1 /* 2 * xfrm_policy.c 3 * 4 * Changes: 5 * Mitsuru KANDA @USAGI 6 * Kazunori MIYAZAWA @USAGI 7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 8 * IPv6 support 9 * Kazunori MIYAZAWA @USAGI 10 * YOSHIFUJI Hideaki 11 * Split up af-specific portion 12 * Derek Atkins <derek@ihtfp.com> Add the post_input processor 13 * 14 */ 15 16 #include <linux/err.h> 17 #include <linux/slab.h> 18 #include <linux/kmod.h> 19 #include <linux/list.h> 20 #include <linux/spinlock.h> 21 #include <linux/workqueue.h> 22 #include <linux/notifier.h> 23 #include <linux/netdevice.h> 24 #include <linux/netfilter.h> 25 #include <linux/module.h> 26 #include <linux/cache.h> 27 #include <linux/cpu.h> 28 #include <linux/audit.h> 29 #include <net/dst.h> 30 #include <net/flow.h> 31 #include <net/xfrm.h> 32 #include <net/ip.h> 33 #ifdef CONFIG_XFRM_STATISTICS 34 #include <net/snmp.h> 35 #endif 36 37 #include "xfrm_hash.h" 38 39 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10)) 40 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ)) 41 #define XFRM_MAX_QUEUE_LEN 100 42 43 struct xfrm_flo { 44 struct dst_entry *dst_orig; 45 u8 flags; 46 }; 47 48 static DEFINE_PER_CPU(struct xfrm_dst *, xfrm_last_dst); 49 static struct work_struct *xfrm_pcpu_work __read_mostly; 50 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 51 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 52 __read_mostly; 53 54 static struct kmem_cache *xfrm_dst_cache __read_mostly; 55 static __read_mostly seqcount_t xfrm_policy_hash_generation; 56 57 static void xfrm_init_pmtu(struct dst_entry *dst); 58 static int stale_bundle(struct dst_entry *dst); 59 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 60 static void xfrm_policy_queue_process(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 = xfrm_selector_match(&pol->selector, fl, family); 1172 int err = 0; 1173 1174 if (match) { 1175 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) { 1176 pol = NULL; 1177 goto out; 1178 } 1179 err = security_xfrm_policy_lookup(pol->security, 1180 fl->flowi_secid, 1181 dir); 1182 if (!err) { 1183 if (!xfrm_pol_hold_rcu(pol)) 1184 goto again; 1185 } else if (err == -ESRCH) { 1186 pol = NULL; 1187 } else { 1188 pol = ERR_PTR(err); 1189 } 1190 } else 1191 pol = NULL; 1192 } 1193 out: 1194 rcu_read_unlock(); 1195 return pol; 1196 } 1197 1198 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 1199 { 1200 struct net *net = xp_net(pol); 1201 1202 list_add(&pol->walk.all, &net->xfrm.policy_all); 1203 net->xfrm.policy_count[dir]++; 1204 xfrm_pol_hold(pol); 1205 } 1206 1207 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 1208 int dir) 1209 { 1210 struct net *net = xp_net(pol); 1211 1212 if (list_empty(&pol->walk.all)) 1213 return NULL; 1214 1215 /* Socket policies are not hashed. */ 1216 if (!hlist_unhashed(&pol->bydst)) { 1217 hlist_del_rcu(&pol->bydst); 1218 hlist_del(&pol->byidx); 1219 } 1220 1221 list_del_init(&pol->walk.all); 1222 net->xfrm.policy_count[dir]--; 1223 1224 return pol; 1225 } 1226 1227 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 1228 { 1229 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 1230 } 1231 1232 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 1233 { 1234 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 1235 } 1236 1237 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 1238 { 1239 struct net *net = xp_net(pol); 1240 1241 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1242 pol = __xfrm_policy_unlink(pol, dir); 1243 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1244 if (pol) { 1245 xfrm_policy_kill(pol); 1246 return 0; 1247 } 1248 return -ENOENT; 1249 } 1250 EXPORT_SYMBOL(xfrm_policy_delete); 1251 1252 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 1253 { 1254 struct net *net = xp_net(pol); 1255 struct xfrm_policy *old_pol; 1256 1257 #ifdef CONFIG_XFRM_SUB_POLICY 1258 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 1259 return -EINVAL; 1260 #endif 1261 1262 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1263 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 1264 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 1265 if (pol) { 1266 pol->curlft.add_time = get_seconds(); 1267 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 1268 xfrm_sk_policy_link(pol, dir); 1269 } 1270 rcu_assign_pointer(sk->sk_policy[dir], pol); 1271 if (old_pol) { 1272 if (pol) 1273 xfrm_policy_requeue(old_pol, pol); 1274 1275 /* Unlinking succeeds always. This is the only function 1276 * allowed to delete or replace socket policy. 1277 */ 1278 xfrm_sk_policy_unlink(old_pol, dir); 1279 } 1280 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1281 1282 if (old_pol) { 1283 xfrm_policy_kill(old_pol); 1284 } 1285 return 0; 1286 } 1287 1288 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 1289 { 1290 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 1291 struct net *net = xp_net(old); 1292 1293 if (newp) { 1294 newp->selector = old->selector; 1295 if (security_xfrm_policy_clone(old->security, 1296 &newp->security)) { 1297 kfree(newp); 1298 return NULL; /* ENOMEM */ 1299 } 1300 newp->lft = old->lft; 1301 newp->curlft = old->curlft; 1302 newp->mark = old->mark; 1303 newp->action = old->action; 1304 newp->flags = old->flags; 1305 newp->xfrm_nr = old->xfrm_nr; 1306 newp->index = old->index; 1307 newp->type = old->type; 1308 memcpy(newp->xfrm_vec, old->xfrm_vec, 1309 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 1310 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1311 xfrm_sk_policy_link(newp, dir); 1312 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1313 xfrm_pol_put(newp); 1314 } 1315 return newp; 1316 } 1317 1318 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 1319 { 1320 const struct xfrm_policy *p; 1321 struct xfrm_policy *np; 1322 int i, ret = 0; 1323 1324 rcu_read_lock(); 1325 for (i = 0; i < 2; i++) { 1326 p = rcu_dereference(osk->sk_policy[i]); 1327 if (p) { 1328 np = clone_policy(p, i); 1329 if (unlikely(!np)) { 1330 ret = -ENOMEM; 1331 break; 1332 } 1333 rcu_assign_pointer(sk->sk_policy[i], np); 1334 } 1335 } 1336 rcu_read_unlock(); 1337 return ret; 1338 } 1339 1340 static int 1341 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 1342 xfrm_address_t *remote, unsigned short family, u32 mark) 1343 { 1344 int err; 1345 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1346 1347 if (unlikely(afinfo == NULL)) 1348 return -EINVAL; 1349 err = afinfo->get_saddr(net, oif, local, remote, mark); 1350 rcu_read_unlock(); 1351 return err; 1352 } 1353 1354 /* Resolve list of templates for the flow, given policy. */ 1355 1356 static int 1357 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 1358 struct xfrm_state **xfrm, unsigned short family) 1359 { 1360 struct net *net = xp_net(policy); 1361 int nx; 1362 int i, error; 1363 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 1364 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 1365 xfrm_address_t tmp; 1366 1367 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 1368 struct xfrm_state *x; 1369 xfrm_address_t *remote = daddr; 1370 xfrm_address_t *local = saddr; 1371 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 1372 1373 if (tmpl->mode == XFRM_MODE_TUNNEL || 1374 tmpl->mode == XFRM_MODE_BEET) { 1375 remote = &tmpl->id.daddr; 1376 local = &tmpl->saddr; 1377 if (xfrm_addr_any(local, tmpl->encap_family)) { 1378 error = xfrm_get_saddr(net, fl->flowi_oif, 1379 &tmp, remote, 1380 tmpl->encap_family, 0); 1381 if (error) 1382 goto fail; 1383 local = &tmp; 1384 } 1385 } 1386 1387 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); 1388 1389 if (x && x->km.state == XFRM_STATE_VALID) { 1390 xfrm[nx++] = x; 1391 daddr = remote; 1392 saddr = local; 1393 continue; 1394 } 1395 if (x) { 1396 error = (x->km.state == XFRM_STATE_ERROR ? 