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_INET_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_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_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 sucessful 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_init(&bin->count); 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 unsigned int pdw, pbi; 797 int delta = 0; 798 799 switch (family) { 800 case AF_INET: 801 if (sizeof(long) == 4 && prefixlen == 0) 802 return ntohl(a->a4) - ntohl(b->a4); 803 return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) - 804 (ntohl(b->a4) & ((~0UL << (32 - prefixlen)))); 805 case AF_INET6: 806 pdw = prefixlen >> 5; 807 pbi = prefixlen & 0x1f; 808 809 if (pdw) { 810 delta = memcmp(a->a6, b->a6, pdw << 2); 811 if (delta) 812 return delta; 813 } 814 if (pbi) { 815 u32 mask = ~0u << (32 - pbi); 816 817 delta = (ntohl(a->a6[pdw]) & mask) - 818 (ntohl(b->a6[pdw]) & mask); 819 } 820 break; 821 default: 822 break; 823 } 824 825 return delta; 826 } 827 828 static void xfrm_policy_inexact_list_reinsert(struct net *net, 829 struct xfrm_pol_inexact_node *n, 830 u16 family) 831 { 832 unsigned int matched_s, matched_d; 833 struct xfrm_policy *policy, *p; 834 835 matched_s = 0; 836 matched_d = 0; 837 838 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 839 struct hlist_node *newpos = NULL; 840 bool matches_s, matches_d; 841 842 if (!policy->bydst_reinsert) 843 continue; 844 845 WARN_ON_ONCE(policy->family != family); 846 847 policy->bydst_reinsert = false; 848 hlist_for_each_entry(p, &n->hhead, bydst) { 849 if (policy->priority > p->priority) 850 newpos = &p->bydst; 851 else if (policy->priority == p->priority && 852 policy->pos > p->pos) 853 newpos = &p->bydst; 854 else 855 break; 856 } 857 858 if (newpos) 859 hlist_add_behind_rcu(&policy->bydst, newpos); 860 else 861 hlist_add_head_rcu(&policy->bydst, &n->hhead); 862 863 /* paranoia checks follow. 864 * Check that the reinserted policy matches at least 865 * saddr or daddr for current node prefix. 866 * 867 * Matching both is fine, matching saddr in one policy 868 * (but not daddr) and then matching only daddr in another 869 * is a bug. 870 */ 871 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 872 &n->addr, 873 n->prefixlen, 874 family) == 0; 875 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 876 &n->addr, 877 n->prefixlen, 878 family) == 0; 879 if (matches_s && matches_d) 880 continue; 881 882 WARN_ON_ONCE(!matches_s && !matches_d); 883 if (matches_s) 884 matched_s++; 885 if (matches_d) 886 matched_d++; 887 WARN_ON_ONCE(matched_s && matched_d); 888 } 889 } 890 891 static void xfrm_policy_inexact_node_reinsert(struct net *net, 892 struct xfrm_pol_inexact_node *n, 893 struct rb_root *new, 894 u16 family) 895 { 896 struct xfrm_pol_inexact_node *node; 897 struct rb_node **p, *parent; 898 899 /* we should not have another subtree here */ 900 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 901 restart: 902 parent = NULL; 903 p = &new->rb_node; 904 while (*p) { 905 u8 prefixlen; 906 int delta; 907 908 parent = *p; 909 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 910 911 prefixlen = min(node->prefixlen, n->prefixlen); 912 913 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 914 prefixlen, family); 915 if (delta < 0) { 916 p = &parent->rb_left; 917 } else if (delta > 0) { 918 p = &parent->rb_right; 919 } else { 920 bool same_prefixlen = node->prefixlen == n->prefixlen; 921 struct xfrm_policy *tmp; 922 923 hlist_for_each_entry(tmp, &n->hhead, bydst) { 924 tmp->bydst_reinsert = true; 925 hlist_del_rcu(&tmp->bydst); 926 } 927 928 node->prefixlen = prefixlen; 929 930 xfrm_policy_inexact_list_reinsert(net, node, family); 931 932 if (same_prefixlen) { 933 kfree_rcu(n, rcu); 934 return; 935 } 936 937 rb_erase(*p, new); 938 kfree_rcu(n, rcu); 939 n = node; 940 goto restart; 941 } 942 } 943 944 rb_link_node_rcu(&n->node, parent, p); 945 rb_insert_color(&n->node, new); 946 } 947 948 /* merge nodes v and n */ 949 static void xfrm_policy_inexact_node_merge(struct net *net, 950 struct xfrm_pol_inexact_node *v, 951 struct xfrm_pol_inexact_node *n, 952 u16 family) 953 { 954 struct xfrm_pol_inexact_node *node; 955 struct xfrm_policy *tmp; 956 struct rb_node *rnode; 957 958 /* To-be-merged node v has a subtree. 959 * 960 * Dismantle it and insert its nodes to n->root. 961 */ 962 while ((rnode = rb_first(&v->root)) != NULL) { 963 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 964 rb_erase(&node->node, &v->root); 965 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 966 family); 967 } 968 969 hlist_for_each_entry(tmp, &v->hhead, bydst) { 970 tmp->bydst_reinsert = true; 971 hlist_del_rcu(&tmp->bydst); 972 } 973 974 xfrm_policy_inexact_list_reinsert(net, n, family); 975 } 976 977 static struct xfrm_pol_inexact_node * 978 xfrm_policy_inexact_insert_node(struct net *net, 979 struct rb_root *root, 980 xfrm_address_t *addr, 981 u16 family, u8 prefixlen, u8 dir) 982 { 983 struct xfrm_pol_inexact_node *cached = NULL; 984 struct rb_node **p, *parent = NULL; 985 struct xfrm_pol_inexact_node *node; 986 987 p = &root->rb_node; 988 while (*p) { 989 int delta; 990 991 parent = *p; 992 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 993 994 delta = xfrm_policy_addr_delta(addr, &node->addr, 995 node->prefixlen, 996 family); 997 if (delta == 0 && prefixlen >= node->prefixlen) { 998 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 999 return node; 1000 } 1001 1002 if (delta < 0) 1003 p = &parent->rb_left; 1004 else 1005 p = &parent->rb_right; 1006 1007 if (prefixlen < node->prefixlen) { 1008 delta = xfrm_policy_addr_delta(addr, &node->addr, 1009 prefixlen, 1010 family); 1011 if (delta) 1012 continue; 1013 1014 /* This node is a subnet of the new prefix. It needs 1015 * to be removed and re-inserted with the smaller 1016 * prefix and all nodes that are now also covered 1017 * by the reduced prefixlen. 1018 */ 1019 rb_erase(&node->node, root); 1020 1021 if (!cached) { 1022 xfrm_pol_inexact_node_init(node, addr, 1023 prefixlen); 1024 cached = node; 1025 } else { 1026 /* This node also falls within the new 1027 * prefixlen. Merge the to-be-reinserted 1028 * node and this one. 1029 */ 1030 xfrm_policy_inexact_node_merge(net, node, 1031 cached, family); 1032 kfree_rcu(node, rcu); 1033 } 1034 1035 /* restart */ 1036 p = &root->rb_node; 1037 parent = NULL; 1038 } 1039 } 1040 1041 node = cached; 1042 if (!node) { 1043 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1044 if (!node) 1045 return NULL; 1046 } 1047 1048 rb_link_node_rcu(&node->node, parent, p); 1049 rb_insert_color(&node->node, root); 1050 1051 return node; 1052 } 1053 1054 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1055 { 1056 struct xfrm_pol_inexact_node *node; 1057 struct rb_node *rn = rb_first(r); 1058 1059 while (rn) { 1060 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1061 1062 xfrm_policy_inexact_gc_tree(&node->root, rm); 1063 rn = rb_next(rn); 1064 1065 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1066 WARN_ON_ONCE(rm); 1067 continue; 1068 } 1069 1070 rb_erase(&node->node, r); 1071 kfree_rcu(node, rcu); 1072 } 1073 } 1074 1075 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1076 { 1077 write_seqcount_begin(&b->count); 1078 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1079 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1080 write_seqcount_end(&b->count); 1081 1082 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1083 !hlist_empty(&b->hhead)) { 1084 WARN_ON_ONCE(net_exit); 1085 return; 1086 } 1087 1088 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1089 xfrm_pol_inexact_params) == 0) { 1090 list_del(&b->inexact_bins); 1091 kfree_rcu(b, rcu); 1092 } 1093 } 1094 1095 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1096 { 1097 struct net *net = read_pnet(&b->k.net); 1098 1099 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1100 __xfrm_policy_inexact_prune_bin(b, false); 1101 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1102 } 1103 1104 static void __xfrm_policy_inexact_flush(struct net *net) 1105 { 1106 struct xfrm_pol_inexact_bin *bin, *t; 1107 1108 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1109 1110 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1111 __xfrm_policy_inexact_prune_bin(bin, false); 1112 } 1113 1114 static struct hlist_head * 1115 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1116 struct xfrm_policy *policy, u8 dir) 1117 { 1118 struct xfrm_pol_inexact_node *n; 1119 struct net *net; 1120 1121 net = xp_net(policy); 1122 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1123 1124 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1125 return &bin->hhead; 1126 1127 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1128 policy->family, 1129 policy->selector.prefixlen_d)) { 1130 write_seqcount_begin(&bin->count); 1131 n = xfrm_policy_inexact_insert_node(net, 1132 &bin->root_s, 1133 &policy->selector.saddr, 1134 policy->family, 1135 policy->selector.prefixlen_s, 1136 dir); 1137 write_seqcount_end(&bin->count); 1138 if (!n) 1139 return NULL; 1140 1141 return &n->hhead; 1142 } 1143 1144 /* daddr is fixed */ 1145 write_seqcount_begin(&bin->count); 1146 n = xfrm_policy_inexact_insert_node(net, 1147 &bin->root_d, 1148 &policy->selector.daddr, 1149 policy->family, 1150 policy->selector.prefixlen_d, dir); 1151 write_seqcount_end(&bin->count); 1152 if (!n) 1153 return NULL; 1154 1155 /* saddr is wildcard */ 1156 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1157 policy->family, 1158 policy->selector.prefixlen_s)) 1159 return &n->hhead; 1160 1161 write_seqcount_begin(&bin->count); 1162 n = xfrm_policy_inexact_insert_node(net, 1163 &n->root, 1164 &policy->selector.saddr, 1165 policy->family, 1166 policy->selector.prefixlen_s, dir); 1167 write_seqcount_end(&bin->count); 1168 if (!n) 1169 return NULL; 1170 1171 return &n->hhead; 1172 } 1173 1174 static struct xfrm_policy * 1175 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1176 { 1177 struct xfrm_pol_inexact_bin *bin; 1178 struct xfrm_policy *delpol; 1179 struct hlist_head *chain; 1180 struct net *net; 1181 1182 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1183 if (!bin) 1184 return ERR_PTR(-ENOMEM); 1185 1186 net = xp_net(policy); 1187 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1188 1189 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1190 if (!chain) { 1191 __xfrm_policy_inexact_prune_bin(bin, false); 1192 return ERR_PTR(-ENOMEM); 1193 } 1194 1195 delpol = xfrm_policy_insert_list(chain, policy, excl); 1196 if (delpol && excl) { 1197 __xfrm_policy_inexact_prune_bin(bin, false); 1198 return ERR_PTR(-EEXIST); 1199 } 1200 1201 chain = &net->xfrm.policy_inexact[dir]; 1202 xfrm_policy_insert_inexact_list(chain, policy); 1203 1204 if (delpol) 1205 __xfrm_policy_inexact_prune_bin(bin, false); 1206 1207 return delpol; 1208 } 1209 1210 static void xfrm_hash_rebuild(struct work_struct *work) 1211 { 1212 struct net *net = container_of(work, struct net, 1213 xfrm.policy_hthresh.work); 1214 unsigned int hmask; 1215 struct xfrm_policy *pol; 1216 struct xfrm_policy *policy; 1217 struct hlist_head *chain; 1218 struct hlist_head *odst; 1219 struct hlist_node *newpos; 1220 int i; 1221 int dir; 1222 unsigned seq; 1223 u8 lbits4, rbits4, lbits6, rbits6; 1224 1225 mutex_lock(&hash_resize_mutex); 1226 1227 /* read selector prefixlen thresholds */ 1228 do { 1229 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1230 1231 lbits4 = net->xfrm.policy_hthresh.lbits4; 1232 rbits4 = net->xfrm.policy_hthresh.rbits4; 1233 lbits6 = net->xfrm.policy_hthresh.lbits6; 1234 rbits6 = net->xfrm.policy_hthresh.rbits6; 1235 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1236 1237 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1238 write_seqcount_begin(&xfrm_policy_hash_generation); 1239 1240 /* make sure that we can insert the indirect policies again before 1241 * we start with destructive action. 