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/audit.h> 28 #include <net/dst.h> 29 #include <net/flow.h> 30 #include <net/xfrm.h> 31 #include <net/ip.h> 32 #ifdef CONFIG_XFRM_STATISTICS 33 #include <net/snmp.h> 34 #endif 35 36 #include "xfrm_hash.h" 37 38 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 39 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 40 #define XFRM_MAX_QUEUE_LEN 100 41 42 DEFINE_MUTEX(xfrm_cfg_mutex); 43 EXPORT_SYMBOL(xfrm_cfg_mutex); 44 45 static DEFINE_SPINLOCK(xfrm_policy_sk_bundle_lock); 46 static struct dst_entry *xfrm_policy_sk_bundles; 47 static DEFINE_RWLOCK(xfrm_policy_lock); 48 49 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 50 static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO] 51 __read_mostly; 52 53 static struct kmem_cache *xfrm_dst_cache __read_mostly; 54 55 static void xfrm_init_pmtu(struct dst_entry *dst); 56 static int stale_bundle(struct dst_entry *dst); 57 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 58 static void xfrm_policy_queue_process(unsigned long arg); 59 60 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 61 int dir); 62 63 static inline bool 64 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 65 { 66 const struct flowi4 *fl4 = &fl->u.ip4; 67 68 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 69 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 70 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 71 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 72 (fl4->flowi4_proto == sel->proto || !sel->proto) && 73 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 74 } 75 76 static inline bool 77 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 78 { 79 const struct flowi6 *fl6 = &fl->u.ip6; 80 81 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 82 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 83 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 84 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 85 (fl6->flowi6_proto == sel->proto || !sel->proto) && 86 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 87 } 88 89 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 90 unsigned short family) 91 { 92 switch (family) { 93 case AF_INET: 94 return __xfrm4_selector_match(sel, fl); 95 case AF_INET6: 96 return __xfrm6_selector_match(sel, fl); 97 } 98 return false; 99 } 100 101 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 102 { 103 struct xfrm_policy_afinfo *afinfo; 104 105 if (unlikely(family >= NPROTO)) 106 return NULL; 107 rcu_read_lock(); 108 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 109 if (unlikely(!afinfo)) 110 rcu_read_unlock(); 111 return afinfo; 112 } 113 114 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo) 115 { 116 rcu_read_unlock(); 117 } 118 119 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, 120 const xfrm_address_t *saddr, 121 const xfrm_address_t *daddr, 122 int family) 123 { 124 struct xfrm_policy_afinfo *afinfo; 125 struct dst_entry *dst; 126 127 afinfo = xfrm_policy_get_afinfo(family); 128 if (unlikely(afinfo == NULL)) 129 return ERR_PTR(-EAFNOSUPPORT); 130 131 dst = afinfo->dst_lookup(net, tos, saddr, daddr); 132 133 xfrm_policy_put_afinfo(afinfo); 134 135 return dst; 136 } 137 138 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos, 139 xfrm_address_t *prev_saddr, 140 xfrm_address_t *prev_daddr, 141 int family) 142 { 143 struct net *net = xs_net(x); 144 xfrm_address_t *saddr = &x->props.saddr; 145 xfrm_address_t *daddr = &x->id.daddr; 146 struct dst_entry *dst; 147 148 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 149 saddr = x->coaddr; 150 daddr = prev_daddr; 151 } 152 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 153 saddr = prev_saddr; 154 daddr = x->coaddr; 155 } 156 157 dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family); 158 159 if (!IS_ERR(dst)) { 160 if (prev_saddr != saddr) 161 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 162 if (prev_daddr != daddr) 163 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 164 } 165 166 return dst; 167 } 168 169 static inline unsigned long make_jiffies(long secs) 170 { 171 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 172 return MAX_SCHEDULE_TIMEOUT-1; 173 else 174 return secs*HZ; 175 } 176 177 static void xfrm_policy_timer(unsigned long data) 178 { 179 struct xfrm_policy *xp = (struct xfrm_policy*)data; 180 unsigned long now = get_seconds(); 181 long next = LONG_MAX; 182 int warn = 0; 183 int dir; 184 185 read_lock(&xp->lock); 186 187 if (unlikely(xp->walk.dead)) 188 goto out; 189 190 dir = xfrm_policy_id2dir(xp->index); 191 192 if (xp->lft.hard_add_expires_seconds) { 193 long tmo = xp->lft.hard_add_expires_seconds + 194 xp->curlft.add_time - now; 195 if (tmo <= 0) 196 goto expired; 197 if (tmo < next) 198 next = tmo; 199 } 200 if (xp->lft.hard_use_expires_seconds) { 201 long tmo = xp->lft.hard_use_expires_seconds + 202 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 203 if (tmo <= 0) 204 goto expired; 205 if (tmo < next) 206 next = tmo; 207 } 208 if (xp->lft.soft_add_expires_seconds) { 209 long tmo = xp->lft.soft_add_expires_seconds + 210 xp->curlft.add_time - now; 211 if (tmo <= 0) { 212 warn = 1; 213 tmo = XFRM_KM_TIMEOUT; 214 } 215 if (tmo < next) 216 next = tmo; 217 } 218 if (xp->lft.soft_use_expires_seconds) { 219 long tmo = xp->lft.soft_use_expires_seconds + 220 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 221 if (tmo <= 0) { 222 warn = 1; 223 tmo = XFRM_KM_TIMEOUT; 224 } 225 if (tmo < next) 226 next = tmo; 227 } 228 229 if (warn) 230 km_policy_expired(xp, dir, 0, 0); 231 if (next != LONG_MAX && 232 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 233 xfrm_pol_hold(xp); 234 235 out: 236 read_unlock(&xp->lock); 237 xfrm_pol_put(xp); 238 return; 239 240 expired: 241 read_unlock(&xp->lock); 242 if (!xfrm_policy_delete(xp, dir)) 243 km_policy_expired(xp, dir, 1, 0); 244 xfrm_pol_put(xp); 245 } 246 247 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo) 248 { 249 struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo); 250 251 if (unlikely(pol->walk.dead)) 252 flo = NULL; 253 else 254 xfrm_pol_hold(pol); 255 256 return flo; 257 } 258 259 static int xfrm_policy_flo_check(struct flow_cache_object *flo) 260 { 261 struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo); 262 263 return !pol->walk.dead; 264 } 265 266 static void xfrm_policy_flo_delete(struct flow_cache_object *flo) 267 { 268 xfrm_pol_put(container_of(flo, struct xfrm_policy, flo)); 269 } 270 271 static const struct flow_cache_ops xfrm_policy_fc_ops = { 272 .get = xfrm_policy_flo_get, 273 .check = xfrm_policy_flo_check, 274 .delete = xfrm_policy_flo_delete, 275 }; 276 277 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 278 * SPD calls. 279 */ 280 281 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 282 { 283 struct xfrm_policy *policy; 284 285 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 286 287 if (policy) { 288 write_pnet(&policy->xp_net, net); 289 INIT_LIST_HEAD(&policy->walk.all); 290 INIT_HLIST_NODE(&policy->bydst); 291 INIT_HLIST_NODE(&policy->byidx); 292 rwlock_init(&policy->lock); 293 atomic_set(&policy->refcnt, 1); 294 skb_queue_head_init(&policy->polq.hold_queue); 295 setup_timer(&policy->timer, xfrm_policy_timer, 296 (unsigned long)policy); 297 setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process, 298 (unsigned long)policy); 299 policy->flo.ops = &xfrm_policy_fc_ops; 300 } 301 return policy; 302 } 303 EXPORT_SYMBOL(xfrm_policy_alloc); 304 305 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 306 307 void xfrm_policy_destroy(struct xfrm_policy *policy) 308 { 309 BUG_ON(!policy->walk.dead); 310 311 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 312 BUG(); 313 314 security_xfrm_policy_free(policy->security); 315 kfree(policy); 316 } 317 EXPORT_SYMBOL(xfrm_policy_destroy); 318 319 static void xfrm_queue_purge(struct sk_buff_head *list) 320 { 321 struct sk_buff *skb; 322 323 while ((skb = skb_dequeue(list)) != NULL) 324 kfree_skb(skb); 325 } 326 327 /* Rule must be locked. Release descentant resources, announce 328 * entry dead. The rule must be unlinked from lists to the moment. 329 */ 330 331 static void xfrm_policy_kill(struct xfrm_policy *policy) 332 { 333 policy->walk.dead = 1; 334 335 atomic_inc(&policy->genid); 336 337 del_timer(&policy->polq.hold_timer); 338 xfrm_queue_purge(&policy->polq.hold_queue); 339 340 if (del_timer(&policy->timer)) 341 xfrm_pol_put(policy); 342 343 xfrm_pol_put(policy); 344 } 345 346 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 347 348 static inline unsigned int idx_hash(struct net *net, u32 index) 349 { 350 return __idx_hash(index, net->xfrm.policy_idx_hmask); 351 } 352 353 static struct hlist_head *policy_hash_bysel(struct net *net, 354 const struct xfrm_selector *sel, 355 unsigned short family, int dir) 356 { 357 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 358 unsigned int hash = __sel_hash(sel, family, hmask); 359 360 return (hash == hmask + 1 ? 361 &net->xfrm.policy_inexact[dir] : 362 net->xfrm.policy_bydst[dir].table + hash); 363 } 364 365 static struct hlist_head *policy_hash_direct(struct net *net, 366 const xfrm_address_t *daddr, 367 const xfrm_address_t *saddr, 368 unsigned short family, int dir) 369 { 370 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 371 unsigned int hash = __addr_hash(daddr, saddr, family, hmask); 372 373 return net->xfrm.policy_bydst[dir].table + hash; 374 } 375 376 static void xfrm_dst_hash_transfer(struct hlist_head *list, 377 struct hlist_head *ndsttable, 378 unsigned int nhashmask) 379 { 380 struct hlist_node *tmp, *entry0 = NULL; 381 struct xfrm_policy *pol; 382 unsigned int h0 = 0; 383 384 redo: 385 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 386 unsigned int h; 387 388 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 389 pol->family, nhashmask); 390 if (!entry0) { 391 hlist_del(&pol->bydst); 392 hlist_add_head(&pol->bydst, ndsttable+h); 393 h0 = h; 394 } else { 395 if (h != h0) 396 continue; 397 hlist_del(&pol->bydst); 398 hlist_add_after(entry0, &pol->bydst); 399 } 400 entry0 = &pol->bydst; 401 } 402 if (!hlist_empty(list)) { 403 entry0 = NULL; 404 goto redo; 405 } 406 } 407 408 static void xfrm_idx_hash_transfer(struct hlist_head *list, 409 struct hlist_head *nidxtable, 410 unsigned int nhashmask) 411 { 412 struct hlist_node *tmp; 413 struct xfrm_policy *pol; 414 415 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 416 unsigned int h; 417 418 h = __idx_hash(pol->index, nhashmask); 419 hlist_add_head(&pol->byidx, nidxtable+h); 420 } 421 } 422 423 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 424 { 425 return ((old_hmask + 1) << 1) - 1; 426 } 427 