1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * xfrm_policy.c 4 * 5 * Changes: 6 * Mitsuru KANDA @USAGI 7 * Kazunori MIYAZAWA @USAGI 8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 9 * IPv6 support 10 * Kazunori MIYAZAWA @USAGI 11 * YOSHIFUJI Hideaki 12 * Split up af-specific portion 13 * Derek Atkins <derek@ihtfp.com> Add the post_input processor 14 * 15 */ 16 17 #include <linux/err.h> 18 #include <linux/slab.h> 19 #include <linux/kmod.h> 20 #include <linux/list.h> 21 #include <linux/spinlock.h> 22 #include <linux/workqueue.h> 23 #include <linux/notifier.h> 24 #include <linux/netdevice.h> 25 #include <linux/netfilter.h> 26 #include <linux/module.h> 27 #include <linux/cache.h> 28 #include <linux/cpu.h> 29 #include <linux/audit.h> 30 #include <linux/rhashtable.h> 31 #include <linux/if_tunnel.h> 32 #include <net/dst.h> 33 #include <net/flow.h> 34 #include <net/xfrm.h> 35 #include <net/ip.h> 36 #if IS_ENABLED(CONFIG_IPV6_MIP6) 37 #include <net/mip6.h> 38 #endif 39 #ifdef CONFIG_XFRM_STATISTICS 40 #include <net/snmp.h> 41 #endif 42 #ifdef CONFIG_INET_ESPINTCP 43 #include <net/espintcp.h> 44 #endif 45 46 #include "xfrm_hash.h" 47 48 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 49 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 50 #define XFRM_MAX_QUEUE_LEN 100 51 52 struct xfrm_flo { 53 struct dst_entry *dst_orig; 54 u8 flags; 55 }; 56 57 /* prefixes smaller than this are stored in lists, not trees. */ 58 #define INEXACT_PREFIXLEN_IPV4 16 59 #define INEXACT_PREFIXLEN_IPV6 48 60 61 struct xfrm_pol_inexact_node { 62 struct rb_node node; 63 union { 64 xfrm_address_t addr; 65 struct rcu_head rcu; 66 }; 67 u8 prefixlen; 68 69 struct rb_root root; 70 71 /* the policies matching this node, can be empty list */ 72 struct hlist_head hhead; 73 }; 74 75 /* xfrm inexact policy search tree: 76 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id); 77 * | 78 * +---- root_d: sorted by daddr:prefix 79 * | | 80 * | xfrm_pol_inexact_node 81 * | | 82 * | +- root: sorted by saddr/prefix 83 * | | | 84 * | | xfrm_pol_inexact_node 85 * | | | 86 * | | + root: unused 87 * | | | 88 * | | + hhead: saddr:daddr policies 89 * | | 90 * | +- coarse policies and all any:daddr policies 91 * | 92 * +---- root_s: sorted by saddr:prefix 93 * | | 94 * | xfrm_pol_inexact_node 95 * | | 96 * | + root: unused 97 * | | 98 * | + hhead: saddr:any policies 99 * | 100 * +---- coarse policies and all any:any policies 101 * 102 * Lookups return four candidate lists: 103 * 1. any:any list from top-level xfrm_pol_inexact_bin 104 * 2. any:daddr list from daddr tree 105 * 3. saddr:daddr list from 2nd level daddr tree 106 * 4. saddr:any list from saddr tree 107 * 108 * This result set then needs to be searched for the policy with 109 * the lowest priority. If two results have same prio, youngest one wins. 110 */ 111 112 struct xfrm_pol_inexact_key { 113 possible_net_t net; 114 u32 if_id; 115 u16 family; 116 u8 dir, type; 117 }; 118 119 struct xfrm_pol_inexact_bin { 120 struct xfrm_pol_inexact_key k; 121 struct rhash_head head; 122 /* list containing '*:*' policies */ 123 struct hlist_head hhead; 124 125 seqcount_t count; 126 /* tree sorted by daddr/prefix */ 127 struct rb_root root_d; 128 129 /* tree sorted by saddr/prefix */ 130 struct rb_root root_s; 131 132 /* slow path below */ 133 struct list_head inexact_bins; 134 struct rcu_head rcu; 135 }; 136 137 enum xfrm_pol_inexact_candidate_type { 138 XFRM_POL_CAND_BOTH, 139 XFRM_POL_CAND_SADDR, 140 XFRM_POL_CAND_DADDR, 141 XFRM_POL_CAND_ANY, 142 143 XFRM_POL_CAND_MAX, 144 }; 145 146 struct xfrm_pol_inexact_candidates { 147 struct hlist_head *res[XFRM_POL_CAND_MAX]; 148 }; 149 150 static DEFINE_SPINLOCK(xfrm_if_cb_lock); 151 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 152 153 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 154 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 155 __read_mostly; 156 157 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 158 static __read_mostly seqcount_t xfrm_policy_hash_generation; 159 160 static struct rhashtable xfrm_policy_inexact_table; 161 static const struct rhashtable_params xfrm_pol_inexact_params; 162 163 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 164 static int stale_bundle(struct dst_entry *dst); 165 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 166 static void xfrm_policy_queue_process(struct timer_list *t); 167 168 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 169 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 170 int dir); 171 172 static struct xfrm_pol_inexact_bin * 173 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, 174 u32 if_id); 175 176 static struct xfrm_pol_inexact_bin * 177 xfrm_policy_inexact_lookup_rcu(struct net *net, 178 u8 type, u16 family, u8 dir, u32 if_id); 179 static struct xfrm_policy * 180 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, 181 bool excl); 182 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 183 struct xfrm_policy *policy); 184 185 static bool 186 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 187 struct xfrm_pol_inexact_bin *b, 188 const xfrm_address_t *saddr, 189 const xfrm_address_t *daddr); 190 191 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 192 { 193 return refcount_inc_not_zero(&policy->refcnt); 194 } 195 196 static inline bool 197 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 198 { 199 const struct flowi4 *fl4 = &fl->u.ip4; 200 201 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 202 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 203 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 204 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 205 (fl4->flowi4_proto == sel->proto || !sel->proto) && 206 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 207 } 208 209 static inline bool 210 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 211 { 212 const struct flowi6 *fl6 = &fl->u.ip6; 213 214 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 215 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 216 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 217 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 218 (fl6->flowi6_proto == sel->proto || !sel->proto) && 219 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 220 } 221 222 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 223 unsigned short family) 224 { 225 switch (family) { 226 case AF_INET: 227 return __xfrm4_selector_match(sel, fl); 228 case AF_INET6: 229 return __xfrm6_selector_match(sel, fl); 230 } 231 return false; 232 } 233 234 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 235 { 236 const struct xfrm_policy_afinfo *afinfo; 237 238 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 239 return NULL; 240 rcu_read_lock(); 241 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 242 if (unlikely(!afinfo)) 243 rcu_read_unlock(); 244 return afinfo; 245 } 246 247 /* Called with rcu_read_lock(). */ 248 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 249 { 250 return rcu_dereference(xfrm_if_cb); 251 } 252 253 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 254 const xfrm_address_t *saddr, 255 const xfrm_address_t *daddr, 256 int family, u32 mark) 257 { 258 const struct xfrm_policy_afinfo *afinfo; 259 struct dst_entry *dst; 260 261 afinfo = xfrm_policy_get_afinfo(family); 262 if (unlikely(afinfo == NULL)) 263 return ERR_PTR(-EAFNOSUPPORT); 264 265 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 266 267 rcu_read_unlock(); 268 269 return dst; 270 } 271 EXPORT_SYMBOL(__xfrm_dst_lookup); 272 273 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 274 int tos, int oif, 275 xfrm_address_t *prev_saddr, 276 xfrm_address_t *prev_daddr, 277 int family, u32 mark) 278 { 279 struct net *net = xs_net(x); 280 xfrm_address_t *saddr = &x->props.saddr; 281 xfrm_address_t *daddr = &x->id.daddr; 282 struct dst_entry *dst; 283 284 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 285 saddr = x->coaddr; 286 daddr = prev_daddr; 287 } 288 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 289 saddr = prev_saddr; 290 daddr = x->coaddr; 291 } 292 293 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 294 295 if (!IS_ERR(dst)) { 296 if (prev_saddr != saddr) 297 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 298 if (prev_daddr != daddr) 299 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 300 } 301 302 return dst; 303 } 304 305 static inline unsigned long make_jiffies(long secs) 306 { 307 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 308 return MAX_SCHEDULE_TIMEOUT-1; 309 else 310 return secs*HZ; 311 } 312 313 static void xfrm_policy_timer(struct timer_list *t) 314 { 315 struct xfrm_policy *xp = from_timer(xp, t, timer); 316 time64_t now = ktime_get_real_seconds(); 317 time64_t next = TIME64_MAX; 318 int warn = 0; 319 int dir; 320 321 read_lock(&xp->lock); 322 323 if (unlikely(xp->walk.dead)) 324 goto out; 325 326 dir = xfrm_policy_id2dir(xp->index); 327 328 if (xp->lft.hard_add_expires_seconds) { 329 time64_t tmo = xp->lft.hard_add_expires_seconds + 330 xp->curlft.add_time - now; 331 if (tmo <= 0) 332 goto expired; 333 if (tmo < next) 334 next = tmo; 335 } 336 if (xp->lft.hard_use_expires_seconds) { 337 time64_t tmo = xp->lft.hard_use_expires_seconds + 338 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 339 if (tmo <= 0) 340 goto expired; 341 if (tmo < next) 342 next = tmo; 343 } 344 if (xp->lft.soft_add_expires_seconds) { 345 time64_t tmo = xp->lft.soft_add_expires_seconds + 346 xp->curlft.add_time - now; 347 if (tmo <= 0) { 348 warn = 1; 349 tmo = XFRM_KM_TIMEOUT; 350 } 351 if (tmo < next) 352 next = tmo; 353 } 354 if (xp->lft.soft_use_expires_seconds) { 355 time64_t tmo = xp->lft.soft_use_expires_seconds + 356 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 357 if (tmo <= 0) { 358 warn = 1; 359 tmo = XFRM_KM_TIMEOUT; 360 } 361 if (tmo < next) 362 next = tmo; 363 } 364 365 if (warn) 366 km_policy_expired(xp, dir, 0, 0); 367 if (next != TIME64_MAX && 368 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 369 xfrm_pol_hold(xp); 370 371 out: 372 read_unlock(&xp->lock); 373 xfrm_pol_put(xp); 374 return; 375 376 expired: 377 read_unlock(&xp->lock); 378 if (!xfrm_policy_delete(xp, dir)) 379 km_policy_expired(xp, dir, 1, 0); 380 xfrm_pol_put(xp); 381 } 382 383 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 384 * SPD calls. 385 */ 386 387 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 388 { 389 struct xfrm_policy *policy; 390 391 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 392 393 if (policy) { 394 write_pnet(&policy->xp_net, net); 395 INIT_LIST_HEAD(&policy->walk.all); 396 INIT_HLIST_NODE(&policy->bydst_inexact_list); 397 INIT_HLIST_NODE(&policy->bydst); 398 INIT_HLIST_NODE(&policy->byidx); 399 rwlock_init(&policy->lock); 400 refcount_set(&policy->refcnt, 1); 401 skb_queue_head_init(&policy->polq.hold_queue); 402 timer_setup(&policy->timer, xfrm_policy_timer, 0); 403 timer_setup(&policy->polq.hold_timer, 404 xfrm_policy_queue_process, 0); 405 } 406 return policy; 407 } 408 EXPORT_SYMBOL(xfrm_policy_alloc); 409 410 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 411 { 412 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 413 414 security_xfrm_policy_free(policy->security); 415 kfree(policy); 416 } 417 418 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 419 420 void xfrm_policy_destroy(struct xfrm_policy *policy) 421 { 422 BUG_ON(!policy->walk.dead); 423 424 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 425 BUG(); 426 427 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 428 } 429 EXPORT_SYMBOL(xfrm_policy_destroy); 430 431 /* Rule must be locked. Release descendant resources, announce 432 * entry dead. The rule must be unlinked from lists to the moment. 433 */ 434 435 static void xfrm_policy_kill(struct xfrm_policy *policy) 436 { 437 policy->walk.dead = 1; 438 439 atomic_inc(&policy->genid); 440 441 if (del_timer(&policy->polq.hold_timer)) 442 xfrm_pol_put(policy); 443 skb_queue_purge(&policy->polq.hold_queue); 444 445 if (del_timer(&policy->timer)) 446 xfrm_pol_put(policy); 447 448 xfrm_pol_put(policy); 449 } 450 451 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 452 453 static inline unsigned int idx_hash(struct net *net, u32 index) 454 { 455 return __idx_hash(index, net->xfrm.policy_idx_hmask); 456 } 457 458 /* calculate policy hash thresholds */ 459 static void __get_hash_thresh(struct net *net, 460 unsigned short family, int dir, 461 u8 *dbits, u8 *sbits) 462 { 463 switch (family) { 464 case AF_INET: 465 *dbits = net->xfrm.policy_bydst[dir].dbits4; 466 *sbits = net->xfrm.policy_bydst[dir].sbits4; 467 break; 468 469 case AF_INET6: 470 *dbits = net->xfrm.policy_bydst[dir].dbits6; 471 *sbits = net->xfrm.policy_bydst[dir].sbits6; 472 break; 473 474 default: 475 *dbits = 0; 476 *sbits = 0; 477 } 478 } 479 480 static struct hlist_head *policy_hash_bysel(struct net *net, 481 const struct xfrm_selector *sel, 482 unsigned short family, int dir) 483 { 484 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 485 unsigned int hash; 486 u8 dbits; 487 u8 sbits; 488 489 __get_hash_thresh(net, family, dir, &dbits, &sbits); 490 hash = __sel_hash(sel, family, hmask, dbits, sbits); 491 492 if (hash == hmask + 1) 493 return NULL; 494 495 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 496 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 497 } 498 499 static struct hlist_head *policy_hash_direct(struct net *net, 500 const xfrm_address_t *daddr, 501 const xfrm_address_t *saddr, 502 unsigned short family, int dir) 503 { 504 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 505 unsigned int hash; 506 u8 dbits; 507 u8 sbits; 508 509 __get_hash_thresh(net, family, dir, &dbits, &sbits); 510 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 511 512 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 513 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 514 } 515 516 static void xfrm_dst_hash_transfer(struct net *net, 517 struct hlist_head *list, 518 struct hlist_head *ndsttable, 519 unsigned int nhashmask, 520 int dir) 521 { 522 struct hlist_node *tmp, *entry0 = NULL; 523 struct xfrm_policy *pol; 524 unsigned int h0 = 0; 525 u8 dbits; 526 u8 sbits; 527 528 redo: 529 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 530 unsigned int h; 531 532 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 533 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 534 pol->family, nhashmask, dbits, sbits); 535 if (!entry0) { 536 hlist_del_rcu(&pol->bydst); 537 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 538 h0 = h; 539 } else { 540 if (h != h0) 541 continue; 542 