1242 */ 1243 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1244 struct xfrm_pol_inexact_bin *bin; 1245 u8 dbits, sbits; 1246 1247 dir = xfrm_policy_id2dir(policy->index); 1248 if (policy->walk.dead || dir >= XFRM_POLICY_MAX) 1249 continue; 1250 1251 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1252 if (policy->family == AF_INET) { 1253 dbits = rbits4; 1254 sbits = lbits4; 1255 } else { 1256 dbits = rbits6; 1257 sbits = lbits6; 1258 } 1259 } else { 1260 if (policy->family == AF_INET) { 1261 dbits = lbits4; 1262 sbits = rbits4; 1263 } else { 1264 dbits = lbits6; 1265 sbits = rbits6; 1266 } 1267 } 1268 1269 if (policy->selector.prefixlen_d < dbits || 1270 policy->selector.prefixlen_s < sbits) 1271 continue; 1272 1273 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1274 if (!bin) 1275 goto out_unlock; 1276 1277 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1278 goto out_unlock; 1279 } 1280 1281 /* reset the bydst and inexact table in all directions */ 1282 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1283 struct hlist_node *n; 1284 1285 hlist_for_each_entry_safe(policy, n, 1286 &net->xfrm.policy_inexact[dir], 1287 bydst_inexact_list) { 1288 hlist_del_rcu(&policy->bydst); 1289 hlist_del_init(&policy->bydst_inexact_list); 1290 } 1291 1292 hmask = net->xfrm.policy_bydst[dir].hmask; 1293 odst = net->xfrm.policy_bydst[dir].table; 1294 for (i = hmask; i >= 0; i--) { 1295 hlist_for_each_entry_safe(policy, n, odst + i, bydst) 1296 hlist_del_rcu(&policy->bydst); 1297 } 1298 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1299 /* dir out => dst = remote, src = local */ 1300 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1301 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1302 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1303 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1304 } else { 1305 /* dir in/fwd => dst = local, src = remote */ 1306 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1307 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1308 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1309 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1310 } 1311 } 1312 1313 /* re-insert all policies by order of creation */ 1314 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1315 if (policy->walk.dead) 1316 continue; 1317 dir = xfrm_policy_id2dir(policy->index); 1318 if (dir >= XFRM_POLICY_MAX) { 1319 /* skip socket policies */ 1320 continue; 1321 } 1322 newpos = NULL; 1323 chain = policy_hash_bysel(net, &policy->selector, 1324 policy->family, dir); 1325 1326 if (!chain) { 1327 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1328 1329 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1330 continue; 1331 } 1332 1333 hlist_for_each_entry(pol, chain, bydst) { 1334 if (policy->priority >= pol->priority) 1335 newpos = &pol->bydst; 1336 else 1337 break; 1338 } 1339 if (newpos) 1340 hlist_add_behind_rcu(&policy->bydst, newpos); 1341 else 1342 hlist_add_head_rcu(&policy->bydst, chain); 1343 } 1344 1345 out_unlock: 1346 __xfrm_policy_inexact_flush(net); 1347 write_seqcount_end(&xfrm_policy_hash_generation); 1348 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1349 1350 mutex_unlock(&hash_resize_mutex); 1351 } 1352 1353 void xfrm_policy_hash_rebuild(struct net *net) 1354 { 1355 schedule_work(&net->xfrm.policy_hthresh.work); 1356 } 1357 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1358 1359 /* Generate new index... KAME seems to generate them ordered by cost 1360 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1361 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1362 { 1363 static u32 idx_generator; 1364 1365 for (;;) { 1366 struct hlist_head *list; 1367 struct xfrm_policy *p; 1368 u32 idx; 1369 int found; 1370 1371 if (!index) { 1372 idx = (idx_generator | dir); 1373 idx_generator += 8; 1374 } else { 1375 idx = index; 1376 index = 0; 1377 } 1378 1379 if (idx == 0) 1380 idx = 8; 1381 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1382 found = 0; 1383 hlist_for_each_entry(p, list, byidx) { 1384 if (p->index == idx) { 1385 found = 1; 1386 break; 1387 } 1388 } 1389 if (!found) 1390 return idx; 1391 } 1392 } 1393 1394 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1395 { 1396 u32 *p1 = (u32 *) s1; 1397 u32 *p2 = (u32 *) s2; 1398 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1399 int i; 1400 1401 for (i = 0; i < len; i++) { 1402 if (p1[i] != p2[i]) 1403 return 1; 1404 } 1405 1406 return 0; 1407 } 1408 1409 static void xfrm_policy_requeue(struct xfrm_policy *old, 1410 struct xfrm_policy *new) 1411 { 1412 struct xfrm_policy_queue *pq = &old->polq; 1413 struct sk_buff_head list; 1414 1415 if (skb_queue_empty(&pq->hold_queue)) 1416 return; 1417 1418 __skb_queue_head_init(&list); 1419 1420 spin_lock_bh(&pq->hold_queue.lock); 1421 skb_queue_splice_init(&pq->hold_queue, &list); 1422 if (del_timer(&pq->hold_timer)) 1423 xfrm_pol_put(old); 1424 spin_unlock_bh(&pq->hold_queue.lock); 1425 1426 pq = &new->polq; 1427 1428 spin_lock_bh(&pq->hold_queue.lock); 1429 skb_queue_splice(&list, &pq->hold_queue); 1430 pq->timeout = XFRM_QUEUE_TMO_MIN; 1431 if (!mod_timer(&pq->hold_timer, jiffies)) 1432 xfrm_pol_hold(new); 1433 spin_unlock_bh(&pq->hold_queue.lock); 1434 } 1435 1436 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 1437 struct xfrm_policy *pol) 1438 { 1439 u32 mark = policy->mark.v & policy->mark.m; 1440 1441 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 1442 return true; 1443 1444 if ((mark & pol->mark.m) == pol->mark.v && 1445 policy->priority == pol->priority) 1446 return true; 1447 1448 return false; 1449 } 1450 1451 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1452 { 1453 const struct xfrm_pol_inexact_key *k = data; 1454 u32 a = k->type << 24 | k->dir << 16 | k->family; 1455 1456 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1457 seed); 1458 } 1459 1460 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1461 { 1462 const struct xfrm_pol_inexact_bin *b = data; 1463 1464 return xfrm_pol_bin_key(&b->k, 0, seed); 1465 } 1466 1467 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1468 const void *ptr) 1469 { 1470 const struct xfrm_pol_inexact_key *key = arg->key; 1471 const struct xfrm_pol_inexact_bin *b = ptr; 1472 int ret; 1473 1474 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1475 return -1; 1476 1477 ret = b->k.dir ^ key->dir; 1478 if (ret) 1479 return ret; 1480 1481 ret = b->k.type ^ key->type; 1482 if (ret) 1483 return ret; 1484 1485 ret = b->k.family ^ key->family; 1486 if (ret) 1487 return ret; 1488 1489 return b->k.if_id ^ key->if_id; 1490 } 1491 1492 static const struct rhashtable_params xfrm_pol_inexact_params = { 1493 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1494 .hashfn = xfrm_pol_bin_key, 1495 .obj_hashfn = xfrm_pol_bin_obj, 1496 .obj_cmpfn = xfrm_pol_bin_cmp, 1497 .automatic_shrinking = true, 1498 }; 1499 1500 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1501 struct xfrm_policy *policy) 1502 { 1503 struct xfrm_policy *pol, *delpol = NULL; 1504 struct hlist_node *newpos = NULL; 1505 int i = 0; 1506 1507 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1508 if (pol->type == policy->type && 1509 pol->if_id == policy->if_id && 1510 !selector_cmp(&pol->selector, &policy->selector) && 1511 xfrm_policy_mark_match(policy, pol) && 1512 xfrm_sec_ctx_match(pol->security, policy->security) && 1513 !WARN_ON(delpol)) { 1514 delpol = pol; 1515 if (policy->priority > pol->priority) 1516 continue; 1517 } else if (policy->priority >= pol->priority) { 1518 newpos = &pol->bydst_inexact_list; 1519 continue; 1520 } 1521 if (delpol) 1522 break; 1523 } 1524 1525 if (newpos) 1526 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1527 else 1528 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1529 1530 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1531 pol->pos = i; 1532 i++; 1533 } 1534 } 1535 1536 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1537 struct xfrm_policy *policy, 1538 bool excl) 1539 { 1540 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1541 1542 hlist_for_each_entry(pol, chain, bydst) { 1543 if (pol->type == policy->type && 1544 pol->if_id == policy->if_id && 1545 !selector_cmp(&pol->selector, &policy->selector) && 1546 xfrm_policy_mark_match(policy, pol) && 1547 xfrm_sec_ctx_match(pol->security, policy->security) && 1548 !WARN_ON(delpol)) { 1549 if (excl) 1550 return ERR_PTR(-EEXIST); 1551 delpol = pol; 1552 if (policy->priority > pol->priority) 1553 continue; 1554 } else if (policy->priority >= pol->priority) { 1555 newpos = pol; 1556 continue; 1557 } 1558 if (delpol) 1559 break; 1560 } 1561 1562 if (newpos) 1563 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1564 else 1565 hlist_add_head_rcu(&policy->bydst, chain); 1566 1567 return delpol; 1568 } 1569 1570 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1571 { 1572 struct net *net = xp_net(policy); 1573 struct xfrm_policy *delpol; 1574 struct hlist_head *chain; 1575 1576 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1577 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1578 if (chain) 1579 delpol = xfrm_policy_insert_list(chain, policy, excl); 1580 else 1581 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1582 1583 if (IS_ERR(delpol)) { 1584 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1585 return PTR_ERR(delpol); 1586 } 1587 1588 __xfrm_policy_link(policy, dir); 1589 1590 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1591 if (policy->family == AF_INET) 1592 rt_genid_bump_ipv4(net); 1593 else 1594 rt_genid_bump_ipv6(net); 1595 1596 if (delpol) { 1597 xfrm_policy_requeue(delpol, policy); 1598 __xfrm_policy_unlink(delpol, dir); 1599 } 1600 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1601 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1602 policy->curlft.add_time = ktime_get_real_seconds(); 1603 policy->curlft.use_time = 0; 1604 if (!mod_timer(&policy->timer, jiffies + HZ)) 1605 xfrm_pol_hold(policy); 1606 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1607 1608 if (delpol) 1609 xfrm_policy_kill(delpol); 1610 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1611 schedule_work(&net->xfrm.policy_hash_work); 1612 1613 return 0; 1614 } 1615 EXPORT_SYMBOL(xfrm_policy_insert); 1616 1617 static struct xfrm_policy * 1618 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id, 1619 u8 type, int dir, 1620 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 (mark & pol->mark.m) == pol->mark.v && 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 *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id, 1641 u8 type, int dir, 1642 struct xfrm_selector *sel, 1643 struct xfrm_sec_ctx *ctx, int delete, 1644 int *err) 1645 { 1646 struct xfrm_pol_inexact_bin *bin = NULL; 1647 struct xfrm_policy *pol, *ret = NULL; 1648 struct hlist_head *chain; 1649 1650 *err = 0; 1651 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1652 chain = policy_hash_bysel(net, sel, sel->family, dir); 1653 if (!chain) { 1654 struct xfrm_pol_inexact_candidates cand; 1655 int i; 1656 1657 bin = xfrm_policy_inexact_lookup(net, type, 1658 sel->family, dir, if_id); 1659 if (!bin) { 1660 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1661 return NULL; 1662 } 1663 1664 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1665 &sel->saddr, 1666 &sel->daddr)) { 1667 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1668 return NULL; 1669 } 1670 1671 pol = NULL; 1672 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1673 struct xfrm_policy *tmp; 1674 1675 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1676 if_id, type, dir, 1677 sel, ctx); 1678 if (!tmp) 1679 continue; 1680 1681 if (!pol || tmp->pos < pol->pos) 1682 pol = tmp; 1683 } 1684 } else { 1685 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1686 sel, ctx); 1687 } 1688 1689 if (pol) { 1690 xfrm_pol_hold(pol); 1691 if (delete) { 1692 *err = security_xfrm_policy_delete(pol->security); 1693 if (*err) { 1694 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1695 return pol; 1696 } 1697 __xfrm_policy_unlink(pol, dir); 1698 } 1699 ret = pol; 1700 } 1701 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1702 1703 if (ret && delete) 1704 xfrm_policy_kill(ret); 1705 if (bin && delete) 1706 xfrm_policy_inexact_prune_bin(bin); 1707 return ret; 