1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * xfrm_policy.c 4 * 5 * Changes: 6 * Mitsuru KANDA @USAGI 7 * Kazunori MIYAZAWA @USAGI 8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 9 * IPv6 support 10 * Kazunori MIYAZAWA @USAGI 11 * YOSHIFUJI Hideaki 12 * Split up af-specific portion 13 * Derek Atkins <derek@ihtfp.com> Add the post_input processor 14 * 15 */ 16 17 #include <linux/err.h> 18 #include <linux/slab.h> 19 #include <linux/kmod.h> 20 #include <linux/list.h> 21 #include <linux/spinlock.h> 22 #include <linux/workqueue.h> 23 #include <linux/notifier.h> 24 #include <linux/netdevice.h> 25 #include <linux/netfilter.h> 26 #include <linux/module.h> 27 #include <linux/cache.h> 28 #include <linux/cpu.h> 29 #include <linux/audit.h> 30 #include <linux/rhashtable.h> 31 #include <linux/if_tunnel.h> 32 #include <net/dst.h> 33 #include <net/flow.h> 34 #include <net/xfrm.h> 35 #include <net/ip.h> 36 #if IS_ENABLED(CONFIG_IPV6_MIP6) 37 #include <net/mip6.h> 38 #endif 39 #ifdef CONFIG_XFRM_STATISTICS 40 #include <net/snmp.h> 41 #endif 42 #ifdef CONFIG_XFRM_ESPINTCP 43 #include <net/espintcp.h> 44 #endif 45 46 #include "xfrm_hash.h" 47 48 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 49 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 50 #define XFRM_MAX_QUEUE_LEN 100 51 52 struct xfrm_flo { 53 struct dst_entry *dst_orig; 54 u8 flags; 55 }; 56 57 /* prefixes smaller than this are stored in lists, not trees. */ 58 #define INEXACT_PREFIXLEN_IPV4 16 59 #define INEXACT_PREFIXLEN_IPV6 48 60 61 struct xfrm_pol_inexact_node { 62 struct rb_node node; 63 union { 64 xfrm_address_t addr; 65 struct rcu_head rcu; 66 }; 67 u8 prefixlen; 68 69 struct rb_root root; 70 71 /* the policies matching this node, can be empty list */ 72 struct hlist_head hhead; 73 }; 74 75 /* xfrm inexact policy search tree: 76 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id); 77 * | 78 * +---- root_d: sorted by daddr:prefix 79 * | | 80 * | xfrm_pol_inexact_node 81 * | | 82 * | +- root: sorted by saddr/prefix 83 * | | | 84 * | | xfrm_pol_inexact_node 85 * | | | 86 * | | + root: unused 87 * | | | 88 * | | + hhead: saddr:daddr policies 89 * | | 90 * | +- coarse policies and all any:daddr policies 91 * | 92 * +---- root_s: sorted by saddr:prefix 93 * | | 94 * | xfrm_pol_inexact_node 95 * | | 96 * | + root: unused 97 * | | 98 * | + hhead: saddr:any policies 99 * | 100 * +---- coarse policies and all any:any policies 101 * 102 * Lookups return four candidate lists: 103 * 1. any:any list from top-level xfrm_pol_inexact_bin 104 * 2. any:daddr list from daddr tree 105 * 3. saddr:daddr list from 2nd level daddr tree 106 * 4. saddr:any list from saddr tree 107 * 108 * This result set then needs to be searched for the policy with 109 * the lowest priority. If two results have same prio, youngest one wins. 110 */ 111 112 struct xfrm_pol_inexact_key { 113 possible_net_t net; 114 u32 if_id; 115 u16 family; 116 u8 dir, type; 117 }; 118 119 struct xfrm_pol_inexact_bin { 120 struct xfrm_pol_inexact_key k; 121 struct rhash_head head; 122 /* list containing '*:*' policies */ 123 struct hlist_head hhead; 124 125 seqcount_spinlock_t count; 126 /* tree sorted by daddr/prefix */ 127 struct rb_root root_d; 128 129 /* tree sorted by saddr/prefix */ 130 struct rb_root root_s; 131 132 /* slow path below */ 133 struct list_head inexact_bins; 134 struct rcu_head rcu; 135 }; 136 137 enum xfrm_pol_inexact_candidate_type { 138 XFRM_POL_CAND_BOTH, 139 XFRM_POL_CAND_SADDR, 140 XFRM_POL_CAND_DADDR, 141 XFRM_POL_CAND_ANY, 142 143 XFRM_POL_CAND_MAX, 144 }; 145 146 struct xfrm_pol_inexact_candidates { 147 struct hlist_head *res[XFRM_POL_CAND_MAX]; 148 }; 149 150 static DEFINE_SPINLOCK(xfrm_if_cb_lock); 151 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 152 153 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 154 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 155 __read_mostly; 156 157 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 158 159 static struct rhashtable xfrm_policy_inexact_table; 160 static const struct rhashtable_params xfrm_pol_inexact_params; 161 162 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 163 static int stale_bundle(struct dst_entry *dst); 164 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 165 static void xfrm_policy_queue_process(struct timer_list *t); 166 167 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 168 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 169 int dir); 170 171 static struct xfrm_pol_inexact_bin * 172 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, 173 u32 if_id); 174 175 static struct xfrm_pol_inexact_bin * 176 xfrm_policy_inexact_lookup_rcu(struct net *net, 177 u8 type, u16 family, u8 dir, u32 if_id); 178 static struct xfrm_policy * 179 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, 180 bool excl); 181 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 182 struct xfrm_policy *policy); 183 184 static bool 185 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 186 struct xfrm_pol_inexact_bin *b, 187 const xfrm_address_t *saddr, 188 const xfrm_address_t *daddr); 189 190 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 191 { 192 return refcount_inc_not_zero(&policy->refcnt); 193 } 194 195 static inline bool 196 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 197 { 198 const struct flowi4 *fl4 = &fl->u.ip4; 199 200 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 201 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 202 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 203 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 204 (fl4->flowi4_proto == sel->proto || !sel->proto) && 205 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 206 } 207 208 static inline bool 209 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 210 { 211 const struct flowi6 *fl6 = &fl->u.ip6; 212 213 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 214 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 215 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 216 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 217 (fl6->flowi6_proto == sel->proto || !sel->proto) && 218 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 219 } 220 221 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 222 unsigned short family) 223 { 224 switch (family) { 225 case AF_INET: 226 return __xfrm4_selector_match(sel, fl); 227 case AF_INET6: 228 return __xfrm6_selector_match(sel, fl); 229 } 230 return false; 231 } 232 233 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 234 { 235 const struct xfrm_policy_afinfo *afinfo; 236 237 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 238 return NULL; 239 rcu_read_lock(); 240 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 241 if (unlikely(!afinfo)) 242 rcu_read_unlock(); 243 return afinfo; 244 } 245 246 /* Called with rcu_read_lock(). */ 247 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 248 { 249 return rcu_dereference(xfrm_if_cb); 250 } 251 252 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 253 const xfrm_address_t *saddr, 254 const xfrm_address_t *daddr, 255 int family, u32 mark) 256 { 257 const struct xfrm_policy_afinfo *afinfo; 258 struct dst_entry *dst; 259 260 afinfo = xfrm_policy_get_afinfo(family); 261 if (unlikely(afinfo == NULL)) 262 return ERR_PTR(-EAFNOSUPPORT); 263 264 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 265 266 rcu_read_unlock(); 267 268 return dst; 269 } 270 EXPORT_SYMBOL(__xfrm_dst_lookup); 271 272 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 273 int tos, int oif, 274 xfrm_address_t *prev_saddr, 275 xfrm_address_t *prev_daddr, 276 int family, u32 mark) 277 { 278 struct net *net = xs_net(x); 279 xfrm_address_t *saddr = &x->props.saddr; 280 xfrm_address_t *daddr = &x->id.daddr; 281 struct dst_entry *dst; 282 283 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 284 saddr = x->coaddr; 285 daddr = prev_daddr; 286 } 287 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 288 saddr = prev_saddr; 289 daddr = x->coaddr; 290 } 291 292 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 293 294 if (!IS_ERR(dst)) { 295 if (prev_saddr != saddr) 296 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 297 if (prev_daddr != daddr) 298 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 299 } 300 301 return dst; 302 } 303 304 static inline unsigned long make_jiffies(long secs) 305 { 306 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 307 return MAX_SCHEDULE_TIMEOUT-1; 308 else 309 return secs*HZ; 310 } 311 312 static void xfrm_policy_timer(struct timer_list *t) 313 { 314 struct xfrm_policy *xp = from_timer(xp, t, timer); 315 time64_t now = ktime_get_real_seconds(); 316 time64_t next = TIME64_MAX; 317 int warn = 0; 318 int dir; 319 320 read_lock(&xp->lock); 321 322 if (unlikely(xp->walk.dead)) 323 goto out; 324 325 dir = xfrm_policy_id2dir(xp->index); 326 327 if (xp->lft.hard_add_expires_seconds) { 328 time64_t tmo = xp->lft.hard_add_expires_seconds + 329 xp->curlft.add_time - now; 330 if (tmo <= 0) 331 goto expired; 332 if (tmo < next) 333 next = tmo; 334 } 335 if (xp->lft.hard_use_expires_seconds) { 336 time64_t tmo = xp->lft.hard_use_expires_seconds + 337 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 338 if (tmo <= 0) 339 goto expired; 340 if (tmo < next) 341 next = tmo; 342 } 343 if (xp->lft.soft_add_expires_seconds) { 344 time64_t tmo = xp->lft.soft_add_expires_seconds + 345 xp->curlft.add_time - now; 346 if (tmo <= 0) { 347 warn = 1; 348 tmo = XFRM_KM_TIMEOUT; 349 } 350 if (tmo < next) 351 next = tmo; 352 } 353 if (xp->lft.soft_use_expires_seconds) { 354 time64_t tmo = xp->lft.soft_use_expires_seconds + 355 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 356 if (tmo <= 0) { 357 warn = 1; 358 tmo = XFRM_KM_TIMEOUT; 359 } 360 if (tmo < next) 361 next = tmo; 362 } 363 364 if (warn) 365 km_policy_expired(xp, dir, 0, 0); 366 if (next != TIME64_MAX && 367 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 368 xfrm_pol_hold(xp); 369 370 out: 371 read_unlock(&xp->lock); 372 xfrm_pol_put(xp); 373 return; 374 375 expired: 376 read_unlock(&xp->lock); 377 if (!xfrm_policy_delete(xp, dir)) 378 km_policy_expired(xp, dir, 1, 0); 379 xfrm_pol_put(xp); 380 } 381 382 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 383 * SPD calls. 384 */ 385 386 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 387 { 388 struct xfrm_policy *policy; 389 390 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 391 392 if (policy) { 393 write_pnet(&policy->xp_net, net); 394 INIT_LIST_HEAD(&policy->walk.all); 395 INIT_HLIST_NODE(&policy->bydst_inexact_list); 396 INIT_HLIST_NODE(&policy->bydst); 397 INIT_HLIST_NODE(&policy->byidx); 398 rwlock_init(&policy->lock); 399 refcount_set(&policy->refcnt, 1); 400 skb_queue_head_init(&policy->polq.hold_queue); 401 timer_setup(&policy->timer, xfrm_policy_timer, 0); 402 timer_setup(&policy->polq.hold_timer, 403 xfrm_policy_queue_process, 0); 404 } 405 return policy; 406 } 407 EXPORT_SYMBOL(xfrm_policy_alloc); 408 409 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 410 { 411 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 412 413 security_xfrm_policy_free(policy->security); 414 kfree(policy); 415 } 416 417 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 418 419 void xfrm_policy_destroy(struct xfrm_policy *policy) 420 { 421 BUG_ON(!policy->walk.dead); 422 423 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 424 BUG(); 425 426 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 427 } 428 EXPORT_SYMBOL(xfrm_policy_destroy); 429 430 /* Rule must be locked. Release descendant resources, announce 431 * entry dead. The rule must be unlinked from lists to the moment. 