net/xfrm/xfrm_policy.c

   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/config.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 <net/xfrm.h>
  27 #include <net/ip.h>
  28
  29 DECLARE_MUTEX(xfrm_cfg_sem);
  30 EXPORT_SYMBOL(xfrm_cfg_sem);
  31
  32 static DEFINE_RWLOCK(xfrm_policy_lock);
  33
  34 struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2];
  35 EXPORT_SYMBOL(xfrm_policy_list);
  36
  37 static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
  38 static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
  39
  40 static kmem_cache_t *xfrm_dst_cache __read_mostly;
  41
  42 static struct work_struct xfrm_policy_gc_work;
  43 static struct list_head xfrm_policy_gc_list =
  44         LIST_HEAD_INIT(xfrm_policy_gc_list);
  45 static DEFINE_SPINLOCK(xfrm_policy_gc_lock);
  46
  47 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
  48 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
  49
  50 int xfrm_register_type(struct xfrm_type *type, unsigned short family)
  51 {
  52         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
  53         struct xfrm_type_map *typemap;
  54         int err = 0;
  55
  56         if (unlikely(afinfo == NULL))
  57                 return -EAFNOSUPPORT;
  58         typemap = afinfo->type_map;
  59
  60         write_lock(&typemap->lock);
  61         if (likely(typemap->map[type->proto] == NULL))
  62                 typemap->map[type->proto] = type;
  63         else
  64                 err = -EEXIST;
  65         write_unlock(&typemap->lock);
  66         xfrm_policy_put_afinfo(afinfo);
  67         return err;
  68 }
  69 EXPORT_SYMBOL(xfrm_register_type);
  70
  71 int xfrm_unregister_type(struct xfrm_type *type, unsigned short family)
  72 {
  73         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
  74         struct xfrm_type_map *typemap;
  75         int err = 0;
  76
  77         if (unlikely(afinfo == NULL))
  78                 return -EAFNOSUPPORT;
  79         typemap = afinfo->type_map;
  80
  81         write_lock(&typemap->lock);
  82         if (unlikely(typemap->map[type->proto] != type))
  83                 err = -ENOENT;
  84         else
  85                 typemap->map[type->proto] = NULL;
  86         write_unlock(&typemap->lock);
  87         xfrm_policy_put_afinfo(afinfo);
  88         return err;
  89 }
  90 EXPORT_SYMBOL(xfrm_unregister_type);
  91
  92 struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family)
  93 {
  94         struct xfrm_policy_afinfo *afinfo;
  95         struct xfrm_type_map *typemap;
  96         struct xfrm_type *type;
  97         int modload_attempted = 0;
  98
  99 retry:
 100         afinfo = xfrm_policy_get_afinfo(family);
 101         if (unlikely(afinfo == NULL))
 102                 return NULL;
 103         typemap = afinfo->type_map;
 104
 105         read_lock(&typemap->lock);
 106         type = typemap->map[proto];
 107         if (unlikely(type && !try_module_get(type->owner)))
 108                 type = NULL;
 109         read_unlock(&typemap->lock);
 110         if (!type && !modload_attempted) {
 111                 xfrm_policy_put_afinfo(afinfo);
 112                 request_module("xfrm-type-%d-%d",
 113                                (int) family, (int) proto);
 114                 modload_attempted = 1;
 115                 goto retry;
 116         }
 117
 118         xfrm_policy_put_afinfo(afinfo);
 119         return type;
 120 }
 121
 122 int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl,
 123                     unsigned short family)
 124 {
 125         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 126         int err = 0;
 127
 128         if (unlikely(afinfo == NULL))
 129                 return -EAFNOSUPPORT;
 130
 131         if (likely(afinfo->dst_lookup != NULL))
 132                 err = afinfo->dst_lookup(dst, fl);
 133         else
 134                 err = -EINVAL;
 135         xfrm_policy_put_afinfo(afinfo);
 136         return err;
 137 }
 138 EXPORT_SYMBOL(xfrm_dst_lookup);
 139
 140 void xfrm_put_type(struct xfrm_type *type)
 141 {
 142         module_put(type->owner);
 143 }
 144
 145 static inline unsigned long make_jiffies(long secs)
 146 {
 147         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 148                 return MAX_SCHEDULE_TIMEOUT-1;
 149         else
 150                 return secs*HZ;
 151 }
 152
 153 static void xfrm_policy_timer(unsigned long data)
 154 {
 155         struct xfrm_policy *xp = (struct xfrm_policy*)data;
 156         unsigned long now = (unsigned long)xtime.tv_sec;
 157         long next = LONG_MAX;
 158         int warn = 0;
 159         int dir;
 160
 161         read_lock(&xp->lock);
 162
 163         if (xp->dead)
 164                 goto out;
 165
 166         dir = xfrm_policy_id2dir(xp->index);
 167
 168         if (xp->lft.hard_add_expires_seconds) {
 169                 long tmo = xp->lft.hard_add_expires_seconds +
 170                         xp->curlft.add_time - now;
 171                 if (tmo <= 0)
 172                         goto expired;
 173                 if (tmo < next)
 174                         next = tmo;
 175         }
 176         if (xp->lft.hard_use_expires_seconds) {
 177                 long tmo = xp->lft.hard_use_expires_seconds +
 178                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 179                 if (tmo <= 0)
 180                         goto expired;
 181                 if (tmo < next)
 182                         next = tmo;
 183         }
 184         if (xp->lft.soft_add_expires_seconds) {
 185                 long tmo = xp->lft.soft_add_expires_seconds +
 186                         xp->curlft.add_time - now;
 187                 if (tmo <= 0) {
 188                         warn = 1;
 189                         tmo = XFRM_KM_TIMEOUT;
 190                 }
 191                 if (tmo < next)
 192                         next = tmo;
 193         }
 194         if (xp->lft.soft_use_expires_seconds) {
 195                 long tmo = xp->lft.soft_use_expires_seconds +
 196                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 197                 if (tmo <= 0) {
 198                         warn = 1;
 199                         tmo = XFRM_KM_TIMEOUT;
 200                 }
 201                 if (tmo < next)
 202                         next = tmo;
 203         }
 204
 205         if (warn)
 206                 km_policy_expired(xp, dir, 0);
 207         if (next != LONG_MAX &&
 208             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 209                 xfrm_pol_hold(xp);
 210
 211 out:
 212         read_unlock(&xp->lock);
 213         xfrm_pol_put(xp);
 214         return;
 215
 216 expired:
 217         read_unlock(&xp->lock);
 218         if (!xfrm_policy_delete(xp, dir))
 219                 km_policy_expired(xp, dir, 1);
 220         xfrm_pol_put(xp);
 221 }
 222
 223
 224 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 225  * SPD calls.
