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 return ret; 1907 } 1908 1909 static struct xfrm_pol_inexact_node * 1910 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1911 seqcount_spinlock_t *count, 1912 const xfrm_address_t *addr, u16 family) 1913 { 1914 const struct rb_node *parent; 1915 int seq; 1916 1917 again: 1918 seq = read_seqcount_begin(count); 1919 1920 parent = rcu_dereference_raw(r->rb_node); 1921 while (parent) { 1922 struct xfrm_pol_inexact_node *node; 1923 int delta; 1924 1925 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1926 1927 delta = xfrm_policy_addr_delta(addr, &node->addr, 1928 node->prefixlen, family); 1929 if (delta < 0) { 1930 parent = rcu_dereference_raw(parent->rb_left); 1931 continue; 1932 } else if (delta > 0) { 1933 parent = rcu_dereference_raw(parent->rb_right); 1934 continue; 1935 } 1936 1937 return node; 1938 } 1939 1940 if (read_seqcount_retry(count, seq)) 1941 goto again; 1942 1943 return NULL; 1944 } 1945 1946 static bool 1947 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1948 struct xfrm_pol_inexact_bin *b, 1949 const xfrm_address_t *saddr, 1950 const xfrm_address_t *daddr) 1951 { 1952 struct xfrm_pol_inexact_node *n; 1953 u16 family; 1954 1955 if (!b) 1956 return false; 1957 1958 family = b->k.family; 1959 memset(cand, 0, sizeof(*cand)); 1960 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1961 1962 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1963 family); 1964 if (n) { 1965 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1966 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1967 family); 1968 if (n) 1969 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1970 } 1971 1972 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1973 family); 1974 if (n) 1975 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1976 1977 return true; 1978 } 1979 1980 static struct xfrm_pol_inexact_bin * 1981 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1982 u8 dir, u32 if_id) 1983 { 1984 struct xfrm_pol_inexact_key k = { 1985 .family = family, 1986 .type = type, 1987 .dir = dir, 1988 .if_id = if_id, 1989 }; 1990 1991 write_pnet(&k.net, net); 1992 1993 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1994 xfrm_pol_inexact_params); 1995 } 1996 1997 static struct xfrm_pol_inexact_bin * 1998 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 1999 u8 dir, u32 if_id) 2000 { 2001 struct xfrm_pol_inexact_bin *bin; 2002 2003 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2004 2005 rcu_read_lock(); 2006 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2007 rcu_read_unlock(); 2008 2009 return bin; 2010 } 2011 2012 static struct xfrm_policy * 2013 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2014 struct xfrm_policy *prefer, 2015 const struct flowi *fl, 2016 u8 type, u16 family, int dir, u32 if_id) 2017 { 2018 u32 priority = prefer ? prefer->priority : ~0u; 2019 struct xfrm_policy *pol; 2020 2021 if (!chain) 2022 return NULL; 2023 2024 hlist_for_each_entry_rcu(pol, chain, bydst) { 2025 int err; 2026 2027 if (pol->priority > priority) 2028 break; 2029 2030 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2031 if (err) { 2032 if (err != -ESRCH) 2033 return ERR_PTR(err); 2034 2035 continue; 2036 } 2037 2038 if (prefer) { 2039 /* matches. Is it older than *prefer? */ 2040 if (pol->priority == priority && 2041 prefer->pos < pol->pos) 2042 return prefer; 2043 } 2044 2045 return pol; 2046 } 2047 2048 return NULL; 2049 } 2050 2051 static struct xfrm_policy * 2052 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2053 struct xfrm_policy *prefer, 2054 const struct flowi *fl, 2055 u8 type, u16 family, int dir, u32 if_id) 2056 { 2057 struct xfrm_policy *tmp; 2058 int i; 2059 2060 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2061 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2062 prefer, 2063 fl, type, family, dir, 2064 if_id); 2065 if (!tmp) 2066 continue; 2067 2068 if (IS_ERR(tmp)) 2069 return tmp; 2070 prefer = tmp; 2071 } 2072 2073 return prefer; 2074 } 2075 2076 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2077 const struct flowi *fl, 2078 u16 family, u8 dir, 2079 u32 if_id) 2080 { 2081 struct xfrm_pol_inexact_candidates cand; 2082 const xfrm_address_t *daddr, *saddr; 2083 struct xfrm_pol_inexact_bin *bin; 2084 struct xfrm_policy *pol, *ret; 2085 struct hlist_head *chain; 2086 unsigned int sequence; 2087 int err; 2088 2089 daddr = xfrm_flowi_daddr(fl, family); 2090 saddr = xfrm_flowi_saddr(fl, family); 2091 if (unlikely(!daddr || !saddr)) 2092 return NULL; 2093 2094 retry: 2095 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 2096 rcu_read_lock(); 2097 2098 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2099 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) { 2100 rcu_read_unlock(); 2101 goto retry; 2102 } 2103 2104 ret = NULL; 2105 hlist_for_each_entry_rcu(pol, chain, bydst) { 2106 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2107 if (err) { 2108 if (err == -ESRCH) 2109 continue; 2110 else { 2111 ret = ERR_PTR(err); 2112 goto fail; 2113 } 2114 } else { 2115 ret = pol; 2116 break; 2117 } 2118 } 2119 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2120 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2121 daddr)) 2122 goto skip_inexact; 2123 2124 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2125 family, dir, if_id); 2126 if (pol) { 2127 ret = pol; 2128 if (IS_ERR(pol)) 2129 goto fail; 2130 } 2131 2132 skip_inexact: 2133 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) { 2134 rcu_read_unlock(); 2135 goto retry; 2136 } 2137 2138 if (ret && !xfrm_pol_hold_rcu(ret)) { 2139 rcu_read_unlock(); 2140 goto retry; 2141 } 2142 fail: 2143 rcu_read_unlock(); 2144 2145 return ret; 2146 } 2147 2148 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2149 const struct flowi *fl, 2150 u16 family, u8 dir, u32 if_id) 2151 { 2152 #ifdef CONFIG_XFRM_SUB_POLICY 2153 struct xfrm_policy *pol; 2154 2155 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2156 dir, if_id); 2157 if (pol != NULL) 2158 return pol; 2159 #endif 2160 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2161 dir, if_id); 2162 } 2163 2164 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2165 const struct flowi *fl, 2166 u16 family, u32 if_id) 2167 { 2168 struct xfrm_policy *pol; 2169 2170 rcu_read_lock(); 2171 again: 2172 pol = rcu_dereference(sk->sk_policy[dir]); 2173 if (pol != NULL) { 2174 bool match; 2175 int err = 0; 2176 2177 if (pol->family != family) { 2178 pol = NULL; 2179 goto out; 2180 } 2181 2182 match = xfrm_selector_match(&pol->selector, fl, family); 2183 if (match) { 2184 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2185 pol->if_id != if_id) { 2186 pol = NULL; 2187 goto out; 2188 } 2189 err = security_xfrm_policy_lookup(pol->security, 2190 fl->flowi_secid); 2191 if (!err) { 2192 if (!xfrm_pol_hold_rcu(pol)) 2193 goto again; 2194 } else if (err == -ESRCH) { 2195 pol = NULL; 2196 } else { 2197 pol = ERR_PTR(err); 2198 } 2199 } else 2200 pol = NULL; 2201 } 2202 out: 2203 rcu_read_unlock(); 2204 return pol; 2205 } 2206 2207 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2208 { 2209 struct net *net = xp_net(pol); 2210 2211 list_add(&pol->walk.all, &net->xfrm.policy_all); 2212 net->xfrm.policy_count[dir]++; 2213 xfrm_pol_hold(pol); 2214 } 2215 2216 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2217 int dir) 2218 { 2219 struct net *net = xp_net(pol); 2220 2221 if (list_empty(&pol->walk.all)) 2222 return NULL; 2223 2224 /* Socket policies are not hashed. */ 2225 if (!hlist_unhashed(&pol->bydst)) { 2226 hlist_del_rcu(&pol->bydst); 2227 hlist_del_init(&pol->bydst_inexact_list); 2228 hlist_del(&pol->byidx); 2229 } 2230 2231 list_del_init(&pol->walk.all); 2232 net->xfrm.policy_count[dir]--; 2233 2234 return pol; 2235 } 2236 2237 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2238 { 2239 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2240 } 2241 2242 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2243 { 2244 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2245 } 2246 2247 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2248 { 2249 struct net *net = xp_net(pol); 2250 2251 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2252 pol = __xfrm_policy_unlink(pol, dir); 2253 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2254 if (pol) { 2255 xfrm_policy_kill(pol); 2256 return 0; 2257 } 2258 return -ENOENT; 2259 } 2260 EXPORT_SYMBOL(xfrm_policy_delete); 2261 2262 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2263 { 2264 struct net *net = sock_net(sk); 2265 struct xfrm_policy *old_pol; 2266 2267 #ifdef CONFIG_XFRM_SUB_POLICY 2268 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2269 return -EINVAL; 2270 #endif 2271 2272 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2273 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2274 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2275 if (pol) { 2276 pol->curlft.add_time = ktime_get_real_seconds(); 2277 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2278 xfrm_sk_policy_link(pol, dir); 2279 } 2280 rcu_assign_pointer(sk->sk_policy[dir], pol); 2281 if (old_pol) { 2282 if (pol) 2283 xfrm_policy_requeue(old_pol, pol); 2284 2285 /* Unlinking succeeds always. This is the only function 2286 * allowed to delete or replace socket policy. 