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/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/audit.h>
  28 #include <net/dst.h>
  29 #include <net/flow.h>
  30 #include <net/xfrm.h>
  31 #include <net/ip.h>
  32 #ifdef CONFIG_XFRM_STATISTICS
  33 #include <net/snmp.h>
  34 #endif
  35
  36 #include "xfrm_hash.h"
  37
  38 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  39 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  40 #define XFRM_MAX_QUEUE_LEN      100
  41
  42 struct xfrm_flo {
  43         struct dst_entry *dst_orig;
  44         u8 flags;
  45 };
  46
  47 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
  48 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
  49                                                 __read_mostly;
  50
  51 static struct kmem_cache *xfrm_dst_cache __read_mostly;
  52 static __read_mostly seqcount_t xfrm_policy_hash_generation;
  53
  54 static void xfrm_init_pmtu(struct dst_entry *dst);
  55 static int stale_bundle(struct dst_entry *dst);
  56 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
  57 static void xfrm_policy_queue_process(unsigned long arg);
  58
  59 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
  60 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
  61                                                 int dir);
  62
  63 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
  64 {
  65         return atomic_inc_not_zero(&policy->refcnt);
  66 }
  67
  68 static inline bool
  69 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  70 {
  71         const struct flowi4 *fl4 = &fl->u.ip4;
  72
  73         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
  74                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
  75                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
  76                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
  77                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
  78                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
  79 }
  80
  81 static inline bool
  82 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  83 {
  84         const struct flowi6 *fl6 = &fl->u.ip6;
  85
  86         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
  87                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
  88                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
  89                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
  90                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
  91                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
  92 }
  93
  94 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
  95                          unsigned short family)
  96 {
  97         switch (family) {
  98         case AF_INET:
  99                 return __xfrm4_selector_match(sel, fl);
 100         case AF_INET6:
 101                 return __xfrm6_selector_match(sel, fl);
 102         }
 103         return false;
 104 }
 105
 106 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 107 {
 108         const struct xfrm_policy_afinfo *afinfo;
 109
 110         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 111                 return NULL;
 112         rcu_read_lock();
 113         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 114         if (unlikely(!afinfo))
 115                 rcu_read_unlock();
 116         return afinfo;
 117 }
 118
 119 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net,
 120                                                   int tos, int oif,
 121                                                   const xfrm_address_t *saddr,
 122                                                   const xfrm_address_t *daddr,
 123                                                   int family)
 124 {
 125         const struct xfrm_policy_afinfo *afinfo;
 126         struct dst_entry *dst;
 127
 128         afinfo = xfrm_policy_get_afinfo(family);
 129         if (unlikely(afinfo == NULL))
 130                 return ERR_PTR(-EAFNOSUPPORT);
 131
 132         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr);
 133
 134         rcu_read_unlock();
 135
 136         return dst;
 137 }
 138
 139 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 140                                                 int tos, int oif,
 141                                                 xfrm_address_t *prev_saddr,
 142                                                 xfrm_address_t *prev_daddr,
 143                                                 int family)
 144 {
 145         struct net *net = xs_net(x);
 146         xfrm_address_t *saddr = &x->props.saddr;
 147         xfrm_address_t *daddr = &x->id.daddr;
 148         struct dst_entry *dst;
 149
 150         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 151                 saddr = x->coaddr;
 152                 daddr = prev_daddr;
 153         }
 154         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 155                 saddr = prev_saddr;
 156                 daddr = x->coaddr;
 157         }
 158
 159         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family);
 160
 161         if (!IS_ERR(dst)) {
 162                 if (prev_saddr != saddr)
 163                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 164                 if (prev_daddr != daddr)
 165                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 166         }
 167
 168         return dst;
 169 }
 170
 171 static inline unsigned long make_jiffies(long secs)
 172 {
 173         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 174                 return MAX_SCHEDULE_TIMEOUT-1;
 175         else
 176                 return secs*HZ;
 177 }
 178
 179 static void xfrm_policy_timer(unsigned long data)
 180 {
 181         struct xfrm_policy *xp = (struct xfrm_policy *)data;
 182         unsigned long now = get_seconds();
 183         long next = LONG_MAX;
 184         int warn = 0;
 185         int dir;
 186
 187         read_lock(&xp->lock);
 188
 189         if (unlikely(xp->walk.dead))
 190                 goto out;
 191
 192         dir = xfrm_policy_id2dir(xp->index);
 193
 194         if (xp->lft.hard_add_expires_seconds) {
 195                 long tmo = xp->lft.hard_add_expires_seconds +
 196                         xp->curlft.add_time - now;
 197                 if (tmo <= 0)
 198                         goto expired;
 199                 if (tmo < next)
 200                         next = tmo;
 201         }
 202         if (xp->lft.hard_use_expires_seconds) {
 203                 long tmo = xp->lft.hard_use_expires_seconds +
 204                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 205                 if (tmo <= 0)
 206                         goto expired;
 207                 if (tmo < next)
 208                         next = tmo;
 209         }
 210         if (xp->lft.soft_add_expires_seconds) {
 211                 long tmo = xp->lft.soft_add_expires_seconds +
 212                         xp->curlft.add_time - now;
 213                 if (tmo <= 0) {
 214                         warn = 1;
 215                         tmo = XFRM_KM_TIMEOUT;
 216                 }
 217                 if (tmo < next)
 218                         next = tmo;
 219         }
 220         if (xp->lft.soft_use_expires_seconds) {
 221                 long tmo = xp->lft.soft_use_expires_seconds +
 222                         (xp->curlft.use_time ? : 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
 231         if (warn)
 232                 km_policy_expired(xp, dir, 0, 0);
 233         if (next != LONG_MAX &&
 234             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 235                 xfrm_pol_hold(xp);
 236
 237 out:
 238         read_unlock(&xp->lock);
 239         xfrm_pol_put(xp);
 240         return;
 241
 242 expired:
 243         read_unlock(&xp->lock);
 244         if (!xfrm_policy_delete(xp, dir))
 245                 km_policy_expired(xp, dir, 1, 0);
 246         xfrm_pol_put(xp);
 247 }
 248
 249 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
 250 {
 251         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 252
 253         if (unlikely(pol->walk.dead))
 254                 flo = NULL;
 255         else
 256                 xfrm_pol_hold(pol);
 257
 258         return flo;
 259 }
 260
 261 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
 262 {
 263         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 264
 265         return !pol->walk.dead;
 266 }
 267
 268 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
 269 {
 270         xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
 271 }
 272
 273 static const struct flow_cache_ops xfrm_policy_fc_ops = {
 274         .get = xfrm_policy_flo_get,
 275         .check = xfrm_policy_flo_check,
 276         .delete = xfrm_policy_flo_delete,
 277 };
 278
 279 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 280  * SPD calls.
 281  */
 282
 283 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 284 {
 285         struct xfrm_policy *policy;
 286
 287         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 288
 289         if (policy) {
 290                 write_pnet(&policy->xp_net, net);
 291                 INIT_LIST_HEAD(&policy->walk.all);
 292                 INIT_HLIST_NODE(&policy->bydst);
 293                 INIT_HLIST_NODE(&policy->byidx);
 294                 rwlock_init(&policy->lock);
 295                 atomic_set(&policy->refcnt, 1);
 296                 skb_queue_head_init(&policy->polq.hold_queue);
 297                 setup_timer(&policy->timer, xfrm_policy_timer,
 298                                 (unsigned long)policy);
 299                 setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
 300                             (unsigned long)policy);
 301                 policy->flo.ops = &xfrm_policy_fc_ops;
 302         }
 303         return policy;
 304 }
 305 EXPORT_SYMBOL(xfrm_policy_alloc);
 306
 307 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 308 {
 309         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 310
 311         security_xfrm_policy_free(policy->security);
 312         kfree(policy);
 313 }
 314
 315 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 316
 317 void xfrm_policy_destroy(struct xfrm_policy *policy)
 318 {
 319         BUG_ON(!policy->walk.dead);
 320
 321         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 322                 BUG();
 323
 324         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 325 }
 326 EXPORT_SYMBOL(xfrm_policy_destroy);
 327
 328 /* Rule must be locked. Release descendant resources, announce
 329  * entry dead. The rule must be unlinked from lists to the moment.
