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 if (policy->mark.v == pol->mark.v && 1440 policy->priority == pol->priority) 1441 return true; 1442 1443 return false; 1444 } 1445 1446 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1447 { 1448 const struct xfrm_pol_inexact_key *k = data; 1449 u32 a = k->type << 24 | k->dir << 16 | k->family; 1450 1451 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1452 seed); 1453 } 1454 1455 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1456 { 1457 const struct xfrm_pol_inexact_bin *b = data; 1458 1459 return xfrm_pol_bin_key(&b->k, 0, seed); 1460 } 1461 1462 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1463 const void *ptr) 1464 { 1465 const struct xfrm_pol_inexact_key *key = arg->key; 1466 const struct xfrm_pol_inexact_bin *b = ptr; 1467 int ret; 1468 1469 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1470 return -1; 1471 1472 ret = b->k.dir ^ key->dir; 1473 if (ret) 1474 return ret; 1475 1476 ret = b->k.type ^ key->type; 1477 if (ret) 1478 return ret; 1479 1480 ret = b->k.family ^ key->family; 1481 if (ret) 1482 return ret; 1483 1484 return b->k.if_id ^ key->if_id; 1485 } 1486 1487 static const struct rhashtable_params xfrm_pol_inexact_params = { 1488 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1489 .hashfn = xfrm_pol_bin_key, 1490 .obj_hashfn = xfrm_pol_bin_obj, 1491 .obj_cmpfn = xfrm_pol_bin_cmp, 1492 .automatic_shrinking = true, 1493 }; 1494 1495 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1496 struct xfrm_policy *policy) 1497 { 1498 struct xfrm_policy *pol, *delpol = NULL; 1499 struct hlist_node *newpos = NULL; 1500 int i = 0; 1501 1502 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1503 if (pol->type == policy->type && 1504 pol->if_id == policy->if_id && 1505 !selector_cmp(&pol->selector, &policy->selector) && 1506 xfrm_policy_mark_match(policy, pol) && 1507 xfrm_sec_ctx_match(pol->security, policy->security) && 1508 !WARN_ON(delpol)) { 1509 delpol = pol; 1510 if (policy->priority > pol->priority) 1511 continue; 1512 } else if (policy->priority >= pol->priority) { 1513 newpos = &pol->bydst_inexact_list; 1514 continue; 1515 } 1516 if (delpol) 1517 break; 1518 } 1519 1520 if (newpos) 1521 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1522 else 1523 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1524 1525 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1526 pol->pos = i; 1527 i++; 1528 } 1529 } 1530 1531 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1532 struct xfrm_policy *policy, 1533 bool excl) 1534 { 1535 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1536 1537 hlist_for_each_entry(pol, chain, bydst) { 1538 if (pol->type == policy->type && 1539 pol->if_id == policy->if_id && 1540 !selector_cmp(&pol->selector, &policy->selector) && 1541 xfrm_policy_mark_match(policy, pol) && 1542 xfrm_sec_ctx_match(pol->security, policy->security) && 1543 !WARN_ON(delpol)) { 1544 if (excl) 1545 return ERR_PTR(-EEXIST); 1546 delpol = pol; 1547 if (policy->priority > pol->priority) 1548 continue; 1549 } else if (policy->priority >= pol->priority) { 1550 newpos = pol; 1551 continue; 1552 } 1553 if (delpol) 1554 break; 1555 } 1556 1557 if (newpos) 1558 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1559 else 1560 hlist_add_head_rcu(&policy->bydst, chain); 1561 1562 return delpol; 1563 } 1564 1565 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1566 { 1567 struct net *net = xp_net(policy); 1568 struct xfrm_policy *delpol; 1569 struct hlist_head *chain; 1570 1571 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1572 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1573 if (chain) 1574 delpol = xfrm_policy_insert_list(chain, policy, excl); 1575 else 1576 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1577 1578 if (IS_ERR(delpol)) { 1579 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1580 return PTR_ERR(delpol); 1581 } 1582 1583 __xfrm_policy_link(policy, dir); 1584 1585 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1586 if (policy->family == AF_INET) 1587 rt_genid_bump_ipv4(net); 1588 else 1589 rt_genid_bump_ipv6(net); 1590 1591 if (delpol) { 1592 xfrm_policy_requeue(delpol, policy); 1593 __xfrm_policy_unlink(delpol, dir); 1594 } 1595 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1596 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1597 policy->curlft.add_time = ktime_get_real_seconds(); 1598 policy->curlft.use_time = 0; 1599 if (!mod_timer(&policy->timer, jiffies + HZ)) 1600 xfrm_pol_hold(policy); 1601 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1602 1603 if (delpol) 1604 xfrm_policy_kill(delpol); 1605 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1606 schedule_work(&net->xfrm.policy_hash_work); 1607 1608 return 0; 1609 } 1610 EXPORT_SYMBOL(xfrm_policy_insert); 1611 1612 static struct xfrm_policy * 1613 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id, 1614 u8 type, int dir, 1615 struct xfrm_selector *sel, 1616 struct xfrm_sec_ctx *ctx) 1617 { 1618 struct xfrm_policy *pol; 1619 1620 if (!chain) 1621 return NULL; 1622 1623 hlist_for_each_entry(pol, chain, bydst) { 1624 if (pol->type == type && 1625 pol->if_id == if_id && 1626 (mark & pol->mark.m) == pol->mark.v && 1627 !selector_cmp(sel, &pol->selector) && 1628 xfrm_sec_ctx_match(ctx, pol->security)) 1629 return pol; 1630 } 1631 1632 return NULL; 1633 } 1634 1635 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id, 1636 u8 type, int dir, 1637 struct xfrm_selector *sel, 1638 struct xfrm_sec_ctx *ctx, int delete, 1639 int *err) 1640 { 1641 struct xfrm_pol_inexact_bin *bin = NULL; 1642 struct xfrm_policy *pol, *ret = NULL; 1643 struct hlist_head *chain; 1644 1645 *err = 0; 1646 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1647 chain = policy_hash_bysel(net, sel, sel->family, dir); 1648 if (!chain) { 1649 struct xfrm_pol_inexact_candidates cand; 1650 int i; 1651 1652 bin = xfrm_policy_inexact_lookup(net, type, 1653 sel->family, dir, if_id); 1654 if (!bin) { 1655 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1656 return NULL; 1657 } 1658 1659 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1660 &sel->saddr, 1661 &sel->daddr)) { 1662 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1663 return NULL; 1664 } 1665 1666 pol = NULL; 1667 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1668 struct xfrm_policy *tmp; 1669 1670 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1671 if_id, type, dir, 1672 sel, ctx); 1673 if (!tmp) 1674 continue; 1675 1676 if (!pol || tmp->pos < pol->pos) 1677 pol = tmp; 1678 } 1679 } else { 1680 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1681 sel, ctx); 1682 } 1683 1684 if (pol) { 1685 xfrm_pol_hold(pol); 1686 if (delete) { 1687 *err = security_xfrm_policy_delete(pol->security); 1688 if (*err) { 1689 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1690 return pol; 1691 } 1692 __xfrm_policy_unlink(pol, dir); 1693 } 1694 ret = pol; 1695 } 1696 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1697 1698 if (ret && delete) 1699 xfrm_policy_kill(ret); 1700 if (bin && delete) 1701 xfrm_policy_inexact_prune_bin(bin); 1702 return ret; 1703 } 1704 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1705 1706 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id, 1707 u8 type, int dir, u32 id, int delete, 1708 int *err) 1709 { 1710 struct xfrm_policy *pol, *ret; 1711 struct hlist_head *chain; 1712 1713 *err = -ENOENT; 1714 if (xfrm_policy_id2dir(id) != dir) 1715 return NULL; 1716 1717 *err = 0; 1718 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1719 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1720 ret = NULL; 1721 hlist_for_each_entry(pol, chain, byidx) { 1722 if (pol->type == type && pol->index == id && 1723 pol->if_id == if_id && 1724 (mark & pol->mark.m) == pol->mark.v) { 1725 xfrm_pol_hold(pol); 1726 if (delete) { 1727 *err = security_xfrm_policy_delete( 1728 pol->security); 1729 if (*err) { 1730 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1731 return pol; 1732 } 1733 __xfrm_policy_unlink(pol, dir); 1734 } 1735 ret = pol; 1736 break; 1737 } 1738 } 1739 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1740 1741 if (ret && delete) 1742 xfrm_policy_kill(ret); 1743 return ret; 1744 } 1745 EXPORT_SYMBOL(xfrm_policy_byid); 1746 1747 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1748 static inline int 1749 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1750 { 1751 struct xfrm_policy *pol; 1752 int err = 0; 1753 1754 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1755 if (pol->walk.dead || 1756 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1757 pol->type != type) 1758 continue; 1759 1760 err = security_xfrm_policy_delete(pol->security); 1761 if (err) { 1762 xfrm_audit_policy_delete(pol, 0, task_valid); 1763 return err; 1764 } 1765 } 1766 return err; 1767 } 1768 #else 1769 static inline int 1770 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1771 { 1772 return 0; 1773 } 1774 #endif 1775 1776 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1777 { 1778 int dir, err = 0, cnt = 0; 1779 struct xfrm_policy *pol; 1780 1781 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1782 1783 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1784 if (err) 1785 goto out; 1786 1787 again: 1788 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1789 dir = xfrm_policy_id2dir(pol->index); 1790 if (pol->walk.dead || 1791 dir >= XFRM_POLICY_MAX || 1792 pol->type != type) 1793 continue; 1794 1795 __xfrm_policy_unlink(pol, dir); 1796 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1797 cnt++; 1798 xfrm_audit_policy_delete(pol, 1, task_valid); 1799 xfrm_policy_kill(pol); 1800 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1801 goto again; 1802 } 1803 if (cnt) 1804 __xfrm_policy_inexact_flush(net); 1805 else 1806 err = -ESRCH; 1807 out: 1808 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1809 return err; 1810 } 1811 EXPORT_SYMBOL(xfrm_policy_flush); 1812 1813 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1814 int (*func)(struct