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 (policy->walk.dead || 613 xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) { 614 /* skip socket policies */ 615 continue; 616 } 617 newpos = NULL; 618 chain = policy_hash_bysel(net, &policy->selector, 619 policy->family, 620 xfrm_policy_id2dir(policy->index)); 621 hlist_for_each_entry(pol, chain, bydst) { 622 if (policy->priority >= pol->priority) 623 newpos = &pol->bydst; 624 else 625 break; 626 } 627 if (newpos) 628 hlist_add_behind(&policy->bydst, newpos); 629 else 630 hlist_add_head(&policy->bydst, chain); 631 } 632 633 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 634 635 mutex_unlock(&hash_resize_mutex); 636 } 637 638 void xfrm_policy_hash_rebuild(struct net *net) 639 { 640 schedule_work(&net->xfrm.policy_hthresh.work); 641 } 642 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 643 644 /* Generate new index... KAME seems to generate them ordered by cost 645 * of an absolute inpredictability of ordering of rules. This will not pass. */ 646 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 647 { 648 static u32 idx_generator; 649 650 for (;;) { 651 struct hlist_head *list; 652 struct xfrm_policy *p; 653 u32 idx; 654 int found; 655 656 if (!index) { 657 idx = (idx_generator | dir); 658 idx_generator += 8; 659 } else { 660 idx = index; 661 index = 0; 662 } 663 664 if (idx == 0) 665 idx = 8; 666 list = net->xfrm.policy_byidx + idx_hash(net, idx); 667 found = 0; 668 hlist_for_each_entry(p, list, byidx) { 669 if (p->index == idx) { 670 found = 1; 671 break; 672 } 673 } 674 if (!found) 675 return idx; 676 } 677 } 678 679 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 680 { 681 u32 *p1 = (u32 *) s1; 682 u32 *p2 = (u32 *) s2; 683 int len = sizeof(struct xfrm_selector) / sizeof(u32); 684 int i; 685 686 for (i = 0; i < len; i++) { 687 if (p1[i] != p2[i]) 688 return 1; 689 } 690 691 return 0; 692 } 693 694 static void xfrm_policy_requeue(struct xfrm_policy *old, 695 struct xfrm_policy *new) 696 { 697 struct xfrm_policy_queue *pq = &old->polq; 698 struct sk_buff_head list; 699 700 if (skb_queue_empty(&pq->hold_queue)) 701 return; 702 703 __skb_queue_head_init(&list); 704 705 spin_lock_bh(&pq->hold_queue.lock); 706 skb_queue_splice_init(&pq->hold_queue, &list); 707 if (del_timer(&pq->hold_timer)) 708 xfrm_pol_put(old); 709 spin_unlock_bh(&pq->hold_queue.lock); 710 711 pq = &new->polq; 712 713 spin_lock_bh(&pq->hold_queue.lock); 714 skb_queue_splice(&list, &pq->hold_queue); 715 pq->timeout = XFRM_QUEUE_TMO_MIN; 716 if (!mod_timer(&pq->hold_timer, jiffies)) 717 xfrm_pol_hold(new); 718 spin_unlock_bh(&pq->hold_queue.lock); 719 } 720 721 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 722 struct xfrm_policy *pol) 723 { 724 u32 mark = policy->mark.v & policy->mark.m; 725 726 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 727 return true; 728 729 if ((mark & pol->mark.m) == pol->mark.v && 730 policy->priority == pol->priority) 731 return true; 732 733 return false; 734 } 735 736 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 737 { 738 struct net *net = xp_net(policy); 739 struct xfrm_policy *pol; 740 struct xfrm_policy *delpol; 741 struct hlist_head *chain; 742 struct hlist_node *newpos; 743 744 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 745 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 746 delpol = NULL; 747 newpos = NULL; 748 hlist_for_each_entry(pol, chain, bydst) { 749 if (pol->type == policy->type && 750 !selector_cmp(&pol->selector, &policy->selector) && 751 xfrm_policy_mark_match(policy, pol) && 752 xfrm_sec_ctx_match(pol->security, policy->security) && 753 !WARN_ON(delpol)) { 754 if (excl) { 755 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 756 return -EEXIST; 757 } 758 delpol = pol; 759 if (policy->priority > pol->priority) 760 continue; 761 } else if (policy->priority >= pol->priority) { 762 newpos = &pol->bydst; 763 continue; 764 } 765 if (delpol) 766 break; 767 } 768 if (newpos) 769 hlist_add_behind(&policy->bydst, newpos); 770 else 771 hlist_add_head(&policy->bydst, chain); 772 __xfrm_policy_link(policy, dir); 773 774 /* After previous checking, family can either be AF_INET or AF_INET6 */ 775 if (policy->family == AF_INET) 776 rt_genid_bump_ipv4(net); 777 else 778 rt_genid_bump_ipv6(net); 779 780 if (delpol) { 781 xfrm_policy_requeue(delpol, policy); 782 __xfrm_policy_unlink(delpol, dir); 783 } 784 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 785 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 786 policy->curlft.add_time = get_seconds(); 787 policy->curlft.use_time = 0; 788 if (!mod_timer(&policy->timer, jiffies + HZ)) 789 xfrm_pol_hold(policy); 790 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 791 792 if (delpol) 793 xfrm_policy_kill(delpol); 794 else if (xfrm_bydst_should_resize(net, dir, NULL)) 795 schedule_work(&net->xfrm.policy_hash_work); 796 797 return 0; 798 } 799 EXPORT_SYMBOL(xfrm_policy_insert); 800 801 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type, 802 int dir, struct xfrm_selector *sel, 803 struct xfrm_sec_ctx *ctx, int delete, 804 int *err) 805 { 806 struct xfrm_policy *pol, *ret; 807 struct hlist_head *chain; 808 809 *err = 0; 810 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 811 chain = policy_hash_bysel(net, sel, sel->family, dir); 812 ret = NULL; 813 hlist_for_each_entry(pol, chain, bydst) { 814 if (pol->type == type && 815 (mark & pol->mark.m) == pol->mark.v && 816 !selector_cmp(sel, &pol->selector) && 817 xfrm_sec_ctx_match(ctx, pol->security)) { 818 xfrm_pol_hold(pol); 819 if (delete) { 820 *err = security_xfrm_policy_delete( 821 pol->security); 822 if (*err) { 823 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 824 return pol; 825 } 826 __xfrm_policy_unlink(pol, dir); 827 } 828 ret = pol; 829 break; 830 } 831 } 832 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 833 834 if (ret && delete) 835 xfrm_policy_kill(ret); 836 return ret; 837 } 838 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 839 840 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type, 841 int dir, u32 id, int delete, int *err) 842 { 843 struct xfrm_policy *pol, *ret; 844 struct hlist_head *chain; 845 846 *err = -ENOENT; 847 if (xfrm_policy_id2dir(id) != dir) 848 return NULL; 849 850 *err = 0; 851 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 852 chain = net->xfrm.policy_byidx + idx_hash(net, id); 853 ret = NULL; 854 hlist_for_each_entry(pol, chain, byidx) { 855 if (pol->type == type && pol->index == id && 856 (mark & pol->mark.m) == pol->mark.v) { 857 xfrm_pol_hold(pol); 858 if (delete) { 859 *err = security_xfrm_policy_delete( 860 pol->security); 861 if (*err) { 862 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 863 return pol; 864 } 865 __xfrm_policy_unlink(pol, dir); 866 } 867 ret = pol; 868 break; 869 } 870 } 871 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 872 873 if (ret && delete) 874 xfrm_policy_kill(ret); 875 return ret; 876 } 877 EXPORT_SYMBOL(xfrm_policy_byid); 878 879 #ifdef CONFIG_SECURITY_NETWORK_XFRM 880 static inline int 881 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 882 { 883 int dir, err = 0; 884 885 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 886 struct xfrm_policy *pol; 887 int i; 888 889 hlist_for_each_entry(pol, 890 &net->xfrm.policy_inexact[dir], bydst) { 891 if (pol->type != type) 892 continue; 893 err = security_xfrm_policy_delete(pol->security); 894 if (err) { 895 xfrm_audit_policy_delete(pol, 0, task_valid); 896 return err; 897 } 898 } 899 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 900 hlist_for_each_entry(pol, 901 net->xfrm.policy_bydst[dir].table + i, 902 bydst) { 903 if (pol->type != type) 904 continue; 905 err = security_xfrm_policy_delete( 906 pol->security); 907 if (err) { 908 xfrm_audit_policy_delete(pol, 0, 909 task_valid); 910 return err; 911 } 912 } 913 } 914 } 915 return err; 916 } 917 #else 918 static inline int 919 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 920 { 921 return 0; 922 } 923 #endif 924 925 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 926 { 927 int dir, err = 0, cnt = 0; 928 929 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 930 931 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 932 if (err) 933 goto out; 934 935 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 936 struct xfrm_policy *pol; 937 int i; 938 939 again1: 940 hlist_for_each_entry(pol, 941 &net->xfrm.policy_inexact[dir], bydst) { 942 if (pol->type != type) 943 continue; 944 __xfrm_policy_unlink(pol, dir); 945 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 946 cnt++; 947 948 xfrm_audit_policy_delete(pol, 1, task_valid); 949 950 xfrm_policy_kill(pol); 951 952 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 953 goto again1; 954 } 955 956 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 957 again2: 958 hlist_for_each_entry(pol, 959 net->xfrm.policy_bydst[dir].table + i, 960 bydst) { 961 if (pol->type != type) 962 continue; 963 __xfrm_policy_unlink(pol, dir); 964 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 965 cnt++; 966 967 xfrm_audit_policy_delete(pol, 1, task_valid); 968 xfrm_policy_kill(pol); 969 970 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 971 goto again2; 972 } 973 } 974 975 } 976 if (!cnt) 977 err = -ESRCH; 978 out: 979 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 980 return err; 981 } 982 EXPORT_SYMBOL(xfrm_policy_flush); 983 984 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 985 int (*func)(struct xfrm_policy *, int, int, void*), 986 void *data) 987 { 988 struct xfrm_policy *pol; 989 struct xfrm_policy_walk_entry *x; 990 int error = 0; 991 992 if (walk->type >= XFRM_POLICY_TYPE_MAX && 993 walk->type != XFRM_POLICY_TYPE_ANY) 994 return -EINVAL; 995 996 if (list_empty(&walk->walk.all) && walk->seq != 0) 997 return 0; 998 999 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1000 if (list_empty(&walk->walk.all)) 1001 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1002 else 1003 x = list_first_entry(&walk->walk.all, 1004 struct xfrm_policy_walk_entry, all); 1005 1006 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1007 if (x->dead) 1008 continue; 1009 pol = container_of(x, struct xfrm_policy, walk); 1010 if (walk->type != XFRM_POLICY_TYPE_ANY && 1011 walk->type != pol->type) 1012 continue; 1013 error = func(pol, xfrm_policy_id2dir(pol->index), 1014 walk->seq, data); 1015 if (error) { 1016 list_move_tail(&walk->walk.all, &x->all); 1017 goto out; 1018 } 1019 walk->seq++; 1020 } 1021 if (walk->seq == 0) { 1022 error = -ENOENT; 1023 goto out; 1024 } 1025 list_del_init(&walk->walk.all); 1026 out: 1027 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1028 return error; 1029 } 1030 EXPORT_SYMBOL(xfrm_policy_walk); 1031 1032 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1033 { 1034 INIT_LIST_HEAD(&walk->walk.all); 1035 walk->walk.dead = 1; 1036 walk->type = type; 1037 walk->seq = 0; 1038 } 1039 EXPORT_SYMBOL(xfrm_policy_walk_init); 1040 1041 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1042 { 1043 if (list_empty(&walk->walk.all)) 1044 return; 1045 1046 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1047 list_del(&walk->walk.all); 1048 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1049 } 1050 EXPORT_SYMBOL(xfrm_policy_walk_done); 1051 1052 /* 1053 * Find policy to apply to this flow. 1054 * 1055 * Returns 0 if policy found, else an -errno. 1056 */ 1057 static int xfrm_policy_match(const struct xfrm_policy *pol, 1058 const struct flowi *fl, 1059 u8 type, u16 family, int dir) 1060 { 1061 const struct xfrm_selector *sel = &pol->selector; 1062 int ret = -ESRCH; 1063 bool match; 1064 1065 if (pol->family != family || 1066 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1067 pol->type != type) 1068 return ret; 1069 1070 match = xfrm_selector_match(sel, fl, family); 1071 if (match) 1072 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1073 dir); 1074 1075 return ret; 1076 } 1077 1078 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 1079 const struct flowi *fl, 1080 u16 family, u8 dir) 1081 { 1082 int err; 1083 struct xfrm_policy *pol, *ret; 1084 const xfrm_address_t *daddr, *saddr; 1085 struct hlist_head *chain; 1086 unsigned int sequence; 1087 u32 priority; 1088 1089 daddr = xfrm_flowi_daddr(fl, family); 1090 saddr = xfrm_flowi_saddr(fl, family); 1091 if (unlikely(!daddr || !saddr)) 1092 return NULL; 1093 1094 rcu_read_lock(); 1095 retry: 1096 do { 1097 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 1098 chain = policy_hash_direct(net, daddr, saddr, family, dir); 1099 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 1100 1101 priority = ~0U; 1102 ret = NULL; 1103 hlist_for_each_entry_rcu(pol, chain, bydst) { 1104 err = xfrm_policy_match(pol, fl, type, family, dir); 1105 if (err) { 1106 if (err == -ESRCH) 1107 continue; 1108 else { 1109 ret = ERR_PTR(err); 1110 goto fail; 1111 } 1112 } else { 1113 ret = pol; 1114 priority = ret->priority; 1115 break; 1116 } 1117 } 1118 chain = &net->xfrm.policy_inexact[dir]; 1119 hlist_for_each_entry_rcu(pol, chain, bydst) { 1120 if ((pol->priority >= priority) && ret) 1121 break; 1122 1123 err = xfrm_policy_match(pol, fl, type, family, dir); 