 330  */
 331
 332 static void xfrm_policy_kill(struct xfrm_policy *policy)
 333 {
 334         policy->walk.dead = 1;
 335
 336         atomic_inc(&policy->genid);
 337
 338         if (del_timer(&policy->polq.hold_timer))
 339                 xfrm_pol_put(policy);
 340         skb_queue_purge(&policy->polq.hold_queue);
 341
 342         if (del_timer(&policy->timer))
 343                 xfrm_pol_put(policy);
 344
 345         xfrm_pol_put(policy);
 346 }
 347
 348 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 349
 350 static inline unsigned int idx_hash(struct net *net, u32 index)
 351 {
 352         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 353 }
 354
 355 /* calculate policy hash thresholds */
 356 static void __get_hash_thresh(struct net *net,
 357                               unsigned short family, int dir,
 358                               u8 *dbits, u8 *sbits)
 359 {
 360         switch (family) {
 361         case AF_INET:
 362                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 363                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 364                 break;
 365
 366         case AF_INET6:
 367                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 368                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 369                 break;
 370
 371         default:
 372                 *dbits = 0;
 373                 *sbits = 0;
 374         }
 375 }
 376
 377 static struct hlist_head *policy_hash_bysel(struct net *net,
 378                                             const struct xfrm_selector *sel,
 379                                             unsigned short family, int dir)
 380 {
 381         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 382         unsigned int hash;
 383         u8 dbits;
 384         u8 sbits;
 385
 386         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 387         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 388
 389         if (hash == hmask + 1)
 390                 return &net->xfrm.policy_inexact[dir];
 391
 392         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 393                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 394 }
 395
 396 static struct hlist_head *policy_hash_direct(struct net *net,
 397                                              const xfrm_address_t *daddr,
 398                                              const xfrm_address_t *saddr,
 399                                              unsigned short family, int dir)
 400 {
 401         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 402         unsigned int hash;
 403         u8 dbits;
 404         u8 sbits;
 405
 406         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 407         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 408
 409         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 410                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 411 }
 412
 413 static void xfrm_dst_hash_transfer(struct net *net,
 414                                    struct hlist_head *list,
 415                                    struct hlist_head *ndsttable,
 416                                    unsigned int nhashmask,
 417                                    int dir)
 418 {
 419         struct hlist_node *tmp, *entry0 = NULL;
 420         struct xfrm_policy *pol;
 421         unsigned int h0 = 0;
 422         u8 dbits;
 423         u8 sbits;
 424
 425 redo:
 426         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 427                 unsigned int h;
 428
 429                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 430                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 431                                 pol->family, nhashmask, dbits, sbits);
 432                 if (!entry0) {
 433                         hlist_del_rcu(&pol->bydst);
 434                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 435                         h0 = h;
 436                 } else {
 437                         if (h != h0)
 438                                 continue;
 439                         hlist_del_rcu(&pol->bydst);
 440                         hlist_add_behind_rcu(&pol->bydst, entry0);
 441                 }
 442                 entry0 = &pol->bydst;
 443         }
 444         if (!hlist_empty(list)) {
 445                 entry0 = NULL;
 446                 goto redo;
 447         }
 448 }
 449
 450 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 451                                    struct hlist_head *nidxtable,
 452                                    unsigned int nhashmask)
 453 {
 454         struct hlist_node *tmp;
 455         struct xfrm_policy *pol;
 456
 457         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 458                 unsigned int h;
 459
 460                 h = __idx_hash(pol->index, nhashmask);
 461                 hlist_add_head(&pol->byidx, nidxtable+h);
 462         }
 463 }
 464
 465 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 466 {
 467         return ((old_hmask + 1) << 1) - 1;
 468 }
 469
 470 static void xfrm_bydst_resize(struct net *net, int dir)
 471 {
 472         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 473         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 474         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 475         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 476         struct hlist_head *odst;
 477         int i;
 478
 479         if (!ndst)
 480                 return;
 481
 482         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 483         write_seqcount_begin(&xfrm_policy_hash_generation);
 484
 485         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 486                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 487
 488         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 489                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 490
 491         for (i = hmask; i >= 0; i--)
 492                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 493
 494         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 495         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 496
 497         write_seqcount_end(&xfrm_policy_hash_generation);
 498         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 499
 500         synchronize_rcu();
 501
 502         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 503 }
 504
 505 static void xfrm_byidx_resize(struct net *net, int total)
 506 {
 507         unsigned int hmask = net->xfrm.policy_idx_hmask;
 508         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 509         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 510         struct hlist_head *oidx = net->xfrm.policy_byidx;
 511         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 512         int i;
 513
 514         if (!nidx)
 515                 return;
 516
 517         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 518
 519         for (i = hmask; i >= 0; i--)
 520                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 521
 522         net->xfrm.policy_byidx = nidx;
 523         net->xfrm.policy_idx_hmask = nhashmask;
 524
 525         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 526
 527         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 528 }
 529
 530 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 531 {
 532         unsigned int cnt = net->xfrm.policy_count[dir];
 533         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 534
 535         if (total)
 536                 *total += cnt;
 537
 538         if ((hmask + 1) < xfrm_policy_hashmax &&
 539             cnt > hmask)
 540                 return 1;
 541
 542         return 0;
 543 }
 544
 545 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 546 {
 547         unsigned int hmask = net->xfrm.policy_idx_hmask;
 548
 549         if ((hmask + 1) < xfrm_policy_hashmax &&
 550             total > hmask)
 551                 return 1;
 552
 553         return 0;
 554 }
 555
 556 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 557 {
 558         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 559         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 560         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 561         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 562         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 563         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 564         si->spdhcnt = net->xfrm.policy_idx_hmask;
 565         si->spdhmcnt = xfrm_policy_hashmax;
 566 }
 567 EXPORT_SYMBOL(xfrm_spd_getinfo);
 568
 569 static DEFINE_MUTEX(hash_resize_mutex);
 570 static void xfrm_hash_resize(struct work_struct *work)
 571 {
 572         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 573         int dir, total;
 574
 575         mutex_lock(&hash_resize_mutex);
 576
 577         total = 0;
 578         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 579                 if (xfrm_bydst_should_resize(net, dir, &total))
 580                         xfrm_bydst_resize(net, dir);
 581         }
 582         if (xfrm_byidx_should_resize(net, total))
 583                 xfrm_byidx_resize(net, total);
 584
 585         mutex_unlock(&hash_resize_mutex);
 586 }
 587
 588 static void xfrm_hash_rebuild(struct work_struct *work)
 589 {
 590         struct net *net = container_of(work, struct net,
 591                                        xfrm.policy_hthresh.work);
 592         unsigned int hmask;
 593         struct xfrm_policy *pol;
 594         struct xfrm_policy *policy;
 595         struct hlist_head *chain;
 596         struct hlist_head *odst;
 597         struct hlist_node *newpos;
 598         int i;
 599         int dir;
 600         unsigned seq;
 601         u8 lbits4, rbits4, lbits6, rbits6;
 602
 603         mutex_lock(&hash_resize_mutex);
 604
 605         /* read selector prefixlen thresholds */
 606         do {
 607                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
 608
 609                 lbits4 = net->xfrm.policy_hthresh.lbits4;
 610                 rbits4 = net->xfrm.policy_hthresh.rbits4;
 611                 lbits6 = net->xfrm.policy_hthresh.lbits6;
 612                 rbits6 = net->xfrm.policy_hthresh.rbits6;
 613         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
 614
 615         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 616
 617         /* reset the bydst and inexact table in all directions */
 618         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 619                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
 620                 hmask = net->xfrm.policy_bydst[dir].hmask;
 621                 odst = net->xfrm.policy_bydst[dir].table;
 622                 for (i = hmask; i >= 0; i--)
 623                         INIT_HLIST_HEAD(odst + i);
 624                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