xfrm_policy *, int, int, void*), 1815 void *data) 1816 { 1817 struct xfrm_policy *pol; 1818 struct xfrm_policy_walk_entry *x; 1819 int error = 0; 1820 1821 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1822 walk->type != XFRM_POLICY_TYPE_ANY) 1823 return -EINVAL; 1824 1825 if (list_empty(&walk->walk.all) && walk->seq != 0) 1826 return 0; 1827 1828 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1829 if (list_empty(&walk->walk.all)) 1830 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1831 else 1832 x = list_first_entry(&walk->walk.all, 1833 struct xfrm_policy_walk_entry, all); 1834 1835 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1836 if (x->dead) 1837 continue; 1838 pol = container_of(x, struct xfrm_policy, walk); 1839 if (walk->type != XFRM_POLICY_TYPE_ANY && 1840 walk->type != pol->type) 1841 continue; 1842 error = func(pol, xfrm_policy_id2dir(pol->index), 1843 walk->seq, data); 1844 if (error) { 1845 list_move_tail(&walk->walk.all, &x->all); 1846 goto out; 1847 } 1848 walk->seq++; 1849 } 1850 if (walk->seq == 0) { 1851 error = -ENOENT; 1852 goto out; 1853 } 1854 list_del_init(&walk->walk.all); 1855 out: 1856 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1857 return error; 1858 } 1859 EXPORT_SYMBOL(xfrm_policy_walk); 1860 1861 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1862 { 1863 INIT_LIST_HEAD(&walk->walk.all); 1864 walk->walk.dead = 1; 1865 walk->type = type; 1866 walk->seq = 0; 1867 } 1868 EXPORT_SYMBOL(xfrm_policy_walk_init); 1869 1870 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1871 { 1872 if (list_empty(&walk->walk.all)) 1873 return; 1874 1875 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1876 list_del(&walk->walk.all); 1877 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1878 } 1879 EXPORT_SYMBOL(xfrm_policy_walk_done); 1880 1881 /* 1882 * Find policy to apply to this flow. 1883 * 1884 * Returns 0 if policy found, else an -errno. 1885 */ 1886 static int xfrm_policy_match(const struct xfrm_policy *pol, 1887 const struct flowi *fl, 1888 u8 type, u16 family, int dir, u32 if_id) 1889 { 1890 const struct xfrm_selector *sel = &pol->selector; 1891 int ret = -ESRCH; 1892 bool match; 1893 1894 if (pol->family != family || 1895 pol->if_id != if_id || 1896 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1897 pol->type != type) 1898 return ret; 1899 1900 match = xfrm_selector_match(sel, fl, family); 1901 if (match) 1902 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1903 dir); 1904 return ret; 1905 } 1906 1907 static struct xfrm_pol_inexact_node * 1908 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1909 seqcount_t *count, 1910 const xfrm_address_t *addr, u16 family) 1911 { 1912 const struct rb_node *parent; 1913 int seq; 1914 1915 again: 1916 seq = read_seqcount_begin(count); 1917 1918 parent = rcu_dereference_raw(r->rb_node); 1919 while (parent) { 1920 struct xfrm_pol_inexact_node *node; 1921 int delta; 1922 1923 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1924 1925 delta = xfrm_policy_addr_delta(addr, &node->addr, 1926 node->prefixlen, family); 1927 if (delta < 0) { 1928 parent = rcu_dereference_raw(parent->rb_left); 1929 continue; 1930 } else if (delta > 0) { 1931 parent = rcu_dereference_raw(parent->rb_right); 1932 continue; 1933 } 1934 1935 return node; 1936 } 1937 1938 if (read_seqcount_retry(count, seq)) 1939 goto again; 1940 1941 return NULL; 1942 } 1943 1944 static bool 1945 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1946 struct xfrm_pol_inexact_bin *b, 1947 const xfrm_address_t *saddr, 1948 const xfrm_address_t *daddr) 1949 { 1950 struct xfrm_pol_inexact_node *n; 1951 u16 family; 1952 1953 if (!b) 1954 return false; 1955 1956 family = b->k.family; 1957 memset(cand, 0, sizeof(*cand)); 1958 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1959 1960 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1961 family); 1962 if (n) { 1963 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1964 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1965 family); 1966 if (n) 1967 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1968 } 1969 1970 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1971 family); 1972 if (n) 1973 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1974 1975 return true; 1976 } 1977 1978 static struct xfrm_pol_inexact_bin * 1979 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1980 u8 dir, u32 if_id) 1981 { 1982 struct xfrm_pol_inexact_key k = { 1983 .family = family, 1984 .type = type, 1985 .dir = dir, 1986 .if_id = if_id, 1987 }; 1988 1989 write_pnet(&k.net, net); 1990 1991 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1992 xfrm_pol_inexact_params); 1993 } 1994 1995 static struct xfrm_pol_inexact_bin * 1996 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 1997 u8 dir, u32 if_id) 1998 { 1999 struct xfrm_pol_inexact_bin *bin; 2000 2001 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2002 2003 rcu_read_lock(); 2004 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2005 rcu_read_unlock(); 2006 2007 return bin; 2008 } 2009 2010 static struct xfrm_policy * 2011 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2012 struct xfrm_policy *prefer, 2013 const struct flowi *fl, 2014 u8 type, u16 family, int dir, u32 if_id) 2015 { 2016 u32 priority = prefer ? prefer->priority : ~0u; 2017 struct xfrm_policy *pol; 2018 2019 if (!chain) 2020 return NULL; 2021 2022 hlist_for_each_entry_rcu(pol, chain, bydst) { 2023 int err; 2024 2025 if (pol->priority > priority) 2026 break; 2027 2028 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2029 if (err) { 2030 if (err != -ESRCH) 2031 return ERR_PTR(err); 2032 2033 continue; 2034 } 2035 2036 if (prefer) { 2037 /* matches. Is it older than *prefer? */ 2038 if (pol->priority == priority && 2039 prefer->pos < pol->pos) 2040 return prefer; 2041 } 2042 2043 return pol; 2044 } 2045 2046 return NULL; 2047 } 2048 2049 static struct xfrm_policy * 2050 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2051 struct xfrm_policy *prefer, 2052 const struct flowi *fl, 2053 u8 type, u16 family, int dir, u32 if_id) 2054 { 2055 struct xfrm_policy *tmp; 2056 int i; 2057 2058 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2059 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2060 prefer, 2061 fl, type, family, dir, 2062 if_id); 2063 if (!tmp) 2064 continue; 2065 2066 if (IS_ERR(tmp)) 2067 return tmp; 2068 prefer = tmp; 2069 } 2070 2071 return prefer; 2072 } 2073 2074 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2075 const struct flowi *fl, 2076 u16 family, u8 dir, 2077 u32 if_id) 2078 { 2079 struct xfrm_pol_inexact_candidates cand; 2080 const xfrm_address_t *daddr, *saddr; 2081 struct xfrm_pol_inexact_bin *bin; 2082 struct xfrm_policy *pol, *ret; 2083 struct hlist_head *chain; 2084 unsigned int sequence; 2085 int err; 2086 2087 daddr = xfrm_flowi_daddr(fl, family); 2088 saddr = xfrm_flowi_saddr(fl, family); 2089 if (unlikely(!daddr || !saddr)) 2090 return NULL; 2091 2092 rcu_read_lock(); 2093 retry: 2094 do { 2095 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 2096 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2097 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 2098 2099 ret = NULL; 2100 hlist_for_each_entry_rcu(pol, chain, bydst) { 2101 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2102 if (err) { 2103 if (err == -ESRCH) 2104 continue; 2105 else { 2106 ret = ERR_PTR(err); 2107 goto fail; 2108 } 2109 } else { 2110 ret = pol; 2111 break; 2112 } 2113 } 2114 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2115 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2116 daddr)) 2117 goto skip_inexact; 2118 2119 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2120 family, dir, if_id); 2121 if (pol) { 2122 ret = pol; 2123 if (IS_ERR(pol)) 2124 goto fail; 2125 } 2126 2127 skip_inexact: 2128 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 2129 goto retry; 2130 2131 if (ret && !xfrm_pol_hold_rcu(ret)) 2132 goto retry; 2133 fail: 2134 rcu_read_unlock(); 2135 2136 return ret; 2137 } 2138 2139 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2140 const struct flowi *fl, 2141 u16 family, u8 dir, u32 if_id) 2142 { 2143 #ifdef CONFIG_XFRM_SUB_POLICY 2144 struct xfrm_policy *pol; 2145 2146 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2147 dir, if_id); 2148 if (pol != NULL) 2149 return pol; 2150 #endif 2151 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2152 dir, if_id); 2153 } 2154 2155 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2156 const struct flowi *fl, 2157 u16 family, u32 if_id) 2158 { 2159 struct xfrm_policy *pol; 2160 2161 rcu_read_lock(); 2162 again: 2163 pol = rcu_dereference(sk->sk_policy[dir]); 2164 if (pol != NULL) { 2165 bool match; 2166 int err = 0; 2167 2168 if (pol->family != family) { 2169 pol = NULL; 2170 goto out; 2171 } 2172 2173 match = xfrm_selector_match(&pol->selector, fl, family); 2174 if (match) { 2175 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2176 pol->if_id != if_id) { 2177 pol = NULL; 2178 goto out; 2179 } 2180 err = security_xfrm_policy_lookup(pol->security, 2181 fl->flowi_secid, 2182 dir); 2183 if (!err) { 2184 if (!xfrm_pol_hold_rcu(pol)) 2185 goto again; 2186 } else if (err == -ESRCH) { 2187 pol = NULL; 2188 } else { 2189 pol = ERR_PTR(err); 2190 } 2191 } else 2192 pol = NULL; 2193 } 2194 out: 2195 rcu_read_unlock(); 2196 return pol; 2197 } 2198 2199 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2200 { 2201 struct net *net = xp_net(pol); 2202 2203 list_add(&pol->walk.all, &net->xfrm.policy_all); 2204 net->xfrm.policy_count[dir]++; 2205 xfrm_pol_hold(pol); 2206 } 2207 2208 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2209 int dir) 2210 { 2211 struct net *net = xp_net(pol); 2212 2213 if (list_empty(&pol->walk.all)) 2214 return NULL; 2215 2216 /* Socket policies are not hashed. */ 2217 if (!hlist_unhashed(&pol->bydst)) { 2218 hlist_del_rcu(&pol->bydst); 2219 hlist_del_init(&pol->bydst_inexact_list); 2220 hlist_del(&pol->byidx); 2221 } 2222 2223 list_del_init(&pol->walk.all); 