 226  */
 227
 228 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp)
 229 {
 230         struct xfrm_policy *policy;
 231
 232         policy = kmalloc(sizeof(struct xfrm_policy), gfp);
 233
 234         if (policy) {
 235                 memset(policy, 0, sizeof(struct xfrm_policy));
 236                 atomic_set(&policy->refcnt, 1);
 237                 rwlock_init(&policy->lock);
 238                 init_timer(&policy->timer);
 239                 policy->timer.data = (unsigned long)policy;
 240                 policy->timer.function = xfrm_policy_timer;
 241         }
 242         return policy;
 243 }
 244 EXPORT_SYMBOL(xfrm_policy_alloc);
 245
 246 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 247
 248 void __xfrm_policy_destroy(struct xfrm_policy *policy)
 249 {
 250         BUG_ON(!policy->dead);
 251
 252         BUG_ON(policy->bundles);
 253
 254         if (del_timer(&policy->timer))
 255                 BUG();
 256
 257         security_xfrm_policy_free(policy);
 258         kfree(policy);
 259 }
 260 EXPORT_SYMBOL(__xfrm_policy_destroy);
 261
 262 static void xfrm_policy_gc_kill(struct xfrm_policy *policy)
 263 {
 264         struct dst_entry *dst;
 265
 266         while ((dst = policy->bundles) != NULL) {
 267                 policy->bundles = dst->next;
 268                 dst_free(dst);
 269         }
 270
 271         if (del_timer(&policy->timer))
 272                 atomic_dec(&policy->refcnt);
 273
 274         if (atomic_read(&policy->refcnt) > 1)
 275                 flow_cache_flush();
 276
 277         xfrm_pol_put(policy);
 278 }
 279
 280 static void xfrm_policy_gc_task(void *data)
 281 {
 282         struct xfrm_policy *policy;
 283         struct list_head *entry, *tmp;
 284         struct list_head gc_list = LIST_HEAD_INIT(gc_list);
 285
 286         spin_lock_bh(&xfrm_policy_gc_lock);
 287         list_splice_init(&xfrm_policy_gc_list, &gc_list);
 288         spin_unlock_bh(&xfrm_policy_gc_lock);
 289
 290         list_for_each_safe(entry, tmp, &gc_list) {
 291                 policy = list_entry(entry, struct xfrm_policy, list);
 292                 xfrm_policy_gc_kill(policy);
 293         }
 294 }
 295
 296 /* Rule must be locked. Release descentant resources, announce
 297  * entry dead. The rule must be unlinked from lists to the moment.
 298  */
 299
 300 static void xfrm_policy_kill(struct xfrm_policy *policy)
 301 {
 302         int dead;
 303
 304         write_lock_bh(&policy->lock);
 305         dead = policy->dead;
 306         policy->dead = 1;
 307         write_unlock_bh(&policy->lock);
 308
 309         if (unlikely(dead)) {
 310                 WARN_ON(1);
 311                 return;
 312         }
 313
 314         spin_lock(&xfrm_policy_gc_lock);
 315         list_add(&policy->list, &xfrm_policy_gc_list);
 316         spin_unlock(&xfrm_policy_gc_lock);
 317
 318         schedule_work(&xfrm_policy_gc_work);
 319 }
 320
 321 /* Generate new index... KAME seems to generate them ordered by cost
 322  * of an absolute inpredictability of ordering of rules. This will not pass. */
 323 static u32 xfrm_gen_index(int dir)
 324 {
 325         u32 idx;
 326         struct xfrm_policy *p;
 327         static u32 idx_generator;
 328
 329         for (;;) {
 330                 idx = (idx_generator | dir);
 331                 idx_generator += 8;
 332                 if (idx == 0)
 333                         idx = 8;
 334                 for (p = xfrm_policy_list[dir]; p; p = p->next) {
 335                         if (p->index == idx)
 336                                 break;
 337                 }
 338                 if (!p)
 339                         return idx;
 340         }
 341 }
 342
 343 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 344 {
 345         struct xfrm_policy *pol, **p;
 346         struct xfrm_policy *delpol = NULL;
 347         struct xfrm_policy **newpos = NULL;
 348         struct dst_entry *gc_list;
 349
 350         write_lock_bh(&xfrm_policy_lock);
 351         for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL;) {
 352                 if (!delpol && memcmp(&policy->selector, &pol->selector, sizeof(pol->selector)) == 0 &&
 353                     xfrm_sec_ctx_match(pol->security, policy->security)) {
 354                         if (excl) {
 355                                 write_unlock_bh(&xfrm_policy_lock);
 356                                 return -EEXIST;
 357                         }
 358                         *p = pol->next;
 359                         delpol = pol;
 360                         if (policy->priority > pol->priority)
 361                                 continue;
 362                 } else if (policy->priority >= pol->priority) {
 363                         p = &pol->next;
 364                         continue;
 365                 }
 366                 if (!newpos)
 367                         newpos = p;
 368                 if (delpol)
 369                         break;
 370                 p = &pol->next;
 371         }
 372         if (newpos)
 373                 p = newpos;
 374         xfrm_pol_hold(policy);
 375         policy->next = *p;
 376         *p = policy;
 377         atomic_inc(&flow_cache_genid);
 378         policy->index = delpol ? delpol->index : xfrm_gen_index(dir);
 379         policy->curlft.add_time = (unsigned long)xtime.tv_sec;
 380         policy->curlft.use_time = 0;
 381         if (!mod_timer(&policy->timer, jiffies + HZ))
 382                 xfrm_pol_hold(policy);
 383         write_unlock_bh(&xfrm_policy_lock);
 384
 385         if (delpol)
 386                 xfrm_policy_kill(delpol);
 387
 388         read_lock_bh(&xfrm_policy_lock);
 389         gc_list = NULL;
 390         for (policy = policy->next; policy; policy = policy->next) {
 391                 struct dst_entry *dst;
 392