432 */ 433 434 static void xfrm_policy_kill(struct xfrm_policy *policy) 435 { 436 write_lock_bh(&policy->lock); 437 policy->walk.dead = 1; 438 write_unlock_bh(&policy->lock); 439 440 atomic_inc(&policy->genid); 441 442 if (del_timer(&policy->polq.hold_timer)) 443 xfrm_pol_put(policy); 444 skb_queue_purge(&policy->polq.hold_queue); 445 446 if (del_timer(&policy->timer)) 447 xfrm_pol_put(policy); 448 449 xfrm_pol_put(policy); 450 } 451 452 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 453 454 static inline unsigned int idx_hash(struct net *net, u32 index) 455 { 456 return __idx_hash(index, net->xfrm.policy_idx_hmask); 457 } 458 459 /* calculate policy hash thresholds */ 460 static void __get_hash_thresh(struct net *net, 461 unsigned short family, int dir, 462 u8 *dbits, u8 *sbits) 463 { 464 switch (family) { 465 case AF_INET: 466 *dbits = net->xfrm.policy_bydst[dir].dbits4; 467 *sbits = net->xfrm.policy_bydst[dir].sbits4; 468 break; 469 470 case AF_INET6: 471 *dbits = net->xfrm.policy_bydst[dir].dbits6; 472 *sbits = net->xfrm.policy_bydst[dir].sbits6; 473 break; 474 475 default: 476 *dbits = 0; 477 *sbits = 0; 478 } 479 } 480 481 static struct hlist_head *policy_hash_bysel(struct net *net, 482 const struct xfrm_selector *sel, 483 unsigned short family, int dir) 484 { 485 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 486 unsigned int hash; 487 u8 dbits; 488 u8 sbits; 489 490 __get_hash_thresh(net, family, dir, &dbits, &sbits); 491 hash = __sel_hash(sel, family, hmask, dbits, sbits); 492 493 if (hash == hmask + 1) 494 return NULL; 495 496 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 497 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 498 } 499 500 static struct hlist_head *policy_hash_direct(struct net *net, 501 const xfrm_address_t *daddr, 502 const xfrm_address_t *saddr, 503 unsigned short family, int dir) 504 { 505 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 506 unsigned int hash; 507 u8 dbits; 508 u8 sbits; 509 510 __get_hash_thresh(net, family, dir, &dbits, &sbits); 511 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 512 513 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 514 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 515 } 516 517 static void xfrm_dst_hash_transfer(struct net *net, 518 struct hlist_head *list, 519 struct hlist_head *ndsttable, 520 unsigned int nhashmask, 521 int dir) 522 { 523 struct hlist_node *tmp, *entry0 = NULL; 524 struct xfrm_policy *pol; 525 unsigned int h0 = 0; 526 u8 dbits; 527 u8 sbits; 528 529 redo: 530 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 531 unsigned int h; 532 533 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 534 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 535 pol->family, nhashmask, dbits, sbits); 536 if (!entry0) { 537 hlist_del_rcu(&pol->bydst); 538 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 539 h0 = h; 540 } else { 541 if (h != h0) 542 continue; 543 hlist_del_rcu(&pol->bydst); 544 hlist_add_behind_rcu(&pol->bydst, entry0); 545 } 546 entry0 = &pol->bydst; 547 } 548 if (!hlist_empty(list)) { 549 entry0 = NULL; 550 goto redo; 551 } 552 } 553 554 static void xfrm_idx_hash_transfer(struct hlist_head *list, 555 struct hlist_head *nidxtable, 556 unsigned int nhashmask) 557 { 558 struct hlist_node *tmp; 559 struct xfrm_policy *pol; 560 561 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 562 unsigned int h; 563 564 h = __idx_hash(pol->index, nhashmask); 565 hlist_add_head(&pol->byidx, nidxtable+h); 566 } 567 } 568 569 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 570 { 571 return ((old_hmask + 1) << 1) - 1; 572 } 573 574 static void xfrm_bydst_resize(struct net *net, int dir) 575 { 576 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 577 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 578 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 579 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 580 struct hlist_head *odst; 581 int i; 582 583 if (!ndst) 584 return; 585 586 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 587 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 588 589 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 590 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 591 592 for (i = hmask; i >= 0; i--) 593 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 594 595 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 596 net->xfrm.policy_bydst[dir].hmask = nhashmask; 597 598 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 599 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 600 601 synchronize_rcu(); 602 603 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 604 } 605 606 static void xfrm_byidx_resize(struct net *net, int total) 607 { 608 unsigned int hmask = net->xfrm.policy_idx_hmask; 609 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 610 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 611 struct hlist_head *oidx = net->xfrm.policy_byidx; 612 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 613 int i; 614 615 if (!nidx) 616 return; 617 618 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 619 620 for (i = hmask; i >= 0; i--) 621 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 622 623 net->xfrm.policy_byidx = nidx; 624 net->xfrm.policy_idx_hmask = nhashmask; 625 626 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 627 628 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 629 } 630 631 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 632 { 633 unsigned int cnt = net->xfrm.policy_count[dir]; 634 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 635 636 if (total) 637 *total += cnt; 638 639 if ((hmask + 1) < xfrm_policy_hashmax && 640 cnt > hmask) 641 return 1; 642 643 return 0; 644 } 645 646 static inline int xfrm_byidx_should_resize(struct net *net, int total) 647 { 648 unsigned int hmask = net->xfrm.policy_idx_hmask; 649 650 if ((hmask + 1) < xfrm_policy_hashmax && 651 total > hmask) 652 return 1; 653 654 return 0; 655 } 656 657 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 658 { 659 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 660 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 661 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 662 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 663 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 664 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 665 si->spdhcnt = net->xfrm.policy_idx_hmask; 666 si->spdhmcnt = xfrm_policy_hashmax; 667 } 668 EXPORT_SYMBOL(xfrm_spd_getinfo); 669 670 static DEFINE_MUTEX(hash_resize_mutex); 671 static void xfrm_hash_resize(struct work_struct *work) 672 { 673 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 674 int dir, total; 675 676 mutex_lock(&hash_resize_mutex); 677 678 total = 0; 679 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 680 if (xfrm_bydst_should_resize(net, dir, &total)) 681 xfrm_bydst_resize(net, dir); 682 } 683 if (xfrm_byidx_should_resize(net, total)) 684 xfrm_byidx_resize(net, total); 685 686 mutex_unlock(&hash_resize_mutex); 687 } 688 689 /* Make sure *pol can be inserted into fastbin. 690 * Useful to check that later insert requests will be successful 691 * (provided xfrm_policy_lock is held throughout). 692 */ 693 static struct xfrm_pol_inexact_bin * 694 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) 695 { 696 struct xfrm_pol_inexact_bin *bin, *prev; 697 struct xfrm_pol_inexact_key k = { 698 .family = pol->family, 699 .type = pol->type, 700 .dir = dir, 701 .if_id = pol->if_id, 702 }; 703 struct net *net = xp_net(pol); 704 705 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 706 707 write_pnet(&k.net, net); 708 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, 709 xfrm_pol_inexact_params); 710 if (bin) 711 return bin; 712 713 bin = kzalloc(sizeof(*bin), GFP_ATOMIC); 714 if (!bin) 715 return NULL; 716 717 bin->k = k; 718 INIT_HLIST_HEAD(&bin->hhead); 719 bin->root_d = RB_ROOT; 720 bin->root_s = RB_ROOT; 721 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); 722 723 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, 724 &bin->k, &bin->head, 725 xfrm_pol_inexact_params); 726 if (!prev) { 727 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); 728 return bin; 729 } 730 731 kfree(bin); 732 733 return IS_ERR(prev) ? NULL : prev; 734 } 735 736 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, 737 int family, u8 prefixlen) 738 { 739 if (xfrm_addr_any(addr, family)) 740 return true; 741 742 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) 743 return true; 744 745 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) 746 return true; 747 748 return false; 749 } 750 751 static bool 752 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) 753 { 754 const xfrm_address_t *addr; 755 bool saddr_any, daddr_any; 756 u8 prefixlen; 757 758 addr = &policy->selector.saddr; 759 prefixlen = policy->selector.prefixlen_s; 760 761 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 762 policy->family, 763 prefixlen); 764 addr = &policy->selector.daddr; 765 prefixlen = policy->selector.prefixlen_d; 766 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 767 policy->family, 768 prefixlen); 769 return saddr_any && daddr_any; 770 } 771 772 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, 773 const xfrm_address_t *addr, u8 prefixlen) 774 { 775 node->addr = *addr; 776 node->prefixlen = prefixlen; 777 } 778 779 static struct xfrm_pol_inexact_node * 780 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) 781 { 782 struct xfrm_pol_inexact_node *node; 783 784 node = kzalloc(sizeof(*node), GFP_ATOMIC); 785 if (node) 786 xfrm_pol_inexact_node_init(node, addr, prefixlen); 787 788 return node; 789 } 790 791 static int xfrm_policy_addr_delta(const xfrm_address_t *a, 792 const xfrm_address_t *b, 793 u8 prefixlen, u16 family) 794 { 795 u32 ma, mb, mask; 796 unsigned int pdw, pbi; 797 int delta = 0; 798 799 switch (family) { 800 case AF_INET: 801 if (prefixlen == 0) 802 return 0; 803 mask = ~0U << (32 - prefixlen); 804 ma = ntohl(a->a4) & mask; 805 mb = ntohl(b->a4) & mask; 806 if (ma < mb) 807 delta = -1; 808 else if (ma > mb) 809 delta = 1; 810 break; 811 case AF_INET6: 812 pdw = prefixlen >> 5; 813 pbi = prefixlen & 0x1f; 814 815 if (pdw) { 816 delta = memcmp(a->a6, b->a6, pdw << 2); 817 if (delta) 818 return delta; 819 } 820 if (pbi) { 821 mask = ~0U << (32 - pbi); 822 ma = ntohl(a->a6[pdw]) & mask; 823 mb = ntohl(b->a6[pdw]) & mask; 824 if (ma < mb) 825 delta = -1; 826 else if (ma > mb) 827 delta = 1; 828 } 829 break; 830 default: 831 break; 832 } 833 834 return delta; 835 } 836 837 static void xfrm_policy_inexact_list_reinsert(struct net *net, 838 struct xfrm_pol_inexact_node *n, 839 u16 family) 840 { 841 unsigned int matched_s, matched_d; 842 struct xfrm_policy *policy, *p; 843 844 matched_s = 0; 845 matched_d = 0; 846 847 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 848 struct hlist_node *newpos = NULL; 849 bool matches_s, matches_d; 850 851 if (!policy->bydst_reinsert) 852 continue; 853 854 WARN_ON_ONCE(policy->family != family); 855 856 policy->bydst_reinsert = false; 857 hlist_for_each_entry(p, &n->hhead, bydst) { 858 if (policy->priority > p->priority) 859 newpos = &p->bydst; 860 else if (policy->priority == p->priority && 861 policy->pos > p->pos) 862 newpos = &p->bydst; 863 else 864 break; 865 } 866 867 if (newpos) 868 hlist_add_behind_rcu(&policy->bydst, newpos); 869 else 870 hlist_add_head_rcu(&policy->bydst, &n->hhead); 871 872 /* paranoia checks follow. 873 * Check that the reinserted policy matches at least 874 * saddr or daddr for current node prefix. 875 * 876 * Matching both is fine, matching saddr in one policy 877 * (but not daddr) and then matching only daddr in another 878 * is a bug. 879 */ 880 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 881 &n->addr, 882 n->prefixlen, 883 family) == 0; 884 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 885 &n->addr, 886 n->prefixlen, 887 family) == 0; 888 if (matches_s && matches_d) 889 continue; 890 891 WARN_ON_ONCE(!matches_s && !matches_d); 892 if (matches_s) 893 matched_s++; 894 if (matches_d) 895 matched_d++; 896 WARN_ON_ONCE(matched_s && matched_d); 897 } 898 } 899 900 static void xfrm_policy_inexact_node_reinsert(struct net *net, 901 struct xfrm_pol_inexact_node *n, 902 struct rb_root *new, 903 u16 family) 904 { 905 struct xfrm_pol_inexact_node *node; 906 struct rb_node **p, *parent; 907 908 /* we should not have another subtree here */ 909 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 910 restart: 911 parent = NULL; 912 p = &new->rb_node; 913 while (*p) { 914 u8 prefixlen; 915 int delta; 916 917 parent = *p; 918 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 919 920 prefixlen = min(node->prefixlen, n->prefixlen); 921 922 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 923 prefixlen, family); 924 if (delta < 0) { 925 p = &parent->rb_left; 926 } else if (delta > 0) { 927 p = &parent->rb_right; 928 } else { 929 bool same_prefixlen = node->prefixlen == n->prefixlen; 930 struct xfrm_policy *tmp; 931 932 hlist_for_each_entry(tmp, &n->hhead, bydst) { 933 tmp->bydst_reinsert = true; 934 hlist_del_rcu(&tmp->bydst); 935 } 936 937 node->prefixlen = prefixlen; 938 939 xfrm_policy_inexact_list_reinsert(net, node, family); 940 941 if (same_prefixlen) { 942 kfree_rcu(n, rcu); 943 return; 944 } 945 946 rb_erase(*p, new); 947 kfree_rcu(n, rcu); 948 n = node; 949 goto restart; 950 } 951 } 952 953 rb_link_node_rcu(&n->node, parent, p); 954 rb_insert_color(&n->node, new); 955 } 956 957 /* merge nodes v and n */ 958 static void xfrm_policy_inexact_node_merge(struct net *net, 959 struct xfrm_pol_inexact_node *v, 960 struct xfrm_pol_inexact_node *n, 961 u16 family) 962 { 963 struct xfrm_pol_inexact_node *node; 964 struct xfrm_policy *tmp; 965 struct rb_node *rnode; 966 967 /* To-be-merged node v has a subtree. 