1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * xfrm_policy.c 4 * 5 * Changes: 6 * Mitsuru KANDA @USAGI 7 * Kazunori MIYAZAWA @USAGI 8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 9 * IPv6 support 10 * Kazunori MIYAZAWA @USAGI 11 * YOSHIFUJI Hideaki 12 * Split up af-specific portion 13 * Derek Atkins <derek@ihtfp.com> Add the post_input processor 14 * 15 */ 16 17 #include <linux/err.h> 18 #include <linux/slab.h> 19 #include <linux/kmod.h> 20 #include <linux/list.h> 21 #include <linux/spinlock.h> 22 #include <linux/workqueue.h> 23 #include <linux/notifier.h> 24 #include <linux/netdevice.h> 25 #include <linux/netfilter.h> 26 #include <linux/module.h> 27 #include <linux/cache.h> 28 #include <linux/cpu.h> 29 #include <linux/audit.h> 30 #include <linux/rhashtable.h> 31 #include <linux/if_tunnel.h> 32 #include <net/dst.h> 33 #include <net/flow.h> 34 #include <net/inet_ecn.h> 35 #include <net/xfrm.h> 36 #include <net/ip.h> 37 #include <net/gre.h> 38 #if IS_ENABLED(CONFIG_IPV6_MIP6) 39 #include <net/mip6.h> 40 #endif 41 #ifdef CONFIG_XFRM_STATISTICS 42 #include <net/snmp.h> 43 #endif 44 #ifdef CONFIG_XFRM_ESPINTCP 45 #include <net/espintcp.h> 46 #endif 47 48 #include "xfrm_hash.h" 49 50 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 51 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 52 #define XFRM_MAX_QUEUE_LEN 100 53 54 struct xfrm_flo { 55 struct dst_entry *dst_orig; 56 u8 flags; 57 }; 58 59 /* prefixes smaller than this are stored in lists, not trees. */ 60 #define INEXACT_PREFIXLEN_IPV4 16 61 #define INEXACT_PREFIXLEN_IPV6 48 62 63 struct xfrm_pol_inexact_node { 64 struct rb_node node; 65 union { 66 xfrm_address_t addr; 67 struct rcu_head rcu; 68 }; 69 u8 prefixlen; 70 71 struct rb_root root; 72 73 /* the policies matching this node, can be empty list */ 74 struct hlist_head hhead; 75 }; 76 77 /* xfrm inexact policy search tree: 78 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id); 79 * | 80 * +---- root_d: sorted by daddr:prefix 81 * | | 82 * | xfrm_pol_inexact_node 83 * | | 84 * | +- root: sorted by saddr/prefix 85 * | | | 86 * | | xfrm_pol_inexact_node 87 * | | | 88 * | | + root: unused 89 * | | | 90 * | | + hhead: saddr:daddr policies 91 * | | 92 * | +- coarse policies and all any:daddr policies 93 * | 94 * +---- root_s: sorted by saddr:prefix 95 * | | 96 * | xfrm_pol_inexact_node 97 * | | 98 * | + root: unused 99 * | | 100 * | + hhead: saddr:any policies 101 * | 102 * +---- coarse policies and all any:any policies 103 * 104 * Lookups return four candidate lists: 105 * 1. any:any list from top-level xfrm_pol_inexact_bin 106 * 2. any:daddr list from daddr tree 107 * 3. saddr:daddr list from 2nd level daddr tree 108 * 4. saddr:any list from saddr tree 109 * 110 * This result set then needs to be searched for the policy with 111 * the lowest priority. If two results have same prio, youngest one wins. 112 */ 113 114 struct xfrm_pol_inexact_key { 115 possible_net_t net; 116 u32 if_id; 117 u16 family; 118 u8 dir, type; 119 }; 120 121 struct xfrm_pol_inexact_bin { 122 struct xfrm_pol_inexact_key k; 123 struct rhash_head head; 124 /* list containing '*:*' policies */ 125 struct hlist_head hhead; 126 127 seqcount_spinlock_t count; 128 /* tree sorted by daddr/prefix */ 129 struct rb_root root_d; 130 131 /* tree sorted by saddr/prefix */ 132 struct rb_root root_s; 133 134 /* slow path below */ 135 struct list_head inexact_bins; 136 struct rcu_head rcu; 137 }; 138 139 enum xfrm_pol_inexact_candidate_type { 140 XFRM_POL_CAND_BOTH, 141 XFRM_POL_CAND_SADDR, 142 XFRM_POL_CAND_DADDR, 143 XFRM_POL_CAND_ANY, 144 145 XFRM_POL_CAND_MAX, 146 }; 147 148 struct xfrm_pol_inexact_candidates { 149 struct hlist_head *res[XFRM_POL_CAND_MAX]; 150 }; 151 152 static DEFINE_SPINLOCK(xfrm_if_cb_lock); 153 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 154 155 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 156 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 157 __read_mostly; 158 159 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 160 161 static struct rhashtable xfrm_policy_inexact_table; 162 static const struct rhashtable_params xfrm_pol_inexact_params; 163 164 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 165 static int stale_bundle(struct dst_entry *dst); 166 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 167 static void xfrm_policy_queue_process(struct timer_list *t); 168 169 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 170 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 171 int dir); 172 173 static struct xfrm_pol_inexact_bin * 174 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, 175 u32 if_id); 176 177 static struct xfrm_pol_inexact_bin * 178 xfrm_policy_inexact_lookup_rcu(struct net *net, 179 u8 type, u16 family, u8 dir, u32 if_id); 180 static struct xfrm_policy * 181 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, 182 bool excl); 183 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 184 struct xfrm_policy *policy); 185 186 static bool 187 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 188 struct xfrm_pol_inexact_bin *b, 189 const xfrm_address_t *saddr, 190 const xfrm_address_t *daddr); 191 192 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 193 { 194 return refcount_inc_not_zero(&policy->refcnt); 195 } 196 197 static inline bool 198 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 199 { 200 const struct flowi4 *fl4 = &fl->u.ip4; 201 202 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 203 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 204 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 205 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 206 (fl4->flowi4_proto == sel->proto || !sel->proto) && 207 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 208 } 209 210 static inline bool 211 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 212 { 213 const struct flowi6 *fl6 = &fl->u.ip6; 214 215 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 216 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 217 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 218 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 219 (fl6->flowi6_proto == sel->proto || !sel->proto) && 220 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 221 } 222 223 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 224 unsigned short family) 225 { 226 switch (family) { 227 case AF_INET: 228 return __xfrm4_selector_match(sel, fl); 229 case AF_INET6: 230 return __xfrm6_selector_match(sel, fl); 231 } 232 return false; 233 } 234 235 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 236 { 237 const struct xfrm_policy_afinfo *afinfo; 238 239 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 240 return NULL; 241 rcu_read_lock(); 242 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 243 if (unlikely(!afinfo)) 244 rcu_read_unlock(); 245 return afinfo; 246 } 247 248 /* Called with rcu_read_lock(). */ 249 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 250 { 251 return rcu_dereference(xfrm_if_cb); 252 } 253 254 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 255 const xfrm_address_t *saddr, 256 const xfrm_address_t *daddr, 257 int family, u32 mark) 258 { 259 const struct xfrm_policy_afinfo *afinfo; 260 struct dst_entry *dst; 261 262 afinfo = xfrm_policy_get_afinfo(family); 263 if (unlikely(afinfo == NULL)) 264 return ERR_PTR(-EAFNOSUPPORT); 265 266 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 267 268 rcu_read_unlock(); 269 270 return dst; 271 } 272 EXPORT_SYMBOL(__xfrm_dst_lookup); 273 274 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 275 int tos, int oif, 276 xfrm_address_t *prev_saddr, 277 xfrm_address_t *prev_daddr, 278 int family, u32 mark) 279 { 280 struct net *net = xs_net(x); 281 xfrm_address_t *saddr = &x->props.saddr; 282 xfrm_address_t *daddr = &x->id.daddr; 283 struct dst_entry *dst; 284 285 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 286 saddr = x->coaddr; 287 daddr = prev_daddr; 288 } 289 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 290 saddr = prev_saddr; 291 daddr = x->coaddr; 292 } 293 294 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 295 296 if (!IS_ERR(dst)) { 297 if (prev_saddr != saddr) 298 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 299 if (prev_daddr != daddr) 300 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 301 } 302 303 return dst; 304 } 305 306 static inline unsigned long make_jiffies(long secs) 307 { 308 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 309 return MAX_SCHEDULE_TIMEOUT-1; 310 else 311 return secs*HZ; 312 } 313 314 static void xfrm_policy_timer(struct timer_list *t) 315 { 316 struct xfrm_policy *xp = from_timer(xp, t, timer); 317 time64_t now = ktime_get_real_seconds(); 318 time64_t next = TIME64_MAX; 319 int warn = 0; 320 int dir; 321 322 read_lock(&xp->lock); 323 324 if (unlikely(xp->walk.dead)) 325 goto out; 326 327 dir = xfrm_policy_id2dir(xp->index); 328 329 if (xp->lft.hard_add_expires_seconds) { 330 time64_t tmo = xp->lft.hard_add_expires_seconds + 331 xp->curlft.add_time - now; 332 if (tmo <= 0) 333 goto expired; 334 if (tmo < next) 335 next = tmo; 336 } 337 if (xp->lft.hard_use_expires_seconds) { 338 time64_t tmo = xp->lft.hard_use_expires_seconds + 339 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now; 340 if (tmo <= 0) 341 goto expired; 342 if (tmo < next) 343 next = tmo; 344 } 345 if (xp->lft.soft_add_expires_seconds) { 346 time64_t tmo = xp->lft.soft_add_expires_seconds + 347 xp->curlft.add_time - now; 348 if (tmo <= 0) { 349 warn = 1; 350 tmo = XFRM_KM_TIMEOUT; 351 } 352 if (tmo < next) 353 next = tmo; 354 } 355 if (xp->lft.soft_use_expires_seconds) { 356 time64_t tmo = xp->lft.soft_use_expires_seconds + 357 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now; 358 if (tmo <= 0) { 359 warn = 1; 360 tmo = XFRM_KM_TIMEOUT; 361 } 362 if (tmo < next) 363 next = tmo; 364 } 365 366 if (warn) 367 km_policy_expired(xp, dir, 0, 0); 368 if (next != TIME64_MAX && 369 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 370 xfrm_pol_hold(xp); 371 372 out: 373 read_unlock(&xp->lock); 374 xfrm_pol_put(xp); 375 return; 376 377 expired: 378 read_unlock(&xp->lock); 379 if (!xfrm_policy_delete(xp, dir)) 380 km_policy_expired(xp, dir, 1, 0); 381 xfrm_pol_put(xp); 382 } 383 384 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 385 * SPD calls. 386 */ 387 388 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 389 { 390 struct xfrm_policy *policy; 391 392 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 393 394 if (policy) { 395 write_pnet(&policy->xp_net, net); 396 INIT_LIST_HEAD(&policy->walk.all); 397 INIT_HLIST_NODE(&policy->bydst_inexact_list); 398 INIT_HLIST_NODE(&policy->bydst); 399 INIT_HLIST_NODE(&policy->byidx); 400 rwlock_init(&policy->lock); 401 refcount_set(&policy->refcnt, 1); 402 skb_queue_head_init(&policy->polq.hold_queue); 403 timer_setup(&policy->timer, xfrm_policy_timer, 0); 404 timer_setup(&policy->polq.hold_timer, 405 xfrm_policy_queue_process, 0); 406 } 407 return policy; 408 } 409 EXPORT_SYMBOL(xfrm_policy_alloc); 410 411 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 412 { 413 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 414 415 security_xfrm_policy_free(policy->security); 416 kfree(policy); 417 } 418 419 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 420 421 void xfrm_policy_destroy(struct xfrm_policy *policy) 422 { 423 BUG_ON(!policy->walk.dead); 424 425 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 426 BUG(); 427 428 xfrm_dev_policy_free(policy); 429 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 430 } 431 EXPORT_SYMBOL(xfrm_policy_destroy); 432 433 /* Rule must be locked. Release descendant resources, announce 434 * entry dead. The rule must be unlinked from lists to the moment. 435 */ 436 437 static void xfrm_policy_kill(struct xfrm_policy *policy) 438 { 439 write_lock_bh(&policy->lock); 440 policy->walk.dead = 1; 441 write_unlock_bh(&policy->lock); 442 443 atomic_inc(&policy->genid); 444 445 if (del_timer(&policy->polq.hold_timer)) 446 xfrm_pol_put(policy); 447 skb_queue_purge(&policy->polq.hold_queue); 448 449 if (del_timer(&policy->timer)) 450 xfrm_pol_put(policy); 451 452 xfrm_pol_put(policy); 453 } 454 455 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 456 457 static inline unsigned int idx_hash(struct net *net, u32 index) 458 { 459 return __idx_hash(index, net->xfrm.policy_idx_hmask); 460 } 461 462 /* calculate policy hash thresholds */ 463 static void __get_hash_thresh(struct net *net, 464 unsigned short family, int dir, 465 u8 *dbits, u8 *sbits) 466 { 467 switch (family) { 468 case AF_INET: 469 *dbits = net->xfrm.policy_bydst[dir].dbits4; 470 *sbits = net->xfrm.policy_bydst[dir].sbits4; 471 break; 472 473 case AF_INET6: 474 *dbits = net->xfrm.policy_bydst[dir].dbits6; 475 *sbits = net->xfrm.policy_bydst[dir].sbits6; 476 break; 477 478 default: 479 *dbits = 0; 480 *sbits = 0; 481 } 482 } 483 484 static struct hlist_head *policy_hash_bysel(struct net *net, 485 const struct xfrm_selector *sel, 486 unsigned short family, int dir) 487 { 488 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 489 unsigned int hash; 490 u8 dbits; 491 u8 sbits; 492 493 __get_hash_thresh(net, family, dir, &dbits, &sbits); 494 hash = __sel_hash(sel, family, hmask, dbits, sbits); 495 496 if (hash == hmask + 1) 497 return NULL; 498 499 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 500 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 501 } 502 503 static struct hlist_head *policy_hash_direct(struct net *net, 504 const xfrm_address_t *daddr, 505 const xfrm_address_t *saddr, 506 unsigned short family, int dir) 507 { 508 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 509 unsigned int hash; 510 u8 dbits; 511 u8 sbits; 512 513 __get_hash_thresh(net, family, dir, &dbits, &sbits); 514 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 515 516 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 517 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 518 } 519 520 static void xfrm_dst_hash_transfer(struct net *net, 521 struct hlist_head *list, 522 struct hlist_head *ndsttable, 523 unsigned int nhashmask, 524 int dir) 525 { 526 struct hlist_node *tmp, *entry0 = NULL; 527 struct xfrm_policy *pol; 528 unsigned int h0 = 0; 529 u8 dbits; 530 u8 sbits; 531 532 redo: 533 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 534 unsigned int h; 535 536 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 537 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 538 pol->family, nhashmask, dbits, sbits); 539 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) { 540 hlist_del_rcu(&pol->bydst); 541 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 542 h0 = h; 543 } else { 544 if (h != h0) 545 continue; 546 hlist_del_rcu(&pol->bydst); 547 hlist_add_behind_rcu(&pol->bydst, entry0); 548 } 549 entry0 = &pol->bydst; 550 } 551 if (!hlist_empty(list)) { 552 entry0 = NULL; 553 goto redo; 554 } 555 } 556 557 static void xfrm_idx_hash_transfer(struct hlist_head *list, 558 struct hlist_head *nidxtable, 559 unsigned int nhashmask) 560 { 561 struct hlist_node *tmp; 562 struct xfrm_policy *pol; 563 564 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 565 unsigned int h; 566 567 h = __idx_hash(pol->index, nhashmask); 568 