1397 -EINVAL : -EAGAIN); 1398 xfrm_state_put(x); 1399 } else if (error == -ESRCH) { 1400 error = -EAGAIN; 1401 } 1402 1403 if (!tmpl->optional) 1404 goto fail; 1405 } 1406 return nx; 1407 1408 fail: 1409 for (nx--; nx >= 0; nx--) 1410 xfrm_state_put(xfrm[nx]); 1411 return error; 1412 } 1413 1414 static int 1415 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 1416 struct xfrm_state **xfrm, unsigned short family) 1417 { 1418 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 1419 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 1420 int cnx = 0; 1421 int error; 1422 int ret; 1423 int i; 1424 1425 for (i = 0; i < npols; i++) { 1426 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 1427 error = -ENOBUFS; 1428 goto fail; 1429 } 1430 1431 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 1432 if (ret < 0) { 1433 error = ret; 1434 goto fail; 1435 } else 1436 cnx += ret; 1437 } 1438 1439 /* found states are sorted for outbound processing */ 1440 if (npols > 1) 1441 xfrm_state_sort(xfrm, tpp, cnx, family); 1442 1443 return cnx; 1444 1445 fail: 1446 for (cnx--; cnx >= 0; cnx--) 1447 xfrm_state_put(tpp[cnx]); 1448 return error; 1449 1450 } 1451 1452 static int xfrm_get_tos(const struct flowi *fl, int family) 1453 { 1454 const struct xfrm_policy_afinfo *afinfo; 1455 int tos = 0; 1456 1457 afinfo = xfrm_policy_get_afinfo(family); 1458 tos = afinfo ? afinfo->get_tos(fl) : 0; 1459 1460 rcu_read_unlock(); 1461 1462 return tos; 1463 } 1464 1465 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 1466 { 1467 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1468 struct dst_ops *dst_ops; 1469 struct xfrm_dst *xdst; 1470 1471 if (!afinfo) 1472 return ERR_PTR(-EINVAL); 1473 1474 switch (family) { 1475 case AF_INET: 1476 dst_ops = &net->xfrm.xfrm4_dst_ops; 1477 break; 1478 #if IS_ENABLED(CONFIG_IPV6) 1479 case AF_INET6: 1480 dst_ops = &net->xfrm.xfrm6_dst_ops; 1481 break; 1482 #endif 1483 default: 1484 BUG(); 1485 } 1486 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 1487 1488 if (likely(xdst)) { 1489 struct dst_entry *dst = &xdst->u.dst; 1490 1491 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 1492 } else 1493 xdst = ERR_PTR(-ENOBUFS); 1494 1495 rcu_read_unlock(); 1496 1497 return xdst; 1498 } 1499 1500 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 1501 int nfheader_len) 1502 { 1503 const struct xfrm_policy_afinfo *afinfo = 1504 xfrm_policy_get_afinfo(dst->ops->family); 1505 int err; 1506 1507 if (!afinfo) 1508 return -EINVAL; 1509 1510 err = afinfo->init_path(path, dst, nfheader_len); 1511 1512 rcu_read_unlock(); 1513 1514 return err; 1515 } 1516 1517 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 1518 const struct flowi *fl) 1519 { 1520 const struct xfrm_policy_afinfo *afinfo = 1521 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 1522 int err; 1523 1524 if (!afinfo) 1525 return -EINVAL; 1526 1527 err = afinfo->fill_dst(xdst, dev, fl); 1528 1529 rcu_read_unlock(); 1530 1531 return err; 1532 } 1533 1534 1535 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 1536 * all the metrics... Shortly, bundle a bundle. 1537 */ 1538 1539 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 1540 struct xfrm_state **xfrm, int nx, 1541 const struct flowi *fl, 1542 struct dst_entry *dst) 1543 { 1544 struct net *net = xp_net(policy); 1545 unsigned long now = jiffies; 1546 struct net_device *dev; 1547 struct xfrm_mode *inner_mode; 1548 struct dst_entry *dst_prev = NULL; 1549 struct dst_entry *dst0 = NULL; 1550 int i = 0; 1551 int err; 1552 int header_len = 0; 1553 int nfheader_len = 0; 1554 int trailer_len = 0; 1555 int tos; 1556 int family = policy->selector.family; 1557 xfrm_address_t saddr, daddr; 1558 1559 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 1560 1561 tos = xfrm_get_tos(fl, family); 1562 1563 dst_hold(dst); 1564 1565 for (; i < nx; i++) { 1566 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 1567 struct dst_entry *dst1 = &xdst->u.dst; 1568 1569 err = PTR_ERR(xdst); 1570 if (IS_ERR(xdst)) { 1571 dst_release(dst); 1572 goto put_states; 1573 } 1574 1575 if (!dst_prev) 1576 dst0 = dst1; 1577 else 1578 /* Ref count is taken during xfrm_alloc_dst() 1579 * No need to do dst_clone() on dst1 1580 */ 1581 dst_prev->child = dst1; 1582 1583 if (xfrm[i]->sel.family == AF_UNSPEC) { 1584 inner_mode = xfrm_ip2inner_mode(xfrm[i], 1585 xfrm_af2proto(family)); 1586 if (!inner_mode) { 1587 err = -EAFNOSUPPORT; 1588 dst_release(dst); 1589 goto put_states; 1590 } 1591 } else 1592 inner_mode = xfrm[i]->inner_mode; 1593 1594 xdst->route = dst; 1595 dst_copy_metrics(dst1, dst); 1596 1597 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 1598 family = xfrm[i]->props.family; 1599 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 1600 &saddr, &daddr, family, 1601 xfrm[i]->props.output_mark); 1602 err = PTR_ERR(dst); 1603 if (IS_ERR(dst)) 1604 goto put_states; 1605 } else 1606 dst_hold(dst); 1607 1608 dst1->xfrm = xfrm[i]; 1609 xdst->xfrm_genid = xfrm[i]->genid; 1610 1611 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1612 dst1->flags |= DST_HOST; 1613 dst1->lastuse = now; 1614 1615 dst1->input = dst_discard; 1616 dst1->output = inner_mode->afinfo->output; 1617 1618 dst1->next = dst_prev; 1619 dst_prev = dst1; 1620 1621 header_len += xfrm[i]->props.header_len; 1622 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 1623 nfheader_len += xfrm[i]->props.header_len; 1624 trailer_len += xfrm[i]->props.trailer_len; 1625 } 1626 1627 dst_prev->child = dst; 1628 dst0->path = dst; 1629 1630 err = -ENODEV; 1631 dev = dst->dev; 1632 if (!dev) 1633 goto free_dst; 1634 1635 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len); 1636 xfrm_init_pmtu(dst_prev); 1637 1638 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) { 1639 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev; 1640 1641 err = xfrm_fill_dst(xdst, dev, fl); 1642 if (err) 1643 goto free_dst; 1644 1645 dst_prev->header_len = header_len; 1646 dst_prev->trailer_len = trailer_len; 1647 header_len -= xdst->u.dst.xfrm->props.header_len; 1648 trailer_len -= xdst->u.dst.xfrm->props.trailer_len; 1649 } 1650 1651 out: 1652 return dst0; 1653 1654 put_states: 1655 for (; i < nx; i++) 1656 xfrm_state_put(xfrm[i]); 1657 free_dst: 1658 if (dst0) 1659 dst_release_immediate(dst0); 1660 dst0 = ERR_PTR(err); 1661 goto out; 1662 } 1663 1664 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 1665 struct xfrm_policy **pols, 1666 int *num_pols, int *num_xfrms) 1667 { 1668 int i; 1669 1670 if (*num_pols == 0 || !pols[0]) { 1671 *num_pols = 