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_SPINLOCK(xfrm_if_cb_lock); 49 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; 50 51 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); 52 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] 53 __read_mostly; 54 55 static struct kmem_cache *xfrm_dst_cache __ro_after_init; 56 static __read_mostly seqcount_t xfrm_policy_hash_generation; 57 58 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); 59 static int stale_bundle(struct dst_entry *dst); 60 static int xfrm_bundle_ok(struct xfrm_dst *xdst); 61 static void xfrm_policy_queue_process(struct timer_list *t); 62 63 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); 64 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 65 int dir); 66 67 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy) 68 { 69 return refcount_inc_not_zero(&policy->refcnt); 70 } 71 72 static inline bool 73 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 74 { 75 const struct flowi4 *fl4 = &fl->u.ip4; 76 77 return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) && 78 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) && 79 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) && 80 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) && 81 (fl4->flowi4_proto == sel->proto || !sel->proto) && 82 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex); 83 } 84 85 static inline bool 86 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl) 87 { 88 const struct flowi6 *fl6 = &fl->u.ip6; 89 90 return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) && 91 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) && 92 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) && 93 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) && 94 (fl6->flowi6_proto == sel->proto || !sel->proto) && 95 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex); 96 } 97 98 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl, 99 unsigned short family) 100 { 101 switch (family) { 102 case AF_INET: 103 return __xfrm4_selector_match(sel, fl); 104 case AF_INET6: 105 return __xfrm6_selector_match(sel, fl); 106 } 107 return false; 108 } 109 110 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) 111 { 112 const struct xfrm_policy_afinfo *afinfo; 113 114 if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 115 return NULL; 116 rcu_read_lock(); 117 afinfo = rcu_dereference(xfrm_policy_afinfo[family]); 118 if (unlikely(!afinfo)) 119 rcu_read_unlock(); 120 return afinfo; 121 } 122 123 /* Called with rcu_read_lock(). */ 124 static const struct xfrm_if_cb *xfrm_if_get_cb(void) 125 { 126 return rcu_dereference(xfrm_if_cb); 127 } 128 129 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif, 130 const xfrm_address_t *saddr, 131 const xfrm_address_t *daddr, 132 int family, u32 mark) 133 { 134 const struct xfrm_policy_afinfo *afinfo; 135 struct dst_entry *dst; 136 137 afinfo = xfrm_policy_get_afinfo(family); 138 if (unlikely(afinfo == NULL)) 139 return ERR_PTR(-EAFNOSUPPORT); 140 141 dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark); 142 143 rcu_read_unlock(); 144 145 return dst; 146 } 147 EXPORT_SYMBOL(__xfrm_dst_lookup); 148 149 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, 150 int tos, int oif, 151 xfrm_address_t *prev_saddr, 152 xfrm_address_t *prev_daddr, 153 int family, u32 mark) 154 { 155 struct net *net = xs_net(x); 156 xfrm_address_t *saddr = &x->props.saddr; 157 xfrm_address_t *daddr = &x->id.daddr; 158 struct dst_entry *dst; 159 160 if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) { 161 saddr = x->coaddr; 162 daddr = prev_daddr; 163 } 164 if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) { 165 saddr = prev_saddr; 166 daddr = x->coaddr; 167 } 168 169 dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark); 170 171 if (!IS_ERR(dst)) { 172 if (prev_saddr != saddr) 173 memcpy(prev_saddr, saddr, sizeof(*prev_saddr)); 174 if (prev_daddr != daddr) 175 memcpy(prev_daddr, daddr, sizeof(*prev_daddr)); 176 } 177 178 return dst; 179 } 180 181 static inline unsigned long make_jiffies(long secs) 182 { 183 if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ) 184 return MAX_SCHEDULE_TIMEOUT-1; 185 else 186 return secs*HZ; 187 } 188 189 static void xfrm_policy_timer(struct timer_list *t) 190 { 191 struct xfrm_policy *xp = from_timer(xp, t, timer); 192 time64_t now = ktime_get_real_seconds(); 193 time64_t next = TIME64_MAX; 194 int warn = 0; 195 int dir; 196 197 read_lock(&xp->lock); 198 199 if (unlikely(xp->walk.dead)) 200 goto out; 201 202 dir = xfrm_policy_id2dir(xp->index); 203 204 if (xp->lft.hard_add_expires_seconds) { 205 time64_t tmo = xp->lft.hard_add_expires_seconds + 206 xp->curlft.add_time - now; 207 if (tmo <= 0) 208 goto expired; 209 if (tmo < next) 210 next = tmo; 211 } 212 if (xp->lft.hard_use_expires_seconds) { 213 time64_t tmo = xp->lft.hard_use_expires_seconds + 214 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 215 if (tmo <= 0) 216 goto expired; 217 if (tmo < next) 218 next = tmo; 219 } 220 if (xp->lft.soft_add_expires_seconds) { 221 time64_t tmo = xp->lft.soft_add_expires_seconds + 222 xp->curlft.add_time - now; 223 if (tmo <= 0) { 224 warn = 1; 225 tmo = XFRM_KM_TIMEOUT; 226 } 227 if (tmo < next) 228 next = tmo; 229 } 230 if (xp->lft.soft_use_expires_seconds) { 231 time64_t tmo = xp->lft.soft_use_expires_seconds + 232 (xp->curlft.use_time ? : xp->curlft.add_time) - now; 233 if (tmo <= 0) { 234 warn = 1; 235 tmo = XFRM_KM_TIMEOUT; 236 } 237 if (tmo < next) 238 next = tmo; 239 } 240 241 if (warn) 242 km_policy_expired(xp, dir, 0, 0); 243 if (next != TIME64_MAX && 244 !mod_timer(&xp->timer, jiffies + make_jiffies(next))) 245 xfrm_pol_hold(xp); 246 247 out: 248 read_unlock(&xp->lock); 249 xfrm_pol_put(xp); 250 return; 251 252 expired: 253 read_unlock(&xp->lock); 254 if (!xfrm_policy_delete(xp, dir)) 255 km_policy_expired(xp, dir, 1, 0); 256 xfrm_pol_put(xp); 257 } 258 259 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2 260 * SPD calls. 261 */ 262 263 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp) 264 { 265 struct xfrm_policy *policy; 266 267 policy = kzalloc(sizeof(struct xfrm_policy), gfp); 268 269 if (policy) { 270 write_pnet(&policy->xp_net, net); 271 INIT_LIST_HEAD(&policy->walk.all); 272 INIT_HLIST_NODE(&policy->bydst); 273 INIT_HLIST_NODE(&policy->byidx); 274 rwlock_init(&policy->lock); 275 refcount_set(&policy->refcnt, 1); 276 skb_queue_head_init(&policy->polq.hold_queue); 277 timer_setup(&policy->timer, xfrm_policy_timer, 0); 278 timer_setup(&policy->polq.hold_timer, 279 xfrm_policy_queue_process, 0); 280 } 281 return policy; 282 } 283 EXPORT_SYMBOL(xfrm_policy_alloc); 284 285 static void xfrm_policy_destroy_rcu(struct rcu_head *head) 286 { 287 struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu); 288 289 security_xfrm_policy_free(policy->security); 290 kfree(policy); 291 } 292 293 /* Destroy xfrm_policy: descendant resources must be released to this moment. */ 294 295 void xfrm_policy_destroy(struct xfrm_policy *policy) 296 { 297 BUG_ON(!policy->walk.dead); 298 299 if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer)) 300 BUG(); 301 302 call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); 303 } 304 EXPORT_SYMBOL(xfrm_policy_destroy); 305 306 /* Rule must be locked. Release descendant resources, announce 307 * entry dead. The rule must be unlinked from lists to the moment. 308 */ 309 310 static void xfrm_policy_kill(struct xfrm_policy *policy) 311 { 312 policy->walk.dead = 1; 313 314 atomic_inc(&policy->genid); 315 316 if (del_timer(&policy->polq.hold_timer)) 317 xfrm_pol_put(policy); 318 skb_queue_purge(&policy->polq.hold_queue); 319 320 if (del_timer(&policy->timer)) 321 xfrm_pol_put(policy); 322 323 xfrm_pol_put(policy); 324 } 325 326 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; 327 328 static inline unsigned int idx_hash(struct net *net, u32 index) 329 { 330 return __idx_hash(index, net->xfrm.policy_idx_hmask); 331 } 332 333 /* calculate policy hash thresholds */ 334 static void __get_hash_thresh(struct net *net, 335 unsigned short family, int dir, 336 u8 *dbits, u8 *sbits) 337 { 338 switch (family) { 339 case AF_INET: 340 *dbits = net->xfrm.policy_bydst[dir].dbits4; 341 *sbits = net->xfrm.policy_bydst[dir].sbits4; 342 break; 343 344 case AF_INET6: 345 *dbits = net->xfrm.policy_bydst[dir].dbits6; 346 *sbits = net->xfrm.policy_bydst[dir].sbits6; 347 break; 348 349 default: 350 *dbits = 0; 351 *sbits = 0; 352 } 353 } 354 355 static struct hlist_head *policy_hash_bysel(struct net *net, 356 const struct xfrm_selector *sel, 357 unsigned short family, int dir) 358 { 359 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 360 unsigned int hash; 361 u8 dbits; 362 u8 sbits; 363 364 __get_hash_thresh(net, family, dir, &dbits, &sbits); 365 hash = __sel_hash(sel, family, hmask, dbits, sbits); 366 367 if (hash == hmask + 1) 368 return &net->xfrm.policy_inexact[dir]; 369 370 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 371 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 372 } 373 374 static struct hlist_head *policy_hash_direct(struct net *net, 375 const xfrm_address_t *daddr, 376 const xfrm_address_t *saddr, 377 unsigned short family, int dir) 378 { 379 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 380 unsigned int hash; 381 u8 dbits; 382 u8 sbits; 383 384 __get_hash_thresh(net, family, dir, &dbits, &sbits); 385 hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); 386 387 return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, 388 lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; 389 } 390 391 static void xfrm_dst_hash_transfer(struct net *net, 392 struct hlist_head *list, 393 struct hlist_head *ndsttable, 394 unsigned int nhashmask, 395 int dir) 396 { 397 struct hlist_node *tmp, *entry0 = NULL; 398 struct xfrm_policy *pol; 399 unsigned int h0 = 0; 400 u8 dbits; 401 u8 sbits; 402 403 redo: 404 hlist_for_each_entry_safe(pol, tmp, list, bydst) { 405 unsigned int h; 406 407 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); 408 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, 409 pol->family, nhashmask, dbits, sbits); 410 if (!entry0) { 411 hlist_del_rcu(&pol->bydst); 412 hlist_add_head_rcu(&pol->bydst, ndsttable + h); 413 h0 = h; 414 } else { 415 if (h != h0) 416 continue; 417 hlist_del_rcu(&pol->bydst); 418 hlist_add_behind_rcu(&pol->bydst, entry0); 419 } 420 entry0 = &pol->bydst; 421 } 422 if (!hlist_empty(list)) { 423 entry0 = NULL; 424 goto redo; 425 } 426 } 427 428 static void xfrm_idx_hash_transfer(struct hlist_head *list, 429 struct hlist_head *nidxtable, 430 unsigned int nhashmask) 431 { 432 struct hlist_node *tmp; 433 struct xfrm_policy *pol; 434 435 hlist_for_each_entry_safe(pol, tmp, list, byidx) { 436 unsigned int h; 437 438 h = __idx_hash(pol->index, nhashmask); 439 