968 * 969 * Dismantle it and insert its nodes to n->root. 970 */ 971 while ((rnode = rb_first(&v->root)) != NULL) { 972 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 973 rb_erase(&node->node, &v->root); 974 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 975 family); 976 } 977 978 hlist_for_each_entry(tmp, &v->hhead, bydst) { 979 tmp->bydst_reinsert = true; 980 hlist_del_rcu(&tmp->bydst); 981 } 982 983 xfrm_policy_inexact_list_reinsert(net, n, family); 984 } 985 986 static struct xfrm_pol_inexact_node * 987 xfrm_policy_inexact_insert_node(struct net *net, 988 struct rb_root *root, 989 xfrm_address_t *addr, 990 u16 family, u8 prefixlen, u8 dir) 991 { 992 struct xfrm_pol_inexact_node *cached = NULL; 993 struct rb_node **p, *parent = NULL; 994 struct xfrm_pol_inexact_node *node; 995 996 p = &root->rb_node; 997 while (*p) { 998 int delta; 999 1000 parent = *p; 1001 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 1002 1003 delta = xfrm_policy_addr_delta(addr, &node->addr, 1004 node->prefixlen, 1005 family); 1006 if (delta == 0 && prefixlen >= node->prefixlen) { 1007 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 1008 return node; 1009 } 1010 1011 if (delta < 0) 1012 p = &parent->rb_left; 1013 else 1014 p = &parent->rb_right; 1015 1016 if (prefixlen < node->prefixlen) { 1017 delta = xfrm_policy_addr_delta(addr, &node->addr, 1018 prefixlen, 1019 family); 1020 if (delta) 1021 continue; 1022 1023 /* This node is a subnet of the new prefix. It needs 1024 * to be removed and re-inserted with the smaller 1025 * prefix and all nodes that are now also covered 1026 * by the reduced prefixlen. 1027 */ 1028 rb_erase(&node->node, root); 1029 1030 if (!cached) { 1031 xfrm_pol_inexact_node_init(node, addr, 1032 prefixlen); 1033 cached = node; 1034 } else { 1035 /* This node also falls within the new 1036 * prefixlen. Merge the to-be-reinserted 1037 * node and this one. 1038 */ 1039 xfrm_policy_inexact_node_merge(net, node, 1040 cached, family); 1041 kfree_rcu(node, rcu); 1042 } 1043 1044 /* restart */ 1045 p = &root->rb_node; 1046 parent = NULL; 1047 } 1048 } 1049 1050 node = cached; 1051 if (!node) { 1052 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1053 if (!node) 1054 return NULL; 1055 } 1056 1057 rb_link_node_rcu(&node->node, parent, p); 1058 rb_insert_color(&node->node, root); 1059 1060 return node; 1061 } 1062 1063 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1064 { 1065 struct xfrm_pol_inexact_node *node; 1066 struct rb_node *rn = rb_first(r); 1067 1068 while (rn) { 1069 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1070 1071 xfrm_policy_inexact_gc_tree(&node->root, rm); 1072 rn = rb_next(rn); 1073 1074 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1075 WARN_ON_ONCE(rm); 1076 continue; 1077 } 1078 1079 rb_erase(&node->node, r); 1080 kfree_rcu(node, rcu); 1081 } 1082 } 1083 1084 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1085 { 1086 write_seqcount_begin(&b->count); 1087 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1088 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1089 write_seqcount_end(&b->count); 1090 1091 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1092 !hlist_empty(&b->hhead)) { 1093 WARN_ON_ONCE(net_exit); 1094 return; 1095 } 1096 1097 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1098 xfrm_pol_inexact_params) == 0) { 1099 list_del(&b->inexact_bins); 1100 kfree_rcu(b, rcu); 1101 } 1102 } 1103 1104 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1105 { 1106 struct net *net = read_pnet(&b->k.net); 1107 1108 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1109 __xfrm_policy_inexact_prune_bin(b, false); 1110 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1111 } 1112 1113 static void __xfrm_policy_inexact_flush(struct net *net) 1114 { 1115 struct xfrm_pol_inexact_bin *bin, *t; 1116 1117 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1118 1119 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1120 __xfrm_policy_inexact_prune_bin(bin, false); 1121 } 1122 1123 static struct hlist_head * 1124 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1125 struct xfrm_policy *policy, u8 dir) 1126 { 1127 struct xfrm_pol_inexact_node *n; 1128 struct net *net; 1129 1130 net = xp_net(policy); 1131 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1132 1133 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1134 return &bin->hhead; 1135 1136 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1137 policy->family, 1138 policy->selector.prefixlen_d)) { 1139 write_seqcount_begin(&bin->count); 1140 n = xfrm_policy_inexact_insert_node(net, 1141 &bin->root_s, 1142 &policy->selector.saddr, 1143 policy->family, 1144 policy->selector.prefixlen_s, 1145 dir); 1146 write_seqcount_end(&bin->count); 1147 if (!n) 1148 return NULL; 1149 1150 return &n->hhead; 1151 } 1152 1153 /* daddr is fixed */ 1154 write_seqcount_begin(&bin->count); 1155 n = xfrm_policy_inexact_insert_node(net, 1156 &bin->root_d, 1157 &policy->selector.daddr, 1158 policy->family, 1159 policy->selector.prefixlen_d, dir); 1160 write_seqcount_end(&bin->count); 1161 if (!n) 1162 return NULL; 1163 1164 /* saddr is wildcard */ 1165 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1166 policy->family, 1167 policy->selector.prefixlen_s)) 1168 return &n->hhead; 1169 1170 write_seqcount_begin(&bin->count); 1171 n = xfrm_policy_inexact_insert_node(net, 1172 &n->root, 1173 &policy->selector.saddr, 1174 policy->family, 1175 policy->selector.prefixlen_s, dir); 1176 write_seqcount_end(&bin->count); 1177 if (!n) 1178 return NULL; 1179 1180 return &n->hhead; 1181 } 1182 1183 static struct xfrm_policy * 1184 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1185 { 1186 struct xfrm_pol_inexact_bin *bin; 1187 struct xfrm_policy *delpol; 1188 struct hlist_head *chain; 1189 struct net *net; 1190 1191 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1192 if (!bin) 1193 return ERR_PTR(-ENOMEM); 1194 1195 net = xp_net(policy); 1196 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1197 1198 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1199 if (!chain) { 1200 __xfrm_policy_inexact_prune_bin(bin, false); 1201 return ERR_PTR(-ENOMEM); 1202 } 1203 1204 delpol = xfrm_policy_insert_list(chain, policy, excl); 1205 if (delpol && excl) { 1206 __xfrm_policy_inexact_prune_bin(bin, false); 1207 return ERR_PTR(-EEXIST); 1208 } 1209 1210 chain = &net->xfrm.policy_inexact[dir]; 1211 xfrm_policy_insert_inexact_list(chain, policy); 1212 1213 if (delpol) 1214 __xfrm_policy_inexact_prune_bin(bin, false); 1215 1216 return delpol; 1217 } 1218 1219 static void xfrm_hash_rebuild(struct work_struct *work) 1220 { 1221 struct net *net = container_of(work, struct net, 1222 xfrm.policy_hthresh.work); 1223 unsigned int hmask; 1224 struct xfrm_policy *pol; 1225 struct xfrm_policy *policy; 1226 struct hlist_head *chain; 1227 struct hlist_head *odst; 1228 struct hlist_node *newpos; 1229 int i; 1230 int dir; 1231 unsigned seq; 1232 u8 lbits4, rbits4, lbits6, rbits6; 1233 1234 mutex_lock(&hash_resize_mutex); 1235 1236 /* read selector prefixlen thresholds */ 1237 do { 1238 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1239 1240 lbits4 = net->xfrm.policy_hthresh.lbits4; 1241 rbits4 = net->xfrm.policy_hthresh.rbits4; 1242 lbits6 = net->xfrm.policy_hthresh.lbits6; 1243 rbits6 = net->xfrm.policy_hthresh.rbits6; 1244 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1245 1246 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1247 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 1248 1249 /* make sure that we can insert the indirect policies again before 1250 * we start with destructive action. 1251 */ 1252 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1253 struct xfrm_pol_inexact_bin *bin; 1254 u8 dbits, sbits; 1255 1256 dir = xfrm_policy_id2dir(policy->index); 1257 if (policy->walk.dead || dir >= XFRM_POLICY_MAX) 1258 continue; 1259 1260 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1261 if (policy->family == AF_INET) { 1262 dbits = rbits4; 1263 sbits = lbits4; 1264 } else { 1265 dbits = rbits6; 1266 sbits = lbits6; 1267 } 1268 } else { 1269 if (policy->family == AF_INET) { 1270 dbits = lbits4; 1271 sbits = rbits4; 1272 } else { 1273 dbits = lbits6; 1274 sbits = rbits6; 1275 } 1276 } 1277 1278 if (policy->selector.prefixlen_d < dbits || 1279 policy->selector.prefixlen_s < sbits) 1280 continue; 1281 1282 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1283 if (!bin) 1284 goto out_unlock; 1285 1286 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1287 goto out_unlock; 1288 } 1289 1290 /* reset the bydst and inexact table in all directions */ 1291 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1292 struct hlist_node *n; 1293 1294 hlist_for_each_entry_safe(policy, n, 1295 &net->xfrm.policy_inexact[dir], 1296 bydst_inexact_list) { 1297 hlist_del_rcu(&policy->bydst); 1298 hlist_del_init(&policy->bydst_inexact_list); 1299 } 1300 1301 hmask = net->xfrm.policy_bydst[dir].hmask; 1302 odst = net->xfrm.policy_bydst[dir].table; 1303 for (i = hmask; i >= 0; i--) { 1304 hlist_for_each_entry_safe(policy, n, odst + i, bydst) 1305 hlist_del_rcu(&policy->bydst); 1306 } 1307 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1308 /* dir out => dst = remote, src = local */ 1309 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1310 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1311 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1312 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1313 } else { 1314 /* dir in/fwd => dst = local, src = remote */ 1315 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1316 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1317 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1318 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1319 } 1320 } 1321 1322 /* re-insert all policies by order of creation */ 1323 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1324 if (policy->walk.dead) 1325 continue; 1326 dir = xfrm_policy_id2dir(policy->index); 1327 if (dir >= XFRM_POLICY_MAX) { 1328 /* skip socket policies */ 1329 continue; 1330 } 1331 newpos = NULL; 1332 chain = policy_hash_bysel(net, &policy->selector, 1333 policy->family, dir); 1334 1335 if (!chain) { 1336 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1337 1338 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1339 continue; 1340 } 1341 1342 hlist_for_each_entry(pol, chain, bydst) { 1343 if (policy->priority >= pol->priority) 1344 newpos = &pol->bydst; 1345 else 1346 break; 1347 } 1348 if (newpos) 1349 hlist_add_behind_rcu(&policy->bydst, newpos); 1350 else 1351 hlist_add_head_rcu(&policy->bydst, chain); 1352 } 1353 1354 out_unlock: 1355 __xfrm_policy_inexact_flush(net); 1356 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 1357 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1358 1359 mutex_unlock(&hash_resize_mutex); 1360 } 1361 1362 void xfrm_policy_hash_rebuild(struct net *net) 1363 { 1364 schedule_work(&net->xfrm.policy_hthresh.work); 1365 } 1366 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1367 1368 /* Generate new index... KAME seems to generate them ordered by cost 1369 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1370 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1371 { 1372 static u32 idx_generator; 1373 1374 for (;;) { 1375 struct hlist_head *list; 1376 struct xfrm_policy *p; 1377 u32 idx; 1378 int found; 1379 1380 if (!index) { 1381 idx = (idx_generator | dir); 1382 idx_generator += 8; 1383 } else { 1384 idx = index; 1385 index = 0; 1386 } 1387 1388 if (idx == 0) 1389 idx = 8; 1390 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1391 found = 0; 1392 hlist_for_each_entry(p, list, byidx) { 1393 if (p->index == idx) { 1394 found = 1; 1395 break; 1396 } 1397 } 1398 if (!found) 1399 return idx; 1400 } 1401 } 1402 1403 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1404 { 1405 u32 *p1 = (u32 *) s1; 1406 u32 *p2 = (u32 *) s2; 1407 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1408 int i; 1409 1410 for (i = 0; i < len; i++) { 1411 if (p1[i] != p2[i]) 1412 return 1; 1413 } 1414 1415 return 0; 1416 } 1417 1418 static void xfrm_policy_requeue(struct xfrm_policy *old, 1419 struct xfrm_policy *new) 1420 { 1421 struct xfrm_policy_queue *pq = &old->polq; 1422 struct sk_buff_head list; 1423 1424 if (skb_queue_empty(&pq->hold_queue)) 1425 return; 1426 1427 __skb_queue_head_init(&list); 1428 1429 spin_lock_bh(&pq->hold_queue.lock); 1430 skb_queue_splice_init(&pq->hold_queue, &list); 1431 if (del_timer(&pq->hold_timer)) 1432 xfrm_pol_put(old); 1433 spin_unlock_bh(&pq->hold_queue.lock); 1434 1435 pq = &new->polq; 1436 1437 spin_lock_bh(&pq->hold_queue.lock); 1438 skb_queue_splice(&list, &pq->hold_queue); 1439 pq->timeout = XFRM_QUEUE_TMO_MIN; 1440 if (!mod_timer(&pq->hold_timer, jiffies)) 1441 xfrm_pol_hold(new); 1442 spin_unlock_bh(&pq->hold_queue.lock); 1443 } 1444 1445 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark, 1446 struct xfrm_policy *pol) 1447 { 1448 return mark->v == pol->mark.v && mark->m == pol->mark.m; 1449 } 1450 1451 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1452 { 1453 const struct xfrm_pol_inexact_key *k = data; 1454 u32 a = k->type << 24 | k->dir << 16 | k->family; 1455 1456 