 393                 write_lock(&policy->lock);
 394                 dst = policy->bundles;
 395                 if (dst) {
 396                         struct dst_entry *tail = dst;
 397                         while (tail->next)
 398                                 tail = tail->next;
 399                         tail->next = gc_list;
 400                         gc_list = dst;
 401
 402                         policy->bundles = NULL;
 403                 }
 404                 write_unlock(&policy->lock);
 405         }
 406         read_unlock_bh(&xfrm_policy_lock);
 407
 408         while (gc_list) {
 409                 struct dst_entry *dst = gc_list;
 410
 411                 gc_list = dst->next;
 412                 dst_free(dst);
 413         }
 414
 415         return 0;
 416 }
 417 EXPORT_SYMBOL(xfrm_policy_insert);
 418
 419 struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel,
 420                                           struct xfrm_sec_ctx *ctx, int delete)
 421 {
 422         struct xfrm_policy *pol, **p;
 423
 424         write_lock_bh(&xfrm_policy_lock);
 425         for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) {
 426                 if ((memcmp(sel, &pol->selector, sizeof(*sel)) == 0) &&
 427                     (xfrm_sec_ctx_match(ctx, pol->security))) {
 428                         xfrm_pol_hold(pol);
 429                         if (delete)
 430                                 *p = pol->next;
 431                         break;
 432                 }
 433         }
 434         write_unlock_bh(&xfrm_policy_lock);
 435
 436         if (pol && delete) {
 437                 atomic_inc(&flow_cache_genid);
 438                 xfrm_policy_kill(pol);
 439         }
 440         return pol;
 441 }
 442 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 443
 444 struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete)
 445 {
 446         struct xfrm_policy *pol, **p;
 447
 448         write_lock_bh(&xfrm_policy_lock);
 449         for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) {
 450                 if (pol->index == id) {
 451                         xfrm_pol_hold(pol);
 452                         if (delete)
 453                                 *p = pol->next;
 454                         break;
 455                 }
 456         }
 457         write_unlock_bh(&xfrm_policy_lock);
 458
 459         if (pol && delete) {
 460                 atomic_inc(&flow_cache_genid);
 461                 xfrm_policy_kill(pol);
 462         }
 463         return pol;
 464 }
 465 EXPORT_SYMBOL(xfrm_policy_byid);
 466
 467 void xfrm_policy_flush(void)
 468 {
 469         struct xfrm_policy *xp;
 470         int dir;
 471
 472         write_lock_bh(&xfrm_policy_lock);
 473         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 474                 while ((xp = xfrm_policy_list[dir]) != NULL) {
 475                         xfrm_policy_list[dir] = xp->next;
 476                         write_unlock_bh(&xfrm_policy_lock);
 477
 478                         xfrm_policy_kill(xp);
 479
 480                         write_lock_bh(&xfrm_policy_lock);
 481                 }
 482         }
 483         atomic_inc(&flow_cache_genid);
 484         write_unlock_bh(&xfrm_policy_lock);
 485 }
 486 EXPORT_SYMBOL(xfrm_policy_flush);
 487
 488 int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*),
 489                      void *data)
 490 {
 491         struct xfrm_policy *xp;
 492         int dir;
 493         int count = 0;
 494         int error = 0;
 495
 496         read_lock_bh(&xfrm_policy_lock);
 497         for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
 498                 for (xp = xfrm_policy_list[dir]; xp; xp = xp->next)
 499                         count++;
 500         }
 501
 502         if (count == 0) {
 503                 error = -ENOENT;
 504                 goto out;
 505         }
 506
 507         for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) {
 508                 for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) {
 509                         error = func(xp, dir%XFRM_POLICY_MAX, --count, data);
 510                         if (error)
 511                                 goto out;
 512                 }
 513         }
 514
 515 out:
 516         read_unlock_bh(&xfrm_policy_lock);
 517         return error;
 518 }
 519 EXPORT_SYMBOL(xfrm_policy_walk);
 520
 521 /* Find policy to apply to this flow. */
 522
 523 static void xfrm_policy_lookup(struct flowi *fl, u32 sk_sid, u16 family, u8 dir,
 524                                void **objp, atomic_t **obj_refp)
 525 {
 526         struct xfrm_policy *pol;
 527
 528         read_lock_bh(&xfrm_policy_lock);
 529         for (pol = xfrm_policy_list[dir]; pol; pol = pol->next) {
 530                 struct xfrm_selector *sel = &pol->selector;
 531                 int match;
 532
 533                 if (pol->family != family)
 534                         continue;
 535
 536                 match = xfrm_selector_match(sel, fl, family);
 537
 538                 if (match) {
 539                         if (!security_xfrm_policy_lookup(pol, sk_sid, dir)) {
 540                                 xfrm_pol_hold(pol);
 541                                 break;
 542                         }
 543                 }
 544         }
 545         read_unlock_bh(&xfrm_policy_lock);
 546         if ((*objp = (void *) pol) != NULL)
 547                 *obj_refp = &pol->refcnt;
 548 }
 549
 550 static inline int policy_to_flow_dir(int dir)
 551 {
 552         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
 553             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
 554             XFRM_POLICY_FWD == FLOW_DIR_FWD)
 555                 return dir;
 556         switch (dir) {
 557         default:
 558         case XFRM_POLICY_IN:
 559                 return FLOW_DIR_IN;
