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 __read_mostly; 55 static __read_mostly seqcount_t xfrm_policy_hash_generation; 56 57 static void xfrm_init_pmtu(struct dst_entry *dst); 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(unsigned long arg); 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(unsigned long data) 183 { 184 struct xfrm_policy *xp = (struct xfrm_policy *)data; 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 setup_timer(&policy->timer, xfrm_policy_timer, 271 (unsigned long)policy); 272 setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process, 273 (unsigned long)policy); 274 } 275 return policy; 276 } 277 EXPORT_SYMBOL(xfrm_policy_alloc); 278 279 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 280 { 281 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 282 283 security_xfrm_policy_free(policy->security); 284 kfree(policy); 285 } 286 287 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 288 289 void xfrm_policy_destroy(struct xfrm_policy *policy) 290 { 291 BUG_ON(!policy->walk.dead); 292 293 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 294 BUG(); 295 296 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 297 } 298 EXPORT_SYMBOL(xfrm_policy_destroy); 299 300 /* Rule must be locked. Release descendant resources, announce 301 * entry dead. The rule must be unlinked from lists to the moment. 302 */ 303 304 static void xfrm_policy_kill(struct xfrm_policy *policy) 305 { 306 policy->walk.dead = 1; 307 308 atomic_inc(&policy->genid); 309 310 if (del_timer(&policy->polq.hold_timer)) 311 xfrm_pol_put(policy); 312 skb_queue_purge(&policy->polq.hold_queue); 313 314 if (del_timer(&policy->timer)) 315 xfrm_pol_put(policy); 316 317 xfrm_pol_put(policy); 318 } 319 320 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 321 322 static inline unsigned int idx_hash(struct net *net, u32 index) 323 { 324 return __idx_hash(index, net->xfrm.policy_idx_hmask); 325 } 326 327 /* calculate policy hash thresholds */ 328 static void __get_hash_thresh(struct net *net, 329 unsigned short family, int dir, 330 u8 *dbits, u8 *sbits) 331 { 332 switch (family) { 333 case AF_INET: 334 *dbits = net->xfrm.policy_bydst[dir].dbits4; 335 *sbits = net->xfrm.policy_bydst[dir].sbits4; 336 break; 337 338 case AF_INET6: 339 *dbits = net->xfrm.policy_bydst[dir].dbits6; 340 *sbits = net->xfrm.policy_bydst[dir].sbits6; 341 break; 342 343 default: 344 *dbits = 0; 345 *sbits = 0; 346 } 347 } 348 349 static struct hlist_head *policy_hash_bysel(struct net *net, 350 const struct xfrm_selector *sel, 351 unsigned short family, int dir) 352 { 353 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 354 unsigned int hash; 355 u8 dbits; 356 u8 sbits; 357 358 __get_hash_thresh(net, family, dir, &dbits, &sbits); 359 hash = __sel_hash(sel, family, hmask, dbits, sbits); 360 361 if (hash == hmask + 1) 362 return &net->xfrm.policy_inexact[dir]; 363 364 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 365 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 366 } 367 368 static struct hlist_head *policy_hash_direct(struct net *net, 369 const xfrm_address_t *daddr, 370 const xfrm_address_t *saddr, 371 unsigned short family, int dir) 372 { 373 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 374 unsigned int hash; 375 u8 dbits; 376 u8 sbits; 377 378 __get_hash_thresh(net, family, dir, &dbits, &sbits); 379 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 380 381 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 382 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 383 } 384 385 static void xfrm_dst_hash_transfer(struct net *net, 386 struct hlist_head *list, 387 struct hlist_head *ndsttable, 388 unsigned int nhashmask, 389 int dir) 390 { 391 struct hlist_node *tmp, *entry0 = NULL; 392 struct xfrm_policy *pol; 393 unsigned int h0 = 0; 394 u8 dbits; 395 u8 sbits; 396 397 redo: 398 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 399 unsigned int h; 400 401 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 402 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 403 pol->family, nhashmask, dbits, sbits); 404 if (!entry0) { 405 hlist_del_rcu(&pol->bydst); 406 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 407 h0 = h; 408 } else { 409 if (h != h0) 410 continue; 411 hlist_del_rcu(&pol->bydst); 412 hlist_add_behind_rcu(&pol->bydst, entry0); 413 } 414 entry0 = &pol->bydst; 415 } 416 if (!hlist_empty(list)) { 417 entry0 = NULL; 418 goto redo; 419 } 420 } 421 422 static void xfrm_idx_hash_transfer(struct hlist_head *list, 423 struct hlist_head *nidxtable, 424 unsigned int nhashmask) 425 { 426 struct hlist_node *tmp; 427 struct xfrm_policy *pol; 428 429 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 430 unsigned int h; 431 432 h = __idx_hash(pol->index, nhashmask); 433 hlist_add_head(&pol->byidx, nidxtable+h); 434 } 435 } 436 437 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 438 { 439 return ((old_hmask + 1) << 1) - 1; 440 } 441 442 static void xfrm_bydst_resize(struct net *net, int dir) 443 { 444 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 445 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 446 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 447 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 448 struct hlist_head *odst; 449 int i; 450 451 if (!ndst) 452 return; 453 454 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 455 write_seqcount_begin(&xfrm_policy_hash_generation); 456 457 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 458 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 459 460 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 461 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 462 463 for (i = hmask; i >= 0; i--) 464 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 465 466 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 467 net->xfrm.policy_bydst[dir].hmask = nhashmask; 468 469 write_seqcount_end(&xfrm_policy_hash_generation); 470 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 471 472 synchronize_rcu(); 473 474 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 475 } 476 477 static void xfrm_byidx_resize(struct net *net, int total) 478 { 479 unsigned int hmask = net->xfrm.policy_idx_hmask; 480 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 481 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 482 struct hlist_head *oidx = net->xfrm.policy_byidx; 483 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 484 int i; 485 486 if (!nidx) 487 return; 488 489 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 490 491 for (i = hmask; i >= 0; i--) 492 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 493 494 net->xfrm.policy_byidx = nidx; 495 net->xfrm.policy_idx_hmask = nhashmask; 496 497 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 498 499 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 500 } 501 502 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 503 { 504 unsigned int cnt = net->xfrm.policy_count[dir]; 505 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 506 507 if (total) 508 *total += cnt; 509 510 if ((hmask + 1) < xfrm_policy_hashmax && 511 cnt > hmask) 512 return 1; 513 514 return 0; 515 } 516 517 static inline int xfrm_byidx_should_resize(struct net *net, int total) 518 { 519 unsigned int hmask = net->xfrm.policy_idx_hmask; 520 521 if ((hmask + 1) < xfrm_policy_hashmax && 522 total > hmask) 523 return 1; 524 525 return 0; 526 } 527 528 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 529 { 530 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 531 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 532 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 533 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 534 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 535 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 536 si->spdhcnt = net->xfrm.policy_idx_hmask; 537 si->spdhmcnt = xfrm_policy_hashmax; 538 } 539 EXPORT_SYMBOL(xfrm_spd_getinfo); 540 541 static DEFINE_MUTEX(hash_resize_mutex); 542 static void xfrm_hash_resize(struct work_struct *work) 543 { 544 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 545 int dir, total; 546 547 mutex_lock(&hash_resize_mutex); 548 549 total = 0; 550 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 551 if (xfrm_bydst_should_resize(net, dir, &total)) 552 xfrm_bydst_resize(net, dir); 553 } 554 if (xfrm_byidx_should_resize(net, total)) 555 xfrm_byidx_resize(net, total); 556 557 mutex_unlock(&hash_resize_mutex); 558 } 559 560 static void xfrm_hash_rebuild(struct work_struct *work) 561 { 562 struct net *net = container_of(work, struct net, 563 xfrm.policy_hthresh.work); 564 unsigned int hmask; 565 struct xfrm_policy *pol; 566 struct xfrm_policy *policy; 567 struct hlist_head *chain; 568 struct hlist_head *odst; 569 struct hlist_node *newpos; 570 int i; 571 int dir; 572 unsigned seq; 573 u8 