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(int family, 255 const struct xfrm_dst_lookup_params *params) 256 { 257 const struct xfrm_policy_afinfo *afinfo; 258 struct dst_entry *dst; 259 260 afinfo = xfrm_policy_get_afinfo(family); 261 if (unlikely(afinfo == NULL)) 262 return ERR_PTR(-EAFNOSUPPORT); 263 264 dst = afinfo->dst_lookup(params); 265 266 rcu_read_unlock(); 267 268 return dst; 269 } 270 EXPORT_SYMBOL(__xfrm_dst_lookup); 271 272 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 273 int tos, int oif, 274 xfrm_address_t *prev_saddr, 275 xfrm_address_t *prev_daddr, 276 int family, u32 mark) 277 { 278 struct xfrm_dst_lookup_params params; 279 struct net *net = xs_net(x); 280 xfrm_address_t *saddr = &x->props.saddr; 281 xfrm_address_t *daddr = &x->id.daddr; 282 struct dst_entry *dst; 283 284 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 285 saddr = x->coaddr; 286 daddr = prev_daddr; 287 } 288 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 289 saddr = prev_saddr; 290 daddr = x->coaddr; 291 } 292 293 params.net = net; 294 params.saddr = saddr; 295 params.daddr = daddr; 296 params.tos = tos; 297 params.oif = oif; 298 params.mark = mark; 299 params.ipproto = x->id.proto; 300 if (x->encap) { 301 switch (x->encap->encap_type) { 302 case UDP_ENCAP_ESPINUDP: 303 params.ipproto = IPPROTO_UDP; 304 params.uli.ports.sport = x->encap->encap_sport; 305 params.uli.ports.dport = x->encap->encap_dport; 306 break; 307 case TCP_ENCAP_ESPINTCP: 308 params.ipproto = IPPROTO_TCP; 309 params.uli.ports.sport = x->encap->encap_sport; 310 params.uli.ports.dport = x->encap->encap_dport; 311 break; 312 } 313 } 314 315 dst = __xfrm_dst_lookup(family, ¶ms); 316 317 if (!IS_ERR(dst)) { 318 if (prev_saddr != saddr) 319 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 320 if (prev_daddr != daddr) 321 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 322 } 323 324 return dst; 325 } 326 327 static inline unsigned long make_jiffies(long secs) 328 { 329 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 330 return MAX_SCHEDULE_TIMEOUT-1; 331 else 332 return secs*HZ; 333 } 334 335 static void xfrm_policy_timer(struct timer_list *t) 336 { 337 struct xfrm_policy *xp = from_timer(xp, t, timer); 338 time64_t now = ktime_get_real_seconds(); 339 time64_t next = TIME64_MAX; 340 int warn = 0; 341 int dir; 342 343 read_lock(&xp->lock); 344 345 if (unlikely(xp->walk.dead)) 346 goto out; 347 348 dir = xfrm_policy_id2dir(xp->index); 349 350 if (xp->lft.hard_add_expires_seconds) { 351 time64_t tmo = xp->lft.hard_add_expires_seconds + 352 xp->curlft.add_time - now; 353 if (tmo <= 0) 354 goto expired; 355 if (tmo < next) 356 next = tmo; 357 } 358 if (xp->lft.hard_use_expires_seconds) { 359 time64_t tmo = xp->lft.hard_use_expires_seconds + 360 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now; 361 if (tmo <= 0) 362 goto expired; 363 if (tmo < next) 364 next = tmo; 365 } 366 if (xp->lft.soft_add_expires_seconds) { 367 time64_t tmo = xp->lft.soft_add_expires_seconds + 368 xp->curlft.add_time - now; 369 if (tmo <= 0) { 370 warn = 1; 371 tmo = XFRM_KM_TIMEOUT; 372 } 373 if (tmo < next) 374 next = tmo; 375 } 376 if (xp->lft.soft_use_expires_seconds) { 377 time64_t tmo = xp->lft.soft_use_expires_seconds + 378 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now; 379 if (tmo <= 0) { 380 warn = 1; 381 tmo = XFRM_KM_TIMEOUT; 382 } 383 if (tmo < next) 384 next = tmo; 385 } 386 387 if (warn) 388 km_policy_expired(xp, dir, 0, 0); 389 if (next != TIME64_MAX && 390 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 391 xfrm_pol_hold(xp); 392 393 out: 394 read_unlock(&xp->lock); 395 xfrm_pol_put(xp); 396 return; 397 398 expired: 399 read_unlock(&xp->lock); 400 if (!xfrm_policy_delete(xp, dir)) 401 km_policy_expired(xp, dir, 1, 0); 402 xfrm_pol_put(xp); 403 } 404 405 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 406 * SPD calls. 407 */ 408 409 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 410 { 411 struct xfrm_policy *policy; 412 413 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 414 415 if (policy) { 416 write_pnet(&policy->xp_net, net); 417 INIT_LIST_HEAD(&policy->walk.all); 418 INIT_HLIST_NODE(&policy->bydst_inexact_list); 419 INIT_HLIST_NODE(&policy->bydst); 420 INIT_HLIST_NODE(&policy->byidx); 421 rwlock_init(&policy->lock); 422 refcount_set(&policy->refcnt, 1); 423 skb_queue_head_init(&policy->polq.hold_queue); 424 timer_setup(&policy->timer, xfrm_policy_timer, 0); 425 timer_setup(&policy->polq.hold_timer, 426 xfrm_policy_queue_process, 0); 427 } 428 return policy; 429 } 430 EXPORT_SYMBOL(xfrm_policy_alloc); 431 432 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 433 { 434 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 435 436 security_xfrm_policy_free(policy->security); 437 kfree(policy); 438 } 439 440 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 441 442 void xfrm_policy_destroy(struct xfrm_policy *policy) 443 { 444 BUG_ON(!policy->walk.dead); 445 446 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 447 BUG(); 448 449 xfrm_dev_policy_free(policy); 450 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 451 } 452 EXPORT_SYMBOL(xfrm_policy_destroy); 453 454 /* Rule must be locked. Release descendant resources, announce 455 * entry dead. The rule must be unlinked from lists to the moment. 456 */ 457 458 static void xfrm_policy_kill(struct xfrm_policy *policy) 459 { 460 xfrm_dev_policy_delete(policy); 461 462 write_lock_bh(&policy->lock); 463 policy->walk.dead = 1; 464 write_unlock_bh(&policy->lock); 465 466 atomic_inc(&policy->genid); 467 468 if (del_timer(&policy->polq.hold_timer)) 469 xfrm_pol_put(policy); 470 skb_queue_purge(&policy->polq.hold_queue); 471 472 if (del_timer(&policy->timer)) 473 xfrm_pol_put(policy); 474 475 xfrm_pol_put(policy); 476 } 477 478 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 479 480 static inline unsigned int idx_hash(struct net *net, u32 index) 481 { 482 return __idx_hash(index, net->xfrm.policy_idx_hmask); 483 } 484 485 /* calculate policy hash thresholds */ 486 static void __get_hash_thresh(struct net *net, 487 unsigned short family, int dir, 488 u8 *dbits, u8 *sbits) 489 { 490 switch (family) { 491 case AF_INET: 492 *dbits = net->xfrm.policy_bydst[dir].dbits4; 493 *sbits = net->xfrm.policy_bydst[dir].sbits4; 494 break; 495 496 case AF_INET6: 497 *dbits = net->xfrm.policy_bydst[dir].dbits6; 498 *sbits = net->xfrm.policy_bydst[dir].sbits6; 499 break; 500 501 default: 502 *dbits = 0; 503 *sbits = 0; 504 } 505 } 506 507 static struct hlist_head *policy_hash_bysel(struct net *net, 508 const struct xfrm_selector *sel, 509 unsigned short family, int dir) 510 { 511 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 512 unsigned int hash; 513 u8 dbits; 514 u8 sbits; 515 516 __get_hash_thresh(net, family, dir, &dbits, &sbits); 517 hash = __sel_hash(sel, family, hmask, dbits, sbits); 518 519 if (hash == hmask + 1) 520 return NULL; 521 522 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 523 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 524 } 525 526 static struct hlist_head *policy_hash_direct(struct net *net, 527 const xfrm_address_t *daddr, 528 const xfrm_address_t *saddr, 529 unsigned short family, int dir) 530 { 531 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 532 unsigned int hash; 533 u8 dbits; 534 u8 sbits; 535 536 __get_hash_thresh(net, family, dir, &dbits, &sbits); 537 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 538 539 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 540 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 541 } 542 543 static void xfrm_dst_hash_transfer(struct net *net, 544 struct hlist_head *list, 545 struct hlist_head *ndsttable, 546 unsigned int nhashmask, 547 int dir) 548 { 549 struct hlist_node *tmp, *entry0 = NULL; 550 struct xfrm_policy *pol; 551 unsigned int h0 = 0; 552 u8 dbits; 553 u8 sbits; 554 555 redo: 556 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 557 unsigned int h; 558 559 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 560 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 561 pol->family, nhashmask, dbits, sbits); 562 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) { 563 hlist_del_rcu(&pol->bydst); 564 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 565 h0 = h; 566 } else { 567 if (h != h0) 568 continue; 569 hlist_del_rcu(&pol->bydst); 570 hlist_add_behind_rcu(&pol->bydst, entry0); 571 } 572 entry0 = &pol->bydst; 573 } 574 if (!hlist_empty(list)) { 575 entry0 = NULL; 576 goto redo; 577 } 578 } 579 580 static void xfrm_idx_hash_transfer(struct hlist_head *list, 581 struct hlist_head *nidxtable, 582 unsigned int nhashmask) 583 { 584 struct hlist_node *tmp; 585 struct xfrm_policy *pol; 586 587 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 588 unsigned int h; 589 590 h = __idx_hash(pol->index, nhashmask); 591 hlist_add_head(&pol->byidx, nidxtable+h); 592 } 593 } 594 595 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 596 { 597 return ((old_hmask + 1) << 1) - 1; 598 } 599 600 static void xfrm_bydst_resize(struct net *net, int dir) 601 { 602 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 603 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 604 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 605 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 606 struct hlist_head *odst; 607 int i; 608 609 if (!ndst) 610 return; 611 612 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 613 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 614 615 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 616 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 617 618 for (i = hmask; i >= 0; i--) 619 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 620 621 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 622 net->xfrm.policy_bydst[dir].hmask = nhashmask; 623 624 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 625 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 626 627 synchronize_rcu(); 628 629 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 630 } 631 632 static void xfrm_byidx_resize(struct net *net) 633 { 634 unsigned int hmask = net->xfrm.policy_idx_hmask; 635 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 636 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 637 struct hlist_head *oidx = net->xfrm.policy_byidx; 638 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 639 int i; 640 641 if (!nidx) 642 return; 643 644 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 645 646 for (i = hmask; i >= 0; i--) 647 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 648 649 net->xfrm.policy_byidx = nidx; 650 net->xfrm.policy_idx_hmask = nhashmask; 651 652 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 653 654 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 655 } 656 657 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 658 { 659 unsigned int cnt = net->xfrm.policy_count[dir]; 660 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 661 662 if (total) 663 *total += cnt; 664 665 if ((hmask + 1) < xfrm_policy_hashmax && 666 cnt > hmask) 667 return 1; 668 669 return 0; 670 } 671 672 static inline int xfrm_byidx_should_resize(struct net *net, int total) 673 { 674 unsigned int hmask = net->xfrm.policy_idx_hmask; 675 676 if ((hmask + 1) < xfrm_policy_hashmax && 677 total > hmask) 678 return 1; 679 680 return 0; 681 } 682 683 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 684 { 685 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 686 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 687 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 688 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 689 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 690 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 691 si->spdhcnt = net->xfrm.policy_idx_hmask; 692 si->spdhmcnt = xfrm_policy_hashmax; 693 } 694 EXPORT_SYMBOL(xfrm_spd_getinfo); 695 696 static DEFINE_MUTEX(hash_resize_mutex); 697 static void xfrm_hash_resize(struct work_struct *work) 698 { 699 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 700 int dir, total; 701 702 mutex_lock(&hash_resize_mutex); 703 704 total = 0; 705 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 706 if (xfrm_bydst_should_resize(net, dir, &total)) 707 xfrm_bydst_resize(net, dir); 708 } 709 if (xfrm_byidx_should_resize(net, total)) 710 xfrm_byidx_resize(net); 711 712 mutex_unlock(&hash_resize_mutex); 713 } 714 715 /* Make sure *pol can be inserted into fastbin. 716 * Useful to check that later insert requests will be successful 717 * (provided xfrm_policy_lock is held throughout). 