 625                         /* dir out => dst = remote, src = local */
 626                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
 627                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
 628                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
 629                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
 630                 } else {
 631                         /* dir in/fwd => dst = local, src = remote */
 632                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
 633                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
 634                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
 635                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
 636                 }
 637         }
 638
 639         /* re-insert all policies by order of creation */
 640         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 641                 if (xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
 642                         /* skip socket policies */
 643                         continue;
 644                 }
 645                 newpos = NULL;
 646                 chain = policy_hash_bysel(net, &policy->selector,
 647                                           policy->family,
 648                                           xfrm_policy_id2dir(policy->index));
 649                 hlist_for_each_entry(pol, chain, bydst) {
 650                         if (policy->priority >= pol->priority)
 651                                 newpos = &pol->bydst;
 652                         else
 653                                 break;
 654                 }
 655                 if (newpos)
 656                         hlist_add_behind(&policy->bydst, newpos);
 657                 else
 658                         hlist_add_head(&policy->bydst, chain);
 659         }
 660
 661         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 662
 663         mutex_unlock(&hash_resize_mutex);
 664 }
 665
 666 void xfrm_policy_hash_rebuild(struct net *net)
 667 {
 668         schedule_work(&net->xfrm.policy_hthresh.work);
 669 }
 670 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
 671
 672 /* Generate new index... KAME seems to generate them ordered by cost
 673  * of an absolute inpredictability of ordering of rules. This will not pass. */
 674 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
 675 {
 676         static u32 idx_generator;
 677
 678         for (;;) {
 679                 struct hlist_head *list;
 680                 struct xfrm_policy *p;
 681                 u32 idx;
 682                 int found;
 683
 684                 if (!index) {
 685                         idx = (idx_generator | dir);
 686                         idx_generator += 8;
 687                 } else {
 688                         idx = index;
 689                         index = 0;
 690                 }
 691
 692                 if (idx == 0)
 693                         idx = 8;
 694                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 695                 found = 0;
 696                 hlist_for_each_entry(p, list, byidx) {
 697                         if (p->index == idx) {
 698                                 found = 1;
 699                                 break;
 700                         }
 701                 }
 702                 if (!found)
 703                         return idx;
 704         }
 705 }
 706
 707 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 708 {
 709         u32 *p1 = (u32 *) s1;
 710         u32 *p2 = (u32 *) s2;
 711         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 712         int i;
 713
 714         for (i = 0; i < len; i++) {
 715                 if (p1[i] != p2[i])
 716                         return 1;
 717         }
 718
 719         return 0;
 720 }
 721
 722 static void xfrm_policy_requeue(struct xfrm_policy *old,
 723                                 struct xfrm_policy *new)
 724 {
 725         struct xfrm_policy_queue *pq = &old->polq;
 726         struct sk_buff_head list;
 727
 728         if (skb_queue_empty(&pq->hold_queue))
 729                 return;
 730
 731         __skb_queue_head_init(&list);
 732
 733         spin_lock_bh(&pq->hold_queue.lock);
 734         skb_queue_splice_init(&pq->hold_queue, &list);
 735         if (del_timer(&pq->hold_timer))
 736                 xfrm_pol_put(old);
 737         spin_unlock_bh(&pq->hold_queue.lock);
 738
 739         pq = &new->polq;
 740
 741         spin_lock_bh(&pq->hold_queue.lock);
 742         skb_queue_splice(&list, &pq->hold_queue);
 743         pq->timeout = XFRM_QUEUE_TMO_MIN;
 744         if (!mod_timer(&pq->hold_timer, jiffies))
 745                 xfrm_pol_hold(new);
 746         spin_unlock_bh(&pq->hold_queue.lock);
 747 }
 748
 749 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
 750                                    struct xfrm_policy *pol)
 751 {
 752         u32 mark = policy->mark.v & policy->mark.m;
 753
 754         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
 755                 return true;
 756
 757         if ((mark & pol->mark.m) == pol->mark.v &&
 758             policy->priority == pol->priority)
 759                 return true;
 760
 761         return false;
 762 }
 763
 764 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 765 {
 766         struct net *net = xp_net(policy);
 767         struct xfrm_policy *pol;
 768         struct xfrm_policy *delpol;
 769         struct hlist_head *chain;
 770         struct hlist_node *newpos;
 771
 772         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 773         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 774         delpol = NULL;
 775         newpos = NULL;
 776         hlist_for_each_entry(pol, chain, bydst) {
 777                 if (pol->type == policy->type &&
 778                     !selector_cmp(&pol->selector, &policy->selector) &&
 779                     xfrm_policy_mark_match(policy, pol) &&
 780                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 781                     !WARN_ON(delpol)) {
 782                         if (excl) {
 783                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 784                                 return -EEXIST;
 785                         }
 786                         delpol = pol;
 787                         if (policy->priority > pol->priority)
 788                                 continue;
 789                 } else if (policy->priority >= pol->priority) {
 790                         newpos = &pol->bydst;
 791                         continue;
 792                 }
 793                 if (delpol)
 794                         break;
 795         }
 796         if (newpos)
 797                 hlist_add_behind(&policy->bydst, newpos);
 798         else
 799                 hlist_add_head(&policy->bydst, chain);
 800         __xfrm_policy_link(policy, dir);
 801         atomic_inc(&net->xfrm.flow_cache_genid);
 802
 803         /* After previous checking, family can either be AF_INET or AF_INET6 */
 804         if (policy->family == AF_INET)
 805                 rt_genid_bump_ipv4(net);
 806         else
 807                 rt_genid_bump_ipv6(net);
 808
 809         if (delpol) {
 810                 xfrm_policy_requeue(delpol, policy);
 811                 __xfrm_policy_unlink(delpol, dir);
 812         }
 813         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
 814         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 815         policy->curlft.add_time = get_seconds();
 816         policy->curlft.use_time = 0;
 817         if (!mod_timer(&policy->timer, jiffies + HZ))
 818                 xfrm_pol_hold(policy);
 819         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 820
 821         if (delpol)
 822                 xfrm_policy_kill(delpol);
 823         else if (xfrm_bydst_should_resize(net, dir, NULL))
 824                 schedule_work(&net->xfrm.policy_hash_work);
 825
 826         return 0;
 827 }
 828 EXPORT_SYMBOL(xfrm_policy_insert);
 829
 830 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
 831                                           int dir, struct xfrm_selector *sel,
 832                                           struct xfrm_sec_ctx *ctx, int delete,
 833                                           int *err)
 834 {
 835         struct xfrm_policy *pol, *ret;
 836         struct hlist_head *chain;
 837
 838         *err = 0;
 839         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 840         chain = policy_hash_bysel(net, sel, sel->family, dir);
 841         ret = NULL;
 842         hlist_for_each_entry(pol, chain, bydst) {
 843                 if (pol->type == type &&
 844                     (mark & pol->mark.m) == pol->mark.v &&
 845                     !selector_cmp(sel, &pol->selector) &&
 846                     xfrm_sec_ctx_match(ctx, pol->security)) {
 847                         xfrm_pol_hold(pol);
 848                         if (delete) {
 849                                 *err = security_xfrm_policy_delete(
 850                                                                 pol->security);
 851                                 if (*err) {
 852                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 853                                         return pol;
 854                                 }
 855                                 __xfrm_policy_unlink(pol, dir);
 856                         }
 857                         ret = pol;
 858                         break;
 859                 }
 860         }
 861         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 862
 863         if (ret && delete)
 864                 xfrm_policy_kill(ret);
 865         return ret;
 866 }
 867 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 868
 869 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
 870                                      int dir, u32 id, int delete, int *err)
 871 {
 872         struct xfrm_policy *pol, *ret;
 873         struct hlist_head *chain;
 874
 875         *err = -ENOENT;
 876         if (xfrm_policy_id2dir(id) != dir)
 877                 return NULL;
 878
 879         *err = 0;
 880         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 881         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 882         ret = NULL;
 883         hlist_for_each_entry(pol, chain, byidx) {
 884                 if (pol->type == type && pol->index == id &&
 885                     (mark & pol->mark.m) == pol->mark.v) {
 886                         xfrm_pol_hold(pol);
 887                         if (delete) {
 888                                 *err = security_xfrm_policy_delete(
 889                                                                 pol->security);
 890                                 if (*err) {
 891                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 892                                         return pol;