hlist_add_head(&pol->byidx, nidxtable+h); 440 } 441 } 442 443 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) 444 { 445 return ((old_hmask + 1) << 1) - 1; 446 } 447 448 static void xfrm_bydst_resize(struct net *net, int dir) 449 { 450 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 451 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 452 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 453 struct hlist_head *ndst = xfrm_hash_alloc(nsize); 454 struct hlist_head *odst; 455 int i; 456 457 if (!ndst) 458 return; 459 460 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 461 write_seqcount_begin(&xfrm_policy_hash_generation); 462 463 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 464 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 465 466 odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, 467 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 468 469 for (i = hmask; i >= 0; i--) 470 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); 471 472 rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); 473 net->xfrm.policy_bydst[dir].hmask = nhashmask; 474 475 write_seqcount_end(&xfrm_policy_hash_generation); 476 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 477 478 synchronize_rcu(); 479 480 xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); 481 } 482 483 static void xfrm_byidx_resize(struct net *net, int total) 484 { 485 unsigned int hmask = net->xfrm.policy_idx_hmask; 486 unsigned int nhashmask = xfrm_new_hash_mask(hmask); 487 unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); 488 struct hlist_head *oidx = net->xfrm.policy_byidx; 489 struct hlist_head *nidx = xfrm_hash_alloc(nsize); 490 int i; 491 492 if (!nidx) 493 return; 494 495 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 496 497 for (i = hmask; i >= 0; i--) 498 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); 499 500 net->xfrm.policy_byidx = nidx; 501 net->xfrm.policy_idx_hmask = nhashmask; 502 503 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 504 505 xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); 506 } 507 508 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) 509 { 510 unsigned int cnt = net->xfrm.policy_count[dir]; 511 unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; 512 513 if (total) 514 *total += cnt; 515 516 if ((hmask + 1) < xfrm_policy_hashmax && 517 cnt > hmask) 518 return 1; 519 520 return 0; 521 } 522 523 static inline int xfrm_byidx_should_resize(struct net *net, int total) 524 { 525 unsigned int hmask = net->xfrm.policy_idx_hmask; 526 527 if ((hmask + 1) < xfrm_policy_hashmax && 528 total > hmask) 529 return 1; 530 531 return 0; 532 } 533 534 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) 535 { 536 si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; 537 si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; 538 si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; 539 si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; 540 si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; 541 si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; 542 si->spdhcnt = net->xfrm.policy_idx_hmask; 543 si->spdhmcnt = xfrm_policy_hashmax; 544 } 545 EXPORT_SYMBOL(xfrm_spd_getinfo); 546 547 static DEFINE_MUTEX(hash_resize_mutex); 548 static void xfrm_hash_resize(struct work_struct *work) 549 { 550 struct net *net = container_of(work, struct net, xfrm.policy_hash_work); 551 int dir, total; 552 553 mutex_lock(&hash_resize_mutex); 554 555 total = 0; 556 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 557 if (xfrm_bydst_should_resize(net, dir, &total)) 558 xfrm_bydst_resize(net, dir); 559 } 560 if (xfrm_byidx_should_resize(net, total)) 561 xfrm_byidx_resize(net, total); 562 563 mutex_unlock(&hash_resize_mutex); 564 } 565 566 static void xfrm_hash_rebuild(struct work_struct *work) 567 { 568 struct net *net = container_of(work, struct net, 569 xfrm.policy_hthresh.work); 570 unsigned int hmask; 571 struct xfrm_policy *pol; 572 struct xfrm_policy *policy; 573 struct hlist_head *chain; 574 struct hlist_head *odst; 575 struct hlist_node *newpos; 576 int i; 577 int dir; 578 unsigned seq; 579 u8 lbits4, rbits4, lbits6, rbits6; 580 581 mutex_lock(&hash_resize_mutex); 582 583 /* read selector prefixlen thresholds */ 584 do { 585 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock); 586 587 lbits4 = net->xfrm.policy_hthresh.lbits4; 588 rbits4 = net->xfrm.policy_hthresh.rbits4; 589 lbits6 = net->xfrm.policy_hthresh.lbits6; 590 rbits6 = net->xfrm.policy_hthresh.rbits6; 591 } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); 592 593 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 594 595 /* reset the bydst and inexact table in all directions */ 596 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 597 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 598 hmask = net->xfrm.policy_bydst[dir].hmask; 599 odst = net->xfrm.policy_bydst[dir].table; 600 for (i = hmask; i >= 0; i--) 601 INIT_HLIST_HEAD(odst + i); 602 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) { 603 /* dir out => dst = remote, src = local */ 604 net->xfrm.policy_bydst[dir].dbits4 = rbits4; 605 net->xfrm.policy_bydst[dir].sbits4 = lbits4; 606 net->xfrm.policy_bydst[dir].dbits6 = rbits6; 607 net->xfrm.policy_bydst[dir].sbits6 = lbits6; 608 } else { 609 /* dir in/fwd => dst = local, src = remote */ 610 net->xfrm.policy_bydst[dir].dbits4 = lbits4; 611 net->xfrm.policy_bydst[dir].sbits4 = rbits4; 612 net->xfrm.policy_bydst[dir].dbits6 = lbits6; 613 net->xfrm.policy_bydst[dir].sbits6 = rbits6; 614 } 615 } 616 617 /* re-insert all policies by order of creation */ 618 list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { 619 if (policy->walk.dead || 620 xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) { 621 /* skip socket policies */ 622 continue; 623 } 624 newpos = NULL; 625 chain = policy_hash_bysel(net, &policy->selector, 626 policy->family, 627 xfrm_policy_id2dir(policy->index)); 628 hlist_for_each_entry(pol, chain, bydst) { 629 if (policy->priority >= pol->priority) 630 newpos = &pol->bydst; 631 else 632 break; 633 } 634 if (newpos) 635 hlist_add_behind(&policy->bydst, newpos); 636 else 637 hlist_add_head(&policy->bydst, chain); 638 } 639 640 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 641 642 mutex_unlock(&hash_resize_mutex); 643 } 644 645 void xfrm_policy_hash_rebuild(struct net *net) 646 { 647 schedule_work(&net->xfrm.policy_hthresh.work); 648 } 649 EXPORT_SYMBOL(xfrm_policy_hash_rebuild); 650 651 /* Generate new index... KAME seems to generate them ordered by cost 652 * of an absolute inpredictability of ordering of rules. This will not pass. */ 653 static u32 xfrm_gen_index(struct net *net, int dir, u32 index) 654 { 655 static u32 idx_generator; 656 657 for (;;) { 658 struct hlist_head *list; 659 struct xfrm_policy *p; 660 u32 idx; 661 int found; 662 663 if (!index) { 664 idx = (idx_generator | dir); 665 idx_generator += 8; 666 } else { 667 idx = index; 668 index = 0; 669 } 670 671 if (idx == 0) 672 idx = 8; 673 list = net->xfrm.policy_byidx + idx_hash(net, idx); 674 found = 0; 675 hlist_for_each_entry(p, list, byidx) { 676 if (p->index == idx) { 677 found = 1; 678 break; 679 } 680 } 681 if (!found) 682 return idx; 683 } 684 } 685 686 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) 687 { 688 u32 *p1 = (u32 *) s1; 689 u32 *p2 = (u32 *) s2; 690 int len = sizeof(struct xfrm_selector) / sizeof(u32); 691 int i; 692 693 for (i = 0; i < len; i++) { 694 if (p1[i] != p2[i]) 695 return 1; 696 } 697 698 return 0; 699 } 700 701 static void xfrm_policy_requeue(struct xfrm_policy *old, 702 struct xfrm_policy *new) 703 { 704 struct xfrm_policy_queue *pq = &old->polq; 705 struct sk_buff_head list; 706 707 if (skb_queue_empty(&pq->hold_queue)) 708 return; 709 710 __skb_queue_head_init(&list); 711 712 spin_lock_bh(&pq->hold_queue.lock); 713 skb_queue_splice_init(&pq->hold_queue, &list); 714 if (del_timer(&pq->hold_timer)) 715 xfrm_pol_put(old); 716 spin_unlock_bh(&pq->hold_queue.lock); 717 718 pq = &new->polq; 719 720 spin_lock_bh(&pq->hold_queue.lock); 721 skb_queue_splice(&list, &pq->hold_queue); 722 pq->timeout = XFRM_QUEUE_TMO_MIN; 723 if (!mod_timer(&pq->hold_timer, jiffies)) 724 xfrm_pol_hold(new); 725 spin_unlock_bh(&pq->hold_queue.lock); 726 } 727 728 static bool xfrm_policy_mark_match(struct xfrm_policy *policy, 729 struct xfrm_policy *pol) 730 { 731 u32 mark = policy->mark.v & policy->mark.m; 732 733 if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m) 734 return true; 735 736 if ((mark & pol->mark.m) == pol->mark.v && 737 policy->priority == pol->priority) 738 return true; 739 740 return false; 741 } 742 743 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) 744 { 745 struct net *net = xp_net(policy); 746 struct xfrm_policy *pol; 747 struct xfrm_policy *delpol; 748 struct hlist_head *chain; 749 struct hlist_node *newpos; 750 751 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 752 chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); 753 delpol = NULL; 754 newpos = NULL; 755 hlist_for_each_entry(pol, chain, bydst) { 756 if (pol->type == policy->type && 757 pol->if_id == policy->if_id && 758 !selector_cmp(&pol->selector, &policy->selector) && 759 xfrm_policy_mark_match(policy, pol) && 760 xfrm_sec_ctx_match(pol->security, policy->security) && 761 !WARN_ON(delpol)) { 762 if (excl) { 763 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 764 return -EEXIST; 765 } 766 delpol = pol; 767 if (policy->priority > pol->priority) 768 continue; 769 } else if (policy->priority >= pol->priority) { 770 newpos = &pol->bydst; 771 continue; 772 } 773 if (delpol) 774 break; 775 } 776 if (newpos) 777 hlist_add_behind(&policy->bydst, newpos); 778 else 779 hlist_add_head(&policy->bydst, chain); 780 __xfrm_policy_link(policy, dir); 781 782 /* After previous checking, family can either be AF_INET or AF_INET6 */ 783 if (policy->family == AF_INET) 784 rt_genid_bump_ipv4(net); 785 else 786 rt_genid_bump_ipv6(net); 787 788 if (delpol) { 789 xfrm_policy_requeue(delpol, policy); 790 __xfrm_policy_unlink(delpol, dir); 791 } 792 policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); 793 hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); 794 policy->curlft.add_time = ktime_get_real_seconds(); 795 policy->curlft.use_time = 0; 796 if (!mod_timer(&policy->timer, jiffies + HZ)) 797 xfrm_pol_hold(policy); 798 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 799 800 if (delpol) 801 xfrm_policy_kill(delpol); 802 else if (xfrm_bydst_should_resize(net, dir, NULL)) 803 schedule_work(&net->xfrm.policy_hash_work); 804 805 return 0; 806 } 807 EXPORT_SYMBOL(xfrm_policy_insert); 808 809 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id, 810 u8 type, int dir, 811 struct xfrm_selector *sel, 812 struct xfrm_sec_ctx *ctx, int delete, 813 int *err) 814 { 815 struct xfrm_policy *pol, *ret; 816 struct hlist_head *chain; 817 818 *err = 0; 819 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 820 chain = policy_hash_bysel(net, sel, sel->family, dir); 821 ret = NULL; 822 hlist_for_each_entry(pol, chain, bydst) { 823 if (pol->type == type && 824 pol->if_id == if_id && 825 (mark & pol->mark.m) == pol->mark.v && 826 !selector_cmp(sel, &pol->selector) && 827 xfrm_sec_ctx_match(ctx, pol->security)) { 828 xfrm_pol_hold(pol); 829 if (delete) { 830 *err = security_xfrm_policy_delete( 831 pol->security); 832 if (*err) { 833 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 834 return pol; 835 } 836 __xfrm_policy_unlink(pol, dir); 837 } 838 ret = pol; 839 break; 840 } 841 } 842 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 843 844 if (ret && delete) 845 xfrm_policy_kill(ret); 846 return ret; 847 } 848 EXPORT_SYMBOL(xfrm_policy_bysel_ctx); 849 850 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id, 851 u8 type, int dir, u32 id, int delete, 852 int *err) 853 { 854 struct xfrm_policy *pol, *ret; 855 struct hlist_head *chain; 856 857 *err = -ENOENT; 858 if (xfrm_policy_id2dir(id) != dir) 859 return NULL; 860 861 *err = 0; 862 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 863 chain = net->xfrm.policy_byidx + idx_hash(net, id); 864 ret = NULL; 865 hlist_for_each_entry(pol, chain, byidx) { 866 if (pol->type == type && pol->index == id && 867 pol->if_id == if_id && 868 (mark & pol->mark.m) == pol->mark.v) { 869 xfrm_pol_hold(pol); 870 if (delete) { 871 *err = security_xfrm_policy_delete( 872 pol->security); 873 if (*err) { 874 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 875 return pol; 876 } 877 __xfrm_policy_unlink(pol, dir); 878 } 879 ret = pol; 880 break; 881 } 882 } 883 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 884 885 if (ret && delete) 886 xfrm_policy_kill(ret); 887 return ret; 888 } 889 EXPORT_SYMBOL(xfrm_policy_byid); 890 891 #ifdef CONFIG_SECURITY_NETWORK_XFRM 892 static inline int 893 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 894 { 895 int dir, err = 0; 896 897 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 898 struct xfrm_policy *pol; 899 int i; 900 901 hlist_for_each_entry(pol, 902 &net->xfrm.policy_inexact[dir], bydst) { 903 if (pol->type != type) 904 continue; 905 err = security_xfrm_policy_delete(pol->security); 906 if (err) { 907 xfrm_audit_policy_delete(pol, 0, task_valid); 908 return err; 909 } 910 } 911 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 912 hlist_for_each_entry(pol, 913 net->xfrm.policy_bydst[dir].table + i, 914 bydst) { 915 if (pol->type != type) 916 continue; 917 err = security_xfrm_policy_delete( 918 pol->security); 919 if (err) { 920 xfrm_audit_policy_delete(pol, 0, 921 task_valid); 922 return err; 923 } 924 } 925 } 926 } 927 return err; 928 } 929 #else 930 static inline int 931 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) 932 { 933 return 0; 934 } 935 #endif 936 937 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) 938 { 939 int dir, err = 0, cnt = 0; 940 941 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 942 943 err = xfrm_policy_flush_secctx_check(net, type, task_valid); 944 if (err) 945 goto out; 946 947 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 948 struct xfrm_policy *pol; 949 int i; 950 951 again1: 952 hlist_for_each_entry(pol, 953 &net->xfrm.policy_inexact[dir], bydst) { 954 if (pol->type != type) 955 continue; 956 __xfrm_policy_unlink(pol, dir); 957 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 958 cnt++; 959 960 xfrm_audit_policy_delete(pol, 1, task_valid); 961 962 xfrm_policy_kill(pol); 963 964 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 965 goto again1; 966 } 967 968 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) { 969 again2: 970 hlist_for_each_entry(pol, 971 net->xfrm.policy_bydst[dir].table + i, 972 bydst) { 973 if (pol->type != type) 974 continue; 975 __xfrm_policy_unlink(pol, dir); 976 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 977 cnt++; 978 979 xfrm_audit_policy_delete(pol, 1, task_valid); 980 xfrm_policy_kill(pol); 981 982 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 983 goto again2; 984 } 985 } 986 987 } 988 if (!cnt) 989 err = -ESRCH; 990 out: 991 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 992 return err; 993 } 994 EXPORT_SYMBOL(xfrm_policy_flush); 995 996 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, 997 int (*func)(struct xfrm_policy *, int, int, void*), 998 void *data) 999 { 1000 struct xfrm_policy *pol; 1001 struct xfrm_policy_walk_entry *x; 1002 int error = 0; 1003 1004 if (walk->type >= XFRM_POLICY_TYPE_MAX && 1005 walk->type != XFRM_POLICY_TYPE_ANY) 1006 return -EINVAL; 1007 1008 if (list_empty(&walk->walk.all) && walk->seq != 0) 1009 return 0; 1010 1011 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1012 if (list_empty(&walk->walk.all)) 1013 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); 1014 else 1015 x = list_first_entry(&walk->walk.all, 1016 struct xfrm_policy_walk_entry, all); 1017 1018 list_for_each_entry_from(x, &net->xfrm.policy_all, all) { 1019 if (x->dead) 1020 continue; 1021 pol = container_of(x, struct xfrm_policy, walk); 1022 if (walk->type != XFRM_POLICY_TYPE_ANY && 1023 walk->type != pol->type) 1024 continue; 1025 error = func(pol, xfrm_policy_id2dir(pol->index), 1026 walk->seq, data); 1027 if (error) { 1028 list_move_tail(&walk->walk.all, &x->all); 1029 goto out; 1030 } 1031 walk->seq++; 1032 } 1033 if (walk->seq == 0) { 1034 error = -ENOENT; 1035 goto out; 1036 } 1037 list_del_init(&walk->walk.all); 1038 out: 1039 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1040 return error; 1041 } 1042 EXPORT_SYMBOL(xfrm_policy_walk); 1043 1044 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) 1045 { 1046 INIT_LIST_HEAD(&walk->walk.all); 1047 walk->walk.dead = 1; 1048 walk->type = type; 1049 walk->seq = 0; 1050 } 1051 EXPORT_SYMBOL(xfrm_policy_walk_init); 1052 1053 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) 1054 { 1055 if (list_empty(&walk->walk.all)) 1056 return; 1057 1058 spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ 1059 list_del(&walk->walk.all); 1060 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1061 } 1062 EXPORT_SYMBOL(xfrm_policy_walk_done); 1063 1064 /* 1065 * Find policy to apply to this flow. 1066 * 1067 * Returns 0 if policy found, else an -errno. 1068 */ 1069 static int xfrm_policy_match(const struct xfrm_policy *pol, 1070 const struct flowi *fl, 1071 u8 type, u16 family, int dir, u32 if_id) 1072 { 1073 const struct xfrm_selector *sel = &pol->selector; 1074 int ret = -ESRCH; 1075 bool match; 1076 1077 if (pol->family != family || 1078 pol->if_id != if_id || 1079 (fl->flowi_mark & pol->mark.m) != pol->mark.v || 1080 pol->type != type) 1081 return ret; 1082 1083 match = xfrm_selector_match(sel, fl, family); 1084 if (match) 1085 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, 1086 dir); 1087 1088 return ret; 1089 } 1090 1091 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, 1092 const struct flowi *fl, 1093 u16 family, u8 dir, 1094 u32 if_id) 1095 { 1096 int err; 1097 struct xfrm_policy *pol, *ret; 1098 const xfrm_address_t *daddr, *saddr; 1099 struct hlist_head *chain; 1100 unsigned int sequence; 1101 u32 priority; 1102 1103 daddr = xfrm_flowi_daddr(fl, family); 1104 saddr = xfrm_flowi_saddr(fl, family); 1105 if (unlikely(!daddr || !saddr)) 1106 return NULL; 1107 1108 rcu_read_lock(); 1109 retry: 1110 do { 1111 sequence = read_seqcount_begin(&xfrm_policy_hash_generation); 1112 chain = policy_hash_direct(net, daddr, saddr, family, dir); 1113 } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)); 1114 1115 priority = ~0U; 1116 ret = NULL; 1117 hlist_for_each_entry_rcu(pol, chain, bydst) { 1118 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 1119 if (err) { 1120 if (err == -ESRCH) 1121 continue; 1122 else { 1123 ret = ERR_PTR(err); 1124 goto fail; 1125 } 1126 } else { 1127 ret = pol; 1128 priority = ret->priority; 1129 break; 1130 } 1131 } 1132 chain = &net->xfrm.policy_inexact[dir]; 1133 hlist_for_each_entry_rcu(pol, chain, bydst) { 1134 if ((pol->priority >= priority) && ret) 1135 break; 1136 1137 err = xfrm_policy_match(pol, fl, type, family, dir, if_id); 1138 if (err) { 1139 if (err == -ESRCH) 1140 continue; 1141 else { 1142 ret = ERR_PTR(err); 1143 goto fail; 1144 } 1145 } else { 1146 ret = pol; 1147 break; 1148 } 1149 } 1150 1151 if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence)) 1152 goto retry; 1153 1154 if (ret && !xfrm_pol_hold_rcu(ret)) 1155 goto retry; 1156 fail: 1157 rcu_read_unlock(); 1158 1159 return ret; 1160 } 1161 1162 static struct xfrm_policy *xfrm_policy_lookup(struct net *net, 1163 const struct flowi *fl, 1164 u16 family, u8 dir, u32 if_id) 1165 { 1166 #ifdef CONFIG_XFRM_SUB_POLICY 1167 struct xfrm_policy *pol; 1168 1169 pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, 1170 dir, if_id); 1171 if (pol != NULL) 1172 return pol; 1173 #endif 1174 return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, 1175 dir, if_id); 1176 } 1177 1178 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, 1179 const struct flowi *fl, 1180 u16 family, u32 if_id) 1181 { 1182 struct xfrm_policy *pol; 1183 1184 rcu_read_lock(); 1185 again: 1186 pol = rcu_dereference(sk->sk_policy[dir]); 1187 if (pol != NULL) { 1188 bool match; 1189 int err = 0; 1190 1191 if (pol->family != family) { 1192 pol = NULL; 1193 goto out; 1194 } 1195 1196 match = xfrm_selector_match(&pol->selector, fl, family); 1197 if (match) { 1198 if ((sk->sk_mark & pol->mark.m) != pol->mark.v || 1199 pol->if_id != if_id) { 1200 pol = NULL; 1201 goto out; 1202 } 1203 err = security_xfrm_policy_lookup(pol->security, 1204 fl->flowi_secid, 1205 dir); 1206 if (!err) { 1207 if (!xfrm_pol_hold_rcu(pol)) 1208 goto again; 1209 } else if (err == -ESRCH) { 1210 pol = NULL; 1211 } else { 1212 pol = ERR_PTR(err); 1213 } 1214 } else 1215 pol = NULL; 1216 } 1217 out: 1218 rcu_read_unlock(); 1219 return pol; 1220 } 1221 1222 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) 1223 { 1224 struct net *net = xp_net(pol); 1225 1226 list_add(&pol->walk.all, &net->xfrm.policy_all); 1227 net->xfrm.policy_count[dir]++; 1228 xfrm_pol_hold(pol); 1229 } 1230 1231 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, 1232 int dir) 1233 { 1234 struct net *net = xp_net(pol); 1235 1236 if (list_empty(&pol->walk.all)) 1237 return NULL; 1238 1239 /* Socket policies are not hashed. */ 1240 if (!hlist_unhashed(&pol->bydst)) { 1241 hlist_del_rcu(&pol->bydst); 1242 hlist_del(&pol->byidx); 1243 } 1244 1245 list_del_init(&pol->walk.all); 1246 net->xfrm.policy_count[dir]--; 1247 1248 return pol; 1249 } 1250 1251 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir) 1252 { 1253 __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir); 1254 } 1255 1256 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir) 1257 { 1258 __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir); 1259 } 1260 1261 int xfrm_policy_delete(struct xfrm_policy *pol, int dir) 1262 { 1263 struct net *net = xp_net(pol); 1264 1265 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1266 pol = __xfrm_policy_unlink(pol, dir); 1267 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1268 if (pol) { 1269 xfrm_policy_kill(pol); 1270 return 0; 1271 } 1272 return -ENOENT; 1273 } 1274 EXPORT_SYMBOL(xfrm_policy_delete); 1275 1276 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol) 1277 { 1278 struct net *net = sock_net(sk); 1279 struct xfrm_policy *old_pol; 1280 1281 #ifdef CONFIG_XFRM_SUB_POLICY 1282 if (pol && pol->type != XFRM_POLICY_TYPE_MAIN) 1283 return -EINVAL; 1284 #endif 1285 1286 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1287 old_pol = rcu_dereference_protected(sk->sk_policy[dir], 1288 lockdep_is_held(&net->xfrm.xfrm_policy_lock)); 1289 if (pol) { 1290 pol->curlft.add_time = ktime_get_real_seconds(); 1291 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0); 1292 xfrm_sk_policy_link(pol, dir); 1293 } 1294 rcu_assign_pointer(sk->sk_policy[dir], pol); 1295 if (old_pol) { 1296 if (pol) 1297 xfrm_policy_requeue(old_pol, pol); 1298 1299 /* Unlinking succeeds always. This is the only function 1300 * allowed to delete or replace socket policy. 