 560         case XFRM_POLICY_OUT:
 561                 return FLOW_DIR_OUT;
 562         case XFRM_POLICY_FWD:
 563                 return FLOW_DIR_FWD;
 564         };
 565 }
 566
 567 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl, u32 sk_sid)
 568 {
 569         struct xfrm_policy *pol;
 570
 571         read_lock_bh(&xfrm_policy_lock);
 572         if ((pol = sk->sk_policy[dir]) != NULL) {
 573                 int match = xfrm_selector_match(&pol->selector, fl,
 574                                                 sk->sk_family);
 575                 int err = 0;
 576
 577                 if (match)
 578                   err = security_xfrm_policy_lookup(pol, sk_sid, policy_to_flow_dir(dir));
 579
 580                 if (match && !err)
 581                         xfrm_pol_hold(pol);
 582                 else
 583                         pol = NULL;
 584         }
 585         read_unlock_bh(&xfrm_policy_lock);
 586         return pol;
 587 }
 588
 589 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
 590 {
 591         pol->next = xfrm_policy_list[dir];
 592         xfrm_policy_list[dir] = pol;
 593         xfrm_pol_hold(pol);
 594 }
 595
 596 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 597                                                 int dir)
 598 {
 599         struct xfrm_policy **polp;
 600
 601         for (polp = &xfrm_policy_list[dir];
 602              *polp != NULL; polp = &(*polp)->next) {
 603                 if (*polp == pol) {
 604                         *polp = pol->next;
 605                         return pol;
 606                 }
 607         }
 608         return NULL;
 609 }
 610
 611 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
 612 {
 613         write_lock_bh(&xfrm_policy_lock);
 614         pol = __xfrm_policy_unlink(pol, dir);
 615         write_unlock_bh(&xfrm_policy_lock);
 616         if (pol) {
 617                 if (dir < XFRM_POLICY_MAX)
 618                         atomic_inc(&flow_cache_genid);
 619                 xfrm_policy_kill(pol);
 620                 return 0;
 621         }
 622         return -ENOENT;
 623 }
 624
 625 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
 626 {
 627         struct xfrm_policy *old_pol;
 628
 629         write_lock_bh(&xfrm_policy_lock);
 630         old_pol = sk->sk_policy[dir];
 631         sk->sk_policy[dir] = pol;
 632         if (pol) {
 633                 pol->curlft.add_time = (unsigned long)xtime.tv_sec;
 634                 pol->index = xfrm_gen_index(XFRM_POLICY_MAX+dir);
 635                 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
 636         }
 637         if (old_pol)
 638                 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
 639         write_unlock_bh(&xfrm_policy_lock);
 640
 641         if (old_pol) {
 642                 xfrm_policy_kill(old_pol);
 643         }
 644         return 0;
 645 }
 646
 647 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
 648 {
 649         struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC);
 650
 651         if (newp) {
 652                 newp->selector = old->selector;
 653                 if (security_xfrm_policy_clone(old, newp)) {
 654                         kfree(newp);
 655                         return NULL;  /* ENOMEM */
 656                 }
 657                 newp->lft = old->lft;
 658                 newp->curlft = old->curlft;
 659                 newp->action = old->action;
 660                 newp->flags = old->flags;
 661                 newp->xfrm_nr = old->xfrm_nr;
 662                 newp->index = old->index;
 663                 memcpy(newp->xfrm_vec, old->xfrm_vec,
 664                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
 665                 write_lock_bh(&xfrm_policy_lock);
 666                 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
 667                 write_unlock_bh(&xfrm_policy_lock);
 668                 xfrm_pol_put(newp);
 669         }
 670         return newp;
 671 }
 672
 673 int __xfrm_sk_clone_policy(struct sock *sk)
 674 {
 675         struct xfrm_policy *p0 = sk->sk_policy[0],
 676                            *p1 = sk->sk_policy[1];
 677
 678         sk->sk_policy[0] = sk->sk_policy[1] = NULL;
 679         if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
 680                 return -ENOMEM;
 681         if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
 682                 return -ENOMEM;
 683         return 0;
 684 }
 685
 686 /* Resolve list of templates for the flow, given policy. */
 687
 688 static int
 689 xfrm_tmpl_resolve(struct xfrm_policy *policy, struct flowi *fl,
 690                   struct xfrm_state **xfrm,
 691                   unsigned short family)
 692 {
 693         int nx;
 694         int i, error;
 695         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
 696         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
 697
 698         for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
 699                 struct xfrm_state *x;
 700                 xfrm_address_t *remote = daddr;
 701                 xfrm_address_t *local  = saddr;
 702                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
 703
 704                 if (tmpl->mode) {
 705                         remote = &tmpl->id.daddr;
 706                         local = &tmpl->saddr;
 707                 }
 708
 709                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
 710
 711                 if (x && x->km.state == XFRM_STATE_VALID) {
 712                         xfrm[nx++] = x;
 713                         daddr = remote;
 714                         saddr = local;
 715                         continue;
 716                 }
 717                 if (x) {
 718                         error = (x->km.state == XFRM_STATE_ERROR ?