0; 1672 *num_xfrms = 0; 1673 return 0; 1674 } 1675 if (IS_ERR(pols[0])) 1676 return PTR_ERR(pols[0]); 1677 1678 *num_xfrms = pols[0]->xfrm_nr; 1679 1680 #ifdef CONFIG_XFRM_SUB_POLICY 1681 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 1682 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 1683 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 1684 XFRM_POLICY_TYPE_MAIN, 1685 fl, family, 1686 XFRM_POLICY_OUT); 1687 if (pols[1]) { 1688 if (IS_ERR(pols[1])) { 1689 xfrm_pols_put(pols, *num_pols); 1690 return PTR_ERR(pols[1]); 1691 } 1692 (*num_pols)++; 1693 (*num_xfrms) += pols[1]->xfrm_nr; 1694 } 1695 } 1696 #endif 1697 for (i = 0; i < *num_pols; i++) { 1698 if (pols[i]->action != XFRM_POLICY_ALLOW) { 1699 *num_xfrms = -1; 1700 break; 1701 } 1702 } 1703 1704 return 0; 1705 1706 } 1707 1708 static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old) 1709 { 1710 this_cpu_write(xfrm_last_dst, xdst); 1711 if (old) 1712 dst_release(&old->u.dst); 1713 } 1714 1715 static void __xfrm_pcpu_work_fn(void) 1716 { 1717 struct xfrm_dst *old; 1718 1719 old = this_cpu_read(xfrm_last_dst); 1720 if (old && !xfrm_bundle_ok(old)) 1721 xfrm_last_dst_update(NULL, old); 1722 } 1723 1724 static void xfrm_pcpu_work_fn(struct work_struct *work) 1725 { 1726 local_bh_disable(); 1727 rcu_read_lock(); 1728 __xfrm_pcpu_work_fn(); 1729 rcu_read_unlock(); 1730 local_bh_enable(); 1731 } 1732 1733 void xfrm_policy_cache_flush(void) 1734 { 1735 struct xfrm_dst *old; 1736 bool found = 0; 1737 int cpu; 1738 1739 local_bh_disable(); 1740 rcu_read_lock(); 1741 for_each_possible_cpu(cpu) { 1742 old = per_cpu(xfrm_last_dst, cpu); 1743 if (old && !xfrm_bundle_ok(old)) { 1744 if (smp_processor_id() == cpu) { 1745 __xfrm_pcpu_work_fn(); 1746 continue; 1747 } 1748 found = true; 1749 break; 1750 } 1751 } 1752 1753 rcu_read_unlock(); 1754 local_bh_enable(); 1755 1756 if (!found) 1757 return; 1758 1759 get_online_cpus(); 1760 1761 for_each_possible_cpu(cpu) { 1762 bool bundle_release; 1763 1764 rcu_read_lock(); 1765 old = per_cpu(xfrm_last_dst, cpu); 1766 bundle_release = old && !xfrm_bundle_ok(old); 1767 rcu_read_unlock(); 1768 1769 if (!bundle_release) 1770 continue; 1771 1772 if (cpu_online(cpu)) { 1773 schedule_work_on(cpu, &xfrm_pcpu_work[cpu]); 1774 continue; 1775 } 1776 1777 rcu_read_lock(); 1778 old = per_cpu(xfrm_last_dst, cpu); 1779 if (old && !xfrm_bundle_ok(old)) { 1780 per_cpu(xfrm_last_dst, cpu) = NULL; 1781 dst_release(&old->u.dst); 1782 } 1783 rcu_read_unlock(); 1784 } 1785 1786 put_online_cpus(); 1787 } 1788 1789 static bool xfrm_pol_dead(struct xfrm_dst *xdst) 1790 { 1791 unsigned int num_pols = xdst->num_pols; 1792 unsigned int pol_dead = 0, i; 1793 1794 for (i = 0; i < num_pols; i++) 1795 pol_dead |= xdst->pols[i]->walk.dead; 1796 1797 /* Mark DST_OBSOLETE_DEAD to fail the next xfrm_dst_check() */ 1798 if (pol_dead) 1799 xdst->u.dst.obsolete = DST_OBSOLETE_DEAD; 1800 1801 return pol_dead; 1802 } 1803 1804 static struct xfrm_dst * 1805 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 1806 const struct flowi *fl, u16 family, 1807 struct dst_entry *dst_orig) 1808 { 1809 struct net *net = xp_net(pols[0]); 1810 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 1811 struct xfrm_dst *xdst, *old; 1812 struct dst_entry *dst; 1813 int err; 1814 1815 xdst = this_cpu_read(xfrm_last_dst); 1816 if (xdst && 1817 xdst->u.dst.dev == dst_orig->dev && 1818 xdst->num_pols == num_pols && 1819 !xfrm_pol_dead(xdst) && 1820 memcmp(xdst->pols, pols, 1821 sizeof(struct xfrm_policy *) * num_pols) == 0 && 1822 xfrm_bundle_ok(xdst)) { 1823 dst_hold(&xdst->u.dst); 1824 return xdst; 1825 } 1826 1827 old = xdst; 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 dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig); 1837 if (IS_ERR(dst)) { 1838 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 1839 return ERR_CAST(dst); 1840 } 1841 1842 xdst = (struct xfrm_dst *)dst; 1843 xdst->num_xfrms = err; 1844 xdst->num_pols = num_pols; 1845 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 1846 xdst->policy_genid = atomic_read(&pols[0]->genid); 1847 1848 atomic_set(&xdst->u.dst.__refcnt, 2); 1849 xfrm_last_dst_update(xdst, old); 1850 1851 return xdst; 1852 } 1853 1854 static void xfrm_policy_queue_process(struct timer_list *t) 1855 { 1856 struct sk_buff *skb; 1857 struct sock *sk; 1858 struct dst_entry *dst; 1859 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 1860 struct net *net = xp_net(pol); 1861 struct xfrm_policy_queue *pq = &pol->polq; 1862 struct flowi fl; 1863 struct sk_buff_head list; 1864 1865 spin_lock(&pq->hold_queue.lock); 1866 skb = skb_peek(&pq->hold_queue); 1867 if (!skb) { 1868 spin_unlock(&pq->hold_queue.lock); 1869 goto out; 1870 } 1871 dst = skb_dst(skb); 1872 sk = skb->sk; 1873 xfrm_decode_session(skb, &fl, dst->ops->family); 1874 spin_unlock(&pq->hold_queue.lock); 1875 1876 dst_hold(dst->path); 1877 dst = xfrm_lookup(net, dst->path, &fl, sk, 0); 1878 if (IS_ERR(dst)) 1879 goto purge_queue; 1880 1881 if (dst->flags & DST_XFRM_QUEUE) { 1882 dst_release(dst); 1883 1884 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 1885 goto purge_queue; 1886 1887 pq->timeout = pq->timeout << 1; 1888 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 1889 xfrm_pol_hold(pol); 1890 goto out; 1891 } 1892 1893 dst_release(dst); 1894 1895 __skb_queue_head_init(&list); 1896 1897 spin_lock(&pq->hold_queue.lock); 1898 pq->timeout = 0; 1899 skb_queue_splice_init(&pq->hold_queue, &list); 1900 spin_unlock(&pq->hold_queue.lock); 1901 1902 while (!skb_queue_empty(&list)) { 1903 skb = __skb_dequeue(&list); 1904 1905 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 1906 dst_hold(skb_dst(skb)->path); 1907 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0); 1908 if (IS_ERR(dst)) { 1909 kfree_skb(skb); 1910 continue; 1911 } 1912 1913 nf_reset(skb); 1914 skb_dst_drop(skb); 1915 skb_dst_set(skb, dst); 1916 1917 dst_output(net, skb->sk, skb); 1918 } 1919 1920 out: 1921 xfrm_pol_put(pol); 1922 return; 1923 1924 purge_queue: 1925 pq->timeout = 0; 1926 skb_queue_purge(&pq->hold_queue); 1927 xfrm_pol_put(pol); 1928 } 1929 1930 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 1931 { 1932 unsigned long sched_next; 1933 struct dst_entry *dst = skb_dst(skb); 1934 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 1935 struct xfrm_policy *pol = xdst->pols[0]; 1936 struct xfrm_policy_queue *pq = &pol->polq; 1937 1938 if (unlikely(skb_fclone_busy(sk, skb))) { 1939 kfree_skb(skb); 1940 return 0; 1941 } 1942 1943 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 1944 kfree_skb(skb); 1945 return -EAGAIN; 1946 } 1947 1948 skb_dst_force(skb); 1949 1950 spin_lock_bh(&pq->hold_queue.lock); 1951 1952 if (!pq->timeout) 1953 pq->timeout = XFRM_QUEUE_TMO_MIN; 1954 1955 sched_next = jiffies + pq->timeout; 1956 1957 if (del_timer(&pq->hold_timer)) { 1958 if (time_before(pq->hold_timer.expires, sched_next)) 1959 sched_next = pq->hold_timer.expires; 1960 xfrm_pol_put(pol); 1961 } 1962 1963 __skb_queue_tail(&pq->hold_queue, skb); 1964 if (!mod_timer(&pq->hold_timer, sched_next)) 1965 xfrm_pol_hold(pol); 1966 1967 spin_unlock_bh(&pq->hold_queue.lock); 1968 1969 return 