718 */ 719 static struct xfrm_pol_inexact_bin * 720 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) 721 { 722 struct xfrm_pol_inexact_bin *bin, *prev; 723 struct xfrm_pol_inexact_key k = { 724 .family = pol->family, 725 .type = pol->type, 726 .dir = dir, 727 .if_id = pol->if_id, 728 }; 729 struct net *net = xp_net(pol); 730 731 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 732 733 write_pnet(&k.net, net); 734 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, 735 xfrm_pol_inexact_params); 736 if (bin) 737 return bin; 738 739 bin = kzalloc(sizeof(*bin), GFP_ATOMIC); 740 if (!bin) 741 return NULL; 742 743 bin->k = k; 744 INIT_HLIST_HEAD(&bin->hhead); 745 bin->root_d = RB_ROOT; 746 bin->root_s = RB_ROOT; 747 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); 748 749 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, 750 &bin->k, &bin->head, 751 xfrm_pol_inexact_params); 752 if (!prev) { 753 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); 754 return bin; 755 } 756 757 kfree(bin); 758 759 return IS_ERR(prev) ? NULL : prev; 760 } 761 762 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, 763 int family, u8 prefixlen) 764 { 765 if (xfrm_addr_any(addr, family)) 766 return true; 767 768 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) 769 return true; 770 771 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) 772 return true; 773 774 return false; 775 } 776 777 static bool 778 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) 779 { 780 const xfrm_address_t *addr; 781 bool saddr_any, daddr_any; 782 u8 prefixlen; 783 784 addr = &policy->selector.saddr; 785 prefixlen = policy->selector.prefixlen_s; 786 787 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 788 policy->family, 789 prefixlen); 790 addr = &policy->selector.daddr; 791 prefixlen = policy->selector.prefixlen_d; 792 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 793 policy->family, 794 prefixlen); 795 return saddr_any && daddr_any; 796 } 797 798 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, 799 const xfrm_address_t *addr, u8 prefixlen) 800 { 801 node->addr = *addr; 802 node->prefixlen = prefixlen; 803 } 804 805 static struct xfrm_pol_inexact_node * 806 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) 807 { 808 struct xfrm_pol_inexact_node *node; 809 810 node = kzalloc(sizeof(*node), GFP_ATOMIC); 811 if (node) 812 xfrm_pol_inexact_node_init(node, addr, prefixlen); 813 814 return node; 815 } 816 817 static int xfrm_policy_addr_delta(const xfrm_address_t *a, 818 const xfrm_address_t *b, 819 u8 prefixlen, u16 family) 820 { 821 u32 ma, mb, mask; 822 unsigned int pdw, pbi; 823 int delta = 0; 824 825 switch (family) { 826 case AF_INET: 827 if (prefixlen == 0) 828 return 0; 829 mask = ~0U << (32 - prefixlen); 830 ma = ntohl(a->a4) & mask; 831 mb = ntohl(b->a4) & mask; 832 if (ma < mb) 833 delta = -1; 834 else if (ma > mb) 835 delta = 1; 836 break; 837 case AF_INET6: 838 pdw = prefixlen >> 5; 839 pbi = prefixlen & 0x1f; 840 841 if (pdw) { 842 delta = memcmp(a->a6, b->a6, pdw << 2); 843 if (delta) 844 return delta; 845 } 846 if (pbi) { 847 mask = ~0U << (32 - pbi); 848 ma = ntohl(a->a6[pdw]) & mask; 849 mb = ntohl(b->a6[pdw]) & mask; 850 if (ma < mb) 851 delta = -1; 852 else if (ma > mb) 853 delta = 1; 854 } 855 break; 856 default: 857 break; 858 } 859 860 return delta; 861 } 862 863 static void xfrm_policy_inexact_list_reinsert(struct net *net, 864 struct xfrm_pol_inexact_node *n, 865 u16 family) 866 { 867 unsigned int matched_s, matched_d; 868 struct xfrm_policy *policy, *p; 869 870 matched_s = 0; 871 matched_d = 0; 872 873 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 874 struct hlist_node *newpos = NULL; 875 bool matches_s, matches_d; 876 877 if (policy->walk.dead || !policy->bydst_reinsert) 878 continue; 879 880 WARN_ON_ONCE(policy->family != family); 881 882 policy->bydst_reinsert = false; 883 hlist_for_each_entry(p, &n->hhead, bydst) { 884 if (policy->priority > p->priority) 885 newpos = &p->bydst; 886 else if (policy->priority == p->priority && 887 policy->pos > p->pos) 888 newpos = &p->bydst; 889 else 890 break; 891 } 892 893 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 894 hlist_add_behind_rcu(&policy->bydst, newpos); 895 else 896 hlist_add_head_rcu(&policy->bydst, &n->hhead); 897 898 /* paranoia checks follow. 899 * Check that the reinserted policy matches at least 900 * saddr or daddr for current node prefix. 901 * 902 * Matching both is fine, matching saddr in one policy 903 * (but not daddr) and then matching only daddr in another 904 * is a bug. 905 */ 906 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 907 &n->addr, 908 n->prefixlen, 909 family) == 0; 910 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 911 &n->addr, 912 n->prefixlen, 913 family) == 0; 914 if (matches_s && matches_d) 915 continue; 916 917 WARN_ON_ONCE(!matches_s && !matches_d); 918 if (matches_s) 919 matched_s++; 920 if (matches_d) 921 matched_d++; 922 WARN_ON_ONCE(matched_s && matched_d); 923 } 924 } 925 926 static void xfrm_policy_inexact_node_reinsert(struct net *net, 927 struct xfrm_pol_inexact_node *n, 928 struct rb_root *new, 929 u16 family) 930 { 931 struct xfrm_pol_inexact_node *node; 932 struct rb_node **p, *parent; 933 934 /* we should not have another subtree here */ 935 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 936 restart: 937 parent = NULL; 938 p = &new->rb_node; 939 while (*p) { 940 u8 prefixlen; 941 int delta; 942 943 parent = *p; 944 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 945 946 prefixlen = min(node->prefixlen, n->prefixlen); 947 948 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 949 prefixlen, family); 950 if (delta < 0) { 951 p = &parent->rb_left; 952 } else if (delta > 0) { 953 p = &parent->rb_right; 954 } else { 955 bool same_prefixlen = node->prefixlen == n->prefixlen; 956 struct xfrm_policy *tmp; 957 958 hlist_for_each_entry(tmp, &n->hhead, bydst) { 959 tmp->bydst_reinsert = true; 960 hlist_del_rcu(&tmp->bydst); 961 } 962 963 node->prefixlen = prefixlen; 964 965 xfrm_policy_inexact_list_reinsert(net, node, family); 966 967 if (same_prefixlen) { 968 kfree_rcu(n, rcu); 969 return; 970 } 971 972 rb_erase(*p, new); 973 kfree_rcu(n, rcu); 974 n = node; 975 goto restart; 976 } 977 } 978 979 rb_link_node_rcu(&n->node, parent, p); 980 rb_insert_color(&n->node, new); 981 } 982 983 /* merge nodes v and n */ 984 static void xfrm_policy_inexact_node_merge(struct net *net, 985 struct xfrm_pol_inexact_node *v, 986 struct xfrm_pol_inexact_node *n, 987 u16 family) 988 { 989 struct xfrm_pol_inexact_node *node; 990 struct xfrm_policy *tmp; 991 struct rb_node *rnode; 992 993 /* To-be-merged node v has a subtree. 994 * 995 * Dismantle it and insert its nodes to n->root. 996 */ 997 while ((rnode = rb_first(&v->root)) != NULL) { 998 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 999 rb_erase(&node->node, &v->root); 1000 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 1001 family); 1002 } 1003 1004 hlist_for_each_entry(tmp, &v->hhead, bydst) { 1005 tmp->bydst_reinsert = true; 1006 hlist_del_rcu(&tmp->bydst); 1007 } 1008 1009 xfrm_policy_inexact_list_reinsert(net, n, family); 1010 } 1011 1012 static struct xfrm_pol_inexact_node * 1013 xfrm_policy_inexact_insert_node(struct net *net, 1014 struct rb_root *root, 1015 xfrm_address_t *addr, 1016 u16 family, u8 prefixlen, u8 dir) 1017 { 1018 struct xfrm_pol_inexact_node *cached = NULL; 1019 struct rb_node **p, *parent = NULL; 1020 struct xfrm_pol_inexact_node *node; 1021 1022 p = &root->rb_node; 1023 while (*p) { 1024 int delta; 1025 1026 parent = *p; 1027 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 1028 1029 delta = xfrm_policy_addr_delta(addr, &node->addr, 1030 node->prefixlen, 1031 family); 1032 if (delta == 0 && prefixlen >= node->prefixlen) { 1033 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 1034 return node; 1035 } 1036 1037 if (delta < 0) 1038 p = &parent->rb_left; 1039 else 1040 p = &parent->rb_right; 1041 1042 if (prefixlen < node->prefixlen) { 1043 delta = xfrm_policy_addr_delta(addr, &node->addr, 1044 prefixlen, 1045 family); 1046 if (delta) 1047 continue; 1048 1049 /* This node is a subnet of the new prefix. It needs 1050 * to be removed and re-inserted with the smaller 1051 * prefix and all nodes that are now also covered 1052 * by the reduced prefixlen. 1053 */ 1054 rb_erase(&node->node, root); 1055 1056 if (!cached) { 1057 xfrm_pol_inexact_node_init(node, addr, 1058 prefixlen); 1059 cached = node; 1060 } else { 1061 /* This node also falls within the new 1062 * prefixlen. Merge the to-be-reinserted 1063 * node and this one. 1064 */ 1065 xfrm_policy_inexact_node_merge(net, node, 1066 cached, family); 1067 kfree_rcu(node, rcu); 1068 } 1069 1070 /* restart */ 1071 p = &root->rb_node; 1072 parent = NULL; 1073 } 1074 } 1075 1076 node = cached; 1077 if (!node) { 1078 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1079 if (!node) 1080 return NULL; 1081 } 1082 1083 rb_link_node_rcu(&node->node, parent, p); 1084 rb_insert_color(&node->node, root); 1085 1086 return node; 1087 } 1088 1089 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1090 { 1091 struct xfrm_pol_inexact_node *node; 1092 struct rb_node *rn = rb_first(r); 1093 1094 while (rn) { 1095 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1096 1097 xfrm_policy_inexact_gc_tree(&node->root, rm); 1098 rn = rb_next(rn); 1099 1100 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1101 WARN_ON_ONCE(rm); 1102 continue; 1103 } 1104 1105 rb_erase(&node->node, r); 1106 kfree_rcu(node, rcu); 1107 } 1108 } 1109 1110 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1111 { 1112 write_seqcount_begin(&b->count); 1113 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1114 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1115 write_seqcount_end(&b->count); 1116 1117 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1118 !hlist_empty(&b->hhead)) { 1119 WARN_ON_ONCE(net_exit); 1120 return; 1121 } 1122 1123 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1124 xfrm_pol_inexact_params) == 0) { 1125 list_del(&b->inexact_bins); 1126 kfree_rcu(b, rcu); 1127 } 1128 } 1129 1130 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1131 { 1132 struct net *net = read_pnet(&b->k.net); 1133 1134 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1135 __xfrm_policy_inexact_prune_bin(b, false); 1136 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1137 } 1138 1139 static void __xfrm_policy_inexact_flush(struct net *net) 1140 { 1141 struct xfrm_pol_inexact_bin *bin, *t; 1142 1143 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1144 1145 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1146 __xfrm_policy_inexact_prune_bin(bin, false); 1147 } 1148 1149 static struct hlist_head * 1150 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1151 struct xfrm_policy *policy, u8 dir) 1152 { 1153 struct xfrm_pol_inexact_node *n; 1154 struct net *net; 1155 1156 net = xp_net(policy); 1157 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1158 1159 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1160 return &bin->hhead; 1161 1162 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1163 policy->family, 1164 policy->selector.prefixlen_d)) { 1165 write_seqcount_begin(&bin->count); 1166 n = xfrm_policy_inexact_insert_node(net, 1167 &bin->root_s, 1168 &policy->selector.saddr, 1169 policy->family, 1170 policy->selector.prefixlen_s, 1171 dir); 1172 write_seqcount_end(&bin->count); 1173 if (!n) 1174 return NULL; 1175 1176 return &n->hhead; 1177 } 1178 1179 /* daddr is fixed */ 1180 write_seqcount_begin(&bin->count); 1181 n = xfrm_policy_inexact_insert_node(net, 1182 &bin->root_d, 1183 &policy->selector.daddr, 1184 policy->family, 1185 policy->selector.prefixlen_d, dir); 1186 write_seqcount_end(&bin->count); 1187 if (!n) 1188 return NULL; 1189 1190 /* saddr is wildcard */ 1191 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1192 policy->family, 1193 policy->selector.prefixlen_s)) 1194 return &n->hhead; 1195 1196 write_seqcount_begin(&bin->count); 1197 n = xfrm_policy_inexact_insert_node(net, 1198 &n->root, 1199 &policy->selector.saddr, 1200 policy->family, 1201 policy->selector.prefixlen_s, dir); 1202 write_seqcount_end(&bin->count); 1203 if (!n) 1204 return NULL; 1205 1206 return &n->hhead; 1207 } 1208 1209 static struct xfrm_policy * 1210 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1211 { 1212 struct xfrm_pol_inexact_bin *bin; 1213 struct xfrm_policy *delpol; 1214 struct hlist_head *chain; 1215 struct net *net; 1216 1217 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1218 if (!bin) 1219 return ERR_PTR(-ENOMEM); 1220 1221 net = xp_net(policy); 1222 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1223 1224 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1225 if (!chain) { 1226 __xfrm_policy_inexact_prune_bin(bin, false); 1227 return ERR_PTR(-ENOMEM); 1228 } 1229 1230 delpol = xfrm_policy_insert_list(chain, policy, excl); 1231 if (delpol && excl) { 1232 __xfrm_policy_inexact_prune_bin(bin, false); 1233 return ERR_PTR(-EEXIST); 1234 } 1235 1236 chain = &net->xfrm.policy_inexact[dir]; 1237 xfrm_policy_insert_inexact_list(chain, policy); 1238 1239 if (delpol) 1240 __xfrm_policy_inexact_prune_bin(bin, false); 1241 1242 return delpol; 1243 } 1244 1245 static void xfrm_hash_rebuild(struct work_struct *work) 1246 { 1247 struct net *net = container_of(work, struct net, 1248 xfrm.policy_hthresh.work); 1249 unsigned int hmask; 1250 struct xfrm_policy *pol; 1251 struct xfrm_policy *policy; 1252 struct hlist_head *chain; 1253 struct hlist_head *odst; 1254 struct hlist_node *newpos; 1255 int i; 1256 int dir; 1257 unsigned seq; 1258 u8 lbits4, rbits4, lbits6, rbits6; 1259 1260 mutex_lock(&hash_resize_mutex); 1261 1262 /* read selector prefixlen thresholds */ 1263 do { 1264 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1265 1266 lbits4 = net->xfrm.policy_hthresh.lbits4; 1267 rbits4 = net->xfrm.policy_hthresh.rbits4; 1268 lbits6 = net->xfrm.policy_hthresh.lbits6; 1269 rbits6 = net->xfrm.policy_hthresh.rbits6; 1270 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1271 1272 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1273 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 1274 1275 /* make sure that we can insert the indirect policies again before 1276 * we start with destructive action. 