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1457 seed); 1458 } 1459 1460 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1461 { 1462 const struct xfrm_pol_inexact_bin *b = data; 1463 1464 return xfrm_pol_bin_key(&b->k, 0, seed); 1465 } 1466 1467 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1468 const void *ptr) 1469 { 1470 const struct xfrm_pol_inexact_key *key = arg->key; 1471 const struct xfrm_pol_inexact_bin *b = ptr; 1472 int ret; 1473 1474 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1475 return -1; 1476 1477 ret = b->k.dir ^ key->dir; 1478 if (ret) 1479 return ret; 1480 1481 ret = b->k.type ^ key->type; 1482 if (ret) 1483 return ret; 1484 1485 ret = b->k.family ^ key->family; 1486 if (ret) 1487 return ret; 1488 1489 return b->k.if_id ^ key->if_id; 1490 } 1491 1492 static const struct rhashtable_params xfrm_pol_inexact_params = { 1493 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1494 .hashfn = xfrm_pol_bin_key, 1495 .obj_hashfn = xfrm_pol_bin_obj, 1496 .obj_cmpfn = xfrm_pol_bin_cmp, 1497 .automatic_shrinking = true, 1498 }; 1499 1500 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1501 struct xfrm_policy *policy) 1502 { 1503 struct xfrm_policy *pol, *delpol = NULL; 1504 struct hlist_node *newpos = NULL; 1505 int i = 0; 1506 1507 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1508 if (pol->type == policy->type && 1509 pol->if_id == policy->if_id && 1510 !selector_cmp(&pol->selector, &policy->selector) && 1511 xfrm_policy_mark_match(&policy->mark, pol) && 1512 xfrm_sec_ctx_match(pol->security, policy->security) && 1513 !WARN_ON(delpol)) { 1514 delpol = pol; 1515 if (policy->priority > pol->priority) 1516 continue; 1517 } else if (policy->priority >= pol->priority) { 1518 newpos = &pol->bydst_inexact_list; 1519 continue; 1520 } 1521 if (delpol) 1522 break; 1523 } 1524 1525 if (newpos) 1526 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1527 else 1528 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1529 1530 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1531 pol->pos = i; 1532 i++; 1533 } 1534 } 1535 1536 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1537 struct xfrm_policy *policy, 1538 bool excl) 1539 { 1540 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1541 1542 hlist_for_each_entry(pol, chain, bydst) { 1543 if (pol->type == policy->type && 1544 pol->if_id == policy->if_id && 1545 !selector_cmp(&pol->selector, &policy->selector) && 1546 xfrm_policy_mark_match(&policy->mark, pol) && 1547 xfrm_sec_ctx_match(pol->security, policy->security) && 1548 !WARN_ON(delpol)) { 1549 if (excl) 1550 return ERR_PTR(-EEXIST); 1551 delpol = pol; 1552 if (policy->priority > pol->priority) 1553 continue; 1554 } else if (policy->priority >= pol->priority) { 1555 newpos = pol; 1556 continue; 1557 } 1558 if (delpol) 1559 break; 1560 } 1561 1562 if (newpos) 1563 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1564 else 1565 hlist_add_head_rcu(&policy->bydst, chain); 1566 1567 return delpol; 1568 } 1569 1570 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1571 { 1572 struct net *net = xp_net(policy); 1573 struct xfrm_policy *delpol; 1574 struct hlist_head *chain; 1575 1576 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1577 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1578 if (chain) 1579 delpol = xfrm_policy_insert_list(chain, policy, excl); 1580 else 1581 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1582 1583 if (IS_ERR(delpol)) { 1584 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1585 return PTR_ERR(delpol); 1586 } 1587 1588 __xfrm_policy_link(policy, dir); 1589 1590 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1591 if (policy->family == AF_INET) 1592 rt_genid_bump_ipv4(net); 1593 else 1594 rt_genid_bump_ipv6(net); 1595 1596 if (delpol) { 1597 xfrm_policy_requeue(delpol, policy); 1598 __xfrm_policy_unlink(delpol, dir); 1599 } 1600 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1601 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1602 policy->curlft.add_time = ktime_get_real_seconds(); 1603 policy->curlft.use_time = 0; 1604 if (!mod_timer(&policy->timer, jiffies + HZ)) 1605 xfrm_pol_hold(policy); 1606 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1607 1608 if (delpol) 1609 xfrm_policy_kill(delpol); 1610 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1611 schedule_work(&net->xfrm.policy_hash_work); 1612 1613 return 0; 1614 } 1615 EXPORT_SYMBOL(xfrm_policy_insert); 1616 1617 static struct xfrm_policy * 1618 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark, 1619 u32 if_id, u8 type, int dir, struct xfrm_selector *sel, 1620 struct xfrm_sec_ctx *ctx) 1621 { 1622 struct xfrm_policy *pol; 1623 1624 if (!chain) 1625 return NULL; 1626 1627 hlist_for_each_entry(pol, chain, bydst) { 1628 if (pol->type == type && 1629 pol->if_id == if_id && 1630 xfrm_policy_mark_match(mark, pol) && 1631 !selector_cmp(sel, &pol->selector) && 1632 xfrm_sec_ctx_match(ctx, pol->security)) 1633 return pol; 1634 } 1635 1636 return NULL; 1637 } 1638 1639 struct xfrm_policy * 1640 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1641 u8 type, int dir, struct xfrm_selector *sel, 1642 struct xfrm_sec_ctx *ctx, int delete, int *err) 1643 { 1644 struct xfrm_pol_inexact_bin *bin = NULL; 1645 struct xfrm_policy *pol, *ret = NULL; 1646 struct hlist_head *chain; 1647 1648 *err = 0; 1649 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1650 chain = policy_hash_bysel(net, sel, sel->family, dir); 1651 if (!chain) { 1652 struct xfrm_pol_inexact_candidates cand; 1653 int i; 1654 1655 bin = xfrm_policy_inexact_lookup(net, type, 1656 sel->family, dir, if_id); 1657 if (!bin) { 1658 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1659 return NULL; 1660 } 1661 1662 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1663 &sel->saddr, 1664 &sel->daddr)) { 1665 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1666 return NULL; 1667 } 1668 1669 pol = NULL; 1670 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1671 struct xfrm_policy *tmp; 1672 1673 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1674 if_id, type, dir, 1675 sel, ctx); 1676 if (!tmp) 1677 continue; 1678 1679 if (!pol || tmp->pos < pol->pos) 1680 pol = tmp; 1681 } 1682 } else { 1683 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1684 sel, ctx); 1685 } 1686 1687 if (pol) { 1688 xfrm_pol_hold(pol); 1689 if (delete) { 1690 *err = security_xfrm_policy_delete(pol->security); 1691 if (*err) { 1692 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1693 return pol; 1694 } 1695 __xfrm_policy_unlink(pol, dir); 1696 } 1697 ret = pol; 1698 } 1699 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1700 1701 if (ret && delete) 1702 xfrm_policy_kill(ret); 1703 if (bin && delete) 1704 xfrm_policy_inexact_prune_bin(bin); 1705 return ret; 1706 } 1707 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1708 1709 struct xfrm_policy * 1710 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1711 u8 type, int dir, u32 id, int delete, int *err) 1712 { 1713 struct xfrm_policy *pol, *ret; 1714 struct hlist_head *chain; 1715 1716 *err = -ENOENT; 1717 if (xfrm_policy_id2dir(id) != dir) 1718 return NULL; 1719 1720 *err = 0; 1721 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1722 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1723 ret = NULL; 1724 hlist_for_each_entry(pol, chain, byidx) { 1725 if (pol->type == type && pol->index == id && 1726 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) { 1727 xfrm_pol_hold(pol); 1728 if (delete) { 1729 *err = security_xfrm_policy_delete( 1730 pol->security); 1731 if (*err) { 1732 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1733 return pol; 1734 } 1735 __xfrm_policy_unlink(pol, dir); 1736 } 1737 ret = pol; 1738 break; 1739 } 1740 } 1741 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1742 1743 if (ret && delete) 1744 xfrm_policy_kill(ret); 1745 return ret; 1746 } 1747 EXPORT_SYMBOL(xfrm_policy_byid); 1748 1749 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1750 static inline int 1751 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1752 { 1753 struct xfrm_policy *pol; 1754 int err = 0; 1755 1756 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1757 if (pol->walk.dead || 1758 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1759 pol->type != type) 1760 continue; 1761 1762 err = security_xfrm_policy_delete(pol->security); 1763 if (err) { 1764 xfrm_audit_policy_delete(pol, 0, task_valid); 1765 return err; 1766 } 1767 } 1768 return err; 1769 } 1770 #else 1771 static inline int 1772 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1773 { 1774 return 0; 1775 } 1776 #endif 1777 1778 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1779 { 1780 int dir, err = 0, cnt = 0; 1781 struct xfrm_policy *pol; 1782 1783 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1784 1785 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1786 if (err) 1787 goto out; 1788 1789 again: 1790 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1791 dir = xfrm_policy_id2dir(pol->index); 1792 if (pol->walk.dead || 1793 dir >= XFRM_POLICY_MAX || 1794 pol->type != type) 1795 continue; 1796 1797 __xfrm_policy_unlink(pol, dir); 1798 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1799 cnt++; 1800 xfrm_audit_policy_delete(pol, 1, task_valid); 1801 xfrm_policy_kill(pol); 1802 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1803 goto again; 1804 } 1805 if (cnt) 1806 __xfrm_policy_inexact_flush(net); 1807 else 1808 err = -ESRCH; 1809 out: 1810 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1811 return err; 1812 } 1813 EXPORT_SYMBOL(xfrm_policy_flush); 1814 1815 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1816 int (*func)(struct xfrm_policy *, int, int, void*), 1817 void *data) 1818 { 1819 struct xfrm_policy *pol; 1820 struct xfrm_policy_walk_entry *x; 1821 int error = 0; 1822 1823 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1824 walk->type != XFRM_POLICY_TYPE_ANY) 1825 return -EINVAL; 1826 1827 if (list_empty(&walk->walk.all) && walk->seq != 0) 1828 return 0; 1829 1830 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1831 if (list_empty(&walk->walk.all)) 1832 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1833 else 1834 x = list_first_entry(&walk->walk.all, 1835 struct xfrm_policy_walk_entry, all); 1836 1837 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1838 if (x->dead) 1839 continue; 1840 pol = container_of(x, struct xfrm_policy, walk); 1841 if (walk->type != XFRM_POLICY_TYPE_ANY && 1842 walk->type != pol->type) 1843 continue; 1844 error = func(pol, xfrm_policy_id2dir(pol->index), 1845 walk->seq, data); 1846 if (error) { 1847 list_move_tail(&walk->walk.all, &x->all); 1848 goto out; 1849 } 1850 walk->seq++; 1851 } 1852 if (walk->seq == 0) { 1853 error = -ENOENT; 1854 goto out; 1855 } 1856 list_del_init(&walk->walk.all); 1857 out: 1858 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1859 return error; 1860 } 1861 EXPORT_SYMBOL(xfrm_policy_walk); 1862 1863 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1864 { 1865 INIT_LIST_HEAD(&walk->walk.all); 1866 walk->walk.dead = 1; 1867 walk->type = type; 1868 walk->seq = 0; 1869 } 1870 EXPORT_SYMBOL(xfrm_policy_walk_init); 1871 1872 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1873 { 1874 if (list_empty(&walk->walk.all)) 1875 return; 1876 1877 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1878 list_del(&walk->walk.all); 1879 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1880 } 1881 EXPORT_SYMBOL(xfrm_policy_walk_done); 1882 1883 /* 1884 * Find policy to apply to this flow. 1885 * 1886 * Returns 0 if policy found, else an -errno. 