1708 } 1709 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1710 1711 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id, 1712 u8 type, int dir, u32 id, int delete, 1713 int *err) 1714 { 1715 struct xfrm_policy *pol, *ret; 1716 struct hlist_head *chain; 1717 1718 *err = -ENOENT; 1719 if (xfrm_policy_id2dir(id) != dir) 1720 return NULL; 1721 1722 *err = 0; 1723 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1724 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1725 ret = NULL; 1726 hlist_for_each_entry(pol, chain, byidx) { 1727 if (pol->type == type && pol->index == id && 1728 pol->if_id == if_id && 1729 (mark & pol->mark.m) == pol->mark.v) { 1730 xfrm_pol_hold(pol); 1731 if (delete) { 1732 *err = security_xfrm_policy_delete( 1733 pol->security); 1734 if (*err) { 1735 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1736 return pol; 1737 } 1738 __xfrm_policy_unlink(pol, dir); 1739 } 1740 ret = pol; 1741 break; 1742 } 1743 } 1744 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1745 1746 if (ret && delete) 1747 xfrm_policy_kill(ret); 1748 return ret; 1749 } 1750 EXPORT_SYMBOL(xfrm_policy_byid); 1751 1752 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1753 static inline int 1754 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1755 { 1756 struct xfrm_policy *pol; 1757 int err = 0; 1758 1759 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1760 if (pol->walk.dead || 1761 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1762 pol->type != type) 1763 continue; 1764 1765 err = security_xfrm_policy_delete(pol->security); 1766 if (err) { 1767 xfrm_audit_policy_delete(pol, 0, task_valid); 1768 return err; 1769 } 1770 } 1771 return err; 1772 } 1773 #else 1774 static inline int 1775 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1776 { 1777 return 0; 1778 } 1779 #endif 1780 1781 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1782 { 1783 int dir, err = 0, cnt = 0; 1784 struct xfrm_policy *pol; 1785 1786 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1787 1788 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1789 if (err) 1790 goto out; 1791 1792 again: 1793 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1794 dir = xfrm_policy_id2dir(pol->index); 1795 if (pol->walk.dead || 1796 dir >= XFRM_POLICY_MAX || 1797 pol->type != type) 1798 continue; 1799 1800 __xfrm_policy_unlink(pol, dir); 1801 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1802 cnt++; 1803 xfrm_audit_policy_delete(pol, 1, task_valid); 1804 xfrm_policy_kill(pol); 1805 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1806 goto again; 1807 } 1808 if (cnt) 1809 __xfrm_policy_inexact_flush(net); 1810 else 1811 err = -ESRCH; 1812 out: 1813 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1814 return err; 1815 } 1816 EXPORT_SYMBOL(xfrm_policy_flush); 1817 1818 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1819 int (*func)(struct xfrm_policy *, int, int, void*), 1820 void *data) 1821 { 1822 struct xfrm_policy *pol; 1823 struct xfrm_policy_walk_entry *x; 1824 int error = 0; 1825 1826 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1827 walk->type != XFRM_POLICY_TYPE_ANY) 1828 return -EINVAL; 1829 1830 if (list_empty(&walk->walk.all) && walk->seq != 0) 1831 return 0; 1832 1833 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1834 if (list_empty(&walk->walk.all)) 1835 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1836 else 1837 x = list_first_entry(&walk->walk.all, 1838 struct xfrm_policy_walk_entry, all); 1839 1840 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1841 if (x->dead) 1842 continue; 1843 pol = container_of(x, struct xfrm_policy, walk); 1844 if (walk->type != XFRM_POLICY_TYPE_ANY && 1845 walk->type != pol->type) 1846 continue; 1847 error = func(pol, xfrm_policy_id2dir(pol->index), 1848 walk->seq, data); 1849 if (error) { 1850 list_move_tail(&walk->walk.all, &x->all); 1851 goto out; 1852 } 1853 walk->seq++; 1854 } 1855 if (walk->seq == 0) { 1856 error = -ENOENT; 1857 goto out; 1858 } 1859 list_del_init(&walk->walk.all); 1860 out: 1861 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1862 return error; 1863 } 1864 EXPORT_SYMBOL(xfrm_policy_walk); 1865 1866 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1867 { 1868 INIT_LIST_HEAD(&walk->walk.all); 1869 walk->walk.dead = 1; 1870 walk->type = type; 1871 walk->seq = 0; 1872 } 1873 EXPORT_SYMBOL(xfrm_policy_walk_init); 1874 1875 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1876 { 1877 if (list_empty(&walk->walk.all)) 1878 return; 1879 1880 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1881 list_del(&walk->walk.all); 1882 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1883 } 1884 EXPORT_SYMBOL(xfrm_policy_walk_done); 1885 1886 /* 1887 * Find policy to apply to this flow. 1888 * 1889 * Returns 0 if policy found, else an -errno. 1890 */ 1891 static int xfrm_policy_match(const struct xfrm_policy *pol, 1892 const struct flowi *fl, 1893 u8 type, u16 family, int dir, u32 if_id) 1894 { 1895 const struct xfrm_selector *sel = &pol->selector; 1896 int ret = -ESRCH; 1897 bool match; 1898 1899 if (pol->family != family || 1900 pol->if_id != if_id || 1901 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1902 pol->type != type) 1903 return ret; 1904 1905 match = xfrm_selector_match(sel, fl, family); 1906 if (match) 1907 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1908 dir); 1909 return ret; 1910 } 1911 1912 static struct xfrm_pol_inexact_node * 1913 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1914 seqcount_t *count, 1915 const xfrm_address_t *addr, u16 family) 1916 { 1917 const struct rb_node *parent; 1918 int seq; 1919 1920 again: 1921 seq = read_seqcount_begin(count); 1922 1923 parent = rcu_dereference_raw(r->rb_node); 1924 while (parent) { 1925 struct xfrm_pol_inexact_node *node; 1926 int delta; 1927 1928 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1929 1930 delta = xfrm_policy_addr_delta(addr, &node->addr, 1931 node->prefixlen, family); 1932 if (delta < 0) { 1933 parent = rcu_dereference_raw(parent->rb_left); 1934 continue; 1935 } else if (delta > 0) { 1936 parent = rcu_dereference_raw(parent->rb_right); 1937 continue; 1938 } 1939 1940 return node; 1941 } 1942 1943 if (read_seqcount_retry(count, seq)) 1944 goto again; 1945 1946 return NULL; 1947 } 1948 1949 static bool 1950 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1951 struct xfrm_pol_inexact_bin *b, 1952 const xfrm_address_t *saddr, 1953 const xfrm_address_t *daddr) 1954 { 1955 struct xfrm_pol_inexact_node *n; 1956 u16 family; 1957 1958 if (!b) 1959 return false; 1960 1961 family = b->k.family; 1962 memset(cand, 0, sizeof(*cand)); 1963 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1964 1965 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1966 family); 1967 if (n) { 1968 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1969 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1970 family); 1971 if (n) 1972 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1973 } 1974 1975 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1976 family); 1977 if (n) 1978 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1979 1980 return true; 1981 } 1982 1983 static struct xfrm_pol_inexact_bin * 1984 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1985 u8 dir, u32 if_id) 1986 { 1987 struct xfrm_pol_inexact_key k = { 1988 .family = family, 1989 .type = type, 1990 .dir = dir, 1991 .if_id = if_id, 1992 }; 1993 1994 write_pnet(&k.net, net); 1995 1996 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1997 xfrm_pol_inexact_params); 1998 } 1999 2000 static struct xfrm_pol_inexact_bin * 2001 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 2002 u8 dir, u32 if_id) 2003 { 2004 struct xfrm_pol_inexact_bin *bin; 2005 2006 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2007 2008 rcu_read_lock(); 2009 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2010 rcu_read_unlock(); 2011 2012 return bin; 2013 } 2014 2015 static struct xfrm_policy * 2016 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2017 struct xfrm_policy *prefer, 2018 const struct flowi *fl, 2019 u8 type, u16 family, int dir, u32 if_id) 2020 { 2021 u32 priority = prefer ? prefer->priority : ~0u; 2022 struct xfrm_policy *pol; 2023 2024 if (!chain) 2025 return NULL; 2026 2027 hlist_for_each_entry_rcu(pol, chain, bydst) { 2028 int err; 2029 2030 if (pol->priority > priority) 2031 break; 2032 2033 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2034 if (err) { 2035 if (err != -ESRCH) 2036 return ERR_PTR(err); 2037 2038 continue; 2039 } 2040 2041 if (prefer) { 2042 /* matches. Is it older than *prefer? */ 2043 if (pol->priority == priority && 2044 prefer->pos < pol->pos) 2045 return prefer; 2046 } 2047 2048 return pol; 2049 } 2050 2051 return NULL; 2052 } 2053 2054 static struct xfrm_policy * 2055 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2056 struct xfrm_policy *prefer, 2057 const struct flowi *fl, 2058 u8 type, u16 family, int dir, u32 if_id) 2059 { 2060 struct xfrm_policy *tmp; 2061 int i; 2062 2063 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2064 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2065 prefer, 2066 fl, type, family, dir, 2067 if_id); 2068 if (!tmp) 2069 continue; 2070 2071 if (IS_ERR(tmp)) 2072 return tmp; 2073 prefer = tmp; 2074 } 2075 2076 return prefer; 2077 } 2078 2079 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2080 const struct flowi *fl, 2081 u16 family, u8 dir, 2082 u32 if_id) 2083 { 2084 struct xfrm_pol_inexact_candidates cand; 2085 const xfrm_address_t *daddr, *saddr; 2086 struct xfrm_pol_inexact_bin *bin; 2087 struct xfrm_policy *pol, *ret; 2088 struct hlist_head *chain; 2089 unsigned int sequence; 2090 int err; 2091 2092 daddr = xfrm_flowi_daddr(fl, family); 2093 saddr = xfrm_flowi_saddr(fl, family); 2094 if (unlikely(!daddr || !saddr)) 2095 return NULL; 2096 2097 rcu_read_lock(); 2098 retry: 2099 do { 2100 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 2101 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2102 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 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 goto retry; 2135 2136 if (ret && !xfrm_pol_hold_rcu(ret)) 2137 goto retry; 2138 fail: 2139 rcu_read_unlock(); 2140 2141 return ret; 2142 } 2143 2144 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2145 const struct flowi *fl, 2146 u16 family, u8 dir, u32 if_id) 2147 { 2148 #ifdef CONFIG_XFRM_SUB_POLICY 2149 struct xfrm_policy *pol; 2150 2151 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2152 dir, if_id); 2153 if (pol != NULL) 2154 return pol; 2155 #endif 2156 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2157 dir, if_id); 2158 } 2159 2160 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2161 const struct flowi *fl, 2162 u16 family, u32 if_id) 2163 { 2164 struct xfrm_policy *pol; 2165 2166 rcu_read_lock(); 2167 again: 2168 pol = rcu_dereference(sk->sk_policy[dir]); 2169 if (pol != NULL) { 2170 bool match; 2171 int err = 0; 2172 2173 if (pol->family != family) { 2174 pol = NULL; 2175 goto out; 2176 } 2177 2178 match = xfrm_selector_match(&pol->selector, fl, family); 2179 if (match) { 2180 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2181 pol->if_id != if_id) { 2182 pol = NULL; 2183 goto out; 2184 } 2185 err = security_xfrm_policy_lookup(pol->security, 2186 fl->flowi_secid, 2187 dir); 2188 if (!err) { 2189 if (!xfrm_pol_hold_rcu(pol)) 2190 goto again; 2191 } else if (err == -ESRCH) { 2192 pol = NULL; 2193 } else { 2194 pol = ERR_PTR(err); 2195 } 2196 } else 2197 pol = NULL; 2198 } 2199 out: 2200 rcu_read_unlock(); 2201 return pol; 2202 } 2203 2204 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2205 { 2206 struct net *net = xp_net(pol); 2207 2208 list_add(&pol->walk.all, &net->xfrm.policy_all); 2209 net->xfrm.policy_count[dir]++; 2210 xfrm_pol_hold(pol); 2211 } 2212 2213 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2214 int dir) 2215 { 2216 struct net *net = xp_net(pol); 2217 2218 if (list_empty(&pol->walk.all)) 2219 return NULL; 2220 2221 /* Socket policies are not hashed. */ 2222 if (!hlist_unhashed(&pol->bydst)) { 2223 hlist_del_rcu(&pol->bydst); 2224 hlist_del_init(&pol->bydst_inexact_list); 2225 hlist_del(&pol->byidx); 2226 } 2227 2228 list_del_init(&pol->walk.all); 2229 net->xfrm.policy_count[dir]--; 2230 2231 return pol; 2232 } 2233 2234 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2235 { 2236 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2237 } 2238 2239 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2240 { 2241 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2242 } 2243 2244 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2245 { 2246 struct net *net = xp_net(pol); 2247 2248 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2249 pol = __xfrm_policy_unlink(pol, dir); 2250 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2251 if (pol) { 2252 xfrm_policy_kill(pol); 2253 return 0; 2254 } 2255 return -ENOENT; 2256 } 2257 EXPORT_SYMBOL(xfrm_policy_delete); 2258 2259 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2260 { 2261 struct net *net = sock_net(sk); 2262 struct xfrm_policy *old_pol; 2263 2264 #ifdef CONFIG_XFRM_SUB_POLICY 2265 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2266 return -EINVAL; 2267 #endif 2268 2269 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2270 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2271 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2272 if (pol) { 2273 pol->curlft.add_time = ktime_get_real_seconds(); 2274 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2275 xfrm_sk_policy_link(pol, dir); 2276 } 2277 rcu_assign_pointer(sk->sk_policy[dir], pol); 2278 if (old_pol) { 2279 if (pol) 2280 xfrm_policy_requeue(old_pol, pol); 2281 2282 /* Unlinking succeeds always. This is the only function 2283 * allowed to delete or replace socket policy. 