0; 1970 } 1971 1972 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 1973 struct xfrm_flo *xflo, 1974 const struct flowi *fl, 1975 int num_xfrms, 1976 u16 family) 1977 { 1978 int err; 1979 struct net_device *dev; 1980 struct dst_entry *dst; 1981 struct dst_entry *dst1; 1982 struct xfrm_dst *xdst; 1983 1984 xdst = xfrm_alloc_dst(net, family); 1985 if (IS_ERR(xdst)) 1986 return xdst; 1987 1988 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 1989 net->xfrm.sysctl_larval_drop || 1990 num_xfrms <= 0) 1991 return xdst; 1992 1993 dst = xflo->dst_orig; 1994 dst1 = &xdst->u.dst; 1995 dst_hold(dst); 1996 xdst->route = dst; 1997 1998 dst_copy_metrics(dst1, dst); 1999 2000 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2001 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2002 dst1->lastuse = jiffies; 2003 2004 dst1->input = dst_discard; 2005 dst1->output = xdst_queue_output; 2006 2007 dst_hold(dst); 2008 dst1->child = dst; 2009 dst1->path = dst; 2010 2011 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2012 2013 err = -ENODEV; 2014 dev = dst->dev; 2015 if (!dev) 2016 goto free_dst; 2017 2018 err = xfrm_fill_dst(xdst, dev, fl); 2019 if (err) 2020 goto free_dst; 2021 2022 out: 2023 return xdst; 2024 2025 free_dst: 2026 dst_release(dst1); 2027 xdst = ERR_PTR(err); 2028 goto out; 2029 } 2030 2031 static struct xfrm_dst * 2032 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo) 2033 { 2034 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2035 int num_pols = 0, num_xfrms = 0, err; 2036 struct xfrm_dst *xdst; 2037 2038 /* Resolve policies to use if we couldn't get them from 2039 * previous cache entry */ 2040 num_pols = 1; 2041 pols[0] = xfrm_policy_lookup(net, fl, family, dir); 2042 err = xfrm_expand_policies(fl, family, pols, 2043 &num_pols, &num_xfrms); 2044 if (err < 0) 2045 goto inc_error; 2046 if (num_pols == 0) 2047 return NULL; 2048 if (num_xfrms <= 0) 2049 goto make_dummy_bundle; 2050 2051 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2052 xflo->dst_orig); 2053 if (IS_ERR(xdst)) { 2054 err = PTR_ERR(xdst); 2055 if (err != -EAGAIN) 2056 goto error; 2057 goto make_dummy_bundle; 2058 } else if (xdst == NULL) { 2059 num_xfrms = 0; 2060 goto make_dummy_bundle; 2061 } 2062 2063 return xdst; 2064 2065 make_dummy_bundle: 2066 /* We found policies, but there's no bundles to instantiate: 2067 * either because the policy blocks, has no transformations or 2068 * we could not build template (no xfrm_states).*/ 2069 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2070 if (IS_ERR(xdst)) { 2071 xfrm_pols_put(pols, num_pols); 2072 return ERR_CAST(xdst); 2073 } 2074 xdst->num_pols = num_pols; 2075 xdst->num_xfrms = num_xfrms; 2076 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2077 2078 return xdst; 2079 2080 inc_error: 2081 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2082 error: 2083 xfrm_pols_put(pols, num_pols); 2084 return ERR_PTR(err); 2085 } 2086 2087 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2088 struct dst_entry *dst_orig) 2089 { 2090 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2091 struct dst_entry *ret; 2092 2093 if (!afinfo) { 2094 dst_release(dst_orig); 2095 return ERR_PTR(-EINVAL); 2096 } else { 2097 ret = afinfo->blackhole_route(net, dst_orig); 2098 } 2099 rcu_read_unlock(); 2100 2101 return ret; 2102 } 2103 2104 /* Main function: finds/creates a bundle for given flow. 2105 * 2106 * At the moment we eat a raw IP route. Mostly to speed up lookups 2107 * on interfaces with disabled IPsec. 2108 */ 2109 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 2110 const struct flowi *fl, 2111 const struct sock *sk, int flags) 2112 { 2113 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2114 struct xfrm_dst *xdst; 2115 struct dst_entry *dst, *route; 2116 u16 family = dst_orig->ops->family; 2117 u8 dir = XFRM_POLICY_OUT; 2118 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 2119 2120 dst = NULL; 2121 xdst = NULL; 2122 route = NULL; 2123 2124 sk = sk_const_to_full_sk(sk); 2125 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 2126 num_pols = 1; 2127 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family); 2128 err = xfrm_expand_policies(fl, family, pols, 2129 &num_pols, &num_xfrms); 2130 if (err < 0) 2131 goto dropdst; 2132 2133 if (num_pols) { 2134 if (num_xfrms <= 0) { 2135 drop_pols = num_pols; 2136 goto no_transform; 2137 } 2138 2139 xdst = xfrm_resolve_and_create_bundle( 2140 pols, num_pols, fl, 2141 family, dst_orig); 2142 if (IS_ERR(xdst)) { 2143 xfrm_pols_put(pols, num_pols); 2144 err = PTR_ERR(xdst); 2145 goto dropdst; 2146 } else if (xdst == NULL) { 2147 num_xfrms = 0; 2148 drop_pols = num_pols; 2149 goto no_transform; 2150 } 2151 2152 route = xdst->route; 2153 } 2154 } 2155 2156 if (xdst == NULL) { 2157 struct xfrm_flo xflo; 2158 2159 xflo.dst_orig = dst_orig; 2160 xflo.flags = flags; 2161 2162 /* To accelerate a bit... */ 2163 if ((dst_orig->flags & DST_NOXFRM) || 2164 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 2165 goto nopol; 2166 2167 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo); 2168 if (xdst == NULL) 2169 goto nopol; 2170 if (IS_ERR(xdst)) { 2171 err = PTR_ERR(xdst); 2172 goto dropdst; 2173 } 2174 2175 num_pols = xdst->num_pols; 2176 num_xfrms = xdst->num_xfrms; 2177 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 2178 route = xdst->route; 2179 } 2180 2181 dst = &xdst->u.dst; 2182 if (route == NULL && num_xfrms > 0) { 2183 /* The only case when xfrm_bundle_lookup() returns a 2184 * bundle with null route, is when the template could 2185 * not be resolved. It means policies are there, but 2186 * bundle could not be created, since we don't yet 2187 * have the xfrm_state's. We need to wait for KM to 2188 * negotiate new SA's or bail out with error.*/ 2189 if (net->xfrm.sysctl_larval_drop) { 2190 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2191 err = -EREMOTE; 2192 goto error; 2193 } 2194 2195 err = -EAGAIN; 2196 2197 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2198 goto error; 2199 } 2200 2201 no_transform: 2202 if (num_pols == 0) 2203 goto nopol; 2204 2205 if ((flags & XFRM_LOOKUP_ICMP) && 2206 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 2207 err = -ENOENT; 2208 goto error; 2209 } 2210 2211 for (i = 0; i < num_pols; i++) 2212 pols[i]->curlft.use_time = get_seconds(); 2213 2214 if (num_xfrms < 0) { 2215 /* Prohibit the flow */ 2216 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 2217 err = -EPERM; 2218 goto error; 2219 } else if (num_xfrms > 0) { 2220 /* Flow transformed */ 2221 dst_release(dst_orig); 2222 } else { 2223 /* Flow passes untransformed */ 2224 dst_release(dst); 2225 dst = dst_orig; 2226 } 2227 ok: 2228 xfrm_pols_put(pols, drop_pols); 2229 if (dst && dst->xfrm && 2230 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 2231 dst->flags |= DST_XFRM_TUNNEL; 2232 return dst; 2233 2234 nopol: 2235 if (!(flags & XFRM_LOOKUP_ICMP)) { 2236 dst = dst_orig; 2237 goto ok; 2238 } 2239 err = -ENOENT; 2240 error: 2241 dst_release(dst); 2242 dropdst: 2243 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 2244 dst_release(dst_orig); 2245 xfrm_pols_put(pols, drop_pols); 2246 return ERR_PTR(err); 2247 } 2248 EXPORT_SYMBOL(xfrm_lookup); 2249 2250 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 2251 * Otherwise we may send out blackholed packets. 