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 <linux/icmp.h> 33 #include <net/dst.h> 34 #include <net/flow.h> 35 #include <net/inet_ecn.h> 36 #include <net/xfrm.h> 37 #include <net/ip.h> 38 #include <net/gre.h> 39 #if IS_ENABLED(CONFIG_IPV6_MIP6) 40 #include <net/mip6.h> 41 #endif 42 #ifdef CONFIG_XFRM_STATISTICS 43 #include <net/snmp.h> 44 #endif 45 #ifdef CONFIG_XFRM_ESPINTCP 46 #include <net/espintcp.h> 47 #endif 48 #include <net/inet_dscp.h> 49 50 #include "xfrm_hash.h" 51 52 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 53 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 54 #define XFRM_MAX_QUEUE_LEN 100 55 56 struct xfrm_flo { 57 struct dst_entry *dst_orig; 58 u8 flags; 59 }; 60 61 /* prefixes smaller than this are stored in lists, not trees. */ 62 #define INEXACT_PREFIXLEN_IPV4 16 63 #define INEXACT_PREFIXLEN_IPV6 48 64 65 struct xfrm_pol_inexact_node { 66 struct rb_node node; 67 union { 68 xfrm_address_t addr; 69 struct rcu_head rcu; 70 }; 71 u8 prefixlen; 72 73 struct rb_root root; 74 75 /* the policies matching this node, can be empty list */ 76 struct hlist_head hhead; 77 }; 78 79 /* xfrm inexact policy search tree: 80 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id); 81 * | 82 * +---- root_d: sorted by daddr:prefix 83 * | | 84 * | xfrm_pol_inexact_node 85 * | | 86 * | +- root: sorted by saddr/prefix 87 * | | | 88 * | | xfrm_pol_inexact_node 89 * | | | 90 * | | + root: unused 91 * | | | 92 * | | + hhead: saddr:daddr policies 93 * | | 94 * | +- coarse policies and all any:daddr policies 95 * | 96 * +---- root_s: sorted by saddr:prefix 97 * | | 98 * | xfrm_pol_inexact_node 99 * | | 100 * | + root: unused 101 * | | 102 * | + hhead: saddr:any policies 103 * | 104 * +---- coarse policies and all any:any policies 105 * 106 * Lookups return four candidate lists: 107 * 1. any:any list from top-level xfrm_pol_inexact_bin 108 * 2. any:daddr list from daddr tree 109 * 3. saddr:daddr list from 2nd level daddr tree 110 * 4. saddr:any list from saddr tree 111 * 112 * This result set then needs to be searched for the policy with 113 * the lowest priority. If two candidates have the same priority, the 114 * struct xfrm_policy pos member with the lower number is used. 115 * 116 * This replicates previous single-list-search algorithm which would 117 * return first matching policy in the (ordered-by-priority) list. 118 */ 119 120 struct xfrm_pol_inexact_key { 121 possible_net_t net; 122 u32 if_id; 123 u16 family; 124 u8 dir, type; 125 }; 126 127 struct xfrm_pol_inexact_bin { 128 struct xfrm_pol_inexact_key k; 129 struct rhash_head head; 130 /* list containing '*:*' policies */ 131 struct hlist_head hhead; 132 133 seqcount_spinlock_t count; 134 /* tree sorted by daddr/prefix */ 135 struct rb_root root_d; 136 137 /* tree sorted by saddr/prefix */ 138 struct rb_root root_s; 139 140 /* slow path below */ 141 struct list_head inexact_bins; 142 struct rcu_head rcu; 143 }; 144 145 enum xfrm_pol_inexact_candidate_type { 146 XFRM_POL_CAND_BOTH, 147 XFRM_POL_CAND_SADDR, 148 XFRM_POL_CAND_DADDR, 149 XFRM_POL_CAND_ANY, 150 151 XFRM_POL_CAND_MAX, 152 }; 153 154 struct xfrm_pol_inexact_candidates { 155 struct hlist_head *res[XFRM_POL_CAND_MAX]; 156 }; 157 158 struct xfrm_flow_keys { 159 struct flow_dissector_key_basic basic; 160 struct flow_dissector_key_control control; 161 union { 162 struct flow_dissector_key_ipv4_addrs ipv4; 163 struct flow_dissector_key_ipv6_addrs ipv6; 164 } addrs; 165 struct flow_dissector_key_ip ip; 166 struct flow_dissector_key_icmp icmp; 167 struct flow_dissector_key_ports ports; 168 struct flow_dissector_key_keyid gre; 169 }; 170 171 static struct flow_dissector xfrm_session_dissector __ro_after_init; 172 173 static DEFINE_SPINLOCK(xfrm_if_cb_lock); 174 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 175 176 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 177 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 178 __read_mostly; 179 180 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 181 182 static struct rhashtable xfrm_policy_inexact_table; 183 static const struct rhashtable_params xfrm_pol_inexact_params; 184 185 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 186 static int stale_bundle(struct dst_entry *dst); 187 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 188 static void xfrm_policy_queue_process(struct timer_list *t); 189 190 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 191 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 192 int dir); 193 194 static struct xfrm_pol_inexact_bin * 195 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, 196 u32 if_id); 197 198 static struct xfrm_pol_inexact_bin * 199 xfrm_policy_inexact_lookup_rcu(struct net *net, 200 u8 type, u16 family, u8 dir, u32 if_id); 201 static struct xfrm_policy * 202 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, 203 bool excl); 204 205 static bool 206 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 207 struct xfrm_pol_inexact_bin *b, 208 const xfrm_address_t *saddr, 209 const xfrm_address_t *daddr); 210 xfrm_pol_hold_rcu(struct xfrm_policy * policy)211 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 212 { 213 return refcount_inc_not_zero(&policy->refcnt); 214 } 215 216 static inline bool __xfrm4_selector_match(const struct xfrm_selector * sel,const struct flowi * fl)217 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 218 { 219 const struct flowi4 *fl4 = &fl->u.ip4; 220 221 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 222 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 223 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 224 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 225 (fl4->flowi4_proto == sel->proto || !sel->proto) && 226 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 227 } 228 229 static inline bool __xfrm6_selector_match(const struct xfrm_selector * sel,const struct flowi * fl)230 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 231 { 232 const struct flowi6 *fl6 = &fl->u.ip6; 233 234 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 235 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 236 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 237 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 238 (fl6->flowi6_proto == sel->proto || !sel->proto) && 239 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 240 } 241 xfrm_selector_match(const struct xfrm_selector * sel,const struct flowi * fl,unsigned short family)242 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 243 unsigned short family) 244 { 245 switch (family) { 246 case AF_INET: 247 return __xfrm4_selector_match(sel, fl); 248 case AF_INET6: 249 return __xfrm6_selector_match(sel, fl); 250 } 251 return false; 252 } 253 xfrm_policy_get_afinfo(unsigned short family)254 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 255 { 256 const struct xfrm_policy_afinfo *afinfo; 257 258 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 259 return NULL; 260 rcu_read_lock(); 261 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 262 if (unlikely(!afinfo)) 263 rcu_read_unlock(); 264 return afinfo; 265 } 266 267 /* Called with rcu_read_lock(). */ xfrm_if_get_cb(void)268 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 269 { 270 return rcu_dereference(xfrm_if_cb); 271 } 272 __xfrm_dst_lookup(int family,const struct xfrm_dst_lookup_params * params)273 struct dst_entry *__xfrm_dst_lookup(int family, 274 const struct xfrm_dst_lookup_params *params) 275 { 276 const struct xfrm_policy_afinfo *afinfo; 277 struct dst_entry *dst; 278 279 afinfo = xfrm_policy_get_afinfo(family); 280 if (unlikely(afinfo == NULL)) 281 return ERR_PTR(-EAFNOSUPPORT); 282 283 dst = afinfo->dst_lookup(params); 284 285 rcu_read_unlock(); 286 287 return dst; 288 } 289 EXPORT_SYMBOL(__xfrm_dst_lookup); 290 xfrm_dst_lookup(struct xfrm_state * x,int tos,int oif,xfrm_address_t * prev_saddr,xfrm_address_t * prev_daddr,int family,u32 mark)291 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 292 int tos, int oif, 293 xfrm_address_t *prev_saddr, 294 xfrm_address_t *prev_daddr, 295 int family, u32 mark) 296 { 297 struct xfrm_dst_lookup_params params; 298 struct net *net = xs_net(x); 299 xfrm_address_t *saddr = &x->props.saddr; 300 xfrm_address_t *daddr = &x->id.daddr; 301 struct dst_entry *dst; 302 303 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 304 saddr = x->coaddr; 305 daddr = prev_daddr; 306 } 307 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 308 saddr = prev_saddr; 309 daddr = x->coaddr; 310 } 311 312 params.net = net; 313 params.saddr = saddr; 314 params.daddr = daddr; 315 params.tos = tos; 316 params.oif = oif; 317 params.mark = mark; 318 params.ipproto = x->id.proto; 319 if (x->encap) { 320 switch (x->encap->encap_type) { 321 case UDP_ENCAP_ESPINUDP: 322 params.ipproto = IPPROTO_UDP; 323 params.uli.ports.sport = x->encap->encap_sport; 324 params.uli.ports.dport = x->encap->encap_dport; 325 break; 326 case TCP_ENCAP_ESPINTCP: 327 params.ipproto = IPPROTO_TCP; 328 params.uli.ports.sport = x->encap->encap_sport; 329 params.uli.ports.dport = x->encap->encap_dport; 330 break; 331 } 332 } 333 334 dst = __xfrm_dst_lookup(family, ¶ms); 335 336 if (!IS_ERR(dst)) { 337 if (prev_saddr != saddr) 338 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 339 if (prev_daddr != daddr) 340 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 341 } 342 343 return dst; 344 } 345 make_jiffies(long secs)346 static inline unsigned long make_jiffies(long secs) 347 { 348 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 349 return MAX_SCHEDULE_TIMEOUT-1; 350 else 351 return secs*HZ; 352 } 353 xfrm_policy_timer(struct timer_list * t)354 static void xfrm_policy_timer(struct timer_list *t) 355 { 356 struct xfrm_policy *xp = from_timer(xp, t, timer); 357 time64_t now = ktime_get_real_seconds(); 358 time64_t next = TIME64_MAX; 359 int warn = 0; 360 int dir; 361 362 read_lock(&xp->lock); 363 364 if (unlikely(xp->walk.dead)) 365 goto out; 366 367 dir = xfrm_policy_id2dir(xp->index); 368 369 if (xp->lft.hard_add_expires_seconds) { 370 time64_t tmo = xp->lft.hard_add_expires_seconds + 371 xp->curlft.add_time - now; 372 if (tmo <= 0) 373 goto expired; 374 if (tmo < next) 375 next = tmo; 376 } 377 if (xp->lft.hard_use_expires_seconds) { 378 time64_t tmo = xp->lft.hard_use_expires_seconds + 379 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now; 380 if (tmo <= 0) 381 goto expired; 382 if (tmo < next) 383 next = tmo; 384 } 385 if (xp->lft.soft_add_expires_seconds) { 386 time64_t tmo = xp->lft.soft_add_expires_seconds + 387 xp->curlft.add_time - now; 388 if (tmo <= 0) { 389 warn = 1; 390 tmo = XFRM_KM_TIMEOUT; 391 } 392 if (tmo < next) 393 next = tmo; 394 } 395 if (xp->lft.soft_use_expires_seconds) { 396 time64_t tmo = xp->lft.soft_use_expires_seconds + 397 (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now; 398 if (tmo <= 0) { 399 warn = 1; 400 tmo = XFRM_KM_TIMEOUT; 401 } 402 if (tmo < next) 403 next = tmo; 404 } 405 406 if (warn) 407 km_policy_expired(xp, dir, 0, 0); 408 if (next != TIME64_MAX && 409 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 410 xfrm_pol_hold(xp); 411 412 out: 413 read_unlock(&xp->lock); 414 xfrm_pol_put(xp); 415 return; 416 417 expired: 418 read_unlock(&xp->lock); 419 if (!xfrm_policy_delete(xp, dir)) 420 km_policy_expired(xp, dir, 1, 0); 421 xfrm_pol_put(xp); 422 } 423 424 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 425 * SPD calls. 426 */ 427 xfrm_policy_alloc(struct net * net,gfp_t gfp)428 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 429 { 430 struct xfrm_policy *policy; 431 432 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 433 434 if (policy) { 435 write_pnet(&policy->xp_net, net); 436 INIT_LIST_HEAD(&policy->walk.all); 437 INIT_HLIST_NODE(&policy->bydst); 438 INIT_HLIST_NODE(&policy->byidx); 439 rwlock_init(&policy->lock); 440 refcount_set(&policy->refcnt, 1); 441 skb_queue_head_init(&policy->polq.hold_queue); 442 timer_setup(&policy->timer, xfrm_policy_timer, 0); 443 timer_setup(&policy->polq.hold_timer, 444 xfrm_policy_queue_process, 0); 445 } 446 return policy; 447 } 448 EXPORT_SYMBOL(xfrm_policy_alloc); 449 xfrm_policy_destroy_rcu(struct rcu_head * head)450 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 451 { 452 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 453 454 security_xfrm_policy_free(policy->security); 455 kfree(policy); 456 } 457 458 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 459 xfrm_policy_destroy(struct xfrm_policy * policy)460 void xfrm_policy_destroy(struct xfrm_policy *policy) 461 { 462 BUG_ON(!policy->walk.dead); 463 464 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 465 BUG(); 466 467 xfrm_dev_policy_free(policy); 468 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 469 } 470 EXPORT_SYMBOL(xfrm_policy_destroy); 471 472 /* Rule must be locked. Release descendant resources, announce 473 * entry dead. The rule must be unlinked from lists to the moment. 474 */ 475 xfrm_policy_kill(struct xfrm_policy * policy)476 static void xfrm_policy_kill(struct xfrm_policy *policy) 477 { 478 xfrm_dev_policy_delete(policy); 479 480 write_lock_bh(&policy->lock); 481 policy->walk.dead = 1; 482 write_unlock_bh(&policy->lock); 483 484 atomic_inc(&policy->genid); 485 486 if (del_timer(&policy->polq.hold_timer)) 487 xfrm_pol_put(policy); 488 skb_queue_purge(&policy->polq.hold_queue); 489 490 if (del_timer(&policy->timer)) 491 xfrm_pol_put(policy); 492 493 xfrm_pol_put(policy); 494 } 495 496 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 497 idx_hash(struct net * net,u32 index)498 static inline unsigned int idx_hash(struct net *net, u32 index) 499 { 500 return __idx_hash(index, net->xfrm.policy_idx_hmask); 501 } 502 503 /* calculate policy hash thresholds */ __get_hash_thresh(struct net * net,unsigned short family,int dir,u8 * dbits,u8 * sbits)504 static void __get_hash_thresh(struct net *net, 505 unsigned short family, int dir, 506 u8 *dbits, u8 *sbits) 507 { 508 switch (family) { 509 case AF_INET: 510 *dbits = net->xfrm.policy_bydst[dir].dbits4; 511 *sbits = net->xfrm.policy_bydst[dir].sbits4; 512 break; 513 514 case AF_INET6: 515 *dbits = net->xfrm.policy_bydst[dir].dbits6; 516 *sbits = net->xfrm.policy_bydst[dir].sbits6; 517 break; 518 519 default: 520 *dbits = 0; 521 *sbits = 0; 522 } 523 } 524 policy_hash_bysel(struct net * net,const struct xfrm_selector * sel,unsigned short family,int dir)525 static struct hlist_head *policy_hash_bysel(struct net *net, 526 const struct xfrm_selector *sel, 527 unsigned short family, int dir) 528 { 529 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 530 unsigned int hash; 531 u8 dbits; 532 u8 sbits; 533 534 __get_hash_thresh(net, family, dir, &dbits, &sbits); 535 hash = __sel_hash(sel, family, hmask, dbits, sbits); 536 537 if (hash == hmask + 1) 538 return NULL; 539 540 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 541 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 542 } 543 policy_hash_direct(struct net * net,const xfrm_address_t * daddr,const xfrm_address_t * saddr,unsigned short family,int dir)544 static struct hlist_head *policy_hash_direct(struct net *net, 545 const xfrm_address_t *daddr, 546 const xfrm_address_t *saddr, 547 unsigned short family, int dir) 548 { 549 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 550 unsigned int hash; 551 u8 dbits; 552 u8 sbits; 553 554 __get_hash_thresh(net, family, dir, &dbits, &sbits); 555 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 556 557 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 558 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 559 } 560 xfrm_dst_hash_transfer(struct net * net,struct hlist_head * list,struct hlist_head * ndsttable,unsigned int nhashmask,int dir)561 static void xfrm_dst_hash_transfer(struct net *net, 562 struct hlist_head *list, 563 struct hlist_head *ndsttable, 564 unsigned int nhashmask, 565 int dir) 566 { 567 struct hlist_node *tmp, *entry0 = NULL; 568 struct xfrm_policy *pol; 569 unsigned int h0 = 0; 570 u8 dbits; 571 u8 sbits; 572 573 redo: 574 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 575 unsigned int h; 576 577 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 578 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 579 pol->family, nhashmask, dbits, sbits); 580 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) { 581 hlist_del_rcu(&pol->bydst); 582 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 583 h0 = h; 584 } else { 585 if (h != h0) 586 continue; 587 hlist_del_rcu(&pol->bydst); 588 hlist_add_behind_rcu(&pol->bydst, entry0); 589 } 590 entry0 = &pol->bydst; 591 } 592 if (!hlist_empty(list)) { 593 entry0 = NULL; 594 goto redo; 595 } 596 } 597 xfrm_idx_hash_transfer(struct hlist_head * list,struct hlist_head * nidxtable,unsigned int nhashmask)598 static void xfrm_idx_hash_transfer(struct hlist_head *list, 599 