1887 */ 1888 static int xfrm_policy_match(const struct xfrm_policy *pol, 1889 const struct flowi *fl, 1890 u8 type, u16 family, int dir, u32 if_id) 1891 { 1892 const struct xfrm_selector *sel = &pol->selector; 1893 int ret = -ESRCH; 1894 bool match; 1895 1896 if (pol->family != family || 1897 pol->if_id != if_id || 1898 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1899 pol->type != type) 1900 return ret; 1901 1902 match = xfrm_selector_match(sel, fl, family); 1903 if (match) 1904 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid); 1905 return ret; 1906 } 1907 1908 static struct xfrm_pol_inexact_node * 1909 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1910 seqcount_spinlock_t *count, 1911 const xfrm_address_t *addr, u16 family) 1912 { 1913 const struct rb_node *parent; 1914 int seq; 1915 1916 again: 1917 seq = read_seqcount_begin(count); 1918 1919 parent = rcu_dereference_raw(r->rb_node); 1920 while (parent) { 1921 struct xfrm_pol_inexact_node *node; 1922 int delta; 1923 1924 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1925 1926 delta = xfrm_policy_addr_delta(addr, &node->addr, 1927 node->prefixlen, family); 1928 if (delta < 0) { 1929 parent = rcu_dereference_raw(parent->rb_left); 1930 continue; 1931 } else if (delta > 0) { 1932 parent = rcu_dereference_raw(parent->rb_right); 1933 continue; 1934 } 1935 1936 return node; 1937 } 1938 1939 if (read_seqcount_retry(count, seq)) 1940 goto again; 1941 1942 return NULL; 1943 } 1944 1945 static bool 1946 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1947 struct xfrm_pol_inexact_bin *b, 1948 const xfrm_address_t *saddr, 1949 const xfrm_address_t *daddr) 1950 { 1951 struct xfrm_pol_inexact_node *n; 1952 u16 family; 1953 1954 if (!b) 1955 return false; 1956 1957 family = b->k.family; 1958 memset(cand, 0, sizeof(*cand)); 1959 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1960 1961 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1962 family); 1963 if (n) { 1964 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1965 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1966 family); 1967 if (n) 1968 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1969 } 1970 1971 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1972 family); 1973 if (n) 1974 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1975 1976 return true; 1977 } 1978 1979 static struct xfrm_pol_inexact_bin * 1980 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1981 u8 dir, u32 if_id) 1982 { 1983 struct xfrm_pol_inexact_key k = { 1984 .family = family, 1985 .type = type, 1986 .dir = dir, 1987 .if_id = if_id, 1988 }; 1989 1990 write_pnet(&k.net, net); 1991 1992 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1993 xfrm_pol_inexact_params); 1994 } 1995 1996 static struct xfrm_pol_inexact_bin * 1997 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 1998 u8 dir, u32 if_id) 1999 { 2000 struct xfrm_pol_inexact_bin *bin; 2001 2002 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2003 2004 rcu_read_lock(); 2005 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2006 rcu_read_unlock(); 2007 2008 return bin; 2009 } 2010 2011 static struct xfrm_policy * 2012 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2013 struct xfrm_policy *prefer, 2014 const struct flowi *fl, 2015 u8 type, u16 family, int dir, u32 if_id) 2016 { 2017 u32 priority = prefer ? prefer->priority : ~0u; 2018 struct xfrm_policy *pol; 2019 2020 if (!chain) 2021 return NULL; 2022 2023 hlist_for_each_entry_rcu(pol, chain, bydst) { 2024 int err; 2025 2026 if (pol->priority > priority) 2027 break; 2028 2029 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2030 if (err) { 2031 if (err != -ESRCH) 2032 return ERR_PTR(err); 2033 2034 continue; 2035 } 2036 2037 if (prefer) { 2038 /* matches. Is it older than *prefer? */ 2039 if (pol->priority == priority && 2040 prefer->pos < pol->pos) 2041 return prefer; 2042 } 2043 2044 return pol; 2045 } 2046 2047 return NULL; 2048 } 2049 2050 static struct xfrm_policy * 2051 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2052 struct xfrm_policy *prefer, 2053 const struct flowi *fl, 2054 u8 type, u16 family, int dir, u32 if_id) 2055 { 2056 struct xfrm_policy *tmp; 2057 int i; 2058 2059 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2060 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2061 prefer, 2062 fl, type, family, dir, 2063 if_id); 2064 if (!tmp) 2065 continue; 2066 2067 if (IS_ERR(tmp)) 2068 return tmp; 2069 prefer = tmp; 2070 } 2071 2072 return prefer; 2073 } 2074 2075 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2076 const struct flowi *fl, 2077 u16 family, u8 dir, 2078 u32 if_id) 2079 { 2080 struct xfrm_pol_inexact_candidates cand; 2081 const xfrm_address_t *daddr, *saddr; 2082 struct xfrm_pol_inexact_bin *bin; 2083 struct xfrm_policy *pol, *ret; 2084 struct hlist_head *chain; 2085 unsigned int sequence; 2086 int err; 2087 2088 daddr = xfrm_flowi_daddr(fl, family); 2089 saddr = xfrm_flowi_saddr(fl, family); 2090 if (unlikely(!daddr || !saddr)) 2091 return NULL; 2092 2093 rcu_read_lock(); 2094 retry: 2095 do { 2096 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 2097 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2098 } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)); 2099 2100 ret = NULL; 2101 hlist_for_each_entry_rcu(pol, chain, bydst) { 2102 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2103 if (err) { 2104 if (err == -ESRCH) 2105 continue; 2106 else { 2107 ret = ERR_PTR(err); 2108 goto fail; 2109 } 2110 } else { 2111 ret = pol; 2112 break; 2113 } 2114 } 2115 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2116 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2117 daddr)) 2118 goto skip_inexact; 2119 2120 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2121 family, dir, if_id); 2122 if (pol) { 2123 ret = pol; 2124 if (IS_ERR(pol)) 2125 goto fail; 2126 } 2127 2128 skip_inexact: 2129 if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)) 2130 goto retry; 2131 2132 if (ret && !xfrm_pol_hold_rcu(ret)) 2133 goto retry; 2134 fail: 2135 rcu_read_unlock(); 2136 2137 return ret; 2138 } 2139 2140 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2141 const struct flowi *fl, 2142 u16 family, u8 dir, u32 if_id) 2143 { 2144 #ifdef CONFIG_XFRM_SUB_POLICY 2145 struct xfrm_policy *pol; 2146 2147 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2148 dir, if_id); 2149 if (pol != NULL) 2150 return pol; 2151 #endif 2152 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2153 dir, if_id); 2154 } 2155 2156 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2157 const struct flowi *fl, 2158 u16 family, u32 if_id) 2159 { 2160 struct xfrm_policy *pol; 2161 2162 rcu_read_lock(); 2163 again: 2164 pol = rcu_dereference(sk->sk_policy[dir]); 2165 if (pol != NULL) { 2166 bool match; 2167 int err = 0; 2168 2169 if (pol->family != family) { 2170 pol = NULL; 2171 goto out; 2172 } 2173 2174 match = xfrm_selector_match(&pol->selector, fl, family); 2175 if (match) { 2176 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2177 pol->if_id != if_id) { 2178 pol = NULL; 2179 goto out; 2180 } 2181 err = security_xfrm_policy_lookup(pol->security, 2182 fl->flowi_secid); 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 __u32 skb_mark; 2762 2763 spin_lock(&pq->hold_queue.lock); 2764 skb = skb_peek(&pq->hold_queue); 2765 if (!skb) { 2766 spin_unlock(&pq->hold_queue.lock); 2767 goto out; 2768 } 2769 dst = skb_dst(skb); 2770 sk = skb->sk; 2771 2772 /* Fixup the mark to support VTI. */ 2773 skb_mark = skb->mark; 2774 skb->mark = pol->mark.v; 2775 xfrm_decode_session(skb, &fl, dst->ops->family); 2776 skb->mark = skb_mark; 2777 spin_unlock(&pq->hold_queue.lock); 2778 2779 dst_hold(xfrm_dst_path(dst)); 2780 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2781 if (IS_ERR(dst)) 2782 goto purge_queue; 2783 2784 if (dst->flags & DST_XFRM_QUEUE) { 2785 dst_release(dst); 2786 2787 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2788 goto purge_queue; 2789 2790 pq->timeout = pq->timeout << 1; 2791 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2792 xfrm_pol_hold(pol); 2793 goto out; 2794 } 2795 2796 dst_release(dst); 2797 2798 __skb_queue_head_init(&list); 2799 2800 spin_lock(&pq->hold_queue.lock); 2801 pq->timeout = 0; 2802 skb_queue_splice_init(&pq->hold_queue, &list); 2803 spin_unlock(&pq->hold_queue.lock); 2804 2805 while (!skb_queue_empty(&list)) { 2806 skb = __skb_dequeue(&list); 2807 2808 /* Fixup the mark to support VTI. */ 2809 skb_mark = skb->mark; 2810 skb->mark = pol->mark.v; 2811 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2812 skb->mark = skb_mark; 2813 2814 dst_hold(xfrm_dst_path(skb_dst(skb))); 2815 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2816 if (IS_ERR(dst)) { 2817 kfree_skb(skb); 2818 continue; 2819 } 2820 2821 nf_reset_ct(skb); 2822 skb_dst_drop(skb); 2823 skb_dst_set(skb, dst); 2824 2825 dst_output(net, skb->sk, skb); 2826 } 2827 2828 out: 2829 xfrm_pol_put(pol); 2830 return; 2831 2832 purge_queue: 2833 pq->timeout = 0; 2834 skb_queue_purge(&pq->hold_queue); 2835 xfrm_pol_put(pol); 2836 } 2837 2838 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2839 { 2840 unsigned long sched_next; 2841 struct dst_entry *dst = skb_dst(skb); 2842 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2843 struct xfrm_policy *pol = xdst->pols[0]; 2844 struct xfrm_policy_queue *pq = &pol->polq; 2845 2846 if (unlikely(skb_fclone_busy(sk, skb))) { 2847 kfree_skb(skb); 2848 return 0; 2849 } 2850 2851 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2852 kfree_skb(skb); 2853 return -EAGAIN; 2854 } 2855 2856 skb_dst_force(skb); 2857 2858 spin_lock_bh(&pq->hold_queue.lock); 2859 2860 if (!pq->timeout) 2861 pq->timeout = XFRM_QUEUE_TMO_MIN; 2862 2863 sched_next = jiffies + pq->timeout; 2864 2865 if (del_timer(&pq->hold_timer)) { 2866 if (time_before(pq->hold_timer.expires, sched_next)) 2867 sched_next = pq->hold_timer.expires; 2868 xfrm_pol_put(pol); 2869 } 2870 2871 __skb_queue_tail(&pq->hold_queue, skb); 2872 if (!mod_timer(&pq->hold_timer, sched_next)) 2873 xfrm_pol_hold(pol); 2874 2875 spin_unlock_bh(&pq->hold_queue.lock); 2876 2877 return 0; 2878 } 2879 2880 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2881 struct xfrm_flo *xflo, 2882 const struct flowi *fl, 2883 int num_xfrms, 2884 u16 family) 2885 { 2886 int err; 2887 struct net_device *dev; 2888 struct dst_entry *dst; 2889 struct dst_entry *dst1; 2890 struct xfrm_dst *xdst; 2891 2892 xdst = xfrm_alloc_dst(net, family); 2893 if (IS_ERR(xdst)) 2894 return xdst; 2895 2896 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2897 net->xfrm.sysctl_larval_drop || 2898 num_xfrms <= 0) 2899 return xdst; 2900 2901 dst = xflo->dst_orig; 2902 dst1 = &xdst->u.dst; 2903 dst_hold(dst); 2904 xdst->route = dst; 2905 2906 dst_copy_metrics(dst1, dst); 2907 2908 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2909 dst1->flags |= DST_XFRM_QUEUE; 2910 dst1->lastuse = jiffies; 2911 2912 dst1->input = dst_discard; 2913 dst1->output = xdst_queue_output; 2914 2915 dst_hold(dst); 2916 xfrm_dst_set_child(xdst, dst); 2917 xdst->path = dst; 2918 2919 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2920 2921 err = -ENODEV; 2922 dev = dst->dev; 2923 if (!dev) 2924 goto free_dst; 2925 2926 err = xfrm_fill_dst(xdst, dev, fl); 2927 if (err) 2928 goto free_dst; 2929 2930 out: 2931 return xdst; 2932 2933 free_dst: 2934 dst_release(dst1); 2935 xdst = ERR_PTR(err); 2936 goto out; 2937 } 2938 2939 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2940 const struct flowi *fl, 2941 u16 family, u8 dir, 2942 struct xfrm_flo *xflo, u32 if_id) 2943 { 2944 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2945 int num_pols = 0, num_xfrms = 0, err; 2946 struct xfrm_dst *xdst; 2947 2948 /* Resolve policies to use if we couldn't get them from 2949 * previous cache entry */ 2950 num_pols = 1; 2951 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2952 err = xfrm_expand_policies(fl, family, pols, 2953 &num_pols, &num_xfrms); 2954 if (err < 0) 2955 goto inc_error; 2956 if (num_pols == 0) 2957 return NULL; 2958 if (num_xfrms <= 0) 2959 goto make_dummy_bundle; 2960 2961 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2962 xflo->dst_orig); 2963 if (IS_ERR(xdst)) { 2964 err = PTR_ERR(xdst); 2965 if (err == -EREMOTE) { 2966 xfrm_pols_put(pols, num_pols); 2967 return NULL; 2968 } 2969 2970 if (err != -EAGAIN) 2971 goto error; 2972 goto make_dummy_bundle; 2973 } else if (xdst == NULL) { 2974 num_xfrms = 0; 2975 goto make_dummy_bundle; 2976 } 2977 2978 return xdst; 2979 2980 make_dummy_bundle: 2981 /* We found policies, but there's no bundles to instantiate: 2982 * either because the policy blocks, has no transformations or 2983 * we could not build template (no xfrm_states).*/ 2984 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2985 if (IS_ERR(xdst)) { 2986 xfrm_pols_put(pols, num_pols); 2987 return ERR_CAST(xdst); 2988 } 2989 xdst->num_pols = num_pols; 2990 xdst->num_xfrms = num_xfrms; 2991 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2992 2993 return xdst; 2994 2995 inc_error: 2996 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2997 error: 2998 xfrm_pols_put(pols, num_pols); 2999 return ERR_PTR(err); 3000 } 3001 3002 static struct dst_entry *make_blackhole(struct net *net, u16 family, 3003 struct dst_entry *dst_orig) 3004 { 3005 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 3006 struct dst_entry *ret; 3007 3008 if (!afinfo) { 3009 dst_release(dst_orig); 3010 return ERR_PTR(-EINVAL); 3011 } else { 3012 ret = afinfo->blackhole_route(net, dst_orig); 3013 } 3014 rcu_read_unlock(); 3015 3016 return ret; 3017 } 3018 3019 /* Finds/creates a bundle for given flow and if_id 3020 * 3021 * At the moment we eat a raw IP route. Mostly to speed up lookups 3022 * on interfaces with disabled IPsec. 