1124 if (err) { 1125 if (err == -ESRCH) 1126 continue; 1127 else { 1128 ret = ERR_PTR(err); 1129 goto fail; 1130 } 1131 } else { 1132 ret = pol; 1133 break; 1134 } 1135 } 1136 1137 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 1138 goto retry; 1139 1140 if (ret && !xfrm_pol_hold_rcu(ret)) 1141 goto retry; 1142 fail: 1143 rcu_read_unlock(); 1144 1145 return ret; 1146 } 1147 1148 static struct xfrm_policy * 1149 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir) 1150 { 1151 #ifdef CONFIG_XFRM_SUB_POLICY 1152 struct xfrm_policy *pol; 1153 1154 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir); 1155 if (pol != NULL) 1156 return pol; 1157 #endif 1158 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir); 1159 } 1160 1161 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 1162 const struct flowi *fl, u16 family) 1163 { 1164 struct xfrm_policy *pol; 1165 1166 rcu_read_lock(); 1167 again: 1168 pol = rcu_dereference(sk->sk_policy[dir]); 1169 if (pol != NULL) { 1170 bool match; 1171 int err = 0; 1172 1173 if (pol->family != family) { 1174 pol = NULL; 1175 goto out; 1176 } 1177 1178 match = xfrm_selector_match(&pol->selector, fl, family); 1179 if (match) { 1180 if ((sk->sk_mark & pol->mark.m) != pol->mark.v) { 1181 pol = NULL; 1182 goto out; 1183 } 1184 err = security_xfrm_policy_lookup(pol->security, 1185 fl->flowi_secid, 1186 dir); 1187 if (!err) { 1188 if (!xfrm_pol_hold_rcu(pol)) 1189 goto again; 1190 } else if (err == -ESRCH) { 1191 pol = NULL; 1192 } else { 1193 pol = ERR_PTR(err); 1194 } 1195 } else 1196 pol = NULL; 1197 } 1198 out: 1199 rcu_read_unlock(); 1200 return pol; 1201 } 1202 1203 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 1204 { 1205 struct net *net = xp_net(pol); 1206 1207 list_add(&pol->walk.all, &net->xfrm.policy_all); 1208 net->xfrm.policy_count[dir]++; 1209 xfrm_pol_hold(pol); 1210 } 1211 1212 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 1213 int dir) 1214 { 1215 struct net *net = xp_net(pol); 1216 1217 if (list_empty(&pol->walk.all)) 1218 return NULL; 1219 1220 /* Socket policies are not hashed. */ 1221 if (!hlist_unhashed(&pol->bydst)) { 1222 hlist_del_rcu(&pol->bydst); 1223 hlist_del(&pol->byidx); 1224 } 1225 1226 list_del_init(&pol->walk.all); 1227 net->xfrm.policy_count[dir]--; 1228 1229 return pol; 1230 } 1231 1232 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 1233 { 1234 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 1235 } 1236 1237 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 1238 { 1239 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 1240 } 1241 1242 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 1243 { 1244 struct net *net = xp_net(pol); 1245 1246 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1247 pol = __xfrm_policy_unlink(pol, dir); 1248 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1249 if (pol) { 1250 xfrm_policy_kill(pol); 1251 return 0; 1252 } 1253 return -ENOENT; 1254 } 1255 EXPORT_SYMBOL(xfrm_policy_delete); 1256 1257 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 1258 { 1259 struct net *net = xp_net(pol); 1260 struct xfrm_policy *old_pol; 1261 1262 #ifdef CONFIG_XFRM_SUB_POLICY 1263 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 1264 return -EINVAL; 1265 #endif 1266 1267 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1268 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 1269 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 1270 if (pol) { 1271 pol->curlft.add_time = get_seconds(); 1272 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 1273 xfrm_sk_policy_link(pol, dir); 1274 } 1275 rcu_assign_pointer(sk->sk_policy[dir], pol); 1276 if (old_pol) { 1277 if (pol) 1278 xfrm_policy_requeue(old_pol, pol); 1279 1280 /* Unlinking succeeds always. This is the only function 1281 * allowed to delete or replace socket policy. 1282 */ 1283 xfrm_sk_policy_unlink(old_pol, dir); 1284 } 1285 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1286 1287 if (old_pol) { 1288 xfrm_policy_kill(old_pol); 1289 } 1290 return 0; 1291 } 1292 1293 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 1294 { 1295 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 1296 struct net *net = xp_net(old); 1297 1298 if (newp) { 1299 newp->selector = old->selector; 1300 if (security_xfrm_policy_clone(old->security, 1301 &newp->security)) { 1302 kfree(newp); 1303 return NULL; /* ENOMEM */ 1304 } 1305 newp->lft = old->lft; 1306 newp->curlft = old->curlft; 1307 newp->mark = old->mark; 1308 newp->action = old->action; 1309 newp->flags = old->flags; 1310 newp->xfrm_nr = old->xfrm_nr; 1311 newp->index = old->index; 1312 newp->type = old->type; 1313 newp->family = old->family; 1314 memcpy(newp->xfrm_vec, old->xfrm_vec, 1315 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 1316 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1317 xfrm_sk_policy_link(newp, dir); 1318 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1319 xfrm_pol_put(newp); 1320 } 1321 return newp; 1322 } 1323 1324 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 1325 { 1326 const struct xfrm_policy *p; 1327 struct xfrm_policy *np; 1328 int i, ret = 0; 1329 1330 rcu_read_lock(); 1331 for (i = 0; i < 2; i++) { 1332 p = rcu_dereference(osk->sk_policy[i]); 1333 if (p) { 1334 np = clone_policy(p, i); 1335 if (unlikely(!np)) { 1336 ret = -ENOMEM; 1337 break; 1338 } 1339 rcu_assign_pointer(sk->sk_policy[i], np); 1340 } 1341 } 1342 rcu_read_unlock(); 1343 return ret; 1344 } 1345 1346 static int 1347 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 1348 xfrm_address_t *remote, unsigned short family, u32 mark) 1349 { 1350 int err; 1351 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1352 1353 if (unlikely(afinfo == NULL)) 1354 return -EINVAL; 1355 err = afinfo->get_saddr(net, oif, local, remote, mark); 1356 rcu_read_unlock(); 1357 return err; 1358 } 1359 1360 /* Resolve list of templates for the flow, given policy. */ 1361 1362 static int 1363 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 1364 struct xfrm_state **xfrm, unsigned short family) 1365 { 1366 struct net *net = xp_net(policy); 1367 int nx; 1368 int i, error; 1369 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 1370 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 1371 xfrm_address_t tmp; 1372 1373 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 1374 struct xfrm_state *x; 1375 xfrm_address_t *remote = daddr; 1376 xfrm_address_t *local = saddr; 1377 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 1378 1379 if (tmpl->mode == XFRM_MODE_TUNNEL || 1380 tmpl->mode == XFRM_MODE_BEET) { 1381 remote = &tmpl->id.daddr; 1382 local = &tmpl->saddr; 1383 if (xfrm_addr_any(local, tmpl->encap_family)) { 1384 error = xfrm_get_saddr(net, fl->flowi_oif, 1385 &tmp, remote, 1386 tmpl->encap_family, 0); 1387 if (error) 1388 goto fail; 1389 local = &tmp; 1390 } 1391 } 1392 1393 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); 1394 1395 if (x && x->km.state == XFRM_STATE_VALID) { 1396 xfrm[nx++] = x; 1397 daddr = remote; 1398 saddr = local; 1399 continue; 1400 } 1401 if (x) { 1402 error = (x->km.state == XFRM_STATE_ERROR ? 