hlist_add_head(&pol->byidx, nidxtable+h); 569 } 570 } 571 572 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 573 { 574 return ((old_hmask + 1) << 1) - 1; 575 } 576 577 static void xfrm_bydst_resize(struct net *net, int dir) 578 { 579 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 580 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 581 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 582 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 583 struct hlist_head *odst; 584 int i; 585 586 if (!ndst) 587 return; 588 589 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 590 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 591 592 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 593 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 594 595 for (i = hmask; i >= 0; i--) 596 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 597 598 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 599 net->xfrm.policy_bydst[dir].hmask = nhashmask; 600 601 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 602 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 603 604 synchronize_rcu(); 605 606 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 607 } 608 609 static void xfrm_byidx_resize(struct net *net) 610 { 611 unsigned int hmask = net->xfrm.policy_idx_hmask; 612 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 613 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 614 struct hlist_head *oidx = net->xfrm.policy_byidx; 615 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 616 int i; 617 618 if (!nidx) 619 return; 620 621 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 622 623 for (i = hmask; i >= 0; i--) 624 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 625 626 net->xfrm.policy_byidx = nidx; 627 net->xfrm.policy_idx_hmask = nhashmask; 628 629 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 630 631 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 632 } 633 634 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 635 { 636 unsigned int cnt = net->xfrm.policy_count[dir]; 637 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 638 639 if (total) 640 *total += cnt; 641 642 if ((hmask + 1) < xfrm_policy_hashmax && 643 cnt > hmask) 644 return 1; 645 646 return 0; 647 } 648 649 static inline int xfrm_byidx_should_resize(struct net *net, int total) 650 { 651 unsigned int hmask = net->xfrm.policy_idx_hmask; 652 653 if ((hmask + 1) < xfrm_policy_hashmax && 654 total > hmask) 655 return 1; 656 657 return 0; 658 } 659 660 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 661 { 662 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 663 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 664 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 665 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 666 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 667 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 668 si->spdhcnt = net->xfrm.policy_idx_hmask; 669 si->spdhmcnt = xfrm_policy_hashmax; 670 } 671 EXPORT_SYMBOL(xfrm_spd_getinfo); 672 673 static DEFINE_MUTEX(hash_resize_mutex); 674 static void xfrm_hash_resize(struct work_struct *work) 675 { 676 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 677 int dir, total; 678 679 mutex_lock(&hash_resize_mutex); 680 681 total = 0; 682 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 683 if (xfrm_bydst_should_resize(net, dir, &total)) 684 xfrm_bydst_resize(net, dir); 685 } 686 if (xfrm_byidx_should_resize(net, total)) 687 xfrm_byidx_resize(net); 688 689 mutex_unlock(&hash_resize_mutex); 690 } 691 692 /* Make sure *pol can be inserted into fastbin. 693 * Useful to check that later insert requests will be successful 694 * (provided xfrm_policy_lock is held throughout). 695 */ 696 static struct xfrm_pol_inexact_bin * 697 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) 698 { 699 struct xfrm_pol_inexact_bin *bin, *prev; 700 struct xfrm_pol_inexact_key k = { 701 .family = pol->family, 702 .type = pol->type, 703 .dir = dir, 704 .if_id = pol->if_id, 705 }; 706 struct net *net = xp_net(pol); 707 708 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 709 710 write_pnet(&k.net, net); 711 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, 712 xfrm_pol_inexact_params); 713 if (bin) 714 return bin; 715 716 bin = kzalloc(sizeof(*bin), GFP_ATOMIC); 717 if (!bin) 718 return NULL; 719 720 bin->k = k; 721 INIT_HLIST_HEAD(&bin->hhead); 722 bin->root_d = RB_ROOT; 723 bin->root_s = RB_ROOT; 724 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); 725 726 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, 727 &bin->k, &bin->head, 728 xfrm_pol_inexact_params); 729 if (!prev) { 730 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); 731 return bin; 732 } 733 734 kfree(bin); 735 736 return IS_ERR(prev) ? NULL : prev; 737 } 738 739 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, 740 int family, u8 prefixlen) 741 { 742 if (xfrm_addr_any(addr, family)) 743 return true; 744 745 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) 746 return true; 747 748 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) 749 return true; 750 751 return false; 752 } 753 754 static bool 755 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) 756 { 757 const xfrm_address_t *addr; 758 bool saddr_any, daddr_any; 759 u8 prefixlen; 760 761 addr = &policy->selector.saddr; 762 prefixlen = policy->selector.prefixlen_s; 763 764 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 765 policy->family, 766 prefixlen); 767 addr = &policy->selector.daddr; 768 prefixlen = policy->selector.prefixlen_d; 769 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 770 policy->family, 771 prefixlen); 772 return saddr_any && daddr_any; 773 } 774 775 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, 776 const xfrm_address_t *addr, u8 prefixlen) 777 { 778 node->addr = *addr; 779 node->prefixlen = prefixlen; 780 } 781 782 static struct xfrm_pol_inexact_node * 783 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) 784 { 785 struct xfrm_pol_inexact_node *node; 786 787 node = kzalloc(sizeof(*node), GFP_ATOMIC); 788 if (node) 789 xfrm_pol_inexact_node_init(node, addr, prefixlen); 790 791 return node; 792 } 793 794 static int xfrm_policy_addr_delta(const xfrm_address_t *a, 795 const xfrm_address_t *b, 796 u8 prefixlen, u16 family) 797 { 798 u32 ma, mb, mask; 799 unsigned int pdw, pbi; 800 int delta = 0; 801 802 switch (family) { 803 case AF_INET: 804 if (prefixlen == 0) 805 return 0; 806 mask = ~0U << (32 - prefixlen); 807 ma = ntohl(a->a4) & mask; 808 mb = ntohl(b->a4) & mask; 809 if (ma < mb) 810 delta = -1; 811 else if (ma > mb) 812 delta = 1; 813 break; 814 case AF_INET6: 815 pdw = prefixlen >> 5; 816 pbi = prefixlen & 0x1f; 817 818 if (pdw) { 819 delta = memcmp(a->a6, b->a6, pdw << 2); 820 if (delta) 821 return delta; 822 } 823 if (pbi) { 824 mask = ~0U << (32 - pbi); 825 ma = ntohl(a->a6[pdw]) & mask; 826 mb = ntohl(b->a6[pdw]) & mask; 827 if (ma < mb) 828 delta = -1; 829 else if (ma > mb) 830 delta = 1; 831 } 832 break; 833 default: 834 break; 835 } 836 837 return delta; 838 } 839 840 static void xfrm_policy_inexact_list_reinsert(struct net *net, 841 struct xfrm_pol_inexact_node *n, 842 u16 family) 843 { 844 unsigned int matched_s, matched_d; 845 struct xfrm_policy *policy, *p; 846 847 matched_s = 0; 848 matched_d = 0; 849 850 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 851 struct hlist_node *newpos = NULL; 852 bool matches_s, matches_d; 853 854 if (!policy->bydst_reinsert) 855 continue; 856 857 WARN_ON_ONCE(policy->family != family); 858 859 policy->bydst_reinsert = false; 860 hlist_for_each_entry(p, &n->hhead, bydst) { 861 if (policy->priority > p->priority) 862 newpos = &p->bydst; 863 else if (policy->priority == p->priority && 864 policy->pos > p->pos) 865 newpos = &p->bydst; 866 else 867 break; 868 } 869 870 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 871 hlist_add_behind_rcu(&policy->bydst, newpos); 872 else 873 hlist_add_head_rcu(&policy->bydst, &n->hhead); 874 875 /* paranoia checks follow. 876 * Check that the reinserted policy matches at least 877 * saddr or daddr for current node prefix. 878 * 879 * Matching both is fine, matching saddr in one policy 880 * (but not daddr) and then matching only daddr in another 881 * is a bug. 882 */ 883 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 884 &n->addr, 885 n->prefixlen, 886 family) == 0; 887 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 888 &n->addr, 889 n->prefixlen, 890 family) == 0; 891 if (matches_s && matches_d) 892 continue; 893 894 WARN_ON_ONCE(!matches_s && !matches_d); 895 if (matches_s) 896 matched_s++; 897 if (matches_d) 898 matched_d++; 899 WARN_ON_ONCE(matched_s && matched_d); 900 } 901 } 902 903 static void xfrm_policy_inexact_node_reinsert(struct net *net, 904 struct xfrm_pol_inexact_node *n, 905 struct rb_root *new, 906 u16 family) 907 { 908 struct xfrm_pol_inexact_node *node; 909 struct rb_node **p, *parent; 910 911 /* we should not have another subtree here */ 912 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 913 restart: 914 parent = NULL; 915 p = &new->rb_node; 916 while (*p) { 917 u8 prefixlen; 918 int delta; 919 920 parent = *p; 921 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 922 923 prefixlen = min(node->prefixlen, n->prefixlen); 924 925 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 926 prefixlen, family); 927 if (delta < 0) { 928 p = &parent->rb_left; 929 } else if (delta > 0) { 930 p = &parent->rb_right; 931 } else { 932 bool same_prefixlen = node->prefixlen == n->prefixlen; 933 struct xfrm_policy *tmp; 934 935 hlist_for_each_entry(tmp, &n->hhead, bydst) { 936 tmp->bydst_reinsert = true; 937 hlist_del_rcu(&tmp->bydst); 938 } 939 940 node->prefixlen = prefixlen; 941 942 xfrm_policy_inexact_list_reinsert(net, node, family); 943 944 if (same_prefixlen) { 945 kfree_rcu(n, rcu); 946 return; 947 } 948 949 rb_erase(*p, new); 950 kfree_rcu(n, rcu); 951 n = node; 952 goto restart; 953 } 954 } 955 956 rb_link_node_rcu(&n->node, parent, p); 957 rb_insert_color(&n->node, new); 958 } 959 960 /* merge nodes v and n */ 961 static void xfrm_policy_inexact_node_merge(struct net *net, 962 struct xfrm_pol_inexact_node *v, 963 struct xfrm_pol_inexact_node *n, 964 u16 family) 965 { 966 struct xfrm_pol_inexact_node *node; 967 struct xfrm_policy *tmp; 968 struct rb_node *rnode; 969 970 /* To-be-merged node v has a subtree. 971 * 972 * Dismantle it and insert its nodes to n->root. 973 */ 974 while ((rnode = rb_first(&v->root)) != NULL) { 975 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 976 rb_erase(&node->node, &v->root); 977 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 978 family); 979 } 980 981 hlist_for_each_entry(tmp, &v->hhead, bydst) { 982 tmp->bydst_reinsert = true; 983 hlist_del_rcu(&tmp->bydst); 984 } 985 986 xfrm_policy_inexact_list_reinsert(net, n, family); 987 } 988 989 static struct xfrm_pol_inexact_node * 990 xfrm_policy_inexact_insert_node(struct net *net, 991 struct rb_root *root, 992 xfrm_address_t *addr, 993 u16 family, u8 prefixlen, u8 dir) 994 { 995 struct xfrm_pol_inexact_node *cached = NULL; 996 struct rb_node **p, *parent = NULL; 997 struct xfrm_pol_inexact_node *node; 998 999 p = &root->rb_node; 1000 while (*p) { 1001 int delta; 1002 1003 parent = *p; 1004 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 1005 1006 delta = xfrm_policy_addr_delta(addr, &node->addr, 1007 node->prefixlen, 1008 family); 1009 if (delta == 0 && prefixlen >= node->prefixlen) { 1010 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 1011 return node; 1012 } 1013 1014 if (delta < 0) 1015 p = &parent->rb_left; 1016 else 1017 p = &parent->rb_right; 1018 1019 if (prefixlen < node->prefixlen) { 1020 delta = xfrm_policy_addr_delta(addr, &node->addr, 1021 prefixlen, 1022 family); 1023 if (delta) 1024 continue; 1025 1026 /* This node is a subnet of the new prefix. It needs 1027 * to be removed and re-inserted with the smaller 1028 * prefix and all nodes that are now also covered 1029 * by the reduced prefixlen. 1030 */ 1031 rb_erase(&node->node, root); 1032 1033 if (!cached) { 1034 xfrm_pol_inexact_node_init(node, addr, 1035 prefixlen); 1036 cached = node; 1037 } else { 1038 /* This node also falls within the new 1039 * prefixlen. Merge the to-be-reinserted 1040 * node and this one. 1041 */ 1042 xfrm_policy_inexact_node_merge(net, node, 1043 cached, family); 1044 kfree_rcu(node, rcu); 1045 } 1046 1047 /* restart */ 1048 p = &root->rb_node; 1049 parent = NULL; 1050 } 1051 } 1052 1053 node = cached; 1054 if (!node) { 1055 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1056 if (!node) 1057 return NULL; 1058 } 1059 1060 rb_link_node_rcu(&node->node, parent, p); 1061 rb_insert_color(&node->node, root); 1062 1063 return node; 1064 } 1065 1066 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1067 { 1068 struct xfrm_pol_inexact_node *node; 1069 struct rb_node *rn = rb_first(r); 1070 1071 while (rn) { 1072 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1073 1074 xfrm_policy_inexact_gc_tree(&node->root, rm); 1075 rn = rb_next(rn); 1076 1077 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1078 WARN_ON_ONCE(rm); 1079 continue; 1080 } 1081 1082 rb_erase(&node->node, r); 1083 kfree_rcu(node, rcu); 1084 } 1085 } 1086 1087 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1088 { 1089 write_seqcount_begin(&b->count); 1090 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1091 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1092 write_seqcount_end(&b->count); 1093 1094 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1095 !hlist_empty(&b->hhead)) { 1096 WARN_ON_ONCE(net_exit); 1097 return; 1098 } 1099 1100 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1101 xfrm_pol_inexact_params) == 0) { 1102 list_del(&b->inexact_bins); 1103 kfree_rcu(b, rcu); 1104 } 1105 } 1106 1107 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1108 { 1109 struct net *net = read_pnet(&b->k.net); 1110 1111 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1112 __xfrm_policy_inexact_prune_bin(b, false); 1113 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1114 } 1115 1116 static void __xfrm_policy_inexact_flush(struct net *net) 1117 { 1118 struct xfrm_pol_inexact_bin *bin, *t; 1119 1120 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1121 1122 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1123 __xfrm_policy_inexact_prune_bin(bin, false); 1124 } 1125 1126 static struct hlist_head * 1127 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1128 struct xfrm_policy *policy, u8 dir) 1129 { 1130 struct xfrm_pol_inexact_node *n; 1131 struct net *net; 1132 1133 net = xp_net(policy); 1134 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1135 1136 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1137 return &bin->hhead; 1138 1139 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1140 policy->family, 1141 policy->selector.prefixlen_d)) { 1142 write_seqcount_begin(&bin->count); 1143 n = xfrm_policy_inexact_insert_node(net, 1144 &bin->root_s, 1145 &policy->selector.saddr, 1146 policy->family, 1147 policy->selector.prefixlen_s, 1148 dir); 1149 write_seqcount_end(&bin->count); 1150 if (!n) 1151 return NULL; 1152 1153 return &n->hhead; 1154 } 1155 1156 /* daddr is fixed */ 1157 