1301 */ 1302 xfrm_sk_policy_unlink(old_pol, dir); 1303 } 1304 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1305 1306 if (old_pol) { 1307 xfrm_policy_kill(old_pol); 1308 } 1309 return 0; 1310 } 1311 1312 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir) 1313 { 1314 struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC); 1315 struct net *net = xp_net(old); 1316 1317 if (newp) { 1318 newp->selector = old->selector; 1319 if (security_xfrm_policy_clone(old->security, 1320 &newp->security)) { 1321 kfree(newp); 1322 return NULL; /* ENOMEM */ 1323 } 1324 newp->lft = old->lft; 1325 newp->curlft = old->curlft; 1326 newp->mark = old->mark; 1327 newp->if_id = old->if_id; 1328 newp->action = old->action; 1329 newp->flags = old->flags; 1330 newp->xfrm_nr = old->xfrm_nr; 1331 newp->index = old->index; 1332 newp->type = old->type; 1333 newp->family = old->family; 1334 memcpy(newp->xfrm_vec, old->xfrm_vec, 1335 newp->xfrm_nr*sizeof(struct xfrm_tmpl)); 1336 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 1337 xfrm_sk_policy_link(newp, dir); 1338 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 1339 xfrm_pol_put(newp); 1340 } 1341 return newp; 1342 } 1343 1344 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk) 1345 { 1346 const struct xfrm_policy *p; 1347 struct xfrm_policy *np; 1348 int i, ret = 0; 1349 1350 rcu_read_lock(); 1351 for (i = 0; i < 2; i++) { 1352 p = rcu_dereference(osk->sk_policy[i]); 1353 if (p) { 1354 np = clone_policy(p, i); 1355 if (unlikely(!np)) { 1356 ret = -ENOMEM; 1357 break; 1358 } 1359 rcu_assign_pointer(sk->sk_policy[i], np); 1360 } 1361 } 1362 rcu_read_unlock(); 1363 return ret; 1364 } 1365 1366 static int 1367 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local, 1368 xfrm_address_t *remote, unsigned short family, u32 mark) 1369 { 1370 int err; 1371 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1372 1373 if (unlikely(afinfo == NULL)) 1374 return -EINVAL; 1375 err = afinfo->get_saddr(net, oif, local, remote, mark); 1376 rcu_read_unlock(); 1377 return err; 1378 } 1379 1380 /* Resolve list of templates for the flow, given policy. */ 1381 1382 static int 1383 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl, 1384 struct xfrm_state **xfrm, unsigned short family) 1385 { 1386 struct net *net = xp_net(policy); 1387 int nx; 1388 int i, error; 1389 xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); 1390 xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); 1391 xfrm_address_t tmp; 1392 1393 for (nx = 0, i = 0; i < policy->xfrm_nr; i++) { 1394 struct xfrm_state *x; 1395 xfrm_address_t *remote = daddr; 1396 xfrm_address_t *local = saddr; 1397 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i]; 1398 1399 if (tmpl->mode == XFRM_MODE_TUNNEL || 1400 tmpl->mode == XFRM_MODE_BEET) { 1401 remote = &tmpl->id.daddr; 1402 local = &tmpl->saddr; 1403 if (xfrm_addr_any(local, tmpl->encap_family)) { 1404 error = xfrm_get_saddr(net, fl->flowi_oif, 1405 &tmp, remote, 1406 tmpl->encap_family, 0); 1407 if (error) 1408 goto fail; 1409 local = &tmp; 1410 } 1411 } 1412 1413 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, 1414 family, policy->if_id); 1415 1416 if (x && x->km.state == XFRM_STATE_VALID) { 1417 xfrm[nx++] = x; 1418 daddr = remote; 1419 saddr = local; 1420 continue; 1421 } 1422 if (x) { 1423 error = (x->km.state == XFRM_STATE_ERROR ? 1424 -EINVAL : -EAGAIN); 1425 xfrm_state_put(x); 1426 } else if (error == -ESRCH) { 1427 error = -EAGAIN; 1428 } 1429 1430 if (!tmpl->optional) 1431 goto fail; 1432 } 1433 return nx; 1434 1435 fail: 1436 for (nx--; nx >= 0; nx--) 1437 xfrm_state_put(xfrm[nx]); 1438 return error; 1439 } 1440 1441 static int 1442 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl, 1443 struct xfrm_state **xfrm, unsigned short family) 1444 { 1445 struct xfrm_state *tp[XFRM_MAX_DEPTH]; 1446 struct xfrm_state **tpp = (npols > 1) ? tp : xfrm; 1447 int cnx = 0; 1448 int error; 1449 int ret; 1450 int i; 1451 1452 for (i = 0; i < npols; i++) { 1453 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) { 1454 error = -ENOBUFS; 1455 goto fail; 1456 } 1457 1458 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family); 1459 if (ret < 0) { 1460 error = ret; 1461 goto fail; 1462 } else 1463 cnx += ret; 1464 } 1465 1466 /* found states are sorted for outbound processing */ 1467 if (npols > 1) 1468 xfrm_state_sort(xfrm, tpp, cnx, family); 1469 1470 return cnx; 1471 1472 fail: 1473 for (cnx--; cnx >= 0; cnx--) 1474 xfrm_state_put(tpp[cnx]); 1475 return error; 1476 1477 } 1478 1479 static int xfrm_get_tos(const struct flowi *fl, int family) 1480 { 1481 const struct xfrm_policy_afinfo *afinfo; 1482 int tos; 1483 1484 afinfo = xfrm_policy_get_afinfo(family); 1485 if (!afinfo) 1486 return 0; 1487 1488 tos = afinfo->get_tos(fl); 1489 1490 rcu_read_unlock(); 1491 1492 return tos; 1493 } 1494 1495 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) 1496 { 1497 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 1498 struct dst_ops *dst_ops; 1499 struct xfrm_dst *xdst; 1500 1501 if (!afinfo) 1502 return ERR_PTR(-EINVAL); 1503 1504 switch (family) { 1505 case AF_INET: 1506 dst_ops = &net->xfrm.xfrm4_dst_ops; 1507 break; 1508 #if IS_ENABLED(CONFIG_IPV6) 1509 case AF_INET6: 1510 dst_ops = &net->xfrm.xfrm6_dst_ops; 1511 break; 1512 #endif 1513 default: 1514 BUG(); 1515 } 1516 xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); 1517 1518 if (likely(xdst)) { 1519 struct dst_entry *dst = &xdst->u.dst; 1520 1521 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); 1522 } else 1523 xdst = ERR_PTR(-ENOBUFS); 1524 1525 rcu_read_unlock(); 1526 1527 return xdst; 1528 } 1529 1530 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst, 1531 int nfheader_len) 1532 { 1533 const struct xfrm_policy_afinfo *afinfo = 1534 xfrm_policy_get_afinfo(dst->ops->family); 1535 int err; 1536 1537 if (!afinfo) 1538 return -EINVAL; 1539 1540 err = afinfo->init_path(path, dst, nfheader_len); 1541 1542 rcu_read_unlock(); 1543 1544 return err; 1545 } 1546 1547 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, 1548 const struct flowi *fl) 1549 { 1550 const struct xfrm_policy_afinfo *afinfo = 1551 xfrm_policy_get_afinfo(xdst->u.dst.ops->family); 1552 int err; 1553 1554 if (!afinfo) 1555 return -EINVAL; 1556 1557 err = afinfo->fill_dst(xdst, dev, fl); 1558 1559 rcu_read_unlock(); 1560 1561 return err; 1562 } 1563 1564 1565 /* Allocate chain of dst_entry's, attach known xfrm's, calculate 1566 * all the metrics... Shortly, bundle a bundle. 1567 */ 1568 1569 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, 1570 struct xfrm_state **xfrm, 1571 struct xfrm_dst **bundle, 1572 int nx, 1573 const struct flowi *fl, 1574 struct dst_entry *dst) 1575 { 1576 struct net *net = xp_net(policy); 1577 unsigned long now = jiffies; 1578 struct net_device *dev; 1579 struct xfrm_mode *inner_mode; 1580 struct xfrm_dst *xdst_prev = NULL; 1581 struct xfrm_dst *xdst0 = NULL; 1582 int i = 0; 1583 int err; 1584 int header_len = 0; 1585 int nfheader_len = 0; 1586 int trailer_len = 0; 1587 int tos; 1588 int family = policy->selector.family; 1589 xfrm_address_t saddr, daddr; 1590 1591 xfrm_flowi_addr_get(fl, &saddr, &daddr, family); 1592 1593 tos = xfrm_get_tos(fl, family); 1594 1595 dst_hold(dst); 1596 1597 for (; i < nx; i++) { 1598 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family); 1599 struct dst_entry *dst1 = &xdst->u.dst; 1600 1601 err = PTR_ERR(xdst); 1602 if (IS_ERR(xdst)) { 1603 dst_release(dst); 1604 goto put_states; 1605 } 1606 1607 bundle[i] = xdst; 1608 if (!xdst_prev) 1609 xdst0 = xdst; 1610 else 1611 /* Ref count is taken during xfrm_alloc_dst() 1612 * No need to do dst_clone() on dst1 1613 */ 1614 xfrm_dst_set_child(xdst_prev, &xdst->u.dst); 1615 1616 if (xfrm[i]->sel.family == AF_UNSPEC) { 1617 inner_mode = xfrm_ip2inner_mode(xfrm[i], 1618 xfrm_af2proto(family)); 1619 if (!inner_mode) { 1620 err = -EAFNOSUPPORT; 1621 dst_release(dst); 1622 goto put_states; 1623 } 1624 } else 1625 inner_mode = xfrm[i]->inner_mode; 1626 1627 xdst->route = dst; 1628 dst_copy_metrics(dst1, dst); 1629 1630 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { 1631 __u32 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); 1632 1633 family = xfrm[i]->props.family; 1634 dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif, 1635 &saddr, &daddr, family, mark); 1636 err = PTR_ERR(dst); 1637 if (IS_ERR(dst)) 1638 goto put_states; 1639 } else 1640 dst_hold(dst); 1641 1642 dst1->xfrm = xfrm[i]; 1643 xdst->xfrm_genid = xfrm[i]->genid; 1644 1645 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1646 dst1->flags |= DST_HOST; 1647 dst1->lastuse = now; 1648 1649 dst1->input = dst_discard; 1650 dst1->output = inner_mode->afinfo->output; 1651 1652 xdst_prev = xdst; 1653 1654 header_len += xfrm[i]->props.header_len; 1655 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) 1656 nfheader_len += xfrm[i]->props.header_len; 1657 trailer_len += xfrm[i]->props.trailer_len; 1658 } 1659 1660 xfrm_dst_set_child(xdst_prev, dst); 1661 xdst0->path = dst; 1662 1663 err = -ENODEV; 1664 dev = dst->dev; 1665 if (!dev) 1666 goto free_dst; 1667 1668 xfrm_init_path(xdst0, dst, nfheader_len); 1669 xfrm_init_pmtu(bundle, nx); 1670 1671 for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; 1672 xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { 1673 err = xfrm_fill_dst(xdst_prev, dev, fl); 1674 if (err) 1675 goto