 893                                 }
 894                                 __xfrm_policy_unlink(pol, dir);
 895                         }
 896                         ret = pol;
 897                         break;
 898                 }
 899         }
 900         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 901
 902         if (ret && delete)
 903                 xfrm_policy_kill(ret);
 904         return ret;
 905 }
 906 EXPORT_SYMBOL(xfrm_policy_byid);
 907
 908 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 909 static inline int
 910 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 911 {
 912         int dir, err = 0;
 913
 914         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 915                 struct xfrm_policy *pol;
 916                 int i;
 917
 918                 hlist_for_each_entry(pol,
 919                                      &net->xfrm.policy_inexact[dir], bydst) {
 920                         if (pol->type != type)
 921                                 continue;
 922                         err = security_xfrm_policy_delete(pol->security);
 923                         if (err) {
 924                                 xfrm_audit_policy_delete(pol, 0, task_valid);
 925                                 return err;
 926                         }
 927                 }
 928                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 929                         hlist_for_each_entry(pol,
 930                                              net->xfrm.policy_bydst[dir].table + i,
 931                                              bydst) {
 932                                 if (pol->type != type)
 933                                         continue;
 934                                 err = security_xfrm_policy_delete(
 935                                                                 pol->security);
 936                                 if (err) {
 937                                         xfrm_audit_policy_delete(pol, 0,
 938                                                                  task_valid);
 939                                         return err;
 940                                 }
 941                         }
 942                 }
 943         }
 944         return err;
 945 }
 946 #else
 947 static inline int
 948 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 949 {
 950         return 0;
 951 }
 952 #endif
 953
 954 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
 955 {
 956         int dir, err = 0, cnt = 0;
 957
 958         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 959
 960         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
 961         if (err)
 962                 goto out;
 963
 964         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 965                 struct xfrm_policy *pol;
 966                 int i;
 967
 968         again1:
 969                 hlist_for_each_entry(pol,
 970                                      &net->xfrm.policy_inexact[dir], bydst) {
 971                         if (pol->type != type)
 972                                 continue;
 973                         __xfrm_policy_unlink(pol, dir);
 974                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 975                         cnt++;
 976
 977                         xfrm_audit_policy_delete(pol, 1, task_valid);
 978
 979                         xfrm_policy_kill(pol);
 980
 981                         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 982                         goto again1;
 983                 }
 984
 985                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 986         again2:
 987                         hlist_for_each_entry(pol,
 988                                              net->xfrm.policy_bydst[dir].table + i,
 989                                              bydst) {
 990                                 if (pol->type != type)
 991                                         continue;
 992                                 __xfrm_policy_unlink(pol, dir);
 993                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 994                                 cnt++;
 995
 996                                 xfrm_audit_policy_delete(pol, 1, task_valid);
 997                                 xfrm_policy_kill(pol);
 998
 999                                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1000                                 goto again2;
1001                         }
1002                 }
1003
1004         }
1005         if (!cnt)
1006                 err = -ESRCH;
1007 out:
1008         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1009         return err;
1010 }
1011 EXPORT_SYMBOL(xfrm_policy_flush);
1012
1013 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1014                      int (*func)(struct xfrm_policy *, int, int, void*),
1015                      void *data)
1016 {
1017         struct xfrm_policy *pol;
1018         struct xfrm_policy_walk_entry *x;
1019         int error = 0;
1020
1021         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1022             walk->type != XFRM_POLICY_TYPE_ANY)
1023                 return -EINVAL;
1024
1025         if (list_empty(&walk->walk.all) && walk->seq != 0)
1026                 return 0;
1027
1028         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1029         if (list_empty(&walk->walk.all))
1030                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1031         else
1032                 x = list_first_entry(&walk->walk.all,
1033                                      struct xfrm_policy_walk_entry, all);
1034
1035         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1036                 if (x->dead)
1037                         continue;
1038                 pol = container_of(x, struct xfrm_policy, walk);
1039                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1040                     walk->type != pol->type)
1041                         continue;
1042                 error = func(pol, xfrm_policy_id2dir(pol->index),
1043                              walk->seq, data);
1044                 if (error) {
1045                         list_move_tail(&walk->walk.all, &x->all);
1046                         goto out;
1047                 }
1048                 walk->seq++;
1049         }
1050         if (walk->seq == 0) {
1051                 error = -ENOENT;
1052                 goto out;
1053         }
1054         list_del_init(&walk->walk.all);
1055 out:
1056         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1057         return error;
1058 }
1059 EXPORT_SYMBOL(xfrm_policy_walk);
1060
1061 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1062 {
1063         INIT_LIST_HEAD(&walk->walk.all);
1064         walk->walk.dead = 1;
1065         walk->type = type;
1066         walk->seq = 0;
1067 }
1068 EXPORT_SYMBOL(xfrm_policy_walk_init);
1069
1070 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1071 {
1072         if (list_empty(&walk->walk.all))
1073                 return;
1074
1075         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1076         list_del(&walk->walk.all);
1077         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1078 }
1079 EXPORT_SYMBOL(xfrm_policy_walk_done);
1080
1081 /*
1082  * Find policy to apply to this flow.
1083  *
1084  * Returns 0 if policy found, else an -errno.
1085  */
1086 static int xfrm_policy_match(const struct xfrm_policy *pol,
1087                              const struct flowi *fl,
1088                              u8 type, u16 family, int dir)
1089 {
1090         const struct xfrm_selector *sel = &pol->selector;
1091         int ret = -ESRCH;
1092         bool match;
1093
1094         if (pol->family != family ||
1095             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1096             pol->type != type)
1097                 return ret;
1098
1099         match = xfrm_selector_match(sel, fl, family);
1100         if (match)
1101                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1102                                                   dir);
1103
1104         return ret;
1105 }
1106
1107 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1108                                                      const struct flowi *fl,
1109                                                      u16 family, u8 dir)
1110 {
1111         int err;
1112         struct xfrm_policy *pol, *ret;
1113         const xfrm_address_t *daddr, *saddr;
1114         struct hlist_head *chain;
1115         unsigned int sequence;
1116         u32 priority;
1117
1118         daddr = xfrm_flowi_daddr(fl, family);
1119         saddr = xfrm_flowi_saddr(fl, family);
1120         if (unlikely(!daddr || !saddr))
1121                 return NULL;
1122
1123         rcu_read_lock();
1124  retry:
1125         do {
1126                 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1127                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1128         } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1129
1130         priority = ~0U;
1131         ret = NULL;
1132         hlist_for_each_entry_rcu(pol, chain, bydst) {
1133                 err = xfrm_policy_match(pol, fl, type, family, dir);
1134                 if (err) {
1135                         if (err == -ESRCH)
1136                                 continue;
1137                         else {
1138                                 ret = ERR_PTR(err);
1139                                 goto fail;
1140                         }
1141                 } else {
1142                         ret = pol;
1143                         priority = ret->priority;
1144                         break;
1145                 }
1146         }
1147         chain = &net->xfrm.policy_inexact[dir];
1148         hlist_for_each_entry_rcu(pol, chain, bydst) {
1149                 if ((pol->priority >= priority) && ret)
1150                         break;
1151
1152                 err = xfrm_policy_match(pol, fl, type, family, dir);
1153                 if (err) {
1154                         if (err == -ESRCH)
1155                                 continue;
1156                         else {
1157                                 ret = ERR_PTR(err);
1158                                 goto fail;
1159                         }
1160                 } else {
1161                         ret = pol;
1162                         break;
1163                 }
1164         }
1165
1166         if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1167                 goto retry;
1168
1169         if (ret && !xfrm_pol_hold_rcu(ret))
1170                 goto retry;
1171 fail:
1172         rcu_read_unlock();
1173
1174         return ret;
1175 }
1176
1177 static struct xfrm_policy *
1178 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1179 {
1180 #ifdef CONFIG_XFRM_SUB_POLICY
1181         struct xfrm_policy *pol;
1182