2252 */ 2253 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 2254 const struct flowi *fl, 2255 const struct sock *sk, int flags) 2256 { 2257 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 2258 flags | XFRM_LOOKUP_QUEUE | 2259 XFRM_LOOKUP_KEEP_DST_REF); 2260 2261 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 2262 return make_blackhole(net, dst_orig->ops->family, dst_orig); 2263 2264 return dst; 2265 } 2266 EXPORT_SYMBOL(xfrm_lookup_route); 2267 2268 static inline int 2269 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 2270 { 2271 struct xfrm_state *x; 2272 2273 if (!skb->sp || idx < 0 || idx >= skb->sp->len) 2274 return 0; 2275 x = skb->sp->xvec[idx]; 2276 if (!x->type->reject) 2277 return 0; 2278 return x->type->reject(x, skb, fl); 2279 } 2280 2281 /* When skb is transformed back to its "native" form, we have to 2282 * check policy restrictions. At the moment we make this in maximally 2283 * stupid way. Shame on me. :-) Of course, connected sockets must 2284 * have policy cached at them. 2285 */ 2286 2287 static inline int 2288 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 2289 unsigned short family) 2290 { 2291 if (xfrm_state_kern(x)) 2292 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 2293 return x->id.proto == tmpl->id.proto && 2294 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 2295 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 2296 x->props.mode == tmpl->mode && 2297 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 2298 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 2299 !(x->props.mode != XFRM_MODE_TRANSPORT && 2300 xfrm_state_addr_cmp(tmpl, x, family)); 2301 } 2302 2303 /* 2304 * 0 or more than 0 is returned when validation is succeeded (either bypass 2305 * because of optional transport mode, or next index of the mathced secpath 2306 * state with the template. 2307 * -1 is returned when no matching template is found. 2308 * Otherwise "-2 - errored_index" is returned. 2309 */ 2310 static inline int 2311 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 2312 unsigned short family) 2313 { 2314 int idx = start; 2315 2316 if (tmpl->optional) { 2317 if (tmpl->mode == XFRM_MODE_TRANSPORT) 2318 return start; 2319 } else 2320 start = -1; 2321 for (; idx < sp->len; idx++) { 2322 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 2323 return ++idx; 2324 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 2325 if (start == -1) 2326 start = -2-idx; 2327 break; 2328 } 2329 } 2330 return start; 2331 } 2332 2333 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 2334 unsigned int family, int reverse) 2335 { 2336 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2337 int err; 2338 2339 if (unlikely(afinfo == NULL)) 2340 return -EAFNOSUPPORT; 2341 2342 afinfo->decode_session(skb, fl, reverse); 2343 err = security_xfrm_decode_session(skb, &fl->flowi_secid); 2344 rcu_read_unlock(); 2345 return err; 2346 } 2347 EXPORT_SYMBOL(__xfrm_decode_session); 2348 2349 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 2350 { 2351 for (; k < sp->len; k++) { 2352 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 2353 *idxp = k; 2354 return 1; 2355 } 2356 } 2357 2358 return 0; 2359 } 2360 2361 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 2362 unsigned short family) 2363 { 2364 struct net *net = dev_net(skb->dev); 2365 struct xfrm_policy *pol; 2366 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2367 int npols = 0; 2368 int xfrm_nr; 2369 int pi; 2370 int reverse; 2371 struct flowi fl; 2372 int xerr_idx = -1; 2373 2374 reverse = dir & ~XFRM_POLICY_MASK; 2375 dir &= XFRM_POLICY_MASK; 2376 2377 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 2378 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 2379 return 0; 2380 } 2381 2382 nf_nat_decode_session(skb, &fl, family); 2383 2384 /* First, check used SA against their selectors. */ 2385 if (skb->sp) { 2386 int i; 2387 2388 for (i = skb->sp->len-1; i >= 0; i--) { 2389 struct xfrm_state *x = skb->sp->xvec[i]; 2390 if (!xfrm_selector_match(&x->sel, &fl, family)) { 2391 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 2392 return 0; 2393 } 2394 } 2395 } 2396 2397 pol = NULL; 2398 sk = sk_to_full_sk(sk); 2399 if (sk && sk->sk_policy[dir]) { 2400 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family); 2401 if (IS_ERR(pol)) { 2402 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2403 return 0; 2404 } 2405 } 2406 2407 if (!pol) 2408 pol = xfrm_policy_lookup(net, &fl, family, dir); 2409 2410 if (IS_ERR(pol)) { 2411 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2412 return 0; 2413 } 2414 2415 if (!pol) { 2416 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) { 2417 xfrm_secpath_reject(xerr_idx, skb, &fl); 2418 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 2419 return 0; 2420 } 2421 return 1; 2422 } 2423 2424 pol->curlft.use_time = get_seconds(); 2425 2426 pols[0] = pol; 2427 npols++; 2428 #ifdef CONFIG_XFRM_SUB_POLICY 2429 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2430 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 2431 &fl, family, 2432 XFRM_POLICY_IN); 2433 if (pols[1]) { 2434 if (IS_ERR(pols[1])) { 2435 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2436 return 0; 2437 } 2438 pols[1]->curlft.use_time = get_seconds(); 2439 npols++; 2440 } 2441 } 2442 #endif 2443 2444 if (pol->action == XFRM_POLICY_ALLOW) { 2445 struct sec_path *sp; 2446 static struct sec_path dummy; 2447 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 2448 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 2449 struct xfrm_tmpl **tpp = tp; 2450 int ti = 0; 2451 int i, k; 2452 2453 if ((sp = skb->sp) == NULL) 2454 sp = &dummy; 2455 2456 for (pi = 0; pi < npols; pi++) { 2457 if (pols[pi] != pol && 2458 pols[pi]->action != XFRM_POLICY_ALLOW) { 2459 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2460 goto reject; 2461 } 2462 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 2463 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 2464 goto reject_error; 2465 } 2466 for (i = 0; i < pols[pi]->xfrm_nr; i++) 2467 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 2468 } 2469 xfrm_nr = ti; 2470 if (npols > 1) { 2471 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 2472 tpp = stp; 2473 } 2474 2475 /* For each tunnel xfrm, find the first matching tmpl. 2476 * For each tmpl before that, find corresponding xfrm. 2477 * Order is _important_. Later we will implement 2478 * some barriers, but at the moment barriers 2479 * are implied between each two transformations. 