1403 -EINVAL : -EAGAIN); 1404 xfrm_state_put(x); 1405 } else if (error == -ESRCH) { 1406 error = -EAGAIN; 1407 } 1408 1409 if (!tmpl->optional) 1410 goto fail; 1411 } 1412 return nx; 1413 1414 fail: 1415 for (nx--; nx >= 0; nx--) 1416 xfrm_state_put(xfrm[nx]); 1417 return error; 1418 } 1419 1420 static int 1421 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 1422 struct xfrm_state **xfrm, unsigned short family) 1423 { 1424 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 1425 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 1426 int cnx = 0; 1427 int error; 1428 int ret; 1429 int i; 1430 1431 for (i = 0; i < npols; i++) { 1432 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 1433 error = -ENOBUFS; 1434 goto fail; 1435 } 1436 1437 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 1438 if (ret < 0) { 1439 error = ret; 1440 goto fail; 1441 } else 1442 cnx += ret; 1443 } 1444 1445 /* found states are sorted for outbound processing */ 1446 if (npols > 1) 1447 xfrm_state_sort(xfrm, tpp, cnx, family); 1448 1449 return cnx; 1450 1451 fail: 1452 for (cnx--; cnx >= 0; cnx--) 1453 xfrm_state_put(tpp[cnx]); 1454 return error; 1455 1456 } 1457 1458 static int xfrm_get_tos(const struct flowi *fl, int family) 1459 { 1460 const struct xfrm_policy_afinfo *afinfo; 1461 int tos = 0; 1462 1463 afinfo = xfrm_policy_get_afinfo(family); 1464 tos = afinfo ? afinfo->get_tos(fl) : 0; 1465 1466 rcu_read_unlock(); 1467 1468 return tos; 1469 } 1470 1471 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 1472 { 1473 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1474 struct dst_ops *dst_ops; 1475 struct xfrm_dst *xdst; 1476 1477 if (!afinfo) 1478 return ERR_PTR(-EINVAL); 1479 1480 switch (family) { 1481 case AF_INET: 1482 dst_ops = &net->xfrm.xfrm4_dst_ops; 1483 break; 1484 #if IS_ENABLED(CONFIG_IPV6) 1485 case AF_INET6: 1486 dst_ops = &net->xfrm.xfrm6_dst_ops; 1487 break; 1488 #endif 1489 default: 1490 BUG(); 1491 } 1492 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 1493 1494 if (likely(xdst)) { 1495 struct dst_entry *dst = &xdst->u.dst; 1496 1497 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 1498 } else 1499 xdst = ERR_PTR(-ENOBUFS); 1500 1501 rcu_read_unlock(); 1502 1503 return xdst; 1504 } 1505 1506 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 1507 int nfheader_len) 1508 { 1509 const struct xfrm_policy_afinfo *afinfo = 1510 xfrm_policy_get_afinfo(dst->ops->family); 1511 int err; 1512 1513 if (!afinfo) 1514 return -EINVAL; 1515 1516 err = afinfo->init_path(path, dst, nfheader_len); 1517 1518 rcu_read_unlock(); 1519 1520 return err; 1521 } 1522 1523 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 1524 const struct flowi *fl) 1525 { 1526 const struct xfrm_policy_afinfo *afinfo = 1527 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 1528 int err; 1529 1530 if (!afinfo) 1531 return -EINVAL; 1532 1533 err = afinfo->fill_dst(xdst, dev, fl); 1534 1535 rcu_read_unlock(); 1536 1537 return err; 1538 } 1539 1540 1541 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 1542 * all the metrics... Shortly, bundle a bundle. 1543 */ 1544 1545 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 1546 struct xfrm_state **xfrm, int nx, 1547 const struct flowi *fl, 1548 struct dst_entry *dst) 1549 { 1550 struct net *net = xp_net(policy); 1551 unsigned long now = jiffies; 1552 struct net_device *dev; 1553 struct xfrm_mode *inner_mode; 1554 struct dst_entry *dst_prev = NULL; 1555 struct dst_entry *dst0 = NULL; 1556 int i = 0; 1557 int err; 1558 int header_len = 0; 1559 int nfheader_len = 0; 1560 int trailer_len = 0; 1561 int tos; 1562 int family = policy->selector.family; 1563 xfrm_address_t saddr, daddr; 1564 1565 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 1566 1567 tos = xfrm_get_tos(fl, family); 1568 1569 dst_hold(dst); 1570 1571 for (; i < nx; i++) { 1572 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 1573 struct dst_entry *dst1 = &xdst->u.dst; 1574 1575 err = PTR_ERR(xdst); 1576 if (IS_ERR(xdst)) { 1577 dst_release(dst); 1578 goto put_states; 1579 } 1580 1581 if (!dst_prev) 1582 dst0 = dst1; 1583 else 1584 /* Ref count is taken during xfrm_alloc_dst() 1585 * No need to do dst_clone() on dst1 1586 */ 1587 dst_prev->child = dst1; 1588 1589 if (xfrm[i]->sel.family == AF_UNSPEC) { 1590 inner_mode = xfrm_ip2inner_mode(xfrm[i], 1591 xfrm_af2proto(family)); 1592 if (!inner_mode) { 1593 err = -EAFNOSUPPORT; 1594 dst_release(dst); 1595 goto put_states; 1596 } 1597 } else 1598 inner_mode = xfrm[i]->inner_mode; 1599 1600 xdst->route = dst; 1601 dst_copy_metrics(dst1, dst); 1602 1603 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 1604 family = xfrm[i]->props.family; 1605 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 1606 &saddr, &daddr, family, 1607 xfrm[i]->props.output_mark); 1608 err = PTR_ERR(dst); 1609 if (IS_ERR(dst)) 1610 goto put_states; 1611 } else 1612 dst_hold(dst); 1613 1614 dst1->xfrm = xfrm[i]; 1615 xdst->xfrm_genid = xfrm[i]->genid; 1616 1617 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1618 dst1->flags |= DST_HOST; 1619 dst1->lastuse = now; 1620 1621 dst1->input = dst_discard; 1622 dst1->output = inner_mode->afinfo->output; 1623 1624 dst1->next = dst_prev; 1625 dst_prev = dst1; 1626 1627 header_len += xfrm[i]->props.header_len; 1628 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 1629 nfheader_len += xfrm[i]->props.header_len; 1630 trailer_len += xfrm[i]->props.trailer_len; 1631 } 1632 1633 dst_prev->child = dst; 1634 dst0->path = dst; 1635 1636 err = -ENODEV; 1637 dev = dst->dev; 1638 if (!dev) 1639 goto free_dst; 1640 1641 xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len); 1642 xfrm_init_pmtu(dst_prev); 1643 1644 for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) { 1645 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev; 1646 1647 err = xfrm_fill_dst(xdst, dev, fl); 1648 if (err) 1649 goto free_dst; 1650 1651 dst_prev->header_len = header_len; 1652 dst_prev->trailer_len = trailer_len; 1653 header_len -= xdst->u.dst.xfrm->props.header_len; 1654 