2224 net->xfrm.policy_count[dir]--; 2225 2226 return pol; 2227 } 2228 2229 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2230 { 2231 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2232 } 2233 2234 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2235 { 2236 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2237 } 2238 2239 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2240 { 2241 struct net *net = xp_net(pol); 2242 2243 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2244 pol = __xfrm_policy_unlink(pol, dir); 2245 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2246 if (pol) { 2247 xfrm_policy_kill(pol); 2248 return 0; 2249 } 2250 return -ENOENT; 2251 } 2252 EXPORT_SYMBOL(xfrm_policy_delete); 2253 2254 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2255 { 2256 struct net *net = sock_net(sk); 2257 struct xfrm_policy *old_pol; 2258 2259 #ifdef CONFIG_XFRM_SUB_POLICY 2260 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2261 return -EINVAL; 2262 #endif 2263 2264 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2265 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2266 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2267 if (pol) { 2268 pol->curlft.add_time = ktime_get_real_seconds(); 2269 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2270 xfrm_sk_policy_link(pol, dir); 2271 } 2272 rcu_assign_pointer(sk->sk_policy[dir], pol); 2273 if (old_pol) { 2274 if (pol) 2275 xfrm_policy_requeue(old_pol, pol); 2276 2277 /* Unlinking succeeds always. This is the only function 2278 * allowed to delete or replace socket policy. 2279 */ 2280 xfrm_sk_policy_unlink(old_pol, dir); 2281 } 2282 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2283 2284 if (old_pol) { 2285 xfrm_policy_kill(old_pol); 2286 } 2287 return 0; 2288 } 2289 2290 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2291 { 2292 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2293 struct net *net = xp_net(old); 2294 2295 if (newp) { 2296 newp->selector = old->selector; 2297 if (security_xfrm_policy_clone(old->security, 2298 &newp->security)) { 2299 kfree(newp); 2300 return NULL; /* ENOMEM */ 2301 } 2302 newp->lft = old->lft; 2303 newp->curlft = old->curlft; 2304 newp->mark = old->mark; 2305 newp->if_id = old->if_id; 2306 newp->action = old->action; 2307 newp->flags = old->flags; 2308 newp->xfrm_nr = old->xfrm_nr; 2309 newp->index = old->index; 2310 newp->type = old->type; 2311 newp->family = old->family; 2312 memcpy(newp->xfrm_vec, old->xfrm_vec, 2313 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2314 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2315 xfrm_sk_policy_link(newp, dir); 2316 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2317 xfrm_pol_put(newp); 2318 } 2319 return newp; 2320 } 2321 2322 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2323 { 2324 const struct xfrm_policy *p; 2325 struct xfrm_policy *np; 2326 int i, ret = 0; 2327 2328 rcu_read_lock(); 2329 for (i = 0; i < 2; i++) { 2330 p = rcu_dereference(osk->sk_policy[i]); 2331 if (p) { 2332 np = clone_policy(p, i); 2333 if (unlikely(!np)) { 2334 ret = -ENOMEM; 2335 break; 2336 } 2337 rcu_assign_pointer(sk->sk_policy[i], np); 2338 } 2339 } 2340 rcu_read_unlock(); 2341 return ret; 2342 } 2343 2344 static int 2345 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2346 xfrm_address_t *remote, unsigned short family, u32 mark) 2347 { 2348 int err; 2349 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2350 2351 if (unlikely(afinfo == NULL)) 2352 return -EINVAL; 2353 err = afinfo->get_saddr(net, oif, local, remote, mark); 2354 rcu_read_unlock(); 2355 return err; 2356 } 2357 2358 /* Resolve list of templates for the flow, given policy. */ 2359 2360 static int 2361 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2362 struct xfrm_state **xfrm, unsigned short family) 2363 { 2364 struct net *net = xp_net(policy); 2365 int nx; 2366 int i, error; 2367 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2368 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2369 xfrm_address_t tmp; 2370 2371 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2372 struct xfrm_state *x; 2373 xfrm_address_t *remote = daddr; 2374 xfrm_address_t *local = saddr; 2375 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2376 2377 if (tmpl->mode == XFRM_MODE_TUNNEL || 2378 tmpl->mode == XFRM_MODE_BEET) { 2379 remote = &tmpl->id.daddr; 2380 local = &tmpl->saddr; 2381 if (xfrm_addr_any(local, tmpl->encap_family)) { 2382 error = xfrm_get_saddr(net, fl->flowi_oif, 2383 &tmp, remote, 2384 tmpl->encap_family, 0); 2385 if (error) 2386 goto fail; 2387 local = &tmp; 2388 } 2389 } 2390 2391 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2392 family, policy->if_id); 2393 2394 if (x && x->km.state == XFRM_STATE_VALID) { 2395 xfrm[nx++] = x; 2396 daddr = remote; 2397 saddr = local; 2398 continue; 2399 } 2400 if (x) { 2401 error = (x->km.state == XFRM_STATE_ERROR ? 2402 -EINVAL : -EAGAIN); 2403 xfrm_state_put(x); 2404 } else if (error == -ESRCH) { 2405 error = -EAGAIN; 2406 } 2407 2408 if (!tmpl->optional) 2409 goto fail; 2410 } 2411 return nx; 2412 2413 fail: 2414 for (nx--; nx >= 0; nx--) 2415 xfrm_state_put(xfrm[nx]); 2416 return error; 2417 } 2418 2419 static int 2420 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2421 struct xfrm_state **xfrm, unsigned short family) 2422 { 2423 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2424 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2425 int cnx = 0; 2426 int error; 2427 int ret; 2428 int i; 2429 2430 for (i = 0; i < npols; i++) { 2431 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2432 error = -ENOBUFS; 2433 goto fail; 2434 } 2435 2436 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2437 if (ret < 0) { 2438 error = ret; 2439 goto fail; 2440 } else 2441 cnx += ret; 2442 } 2443 2444 /* found states are sorted for outbound processing */ 2445 if (npols > 1) 2446 xfrm_state_sort(xfrm, tpp, cnx, family); 2447 2448 return cnx; 2449 2450 fail: 2451 for (cnx--; cnx >= 0; cnx--) 2452 xfrm_state_put(tpp[cnx]); 2453 return error; 2454 2455 } 2456 2457 static int xfrm_get_tos(const struct flowi *fl, int family) 2458 { 2459 if (family == AF_INET) 2460 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2461 2462 return 0; 2463 } 2464 2465 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2466 { 2467 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2468 struct dst_ops *dst_ops; 2469 struct xfrm_dst *xdst; 2470 2471 if (!afinfo) 2472 return ERR_PTR(-EINVAL); 2473 2474 switch (family) { 2475 case AF_INET: 2476 dst_ops = &net->xfrm.xfrm4_dst_ops; 2477 break; 2478 #if IS_ENABLED(CONFIG_IPV6) 2479 case AF_INET6: 2480 dst_ops = &net->xfrm.xfrm6_dst_ops; 2481 break; 2482 #endif 2483 default: 2484 BUG(); 2485 } 2486 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2487 2488 if (likely(xdst)) { 2489 struct dst_entry *dst = &xdst->u.dst; 2490 2491 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 2492 } else 2493 xdst = ERR_PTR(-ENOBUFS); 2494 2495 rcu_read_unlock(); 2496 2497 return xdst; 2498 } 2499 2500 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2501 int nfheader_len) 2502 { 2503 if (dst->ops->family == AF_INET6) { 2504 struct rt6_info *rt = (struct rt6_info *)dst; 2505 path->path_cookie = rt6_get_cookie(rt); 2506 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2507 } 2508 } 2509 2510 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2511 const struct flowi *fl) 2512 { 2513 const struct xfrm_policy_afinfo *afinfo = 2514 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2515 int err; 2516 2517 if (!afinfo) 2518 return -EINVAL; 2519 2520 err = afinfo->fill_dst(xdst, dev, fl); 2521 2522 rcu_read_unlock(); 2523 2524 return err; 2525 } 2526 2527 2528 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2529 * all the metrics... Shortly, bundle a bundle. 2530 */ 2531 2532 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2533 struct xfrm_state **xfrm, 2534 struct xfrm_dst **bundle, 2535 int nx, 2536 const struct flowi *fl, 2537 struct dst_entry *dst) 2538 { 2539 const struct xfrm_state_afinfo *afinfo; 2540 const struct xfrm_mode *inner_mode; 2541 struct net *net = xp_net(policy); 2542 unsigned long now = jiffies; 2543 struct net_device *dev; 2544 struct xfrm_dst *xdst_prev = NULL; 2545 struct xfrm_dst *xdst0 = NULL; 2546 int i = 0; 2547 int err; 2548 int header_len = 0; 2549 int nfheader_len = 0; 2550 int trailer_len = 0; 2551 int tos; 2552 int family = policy->selector.family; 2553 xfrm_address_t saddr, daddr; 2554 2555 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2556 2557 tos = xfrm_get_tos(fl, family); 2558 2559 dst_hold(dst); 2560 2561 for (; i < nx; i++) { 2562 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2563 struct dst_entry *dst1 = &xdst->u.dst; 2564 2565 err = PTR_ERR(xdst); 2566 if (IS_ERR(xdst)) { 2567 dst_release(dst); 2568 goto put_states; 2569 } 2570 2571 bundle[i] = xdst; 2572 if (!xdst_prev) 2573 xdst0 = xdst; 2574 else 2575 /* Ref count is taken during xfrm_alloc_dst() 2576 * No need to do dst_clone() on dst1 2577 */ 2578 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2579 2580 if (xfrm[i]->sel.family == AF_UNSPEC) { 2581 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2582 xfrm_af2proto(family)); 2583 if (!inner_mode) { 2584 err = -EAFNOSUPPORT; 2585 dst_release(dst); 2586 goto put_states; 2587 } 2588 } else 2589 inner_mode = &xfrm[i]->inner_mode; 2590 2591 xdst->route = dst; 2592 dst_copy_metrics(dst1, dst); 2593 2594 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2595 __u32 mark = 0; 2596 2597 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2598 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2599 2600 family = xfrm[i]->props.family; 2601 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 2602 &saddr, &daddr, family, mark); 2603 err = PTR_ERR(dst); 2604 if (IS_ERR(dst)) 2605 goto put_states; 2606 } else 2607 dst_hold(dst); 2608 2609 dst1->xfrm = xfrm[i]; 2610 xdst->xfrm_genid = xfrm[i]->genid; 2611 2612 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2613 