1277 */ 1278 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1279 struct xfrm_pol_inexact_bin *bin; 1280 u8 dbits, sbits; 1281 1282 if (policy->walk.dead) 1283 continue; 1284 1285 dir = xfrm_policy_id2dir(policy->index); 1286 if (dir >= XFRM_POLICY_MAX) 1287 continue; 1288 1289 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1290 if (policy->family == AF_INET) { 1291 dbits = rbits4; 1292 sbits = lbits4; 1293 } else { 1294 dbits = rbits6; 1295 sbits = lbits6; 1296 } 1297 } else { 1298 if (policy->family == AF_INET) { 1299 dbits = lbits4; 1300 sbits = rbits4; 1301 } else { 1302 dbits = lbits6; 1303 sbits = rbits6; 1304 } 1305 } 1306 1307 if (policy->selector.prefixlen_d < dbits || 1308 policy->selector.prefixlen_s < sbits) 1309 continue; 1310 1311 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1312 if (!bin) 1313 goto out_unlock; 1314 1315 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1316 goto out_unlock; 1317 } 1318 1319 /* reset the bydst and inexact table in all directions */ 1320 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1321 struct hlist_node *n; 1322 1323 hlist_for_each_entry_safe(policy, n, 1324 &net->xfrm.policy_inexact[dir], 1325 bydst_inexact_list) { 1326 hlist_del_rcu(&policy->bydst); 1327 hlist_del_init(&policy->bydst_inexact_list); 1328 } 1329 1330 hmask = net->xfrm.policy_bydst[dir].hmask; 1331 odst = net->xfrm.policy_bydst[dir].table; 1332 for (i = hmask; i >= 0; i--) { 1333 hlist_for_each_entry_safe(policy, n, odst + i, bydst) 1334 hlist_del_rcu(&policy->bydst); 1335 } 1336 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1337 /* dir out => dst = remote, src = local */ 1338 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1339 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1340 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1341 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1342 } else { 1343 /* dir in/fwd => dst = local, src = remote */ 1344 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1345 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1346 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1347 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1348 } 1349 } 1350 1351 /* re-insert all policies by order of creation */ 1352 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1353 if (policy->walk.dead) 1354 continue; 1355 dir = xfrm_policy_id2dir(policy->index); 1356 if (dir >= XFRM_POLICY_MAX) { 1357 /* skip socket policies */ 1358 continue; 1359 } 1360 newpos = NULL; 1361 chain = policy_hash_bysel(net, &policy->selector, 1362 policy->family, dir); 1363 1364 if (!chain) { 1365 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1366 1367 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1368 continue; 1369 } 1370 1371 hlist_for_each_entry(pol, chain, bydst) { 1372 if (policy->priority >= pol->priority) 1373 newpos = &pol->bydst; 1374 else 1375 break; 1376 } 1377 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1378 hlist_add_behind_rcu(&policy->bydst, newpos); 1379 else 1380 hlist_add_head_rcu(&policy->bydst, chain); 1381 } 1382 1383 out_unlock: 1384 __xfrm_policy_inexact_flush(net); 1385 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 1386 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1387 1388 mutex_unlock(&hash_resize_mutex); 1389 } 1390 1391 void xfrm_policy_hash_rebuild(struct net *net) 1392 { 1393 schedule_work(&net->xfrm.policy_hthresh.work); 1394 } 1395 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1396 1397 /* Generate new index... KAME seems to generate them ordered by cost 1398 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1399 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1400 { 1401 for (;;) { 1402 struct hlist_head *list; 1403 struct xfrm_policy *p; 1404 u32 idx; 1405 int found; 1406 1407 if (!index) { 1408 idx = (net->xfrm.idx_generator | dir); 1409 net->xfrm.idx_generator += 8; 1410 } else { 1411 idx = index; 1412 index = 0; 1413 } 1414 1415 if (idx == 0) 1416 idx = 8; 1417 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1418 found = 0; 1419 hlist_for_each_entry(p, list, byidx) { 1420 if (p->index == idx) { 1421 found = 1; 1422 break; 1423 } 1424 } 1425 if (!found) 1426 return idx; 1427 } 1428 } 1429 1430 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1431 { 1432 u32 *p1 = (u32 *) s1; 1433 u32 *p2 = (u32 *) s2; 1434 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1435 int i; 1436 1437 for (i = 0; i < len; i++) { 1438 if (p1[i] != p2[i]) 1439 return 1; 1440 } 1441 1442 return 0; 1443 } 1444 1445 static void xfrm_policy_requeue(struct xfrm_policy *old, 1446 struct xfrm_policy *new) 1447 { 1448 struct xfrm_policy_queue *pq = &old->polq; 1449 struct sk_buff_head list; 1450 1451 if (skb_queue_empty(&pq->hold_queue)) 1452 return; 1453 1454 __skb_queue_head_init(&list); 1455 1456 spin_lock_bh(&pq->hold_queue.lock); 1457 skb_queue_splice_init(&pq->hold_queue, &list); 1458 if (del_timer(&pq->hold_timer)) 1459 xfrm_pol_put(old); 1460 spin_unlock_bh(&pq->hold_queue.lock); 1461 1462 pq = &new->polq; 1463 1464 spin_lock_bh(&pq->hold_queue.lock); 1465 skb_queue_splice(&list, &pq->hold_queue); 1466 pq->timeout = XFRM_QUEUE_TMO_MIN; 1467 if (!mod_timer(&pq->hold_timer, jiffies)) 1468 xfrm_pol_hold(new); 1469 spin_unlock_bh(&pq->hold_queue.lock); 1470 } 1471 1472 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark, 1473 struct xfrm_policy *pol) 1474 { 1475 return mark->v == pol->mark.v && mark->m == pol->mark.m; 1476 } 1477 1478 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1479 { 1480 const struct xfrm_pol_inexact_key *k = data; 1481 u32 a = k->type << 24 | k->dir << 16 | k->family; 1482 1483 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1484 seed); 1485 } 1486 1487 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1488 { 1489 const struct xfrm_pol_inexact_bin *b = data; 1490 1491 return xfrm_pol_bin_key(&b->k, 0, seed); 1492 } 1493 1494 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1495 const void *ptr) 1496 { 1497 const struct xfrm_pol_inexact_key *key = arg->key; 1498 const struct xfrm_pol_inexact_bin *b = ptr; 1499 int ret; 1500 1501 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1502 return -1; 1503 1504 ret = b->k.dir ^ key->dir; 1505 if (ret) 1506 return ret; 1507 1508 ret = b->k.type ^ key->type; 1509 if (ret) 1510 return ret; 1511 1512 ret = b->k.family ^ key->family; 1513 if (ret) 1514 return ret; 1515 1516 return b->k.if_id ^ key->if_id; 1517 } 1518 1519 static const struct rhashtable_params xfrm_pol_inexact_params = { 1520 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1521 .hashfn = xfrm_pol_bin_key, 1522 .obj_hashfn = xfrm_pol_bin_obj, 1523 .obj_cmpfn = xfrm_pol_bin_cmp, 1524 .automatic_shrinking = true, 1525 }; 1526 1527 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1528 struct xfrm_policy *policy) 1529 { 1530 struct xfrm_policy *pol, *delpol = NULL; 1531 struct hlist_node *newpos = NULL; 1532 int i = 0; 1533 1534 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1535 if (pol->type == policy->type && 1536 pol->if_id == policy->if_id && 1537 !selector_cmp(&pol->selector, &policy->selector) && 1538 xfrm_policy_mark_match(&policy->mark, pol) && 1539 xfrm_sec_ctx_match(pol->security, policy->security) && 1540 !WARN_ON(delpol)) { 1541 delpol = pol; 1542 if (policy->priority > pol->priority) 1543 continue; 1544 } else if (policy->priority >= pol->priority) { 1545 newpos = &pol->bydst_inexact_list; 1546 continue; 1547 } 1548 if (delpol) 1549 break; 1550 } 1551 1552 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1553 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1554 else 1555 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1556 1557 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1558 pol->pos = i; 1559 i++; 1560 } 1561 } 1562 1563 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1564 struct xfrm_policy *policy, 1565 bool excl) 1566 { 1567 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1568 1569 hlist_for_each_entry(pol, chain, bydst) { 1570 if (pol->type == policy->type && 1571 pol->if_id == policy->if_id && 1572 !selector_cmp(&pol->selector, &policy->selector) && 1573 xfrm_policy_mark_match(&policy->mark, pol) && 1574 xfrm_sec_ctx_match(pol->security, policy->security) && 1575 !WARN_ON(delpol)) { 1576 if (excl) 1577 return ERR_PTR(-EEXIST); 1578 delpol = pol; 1579 if (policy->priority > pol->priority) 1580 continue; 1581 } else if (policy->priority >= pol->priority) { 1582 newpos = pol; 1583 continue; 1584 } 1585 if (delpol) 1586 break; 1587 } 1588 1589 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1590 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1591 else 1592 /* Packet offload policies enter to the head 1593 * to speed-up lookups. 1594 */ 1595 hlist_add_head_rcu(&policy->bydst, chain); 1596 1597 return delpol; 1598 } 1599 1600 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1601 { 1602 struct net *net = xp_net(policy); 1603 struct xfrm_policy *delpol; 1604 struct hlist_head *chain; 1605 1606 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1607 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1608 if (chain) 1609 delpol = xfrm_policy_insert_list(chain, policy, excl); 1610 else 1611 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1612 1613 if (IS_ERR(delpol)) { 1614 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1615 return PTR_ERR(delpol); 1616 } 1617 1618 __xfrm_policy_link(policy, dir); 1619 1620 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1621 if (policy->family == AF_INET) 1622 rt_genid_bump_ipv4(net); 1623 else 1624 rt_genid_bump_ipv6(net); 1625 1626 if (delpol) { 1627 xfrm_policy_requeue(delpol, policy); 1628 __xfrm_policy_unlink(delpol, dir); 1629 } 1630 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1631 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1632 policy->curlft.add_time = ktime_get_real_seconds(); 1633 policy->curlft.use_time = 0; 1634 if (!mod_timer(&policy->timer, jiffies + HZ)) 1635 xfrm_pol_hold(policy); 1636 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1637 1638 if (delpol) 1639 xfrm_policy_kill(delpol); 1640 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1641 schedule_work(&net->xfrm.policy_hash_work); 1642 1643 return 0; 1644 } 1645 EXPORT_SYMBOL(xfrm_policy_insert); 1646 1647 static struct xfrm_policy * 1648 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark, 1649 u32 if_id, u8 type, int dir, struct xfrm_selector *sel, 1650 struct xfrm_sec_ctx *ctx) 1651 { 1652 struct xfrm_policy *pol; 1653 1654 if (!chain) 1655 return NULL; 1656 1657 hlist_for_each_entry(pol, chain, bydst) { 1658 if (pol->type == type && 1659 pol->if_id == if_id && 1660 xfrm_policy_mark_match(mark, pol) && 1661 !selector_cmp(sel, &pol->selector) && 1662 xfrm_sec_ctx_match(ctx, pol->security)) 1663 return pol; 1664 } 1665 1666 return NULL; 1667 } 1668 1669 struct xfrm_policy * 1670 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1671 u8 type, int dir, struct xfrm_selector *sel, 1672 struct xfrm_sec_ctx *ctx, int delete, int *err) 1673 { 1674 struct xfrm_pol_inexact_bin *bin = NULL; 1675 struct xfrm_policy *pol, *ret = NULL; 1676 struct hlist_head *chain; 1677 1678 *err = 0; 1679 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1680 chain = policy_hash_bysel(net, sel, sel->family, dir); 1681 if (!chain) { 1682 struct xfrm_pol_inexact_candidates cand; 1683 int i; 1684 1685 bin = xfrm_policy_inexact_lookup(net, type, 1686 sel->family, dir, if_id); 1687 if (!bin) { 1688 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1689 return NULL; 1690 } 1691 1692 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1693 &sel->saddr, 1694 &sel->daddr)) { 1695 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1696 return NULL; 1697 } 1698 1699 pol = NULL; 1700 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1701 struct xfrm_policy *tmp; 1702 1703 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1704 if_id, type, dir, 1705 sel, ctx); 1706 if (!tmp) 1707 continue; 1708 1709 if (!pol || tmp->pos < pol->pos) 1710 pol = tmp; 1711 } 1712 } else { 1713 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1714 sel, ctx); 1715 } 1716 1717 if (pol) { 1718 xfrm_pol_hold(pol); 1719 if (delete) { 1720 *err = security_xfrm_policy_delete(pol->security); 1721 if (*err) { 1722 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1723 return pol; 1724 } 1725 __xfrm_policy_unlink(pol, dir); 1726 } 1727 ret = pol; 1728 } 1729 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1730 1731 if (ret && delete) 1732 xfrm_policy_kill(ret); 1733 if (bin && delete) 1734 xfrm_policy_inexact_prune_bin(bin); 1735 return ret; 1736 } 1737 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1738 1739 struct xfrm_policy * 1740 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1741 u8 type, int dir, u32 id, int delete, int *err) 1742 { 1743 struct xfrm_policy *pol, *ret; 1744 struct hlist_head *chain; 1745 1746 *err = -ENOENT; 1747 if (xfrm_policy_id2dir(id) != dir) 1748 return NULL; 1749 1750 *err = 0; 1751 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1752 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1753 ret = NULL; 1754 hlist_for_each_entry(pol, chain, byidx) { 1755 if (pol->type == type && pol->index == id && 1756 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) { 1757 xfrm_pol_hold(pol); 1758 if (delete) { 1759 *err = security_xfrm_policy_delete( 1760 pol->security); 1761 if (*err) { 1762 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1763 return pol; 1764 } 1765 __xfrm_policy_unlink(pol, dir); 1766 } 1767 ret = pol; 1768 break; 1769 } 1770 } 1771 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1772 1773 if (ret && delete) 1774 xfrm_policy_kill(ret); 1775 return ret; 1776 } 1777 EXPORT_SYMBOL(xfrm_policy_byid); 1778 1779 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1780 static inline int 1781 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1782 { 1783 struct xfrm_policy *pol; 1784 int err = 0; 1785 1786 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1787 if (pol->walk.dead || 1788 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1789 pol->type != type) 1790 continue; 1791 1792 err = security_xfrm_policy_delete(pol->security); 1793 if (err) { 1794 xfrm_audit_policy_delete(pol, 0, task_valid); 1795 return err; 1796 } 1797 } 1798 return err; 1799 } 1800 1801 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, 1802 struct net_device *dev, 1803 bool task_valid) 1804 { 1805 struct xfrm_policy *pol; 1806 int err = 0; 1807 1808 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1809 if (pol->walk.dead || 1810 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1811 pol->xdo.dev != dev) 1812 continue; 1813 1814 err = security_xfrm_policy_delete(pol->security); 1815 if (err) { 1816 xfrm_audit_policy_delete(pol, 0, task_valid); 1817 return err; 1818 } 1819 } 1820 return err; 1821 } 1822 #else 1823 static inline int 1824 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1825 { 1826 return 0; 1827 } 1828 1829 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, 1830 struct net_device *dev, 1831 bool task_valid) 1832 { 1833 return 0; 1834 } 1835 #endif 1836 1837 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1838 { 1839 int dir, err = 0, cnt = 0; 1840 struct xfrm_policy *pol; 1841 1842 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1843 1844 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1845 if (err) 1846 goto out; 1847 1848 again: 1849 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1850 if (pol->walk.dead) 1851 continue; 1852 1853 dir = xfrm_policy_id2dir(pol->index); 1854 if (dir >= XFRM_POLICY_MAX || 1855 pol->type != type) 1856 continue; 1857 1858 __xfrm_policy_unlink(pol, dir); 1859 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1860 cnt++; 1861 xfrm_audit_policy_delete(pol, 1, task_valid); 1862 xfrm_policy_kill(pol); 1863 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1864 goto again; 1865 } 1866 if (cnt) 1867 __xfrm_policy_inexact_flush(net); 1868 else 1869 err = -ESRCH; 1870 out: 1871 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1872 return err; 1873 } 1874 EXPORT_SYMBOL(xfrm_policy_flush); 1875 1876 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev, 1877 bool task_valid) 1878 { 1879 int dir, err = 0, cnt = 0; 1880 struct xfrm_policy *pol; 1881 1882 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1883 1884 err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid); 1885 if (err) 1886 goto out; 1887 1888 again: 1889 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1890 if (pol->walk.dead) 1891 continue; 1892 1893 dir = xfrm_policy_id2dir(pol->index); 