2480 */ 2481 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 2482 k = xfrm_policy_ok(tpp[i], sp, k, family); 2483 if (k < 0) { 2484 if (k < -1) 2485 /* "-2 - errored_index" returned */ 2486 xerr_idx = -(2+k); 2487 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2488 goto reject; 2489 } 2490 } 2491 2492 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 2493 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2494 goto reject; 2495 } 2496 2497 xfrm_pols_put(pols, npols); 2498 return 1; 2499 } 2500 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2501 2502 reject: 2503 xfrm_secpath_reject(xerr_idx, skb, &fl); 2504 reject_error: 2505 xfrm_pols_put(pols, npols); 2506 return 0; 2507 } 2508 EXPORT_SYMBOL(__xfrm_policy_check); 2509 2510 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 2511 { 2512 struct net *net = dev_net(skb->dev); 2513 struct flowi fl; 2514 struct dst_entry *dst; 2515 int res = 1; 2516 2517 if (xfrm_decode_session(skb, &fl, family) < 0) { 2518 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2519 return 0; 2520 } 2521 2522 skb_dst_force(skb); 2523 2524 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 2525 if (IS_ERR(dst)) { 2526 res = 0; 2527 dst = NULL; 2528 } 2529 skb_dst_set(skb, dst); 2530 return res; 2531 } 2532 EXPORT_SYMBOL(__xfrm_route_forward); 2533 2534 /* Optimize later using cookies and generation ids. */ 2535 2536 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 2537 { 2538 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 2539 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 2540 * get validated by dst_ops->check on every use. We do this 2541 * because when a normal route referenced by an XFRM dst is 2542 * obsoleted we do not go looking around for all parent 2543 * referencing XFRM dsts so that we can invalidate them. It 2544 * is just too much work. Instead we make the checks here on 2545 * every use. For example: 2546 * 2547 * XFRM dst A --> IPv4 dst X 2548 * 2549 * X is the "xdst->route" of A (X is also the "dst->path" of A 2550 * in this example). If X is marked obsolete, "A" will not 2551 * notice. That's what we are validating here via the 2552 * stale_bundle() check. 2553 * 2554 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 2555 * be marked on it. 2556 * This will force stale_bundle() to fail on any xdst bundle with 2557 * this dst linked in it. 2558 */ 2559 if (dst->obsolete < 0 && !stale_bundle(dst)) 2560 return dst; 2561 2562 return NULL; 2563 } 2564 2565 static int stale_bundle(struct dst_entry *dst) 2566 { 2567 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 2568 } 2569 2570 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 2571 { 2572 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { 2573 dst->dev = dev_net(dev)->loopback_dev; 2574 dev_hold(dst->dev); 2575 dev_put(dev); 2576 } 2577 } 2578 EXPORT_SYMBOL(xfrm_dst_ifdown); 2579 2580 static void xfrm_link_failure(struct sk_buff *skb) 2581 { 2582 /* Impossible. Such dst must be popped before reaches point of failure. */ 2583 } 2584 2585 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 2586 { 2587 if (dst) { 2588 if (dst->obsolete) { 2589 dst_release(dst); 2590 dst = NULL; 2591 } 2592 } 2593 return dst; 2594 } 2595 2596 static void xfrm_init_pmtu(struct dst_entry *dst) 2597 { 2598 do { 2599 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2600 u32 pmtu, route_mtu_cached; 2601 2602 pmtu = dst_mtu(dst->child); 2603 xdst->child_mtu_cached = pmtu; 2604 2605 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 2606 2607 route_mtu_cached = dst_mtu(xdst->route); 2608 xdst->route_mtu_cached = route_mtu_cached; 2609 2610 if (pmtu > route_mtu_cached) 2611 pmtu = route_mtu_cached; 2612 2613 dst_metric_set(dst, RTAX_MTU, pmtu); 2614 } while ((dst = dst->next)); 2615 } 2616 2617 /* Check that the bundle accepts the flow and its components are 2618 * still valid. 2619 */ 2620 2621 static int xfrm_bundle_ok(struct xfrm_dst *first) 2622 { 2623 struct dst_entry *dst = &first->u.dst; 2624 struct xfrm_dst *last; 2625 u32 mtu; 2626 2627 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) || 2628 (dst->dev && !netif_running(dst->dev))) 2629 return 0; 2630 2631 if (dst->flags & DST_XFRM_QUEUE) 2632 return 1; 2633 2634 last = NULL; 2635 2636 do { 2637 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2638 2639 if (dst->xfrm->km.state != XFRM_STATE_VALID) 2640 return 0; 2641 if (xdst->xfrm_genid != dst->xfrm->genid) 2642 return 0; 2643 if (xdst->num_pols > 0 && 2644 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 2645 return 0; 2646 2647 mtu = dst_mtu(dst->child); 2648 if (xdst->child_mtu_cached != mtu) { 2649 last = xdst; 2650 xdst->child_mtu_cached = mtu; 2651 } 2652 2653 if (!dst_check(xdst->route, xdst->route_cookie)) 2654 return 0; 2655 mtu = dst_mtu(xdst->route); 2656 if (xdst->route_mtu_cached != mtu) { 2657 last = xdst; 2658 xdst->route_mtu_cached = mtu; 2659 } 2660 2661 dst = dst->child; 2662 } while (dst->xfrm); 2663 2664 if (likely(!last)) 2665 return 1; 2666 2667 mtu = last->child_mtu_cached; 2668 for (;;) { 2669 dst = &last->u.dst; 2670 2671 mtu = xfrm_state_mtu(dst->xfrm, mtu); 2672 if (mtu > last->route_mtu_cached) 2673 mtu = last->route_mtu_cached; 2674 dst_metric_set(dst, RTAX_MTU, mtu); 2675 2676 if (last == first) 2677 break; 2678 2679 last = (struct xfrm_dst *)last->u.dst.next; 2680 last->child_mtu_cached = mtu; 2681 } 2682 2683 return 1; 2684 } 2685 2686 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 2687 { 2688 return dst_metric_advmss(dst->path); 2689 } 2690 2691 static unsigned int xfrm_mtu(const struct dst_entry *dst) 2692 { 2693 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 2694 2695 return mtu ? : dst_mtu(dst->path); 2696 } 2697 2698 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 2699 const void *daddr) 2700 { 2701 const struct dst_entry *path = dst->path; 2702 2703 for (; dst != path; dst = dst->child) { 2704 const struct xfrm_state *xfrm = dst->xfrm; 2705 2706 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 2707 continue; 2708 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 2709 daddr = xfrm->coaddr; 2710 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 2711 daddr = &xfrm->id.daddr; 2712 } 2713 return daddr; 2714 } 2715 2716 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 2717 struct sk_buff *skb, 2718 const void *daddr) 2719 { 2720 const struct dst_entry *path = dst->path; 2721 2722 if (!skb) 2723 daddr = xfrm_get_dst_nexthop(dst, daddr); 2724 return path->ops->neigh_lookup(path, skb, daddr); 2725 } 2726 2727 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 2728 { 2729 const struct dst_entry *path = dst->path; 2730 2731 daddr = xfrm_get_dst_nexthop(dst, daddr); 2732 path->ops->confirm_neigh(path, daddr); 2733 } 2734 2735 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 2736 { 2737 int err = 0; 2738 2739 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 2740 return -EAFNOSUPPORT; 2741 2742 spin_lock(&xfrm_policy_afinfo_lock); 2743 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 2744 err = -EEXIST; 2745 else { 2746 struct dst_ops *dst_ops = afinfo->dst_ops; 2747 if (likely(dst_ops->kmem_cachep == NULL)) 2748 dst_ops->kmem_cachep = xfrm_dst_cache; 2749 if (likely(dst_ops->check == NULL)) 2750 dst_ops->check = xfrm_dst_check; 2751 if (likely(dst_ops->default_advmss == NULL)) 2752 dst_ops->default_advmss = xfrm_default_advmss; 2753 if (likely(dst_ops->mtu == NULL)) 2754 dst_ops->mtu = xfrm_mtu; 2755 if (likely(dst_ops->negative_advice == NULL)) 2756 dst_ops->negative_advice = xfrm_negative_advice; 2757 if (likely(dst_ops->link_failure == NULL)) 2758 dst_ops->link_failure = xfrm_link_failure; 2759 if (likely(dst_ops->neigh_lookup == NULL)) 2760 dst_ops->neigh_lookup = xfrm_neigh_lookup; 2761 if (likely(!dst_ops->confirm_neigh)) 2762 dst_ops->confirm_neigh = xfrm_confirm_neigh; 2763 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 2764 } 2765 spin_unlock(&xfrm_policy_afinfo_lock); 2766 2767 return err; 2768 } 2769 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 2770 2771 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 2772 { 2773 struct dst_ops *dst_ops = afinfo->dst_ops; 2774 int i; 2775 2776 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 2777 if (xfrm_policy_afinfo[i] != afinfo) 2778 continue; 2779 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 2780 break; 2781 } 2782 2783 synchronize_rcu(); 2784 2785 dst_ops->kmem_cachep = NULL; 2786 dst_ops->check = NULL; 2787 dst_ops->negative_advice = NULL; 2788 dst_ops->link_failure = NULL; 2789 } 2790 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 2791 2792 #ifdef CONFIG_XFRM_STATISTICS 2793 static int __net_init xfrm_statistics_init(struct net *net) 2794 { 2795 int rv; 2796 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 2797 if (!net->mib.xfrm_statistics) 2798 return -ENOMEM; 2799 rv = xfrm_proc_init(net); 2800 if (rv < 0) 2801 free_percpu(net->mib.xfrm_statistics); 2802 return rv; 2803 } 2804 2805 static void xfrm_statistics_fini(struct net *net) 2806 { 2807 xfrm_proc_fini(net); 2808 free_percpu(net->mib.xfrm_statistics); 2809 } 2810 #else 2811 static int __net_init xfrm_statistics_init(struct net *net) 2812 { 2813 return 0; 2814 } 2815 2816 static void xfrm_statistics_fini(struct net *net) 2817 { 2818 } 2819 #endif 2820 2821 static int __net_init xfrm_policy_init(struct net *net) 2822 { 2823 unsigned int hmask, sz; 2824 int dir; 2825 2826 if (net_eq(net, &init_net)) 2827 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 2828 sizeof(struct xfrm_dst), 2829 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 2830 NULL); 2831 2832 hmask = 8 - 1; 2833 sz = (hmask+1) * sizeof(struct hlist_head); 2834 2835 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 2836 if (!net->xfrm.policy_byidx) 2837 goto out_byidx; 2838 net->xfrm.policy_idx_hmask = hmask; 2839 2840 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2841 struct xfrm_policy_hash *htab; 2842 2843 net->xfrm.policy_count[dir] = 0; 2844 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 2845 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 2846 2847 htab = &net->xfrm.policy_bydst[dir]; 2848 htab->table = xfrm_hash_alloc(sz); 2849 if (!htab->table) 2850 goto out_bydst; 2851 htab->hmask = hmask; 2852 htab->dbits4 = 32; 2853 htab->sbits4 = 32; 2854 htab->dbits6 = 128; 2855 htab->sbits6 = 128; 2856 } 2857 net->xfrm.policy_hthresh.lbits4 = 32; 2858 net->xfrm.policy_hthresh.rbits4 = 32; 2859 net->xfrm.policy_hthresh.lbits6 = 128; 2860 net->xfrm.policy_hthresh.rbits6 = 128; 2861 2862 seqlock_init(&net->xfrm.policy_hthresh.lock); 2863 2864 INIT_LIST_HEAD(&net->xfrm.policy_all); 2865 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 2866 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 2867 if (net_eq(net, &init_net)) 2868 xfrm_dev_init(); 2869 return 0; 2870 2871 out_bydst: 2872 for (dir--; dir >= 0; dir--) { 2873 struct xfrm_policy_hash *htab; 2874 2875 htab = &net->xfrm.policy_bydst[dir]; 2876 xfrm_hash_free(htab->table, sz); 2877 } 2878 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2879 out_byidx: 2880 return -ENOMEM; 2881 } 2882 2883 static void xfrm_policy_fini(struct net *net) 2884 { 2885 unsigned int sz; 2886 int dir; 2887 2888 flush_work(&net->xfrm.policy_hash_work); 2889 #ifdef CONFIG_XFRM_SUB_POLICY 2890 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 2891 #endif 2892 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 2893 2894 WARN_ON(!list_empty(&net->xfrm.policy_all)); 2895 2896 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2897 struct xfrm_policy_hash *htab; 2898 2899 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 2900 2901 htab = &net->xfrm.policy_bydst[dir]; 2902 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 2903 WARN_ON(!hlist_empty(htab->table)); 2904 xfrm_hash_free(htab->table, sz); 2905 } 2906 2907 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 2908 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 2909 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2910 } 2911 2912 static int __net_init xfrm_net_init(struct net *net) 2913 { 2914 int rv; 2915 2916 /* Initialize the per-net locks here */ 2917 spin_lock_init(&net->xfrm.xfrm_state_lock); 2918 spin_lock_init(&net->xfrm.xfrm_policy_lock); 2919 mutex_init(&net->xfrm.xfrm_cfg_mutex); 2920 2921 rv = xfrm_statistics_init(net); 2922 if (rv < 0) 2923 goto out_statistics; 2924 rv = xfrm_state_init(net); 2925 if (rv < 0) 2926 goto out_state; 2927 rv = xfrm_policy_init(net); 2928 if (rv < 0) 2929 goto out_policy; 2930 rv = xfrm_sysctl_init(net); 2931 if (rv < 0) 2932 goto out_sysctl; 2933 2934 return 0; 2935 2936 out_sysctl: 2937 xfrm_policy_fini(net); 2938 out_policy: 2939 xfrm_state_fini(net); 2940 out_state: 2941 xfrm_statistics_fini(net); 2942 out_statistics: 2943 return rv; 2944 } 2945 2946 static void __net_exit xfrm_net_exit(struct net *net) 2947 { 2948 xfrm_sysctl_fini(net); 2949 xfrm_policy_fini(net); 2950 xfrm_state_fini(net); 2951 xfrm_statistics_fini(net); 2952 } 2953 2954 static struct pernet_operations __net_initdata xfrm_net_ops = { 2955 .init = xfrm_net_init, 2956 .exit = xfrm_net_exit, 2957 }; 2958 2959 void __init xfrm_init(void) 2960 { 2961 int i; 2962 2963 xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work), 2964 GFP_KERNEL); 2965 BUG_ON(!xfrm_pcpu_work); 2966 2967 for (i = 0; i < NR_CPUS; i++) 2968 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn); 2969 2970 register_pernet_subsys(&xfrm_net_ops); 2971 seqcount_init(&xfrm_policy_hash_generation); 2972 xfrm_input_init(); 2973 } 2974 2975 #ifdef CONFIG_AUDITSYSCALL 2976 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 2977 struct audit_buffer *audit_buf) 2978 { 2979 struct xfrm_sec_ctx *ctx = xp->security; 2980 struct xfrm_selector *sel = &xp->selector; 2981 2982 if (ctx) 2983 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 2984 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 2985 2986 switch (sel->family) { 2987 case AF_INET: 2988 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 2989 if (sel->prefixlen_s != 32) 2990 audit_log_format(audit_buf, " src_prefixlen=%d", 2991 sel->prefixlen_s); 2992 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 2993 if (sel->prefixlen_d != 32) 2994 audit_log_format(audit_buf, " dst_prefixlen=%d", 2995 sel->prefixlen_d); 2996 break; 2997 case AF_INET6: 2998 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 2999 if (sel->prefixlen_s != 128) 3000 audit_log_format(audit_buf, " src_prefixlen=%d", 3001 sel->prefixlen_s); 3002 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 3003 if (sel->prefixlen_d != 128) 3004 audit_log_format(audit_buf, " dst_prefixlen=%d", 3005 sel->prefixlen_d); 3006 break; 3007 } 3008 } 3009 3010 