1 /* 2 * xfrm_policy.c 3 * 4 * Changes: 5 * Mitsuru KANDA @USAGI 6 * Kazunori MIYAZAWA @USAGI 7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 8 * IPv6 support 9 * Kazunori MIYAZAWA @USAGI 10 * YOSHIFUJI Hideaki 11 * Split up af-specific portion 12 * Derek Atkins <derek@ihtfp.com> Add the post_input processor 13 * 14 */ 15 16 #include <linux/err.h> 17 #include <linux/slab.h> 18 #include <linux/kmod.h> 19 #include <linux/list.h> 20 #include <linux/spinlock.h> 21 #include <linux/workqueue.h> 22 #include <linux/notifier.h> 23 #include <linux/netdevice.h> 24 #include <linux/netfilter.h> 25 #include <linux/module.h> 26 #include <linux/cache.h> 27 #include <linux/cpu.h> 28 #include <linux/audit.h> 29 #include <net/dst.h> 30 #include <net/flow.h> 31 #include <net/xfrm.h> 32 #include <net/ip.h> 33 #ifdef CONFIG_XFRM_STATISTICS 34 #include <net/snmp.h> 35 #endif 36 37 #include "xfrm_hash.h" 38 39 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 40 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 41 #define XFRM_MAX_QUEUE_LEN 100 42 43 struct xfrm_flo { 44 struct dst_entry *dst_orig; 45 u8 flags; 46 }; 47 48 static DEFINE_PER_CPU(struct xfrm_dst *, xfrm_last_dst); 49 static struct work_struct *xfrm_pcpu_work __read_mostly; 50 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 51 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 52 __read_mostly; 53 54 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 55 static __read_mostly seqcount_t xfrm_policy_hash_generation; 56 57 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 58 static int stale_bundle(struct dst_entry *dst); 59 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 60 static void xfrm_policy_queue_process(struct timer_list *t); 61 62 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 63 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 64 int dir); 65 66 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 67 { 68 return refcount_inc_not_zero(&policy->refcnt); 69 } 70 71 static inline bool 72 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 73 { 74 const struct flowi4 *fl4 = &fl->u.ip4; 75 76 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 77 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 78 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 79 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 80 (fl4->flowi4_proto == sel->proto || !sel->proto) && 81 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 82 } 83 84 static inline bool 85 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 86 { 87 const struct flowi6 *fl6 = &fl->u.ip6; 88 89 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 90 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 91 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 92 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 93 (fl6->flowi6_proto == sel->proto || !sel->proto) && 94 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 95 } 96 97 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 98 unsigned short family) 99 { 100 switch (family) { 101 case AF_INET: 102 return __xfrm4_selector_match(sel, fl); 103 case AF_INET6: 104 return __xfrm6_selector_match(sel, fl); 105 } 106 return false; 107 } 108 109 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 110 { 111 const struct xfrm_policy_afinfo *afinfo; 112 113 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 114 return NULL; 115 rcu_read_lock(); 116 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 117 if (unlikely(!afinfo)) 118 rcu_read_unlock(); 119 return afinfo; 120 } 121 122 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 123 const xfrm_address_t *saddr, 124 const xfrm_address_t *daddr, 125 int family, u32 mark) 126 { 127 const struct xfrm_policy_afinfo *afinfo; 128 struct dst_entry *dst; 129 130 afinfo = xfrm_policy_get_afinfo(family); 131 if (unlikely(afinfo == NULL)) 132 return ERR_PTR(-EAFNOSUPPORT); 133 134 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 135 136 rcu_read_unlock(); 137 138 return dst; 139 } 140 EXPORT_SYMBOL(__xfrm_dst_lookup); 141 142 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 143 int tos, int oif, 144 xfrm_address_t *prev_saddr, 145 xfrm_address_t *prev_daddr, 146 int family, u32 mark) 147 { 148 struct net *net = xs_net(x); 149 xfrm_address_t *saddr = &x->props.saddr; 150 xfrm_address_t *daddr = &x->id.daddr; 151 struct dst_entry *dst; 152 153 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 154 saddr = x->coaddr; 155 daddr = prev_daddr; 156 } 157 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 158 saddr = prev_saddr; 159 daddr = x->coaddr; 160 } 161 162 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 163 164 if (!IS_ERR(dst)) { 165 if (prev_saddr != saddr) 166 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 167 if (prev_daddr != daddr) 168 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 169 } 170 171 return dst; 172 } 173 174 static inline unsigned long make_jiffies(long secs) 175 { 176 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 177 return MAX_SCHEDULE_TIMEOUT-1; 178 else 179 return secs*HZ; 180 } 181 182 static void xfrm_policy_timer(struct timer_list *t) 183 { 184 struct xfrm_policy *xp = from_timer(xp, t, timer); 185 unsigned long now = get_seconds(); 186 long next = LONG_MAX; 187 int warn = 0; 188 int dir; 189 190 read_lock(&xp->lock); 191 192 if (unlikely(xp->walk.dead)) 193 goto out; 194 195 dir = xfrm_policy_id2dir(xp->index); 196 197 if (xp->lft.hard_add_expires_seconds) { 198 long tmo = xp->lft.hard_add_expires_seconds + 199 xp->curlft.add_time - now; 200 if (tmo <= 0) 201 goto expired; 202 if (tmo < next) 203 next = tmo; 204 } 205 if (xp->lft.hard_use_expires_seconds) { 206 long tmo = xp->lft.hard_use_expires_seconds + 207 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 208 if (tmo <= 0) 209 goto expired; 210 if (tmo < next) 211 next = tmo; 212 } 213 if (xp->lft.soft_add_expires_seconds) { 214 long tmo = xp->lft.soft_add_expires_seconds + 215 xp->curlft.add_time - now; 216 if (tmo <= 0) { 217 warn = 1; 218 tmo = XFRM_KM_TIMEOUT; 219 } 220 if (tmo < next) 221 next = tmo; 222 } 223 if (xp->lft.soft_use_expires_seconds) { 224 long tmo = xp->lft.soft_use_expires_seconds + 225 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 226 if (tmo <= 0) { 227 warn = 1; 228 tmo = XFRM_KM_TIMEOUT; 229 } 230 if (tmo < next) 231 next = tmo; 232 } 233 234 if (warn) 235 km_policy_expired(xp, dir, 0, 0); 236 if (next != LONG_MAX && 237 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 238 xfrm_pol_hold(xp); 239 240 out: 241 read_unlock(&xp->lock); 242 xfrm_pol_put(xp); 243 return; 244 245 expired: 246 read_unlock(&xp->lock); 247 if (!xfrm_policy_delete(xp, dir)) 248 km_policy_expired(xp, dir, 1, 0); 249 xfrm_pol_put(xp); 250 } 251 252 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 253 * SPD calls. 254 */ 255 256 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 257 { 258 struct xfrm_policy *policy; 259 260 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 261 262 if (policy) { 263 write_pnet(&policy->xp_net, net); 264 INIT_LIST_HEAD(&policy->walk.all); 265 INIT_HLIST_NODE(&policy->bydst); 266 INIT_HLIST_NODE(&policy->byidx); 267 rwlock_init(&policy->lock); 268 refcount_set(&policy->refcnt, 1); 269 skb_queue_head_init(&policy->polq.hold_queue); 270 timer_setup(&policy->timer, xfrm_policy_timer, 0); 271 timer_setup(&policy->polq.hold_timer, 272 xfrm_policy_queue_process, 0); 273 } 274 return policy; 275 } 276 EXPORT_SYMBOL(xfrm_policy_alloc); 277 278 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 279 { 280 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 281 282 security_xfrm_policy_free(policy->security); 283 kfree(policy); 284 } 285 286 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 287 288 void xfrm_policy_destroy(struct xfrm_policy *policy) 289 { 290 BUG_ON(!policy->walk.dead); 291 292 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 293 BUG(); 294 295 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 296 } 297 EXPORT_SYMBOL(xfrm_policy_destroy); 298 299 /* Rule must be locked. Release descendant resources, announce 300 * entry dead. The rule must be unlinked from lists to the moment. 301 */ 302 303 static void xfrm_policy_kill(struct xfrm_policy *policy) 304 { 305 policy->walk.dead = 1; 306 307 atomic_inc(&policy->genid); 308 309 if (del_timer(&policy->polq.hold_timer)) 310 xfrm_pol_put(policy); 311 skb_queue_purge(&policy->polq.hold_queue); 312 313 if (del_timer(&policy->timer)) 314 xfrm_pol_put(policy); 315 316 xfrm_pol_put(policy); 317 } 318 319 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 320 321 static inline unsigned int idx_hash(struct net *net, u32 index) 322 { 323 return __idx_hash(index, net->xfrm.policy_idx_hmask); 324 } 325 326 /* calculate policy hash thresholds */ 327 static void __get_hash_thresh(struct net *net, 328 unsigned short family, int dir, 329 u8 *dbits, u8 *sbits) 330 { 331 switch (family) { 332 case AF_INET: 333 *dbits = net->xfrm.policy_bydst[dir].dbits4; 334 *sbits = net->xfrm.policy_bydst[dir].sbits4; 335 break; 336 337 case AF_INET6: 338 *dbits = net->xfrm.policy_bydst[dir].dbits6; 339 *sbits = net->xfrm.policy_bydst[dir].sbits6; 340 break; 341 342 default: 343 *dbits = 0; 344 *sbits = 0; 345 } 346 } 347 348 static struct hlist_head *policy_hash_bysel(struct net *net, 349 const struct xfrm_selector *sel, 350 unsigned short family, int dir) 351 { 352 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 353 unsigned int hash; 354 u8 dbits; 355 u8 sbits; 356 357 __get_hash_thresh(net, family, dir, &dbits, &sbits); 358 hash = __sel_hash(sel, family, hmask, dbits, sbits); 359 360 if (hash == hmask + 1) 361 return &net->xfrm.policy_inexact[dir]; 362 363 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 364 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 365 } 366 367 static struct hlist_head *policy_hash_direct(struct net *net, 368 const xfrm_address_t *daddr, 369 const xfrm_address_t *saddr, 370 unsigned short family, int dir) 371 { 372 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 373 unsigned int hash; 374 u8 dbits; 375 u8 sbits; 376 377 __get_hash_thresh(net, family, dir, &dbits, &sbits); 378 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 379 380 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 381 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 382 } 383 384 static void xfrm_dst_hash_transfer(struct net *net, 385 struct hlist_head *list, 386 struct hlist_head *ndsttable, 387 unsigned int nhashmask, 388 int dir) 389 { 390 struct hlist_node *tmp, *entry0 = NULL; 391 struct xfrm_policy *pol; 392 unsigned int h0 = 0; 393 u8 dbits; 394 u8 sbits; 395 396 redo: 397 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 398 unsigned int h; 399 400 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 401 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 402 pol->family, nhashmask, dbits, sbits); 403 if (!entry0) { 404 hlist_del_rcu(&pol->bydst); 405 