write_seqcount_begin(&bin->count); 1158 n = xfrm_policy_inexact_insert_node(net, 1159 &bin->root_d, 1160 &policy->selector.daddr, 1161 policy->family, 1162 policy->selector.prefixlen_d, dir); 1163 write_seqcount_end(&bin->count); 1164 if (!n) 1165 return NULL; 1166 1167 /* saddr is wildcard */ 1168 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1169 policy->family, 1170 policy->selector.prefixlen_s)) 1171 return &n->hhead; 1172 1173 write_seqcount_begin(&bin->count); 1174 n = xfrm_policy_inexact_insert_node(net, 1175 &n->root, 1176 &policy->selector.saddr, 1177 policy->family, 1178 policy->selector.prefixlen_s, dir); 1179 write_seqcount_end(&bin->count); 1180 if (!n) 1181 return NULL; 1182 1183 return &n->hhead; 1184 } 1185 1186 static struct xfrm_policy * 1187 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1188 { 1189 struct xfrm_pol_inexact_bin *bin; 1190 struct xfrm_policy *delpol; 1191 struct hlist_head *chain; 1192 struct net *net; 1193 1194 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1195 if (!bin) 1196 return ERR_PTR(-ENOMEM); 1197 1198 net = xp_net(policy); 1199 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1200 1201 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1202 if (!chain) { 1203 __xfrm_policy_inexact_prune_bin(bin, false); 1204 return ERR_PTR(-ENOMEM); 1205 } 1206 1207 delpol = xfrm_policy_insert_list(chain, policy, excl); 1208 if (delpol && excl) { 1209 __xfrm_policy_inexact_prune_bin(bin, false); 1210 return ERR_PTR(-EEXIST); 1211 } 1212 1213 chain = &net->xfrm.policy_inexact[dir]; 1214 xfrm_policy_insert_inexact_list(chain, policy); 1215 1216 if (delpol) 1217 __xfrm_policy_inexact_prune_bin(bin, false); 1218 1219 return delpol; 1220 } 1221 1222 static void xfrm_hash_rebuild(struct work_struct *work) 1223 { 1224 struct net *net = container_of(work, struct net, 1225 xfrm.policy_hthresh.work); 1226 unsigned int hmask; 1227 struct xfrm_policy *pol; 1228 struct xfrm_policy *policy; 1229 struct hlist_head *chain; 1230 struct hlist_head *odst; 1231 struct hlist_node *newpos; 1232 int i; 1233 int dir; 1234 unsigned seq; 1235 u8 lbits4, rbits4, lbits6, rbits6; 1236 1237 mutex_lock(&hash_resize_mutex); 1238 1239 /* read selector prefixlen thresholds */ 1240 do { 1241 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1242 1243 lbits4 = net->xfrm.policy_hthresh.lbits4; 1244 rbits4 = net->xfrm.policy_hthresh.rbits4; 1245 lbits6 = net->xfrm.policy_hthresh.lbits6; 1246 rbits6 = net->xfrm.policy_hthresh.rbits6; 1247 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1248 1249 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1250 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 1251 1252 /* make sure that we can insert the indirect policies again before 1253 * we start with destructive action. 1254 */ 1255 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1256 struct xfrm_pol_inexact_bin *bin; 1257 u8 dbits, sbits; 1258 1259 dir = xfrm_policy_id2dir(policy->index); 1260 if (policy->walk.dead || dir >= XFRM_POLICY_MAX) 1261 continue; 1262 1263 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1264 if (policy->family == AF_INET) { 1265 dbits = rbits4; 1266 sbits = lbits4; 1267 } else { 1268 dbits = rbits6; 1269 sbits = lbits6; 1270 } 1271 } else { 1272 if (policy->family == AF_INET) { 1273 dbits = lbits4; 1274 sbits = rbits4; 1275 } else { 1276 dbits = lbits6; 1277 sbits = rbits6; 1278 } 1279 } 1280 1281 if (policy->selector.prefixlen_d < dbits || 1282 policy->selector.prefixlen_s < sbits) 1283 continue; 1284 1285 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1286 if (!bin) 1287 goto out_unlock; 1288 1289 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1290 goto out_unlock; 1291 } 1292 1293 /* reset the bydst and inexact table in all directions */ 1294 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1295 struct hlist_node *n; 1296 1297 hlist_for_each_entry_safe(policy, n, 1298 &net->xfrm.policy_inexact[dir], 1299 bydst_inexact_list) { 1300 hlist_del_rcu(&policy->bydst); 1301 hlist_del_init(&policy->bydst_inexact_list); 1302 } 1303 1304 hmask = net->xfrm.policy_bydst[dir].hmask; 1305 odst = net->xfrm.policy_bydst[dir].table; 1306 for (i = hmask; i >= 0; i--) { 1307 hlist_for_each_entry_safe(policy, n, odst + i, bydst) 1308 hlist_del_rcu(&policy->bydst); 1309 } 1310 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1311 /* dir out => dst = remote, src = local */ 1312 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1313 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1314 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1315 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1316 } else { 1317 /* dir in/fwd => dst = local, src = remote */ 1318 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1319 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1320 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1321 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1322 } 1323 } 1324 1325 /* re-insert all policies by order of creation */ 1326 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1327 if (policy->walk.dead) 1328 continue; 1329 dir = xfrm_policy_id2dir(policy->index); 1330 if (dir >= XFRM_POLICY_MAX) { 1331 /* skip socket policies */ 1332 continue; 1333 } 1334 newpos = NULL; 1335 chain = policy_hash_bysel(net, &policy->selector, 1336 policy->family, dir); 1337 1338 if (!chain) { 1339 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1340 1341 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1342 continue; 1343 } 1344 1345 hlist_for_each_entry(pol, chain, bydst) { 1346 if (policy->priority >= pol->priority) 1347 newpos = &pol->bydst; 1348 else 1349 break; 1350 } 1351 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1352 hlist_add_behind_rcu(&policy->bydst, newpos); 1353 else 1354 hlist_add_head_rcu(&policy->bydst, chain); 1355 } 1356 1357 out_unlock: 1358 __xfrm_policy_inexact_flush(net); 1359 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 1360 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1361 1362 mutex_unlock(&hash_resize_mutex); 1363 } 1364 1365 void xfrm_policy_hash_rebuild(struct net *net) 1366 { 1367 schedule_work(&net->xfrm.policy_hthresh.work); 1368 } 1369 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1370 1371 /* Generate new index... KAME seems to generate them ordered by cost 1372 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1373 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1374 { 1375 static u32 idx_generator; 1376 1377 for (;;) { 1378 struct hlist_head *list; 1379 struct xfrm_policy *p; 1380 u32 idx; 1381 int found; 1382 1383 if (!index) { 1384 idx = (idx_generator | dir); 1385 idx_generator += 8; 1386 } else { 1387 idx = index; 1388 index = 0; 1389 } 1390 1391 if (idx == 0) 1392 idx = 8; 1393 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1394 found = 0; 1395 hlist_for_each_entry(p, list, byidx) { 1396 if (p->index == idx) { 1397 found = 1; 1398 break; 1399 } 1400 } 1401 if (!found) 1402 return idx; 1403 } 1404 } 1405 1406 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1407 { 1408 u32 *p1 = (u32 *) s1; 1409 u32 *p2 = (u32 *) s2; 1410 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1411 int i; 1412 1413 for (i = 0; i < len; i++) { 1414 if (p1[i] != p2[i]) 1415 return 1; 1416 } 1417 1418 return 0; 1419 } 1420 1421 static void xfrm_policy_requeue(struct xfrm_policy *old, 1422 struct xfrm_policy *new) 1423 { 1424 struct xfrm_policy_queue *pq = &old->polq; 1425 struct sk_buff_head list; 1426 1427 if (skb_queue_empty(&pq->hold_queue)) 1428 return; 1429 1430 __skb_queue_head_init(&list); 1431 1432 spin_lock_bh(&pq->hold_queue.lock); 1433 skb_queue_splice_init(&pq->hold_queue, &list); 1434 if (del_timer(&pq->hold_timer)) 1435 xfrm_pol_put(old); 1436 spin_unlock_bh(&pq->hold_queue.lock); 1437 1438 pq = &new->polq; 1439 1440 spin_lock_bh(&pq->hold_queue.lock); 1441 skb_queue_splice(&list, &pq->hold_queue); 1442 pq->timeout = XFRM_QUEUE_TMO_MIN; 1443 if (!mod_timer(&pq->hold_timer, jiffies)) 1444 xfrm_pol_hold(new); 1445 spin_unlock_bh(&pq->hold_queue.lock); 1446 } 1447 1448 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark, 1449 struct xfrm_policy *pol) 1450 { 1451 return mark->v == pol->mark.v && mark->m == pol->mark.m; 1452 } 1453 1454 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1455 { 1456 const struct xfrm_pol_inexact_key *k = data; 1457 u32 a = k->type << 24 | k->dir << 16 | k->family; 1458 1459 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1460 seed); 1461 } 1462 1463 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1464 { 1465 const struct xfrm_pol_inexact_bin *b = data; 1466 1467 return xfrm_pol_bin_key(&b->k, 0, seed); 1468 } 1469 1470 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1471 const void *ptr) 1472 { 1473 const struct xfrm_pol_inexact_key *key = arg->key; 1474 const struct xfrm_pol_inexact_bin *b = ptr; 1475 int ret; 1476 1477 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1478 return -1; 1479 1480 ret = b->k.dir ^ key->dir; 1481 if (ret) 1482 return ret; 1483 1484 ret = b->k.type ^ key->type; 1485 if (ret) 1486 return ret; 1487 1488 ret = b->k.family ^ key->family; 1489 if (ret) 1490 return ret; 1491 1492 return b->k.if_id ^ key->if_id; 1493 } 1494 1495 static const struct rhashtable_params xfrm_pol_inexact_params = { 1496 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1497 .hashfn = xfrm_pol_bin_key, 1498 .obj_hashfn = xfrm_pol_bin_obj, 1499 .obj_cmpfn = xfrm_pol_bin_cmp, 1500 .automatic_shrinking = true, 1501 }; 1502 1503 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1504 struct xfrm_policy *policy) 1505 { 1506 struct xfrm_policy *pol, *delpol = NULL; 1507 struct hlist_node *newpos = NULL; 1508 int i = 0; 1509 1510 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1511 if (pol->type == policy->type && 1512 pol->if_id == policy->if_id && 1513 !selector_cmp(&pol->selector, &policy->selector) && 1514 xfrm_policy_mark_match(&policy->mark, pol) && 1515 xfrm_sec_ctx_match(pol->security, policy->security) && 1516 !WARN_ON(delpol)) { 1517 delpol = pol; 1518 if (policy->priority > pol->priority) 1519 continue; 1520 } else if (policy->priority >= pol->priority) { 1521 newpos = &pol->bydst_inexact_list; 1522 continue; 1523 } 1524 if (delpol) 1525 break; 1526 } 1527 1528 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1529 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1530 else 1531 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1532 1533 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1534 pol->pos = i; 1535 i++; 1536 } 1537 } 1538 1539 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1540 struct xfrm_policy *policy, 1541 bool excl) 1542 { 1543 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1544 1545 hlist_for_each_entry(pol, chain, bydst) { 1546 if (pol->type == policy->type && 1547 pol->if_id == policy->if_id && 1548 !selector_cmp(&pol->selector, &policy->selector) && 1549 xfrm_policy_mark_match(&policy->mark, pol) && 1550 xfrm_sec_ctx_match(pol->security, policy->security) && 1551 !WARN_ON(delpol)) { 1552 if (excl) 1553 return ERR_PTR(-EEXIST); 1554 delpol = pol; 1555 if (policy->priority > pol->priority) 1556 continue; 1557 } else if (policy->priority >= pol->priority) { 1558 newpos = pol; 1559 continue; 1560 } 1561 if (delpol) 1562 break; 1563 } 1564 1565 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1566 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1567 else 1568 /* Packet offload policies enter to the head 1569 * to speed-up lookups. 1570 */ 1571 hlist_add_head_rcu(&policy->bydst, chain); 1572 1573 return delpol; 1574 } 1575 1576 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1577 { 1578 struct net *net = xp_net(policy); 1579 struct xfrm_policy *delpol; 1580 struct hlist_head *chain; 1581 1582 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1583 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1584 if (chain) 1585 delpol = xfrm_policy_insert_list(chain, policy, excl); 1586 else 1587 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1588 1589 if (IS_ERR(delpol)) { 1590 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1591 return PTR_ERR(delpol); 1592 } 1593 1594 __xfrm_policy_link(policy, dir); 1595 1596 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1597 if (policy->family == AF_INET) 1598 rt_genid_bump_ipv4(net); 1599 else 1600 rt_genid_bump_ipv6(net); 1601 1602 if (delpol) { 1603 xfrm_policy_requeue(delpol, policy); 1604 __xfrm_policy_unlink(delpol, dir); 1605 } 1606 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1607 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1608 policy->curlft.add_time = ktime_get_real_seconds(); 1609 policy->curlft.use_time = 0; 1610 if (!mod_timer(&policy->timer, jiffies + HZ)) 1611 xfrm_pol_hold(policy); 1612 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1613 1614 if (delpol) 1615 xfrm_policy_kill(delpol); 1616 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1617 schedule_work(&net->xfrm.policy_hash_work); 1618 1619 return 0; 1620 } 1621 EXPORT_SYMBOL(xfrm_policy_insert); 1622 1623 static struct xfrm_policy * 1624 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark, 1625 u32 if_id, u8 type, int dir, struct xfrm_selector *sel, 1626 struct xfrm_sec_ctx *ctx) 1627 { 1628 struct xfrm_policy *pol; 1629 1630 if (!chain) 1631 return NULL; 1632 1633 hlist_for_each_entry(pol, chain, bydst) { 1634 if (pol->type == type && 1635 pol->if_id == if_id && 1636 xfrm_policy_mark_match(mark, pol) && 1637 !selector_cmp(sel, &pol->selector) && 1638 xfrm_sec_ctx_match(ctx, pol->security)) 1639 return pol; 1640 } 1641 1642 return NULL; 1643 } 1644 1645 struct xfrm_policy * 1646 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1647 u8 type, int dir, struct xfrm_selector *sel, 1648 struct xfrm_sec_ctx *ctx, int delete, int *err) 1649 { 1650 struct xfrm_pol_inexact_bin *bin = NULL; 1651 struct xfrm_policy *pol, *ret = NULL; 1652 struct hlist_head *chain; 1653 1654 *err = 0; 1655 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1656 chain = policy_hash_bysel(net, sel, sel->family, dir); 1657 if (!chain) { 1658 struct xfrm_pol_inexact_candidates cand; 1659 int i; 1660 1661 bin = xfrm_policy_inexact_lookup(net, type, 1662 sel->family, dir, if_id); 1663 if (!bin) { 1664 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1665 return NULL; 1666 } 1667 1668 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1669 &sel->saddr, 1670 &sel->daddr)) { 1671 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1672 return NULL; 1673 } 1674 1675 pol = NULL; 1676 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1677 struct xfrm_policy *tmp; 1678 1679 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1680 if_id, type, dir, 1681 sel, ctx); 1682 if (!tmp) 1683 continue; 1684 1685 if (!pol || tmp->pos < pol->pos) 1686 pol = tmp; 1687 } 1688 } else { 1689 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1690 sel, ctx); 1691 } 1692 1693 if (pol) { 1694 xfrm_pol_hold(pol); 1695 if (delete) { 1696 *err = security_xfrm_policy_delete(pol->security); 1697 if (*err) { 1698 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1699 return pol; 1700 } 1701 __xfrm_policy_unlink(pol, dir); 1702 } 1703 ret = pol; 1704 } 1705 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1706 1707 if (ret && delete) 1708 