trailer_len -= xdst->u.dst.xfrm->props.trailer_len; 1655 } 1656 1657 out: 1658 return dst0; 1659 1660 put_states: 1661 for (; i < nx; i++) 1662 xfrm_state_put(xfrm[i]); 1663 free_dst: 1664 if (dst0) 1665 dst_release_immediate(dst0); 1666 dst0 = ERR_PTR(err); 1667 goto out; 1668 } 1669 1670 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 1671 struct xfrm_policy **pols, 1672 int *num_pols, int *num_xfrms) 1673 { 1674 int i; 1675 1676 if (*num_pols == 0 || !pols[0]) { 1677 *num_pols = 0; 1678 *num_xfrms = 0; 1679 return 0; 1680 } 1681 if (IS_ERR(pols[0])) 1682 return PTR_ERR(pols[0]); 1683 1684 *num_xfrms = pols[0]->xfrm_nr; 1685 1686 #ifdef CONFIG_XFRM_SUB_POLICY 1687 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 1688 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 1689 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 1690 XFRM_POLICY_TYPE_MAIN, 1691 fl, family, 1692 XFRM_POLICY_OUT); 1693 if (pols[1]) { 1694 if (IS_ERR(pols[1])) { 1695 xfrm_pols_put(pols, *num_pols); 1696 return PTR_ERR(pols[1]); 1697 } 1698 (*num_pols)++; 1699 (*num_xfrms) += pols[1]->xfrm_nr; 1700 } 1701 } 1702 #endif 1703 for (i = 0; i < *num_pols; i++) { 1704 if (pols[i]->action != XFRM_POLICY_ALLOW) { 1705 *num_xfrms = -1; 1706 break; 1707 } 1708 } 1709 1710 return 0; 1711 1712 } 1713 1714 static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old) 1715 { 1716 this_cpu_write(xfrm_last_dst, xdst); 1717 if (old) 1718 dst_release(&old->u.dst); 1719 } 1720 1721 static void __xfrm_pcpu_work_fn(void) 1722 { 1723 struct xfrm_dst *old; 1724 1725 old = this_cpu_read(xfrm_last_dst); 1726 if (old && !xfrm_bundle_ok(old)) 1727 xfrm_last_dst_update(NULL, old); 1728 } 1729 1730 static void xfrm_pcpu_work_fn(struct work_struct *work) 1731 { 1732 local_bh_disable(); 1733 rcu_read_lock(); 1734 __xfrm_pcpu_work_fn(); 1735 rcu_read_unlock(); 1736 local_bh_enable(); 1737 } 1738 1739 void xfrm_policy_cache_flush(void) 1740 { 1741 struct xfrm_dst *old; 1742 bool found = 0; 1743 int cpu; 1744 1745 might_sleep(); 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 = dst->child; 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 *xdst, *old; 1824 struct dst_entry *dst; 1825 int err; 1826 1827 /* Try to instantiate a bundle */ 1828 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 1829 if (err <= 0) { 1830 if (err != 0 && err != -EAGAIN) 1831 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 1832 return ERR_PTR(err); 1833 } 1834 1835 xdst = this_cpu_read(xfrm_last_dst); 1836 if (xdst && 1837 xdst->u.dst.dev == dst_orig->dev && 1838 xdst->num_pols == num_pols && 1839 memcmp(xdst->pols, pols, 1840 sizeof(struct xfrm_policy *) * num_pols) == 0 && 1841 xfrm_xdst_can_reuse(xdst, xfrm, err)) { 1842 dst_hold(&xdst->u.dst); 1843 xfrm_pols_put(pols, num_pols); 1844 while (err > 0) 1845 xfrm_state_put(xfrm[--err]); 1846 return xdst; 1847 } 1848 1849 old = xdst; 1850 1851 dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig); 1852 if (IS_ERR(dst)) { 1853 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 1854 return ERR_CAST(dst); 1855 } 1856 1857 xdst = (struct xfrm_dst *)dst; 1858 xdst->num_xfrms = err; 1859 xdst->num_pols = num_pols; 1860 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 1861 xdst->policy_genid = atomic_read(&pols[0]->genid); 1862 1863 atomic_set(&xdst->u.dst.__refcnt, 2); 1864 xfrm_last_dst_update(xdst, old); 1865 1866 return xdst; 1867 } 1868 1869 static void xfrm_policy_queue_process(struct timer_list *t) 1870 { 1871 struct sk_buff *skb; 1872 struct sock *sk; 1873 struct dst_entry *dst; 1874 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 1875 struct net *net = xp_net(pol); 1876 struct xfrm_policy_queue *pq = &pol->polq; 1877 struct flowi fl; 1878 struct sk_buff_head list; 1879 1880 spin_lock(&pq->hold_queue.lock); 1881 skb = skb_peek(&pq->hold_queue); 1882 if (!skb) { 1883 spin_unlock(&pq->hold_queue.lock); 1884 goto out; 1885 } 1886 dst = skb_dst(skb); 1887 sk = skb->sk; 1888 xfrm_decode_session(skb, &fl, dst->ops->family); 1889 spin_unlock(&pq->hold_queue.lock); 1890 1891 dst_hold(dst->path); 1892 dst = xfrm_lookup(net, dst->path, &fl, sk, 0); 1893 if (IS_ERR(dst)) 1894 goto purge_queue; 1895 1896 if (dst->flags & DST_XFRM_QUEUE) { 1897 dst_release(dst); 1898 1899 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 1900 goto purge_queue; 1901 1902 pq->timeout = pq->timeout << 1; 1903 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 1904 xfrm_pol_hold(pol); 1905 goto out; 1906 } 1907 1908 dst_release(dst); 1909 1910 __skb_queue_head_init(&list); 1911 1912 spin_lock(&pq->hold_queue.lock); 1913 pq->timeout = 0; 1914 skb_queue_splice_init(&pq->hold_queue, &list); 1915 spin_unlock(&pq->hold_queue.lock); 1916 1917 while (!skb_queue_empty(&list)) { 1918 skb = __skb_dequeue(&list); 1919 1920 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 1921 dst_hold(skb_dst(skb)->path); 1922 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0); 1923 if (IS_ERR(dst)) { 1924 kfree_skb(skb); 1925 continue; 1926 } 1927 1928 nf_reset(skb); 1929 skb_dst_drop(skb); 1930 skb_dst_set(skb, dst); 1931 1932 dst_output(net, skb->sk, skb); 1933 } 1934 1935 out: 1936 xfrm_pol_put(pol); 1937 return; 1938 1939 purge_queue: 1940 pq->timeout = 0; 1941 skb_queue_purge(&pq->hold_queue); 1942 xfrm_pol_put(pol); 1943 } 1944 1945 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 1946 { 1947 unsigned long sched_next; 1948 struct dst_entry *dst = skb_dst(skb); 1949 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 1950 struct xfrm_policy *pol = xdst->pols[0]; 1951 struct xfrm_policy_queue *pq = &pol->polq; 1952 1953 if (unlikely(skb_fclone_busy(sk, skb))) { 1954 kfree_skb(skb); 1955 return 0; 1956 } 1957 1958 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 1959 kfree_skb(skb); 1960 return -EAGAIN; 1961 } 1962 1963 skb_dst_force(skb); 1964 1965 spin_lock_bh(&pq->hold_queue.lock); 1966 1967 if (!pq->timeout) 1968 pq->timeout = XFRM_QUEUE_TMO_MIN; 1969 1970 sched_next = jiffies + pq->timeout; 1971 1972 if (del_timer(&pq->hold_timer)) { 1973 if (time_before(pq->hold_timer.expires, sched_next)) 1974 sched_next = pq->hold_timer.expires; 1975 xfrm_pol_put(pol); 1976 } 1977 1978 __skb_queue_tail(&pq->hold_queue, skb); 1979 if (!mod_timer(&pq->hold_timer, sched_next)) 1980 xfrm_pol_hold(pol); 1981 1982 spin_unlock_bh(&pq->hold_queue.lock); 1983 1984 return 0; 1985 } 1986 1987 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 1988 struct xfrm_flo *xflo, 1989 const struct flowi *fl, 1990 int num_xfrms, 1991 u16 family) 1992 { 1993 int err; 1994 struct net_device *dev; 1995 struct dst_entry *dst; 1996 struct dst_entry *dst1; 1997 struct xfrm_dst *xdst; 1998 1999 xdst = xfrm_alloc_dst(net, family); 2000 if (IS_ERR(xdst)) 2001 return xdst; 2002 2003 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 2004 net->xfrm.sysctl_larval_drop || 2005 num_xfrms <= 0) 2006 return xdst; 2007 2008 dst = xflo->dst_orig; 2009 dst1 = &xdst->u.dst; 2010 dst_hold(dst); 2011 xdst->route = dst; 2012 2013 dst_copy_metrics(dst1, dst); 2014 2015 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 2016 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 2017 dst1->lastuse = jiffies; 2018 2019 dst1->input = dst_discard; 2020 dst1->output = xdst_queue_output; 2021 2022 dst_hold(dst); 2023 dst1->child = dst; 2024 dst1->path = dst; 2025 2026 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 2027 2028 err = -ENODEV; 2029 dev = dst->dev; 2030 if (!dev) 2031 goto free_dst; 2032 2033 err = xfrm_fill_dst(xdst, dev, fl); 2034 if (err) 2035 goto free_dst; 2036 2037 out: 2038 return xdst; 2039 2040 free_dst: 2041 dst_release(dst1); 2042 xdst = ERR_PTR(err); 2043 goto out; 2044 } 2045 2046 static struct xfrm_dst * 2047 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo) 2048 { 2049 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2050 int num_pols = 0, num_xfrms = 0, err; 2051 struct xfrm_dst *xdst; 2052 2053 /* Resolve policies to use if we couldn't get them from 2054 * previous cache entry */ 2055 num_pols = 1; 2056 pols[0] = xfrm_policy_lookup(net, fl, family, dir); 2057 err = xfrm_expand_policies(fl, family, pols, 2058 &num_pols, &num_xfrms); 2059 if (err < 0) 2060 goto inc_error; 2061 if (num_pols == 0) 2062 return NULL; 2063 if (num_xfrms <= 0) 2064 goto make_dummy_bundle; 2065 2066 local_bh_disable(); 2067 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 2068 xflo->dst_orig); 2069 local_bh_enable(); 2070 2071 if (IS_ERR(xdst)) { 2072 err = PTR_ERR(xdst); 2073 if (err != -EAGAIN) 2074 goto error; 2075 goto make_dummy_bundle; 2076 } else if (xdst == NULL) { 2077 num_xfrms = 0; 2078 goto make_dummy_bundle; 2079 } 2080 2081 return xdst; 2082 2083 make_dummy_bundle: 2084 /* We found policies, but there's no bundles to instantiate: 2085 * either because the policy blocks, has no transformations or 2086 * we could not build template (no xfrm_states).*/ 2087 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2088 if (IS_ERR(xdst)) { 2089 xfrm_pols_put(pols, num_pols); 2090 return ERR_CAST(xdst); 2091 } 2092 xdst->num_pols = num_pols; 2093 xdst->num_xfrms = num_xfrms; 2094 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2095 2096 return xdst; 2097 2098 inc_error: 2099 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2100 error: 2101 xfrm_pols_put(pols, num_pols); 2102 return ERR_PTR(err); 2103 } 2104 2105 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2106 struct dst_entry *dst_orig) 2107 { 2108 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2109 struct dst_entry *ret; 2110 2111 if (!afinfo) { 2112 dst_release(dst_orig); 2113 return ERR_PTR(-EINVAL); 2114 } else { 2115 ret = afinfo->blackhole_route(net, dst_orig); 2116 } 2117 rcu_read_unlock(); 2118 2119 return ret; 2120 } 2121 2122 /* Main function: finds/creates a bundle for given flow. 2123 * 2124 * At the moment we eat a raw IP route. Mostly to speed up lookups 2125 * on interfaces with disabled IPsec. 2126 */ 2127 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 2128 const struct flowi *fl, 2129 const struct sock *sk, int flags) 2130 { 2131 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2132 struct xfrm_dst *xdst; 2133 struct dst_entry *dst, *route; 2134 u16 family = dst_orig->ops->family; 2135 u8 dir = XFRM_POLICY_OUT; 2136 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 2137 2138 dst = NULL; 2139 xdst = NULL; 2140 route = NULL; 2141 2142 sk = sk_const_to_full_sk(sk); 2143 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 2144 num_pols = 1; 2145 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family); 2146 err = xfrm_expand_policies(fl, family, pols, 2147 &num_pols, &num_xfrms); 2148 if (err < 0) 2149 goto dropdst; 2150 2151 if (num_pols) { 2152 if (num_xfrms <= 0) { 2153 drop_pols = num_pols; 2154 goto no_transform; 2155 } 2156 2157 local_bh_disable(); 2158 xdst = xfrm_resolve_and_create_bundle( 2159 pols, num_pols, fl, 2160 family, dst_orig); 2161 local_bh_enable(); 2162 2163 if (IS_ERR(xdst)) { 2164 xfrm_pols_put(pols, num_pols); 2165 err = PTR_ERR(xdst); 2166 goto dropdst; 2167 } else if (xdst == NULL) { 2168 num_xfrms = 0; 2169 drop_pols = num_pols; 2170 goto no_transform; 2171 } 2172 2173 route = xdst->route; 2174 } 2175 } 2176 2177 if (xdst == NULL) { 2178 struct xfrm_flo xflo; 2179 2180 xflo.dst_orig = dst_orig; 2181 xflo.flags = flags; 2182 2183 /* To accelerate a bit... */ 2184 if ((dst_orig->flags & DST_NOXFRM) || 2185 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 2186 goto nopol; 2187 2188 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo); 2189 if (xdst == NULL) 2190 goto nopol; 2191 if (IS_ERR(xdst)) { 2192 err = PTR_ERR(xdst); 2193 goto dropdst; 2194 } 2195 2196 num_pols = xdst->num_pols; 2197 num_xfrms = xdst->num_xfrms; 2198 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 2199 route = xdst->route; 2200 } 2201 2202 dst = &xdst->u.dst; 2203 if (route == NULL && num_xfrms > 0) { 2204 /* The only case when xfrm_bundle_lookup() returns a 2205 * bundle with null route, is when the template could 2206 * not be resolved. It means policies are there, but 2207 * bundle could not be created, since we don't yet 2208 * have the xfrm_state's. We need to wait for KM to 2209 * negotiate new SA's or bail out with error.*/ 2210 if (net->xfrm.sysctl_larval_drop) { 2211 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2212 err = -EREMOTE; 2213 goto error; 2214 } 2215 2216 err = -EAGAIN; 2217 2218 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2219 goto error; 2220 } 2221 2222 no_transform: 2223 if (num_pols == 0) 2224 goto nopol; 2225 2226 if ((flags & XFRM_LOOKUP_ICMP) && 2227 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 2228 err = -ENOENT; 2229 goto error; 2230 } 2231 2232 for (i = 0; i < num_pols; i++) 2233 pols[i]->curlft.use_time = get_seconds(); 2234 2235 if (num_xfrms < 0) { 2236 /* Prohibit the flow */ 2237 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 2238 err = -EPERM; 2239 goto error; 2240 } else if (num_xfrms > 0) { 2241 /* Flow transformed */ 2242 dst_release(dst_orig); 2243 } else { 2244 /* Flow passes untransformed */ 2245 dst_release(dst); 2246 dst = dst_orig; 2247 } 2248 ok: 2249 xfrm_pols_put(pols, drop_pols); 2250 if (dst && dst->xfrm && 2251 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 2252 dst->flags |= DST_XFRM_TUNNEL; 2253 return dst; 2254 2255 nopol: 2256 if (!