1894 if (dir >= XFRM_POLICY_MAX || 1895 pol->xdo.dev != dev) 1896 continue; 1897 1898 __xfrm_policy_unlink(pol, dir); 1899 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1900 cnt++; 1901 xfrm_audit_policy_delete(pol, 1, task_valid); 1902 xfrm_policy_kill(pol); 1903 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1904 goto again; 1905 } 1906 if (cnt) 1907 __xfrm_policy_inexact_flush(net); 1908 else 1909 err = -ESRCH; 1910 out: 1911 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1912 return err; 1913 } 1914 EXPORT_SYMBOL(xfrm_dev_policy_flush); 1915 1916 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1917 int (*func)(struct xfrm_policy *, int, int, void*), 1918 void *data) 1919 { 1920 struct xfrm_policy *pol; 1921 struct xfrm_policy_walk_entry *x; 1922 int error = 0; 1923 1924 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1925 walk->type != XFRM_POLICY_TYPE_ANY) 1926 return -EINVAL; 1927 1928 if (list_empty(&walk->walk.all) && walk->seq != 0) 1929 return 0; 1930 1931 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1932 if (list_empty(&walk->walk.all)) 1933 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1934 else 1935 x = list_first_entry(&walk->walk.all, 1936 struct xfrm_policy_walk_entry, all); 1937 1938 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1939 if (x->dead) 1940 continue; 1941 pol = container_of(x, struct xfrm_policy, walk); 1942 if (walk->type != XFRM_POLICY_TYPE_ANY && 1943 walk->type != pol->type) 1944 continue; 1945 error = func(pol, xfrm_policy_id2dir(pol->index), 1946 walk->seq, data); 1947 if (error) { 1948 list_move_tail(&walk->walk.all, &x->all); 1949 goto out; 1950 } 1951 walk->seq++; 1952 } 1953 if (walk->seq == 0) { 1954 error = -ENOENT; 1955 goto out; 1956 } 1957 list_del_init(&walk->walk.all); 1958 out: 1959 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1960 return error; 1961 } 1962 EXPORT_SYMBOL(xfrm_policy_walk); 1963 1964 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1965 { 1966 INIT_LIST_HEAD(&walk->walk.all); 1967 walk->walk.dead = 1; 1968 walk->type = type; 1969 walk->seq = 0; 1970 } 1971 EXPORT_SYMBOL(xfrm_policy_walk_init); 1972 1973 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1974 { 1975 if (list_empty(&walk->walk.all)) 1976 return; 1977 1978 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1979 list_del(&walk->walk.all); 1980 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1981 } 1982 EXPORT_SYMBOL(xfrm_policy_walk_done); 1983 1984 /* 1985 * Find policy to apply to this flow. 1986 * 1987 * Returns 0 if policy found, else an -errno. 1988 */ 1989 static int xfrm_policy_match(const struct xfrm_policy *pol, 1990 const struct flowi *fl, 1991 u8 type, u16 family, u32 if_id) 1992 { 1993 const struct xfrm_selector *sel = &pol->selector; 1994 int ret = -ESRCH; 1995 bool match; 1996 1997 if (pol->family != family || 1998 pol->if_id != if_id || 1999 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 2000 pol->type != type) 2001 return ret; 2002 2003 match = xfrm_selector_match(sel, fl, family); 2004 if (match) 2005 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid); 2006 return ret; 2007 } 2008 2009 static struct xfrm_pol_inexact_node * 2010 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 2011 seqcount_spinlock_t *count, 2012 const xfrm_address_t *addr, u16 family) 2013 { 2014 const struct rb_node *parent; 2015 int seq; 2016 2017 again: 2018 seq = read_seqcount_begin(count); 2019 2020 parent = rcu_dereference_raw(r->rb_node); 2021 while (parent) { 2022 struct xfrm_pol_inexact_node *node; 2023 int delta; 2024 2025 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 2026 2027 delta = xfrm_policy_addr_delta(addr, &node->addr, 2028 node->prefixlen, family); 2029 if (delta < 0) { 2030 parent = rcu_dereference_raw(parent->rb_left); 2031 continue; 2032 } else if (delta > 0) { 2033 parent = rcu_dereference_raw(parent->rb_right); 2034 continue; 2035 } 2036 2037 return node; 2038 } 2039 2040 if (read_seqcount_retry(count, seq)) 2041 goto again; 2042 2043 return NULL; 2044 } 2045 2046 static bool 2047 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 2048 struct xfrm_pol_inexact_bin *b, 2049 const xfrm_address_t *saddr, 2050 const xfrm_address_t *daddr) 2051 { 2052 struct xfrm_pol_inexact_node *n; 2053 u16 family; 2054 2055 if (!b) 2056 return false; 2057 2058 family = b->k.family; 2059 memset(cand, 0, sizeof(*cand)); 2060 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 2061 2062 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 2063 family); 2064 if (n) { 2065 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 2066 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 2067 family); 2068 if (n) 2069 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 2070 } 2071 2072 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 2073 family); 2074 if (n) 2075 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 2076 2077 return true; 2078 } 2079 2080 static struct xfrm_pol_inexact_bin * 2081 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 2082 u8 dir, u32 if_id) 2083 { 2084 struct xfrm_pol_inexact_key k = { 2085 .family = family, 2086 .type = type, 2087 .dir = dir, 2088 .if_id = if_id, 2089 }; 2090 2091 write_pnet(&k.net, net); 2092 2093 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 2094 xfrm_pol_inexact_params); 2095 } 2096 2097 static struct xfrm_pol_inexact_bin * 2098 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 2099 u8 dir, u32 if_id) 2100 { 2101 struct xfrm_pol_inexact_bin *bin; 2102 2103 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2104 2105 rcu_read_lock(); 2106 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2107 rcu_read_unlock(); 2108 2109 return bin; 2110 } 2111 2112 static struct xfrm_policy * 2113 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2114 struct xfrm_policy *prefer, 2115 const struct flowi *fl, 2116 u8 type, u16 family, u32 if_id) 2117 { 2118 u32 priority = prefer ? prefer->priority : ~0u; 2119 struct xfrm_policy *pol; 2120 2121 if (!chain) 2122 return NULL; 2123 2124 hlist_for_each_entry_rcu(pol, chain, bydst) { 2125 int err; 2126 2127 if (pol->priority > priority) 2128 break; 2129 2130 err = xfrm_policy_match(pol, fl, type, family, if_id); 2131 if (err) { 2132 if (err != -ESRCH) 2133 return ERR_PTR(err); 2134 2135 continue; 2136 } 2137 2138 if (prefer) { 2139 /* matches. Is it older than *prefer? */ 2140 if (pol->priority == priority && 2141 prefer->pos < pol->pos) 2142 return prefer; 2143 } 2144 2145 return pol; 2146 } 2147 2148 return NULL; 2149 } 2150 2151 static struct xfrm_policy * 2152 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2153 struct xfrm_policy *prefer, 2154 const struct flowi *fl, 2155 u8 type, u16 family, u32 if_id) 2156 { 2157 struct xfrm_policy *tmp; 2158 int i; 2159 2160 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2161 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2162 prefer, 2163 fl, type, family, if_id); 2164 if (!tmp) 2165 continue; 2166 2167 if (IS_ERR(tmp)) 2168 return tmp; 2169 prefer = tmp; 2170 } 2171 2172 return prefer; 2173 } 2174 2175 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2176 const struct flowi *fl, 2177 u16 family, u8 dir, 2178 u32 if_id) 2179 { 2180 struct xfrm_pol_inexact_candidates cand; 2181 const xfrm_address_t *daddr, *saddr; 2182 struct xfrm_pol_inexact_bin *bin; 2183 struct xfrm_policy *pol, *ret; 2184 struct hlist_head *chain; 2185 unsigned int sequence; 2186 int err; 2187 2188 daddr = xfrm_flowi_daddr(fl, family); 2189 saddr = xfrm_flowi_saddr(fl, family); 2190 if (unlikely(!daddr || !saddr)) 2191 return NULL; 2192 2193 rcu_read_lock(); 2194 retry: 2195 do { 2196 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 2197 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2198 } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)); 2199 2200 ret = NULL; 2201 hlist_for_each_entry_rcu(pol, chain, bydst) { 2202 err = xfrm_policy_match(pol, fl, type, family, if_id); 2203 if (err) { 2204 if (err == -ESRCH) 2205 continue; 2206 else { 2207 ret = ERR_PTR(err); 2208 goto fail; 2209 } 2210 } else { 2211 ret = pol; 2212 break; 2213 } 2214 } 2215 if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET) 2216 goto skip_inexact; 2217 2218 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2219 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2220 daddr)) 2221 goto skip_inexact; 2222 2223 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2224 family, if_id); 2225 if (pol) { 2226 ret = pol; 2227 if (IS_ERR(pol)) 2228 goto fail; 2229 } 2230 2231 skip_inexact: 2232 if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)) 2233 goto retry; 2234 2235 if (ret && !xfrm_pol_hold_rcu(ret)) 2236 goto retry; 2237 fail: 2238 rcu_read_unlock(); 2239 2240 return ret; 2241 } 2242 2243 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2244 const struct flowi *fl, 2245 u16 family, u8 dir, u32 if_id) 2246 { 2247 #ifdef CONFIG_XFRM_SUB_POLICY 2248 struct xfrm_policy *pol; 2249 2250 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2251 dir, if_id); 2252 if (pol != NULL) 2253 return pol; 2254 #endif 2255 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2256 dir, if_id); 2257 } 2258 2259 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2260 const struct flowi *fl, 2261 u16 family, u32 if_id) 2262 { 2263 struct xfrm_policy *pol; 2264 2265 rcu_read_lock(); 2266 again: 2267 pol = rcu_dereference(sk->sk_policy[dir]); 2268 if (pol != NULL) { 2269 bool match; 2270 int err = 0; 2271 2272 if (pol->family != family) { 2273 pol = NULL; 2274 goto out; 2275 } 2276 2277 match = xfrm_selector_match(&pol->selector, fl, family); 2278 if (match) { 2279 if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v || 2280 pol->if_id != if_id) { 2281 pol = NULL; 2282 goto out; 2283 } 2284 err = security_xfrm_policy_lookup(pol->security, 2285 fl->flowi_secid); 2286 if (!err) { 2287 if (!xfrm_pol_hold_rcu(pol)) 2288 goto again; 2289 } else if (err == -ESRCH) { 2290 pol = NULL; 2291 } else { 2292 pol = ERR_PTR(err); 2293 } 2294 } else 2295 pol = NULL; 2296 } 2297 out: 2298 rcu_read_unlock(); 2299 return pol; 2300 } 2301 2302 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2303 { 2304 struct net *net = xp_net(pol); 2305 2306 list_add(&pol->walk.all, &net->xfrm.policy_all); 2307 net->xfrm.policy_count[dir]++; 2308 xfrm_pol_hold(pol); 2309 } 2310 2311 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2312 int dir) 2313 { 2314 struct net *net = xp_net(pol); 2315 2316 if (list_empty(&pol->walk.all)) 2317 return NULL; 2318 2319 /* Socket policies are not hashed. */ 2320 if (!hlist_unhashed(&pol->bydst)) { 2321 hlist_del_rcu(&pol->bydst); 2322 hlist_del_init(&pol->bydst_inexact_list); 2323 hlist_del(&pol->byidx); 2324 } 2325 2326 list_del_init(&pol->walk.all); 2327 net->xfrm.policy_count[dir]--; 2328 2329 return pol; 2330 } 2331 2332 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2333 { 2334 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2335 } 2336 2337 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2338 { 2339 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2340 } 2341 2342 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2343 { 2344 struct net *net = xp_net(pol); 2345 2346 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2347 pol = __xfrm_policy_unlink(pol, dir); 2348 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2349 if (pol) { 2350 xfrm_policy_kill(pol); 2351 return 0; 2352 } 2353 return -ENOENT; 2354 } 2355 EXPORT_SYMBOL(xfrm_policy_delete); 2356 2357 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2358 { 2359 struct net *net = sock_net(sk); 2360 struct xfrm_policy *old_pol; 2361 2362 #ifdef CONFIG_XFRM_SUB_POLICY 2363 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2364 return -EINVAL; 2365 #endif 2366 2367 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2368 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2369 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2370 if (pol) { 2371 pol->curlft.add_time = ktime_get_real_seconds(); 2372 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2373 xfrm_sk_policy_link(pol, dir); 2374 } 2375 rcu_assign_pointer(sk->sk_policy[dir], pol); 2376 if (old_pol) { 2377 if (pol) 2378 xfrm_policy_requeue(old_pol, pol); 2379 2380 /* Unlinking succeeds always. This is the only function 2381 * allowed to delete or replace socket policy. 2382 */ 2383 xfrm_sk_policy_unlink(old_pol, dir); 2384 } 2385 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2386 2387 if (old_pol) { 2388 xfrm_policy_kill(old_pol); 2389 } 2390 return 0; 2391 } 2392 2393 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2394 { 2395 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2396 struct net *net = xp_net(old); 2397 2398 if (newp) { 2399 newp->selector = old->selector; 2400 if (security_xfrm_policy_clone(old->security, 2401 &newp->security)) { 2402 kfree(newp); 2403 return NULL; /* ENOMEM */ 2404 } 2405 newp->lft = old->lft; 2406 newp->curlft = old->curlft; 2407 newp->mark = old->mark; 2408 newp->if_id = old->if_id; 2409 newp->action = old->action; 2410 newp->flags = old->flags; 2411 newp->xfrm_nr = old->xfrm_nr; 2412 newp->index = old->index; 2413 newp->type = old->type; 2414 newp->family = old->family; 2415 memcpy(newp->xfrm_vec, old->xfrm_vec, 2416 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2417 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2418 xfrm_sk_policy_link(newp, dir); 2419 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2420 xfrm_pol_put(newp); 2421 } 2422 return newp; 2423 } 2424 2425 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2426 { 2427 const struct xfrm_policy *p; 2428 struct xfrm_policy *np; 2429 int i, ret = 0; 2430 2431 rcu_read_lock(); 2432 for (i = 0; i < 2; i++) { 2433 p = rcu_dereference(osk->sk_policy[i]); 2434 if (p) { 2435 np = clone_policy(p, i); 2436 if (unlikely(!np)) { 2437 ret = -ENOMEM; 2438 break; 2439 } 2440 rcu_assign_pointer(sk->sk_policy[i], np); 2441 } 2442 } 2443 rcu_read_unlock(); 2444 return ret; 2445 } 2446 2447 static int 2448 xfrm_get_saddr(unsigned short family, xfrm_address_t *saddr, 2449 const struct xfrm_dst_lookup_params *params) 2450 { 2451 int err; 2452 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2453 2454 if (unlikely(afinfo == NULL)) 2455 return -EINVAL; 2456 err = afinfo->get_saddr(saddr, params); 2457 rcu_read_unlock(); 2458 return err; 2459 } 2460 2461 /* Resolve list of templates for the flow, given policy. */ 2462 2463 static int 2464 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2465 struct xfrm_state **xfrm, unsigned short family) 2466 { 2467 struct net *net = xp_net(policy); 2468 int nx; 2469 int i, error; 2470 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2471 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2472 xfrm_address_t tmp; 2473 2474 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2475 struct xfrm_state *x; 2476 xfrm_address_t *remote = daddr; 2477 xfrm_address_t *local = saddr; 2478 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2479 2480 if (tmpl->mode == XFRM_MODE_TUNNEL || 2481 tmpl->mode == XFRM_MODE_BEET) { 2482 remote = &tmpl->id.daddr; 2483 local = &tmpl->saddr; 2484 if (xfrm_addr_any(local, tmpl->encap_family)) { 2485 struct xfrm_dst_lookup_params params; 2486 2487 memset(¶ms, 0, sizeof(params)); 2488 params.net = net; 2489 params.oif = fl->flowi_oif; 2490 params.daddr = remote; 2491 error = xfrm_get_saddr(tmpl->encap_family, &tmp, 2492 ¶ms); 2493 if (error) 2494 goto fail; 2495 local = &tmp; 2496 } 2497 } 2498 2499 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2500 family, policy->if_id); 2501 2502 if (x && x->km.state == XFRM_STATE_VALID) { 2503 xfrm[nx++] = x; 2504 daddr = remote; 2505 saddr = local; 2506 continue; 2507 } 2508 if (x) { 2509 error = (x->km.state == XFRM_STATE_ERROR ? 