428 static void xfrm_bydst_resize(struct net *net, int dir) 429 { 430 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 431 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 432 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 433 struct hlist_head *odst = net->xfrm.policy_bydst[dir].table; 434 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 435 int i; 436 437 if (!ndst) 438 return; 439 440 write_lock_bh(&xfrm_policy_lock); 441 442 for (i = hmask; i >= 0; i--) 443 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask); 444 445 net->xfrm.policy_bydst[dir].table = ndst; 446 net->xfrm.policy_bydst[dir].hmask = nhashmask; 447 448 write_unlock_bh(&xfrm_policy_lock); 449 450 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 451 } 452 453 static void xfrm_byidx_resize(struct net *net, int total) 454 { 455 unsigned int hmask = net->xfrm.policy_idx_hmask; 456 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 457 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 458 struct hlist_head *oidx = net->xfrm.policy_byidx; 459 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 460 int i; 461 462 if (!nidx) 463 return; 464 465 write_lock_bh(&xfrm_policy_lock); 466 467 for (i = hmask; i >= 0; i--) 468 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 469 470 net->xfrm.policy_byidx = nidx; 471 net->xfrm.policy_idx_hmask = nhashmask; 472 473 write_unlock_bh(&xfrm_policy_lock); 474 475 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 476 } 477 478 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 479 { 480 unsigned int cnt = net->xfrm.policy_count[dir]; 481 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 482 483 if (total) 484 *total += cnt; 485 486 if ((hmask + 1) < xfrm_policy_hashmax && 487 cnt > hmask) 488 return 1; 489 490 return 0; 491 } 492 493 static inline int xfrm_byidx_should_resize(struct net *net, int total) 494 { 495 unsigned int hmask = net->xfrm.policy_idx_hmask; 496 497 if ((hmask + 1) < xfrm_policy_hashmax && 498 total > hmask) 499 return 1; 500 501 return 0; 502 } 503 504 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 505 { 506 read_lock_bh(&xfrm_policy_lock); 507 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 508 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 509 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 510 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 511 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 512 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 513 si->spdhcnt = net->xfrm.policy_idx_hmask; 514 si->spdhmcnt = xfrm_policy_hashmax; 515 read_unlock_bh(&xfrm_policy_lock); 516 } 517 EXPORT_SYMBOL(xfrm_spd_getinfo); 518 519 static DEFINE_MUTEX(hash_resize_mutex); 520 static void xfrm_hash_resize(struct work_struct *work) 521 { 522 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 523 int dir, total; 524 525 mutex_lock(&hash_resize_mutex); 526 527 total = 0; 528 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) { 529 if (xfrm_bydst_should_resize(net, dir, &total)) 530 xfrm_bydst_resize(net, dir); 531 } 532 if (xfrm_byidx_should_resize(net, total)) 533 xfrm_byidx_resize(net, total); 534 535 mutex_unlock(&hash_resize_mutex); 536 } 537 538 /* Generate new index... KAME seems to generate them ordered by cost 539 * of an absolute inpredictability of ordering of rules. This will not pass. */ 540 static u32 xfrm_gen_index(struct net *net, int dir) 541 { 542 static u32 idx_generator; 543 544 for (;;) { 545 struct hlist_head *list; 546 struct xfrm_policy *p; 547 u32 idx; 548 int found; 549 550 idx = (idx_generator | dir); 551 idx_generator += 8; 552 if (idx == 0) 553 idx = 8; 554 list = net->xfrm.policy_byidx + idx_hash(net, idx); 555 found = 0; 556 hlist_for_each_entry(p, list, byidx) { 557 if (p->index == idx) { 558 found = 1; 559 break; 560 } 561 } 562 if (!found) 563 return idx; 564 } 565 } 566 567 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 568 { 569 u32 *p1 = (u32 *) s1; 570 u32 *p2 = (u32 *) s2; 571 int len = sizeof(struct xfrm_selector) / sizeof(u32); 572 int i; 573 574 for (i = 0; i < len; i++) { 575 if (p1[i] != p2[i]) 576 return 1; 577 } 578 579 return 0; 580 } 581 582 static void xfrm_policy_requeue(struct xfrm_policy *old, 583 struct xfrm_policy *new) 584 { 585 struct xfrm_policy_queue *pq = &old->polq; 586 struct sk_buff_head list; 587 588 __skb_queue_head_init(&list); 589 590 spin_lock_bh(&pq->hold_queue.lock); 591 skb_queue_splice_init(&pq->hold_queue, &list); 592 del_timer(&pq->hold_timer); 593 spin_unlock_bh(&pq->hold_queue.lock); 594 595 if (skb_queue_empty(&list)) 596 return; 597 598 pq = &new->polq; 599 600 spin_lock_bh(&pq->hold_queue.lock); 601 skb_queue_splice(&list, &pq->hold_queue); 602 pq->timeout = XFRM_QUEUE_TMO_MIN; 603 mod_timer(&pq->hold_timer, jiffies); 604 spin_unlock_bh(&pq->hold_queue.lock); 605 } 606 607 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 608 struct xfrm_policy *pol) 609 { 610 u32 mark = policy->mark.v & policy->mark.m; 611 612 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 613 return true; 614 615 if ((mark & pol->mark.m) == pol->mark.v && 616 policy->priority == pol->priority) 617 return true; 618 619 return false; 620 } 621 622 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 623 { 624 struct net *net = xp_net(policy); 625 struct xfrm_policy *pol; 626 struct xfrm_policy *delpol; 627 struct hlist_head *chain; 628 struct hlist_node *newpos; 629 630 write_lock_bh(&xfrm_policy_lock); 631 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 632 delpol = NULL; 633 newpos = NULL; 634 hlist_for_each_entry(pol, chain, bydst) { 635 if (pol->type == policy->type && 636 !selector_cmp(&pol->selector, &policy->selector) && 637 xfrm_policy_mark_match(policy, pol) && 638 xfrm_sec_ctx_match(pol->security, policy->security) && 639 !WARN_ON(delpol)) { 640 if (excl) { 641 write_unlock_bh(&xfrm_policy_lock); 642 return -EEXIST; 643 } 644 delpol = pol; 645 if (policy->priority > pol->priority) 646 continue; 647 } else if (policy->priority >= pol->priority) { 648 newpos = &pol->bydst; 649 continue; 650 } 651 if (delpol) 652 break; 653 } 654 if (newpos) 655 hlist_add_after(newpos, &policy->bydst); 656 else 657 hlist_add_head(&policy->bydst, chain); 658 xfrm_pol_hold(policy); 659 net->xfrm.policy_count[dir]++; 660 atomic_inc(&flow_cache_genid); 661 662 /* After previous checking, family can either be AF_INET or AF_INET6 */ 663 if (policy->family == AF_INET) 664 rt_genid_bump_ipv4(net); 665 else 666 rt_genid_bump_ipv6(net); 667 668 if (delpol) { 669 xfrm_policy_requeue(delpol, policy); 670 __xfrm_policy_unlink(delpol, dir); 671 } 672 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir); 673 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 674 policy->curlft.add_time = get_seconds(); 675 policy->curlft.use_time = 0; 676 if (!mod_timer(&policy->timer, jiffies + HZ)) 677 xfrm_pol_hold(policy); 678 list_add(&policy->walk.all, &net->xfrm.policy_all); 679 write_unlock_bh(&xfrm_policy_lock); 680 681 if (delpol) 682 xfrm_policy_kill(delpol); 683 else if (xfrm_bydst_should_resize(net, dir, NULL)) 684 schedule_work(&net->xfrm.policy_hash_work); 685 686 return 0; 687 } 688 EXPORT_SYMBOL(xfrm_policy_insert); 689 690 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type, 691 int dir, struct xfrm_selector *sel, 692 struct xfrm_sec_ctx *ctx, int delete, 693 int *err) 694 { 695 struct xfrm_policy *pol, *ret; 696 struct hlist_head *chain; 697 698 *err = 0; 699 write_lock_bh(&xfrm_policy_lock); 700 chain = policy_hash_bysel(net, sel, sel->family, dir); 701 ret = NULL; 702 hlist_for_each_entry(pol, chain, bydst) { 703 if (pol->type == type && 704 (mark & pol->mark.m) == pol->mark.v && 705 !selector_cmp(sel, &pol->selector) && 706 xfrm_sec_ctx_match(ctx, pol->security)) { 707 xfrm_pol_hold(pol); 708 if (delete) { 709 *err = security_xfrm_policy_delete( 710 pol->security); 711 if (*err) { 712 write_unlock_bh(&xfrm_policy_lock); 713 return pol; 714 } 715 __xfrm_policy_unlink(pol, dir); 716 } 717 ret = pol; 718 break; 719 } 720 } 721 write_unlock_bh(&xfrm_policy_lock); 722 723 if (ret && delete) 724 xfrm_policy_kill(ret); 725 return ret; 726 } 727 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 728 729 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type, 730 int dir, u32 id, int delete, int *err) 731 { 732 struct xfrm_policy *pol, *ret; 733 struct hlist_head *chain; 734 735 *err = -ENOENT; 736 if (xfrm_policy_id2dir(id) != dir) 737 return NULL; 738 739 *err = 0; 740 write_lock_bh(&xfrm_policy_lock); 741 chain = net->xfrm.policy_byidx + idx_hash(net, id); 742 ret = NULL; 743 hlist_for_each_entry(pol, chain, byidx) { 744 if (pol->type == type && pol->index == id && 745 (mark & pol->mark.m) == pol->mark.v) { 746 xfrm_pol_hold(pol); 747 if (delete) { 748 *err = security_xfrm_policy_delete( 749 pol->security); 750 if (*err) { 751 write_unlock_bh(&xfrm_policy_lock); 752 return pol; 753 } 754 __xfrm_policy_unlink(pol, dir); 755 } 756 ret = pol; 757 break; 758 } 759 } 760 write_unlock_bh(&xfrm_policy_lock); 761 762 if (ret && delete) 763 xfrm_policy_kill(ret); 764 return ret; 765 } 766 EXPORT_SYMBOL(xfrm_policy_byid); 767 768 #ifdef CONFIG_SECURITY_NETWORK_XFRM 769 static inline int 770 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info) 771 { 772 int dir, err = 0; 773 774 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 775 struct xfrm_policy *pol; 776 int i; 777 778 hlist_for_each_entry(pol, 779 &net->xfrm.policy_inexact[dir], bydst) { 780 if (pol->type != type) 781 continue; 782 err = security_xfrm_policy_delete(pol->security); 783 if (err) { 784 xfrm_audit_policy_delete(pol, 0, 785 audit_info->loginuid, 786 audit_info->sessionid, 787 audit_info->secid); 788 return err; 789 } 790 } 791 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 792 hlist_for_each_entry(pol, 793 net->xfrm.policy_bydst[dir].table + i, 794 bydst) { 795 if (pol->type != type) 796 continue; 797 err = security_xfrm_policy_delete( 798 pol->security); 799 if (err) { 800 xfrm_audit_policy_delete(pol, 0, 801 audit_info->loginuid, 802 audit_info->sessionid, 803 audit_info->secid); 804 return err; 805 } 806 } 807 } 808 } 809 return err; 810 } 811 #else 812 static inline int 813 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info) 814 { 815 return 0; 816 } 817 #endif 818 819 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info) 820 { 821 int dir, err = 0, cnt = 0; 822 823 write_lock_bh(&xfrm_policy_lock); 824 825 err = xfrm_policy_flush_secctx_check(net, type, audit_info); 826 if (err) 827 goto out; 828 829 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 830 struct xfrm_policy *pol; 831 int i; 832 833 again1: 834 hlist_for_each_entry(pol, 