2284 */ 2285 xfrm_sk_policy_unlink(old_pol, dir); 2286 } 2287 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2288 2289 if (old_pol) { 2290 xfrm_policy_kill(old_pol); 2291 } 2292 return 0; 2293 } 2294 2295 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2296 { 2297 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2298 struct net *net = xp_net(old); 2299 2300 if (newp) { 2301 newp->selector = old->selector; 2302 if (security_xfrm_policy_clone(old->security, 2303 &newp->security)) { 2304 kfree(newp); 2305 return NULL; /* ENOMEM */ 2306 } 2307 newp->lft = old->lft; 2308 newp->curlft = old->curlft; 2309 newp->mark = old->mark; 2310 newp->if_id = old->if_id; 2311 newp->action = old->action; 2312 newp->flags = old->flags; 2313 newp->xfrm_nr = old->xfrm_nr; 2314 newp->index = old->index; 2315 newp->type = old->type; 2316 newp->family = old->family; 2317 memcpy(newp->xfrm_vec, old->xfrm_vec, 2318 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2319 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2320 xfrm_sk_policy_link(newp, dir); 2321 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2322 xfrm_pol_put(newp); 2323 } 2324 return newp; 2325 } 2326 2327 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2328 { 2329 const struct xfrm_policy *p; 2330 struct xfrm_policy *np; 2331 int i, ret = 0; 2332 2333 rcu_read_lock(); 2334 for (i = 0; i < 2; i++) { 2335 p = rcu_dereference(osk->sk_policy[i]); 2336 if (p) { 2337 np = clone_policy(p, i); 2338 if (unlikely(!np)) { 2339 ret = -ENOMEM; 2340 break; 2341 } 2342 rcu_assign_pointer(sk->sk_policy[i], np); 2343 } 2344 } 2345 rcu_read_unlock(); 2346 return ret; 2347 } 2348 2349 static int 2350 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2351 xfrm_address_t *remote, unsigned short family, u32 mark) 2352 { 2353 int err; 2354 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2355 2356 if (unlikely(afinfo == NULL)) 2357 return -EINVAL; 2358 err = afinfo->get_saddr(net, oif, local, remote, mark); 2359 rcu_read_unlock(); 2360 return err; 2361 } 2362 2363 /* Resolve list of templates for the flow, given policy. */ 2364 2365 static int 2366 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2367 struct xfrm_state **xfrm, unsigned short family) 2368 { 2369 struct net *net = xp_net(policy); 2370 int nx; 2371 int i, error; 2372 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2373 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2374 xfrm_address_t tmp; 2375 2376 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2377 struct xfrm_state *x; 2378 xfrm_address_t *remote = daddr; 2379 xfrm_address_t *local = saddr; 2380 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2381 2382 if (tmpl->mode == XFRM_MODE_TUNNEL || 2383 tmpl->mode == XFRM_MODE_BEET) { 2384 remote = &tmpl->id.daddr; 2385 local = &tmpl->saddr; 2386 if (xfrm_addr_any(local, tmpl->encap_family)) { 2387 error = xfrm_get_saddr(net, fl->flowi_oif, 2388 &tmp, remote, 2389 tmpl->encap_family, 0); 2390 if (error) 2391 goto fail; 2392 local = &tmp; 2393 } 2394 } 2395 2396 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2397 family, policy->if_id); 2398 2399 if (x && x->km.state == XFRM_STATE_VALID) { 2400 xfrm[nx++] = x; 2401 daddr = remote; 2402 saddr = local; 2403 continue; 2404 } 2405 if (x) { 2406 error = (x->km.state == XFRM_STATE_ERROR ? 2407 -EINVAL : -EAGAIN); 2408 xfrm_state_put(x); 2409 } else if (error == -ESRCH) { 2410 error = -EAGAIN; 2411 } 2412 2413 if (!tmpl->optional) 2414 goto fail; 2415 } 2416 return nx; 2417 2418 fail: 2419 for (nx--; nx >= 0; nx--) 2420 xfrm_state_put(xfrm[nx]); 2421 return error; 2422 } 2423 2424 static int 2425 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2426 struct xfrm_state **xfrm, unsigned short family) 2427 { 2428 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2429 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2430 int cnx = 0; 2431 int error; 2432 int ret; 2433 int i; 2434 2435 for (i = 0; i < npols; i++) { 2436 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2437 error = -ENOBUFS; 2438 goto fail; 2439 } 2440 2441 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2442 if (ret < 0) { 2443 error = ret; 2444 goto fail; 2445 } else 2446 cnx += ret; 2447 } 2448 2449 /* found states are sorted for outbound processing */ 2450 if (npols > 1) 2451 xfrm_state_sort(xfrm, tpp, cnx, family); 2452 2453 return cnx; 2454 2455 fail: 2456 for (cnx--; cnx >= 0; cnx--) 2457 xfrm_state_put(tpp[cnx]); 2458 return error; 2459 2460 } 2461 2462 static int xfrm_get_tos(const struct flowi *fl, int family) 2463 { 2464 if (family == AF_INET) 2465 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2466 2467 return 0; 2468 } 2469 2470 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2471 { 2472 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2473 struct dst_ops *dst_ops; 2474 struct xfrm_dst *xdst; 2475 2476 if (!afinfo) 2477 return ERR_PTR(-EINVAL); 2478 2479 switch (family) { 2480 case AF_INET: 2481 dst_ops = &net->xfrm.xfrm4_dst_ops; 2482 break; 2483 #if IS_ENABLED(CONFIG_IPV6) 2484 case AF_INET6: 2485 dst_ops = &net->xfrm.xfrm6_dst_ops; 2486 break; 2487 #endif 2488 default: 2489 BUG(); 2490 } 2491 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2492 2493 if (likely(xdst)) { 2494 struct dst_entry *dst = &xdst->u.dst; 2495 2496 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 2497 } else 2498 xdst = ERR_PTR(-ENOBUFS); 2499 2500 rcu_read_unlock(); 2501 2502 return xdst; 2503 } 2504 2505 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2506 int nfheader_len) 2507 { 2508 if (dst->ops->family == AF_INET6) { 2509 struct rt6_info *rt = (struct rt6_info *)dst; 2510 path->path_cookie = rt6_get_cookie(rt); 2511 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2512 } 2513 } 2514 2515 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2516 const struct flowi *fl) 2517 { 2518 const struct xfrm_policy_afinfo *afinfo = 2519 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2520 int err; 2521 2522 if (!afinfo) 2523 return -EINVAL; 2524 2525 err = afinfo->fill_dst(xdst, dev, fl); 2526 2527 rcu_read_unlock(); 2528 2529 return err; 2530 } 2531 2532 2533 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2534 * all the metrics... Shortly, bundle a bundle. 2535 */ 2536 2537 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2538 struct xfrm_state **xfrm, 2539 struct xfrm_dst **bundle, 2540 int nx, 2541 const struct flowi *fl, 2542 struct dst_entry *dst) 2543 { 2544 const struct xfrm_state_afinfo *afinfo; 2545 const struct xfrm_mode *inner_mode; 2546 struct net *net = xp_net(policy); 2547 unsigned long now = jiffies; 2548 struct net_device *dev; 2549 struct xfrm_dst *xdst_prev = NULL; 2550 struct xfrm_dst *xdst0 = NULL; 2551 int i = 0; 2552 int err; 2553 int header_len = 0; 2554 int nfheader_len = 0; 2555 int trailer_len = 0; 2556 int tos; 2557 int family = policy->selector.family; 2558 xfrm_address_t saddr, daddr; 2559 2560 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2561 2562 tos = xfrm_get_tos(fl, family); 2563 2564 dst_hold(dst); 2565 2566 for (; i < nx; i++) { 2567 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2568 struct dst_entry *dst1 = &xdst->u.dst; 2569 2570 err = PTR_ERR(xdst); 2571 if (IS_ERR(xdst)) { 2572 dst_release(dst); 2573 goto put_states; 2574 } 2575 2576 bundle[i] = xdst; 2577 if (!xdst_prev) 2578 xdst0 = xdst; 2579 else 2580 /* Ref count is taken during xfrm_alloc_dst() 2581 * No need to do dst_clone() on dst1 2582 */ 2583 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2584 2585 if (xfrm[i]->sel.family == AF_UNSPEC) { 2586 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2587 xfrm_af2proto(family)); 2588 if (!inner_mode) { 2589 err = -EAFNOSUPPORT; 2590 dst_release(dst); 2591 goto put_states; 2592 } 2593 } else 2594 inner_mode = &xfrm[i]->inner_mode; 2595 2596 xdst->route = dst; 2597 dst_copy_metrics(dst1, dst); 2598 2599 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2600 __u32 mark = 0; 2601 2602 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2603 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2604 2605 family = xfrm[i]->props.family; 2606 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 2607 &saddr, &daddr, family, mark); 2608 err = PTR_ERR(dst); 2609 if (IS_ERR(dst)) 2610 goto put_states; 2611 } else 2612 dst_hold(dst); 2613 2614 dst1->xfrm = xfrm[i]; 2615 xdst->xfrm_genid = xfrm[i]->genid; 2616 2617 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2618 dst1->flags |= DST_HOST; 2619 dst1->lastuse = now; 2620 2621 dst1->input = dst_discard; 2622 2623 rcu_read_lock(); 2624 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2625 if (likely(afinfo)) 2626 dst1->output = afinfo->output; 2627 else 2628 dst1->output = dst_discard_out; 2629 rcu_read_unlock(); 2630 2631 xdst_prev = xdst; 2632 2633 header_len += xfrm[i]->props.header_len; 2634 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2635 nfheader_len += xfrm[i]->props.header_len; 2636 trailer_len += xfrm[i]->props.trailer_len; 2637 } 2638 2639 xfrm_dst_set_child(xdst_prev, dst); 2640 xdst0->path = dst; 2641 2642 err = -ENODEV; 2643 dev = dst->dev; 2644 if (!dev) 2645 goto free_dst; 2646 2647 xfrm_init_path(xdst0, dst, nfheader_len); 2648 xfrm_init_pmtu(bundle, nx); 2649 2650 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2651 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2652 err = xfrm_fill_dst(xdst_prev, dev, fl); 2653 if (err) 2654 goto free_dst; 2655 2656 xdst_prev->u.dst.header_len = header_len; 2657 xdst_prev->u.dst.trailer_len = trailer_len; 2658 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2659 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2660 } 2661 2662 return &xdst0->u.dst; 2663 2664 put_states: 2665 for (; i < nx; i++) 2666 xfrm_state_put(xfrm[i]); 2667 free_dst: 2668 if (xdst0) 2669 dst_release_immediate(&xdst0->u.dst); 2670 2671 return ERR_PTR(err); 2672 } 2673 2674 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2675 struct xfrm_policy **pols, 2676 int *num_pols, int *num_xfrms) 2677 { 2678 int i; 2679 2680 if (*num_pols == 0 || !pols[0]) { 2681 *num_pols = 0; 2682 *num_xfrms = 0; 2683 return 0; 2684 } 2685 if (IS_ERR(pols[0])) 2686 return PTR_ERR(pols[0]); 2687 2688 *num_xfrms = pols[0]->xfrm_nr; 2689 2690 #ifdef CONFIG_XFRM_SUB_POLICY 2691 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 