (!inner_mode) { 2582 err = -EAFNOSUPPORT; 2583 dst_release(dst); 2584 goto put_states; 2585 } 2586 } else 2587 inner_mode = &xfrm[i]->inner_mode; 2588 2589 xdst->route = dst; 2590 dst_copy_metrics(dst1, dst); 2591 2592 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2593 __u32 mark = 0; 2594 2595 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2596 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2597 2598 family = xfrm[i]->props.family; 2599 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 2600 &saddr, &daddr, family, mark); 2601 err = PTR_ERR(dst); 2602 if (IS_ERR(dst)) 2603 goto put_states; 2604 } else 2605 dst_hold(dst); 2606 2607 dst1->xfrm = xfrm[i]; 2608 xdst->xfrm_genid = xfrm[i]->genid; 2609 2610 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2611 dst1->flags |= DST_HOST; 2612 dst1->lastuse = now; 2613 2614 dst1->input = dst_discard; 2615 2616 rcu_read_lock(); 2617 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2618 if (likely(afinfo)) 2619 dst1->output = afinfo->output; 2620 else 2621 dst1->output = dst_discard_out; 2622 rcu_read_unlock(); 2623 2624 xdst_prev = xdst; 2625 2626 header_len += xfrm[i]->props.header_len; 2627 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2628 nfheader_len += xfrm[i]->props.header_len; 2629 trailer_len += xfrm[i]->props.trailer_len; 2630 } 2631 2632 xfrm_dst_set_child(xdst_prev, dst); 2633 xdst0->path = dst; 2634 2635 err = -ENODEV; 2636 dev = dst->dev; 2637 if (!dev) 2638 goto free_dst; 2639 2640 xfrm_init_path(xdst0, dst, nfheader_len); 2641 xfrm_init_pmtu(bundle, nx); 2642 2643 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2644 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2645 err = xfrm_fill_dst(xdst_prev, dev, fl); 2646 if (err) 2647 goto free_dst; 2648 2649 xdst_prev->u.dst.header_len = header_len; 2650 xdst_prev->u.dst.trailer_len = trailer_len; 2651 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2652 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2653 } 2654 2655 return &xdst0->u.dst; 2656 2657 put_states: 2658 for (; i < nx; i++) 2659 xfrm_state_put(xfrm[i]); 2660 free_dst: 2661 if (xdst0) 2662 dst_release_immediate(&xdst0->u.dst); 2663 2664 return ERR_PTR(err); 2665 } 2666 2667 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2668 struct xfrm_policy **pols, 2669 int *num_pols, int *num_xfrms) 2670 { 2671 int i; 2672 2673 if (*num_pols == 0 || !pols[0]) { 2674 *num_pols = 0; 2675 *num_xfrms = 0; 2676 return 0; 2677 } 2678 if (IS_ERR(pols[0])) 2679 return PTR_ERR(pols[0]); 2680 2681 *num_xfrms = pols[0]->xfrm_nr; 2682 2683 #ifdef CONFIG_XFRM_SUB_POLICY 2684 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 2685 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2686 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2687 XFRM_POLICY_TYPE_MAIN, 2688 fl, family, 2689 XFRM_POLICY_OUT, 2690 pols[0]->if_id); 2691 if (pols[1]) { 2692 if (IS_ERR(pols[1])) { 2693 xfrm_pols_put(pols, *num_pols); 2694 return PTR_ERR(pols[1]); 2695 } 2696 (*num_pols)++; 2697 (*num_xfrms) += pols[1]->xfrm_nr; 2698 } 2699 } 2700 #endif 2701 for (i = 0; i < *num_pols; i++) { 2702 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2703 *num_xfrms = -1; 2704 break; 2705 } 2706 } 2707 2708 return 0; 2709 2710 } 2711 2712 static struct xfrm_dst * 2713 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2714 const struct flowi *fl, u16 family, 2715 struct dst_entry *dst_orig) 2716 { 2717 struct net *net = xp_net(pols[0]); 2718 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2719 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2720 struct xfrm_dst *xdst; 2721 struct dst_entry *dst; 2722 int err; 2723 2724 /* Try to instantiate a bundle */ 2725 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2726 if (err <= 0) { 2727 if (err == 0) 2728 return NULL; 2729 2730 if (err != -EAGAIN) 2731 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2732 return ERR_PTR(err); 2733 } 2734 2735 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2736 if (IS_ERR(dst)) { 2737 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2738 return ERR_CAST(dst); 2739 } 2740 2741 xdst = (struct xfrm_dst *)dst; 2742 xdst->num_xfrms = err; 2743 xdst->num_pols = num_pols; 2744 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2745 xdst->policy_genid = atomic_read(&pols[0]->genid); 2746 2747 return xdst; 2748 } 2749 2750 static void xfrm_policy_queue_process(struct timer_list *t) 2751 { 2752 struct sk_buff *skb; 2753 struct sock *sk; 2754 struct dst_entry *dst; 2755 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2756 struct net *net = xp_net(pol); 2757 struct xfrm_policy_queue *pq = &pol->polq; 2758 struct flowi fl; 2759 struct sk_buff_head list; 2760 2761 spin_lock(&pq->hold_queue.lock); 2762 skb = skb_peek(&pq->hold_queue); 2763 if (!skb) { 2764 spin_unlock(&pq->hold_queue.lock); 2765 goto out; 2766 } 2767 dst = skb_dst(skb); 2768 sk = skb->sk; 2769 xfrm_decode_session(skb, &fl, dst->ops->family); 2770 spin_unlock(&pq->hold_queue.lock); 2771 2772 dst_hold(xfrm_dst_path(dst)); 2773 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2774 if (IS_ERR(dst)) 2775 goto purge_queue; 2776 2777 if (dst->flags & DST_XFRM_QUEUE) { 2778 dst_release(dst); 2779 2780 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2781 goto purge_queue; 2782 2783 pq->timeout = pq->timeout << 1; 2784 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2785 xfrm_pol_hold(pol); 2786 goto out; 2787 } 2788 2789 dst_release(dst); 2790 2791 __skb_queue_head_init(&list); 2792 2793 spin_lock(&pq->hold_queue.lock); 2794 pq->timeout = 0; 2795 skb_queue_splice_init(&pq->hold_queue, &list); 2796 spin_unlock(&pq->hold_queue.lock); 2797 2798 while (!skb_queue_empty(&list)) { 2799 skb = __skb_dequeue(&list); 2800 2801 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2802 dst_hold(xfrm_dst_path(skb_dst(skb))); 2803 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2804 if (IS_ERR(dst)) { 2805 kfree_skb(skb); 2806 continue; 2807 } 2808 2809 nf_reset(skb); 2810 skb_dst_drop(skb); 2811 skb_dst_set(skb, dst); 2812 2813 dst_output(net, skb->sk, skb); 2814 } 2815 2816 out: 2817 xfrm_pol_put(pol); 2818 return; 2819 2820 purge_queue: 2821 pq->timeout = 0; 2822 skb_queue_purge(&pq->hold_queue); 2823 xfrm_pol_put(pol); 2824 } 2825 2826 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2827 { 2828 unsigned long sched_next; 2829 