free_dst; 1676 1677 xdst_prev->u.dst.header_len = header_len; 1678 xdst_prev->u.dst.trailer_len = trailer_len; 1679 header_len -= xdst_prev->u.dst.xfrm->props.header_len; 1680 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; 1681 } 1682 1683 return &xdst0->u.dst; 1684 1685 put_states: 1686 for (; i < nx; i++) 1687 xfrm_state_put(xfrm[i]); 1688 free_dst: 1689 if (xdst0) 1690 dst_release_immediate(&xdst0->u.dst); 1691 1692 return ERR_PTR(err); 1693 } 1694 1695 static int xfrm_expand_policies(const struct flowi *fl, u16 family, 1696 struct xfrm_policy **pols, 1697 int *num_pols, int *num_xfrms) 1698 { 1699 int i; 1700 1701 if (*num_pols == 0 || !pols[0]) { 1702 *num_pols = 0; 1703 *num_xfrms = 0; 1704 return 0; 1705 } 1706 if (IS_ERR(pols[0])) 1707 return PTR_ERR(pols[0]); 1708 1709 *num_xfrms = pols[0]->xfrm_nr; 1710 1711 #ifdef CONFIG_XFRM_SUB_POLICY 1712 if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW && 1713 pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 1714 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), 1715 XFRM_POLICY_TYPE_MAIN, 1716 fl, family, 1717 XFRM_POLICY_OUT, 1718 pols[0]->if_id); 1719 if (pols[1]) { 1720 if (IS_ERR(pols[1])) { 1721 xfrm_pols_put(pols, *num_pols); 1722 return PTR_ERR(pols[1]); 1723 } 1724 (*num_pols)++; 1725 (*num_xfrms) += pols[1]->xfrm_nr; 1726 } 1727 } 1728 #endif 1729 for (i = 0; i < *num_pols; i++) { 1730 if (pols[i]->action != XFRM_POLICY_ALLOW) { 1731 *num_xfrms = -1; 1732 break; 1733 } 1734 } 1735 1736 return 0; 1737 1738 } 1739 1740 static struct xfrm_dst * 1741 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, 1742 const struct flowi *fl, u16 family, 1743 struct dst_entry *dst_orig) 1744 { 1745 struct net *net = xp_net(pols[0]); 1746 struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; 1747 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 1748 struct xfrm_dst *xdst; 1749 struct dst_entry *dst; 1750 int err; 1751 1752 /* Try to instantiate a bundle */ 1753 err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); 1754 if (err <= 0) { 1755 if (err == 0) 1756 return NULL; 1757 1758 if (err != -EAGAIN) 1759 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 1760 return ERR_PTR(err); 1761 } 1762 1763 dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); 1764 if (IS_ERR(dst)) { 1765 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); 1766 return ERR_CAST(dst); 1767 } 1768 1769 xdst = (struct xfrm_dst *)dst; 1770 xdst->num_xfrms = err; 1771 xdst->num_pols = num_pols; 1772 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 1773 xdst->policy_genid = atomic_read(&pols[0]->genid); 1774 1775 return xdst; 1776 } 1777 1778 static void xfrm_policy_queue_process(struct timer_list *t) 1779 { 1780 struct sk_buff *skb; 1781 struct sock *sk; 1782 struct dst_entry *dst; 1783 struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); 1784 struct net *net = xp_net(pol); 1785 struct xfrm_policy_queue *pq = &pol->polq; 1786 struct flowi fl; 1787 struct sk_buff_head list; 1788 1789 spin_lock(&pq->hold_queue.lock); 1790 skb = skb_peek(&pq->hold_queue); 1791 if (!skb) { 1792 spin_unlock(&pq->hold_queue.lock); 1793 goto out; 1794 } 1795 dst = skb_dst(skb); 1796 sk = skb->sk; 1797 xfrm_decode_session(skb, &fl, dst->ops->family); 1798 spin_unlock(&pq->hold_queue.lock); 1799 1800 dst_hold(xfrm_dst_path(dst)); 1801 dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); 1802 if (IS_ERR(dst)) 1803 goto purge_queue; 1804 1805 if (dst->flags & DST_XFRM_QUEUE) { 1806 dst_release(dst); 1807 1808 if (pq->timeout >= XFRM_QUEUE_TMO_MAX) 1809 goto purge_queue; 1810 1811 pq->timeout = pq->timeout << 1; 1812 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) 1813 xfrm_pol_hold(pol); 1814 goto out; 1815 } 1816 1817 dst_release(dst); 1818 1819 __skb_queue_head_init(&list); 1820 1821 spin_lock(&pq->hold_queue.lock); 1822 pq->timeout = 0; 1823 skb_queue_splice_init(&pq->hold_queue, &list); 1824 spin_unlock(&pq->hold_queue.lock); 1825 1826 while (!skb_queue_empty(&list)) { 1827 skb = __skb_dequeue(&list); 1828 1829 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family); 1830 dst_hold(xfrm_dst_path(skb_dst(skb))); 1831 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); 1832 if (IS_ERR(dst)) { 1833 kfree_skb(skb); 1834 continue; 1835 } 1836 1837 nf_reset(skb); 1838 skb_dst_drop(skb); 1839 skb_dst_set(skb, dst); 1840 1841 dst_output(net, skb->sk, skb); 1842 } 1843 1844 out: 1845 xfrm_pol_put(pol); 1846 return; 1847 1848 purge_queue: 1849 pq->timeout = 0; 1850 skb_queue_purge(&pq->hold_queue); 1851 xfrm_pol_put(pol); 1852 } 1853 1854 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) 1855 { 1856 unsigned long sched_next; 1857 struct dst_entry *dst = skb_dst(skb); 1858 struct xfrm_dst *xdst = (struct xfrm_dst *) dst; 1859 struct xfrm_policy *pol = xdst->pols[0]; 1860 struct xfrm_policy_queue *pq = &pol->polq; 1861 1862 if (unlikely(skb_fclone_busy(sk, skb))) { 1863 kfree_skb(skb); 1864 return 0; 1865 } 1866 1867 if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { 1868 kfree_skb(skb); 1869 return -EAGAIN; 1870 } 1871 1872 skb_dst_force(skb); 1873 1874 spin_lock_bh(&pq->hold_queue.lock); 1875 1876 if (!pq->timeout) 1877 pq->timeout = XFRM_QUEUE_TMO_MIN; 1878 1879 sched_next = jiffies + pq->timeout; 1880 1881 if (del_timer(&pq->hold_timer)) { 1882 if (time_before(pq->hold_timer.expires, sched_next)) 1883 sched_next = pq->hold_timer.expires; 1884 xfrm_pol_put(pol); 1885 } 1886 1887 __skb_queue_tail(&pq->hold_queue, skb); 1888 if (!mod_timer(&pq->hold_timer, sched_next)) 1889 xfrm_pol_hold(pol); 1890 1891 spin_unlock_bh(&pq->hold_queue.lock); 1892 1893 return 0; 1894 } 1895 1896 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, 1897 struct xfrm_flo *xflo, 1898 const struct flowi *fl, 1899 int num_xfrms, 1900 u16 family) 1901 { 1902 int err; 1903 struct net_device *dev; 1904 struct dst_entry *dst; 1905 struct dst_entry *dst1; 1906 struct xfrm_dst *xdst; 1907 1908 xdst = xfrm_alloc_dst(net, family); 1909 if (IS_ERR(xdst)) 1910 return xdst; 1911 1912 if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || 1913 net->xfrm.sysctl_larval_drop || 1914 num_xfrms <= 0) 1915 return xdst; 1916 1917 dst = xflo->dst_orig; 1918 dst1 = &xdst->u.dst; 1919 dst_hold(dst); 1920 xdst->route = dst; 1921 1922 dst_copy_metrics(dst1, dst); 1923 1924 dst1->obsolete = DST_OBSOLETE_FORCE_CHK; 1925 dst1->flags |= DST_HOST | DST_XFRM_QUEUE; 1926 dst1->lastuse = jiffies; 1927 1928 dst1->input = dst_discard; 1929 dst1->output = xdst_queue_output; 1930 1931 dst_hold(dst); 1932 xfrm_dst_set_child(xdst, dst); 1933 xdst->path = dst; 1934 1935 xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); 1936 1937 err = -ENODEV; 1938 dev = dst->dev; 1939 if (!dev) 1940 goto free_dst; 1941 1942 err = xfrm_fill_dst(xdst, dev, fl); 1943 if (err) 1944 goto free_dst; 1945 1946 out: 1947 return xdst; 1948 1949 free_dst: 1950 dst_release(dst1); 1951 xdst = ERR_PTR(err); 1952 goto out; 1953 } 1954 1955 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, 1956 const struct flowi *fl, 1957 u16 family, u8 dir, 1958 struct xfrm_flo *xflo, u32 if_id) 1959 { 1960 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 1961 int num_pols = 0, num_xfrms = 0, err; 1962 struct xfrm_dst *xdst; 1963 1964 /* Resolve policies to use if we couldn't get them from 1965 * previous cache entry */ 1966 num_pols = 1; 1967 pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); 1968 err = xfrm_expand_policies(fl, family, pols, 1969 &num_pols, &num_xfrms); 1970 if (err < 0) 1971 goto inc_error; 1972 if (num_pols == 0) 1973 return NULL; 1974 if (num_xfrms <= 0) 1975 goto make_dummy_bundle; 1976 1977 xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, 1978 xflo->dst_orig); 1979 if (IS_ERR(xdst)) { 1980 err = PTR_ERR(xdst); 1981 if (err == -EREMOTE) { 1982 xfrm_pols_put(pols, num_pols); 1983 return NULL; 1984 } 1985 1986 if (err != -EAGAIN) 1987 goto error; 1988 goto make_dummy_bundle; 1989 } else if (xdst == NULL) { 1990 num_xfrms = 0; 1991 goto make_dummy_bundle; 1992 } 1993 1994 return xdst; 1995 1996 make_dummy_bundle: 1997 /* We found policies, but there's no bundles to instantiate: 1998 * either because the policy blocks, has no transformations or 1999 * we could not build template (no xfrm_states).*/ 2000 xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); 2001 if (IS_ERR(xdst)) { 2002 xfrm_pols_put(pols, num_pols); 2003 return ERR_CAST(xdst); 2004 } 2005 xdst->num_pols = num_pols; 2006 xdst->num_xfrms = num_xfrms; 2007 memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); 2008 2009 return xdst; 2010 2011 inc_error: 2012 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); 2013 error: 2014 xfrm_pols_put(pols, num_pols); 2015 return ERR_PTR(err); 2016 } 2017 2018 static struct dst_entry *make_blackhole(struct net *net, u16 family, 2019 struct dst_entry *dst_orig) 2020 { 2021 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2022 struct dst_entry *ret; 2023 2024 if (!afinfo) { 2025 dst_release(dst_orig); 2026 return ERR_PTR(-EINVAL); 2027 } else { 2028 ret = afinfo->blackhole_route(net, dst_orig); 2029 } 2030 rcu_read_unlock(); 2031 2032 return ret; 2033 } 2034 2035 /* Finds/creates a bundle for given flow and if_id 2036 * 2037 * At the moment we eat a raw IP route. Mostly to speed up lookups 2038 * on interfaces with disabled IPsec. 2039 * 2040 * xfrm_lookup uses an if_id of 0 by default, and is provided for 2041 * compatibility 2042 */ 2043 struct dst_entry *xfrm_lookup_with_ifid(struct net *net, 2044 struct dst_entry *dst_orig, 2045 const struct flowi *fl, 2046 const struct sock *sk, 2047 int flags, u32 if_id) 2048 { 2049 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2050 struct xfrm_dst *xdst; 2051 struct dst_entry *dst, *route; 2052 u16 family = dst_orig->ops->family; 2053 u8 dir = XFRM_POLICY_OUT; 2054 int i, err, num_pols, num_xfrms = 0, drop_pols = 0; 2055 2056 dst = NULL; 2057 xdst = NULL; 2058 route = NULL; 2059 2060 sk = sk_const_to_full_sk(sk); 2061 if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { 2062 num_pols = 1; 2063 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, 2064 if_id); 2065 err = xfrm_expand_policies(fl, family, pols, 2066 &num_pols, &num_xfrms); 2067 if (err < 0) 2068 goto dropdst; 2069 2070 if (num_pols) { 2071 if (num_xfrms <= 0) { 2072 drop_pols = num_pols; 2073 goto no_transform; 2074 } 2075 2076 xdst = xfrm_resolve_and_create_bundle( 2077 pols, num_pols, fl, 2078 family, dst_orig); 2079 2080 if (IS_ERR(xdst)) { 2081 xfrm_pols_put(pols, num_pols); 2082 err = PTR_ERR(xdst); 2083 if (err == -EREMOTE) 2084 goto nopol; 2085 2086 goto dropdst; 2087 } else if (xdst == NULL) { 2088 num_xfrms = 0; 2089 drop_pols = num_pols; 2090 goto no_transform; 2091 } 2092 2093 route = xdst->route; 2094 } 2095 } 2096 2097 if (xdst == NULL) { 2098 struct xfrm_flo xflo; 2099 2100 xflo.dst_orig = dst_orig; 2101 xflo.flags = flags; 2102 2103 /* To accelerate a bit... */ 2104 if ((dst_orig->flags & DST_NOXFRM) || 2105 !net->xfrm.policy_count[XFRM_POLICY_OUT]) 2106 goto nopol; 2107 2108 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); 2109 if (xdst == NULL) 2110 goto nopol; 2111 if (IS_ERR(xdst)) { 2112 err = PTR_ERR(xdst); 2113 goto dropdst; 2114 } 2115 2116 num_pols = xdst->num_pols; 2117 num_xfrms = xdst->num_xfrms; 2118 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); 2119 route = xdst->route; 2120 } 2121 2122 dst = &xdst->u.dst; 2123 if (route == NULL && num_xfrms > 0) { 2124 /* The only case when xfrm_bundle_lookup() returns a 2125 * bundle with null route, is when the template could 2126 * not be resolved. It means policies are there, but 2127 * bundle could not be created, since we don't yet 2128 * have the xfrm_state's. We need to wait for KM to 2129 * negotiate new SA's or bail out with error.