xfrm_policy_kill(ret); 1709 if (bin && delete) 1710 xfrm_policy_inexact_prune_bin(bin); 1711 return ret; 1712 } 1713 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1714 1715 struct xfrm_policy * 1716 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1717 u8 type, int dir, u32 id, int delete, int *err) 1718 { 1719 struct xfrm_policy *pol, *ret; 1720 struct hlist_head *chain; 1721 1722 *err = -ENOENT; 1723 if (xfrm_policy_id2dir(id) != dir) 1724 return NULL; 1725 1726 *err = 0; 1727 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1728 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1729 ret = NULL; 1730 hlist_for_each_entry(pol, chain, byidx) { 1731 if (pol->type == type && pol->index == id && 1732 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) { 1733 xfrm_pol_hold(pol); 1734 if (delete) { 1735 *err = security_xfrm_policy_delete( 1736 pol->security); 1737 if (*err) { 1738 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1739 return pol; 1740 } 1741 __xfrm_policy_unlink(pol, dir); 1742 } 1743 ret = pol; 1744 break; 1745 } 1746 } 1747 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1748 1749 if (ret && delete) 1750 xfrm_policy_kill(ret); 1751 return ret; 1752 } 1753 EXPORT_SYMBOL(xfrm_policy_byid); 1754 1755 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1756 static inline int 1757 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1758 { 1759 struct xfrm_policy *pol; 1760 int err = 0; 1761 1762 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1763 if (pol->walk.dead || 1764 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1765 pol->type != type) 1766 continue; 1767 1768 err = security_xfrm_policy_delete(pol->security); 1769 if (err) { 1770 xfrm_audit_policy_delete(pol, 0, task_valid); 1771 return err; 1772 } 1773 } 1774 return err; 1775 } 1776 1777 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, 1778 struct net_device *dev, 1779 bool task_valid) 1780 { 1781 struct xfrm_policy *pol; 1782 int err = 0; 1783 1784 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1785 if (pol->walk.dead || 1786 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1787 pol->xdo.dev != dev) 1788 continue; 1789 1790 err = security_xfrm_policy_delete(pol->security); 1791 if (err) { 1792 xfrm_audit_policy_delete(pol, 0, task_valid); 1793 return err; 1794 } 1795 } 1796 return err; 1797 } 1798 #else 1799 static inline int 1800 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1801 { 1802 return 0; 1803 } 1804 1805 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, 1806 struct net_device *dev, 1807 bool task_valid) 1808 { 1809 return 0; 1810 } 1811 #endif 1812 1813 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1814 { 1815 int dir, err = 0, cnt = 0; 1816 struct xfrm_policy *pol; 1817 1818 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1819 1820 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1821 if (err) 1822 goto out; 1823 1824 again: 1825 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1826 dir = xfrm_policy_id2dir(pol->index); 1827 if (pol->walk.dead || 1828 dir >= XFRM_POLICY_MAX || 1829 pol->type != type) 1830 continue; 1831 1832 __xfrm_policy_unlink(pol, dir); 1833 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1834 cnt++; 1835 xfrm_audit_policy_delete(pol, 1, task_valid); 1836 xfrm_policy_kill(pol); 1837 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1838 goto again; 1839 } 1840 if (cnt) 1841 __xfrm_policy_inexact_flush(net); 1842 else 1843 err = -ESRCH; 1844 out: 1845 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1846 return err; 1847 } 1848 EXPORT_SYMBOL(xfrm_policy_flush); 1849 1850 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev, 1851 bool task_valid) 1852 { 1853 int dir, err = 0, cnt = 0; 1854 struct xfrm_policy *pol; 1855 1856 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1857 1858 err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid); 1859 if (err) 1860 goto out; 1861 1862 again: 1863 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1864 dir = xfrm_policy_id2dir(pol->index); 1865 if (pol->walk.dead || 1866 dir >= XFRM_POLICY_MAX || 1867 pol->xdo.dev != dev) 1868 continue; 1869 1870 __xfrm_policy_unlink(pol, dir); 1871 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1872 cnt++; 1873 xfrm_audit_policy_delete(pol, 1, task_valid); 1874 xfrm_policy_kill(pol); 1875 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1876 goto again; 1877 } 1878 if (cnt) 1879 __xfrm_policy_inexact_flush(net); 1880 else 1881 err = -ESRCH; 1882 out: 1883 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1884 return err; 1885 } 1886 EXPORT_SYMBOL(xfrm_dev_policy_flush); 1887 1888 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1889 int (*func)(struct xfrm_policy *, int, int, void*), 1890 void *data) 1891 { 1892 struct xfrm_policy *pol; 1893 struct xfrm_policy_walk_entry *x; 1894 int error = 0; 1895 1896 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1897 walk->type != XFRM_POLICY_TYPE_ANY) 1898 return -EINVAL; 1899 1900 if (list_empty(&walk->walk.all) && walk->seq != 0) 1901 return 0; 1902 1903 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1904 if (list_empty(&walk->walk.all)) 1905 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1906 else 1907 x = list_first_entry(&walk->walk.all, 1908 struct xfrm_policy_walk_entry, all); 1909 1910 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1911 if (x->dead) 1912 continue; 1913 pol = container_of(x, struct xfrm_policy, walk); 1914 if (walk->type != XFRM_POLICY_TYPE_ANY && 1915 walk->type != pol->type) 1916 continue; 1917 error = func(pol, xfrm_policy_id2dir(pol->index), 1918 walk->seq, data); 1919 if (error) { 1920 list_move_tail(&walk->walk.all, &x->all); 1921 goto out; 1922 } 1923 walk->seq++; 1924 } 1925 if (walk->seq == 0) { 1926 error = -ENOENT; 1927 goto out; 1928 } 1929 list_del_init(&walk->walk.all); 1930 out: 1931 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1932 return error; 1933 } 1934 EXPORT_SYMBOL(xfrm_policy_walk); 1935 1936 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1937 { 1938 INIT_LIST_HEAD(&walk->walk.all); 1939 walk->walk.dead = 1; 1940 walk->type = type; 1941 walk->seq = 0; 1942 } 1943 EXPORT_SYMBOL(xfrm_policy_walk_init); 1944 1945 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1946 { 1947 if (list_empty(&walk->walk.all)) 1948 return; 1949 1950 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1951 list_del(&walk->walk.all); 1952 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1953 } 1954 EXPORT_SYMBOL(xfrm_policy_walk_done); 1955 1956 /* 1957 * Find policy to apply to this flow. 1958 * 1959 * Returns 0 if policy found, else an -errno. 1960 */ 1961 static int xfrm_policy_match(const struct xfrm_policy *pol, 1962 const struct flowi *fl, 1963 u8 type, u16 family, u32 if_id) 1964 { 1965 const struct xfrm_selector *sel = &pol->selector; 1966 int ret = -ESRCH; 1967 bool match; 1968 1969 if (pol->family != family || 1970 pol->if_id != if_id || 1971 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1972 pol->type != type) 1973 return ret; 1974 1975 match = xfrm_selector_match(sel, fl, family); 1976 if (match) 1977 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid); 1978 return ret; 1979 } 1980 1981 static struct xfrm_pol_inexact_node * 1982 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1983 seqcount_spinlock_t *count, 1984 const xfrm_address_t *addr, u16 family) 1985 { 1986 const struct rb_node *parent; 1987 int seq; 1988 1989 again: 1990 seq = read_seqcount_begin(count); 1991 1992 parent = rcu_dereference_raw(r->rb_node); 1993 while (parent) { 1994 struct xfrm_pol_inexact_node *node; 1995 int delta; 1996 1997 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1998 1999 delta = xfrm_policy_addr_delta(addr, &node->addr, 2000 node->prefixlen, family); 2001 if (delta < 0) { 2002 parent = rcu_dereference_raw(parent->rb_left); 2003 continue; 2004 } else if (delta > 0) { 2005 parent = rcu_dereference_raw(parent->rb_right); 2006 continue; 2007 } 2008 2009 return node; 2010 } 2011 2012 if (read_seqcount_retry(count, seq)) 2013 goto again; 2014 2015 return NULL; 2016 } 2017 2018 static bool 2019 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 2020 struct xfrm_pol_inexact_bin *b, 2021 const xfrm_address_t *saddr, 2022 const xfrm_address_t *daddr) 2023 { 2024 struct xfrm_pol_inexact_node *n; 2025 u16 family; 2026 2027 if (!b) 2028 return false; 2029 2030 family = b->k.family; 2031 memset(cand, 0, sizeof(*cand)); 2032 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 2033 2034 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 2035 family); 2036 if (n) { 2037 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 2038 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 2039 family); 2040 if (n) 2041 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 2042 } 2043 2044 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 2045 family); 2046 if (n) 2047 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 2048 2049 return true; 2050 } 2051 2052 static struct xfrm_pol_inexact_bin * 2053 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 2054 u8 dir, u32 if_id) 2055 { 2056 struct xfrm_pol_inexact_key k = { 2057 .family = family, 2058 .type = type, 2059 .dir = dir, 2060 .if_id = if_id, 2061 }; 2062 2063 write_pnet(&k.net, net); 2064 2065 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 2066 xfrm_pol_inexact_params); 2067 } 2068 2069 static struct xfrm_pol_inexact_bin * 2070 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 2071 u8 dir, u32 if_id) 2072 { 2073 struct xfrm_pol_inexact_bin *bin; 2074 2075 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2076 2077 rcu_read_lock(); 2078 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2079 rcu_read_unlock(); 2080 2081 return bin; 2082 } 2083 2084 static struct xfrm_policy * 2085 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2086 struct xfrm_policy *prefer, 2087 const struct flowi *fl, 2088 u8 type, u16 family, u32 if_id) 2089 { 2090 u32 priority = prefer ? prefer->priority : ~0u; 2091 struct xfrm_policy *pol; 2092 2093 if (!chain) 2094 return NULL; 2095 2096 hlist_for_each_entry_rcu(pol, chain, bydst) { 2097 int err; 2098 2099 if (pol->priority > priority) 2100 break; 2101 2102 err = xfrm_policy_match(pol, fl, type, family, if_id); 2103 if (err) { 2104 if (err != -ESRCH) 2105 return ERR_PTR(err); 2106 2107 continue; 2108 } 2109 2110 if (prefer) { 2111 /* matches. Is it older than *prefer? */ 2112 if (pol->priority == priority && 2113 prefer->pos < pol->pos) 2114 return prefer; 2115 } 2116 2117 return pol; 2118 } 2119 2120 return NULL; 2121 } 2122 2123 static struct xfrm_policy * 2124 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2125 struct xfrm_policy *prefer, 2126 const struct flowi *fl, 2127 u8 type, u16 family, u32 if_id) 2128 { 2129 struct xfrm_policy *tmp; 2130 int i; 2131 2132 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2133 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2134 prefer, 2135 fl, type, family, if_id); 2136 if (!tmp) 2137 continue; 2138 2139 if (IS_ERR(tmp)) 2140 return tmp; 2141 prefer = tmp; 2142 } 2143 2144 return prefer; 2145 } 2146 2147 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2148 const struct flowi *fl, 2149 u16 family, u8 dir, 2150 u32 if_id) 2151 { 2152 struct xfrm_pol_inexact_candidates cand; 2153 const xfrm_address_t *daddr, *saddr; 2154 struct xfrm_pol_inexact_bin *bin; 2155 struct xfrm_policy *pol, *ret; 2156 struct hlist_head *chain; 2157 unsigned int sequence; 2158 int err; 2159 2160 daddr = xfrm_flowi_daddr(fl, family); 2161 saddr = xfrm_flowi_saddr(fl, family); 2162 if (unlikely(!daddr || !saddr)) 2163 return NULL; 2164 2165 rcu_read_lock(); 2166 retry: 2167 do { 2168 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 2169 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2170 } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)); 2171 2172 ret = NULL; 2173 hlist_for_each_entry_rcu(pol, chain, bydst) { 2174 err = xfrm_policy_match(pol, fl, type, family, if_id); 2175 if (err) { 2176 if (err == -ESRCH) 2177 continue; 2178 else { 2179 ret = ERR_PTR(err); 2180 goto fail; 2181 } 2182 } else { 2183 ret = pol; 2184 break; 2185 } 2186 } 2187 if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET) 2188 goto skip_inexact; 2189 2190 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2191 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2192 daddr)) 2193 goto skip_inexact; 2194 2195 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2196 family, if_id); 2197 if (pol) { 2198 ret = pol; 2199 if (IS_ERR(pol)) 2200 goto fail; 2201 } 2202 2203 skip_inexact: 2204 if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)) 2205 goto retry; 2206 2207 if (ret && !xfrm_pol_hold_rcu(ret)) 2208 goto retry; 2209 fail: 2210 rcu_read_unlock(); 2211 2212 return ret; 2213 } 2214 2215 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2216 const struct flowi *fl, 2217 u16 family, u8 dir, u32 if_id) 2218 { 2219 #ifdef CONFIG_XFRM_SUB_POLICY 2220 struct xfrm_policy *pol; 2221 2222 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2223 dir, if_id); 2224 if (pol != NULL) 2225 return pol; 2226 #endif 2227 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2228 dir, if_id); 2229 } 2230 2231 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2232 const struct flowi *fl, 2233 u16 family, u32 if_id) 2234 { 2235 struct xfrm_policy *pol; 2236 2237 rcu_read_lock(); 2238 again: 2239 pol = rcu_dereference(sk->sk_policy[dir]); 2240 if (pol != NULL) { 2241 bool match; 2242 int err = 0; 2243 2244 if (pol->family != family) { 2245 pol = NULL; 2246 goto out; 2247 } 2248 2249 match = xfrm_selector_match(&pol->selector, fl, family); 2250 if (match) { 2251 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2252 pol->if_id != if_id) { 2253 pol = NULL; 2254 goto out; 2255 } 2256 err = security_xfrm_policy_lookup(pol->security, 2257 fl->flowi_secid); 2258 if (!err) { 2259 if (!xfrm_pol_hold_rcu(pol)) 2260 goto again; 2261 } else if (err == -ESRCH) { 2262 pol = NULL; 2263 } else { 2264 pol = ERR_PTR(err); 2265 } 2266 } else 2267 pol = NULL; 2268 } 2269 out: 2270 rcu_read_unlock(); 2271 return pol; 2272 } 2273 2274 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2275 { 2276 struct net *net = xp_net(pol); 2277 2278 list_add(&pol->walk.all, &net->xfrm.policy_all); 2279 net->xfrm.policy_count[dir]++; 2280 xfrm_pol_hold(pol); 2281 } 2282 2283 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2284 int dir) 2285 { 2286 struct net *net = xp_net(pol); 2287 2288 if (list_empty(&pol->walk.all)) 2289 return NULL; 2290 2291 /* Socket policies are not hashed. */ 2292 if (!hlist_unhashed(&pol->bydst)) { 2293 hlist_del_rcu(&pol->bydst); 2294 hlist_del_init(&pol->bydst_inexact_list); 2295 hlist_del(&pol->byidx); 2296 } 2297 2298 list_del_init(&pol->walk.all); 2299 net->xfrm.policy_count[dir]--; 2300 2301 return pol; 2302 } 2303 2304 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2305 { 2306 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2307 } 2308 2309 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2310 { 2311 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2312 } 2313 2314 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2315 { 2316 struct net *net = xp_net(pol); 2317 2318 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2319 pol = __xfrm_policy_unlink(pol, dir); 2320 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2321 if (pol) { 2322 xfrm_dev_policy_delete(pol); 2323 xfrm_policy_kill(pol); 2324 return 0; 2325 } 2326 return -ENOENT; 2327 } 2328 EXPORT_SYMBOL(xfrm_policy_delete); 2329 2330 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2331 { 2332 struct net *net = sock_net(sk); 2333 struct xfrm_policy *old_pol; 2334 2335 #ifdef CONFIG_XFRM_SUB_POLICY 2336 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2337 return -EINVAL; 2338 #endif 2339 2340 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2341 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2342 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2343 if (pol) { 2344 pol->curlft.add_time = ktime_get_real_seconds(); 2345 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2346 xfrm_sk_policy_link(pol, dir); 2347 } 2348 rcu_assign_pointer(sk->sk_policy[dir], pol); 2349 if (old_pol) { 2350 if (pol) 2351 xfrm_policy_requeue(old_pol, pol); 2352 2353 /* Unlinking succeeds always. This is the only function 2354 * allowed to delete or replace socket policy. 