dst1->lastuse = now; 2614 2615 dst1->input = dst_discard; 2616 2617 rcu_read_lock(); 2618 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2619 if (likely(afinfo)) 2620 dst1->output = afinfo->output; 2621 else 2622 dst1->output = dst_discard_out; 2623 rcu_read_unlock(); 2624 2625 xdst_prev = xdst; 2626 2627 header_len += xfrm[i]->props.header_len; 2628 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2629 nfheader_len += xfrm[i]->props.header_len; 2630 trailer_len += xfrm[i]->props.trailer_len; 2631 } 2632 2633 xfrm_dst_set_child(xdst_prev, dst); 2634 xdst0->path = dst; 2635 2636 err = -ENODEV; 2637 dev = dst->dev; 2638 if (!dev) 2639 goto free_dst; 2640 2641 xfrm_init_path(xdst0, dst, nfheader_len); 2642 xfrm_init_pmtu(bundle, nx); 2643 2644 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2645 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2646 err = xfrm_fill_dst(xdst_prev, dev, fl); 2647 if (err) 2648 goto free_dst; 2649 2650 xdst_prev->u.dst.header_len = header_len; 2651 xdst_prev->u.dst.trailer_len = trailer_len; 2652 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2653 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2654 } 2655 2656 return &xdst0->u.dst; 2657 2658 put_states: 2659 for (; i < nx; i++) 2660 xfrm_state_put(xfrm[i]); 2661 free_dst: 2662 if (xdst0) 2663 dst_release_immediate(&xdst0->u.dst); 2664 2665 return ERR_PTR(err); 2666 } 2667 2668 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2669 struct xfrm_policy **pols, 2670 int *num_pols, int *num_xfrms) 2671 { 2672 int i; 2673 2674 if (*num_pols == 0 || !pols[0]) { 2675 *num_pols = 0; 2676 *num_xfrms = 0; 2677 return 0; 2678 } 2679 if (IS_ERR(pols[0])) 2680 return PTR_ERR(pols[0]); 2681 2682 *num_xfrms = pols[0]->xfrm_nr; 2683 2684 #ifdef CONFIG_XFRM_SUB_POLICY 2685 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 2686 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2687 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2688 XFRM_POLICY_TYPE_MAIN, 2689 fl, family, 2690 XFRM_POLICY_OUT, 2691 pols[0]->if_id); 2692 if (pols[1]) { 2693 if (IS_ERR(pols[1])) { 2694 xfrm_pols_put(pols, *num_pols); 2695 return PTR_ERR(pols[1]); 2696 } 2697 (*num_pols)++; 2698 (*num_xfrms) += pols[1]->xfrm_nr; 2699 } 2700 } 2701 #endif 2702 for (i = 0; i < *num_pols; i++) { 2703 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2704 *num_xfrms = -1; 2705 break; 2706 } 2707 } 2708 2709 return 0; 2710 2711 } 2712 2713 static struct xfrm_dst * 2714 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2715 const struct flowi *fl, u16 family, 2716 struct dst_entry *dst_orig) 2717 { 2718 struct net *net = xp_net(pols[0]); 2719 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2720 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2721 struct xfrm_dst *xdst; 2722 struct dst_entry *dst; 2723 int err; 2724 2725 /* Try to instantiate a bundle */ 2726 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2727 if (err <= 0) { 2728 if (err == 0) 2729 return NULL; 2730 2731 if (err != -EAGAIN) 2732 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2733 return ERR_PTR(err); 2734 } 2735 2736 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2737 if (IS_ERR(dst)) { 2738 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2739 return ERR_CAST(dst); 2740 } 2741 2742 xdst = (struct xfrm_dst *)dst; 2743 xdst->num_xfrms = err; 2744 xdst->num_pols = num_pols; 2745 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2746 xdst->policy_genid = atomic_read(&pols[0]->genid); 2747 2748 return xdst; 2749 } 2750 2751 static void xfrm_policy_queue_process(struct timer_list *t) 2752 { 2753 struct sk_buff *skb; 2754 struct sock *sk; 2755 struct dst_entry *dst; 2756 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2757 struct net *net = xp_net(pol); 2758 struct xfrm_policy_queue *pq = &pol->polq; 2759 struct flowi fl; 2760 struct sk_buff_head list; 2761 2762 spin_lock(&pq->hold_queue.lock); 2763 skb = skb_peek(&pq->hold_queue); 2764 if (!skb) { 2765 spin_unlock(&pq->hold_queue.lock); 2766 goto out; 2767 } 2768 dst = skb_dst(skb); 2769 sk = skb->sk; 2770 xfrm_decode_session(skb, &fl, dst->ops->family); 2771 spin_unlock(&pq->hold_queue.lock); 2772 2773 dst_hold(xfrm_dst_path(dst)); 2774 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2775 if (IS_ERR(dst)) 2776 goto purge_queue; 2777 2778 if (dst->flags & DST_XFRM_QUEUE) { 2779 dst_release(dst); 2780 2781 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2782 goto purge_queue; 2783 2784 pq->timeout = pq->timeout << 1; 2785 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2786 xfrm_pol_hold(pol); 2787 goto out; 2788 } 2789 2790 dst_release(dst); 2791 2792 __skb_queue_head_init(&list); 2793 2794 spin_lock(&pq->hold_queue.lock); 2795 pq->timeout = 0; 2796 skb_queue_splice_init(&pq->hold_queue, &list); 2797 spin_unlock(&pq->hold_queue.lock); 2798 2799 while (!skb_queue_empty(&list)) { 2800 skb = __skb_dequeue(&list); 2801 2802 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2803 dst_hold(xfrm_dst_path(skb_dst(skb))); 2804 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2805 if (IS_ERR(dst)) { 2806 kfree_skb(skb); 2807 continue; 2808 } 2809 2810 nf_reset_ct(skb); 2811 skb_dst_drop(skb); 2812 skb_dst_set(skb, dst); 2813 2814 dst_output(net, skb->sk, skb); 2815 } 2816 2817 out: 2818 xfrm_pol_put(pol); 2819 return; 2820 2821 purge_queue: 2822 pq->timeout = 0; 2823 skb_queue_purge(&pq->hold_queue); 2824 xfrm_pol_put(pol); 2825 } 2826 2827 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2828 { 2829 unsigned long sched_next; 2830 struct dst_entry *dst = skb_dst(skb); 2831 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2832 struct xfrm_policy *pol = xdst->pols[0]; 2833 struct xfrm_policy_queue *pq = &pol->polq; 2834 2835 if (unlikely(skb_fclone_busy(sk, skb))) { 2836 kfree_skb(skb); 2837 return 0; 2838 } 2839 2840 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2841 kfree_skb(skb); 2842 return -EAGAIN; 2843 } 2844 2845 skb_dst_force(skb); 2846 2847 spin_lock_bh(&pq->hold_queue.lock); 2848 2849 if (!pq->timeout) 2850 pq->timeout = XFRM_QUEUE_TMO_MIN; 2851 2852 sched_next = jiffies + pq->timeout; 2853 2854 if (del_timer(&pq->hold_timer)) { 2855 if (time_before(pq->hold_timer.expires, sched_next)) 2856 sched_next = pq->hold_timer.expires; 2857 xfrm_pol_put(pol); 2858 } 2859 2860 __skb_queue_tail(&pq->hold_queue, skb); 2861 if (!mod_timer(&pq->hold_timer, sched_next)) 2862 xfrm_pol_hold(pol); 2863 2864 spin_unlock_bh(&pq->hold_queue.lock); 2865 2866 return 0; 2867 } 2868 2869 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2870 struct xfrm_flo *xflo, 2871 const struct flowi *fl, 2872 int num_xfrms, 2873 u16 family) 2874 { 2875 int err; 2876 struct net_device *dev; 2877 struct dst_entry *dst; 2878 struct dst_entry *dst1; 2879 struct xfrm_dst *xdst; 2880 2881 xdst = xfrm_alloc_dst(net, family); 2882 if (IS_ERR(xdst)) 2883 return xdst; 2884 2885 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2886 net->xfrm.sysctl_larval_drop || 2887 num_xfrms <= 0) 2888 return xdst; 2889 2890 dst = xflo->dst_orig; 2891 dst1 = &xdst->u.dst; 2892 dst_hold(dst); 2893 xdst->route = dst; 2894 2895 dst_copy_metrics(dst1, dst); 2896 2897 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2898 dst1->flags |= DST_XFRM_QUEUE; 2899 dst1->lastuse = jiffies; 2900 2901 dst1->input = dst_discard; 2902 dst1->output = xdst_queue_output; 2903 2904 dst_hold(dst); 2905 xfrm_dst_set_child(xdst, dst); 2906 xdst->path = dst; 2907 2908 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2909 2910 err = -ENODEV; 2911 dev = dst->dev; 2912 if (!dev) 2913 goto free_dst; 2914 2915 err = xfrm_fill_dst(xdst, dev, fl); 2916 if (err) 2917 goto free_dst; 2918 2919 out: 2920 return xdst; 2921 2922 free_dst: 2923 dst_release(dst1); 2924 xdst = ERR_PTR(err); 2925 goto out; 2926 } 2927 2928 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2929 const struct flowi *fl, 2930 u16 family, u8 dir, 2931 struct xfrm_flo *xflo, u32 if_id) 2932 { 2933 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2934 int num_pols = 0, num_xfrms = 0, err; 2935 struct xfrm_dst *xdst; 2936 2937 /* Resolve policies to use if we couldn't get them from 2938 * previous cache entry */ 2939 num_pols = 1; 2940 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2941 err = xfrm_expand_policies(fl, family, pols, 2942 &num_pols, &num_xfrms); 2943 if (err < 0) 2944 goto inc_error; 2945 if (num_pols == 0) 2946 return NULL; 2947 if (num_xfrms <= 0) 2948 goto make_dummy_bundle; 2949 2950 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2951 xflo->dst_orig); 2952 if (IS_ERR(xdst)) { 2953 err = PTR_ERR(xdst); 2954 if (err == -EREMOTE) { 2955 xfrm_pols_put(pols, num_pols); 2956 return NULL; 2957 } 2958 2959 if (err != -EAGAIN) 2960 goto error; 2961 goto make_dummy_bundle; 2962 } else if (xdst == NULL) { 2963 num_xfrms = 0; 2964 goto make_dummy_bundle; 2965 } 2966 2967 return xdst; 2968 2969 make_dummy_bundle: 2970 /* We found policies, but there's no bundles to instantiate: 2971 * either because the policy blocks, has no transformations or 2972 * we could not build template (no xfrm_states).*/ 2973 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2974 if (IS_ERR(xdst)) { 2975 xfrm_pols_put(pols, num_pols); 2976 return ERR_CAST(xdst); 2977 } 2978 xdst->num_pols = num_pols; 2979 xdst->num_xfrms = num_xfrms; 2980 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2981 2982 return xdst; 2983 2984 inc_error: 2985 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2986 error: 2987 xfrm_pols_put(pols, num_pols); 2988 return ERR_PTR(err); 2989 } 2990 2991 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2992 struct dst_entry *dst_orig) 2993 { 2994 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2995 struct dst_entry *ret; 2996 2997 if (!afinfo) { 2998 dst_release(dst_orig); 2999 return ERR_PTR(-EINVAL); 3000 } else { 3001 ret = afinfo->blackhole_route(net, dst_orig); 3002 } 3003 rcu_read_unlock(); 3004 3005 return ret; 3006 } 3007 3008 /* Finds/creates a bundle for given flow and if_id 3009 * 3010 * At the moment we eat a raw IP route. Mostly to speed up lookups 3011 * on interfaces with disabled IPsec. 