835 &net->xfrm.policy_inexact[dir], bydst) { 836 if (pol->type != type) 837 continue; 838 __xfrm_policy_unlink(pol, dir); 839 write_unlock_bh(&xfrm_policy_lock); 840 cnt++; 841 842 xfrm_audit_policy_delete(pol, 1, audit_info->loginuid, 843 audit_info->sessionid, 844 audit_info->secid); 845 846 xfrm_policy_kill(pol); 847 848 write_lock_bh(&xfrm_policy_lock); 849 goto again1; 850 } 851 852 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 853 again2: 854 hlist_for_each_entry(pol, 855 net->xfrm.policy_bydst[dir].table + i, 856 bydst) { 857 if (pol->type != type) 858 continue; 859 __xfrm_policy_unlink(pol, dir); 860 write_unlock_bh(&xfrm_policy_lock); 861 cnt++; 862 863 xfrm_audit_policy_delete(pol, 1, 864 audit_info->loginuid, 865 audit_info->sessionid, 866 audit_info->secid); 867 xfrm_policy_kill(pol); 868 869 write_lock_bh(&xfrm_policy_lock); 870 goto again2; 871 } 872 } 873 874 } 875 if (!cnt) 876 err = -ESRCH; 877 out: 878 write_unlock_bh(&xfrm_policy_lock); 879 return err; 880 } 881 EXPORT_SYMBOL(xfrm_policy_flush); 882 883 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 884 int (*func)(struct xfrm_policy *, int, int, void*), 885 void *data) 886 { 887 struct xfrm_policy *pol; 888 struct xfrm_policy_walk_entry *x; 889 int error = 0; 890 891 if (walk->type >= XFRM_POLICY_TYPE_MAX && 892 walk->type != XFRM_POLICY_TYPE_ANY) 893 return -EINVAL; 894 895 if (list_empty(&walk->walk.all) && walk->seq != 0) 896 return 0; 897 898 write_lock_bh(&xfrm_policy_lock); 899 if (list_empty(&walk->walk.all)) 900 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 901 else 902 x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all); 903 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 904 if (x->dead) 905 continue; 906 pol = container_of(x, struct xfrm_policy, walk); 907 if (walk->type != XFRM_POLICY_TYPE_ANY && 908 walk->type != pol->type) 909 continue; 910 error = func(pol, xfrm_policy_id2dir(pol->index), 911 walk->seq, data); 912 if (error) { 913 list_move_tail(&walk->walk.all, &x->all); 914 goto out; 915 } 916 walk->seq++; 917 } 918 if (walk->seq == 0) { 919 error = -ENOENT; 920 goto out; 921 } 922 list_del_init(&walk->walk.all); 923 out: 924 write_unlock_bh(&xfrm_policy_lock); 925 return error; 926 } 927 EXPORT_SYMBOL(xfrm_policy_walk); 928 929 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 930 { 931 INIT_LIST_HEAD(&walk->walk.all); 932 walk->walk.dead = 1; 933 walk->type = type; 934 walk->seq = 0; 935 } 936 EXPORT_SYMBOL(xfrm_policy_walk_init); 937 938 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk) 939 { 940 if (list_empty(&walk->walk.all)) 941 return; 942 943 write_lock_bh(&xfrm_policy_lock); 944 list_del(&walk->walk.all); 945 write_unlock_bh(&xfrm_policy_lock); 946 } 947 EXPORT_SYMBOL(xfrm_policy_walk_done); 948 949 /* 950 * Find policy to apply to this flow. 951 * 952 * Returns 0 if policy found, else an -errno. 953 */ 954 static int xfrm_policy_match(const struct xfrm_policy *pol, 955 const struct flowi *fl, 956 u8 type, u16 family, int dir) 957 { 958 const struct xfrm_selector *sel = &pol->selector; 959 int ret = -ESRCH; 960 bool match; 961 962 if (pol->family != family || 963 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 964 pol->type != type) 965 return ret; 966 967 match = xfrm_selector_match(sel, fl, family); 968 if (match) 969 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 970 dir); 971 972 return ret; 973 } 974 975 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 976 const struct flowi *fl, 977 u16 family, u8 dir) 978 { 979 int err; 980 struct xfrm_policy *pol, *ret; 981 const xfrm_address_t *daddr, *saddr; 982 struct hlist_head *chain; 983 u32 priority = ~0U; 984 985 daddr = xfrm_flowi_daddr(fl, family); 986 saddr = xfrm_flowi_saddr(fl, family); 987 if (unlikely(!daddr || !saddr)) 988 return NULL; 989 990 read_lock_bh(&xfrm_policy_lock); 991 chain = policy_hash_direct(net, daddr, saddr, family, dir); 992 ret = NULL; 993 hlist_for_each_entry(pol, chain, bydst) { 994 err = xfrm_policy_match(pol, fl, type, family, dir); 995 if (err) { 996 if (err == -ESRCH) 997 continue; 998 else { 999 ret = ERR_PTR(err); 1000 goto fail; 1001 } 1002 } else { 1003 ret = pol; 1004 priority = ret->priority; 1005 break; 1006 } 1007 } 1008 chain = &net->xfrm.policy_inexact[dir]; 1009 hlist_for_each_entry(pol, chain, bydst) { 1010 err = xfrm_policy_match(pol, fl, type, family, dir); 1011 if (err) { 1012 if (err == -ESRCH) 1013 continue; 1014 else { 1015 ret = ERR_PTR(err); 1016 goto fail; 1017 } 1018 } else if (pol->priority < priority) { 1019 ret = pol; 1020 break; 1021 } 1022 } 1023 if (ret) 1024 xfrm_pol_hold(ret); 1025 fail: 1026 read_unlock_bh(&xfrm_policy_lock); 1027 1028 return ret; 1029 } 1030 1031 static struct xfrm_policy * 1032 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir) 1033 { 1034 #ifdef CONFIG_XFRM_SUB_POLICY 1035 struct xfrm_policy *pol; 1036 1037 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir); 1038 if (pol != NULL) 1039 return pol; 1040 #endif 1041 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir); 1042 } 1043 1044 static int flow_to_policy_dir(int dir) 1045 { 1046 if (XFRM_POLICY_IN == FLOW_DIR_IN && 1047 XFRM_POLICY_OUT == FLOW_DIR_OUT && 1048 XFRM_POLICY_FWD == FLOW_DIR_FWD) 1049 return dir; 1050 1051 switch (dir) { 1052 default: 1053 case FLOW_DIR_IN: 1054 return XFRM_POLICY_IN; 1055 case FLOW_DIR_OUT: 1056 return XFRM_POLICY_OUT; 1057 case FLOW_DIR_FWD: 1058 return XFRM_POLICY_FWD; 1059 } 1060 } 1061 1062 static struct flow_cache_object * 1063 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, 1064 u8 dir, struct flow_cache_object *old_obj, void *ctx) 1065 { 1066 struct xfrm_policy *pol; 1067 1068 if (old_obj) 1069 xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo)); 1070 1071 pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir)); 1072 if (IS_ERR_OR_NULL(pol)) 1073 return ERR_CAST(pol); 1074 1075 /* Resolver returns two references: 1076 * one for cache and one for caller of flow_cache_lookup() */ 1077 xfrm_pol_hold(pol); 1078 1079 return &pol->flo; 1080 } 1081 1082 static inline int policy_to_flow_dir(int dir) 1083 { 1084 if (XFRM_POLICY_IN == FLOW_DIR_IN && 1085 XFRM_POLICY_OUT == FLOW_DIR_OUT && 1086 XFRM_POLICY_FWD == FLOW_DIR_FWD) 1087 return dir; 1088 switch (dir) { 1089 default: 1090 case XFRM_POLICY_IN: 1091 return FLOW_DIR_IN; 1092 case XFRM_POLICY_OUT: 1093 return FLOW_DIR_OUT; 1094 case XFRM_POLICY_FWD: 1095 return FLOW_DIR_FWD; 1096 } 1097 } 1098 1099 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, 1100 const struct flowi *fl) 1101 { 1102 struct xfrm_policy *pol; 1103 1104 read_lock_bh(&xfrm_policy_lock); 1105 if ((pol = sk->sk_policy[dir]) != NULL) { 1106 bool match = xfrm_selector_match(&pol->selector, fl, 1107 sk->sk_family); 1108 int err = 0; 1109 1110 if (match) { 1111 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) { 1112 pol = NULL; 1113 goto out; 1114 } 1115 err = security_xfrm_policy_lookup(pol->security, 1116 fl->flowi_secid, 1117 policy_to_flow_dir(dir)); 1118 if (!err) 1119 xfrm_pol_hold(pol); 1120 else if (err == -ESRCH) 1121 pol = NULL; 1122 else 1123 pol = ERR_PTR(err); 1124 } else 1125 pol = NULL; 1126 } 1127 out: 1128 read_unlock_bh(&xfrm_policy_lock); 1129 return pol; 1130 } 1131 1132 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 1133 { 1134 struct net *net = xp_net(pol); 1135 struct hlist_head *chain = policy_hash_bysel(net, &pol->selector, 1136 pol->family, dir); 1137 1138 list_add(&pol->walk.all, &net->xfrm.policy_all); 1139 hlist_add_head(&pol->bydst, chain); 1140 hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index)); 1141 net->xfrm.policy_count[dir]++; 1142 xfrm_pol_hold(pol); 1143 1144 if (xfrm_bydst_should_resize(net, dir, NULL)) 1145 schedule_work(&net->xfrm.policy_hash_work); 1146 } 1147 1148 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 1149 int dir) 1150 { 1151 struct net *net = xp_net(pol); 1152 1153 if (hlist_unhashed(&pol->bydst)) 1154 return NULL; 1155 1156 hlist_del(&pol->bydst); 1157 hlist_del(&pol->byidx); 1158 list_del(&pol->walk.all); 1159 net->xfrm.policy_count[dir]--; 1160 1161 return pol; 1162 } 1163 1164 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 1165 { 1166 write_lock_bh(&xfrm_policy_lock); 1167 pol = __xfrm_policy_unlink(pol, dir); 1168 write_unlock_bh(&xfrm_policy_lock); 1169 if (pol) { 1170 xfrm_policy_kill(pol); 1171 return 0; 1172 } 1173 return -ENOENT; 1174 } 1175 EXPORT_SYMBOL(xfrm_policy_delete); 1176 1177 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 1178 { 1179 struct net *net = xp_net(pol); 1180 struct xfrm_policy *old_pol; 1181 1182 #ifdef CONFIG_XFRM_SUB_POLICY 1183 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 1184 return -EINVAL; 1185 #endif 1186 1187 write_lock_bh(&xfrm_policy_lock); 1188 old_pol = sk->sk_policy[dir]; 1189 sk->sk_policy[dir] = pol; 1190 if (pol) { 1191 pol->curlft.add_time = get_seconds(); 1192 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir); 1193 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir); 1194 } 1195 if (old_pol) { 1196 if (pol) 1197 xfrm_policy_requeue(old_pol, pol); 1198 1199 /* Unlinking succeeds always. This is the only function 1200 * allowed to delete or replace socket policy. 