lbits4, rbits4, lbits6, rbits6; 574 575 mutex_lock(&hash_resize_mutex); 576 577 /* read selector prefixlen thresholds */ 578 do { 579 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 580 581 lbits4 = net->xfrm.policy_hthresh.lbits4; 582 rbits4 = net->xfrm.policy_hthresh.rbits4; 583 lbits6 = net->xfrm.policy_hthresh.lbits6; 584 rbits6 = net->xfrm.policy_hthresh.rbits6; 585 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 586 587 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 588 589 /* reset the bydst and inexact table in all directions */ 590 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 591 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 592 hmask = net->xfrm.policy_bydst[dir].hmask; 593 odst = net->xfrm.policy_bydst[dir].table; 594 for (i = hmask; i >= 0; i--) 595 INIT_HLIST_HEAD(odst + i); 596 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 597 /* dir out => dst = remote, src = local */ 598 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 599 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 600 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 601 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 602 } else { 603 /* dir in/fwd => dst = local, src = remote */ 604 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 605 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 606 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 607 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 608 } 609 } 610 611 /* re-insert all policies by order of creation */ 612 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 613 if (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 else 979 xfrm_policy_cache_flush(); 980 out: 981 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 982 return err; 983 } 984 EXPORT_SYMBOL(xfrm_policy_flush); 985 986 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 987 int (*func)(struct xfrm_policy *, int, int, void*), 988 void *data) 989 { 990 struct xfrm_policy *pol; 991 struct xfrm_policy_walk_entry *x; 992 int error = 0; 993 994 if (walk->type >= XFRM_POLICY_TYPE_MAX && 995 walk->type != XFRM_POLICY_TYPE_ANY) 996 return -EINVAL; 997 998 if (list_empty(&walk->walk.all) && walk->seq != 0) 999 return 0; 1000 1001 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1002 if (list_empty(&walk->walk.all)) 1003 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1004 else 1005 x = list_first_entry(&walk->walk.all, 1006 struct xfrm_policy_walk_entry, all); 1007 1008 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1009 if (x->dead) 1010 continue; 1011 pol = container_of(x, struct xfrm_policy, walk); 1012 if (walk->type != XFRM_POLICY_TYPE_ANY && 1013 walk->type != pol->type) 1014 continue; 1015 error = func(pol, xfrm_policy_id2dir(pol->index), 1016 walk->seq, data); 1017 if (error) { 1018 list_move_tail(&walk->walk.all, &x->all); 1019 goto out; 1020 } 1021 walk->seq++; 1022 } 1023 if (walk->seq == 0) { 1024 error = -ENOENT; 1025 goto out; 1026 } 1027 list_del_init(&walk->walk.all); 1028 out: 1029 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1030 return error; 1031 } 1032 EXPORT_SYMBOL(xfrm_policy_walk); 1033 1034 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1035 { 1036 INIT_LIST_HEAD(&walk->walk.all); 1037 walk->walk.dead = 1; 1038 walk->type = type; 1039 walk->seq = 0; 1040 } 1041 EXPORT_SYMBOL(xfrm_policy_walk_init); 1042 1043 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1044 { 1045 if (list_empty(&walk->walk.all)) 1046 return; 1047 1048 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1049 list_del(&walk->walk.all); 1050 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1051 } 1052 EXPORT_SYMBOL(xfrm_policy_walk_done); 1053 1054 /* 1055 * Find policy to apply to this flow. 1056 * 1057 * Returns 0 if policy found, else an -errno. 1058 */ 1059 static int xfrm_policy_match(const struct xfrm_policy *pol, 1060 const struct flowi *fl, 1061 u8 type, u16 family, int dir) 1062 { 1063 const struct xfrm_selector *sel = &pol->selector; 1064 int ret = -ESRCH; 1065 bool match; 1066 1067 if (pol->family != family || 1068 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1069 pol->type != type) 1070 return ret; 1071 1072 match = xfrm_selector_match(sel, fl, family); 1073 if (match) 1074 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1075 dir); 1076 1077 return ret; 1078 } 1079 1080 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 1081 const struct flowi *fl, 1082 u16 family, u8 dir) 1083 { 1084 int err; 1085 struct xfrm_policy *pol, *ret; 1086 const xfrm_address_t *daddr, *saddr; 1087 struct hlist_head *chain; 1088 unsigned int sequence; 1089 u32 priority; 1090 1091 daddr = xfrm_flowi_daddr(fl, family); 1092 saddr = xfrm_flowi_saddr(fl, family); 1093 if (unlikely(!daddr || !saddr)) 1094 return NULL; 1095 1096 rcu_read_lock(); 1097 retry: 1098 do { 1099 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 1100 chain = policy_hash_direct(net, daddr, saddr, family, dir); 1101 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 1102 1103 priority = ~0U; 1104 ret = NULL; 1105 hlist_for_each_entry_rcu(pol, chain, bydst) { 1106 err = xfrm_policy_match(pol, fl, type, family, dir); 1107 if (err) { 1108 if (err == -ESRCH) 1109 continue; 1110 else { 1111 ret = ERR_PTR(err); 1112 goto fail; 1113 } 1114 } else { 1115 ret = pol; 1116 priority = ret->priority; 1117 break; 1118 } 1119 } 1120 chain = &net->xfrm.policy_inexact[dir]; 1121 hlist_for_each_entry_rcu(pol, chain, bydst) { 1122 if ((pol->priority >= priority) && ret) 1123 break; 1124 1125 err = xfrm_policy_match(pol, fl, type, family, dir); 1126 if (err) { 1127 if (err == -ESRCH) 1128 continue; 1129 else { 1130 ret = ERR_PTR(err); 1131 goto fail; 1132 } 1133 } else { 1134 ret = pol; 1135 break; 1136 } 1137 } 1138 1139 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 1140 goto retry; 1141 1142 if (ret && !xfrm_pol_hold_rcu(ret)) 1143 goto retry; 1144 fail: 1145 rcu_read_unlock(); 1146 1147 return ret; 1148 } 1149 1150 static struct xfrm_policy * 1151 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir) 1152 { 1153 #ifdef CONFIG_XFRM_SUB_POLICY 1154 struct xfrm_policy *pol; 1155 1156 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir); 1157 if (pol != NULL) 1158 return pol; 1159 #endif 1160 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir); 1161 } 1162 1163 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 1164 const struct flowi *fl, u16 family) 1165 { 1166 struct xfrm_policy *pol; 1167 1168 rcu_read_lock(); 1169 again: 1170 pol = rcu_dereference(sk->sk_policy[dir]); 1171 if (pol != NULL) { 1172 bool match = xfrm_selector_match(&pol->selector, fl, family); 1173 int err = 0; 1174 1175 if (match) { 1176 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) { 1177 pol = NULL; 1178 goto out; 1179 } 1180 err = security_xfrm_policy_lookup(pol->security, 1181 fl->flowi_secid, 1182 dir); 1183 if (!err) { 1184 if (!xfrm_pol_hold_rcu(pol)) 1185 goto again; 1186 } else if (err == -ESRCH) { 1187 pol = NULL; 1188 } else { 1189 pol = ERR_PTR(err); 1190 } 1191 } else 1192 pol = NULL; 1193 } 1194 out: 1195 rcu_read_unlock(); 1196 return pol; 1197 } 1198 1199 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 1200 { 1201 struct net *net = xp_net(pol); 1202 1203 list_add(&pol->walk.all, &net->xfrm.policy_all); 1204 net->xfrm.policy_count[dir]++; 1205 xfrm_pol_hold(pol); 1206 } 1207 1208 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 1209 int dir) 1210 { 1211 struct net *net = xp_net(pol); 1212 1213 if (list_empty(&pol->walk.all)) 1214 return NULL; 1215 1216 /* Socket policies are not hashed. */ 1217 if (!hlist_unhashed(&pol->bydst)) { 1218 hlist_del_rcu(&pol->bydst); 1219 hlist_del(&pol->byidx); 1220 } 1221 1222 list_del_init(&pol->walk.all); 1223 net->xfrm.policy_count[dir]--; 1224 1225 return pol; 1226 } 1227 1228 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 1229 { 1230 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 1231 } 1232 1233 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 1234 { 1235 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 1236 } 1237 1238 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 1239 { 1240 struct net *net = xp_net(pol); 1241 1242 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1243 pol = __xfrm_policy_unlink(pol, dir); 1244 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1245 if (pol) { 1246 xfrm_policy_kill(pol); 1247 return 0; 1248 } 1249 return -ENOENT; 1250 } 1251 EXPORT_SYMBOL(xfrm_policy_delete); 1252 1253 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 1254 { 1255 struct net *net = xp_net(pol); 1256 struct xfrm_policy *old_pol; 1257 1258 #ifdef CONFIG_XFRM_SUB_POLICY 1259 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 1260 return -EINVAL; 1261 #endif 1262 1263 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1264 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 1265 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 1266 if (pol) { 1267 pol->curlft.add_time = get_seconds(); 1268 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 1269 xfrm_sk_policy_link(pol, dir); 1270 } 1271 rcu_assign_pointer(sk->sk_policy[dir], pol); 1272 if (old_pol) { 1273 if (pol) 1274 xfrm_policy_requeue(old_pol, pol); 1275 1276 /* Unlinking succeeds always. This is the only function 1277 * allowed to delete or replace socket policy. 