2355 */ 2356 xfrm_sk_policy_unlink(old_pol, dir); 2357 } 2358 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2359 2360 if (old_pol) { 2361 xfrm_policy_kill(old_pol); 2362 } 2363 return 0; 2364 } 2365 2366 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2367 { 2368 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2369 struct net *net = xp_net(old); 2370 2371 if (newp) { 2372 newp->selector = old->selector; 2373 if (security_xfrm_policy_clone(old->security, 2374 &newp->security)) { 2375 kfree(newp); 2376 return NULL; /* ENOMEM */ 2377 } 2378 newp->lft = old->lft; 2379 newp->curlft = old->curlft; 2380 newp->mark = old->mark; 2381 newp->if_id = old->if_id; 2382 newp->action = old->action; 2383 newp->flags = old->flags; 2384 newp->xfrm_nr = old->xfrm_nr; 2385 newp->index = old->index; 2386 newp->type = old->type; 2387 newp->family = old->family; 2388 memcpy(newp->xfrm_vec, old->xfrm_vec, 2389 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2390 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2391 xfrm_sk_policy_link(newp, dir); 2392 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2393 xfrm_pol_put(newp); 2394 } 2395 return newp; 2396 } 2397 2398 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2399 { 2400 const struct xfrm_policy *p; 2401 struct xfrm_policy *np; 2402 int i, ret = 0; 2403 2404 rcu_read_lock(); 2405 for (i = 0; i < 2; i++) { 2406 p = rcu_dereference(osk->sk_policy[i]); 2407 if (p) { 2408 np = clone_policy(p, i); 2409 if (unlikely(!np)) { 2410 ret = -ENOMEM; 2411 break; 2412 } 2413 rcu_assign_pointer(sk->sk_policy[i], np); 2414 } 2415 } 2416 rcu_read_unlock(); 2417 return ret; 2418 } 2419 2420 static int 2421 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2422 xfrm_address_t *remote, unsigned short family, u32 mark) 2423 { 2424 int err; 2425 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2426 2427 if (unlikely(afinfo == NULL)) 2428 return -EINVAL; 2429 err = afinfo->get_saddr(net, oif, local, remote, mark); 2430 rcu_read_unlock(); 2431 return err; 2432 } 2433 2434 /* Resolve list of templates for the flow, given policy. */ 2435 2436 static int 2437 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2438 struct xfrm_state **xfrm, unsigned short family) 2439 { 2440 struct net *net = xp_net(policy); 2441 int nx; 2442 int i, error; 2443 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2444 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2445 xfrm_address_t tmp; 2446 2447 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2448 struct xfrm_state *x; 2449 xfrm_address_t *remote = daddr; 2450 xfrm_address_t *local = saddr; 2451 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2452 2453 if (tmpl->mode == XFRM_MODE_TUNNEL || 2454 tmpl->mode == XFRM_MODE_BEET) { 2455 remote = &tmpl->id.daddr; 2456 local = &tmpl->saddr; 2457 if (xfrm_addr_any(local, tmpl->encap_family)) { 2458 error = xfrm_get_saddr(net, fl->flowi_oif, 2459 &tmp, remote, 2460 tmpl->encap_family, 0); 2461 if (error) 2462 goto fail; 2463 local = &tmp; 2464 } 2465 } 2466 2467 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2468 family, policy->if_id); 2469 2470 if (x && x->km.state == XFRM_STATE_VALID) { 2471 xfrm[nx++] = x; 2472 daddr = remote; 2473 saddr = local; 2474 continue; 2475 } 2476 if (x) { 2477 error = (x->km.state == XFRM_STATE_ERROR ? 2478 -EINVAL : -EAGAIN); 2479 xfrm_state_put(x); 2480 } else if (error == -ESRCH) { 2481 error = -EAGAIN; 2482 } 2483 2484 if (!tmpl->optional) 2485 goto fail; 2486 } 2487 return nx; 2488 2489 fail: 2490 for (nx--; nx >= 0; nx--) 2491 xfrm_state_put(xfrm[nx]); 2492 return error; 2493 } 2494 2495 static int 2496 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2497 struct xfrm_state **xfrm, unsigned short family) 2498 { 2499 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2500 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2501 int cnx = 0; 2502 int error; 2503 int ret; 2504 int i; 2505 2506 for (i = 0; i < npols; i++) { 2507 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2508 error = -ENOBUFS; 2509 goto fail; 2510 } 2511 2512 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2513 if (ret < 0) { 2514 error = ret; 2515 goto fail; 2516 } else 2517 cnx += ret; 2518 } 2519 2520 /* found states are sorted for outbound processing */ 2521 if (npols > 1) 2522 xfrm_state_sort(xfrm, tpp, cnx, family); 2523 2524 return cnx; 2525 2526 fail: 2527 for (cnx--; cnx >= 0; cnx--) 2528 xfrm_state_put(tpp[cnx]); 2529 return error; 2530 2531 } 2532 2533 static int xfrm_get_tos(const struct flowi *fl, int family) 2534 { 2535 if (family == AF_INET) 2536 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2537 2538 return 0; 2539 } 2540 2541 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2542 { 2543 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2544 struct dst_ops *dst_ops; 2545 struct xfrm_dst *xdst; 2546 2547 if (!afinfo) 2548 return ERR_PTR(-EINVAL); 2549 2550 switch (family) { 2551 case AF_INET: 2552 dst_ops = &net->xfrm.xfrm4_dst_ops; 2553 break; 2554 #if IS_ENABLED(CONFIG_IPV6) 2555 case AF_INET6: 2556 dst_ops = &net->xfrm.xfrm6_dst_ops; 2557 break; 2558 #endif 2559 default: 2560 BUG(); 2561 } 2562 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2563 2564 if (likely(xdst)) { 2565 memset_after(xdst, 0, u.dst); 2566 } else 2567 xdst = ERR_PTR(-ENOBUFS); 2568 2569 rcu_read_unlock(); 2570 2571 return xdst; 2572 } 2573 2574 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2575 int nfheader_len) 2576 { 2577 if (dst->ops->family == AF_INET6) { 2578 struct rt6_info *rt = (struct rt6_info *)dst; 2579 path->path_cookie = rt6_get_cookie(rt); 2580 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2581 } 2582 } 2583 2584 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2585 const struct flowi *fl) 2586 { 2587 const struct xfrm_policy_afinfo *afinfo = 2588 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2589 int err; 2590 2591 if (!afinfo) 2592 return -EINVAL; 2593 2594 err = afinfo->fill_dst(xdst, dev, fl); 2595 2596 rcu_read_unlock(); 2597 2598 return err; 2599 } 2600 2601 2602 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2603 * all the metrics... Shortly, bundle a bundle. 2604 */ 2605 2606 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2607 struct xfrm_state **xfrm, 2608 struct xfrm_dst **bundle, 2609 int nx, 2610 const struct flowi *fl, 2611 struct dst_entry *dst) 2612 { 2613 const struct xfrm_state_afinfo *afinfo; 2614 const struct xfrm_mode *inner_mode; 2615 struct net *net = xp_net(policy); 2616 unsigned long now = jiffies; 2617 struct net_device *dev; 2618 struct xfrm_dst *xdst_prev = NULL; 2619 struct xfrm_dst *xdst0 = NULL; 2620 int i = 0; 2621 int err; 2622 int header_len = 0; 2623 int nfheader_len = 0; 2624 int trailer_len = 0; 2625 int tos; 2626 int family = policy->selector.family; 2627 xfrm_address_t saddr, daddr; 2628 2629 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2630 2631 tos = xfrm_get_tos(fl, family); 2632 2633 dst_hold(dst); 2634 2635 for (; i < nx; i++) { 2636 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2637 struct dst_entry *dst1 = &xdst->u.dst; 2638 2639 err = PTR_ERR(xdst); 2640 if (IS_ERR(xdst)) { 2641 dst_release(dst); 2642 goto put_states; 2643 } 2644 2645 bundle[i] = xdst; 2646 if (!xdst_prev) 2647 xdst0 = xdst; 2648 else 2649 /* Ref count is taken during xfrm_alloc_dst() 2650 * No need to do dst_clone() on dst1 2651 */ 2652 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2653 2654 if (xfrm[i]->sel.family == AF_UNSPEC) { 2655 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2656 xfrm_af2proto(family)); 2657 if (!inner_mode) { 2658 err = -EAFNOSUPPORT; 2659 dst_release(dst); 2660 goto put_states; 2661 } 2662 } else 2663 inner_mode = &xfrm[i]->inner_mode; 2664 2665 xdst->route = dst; 2666 dst_copy_metrics(dst1, dst); 2667 2668 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2669 __u32 mark = 0; 2670 int oif; 2671 2672 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2673 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2674 2675 family = xfrm[i]->props.family; 2676 oif = fl->flowi_oif ? : fl->flowi_l3mdev; 2677 dst = xfrm_dst_lookup(xfrm[i], tos, oif, 2678 &saddr, &daddr, family, mark); 2679 err = PTR_ERR(dst); 2680 if (IS_ERR(dst)) 2681 goto put_states; 2682 } else 2683 dst_hold(dst); 2684 2685 dst1->xfrm = xfrm[i]; 2686 xdst->xfrm_genid = xfrm[i]->genid; 2687 2688 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2689 dst1->lastuse = now; 2690 2691 dst1->input = dst_discard; 2692 2693 rcu_read_lock(); 2694 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2695 if (likely(afinfo)) 2696 dst1->output = afinfo->output; 2697 else 2698 dst1->output = dst_discard_out; 2699 rcu_read_unlock(); 2700 2701 xdst_prev = xdst; 2702 2703 header_len += xfrm[i]->props.header_len; 2704 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2705 nfheader_len += xfrm[i]->props.header_len; 2706 trailer_len += xfrm[i]->props.trailer_len; 2707 } 2708 2709 xfrm_dst_set_child(xdst_prev, dst); 2710 xdst0->path = dst; 2711 2712 err = -ENODEV; 2713 dev = dst->dev; 2714 if (!dev) 2715 goto free_dst; 2716 2717 xfrm_init_path(xdst0, dst, nfheader_len); 2718 xfrm_init_pmtu(bundle, nx); 2719 2720 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2721 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2722 err = xfrm_fill_dst(xdst_prev, dev, fl); 2723 if (err) 2724 goto free_dst; 2725 2726 xdst_prev->u.dst.header_len = header_len; 2727 xdst_prev->u.dst.trailer_len = trailer_len; 2728 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2729 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2730 } 2731 2732 return &xdst0->u.dst; 2733 2734 put_states: 2735 for (; i < nx; i++) 2736 xfrm_state_put(xfrm[i]); 2737 free_dst: 2738 if (xdst0) 2739 dst_release_immediate(&xdst0->u.dst); 2740 2741 return ERR_PTR(err); 2742 } 2743 2744 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2745 struct xfrm_policy **pols, 2746 int *num_pols, int *num_xfrms) 2747 { 2748 int i; 2749 2750 if (*num_pols == 0 || !pols[0]) { 2751 *num_pols = 0; 2752 *num_xfrms = 0; 2753 return 0; 2754 } 2755 if (IS_ERR(pols[0])) { 2756 *num_pols = 0; 2757 return PTR_ERR(pols[0]); 2758 } 2759 2760 *num_xfrms = pols[0]->xfrm_nr; 2761 2762 #ifdef CONFIG_XFRM_SUB_POLICY 2763 if (pols[0]->action == XFRM_POLICY_ALLOW && 2764 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2765 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2766 XFRM_POLICY_TYPE_MAIN, 2767 fl, family, 2768 XFRM_POLICY_OUT, 2769 pols[0]->if_id); 2770 if (pols[1]) { 2771 if (IS_ERR(pols[1])) { 2772 xfrm_pols_put(pols, *num_pols); 2773 *num_pols = 0; 2774 return PTR_ERR(pols[1]); 2775 } 2776 (*num_pols)++; 2777 (*num_xfrms) += pols[1]->xfrm_nr; 2778 } 2779 } 2780 #endif 2781 for (i = 0; i < *num_pols; i++) { 2782 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2783 *num_xfrms = -1; 2784 break; 2785 } 2786 } 2787 2788 return 0; 2789 2790 } 2791 2792 static struct xfrm_dst * 2793 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2794 const struct flowi *fl, u16 family, 2795 struct dst_entry *dst_orig) 2796 { 2797 struct net *net = xp_net(pols[0]); 2798 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2799 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2800 struct xfrm_dst *xdst; 2801 struct dst_entry *dst; 2802 int err; 2803 2804 /* Try to instantiate a bundle */ 2805 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2806 if (err <= 0) { 2807 if (err == 0) 2808 return NULL; 2809 2810 if (err != -EAGAIN) 2811 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2812 return ERR_PTR(err); 2813 } 2814 2815 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2816 if (IS_ERR(dst)) { 2817 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2818 return ERR_CAST(dst); 2819 } 2820 2821 xdst = (struct xfrm_dst *)dst; 2822 xdst->num_xfrms = err; 2823 xdst->num_pols = num_pols; 2824 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2825 xdst->policy_genid = atomic_read(&pols[0]->genid); 2826 2827 return xdst; 2828 } 2829 2830 static void xfrm_policy_queue_process(struct timer_list *t) 2831 { 2832 struct sk_buff *skb; 2833 struct sock *sk; 2834 struct dst_entry *dst; 2835 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2836 struct net *net = xp_net(pol); 2837 struct xfrm_policy_queue *pq = &pol->polq; 2838 struct flowi fl; 2839 struct sk_buff_head list; 2840 __u32 skb_mark; 2841 2842 spin_lock(&pq->hold_queue.lock); 2843 skb = skb_peek(&pq->hold_queue); 2844 if (!skb) { 2845 spin_unlock(&pq->hold_queue.lock); 2846 goto out; 2847 } 2848 dst = skb_dst(skb); 2849 sk = skb->sk; 2850 2851 /* Fixup the mark to support VTI. */ 2852 skb_mark = skb->mark; 2853 skb->mark = pol->mark.v; 2854 xfrm_decode_session(skb, &fl, dst->ops->family); 2855 skb->mark = skb_mark; 2856 spin_unlock(&pq->hold_queue.lock); 2857 2858 dst_hold(xfrm_dst_path(dst)); 2859 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2860 if (IS_ERR(dst)) 2861 goto purge_queue; 2862 2863 if (dst->flags & DST_XFRM_QUEUE) { 2864 dst_release(dst); 2865 2866 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2867 goto purge_queue; 2868 2869 pq->timeout = pq->timeout << 1; 2870 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2871 xfrm_pol_hold(pol); 2872 goto out; 2873 } 2874 2875 dst_release(dst); 2876 2877 __skb_queue_head_init(&list); 2878 2879 spin_lock(&pq->hold_queue.lock); 2880 pq->timeout = 0; 2881 skb_queue_splice_init(&pq->hold_queue, &list); 2882 spin_unlock(&pq->hold_queue.lock); 2883 2884 while (!skb_queue_empty(&list)) { 2885 skb = __skb_dequeue(&list); 2886 2887 /* Fixup the mark to support VTI. */ 2888 skb_mark = skb->mark; 2889 skb->mark = pol->mark.v; 2890 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2891 skb->mark = skb_mark; 2892 2893 dst_hold(xfrm_dst_path(skb_dst(skb))); 2894 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2895 if (IS_ERR(dst)) { 2896 kfree_skb(skb); 2897 continue; 2898 } 2899 2900 nf_reset_ct(skb); 2901 skb_dst_drop(skb); 2902 skb_dst_set(skb, dst); 2903 2904 dst_output(net, skb->sk, skb); 2905 } 2906 2907 out: 2908 xfrm_pol_put(pol); 2909 return; 2910 2911 purge_queue: 