3012 * 3013 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3014 * compatibility 3015 */ 3016 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3017 struct dst_entry *dst_orig, 3018 const struct flowi *fl, 3019 const struct sock *sk, 3020 int flags, u32 if_id) 3021 { 3022 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3023 struct xfrm_dst *xdst; 3024 struct dst_entry *dst, *route; 3025 u16 family = dst_orig->ops->family; 3026 u8 dir = XFRM_POLICY_OUT; 3027 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3028 3029 dst = NULL; 3030 xdst = NULL; 3031 route = NULL; 3032 3033 sk = sk_const_to_full_sk(sk); 3034 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3035 num_pols = 1; 3036 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3037 if_id); 3038 err = xfrm_expand_policies(fl, family, pols, 3039 &num_pols, &num_xfrms); 3040 if (err < 0) 3041 goto dropdst; 3042 3043 if (num_pols) { 3044 if (num_xfrms <= 0) { 3045 drop_pols = num_pols; 3046 goto no_transform; 3047 } 3048 3049 xdst = xfrm_resolve_and_create_bundle( 3050 pols, num_pols, fl, 3051 family, dst_orig); 3052 3053 if (IS_ERR(xdst)) { 3054 xfrm_pols_put(pols, num_pols); 3055 err = PTR_ERR(xdst); 3056 if (err == -EREMOTE) 3057 goto nopol; 3058 3059 goto dropdst; 3060 } else if (xdst == NULL) { 3061 num_xfrms = 0; 3062 drop_pols = num_pols; 3063 goto no_transform; 3064 } 3065 3066 route = xdst->route; 3067 } 3068 } 3069 3070 if (xdst == NULL) { 3071 struct xfrm_flo xflo; 3072 3073 xflo.dst_orig = dst_orig; 3074 xflo.flags = flags; 3075 3076 /* To accelerate a bit... */ 3077 if ((dst_orig->flags & DST_NOXFRM) || 3078 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 3079 goto nopol; 3080 3081 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3082 if (xdst == NULL) 3083 goto nopol; 3084 if (IS_ERR(xdst)) { 3085 err = PTR_ERR(xdst); 3086 goto dropdst; 3087 } 3088 3089 num_pols = xdst->num_pols; 3090 num_xfrms = xdst->num_xfrms; 3091 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3092 route = xdst->route; 3093 } 3094 3095 dst = &xdst->u.dst; 3096 if (route == NULL && num_xfrms > 0) { 3097 /* The only case when xfrm_bundle_lookup() returns a 3098 * bundle with null route, is when the template could 3099 * not be resolved. It means policies are there, but 3100 * bundle could not be created, since we don't yet 3101 * have the xfrm_state's. We need to wait for KM to 3102 * negotiate new SA's or bail out with error.*/ 3103 if (net->xfrm.sysctl_larval_drop) { 3104 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3105 err = -EREMOTE; 3106 goto error; 3107 } 3108 3109 err = -EAGAIN; 3110 3111 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3112 goto error; 3113 } 3114 3115 no_transform: 3116 if (num_pols == 0) 3117 goto nopol; 3118 3119 if ((flags & XFRM_LOOKUP_ICMP) && 3120 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3121 err = -ENOENT; 3122 goto error; 3123 } 3124 3125 for (i = 0; i < num_pols; i++) 3126 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3127 3128 if (num_xfrms < 0) { 3129 /* Prohibit the flow */ 3130 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3131 err = -EPERM; 3132 goto error; 3133 } else if (num_xfrms > 0) { 3134 /* Flow transformed */ 3135 dst_release(dst_orig); 3136 } else { 3137 /* Flow passes untransformed */ 3138 dst_release(dst); 3139 dst = dst_orig; 3140 } 3141 ok: 3142 xfrm_pols_put(pols, drop_pols); 3143 if (dst && dst->xfrm && 3144 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3145 dst->flags |= DST_XFRM_TUNNEL; 3146 return dst; 3147 3148 nopol: 3149 if (!(flags & XFRM_LOOKUP_ICMP)) { 3150 dst = dst_orig; 3151 goto ok; 3152 } 3153 err = -ENOENT; 3154 error: 3155 dst_release(dst); 3156 dropdst: 3157 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3158 dst_release(dst_orig); 3159 xfrm_pols_put(pols, drop_pols); 3160 return ERR_PTR(err); 3161 } 3162 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3163 3164 /* Main function: finds/creates a bundle for given flow. 3165 * 3166 * At the moment we eat a raw IP route. Mostly to speed up lookups 3167 * on interfaces with disabled IPsec. 3168 */ 3169 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3170 const struct flowi *fl, const struct sock *sk, 3171 int flags) 3172 { 3173 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3174 } 3175 EXPORT_SYMBOL(xfrm_lookup); 3176 3177 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3178 * Otherwise we may send out blackholed packets. 3179 */ 3180 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3181 const struct flowi *fl, 3182 const struct sock *sk, int flags) 3183 { 3184 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3185 flags | XFRM_LOOKUP_QUEUE | 3186 XFRM_LOOKUP_KEEP_DST_REF); 3187 3188 if (PTR_ERR(dst) == -EREMOTE) 3189 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3190 3191 if (IS_ERR(dst)) 3192 dst_release(dst_orig); 3193 3194 return dst; 3195 } 3196 EXPORT_SYMBOL(xfrm_lookup_route); 3197 3198 static inline int 3199 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3200 { 3201 struct sec_path *sp = skb_sec_path(skb); 3202 struct xfrm_state *x; 3203 3204 if (!sp || idx < 0 || idx >= sp->len) 3205 return 0; 3206 x = sp->xvec[idx]; 3207 if (!x->type->reject) 3208 return 0; 3209 return x->type->reject(x, skb, fl); 3210 } 3211 3212 /* When skb is transformed back to its "native" form, we have to 3213 * check policy restrictions. At the moment we make this in maximally 3214 * stupid way. Shame on me. :-) Of course, connected sockets must 3215 * have policy cached at them. 3216 */ 3217 3218 static inline int 3219 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3220 unsigned short family) 3221 { 3222 if (xfrm_state_kern(x)) 3223 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3224 return x->id.proto == tmpl->id.proto && 3225 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3226 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3227 x->props.mode == tmpl->mode && 3228 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3229 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3230 !(x->props.mode != XFRM_MODE_TRANSPORT && 3231 xfrm_state_addr_cmp(tmpl, x, family)); 3232 } 3233 3234 /* 3235 * 0 or more than 0 is returned when validation is succeeded (either bypass 3236 * because of optional transport mode, or next index of the mathced secpath 3237 * state with the template. 3238 * -1 is returned when no matching template is found. 3239 * Otherwise "-2 - errored_index" is returned. 3240 */ 3241 static inline int 3242 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3243 unsigned short family) 3244 { 3245 int idx = start; 3246 3247 if (tmpl->optional) { 3248 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3249 return start; 3250 } else 3251 start = -1; 3252 for (; idx < sp->len; idx++) { 3253 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3254 return ++idx; 3255 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3256 if (start == -1) 3257 start = -2-idx; 3258 break; 3259 } 3260 } 3261 return start; 3262 } 3263 3264 static void 3265 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3266 { 3267 const struct iphdr *iph = ip_hdr(skb); 3268 int ihl = iph->ihl; 3269 u8 *xprth = skb_network_header(skb) + ihl * 4; 3270 struct flowi4 *fl4 = &fl->u.ip4; 3271 int oif = 0; 3272 3273 if (skb_dst(skb) && skb_dst(skb)->dev) 3274 oif = skb_dst(skb)->dev->ifindex; 3275 3276 memset(fl4, 0, sizeof(struct flowi4)); 3277 fl4->flowi4_mark = skb->mark; 3278 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3279 3280 fl4->flowi4_proto = iph->protocol; 3281 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3282 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3283 fl4->flowi4_tos = iph->tos; 3284 3285 if (!ip_is_fragment(iph)) { 3286 switch (iph->protocol) { 3287 case IPPROTO_UDP: 3288 case IPPROTO_UDPLITE: 3289 case IPPROTO_TCP: 3290 case IPPROTO_SCTP: 3291 case IPPROTO_DCCP: 3292 if (xprth + 4 < skb->data || 3293 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3294 __be16 *ports; 3295 3296 xprth = skb_network_header(skb) + ihl * 4; 3297 ports = (__be16 *)xprth; 3298 3299 fl4->fl4_sport = ports[!!reverse]; 3300 fl4->fl4_dport = ports[!reverse]; 3301 } 3302 break; 3303 case IPPROTO_ICMP: 3304 if (xprth + 2 < skb->data || 3305 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3306 u8 *icmp; 3307 3308 xprth = skb_network_header(skb) + ihl * 4; 3309 icmp = xprth; 3310 3311 fl4->fl4_icmp_type = icmp[0]; 3312 fl4->fl4_icmp_code = icmp[1]; 3313 } 3314 break; 3315 case IPPROTO_ESP: 3316 if (xprth + 4 < skb->data || 3317 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3318 __be32 *ehdr; 3319 3320 xprth = skb_network_header(skb) + ihl * 4; 3321 ehdr = (__be32 *)xprth; 3322 3323 fl4->fl4_ipsec_spi = ehdr[0]; 3324 } 3325 break; 3326 case IPPROTO_AH: 3327 if (xprth + 8 < skb->data || 3328 pskb_may_pull(skb, xprth + 8 - skb->data)) { 3329 __be32 *ah_hdr; 3330 3331 xprth = skb_network_header(skb) + ihl * 4; 3332 ah_hdr = (__be32 *)xprth; 3333 3334 fl4->fl4_ipsec_spi = ah_hdr[1]; 3335 } 3336 break; 3337 case IPPROTO_COMP: 3338 if (xprth + 4 < skb->data || 3339 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3340 __be16 *ipcomp_hdr; 3341 3342 xprth = skb_network_header(skb) + ihl * 4; 3343 ipcomp_hdr = (__be16 *)xprth; 3344 3345 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); 3346 } 3347 break; 3348 case IPPROTO_GRE: 3349 if (xprth + 12 < skb->data || 3350 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3351 __be16 *greflags; 3352 __be32 *gre_hdr; 3353 3354 xprth = skb_network_header(skb) + ihl * 4; 3355 greflags = (__be16 *)xprth; 3356 gre_hdr = (__be32 *)xprth; 3357 3358 if (greflags[0] & GRE_KEY) { 3359 if (greflags[0] & GRE_CSUM) 3360 gre_hdr++; 3361 fl4->fl4_gre_key = gre_hdr[1]; 3362 } 3363 } 3364 break; 3365 default: 3366 fl4->fl4_ipsec_spi = 0; 3367 break; 3368 } 3369 } 3370 } 3371 3372 #if IS_ENABLED(CONFIG_IPV6) 3373 static void 3374 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3375 { 3376 struct flowi6 *fl6 = &fl->u.ip6; 3377 int onlyproto = 0; 3378 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3379 u32 offset = sizeof(*hdr); 3380 struct ipv6_opt_hdr *exthdr; 3381 const unsigned char *nh = skb_network_header(skb); 3382 u16 nhoff = IP6CB(skb)->nhoff; 3383 int oif = 0; 3384 u8 nexthdr; 3385 3386 if (!nhoff) 3387 nhoff = offsetof(struct ipv6hdr, nexthdr); 3388 3389 nexthdr = nh[nhoff]; 3390 3391 if (skb_dst(skb) && skb_dst(skb)->dev) 3392 oif = skb_dst(skb)->dev->ifindex; 3393 3394 memset(fl6, 0, sizeof(struct flowi6)); 3395 fl6->flowi6_mark = skb->mark; 3396 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3397 3398 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3399 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3400 3401 while (nh + offset + sizeof(*exthdr) < skb->data || 3402 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3403 nh = skb_network_header(skb); 3404 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3405 3406 switch (nexthdr) { 3407 case NEXTHDR_FRAGMENT: 3408 onlyproto = 1; 3409 /* fall through */ 3410 case NEXTHDR_ROUTING: 3411 case NEXTHDR_HOP: 3412 case NEXTHDR_DEST: 3413 offset += ipv6_optlen(exthdr); 3414 nexthdr = exthdr->nexthdr; 3415 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3416 break; 3417 case IPPROTO_UDP: 3418 case IPPROTO_UDPLITE: 3419 case IPPROTO_TCP: 3420 case IPPROTO_SCTP: 3421 case IPPROTO_DCCP: 3422 if (!onlyproto && (nh + offset + 4 < skb->data || 3423 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3424 __be16 *ports; 3425 3426 nh = skb_network_header(skb); 3427 ports = (__be16 *)(nh + offset); 3428 fl6->fl6_sport = ports[!!reverse]; 3429 fl6->fl6_dport = ports[!reverse]; 3430 } 3431 fl6->flowi6_proto = nexthdr; 3432 return; 3433 case IPPROTO_ICMPV6: 3434 if (!onlyproto && (nh + offset + 2 < skb->data || 3435 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3436 u8 *icmp; 3437 3438 nh = skb_network_header(skb); 3439 icmp = (u8 *)(nh + offset); 3440 fl6->fl6_icmp_type = icmp[0]; 3441 fl6->fl6_icmp_code = icmp[1]; 3442 } 3443 fl6->flowi6_proto = nexthdr; 3444 return; 3445 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3446 case IPPROTO_MH: 3447 offset += ipv6_optlen(exthdr); 3448 if (!onlyproto && (nh + offset + 3 < skb->data || 3449 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3450 struct ip6_mh *mh; 3451 3452 nh = skb_network_header(skb); 3453 mh = (struct ip6_mh *)(nh + offset); 3454 fl6->fl6_mh_type = mh->ip6mh_type; 3455 } 3456 fl6->flowi6_proto = nexthdr; 3457 return; 3458 #endif 3459 /* XXX Why are there these headers? */ 3460 case IPPROTO_AH: 3461 case IPPROTO_ESP: 3462 case IPPROTO_COMP: 3463 default: 3464 fl6->fl6_ipsec_spi = 0; 3465 fl6->flowi6_proto = nexthdr; 3466 return; 3467 } 3468 } 3469 } 3470 #endif 3471 3472 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3473 unsigned int family, int reverse) 3474 { 3475 switch (family) { 3476 case AF_INET: 3477 decode_session4(skb, fl, reverse); 3478 break; 3479 #if IS_ENABLED(CONFIG_IPV6) 3480 case AF_INET6: 3481 decode_session6(skb, fl, reverse); 3482 break; 3483 #endif 3484 default: 3485 return -EAFNOSUPPORT; 3486 } 3487 3488 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3489 } 3490 EXPORT_SYMBOL(__xfrm_decode_session); 3491 3492 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3493 { 3494 for (; k < sp->len; k++) { 3495 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3496 *idxp = k; 3497 return 1; 3498 } 3499 } 3500 3501 return 0; 3502 } 3503 3504 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3505 unsigned short family) 3506 { 3507 struct net *net = dev_net(skb->dev); 3508 struct xfrm_policy *pol; 3509 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3510 int npols = 0; 3511 int xfrm_nr; 3512 int pi; 3513 int reverse; 3514 struct flowi fl; 3515 int xerr_idx = -1; 3516 const struct xfrm_if_cb *ifcb; 3517 struct sec_path *sp; 3518 struct xfrm_if *xi; 3519 u32 if_id = 0; 3520 3521 rcu_read_lock(); 3522 ifcb = xfrm_if_get_cb(); 3523 3524 if (ifcb) { 3525 xi = ifcb->decode_session(skb, family); 3526 if (xi) { 3527 if_id = xi->p.if_id; 3528 net = xi->net; 3529 } 3530 } 3531 rcu_read_unlock(); 3532 3533 reverse = dir & ~XFRM_POLICY_MASK; 3534 dir &= XFRM_POLICY_MASK; 3535 3536 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3537 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3538 return 0; 3539 } 3540 3541 nf_nat_decode_session(skb, &fl, family); 3542 3543 /* First, check used SA against their selectors. */ 3544 sp = skb_sec_path(skb); 3545 if (sp) { 3546 int i; 3547 3548 for (i = sp->len - 1; i >= 0; i--) { 3549 struct xfrm_state *x = sp->xvec[i]; 3550 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3551 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3552 return 0; 3553 } 3554 } 3555 } 3556 3557 pol = NULL; 3558 sk = sk_to_full_sk(sk); 3559 if (sk && sk->sk_policy[dir]) { 3560 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3561 if (IS_ERR(pol)) { 3562 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3563 return 0; 3564 } 3565 } 3566 3567 if (!pol) 3568 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3569 3570 if (IS_ERR(pol)) { 3571 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3572 return 0; 3573 } 3574 3575 if (!pol) { 3576 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3577 xfrm_secpath_reject(xerr_idx, skb, &fl); 3578 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3579 return 0; 3580 } 3581 return 1; 3582 } 3583 3584 pol->curlft.use_time = ktime_get_real_seconds(); 3585 3586 pols[0] = pol; 3587 npols++; 3588 #ifdef CONFIG_XFRM_SUB_POLICY 3589 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3590 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3591 &fl, family, 3592 XFRM_POLICY_IN, if_id); 3593 if (pols[1]) { 3594 if (IS_ERR(pols[1])) { 3595 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3596 return 0; 3597 } 3598 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3599 npols++; 3600 } 3601 } 3602 #endif 3603 3604 if (pol->action == XFRM_POLICY_ALLOW) { 3605 static struct sec_path dummy; 3606 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3607 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3608 struct xfrm_tmpl **tpp = tp; 3609 int ti = 0; 3610 int i, k; 3611 3612 sp = skb_sec_path(skb); 3613 if (!sp) 3614 sp = &dummy; 3615 3616 for (pi = 0; pi < npols; pi++) { 3617 if (pols[pi] != pol && 3618 pols[pi]->action != XFRM_POLICY_ALLOW) { 3619 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3620 goto reject; 3621 } 3622 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3623 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3624 goto reject_error; 3625 } 3626 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3627 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3628 } 3629 xfrm_nr = ti; 3630 if (npols > 1) { 3631 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3632 tpp = stp; 3633 } 3634 3635 /* For each tunnel xfrm, find the first matching tmpl. 3636 * For each tmpl before that, find corresponding xfrm. 3637 * Order is _important_. Later we will implement 3638 * some barriers, but at the moment barriers 3639 * are implied between each two transformations. 3640 */ 3641 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3642 k = xfrm_policy_ok(tpp[i], sp, k, family); 3643 if (k < 0) { 3644 if (k < -1) 3645 /* "-2 - errored_index" returned */ 3646 xerr_idx = -(2+k); 3647 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3648 goto reject; 3649 } 3650 } 3651 3652 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3653 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3654 goto reject; 3655 } 3656 3657 xfrm_pols_put(pols, npols); 3658 return 1; 3659 } 3660 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3661 3662 reject: 3663 xfrm_secpath_reject(xerr_idx, skb, &fl); 3664 reject_error: 3665 xfrm_pols_put(pols, npols); 3666 return 0; 3667 } 3668 EXPORT_SYMBOL(__xfrm_policy_check); 3669 3670 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3671 { 3672 struct net *net = dev_net(skb->dev); 3673 struct flowi fl; 3674 struct dst_entry *dst; 3675 int res = 1; 3676 3677 if (xfrm_decode_session(skb, &fl, family) < 0) { 3678 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3679 return 0; 3680 } 3681 3682 skb_dst_force(skb); 3683 if (!skb_dst(skb)) { 3684 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3685 return 0; 3686 } 3687 3688 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3689 if (IS_ERR(dst)) { 3690 res = 0; 3691 dst = NULL; 3692 } 3693 skb_dst_set(skb, dst); 3694 return res; 3695 } 3696 EXPORT_SYMBOL(__xfrm_route_forward); 3697 3698 /* Optimize later using cookies and generation ids. */ 3699 3700 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3701 { 3702 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3703 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3704 * get validated by dst_ops->check on every use. We do this 3705 * because when a normal route referenced by an XFRM dst is 3706 * obsoleted we do not go looking around for all parent 3707 * referencing XFRM dsts so that we can invalidate them. It 3708 * is just too much work. Instead we make the checks here on 3709 * every use. For example: 3710 * 3711 * XFRM dst A --> IPv4 dst X 3712 * 3713 * X is the "xdst->route" of A (X is also the "dst->path" of A 3714 * in this example). If X is marked obsolete, "A" will not 3715 * notice. That's what we are validating here via the 3716 * stale_bundle() check. 