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 43 #include "xfrm_hash.h" 44 45 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 46 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 47 #define XFRM_MAX_QUEUE_LEN 100 48 49 struct xfrm_flo { 50 struct dst_entry *dst_orig; 51 u8 flags; 52 }; 53 54 /* prefixes smaller than this are stored in lists, not trees. */ 55 #define INEXACT_PREFIXLEN_IPV4 16 56 #define INEXACT_PREFIXLEN_IPV6 48 57 58 struct xfrm_pol_inexact_node { 59 struct rb_node node; 60 union { 61 xfrm_address_t addr; 62 struct rcu_head rcu; 63 }; 64 u8 prefixlen; 65 66 struct rb_root root; 67 68 /* the policies matching this node, can be empty list */ 69 struct hlist_head hhead; 70 }; 71 72 /* xfrm inexact policy search tree: 73 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id); 74 * | 75 * +---- root_d: sorted by daddr:prefix 76 * | | 77 * | xfrm_pol_inexact_node 78 * | | 79 * | +- root: sorted by saddr/prefix 80 * | | | 81 * | | xfrm_pol_inexact_node 82 * | | | 83 * | | + root: unused 84 * | | | 85 * | | + hhead: saddr:daddr policies 86 * | | 87 * | +- coarse policies and all any:daddr policies 88 * | 89 * +---- root_s: sorted by saddr:prefix 90 * | | 91 * | xfrm_pol_inexact_node 92 * | | 93 * | + root: unused 94 * | | 95 * | + hhead: saddr:any policies 96 * | 97 * +---- coarse policies and all any:any policies 98 * 99 * Lookups return four candidate lists: 100 * 1. any:any list from top-level xfrm_pol_inexact_bin 101 * 2. any:daddr list from daddr tree 102 * 3. saddr:daddr list from 2nd level daddr tree 103 * 4. saddr:any list from saddr tree 104 * 105 * This result set then needs to be searched for the policy with 106 * the lowest priority. If two results have same prio, youngest one wins. 107 */ 108 109 struct xfrm_pol_inexact_key { 110 possible_net_t net; 111 u32 if_id; 112 u16 family; 113 u8 dir, type; 114 }; 115 116 struct xfrm_pol_inexact_bin { 117 struct xfrm_pol_inexact_key k; 118 struct rhash_head head; 119 /* list containing '*:*' policies */ 120 struct hlist_head hhead; 121 122 seqcount_t count; 123 /* tree sorted by daddr/prefix */ 124 struct rb_root root_d; 125 126 /* tree sorted by saddr/prefix */ 127 struct rb_root root_s; 128 129 /* slow path below */ 130 struct list_head inexact_bins; 131 struct rcu_head rcu; 132 }; 133 134 enum xfrm_pol_inexact_candidate_type { 135 XFRM_POL_CAND_BOTH, 136 XFRM_POL_CAND_SADDR, 137 XFRM_POL_CAND_DADDR, 138 XFRM_POL_CAND_ANY, 139 140 XFRM_POL_CAND_MAX, 141 }; 142 143 struct xfrm_pol_inexact_candidates { 144 struct hlist_head *res[XFRM_POL_CAND_MAX]; 145 }; 146 147 static DEFINE_SPINLOCK(xfrm_if_cb_lock); 148 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 149 150 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 151 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 152 __read_mostly; 153 154 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 155 static __read_mostly seqcount_t xfrm_policy_hash_generation; 156 157 static struct rhashtable xfrm_policy_inexact_table; 158 static const struct rhashtable_params xfrm_pol_inexact_params; 159 160 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 161 static int stale_bundle(struct dst_entry *dst); 162 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 163 static void xfrm_policy_queue_process(struct timer_list *t); 164 165 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 166 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 167 int dir); 168 169 static struct xfrm_pol_inexact_bin * 170 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, 171 u32 if_id); 172 173 static struct xfrm_pol_inexact_bin * 174 xfrm_policy_inexact_lookup_rcu(struct net *net, 175 u8 type, u16 family, u8 dir, u32 if_id); 176 static struct xfrm_policy * 177 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, 178 bool excl); 179 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 180 struct xfrm_policy *policy); 181 182 static bool 183 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 184 struct xfrm_pol_inexact_bin *b, 185 const xfrm_address_t *saddr, 186 const xfrm_address_t *daddr); 187 188 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 189 { 190 return refcount_inc_not_zero(&policy->refcnt); 191 } 192 193 static inline bool 194 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 195 { 196 const struct flowi4 *fl4 = &fl->u.ip4; 197 198 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 199 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 200 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 201 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 202 (fl4->flowi4_proto == sel->proto || !sel->proto) && 203 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 204 } 205 206 static inline bool 207 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 208 { 209 const struct flowi6 *fl6 = &fl->u.ip6; 210 211 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 212 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 213 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 214 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 215 (fl6->flowi6_proto == sel->proto || !sel->proto) && 216 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 217 } 218 219 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 220 unsigned short family) 221 { 222 switch (family) { 223 case AF_INET: 224 return __xfrm4_selector_match(sel, fl); 225 case AF_INET6: 226 return __xfrm6_selector_match(sel, fl); 227 } 228 return false; 229 } 230 231 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 232 { 233 const struct xfrm_policy_afinfo *afinfo; 234 235 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 236 return NULL; 237 rcu_read_lock(); 238 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 239 if (unlikely(!afinfo)) 240 rcu_read_unlock(); 241 return afinfo; 242 } 243 244 /* Called with rcu_read_lock(). */ 245 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 246 { 247 return rcu_dereference(xfrm_if_cb); 248 } 249 250 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 251 const xfrm_address_t *saddr, 252 const xfrm_address_t *daddr, 253 int family, u32 mark) 254 { 255 const struct xfrm_policy_afinfo *afinfo; 256 struct dst_entry *dst; 257 258 afinfo = xfrm_policy_get_afinfo(family); 259 if (unlikely(afinfo == NULL)) 260 return ERR_PTR(-EAFNOSUPPORT); 261 262 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 263 264 rcu_read_unlock(); 265 266 return dst; 267 } 268 EXPORT_SYMBOL(__xfrm_dst_lookup); 269 270 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 271 int tos, int oif, 272 xfrm_address_t *prev_saddr, 273 xfrm_address_t *prev_daddr, 274 int family, u32 mark) 275 { 276 struct net *net = xs_net(x); 277 xfrm_address_t *saddr = &x->props.saddr; 278 xfrm_address_t *daddr = &x->id.daddr; 279 struct dst_entry *dst; 280 281 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 282 saddr = x->coaddr; 283 daddr = prev_daddr; 284 } 285 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 286 saddr = prev_saddr; 287 daddr = x->coaddr; 288 } 289 290 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 291 292 if (!IS_ERR(dst)) { 293 if (prev_saddr != saddr) 294 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 295 if (prev_daddr != daddr) 296 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 297 } 298 299 return dst; 300 } 301 302 static inline unsigned long make_jiffies(long secs) 303 { 304 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 305 return MAX_SCHEDULE_TIMEOUT-1; 306 else 307 return secs*HZ; 308 } 309 310 static void xfrm_policy_timer(struct timer_list *t) 311 { 312 struct xfrm_policy *xp = from_timer(xp, t, timer); 313 time64_t now = ktime_get_real_seconds(); 314 time64_t next = TIME64_MAX; 315 int warn = 0; 316 int dir; 317 318 read_lock(&xp->lock); 319 320 if (unlikely(xp->walk.dead)) 321 goto out; 322 323 dir = xfrm_policy_id2dir(xp->index); 324 325 if (xp->lft.hard_add_expires_seconds) { 326 time64_t tmo = xp->lft.hard_add_expires_seconds + 327 xp->curlft.add_time - now; 328 if (tmo <= 0) 329 goto expired; 330 if (tmo < next) 331 next = tmo; 332 } 333 if (xp->lft.hard_use_expires_seconds) { 334 time64_t tmo = xp->lft.hard_use_expires_seconds + 335 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 336 if (tmo <= 0) 337 goto expired; 338 if (tmo < next) 339 next = tmo; 340 } 341 if (xp->lft.soft_add_expires_seconds) { 342 time64_t tmo = xp->lft.soft_add_expires_seconds + 343 xp->curlft.add_time - now; 344 if (tmo <= 0) { 345 warn = 1; 346 tmo = XFRM_KM_TIMEOUT; 347 } 348 if (tmo < next) 349 next = tmo; 350 } 351 if (xp->lft.soft_use_expires_seconds) { 352 time64_t tmo = xp->lft.soft_use_expires_seconds + 353 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 354 if (tmo <= 0) { 355 warn = 1; 356 tmo = XFRM_KM_TIMEOUT; 357 } 358 if (tmo < next) 359 next = tmo; 360 } 361 362 if (warn) 363 km_policy_expired(xp, dir, 0, 0); 364 if (next != TIME64_MAX && 365 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 366 xfrm_pol_hold(xp); 367 368 out: 369 read_unlock(&xp->lock); 370 xfrm_pol_put(xp); 371 return; 372 373 expired: 374 read_unlock(&xp->lock); 375 if (!xfrm_policy_delete(xp, dir)) 376 km_policy_expired(xp, dir, 1, 0); 377 xfrm_pol_put(xp); 378 } 379 380 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 381 * SPD calls. 382 */ 383 384 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 385 { 386 struct xfrm_policy *policy; 387 388 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 389 390 if (policy) { 391 write_pnet(&policy->xp_net, net); 392 INIT_LIST_HEAD(&policy->walk.all); 393 INIT_HLIST_NODE(&policy->bydst_inexact_list); 394 INIT_HLIST_NODE(&policy->bydst); 395 INIT_HLIST_NODE(&policy->byidx); 396 rwlock_init(&policy->lock); 397 refcount_set(&policy->refcnt, 1); 398 skb_queue_head_init(&policy->polq.hold_queue); 399 timer_setup(&policy->timer, xfrm_policy_timer, 0); 400 timer_setup(&policy->polq.hold_timer, 401 xfrm_policy_queue_process, 0); 402 } 403 return policy; 404 } 405 EXPORT_SYMBOL(xfrm_policy_alloc); 406 407 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 408 { 409 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 410 411 security_xfrm_policy_free(policy->security); 412 kfree(policy); 413 } 414 415 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 416 417 void xfrm_policy_destroy(struct xfrm_policy *policy) 418 { 419 BUG_ON(!policy->walk.dead); 420 421 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 422 BUG(); 423 424 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 425 } 426 EXPORT_SYMBOL(xfrm_policy_destroy); 427 428 /* Rule must be locked. Release descendant resources, announce 429 * entry dead. The rule must be unlinked from lists to the moment. 430 */ 431 432 static void xfrm_policy_kill(struct xfrm_policy *policy) 433 { 434 policy->walk.dead = 1; 435 436 atomic_inc(&policy->genid); 437 438 if (del_timer(&policy->polq.hold_timer)) 439 xfrm_pol_put(policy); 440 skb_queue_purge(&policy->polq.hold_queue); 441 442 if (del_timer(&policy->timer)) 443 xfrm_pol_put(policy); 444 445 xfrm_pol_put(policy); 446 } 447 448 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 449 450 static inline unsigned int idx_hash(struct net *net, u32 index) 451 { 452 return __idx_hash(index, net->xfrm.policy_idx_hmask); 453 } 454 455 /* calculate policy hash thresholds */ 456 static void __get_hash_thresh(struct net *net, 457 unsigned short family, int dir, 458 u8 *dbits, u8 *sbits) 459 { 460 switch (family) { 461 case AF_INET: 462 *dbits = net->xfrm.policy_bydst[dir].dbits4; 463 *sbits = net->xfrm.policy_bydst[dir].sbits4; 464 break; 465 466 case AF_INET6: 467 *dbits = net->xfrm.policy_bydst[dir].dbits6; 468 *sbits = net->xfrm.policy_bydst[dir].sbits6; 469 break; 470 471 default: 472 *dbits = 0; 473 *sbits = 0; 474 } 475 } 476 477 static struct hlist_head *policy_hash_bysel(struct net *net, 478 const struct xfrm_selector *sel, 479 unsigned short family, int dir) 480 { 481 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 482 unsigned int hash; 483 u8 dbits; 484 u8 sbits; 485 486 __get_hash_thresh(net, family, dir, &dbits, &sbits); 487 hash = __sel_hash(sel, family, hmask, dbits, sbits); 488 489 if (hash == hmask + 1) 490 return NULL; 491 492 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 493 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 494 } 495 496 static struct hlist_head *policy_hash_direct(struct net *net, 497 const xfrm_address_t *daddr, 498 const xfrm_address_t *saddr, 499 unsigned short family, int dir) 500 { 501 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 502 unsigned int hash; 503 u8 dbits; 504 u8 sbits; 505 506 __get_hash_thresh(net, family, dir, &dbits, &sbits); 507 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 508 509 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 510 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 511 } 512 513 static void xfrm_dst_hash_transfer(struct net *net, 514 struct hlist_head *list, 515 struct hlist_head *ndsttable, 516 unsigned int nhashmask, 517 int dir) 518 { 519 struct hlist_node *tmp, *entry0 = NULL; 520 struct xfrm_policy *pol; 521 unsigned int h0 = 0; 522 u8 dbits; 523 u8 sbits; 524 525 redo: 526 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 527 unsigned int h; 528 529 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 530 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 531 pol->family, nhashmask, dbits, sbits); 532 if (!entry0) { 533 hlist_del_rcu(&pol->bydst); 534 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 535 h0 = h; 536 } else { 537 if (h != h0) 538 continue; 539 hlist_del_rcu(&pol->bydst); 540 hlist_add_behind_rcu(&pol->bydst, entry0); 541 } 542 entry0 = &pol->bydst; 543 } 544 if (!hlist_empty(list)) { 545 entry0 = NULL; 546 goto redo; 547 } 548 } 549 550 static void xfrm_idx_hash_transfer(struct hlist_head *list, 551 struct hlist_head *nidxtable, 552 unsigned int nhashmask) 553 { 554 struct hlist_node *tmp; 555 struct xfrm_policy *pol; 556 557 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 558 unsigned int h; 559 560 h = __idx_hash(pol->index, nhashmask); 561 hlist_add_head(&pol->byidx, nidxtable+h); 562 } 563 } 564 565 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 566 { 567 return ((old_hmask + 1) << 1) - 1; 568 } 569 570 static void xfrm_bydst_resize(struct net *net, int dir) 571 { 572 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 573 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 574 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 575 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 576 struct hlist_head *odst; 577 int i; 578 579 if (!ndst) 580 return; 581 582 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 583 write_seqcount_begin(&xfrm_policy_hash_generation); 584 585 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 586 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 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 struct xfrm_policy *tmp; 919 920 hlist_for_each_entry(tmp, &n->hhead, bydst) { 921 tmp->bydst_reinsert = true; 922 hlist_del_rcu(&tmp->bydst); 923 } 924 925 xfrm_policy_inexact_list_reinsert(net, node, family); 926 927 if (node->prefixlen == n->prefixlen) { 928 kfree_rcu(n, rcu); 929 return; 930 } 931 932 rb_erase(*p, new); 933 kfree_rcu(n, rcu); 934 n = node; 935 n->prefixlen = prefixlen; 936 goto restart; 937 } 938 } 939 940 rb_link_node_rcu(&n->node, parent, p); 941 rb_insert_color(&n->node, new); 942 } 943 944 /* merge nodes v and n */ 945 static void xfrm_policy_inexact_node_merge(struct net *net, 946 struct xfrm_pol_inexact_node *v, 947 struct xfrm_pol_inexact_node *n, 948 u16 family) 949 { 950 struct xfrm_pol_inexact_node *node; 951 struct xfrm_policy *tmp; 952 struct rb_node *rnode; 953 954 /* To-be-merged node v has a subtree. 955 * 956 * Dismantle it and insert its nodes to n->root. 957 */ 958 while ((rnode = rb_first(&v->root)) != NULL) { 959 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 960 rb_erase(&node->node, &v->root); 961 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 962 family); 963 } 964 965 hlist_for_each_entry(tmp, &v->hhead, bydst) { 966 tmp->bydst_reinsert = true; 967 hlist_del_rcu(&tmp->bydst); 968 } 969 970 xfrm_policy_inexact_list_reinsert(net, n, family); 971 } 972 973 static struct xfrm_pol_inexact_node * 974 xfrm_policy_inexact_insert_node(struct net *net, 975 struct rb_root *root, 976 xfrm_address_t *addr, 977 u16 family, u8 prefixlen, u8 dir) 978 { 979 struct xfrm_pol_inexact_node *cached = NULL; 980 struct rb_node **p, *parent = NULL; 981 struct xfrm_pol_inexact_node *node; 982 983 p = &root->rb_node; 984 while (*p) { 985 int delta; 986 987 parent = *p; 988 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 989 990 delta = xfrm_policy_addr_delta(addr, &node->addr, 991 node->prefixlen, 992 family); 993 if (delta == 0 && prefixlen >= node->prefixlen) { 994 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 995 return node; 996 } 997 998 if (delta < 0) 999 p = &parent->rb_left; 1000 else 1001 p = &parent->rb_right; 1002 1003 if (prefixlen < node->prefixlen) { 1004 delta = xfrm_policy_addr_delta(addr, &node->addr, 1005 prefixlen, 1006 family); 1007 if (delta) 1008 continue; 1009 1010 /* This node is a subnet of the new prefix. It needs 1011 * to be removed and re-inserted with the smaller 1012 * prefix and all nodes that are now also covered 1013 * by the reduced prefixlen. 1014 */ 1015 rb_erase(&node->node, root); 1016 1017 if (!cached) { 1018 xfrm_pol_inexact_node_init(node, addr, 1019 prefixlen); 1020 cached = node; 1021 } else { 1022 /* This node also falls within the new 1023 * prefixlen. Merge the to-be-reinserted 1024 * node and this one. 1025 */ 1026 xfrm_policy_inexact_node_merge(net, node, 1027 cached, family); 1028 kfree_rcu(node, rcu); 1029 } 1030 1031 /* restart */ 1032 p = &root->rb_node; 1033 parent = NULL; 1034 } 1035 } 1036 1037 node = cached; 1038 if (!node) { 1039 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1040 if (!node) 1041 return NULL; 1042 } 1043 1044 rb_link_node_rcu(&node->node, parent, p); 1045 rb_insert_color(&node->node, root); 1046 1047 return node; 1048 } 1049 1050 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1051 { 1052 struct xfrm_pol_inexact_node *node; 1053 struct rb_node *rn = rb_first(r); 1054 1055 while (rn) { 1056 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1057 1058 xfrm_policy_inexact_gc_tree(&node->root, rm); 1059 rn = rb_next(rn); 1060 1061 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1062 WARN_ON_ONCE(rm); 1063 continue; 1064 } 1065 1066 rb_erase(&node->node, r); 1067 kfree_rcu(node, rcu); 1068 } 1069 } 1070 1071 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1072 { 1073 write_seqcount_begin(&b->count); 1074 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1075 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1076 write_seqcount_end(&b->count); 1077 1078 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1079 !hlist_empty(&b->hhead)) { 1080 WARN_ON_ONCE(net_exit); 1081 return; 1082 } 1083 1084 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1085 xfrm_pol_inexact_params) == 0) { 1086 list_del(&b->inexact_bins); 1087 kfree_rcu(b, rcu); 1088 } 1089 } 1090 1091 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1092 { 1093 struct net *net = read_pnet(&b->k.net); 1094 1095 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1096 __xfrm_policy_inexact_prune_bin(b, false); 1097 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1098 } 1099 1100 static void __xfrm_policy_inexact_flush(struct net *net) 1101 { 1102 struct xfrm_pol_inexact_bin *bin, *t; 1103 1104 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1105 1106 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1107 __xfrm_policy_inexact_prune_bin(bin, false); 1108 } 1109 1110 static struct hlist_head * 1111 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1112 struct xfrm_policy *policy, u8 dir) 1113 { 1114 struct xfrm_pol_inexact_node *n; 1115 struct net *net; 1116 1117 net = xp_net(policy); 1118 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1119 1120 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1121 return &bin->hhead; 1122 1123 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1124 policy->family, 1125 policy->selector.prefixlen_d)) { 1126 write_seqcount_begin(&bin->count); 1127 n = xfrm_policy_inexact_insert_node(net, 1128 &bin->root_s, 1129 &policy->selector.saddr, 1130 policy->family, 1131 policy->selector.prefixlen_s, 1132 dir); 1133 write_seqcount_end(&bin->count); 1134 if (!n) 1135 return NULL; 1136 1137 return &n->hhead; 1138 } 1139 1140 /* daddr is fixed */ 1141 write_seqcount_begin(&bin->count); 1142 n = xfrm_policy_inexact_insert_node(net, 1143 &bin->root_d, 1144 &policy->selector.daddr, 1145 policy->family, 1146 policy->selector.prefixlen_d, dir); 1147 write_seqcount_end(&bin->count); 1148 if (!n) 1149 return NULL; 1150 1151 /* saddr is wildcard */ 1152 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1153 policy->family, 1154 policy->selector.prefixlen_s)) 1155 return &n->hhead; 1156 1157 write_seqcount_begin(&bin->count); 1158 n = xfrm_policy_inexact_insert_node(net, 1159 &n->root, 1160 &policy->selector.saddr, 1161 policy->family, 1162 policy->selector.prefixlen_s, dir); 1163 write_seqcount_end(&bin->count); 1164 if (!n) 1165 return NULL; 1166 1167 return &n->hhead; 1168 } 1169 1170 static struct xfrm_policy * 1171 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1172 { 1173 struct xfrm_pol_inexact_bin *bin; 1174 struct xfrm_policy *delpol; 1175 struct hlist_head *chain; 1176 struct net *net; 1177 1178 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1179 if (!bin) 1180 return ERR_PTR(-ENOMEM); 1181 1182 net = xp_net(policy); 1183 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1184 1185 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1186 if (!chain) { 1187 __xfrm_policy_inexact_prune_bin(bin, false); 1188 return ERR_PTR(-ENOMEM); 1189 } 1190 1191 delpol = xfrm_policy_insert_list(chain, policy, excl); 1192 if (delpol && excl) { 1193 __xfrm_policy_inexact_prune_bin(bin, false); 1194 return ERR_PTR(-EEXIST); 1195 } 1196 1197 chain = &net->xfrm.policy_inexact[dir]; 1198 xfrm_policy_insert_inexact_list(chain, policy); 1199 1200 if (delpol) 1201 __xfrm_policy_inexact_prune_bin(bin, false); 1202 1203 return delpol; 1204 } 1205 1206 static void xfrm_hash_rebuild(struct work_struct *work) 1207 { 1208 struct net *net = container_of(work, struct net, 1209 xfrm.policy_hthresh.work); 1210 unsigned int hmask; 1211 struct xfrm_policy *pol; 1212 struct xfrm_policy *policy; 1213 struct hlist_head *chain; 1214 struct hlist_head *odst; 1215 struct hlist_node *newpos; 1216 int i; 1217 int dir; 1218 unsigned seq; 1219 u8 lbits4, rbits4, lbits6, rbits6; 1220 1221 mutex_lock(&hash_resize_mutex); 1222 1223 /* read selector prefixlen thresholds */ 1224 do { 1225 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1226 1227 lbits4 = net->xfrm.policy_hthresh.lbits4; 1228 rbits4 = net->xfrm.policy_hthresh.rbits4; 1229 lbits6 = net->xfrm.policy_hthresh.lbits6; 1230 rbits6 = net->xfrm.policy_hthresh.rbits6; 1231 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1232 1233 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1234 write_seqcount_begin(&xfrm_policy_hash_generation); 1235 1236 /* make sure that we can insert the indirect policies again before 1237 * we start with destructive action. 1238 */ 1239 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1240 struct xfrm_pol_inexact_bin *bin; 1241 u8 dbits, sbits; 1242 1243 dir = xfrm_policy_id2dir(policy->index); 1244 if (policy->walk.dead || dir >= XFRM_POLICY_MAX) 1245 continue; 1246 1247 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1248 if (policy->family == AF_INET) { 1249 dbits = rbits4; 1250 sbits = lbits4; 1251 } else { 1252 dbits = rbits6; 1253 sbits = lbits6; 1254 } 1255 } else { 1256 if (policy->family == AF_INET) { 1257 dbits = lbits4; 1258 sbits = rbits4; 1259 } else { 1260 dbits = lbits6; 1261 sbits = rbits6; 1262 } 1263 } 1264 1265 if (policy->selector.prefixlen_d < dbits || 1266 policy->selector.prefixlen_s < sbits) 1267 continue; 1268 1269 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1270 if (!bin) 1271 goto out_unlock; 1272 1273 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1274 goto out_unlock; 1275 } 1276 1277 /* reset the bydst and inexact table in all directions */ 1278 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1279 struct hlist_node *n; 1280 1281 hlist_for_each_entry_safe(policy, n, 1282 &net->xfrm.policy_inexact[dir], 1283 bydst_inexact_list) 1284 hlist_del_init(&policy->bydst_inexact_list); 1285 1286 hmask = net->xfrm.policy_bydst[dir].hmask; 1287 odst = net->xfrm.policy_bydst[dir].table; 1288 for (i = hmask; i >= 0; i--) 1289 INIT_HLIST_HEAD(odst + i); 1290 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1291 /* dir out => dst = remote, src = local */ 1292 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1293 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1294 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1295 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1296 } else { 1297 /* dir in/fwd => dst = local, src = remote */ 1298 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1299 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1300 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1301 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1302 } 1303 } 1304 1305 /* re-insert all policies by order of creation */ 1306 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1307 if (policy->walk.dead) 1308 continue; 1309 dir = xfrm_policy_id2dir(policy->index); 1310 if (dir >= XFRM_POLICY_MAX) { 1311 /* skip socket policies */ 1312 continue; 1313 } 1314 newpos = NULL; 1315 chain = policy_hash_bysel(net, &policy->selector, 1316 policy->family, dir); 1317 1318 hlist_del_rcu(&policy->bydst); 1319 1320 if (!chain) { 1321 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1322 1323 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1324 continue; 1325 } 1326 1327 hlist_for_each_entry(pol, chain, bydst) { 1328 if (policy->priority >= pol->priority) 1329 newpos = &pol->bydst; 1330 else 1331 break; 1332 } 1333 if (newpos) 1334 hlist_add_behind_rcu(&policy->bydst, newpos); 1335 else 1336 hlist_add_head_rcu(&policy->bydst, chain); 1337 } 1338 1339 out_unlock: 1340 __xfrm_policy_inexact_flush(net); 1341 write_seqcount_end(&xfrm_policy_hash_generation); 1342 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1343 1344 mutex_unlock(&hash_resize_mutex); 1345 } 1346 1347 void xfrm_policy_hash_rebuild(struct net *net) 1348 { 1349 schedule_work(&net->xfrm.policy_hthresh.work); 1350 } 1351 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1352 1353 /* Generate new index... KAME seems to generate them ordered by cost 1354 * of an absolute inpredictability of ordering of rules. This will not pass. */ 1355 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1356 { 1357 static u32 idx_generator; 1358 1359 for (;;) { 1360 struct hlist_head *list; 1361 struct xfrm_policy *p; 1362 u32 idx; 1363 int found; 1364 1365 if (!index) { 1366 idx = (idx_generator | dir); 1367 idx_generator += 8; 1368 } else { 1369 idx = index; 1370 index = 0; 1371 } 1372 1373 if (idx == 0) 1374 idx = 8; 1375 