3023 * 3024 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3025 * compatibility 3026 */ 3027 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3028 struct dst_entry *dst_orig, 3029 const struct flowi *fl, 3030 const struct sock *sk, 3031 int flags, u32 if_id) 3032 { 3033 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3034 struct xfrm_dst *xdst; 3035 struct dst_entry *dst, *route; 3036 u16 family = dst_orig->ops->family; 3037 u8 dir = XFRM_POLICY_OUT; 3038 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3039 3040 dst = NULL; 3041 xdst = NULL; 3042 route = NULL; 3043 3044 sk = sk_const_to_full_sk(sk); 3045 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3046 num_pols = 1; 3047 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3048 if_id); 3049 err = xfrm_expand_policies(fl, family, pols, 3050 &num_pols, &num_xfrms); 3051 if (err < 0) 3052 goto dropdst; 3053 3054 if (num_pols) { 3055 if (num_xfrms <= 0) { 3056 drop_pols = num_pols; 3057 goto no_transform; 3058 } 3059 3060 xdst = xfrm_resolve_and_create_bundle( 3061 pols, num_pols, fl, 3062 family, dst_orig); 3063 3064 if (IS_ERR(xdst)) { 3065 xfrm_pols_put(pols, num_pols); 3066 err = PTR_ERR(xdst); 3067 if (err == -EREMOTE) 3068 goto nopol; 3069 3070 goto dropdst; 3071 } else if (xdst == NULL) { 3072 num_xfrms = 0; 3073 drop_pols = num_pols; 3074 goto no_transform; 3075 } 3076 3077 route = xdst->route; 3078 } 3079 } 3080 3081 if (xdst == NULL) { 3082 struct xfrm_flo xflo; 3083 3084 xflo.dst_orig = dst_orig; 3085 xflo.flags = flags; 3086 3087 /* To accelerate a bit... */ 3088 if (!if_id && ((dst_orig->flags & DST_NOXFRM) || 3089 !net->xfrm.policy_count[XFRM_POLICY_OUT])) 3090 goto nopol; 3091 3092 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3093 if (xdst == NULL) 3094 goto nopol; 3095 if (IS_ERR(xdst)) { 3096 err = PTR_ERR(xdst); 3097 goto dropdst; 3098 } 3099 3100 num_pols = xdst->num_pols; 3101 num_xfrms = xdst->num_xfrms; 3102 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3103 route = xdst->route; 3104 } 3105 3106 dst = &xdst->u.dst; 3107 if (route == NULL && num_xfrms > 0) { 3108 /* The only case when xfrm_bundle_lookup() returns a 3109 * bundle with null route, is when the template could 3110 * not be resolved. It means policies are there, but 3111 * bundle could not be created, since we don't yet 3112 * have the xfrm_state's. We need to wait for KM to 3113 * negotiate new SA's or bail out with error.*/ 3114 if (net->xfrm.sysctl_larval_drop) { 3115 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3116 err = -EREMOTE; 3117 goto error; 3118 } 3119 3120 err = -EAGAIN; 3121 3122 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3123 goto error; 3124 } 3125 3126 no_transform: 3127 if (num_pols == 0) 3128 goto nopol; 3129 3130 if ((flags & XFRM_LOOKUP_ICMP) && 3131 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3132 err = -ENOENT; 3133 goto error; 3134 } 3135 3136 for (i = 0; i < num_pols; i++) 3137 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3138 3139 if (num_xfrms < 0) { 3140 /* Prohibit the flow */ 3141 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3142 err = -EPERM; 3143 goto error; 3144 } else if (num_xfrms > 0) { 3145 /* Flow transformed */ 3146 dst_release(dst_orig); 3147 } else { 3148 /* Flow passes untransformed */ 3149 dst_release(dst); 3150 dst = dst_orig; 3151 } 3152 ok: 3153 xfrm_pols_put(pols, drop_pols); 3154 if (dst && dst->xfrm && 3155 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3156 dst->flags |= DST_XFRM_TUNNEL; 3157 return dst; 3158 3159 nopol: 3160 if (!(dst_orig->dev->flags & IFF_LOOPBACK) && 3161 !xfrm_default_allow(net, dir)) { 3162 err = -EPERM; 3163 goto error; 3164 } 3165 if (!(flags & XFRM_LOOKUP_ICMP)) { 3166 dst = dst_orig; 3167 goto ok; 3168 } 3169 err = -ENOENT; 3170 error: 3171 dst_release(dst); 3172 dropdst: 3173 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3174 dst_release(dst_orig); 3175 xfrm_pols_put(pols, drop_pols); 3176 return ERR_PTR(err); 3177 } 3178 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3179 3180 /* Main function: finds/creates a bundle for given flow. 3181 * 3182 * At the moment we eat a raw IP route. Mostly to speed up lookups 3183 * on interfaces with disabled IPsec. 3184 */ 3185 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3186 const struct flowi *fl, const struct sock *sk, 3187 int flags) 3188 { 3189 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3190 } 3191 EXPORT_SYMBOL(xfrm_lookup); 3192 3193 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3194 * Otherwise we may send out blackholed packets. 3195 */ 3196 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3197 const struct flowi *fl, 3198 const struct sock *sk, int flags) 3199 { 3200 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3201 flags | XFRM_LOOKUP_QUEUE | 3202 XFRM_LOOKUP_KEEP_DST_REF); 3203 3204 if (PTR_ERR(dst) == -EREMOTE) 3205 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3206 3207 if (IS_ERR(dst)) 3208 dst_release(dst_orig); 3209 3210 return dst; 3211 } 3212 EXPORT_SYMBOL(xfrm_lookup_route); 3213 3214 static inline int 3215 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3216 { 3217 struct sec_path *sp = skb_sec_path(skb); 3218 struct xfrm_state *x; 3219 3220 if (!sp || idx < 0 || idx >= sp->len) 3221 return 0; 3222 x = sp->xvec[idx]; 3223 if (!x->type->reject) 3224 return 0; 3225 return x->type->reject(x, skb, fl); 3226 } 3227 3228 /* When skb is transformed back to its "native" form, we have to 3229 * check policy restrictions. At the moment we make this in maximally 3230 * stupid way. Shame on me. :-) Of course, connected sockets must 3231 * have policy cached at them. 3232 */ 3233 3234 static inline int 3235 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3236 unsigned short family) 3237 { 3238 if (xfrm_state_kern(x)) 3239 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3240 return x->id.proto == tmpl->id.proto && 3241 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3242 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3243 x->props.mode == tmpl->mode && 3244 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3245 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3246 !(x->props.mode != XFRM_MODE_TRANSPORT && 3247 xfrm_state_addr_cmp(tmpl, x, family)); 3248 } 3249 3250 /* 3251 * 0 or more than 0 is returned when validation is succeeded (either bypass 3252 * because of optional transport mode, or next index of the matched secpath 3253 * state with the template. 3254 * -1 is returned when no matching template is found. 3255 * Otherwise "-2 - errored_index" is returned. 3256 */ 3257 static inline int 3258 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3259 unsigned short family) 3260 { 3261 int idx = start; 3262 3263 if (tmpl->optional) { 3264 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3265 return start; 3266 } else 3267 start = -1; 3268 for (; idx < sp->len; idx++) { 3269 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3270 return ++idx; 3271 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3272 if (start == -1) 3273 start = -2-idx; 3274 break; 3275 } 3276 } 3277 return start; 3278 } 3279 3280 static void 3281 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3282 { 3283 const struct iphdr *iph = ip_hdr(skb); 3284 int ihl = iph->ihl; 3285 u8 *xprth = skb_network_header(skb) + ihl * 4; 3286 struct flowi4 *fl4 = &fl->u.ip4; 3287 int oif = 0; 3288 3289 if (skb_dst(skb) && skb_dst(skb)->dev) 3290 oif = skb_dst(skb)->dev->ifindex; 3291 3292 memset(fl4, 0, sizeof(struct flowi4)); 3293 fl4->flowi4_mark = skb->mark; 3294 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3295 3296 fl4->flowi4_proto = iph->protocol; 3297 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3298 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3299 fl4->flowi4_tos = iph->tos; 3300 3301 if (!ip_is_fragment(iph)) { 3302 switch (iph->protocol) { 3303 case IPPROTO_UDP: 3304 case IPPROTO_UDPLITE: 3305 case IPPROTO_TCP: 3306 case IPPROTO_SCTP: 3307 case IPPROTO_DCCP: 3308 if (xprth + 4 < skb->data || 3309 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3310 __be16 *ports; 3311 3312 xprth = skb_network_header(skb) + ihl * 4; 3313 ports = (__be16 *)xprth; 3314 3315 fl4->fl4_sport = ports[!!reverse]; 3316 fl4->fl4_dport = ports[!reverse]; 3317 } 3318 break; 3319 case IPPROTO_ICMP: 3320 if (xprth + 2 < skb->data || 3321 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3322 u8 *icmp; 3323 3324 xprth = skb_network_header(skb) + ihl * 4; 3325 icmp = xprth; 3326 3327 fl4->fl4_icmp_type = icmp[0]; 3328 fl4->fl4_icmp_code = icmp[1]; 3329 } 3330 break; 3331 case IPPROTO_GRE: 3332 if (xprth + 12 < skb->data || 3333 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3334 __be16 *greflags; 3335 __be32 *gre_hdr; 3336 3337 xprth = skb_network_header(skb) + ihl * 4; 3338 greflags = (__be16 *)xprth; 3339 gre_hdr = (__be32 *)xprth; 3340 3341 if (greflags[0] & GRE_KEY) { 3342 if (greflags[0] & GRE_CSUM) 3343 gre_hdr++; 3344 fl4->fl4_gre_key = gre_hdr[1]; 3345 } 3346 } 3347 break; 3348 default: 3349 break; 3350 } 3351 } 3352 } 3353 3354 #if IS_ENABLED(CONFIG_IPV6) 3355 static void 3356 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3357 { 3358 struct flowi6 *fl6 = &fl->u.ip6; 3359 int onlyproto = 0; 3360 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3361 u32 offset = sizeof(*hdr); 3362 struct ipv6_opt_hdr *exthdr; 3363 const unsigned char *nh = skb_network_header(skb); 3364 u16 nhoff = IP6CB(skb)->nhoff; 3365 int oif = 0; 3366 u8 nexthdr; 3367 3368 if (!nhoff) 3369 nhoff = offsetof(struct ipv6hdr, nexthdr); 3370 3371 nexthdr = nh[nhoff]; 3372 3373 if (skb_dst(skb) && skb_dst(skb)->dev) 3374 oif = skb_dst(skb)->dev->ifindex; 3375 3376 memset(fl6, 0, sizeof(struct flowi6)); 3377 fl6->flowi6_mark = skb->mark; 3378 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3379 3380 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3381 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3382 3383 while (nh + offset + sizeof(*exthdr) < skb->data || 3384 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3385 nh = skb_network_header(skb); 3386 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3387 3388 switch (nexthdr) { 3389 case NEXTHDR_FRAGMENT: 3390 onlyproto = 1; 3391 fallthrough; 3392 case NEXTHDR_ROUTING: 3393 case NEXTHDR_HOP: 3394 case NEXTHDR_DEST: 3395 offset += ipv6_optlen(exthdr); 3396 nexthdr = exthdr->nexthdr; 3397 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3398 break; 3399 case IPPROTO_UDP: 3400 case IPPROTO_UDPLITE: 3401 case IPPROTO_TCP: 3402 case IPPROTO_SCTP: 3403 case IPPROTO_DCCP: 3404 if (!onlyproto && (nh + offset + 4 < skb->data || 3405 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3406 __be16 *ports; 3407 3408 nh = skb_network_header(skb); 3409 ports = (__be16 *)(nh + offset); 3410 fl6->fl6_sport = ports[!!reverse]; 3411 fl6->fl6_dport = ports[!reverse]; 3412 } 3413 fl6->flowi6_proto = nexthdr; 3414 return; 3415 case IPPROTO_ICMPV6: 3416 if (!onlyproto && (nh + offset + 2 < skb->data || 3417 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3418 u8 *icmp; 3419 3420 nh = skb_network_header(skb); 3421 icmp = (u8 *)(nh + offset); 3422 fl6->fl6_icmp_type = icmp[0]; 3423 fl6->fl6_icmp_code = icmp[1]; 3424 } 3425 fl6->flowi6_proto = nexthdr; 3426 return; 3427 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3428 case IPPROTO_MH: 3429 offset += ipv6_optlen(exthdr); 3430 if (!onlyproto && (nh + offset + 3 < skb->data || 3431 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3432 struct ip6_mh *mh; 3433 3434 nh = skb_network_header(skb); 3435 mh = (struct ip6_mh *)(nh + offset); 3436 fl6->fl6_mh_type = mh->ip6mh_type; 3437 } 3438 fl6->flowi6_proto = nexthdr; 3439 return; 3440 #endif 3441 default: 3442 fl6->flowi6_proto = nexthdr; 3443 return; 3444 } 3445 } 3446 } 3447 #endif 3448 3449 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3450 unsigned int family, int reverse) 3451 { 3452 switch (family) { 3453 case AF_INET: 3454 decode_session4(skb, fl, reverse); 3455 break; 3456 #if IS_ENABLED(CONFIG_IPV6) 3457 case AF_INET6: 3458 decode_session6(skb, fl, reverse); 3459 break; 3460 #endif 3461 default: 3462 return -EAFNOSUPPORT; 3463 } 3464 3465 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3466 } 3467 EXPORT_SYMBOL(__xfrm_decode_session); 3468 3469 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3470 { 3471 for (; k < sp->len; k++) { 3472 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3473 *idxp = k; 3474 return 1; 3475 } 3476 } 3477 3478 return 0; 3479 } 3480 3481 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3482 unsigned short family) 3483 { 3484 struct net *net = dev_net(skb->dev); 3485 struct xfrm_policy *pol; 3486 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3487 int npols = 0; 3488 int xfrm_nr; 3489 int pi; 3490 int reverse; 3491 struct flowi fl; 3492 int xerr_idx = -1; 3493 const struct xfrm_if_cb *ifcb; 3494 struct sec_path *sp; 3495 struct xfrm_if *xi; 3496 u32 if_id = 0; 3497 3498 rcu_read_lock(); 3499 ifcb = xfrm_if_get_cb(); 3500 3501 if (ifcb) { 3502 xi = ifcb->decode_session(skb, family); 3503 if (xi) { 3504 if_id = xi->p.if_id; 3505 net = xi->net; 3506 } 3507 } 3508 rcu_read_unlock(); 3509 3510 reverse = dir & ~XFRM_POLICY_MASK; 3511 dir &= XFRM_POLICY_MASK; 3512 3513 