struct hlist_head *nidxtable, 600 unsigned int nhashmask) 601 { 602 struct hlist_node *tmp; 603 struct xfrm_policy *pol; 604 605 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 606 unsigned int h; 607 608 h = __idx_hash(pol->index, nhashmask); 609 hlist_add_head(&pol->byidx, nidxtable+h); 610 } 611 } 612 xfrm_new_hash_mask(unsigned int old_hmask)613 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 614 { 615 return ((old_hmask + 1) << 1) - 1; 616 } 617 xfrm_bydst_resize(struct net * net,int dir)618 static void xfrm_bydst_resize(struct net *net, int dir) 619 { 620 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 621 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 622 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 623 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 624 struct hlist_head *odst; 625 int i; 626 627 if (!ndst) 628 return; 629 630 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 631 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 632 633 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 634 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 635 636 for (i = hmask; i >= 0; i--) 637 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 638 639 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 640 net->xfrm.policy_bydst[dir].hmask = nhashmask; 641 642 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 643 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 644 645 synchronize_rcu(); 646 647 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 648 } 649 xfrm_byidx_resize(struct net * net)650 static void xfrm_byidx_resize(struct net *net) 651 { 652 unsigned int hmask = net->xfrm.policy_idx_hmask; 653 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 654 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 655 struct hlist_head *oidx = net->xfrm.policy_byidx; 656 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 657 int i; 658 659 if (!nidx) 660 return; 661 662 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 663 664 for (i = hmask; i >= 0; i--) 665 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 666 667 net->xfrm.policy_byidx = nidx; 668 net->xfrm.policy_idx_hmask = nhashmask; 669 670 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 671 672 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 673 } 674 xfrm_bydst_should_resize(struct net * net,int dir,int * total)675 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 676 { 677 unsigned int cnt = net->xfrm.policy_count[dir]; 678 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 679 680 if (total) 681 *total += cnt; 682 683 if ((hmask + 1) < xfrm_policy_hashmax && 684 cnt > hmask) 685 return 1; 686 687 return 0; 688 } 689 xfrm_byidx_should_resize(struct net * net,int total)690 static inline int xfrm_byidx_should_resize(struct net *net, int total) 691 { 692 unsigned int hmask = net->xfrm.policy_idx_hmask; 693 694 if ((hmask + 1) < xfrm_policy_hashmax && 695 total > hmask) 696 return 1; 697 698 return 0; 699 } 700 xfrm_spd_getinfo(struct net * net,struct xfrmk_spdinfo * si)701 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 702 { 703 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 704 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 705 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 706 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 707 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 708 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 709 si->spdhcnt = net->xfrm.policy_idx_hmask; 710 si->spdhmcnt = xfrm_policy_hashmax; 711 } 712 EXPORT_SYMBOL(xfrm_spd_getinfo); 713 714 static DEFINE_MUTEX(hash_resize_mutex); xfrm_hash_resize(struct work_struct * work)715 static void xfrm_hash_resize(struct work_struct *work) 716 { 717 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 718 int dir, total; 719 720 mutex_lock(&hash_resize_mutex); 721 722 total = 0; 723 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 724 if (xfrm_bydst_should_resize(net, dir, &total)) 725 xfrm_bydst_resize(net, dir); 726 } 727 if (xfrm_byidx_should_resize(net, total)) 728 xfrm_byidx_resize(net); 729 730 mutex_unlock(&hash_resize_mutex); 731 } 732 733 /* Make sure *pol can be inserted into fastbin. 734 * Useful to check that later insert requests will be successful 735 * (provided xfrm_policy_lock is held throughout). 736 */ 737 static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_alloc_bin(const struct xfrm_policy * pol,u8 dir)738 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) 739 { 740 struct xfrm_pol_inexact_bin *bin, *prev; 741 struct xfrm_pol_inexact_key k = { 742 .family = pol->family, 743 .type = pol->type, 744 .dir = dir, 745 .if_id = pol->if_id, 746 }; 747 struct net *net = xp_net(pol); 748 749 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 750 751 write_pnet(&k.net, net); 752 bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, 753 xfrm_pol_inexact_params); 754 if (bin) 755 return bin; 756 757 bin = kzalloc(sizeof(*bin), GFP_ATOMIC); 758 if (!bin) 759 return NULL; 760 761 bin->k = k; 762 INIT_HLIST_HEAD(&bin->hhead); 763 bin->root_d = RB_ROOT; 764 bin->root_s = RB_ROOT; 765 seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); 766 767 prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, 768 &bin->k, &bin->head, 769 xfrm_pol_inexact_params); 770 if (!prev) { 771 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); 772 return bin; 773 } 774 775 kfree(bin); 776 777 return IS_ERR(prev) ? NULL : prev; 778 } 779 xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t * addr,int family,u8 prefixlen)780 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, 781 int family, u8 prefixlen) 782 { 783 if (xfrm_addr_any(addr, family)) 784 return true; 785 786 if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) 787 return true; 788 789 if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) 790 return true; 791 792 return false; 793 } 794 795 static bool xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy * policy)796 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) 797 { 798 const xfrm_address_t *addr; 799 bool saddr_any, daddr_any; 800 u8 prefixlen; 801 802 addr = &policy->selector.saddr; 803 prefixlen = policy->selector.prefixlen_s; 804 805 saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 806 policy->family, 807 prefixlen); 808 addr = &policy->selector.daddr; 809 prefixlen = policy->selector.prefixlen_d; 810 daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, 811 policy->family, 812 prefixlen); 813 return saddr_any && daddr_any; 814 } 815 xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node * node,const xfrm_address_t * addr,u8 prefixlen)816 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, 817 const xfrm_address_t *addr, u8 prefixlen) 818 { 819 node->addr = *addr; 820 node->prefixlen = prefixlen; 821 } 822 823 static struct xfrm_pol_inexact_node * xfrm_pol_inexact_node_alloc(const xfrm_address_t * addr,u8 prefixlen)824 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) 825 { 826 struct xfrm_pol_inexact_node *node; 827 828 node = kzalloc(sizeof(*node), GFP_ATOMIC); 829 if (node) 830 xfrm_pol_inexact_node_init(node, addr, prefixlen); 831 832 return node; 833 } 834 xfrm_policy_addr_delta(const xfrm_address_t * a,const xfrm_address_t * b,u8 prefixlen,u16 family)835 static int xfrm_policy_addr_delta(const xfrm_address_t *a, 836 const xfrm_address_t *b, 837 u8 prefixlen, u16 family) 838 { 839 u32 ma, mb, mask; 840 unsigned int pdw, pbi; 841 int delta = 0; 842 843 switch (family) { 844 case AF_INET: 845 if (prefixlen == 0) 846 return 0; 847 mask = ~0U << (32 - prefixlen); 848 ma = ntohl(a->a4) & mask; 849 mb = ntohl(b->a4) & mask; 850 if (ma < mb) 851 delta = -1; 852 else if (ma > mb) 853 delta = 1; 854 break; 855 case AF_INET6: 856 pdw = prefixlen >> 5; 857 pbi = prefixlen & 0x1f; 858 859 if (pdw) { 860 delta = memcmp(a->a6, b->a6, pdw << 2); 861 if (delta) 862 return delta; 863 } 864 if (pbi) { 865 mask = ~0U << (32 - pbi); 866 ma = ntohl(a->a6[pdw]) & mask; 867 mb = ntohl(b->a6[pdw]) & mask; 868 if (ma < mb) 869 delta = -1; 870 else if (ma > mb) 871 delta = 1; 872 } 873 break; 874 default: 875 break; 876 } 877 878 return delta; 879 } 880 xfrm_policy_inexact_list_reinsert(struct net * net,struct xfrm_pol_inexact_node * n,u16 family)881 static void xfrm_policy_inexact_list_reinsert(struct net *net, 882 struct xfrm_pol_inexact_node *n, 883 u16 family) 884 { 885 unsigned int matched_s, matched_d; 886 struct xfrm_policy *policy, *p; 887 888 matched_s = 0; 889 matched_d = 0; 890 891 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 892 struct hlist_node *newpos = NULL; 893 bool matches_s, matches_d; 894 895 if (policy->walk.dead || !policy->bydst_reinsert) 896 continue; 897 898 WARN_ON_ONCE(policy->family != family); 899 900 policy->bydst_reinsert = false; 901 hlist_for_each_entry(p, &n->hhead, bydst) { 902 if (policy->priority > p->priority) 903 newpos = &p->bydst; 904 else if (policy->priority == p->priority && 905 policy->pos > p->pos) 906 newpos = &p->bydst; 907 else 908 break; 909 } 910 911 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 912 hlist_add_behind_rcu(&policy->bydst, newpos); 913 else 914 hlist_add_head_rcu(&policy->bydst, &n->hhead); 915 916 /* paranoia checks follow. 917 * Check that the reinserted policy matches at least 918 * saddr or daddr for current node prefix. 919 * 920 * Matching both is fine, matching saddr in one policy 921 * (but not daddr) and then matching only daddr in another 922 * is a bug. 923 */ 924 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, 925 &n->addr, 926 n->prefixlen, 927 family) == 0; 928 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, 929 &n->addr, 930 n->prefixlen, 931 family) == 0; 932 if (matches_s && matches_d) 933 continue; 934 935 WARN_ON_ONCE(!matches_s && !matches_d); 936 if (matches_s) 937 matched_s++; 938 if (matches_d) 939 matched_d++; 940 WARN_ON_ONCE(matched_s && matched_d); 941 } 942 } 943 xfrm_policy_inexact_node_reinsert(struct net * net,struct xfrm_pol_inexact_node * n,struct rb_root * new,u16 family)944 static void xfrm_policy_inexact_node_reinsert(struct net *net, 945 struct xfrm_pol_inexact_node *n, 946 struct rb_root *new, 947 u16 family) 948 { 949 struct xfrm_pol_inexact_node *node; 950 struct rb_node **p, *parent; 951 952 /* we should not have another subtree here */ 953 WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); 954 restart: 955 parent = NULL; 956 p = &new->rb_node; 957 while (*p) { 958 u8 prefixlen; 959 int delta; 960 961 parent = *p; 962 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 963 964 prefixlen = min(node->prefixlen, n->prefixlen); 965 966 delta = xfrm_policy_addr_delta(&n->addr, &node->addr, 967 prefixlen, family); 968 if (delta < 0) { 969 p = &parent->rb_left; 970 } else if (delta > 0) { 971 p = &parent->rb_right; 972 } else { 973 bool same_prefixlen = node->prefixlen == n->prefixlen; 974 struct xfrm_policy *tmp; 975 976 hlist_for_each_entry(tmp, &n->hhead, bydst) { 977 tmp->bydst_reinsert = true; 978 hlist_del_rcu(&tmp->bydst); 979 } 980 981 node->prefixlen = prefixlen; 982 983 xfrm_policy_inexact_list_reinsert(net, node, family); 984 985 if (same_prefixlen) { 986 kfree_rcu(n, rcu); 987 return; 988 } 989 990 rb_erase(*p, new); 991 kfree_rcu(n, rcu); 992 n = node; 993 goto restart; 994 } 995 } 996 997 rb_link_node_rcu(&n->node, parent, p); 998 rb_insert_color(&n->node, new); 999 } 1000 1001 /* merge nodes v and n */ xfrm_policy_inexact_node_merge(struct net * net,struct xfrm_pol_inexact_node * v,struct xfrm_pol_inexact_node * n,u16 family)1002 static void xfrm_policy_inexact_node_merge(struct net *net, 1003 struct xfrm_pol_inexact_node *v, 1004 struct xfrm_pol_inexact_node *n, 1005 u16 family) 1006 { 1007 struct xfrm_pol_inexact_node *node; 1008 struct xfrm_policy *tmp; 1009 struct rb_node *rnode; 1010 1011 /* To-be-merged node v has a subtree. 1012 * 1013 * Dismantle it and insert its nodes to n->root. 1014 */ 1015 while ((rnode = rb_first(&v->root)) != NULL) { 1016 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); 1017 rb_erase(&node->node, &v->root); 1018 xfrm_policy_inexact_node_reinsert(net, node, &n->root, 1019 family); 1020 } 1021 1022 hlist_for_each_entry(tmp, &v->hhead, bydst) { 1023 tmp->bydst_reinsert = true; 1024 hlist_del_rcu(&tmp->bydst); 1025 } 1026 1027 xfrm_policy_inexact_list_reinsert(net, n, family); 1028 } 1029 1030 static struct xfrm_pol_inexact_node * xfrm_policy_inexact_insert_node(struct net * net,struct rb_root * root,xfrm_address_t * addr,u16 family,u8 prefixlen,u8 dir)1031 xfrm_policy_inexact_insert_node(struct net *net, 1032 struct rb_root *root, 1033 xfrm_address_t *addr, 1034 u16 family, u8 prefixlen, u8 dir) 1035 { 1036 struct xfrm_pol_inexact_node *cached = NULL; 1037 struct rb_node **p, *parent = NULL; 1038 struct xfrm_pol_inexact_node *node; 1039 1040 p = &root->rb_node; 1041 while (*p) { 1042 int delta; 1043 1044 parent = *p; 1045 node = rb_entry(*p, struct xfrm_pol_inexact_node, node); 1046 1047 delta = xfrm_policy_addr_delta(addr, &node->addr, 1048 node->prefixlen, 1049 family); 1050 if (delta == 0 && prefixlen >= node->prefixlen) { 1051 WARN_ON_ONCE(cached); /* ipsec policies got lost */ 1052 return node; 1053 } 1054 1055 if (delta < 0) 1056 p = &parent->rb_left; 1057 else 1058 p = &parent->rb_right; 1059 1060 if (prefixlen < node->prefixlen) { 1061 delta = xfrm_policy_addr_delta(addr, &node->addr, 1062 prefixlen, 1063 family); 1064 if (delta) 1065 continue; 1066 1067 /* This node is a subnet of the new prefix. It needs 1068 * to be removed and re-inserted with the smaller 1069 * prefix and all nodes that are now also covered 1070 * by the reduced prefixlen. 1071 */ 1072 rb_erase(&node->node, root); 1073 1074 if (!cached) { 1075 xfrm_pol_inexact_node_init(node, addr, 1076 prefixlen); 1077 cached = node; 1078 } else { 1079 /* This node also falls within the new 1080 * prefixlen. Merge the to-be-reinserted 1081 * node and this one. 1082 */ 1083 xfrm_policy_inexact_node_merge(net, node, 1084 cached, family); 1085 kfree_rcu(node, rcu); 1086 } 1087 1088 /* restart */ 1089 p = &root->rb_node; 1090 parent = NULL; 1091 } 1092 } 1093 1094 node = cached; 1095 if (!node) { 1096 node = xfrm_pol_inexact_node_alloc(addr, prefixlen); 1097 if (!node) 1098 return NULL; 1099 } 1100 1101 rb_link_node_rcu(&node->node, parent, p); 1102 rb_insert_color(&node->node, root); 1103 1104 return node; 1105 } 1106 xfrm_policy_inexact_gc_tree(struct rb_root * r,bool rm)1107 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) 1108 { 1109 struct xfrm_pol_inexact_node *node; 1110 struct rb_node *rn = rb_first(r); 1111 1112 while (rn) { 1113 node = rb_entry(rn, struct xfrm_pol_inexact_node, node); 1114 1115 xfrm_policy_inexact_gc_tree(&node->root, rm); 1116 rn = rb_next(rn); 1117 1118 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { 1119 WARN_ON_ONCE(rm); 1120 continue; 1121 } 1122 1123 rb_erase(&node->node, r); 1124 kfree_rcu(node, rcu); 1125 } 1126 } 1127 __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin * b,bool net_exit)1128 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) 1129 { 1130 write_seqcount_begin(&b->count); 1131 xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); 1132 xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); 1133 write_seqcount_end(&b->count); 1134 1135 if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || 1136 !hlist_empty(&b->hhead)) { 1137 WARN_ON_ONCE(net_exit); 1138 return; 1139 } 1140 1141 if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, 1142 xfrm_pol_inexact_params) == 0) { 1143 list_del(&b->inexact_bins); 1144 kfree_rcu(b, rcu); 1145 } 1146 } 1147 xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin * b)1148 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) 1149 { 1150 struct net *net = read_pnet(&b->k.net); 1151 1152 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1153 __xfrm_policy_inexact_prune_bin(b, false); 1154 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1155 } 1156 __xfrm_policy_inexact_flush(struct net * net)1157 static void __xfrm_policy_inexact_flush(struct net *net) 1158 { 1159 struct xfrm_pol_inexact_bin *bin, *t; 1160 1161 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1162 1163 list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) 1164 __xfrm_policy_inexact_prune_bin(bin, false); 1165 } 1166 1167 static struct hlist_head * xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin * bin,struct xfrm_policy * policy,u8 dir)1168 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, 1169 struct xfrm_policy *policy, u8 dir) 1170 { 1171 struct xfrm_pol_inexact_node *n; 1172 struct net *net; 1173 1174 net = xp_net(policy); 1175 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1176 1177 if (xfrm_policy_inexact_insert_use_any_list(policy)) 1178 return &bin->hhead; 1179 1180 