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 406 h0 = h; 407 } else { 408 if (h != h0) 409 continue; 410 hlist_del_rcu(&pol->bydst); 411 hlist_add_behind_rcu(&pol->bydst, entry0); 412 } 413 entry0 = &pol->bydst; 414 } 415 if (!hlist_empty(list)) { 416 entry0 = NULL; 417 goto redo; 418 } 419 } 420 421 static void xfrm_idx_hash_transfer(struct hlist_head *list, 422 struct hlist_head *nidxtable, 423 unsigned int nhashmask) 424 { 425 struct hlist_node *tmp; 426 struct xfrm_policy *pol; 427 428 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 429 unsigned int h; 430 431 h = __idx_hash(pol->index, nhashmask); 432 hlist_add_head(&pol->byidx, nidxtable+h); 433 } 434 } 435 436 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 437 { 438 return ((old_hmask + 1) << 1) - 1; 439 } 440 441 static void xfrm_bydst_resize(struct net *net, int dir) 442 { 443 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 444 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 445 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 446 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 447 struct hlist_head *odst; 448 int i; 449 450 if (!ndst) 451 return; 452 453 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 454 write_seqcount_begin(&xfrm_policy_hash_generation); 455 456 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 457 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 458 459 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 460 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 461 462 for (i = hmask; i >= 0; i--) 463 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 464 465 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 466 net->xfrm.policy_bydst[dir].hmask = nhashmask; 467 468 write_seqcount_end(&xfrm_policy_hash_generation); 469 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 470 471 synchronize_rcu(); 472 473 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 474 } 475 476 static void xfrm_byidx_resize(struct net *net, int total) 477 { 478 unsigned int hmask = net->xfrm.policy_idx_hmask; 479 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 480 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 481 struct hlist_head *oidx = net->xfrm.policy_byidx; 482 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 483 int i; 484 485 if (!nidx) 486 return; 487 488 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 489 490 for (i = hmask; i >= 0; i--) 491 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 492 493 net->xfrm.policy_byidx = nidx; 494 net->xfrm.policy_idx_hmask = nhashmask; 495 496 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 497 498 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 499 } 500 501 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 502 { 503 unsigned int cnt = net->xfrm.policy_count[dir]; 504 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 505 506 if (total) 507 *total += cnt; 508 509 if ((hmask + 1) < xfrm_policy_hashmax && 510 cnt > hmask) 511 return 1; 512 513 return 0; 514 } 515 516 static inline int xfrm_byidx_should_resize(struct net *net, int total) 517 { 518 unsigned int hmask = net->xfrm.policy_idx_hmask; 519 520 if ((hmask + 1) < xfrm_policy_hashmax && 521 total > hmask) 522 return 1; 523 524 return 0; 525 } 526 527 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 528 { 529 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 530 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 531 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 532 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 533 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 534 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 535 si->spdhcnt = net->xfrm.policy_idx_hmask; 536 si->spdhmcnt = xfrm_policy_hashmax; 537 } 538 EXPORT_SYMBOL(xfrm_spd_getinfo); 539 540 static DEFINE_MUTEX(hash_resize_mutex); 541 static void xfrm_hash_resize(struct work_struct *work) 542 { 543 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 544 int dir, total; 545 546 mutex_lock(&hash_resize_mutex); 547 548 total = 0; 549 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 550 if (xfrm_bydst_should_resize(net, dir, &total)) 551 xfrm_bydst_resize(net, dir); 552 } 553 if (xfrm_byidx_should_resize(net, total)) 554 xfrm_byidx_resize(net, total); 555 556 mutex_unlock(&hash_resize_mutex); 557 } 558 559 static void xfrm_hash_rebuild(struct work_struct *work) 560 { 561 struct net *net = container_of(work, struct net, 562 xfrm.policy_hthresh.work); 563 unsigned int hmask; 564 struct xfrm_policy *pol; 565 struct xfrm_policy *policy; 566 struct hlist_head *chain; 567 struct hlist_head *odst; 568 struct hlist_node *newpos; 569 int i; 570 int dir; 571 unsigned seq; 572 u8 lbits4, rbits4, lbits6, rbits6; 573 574 mutex_lock(&hash_resize_mutex); 575 576 /* read selector prefixlen thresholds */ 577 do { 578 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 579 580 lbits4 = net->xfrm.policy_hthresh.lbits4; 581 rbits4 = net->xfrm.policy_hthresh.rbits4; 582 lbits6 = net->xfrm.policy_hthresh.lbits6; 583 rbits6 = net->xfrm.policy_hthresh.rbits6; 584 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 585 586 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 587 588 /* reset the bydst and inexact table in all directions */ 589 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 590 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 591 hmask = net->xfrm.policy_bydst[dir].hmask; 592 odst = net->xfrm.policy_bydst[dir].table; 593 for (i = hmask; i >= 0; i--) 594 INIT_HLIST_HEAD(odst + i); 595 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 596 /* dir out => dst = remote, src = local */ 597 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 598 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 599 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 600 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 601 } else { 602 /* dir in/fwd => dst = local, src = remote */ 603 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 604 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 605 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 606 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 607 } 608 } 609 610 /* re-insert all policies by order of creation */ 611 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 612 if (policy->walk.dead || 613 xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) { 614 /* skip socket policies */ 615 continue; 616 } 617 newpos = NULL; 618 chain = policy_hash_bysel(net, &policy->selector, 619 policy->family, 620 xfrm_policy_id2dir(policy->index)); 621 hlist_for_each_entry(pol, chain, bydst) { 622 if (policy->priority >= pol->priority) 623 newpos = &pol->bydst; 624 else 625 break; 626 } 627 if (newpos) 628 hlist_add_behind(&policy->bydst, newpos); 629 else 630 hlist_add_head(&policy->bydst, chain); 631 } 632 633 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 634 635 mutex_unlock(&hash_resize_mutex); 636 } 637 638 void xfrm_policy_hash_rebuild(struct net *net) 639 { 640 schedule_work(&net->xfrm.policy_hthresh.work); 641 } 642 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 643 644 /* Generate new index... KAME seems to generate them ordered by cost 645 * of an absolute inpredictability of ordering of rules. This will not pass. */ 646 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 647 { 648 static u32 idx_generator; 649 650 for (;;) { 651 struct hlist_head *list; 652 struct xfrm_policy *p; 653 u32 idx; 654 int found; 655 656 if (!index) { 657 idx = (idx_generator | dir); 658 idx_generator += 8; 659 } else { 660 idx = index; 661 index = 0; 662 } 663 664 if (idx == 0) 665 idx = 8; 666 list = net->xfrm.policy_byidx + idx_hash(net, idx); 667 found = 0; 668 hlist_for_each_entry(p, list, byidx) { 669 if (p->index == idx) { 670 found = 1; 671 break; 672 } 673 } 674 if (!found) 675 return idx; 676 } 677 } 678 679 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 680 { 681 u32 *p1 = (u32 *) s1; 682 u32 *p2 = (u32 *) s2; 683 int len = sizeof(struct xfrm_selector) / sizeof(u32); 684 int i; 685 686 for (i = 0; i < len; i++) { 687 if (p1[i] != p2[i]) 688 return 1; 689 } 690 691 return 0; 692 } 693 694 static void xfrm_policy_requeue(struct xfrm_policy *old, 695 struct xfrm_policy *new) 696 { 697 struct xfrm_policy_queue *pq = &old->polq; 698 struct sk_buff_head list; 699 700 if (skb_queue_empty(&pq->hold_queue)) 701 return; 702 703 __skb_queue_head_init(&list); 704 705 spin_lock_bh(&pq->hold_queue.lock); 706 skb_queue_splice_init(&pq->hold_queue, &list); 707 if (del_timer(&pq->hold_timer)) 708 xfrm_pol_put(old); 709 spin_unlock_bh(&pq->hold_queue.lock); 710 711 pq = &new->polq; 712 713 spin_lock_bh(&pq->hold_queue.lock); 714 skb_queue_splice(&list, &pq->hold_queue); 715 pq->timeout = XFRM_QUEUE_TMO_MIN; 716 if (!mod_timer(&pq->hold_timer, jiffies)) 717 xfrm_pol_hold(new); 718 spin_unlock_bh(&pq->hold_queue.lock); 719 } 720 721 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 722 struct xfrm_policy *pol) 723 { 724 u32 mark = policy->mark.v & policy->mark.m; 725 726 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 727 return true; 728 729 if ((mark & pol->mark.m) == pol->mark.v && 730 policy->priority == pol->priority) 731 return true; 732 733 return false; 734 } 735 736 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 737 { 738 struct net *net = xp_net(policy); 739 struct xfrm_policy *pol; 740 struct xfrm_policy *delpol; 741 struct hlist_head *chain; 742 struct hlist_node *newpos; 743 744 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 745 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 746 delpol = NULL; 747 newpos = NULL; 748 hlist_for_each_entry(pol, chain, bydst) { 749 if (pol->type == policy->type && 750 !selector_cmp(&pol->selector, &policy->selector) && 751 xfrm_policy_mark_match(policy, pol) && 752 xfrm_sec_ctx_match(pol->security, policy->security) && 753 !WARN_ON(delpol)) { 754 if (excl) { 755 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 756 return -EEXIST; 757 } 758 delpol = pol; 759 if (policy->priority > pol->priority) 760 continue; 761 } else if (policy->priority >= pol->priority) { 762 newpos = &pol->bydst; 763 continue; 764 } 765 if (delpol) 766 break; 767 } 768 if (newpos) 769 hlist_add_behind(&policy->bydst, newpos); 770 else 771 hlist_add_head(&policy->bydst, chain); 772 __xfrm_policy_link(policy, dir); 773 774 /* After previous checking, family can either be AF_INET or AF_INET6 */ 775 if (policy->family == AF_INET) 776 rt_genid_bump_ipv4(net); 777 else 778 rt_genid_bump_ipv6(net); 779 780 if (delpol) { 781 xfrm_policy_requeue(delpol, policy); 782 __xfrm_policy_unlink(delpol, dir); 783 } 784 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 785 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 786 policy->curlft.add_time = get_seconds(); 787 policy->curlft.use_time = 0; 788 if (!mod_timer(&policy->timer, jiffies + HZ)) 789 xfrm_pol_hold(policy); 790 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 791 792 