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3514 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3515 return 0; 3516 } 3517 3518 nf_nat_decode_session(skb, &fl, family); 3519 3520 /* First, check used SA against their selectors. */ 3521 sp = skb_sec_path(skb); 3522 if (sp) { 3523 int i; 3524 3525 for (i = sp->len - 1; i >= 0; i--) { 3526 struct xfrm_state *x = sp->xvec[i]; 3527 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3528 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3529 return 0; 3530 } 3531 } 3532 } 3533 3534 pol = NULL; 3535 sk = sk_to_full_sk(sk); 3536 if (sk && sk->sk_policy[dir]) { 3537 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3538 if (IS_ERR(pol)) { 3539 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3540 return 0; 3541 } 3542 } 3543 3544 if (!pol) 3545 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3546 3547 if (IS_ERR(pol)) { 3548 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3549 return 0; 3550 } 3551 3552 if (!pol) { 3553 if (!xfrm_default_allow(net, dir)) { 3554 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3555 return 0; 3556 } 3557 3558 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3559 xfrm_secpath_reject(xerr_idx, skb, &fl); 3560 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3561 return 0; 3562 } 3563 return 1; 3564 } 3565 3566 pol->curlft.use_time = ktime_get_real_seconds(); 3567 3568 pols[0] = pol; 3569 npols++; 3570 #ifdef CONFIG_XFRM_SUB_POLICY 3571 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3572 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3573 &fl, family, 3574 XFRM_POLICY_IN, if_id); 3575 if (pols[1]) { 3576 if (IS_ERR(pols[1])) { 3577 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3578 return 0; 3579 } 3580 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3581 npols++; 3582 } 3583 } 3584 #endif 3585 3586 if (pol->action == XFRM_POLICY_ALLOW) { 3587 static struct sec_path dummy; 3588 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3589 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3590 struct xfrm_tmpl **tpp = tp; 3591 int ti = 0; 3592 int i, k; 3593 3594 sp = skb_sec_path(skb); 3595 if (!sp) 3596 sp = &dummy; 3597 3598 for (pi = 0; pi < npols; pi++) { 3599 if (pols[pi] != pol && 3600 pols[pi]->action != XFRM_POLICY_ALLOW) { 3601 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3602 goto reject; 3603 } 3604 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3605 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3606 goto reject_error; 3607 } 3608 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3609 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3610 } 3611 xfrm_nr = ti; 3612 3613 if (!xfrm_default_allow(net, dir) && !xfrm_nr) { 3614 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); 3615 goto reject; 3616 } 3617 3618 if (npols > 1) { 3619 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3620 tpp = stp; 3621 } 3622 3623 /* For each tunnel xfrm, find the first matching tmpl. 3624 * For each tmpl before that, find corresponding xfrm. 3625 * Order is _important_. Later we will implement 3626 * some barriers, but at the moment barriers 3627 * are implied between each two transformations. 3628 */ 3629 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3630 k = xfrm_policy_ok(tpp[i], sp, k, family); 3631 if (k < 0) { 3632 if (k < -1) 3633 /* "-2 - errored_index" returned */ 3634 xerr_idx = -(2+k); 3635 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3636 goto reject; 3637 } 3638 } 3639 3640 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3641 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3642 goto reject; 3643 } 3644 3645 xfrm_pols_put(pols, npols); 3646 return 1; 3647 } 3648 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3649 3650 reject: 3651 xfrm_secpath_reject(xerr_idx, skb, &fl); 3652 reject_error: 3653 xfrm_pols_put(pols, npols); 3654 return 0; 3655 } 3656 EXPORT_SYMBOL(__xfrm_policy_check); 3657 3658 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3659 { 3660 struct net *net = dev_net(skb->dev); 3661 struct flowi fl; 3662 struct dst_entry *dst; 3663 int res = 1; 3664 3665 if (xfrm_decode_session(skb, &fl, family) < 0) { 3666 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3667 return 0; 3668 } 3669 3670 skb_dst_force(skb); 3671 if (!skb_dst(skb)) { 3672 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3673 return 0; 3674 } 3675 3676 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3677 if (IS_ERR(dst)) { 3678 res = 0; 3679 dst = NULL; 3680 } 3681 skb_dst_set(skb, dst); 3682 return res; 3683 } 3684 EXPORT_SYMBOL(__xfrm_route_forward); 3685 3686 /* Optimize later using cookies and generation ids. */ 3687 3688 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3689 { 3690 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3691 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3692 * get validated by dst_ops->check on every use. We do this 3693 * because when a normal route referenced by an XFRM dst is 3694 * obsoleted we do not go looking around for all parent 3695 * referencing XFRM dsts so that we can invalidate them. It 3696 * is just too much work. Instead we make the checks here on 3697 * every use. For example: 3698 * 3699 * XFRM dst A --> IPv4 dst X 3700 * 3701 * X is the "xdst->route" of A (X is also the "dst->path" of A 3702 * in this example). If X is marked obsolete, "A" will not 3703 * notice. That's what we are validating here via the 3704 * stale_bundle() check. 3705 * 3706 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3707 * be marked on it. 3708 * This will force stale_bundle() to fail on any xdst bundle with 3709 * this dst linked in it. 3710 */ 3711 if (dst->obsolete < 0 && !stale_bundle(dst)) 3712 return dst; 3713 3714 return NULL; 3715 } 3716 3717 static int stale_bundle(struct dst_entry *dst) 3718 { 3719 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3720 } 3721 3722 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3723 { 3724 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3725 dst->dev = dev_net(dev)->loopback_dev; 3726 dev_hold(dst->dev); 3727 dev_put(dev); 3728 } 3729 } 3730 EXPORT_SYMBOL(xfrm_dst_ifdown); 3731 3732 static void xfrm_link_failure(struct sk_buff *skb) 3733 { 3734 /* Impossible. Such dst must be popped before reaches point of failure. */ 3735 } 3736 3737 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3738 { 3739 if (dst) { 3740 if (dst->obsolete) { 3741 dst_release(dst); 3742 dst = NULL; 3743 } 3744 } 3745 return dst; 3746 } 3747 3748 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3749 { 3750 while (nr--) { 3751 struct xfrm_dst *xdst = bundle[nr]; 3752 u32 pmtu, route_mtu_cached; 3753 struct dst_entry *dst; 3754 3755 dst = &xdst->u.dst; 3756 pmtu = dst_mtu(xfrm_dst_child(dst)); 3757 xdst->child_mtu_cached = pmtu; 3758 3759 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3760 3761 route_mtu_cached = dst_mtu(xdst->route); 3762 xdst->route_mtu_cached = route_mtu_cached; 3763 3764 if (pmtu > route_mtu_cached) 3765 pmtu = route_mtu_cached; 3766 3767 dst_metric_set(dst, RTAX_MTU, pmtu); 3768 } 3769 } 3770 3771 /* Check that the bundle accepts the flow and its components are 3772 * still valid. 3773 */ 3774 3775 static int xfrm_bundle_ok(struct xfrm_dst *first) 3776 { 3777 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3778 struct dst_entry *dst = &first->u.dst; 3779 struct xfrm_dst *xdst; 3780 int start_from, nr; 3781 u32 mtu; 3782 3783 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3784 (dst->dev && !netif_running(dst->dev))) 3785 return 0; 3786 3787 if (dst->flags & DST_XFRM_QUEUE) 3788 return 1; 3789 3790 start_from = nr = 0; 3791 do { 3792 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3793 3794 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3795 return 0; 3796 if (xdst->xfrm_genid != dst->xfrm->genid) 3797 return 0; 3798 if (xdst->num_pols > 0 && 3799 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3800 return 0; 3801 3802 bundle[nr++] = xdst; 3803 3804 mtu = dst_mtu(xfrm_dst_child(dst)); 3805 if (xdst->child_mtu_cached != mtu) { 3806 start_from = nr; 3807 xdst->child_mtu_cached = mtu; 3808 } 3809 3810 if (!dst_check(xdst->route, xdst->route_cookie)) 3811 return 0; 3812 mtu = dst_mtu(xdst->route); 3813 if (xdst->route_mtu_cached != mtu) { 3814 start_from = nr; 3815 xdst->route_mtu_cached = mtu; 3816 } 3817 3818 dst = xfrm_dst_child(dst); 3819 } while (dst->xfrm); 3820 3821 if (likely(!start_from)) 3822 return 1; 3823 3824 xdst = bundle[start_from - 1]; 3825 mtu = xdst->child_mtu_cached; 3826 while (start_from--) { 3827 dst = &xdst->u.dst; 3828 3829 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3830 if (mtu > xdst->route_mtu_cached) 3831 mtu = xdst->route_mtu_cached; 3832 dst_metric_set(dst, RTAX_MTU, mtu); 3833 if (!start_from) 3834 break; 3835 3836 xdst = bundle[start_from - 1]; 3837 xdst->child_mtu_cached = mtu; 3838 } 3839 3840 return 1; 3841 } 3842 3843 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3844 { 3845 return dst_metric_advmss(xfrm_dst_path(dst)); 3846 } 3847 3848 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3849 { 3850 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3851 3852 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3853 } 3854 3855 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3856 const void *daddr) 3857 { 3858 while (dst->xfrm) { 3859 const struct xfrm_state *xfrm = dst->xfrm; 3860 3861 dst = xfrm_dst_child(dst); 3862 3863 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3864 continue; 3865 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3866 daddr = xfrm->coaddr; 3867 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3868 daddr = &xfrm->id.daddr; 3869 } 3870 return daddr; 3871 } 3872 3873 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3874 struct sk_buff *skb, 3875 const void *daddr) 3876 { 3877 const struct dst_entry *path = xfrm_dst_path(dst); 3878 3879 if (!skb) 3880 daddr = xfrm_get_dst_nexthop(dst, daddr); 3881 return path->ops->neigh_lookup(path, skb, daddr); 3882 } 3883 3884 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3885 { 3886 const struct dst_entry *path = xfrm_dst_path(dst); 3887 3888 daddr = xfrm_get_dst_nexthop(dst, daddr); 3889 path->ops->confirm_neigh(path, daddr); 3890 } 3891 3892 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3893 { 3894 int err = 0; 3895 3896 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3897 return -EAFNOSUPPORT; 3898 3899 spin_lock(&xfrm_policy_afinfo_lock); 3900 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3901 err = -EEXIST; 3902 else { 3903 struct dst_ops *dst_ops = afinfo->dst_ops; 3904 if (likely(dst_ops->kmem_cachep == NULL)) 3905 dst_ops->kmem_cachep = xfrm_dst_cache; 3906 if (likely(dst_ops->check == NULL)) 3907 dst_ops->check = xfrm_dst_check; 3908 if (likely(dst_ops->default_advmss == NULL)) 3909 dst_ops->default_advmss = xfrm_default_advmss; 3910 if (likely(dst_ops->mtu == NULL)) 3911 dst_ops->mtu = xfrm_mtu; 3912 if (likely(dst_ops->negative_advice == NULL)) 3913 dst_ops->negative_advice = xfrm_negative_advice; 3914 if (likely(dst_ops->link_failure == NULL)) 3915 dst_ops->link_failure = xfrm_link_failure; 3916 if (likely(dst_ops->neigh_lookup == NULL)) 3917 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3918 if (likely(!dst_ops->confirm_neigh)) 3919 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3920 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3921 } 3922 spin_unlock(&xfrm_policy_afinfo_lock); 3923 3924 return err; 3925 } 3926 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3927 3928 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3929 { 3930 struct dst_ops *dst_ops = afinfo->dst_ops; 3931 int i; 3932 3933 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3934 if (xfrm_policy_afinfo[i] != afinfo) 3935 continue; 3936 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3937 break; 3938 } 3939 3940 synchronize_rcu(); 3941 3942 dst_ops->kmem_cachep = NULL; 3943 dst_ops->check = NULL; 3944 dst_ops->negative_advice = NULL; 3945 dst_ops->link_failure = NULL; 3946 } 3947 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3948 3949 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3950 { 3951 spin_lock(&xfrm_if_cb_lock); 3952 rcu_assign_pointer(xfrm_if_cb, ifcb); 3953 spin_unlock(&xfrm_if_cb_lock); 3954 } 3955 EXPORT_SYMBOL(xfrm_if_register_cb); 3956 3957 void xfrm_if_unregister_cb(void) 3958 { 3959 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3960 synchronize_rcu(); 3961 } 3962 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3963 3964 #ifdef CONFIG_XFRM_STATISTICS 3965 static int __net_init xfrm_statistics_init(struct net *net) 3966 { 3967 int rv; 3968 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3969 if (!net->mib.xfrm_statistics) 3970 return -ENOMEM; 3971 rv = xfrm_proc_init(net); 3972 if (rv < 0) 3973 free_percpu(net->mib.xfrm_statistics); 3974 return rv; 3975 } 3976 3977 