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, 1181 policy->family, 1182 policy->selector.prefixlen_d)) { 1183 write_seqcount_begin(&bin->count); 1184 n = xfrm_policy_inexact_insert_node(net, 1185 &bin->root_s, 1186 &policy->selector.saddr, 1187 policy->family, 1188 policy->selector.prefixlen_s, 1189 dir); 1190 write_seqcount_end(&bin->count); 1191 if (!n) 1192 return NULL; 1193 1194 return &n->hhead; 1195 } 1196 1197 /* daddr is fixed */ 1198 write_seqcount_begin(&bin->count); 1199 n = xfrm_policy_inexact_insert_node(net, 1200 &bin->root_d, 1201 &policy->selector.daddr, 1202 policy->family, 1203 policy->selector.prefixlen_d, dir); 1204 write_seqcount_end(&bin->count); 1205 if (!n) 1206 return NULL; 1207 1208 /* saddr is wildcard */ 1209 if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, 1210 policy->family, 1211 policy->selector.prefixlen_s)) 1212 return &n->hhead; 1213 1214 write_seqcount_begin(&bin->count); 1215 n = xfrm_policy_inexact_insert_node(net, 1216 &n->root, 1217 &policy->selector.saddr, 1218 policy->family, 1219 policy->selector.prefixlen_s, dir); 1220 write_seqcount_end(&bin->count); 1221 if (!n) 1222 return NULL; 1223 1224 return &n->hhead; 1225 } 1226 1227 static struct xfrm_policy * xfrm_policy_inexact_insert(struct xfrm_policy * policy,u8 dir,int excl)1228 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) 1229 { 1230 struct xfrm_pol_inexact_bin *bin; 1231 struct xfrm_policy *delpol; 1232 struct hlist_head *chain; 1233 struct net *net; 1234 1235 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1236 if (!bin) 1237 return ERR_PTR(-ENOMEM); 1238 1239 net = xp_net(policy); 1240 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 1241 1242 chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); 1243 if (!chain) { 1244 __xfrm_policy_inexact_prune_bin(bin, false); 1245 return ERR_PTR(-ENOMEM); 1246 } 1247 1248 delpol = xfrm_policy_insert_list(chain, policy, excl); 1249 if (delpol && excl) { 1250 __xfrm_policy_inexact_prune_bin(bin, false); 1251 return ERR_PTR(-EEXIST); 1252 } 1253 1254 if (delpol) 1255 __xfrm_policy_inexact_prune_bin(bin, false); 1256 1257 return delpol; 1258 } 1259 xfrm_policy_is_dead_or_sk(const struct xfrm_policy * policy)1260 static bool xfrm_policy_is_dead_or_sk(const struct xfrm_policy *policy) 1261 { 1262 int dir; 1263 1264 if (policy->walk.dead) 1265 return true; 1266 1267 dir = xfrm_policy_id2dir(policy->index); 1268 return dir >= XFRM_POLICY_MAX; 1269 } 1270 xfrm_hash_rebuild(struct work_struct * work)1271 static void xfrm_hash_rebuild(struct work_struct *work) 1272 { 1273 struct net *net = container_of(work, struct net, 1274 xfrm.policy_hthresh.work); 1275 struct xfrm_policy *pol; 1276 struct xfrm_policy *policy; 1277 struct hlist_head *chain; 1278 struct hlist_node *newpos; 1279 int dir; 1280 unsigned seq; 1281 u8 lbits4, rbits4, lbits6, rbits6; 1282 1283 mutex_lock(&hash_resize_mutex); 1284 1285 /* read selector prefixlen thresholds */ 1286 do { 1287 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 1288 1289 lbits4 = net->xfrm.policy_hthresh.lbits4; 1290 rbits4 = net->xfrm.policy_hthresh.rbits4; 1291 lbits6 = net->xfrm.policy_hthresh.lbits6; 1292 rbits6 = net->xfrm.policy_hthresh.rbits6; 1293 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 1294 1295 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1296 write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 1297 1298 /* make sure that we can insert the indirect policies again before 1299 * we start with destructive action. 1300 */ 1301 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 1302 struct xfrm_pol_inexact_bin *bin; 1303 u8 dbits, sbits; 1304 1305 if (xfrm_policy_is_dead_or_sk(policy)) 1306 continue; 1307 1308 dir = xfrm_policy_id2dir(policy->index); 1309 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1310 if (policy->family == AF_INET) { 1311 dbits = rbits4; 1312 sbits = lbits4; 1313 } else { 1314 dbits = rbits6; 1315 sbits = lbits6; 1316 } 1317 } else { 1318 if (policy->family == AF_INET) { 1319 dbits = lbits4; 1320 sbits = rbits4; 1321 } else { 1322 dbits = lbits6; 1323 sbits = rbits6; 1324 } 1325 } 1326 1327 if (policy->selector.prefixlen_d < dbits || 1328 policy->selector.prefixlen_s < sbits) 1329 continue; 1330 1331 bin = xfrm_policy_inexact_alloc_bin(policy, dir); 1332 if (!bin) 1333 goto out_unlock; 1334 1335 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir)) 1336 goto out_unlock; 1337 } 1338 1339 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 1340 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 1341 /* dir out => dst = remote, src = local */ 1342 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 1343 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 1344 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 1345 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 1346 } else { 1347 /* dir in/fwd => dst = local, src = remote */ 1348 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 1349 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 1350 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 1351 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 1352 } 1353 } 1354 1355 /* re-insert all policies by order of creation */ 1356 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 1357 if (xfrm_policy_is_dead_or_sk(policy)) 1358 continue; 1359 1360 hlist_del_rcu(&policy->bydst); 1361 1362 newpos = NULL; 1363 dir = xfrm_policy_id2dir(policy->index); 1364 chain = policy_hash_bysel(net, &policy->selector, 1365 policy->family, dir); 1366 1367 if (!chain) { 1368 void *p = xfrm_policy_inexact_insert(policy, dir, 0); 1369 1370 WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p)); 1371 continue; 1372 } 1373 1374 hlist_for_each_entry(pol, chain, bydst) { 1375 if (policy->priority >= pol->priority) 1376 newpos = &pol->bydst; 1377 else 1378 break; 1379 } 1380 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1381 hlist_add_behind_rcu(&policy->bydst, newpos); 1382 else 1383 hlist_add_head_rcu(&policy->bydst, chain); 1384 } 1385 1386 out_unlock: 1387 __xfrm_policy_inexact_flush(net); 1388 write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); 1389 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1390 1391 mutex_unlock(&hash_resize_mutex); 1392 } 1393 xfrm_policy_hash_rebuild(struct net * net)1394 void xfrm_policy_hash_rebuild(struct net *net) 1395 { 1396 schedule_work(&net->xfrm.policy_hthresh.work); 1397 } 1398 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 1399 1400 /* Generate new index... KAME seems to generate them ordered by cost 1401 * of an absolute inpredictability of ordering of rules. This will not pass. */ xfrm_gen_index(struct net * net,int dir,u32 index)1402 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 1403 { 1404 for (;;) { 1405 struct hlist_head *list; 1406 struct xfrm_policy *p; 1407 u32 idx; 1408 int found; 1409 1410 if (!index) { 1411 idx = (net->xfrm.idx_generator | dir); 1412 net->xfrm.idx_generator += 8; 1413 } else { 1414 idx = index; 1415 index = 0; 1416 } 1417 1418 if (idx == 0) 1419 idx = 8; 1420 list = net->xfrm.policy_byidx + idx_hash(net, idx); 1421 found = 0; 1422 hlist_for_each_entry(p, list, byidx) { 1423 if (p->index == idx) { 1424 found = 1; 1425 break; 1426 } 1427 } 1428 if (!found) 1429 return idx; 1430 } 1431 } 1432 selector_cmp(struct xfrm_selector * s1,struct xfrm_selector * s2)1433 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 1434 { 1435 u32 *p1 = (u32 *) s1; 1436 u32 *p2 = (u32 *) s2; 1437 int len = sizeof(struct xfrm_selector) / sizeof(u32); 1438 int i; 1439 1440 for (i = 0; i < len; i++) { 1441 if (p1[i] != p2[i]) 1442 return 1; 1443 } 1444 1445 return 0; 1446 } 1447 xfrm_policy_requeue(struct xfrm_policy * old,struct xfrm_policy * new)1448 static void xfrm_policy_requeue(struct xfrm_policy *old, 1449 struct xfrm_policy *new) 1450 { 1451 struct xfrm_policy_queue *pq = &old->polq; 1452 struct sk_buff_head list; 1453 1454 if (skb_queue_empty(&pq->hold_queue)) 1455 return; 1456 1457 __skb_queue_head_init(&list); 1458 1459 spin_lock_bh(&pq->hold_queue.lock); 1460 skb_queue_splice_init(&pq->hold_queue, &list); 1461 if (del_timer(&pq->hold_timer)) 1462 xfrm_pol_put(old); 1463 spin_unlock_bh(&pq->hold_queue.lock); 1464 1465 pq = &new->polq; 1466 1467 spin_lock_bh(&pq->hold_queue.lock); 1468 skb_queue_splice(&list, &pq->hold_queue); 1469 pq->timeout = XFRM_QUEUE_TMO_MIN; 1470 if (!mod_timer(&pq->hold_timer, jiffies)) 1471 xfrm_pol_hold(new); 1472 spin_unlock_bh(&pq->hold_queue.lock); 1473 } 1474 xfrm_policy_mark_match(const struct xfrm_mark * mark,struct xfrm_policy * pol)1475 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark, 1476 struct xfrm_policy *pol) 1477 { 1478 return mark->v == pol->mark.v && mark->m == pol->mark.m; 1479 } 1480 xfrm_pol_bin_key(const void * data,u32 len,u32 seed)1481 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) 1482 { 1483 const struct xfrm_pol_inexact_key *k = data; 1484 u32 a = k->type << 24 | k->dir << 16 | k->family; 1485 1486 return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), 1487 seed); 1488 } 1489 xfrm_pol_bin_obj(const void * data,u32 len,u32 seed)1490 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) 1491 { 1492 const struct xfrm_pol_inexact_bin *b = data; 1493 1494 return xfrm_pol_bin_key(&b->k, 0, seed); 1495 } 1496 xfrm_pol_bin_cmp(struct rhashtable_compare_arg * arg,const void * ptr)1497 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, 1498 const void *ptr) 1499 { 1500 const struct xfrm_pol_inexact_key *key = arg->key; 1501 const struct xfrm_pol_inexact_bin *b = ptr; 1502 int ret; 1503 1504 if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) 1505 return -1; 1506 1507 ret = b->k.dir ^ key->dir; 1508 if (ret) 1509 return ret; 1510 1511 ret = b->k.type ^ key->type; 1512 if (ret) 1513 return ret; 1514 1515 ret = b->k.family ^ key->family; 1516 if (ret) 1517 return ret; 1518 1519 return b->k.if_id ^ key->if_id; 1520 } 1521 1522 static const struct rhashtable_params xfrm_pol_inexact_params = { 1523 .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), 1524 .hashfn = xfrm_pol_bin_key, 1525 .obj_hashfn = xfrm_pol_bin_obj, 1526 .obj_cmpfn = xfrm_pol_bin_cmp, 1527 .automatic_shrinking = true, 1528 }; 1529 xfrm_policy_insert_list(struct hlist_head * chain,struct xfrm_policy * policy,bool excl)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->mark, 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 && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 1557 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); 1558 else 1559 /* Packet offload policies enter to the head 1560 * to speed-up lookups. 1561 */ 1562 hlist_add_head_rcu(&policy->bydst, chain); 1563 1564 return delpol; 1565 } 1566 xfrm_policy_insert(int dir,struct xfrm_policy * policy,int excl)1567 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 1568 { 1569 struct net *net = xp_net(policy); 1570 struct xfrm_policy *delpol; 1571 struct hlist_head *chain; 1572 1573 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1574 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 1575 if (chain) 1576 delpol = xfrm_policy_insert_list(chain, policy, excl); 1577 else 1578 delpol = xfrm_policy_inexact_insert(policy, dir, excl); 1579 1580 if (IS_ERR(delpol)) { 1581 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1582 return PTR_ERR(delpol); 1583 } 1584 1585 __xfrm_policy_link(policy, dir); 1586 1587 /* After previous checking, family can either be AF_INET or AF_INET6 */ 1588 if (policy->family == AF_INET) 1589 rt_genid_bump_ipv4(net); 1590 else 1591 rt_genid_bump_ipv6(net); 1592 1593 if (delpol) { 1594 xfrm_policy_requeue(delpol, policy); 1595 __xfrm_policy_unlink(delpol, dir); 1596 } 1597 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 1598 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 1599 policy->curlft.add_time = ktime_get_real_seconds(); 1600 policy->curlft.use_time = 0; 1601 if (!mod_timer(&policy->timer, jiffies + HZ)) 1602 xfrm_pol_hold(policy); 1603 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1604 1605 if (delpol) 1606 xfrm_policy_kill(delpol); 1607 else if (xfrm_bydst_should_resize(net, dir, NULL)) 1608 schedule_work(&net->xfrm.policy_hash_work); 1609 1610 return 0; 1611 } 1612 EXPORT_SYMBOL(xfrm_policy_insert); 1613 1614 static struct xfrm_policy * __xfrm_policy_bysel_ctx(struct hlist_head * chain,const struct xfrm_mark * mark,u32 if_id,u8 type,int dir,struct xfrm_selector * sel,struct xfrm_sec_ctx * ctx)1615 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark, 1616 u32 if_id, u8 type, int dir, struct xfrm_selector *sel, 1617 struct xfrm_sec_ctx *ctx) 1618 { 1619 struct xfrm_policy *pol; 1620 1621 if (!chain) 1622 return NULL; 1623 1624 hlist_for_each_entry(pol, chain, bydst) { 1625 if (pol->type == type && 1626 pol->if_id == if_id && 1627 xfrm_policy_mark_match(mark, pol) && 1628 !selector_cmp(sel, &pol->selector) && 1629 xfrm_sec_ctx_match(ctx, pol->security)) 1630 return pol; 1631 } 1632 1633 return NULL; 1634 } 1635 1636 struct xfrm_policy * xfrm_policy_bysel_ctx(struct net * net,const struct xfrm_mark * mark,u32 if_id,u8 type,int dir,struct xfrm_selector * sel,struct xfrm_sec_ctx * ctx,int delete,int * err)1637 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1638 u8 type, int dir, struct xfrm_selector *sel, 1639 struct xfrm_sec_ctx *ctx, int delete, int *err) 1640 { 1641 struct xfrm_pol_inexact_bin *bin = NULL; 1642 struct xfrm_policy *pol, *ret = NULL; 1643 struct hlist_head *chain; 1644 1645 *err = 0; 1646 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1647 chain = policy_hash_bysel(net, sel, sel->family, dir); 1648 if (!chain) { 1649 struct xfrm_pol_inexact_candidates cand; 1650 int i; 1651 1652 bin = xfrm_policy_inexact_lookup(net, type, 1653 sel->family, dir, if_id); 1654 if (!bin) { 1655 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1656 return NULL; 1657 } 1658 1659 if (!xfrm_policy_find_inexact_candidates(&cand, bin, 1660 &sel->saddr, 1661 &sel->daddr)) { 1662 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1663 return NULL; 1664 } 1665 1666 pol = NULL; 1667 for (i = 0; i < ARRAY_SIZE(cand.res); i++) { 1668 struct xfrm_policy *tmp; 1669 1670 tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, 1671 if_id, type, dir, 1672 sel, ctx); 1673 if (!tmp) 1674 continue; 1675 1676 if (!pol || tmp->pos < pol->pos) 1677 pol = tmp; 1678 } 1679 } else { 1680 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, 1681 sel, ctx); 1682 } 1683 1684 if (pol) { 1685 xfrm_pol_hold(pol); 1686 if (delete) { 1687 *err = security_xfrm_policy_delete(pol->security); 1688 if (*err) { 1689 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1690 return pol; 1691 } 1692 __xfrm_policy_unlink(pol, dir); 1693 } 1694 ret = pol; 1695 } 1696 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1697 1698 if (ret && delete) 1699 xfrm_policy_kill(ret); 1700 if (bin && delete) 1701 xfrm_policy_inexact_prune_bin(bin); 1702 return ret; 1703 } 1704 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 1705 1706 struct xfrm_policy * xfrm_policy_byid(struct net * net,const struct xfrm_mark * mark,u32 if_id,u8 type,int dir,u32 id,int delete,int * err)1707 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id, 1708 u8 type, int dir, u32 id, int delete, int *err) 1709 { 1710 struct xfrm_policy *pol, *ret; 1711 struct hlist_head *chain; 1712 1713 *err = -ENOENT; 1714 if (xfrm_policy_id2dir(id) != dir) 1715 return NULL; 1716 1717 *err = 0; 1718 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1719 chain = net->xfrm.policy_byidx + idx_hash(net, id); 1720 ret = NULL; 1721 hlist_for_each_entry(pol, chain, byidx) { 1722 if (pol->type == type && pol->index == id && 1723 pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) { 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 xfrm_policy_flush_secctx_check(struct net * net,u8 type,bool task_valid)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 xfrm_dev_policy_flush_secctx_check(struct net * net,struct net_device * dev,bool task_valid)1768 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, 1769 struct net_device *dev, 1770 bool task_valid) 1771 { 1772 struct xfrm_policy *pol; 1773 int err = 0; 1774 1775 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1776 if (pol->walk.dead || 1777 xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || 1778 pol->xdo.dev != dev) 1779 continue; 1780 1781 err = security_xfrm_policy_delete(pol->security); 1782 if (err) { 1783 xfrm_audit_policy_delete(pol, 0, task_valid); 1784 return err; 1785 } 1786 } 1787 return err; 1788 } 1789 #else 1790 static inline int xfrm_policy_flush_secctx_check(struct net * net,u8 type,bool task_valid)1791 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 1792 { 1793 return 0; 1794 } 1795 xfrm_dev_policy_flush_secctx_check(struct net * net,struct net_device * dev,bool task_valid)1796 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, 