hlist_del_rcu(&pol->bydst); 543 hlist_add_behind_rcu(&pol->bydst, entry0); 544 } 545 entry0 = &pol->bydst; 546 } 547 if (!hlist_empty(list)) { 548 entry0 = NULL; 549 goto redo; 550 } 551 } 552 553 static void xfrm_idx_hash_transfer(struct hlist_head *list, 554 struct hlist_head *nidxtable, 555 unsigned int nhashmask) 556 { 557 struct hlist_node *tmp; 558 struct xfrm_policy *pol; 559 560 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 561 unsigned int h; 562 563 h = __idx_hash(pol->index, nhashmask); 564 hlist_add_head(&pol->byidx, nidxtable+h); 565 } 566 } 567 568 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 569 { 570 return ((old_hmask + 1) << 1) - 1; 571 } 572 573 static void xfrm_bydst_resize(struct net *net, int dir) 574 { 575 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 576 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 577 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 578 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 579 struct hlist_head *odst; 580 int i; 581 582 if (!ndst) 583 return; 584 585 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 586 write_seqcount_begin(&xfrm_policy_hash_generation); 587 588 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 589 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 590 591 for (i = hmask; i >= 0; i--) 592 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 593 594 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 595 net->xfrm.policy_bydst[dir].hmask = nhashmask; 596 597 write_seqcount_end(&xfrm_policy_hash_generation); 598 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 599 600 synchronize_rcu(); 601 602 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 603 } 604 605 static void xfrm_byidx_resize(struct net *net, int total) 606 { 607 unsigned int hmask = net->xfrm.policy_idx_hmask; 608 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 609 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 610 struct hlist_head *oidx = net->xfrm.policy_byidx; 611 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 612 int i; 613 614 if (!nidx) 615 return; 616 617 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 618 619 for (i = hmask; i >= 0; i--) 620 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 621 622 net->xfrm.policy_byidx = nidx; 623 net->xfrm.policy_idx_hmask = nhashmask; 624 625 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 626 627 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 628 } 629 630 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 631 { 632 unsigned int cnt = net->xfrm.policy_count[dir]; 633 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 634 635 if (total) 636 *total += cnt; 637 638 if ((hmask + 1) < xfrm_policy_hashmax && 639 cnt > hmask) 640 return 1; 641 642 return 0; 643 } 644 645 static inline int xfrm_byidx_should_resize(struct net *net, int total) 646 { 647 unsigned int hmask = net->xfrm.policy_idx_hmask; 648 649 if ((hmask + 1) < xfrm_policy_hashmax && 650 total > hmask) 651 return 1; 652 653 return 0; 654 } 655 656 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 657 { 658 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 659 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 660 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 661 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 662 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 663 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 664 si->spdhcnt = net->xfrm.policy_idx_hmask; 665 si->spdhmcnt = xfrm_policy_hashmax; 666 } 667 EXPORT_SYMBOL(xfrm_spd_getinfo); 668 669 static DEFINE_MUTEX(hash_resize_mutex); 670 static void xfrm_hash_resize(struct work_struct *work) 671 { 672 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 673 int dir, total; 674 675 mutex_lock(&hash_resize_mutex); 676 677 total = 0; 678 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 679 if (xfrm_bydst_should_resize(net, dir, &total)) 680 xfrm_bydst_resize(net, dir); 681 } 682 if (xfrm_byidx_should_resize(net, total)) 683 xfrm_byidx_resize(net, total); 684 685 mutex_unlock(&hash_resize_mutex); 686 } 687 688 /* Make sure *pol can be inserted into fastbin. 689 * Useful to check that later insert requests will be sucessful 690 * (provided xfrm_policy_lock is held throughout). 691 */ 692 static struct xfrm_pol_inexact_bin * 693 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) 694 { 695 struct xfrm_pol_inexact_bin *bin, *prev; 696 struct xfrm_pol_inexact_key k = { 697 .family = pol->family, 698 .type = pol->type, 699 .dir = dir, 700 .if_id = pol->if_id, 701 }; 702 struct net *net = xp_net(pol); 703 704 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 705 706 write_pnet(&k.net, net); 707 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, 708 xfrm_pol_inexact_params); 709 if (bin) 710 return bin; 711 712 bin = kzalloc(sizeof(*bin), GFP_ATOMIC); 713 if (!bin) 714 return NULL; 715 716 bin->k = k; 717 INIT_HLIST_HEAD(&bin->hhead); 718 bin->root_d = RB_ROOT; 719 bin->root_s = RB_ROOT; 720 seqcount_init(&bin->count); 721 722 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, 723 &bin->k, &bin->head, 724 xfrm_pol_inexact_params); 725 if (!prev) { 726 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); 727 return bin; 728 } 729 730 kfree(bin); 731 732 return IS_ERR(prev) ? NULL : prev; 733 } 734 735 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, 736 int family, u8 prefixlen) 737 { 738 if (xfrm_addr_any(addr, family)) 739 return true; 740 741 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) 742 return true; 743 744 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) 745 return true; 746 747 return false; 748 } 749 750 static bool 751 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) 752 { 753 const xfrm_address_t *addr; 754 bool saddr_any, daddr_any; 755 u8 prefixlen; 756 757 addr = &policy->selector.saddr; 758 prefixlen = policy->selector.prefixlen_s; 759 760 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 761 policy->family, 762 prefixlen); 763 addr = &policy->selector.daddr; 764 prefixlen = policy->selector.prefixlen_d; 765 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 766 policy->family, 767 prefixlen); 768 return saddr_any && daddr_any; 769 } 770 771 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, 772 const xfrm_address_t *addr, u8 prefixlen) 773 { 774 node->addr = *addr; 775 node->prefixlen = prefixlen; 776 } 777 778 static struct xfrm_pol_inexact_node * 779 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) 780 { 781 struct xfrm_pol_inexact_node *node; 782 783 node = kzalloc(sizeof(*node), GFP_ATOMIC); 784 if (node) 785 xfrm_pol_inexact_node_init(node, addr, prefixlen); 786 787 return node; 788 } 789 790 static int xfrm_policy_addr_delta(const xfrm_address_t *a, 791 const xfrm_address_t *b, 792 u8 prefixlen, u16 family) 793 { 794 unsigned int pdw, pbi; 795 int delta = 0; 796 797 switch (family) { 798 case AF_INET: 799 if (sizeof(long) == 4 && prefixlen == 0) 800 return ntohl(a->a4) - ntohl(b->a4); 801 return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) - 802 (ntohl(b->a4) & ((~0UL << (32 - prefixlen)))); 803 case AF_INET6: 804 pdw = prefixlen >> 5; 805 pbi = prefixlen & 0x1f; 806 807 if (pdw) { 808 delta = memcmp(a->a6, b->a6, pdw << 2); 809 if (delta) 810 return delta; 811 } 812 if (pbi) { 813 u32 mask = ~0u << (32 - pbi); 814 815 delta = (ntohl(a->a6[pdw]) & mask) - 816 (ntohl(b->a6[pdw]) & mask); 817 } 818 break; 819 default: 820 break; 821 } 822 823 return delta; 824 } 825 826 static void xfrm_policy_inexact_list_reinsert(struct net *net, 827 struct xfrm_pol_inexact_node *n, 828 u16 family) 829 { 830 unsigned int matched_s, matched_d; 831 struct xfrm_policy *policy, *p; 832 833 matched_s = 0; 834 matched_d = 0; 835 836 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 837 struct hlist_node *newpos = NULL; 838 bool matches_s, matches_d; 839 840 if (!policy->bydst_reinsert) 841 continue; 842 843 WARN_ON_ONCE(policy->family != family); 844 845 policy->bydst_reinsert = false; 846 hlist_for_each_entry(p, &n->hhead, bydst) { 847 if (policy->priority > p->priority) 848 newpos = &p->bydst; 849 else if (policy->priority == p->priority && 850 policy->pos > p->pos) 851 newpos = &p->bydst; 852 else 853 break; 854 } 855 856 if (newpos) 857 hlist_add_behind_rcu(&policy->bydst, newpos); 858 else 859 hlist_add_head_rcu(&policy->bydst, &n->hhead); 860 861 /* paranoia checks follow. 862 * Check that the reinserted policy matches at least 863 * saddr or daddr for current node prefix. 864 * 865 * Matching both is fine, matching saddr in one policy 866 * (but not daddr) and then matching only daddr in another 867 * is a bug. 868 */ 869 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 870 &n->addr, 871 n->prefixlen, 872 family) == 0; 873 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 874 &n->addr, 875 n->prefixlen, 876 family) == 0; 877 if (matches_s && matches_d) 878 continue; 879 880 WARN_ON_ONCE(!matches_s && !matches_d); 881 if (matches_s) 882 matched_s++; 883 if (matches_d) 884 matched_d++; 885 WARN_ON_ONCE(matched_s && matched_d); 886 } 887 } 888 889 static void xfrm_policy_inexact_node_reinsert(struct net *net, 890 struct xfrm_pol_inexact_node *n, 891 struct rb_root *new, 892 u16 family) 893 { 894 struct xfrm_pol_inexact_node *node; 895 struct rb_node **p, *parent; 896 897 /* we should not have another subtree here */ 898 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 899 restart: 900 parent = NULL; 901 p = &new->rb_node; 902 while (*p) { 903 u8 prefixlen; 904 int delta; 905 906 parent = *p; 907 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 908 909 prefixlen = min(node->prefixlen, n->prefixlen); 910 911 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 912 prefixlen, family); 913 if (delta < 0) { 914 p = &parent->rb_left; 915 } else if (delta > 0) { 916 p = &parent->rb_right; 917 } else { 918 bool same_prefixlen = node->prefixlen == n->prefixlen; 919 struct xfrm_policy *tmp; 920 921 hlist_for_each_entry(tmp, &n->hhead, bydst) { 922 tmp->bydst_reinsert = true; 923 hlist_del_rcu(&tmp->bydst); 924 } 925 926 node->prefixlen = prefixlen; 927 928 xfrm_policy_inexact_list_reinsert(net, node, family); 929 930 if (same_prefixlen) { 931 kfree_rcu(n, rcu); 932 return; 933 } 934 935 rb_erase(*p, new); 936 kfree_rcu(n, rcu); 937 n = node; 938 goto restart; 939 } 940 } 941 942 rb_link_node_rcu(&n->node, parent, p); 943 rb_insert_color(&n->node, new); 944 } 945 946 /* merge nodes v and n */ 947 static void xfrm_policy_inexact_node_merge(struct net *net, 948 struct xfrm_pol_inexact_node *v, 949 struct xfrm_pol_inexact_node *n, 950 u16 family) 951 { 952 struct xfrm_pol_inexact_node *node; 953 struct xfrm_policy *tmp; 954 struct rb_node *rnode; 955 956 /* To-be-merged node v has a subtree. 957 * 958 * Dismantle it and insert its nodes to n->root. 959 */ 960 while ((rnode = rb_first(&v->root)) != NULL) { 961 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 962 rb_erase(&node->node, &v->root); 963 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 964 family); 965 } 966 967 hlist_for_each_entry(tmp, &v->hhead, bydst) { 968 tmp->bydst_reinsert = true; 969 hlist_del_rcu(&tmp->bydst); 970 } 971 972 xfrm_policy_inexact_list_reinsert(net, n, family); 973 } 974 975 static struct xfrm_pol_inexact_node * 976 xfrm_policy_inexact_insert_node(struct net *net, 977 struct rb_root *root, 978 xfrm_address_t *addr, 979 u16 family, u8 prefixlen, u8 dir) 980 { 981 struct xfrm_pol_inexact_node *cached = NULL; 982 struct rb_node **p, *parent = NULL; 983 struct xfrm_pol_inexact_node *node; 984 985 p = &root->rb_node; 986 while (*p) { 987 int delta; 988 989 parent = *p; 990 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 991 992 delta = xfrm_policy_addr_delta(addr, &node->addr, 993 node->prefixlen, 994 family); 995 if (delta == 0 && prefixlen >= node->prefixlen) { 996 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 997 return node; 998 } 999 1000 if (delta < 0) 1001 p = &parent->rb_left; 1002 else 1003 p = &parent->rb_right; 1004 1005 if (prefixlen < node->prefixlen) { 1006 delta = xfrm_policy_addr_delta(addr, &node->addr, 1007 prefixlen, 1008 family); 1009 if (delta) 1010 continue; 1011 1012 /* This node is a subnet of the new prefix. It needs 1013 * to be removed and re-inserted with the smaller 1014 * prefix and all nodes that are now also covered 1015 * by the reduced prefixlen. 1016 */ 1017 rb_erase(&node->node, root); 1018 1019 if (!cached) { 1020 xfrm_pol_inexact_node_init(node, addr, 1021 prefixlen); 1022 cached = node; 1023 } else { 1024 /* This node also falls within the new 1025 * prefixlen. Merge the to-be-reinserted 1026 * node and this one. 1027 */ 1028 xfrm_policy_inexact_node_merge(net, node, 1029 cached, family); 1030 kfree_rcu(node, rcu); 1031 } 1032 1033 /* restart */ 1034 p = &root->rb_node; 1035 parent = NULL; 1036 } 1037 } 1038 1039 node = cached; 1040 if (!node) { 1041 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1042 if (!node) 1043 return NULL; 1044 } 1045 1046 rb_link_node_rcu(&node->node, parent, p); 1047 rb_insert_color(&node->node, root); 1048 1049 return node; 1050 } 1051 1052 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1053 { 1054 struct xfrm_pol_inexact_node *node; 1055 struct rb_node *rn = rb_first(r); 1056 1057 while (rn) { 1058 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1059 1060 xfrm_policy_inexact_gc_tree(&node->root, rm); 1061 rn = rb_next(rn); 1062 1063 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1064 WARN_ON_ONCE(rm); 1065 continue; 1066 } 1067 1068 rb_erase(&node->node, r); 1069 kfree_rcu(node, rcu); 1070 } 1071 } 1072 1073 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1074 { 1075 write_seqcount_begin(&b->count); 1076 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1077 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1078 write_seqcount_end(&b->count); 1079 1080 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1081 !hlist_empty(&b->hhead)) { 1082 WARN_ON_ONCE(net_exit); 1083 return; 1084 } 1085 1086 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1087 xfrm_pol_inexact_params) == 0) { 1088 list_del(&b->inexact_bins); 1089 kfree_rcu(b, rcu); 1090 } 1091 } 1092 1093 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1094 { 1095 struct net *net = read_pnet(&b->k.net); 1096 1097 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1098 __xfrm_policy_inexact_prune_bin(b, false); 1099 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1100 } 1101 1102 static void __xfrm_policy_inexact_flush(struct net *net) 1103 { 1104 struct xfrm_pol_inexact_bin *bin, *t; 1105 