2912 pq->timeout = 0; 2913 skb_queue_purge(&pq->hold_queue); 2914 xfrm_pol_put(pol); 2915 } 2916 2917 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2918 { 2919 unsigned long sched_next; 2920 struct dst_entry *dst = skb_dst(skb); 2921 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2922 struct xfrm_policy *pol = xdst->pols[0]; 2923 struct xfrm_policy_queue *pq = &pol->polq; 2924 2925 if (unlikely(skb_fclone_busy(sk, skb))) { 2926 kfree_skb(skb); 2927 return 0; 2928 } 2929 2930 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2931 kfree_skb(skb); 2932 return -EAGAIN; 2933 } 2934 2935 skb_dst_force(skb); 2936 2937 spin_lock_bh(&pq->hold_queue.lock); 2938 2939 if (!pq->timeout) 2940 pq->timeout = XFRM_QUEUE_TMO_MIN; 2941 2942 sched_next = jiffies + pq->timeout; 2943 2944 if (del_timer(&pq->hold_timer)) { 2945 if (time_before(pq->hold_timer.expires, sched_next)) 2946 sched_next = pq->hold_timer.expires; 2947 xfrm_pol_put(pol); 2948 } 2949 2950 __skb_queue_tail(&pq->hold_queue, skb); 2951 if (!mod_timer(&pq->hold_timer, sched_next)) 2952 xfrm_pol_hold(pol); 2953 2954 spin_unlock_bh(&pq->hold_queue.lock); 2955 2956 return 0; 2957 } 2958 2959 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2960 struct xfrm_flo *xflo, 2961 const struct flowi *fl, 2962 int num_xfrms, 2963 u16 family) 2964 { 2965 int err; 2966 struct net_device *dev; 2967 struct dst_entry *dst; 2968 struct dst_entry *dst1; 2969 struct xfrm_dst *xdst; 2970 2971 xdst = xfrm_alloc_dst(net, family); 2972 if (IS_ERR(xdst)) 2973 return xdst; 2974 2975 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2976 net->xfrm.sysctl_larval_drop || 2977 num_xfrms <= 0) 2978 return xdst; 2979 2980 dst = xflo->dst_orig; 2981 dst1 = &xdst->u.dst; 2982 dst_hold(dst); 2983 xdst->route = dst; 2984 2985 dst_copy_metrics(dst1, dst); 2986 2987 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2988 dst1->flags |= DST_XFRM_QUEUE; 2989 dst1->lastuse = jiffies; 2990 2991 dst1->input = dst_discard; 2992 dst1->output = xdst_queue_output; 2993 2994 dst_hold(dst); 2995 xfrm_dst_set_child(xdst, dst); 2996 xdst->path = dst; 2997 2998 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2999 3000 err = -ENODEV; 3001 dev = dst->dev; 3002 if (!dev) 3003 goto free_dst; 3004 3005 err = xfrm_fill_dst(xdst, dev, fl); 3006 if (err) 3007 goto free_dst; 3008 3009 out: 3010 return xdst; 3011 3012 free_dst: 3013 dst_release(dst1); 3014 xdst = ERR_PTR(err); 3015 goto out; 3016 } 3017 3018 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 3019 const struct flowi *fl, 3020 u16 family, u8 dir, 3021 struct xfrm_flo *xflo, u32 if_id) 3022 { 3023 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3024 int num_pols = 0, num_xfrms = 0, err; 3025 struct xfrm_dst *xdst; 3026 3027 /* Resolve policies to use if we couldn't get them from 3028 * previous cache entry */ 3029 num_pols = 1; 3030 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 3031 err = xfrm_expand_policies(fl, family, pols, 3032 &num_pols, &num_xfrms); 3033 if (err < 0) 3034 goto inc_error; 3035 if (num_pols == 0) 3036 return NULL; 3037 if (num_xfrms <= 0) 3038 goto make_dummy_bundle; 3039 3040 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 3041 xflo->dst_orig); 3042 if (IS_ERR(xdst)) { 3043 err = PTR_ERR(xdst); 3044 if (err == -EREMOTE) { 3045 xfrm_pols_put(pols, num_pols); 3046 return NULL; 3047 } 3048 3049 if (err != -EAGAIN) 3050 goto error; 3051 goto make_dummy_bundle; 3052 } else if (xdst == NULL) { 3053 num_xfrms = 0; 3054 goto make_dummy_bundle; 3055 } 3056 3057 return xdst; 3058 3059 make_dummy_bundle: 3060 /* We found policies, but there's no bundles to instantiate: 3061 * either because the policy blocks, has no transformations or 3062 * we could not build template (no xfrm_states).*/ 3063 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 3064 if (IS_ERR(xdst)) { 3065 xfrm_pols_put(pols, num_pols); 3066 return ERR_CAST(xdst); 3067 } 3068 xdst->num_pols = num_pols; 3069 xdst->num_xfrms = num_xfrms; 3070 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 3071 3072 return xdst; 3073 3074 inc_error: 3075 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 3076 error: 3077 xfrm_pols_put(pols, num_pols); 3078 return ERR_PTR(err); 3079 } 3080 3081 static struct dst_entry *make_blackhole(struct net *net, u16 family, 3082 struct dst_entry *dst_orig) 3083 { 3084 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 3085 struct dst_entry *ret; 3086 3087 if (!afinfo) { 3088 dst_release(dst_orig); 3089 return ERR_PTR(-EINVAL); 3090 } else { 3091 ret = afinfo->blackhole_route(net, dst_orig); 3092 } 3093 rcu_read_unlock(); 3094 3095 return ret; 3096 } 3097 3098 /* Finds/creates a bundle for given flow and if_id 3099 * 3100 * At the moment we eat a raw IP route. Mostly to speed up lookups 3101 * on interfaces with disabled IPsec. 3102 * 3103 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3104 * compatibility 3105 */ 3106 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3107 struct dst_entry *dst_orig, 3108 const struct flowi *fl, 3109 const struct sock *sk, 3110 int flags, u32 if_id) 3111 { 3112 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3113 struct xfrm_dst *xdst; 3114 struct dst_entry *dst, *route; 3115 u16 family = dst_orig->ops->family; 3116 u8 dir = XFRM_POLICY_OUT; 3117 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3118 3119 dst = NULL; 3120 xdst = NULL; 3121 route = NULL; 3122 3123 sk = sk_const_to_full_sk(sk); 3124 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3125 num_pols = 1; 3126 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3127 if_id); 3128 err = xfrm_expand_policies(fl, family, pols, 3129 &num_pols, &num_xfrms); 3130 if (err < 0) 3131 goto dropdst; 3132 3133 if (num_pols) { 3134 if (num_xfrms <= 0) { 3135 drop_pols = num_pols; 3136 goto no_transform; 3137 } 3138 3139 xdst = xfrm_resolve_and_create_bundle( 3140 pols, num_pols, fl, 3141 family, dst_orig); 3142 3143 if (IS_ERR(xdst)) { 3144 xfrm_pols_put(pols, num_pols); 3145 err = PTR_ERR(xdst); 3146 if (err == -EREMOTE) 3147 goto nopol; 3148 3149 goto dropdst; 3150 } else if (xdst == NULL) { 3151 num_xfrms = 0; 3152 drop_pols = num_pols; 3153 goto no_transform; 3154 } 3155 3156 route = xdst->route; 3157 } 3158 } 3159 3160 if (xdst == NULL) { 3161 struct xfrm_flo xflo; 3162 3163 xflo.dst_orig = dst_orig; 3164 xflo.flags = flags; 3165 3166 /* To accelerate a bit... */ 3167 if (!if_id && ((dst_orig->flags & DST_NOXFRM) || 3168 !net->xfrm.policy_count[XFRM_POLICY_OUT])) 3169 goto nopol; 3170 3171 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3172 if (xdst == NULL) 3173 goto nopol; 3174 if (IS_ERR(xdst)) { 3175 err = PTR_ERR(xdst); 3176 goto dropdst; 3177 } 3178 3179 num_pols = xdst->num_pols; 3180 num_xfrms = xdst->num_xfrms; 3181 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3182 route = xdst->route; 3183 } 3184 3185 dst = &xdst->u.dst; 3186 if (route == NULL && num_xfrms > 0) { 3187 /* The only case when xfrm_bundle_lookup() returns a 3188 * bundle with null route, is when the template could 3189 * not be resolved. It means policies are there, but 3190 * bundle could not be created, since we don't yet 3191 * have the xfrm_state's. We need to wait for KM to 3192 * negotiate new SA's or bail out with error.*/ 3193 if (net->xfrm.sysctl_larval_drop) { 3194 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3195 err = -EREMOTE; 3196 goto error; 3197 } 3198 3199 err = -EAGAIN; 3200 3201 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3202 goto error; 3203 } 3204 3205 no_transform: 3206 if (num_pols == 0) 3207 goto nopol; 3208 3209 if ((flags & XFRM_LOOKUP_ICMP) && 3210 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3211 err = -ENOENT; 3212 goto error; 3213 } 3214 3215 for (i = 0; i < num_pols; i++) 3216 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3217 3218 if (num_xfrms < 0) { 3219 /* Prohibit the flow */ 3220 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3221 err = -EPERM; 3222 goto error; 3223 } else if (num_xfrms > 0) { 3224 /* Flow transformed */ 3225 dst_release(dst_orig); 3226 } else { 3227 /* Flow passes untransformed */ 3228 dst_release(dst); 3229 dst = dst_orig; 3230 } 3231 ok: 3232 xfrm_pols_put(pols, drop_pols); 3233 if (dst && dst->xfrm && 3234 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3235 dst->flags |= DST_XFRM_TUNNEL; 3236 return dst; 3237 3238 nopol: 3239 if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) && 3240 net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { 3241 err = -EPERM; 3242 goto error; 3243 } 3244 if (!(flags & XFRM_LOOKUP_ICMP)) { 3245 dst = dst_orig; 3246 goto ok; 3247 } 3248 err = -ENOENT; 3249 error: 3250 dst_release(dst); 3251 dropdst: 3252 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3253 dst_release(dst_orig); 3254 xfrm_pols_put(pols, drop_pols); 3255 return ERR_PTR(err); 3256 } 3257 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3258 3259 /* Main function: finds/creates a bundle for given flow. 3260 * 3261 * At the moment we eat a raw IP route. Mostly to speed up lookups 3262 * on interfaces with disabled IPsec. 3263 */ 3264 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3265 const struct flowi *fl, const struct sock *sk, 3266 int flags) 3267 { 3268 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3269 } 3270 EXPORT_SYMBOL(xfrm_lookup); 3271 3272 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3273 * Otherwise we may send out blackholed packets. 3274 */ 3275 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3276 const struct flowi *fl, 3277 const struct sock *sk, int flags) 3278 { 3279 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3280 flags | XFRM_LOOKUP_QUEUE | 3281 XFRM_LOOKUP_KEEP_DST_REF); 3282 3283 if (PTR_ERR(dst) == -EREMOTE) 3284 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3285 3286 if (IS_ERR(dst)) 3287 dst_release(dst_orig); 3288 3289 return dst; 3290 } 3291 EXPORT_SYMBOL(xfrm_lookup_route); 3292 3293 static inline int 3294 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3295 { 3296 struct sec_path *sp = skb_sec_path(skb); 3297 struct xfrm_state *x; 3298 3299 if (!sp || idx < 0 || idx >= sp->len) 3300 return 0; 3301 x = sp->xvec[idx]; 3302 if (!x->type->reject) 3303 return 0; 3304 return x->type->reject(x, skb, fl); 3305 } 3306 3307 /* When skb is transformed back to its "native" form, we have to 3308 * check policy restrictions. At the moment we make this in maximally 3309 * stupid way. Shame on me. :-) Of course, connected sockets must 3310 * have policy cached at them. 3311 */ 3312 3313 static inline int 3314 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3315 unsigned short family) 3316 { 3317 if (xfrm_state_kern(x)) 3318 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3319 return x->id.proto == tmpl->id.proto && 3320 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3321 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3322 x->props.mode == tmpl->mode && 3323 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3324 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3325 !(x->props.mode != XFRM_MODE_TRANSPORT && 3326 xfrm_state_addr_cmp(tmpl, x, family)); 3327 } 3328 3329 /* 3330 * 0 or more than 0 is returned when validation is succeeded (either bypass 3331 * because of optional transport mode, or next index of the matched secpath 3332 * state with the template. 3333 * -1 is returned when no matching template is found. 3334 * Otherwise "-2 - errored_index" is returned. 3335 */ 3336 static inline int 3337 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3338 unsigned short family) 3339 { 3340 int idx = start; 3341 3342 if (tmpl->optional) { 3343 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3344 return start; 3345 } else 3346 start = -1; 3347 for (; idx < sp->len; idx++) { 3348 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3349 return ++idx; 3350 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3351 if (start == -1) 3352 start = -2-idx; 3353 break; 3354 } 3355 } 3356 return start; 3357 } 3358 3359 static void 3360 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3361 { 3362 const struct iphdr *iph = ip_hdr(skb); 3363 int ihl = iph->ihl; 3364 u8 *xprth = skb_network_header(skb) + ihl * 4; 3365 struct flowi4 *fl4 = &fl->u.ip4; 3366 int oif = 0; 3367 3368 if (skb_dst(skb) && skb_dst(skb)->dev) 3369 oif = skb_dst(skb)->dev->ifindex; 3370 3371 memset(fl4, 0, sizeof(struct flowi4)); 3372 fl4->flowi4_mark = skb->mark; 3373 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3374 3375 fl4->flowi4_proto = iph->protocol; 3376 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3377 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3378 fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK; 3379 3380 if (!ip_is_fragment(iph)) { 3381 switch (iph->protocol) { 3382 case IPPROTO_UDP: 3383 case IPPROTO_UDPLITE: 3384 case IPPROTO_TCP: 3385 case IPPROTO_SCTP: 3386 case IPPROTO_DCCP: 3387 if (xprth + 4 < skb->data || 3388 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3389 __be16 *ports; 3390 3391 xprth = skb_network_header(skb) + ihl * 4; 3392 ports = (__be16 *)xprth; 3393 3394 fl4->fl4_sport = ports[!!reverse]; 3395 fl4->fl4_dport = ports[!reverse]; 3396 } 3397 break; 3398 case IPPROTO_ICMP: 3399 if (xprth + 2 < skb->data || 3400 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3401 u8 *icmp; 3402 3403 xprth = skb_network_header(skb) + ihl * 4; 3404 icmp = xprth; 3405 3406 fl4->fl4_icmp_type = icmp[0]; 3407 fl4->fl4_icmp_code = icmp[1]; 3408 } 3409 break; 3410 case IPPROTO_GRE: 3411 if (xprth + 12 < skb->data || 3412 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3413 __be16 *greflags; 3414 __be32 *gre_hdr; 3415 3416 xprth = skb_network_header(skb) + ihl * 4; 3417 greflags = (__be16 *)xprth; 3418 gre_hdr = (__be32 *)xprth; 3419 3420 if (greflags[0] & GRE_KEY) { 3421 if (greflags[0] & GRE_CSUM) 3422 gre_hdr++; 3423 fl4->fl4_gre_key = gre_hdr[1]; 3424 } 3425 } 3426 break; 3427 default: 3428 break; 3429 } 3430 } 3431 } 3432 3433 #if IS_ENABLED(CONFIG_IPV6) 3434 static void 3435 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3436 { 3437 struct flowi6 *fl6 = &fl->u.ip6; 3438 int onlyproto = 0; 3439 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3440 u32 offset = sizeof(*hdr); 3441 struct ipv6_opt_hdr *exthdr; 3442 const unsigned char *nh = skb_network_header(skb); 3443 u16 nhoff = IP6CB(skb)->nhoff; 3444 int oif = 0; 3445 u8 nexthdr; 3446 3447 if (!nhoff) 3448 nhoff = offsetof(struct ipv6hdr, nexthdr); 3449 3450 nexthdr = nh[nhoff]; 3451 3452 if (skb_dst(skb) && skb_dst(skb)->dev) 3453 oif = skb_dst(skb)->dev->ifindex; 3454 3455 memset(fl6, 0, sizeof(struct flowi6)); 3456 fl6->flowi6_mark = skb->mark; 3457 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3458 3459 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3460 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3461 3462 while (nh + offset + sizeof(*exthdr) < skb->data || 3463 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3464 nh = skb_network_header(skb); 3465 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3466 3467 switch (nexthdr) { 3468 case NEXTHDR_FRAGMENT: 3469 onlyproto = 1; 3470 fallthrough; 3471 case NEXTHDR_ROUTING: 3472 case NEXTHDR_HOP: 3473 case NEXTHDR_DEST: 3474 offset += ipv6_optlen(exthdr); 3475 nexthdr = exthdr->nexthdr; 3476 break; 3477 case IPPROTO_UDP: 3478 case IPPROTO_UDPLITE: 3479 case IPPROTO_TCP: 3480 case IPPROTO_SCTP: 3481 case IPPROTO_DCCP: 3482 if (!onlyproto && (nh + offset + 4 < skb->data || 3483 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3484 __be16 *ports; 3485 3486 nh = skb_network_header(skb); 3487 ports = (__be16 *)(nh + offset); 3488 fl6->fl6_sport = ports[!!reverse]; 3489 fl6->fl6_dport = ports[!reverse]; 3490 } 3491 fl6->flowi6_proto = nexthdr; 3492 return; 3493 case IPPROTO_ICMPV6: 3494 if (!onlyproto && (nh + offset + 2 < skb->data || 3495 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3496 u8 *icmp; 3497 3498 nh = skb_network_header(skb); 3499 icmp = (u8 *)(nh + offset); 3500 fl6->fl6_icmp_type = icmp[0]; 3501 fl6->fl6_icmp_code = icmp[1]; 3502 } 3503 fl6->flowi6_proto = nexthdr; 3504 return; 3505 case IPPROTO_GRE: 3506 if (!onlyproto && 3507 (nh + offset + 12 < skb->data || 3508 pskb_may_pull(skb, nh + offset + 12 - skb->data))) { 3509 struct gre_base_hdr *gre_hdr; 3510 __be32 *gre_key; 3511 3512 nh = skb_network_header(skb); 3513 gre_hdr = (struct gre_base_hdr *)(nh + offset); 3514 gre_key = (__be32 *)(gre_hdr + 1); 3515 3516 if (gre_hdr->flags & GRE_KEY) { 3517 if (gre_hdr->flags & GRE_CSUM) 3518 gre_key++; 3519 fl6->fl6_gre_key = *gre_key; 3520 } 3521 } 3522 fl6->flowi6_proto = nexthdr; 3523 return; 3524 3525 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3526 case IPPROTO_MH: 3527 offset += ipv6_optlen(exthdr); 3528 if (!onlyproto && (nh + offset + 3 < skb->data || 3529 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3530 struct ip6_mh *mh; 3531 3532 nh = skb_network_header(skb); 3533 mh = (struct ip6_mh *)(nh + offset); 3534 fl6->fl6_mh_type = mh->ip6mh_type; 3535 } 3536 fl6->flowi6_proto = nexthdr; 3537 return; 3538 #endif 3539 default: 3540 fl6->flowi6_proto = nexthdr; 3541 return; 3542 } 3543 } 3544 } 3545 #endif 3546 3547 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3548 unsigned int family, int reverse) 3549 { 3550 switch (family) { 3551 case AF_INET: 3552 decode_session4(skb, fl, reverse); 3553 break; 3554 #if IS_ENABLED(CONFIG_IPV6) 3555 case AF_INET6: 3556 decode_session6(skb, fl, reverse); 3557 break; 3558 #endif 3559 default: 3560 return -EAFNOSUPPORT; 3561 } 3562 3563 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3564 } 3565 EXPORT_SYMBOL(__xfrm_decode_session); 3566 3567 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3568 { 3569 for (; k < sp->len; k++) { 3570 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3571 *idxp = k; 3572 return 1; 3573 } 3574 } 3575 3576 return 0; 3577 } 3578 3579 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3580 unsigned short family) 3581 { 3582 struct net *net = dev_net(skb->dev); 3583 struct xfrm_policy *pol; 3584 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3585 int npols = 0; 3586 int xfrm_nr; 3587 int pi; 3588 int reverse; 3589 struct flowi fl; 3590 int xerr_idx = -1; 3591 const struct xfrm_if_cb *ifcb; 3592 struct sec_path *sp; 3593 u32 if_id = 0; 3594 3595 rcu_read_lock(); 3596 ifcb = xfrm_if_get_cb(); 3597 3598 if (ifcb) { 3599 struct xfrm_if_decode_session_result r; 3600 3601 if (ifcb->decode_session(skb, family, &r)) { 3602 if_id = r.if_id; 3603 net = r.net; 3604 } 3605 } 3606 rcu_read_unlock(); 3607 3608 reverse = dir & ~XFRM_POLICY_MASK; 3609 dir &= XFRM_POLICY_MASK; 3610 3611 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3612 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3613 return 0; 3614 } 3615 3616 nf_nat_decode_session(skb, &fl, family); 3617 3618 /* First, check used SA against their selectors. */ 3619 sp = skb_sec_path(skb); 3620 if (sp) { 3621 int i; 3622 3623 for (i = sp->len - 1; i >= 0; i--) { 3624 struct xfrm_state *x = sp->xvec[i]; 3625 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3626 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3627 return 0; 3628 } 3629 } 3630 } 3631 3632 pol = NULL; 3633 sk = sk_to_full_sk(sk); 3634 if (sk && sk->sk_policy[dir]) { 3635 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3636 if (IS_ERR(pol)) { 3637 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3638 return 0; 3639 } 3640 } 3641 3642 if (!pol) 3643 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3644 3645 if (IS_ERR(pol)) { 3646 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3647 return 0; 3648 } 3649 3650 if (!pol) { 3651 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { 3652 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3653 return 0; 3654 } 3655 3656 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3657 xfrm_secpath_reject(xerr_idx, skb, &fl); 3658 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3659 return 0; 3660 } 3661 return 1; 3662 } 3663 3664 /* This lockless write can happen from different cpus. */ 3665 WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds()); 3666 3667 pols[0] = pol; 3668 npols++; 3669 #ifdef CONFIG_XFRM_SUB_POLICY 3670 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3671 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3672 &fl, family, 3673 XFRM_POLICY_IN, if_id); 3674 if (pols[1]) { 3675 if (IS_ERR(pols[1])) { 3676 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3677 xfrm_pol_put(pols[0]); 3678 return 0; 3679 } 3680 /* This write can happen from different cpus. */ 3681 WRITE_ONCE(pols[1]->curlft.use_time, 3682 ktime_get_real_seconds()); 3683 npols++; 3684 } 3685 } 3686 #endif 3687 3688 if (pol->action == XFRM_POLICY_ALLOW) { 3689 static struct sec_path dummy; 3690 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3691 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3692 struct xfrm_tmpl **tpp = tp; 3693 int ti = 0; 3694 int i, k; 3695 3696 sp = skb_sec_path(skb); 3697 if (!sp) 3698 sp = &dummy; 3699 3700 for (pi = 0; pi < npols; pi++) { 3701 if (pols[pi] != pol && 3702 pols[pi]->action != XFRM_POLICY_ALLOW) { 3703 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3704 goto reject; 3705 } 3706 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3707 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3708 goto reject_error; 3709 } 3710 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3711 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3712 } 3713 xfrm_nr = ti; 3714 3715 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK && 3716 !xfrm_nr) { 3717 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); 3718 goto reject; 3719 } 3720 3721 if (npols > 1) { 3722 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3723 tpp = stp; 3724 } 3725 3726 /* For each tunnel xfrm, find the first matching tmpl. 3727 * For each tmpl before that, find corresponding xfrm. 3728 * Order is _important_. Later we will implement 3729 * some barriers, but at the moment barriers 3730 * are implied between each two transformations. 3731 */ 3732 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3733 k = xfrm_policy_ok(tpp[i], sp, k, family); 3734 if (k < 0) { 3735 if (k < -1) 3736 /* "-2 - errored_index" returned */ 3737 xerr_idx = -(2+k); 3738 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3739 goto reject; 3740 } 3741 } 3742 3743 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3744 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3745 goto reject; 3746 } 3747 3748 if (if_id) 3749 secpath_reset(skb); 3750 3751 xfrm_pols_put(pols, npols); 3752 return 1; 3753 } 3754 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3755 3756 reject: 3757 xfrm_secpath_reject(xerr_idx, skb, &fl); 3758 reject_error: 3759 xfrm_pols_put(pols, npols); 3760 return 0; 3761 } 3762 EXPORT_SYMBOL(__xfrm_policy_check); 3763 3764 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3765 { 3766 struct net *net = dev_net(skb->dev); 3767 struct flowi fl; 3768 struct dst_entry *dst; 3769 int res = 1; 3770 3771 if (xfrm_decode_session(skb, &fl, family) < 0) { 3772 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3773 return 0; 3774 } 3775 3776 skb_dst_force(skb); 3777 if (!skb_dst(skb)) { 3778 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3779 return 0; 3780 } 3781 3782 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3783 if (IS_ERR(dst)) { 3784 res = 0; 3785 dst = NULL; 3786 } 3787 skb_dst_set(skb, dst); 3788 return res; 3789 } 3790 EXPORT_SYMBOL(__xfrm_route_forward); 3791 3792 /* Optimize later using cookies and generation ids. */ 3793 3794 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3795 { 3796 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3797 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3798 * get validated by dst_ops->check on every use. We do this 3799 * because when a normal route referenced by an XFRM dst is 3800 * obsoleted we do not go looking around for all parent 3801 * referencing XFRM dsts so that we can invalidate them. It 3802 * is just too much work. Instead we make the checks here on 3803 * every use. For example: 3804 * 3805 * XFRM dst A --> IPv4 dst X 3806 * 3807 * X is the "xdst->route" of A (X is also the "dst->path" of A 3808 * in this example). If X is marked obsolete, "A" will not 3809 * notice. That's what we are validating here via the 3810 * stale_bundle() check. 3811 * 3812 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3813 * be marked on it. 3814 * This will force stale_bundle() to fail on any xdst bundle with 3815 * this dst linked in it. 3816 */ 3817 if (dst->obsolete < 0 && !stale_bundle(dst)) 3818 return dst; 3819 3820 return NULL; 3821 } 3822 3823 static int stale_bundle(struct dst_entry *dst) 3824 { 3825 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3826 } 3827 3828 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3829 { 3830 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3831 dst->dev = blackhole_netdev; 3832 dev_hold(dst->dev); 3833 dev_put(dev); 3834 } 3835 } 3836 EXPORT_SYMBOL(xfrm_dst_ifdown); 3837 3838 static void xfrm_link_failure(struct sk_buff *skb) 3839 { 3840 /* Impossible. Such dst must be popped before reaches point of failure. */ 3841 } 3842 3843 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3844 { 3845 if (dst) { 3846 if (dst->obsolete) { 3847 dst_release(dst); 3848 dst = NULL; 3849 } 3850 } 3851 return dst; 3852 } 3853 3854 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3855 { 3856 while (nr--) { 3857 struct xfrm_dst *xdst = bundle[nr]; 3858 u32 pmtu, route_mtu_cached; 3859 struct dst_entry *dst; 3860 3861 dst = &xdst->u.dst; 3862 pmtu = dst_mtu(xfrm_dst_child(dst)); 3863 xdst->child_mtu_cached = pmtu; 3864 3865 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3866 3867 route_mtu_cached = dst_mtu(xdst->route); 3868 xdst->route_mtu_cached = route_mtu_cached; 3869 3870 if (pmtu > route_mtu_cached) 3871 pmtu = route_mtu_cached; 3872 3873 dst_metric_set(dst, RTAX_MTU, pmtu); 3874 } 3875 } 3876 3877 /* Check that the bundle accepts the flow and its components are 3878 * still valid. 3879 */ 3880 3881 static int xfrm_bundle_ok(struct xfrm_dst *first) 3882 { 3883 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3884 struct dst_entry *dst = &first->u.dst; 3885 struct xfrm_dst *xdst; 3886 int start_from, nr; 3887 u32 mtu; 3888 3889 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3890 (dst->dev && !netif_running(dst->dev))) 3891 return 0; 3892 3893 if (dst->flags & DST_XFRM_QUEUE) 3894 return 1; 3895 3896 start_from = nr = 0; 3897 do { 3898 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3899 3900 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3901 return 0; 3902 if (xdst->xfrm_genid != dst->xfrm->genid) 3903 return 0; 3904 if (xdst->num_pols > 0 && 3905 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3906 return 0; 3907 3908 bundle[nr++] = xdst; 3909 3910 mtu = dst_mtu(xfrm_dst_child(dst)); 3911 if (xdst->child_mtu_cached != mtu) { 3912 start_from = nr; 3913 xdst->child_mtu_cached = mtu; 3914 } 3915 3916 if (!dst_check(xdst->route, xdst->route_cookie)) 3917 return 0; 3918 mtu = dst_mtu(xdst->route); 3919 if (xdst->route_mtu_cached != mtu) { 3920 start_from = nr; 3921 xdst->route_mtu_cached = mtu; 3922 } 3923 3924 dst = xfrm_dst_child(dst); 3925 } while (dst->xfrm); 3926 3927 if (likely(!start_from)) 3928 return 1; 3929 3930 xdst = bundle[start_from - 1]; 3931 mtu = xdst->child_mtu_cached; 3932 while (start_from--) { 3933 dst = &xdst->u.dst; 3934 3935 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3936 if (mtu > xdst->route_mtu_cached) 3937 mtu = xdst->route_mtu_cached; 3938 dst_metric_set(dst, RTAX_MTU, mtu); 3939 if (!start_from) 3940 break; 3941 3942 xdst = bundle[start_from - 1]; 3943 xdst->child_mtu_cached = mtu; 3944 } 3945 3946 return 1; 3947 } 3948 3949 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3950 { 3951 return dst_metric_advmss(xfrm_dst_path(dst)); 3952 } 3953 3954 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3955 { 3956 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3957 3958 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3959 } 3960 3961 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3962 const void *daddr) 3963 { 3964 while (dst->xfrm) { 3965 const struct xfrm_state *xfrm = dst->xfrm; 3966 3967 dst = xfrm_dst_child(dst); 3968 3969 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3970 continue; 3971 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3972 daddr = xfrm->coaddr; 3973 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3974 daddr = &xfrm->id.daddr; 3975 } 3976 return daddr; 3977 } 3978 3979 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3980 struct sk_buff *skb, 3981 const void *daddr) 3982 { 3983 const struct dst_entry *path = xfrm_dst_path(dst); 3984 3985 if (!skb) 3986 daddr = xfrm_get_dst_nexthop(dst, daddr); 3987 return path->ops->neigh_lookup(path, skb, daddr); 3988 } 3989 3990 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3991 { 3992 const struct dst_entry *path = xfrm_dst_path(dst); 3993 3994 daddr = xfrm_get_dst_nexthop(dst, daddr); 3995 path->ops->confirm_neigh(path, daddr); 3996 } 3997 3998 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3999 { 4000 int err = 0; 4001 4002 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 4003 return -EAFNOSUPPORT; 4004 4005 spin_lock(&xfrm_policy_afinfo_lock); 4006 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 4007 err = -EEXIST; 4008 else { 4009 struct dst_ops *dst_ops = afinfo->dst_ops; 4010 if (likely(dst_ops->kmem_cachep == NULL)) 4011 dst_ops->kmem_cachep = xfrm_dst_cache; 4012 if (likely(dst_ops->check == NULL)) 4013 dst_ops->check = xfrm_dst_check; 4014 if (likely(dst_ops->default_advmss == NULL)) 4015 dst_ops->default_advmss = xfrm_default_advmss; 4016 if (likely(dst_ops->mtu == NULL)) 4017 dst_ops->mtu = xfrm_mtu; 4018 if (likely(dst_ops->negative_advice == NULL)) 4019 dst_ops->negative_advice = xfrm_negative_advice; 4020 if (likely(dst_ops->link_failure == NULL)) 4021 dst_ops->link_failure = xfrm_link_failure; 4022 if (likely(dst_ops->neigh_lookup == NULL)) 4023 dst_ops->neigh_lookup = xfrm_neigh_lookup; 4024 if (likely(!dst_ops->confirm_neigh)) 4025 dst_ops->confirm_neigh = xfrm_confirm_neigh; 4026 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 4027 } 4028 spin_unlock(&xfrm_policy_afinfo_lock); 4029 4030 return err; 4031 } 4032 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 4033 4034 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 4035 { 4036 struct dst_ops *dst_ops = afinfo->dst_ops; 4037 int i; 4038 4039 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 4040 if (xfrm_policy_afinfo[i] != afinfo) 4041 continue; 4042 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 4043 break; 4044 } 4045 4046 synchronize_rcu(); 4047 4048 dst_ops->kmem_cachep = NULL; 4049 dst_ops->check = NULL; 4050 dst_ops->negative_advice = NULL; 4051 dst_ops->link_failure = NULL; 4052 } 4053 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 4054 4055 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 4056 { 4057 spin_lock(&xfrm_if_cb_lock); 4058 rcu_assign_pointer(xfrm_if_cb, ifcb); 4059 spin_unlock(&xfrm_if_cb_lock); 4060 } 4061 EXPORT_SYMBOL(xfrm_if_register_cb); 4062 4063 void xfrm_if_unregister_cb(void) 4064 { 4065 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4066 synchronize_rcu(); 4067 } 4068 EXPORT_SYMBOL(xfrm_if_unregister_cb); 4069 4070 #ifdef CONFIG_XFRM_STATISTICS 4071 static int __net_init xfrm_statistics_init(struct net *net) 4072 { 4073 int rv; 4074 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 4075 if (!net->mib.xfrm_statistics) 4076 return -ENOMEM; 4077 rv = xfrm_proc_init(net); 4078 if (rv < 0) 4079 free_percpu(net->mib.xfrm_statistics); 4080 return rv; 4081 } 4082 4083 static void xfrm_statistics_fini(struct net *net) 4084 { 4085 xfrm_proc_fini(net); 4086 free_percpu(net->mib.xfrm_statistics); 4087 } 4088 #else 4089 static int __net_init xfrm_statistics_init(struct net *net) 4090 { 4091 return 0; 4092 } 4093 4094 static void xfrm_statistics_fini(struct net *net) 4095 { 4096 } 4097 #endif 4098 4099 static int __net_init xfrm_policy_init(struct net *net) 4100 { 4101 unsigned int hmask, sz; 4102 int dir, err; 4103 4104 if (net_eq(net, &init_net)) { 4105 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4106 sizeof(struct xfrm_dst), 4107 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4108 NULL); 4109 err = rhashtable_init(&xfrm_policy_inexact_table, 4110 &xfrm_pol_inexact_params); 4111 BUG_ON(err); 4112 } 4113 4114 hmask = 8 - 1; 4115 sz = (hmask+1) * sizeof(struct hlist_head); 4116 4117 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4118 if (!net->xfrm.policy_byidx) 4119 goto out_byidx; 4120 net->xfrm.policy_idx_hmask = hmask; 4121 4122 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4123 struct xfrm_policy_hash *htab; 4124 4125 net->xfrm.policy_count[dir] = 0; 4126 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4127 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4128 4129 htab = &net->xfrm.policy_bydst[dir]; 4130 htab->table = xfrm_hash_alloc(sz); 4131 if (!htab->table) 4132 goto out_bydst; 4133 htab->hmask = hmask; 4134 htab->dbits4 = 32; 4135 htab->sbits4 = 32; 4136 htab->dbits6 = 128; 4137 htab->sbits6 = 128; 4138 } 4139 net->xfrm.policy_hthresh.lbits4 = 32; 4140 net->xfrm.policy_hthresh.rbits4 = 32; 4141 net->xfrm.policy_hthresh.lbits6 = 128; 4142 net->xfrm.policy_hthresh.rbits6 = 128; 4143 4144 seqlock_init(&net->xfrm.policy_hthresh.lock); 4145 4146 INIT_LIST_HEAD(&net->xfrm.policy_all); 4147 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4148 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4149 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4150 return 0; 4151 4152 out_bydst: 4153 for (dir--; dir >= 0; dir--) { 4154 struct xfrm_policy_hash *htab; 4155 4156 htab = &net->xfrm.policy_bydst[dir]; 4157 xfrm_hash_free(htab->table, sz); 4158 } 4159 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4160 out_byidx: 4161 return -ENOMEM; 4162 } 4163 4164 static void xfrm_policy_fini(struct net *net) 4165 { 4166 struct xfrm_pol_inexact_bin *b, *t; 4167 unsigned int sz; 4168 int dir; 4169 4170 flush_work(&net->xfrm.policy_hash_work); 4171 #ifdef CONFIG_XFRM_SUB_POLICY 4172 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4173 #endif 4174 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4175 4176 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4177 4178 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4179 struct xfrm_policy_hash *htab; 4180 4181 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4182 4183 htab = &net->xfrm.policy_bydst[dir]; 4184 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4185 WARN_ON(!hlist_empty(htab->table)); 4186 xfrm_hash_free(htab->table, sz); 4187 } 4188 4189 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4190 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4191 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4192 4193 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4194 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4195 __xfrm_policy_inexact_prune_bin(b, true); 4196 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4197 } 4198 4199 static int __net_init xfrm_net_init(struct net *net) 4200 { 4201 int rv; 4202 4203 /* Initialize the per-net locks here */ 4204 spin_lock_init(&net->xfrm.xfrm_state_lock); 4205 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4206 seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock); 4207 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4208 net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT; 4209 net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT; 4210 net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT; 4211 4212 rv = xfrm_statistics_init(net); 4213 if (rv < 0) 4214 goto out_statistics; 4215 rv = xfrm_state_init(net); 4216 if (rv < 0) 4217 goto out_state; 4218 rv = xfrm_policy_init(net); 4219 if (rv < 0) 4220 goto out_policy; 4221 rv = xfrm_sysctl_init(net); 4222 if (rv < 0) 4223 goto out_sysctl; 4224 4225 return 0; 4226 4227 out_sysctl: 4228 xfrm_policy_fini(net); 4229 out_policy: 4230 xfrm_state_fini(net); 4231 out_state: 4232 xfrm_statistics_fini(net); 4233 out_statistics: 4234 return rv; 4235 } 4236 4237 static void __net_exit xfrm_net_exit(struct net *net) 4238 { 4239 xfrm_sysctl_fini(net); 4240 xfrm_policy_fini(net); 4241 xfrm_state_fini(net); 4242 xfrm_statistics_fini(net); 4243 } 4244 4245 static struct pernet_operations __net_initdata xfrm_net_ops = { 4246 .init = xfrm_net_init, 4247 .exit = xfrm_net_exit, 4248 }; 4249 4250 void __init xfrm_init(void) 4251 { 4252 register_pernet_subsys(&xfrm_net_ops); 4253 xfrm_dev_init(); 4254 xfrm_input_init(); 4255 4256 #ifdef CONFIG_XFRM_ESPINTCP 4257 espintcp_init(); 4258 #endif 4259 } 4260 4261 #ifdef CONFIG_AUDITSYSCALL 4262 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4263 struct audit_buffer *audit_buf) 4264 { 4265 struct xfrm_sec_ctx *ctx = xp->security; 4266 struct xfrm_selector *sel = &xp->selector; 4267 4268 if (ctx) 4269 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4270 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4271 4272 switch (sel->family) { 4273 case AF_INET: 4274 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4275 if (sel->prefixlen_s != 32) 4276 audit_log_format(audit_buf, " src_prefixlen=%d", 4277 sel->prefixlen_s); 4278 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4279 if (sel->prefixlen_d != 32) 4280 audit_log_format(audit_buf, " dst_prefixlen=%d", 4281 sel->prefixlen_d); 4282 break; 4283 case AF_INET6: 4284 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4285 if (sel->prefixlen_s != 128) 4286 audit_log_format(audit_buf, " src_prefixlen=%d", 4287 sel->prefixlen_s); 4288 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4289 if (sel->prefixlen_d != 128) 4290 audit_log_format(audit_buf, " dst_prefixlen=%d", 4291 sel->prefixlen_d); 4292 break; 4293 } 4294 } 4295 4296 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4297 { 4298 struct audit_buffer *audit_buf; 4299 4300 audit_buf = xfrm_audit_start("SPD-add"); 4301 if (audit_buf == NULL) 4302 return; 4303 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4304 audit_log_format(audit_buf, " res=%u", result); 4305 xfrm_audit_common_policyinfo(xp, audit_buf); 4306 audit_log_end(audit_buf); 4307 } 4308 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4309 4310 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4311 bool task_valid) 4312 { 4313 struct audit_buffer *audit_buf; 4314 4315 audit_buf = xfrm_audit_start("SPD-delete"); 4316 if (audit_buf == NULL) 4317 return; 4318 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4319 audit_log_format(audit_buf, " res=%u", result); 4320 xfrm_audit_common_policyinfo(xp, audit_buf); 4321 audit_log_end(audit_buf); 4322 } 4323 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4324 #endif 4325 4326 #ifdef CONFIG_XFRM_MIGRATE 4327 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4328 const struct xfrm_selector *sel_tgt) 4329 { 4330 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4331 if (sel_tgt->family == sel_cmp->family && 4332 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4333 sel_cmp->family) && 4334 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4335 sel_cmp->family) && 4336 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4337 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4338 return true; 4339 } 4340 } else { 4341 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4342 return true; 4343 } 4344 } 4345 return false; 4346 } 4347 4348 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4349 u8 dir, u8 type, struct net *net, u32 if_id) 4350 { 4351 struct xfrm_policy *pol, *ret = NULL; 4352 struct hlist_head *chain; 4353 u32 priority = ~0U; 4354 4355 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4356 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4357 hlist_for_each_entry(pol, chain, bydst) { 4358 if ((if_id == 0 || pol->if_id == if_id) && 4359 xfrm_migrate_selector_match(sel, &pol->selector) && 4360 pol->type == type) { 4361 ret = pol; 4362 priority = ret->priority; 4363 break; 4364 } 4365 } 4366 chain = &net->xfrm.policy_inexact[dir]; 4367 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4368 if ((pol->priority >= priority) && ret) 4369 break; 4370 4371 if ((if_id == 0 || pol->if_id == if_id) && 4372 xfrm_migrate_selector_match(sel, &pol->selector) && 4373 pol->type == type) { 4374 ret = pol; 4375 break; 4376 } 4377 } 4378 4379 xfrm_pol_hold(ret); 4380 4381 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4382 4383 return ret; 4384 } 4385 4386 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4387 { 4388 int match = 0; 4389 4390 if (t->mode == m->mode && t->id.proto == m->proto && 4391 (m->reqid == 0 || t->reqid == m->reqid)) { 4392 switch (t->mode) { 4393 case XFRM_MODE_TUNNEL: 4394 case XFRM_MODE_BEET: 4395 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4396 m->old_family) && 4397 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4398 m->old_family)) { 4399 match = 1; 4400 } 4401 break; 4402 case XFRM_MODE_TRANSPORT: 4403 /* in case of transport mode, template does not store 4404 any IP addresses, hence we just compare mode and 4405 protocol */ 4406 match = 1; 4407 break; 4408 default: 4409 break; 4410 } 4411 } 4412 return match; 4413 } 4414 4415 /* update endpoint address(es) of template(s) */ 4416 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4417 struct xfrm_migrate *m, int num_migrate, 4418 struct netlink_ext_ack *extack) 4419 { 4420 struct xfrm_migrate *mp; 4421 int i, j, n = 0; 4422 4423 write_lock_bh(&pol->lock); 4424 if (unlikely(pol->walk.dead)) { 4425 /* target policy has been deleted */ 4426 NL_SET_ERR_MSG(extack, "Target policy not found"); 4427 write_unlock_bh(&pol->lock); 4428 return -ENOENT; 4429 } 4430 4431 for (i = 0; i < pol->xfrm_nr; i++) { 4432 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4433 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4434 continue; 4435 n++; 4436 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4437 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4438 continue; 4439 /* update endpoints */ 4440 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4441 sizeof(pol->xfrm_vec[i].id.daddr)); 4442 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4443 sizeof(pol->xfrm_vec[i].saddr)); 4444 pol->xfrm_vec[i].encap_family = mp->new_family; 4445 /* flush bundles */ 4446 atomic_inc(&pol->genid); 4447 } 4448 } 4449 4450 write_unlock_bh(&pol->lock); 4451 4452 if (!n) 4453 return -ENODATA; 4454 4455 return 0; 4456 } 4457 4458 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate, 4459 struct netlink_ext_ack *extack) 4460 { 4461 int i, j; 4462 4463 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) { 4464 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)"); 4465 return -EINVAL; 4466 } 4467 4468 for (i = 0; i < num_migrate; i++) { 4469 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4470 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) { 4471 NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null"); 4472 return -EINVAL; 4473 } 4474 4475 /* check if there is any duplicated entry */ 4476 for (j = i + 1; j < num_migrate; j++) { 4477 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4478 sizeof(m[i].old_daddr)) && 4479 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4480 sizeof(m[i].old_saddr)) && 4481 m[i].proto == m[j].proto && 4482 m[i].mode == m[j].mode && 4483 m[i].reqid == m[j].reqid && 4484 m[i].old_family == m[j].old_family) { 4485 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique"); 4486 return -EINVAL; 4487 } 4488 } 4489 } 4490 4491 return 0; 4492 } 4493 4494 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4495 struct xfrm_migrate *m, int num_migrate, 4496 struct xfrm_kmaddress *k, struct net *net, 4497 struct xfrm_encap_tmpl *encap, u32 if_id, 4498 struct netlink_ext_ack *extack) 4499 { 4500 int i, err, nx_cur = 0, nx_new = 0; 4501 struct xfrm_policy *pol = NULL; 4502 struct xfrm_state *x, *xc; 4503 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4504 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4505 struct xfrm_migrate *mp; 4506 4507 /* Stage 0 - sanity checks */ 4508 err = xfrm_migrate_check(m, num_migrate, extack); 4509 if (err < 0) 4510 goto out; 4511 4512 if (dir >= XFRM_POLICY_MAX) { 4513 NL_SET_ERR_MSG(extack, "Invalid policy direction"); 4514 err = -EINVAL; 4515 goto out; 4516 } 4517 4518 /* Stage 1 - find policy */ 4519 pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id); 4520 if (!pol) { 4521 NL_SET_ERR_MSG(extack, "Target policy not found"); 4522 err = -ENOENT; 4523 goto out; 4524 } 4525 4526 /* Stage 2 - find and update state(s) */ 4527 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4528 if ((x = xfrm_migrate_state_find(mp, net, if_id))) { 4529 x_cur[nx_cur] = x; 4530 nx_cur++; 4531 xc = xfrm_state_migrate(x, mp, encap); 4532 if (xc) { 4533 x_new[nx_new] = xc; 4534 nx_new++; 4535 } else { 4536 err = -ENODATA; 4537 goto restore_state; 4538 } 4539 } 4540 } 4541 4542 /* Stage 3 - update policy */ 4543 err = xfrm_policy_migrate(pol, m, num_migrate, extack); 4544 if (err < 0) 4545 goto restore_state; 4546 4547 /* Stage 4 - delete old state(s) */ 4548 if (nx_cur) { 4549 xfrm_states_put(x_cur, nx_cur); 4550 xfrm_states_delete(x_cur, nx_cur); 4551 } 4552 4553 /* Stage 5 - announce */ 4554 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4555 4556 xfrm_pol_put(pol); 4557 4558 return 0; 4559 out: 4560 return err; 4561 4562 restore_state: 4563 if (pol) 4564 xfrm_pol_put(pol); 4565 if (nx_cur) 4566 xfrm_states_put(x_cur, nx_cur); 4567 if (nx_new) 4568 xfrm_states_delete(x_new, nx_new); 4569 4570 return err; 4571 } 4572 EXPORT_SYMBOL(xfrm_migrate); 4573 #endif 4574