1797 struct net_device *dev, 1798 bool task_valid) 1799 { 1800 return 0; 1801 } 1802 #endif 1803 xfrm_policy_flush(struct net * net,u8 type,bool task_valid)1804 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 1805 { 1806 int dir, err = 0, cnt = 0; 1807 struct xfrm_policy *pol; 1808 1809 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1810 1811 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 1812 if (err) 1813 goto out; 1814 1815 again: 1816 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1817 if (pol->walk.dead) 1818 continue; 1819 1820 dir = xfrm_policy_id2dir(pol->index); 1821 if (dir >= XFRM_POLICY_MAX || 1822 pol->type != type) 1823 continue; 1824 1825 __xfrm_policy_unlink(pol, dir); 1826 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1827 cnt++; 1828 xfrm_audit_policy_delete(pol, 1, task_valid); 1829 xfrm_policy_kill(pol); 1830 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1831 goto again; 1832 } 1833 if (cnt) 1834 __xfrm_policy_inexact_flush(net); 1835 else 1836 err = -ESRCH; 1837 out: 1838 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1839 return err; 1840 } 1841 EXPORT_SYMBOL(xfrm_policy_flush); 1842 xfrm_dev_policy_flush(struct net * net,struct net_device * dev,bool task_valid)1843 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev, 1844 bool task_valid) 1845 { 1846 int dir, err = 0, cnt = 0; 1847 struct xfrm_policy *pol; 1848 1849 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1850 1851 err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid); 1852 if (err) 1853 goto out; 1854 1855 again: 1856 list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { 1857 if (pol->walk.dead) 1858 continue; 1859 1860 dir = xfrm_policy_id2dir(pol->index); 1861 if (dir >= XFRM_POLICY_MAX || 1862 pol->xdo.dev != dev) 1863 continue; 1864 1865 __xfrm_policy_unlink(pol, dir); 1866 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1867 cnt++; 1868 xfrm_audit_policy_delete(pol, 1, task_valid); 1869 xfrm_policy_kill(pol); 1870 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1871 goto again; 1872 } 1873 if (cnt) 1874 __xfrm_policy_inexact_flush(net); 1875 else 1876 err = -ESRCH; 1877 out: 1878 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1879 return err; 1880 } 1881 EXPORT_SYMBOL(xfrm_dev_policy_flush); 1882 xfrm_policy_walk(struct net * net,struct xfrm_policy_walk * walk,int (* func)(struct xfrm_policy *,int,int,void *),void * data)1883 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 1884 int (*func)(struct xfrm_policy *, int, int, void*), 1885 void *data) 1886 { 1887 struct xfrm_policy *pol; 1888 struct xfrm_policy_walk_entry *x; 1889 int error = 0; 1890 1891 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1892 walk->type != XFRM_POLICY_TYPE_ANY) 1893 return -EINVAL; 1894 1895 if (list_empty(&walk->walk.all) && walk->seq != 0) 1896 return 0; 1897 1898 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1899 if (list_empty(&walk->walk.all)) 1900 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1901 else 1902 x = list_first_entry(&walk->walk.all, 1903 struct xfrm_policy_walk_entry, all); 1904 1905 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1906 if (x->dead) 1907 continue; 1908 pol = container_of(x, struct xfrm_policy, walk); 1909 if (walk->type != XFRM_POLICY_TYPE_ANY && 1910 walk->type != pol->type) 1911 continue; 1912 error = func(pol, xfrm_policy_id2dir(pol->index), 1913 walk->seq, data); 1914 if (error) { 1915 list_move_tail(&walk->walk.all, &x->all); 1916 goto out; 1917 } 1918 walk->seq++; 1919 } 1920 if (walk->seq == 0) { 1921 error = -ENOENT; 1922 goto out; 1923 } 1924 list_del_init(&walk->walk.all); 1925 out: 1926 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1927 return error; 1928 } 1929 EXPORT_SYMBOL(xfrm_policy_walk); 1930 xfrm_policy_walk_init(struct xfrm_policy_walk * walk,u8 type)1931 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1932 { 1933 INIT_LIST_HEAD(&walk->walk.all); 1934 walk->walk.dead = 1; 1935 walk->type = type; 1936 walk->seq = 0; 1937 } 1938 EXPORT_SYMBOL(xfrm_policy_walk_init); 1939 xfrm_policy_walk_done(struct xfrm_policy_walk * walk,struct net * net)1940 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1941 { 1942 if (list_empty(&walk->walk.all)) 1943 return; 1944 1945 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1946 list_del(&walk->walk.all); 1947 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1948 } 1949 EXPORT_SYMBOL(xfrm_policy_walk_done); 1950 1951 /* 1952 * Find policy to apply to this flow. 1953 * 1954 * Returns 0 if policy found, else an -errno. 1955 */ xfrm_policy_match(const struct xfrm_policy * pol,const struct flowi * fl,u8 type,u16 family,u32 if_id)1956 static int xfrm_policy_match(const struct xfrm_policy *pol, 1957 const struct flowi *fl, 1958 u8 type, u16 family, u32 if_id) 1959 { 1960 const struct xfrm_selector *sel = &pol->selector; 1961 int ret = -ESRCH; 1962 bool match; 1963 1964 if (pol->family != family || 1965 pol->if_id != if_id || 1966 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1967 pol->type != type) 1968 return ret; 1969 1970 match = xfrm_selector_match(sel, fl, family); 1971 if (match) 1972 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid); 1973 return ret; 1974 } 1975 1976 static struct xfrm_pol_inexact_node * xfrm_policy_lookup_inexact_addr(const struct rb_root * r,seqcount_spinlock_t * count,const xfrm_address_t * addr,u16 family)1977 xfrm_policy_lookup_inexact_addr(const struct rb_root *r, 1978 seqcount_spinlock_t *count, 1979 const xfrm_address_t *addr, u16 family) 1980 { 1981 const struct rb_node *parent; 1982 int seq; 1983 1984 again: 1985 seq = read_seqcount_begin(count); 1986 1987 parent = rcu_dereference_raw(r->rb_node); 1988 while (parent) { 1989 struct xfrm_pol_inexact_node *node; 1990 int delta; 1991 1992 node = rb_entry(parent, struct xfrm_pol_inexact_node, node); 1993 1994 delta = xfrm_policy_addr_delta(addr, &node->addr, 1995 node->prefixlen, family); 1996 if (delta < 0) { 1997 parent = rcu_dereference_raw(parent->rb_left); 1998 continue; 1999 } else if (delta > 0) { 2000 parent = rcu_dereference_raw(parent->rb_right); 2001 continue; 2002 } 2003 2004 return node; 2005 } 2006 2007 if (read_seqcount_retry(count, seq)) 2008 goto again; 2009 2010 return NULL; 2011 } 2012 2013 static bool xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates * cand,struct xfrm_pol_inexact_bin * b,const xfrm_address_t * saddr,const xfrm_address_t * daddr)2014 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, 2015 struct xfrm_pol_inexact_bin *b, 2016 const xfrm_address_t *saddr, 2017 const xfrm_address_t *daddr) 2018 { 2019 struct xfrm_pol_inexact_node *n; 2020 u16 family; 2021 2022 if (!b) 2023 return false; 2024 2025 family = b->k.family; 2026 memset(cand, 0, sizeof(*cand)); 2027 cand->res[XFRM_POL_CAND_ANY] = &b->hhead; 2028 2029 n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, 2030 family); 2031 if (n) { 2032 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; 2033 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, 2034 family); 2035 if (n) 2036 cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; 2037 } 2038 2039 n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, 2040 family); 2041 if (n) 2042 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; 2043 2044 return true; 2045 } 2046 2047 static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_lookup_rcu(struct net * net,u8 type,u16 family,u8 dir,u32 if_id)2048 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, 2049 u8 dir, u32 if_id) 2050 { 2051 struct xfrm_pol_inexact_key k = { 2052 .family = family, 2053 .type = type, 2054 .dir = dir, 2055 .if_id = if_id, 2056 }; 2057 2058 write_pnet(&k.net, net); 2059 2060 return rhashtable_lookup(&xfrm_policy_inexact_table, &k, 2061 xfrm_pol_inexact_params); 2062 } 2063 2064 static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_lookup(struct net * net,u8 type,u16 family,u8 dir,u32 if_id)2065 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, 2066 u8 dir, u32 if_id) 2067 { 2068 struct xfrm_pol_inexact_bin *bin; 2069 2070 lockdep_assert_held(&net->xfrm.xfrm_policy_lock); 2071 2072 rcu_read_lock(); 2073 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2074 rcu_read_unlock(); 2075 2076 return bin; 2077 } 2078 2079 static struct xfrm_policy * __xfrm_policy_eval_candidates(struct hlist_head * chain,struct xfrm_policy * prefer,const struct flowi * fl,u8 type,u16 family,u32 if_id)2080 __xfrm_policy_eval_candidates(struct hlist_head *chain, 2081 struct xfrm_policy *prefer, 2082 const struct flowi *fl, 2083 u8 type, u16 family, u32 if_id) 2084 { 2085 u32 priority = prefer ? prefer->priority : ~0u; 2086 struct xfrm_policy *pol; 2087 2088 if (!chain) 2089 return NULL; 2090 2091 hlist_for_each_entry_rcu(pol, chain, bydst) { 2092 int err; 2093 2094 if (pol->priority > priority) 2095 break; 2096 2097 err = xfrm_policy_match(pol, fl, type, family, if_id); 2098 if (err) { 2099 if (err != -ESRCH) 2100 return ERR_PTR(err); 2101 2102 continue; 2103 } 2104 2105 if (prefer) { 2106 /* matches. Is it older than *prefer? */ 2107 if (pol->priority == priority && 2108 prefer->pos < pol->pos) 2109 return prefer; 2110 } 2111 2112 return pol; 2113 } 2114 2115 return NULL; 2116 } 2117 2118 static struct xfrm_policy * xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates * cand,struct xfrm_policy * prefer,const struct flowi * fl,u8 type,u16 family,u32 if_id)2119 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, 2120 struct xfrm_policy *prefer, 2121 const struct flowi *fl, 2122 u8 type, u16 family, u32 if_id) 2123 { 2124 struct xfrm_policy *tmp; 2125 int i; 2126 2127 for (i = 0; i < ARRAY_SIZE(cand->res); i++) { 2128 tmp = __xfrm_policy_eval_candidates(cand->res[i], 2129 prefer, 2130 fl, type, family, if_id); 2131 if (!tmp) 2132 continue; 2133 2134 if (IS_ERR(tmp)) 2135 return tmp; 2136 prefer = tmp; 2137 } 2138 2139 return prefer; 2140 } 2141 xfrm_policy_lookup_bytype(struct net * net,u8 type,const struct flowi * fl,u16 family,u8 dir,u32 if_id)2142 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 2143 const struct flowi *fl, 2144 u16 family, u8 dir, 2145 u32 if_id) 2146 { 2147 struct xfrm_pol_inexact_candidates cand; 2148 const xfrm_address_t *daddr, *saddr; 2149 struct xfrm_pol_inexact_bin *bin; 2150 struct xfrm_policy *pol, *ret; 2151 struct hlist_head *chain; 2152 unsigned int sequence; 2153 int err; 2154 2155 daddr = xfrm_flowi_daddr(fl, family); 2156 saddr = xfrm_flowi_saddr(fl, family); 2157 if (unlikely(!daddr || !saddr)) 2158 return NULL; 2159 2160 rcu_read_lock(); 2161 retry: 2162 do { 2163 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); 2164 chain = policy_hash_direct(net, daddr, saddr, family, dir); 2165 } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)); 2166 2167 ret = NULL; 2168 hlist_for_each_entry_rcu(pol, chain, bydst) { 2169 err = xfrm_policy_match(pol, fl, type, family, if_id); 2170 if (err) { 2171 if (err == -ESRCH) 2172 continue; 2173 else { 2174 ret = ERR_PTR(err); 2175 goto fail; 2176 } 2177 } else { 2178 ret = pol; 2179 break; 2180 } 2181 } 2182 if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET) 2183 goto skip_inexact; 2184 2185 bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); 2186 if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, 2187 daddr)) 2188 goto skip_inexact; 2189 2190 pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, 2191 family, if_id); 2192 if (pol) { 2193 ret = pol; 2194 if (IS_ERR(pol)) 2195 goto fail; 2196 } 2197 2198 skip_inexact: 2199 if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)) 2200 goto retry; 2201 2202 if (ret && !xfrm_pol_hold_rcu(ret)) 2203 goto retry; 2204 fail: 2205 rcu_read_unlock(); 2206 2207 return ret; 2208 } 2209 xfrm_policy_lookup(struct net * net,const struct flowi * fl,u16 family,u8 dir,u32 if_id)2210 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 2211 const struct flowi *fl, 2212 u16 family, u8 dir, u32 if_id) 2213 { 2214 #ifdef CONFIG_XFRM_SUB_POLICY 2215 struct xfrm_policy *pol; 2216 2217 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 2218 dir, if_id); 2219 if (pol != NULL) 2220 return pol; 2221 #endif 2222 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 2223 dir, if_id); 2224 } 2225 xfrm_sk_policy_lookup(const struct sock * sk,int dir,const struct flowi * fl,u16 family,u32 if_id)2226 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 2227 const struct flowi *fl, 2228 u16 family, u32 if_id) 2229 { 2230 struct xfrm_policy *pol; 2231 2232 rcu_read_lock(); 2233 again: 2234 pol = rcu_dereference(sk->sk_policy[dir]); 2235 if (pol != NULL) { 2236 bool match; 2237 int err = 0; 2238 2239 if (pol->family != family) { 2240 pol = NULL; 2241 goto out; 2242 } 2243 2244 match = xfrm_selector_match(&pol->selector, fl, family); 2245 if (match) { 2246 if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v || 2247 pol->if_id != if_id) { 2248 pol = NULL; 2249 goto out; 2250 } 2251 err = security_xfrm_policy_lookup(pol->security, 2252 fl->flowi_secid); 2253 if (!err) { 2254 if (!xfrm_pol_hold_rcu(pol)) 2255 goto again; 2256 } else if (err == -ESRCH) { 2257 pol = NULL; 2258 } else { 2259 pol = ERR_PTR(err); 2260 } 2261 } else 2262 pol = NULL; 2263 } 2264 out: 2265 rcu_read_unlock(); 2266 return pol; 2267 } 2268 xfrm_gen_pos_slow(struct net * net)2269 static u32 xfrm_gen_pos_slow(struct net *net) 2270 { 2271 struct xfrm_policy *policy; 2272 u32 i = 0; 2273 2274 /* oldest entry is last in list */ 2275 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 2276 if (!xfrm_policy_is_dead_or_sk(policy)) 2277 policy->pos = ++i; 2278 } 2279 2280 return i; 2281 } 2282 xfrm_gen_pos(struct net * net)2283 static u32 xfrm_gen_pos(struct net *net) 2284 { 2285 const struct xfrm_policy *policy; 2286 u32 i = 0; 2287 2288 /* most recently added policy is at the head of the list */ 2289 list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) { 2290 if (xfrm_policy_is_dead_or_sk(policy)) 2291 continue; 2292 2293 if (policy->pos == UINT_MAX) 2294 return xfrm_gen_pos_slow(net); 2295 2296 i = policy->pos + 1; 2297 break; 2298 } 2299 2300 return i; 2301 } 2302 __xfrm_policy_link(struct xfrm_policy * pol,int dir)2303 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 2304 { 2305 struct net *net = xp_net(pol); 2306 2307 switch (dir) { 2308 case XFRM_POLICY_IN: 2309 case XFRM_POLICY_FWD: 2310 case XFRM_POLICY_OUT: 2311 pol->pos = xfrm_gen_pos(net); 2312 break; 2313 } 2314 2315 list_add(&pol->walk.all, &net->xfrm.policy_all); 2316 net->xfrm.policy_count[dir]++; 2317 xfrm_pol_hold(pol); 2318 } 2319 __xfrm_policy_unlink(struct xfrm_policy * pol,int dir)2320 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 2321 int dir) 2322 { 2323 struct net *net = xp_net(pol); 2324 2325 if (list_empty(&pol->walk.all)) 2326 return NULL; 2327 2328 /* Socket policies are not hashed. */ 2329 if (!hlist_unhashed(&pol->bydst)) { 2330 hlist_del_rcu(&pol->bydst); 2331 hlist_del(&pol->byidx); 2332 } 2333 2334 list_del_init(&pol->walk.all); 2335 net->xfrm.policy_count[dir]--; 2336 2337 return pol; 2338 } 2339 xfrm_sk_policy_link(struct xfrm_policy * pol,int dir)2340 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 2341 { 2342 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 2343 } 2344 xfrm_sk_policy_unlink(struct xfrm_policy * pol,int dir)2345 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 2346 { 2347 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 2348 } 2349 xfrm_policy_delete(struct xfrm_policy * pol,int dir)2350 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 2351 { 2352 struct net *net = xp_net(pol); 2353 2354 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2355 pol = __xfrm_policy_unlink(pol, dir); 2356 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2357 if (pol) { 2358 xfrm_policy_kill(pol); 2359 return 0; 2360 } 2361 return -ENOENT; 2362 } 2363 EXPORT_SYMBOL(xfrm_policy_delete); 2364 xfrm_sk_policy_insert(struct sock * sk,int dir,struct xfrm_policy * pol)2365 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 2366 { 2367 struct net *net = sock_net(sk); 2368 struct xfrm_policy *old_pol; 2369 2370 #ifdef CONFIG_XFRM_SUB_POLICY 2371 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 2372 return -EINVAL; 2373 #endif 2374 2375 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2376 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 2377 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 2378 if (pol) { 2379 pol->curlft.add_time = ktime_get_real_seconds(); 2380 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 2381 xfrm_sk_policy_link(pol, dir); 2382 } 2383 rcu_assign_pointer(sk->sk_policy[dir], pol); 2384 if (old_pol) { 2385 if (pol) 2386 xfrm_policy_requeue(old_pol, pol); 2387 2388 /* Unlinking succeeds always. This is the only function 2389 * allowed to delete or replace socket policy. 