1183         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1184         if (pol != NULL)
1185                 return pol;
1186 #endif
1187         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1188 }
1189
1190 static int flow_to_policy_dir(int dir)
1191 {
1192         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1193             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1194             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1195                 return dir;
1196
1197         switch (dir) {
1198         default:
1199         case FLOW_DIR_IN:
1200                 return XFRM_POLICY_IN;
1201         case FLOW_DIR_OUT:
1202                 return XFRM_POLICY_OUT;
1203         case FLOW_DIR_FWD:
1204                 return XFRM_POLICY_FWD;
1205         }
1206 }
1207
1208 static struct flow_cache_object *
1209 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1210                    u8 dir, struct flow_cache_object *old_obj, void *ctx)
1211 {
1212         struct xfrm_policy *pol;
1213
1214         if (old_obj)
1215                 xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1216
1217         pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
1218         if (IS_ERR_OR_NULL(pol))
1219                 return ERR_CAST(pol);
1220
1221         /* Resolver returns two references:
1222          * one for cache and one for caller of flow_cache_lookup() */
1223         xfrm_pol_hold(pol);
1224
1225         return &pol->flo;
1226 }
1227
1228 static inline int policy_to_flow_dir(int dir)
1229 {
1230         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1231             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1232             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1233                 return dir;
1234         switch (dir) {
1235         default:
1236         case XFRM_POLICY_IN:
1237                 return FLOW_DIR_IN;
1238         case XFRM_POLICY_OUT:
1239                 return FLOW_DIR_OUT;
1240         case XFRM_POLICY_FWD:
1241                 return FLOW_DIR_FWD;
1242         }
1243 }
1244
1245 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1246                                                  const struct flowi *fl, u16 family)
1247 {
1248         struct xfrm_policy *pol;
1249
1250         rcu_read_lock();
1251  again:
1252         pol = rcu_dereference(sk->sk_policy[dir]);
1253         if (pol != NULL) {
1254                 bool match = xfrm_selector_match(&pol->selector, fl, family);
1255                 int err = 0;
1256
1257                 if (match) {
1258                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1259                                 pol = NULL;
1260                                 goto out;
1261                         }
1262                         err = security_xfrm_policy_lookup(pol->security,
1263                                                       fl->flowi_secid,
1264                                                       policy_to_flow_dir(dir));
1265                         if (!err) {
1266                                 if (!xfrm_pol_hold_rcu(pol))
1267                                         goto again;
1268                         } else if (err == -ESRCH) {
1269                                 pol = NULL;
1270                         } else {
1271                                 pol = ERR_PTR(err);
1272                         }
1273                 } else
1274                         pol = NULL;
1275         }
1276 out:
1277         rcu_read_unlock();
1278         return pol;
1279 }
1280
1281 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1282 {
1283         struct net *net = xp_net(pol);
1284
1285         list_add(&pol->walk.all, &net->xfrm.policy_all);
1286         net->xfrm.policy_count[dir]++;
1287         xfrm_pol_hold(pol);
1288 }
1289
1290 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1291                                                 int dir)
1292 {
1293         struct net *net = xp_net(pol);
1294
1295         if (list_empty(&pol->walk.all))
1296                 return NULL;
1297
1298         /* Socket policies are not hashed. */
1299         if (!hlist_unhashed(&pol->bydst)) {
1300                 hlist_del_rcu(&pol->bydst);
1301                 hlist_del(&pol->byidx);
1302         }
1303
1304         list_del_init(&pol->walk.all);
1305         net->xfrm.policy_count[dir]--;
1306
1307         return pol;
1308 }
1309
1310 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1311 {
1312         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1313 }
1314
1315 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1316 {
1317         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1318 }
1319
1320 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1321 {
1322         struct net *net = xp_net(pol);
1323
1324         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1325         pol = __xfrm_policy_unlink(pol, dir);
1326         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1327         if (pol) {
1328                 xfrm_policy_kill(pol);
1329                 return 0;
1330         }
1331         return -ENOENT;
1332 }
1333 EXPORT_SYMBOL(xfrm_policy_delete);
1334
1335 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1336 {
1337         struct net *net = xp_net(pol);
1338         struct xfrm_policy *old_pol;
1339
1340 #ifdef CONFIG_XFRM_SUB_POLICY
1341         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1342                 return -EINVAL;
1343 #endif
1344
1345         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1346         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1347                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1348         if (pol) {
1349                 pol->curlft.add_time = get_seconds();
1350                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1351                 xfrm_sk_policy_link(pol, dir);
1352         }
1353         rcu_assign_pointer(sk->sk_policy[dir], pol);
1354         if (old_pol) {
1355                 if (pol)
1356                         xfrm_policy_requeue(old_pol, pol);
1357
1358                 /* Unlinking succeeds always. This is the only function
1359                  * allowed to delete or replace socket policy.
1360                  */
1361                 xfrm_sk_policy_unlink(old_pol, dir);
1362         }
1363         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1364
1365         if (old_pol) {
1366                 xfrm_policy_kill(old_pol);
1367         }
1368         return 0;
1369 }
1370
1371 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1372 {
1373         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1374         struct net *net = xp_net(old);
1375
1376         if (newp) {
1377                 newp->selector = old->selector;
1378                 if (security_xfrm_policy_clone(old->security,
1379                                                &newp->security)) {
1380                         kfree(newp);
1381                         return NULL;  /* ENOMEM */
1382                 }
1383                 newp->lft = old->lft;
1384                 newp->curlft = old->curlft;
1385                 newp->mark = old->mark;
1386                 newp->action = old->action;
1387                 newp->flags = old->flags;
1388                 newp->xfrm_nr = old->xfrm_nr;
1389                 newp->index = old->index;
1390                 newp->type = old->type;
1391                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1392                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1393                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1394                 xfrm_sk_policy_link(newp, dir);
1395                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1396                 xfrm_pol_put(newp);
1397         }
1398         return newp;
1399 }
1400
1401 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1402 {
1403         const struct xfrm_policy *p;
1404         struct xfrm_policy *np;
1405         int i, ret = 0;
1406
1407         rcu_read_lock();
1408         for (i = 0; i < 2; i++) {
1409                 p = rcu_dereference(osk->sk_policy[i]);
1410                 if (p) {
1411                         np = clone_policy(p, i);
1412                         if (unlikely(!np)) {
1413                                 ret = -ENOMEM;
1414                                 break;
1415                         }
1416                         rcu_assign_pointer(sk->sk_policy[i], np);
1417                 }
1418         }
1419         rcu_read_unlock();
1420         return ret;
1421 }
1422
1423 static int
1424 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1425                xfrm_address_t *remote, unsigned short family)
1426 {
1427         int err;
1428         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1429
1430         if (unlikely(afinfo == NULL))
1431                 return -EINVAL;
1432         err = afinfo->get_saddr(net, oif, local, remote);
1433         rcu_read_unlock();
1434         return err;
1435 }
1436
1437 /* Resolve list of templates for the flow, given policy. */
1438
1439 static int
1440 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1441                       struct xfrm_state **xfrm, unsigned short family)
1442 {
1443         struct net *net = xp_net(policy);
1444         int nx;
1445         int i, error;
1446         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1447         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1448         xfrm_address_t tmp;
1449
1450         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1451                 struct xfrm_state *x;
1452                 xfrm_address_t *remote = daddr;
1453                 xfrm_address_t *local  = saddr;
1454                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1455
1456                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1457                     tmpl->mode == XFRM_MODE_BEET) {
1458                         remote = &tmpl->id.daddr;
1459                         local = &tmpl->saddr;
1460                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1461                                 error = xfrm_get_saddr(net, fl->flowi_oif,
1462                                                        &tmp, remote,
1463                                                        tmpl->encap_family);
1464                                 if (error)
1465                                         goto fail;
1466                                 local = &tmp;
1467                         }
1468                 }
1469
1470                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1471
1472                 if (x && x->km.state == XFRM_STATE_VALID) {
1473                         xfrm[nx++] = x;
1474                         daddr = remote;
1475                         saddr = local;
1476                         continue;
1477                 }
1478                 if (x) {
1479                         error = (x->km.state == XFRM_STATE_ERROR ?