(flags & XFRM_LOOKUP_ICMP)) { 2257 dst = dst_orig; 2258 goto ok; 2259 } 2260 err = -ENOENT; 2261 error: 2262 dst_release(dst); 2263 dropdst: 2264 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 2265 dst_release(dst_orig); 2266 xfrm_pols_put(pols, drop_pols); 2267 return ERR_PTR(err); 2268 } 2269 EXPORT_SYMBOL(xfrm_lookup); 2270 2271 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 2272 * Otherwise we may send out blackholed packets. 2273 */ 2274 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 2275 const struct flowi *fl, 2276 const struct sock *sk, int flags) 2277 { 2278 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 2279 flags | XFRM_LOOKUP_QUEUE | 2280 XFRM_LOOKUP_KEEP_DST_REF); 2281 2282 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 2283 return make_blackhole(net, dst_orig->ops->family, dst_orig); 2284 2285 return dst; 2286 } 2287 EXPORT_SYMBOL(xfrm_lookup_route); 2288 2289 static inline int 2290 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 2291 { 2292 struct xfrm_state *x; 2293 2294 if (!skb->sp || idx < 0 || idx >= skb->sp->len) 2295 return 0; 2296 x = skb->sp->xvec[idx]; 2297 if (!x->type->reject) 2298 return 0; 2299 return x->type->reject(x, skb, fl); 2300 } 2301 2302 /* When skb is transformed back to its "native" form, we have to 2303 * check policy restrictions. At the moment we make this in maximally 2304 * stupid way. Shame on me. :-) Of course, connected sockets must 2305 * have policy cached at them. 2306 */ 2307 2308 static inline int 2309 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 2310 unsigned short family) 2311 { 2312 if (xfrm_state_kern(x)) 2313 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 2314 return x->id.proto == tmpl->id.proto && 2315 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 2316 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 2317 x->props.mode == tmpl->mode && 2318 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 2319 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 2320 !(x->props.mode != XFRM_MODE_TRANSPORT && 2321 xfrm_state_addr_cmp(tmpl, x, family)); 2322 } 2323 2324 /* 2325 * 0 or more than 0 is returned when validation is succeeded (either bypass 2326 * because of optional transport mode, or next index of the mathced secpath 2327 * state with the template. 2328 * -1 is returned when no matching template is found. 2329 * Otherwise "-2 - errored_index" is returned. 2330 */ 2331 static inline int 2332 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 2333 unsigned short family) 2334 { 2335 int idx = start; 2336 2337 if (tmpl->optional) { 2338 if (tmpl->mode == XFRM_MODE_TRANSPORT) 2339 return start; 2340 } else 2341 start = -1; 2342 for (; idx < sp->len; idx++) { 2343 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 2344 return ++idx; 2345 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 2346 if (start == -1) 2347 start = -2-idx; 2348 break; 2349 } 2350 } 2351 return start; 2352 } 2353 2354 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 2355 unsigned int family, int reverse) 2356 { 2357 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2358 int err; 2359 2360 if (unlikely(afinfo == NULL)) 2361 return -EAFNOSUPPORT; 2362 2363 afinfo->decode_session(skb, fl, reverse); 2364 err = security_xfrm_decode_session(skb, &fl->flowi_secid); 2365 rcu_read_unlock(); 2366 return err; 2367 } 2368 EXPORT_SYMBOL(__xfrm_decode_session); 2369 2370 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 2371 { 2372 for (; k < sp->len; k++) { 2373 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 2374 *idxp = k; 2375 return 1; 2376 } 2377 } 2378 2379 return 0; 2380 } 2381 2382 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 2383 unsigned short family) 2384 { 2385 struct net *net = dev_net(skb->dev); 2386 struct xfrm_policy *pol; 2387 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2388 int npols = 0; 2389 int xfrm_nr; 2390 int pi; 2391 int reverse; 2392 struct flowi fl; 2393 int xerr_idx = -1; 2394 2395 reverse = dir & ~XFRM_POLICY_MASK; 2396 dir &= XFRM_POLICY_MASK; 2397 2398 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 2399 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 2400 return 0; 2401 } 2402 2403 nf_nat_decode_session(skb, &fl, family); 2404 2405 /* First, check used SA against their selectors. */ 2406 if (skb->sp) { 2407 int i; 2408 2409 for (i = skb->sp->len-1; i >= 0; i--) { 2410 struct xfrm_state *x = skb->sp->xvec[i]; 2411 if (!xfrm_selector_match(&x->sel, &fl, family)) { 2412 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 2413 return 0; 2414 } 2415 } 2416 } 2417 2418 pol = NULL; 2419 sk = sk_to_full_sk(sk); 2420 if (sk && sk->sk_policy[dir]) { 2421 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family); 2422 if (IS_ERR(pol)) { 2423 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2424 return 0; 2425 } 2426 } 2427 2428 if (!pol) 2429 pol = xfrm_policy_lookup(net, &fl, family, dir); 2430 2431 if (IS_ERR(pol)) { 2432 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2433 return 0; 2434 } 2435 2436 if (!pol) { 2437 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) { 2438 xfrm_secpath_reject(xerr_idx, skb, &fl); 2439 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 2440 return 0; 2441 } 2442 return 1; 2443 } 2444 2445 pol->curlft.use_time = get_seconds(); 2446 2447 pols[0] = pol; 2448 npols++; 2449 #ifdef CONFIG_XFRM_SUB_POLICY 2450 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2451 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 2452 &fl, family, 2453 XFRM_POLICY_IN); 2454 if (pols[1]) { 2455 if (IS_ERR(pols[1])) { 2456 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2457 return 0; 2458 } 2459 pols[1]->curlft.use_time = get_seconds(); 2460 npols++; 2461 } 2462 } 2463 #endif 2464 2465 if (pol->action == XFRM_POLICY_ALLOW) { 2466 struct sec_path *sp; 2467 static struct sec_path dummy; 2468 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 2469 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 2470 struct xfrm_tmpl **tpp = tp; 2471 int ti = 0; 2472 int i, k; 2473 2474 if ((sp = skb->sp) == NULL) 2475 sp = &dummy; 2476 2477 for (pi = 0; pi < npols; pi++) { 2478 if (pols[pi] != pol && 2479 pols[pi]->action != XFRM_POLICY_ALLOW) { 2480 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2481 goto reject; 2482 } 2483 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 2484 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 2485 goto reject_error; 2486 } 2487 for (i = 0; i < pols[pi]->xfrm_nr; i++) 2488 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 2489 } 2490 xfrm_nr = ti; 2491 if (npols > 1) { 2492 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 2493 tpp = stp; 2494 } 2495 2496 /* For each tunnel xfrm, find the first matching tmpl. 2497 * For each tmpl before that, find corresponding xfrm. 2498 * Order is _important_. Later we will implement 2499 * some barriers, but at the moment barriers 2500 * are implied between each two transformations. 