3717 * 3718 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3719 * be marked on it. 3720 * This will force stale_bundle() to fail on any xdst bundle with 3721 * this dst linked in it. 3722 */ 3723 if (dst->obsolete < 0 && !stale_bundle(dst)) 3724 return dst; 3725 3726 return NULL; 3727 } 3728 3729 static int stale_bundle(struct dst_entry *dst) 3730 { 3731 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3732 } 3733 3734 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3735 { 3736 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3737 dst->dev = dev_net(dev)->loopback_dev; 3738 dev_hold(dst->dev); 3739 dev_put(dev); 3740 } 3741 } 3742 EXPORT_SYMBOL(xfrm_dst_ifdown); 3743 3744 static void xfrm_link_failure(struct sk_buff *skb) 3745 { 3746 /* Impossible. Such dst must be popped before reaches point of failure. */ 3747 } 3748 3749 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3750 { 3751 if (dst) { 3752 if (dst->obsolete) { 3753 dst_release(dst); 3754 dst = NULL; 3755 } 3756 } 3757 return dst; 3758 } 3759 3760 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3761 { 3762 while (nr--) { 3763 struct xfrm_dst *xdst = bundle[nr]; 3764 u32 pmtu, route_mtu_cached; 3765 struct dst_entry *dst; 3766 3767 dst = &xdst->u.dst; 3768 pmtu = dst_mtu(xfrm_dst_child(dst)); 3769 xdst->child_mtu_cached = pmtu; 3770 3771 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3772 3773 route_mtu_cached = dst_mtu(xdst->route); 3774 xdst->route_mtu_cached = route_mtu_cached; 3775 3776 if (pmtu > route_mtu_cached) 3777 pmtu = route_mtu_cached; 3778 3779 dst_metric_set(dst, RTAX_MTU, pmtu); 3780 } 3781 } 3782 3783 /* Check that the bundle accepts the flow and its components are 3784 * still valid. 3785 */ 3786 3787 static int xfrm_bundle_ok(struct xfrm_dst *first) 3788 { 3789 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3790 struct dst_entry *dst = &first->u.dst; 3791 struct xfrm_dst *xdst; 3792 int start_from, nr; 3793 u32 mtu; 3794 3795 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3796 (dst->dev && !netif_running(dst->dev))) 3797 return 0; 3798 3799 if (dst->flags & DST_XFRM_QUEUE) 3800 return 1; 3801 3802 start_from = nr = 0; 3803 do { 3804 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3805 3806 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3807 return 0; 3808 if (xdst->xfrm_genid != dst->xfrm->genid) 3809 return 0; 3810 if (xdst->num_pols > 0 && 3811 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3812 return 0; 3813 3814 bundle[nr++] = xdst; 3815 3816 mtu = dst_mtu(xfrm_dst_child(dst)); 3817 if (xdst->child_mtu_cached != mtu) { 3818 start_from = nr; 3819 xdst->child_mtu_cached = mtu; 3820 } 3821 3822 if (!dst_check(xdst->route, xdst->route_cookie)) 3823 return 0; 3824 mtu = dst_mtu(xdst->route); 3825 if (xdst->route_mtu_cached != mtu) { 3826 start_from = nr; 3827 xdst->route_mtu_cached = mtu; 3828 } 3829 3830 dst = xfrm_dst_child(dst); 3831 } while (dst->xfrm); 3832 3833 if (likely(!start_from)) 3834 return 1; 3835 3836 xdst = bundle[start_from - 1]; 3837 mtu = xdst->child_mtu_cached; 3838 while (start_from--) { 3839 dst = &xdst->u.dst; 3840 3841 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3842 if (mtu > xdst->route_mtu_cached) 3843 mtu = xdst->route_mtu_cached; 3844 dst_metric_set(dst, RTAX_MTU, mtu); 3845 if (!start_from) 3846 break; 3847 3848 xdst = bundle[start_from - 1]; 3849 xdst->child_mtu_cached = mtu; 3850 } 3851 3852 return 1; 3853 } 3854 3855 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3856 { 3857 return dst_metric_advmss(xfrm_dst_path(dst)); 3858 } 3859 3860 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3861 { 3862 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3863 3864 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3865 } 3866 3867 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3868 const void *daddr) 3869 { 3870 while (dst->xfrm) { 3871 const struct xfrm_state *xfrm = dst->xfrm; 3872 3873 dst = xfrm_dst_child(dst); 3874 3875 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3876 continue; 3877 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3878 daddr = xfrm->coaddr; 3879 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3880 daddr = &xfrm->id.daddr; 3881 } 3882 return daddr; 3883 } 3884 3885 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3886 struct sk_buff *skb, 3887 const void *daddr) 3888 { 3889 const struct dst_entry *path = xfrm_dst_path(dst); 3890 3891 if (!skb) 3892 daddr = xfrm_get_dst_nexthop(dst, daddr); 3893 return path->ops->neigh_lookup(path, skb, daddr); 3894 } 3895 3896 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3897 { 3898 const struct dst_entry *path = xfrm_dst_path(dst); 3899 3900 daddr = xfrm_get_dst_nexthop(dst, daddr); 3901 path->ops->confirm_neigh(path, daddr); 3902 } 3903 3904 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3905 { 3906 int err = 0; 3907 3908 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3909 return -EAFNOSUPPORT; 3910 3911 spin_lock(&xfrm_policy_afinfo_lock); 3912 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3913 err = -EEXIST; 3914 else { 3915 struct dst_ops *dst_ops = afinfo->dst_ops; 3916 if (likely(dst_ops->kmem_cachep == NULL)) 3917 dst_ops->kmem_cachep = xfrm_dst_cache; 3918 if (likely(dst_ops->check == NULL)) 3919 dst_ops->check = xfrm_dst_check; 3920 if (likely(dst_ops->default_advmss == NULL)) 3921 dst_ops->default_advmss = xfrm_default_advmss; 3922 if (likely(dst_ops->mtu == NULL)) 3923 dst_ops->mtu = xfrm_mtu; 3924 if (likely(dst_ops->negative_advice == NULL)) 3925 dst_ops->negative_advice = xfrm_negative_advice; 3926 if (likely(dst_ops->link_failure == NULL)) 3927 dst_ops->link_failure = xfrm_link_failure; 3928 if (likely(dst_ops->neigh_lookup == NULL)) 3929 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3930 if (likely(!dst_ops->confirm_neigh)) 3931 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3932 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3933 } 3934 spin_unlock(&xfrm_policy_afinfo_lock); 3935 3936 return err; 3937 } 3938 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3939 3940 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3941 { 3942 struct dst_ops *dst_ops = afinfo->dst_ops; 3943 int i; 3944 3945 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3946 if (xfrm_policy_afinfo[i] != afinfo) 3947 continue; 3948 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3949 break; 3950 } 3951 3952 synchronize_rcu(); 3953 3954 dst_ops->kmem_cachep = NULL; 3955 dst_ops->check = NULL; 3956 dst_ops->negative_advice = NULL; 3957 dst_ops->link_failure = NULL; 3958 } 3959 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3960 3961 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3962 { 3963 spin_lock(&xfrm_if_cb_lock); 3964 rcu_assign_pointer(xfrm_if_cb, ifcb); 3965 spin_unlock(&xfrm_if_cb_lock); 3966 } 3967 EXPORT_SYMBOL(xfrm_if_register_cb); 3968 3969 void xfrm_if_unregister_cb(void) 3970 { 3971 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3972 synchronize_rcu(); 3973 } 3974 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3975 3976 #ifdef CONFIG_XFRM_STATISTICS 3977 static int __net_init xfrm_statistics_init(struct net *net) 3978 { 3979 int rv; 3980 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3981 if (!net->mib.xfrm_statistics) 3982 return -ENOMEM; 3983 rv = xfrm_proc_init(net); 3984 if (rv < 0) 3985 free_percpu(net->mib.xfrm_statistics); 3986 return rv; 3987 } 3988 3989 static void xfrm_statistics_fini(struct net *net) 3990 { 3991 xfrm_proc_fini(net); 3992 free_percpu(net->mib.xfrm_statistics); 3993 } 3994 #else 3995 static int __net_init xfrm_statistics_init(struct net *net) 3996 { 3997 return 0; 3998 } 3999 4000 static void xfrm_statistics_fini(struct net *net) 4001 { 4002 } 4003 #endif 4004 4005 static int __net_init xfrm_policy_init(struct net *net) 4006 { 4007 unsigned int hmask, sz; 4008 int dir, err; 4009 4010 if (net_eq(net, &init_net)) { 4011 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4012 sizeof(struct xfrm_dst), 4013 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4014 NULL); 4015 err = rhashtable_init(&xfrm_policy_inexact_table, 4016 &xfrm_pol_inexact_params); 4017 BUG_ON(err); 4018 } 4019 4020 hmask = 8 - 1; 4021 sz = (hmask+1) * sizeof(struct hlist_head); 4022 4023 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4024 if (!net->xfrm.policy_byidx) 4025 goto out_byidx; 4026 net->xfrm.policy_idx_hmask = hmask; 4027 4028 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4029 struct xfrm_policy_hash *htab; 4030 4031 net->xfrm.policy_count[dir] = 0; 4032 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4033 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4034 4035 htab = &net->xfrm.policy_bydst[dir]; 4036 htab->table = xfrm_hash_alloc(sz); 4037 if (!htab->table) 4038 goto out_bydst; 4039 htab->hmask = hmask; 4040 htab->dbits4 = 32; 4041 htab->sbits4 = 32; 4042 htab->dbits6 = 128; 4043 htab->sbits6 = 128; 4044 } 4045 net->xfrm.policy_hthresh.lbits4 = 32; 4046 net->xfrm.policy_hthresh.rbits4 = 32; 4047 net->xfrm.policy_hthresh.lbits6 = 128; 4048 net->xfrm.policy_hthresh.rbits6 = 128; 4049 4050 seqlock_init(&net->xfrm.policy_hthresh.lock); 4051 4052 INIT_LIST_HEAD(&net->xfrm.policy_all); 4053 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4054 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4055 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4056 return 0; 4057 4058 out_bydst: 4059 for (dir--; dir >= 0; dir--) { 4060 struct xfrm_policy_hash *htab; 4061 4062 htab = &net->xfrm.policy_bydst[dir]; 4063 xfrm_hash_free(htab->table, sz); 4064 } 4065 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4066 out_byidx: 4067 return -ENOMEM; 4068 } 4069 4070 static void xfrm_policy_fini(struct net *net) 4071 { 4072 struct xfrm_pol_inexact_bin *b, *t; 4073 unsigned int sz; 4074 int dir; 4075 4076 flush_work(&net->xfrm.policy_hash_work); 4077 #ifdef CONFIG_XFRM_SUB_POLICY 4078 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4079 #endif 4080 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4081 4082 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4083 4084 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4085 struct xfrm_policy_hash *htab; 4086 4087 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4088 4089 htab = &net->xfrm.policy_bydst[dir]; 4090 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4091 WARN_ON(!hlist_empty(htab->table)); 4092 xfrm_hash_free(htab->table, sz); 4093 } 4094 4095 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4096 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4097 