2287 */ 2288 xfrm_sk_policy_unlink(old_pol, dir); 2289 } 2290 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2291 2292 if (old_pol) { 2293 xfrm_policy_kill(old_pol); 2294 } 2295 return 0; 2296 } 2297 2298 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2299 { 2300 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2301 struct net *net = xp_net(old); 2302 2303 if (newp) { 2304 newp->selector = old->selector; 2305 if (security_xfrm_policy_clone(old->security, 2306 &newp->security)) { 2307 kfree(newp); 2308 return NULL; /* ENOMEM */ 2309 } 2310 newp->lft = old->lft; 2311 newp->curlft = old->curlft; 2312 newp->mark = old->mark; 2313 newp->if_id = old->if_id; 2314 newp->action = old->action; 2315 newp->flags = old->flags; 2316 newp->xfrm_nr = old->xfrm_nr; 2317 newp->index = old->index; 2318 newp->type = old->type; 2319 newp->family = old->family; 2320 memcpy(newp->xfrm_vec, old->xfrm_vec, 2321 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2322 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2323 xfrm_sk_policy_link(newp, dir); 2324 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2325 xfrm_pol_put(newp); 2326 } 2327 return newp; 2328 } 2329 2330 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2331 { 2332 const struct xfrm_policy *p; 2333 struct xfrm_policy *np; 2334 int i, ret = 0; 2335 2336 rcu_read_lock(); 2337 for (i = 0; i < 2; i++) { 2338 p = rcu_dereference(osk->sk_policy[i]); 2339 if (p) { 2340 np = clone_policy(p, i); 2341 if (unlikely(!np)) { 2342 ret = -ENOMEM; 2343 break; 2344 } 2345 rcu_assign_pointer(sk->sk_policy[i], np); 2346 } 2347 } 2348 rcu_read_unlock(); 2349 return ret; 2350 } 2351 2352 static int 2353 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2354 xfrm_address_t *remote, unsigned short family, u32 mark) 2355 { 2356 int err; 2357 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2358 2359 if (unlikely(afinfo == NULL)) 2360 return -EINVAL; 2361 err = afinfo->get_saddr(net, oif, local, remote, mark); 2362 rcu_read_unlock(); 2363 return err; 2364 } 2365 2366 /* Resolve list of templates for the flow, given policy. */ 2367 2368 static int 2369 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2370 struct xfrm_state **xfrm, unsigned short family) 2371 { 2372 struct net *net = xp_net(policy); 2373 int nx; 2374 int i, error; 2375 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2376 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2377 xfrm_address_t tmp; 2378 2379 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2380 struct xfrm_state *x; 2381 xfrm_address_t *remote = daddr; 2382 xfrm_address_t *local = saddr; 2383 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2384 2385 if (tmpl->mode == XFRM_MODE_TUNNEL || 2386 tmpl->mode == XFRM_MODE_BEET) { 2387 remote = &tmpl->id.daddr; 2388 local = &tmpl->saddr; 2389 if (xfrm_addr_any(local, tmpl->encap_family)) { 2390 error = xfrm_get_saddr(net, fl->flowi_oif, 2391 &tmp, remote, 2392 tmpl->encap_family, 0); 2393 if (error) 2394 goto fail; 2395 local = &tmp; 2396 } 2397 } 2398 2399 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2400 family, policy->if_id); 2401 2402 if (x && x->km.state == XFRM_STATE_VALID) { 2403 xfrm[nx++] = x; 2404 daddr = remote; 2405 saddr = local; 2406 continue; 2407 } 2408 if (x) { 2409 error = (x->km.state == XFRM_STATE_ERROR ? 2410 -EINVAL : -EAGAIN); 2411 xfrm_state_put(x); 2412 } else if (error == -ESRCH) { 2413 error = -EAGAIN; 2414 } 2415 2416 if (!tmpl->optional) 2417 goto fail; 2418 } 2419 return nx; 2420 2421 fail: 2422 for (nx--; nx >= 0; nx--) 2423 xfrm_state_put(xfrm[nx]); 2424 return error; 2425 } 2426 2427 static int 2428 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2429 struct xfrm_state **xfrm, unsigned short family) 2430 { 2431 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2432 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2433 int cnx = 0; 2434 int error; 2435 int ret; 2436 int i; 2437 2438 for (i = 0; i < npols; i++) { 2439 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2440 error = -ENOBUFS; 2441 goto fail; 2442 } 2443 2444 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2445 if (ret < 0) { 2446 error = ret; 2447 goto fail; 2448 } else 2449 cnx += ret; 2450 } 2451 2452 /* found states are sorted for outbound processing */ 2453 if (npols > 1) 2454 xfrm_state_sort(xfrm, tpp, cnx, family); 2455 2456 return cnx; 2457 2458 fail: 2459 for (cnx--; cnx >= 0; cnx--) 2460 xfrm_state_put(tpp[cnx]); 2461 return error; 2462 2463 } 2464 2465 static int xfrm_get_tos(const struct flowi *fl, int family) 2466 { 2467 if (family == AF_INET) 2468 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2469 2470 return 0; 2471 } 2472 2473 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2474 { 2475 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2476 struct dst_ops *dst_ops; 2477 struct xfrm_dst *xdst; 2478 2479 if (!afinfo) 2480 return ERR_PTR(-EINVAL); 2481 2482 switch (family) { 2483 case AF_INET: 2484 dst_ops = &net->xfrm.xfrm4_dst_ops; 2485 break; 2486 #if IS_ENABLED(CONFIG_IPV6) 2487 case AF_INET6: 2488 dst_ops = &net->xfrm.xfrm6_dst_ops; 2489 break; 2490 #endif 2491 default: 2492 BUG(); 2493 } 2494 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2495 2496 if (likely(xdst)) { 2497 struct dst_entry *dst = &xdst->u.dst; 2498 2499 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 2500 } else 2501 xdst = ERR_PTR(-ENOBUFS); 2502 2503 rcu_read_unlock(); 2504 2505 return xdst; 2506 } 2507 2508 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2509 int nfheader_len) 2510 { 2511 if (dst->ops->family == AF_INET6) { 2512 struct rt6_info *rt = (struct rt6_info *)dst; 2513 path->path_cookie = rt6_get_cookie(rt); 2514 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2515 } 2516 } 2517 2518 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2519 const struct flowi *fl) 2520 { 2521 const struct xfrm_policy_afinfo *afinfo = 2522 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2523 int err; 2524 2525 if (!afinfo) 2526 return -EINVAL; 2527 2528 err = afinfo->fill_dst(xdst, dev, fl); 2529 2530 rcu_read_unlock(); 2531 2532 return err; 2533 } 2534 2535 2536 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2537 * all the metrics... Shortly, bundle a bundle. 