static void xfrm_statistics_fini(struct net *net) 3978 { 3979 xfrm_proc_fini(net); 3980 free_percpu(net->mib.xfrm_statistics); 3981 } 3982 #else 3983 static int __net_init xfrm_statistics_init(struct net *net) 3984 { 3985 return 0; 3986 } 3987 3988 static void xfrm_statistics_fini(struct net *net) 3989 { 3990 } 3991 #endif 3992 3993 static int __net_init xfrm_policy_init(struct net *net) 3994 { 3995 unsigned int hmask, sz; 3996 int dir, err; 3997 3998 if (net_eq(net, &init_net)) { 3999 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4000 sizeof(struct xfrm_dst), 4001 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4002 NULL); 4003 err = rhashtable_init(&xfrm_policy_inexact_table, 4004 &xfrm_pol_inexact_params); 4005 BUG_ON(err); 4006 } 4007 4008 hmask = 8 - 1; 4009 sz = (hmask+1) * sizeof(struct hlist_head); 4010 4011 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4012 if (!net->xfrm.policy_byidx) 4013 goto out_byidx; 4014 net->xfrm.policy_idx_hmask = hmask; 4015 4016 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4017 struct xfrm_policy_hash *htab; 4018 4019 net->xfrm.policy_count[dir] = 0; 4020 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4021 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4022 4023 htab = &net->xfrm.policy_bydst[dir]; 4024 htab->table = xfrm_hash_alloc(sz); 4025 if (!htab->table) 4026 goto out_bydst; 4027 htab->hmask = hmask; 4028 htab->dbits4 = 32; 4029 htab->sbits4 = 32; 4030 htab->dbits6 = 128; 4031 htab->sbits6 = 128; 4032 } 4033 net->xfrm.policy_hthresh.lbits4 = 32; 4034 net->xfrm.policy_hthresh.rbits4 = 32; 4035 net->xfrm.policy_hthresh.lbits6 = 128; 4036 net->xfrm.policy_hthresh.rbits6 = 128; 4037 4038 seqlock_init(&net->xfrm.policy_hthresh.lock); 4039 4040 INIT_LIST_HEAD(&net->xfrm.policy_all); 4041 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4042 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4043 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4044 return 0; 4045 4046 out_bydst: 4047 for (dir--; dir >= 0; dir--) { 4048 struct xfrm_policy_hash *htab; 4049 4050 htab = &net->xfrm.policy_bydst[dir]; 4051 xfrm_hash_free(htab->table, sz); 4052 } 4053 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4054 out_byidx: 4055 return -ENOMEM; 4056 } 4057 4058 static void xfrm_policy_fini(struct net *net) 4059 { 4060 struct xfrm_pol_inexact_bin *b, *t; 4061 unsigned int sz; 4062 int dir; 4063 4064 flush_work(&net->xfrm.policy_hash_work); 4065 #ifdef CONFIG_XFRM_SUB_POLICY 4066 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4067 #endif 4068 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4069 4070 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4071 4072 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4073 struct xfrm_policy_hash *htab; 4074 4075 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4076 4077 htab = &net->xfrm.policy_bydst[dir]; 4078 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4079 WARN_ON(!hlist_empty(htab->table)); 4080 xfrm_hash_free(htab->table, sz); 4081 } 4082 4083 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4084 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4085 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4086 4087 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4088 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4089 __xfrm_policy_inexact_prune_bin(b, true); 4090 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4091 } 4092 4093 static int __net_init xfrm_net_init(struct net *net) 4094 { 4095 int rv; 4096 4097 /* Initialize the per-net locks here */ 4098 spin_lock_init(&net->xfrm.xfrm_state_lock); 4099 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4100 seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock); 4101 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4102 4103 rv = xfrm_statistics_init(net); 4104 if (rv < 0) 4105 goto out_statistics; 4106 rv = xfrm_state_init(net); 4107 if (rv < 0) 4108 goto out_state; 4109 rv = xfrm_policy_init(net); 4110 if (rv < 0) 4111 goto out_policy; 4112 rv = xfrm_sysctl_init(net); 4113 if (rv < 0) 4114 goto out_sysctl; 4115 4116 return 0; 4117 4118 out_sysctl: 4119 xfrm_policy_fini(net); 4120 out_policy: 4121 xfrm_state_fini(net); 4122 out_state: 4123 xfrm_statistics_fini(net); 4124 out_statistics: 4125 return rv; 4126 } 4127 4128 static void __net_exit xfrm_net_exit(struct net *net) 4129 { 4130 xfrm_sysctl_fini(net); 4131 xfrm_policy_fini(net); 4132 xfrm_state_fini(net); 4133 xfrm_statistics_fini(net); 4134 } 4135 4136 static struct pernet_operations __net_initdata xfrm_net_ops = { 4137 .init = xfrm_net_init, 4138 .exit = xfrm_net_exit, 4139 }; 4140 4141 void __init xfrm_init(void) 4142 { 4143 register_pernet_subsys(&xfrm_net_ops); 4144 xfrm_dev_init(); 4145 xfrm_input_init(); 4146 4147 #ifdef CONFIG_XFRM_ESPINTCP 4148 espintcp_init(); 4149 #endif 4150 } 4151 4152 #ifdef CONFIG_AUDITSYSCALL 4153 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4154 struct audit_buffer *audit_buf) 4155 { 4156 struct xfrm_sec_ctx *ctx = xp->security; 4157 struct xfrm_selector *sel = &xp->selector; 4158 4159 if (ctx) 4160 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4161 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4162 4163 switch (sel->family) { 4164 case AF_INET: 4165 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4166 if (sel->prefixlen_s != 32) 4167 audit_log_format(audit_buf, " src_prefixlen=%d", 4168 sel->prefixlen_s); 4169 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4170 if (sel->prefixlen_d != 32) 4171 audit_log_format(audit_buf, " dst_prefixlen=%d", 4172 sel->prefixlen_d); 4173 break; 4174 case AF_INET6: 4175 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4176 if (sel->prefixlen_s != 128) 4177 audit_log_format(audit_buf, " src_prefixlen=%d", 4178 sel->prefixlen_s); 4179 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4180 if (sel->prefixlen_d != 128) 4181 audit_log_format(audit_buf, " dst_prefixlen=%d", 4182 sel->prefixlen_d); 4183 break; 4184 } 4185 } 4186 4187 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4188 { 4189 struct audit_buffer *audit_buf; 4190 4191 audit_buf = xfrm_audit_start("SPD-add"); 4192 if (audit_buf == NULL) 4193 return; 4194 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4195 audit_log_format(audit_buf, " res=%u", result); 4196 xfrm_audit_common_policyinfo(xp, audit_buf); 4197 audit_log_end(audit_buf); 4198 } 4199 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4200 4201 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4202 bool task_valid) 4203 { 4204 struct audit_buffer *audit_buf; 4205 4206 audit_buf = xfrm_audit_start("SPD-delete"); 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_delete); 4215 #endif 4216 4217 #ifdef CONFIG_XFRM_MIGRATE 4218 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4219 const struct xfrm_selector *sel_tgt) 4220 { 4221 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4222 if (sel_tgt->family == sel_cmp->family && 4223 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4224 sel_cmp->family) && 4225 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4226 sel_cmp->family) && 4227 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4228 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4229 return true; 4230 } 4231 } else { 4232 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4233 return true; 4234 } 4235 } 4236 return false; 4237 } 4238 4239 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4240 u8 dir, u8 type, struct net *net) 4241 { 4242 struct xfrm_policy *pol, *ret = NULL; 4243 struct hlist_head *chain; 4244 u32 priority = ~0U; 4245 4246 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4247 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4248 hlist_for_each_entry(pol, chain, bydst) { 4249 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4250 pol->type == type) { 4251 ret = pol; 4252 priority = ret->priority; 4253 break; 4254 } 4255 } 4256 chain = &net->xfrm.policy_inexact[dir]; 4257 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4258 if ((pol->priority >= priority) && ret) 4259 break; 4260 4261 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4262 pol->type == type) { 4263 ret = pol; 4264 break; 4265 } 4266 } 4267 4268 xfrm_pol_hold(ret); 4269 4270 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4271 4272 return ret; 4273 } 4274 4275 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4276 { 4277 int match = 0; 4278 4279 if (t->mode == m->mode && t->id.proto == m->proto && 4280 (m->reqid == 0 || t->reqid == m->reqid)) { 4281 switch (t->mode) { 4282 case XFRM_MODE_TUNNEL: 4283 case XFRM_MODE_BEET: 4284 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4285 m->old_family) && 4286 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4287 m->old_family)) { 4288 match = 1; 4289 } 4290 break; 4291 case XFRM_MODE_TRANSPORT: 4292 /* in case of transport mode, template does not store 4293 any IP addresses, hence we just compare mode and 4294 protocol */ 4295 match = 1; 4296 break; 4297 default: 4298 break; 4299 } 4300 } 4301 return match; 4302 } 4303 4304 /* update endpoint address(es) of template(s) */ 4305 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4306 struct xfrm_migrate *m, int num_migrate) 4307 { 4308 struct xfrm_migrate *mp; 4309 int i, j, n = 0; 4310 4311 write_lock_bh(&pol->lock); 4312 if (unlikely(pol->walk.dead)) { 4313 /* target policy has been deleted */ 4314 write_unlock_bh(&pol->lock); 4315 return -ENOENT; 4316 } 4317 4318 for (i = 0; i < pol->xfrm_nr; i++) { 4319 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4320 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4321 continue; 4322 n++; 4323 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4324 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4325 continue; 4326 /* update endpoints */ 4327 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4328 sizeof(pol->xfrm_vec[i].id.daddr)); 4329 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4330 sizeof(pol->xfrm_vec[i].saddr)); 4331 pol->xfrm_vec[i].encap_family = mp->new_family; 4332 /* flush bundles */ 4333 atomic_inc(&pol->genid); 4334 } 4335 } 4336 4337 write_unlock_bh(&pol->lock); 4338 4339 if (!n) 4340 return -ENODATA; 4341 4342 return 0; 4343 } 4344 4345 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4346 { 4347 int i, j; 4348 4349 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4350 return -EINVAL; 4351 4352 for (i = 0; i < num_migrate; i++) { 4353 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4354 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4355 return -EINVAL; 4356 4357 /* check if there is any duplicated entry */ 4358 for (j = i + 1; j < num_migrate; j++) { 4359 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4360 sizeof(m[i].old_daddr)) && 4361 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4362 sizeof(m[i].old_saddr)) && 4363 m[i].proto == m[j].proto && 4364 m[i].mode == m[j].mode && 4365 m[i].reqid == m[j].reqid && 4366 m[i].old_family == m[j].old_family) 4367 return -EINVAL; 4368 } 4369 } 4370 4371 return 0; 4372 } 4373 4374 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4375 struct xfrm_migrate *m, int num_migrate, 4376 struct xfrm_kmaddress *k, struct net *net, 4377 struct xfrm_encap_tmpl *encap) 4378 { 4379 int i, err, nx_cur = 0, nx_new = 0; 4380 struct xfrm_policy *pol = NULL; 4381 struct xfrm_state *x, *xc; 4382 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4383 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4384 struct xfrm_migrate *mp; 4385 4386 /* Stage 0 - sanity checks */ 4387 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4388 goto out; 4389 4390 if (dir >= XFRM_POLICY_MAX) { 4391 err = -EINVAL; 4392 goto out; 4393 } 4394 4395 /* Stage 1 - find policy */ 4396 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4397 err = -ENOENT; 4398 goto out; 4399 } 4400 4401 /* Stage 2 - find and update state(s) */ 4402 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4403 if ((x = xfrm_migrate_state_find(mp, net))) { 4404 x_cur[nx_cur] = x; 4405 nx_cur++; 4406 xc = xfrm_state_migrate(x, mp, encap); 4407 if (xc) { 4408 x_new[nx_new] = xc; 4409 nx_new++; 4410 } else { 4411 err = -ENODATA; 4412 goto restore_state; 4413 } 4414 } 4415 } 4416 4417 /* Stage 3 - update policy */ 4418 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4419 goto restore_state; 4420 4421 /* Stage 4 - delete old state(s) */ 4422 if (nx_cur) { 4423 xfrm_states_put(x_cur, nx_cur); 4424 xfrm_states_delete(x_cur, nx_cur); 4425 } 4426 4427 /* Stage 5 - announce */ 4428 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4429 4430 xfrm_pol_put(pol); 4431 4432 return 0; 4433 out: 4434 return err; 4435 4436 restore_state: 4437 if (pol) 4438 xfrm_pol_put(pol); 4439 if (nx_cur) 4440 xfrm_states_put(x_cur, nx_cur); 4441 if (nx_new) 4442 xfrm_states_delete(x_new, nx_new); 4443 4444 return err; 4445 } 4446 EXPORT_SYMBOL(xfrm_migrate); 4447 #endif 4448