1106 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1107 1108 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1109 __xfrm_policy_inexact_prune_bin(bin, false); 1110 } 1111 1112 static struct hlist_head * 1113 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1114 struct xfrm_policy *policy, u8 dir) 1115 { 1116 struct xfrm_pol_inexact_node *n; 1117 struct net *net; 1118 1119 net = xp_net(policy); 1120 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1121 1122 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1123 return &bin->hhead; 1124 1125 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1126 policy->family, 1127 policy->selector.prefixlen_d)) { 1128 write_seqcount_begin(&bin->count); 1129 n = xfrm_policy_inexact_insert_node(net, 1130 &bin->root_s, 1131 &policy->selector.saddr, 1132 policy->family, 1133 policy->selector.prefixlen_s, 1134 dir); 1135 write_seqcount_end(&bin->count); 1136 if (!n) 1137 return NULL; 1138 1139 return &n->hhead; 1140 } 1141 1142 /* daddr is fixed */ 1143 write_seqcount_begin(&bin->count); 1144 n = xfrm_policy_inexact_insert_node(net, 1145 &bin->root_d, 1146 &policy->selector.daddr, 1147 policy->family, 1148 policy->selector.prefixlen_d, dir); 1149 write_seqcount_end(&bin->count); 1150 if (!n) 1151 return NULL; 1152 1153 /* saddr is wildcard */ 1154 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1155 policy->family, 1156 policy->selector.prefixlen_s)) 1157 return &n->hhead; 1158 1159 write_seqcount_begin(&bin->count); 1160 n = xfrm_policy_inexact_insert_node(net, 1161 &n->root, 1162 &policy->selector.saddr, 1163 policy->family, 1164 policy->selector.prefixlen_s, dir); 1165 write_seqcount_end(&bin->count); 1166 if (!n) 1167 return NULL; 1168 1169 return &n->hhead; 1170 } 1171 1172 static struct xfrm_policy * 1173 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1174 { 1175 struct xfrm_pol_inexact_bin *bin; 1176 struct xfrm_policy *delpol; 1177 struct hlist_head *chain; 1178 struct net *net; 1179 1180 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1181 if (!bin) 1182 return ERR_PTR(-ENOMEM); 1183 1184 net = xp_net(policy); 1185 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1186 1187 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1188 if (!chain) { 1189 __xfrm_policy_inexact_prune_bin(bin, false); 1190 return ERR_PTR(-ENOMEM); 1191 } 1192 1193 delpol = xfrm_policy_insert_list(chain, policy, excl); 1194 if (delpol && excl) { 1195 __xfrm_policy_inexact_prune_bin(bin, false); 1196 return ERR_PTR(-EEXIST); 1197 } 1198 1199 chain = &net->xfrm.policy_inexact[dir]; 1200 xfrm_policy_insert_inexact_list(chain, policy); 1201 1202 if (delpol) 1203 __xfrm_policy_inexact_prune_bin(bin, false); 1204 1205 return delpol; 1206 } 1207 1208 static void xfrm_hash_rebuild(struct work_struct *work) 1209 { 1210 struct net *net = container_of(work, struct net, 1211 xfrm.policy_hthresh.work); 1212 unsigned int hmask; 1213 struct xfrm_policy *pol; 1214 struct xfrm_policy *policy; 1215 struct hlist_head *chain; 1216 struct hlist_head *odst; 1217 struct hlist_node *newpos; 1218 int i; 1219 int dir; 1220 unsigned seq; 1221 u8 lbits4, rbits4, lbits6, rbits6; 1222 1223 mutex_lock(&hash_resize_mutex); 1224 1225 /* read selector prefixlen thresholds */ 1226 do { 1227 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1228 1229 lbits4 = net->xfrm.policy_hthresh.lbits4; 1230 rbits4 = net->xfrm.policy_hthresh.rbits4; 1231 lbits6 = net->xfrm.policy_hthresh.lbits6; 1232 rbits6 = net->xfrm.policy_hthresh.rbits6; 1233 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1234 1235 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1236 write_seqcount_begin(&xfrm_policy_hash_generation); 1237 1238 /* make sure that we can insert the indirect policies again before 1239 * we start with destructive action. 1240 */ 1241 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1242 struct xfrm_pol_inexact_bin *bin; 1243 u8 dbits, sbits; 1244 1245 dir = xfrm_policy_id2dir(policy->index); 1246 if (policy->walk.dead || dir >= XFRM_POLICY_MAX) 1247 continue; 1248 1249 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1250 if (policy->family == AF_INET) { 1251 dbits = rbits4; 1252 sbits = lbits4; 1253 } else { 1254 dbits = rbits6; 1255 sbits = lbits6; 1256 } 1257 } else { 1258 if (policy->family == AF_INET) { 1259 dbits = lbits4; 1260 sbits = rbits4; 1261 } else { 1262 dbits = lbits6; 1263 sbits = rbits6; 1264 } 1265 } 1266 1267 if (policy->selector.prefixlen_d < dbits || 1268 policy->selector.prefixlen_s < sbits) 1269 continue; 1270 1271 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1272 if (!bin) 1273 goto out_unlock; 1274 1275 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1276 goto out_unlock; 1277 } 1278 1279 /* reset the bydst and inexact table in all directions */ 1280 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1281 struct hlist_node *n; 1282 1283 hlist_for_each_entry_safe(policy, n, 1284 &net->xfrm.policy_inexact[dir], 1285 bydst_inexact_list) { 1286 hlist_del_rcu(&policy->bydst); 1287 hlist_del_init(&policy->bydst_inexact_list); 1288 } 1289 1290 hmask = net->xfrm.policy_bydst[dir].hmask; 1291 odst = net->xfrm.policy_bydst[dir].table; 1292 for (i = hmask; i >= 0; i--) { 1293 hlist_for_each_entry_safe(policy, n, odst + i, bydst) 1294 hlist_del_rcu(&policy->bydst); 1295 } 1296 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1297 /* dir out => dst = remote, src = local */ 1298 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1299 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1300 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1301 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1302 } else { 1303 /* dir in/fwd => dst = local, src = remote */ 1304 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1305 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1306 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1307 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1308 } 1309 } 1310 1311 /* re-insert all policies by order of creation */ 1312 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1313 if (policy->walk.dead) 1314 continue; 1315 dir = xfrm_policy_id2dir(policy->index); 1316 if (dir >= XFRM_POLICY_MAX) { 1317 /* skip socket policies */ 1318 continue; 1319 } 1320 newpos = NULL; 1321 chain = policy_hash_bysel(net, &policy->selector, 1322 policy->family, dir); 1323 1324 if (!chain) { 1325 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1326 1327 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1328 continue; 1329 } 1330 1331 hlist_for_each_entry(pol, chain, bydst) { 1332 if (policy->priority >= pol->priority) 1333 newpos = &pol->bydst; 1334 else 1335 break; 1336 } 1337 if (newpos) 1338 hlist_add_behind_rcu(&policy->bydst, newpos); 1339 else 1340 hlist_add_head_rcu(&policy->bydst, chain); 1341 } 1342 1343 out_unlock: 1344 __xfrm_policy_inexact_flush(net); 1345 write_seqcount_end(&xfrm_policy_hash_generation); 1346 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1347 1348 mutex_unlock(&hash_resize_mutex); 1349 } 1350 1351 void xfrm_policy_hash_rebuild(struct net *net) 1352 { 1353 schedule_work(&net->xfrm.policy_hthresh.work); 1354 } 1355 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1356 1357 /* Generate new index... KAME seems to generate them ordered by cost 1358 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1359 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1360 { 1361 static u32 idx_generator; 1362 1363 for (;;) { 1364 struct hlist_head *list; 1365 struct xfrm_policy *p; 1366 u32 idx; 1367 int found; 1368 1369 if (!index) { 1370 idx = (idx_generator | dir); 1371 idx_generator += 8; 1372 } else { 1373 idx = index; 1374 index = 0; 1375 } 1376 1377 if (idx == 0) 1378 idx = 8; 1379 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1380 found = 0; 1381 hlist_for_each_entry(p, list, byidx) { 1382 if (p->index == idx) { 1383 found = 1; 1384 break; 1385 } 1386 } 1387 if (!found) 1388 return idx; 1389 } 1390 } 1391 1392 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1393 { 1394 u32 *p1 = (u32 *) s1; 1395 u32 *p2 = (u32 *) s2; 1396 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1397 int i; 1398 1399 for (i = 0; i < len; i++) { 1400 if (p1[i] != p2[i]) 1401 return 1; 1402 } 1403 1404 return 0; 1405 } 1406 1407 static void xfrm_policy_requeue(struct xfrm_policy *old, 1408 struct xfrm_policy *new) 1409 { 1410 struct xfrm_policy_queue *pq = &old->polq; 1411 struct sk_buff_head list; 1412 1413 if (skb_queue_empty(&pq->hold_queue)) 1414 return; 1415 1416 __skb_queue_head_init(&list); 1417 1418 spin_lock_bh(&pq->hold_queue.lock); 1419 skb_queue_splice_init(&pq->hold_queue, &list); 1420 if (del_timer(&pq->hold_timer)) 1421 xfrm_pol_put(old); 1422 spin_unlock_bh(&pq->hold_queue.lock); 1423 1424 pq = &new->polq; 1425 1426 spin_lock_bh(&pq->hold_queue.lock); 1427 skb_queue_splice(&list, &pq->hold_queue); 1428 pq->timeout = XFRM_QUEUE_TMO_MIN; 1429 if (!mod_timer(&pq->hold_timer, jiffies)) 1430 xfrm_pol_hold(new); 1431 spin_unlock_bh(&pq->hold_queue.lock); 1432 } 1433 1434 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 1435 struct xfrm_policy *pol) 1436 { 1437 u32 mark = policy->mark.v & policy->mark.m; 1438 1439 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 1440 return true; 1441 1442 if ((mark & pol->mark.m) == pol->mark.v && 1443 policy->priority == pol->priority) 1444 return true; 1445 1446 return false; 1447 } 1448 1449 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1450 { 1451 const struct xfrm_pol_inexact_key *k = data; 1452 u32 a = k->type << 24 | k->dir << 16 | k->family; 1453 1454 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1455 seed); 1456 } 1457 1458 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1459 { 1460 const struct xfrm_pol_inexact_bin *b = data; 1461 1462 return xfrm_pol_bin_key(&b->k, 0, seed); 1463 } 1464 1465 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1466 const void *ptr) 1467 { 1468 const struct xfrm_pol_inexact_key *key = arg->key; 1469 const struct xfrm_pol_inexact_bin *b = ptr; 1470 int ret; 1471 1472 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1473 return -1; 1474 1475 ret = b->k.dir ^ key->dir; 1476 if (ret) 1477 return ret; 1478 1479 ret = b->k.type ^ key->type; 1480 if (ret) 1481 return ret; 1482 1483 ret = b->k.family ^ key->family; 1484 if (ret) 1485 return ret; 1486 1487 return b->k.if_id ^ key->if_id; 1488 } 1489 1490 static const struct rhashtable_params xfrm_pol_inexact_params = { 1491 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1492 .hashfn = xfrm_pol_bin_key, 1493 .obj_hashfn = xfrm_pol_bin_obj, 1494 .obj_cmpfn = xfrm_pol_bin_cmp, 1495 .automatic_shrinking = true, 1496 }; 1497 1498 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1499 struct xfrm_policy *policy) 1500 { 1501 struct xfrm_policy *pol, *delpol = NULL; 1502 struct hlist_node *newpos = NULL; 1503 int i = 0; 1504 1505 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1506 if (pol->type == policy->type && 1507 pol->if_id == policy->if_id && 1508 !selector_cmp(&pol->selector, &policy->selector) && 1509 xfrm_policy_mark_match(policy, pol) && 1510 xfrm_sec_ctx_match(pol->security, policy->security) && 1511 !WARN_ON(delpol)) { 1512 delpol = pol; 1513 if (policy->priority > pol->priority) 1514 continue; 1515 } else if (policy->priority >= pol->priority) { 1516 newpos = &pol->bydst_inexact_list; 1517 continue; 1518 } 1519 if (delpol) 1520 break; 1521 } 1522 1523 if (newpos) 1524 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1525 else 1526 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1527 1528 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1529 pol->pos = i; 1530 i++; 1531 } 1532 } 1533 1534 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1535 struct xfrm_policy *policy, 1536 bool excl) 1537 { 1538 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1539 1540 hlist_for_each_entry(pol, chain, bydst) { 1541 if (pol->type == policy->type && 1542 pol->if_id == policy->if_id && 1543 !selector_cmp(&pol->selector, &policy->selector) && 1544 xfrm_policy_mark_match(policy, pol) && 1545 xfrm_sec_ctx_match(pol->security, policy->security) && 1546 !WARN_ON(delpol)) { 1547 if (excl) 1548 return ERR_PTR(-EEXIST); 1549 delpol = pol; 1550 if (policy->priority > pol->priority) 1551 continue; 1552 } else if (policy->priority >= pol->priority) { 1553 newpos = pol; 1554 continue; 1555 } 1556 if (delpol) 1557 break; 1558 } 1559 1560 if (newpos) 1561 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1562 else 1563 hlist_add_head_rcu(&policy->bydst, chain); 1564 1565 return delpol; 1566 } 1567 1568 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1569 { 1570 struct net *net = xp_net(policy); 1571 struct xfrm_policy *delpol; 1572 struct hlist_head *chain; 1573 1574 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1575 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1576 if (chain) 1577 delpol = xfrm_policy_insert_list(chain, policy, excl); 1578 else 1579 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1580 1581 if (IS_ERR(delpol)) { 1582 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1583 return PTR_ERR(delpol); 1584 } 1585 1586 __xfrm_policy_link(policy, dir); 1587 1588 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1589 if (policy->family == AF_INET) 1590 rt_genid_bump_ipv4(net); 1591 else 1592 rt_genid_bump_ipv6(net); 1593 1594 if (delpol) { 1595 xfrm_policy_requeue(delpol, policy); 1596 __xfrm_policy_unlink(delpol, dir); 1597 } 1598 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1599 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1600 policy->curlft.add_time = ktime_get_real_seconds(); 1601 policy->curlft.use_time = 0; 1602 if (!mod_timer(&policy->timer, jiffies + HZ)) 1603 xfrm_pol_hold(policy); 1604 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1605 1606 if (delpol) 1607 xfrm_policy_kill(delpol); 1608 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1609 schedule_work(&net->xfrm.policy_hash_work); 1610 1611 return 0; 1612 } 1613 EXPORT_SYMBOL(xfrm_policy_insert); 1614 1615 static struct xfrm_policy * 1616 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id, 1617 u8 type, int dir, 1618 struct xfrm_selector *sel, 1619 struct xfrm_sec_ctx *ctx) 1620 { 1621 struct xfrm_policy *pol; 1622 1623 if (!chain) 1624 return NULL; 1625 1626 hlist_for_each_entry(pol, chain, bydst) { 1627 if (pol->type == type && 1628 pol->if_id == if_id && 1629 (mark & pol->mark.m) == pol->mark.v && 1630 !selector_cmp(sel, &pol->selector) && 1631 xfrm_sec_ctx_match(ctx, pol->security)) 1632 return pol; 1633 } 1634 1635 return NULL; 1636 } 1637 