if (delpol) 793 xfrm_policy_kill(delpol); 794 else if (xfrm_bydst_should_resize(net, dir, NULL)) 795 schedule_work(&net->xfrm.policy_hash_work); 796 797 return 0; 798 } 799 EXPORT_SYMBOL(xfrm_policy_insert); 800 801 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type, 802 int dir, struct xfrm_selector *sel, 803 struct xfrm_sec_ctx *ctx, int delete, 804 int *err) 805 { 806 struct xfrm_policy *pol, *ret; 807 struct hlist_head *chain; 808 809 *err = 0; 810 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 811 chain = policy_hash_bysel(net, sel, sel->family, dir); 812 ret = NULL; 813 hlist_for_each_entry(pol, chain, bydst) { 814 if (pol->type == type && 815 (mark & pol->mark.m) == pol->mark.v && 816 !selector_cmp(sel, &pol->selector) && 817 xfrm_sec_ctx_match(ctx, pol->security)) { 818 xfrm_pol_hold(pol); 819 if (delete) { 820 *err = security_xfrm_policy_delete( 821 pol->security); 822 if (*err) { 823 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 824 return pol; 825 } 826 __xfrm_policy_unlink(pol, dir); 827 } 828 ret = pol; 829 break; 830 } 831 } 832 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 833 834 if (ret && delete) 835 xfrm_policy_kill(ret); 836 return ret; 837 } 838 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 839 840 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type, 841 int dir, u32 id, int delete, int *err) 842 { 843 struct xfrm_policy *pol, *ret; 844 struct hlist_head *chain; 845 846 *err = -ENOENT; 847 if (xfrm_policy_id2dir(id) != dir) 848 return NULL; 849 850 *err = 0; 851 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 852 chain = net->xfrm.policy_byidx + idx_hash(net, id); 853 ret = NULL; 854 hlist_for_each_entry(pol, chain, byidx) { 855 if (pol->type == type && pol->index == id && 856 (mark & pol->mark.m) == pol->mark.v) { 857 xfrm_pol_hold(pol); 858 if (delete) { 859 *err = security_xfrm_policy_delete( 860 pol->security); 861 if (*err) { 862 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 863 return pol; 864 } 865 __xfrm_policy_unlink(pol, dir); 866 } 867 ret = pol; 868 break; 869 } 870 } 871 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 872 873 if (ret && delete) 874 xfrm_policy_kill(ret); 875 return ret; 876 } 877 EXPORT_SYMBOL(xfrm_policy_byid); 878 879 #ifdef CONFIG_SECURITY_NETWORK_XFRM 880 static inline int 881 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 882 { 883 int dir, err = 0; 884 885 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 886 struct xfrm_policy *pol; 887 int i; 888 889 hlist_for_each_entry(pol, 890 &net->xfrm.policy_inexact[dir], bydst) { 891 if (pol->type != type) 892 continue; 893 err = security_xfrm_policy_delete(pol->security); 894 if (err) { 895 xfrm_audit_policy_delete(pol, 0, task_valid); 896 return err; 897 } 898 } 899 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 900 hlist_for_each_entry(pol, 901 net->xfrm.policy_bydst[dir].table + i, 902 bydst) { 903 if (pol->type != type) 904 continue; 905 err = security_xfrm_policy_delete( 906 pol->security); 907 if (err) { 908 xfrm_audit_policy_delete(pol, 0, 909 task_valid); 910 return err; 911 } 912 } 913 } 914 } 915 return err; 916 } 917 #else 918 static inline int 919 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 920 { 921 return 0; 922 } 923 #endif 924 925 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 926 { 927 int dir, err = 0, cnt = 0; 928 929 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 930 931 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 932 if (err) 933 goto out; 934 935 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 936 struct xfrm_policy *pol; 937 int i; 938 939 again1: 940 hlist_for_each_entry(pol, 941 &net->xfrm.policy_inexact[dir], bydst) { 942 if (pol->type != type) 943 continue; 944 __xfrm_policy_unlink(pol, dir); 945 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 946 cnt++; 947 948 xfrm_audit_policy_delete(pol, 1, task_valid); 949 950 xfrm_policy_kill(pol); 951 952 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 953 goto again1; 954 } 955 956 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 957 again2: 958 hlist_for_each_entry(pol, 959 net->xfrm.policy_bydst[dir].table + i, 960 bydst) { 961 if (pol->type != type) 962 continue; 963 __xfrm_policy_unlink(pol, dir); 964 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 965 cnt++; 966 967 xfrm_audit_policy_delete(pol, 1, task_valid); 968 xfrm_policy_kill(pol); 969 970 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 971 goto again2; 972 } 973 } 974 975 } 976 if (!cnt) 977 err = -ESRCH; 978 out: 979 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 980 return err; 981 } 982 EXPORT_SYMBOL(xfrm_policy_flush); 983 984 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 985 int (*func)(struct xfrm_policy *, int, int, void*), 986 void *data) 987 { 988 struct xfrm_policy *pol; 989 struct xfrm_policy_walk_entry *x; 990 int error = 0; 991 992 if (walk->type >= XFRM_POLICY_TYPE_MAX && 993 walk->type != XFRM_POLICY_TYPE_ANY) 994 return -EINVAL; 995 996 if (list_empty(&walk->walk.all) && walk->seq != 0) 997 return 0; 998 999 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1000 if (list_empty(&walk->walk.all)) 1001 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1002 else 1003 x = list_first_entry(&walk->walk.all, 1004 struct xfrm_policy_walk_entry, all); 1005 1006 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1007 if (x->dead) 1008 continue; 1009 pol = container_of(x, struct xfrm_policy, walk); 1010 if (walk->type != XFRM_POLICY_TYPE_ANY && 1011 walk->type != pol->type) 1012 continue; 1013 error = func(pol, xfrm_policy_id2dir(pol->index), 1014 walk->seq, data); 1015 if (error) { 1016 list_move_tail(&walk->walk.all, &x->all); 1017 goto out; 1018 } 1019 walk->seq++; 1020 } 1021 if (walk->seq == 0) { 1022 error = -ENOENT; 1023 goto out; 1024 } 1025 list_del_init(&walk->walk.all); 1026 out: 1027 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1028 return error; 1029 } 1030 EXPORT_SYMBOL(xfrm_policy_walk); 1031 1032 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1033 { 1034 INIT_LIST_HEAD(&walk->walk.all); 1035 walk->walk.dead = 1; 1036 walk->type = type; 1037 walk->seq = 0; 1038 } 1039 EXPORT_SYMBOL(xfrm_policy_walk_init); 1040 1041 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1042 { 1043 if (list_empty(&walk->walk.all)) 1044 return; 1045 1046 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1047 list_del(&walk->walk.all); 1048 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1049 } 1050 EXPORT_SYMBOL(xfrm_policy_walk_done); 1051 1052 /* 1053 * Find policy to apply to this flow. 1054 * 1055 * Returns 0 if policy found, else an -errno. 1056 */ 1057 static int xfrm_policy_match(const struct xfrm_policy *pol, 1058 const struct flowi *fl, 1059 u8 type, u16 family, int dir) 1060 { 1061 const struct xfrm_selector *sel = &pol->selector; 1062 int ret = -ESRCH; 1063 bool match; 1064 1065 if (pol->family != family || 1066 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1067 pol->type != type) 1068 return ret; 1069 1070 match = xfrm_selector_match(sel, fl, family); 1071 if (match) 1072 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1073 dir); 1074 1075 return ret; 1076 } 1077 1078 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 1079 const struct flowi *fl, 1080 u16 family, u8 dir) 1081 { 1082 int err; 1083 struct xfrm_policy *pol, *ret; 1084 const xfrm_address_t *daddr, *saddr; 1085 struct hlist_head *chain; 1086 unsigned int sequence; 1087 u32 priority; 1088 1089 daddr = xfrm_flowi_daddr(fl, family); 1090 saddr = xfrm_flowi_saddr(fl, family); 1091 if (unlikely(!daddr || !saddr)) 1092 return NULL; 1093 1094 rcu_read_lock(); 1095 retry: 1096 do { 1097 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 1098 chain = policy_hash_direct(net, daddr, saddr, family, dir); 1099 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 1100 1101 priority = ~0U; 1102 ret = NULL; 1103 hlist_for_each_entry_rcu(pol, chain, bydst) { 1104 err = xfrm_policy_match(pol, fl, type, family, dir); 1105 if (err) { 1106 if (err == -ESRCH) 1107 continue; 1108 else { 1109 ret = ERR_PTR(err); 1110 goto fail; 1111 } 1112 } else { 1113 ret = pol; 1114 priority = ret->priority; 1115 break; 1116 } 1117 } 1118 chain = &net->xfrm.policy_inexact[dir]; 1119 hlist_for_each_entry_rcu(pol, chain, bydst) { 1120 if ((pol->priority >= priority) && ret) 1121 break; 1122 1123 err = xfrm_policy_match(pol, fl, type, family, dir); 1124 if (err) { 1125 if (err == -ESRCH) 1126 continue; 1127 else { 1128 ret = ERR_PTR(err); 1129 goto fail; 1130 } 1131 } else { 1132 ret = pol; 1133 break; 1134 } 1135 } 1136 1137 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 1138 goto retry; 1139 1140 if (ret && !xfrm_pol_hold_rcu(ret)) 1141 goto retry; 1142 fail: 1143 rcu_read_unlock(); 1144 1145 return ret; 1146 } 1147 1148 static struct xfrm_policy * 1149 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir) 1150 { 1151 #ifdef CONFIG_XFRM_SUB_POLICY 1152 struct xfrm_policy *pol; 1153 1154 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir); 1155 if (pol != NULL) 1156 return pol; 1157 #endif 1158 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir); 1159 } 1160 1161 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 1162 const struct flowi *fl, u16 family) 1163 { 1164 struct xfrm_policy *pol; 1165 1166 rcu_read_lock(); 1167 again: 1168 pol = rcu_dereference(sk->sk_policy[dir]); 1169 if (pol != NULL) { 1170 bool match; 1171 int err = 0; 1172 1173 if (pol->family != family) { 1174 pol = NULL; 1175 goto out; 1176 } 1177 1178 match = xfrm_selector_match(&pol->selector, fl, family); 1179 if (match) { 1180 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) { 1181 pol = NULL; 1182 goto out; 1183 } 1184 err = security_xfrm_policy_lookup(pol->security, 1185 fl->flowi_secid, 1186 dir); 1187 if (!err) { 1188 if (!xfrm_pol_hold_rcu(pol)) 1189 goto again; 1190 } else if (err == -ESRCH) { 1191 pol = NULL; 1192 } else { 1193 pol = ERR_PTR(err); 1194 } 1195 } else 1196 pol = NULL; 1197 } 1198 out: 1199 rcu_read_unlock(); 1200 return pol; 1201 } 1202 1203 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 1204 { 1205 struct net *net = xp_net(pol); 1206 1207 list_add(&pol->walk.all, &net->xfrm.policy_all); 1208 net->xfrm.policy_count[dir]++; 1209 xfrm_pol_hold(pol); 1210 } 1211 1212 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 1213 int dir) 1214 { 1215 struct net *net = xp_net(pol); 1216 1217 if (list_empty(&pol->walk.all)) 1218 return NULL; 1219 1220 /* Socket policies are not hashed. */ 1221 if (!hlist_unhashed(&pol->bydst)) { 1222 hlist_del_rcu(&pol->bydst); 1223 hlist_del(&pol->byidx); 1224 } 1225 1226 list_del_init(&pol->walk.all); 1227 net->xfrm.policy_count[dir]--; 1228 1229 return pol; 1230 } 1231 1232 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 1233 { 1234 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 1235 } 1236 1237 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 1238 { 1239 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 1240 } 1241 1242 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 1243 { 1244 struct net *net = xp_net(pol); 1245 1246 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1247 pol = __xfrm_policy_unlink(pol, dir); 1248 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1249 if (pol) { 1250 xfrm_policy_kill(pol); 1251 return 0; 1252 } 1253 return -ENOENT; 1254 } 1255 EXPORT_SYMBOL(xfrm_policy_delete); 1256 1257 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 1258 { 1259 struct net *net = sock_net(sk); 1260 struct xfrm_policy *old_pol; 1261 1262 #ifdef CONFIG_XFRM_SUB_POLICY 1263 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 1264 return -EINVAL; 1265 #endif 1266 1267 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1268 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 1269 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 1270 if (pol) { 1271 pol->curlft.add_time = get_seconds(); 1272 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 1273 xfrm_sk_policy_link(pol, dir); 1274 } 1275 rcu_assign_pointer(sk->sk_policy[dir], pol); 1276 if (old_pol) { 1277 if (pol) 1278 xfrm_policy_requeue(old_pol, pol); 1279 1280 /* Unlinking succeeds always. This is the only function 1281 * allowed to delete or replace socket policy. 