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