*/ 2130 if (net->xfrm.sysctl_larval_drop) { 2131 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2132 err = -EREMOTE; 2133 goto error; 2134 } 2135 2136 err = -EAGAIN; 2137 2138 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); 2139 goto error; 2140 } 2141 2142 no_transform: 2143 if (num_pols == 0) 2144 goto nopol; 2145 2146 if ((flags & XFRM_LOOKUP_ICMP) && 2147 !(pols[0]->flags & XFRM_POLICY_ICMP)) { 2148 err = -ENOENT; 2149 goto error; 2150 } 2151 2152 for (i = 0; i < num_pols; i++) 2153 pols[i]->curlft.use_time = ktime_get_real_seconds(); 2154 2155 if (num_xfrms < 0) { 2156 /* Prohibit the flow */ 2157 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); 2158 err = -EPERM; 2159 goto error; 2160 } else if (num_xfrms > 0) { 2161 /* Flow transformed */ 2162 dst_release(dst_orig); 2163 } else { 2164 /* Flow passes untransformed */ 2165 dst_release(dst); 2166 dst = dst_orig; 2167 } 2168 ok: 2169 xfrm_pols_put(pols, drop_pols); 2170 if (dst && dst->xfrm && 2171 dst->xfrm->props.mode == XFRM_MODE_TUNNEL) 2172 dst->flags |= DST_XFRM_TUNNEL; 2173 return dst; 2174 2175 nopol: 2176 if (!(flags & XFRM_LOOKUP_ICMP)) { 2177 dst = dst_orig; 2178 goto ok; 2179 } 2180 err = -ENOENT; 2181 error: 2182 dst_release(dst); 2183 dropdst: 2184 if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) 2185 dst_release(dst_orig); 2186 xfrm_pols_put(pols, drop_pols); 2187 return ERR_PTR(err); 2188 } 2189 EXPORT_SYMBOL(xfrm_lookup_with_ifid); 2190 2191 /* Main function: finds/creates a bundle for given flow. 2192 * 2193 * At the moment we eat a raw IP route. Mostly to speed up lookups 2194 * on interfaces with disabled IPsec. 2195 */ 2196 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, 2197 const struct flowi *fl, const struct sock *sk, 2198 int flags) 2199 { 2200 return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); 2201 } 2202 EXPORT_SYMBOL(xfrm_lookup); 2203 2204 /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). 2205 * Otherwise we may send out blackholed packets. 2206 */ 2207 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, 2208 const struct flowi *fl, 2209 const struct sock *sk, int flags) 2210 { 2211 struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, 2212 flags | XFRM_LOOKUP_QUEUE | 2213 XFRM_LOOKUP_KEEP_DST_REF); 2214 2215 if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE) 2216 return make_blackhole(net, dst_orig->ops->family, dst_orig); 2217 2218 if (IS_ERR(dst)) 2219 dst_release(dst_orig); 2220 2221 return dst; 2222 } 2223 EXPORT_SYMBOL(xfrm_lookup_route); 2224 2225 static inline int 2226 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) 2227 { 2228 struct xfrm_state *x; 2229 2230 if (!skb->sp || idx < 0 || idx >= skb->sp->len) 2231 return 0; 2232 x = skb->sp->xvec[idx]; 2233 if (!x->type->reject) 2234 return 0; 2235 return x->type->reject(x, skb, fl); 2236 } 2237 2238 /* When skb is transformed back to its "native" form, we have to 2239 * check policy restrictions. At the moment we make this in maximally 2240 * stupid way. Shame on me. :-) Of course, connected sockets must 2241 * have policy cached at them. 2242 */ 2243 2244 static inline int 2245 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, 2246 unsigned short family) 2247 { 2248 if (xfrm_state_kern(x)) 2249 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); 2250 return x->id.proto == tmpl->id.proto && 2251 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && 2252 (x->props.reqid == tmpl->reqid || !tmpl->reqid) && 2253 x->props.mode == tmpl->mode && 2254 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) || 2255 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && 2256 !(x->props.mode != XFRM_MODE_TRANSPORT && 2257 xfrm_state_addr_cmp(tmpl, x, family)); 2258 } 2259 2260 /* 2261 * 0 or more than 0 is returned when validation is succeeded (either bypass 2262 * because of optional transport mode, or next index of the mathced secpath 2263 * state with the template. 2264 * -1 is returned when no matching template is found. 2265 * Otherwise "-2 - errored_index" is returned. 2266 */ 2267 static inline int 2268 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, 2269 unsigned short family) 2270 { 2271 int idx = start; 2272 2273 if (tmpl->optional) { 2274 if (tmpl->mode == XFRM_MODE_TRANSPORT) 2275 return start; 2276 } else 2277 start = -1; 2278 for (; idx < sp->len; idx++) { 2279 if (xfrm_state_ok(tmpl, sp->xvec[idx], family)) 2280 return ++idx; 2281 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { 2282 if (start == -1) 2283 start = -2-idx; 2284 break; 2285 } 2286 } 2287 return start; 2288 } 2289 2290 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, 2291 unsigned int family, int reverse) 2292 { 2293 const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); 2294 int err; 2295 2296 if (unlikely(afinfo == NULL)) 2297 return -EAFNOSUPPORT; 2298 2299 afinfo->decode_session(skb, fl, reverse); 2300 2301 err = security_xfrm_decode_session(skb, &fl->flowi_secid); 2302 rcu_read_unlock(); 2303 return err; 2304 } 2305 EXPORT_SYMBOL(__xfrm_decode_session); 2306 2307 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) 2308 { 2309 for (; k < sp->len; k++) { 2310 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { 2311 *idxp = k; 2312 return 1; 2313 } 2314 } 2315 2316 return 0; 2317 } 2318 2319 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, 2320 unsigned short family) 2321 { 2322 struct net *net = dev_net(skb->dev); 2323 struct xfrm_policy *pol; 2324 struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; 2325 int npols = 0; 2326 int xfrm_nr; 2327 int pi; 2328 int reverse; 2329 struct flowi fl; 2330 int xerr_idx = -1; 2331 const struct xfrm_if_cb *ifcb; 2332 struct xfrm_if *xi; 2333 u32 if_id = 0; 2334 2335 rcu_read_lock(); 2336 ifcb = xfrm_if_get_cb(); 2337 2338 if (ifcb) { 2339 xi = ifcb->decode_session(skb); 2340 if (xi) 2341 if_id = xi->p.if_id; 2342 } 2343 rcu_read_unlock(); 2344 2345 reverse = dir & ~XFRM_POLICY_MASK; 2346 dir &= XFRM_POLICY_MASK; 2347 2348 if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) { 2349 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); 2350 return 0; 2351 } 2352 2353 nf_nat_decode_session(skb, &fl, family); 2354 2355 /* First, check used SA against their selectors. */ 2356 if (skb->sp) { 2357 int i; 2358 2359 for (i = skb->sp->len-1; i >= 0; i--) { 2360 struct xfrm_state *x = skb->sp->xvec[i]; 2361 if (!xfrm_selector_match(&x->sel, &fl, family)) { 2362 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); 2363 return 0; 2364 } 2365 } 2366 } 2367 2368 pol = NULL; 2369 sk = sk_to_full_sk(sk); 2370 if (sk && sk->sk_policy[dir]) { 2371 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id); 2372 if (IS_ERR(pol)) { 2373 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2374 return 0; 2375 } 2376 } 2377 2378 if (!pol) 2379 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id); 2380 2381 if (IS_ERR(pol)) { 2382 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2383 return 0; 2384 } 2385 2386 if (!pol) { 2387 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) { 2388 xfrm_secpath_reject(xerr_idx, skb, &fl); 2389 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS); 2390 return 0; 2391 } 2392 return 1; 2393 } 2394 2395 pol->curlft.use_time = ktime_get_real_seconds(); 2396 2397 pols[0] = pol; 2398 npols++; 2399 #ifdef CONFIG_XFRM_SUB_POLICY 2400 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) { 2401 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, 2402 &fl, family, 2403 XFRM_POLICY_IN, if_id); 2404 if (pols[1]) { 2405 if (IS_ERR(pols[1])) { 2406 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR); 2407 return 0; 2408 } 2409 pols[1]->curlft.use_time = ktime_get_real_seconds(); 2410 npols++; 2411 } 2412 } 2413 #endif 2414 2415 if (pol->action == XFRM_POLICY_ALLOW) { 2416 struct sec_path *sp; 2417 static struct sec_path dummy; 2418 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH]; 2419 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH]; 2420 struct xfrm_tmpl **tpp = tp; 2421 int ti = 0; 2422 int i, k; 2423 2424 if ((sp = skb->sp) == NULL) 2425 sp = &dummy; 2426 2427 for (pi = 0; pi < npols; pi++) { 2428 if (pols[pi] != pol && 2429 pols[pi]->action != XFRM_POLICY_ALLOW) { 2430 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2431 goto reject; 2432 } 2433 if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) { 2434 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 2435 goto reject_error; 2436 } 2437 for (i = 0; i < pols[pi]->xfrm_nr; i++) 2438 tpp[ti++] = &pols[pi]->xfrm_vec[i]; 2439 } 2440 xfrm_nr = ti; 2441 if (npols > 1) { 2442 xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net); 2443 tpp = stp; 2444 } 2445 2446 /* For each tunnel xfrm, find the first matching tmpl. 2447 * For each tmpl before that, find corresponding xfrm. 2448 * Order is _important_. Later we will implement 2449 * some barriers, but at the moment barriers 2450 * are implied between each two transformations. 