 719                                  -EINVAL : -EAGAIN);
 720                         xfrm_state_put(x);
 721                 }
 722
 723                 if (!tmpl->optional)
 724                         goto fail;
 725         }
 726         return nx;
 727
 728 fail:
 729         for (nx--; nx>=0; nx--)
 730                 xfrm_state_put(xfrm[nx]);
 731         return error;
 732 }
 733
 734 /* Check that the bundle accepts the flow and its components are
 735  * still valid.
 736  */
 737
 738 static struct dst_entry *
 739 xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family)
 740 {
 741         struct dst_entry *x;
 742         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 743         if (unlikely(afinfo == NULL))
 744                 return ERR_PTR(-EINVAL);
 745         x = afinfo->find_bundle(fl, policy);
 746         xfrm_policy_put_afinfo(afinfo);
 747         return x;
 748 }
 749
 750 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
 751  * all the metrics... Shortly, bundle a bundle.
 752  */
 753
 754 static int
 755 xfrm_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx,
 756                    struct flowi *fl, struct dst_entry **dst_p,
 757                    unsigned short family)
 758 {
 759         int err;
 760         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 761         if (unlikely(afinfo == NULL))
 762                 return -EINVAL;
 763         err = afinfo->bundle_create(policy, xfrm, nx, fl, dst_p);
 764         xfrm_policy_put_afinfo(afinfo);
 765         return err;
 766 }
 767
 768
 769 static int stale_bundle(struct dst_entry *dst);
 770
 771 /* Main function: finds/creates a bundle for given flow.
 772  *
 773  * At the moment we eat a raw IP route. Mostly to speed up lookups
 774  * on interfaces with disabled IPsec.
 775  */
 776 int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl,
 777                 struct sock *sk, int flags)
 778 {
 779         struct xfrm_policy *policy;
 780         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
 781         struct dst_entry *dst, *dst_orig = *dst_p;
 782         int nx = 0;
 783         int err;
 784         u32 genid;
 785         u16 family = dst_orig->ops->family;
 786         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
 787         u32 sk_sid = security_sk_sid(sk, fl, dir);
 788 restart:
 789         genid = atomic_read(&flow_cache_genid);
 790         policy = NULL;
 791         if (sk && sk->sk_policy[1])
 792                 policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, sk_sid);
 793
 794         if (!policy) {
 795                 /* To accelerate a bit...  */
 796                 if ((dst_orig->flags & DST_NOXFRM) || !xfrm_policy_list[XFRM_POLICY_OUT])
 797                         return 0;
 798
 799                 policy = flow_cache_lookup(fl, sk_sid, family, dir,
 800                                            xfrm_policy_lookup);
 801         }
 802
 803         if (!policy)
 804                 return 0;
 805
 806         policy->curlft.use_time = (unsigned long)xtime.tv_sec;
 807
 808         switch (policy->action) {
 809         case XFRM_POLICY_BLOCK:
 810                 /* Prohibit the flow */
 811                 err = -EPERM;
 812                 goto error;
 813
 814         case XFRM_POLICY_ALLOW:
 815                 if (policy->xfrm_nr == 0) {
 816                         /* Flow passes not transformed. */
 817                         xfrm_pol_put(policy);
 818                         return 0;
 819                 }
 820
 821                 /* Try to find matching bundle.
 822                  *
 823                  * LATER: help from flow cache. It is optional, this
 824                  * is required only for output policy.