1282 */ 1283 xfrm_sk_policy_unlink(old_pol, dir); 1284 } 1285 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1286 1287 if (old_pol) { 1288 xfrm_policy_kill(old_pol); 1289 } 1290 return 0; 1291 } 1292 1293 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 1294 { 1295 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 1296 struct net *net = xp_net(old); 1297 1298 if (newp) { 1299 newp->selector = old->selector; 1300 if (security_xfrm_policy_clone(old->security, 1301 &newp->security)) { 1302 kfree(newp); 1303 return NULL; /* ENOMEM */ 1304 } 1305 newp->lft = old->lft; 1306 newp->curlft = old->curlft; 1307 newp->mark = old->mark; 1308 newp->action = old->action; 1309 newp->flags = old->flags; 1310 newp->xfrm_nr = old->xfrm_nr; 1311 newp->index = old->index; 1312 newp->type = old->type; 1313 newp->family = old->family; 1314 memcpy(newp->xfrm_vec, old->xfrm_vec, 1315 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 1316 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1317 xfrm_sk_policy_link(newp, dir); 1318 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1319 xfrm_pol_put(newp); 1320 } 1321 return newp; 1322 } 1323 1324 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 1325 { 1326 const struct xfrm_policy *p; 1327 struct xfrm_policy *np; 1328 int i, ret = 0; 1329 1330 rcu_read_lock(); 1331 for (i = 0; i < 2; i++) { 1332 p = rcu_dereference(osk->sk_policy[i]); 1333 if (p) { 1334 np = clone_policy(p, i); 1335 if (unlikely(!np)) { 1336 ret = -ENOMEM; 1337 break; 1338 } 1339 rcu_assign_pointer(sk->sk_policy[i], np); 1340 } 1341 } 1342 rcu_read_unlock(); 1343 return ret; 1344 } 1345 1346 static int 1347 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 1348 xfrm_address_t *remote, unsigned short family, u32 mark) 1349 { 1350 int err; 1351 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1352 1353 if (unlikely(afinfo == NULL)) 1354 return -EINVAL; 1355 err = afinfo->get_saddr(net, oif, local, remote, mark); 1356 rcu_read_unlock(); 1357 return err; 1358 } 1359 1360 /* Resolve list of templates for the flow, given policy. */ 1361 1362 static int 1363 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 1364 struct xfrm_state **xfrm, unsigned short family) 1365 { 1366 struct net *net = xp_net(policy); 1367 int nx; 1368 int i, error; 1369 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 1370 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 1371 xfrm_address_t tmp; 1372 1373 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 1374 struct xfrm_state *x; 1375 xfrm_address_t *remote = daddr; 1376 xfrm_address_t *local = saddr; 1377 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 1378 1379 if (tmpl->mode == XFRM_MODE_TUNNEL || 1380 tmpl->mode == XFRM_MODE_BEET) { 1381 remote = &tmpl->id.daddr; 1382 local = &tmpl->saddr; 1383 if (xfrm_addr_any(local, tmpl->encap_family)) { 1384 error = xfrm_get_saddr(net, fl->flowi_oif, 1385 &tmp, remote, 1386 tmpl->encap_family, 0); 1387 if (error) 1388 goto fail; 1389 local = &tmp; 1390 } 1391 } 1392 1393 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); 1394 1395 if (x && x->km.state == XFRM_STATE_VALID) { 1396 xfrm[nx++] = x; 1397 daddr = remote; 1398 saddr = local; 1399 continue; 1400 } 1401 if (x) { 1402 error = (x->km.state == XFRM_STATE_ERROR ? 1403 -EINVAL : -EAGAIN); 1404 xfrm_state_put(x); 1405 } else if (error == -ESRCH) { 1406 error = -EAGAIN; 1407 } 1408 1409 if (!tmpl->optional) 1410 goto fail; 1411 } 1412 return nx; 1413 1414 fail: 1415 for (nx--; nx >= 0; nx--) 1416 xfrm_state_put(xfrm[nx]); 1417 return error; 1418 } 1419 1420 static int 1421 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 1422 struct xfrm_state **xfrm, unsigned short family) 1423 { 1424 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 1425 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 1426 int cnx = 0; 1427 int error; 1428 int ret; 1429 int i; 1430 1431 for (i = 0; i < npols; i++) { 1432 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 1433 error = -ENOBUFS; 1434 goto fail; 1435 } 1436 1437 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 1438 if (ret < 0) { 1439 error = ret; 1440 goto fail; 1441 } else 1442 cnx += ret; 1443 } 1444 1445 /* found states are sorted for outbound processing */ 1446 if (npols > 1) 1447 xfrm_state_sort(xfrm, tpp, cnx, family); 1448 1449 return cnx; 1450 1451 fail: 1452 for (cnx--; cnx >= 0; cnx--) 1453 xfrm_state_put(tpp[cnx]); 1454 return error; 1455 1456 } 1457 1458 static int xfrm_get_tos(const struct flowi *fl, int family) 1459 { 1460 const struct xfrm_policy_afinfo *afinfo; 1461 int tos; 1462 1463 afinfo = xfrm_policy_get_afinfo(family); 1464 if (!afinfo) 1465 return 0; 1466 1467 tos = afinfo->get_tos(fl); 1468 1469 rcu_read_unlock(); 1470 1471 return tos; 1472 } 1473 1474 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 1475 { 1476 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1477 struct dst_ops *dst_ops; 1478 struct xfrm_dst *xdst; 1479 1480 if (!afinfo) 1481 return ERR_PTR(-EINVAL); 1482 1483 switch (family) { 1484 case AF_INET: 1485 dst_ops = &net->xfrm.xfrm4_dst_ops; 1486 break; 1487 #if IS_ENABLED(CONFIG_IPV6) 1488 case AF_INET6: 1489 dst_ops = &net->xfrm.xfrm6_dst_ops; 1490 break; 1491 #endif 1492 default: 1493 BUG(); 1494 } 1495 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 1496 1497 if (likely(xdst)) { 1498 struct dst_entry *dst = &xdst->u.dst; 1499 1500 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 1501 } else 1502 xdst = ERR_PTR(-ENOBUFS); 1503 1504 rcu_read_unlock(); 1505 1506 return xdst; 1507 } 1508 1509 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 1510 int nfheader_len) 1511 { 1512 const struct xfrm_policy_afinfo *afinfo = 1513 xfrm_policy_get_afinfo(dst->ops->family); 1514 int err; 1515 1516 if (!afinfo) 1517 return -EINVAL; 1518 1519 err = afinfo->init_path(path, dst, nfheader_len); 1520 1521 rcu_read_unlock(); 1522 1523 return err; 1524 } 1525 1526 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 1527 const struct flowi *fl) 1528 { 1529 const struct xfrm_policy_afinfo *afinfo = 1530 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 1531 int err; 1532 1533 if (!afinfo) 1534 return -EINVAL; 1535 1536 err = afinfo->fill_dst(xdst, dev, fl); 1537 1538 rcu_read_unlock(); 1539 1540 return err; 1541 } 1542 1543 1544 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 1545 * all the metrics... Shortly, bundle a bundle. 1546 */ 1547 1548 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 1549 struct xfrm_state **xfrm, 1550 struct xfrm_dst **bundle, 1551 int nx, 1552 const struct flowi *fl, 1553 struct dst_entry *dst) 1554 { 1555 struct net *net = xp_net(policy); 1556 unsigned long now = jiffies; 1557 struct net_device *dev; 1558 struct xfrm_mode *inner_mode; 1559 struct xfrm_dst *xdst_prev = NULL; 1560 struct xfrm_dst *xdst0 = NULL; 1561 int i = 0; 1562 int err; 1563 int header_len = 0; 1564 int nfheader_len = 0; 1565 int trailer_len = 0; 1566 int tos; 1567 int family = policy->selector.family; 1568 xfrm_address_t saddr, daddr; 1569 1570 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 1571 1572 tos = xfrm_get_tos(fl, family); 1573 1574 dst_hold(dst); 1575 1576 for (; i < nx; i++) { 1577 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 1578 struct dst_entry *dst1 = &xdst->u.dst; 1579 1580 err = PTR_ERR(xdst); 1581 if (IS_ERR(xdst)) { 1582 dst_release(dst); 1583 goto put_states; 1584 } 1585 1586 bundle[i] = xdst; 1587 if (!xdst_prev) 1588 xdst0 = xdst; 1589 else 1590 /* Ref count is taken during xfrm_alloc_dst() 1591 * No need to do dst_clone() on dst1 1592 */ 1593 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 1594 1595 if (xfrm[i]->sel.family == AF_UNSPEC) { 1596 inner_mode = xfrm_ip2inner_mode(xfrm[i], 1597 xfrm_af2proto(family)); 1598 if (!inner_mode) { 1599 err = -EAFNOSUPPORT; 1600 dst_release(dst); 1601 goto put_states; 1602 } 1603 } else 1604 inner_mode = xfrm[i]->inner_mode; 1605 1606 xdst->route = dst; 1607 dst_copy_metrics(dst1, dst); 1608 1609 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 1610 family = xfrm[i]->props.family; 1611 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 1612 &saddr, &daddr, family, 1613 xfrm[i]->props.output_mark); 1614 err = PTR_ERR(dst); 1615 if (IS_ERR(dst)) 1616 goto put_states; 1617 } else 1618 dst_hold(dst); 1619 1620 dst1->xfrm = xfrm[i]; 1621 xdst->xfrm_genid = xfrm[i]->genid; 1622 1623 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1624 dst1->flags |= DST_HOST; 1625 dst1->lastuse = now; 1626 1627 dst1->input = dst_discard; 1628 dst1->output = inner_mode->afinfo->output; 1629 1630 xdst_prev = xdst; 1631 1632 header_len += xfrm[i]->props.header_len; 1633 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 1634 nfheader_len += xfrm[i]->props.header_len; 1635 trailer_len += xfrm[i]->props.trailer_len; 1636 } 1637 1638 xfrm_dst_set_child(xdst_prev, dst); 1639 xdst0->path = dst; 1640 1641 err = -ENODEV; 1642 dev = dst->dev; 1643 if (!dev) 1644 goto free_dst; 1645 1646 xfrm_init_path(xdst0, dst, nfheader_len); 1647 xfrm_init_pmtu(bundle, nx); 1648 1649 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 1650 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 1651 err = xfrm_fill_dst(xdst_prev, dev, fl); 1652 if (err) 1653 goto free_dst; 1654 1655 xdst_prev->u.dst.header_len = header_len; 1656 xdst_prev->u.dst.trailer_len = trailer_len; 1657 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 1658 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 1659 } 1660 1661 out: 1662 return &xdst0->u.dst; 1663 1664 put_states: 1665 for (; i < nx; i++) 1666 xfrm_state_put(xfrm[i]); 1667 free_dst: 1668 if (xdst0) 1669 