struct dst_entry *dst = skb_dst(skb); 2830 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2831 struct xfrm_policy *pol = xdst->pols[0]; 2832 struct xfrm_policy_queue *pq = &pol->polq; 2833 2834 if (unlikely(skb_fclone_busy(sk, skb))) { 2835 kfree_skb(skb); 2836 return 0; 2837 } 2838 2839 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2840 kfree_skb(skb); 2841 return -EAGAIN; 2842 } 2843 2844 skb_dst_force(skb); 2845 2846 spin_lock_bh(&pq->hold_queue.lock); 2847 2848 if (!pq->timeout) 2849 pq->timeout = XFRM_QUEUE_TMO_MIN; 2850 2851 sched_next = jiffies + pq->timeout; 2852 2853 if (del_timer(&pq->hold_timer)) { 2854 if (time_before(pq->hold_timer.expires, sched_next)) 2855 sched_next = pq->hold_timer.expires; 2856 xfrm_pol_put(pol); 2857 } 2858 2859 __skb_queue_tail(&pq->hold_queue, skb); 2860 if (!mod_timer(&pq->hold_timer, sched_next)) 2861 xfrm_pol_hold(pol); 2862 2863 spin_unlock_bh(&pq->hold_queue.lock); 2864 2865 return 0; 2866 } 2867 2868 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2869 struct xfrm_flo *xflo, 2870 const struct flowi *fl, 2871 int num_xfrms, 2872 u16 family) 2873 { 2874 int err; 2875 struct net_device *dev; 2876 struct dst_entry *dst; 2877 struct dst_entry *dst1; 2878 struct xfrm_dst *xdst; 2879 2880 xdst = xfrm_alloc_dst(net, family); 2881 if (IS_ERR(xdst)) 2882 return xdst; 2883 2884 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2885 net->xfrm.sysctl_larval_drop || 2886 num_xfrms <= 0) 2887 return xdst; 2888 2889 dst = xflo->dst_orig; 2890 dst1 = &xdst->u.dst; 2891 dst_hold(dst); 2892 xdst->route = dst; 2893 2894 dst_copy_metrics(dst1, dst); 2895 2896 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2897 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2898 dst1->lastuse = jiffies; 2899 2900 dst1->input = dst_discard; 2901 dst1->output = xdst_queue_output; 2902 2903 dst_hold(dst); 2904 xfrm_dst_set_child(xdst, dst); 2905 xdst->path = dst; 2906 2907 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2908 2909 err = -ENODEV; 2910 dev = dst->dev; 2911 if (!dev) 2912 goto free_dst; 2913 2914 err = xfrm_fill_dst(xdst, dev, fl); 2915 if (err) 2916 goto free_dst; 2917 2918 out: 2919 return xdst; 2920 2921 free_dst: 2922 dst_release(dst1); 2923 xdst = ERR_PTR(err); 2924 goto out; 2925 } 2926 2927 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2928 const struct flowi *fl, 2929 u16 family, u8 dir, 2930 struct xfrm_flo *xflo, u32 if_id) 2931 { 2932 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2933 int num_pols = 0, num_xfrms = 0, err; 2934 struct xfrm_dst *xdst; 2935 2936 /* Resolve policies to use if we couldn't get them from 2937 * previous cache entry */ 2938 num_pols = 1; 2939 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2940 err = xfrm_expand_policies(fl, family, pols, 2941 &num_pols, &num_xfrms); 2942 if (err < 0) 2943 goto inc_error; 2944 if (num_pols == 0) 2945 return NULL; 2946 if (num_xfrms <= 0) 2947 goto make_dummy_bundle; 2948 2949 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2950 xflo->dst_orig); 2951 if (IS_ERR(xdst)) { 2952 err = PTR_ERR(xdst); 2953 if (err == -EREMOTE) { 2954 xfrm_pols_put(pols, num_pols); 2955 return NULL; 2956 } 2957 2958 if (err != -EAGAIN) 2959 goto error; 2960 goto make_dummy_bundle; 2961 } else if (xdst == NULL) { 2962 num_xfrms = 0; 2963 goto make_dummy_bundle; 2964 } 2965 2966 return xdst; 2967 2968 make_dummy_bundle: 2969 /* We found policies, but there's no bundles to instantiate: 2970 * either because the policy blocks, has no transformations or 2971 * we could not build template (no xfrm_states).*/ 2972 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2973 if (IS_ERR(xdst)) { 2974 xfrm_pols_put(pols, num_pols); 2975 return ERR_CAST(xdst); 2976 } 2977 xdst->num_pols = num_pols; 2978 xdst->num_xfrms = num_xfrms; 2979 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2980 2981 return xdst; 2982 2983 inc_error: 2984 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2985 error: 2986 xfrm_pols_put(pols, num_pols); 2987 return ERR_PTR(err); 2988 } 2989 2990 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2991 struct dst_entry *dst_orig) 2992 { 2993 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2994 struct dst_entry *ret; 2995 2996 if (!afinfo) { 2997 dst_release(dst_orig); 2998 return ERR_PTR(-EINVAL); 2999 } else { 3000 ret = afinfo->blackhole_route(net, dst_orig); 3001 } 3002 rcu_read_unlock(); 3003 3004 return ret; 3005 } 3006 3007 /* Finds/creates a bundle for given flow and if_id 3008 * 3009 * At the moment we eat a raw IP route. Mostly to speed up lookups 3010 * on interfaces with disabled IPsec. 3011 * 3012 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3013 * compatibility 3014 */ 3015 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3016 struct dst_entry *dst_orig, 3017 const struct flowi *fl, 3018 const struct sock *sk, 3019 int flags, u32 if_id) 3020 { 3021 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3022 struct xfrm_dst *xdst; 3023 struct dst_entry *dst, *route; 3024 u16 family = dst_orig->ops->family; 3025 u8 dir = XFRM_POLICY_OUT; 3026 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3027 3028 dst = NULL; 3029 xdst = NULL; 3030 route = NULL; 3031 3032 sk = sk_const_to_full_sk(sk); 3033 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3034 num_pols = 1; 3035 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3036 if_id); 3037 err = xfrm_expand_policies(fl, family, pols, 3038 &num_pols, &num_xfrms); 3039 if (err < 0) 3040 goto dropdst; 3041 3042 if (num_pols) { 3043 if (num_xfrms <= 0) { 3044 drop_pols = num_pols; 3045 goto no_transform; 3046 } 3047 3048 xdst = xfrm_resolve_and_create_bundle( 3049 pols, num_pols, fl, 3050 family, dst_orig); 3051 3052 if (IS_ERR(xdst)) { 3053 xfrm_pols_put(pols, num_pols); 3054 err = PTR_ERR(xdst); 3055 if (err == -EREMOTE) 3056 goto nopol; 3057 3058 goto dropdst; 3059 } else if (xdst == NULL) { 3060 num_xfrms = 0; 3061 drop_pols = num_pols; 3062 goto no_transform; 3063 } 3064 3065 route = xdst->route; 3066 } 3067 } 3068 3069 if (xdst == NULL) { 3070 struct xfrm_flo xflo; 3071 3072 xflo.dst_orig = dst_orig; 3073 xflo.flags = flags; 3074 3075 /* To accelerate a bit... */ 3076 if ((dst_orig->flags & DST_NOXFRM) || 3077 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 3078 goto nopol; 3079 3080 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3081 if (xdst == NULL) 3082 goto nopol; 3083 if (IS_ERR(xdst)) { 3084 err = PTR_ERR(xdst); 3085 goto dropdst; 3086 } 3087 3088 num_pols = xdst->num_pols; 3089 num_xfrms = xdst->num_xfrms; 3090 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3091 route = xdst->route; 3092 } 3093 3094 dst = &xdst->u.dst; 3095 if (route == NULL && num_xfrms > 0) { 3096 /* The only case when xfrm_bundle_lookup() returns a 3097 * bundle with null route, is when the template could 3098 * not be resolved. It means policies are there, but 3099 * bundle could not be created, since we don't yet 3100 * have the xfrm_state's. We need to wait for KM to 3101 * negotiate new SA's or bail out with error.