 825                  */
 826                 dst = xfrm_find_bundle(fl, policy, family);
 827                 if (IS_ERR(dst)) {
 828                         err = PTR_ERR(dst);
 829                         goto error;
 830                 }
 831
 832                 if (dst)
 833                         break;
 834
 835                 nx = xfrm_tmpl_resolve(policy, fl, xfrm, family);
 836
 837                 if (unlikely(nx<0)) {
 838                         err = nx;
 839                         if (err == -EAGAIN && flags) {
 840                                 DECLARE_WAITQUEUE(wait, current);
 841
 842                                 add_wait_queue(&km_waitq, &wait);
 843                                 set_current_state(TASK_INTERRUPTIBLE);
 844                                 schedule();
 845                                 set_current_state(TASK_RUNNING);
 846                                 remove_wait_queue(&km_waitq, &wait);
 847
 848                                 nx = xfrm_tmpl_resolve(policy, fl, xfrm, family);
 849
 850                                 if (nx == -EAGAIN && signal_pending(current)) {
 851                                         err = -ERESTART;
 852                                         goto error;
 853                                 }
 854                                 if (nx == -EAGAIN ||
 855                                     genid != atomic_read(&flow_cache_genid)) {
 856                                         xfrm_pol_put(policy);
 857                                         goto restart;
 858                                 }
 859                                 err = nx;
 860                         }
 861                         if (err < 0)
 862                                 goto error;
 863                 }
 864                 if (nx == 0) {
 865                         /* Flow passes not transformed. */
 866                         xfrm_pol_put(policy);
 867                         return 0;
 868                 }
 869
 870                 dst = dst_orig;
 871                 err = xfrm_bundle_create(policy, xfrm, nx, fl, &dst, family);
 872
 873                 if (unlikely(err)) {
 874                         int i;
 875                         for (i=0; i<nx; i++)
 876                                 xfrm_state_put(xfrm[i]);
 877                         goto error;
 878                 }
 879
 880                 write_lock_bh(&policy->lock);
 881                 if (unlikely(policy->dead || stale_bundle(dst))) {
 882                         /* Wow! While we worked on resolving, this
 883                          * policy has gone. Retry. It is not paranoia,
 884                          * we just cannot enlist new bundle to dead object.
 885                          * We can't enlist stable bundles either.
 886                          */
 887                         write_unlock_bh(&policy->lock);
 888
 889                         xfrm_pol_put(policy);
 890                         if (dst)
 891                                 dst_free(dst);
 892
 893                         err = -EHOSTUNREACH;
 894                         goto error;
 895                 }
 896                 dst->next = policy->bundles;
 897                 policy->bundles = dst;
 898                 dst_hold(dst);
 899                 write_unlock_bh(&policy->lock);
 900         }
 901         *dst_p = dst;
 902         dst_release(dst_orig);
 903         xfrm_pol_put(policy);
 904         return 0;
 905
 906 error:
 907         dst_release(dst_orig);
 908         xfrm_pol_put(policy);
 909         *dst_p = NULL;
 910         return err;
 911 }
 912 EXPORT_SYMBOL(xfrm_lookup);
 913
 914 /* When skb is transformed back to its "native" form, we have to
 915  * check policy restrictions. At the moment we make this in maximally
 916  * stupid way. Shame on me. :-) Of course, connected sockets must
 917  * have policy cached at them.
 918  */
 919
 920 static inline int
 921 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
 922               unsigned short family)
 923 {
 924         if (xfrm_state_kern(x))
 925                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, family);
 926         return  x->id.proto == tmpl->id.proto &&
 927                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
 928                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
 929                 x->props.mode == tmpl->mode &&
 930                 (tmpl->aalgos & (1<<x->props.aalgo)) &&
 931                 !(x->props.mode && xfrm_state_addr_cmp(tmpl, x, family));
 932 }
 933
 934 static inline int
 935 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
 936                unsigned short family)
 937 {
 938         int idx = start;
 939
 940         if (tmpl->optional) {
 941                 if (!tmpl->mode)
 942                         return start;
 943         } else
 944                 start = -1;
 945         for (; idx < sp->len; idx++) {
 946                 if (xfrm_state_ok(tmpl, sp->x[idx].xvec, family))
 947                         return ++idx;
 948                 if (sp->x[idx].xvec->props.mode)
 949                         break;
 950         }
 951         return start;
 952 }
 953
 954 int
 955 xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family)
 956 {
 957         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 958
 959         if (unlikely(afinfo == NULL))
 960                 return -EAFNOSUPPORT;
 961
 962         afinfo->decode_session(skb, fl);
 963         xfrm_policy_put_afinfo(afinfo);
 964         return 0;
 965 }
 966 EXPORT_SYMBOL(xfrm_decode_session);
 967
 968 static inline int secpath_has_tunnel(struct sec_path *sp, int k)
 969 {
 970         for (; k < sp->len; k++) {
 971                 if (sp->x[k].xvec->props.mode)
 972                         return 1;
 973         }
 974
 975         return 0;
 976 }
 977
 978 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 979                         unsigned short family)
 980 {
 981         struct xfrm_policy *pol;
 982         struct flowi fl;
 983         u8 fl_dir = policy_to_flow_dir(dir);
 984         u32 sk_sid;
 985
 986         if (xfrm_decode_session(skb, &fl, family) < 0)
 987                 return 0;
 988         nf_nat_decode_session(skb, &fl, family);
 989
 990         sk_sid = security_sk_sid(sk, &fl, fl_dir);
 991
 992         /* First, check used SA against their selectors. */
 993         if (skb->sp) {
 994                 int i;
 995
 996                 for (i=skb->sp->len-1; i>=0; i--) {
 997                         struct sec_decap_state *xvec = &(skb->sp->x[i]);
 998                         if (!xfrm_selector_match(&xvec->xvec->sel, &fl, family))
 999                                 return 0;
1000
1001                         /* If there is a post_input processor, try running it */
1002                         if (xvec->xvec->type->post_input &&
1003                             (xvec->xvec->type->post_input)(xvec->xvec,
1004                                                            &(xvec->decap),
1005                                                            skb) != 0)
1006                                 return 0;
1007                 }
1008         }
1009
1010         pol = NULL;
1011         if (sk && sk->sk_policy[dir])
1012                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, sk_sid);
1013
1014         if (!pol)
1015                 pol = flow_cache_lookup(&fl, sk_sid, family, fl_dir,
1016                                         xfrm_policy_lookup);
1017
1018         if (!pol)
1019                 return !skb->sp || !secpath_has_tunnel(skb->sp, 0);
1020
1021         pol->curlft.use_time = (unsigned long)xtime.tv_sec;
1022
1023         if (pol->action == XFRM_POLICY_ALLOW) {
1024                 struct sec_path *sp;
1025                 static struct sec_path dummy;
1026                 int i, k;
1027
1028                 if ((sp = skb->sp) == NULL)
1029                         sp = &dummy;
1030
1031                 /* For each tunnel xfrm, find the first matching tmpl.