1278 */ 1279 xfrm_sk_policy_unlink(old_pol, dir); 1280 } 1281 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1282 1283 if (old_pol) { 1284 xfrm_policy_kill(old_pol); 1285 } 1286 return 0; 1287 } 1288 1289 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 1290 { 1291 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 1292 struct net *net = xp_net(old); 1293 1294 if (newp) { 1295 newp->selector = old->selector; 1296 if (security_xfrm_policy_clone(old->security, 1297 &newp->security)) { 1298 kfree(newp); 1299 return NULL; /* ENOMEM */ 1300 } 1301 newp->lft = old->lft; 1302 newp->curlft = old->curlft; 1303 newp->mark = old->mark; 1304 newp->action = old->action; 1305 newp->flags = old->flags; 1306 newp->xfrm_nr = old->xfrm_nr; 1307 newp->index = old->index; 1308 newp->type = old->type; 1309 memcpy(newp->xfrm_vec, old->xfrm_vec, 1310 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 1311 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1312 xfrm_sk_policy_link(newp, dir); 1313 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1314 xfrm_pol_put(newp); 1315 } 1316 return newp; 1317 } 1318 1319 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 1320 { 1321 const struct xfrm_policy *p; 1322 struct xfrm_policy *np; 1323 int i, ret = 0; 1324 1325 rcu_read_lock(); 1326 for (i = 0; i < 2; i++) { 1327 p = rcu_dereference(osk->sk_policy[i]); 1328 if (p) { 1329 np = clone_policy(p, i); 1330 if (unlikely(!np)) { 1331 ret = -ENOMEM; 1332 break; 1333 } 1334 rcu_assign_pointer(sk->sk_policy[i], np); 1335 } 1336 } 1337 rcu_read_unlock(); 1338 return ret; 1339 } 1340 1341 static int 1342 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 1343 xfrm_address_t *remote, unsigned short family, u32 mark) 1344 { 1345 int err; 1346 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1347 1348 if (unlikely(afinfo == NULL)) 1349 return -EINVAL; 1350 err = afinfo->get_saddr(net, oif, local, remote, mark); 1351 rcu_read_unlock(); 1352 return err; 1353 } 1354 1355 /* Resolve list of templates for the flow, given policy. */ 1356 1357 static int 1358 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 1359 struct xfrm_state **xfrm, unsigned short family) 1360 { 1361 struct net *net = xp_net(policy); 1362 int nx; 1363 int i, error; 1364 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 1365 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 1366 xfrm_address_t tmp; 1367 1368 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 1369 struct xfrm_state *x; 1370 xfrm_address_t *remote = daddr; 1371 xfrm_address_t *local = saddr; 1372 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 1373 1374 if (tmpl->mode == XFRM_MODE_TUNNEL || 1375 tmpl->mode == XFRM_MODE_BEET) { 1376 remote = &tmpl->id.daddr; 1377 local = &tmpl->saddr; 1378 if (xfrm_addr_any(local, tmpl->encap_family)) { 1379 error = xfrm_get_saddr(net, fl->flowi_oif, 1380 &tmp, remote, 1381 tmpl->encap_family, 0); 1382 if (error) 1383 goto fail; 1384 local = &tmp; 1385 } 1386 } 1387 1388 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); 1389 1390 if (x && x->km.state == XFRM_STATE_VALID) { 1391 xfrm[nx++] = x; 1392 daddr = remote; 1393 saddr = local; 1394 continue; 1395 } 1396 if (x) { 1397 error = (x->km.state == XFRM_STATE_ERROR ? 1398 -EINVAL : -EAGAIN); 1399 xfrm_state_put(x); 1400 } else if (error == -ESRCH) { 1401 error = -EAGAIN; 1402 } 1403 1404 if (!tmpl->optional) 1405 goto fail; 1406 } 1407 return nx; 1408 1409 fail: 1410 for (nx--; nx >= 0; nx--) 1411 xfrm_state_put(xfrm[nx]); 1412 return error; 1413 } 1414 1415 static int 1416 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 1417 struct xfrm_state **xfrm, unsigned short family) 1418 { 1419 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 1420 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 1421 int cnx = 0; 1422 int error; 1423 int ret; 1424 int i; 1425 1426 for (i = 0; i < npols; i++) { 1427 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 1428 error = -ENOBUFS; 1429 goto fail; 1430 } 1431 1432 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 1433 if (ret < 0) { 1434 error = ret; 1435 goto fail; 1436 } else 1437 cnx += ret; 1438 } 1439 1440 /* found states are sorted for outbound processing */ 1441 if (npols > 1) 1442 xfrm_state_sort(xfrm, tpp, cnx, family); 1443 1444 return cnx; 1445 1446 fail: 1447 for (cnx--; cnx >= 0; cnx--) 1448 xfrm_state_put(tpp[cnx]); 1449 return error; 1450 1451 } 1452 1453 static int xfrm_get_tos(const struct flowi *fl, int family) 1454 { 1455 const struct xfrm_policy_afinfo *afinfo; 1456 int tos = 0; 1457 1458 afinfo = xfrm_policy_get_afinfo(family); 1459 tos = afinfo ? afinfo->get_tos(fl) : 0; 1460 1461 rcu_read_unlock(); 1462 1463 return tos; 1464 } 1465 1466 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 1467 { 1468 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1469 struct dst_ops *dst_ops; 1470 struct xfrm_dst *xdst; 1471 1472 if (!afinfo) 1473 return ERR_PTR(-EINVAL); 1474 1475 switch (family) { 1476 case AF_INET: 1477 dst_ops = &net->xfrm.xfrm4_dst_ops; 1478 break; 1479 #if IS_ENABLED(CONFIG_IPV6) 1480 case AF_INET6: 1481 dst_ops = &net->xfrm.xfrm6_dst_ops; 1482 break; 1483 #endif 1484 default: 1485 BUG(); 1486 } 1487 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 1488 1489 if (likely(xdst)) { 1490 struct dst_entry *dst = &xdst->u.dst; 1491 1492 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 1493 } else 1494 xdst = ERR_PTR(-ENOBUFS); 1495 1496 rcu_read_unlock(); 1497 1498 return xdst; 1499 } 1500 1501 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 1502 int nfheader_len) 1503 { 1504 const struct xfrm_policy_afinfo *afinfo = 1505 xfrm_policy_get_afinfo(dst->ops->family); 1506 int err; 1507 1508 if (!afinfo) 1509 return -EINVAL; 1510 1511 err = afinfo->init_path(path, dst, nfheader_len); 1512 1513 rcu_read_unlock(); 1514 1515 return err; 1516 } 1517 1518 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 1519 const struct flowi *fl) 1520 { 1521 const struct xfrm_policy_afinfo *afinfo = 1522 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 1523 int err; 1524 1525 if (!afinfo) 1526 return -EINVAL; 1527 1528 err = afinfo->fill_dst(xdst, dev, fl); 1529 1530 rcu_read_unlock(); 1531 1532 return err; 1533 } 1534 1535 1536 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 1537 * all the metrics... Shortly, bundle a bundle. 1538 */ 1539 1540 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 1541 struct xfrm_state **xfrm, int nx, 1542 const struct flowi *fl, 1543 struct dst_entry *dst) 1544 { 1545 struct net *net = xp_net(policy); 1546 unsigned long now = jiffies; 1547 struct net_device *dev; 1548 struct xfrm_mode *inner_mode; 1549 struct dst_entry *dst_prev = NULL; 1550 struct dst_entry *dst0 = NULL; 1551 int i = 0; 1552 int err; 1553 int header_len = 0; 1554 int nfheader_len = 0; 1555 int trailer_len = 0; 1556 int tos; 1557 int family = policy->selector.family; 1558 xfrm_address_t saddr, daddr; 1559 1560 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 1561 1562 tos = xfrm_get_tos(fl, family); 1563 1564 dst_hold(dst); 1565 1566 for (; i < nx; i++) { 1567 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 1568 struct dst_entry *dst1 = &xdst->u.dst; 1569 1570 err = PTR_ERR(xdst); 1571 if (IS_ERR(xdst)) { 1572 dst_release(dst); 1573 goto put_states; 1574 } 1575 1576 if (xfrm[i]->sel.family == AF_UNSPEC) { 1577 inner_mode = xfrm_ip2inner_mode(xfrm[i], 1578 xfrm_af2proto(family)); 1579 if (!inner_mode) { 1580 err = -EAFNOSUPPORT; 1581 dst_release(dst); 1582 goto put_states; 1583 } 1584 } else 1585 inner_mode = xfrm[i]->inner_mode; 1586 1587 if (!dst_prev) 1588 dst0 = dst1; 1589 else 1590 /* Ref count is taken during xfrm_alloc_dst() 1591 * No need to do dst_clone() on dst1 1592 */ 1593 dst_prev->child = dst1; 1594 1595 xdst->route = dst; 1596 dst_copy_metrics(dst1, dst); 1597 1598 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 1599 family = xfrm[i]->props.family; 1600 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 1601 &saddr, &daddr, family, 1602 xfrm[i]->props.output_mark); 1603 err = PTR_ERR(dst); 1604 if (IS_ERR(dst)) 1605 goto put_states; 1606 } else 1607 dst_hold(dst); 1608 1609 dst1->xfrm = xfrm[i]; 1610 xdst->xfrm_genid = xfrm[i]->genid; 1611 1612 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1613 dst1->flags |= DST_HOST; 1614 dst1->lastuse = now; 1615 1616 dst1->input = dst_discard; 1617 dst1->output = inner_mode->afinfo->output; 1618 1619 dst1->next = dst_prev; 1620 dst_prev = dst1; 1621 1622 header_len += xfrm[i]->props.header_len; 1623 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 1624 nfheader_len += xfrm[i]->props.header_len; 1625 trailer_len += xfrm[i]->props.trailer_len; 1626 } 1627 1628 dst_prev->child = dst; 1629 dst0->path = dst; 1630 1631 err = -ENODEV; 1632 dev = dst->dev; 1633 if (!dev) 1634 goto free_dst; 1635 1636 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len); 1637 xfrm_init_pmtu(dst_prev); 1638 1639 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) { 1640 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev; 1641 1642 err = xfrm_fill_dst(xdst, dev, fl); 1643 if (err) 1644 goto free_dst; 1645 1646 dst_prev->header_len = header_len; 1647 dst_prev->trailer_len = trailer_len; 1648 header_len -= xdst->u.dst.xfrm->props.header_len; 1649 trailer_len -= xdst->u.dst.xfrm->props.trailer_len; 1650 } 1651 1652 out: 1653 return dst0; 1654 1655 put_states: 1656 for (; i < nx; i++) 1657 xfrm_state_put(xfrm[i]); 1658 free_dst: 1659 if (dst0) 1660 dst_release_immediate(dst0); 1661 dst0 = ERR_PTR(err); 1662 goto out; 1663 } 1664 1665 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 1666 struct xfrm_policy **pols, 1667 int *num_pols, int *num_xfrms) 1668 { 1669 int i; 1670 1671 if (*num_pols == 0 || !pols[0]) { 1672 *num_pols = 0; 1673 *num_xfrms = 0; 1674 return 0; 1675 } 1676 if (IS_ERR(pols[0])) 1677 return PTR_ERR(pols[0]); 1678 1679 *num_xfrms = pols[0]->xfrm_nr; 1680 1681 #ifdef CONFIG_XFRM_SUB_POLICY 1682 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 1683 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 1684 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 1685 XFRM_POLICY_TYPE_MAIN, 1686 fl, family, 1687 XFRM_POLICY_OUT); 1688 if (pols[1]) { 1689 if (IS_ERR(pols[1])) { 1690 xfrm_pols_put(pols, *num_pols); 1691 return PTR_ERR(pols[1]); 1692 } 1693 (*num_pols)++; 1694 (*num_xfrms) += pols[1]->xfrm_nr; 1695 } 1696 } 1697 #endif 1698 for (i = 0; i < *num_pols; i++) { 1699 if (pols[i]->action != XFRM_POLICY_ALLOW) { 1700 *num_xfrms = -1; 1701 break; 1702 } 1703 } 1704 1705 return 0; 1706 1707 } 1708 1709 static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old) 1710 { 1711 this_cpu_write(xfrm_last_dst, xdst); 1712 if (old) 1713 dst_release(&old->u.dst); 1714 } 1715 1716 static void __xfrm_pcpu_work_fn(void) 1717 { 1718 struct xfrm_dst *old; 1719 1720 old = this_cpu_read(xfrm_last_dst); 1721 if (old && !xfrm_bundle_ok(old)) 1722 xfrm_last_dst_update(NULL, old); 1723 } 1724 1725 static void xfrm_pcpu_work_fn(struct work_struct *work) 1726 { 1727 local_bh_disable(); 1728 rcu_read_lock(); 1729 __xfrm_pcpu_work_fn(); 1730 rcu_read_unlock(); 1731 local_bh_enable(); 1732 } 1733 1734 void xfrm_policy_cache_flush(void) 1735 { 1736 struct xfrm_dst *old; 1737 bool found = 0; 1738 int cpu; 1739 1740 local_bh_disable(); 1741 rcu_read_lock(); 1742 for_each_possible_cpu(cpu) { 1743 old = per_cpu(xfrm_last_dst, cpu); 1744 if (old && !xfrm_bundle_ok(old)) { 1745 if (smp_processor_id() == cpu) { 1746 __xfrm_pcpu_work_fn(); 1747 continue; 1748 } 1749 found = true; 1750 break; 1751 } 1752 } 1753 1754 rcu_read_unlock(); 1755 local_bh_enable(); 1756 1757 if (!found) 1758 return; 1759 1760 get_online_cpus(); 1761 1762 for_each_possible_cpu(cpu) { 1763 bool bundle_release; 1764 1765 rcu_read_lock(); 1766 old = per_cpu(xfrm_last_dst, cpu); 1767 bundle_release = old && !xfrm_bundle_ok(old); 1768 rcu_read_unlock(); 1769 1770 if (!bundle_release) 1771 continue; 1772 1773 if (cpu_online(cpu)) { 1774 schedule_work_on(cpu, &xfrm_pcpu_work[cpu]); 1775 continue; 1776 } 1777 1778 rcu_read_lock(); 1779 old = per_cpu(xfrm_last_dst, cpu); 1780 if (old && !xfrm_bundle_ok(old)) { 1781 per_cpu(xfrm_last_dst, cpu) = NULL; 1782 dst_release(&old->u.dst); 1783 } 1784 rcu_read_unlock(); 1785 } 1786 1787 put_online_cpus(); 1788 } 1789 1790 static bool xfrm_pol_dead(struct xfrm_dst *xdst) 1791 { 1792 unsigned int num_pols = xdst->num_pols; 1793 unsigned int pol_dead = 0, i; 1794 1795 for (i = 0; i < num_pols; i++) 1796 pol_dead |= xdst->pols[i]->walk.dead; 1797 1798 /* Mark DST_OBSOLETE_DEAD to fail the next xfrm_dst_check() */ 1799 if (pol_dead) 1800 xdst->u.dst.obsolete = DST_OBSOLETE_DEAD; 1801 1802 return pol_dead; 1803 } 1804 1805 static struct xfrm_dst * 1806 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 1807 const struct flowi *fl, u16 family, 1808 struct dst_entry *dst_orig) 1809 { 1810 struct net *net = xp_net(pols[0]); 1811 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 1812 struct xfrm_dst *xdst, *old; 1813 struct dst_entry *dst; 1814 int err; 1815 1816 xdst = this_cpu_read(xfrm_last_dst); 1817 if (xdst && 1818 xdst->u.dst.dev == dst_orig->dev && 1819 xdst->num_pols == num_pols && 1820 !xfrm_pol_dead(xdst) && 1821 memcmp(xdst->pols, pols, 1822 sizeof(struct xfrm_policy *) * num_pols) == 0 && 1823 xfrm_bundle_ok(xdst)) { 1824 dst_hold(&xdst->u.dst); 1825 return xdst; 1826 } 1827 1828 old = xdst; 1829 /* Try to instantiate a bundle */ 1830 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 1831 if (err <= 0) { 1832 if (err != 0 && err != -EAGAIN) 1833 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 1834 return ERR_PTR(err); 1835 } 1836 1837 dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig); 1838 if (IS_ERR(dst)) { 1839 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 1840 return ERR_CAST(dst); 1841 } 1842 1843 xdst = (struct xfrm_dst *)dst; 1844 xdst->num_xfrms = err; 1845 xdst->num_pols = num_pols; 1846 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 1847 xdst->policy_genid = atomic_read(&pols[0]->genid); 1848 1849 atomic_set(&xdst->u.dst.__refcnt, 2); 1850 xfrm_last_dst_update(xdst, old); 1851 1852 return xdst; 1853 } 1854 1855 static void xfrm_policy_queue_process(unsigned long arg) 1856 { 1857 struct sk_buff *skb; 1858 struct sock *sk; 1859 struct dst_entry *dst; 1860 struct xfrm_policy *pol = (struct xfrm_policy *)arg; 1861 struct net *net = xp_net(pol); 1862 struct xfrm_policy_queue *pq = &pol->polq; 1863 struct flowi fl; 1864 struct sk_buff_head list; 1865 1866 spin_lock(&pq->hold_queue.lock); 1867 skb = skb_peek(&pq->hold_queue); 1868 if (!skb) { 1869 spin_unlock(&pq->hold_queue.lock); 1870 goto out; 1871 } 1872 dst = skb_dst(skb); 1873 sk = skb->sk; 1874 xfrm_decode_session(skb, &fl, dst->ops->family); 1875 spin_unlock(&pq->hold_queue.lock); 1876 1877 dst_hold(dst->path); 1878 dst = xfrm_lookup(net, dst->path, &fl, sk, 0); 1879 if (IS_ERR(dst)) 1880 goto purge_queue; 1881 1882 if (dst->flags & DST_XFRM_QUEUE) { 1883 dst_release(dst); 1884 1885 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 1886 goto purge_queue; 1887 1888 pq->timeout = pq->timeout << 1; 1889 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 1890 xfrm_pol_hold(pol); 1891 goto out; 1892 } 1893 1894 dst_release(dst); 1895 1896 __skb_queue_head_init(&list); 1897 1898 spin_lock(&pq->hold_queue.lock); 1899 pq->timeout = 0; 1900 skb_queue_splice_init(&pq->hold_queue, &list); 1901 spin_unlock(&pq->hold_queue.lock); 1902 1903 while (!skb_queue_empty(&list)) { 1904 skb = __skb_dequeue(&list); 1905 1906 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 1907 dst_hold(skb_dst(skb)->path); 1908 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0); 1909 if (IS_ERR(dst)) { 1910 kfree_skb(skb); 1911 continue; 1912 } 1913 1914 nf_reset(skb); 1915 skb_dst_drop(skb); 1916 skb_dst_set(skb, dst); 1917 1918 dst_output(net, skb->sk, skb); 1919 } 1920 1921 out: 1922 xfrm_pol_put(pol); 1923 return; 1924 1925 purge_queue: 1926 pq->timeout = 0; 1927 skb_queue_purge(&pq->hold_queue); 1928 xfrm_pol_put(pol); 1929 } 1930 1931 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 1932 { 1933 unsigned long sched_next; 1934 struct dst_entry *dst = skb_dst(skb); 1935 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 1936 struct xfrm_policy *pol = xdst->pols[0]; 1937 struct xfrm_policy_queue *pq = &pol->polq; 1938 1939 if (unlikely(skb_fclone_busy(sk, skb))) { 1940 kfree_skb(skb); 1941 return 0; 1942 } 1943 1944 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 1945 kfree_skb(skb); 1946 return -EAGAIN; 1947 } 1948 1949 skb_dst_force(skb); 1950 1951 spin_lock_bh(&pq->hold_queue.lock); 1952 1953 if (!pq->timeout) 1954 pq->timeout = XFRM_QUEUE_TMO_MIN; 1955 1956 sched_next = jiffies + pq->timeout; 1957 1958 if (del_timer(&pq->hold_timer)) { 1959 if (time_before(pq->hold_timer.expires, sched_next)) 1960 sched_next = pq->hold_timer.expires; 1961 xfrm_pol_put(pol); 1962 } 1963 1964 __skb_queue_tail(&pq->hold_queue, skb); 1965 if (!mod_timer(&pq->hold_timer, sched_next)) 1966 xfrm_pol_hold(pol); 1967 1968 spin_unlock_bh(&pq->hold_queue.lock); 1969 1970 return 0; 1971 } 1972 1973 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 1974 struct xfrm_flo *xflo, 1975 const struct flowi *fl, 1976 int num_xfrms, 1977 u16 