*/ 3102 if (net->xfrm.sysctl_larval_drop) { 3103 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3104 err = -EREMOTE; 3105 goto error; 3106 } 3107 3108 err = -EAGAIN; 3109 3110 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3111 goto error; 3112 } 3113 3114 no_transform: 3115 if (num_pols == 0) 3116 goto nopol; 3117 3118 if ((flags & XFRM_LOOKUP_ICMP) && 3119 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3120 err = -ENOENT; 3121 goto error; 3122 } 3123 3124 for (i = 0; i < num_pols; i++) 3125 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3126 3127 if (num_xfrms < 0) { 3128 /* Prohibit the flow */ 3129 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3130 err = -EPERM; 3131 goto error; 3132 } else if (num_xfrms > 0) { 3133 /* Flow transformed */ 3134 dst_release(dst_orig); 3135 } else { 3136 /* Flow passes untransformed */ 3137 dst_release(dst); 3138 dst = dst_orig; 3139 } 3140 ok: 3141 xfrm_pols_put(pols, drop_pols); 3142 if (dst && dst->xfrm && 3143 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3144 dst->flags |= DST_XFRM_TUNNEL; 3145 return dst; 3146 3147 nopol: 3148 if (!(flags & XFRM_LOOKUP_ICMP)) { 3149 dst = dst_orig; 3150 goto ok; 3151 } 3152 err = -ENOENT; 3153 error: 3154 dst_release(dst); 3155 dropdst: 3156 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3157 dst_release(dst_orig); 3158 xfrm_pols_put(pols, drop_pols); 3159 return ERR_PTR(err); 3160 } 3161 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3162 3163 /* Main function: finds/creates a bundle for given flow. 3164 * 3165 * At the moment we eat a raw IP route. Mostly to speed up lookups 3166 * on interfaces with disabled IPsec. 3167 */ 3168 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3169 const struct flowi *fl, const struct sock *sk, 3170 int flags) 3171 { 3172 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3173 } 3174 EXPORT_SYMBOL(xfrm_lookup); 3175 3176 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3177 * Otherwise we may send out blackholed packets. 3178 */ 3179 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3180 const struct flowi *fl, 3181 const struct sock *sk, int flags) 3182 { 3183 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3184 flags | XFRM_LOOKUP_QUEUE | 3185 XFRM_LOOKUP_KEEP_DST_REF); 3186 3187 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 3188 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3189 3190 if (IS_ERR(dst)) 3191 dst_release(dst_orig); 3192 3193 return dst; 3194 } 3195 EXPORT_SYMBOL(xfrm_lookup_route); 3196 3197 static inline int 3198 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3199 { 3200 struct sec_path *sp = skb_sec_path(skb); 3201 struct xfrm_state *x; 3202 3203 if (!sp || idx < 0 || idx >= sp->len) 3204 return 0; 3205 x = sp->xvec[idx]; 3206 if (!x->type->reject) 3207 return 0; 3208 return x->type->reject(x, skb, fl); 3209 } 3210 3211 /* When skb is transformed back to its "native" form, we have to 3212 * check policy restrictions. At the moment we make this in maximally 3213 * stupid way. Shame on me. :-) Of course, connected sockets must 3214 * have policy cached at them. 3215 */ 3216 3217 static inline int 3218 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3219 unsigned short family) 3220 { 3221 if (xfrm_state_kern(x)) 3222 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3223 return x->id.proto == tmpl->id.proto && 3224 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3225 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3226 x->props.mode == tmpl->mode && 3227 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3228 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3229 !(x->props.mode != XFRM_MODE_TRANSPORT && 3230 xfrm_state_addr_cmp(tmpl, x, family)); 3231 } 3232 3233 /* 3234 * 0 or more than 0 is returned when validation is succeeded (either bypass 3235 * because of optional transport mode, or next index of the mathced secpath 3236 * state with the template. 3237 * -1 is returned when no matching template is found. 3238 * Otherwise "-2 - errored_index" is returned. 3239 */ 3240 static inline int 3241 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3242 unsigned short family) 3243 { 3244 int idx = start; 3245 3246 if (tmpl->optional) { 3247 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3248 return start; 3249 } else 3250 start = -1; 3251 for (; idx < sp->len; idx++) { 3252 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3253 return ++idx; 3254 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3255 if (start == -1) 3256 start = -2-idx; 3257 break; 3258 } 3259 } 3260 return start; 3261 } 3262 3263 static void 3264 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3265 { 3266 const struct iphdr *iph = ip_hdr(skb); 3267 u8 *xprth = skb_network_header(skb) + iph->ihl * 4; 3268 struct flowi4 *fl4 = &fl->u.ip4; 3269 int oif = 0; 3270 3271 if (skb_dst(skb)) 3272 oif = skb_dst(skb)->dev->ifindex; 3273 3274 memset(fl4, 0, sizeof(struct flowi4)); 3275 fl4->flowi4_mark = skb->mark; 3276 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3277 3278 if (!ip_is_fragment(iph)) { 3279 switch (iph->protocol) { 3280 case IPPROTO_UDP: 3281 case IPPROTO_UDPLITE: 3282 case IPPROTO_TCP: 3283 case IPPROTO_SCTP: 3284 case IPPROTO_DCCP: 3285 if (xprth + 4 < skb->data || 3286 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3287 __be16 *ports; 3288 3289 xprth = skb_network_header(skb) + iph->ihl * 4; 3290 ports = (__be16 *)xprth; 3291 3292 fl4->fl4_sport = ports[!!reverse]; 3293 fl4->fl4_dport = ports[!reverse]; 3294 } 3295 break; 3296 case IPPROTO_ICMP: 3297 if (xprth + 2 < skb->data || 3298 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3299 u8 *icmp; 3300 3301 xprth = skb_network_header(skb) + iph->ihl * 4; 3302 icmp = xprth; 3303 3304 fl4->fl4_icmp_type = icmp[0]; 3305 fl4->fl4_icmp_code = icmp[1]; 3306 } 3307 break; 3308 case IPPROTO_ESP: 3309 if (xprth + 4 < skb->data || 3310 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3311 __be32 *ehdr; 3312 3313 xprth = skb_network_header(skb) + iph->ihl * 4; 3314 ehdr = (__be32 *)xprth; 3315 3316 fl4->fl4_ipsec_spi = ehdr[0]; 3317 } 3318 break; 3319 case IPPROTO_AH: 3320 if (xprth + 8 < skb->data || 3321 pskb_may_pull(skb, xprth + 8 - skb->data)) { 3322 __be32 *ah_hdr; 3323 3324 xprth = skb_network_header(skb) + iph->ihl * 4; 3325 ah_hdr = (__be32 *)xprth; 3326 3327 fl4->fl4_ipsec_spi = ah_hdr[1]; 3328 } 3329 break; 3330 case IPPROTO_COMP: 3331 if (xprth + 4 < skb->data || 3332 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3333 __be16 *ipcomp_hdr; 3334 3335 xprth = skb_network_header(skb) + iph->ihl * 4; 3336 ipcomp_hdr = (__be16 *)xprth; 3337 3338 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); 3339 } 3340 break; 3341 case IPPROTO_GRE: 3342 if (xprth + 12 < skb->data || 3343 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3344 __be16 *greflags; 3345 __be32 *gre_hdr; 3346 3347 xprth = skb_network_header(skb) + iph->ihl * 4; 3348 greflags = (__be16 *)xprth; 3349 gre_hdr = (__be32 *)xprth; 3350 3351 if (greflags[0] & GRE_KEY) { 3352 if (greflags[0] & GRE_CSUM) 3353 gre_hdr++; 3354 fl4->fl4_gre_key = gre_hdr[1]; 3355 } 3356 } 3357 break; 3358 default: 3359 fl4->fl4_ipsec_spi = 0; 3360 break; 3361 } 3362 } 3363 fl4->flowi4_proto = iph->protocol; 3364 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3365 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3366 fl4->flowi4_tos = iph->tos; 3367 } 3368 3369 #if IS_ENABLED(CONFIG_IPV6) 3370 static void 3371 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3372 { 3373 struct flowi6 *fl6 = &fl->u.ip6; 3374 int onlyproto = 0; 3375 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3376 u32 offset = sizeof(*hdr); 3377 struct ipv6_opt_hdr *exthdr; 3378 const unsigned char *nh = skb_network_header(skb); 3379 u16 nhoff = IP6CB(skb)->nhoff; 3380 int oif = 0; 3381 u8 nexthdr; 3382 3383 if (!nhoff) 3384 nhoff = offsetof(struct ipv6hdr, nexthdr); 3385 3386 nexthdr = nh[nhoff]; 3387 3388 if (skb_dst(skb)) 3389 oif = skb_dst(skb)->dev->ifindex; 3390 3391 memset(fl6, 0, sizeof(struct flowi6)); 3392 fl6->flowi6_mark = skb->mark; 3393 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3394 3395 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3396 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3397 3398 while (nh + offset + sizeof(*exthdr) < skb->data || 3399 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3400 nh = skb_network_header(skb); 3401 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3402 3403 switch (nexthdr) { 3404 case NEXTHDR_FRAGMENT: 3405 onlyproto = 1; 3406 /* fall through */ 3407 case NEXTHDR_ROUTING: 3408 case NEXTHDR_HOP: 3409 case NEXTHDR_DEST: 3410 offset += ipv6_optlen(exthdr); 3411 nexthdr = exthdr->nexthdr; 3412 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3413 break; 3414 case IPPROTO_UDP: 3415 case IPPROTO_UDPLITE: 3416 case IPPROTO_TCP: 3417 case IPPROTO_SCTP: 3418 case IPPROTO_DCCP: 3419 if (!onlyproto && (nh + offset + 4 < skb->data || 3420 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3421 __be16 *ports; 3422 3423 nh = skb_network_header(skb); 3424 ports = (__be16 *)(nh + offset); 3425 fl6->fl6_sport = ports[!!reverse]; 3426 fl6->fl6_dport = ports[!reverse]; 3427 } 3428 fl6->flowi6_proto = nexthdr; 3429 return; 3430 case IPPROTO_ICMPV6: 3431 if (!onlyproto && (nh + offset + 2 < skb->data || 3432 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3433 u8 *icmp; 3434 3435 nh = skb_network_header(skb); 3436 icmp = (u8 *)(nh + offset); 3437 fl6->fl6_icmp_type = icmp[0]; 3438 fl6->fl6_icmp_code = icmp[1]; 3439 } 3440 fl6->flowi6_proto = nexthdr; 3441 return; 3442 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3443 case IPPROTO_MH: 3444 offset += ipv6_optlen(exthdr); 3445 if (!onlyproto && (nh + offset + 3 < skb->data || 3446 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3447 struct ip6_mh *mh; 3448 3449 nh = skb_network_header(skb); 3450 mh = (struct ip6_mh *)(nh + offset); 3451 fl6->fl6_mh_type = mh->ip6mh_type; 3452 } 3453 fl6->flowi6_proto = nexthdr; 3454 return; 3455 #endif 3456 /* XXX Why are there these headers? */ 3457 case IPPROTO_AH: 3458 case IPPROTO_ESP: 3459 case IPPROTO_COMP: 3460 default: 3461 fl6->fl6_ipsec_spi = 0; 3462 fl6->flowi6_proto = nexthdr; 3463 return; 3464 } 3465 } 3466 } 3467 #endif 3468 3469 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3470 unsigned int family, int reverse) 3471 { 3472 switch (family) { 3473 case AF_INET: 3474 decode_session4(skb, fl, reverse); 3475 break; 3476 #if IS_ENABLED(CONFIG_IPV6) 3477 case AF_INET6: 3478 decode_session6(skb, fl, reverse); 3479 break; 3480 #endif 3481 default: 3482 return -EAFNOSUPPORT; 3483 } 3484 3485 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3486 } 3487 EXPORT_SYMBOL(__xfrm_decode_session); 3488 3489 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3490 { 3491 for (; k < sp->len; k++) { 3492 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3493 *idxp = k; 3494 return 1; 3495 } 3496 } 3497 3498 return 0; 3499 } 3500 3501 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3502 unsigned short family) 3503 { 3504 struct net *net = dev_net(skb->dev); 3505 struct xfrm_policy *pol; 3506 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3507 int npols = 0; 3508 int xfrm_nr; 3509 int pi; 3510 int reverse; 3511 struct flowi fl; 3512 int xerr_idx = -1; 3513 const struct xfrm_if_cb *ifcb; 3514 struct sec_path *sp; 3515 struct xfrm_if *xi; 3516 u32 if_id = 0; 3517 3518 rcu_read_lock(); 3519 ifcb = xfrm_if_get_cb(); 3520 3521 if (ifcb) { 3522 xi = ifcb->decode_session(skb, family); 3523 if (xi) { 3524 if_id = xi->p.if_id; 3525 net = xi->net; 3526 } 3527 } 3528 rcu_read_unlock(); 3529 3530 reverse = dir & ~XFRM_POLICY_MASK; 3531 dir &= XFRM_POLICY_MASK; 3532 3533 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3534 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3535 return 0; 3536 } 3537 3538 nf_nat_decode_session(skb, &fl, family); 3539 3540 /* First, check used SA against their selectors. */ 3541 sp = skb_sec_path(skb); 3542 if (sp) { 3543 int i; 3544 3545 