2501 */ 2502 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 2503 k = xfrm_policy_ok(tpp[i], sp, k, family); 2504 if (k < 0) { 2505 if (k < -1) 2506 /* "-2 - errored_index" returned */ 2507 xerr_idx = -(2+k); 2508 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2509 goto reject; 2510 } 2511 } 2512 2513 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 2514 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2515 goto reject; 2516 } 2517 2518 xfrm_pols_put(pols, npols); 2519 return 1; 2520 } 2521 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2522 2523 reject: 2524 xfrm_secpath_reject(xerr_idx, skb, &fl); 2525 reject_error: 2526 xfrm_pols_put(pols, npols); 2527 return 0; 2528 } 2529 EXPORT_SYMBOL(__xfrm_policy_check); 2530 2531 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 2532 { 2533 struct net *net = dev_net(skb->dev); 2534 struct flowi fl; 2535 struct dst_entry *dst; 2536 int res = 1; 2537 2538 if (xfrm_decode_session(skb, &fl, family) < 0) { 2539 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2540 return 0; 2541 } 2542 2543 skb_dst_force(skb); 2544 2545 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 2546 if (IS_ERR(dst)) { 2547 res = 0; 2548 dst = NULL; 2549 } 2550 skb_dst_set(skb, dst); 2551 return res; 2552 } 2553 EXPORT_SYMBOL(__xfrm_route_forward); 2554 2555 /* Optimize later using cookies and generation ids. */ 2556 2557 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 2558 { 2559 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 2560 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 2561 * get validated by dst_ops->check on every use. We do this 2562 * because when a normal route referenced by an XFRM dst is 2563 * obsoleted we do not go looking around for all parent 2564 * referencing XFRM dsts so that we can invalidate them. It 2565 * is just too much work. Instead we make the checks here on 2566 * every use. For example: 2567 * 2568 * XFRM dst A --> IPv4 dst X 2569 * 2570 * X is the "xdst->route" of A (X is also the "dst->path" of A 2571 * in this example). If X is marked obsolete, "A" will not 2572 * notice. That's what we are validating here via the 2573 * stale_bundle() check. 2574 * 2575 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 2576 * be marked on it. 2577 * This will force stale_bundle() to fail on any xdst bundle with 2578 * this dst linked in it. 2579 */ 2580 if (dst->obsolete < 0 && !stale_bundle(dst)) 2581 return dst; 2582 2583 return NULL; 2584 } 2585 2586 static int stale_bundle(struct dst_entry *dst) 2587 { 2588 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 2589 } 2590 2591 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 2592 { 2593 while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { 2594 dst->dev = dev_net(dev)->loopback_dev; 2595 dev_hold(dst->dev); 2596 dev_put(dev); 2597 } 2598 } 2599 EXPORT_SYMBOL(xfrm_dst_ifdown); 2600 2601 static void xfrm_link_failure(struct sk_buff *skb) 2602 { 2603 /* Impossible. Such dst must be popped before reaches point of failure. */ 2604 } 2605 2606 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 2607 { 2608 if (dst) { 2609 if (dst->obsolete) { 2610 dst_release(dst); 2611 dst = NULL; 2612 } 2613 } 2614 return dst; 2615 } 2616 2617 static void xfrm_init_pmtu(struct dst_entry *dst) 2618 { 2619 do { 2620 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2621 u32 pmtu, route_mtu_cached; 2622 2623 pmtu = dst_mtu(dst->child); 2624 xdst->child_mtu_cached = pmtu; 2625 2626 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 2627 2628 route_mtu_cached = dst_mtu(xdst->route); 2629 xdst->route_mtu_cached = route_mtu_cached; 2630 2631 if (pmtu > route_mtu_cached) 2632 pmtu = route_mtu_cached; 2633 2634 dst_metric_set(dst, RTAX_MTU, pmtu); 2635 } while ((dst = dst->next)); 2636 } 2637 2638 /* Check that the bundle accepts the flow and its components are 2639 * still valid. 2640 */ 2641 2642 static int xfrm_bundle_ok(struct xfrm_dst *first) 2643 { 2644 struct dst_entry *dst = &first->u.dst; 2645 struct xfrm_dst *last; 2646 u32 mtu; 2647 2648 if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) || 2649 (dst->dev && !netif_running(dst->dev))) 2650 return 0; 2651 2652 if (dst->flags & DST_XFRM_QUEUE) 2653 return 1; 2654 2655 last = NULL; 2656 2657 do { 2658 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2659 2660 if (dst->xfrm->km.state != XFRM_STATE_VALID) 2661 return 0; 2662 if (xdst->xfrm_genid != dst->xfrm->genid) 2663 return 0; 2664 if (xdst->num_pols > 0 && 2665 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 2666 return 0; 2667 2668 mtu = dst_mtu(dst->child); 2669 if (xdst->child_mtu_cached != mtu) { 2670 last = xdst; 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 last = xdst; 2679 xdst->route_mtu_cached = mtu; 2680 } 2681 2682 dst = dst->child; 2683 } while (dst->xfrm); 2684 2685 if (likely(!last)) 2686 return 1; 2687 2688 mtu = last->child_mtu_cached; 2689 for (;;) { 2690 dst = &last->u.dst; 2691 2692 mtu = xfrm_state_mtu(dst->xfrm, mtu); 2693 if (mtu > last->route_mtu_cached) 2694 mtu = last->route_mtu_cached; 2695 dst_metric_set(dst, RTAX_MTU, mtu); 2696 2697 if (last == first) 2698 break; 2699 2700 last = (struct xfrm_dst *)last->u.dst.next; 2701 last->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(dst->path); 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(dst->path); 2717 } 2718 2719 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 2720 const void *daddr) 2721 { 2722 const struct dst_entry *path = dst->path; 2723 2724 for (; dst != path; dst = dst->child) { 2725 const struct xfrm_state *xfrm = dst->xfrm; 2726 2727 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 2728 continue; 2729 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 2730 daddr = xfrm->coaddr; 2731 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 2732 daddr = &xfrm->id.daddr; 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 = dst->path; 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 = dst->path; 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