1480                                  -EINVAL : -EAGAIN);
1481                         xfrm_state_put(x);
1482                 } else if (error == -ESRCH) {
1483                         error = -EAGAIN;
1484                 }
1485
1486                 if (!tmpl->optional)
1487                         goto fail;
1488         }
1489         return nx;
1490
1491 fail:
1492         for (nx--; nx >= 0; nx--)
1493                 xfrm_state_put(xfrm[nx]);
1494         return error;
1495 }
1496
1497 static int
1498 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1499                   struct xfrm_state **xfrm, unsigned short family)
1500 {
1501         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1502         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1503         int cnx = 0;
1504         int error;
1505         int ret;
1506         int i;
1507
1508         for (i = 0; i < npols; i++) {
1509                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1510                         error = -ENOBUFS;
1511                         goto fail;
1512                 }
1513
1514                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1515                 if (ret < 0) {
1516                         error = ret;
1517                         goto fail;
1518                 } else
1519                         cnx += ret;
1520         }
1521
1522         /* found states are sorted for outbound processing */
1523         if (npols > 1)
1524                 xfrm_state_sort(xfrm, tpp, cnx, family);
1525
1526         return cnx;
1527
1528  fail:
1529         for (cnx--; cnx >= 0; cnx--)
1530                 xfrm_state_put(tpp[cnx]);
1531         return error;
1532
1533 }
1534
1535 static int xfrm_get_tos(const struct flowi *fl, int family)
1536 {
1537         const struct xfrm_policy_afinfo *afinfo;
1538         int tos = 0;
1539
1540         afinfo = xfrm_policy_get_afinfo(family);
1541         tos = afinfo ? afinfo->get_tos(fl) : 0;
1542
1543         rcu_read_unlock();
1544
1545         return tos;
1546 }
1547
1548 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1549 {
1550         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1551         struct dst_entry *dst = &xdst->u.dst;
1552
1553         if (xdst->route == NULL) {
1554                 /* Dummy bundle - if it has xfrms we were not
1555                  * able to build bundle as template resolution failed.
1556                  * It means we need to try again resolving. */
1557                 if (xdst->num_xfrms > 0)
1558                         return NULL;
1559         } else if (dst->flags & DST_XFRM_QUEUE) {
1560                 return NULL;
1561         } else {
1562                 /* Real bundle */
1563                 if (stale_bundle(dst))
1564                         return NULL;
1565         }
1566
1567         dst_hold(dst);
1568         return flo;
1569 }
1570
1571 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1572 {
1573         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1574         struct dst_entry *dst = &xdst->u.dst;
1575
1576         if (!xdst->route)
1577                 return 0;
1578         if (stale_bundle(dst))
1579                 return 0;
1580
1581         return 1;
1582 }
1583
1584 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1585 {
1586         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1587         struct dst_entry *dst = &xdst->u.dst;
1588
1589         dst_free(dst);
1590 }
1591
1592 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1593         .get = xfrm_bundle_flo_get,
1594         .check = xfrm_bundle_flo_check,
1595         .delete = xfrm_bundle_flo_delete,
1596 };
1597
1598 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1599 {
1600         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1601         struct dst_ops *dst_ops;
1602         struct xfrm_dst *xdst;
1603
1604         if (!afinfo)
1605                 return ERR_PTR(-EINVAL);
1606
1607         switch (family) {
1608         case AF_INET:
1609                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1610                 break;
1611 #if IS_ENABLED(CONFIG_IPV6)
1612         case AF_INET6:
1613                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1614                 break;
1615 #endif
1616         default:
1617                 BUG();
1618         }
1619         xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1620
1621         if (likely(xdst)) {
1622                 struct dst_entry *dst = &xdst->u.dst;
1623
1624                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1625                 xdst->flo.ops = &xfrm_bundle_fc_ops;
1626         } else
1627                 xdst = ERR_PTR(-ENOBUFS);
1628
1629         rcu_read_unlock();
1630
1631         return xdst;
1632 }
1633
1634 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1635                                  int nfheader_len)
1636 {
1637         const struct xfrm_policy_afinfo *afinfo =
1638                 xfrm_policy_get_afinfo(dst->ops->family);
1639         int err;
1640
1641         if (!afinfo)
1642                 return -EINVAL;
1643
1644         err = afinfo->init_path(path, dst, nfheader_len);
1645
1646         rcu_read_unlock();
1647
1648         return err;
1649 }
1650
1651 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1652                                 const struct flowi *fl)
1653 {
1654         const struct xfrm_policy_afinfo *afinfo =
1655                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1656         int err;
1657
1658         if (!afinfo)
1659                 return -EINVAL;
1660
1661         err = afinfo->fill_dst(xdst, dev, fl);
1662
1663         rcu_read_unlock();
1664
1665         return err;
1666 }
1667
1668
1669 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1670  * all the metrics... Shortly, bundle a bundle.
1671  */
1672
1673 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1674                                             struct xfrm_state **xfrm, int nx,
1675                                             const struct flowi *fl,
1676                                             struct dst_entry *dst)
1677 {
1678         struct net *net = xp_net(policy);
1679         unsigned long now = jiffies;
1680         struct net_device *dev;
1681         struct xfrm_mode *inner_mode;
1682         struct dst_entry *dst_prev = NULL;
1683         struct dst_entry *dst0 = NULL;
1684         int i = 0;
1685         int err;
1686         int header_len = 0;
1687         int nfheader_len = 0;
1688         int trailer_len = 0;
1689         int tos;
1690         int family = policy->selector.family;
1691         xfrm_address_t saddr, daddr;
1692
1693         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1694
1695         tos = xfrm_get_tos(fl, family);
1696
1697         dst_hold(dst);
1698
1699         for (; i < nx; i++) {
1700                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1701                 struct dst_entry *dst1 = &xdst->u.dst;
1702
1703                 err = PTR_ERR(xdst);
1704                 if (IS_ERR(xdst)) {
1705                         dst_release(dst);
1706                         goto put_states;
1707                 }
1708
1709                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1710                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1711                                                         xfrm_af2proto(family));
1712                         if (!inner_mode) {
1713                                 err = -EAFNOSUPPORT;
1714                                 dst_release(dst);
1715                                 goto put_states;
1716                         }
1717                 } else
1718                         inner_mode = xfrm[i]->inner_mode;
1719
1720                 if (!dst_prev)
1721                         dst0 = dst1;
1722                 else {
1723                         dst_prev->child = dst_clone(dst1);
1724                         dst1->flags |= DST_NOHASH;
1725                 }
1726
1727                 xdst->route = dst;
1728                 dst_copy_metrics(dst1, dst);
1729
1730                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1731                         family = xfrm[i]->props.family;
1732                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1733                                               &saddr, &daddr, family);
1734                         err = PTR_ERR(dst);
1735                         if (IS_ERR(dst))
1736                                 goto put_states;
1737                 } else
1738                         dst_hold(dst);
1739
1740                 dst1->xfrm = xfrm[i];
1741                 xdst->xfrm_genid = xfrm[i]->genid;
1742
1743                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1744                 dst1->flags |= DST_HOST;
1745                 dst1->lastuse = now;
1746
1747                 dst1->input = dst_discard;
1748                 dst1->output = inner_mode->afinfo->output;
1749
1750                 dst1->next = dst_prev;
1751                 dst_prev = dst1;
1752
1753                 header_len += xfrm[i]->props.header_len;
1754                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1755                         nfheader_len += xfrm[i]->props.header_len;
1756                 trailer_len += xfrm[i]->props.trailer_len;
1757         }
1758
1759         dst_prev->child = dst;
1760         dst0->path = dst;
1761
1762         err = -ENODEV;
1763         dev = dst->dev;
1764         if (!dev)
1765                 goto free_dst;
1766
1767         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1768         xfrm_init_pmtu(dst_prev);
1769
1770         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1771                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1772
1773                 err = xfrm_fill_dst(xdst, dev, fl);
1774                 if (err)
1775                         goto free_dst;
1776
1777                 dst_prev->header_len = header_len;
1778                 dst_prev->trailer_len = trailer_len;