2538 */ 2539 2540 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2541 struct xfrm_state **xfrm, 2542 struct xfrm_dst **bundle, 2543 int nx, 2544 const struct flowi *fl, 2545 struct dst_entry *dst) 2546 { 2547 const struct xfrm_state_afinfo *afinfo; 2548 const struct xfrm_mode *inner_mode; 2549 struct net *net = xp_net(policy); 2550 unsigned long now = jiffies; 2551 struct net_device *dev; 2552 struct xfrm_dst *xdst_prev = NULL; 2553 struct xfrm_dst *xdst0 = NULL; 2554 int i = 0; 2555 int err; 2556 int header_len = 0; 2557 int nfheader_len = 0; 2558 int trailer_len = 0; 2559 int tos; 2560 int family = policy->selector.family; 2561 xfrm_address_t saddr, daddr; 2562 2563 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2564 2565 tos = xfrm_get_tos(fl, family); 2566 2567 dst_hold(dst); 2568 2569 for (; i < nx; i++) { 2570 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2571 struct dst_entry *dst1 = &xdst->u.dst; 2572 2573 err = PTR_ERR(xdst); 2574 if (IS_ERR(xdst)) { 2575 dst_release(dst); 2576 goto put_states; 2577 } 2578 2579 bundle[i] = xdst; 2580 if (!xdst_prev) 2581 xdst0 = xdst; 2582 else 2583 /* Ref count is taken during xfrm_alloc_dst() 2584 * No need to do dst_clone() on dst1 2585 */ 2586 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2587 2588 if (xfrm[i]->sel.family == AF_UNSPEC) { 2589 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2590 xfrm_af2proto(family)); 2591 if (!inner_mode) { 2592 err = -EAFNOSUPPORT; 2593 dst_release(dst); 2594 goto put_states; 2595 } 2596 } else 2597 inner_mode = &xfrm[i]->inner_mode; 2598 2599 xdst->route = dst; 2600 dst_copy_metrics(dst1, dst); 2601 2602 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2603 __u32 mark = 0; 2604 2605 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2606 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2607 2608 family = xfrm[i]->props.family; 2609 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 2610 &saddr, &daddr, family, mark); 2611 err = PTR_ERR(dst); 2612 if (IS_ERR(dst)) 2613 goto put_states; 2614 } else 2615 dst_hold(dst); 2616 2617 dst1->xfrm = xfrm[i]; 2618 xdst->xfrm_genid = xfrm[i]->genid; 2619 2620 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2621 dst1->lastuse = now; 2622 2623 dst1->input = dst_discard; 2624 2625 rcu_read_lock(); 2626 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2627 if (likely(afinfo)) 2628 dst1->output = afinfo->output; 2629 else 2630 dst1->output = dst_discard_out; 2631 rcu_read_unlock(); 2632 2633 xdst_prev = xdst; 2634 2635 header_len += xfrm[i]->props.header_len; 2636 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2637 nfheader_len += xfrm[i]->props.header_len; 2638 trailer_len += xfrm[i]->props.trailer_len; 2639 } 2640 2641 xfrm_dst_set_child(xdst_prev, dst); 2642 xdst0->path = dst; 2643 2644 err = -ENODEV; 2645 dev = dst->dev; 2646 if (!dev) 2647 goto free_dst; 2648 2649 xfrm_init_path(xdst0, dst, nfheader_len); 2650 xfrm_init_pmtu(bundle, nx); 2651 2652 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2653 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2654 err = xfrm_fill_dst(xdst_prev, dev, fl); 2655 if (err) 2656 goto free_dst; 2657 2658 xdst_prev->u.dst.header_len = header_len; 2659 xdst_prev->u.dst.trailer_len = trailer_len; 2660 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2661 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2662 } 2663 2664 return &xdst0->u.dst; 2665 2666 put_states: 2667 for (; i < nx; i++) 2668 xfrm_state_put(xfrm[i]); 2669 free_dst: 2670 if (xdst0) 2671 dst_release_immediate(&xdst0->u.dst); 2672 2673 return ERR_PTR(err); 2674 } 2675 2676 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2677 struct xfrm_policy **pols, 2678 int *num_pols, int *num_xfrms) 2679 { 2680 int i; 2681 2682 if (*num_pols == 0 || !pols[0]) { 2683 *num_pols = 0; 2684 *num_xfrms = 0; 2685 return 0; 2686 } 2687 if (IS_ERR(pols[0])) 2688 return PTR_ERR(pols[0]); 2689 2690 *num_xfrms = pols[0]->xfrm_nr; 2691 2692 #ifdef CONFIG_XFRM_SUB_POLICY 2693 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 2694 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2695 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2696 XFRM_POLICY_TYPE_MAIN, 2697 fl, family, 2698 XFRM_POLICY_OUT, 2699 pols[0]->if_id); 2700 if (pols[1]) { 2701 if (IS_ERR(pols[1])) { 2702 xfrm_pols_put(pols, *num_pols); 2703 return PTR_ERR(pols[1]); 2704 } 2705 (*num_pols)++; 2706 (*num_xfrms) += pols[1]->xfrm_nr; 2707 } 2708 } 2709 #endif 2710 for (i = 0; i < *num_pols; i++) { 2711 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2712 *num_xfrms = -1; 2713 break; 2714 } 2715 } 2716 2717 return 0; 2718 2719 } 2720 2721 static struct xfrm_dst * 2722 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2723 const struct flowi *fl, u16 family, 2724 struct dst_entry *dst_orig) 2725 { 2726 struct net *net = xp_net(pols[0]); 2727 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2728 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2729 struct xfrm_dst *xdst; 2730 struct dst_entry *dst; 2731 int err; 2732 2733 /* Try to instantiate a bundle */ 2734 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2735 if (err <= 0) { 2736 if (err == 0) 2737 return NULL; 2738 2739 if (err != -EAGAIN) 2740 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2741 return ERR_PTR(err); 2742 } 2743 2744 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2745 if (IS_ERR(dst)) { 2746 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2747 return ERR_CAST(dst); 2748 } 2749 2750 xdst = (struct xfrm_dst *)dst; 2751 xdst->num_xfrms = err; 2752 xdst->num_pols = num_pols; 2753 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2754 xdst->policy_genid = atomic_read(&pols[0]->genid); 2755 2756 return xdst; 2757 } 2758 2759 static void xfrm_policy_queue_process(struct timer_list *t) 2760 { 2761 struct sk_buff *skb; 2762 struct sock *sk; 2763 struct dst_entry *dst; 2764 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2765 struct net *net = xp_net(pol); 2766 struct xfrm_policy_queue *pq = &pol->polq; 2767 struct flowi fl; 2768 struct sk_buff_head list; 2769 __u32 skb_mark; 2770 2771 spin_lock(&pq->hold_queue.lock); 2772 skb = skb_peek(&pq->hold_queue); 2773 if (!skb) { 2774 spin_unlock(&pq->hold_queue.lock); 2775 goto out; 2776 } 2777 dst = skb_dst(skb); 2778 sk = skb->sk; 2779 2780 /* Fixup the mark to support VTI. */ 2781 skb_mark = skb->mark; 2782 skb->mark = pol->mark.v; 2783 xfrm_decode_session(skb, &fl, dst->ops->family); 2784 skb->mark = skb_mark; 2785 spin_unlock(&pq->hold_queue.lock); 2786 2787 dst_hold(xfrm_dst_path(dst)); 2788 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2789 if (IS_ERR(dst)) 2790 goto purge_queue; 2791 2792 if (dst->flags & DST_XFRM_QUEUE) { 2793 dst_release(dst); 2794 2795 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2796 goto purge_queue; 2797 2798 pq->timeout = pq->timeout << 1; 2799 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2800 xfrm_pol_hold(pol); 2801 goto out; 2802 } 2803 2804 dst_release(dst); 2805 2806 __skb_queue_head_init(&list); 2807 2808 spin_lock(&pq->hold_queue.lock); 2809 pq->timeout = 0; 2810 skb_queue_splice_init(&pq->hold_queue, &list); 2811 spin_unlock(&pq->hold_queue.lock); 2812 2813 while (!skb_queue_empty(&list)) { 2814 skb = __skb_dequeue(&list); 2815 2816 /* Fixup the mark to support VTI. */ 2817 skb_mark = skb->mark; 2818 skb->mark = pol->mark.v; 2819 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2820 skb->mark = skb_mark; 2821 2822 dst_hold(xfrm_dst_path(skb_dst(skb))); 2823 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2824 if (IS_ERR(dst)) { 2825 kfree_skb(skb); 2826 continue; 2827 } 2828 2829 nf_reset_ct(skb); 2830 skb_dst_drop(skb); 2831 skb_dst_set(skb, dst); 2832 2833 dst_output(net, skb->sk, skb); 2834 } 2835 2836 out: 2837 xfrm_pol_put(pol); 2838 return; 2839 2840 purge_queue: 2841 pq->timeout = 0; 2842 skb_queue_purge(&pq->hold_queue); 2843 xfrm_pol_put(pol); 2844 } 2845 2846 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2847 { 2848 unsigned long sched_next; 2849 struct dst_entry *dst = skb_dst(skb); 2850 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2851 struct xfrm_policy *pol = xdst->pols[0]; 2852 struct xfrm_policy_queue *pq = &pol->polq; 2853 2854 if (unlikely(skb_fclone_busy(sk, skb))) { 2855 kfree_skb(skb); 2856 return 0; 2857 } 2858 2859 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2860 kfree_skb(skb); 2861 return -EAGAIN; 2862 } 2863 2864 skb_dst_force(skb); 2865 2866 spin_lock_bh(&pq->hold_queue.lock); 2867 2868 if (!pq->timeout) 2869 pq->timeout = XFRM_QUEUE_TMO_MIN; 2870 2871 sched_next = jiffies + pq->timeout; 2872 2873 if (del_timer(&pq->hold_timer)) { 2874 if (time_before(pq->hold_timer.expires, sched_next)) 2875 sched_next = pq->hold_timer.expires; 2876 xfrm_pol_put(pol); 2877 } 2878 2879 __skb_queue_tail(&pq->hold_queue, skb); 2880 if (!mod_timer(&pq->hold_timer, sched_next)) 2881 xfrm_pol_hold(pol); 2882 2883 spin_unlock_bh(&pq->hold_queue.lock); 2884 2885 return 0; 2886 } 2887 2888 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2889 struct xfrm_flo *xflo, 2890 const struct flowi *fl, 2891 int num_xfrms, 2892 u16 family) 2893 { 2894 int err; 2895 struct net_device *dev; 2896 struct dst_entry *dst; 2897 struct dst_entry *dst1; 2898 struct xfrm_dst *xdst; 2899 2900 xdst = xfrm_alloc_dst(net, family); 2901 if (IS_ERR(xdst)) 2902 return xdst; 2903 2904 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2905 net->xfrm.sysctl_larval_drop || 2906 num_xfrms <= 0) 2907 return xdst; 2908 2909 dst = xflo->dst_orig; 2910 dst1 = &xdst->u.dst; 2911 dst_hold(dst); 2912 xdst->route = dst; 2913 2914 