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1376 found = 0; 1377 hlist_for_each_entry(p, list, byidx) { 1378 if (p->index == idx) { 1379 found = 1; 1380 break; 1381 } 1382 } 1383 if (!found) 1384 return idx; 1385 } 1386 } 1387 1388 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1389 { 1390 u32 *p1 = (u32 *) s1; 1391 u32 *p2 = (u32 *) s2; 1392 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1393 int i; 1394 1395 for (i = 0; i < len; i++) { 1396 if (p1[i] != p2[i]) 1397 return 1; 1398 } 1399 1400 return 0; 1401 } 1402 1403 static void xfrm_policy_requeue(struct xfrm_policy *old, 1404 struct xfrm_policy *new) 1405 { 1406 struct xfrm_policy_queue *pq = &old->polq; 1407 struct sk_buff_head list; 1408 1409 if (skb_queue_empty(&pq->hold_queue)) 1410 return; 1411 1412 __skb_queue_head_init(&list); 1413 1414 spin_lock_bh(&pq->hold_queue.lock); 1415 skb_queue_splice_init(&pq->hold_queue, &list); 1416 if (del_timer(&pq->hold_timer)) 1417 xfrm_pol_put(old); 1418 spin_unlock_bh(&pq->hold_queue.lock); 1419 1420 pq = &new->polq; 1421 1422 spin_lock_bh(&pq->hold_queue.lock); 1423 skb_queue_splice(&list, &pq->hold_queue); 1424 pq->timeout = XFRM_QUEUE_TMO_MIN; 1425 if (!mod_timer(&pq->hold_timer, jiffies)) 1426 xfrm_pol_hold(new); 1427 spin_unlock_bh(&pq->hold_queue.lock); 1428 } 1429 1430 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 1431 struct xfrm_policy *pol) 1432 { 1433 u32 mark = policy->mark.v & policy->mark.m; 1434 1435 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 1436 return true; 1437 1438 if ((mark & pol->mark.m) == pol->mark.v && 1439 policy->priority == pol->priority) 1440 return true; 1441 1442 return false; 1443 } 1444 1445 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1446 { 1447 const struct xfrm_pol_inexact_key *k = data; 1448 u32 a = k->type << 24 | k->dir << 16 | k->family; 1449 1450 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1451 seed); 1452 } 1453 1454 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1455 { 1456 const struct xfrm_pol_inexact_bin *b = data; 1457 1458 return xfrm_pol_bin_key(&b->k, 0, seed); 1459 } 1460 1461 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1462 const void *ptr) 1463 { 1464 const struct xfrm_pol_inexact_key *key = arg->key; 1465 const struct xfrm_pol_inexact_bin *b = ptr; 1466 int ret; 1467 1468 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1469 return -1; 1470 1471 ret = b->k.dir ^ key->dir; 1472 if (ret) 1473 return ret; 1474 1475 ret = b->k.type ^ key->type; 1476 if (ret) 1477 return ret; 1478 1479 ret = b->k.family ^ key->family; 1480 if (ret) 1481 return ret; 1482 1483 return b->k.if_id ^ key->if_id; 1484 } 1485 1486 static const struct rhashtable_params xfrm_pol_inexact_params = { 1487 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1488 .hashfn = xfrm_pol_bin_key, 1489 .obj_hashfn = xfrm_pol_bin_obj, 1490 .obj_cmpfn = xfrm_pol_bin_cmp, 1491 .automatic_shrinking = true, 1492 }; 1493 1494 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain, 1495 struct xfrm_policy *policy) 1496 { 1497 struct xfrm_policy *pol, *delpol = NULL; 1498 struct hlist_node *newpos = NULL; 1499 int i = 0; 1500 1501 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1502 if (pol->type == policy->type && 1503 pol->if_id == policy->if_id && 1504 !selector_cmp(&pol->selector, &policy->selector) && 1505 xfrm_policy_mark_match(policy, pol) && 1506 xfrm_sec_ctx_match(pol->security, policy->security) && 1507 !WARN_ON(delpol)) { 1508 delpol = pol; 1509 if (policy->priority > pol->priority) 1510 continue; 1511 } else if (policy->priority >= pol->priority) { 1512 newpos = &pol->bydst_inexact_list; 1513 continue; 1514 } 1515 if (delpol) 1516 break; 1517 } 1518 1519 if (newpos) 1520 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); 1521 else 1522 hlist_add_head_rcu(&policy->bydst_inexact_list, chain); 1523 1524 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 1525 pol->pos = i; 1526 i++; 1527 } 1528 } 1529 1530 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain, 1531 struct xfrm_policy *policy, 1532 bool excl) 1533 { 1534 struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL; 1535 1536 hlist_for_each_entry(pol, chain, bydst) { 1537 if (pol->type == policy->type && 1538 pol->if_id == policy->if_id && 1539 !selector_cmp(&pol->selector, &policy->selector) && 1540 xfrm_policy_mark_match(policy, pol) && 1541 xfrm_sec_ctx_match(pol->security, policy->security) && 1542 !WARN_ON(delpol)) { 1543 if (excl) 1544 return ERR_PTR(-EEXIST); 1545 delpol = pol; 1546 if (policy->priority > pol->priority) 1547 continue; 1548 } else if (policy->priority >= pol->priority) { 1549 newpos = pol; 1550 continue; 1551 } 1552 if (delpol) 1553 break; 1554 } 1555 1556 if (newpos) 1557 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1558 else 1559 hlist_add_head_rcu(&policy->bydst, chain); 1560 1561 return delpol; 1562 } 1563 1564 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1565 { 1566 struct net *net = xp_net(policy); 1567 struct xfrm_policy *delpol; 1568 struct hlist_head *chain; 1569 1570 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1571 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1572 if (chain) 1573 delpol = xfrm_policy_insert_list(chain, policy, excl); 1574 else 1575 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1576 1577 if (IS_ERR(delpol)) { 1578 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1579 return PTR_ERR(delpol); 1580 } 1581 1582 __xfrm_policy_link(policy, dir); 1583 1584 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1585 if (policy->family == AF_INET) 1586 rt_genid_bump_ipv4(net); 1587 else 1588 rt_genid_bump_ipv6(net); 1589 1590 if (delpol) { 1591 xfrm_policy_requeue(delpol, policy); 1592 __xfrm_policy_unlink(delpol, dir); 1593 } 1594 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1595 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1596 policy->curlft.add_time = ktime_get_real_seconds(); 1597 policy->curlft.use_time = 0; 1598 if (!mod_timer(&policy->timer, jiffies + HZ)) 1599 xfrm_pol_hold(policy); 1600 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1601 1602 if (delpol) 1603 xfrm_policy_kill(delpol); 1604 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1605 schedule_work(&net->xfrm.policy_hash_work); 1606 1607 return 0; 1608 } 1609 EXPORT_SYMBOL(xfrm_policy_insert); 1610 1611 static struct xfrm_policy * 1612 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id, 1613 u8 type, int dir, 1614 struct xfrm_selector *sel, 1615 struct xfrm_sec_ctx *ctx) 1616 { 1617 struct xfrm_policy *pol; 1618 1619 if (!chain) 1620 return NULL; 1621 1622 hlist_for_each_entry(pol, chain, bydst) { 1623 if (pol->type == type && 1624 pol->if_id == if_id && 1625 (mark & pol->mark.m) == pol->mark.v && 1626 !selector_cmp(sel, &pol->selector) && 1627 xfrm_sec_ctx_match(ctx, pol->security)) 1628 return pol; 1629 } 1630 1631 return NULL; 1632 } 1633 1634 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id, 1635 u8 type, int dir, 1636 struct xfrm_selector *sel, 1637 struct xfrm_sec_ctx *ctx, int delete, 1638 int *err) 1639 { 1640 struct xfrm_pol_inexact_bin *bin = NULL; 1641 struct xfrm_policy *pol, *ret = NULL; 1642 struct hlist_head *chain; 1643 1644 *err = 0; 1645 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1646 chain = policy_hash_bysel(net, sel, sel->family, dir); 1647 if (!chain) { 1648 struct xfrm_pol_inexact_candidates cand; 1649 int i; 1650 1651 bin = xfrm_policy_inexact_lookup(net, type, 1652 sel->family, dir, if_id); 1653 if (!bin) { 1654 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1655 return NULL; 1656 } 1657 1658 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1659 &sel->saddr, 1660 &sel->daddr)) { 1661 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1662 return NULL; 1663 } 1664 1665 pol = NULL; 1666 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1667 struct xfrm_policy *tmp; 1668 1669 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1670 if_id, type, dir, 1671 sel, ctx); 1672 if (!tmp) 1673 continue; 1674 1675 if (!pol || tmp->pos < pol->pos) 1676 pol = tmp; 1677 } 1678 } else { 1679 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1680 sel, ctx); 1681 } 1682 1683 if (pol) { 1684 xfrm_pol_hold(pol); 1685 if (delete) { 1686 *err = security_xfrm_policy_delete(pol->security); 1687 if (*err) { 1688 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1689 return pol; 1690 } 1691 __xfrm_policy_unlink(pol, dir); 1692 } 1693 ret = pol; 1694 } 1695 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1696 1697 if (ret && delete) 1698 xfrm_policy_kill(ret); 1699 if (bin && delete) 1700 xfrm_policy_inexact_prune_bin(bin); 1701 return ret; 1702 } 1703 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1704 1705 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id, 1706 u8 type, int dir, u32 id, int delete, 1707 int *err) 1708 { 1709 struct xfrm_policy *pol, *ret; 1710 struct hlist_head *chain; 1711 1712 *err = -ENOENT; 1713 if (xfrm_policy_id2dir(id) != dir) 1714 return NULL; 1715 1716 *err = 0; 1717 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1718 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1719 ret = NULL; 1720 hlist_for_each_entry(pol, chain, byidx) { 1721 if (pol->type == type && pol->index == id && 1722 pol->if_id == if_id && 1723 (mark & pol->mark.m) == pol->mark.v) { 1724 xfrm_pol_hold(pol); 1725 if (delete) { 1726 *err = security_xfrm_policy_delete( 1727 pol->security); 1728 if (*err) { 1729 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1730 return pol; 1731 } 1732 __xfrm_policy_unlink(pol, dir); 1733 } 1734 ret = pol; 1735 break; 1736 } 1737 } 1738 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1739 1740 if (ret && delete) 1741 xfrm_policy_kill(ret); 1742 return ret; 1743 } 1744 EXPORT_SYMBOL(xfrm_policy_byid); 1745 1746 #ifdef CONFIG_SECURITY_NETWORK_XFRM 1747 static inline int 1748 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1749 { 1750 struct xfrm_policy *pol; 1751 int err = 0; 1752 1753 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1754 if (pol->walk.dead || 1755 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1756 pol->type != type) 1757 continue; 1758 1759 err = security_xfrm_policy_delete(pol->security); 1760 if (err) { 1761 xfrm_audit_policy_delete(pol, 0, task_valid); 1762 return err; 1763 } 1764 } 1765 return err; 1766 } 1767 #else 1768 static inline int 1769 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1770 { 1771 return 0; 1772 } 1773 #endif 1774 1775 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1776 { 1777 int dir, err = 0, cnt = 0; 1778 struct xfrm_policy *pol; 1779 1780 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1781 1782 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1783 if (err) 1784 goto out; 1785 1786 again: 1787 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1788 dir = xfrm_policy_id2dir(pol->index); 1789 if (pol->walk.dead || 1790 dir >= XFRM_POLICY_MAX || 1791 pol->type != type) 1792 continue; 1793 1794 __xfrm_policy_unlink(pol, dir); 1795 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1796 cnt++; 1797 xfrm_audit_policy_delete(pol, 1, task_valid); 1798 xfrm_policy_kill(pol); 1799 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1800 goto again; 1801 } 1802 if (cnt) 1803 __xfrm_policy_inexact_flush(net); 1804 else 1805 err = -ESRCH; 1806 out: 1807 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1808 return err; 1809 } 1810 EXPORT_SYMBOL(xfrm_policy_flush); 1811 1812 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1813 int (*func)(struct xfrm_policy *, int, int, void*), 1814 void *data) 1815 { 1816 struct xfrm_policy *pol; 1817 struct xfrm_policy_walk_entry *x; 1818 int error = 0; 1819 1820 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1821 walk->type != XFRM_POLICY_TYPE_ANY) 1822 return -EINVAL; 1823 1824 if (list_empty(&walk->walk.all) && walk->seq != 0) 1825 return 0; 1826 1827 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1828 if (list_empty(&walk->walk.all)) 1829 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1830 else 1831 x = list_first_entry(&walk->walk.all, 1832 struct xfrm_policy_walk_entry, all); 1833 1834 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1835 if (x->dead) 1836 continue; 1837 pol = container_of(x, struct xfrm_policy, walk); 1838 if (walk->type != XFRM_POLICY_TYPE_ANY && 1839 walk->type != pol->type) 1840 continue; 1841 error = func(pol, xfrm_policy_id2dir(pol->index), 1842 walk->seq, data); 1843 if (error) { 1844 list_move_tail(&walk->walk.all, &x->all); 1845 goto out; 1846 } 1847 walk->seq++; 1848 } 1849 if (walk->seq == 0) { 1850 error = -ENOENT; 1851 goto out; 1852 } 1853 list_del_init(&walk->walk.all); 1854 out: 1855 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1856 return error; 1857 } 1858 EXPORT_SYMBOL(xfrm_policy_walk); 1859 1860 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1861 { 1862 INIT_LIST_HEAD(&walk->walk.all); 1863 walk->walk.dead = 1; 1864 walk->type = type; 1865 walk->seq = 0; 1866 } 1867 EXPORT_SYMBOL(xfrm_policy_walk_init); 1868 1869 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1870 { 1871 if (list_empty(&walk->walk.all)) 1872 return; 1873 1874 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1875 list_del(&walk->walk.all); 1876 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1877 } 1878 EXPORT_SYMBOL(xfrm_policy_walk_done); 1879 1880 /* 1881 * Find policy to apply to this flow. 1882 * 1883 * Returns 0 if policy found, else an -errno. 