1201 */ 1202 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir); 1203 } 1204 write_unlock_bh(&xfrm_policy_lock); 1205 1206 if (old_pol) { 1207 xfrm_policy_kill(old_pol); 1208 } 1209 return 0; 1210 } 1211 1212 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 1213 { 1214 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 1215 1216 if (newp) { 1217 newp->selector = old->selector; 1218 if (security_xfrm_policy_clone(old->security, 1219 &newp->security)) { 1220 kfree(newp); 1221 return NULL; /* ENOMEM */ 1222 } 1223 newp->lft = old->lft; 1224 newp->curlft = old->curlft; 1225 newp->mark = old->mark; 1226 newp->action = old->action; 1227 newp->flags = old->flags; 1228 newp->xfrm_nr = old->xfrm_nr; 1229 newp->index = old->index; 1230 newp->type = old->type; 1231 memcpy(newp->xfrm_vec, old->xfrm_vec, 1232 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 1233 write_lock_bh(&xfrm_policy_lock); 1234 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir); 1235 write_unlock_bh(&xfrm_policy_lock); 1236 xfrm_pol_put(newp); 1237 } 1238 return newp; 1239 } 1240 1241 int __xfrm_sk_clone_policy(struct sock *sk) 1242 { 1243 struct xfrm_policy *p0 = sk->sk_policy[0], 1244 *p1 = sk->sk_policy[1]; 1245 1246 sk->sk_policy[0] = sk->sk_policy[1] = NULL; 1247 if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL) 1248 return -ENOMEM; 1249 if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL) 1250 return -ENOMEM; 1251 return 0; 1252 } 1253 1254 static int 1255 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote, 1256 unsigned short family) 1257 { 1258 int err; 1259 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1260 1261 if (unlikely(afinfo == NULL)) 1262 return -EINVAL; 1263 err = afinfo->get_saddr(net, local, remote); 1264 xfrm_policy_put_afinfo(afinfo); 1265 return err; 1266 } 1267 1268 /* Resolve list of templates for the flow, given policy. */ 1269 1270 static int 1271 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 1272 struct xfrm_state **xfrm, unsigned short family) 1273 { 1274 struct net *net = xp_net(policy); 1275 int nx; 1276 int i, error; 1277 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 1278 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 1279 xfrm_address_t tmp; 1280 1281 for (nx=0, i = 0; i < policy->xfrm_nr; i++) { 1282 struct xfrm_state *x; 1283 xfrm_address_t *remote = daddr; 1284 xfrm_address_t *local = saddr; 1285 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 1286 1287 if (tmpl->mode == XFRM_MODE_TUNNEL || 1288 tmpl->mode == XFRM_MODE_BEET) { 1289 remote = &tmpl->id.daddr; 1290 local = &tmpl->saddr; 1291 if (xfrm_addr_any(local, tmpl->encap_family)) { 1292 error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family); 1293 if (error) 1294 goto fail; 1295 local = &tmp; 1296 } 1297 } 1298 1299 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); 1300 1301 if (x && x->km.state == XFRM_STATE_VALID) { 1302 xfrm[nx++] = x; 1303 daddr = remote; 1304 saddr = local; 1305 continue; 1306 } 1307 if (x) { 1308 error = (x->km.state == XFRM_STATE_ERROR ? 1309 -EINVAL : -EAGAIN); 1310 xfrm_state_put(x); 1311 } 1312 else if (error == -ESRCH) 1313 error = -EAGAIN; 1314 1315 if (!tmpl->optional) 1316 goto fail; 1317 } 1318 return nx; 1319 1320 fail: 1321 for (nx--; nx>=0; nx--) 1322 xfrm_state_put(xfrm[nx]); 1323 return error; 1324 } 1325 1326 static int 1327 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 1328 struct xfrm_state **xfrm, unsigned short family) 1329 { 1330 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 1331 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 1332 int cnx = 0; 1333 int error; 1334 int ret; 1335 int i; 1336 1337 for (i = 0; i < npols; i++) { 1338 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 1339 error = -ENOBUFS; 1340 goto fail; 1341 } 1342 1343 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 1344 if (ret < 0) { 1345 error = ret; 1346 goto fail; 1347 } else 1348 cnx += ret; 1349 } 1350 1351 /* found states are sorted for outbound processing */ 1352 if (npols > 1) 1353 xfrm_state_sort(xfrm, tpp, cnx, family); 1354 1355 return cnx; 1356 1357 fail: 1358 for (cnx--; cnx>=0; cnx--) 1359 xfrm_state_put(tpp[cnx]); 1360 return error; 1361 1362 } 1363 1364 /* Check that the bundle accepts the flow and its components are 1365 * still valid. 1366 */ 1367 1368 static inline int xfrm_get_tos(const struct flowi *fl, int family) 1369 { 1370 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1371 int tos; 1372 1373 if (!afinfo) 1374 return -EINVAL; 1375 1376 tos = afinfo->get_tos(fl); 1377 1378 xfrm_policy_put_afinfo(afinfo); 1379 1380 return tos; 1381 } 1382 1383 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo) 1384 { 1385 struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo); 1386 struct dst_entry *dst = &xdst->u.dst; 1387 1388 if (xdst->route == NULL) { 1389 /* Dummy bundle - if it has xfrms we were not 1390 * able to build bundle as template resolution failed. 1391 * It means we need to try again resolving. */ 1392 if (xdst->num_xfrms > 0) 1393 return NULL; 1394 } else if (dst->flags & DST_XFRM_QUEUE) { 1395 return NULL; 1396 } else { 1397 /* Real bundle */ 1398 if (stale_bundle(dst)) 1399 return NULL; 1400 } 1401 1402 dst_hold(dst); 1403 return flo; 1404 } 1405 1406 static int xfrm_bundle_flo_check(struct flow_cache_object *flo) 1407 { 1408 struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo); 1409 struct dst_entry *dst = &xdst->u.dst; 1410 1411 if (!xdst->route) 1412 return 0; 1413 if (stale_bundle(dst)) 1414 return 0; 1415 1416 return 1; 1417 } 1418 1419 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo) 1420 { 1421 struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo); 1422 struct dst_entry *dst = &xdst->u.dst; 1423 1424 dst_free(dst); 1425 } 1426 1427 static const struct flow_cache_ops xfrm_bundle_fc_ops = { 1428 .get = xfrm_bundle_flo_get, 1429 .check = xfrm_bundle_flo_check, 1430 .delete = xfrm_bundle_flo_delete, 1431 }; 1432 1433 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 1434 { 1435 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1436 struct dst_ops *dst_ops; 1437 struct xfrm_dst *xdst; 1438 1439 if (!afinfo) 1440 return ERR_PTR(-EINVAL); 1441 1442 switch (family) { 1443 case AF_INET: 1444 dst_ops = &net->xfrm.xfrm4_dst_ops; 1445 break; 1446 #if IS_ENABLED(CONFIG_IPV6) 1447 case AF_INET6: 1448 dst_ops = &net->xfrm.xfrm6_dst_ops; 1449 break; 1450 #endif 1451 default: 1452 BUG(); 1453 } 1454 xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0); 1455 1456 if (likely(xdst)) { 1457 struct dst_entry *dst = &xdst->u.dst; 1458 1459 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 1460 xdst->flo.ops = &xfrm_bundle_fc_ops; 1461 if (afinfo->init_dst) 1462 afinfo->init_dst(net, xdst); 1463 } else 1464 xdst = ERR_PTR(-ENOBUFS); 1465 1466 xfrm_policy_put_afinfo(afinfo); 1467 1468 return xdst; 1469 } 1470 1471 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 1472 int nfheader_len) 1473 { 1474 struct xfrm_policy_afinfo *afinfo = 1475 xfrm_policy_get_afinfo(dst->ops->family); 1476 int err; 1477 1478 if (!afinfo) 1479 return -EINVAL; 1480 1481 err = afinfo->init_path(path, dst, nfheader_len); 1482 1483 xfrm_policy_put_afinfo(afinfo); 1484 1485 return err; 1486 } 1487 1488 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 1489 const struct flowi *fl) 1490 { 1491 struct xfrm_policy_afinfo *afinfo = 1492 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 1493 int err; 1494 1495 if (!afinfo) 1496 return -EINVAL; 1497 1498 err = afinfo->fill_dst(xdst, dev, fl); 1499 1500 xfrm_policy_put_afinfo(afinfo); 1501 1502 return err; 1503 } 1504 1505 1506 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 1507 * all the metrics... Shortly, bundle a bundle. 1508 */ 1509 1510 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 1511 struct xfrm_state **xfrm, int nx, 1512 const struct flowi *fl, 1513 struct dst_entry *dst) 1514 { 1515 struct net *net = xp_net(policy); 1516 unsigned long now = jiffies; 1517 struct net_device *dev; 1518 struct xfrm_mode *inner_mode; 1519 struct dst_entry *dst_prev = NULL; 1520 struct dst_entry *dst0 = NULL; 1521 int i = 0; 1522 int err; 1523 int header_len = 0; 1524 int nfheader_len = 0; 1525 int trailer_len = 0; 1526 int tos; 1527 int family = policy->selector.family; 1528 xfrm_address_t saddr, daddr; 1529 1530 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 1531 1532 tos = xfrm_get_tos(fl, family); 1533 err = tos; 1534 if (tos < 0) 1535 goto put_states; 1536 1537 dst_hold(dst); 1538 1539 for (; i < nx; i++) { 1540 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 1541 struct dst_entry *dst1 = &xdst->u.dst; 1542 1543 err = PTR_ERR(xdst); 1544 if (IS_ERR(xdst)) { 1545 dst_release(dst); 1546 goto put_states; 1547 } 1548 1549 if (xfrm[i]->sel.family == AF_UNSPEC) { 1550 inner_mode = xfrm_ip2inner_mode(xfrm[i], 1551 xfrm_af2proto(family)); 1552 if (!inner_mode) { 1553 err = -EAFNOSUPPORT; 1554 dst_release(dst); 1555 goto put_states; 1556 } 1557 } else 1558 inner_mode = xfrm[i]->inner_mode; 1559 1560 if (!dst_prev) 1561 dst0 = dst1; 1562 else { 1563 dst_prev->child = dst_clone(dst1); 1564 dst1->flags |= DST_NOHASH; 1565 } 1566 1567 xdst->route = dst; 1568 dst_copy_metrics(dst1, dst); 1569 1570 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 1571 family = xfrm[i]->props.family; 1572 dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr, 1573 family); 1574 err = PTR_ERR(dst); 1575 if (IS_ERR(dst)) 1576 goto put_states; 1577 } else 1578 dst_hold(dst); 1579 1580 dst1->xfrm = xfrm[i]; 1581 xdst->xfrm_genid = xfrm[i]->genid; 1582 1583 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1584 dst1->flags |= DST_HOST; 1585 dst1->lastuse = now; 1586 1587 dst1->input = dst_discard; 1588 dst1->output = inner_mode->afinfo->output; 1589 1590 dst1->next = dst_prev; 1591 dst_prev = dst1; 1592 1593 header_len += xfrm[i]->props.header_len; 1594 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 1595 nfheader_len += xfrm[i]->props.header_len; 1596 trailer_len += xfrm[i]->props.trailer_len; 1597 } 1598 1599 dst_prev->child = dst; 1600 dst0->path = dst; 1601 1602 err = -ENODEV; 1603 dev = dst->dev; 1604 if (!dev) 1605 goto free_dst; 1606 1607 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len); 1608 xfrm_init_pmtu(dst_prev); 1609 1610 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) { 1611 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev; 1612 1613 err = xfrm_fill_dst(xdst, dev, fl); 1614 if (err) 1615 goto free_dst; 1616 1617 dst_prev->header_len = header_len; 1618 dst_prev->trailer_len = trailer_len; 1619 header_len -= xdst->u.dst.xfrm->props.header_len; 1620 trailer_len -= xdst->u.dst.xfrm->props.trailer_len; 1621 } 1622 1623 out: 1624 return dst0; 1625 1626 put_states: 1627 for (; i < nx; i++) 1628 xfrm_state_put(xfrm[i]); 1629 free_dst: 1630 if (dst0) 1631 dst_free(dst0); 1632 dst0 = ERR_PTR(err); 1633 goto out; 1634 } 1635 1636 static int inline 1637 xfrm_dst_alloc_copy(void **target, const void *src, int size) 1638 { 1639 if (!*target) { 1640 *target = kmalloc(size, GFP_ATOMIC); 1641 if (!