2390 */ 2391 xfrm_sk_policy_unlink(old_pol, dir); 2392 } 2393 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2394 2395 if (old_pol) { 2396 xfrm_policy_kill(old_pol); 2397 } 2398 return 0; 2399 } 2400 clone_policy(const struct xfrm_policy * old,int dir)2401 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 2402 { 2403 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 2404 struct net *net = xp_net(old); 2405 2406 if (newp) { 2407 newp->selector = old->selector; 2408 if (security_xfrm_policy_clone(old->security, 2409 &newp->security)) { 2410 kfree(newp); 2411 return NULL; /* ENOMEM */ 2412 } 2413 newp->lft = old->lft; 2414 newp->curlft = old->curlft; 2415 newp->mark = old->mark; 2416 newp->if_id = old->if_id; 2417 newp->action = old->action; 2418 newp->flags = old->flags; 2419 newp->xfrm_nr = old->xfrm_nr; 2420 newp->index = old->index; 2421 newp->type = old->type; 2422 newp->family = old->family; 2423 memcpy(newp->xfrm_vec, old->xfrm_vec, 2424 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 2425 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 2426 xfrm_sk_policy_link(newp, dir); 2427 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 2428 xfrm_pol_put(newp); 2429 } 2430 return newp; 2431 } 2432 __xfrm_sk_clone_policy(struct sock * sk,const struct sock * osk)2433 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 2434 { 2435 const struct xfrm_policy *p; 2436 struct xfrm_policy *np; 2437 int i, ret = 0; 2438 2439 rcu_read_lock(); 2440 for (i = 0; i < 2; i++) { 2441 p = rcu_dereference(osk->sk_policy[i]); 2442 if (p) { 2443 np = clone_policy(p, i); 2444 if (unlikely(!np)) { 2445 ret = -ENOMEM; 2446 break; 2447 } 2448 rcu_assign_pointer(sk->sk_policy[i], np); 2449 } 2450 } 2451 rcu_read_unlock(); 2452 return ret; 2453 } 2454 2455 static int xfrm_get_saddr(unsigned short family,xfrm_address_t * saddr,const struct xfrm_dst_lookup_params * params)2456 xfrm_get_saddr(unsigned short family, xfrm_address_t *saddr, 2457 const struct xfrm_dst_lookup_params *params) 2458 { 2459 int err; 2460 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2461 2462 if (unlikely(afinfo == NULL)) 2463 return -EINVAL; 2464 err = afinfo->get_saddr(saddr, params); 2465 rcu_read_unlock(); 2466 return err; 2467 } 2468 2469 /* Resolve list of templates for the flow, given policy. */ 2470 2471 static int xfrm_tmpl_resolve_one(struct xfrm_policy * policy,const struct flowi * fl,struct xfrm_state ** xfrm,unsigned short family)2472 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 2473 struct xfrm_state **xfrm, unsigned short family) 2474 { 2475 struct net *net = xp_net(policy); 2476 int nx; 2477 int i, error; 2478 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 2479 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 2480 xfrm_address_t tmp; 2481 2482 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 2483 struct xfrm_state *x; 2484 xfrm_address_t *remote = daddr; 2485 xfrm_address_t *local = saddr; 2486 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 2487 2488 if (tmpl->mode == XFRM_MODE_TUNNEL || 2489 tmpl->mode == XFRM_MODE_BEET) { 2490 remote = &tmpl->id.daddr; 2491 local = &tmpl->saddr; 2492 if (xfrm_addr_any(local, tmpl->encap_family)) { 2493 struct xfrm_dst_lookup_params params; 2494 2495 memset(¶ms, 0, sizeof(params)); 2496 params.net = net; 2497 params.oif = fl->flowi_oif; 2498 params.daddr = remote; 2499 error = xfrm_get_saddr(tmpl->encap_family, &tmp, 2500 ¶ms); 2501 if (error) 2502 goto fail; 2503 local = &tmp; 2504 } 2505 } 2506 2507 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 2508 family, policy->if_id); 2509 if (x && x->dir && x->dir != XFRM_SA_DIR_OUT) { 2510 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEDIRERROR); 2511 xfrm_state_put(x); 2512 error = -EINVAL; 2513 goto fail; 2514 } 2515 2516 if (x && x->km.state == XFRM_STATE_VALID) { 2517 xfrm[nx++] = x; 2518 daddr = remote; 2519 saddr = local; 2520 continue; 2521 } 2522 if (x) { 2523 error = (x->km.state == XFRM_STATE_ERROR ? 2524 -EINVAL : -EAGAIN); 2525 xfrm_state_put(x); 2526 } else if (error == -ESRCH) { 2527 error = -EAGAIN; 2528 } 2529 2530 if (!tmpl->optional) 2531 goto fail; 2532 } 2533 return nx; 2534 2535 fail: 2536 for (nx--; nx >= 0; nx--) 2537 xfrm_state_put(xfrm[nx]); 2538 return error; 2539 } 2540 2541 static int xfrm_tmpl_resolve(struct xfrm_policy ** pols,int npols,const struct flowi * fl,struct xfrm_state ** xfrm,unsigned short family)2542 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 2543 struct xfrm_state **xfrm, unsigned short family) 2544 { 2545 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 2546 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 2547 int cnx = 0; 2548 int error; 2549 int ret; 2550 int i; 2551 2552 for (i = 0; i < npols; i++) { 2553 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 2554 error = -ENOBUFS; 2555 goto fail; 2556 } 2557 2558 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 2559 if (ret < 0) { 2560 error = ret; 2561 goto fail; 2562 } else 2563 cnx += ret; 2564 } 2565 2566 /* found states are sorted for outbound processing */ 2567 if (npols > 1) 2568 xfrm_state_sort(xfrm, tpp, cnx, family); 2569 2570 return cnx; 2571 2572 fail: 2573 for (cnx--; cnx >= 0; cnx--) 2574 xfrm_state_put(tpp[cnx]); 2575 return error; 2576 2577 } 2578 xfrm_get_tos(const struct flowi * fl,int family)2579 static int xfrm_get_tos(const struct flowi *fl, int family) 2580 { 2581 if (family == AF_INET) 2582 return fl->u.ip4.flowi4_tos & INET_DSCP_MASK; 2583 2584 return 0; 2585 } 2586 xfrm_alloc_dst(struct net * net,int family)2587 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 2588 { 2589 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2590 struct dst_ops *dst_ops; 2591 struct xfrm_dst *xdst; 2592 2593 if (!afinfo) 2594 return ERR_PTR(-EINVAL); 2595 2596 switch (family) { 2597 case AF_INET: 2598 dst_ops = &net->xfrm.xfrm4_dst_ops; 2599 break; 2600 #if IS_ENABLED(CONFIG_IPV6) 2601 case AF_INET6: 2602 dst_ops = &net->xfrm.xfrm6_dst_ops; 2603 break; 2604 #endif 2605 default: 2606 BUG(); 2607 } 2608 xdst = dst_alloc(dst_ops, NULL, DST_OBSOLETE_NONE, 0); 2609 2610 if (likely(xdst)) { 2611 memset_after(xdst, 0, u.dst); 2612 } else 2613 xdst = ERR_PTR(-ENOBUFS); 2614 2615 rcu_read_unlock(); 2616 2617 return xdst; 2618 } 2619 xfrm_init_path(struct xfrm_dst * path,struct dst_entry * dst,int nfheader_len)2620 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 2621 int nfheader_len) 2622 { 2623 if (dst->ops->family == AF_INET6) { 2624 path->path_cookie = rt6_get_cookie(dst_rt6_info(dst)); 2625 path->u.rt6.rt6i_nfheader_len = nfheader_len; 2626 } 2627 } 2628 xfrm_fill_dst(struct xfrm_dst * xdst,struct net_device * dev,const struct flowi * fl)2629 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 2630 const struct flowi *fl) 2631 { 2632 const struct xfrm_policy_afinfo *afinfo = 2633 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 2634 int err; 2635 2636 if (!afinfo) 2637 return -EINVAL; 2638 2639 err = afinfo->fill_dst(xdst, dev, fl); 2640 2641 rcu_read_unlock(); 2642 2643 return err; 2644 } 2645 2646 2647 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 2648 * all the metrics... Shortly, bundle a bundle. 2649 */ 2650 xfrm_bundle_create(struct xfrm_policy * policy,struct xfrm_state ** xfrm,struct xfrm_dst ** bundle,int nx,const struct flowi * fl,struct dst_entry * dst)2651 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 2652 struct xfrm_state **xfrm, 2653 struct xfrm_dst **bundle, 2654 int nx, 2655 const struct flowi *fl, 2656 struct dst_entry *dst) 2657 { 2658 const struct xfrm_state_afinfo *afinfo; 2659 const struct xfrm_mode *inner_mode; 2660 struct net *net = xp_net(policy); 2661 unsigned long now = jiffies; 2662 struct net_device *dev; 2663 struct xfrm_dst *xdst_prev = NULL; 2664 struct xfrm_dst *xdst0 = NULL; 2665 int i = 0; 2666 int err; 2667 int header_len = 0; 2668 int nfheader_len = 0; 2669 int trailer_len = 0; 2670 int tos; 2671 int family = policy->selector.family; 2672 xfrm_address_t saddr, daddr; 2673 2674 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 2675 2676 tos = xfrm_get_tos(fl, family); 2677 2678 dst_hold(dst); 2679 2680 for (; i < nx; i++) { 2681 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 2682 struct dst_entry *dst1 = &xdst->u.dst; 2683 2684 err = PTR_ERR(xdst); 2685 if (IS_ERR(xdst)) { 2686 dst_release(dst); 2687 goto put_states; 2688 } 2689 2690 bundle[i] = xdst; 2691 if (!xdst_prev) 2692 xdst0 = xdst; 2693 else 2694 /* Ref count is taken during xfrm_alloc_dst() 2695 * No need to do dst_clone() on dst1 2696 */ 2697 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 2698 2699 if (xfrm[i]->sel.family == AF_UNSPEC) { 2700 inner_mode = xfrm_ip2inner_mode(xfrm[i], 2701 xfrm_af2proto(family)); 2702 if (!inner_mode) { 2703 err = -EAFNOSUPPORT; 2704 dst_release(dst); 2705 goto put_states; 2706 } 2707 } else 2708 inner_mode = &xfrm[i]->inner_mode; 2709 2710 xdst->route = dst; 2711 dst_copy_metrics(dst1, dst); 2712 2713 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 2714 __u32 mark = 0; 2715 int oif; 2716 2717 if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) 2718 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 2719 2720 if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET) 2721 family = xfrm[i]->props.family; 2722 2723 oif = fl->flowi_oif ? : fl->flowi_l3mdev; 2724 dst = xfrm_dst_lookup(xfrm[i], tos, oif, 2725 &saddr, &daddr, family, mark); 2726 err = PTR_ERR(dst); 2727 if (IS_ERR(dst)) 2728 goto put_states; 2729 } else 2730 dst_hold(dst); 2731 2732 dst1->xfrm = xfrm[i]; 2733 xdst->xfrm_genid = xfrm[i]->genid; 2734 2735 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2736 dst1->lastuse = now; 2737 2738 dst1->input = dst_discard; 2739 2740 rcu_read_lock(); 2741 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); 2742 if (likely(afinfo)) 2743 dst1->output = afinfo->output; 2744 else 2745 dst1->output = dst_discard_out; 2746 rcu_read_unlock(); 2747 2748 xdst_prev = xdst; 2749 2750 header_len += xfrm[i]->props.header_len; 2751 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 2752 nfheader_len += xfrm[i]->props.header_len; 2753 trailer_len += xfrm[i]->props.trailer_len; 2754 } 2755 2756 xfrm_dst_set_child(xdst_prev, dst); 2757 xdst0->path = dst; 2758 2759 err = -ENODEV; 2760 dev = dst->dev; 2761 if (!dev) 2762 goto free_dst; 2763 2764 xfrm_init_path(xdst0, dst, nfheader_len); 2765 xfrm_init_pmtu(bundle, nx); 2766 2767 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 2768 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 2769 err = xfrm_fill_dst(xdst_prev, dev, fl); 2770 if (err) 2771 goto free_dst; 2772 2773 xdst_prev->u.dst.header_len = header_len; 2774 xdst_prev->u.dst.trailer_len = trailer_len; 2775 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 2776 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 2777 } 2778 2779 return &xdst0->u.dst; 2780 2781 put_states: 2782 for (; i < nx; i++) 2783 xfrm_state_put(xfrm[i]); 2784 free_dst: 2785 if (xdst0) 2786 dst_release_immediate(&xdst0->u.dst); 2787 2788 return ERR_PTR(err); 2789 } 2790 xfrm_expand_policies(const struct flowi * fl,u16 family,struct xfrm_policy ** pols,int * num_pols,int * num_xfrms)2791 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 2792 struct xfrm_policy **pols, 2793 int *num_pols, int *num_xfrms) 2794 { 2795 int i; 2796 2797 if (*num_pols == 0 || !pols[0]) { 2798 *num_pols = 0; 2799 *num_xfrms = 0; 2800 return 0; 2801 } 2802 if (IS_ERR(pols[0])) { 2803 *num_pols = 0; 2804 return PTR_ERR(pols[0]); 2805 } 2806 2807 *num_xfrms = pols[0]->xfrm_nr; 2808 2809 #ifdef CONFIG_XFRM_SUB_POLICY 2810 if (pols[0]->action == XFRM_POLICY_ALLOW && 2811 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2812 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 2813 XFRM_POLICY_TYPE_MAIN, 2814 fl, family, 2815 XFRM_POLICY_OUT, 2816 pols[0]->if_id); 2817 if (pols[1]) { 2818 if (IS_ERR(pols[1])) { 2819 xfrm_pols_put(pols, *num_pols); 2820 *num_pols = 0; 2821 return PTR_ERR(pols[1]); 2822 } 2823 (*num_pols)++; 2824 (*num_xfrms) += pols[1]->xfrm_nr; 2825 } 2826 } 2827 #endif 2828 for (i = 0; i < *num_pols; i++) { 2829 if (pols[i]->action != XFRM_POLICY_ALLOW) { 2830 *num_xfrms = -1; 2831 break; 2832 } 2833 } 2834 2835 return 0; 2836 2837 } 2838 2839 static struct xfrm_dst * xfrm_resolve_and_create_bundle(struct xfrm_policy ** pols,int num_pols,const struct flowi * fl,u16 family,struct dst_entry * dst_orig)2840 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 2841 const struct flowi *fl, u16 family, 2842 struct dst_entry *dst_orig) 2843 { 2844 struct net *net = xp_net(pols[0]); 2845 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 2846 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2847 struct xfrm_dst *xdst; 2848 struct dst_entry *dst; 2849 int err; 2850 2851 /* Try to instantiate a bundle */ 2852 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 2853 if (err <= 0) { 2854 if (err == 0) 2855 return NULL; 2856 2857 if (err != -EAGAIN) 2858 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2859 return ERR_PTR(err); 2860 } 2861 2862 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 2863 if (IS_ERR(dst)) { 2864 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 2865 return ERR_CAST(dst); 2866 } 2867 2868 xdst = (struct xfrm_dst *)dst; 2869 xdst->num_xfrms = err; 2870 xdst->num_pols = num_pols; 2871 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2872 xdst->policy_genid = atomic_read(&pols[0]->genid); 2873 2874 return xdst; 2875 } 2876 xfrm_policy_queue_process(struct timer_list * t)2877 static void xfrm_policy_queue_process(struct timer_list *t) 2878 { 2879 struct sk_buff *skb; 2880 struct sock *sk; 2881 struct dst_entry *dst; 2882 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 2883 struct net *net = xp_net(pol); 2884 struct xfrm_policy_queue *pq = &pol->polq; 2885 struct flowi fl; 2886 struct sk_buff_head list; 2887 __u32 skb_mark; 2888 2889 spin_lock(&pq->hold_queue.lock); 2890 skb = skb_peek(&pq->hold_queue); 2891 if (!skb) { 2892 spin_unlock(&pq->hold_queue.lock); 2893 goto out; 2894 } 2895 dst = skb_dst(skb); 2896 sk = skb->sk; 2897 2898 /* Fixup the mark to support VTI. */ 2899 skb_mark = skb->mark; 2900 skb->mark = pol->mark.v; 2901 xfrm_decode_session(net, skb, &fl, dst->ops->family); 2902 skb->mark = skb_mark; 2903 spin_unlock(&pq->hold_queue.lock); 2904 2905 dst_hold(xfrm_dst_path(dst)); 2906 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 2907 if (IS_ERR(dst)) 2908 goto purge_queue; 2909 2910 if (dst->flags & DST_XFRM_QUEUE) { 2911 dst_release(dst); 2912 2913 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 2914 goto purge_queue; 2915 2916 pq->timeout = pq->timeout << 1; 2917 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 2918 xfrm_pol_hold(pol); 2919 goto out; 2920 } 2921 2922 dst_release(dst); 2923 2924 __skb_queue_head_init(&list); 2925 2926 spin_lock(&pq->hold_queue.lock); 2927 pq->timeout = 0; 2928 skb_queue_splice_init(&pq->hold_queue, &list); 2929 spin_unlock(&pq->hold_queue.lock); 2930 2931 while (!skb_queue_empty(&list)) { 2932 skb = __skb_dequeue(&list); 2933 2934 /* Fixup the mark to support VTI. */ 2935 skb_mark = skb->mark; 2936 skb->mark = pol->mark.v; 2937 xfrm_decode_session(net, skb, &fl, skb_dst(skb)->ops->family); 2938 skb->mark = skb_mark; 2939 2940 dst_hold(xfrm_dst_path(skb_dst(skb))); 2941 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 2942 if (IS_ERR(dst)) { 2943 kfree_skb(skb); 2944 continue; 2945 } 2946 2947 nf_reset_ct(skb); 2948 skb_dst_drop(skb); 2949 skb_dst_set(skb, dst); 2950 2951 dst_output(net, skb->sk, skb); 2952 } 2953 2954 out: 2955 xfrm_pol_put(pol); 2956 return; 2957 2958 purge_queue: 2959 pq->timeout = 0; 2960 skb_queue_purge(&pq->hold_queue); 2961 xfrm_pol_put(pol); 2962 } 2963 xdst_queue_output(struct net * net,struct sock * sk,struct sk_buff * skb)2964 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 2965 { 2966 unsigned long sched_next; 2967 struct dst_entry *dst = skb_dst(skb); 2968 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 2969 struct xfrm_policy *pol = xdst->pols[0]; 2970 struct xfrm_policy_queue *pq = &pol->polq; 2971 2972 if (unlikely(skb_fclone_busy(sk, skb))) { 2973 kfree_skb(skb); 2974 return 0; 2975 } 2976 2977 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 2978 kfree_skb(skb); 2979 return -EAGAIN; 2980 } 2981 2982 skb_dst_force(skb); 2983 2984 spin_lock_bh(&pq->hold_queue.lock); 2985 2986 if (!pq->timeout) 2987 pq->timeout = XFRM_QUEUE_TMO_MIN; 2988 2989 sched_next = jiffies + pq->timeout; 2990 2991 if (del_timer(&pq->hold_timer)) { 2992 if (time_before(pq->hold_timer.expires, sched_next)) 2993 sched_next = pq->hold_timer.expires; 2994 xfrm_pol_put(pol); 2995 } 2996 2997 __skb_queue_tail(&pq->hold_queue, skb); 2998 if (!mod_timer(&pq->hold_timer, sched_next)) 2999 xfrm_pol_hold(pol); 3000 3001 spin_unlock_bh(&pq->hold_queue.lock); 3002 3003 return 