1884 */ 1885 static int xfrm_policy_match(const struct xfrm_policy *pol, 1886 const struct flowi *fl, 1887 u8 type, u16 family, int dir, u32 if_id) 1888 { 1889 const struct xfrm_selector *sel = &pol->selector; 1890 int ret = -ESRCH; 1891 bool match; 1892 1893 if (pol->family != family || 1894 pol->if_id != if_id || 1895 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1896 pol->type != type) 1897 return ret; 1898 1899 match = xfrm_selector_match(sel, fl, family); 1900 if (match) 1901 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1902 dir); 1903 return ret; 1904 } 1905 1906 static struct xfrm_pol_inexact_node * 1907 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1908 seqcount_t *count, 1909 const xfrm_address_t *addr, u16 family) 1910 { 1911 const struct rb_node *parent; 1912 int seq; 1913 1914 again: 1915 seq = read_seqcount_begin(count); 1916 1917 parent = rcu_dereference_raw(r->rb_node); 1918 while (parent) { 1919 struct xfrm_pol_inexact_node *node; 1920 int delta; 1921 1922 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1923 1924 delta = xfrm_policy_addr_delta(addr, &node->addr, 1925 node->prefixlen, family); 1926 if (delta < 0) { 1927 parent = rcu_dereference_raw(parent->rb_left); 1928 continue; 1929 } else if (delta > 0) { 1930 parent = rcu_dereference_raw(parent->rb_right); 1931 continue; 1932 } 1933 1934 return node; 1935 } 1936 1937 if (read_seqcount_retry(count, seq)) 1938 goto again; 1939 1940 return NULL; 1941 } 1942 1943 static bool 1944 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 1945 struct xfrm_pol_inexact_bin *b, 1946 const xfrm_address_t *saddr, 1947 const xfrm_address_t *daddr) 1948 { 1949 struct xfrm_pol_inexact_node *n; 1950 u16 family; 1951 1952 if (!b) 1953 return false; 1954 1955 family = b->k.family; 1956 memset(cand, 0, sizeof(*cand)); 1957 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 1958 1959 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 1960 family); 1961 if (n) { 1962 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 1963 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 1964 family); 1965 if (n) 1966 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 1967 } 1968 1969 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 1970 family); 1971 if (n) 1972 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 1973 1974 return true; 1975 } 1976 1977 static struct xfrm_pol_inexact_bin * 1978 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 1979 u8 dir, u32 if_id) 1980 { 1981 struct xfrm_pol_inexact_key k = { 1982 .family = family, 1983 .type = type, 1984 .dir = dir, 1985 .if_id = if_id, 1986 }; 1987 1988 write_pnet(&k.net, net); 1989 1990 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 1991 xfrm_pol_inexact_params); 1992 } 1993 1994 static struct xfrm_pol_inexact_bin * 1995 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 1996 u8 dir, u32 if_id) 1997 { 1998 struct xfrm_pol_inexact_bin *bin; 1999 2000 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2001 2002 rcu_read_lock(); 2003 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2004 rcu_read_unlock(); 2005 2006 return bin; 2007 } 2008 2009 static struct xfrm_policy * 2010 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2011 struct xfrm_policy *prefer, 2012 const struct flowi *fl, 2013 u8 type, u16 family, int dir, u32 if_id) 2014 { 2015 u32 priority = prefer ? prefer->priority : ~0u; 2016 struct xfrm_policy *pol; 2017 2018 if (!chain) 2019 return NULL; 2020 2021 hlist_for_each_entry_rcu(pol, chain, bydst) { 2022 int err; 2023 2024 if (pol->priority > priority) 2025 break; 2026 2027 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2028 if (err) { 2029 if (err != -ESRCH) 2030 return ERR_PTR(err); 2031 2032 continue; 2033 } 2034 2035 if (prefer) { 2036 /* matches. Is it older than *prefer? */ 2037 if (pol->priority == priority && 2038 prefer->pos < pol->pos) 2039 return prefer; 2040 } 2041 2042 return pol; 2043 } 2044 2045 return NULL; 2046 } 2047 2048 static struct xfrm_policy * 2049 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2050 struct xfrm_policy *prefer, 2051 const struct flowi *fl, 2052 u8 type, u16 family, int dir, u32 if_id) 2053 { 2054 struct xfrm_policy *tmp; 2055 int i; 2056 2057 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2058 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2059 prefer, 2060 fl, type, family, dir, 2061 if_id); 2062 if (!tmp) 2063 continue; 2064 2065 if (IS_ERR(tmp)) 2066 return tmp; 2067 prefer = tmp; 2068 } 2069 2070 return prefer; 2071 } 2072 2073 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2074 const struct flowi *fl, 2075 u16 family, u8 dir, 2076 u32 if_id) 2077 { 2078 struct xfrm_pol_inexact_candidates cand; 2079 const xfrm_address_t *daddr, *saddr; 2080 struct xfrm_pol_inexact_bin *bin; 2081 struct xfrm_policy *pol, *ret; 2082 struct hlist_head *chain; 2083 unsigned int sequence; 2084 int err; 2085 2086 daddr = xfrm_flowi_daddr(fl, family); 2087 saddr = xfrm_flowi_saddr(fl, family); 2088 if (unlikely(!daddr || !saddr)) 2089 return NULL; 2090 2091 rcu_read_lock(); 2092 retry: 2093 do { 2094 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 2095 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2096 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 2097 2098 ret = NULL; 2099 hlist_for_each_entry_rcu(pol, chain, bydst) { 2100 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 2101 if (err) { 2102 if (err == -ESRCH) 2103 continue; 2104 else { 2105 ret = ERR_PTR(err); 2106 goto fail; 2107 } 2108 } else { 2109 ret = pol; 2110 break; 2111 } 2112 } 2113 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2114 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2115 daddr)) 2116 goto skip_inexact; 2117 2118 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2119 family, dir, if_id); 2120 if (pol) { 2121 ret = pol; 2122 if (IS_ERR(pol)) 2123 goto fail; 2124 } 2125 2126 skip_inexact: 2127 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 2128 goto retry; 2129 2130 if (ret && !xfrm_pol_hold_rcu(ret)) 2131 goto retry; 2132 fail: 2133 rcu_read_unlock(); 2134 2135 return ret; 2136 } 2137 2138 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2139 const struct flowi *fl, 2140 u16 family, u8 dir, u32 if_id) 2141 { 2142 #ifdef CONFIG_XFRM_SUB_POLICY 2143 struct xfrm_policy *pol; 2144 2145 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2146 dir, if_id); 2147 if (pol != NULL) 2148 return pol; 2149 #endif 2150 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2151 dir, if_id); 2152 } 2153 2154 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2155 const struct flowi *fl, 2156 u16 family, u32 if_id) 2157 { 2158 struct xfrm_policy *pol; 2159 2160 rcu_read_lock(); 2161 again: 2162 pol = rcu_dereference(sk->sk_policy[dir]); 2163 if (pol != NULL) { 2164 bool match; 2165 int err = 0; 2166 2167 if (pol->family != family) { 2168 pol = NULL; 2169 goto out; 2170 } 2171 2172 match = xfrm_selector_match(&pol->selector, fl, family); 2173 if (match) { 2174 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 2175 pol->if_id != if_id) { 2176 pol = NULL; 2177 goto out; 2178 } 2179 err = security_xfrm_policy_lookup(pol->security, 2180 fl->flowi_secid, 2181 dir); 2182 if (!err) { 2183 if (!xfrm_pol_hold_rcu(pol)) 2184 goto again; 2185 } else if (err == -ESRCH) { 2186 pol = NULL; 2187 } else { 2188 pol = ERR_PTR(err); 2189 } 2190 } else 2191 pol = NULL; 2192 } 2193 out: 2194 rcu_read_unlock(); 2195 return pol; 2196 } 2197 2198 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2199 { 2200 struct net *net = xp_net(pol); 2201 2202 list_add(&pol->walk.all, &net->xfrm.policy_all); 2203 net->xfrm.policy_count[dir]++; 2204 xfrm_pol_hold(pol); 2205 } 2206 2207 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2208 int dir) 2209 { 2210 struct net *net = xp_net(pol); 2211 2212 if (list_empty(&pol->walk.all)) 2213 return NULL; 2214 2215 /* Socket policies are not hashed. */ 2216 if (!hlist_unhashed(&pol->bydst)) { 2217 hlist_del_rcu(&pol->bydst); 2218 hlist_del_init(&pol->bydst_inexact_list); 2219 hlist_del(&pol->byidx); 2220 } 2221 2222 list_del_init(&pol->walk.all); 2223 net->xfrm.policy_count[dir]--; 2224 2225 return pol; 2226 } 2227 2228 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2229 { 2230 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2231 } 2232 2233 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2234 { 2235 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2236 } 2237 2238 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2239 { 2240 struct net *net = xp_net(pol); 2241 2242 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2243 pol = __xfrm_policy_unlink(pol, dir); 2244 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2245 if (pol) { 2246 xfrm_policy_kill(pol); 2247 return 0; 2248 } 2249 return -ENOENT; 2250 } 2251 EXPORT_SYMBOL(xfrm_policy_delete); 2252 2253 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2254 { 2255 struct net *net = sock_net(sk); 2256 struct xfrm_policy *old_pol; 2257 2258 #ifdef CONFIG_XFRM_SUB_POLICY 2259 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2260 return -EINVAL; 2261 #endif 2262 2263 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2264 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2265 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2266 if (pol) { 2267 pol->curlft.add_time = ktime_get_real_seconds(); 2268 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2269 xfrm_sk_policy_link(pol, dir); 2270 } 2271 rcu_assign_pointer(sk->sk_policy[dir], pol); 2272 if (old_pol) { 2273 if (pol) 2274 xfrm_policy_requeue(old_pol, pol); 2275 2276 /* Unlinking succeeds always. This is the only function 2277 * allowed to delete or replace socket policy. 2278 */ 2279 xfrm_sk_policy_unlink(old_pol, dir); 2280 } 2281 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2282 2283 if (old_pol) { 2284 xfrm_policy_kill(old_pol); 2285 } 2286 return 0; 2287 } 2288 2289 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2290 { 2291 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2292 struct net *net = xp_net(old); 2293 2294 if (newp) { 2295 newp->selector = old->selector; 2296 if (security_xfrm_policy_clone(old->security, 2297 &newp->security)) { 2298 kfree(newp); 2299 return NULL; /* ENOMEM */ 2300 } 2301 newp->lft = old->lft; 2302 newp->curlft = old->curlft; 2303 newp->mark = old->mark; 2304 newp->if_id = old->if_id; 2305 newp->action = old->action; 2306 newp->flags = old->flags; 2307 newp->xfrm_nr = old->xfrm_nr; 2308 newp->index = old->index; 2309 newp->type = old->type; 2310 newp->family = old->family; 2311 memcpy(newp->xfrm_vec, old->xfrm_vec, 2312 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2313 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2314 xfrm_sk_policy_link(newp, dir); 2315 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2316 xfrm_pol_put(newp); 2317 } 2318 return newp; 2319 } 2320 2321 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2322 { 2323 const struct xfrm_policy *p; 2324 struct xfrm_policy *np; 2325 int i, ret = 0; 2326 2327 rcu_read_lock(); 2328 for (i = 0; i < 2; i++) { 2329 p = rcu_dereference(osk->sk_policy[i]); 2330 if (p) { 2331 np = clone_policy(p, i); 2332 if (unlikely(!np)) { 2333 ret = -ENOMEM; 2334 break; 2335 } 2336 rcu_assign_pointer(sk->sk_policy[i], np); 2337 } 2338 } 2339 rcu_read_unlock(); 2340 return ret; 2341 } 2342 2343 static int 2344 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 2345 xfrm_address_t *remote, unsigned short family, u32 mark) 2346 { 2347 int err; 2348 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2349 2350 if (unlikely(afinfo == NULL)) 2351 return -EINVAL; 2352 err = afinfo->get_saddr(net, oif, local, remote, mark); 2353 rcu_read_unlock(); 2354 return err; 2355 } 2356 2357 /* Resolve list of templates for the flow, given policy. */ 2358 2359 static int 2360 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2361 struct xfrm_state **xfrm, unsigned short family) 2362 { 2363 struct net *net = xp_net(policy); 2364 int nx; 2365 int i, error; 2366 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2367 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2368 xfrm_address_t tmp; 2369 2370 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2371 struct xfrm_state *x; 2372 xfrm_address_t *remote = daddr; 2373 xfrm_address_t *local = saddr; 2374 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2375 2376 if (tmpl->mode == XFRM_MODE_TUNNEL || 2377 tmpl->mode == XFRM_MODE_BEET) { 2378 remote = &tmpl->id.daddr; 2379 local = &tmpl->saddr; 2380 if (xfrm_addr_any(local, tmpl->encap_family)) { 2381 error = xfrm_get_saddr(net, fl->flowi_oif, 2382 &tmp, remote, 2383 tmpl->encap_family, 0); 2384 if (error) 2385 goto fail; 2386 local = &tmp; 2387 } 2388 } 2389 2390 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2391 family, policy->if_id); 2392 2393 if (x && x->km.state == XFRM_STATE_VALID) { 2394 xfrm[nx++] = x; 2395 daddr = remote; 2396 saddr = local; 2397 continue; 2398 } 2399 if (x) { 2400 error = (x->km.state == XFRM_STATE_ERROR ? 