1032                  * For each tmpl before that, find corresponding xfrm.
1033                  * Order is _important_. Later we will implement
1034                  * some barriers, but at the moment barriers
1035                  * are implied between each two transformations.
1036                  */
1037                 for (i = pol->xfrm_nr-1, k = 0; i >= 0; i--) {
1038                         k = xfrm_policy_ok(pol->xfrm_vec+i, sp, k, family);
1039                         if (k < 0)
1040                                 goto reject;
1041                 }
1042
1043                 if (secpath_has_tunnel(sp, k))
1044                         goto reject;
1045
1046                 xfrm_pol_put(pol);
1047                 return 1;
1048         }
1049
1050 reject:
1051         xfrm_pol_put(pol);
1052         return 0;
1053 }
1054 EXPORT_SYMBOL(__xfrm_policy_check);
1055
1056 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1057 {
1058         struct flowi fl;
1059
1060         if (xfrm_decode_session(skb, &fl, family) < 0)
1061                 return 0;
1062
1063         return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0;
1064 }
1065 EXPORT_SYMBOL(__xfrm_route_forward);
1066
1067 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
1068 {
1069         /* If it is marked obsolete, which is how we even get here,
1070          * then we have purged it from the policy bundle list and we
1071          * did that for a good reason.
1072          */
1073         return NULL;
1074 }
1075
1076 static int stale_bundle(struct dst_entry *dst)
1077 {
1078         return !xfrm_bundle_ok((struct xfrm_dst *)dst, NULL, AF_UNSPEC);
1079 }
1080
1081 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
1082 {
1083         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
1084                 dst->dev = &loopback_dev;
1085                 dev_hold(&loopback_dev);
1086                 dev_put(dev);
1087         }
1088 }
1089 EXPORT_SYMBOL(xfrm_dst_ifdown);
1090
1091 static void xfrm_link_failure(struct sk_buff *skb)
1092 {
1093         /* Impossible. Such dst must be popped before reaches point of failure. */
1094         return;
1095 }
1096
1097 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
1098 {
1099         if (dst) {
1100                 if (dst->obsolete) {
1101                         dst_release(dst);
1102                         dst = NULL;
1103                 }
1104         }
1105         return dst;
1106 }
1107
1108 static void xfrm_prune_bundles(int (*func)(struct dst_entry *))
1109 {
1110         int i;
1111         struct xfrm_policy *pol;
1112         struct dst_entry *dst, **dstp, *gc_list = NULL;
1113
1114         read_lock_bh(&xfrm_policy_lock);
1115         for (i=0; i<2*XFRM_POLICY_MAX; i++) {
1116                 for (pol = xfrm_policy_list[i]; pol; pol = pol->next) {
1117                         write_lock(&pol->lock);
1118                         dstp = &pol->bundles;
1119                         while ((dst=*dstp) != NULL) {
1120                                 if (func(dst)) {
1121                                         *dstp = dst->next;
1122                                         dst->next = gc_list;
1123                                         gc_list = dst;
1124                                 } else {
1125                                         dstp = &dst->next;
1126                                 }
1127                         }
1128                         write_unlock(&pol->lock);
1129                 }
1130         }
1131         read_unlock_bh(&xfrm_policy_lock);
1132
1133         while (gc_list) {
1134                 dst = gc_list;
1135                 gc_list = dst->next;
1136                 dst_free(dst);
1137         }
1138 }
1139
1140 static int unused_bundle(struct dst_entry *dst)
1141 {
1142         return !atomic_read(&dst->__refcnt);
1143 }
1144
1145 static void __xfrm_garbage_collect(void)
1146 {
1147         xfrm_prune_bundles(unused_bundle);
1148 }
1149
1150 int xfrm_flush_bundles(void)
1151 {
1152         xfrm_prune_bundles(stale_bundle);
1153         return 0;
1154 }
1155
1156 static int always_true(struct dst_entry *dst)
1157 {
1158         return 1;
1159 }
1160
1161 void xfrm_flush_all_bundles(void)
1162 {
1163         xfrm_prune_bundles(always_true);
1164 }
1165
1166 void xfrm_init_pmtu(struct dst_entry *dst)
1167 {
1168         do {
1169                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1170                 u32 pmtu, route_mtu_cached;
1171
1172                 pmtu = dst_mtu(dst->child);
1173                 xdst->child_mtu_cached = pmtu;
1174
1175                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
1176
1177                 route_mtu_cached = dst_mtu(xdst->route);
1178                 xdst->route_mtu_cached = route_mtu_cached;
1179
1180                 if (pmtu > route_mtu_cached)
1181                         pmtu = route_mtu_cached;
1182
1183                 dst->metrics[RTAX_MTU-1] = pmtu;
1184         } while ((dst = dst->next));
1185 }
1186
1187 EXPORT_SYMBOL(xfrm_init_pmtu);
1188
1189 /* Check that the bundle accepts the flow and its components are
1190  * still valid.