dst_release_immediate(&xdst0->u.dst); 1670 xdst0 = ERR_PTR(err); 1671 goto out; 1672 } 1673 1674 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 1675 struct xfrm_policy **pols, 1676 int *num_pols, int *num_xfrms) 1677 { 1678 int i; 1679 1680 if (*num_pols == 0 || !pols[0]) { 1681 *num_pols = 0; 1682 *num_xfrms = 0; 1683 return 0; 1684 } 1685 if (IS_ERR(pols[0])) 1686 return PTR_ERR(pols[0]); 1687 1688 *num_xfrms = pols[0]->xfrm_nr; 1689 1690 #ifdef CONFIG_XFRM_SUB_POLICY 1691 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 1692 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 1693 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 1694 XFRM_POLICY_TYPE_MAIN, 1695 fl, family, 1696 XFRM_POLICY_OUT); 1697 if (pols[1]) { 1698 if (IS_ERR(pols[1])) { 1699 xfrm_pols_put(pols, *num_pols); 1700 return PTR_ERR(pols[1]); 1701 } 1702 (*num_pols)++; 1703 (*num_xfrms) += pols[1]->xfrm_nr; 1704 } 1705 } 1706 #endif 1707 for (i = 0; i < *num_pols; i++) { 1708 if (pols[i]->action != XFRM_POLICY_ALLOW) { 1709 *num_xfrms = -1; 1710 break; 1711 } 1712 } 1713 1714 return 0; 1715 1716 } 1717 1718 static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old) 1719 { 1720 this_cpu_write(xfrm_last_dst, xdst); 1721 if (old) 1722 dst_release(&old->u.dst); 1723 } 1724 1725 static void __xfrm_pcpu_work_fn(void) 1726 { 1727 struct xfrm_dst *old; 1728 1729 old = this_cpu_read(xfrm_last_dst); 1730 if (old && !xfrm_bundle_ok(old)) 1731 xfrm_last_dst_update(NULL, old); 1732 } 1733 1734 static void xfrm_pcpu_work_fn(struct work_struct *work) 1735 { 1736 local_bh_disable(); 1737 rcu_read_lock(); 1738 __xfrm_pcpu_work_fn(); 1739 rcu_read_unlock(); 1740 local_bh_enable(); 1741 } 1742 1743 void xfrm_policy_cache_flush(void) 1744 { 1745 struct xfrm_dst *old; 1746 bool found = false; 1747 int cpu; 1748 1749 might_sleep(); 1750 1751 local_bh_disable(); 1752 rcu_read_lock(); 1753 for_each_possible_cpu(cpu) { 1754 old = per_cpu(xfrm_last_dst, cpu); 1755 if (old && !xfrm_bundle_ok(old)) { 1756 if (smp_processor_id() == cpu) { 1757 __xfrm_pcpu_work_fn(); 1758 continue; 1759 } 1760 found = true; 1761 break; 1762 } 1763 } 1764 1765 rcu_read_unlock(); 1766 local_bh_enable(); 1767 1768 if (!found) 1769 return; 1770 1771 get_online_cpus(); 1772 1773 for_each_possible_cpu(cpu) { 1774 bool bundle_release; 1775 1776 rcu_read_lock(); 1777 old = per_cpu(xfrm_last_dst, cpu); 1778 bundle_release = old && !xfrm_bundle_ok(old); 1779 rcu_read_unlock(); 1780 1781 if (!bundle_release) 1782 continue; 1783 1784 if (cpu_online(cpu)) { 1785 schedule_work_on(cpu, &xfrm_pcpu_work[cpu]); 1786 continue; 1787 } 1788 1789 rcu_read_lock(); 1790 old = per_cpu(xfrm_last_dst, cpu); 1791 if (old && !xfrm_bundle_ok(old)) { 1792 per_cpu(xfrm_last_dst, cpu) = NULL; 1793 dst_release(&old->u.dst); 1794 } 1795 rcu_read_unlock(); 1796 } 1797 1798 put_online_cpus(); 1799 } 1800 1801 static bool xfrm_xdst_can_reuse(struct xfrm_dst *xdst, 1802 struct xfrm_state * const xfrm[], 1803 int num) 1804 { 1805 const struct dst_entry *dst = &xdst->u.dst; 1806 int i; 1807 1808 if (xdst->num_xfrms != num) 1809 return false; 1810 1811 for (i = 0; i < num; i++) { 1812 if (!dst || dst->xfrm != xfrm[i]) 1813 return false; 1814 dst = xfrm_dst_child(dst); 1815 } 1816 1817 return xfrm_bundle_ok(xdst); 1818 } 1819 1820 static struct xfrm_dst * 1821 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 1822 const struct flowi *fl, u16 family, 1823 struct dst_entry *dst_orig) 1824 { 1825 struct net *net = xp_net(pols[0]); 1826 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 1827 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 1828 struct xfrm_dst *xdst, *old; 1829 struct dst_entry *dst; 1830 int err; 1831 1832 /* Try to instantiate a bundle */ 1833 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 1834 if (err <= 0) { 1835 if (err != 0 && err != -EAGAIN) 1836 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 1837 return ERR_PTR(err); 1838 } 1839 1840 xdst = this_cpu_read(xfrm_last_dst); 1841 if (xdst && 1842 xdst->u.dst.dev == dst_orig->dev && 1843 xdst->num_pols == num_pols && 1844 memcmp(xdst->pols, pols, 1845 sizeof(struct xfrm_policy *) * num_pols) == 0 && 1846 xfrm_xdst_can_reuse(xdst, xfrm, err)) { 1847 dst_hold(&xdst->u.dst); 1848 xfrm_pols_put(pols, num_pols); 1849 while (err > 0) 1850 xfrm_state_put(xfrm[--err]); 1851 return xdst; 1852 } 1853 1854 old = xdst; 1855 1856 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 1857 if (IS_ERR(dst)) { 1858 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 1859 return ERR_CAST(dst); 1860 } 1861 1862 xdst = (struct xfrm_dst *)dst; 1863 xdst->num_xfrms = err; 1864 xdst->num_pols = num_pols; 1865 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 1866 xdst->policy_genid = atomic_read(&pols[0]->genid); 1867 1868 atomic_set(&xdst->u.dst.__refcnt, 2); 1869 xfrm_last_dst_update(xdst, old); 1870 1871 return xdst; 1872 } 1873 1874 static void xfrm_policy_queue_process(struct timer_list *t) 1875 { 1876 struct sk_buff *skb; 1877 struct sock *sk; 1878 struct dst_entry *dst; 1879 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 1880 struct net *net = xp_net(pol); 1881 struct xfrm_policy_queue *pq = &pol->polq; 1882 struct flowi fl; 1883 struct sk_buff_head list; 1884 1885 spin_lock(&pq->hold_queue.lock); 1886 skb = skb_peek(&pq->hold_queue); 1887 if (!skb) { 1888 spin_unlock(&pq->hold_queue.lock); 1889 goto out; 1890 } 1891 dst = skb_dst(skb); 1892 sk = skb->sk; 1893 xfrm_decode_session(skb, &fl, dst->ops->family); 1894 spin_unlock(&pq->hold_queue.lock); 1895 1896 dst_hold(xfrm_dst_path(dst)); 1897 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 1898 if (IS_ERR(dst)) 1899 goto purge_queue; 1900 1901 if (dst->flags & DST_XFRM_QUEUE) { 1902 dst_release(dst); 1903 1904 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 1905 goto purge_queue; 1906 1907 pq->timeout = pq->timeout << 1; 1908 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 1909 xfrm_pol_hold(pol); 1910 goto out; 1911 } 1912 1913 dst_release(dst); 1914 1915 __skb_queue_head_init(&list); 1916 1917 spin_lock(&pq->hold_queue.lock); 1918 pq->timeout = 0; 1919 skb_queue_splice_init(&pq->hold_queue, &list); 1920 spin_unlock(&pq->hold_queue.lock); 1921 1922 while (!skb_queue_empty(&list)) { 1923 skb = __skb_dequeue(&list); 1924 1925 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 1926 dst_hold(xfrm_dst_path(skb_dst(skb))); 1927 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 1928 if (IS_ERR(dst)) { 1929 kfree_skb(skb); 1930 continue; 1931 } 1932 1933 nf_reset(skb); 1934 skb_dst_drop(skb); 1935 skb_dst_set(skb, dst); 1936 1937 dst_output(net, skb->sk, skb); 1938 } 1939 1940 out: 1941 xfrm_pol_put(pol); 1942 return; 1943 1944 purge_queue: 1945 pq->timeout = 0; 1946 skb_queue_purge(&pq->hold_queue); 1947 xfrm_pol_put(pol); 1948 } 1949 1950 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 1951 { 1952 unsigned long sched_next; 1953 struct dst_entry *dst = skb_dst(skb); 1954 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 1955 struct xfrm_policy *pol = xdst->pols[0]; 1956 struct xfrm_policy_queue *pq = &pol->polq; 1957 1958 if (unlikely(skb_fclone_busy(sk, skb))) { 1959 kfree_skb(skb); 1960 return 0; 1961 } 1962 1963 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 1964 kfree_skb(skb); 1965 return -EAGAIN; 1966 } 1967 1968 skb_dst_force(skb); 1969 1970 spin_lock_bh(&pq->hold_queue.lock); 1971 1972 if (!pq->timeout) 1973 pq->timeout = XFRM_QUEUE_TMO_MIN; 1974 1975 sched_next = jiffies + pq->timeout; 1976 1977 if (del_timer(&pq->hold_timer)) { 1978 if (time_before(pq->hold_timer.expires, sched_next)) 1979 sched_next = pq->hold_timer.expires; 1980 xfrm_pol_put(pol); 1981 } 1982 1983 __skb_queue_tail(&pq->hold_queue, skb); 1984 if (!mod_timer(&pq->hold_timer, sched_next)) 1985 xfrm_pol_hold(pol); 1986 1987 spin_unlock_bh(&pq->hold_queue.lock); 1988 1989 return 0; 1990 } 1991 1992 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 1993 struct xfrm_flo *xflo, 1994 const struct flowi *fl, 1995 int num_xfrms, 1996 u16 family) 1997 { 1998 int err; 1999 struct net_device *dev; 2000 struct dst_entry *dst; 2001 struct dst_entry *dst1; 2002 struct xfrm_dst *xdst; 2003 2004 xdst = xfrm_alloc_dst(net, family); 2005 if (IS_ERR(xdst)) 2006 return xdst; 2007 2008 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2009 net->xfrm.sysctl_larval_drop || 2010 num_xfrms <= 0) 2011 return xdst; 2012 2013 dst = xflo->dst_orig; 2014 dst1 = &xdst->u.dst; 2015 dst_hold(dst); 2016 xdst->route = dst; 2017 2018 dst_copy_metrics(dst1, dst); 2019 2020 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2021 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2022 dst1->lastuse = jiffies; 2023 2024 dst1->input = dst_discard; 2025 dst1->output = xdst_queue_output; 2026 2027 dst_hold(dst); 2028 xfrm_dst_set_child(xdst, dst); 2029 xdst->path = dst; 2030 2031 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2032 2033 err = -ENODEV; 2034 dev = dst->dev; 2035 if (!dev) 2036 goto free_dst; 2037 2038 err = xfrm_fill_dst(xdst, dev, fl); 2039 if (err) 2040 goto free_dst; 2041 2042 out: 2043 return xdst; 2044 2045 free_dst: 2046 dst_release(dst1); 2047 xdst = ERR_PTR(err); 2048 goto out; 2049 } 2050 2051 static struct xfrm_dst * 2052 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo) 2053 { 2054 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2055 int num_pols = 0, num_xfrms = 0, err; 2056 struct xfrm_dst *xdst; 2057 2058 /* Resolve policies to use if we couldn't get them from 2059 * previous cache entry */ 2060 num_pols = 1; 2061 pols[0] = xfrm_policy_lookup(net, fl, family, dir); 2062 err = xfrm_expand_policies(fl, family, pols, 2063 &num_pols, &num_xfrms); 2064 if (err < 0) 2065 goto inc_error; 2066 if (num_pols == 0) 2067 return NULL; 2068 if (num_xfrms <= 0) 2069 goto make_dummy_bundle; 2070 2071 local_bh_disable(); 2072 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2073 xflo->dst_orig); 2074 local_bh_enable(); 2075 2076 if (IS_ERR(xdst)) { 2077 err = PTR_ERR(xdst); 2078 if (err != -EAGAIN) 2079 goto error; 2080 goto make_dummy_bundle; 2081 } else if (xdst == NULL) { 2082 num_xfrms = 0; 2083 goto make_dummy_bundle; 2084 } 2085 2086 return xdst; 2087 2088 make_dummy_bundle: 2089 /* We found policies, but there's no bundles to instantiate: 2090 * either because the policy blocks, has no transformations or 2091 * we could not build template (no xfrm_states).*/ 2092 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2093 if (IS_ERR(xdst)) { 2094 xfrm_pols_put(pols, num_pols); 2095 return ERR_CAST(xdst); 2096 } 2097 xdst->num_pols = num_pols; 2098 xdst->num_xfrms = num_xfrms; 2099 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2100 2101 return xdst; 2102 2103 inc_error: 2104 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2105 error: 2106 xfrm_pols_put(pols, num_pols); 2107 return ERR_PTR(err); 2108 } 2109 2110 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2111 struct dst_entry *dst_orig) 2112 { 2113 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2114 struct dst_entry *ret; 2115 2116 if (!afinfo) { 2117 dst_release(dst_orig); 2118 return ERR_PTR(-EINVAL); 2119 } else { 2120 ret = afinfo->blackhole_route(net, dst_orig); 2121 } 2122 rcu_read_unlock(); 2123 2124 return ret; 2125 } 2126 2127 /* Main function: finds/creates a bundle for given flow. 2128 * 2129 * At the moment we eat a raw IP route. Mostly to speed up lookups 2130 * on interfaces with disabled IPsec. 