for (i = sp->len - 1; i >= 0; i--) { 3546 struct xfrm_state *x = sp->xvec[i]; 3547 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3548 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3549 return 0; 3550 } 3551 } 3552 } 3553 3554 pol = NULL; 3555 sk = sk_to_full_sk(sk); 3556 if (sk && sk->sk_policy[dir]) { 3557 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3558 if (IS_ERR(pol)) { 3559 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3560 return 0; 3561 } 3562 } 3563 3564 if (!pol) 3565 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3566 3567 if (IS_ERR(pol)) { 3568 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3569 return 0; 3570 } 3571 3572 if (!pol) { 3573 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3574 xfrm_secpath_reject(xerr_idx, skb, &fl); 3575 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3576 return 0; 3577 } 3578 return 1; 3579 } 3580 3581 pol->curlft.use_time = ktime_get_real_seconds(); 3582 3583 pols[0] = pol; 3584 npols++; 3585 #ifdef CONFIG_XFRM_SUB_POLICY 3586 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3587 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3588 &fl, family, 3589 XFRM_POLICY_IN, if_id); 3590 if (pols[1]) { 3591 if (IS_ERR(pols[1])) { 3592 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3593 return 0; 3594 } 3595 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3596 npols++; 3597 } 3598 } 3599 #endif 3600 3601 if (pol->action == XFRM_POLICY_ALLOW) { 3602 static struct sec_path dummy; 3603 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3604 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3605 struct xfrm_tmpl **tpp = tp; 3606 int ti = 0; 3607 int i, k; 3608 3609 sp = skb_sec_path(skb); 3610 if (!sp) 3611 sp = &dummy; 3612 3613 for (pi = 0; pi < npols; pi++) { 3614 if (pols[pi] != pol && 3615 pols[pi]->action != XFRM_POLICY_ALLOW) { 3616 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3617 goto reject; 3618 } 3619 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3620 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3621 goto reject_error; 3622 } 3623 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3624 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3625 } 3626 xfrm_nr = ti; 3627 if (npols > 1) { 3628 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 3629 tpp = stp; 3630 } 3631 3632 /* For each tunnel xfrm, find the first matching tmpl. 3633 * For each tmpl before that, find corresponding xfrm. 3634 * Order is _important_. Later we will implement 3635 * some barriers, but at the moment barriers 3636 * are implied between each two transformations. 3637 */ 3638 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3639 k = xfrm_policy_ok(tpp[i], sp, k, family); 3640 if (k < 0) { 3641 if (k < -1) 3642 /* "-2 - errored_index" returned */ 3643 xerr_idx = -(2+k); 3644 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3645 goto reject; 3646 } 3647 } 3648 3649 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3650 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3651 goto reject; 3652 } 3653 3654 xfrm_pols_put(pols, npols); 3655 return 1; 3656 } 3657 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3658 3659 reject: 3660 xfrm_secpath_reject(xerr_idx, skb, &fl); 3661 reject_error: 3662 xfrm_pols_put(pols, npols); 3663 return 0; 3664 } 3665 EXPORT_SYMBOL(__xfrm_policy_check); 3666 3667 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3668 { 3669 struct net *net = dev_net(skb->dev); 3670 struct flowi fl; 3671 struct dst_entry *dst; 3672 int res = 1; 3673 3674 if (xfrm_decode_session(skb, &fl, family) < 0) { 3675 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3676 return 0; 3677 } 3678 3679 skb_dst_force(skb); 3680 if (!skb_dst(skb)) { 3681 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3682 return 0; 3683 } 3684 3685 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3686 if (IS_ERR(dst)) { 3687 res = 0; 3688 dst = NULL; 3689 } 3690 skb_dst_set(skb, dst); 3691 return res; 3692 } 3693 EXPORT_SYMBOL(__xfrm_route_forward); 3694 3695 /* Optimize later using cookies and generation ids. */ 3696 3697 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3698 { 3699 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3700 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3701 * get validated by dst_ops->check on every use. We do this 3702 * because when a normal route referenced by an XFRM dst is 3703 * obsoleted we do not go looking around for all parent 3704 * referencing XFRM dsts so that we can invalidate them. It 3705 * is just too much work. Instead we make the checks here on 3706 * every use. For example: 3707 * 3708 * XFRM dst A --> IPv4 dst X 3709 * 3710 * X is the "xdst->route" of A (X is also the "dst->path" of A 3711 * in this example). If X is marked obsolete, "A" will not 3712 * notice. That's what we are validating here via the 3713 * stale_bundle() check. 3714 * 3715 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3716 * be marked on it. 3717 * This will force stale_bundle() to fail on any xdst bundle with 3718 * this dst linked in it. 3719 */ 3720 if (dst->obsolete < 0 && !stale_bundle(dst)) 3721 return dst; 3722 3723 return NULL; 3724 } 3725 3726 static int stale_bundle(struct dst_entry *dst) 3727 { 3728 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3729 } 3730 3731 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3732 { 3733 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3734 dst->dev = dev_net(dev)->loopback_dev; 3735 dev_hold(dst->dev); 3736 dev_put(dev); 3737 } 3738 } 3739 EXPORT_SYMBOL(xfrm_dst_ifdown); 3740 3741 static void xfrm_link_failure(struct sk_buff *skb) 3742 { 3743 /* Impossible. Such dst must be popped before reaches point of failure. */ 3744 } 3745 3746 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3747 { 3748 if (dst) { 3749 if (dst->obsolete) { 3750 dst_release(dst); 3751 dst = NULL; 3752 } 3753 } 3754 return dst; 3755 } 3756 3757 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3758 { 3759 while (nr--) { 3760 struct xfrm_dst *xdst = bundle[nr]; 3761 u32 pmtu, route_mtu_cached; 3762 struct dst_entry *dst; 3763 3764 dst = &xdst->u.dst; 3765 pmtu = dst_mtu(xfrm_dst_child(dst)); 3766 xdst->child_mtu_cached = pmtu; 3767 3768 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3769 3770 route_mtu_cached = dst_mtu(xdst->route); 3771 xdst->route_mtu_cached = route_mtu_cached; 3772 3773 if (pmtu > route_mtu_cached) 3774 pmtu = route_mtu_cached; 3775 3776 dst_metric_set(dst, RTAX_MTU, pmtu); 3777 } 3778 } 3779 3780 /* Check that the bundle accepts the flow and its components are 3781 * still valid. 