family) 1978 { 1979 int err; 1980 struct net_device *dev; 1981 struct dst_entry *dst; 1982 struct dst_entry *dst1; 1983 struct xfrm_dst *xdst; 1984 1985 xdst = xfrm_alloc_dst(net, family); 1986 if (IS_ERR(xdst)) 1987 return xdst; 1988 1989 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 1990 net->xfrm.sysctl_larval_drop || 1991 num_xfrms <= 0) 1992 return xdst; 1993 1994 dst = xflo->dst_orig; 1995 dst1 = &xdst->u.dst; 1996 dst_hold(dst); 1997 xdst->route = dst; 1998 1999 dst_copy_metrics(dst1, dst); 2000 2001 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2002 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2003 dst1->lastuse = jiffies; 2004 2005 dst1->input = dst_discard; 2006 dst1->output = xdst_queue_output; 2007 2008 dst_hold(dst); 2009 dst1->child = dst; 2010 dst1->path = dst; 2011 2012 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2013 2014 err = -ENODEV; 2015 dev = dst->dev; 2016 if (!dev) 2017 goto free_dst; 2018 2019 err = xfrm_fill_dst(xdst, dev, fl); 2020 if (err) 2021 goto free_dst; 2022 2023 out: 2024 return xdst; 2025 2026 free_dst: 2027 dst_release(dst1); 2028 xdst = ERR_PTR(err); 2029 goto out; 2030 } 2031 2032 static struct xfrm_dst * 2033 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo) 2034 { 2035 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2036 int num_pols = 0, num_xfrms = 0, err; 2037 struct xfrm_dst *xdst; 2038 2039 /* Resolve policies to use if we couldn't get them from 2040 * previous cache entry */ 2041 num_pols = 1; 2042 pols[0] = xfrm_policy_lookup(net, fl, family, dir); 2043 err = xfrm_expand_policies(fl, family, pols, 2044 &num_pols, &num_xfrms); 2045 if (err < 0) 2046 goto inc_error; 2047 if (num_pols == 0) 2048 return NULL; 2049 if (num_xfrms <= 0) 2050 goto make_dummy_bundle; 2051 2052 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2053 xflo->dst_orig); 2054 if (IS_ERR(xdst)) { 2055 err = PTR_ERR(xdst); 2056 if (err != -EAGAIN) 2057 goto error; 2058 goto make_dummy_bundle; 2059 } else if (xdst == NULL) { 2060 num_xfrms = 0; 2061 goto make_dummy_bundle; 2062 } 2063 2064 return xdst; 2065 2066 make_dummy_bundle: 2067 /* We found policies, but there's no bundles to instantiate: 2068 * either because the policy blocks, has no transformations or 2069 * we could not build template (no xfrm_states).*/ 2070 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2071 if (IS_ERR(xdst)) { 2072 xfrm_pols_put(pols, num_pols); 2073 return ERR_CAST(xdst); 2074 } 2075 xdst->num_pols = num_pols; 2076 xdst->num_xfrms = num_xfrms; 2077 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2078 2079 dst_hold(&xdst->u.dst); 2080 return xdst; 2081 2082 inc_error: 2083 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2084 error: 2085 xfrm_pols_put(pols, num_pols); 2086 return ERR_PTR(err); 2087 } 2088 2089 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2090 struct dst_entry *dst_orig) 2091 { 2092 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2093 struct dst_entry *ret; 2094 2095 if (!afinfo) { 2096 dst_release(dst_orig); 2097 return ERR_PTR(-EINVAL); 2098 } else { 2099 ret = afinfo->blackhole_route(net, dst_orig); 2100 } 2101 rcu_read_unlock(); 2102 2103 return ret; 2104 } 2105 2106 /* Main function: finds/creates a bundle for given flow. 2107 * 2108 * At the moment we eat a raw IP route. Mostly to speed up lookups 2109 * on interfaces with disabled IPsec. 2110 */ 2111 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 2112 const struct flowi *fl, 2113 const struct sock *sk, int flags) 2114 { 2115 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2116 struct xfrm_dst *xdst; 2117 struct dst_entry *dst, *route; 2118 u16 family = dst_orig->ops->family; 2119 u8 dir = XFRM_POLICY_OUT; 2120 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 2121 2122 dst = NULL; 2123 xdst = NULL; 2124 route = NULL; 2125 2126 sk = sk_const_to_full_sk(sk); 2127 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 2128 num_pols = 1; 2129 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family); 2130 err = xfrm_expand_policies(fl, family, pols, 2131 &num_pols, &num_xfrms); 2132 if (err < 0) 2133 goto dropdst; 2134 2135 if (num_pols) { 2136 if (num_xfrms <= 0) { 2137 drop_pols = num_pols; 2138 goto no_transform; 2139 } 2140 2141 xdst = xfrm_resolve_and_create_bundle( 2142 pols, num_pols, fl, 2143 family, dst_orig); 2144 if (IS_ERR(xdst)) { 2145 xfrm_pols_put(pols, num_pols); 2146 err = PTR_ERR(xdst); 2147 goto dropdst; 2148 } else if (xdst == NULL) { 2149 num_xfrms = 0; 2150 drop_pols = num_pols; 2151 goto no_transform; 2152 } 2153 2154 dst_hold(&xdst->u.dst); 2155 route = xdst->route; 2156 } 2157 } 2158 2159 if (xdst == NULL) { 2160 struct xfrm_flo xflo; 2161 2162 xflo.dst_orig = dst_orig; 2163 xflo.flags = flags; 2164 2165 /* To accelerate a bit... */ 2166 if ((dst_orig->flags & DST_NOXFRM) || 2167 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 2168 goto nopol; 2169 2170 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo); 2171 if (xdst == NULL) 2172 goto nopol; 2173 if (IS_ERR(xdst)) { 2174 err = PTR_ERR(xdst); 2175 goto dropdst; 2176 } 2177 2178 num_pols = xdst->num_pols; 2179 num_xfrms = xdst->num_xfrms; 2180 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 2181 route = xdst->route; 2182 } 2183 2184 dst = &xdst->u.dst; 2185 if (route == NULL && num_xfrms > 0) { 2186 /* The only case when xfrm_bundle_lookup() returns a 2187 * bundle with null route, is when the template could 2188 * not be resolved. It means policies are there, but 2189 * bundle could not be created, since we don't yet 2190 * have the xfrm_state's. We need to wait for KM to 2191 * negotiate new SA's or bail out with error.*/ 2192 if (net->xfrm.sysctl_larval_drop) { 2193 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2194 err = -EREMOTE; 2195 goto error; 2196 } 2197 2198 err = -EAGAIN; 2199 2200 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2201 goto error; 2202 } 2203 2204 no_transform: 2205 if (num_pols == 0) 2206 goto nopol; 2207 2208 if ((flags & XFRM_LOOKUP_ICMP) && 2209 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 2210 err = -ENOENT; 2211 goto error; 2212 } 2213 2214 for (i = 0; i < num_pols; i++) 2215 pols[i]->curlft.use_time = get_seconds(); 2216 2217 if (num_xfrms < 0) { 2218 /* Prohibit the flow */ 2219 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 2220 err = -EPERM; 2221 goto error; 2222 } else if (num_xfrms > 0) { 2223 /* Flow transformed */ 2224 dst_release(dst_orig); 2225 } else { 2226 /* Flow passes untransformed */ 2227 dst_release(dst); 2228 dst = dst_orig; 2229 } 2230 ok: 2231 xfrm_pols_put(pols, drop_pols); 2232 if (dst && dst->xfrm && 2233 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 2234 dst->flags |= DST_XFRM_TUNNEL; 2235 return dst; 2236 2237 nopol: 2238 if (!(flags & XFRM_LOOKUP_ICMP)) { 2239 dst = dst_orig; 2240 goto ok; 2241 } 2242 err = -ENOENT; 2243 error: 2244 dst_release(dst); 2245 dropdst: 2246 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 2247 dst_release(dst_orig); 2248 xfrm_pols_put(pols, drop_pols); 2249 return ERR_PTR(err); 2250 } 2251 EXPORT_SYMBOL(xfrm_lookup); 2252 2253 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 2254 * Otherwise we may send out blackholed packets. 2255 */ 2256 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 2257 const struct flowi *fl, 2258 const struct sock *sk, int flags) 2259 { 2260 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 2261 flags | XFRM_LOOKUP_QUEUE | 2262 XFRM_LOOKUP_KEEP_DST_REF); 2263 2264 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 2265 return make_blackhole(net, dst_orig->ops->family, dst_orig); 2266 2267 return dst; 2268 } 2269 EXPORT_SYMBOL(xfrm_lookup_route); 2270 2271 static inline int 2272 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 2273 { 2274 struct xfrm_state *x; 2275 2276 if (!skb->sp || idx < 0 || idx >= skb->sp->len) 2277 return 0; 2278 x = skb->sp->xvec[idx]; 2279 if (!x->type->reject) 2280 return 0; 2281 return x->type->reject(x, skb, fl); 2282 } 2283 2284 /* When skb is transformed back to its "native" form, we have to 2285 * check policy restrictions. At the moment we make this in maximally 2286 * stupid way. Shame on me. :-) Of course, connected sockets must 2287 * have policy cached at them. 2288 */ 2289 2290 static inline int 2291 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 2292 unsigned short family) 2293 { 2294 if (xfrm_state_kern(x)) 2295 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 2296 return x->id.proto == tmpl->id.proto && 2297 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 2298 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 2299 x->props.mode == tmpl->mode && 2300 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 2301 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 2302 !