2451 */ 2452 for (i = xfrm_nr-1, k = 0; i >= 0; i--) { 2453 k = xfrm_policy_ok(tpp[i], sp, k, family); 2454 if (k < 0) { 2455 if (k < -1) 2456 /* "-2 - errored_index" returned */ 2457 xerr_idx = -(2+k); 2458 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2459 goto reject; 2460 } 2461 } 2462 2463 if (secpath_has_nontransport(sp, k, &xerr_idx)) { 2464 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH); 2465 goto reject; 2466 } 2467 2468 xfrm_pols_put(pols, npols); 2469 return 1; 2470 } 2471 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK); 2472 2473 reject: 2474 xfrm_secpath_reject(xerr_idx, skb, &fl); 2475 reject_error: 2476 xfrm_pols_put(pols, npols); 2477 return 0; 2478 } 2479 EXPORT_SYMBOL(__xfrm_policy_check); 2480 2481 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) 2482 { 2483 struct net *net = dev_net(skb->dev); 2484 struct flowi fl; 2485 struct dst_entry *dst; 2486 int res = 1; 2487 2488 if (xfrm_decode_session(skb, &fl, family) < 0) { 2489 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2490 return 0; 2491 } 2492 2493 skb_dst_force(skb); 2494 if (!skb_dst(skb)) { 2495 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); 2496 return 0; 2497 } 2498 2499 dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); 2500 if (IS_ERR(dst)) { 2501 res = 0; 2502 dst = NULL; 2503 } 2504 skb_dst_set(skb, dst); 2505 return res; 2506 } 2507 EXPORT_SYMBOL(__xfrm_route_forward); 2508 2509 /* Optimize later using cookies and generation ids. */ 2510 2511 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) 2512 { 2513 /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete 2514 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to 2515 * get validated by dst_ops->check on every use. We do this 2516 * because when a normal route referenced by an XFRM dst is 2517 * obsoleted we do not go looking around for all parent 2518 * referencing XFRM dsts so that we can invalidate them. It 2519 * is just too much work. Instead we make the checks here on 2520 * every use. For example: 2521 * 2522 * XFRM dst A --> IPv4 dst X 2523 * 2524 * X is the "xdst->route" of A (X is also the "dst->path" of A 2525 * in this example). If X is marked obsolete, "A" will not 2526 * notice. That's what we are validating here via the 2527 * stale_bundle() check. 2528 * 2529 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will 2530 * be marked on it. 2531 * This will force stale_bundle() to fail on any xdst bundle with 2532 * this dst linked in it. 2533 */ 2534 if (dst->obsolete < 0 && !stale_bundle(dst)) 2535 return dst; 2536 2537 return NULL; 2538 } 2539 2540 static int stale_bundle(struct dst_entry *dst) 2541 { 2542 return !xfrm_bundle_ok((struct xfrm_dst *)dst); 2543 } 2544 2545 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) 2546 { 2547 while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) { 2548 dst->dev = dev_net(dev)->loopback_dev; 2549 dev_hold(dst->dev); 2550 dev_put(dev); 2551 } 2552 } 2553 EXPORT_SYMBOL(xfrm_dst_ifdown); 2554 2555 static void xfrm_link_failure(struct sk_buff *skb) 2556 { 2557 /* Impossible. Such dst must be popped before reaches point of failure. */ 2558 } 2559 2560 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) 2561 { 2562 if (dst) { 2563 if (dst->obsolete) { 2564 dst_release(dst); 2565 dst = NULL; 2566 } 2567 } 2568 return dst; 2569 } 2570 2571 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr) 2572 { 2573 while (nr--) { 2574 struct xfrm_dst *xdst = bundle[nr]; 2575 u32 pmtu, route_mtu_cached; 2576 struct dst_entry *dst; 2577 2578 dst = &xdst->u.dst; 2579 pmtu = dst_mtu(xfrm_dst_child(dst)); 2580 xdst->child_mtu_cached = pmtu; 2581 2582 pmtu = xfrm_state_mtu(dst->xfrm, pmtu); 2583 2584 route_mtu_cached = dst_mtu(xdst->route); 2585 xdst->route_mtu_cached = route_mtu_cached; 2586 2587 if (pmtu > route_mtu_cached) 2588 pmtu = route_mtu_cached; 2589 2590 dst_metric_set(dst, RTAX_MTU, pmtu); 2591 } 2592 } 2593 2594 /* Check that the bundle accepts the flow and its components are 2595 * still valid. 2596 */ 2597 2598 static int xfrm_bundle_ok(struct xfrm_dst *first) 2599 { 2600 struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; 2601 struct dst_entry *dst = &first->u.dst; 2602 struct xfrm_dst *xdst; 2603 int start_from, nr; 2604 u32 mtu; 2605 2606 if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) || 2607 (dst->dev && !netif_running(dst->dev))) 2608 return 0; 2609 2610 if (dst->flags & DST_XFRM_QUEUE) 2611 return 1; 2612 2613 start_from = nr = 0; 2614 do { 2615 struct xfrm_dst *xdst = (struct xfrm_dst *)dst; 2616 2617 if (dst->xfrm->km.state != XFRM_STATE_VALID) 2618 return 0; 2619 if (xdst->xfrm_genid != dst->xfrm->genid) 2620 return 0; 2621 if (xdst->num_pols > 0 && 2622 xdst->policy_genid != atomic_read(&xdst->pols[0]->genid)) 2623 return 0; 2624 2625 bundle[nr++] = xdst; 2626 2627 mtu = dst_mtu(xfrm_dst_child(dst)); 2628 if (xdst->child_mtu_cached != mtu) { 2629 start_from = nr; 2630 xdst->child_mtu_cached = mtu; 2631 } 2632 2633 if (!dst_check(xdst->route, xdst->route_cookie)) 2634 return 0; 2635 mtu = dst_mtu(xdst->route); 2636 if (xdst->route_mtu_cached != mtu) { 2637 start_from = nr; 2638 xdst->route_mtu_cached = mtu; 2639 } 2640 2641 dst = xfrm_dst_child(dst); 2642 } while (dst->xfrm); 2643 2644 if (likely(!start_from)) 2645 return 1; 2646 2647 xdst = bundle[start_from - 1]; 2648 mtu = xdst->child_mtu_cached; 2649 while (start_from--) { 2650 dst = &xdst->u.dst; 2651 2652 mtu = xfrm_state_mtu(dst->xfrm, mtu); 2653 if (mtu > xdst->route_mtu_cached) 2654 mtu = xdst->route_mtu_cached; 2655 dst_metric_set(dst, RTAX_MTU, mtu); 2656 if (!start_from) 2657 break; 2658 2659 xdst = bundle[start_from - 1]; 2660 xdst->child_mtu_cached = mtu; 2661 } 2662 2663 return 1; 2664 } 2665 2666 static unsigned int xfrm_default_advmss(const struct dst_entry *dst) 2667 { 2668 return dst_metric_advmss(xfrm_dst_path(dst)); 2669 } 2670 2671 static unsigned int xfrm_mtu(const struct dst_entry *dst) 2672 { 2673 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); 2674 2675 return mtu ? : dst_mtu(xfrm_dst_path(dst)); 2676 } 2677 2678 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst, 2679 const void *daddr) 2680 { 2681 while (dst->xfrm) { 2682 const struct xfrm_state *xfrm = dst->xfrm; 2683 2684 dst = xfrm_dst_child(dst); 2685 2686 if (xfrm->props.mode == XFRM_MODE_TRANSPORT) 2687 continue; 2688 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) 2689 daddr = xfrm->coaddr; 2690 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) 2691 daddr = &xfrm->id.daddr; 2692 } 2693 return daddr; 2694 } 2695 2696 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, 2697 struct sk_buff *skb, 2698 const void *daddr) 2699 { 2700 const struct dst_entry *path = xfrm_dst_path(dst); 2701 2702 if (!skb) 2703 daddr = xfrm_get_dst_nexthop(dst, daddr); 2704 return path->ops->neigh_lookup(path, skb, daddr); 2705 } 2706 2707 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) 2708 { 2709 const struct dst_entry *path = xfrm_dst_path(dst); 2710 2711 daddr = xfrm_get_dst_nexthop(dst, daddr); 2712 path->ops->confirm_neigh(path, daddr); 2713 } 2714 2715 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family) 2716 { 2717 int err = 0; 2718 2719 if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo))) 2720 return -EAFNOSUPPORT; 2721 2722 spin_lock(&xfrm_policy_afinfo_lock); 2723 if (unlikely(xfrm_policy_afinfo[family] != NULL)) 2724 err = -EEXIST; 2725 else { 2726 struct dst_ops *dst_ops = afinfo->dst_ops; 2727 if (likely(dst_ops->kmem_cachep == NULL)) 2728 dst_ops->kmem_cachep = xfrm_dst_cache; 2729 if (likely(dst_ops->check == NULL)) 2730 dst_ops->check = xfrm_dst_check; 2731 if (likely(dst_ops->default_advmss == NULL)) 2732 dst_ops->default_advmss = xfrm_default_advmss; 2733 if (likely(dst_ops->mtu == NULL)) 2734 dst_ops->mtu = xfrm_mtu; 2735 if (likely(dst_ops->negative_advice == NULL)) 2736 dst_ops->negative_advice = xfrm_negative_advice; 2737 if (likely(dst_ops->link_failure == NULL)) 2738 dst_ops->link_failure = xfrm_link_failure; 2739 if (likely(dst_ops->neigh_lookup == NULL)) 2740 dst_ops->neigh_lookup = xfrm_neigh_lookup; 2741 if (likely(!dst_ops->confirm_neigh)) 2742 dst_ops->confirm_neigh = xfrm_confirm_neigh; 2743 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo); 2744 } 2745 spin_unlock(&xfrm_policy_afinfo_lock); 2746 2747 return err; 2748 } 2749 EXPORT_SYMBOL(xfrm_policy_register_afinfo); 2750 2751 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo) 2752 { 2753 struct dst_ops *dst_ops = afinfo->dst_ops; 2754 int i; 2755 2756 for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) { 2757 if (xfrm_policy_afinfo[i] != afinfo) 2758 continue; 2759 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL); 2760 break; 2761 } 2762 2763 synchronize_rcu(); 2764 2765 dst_ops->kmem_cachep = NULL; 2766 dst_ops->check = NULL; 2767 dst_ops->negative_advice = NULL; 2768 dst_ops->link_failure = NULL; 2769 } 2770 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); 2771 2772 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb) 2773 { 2774 spin_lock(&xfrm_if_cb_lock); 2775 rcu_assign_pointer(xfrm_if_cb, ifcb); 2776 spin_unlock(&xfrm_if_cb_lock); 2777 } 2778 EXPORT_SYMBOL(xfrm_if_register_cb); 2779 2780 void xfrm_if_unregister_cb(void) 2781 { 2782 RCU_INIT_POINTER(xfrm_if_cb, NULL); 2783 synchronize_rcu(); 2784 } 2785 EXPORT_SYMBOL(xfrm_if_unregister_cb); 2786 2787 #ifdef CONFIG_XFRM_STATISTICS 2788 static int __net_init xfrm_statistics_init(struct net *net) 2789 { 2790 int rv; 2791 net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib); 2792 if (!net->mib.xfrm_statistics) 2793 return -ENOMEM; 2794 rv = xfrm_proc_init(net); 2795 if (rv < 0) 2796 free_percpu(net->mib.xfrm_statistics); 2797 return rv; 2798 } 2799 2800 static void xfrm_statistics_fini(struct net *net) 2801 { 2802 xfrm_proc_fini(net); 2803 free_percpu(net->mib.xfrm_statistics); 2804 } 2805 #else 2806 static int __net_init xfrm_statistics_init(struct net *net) 2807 { 2808 return 0; 2809 } 2810 2811 static void xfrm_statistics_fini(struct net *net) 2812 { 2813 } 2814 #endif 2815 2816 static int __net_init xfrm_policy_init(struct net *net) 2817 { 2818 unsigned int hmask, sz; 2819 int dir; 2820 2821 if (net_eq(net, &init_net)) 2822 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", 2823 sizeof(struct xfrm_dst), 2824 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 2825 NULL); 2826 2827 hmask = 8 - 1; 2828 sz = (hmask+1) * sizeof(struct hlist_head); 2829 2830 net->xfrm.policy_byidx = xfrm_hash_alloc(sz); 2831 if (!net->xfrm.policy_byidx) 2832 goto out_byidx; 2833 net->xfrm.policy_idx_hmask = hmask; 2834 2835 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2836 struct xfrm_policy_hash *htab; 2837 2838 net->xfrm.policy_count[dir] = 0; 2839 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0; 2840 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]); 2841 2842 htab = &net->xfrm.policy_bydst[dir]; 2843 htab->table = xfrm_hash_alloc(sz); 2844 if (!htab->table) 2845 goto out_bydst; 2846 htab->hmask = hmask; 2847 htab->dbits4 = 32; 2848 htab->sbits4 = 32; 2849 htab->dbits6 = 128; 2850 htab->sbits6 = 128; 2851 } 2852 net->xfrm.policy_hthresh.lbits4 = 32; 2853 net->xfrm.policy_hthresh.rbits4 = 32; 2854 net->xfrm.policy_hthresh.lbits6 = 128; 2855 net->xfrm.policy_hthresh.rbits6 = 128; 2856 2857 seqlock_init(&net->xfrm.policy_hthresh.lock); 2858 2859 INIT_LIST_HEAD(&net->xfrm.policy_all); 2860 INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize); 2861 INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild); 2862 return 0; 2863 2864 out_bydst: 2865 for (dir--; dir >= 0; dir--) { 2866 struct xfrm_policy_hash *htab; 2867 2868 htab = &net->xfrm.policy_bydst[dir]; 2869 