1638 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id, 1639 u8 type, int dir, 1640 struct xfrm_selector *sel, 1641 struct xfrm_sec_ctx *ctx, int delete, 1642 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 *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id, 1710 u8 type, int dir, u32 id, int delete, 1711 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 && 1727 (mark & pol->mark.m) == pol->mark.v) { 1728 xfrm_pol_hold(pol); 1729 if (delete) { 1730 *err = security_xfrm_policy_delete( 1731 pol->security); 1732 if (*err) { 1733 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1734 return pol; 1735 } 1736 __xfrm_policy_unlink(pol, dir); 1737 } 1738 ret = pol; 1739 break; 1740 } 1741 } 1742 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1743 1744 if (ret && delete) 1745 xfrm_policy_kill(ret); 1746 return ret; 1747 } 1748 EXPORT_SYMBOL(xfrm_policy_byid); 1749 1750 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1751 static inline int 1752 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1753 { 1754 struct xfrm_policy *pol; 1755 int err = 0; 1756 1757 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1758 if (pol->walk.dead || 1759 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1760 pol->type != type) 1761 continue; 1762 1763 err = security_xfrm_policy_delete(pol->security); 1764 if (err) { 1765 xfrm_audit_policy_delete(pol, 0, task_valid); 1766 return err; 1767 } 1768 } 1769 return err; 1770 } 1771 #else 1772 static inline int 1773 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1774 { 1775 return 0; 1776 } 1777 #endif 1778 1779 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1780 { 1781 int dir, err = 0, cnt = 0; 1782 struct xfrm_policy *pol; 1783 1784 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1785 1786 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1787 if (err) 1788 goto out; 1789 1790 again: 1791 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1792 dir = xfrm_policy_id2dir(pol->index); 1793 if (pol->walk.dead || 1794 dir >= XFRM_POLICY_MAX || 1795 pol->type != type) 1796 continue; 1797 1798 __xfrm_policy_unlink(pol, dir); 1799 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1800 cnt++; 1801 xfrm_audit_policy_delete(pol, 1, task_valid); 1802 xfrm_policy_kill(pol); 1803 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1804 goto again; 1805 } 1806 if (cnt) 1807 __xfrm_policy_inexact_flush(net); 1808 else 1809 err = -ESRCH; 1810 out: 1811 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1812 return err; 1813 } 1814 EXPORT_SYMBOL(xfrm_policy_flush); 1815 1816 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1817 int (*func)(struct xfrm_policy *, int, int, void*), 1818 void *data) 1819 { 1820 struct xfrm_policy *pol; 1821 struct xfrm_policy_walk_entry *x; 1822 int error = 0; 1823 1824 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1825 walk->type != XFRM_POLICY_TYPE_ANY) 1826 return -EINVAL; 1827 1828 if (list_empty(&walk->walk.all) && walk->seq != 0) 1829 return 0; 1830 1831 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1832 if (list_empty(&walk->walk.all)) 1833 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1834 else 1835 x = list_first_entry(&walk->walk.all, 1836 struct xfrm_policy_walk_entry, all); 1837 1838 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1839 if (x->dead) 1840 continue; 1841 pol = container_of(x, struct xfrm_policy, walk); 1842 if (walk->type != XFRM_POLICY_TYPE_ANY && 1843 walk->type != pol->type) 1844 continue; 1845 error = func(pol, xfrm_policy_id2dir(pol->index), 1846 walk->seq, data); 1847 if (error) { 1848 list_move_tail(&walk->walk.all, &x->all); 1849 goto out; 1850 } 1851 walk->seq++; 1852 } 1853 if (walk->seq == 0) { 1854 error = -ENOENT; 1855 goto out; 1856 } 1857 list_del_init(&walk->walk.all); 1858 out: 1859 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1860 return error; 1861 } 1862 EXPORT_SYMBOL(xfrm_policy_walk); 1863 1864 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1865 { 1866 INIT_LIST_HEAD(&walk->walk.all); 1867 walk->walk.dead = 1; 1868 walk->type = type; 1869 walk->seq = 0; 1870 } 1871 EXPORT_SYMBOL(xfrm_policy_walk_init); 1872 1873 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1874 { 1875 if (list_empty(&walk->walk.all)) 1876 return; 1877 1878 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1879 list_del(&walk->walk.all); 1880 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1881 } 1882 EXPORT_SYMBOL(xfrm_policy_walk_done); 1883 1884 /* 1885 * Find policy to apply to this flow. 1886 * 1887 * Returns 0 if policy found, else an -errno. 1888 */ 1889 static int xfrm_policy_match(const struct xfrm_policy *pol, 1890 const struct flowi *fl, 1891 u8 type, u16 family, int dir, u32 if_id) 1892 { 1893 const struct xfrm_selector *sel = &pol->selector; 1894 int ret = -ESRCH; 1895 bool match; 1896 1897 if (pol->family != family || 1898 pol->if_id != if_id || 1899 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1900 pol->type != type) 1901 return ret; 1902 1903 match = xfrm_selector_match(sel, fl, family); 1904 if (match) 1905 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1906 dir); 1907 return ret; 1908 } 1909 1910 static struct xfrm_pol_inexact_node * 1911 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1912 seqcount_t *count, 1913 const xfrm_address_t *addr, u16 family) 1914 { 1915 const struct rb_node *parent; 1916 int seq; 1917 1918 again: 1919 seq = read_seqcount_begin(count); 1920 1921 parent = rcu_dereference_raw(r->rb_node); 1922 while (parent) { 1923 struct xfrm_pol_inexact_node *node; 1924 int delta; 1925 1926 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1927 1928 delta = xfrm_policy_addr_delta(addr, &node->addr, 1929 node->prefixlen, family); 1930 if (delta < 0) { 1931 parent = rcu_dereference_raw(parent->rb_left); 1932 continue; 1933 } else if (delta > 0) { 1934 parent = rcu_dereference_raw(parent->rb_right); 1935 continue; 1936 } 1937 1938 return node; 1939 } 1940 1941 if (read_seqcount_retry(count, seq)) 1942 goto again; 1943 1944 return NULL; 1945 } 1946 1947 static bool 1948 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1949 struct xfrm_pol_inexact_bin *b, 1950 const xfrm_address_t *saddr, 1951 const xfrm_address_t *daddr) 1952 { 1953 struct xfrm_pol_inexact_node *n; 1954 u16 family; 1955 1956 if (!b) 1957 return false; 1958 1959 family = b->k.family; 1960 memset(cand, 0, sizeof(*cand)); 1961 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1962 1963 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1964 family); 1965 if (n) { 1966 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1967 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1968 family); 1969 if (n) 1970 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1971 } 1972 1973 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1974 family); 1975 if (n) 1976 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1977 1978 return true; 1979 } 1980 1981 static struct xfrm_pol_inexact_bin * 1982 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1983 u8 dir, u32 if_id) 1984 { 1985 struct xfrm_pol_inexact_key k = { 1986 .family = family, 1987 .type = type, 1988 .dir = dir, 1989 .if_id = if_id, 1990 }; 1991 1992 write_pnet(&k.net, net); 1993 1994 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1995 xfrm_pol_inexact_params); 1996 } 1997 1998 static struct xfrm_pol_inexact_bin * 1999 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 2000 u8 dir, u32 if_id) 2001 { 2002 struct xfrm_pol_inexact_bin *bin; 2003 2004 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2005 2006 rcu_read_lock(); 2007 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2008 rcu_read_unlock(); 2009 2010 return bin; 2011 } 2012 2013 static struct xfrm_policy * 2014 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2015 struct xfrm_policy *prefer, 2016 const struct flowi *fl, 2017 u8 type, u16 family, int dir, u32 if_id) 2018 { 2019 u32 priority = prefer ? prefer->priority : ~0u; 2020 struct xfrm_policy *pol; 2021 2022 if (!chain) 2023 return NULL; 2024 2025 hlist_for_each_entry_rcu(pol, chain, bydst) { 2026 int err; 2027 2028 if (pol->priority > priority) 2029 break; 2030 2031 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2032 if (err) { 2033 if (err != -ESRCH) 2034 return ERR_PTR(err); 2035 2036 continue; 2037 } 2038 2039 if (prefer) { 2040 /* matches. Is it older than *prefer? */ 2041 if (pol->priority == priority && 2042 prefer->pos < pol->pos) 2043 return prefer; 2044 } 2045 2046 return pol; 2047 } 2048 2049 return NULL; 2050 } 2051 2052 static struct xfrm_policy * 2053 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2054 struct xfrm_policy *prefer, 2055 const struct flowi *fl, 2056 u8 type, u16 family, int dir, u32 if_id) 2057 { 2058 struct xfrm_policy *tmp; 2059 int i; 2060 2061 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2062 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2063 prefer, 2064 fl, type, family, dir, 2065 if_id); 2066 if (!tmp) 2067 continue; 2068 2069 if (IS_ERR(tmp)) 2070 return tmp; 2071 prefer = tmp; 2072 } 2073 2074 return prefer; 2075 } 2076 2077 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2078 const struct flowi *fl, 2079 u16 family, u8 dir, 2080 u32 if_id) 2081 { 2082 struct xfrm_pol_inexact_candidates cand; 2083 const xfrm_address_t *daddr, *saddr; 2084 struct xfrm_pol_inexact_bin *bin; 2085 struct xfrm_policy *pol, *ret; 2086 struct hlist_head *chain; 2087 unsigned int sequence; 2088 int err; 2089 2090 daddr = xfrm_flowi_daddr(fl, family); 2091 saddr = xfrm_flowi_saddr(fl, family); 2092 if (unlikely(!daddr || !saddr)) 2093 return NULL; 2094 2095 rcu_read_lock(); 2096 retry: 2097 do { 2098 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 2099 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2100 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 2101 2102 ret = NULL; 2103 hlist_for_each_entry_rcu(pol, chain, bydst) { 2104 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2105 if (err) { 2106 if (err == -ESRCH) 2107 continue; 2108 else { 2109 ret = ERR_PTR(err); 2110 goto fail; 2111 } 2112 } else { 2113 ret = pol; 2114 break; 2115 } 2116 } 2117 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2118 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2119 daddr)) 2120 goto skip_inexact; 2121 2122 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2123 family, dir, if_id); 2124 if (pol) { 2125 ret = pol; 2126 if (IS_ERR(pol)) 2127 goto fail; 2128 } 2129 2130 skip_inexact: 2131 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 2132 goto retry; 2133 2134 if (ret && !xfrm_pol_hold_rcu(ret)) 2135 goto retry; 2136 fail: 2137 rcu_read_unlock(); 2138 2139 return ret; 2140 } 2141 2142 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2143 const struct flowi *fl, 2144 u16 family, u8 dir, u32 if_id) 2145 { 2146 #ifdef CONFIG_XFRM_SUB_POLICY 2147 struct xfrm_policy *pol; 2148 2149 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2150 dir, if_id); 2151 if (pol != NULL) 2152 return pol; 2153 #endif 2154 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2155 dir, if_id); 2156 } 2157 2158 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2159 const struct flowi *fl, 2160 u16 family, u32 if_id) 2161 { 2162 struct xfrm_policy *pol; 2163 2164 rcu_read_lock(); 2165 again: 2166 pol = rcu_dereference(sk->sk_policy[dir]); 2167 if (pol != NULL) { 2168 bool match; 2169 int err = 0; 2170 2171 if (pol->family != family) { 2172 pol = NULL; 2173 goto out; 2174 } 2175 2176 match = xfrm_selector_match(&pol->selector, fl, family); 2177 if (match) { 2178 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2179 pol->if_id != if_id) { 2180 pol = NULL; 2181 goto out; 2182 } 2183 err = security_xfrm_policy_lookup(pol->security, 2184 fl->flowi_secid, 2185 dir); 2186 if (!err) { 2187 if (!xfrm_pol_hold_rcu(pol)) 2188 goto again; 2189 } else if (err == -ESRCH) { 2190 pol = NULL; 2191 } else { 2192 pol = ERR_PTR(err); 2193 } 2194 } else 2195 pol = NULL; 2196 } 2197 out: 2198 rcu_read_unlock(); 2199 return pol; 2200 } 2201 2202 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2203 { 2204 struct net *net = xp_net(pol); 2205 2206 list_add(&pol->walk.all, &net->xfrm.policy_all); 2207 net->xfrm.policy_count[dir]++; 2208 xfrm_pol_hold(pol); 2209 } 2210 2211 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2212 int dir) 2213 { 2214 struct net *net = xp_net(pol); 2215 2216 if (list_empty(&pol->walk.all)) 2217 return NULL; 2218 2219 /* Socket policies are not hashed. */ 2220 if (!hlist_unhashed(&pol->bydst)) { 2221 hlist_del_rcu(&pol->bydst); 2222 hlist_del_init(&pol->bydst_inexact_list); 2223 hlist_del(&pol->byidx); 2224 } 2225 2226 list_del_init(&pol->walk.all); 2227 net->xfrm.policy_count[dir]--; 2228 2229 return pol; 2230 } 2231 2232 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2233 { 2234 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2235 } 2236 2237 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2238 { 2239 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2240 } 2241 2242 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2243 { 2244 struct net *net = xp_net(pol); 2245 2246 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2247 pol = __xfrm_policy_unlink(pol, dir); 2248 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2249 if (pol) { 2250 xfrm_policy_kill(pol); 2251 return 0; 2252 } 2253 return -ENOENT; 2254 } 2255 EXPORT_SYMBOL(xfrm_policy_delete); 2256 2257 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2258 { 2259 struct net *net = sock_net(sk); 2260 struct xfrm_policy *old_pol; 2261 2262 #ifdef CONFIG_XFRM_SUB_POLICY 2263 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2264 return -EINVAL; 2265 #endif 2266 2267 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2268 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2269 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2270 if (pol) { 2271 pol->curlft.add_time = ktime_get_real_seconds(); 2272 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2273 xfrm_sk_policy_link(pol, dir); 2274 } 2275 rcu_assign_pointer(sk->sk_policy[dir], pol); 2276 if (old_pol) { 2277 if (pol) 2278 xfrm_policy_requeue(old_pol, pol); 2279 2280 /* Unlinking succeeds always. This is the only function 2281 * allowed to delete or replace socket policy. 