2131 */ 2132 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 2133 const struct flowi *fl, 2134 const struct sock *sk, int flags) 2135 { 2136 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2137 struct xfrm_dst *xdst; 2138 struct dst_entry *dst, *route; 2139 u16 family = dst_orig->ops->family; 2140 u8 dir = XFRM_POLICY_OUT; 2141 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 2142 2143 dst = NULL; 2144 xdst = NULL; 2145 route = NULL; 2146 2147 sk = sk_const_to_full_sk(sk); 2148 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 2149 num_pols = 1; 2150 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family); 2151 err = xfrm_expand_policies(fl, family, pols, 2152 &num_pols, &num_xfrms); 2153 if (err < 0) 2154 goto dropdst; 2155 2156 if (num_pols) { 2157 if (num_xfrms <= 0) { 2158 drop_pols = num_pols; 2159 goto no_transform; 2160 } 2161 2162 local_bh_disable(); 2163 xdst = xfrm_resolve_and_create_bundle( 2164 pols, num_pols, fl, 2165 family, dst_orig); 2166 local_bh_enable(); 2167 2168 if (IS_ERR(xdst)) { 2169 xfrm_pols_put(pols, num_pols); 2170 err = PTR_ERR(xdst); 2171 goto dropdst; 2172 } else if (xdst == NULL) { 2173 num_xfrms = 0; 2174 drop_pols = num_pols; 2175 goto no_transform; 2176 } 2177 2178 route = xdst->route; 2179 } 2180 } 2181 2182 if (xdst == NULL) { 2183 struct xfrm_flo xflo; 2184 2185 xflo.dst_orig = dst_orig; 2186 xflo.flags = flags; 2187 2188 /* To accelerate a bit... */ 2189 if ((dst_orig->flags & DST_NOXFRM) || 2190 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 2191 goto nopol; 2192 2193 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo); 2194 if (xdst == NULL) 2195 goto nopol; 2196 if (IS_ERR(xdst)) { 2197 err = PTR_ERR(xdst); 2198 goto dropdst; 2199 } 2200 2201 num_pols = xdst->num_pols; 2202 num_xfrms = xdst->num_xfrms; 2203 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 2204 route = xdst->route; 2205 } 2206 2207 dst = &xdst->u.dst; 2208 if (route == NULL && num_xfrms > 0) { 2209 /* The only case when xfrm_bundle_lookup() returns a 2210 * bundle with null route, is when the template could 2211 * not be resolved. It means policies are there, but 2212 * bundle could not be created, since we don't yet 2213 * have the xfrm_state's. We need to wait for KM to 2214 * negotiate new SA's or bail out with error.*/ 2215 if (net->xfrm.sysctl_larval_drop) { 2216 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2217 err = -EREMOTE; 2218 goto error; 2219 } 2220 2221 err = -EAGAIN; 2222 2223 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2224 goto error; 2225 } 2226 2227 no_transform: 2228 if (num_pols == 0) 2229 goto nopol; 2230 2231 if ((flags & XFRM_LOOKUP_ICMP) && 2232 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 2233 err = -ENOENT; 2234 goto error; 2235 } 2236 2237 for (i = 0; i < num_pols; i++) 2238 pols[i]->curlft.use_time = get_seconds(); 2239 2240 if (num_xfrms < 0) { 2241 /* Prohibit the flow */ 2242 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 2243 err = -EPERM; 2244 goto error; 2245 } else if (num_xfrms > 0) { 2246 /* Flow transformed */ 2247 dst_release(dst_orig); 2248 } else { 2249 /* Flow passes untransformed */ 2250 dst_release(dst); 2251 dst = dst_orig; 2252 } 2253 ok: 2254 xfrm_pols_put(pols, drop_pols); 2255 if (dst && dst->xfrm && 2256 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 2257 dst->flags |= DST_XFRM_TUNNEL; 2258 return dst; 2259 2260 nopol: 2261 if (!(flags & XFRM_LOOKUP_ICMP)) { 2262 dst = dst_orig; 2263 goto ok; 2264 } 2265 err = -ENOENT; 2266 error: 2267 dst_release(dst); 2268 dropdst: 2269 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 2270 dst_release(dst_orig); 2271 xfrm_pols_put(pols, drop_pols); 2272 return ERR_PTR(err); 2273 } 2274 EXPORT_SYMBOL(xfrm_lookup); 2275 2276 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 2277 * Otherwise we may send out blackholed packets. 2278 */ 2279 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 2280 const struct flowi *fl, 2281 const struct sock *sk, int flags) 2282 { 2283 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 2284 flags | XFRM_LOOKUP_QUEUE | 2285 XFRM_LOOKUP_KEEP_DST_REF); 2286 2287 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 2288 return make_blackhole(net, dst_orig->ops->family, dst_orig); 2289 2290 return dst; 2291 } 2292 EXPORT_SYMBOL(xfrm_lookup_route); 2293 2294 static inline int 2295 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 2296 { 2297 struct xfrm_state *x; 2298 2299 if (!skb->sp || idx < 0 || idx >= skb->sp->len) 2300 return 0; 2301 x = skb->sp->xvec[idx]; 2302 if (!x->type->reject) 2303 return 0; 2304 return x->type->reject(x, skb, fl); 2305 } 2306 2307 /* When skb is transformed back to its "native" form, we have to 2308 * check policy restrictions. At the moment we make this in maximally 2309 * stupid way. Shame on me. :-) Of course, connected sockets must 2310 * have policy cached at them. 2311 */ 2312 2313 static inline int 2314 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 2315 unsigned short family) 2316 { 2317 if (xfrm_state_kern(x)) 2318 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 2319 return x->id.proto == tmpl->id.proto && 2320 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 2321 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 2322 x->props.mode == tmpl->mode && 2323 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 2324 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 2325 !(x->props.mode != XFRM_MODE_TRANSPORT && 2326 xfrm_state_addr_cmp(tmpl, x, family)); 2327 } 2328 2329 /* 2330 * 0 or more than 0 is returned when validation is succeeded (either bypass 2331 * because of optional transport mode, or next index of the mathced secpath 2332 * state with the template. 2333 * -1 is returned when no matching template is found. 2334 * Otherwise "-2 - errored_index" is returned. 2335 */ 2336 static inline int 2337 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 2338 unsigned short family) 2339 { 2340 int idx = start; 2341 2342 if (tmpl->optional) { 2343 if (tmpl->mode == XFRM_MODE_TRANSPORT) 2344 return start; 2345 } else 2346 start = -1; 2347 for (; idx < sp->len; idx++) { 2348 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 2349 return ++idx; 2350 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 2351 if (start == -1) 2352 start = -2-idx; 2353 break; 2354 } 2355 } 2356 return start; 2357 } 2358 2359 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 2360 unsigned int family, int reverse) 2361 { 2362 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2363 int err; 2364 2365 if (unlikely(afinfo == NULL)) 2366 return -EAFNOSUPPORT; 2367 2368 afinfo->decode_session(skb, fl, reverse); 2369 err = security_xfrm_decode_session(skb, &fl->flowi_secid); 2370 rcu_read_unlock(); 2371 return err; 2372 } 2373 EXPORT_SYMBOL(__xfrm_decode_session); 2374 2375 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 2376 { 2377 for (; k < sp->len; k++) { 2378 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 2379 *idxp = k; 2380 return 1; 2381 } 2382 } 2383 2384 return 0; 2385 } 2386 2387 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 2388 unsigned short family) 2389 { 2390 struct net *net = dev_net(skb->dev); 2391 struct xfrm_policy *pol; 2392 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2393 int npols = 0; 2394 int xfrm_nr; 2395 int pi; 2396 int reverse; 2397 struct flowi fl; 2398 int xerr_idx = -1; 2399 2400 reverse = dir & ~XFRM_POLICY_MASK; 2401 dir &= XFRM_POLICY_MASK; 2402 2403 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 2404 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 2405 return 0; 2406 } 2407 2408 nf_nat_decode_session(skb, &fl, family); 2409 2410 /* First, check used SA against their selectors. */ 2411 if (skb->sp) { 2412 int i; 2413 2414 for (i = skb->sp->len-1; i >= 0; i--) { 2415 struct xfrm_state *x = skb->sp->xvec[i]; 2416 if (!xfrm_selector_match(&x->sel, &fl, family)) { 2417 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 2418 return 0; 2419 } 2420 } 2421 } 2422 2423 pol = NULL; 2424 sk = sk_to_full_sk(sk); 2425 if (sk && sk->sk_policy[dir]) { 2426 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family); 2427 if (IS_ERR(pol)) { 2428 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2429 return 0; 2430 } 2431 } 2432 2433 if (!pol) 2434 pol = xfrm_policy_lookup(net, &fl, family, dir); 2435 2436 if (IS_ERR(pol)) { 2437 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2438 return 0; 2439 } 2440 2441 if (!pol) { 2442 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) { 2443 xfrm_secpath_reject(xerr_idx, skb, &fl); 2444 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 2445 return 0; 2446 } 2447 return 1; 2448 } 2449 2450 pol->curlft.use_time = get_seconds(); 2451 2452 pols[0] = pol; 2453 npols++; 2454 #ifdef CONFIG_XFRM_SUB_POLICY 2455 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2456 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 2457 &fl, family, 2458 XFRM_POLICY_IN); 2459 if (pols[1]) { 2460 if (IS_ERR(pols[1])) { 2461 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2462 return 0; 2463 } 2464 pols[1]->curlft.use_time = get_seconds(); 2465 npols++; 2466 } 2467 } 2468 #endif 2469 2470 if (pol->action == XFRM_POLICY_ALLOW) { 2471 struct sec_path *sp; 2472 static struct sec_path dummy; 2473 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 2474 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 2475 struct xfrm_tmpl **tpp = tp; 2476 int ti = 0; 2477 int i, k; 2478 2479 if ((sp = skb->sp) == NULL) 2480 sp = &dummy; 2481 2482 for (pi = 0; pi < npols; pi++) { 2483 if (pols[pi] != pol && 2484 pols[pi]->action != XFRM_POLICY_ALLOW) { 2485 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2486 goto reject; 2487 } 2488 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 2489 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 2490 goto reject_error; 2491 } 2492 for (i = 0; i < pols[pi]->xfrm_nr; i++) 2493 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 2494 } 2495 xfrm_nr = ti; 2496 if (npols > 1) { 2497 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 2498 tpp = stp; 2499 } 2500 2501 /* For each tunnel xfrm, find the first matching tmpl. 2502 * For each tmpl before that, find corresponding xfrm. 2503 * Order is _important_. Later we will implement 2504 * some barriers, but at the moment barriers 2505 * are implied between each two transformations. 