dst_copy_metrics(dst1, dst); 2915 2916 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2917 dst1->flags |= DST_XFRM_QUEUE; 2918 dst1->lastuse = jiffies; 2919 2920 dst1->input = dst_discard; 2921 dst1->output = xdst_queue_output; 2922 2923 dst_hold(dst); 2924 xfrm_dst_set_child(xdst, dst); 2925 xdst->path = dst; 2926 2927 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2928 2929 err = -ENODEV; 2930 dev = dst->dev; 2931 if (!dev) 2932 goto free_dst; 2933 2934 err = xfrm_fill_dst(xdst, dev, fl); 2935 if (err) 2936 goto free_dst; 2937 2938 out: 2939 return xdst; 2940 2941 free_dst: 2942 dst_release(dst1); 2943 xdst = ERR_PTR(err); 2944 goto out; 2945 } 2946 2947 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2948 const struct flowi *fl, 2949 u16 family, u8 dir, 2950 struct xfrm_flo *xflo, u32 if_id) 2951 { 2952 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2953 int num_pols = 0, num_xfrms = 0, err; 2954 struct xfrm_dst *xdst; 2955 2956 /* Resolve policies to use if we couldn't get them from 2957 * previous cache entry */ 2958 num_pols = 1; 2959 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2960 err = xfrm_expand_policies(fl, family, pols, 2961 &num_pols, &num_xfrms); 2962 if (err < 0) 2963 goto inc_error; 2964 if (num_pols == 0) 2965 return NULL; 2966 if (num_xfrms <= 0) 2967 goto make_dummy_bundle; 2968 2969 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2970 xflo->dst_orig); 2971 if (IS_ERR(xdst)) { 2972 err = PTR_ERR(xdst); 2973 if (err == -EREMOTE) { 2974 xfrm_pols_put(pols, num_pols); 2975 return NULL; 2976 } 2977 2978 if (err != -EAGAIN) 2979 goto error; 2980 goto make_dummy_bundle; 2981 } else if (xdst == NULL) { 2982 num_xfrms = 0; 2983 goto make_dummy_bundle; 2984 } 2985 2986 return xdst; 2987 2988 make_dummy_bundle: 2989 /* We found policies, but there's no bundles to instantiate: 2990 * either because the policy blocks, has no transformations or 2991 * we could not build template (no xfrm_states).*/ 2992 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2993 if (IS_ERR(xdst)) { 2994 xfrm_pols_put(pols, num_pols); 2995 return ERR_CAST(xdst); 2996 } 2997 xdst->num_pols = num_pols; 2998 xdst->num_xfrms = num_xfrms; 2999 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 3000 3001 return xdst; 3002 3003 inc_error: 3004 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 3005 error: 3006 xfrm_pols_put(pols, num_pols); 3007 return ERR_PTR(err); 3008 } 3009 3010 static struct dst_entry *make_blackhole(struct net *net, u16 family, 3011 struct dst_entry *dst_orig) 3012 { 3013 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 3014 struct dst_entry *ret; 3015 3016 if (!afinfo) { 3017 dst_release(dst_orig); 3018 return ERR_PTR(-EINVAL); 3019 } else { 3020 ret = afinfo->blackhole_route(net, dst_orig); 3021 } 3022 rcu_read_unlock(); 3023 3024 return ret; 3025 } 3026 3027 /* Finds/creates a bundle for given flow and if_id 3028 * 3029 * At the moment we eat a raw IP route. Mostly to speed up lookups 3030 * on interfaces with disabled IPsec. 3031 * 3032 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3033 * compatibility 3034 */ 3035 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3036 struct dst_entry *dst_orig, 3037 const struct flowi *fl, 3038 const struct sock *sk, 3039 int flags, u32 if_id) 3040 { 3041 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3042 struct xfrm_dst *xdst; 3043 struct dst_entry *dst, *route; 3044 u16 family = dst_orig->ops->family; 3045 u8 dir = XFRM_POLICY_OUT; 3046 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3047 3048 dst = NULL; 3049 xdst = NULL; 3050 route = NULL; 3051 3052 sk = sk_const_to_full_sk(sk); 3053 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3054 num_pols = 1; 3055 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3056 if_id); 3057 err = xfrm_expand_policies(fl, family, pols, 3058 &num_pols, &num_xfrms); 3059 if (err < 0) 3060 goto dropdst; 3061 3062 if (num_pols) { 3063 if (num_xfrms <= 0) { 3064 drop_pols = num_pols; 3065 goto no_transform; 3066 } 3067 3068 xdst = xfrm_resolve_and_create_bundle( 3069 pols, num_pols, fl, 3070 family, dst_orig); 3071 3072 if (IS_ERR(xdst)) { 3073 xfrm_pols_put(pols, num_pols); 3074 err = PTR_ERR(xdst); 3075 if (err == -EREMOTE) 3076 goto nopol; 3077 3078 goto dropdst; 3079 } else if (xdst == NULL) { 3080 num_xfrms = 0; 3081 drop_pols = num_pols; 3082 goto no_transform; 3083 } 3084 3085 route = xdst->route; 3086 } 3087 } 3088 3089 if (xdst == NULL) { 3090 struct xfrm_flo xflo; 3091 3092 xflo.dst_orig = dst_orig; 3093 xflo.flags = flags; 3094 3095 /* To accelerate a bit... */ 3096 if (!if_id && ((dst_orig->flags & DST_NOXFRM) || 3097 !net->xfrm.policy_count[XFRM_POLICY_OUT])) 3098 goto nopol; 3099 3100 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3101 if (xdst == NULL) 3102 goto nopol; 3103 if (IS_ERR(xdst)) { 3104 err = PTR_ERR(xdst); 3105 goto dropdst; 3106 } 3107 3108 num_pols = xdst->num_pols; 3109 num_xfrms = xdst->num_xfrms; 3110 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3111 route = xdst->route; 3112 } 3113 3114 dst = &xdst->u.dst; 3115 if (route == NULL && num_xfrms > 0) { 3116 /* The only case when xfrm_bundle_lookup() returns a 3117 * bundle with null route, is when the template could 3118 * not be resolved. It means policies are there, but 3119 * bundle could not be created, since we don't yet 3120 * have the xfrm_state's. We need to wait for KM to 3121 * negotiate new SA's or bail out with error.*/ 3122 if (net->xfrm.sysctl_larval_drop) { 3123 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3124 err = -EREMOTE; 3125 goto error; 3126 } 3127 3128 err = -EAGAIN; 3129 3130 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3131 goto error; 3132 } 3133 3134 no_transform: 3135 if (num_pols == 0) 3136 goto nopol; 3137 3138 if ((flags & XFRM_LOOKUP_ICMP) && 3139 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3140 err = -ENOENT; 3141 goto error; 3142 } 3143 3144 for (i = 0; i < num_pols; i++) 3145 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3146 3147 if (num_xfrms < 0) { 3148 /* Prohibit the flow */ 3149 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3150 err = -EPERM; 3151 goto error; 3152 } else if (num_xfrms > 0) { 3153 /* Flow transformed */ 3154 dst_release(dst_orig); 3155 } else { 3156 /* Flow passes untransformed */ 3157 dst_release(dst); 3158 dst = dst_orig; 3159 } 3160 ok: 3161 xfrm_pols_put(pols, drop_pols); 3162 if (dst && dst->xfrm && 3163 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3164 dst->flags |= DST_XFRM_TUNNEL; 3165 return dst; 3166 3167 nopol: 3168 if (!(flags & XFRM_LOOKUP_ICMP)) { 3169 dst = dst_orig; 3170 goto ok; 3171 } 3172 err = -ENOENT; 3173 error: 3174 dst_release(dst); 3175 dropdst: 3176 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3177 dst_release(dst_orig); 3178 xfrm_pols_put(pols, drop_pols); 3179 return ERR_PTR(err); 3180 } 3181 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3182 3183 /* Main function: finds/creates a bundle for given flow. 3184 * 3185 * At the moment we eat a raw IP route. Mostly to speed up lookups 3186 * on interfaces with disabled IPsec. 3187 */ 3188 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3189 const struct flowi *fl, const struct sock *sk, 3190 int flags) 3191 { 3192 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3193 } 3194 EXPORT_SYMBOL(xfrm_lookup); 3195 3196 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3197 * Otherwise we may send out blackholed packets. 3198 */ 3199 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3200 const struct flowi *fl, 3201 const struct sock *sk, int flags) 3202 { 3203 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3204 flags | XFRM_LOOKUP_QUEUE | 3205 XFRM_LOOKUP_KEEP_DST_REF); 3206 3207 if (PTR_ERR(dst) == -EREMOTE) 3208 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3209 3210 if (IS_ERR(dst)) 3211 dst_release(dst_orig); 3212 3213 return dst; 3214 } 3215 EXPORT_SYMBOL(xfrm_lookup_route); 3216 3217 static inline int 3218 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3219 { 3220 struct sec_path *sp = skb_sec_path(skb); 3221 struct xfrm_state *x; 3222 3223 if (!sp || idx < 0 || idx >= sp->len) 3224 return 0; 3225 x = sp->xvec[idx]; 3226 if (!x->type->reject) 3227 return 0; 3228 return x->type->reject(x, skb, fl); 3229 } 3230 3231 /* When skb is transformed back to its "native" form, we have to 3232 * check policy restrictions. At the moment we make this in maximally 3233 * stupid way. Shame on me. :-) Of course, connected sockets must 3234 * have policy cached at them. 3235 */ 3236 3237 static inline int 3238 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3239 unsigned short family) 3240 { 3241 if (xfrm_state_kern(x)) 3242 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3243 return x->id.proto == tmpl->id.proto && 3244 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3245 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3246 x->props.mode == tmpl->mode && 3247 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3248 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3249 !