2282 */ 2283 xfrm_sk_policy_unlink(old_pol, dir); 2284 } 2285 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2286 2287 if (old_pol) { 2288 xfrm_policy_kill(old_pol); 2289 } 2290 return 0; 2291 } 2292 2293 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2294 { 2295 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2296 struct net *net = xp_net(old); 2297 2298 if (newp) { 2299 newp->selector = old->selector; 2300 if (security_xfrm_policy_clone(old->security, 2301 &newp->security)) { 2302 kfree(newp); 2303 return NULL; /* ENOMEM */ 2304 } 2305 newp->lft = old->lft; 2306 newp->curlft = old->curlft; 2307 newp->mark = old->mark; 2308 newp->if_id = old->if_id; 2309 newp->action = old->action; 2310 newp->flags = old->flags; 2311 newp->xfrm_nr = old->xfrm_nr; 2312 newp->index = old->index; 2313 newp->type = old->type; 2314 newp->family = old->family; 2315 memcpy(newp->xfrm_vec, old->xfrm_vec, 2316 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2317 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2318 xfrm_sk_policy_link(newp, dir); 2319 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2320 xfrm_pol_put(newp); 2321 } 2322 return newp; 2323 } 2324 2325 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2326 { 2327 const struct xfrm_policy *p; 2328 struct xfrm_policy *np; 2329 int i, ret = 0; 2330 2331 rcu_read_lock(); 2332 for (i = 0; i < 2; i++) { 2333 p = rcu_dereference(osk->sk_policy[i]); 2334 if (p) { 2335 np = clone_policy(p, i); 2336 if (unlikely(!np)) { 2337 ret = -ENOMEM; 2338 break; 2339 } 2340 rcu_assign_pointer(sk->sk_policy[i], np); 2341 } 2342 } 2343 rcu_read_unlock(); 2344 return ret; 2345 } 2346 2347 static int 2348 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2349 xfrm_address_t *remote, unsigned short family, u32 mark) 2350 { 2351 int err; 2352 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2353 2354 if (unlikely(afinfo == NULL)) 2355 return -EINVAL; 2356 err = afinfo->get_saddr(net, oif, local, remote, mark); 2357 rcu_read_unlock(); 2358 return err; 2359 } 2360 2361 /* Resolve list of templates for the flow, given policy. */ 2362 2363 static int 2364 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2365 struct xfrm_state **xfrm, unsigned short family) 2366 { 2367 struct net *net = xp_net(policy); 2368 int nx; 2369 int i, error; 2370 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2371 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2372 xfrm_address_t tmp; 2373 2374 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2375 struct xfrm_state *x; 2376 xfrm_address_t *remote = daddr; 2377 xfrm_address_t *local = saddr; 2378 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2379 2380 if (tmpl->mode == XFRM_MODE_TUNNEL || 2381 tmpl->mode == XFRM_MODE_BEET) { 2382 remote = &tmpl->id.daddr; 2383 local = &tmpl->saddr; 2384 if (xfrm_addr_any(local, tmpl->encap_family)) { 2385 error = xfrm_get_saddr(net, fl->flowi_oif, 2386 &tmp, remote, 2387 tmpl->encap_family, 0); 2388 if (error) 2389 goto fail; 2390 local = &tmp; 2391 } 2392 } 2393 2394 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2395 family, policy->if_id); 2396 2397 if (x && x->km.state == XFRM_STATE_VALID) { 2398 xfrm[nx++] = x; 2399 daddr = remote; 2400 saddr = local; 2401 continue; 2402 } 2403 if (x) { 2404 error = (x->km.state == XFRM_STATE_ERROR ? 2405 -EINVAL : -EAGAIN); 2406 xfrm_state_put(x); 2407 } else if (error == -ESRCH) { 2408 error = -EAGAIN; 2409 } 2410 2411 if (!tmpl->optional) 2412 goto fail; 2413 } 2414 return nx; 2415 2416 fail: 2417 for (nx--; nx >= 0; nx--) 2418 xfrm_state_put(xfrm[nx]); 2419 return error; 2420 } 2421 2422 static int 2423 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2424 struct xfrm_state **xfrm, unsigned short family) 2425 { 2426 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2427 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2428 int cnx = 0; 2429 int error; 2430 int ret; 2431 int i; 2432 2433 for (i = 0; i < npols; i++) { 2434 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2435 error = -ENOBUFS; 2436 goto fail; 2437 } 2438 2439 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2440 if (ret < 0) { 2441 error = ret; 2442 goto fail; 2443 } else 2444 cnx += ret; 2445 } 2446 2447 /* found states are sorted for outbound processing */ 2448 if (npols > 1) 2449 xfrm_state_sort(xfrm, tpp, cnx, family); 2450 2451 return cnx; 2452 2453 fail: 2454 for (cnx--; cnx >= 0; cnx--) 2455 xfrm_state_put(tpp[cnx]); 2456 return error; 2457 2458 } 2459 2460 static int xfrm_get_tos(const struct flowi *fl, int family) 2461 { 2462 if (family == AF_INET) 2463 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2464 2465 return 0; 2466 } 2467 2468 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2469 { 2470 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2471 struct dst_ops *dst_ops; 2472 struct xfrm_dst *xdst; 2473 2474 if (!afinfo) 2475 return ERR_PTR(-EINVAL); 2476 2477 switch (family) { 2478 case AF_INET: 2479 dst_ops = &net->xfrm.xfrm4_dst_ops; 2480 break; 2481 #if IS_ENABLED(CONFIG_IPV6) 2482 case AF_INET6: 2483 dst_ops = &net->xfrm.xfrm6_dst_ops; 2484 break; 2485 #endif 2486 default: 2487 BUG(); 2488 } 2489 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2490 2491 if (likely(xdst)) { 2492 struct dst_entry *dst = &xdst->u.dst; 2493 2494 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 2495 } else 2496 xdst = ERR_PTR(-ENOBUFS); 2497 2498 rcu_read_unlock(); 2499 2500 return xdst; 2501 } 2502 2503 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2504 int nfheader_len) 2505 { 2506 if (dst->ops->family == AF_INET6) { 2507 struct rt6_info *rt = (struct rt6_info *)dst; 2508 path->path_cookie = rt6_get_cookie(rt); 2509 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2510 } 2511 } 2512 2513 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2514 const struct flowi *fl) 2515 { 2516 const struct xfrm_policy_afinfo *afinfo = 2517 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2518 int err; 2519 2520 if (!afinfo) 2521 return -EINVAL; 2522 2523 err = afinfo->fill_dst(xdst, dev, fl); 2524 2525 rcu_read_unlock(); 2526 2527 return err; 2528 } 2529 2530 2531 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2532 * all the metrics... Shortly, bundle a bundle. 2533 */ 2534 2535 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2536 struct xfrm_state **xfrm, 2537 struct xfrm_dst **bundle, 2538 int nx, 2539 const struct flowi *fl, 2540 struct dst_entry *dst) 2541 { 2542 const struct xfrm_state_afinfo *afinfo; 2543 const struct xfrm_mode *inner_mode; 2544 struct net *net = xp_net(policy); 2545 unsigned long now = jiffies; 2546 struct net_device *dev; 2547 struct xfrm_dst *xdst_prev = NULL; 2548 struct xfrm_dst *xdst0 = NULL; 2549 int i = 0; 2550 int err; 2551 int header_len = 0; 2552 int nfheader_len = 0; 2553 int trailer_len = 0; 2554 int tos; 2555 int family = policy->selector.family; 2556 xfrm_address_t saddr, daddr; 2557 2558 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2559 2560 tos = xfrm_get_tos(fl, family); 2561 2562 dst_hold(dst); 2563 2564 for (; i < nx; i++) { 2565 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2566 struct dst_entry *dst1 = &xdst->u.dst; 2567 2568 err = PTR_ERR(xdst); 2569 if (IS_ERR(xdst)) { 2570 dst_release(dst); 2571 goto put_states; 2572 } 2573 2574 bundle[i] = xdst; 2575 if (!xdst_prev) 2576 xdst0 = xdst; 2577 else 2578 /* Ref count is taken during xfrm_alloc_dst() 2579 * No need to do dst_clone() on dst1 2580 */ 2581 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2582 2583 if (xfrm[i]->sel.family == AF_UNSPEC) { 2584 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2585 xfrm_af2proto(family)); 2586 if (!inner_mode) { 2587 err = -EAFNOSUPPORT; 2588 dst_release(dst); 2589 goto put_states; 2590 } 2591 } else 2592 inner_mode = &xfrm[i]->inner_mode; 2593 2594 xdst->route = dst; 2595 dst_copy_metrics(dst1, dst); 2596 2597 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2598 __u32 mark = 0; 2599 2600 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2601 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2602 2603 family = xfrm[i]->props.family; 2604 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 2605 &saddr, &daddr, family, mark); 2606 err = PTR_ERR(dst); 2607 if (IS_ERR(dst)) 2608 goto put_states; 2609 } else 2610 dst_hold(dst); 2611 2612 dst1->xfrm = xfrm[i]; 2613 xdst->xfrm_genid = xfrm[i]->genid; 2614 2615 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2616 dst1->flags |= DST_HOST; 2617 dst1->lastuse = now; 2618 2619 dst1->input = dst_discard; 2620 2621 rcu_read_lock(); 2622 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2623 if (likely(afinfo)) 2624 dst1->output = afinfo->output; 2625 else 2626 dst1->output = dst_discard_out; 2627 rcu_read_unlock(); 2628 2629 xdst_prev = xdst; 2630 2631 header_len += xfrm[i]->props.header_len; 2632 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2633 nfheader_len += xfrm[i]->props.header_len; 2634 trailer_len += xfrm[i]->props.trailer_len; 2635 } 2636 2637 xfrm_dst_set_child(xdst_prev, dst); 2638 xdst0->path = dst; 2639 2640 err = -ENODEV; 2641 dev = dst->dev; 2642 if (!dev) 2643 goto free_dst; 2644 2645 xfrm_init_path(xdst0, dst, nfheader_len); 2646 xfrm_init_pmtu(bundle, nx); 2647 2648 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2649 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2650 err = xfrm_fill_dst(xdst_prev, dev, fl); 2651 if (err) 2652 goto free_dst; 2653 2654 xdst_prev->u.dst.header_len = header_len; 2655 xdst_prev->u.dst.trailer_len = trailer_len; 2656 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2657 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2658 } 2659 2660 return &xdst0->u.dst; 2661 2662 put_states: 2663 for (; i < nx; i++) 2664 xfrm_state_put(xfrm[i]); 2665 free_dst: 2666 if (xdst0) 2667 dst_release_immediate(&xdst0->u.dst); 2668 2669 return ERR_PTR(err); 2670 } 2671 2672 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2673 struct xfrm_policy **pols, 2674 int *num_pols, int *num_xfrms) 2675 { 2676 int i; 2677 2678 if (*num_pols == 0 || !pols[0]) { 2679 *num_pols = 0; 2680 *num_xfrms = 0; 2681 return 0; 2682 } 2683 if (IS_ERR(pols[0])) 2684 return PTR_ERR(pols[0]); 2685 2686 *num_xfrms = pols[0]->xfrm_nr; 2687 2688 #ifdef CONFIG_XFRM_SUB_POLICY 2689 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 2690 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2691 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2692 XFRM_POLICY_TYPE_MAIN, 2693 fl, family, 2694 XFRM_POLICY_OUT, 2695 pols[0]->if_id); 2696 if (pols[1]) { 2697 if (IS_ERR(pols[1])) { 2698 xfrm_pols_put(pols, *num_pols); 2699 return PTR_ERR(pols[1]); 2700 } 2701 (*num_pols)++; 2702 (*num_xfrms) += pols[1]->xfrm_nr; 2703 } 2704 } 2705 #endif 2706 for (i = 0; i < *num_pols; i++) { 2707 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2708 *num_xfrms = -1; 2709 break; 2710 } 2711 } 2712 2713 return 0; 2714 2715 } 2716 2717 static struct xfrm_dst * 2718 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2719 const struct flowi *fl, u16 family, 2720 struct dst_entry *dst_orig) 2721 { 2722 struct net *net = xp_net(pols[0]); 2723 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2724 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2725 struct xfrm_dst *xdst; 2726 struct dst_entry *dst; 2727 int err; 2728 2729 /* Try to instantiate a bundle */ 2730 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2731 if (err <= 0) { 2732 if (err == 0) 2733 return NULL; 2734 2735 if (err != -EAGAIN) 2736 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2737 return ERR_PTR(err); 2738 } 2739 2740 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2741 if (IS_ERR(dst)) { 2742 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2743 return ERR_CAST(dst); 2744 } 2745 2746 xdst = (struct xfrm_dst *)dst; 2747 xdst->num_xfrms = err; 2748 xdst->num_pols = num_pols; 2749 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2750 xdst->policy_genid = atomic_read(&pols[0]->genid); 2751 2752 return xdst; 2753 } 2754 2755 static void xfrm_policy_queue_process(struct timer_list *t) 2756 { 2757 struct sk_buff *skb; 2758 struct sock *sk; 2759 struct dst_entry *dst; 2760 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2761 struct net *net = xp_net(pol); 2762 struct xfrm_policy_queue *pq = &pol->polq; 2763 struct flowi fl; 2764 struct sk_buff_head list; 2765 2766 spin_lock(&pq->hold_queue.lock); 2767 skb = skb_peek(&pq->hold_queue); 2768 if (!skb) { 2769 spin_unlock(&pq->hold_queue.lock); 2770 goto out; 2771 } 2772 dst = skb_dst(skb); 2773 sk = skb->sk; 2774 xfrm_decode_session(skb, &fl, dst->ops->family); 2775 spin_unlock(&pq->hold_queue.lock); 2776 2777 dst_hold(xfrm_dst_path(dst)); 2778 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2779 if (IS_ERR(dst)) 2780 goto purge_queue; 2781 2782 if (dst->flags & DST_XFRM_QUEUE) { 2783 dst_release(dst); 2784 2785 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2786 goto purge_queue; 2787 2788 pq->timeout = pq->timeout << 1; 2789 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2790 xfrm_pol_hold(pol); 2791 goto out; 2792 } 2793 2794 dst_release(dst); 2795 2796 __skb_queue_head_init(&list); 2797 2798 spin_lock(&pq->hold_queue.lock); 2799 pq->timeout = 0; 2800 skb_queue_splice_init(&pq->hold_queue, &list); 2801 spin_unlock(&pq->hold_queue.lock); 2802 2803 while (!skb_queue_empty(&list)) { 2804 skb = __skb_dequeue(&list); 2805 2806 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2807 dst_hold(xfrm_dst_path(skb_dst(skb))); 2808 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2809 if (IS_ERR(dst)) { 2810 kfree_skb(skb); 2811 continue; 2812 } 2813 2814 nf_reset_ct(skb); 2815 skb_dst_drop(skb); 2816 skb_dst_set(skb, dst); 2817 2818 dst_output(net, skb->sk, skb); 2819 } 2820 2821 out: 2822 xfrm_pol_put(pol); 2823 return; 2824 2825 purge_queue: 2826 pq->timeout = 0; 2827 skb_queue_purge(&pq->hold_queue); 2828 xfrm_pol_put(pol); 2829 } 2830 2831 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2832 { 2833 unsigned long sched_next; 2834 struct dst_entry *dst = skb_dst(skb); 2835 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2836 struct xfrm_policy *pol = xdst->pols[0]; 2837 struct xfrm_policy_queue *pq = &pol->polq; 2838 2839 if (unlikely(skb_fclone_busy(sk, skb))) { 2840 kfree_skb(skb); 2841 return 0; 2842 } 2843 2844 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2845 kfree_skb(skb); 2846 return -EAGAIN; 2847 } 2848 2849 skb_dst_force(skb); 2850 2851 spin_lock_bh(&pq->hold_queue.lock); 2852 2853 if (!pq->timeout) 2854 pq->timeout = XFRM_QUEUE_TMO_MIN; 2855 2856 sched_next = jiffies + pq->timeout; 2857 2858 if (del_timer(&pq->hold_timer)) { 2859 if (time_before(pq->hold_timer.expires, sched_next)) 2860 sched_next = pq->hold_timer.expires; 2861 xfrm_pol_put(pol); 2862 } 2863 2864 __skb_queue_tail(&pq->hold_queue, skb); 2865 if (!mod_timer(&pq->hold_timer, sched_next)) 2866 