3782 */ 3783 3784 static int xfrm_bundle_ok(struct xfrm_dst *first) 3785 { 3786 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3787 struct dst_entry *dst = &first->u.dst; 3788 struct xfrm_dst *xdst; 3789 int start_from, nr; 3790 u32 mtu; 3791 3792 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3793 (dst->dev && !netif_running(dst->dev))) 3794 return 0; 3795 3796 if (dst->flags & DST_XFRM_QUEUE) 3797 return 1; 3798 3799 start_from = nr = 0; 3800 do { 3801 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3802 3803 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3804 return 0; 3805 if (xdst->xfrm_genid != dst->xfrm->genid) 3806 return 0; 3807 if (xdst->num_pols > 0 && 3808 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3809 return 0; 3810 3811 bundle[nr++] = xdst; 3812 3813 mtu = dst_mtu(xfrm_dst_child(dst)); 3814 if (xdst->child_mtu_cached != mtu) { 3815 start_from = nr; 3816 xdst->child_mtu_cached = mtu; 3817 } 3818 3819 if (!dst_check(xdst->route, xdst->route_cookie)) 3820 return 0; 3821 mtu = dst_mtu(xdst->route); 3822 if (xdst->route_mtu_cached != mtu) { 3823 start_from = nr; 3824 xdst->route_mtu_cached = mtu; 3825 } 3826 3827 dst = xfrm_dst_child(dst); 3828 } while (dst->xfrm); 3829 3830 if (likely(!start_from)) 3831 return 1; 3832 3833 xdst = bundle[start_from - 1]; 3834 mtu = xdst->child_mtu_cached; 3835 while (start_from--) { 3836 dst = &xdst->u.dst; 3837 3838 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3839 if (mtu > xdst->route_mtu_cached) 3840 mtu = xdst->route_mtu_cached; 3841 dst_metric_set(dst, RTAX_MTU, mtu); 3842 if (!start_from) 3843 break; 3844 3845 xdst = bundle[start_from - 1]; 3846 xdst->child_mtu_cached = mtu; 3847 } 3848 3849 return 1; 3850 } 3851 3852 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3853 { 3854 return dst_metric_advmss(xfrm_dst_path(dst)); 3855 } 3856 3857 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3858 { 3859 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3860 3861 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3862 } 3863 3864 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3865 const void *daddr) 3866 { 3867 while (dst->xfrm) { 3868 const struct xfrm_state *xfrm = dst->xfrm; 3869 3870 dst = xfrm_dst_child(dst); 3871 3872 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3873 continue; 3874 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3875 daddr = xfrm->coaddr; 3876 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3877 daddr = &xfrm->id.daddr; 3878 } 3879 return daddr; 3880 } 3881 3882 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3883 struct sk_buff *skb, 3884 const void *daddr) 3885 { 3886 const struct dst_entry *path = xfrm_dst_path(dst); 3887 3888 if (!skb) 3889 daddr = xfrm_get_dst_nexthop(dst, daddr); 3890 return path->ops->neigh_lookup(path, skb, daddr); 3891 } 3892 3893 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3894 { 3895 const struct dst_entry *path = xfrm_dst_path(dst); 3896 3897 daddr = xfrm_get_dst_nexthop(dst, daddr); 3898 path->ops->confirm_neigh(path, daddr); 3899 } 3900 3901 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3902 { 3903 int err = 0; 3904 3905 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3906 return -EAFNOSUPPORT; 3907 3908 spin_lock(&xfrm_policy_afinfo_lock); 3909 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3910 err = -EEXIST; 3911 else { 3912 struct dst_ops *dst_ops = afinfo->dst_ops; 3913 if (likely(dst_ops->kmem_cachep == NULL)) 3914 dst_ops->kmem_cachep = xfrm_dst_cache; 3915 if (likely(dst_ops->check == NULL)) 3916 dst_ops->check = xfrm_dst_check; 3917 if (likely(dst_ops->default_advmss == NULL)) 3918 dst_ops->default_advmss = xfrm_default_advmss; 3919 if (likely(dst_ops->mtu == NULL)) 3920 dst_ops->mtu = xfrm_mtu; 3921 if (likely(dst_ops->negative_advice == NULL)) 3922 dst_ops->negative_advice = xfrm_negative_advice; 3923 if (likely(dst_ops->link_failure == NULL)) 3924 dst_ops->link_failure = xfrm_link_failure; 3925 if (likely(dst_ops->neigh_lookup == NULL)) 3926 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3927 if (likely(!dst_ops->confirm_neigh)) 3928 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3929 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3930 } 3931 spin_unlock(&xfrm_policy_afinfo_lock); 3932 3933 return err; 3934 } 3935 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3936 3937 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3938 { 3939 struct dst_ops *dst_ops = afinfo->dst_ops; 3940 int i; 3941 3942 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3943 if (xfrm_policy_afinfo[i] != afinfo) 3944 continue; 3945 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3946 break; 3947 } 3948 3949 synchronize_rcu(); 3950 3951 dst_ops->kmem_cachep = NULL; 3952 dst_ops->check = NULL; 3953 dst_ops->negative_advice = NULL; 3954 dst_ops->link_failure = NULL; 3955 } 3956 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3957 3958 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3959 { 3960 spin_lock(&xfrm_if_cb_lock); 3961 rcu_assign_pointer(xfrm_if_cb, ifcb); 3962 spin_unlock(&xfrm_if_cb_lock); 3963 } 3964 EXPORT_SYMBOL(xfrm_if_register_cb); 3965 3966 void xfrm_if_unregister_cb(void) 3967 { 3968 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3969 synchronize_rcu(); 3970 } 3971 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3972 3973 #ifdef CONFIG_XFRM_STATISTICS 3974 static int __net_init xfrm_statistics_init(struct net *net) 3975 { 3976 int rv; 3977 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3978 if (!net->mib.xfrm_statistics) 3979 return -ENOMEM; 3980 rv = xfrm_proc_init(net); 3981 if (rv < 0) 3982 free_percpu(net->mib.xfrm_statistics); 3983 return rv; 3984 } 3985 3986 static void xfrm_statistics_fini(struct net *net) 3987 { 3988 xfrm_proc_fini(net); 3989 free_percpu(net->mib.xfrm_statistics); 3990 } 3991 #else 3992 static int __net_init xfrm_statistics_init(struct net *net) 3993 { 3994 return 0; 3995 } 3996 3997 static void xfrm_statistics_fini(struct net *net) 3998 { 3999 } 4000 #endif 4001 4002 static int __net_init xfrm_policy_init(struct net *net) 4003 { 4004 unsigned