2506 */ 2507 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 2508 k = xfrm_policy_ok(tpp[i], sp, k, family); 2509 if (k < 0) { 2510 if (k < -1) 2511 /* "-2 - errored_index" returned */ 2512 xerr_idx = -(2+k); 2513 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2514 goto reject; 2515 } 2516 } 2517 2518 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 2519 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2520 goto reject; 2521 } 2522 2523 xfrm_pols_put(pols, npols); 2524 return 1; 2525 } 2526 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2527 2528 reject: 2529 xfrm_secpath_reject(xerr_idx, skb, &fl); 2530 reject_error: 2531 xfrm_pols_put(pols, npols); 2532 return 0; 2533 } 2534 EXPORT_SYMBOL(__xfrm_policy_check); 2535 2536 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 2537 { 2538 struct net *net = dev_net(skb->dev); 2539 struct flowi fl; 2540 struct dst_entry *dst; 2541 int res = 1; 2542 2543 if (xfrm_decode_session(skb, &fl, family) < 0) { 2544 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2545 return 0; 2546 } 2547 2548 skb_dst_force(skb); 2549 2550 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 2551 if (IS_ERR(dst)) { 2552 res = 0; 2553 dst = NULL; 2554 } 2555 skb_dst_set(skb, dst); 2556 return res; 2557 } 2558 EXPORT_SYMBOL(__xfrm_route_forward); 2559 2560 /* Optimize later using cookies and generation ids. */ 2561 2562 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 2563 { 2564 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 2565 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 2566 * get validated by dst_ops->check on every use. We do this 2567 * because when a normal route referenced by an XFRM dst is 2568 * obsoleted we do not go looking around for all parent 2569 * referencing XFRM dsts so that we can invalidate them. It 2570 * is just too much work. Instead we make the checks here on 2571 * every use. For example: 2572 * 2573 * XFRM dst A --> IPv4 dst X 2574 * 2575 * X is the "xdst->route" of A (X is also the "dst->path" of A 2576 * in this example). If X is marked obsolete, "A" will not 2577 * notice. That's what we are validating here via the 2578 * stale_bundle() check. 2579 * 2580 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 2581 * be marked on it. 2582 * This will force stale_bundle() to fail on any xdst bundle with 2583 * this dst linked in it. 2584 */ 2585 if (dst->obsolete < 0 && !stale_bundle(dst)) 2586 return dst; 2587 2588 return NULL; 2589 } 2590 2591 static int stale_bundle(struct dst_entry *dst) 2592 { 2593 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 2594 } 2595 2596 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 2597 { 2598 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 2599 dst->dev = dev_net(dev)->loopback_dev; 2600 dev_hold(dst->dev); 2601 dev_put(dev); 2602 } 2603 } 2604 EXPORT_SYMBOL(xfrm_dst_ifdown); 2605 2606 static void xfrm_link_failure(struct sk_buff *skb) 2607 { 2608 /* Impossible. Such dst must be popped before reaches point of failure. */ 2609 } 2610 2611 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 2612 { 2613 if (dst) { 2614 if (dst->obsolete) { 2615 dst_release(dst); 2616 dst = NULL; 2617 } 2618 } 2619 return dst; 2620 } 2621 2622 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 2623 { 2624 while (nr--) { 2625 struct xfrm_dst *xdst = bundle[nr]; 2626 u32 pmtu, route_mtu_cached; 2627 struct dst_entry *dst; 2628 2629 dst = &xdst->u.dst; 2630 pmtu = dst_mtu(xfrm_dst_child(dst)); 2631 xdst->child_mtu_cached = pmtu; 2632 2633 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 2634 2635 route_mtu_cached = dst_mtu(xdst->route); 2636 xdst->route_mtu_cached = route_mtu_cached; 2637 2638 if (pmtu > route_mtu_cached) 2639 pmtu = route_mtu_cached; 2640 2641 dst_metric_set(dst, RTAX_MTU, pmtu); 2642 } 2643 } 2644 2645 /* Check that the bundle accepts the flow and its components are 2646 * still valid. 2647 */ 2648 2649 static int xfrm_bundle_ok(struct xfrm_dst *first) 2650 { 2651 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2652 struct dst_entry *dst = &first->u.dst; 2653 struct xfrm_dst *xdst; 2654 int start_from, nr; 2655 u32 mtu; 2656 2657 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 2658 (dst->dev && !netif_running(dst->dev))) 2659 return 0; 2660 2661 if (dst->flags & DST_XFRM_QUEUE) 2662 return 1; 2663 2664 start_from = nr = 0; 2665 do { 2666 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2667 2668 if (dst->xfrm->km.state != XFRM_STATE_VALID) 2669 return 0; 2670 if (xdst->xfrm_genid != dst->xfrm->genid) 2671 return 0; 2672 if (xdst->num_pols > 0 && 2673 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 2674 return 0; 2675 2676 bundle[nr++] = xdst; 2677 2678 mtu = dst_mtu(xfrm_dst_child(dst)); 2679 if (xdst->child_mtu_cached != mtu) { 2680 start_from = nr; 2681 xdst->child_mtu_cached = mtu; 2682 } 2683 2684 if (!dst_check(xdst->route, xdst->route_cookie)) 2685 return 0; 2686 mtu = dst_mtu(xdst->route); 2687 if (xdst->route_mtu_cached != mtu) { 2688 start_from = nr; 2689 xdst->route_mtu_cached = mtu; 2690 } 2691 2692 dst = xfrm_dst_child(dst); 2693 } while (dst->xfrm); 2694 2695 if (likely(!start_from)) 2696 return 1; 2697 2698 xdst = bundle[start_from - 1]; 2699 mtu = xdst->child_mtu_cached; 2700 while (start_from--) { 2701 dst = &xdst->u.dst; 2702 2703 mtu = xfrm_state_mtu(dst->xfrm, mtu); 2704 if (mtu > xdst->route_mtu_cached) 2705 mtu = xdst->route_mtu_cached; 2706 dst_metric_set(dst, RTAX_MTU, mtu); 2707 if (!start_from) 2708 break; 2709 2710 xdst = bundle[start_from - 1]; 2711 xdst->child_mtu_cached = mtu; 2712 } 2713 2714 return 1; 2715 } 2716 2717 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 2718 { 2719 return dst_metric_advmss(xfrm_dst_path(dst)); 2720 } 2721 2722 static unsigned int xfrm_mtu(const struct dst_entry *dst) 2723 { 2724 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 2725 2726 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 2727 } 2728 2729 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 2730 const void *daddr) 2731 { 2732 while (dst->xfrm) { 2733 const struct xfrm_state *xfrm = dst->xfrm; 2734 2735 dst = xfrm_dst_child(dst); 2736 2737 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 2738 continue; 2739 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 2740 daddr = xfrm->coaddr; 2741 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 2742 daddr = &xfrm->id.daddr; 2743 } 2744 return daddr; 2745 } 2746 2747 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 2748 struct sk_buff *skb, 2749 const void *daddr) 2750 { 2751 const struct dst_entry *path = xfrm_dst_path(dst); 2752 2753 if (!skb) 2754 daddr = xfrm_get_dst_nexthop(dst, daddr); 2755 return path->ops->neigh_lookup(path, skb, daddr); 2756 } 2757 2758 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 2759 { 2760 const struct dst_entry *path = xfrm_dst_path(dst); 2761 2762 daddr = xfrm_get_dst_nexthop(dst, daddr); 2763 path->ops->confirm_neigh(path, daddr); 2764 } 2765 2766 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 2767 { 2768 int err = 0; 2769 2770 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 2771 return -EAFNOSUPPORT; 2772 2773 spin_lock(&xfrm_policy_afinfo_lock); 2774 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 2775 err = -EEXIST; 2776 else { 2777 struct dst_ops *dst_ops = afinfo->dst_ops; 2778 if (likely(dst_ops->kmem_cachep == NULL)) 2779 dst_ops->kmem_cachep = xfrm_dst_cache; 2780 if (likely(dst_ops->check == NULL)) 2781 dst_ops->check = xfrm_dst_check; 2782 if (likely(dst_ops->default_advmss == NULL)) 2783 dst_ops->default_advmss = xfrm_default_advmss; 2784 if (likely(dst_ops->mtu == NULL)) 2785 dst_ops->mtu = xfrm_mtu; 2786 if (likely(dst_ops->negative_advice == NULL)) 2787 dst_ops->negative_advice = xfrm_negative_advice; 2788 if (likely(dst_ops->link_failure == NULL)) 2789 dst_ops->link_failure = xfrm_link_failure; 2790 if (likely(dst_ops->neigh_lookup == NULL)) 2791 dst_ops->neigh_lookup = xfrm_neigh_lookup; 2792 if (likely(!dst_ops->confirm_neigh)) 2793 dst_ops->confirm_neigh = xfrm_confirm_neigh; 2794 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 2795 } 2796 spin_unlock(&xfrm_policy_afinfo_lock); 2797 2798 return err; 2799 } 2800 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 2801 2802 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 2803 { 2804 struct dst_ops *dst_ops = afinfo->dst_ops; 2805 int i; 2806 2807 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 2808 if (xfrm_policy_afinfo[i] != afinfo) 2809 continue; 2810 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 2811 break; 2812 } 2813 2814 synchronize_rcu(); 2815 2816 dst_ops->kmem_cachep = NULL; 2817 dst_ops->check = NULL; 2818 dst_ops->negative_advice = NULL; 2819 dst_ops->link_failure = NULL; 2820 } 2821 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 2822 2823 #ifdef CONFIG_XFRM_STATISTICS 2824 static int __net_init xfrm_statistics_init(struct net *net) 2825 { 2826 int rv; 2827 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 2828 if (!net->mib.xfrm_statistics) 2829 return -ENOMEM; 2830 rv = xfrm_proc_init(net); 2831 if (rv < 0) 2832 free_percpu(net->mib.xfrm_statistics); 2833 return rv; 2834 } 2835 2836 static void xfrm_statistics_fini(struct net *net) 2837 { 2838 xfrm_proc_fini(net); 2839 free_percpu(net->mib.xfrm_statistics); 2840 } 2841 #else 2842 static int __net_init xfrm_statistics_init(struct net *net) 2843 { 2844 return 0; 2845 } 2846 2847 static void xfrm_statistics_fini(struct net *net) 2848 { 2849 } 2850 #endif 2851 2852 static int __net_init xfrm_policy_init(struct net *net) 2853 { 2854 unsigned int hmask, sz; 2855 int dir; 2856 2857 if (net_eq(net, &init_net)) 2858 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 2859 sizeof(struct xfrm_dst), 2860 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 2861 NULL); 2862 2863 hmask = 8 - 1; 2864 sz = (hmask+1) * sizeof(struct hlist_head); 2865 2866 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 2867 if (!net->xfrm.policy_byidx) 2868 goto out_byidx; 2869 net->xfrm.policy_idx_hmask = hmask; 2870 2871 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2872 struct xfrm_policy_hash *htab; 2873 2874 net->xfrm.policy_count[dir] = 0; 2875 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 2876 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 2877 2878 htab = &net->xfrm.policy_bydst[dir]; 2879 htab->table = xfrm_hash_alloc(sz); 2880 if (!htab->table) 2881 goto out_bydst; 2882 htab->hmask = hmask; 2883 htab->dbits4 = 32; 2884 htab->sbits4 = 32; 2885 htab->dbits6 = 128; 2886 htab->sbits6 = 128; 2887 } 2888 net->xfrm.policy_hthresh.lbits4 = 32; 2889 net->xfrm.policy_hthresh.rbits4 = 32; 2890 net->xfrm.policy_hthresh.lbits6 = 128; 2891 net->xfrm.policy_hthresh.rbits6 = 128; 2892 2893 seqlock_init(&net->xfrm.policy_hthresh.lock); 2894 2895 INIT_LIST_HEAD(&net->xfrm.policy_all); 2896 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 2897 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 2898 return 0; 2899 2900 out_bydst: 2901 for (dir--; dir >= 0; dir--) { 2902 struct xfrm_policy_hash *htab; 2903 2904 