2692 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2693 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2694 XFRM_POLICY_TYPE_MAIN, 2695 fl, family, 2696 XFRM_POLICY_OUT, 2697 pols[0]->if_id); 2698 if (pols[1]) { 2699 if (IS_ERR(pols[1])) { 2700 xfrm_pols_put(pols, *num_pols); 2701 return PTR_ERR(pols[1]); 2702 } 2703 (*num_pols)++; 2704 (*num_xfrms) += pols[1]->xfrm_nr; 2705 } 2706 } 2707 #endif 2708 for (i = 0; i < *num_pols; i++) { 2709 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2710 *num_xfrms = -1; 2711 break; 2712 } 2713 } 2714 2715 return 0; 2716 2717 } 2718 2719 static struct xfrm_dst * 2720 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2721 const struct flowi *fl, u16 family, 2722 struct dst_entry *dst_orig) 2723 { 2724 struct net *net = xp_net(pols[0]); 2725 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2726 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2727 struct xfrm_dst *xdst; 2728 struct dst_entry *dst; 2729 int err; 2730 2731 /* Try to instantiate a bundle */ 2732 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2733 if (err <= 0) { 2734 if (err == 0) 2735 return NULL; 2736 2737 if (err != -EAGAIN) 2738 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2739 return ERR_PTR(err); 2740 } 2741 2742 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2743 if (IS_ERR(dst)) { 2744 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2745 return ERR_CAST(dst); 2746 } 2747 2748 xdst = (struct xfrm_dst *)dst; 2749 xdst->num_xfrms = err; 2750 xdst->num_pols = num_pols; 2751 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2752 xdst->policy_genid = atomic_read(&pols[0]->genid); 2753 2754 return xdst; 2755 } 2756 2757 static void xfrm_policy_queue_process(struct timer_list *t) 2758 { 2759 struct sk_buff *skb; 2760 struct sock *sk; 2761 struct dst_entry *dst; 2762 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2763 struct net *net = xp_net(pol); 2764 struct xfrm_policy_queue *pq = &pol->polq; 2765 struct flowi fl; 2766 struct sk_buff_head list; 2767 2768 spin_lock(&pq->hold_queue.lock); 2769 skb = skb_peek(&pq->hold_queue); 2770 if (!skb) { 2771 spin_unlock(&pq->hold_queue.lock); 2772 goto out; 2773 } 2774 dst = skb_dst(skb); 2775 sk = skb->sk; 2776 xfrm_decode_session(skb, &fl, dst->ops->family); 2777 spin_unlock(&pq->hold_queue.lock); 2778 2779 dst_hold(xfrm_dst_path(dst)); 2780 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2781 if (IS_ERR(dst)) 2782 goto purge_queue; 2783 2784 if (dst->flags & DST_XFRM_QUEUE) { 2785 dst_release(dst); 2786 2787 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2788 goto purge_queue; 2789 2790 pq->timeout = pq->timeout << 1; 2791 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2792 xfrm_pol_hold(pol); 2793 goto out; 2794 } 2795 2796 dst_release(dst); 2797 2798 __skb_queue_head_init(&list); 2799 2800 spin_lock(&pq->hold_queue.lock); 2801 pq->timeout = 0; 2802 skb_queue_splice_init(&pq->hold_queue, &list); 2803 spin_unlock(&pq->hold_queue.lock); 2804 2805 while (!skb_queue_empty(&list)) { 2806 skb = __skb_dequeue(&list); 2807 2808 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2809 dst_hold(xfrm_dst_path(skb_dst(skb))); 2810 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2811 if (IS_ERR(dst)) { 2812 kfree_skb(skb); 2813 continue; 2814 } 2815 2816 nf_reset_ct(skb); 2817 skb_dst_drop(skb); 2818 skb_dst_set(skb, dst); 2819 2820 dst_output(net, skb->sk, skb); 2821 } 2822 2823 out: 2824 xfrm_pol_put(pol); 2825 return; 2826 2827 purge_queue: 2828 pq->timeout = 0; 2829 skb_queue_purge(&pq->hold_queue); 2830 xfrm_pol_put(pol); 2831 } 2832 2833 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2834 { 2835 unsigned long sched_next; 2836 struct dst_entry *dst = skb_dst(skb); 2837 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2838 struct xfrm_policy *pol = xdst->pols[0]; 2839 struct xfrm_policy_queue *pq = &pol->polq; 2840 2841 if (unlikely(skb_fclone_busy(sk, skb))) { 2842 kfree_skb(skb); 2843 return 0; 2844 } 2845 2846 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2847 kfree_skb(skb); 2848 return -EAGAIN; 2849 } 2850 2851 skb_dst_force(skb); 2852 2853 spin_lock_bh(&pq->hold_queue.lock); 2854 2855 if (!pq->timeout) 2856 pq->timeout = XFRM_QUEUE_TMO_MIN; 2857 2858 sched_next = jiffies + pq->timeout; 2859 2860 if (del_timer(&pq->hold_timer)) { 2861 if (time_before(pq->hold_timer.expires, sched_next)) 2862 sched_next = pq->hold_timer.expires; 2863 xfrm_pol_put(pol); 2864 } 2865 2866 __skb_queue_tail(&pq->hold_queue, skb); 2867 if (!mod_timer(&pq->hold_timer, sched_next)) 2868 xfrm_pol_hold(pol); 2869 2870 spin_unlock_bh(&pq->hold_queue.lock); 2871 2872 return 0; 2873 } 2874 2875 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2876 struct xfrm_flo *xflo, 2877 const struct flowi *fl, 2878 int num_xfrms, 2879 u16 family) 2880 { 2881 int err; 2882 struct net_device *dev; 2883 struct dst_entry *dst; 2884 struct dst_entry *dst1; 2885 struct xfrm_dst *xdst; 2886 2887 xdst = xfrm_alloc_dst(net, family); 2888 if (IS_ERR(xdst)) 2889 return xdst; 2890 2891 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2892 net->xfrm.sysctl_larval_drop || 2893 num_xfrms <= 0) 2894 return xdst; 2895 2896 dst = xflo->dst_orig; 2897 dst1 = &xdst->u.dst; 2898 dst_hold(dst); 2899 xdst->route = dst; 2900 2901 dst_copy_metrics(dst1, dst); 2902 2903 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2904 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2905 dst1->lastuse = jiffies; 2906 2907 dst1->input = dst_discard; 2908 dst1->output = xdst_queue_output; 2909 2910 dst_hold(dst); 2911 xfrm_dst_set_child(xdst, dst); 2912 xdst->path = dst; 2913 2914 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2915 2916 err = -ENODEV; 2917 dev = dst->dev; 2918 if (!dev) 2919 goto free_dst; 2920 2921 err = xfrm_fill_dst(xdst, dev, fl); 2922 if (err) 2923 goto free_dst; 2924 2925 out: 2926 return xdst; 2927 2928 free_dst: 2929 dst_release(dst1); 2930 xdst = ERR_PTR(err); 2931 goto out; 2932 } 2933 2934 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2935 const struct flowi *fl, 2936 u16 family, u8 dir, 2937 struct xfrm_flo *xflo, u32 if_id) 2938 { 2939 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2940 int num_pols = 0, num_xfrms = 0, err; 2941 struct xfrm_dst *xdst; 2942 2943 /* Resolve policies to use if we couldn't get them from 2944 * previous cache entry */ 2945 num_pols = 1; 2946 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2947 err = xfrm_expand_policies(fl, family, pols, 2948 &num_pols, &num_xfrms); 2949 if (err < 0) 2950 goto inc_error; 2951 if (num_pols == 0) 2952 return NULL; 2953 if (num_xfrms <= 0) 2954 goto make_dummy_bundle; 2955 2956 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2957 xflo->dst_orig); 2958 if (IS_ERR(xdst)) { 2959 err = PTR_ERR(xdst); 2960 if (err == -EREMOTE) { 2961 xfrm_pols_put(pols, num_pols); 2962 return NULL; 2963 } 2964 2965 if (err != -EAGAIN) 2966 goto error; 2967 goto make_dummy_bundle; 2968 } else if (xdst == NULL) { 2969 num_xfrms = 0; 2970 goto make_dummy_bundle; 2971 } 2972 2973 return xdst; 2974 2975 make_dummy_bundle: 2976 /* We found policies, but there's no bundles to instantiate: 2977 * either because the policy blocks, has no transformations or 2978 * we could not build template (no xfrm_states).*/ 2979 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2980 if (IS_ERR(xdst)) { 2981 xfrm_pols_put(pols, num_pols); 2982 return ERR_CAST(xdst); 2983 } 2984 xdst->num_pols = num_pols; 2985 xdst->num_xfrms = num_xfrms; 2986 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2987 2988 return xdst; 2989 2990 inc_error: 2991 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2992 error: 2993 xfrm_pols_put(pols, num_pols); 2994 return ERR_PTR(err); 2995 } 2996 2997 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2998 struct dst_entry *dst_orig) 2999 { 3000 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 3001 struct dst_entry *ret; 3002 3003 if (!afinfo) { 3004 dst_release(dst_orig); 3005 return ERR_PTR(-EINVAL); 3006 } else { 3007 ret = afinfo->blackhole_route(net, dst_orig); 3008 } 3009 rcu_read_unlock(); 3010 3011 return ret; 3012 } 3013 3014 /* Finds/creates a bundle for given flow and if_id 3015 * 3016 * At the moment we eat a raw IP route. Mostly to speed up lookups 3017 * on interfaces with disabled IPsec. 3018 * 3019 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3020 * compatibility 3021 */ 3022 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3023 struct dst_entry *dst_orig, 3024 const struct flowi *fl, 3025 const struct sock *sk, 3026 int flags, u32 if_id) 3027 { 3028 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3029 struct xfrm_dst *xdst; 3030 struct dst_entry *dst, *route; 3031 u16 family = dst_orig->ops->family; 3032 u8 dir = XFRM_POLICY_OUT; 3033 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3034 3035 dst = NULL; 3036 xdst = NULL; 3037 route = NULL; 3038 3039 sk = sk_const_to_full_sk(sk); 3040 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3041 num_pols = 1; 3042 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3043 if_id); 3044 err = xfrm_expand_policies(fl, family, pols, 3045 &num_pols, &num_xfrms); 3046 if (err < 0) 3047 goto dropdst; 3048 3049 if (num_pols) { 3050 if (num_xfrms <= 0) { 3051 drop_pols = num_pols; 3052 goto no_transform; 3053 } 3054 3055 xdst = xfrm_resolve_and_create_bundle( 3056 pols, num_pols, fl, 3057 family, dst_orig); 3058 3059 if (IS_ERR(xdst)) { 3060 xfrm_pols_put(pols, num_pols); 3061 err = PTR_ERR(xdst); 3062 if (err == -EREMOTE) 3063 goto nopol; 3064 3065 goto dropdst; 3066 } else if (xdst == NULL) { 3067 num_xfrms = 0; 3068 drop_pols = num_pols; 3069 goto no_transform; 3070 } 3071 3072 route = xdst->route; 3073 } 3074 } 3075 3076 if (xdst == NULL) { 3077 struct xfrm_flo xflo; 3078 3079 xflo.dst_orig = dst_orig; 3080 xflo.flags = flags; 3081 3082 /* To accelerate a bit... */ 3083 if ((dst_orig->flags & DST_NOXFRM) || 3084 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 3085 goto nopol; 3086 3087 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3088 if (xdst == NULL) 3089 goto nopol; 3090 if (IS_ERR(xdst)) { 3091 err = PTR_ERR(xdst); 3092 goto dropdst; 3093 } 3094 3095 num_pols = xdst->num_pols; 3096 num_xfrms = xdst->num_xfrms; 3097 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3098 route = xdst->route; 3099 } 3100 3101 dst = &xdst->u.dst; 3102 if (route == NULL && num_xfrms > 0) { 3103 /* The only case when xfrm_bundle_lookup() returns a 3104 * bundle with null route, is when the template could 3105 * not be resolved. It means policies are there, but 3106 * bundle could not be created, since we don't yet 3107 * have the xfrm_state's. We need to wait for KM to 3108 * negotiate new SA's or bail out with error.*/ 3109 if (net->xfrm.sysctl_larval_drop) { 3110 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3111 err = -EREMOTE; 3112 goto error; 3113 } 3114 3115 err = -EAGAIN; 3116 3117 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3118 goto error; 3119 } 3120 3121 no_transform: 3122 if (num_pols == 0) 3123 goto nopol; 3124 3125 if ((flags & XFRM_LOOKUP_ICMP) && 3126 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3127 err = -ENOENT; 3128 goto error; 3129 } 3130 3131 for (i = 0; i < num_pols; i++) 3132 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3133 3134 if (num_xfrms < 0) { 3135 /* Prohibit the flow */ 3136 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3137 err = -EPERM; 3138 goto error; 3139 } else if (num_xfrms > 0) { 3140 /* Flow transformed */ 3141 dst_release(dst_orig); 3142 } else { 3143 /* Flow passes untransformed */ 3144 dst_release(dst); 3145 dst = dst_orig; 3146 } 3147 ok: 3148 xfrm_pols_put(pols, drop_pols); 3149 if (dst && dst->xfrm && 3150 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3151 dst->flags |= DST_XFRM_TUNNEL; 3152 return dst; 3153 3154 nopol: 3155 if (!