2510 -EINVAL : -EAGAIN); 2511 xfrm_state_put(x); 2512 } else if (error == -ESRCH) { 2513 error = -EAGAIN; 2514 } 2515 2516 if (!tmpl->optional) 2517 goto fail; 2518 } 2519 return nx; 2520 2521 fail: 2522 for (nx--; nx >= 0; nx--) 2523 xfrm_state_put(xfrm[nx]); 2524 return error; 2525 } 2526 2527 static int 2528 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2529 struct xfrm_state **xfrm, unsigned short family) 2530 { 2531 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2532 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2533 int cnx = 0; 2534 int error; 2535 int ret; 2536 int i; 2537 2538 for (i = 0; i < npols; i++) { 2539 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2540 error = -ENOBUFS; 2541 goto fail; 2542 } 2543 2544 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2545 if (ret < 0) { 2546 error = ret; 2547 goto fail; 2548 } else 2549 cnx += ret; 2550 } 2551 2552 /* found states are sorted for outbound processing */ 2553 if (npols > 1) 2554 xfrm_state_sort(xfrm, tpp, cnx, family); 2555 2556 return cnx; 2557 2558 fail: 2559 for (cnx--; cnx >= 0; cnx--) 2560 xfrm_state_put(tpp[cnx]); 2561 return error; 2562 2563 } 2564 2565 static int xfrm_get_tos(const struct flowi *fl, int family) 2566 { 2567 if (family == AF_INET) 2568 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2569 2570 return 0; 2571 } 2572 2573 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2574 { 2575 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2576 struct dst_ops *dst_ops; 2577 struct xfrm_dst *xdst; 2578 2579 if (!afinfo) 2580 return ERR_PTR(-EINVAL); 2581 2582 switch (family) { 2583 case AF_INET: 2584 dst_ops = &net->xfrm.xfrm4_dst_ops; 2585 break; 2586 #if IS_ENABLED(CONFIG_IPV6) 2587 case AF_INET6: 2588 dst_ops = &net->xfrm.xfrm6_dst_ops; 2589 break; 2590 #endif 2591 default: 2592 BUG(); 2593 } 2594 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2595 2596 if (likely(xdst)) { 2597 memset_after(xdst, 0, u.dst); 2598 } else 2599 xdst = ERR_PTR(-ENOBUFS); 2600 2601 rcu_read_unlock(); 2602 2603 return xdst; 2604 } 2605 2606 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2607 int nfheader_len) 2608 { 2609 if (dst->ops->family == AF_INET6) { 2610 path->path_cookie = rt6_get_cookie(dst_rt6_info(dst)); 2611 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2612 } 2613 } 2614 2615 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2616 const struct flowi *fl) 2617 { 2618 const struct xfrm_policy_afinfo *afinfo = 2619 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2620 int err; 2621 2622 if (!afinfo) 2623 return -EINVAL; 2624 2625 err = afinfo->fill_dst(xdst, dev, fl); 2626 2627 rcu_read_unlock(); 2628 2629 return err; 2630 } 2631 2632 2633 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2634 * all the metrics... Shortly, bundle a bundle. 2635 */ 2636 2637 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2638 struct xfrm_state **xfrm, 2639 struct xfrm_dst **bundle, 2640 int nx, 2641 const struct flowi *fl, 2642 struct dst_entry *dst) 2643 { 2644 const struct xfrm_state_afinfo *afinfo; 2645 const struct xfrm_mode *inner_mode; 2646 struct net *net = xp_net(policy); 2647 unsigned long now = jiffies; 2648 struct net_device *dev; 2649 struct xfrm_dst *xdst_prev = NULL; 2650 struct xfrm_dst *xdst0 = NULL; 2651 int i = 0; 2652 int err; 2653 int header_len = 0; 2654 int nfheader_len = 0; 2655 int trailer_len = 0; 2656 int tos; 2657 int family = policy->selector.family; 2658 xfrm_address_t saddr, daddr; 2659 2660 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2661 2662 tos = xfrm_get_tos(fl, family); 2663 2664 dst_hold(dst); 2665 2666 for (; i < nx; i++) { 2667 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2668 struct dst_entry *dst1 = &xdst->u.dst; 2669 2670 err = PTR_ERR(xdst); 2671 if (IS_ERR(xdst)) { 2672 dst_release(dst); 2673 goto put_states; 2674 } 2675 2676 bundle[i] = xdst; 2677 if (!xdst_prev) 2678 xdst0 = xdst; 2679 else 2680 /* Ref count is taken during xfrm_alloc_dst() 2681 * No need to do dst_clone() on dst1 2682 */ 2683 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2684 2685 if (xfrm[i]->sel.family == AF_UNSPEC) { 2686 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2687 xfrm_af2proto(family)); 2688 if (!inner_mode) { 2689 err = -EAFNOSUPPORT; 2690 dst_release(dst); 2691 goto put_states; 2692 } 2693 } else 2694 inner_mode = &xfrm[i]->inner_mode; 2695 2696 xdst->route = dst; 2697 dst_copy_metrics(dst1, dst); 2698 2699 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2700 __u32 mark = 0; 2701 int oif; 2702 2703 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2704 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2705 2706 if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET) 2707 family = xfrm[i]->props.family; 2708 2709 oif = fl->flowi_oif ? : fl->flowi_l3mdev; 2710 dst = xfrm_dst_lookup(xfrm[i], tos, oif, 2711 &saddr, &daddr, family, mark); 2712 err = PTR_ERR(dst); 2713 if (IS_ERR(dst)) 2714 goto put_states; 2715 } else 2716 dst_hold(dst); 2717 2718 dst1->xfrm = xfrm[i]; 2719 xdst->xfrm_genid = xfrm[i]->genid; 2720 2721 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2722 dst1->lastuse = now; 2723 2724 dst1->input = dst_discard; 2725 2726 rcu_read_lock(); 2727 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2728 if (likely(afinfo)) 2729 dst1->output = afinfo->output; 2730 else 2731 dst1->output = dst_discard_out; 2732 rcu_read_unlock(); 2733 2734 xdst_prev = xdst; 2735 2736 header_len += xfrm[i]->props.header_len; 2737 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2738 nfheader_len += xfrm[i]->props.header_len; 2739 trailer_len += xfrm[i]->props.trailer_len; 2740 } 2741 2742 xfrm_dst_set_child(xdst_prev, dst); 2743 xdst0->path = dst; 2744 2745 err = -ENODEV; 2746 dev = dst->dev; 2747 if (!dev) 2748 goto free_dst; 2749 2750 xfrm_init_path(xdst0, dst, nfheader_len); 2751 xfrm_init_pmtu(bundle, nx); 2752 2753 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2754 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2755 err = xfrm_fill_dst(xdst_prev, dev, fl); 2756 if (err) 2757 goto free_dst; 2758 2759 xdst_prev->u.dst.header_len = header_len; 2760 xdst_prev->u.dst.trailer_len = trailer_len; 2761 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2762 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2763 } 2764 2765 return &xdst0->u.dst; 2766 2767 put_states: 2768 for (; i < nx; i++) 2769 xfrm_state_put(xfrm[i]); 2770 free_dst: 2771 if (xdst0) 2772 dst_release_immediate(&xdst0->u.dst); 2773 2774 return ERR_PTR(err); 2775 } 2776 2777 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2778 struct xfrm_policy **pols, 2779 int *num_pols, int *num_xfrms) 2780 { 2781 int i; 2782 2783 if (*num_pols == 0 || !pols[0]) { 2784 *num_pols = 0; 2785 *num_xfrms = 0; 2786 return 0; 2787 } 2788 if (IS_ERR(pols[0])) { 2789 *num_pols = 0; 2790 return PTR_ERR(pols[0]); 2791 } 2792 2793 *num_xfrms = pols[0]->xfrm_nr; 2794 2795 #ifdef CONFIG_XFRM_SUB_POLICY 2796 if (pols[0]->action == XFRM_POLICY_ALLOW && 2797 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2798 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2799 XFRM_POLICY_TYPE_MAIN, 2800 fl, family, 2801 XFRM_POLICY_OUT, 2802 pols[0]->if_id); 2803 if (pols[1]) { 2804 if (IS_ERR(pols[1])) { 2805 xfrm_pols_put(pols, *num_pols); 2806 *num_pols = 0; 2807 return PTR_ERR(pols[1]); 2808 } 2809 (*num_pols)++; 2810 (*num_xfrms) += pols[1]->xfrm_nr; 2811 } 2812 } 2813 #endif 2814 for (i = 0; i < *num_pols; i++) { 2815 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2816 *num_xfrms = -1; 2817 break; 2818 } 2819 } 2820 2821 return 0; 2822 2823 } 2824 2825 static struct xfrm_dst * 2826 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2827 const struct flowi *fl, u16 family, 2828 struct dst_entry *dst_orig) 2829 { 2830 struct net *net = xp_net(pols[0]); 2831 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2832 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2833 struct xfrm_dst *xdst; 2834 struct dst_entry *dst; 2835 int err; 2836 2837 /* Try to instantiate a bundle */ 2838 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2839 if (err <= 0) { 2840 if (err == 0) 2841 return NULL; 2842 2843 if (err != -EAGAIN) 2844 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2845 return ERR_PTR(err); 2846 } 2847 2848 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2849 if (IS_ERR(dst)) { 2850 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2851 return ERR_CAST(dst); 2852 } 2853 2854 xdst = (struct xfrm_dst *)dst; 2855 xdst->num_xfrms = err; 2856 xdst->num_pols = num_pols; 2857 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2858 xdst->policy_genid = atomic_read(&pols[0]->genid); 2859 2860 return xdst; 2861 } 2862 2863 static void xfrm_policy_queue_process(struct timer_list *t) 2864 { 2865 struct sk_buff *skb; 2866 struct sock *sk; 2867 struct dst_entry *dst; 2868 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2869 struct net *net = xp_net(pol); 2870 struct xfrm_policy_queue *pq = &pol->polq; 2871 struct flowi fl; 2872 struct sk_buff_head list; 2873 __u32 skb_mark; 2874 2875 spin_lock(&pq->hold_queue.lock); 2876 skb = skb_peek(&pq->hold_queue); 2877 if (!skb) { 2878 spin_unlock(&pq->hold_queue.lock); 2879 goto out; 2880 } 2881 dst = skb_dst(skb); 2882 sk = skb->sk; 2883 2884 /* Fixup the mark to support VTI. */ 2885 skb_mark = skb->mark; 2886 skb->mark = pol->mark.v; 2887 xfrm_decode_session(skb, &fl, dst->ops->family); 2888 skb->mark = skb_mark; 2889 spin_unlock(&pq->hold_queue.lock); 2890 2891 dst_hold(xfrm_dst_path(dst)); 2892 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2893 if (IS_ERR(dst)) 2894 goto purge_queue; 2895 2896 if (dst->flags & DST_XFRM_QUEUE) { 2897 dst_release(dst); 2898 2899 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2900 goto purge_queue; 2901 2902 pq->timeout = pq->timeout << 1; 2903 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2904 xfrm_pol_hold(pol); 2905 goto out; 2906 } 2907 2908 dst_release(dst); 2909 2910 __skb_queue_head_init(&list); 2911 2912 spin_lock(&pq->hold_queue.lock); 2913 pq->timeout = 0; 2914 skb_queue_splice_init(&pq->hold_queue, &list); 2915 spin_unlock(&pq->hold_queue.lock); 2916 2917 while (!skb_queue_empty(&list)) { 2918 skb = __skb_dequeue(&list); 2919 2920 /* Fixup the mark to support VTI. */ 2921 skb_mark = skb->mark; 2922 skb->mark = pol->mark.v; 2923 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2924 skb->mark = skb_mark; 2925 2926 dst_hold(xfrm_dst_path(skb_dst(skb))); 2927 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2928 if (IS_ERR(dst)) { 2929 kfree_skb(skb); 2930 continue; 2931 } 2932 2933 nf_reset_ct(skb); 2934 skb_dst_drop(skb); 2935 skb_dst_set(skb, dst); 2936 2937 dst_output(net, skb->sk, skb); 2938 } 2939 2940 out: 2941 xfrm_pol_put(pol); 2942 return; 2943 2944 purge_queue: 2945 pq->timeout = 0; 2946 skb_queue_purge(&pq->hold_queue); 2947 xfrm_pol_put(pol); 2948 } 2949 2950 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2951 { 2952 unsigned long sched_next; 2953 struct dst_entry *dst = skb_dst(skb); 2954 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2955 struct xfrm_policy *pol = xdst->pols[0]; 2956 struct xfrm_policy_queue *pq = &pol->polq; 2957 2958 if (unlikely(skb_fclone_busy(sk, skb))) { 2959 kfree_skb(skb); 2960 return 0; 2961 } 2962 2963 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2964 kfree_skb(skb); 2965 return -EAGAIN; 2966 } 2967 2968 skb_dst_force(skb); 2969 2970 spin_lock_bh(&pq->hold_queue.lock); 2971 2972 if (!pq->timeout) 2973 pq->timeout = XFRM_QUEUE_TMO_MIN; 2974 2975 sched_next = jiffies + pq->timeout; 2976 2977 if (del_timer(&pq->hold_timer)) { 2978 if (time_before(pq->hold_timer.expires, sched_next)) 2979 sched_next = pq->hold_timer.expires; 2980 xfrm_pol_put(pol); 2981 } 2982 2983 __skb_queue_tail(&pq->hold_queue, skb); 2984 if (!mod_timer(&pq->hold_timer, sched_next)) 2985 xfrm_pol_hold(pol); 2986 2987 spin_unlock_bh(&pq->hold_queue.lock); 2988 2989 return 0; 2990 } 2991 2992 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2993 struct xfrm_flo *xflo, 2994 const struct flowi *fl, 2995 int num_xfrms, 2996 u16 family) 2997 { 2998 int err; 2999 struct net_device *dev; 3000 struct dst_entry *dst; 3001 struct dst_entry *dst1; 3002 struct xfrm_dst *xdst; 3003 3004 xdst = xfrm_alloc_dst(net, family); 3005 if (IS_ERR(xdst)) 3006 return xdst; 3007 3008 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 3009 net->xfrm.sysctl_larval_drop || 3010 num_xfrms <= 0) 3011 return xdst; 3012 3013 dst = xflo->dst_orig; 3014 dst1 = &xdst->u.dst; 3015 dst_hold(dst); 3016 xdst->route = dst; 3017 3018 dst_copy_metrics(dst1, dst); 3019 3020 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 3021 dst1->flags |= DST_XFRM_QUEUE; 3022 dst1->lastuse = jiffies; 3023 3024 dst1->input = dst_discard; 3025 dst1->output = xdst_queue_output; 3026 3027 dst_hold(dst); 3028 xfrm_dst_set_child(xdst, dst); 3029 xdst->path = dst; 3030 3031 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 3032 3033 err = -ENODEV; 3034 dev = dst->dev; 3035 if (!dev) 3036 goto free_dst; 3037 3038 err = xfrm_fill_dst(xdst, dev, fl); 3039 if (err) 3040 goto free_dst; 3041 3042 out: 3043 return xdst; 3044 3045 free_dst: 3046 dst_release(dst1); 3047 xdst = ERR_PTR(err); 3048 goto out; 3049 } 3050 3051 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 3052 const struct flowi *fl, 3053 u16 family, u8 dir, 3054 struct xfrm_flo *xflo, u32 if_id) 3055 { 3056 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3057 int num_pols = 0, num_xfrms = 0, err; 3058 struct xfrm_dst *xdst; 3059 3060 /* Resolve policies to use if we couldn't get them from 3061 * previous cache entry */ 3062 num_pols = 1; 3063 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 3064 err = xfrm_expand_policies(fl, family, pols, 3065 &num_pols, &num_xfrms); 3066 if (err < 0) 3067 goto inc_error; 3068 if (num_pols == 0) 3069 return NULL; 3070 if (num_xfrms <= 0) 3071 goto make_dummy_bundle; 3072 3073 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 3074 xflo->dst_orig); 3075 if (IS_ERR(xdst)) { 3076 err = PTR_ERR(xdst); 3077 if (err == -EREMOTE) { 3078 xfrm_pols_put(pols, num_pols); 3079 return NULL; 3080 } 3081 3082 if (err != -EAGAIN) 3083 goto error; 3084 goto make_dummy_bundle; 3085 } else if (xdst == NULL) { 3086 num_xfrms = 0; 3087 goto make_dummy_bundle; 3088 } 3089 3090 return xdst; 3091 3092 make_dummy_bundle: 3093 /* We found policies, but there's no bundles to instantiate: 3094 * either because the policy blocks, has no transformations or 3095 * we could not build template (no xfrm_states).