0; 3004 } 3005 xfrm_create_dummy_bundle(struct net * net,struct xfrm_flo * xflo,const struct flowi * fl,int num_xfrms,u16 family)3006 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 3007 struct xfrm_flo *xflo, 3008 const struct flowi *fl, 3009 int num_xfrms, 3010 u16 family) 3011 { 3012 int err; 3013 struct net_device *dev; 3014 struct dst_entry *dst; 3015 struct dst_entry *dst1; 3016 struct xfrm_dst *xdst; 3017 3018 xdst = xfrm_alloc_dst(net, family); 3019 if (IS_ERR(xdst)) 3020 return xdst; 3021 3022 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 3023 net->xfrm.sysctl_larval_drop || 3024 num_xfrms <= 0) 3025 return xdst; 3026 3027 dst = xflo->dst_orig; 3028 dst1 = &xdst->u.dst; 3029 dst_hold(dst); 3030 xdst->route = dst; 3031 3032 dst_copy_metrics(dst1, dst); 3033 3034 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 3035 dst1->flags |= DST_XFRM_QUEUE; 3036 dst1->lastuse = jiffies; 3037 3038 dst1->input = dst_discard; 3039 dst1->output = xdst_queue_output; 3040 3041 dst_hold(dst); 3042 xfrm_dst_set_child(xdst, dst); 3043 xdst->path = dst; 3044 3045 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 3046 3047 err = -ENODEV; 3048 dev = dst->dev; 3049 if (!dev) 3050 goto free_dst; 3051 3052 err = xfrm_fill_dst(xdst, dev, fl); 3053 if (err) 3054 goto free_dst; 3055 3056 out: 3057 return xdst; 3058 3059 free_dst: 3060 dst_release(dst1); 3061 xdst = ERR_PTR(err); 3062 goto out; 3063 } 3064 xfrm_bundle_lookup(struct net * net,const struct flowi * fl,u16 family,u8 dir,struct xfrm_flo * xflo,u32 if_id)3065 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 3066 const struct flowi *fl, 3067 u16 family, u8 dir, 3068 struct xfrm_flo *xflo, u32 if_id) 3069 { 3070 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3071 int num_pols = 0, num_xfrms = 0, err; 3072 struct xfrm_dst *xdst; 3073 3074 /* Resolve policies to use if we couldn't get them from 3075 * previous cache entry */ 3076 num_pols = 1; 3077 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 3078 err = xfrm_expand_policies(fl, family, pols, 3079 &num_pols, &num_xfrms); 3080 if (err < 0) 3081 goto inc_error; 3082 if (num_pols == 0) 3083 return NULL; 3084 if (num_xfrms <= 0) 3085 goto make_dummy_bundle; 3086 3087 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 3088 xflo->dst_orig); 3089 if (IS_ERR(xdst)) { 3090 err = PTR_ERR(xdst); 3091 if (err == -EREMOTE) { 3092 xfrm_pols_put(pols, num_pols); 3093 return NULL; 3094 } 3095 3096 if (err != -EAGAIN) 3097 goto error; 3098 goto make_dummy_bundle; 3099 } else if (xdst == NULL) { 3100 num_xfrms = 0; 3101 goto make_dummy_bundle; 3102 } 3103 3104 return xdst; 3105 3106 make_dummy_bundle: 3107 /* We found policies, but there's no bundles to instantiate: 3108 * either because the policy blocks, has no transformations or 3109 * we could not build template (no xfrm_states).*/ 3110 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 3111 if (IS_ERR(xdst)) { 3112 xfrm_pols_put(pols, num_pols); 3113 return ERR_CAST(xdst); 3114 } 3115 xdst->num_pols = num_pols; 3116 xdst->num_xfrms = num_xfrms; 3117 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 3118 3119 return xdst; 3120 3121 inc_error: 3122 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 3123 error: 3124 xfrm_pols_put(pols, num_pols); 3125 return ERR_PTR(err); 3126 } 3127 make_blackhole(struct net * net,u16 family,struct dst_entry * dst_orig)3128 static struct dst_entry *make_blackhole(struct net *net, u16 family, 3129 struct dst_entry *dst_orig) 3130 { 3131 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 3132 struct dst_entry *ret; 3133 3134 if (!afinfo) { 3135 dst_release(dst_orig); 3136 return ERR_PTR(-EINVAL); 3137 } else { 3138 ret = afinfo->blackhole_route(net, dst_orig); 3139 } 3140 rcu_read_unlock(); 3141 3142 return ret; 3143 } 3144 3145 /* Finds/creates a bundle for given flow and if_id 3146 * 3147 * At the moment we eat a raw IP route. Mostly to speed up lookups 3148 * on interfaces with disabled IPsec. 3149 * 3150 * xfrm_lookup uses an if_id of 0 by default, and is provided for 3151 * compatibility 3152 */ xfrm_lookup_with_ifid(struct net * net,struct dst_entry * dst_orig,const struct flowi * fl,const struct sock * sk,int flags,u32 if_id)3153 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 3154 struct dst_entry *dst_orig, 3155 const struct flowi *fl, 3156 const struct sock *sk, 3157 int flags, u32 if_id) 3158 { 3159 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3160 struct xfrm_dst *xdst; 3161 struct dst_entry *dst, *route; 3162 u16 family = dst_orig->ops->family; 3163 u8 dir = XFRM_POLICY_OUT; 3164 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 3165 3166 dst = NULL; 3167 xdst = NULL; 3168 route = NULL; 3169 3170 sk = sk_const_to_full_sk(sk); 3171 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 3172 num_pols = 1; 3173 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 3174 if_id); 3175 err = xfrm_expand_policies(fl, family, pols, 3176 &num_pols, &num_xfrms); 3177 if (err < 0) 3178 goto dropdst; 3179 3180 if (num_pols) { 3181 if (num_xfrms <= 0) { 3182 drop_pols = num_pols; 3183 goto no_transform; 3184 } 3185 3186 xdst = xfrm_resolve_and_create_bundle( 3187 pols, num_pols, fl, 3188 family, dst_orig); 3189 3190 if (IS_ERR(xdst)) { 3191 xfrm_pols_put(pols, num_pols); 3192 err = PTR_ERR(xdst); 3193 if (err == -EREMOTE) 3194 goto nopol; 3195 3196 goto dropdst; 3197 } else if (xdst == NULL) { 3198 num_xfrms = 0; 3199 drop_pols = num_pols; 3200 goto no_transform; 3201 } 3202 3203 route = xdst->route; 3204 } 3205 } 3206 3207 if (xdst == NULL) { 3208 struct xfrm_flo xflo; 3209 3210 xflo.dst_orig = dst_orig; 3211 xflo.flags = flags; 3212 3213 /* To accelerate a bit... */ 3214 if (!if_id && ((dst_orig->flags & DST_NOXFRM) || 3215 !net->xfrm.policy_count[XFRM_POLICY_OUT])) 3216 goto nopol; 3217 3218 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 3219 if (xdst == NULL) 3220 goto nopol; 3221 if (IS_ERR(xdst)) { 3222 err = PTR_ERR(xdst); 3223 goto dropdst; 3224 } 3225 3226 num_pols = xdst->num_pols; 3227 num_xfrms = xdst->num_xfrms; 3228 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 3229 route = xdst->route; 3230 } 3231 3232 dst = &xdst->u.dst; 3233 if (route == NULL && num_xfrms > 0) { 3234 /* The only case when xfrm_bundle_lookup() returns a 3235 * bundle with null route, is when the template could 3236 * not be resolved. It means policies are there, but 3237 * bundle could not be created, since we don't yet 3238 * have the xfrm_state's. We need to wait for KM to 3239 * negotiate new SA's or bail out with error.*/ 3240 if (net->xfrm.sysctl_larval_drop) { 3241 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3242 err = -EREMOTE; 3243 goto error; 3244 } 3245 3246 err = -EAGAIN; 3247 3248 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 3249 goto error; 3250 } 3251 3252 no_transform: 3253 if (num_pols == 0) 3254 goto nopol; 3255 3256 if ((flags & XFRM_LOOKUP_ICMP) && 3257 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 3258 err = -ENOENT; 3259 goto error; 3260 } 3261 3262 for (i = 0; i < num_pols; i++) 3263 WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds()); 3264 3265 if (num_xfrms < 0) { 3266 /* Prohibit the flow */ 3267 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 3268 err = -EPERM; 3269 goto error; 3270 } else if (num_xfrms > 0) { 3271 /* Flow transformed */ 3272 dst_release(dst_orig); 3273 } else { 3274 /* Flow passes untransformed */ 3275 dst_release(dst); 3276 dst = dst_orig; 3277 } 3278 ok: 3279 xfrm_pols_put(pols, drop_pols); 3280 if (dst && dst->xfrm && 3281 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 3282 dst->flags |= DST_XFRM_TUNNEL; 3283 return dst; 3284 3285 nopol: 3286 if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) && 3287 net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { 3288 err = -EPERM; 3289 goto error; 3290 } 3291 if (!(flags & XFRM_LOOKUP_ICMP)) { 3292 dst = dst_orig; 3293 goto ok; 3294 } 3295 err = -ENOENT; 3296 error: 3297 dst_release(dst); 3298 dropdst: 3299 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 3300 dst_release(dst_orig); 3301 xfrm_pols_put(pols, drop_pols); 3302 return ERR_PTR(err); 3303 } 3304 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 3305 3306 /* Main function: finds/creates a bundle for given flow. 3307 * 3308 * At the moment we eat a raw IP route. Mostly to speed up lookups 3309 * on interfaces with disabled IPsec. 3310 */ xfrm_lookup(struct net * net,struct dst_entry * dst_orig,const struct flowi * fl,const struct sock * sk,int flags)3311 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 3312 const struct flowi *fl, const struct sock *sk, 3313 int flags) 3314 { 3315 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 3316 } 3317 EXPORT_SYMBOL(xfrm_lookup); 3318 3319 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 3320 * Otherwise we may send out blackholed packets. 3321 */ xfrm_lookup_route(struct net * net,struct dst_entry * dst_orig,const struct flowi * fl,const struct sock * sk,int flags)3322 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 3323 const struct flowi *fl, 3324 const struct sock *sk, int flags) 3325 { 3326 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 3327 flags | XFRM_LOOKUP_QUEUE | 3328 XFRM_LOOKUP_KEEP_DST_REF); 3329 3330 if (PTR_ERR(dst) == -EREMOTE) 3331 return make_blackhole(net, dst_orig->ops->family, dst_orig); 3332 3333 if (IS_ERR(dst)) 3334 dst_release(dst_orig); 3335 3336 return dst; 3337 } 3338 EXPORT_SYMBOL(xfrm_lookup_route); 3339 3340 static inline int xfrm_secpath_reject(int idx,struct sk_buff * skb,const struct flowi * fl)3341 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 3342 { 3343 struct sec_path *sp = skb_sec_path(skb); 3344 struct xfrm_state *x; 3345 3346 if (!sp || idx < 0 || idx >= sp->len) 3347 return 0; 3348 x = sp->xvec[idx]; 3349 if (!x->type->reject) 3350 return 0; 3351 return x->type->reject(x, skb, fl); 3352 } 3353 3354 /* When skb is transformed back to its "native" form, we have to 3355 * check policy restrictions. At the moment we make this in maximally 3356 * stupid way. Shame on me. :-) Of course, connected sockets must 3357 * have policy cached at them. 3358 */ 3359 3360 static inline int xfrm_state_ok(const struct xfrm_tmpl * tmpl,const struct xfrm_state * x,unsigned short family,u32 if_id)3361 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 3362 unsigned short family, u32 if_id) 3363 { 3364 if (xfrm_state_kern(x)) 3365 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 3366 return x->id.proto == tmpl->id.proto && 3367 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 3368 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 3369 x->props.mode == tmpl->mode && 3370 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 3371 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 3372 !(x->props.mode != XFRM_MODE_TRANSPORT && 3373 xfrm_state_addr_cmp(tmpl, x, family)) && 3374 (if_id == 0 || if_id == x->if_id); 3375 } 3376 3377 /* 3378 * 0 or more than 0 is returned when validation is succeeded (either bypass 3379 * because of optional transport mode, or next index of the matched secpath 3380 * state with the template. 3381 * -1 is returned when no matching template is found. 3382 * Otherwise "-2 - errored_index" is returned. 3383 */ 3384 static inline int xfrm_policy_ok(const struct xfrm_tmpl * tmpl,const struct sec_path * sp,int start,unsigned short family,u32 if_id)3385 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 3386 unsigned short family, u32 if_id) 3387 { 3388 int idx = start; 3389 3390 if (tmpl->optional) { 3391 if (tmpl->mode == XFRM_MODE_TRANSPORT) 3392 return start; 3393 } else 3394 start = -1; 3395 for (; idx < sp->len; idx++) { 3396 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id)) 3397 return ++idx; 3398 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 3399 if (idx < sp->verified_cnt) { 3400 /* Secpath entry previously verified, consider optional and 3401 * continue searching 3402 */ 3403 continue; 3404 } 3405 3406 if (start == -1) 3407 start = -2-idx; 3408 break; 3409 } 3410 } 3411 return start; 3412 } 3413 3414 static void decode_session4(const struct xfrm_flow_keys * flkeys,struct flowi * fl,bool reverse)3415 decode_session4(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse) 3416 { 3417 struct flowi4 *fl4 = &fl->u.ip4; 3418 3419 memset(fl4, 0, sizeof(struct flowi4)); 3420 3421 if (reverse) { 3422 fl4->saddr = flkeys->addrs.ipv4.dst; 3423 fl4->daddr = flkeys->addrs.ipv4.src; 3424 fl4->fl4_sport = flkeys->ports.dst; 3425 fl4->fl4_dport = flkeys->ports.src; 3426 } else { 3427 fl4->saddr = flkeys->addrs.ipv4.src; 3428 fl4->daddr = flkeys->addrs.ipv4.dst; 3429 fl4->fl4_sport = flkeys->ports.src; 3430 fl4->fl4_dport = flkeys->ports.dst; 3431 } 3432 3433 switch (flkeys->basic.ip_proto) { 3434 case IPPROTO_GRE: 3435 fl4->fl4_gre_key = flkeys->gre.keyid; 3436 break; 3437 case IPPROTO_ICMP: 3438 fl4->fl4_icmp_type = flkeys->icmp.type; 3439 fl4->fl4_icmp_code = flkeys->icmp.code; 3440 break; 3441 } 3442 3443 fl4->flowi4_proto = flkeys->basic.ip_proto; 3444 fl4->flowi4_tos = flkeys->ip.tos & ~INET_ECN_MASK; 3445 } 3446 3447 #if IS_ENABLED(CONFIG_IPV6) 3448 static void decode_session6(const struct xfrm_flow_keys * flkeys,struct flowi * fl,bool reverse)3449 decode_session6(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse) 3450 { 3451 struct flowi6 *fl6 = &fl->u.ip6; 3452 3453 memset(fl6, 0, sizeof(struct flowi6)); 3454 3455 if (reverse) { 3456 fl6->saddr = flkeys->addrs.ipv6.dst; 3457 fl6->daddr = flkeys->addrs.ipv6.src; 3458 fl6->fl6_sport = flkeys->ports.dst; 3459 fl6->fl6_dport = flkeys->ports.src; 3460 } else { 3461 fl6->saddr = flkeys->addrs.ipv6.src; 3462 fl6->daddr = flkeys->addrs.ipv6.dst; 3463 fl6->fl6_sport = flkeys->ports.src; 3464 fl6->fl6_dport = flkeys->ports.dst; 3465 } 3466 3467 switch (flkeys->basic.ip_proto) { 3468 case IPPROTO_GRE: 3469 fl6->fl6_gre_key = flkeys->gre.keyid; 3470 break; 3471 case IPPROTO_ICMPV6: 3472 fl6->fl6_icmp_type = flkeys->icmp.type; 3473 fl6->fl6_icmp_code = flkeys->icmp.code; 3474 break; 3475 } 3476 3477 fl6->flowi6_proto = flkeys->basic.ip_proto; 3478 } 3479 #endif 3480 __xfrm_decode_session(struct net * net,struct sk_buff * skb,struct flowi * fl,unsigned int family,int reverse)3481 int __xfrm_decode_session(struct net *net, struct sk_buff *skb, struct flowi *fl, 3482 unsigned int family, int reverse) 3483 { 3484 struct xfrm_flow_keys flkeys; 3485 3486 memset(&flkeys, 0, sizeof(flkeys)); 3487 __skb_flow_dissect(net, skb, &xfrm_session_dissector, &flkeys, 3488 NULL, 0, 0, 0, FLOW_DISSECTOR_F_STOP_AT_ENCAP); 3489 3490 switch (family) { 3491 case AF_INET: 3492 decode_session4(&flkeys, fl, reverse); 3493 break; 3494 #if IS_ENABLED(CONFIG_IPV6) 3495 case AF_INET6: 3496 decode_session6(&flkeys, fl, reverse); 3497 break; 3498 #endif 3499 default: 3500 return -EAFNOSUPPORT; 3501 } 3502 3503 fl->flowi_mark = skb->mark; 3504 if (reverse) { 3505 fl->flowi_oif = skb->skb_iif; 3506 } else { 3507 int oif = 0; 3508 3509 if (skb_dst(skb) && skb_dst(skb)->dev) 3510 oif = skb_dst(skb)->dev->ifindex; 3511 3512 fl->flowi_oif = oif; 3513 } 3514 3515 return security_xfrm_decode_session(skb, &fl->flowi_secid); 3516 } 3517 EXPORT_SYMBOL(__xfrm_decode_session); 3518 secpath_has_nontransport(const struct sec_path * sp,int k,int * idxp)3519 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 3520 { 3521 for (; k < sp->len; k++) { 3522 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 3523 *idxp = k; 3524 return 1; 3525 } 3526 } 3527 3528 return 0; 3529 } 3530 icmp_err_packet(const struct flowi * fl,unsigned short family)3531 static bool icmp_err_packet(const struct flowi *fl, unsigned short family) 3532 { 3533 const struct flowi4 *fl4 = &fl->u.ip4; 3534 3535 if (family == AF_INET && 3536 fl4->flowi4_proto == IPPROTO_ICMP && 3537 (fl4->fl4_icmp_type == ICMP_DEST_UNREACH || 3538 fl4->fl4_icmp_type == ICMP_TIME_EXCEEDED)) 3539 return true; 3540 3541 #if IS_ENABLED(CONFIG_IPV6) 3542 if (family == AF_INET6) { 3543 const struct flowi6 *fl6 = &fl->u.ip6; 3544 3545 if (fl6->flowi6_proto == IPPROTO_ICMPV6 && 3546 (fl6->fl6_icmp_type == ICMPV6_DEST_UNREACH || 3547 fl6->fl6_icmp_type == ICMPV6_PKT_TOOBIG || 3548 fl6->fl6_icmp_type == ICMPV6_TIME_EXCEED)) 3549 return true; 3550 } 3551 #endif 3552 return false; 3553 } 3554 xfrm_icmp_flow_decode(struct sk_buff * skb,unsigned short family,const struct flowi * fl,struct flowi * fl1)3555 static bool xfrm_icmp_flow_decode(struct sk_buff *skb, unsigned short family, 3556 const struct flowi *fl, struct flowi *fl1) 3557 { 3558 bool ret = true; 3559 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); 3560 int hl = family == AF_INET ? (sizeof(struct iphdr) + sizeof(struct icmphdr)) : 3561 (sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr)); 3562 3563 if (!newskb) 3564 return true; 3565 3566 if (!pskb_pull(newskb, hl)) 3567 goto