*target) 1642 return -ENOMEM; 1643 } 1644 memcpy(*target, src, size); 1645 return 0; 1646 } 1647 1648 static int inline 1649 xfrm_dst_update_parent(struct dst_entry *dst, const struct xfrm_selector *sel) 1650 { 1651 #ifdef CONFIG_XFRM_SUB_POLICY 1652 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 1653 return xfrm_dst_alloc_copy((void **)&(xdst->partner), 1654 sel, sizeof(*sel)); 1655 #else 1656 return 0; 1657 #endif 1658 } 1659 1660 static int inline 1661 xfrm_dst_update_origin(struct dst_entry *dst, const struct flowi *fl) 1662 { 1663 #ifdef CONFIG_XFRM_SUB_POLICY 1664 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 1665 return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl)); 1666 #else 1667 return 0; 1668 #endif 1669 } 1670 1671 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 1672 struct xfrm_policy **pols, 1673 int *num_pols, int *num_xfrms) 1674 { 1675 int i; 1676 1677 if (*num_pols == 0 || !pols[0]) { 1678 *num_pols = 0; 1679 *num_xfrms = 0; 1680 return 0; 1681 } 1682 if (IS_ERR(pols[0])) 1683 return PTR_ERR(pols[0]); 1684 1685 *num_xfrms = pols[0]->xfrm_nr; 1686 1687 #ifdef CONFIG_XFRM_SUB_POLICY 1688 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 1689 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 1690 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 1691 XFRM_POLICY_TYPE_MAIN, 1692 fl, family, 1693 XFRM_POLICY_OUT); 1694 if (pols[1]) { 1695 if (IS_ERR(pols[1])) { 1696 xfrm_pols_put(pols, *num_pols); 1697 return PTR_ERR(pols[1]); 1698 } 1699 (*num_pols) ++; 1700 (*num_xfrms) += pols[1]->xfrm_nr; 1701 } 1702 } 1703 #endif 1704 for (i = 0; i < *num_pols; i++) { 1705 if (pols[i]->action != XFRM_POLICY_ALLOW) { 1706 *num_xfrms = -1; 1707 break; 1708 } 1709 } 1710 1711 return 0; 1712 1713 } 1714 1715 static struct xfrm_dst * 1716 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 1717 const struct flowi *fl, u16 family, 1718 struct dst_entry *dst_orig) 1719 { 1720 struct net *net = xp_net(pols[0]); 1721 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 1722 struct dst_entry *dst; 1723 struct xfrm_dst *xdst; 1724 int err; 1725 1726 /* Try to instantiate a bundle */ 1727 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 1728 if (err <= 0) { 1729 if (err != 0 && err != -EAGAIN) 1730 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 1731 return ERR_PTR(err); 1732 } 1733 1734 dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig); 1735 if (IS_ERR(dst)) { 1736 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 1737 return ERR_CAST(dst); 1738 } 1739 1740 xdst = (struct xfrm_dst *)dst; 1741 xdst->num_xfrms = err; 1742 if (num_pols > 1) 1743 err = xfrm_dst_update_parent(dst, &pols[1]->selector); 1744 else 1745 err = xfrm_dst_update_origin(dst, fl); 1746 if (unlikely(err)) { 1747 dst_free(dst); 1748 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR); 1749 return ERR_PTR(err); 1750 } 1751 1752 xdst->num_pols = num_pols; 1753 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols); 1754 xdst->policy_genid = atomic_read(&pols[0]->genid); 1755 1756 return xdst; 1757 } 1758 1759 static void xfrm_policy_queue_process(unsigned long arg) 1760 { 1761 int err = 0; 1762 struct sk_buff *skb; 1763 struct sock *sk; 1764 struct dst_entry *dst; 1765 struct xfrm_policy *pol = (struct xfrm_policy *)arg; 1766 struct xfrm_policy_queue *pq = &pol->polq; 1767 struct flowi fl; 1768 struct sk_buff_head list; 1769 1770 spin_lock(&pq->hold_queue.lock); 1771 skb = skb_peek(&pq->hold_queue); 1772 dst = skb_dst(skb); 1773 sk = skb->sk; 1774 xfrm_decode_session(skb, &fl, dst->ops->family); 1775 spin_unlock(&pq->hold_queue.lock); 1776 1777 dst_hold(dst->path); 1778 dst = xfrm_lookup(xp_net(pol), dst->path, &fl, 1779 sk, 0); 1780 if (IS_ERR(dst)) 1781 goto purge_queue; 1782 1783 if (dst->flags & DST_XFRM_QUEUE) { 1784 dst_release(dst); 1785 1786 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 1787 goto purge_queue; 1788 1789 pq->timeout = pq->timeout << 1; 1790 mod_timer(&pq->hold_timer, jiffies + pq->timeout); 1791 return; 1792 } 1793 1794 dst_release(dst); 1795 1796 __skb_queue_head_init(&list); 1797 1798 spin_lock(&pq->hold_queue.lock); 1799 pq->timeout = 0; 1800 skb_queue_splice_init(&pq->hold_queue, &list); 1801 spin_unlock(&pq->hold_queue.lock); 1802 1803 while (!skb_queue_empty(&list)) { 1804 skb = __skb_dequeue(&list); 1805 1806 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 1807 dst_hold(skb_dst(skb)->path); 1808 dst = xfrm_lookup(xp_net(pol), skb_dst(skb)->path, 1809 &fl, skb->sk, 0); 1810 if (IS_ERR(dst)) { 1811 kfree_skb(skb); 1812 continue; 1813 } 1814 1815 nf_reset(skb); 1816 skb_dst_drop(skb); 1817 skb_dst_set(skb, dst); 1818 1819 err = dst_output(skb); 1820 } 1821 1822 return; 1823 1824 purge_queue: 1825 pq->timeout = 0; 1826 xfrm_queue_purge(&pq->hold_queue); 1827 } 1828 1829 static int xdst_queue_output(struct sk_buff *skb) 1830 { 1831 unsigned long sched_next; 1832 struct dst_entry *dst = skb_dst(skb); 1833 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 1834 struct xfrm_policy_queue *pq = &xdst->pols[0]->polq; 1835 1836 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 1837 kfree_skb(skb); 1838 return -EAGAIN; 1839 } 1840 1841 skb_dst_force(skb); 1842 1843 spin_lock_bh(&pq->hold_queue.lock); 1844 1845 if (!pq->timeout) 1846 pq->timeout = XFRM_QUEUE_TMO_MIN; 1847 1848 sched_next = jiffies + pq->timeout; 1849 1850 if (del_timer(&pq->hold_timer)) { 1851 if (time_before(pq->hold_timer.expires, sched_next)) 1852 sched_next = pq->hold_timer.expires; 1853 } 1854 1855 __skb_queue_tail(&pq->hold_queue, skb); 1856 mod_timer(&pq->hold_timer, sched_next); 1857 1858 spin_unlock_bh(&pq->hold_queue.lock); 1859 1860 return 0; 1861 } 1862 1863 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 1864 struct dst_entry *dst, 1865 const struct flowi *fl, 1866 int num_xfrms, 1867 u16 family) 1868 { 1869 int err; 1870 struct net_device *dev; 1871 struct dst_entry *dst1; 1872 struct xfrm_dst *xdst; 1873 1874 xdst = xfrm_alloc_dst(net, family); 1875 if (IS_ERR(xdst)) 1876 return xdst; 1877 1878 if (net->xfrm.sysctl_larval_drop || num_xfrms <= 0 || 1879 (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP)) 1880 return xdst; 1881 1882 dst1 = &xdst->u.dst; 1883 dst_hold(dst); 1884 xdst->route = dst; 1885 1886 dst_copy_metrics(dst1, dst); 1887 1888 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1889 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 1890 dst1->lastuse = jiffies; 1891 1892 dst1->input = dst_discard; 1893 dst1->output = xdst_queue_output; 1894 1895 dst_hold(dst); 1896 dst1->child = dst; 1897 dst1->path = dst; 1898 1899 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 1900 1901 err = -ENODEV; 1902 dev = dst->dev; 1903 if (!dev) 1904 goto free_dst; 1905 1906 err = xfrm_fill_dst(xdst, dev, fl); 1907 if (err) 1908 goto free_dst; 1909 1910 out: 1911 return xdst; 1912 1913 free_dst: 1914 dst_release(dst1); 1915 xdst = ERR_PTR(err); 1916 goto out; 1917 } 1918 1919 static struct flow_cache_object * 1920 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, 1921 struct flow_cache_object *oldflo, void *ctx) 1922 { 1923 struct dst_entry *dst_orig = (struct dst_entry *)ctx; 1924 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 1925 struct xfrm_dst *xdst, *new_xdst; 1926 int num_pols = 0, num_xfrms = 0, i, err, pol_dead; 1927 1928 /* Check if the policies from old bundle are usable */ 1929 xdst = NULL; 1930 if (oldflo) { 1931 xdst = container_of(oldflo, struct xfrm_dst, flo); 1932 num_pols = xdst->num_pols; 1933 num_xfrms = xdst->num_xfrms; 1934 pol_dead = 0; 1935 for (i = 0; i < num_pols; i++) { 1936 pols[i] = xdst->pols[i]; 1937 pol_dead |= pols[i]->walk.dead; 1938 } 1939 if (pol_dead) { 1940 dst_free(&xdst->u.dst); 1941 xdst = NULL; 1942 num_pols = 0; 1943 num_xfrms = 0; 1944 oldflo = NULL; 1945 } 1946 } 1947 1948 /* Resolve policies to use if we couldn't get them from 1949 * previous cache entry */ 1950 if (xdst == NULL) { 1951 num_pols = 1; 1952 pols[0] = __xfrm_policy_lookup(net, fl, family, 1953 flow_to_policy_dir(dir)); 1954 err = xfrm_expand_policies(fl, family, pols, 1955 &num_pols, &num_xfrms); 1956 if (err < 0) 1957 goto inc_error; 1958 if (num_pols == 0) 1959 return NULL; 1960 if (num_xfrms <= 0) 1961 goto make_dummy_bundle; 1962 } 1963 1964 new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, dst_orig); 1965 if (IS_ERR(new_xdst)) { 1966 err = PTR_ERR(new_xdst); 1967 if (err != -EAGAIN) 1968 goto error; 1969 if (oldflo == NULL) 1970 goto make_dummy_bundle; 1971 dst_hold(&xdst->u.dst); 1972 return oldflo; 1973 } else if (new_xdst == NULL) { 1974 num_xfrms = 0; 1975 if (oldflo == NULL) 1976 goto make_dummy_bundle; 1977 xdst->num_xfrms = 0; 1978 dst_hold(&xdst->u.dst); 1979 return oldflo; 1980 } 1981 1982 /* Kill the previous bundle */ 1983 if (xdst) { 1984 /* The policies were stolen for newly generated bundle */ 1985 xdst->num_pols = 0; 1986 dst_free(&xdst->u.dst); 1987 } 1988 1989 /* Flow cache does not have reference, it dst_free()'s, 1990 * but we do need to return one reference for original caller */ 1991 dst_hold(&new_xdst->u.dst); 1992 return &new_xdst->flo; 1993 1994 make_dummy_bundle: 1995 /* We found policies, but there's no bundles to instantiate: 1996 * either because the policy blocks, has no transformations or 1997 * we could not build template (no xfrm_states).*/ 1998 xdst = xfrm_create_dummy_bundle(net, dst_orig, fl, num_xfrms, family); 1999 if (IS_ERR(xdst)) { 2000 xfrm_pols_put(pols, num_pols); 2001 return ERR_CAST(xdst); 2002 } 2003 xdst->num_pols = num_pols; 2004 xdst->num_xfrms = num_xfrms; 2005 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols); 2006 2007 dst_hold(&xdst->u.dst); 2008 return &xdst->flo; 2009 2010 inc_error: 2011 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2012 error: 2013 if (xdst != NULL) 2014 dst_free(&xdst->u.dst); 2015 else 2016 xfrm_pols_put(pols, num_pols); 2017 return ERR_PTR(err); 2018 } 2019 2020 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2021 struct dst_entry *dst_orig) 2022 { 2023 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2024 struct dst_entry *ret; 2025 2026 if (!afinfo) { 2027 dst_release(dst_orig); 2028 return ERR_PTR(-EINVAL); 2029 } else { 2030 ret = afinfo->blackhole_route(net, dst_orig); 2031 } 2032 xfrm_policy_put_afinfo(afinfo); 2033 2034 return ret; 2035 } 2036 2037 /* Main function: finds/creates a bundle for given flow. 2038 * 2039 * At the moment we eat a raw IP route. Mostly to speed up lookups 2040 * on interfaces with disabled IPsec. 