2401 -EINVAL : -EAGAIN); 2402 xfrm_state_put(x); 2403 } else if (error == -ESRCH) { 2404 error = -EAGAIN; 2405 } 2406 2407 if (!tmpl->optional) 2408 goto fail; 2409 } 2410 return nx; 2411 2412 fail: 2413 for (nx--; nx >= 0; nx--) 2414 xfrm_state_put(xfrm[nx]); 2415 return error; 2416 } 2417 2418 static int 2419 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2420 struct xfrm_state **xfrm, unsigned short family) 2421 { 2422 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2423 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2424 int cnx = 0; 2425 int error; 2426 int ret; 2427 int i; 2428 2429 for (i = 0; i < npols; i++) { 2430 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2431 error = -ENOBUFS; 2432 goto fail; 2433 } 2434 2435 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2436 if (ret < 0) { 2437 error = ret; 2438 goto fail; 2439 } else 2440 cnx += ret; 2441 } 2442 2443 /* found states are sorted for outbound processing */ 2444 if (npols > 1) 2445 xfrm_state_sort(xfrm, tpp, cnx, family); 2446 2447 return cnx; 2448 2449 fail: 2450 for (cnx--; cnx >= 0; cnx--) 2451 xfrm_state_put(tpp[cnx]); 2452 return error; 2453 2454 } 2455 2456 static int xfrm_get_tos(const struct flowi *fl, int family) 2457 { 2458 if (family == AF_INET) 2459 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; 2460 2461 return 0; 2462 } 2463 2464 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2465 { 2466 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2467 struct dst_ops *dst_ops; 2468 struct xfrm_dst *xdst; 2469 2470 if (!afinfo) 2471 return ERR_PTR(-EINVAL); 2472 2473 switch (family) { 2474 case AF_INET: 2475 dst_ops = &net->xfrm.xfrm4_dst_ops; 2476 break; 2477 #if IS_ENABLED(CONFIG_IPV6) 2478 case AF_INET6: 2479 dst_ops = &net->xfrm.xfrm6_dst_ops; 2480 break; 2481 #endif 2482 default: 2483 BUG(); 2484 } 2485 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 2486 2487 if (likely(xdst)) { 2488 struct dst_entry *dst = &xdst->u.dst; 2489 2490 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 2491 } else 2492 xdst = ERR_PTR(-ENOBUFS); 2493 2494 rcu_read_unlock(); 2495 2496 return xdst; 2497 } 2498 2499 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2500 int nfheader_len) 2501 { 2502 if (dst->ops->family == AF_INET6) { 2503 struct rt6_info *rt = (struct rt6_info *)dst; 2504 path->path_cookie = rt6_get_cookie(rt); 2505 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2506 } 2507 } 2508 2509 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2510 const struct flowi *fl) 2511 { 2512 const struct xfrm_policy_afinfo *afinfo = 2513 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2514 int err; 2515 2516 if (!afinfo) 2517 return -EINVAL; 2518 2519 err = afinfo->fill_dst(xdst, dev, fl); 2520 2521 rcu_read_unlock(); 2522 2523 return err; 2524 } 2525 2526 2527 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2528 * all the metrics... Shortly, bundle a bundle. 2529 */ 2530 2531 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2532 struct xfrm_state **xfrm, 2533 struct xfrm_dst **bundle, 2534 int nx, 2535 const struct flowi *fl, 2536 struct dst_entry *dst) 2537 { 2538 const struct xfrm_state_afinfo *afinfo; 2539 const struct xfrm_mode *inner_mode; 2540 struct net *net = xp_net(policy); 2541 unsigned long now = jiffies; 2542 struct net_device *dev; 2543 struct xfrm_dst *xdst_prev = NULL; 2544 struct xfrm_dst *xdst0 = NULL; 2545 int i = 0; 2546 int err; 2547 int header_len = 0; 2548 int nfheader_len = 0; 2549 int trailer_len = 0; 2550 int tos; 2551 int family = policy->selector.family; 2552 xfrm_address_t saddr, daddr; 2553 2554 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2555 2556 tos = xfrm_get_tos(fl, family); 2557 2558 dst_hold(dst); 2559 2560 for (; i < nx; i++) { 2561 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2562 struct dst_entry *dst1 = &xdst->u.dst; 2563 2564 err = PTR_ERR(xdst); 2565 if (IS_ERR(xdst)) { 2566 dst_release(dst); 2567 goto put_states; 2568 } 2569 2570 bundle[i] = xdst; 2571 if (!xdst_prev) 2572 xdst0 = xdst; 2573 else 2574 /* Ref count is taken during xfrm_alloc_dst() 2575 * No need to do dst_clone() on dst1 2576 */ 2577 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2578 2579 if (xfrm[i]->sel.family == AF_UNSPEC) { 2580 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2581 xfrm_af2proto(family)); 2582 if (!inner_mode) { 2583 err = -EAFNOSUPPORT; 2584 dst_release(dst); 2585 goto put_states; 2586 } 2587 } else 2588 inner_mode = &xfrm[i]->inner_mode; 2589 2590 xdst->route = dst; 2591 dst_copy_metrics(dst1, dst); 2592 2593 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2594 __u32 mark = 0; 2595 2596 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2597 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2598 2599 family = xfrm[i]->props.family; 2600 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 2601 &saddr, &daddr, family, mark); 2602 err = PTR_ERR(dst); 2603 if (IS_ERR(dst)) 2604 goto put_states; 2605 } else 2606 dst_hold(dst); 2607 2608 dst1->xfrm = xfrm[i]; 2609 xdst->xfrm_genid = xfrm[i]->genid; 2610 2611 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2612 dst1->flags |= DST_HOST; 2613 dst1->lastuse = now; 2614 2615 dst1->input = dst_discard; 2616 2617 rcu_read_lock(); 2618 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2619 if (likely(afinfo)) 2620 dst1->output = afinfo->output; 2621 else 2622 dst1->output = dst_discard_out; 2623 rcu_read_unlock(); 2624 2625 xdst_prev = xdst; 2626 2627 header_len += xfrm[i]->props.header_len; 2628 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2629 nfheader_len += xfrm[i]->props.header_len; 2630 trailer_len += xfrm[i]->props.trailer_len; 2631 } 2632 2633 xfrm_dst_set_child(xdst_prev, dst); 2634 xdst0->path = dst; 2635 2636 err = -ENODEV; 2637 dev = dst->dev; 2638 if (!dev) 2639 goto free_dst; 2640 2641 xfrm_init_path(xdst0, dst, nfheader_len); 2642 xfrm_init_pmtu(bundle, nx); 2643 2644 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2645 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2646 err = xfrm_fill_dst(xdst_prev, dev, fl); 2647 if (err) 2648 goto free_dst; 2649 2650 xdst_prev->u.dst.header_len = header_len; 2651 xdst_prev->u.dst.trailer_len = trailer_len; 2652 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2653 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2654 } 2655 2656 return &xdst0->u.dst; 2657 2658 put_states: 2659 for (; i < nx; i++) 2660 xfrm_state_put(xfrm[i]); 2661 free_dst: 2662 if (xdst0) 2663 dst_release_immediate(&xdst0->u.dst); 2664 2665 return ERR_PTR(err); 2666 } 2667 2668 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2669 struct xfrm_policy **pols, 2670 int *num_pols, int *num_xfrms) 2671 { 2672 int i; 2673 2674 if (*num_pols == 0 || !pols[0]) { 2675 *num_pols = 0; 2676 *num_xfrms = 0; 2677 return 0; 2678 } 2679 if (IS_ERR(pols[0])) 2680 return PTR_ERR(pols[0]); 2681 2682 *num_xfrms = pols[0]->xfrm_nr; 2683 2684 #ifdef CONFIG_XFRM_SUB_POLICY 2685 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 2686 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2687 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2688 XFRM_POLICY_TYPE_MAIN, 2689 fl, family, 2690 XFRM_POLICY_OUT, 2691 pols[0]->if_id); 2692 if (pols[1]) { 2693 if (IS_ERR(pols[1])) { 2694 xfrm_pols_put(pols, *num_pols); 2695 return PTR_ERR(pols[1]); 2696 } 2697 (*num_pols)++; 2698 (*num_xfrms) += pols[1]->xfrm_nr; 2699 } 2700 } 2701 #endif 2702 for (i = 0; i < *num_pols; i++) { 2703 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2704 *num_xfrms = -1; 2705 break; 2706 } 2707 } 2708 2709 return 0; 2710 2711 } 2712 2713 static struct xfrm_dst * 2714 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2715 const struct flowi *fl, u16 family, 2716 struct dst_entry *dst_orig) 2717 { 2718 struct net *net = xp_net(pols[0]); 2719 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2720 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2721 struct xfrm_dst *xdst; 2722 struct dst_entry *dst; 2723 int err; 2724 2725 /* Try to instantiate a bundle */ 2726 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2727 if (err <= 0) { 2728 if (err == 0) 2729 return NULL; 2730 2731 if (err != -EAGAIN) 2732 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2733 return ERR_PTR(err); 2734 } 2735 2736 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2737 if (IS_ERR(dst)) { 2738 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2739 return ERR_CAST(dst); 2740 } 2741 2742 xdst = (struct xfrm_dst *)dst; 2743 xdst->num_xfrms = err; 2744 xdst->num_pols = num_pols; 2745 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2746 xdst->policy_genid = atomic_read(&pols[0]->genid); 2747 2748 return xdst; 2749 } 2750 2751 static void xfrm_policy_queue_process(struct timer_list *t) 2752 { 2753 struct sk_buff *skb; 2754 struct sock *sk; 2755 struct dst_entry *dst; 2756 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2757 struct net *net = xp_net(pol); 2758 struct xfrm_policy_queue *pq = &pol->polq; 2759 struct flowi fl; 2760 struct sk_buff_head list; 2761 2762 spin_lock(&pq->hold_queue.lock); 2763 skb = skb_peek(&pq->hold_queue); 2764 if (!skb) { 2765 spin_unlock(&pq->hold_queue.lock); 2766 goto out; 2767 } 2768 dst = skb_dst(skb); 2769 sk = skb->sk; 2770 xfrm_decode_session(skb, &fl, dst->ops->family); 2771 spin_unlock(&pq->hold_queue.lock); 2772 2773 dst_hold(xfrm_dst_path(dst)); 2774 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2775 if (IS_ERR(dst)) 2776 goto purge_queue; 2777 2778 if (dst->flags & DST_XFRM_QUEUE) { 2779 dst_release(dst); 2780 2781 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2782 goto purge_queue; 2783 2784 pq->timeout = pq->timeout << 1; 2785 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2786 xfrm_pol_hold(pol); 2787 goto out; 2788 } 2789 2790 dst_release(dst); 2791 2792 __skb_queue_head_init(&list); 2793 2794 spin_lock(&pq->hold_queue.lock); 2795 pq->timeout = 0; 2796 skb_queue_splice_init(&pq->hold_queue, &list); 2797 spin_unlock(&pq->hold_queue.lock); 2798 2799 while (!skb_queue_empty(&list)) { 2800 skb = __skb_dequeue(&list); 2801 2802 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 2803 dst_hold(xfrm_dst_path(skb_dst(skb))); 2804 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2805 if (IS_ERR(dst)) { 2806 kfree_skb(skb); 2807 continue; 2808 } 2809 2810 nf_reset(skb); 2811 skb_dst_drop(skb); 2812 skb_dst_set(skb, dst); 2813 2814 dst_output(net, skb->sk, skb); 2815 } 2816 2817 out: 2818 xfrm_pol_put(pol); 2819 return; 2820 2821 purge_queue: 2822 pq->timeout = 0; 2823 skb_queue_purge(&pq->hold_queue); 2824 xfrm_pol_put(pol); 2825 } 2826 2827 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2828 { 2829 unsigned long sched_next; 2830 struct dst_entry *dst = skb_dst(skb); 2831 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2832 struct xfrm_policy *pol = xdst->pols[0]; 2833 struct xfrm_policy_queue *pq = &pol->polq; 2834 2835 if (unlikely(skb_fclone_busy(sk, skb))) { 2836 kfree_skb(skb); 2837 return 0; 2838 } 2839 2840 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2841 kfree_skb(skb); 2842 return -EAGAIN; 2843 } 2844 2845 skb_dst_force(skb); 2846 2847 spin_lock_bh(&pq->hold_queue.lock); 2848 2849 if (!pq->timeout) 2850 pq->timeout = XFRM_QUEUE_TMO_MIN; 2851 2852 sched_next = jiffies + pq->timeout; 2853 2854 if (del_timer(&pq->hold_timer)) { 2855 if (time_before(pq->hold_timer.expires, sched_next)) 2856 sched_next = pq->hold_timer.expires; 2857 xfrm_pol_put(pol); 2858 } 2859 2860 __skb_queue_tail(&pq->hold_queue, skb); 2861 if (!mod_timer(&pq->hold_timer, sched_next)) 2862 xfrm_pol_hold(pol); 2863 2864 spin_unlock_bh(&pq->hold_queue.lock); 2865 2866 return 0; 2867 } 2868 2869 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 2870 struct xfrm_flo *xflo, 2871 const struct flowi *fl, 2872 int num_xfrms, 2873 u16 family) 2874 { 2875 int err; 2876 struct net_device *dev; 2877 struct dst_entry *dst; 2878 struct dst_entry *dst1; 2879 struct xfrm_dst *xdst; 2880 2881 xdst = xfrm_alloc_dst(net, family); 2882 if (IS_ERR(xdst)) 2883 return xdst; 2884 2885 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2886 net->xfrm.sysctl_larval_drop || 2887 num_xfrms <= 0) 2888 return xdst; 2889 2890 dst = xflo->dst_orig; 2891 dst1 = &xdst->u.dst; 2892 dst_hold(dst); 2893 xdst->route = dst; 2894 2895 dst_copy_metrics(dst1, dst); 2896 2897 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2898 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2899 dst1->lastuse = jiffies; 2900 2901 dst1->input = dst_discard; 2902 dst1->output = xdst_queue_output; 2903 2904 dst_hold(dst); 2905 xfrm_dst_set_child(xdst, dst); 2906 xdst->path = dst; 2907 2908 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2909 2910 err = -ENODEV; 2911 dev = dst->dev; 2912 if (!dev) 2913 goto free_dst; 2914 2915 err = xfrm_fill_dst(xdst, dev, fl); 2916 if (err) 2917 goto free_dst; 2918 2919 out: 2920 return xdst; 2921 2922 free_dst: 2923 dst_release(dst1); 2924 xdst = ERR_PTR(err); 2925 goto out; 2926 } 2927 2928 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 2929 const struct flowi *fl, 2930 u16 family, u8 dir, 2931 struct xfrm_flo *xflo, u32 if_id) 2932 { 2933 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2934 int num_pols = 0, num_xfrms = 0, err; 2935 struct xfrm_dst *xdst; 2936 2937 /* Resolve policies to use if we couldn't get them from 2938 * previous cache entry */ 2939 num_pols = 1; 2940 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 2941 err = xfrm_expand_policies(fl, family, pols, 2942 &num_pols, &num_xfrms); 2943 if (err < 0) 2944 goto inc_error; 2945 if (num_pols == 0) 2946 return NULL; 2947 if (num_xfrms <= 0) 2948 goto make_dummy_bundle; 2949 2950 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2951 xflo->dst_orig); 2952 if (IS_ERR(xdst)) { 2953 err = PTR_ERR(xdst); 2954 if (err == -EREMOTE) { 2955 xfrm_pols_put(pols, num_pols); 2956 return NULL; 2957 } 2958 2959 if (err != -EAGAIN) 2960 goto error; 2961 goto make_dummy_bundle; 2962 } else if (xdst == NULL) { 2963 num_xfrms = 0; 2964 goto make_dummy_bundle; 2965 } 2966 2967 return xdst; 2968 2969 make_dummy_bundle: 2970 /* We found policies, but there's no bundles to instantiate: 2971 * either because the policy blocks, has no transformations or 2972 * we could not build template (no xfrm_states).