xfrm_pol_hold(pol); 2867 2868 spin_unlock_bh(&pq->hold_queue.lock); 2869 2870 return 0; 2871 } 2872 2873 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2874 struct xfrm_flo *xflo, 2875 const struct flowi *fl, 2876 int num_xfrms, 2877 u16 family) 2878 { 2879 int err; 2880 struct net_device *dev; 2881 struct dst_entry *dst; 2882 struct dst_entry *dst1; 2883 struct xfrm_dst *xdst; 2884 2885 xdst = xfrm_alloc_dst(net, family); 2886 if (IS_ERR(xdst)) 2887 return xdst; 2888 2889 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2890 net->xfrm.sysctl_larval_drop || 2891 num_xfrms <= 0) 2892 return xdst; 2893 2894 dst = xflo->dst_orig; 2895 dst1 = &xdst->u.dst; 2896 dst_hold(dst); 2897 xdst->route = dst; 2898 2899 dst_copy_metrics(dst1, dst); 2900 2901 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2902 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2903 dst1->lastuse = jiffies; 2904 2905 dst1->input = dst_discard; 2906 dst1->output = xdst_queue_output; 2907 2908 dst_hold(dst); 2909 xfrm_dst_set_child(xdst, dst); 2910 xdst->path = dst; 2911 2912 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2913 2914 err = -ENODEV; 2915 dev = dst->dev; 2916 if (!dev) 2917 goto free_dst; 2918 2919 err = xfrm_fill_dst(xdst, dev, fl); 2920 if (err) 2921 goto free_dst; 2922 2923 out: 2924 return xdst; 2925 2926 free_dst: 2927 dst_release(dst1); 2928 xdst = ERR_PTR(err); 2929 goto out; 2930 } 2931 2932 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2933 const struct flowi *fl, 2934 u16 family, u8 dir, 2935 struct xfrm_flo *xflo, u32 if_id) 2936 { 2937 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2938 int num_pols = 0, num_xfrms = 0, err; 2939 struct xfrm_dst *xdst; 2940 2941 /* Resolve policies to use if we couldn't get them from 2942 * previous cache entry */ 2943 num_pols = 1; 2944 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2945 err = xfrm_expand_policies(fl, family, pols, 2946 &num_pols, &num_xfrms); 2947 if (err < 0) 2948 goto inc_error; 2949 if (num_pols == 0) 2950 return NULL; 2951 if (num_xfrms <= 0) 2952 goto make_dummy_bundle; 2953 2954 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2955 xflo->dst_orig); 2956 if (IS_ERR(xdst)) { 2957 err = PTR_ERR(xdst); 2958 if (err == -EREMOTE) { 2959 xfrm_pols_put(pols, num_pols); 2960 return NULL; 2961 } 2962 2963 if (err != -EAGAIN) 2964 goto error; 2965 goto make_dummy_bundle; 2966 } else if (xdst == NULL) { 2967 num_xfrms = 0; 2968 goto make_dummy_bundle; 2969 } 2970 2971 return xdst; 2972 2973 make_dummy_bundle: 2974 /* We found policies, but there's no bundles to instantiate: 2975 * either because the policy blocks, has no transformations or 2976 * we could not build template (no xfrm_states).*/ 2977 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2978 if (IS_ERR(xdst)) { 2979 xfrm_pols_put(pols, num_pols); 2980 return ERR_CAST(xdst); 2981 } 2982 xdst->num_pols = num_pols; 2983 xdst->num_xfrms = num_xfrms; 2984 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2985 2986 return xdst; 2987 2988 inc_error: 2989 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2990 error: 2991 xfrm_pols_put(pols, num_pols); 2992 return ERR_PTR(err); 2993 } 2994 2995 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2996 struct dst_entry *dst_orig) 2997 { 2998 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2999 struct dst_entry *ret; 3000 3001 if (!afinfo) { 3002 dst_release(dst_orig); 3003 return ERR_PTR(-EINVAL); 3004 } else { 3005 ret = afinfo->blackhole_route(net, dst_orig); 3006 } 3007 rcu_read_unlock(); 3008 3009 return ret; 3010 } 3011 3012 /* Finds/creates a bundle for given flow and if_id 3013 * 3014 * At the moment we eat a raw IP route. Mostly to speed up lookups 3015 * on interfaces with disabled IPsec. 3016 * 3017 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3018 * compatibility 3019 */ 3020 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3021 struct dst_entry *dst_orig, 3022 const struct flowi *fl, 3023 const struct sock *sk, 3024 int flags, u32 if_id) 3025 { 3026 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3027 struct xfrm_dst *xdst; 3028 struct dst_entry *dst, *route; 3029 u16 family = dst_orig->ops->family; 3030 u8 dir = XFRM_POLICY_OUT; 3031 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3032 3033 dst = NULL; 3034 xdst = NULL; 3035 route = NULL; 3036 3037 sk = sk_const_to_full_sk(sk); 3038 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3039 num_pols = 1; 3040 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3041 if_id); 3042 err = xfrm_expand_policies(fl, family, pols, 3043 &num_pols, &num_xfrms); 3044 if (err < 0) 3045 goto dropdst; 3046 3047 if (num_pols) { 3048 if (num_xfrms <= 0) { 3049 drop_pols = num_pols; 3050 goto no_transform; 3051 } 3052 3053 xdst = xfrm_resolve_and_create_bundle( 3054 pols, num_pols, fl, 3055 family, dst_orig); 3056 3057 if (IS_ERR(xdst)) { 3058 xfrm_pols_put(pols, num_pols); 3059 err = PTR_ERR(xdst); 3060 if (err == -EREMOTE) 3061 goto nopol; 3062 3063 goto dropdst; 3064 } else if (xdst == NULL) { 3065 num_xfrms = 0; 3066 drop_pols = num_pols; 3067 goto no_transform; 3068 } 3069 3070 route = xdst->route; 3071 } 3072 } 3073 3074 if (xdst == NULL) { 3075 struct xfrm_flo xflo; 3076 3077 xflo.dst_orig = dst_orig; 3078 xflo.flags = flags; 3079 3080 /* To accelerate a bit... */ 3081 if ((dst_orig->flags & DST_NOXFRM) || 3082 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 3083 goto nopol; 3084 3085 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3086 if (xdst == NULL) 3087 goto nopol; 3088 if (IS_ERR(xdst)) { 3089 err = PTR_ERR(xdst); 3090 goto dropdst; 3091 } 3092 3093 num_pols = xdst->num_pols; 3094 num_xfrms = xdst->num_xfrms; 3095 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3096 route = xdst->route; 3097 } 3098 3099 dst = &xdst->u.dst; 3100 if (route == NULL && num_xfrms > 0) { 3101 /* The only case when xfrm_bundle_lookup() returns a 3102 * bundle with null route, is when the template could 3103 * not be resolved. It means policies are there, but 3104 * bundle could not be created, since we don't yet 3105 * have the xfrm_state's. We need to wait for KM to 3106 * negotiate new SA's or bail out with error.*/ 3107 if (net->xfrm.sysctl_larval_drop) { 3108 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3109 err = -EREMOTE; 3110 goto error; 3111 } 3112 3113 err = -EAGAIN; 3114 3115 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3116 goto error; 3117 } 3118 3119 no_transform: 3120 if (num_pols == 0) 3121 goto nopol; 3122 3123 if ((flags & XFRM_LOOKUP_ICMP) && 3124 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3125 err = -ENOENT; 3126 goto error; 3127 } 3128 3129 for (i = 0; i < num_pols; i++) 3130 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3131 3132 if (num_xfrms < 0) { 3133 /* Prohibit the flow */ 3134 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3135 err = -EPERM; 3136 goto error; 3137 } else if (num_xfrms > 0) { 3138 /* Flow transformed */ 3139 dst_release(dst_orig); 3140 } else { 3141 /* Flow passes untransformed */ 3142 dst_release(dst); 3143 dst = dst_orig; 3144 } 3145 ok: 3146 xfrm_pols_put(pols, drop_pols); 3147 if (dst && dst->xfrm && 3148 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3149 dst->flags |= DST_XFRM_TUNNEL; 3150 return dst; 3151 3152 nopol: 3153 if (!(flags & XFRM_LOOKUP_ICMP)) { 3154 dst = dst_orig; 3155 goto ok; 3156 } 3157 err = -ENOENT; 3158 error: 3159 dst_release(dst); 3160 dropdst: 3161 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3162 dst_release(dst_orig); 3163 xfrm_pols_put(pols, drop_pols); 3164 return ERR_PTR(err); 3165 } 3166 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3167 3168 /* Main function: finds/creates a bundle for given flow. 3169 * 3170 * At the moment we eat a raw IP route. Mostly to speed up lookups 3171 * on interfaces with disabled IPsec. 3172 */ 3173 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3174 const struct flowi *fl, const struct sock *sk, 3175 int flags) 3176 { 3177 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3178 } 3179 EXPORT_SYMBOL(xfrm_lookup); 3180 3181 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3182 * Otherwise we may send out blackholed packets. 3183 */ 3184 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3185 const struct flowi *fl, 3186 const struct sock *sk, int flags) 3187 { 3188 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3189 flags | XFRM_LOOKUP_QUEUE | 3190 XFRM_LOOKUP_KEEP_DST_REF); 3191 3192 if (PTR_ERR(dst) == -EREMOTE) 3193 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3194 3195 if (IS_ERR(dst)) 3196 dst_release(dst_orig); 3197 3198 return dst; 3199 } 3200 EXPORT_SYMBOL(xfrm_lookup_route); 3201 3202 static inline int 3203 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3204 { 3205 struct sec_path *sp = skb_sec_path(skb); 3206 struct xfrm_state *x; 3207 3208 if (!sp || idx < 0 || idx >= sp->len) 3209 return 0; 3210 x = sp->xvec[idx]; 3211 if (!x->type->reject) 3212 return 0; 3213 return x->type->reject(x, skb, fl); 3214 } 3215 3216 /* When skb is transformed back to its "native" form, we have to 3217 * check policy restrictions. At the moment we make this in maximally 3218 * stupid way. Shame on me. :-) Of course, connected sockets must 3219 * have policy cached at them. 3220 */ 3221 3222 static inline int 3223 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3224 unsigned short family) 3225 { 3226 if (xfrm_state_kern(x)) 3227 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3228 return x->id.proto == tmpl->id.proto && 3229 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3230 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3231 x->props.mode == tmpl->mode && 3232 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3233 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3234 !(x->props.mode != XFRM_MODE_TRANSPORT && 3235 xfrm_state_addr_cmp(tmpl, x, family)); 3236 } 3237 3238 /* 3239 * 0 or more than 0 is returned when validation is succeeded (either bypass 3240 * because of optional transport mode, or next index of the mathced secpath 3241 * state with the template. 3242 * -1 is returned when no matching template is found. 3243 * Otherwise "-2 - errored_index" is returned. 3244 */ 3245 static inline int 3246 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3247 unsigned short family) 3248 { 3249 int idx = start; 3250 3251 if (tmpl->optional) { 3252 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3253 return start; 3254 } else 3255 start = -1; 3256 for (; idx < sp->len; idx++) { 3257 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3258 return ++idx; 3259 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3260 if (start == -1) 3261 start = -2-idx; 3262 break; 3263 } 3264 } 3265 return start; 3266 } 3267 3268 static void 3269 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3270 { 3271 const struct iphdr *iph = ip_hdr(skb); 3272 int ihl = iph->ihl; 3273 u8 *xprth = skb_network_header(skb) + ihl * 4; 3274 struct flowi4 *fl4 = &fl->u.ip4; 3275 int oif = 0; 3276 3277 if (skb_dst(skb) && skb_dst(skb)->dev) 3278 oif = skb_dst(skb)->dev->ifindex; 3279 3280 memset(fl4, 0, sizeof(struct flowi4)); 3281 fl4->flowi4_mark = skb->mark; 3282 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3283 3284 fl4->flowi4_proto = iph->protocol; 3285 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3286 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3287 fl4->flowi4_tos = iph->tos; 3288 3289 if (!ip_is_fragment(iph)) { 3290 switch (iph->protocol) { 3291 case IPPROTO_UDP: 3292 case IPPROTO_UDPLITE: 3293 case IPPROTO_TCP: 3294 case IPPROTO_SCTP: 3295 case IPPROTO_DCCP: 3296 if (xprth + 4 < skb->data || 3297 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3298 __be16 *ports; 3299 3300 xprth = skb_network_header(skb) + ihl * 4; 3301 ports = (__be16 *)xprth; 3302 3303 fl4->fl4_sport = ports[!!reverse]; 3304 fl4->fl4_dport = ports[!reverse]; 3305 } 3306 break; 3307 case IPPROTO_ICMP: 3308 if (xprth + 2 < skb->data || 3309 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3310 u8 *icmp; 3311 3312 xprth = skb_network_header(skb) + ihl * 4; 3313 icmp = xprth; 3314 3315 fl4->fl4_icmp_type = icmp[0]; 3316 fl4->fl4_icmp_code = icmp[1]; 3317 } 3318 break; 3319 case IPPROTO_ESP: 3320 if (xprth + 4 < skb->data || 3321 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3322 __be32 *ehdr; 3323 3324 xprth = skb_network_header(skb) + ihl * 4; 3325 ehdr = (__be32 *)xprth; 3326 3327 fl4->fl4_ipsec_spi = ehdr[0]; 3328 } 3329 break; 3330 case IPPROTO_AH: 3331 if (xprth + 8 < skb->data || 3332 pskb_may_pull(skb, xprth + 8 - skb->data)) { 3333 __be32 *ah_hdr; 3334 3335 xprth = skb_network_header(skb) + ihl * 4; 3336 ah_hdr = (__be32 *)xprth; 3337 3338 fl4->fl4_ipsec_spi = ah_hdr[1]; 3339 } 3340 break; 3341 case IPPROTO_COMP: 3342 if (xprth + 4 < skb->data || 3343 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3344 __be16 *ipcomp_hdr; 3345 3346 xprth = skb_network_header(skb) + ihl * 4; 3347 ipcomp_hdr = (__be16 *)xprth; 3348 3349 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); 3350 } 3351 break; 3352 case IPPROTO_GRE: 3353 if (xprth + 12 < skb->data || 3354 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3355 __be16 *greflags; 3356 __be32 *gre_hdr; 3357 3358 xprth = skb_network_header(skb) + ihl * 4; 3359 greflags = (__be16 *)xprth; 3360 gre_hdr = (__be32 *)xprth; 3361 3362 if (greflags[0] & GRE_KEY) { 3363 if (greflags[0] & GRE_CSUM) 3364 gre_hdr++; 3365 fl4->fl4_gre_key = gre_hdr[1]; 3366 } 3367 } 3368 break; 3369 default: 3370 fl4->fl4_ipsec_spi = 0; 3371 break; 3372 } 3373 } 3374 } 3375 3376 #if IS_ENABLED(CONFIG_IPV6) 3377 static void 3378 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3379 { 3380 struct flowi6 *fl6 = &fl->u.ip6; 3381 int onlyproto = 0; 3382 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3383 u32 offset = sizeof(*hdr); 3384 struct ipv6_opt_hdr *exthdr; 3385 const unsigned char *nh = skb_network_header(skb); 3386 u16 nhoff = IP6CB(skb)->nhoff; 3387 int oif = 0; 3388 u8 nexthdr; 3389 3390 if (!nhoff) 3391 nhoff = offsetof(struct ipv6hdr, nexthdr); 3392 3393 nexthdr = nh[nhoff]; 3394 3395 if (skb_dst(skb) && skb_dst(skb)->dev) 3396 oif = skb_dst(skb)->dev->ifindex; 3397 3398 memset(fl6, 0, sizeof(struct flowi6)); 3399 fl6->flowi6_mark = skb->mark; 3400 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3401 3402 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3403 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3404 3405 while (nh + offset + sizeof(*exthdr) < skb->data || 3406 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3407 nh = skb_network_header(skb); 3408 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3409 3410 switch (nexthdr) { 3411 case NEXTHDR_FRAGMENT: 3412 onlyproto = 1; 3413 /* fall through */ 3414 case NEXTHDR_ROUTING: 3415 case NEXTHDR_HOP: 3416 case NEXTHDR_DEST: 3417 offset += ipv6_optlen(exthdr); 3418 nexthdr = exthdr->nexthdr; 3419 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3420 break; 3421 case IPPROTO_UDP: 3422 case IPPROTO_UDPLITE: 3423 case IPPROTO_TCP: 3424 case IPPROTO_SCTP: 3425 case IPPROTO_DCCP: 3426 if (!onlyproto && (nh + offset + 4 < skb->data || 3427 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3428 __be16 *ports; 3429 3430 nh = skb_network_header(skb); 3431 ports = (__be16 *)(nh + offset); 3432 fl6->fl6_sport = ports[!!reverse]; 3433 fl6->fl6_dport = ports[!reverse]; 3434 } 3435 fl6->flowi6_proto = nexthdr; 3436 return; 3437 case IPPROTO_ICMPV6: 3438 if (!onlyproto && (nh + offset + 2 < skb->data || 3439 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3440 u8 *icmp; 3441 3442 nh = skb_network_header(skb); 3443 icmp = (u8 *)(nh + offset); 3444 fl6->fl6_icmp_type = icmp[0]; 3445 fl6->fl6_icmp_code = icmp[1]; 3446 } 3447 fl6->flowi6_proto = nexthdr; 3448 return; 3449 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3450 case IPPROTO_MH: 3451 offset += ipv6_optlen(exthdr); 3452 if (!onlyproto && (nh + offset + 3 < skb->data || 3453 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3454 struct ip6_mh *mh; 3455 3456 nh = skb_network_header(skb); 3457 mh = (struct ip6_mh *)(nh + offset); 3458 fl6->fl6_mh_type = mh->ip6mh_type; 3459 } 3460 fl6->flowi6_proto = nexthdr; 3461 return; 3462 #endif 3463 /* XXX Why are there these headers? */ 3464 case IPPROTO_AH: 3465 case IPPROTO_ESP: 3466 case IPPROTO_COMP: 3467 default: 3468 fl6->fl6_ipsec_spi = 0; 3469 fl6->flowi6_proto = nexthdr; 3470 return; 3471 } 3472 } 3473 } 3474 #endif 3475 3476 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3477 unsigned int family, int reverse) 3478 { 3479 switch (family) { 3480 case AF_INET: 3481 decode_session4(skb, fl, reverse); 3482 break; 3483 #if IS_ENABLED(CONFIG_IPV6) 3484 case AF_INET6: 3485 decode_session6(skb, fl, reverse); 3486 break; 3487 #endif 3488 default: 3489 return -EAFNOSUPPORT; 3490 } 3491 3492 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3493 } 3494 EXPORT_SYMBOL(__xfrm_decode_session); 3495 3496 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3497 { 3498 for (; k < sp->len; k++) { 3499 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3500 *idxp = k; 3501 return 1; 3502 } 3503 } 3504 3505 return 0; 3506 } 3507 3508 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3509 unsigned short family) 3510 { 3511 struct net *net = dev_net(skb->dev); 3512 struct xfrm_policy *pol; 3513 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3514 int npols = 0; 3515 int xfrm_nr; 3516 int pi; 3517 int reverse; 3518 struct flowi fl; 3519 int xerr_idx = -1; 3520 const struct xfrm_if_cb *ifcb; 3521 struct sec_path *sp; 3522 struct xfrm_if *xi; 3523 u32 if_id = 0; 3524 3525 rcu_read_lock(); 3526 ifcb = xfrm_if_get_cb(); 3527 3528 if (ifcb) { 3529 xi = ifcb->decode_session(skb, family); 3530 if (xi) { 3531 if_id = xi->p.if_id; 3532 net = xi->net; 3533 } 3534 } 3535 rcu_read_unlock(); 3536 3537 reverse = dir & ~XFRM_POLICY_MASK; 3538 dir &= XFRM_POLICY_MASK; 3539 3540 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3541 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3542 return 0; 3543 } 3544 3545 nf_nat_decode_session(skb, &fl, family); 3546 3547 /* First, check used SA against their selectors. */ 3548 sp = skb_sec_path(skb); 3549 if (sp) { 3550 int i; 3551 3552 for (i = sp->len - 1; i >= 0; i--) { 3553 struct xfrm_state *x = sp->xvec[i]; 3554 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3555 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3556 return 0; 3557 } 3558 } 3559 } 3560 3561 pol = NULL; 3562 sk = sk_to_full_sk(sk); 3563 if (sk && sk->sk_policy[dir]) { 3564 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3565 if (IS_ERR(pol)) { 3566 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3567 return 0; 3568 } 3569 } 3570 3571 if (!pol) 3572 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3573 3574 if (IS_ERR(pol)) { 3575 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3576 return 0; 3577 } 3578 3579 if (!pol) { 3580 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3581 xfrm_secpath_reject(xerr_idx, skb, &fl); 3582 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3583 return 0; 3584 } 3585 return 1; 3586 } 3587 3588 pol->curlft.use_time = ktime_get_real_seconds(); 3589 3590 pols[0] = pol; 3591 npols++; 3592 #ifdef CONFIG_XFRM_SUB_POLICY 3593 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3594 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3595 &fl, family, 3596 XFRM_POLICY_IN, if_id); 3597 if (pols[1]) { 3598 if (IS_ERR(pols[1])) { 3599 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3600 return 0; 3601 } 3602 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3603 npols++; 3604 } 3605 } 3606 #endif 3607 3608 if (pol->action == XFRM_POLICY_ALLOW) { 3609 static struct sec_path dummy; 3610 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3611 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3612 struct xfrm_tmpl **tpp = tp; 3613 int ti = 0; 3614 int i, k; 3615 3616 sp = skb_sec_path(skb); 3617 if (!sp) 3618 sp = &dummy; 3619 3620 for (pi = 0; pi < npols; pi++) { 3621 if (pols[pi] != pol && 3622 pols[pi]->action != XFRM_POLICY_ALLOW) { 3623 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3624 goto reject; 3625 } 3626 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3627 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3628 goto reject_error; 3629 } 3630 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3631 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3632 } 3633 xfrm_nr = ti; 3634 if (npols > 1) { 3635 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3636 tpp = stp; 3637 } 3638 3639 /* For each tunnel xfrm, find the first matching tmpl. 3640 * For each tmpl before that, find corresponding xfrm. 3641 * Order is _important_. Later we will implement 3642 * some barriers, but at the moment barriers 3643 * are implied between each two transformations. 3644 */ 3645 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3646 k = xfrm_policy_ok(tpp[i], sp, k, family); 3647 if (k < 0) { 3648 if (k < -1) 3649 /* "-2 - errored_index" returned */ 3650 xerr_idx = -(2+k); 3651 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3652 goto reject; 3653 } 3654 } 3655 3656 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3657 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3658 goto reject; 3659 } 3660 3661 xfrm_pols_put(pols, npols); 3662 return 1; 3663 } 3664 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3665 3666 reject: 3667 xfrm_secpath_reject(xerr_idx, skb, &fl); 3668 reject_error: 3669 xfrm_pols_put(pols, npols); 3670 return 0; 3671 } 3672 EXPORT_SYMBOL(__xfrm_policy_check); 3673 3674 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3675 { 3676 struct net *net = dev_net(skb->dev); 3677 struct flowi fl; 3678 struct dst_entry *dst; 3679 int res = 1; 3680 3681 if (xfrm_decode_session(skb, &fl, family) < 0) { 3682 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3683 return 0; 3684 } 3685 3686 skb_dst_force(skb); 3687 if (!skb_dst(skb)) { 3688 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3689 return 0; 3690 } 3691 3692 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3693 if (IS_ERR(dst)) { 3694 res = 0; 3695 dst = NULL; 3696 } 3697 skb_dst_set(skb, dst); 3698 return res; 3699 } 3700 EXPORT_SYMBOL(__xfrm_route_forward); 3701 3702 /* Optimize later using cookies and generation ids. */ 3703 3704 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3705 { 3706 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3707 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3708 * get validated by dst_ops->check on every use. We do this 3709 * because when a normal route referenced by an XFRM dst is 3710 * obsoleted we do not go looking around for all parent 3711 * referencing XFRM dsts so that we can invalidate them. It 3712 * is just too much work. Instead we make the checks here on 3713 * every use. For example: 3714 * 3715 * XFRM dst A --> IPv4 dst X 3716 * 3717 * X is the "xdst->route" of A (X is also the "dst->path" of A 3718 * in this example). If X is marked obsolete, "A" will not 3719 * notice. That's what we are validating here via the 3720 * stale_bundle() check. 3721 * 3722 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3723 * be marked on it. 3724 * This will force stale_bundle() to fail on any xdst bundle with 3725 * this dst linked in it. 3726 */ 3727 if (dst->obsolete < 0 && !stale_bundle(dst)) 3728 return dst; 3729 3730 return NULL; 3731 } 3732 3733 static int stale_bundle(struct dst_entry *dst) 3734 { 3735 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3736 } 3737 3738 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3739 { 3740 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3741 dst->dev = dev_net(dev)->loopback_dev; 3742 dev_hold(dst->dev); 3743 dev_put(dev); 3744 } 3745 } 3746 EXPORT_SYMBOL(xfrm_dst_ifdown); 3747 3748 static void xfrm_link_failure(struct sk_buff *skb) 3749 { 3750 /* Impossible. Such dst must be popped before reaches point of failure. */ 3751 } 3752 3753 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3754 { 3755 if (dst) { 3756 if (dst->obsolete) { 3757 dst_release(dst); 3758 dst = NULL; 3759 } 3760 } 3761 return dst; 3762 } 3763 3764 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3765 { 3766 while (nr--) { 3767 struct xfrm_dst *xdst = bundle[nr]; 3768 u32 pmtu, route_mtu_cached; 3769 struct dst_entry *dst; 3770 3771 dst = &xdst->u.dst; 3772 pmtu = dst_mtu(xfrm_dst_child(dst)); 3773 xdst->child_mtu_cached = pmtu; 3774 3775 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3776 3777 route_mtu_cached = dst_mtu(xdst->route); 3778 xdst->route_mtu_cached = route_mtu_cached; 3779 3780 if (pmtu > route_mtu_cached) 3781 pmtu = route_mtu_cached; 3782 3783 dst_metric_set(dst, RTAX_MTU, pmtu); 3784 } 3785 } 3786 3787 /* Check that the bundle accepts the flow and its components are 3788 * still valid. 3789 */ 3790 3791 static int xfrm_bundle_ok(struct xfrm_dst *first) 3792 { 3793 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3794 struct dst_entry *dst = &first->u.dst; 3795 struct xfrm_dst *xdst; 3796 int start_from, nr; 3797 u32 mtu; 3798 3799 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3800 (dst->dev && !netif_running(dst->dev))) 3801 return 0; 3802 3803 if (dst->flags & DST_XFRM_QUEUE) 3804 return 1; 3805 3806 start_from = nr = 0; 3807 do { 3808 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3809 3810 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3811 return 0; 3812 if (xdst->xfrm_genid != dst->xfrm->genid) 3813 return 0; 3814 if (xdst->num_pols > 0 && 3815 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3816 return 0; 3817 3818 bundle[nr++] = xdst; 3819 3820 mtu = dst_mtu(xfrm_dst_child(dst)); 3821 if (xdst->child_mtu_cached != mtu) { 3822 start_from = nr; 3823 xdst->child_mtu_cached = mtu; 3824 } 3825 3826 if (!dst_check(xdst->route, xdst->route_cookie)) 3827 return 0; 3828 mtu = dst_mtu(xdst->route); 3829 if (xdst->route_mtu_cached != mtu) { 3830 start_from = nr; 3831 xdst->route_mtu_cached = mtu; 3832 } 3833 3834 dst = xfrm_dst_child(dst); 3835 } while (dst->xfrm); 3836 3837 if (likely(!start_from)) 3838 return 1; 3839 3840 xdst = bundle[start_from - 1]; 3841 mtu = xdst->child_mtu_cached; 3842 while (start_from--) { 3843 dst = &xdst->u.dst; 3844 3845 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3846 if (mtu > xdst->route_mtu_cached) 3847 mtu = xdst->route_mtu_cached; 3848 dst_metric_set(dst, RTAX_MTU, mtu); 3849 if (!start_from) 3850 break; 3851 3852 xdst = bundle[start_from - 1]; 3853 xdst->child_mtu_cached = mtu; 3854 } 3855 3856 return 1; 3857 } 3858 3859 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3860 { 3861 return dst_metric_advmss(xfrm_dst_path(dst)); 3862 } 3863 3864 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3865 { 3866 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3867 3868 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3869 } 3870 3871 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3872 const void *daddr) 3873 { 3874 while (dst->xfrm) { 3875 const struct xfrm_state *xfrm = dst->xfrm; 3876 3877 dst = xfrm_dst_child(dst); 3878 3879 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3880 continue; 3881 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3882 daddr = xfrm->coaddr; 3883 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3884 daddr = &xfrm->id.daddr; 3885 } 3886 return daddr; 3887 } 3888 3889 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3890 struct sk_buff *skb, 3891 const void *daddr) 3892 { 3893 const struct dst_entry *path = xfrm_dst_path(dst); 3894 3895 if (!skb) 3896 daddr = xfrm_get_dst_nexthop(dst, daddr); 3897 return path->ops->neigh_lookup(path, skb, daddr); 3898 } 3899 3900 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3901 { 3902 const struct dst_entry *path = xfrm_dst_path(dst); 3903 3904 daddr = xfrm_get_dst_nexthop(dst, daddr); 3905 path->ops->confirm_neigh(path, daddr); 3906 } 3907 3908 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3909 { 3910 int err = 0; 3911 3912 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3913 return -EAFNOSUPPORT; 3914 3915 spin_lock(&xfrm_policy_afinfo_lock); 3916 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3917 err = -EEXIST; 3918 else { 3919 struct dst_ops *dst_ops = afinfo->dst_ops; 3920 if (likely(dst_ops->kmem_cachep == NULL)) 3921 dst_ops->kmem_cachep = xfrm_dst_cache; 3922 if (likely(dst_ops->check == NULL)) 3923 dst_ops->check = xfrm_dst_check; 3924 if (likely(dst_ops->default_advmss == NULL)) 3925 dst_ops->default_advmss = xfrm_default_advmss; 3926 if (likely(dst_ops->mtu == NULL)) 3927 dst_ops->mtu = xfrm_mtu; 3928 if (likely(dst_ops->negative_advice == NULL)) 3929 dst_ops->negative_advice = xfrm_negative_advice; 3930 if (likely(dst_ops->link_failure == NULL)) 3931 dst_ops->link_failure = xfrm_link_failure; 3932 if (likely(dst_ops->neigh_lookup == NULL)) 3933 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3934 if (likely(!dst_ops->confirm_neigh)) 3935 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3936 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3937 } 3938 spin_unlock(&xfrm_policy_afinfo_lock); 3939 3940 return err; 3941 } 3942 