2041 */ 2042 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 2043 const struct flowi *fl, 2044 struct sock *sk, int flags) 2045 { 2046 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2047 struct flow_cache_object *flo; 2048 struct xfrm_dst *xdst; 2049 struct dst_entry *dst, *route; 2050 u16 family = dst_orig->ops->family; 2051 u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT); 2052 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 2053 2054 restart: 2055 dst = NULL; 2056 xdst = NULL; 2057 route = NULL; 2058 2059 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 2060 num_pols = 1; 2061 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl); 2062 err = xfrm_expand_policies(fl, family, pols, 2063 &num_pols, &num_xfrms); 2064 if (err < 0) 2065 goto dropdst; 2066 2067 if (num_pols) { 2068 if (num_xfrms <= 0) { 2069 drop_pols = num_pols; 2070 goto no_transform; 2071 } 2072 2073 xdst = xfrm_resolve_and_create_bundle( 2074 pols, num_pols, fl, 2075 family, dst_orig); 2076 if (IS_ERR(xdst)) { 2077 xfrm_pols_put(pols, num_pols); 2078 err = PTR_ERR(xdst); 2079 goto dropdst; 2080 } else if (xdst == NULL) { 2081 num_xfrms = 0; 2082 drop_pols = num_pols; 2083 goto no_transform; 2084 } 2085 2086 dst_hold(&xdst->u.dst); 2087 2088 spin_lock_bh(&xfrm_policy_sk_bundle_lock); 2089 xdst->u.dst.next = xfrm_policy_sk_bundles; 2090 xfrm_policy_sk_bundles = &xdst->u.dst; 2091 spin_unlock_bh(&xfrm_policy_sk_bundle_lock); 2092 2093 route = xdst->route; 2094 } 2095 } 2096 2097 if (xdst == NULL) { 2098 /* To accelerate a bit... */ 2099 if ((dst_orig->flags & DST_NOXFRM) || 2100 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 2101 goto nopol; 2102 2103 flo = flow_cache_lookup(net, fl, family, dir, 2104 xfrm_bundle_lookup, dst_orig); 2105 if (flo == NULL) 2106 goto nopol; 2107 if (IS_ERR(flo)) { 2108 err = PTR_ERR(flo); 2109 goto dropdst; 2110 } 2111 xdst = container_of(flo, struct xfrm_dst, flo); 2112 2113 num_pols = xdst->num_pols; 2114 num_xfrms = xdst->num_xfrms; 2115 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy*) * num_pols); 2116 route = xdst->route; 2117 } 2118 2119 dst = &xdst->u.dst; 2120 if (route == NULL && num_xfrms > 0) { 2121 /* The only case when xfrm_bundle_lookup() returns a 2122 * bundle with null route, is when the template could 2123 * not be resolved. It means policies are there, but 2124 * bundle could not be created, since we don't yet 2125 * have the xfrm_state's. We need to wait for KM to 2126 * negotiate new SA's or bail out with error.*/ 2127 if (net->xfrm.sysctl_larval_drop) { 2128 dst_release(dst); 2129 xfrm_pols_put(pols, drop_pols); 2130 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2131 2132 return make_blackhole(net, family, dst_orig); 2133 } 2134 if (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP) { 2135 DECLARE_WAITQUEUE(wait, current); 2136 2137 add_wait_queue(&net->xfrm.km_waitq, &wait); 2138 set_current_state(TASK_INTERRUPTIBLE); 2139 schedule(); 2140 set_current_state(TASK_RUNNING); 2141 remove_wait_queue(&net->xfrm.km_waitq, &wait); 2142 2143 if (!signal_pending(current)) { 2144 dst_release(dst); 2145 goto restart; 2146 } 2147 2148 err = -ERESTART; 2149 } else 2150 err = -EAGAIN; 2151 2152 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2153 goto error; 2154 } 2155 2156 no_transform: 2157 if (num_pols == 0) 2158 goto nopol; 2159 2160 if ((flags & XFRM_LOOKUP_ICMP) && 2161 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 2162 err = -ENOENT; 2163 goto error; 2164 } 2165 2166 for (i = 0; i < num_pols; i++) 2167 pols[i]->curlft.use_time = get_seconds(); 2168 2169 if (num_xfrms < 0) { 2170 /* Prohibit the flow */ 2171 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 2172 err = -EPERM; 2173 goto error; 2174 } else if (num_xfrms > 0) { 2175 /* Flow transformed */ 2176 dst_release(dst_orig); 2177 } else { 2178 /* Flow passes untransformed */ 2179 dst_release(dst); 2180 dst = dst_orig; 2181 } 2182 ok: 2183 xfrm_pols_put(pols, drop_pols); 2184 if (dst && dst->xfrm && 2185 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 2186 dst->flags |= DST_XFRM_TUNNEL; 2187 return dst; 2188 2189 nopol: 2190 if (!(flags & XFRM_LOOKUP_ICMP)) { 2191 dst = dst_orig; 2192 goto ok; 2193 } 2194 err = -ENOENT; 2195 error: 2196 dst_release(dst); 2197 dropdst: 2198 dst_release(dst_orig); 2199 xfrm_pols_put(pols, drop_pols); 2200 return ERR_PTR(err); 2201 } 2202 EXPORT_SYMBOL(xfrm_lookup); 2203 2204 static inline int 2205 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 2206 { 2207 struct xfrm_state *x; 2208 2209 if (!skb->sp || idx < 0 || idx >= skb->sp->len) 2210 return 0; 2211 x = skb->sp->xvec[idx]; 2212 if (!x->type->reject) 2213 return 0; 2214 return x->type->reject(x, skb, fl); 2215 } 2216 2217 /* When skb is transformed back to its "native" form, we have to 2218 * check policy restrictions. At the moment we make this in maximally 2219 * stupid way. Shame on me. :-) Of course, connected sockets must 2220 * have policy cached at them. 2221 */ 2222 2223 static inline int 2224 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 2225 unsigned short family) 2226 { 2227 if (xfrm_state_kern(x)) 2228 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 2229 return x->id.proto == tmpl->id.proto && 2230 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 2231 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 2232 x->props.mode == tmpl->mode && 2233 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 2234 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 2235 !(x->props.mode != XFRM_MODE_TRANSPORT && 2236 xfrm_state_addr_cmp(tmpl, x, family)); 2237 } 2238 2239 /* 2240 * 0 or more than 0 is returned when validation is succeeded (either bypass 2241 * because of optional transport mode, or next index of the mathced secpath 2242 * state with the template. 2243 * -1 is returned when no matching template is found. 2244 * Otherwise "-2 - errored_index" is returned. 2245 */ 2246 static inline int 2247 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 2248 unsigned short family) 2249 { 2250 int idx = start; 2251 2252 if (tmpl->optional) { 2253 if (tmpl->mode == XFRM_MODE_TRANSPORT) 2254 return start; 2255 } else 2256 start = -1; 2257 for (; idx < sp->len; idx++) { 2258 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 2259 return ++idx; 2260 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 2261 if (start == -1) 2262 start = -2-idx; 2263 break; 2264 } 2265 } 2266 return start; 2267 } 2268 2269 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 2270 unsigned int family, int reverse) 2271 { 2272 struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2273 int err; 2274 2275 if (unlikely(afinfo == NULL)) 2276 return -EAFNOSUPPORT; 2277 2278 afinfo->decode_session(skb, fl, reverse); 2279 err = security_xfrm_decode_session(skb, &fl->flowi_secid); 2280 xfrm_policy_put_afinfo(afinfo); 2281 return err; 2282 } 2283 EXPORT_SYMBOL(__xfrm_decode_session); 2284 2285 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 2286 { 2287 for (; k < sp->len; k++) { 2288 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 2289 *idxp = k; 2290 return 1; 2291 } 2292 } 2293 2294 return 0; 2295 } 2296 2297 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 2298 unsigned short family) 2299 { 2300 struct net *net = dev_net(skb->dev); 2301 struct xfrm_policy *pol; 2302 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2303 int npols = 0; 2304 int xfrm_nr; 2305 int pi; 2306 int reverse; 2307 struct flowi fl; 2308 u8 fl_dir; 2309 int xerr_idx = -1; 2310 2311 reverse = dir & ~XFRM_POLICY_MASK; 2312 dir &= XFRM_POLICY_MASK; 2313 fl_dir = policy_to_flow_dir(dir); 2314 2315 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 2316 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 2317 return 0; 2318 } 2319 2320 nf_nat_decode_session(skb, &fl, family); 2321 2322 /* First, check used SA against their selectors. */ 2323 if (skb->sp) { 2324 int i; 2325 2326 for (i=skb->sp->len-1; i>=0; i--) { 2327 struct xfrm_state *x = skb->sp->xvec[i]; 2328 if (!xfrm_selector_match(&x->sel, &fl, family)) { 2329 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 2330 return 0; 2331 } 2332 } 2333 } 2334 2335 pol = NULL; 2336 if (sk && sk->sk_policy[dir]) { 2337 pol = xfrm_sk_policy_lookup(sk, dir, &fl); 2338 if (IS_ERR(pol)) { 2339 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2340 return 0; 2341 } 2342 } 2343 2344 if (!pol) { 2345 struct flow_cache_object *flo; 2346 2347 flo = flow_cache_lookup(net, &fl, family, fl_dir, 2348 xfrm_policy_lookup, NULL); 2349 if (IS_ERR_OR_NULL(flo)) 2350 pol = ERR_CAST(flo); 2351 else 2352 pol = container_of(flo, struct xfrm_policy, flo); 2353 } 2354 2355 if (IS_ERR(pol)) { 2356 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2357 return 0; 2358 } 2359 2360 if (!pol) { 2361 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) { 2362 xfrm_secpath_reject(xerr_idx, skb, &fl); 2363 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 2364 return 0; 2365 } 2366 return 1; 2367 } 2368 2369 pol->curlft.use_time = get_seconds(); 2370 2371 pols[0] = pol; 2372 npols ++; 2373 #ifdef CONFIG_XFRM_SUB_POLICY 2374 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2375 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 2376 &fl, family, 2377 XFRM_POLICY_IN); 2378 if (pols[1]) { 2379 if (IS_ERR(pols[1])) { 2380 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2381 return 0; 2382 } 2383 pols[1]->curlft.use_time = get_seconds(); 2384 npols ++; 2385 } 2386 } 2387 #endif 2388 2389 if (pol->action == XFRM_POLICY_ALLOW) { 2390 struct sec_path *sp; 2391 static struct sec_path dummy; 2392 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 2393 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 2394 struct xfrm_tmpl **tpp = tp; 2395 int ti = 0; 2396 int i, k; 2397 2398 if ((sp = skb->sp) == NULL) 2399 sp = &dummy; 2400 2401 for (pi = 0; pi < npols; pi++) { 2402 if (pols[pi] != pol && 2403 pols[pi]->action != XFRM_POLICY_ALLOW) { 2404 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2405 goto reject; 2406 } 2407 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 2408 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 2409 goto reject_error; 2410 } 2411 for (i = 0; i < pols[pi]->xfrm_nr; i++) 2412 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 2413 } 2414 xfrm_nr = ti; 2415 if (npols > 1) { 2416 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family); 2417 tpp = stp; 2418 } 2419 2420 /* For each tunnel xfrm, find the first matching tmpl. 2421 * For each tmpl before that, find corresponding xfrm. 2422 * Order is _important_. Later we will implement 2423 * some barriers, but at the moment barriers 2424 * are implied between each two transformations. 2425 */ 2426 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 2427 k = xfrm_policy_ok(tpp[i], sp, k, family); 2428 if (k < 0) { 2429 if (k < -1) 2430 /* "-2 - errored_index" returned */ 2431 xerr_idx = -(2+k); 2432 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2433 goto reject; 2434 } 2435 } 2436 2437 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 2438 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2439 goto reject; 2440 } 2441 2442 xfrm_pols_put(pols, npols); 2443 return 1; 2444 } 2445 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2446 2447 reject: 2448 xfrm_secpath_reject(xerr_idx, skb, &fl); 2449 reject_error: 2450 xfrm_pols_put(pols, npols); 2451 return 0; 2452 } 2453 EXPORT_SYMBOL(__xfrm_policy_check); 2454 2455 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 2456 { 2457 struct net *net = dev_net(skb->dev); 2458 struct flowi fl; 2459 struct dst_entry *dst; 2460 int res = 1; 2461 2462 if (xfrm_decode_session(skb, &fl, family) < 0) { 2463 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2464 return 0; 2465 } 2466 2467 skb_dst_force(skb); 2468 2469 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, 0); 2470 if (IS_ERR(dst)) { 2471 res = 0; 2472 dst = NULL; 2473 } 2474 skb_dst_set(skb, dst); 2475 return res; 2476 } 2477 EXPORT_SYMBOL(__xfrm_route_forward); 2478 2479 /* Optimize later using cookies and generation ids. */ 2480 2481 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 2482 { 2483 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 2484 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 2485 * get validated by dst_ops->check on every use. We do this 2486 * because when a normal route referenced by an XFRM dst is 2487 * obsoleted we do not go looking around for all parent 2488 * referencing XFRM dsts so that we can invalidate them. It 2489 * is just too much work. Instead we make the checks here on 2490 * every use. For example: 2491 * 2492 * XFRM dst A --> IPv4 dst X 2493 * 2494 * X is the "xdst->route" of A (X is also the "dst->path" of A 2495 * in this example). If X is marked obsolete, "A" will not 2496 * notice. That's what we are validating here via the 2497 * stale_bundle() check. 