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4098 4099 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4100 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4101 __xfrm_policy_inexact_prune_bin(b, true); 4102 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4103 } 4104 4105 static int __net_init xfrm_net_init(struct net *net) 4106 { 4107 int rv; 4108 4109 /* Initialize the per-net locks here */ 4110 spin_lock_init(&net->xfrm.xfrm_state_lock); 4111 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4112 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4113 4114 rv = xfrm_statistics_init(net); 4115 if (rv < 0) 4116 goto out_statistics; 4117 rv = xfrm_state_init(net); 4118 if (rv < 0) 4119 goto out_state; 4120 rv = xfrm_policy_init(net); 4121 if (rv < 0) 4122 goto out_policy; 4123 rv = xfrm_sysctl_init(net); 4124 if (rv < 0) 4125 goto out_sysctl; 4126 4127 return 0; 4128 4129 out_sysctl: 4130 xfrm_policy_fini(net); 4131 out_policy: 4132 xfrm_state_fini(net); 4133 out_state: 4134 xfrm_statistics_fini(net); 4135 out_statistics: 4136 return rv; 4137 } 4138 4139 static void __net_exit xfrm_net_exit(struct net *net) 4140 { 4141 xfrm_sysctl_fini(net); 4142 xfrm_policy_fini(net); 4143 xfrm_state_fini(net); 4144 xfrm_statistics_fini(net); 4145 } 4146 4147 static struct pernet_operations __net_initdata xfrm_net_ops = { 4148 .init = xfrm_net_init, 4149 .exit = xfrm_net_exit, 4150 }; 4151 4152 void __init xfrm_init(void) 4153 { 4154 register_pernet_subsys(&xfrm_net_ops); 4155 xfrm_dev_init(); 4156 seqcount_init(&xfrm_policy_hash_generation); 4157 xfrm_input_init(); 4158 4159 #ifdef CONFIG_INET_ESPINTCP 4160 espintcp_init(); 4161 #endif 4162 4163 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4164 synchronize_rcu(); 4165 } 4166 4167 #ifdef CONFIG_AUDITSYSCALL 4168 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4169 struct audit_buffer *audit_buf) 4170 { 4171 struct xfrm_sec_ctx *ctx = xp->security; 4172 struct xfrm_selector *sel = &xp->selector; 4173 4174 if (ctx) 4175 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4176 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4177 4178 switch (sel->family) { 4179 case AF_INET: 4180 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4181 if (sel->prefixlen_s != 32) 4182 audit_log_format(audit_buf, " src_prefixlen=%d", 4183 sel->prefixlen_s); 4184 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4185 if (sel->prefixlen_d != 32) 4186 audit_log_format(audit_buf, " dst_prefixlen=%d", 4187 sel->prefixlen_d); 4188 break; 4189 case AF_INET6: 4190 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4191 if (sel->prefixlen_s != 128) 4192 audit_log_format(audit_buf, " src_prefixlen=%d", 4193 sel->prefixlen_s); 4194 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4195 if (sel->prefixlen_d != 128) 4196 audit_log_format(audit_buf, " dst_prefixlen=%d", 4197 sel->prefixlen_d); 4198 break; 4199 } 4200 } 4201 4202 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4203 { 4204 struct audit_buffer *audit_buf; 4205 4206 audit_buf = xfrm_audit_start("SPD-add"); 4207 if (audit_buf == NULL) 4208 return; 4209 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4210 audit_log_format(audit_buf, " res=%u", result); 4211 xfrm_audit_common_policyinfo(xp, audit_buf); 4212 audit_log_end(audit_buf); 4213 } 4214 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4215 4216 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4217 bool task_valid) 4218 { 4219 struct audit_buffer *audit_buf; 4220 4221 audit_buf = xfrm_audit_start("SPD-delete"); 4222 if (audit_buf == NULL) 4223 return; 4224 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4225 audit_log_format(audit_buf, " res=%u", result); 4226 xfrm_audit_common_policyinfo(xp, audit_buf); 4227 audit_log_end(audit_buf); 4228 } 4229 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4230 #endif 4231 4232 #ifdef CONFIG_XFRM_MIGRATE 4233 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4234 const struct xfrm_selector *sel_tgt) 4235 { 4236 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4237 if (sel_tgt->family == sel_cmp->family && 4238 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4239 sel_cmp->family) && 4240 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4241 sel_cmp->family) && 4242 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4243 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4244 return true; 4245 } 4246 } else { 4247 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4248 return true; 4249 } 4250 } 4251 return false; 4252 } 4253 4254 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4255 u8 dir, u8 type, struct net *net) 4256 { 4257 struct xfrm_policy *pol, *ret = NULL; 4258 struct hlist_head *chain; 4259 u32 priority = ~0U; 4260 4261 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4262 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4263 hlist_for_each_entry(pol, chain, bydst) { 4264 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4265 pol->type == type) { 4266 ret = pol; 4267 priority = ret->priority; 4268 break; 4269 } 4270 } 4271 chain = &net->xfrm.policy_inexact[dir]; 4272 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4273 if ((pol->priority >= priority) && ret) 4274 break; 4275 4276 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4277 pol->type == type) { 4278 ret = pol; 4279 break; 4280 } 4281 } 4282 4283 xfrm_pol_hold(ret); 4284 4285 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4286 4287 return ret; 4288 } 4289 4290 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4291 { 4292 int match = 0; 4293 4294 if (t->mode == m->mode && t->id.proto == m->proto && 4295 (m->reqid == 0 || t->reqid == m->reqid)) { 4296 switch (t->mode) { 4297 case XFRM_MODE_TUNNEL: 4298 case XFRM_MODE_BEET: 4299 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4300 m->old_family) && 4301 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4302 m->old_family)) { 4303 match = 1; 4304 } 4305 break; 4306 case XFRM_MODE_TRANSPORT: 4307 /* in case of transport mode, template does not store 4308 any IP addresses, hence we just compare mode and 4309 protocol */ 4310 match = 1; 4311 break; 4312 default: 4313 break; 4314 } 4315 } 4316 return match; 4317 } 4318 4319 /* update endpoint address(es) of template(s) */ 4320 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4321 struct xfrm_migrate *m, int num_migrate) 4322 { 4323 struct xfrm_migrate *mp; 4324 int i, j, n = 0; 4325 4326 write_lock_bh(&pol->lock); 4327 if (unlikely(pol->walk.dead)) { 4328 /* target policy has been deleted */ 4329 write_unlock_bh(&pol->lock); 4330 return -ENOENT; 4331 } 4332 4333 for (i = 0; i < pol->xfrm_nr; i++) { 4334 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4335 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4336 continue; 4337 n++; 4338 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4339 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4340 continue; 4341 /* update endpoints */ 4342 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4343 sizeof(pol->xfrm_vec[i].id.daddr)); 4344 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4345 sizeof(pol->xfrm_vec[i].saddr)); 4346 pol->xfrm_vec[i].encap_family = mp->new_family; 4347 /* flush bundles */ 4348 atomic_inc(&pol->genid); 4349 } 4350 } 4351 4352 write_unlock_bh(&pol->lock); 4353 4354 if (!n) 4355 return -ENODATA; 4356 4357 return 0; 4358 } 4359 4360 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4361 { 4362 int i, j; 4363 4364 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4365 return -EINVAL; 4366 4367 for (i = 0; i < num_migrate; i++) { 4368 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4369 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4370 return -EINVAL; 4371 4372 /* check if there is any duplicated entry */ 4373 for (j = i + 1; j < num_migrate; j++) { 4374 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4375 sizeof(m[i].old_daddr)) && 4376 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4377 sizeof(m[i].old_saddr)) && 4378 m[i].proto == m[j].proto && 4379 m[i].mode == m[j].mode && 4380 m[i].reqid == m[j].reqid && 4381 m[i].old_family == m[j].old_family) 4382 return -EINVAL; 4383 } 4384 } 4385 4386 return 0; 4387 } 4388 4389 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4390 struct xfrm_migrate *m, int num_migrate, 4391 struct xfrm_kmaddress *k, struct net *net, 4392 struct xfrm_encap_tmpl *encap) 4393 { 4394 int i, err, nx_cur = 0, nx_new = 0; 4395 struct xfrm_policy *pol = NULL; 4396 struct xfrm_state *x, *xc; 4397 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4398 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4399 struct xfrm_migrate *mp; 4400 4401 /* Stage 0 - sanity checks */ 4402 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4403 goto out; 4404 4405 if (dir >= XFRM_POLICY_MAX) { 4406 err = -EINVAL; 4407 goto out; 4408 } 4409 4410 /* Stage 1 - find policy */ 4411 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4412 err = -ENOENT; 4413 goto out; 4414 } 4415 4416 /* Stage 2 - find and update state(s) */ 4417 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4418 if ((x = xfrm_migrate_state_find(mp, net))) { 4419 x_cur[nx_cur] = x; 4420 nx_cur++; 4421 xc = xfrm_state_migrate(x, mp, encap); 4422 if (xc) { 4423 x_new[nx_new] = xc; 4424 nx_new++; 4425 } else { 4426 err = -ENODATA; 4427 goto restore_state; 4428 } 4429 } 4430 } 4431 4432 /* Stage 3 - update policy */ 4433 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4434 goto restore_state; 4435 4436 /* Stage 4 - delete old state(s) */ 4437 if (nx_cur) { 4438 xfrm_states_put(x_cur, nx_cur); 4439 xfrm_states_delete(x_cur, nx_cur); 4440 } 4441 4442 /* Stage 5 - announce */ 4443 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4444 4445 xfrm_pol_put(pol); 4446 4447 return 0; 4448 out: 4449 return err; 4450 4451 restore_state: 4452 if (pol) 4453 xfrm_pol_put(pol); 4454 if (nx_cur) 4455 xfrm_states_put(x_cur, nx_cur); 4456 if (nx_new) 4457 xfrm_states_delete(x_new, nx_new); 4458 4459 return err; 4460 } 4461 EXPORT_SYMBOL(xfrm_migrate); 4462 #endif 4463