htab = &net->xfrm.policy_bydst[dir]; 2905 xfrm_hash_free(htab->table, sz); 2906 } 2907 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2908 out_byidx: 2909 return -ENOMEM; 2910 } 2911 2912 static void xfrm_policy_fini(struct net *net) 2913 { 2914 unsigned int sz; 2915 int dir; 2916 2917 flush_work(&net->xfrm.policy_hash_work); 2918 #ifdef CONFIG_XFRM_SUB_POLICY 2919 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 2920 #endif 2921 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 2922 2923 WARN_ON(!list_empty(&net->xfrm.policy_all)); 2924 2925 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2926 struct xfrm_policy_hash *htab; 2927 2928 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 2929 2930 htab = &net->xfrm.policy_bydst[dir]; 2931 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 2932 WARN_ON(!hlist_empty(htab->table)); 2933 xfrm_hash_free(htab->table, sz); 2934 } 2935 2936 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 2937 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 2938 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2939 } 2940 2941 static int __net_init xfrm_net_init(struct net *net) 2942 { 2943 int rv; 2944 2945 /* Initialize the per-net locks here */ 2946 spin_lock_init(&net->xfrm.xfrm_state_lock); 2947 spin_lock_init(&net->xfrm.xfrm_policy_lock); 2948 mutex_init(&net->xfrm.xfrm_cfg_mutex); 2949 2950 rv = xfrm_statistics_init(net); 2951 if (rv < 0) 2952 goto out_statistics; 2953 rv = xfrm_state_init(net); 2954 if (rv < 0) 2955 goto out_state; 2956 rv = xfrm_policy_init(net); 2957 if (rv < 0) 2958 goto out_policy; 2959 rv = xfrm_sysctl_init(net); 2960 if (rv < 0) 2961 goto out_sysctl; 2962 2963 return 0; 2964 2965 out_sysctl: 2966 xfrm_policy_fini(net); 2967 out_policy: 2968 xfrm_state_fini(net); 2969 out_state: 2970 xfrm_statistics_fini(net); 2971 out_statistics: 2972 return rv; 2973 } 2974 2975 static void __net_exit xfrm_net_exit(struct net *net) 2976 { 2977 xfrm_sysctl_fini(net); 2978 xfrm_policy_fini(net); 2979 xfrm_state_fini(net); 2980 xfrm_statistics_fini(net); 2981 } 2982 2983 static struct pernet_operations __net_initdata xfrm_net_ops = { 2984 .init = xfrm_net_init, 2985 .exit = xfrm_net_exit, 2986 }; 2987 2988 void __init xfrm_init(void) 2989 { 2990 int i; 2991 2992 xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work), 2993 GFP_KERNEL); 2994 BUG_ON(!xfrm_pcpu_work); 2995 2996 for (i = 0; i < NR_CPUS; i++) 2997 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn); 2998 2999 register_pernet_subsys(&xfrm_net_ops); 3000 xfrm_dev_init(); 3001 seqcount_init(&xfrm_policy_hash_generation); 3002 xfrm_input_init(); 3003 } 3004 3005 #ifdef CONFIG_AUDITSYSCALL 3006 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 3007 struct audit_buffer *audit_buf) 3008 { 3009 struct xfrm_sec_ctx *ctx = xp->security; 3010 struct xfrm_selector *sel = &xp->selector; 3011 3012 if (ctx) 3013 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 3014 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 3015 3016 switch (sel->family) { 3017 case AF_INET: 3018 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 3019 if (sel->prefixlen_s != 32) 3020 audit_log_format(audit_buf, " src_prefixlen=%d", 3021 sel->prefixlen_s); 3022 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 3023 if (sel->prefixlen_d != 32) 3024 audit_log_format(audit_buf, " dst_prefixlen=%d", 3025 sel->prefixlen_d); 3026 break; 3027 case AF_INET6: 3028 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 3029 if (sel->prefixlen_s != 128) 3030 audit_log_format(audit_buf, " src_prefixlen=%d", 3031 sel->prefixlen_s); 3032 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 3033 if (sel->prefixlen_d != 128) 3034 audit_log_format(audit_buf, " dst_prefixlen=%d", 3035 sel->prefixlen_d); 3036 break; 3037 } 3038 } 3039 3040 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 3041 { 3042 struct audit_buffer *audit_buf; 3043 3044 audit_buf = xfrm_audit_start("SPD-add"); 3045 if (audit_buf == NULL) 3046 return; 3047 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3048 audit_log_format(audit_buf, " res=%u", result); 3049 xfrm_audit_common_policyinfo(xp, audit_buf); 3050 audit_log_end(audit_buf); 3051 } 3052 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 3053 3054 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 3055 bool task_valid) 3056 { 3057 struct audit_buffer *audit_buf; 3058 3059 audit_buf = xfrm_audit_start("SPD-delete"); 3060 if (audit_buf == NULL) 3061 return; 3062 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3063 audit_log_format(audit_buf, " res=%u", result); 3064 xfrm_audit_common_policyinfo(xp, audit_buf); 3065 audit_log_end(audit_buf); 3066 } 3067 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 3068 #endif 3069 3070 #ifdef CONFIG_XFRM_MIGRATE 3071 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 3072 const struct xfrm_selector *sel_tgt) 3073 { 3074 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 3075 if (sel_tgt->family == sel_cmp->family && 3076 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 3077 sel_cmp->family) && 3078 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 3079 sel_cmp->family) && 3080 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 3081 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 3082 return true; 3083 } 3084 } else { 3085 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 3086 return true; 3087 } 3088 } 3089 return false; 3090 } 3091 3092 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 3093 u8 dir, u8 type, struct net *net) 3094 { 3095 struct xfrm_policy *pol, *ret = NULL; 3096 struct hlist_head *chain; 3097 u32 priority = ~0U; 3098 3099 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 3100 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 3101 hlist_for_each_entry(pol, chain, bydst) { 3102 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3103 pol->type == type) { 3104 ret = pol; 3105 priority = ret->priority; 3106 break; 3107 } 3108 } 3109 chain = &net->xfrm.policy_inexact[dir]; 3110 hlist_for_each_entry(pol, chain, bydst) { 3111 if ((pol->priority >= priority) && ret) 3112 break; 3113 3114 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3115 pol->type == type) { 3116 ret = pol; 3117 break; 3118 } 3119 } 3120 3121 xfrm_pol_hold(ret); 3122 3123 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 3124 3125 return ret; 3126 } 3127 3128 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 3129 { 3130 int match = 0; 3131 3132 if (t->mode == m->mode && t->id.proto == m->proto && 3133 (m->reqid == 0 || t->reqid == m->reqid)) { 3134 switch (t->mode) { 3135 case XFRM_MODE_TUNNEL: 3136 case XFRM_MODE_BEET: 3137 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 3138 m->old_family) && 3139 xfrm_addr_equal(&t->saddr, &m->old_saddr, 3140 m->old_family)) { 3141 match = 1; 3142 } 3143 break; 3144 case XFRM_MODE_TRANSPORT: 3145 /* in case of transport mode, template does not store 3146 any IP addresses, hence we just compare mode and 3147 protocol */ 3148 match = 1; 3149 break; 3150 default: 3151 break; 3152 } 3153 } 3154 return match; 3155 } 3156 3157 /* update endpoint address(es) of template(s) */ 3158 static int xfrm_policy_migrate(struct xfrm_policy *pol, 3159 struct xfrm_migrate *m, int num_migrate) 3160 { 3161 struct xfrm_migrate *mp; 3162 int i, j, n = 0; 3163 3164 write_lock_bh(&pol->lock); 3165 if (unlikely(pol->walk.dead)) { 3166 /* target policy has been deleted */ 3167 write_unlock_bh(&pol->lock); 3168 return -ENOENT; 3169 } 3170 3171 for (i = 0; i < pol->xfrm_nr; i++) { 3172 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 3173 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 3174 continue; 3175 n++; 3176 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 3177 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 3178 continue; 3179 /* update endpoints */ 3180 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 3181 sizeof(pol->xfrm_vec[i].id.daddr)); 3182 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 3183 sizeof(pol->xfrm_vec[i].saddr)); 3184 pol->xfrm_vec[i].encap_family = mp->new_family; 3185 /* flush bundles */ 3186 atomic_inc(&pol->genid); 3187 } 3188 } 3189 3190 write_unlock_bh(&pol->lock); 3191 3192 if (!n) 3193 return -ENODATA; 3194 3195 return 0; 3196 } 3197 3198 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 3199 { 3200 int i, j; 3201 3202 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 3203 return -EINVAL; 3204 3205 for (i = 0; i < num_migrate; i++) { 3206 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 3207 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 3208 return -EINVAL; 3209 3210 /* check if there is any duplicated entry */ 3211 for (j = i + 1; j < num_migrate; j++) { 3212 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 3213 sizeof(m[i].old_daddr)) && 3214 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 3215 sizeof(m[i].old_saddr)) && 3216 m[i].proto == m[j].proto && 3217 m[i].mode == m[j].mode && 3218 m[i].reqid == m[j].reqid && 3219 m[i].old_family == m[j].old_family) 3220 return -EINVAL; 3221 } 3222 } 3223 3224 return 0; 3225 } 3226 3227 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 3228 struct xfrm_migrate *m, int num_migrate, 3229 struct xfrm_kmaddress *k, struct net *net, 3230 struct xfrm_encap_tmpl *encap) 3231 { 3232 int i, err, nx_cur = 0, nx_new = 0; 3233 struct xfrm_policy *pol = NULL; 3234 struct xfrm_state *x, *xc; 3235 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 3236 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 3237 struct xfrm_migrate *mp; 3238 3239 /* Stage 0 - sanity checks */ 3240 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 3241 goto out; 3242 3243 if (dir >= XFRM_POLICY_MAX) { 3244 err = -EINVAL; 3245 goto out; 3246 } 3247 3248 /* Stage 1 - find policy */ 3249 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 3250 err = -ENOENT; 3251 goto out; 3252 } 3253 3254 /* Stage 2 - find and update state(s) */ 3255 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 3256 if ((x = xfrm_migrate_state_find(mp, net))) { 3257 x_cur[nx_cur] = x; 3258 nx_cur++; 3259 xc = xfrm_state_migrate(x, mp, encap); 3260 if (xc) { 3261 x_new[nx_new] = xc; 3262 nx_new++; 3263 } else { 3264 err = -ENODATA; 3265 goto restore_state; 3266 } 3267 } 3268 } 3269 3270 /* Stage 3 - update policy */ 3271 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 3272 goto restore_state; 3273 3274 /* Stage 4 - delete old state(s) */ 3275 if (nx_cur) { 3276 xfrm_states_put(x_cur, nx_cur); 3277 xfrm_states_delete(x_cur, nx_cur); 3278 } 3279 3280 /* Stage 5 - announce */ 3281 km_migrate(sel, dir, type, m, num_migrate, k, encap); 3282 3283 xfrm_pol_put(pol); 3284 3285 return 0; 3286 out: 3287 return err; 3288 3289 restore_state: 3290 if (pol) 3291 xfrm_pol_put(pol); 3292 if (nx_cur) 3293 xfrm_states_put(x_cur, nx_cur); 3294 if (nx_new) 3295 xfrm_states_delete(x_new, nx_new); 3296 3297 return err; 3298 } 3299 EXPORT_SYMBOL(xfrm_migrate); 3300 #endif 3301