xfrm_hash_free(htab->table, sz); 2870 } 2871 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2872 out_byidx: 2873 return -ENOMEM; 2874 } 2875 2876 static void xfrm_policy_fini(struct net *net) 2877 { 2878 unsigned int sz; 2879 int dir; 2880 2881 flush_work(&net->xfrm.policy_hash_work); 2882 #ifdef CONFIG_XFRM_SUB_POLICY 2883 xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false); 2884 #endif 2885 xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false); 2886 2887 WARN_ON(!list_empty(&net->xfrm.policy_all)); 2888 2889 for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { 2890 struct xfrm_policy_hash *htab; 2891 2892 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir])); 2893 2894 htab = &net->xfrm.policy_bydst[dir]; 2895 sz = (htab->hmask + 1) * sizeof(struct hlist_head); 2896 WARN_ON(!hlist_empty(htab->table)); 2897 xfrm_hash_free(htab->table, sz); 2898 } 2899 2900 sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head); 2901 WARN_ON(!hlist_empty(net->xfrm.policy_byidx)); 2902 xfrm_hash_free(net->xfrm.policy_byidx, sz); 2903 } 2904 2905 static int __net_init xfrm_net_init(struct net *net) 2906 { 2907 int rv; 2908 2909 /* Initialize the per-net locks here */ 2910 spin_lock_init(&net->xfrm.xfrm_state_lock); 2911 spin_lock_init(&net->xfrm.xfrm_policy_lock); 2912 mutex_init(&net->xfrm.xfrm_cfg_mutex); 2913 2914 rv = xfrm_statistics_init(net); 2915 if (rv < 0) 2916 goto out_statistics; 2917 rv = xfrm_state_init(net); 2918 if (rv < 0) 2919 goto out_state; 2920 rv = xfrm_policy_init(net); 2921 if (rv < 0) 2922 goto out_policy; 2923 rv = xfrm_sysctl_init(net); 2924 if (rv < 0) 2925 goto out_sysctl; 2926 2927 return 0; 2928 2929 out_sysctl: 2930 xfrm_policy_fini(net); 2931 out_policy: 2932 xfrm_state_fini(net); 2933 out_state: 2934 xfrm_statistics_fini(net); 2935 out_statistics: 2936 return rv; 2937 } 2938 2939 static void __net_exit xfrm_net_exit(struct net *net) 2940 { 2941 xfrm_sysctl_fini(net); 2942 xfrm_policy_fini(net); 2943 xfrm_state_fini(net); 2944 xfrm_statistics_fini(net); 2945 } 2946 2947 static struct pernet_operations __net_initdata xfrm_net_ops = { 2948 .init = xfrm_net_init, 2949 .exit = xfrm_net_exit, 2950 }; 2951 2952 void __init xfrm_init(void) 2953 { 2954 register_pernet_subsys(&xfrm_net_ops); 2955 xfrm_dev_init(); 2956 seqcount_init(&xfrm_policy_hash_generation); 2957 xfrm_input_init(); 2958 2959 RCU_INIT_POINTER(xfrm_if_cb, NULL); 2960 synchronize_rcu(); 2961 } 2962 2963 #ifdef CONFIG_AUDITSYSCALL 2964 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp, 2965 struct audit_buffer *audit_buf) 2966 { 2967 struct xfrm_sec_ctx *ctx = xp->security; 2968 struct xfrm_selector *sel = &xp->selector; 2969 2970 if (ctx) 2971 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s", 2972 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str); 2973 2974 switch (sel->family) { 2975 case AF_INET: 2976 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4); 2977 if (sel->prefixlen_s != 32) 2978 audit_log_format(audit_buf, " src_prefixlen=%d", 2979 sel->prefixlen_s); 2980 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4); 2981 if (sel->prefixlen_d != 32) 2982 audit_log_format(audit_buf, " dst_prefixlen=%d", 2983 sel->prefixlen_d); 2984 break; 2985 case AF_INET6: 2986 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6); 2987 if (sel->prefixlen_s != 128) 2988 audit_log_format(audit_buf, " src_prefixlen=%d", 2989 sel->prefixlen_s); 2990 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6); 2991 if (sel->prefixlen_d != 128) 2992 audit_log_format(audit_buf, " dst_prefixlen=%d", 2993 sel->prefixlen_d); 2994 break; 2995 } 2996 } 2997 2998 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid) 2999 { 3000 struct audit_buffer *audit_buf; 3001 3002 audit_buf = xfrm_audit_start("SPD-add"); 3003 if (audit_buf == NULL) 3004 return; 3005 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3006 audit_log_format(audit_buf, " res=%u", result); 3007 xfrm_audit_common_policyinfo(xp, audit_buf); 3008 audit_log_end(audit_buf); 3009 } 3010 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add); 3011 3012 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result, 3013 bool task_valid) 3014 { 3015 struct audit_buffer *audit_buf; 3016 3017 audit_buf = xfrm_audit_start("SPD-delete"); 3018 if (audit_buf == NULL) 3019 return; 3020 xfrm_audit_helper_usrinfo(task_valid, audit_buf); 3021 audit_log_format(audit_buf, " res=%u", result); 3022 xfrm_audit_common_policyinfo(xp, audit_buf); 3023 audit_log_end(audit_buf); 3024 } 3025 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete); 3026 #endif 3027 3028 #ifdef CONFIG_XFRM_MIGRATE 3029 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, 3030 const struct xfrm_selector *sel_tgt) 3031 { 3032 if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { 3033 if (sel_tgt->family == sel_cmp->family && 3034 xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, 3035 sel_cmp->family) && 3036 xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, 3037 sel_cmp->family) && 3038 sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && 3039 sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { 3040 return true; 3041 } 3042 } else { 3043 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { 3044 return true; 3045 } 3046 } 3047 return false; 3048 } 3049 3050 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel, 3051 u8 dir, u8 type, struct net *net) 3052 { 3053 struct xfrm_policy *pol, *ret = NULL; 3054 struct hlist_head *chain; 3055 u32 priority = ~0U; 3056 3057 spin_lock_bh(&net->xfrm.xfrm_policy_lock); 3058 chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); 3059 hlist_for_each_entry(pol, chain, bydst) { 3060 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3061 pol->type == type) { 3062 ret = pol; 3063 priority = ret->priority; 3064 break; 3065 } 3066 } 3067 chain = &net->xfrm.policy_inexact[dir]; 3068 hlist_for_each_entry(pol, chain, bydst) { 3069 if ((pol->priority >= priority) && ret) 3070 break; 3071 3072 if (xfrm_migrate_selector_match(sel, &pol->selector) && 3073 pol->type == type) { 3074 ret = pol; 3075 break; 3076 } 3077 } 3078 3079 xfrm_pol_hold(ret); 3080 3081 spin_unlock_bh(&net->xfrm.xfrm_policy_lock); 3082 3083 return ret; 3084 } 3085 3086 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t) 3087 { 3088 int match = 0; 3089 3090 if (t->mode == m->mode && t->id.proto == m->proto && 3091 (m->reqid == 0 || t->reqid == m->reqid)) { 3092 switch (t->mode) { 3093 case XFRM_MODE_TUNNEL: 3094 case XFRM_MODE_BEET: 3095 if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr, 3096 m->old_family) && 3097 xfrm_addr_equal(&t->saddr, &m->old_saddr, 3098 m->old_family)) { 3099 match = 1; 3100 } 3101 break; 3102 case XFRM_MODE_TRANSPORT: 3103 /* in case of transport mode, template does not store 3104 any IP addresses, hence we just compare mode and 3105 protocol */ 3106 match = 1; 3107 break; 3108 default: 3109 break; 3110 } 3111 } 3112 return match; 3113 } 3114 3115 /* update endpoint address(es) of template(s) */ 3116 static int xfrm_policy_migrate(struct xfrm_policy *pol, 3117 struct xfrm_migrate *m, int num_migrate) 3118 { 3119 struct xfrm_migrate *mp; 3120 int i, j, n = 0; 3121 3122 write_lock_bh(&pol->lock); 3123 if (unlikely(pol->walk.dead)) { 3124 /* target policy has been deleted */ 3125 write_unlock_bh(&pol->lock); 3126 return -ENOENT; 3127 } 3128 3129 for (i = 0; i < pol->xfrm_nr; i++) { 3130 for (j = 0, mp = m; j < num_migrate; j++, mp++) { 3131 if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) 3132 continue; 3133 n++; 3134 if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && 3135 pol->xfrm_vec[i].mode != XFRM_MODE_BEET) 3136 continue; 3137 /* update endpoints */ 3138 memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, 3139 sizeof(pol->xfrm_vec[i].id.daddr)); 3140 memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, 3141 sizeof(pol->xfrm_vec[i].saddr)); 3142 pol->xfrm_vec[i].encap_family = mp->new_family; 3143 /* flush bundles */ 3144 atomic_inc(&pol->genid); 3145 } 3146 } 3147 3148 write_unlock_bh(&pol->lock); 3149 3150 if (!n) 3151 return -ENODATA; 3152 3153 return 0; 3154 } 3155 3156 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate) 3157 { 3158 int i, j; 3159 3160 if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) 3161 return -EINVAL; 3162 3163 for (i = 0; i < num_migrate; i++) { 3164 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || 3165 xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) 3166 return -EINVAL; 3167 3168 /* check if there is any duplicated entry */ 3169 for (j = i + 1; j < num_migrate; j++) { 3170 if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, 3171 sizeof(m[i].old_daddr)) && 3172 !memcmp(&m[i].old_saddr, &m[j].old_saddr, 3173 sizeof(m[i].old_saddr)) && 3174 m[i].proto == m[j].proto && 3175 m[i].mode == m[j].mode && 3176 m[i].reqid == m[j].reqid && 3177 m[i].old_family == m[j].old_family) 3178 return -EINVAL; 3179 } 3180 } 3181 3182 return 0; 3183 } 3184 3185 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, 3186 struct xfrm_migrate *m, int num_migrate, 3187 struct xfrm_kmaddress *k, struct net *net, 3188 struct xfrm_encap_tmpl *encap) 3189 { 3190 int i, err, nx_cur = 0, nx_new = 0; 3191 struct xfrm_policy *pol = NULL; 3192 struct xfrm_state *x, *xc; 3193 struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; 3194 struct xfrm_state *x_new[XFRM_MAX_DEPTH]; 3195 struct xfrm_migrate *mp; 3196 3197 /* Stage 0 - sanity checks */ 3198 if ((err = xfrm_migrate_check(m, num_migrate)) < 0) 3199 goto out; 3200 3201 if (dir >= XFRM_POLICY_MAX) { 3202 err = -EINVAL; 3203 goto out; 3204 } 3205 3206 /* Stage 1 - find policy */ 3207 if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) { 3208 err = -ENOENT; 3209 goto out; 3210 } 3211 3212 /* Stage 2 - find and update state(s) */ 3213 for (i = 0, mp = m; i < num_migrate; i++, mp++) { 3214 if ((x = xfrm_migrate_state_find(mp, net))) { 3215 x_cur[nx_cur] = x; 3216 nx_cur++; 3217 xc = xfrm_state_migrate(x, mp, encap); 3218 if (xc) { 3219 x_new[nx_new] = xc; 3220 nx_new++; 3221 } else { 3222 err = -ENODATA; 3223 goto restore_state; 3224 } 3225 } 3226 } 3227 3228 /* Stage 3 - update policy */ 3229 if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0) 3230 goto restore_state; 3231 3232 /* Stage 4 - delete old state(s) */ 3233 if (nx_cur) { 3234 xfrm_states_put(x_cur, nx_cur); 3235 xfrm_states_delete(x_cur, nx_cur); 3236 } 3237 3238 /* Stage 5 - announce */ 3239 km_migrate(sel, dir, type, m, num_migrate, k, encap); 3240 3241 xfrm_pol_put(pol); 3242 3243 return 0; 3244 out: 3245 return err; 3246 3247 restore_state: 3248 if (pol) 3249 xfrm_pol_put(pol); 3250 if (nx_cur) 3251 xfrm_states_put(x_cur, nx_cur); 3252 if (nx_new) 3253 xfrm_states_delete(x_new, nx_new); 3254 3255 return err; 3256 } 3257 EXPORT_SYMBOL(xfrm_migrate); 3258 #endif 3259