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