int hmask, sz; 4005 int dir, err; 4006 4007 if (net_eq(net, &init_net)) { 4008 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4009 sizeof(struct xfrm_dst), 4010 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4011 NULL); 4012 err = rhashtable_init(&xfrm_policy_inexact_table, 4013 &xfrm_pol_inexact_params); 4014 BUG_ON(err); 4015 } 4016 4017 hmask = 8 - 1; 4018 sz = (hmask+1) * sizeof(struct hlist_head); 4019 4020 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4021 if (!net->xfrm.policy_byidx) 4022 goto out_byidx; 4023 net->xfrm.policy_idx_hmask = hmask; 4024 4025 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4026 struct xfrm_policy_hash *htab; 4027 4028 net->xfrm.policy_count[dir] = 0; 4029 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4030 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4031 4032 htab = &net->xfrm.policy_bydst[dir]; 4033 htab->table = xfrm_hash_alloc(sz); 4034 if (!htab->table) 4035 goto out_bydst; 4036 htab->hmask = hmask; 4037 htab->dbits4 = 32; 4038 htab->sbits4 = 32; 4039 htab->dbits6 = 128; 4040 htab->sbits6 = 128; 4041 } 4042 net->xfrm.policy_hthresh.lbits4 = 32; 4043 net->xfrm.policy_hthresh.rbits4 = 32; 4044 net->xfrm.policy_hthresh.lbits6 = 128; 4045 net->xfrm.policy_hthresh.rbits6 = 128; 4046 4047 seqlock_init(&net->xfrm.policy_hthresh.lock); 4048 4049 INIT_LIST_HEAD(&net->xfrm.policy_all); 4050 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4051 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4052 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4053 return 0; 4054 4055 out_bydst: 4056 for (dir--; dir >= 0; dir--) { 4057 struct xfrm_policy_hash *htab; 4058 4059 htab = &net->xfrm.policy_bydst[dir]; 4060 xfrm_hash_free(htab->table, sz); 4061 } 4062 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4063 out_byidx: 4064 return -ENOMEM; 4065 } 4066 4067 static void xfrm_policy_fini(struct net *net) 4068 { 4069 struct xfrm_pol_inexact_bin *b, *t; 4070 unsigned int sz; 4071 int dir; 4072 4073 flush_work(&net->xfrm.policy_hash_work); 4074 #ifdef CONFIG_XFRM_SUB_POLICY 4075 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4076 #endif 4077 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4078 4079 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4080 4081 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4082 struct xfrm_policy_hash *htab; 4083 4084 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4085 4086 htab = &net->xfrm.policy_bydst[dir]; 4087 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4088 WARN_ON(!hlist_empty(htab->table)); 4089 xfrm_hash_free(htab->table, sz); 4090 } 4091 4092 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4093 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4094 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4095 4096 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4097 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4098 __xfrm_policy_inexact_prune_bin(b, true); 4099 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4100 } 4101 4102 static int __net_init xfrm_net_init(struct net *net) 4103 { 4104 int rv; 4105 4106 /* Initialize the per-net locks here */ 4107 spin_lock_init(&net->xfrm.xfrm_state_lock); 4108 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4109 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4110 4111 rv = xfrm_statistics_init(net); 4112 if (rv < 0) 4113 goto out_statistics; 4114 rv = xfrm_state_init(net); 4115 if (rv < 0) 4116 goto out_state; 4117 rv = xfrm_policy_init(net); 4118 if (rv < 0) 4119 goto out_policy; 4120 rv = xfrm_sysctl_init(net); 4121 if (rv < 0) 4122 goto out_sysctl; 4123 4124 return 0; 4125 4126 out_sysctl: 4127 xfrm_policy_fini(net); 4128 out_policy: 4129 xfrm_state_fini(net); 4130 out_state: 4131 xfrm_statistics_fini(net); 4132 out_statistics: 4133 return rv; 4134 } 4135 4136 static void __net_exit xfrm_net_exit(struct net *net) 4137 { 4138 xfrm_sysctl_fini(net); 4139 xfrm_policy_fini(net); 4140 xfrm_state_fini(net); 4141 xfrm_statistics_fini(net); 4142 } 4143 4144 static struct pernet_operations __net_initdata xfrm_net_ops = { 4145 .init = xfrm_net_init, 4146 .exit = xfrm_net_exit, 4147 }; 4148 4149 void __init xfrm_init(void) 4150 { 4151 register_pernet_subsys(&xfrm_net_ops); 4152 xfrm_dev_init(); 4153 seqcount_init(&xfrm_policy_hash_generation); 4154 xfrm_input_init(); 4155 4156 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4157 synchronize_rcu(); 4158 } 4159 4160 #ifdef CONFIG_AUDITSYSCALL 4161 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4162 struct audit_buffer *audit_buf) 4163 { 4164 struct xfrm_sec_ctx *ctx = xp->security; 4165 struct xfrm_selector *sel = &xp->selector; 4166 4167 if (ctx) 4168 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4169 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4170 4171 switch (sel->family) { 4172 case AF_INET: 4173 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4174 if (sel->prefixlen_s != 32) 4175 audit_log_format(audit_buf, " src_prefixlen=%d", 4176 sel->prefixlen_s); 4177 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4178 if (sel->prefixlen_d != 32) 4179 audit_log_format(audit_buf, " dst_prefixlen=%d", 4180 sel->prefixlen_d); 4181 break; 4182 case AF_INET6: 4183 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4184 if (sel->prefixlen_s != 128) 4185 audit_log_format(audit_buf, " src_prefixlen=%d", 4186 sel->prefixlen_s); 4187 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4188 if (sel->prefixlen_d != 128) 4189 audit_log_format(audit_buf, " dst_prefixlen=%d", 4190 sel->prefixlen_d); 4191 break; 4192 } 4193 } 4194 4195 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4196 { 4197 struct audit_buffer *audit_buf; 4198 4199 audit_buf = xfrm_audit_start("SPD-add"); 4200 if (audit_buf == NULL) 4201 return; 4202 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4203 audit_log_format(audit_buf, " res=%u", result); 4204 xfrm_audit_common_policyinfo(xp, audit_buf); 4205 audit_log_end(audit_buf); 4206 } 4207 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4208 4209 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4210 bool task_valid) 4211 { 4212 struct audit_buffer *audit_buf; 4213 4214 audit_buf = xfrm_audit_start("SPD-delete"); 4215 if (audit_buf == NULL) 4216 return; 4217 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4218 audit_log_format(audit_buf, " res=%u", result); 