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3943 3944 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3945 { 3946 struct dst_ops *dst_ops = afinfo->dst_ops; 3947 int i; 3948 3949 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3950 if (xfrm_policy_afinfo[i] != afinfo) 3951 continue; 3952 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3953 break; 3954 } 3955 3956 synchronize_rcu(); 3957 3958 dst_ops->kmem_cachep = NULL; 3959 dst_ops->check = NULL; 3960 dst_ops->negative_advice = NULL; 3961 dst_ops->link_failure = NULL; 3962 } 3963 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3964 3965 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3966 { 3967 spin_lock(&xfrm_if_cb_lock); 3968 rcu_assign_pointer(xfrm_if_cb, ifcb); 3969 spin_unlock(&xfrm_if_cb_lock); 3970 } 3971 EXPORT_SYMBOL(xfrm_if_register_cb); 3972 3973 void xfrm_if_unregister_cb(void) 3974 { 3975 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3976 synchronize_rcu(); 3977 } 3978 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3979 3980 #ifdef CONFIG_XFRM_STATISTICS 3981 static int __net_init xfrm_statistics_init(struct net *net) 3982 { 3983 int rv; 3984 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3985 if (!net->mib.xfrm_statistics) 3986 return -ENOMEM; 3987 rv = xfrm_proc_init(net); 3988 if (rv < 0) 3989 free_percpu(net->mib.xfrm_statistics); 3990 return rv; 3991 } 3992 3993 static void xfrm_statistics_fini(struct net *net) 3994 { 3995 xfrm_proc_fini(net); 3996 free_percpu(net->mib.xfrm_statistics); 3997 } 3998 #else 3999 static int __net_init xfrm_statistics_init(struct net *net) 4000 { 4001 return 0; 4002 } 4003 4004 static void xfrm_statistics_fini(struct net *net) 4005 { 4006 } 4007 #endif 4008 4009 static int __net_init xfrm_policy_init(struct net *net) 4010 { 4011 unsigned int hmask, sz; 4012 int dir, err; 4013 4014 if (net_eq(net, &init_net)) { 4015 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4016 sizeof(struct xfrm_dst), 4017 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4018 NULL); 4019 err = rhashtable_init(&xfrm_policy_inexact_table, 4020 &xfrm_pol_inexact_params); 4021 BUG_ON(err); 4022 } 4023 4024 hmask = 8 - 1; 4025 sz = (hmask+1) * sizeof(struct hlist_head); 4026 4027 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4028 if (!net->xfrm.policy_byidx) 4029 goto out_byidx; 4030 net->xfrm.policy_idx_hmask = hmask; 4031 4032 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4033 struct xfrm_policy_hash *htab; 4034 4035 net->xfrm.policy_count[dir] = 0; 4036 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4037 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4038 4039 htab = &net->xfrm.policy_bydst[dir]; 4040 htab->table = xfrm_hash_alloc(sz); 4041 if (!htab->table) 4042 goto out_bydst; 4043 htab->hmask = hmask; 4044 htab->dbits4 = 32; 4045 htab->sbits4 = 32; 4046 htab->dbits6 = 128; 4047 htab->sbits6 = 128; 4048 } 4049 net->xfrm.policy_hthresh.lbits4 = 32; 4050 net->xfrm.policy_hthresh.rbits4 = 32; 4051 net->xfrm.policy_hthresh.lbits6 = 128; 4052 net->xfrm.policy_hthresh.rbits6 = 128; 4053 4054 seqlock_init(&net->xfrm.policy_hthresh.lock); 4055 4056 INIT_LIST_HEAD(&net->xfrm.policy_all); 4057 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4058 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4059 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4060 return 0; 4061 4062 out_bydst: 4063 for (dir--; dir >= 0; dir--) { 4064 struct xfrm_policy_hash *htab; 4065 4066 htab = &net->xfrm.policy_bydst[dir]; 4067 xfrm_hash_free(htab->table, sz); 4068 } 4069 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4070 out_byidx: 4071 return -ENOMEM; 4072 } 4073 4074 static void xfrm_policy_fini(struct net *net) 4075 { 4076 struct xfrm_pol_inexact_bin *b, *t; 4077 unsigned int sz; 4078 int dir; 4079 4080 flush_work(&net->xfrm.policy_hash_work); 4081 #ifdef CONFIG_XFRM_SUB_POLICY 4082 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4083 #endif 4084 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4085 4086 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4087 4088 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4089 struct xfrm_policy_hash *htab; 4090 4091 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4092 4093 htab = &net->xfrm.policy_bydst[dir]; 4094 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4095 WARN_ON(!hlist_empty(htab->table)); 4096 xfrm_hash_free(htab->table, sz); 4097 } 4098 4099 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4100 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4101 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4102 4103 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4104 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4105 __xfrm_policy_inexact_prune_bin(b, true); 4106 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4107 } 4108 4109 static int __net_init xfrm_net_init(struct net *net) 4110 { 4111 int rv; 4112 4113 /* Initialize the per-net locks here */ 4114 spin_lock_init(&net->xfrm.xfrm_state_lock); 4115 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4116 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4117 4118 rv = xfrm_statistics_init(net); 4119 if (rv < 0) 4120 goto out_statistics; 4121 rv = xfrm_state_init(net); 4122 if (rv < 0) 4123 goto out_state; 4124 rv = xfrm_policy_init(net); 4125 if (rv < 0) 4126 goto out_policy; 4127 rv = xfrm_sysctl_init(net); 4128 if (rv < 0) 4129 goto out_sysctl; 4130 4131 return 0; 4132 4133 out_sysctl: 4134 xfrm_policy_fini(net); 4135 out_policy: 4136 xfrm_state_fini(net); 4137 out_state: 4138 xfrm_statistics_fini(net); 4139 out_statistics: 4140 return rv; 4141 } 4142 4143 static void __net_exit xfrm_net_exit(struct net *net) 4144 { 4145 xfrm_sysctl_fini(net); 4146 xfrm_policy_fini(net); 4147 xfrm_state_fini(net); 4148 xfrm_statistics_fini(net); 4149 } 4150 4151 static struct pernet_operations __net_initdata xfrm_net_ops = { 4152 .init = xfrm_net_init, 4153 .exit = xfrm_net_exit, 4154 }; 4155 4156 void __init xfrm_init(void) 4157 { 4158 register_pernet_subsys(&xfrm_net_ops); 4159 xfrm_dev_init(); 4160 seqcount_init(&xfrm_policy_hash_generation); 4161 xfrm_input_init(); 4162 4163 #ifdef CONFIG_INET_ESPINTCP 4164 espintcp_init(); 4165 #endif 4166 4167 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4168 synchronize_rcu(); 4169 } 4170 4171 #ifdef CONFIG_AUDITSYSCALL 4172 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4173 struct audit_buffer *audit_buf) 4174 { 4175 struct xfrm_sec_ctx *ctx = xp->security; 4176 struct xfrm_selector *sel = &xp->selector; 4177 4178 if (ctx) 4179 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4180 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4181 4182 switch (sel->family) { 4183 case AF_INET: 4184 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4185 if (sel->prefixlen_s != 32) 4186 audit_log_format(audit_buf, " src_prefixlen=%d", 4187 sel->prefixlen_s); 4188 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4189 if (sel->prefixlen_d != 32) 4190 audit_log_format(audit_buf, " dst_prefixlen=%d", 4191 sel->prefixlen_d); 4192 break; 4193 case AF_INET6: 4194 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4195 if (sel->prefixlen_s != 128) 4196 audit_log_format(audit_buf, " src_prefixlen=%d", 4197 sel->prefixlen_s); 4198 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4199 if (sel->prefixlen_d != 128) 4200 audit_log_format(audit_buf, " dst_prefixlen=%d", 4201 sel->prefixlen_d); 4202 break; 4203 } 4204 } 4205 4206 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4207 { 4208 struct audit_buffer *audit_buf; 4209 4210 audit_buf = xfrm_audit_start("SPD-add"); 4211 if (audit_buf == NULL) 4212 return; 4213 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4214 audit_log_format(audit_buf, " res=%u", result); 4215 xfrm_audit_common_policyinfo(xp, audit_buf); 4216 audit_log_end(audit_buf); 4217 } 4218 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4219 4220 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4221 bool task_valid) 4222 { 4223 struct audit_buffer *audit_buf; 4224 4225 audit_buf = xfrm_audit_start("SPD-delete"); 4226 if (audit_buf == NULL) 4227 return; 4228 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4229 audit_log_format(audit_buf, " res=%u", result); 4230 xfrm_audit_common_policyinfo(xp, audit_buf); 4231 audit_log_end(audit_buf); 4232 } 4233 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4234 #endif 4235 4236 #ifdef CONFIG_XFRM_MIGRATE 4237 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4238 const struct xfrm_selector *sel_tgt) 4239 { 4240 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4241 if (sel_tgt->family == sel_cmp->family && 4242 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4243 sel_cmp->family) && 4244 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4245 sel_cmp->family) && 4246 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4247 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4248 return true; 4249 } 4250 } else { 4251 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4252 return true; 4253 } 4254 } 4255 return false; 4256 } 4257 4258 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4259 u8 dir, u8 type, struct net *net) 4260 { 4261 struct xfrm_policy *pol, *ret = NULL; 4262 struct hlist_head *chain; 4263 u32 priority = ~0U; 4264 4265 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4266 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4267 hlist_for_each_entry(pol, chain, bydst) { 4268 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4269 pol->type == type) { 4270 ret = pol; 4271 priority = ret->priority; 4272 break; 4273 } 4274 } 4275 chain = &net->xfrm.policy_inexact[dir]; 4276 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4277 if ((pol->priority >= priority) && ret) 4278 break; 4279 4280 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4281 pol->type == type) { 4282 ret = pol; 4283 break; 4284 } 4285 } 4286 4287 xfrm_pol_hold(ret); 4288 4289 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4290 4291 return ret; 4292 } 4293 4294 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4295 { 4296 int match = 0; 4297 4298 if (t->mode == m->mode && t->id.proto == m->proto && 4299 (m->reqid == 0 || t->reqid == m->reqid)) { 4300 switch (t->mode) { 4301 case XFRM_MODE_TUNNEL: 4302 case XFRM_MODE_BEET: 4303 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4304 m->old_family) && 4305 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4306 m->old_family)) { 4307 match = 1; 4308 } 4309 break; 4310 case XFRM_MODE_TRANSPORT: 4311 /* in case of transport mode, template does not store 4312 any IP addresses, hence we just compare mode and 4313 protocol */ 4314 match = 1; 4315 break; 4316 default: 4317 break; 4318 } 4319 } 4320 return match; 4321 } 4322 4323 /* update endpoint address(es) of template(s) */ 4324 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4325 struct xfrm_migrate *m, int num_migrate) 4326 { 4327 struct xfrm_migrate *mp; 4328 int i, j, n = 0; 4329 4330 write_lock_bh(&pol->lock); 4331 if (unlikely(pol->walk.dead)) { 4332 /* target policy has been deleted */ 4333 write_unlock_bh(&pol->lock); 4334 return -ENOENT; 4335 } 4336 4337 for (i = 0; i < pol->xfrm_nr; i++) { 4338 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4339 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4340 continue; 4341 n++; 4342 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4343 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4344 continue; 4345 /* update endpoints */ 4346 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4347 sizeof(pol->xfrm_vec[i].id.daddr)); 4348 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4349 sizeof(pol->xfrm_vec[i].saddr)); 4350 pol->xfrm_vec[i].encap_family = mp->new_family; 4351 /* flush bundles */ 4352 atomic_inc(&pol->genid); 4353 } 4354 } 4355 4356 write_unlock_bh(&pol->lock); 4357 4358 if (!n) 4359 return -ENODATA; 4360 4361 return 0; 4362 } 4363 4364 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4365 { 4366 int i, j; 4367 4368 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4369 return -EINVAL; 4370 4371 for (i = 0; i < num_migrate; i++) { 4372 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4373 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4374 return -EINVAL; 4375 4376 /* check if there is any duplicated entry */ 4377 for (j = i + 1; j < num_migrate; j++) { 4378 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4379 sizeof(m[i].old_daddr)) && 4380 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4381 sizeof(m[i].old_saddr)) && 4382 m[i].proto == m[j].proto && 4383 m[i].mode == m[j].mode && 4384 m[i].reqid == m[j].reqid && 4385 m[i].old_family == m[j].old_family) 4386 return -EINVAL; 4387 } 4388 } 4389 4390 return 0; 4391 } 4392 4393 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4394 struct xfrm_migrate *m, int num_migrate, 4395 struct xfrm_kmaddress *k, struct net *net, 4396 struct xfrm_encap_tmpl *encap) 4397 { 4398 int i, err, nx_cur = 0, nx_new = 0; 4399 struct xfrm_policy *pol = NULL; 4400 struct xfrm_state *x, *xc; 4401 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4402 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4403 struct xfrm_migrate *mp; 4404 4405 /* Stage 0 - sanity checks */ 4406 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4407 goto out; 4408 4409 if (dir >= XFRM_POLICY_MAX) { 4410 err = -EINVAL; 4411 goto out; 4412 } 4413 4414 /* Stage 1 - find policy */ 4415 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4416 err = -ENOENT; 4417 goto out; 4418 } 4419 4420 /* Stage 2 - find and update state(s) */ 4421 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4422 if ((x = xfrm_migrate_state_find(mp, net))) { 4423 x_cur[nx_cur] = x; 4424 nx_cur++; 4425 xc = xfrm_state_migrate(x, mp, encap); 4426 if (xc) { 4427 x_new[nx_new] = xc; 4428 nx_new++; 4429 } else { 4430 err = -ENODATA; 4431 goto restore_state; 4432 } 4433 } 4434 } 4435 4436 /* Stage 3 - update policy */ 4437 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4438 goto restore_state; 4439 4440 /* Stage 4 - delete old state(s) */ 4441 if (nx_cur) { 4442 xfrm_states_put(x_cur, nx_cur); 4443 xfrm_states_delete(x_cur, nx_cur); 4444 } 4445 4446 /* Stage 5 - announce */ 4447 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4448 4449 xfrm_pol_put(pol); 4450 4451 return 0; 4452 out: 4453 return err; 4454 4455 restore_state: 4456 if (pol) 4457 xfrm_pol_put(pol); 4458 if (nx_cur) 4459 xfrm_states_put(x_cur, nx_cur); 4460 if (nx_new) 4461 xfrm_states_delete(x_new, nx_new); 4462 4463 return err; 4464 } 4465 EXPORT_SYMBOL(xfrm_migrate); 4466 #endif 4467