(flags & XFRM_LOOKUP_ICMP)) { 3156 dst = dst_orig; 3157 goto ok; 3158 } 3159 err = -ENOENT; 3160 error: 3161 dst_release(dst); 3162 dropdst: 3163 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3164 dst_release(dst_orig); 3165 xfrm_pols_put(pols, drop_pols); 3166 return ERR_PTR(err); 3167 } 3168 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3169 3170 /* Main function: finds/creates a bundle for given flow. 3171 * 3172 * At the moment we eat a raw IP route. Mostly to speed up lookups 3173 * on interfaces with disabled IPsec. 3174 */ 3175 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3176 const struct flowi *fl, const struct sock *sk, 3177 int flags) 3178 { 3179 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3180 } 3181 EXPORT_SYMBOL(xfrm_lookup); 3182 3183 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3184 * Otherwise we may send out blackholed packets. 3185 */ 3186 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3187 const struct flowi *fl, 3188 const struct sock *sk, int flags) 3189 { 3190 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3191 flags | XFRM_LOOKUP_QUEUE | 3192 XFRM_LOOKUP_KEEP_DST_REF); 3193 3194 if (PTR_ERR(dst) == -EREMOTE) 3195 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3196 3197 if (IS_ERR(dst)) 3198 dst_release(dst_orig); 3199 3200 return dst; 3201 } 3202 EXPORT_SYMBOL(xfrm_lookup_route); 3203 3204 static inline int 3205 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3206 { 3207 struct sec_path *sp = skb_sec_path(skb); 3208 struct xfrm_state *x; 3209 3210 if (!sp || idx < 0 || idx >= sp->len) 3211 return 0; 3212 x = sp->xvec[idx]; 3213 if (!x->type->reject) 3214 return 0; 3215 return x->type->reject(x, skb, fl); 3216 } 3217 3218 /* When skb is transformed back to its "native" form, we have to 3219 * check policy restrictions. At the moment we make this in maximally 3220 * stupid way. Shame on me. :-) Of course, connected sockets must 3221 * have policy cached at them. 3222 */ 3223 3224 static inline int 3225 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3226 unsigned short family) 3227 { 3228 if (xfrm_state_kern(x)) 3229 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3230 return x->id.proto == tmpl->id.proto && 3231 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3232 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3233 x->props.mode == tmpl->mode && 3234 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3235 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3236 !(x->props.mode != XFRM_MODE_TRANSPORT && 3237 xfrm_state_addr_cmp(tmpl, x, family)); 3238 } 3239 3240 /* 3241 * 0 or more than 0 is returned when validation is succeeded (either bypass 3242 * because of optional transport mode, or next index of the mathced secpath 3243 * state with the template. 3244 * -1 is returned when no matching template is found. 3245 * Otherwise "-2 - errored_index" is returned. 3246 */ 3247 static inline int 3248 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3249 unsigned short family) 3250 { 3251 int idx = start; 3252 3253 if (tmpl->optional) { 3254 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3255 return start; 3256 } else 3257 start = -1; 3258 for (; idx < sp->len; idx++) { 3259 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3260 return ++idx; 3261 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3262 if (start == -1) 3263 start = -2-idx; 3264 break; 3265 } 3266 } 3267 return start; 3268 } 3269 3270 static void 3271 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3272 { 3273 const struct iphdr *iph = ip_hdr(skb); 3274 int ihl = iph->ihl; 3275 u8 *xprth = skb_network_header(skb) + ihl * 4; 3276 struct flowi4 *fl4 = &fl->u.ip4; 3277 int oif = 0; 3278 3279 if (skb_dst(skb) && skb_dst(skb)->dev) 3280 oif = skb_dst(skb)->dev->ifindex; 3281 3282 memset(fl4, 0, sizeof(struct flowi4)); 3283 fl4->flowi4_mark = skb->mark; 3284 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3285 3286 fl4->flowi4_proto = iph->protocol; 3287 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3288 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3289 fl4->flowi4_tos = iph->tos; 3290 3291 if (!ip_is_fragment(iph)) { 3292 switch (iph->protocol) { 3293 case IPPROTO_UDP: 3294 case IPPROTO_UDPLITE: 3295 case IPPROTO_TCP: 3296 case IPPROTO_SCTP: 3297 case IPPROTO_DCCP: 3298 if (xprth + 4 < skb->data || 3299 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3300 __be16 *ports; 3301 3302 xprth = skb_network_header(skb) + ihl * 4; 3303 ports = (__be16 *)xprth; 3304 3305 fl4->fl4_sport = ports[!!reverse]; 3306 fl4->fl4_dport = ports[!reverse]; 3307 } 3308 break; 3309 case IPPROTO_ICMP: 3310 if (xprth + 2 < skb->data || 3311 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3312 u8 *icmp; 3313 3314 xprth = skb_network_header(skb) + ihl * 4; 3315 icmp = xprth; 3316 3317 fl4->fl4_icmp_type = icmp[0]; 3318 fl4->fl4_icmp_code = icmp[1]; 3319 } 3320 break; 3321 case IPPROTO_ESP: 3322 if (xprth + 4 < skb->data || 3323 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3324 __be32 *ehdr; 3325 3326 xprth = skb_network_header(skb) + ihl * 4; 3327 ehdr = (__be32 *)xprth; 3328 3329 fl4->fl4_ipsec_spi = ehdr[0]; 3330 } 3331 break; 3332 case IPPROTO_AH: 3333 if (xprth + 8 < skb->data || 3334 pskb_may_pull(skb, xprth + 8 - skb->data)) { 3335 __be32 *ah_hdr; 3336 3337 xprth = skb_network_header(skb) + ihl * 4; 3338 ah_hdr = (__be32 *)xprth; 3339 3340 fl4->fl4_ipsec_spi = ah_hdr[1]; 3341 } 3342 break; 3343 case IPPROTO_COMP: 3344 if (xprth + 4 < skb->data || 3345 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3346 __be16 *ipcomp_hdr; 3347 3348 xprth = skb_network_header(skb) + ihl * 4; 3349 ipcomp_hdr = (__be16 *)xprth; 3350 3351 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); 3352 } 3353 break; 3354 case IPPROTO_GRE: 3355 if (xprth + 12 < skb->data || 3356 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3357 __be16 *greflags; 3358 __be32 *gre_hdr; 3359 3360 xprth = skb_network_header(skb) + ihl * 4; 3361 greflags = (__be16 *)xprth; 3362 gre_hdr = (__be32 *)xprth; 3363 3364 if (greflags[0] & GRE_KEY) { 3365 if (greflags[0] & GRE_CSUM) 3366 gre_hdr++; 3367 fl4->fl4_gre_key = gre_hdr[1]; 3368 } 3369 } 3370 break; 3371 default: 3372 fl4->fl4_ipsec_spi = 0; 3373 break; 3374 } 3375 } 3376 } 3377 3378 #if IS_ENABLED(CONFIG_IPV6) 3379 static void 3380 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3381 { 3382 struct flowi6 *fl6 = &fl->u.ip6; 3383 int onlyproto = 0; 3384 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3385 u32 offset = sizeof(*hdr); 3386 struct ipv6_opt_hdr *exthdr; 3387 const unsigned char *nh = skb_network_header(skb); 3388 u16 nhoff = IP6CB(skb)->nhoff; 3389 int oif = 0; 3390 u8 nexthdr; 3391 3392 if (!nhoff) 3393 nhoff = offsetof(struct ipv6hdr, nexthdr); 3394 3395 nexthdr = nh[nhoff]; 3396 3397 if (skb_dst(skb) && skb_dst(skb)->dev) 3398 oif = skb_dst(skb)->dev->ifindex; 3399 3400 memset(fl6, 0, sizeof(struct flowi6)); 3401 fl6->flowi6_mark = skb->mark; 3402 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3403 3404 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3405 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3406 3407 while (nh + offset + sizeof(*exthdr) < skb->data || 3408 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3409 nh = skb_network_header(skb); 3410 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3411 3412 switch (nexthdr) { 3413 case NEXTHDR_FRAGMENT: 3414 onlyproto = 1; 3415 /* fall through */ 3416 case NEXTHDR_ROUTING: 3417 case NEXTHDR_HOP: 3418 case NEXTHDR_DEST: 3419 offset += ipv6_optlen(exthdr); 3420 nexthdr = exthdr->nexthdr; 3421 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3422 break; 3423 case IPPROTO_UDP: 3424 case IPPROTO_UDPLITE: 3425 case IPPROTO_TCP: 3426 case IPPROTO_SCTP: 3427 case IPPROTO_DCCP: 3428 if (!onlyproto && (nh + offset + 4 < skb->data || 3429 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3430 __be16 *ports; 3431 3432 nh = skb_network_header(skb); 3433 ports = (__be16 *)(nh + offset); 3434 fl6->fl6_sport = ports[!!reverse]; 3435 fl6->fl6_dport = ports[!reverse]; 3436 } 3437 fl6->flowi6_proto = nexthdr; 3438 return; 3439 case IPPROTO_ICMPV6: 3440 if (!onlyproto && (nh + offset + 2 < skb->data || 3441 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3442 u8 *icmp; 3443 3444 nh = skb_network_header(skb); 3445 icmp = (u8 *)(nh + offset); 3446 fl6->fl6_icmp_type = icmp[0]; 3447 fl6->fl6_icmp_code = icmp[1]; 3448 } 3449 fl6->flowi6_proto = nexthdr; 3450 return; 3451 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3452 case IPPROTO_MH: 3453 offset += ipv6_optlen(exthdr); 3454 if (!onlyproto && (nh + offset + 3 < skb->data || 3455 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3456 struct ip6_mh *mh; 3457 3458 nh = skb_network_header(skb); 3459 mh = (struct ip6_mh *)(nh + offset); 3460 fl6->fl6_mh_type = mh->ip6mh_type; 3461 } 3462 fl6->flowi6_proto = nexthdr; 3463 return; 3464 #endif 3465 /* XXX Why are there these headers? */ 3466 case IPPROTO_AH: 3467 case IPPROTO_ESP: 3468 case IPPROTO_COMP: 3469 default: 3470 fl6->fl6_ipsec_spi = 0; 3471 fl6->flowi6_proto = nexthdr; 3472 return; 3473 } 3474 } 3475 } 3476 #endif 3477 3478 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3479 unsigned int family, int reverse) 3480 { 3481 switch (family) { 3482 case AF_INET: 3483 decode_session4(skb, fl, reverse); 3484 break; 3485 #if IS_ENABLED(CONFIG_IPV6) 3486 case AF_INET6: 3487 decode_session6(skb, fl, reverse); 3488 break; 3489 #endif 3490 default: 3491 return -EAFNOSUPPORT; 3492 } 3493 3494 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3495 } 3496 EXPORT_SYMBOL(__xfrm_decode_session); 3497 3498 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3499 { 3500 for (; k < sp->len; k++) { 3501 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3502 *idxp = k; 3503 return 1; 3504 } 3505 } 3506 3507 return 0; 3508 } 3509 3510 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3511 unsigned short family) 3512 { 3513 struct net *net = dev_net(skb->dev); 3514 struct xfrm_policy *pol; 3515 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3516 int npols = 0; 3517 int xfrm_nr; 3518 int pi; 3519 int reverse; 3520 struct flowi fl; 3521 int xerr_idx = -1; 3522 const struct xfrm_if_cb *ifcb; 3523 struct sec_path *sp; 3524 struct xfrm_if *xi; 3525 u32 if_id = 0; 3526 3527 rcu_read_lock(); 3528 ifcb = xfrm_if_get_cb(); 3529 3530 if (ifcb) { 3531 xi = ifcb->decode_session(skb, family); 3532 if (xi) { 3533 if_id = xi->p.if_id; 3534 net = xi->net; 3535 } 3536 } 3537 rcu_read_unlock(); 3538 3539 reverse = dir & ~XFRM_POLICY_MASK; 3540 dir &= XFRM_POLICY_MASK; 3541 3542 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3543 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3544 return 0; 3545 } 3546 3547 nf_nat_decode_session(skb, &fl, family); 3548 3549 /* First, check used SA against their selectors. */ 3550 sp = skb_sec_path(skb); 3551 if (sp) { 3552 int i; 3553 3554 for (i = sp->len - 1; i >= 0; i--) { 3555 struct xfrm_state *x = sp->xvec[i]; 3556 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3557 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3558 return 0; 3559 } 3560 } 3561 } 3562 3563 pol = NULL; 3564 sk = sk_to_full_sk(sk); 3565 if (sk && sk->sk_policy[dir]) { 3566 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3567 if (IS_ERR(pol)) { 3568 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3569 return 0; 3570 } 3571 } 3572 3573 if (!pol) 3574 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3575 3576 if (IS_ERR(pol)) { 3577 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3578 return 0; 3579 } 3580 3581 if (!pol) { 3582 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3583 xfrm_secpath_reject(xerr_idx, skb, &fl); 3584 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3585 return 0; 3586 } 3587 return 1; 3588 } 3589 3590 pol->curlft.use_time = ktime_get_real_seconds(); 3591 3592 pols[0] = pol; 3593 npols++; 3594 #ifdef CONFIG_XFRM_SUB_POLICY 3595 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3596 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3597 &fl, family, 3598 XFRM_POLICY_IN, if_id); 3599 if (pols[1]) { 3600 if (IS_ERR(pols[1])) { 3601 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3602 return 0; 3603 } 3604 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3605 npols++; 3606 } 3607 } 3608 #endif 3609 3610 if (pol->action == XFRM_POLICY_ALLOW) { 3611 static struct sec_path dummy; 3612 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3613 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3614 struct xfrm_tmpl **tpp = tp; 3615 int ti = 0; 3616 int i, k; 3617 3618 sp = skb_sec_path(skb); 3619 if (!sp) 3620 sp = &dummy; 3621 3622 for (pi = 0; pi < npols; pi++) { 3623 if (pols[pi] != pol && 3624 pols[pi]->action != XFRM_POLICY_ALLOW) { 3625 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3626 goto reject; 3627 } 3628 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3629 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3630 goto reject_error; 3631 } 3632 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3633 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3634 } 3635 xfrm_nr = ti; 3636 if (npols > 1) { 3637 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3638 tpp = stp; 3639 } 3640 3641 /* For each tunnel xfrm, find the first matching tmpl. 3642 * For each tmpl before that, find corresponding xfrm. 3643 * Order is _important_. Later we will implement 3644 * some barriers, but at the moment barriers 3645 * are implied between each two transformations. 