4219 xfrm_audit_common_policyinfo(xp, audit_buf); 4220 audit_log_end(audit_buf); 4221 } 4222 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4223 #endif 4224 4225 #ifdef CONFIG_XFRM_MIGRATE 4226 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4227 const struct xfrm_selector *sel_tgt) 4228 { 4229 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4230 if (sel_tgt->family == sel_cmp->family && 4231 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4232 sel_cmp->family) && 4233 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4234 sel_cmp->family) && 4235 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4236 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4237 return true; 4238 } 4239 } else { 4240 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4241 return true; 4242 } 4243 } 4244 return false; 4245 } 4246 4247 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4248 u8 dir, u8 type, struct net *net) 4249 { 4250 struct xfrm_policy *pol, *ret = NULL; 4251 struct hlist_head *chain; 4252 u32 priority = ~0U; 4253 4254 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4255 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4256 hlist_for_each_entry(pol, chain, bydst) { 4257 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4258 pol->type == type) { 4259 ret = pol; 4260 priority = ret->priority; 4261 break; 4262 } 4263 } 4264 chain = &net->xfrm.policy_inexact[dir]; 4265 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4266 if ((pol->priority >= priority) && ret) 4267 break; 4268 4269 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4270 pol->type == type) { 4271 ret = pol; 4272 break; 4273 } 4274 } 4275 4276 xfrm_pol_hold(ret); 4277 4278 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4279 4280 return ret; 4281 } 4282 4283 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4284 { 4285 int match = 0; 4286 4287 if (t->mode == m->mode && t->id.proto == m->proto && 4288 (m->reqid == 0 || t->reqid == m->reqid)) { 4289 switch (t->mode) { 4290 case XFRM_MODE_TUNNEL: 4291 case XFRM_MODE_BEET: 4292 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4293 m->old_family) && 4294 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4295 m->old_family)) { 4296 match = 1; 4297 } 4298 break; 4299 case XFRM_MODE_TRANSPORT: 4300 /* in case of transport mode, template does not store 4301 any IP addresses, hence we just compare mode and 4302 protocol */ 4303 match = 1; 4304 break; 4305 default: 4306 break; 4307 } 4308 } 4309 return match; 4310 } 4311 4312 /* update endpoint address(es) of template(s) */ 4313 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4314 struct xfrm_migrate *m, int num_migrate) 4315 { 4316 struct xfrm_migrate *mp; 4317 int i, j, n = 0; 4318 4319 write_lock_bh(&pol->lock); 4320 if (unlikely(pol->walk.dead)) { 4321 /* target policy has been deleted */ 4322 write_unlock_bh(&pol->lock); 4323 return -ENOENT; 4324 } 4325 4326 for (i = 0; i < pol->xfrm_nr; i++) { 4327 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4328 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4329 continue; 4330 n++; 4331 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4332 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4333 continue; 4334 /* update endpoints */ 4335 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4336 sizeof(pol->xfrm_vec[i].id.daddr)); 4337 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4338 sizeof(pol->xfrm_vec[i].saddr)); 4339 pol->xfrm_vec[i].encap_family = mp->new_family; 4340 /* flush bundles */ 4341 atomic_inc(&pol->genid); 4342 } 4343 } 4344 4345 write_unlock_bh(&pol->lock); 4346 4347 if (!n) 4348 return -ENODATA; 4349 4350 return 0; 4351 } 4352 4353 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4354 { 4355 int i, j; 4356 4357 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4358 return -EINVAL; 4359 4360 for (i = 0; i < num_migrate; i++) { 4361 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4362 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4363 return -EINVAL; 4364 4365 /* check if there is any duplicated entry */ 4366 for (j = i + 1; j < num_migrate; j++) { 4367 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4368 sizeof(m[i].old_daddr)) && 4369 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4370 sizeof(m[i].old_saddr)) && 4371 m[i].proto == m[j].proto && 4372 m[i].mode == m[j].mode && 4373 m[i].reqid == m[j].reqid && 4374 m[i].old_family == m[j].old_family) 4375 return -EINVAL; 4376 } 4377 } 4378 4379 return 0; 4380 } 4381 4382 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4383 struct xfrm_migrate *m, int num_migrate, 4384 struct xfrm_kmaddress *k, struct net *net, 4385 struct xfrm_encap_tmpl *encap) 4386 { 4387 int i, err, nx_cur = 0, nx_new = 0; 4388 struct xfrm_policy *pol = NULL; 4389 struct xfrm_state *x, *xc; 4390 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4391 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4392 struct xfrm_migrate *mp; 4393 4394 /* Stage 0 - sanity checks */ 4395 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4396 goto out; 4397 4398 if (dir >= XFRM_POLICY_MAX) { 4399 err = -EINVAL; 4400 goto out; 4401 } 4402 4403 /* Stage 1 - find policy */ 4404 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4405 err = -ENOENT; 4406 goto out; 4407 } 4408 4409 /* Stage 2 - find and update state(s) */ 4410 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4411 if ((x = xfrm_migrate_state_find(mp, net))) { 4412 x_cur[nx_cur] = x; 4413 nx_cur++; 4414 xc = xfrm_state_migrate(x, mp, encap); 4415 if (xc) { 4416 x_new[nx_new] = xc; 4417 nx_new++; 4418 } else { 4419 err = -ENODATA; 4420 goto restore_state; 4421 } 4422 } 4423 } 4424 4425 /* Stage 3 - update policy */ 4426 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4427 goto restore_state; 4428 4429 /* Stage 4 - delete old state(s) */ 4430 if (nx_cur) { 4431 xfrm_states_put(x_cur, nx_cur); 4432 xfrm_states_delete(x_cur, nx_cur); 4433 } 4434 4435 /* Stage 5 - announce */ 4436 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4437 4438 xfrm_pol_put(pol); 4439 4440 return 0; 4441 out: 4442 return err; 4443 4444 restore_state: 4445 if (pol) 4446 xfrm_pol_put(pol); 4447 if (nx_cur) 4448 xfrm_states_put(x_cur, nx_cur); 4449 if (nx_new) 4450 xfrm_states_delete(x_new, nx_new); 4451 4452 return err; 4453 } 4454 EXPORT_SYMBOL(xfrm_migrate); 4455 #endif 4456