1779                 header_len -= xdst->u.dst.xfrm->props.header_len;
1780                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1781         }
1782
1783 out:
1784         return dst0;
1785
1786 put_states:
1787         for (; i < nx; i++)
1788                 xfrm_state_put(xfrm[i]);
1789 free_dst:
1790         if (dst0)
1791                 dst_free(dst0);
1792         dst0 = ERR_PTR(err);
1793         goto out;
1794 }
1795
1796 #ifdef CONFIG_XFRM_SUB_POLICY
1797 static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
1798 {
1799         if (!*target) {
1800                 *target = kmalloc(size, GFP_ATOMIC);
1801                 if (!*target)
1802                         return -ENOMEM;
1803         }
1804
1805         memcpy(*target, src, size);
1806         return 0;
1807 }
1808 #endif
1809
1810 static int xfrm_dst_update_parent(struct dst_entry *dst,
1811                                   const struct xfrm_selector *sel)
1812 {
1813 #ifdef CONFIG_XFRM_SUB_POLICY
1814         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1815         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1816                                    sel, sizeof(*sel));
1817 #else
1818         return 0;
1819 #endif
1820 }
1821
1822 static int xfrm_dst_update_origin(struct dst_entry *dst,
1823                                   const struct flowi *fl)
1824 {
1825 #ifdef CONFIG_XFRM_SUB_POLICY
1826         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1827         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1828 #else
1829         return 0;
1830 #endif
1831 }
1832
1833 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1834                                 struct xfrm_policy **pols,
1835                                 int *num_pols, int *num_xfrms)
1836 {
1837         int i;
1838
1839         if (*num_pols == 0 || !pols[0]) {
1840                 *num_pols = 0;
1841                 *num_xfrms = 0;
1842                 return 0;
1843         }
1844         if (IS_ERR(pols[0]))
1845                 return PTR_ERR(pols[0]);
1846
1847         *num_xfrms = pols[0]->xfrm_nr;
1848
1849 #ifdef CONFIG_XFRM_SUB_POLICY
1850         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1851             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1852                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1853                                                     XFRM_POLICY_TYPE_MAIN,
1854                                                     fl, family,
1855                                                     XFRM_POLICY_OUT);
1856                 if (pols[1]) {
1857                         if (IS_ERR(pols[1])) {
1858                                 xfrm_pols_put(pols, *num_pols);
1859                                 return PTR_ERR(pols[1]);
1860                         }
1861                         (*num_pols)++;
1862                         (*num_xfrms) += pols[1]->xfrm_nr;
1863                 }
1864         }
1865 #endif
1866         for (i = 0; i < *num_pols; i++) {
1867                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1868                         *num_xfrms = -1;
1869                         break;
1870                 }
1871         }
1872
1873         return 0;
1874
1875 }
1876
1877 static struct xfrm_dst *
1878 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1879                                const struct flowi *fl, u16 family,
1880                                struct dst_entry *dst_orig)
1881 {
1882         struct net *net = xp_net(pols[0]);
1883         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1884         struct dst_entry *dst;
1885         struct xfrm_dst *xdst;
1886         int err;
1887
1888         /* Try to instantiate a bundle */
1889         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1890         if (err <= 0) {
1891                 if (err != 0 && err != -EAGAIN)
1892                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1893                 return ERR_PTR(err);
1894         }
1895
1896         dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1897         if (IS_ERR(dst)) {
1898                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1899                 return ERR_CAST(dst);
1900         }
1901
1902         xdst = (struct xfrm_dst *)dst;
1903         xdst->num_xfrms = err;
1904         if (num_pols > 1)
1905                 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1906         else
1907                 err = xfrm_dst_update_origin(dst, fl);
1908         if (unlikely(err)) {
1909                 dst_free(dst);
1910                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1911                 return ERR_PTR(err);
1912         }
1913
1914         xdst->num_pols = num_pols;
1915         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1916         xdst->policy_genid = atomic_read(&pols[0]->genid);
1917
1918         return xdst;
1919 }
1920
1921 static void xfrm_policy_queue_process(unsigned long arg)
1922 {
1923         struct sk_buff *skb;
1924         struct sock *sk;
1925         struct dst_entry *dst;
1926         struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1927         struct net *net = xp_net(pol);
1928         struct xfrm_policy_queue *pq = &pol->polq;
1929         struct flowi fl;
1930         struct sk_buff_head list;
1931
1932         spin_lock(&pq->hold_queue.lock);
1933         skb = skb_peek(&pq->hold_queue);
1934         if (!skb) {
1935                 spin_unlock(&pq->hold_queue.lock);
1936                 goto out;
1937         }
1938         dst = skb_dst(skb);
1939         sk = skb->sk;
1940         xfrm_decode_session(skb, &fl, dst->ops->family);
1941         spin_unlock(&pq->hold_queue.lock);
1942
1943         dst_hold(dst->path);
1944         dst = xfrm_lookup(net, dst->path, &fl, sk, 0);
1945         if (IS_ERR(dst))
1946                 goto purge_queue;
1947
1948         if (dst->flags & DST_XFRM_QUEUE) {
1949                 dst_release(dst);
1950
1951                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1952                         goto purge_queue;
1953
1954                 pq->timeout = pq->timeout << 1;
1955                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1956                         xfrm_pol_hold(pol);
1957         goto out;
1958         }
1959
1960         dst_release(dst);
1961
1962         __skb_queue_head_init(&list);
1963
1964         spin_lock(&pq->hold_queue.lock);
1965         pq->timeout = 0;
1966         skb_queue_splice_init(&pq->hold_queue, &list);
1967         spin_unlock(&pq->hold_queue.lock);
1968
1969         while (!skb_queue_empty(&list)) {
1970                 skb = __skb_dequeue(&list);
1971
1972                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1973                 dst_hold(skb_dst(skb)->path);
1974                 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0);
1975                 if (IS_ERR(dst)) {
1976                         kfree_skb(skb);
1977                         continue;
1978                 }
1979
1980                 nf_reset(skb);
1981                 skb_dst_drop(skb);
1982                 skb_dst_set(skb, dst);
1983
1984                 dst_output(net, skb->sk, skb);
1985         }
1986
1987 out:
1988         xfrm_pol_put(pol);
1989         return;
1990
1991 purge_queue:
1992         pq->timeout = 0;
1993         skb_queue_purge(&pq->hold_queue);
1994         xfrm_pol_put(pol);
1995 }
1996
1997 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1998 {
1999         unsigned long sched_next;
2000         struct dst_entry *dst = skb_dst(skb);
2001         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2002         struct xfrm_policy *pol = xdst->pols[0];
2003         struct xfrm_policy_queue *pq = &pol->polq;
2004
2005         if (unlikely(skb_fclone_busy(sk, skb))) {
2006                 kfree_skb(skb);
2007                 return 0;
2008         }
2009
2010         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2011                 kfree_skb(skb);
2012                 return -EAGAIN;
2013         }
2014
2015         skb_dst_force(skb);
2016
2017         spin_lock_bh(&pq->hold_queue.lock);
2018
2019         if (!pq->timeout)
2020                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2021
2022         sched_next = jiffies + pq->timeout;
2023
2024         if (del_timer(&pq->hold_timer)) {
2025                 if (time_before(pq->hold_timer.expires, sched_next))
2026                         sched_next = pq->hold_timer.expires;
2027                 xfrm_pol_put(pol);
2028         }
2029
2030         __skb_queue_tail(&pq->hold_queue, skb);
2031         if (!mod_timer(&pq->hold_timer, sched_next))
2032                 xfrm_pol_hold(pol);
2033
2034         spin_unlock_bh(&pq->hold_queue.lock);
2035
2036         return 0;
2037 }
2038
2039 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2040                                                  struct xfrm_flo *xflo,
2041                                                  const struct flowi *fl,
2042                                                  int num_xfrms,
2043                                                  u16 family)
2044 {
2045         int err;
2046         struct net_device *dev;
2047         struct dst_entry *dst;
2048         struct dst_entry *dst1;
2049         struct xfrm_dst *xdst;
2050
2051         xdst = xfrm_alloc_dst(net, family);
2052         if (IS_ERR(xdst))
2053                 return xdst;
2054
2055         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2056             net->xfrm.sysctl_larval_drop ||
2057             num_xfrms <= 0)
2058                 return xdst;
2059
2060         dst = xflo->dst_orig;
2061         dst1 = &xdst->u.dst;
2062         dst_hold(dst);
2063         xdst->route = dst;
2064
2065         dst_copy_metrics(dst1, dst);
2066
2067         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2068         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2069         dst1->lastuse = jiffies;
2070
2071         dst1->input = dst_discard;
2072         dst1->output = xdst_queue_output;
2073
2074         dst_hold(dst);