2498 * 2499 * When a policy's bundle is pruned, we dst_free() the XFRM 2500 * dst which causes it's ->obsolete field to be set to 2501 * DST_OBSOLETE_DEAD. If an XFRM dst has been pruned like 2502 * this, we want to force a new route lookup. 2503 */ 2504 if (dst->obsolete < 0 && !stale_bundle(dst)) 2505 return dst; 2506 2507 return NULL; 2508 } 2509 2510 static int stale_bundle(struct dst_entry *dst) 2511 { 2512 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 2513 } 2514 2515 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 2516 { 2517 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { 2518 dst->dev = dev_net(dev)->loopback_dev; 2519 dev_hold(dst->dev); 2520 dev_put(dev); 2521 } 2522 } 2523 EXPORT_SYMBOL(xfrm_dst_ifdown); 2524 2525 static void xfrm_link_failure(struct sk_buff *skb) 2526 { 2527 /* Impossible. Such dst must be popped before reaches point of failure. */ 2528 } 2529 2530 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 2531 { 2532 if (dst) { 2533 if (dst->obsolete) { 2534 dst_release(dst); 2535 dst = NULL; 2536 } 2537 } 2538 return dst; 2539 } 2540 2541 static void __xfrm_garbage_collect(struct net *net) 2542 { 2543 struct dst_entry *head, *next; 2544 2545 spin_lock_bh(&xfrm_policy_sk_bundle_lock); 2546 head = xfrm_policy_sk_bundles; 2547 xfrm_policy_sk_bundles = NULL; 2548 spin_unlock_bh(&xfrm_policy_sk_bundle_lock); 2549 2550 while (head) { 2551 next = head->next; 2552 dst_free(head); 2553 head = next; 2554 } 2555 } 2556 2557 void xfrm_garbage_collect(struct net *net) 2558 { 2559 flow_cache_flush(); 2560 __xfrm_garbage_collect(net); 2561 } 2562 EXPORT_SYMBOL(xfrm_garbage_collect); 2563 2564 static void xfrm_garbage_collect_deferred(struct net *net) 2565 { 2566 flow_cache_flush_deferred(); 2567 __xfrm_garbage_collect(net); 2568 } 2569 2570 static void xfrm_init_pmtu(struct dst_entry *dst) 2571 { 2572 do { 2573 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2574 u32 pmtu, route_mtu_cached; 2575 2576 pmtu = dst_mtu(dst->child); 2577 xdst->child_mtu_cached = pmtu; 2578 2579 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 2580 2581 route_mtu_cached = dst_mtu(xdst->route); 2582 xdst->route_mtu_cached = route_mtu_cached; 2583 2584 if (pmtu > route_mtu_cached) 2585 pmtu = route_mtu_cached; 2586 2587 dst_metric_set(dst, RTAX_MTU, pmtu); 2588 } while ((dst = dst->next)); 2589 } 2590 2591 /* Check that the bundle accepts the flow and its components are 2592 * still valid. 2593 */ 2594 2595 static int xfrm_bundle_ok(struct xfrm_dst *first) 2596 { 2597 struct dst_entry *dst = &first->u.dst; 2598 struct xfrm_dst *last; 2599 u32 mtu; 2600 2601 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) || 2602 (dst->dev && !netif_running(dst->dev))) 2603 return 0; 2604 2605 if (dst->flags & DST_XFRM_QUEUE) 2606 return 1; 2607 2608 last = NULL; 2609 2610 do { 2611 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2612 2613 if (dst->xfrm->km.state != XFRM_STATE_VALID) 2614 return 0; 2615 if (xdst->xfrm_genid != dst->xfrm->genid) 2616 return 0; 2617 if (xdst->num_pols > 0 && 2618 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 2619 return 0; 2620 2621 mtu = dst_mtu(dst->child); 2622 if (xdst->child_mtu_cached != mtu) { 2623 last = xdst; 2624 xdst->child_mtu_cached = mtu; 2625 } 2626 2627 if (!dst_check(xdst->route, xdst->route_cookie)) 2628 return 0; 2629 mtu = dst_mtu(xdst->route); 2630 if (xdst->route_mtu_cached != mtu) { 2631 last = xdst; 2632 xdst->route_mtu_cached = mtu; 2633 } 2634 2635 dst = dst->child; 2636 } while (dst->xfrm); 2637 2638 if (likely(!last)) 2639 return 1; 2640 2641 mtu = last->child_mtu_cached; 2642 for (;;) { 2643 dst = &last->u.dst; 2644 2645 mtu = xfrm_state_mtu(dst->xfrm, mtu); 2646 if (mtu > last->route_mtu_cached) 2647 mtu = last->route_mtu_cached; 2648 dst_metric_set(dst, RTAX_MTU, mtu); 2649 2650 if (last == first) 2651 break; 2652 2653 last = (struct xfrm_dst *)last->u.dst.next; 2654 last->child_mtu_cached = mtu; 2655 } 2656 2657 return 1; 2658 } 2659 2660 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 2661 { 2662 return dst_metric_advmss(dst->path); 2663 } 2664 2665 static unsigned int xfrm_mtu(const struct dst_entry *dst) 2666 { 2667 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 2668 2669 return mtu ? : dst_mtu(dst->path); 2670 } 2671 2672 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 2673 struct sk_buff *skb, 2674 const void *daddr) 2675 { 2676 return dst->path->ops->neigh_lookup(dst, skb, daddr); 2677 } 2678 2679 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo) 2680 { 2681 struct net *net; 2682 int err = 0; 2683 if (unlikely(afinfo == NULL)) 2684 return -EINVAL; 2685 if (unlikely(afinfo->family >= NPROTO)) 2686 return -EAFNOSUPPORT; 2687 spin_lock(&xfrm_policy_afinfo_lock); 2688 if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL)) 2689 err = -ENOBUFS; 2690 else { 2691 struct dst_ops *dst_ops = afinfo->dst_ops; 2692 if (likely(dst_ops->kmem_cachep == NULL)) 2693 dst_ops->kmem_cachep = xfrm_dst_cache; 2694 if (likely(dst_ops->check == NULL)) 2695 dst_ops->check = xfrm_dst_check; 2696 if (likely(dst_ops->default_advmss == NULL)) 2697 dst_ops->default_advmss = xfrm_default_advmss; 2698 if (likely(dst_ops->mtu == NULL)) 2699 dst_ops->mtu = xfrm_mtu; 2700 if (likely(dst_ops->negative_advice == NULL)) 2701 dst_ops->negative_advice = xfrm_negative_advice; 2702 if (likely(dst_ops->link_failure == NULL)) 2703 dst_ops->link_failure = xfrm_link_failure; 2704 if (likely(dst_ops->neigh_lookup == NULL)) 2705 dst_ops->neigh_lookup = xfrm_neigh_lookup; 2706 if (likely(afinfo->garbage_collect == NULL)) 2707 afinfo->garbage_collect = xfrm_garbage_collect_deferred; 2708 rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo); 2709 } 2710 spin_unlock(&xfrm_policy_afinfo_lock); 2711 2712 rtnl_lock(); 2713 for_each_net(net) { 2714 struct dst_ops *xfrm_dst_ops; 2715 2716 switch (afinfo->family) { 2717 case AF_INET: 2718 xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops; 2719 break; 2720 #if IS_ENABLED(CONFIG_IPV6) 2721 case AF_INET6: 2722 xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops; 2723 break; 2724 #endif 2725 default: 2726 BUG(); 2727 } 2728 *xfrm_dst_ops = *afinfo->dst_ops; 2729 } 2730 rtnl_unlock(); 2731 2732 return err; 2733 } 2734 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 2735 2736 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo) 2737 { 2738 int err = 0; 2739 if (unlikely(afinfo == NULL)) 2740 return -EINVAL; 2741 if (unlikely(afinfo->family >= NPROTO)) 2742 return -EAFNOSUPPORT; 2743 spin_lock(&xfrm_policy_afinfo_lock); 2744 if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) { 2745 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo)) 2746 err = -EINVAL; 2747 else 2748 RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family], 2749 NULL); 2750 } 2751 spin_unlock(&xfrm_policy_afinfo_lock); 2752 if (!err) { 2753 struct dst_ops *dst_ops = afinfo->dst_ops; 2754 2755 synchronize_rcu(); 2756 2757 dst_ops->kmem_cachep = NULL; 2758 dst_ops->check = NULL; 2759 dst_ops->negative_advice = NULL; 2760 dst_ops->link_failure = NULL; 2761 afinfo->garbage_collect = NULL; 2762 } 2763 return err; 2764 } 2765 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 2766 2767 static void __net_init xfrm_dst_ops_init(struct net *net) 2768 { 2769 struct xfrm_policy_afinfo *afinfo; 2770 2771 rcu_read_lock(); 2772 afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]); 2773 if (afinfo) 2774 net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops; 2775 #if IS_ENABLED(CONFIG_IPV6) 2776 afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]); 2777 if (afinfo) 2778 net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops; 2779 #endif 2780 rcu_read_unlock(); 2781 } 2782 2783 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr) 2784 { 2785 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 2786 2787 switch (event) { 2788 case NETDEV_DOWN: 2789 xfrm_garbage_collect(dev_net(dev)); 2790 } 2791 return NOTIFY_DONE; 2792 } 2793 2794 static struct notifier_block xfrm_dev_notifier = { 2795 .notifier_call = xfrm_dev_event, 2796 }; 2797 2798 #ifdef CONFIG_XFRM_STATISTICS 2799 static int __net_init xfrm_statistics_init(struct net *net) 2800 { 2801 int rv; 2802 2803 if (snmp_mib_init((void __percpu **)net->mib.xfrm_statistics, 2804 sizeof(struct linux_xfrm_mib), 2805 __alignof__(struct linux_xfrm_mib)) < 0) 2806 return -ENOMEM; 2807 rv = xfrm_proc_init(net); 2808 if (rv < 0) 2809 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics); 2810 return rv; 2811 } 2812 2813 static void xfrm_statistics_fini(struct net *net) 2814 { 2815 xfrm_proc_fini(net); 2816 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics); 2817 } 2818 #else 2819 static int __net_init xfrm_statistics_init(struct net *net) 2820 { 2821 return 0; 2822 } 2823 2824 static void xfrm_statistics_fini(struct net *net) 2825 { 2826 } 2827 #endif 2828 2829 static int __net_init xfrm_policy_init(struct net *net) 2830 { 2831 unsigned int hmask, sz; 2832 int dir; 2833 2834 if (net_eq(net, &init_net)) 2835 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 2836 sizeof(struct xfrm_dst), 2837 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 2838 NULL); 2839 2840 hmask = 8 - 1; 2841 sz = (hmask+1) * sizeof(struct hlist_head); 2842 2843 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 2844 if (!net->xfrm.policy_byidx) 2845 goto out_byidx; 2846 net->xfrm.policy_idx_hmask = hmask; 2847 2848 for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) { 2849 struct xfrm_policy_hash *htab; 2850 2851 net->xfrm.policy_count[dir] = 0; 2852 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 2853 2854 htab = &net->xfrm.policy_bydst[dir]; 2855 htab->table = xfrm_hash_alloc(sz); 2856 if (!htab->table) 2857 goto out_bydst; 2858 htab->hmask = hmask; 2859 } 2860 2861 INIT_LIST_HEAD(&net->xfrm.policy_all); 2862 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 2863 if (net_eq(net, &init_net)) 2864 register_netdevice_notifier(&xfrm_dev_notifier); 2865 return 0; 2866 2867 out_bydst: 2868 for (dir--; dir >= 0; dir--) { 2869 struct xfrm_policy_hash *htab; 2870 2871 htab = &net->xfrm.policy_bydst[dir]; 2872 xfrm_hash_free(htab->table, sz); 2873 } 2874 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2875 out_byidx: 2876 return -ENOMEM; 2877 } 2878 2879 static void xfrm_policy_fini(struct net *net) 2880 { 2881 struct xfrm_audit audit_info; 2882 unsigned int sz; 2883 int dir; 2884 2885 flush_work(&net->xfrm.policy_hash_work); 2886 #ifdef CONFIG_XFRM_SUB_POLICY 2887 audit_info.loginuid = INVALID_UID; 2888 audit_info.sessionid = -1; 2889 audit_info.secid = 0; 2890 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info); 2891 #endif 2892 audit_info.loginuid = INVALID_UID; 2893 audit_info.sessionid = -1; 2894 audit_info.secid = 0; 2895 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info); 2896 2897 WARN_ON(!list_empty(&net->xfrm.policy_all)); 2898 2899 for (dir = 0; dir < XFRM_POLICY_MAX * 2; 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 rv = xfrm_statistics_init(net); 2920 if (rv < 0) 2921 goto out_statistics; 2922 rv = xfrm_state_init(net); 2923 if (rv < 0) 2924 goto out_state; 2925 rv = xfrm_policy_init(net); 2926 if (rv < 0) 2927 goto out_policy; 2928 xfrm_dst_ops_init(net); 2929 rv = xfrm_sysctl_init(net); 2930 if (rv < 0) 2931 goto out_sysctl; 2932 return 0; 2933 2934 out_sysctl: 2935 xfrm_policy_fini(net); 2936 out_policy: 2937 xfrm_state_fini(net); 2938 out_state: 2939 xfrm_statistics_fini(net); 2940 out_statistics: 2941 return rv; 2942 } 2943 2944 static void __net_exit xfrm_net_exit(struct net *net) 2945 { 2946 xfrm_sysctl_fini(net); 2947 xfrm_policy_fini(net); 2948 xfrm_state_fini(net); 2949 xfrm_statistics_fini(net); 2950 } 2951 2952 static struct pernet_operations __net_initdata xfrm_net_ops = { 2953 .init = xfrm_net_init, 2954 .exit = xfrm_net_exit, 2955 }; 2956 2957 void __init xfrm_init(void) 2958 { 2959 register_pernet_subsys(&xfrm_net_ops); 2960 xfrm_input_init(); 2961 } 2962 2963 #ifdef CONFIG_AUDITSYSCALL 2964 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 2965 struct audit_buffer *audit_buf) 2966 { 2967 struct xfrm_sec_ctx *ctx = xp->security; 2968 struct xfrm_selector *sel = &xp->selector; 2969 2970 if (ctx) 2971 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 2972 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 2973 2974 switch(sel->family) { 2975 case AF_INET: 2976 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 2977 if (sel->prefixlen_s != 32) 2978 audit_log_format(audit_buf, " src_prefixlen=%d", 2979 sel->prefixlen_s); 2980 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 2981 if (sel->prefixlen_d != 32) 2982 audit_log_format(audit_buf, " dst_prefixlen=%d", 2983 sel->prefixlen_d); 2984 break; 2985 case AF_INET6: 2986 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 2987 if (sel->prefixlen_s != 128) 2988 audit_log_format(audit_buf, " src_prefixlen=%d", 2989 sel->prefixlen_s); 2990 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 2991 if (sel->prefixlen_d != 128) 2992 audit_log_format(audit_buf, " dst_prefixlen=%d", 2993 sel->prefixlen_d); 2994 break; 2995 } 2996 } 2997 2998 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, 2999 kuid_t auid, u32 sessionid, u32 secid) 3000 { 3001 struct audit_buffer *audit_buf; 3002 3003 audit_buf = xfrm_audit_start("SPD-add"); 3004 if (audit_buf == NULL) 3005 return; 3006 xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf); 3007 audit_log_format(audit_buf, " res=%u", result); 3008 xfrm_audit_common_policyinfo(xp, audit_buf); 3009 audit_log_end(audit_buf); 3010 } 3011 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 3012 3013 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 3014 kuid_t auid, u32 sessionid, u32 secid) 3015 { 3016 struct audit_buffer *audit_buf; 3017 3018 audit_buf = xfrm_audit_start("SPD-delete"); 3019 if (audit_buf == NULL) 3020 return; 3021 xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf); 3022 audit_log_format(audit_buf, " res=%u", result); 3023 xfrm_audit_common_policyinfo(xp, audit_buf); 3024 audit_log_end(audit_buf); 3025 } 3026 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 3027 #endif 3028 3029 #ifdef CONFIG_XFRM_MIGRATE 3030 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 3031 const struct xfrm_selector *sel_tgt) 3032 { 3033 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 3034 if (sel_tgt->family == sel_cmp->family && 3035 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 3036 sel_cmp->family) && 3037 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 3038 sel_cmp->family) && 3039 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 3040 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 3041 return true; 3042 } 3043 } else { 3044 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 3045 return true; 3046 } 3047 } 3048 return false; 3049 } 3050 3051 static struct xfrm_policy * xfrm_migrate_policy_find(const struct xfrm_selector *sel, 3052 u8 dir, u8 type) 3053 { 3054 struct xfrm_policy *pol, *ret = NULL; 3055 struct hlist_head *chain; 3056 u32 priority = ~0U; 3057 3058 read_lock_bh(&xfrm_policy_lock); 3059 chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir); 3060 hlist_for_each_entry(pol, chain, bydst) { 3061 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3062 pol->type == type) { 3063 ret = pol; 3064 priority = ret->priority; 3065 break; 3066 } 3067 } 3068 chain = &init_net.xfrm.policy_inexact[dir]; 3069 hlist_for_each_entry(pol, chain, bydst) { 3070 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3071 pol->type == type && 3072 pol->priority < priority) { 3073 ret = pol; 3074 break; 3075 } 3076 } 3077 3078 if (ret) 3079 xfrm_pol_hold(ret); 3080 3081 read_unlock_bh(&xfrm_policy_lock); 3082 3083 return ret; 3084 } 3085 3086 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 3087 { 3088 int match = 0; 3089 3090 if (t->mode == m->mode && t->id.proto == m->proto && 3091 (m->reqid == 0 || t->reqid == m->reqid)) { 3092 switch (t->mode) { 3093 case XFRM_MODE_TUNNEL: 3094 case XFRM_MODE_BEET: 3095 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 3096 m->old_family) && 3097 xfrm_addr_equal(&t->saddr, &m->old_saddr, 3098 m->old_family)) { 3099 match = 1; 3100 } 3101 break; 3102 case XFRM_MODE_TRANSPORT: 3103 /* in case of transport mode, template does not store 3104 any IP addresses, hence we just compare mode and 3105 protocol */ 3106 match = 1; 3107 break; 3108 default: 3109 break; 3110 } 3111 } 3112 return match; 3113 } 3114 3115 /* update endpoint address(es) of template(s) */ 3116 static int xfrm_policy_migrate(struct xfrm_policy *pol, 3117 struct xfrm_migrate *m, int num_migrate) 3118 { 3119 struct xfrm_migrate *mp; 3120 int i, j, n = 0; 3121 3122 write_lock_bh(&pol->lock); 3123 if (unlikely(pol->walk.dead)) { 3124 /* target policy has been deleted */ 3125 write_unlock_bh(&pol->lock); 3126 return -ENOENT; 3127 } 3128 3129 for (i = 0; i < pol->xfrm_nr; i++) { 3130 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 3131 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 3132 continue; 3133 n++; 3134 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 3135 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 3136 continue; 3137 /* update endpoints */ 3138 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 3139 sizeof(pol->xfrm_vec[i].id.daddr)); 3140 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 3141 sizeof(pol->xfrm_vec[i].saddr)); 3142 pol->xfrm_vec[i].encap_family = mp->new_family; 3143 /* flush bundles */ 3144 atomic_inc(&pol->genid); 3145 } 3146 } 3147 3148 write_unlock_bh(&pol->lock); 3149 3150 if (!n) 3151 return -ENODATA; 3152 3153 return 0; 3154 } 3155 3156 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 3157 { 3158 int i, j; 3159 3160 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 3161 return -EINVAL; 3162 3163 for (i = 0; i < num_migrate; i++) { 3164 if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr, 3165 m[i].old_family) && 3166 xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr, 3167 m[i].old_family)) 3168 return -EINVAL; 3169 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 3170 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 3171 return -EINVAL; 3172 3173 /* check if there is any duplicated entry */ 3174 for (j = i + 1; j < num_migrate; j++) { 3175 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 3176 sizeof(m[i].old_daddr)) && 3177 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 3178 sizeof(m[i].old_saddr)) && 3179 m[i].proto == m[j].proto && 3180 m[i].mode == m[j].mode && 3181 m[i].reqid == m[j].reqid && 3182 m[i].old_family == m[j].old_family) 3183 return -EINVAL; 3184 } 3185 } 3186 3187 return 0; 3188 } 3189 3190 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 3191 struct xfrm_migrate *m, int num_migrate, 3192 struct xfrm_kmaddress *k) 3193 { 3194 int i, err, nx_cur = 0, nx_new = 0; 3195 struct xfrm_policy *pol = NULL; 3196 struct xfrm_state *x, *xc; 3197 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 3198 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 3199 struct xfrm_migrate *mp; 3200 3201 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 3202 goto out; 3203 3204 /* Stage 1 - find policy */ 3205 if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) { 3206 err = -ENOENT; 3207 goto out; 3208 } 3209 3210 /* Stage 2 - find and update state(s) */ 3211 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 3212 if ((x = xfrm_migrate_state_find(mp))) { 3213 x_cur[nx_cur] = x; 3214 nx_cur++; 3215 if ((xc = xfrm_state_migrate(x, mp))) { 3216 x_new[nx_new] = xc; 3217 nx_new++; 3218 } else { 3219 err = -ENODATA; 3220 goto restore_state; 3221 } 3222 } 3223 } 3224 3225 /* Stage 3 - update policy */ 3226 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 3227 goto restore_state; 3228 3229 /* Stage 4 - delete old state(s) */ 3230 if (nx_cur) { 3231 xfrm_states_put(x_cur, nx_cur); 3232 xfrm_states_delete(x_cur, nx_cur); 3233 } 3234 3235 /* Stage 5 - announce */ 3236 km_migrate(sel, dir, type, m, num_migrate, k); 3237 3238 xfrm_pol_put(pol); 3239 3240 return 0; 3241 out: 3242 return err; 3243 3244 restore_state: 3245 if (pol) 3246 xfrm_pol_put(pol); 3247 if (nx_cur) 3248 xfrm_states_put(x_cur, nx_cur); 3249 if (nx_new) 3250 xfrm_states_delete(x_new, nx_new); 3251 3252 return err; 3253 } 3254 EXPORT_SYMBOL(xfrm_migrate); 3255 #endif 3256