*/ 2973 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2974 if (IS_ERR(xdst)) { 2975 xfrm_pols_put(pols, num_pols); 2976 return ERR_CAST(xdst); 2977 } 2978 xdst->num_pols = num_pols; 2979 xdst->num_xfrms = num_xfrms; 2980 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2981 2982 return xdst; 2983 2984 inc_error: 2985 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2986 error: 2987 xfrm_pols_put(pols, num_pols); 2988 return ERR_PTR(err); 2989 } 2990 2991 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2992 struct dst_entry *dst_orig) 2993 { 2994 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2995 struct dst_entry *ret; 2996 2997 if (!afinfo) { 2998 dst_release(dst_orig); 2999 return ERR_PTR(-EINVAL); 3000 } else { 3001 ret = afinfo->blackhole_route(net, dst_orig); 3002 } 3003 rcu_read_unlock(); 3004 3005 return ret; 3006 } 3007 3008 /* Finds/creates a bundle for given flow and if_id 3009 * 3010 * At the moment we eat a raw IP route. Mostly to speed up lookups 3011 * on interfaces with disabled IPsec. 3012 * 3013 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3014 * compatibility 3015 */ 3016 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3017 struct dst_entry *dst_orig, 3018 const struct flowi *fl, 3019 const struct sock *sk, 3020 int flags, u32 if_id) 3021 { 3022 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3023 struct xfrm_dst *xdst; 3024 struct dst_entry *dst, *route; 3025 u16 family = dst_orig->ops->family; 3026 u8 dir = XFRM_POLICY_OUT; 3027 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3028 3029 dst = NULL; 3030 xdst = NULL; 3031 route = NULL; 3032 3033 sk = sk_const_to_full_sk(sk); 3034 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3035 num_pols = 1; 3036 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3037 if_id); 3038 err = xfrm_expand_policies(fl, family, pols, 3039 &num_pols, &num_xfrms); 3040 if (err < 0) 3041 goto dropdst; 3042 3043 if (num_pols) { 3044 if (num_xfrms <= 0) { 3045 drop_pols = num_pols; 3046 goto no_transform; 3047 } 3048 3049 xdst = xfrm_resolve_and_create_bundle( 3050 pols, num_pols, fl, 3051 family, dst_orig); 3052 3053 if (IS_ERR(xdst)) { 3054 xfrm_pols_put(pols, num_pols); 3055 err = PTR_ERR(xdst); 3056 if (err == -EREMOTE) 3057 goto nopol; 3058 3059 goto dropdst; 3060 } else if (xdst == NULL) { 3061 num_xfrms = 0; 3062 drop_pols = num_pols; 3063 goto no_transform; 3064 } 3065 3066 route = xdst->route; 3067 } 3068 } 3069 3070 if (xdst == NULL) { 3071 struct xfrm_flo xflo; 3072 3073 xflo.dst_orig = dst_orig; 3074 xflo.flags = flags; 3075 3076 /* To accelerate a bit... */ 3077 if ((dst_orig->flags & DST_NOXFRM) || 3078 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 3079 goto nopol; 3080 3081 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3082 if (xdst == NULL) 3083 goto nopol; 3084 if (IS_ERR(xdst)) { 3085 err = PTR_ERR(xdst); 3086 goto dropdst; 3087 } 3088 3089 num_pols = xdst->num_pols; 3090 num_xfrms = xdst->num_xfrms; 3091 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3092 route = xdst->route; 3093 } 3094 3095 dst = &xdst->u.dst; 3096 if (route == NULL && num_xfrms > 0) { 3097 /* The only case when xfrm_bundle_lookup() returns a 3098 * bundle with null route, is when the template could 3099 * not be resolved. It means policies are there, but 3100 * bundle could not be created, since we don't yet 3101 * have the xfrm_state's. We need to wait for KM to 3102 * negotiate new SA's or bail out with error.*/ 3103 if (net->xfrm.sysctl_larval_drop) { 3104 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3105 err = -EREMOTE; 3106 goto error; 3107 } 3108 3109 err = -EAGAIN; 3110 3111 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3112 goto error; 3113 } 3114 3115 no_transform: 3116 if (num_pols == 0) 3117 goto nopol; 3118 3119 if ((flags & XFRM_LOOKUP_ICMP) && 3120 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3121 err = -ENOENT; 3122 goto error; 3123 } 3124 3125 for (i = 0; i < num_pols; i++) 3126 pols[i]->curlft.use_time = ktime_get_real_seconds(); 3127 3128 if (num_xfrms < 0) { 3129 /* Prohibit the flow */ 3130 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3131 err = -EPERM; 3132 goto error; 3133 } else if (num_xfrms > 0) { 3134 /* Flow transformed */ 3135 dst_release(dst_orig); 3136 } else { 3137 /* Flow passes untransformed */ 3138 dst_release(dst); 3139 dst = dst_orig; 3140 } 3141 ok: 3142 xfrm_pols_put(pols, drop_pols); 3143 if (dst && dst->xfrm && 3144 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3145 dst->flags |= DST_XFRM_TUNNEL; 3146 return dst; 3147 3148 nopol: 3149 if (!(flags & XFRM_LOOKUP_ICMP)) { 3150 dst = dst_orig; 3151 goto ok; 3152 } 3153 err = -ENOENT; 3154 error: 3155 dst_release(dst); 3156 dropdst: 3157 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3158 dst_release(dst_orig); 3159 xfrm_pols_put(pols, drop_pols); 3160 return ERR_PTR(err); 3161 } 3162 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3163 3164 /* Main function: finds/creates a bundle for given flow. 3165 * 3166 * At the moment we eat a raw IP route. Mostly to speed up lookups 3167 * on interfaces with disabled IPsec. 3168 */ 3169 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3170 const struct flowi *fl, const struct sock *sk, 3171 int flags) 3172 { 3173 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3174 } 3175 EXPORT_SYMBOL(xfrm_lookup); 3176 3177 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3178 * Otherwise we may send out blackholed packets. 3179 */ 3180 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3181 const struct flowi *fl, 3182 const struct sock *sk, int flags) 3183 { 3184 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3185 flags | XFRM_LOOKUP_QUEUE | 3186 XFRM_LOOKUP_KEEP_DST_REF); 3187 3188 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 3189 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3190 3191 if (IS_ERR(dst)) 3192 dst_release(dst_orig); 3193 3194 return dst; 3195 } 3196 EXPORT_SYMBOL(xfrm_lookup_route); 3197 3198 static inline int 3199 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3200 { 3201 struct sec_path *sp = skb_sec_path(skb); 3202 struct xfrm_state *x; 3203 3204 if (!sp || idx < 0 || idx >= sp->len) 3205 return 0; 3206 x = sp->xvec[idx]; 3207 if (!x->type->reject) 3208 return 0; 3209 return x->type->reject(x, skb, fl); 3210 } 3211 3212 /* When skb is transformed back to its "native" form, we have to 3213 * check policy restrictions. At the moment we make this in maximally 3214 * stupid way. Shame on me. :-) Of course, connected sockets must 3215 * have policy cached at them. 3216 */ 3217 3218 static inline int 3219 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3220 unsigned short family) 3221 { 3222 if (xfrm_state_kern(x)) 3223 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3224 return x->id.proto == tmpl->id.proto && 3225 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3226 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3227 x->props.mode == tmpl->mode && 3228 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3229 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3230 !(x->props.mode != XFRM_MODE_TRANSPORT && 3231 xfrm_state_addr_cmp(tmpl, x, family)); 3232 } 3233 3234 /* 3235 * 0 or more than 0 is returned when validation is succeeded (either bypass 3236 * because of optional transport mode, or next index of the mathced secpath 3237 * state with the template. 3238 * -1 is returned when no matching template is found. 3239 * Otherwise "-2 - errored_index" is returned. 3240 */ 3241 static inline int 3242 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3243 unsigned short family) 3244 { 3245 int idx = start; 3246 3247 if (tmpl->optional) { 3248 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3249 return start; 3250 } else 3251 start = -1; 3252 for (; idx < sp->len; idx++) { 3253 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 3254 return ++idx; 3255 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3256 if (start == -1) 3257 start = -2-idx; 3258 break; 3259 } 3260 } 3261 return start; 3262 } 3263 3264 static void 3265 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse) 3266 { 3267 const struct iphdr *iph = ip_hdr(skb); 3268 u8 *xprth = skb_network_header(skb) + iph->ihl * 4; 3269 struct flowi4 *fl4 = &fl->u.ip4; 3270 int oif = 0; 3271 3272 if (skb_dst(skb)) 3273 oif = skb_dst(skb)->dev->ifindex; 3274 3275 memset(fl4, 0, sizeof(struct flowi4)); 3276 fl4->flowi4_mark = skb->mark; 3277 fl4->flowi4_oif = reverse ? skb->skb_iif : oif; 3278 3279 if (!ip_is_fragment(iph)) { 3280 switch (iph->protocol) { 3281 case IPPROTO_UDP: 3282 case IPPROTO_UDPLITE: 3283 case IPPROTO_TCP: 3284 case IPPROTO_SCTP: 3285 case IPPROTO_DCCP: 3286 if (xprth + 4 < skb->data || 3287 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3288 __be16 *ports; 3289 3290 xprth = skb_network_header(skb) + iph->ihl * 4; 3291 ports = (__be16 *)xprth; 3292 3293 fl4->fl4_sport = ports[!!reverse]; 3294 fl4->fl4_dport = ports[!reverse]; 3295 } 3296 break; 3297 case IPPROTO_ICMP: 3298 if (xprth + 2 < skb->data || 3299 pskb_may_pull(skb, xprth + 2 - skb->data)) { 3300 u8 *icmp; 3301 3302 xprth = skb_network_header(skb) + iph->ihl * 4; 3303 icmp = xprth; 3304 3305 fl4->fl4_icmp_type = icmp[0]; 3306 fl4->fl4_icmp_code = icmp[1]; 3307 } 3308 break; 3309 case IPPROTO_ESP: 3310 if (xprth + 4 < skb->data || 3311 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3312 __be32 *ehdr; 3313 3314 xprth = skb_network_header(skb) + iph->ihl * 4; 3315 ehdr = (__be32 *)xprth; 3316 3317 fl4->fl4_ipsec_spi = ehdr[0]; 3318 } 3319 break; 3320 case IPPROTO_AH: 3321 if (xprth + 8 < skb->data || 3322 pskb_may_pull(skb, xprth + 8 - skb->data)) { 3323 __be32 *ah_hdr; 3324 3325 xprth = skb_network_header(skb) + iph->ihl * 4; 3326 ah_hdr = (__be32 *)xprth; 3327 3328 fl4->fl4_ipsec_spi = ah_hdr[1]; 3329 } 3330 break; 3331 case IPPROTO_COMP: 3332 if (xprth + 4 < skb->data || 3333 pskb_may_pull(skb, xprth + 4 - skb->data)) { 3334 __be16 *ipcomp_hdr; 3335 3336 xprth = skb_network_header(skb) + iph->ihl * 4; 3337 ipcomp_hdr = (__be16 *)xprth; 3338 3339 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1])); 3340 } 3341 break; 3342 case IPPROTO_GRE: 3343 if (xprth + 12 < skb->data || 3344 pskb_may_pull(skb, xprth + 12 - skb->data)) { 3345 __be16 *greflags; 3346 __be32 *gre_hdr; 3347 3348 xprth = skb_network_header(skb) + iph->ihl * 4; 3349 greflags = (__be16 *)xprth; 3350 gre_hdr = (__be32 *)xprth; 3351 3352 if (greflags[0] & GRE_KEY) { 3353 if (greflags[0] & GRE_CSUM) 3354 gre_hdr++; 3355 fl4->fl4_gre_key = gre_hdr[1]; 3356 } 3357 } 3358 break; 3359 default: 3360 fl4->fl4_ipsec_spi = 0; 3361 break; 3362 } 3363 } 3364 fl4->flowi4_proto = iph->protocol; 3365 fl4->daddr = reverse ? iph->saddr : iph->daddr; 3366 fl4->saddr = reverse ? iph->daddr : iph->saddr; 3367 fl4->flowi4_tos = iph->tos; 3368 } 3369 3370 #if IS_ENABLED(CONFIG_IPV6) 3371 static void 3372 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) 3373 { 3374 struct flowi6 *fl6 = &fl->u.ip6; 3375 int onlyproto = 0; 3376 const struct ipv6hdr *hdr = ipv6_hdr(skb); 3377 u32 offset = sizeof(*hdr); 3378 struct ipv6_opt_hdr *exthdr; 3379 const unsigned char *nh = skb_network_header(skb); 3380 u16 nhoff = IP6CB(skb)->nhoff; 3381 int oif = 0; 3382 u8 nexthdr; 3383 3384 if (!nhoff) 3385 nhoff = offsetof(struct ipv6hdr, nexthdr); 3386 3387 nexthdr = nh[nhoff]; 3388 3389 if (skb_dst(skb)) 3390 oif = skb_dst(skb)->dev->ifindex; 3391 3392 memset(fl6, 0, sizeof(struct flowi6)); 3393 fl6->flowi6_mark = skb->mark; 3394 fl6->flowi6_oif = reverse ? skb->skb_iif : oif; 3395 3396 fl6->daddr = reverse ? hdr->saddr : hdr->daddr; 3397 fl6->saddr = reverse ? hdr->daddr : hdr->saddr; 3398 3399 while (nh + offset + sizeof(*exthdr) < skb->data || 3400 pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { 3401 nh = skb_network_header(skb); 3402 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3403 3404 switch (nexthdr) { 3405 case NEXTHDR_FRAGMENT: 3406 onlyproto = 1; 3407 /* fall through */ 3408 case NEXTHDR_ROUTING: 3409 case NEXTHDR_HOP: 3410 case NEXTHDR_DEST: 3411 offset += ipv6_optlen(exthdr); 3412 nexthdr = exthdr->nexthdr; 3413 exthdr = (struct ipv6_opt_hdr *)(nh + offset); 3414 break; 3415 case IPPROTO_UDP: 3416 case IPPROTO_UDPLITE: 3417 case IPPROTO_TCP: 3418 case IPPROTO_SCTP: 3419 case IPPROTO_DCCP: 3420 if (!onlyproto && (nh + offset + 4 < skb->data || 3421 pskb_may_pull(skb, nh + offset + 4 - skb->data))) { 3422 __be16 *ports; 3423 3424 nh = skb_network_header(skb); 3425 ports = (__be16 *)(nh + offset); 3426 fl6->fl6_sport = ports[!!reverse]; 3427 fl6->fl6_dport = ports[!reverse]; 3428 } 3429 fl6->flowi6_proto = nexthdr; 3430 return; 3431 case IPPROTO_ICMPV6: 3432 if (!onlyproto && (nh + offset + 2 < skb->data || 3433 pskb_may_pull(skb, nh + offset + 2 - skb->data))) { 3434 u8 *icmp; 3435 3436 nh = skb_network_header(skb); 3437 icmp = (u8 *)(nh + offset); 3438 fl6->fl6_icmp_type = icmp[0]; 3439 fl6->fl6_icmp_code = icmp[1]; 3440 } 3441 fl6->flowi6_proto = nexthdr; 3442 return; 3443 #if IS_ENABLED(CONFIG_IPV6_MIP6) 3444 case IPPROTO_MH: 3445 offset += ipv6_optlen(exthdr); 3446 if (!onlyproto && (nh + offset + 3 < skb->data || 3447 pskb_may_pull(skb, nh + offset + 3 - skb->data))) { 3448 struct ip6_mh *mh; 3449 3450 nh = skb_network_header(skb); 3451 mh = (struct ip6_mh *)(nh + offset); 3452 fl6->fl6_mh_type = mh->ip6mh_type; 3453 } 3454 fl6->flowi6_proto = nexthdr; 3455 return; 3456 #endif 3457 /* XXX Why are there these headers? */ 3458 case IPPROTO_AH: 3459 case IPPROTO_ESP: 3460 case IPPROTO_COMP: 3461 default: 3462 fl6->fl6_ipsec_spi = 0; 3463 fl6->flowi6_proto = nexthdr; 3464 return; 3465 } 3466 } 3467 } 3468 #endif 3469 