(x->props.mode != XFRM_MODE_TRANSPORT && 2303 xfrm_state_addr_cmp(tmpl, x, family)); 2304 } 2305 2306 /* 2307 * 0 or more than 0 is returned when validation is succeeded (either bypass 2308 * because of optional transport mode, or next index of the mathced secpath 2309 * state with the template. 2310 * -1 is returned when no matching template is found. 2311 * Otherwise "-2 - errored_index" is returned. 2312 */ 2313 static inline int 2314 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 2315 unsigned short family) 2316 { 2317 int idx = start; 2318 2319 if (tmpl->optional) { 2320 if (tmpl->mode == XFRM_MODE_TRANSPORT) 2321 return start; 2322 } else 2323 start = -1; 2324 for (; idx < sp->len; idx++) { 2325 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 2326 return ++idx; 2327 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 2328 if (start == -1) 2329 start = -2-idx; 2330 break; 2331 } 2332 } 2333 return start; 2334 } 2335 2336 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 2337 unsigned int family, int reverse) 2338 { 2339 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2340 int err; 2341 2342 if (unlikely(afinfo == NULL)) 2343 return -EAFNOSUPPORT; 2344 2345 afinfo->decode_session(skb, fl, reverse); 2346 err = security_xfrm_decode_session(skb, &fl->flowi_secid); 2347 rcu_read_unlock(); 2348 return err; 2349 } 2350 EXPORT_SYMBOL(__xfrm_decode_session); 2351 2352 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 2353 { 2354 for (; k < sp->len; k++) { 2355 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 2356 *idxp = k; 2357 return 1; 2358 } 2359 } 2360 2361 return 0; 2362 } 2363 2364 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 2365 unsigned short family) 2366 { 2367 struct net *net = dev_net(skb->dev); 2368 struct xfrm_policy *pol; 2369 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2370 int npols = 0; 2371 int xfrm_nr; 2372 int pi; 2373 int reverse; 2374 struct flowi fl; 2375 int xerr_idx = -1; 2376 2377 reverse = dir & ~XFRM_POLICY_MASK; 2378 dir &= XFRM_POLICY_MASK; 2379 2380 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 2381 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 2382 return 0; 2383 } 2384 2385 nf_nat_decode_session(skb, &fl, family); 2386 2387 /* First, check used SA against their selectors. */ 2388 if (skb->sp) { 2389 int i; 2390 2391 for (i = skb->sp->len-1; i >= 0; i--) { 2392 struct xfrm_state *x = skb->sp->xvec[i]; 2393 if (!xfrm_selector_match(&x->sel, &fl, family)) { 2394 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 2395 return 0; 2396 } 2397 } 2398 } 2399 2400 pol = NULL; 2401 sk = sk_to_full_sk(sk); 2402 if (sk && sk->sk_policy[dir]) { 2403 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family); 2404 if (IS_ERR(pol)) { 2405 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2406 return 0; 2407 } 2408 } 2409 2410 if (!pol) 2411 pol = xfrm_policy_lookup(net, &fl, family, dir); 2412 2413 if (IS_ERR(pol)) { 2414 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2415 return 0; 2416 } 2417 2418 if (!pol) { 2419 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) { 2420 xfrm_secpath_reject(xerr_idx, skb, &fl); 2421 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 2422 return 0; 2423 } 2424 return 1; 2425 } 2426 2427 pol->curlft.use_time = get_seconds(); 2428 2429 pols[0] = pol; 2430 npols++; 2431 #ifdef CONFIG_XFRM_SUB_POLICY 2432 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2433 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 2434 &fl, family, 2435 XFRM_POLICY_IN); 2436 if (pols[1]) { 2437 if (IS_ERR(pols[1])) { 2438 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2439 return 0; 2440 } 2441 pols[1]->curlft.use_time = get_seconds(); 2442 npols++; 2443 } 2444 } 2445 #endif 2446 2447 if (pol->action == XFRM_POLICY_ALLOW) { 2448 struct sec_path *sp; 2449 static struct sec_path dummy; 2450 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 2451 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 2452 struct xfrm_tmpl **tpp = tp; 2453 int ti = 0; 2454 int i, k; 2455 2456 if ((sp = skb->sp) == NULL) 2457 sp = &dummy; 2458 2459 for (pi = 0; pi < npols; pi++) { 2460 if (pols[pi] != pol && 2461 pols[pi]->action != XFRM_POLICY_ALLOW) { 2462 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2463 goto reject; 2464 } 2465 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 2466 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 2467 goto reject_error; 2468 } 2469 for (i = 0; i < pols[pi]->xfrm_nr; i++) 2470 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 2471 } 2472 xfrm_nr = ti; 2473 if (npols > 1) { 2474 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 2475 tpp = stp; 2476 } 2477 2478 /* For each tunnel xfrm, find the first matching tmpl. 2479 * For each tmpl before that, find corresponding xfrm. 2480 * Order is _important_. Later we will implement 2481 * some barriers, but at the moment barriers 2482 * are implied between each two transformations. 2483 */ 2484 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 2485 k = xfrm_policy_ok(tpp[i], sp, k, family); 2486 if (k < 0) { 2487 if (k < -1) 2488 /* "-2 - errored_index" returned */ 2489 xerr_idx = -(2+k); 2490 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2491 goto reject; 2492 } 2493 } 2494 2495 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 2496 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2497 goto reject; 2498 } 2499 2500 xfrm_pols_put(pols, npols); 2501 return 1; 2502 } 2503 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2504 2505 reject: 2506 xfrm_secpath_reject(xerr_idx, skb, &fl); 2507 reject_error: 2508 xfrm_pols_put(pols, npols); 2509 return 0; 2510 } 2511 EXPORT_SYMBOL(__xfrm_policy_check); 2512 2513 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 2514 { 2515 struct net *net = dev_net(skb->dev); 2516 struct flowi fl; 2517 struct dst_entry *dst; 2518 int res = 1; 2519 2520 if (xfrm_decode_session(skb, &fl, family) < 0) { 2521 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2522 return 0; 2523 } 2524 2525 skb_dst_force(skb); 2526 2527 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 2528 if (IS_ERR(dst)) { 2529 res = 0; 2530 dst = NULL; 2531 } 2532 skb_dst_set(skb, dst); 2533 return res; 2534 } 2535 EXPORT_SYMBOL(__xfrm_route_forward); 2536 2537 /* Optimize later using cookies and generation ids. */ 2538 2539 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 2540 { 2541 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 2542 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 2543 * get validated by dst_ops->check on every use. We do this 2544 * because when a normal route referenced by an XFRM dst is 2545 * obsoleted we do not go looking around for all parent 2546 * referencing XFRM dsts so that we can invalidate them. It 2547 * is just too much work. Instead we make the checks here on 2548 * every use. For example: 2549 * 2550 * XFRM dst A --> IPv4 dst X 2551 * 2552 * X is the "xdst->route" of A (X is also the "dst->path" of A 2553 * in this example). If X is marked obsolete, "A" will not 2554 * notice. That's what we are validating here via the 2555 * stale_bundle() check. 2556 * 2557 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 2558 * be marked on it. 2559 * This will force stale_bundle() to fail on any xdst bundle with 2560 * this dst linked in it. 2561 */ 2562 if (dst->obsolete < 0 && !stale_bundle(dst)) 2563 return dst; 2564 2565 return NULL; 2566 } 2567 2568 static int stale_bundle(struct dst_entry *dst) 2569 { 2570 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 2571 } 2572 2573 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 2574 { 2575 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { 2576 dst->dev = dev_net(dev)->loopback_dev; 2577 dev_hold(dst->dev); 2578 dev_put(dev); 2579 } 2580 } 2581 EXPORT_SYMBOL(xfrm_dst_ifdown); 2582 2583 static void xfrm_link_failure(struct sk_buff *skb) 2584 { 2585 /* Impossible. Such dst must be popped before reaches point of failure. */ 2586 } 2587 2588 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 2589 { 2590 if (dst) { 2591 if (dst->obsolete) { 2592 dst_release(dst); 2593 dst = NULL; 2594 } 2595 } 2596 return dst; 2597 } 2598 2599 static void xfrm_init_pmtu(struct dst_entry *dst) 2600 { 2601 do { 2602 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2603 u32 pmtu, route_mtu_cached; 2604 2605 pmtu = dst_mtu(dst->child); 2606 xdst->child_mtu_cached = pmtu; 2607 2608 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 2609 2610 route_mtu_cached = dst_mtu(xdst->route); 2611 xdst->route_mtu_cached = route_mtu_cached; 2612 2613 if (pmtu > route_mtu_cached) 2614 pmtu = route_mtu_cached; 2615 2616 dst_metric_set(dst, RTAX_MTU, pmtu); 2617 } while ((dst = dst->next)); 2618 } 2619 2620 /* Check that the bundle accepts the flow and its components are 2621 * still valid. 