3646 */ 3647 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3648 k = xfrm_policy_ok(tpp[i], sp, k, family); 3649 if (k < 0) { 3650 if (k < -1) 3651 /* "-2 - errored_index" returned */ 3652 xerr_idx = -(2+k); 3653 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3654 goto reject; 3655 } 3656 } 3657 3658 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3659 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3660 goto reject; 3661 } 3662 3663 xfrm_pols_put(pols, npols); 3664 return 1; 3665 } 3666 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3667 3668 reject: 3669 xfrm_secpath_reject(xerr_idx, skb, &fl); 3670 reject_error: 3671 xfrm_pols_put(pols, npols); 3672 return 0; 3673 } 3674 EXPORT_SYMBOL(__xfrm_policy_check); 3675 3676 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3677 { 3678 struct net *net = dev_net(skb->dev); 3679 struct flowi fl; 3680 struct dst_entry *dst; 3681 int res = 1; 3682 3683 if (xfrm_decode_session(skb, &fl, family) < 0) { 3684 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3685 return 0; 3686 } 3687 3688 skb_dst_force(skb); 3689 if (!skb_dst(skb)) { 3690 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3691 return 0; 3692 } 3693 3694 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3695 if (IS_ERR(dst)) { 3696 res = 0; 3697 dst = NULL; 3698 } 3699 skb_dst_set(skb, dst); 3700 return res; 3701 } 3702 EXPORT_SYMBOL(__xfrm_route_forward); 3703 3704 /* Optimize later using cookies and generation ids. */ 3705 3706 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3707 { 3708 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3709 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3710 * get validated by dst_ops->check on every use. We do this 3711 * because when a normal route referenced by an XFRM dst is 3712 * obsoleted we do not go looking around for all parent 3713 * referencing XFRM dsts so that we can invalidate them. It 3714 * is just too much work. Instead we make the checks here on 3715 * every use. For example: 3716 * 3717 * XFRM dst A --> IPv4 dst X 3718 * 3719 * X is the "xdst->route" of A (X is also the "dst->path" of A 3720 * in this example). If X is marked obsolete, "A" will not 3721 * notice. That's what we are validating here via the 3722 * stale_bundle() check. 3723 * 3724 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3725 * be marked on it. 3726 * This will force stale_bundle() to fail on any xdst bundle with 3727 * this dst linked in it. 3728 */ 3729 if (dst->obsolete < 0 && !stale_bundle(dst)) 3730 return dst; 3731 3732 return NULL; 3733 } 3734 3735 static int stale_bundle(struct dst_entry *dst) 3736 { 3737 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3738 } 3739 3740 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3741 { 3742 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3743 dst->dev = dev_net(dev)->loopback_dev; 3744 dev_hold(dst->dev); 3745 dev_put(dev); 3746 } 3747 } 3748 EXPORT_SYMBOL(xfrm_dst_ifdown); 3749 3750 static void xfrm_link_failure(struct sk_buff *skb) 3751 { 3752 /* Impossible. Such dst must be popped before reaches point of failure. */ 3753 } 3754 3755 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3756 { 3757 if (dst) { 3758 if (dst->obsolete) { 3759 dst_release(dst); 3760 dst = NULL; 3761 } 3762 } 3763 return dst; 3764 } 3765 3766 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3767 { 3768 while (nr--) { 3769 struct xfrm_dst *xdst = bundle[nr]; 3770 u32 pmtu, route_mtu_cached; 3771 struct dst_entry *dst; 3772 3773 dst = &xdst->u.dst; 3774 pmtu = dst_mtu(xfrm_dst_child(dst)); 3775 xdst->child_mtu_cached = pmtu; 3776 3777 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3778 3779 route_mtu_cached = dst_mtu(xdst->route); 3780 xdst->route_mtu_cached = route_mtu_cached; 3781 3782 if (pmtu > route_mtu_cached) 3783 pmtu = route_mtu_cached; 3784 3785 dst_metric_set(dst, RTAX_MTU, pmtu); 3786 } 3787 } 3788 3789 /* Check that the bundle accepts the flow and its components are 3790 * still valid. 3791 */ 3792 3793 static int xfrm_bundle_ok(struct xfrm_dst *first) 3794 { 3795 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3796 struct dst_entry *dst = &first->u.dst; 3797 struct xfrm_dst *xdst; 3798 int start_from, nr; 3799 u32 mtu; 3800 3801 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3802 (dst->dev && !netif_running(dst->dev))) 3803 return 0; 3804 3805 if (dst->flags & DST_XFRM_QUEUE) 3806 return 1; 3807 3808 start_from = nr = 0; 3809 do { 3810 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3811 3812 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3813 return 0; 3814 if (xdst->xfrm_genid != dst->xfrm->genid) 3815 return 0; 3816 if (xdst->num_pols > 0 && 3817 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3818 return 0; 3819 3820 bundle[nr++] = xdst; 3821 3822 mtu = dst_mtu(xfrm_dst_child(dst)); 3823 if (xdst->child_mtu_cached != mtu) { 3824 start_from = nr; 3825 xdst->child_mtu_cached = mtu; 3826 } 3827 3828 if (!dst_check(xdst->route, xdst->route_cookie)) 3829 return 0; 3830 mtu = dst_mtu(xdst->route); 3831 if (xdst->route_mtu_cached != mtu) { 3832 start_from = nr; 3833 xdst->route_mtu_cached = mtu; 3834 } 3835 3836 dst = xfrm_dst_child(dst); 3837 } while (dst->xfrm); 3838 3839 if (likely(!start_from)) 3840 return 1; 3841 3842 xdst = bundle[start_from - 1]; 3843 mtu = xdst->child_mtu_cached; 3844 while (start_from--) { 3845 dst = &xdst->u.dst; 3846 3847 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3848 if (mtu > xdst->route_mtu_cached) 3849 mtu = xdst->route_mtu_cached; 3850 dst_metric_set(dst, RTAX_MTU, mtu); 3851 if (!start_from) 3852 break; 3853 3854 xdst = bundle[start_from - 1]; 3855 xdst->child_mtu_cached = mtu; 3856 } 3857 3858 return 1; 3859 } 3860 3861 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3862 { 3863 return dst_metric_advmss(xfrm_dst_path(dst)); 3864 } 3865 3866 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3867 { 3868 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3869 3870 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3871 } 3872 3873 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3874 const void *daddr) 3875 { 3876 while (dst->xfrm) { 3877 const struct xfrm_state *xfrm = dst->xfrm; 3878 3879 dst = xfrm_dst_child(dst); 3880 3881 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3882 continue; 3883 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3884 daddr = xfrm->coaddr; 3885 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3886 daddr = &xfrm->id.daddr; 3887 } 3888 return daddr; 3889 } 3890 3891 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3892 struct sk_buff *skb, 3893 const void *daddr) 3894 { 3895 const struct dst_entry *path = xfrm_dst_path(dst); 3896 3897 if (!skb) 3898 daddr = xfrm_get_dst_nexthop(dst, daddr); 3899 return path->ops->neigh_lookup(path, skb, daddr); 3900 } 3901 3902 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3903 { 3904 const struct dst_entry *path = xfrm_dst_path(dst); 3905 3906 daddr = xfrm_get_dst_nexthop(dst, daddr); 3907 path->ops->confirm_neigh(path, daddr); 3908 } 3909 3910 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3911 { 3912 int err = 0; 3913 3914 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3915 return -EAFNOSUPPORT; 3916 3917 spin_lock(&xfrm_policy_afinfo_lock); 3918 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3919 err = -EEXIST; 3920 else { 3921 struct dst_ops *dst_ops = afinfo->dst_ops; 3922 if (likely(dst_ops->kmem_cachep == NULL)) 3923 dst_ops->kmem_cachep = xfrm_dst_cache; 3924 if (likely(dst_ops->check == NULL)) 3925 dst_ops->check = xfrm_dst_check; 3926 if (likely(dst_ops->default_advmss == NULL)) 3927 dst_ops->default_advmss = xfrm_default_advmss; 3928 if (likely(dst_ops->mtu == NULL)) 3929 dst_ops->mtu = xfrm_mtu; 3930 if (likely(dst_ops->negative_advice == NULL)) 3931 dst_ops->negative_advice = xfrm_negative_advice; 3932 if (likely(dst_ops->link_failure == NULL)) 3933 dst_ops->link_failure = xfrm_link_failure; 3934 if (likely(dst_ops->neigh_lookup == NULL)) 3935 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3936 if (likely(!dst_ops->confirm_neigh)) 3937 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3938 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3939 } 3940 spin_unlock(&xfrm_policy_afinfo_lock); 3941 3942 return err; 3943 } 3944 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3945 3946 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3947 { 3948 struct dst_ops *dst_ops = afinfo->dst_ops; 3949 int i; 3950 3951 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3952 if (xfrm_policy_afinfo[i] != afinfo) 3953 continue; 3954 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3955 break; 3956 } 3957 3958 synchronize_rcu(); 3959 3960 dst_ops->kmem_cachep = NULL; 3961 dst_ops->check = NULL; 3962 dst_ops->negative_advice = NULL; 3963 dst_ops->link_failure = NULL; 3964 } 3965 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3966 3967 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3968 { 3969 spin_lock(&xfrm_if_cb_lock); 3970 rcu_assign_pointer(xfrm_if_cb, ifcb); 3971 spin_unlock(&xfrm_if_cb_lock); 3972 } 3973 EXPORT_SYMBOL(xfrm_if_register_cb); 3974 3975 void xfrm_if_unregister_cb(void) 3976 { 3977 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3978 synchronize_rcu(); 3979 } 3980 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3981 3982 #ifdef CONFIG_XFRM_STATISTICS 3983 static int __net_init xfrm_statistics_init(struct net *net) 3984 { 3985 int rv; 3986 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3987 if (!net->mib.xfrm_statistics) 3988 return -ENOMEM; 3989 rv = xfrm_proc_init(net); 3990 if (rv < 0) 3991 free_percpu(net->mib.xfrm_statistics); 3992 return rv; 3993 } 3994 3995 static void xfrm_statistics_fini(struct net *net) 3996 { 3997 xfrm_proc_fini(net); 3998 free_percpu(net->mib.xfrm_statistics); 3999 } 4000 #else 4001 static int __net_init xfrm_statistics_init(struct net *net) 4002 { 4003 return 0; 4004 } 4005 4006 static void xfrm_statistics_fini(struct net *net) 4007 { 4008 } 4009 #endif 4010 4011 static int __net_init xfrm_policy_init(struct net *net) 4012 { 4013 unsigned int hmask, sz; 4014 int dir, err; 4015 4016 if (net_eq(net, &init_net)) { 4017 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4018 sizeof(struct xfrm_dst), 4019 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4020 NULL); 4021 err = rhashtable_init(&xfrm_policy_inexact_table, 4022 &xfrm_pol_inexact_params); 4023 BUG_ON(err); 4024 } 4025 4026 hmask = 8 - 1; 4027 sz = (hmask+1) * sizeof(struct hlist_head); 4028 4029 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4030 if (!net->xfrm.policy_byidx) 4031 goto out_byidx; 4032 net->xfrm.policy_idx_hmask = hmask; 4033 4034 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4035 struct xfrm_policy_hash *htab; 4036 4037 net->xfrm.policy_count[dir] = 