(x->props.mode != XFRM_MODE_TRANSPORT && 3250 xfrm_state_addr_cmp(tmpl, x, family)); 3251 } 3252 3253 /* 3254 * 0 or more than 0 is returned when validation is succeeded (either bypass 3255 * because of optional transport mode, or next index of the matched secpath 3256 * state with the template. 3257 * -1 is returned when no matching template is found. 3258 * Otherwise "-2 - errored_index" is returned. 3259 */ 3260 static inline int 3261 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3262 unsigned short family) 3263 { 3264 int idx = start; 3265 3266 if (tmpl->optional) { 3267 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3268 return start; 3269 } else 3270 start = -1; 3271 for (; idx < sp->len; idx++) { 3272 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3273 return ++idx; 3274 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3275 if (start == -1) 3276 start = -2-idx; 3277 break; 3278 } 3279 } 3280 return start; 3281 } 3282 3283 static void 3284 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3285 { 3286 const struct iphdr *iph = ip_hdr(skb); 3287 int ihl = iph->ihl; 3288 u8 *xprth = skb_network_header(skb) + ihl * 4; 3289 struct flowi4 *fl4 = &fl->u.ip4; 3290 int oif = 0; 3291 3292 if (skb_dst(skb) && skb_dst(skb)->dev) 3293 oif = skb_dst(skb)->dev->ifindex; 3294 3295 memset(fl4, 0, sizeof(struct flowi4)); 3296 fl4->flowi4_mark = skb->mark; 3297 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3298 3299 fl4->flowi4_proto = iph->protocol; 3300 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3301 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3302 fl4->flowi4_tos = iph->tos; 3303 3304 if (!ip_is_fragment(iph)) { 3305 switch (iph->protocol) { 3306 case IPPROTO_UDP: 3307 case IPPROTO_UDPLITE: 3308 case IPPROTO_TCP: 3309 case IPPROTO_SCTP: 3310 case IPPROTO_DCCP: 3311 if (xprth + 4 < skb->data || 3312 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3313 __be16 *ports; 3314 3315 xprth = skb_network_header(skb) + ihl * 4; 3316 ports = (__be16 *)xprth; 3317 3318 fl4->fl4_sport = ports[!!reverse]; 3319 fl4->fl4_dport = ports[!reverse]; 3320 } 3321 break; 3322 case IPPROTO_ICMP: 3323 if (xprth + 2 < skb->data || 3324 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3325 u8 *icmp; 3326 3327 xprth = skb_network_header(skb) + ihl * 4; 3328 icmp = xprth; 3329 3330 fl4->fl4_icmp_type = icmp[0]; 3331 fl4->fl4_icmp_code = icmp[1]; 3332 } 3333 break; 3334 case IPPROTO_GRE: 3335 if (xprth + 12 < skb->data || 3336 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3337 __be16 *greflags; 3338 __be32 *gre_hdr; 3339 3340 xprth = skb_network_header(skb) + ihl * 4; 3341 greflags = (__be16 *)xprth; 3342 gre_hdr = (__be32 *)xprth; 3343 3344 if (greflags[0] & GRE_KEY) { 3345 if (greflags[0] & GRE_CSUM) 3346 gre_hdr++; 3347 fl4->fl4_gre_key = gre_hdr[1]; 3348 } 3349 } 3350 break; 3351 default: 3352 break; 3353 } 3354 } 3355 } 3356 3357 #if IS_ENABLED(CONFIG_IPV6) 3358 static void 3359 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3360 { 3361 struct flowi6 *fl6 = &fl->u.ip6; 3362 int onlyproto = 0; 3363 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3364 u32 offset = sizeof(*hdr); 3365 struct ipv6_opt_hdr *exthdr; 3366 const unsigned char *nh = skb_network_header(skb); 3367 u16 nhoff = IP6CB(skb)->nhoff; 3368 int oif = 0; 3369 u8 nexthdr; 3370 3371 if (!nhoff) 3372 nhoff = offsetof(struct ipv6hdr, nexthdr); 3373 3374 nexthdr = nh[nhoff]; 3375 3376 if (skb_dst(skb) && skb_dst(skb)->dev) 3377 oif = skb_dst(skb)->dev->ifindex; 3378 3379 memset(fl6, 0, sizeof(struct flowi6)); 3380 fl6->flowi6_mark = skb->mark; 3381 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3382 3383 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3384 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3385 3386 while (nh + offset + sizeof(*exthdr) < skb->data || 3387 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3388 nh = skb_network_header(skb); 3389 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3390 3391 switch (nexthdr) { 3392 case NEXTHDR_FRAGMENT: 3393 onlyproto = 1; 3394 fallthrough; 3395 case NEXTHDR_ROUTING: 3396 case NEXTHDR_HOP: 3397 case NEXTHDR_DEST: 3398 offset += ipv6_optlen(exthdr); 3399 nexthdr = exthdr->nexthdr; 3400 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3401 break; 3402 case IPPROTO_UDP: 3403 case IPPROTO_UDPLITE: 3404 case IPPROTO_TCP: 3405 case IPPROTO_SCTP: 3406 case IPPROTO_DCCP: 3407 if (!onlyproto && (nh + offset + 4 < skb->data || 3408 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3409 __be16 *ports; 3410 3411 nh = skb_network_header(skb); 3412 ports = (__be16 *)(nh + offset); 3413 fl6->fl6_sport = ports[!!reverse]; 3414 fl6->fl6_dport = ports[!reverse]; 3415 } 3416 fl6->flowi6_proto = nexthdr; 3417 return; 3418 case IPPROTO_ICMPV6: 3419 if (!onlyproto && (nh + offset + 2 < skb->data || 3420 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3421 u8 *icmp; 3422 3423 nh = skb_network_header(skb); 3424 icmp = (u8 *)(nh + offset); 3425 fl6->fl6_icmp_type = icmp[0]; 3426 fl6->fl6_icmp_code = icmp[1]; 3427 } 3428 fl6->flowi6_proto = nexthdr; 3429 return; 3430 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3431 case IPPROTO_MH: 3432 offset += ipv6_optlen(exthdr); 3433 if (!onlyproto && (nh + offset + 3 < skb->data || 3434 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3435 struct ip6_mh *mh; 3436 3437 nh = skb_network_header(skb); 3438 mh = (struct ip6_mh *)(nh + offset); 3439 fl6->fl6_mh_type = mh->ip6mh_type; 3440 } 3441 fl6->flowi6_proto = nexthdr; 3442 return; 3443 #endif 3444 default: 3445 fl6->flowi6_proto = nexthdr; 3446 return; 3447 } 3448 } 3449 } 3450 #endif 3451 3452 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3453 unsigned int family, int reverse) 3454 { 3455 switch (family) { 3456 case AF_INET: 3457 decode_session4(skb, fl, reverse); 3458 break; 3459 #if IS_ENABLED(CONFIG_IPV6) 3460 case AF_INET6: 3461 decode_session6(skb, fl, reverse); 3462 break; 3463 #endif 3464 default: 3465 return -EAFNOSUPPORT; 3466 } 3467 3468 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3469 } 3470 EXPORT_SYMBOL(__xfrm_decode_session); 3471 3472 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3473 { 3474 for (; k < sp->len; k++) { 3475 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3476 *idxp = k; 3477 return 1; 3478 } 3479 } 3480 3481 return 0; 3482 } 3483 3484 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3485 unsigned short family) 3486 { 3487 struct net *net = dev_net(skb->dev); 3488 struct xfrm_policy *pol; 3489 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3490 int npols = 0; 3491 int xfrm_nr; 3492 int pi; 3493 int reverse; 3494 struct flowi fl; 3495 int xerr_idx = -1; 3496 const struct xfrm_if_cb *ifcb; 3497 struct sec_path *sp; 3498 struct xfrm_if *xi; 3499 u32 if_id = 0; 3500 3501 rcu_read_lock(); 3502 ifcb = xfrm_if_get_cb(); 3503 3504 if (ifcb) { 3505 xi = ifcb->decode_session(skb, family); 3506 if (xi) { 3507 if_id = xi->p.if_id; 3508 net = xi->net; 3509 } 3510 } 3511 rcu_read_unlock(); 3512 3513 reverse = dir & ~XFRM_POLICY_MASK; 3514 dir &= XFRM_POLICY_MASK; 3515 3516 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3517 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3518 return 0; 3519 } 3520 3521 nf_nat_decode_session(skb, &fl, family); 3522 3523 /* First, check used SA against their selectors. */ 3524 sp = skb_sec_path(skb); 3525 if (sp) { 3526 int i; 3527 3528 for (i = sp->len - 1; i >= 0; i--) { 3529 struct xfrm_state *x = sp->xvec[i]; 3530 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3531 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3532 return 0; 3533 } 3534 } 3535 } 3536 3537 pol = NULL; 3538 sk = sk_to_full_sk(sk); 3539 if (sk && sk->sk_policy[dir]) { 3540 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3541 if (IS_ERR(pol)) { 3542 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3543 return 0; 3544 } 3545 } 3546 3547 if (!pol) 3548 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3549 3550 if (IS_ERR(pol)) { 3551 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3552 return 0; 3553 } 3554 3555 if (!pol) { 3556 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3557 xfrm_secpath_reject(xerr_idx, skb, &fl); 3558 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3559 return 0; 3560 } 3561 return 1; 3562 } 3563 3564 pol->curlft.use_time = ktime_get_real_seconds(); 3565 3566 pols[0] = pol; 3567 npols++; 3568 #ifdef CONFIG_XFRM_SUB_POLICY 3569 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3570 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3571 &fl, family, 3572 XFRM_POLICY_IN, if_id); 3573 if (pols[1]) { 3574 if (IS_ERR(pols[1])) { 3575 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3576 return 0; 3577 } 3578 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3579 npols++; 3580 } 3581 } 3582 #endif 3583 3584 if (pol->action == XFRM_POLICY_ALLOW) { 3585 static struct sec_path dummy; 3586 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3587 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3588 struct xfrm_tmpl **tpp = tp; 3589 int ti = 0; 3590 int i, k; 3591 3592 sp = skb_sec_path(skb); 3593 if (!sp) 3594 sp = &dummy; 3595 3596 for (pi = 0; pi < npols; pi++) { 3597 if (pols[pi] != pol && 3598 pols[pi]->action != XFRM_POLICY_ALLOW) { 3599 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3600 goto reject; 3601 } 3602 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3603 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3604 goto reject_error; 3605 } 3606 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3607 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3608 } 3609 xfrm_nr = ti; 3610 if (npols > 1) { 3611 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3612 tpp = stp; 3613 } 3614 3615 /* For each tunnel xfrm, find the first matching tmpl. 3616 * For each tmpl before that, find corresponding xfrm. 3617 * Order is _important_. Later we will implement 3618 * some barriers, but at the moment barriers 3619 * are implied between each two transformations. 3620 */ 3621 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3622 k = xfrm_policy_ok(tpp[i], sp, k, family); 3623 if (k < 0) { 3624 if (k < -1) 3625 /* "-2 - errored_index" returned */ 3626 xerr_idx = -(2+k); 3627 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3628 goto reject; 3629 } 3630 } 3631 3632 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3633 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3634 goto reject; 3635 } 3636 3637 xfrm_pols_put(pols, npols); 3638 return 1; 3639 } 3640 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3641 3642 reject: 3643 xfrm_secpath_reject(xerr_idx, skb, &fl); 3644 reject_error: 3645 xfrm_pols_put(pols, npols); 3646 return 0; 3647 } 3648 EXPORT_SYMBOL(__xfrm_policy_check); 3649 3650 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3651 { 3652 struct net *net = dev_net(skb->dev); 3653 struct flowi fl; 3654 struct dst_entry *dst; 3655 int res = 1; 3656 3657 if (xfrm_decode_session(skb, &fl, family) < 0) { 3658 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3659 return 0; 3660 } 3661 3662 skb_dst_force(skb); 3663 if (!skb_dst(skb)) { 3664 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3665 return 0; 3666 } 3667 3668 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3669 if (IS_ERR(dst)) { 3670 res = 0; 3671 dst = NULL; 3672 } 3673 skb_dst_set(skb, dst); 3674 return res; 3675 } 3676 EXPORT_SYMBOL(__xfrm_route_forward); 3677 3678 /* Optimize later using cookies and generation ids. */ 3679 3680 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3681 { 3682 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3683 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3684 * get validated by dst_ops->check on every use. We do this 3685 * because when a normal route referenced by an XFRM dst is 3686 * obsoleted we do not go looking around for all parent 3687 * referencing XFRM dsts so that we can invalidate them. It 3688 * is just too much work. Instead we make the checks here on 3689 * every use. For example: 3690 * 3691 * XFRM dst A --> IPv4 dst X 3692 * 3693 * X is the "xdst->route" of A (X is also the "dst->path" of A 3694 * in this example). If X is marked obsolete, "A" will not 3695 * notice. That's what we are validating here via the 3696 * stale_bundle() check. 3697 * 3698 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3699 * be marked on it. 3700 * This will force stale_bundle() to fail on any xdst bundle with 3701 * this dst linked in it. 3702 */ 3703 if (dst->obsolete < 0 && !stale_bundle(dst)) 3704 return dst; 3705 3706 return NULL; 3707 } 3708 3709 static int stale_bundle(struct dst_entry *dst) 3710 { 3711 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3712 } 3713 3714 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3715 { 3716 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3717 dst->dev = dev_net(dev)->loopback_dev; 3718 dev_hold(dst->dev); 3719 dev_put(dev); 3720 } 3721 } 3722 EXPORT_SYMBOL(xfrm_dst_ifdown); 3723 3724 static void xfrm_link_failure(struct sk_buff *skb) 3725 { 3726 /* Impossible. Such dst must be popped before reaches point of failure. */ 3727 } 3728 3729 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3730 { 3731 if (dst) { 3732 if (dst->obsolete) { 3733 dst_release(dst); 3734 dst = NULL; 3735 } 3736 } 3737 return dst; 3738 } 3739 3740 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3741 { 3742 while (nr--) { 3743 struct xfrm_dst *xdst = bundle[nr]; 3744 u32 pmtu, route_mtu_cached; 3745 struct dst_entry *dst; 3746 3747 dst = &xdst->u.dst; 3748 pmtu = dst_mtu(xfrm_dst_child(dst)); 3749 xdst->child_mtu_cached = pmtu; 3750 3751 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3752 3753 route_mtu_cached = dst_mtu(xdst->route); 3754 xdst->route_mtu_cached = route_mtu_cached; 3755 3756 if (pmtu > route_mtu_cached) 3757 pmtu = route_mtu_cached; 3758 3759 dst_metric_set(dst, RTAX_MTU, pmtu); 3760 } 3761 } 3762 3763 /* Check that the bundle accepts the flow and its components are 3764 * still valid. 3765 */ 3766 3767 static int xfrm_bundle_ok(struct xfrm_dst *first) 3768 { 3769 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3770 struct dst_entry *dst = &first->u.dst; 3771 struct xfrm_dst *xdst; 3772 int start_from, nr; 3773 u32 mtu; 3774 3775 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3776 (dst->dev && !netif_running(dst->dev))) 3777 return 0; 3778 3779 if (dst->flags & DST_XFRM_QUEUE) 3780 return 1; 3781 3782 start_from = nr = 0; 3783 do { 3784 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3785 3786 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3787 return 0; 3788 if (xdst->xfrm_genid != dst->xfrm->genid) 3789 return 0; 3790 if (xdst->num_pols > 0 && 3791 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3792 return 0; 3793 3794 bundle[nr++] = xdst; 3795 3796 mtu = dst_mtu(xfrm_dst_child(dst)); 3797 if (xdst->child_mtu_cached != mtu) { 3798 start_from = nr; 3799 xdst->child_mtu_cached = mtu; 3800 } 3801 3802 if (!dst_check(xdst->route, xdst->route_cookie)) 3803 return 0; 3804 mtu = dst_mtu(xdst->route); 3805 if (xdst->route_mtu_cached != mtu) { 3806 start_from = nr; 3807 xdst->route_mtu_cached = mtu; 3808 } 3809 3810 dst = xfrm_dst_child(dst); 3811 } while (dst->xfrm); 3812 3813 if (likely(!start_from)) 3814 return 1; 3815 3816 xdst = bundle[start_from - 1]; 3817 mtu = xdst->child_mtu_cached; 3818 while (start_from--) { 3819 dst = &xdst->u.dst; 3820 3821 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3822 if (mtu > xdst->route_mtu_cached) 3823 mtu = xdst->route_mtu_cached; 3824 dst_metric_set(dst, RTAX_MTU, mtu); 3825 if (!start_from) 3826 break; 3827 3828 xdst = bundle[start_from - 1]; 3829 xdst->child_mtu_cached = mtu; 3830 } 3831 3832 return 1; 3833 } 3834 3835 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3836 { 3837 return dst_metric_advmss(xfrm_dst_path(dst)); 3838 } 3839 3840 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3841 { 3842 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3843 3844 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3845 } 3846 3847 