2622 */ 2623 2624 static int xfrm_bundle_ok(struct xfrm_dst *first) 2625 { 2626 struct dst_entry *dst = &first->u.dst; 2627 struct xfrm_dst *last; 2628 u32 mtu; 2629 2630 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) || 2631 (dst->dev && !netif_running(dst->dev))) 2632 return 0; 2633 2634 if (dst->flags & DST_XFRM_QUEUE) 2635 return 1; 2636 2637 last = NULL; 2638 2639 do { 2640 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2641 2642 if (dst->xfrm->km.state != XFRM_STATE_VALID) 2643 return 0; 2644 if (xdst->xfrm_genid != dst->xfrm->genid) 2645 return 0; 2646 if (xdst->num_pols > 0 && 2647 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 2648 return 0; 2649 2650 mtu = dst_mtu(dst->child); 2651 if (xdst->child_mtu_cached != mtu) { 2652 last = xdst; 2653 xdst->child_mtu_cached = mtu; 2654 } 2655 2656 if (!dst_check(xdst->route, xdst->route_cookie)) 2657 return 0; 2658 mtu = dst_mtu(xdst->route); 2659 if (xdst->route_mtu_cached != mtu) { 2660 last = xdst; 2661 xdst->route_mtu_cached = mtu; 2662 } 2663 2664 dst = dst->child; 2665 } while (dst->xfrm); 2666 2667 if (likely(!last)) 2668 return 1; 2669 2670 mtu = last->child_mtu_cached; 2671 for (;;) { 2672 dst = &last->u.dst; 2673 2674 mtu = xfrm_state_mtu(dst->xfrm, mtu); 2675 if (mtu > last->route_mtu_cached) 2676 mtu = last->route_mtu_cached; 2677 dst_metric_set(dst, RTAX_MTU, mtu); 2678 2679 if (last == first) 2680 break; 2681 2682 last = (struct xfrm_dst *)last->u.dst.next; 2683 last->child_mtu_cached = mtu; 2684 } 2685 2686 return 1; 2687 } 2688 2689 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 2690 { 2691 return dst_metric_advmss(dst->path); 2692 } 2693 2694 static unsigned int xfrm_mtu(const struct dst_entry *dst) 2695 { 2696 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 2697 2698 return mtu ? : dst_mtu(dst->path); 2699 } 2700 2701 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 2702 const void *daddr) 2703 { 2704 const struct dst_entry *path = dst->path; 2705 2706 for (; dst != path; dst = dst->child) { 2707 const struct xfrm_state *xfrm = dst->xfrm; 2708 2709 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 2710 continue; 2711 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 2712 daddr = xfrm->coaddr; 2713 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 2714 daddr = &xfrm->id.daddr; 2715 } 2716 return daddr; 2717 } 2718 2719 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 2720 struct sk_buff *skb, 2721 const void *daddr) 2722 { 2723 const struct dst_entry *path = dst->path; 2724 2725 if (!skb) 2726 daddr = xfrm_get_dst_nexthop(dst, daddr); 2727 return path->ops->neigh_lookup(path, skb, daddr); 2728 } 2729 2730 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 2731 { 2732 const struct dst_entry *path = dst->path; 2733 2734 daddr = xfrm_get_dst_nexthop(dst, daddr); 2735 path->ops->confirm_neigh(path, daddr); 2736 } 2737 2738 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 2739 { 2740 int err = 0; 2741 2742 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 2743 return -EAFNOSUPPORT; 2744 2745 spin_lock(&xfrm_policy_afinfo_lock); 2746 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 2747 err = -EEXIST; 2748 else { 2749 struct dst_ops *dst_ops = afinfo->dst_ops; 2750 if (likely(dst_ops->kmem_cachep == NULL)) 2751 dst_ops->kmem_cachep = xfrm_dst_cache; 2752 if (likely(dst_ops->check == NULL)) 2753 dst_ops->check = xfrm_dst_check; 2754 if (likely(dst_ops->default_advmss == NULL)) 2755 dst_ops->default_advmss = xfrm_default_advmss; 2756 if (likely(dst_ops->mtu == NULL)) 2757 dst_ops->mtu = xfrm_mtu; 2758 if (likely(dst_ops->negative_advice == NULL)) 2759 dst_ops->negative_advice = xfrm_negative_advice; 2760 if (likely(dst_ops->link_failure == NULL)) 2761 dst_ops->link_failure = xfrm_link_failure; 2762 if (likely(dst_ops->neigh_lookup == NULL)) 2763 dst_ops->neigh_lookup = xfrm_neigh_lookup; 2764 if (likely(!dst_ops->confirm_neigh)) 2765 dst_ops->confirm_neigh = xfrm_confirm_neigh; 2766 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 2767 } 2768 spin_unlock(&xfrm_policy_afinfo_lock); 2769 2770 return err; 2771 } 2772 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 2773 2774 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 2775 { 2776 struct dst_ops *dst_ops = afinfo->dst_ops; 2777 int i; 2778 2779 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 2780 if (xfrm_policy_afinfo[i] != afinfo) 2781 continue; 2782 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 2783 break; 2784 } 2785 2786 synchronize_rcu(); 2787 2788 dst_ops->kmem_cachep = NULL; 2789 dst_ops->check = NULL; 2790 dst_ops->negative_advice = NULL; 2791 dst_ops->link_failure = NULL; 2792 } 2793 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 2794 2795 #ifdef CONFIG_XFRM_STATISTICS 2796 static int __net_init xfrm_statistics_init(struct net *net) 2797 { 2798 int rv; 2799 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 2800 if (!net->mib.xfrm_statistics) 2801 return -ENOMEM; 2802 rv = xfrm_proc_init(net); 2803 if (rv < 0) 2804 free_percpu(net->mib.xfrm_statistics); 2805 return rv; 2806 } 2807 2808 static void xfrm_statistics_fini(struct net *net) 2809 { 2810 xfrm_proc_fini(net); 2811 free_percpu(net->mib.xfrm_statistics); 2812 } 2813 #else 2814 static int __net_init xfrm_statistics_init(struct net *net) 2815 { 2816 return 0; 2817 } 2818 2819 static void xfrm_statistics_fini(struct net *net) 2820 { 2821 } 2822 #endif 2823 2824 static int __net_init xfrm_policy_init(struct net *net) 2825 { 2826 unsigned int hmask, sz; 2827 int dir; 2828 2829 if (net_eq(net, &init_net)) 2830 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 2831 sizeof(struct xfrm_dst), 2832 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 2833 NULL); 2834 2835 hmask = 8 - 1; 2836 sz = (hmask+1) * sizeof(struct hlist_head); 2837 2838 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 2839 if (!net->xfrm.policy_byidx) 2840 goto out_byidx; 2841 net->xfrm.policy_idx_hmask = hmask; 2842 2843 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2844 struct xfrm_policy_hash *htab; 2845 2846 net->xfrm.policy_count[dir] = 0; 2847 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 2848 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 2849 2850 htab = &net->xfrm.policy_bydst[dir]; 2851 htab->table = xfrm_hash_alloc(sz); 2852 if (!htab->table) 2853 goto out_bydst; 2854 htab->hmask = hmask; 2855 htab->dbits4 = 32; 2856 htab->sbits4 = 32; 2857 htab->dbits6 = 128; 2858 htab->sbits6 = 128; 2859 } 2860 net->xfrm.policy_hthresh.lbits4 = 32; 2861 net->xfrm.policy_hthresh.rbits4 = 32; 2862 net->xfrm.policy_hthresh.lbits6 = 128; 2863 net->xfrm.policy_hthresh.rbits6 = 128; 2864 2865 seqlock_init(&net->xfrm.policy_hthresh.lock); 2866 2867 INIT_LIST_HEAD(&net->xfrm.policy_all); 2868 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 2869 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 2870 if (net_eq(net, &init_net)) 2871 xfrm_dev_init(); 2872 return 0; 2873 2874 out_bydst: 2875 for (dir--; dir >= 0; dir--) { 2876 struct xfrm_policy_hash *htab; 2877 2878 htab = &net->xfrm.policy_bydst[dir]; 2879 xfrm_hash_free(htab->table, sz); 2880 } 2881 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2882 out_byidx: 2883 return -ENOMEM; 2884 } 2885 2886 static void xfrm_policy_fini(struct net *net) 2887 { 2888 unsigned int sz; 2889 int dir; 2890 2891 flush_work(&net->xfrm.policy_hash_work); 2892 #ifdef CONFIG_XFRM_SUB_POLICY 2893 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 2894 #endif 2895 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 2896 2897 WARN_ON(!list_empty(&net->xfrm.policy_all)); 2898 2899 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2900 struct xfrm_policy_hash *htab; 2901 2902 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 2903 2904 htab = &net->xfrm.policy_bydst[dir]; 2905 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 2906 WARN_ON(!hlist_empty(htab->table)); 2907 xfrm_hash_free(htab->table, sz); 2908 } 2909 2910 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 2911 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 2912 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2913 } 2914 2915 static int __net_init xfrm_net_init(struct net *net) 2916 { 2917 int rv; 2918 2919 /* Initialize the per-net locks here */ 2920 spin_lock_init(&net->xfrm.xfrm_state_lock); 2921 spin_lock_init(&net->xfrm.xfrm_policy_lock); 2922 mutex_init(&net->xfrm.xfrm_cfg_mutex); 2923 2924 rv = xfrm_statistics_init(net); 2925 if (rv < 0) 2926 goto out_statistics; 2927 rv = xfrm_state_init(net); 2928 if (rv < 0) 2929 goto out_state; 2930 rv = xfrm_policy_init(net); 2931 if (rv < 0) 2932 goto out_policy; 2933 rv = xfrm_sysctl_init(net); 2934 if (rv < 0) 2935 goto out_sysctl; 2936 2937 return 0; 2938 2939 out_sysctl: 2940 xfrm_policy_fini(net); 2941 out_policy: 2942 xfrm_state_fini(net); 2943 out_state: 2944 xfrm_statistics_fini(net); 2945 out_statistics: 2946 return rv; 2947 } 2948 2949 static void __net_exit xfrm_net_exit(struct net *net) 2950 { 2951 