out; 3568 3569 skb_reset_network_header(newskb); 3570 3571 if (xfrm_decode_session_reverse(dev_net(skb->dev), newskb, fl1, family) < 0) 3572 goto out; 3573 3574 fl1->flowi_oif = fl->flowi_oif; 3575 fl1->flowi_mark = fl->flowi_mark; 3576 fl1->flowi_tos = fl->flowi_tos; 3577 nf_nat_decode_session(newskb, fl1, family); 3578 ret = false; 3579 3580 out: 3581 consume_skb(newskb); 3582 return ret; 3583 } 3584 xfrm_selector_inner_icmp_match(struct sk_buff * skb,unsigned short family,const struct xfrm_selector * sel,const struct flowi * fl)3585 static bool xfrm_selector_inner_icmp_match(struct sk_buff *skb, unsigned short family, 3586 const struct xfrm_selector *sel, 3587 const struct flowi *fl) 3588 { 3589 bool ret = false; 3590 3591 if (icmp_err_packet(fl, family)) { 3592 struct flowi fl1; 3593 3594 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1)) 3595 return ret; 3596 3597 ret = xfrm_selector_match(sel, &fl1, family); 3598 } 3599 3600 return ret; 3601 } 3602 3603 static inline struct xfrm_in_fwd_icmp(struct sk_buff * skb,const struct flowi * fl,unsigned short family,u32 if_id)3604 xfrm_policy *xfrm_in_fwd_icmp(struct sk_buff *skb, 3605 const struct flowi *fl, unsigned short family, 3606 u32 if_id) 3607 { 3608 struct xfrm_policy *pol = NULL; 3609 3610 if (icmp_err_packet(fl, family)) { 3611 struct flowi fl1; 3612 struct net *net = dev_net(skb->dev); 3613 3614 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1)) 3615 return pol; 3616 3617 pol = xfrm_policy_lookup(net, &fl1, family, XFRM_POLICY_FWD, if_id); 3618 if (IS_ERR(pol)) 3619 pol = NULL; 3620 } 3621 3622 return pol; 3623 } 3624 3625 static inline struct xfrm_out_fwd_icmp(struct sk_buff * skb,struct flowi * fl,unsigned short family,struct dst_entry * dst)3626 dst_entry *xfrm_out_fwd_icmp(struct sk_buff *skb, struct flowi *fl, 3627 unsigned short family, struct dst_entry *dst) 3628 { 3629 if (icmp_err_packet(fl, family)) { 3630 struct net *net = dev_net(skb->dev); 3631 struct dst_entry *dst2; 3632 struct flowi fl1; 3633 3634 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1)) 3635 return dst; 3636 3637 dst_hold(dst); 3638 3639 dst2 = xfrm_lookup(net, dst, &fl1, NULL, (XFRM_LOOKUP_QUEUE | XFRM_LOOKUP_ICMP)); 3640 3641 if (IS_ERR(dst2)) 3642 return dst; 3643 3644 if (dst2->xfrm) { 3645 dst_release(dst); 3646 dst = dst2; 3647 } else { 3648 dst_release(dst2); 3649 } 3650 } 3651 3652 return dst; 3653 } 3654 __xfrm_policy_check(struct sock * sk,int dir,struct sk_buff * skb,unsigned short family)3655 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 3656 unsigned short family) 3657 { 3658 struct net *net = dev_net(skb->dev); 3659 struct xfrm_policy *pol; 3660 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 3661 int npols = 0; 3662 int xfrm_nr; 3663 int pi; 3664 int reverse; 3665 struct flowi fl; 3666 int xerr_idx = -1; 3667 const struct xfrm_if_cb *ifcb; 3668 struct sec_path *sp; 3669 u32 if_id = 0; 3670 3671 rcu_read_lock(); 3672 ifcb = xfrm_if_get_cb(); 3673 3674 if (ifcb) { 3675 struct xfrm_if_decode_session_result r; 3676 3677 if (ifcb->decode_session(skb, family, &r)) { 3678 if_id = r.if_id; 3679 net = r.net; 3680 } 3681 } 3682 rcu_read_unlock(); 3683 3684 reverse = dir & ~XFRM_POLICY_MASK; 3685 dir &= XFRM_POLICY_MASK; 3686 3687 if (__xfrm_decode_session(net, skb, &fl, family, reverse) < 0) { 3688 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 3689 return 0; 3690 } 3691 3692 nf_nat_decode_session(skb, &fl, family); 3693 3694 /* First, check used SA against their selectors. */ 3695 sp = skb_sec_path(skb); 3696 if (sp) { 3697 int i; 3698 3699 for (i = sp->len - 1; i >= 0; i--) { 3700 struct xfrm_state *x = sp->xvec[i]; 3701 int ret = 0; 3702 3703 if (!xfrm_selector_match(&x->sel, &fl, family)) { 3704 ret = 1; 3705 if (x->props.flags & XFRM_STATE_ICMP && 3706 xfrm_selector_inner_icmp_match(skb, family, &x->sel, &fl)) 3707 ret = 0; 3708 if (ret) { 3709 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 3710 return 0; 3711 } 3712 } 3713 } 3714 } 3715 3716 pol = NULL; 3717 sk = sk_to_full_sk(sk); 3718 if (sk && sk->sk_policy[dir]) { 3719 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 3720 if (IS_ERR(pol)) { 3721 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3722 return 0; 3723 } 3724 } 3725 3726 if (!pol) 3727 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 3728 3729 if (IS_ERR(pol)) { 3730 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3731 return 0; 3732 } 3733 3734 if (!pol && dir == XFRM_POLICY_FWD) 3735 pol = xfrm_in_fwd_icmp(skb, &fl, family, if_id); 3736 3737 if (!pol) { 3738 const bool is_crypto_offload = sp && 3739 (xfrm_input_state(skb)->xso.type == XFRM_DEV_OFFLOAD_CRYPTO); 3740 3741 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { 3742 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3743 return 0; 3744 } 3745 3746 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx) && !is_crypto_offload) { 3747 xfrm_secpath_reject(xerr_idx, skb, &fl); 3748 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 3749 return 0; 3750 } 3751 return 1; 3752 } 3753 3754 /* This lockless write can happen from different cpus. */ 3755 WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds()); 3756 3757 pols[0] = pol; 3758 npols++; 3759 #ifdef CONFIG_XFRM_SUB_POLICY 3760 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 3761 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 3762 &fl, family, 3763 XFRM_POLICY_IN, if_id); 3764 if (pols[1]) { 3765 if (IS_ERR(pols[1])) { 3766 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 3767 xfrm_pol_put(pols[0]); 3768 return 0; 3769 } 3770 /* This write can happen from different cpus. */ 3771 WRITE_ONCE(pols[1]->curlft.use_time, 3772 ktime_get_real_seconds()); 3773 npols++; 3774 } 3775 } 3776 #endif 3777 3778 if (pol->action == XFRM_POLICY_ALLOW) { 3779 static struct sec_path dummy; 3780 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 3781 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 3782 struct xfrm_tmpl **tpp = tp; 3783 int ti = 0; 3784 int i, k; 3785 3786 sp = skb_sec_path(skb); 3787 if (!sp) 3788 sp = &dummy; 3789 3790 for (pi = 0; pi < npols; pi++) { 3791 if (pols[pi] != pol && 3792 pols[pi]->action != XFRM_POLICY_ALLOW) { 3793 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3794 goto reject; 3795 } 3796 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 3797 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 3798 goto reject_error; 3799 } 3800 for (i = 0; i < pols[pi]->xfrm_nr; i++) 3801 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 3802 } 3803 xfrm_nr = ti; 3804 3805 if (npols > 1) { 3806 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 3807 tpp = stp; 3808 } 3809 3810 /* For each tunnel xfrm, find the first matching tmpl. 3811 * For each tmpl before that, find corresponding xfrm. 3812 * Order is _important_. Later we will implement 3813 * some barriers, but at the moment barriers 3814 * are implied between each two transformations. 3815 * Upon success, marks secpath entries as having been 3816 * verified to allow them to be skipped in future policy 3817 * checks (e.g. nested tunnels). 3818 */ 3819 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 3820 k = xfrm_policy_ok(tpp[i], sp, k, family, if_id); 3821 if (k < 0) { 3822 if (k < -1) 3823 /* "-2 - errored_index" returned */ 3824 xerr_idx = -(2+k); 3825 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3826 goto reject; 3827 } 3828 } 3829 3830 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 3831 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 3832 goto reject; 3833 } 3834 3835 xfrm_pols_put(pols, npols); 3836 sp->verified_cnt = k; 3837 3838 return 1; 3839 } 3840 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 3841 3842 reject: 3843 xfrm_secpath_reject(xerr_idx, skb, &fl); 3844 reject_error: 3845 xfrm_pols_put(pols, npols); 3846 return 0; 3847 } 3848 EXPORT_SYMBOL(__xfrm_policy_check); 3849 __xfrm_route_forward(struct sk_buff * skb,unsigned short family)3850 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 3851 { 3852 struct net *net = dev_net(skb->dev); 3853 struct flowi fl; 3854 struct dst_entry *dst; 3855 int res = 1; 3856 3857 if (xfrm_decode_session(net, skb, &fl, family) < 0) { 3858 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3859 return 0; 3860 } 3861 3862 skb_dst_force(skb); 3863 if (!skb_dst(skb)) { 3864 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 3865 return 0; 3866 } 3867 3868 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 3869 if (IS_ERR(dst)) { 3870 res = 0; 3871 dst = NULL; 3872 } 3873 3874 if (dst && !dst->xfrm) 3875 dst = xfrm_out_fwd_icmp(skb, &fl, family, dst); 3876 3877 skb_dst_set(skb, dst); 3878 return res; 3879 } 3880 EXPORT_SYMBOL(__xfrm_route_forward); 3881 3882 /* Optimize later using cookies and generation ids. */ 3883 xfrm_dst_check(struct dst_entry * dst,u32 cookie)3884 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 3885 { 3886 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 3887 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 3888 * get validated by dst_ops->check on every use. We do this 3889 * because when a normal route referenced by an XFRM dst is 3890 * obsoleted we do not go looking around for all parent 3891 * referencing XFRM dsts so that we can invalidate them. It 3892 * is just too much work. Instead we make the checks here on 3893 * every use. For example: 3894 * 3895 * XFRM dst A --> IPv4 dst X 3896 * 3897 * X is the "xdst->route" of A (X is also the "dst->path" of A 3898 * in this example). If X is marked obsolete, "A" will not 3899 * notice. That's what we are validating here via the 3900 * stale_bundle() check. 3901 * 3902 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 3903 * be marked on it. 3904 * This will force stale_bundle() to fail on any xdst bundle with 3905 * this dst linked in it. 3906 */ 3907 if (dst->obsolete < 0 && !stale_bundle(dst)) 3908 return dst; 3909 3910 return NULL; 3911 } 3912 stale_bundle(struct dst_entry * dst)3913 static int stale_bundle(struct dst_entry *dst) 3914 { 3915 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 3916 } 3917 xfrm_dst_ifdown(struct dst_entry * dst,struct net_device * dev)3918 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 3919 { 3920 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 3921 dst->dev = blackhole_netdev; 3922 dev_hold(dst->dev); 3923 dev_put(dev); 3924 } 3925 } 3926 EXPORT_SYMBOL(xfrm_dst_ifdown); 3927 xfrm_link_failure(struct sk_buff * skb)3928 static void xfrm_link_failure(struct sk_buff *skb) 3929 { 3930 /* Impossible. Such dst must be popped before reaches point of failure. */ 3931 } 3932 xfrm_negative_advice(struct sock * sk,struct dst_entry * dst)3933 static void xfrm_negative_advice(struct sock *sk, struct dst_entry *dst) 3934 { 3935 if (dst->obsolete) 3936 sk_dst_reset(sk); 3937 } 3938 xfrm_init_pmtu(struct xfrm_dst ** bundle,int nr)3939 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 3940 { 3941 while (nr--) { 3942 struct xfrm_dst *xdst = bundle[nr]; 3943 u32 pmtu, route_mtu_cached; 3944 struct dst_entry *dst; 3945 3946 dst = &xdst->u.dst; 3947 pmtu = dst_mtu(xfrm_dst_child(dst)); 3948 xdst->child_mtu_cached = pmtu; 3949 3950 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 3951 3952 route_mtu_cached = dst_mtu(xdst->route); 3953 xdst->route_mtu_cached = route_mtu_cached; 3954 3955 if (pmtu > route_mtu_cached) 3956 pmtu = route_mtu_cached; 3957 3958 dst_metric_set(dst, RTAX_MTU, pmtu); 3959 } 3960 } 3961 3962 /* Check that the bundle accepts the flow and its components are 3963 * still valid. 3964 */ 3965 xfrm_bundle_ok(struct xfrm_dst * first)3966 static int xfrm_bundle_ok(struct xfrm_dst *first) 3967 { 3968 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 3969 struct dst_entry *dst = &first->u.dst; 3970 struct xfrm_dst *xdst; 3971 int start_from, nr; 3972 u32 mtu; 3973 3974 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 3975 (dst->dev && !netif_running(dst->dev))) 3976 return 0; 3977 3978 if (dst->flags & DST_XFRM_QUEUE) 3979 return 1; 3980 3981 start_from = nr = 0; 3982 do { 3983 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 3984 3985 if (dst->xfrm->km.state != XFRM_STATE_VALID) 3986 return 0; 3987 if (xdst->xfrm_genid != dst->xfrm->genid) 3988 return 0; 3989 if (xdst->num_pols > 0 && 3990 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 3991 return 0; 3992 3993 bundle[nr++] = xdst; 3994 3995 mtu = dst_mtu(xfrm_dst_child(dst)); 3996 if (xdst->child_mtu_cached != mtu) { 3997 start_from = nr; 3998 xdst->child_mtu_cached = mtu; 3999 } 4000 4001 if (!dst_check(xdst->route, xdst->route_cookie)) 4002 return 0; 4003 mtu = dst_mtu(xdst->route); 4004 if (xdst->route_mtu_cached != mtu) { 4005 start_from = nr; 4006 xdst->route_mtu_cached = mtu; 4007 } 4008 4009 dst = xfrm_dst_child(dst); 4010 } while (dst->xfrm); 4011 4012 if (likely(!start_from)) 4013 return 1; 4014 4015 xdst = bundle[start_from - 1]; 4016 mtu = xdst->child_mtu_cached; 4017 while (start_from--) { 4018 dst = &xdst->u.dst; 4019 4020 mtu = xfrm_state_mtu(dst->xfrm, mtu); 4021 if (mtu > xdst->route_mtu_cached) 4022 mtu = xdst->route_mtu_cached; 4023 dst_metric_set(dst, RTAX_MTU, mtu); 4024 if (!start_from) 4025 break; 4026 4027 xdst = bundle[start_from - 1]; 4028 xdst->child_mtu_cached = mtu; 4029 } 4030 4031 return 1; 4032 } 4033 xfrm_default_advmss(const struct dst_entry * dst)4034 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 4035 { 4036 return dst_metric_advmss(xfrm_dst_path(dst)); 4037 } 4038 xfrm_mtu(const struct dst_entry * dst)4039 static unsigned int xfrm_mtu(const struct dst_entry *dst) 4040 { 4041 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 4042 4043 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 4044 } 4045 xfrm_get_dst_nexthop(const struct dst_entry * dst,const void * daddr)4046 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 4047 const void *daddr) 4048 { 4049 while (dst->xfrm) { 4050 const struct xfrm_state *xfrm = dst->xfrm; 4051 4052 dst = xfrm_dst_child(dst); 4053 4054 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 4055 continue; 4056 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 4057 daddr = xfrm->coaddr; 4058 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 4059 daddr = &xfrm->id.daddr; 4060 } 4061 return daddr; 4062 } 4063 xfrm_neigh_lookup(const struct dst_entry * dst,struct sk_buff * skb,const void * daddr)4064 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 4065 struct sk_buff *skb, 4066 const void *daddr) 4067 { 4068 const struct dst_entry *path = xfrm_dst_path(dst); 4069 4070 if (!skb) 4071 daddr = xfrm_get_dst_nexthop(dst, daddr); 4072 return path->ops->neigh_lookup(path, skb, daddr); 4073 } 4074 xfrm_confirm_neigh(const struct dst_entry * dst,const void * daddr)4075 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 4076 { 4077 const struct dst_entry *path = xfrm_dst_path(dst); 4078 4079 daddr = xfrm_get_dst_nexthop(dst, daddr); 4080 path->ops->confirm_neigh(path, daddr); 4081 } 4082 xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo * afinfo,int family)4083 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 4084 { 4085 int err = 0; 4086 4087 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 4088 return -EAFNOSUPPORT; 4089 4090 spin_lock(&xfrm_policy_afinfo_lock); 4091 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 4092 err = -EEXIST; 4093 else { 4094 struct dst_ops *dst_ops = afinfo->dst_ops; 4095 if (likely(dst_ops->kmem_cachep == NULL)) 4096 dst_ops->kmem_cachep = xfrm_dst_cache; 4097 if (likely(dst_ops->check == NULL)) 4098 dst_ops->check = xfrm_dst_check; 4099 if (likely(dst_ops->default_advmss == NULL)) 4100 dst_ops->default_advmss = xfrm_default_advmss; 4101 if (likely(dst_ops->mtu == NULL)) 4102 dst_ops->mtu = xfrm_mtu; 4103 if (likely(dst_ops->negative_advice == NULL)) 4104 dst_ops->negative_advice = xfrm_negative_advice; 4105 if (likely(dst_ops->link_failure == NULL)) 4106 dst_ops->link_failure = xfrm_link_failure; 4107 if (likely(dst_ops->neigh_lookup == NULL)) 4108 dst_ops->neigh_lookup = xfrm_neigh_lookup; 4109 if (likely(!dst_ops->confirm_neigh)) 4110 dst_ops->confirm_neigh = xfrm_confirm_neigh; 4111 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 4112 } 4113 spin_unlock(&xfrm_policy_afinfo_lock); 4114 4115 return err; 4116 } 4117 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 4118 xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo * afinfo)4119 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 4120 { 4121 struct dst_ops *dst_ops = afinfo->dst_ops; 4122 int i; 4123 4124 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 4125 if (xfrm_policy_afinfo[i] != afinfo) 4126 continue; 4127 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 4128 break; 4129 } 4130 4131 synchronize_rcu(); 4132 4133 dst_ops->kmem_cachep = NULL; 4134 dst_ops->check = NULL; 4135 dst_ops->negative_advice = NULL; 