1191  */
1192
1193 int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family)
1194 {
1195         struct dst_entry *dst = &first->u.dst;
1196         struct xfrm_dst *last;
1197         u32 mtu;
1198
1199         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
1200             (dst->dev && !netif_running(dst->dev)))
1201                 return 0;
1202
1203         last = NULL;
1204
1205         do {
1206                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1207
1208                 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
1209                         return 0;
1210                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
1211                         return 0;
1212
1213                 mtu = dst_mtu(dst->child);
1214                 if (xdst->child_mtu_cached != mtu) {
1215                         last = xdst;
1216                         xdst->child_mtu_cached = mtu;
1217                 }
1218
1219                 if (!dst_check(xdst->route, xdst->route_cookie))
1220                         return 0;
1221                 mtu = dst_mtu(xdst->route);
1222                 if (xdst->route_mtu_cached != mtu) {
1223                         last = xdst;
1224                         xdst->route_mtu_cached = mtu;
1225                 }
1226
1227                 dst = dst->child;
1228         } while (dst->xfrm);
1229
1230         if (likely(!last))
1231                 return 1;
1232
1233         mtu = last->child_mtu_cached;
1234         for (;;) {
1235                 dst = &last->u.dst;
1236
1237                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
1238                 if (mtu > last->route_mtu_cached)
1239                         mtu = last->route_mtu_cached;
1240                 dst->metrics[RTAX_MTU-1] = mtu;
1241
1242                 if (last == first)
1243                         break;
1244
1245                 last = last->u.next;
1246                 last->child_mtu_cached = mtu;
1247         }
1248
1249         return 1;
1250 }
1251
1252 EXPORT_SYMBOL(xfrm_bundle_ok);
1253
1254 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
1255 {
1256         int err = 0;
1257         if (unlikely(afinfo == NULL))
1258                 return -EINVAL;
1259         if (unlikely(afinfo->family >= NPROTO))
1260                 return -EAFNOSUPPORT;
1261         write_lock(&xfrm_policy_afinfo_lock);
1262         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
1263                 err = -ENOBUFS;
1264         else {
1265                 struct dst_ops *dst_ops = afinfo->dst_ops;
1266                 if (likely(dst_ops->kmem_cachep == NULL))
1267                         dst_ops->kmem_cachep = xfrm_dst_cache;
1268                 if (likely(dst_ops->check == NULL))
1269                         dst_ops->check = xfrm_dst_check;
1270                 if (likely(dst_ops->negative_advice == NULL))
1271                         dst_ops->negative_advice = xfrm_negative_advice;
1272                 if (likely(dst_ops->link_failure == NULL))
1273                         dst_ops->link_failure = xfrm_link_failure;
1274                 if (likely(afinfo->garbage_collect == NULL))
1275                         afinfo->garbage_collect = __xfrm_garbage_collect;
1276                 xfrm_policy_afinfo[afinfo->family] = afinfo;
1277         }
1278         write_unlock(&xfrm_policy_afinfo_lock);
1279         return err;
1280 }
1281 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
1282
1283 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
1284 {
1285         int err = 0;
1286         if (unlikely(afinfo == NULL))
1287                 return -EINVAL;
1288         if (unlikely(afinfo->family >= NPROTO))
1289                 return -EAFNOSUPPORT;
1290         write_lock(&xfrm_policy_afinfo_lock);
1291         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
1292                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
1293                         err = -EINVAL;
1294                 else {
1295                         struct dst_ops *dst_ops = afinfo->dst_ops;
1296                         xfrm_policy_afinfo[afinfo->family] = NULL;
1297                         dst_ops->kmem_cachep = NULL;
1298                         dst_ops->check = NULL;
1299                         dst_ops->negative_advice = NULL;
1300                         dst_ops->link_failure = NULL;
1301                         afinfo->garbage_collect = NULL;
1302                 }
1303         }
1304         write_unlock(&xfrm_policy_afinfo_lock);
1305         return err;
1306 }
1307 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
1308
1309 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
1310 {
1311         struct xfrm_policy_afinfo *afinfo;
1312         if (unlikely(family >= NPROTO))
1313                 return NULL;
1314         read_lock(&xfrm_policy_afinfo_lock);
1315         afinfo = xfrm_policy_afinfo[family];
1316         if (likely(afinfo != NULL))
1317                 read_lock(&afinfo->lock);
1318         read_unlock(&xfrm_policy_afinfo_lock);
1319         return afinfo;
1320 }
1321
1322 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
1323 {
1324         if (unlikely(afinfo == NULL))
1325                 return;
1326         read_unlock(&afinfo->lock);
1327 }
1328
1329 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
1330 {
1331         switch (event) {
1332         case NETDEV_DOWN:
1333                 xfrm_flush_bundles();
1334         }
1335         return NOTIFY_DONE;
1336 }
1337
1338 static struct notifier_block xfrm_dev_notifier = {
1339         xfrm_dev_event,
1340         NULL,
1341         0
1342 };
1343
1344 static void __init xfrm_policy_init(void)
1345 {
1346         xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
1347                                            sizeof(struct xfrm_dst),
1348                                            0, SLAB_HWCACHE_ALIGN,
1349                                            NULL, NULL);
1350         if (!xfrm_dst_cache)
1351                 panic("XFRM: failed to allocate xfrm_dst_cache\n");
1352
1353         INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task, NULL);
1354         register_netdevice_notifier(&xfrm_dev_notifier);
1355 }
1356
1357 void __init xfrm_init(void)
1358 {
1359         xfrm_state_init();
1360         xfrm_policy_init();
1361         xfrm_input_init();
1362 }
1363