3470 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 3471 unsigned int family, int reverse) 3472 { 3473 switch (family) { 3474 case AF_INET: 3475 decode_session4(skb, fl, reverse); 3476 break; 3477 #if IS_ENABLED(CONFIG_IPV6) 3478 case AF_INET6: 3479 decode_session6(skb, fl, reverse); 3480 break; 3481 #endif 3482 default: 3483 return -EAFNOSUPPORT; 3484 } 3485 3486 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3487 } 3488 EXPORT_SYMBOL(__xfrm_decode_session); 3489 3490 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3491 { 3492 for (; k < sp->len; k++) { 3493 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3494 *idxp = k; 3495 return 1; 3496 } 3497 } 3498 3499 return 0; 3500 } 3501 3502 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3503 unsigned short family) 3504 { 3505 struct net *net = dev_net(skb->dev); 3506 struct xfrm_policy *pol; 3507 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3508 int npols = 0; 3509 int xfrm_nr; 3510 int pi; 3511 int reverse; 3512 struct flowi fl; 3513 int xerr_idx = -1; 3514 const struct xfrm_if_cb *ifcb; 3515 struct sec_path *sp; 3516 struct xfrm_if *xi; 3517 u32 if_id = 0; 3518 3519 rcu_read_lock(); 3520 ifcb = xfrm_if_get_cb(); 3521 3522 if (ifcb) { 3523 xi = ifcb->decode_session(skb, family); 3524 if (xi) { 3525 if_id = xi->p.if_id; 3526 net = xi->net; 3527 } 3528 } 3529 rcu_read_unlock(); 3530 3531 reverse = dir & ~XFRM_POLICY_MASK; 3532 dir &= XFRM_POLICY_MASK; 3533 3534 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 3535 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3536 return 0; 3537 } 3538 3539 nf_nat_decode_session(skb, &fl, family); 3540 3541 /* First, check used SA against their selectors. */ 3542 sp = skb_sec_path(skb); 3543 if (sp) { 3544 int i; 3545 3546 for (i = sp->len - 1; i >= 0; i--) { 3547 struct xfrm_state *x = sp->xvec[i]; 3548 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3549 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3550 return 0; 3551 } 3552 } 3553 } 3554 3555 pol = NULL; 3556 sk = sk_to_full_sk(sk); 3557 if (sk && sk->sk_policy[dir]) { 3558 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3559 if (IS_ERR(pol)) { 3560 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3561 return 0; 3562 } 3563 } 3564 3565 if (!pol) 3566 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3567 3568 if (IS_ERR(pol)) { 3569 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3570 return 0; 3571 } 3572 3573 if (!pol) { 3574 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) { 3575 xfrm_secpath_reject(xerr_idx, skb, &fl); 3576 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3577 return 0; 3578 } 3579 return 1; 3580 } 3581 3582 pol->curlft.use_time = ktime_get_real_seconds(); 3583 3584 pols[0] = pol; 3585 npols++; 3586 #ifdef CONFIG_XFRM_SUB_POLICY 3587 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3588 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3589 &fl, family, 3590 XFRM_POLICY_IN, if_id); 3591 if (pols[1]) { 3592 if (IS_ERR(pols[1])) { 3593 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3594 return 0; 3595 } 3596 pols[1]->curlft.use_time = ktime_get_real_seconds(); 3597 npols++; 3598 } 3599 } 3600 #endif 3601 3602 if (pol->action == XFRM_POLICY_ALLOW) { 3603 static struct sec_path dummy; 3604 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3605 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3606 struct xfrm_tmpl **tpp = tp; 3607 int ti = 0; 3608 int i, k; 3609 3610 sp = skb_sec_path(skb); 3611 if (!sp) 3612 sp = &dummy; 3613 3614 for (pi = 0; pi < npols; pi++) { 3615 if (pols[pi] != pol && 3616 pols[pi]->action != XFRM_POLICY_ALLOW) { 3617 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3618 goto reject; 3619 } 3620 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3621 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3622 goto reject_error; 3623 } 3624 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3625 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3626 } 3627 xfrm_nr = ti; 3628 if (npols > 1) { 3629 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 3630 tpp = stp; 3631 } 3632 3633 /* For each tunnel xfrm, find the first matching tmpl. 3634 * For each tmpl before that, find corresponding xfrm. 3635 * Order is _important_. Later we will implement 3636 * some barriers, but at the moment barriers 3637 * are implied between each two transformations. 3638 */ 3639 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3640 k = xfrm_policy_ok(tpp[i], sp, k, family); 3641 if (k < 0) { 3642 if (k < -1) 3643 /* "-2 - errored_index" returned */ 3644 xerr_idx = -(2+k); 3645 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3646 goto reject; 3647 } 3648 } 3649 3650 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3651 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3652 goto reject; 3653 } 3654 3655 xfrm_pols_put(pols, npols); 3656 return 1; 3657 } 3658 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3659 3660 reject: 3661 xfrm_secpath_reject(xerr_idx, skb, &fl); 3662 reject_error: 3663 xfrm_pols_put(pols, npols); 3664 return 0; 3665 } 3666 EXPORT_SYMBOL(__xfrm_policy_check); 3667 3668 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3669 { 3670 struct net *net = dev_net(skb->dev); 3671 struct flowi fl; 3672 struct dst_entry *dst; 3673 int res = 1; 3674 3675 if (xfrm_decode_session(skb, &fl, family) < 0) { 3676 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3677 return 0; 3678 } 3679 3680 skb_dst_force(skb); 3681 if (!skb_dst(skb)) { 3682 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3683 return 0; 3684 } 3685 3686 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3687 if (IS_ERR(dst)) { 3688 res = 0; 3689 dst = NULL; 3690 } 3691 skb_dst_set(skb, dst); 3692 return res; 3693 } 3694 EXPORT_SYMBOL(__xfrm_route_forward); 3695 3696 /* Optimize later using cookies and generation ids. */ 3697 3698 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3699 { 3700 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3701 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3702 * get validated by dst_ops->check on every use. We do this 3703 * because when a normal route referenced by an XFRM dst is 3704 * obsoleted we do not go looking around for all parent 3705 * referencing XFRM dsts so that we can invalidate them. It 3706 * is just too much work. Instead we make the checks here on 3707 * every use. For example: 3708 * 3709 * XFRM dst A --> IPv4 dst X 3710 * 3711 * X is the "xdst->route" of A (X is also the "dst->path" of A 3712 * in this example). If X is marked obsolete, "A" will not 3713 * notice. That's what we are validating here via the 3714 * stale_bundle() check. 3715 * 3716 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3717 * be marked on it. 3718 * This will force stale_bundle() to fail on any xdst bundle with 3719 * this dst linked in it. 3720 */ 3721 if (dst->obsolete < 0 && !stale_bundle(dst)) 3722 return dst; 3723 3724 return NULL; 3725 } 3726 3727 static int stale_bundle(struct dst_entry *dst) 3728 { 3729 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3730 } 3731 3732 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3733 { 3734 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3735 dst->dev = dev_net(dev)->loopback_dev; 3736 dev_hold(dst->dev); 3737 dev_put(dev); 3738 } 3739 } 3740 EXPORT_SYMBOL(xfrm_dst_ifdown); 3741 3742 static void xfrm_link_failure(struct sk_buff *skb) 3743 { 3744 /* Impossible. Such dst must be popped before reaches point of failure. */ 3745 } 3746 3747 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 3748 { 3749 if (dst) { 3750 if (dst->obsolete) { 3751 dst_release(dst); 3752 dst = NULL; 3753 } 3754 } 3755 return dst; 3756 } 3757 3758 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3759 { 3760 while (nr--) { 3761 struct xfrm_dst *xdst = bundle[nr]; 3762 u32 pmtu, route_mtu_cached; 3763 struct dst_entry *dst; 3764 3765 dst = &xdst->u.dst; 3766 pmtu = dst_mtu(xfrm_dst_child(dst)); 3767 xdst->child_mtu_cached = pmtu; 3768 3769 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3770 3771 route_mtu_cached = dst_mtu(xdst->route); 3772 xdst->route_mtu_cached = route_mtu_cached; 3773 3774 if (pmtu > route_mtu_cached) 3775 pmtu = route_mtu_cached; 3776 3777 dst_metric_set(dst, RTAX_MTU, pmtu); 3778 } 3779 } 3780 3781 /* Check that the bundle accepts the flow and its components are 3782 * still valid. 3783 */ 3784 3785 static int xfrm_bundle_ok(struct xfrm_dst *first) 3786 { 3787 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3788 struct dst_entry *dst = &first->u.dst; 3789 struct xfrm_dst *xdst; 3790 int start_from, nr; 3791 u32 mtu; 3792 3793 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3794 (dst->dev && !netif_running(dst->dev))) 3795 return 0; 3796 3797 if (dst->flags & DST_XFRM_QUEUE) 3798 return 1; 3799 3800 start_from = nr = 0; 3801 do { 3802 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3803 3804 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3805 return 0; 3806 if (xdst->xfrm_genid != dst->xfrm->genid) 3807 return 0; 3808 if (xdst->num_pols > 0 && 3809 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3810 return 0; 3811 3812 bundle[nr++] = xdst; 3813 3814 mtu = dst_mtu(xfrm_dst_child(dst)); 3815 if (xdst->child_mtu_cached != mtu) { 3816 start_from = nr; 3817 xdst->child_mtu_cached = mtu; 3818 } 3819 3820 if (!dst_check(xdst->route, xdst->route_cookie)) 3821 return 0; 3822 mtu = dst_mtu(xdst->route); 3823 if (xdst->route_mtu_cached != mtu) { 3824 start_from = nr; 3825 xdst->route_mtu_cached = mtu; 3826 } 3827 3828 dst = xfrm_dst_child(dst); 3829 } while (dst->xfrm); 3830 3831 if (likely(!start_from)) 3832 return 1; 3833 3834 xdst = bundle[start_from - 1]; 3835 mtu = xdst->child_mtu_cached; 3836 while (start_from--) { 3837 dst = &xdst->u.dst; 3838 3839 mtu = xfrm_state_mtu(dst->xfrm, mtu); 3840 if (mtu > xdst->route_mtu_cached) 3841 mtu = xdst->route_mtu_cached; 3842 dst_metric_set(dst, RTAX_MTU, mtu); 3843 if (!start_from) 3844 break; 3845 3846 xdst = bundle[start_from - 1]; 3847 xdst->child_mtu_cached = mtu; 3848 } 3849 3850 return 1; 3851 } 3852 3853 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 3854 { 3855 return dst_metric_advmss(xfrm_dst_path(dst)); 3856 } 3857 3858 static unsigned int xfrm_mtu(const struct dst_entry *dst) 3859 { 3860 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 3861 3862 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 3863 } 3864 3865 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 3866 const void *daddr) 3867 { 3868 while (dst->xfrm) { 3869 const struct xfrm_state *xfrm = dst->xfrm; 3870 3871 dst = xfrm_dst_child(dst); 3872 3873 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 3874 continue; 3875 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 3876 daddr = xfrm->coaddr; 3877 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 3878 daddr = &xfrm->id.daddr; 3879 } 3880 return daddr; 3881 } 3882 3883 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 3884 struct sk_buff *skb, 3885 const void *daddr) 3886 { 3887 const struct dst_entry *path = xfrm_dst_path(dst); 3888 3889 if (!skb) 3890 daddr = xfrm_get_dst_nexthop(dst, daddr); 3891 return path->ops->neigh_lookup(path, skb, daddr); 3892 } 3893 3894 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 3895 { 3896 const struct dst_entry *path = xfrm_dst_path(dst); 3897 3898 daddr = xfrm_get_dst_nexthop(dst, daddr); 3899 path->ops->confirm_neigh(path, daddr); 3900 } 3901 3902 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 3903 { 3904 int err = 0; 3905 3906 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 3907 return -EAFNOSUPPORT; 3908 3909 spin_lock(&xfrm_policy_afinfo_lock); 3910 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 3911 err = -EEXIST; 3912 else { 3913 struct dst_ops *dst_ops = afinfo->dst_ops; 3914 if (likely(dst_ops->kmem_cachep == NULL)) 3915 dst_ops->kmem_cachep = xfrm_dst_cache; 3916 if (likely(dst_ops->check == NULL)) 3917 dst_ops->check = xfrm_dst_check; 3918 if (likely(dst_ops->default_advmss == NULL)) 3919 dst_ops->default_advmss = xfrm_default_advmss; 3920 if (likely(dst_ops->mtu == NULL)) 3921 dst_ops->mtu = xfrm_mtu; 3922 if (likely(dst_ops->negative_advice == NULL)) 3923 dst_ops->negative_advice = xfrm_negative_advice; 3924 if (likely(dst_ops->link_failure == NULL)) 3925 dst_ops->link_failure = xfrm_link_failure; 3926 if (likely(dst_ops->neigh_lookup == NULL)) 3927 dst_ops->neigh_lookup = xfrm_neigh_lookup; 3928 if (likely(!dst_ops->confirm_neigh)) 3929 dst_ops->confirm_neigh = xfrm_confirm_neigh; 3930 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 3931 } 3932 spin_unlock(&xfrm_policy_afinfo_lock); 3933 3934 return err; 3935 } 3936 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 3937 3938 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 3939 { 3940 struct dst_ops *dst_ops = afinfo->dst_ops; 3941 int i; 3942 3943 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 3944 if (xfrm_policy_afinfo[i] != afinfo) 3945 continue; 3946 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 3947 break; 3948 } 3949 3950 synchronize_rcu(); 3951 3952 dst_ops->kmem_cachep = NULL; 3953 dst_ops->check = NULL; 3954 dst_ops->negative_advice = NULL; 3955 dst_ops->link_failure = NULL; 3956 } 3957 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 3958 3959 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 3960 { 3961 spin_lock(&xfrm_if_cb_lock); 3962 rcu_assign_pointer(xfrm_if_cb, ifcb); 3963 spin_unlock(&xfrm_if_cb_lock); 3964 } 3965 EXPORT_SYMBOL(xfrm_if_register_cb); 3966 3967 void xfrm_if_unregister_cb(void) 3968 { 3969 RCU_INIT_POINTER(xfrm_if_cb, NULL); 