*/ 3096 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 3097 if (IS_ERR(xdst)) { 3098 xfrm_pols_put(pols, num_pols); 3099 return ERR_CAST(xdst); 3100 } 3101 xdst->num_pols = num_pols; 3102 xdst->num_xfrms = num_xfrms; 3103 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 3104 3105 return xdst; 3106 3107 inc_error: 3108 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 3109 error: 3110 xfrm_pols_put(pols, num_pols); 3111 return ERR_PTR(err); 3112 } 3113 3114 static struct dst_entry *make_blackhole(struct net *net, u16 family, 3115 struct dst_entry *dst_orig) 3116 { 3117 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 3118 struct dst_entry *ret; 3119 3120 if (!afinfo) { 3121 dst_release(dst_orig); 3122 return ERR_PTR(-EINVAL); 3123 } else { 3124 ret = afinfo->blackhole_route(net, dst_orig); 3125 } 3126 rcu_read_unlock(); 3127 3128 return ret; 3129 } 3130 3131 /* Finds/creates a bundle for given flow and if_id 3132 * 3133 * At the moment we eat a raw IP route. Mostly to speed up lookups 3134 * on interfaces with disabled IPsec. 3135 * 3136 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3137 * compatibility 3138 */ 3139 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3140 struct dst_entry *dst_orig, 3141 const struct flowi *fl, 3142 const struct sock *sk, 3143 int flags, u32 if_id) 3144 { 3145 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3146 struct xfrm_dst *xdst; 3147 struct dst_entry *dst, *route; 3148 u16 family = dst_orig->ops->family; 3149 u8 dir = XFRM_POLICY_OUT; 3150 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3151 3152 dst = NULL; 3153 xdst = NULL; 3154 route = NULL; 3155 3156 sk = sk_const_to_full_sk(sk); 3157 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3158 num_pols = 1; 3159 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3160 if_id); 3161 err = xfrm_expand_policies(fl, family, pols, 3162 &num_pols, &num_xfrms); 3163 if (err < 0) 3164 goto dropdst; 3165 3166 if (num_pols) { 3167 if (num_xfrms <= 0) { 3168 drop_pols = num_pols; 3169 goto no_transform; 3170 } 3171 3172 xdst = xfrm_resolve_and_create_bundle( 3173 pols, num_pols, fl, 3174 family, dst_orig); 3175 3176 if (IS_ERR(xdst)) { 3177 xfrm_pols_put(pols, num_pols); 3178 err = PTR_ERR(xdst); 3179 if (err == -EREMOTE) 3180 goto nopol; 3181 3182 goto dropdst; 3183 } else if (xdst == NULL) { 3184 num_xfrms = 0; 3185 drop_pols = num_pols; 3186 goto no_transform; 3187 } 3188 3189 route = xdst->route; 3190 } 3191 } 3192 3193 if (xdst == NULL) { 3194 struct xfrm_flo xflo; 3195 3196 xflo.dst_orig = dst_orig; 3197 xflo.flags = flags; 3198 3199 /* To accelerate a bit... */ 3200 if (!if_id && ((dst_orig->flags & DST_NOXFRM) || 3201 !net->xfrm.policy_count[XFRM_POLICY_OUT])) 3202 goto nopol; 3203 3204 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3205 if (xdst == NULL) 3206 goto nopol; 3207 if (IS_ERR(xdst)) { 3208 err = PTR_ERR(xdst); 3209 goto dropdst; 3210 } 3211 3212 num_pols = xdst->num_pols; 3213 num_xfrms = xdst->num_xfrms; 3214 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3215 route = xdst->route; 3216 } 3217 3218 dst = &xdst->u.dst; 3219 if (route == NULL && num_xfrms > 0) { 3220 /* The only case when xfrm_bundle_lookup() returns a 3221 * bundle with null route, is when the template could 3222 * not be resolved. It means policies are there, but 3223 * bundle could not be created, since we don't yet 3224 * have the xfrm_state's. We need to wait for KM to 3225 * negotiate new SA's or bail out with error.*/ 3226 if (net->xfrm.sysctl_larval_drop) { 3227 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3228 err = -EREMOTE; 3229 goto error; 3230 } 3231 3232 err = -EAGAIN; 3233 3234 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3235 goto error; 3236 } 3237 3238 no_transform: 3239 if (num_pols == 0) 3240 goto nopol; 3241 3242 if ((flags & XFRM_LOOKUP_ICMP) && 3243 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3244 err = -ENOENT; 3245 goto error; 3246 } 3247 3248 for (i = 0; i < num_pols; i++) 3249 WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds()); 3250 3251 if (num_xfrms < 0) { 3252 /* Prohibit the flow */ 3253 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3254 err = -EPERM; 3255 goto error; 3256 } else if (num_xfrms > 0) { 3257 /* Flow transformed */ 3258 dst_release(dst_orig); 3259 } else { 3260 /* Flow passes untransformed */ 3261 dst_release(dst); 3262 dst = dst_orig; 3263 } 3264 ok: 3265 xfrm_pols_put(pols, drop_pols); 3266 if (dst && dst->xfrm && 3267 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3268 dst->flags |= DST_XFRM_TUNNEL; 3269 return dst; 3270 3271 nopol: 3272 if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) && 3273 net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { 3274 err = -EPERM; 3275 goto error; 3276 } 3277 if (!(flags & XFRM_LOOKUP_ICMP)) { 3278 dst = dst_orig; 3279 goto ok; 3280 } 3281 err = -ENOENT; 3282 error: 3283 dst_release(dst); 3284 dropdst: 3285 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3286 dst_release(dst_orig); 3287 xfrm_pols_put(pols, drop_pols); 3288 return ERR_PTR(err); 3289 } 3290 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3291 3292 /* Main function: finds/creates a bundle for given flow. 3293 * 3294 * At the moment we eat a raw IP route. Mostly to speed up lookups 3295 * on interfaces with disabled IPsec. 3296 */ 3297 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3298 const struct flowi *fl, const struct sock *sk, 3299 int flags) 3300 { 3301 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3302 } 3303 EXPORT_SYMBOL(xfrm_lookup); 3304 3305 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3306 * Otherwise we may send out blackholed packets. 3307 */ 3308 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3309 const struct flowi *fl, 3310 const struct sock *sk, int flags) 3311 { 3312 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3313 flags | XFRM_LOOKUP_QUEUE | 3314 XFRM_LOOKUP_KEEP_DST_REF); 3315 3316 if (PTR_ERR(dst) == -EREMOTE) 3317 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3318 3319 if (IS_ERR(dst)) 3320 dst_release(dst_orig); 3321 3322 return dst; 3323 } 3324 EXPORT_SYMBOL(xfrm_lookup_route); 3325 3326 static inline int 3327 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3328 { 3329 struct sec_path *sp = skb_sec_path(skb); 3330 struct xfrm_state *x; 3331 3332 if (!sp || idx < 0 || idx >= sp->len) 3333 return 0; 3334 x = sp->xvec[idx]; 3335 if (!x->type->reject) 3336 return 0; 3337 return x->type->reject(x, skb, fl); 3338 } 3339 3340 /* When skb is transformed back to its "native" form, we have to 3341 * check policy restrictions. At the moment we make this in maximally 3342 * stupid way. Shame on me. :-) Of course, connected sockets must 3343 * have policy cached at them. 3344 */ 3345 3346 static inline int 3347 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3348 unsigned short family, u32 if_id) 3349 { 3350 if (xfrm_state_kern(x)) 3351 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3352 return x->id.proto == tmpl->id.proto && 3353 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3354 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3355 x->props.mode == tmpl->mode && 3356 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3357 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3358 !(x->props.mode != XFRM_MODE_TRANSPORT && 3359 xfrm_state_addr_cmp(tmpl, x, family)) && 3360 (if_id == 0 || if_id == x->if_id); 3361 } 3362 3363 /* 3364 * 0 or more than 0 is returned when validation is succeeded (either bypass 3365 * because of optional transport mode, or next index of the matched secpath 3366 * state with the template. 3367 * -1 is returned when no matching template is found. 3368 * Otherwise "-2 - errored_index" is returned. 3369 */ 3370 static inline int 3371 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3372 unsigned short family, u32 if_id) 3373 { 3374 int idx = start; 3375 3376 if (tmpl->optional) { 3377 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3378 return start; 3379 } else 3380 start = -1; 3381 for (; idx < sp->len; idx++) { 3382 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id)) 3383 return ++idx; 3384 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3385 if (idx < sp->verified_cnt) { 3386 /* Secpath entry previously verified, consider optional and 3387 * continue searching 3388 */ 3389 continue; 3390 } 3391 3392 if (start == -1) 3393 start = -2-idx; 3394 break; 3395 } 3396 } 3397 return start; 3398 } 3399 3400 static void 3401 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3402 { 3403 const struct iphdr *iph = ip_hdr(skb); 3404 int ihl = iph->ihl; 3405 u8 *xprth = skb_network_header(skb) + ihl * 4; 3406 struct flowi4 *fl4 = &fl->u.ip4; 3407 int oif = 0; 3408 3409 if (skb_dst(skb) && skb_dst(skb)->dev) 3410 oif = skb_dst(skb)->dev->ifindex; 3411 3412 memset(fl4, 0, sizeof(struct flowi4)); 3413 fl4->flowi4_mark = skb->mark; 3414 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3415 3416 fl4->flowi4_proto = iph->protocol; 3417 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3418 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3419 fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK; 3420 3421 if (!ip_is_fragment(iph)) { 3422 switch (iph->protocol) { 3423 case IPPROTO_UDP: 3424 case IPPROTO_UDPLITE: 3425 case IPPROTO_TCP: 3426 case IPPROTO_SCTP: 3427 case IPPROTO_DCCP: 3428 if (xprth + 4 < skb->data || 3429 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3430 __be16 *ports; 3431 3432 xprth = skb_network_header(skb) + ihl * 4; 3433 ports = (__be16 *)xprth; 3434 3435 fl4->fl4_sport = ports[!!reverse]; 3436 fl4->fl4_dport = ports[!reverse]; 3437 } 3438 break; 3439 case IPPROTO_ICMP: 3440 if (xprth + 2 < skb->data || 3441 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3442 u8 *icmp; 3443 3444 xprth = skb_network_header(skb) + ihl * 4; 3445 icmp = xprth; 3446 3447 fl4->fl4_icmp_type = icmp[0]; 3448 fl4->fl4_icmp_code = icmp[1]; 3449 } 3450 break; 3451 case IPPROTO_GRE: 3452 if (xprth + 12 < skb->data || 3453 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3454 __be16 *greflags; 3455 __be32 *gre_hdr; 3456 3457 xprth = skb_network_header(skb) + ihl * 4; 3458 greflags = (__be16 *)xprth; 3459 gre_hdr = (__be32 *)xprth; 3460 3461 if (greflags[0] & GRE_KEY) { 3462 if (greflags[0] & GRE_CSUM) 3463 gre_hdr++; 3464 fl4->fl4_gre_key = gre_hdr[1]; 3465 } 3466 } 3467 break; 3468 default: 3469 break; 3470 } 3471 } 3472 } 3473 3474 #if IS_ENABLED(CONFIG_IPV6) 3475 static void 3476 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3477 { 3478 struct flowi6 *fl6 = &fl->u.ip6; 3479 int onlyproto = 0; 3480 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3481 u32 offset = sizeof(*hdr); 3482 struct ipv6_opt_hdr *exthdr; 3483 const unsigned char *nh = skb_network_header(skb); 3484 u16 nhoff = IP6CB(skb)->nhoff; 3485 int oif = 0; 3486 u8 nexthdr; 3487 3488 if (!nhoff) 3489 nhoff = offsetof(struct ipv6hdr, nexthdr); 3490 3491 nexthdr = nh[nhoff]; 3492 3493 if (skb_dst(skb) && skb_dst(skb)->dev) 3494 oif = skb_dst(skb)->dev->ifindex; 3495 3496 memset(fl6, 0, sizeof(struct flowi6)); 3497 fl6->flowi6_mark = skb->mark; 3498 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3499 3500 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3501 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3502 3503 while (nh + offset + sizeof(*exthdr) < skb->data || 3504 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3505 nh = skb_network_header(skb); 3506 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3507 3508 switch (nexthdr) { 3509 case NEXTHDR_FRAGMENT: 3510 onlyproto = 1; 3511 fallthrough; 3512 case NEXTHDR_ROUTING: 3513 case NEXTHDR_HOP: 3514 case NEXTHDR_DEST: 3515 offset += ipv6_optlen(exthdr); 3516 nexthdr = exthdr->nexthdr; 3517 break; 3518 case IPPROTO_UDP: 3519 case IPPROTO_UDPLITE: 3520 case IPPROTO_TCP: 3521 case IPPROTO_SCTP: 3522 case IPPROTO_DCCP: 3523 if (!onlyproto && (nh + offset + 4 < skb->data || 3524 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3525 __be16 *ports; 3526 3527 nh = skb_network_header(skb); 3528 ports = (__be16 *)(nh + offset); 3529 fl6->fl6_sport = ports[!!reverse]; 3530 fl6->fl6_dport = ports[!reverse]; 3531 } 3532 fl6->flowi6_proto = nexthdr; 3533 return; 3534 case IPPROTO_ICMPV6: 3535 if (!onlyproto && (nh + offset + 2 < skb->data || 3536 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3537 u8 *icmp; 3538 3539 nh = skb_network_header(skb); 3540 icmp = (u8 *)(nh + offset); 3541 fl6->fl6_icmp_type = icmp[0]; 3542 fl6->fl6_icmp_code = icmp[1]; 3543 } 3544 fl6->flowi6_proto = nexthdr; 3545 return; 3546 case IPPROTO_GRE: 3547 if (!onlyproto && 3548 (nh + offset + 12 < skb->data || 3549 pskb_may_pull(skb, nh + offset + 12 - skb->data))) { 3550 struct gre_base_hdr *gre_hdr; 3551 __be32 *gre_key; 3552 3553 nh = skb_network_header(skb); 3554 gre_hdr = (struct gre_base_hdr *)(nh + offset); 3555 gre_key = (__be32 *)(gre_hdr + 1); 3556 3557 if (gre_hdr->flags & GRE_KEY) { 3558 if (gre_hdr->flags & GRE_CSUM) 3559 gre_key++; 3560 fl6->fl6_gre_key = *gre_key; 3561 } 3562 } 3563 fl6->flowi6_proto = nexthdr; 3564 return; 3565 3566 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3567 case