4136 dst_ops->link_failure = NULL; 4137 } 4138 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 4139 xfrm_if_register_cb(const struct xfrm_if_cb * ifcb)4140 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 4141 { 4142 spin_lock(&xfrm_if_cb_lock); 4143 rcu_assign_pointer(xfrm_if_cb, ifcb); 4144 spin_unlock(&xfrm_if_cb_lock); 4145 } 4146 EXPORT_SYMBOL(xfrm_if_register_cb); 4147 xfrm_if_unregister_cb(void)4148 void xfrm_if_unregister_cb(void) 4149 { 4150 RCU_INIT_POINTER(xfrm_if_cb, NULL); 4151 synchronize_rcu(); 4152 } 4153 EXPORT_SYMBOL(xfrm_if_unregister_cb); 4154 4155 #ifdef CONFIG_XFRM_STATISTICS xfrm_statistics_init(struct net * net)4156 static int __net_init xfrm_statistics_init(struct net *net) 4157 { 4158 int rv; 4159 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 4160 if (!net->mib.xfrm_statistics) 4161 return -ENOMEM; 4162 rv = xfrm_proc_init(net); 4163 if (rv < 0) 4164 free_percpu(net->mib.xfrm_statistics); 4165 return rv; 4166 } 4167 xfrm_statistics_fini(struct net * net)4168 static void xfrm_statistics_fini(struct net *net) 4169 { 4170 xfrm_proc_fini(net); 4171 free_percpu(net->mib.xfrm_statistics); 4172 } 4173 #else xfrm_statistics_init(struct net * net)4174 static int __net_init xfrm_statistics_init(struct net *net) 4175 { 4176 return 0; 4177 } 4178 xfrm_statistics_fini(struct net * net)4179 static void xfrm_statistics_fini(struct net *net) 4180 { 4181 } 4182 #endif 4183 xfrm_policy_init(struct net * net)4184 static int __net_init xfrm_policy_init(struct net *net) 4185 { 4186 unsigned int hmask, sz; 4187 int dir, err; 4188 4189 if (net_eq(net, &init_net)) { 4190 xfrm_dst_cache = KMEM_CACHE(xfrm_dst, SLAB_HWCACHE_ALIGN | SLAB_PANIC); 4191 err = rhashtable_init(&xfrm_policy_inexact_table, 4192 &xfrm_pol_inexact_params); 4193 BUG_ON(err); 4194 } 4195 4196 hmask = 8 - 1; 4197 sz = (hmask+1) * sizeof(struct hlist_head); 4198 4199 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 4200 if (!net->xfrm.policy_byidx) 4201 goto out_byidx; 4202 net->xfrm.policy_idx_hmask = hmask; 4203 4204 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4205 struct xfrm_policy_hash *htab; 4206 4207 net->xfrm.policy_count[dir] = 0; 4208 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 4209 4210 htab = &net->xfrm.policy_bydst[dir]; 4211 htab->table = xfrm_hash_alloc(sz); 4212 if (!htab->table) 4213 goto out_bydst; 4214 htab->hmask = hmask; 4215 htab->dbits4 = 32; 4216 htab->sbits4 = 32; 4217 htab->dbits6 = 128; 4218 htab->sbits6 = 128; 4219 } 4220 net->xfrm.policy_hthresh.lbits4 = 32; 4221 net->xfrm.policy_hthresh.rbits4 = 32; 4222 net->xfrm.policy_hthresh.lbits6 = 128; 4223 net->xfrm.policy_hthresh.rbits6 = 128; 4224 4225 seqlock_init(&net->xfrm.policy_hthresh.lock); 4226 4227 INIT_LIST_HEAD(&net->xfrm.policy_all); 4228 INIT_LIST_HEAD(&net->xfrm.inexact_bins); 4229 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 4230 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 4231 return 0; 4232 4233 out_bydst: 4234 for (dir--; dir >= 0; dir--) { 4235 struct xfrm_policy_hash *htab; 4236 4237 htab = &net->xfrm.policy_bydst[dir]; 4238 xfrm_hash_free(htab->table, sz); 4239 } 4240 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4241 out_byidx: 4242 return -ENOMEM; 4243 } 4244 xfrm_policy_fini(struct net * net)4245 static void xfrm_policy_fini(struct net *net) 4246 { 4247 struct xfrm_pol_inexact_bin *b, *t; 4248 unsigned int sz; 4249 int dir; 4250 4251 flush_work(&net->xfrm.policy_hash_work); 4252 #ifdef CONFIG_XFRM_SUB_POLICY 4253 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 4254 #endif 4255 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 4256 4257 WARN_ON(!list_empty(&net->xfrm.policy_all)); 4258 4259 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 4260 struct xfrm_policy_hash *htab; 4261 4262 htab = &net->xfrm.policy_bydst[dir]; 4263 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 4264 WARN_ON(!hlist_empty(htab->table)); 4265 xfrm_hash_free(htab->table, sz); 4266 } 4267 4268 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 4269 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 4270 xfrm_hash_free(net->xfrm.policy_byidx, sz); 4271 4272 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 4273 list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins) 4274 __xfrm_policy_inexact_prune_bin(b, true); 4275 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 4276 } 4277 xfrm_net_init(struct net * net)4278 static int __net_init xfrm_net_init(struct net *net) 4279 { 4280 int rv; 4281 4282 /* Initialize the per-net locks here */ 4283 spin_lock_init(&net->xfrm.xfrm_state_lock); 4284 spin_lock_init(&net->xfrm.xfrm_policy_lock); 4285 seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock); 4286 mutex_init(&net->xfrm.xfrm_cfg_mutex); 4287 net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT; 4288 net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT; 4289 net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT; 4290 4291 rv = xfrm_statistics_init(net); 4292 if (rv < 0) 4293 goto out_statistics; 4294 rv = xfrm_state_init(net); 4295 if (rv < 0) 4296 goto out_state; 4297 rv = xfrm_policy_init(net); 4298 if (rv < 0) 4299 goto out_policy; 4300 rv = xfrm_sysctl_init(net); 4301 if (rv < 0) 4302 goto out_sysctl; 4303 4304 rv = xfrm_nat_keepalive_net_init(net); 4305 if (rv < 0) 4306 goto out_nat_keepalive; 4307 4308 return 0; 4309 4310 out_nat_keepalive: 4311 xfrm_sysctl_fini(net); 4312 out_sysctl: 4313 xfrm_policy_fini(net); 4314 out_policy: 4315 xfrm_state_fini(net); 4316 out_state: 4317 xfrm_statistics_fini(net); 4318 out_statistics: 4319 return rv; 4320 } 4321 xfrm_net_exit(struct net * net)4322 static void __net_exit xfrm_net_exit(struct net *net) 4323 { 4324 xfrm_nat_keepalive_net_fini(net); 4325 xfrm_sysctl_fini(net); 4326 xfrm_policy_fini(net); 4327 xfrm_state_fini(net); 4328 xfrm_statistics_fini(net); 4329 } 4330 4331 static struct pernet_operations __net_initdata xfrm_net_ops = { 4332 .init = xfrm_net_init, 4333 .exit = xfrm_net_exit, 4334 }; 4335 4336 static const struct flow_dissector_key xfrm_flow_dissector_keys[] = { 4337 { 4338 .key_id = FLOW_DISSECTOR_KEY_CONTROL, 4339 .offset = offsetof(struct xfrm_flow_keys, control), 4340 }, 4341 { 4342 .key_id = FLOW_DISSECTOR_KEY_BASIC, 4343 .offset = offsetof(struct xfrm_flow_keys, basic), 4344 }, 4345 { 4346 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS, 4347 .offset = offsetof(struct xfrm_flow_keys, addrs.ipv4), 4348 }, 4349 { 4350 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS, 4351 .offset = offsetof(struct xfrm_flow_keys, addrs.ipv6), 4352 }, 4353 { 4354 .key_id = FLOW_DISSECTOR_KEY_PORTS, 4355 .offset = offsetof(struct xfrm_flow_keys, ports), 4356 }, 4357 { 4358 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID, 4359 .offset = offsetof(struct xfrm_flow_keys, gre), 4360 }, 4361 { 4362 .key_id = FLOW_DISSECTOR_KEY_IP, 4363 .offset = offsetof(struct xfrm_flow_keys, ip), 4364 }, 4365 { 4366 .key_id = FLOW_DISSECTOR_KEY_ICMP, 4367 .offset = offsetof(struct xfrm_flow_keys, icmp), 4368 }, 4369 }; 4370 xfrm_init(void)4371 void __init xfrm_init(void) 4372 { 4373 skb_flow_dissector_init(&xfrm_session_dissector, 4374 xfrm_flow_dissector_keys, 4375 ARRAY_SIZE(xfrm_flow_dissector_keys)); 4376 4377 register_pernet_subsys(&xfrm_net_ops); 4378 xfrm_dev_init(); 4379 xfrm_input_init(); 4380 4381 #ifdef CONFIG_XFRM_ESPINTCP 4382 espintcp_init(); 4383 #endif 4384 4385 register_xfrm_state_bpf(); 4386 xfrm_nat_keepalive_init(AF_INET); 4387 } 4388 4389 #ifdef CONFIG_AUDITSYSCALL xfrm_audit_common_policyinfo(struct xfrm_policy * xp,struct audit_buffer * audit_buf)4390 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 4391 struct audit_buffer *audit_buf) 4392 { 4393 struct xfrm_sec_ctx *ctx = xp->security; 4394 struct xfrm_selector *sel = &xp->selector; 4395 4396 if (ctx) 4397 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 4398 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 4399 4400 switch (sel->family) { 4401 case AF_INET: 4402 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 4403 if (sel->prefixlen_s != 32) 4404 audit_log_format(audit_buf, " src_prefixlen=%d", 4405 sel->prefixlen_s); 4406 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 4407 if (sel->prefixlen_d != 32) 4408 audit_log_format(audit_buf, " dst_prefixlen=%d", 4409 sel->prefixlen_d); 4410 break; 4411 case AF_INET6: 4412 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 4413 if (sel->prefixlen_s != 128) 4414 audit_log_format(audit_buf, " src_prefixlen=%d", 4415 sel->prefixlen_s); 4416 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 4417 if (sel->prefixlen_d != 128) 4418 audit_log_format(audit_buf, " dst_prefixlen=%d", 4419 sel->prefixlen_d); 4420 break; 4421 } 4422 } 4423 xfrm_audit_policy_add(struct xfrm_policy * xp,int result,bool task_valid)4424 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 4425 { 4426 struct audit_buffer *audit_buf; 4427 4428 audit_buf = xfrm_audit_start("SPD-add"); 4429 if (audit_buf == NULL) 4430 return; 4431 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4432 audit_log_format(audit_buf, " res=%u", result); 4433 xfrm_audit_common_policyinfo(xp, audit_buf); 4434 audit_log_end(audit_buf); 4435 } 4436 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 4437 xfrm_audit_policy_delete(struct xfrm_policy * xp,int result,bool task_valid)4438 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 4439 bool task_valid) 4440 { 4441 struct audit_buffer *audit_buf; 4442 4443 audit_buf = xfrm_audit_start("SPD-delete"); 4444 if (audit_buf == NULL) 4445 return; 4446 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 4447 audit_log_format(audit_buf, " res=%u", result); 4448 xfrm_audit_common_policyinfo(xp, audit_buf); 4449 audit_log_end(audit_buf); 4450 } 4451 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 4452 #endif 4453 4454 #ifdef CONFIG_XFRM_MIGRATE xfrm_migrate_policy_find(const struct xfrm_selector * sel,u8 dir,u8 type,struct net * net,u32 if_id)4455 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 4456 u8 dir, u8 type, struct net *net, u32 if_id) 4457 { 4458 struct xfrm_policy *pol; 4459 struct flowi fl; 4460 4461 memset(&fl, 0, sizeof(fl)); 4462 4463 fl.flowi_proto = sel->proto; 4464 4465 switch (sel->family) { 4466 case AF_INET: 4467 fl.u.ip4.saddr = sel->saddr.a4; 4468 fl.u.ip4.daddr = sel->daddr.a4; 4469 if (sel->proto == IPSEC_ULPROTO_ANY) 4470 break; 4471 fl.u.flowi4_oif = sel->ifindex; 4472 fl.u.ip4.fl4_sport = sel->sport; 4473 fl.u.ip4.fl4_dport = sel->dport; 4474 break; 4475 case AF_INET6: 4476 fl.u.ip6.saddr = sel->saddr.in6; 4477 fl.u.ip6.daddr = sel->daddr.in6; 4478 if (sel->proto == IPSEC_ULPROTO_ANY) 4479 break; 4480 fl.u.flowi6_oif = sel->ifindex; 4481 fl.u.ip6.fl4_sport = sel->sport; 4482 fl.u.ip6.fl4_dport = sel->dport; 4483 break; 4484 default: 4485 return ERR_PTR(-EAFNOSUPPORT); 4486 } 4487 4488 rcu_read_lock(); 4489 4490 pol = xfrm_policy_lookup_bytype(net, type, &fl, sel->family, dir, if_id); 4491 if (IS_ERR_OR_NULL(pol)) 4492 goto out_unlock; 4493 4494 if (!xfrm_pol_hold_rcu(pol)) 4495 pol = NULL; 4496 out_unlock: 4497 rcu_read_unlock(); 4498 return pol; 4499 } 4500 migrate_tmpl_match(const struct xfrm_migrate * m,const struct xfrm_tmpl * t)4501 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 4502 { 4503 int match = 0; 4504 4505 if (t->mode == m->mode && t->id.proto == m->proto && 4506 (m->reqid == 0 || t->reqid == m->reqid)) { 4507 switch (t->mode) { 4508 case XFRM_MODE_TUNNEL: 4509 case XFRM_MODE_BEET: 4510 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 4511 m->old_family) && 4512 xfrm_addr_equal(&t->saddr, &m->old_saddr, 4513 m->old_family)) { 4514 match = 1; 4515 } 4516 break; 4517 case XFRM_MODE_TRANSPORT: 4518 /* in case of transport mode, template does not store 4519 any IP addresses, hence we just compare mode and 4520 protocol */ 4521 match = 1; 4522 break; 4523 default: 4524 break; 4525 } 4526 } 4527 return match; 4528 } 4529 4530 /* update endpoint address(es) of template(s) */ xfrm_policy_migrate(struct xfrm_policy * pol,struct xfrm_migrate * m,int num_migrate,struct netlink_ext_ack * extack)4531 static int xfrm_policy_migrate(struct xfrm_policy *pol, 4532 struct xfrm_migrate *m, int num_migrate, 4533 struct netlink_ext_ack *extack) 4534 { 4535 struct xfrm_migrate *mp; 4536 int i, j, n = 0; 4537 4538 write_lock_bh(&pol->lock); 4539 if (unlikely(pol->walk.dead)) { 4540 /* target policy has been deleted */ 4541 NL_SET_ERR_MSG(extack, "Target policy not found"); 4542 write_unlock_bh(&pol->lock); 4543 return -ENOENT; 4544 } 4545 4546 for (i = 0; i < pol->xfrm_nr; i++) { 4547 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 4548 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 4549 continue; 4550 n++; 4551 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 4552 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 4553 continue; 4554 /* update endpoints */ 4555 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 4556 sizeof(pol->xfrm_vec[i].id.daddr)); 4557 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 4558 sizeof(pol->xfrm_vec[i].saddr)); 4559 pol->xfrm_vec[i].encap_family = mp->new_family; 4560 /* flush bundles */ 4561 atomic_inc(&pol->genid); 4562 } 4563 } 4564 4565 write_unlock_bh(&pol->lock); 4566 4567 if (!n) 4568 return -ENODATA; 4569 4570 return 0; 4571 } 4572 xfrm_migrate_check(const struct xfrm_migrate * m,int num_migrate,struct netlink_ext_ack * extack)4573 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate, 4574 struct netlink_ext_ack *extack) 4575 { 4576 int i, j; 4577 4578 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) { 4579 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)"); 4580 return -EINVAL; 4581 } 4582 4583 for (i = 0; i < num_migrate; i++) { 4584 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 4585 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) { 4586 NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null"); 4587 return -EINVAL; 4588 } 4589 4590 /* check if there is any duplicated entry */ 4591 for (j = i + 1; j < num_migrate; j++) { 4592 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 4593 sizeof(m[i].old_daddr)) && 4594 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 4595 sizeof(m[i].old_saddr)) && 4596 m[i].proto == m[j].proto && 4597 m[i].mode == m[j].mode && 4598 m[i].reqid == m[j].reqid && 4599 m[i].old_family == m[j].old_family) { 4600 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique"); 4601 return -EINVAL; 4602 } 4603 } 4604 } 4605 4606 return 0; 4607 } 4608 xfrm_migrate(const struct xfrm_selector * sel,u8 dir,u8 type,struct xfrm_migrate * m,int num_migrate,struct xfrm_kmaddress * k,struct net * net,struct xfrm_encap_tmpl * encap,u32 if_id,struct netlink_ext_ack * extack)4609 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 4610 struct xfrm_migrate *m, int num_migrate, 4611 struct xfrm_kmaddress *k, struct net *net, 4612 struct xfrm_encap_tmpl *encap, u32 if_id, 4613 struct netlink_ext_ack *extack) 4614 { 4615 int i, err, nx_cur = 0, nx_new = 0; 4616 struct xfrm_policy *pol = NULL; 4617 struct xfrm_state *x, *xc; 4618 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 4619 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 4620 struct xfrm_migrate *mp; 4621 4622 /* Stage 0 - sanity checks */ 4623 err = xfrm_migrate_check(m, num_migrate, extack); 4624 if (err < 0) 4625 goto out; 4626 4627 if (dir >= XFRM_POLICY_MAX) { 4628 NL_SET_ERR_MSG(extack, "Invalid policy direction"); 4629 err = -EINVAL; 4630 goto out; 4631 } 4632 4633 /* Stage 1 - find policy */ 4634 pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id); 4635 if (IS_ERR_OR_NULL(pol)) { 4636 NL_SET_ERR_MSG(extack, "Target policy not found"); 4637 err = IS_ERR(pol) ? PTR_ERR(pol) : -ENOENT; 4638 goto out; 4639 } 4640 4641 /* Stage 2 - find and update state(s) */ 4642 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 4643 if ((x = xfrm_migrate_state_find(mp, net, if_id))) { 4644 x_cur[nx_cur] = x; 4645 nx_cur++; 4646 xc = xfrm_state_migrate(x, mp, encap); 4647 if (xc) { 4648 x_new[nx_new] = xc; 4649 nx_new++; 4650 } else { 4651 err = -ENODATA; 4652 goto restore_state; 4653 } 4654 } 4655 } 4656 4657 /* Stage 3 - update policy */ 4658 err = xfrm_policy_migrate(pol, m, num_migrate, extack); 4659 if (err < 0) 4660 goto restore_state; 4661 4662 /* Stage 4 - delete old state(s) */ 4663 if (nx_cur) { 4664 xfrm_states_put(x_cur, nx_cur); 4665 xfrm_states_delete(x_cur, nx_cur); 4666 } 4667 4668 /* Stage 5 - announce */ 4669 km_migrate(sel, dir, type, m, num_migrate, k, encap); 4670 4671 xfrm_pol_put(pol); 4672 4673 return 0; 4674 out: 4675 return err; 4676 4677 restore_state: 4678 if (pol) 4679 xfrm_pol_put(pol); 4680 if (nx_cur) 4681 xfrm_states_put(x_cur, nx_cur); 4682 if (nx_new) 4683 xfrm_states_delete(x_new, nx_new); 4684 4685 return err; 4686 } 4687 EXPORT_SYMBOL(xfrm_migrate); 4688 #endif 4689