0; 4038 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4039 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4040 4041 htab = &net->xfrm.policy_bydst[dir]; 4042 htab->table = xfrm_hash_alloc(sz); 4043 if (!htab->table) 4044 goto out_bydst; 4045 htab->hmask = hmask; 4046 htab->dbits4 = 32; 4047 htab->sbits4 = 32; 4048 htab->dbits6 = 128; 4049 htab->sbits6 = 128; 4050 } 4051 net->xfrm.policy_hthresh.lbits4 = 32; 4052 net->xfrm.policy_hthresh.rbits4 = 32; 4053 net->xfrm.policy_hthresh.lbits6 = 128; 4054 net->xfrm.policy_hthresh.rbits6 = 128; 4055 4056 seqlock_init(&net->xfrm.policy_hthresh.lock); 4057 4058 INIT_LIST_HEAD(&net->xfrm.policy_all); 4059 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4060 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4061 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4062 return 0; 4063 4064 out_bydst: 4065 for (dir--; dir >= 0; dir--) { 4066 struct xfrm_policy_hash *htab; 4067 4068 htab = &net->xfrm.policy_bydst[dir]; 4069 xfrm_hash_free(htab->table, sz); 4070 } 4071 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4072 out_byidx: 4073 return -ENOMEM; 4074 } 4075 4076 static void xfrm_policy_fini(struct net *net) 4077 { 4078 struct xfrm_pol_inexact_bin *b, *t; 4079 unsigned int sz; 4080 int dir; 4081 4082 flush_work(&net->xfrm.policy_hash_work); 4083 #ifdef CONFIG_XFRM_SUB_POLICY 4084 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4085 #endif 4086 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4087 4088 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4089 4090 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4091 struct xfrm_policy_hash *htab; 4092 4093 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4094 4095 htab = &net->xfrm.policy_bydst[dir]; 4096 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4097 WARN_ON(!hlist_empty(htab->table)); 4098 xfrm_hash_free(htab->table, sz); 4099 } 4100 4101 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4102 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4103 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4104 4105 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4106 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4107 __xfrm_policy_inexact_prune_bin(b, true); 4108 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4109 } 4110 4111 static int __net_init xfrm_net_init(struct net *net) 4112 { 4113 int rv; 4114 4115 /* Initialize the per-net locks here */ 4116 spin_lock_init(&net->xfrm.xfrm_state_lock); 4117 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4118 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4119 4120 rv = xfrm_statistics_init(net); 4121 if (rv < 0) 4122 goto out_statistics; 4123 rv = xfrm_state_init(net); 4124 if (rv < 0) 4125 goto out_state; 4126 rv = xfrm_policy_init(net); 4127 if (rv < 0) 4128 goto out_policy; 4129 rv = xfrm_sysctl_init(net); 4130 if (rv < 0) 4131 goto out_sysctl; 4132 4133 return 0; 4134 4135 out_sysctl: 4136 xfrm_policy_fini(net); 4137 out_policy: 4138 xfrm_state_fini(net); 4139 out_state: 4140 xfrm_statistics_fini(net); 4141 out_statistics: 4142 return rv; 4143 } 4144 4145 static void __net_exit xfrm_net_exit(struct net *net) 4146 { 4147 xfrm_sysctl_fini(net); 4148 xfrm_policy_fini(net); 4149 xfrm_state_fini(net); 4150 xfrm_statistics_fini(net); 4151 } 4152 4153 static struct pernet_operations __net_initdata xfrm_net_ops = { 4154 .init = xfrm_net_init, 4155 .exit = xfrm_net_exit, 4156 }; 4157 4158 void __init xfrm_init(void) 4159 { 4160 register_pernet_subsys(&xfrm_net_ops); 4161 xfrm_dev_init(); 4162 seqcount_init(&xfrm_policy_hash_generation); 4163 xfrm_input_init(); 4164 4165 #ifdef CONFIG_INET_ESPINTCP 4166 espintcp_init(); 4167 #endif 4168 4169 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4170 synchronize_rcu(); 4171 } 4172 4173 #ifdef CONFIG_AUDITSYSCALL 4174 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4175 struct audit_buffer *audit_buf) 4176 { 4177 struct xfrm_sec_ctx *ctx = xp->security; 4178 struct xfrm_selector *sel = &xp->selector; 4179 4180 if (ctx) 4181 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4182 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4183 4184 switch (sel->family) { 4185 case AF_INET: 4186 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4187 if (sel->prefixlen_s != 32) 4188 audit_log_format(audit_buf, " src_prefixlen=%d", 4189 sel->prefixlen_s); 4190 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4191 if (sel->prefixlen_d != 32) 4192 audit_log_format(audit_buf, " dst_prefixlen=%d", 4193 sel->prefixlen_d); 4194 break; 4195 case AF_INET6: 4196 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4197 if (sel->prefixlen_s != 128) 4198 audit_log_format(audit_buf, " src_prefixlen=%d", 4199 sel->prefixlen_s); 4200 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4201 if (sel->prefixlen_d != 128) 4202 audit_log_format(audit_buf, " dst_prefixlen=%d", 4203 sel->prefixlen_d); 4204 break; 4205 } 4206 } 4207 4208 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4209 { 4210 struct audit_buffer *audit_buf; 4211 4212 audit_buf = xfrm_audit_start("SPD-add"); 4213 if (audit_buf == NULL) 4214 return; 4215 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4216 audit_log_format(audit_buf, " res=%u", result); 4217 xfrm_audit_common_policyinfo(xp, audit_buf); 4218 audit_log_end(audit_buf); 4219 } 4220 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4221 4222 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4223 bool task_valid) 4224 { 4225 struct audit_buffer *audit_buf; 4226 4227 audit_buf = xfrm_audit_start("SPD-delete"); 4228 if (audit_buf == NULL) 4229 return; 4230 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4231 audit_log_format(audit_buf, " res=%u", result); 4232 xfrm_audit_common_policyinfo(xp, audit_buf); 4233 audit_log_end(audit_buf); 4234 } 4235 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4236 #endif 4237 4238 #ifdef CONFIG_XFRM_MIGRATE 4239 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4240 const struct xfrm_selector *sel_tgt) 4241 { 4242 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4243 if (sel_tgt->family == sel_cmp->family && 4244 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4245 sel_cmp->family) && 4246 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4247 sel_cmp->family) && 4248 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4249 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4250 return true; 4251 } 4252 } else { 4253 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4254 return true; 4255 } 4256 } 4257 return false; 4258 } 4259 4260 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4261 u8 dir, u8 type, struct net *net) 4262 { 4263 struct xfrm_policy *pol, *ret = NULL; 4264 struct hlist_head *chain; 4265 u32 priority = ~0U; 4266 4267 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4268 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4269 hlist_for_each_entry(pol, chain, bydst) { 4270 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4271 pol->type == type) { 4272 ret = pol; 4273 priority = ret->priority; 4274 break; 4275 } 4276 } 4277 chain = &net->xfrm.policy_inexact[dir]; 4278 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4279 if ((pol->priority >= priority) && ret) 4280 break; 4281 4282 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4283 pol->type == type) { 4284 ret = pol; 4285 break; 4286 } 4287 } 4288 4289 xfrm_pol_hold(ret); 4290 4291 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4292 4293 return ret; 4294 } 4295 4296 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4297 { 4298 int match = 0; 4299 4300 if (t->mode == m->mode && t->id.proto == m->proto && 4301 (m->reqid == 0 || t->reqid == m->reqid)) { 4302 switch (t->mode) { 4303 case XFRM_MODE_TUNNEL: 4304 case XFRM_MODE_BEET: 4305 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4306 m->old_family) && 4307 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4308 m->old_family)) { 4309 match = 1; 4310 } 4311 break; 4312 case XFRM_MODE_TRANSPORT: 4313 /* in case of transport mode, template does not store 4314 any IP addresses, hence we just compare mode and 4315 protocol */ 4316 match = 1; 4317 break; 4318 default: 4319 break; 4320 } 4321 } 4322 return match; 4323 } 4324 4325 /* update endpoint address(es) of template(s) */ 4326 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4327 struct xfrm_migrate *m, int num_migrate) 4328 { 4329 struct xfrm_migrate *mp; 4330 int i, j, n = 0; 4331 4332 write_lock_bh(&pol->lock); 4333 if (unlikely(pol->walk.dead)) { 4334 /* target policy has been deleted */ 4335 write_unlock_bh(&pol->lock); 4336 return -ENOENT; 4337 } 4338 4339 for (i = 0; i < pol->xfrm_nr; i++) { 4340 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4341 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4342 continue; 4343 n++; 4344 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4345 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4346 continue; 4347 /* update endpoints */ 4348 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4349 sizeof(pol->xfrm_vec[i].id.daddr)); 4350 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4351 sizeof(pol->xfrm_vec[i].saddr)); 4352 pol->xfrm_vec[i].encap_family = mp->new_family; 4353 /* flush bundles */ 4354 atomic_inc(&pol->genid); 4355 } 4356 } 4357 4358 write_unlock_bh(&pol->lock); 4359 4360 if (!n) 4361 return -ENODATA; 4362 4363 return 0; 4364 } 4365 4366 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4367 { 4368 int i, j; 4369 4370 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4371 return -EINVAL; 4372 4373 for (i = 0; i < num_migrate; i++) { 4374 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4375 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4376 return -EINVAL; 4377 4378 /* check if there is any duplicated entry */ 4379 for (j = i + 1; j < num_migrate; j++) { 4380 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4381 sizeof(m[i].old_daddr)) && 4382 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4383 sizeof(m[i].old_saddr)) && 4384 m[i].proto == m[j].proto && 4385 m[i].mode == m[j].mode && 4386 m[i].reqid == m[j].reqid && 4387 m[i].old_family == m[j].old_family) 4388 return -EINVAL; 4389 } 4390 } 4391 4392 return 0; 4393 } 4394 4395 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4396 struct xfrm_migrate *m, int num_migrate, 4397 struct xfrm_kmaddress *k, struct net *net, 4398 struct xfrm_encap_tmpl *encap) 4399 { 4400 int i, err, nx_cur = 0, nx_new = 0; 4401 struct xfrm_policy *pol = NULL; 4402 struct xfrm_state *x, *xc; 4403 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4404 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4405 struct xfrm_migrate *mp; 4406 4407 /* Stage 0 - sanity checks */ 4408 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4409 goto out; 4410 4411 if (dir >= XFRM_POLICY_MAX) { 4412 err = -EINVAL; 4413 goto out; 4414 } 4415 4416 /* Stage 1 - find policy */ 4417 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4418 err = -ENOENT; 4419 goto out; 4420 } 4421 4422 /* Stage 2 - find and update state(s) */ 4423 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4424 if ((x = xfrm_migrate_state_find(mp, net))) { 4425 x_cur[nx_cur] = x; 4426 nx_cur++; 4427 xc = xfrm_state_migrate(x, mp, encap); 4428 if (xc) { 4429 x_new[nx_new] = xc; 4430 nx_new++; 4431 } else { 4432 err = -ENODATA; 4433 goto restore_state; 4434 } 4435 } 4436 } 4437 4438 /* Stage 3 - update policy */ 4439 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4440 goto restore_state; 4441 4442 /* Stage 4 - delete old state(s) */ 4443 if (nx_cur) { 4444 xfrm_states_put(x_cur, nx_cur); 4445 xfrm_states_delete(x_cur, nx_cur); 4446 } 4447 4448 /* Stage 5 - announce */ 4449 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4450 4451 xfrm_pol_put(pol); 4452 4453 return 0; 4454 out: 4455 return err; 4456 4457 restore_state: 4458 if (pol) 4459 xfrm_pol_put(pol); 4460 if (nx_cur) 4461 xfrm_states_put(x_cur, nx_cur); 4462 if (nx_new) 4463 xfrm_states_delete(x_new, nx_new); 4464 4465 return err; 4466 } 4467 EXPORT_SYMBOL(xfrm_migrate); 4468 #endif 4469