IPPROTO_MH: 3568 offset += ipv6_optlen(exthdr); 3569 if (!onlyproto && (nh + offset + 3 < skb->data || 3570 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3571 struct ip6_mh *mh; 3572 3573 nh = skb_network_header(skb); 3574 mh = (struct ip6_mh *)(nh + offset); 3575 fl6->fl6_mh_type = mh->ip6mh_type; 3576 } 3577 fl6->flowi6_proto = nexthdr; 3578 return; 3579 #endif 3580 default: 3581 fl6->flowi6_proto = nexthdr; 3582 return; 3583 } 3584 } 3585 } 3586 #endif 3587 3588 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3589 unsigned int family, int reverse) 3590 { 3591 switch (family) { 3592 case AF_INET: 3593 decode_session4(skb, fl, reverse); 3594 break; 3595 #if IS_ENABLED(CONFIG_IPV6) 3596 case AF_INET6: 3597 decode_session6(skb, fl, reverse); 3598 break; 3599 #endif 3600 default: 3601 return -EAFNOSUPPORT; 3602 } 3603 3604 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3605 } 3606 EXPORT_SYMBOL(__xfrm_decode_session); 3607 3608 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3609 { 3610 for (; k < sp->len; k++) { 3611 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3612 *idxp = k; 3613 return 1; 3614 } 3615 } 3616 3617 return 0; 3618 } 3619 3620 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3621 unsigned short family) 3622 { 3623 struct net *net = dev_net(skb->dev); 3624 struct xfrm_policy *pol; 3625 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3626 int npols = 0; 3627 int xfrm_nr; 3628 int pi; 3629 int reverse; 3630 struct flowi fl; 3631 int xerr_idx = -1; 3632 const struct xfrm_if_cb *ifcb; 3633 struct sec_path *sp; 3634 u32 if_id = 0; 3635 3636 rcu_read_lock(); 3637 ifcb = xfrm_if_get_cb(); 3638 3639 if (ifcb) { 3640 struct xfrm_if_decode_session_result r; 3641 3642 if (ifcb->decode_session(skb, family, &r)) { 3643 if_id = r.if_id; 3644 net = r.net; 3645 } 3646 } 3647 rcu_read_unlock(); 3648 3649 reverse = dir & ~XFRM_POLICY_MASK; 3650 dir &= XFRM_POLICY_MASK; 3651 3652 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3653 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3654 return 0; 3655 } 3656 3657 nf_nat_decode_session(skb, &fl, family); 3658 3659 /* First, check used SA against their selectors. */ 3660 sp = skb_sec_path(skb); 3661 if (sp) { 3662 int i; 3663 3664 for (i = sp->len - 1; i >= 0; i--) { 3665 struct xfrm_state *x = sp->xvec[i]; 3666 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3667 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3668 return 0; 3669 } 3670 } 3671 } 3672 3673 pol = NULL; 3674 sk = sk_to_full_sk(sk); 3675 if (sk && sk->sk_policy[dir]) { 3676 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3677 if (IS_ERR(pol)) { 3678 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3679 return 0; 3680 } 3681 } 3682 3683 if (!pol) 3684 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3685 3686 if (IS_ERR(pol)) { 3687 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3688 return 0; 3689 } 3690 3691 if (!pol) { 3692 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { 3693 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3694 return 0; 3695 } 3696 3697 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3698 xfrm_secpath_reject(xerr_idx, skb, &fl); 3699 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3700 return 0; 3701 } 3702 return 1; 3703 } 3704 3705 /* This lockless write can happen from different cpus. */ 3706 WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds()); 3707 3708 pols[0] = pol; 3709 npols++; 3710 #ifdef CONFIG_XFRM_SUB_POLICY 3711 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3712 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3713 &fl, family, 3714 XFRM_POLICY_IN, if_id); 3715 if (pols[1]) { 3716 if (IS_ERR(pols[1])) { 3717 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3718 xfrm_pol_put(pols[0]); 3719 return 0; 3720 } 3721 /* This write can happen from different cpus. */ 3722 WRITE_ONCE(pols[1]->curlft.use_time, 3723 ktime_get_real_seconds()); 3724 npols++; 3725 } 3726 } 3727 #endif 3728 3729 if (pol->action == XFRM_POLICY_ALLOW) { 3730 static struct sec_path dummy; 3731 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3732 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3733 struct xfrm_tmpl **tpp = tp; 3734 int ti = 0; 3735 int i, k; 3736 3737 sp = skb_sec_path(skb); 3738 if (!sp) 3739 sp = &dummy; 3740 3741 for (pi = 0; pi < npols; pi++) { 3742 if (pols[pi] != pol && 3743 pols[pi]->action != XFRM_POLICY_ALLOW) { 3744 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3745 goto reject; 3746 } 3747 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3748 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3749 goto reject_error; 3750 } 3751 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3752 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3753 } 3754 xfrm_nr = ti; 3755 3756 if (npols > 1) { 3757 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3758 tpp = stp; 3759 } 3760 3761 /* For each tunnel xfrm, find the first matching tmpl. 3762 * For each tmpl before that, find corresponding xfrm. 3763 * Order is _important_. Later we will implement 3764 * some barriers, but at the moment barriers 3765 * are implied between each two transformations. 3766 * Upon success, marks secpath entries as having been 3767 * verified to allow them to be skipped in future policy 3768 * checks (e.g. nested tunnels). 3769 */ 3770 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3771 k = xfrm_policy_ok(tpp[i], sp, k, family, if_id); 3772 if (k < 0) { 3773 if (k < -1) 3774 /* "-2 - errored_index" returned */ 3775 xerr_idx = -(2+k); 3776 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3777 goto reject; 3778 } 3779 } 3780 3781 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3782 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3783 goto reject; 3784 } 3785 3786 xfrm_pols_put(pols, npols); 3787 sp->verified_cnt = k; 3788 3789 return 1; 3790 } 3791 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3792 3793 reject: 3794 xfrm_secpath_reject(xerr_idx, skb, &fl); 3795 reject_error: 3796 xfrm_pols_put(pols, npols); 3797 return 0; 3798 } 3799 EXPORT_SYMBOL(__xfrm_policy_check); 3800 3801 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3802 { 3803 struct net *net = dev_net(skb->dev); 3804 struct flowi fl; 3805 struct dst_entry *dst; 3806 int res = 1; 3807 3808 if (xfrm_decode_session(skb, &fl, family) < 0) { 3809 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3810 return 0; 3811 } 3812 3813 skb_dst_force(skb); 3814 if (!skb_dst(skb)) { 3815 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3816 return 0; 3817 } 3818 3819 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3820 if (IS_ERR(dst)) { 3821 res = 0; 3822 dst = NULL; 3823 } 3824 skb_dst_set(skb, dst); 3825 return res; 3826 } 3827 EXPORT_SYMBOL(__xfrm_route_forward); 3828 3829 /* Optimize later using cookies and generation ids. */ 3830 3831 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3832 { 3833 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3834 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3835 * get validated by dst_ops->check on every use. We do this 3836 * because when a normal route referenced by an XFRM dst is 3837 * obsoleted we do not go looking around for all parent 3838 * referencing XFRM dsts so that we can invalidate them. It 3839 * is just too much work. Instead we make the checks here on 3840 * every use. For example: 3841 * 3842 * XFRM dst A --> IPv4 dst X 3843 * 3844 * X is the "xdst->route" of A (X is also the "dst->path" of A 3845 * in this example). If X is marked obsolete, "A" will not 3846 * notice. That's what we are validating here via the 3847 * stale_bundle() check. 3848 * 3849 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3850 * be marked on it. 3851 * This will force stale_bundle() to fail on any xdst bundle with 3852 * this dst linked in it. 3853 */ 3854 if (dst->obsolete < 0 && !stale_bundle(dst)) 3855 return dst; 3856 3857 return NULL; 3858 } 3859 3860 static int stale_bundle(struct dst_entry *dst) 3861 { 3862 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3863 } 3864 3865 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3866 { 3867 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3868 dst->dev = blackhole_netdev; 3869 dev_hold(dst->dev); 3870 dev_put(dev); 3871 } 3872 } 3873 EXPORT_SYMBOL(xfrm_dst_ifdown); 3874 3875 static void xfrm_link_failure(struct sk_buff *skb) 3876 { 3877 /* Impossible. Such dst must be popped before reaches point of failure. */ 3878 } 3879 3880 static void xfrm_negative_advice(struct sock *sk, struct dst_entry *dst) 3881 { 3882 if (dst->obsolete) 3883 sk_dst_reset(sk); 3884 } 3885 3886 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3887 { 3888 while (nr--) { 3889 struct xfrm_dst *xdst = bundle[nr]; 3890 u32 pmtu, route_mtu_cached; 3891 struct dst_entry *dst; 3892 3893 dst = &xdst->u.dst; 3894 pmtu = dst_mtu(xfrm_dst_child(dst)); 3895 xdst->child_mtu_cached = pmtu; 3896 3897 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3898 3899 route_mtu_cached = dst_mtu(xdst->route); 3900 xdst->route_mtu_cached = route_mtu_cached; 3901 3902 if (pmtu > route_mtu_cached) 3903 pmtu = route_mtu_cached; 3904 3905 dst_metric_set(dst, RTAX_MTU, pmtu); 3906 } 3907 } 3908 3909 /* Check that the bundle accepts the flow and its components are 3910 * still valid. 3911 */ 3912 3913 static int xfrm_bundle_ok(struct xfrm_dst *first) 3914 { 3915 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3916 struct dst_entry *dst = &first->u.dst; 3917 struct xfrm_dst *xdst; 3918 int start_from, nr; 3919 u32 mtu; 3920 3921 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3922 (dst->dev && !netif_running(dst->dev))) 3923 return 0; 3924 3925 if (dst->flags & DST_XFRM_QUEUE) 3926 return 1; 3927 3928 start_from = nr = 0; 3929 do { 3930 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3931 3932 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3933 return 0; 3934 if (xdst->xfrm_genid != dst->xfrm->genid) 3935 return 0; 3936 if (xdst->num_pols > 0 && 3937 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3938 return 0; 3939 3940 bundle[nr++] = xdst; 3941 3942 mtu = dst_mtu(xfrm_dst_child(dst)); 3943 if (xdst->child_mtu_cached != mtu) { 3944 start_from = nr; 3945 xdst->child_mtu_cached = mtu; 3946 } 3947 3948 if (!dst_check(xdst->route, xdst->route_cookie)) 3949 return 0; 3950 mtu = dst_mtu(xdst->route); 3951 if (xdst->route_mtu_cached != mtu) { 3952 start_from = nr; 3953 xdst->route_mtu_cached = mtu; 3954 } 3955 3956 dst = xfrm_dst_child(dst); 3957 } while (dst->xfrm); 3958 3959 if (likely(!start_from)) 3960 return 1; 3961 3962 xdst = bundle[start_from - 1]; 3963 mtu = xdst->child_mtu_cached; 3964 while (start_from--) { 3965 dst = &xdst->u.dst; 3966 3967 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3968 if (mtu > xdst->route_mtu_cached) 3969 mtu = xdst->route_mtu_cached; 3970 dst_metric_set(dst, RTAX_MTU, mtu); 3971 if (!start_from) 3972 break; 3973 3974 xdst = bundle[start_from - 1]; 3975 xdst->child_mtu_cached = mtu; 3976 } 3977 3978 return 1; 3979 } 3980 3981 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3982 { 3983 return dst_metric_advmss(xfrm_dst_path(dst)); 3984 } 3985 3986 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3987 { 3988 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3989 3990 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3991 } 3992 3993 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3994 const void *daddr) 3995 { 3996 while (dst->xfrm) { 3997 const struct xfrm_state *xfrm = dst->xfrm; 3998 3999 dst = xfrm_dst_child(dst); 4000 4001 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 4002 continue; 4003 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 4004 daddr = xfrm->coaddr; 4005 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 4006 daddr = &xfrm->id.daddr; 4007 } 4008 return daddr; 4009 } 4010 4011 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 4012 struct sk_buff *skb, 4013 const void *daddr) 4014 { 4015 const struct dst_entry *path = xfrm_dst_path(dst); 4016 4017 if (!skb) 4018 daddr = xfrm_get_dst_nexthop(dst, daddr); 4019 return path->ops->neigh_lookup(path, skb, daddr); 4020 } 4021 4022 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 4023 { 4024 const struct dst_entry *path = xfrm_dst_path(dst); 4025 4026 daddr = xfrm_get_dst_nexthop(dst, daddr); 4027 path->ops->confirm_neigh(path, daddr); 4028 } 4029 4030 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 4031 { 4032 int err = 0; 4033 4034 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 4035 return -EAFNOSUPPORT; 4036 4037 spin_lock(&xfrm_policy_afinfo_lock); 4038 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 4039 err = -EEXIST; 4040 else { 4041 struct dst_ops *dst_ops = afinfo->dst_ops; 4042 if (likely(dst_ops->kmem_cachep == NULL)) 4043 dst_ops->kmem_cachep = xfrm_dst_cache; 4044 if (likely(dst_ops->check == NULL)) 4045 dst_ops->check = xfrm_dst_check; 4046 if (likely(dst_ops->default_advmss == NULL)) 4047 dst_ops->default_advmss = xfrm_default_advmss; 4048 if (likely(dst_ops->mtu == NULL)) 4049 dst_ops->mtu = xfrm_mtu; 4050 if (likely(dst_ops->negative_advice == NULL)) 4051 dst_ops->negative_advice = xfrm_negative_advice; 4052 if (likely(dst_ops->link_failure == NULL)) 4053 dst_ops->link_failure = xfrm_link_failure; 4054 if (likely(dst_ops->neigh_lookup == NULL)) 4055 dst_ops->neigh_lookup = xfrm_neigh_lookup; 4056 if (likely(!dst_ops->confirm_neigh)) 4057 dst_ops->confirm_neigh = xfrm_confirm_neigh; 4058 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 4059 } 4060 spin_unlock(&xfrm_policy_afinfo_lock); 4061 4062 return err; 4063 } 4064 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 4065 4066 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 4067 { 4068 struct dst_ops *dst_ops = afinfo->dst_ops; 4069 int i; 4070 4071 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 4072 if (xfrm_policy_afinfo[i] != afinfo) 4073 continue; 4074 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 4075 break; 4076 } 4077 4078 synchronize_rcu(); 4079 4080 dst_ops->kmem_cachep = NULL; 4081 dst_ops->check = NULL; 4082 dst_ops->negative_advice = NULL; 4083 dst_ops->link_failure = NULL; 4084 } 4085 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 4086 4087 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 4088 { 4089 spin_lock(&xfrm_if_cb_lock); 4090 rcu_assign_pointer(xfrm_if_cb, ifcb); 4091 spin_unlock(&xfrm_if_cb_lock); 4092 } 4093 EXPORT_SYMBOL(xfrm_if_register_cb); 4094 4095 void xfrm_if_unregister_cb(void) 4096 { 