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3848 const void *daddr) 3849 { 3850 while (dst->xfrm) { 3851 const struct xfrm_state *xfrm = dst->xfrm; 3852 3853 dst = xfrm_dst_child(dst); 3854 3855 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3856 continue; 3857 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3858 daddr = xfrm->coaddr; 3859 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3860 daddr = &xfrm->id.daddr; 3861 } 3862 return daddr; 3863 } 3864 3865 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3866 struct sk_buff *skb, 3867 const void *daddr) 3868 { 3869 const struct dst_entry *path = xfrm_dst_path(dst); 3870 3871 if (!skb) 3872 daddr = xfrm_get_dst_nexthop(dst, daddr); 3873 return path->ops->neigh_lookup(path, skb, daddr); 3874 } 3875 3876 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3877 { 3878 const struct dst_entry *path = xfrm_dst_path(dst); 3879 3880 daddr = xfrm_get_dst_nexthop(dst, daddr); 3881 path->ops->confirm_neigh(path, daddr); 3882 } 3883 3884 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3885 { 3886 int err = 0; 3887 3888 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3889 return -EAFNOSUPPORT; 3890 3891 spin_lock(&xfrm_policy_afinfo_lock); 3892 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3893 err = -EEXIST; 3894 else { 3895 struct dst_ops *dst_ops = afinfo->dst_ops; 3896 if (likely(dst_ops->kmem_cachep == NULL)) 3897 dst_ops->kmem_cachep = xfrm_dst_cache; 3898 if (likely(dst_ops->check == NULL)) 3899 dst_ops->check = xfrm_dst_check; 3900 if (likely(dst_ops->default_advmss == NULL)) 3901 dst_ops->default_advmss = xfrm_default_advmss; 3902 if (likely(dst_ops->mtu == NULL)) 3903 dst_ops->mtu = xfrm_mtu; 3904 if (likely(dst_ops->negative_advice == NULL)) 3905 dst_ops->negative_advice = xfrm_negative_advice; 3906 if (likely(dst_ops->link_failure == NULL)) 3907 dst_ops->link_failure = xfrm_link_failure; 3908 if (likely(dst_ops->neigh_lookup == NULL)) 3909 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3910 if (likely(!dst_ops->confirm_neigh)) 3911 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3912 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3913 } 3914 spin_unlock(&xfrm_policy_afinfo_lock); 3915 3916 return err; 3917 } 3918 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3919 3920 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3921 { 3922 struct dst_ops *dst_ops = afinfo->dst_ops; 3923 int i; 3924 3925 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3926 if (xfrm_policy_afinfo[i] != afinfo) 3927 continue; 3928 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3929 break; 3930 } 3931 3932 synchronize_rcu(); 3933 3934 dst_ops->kmem_cachep = NULL; 3935 dst_ops->check = NULL; 3936 dst_ops->negative_advice = NULL; 3937 dst_ops->link_failure = NULL; 3938 } 3939 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3940 3941 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3942 { 3943 spin_lock(&xfrm_if_cb_lock); 3944 rcu_assign_pointer(xfrm_if_cb, ifcb); 3945 spin_unlock(&xfrm_if_cb_lock); 3946 } 3947 EXPORT_SYMBOL(xfrm_if_register_cb); 3948 3949 void xfrm_if_unregister_cb(void) 3950 { 3951 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3952 synchronize_rcu(); 3953 } 3954 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3955 3956 #ifdef CONFIG_XFRM_STATISTICS 3957 static int __net_init xfrm_statistics_init(struct net *net) 3958 { 3959 int rv; 3960 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3961 if (!net->mib.xfrm_statistics) 3962 return -ENOMEM; 3963 rv = xfrm_proc_init(net); 3964 if (rv < 0) 3965 free_percpu(net->mib.xfrm_statistics); 3966 return rv; 3967 } 3968 3969 static void xfrm_statistics_fini(struct net *net) 3970 { 3971 xfrm_proc_fini(net); 3972 free_percpu(net->mib.xfrm_statistics); 3973 } 3974 #else 3975 static int __net_init xfrm_statistics_init(struct net *net) 3976 { 3977 return 0; 3978 } 3979 3980 static void xfrm_statistics_fini(struct net *net) 3981 { 3982 } 3983 #endif 3984 3985 static int __net_init xfrm_policy_init(struct net *net) 3986 { 3987 unsigned int hmask, sz; 3988 int dir, err; 3989 3990 if (net_eq(net, &init_net)) { 3991 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 3992 sizeof(struct xfrm_dst), 3993 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 3994 NULL); 3995 err = rhashtable_init(&xfrm_policy_inexact_table, 3996 &xfrm_pol_inexact_params); 3997 BUG_ON(err); 3998 } 3999 4000 hmask = 8 - 1; 4001 sz = (hmask+1) * sizeof(struct hlist_head); 4002 4003 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4004 if (!net->xfrm.policy_byidx) 4005 goto out_byidx; 4006 net->xfrm.policy_idx_hmask = hmask; 4007 4008 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4009 struct xfrm_policy_hash *htab; 4010 4011 net->xfrm.policy_count[dir] = 0; 4012 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4013 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4014 4015 htab = &net->xfrm.policy_bydst[dir]; 4016 htab->table = xfrm_hash_alloc(sz); 4017 if (!htab->table) 4018 goto out_bydst; 4019 htab->hmask = hmask; 4020 htab->dbits4 = 32; 4021 htab->sbits4 = 32; 4022 htab->dbits6 = 128; 4023 htab->sbits6 = 128; 4024 } 4025 net->xfrm.policy_hthresh.lbits4 = 32; 4026 net->xfrm.policy_hthresh.rbits4 = 32; 4027 net->xfrm.policy_hthresh.lbits6 = 128; 4028 net->xfrm.policy_hthresh.rbits6 = 128; 4029 4030 seqlock_init(&net->xfrm.policy_hthresh.lock); 4031 4032 INIT_LIST_HEAD(&net->xfrm.policy_all); 4033 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4034 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4035 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4036 return 0; 4037 4038 out_bydst: 4039 for (dir--; dir >= 0; dir--) { 4040 struct xfrm_policy_hash *htab; 4041 4042 htab = &net->xfrm.policy_bydst[dir]; 4043 xfrm_hash_free(htab->table, sz); 4044 } 4045 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4046 out_byidx: 4047 return -ENOMEM; 4048 } 4049 4050 static void xfrm_policy_fini(struct net *net) 4051 { 4052 struct xfrm_pol_inexact_bin *b, *t; 4053 unsigned int sz; 4054 int dir; 4055 4056 flush_work(&net->xfrm.policy_hash_work); 4057 #ifdef CONFIG_XFRM_SUB_POLICY 4058 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4059 #endif 4060 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4061 4062 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4063 4064 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4065 struct xfrm_policy_hash *htab; 4066 4067 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4068 4069 htab = &net->xfrm.policy_bydst[dir]; 4070 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4071 WARN_ON(!hlist_empty(htab->table)); 4072 xfrm_hash_free(htab->table, sz); 4073 } 4074 4075 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4076 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4077 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4078 4079 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4080 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4081 __xfrm_policy_inexact_prune_bin(b, true); 4082 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4083 } 4084 4085 static int __net_init xfrm_net_init(struct net *net) 4086 { 4087 int rv; 4088 4089 /* Initialize the per-net locks here */ 4090 spin_lock_init(&net->xfrm.xfrm_state_lock); 4091 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4092 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4093 4094 rv = xfrm_statistics_init(net); 4095 if (rv < 0) 4096 goto out_statistics; 4097 rv = xfrm_state_init(net); 4098 if (rv < 0) 4099 goto out_state; 4100 rv = xfrm_policy_init(net); 4101 if (rv < 0) 4102 goto out_policy; 4103 rv = xfrm_sysctl_init(net); 4104 if (rv < 0) 4105 goto out_sysctl; 4106 4107 return 0; 4108 4109 out_sysctl: 4110 xfrm_policy_fini(net); 4111 out_policy: 4112 xfrm_state_fini(net); 4113 out_state: 4114 xfrm_statistics_fini(net); 4115 out_statistics: 4116 return rv; 4117 } 4118 4119 static void __net_exit xfrm_net_exit(struct net *net) 4120 { 4121 xfrm_sysctl_fini(net); 4122 xfrm_policy_fini(net); 4123 xfrm_state_fini(net); 4124 xfrm_statistics_fini(net); 4125 } 4126 4127 static struct pernet_operations __net_initdata xfrm_net_ops = { 4128 .init = xfrm_net_init, 4129 .exit = xfrm_net_exit, 4130 }; 4131 4132 void __init xfrm_init(void) 4133 { 4134 register_pernet_subsys(&xfrm_net_ops); 4135 xfrm_dev_init(); 4136 seqcount_mutex_init(&xfrm_policy_hash_generation, &hash_resize_mutex); 4137 