3970 synchronize_rcu(); 3971 } 3972 EXPORT_SYMBOL(xfrm_if_unregister_cb); 3973 3974 #ifdef CONFIG_XFRM_STATISTICS 3975 static int __net_init xfrm_statistics_init(struct net *net) 3976 { 3977 int rv; 3978 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 3979 if (!net->mib.xfrm_statistics) 3980 return -ENOMEM; 3981 rv = xfrm_proc_init(net); 3982 if (rv < 0) 3983 free_percpu(net->mib.xfrm_statistics); 3984 return rv; 3985 } 3986 3987 static void xfrm_statistics_fini(struct net *net) 3988 { 3989 xfrm_proc_fini(net); 3990 free_percpu(net->mib.xfrm_statistics); 3991 } 3992 #else 3993 static int __net_init xfrm_statistics_init(struct net *net) 3994 { 3995 return 0; 3996 } 3997 3998 static void xfrm_statistics_fini(struct net *net) 3999 { 4000 } 4001 #endif 4002 4003 static int __net_init xfrm_policy_init(struct net *net) 4004 { 4005 unsigned int hmask, sz; 4006 int dir, err; 4007 4008 if (net_eq(net, &init_net)) { 4009 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 4010 sizeof(struct xfrm_dst), 4011 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 4012 NULL); 4013 err = rhashtable_init(&xfrm_policy_inexact_table, 4014 &xfrm_pol_inexact_params); 4015 BUG_ON(err); 4016 } 4017 4018 hmask = 8 - 1; 4019 sz = (hmask+1) * sizeof(struct hlist_head); 4020 4021 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4022 if (!net->xfrm.policy_byidx) 4023 goto out_byidx; 4024 net->xfrm.policy_idx_hmask = hmask; 4025 4026 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4027 struct xfrm_policy_hash *htab; 4028 4029 net->xfrm.policy_count[dir] = 0; 4030 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4031 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 4032 4033 htab = &net->xfrm.policy_bydst[dir]; 4034 htab->table = xfrm_hash_alloc(sz); 4035 if (!htab->table) 4036 goto out_bydst; 4037 htab->hmask = hmask; 4038 htab->dbits4 = 32; 4039 htab->sbits4 = 32; 4040 htab->dbits6 = 128; 4041 htab->sbits6 = 128; 4042 } 4043 net->xfrm.policy_hthresh.lbits4 = 32; 4044 net->xfrm.policy_hthresh.rbits4 = 32; 4045 net->xfrm.policy_hthresh.lbits6 = 128; 4046 net->xfrm.policy_hthresh.rbits6 = 128; 4047 4048 seqlock_init(&net->xfrm.policy_hthresh.lock); 4049 4050 INIT_LIST_HEAD(&net->xfrm.policy_all); 4051 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4052 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4053 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4054 return 0; 4055 4056 out_bydst: 4057 for (dir--; dir >= 0; dir--) { 4058 struct xfrm_policy_hash *htab; 4059 4060 htab = &net->xfrm.policy_bydst[dir]; 4061 xfrm_hash_free(htab->table, sz); 4062 } 4063 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4064 out_byidx: 4065 return -ENOMEM; 4066 } 4067 4068 static void xfrm_policy_fini(struct net *net) 4069 { 4070 struct xfrm_pol_inexact_bin *b, *t; 4071 unsigned int sz; 4072 int dir; 4073 4074 flush_work(&net->xfrm.policy_hash_work); 4075 #ifdef CONFIG_XFRM_SUB_POLICY 4076 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4077 #endif 4078 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4079 4080 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4081 4082 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4083 struct xfrm_policy_hash *htab; 4084 4085 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 4086 4087 htab = &net->xfrm.policy_bydst[dir]; 4088 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4089 WARN_ON(!hlist_empty(htab->table)); 4090 xfrm_hash_free(htab->table, sz); 4091 } 4092 4093 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4094 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4095 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4096 4097 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4098 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4099 __xfrm_policy_inexact_prune_bin(b, true); 4100 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4101 } 4102 4103 static int __net_init xfrm_net_init(struct net *net) 4104 { 4105 int rv; 4106 4107 /* Initialize the per-net locks here */ 4108 spin_lock_init(&net->xfrm.xfrm_state_lock); 4109 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4110 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4111 4112 rv = xfrm_statistics_init(net); 4113 if (rv < 0) 4114 goto out_statistics; 4115 rv = xfrm_state_init(net); 4116 if (rv < 0) 4117 goto out_state; 4118 rv = xfrm_policy_init(net); 4119 if (rv < 0) 4120 goto out_policy; 4121 rv = xfrm_sysctl_init(net); 4122 if (rv < 0) 4123 goto out_sysctl; 4124 4125 return 0; 4126 4127 out_sysctl: 4128 xfrm_policy_fini(net); 4129 out_policy: 4130 xfrm_state_fini(net); 4131 out_state: 4132 xfrm_statistics_fini(net); 4133 out_statistics: 4134 return rv; 4135 } 4136 4137 static void __net_exit xfrm_net_exit(struct net *net) 4138 { 4139 xfrm_sysctl_fini(net); 4140 xfrm_policy_fini(net); 4141 xfrm_state_fini(net); 4142 xfrm_statistics_fini(net); 4143 } 4144 4145 static struct pernet_operations __net_initdata xfrm_net_ops = { 4146 .init = xfrm_net_init, 4147 .exit = xfrm_net_exit, 4148 }; 4149 4150 void __init xfrm_init(void) 4151 { 4152 register_pernet_subsys(&xfrm_net_ops); 4153 xfrm_dev_init(); 4154 seqcount_init(&xfrm_policy_hash_generation); 4155 xfrm_input_init(); 4156 4157 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4158 synchronize_rcu(); 4159 } 4160 4161 #ifdef CONFIG_AUDITSYSCALL 4162 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4163 struct audit_buffer *audit_buf) 4164 { 4165 struct xfrm_sec_ctx *ctx = xp->security; 4166 struct xfrm_selector *sel = &xp->selector; 4167 4168 if (ctx) 4169 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4170 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4171 4172 switch (sel->family) { 4173 case AF_INET: 4174 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4175 if (sel->prefixlen_s != 32) 4176 audit_log_format(audit_buf, " src_prefixlen=%d", 4177 sel->prefixlen_s); 4178 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4179 if (sel->prefixlen_d != 32) 4180 audit_log_format(audit_buf, " dst_prefixlen=%d", 4181 sel->prefixlen_d); 4182 break; 4183 case AF_INET6: 4184 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4185 if (sel->prefixlen_s != 128) 4186 audit_log_format(audit_buf, " src_prefixlen=%d", 4187 sel->prefixlen_s); 4188 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4189 if (sel->prefixlen_d != 128) 4190 audit_log_format(audit_buf, " dst_prefixlen=%d", 4191 sel->prefixlen_d); 4192 break; 4193 } 4194 } 4195 4196 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4197 { 4198 struct audit_buffer *audit_buf; 4199 4200 audit_buf = xfrm_audit_start("SPD-add"); 4201 if (audit_buf == NULL) 4202 return; 4203 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4204 audit_log_format(audit_buf, " res=%u", result); 4205 xfrm_audit_common_policyinfo(xp, audit_buf); 4206 audit_log_end(audit_buf); 4207 } 4208 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4209 4210 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4211 bool task_valid) 4212 { 4213 struct audit_buffer *audit_buf; 4214 4215 audit_buf = xfrm_audit_start("SPD-delete"); 4216 if (audit_buf == NULL) 4217 return; 4218 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4219 audit_log_format(audit_buf, " res=%u", result); 4220 xfrm_audit_common_policyinfo(xp, audit_buf); 4221 audit_log_end(audit_buf); 4222 } 4223 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4224 #endif 4225 4226 #ifdef CONFIG_XFRM_MIGRATE 4227 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 4228 const struct xfrm_selector *sel_tgt) 4229 { 4230 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 4231 if (sel_tgt->family == sel_cmp->family && 4232 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 4233 sel_cmp->family) && 4234 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 4235 sel_cmp->family) && 4236 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 4237 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 4238 return true; 4239 } 4240 } else { 4241 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 4242 return true; 4243 } 4244 } 4245 return false; 4246 } 4247 4248 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4249 u8 dir, u8 type, struct net *net) 4250 { 4251 struct xfrm_policy *pol, *ret = NULL; 4252 struct hlist_head *chain; 4253 u32 priority = ~0U; 4254 4255 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4256 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 4257 hlist_for_each_entry(pol, chain, bydst) { 4258 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4259 pol->type == type) { 4260 ret = pol; 4261 priority = ret->priority; 4262 break; 4263 } 4264 } 4265 chain = &net->xfrm.policy_inexact[dir]; 4266 hlist_for_each_entry(pol, chain, bydst_inexact_list) { 4267 if ((pol->priority >= priority) && ret) 4268 break; 4269 4270 if (xfrm_migrate_selector_match(sel, &pol->selector) && 4271 pol->type == type) { 4272 ret = pol; 4273 break; 4274 } 4275 } 4276 4277 xfrm_pol_hold(ret); 4278 4279 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4280 4281 return ret; 4282 } 4283 4284 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4285 { 4286 int match = 0; 4287 4288 if (t->mode == m->mode && t->id.proto == m->proto && 4289 (m->reqid == 0 || t->reqid == m->reqid)) { 4290 switch (t->mode) { 4291 case XFRM_MODE_TUNNEL: 4292 case XFRM_MODE_BEET: 4293 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4294 m->old_family) && 4295 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4296 m->old_family)) { 4297 match = 1; 4298 } 4299 break; 4300 case XFRM_MODE_TRANSPORT: 4301 /* in case of transport mode, template does not store 4302 any IP addresses, hence we just compare mode and 4303 protocol */ 4304 match = 1; 4305 break; 4306 default: 4307 break; 4308 } 4309 } 4310 return match; 4311 } 4312 4313 /* update endpoint address(es) of template(s) */ 4314 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4315 struct xfrm_migrate *m, int num_migrate) 4316 { 4317 struct xfrm_migrate *mp; 4318 int i, j, n = 0; 4319 4320 write_lock_bh(&pol->lock); 4321 if (unlikely(pol->walk.dead)) { 4322 /* target policy has been deleted */ 4323 write_unlock_bh(&pol->lock); 4324 return -ENOENT; 4325 } 4326 4327 for (i = 0; i < pol->xfrm_nr; i++) { 4328 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4329 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4330 continue; 4331 n++; 4332 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4333 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4334 continue; 4335 /* update endpoints */ 4336 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4337 sizeof(pol->xfrm_vec[i].id.daddr)); 4338 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4339 sizeof(pol->xfrm_vec[i].saddr)); 4340 pol->xfrm_vec[i].encap_family = mp->new_family; 4341 /* flush bundles */ 4342 atomic_inc(&pol->genid); 4343 } 4344 } 4345 4346 write_unlock_bh(&pol->lock); 4347 4348 if (!n) 4349 return -ENODATA; 4350 4351 return 0; 4352 } 4353 4354 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 4355 { 4356 int i, j; 4357 4358 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 4359 return -EINVAL; 4360 4361 for (i = 0; i < num_migrate; i++) { 4362 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4363 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 4364 return -EINVAL; 4365 4366 /* check if there is any duplicated entry */ 4367 for (j = i + 1; j < num_migrate; j++) { 4368 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4369 sizeof(m[i].old_daddr)) && 4370 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4371 sizeof(m[i].old_saddr)) && 4372 m[i].proto == m[j].proto && 4373 m[i].mode == m[j].mode && 4374 m[i].reqid == m[j].reqid && 4375 m[i].old_family == m[j].old_family) 4376 return -EINVAL; 4377 } 4378 } 4379 4380 return 0; 4381 } 4382 4383 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4384 struct xfrm_migrate *m, int num_migrate, 4385 struct xfrm_kmaddress *k, struct net *net, 4386 struct xfrm_encap_tmpl *encap) 4387 { 4388 int i, err, nx_cur = 0, nx_new = 0; 4389 struct xfrm_policy *pol = NULL; 4390 struct xfrm_state *x, *xc; 4391 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4392 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4393 struct xfrm_migrate *mp; 4394 4395 /* Stage 0 - sanity checks */ 4396 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 4397 goto out; 4398 4399 if (dir >= XFRM_POLICY_MAX) { 4400 err = -EINVAL; 4401 goto out; 4402 } 4403 4404 /* Stage 1 - find policy */ 4405 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 4406 err = -ENOENT; 4407 goto out; 4408 } 4409 4410 /* Stage 2 - find and update state(s) */ 4411 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4412 if ((x = xfrm_migrate_state_find(mp, net))) { 4413 x_cur[nx_cur] = x; 4414 nx_cur++; 4415 xc = xfrm_state_migrate(x, mp, encap); 4416 if (xc) { 4417 x_new[nx_new] = xc; 4418 nx_new++; 4419 } else { 4420 err = -ENODATA; 4421 goto restore_state; 4422 } 4423 } 4424 } 4425 4426 /* Stage 3 - update policy */ 4427 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 4428 goto restore_state; 4429 4430 /* Stage 4 - delete old state(s) */ 4431 if (nx_cur) { 4432 xfrm_states_put(x_cur, nx_cur); 4433 xfrm_states_delete(x_cur, nx_cur); 4434 } 4435 4436 /* Stage 5 - announce */ 4437 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4438 4439 xfrm_pol_put(pol); 4440 4441 return 0; 4442 out: 4443 return err; 4444 4445 restore_state: 4446 if (pol) 4447 xfrm_pol_put(pol); 4448 if (nx_cur) 4449 xfrm_states_put(x_cur, nx_cur); 4450 if (nx_new) 4451 xfrm_states_delete(x_new, nx_new); 4452 4453 return err; 4454 } 4455 EXPORT_SYMBOL(xfrm_migrate); 4456 #endif 4457