4097 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4098 synchronize_rcu(); 4099 } 4100 EXPORT_SYMBOL(xfrm_if_unregister_cb); 4101 4102 #ifdef CONFIG_XFRM_STATISTICS 4103 static int __net_init xfrm_statistics_init(struct net *net) 4104 { 4105 int rv; 4106 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 4107 if (!net->mib.xfrm_statistics) 4108 return -ENOMEM; 4109 rv = xfrm_proc_init(net); 4110 if (rv < 0) 4111 free_percpu(net->mib.xfrm_statistics); 4112 return rv; 4113 } 4114 4115 static void xfrm_statistics_fini(struct net *net) 4116 { 4117 xfrm_proc_fini(net); 4118 free_percpu(net->mib.xfrm_statistics); 4119 } 4120 #else 4121 static int __net_init xfrm_statistics_init(struct net *net) 4122 { 4123 return 0; 4124 } 4125 4126 static void xfrm_statistics_fini(struct net *net) 4127 { 4128 } 4129 #endif 4130 4131 static int __net_init xfrm_policy_init(struct net *net) 4132 { 4133 unsigned int hmask, sz; 4134 int dir, err; 4135 4136 if (net_eq(net, &init_net)) { 4137 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4138 sizeof(struct xfrm_dst), 4139 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4140 NULL); 4141 err = rhashtable_init(&xfrm_policy_inexact_table, 4142 &xfrm_pol_inexact_params); 4143 BUG_ON(err); 4144 } 4145 4146 hmask = 8 - 1; 4147 sz = (hmask+1) * sizeof(struct hlist_head); 4148 4149 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4150 if (!net->xfrm.policy_byidx) 4151 goto out_byidx; 4152 net->xfrm.policy_idx_hmask = hmask; 4153 4154 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4155 struct xfrm_policy_hash *htab; 4156 4157 net->xfrm.policy_count[dir] = 0; 4158 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4159 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4160 4161 htab = &net->xfrm.policy_bydst[dir]; 4162 htab->table = xfrm_hash_alloc(sz); 4163 if (!htab->table) 4164 goto out_bydst; 4165 htab->hmask = hmask; 4166 htab->dbits4 = 32; 4167 htab->sbits4 = 32; 4168 htab->dbits6 = 128; 4169 htab->sbits6 = 128; 4170 } 4171 net->xfrm.policy_hthresh.lbits4 = 32; 4172 net->xfrm.policy_hthresh.rbits4 = 32; 4173 net->xfrm.policy_hthresh.lbits6 = 128; 4174 net->xfrm.policy_hthresh.rbits6 = 128; 4175 4176 seqlock_init(&net->xfrm.policy_hthresh.lock); 4177 4178 INIT_LIST_HEAD(&net->xfrm.policy_all); 4179 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4180 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4181 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4182 return 0; 4183 4184 out_bydst: 4185 for (dir--; dir >= 0; dir--) { 4186 struct xfrm_policy_hash *htab; 4187 4188 htab = &net->xfrm.policy_bydst[dir]; 4189 xfrm_hash_free(htab->table, sz); 4190 } 4191 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4192 out_byidx: 4193 return -ENOMEM; 4194 } 4195 4196 static void xfrm_policy_fini(struct net *net) 4197 { 4198 struct xfrm_pol_inexact_bin *b, *t; 4199 unsigned int sz; 4200 int dir; 4201 4202 flush_work(&net->xfrm.policy_hash_work); 4203 #ifdef CONFIG_XFRM_SUB_POLICY 4204 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4205 #endif 4206 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4207 4208 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4209 4210 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4211 struct xfrm_policy_hash *htab; 4212 4213 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4214 4215 htab = &net->xfrm.policy_bydst[dir]; 4216 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4217 WARN_ON(!hlist_empty(htab->table)); 4218 xfrm_hash_free(htab->table, sz); 4219 } 4220 4221 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4222 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4223 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4224 4225 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4226 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4227 __xfrm_policy_inexact_prune_bin(b, true); 4228 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4229 } 4230 4231 static int __net_init xfrm_net_init(struct net *net) 4232 { 4233 int rv; 4234 4235 /* Initialize the per-net locks here */ 4236 spin_lock_init(&net->xfrm.xfrm_state_lock); 4237 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4238 seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock); 4239 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4240 net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT; 4241 net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT; 4242 net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT; 4243 4244 rv = xfrm_statistics_init(net); 4245 if (rv < 0) 4246 goto out_statistics; 4247 rv = xfrm_state_init(net); 4248 if (rv < 0) 4249 goto out_state; 4250 rv = xfrm_policy_init(net); 4251 if (rv < 0) 4252 goto out_policy; 4253 rv = xfrm_sysctl_init(net); 4254 if (rv < 0) 4255 goto out_sysctl; 4256 4257 return 0; 4258 4259 out_sysctl: 4260 xfrm_policy_fini(net); 4261 out_policy: 4262 xfrm_state_fini(net); 4263 out_state: 4264 xfrm_statistics_fini(net); 4265 out_statistics: 4266 return rv; 4267 } 4268 4269 static void __net_exit xfrm_net_exit(struct net *net) 4270 { 4271 xfrm_sysctl_fini(net); 4272 xfrm_policy_fini(net); 4273 xfrm_state_fini(net); 4274 xfrm_statistics_fini(net); 4275 } 4276 4277 static struct pernet_operations __net_initdata xfrm_net_ops = { 4278 .init = xfrm_net_init, 4279 .exit = xfrm_net_exit, 4280 }; 4281 4282 void __init xfrm_init(void) 4283 { 4284 register_pernet_subsys(&xfrm_net_ops); 4285 xfrm_dev_init(); 4286 xfrm_input_init(); 4287 4288 #ifdef CONFIG_XFRM_ESPINTCP 4289 espintcp_init(); 4290 #endif 4291 } 4292 4293 #ifdef CONFIG_AUDITSYSCALL 4294 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4295 struct audit_buffer *audit_buf) 4296 { 4297 struct xfrm_sec_ctx *ctx = xp->security; 4298 struct xfrm_selector *sel = &xp->selector; 4299 4300 if (ctx) 4301 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4302 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4303 4304 switch (sel->family) { 4305 case AF_INET: 4306 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4307 if (sel->prefixlen_s != 32) 4308 audit_log_format(audit_buf, " src_prefixlen=%d", 4309 sel->prefixlen_s); 4310 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4311 if (sel->prefixlen_d != 32) 4312 audit_log_format(audit_buf, " dst_prefixlen=%d", 4313 sel->prefixlen_d); 4314 break; 4315 case AF_INET6: 4316 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4317 if (sel->prefixlen_s != 128) 4318 audit_log_format(audit_buf, " src_prefixlen=%d", 4319 sel->prefixlen_s); 4320 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4321 if (sel->prefixlen_d != 128) 4322 audit_log_format(audit_buf, " dst_prefixlen=%d", 4323 sel->prefixlen_d); 4324 break; 4325 } 4326 } 4327 4328 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4329 { 4330 struct audit_buffer *audit_buf; 4331 4332 audit_buf = xfrm_audit_start("SPD-add"); 4333 if (audit_buf == NULL) 4334 return; 4335 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4336 audit_log_format(audit_buf, " res=%u", result); 4337 xfrm_audit_common_policyinfo(xp, audit_buf); 4338 audit_log_end(audit_buf); 4339 } 4340 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4341 4342 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4343 bool task_valid) 4344 { 4345 struct audit_buffer *audit_buf; 4346 4347 audit_buf = xfrm_audit_start("SPD-delete"); 4348 if (audit_buf == NULL) 4349 return; 4350 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4351 audit_log_format(audit_buf, " res=%u", result); 4352 xfrm_audit_common_policyinfo(xp, audit_buf); 4353 audit_log_end(audit_buf); 4354 } 4355 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4356 #endif 4357 4358 #ifdef CONFIG_XFRM_MIGRATE 4359 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4360 const struct xfrm_selector *sel_tgt) 4361 { 4362 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4363 if (sel_tgt->family == sel_cmp->family && 4364 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4365 sel_cmp->family) && 4366 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4367 sel_cmp->family) && 4368 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4369 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4370 return true; 4371 } 4372 } else { 4373 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4374 return true; 4375 } 4376 } 4377 return false; 4378 } 4379 4380 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4381 u8 dir, u8 type, struct net *net, u32 if_id) 4382 { 4383 struct xfrm_policy *pol, *ret = NULL; 4384 struct hlist_head *chain; 4385 u32 priority = ~0U; 4386 4387 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4388 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4389 hlist_for_each_entry(pol, chain, bydst) { 4390 if ((if_id == 0 || pol->if_id == if_id) && 4391 xfrm_migrate_selector_match(sel, &pol->selector) && 4392 pol->type == type) { 4393 ret = pol; 4394 priority = ret->priority; 4395 break; 4396 } 4397 } 4398 chain = &net->xfrm.policy_inexact[dir]; 4399 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4400 if ((pol->priority >= priority) && ret) 4401 break; 4402 4403 if ((if_id == 0 || pol->if_id == if_id) && 4404 xfrm_migrate_selector_match(sel, &pol->selector) && 4405 pol->type == type) { 4406 ret = pol; 4407 break; 4408 } 4409 } 4410 4411 xfrm_pol_hold(ret); 4412 4413 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4414 4415 return ret; 4416 } 4417 4418 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4419 { 4420 int match = 0; 4421 4422 if (t->mode == m->mode && t->id.proto == m->proto && 4423 (m->reqid == 0 || t->reqid == m->reqid)) { 4424 switch (t->mode) { 4425 case XFRM_MODE_TUNNEL: 4426 case XFRM_MODE_BEET: 4427 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4428 m->old_family) && 4429 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4430 m->old_family)) { 4431 match = 1; 4432 } 4433 break; 4434 case XFRM_MODE_TRANSPORT: 4435 /* in case of transport mode, template does not store 4436 any IP addresses, hence we just compare mode and 4437 protocol */ 4438 match = 1; 4439 break; 4440 default: 4441 break; 4442 } 4443 } 4444 return match; 4445 } 4446 4447 /* update endpoint address(es) of template(s) */ 4448 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4449 struct xfrm_migrate *m, int num_migrate, 4450 struct netlink_ext_ack *extack) 4451 { 4452 struct xfrm_migrate *mp; 4453 int i, j, n = 0; 4454 4455 write_lock_bh(&pol->lock); 4456 if (unlikely(pol->walk.dead)) { 4457 /* target policy has been deleted */ 4458 NL_SET_ERR_MSG(extack, "Target policy not found"); 4459 write_unlock_bh(&pol->lock); 4460 return -ENOENT; 4461 } 4462 4463 for (i = 0; i < pol->xfrm_nr; i++) { 4464 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4465 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4466 continue; 4467 n++; 4468 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4469 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4470 continue; 4471 /* update endpoints */ 4472 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4473 sizeof(pol->xfrm_vec[i].id.daddr)); 4474 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4475 sizeof(pol->xfrm_vec[i].saddr)); 4476 pol->xfrm_vec[i].encap_family = mp->new_family; 4477 /* flush bundles */ 4478 atomic_inc(&pol->genid); 4479 } 4480 } 4481 4482 write_unlock_bh(&pol->lock); 4483 4484 if (!n) 4485 return -ENODATA; 4486 4487 return 0; 4488 } 4489 4490 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate, 4491 struct netlink_ext_ack *extack) 4492 { 4493 int i, j; 4494 4495 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) { 4496 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)"); 4497 return -EINVAL; 4498 } 4499 4500 for (i = 0; i < num_migrate; i++) { 4501 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4502 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) { 4503 NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null"); 4504 return -EINVAL; 4505 } 4506 4507 /* check if there is any duplicated entry */ 4508 for (j = i + 1; j < num_migrate; j++) { 4509 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4510 sizeof(m[i].old_daddr)) && 4511 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4512 sizeof(m[i].old_saddr)) && 4513 m[i].proto == m[j].proto && 4514 m[i].mode == m[j].mode && 4515 m[i].reqid == m[j].reqid && 4516 m[i].old_family == m[j].old_family) { 4517 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique"); 4518 return -EINVAL; 4519 } 4520 } 4521 } 4522 4523 return 0; 4524 } 4525 4526 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4527 struct xfrm_migrate *m, int num_migrate, 4528 struct xfrm_kmaddress *k, struct net *net, 4529 struct xfrm_encap_tmpl *encap, u32 if_id, 4530 struct netlink_ext_ack *extack) 4531 { 4532 int i, err, nx_cur = 0, nx_new = 0; 4533 struct xfrm_policy *pol = NULL; 4534 struct xfrm_state *x, *xc; 4535 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4536 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4537 struct xfrm_migrate *mp; 4538 4539 /* Stage 0 - sanity checks */ 4540 err = xfrm_migrate_check(m, num_migrate, extack); 4541 if (err < 0) 4542 goto out; 4543 4544 if (dir >= XFRM_POLICY_MAX) { 4545 NL_SET_ERR_MSG(extack, "Invalid policy direction"); 4546 err = -EINVAL; 4547 goto out; 4548 } 4549 4550 /* Stage 1 - find policy */ 4551 pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id); 4552 if (!pol) { 4553 NL_SET_ERR_MSG(extack, "Target policy not found"); 4554 err = -ENOENT; 4555 goto out; 4556 } 4557 4558 /* Stage 2 - find and update state(s) */ 4559 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4560 if ((x = xfrm_migrate_state_find(mp, net, if_id))) { 4561 x_cur[nx_cur] = x; 4562 nx_cur++; 4563 xc = xfrm_state_migrate(x, mp, encap); 4564 if (xc) { 4565 x_new[nx_new] = xc; 4566 nx_new++; 4567 } else { 4568 err = -ENODATA; 4569 goto restore_state; 4570 } 4571 } 4572 } 4573 4574 /* Stage 3 - update policy */ 4575 err = xfrm_policy_migrate(pol, m, num_migrate, extack); 4576 if (err < 0) 4577 goto restore_state; 4578 4579 /* Stage 4 - delete old state(s) */ 4580 if (nx_cur) { 4581 xfrm_states_put(x_cur, nx_cur); 4582 xfrm_states_delete(x_cur, nx_cur); 4583 } 4584 4585 /* Stage 5 - announce */ 4586 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4587 4588 xfrm_pol_put(pol); 4589 4590 return 0; 4591 out: 4592 return err; 4593 4594 restore_state: 4595 if (pol) 4596 xfrm_pol_put(pol); 4597 if (nx_cur) 4598 xfrm_states_put(x_cur, nx_cur); 4599 if (nx_new) 4600 xfrm_states_delete(x_new, nx_new); 4601 4602 return err; 4603 } 4604 EXPORT_SYMBOL(xfrm_migrate); 4605 #endif 4606