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 3011 { 3012 struct audit_buffer *audit_buf; 3013 3014 audit_buf = xfrm_audit_start("SPD-add"); 3015 if (audit_buf == NULL) 3016 return; 3017 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3018 audit_log_format(audit_buf, " res=%u", result); 3019 xfrm_audit_common_policyinfo(xp, audit_buf); 3020 audit_log_end(audit_buf); 3021 } 3022 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 3023 3024 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 3025 bool task_valid) 3026 { 3027 struct audit_buffer *audit_buf; 3028 3029 audit_buf = xfrm_audit_start("SPD-delete"); 3030 if (audit_buf == NULL) 3031 return; 3032 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3033 audit_log_format(audit_buf, " res=%u", result); 3034 xfrm_audit_common_policyinfo(xp, audit_buf); 3035 audit_log_end(audit_buf); 3036 } 3037 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 3038 #endif 3039 3040 #ifdef CONFIG_XFRM_MIGRATE 3041 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 3042 const struct xfrm_selector *sel_tgt) 3043 { 3044 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 3045 if (sel_tgt->family == sel_cmp->family && 3046 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 3047 sel_cmp->family) && 3048 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 3049 sel_cmp->family) && 3050 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 3051 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 3052 return true; 3053 } 3054 } else { 3055 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 3056 return true; 3057 } 3058 } 3059 return false; 3060 } 3061 3062 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 3063 u8 dir, u8 type, struct net *net) 3064 { 3065 struct xfrm_policy *pol, *ret = NULL; 3066 struct hlist_head *chain; 3067 u32 priority = ~0U; 3068 3069 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 3070 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 3071 hlist_for_each_entry(pol, chain, bydst) { 3072 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3073 pol->type == type) { 3074 ret = pol; 3075 priority = ret->priority; 3076 break; 3077 } 3078 } 3079 chain = &net->xfrm.policy_inexact[dir]; 3080 hlist_for_each_entry(pol, chain, bydst) { 3081 if ((pol->priority >= priority) && ret) 3082 break; 3083 3084 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3085 pol->type == type) { 3086 ret = pol; 3087 break; 3088 } 3089 } 3090 3091 xfrm_pol_hold(ret); 3092 3093 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 3094 3095 return ret; 3096 } 3097 3098 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 3099 { 3100 int match = 0; 3101 3102 if (t->mode == m->mode && t->id.proto == m->proto && 3103 (m->reqid == 0 || t->reqid == m->reqid)) { 3104 switch (t->mode) { 3105 case XFRM_MODE_TUNNEL: 3106 case XFRM_MODE_BEET: 3107 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 3108 m->old_family) && 3109 xfrm_addr_equal(&t->saddr, &m->old_saddr, 3110 m->old_family)) { 3111 match = 1; 3112 } 3113 break; 3114 case XFRM_MODE_TRANSPORT: 3115 /* in case of transport mode, template does not store 3116 any IP addresses, hence we just compare mode and 3117 protocol */ 3118 match = 1; 3119 break; 3120 default: 3121 break; 3122 } 3123 } 3124 return match; 3125 } 3126 3127 /* update endpoint address(es) of template(s) */ 3128 static int xfrm_policy_migrate(struct xfrm_policy *pol, 3129 struct xfrm_migrate *m, int num_migrate) 3130 { 3131 struct xfrm_migrate *mp; 3132 int i, j, n = 0; 3133 3134 write_lock_bh(&pol->lock); 3135 if (unlikely(pol->walk.dead)) { 3136 /* target policy has been deleted */ 3137 write_unlock_bh(&pol->lock); 3138 return -ENOENT; 3139 } 3140 3141 for (i = 0; i < pol->xfrm_nr; i++) { 3142 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 3143 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 3144 continue; 3145 n++; 3146 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 3147 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 3148 continue; 3149 /* update endpoints */ 3150 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 3151 sizeof(pol->xfrm_vec[i].id.daddr)); 3152 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 3153 sizeof(pol->xfrm_vec[i].saddr)); 3154 pol->xfrm_vec[i].encap_family = mp->new_family; 3155 /* flush bundles */ 3156 atomic_inc(&pol->genid); 3157 } 3158 } 3159 3160 write_unlock_bh(&pol->lock); 3161 3162 if (!n) 3163 return -ENODATA; 3164 3165 return 0; 3166 } 3167 3168 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 3169 { 3170 int i, j; 3171 3172 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 3173 return -EINVAL; 3174 3175 for (i = 0; i < num_migrate; i++) { 3176 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 3177 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 3178 return -EINVAL; 3179 3180 /* check if there is any duplicated entry */ 3181 for (j = i + 1; j < num_migrate; j++) { 3182 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 3183 sizeof(m[i].old_daddr)) && 3184 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 3185 sizeof(m[i].old_saddr)) && 3186 m[i].proto == m[j].proto && 3187 m[i].mode == m[j].mode && 3188 m[i].reqid == m[j].reqid && 3189 m[i].old_family == m[j].old_family) 3190 return -EINVAL; 3191 } 3192 } 3193 3194 return 0; 3195 } 3196 3197 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 3198 struct xfrm_migrate *m, int num_migrate, 3199 struct xfrm_kmaddress *k, struct net *net, 3200 struct xfrm_encap_tmpl *encap) 3201 { 3202 int i, err, nx_cur = 0, nx_new = 0; 3203 struct xfrm_policy *pol = NULL; 3204 struct xfrm_state *x, *xc; 3205 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 3206 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 3207 struct xfrm_migrate *mp; 3208 3209 /* Stage 0 - sanity checks */ 3210 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 3211 goto out; 3212 3213 if (dir >= XFRM_POLICY_MAX) { 3214 err = -EINVAL; 3215 goto out; 3216 } 3217 3218 /* Stage 1 - find policy */ 3219 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 3220 err = -ENOENT; 3221 goto out; 3222 } 3223 3224 /* Stage 2 - find and update state(s) */ 3225 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 3226 if ((x = xfrm_migrate_state_find(mp, net))) { 3227 x_cur[nx_cur] = x; 3228 nx_cur++; 3229 xc = xfrm_state_migrate(x, mp, encap); 3230 if (xc) { 3231 x_new[nx_new] = xc; 3232 nx_new++; 3233 } else { 3234 err = -ENODATA; 3235 goto restore_state; 3236 } 3237 } 3238 } 3239 3240 /* Stage 3 - update policy */ 3241 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 3242 goto restore_state; 3243 3244 /* Stage 4 - delete old state(s) */ 3245 if (nx_cur) { 3246 xfrm_states_put(x_cur, nx_cur); 3247 xfrm_states_delete(x_cur, nx_cur); 3248 } 3249 3250 /* Stage 5 - announce */ 3251 km_migrate(sel, dir, type, m, num_migrate, k, encap); 3252 3253 xfrm_pol_put(pol); 3254 3255 return 0; 3256 out: 3257 return err; 3258 3259 restore_state: 3260 if (pol) 3261 xfrm_pol_put(pol); 3262 if (nx_cur) 3263 xfrm_states_put(x_cur, nx_cur); 3264 if (nx_new) 3265 xfrm_states_delete(x_new, nx_new); 3266 3267 return err; 3268 } 3269 EXPORT_SYMBOL(xfrm_migrate); 3270 #endif 3271