xfrm_sysctl_fini(net); 2952 xfrm_policy_fini(net); 2953 xfrm_state_fini(net); 2954 xfrm_statistics_fini(net); 2955 } 2956 2957 static struct pernet_operations __net_initdata xfrm_net_ops = { 2958 .init = xfrm_net_init, 2959 .exit = xfrm_net_exit, 2960 }; 2961 2962 void __init xfrm_init(void) 2963 { 2964 int i; 2965 2966 xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work), 2967 GFP_KERNEL); 2968 BUG_ON(!xfrm_pcpu_work); 2969 2970 for (i = 0; i < NR_CPUS; i++) 2971 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn); 2972 2973 register_pernet_subsys(&xfrm_net_ops); 2974 seqcount_init(&xfrm_policy_hash_generation); 2975 xfrm_input_init(); 2976 } 2977 2978 #ifdef CONFIG_AUDITSYSCALL 2979 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 2980 struct audit_buffer *audit_buf) 2981 { 2982 struct xfrm_sec_ctx *ctx = xp->security; 2983 struct xfrm_selector *sel = &xp->selector; 2984 2985 if (ctx) 2986 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 2987 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 2988 2989 switch (sel->family) { 2990 case AF_INET: 2991 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 2992 if (sel->prefixlen_s != 32) 2993 audit_log_format(audit_buf, " src_prefixlen=%d", 2994 sel->prefixlen_s); 2995 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 2996 if (sel->prefixlen_d != 32) 2997 audit_log_format(audit_buf, " dst_prefixlen=%d", 2998 sel->prefixlen_d); 2999 break; 3000 case AF_INET6: 3001 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 3002 if (sel->prefixlen_s != 128) 3003 audit_log_format(audit_buf, " src_prefixlen=%d", 3004 sel->prefixlen_s); 3005 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 3006 if (sel->prefixlen_d != 128) 3007 audit_log_format(audit_buf, " dst_prefixlen=%d", 3008 sel->prefixlen_d); 3009 break; 3010 } 3011 } 3012 3013 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 3014 { 3015 struct audit_buffer *audit_buf; 3016 3017 audit_buf = xfrm_audit_start("SPD-add"); 3018 if (audit_buf == NULL) 3019 return; 3020 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3021 audit_log_format(audit_buf, " res=%u", result); 3022 xfrm_audit_common_policyinfo(xp, audit_buf); 3023 audit_log_end(audit_buf); 3024 } 3025 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 3026 3027 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 3028 bool task_valid) 3029 { 3030 struct audit_buffer *audit_buf; 3031 3032 audit_buf = xfrm_audit_start("SPD-delete"); 3033 if (audit_buf == NULL) 3034 return; 3035 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3036 audit_log_format(audit_buf, " res=%u", result); 3037 xfrm_audit_common_policyinfo(xp, audit_buf); 3038 audit_log_end(audit_buf); 3039 } 3040 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 3041 #endif 3042 3043 #ifdef CONFIG_XFRM_MIGRATE 3044 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 3045 const struct xfrm_selector *sel_tgt) 3046 { 3047 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 3048 if (sel_tgt->family == sel_cmp->family && 3049 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 3050 sel_cmp->family) && 3051 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 3052 sel_cmp->family) && 3053 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 3054 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 3055 return true; 3056 } 3057 } else { 3058 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 3059 return true; 3060 } 3061 } 3062 return false; 3063 } 3064 3065 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 3066 u8 dir, u8 type, struct net *net) 3067 { 3068 struct xfrm_policy *pol, *ret = NULL; 3069 struct hlist_head *chain; 3070 u32 priority = ~0U; 3071 3072 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 3073 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 3074 hlist_for_each_entry(pol, chain, bydst) { 3075 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3076 pol->type == type) { 3077 ret = pol; 3078 priority = ret->priority; 3079 break; 3080 } 3081 } 3082 chain = &net->xfrm.policy_inexact[dir]; 3083 hlist_for_each_entry(pol, chain, bydst) { 3084 if ((pol->priority >= priority) && ret) 3085 break; 3086 3087 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3088 pol->type == type) { 3089 ret = pol; 3090 break; 3091 } 3092 } 3093 3094 xfrm_pol_hold(ret); 3095 3096 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 3097 3098 return ret; 3099 } 3100 3101 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 3102 { 3103 int match = 0; 3104 3105 if (t->mode == m->mode && t->id.proto == m->proto && 3106 (m->reqid == 0 || t->reqid == m->reqid)) { 3107 switch (t->mode) { 3108 case XFRM_MODE_TUNNEL: 3109 case XFRM_MODE_BEET: 3110 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 3111 m->old_family) && 3112 xfrm_addr_equal(&t->saddr, &m->old_saddr, 3113 m->old_family)) { 3114 match = 1; 3115 } 3116 break; 3117 case XFRM_MODE_TRANSPORT: 3118 /* in case of transport mode, template does not store 3119 any IP addresses, hence we just compare mode and 3120 protocol */ 3121 match = 1; 3122 break; 3123 default: 3124 break; 3125 } 3126 } 3127 return match; 3128 } 3129 3130 /* update endpoint address(es) of template(s) */ 3131 static int xfrm_policy_migrate(struct xfrm_policy *pol, 3132 struct xfrm_migrate *m, int num_migrate) 3133 { 3134 struct xfrm_migrate *mp; 3135 int i, j, n = 0; 3136 3137 write_lock_bh(&pol->lock); 3138 if (unlikely(pol->walk.dead)) { 3139 /* target policy has been deleted */ 3140 write_unlock_bh(&pol->lock); 3141 return -ENOENT; 3142 } 3143 3144 for (i = 0; i < pol->xfrm_nr; i++) { 3145 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 3146 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 3147 continue; 3148 n++; 3149 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 3150 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 3151 continue; 3152 /* update endpoints */ 3153 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 3154 sizeof(pol->xfrm_vec[i].id.daddr)); 3155 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 3156 sizeof(pol->xfrm_vec[i].saddr)); 3157 pol->xfrm_vec[i].encap_family = mp->new_family; 3158 /* flush bundles */ 3159 atomic_inc(&pol->genid); 3160 } 3161 } 3162 3163 write_unlock_bh(&pol->lock); 3164 3165 if (!n) 3166 return -ENODATA; 3167 3168 return 0; 3169 } 3170 3171 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 3172 { 3173 int i, j; 3174 3175 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 3176 return -EINVAL; 3177 3178 for (i = 0; i < num_migrate; i++) { 3179 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 3180 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 3181 return -EINVAL; 3182 3183 /* check if there is any duplicated entry */ 3184 for (j = i + 1; j < num_migrate; j++) { 3185 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 3186 sizeof(m[i].old_daddr)) && 3187 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 3188 sizeof(m[i].old_saddr)) && 3189 m[i].proto == m[j].proto && 3190 m[i].mode == m[j].mode && 3191 m[i].reqid == m[j].reqid && 3192 m[i].old_family == m[j].old_family) 3193 return -EINVAL; 3194 } 3195 } 3196 3197 return 0; 3198 } 3199 3200 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 3201 struct xfrm_migrate *m, int num_migrate, 3202 struct xfrm_kmaddress *k, struct net *net, 3203 struct xfrm_encap_tmpl *encap) 3204 { 3205 int i, err, nx_cur = 0, nx_new = 0; 3206 struct xfrm_policy *pol = NULL; 3207 struct xfrm_state *x, *xc; 3208 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 3209 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 3210 struct xfrm_migrate *mp; 3211 3212 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 3213 goto out; 3214 3215 /* Stage 1 - find policy */ 3216 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 3217 err = -ENOENT; 3218 goto out; 3219 } 3220 3221 /* Stage 2 - find and update state(s) */ 3222 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 3223 if ((x = xfrm_migrate_state_find(mp, net))) { 3224 x_cur[nx_cur] = x; 3225 nx_cur++; 3226 xc = xfrm_state_migrate(x, mp, encap); 3227 if (xc) { 3228 x_new[nx_new] = xc; 3229 nx_new++; 3230 } else { 3231 err = -ENODATA; 3232 goto restore_state; 3233 } 3234 } 3235 } 3236 3237 /* Stage 3 - update policy */ 3238 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 3239 goto restore_state; 3240 3241 /* Stage 4 - delete old state(s) */ 3242 if (nx_cur) { 3243 xfrm_states_put(x_cur, nx_cur); 3244 xfrm_states_delete(x_cur, nx_cur); 3245 } 3246 3247 /* Stage 5 - announce */ 3248 km_migrate(sel, dir, type, m, num_migrate, k, encap); 3249 3250 xfrm_pol_put(pol); 3251 3252 return 0; 3253 out: 3254 return err; 3255 3256 restore_state: 3257 if (pol) 3258 xfrm_pol_put(pol); 3259 if (nx_cur) 3260 xfrm_states_put(x_cur, nx_cur); 3261 if (nx_new) 3262 xfrm_states_delete(x_new, nx_new); 3263 3264 return err; 3265 } 3266 EXPORT_SYMBOL(xfrm_migrate); 3267 #endif 3268