xfrm_input_init(); 4138 4139 #ifdef CONFIG_XFRM_ESPINTCP 4140 espintcp_init(); 4141 #endif 4142 } 4143 4144 #ifdef CONFIG_AUDITSYSCALL 4145 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4146 struct audit_buffer *audit_buf) 4147 { 4148 struct xfrm_sec_ctx *ctx = xp->security; 4149 struct xfrm_selector *sel = &xp->selector; 4150 4151 if (ctx) 4152 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4153 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4154 4155 switch (sel->family) { 4156 case AF_INET: 4157 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4158 if (sel->prefixlen_s != 32) 4159 audit_log_format(audit_buf, " src_prefixlen=%d", 4160 sel->prefixlen_s); 4161 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4162 if (sel->prefixlen_d != 32) 4163 audit_log_format(audit_buf, " dst_prefixlen=%d", 4164 sel->prefixlen_d); 4165 break; 4166 case AF_INET6: 4167 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4168 if (sel->prefixlen_s != 128) 4169 audit_log_format(audit_buf, " src_prefixlen=%d", 4170 sel->prefixlen_s); 4171 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4172 if (sel->prefixlen_d != 128) 4173 audit_log_format(audit_buf, " dst_prefixlen=%d", 4174 sel->prefixlen_d); 4175 break; 4176 } 4177 } 4178 4179 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4180 { 4181 struct audit_buffer *audit_buf; 4182 4183 audit_buf = xfrm_audit_start("SPD-add"); 4184 if (audit_buf == NULL) 4185 return; 4186 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4187 audit_log_format(audit_buf, " res=%u", result); 4188 xfrm_audit_common_policyinfo(xp, audit_buf); 4189 audit_log_end(audit_buf); 4190 } 4191 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4192 4193 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4194 bool task_valid) 4195 { 4196 struct audit_buffer *audit_buf; 4197 4198 audit_buf = xfrm_audit_start("SPD-delete"); 4199 if (audit_buf == NULL) 4200 return; 4201 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4202 audit_log_format(audit_buf, " res=%u", result); 4203 xfrm_audit_common_policyinfo(xp, audit_buf); 4204 audit_log_end(audit_buf); 4205 } 4206 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4207 #endif 4208 4209 #ifdef CONFIG_XFRM_MIGRATE 4210 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4211 const struct xfrm_selector *sel_tgt) 4212 { 4213 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4214 if (sel_tgt->family == sel_cmp->family && 4215 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4216 sel_cmp->family) && 4217 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4218 sel_cmp->family) && 4219 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4220 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4221 return true; 4222 } 4223 } else { 4224 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4225 return true; 4226 } 4227 } 4228 return false; 4229 } 4230 4231 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4232 u8 dir, u8 type, struct net *net) 4233 { 4234 struct xfrm_policy *pol, *ret = NULL; 4235 struct hlist_head *chain; 4236 u32 priority = ~0U; 4237 4238 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4239 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4240 hlist_for_each_entry(pol, chain, bydst) { 4241 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4242 pol->type == type) { 4243 ret = pol; 4244 priority = ret->priority; 4245 break; 4246 } 4247 } 4248 chain = &net->xfrm.policy_inexact[dir]; 4249 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4250 if ((pol->priority >= priority) && ret) 4251 break; 4252 4253 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4254 pol->type == type) { 4255 ret = pol; 4256 break; 4257 } 4258 } 4259 4260 xfrm_pol_hold(ret); 4261 4262 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4263 4264 return ret; 4265 } 4266 4267 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4268 { 4269 int match = 0; 4270 4271 if (t->mode == m->mode && t->id.proto == m->proto && 4272 (m->reqid == 0 || t->reqid == m->reqid)) { 4273 switch (t->mode) { 4274 case XFRM_MODE_TUNNEL: 4275 case XFRM_MODE_BEET: 4276 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4277 m->old_family) && 4278 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4279 m->old_family)) { 4280 match = 1; 4281 } 4282 break; 4283 case XFRM_MODE_TRANSPORT: 4284 /* in case of transport mode, template does not store 4285 any IP addresses, hence we just compare mode and 4286 protocol */ 4287 match = 1; 4288 break; 4289 default: 4290 break; 4291 } 4292 } 4293 return match; 4294 } 4295 4296 /* update endpoint address(es) of template(s) */ 4297 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4298 struct xfrm_migrate *m, int num_migrate) 4299 { 4300 struct xfrm_migrate *mp; 4301 int i, j, n = 0; 4302 4303 write_lock_bh(&pol->lock); 4304 if (unlikely(pol->walk.dead)) { 4305 /* target policy has been deleted */ 4306 write_unlock_bh(&pol->lock); 4307 return -ENOENT; 4308 } 4309 4310 for (i = 0; i < pol->xfrm_nr; i++) { 4311 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4312 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4313 continue; 4314 n++; 4315 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4316 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4317 continue; 4318 /* update endpoints */ 4319 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4320 sizeof(pol->xfrm_vec[i].id.daddr)); 4321 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4322 sizeof(pol->xfrm_vec[i].saddr)); 4323 pol->xfrm_vec[i].encap_family = mp->new_family; 4324 /* flush bundles */ 4325 atomic_inc(&pol->genid); 4326 } 4327 } 4328 4329 write_unlock_bh(&pol->lock); 4330 4331 if (!n) 4332 return -ENODATA; 4333 4334 return 0; 4335 } 4336 4337 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4338 { 4339 int i, j; 4340 4341 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4342 return -EINVAL; 4343 4344 for (i = 0; i < num_migrate; i++) { 4345 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4346 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4347 return -EINVAL; 4348 4349 /* check if there is any duplicated entry */ 4350 for (j = i + 1; j < num_migrate; j++) { 4351 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4352 sizeof(m[i].old_daddr)) && 4353 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4354 sizeof(m[i].old_saddr)) && 4355 m[i].proto == m[j].proto && 4356 m[i].mode == m[j].mode && 4357 m[i].reqid == m[j].reqid && 4358 m[i].old_family == m[j].old_family) 4359 return -EINVAL; 4360 } 4361 } 4362 4363 return 0; 4364 } 4365 4366 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4367 struct xfrm_migrate *m, int num_migrate, 4368 struct xfrm_kmaddress *k, struct net *net, 4369 struct xfrm_encap_tmpl *encap) 4370 { 4371 int i, err, nx_cur = 0, nx_new = 0; 4372 struct xfrm_policy *pol = NULL; 4373 struct xfrm_state *x, *xc; 4374 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4375 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4376 struct xfrm_migrate *mp; 4377 4378 /* Stage 0 - sanity checks */ 4379 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4380 goto out; 4381 4382 if (dir >= XFRM_POLICY_MAX) { 4383 err = -EINVAL; 4384 goto out; 4385 } 4386 4387 /* Stage 1 - find policy */ 4388 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4389 err = -ENOENT; 4390 goto out; 4391 } 4392 4393 /* Stage 2 - find and update state(s) */ 4394 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4395 if ((x = xfrm_migrate_state_find(mp, net))) { 4396 x_cur[nx_cur] = x; 4397 nx_cur++; 4398 xc = xfrm_state_migrate(x, mp, encap); 4399 if (xc) { 4400 x_new[nx_new] = xc; 4401 nx_new++; 4402 } else { 4403 err = -ENODATA; 4404 goto restore_state; 4405 } 4406 } 4407 } 4408 4409 /* Stage 3 - update policy */ 4410 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4411 goto restore_state; 4412 4413 /* Stage 4 - delete old state(s) */ 4414 if (nx_cur) { 4415 xfrm_states_put(x_cur, nx_cur); 4416 xfrm_states_delete(x_cur, nx_cur); 4417 } 4418 4419 /* Stage 5 - announce */ 4420 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4421 4422 xfrm_pol_put(pol); 4423 4424 return 0; 4425 out: 4426 return err; 4427 4428 restore_state: 4429 if (pol) 4430 xfrm_pol_put(pol); 4431 if (nx_cur) 4432 xfrm_states_put(x_cur, nx_cur); 4433 if (nx_new) 4434 xfrm_states_delete(x_new, nx_new); 4435 4436 return err; 4437 } 4438 EXPORT_SYMBOL(xfrm_migrate); 4439 #endif 4440