2075         dst1->child = dst;
2076         dst1->path = dst;
2077
2078         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2079
2080         err = -ENODEV;
2081         dev = dst->dev;
2082         if (!dev)
2083                 goto free_dst;
2084
2085         err = xfrm_fill_dst(xdst, dev, fl);
2086         if (err)
2087                 goto free_dst;
2088
2089 out:
2090         return xdst;
2091
2092 free_dst:
2093         dst_release(dst1);
2094         xdst = ERR_PTR(err);
2095         goto out;
2096 }
2097
2098 static struct flow_cache_object *
2099 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
2100                    struct flow_cache_object *oldflo, void *ctx)
2101 {
2102         struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
2103         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2104         struct xfrm_dst *xdst, *new_xdst;
2105         int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
2106
2107         /* Check if the policies from old bundle are usable */
2108         xdst = NULL;
2109         if (oldflo) {
2110                 xdst = container_of(oldflo, struct xfrm_dst, flo);
2111                 num_pols = xdst->num_pols;
2112                 num_xfrms = xdst->num_xfrms;
2113                 pol_dead = 0;
2114                 for (i = 0; i < num_pols; i++) {
2115                         pols[i] = xdst->pols[i];
2116                         pol_dead |= pols[i]->walk.dead;
2117                 }
2118                 if (pol_dead) {
2119                         dst_free(&xdst->u.dst);
2120                         xdst = NULL;
2121                         num_pols = 0;
2122                         num_xfrms = 0;
2123                         oldflo = NULL;
2124                 }
2125         }
2126
2127         /* Resolve policies to use if we couldn't get them from
2128          * previous cache entry */
2129         if (xdst == NULL) {
2130                 num_pols = 1;
2131                 pols[0] = __xfrm_policy_lookup(net, fl, family,
2132                                                flow_to_policy_dir(dir));
2133                 err = xfrm_expand_policies(fl, family, pols,
2134                                            &num_pols, &num_xfrms);
2135                 if (err < 0)
2136                         goto inc_error;
2137                 if (num_pols == 0)
2138                         return NULL;
2139                 if (num_xfrms <= 0)
2140                         goto make_dummy_bundle;
2141         }
2142
2143         new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2144                                                   xflo->dst_orig);
2145         if (IS_ERR(new_xdst)) {
2146                 err = PTR_ERR(new_xdst);
2147                 if (err != -EAGAIN)
2148                         goto error;
2149                 if (oldflo == NULL)
2150                         goto make_dummy_bundle;
2151                 dst_hold(&xdst->u.dst);
2152                 return oldflo;
2153         } else if (new_xdst == NULL) {
2154                 num_xfrms = 0;
2155                 if (oldflo == NULL)
2156                         goto make_dummy_bundle;
2157                 xdst->num_xfrms = 0;
2158                 dst_hold(&xdst->u.dst);
2159                 return oldflo;
2160         }
2161
2162         /* Kill the previous bundle */
2163         if (xdst) {
2164                 /* The policies were stolen for newly generated bundle */
2165                 xdst->num_pols = 0;
2166                 dst_free(&xdst->u.dst);
2167         }
2168
2169         /* Flow cache does not have reference, it dst_free()'s,
2170          * but we do need to return one reference for original caller */
2171         dst_hold(&new_xdst->u.dst);
2172         return &new_xdst->flo;
2173
2174 make_dummy_bundle:
2175         /* We found policies, but there's no bundles to instantiate:
2176          * either because the policy blocks, has no transformations or
2177          * we could not build template (no xfrm_states).*/
2178         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2179         if (IS_ERR(xdst)) {
2180                 xfrm_pols_put(pols, num_pols);
2181                 return ERR_CAST(xdst);
2182         }
2183         xdst->num_pols = num_pols;
2184         xdst->num_xfrms = num_xfrms;
2185         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2186
2187         dst_hold(&xdst->u.dst);
2188         return &xdst->flo;
2189
2190 inc_error:
2191         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2192 error:
2193         if (xdst != NULL)
2194                 dst_free(&xdst->u.dst);
2195         else
2196                 xfrm_pols_put(pols, num_pols);
2197         return ERR_PTR(err);
2198 }
2199
2200 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2201                                         struct dst_entry *dst_orig)
2202 {
2203         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2204         struct dst_entry *ret;
2205
2206         if (!afinfo) {
2207                 dst_release(dst_orig);
2208                 return ERR_PTR(-EINVAL);
2209         } else {
2210                 ret = afinfo->blackhole_route(net, dst_orig);
2211         }
2212         rcu_read_unlock();
2213
2214         return ret;
2215 }
2216
2217 /* Main function: finds/creates a bundle for given flow.
2218  *
2219  * At the moment we eat a raw IP route. Mostly to speed up lookups
2220  * on interfaces with disabled IPsec.
2221  */
2222 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2223                               const struct flowi *fl,
2224                               const struct sock *sk, int flags)
2225 {
2226         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2227         struct flow_cache_object *flo;
2228         struct xfrm_dst *xdst;
2229         struct dst_entry *dst, *route;
2230         u16 family = dst_orig->ops->family;
2231         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2232         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2233
2234         dst = NULL;
2235         xdst = NULL;
2236         route = NULL;
2237
2238         sk = sk_const_to_full_sk(sk);
2239         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2240                 num_pols = 1;
2241                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family);
2242                 err = xfrm_expand_policies(fl, family, pols,
2243                                            &num_pols, &num_xfrms);
2244                 if (err < 0)
2245                         goto dropdst;
2246
2247                 if (num_pols) {
2248                         if (num_xfrms <= 0) {
2249                                 drop_pols = num_pols;
2250                                 goto no_transform;
2251                         }
2252
2253                         xdst = xfrm_resolve_and_create_bundle(
2254                                         pols, num_pols, fl,
2255                                         family, dst_orig);
2256                         if (IS_ERR(xdst)) {
2257                                 xfrm_pols_put(pols, num_pols);
2258                                 err = PTR_ERR(xdst);
2259                                 goto dropdst;
2260                         } else if (xdst == NULL) {
2261                                 num_xfrms = 0;
2262                                 drop_pols = num_pols;
2263                                 goto no_transform;
2264                         }
2265
2266                         dst_hold(&xdst->u.dst);
2267                         xdst->u.dst.flags |= DST_NOCACHE;
2268                         route = xdst->route;
2269                 }
2270         }
2271
2272         if (xdst == NULL) {
2273                 struct xfrm_flo xflo;
2274
2275                 xflo.dst_orig = dst_orig;
2276                 xflo.flags = flags;
2277
2278                 /* To accelerate a bit...  */
2279                 if ((dst_orig->flags & DST_NOXFRM) ||
2280                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2281                         goto nopol;
2282
2283                 flo = flow_cache_lookup(net, fl, family, dir,
2284                                         xfrm_bundle_lookup, &xflo);
2285                 if (flo == NULL)
2286                         goto nopol;
2287                 if (IS_ERR(flo)) {
2288                         err = PTR_ERR(flo);
2289                         goto dropdst;
2290                 }
2291                 xdst = container_of(flo, struct xfrm_dst, flo);
2292
2293                 num_pols = xdst->num_pols;
2294                 num_xfrms = xdst->num_xfrms;
2295                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2296                 route = xdst->route;
2297         }
2298
2299         dst = &xdst->u.dst;
2300         if (route == NULL && num_xfrms > 0) {
2301                 /* The only case when xfrm_bundle_lookup() returns a
2302                  * bundle with null route, is when the template could
2303                  * not be resolved. It means policies are there, but
2304                  * bundle could not be created, since we don't yet
2305                  * have the xfrm_state's. We need to wait for KM to
2306                  * negotiate new SA's or bail out with error.*/
2307                 if (net->xfrm.sysctl_larval_drop) {
2308                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2309                         err = -EREMOTE;
2310                         goto error;
2311                 }
2312
2313                 err = -EAGAIN;
2314
2315                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2316                 goto error;
2317         }
2318
2319 no_transform:
2320         if (num_pols == 0)
2321                 goto nopol;
2322
2323         if ((flags & XFRM_LOOKUP_ICMP) &&
2324             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2325                 err = -ENOENT;
2326                 goto error;
2327         }
2328
2329         for (i = 0; i < num_pols; i++)
2330                 pols[i]->curlft.use_time = get_seconds();
2331
2332         if (num_xfrms < 0) {
2333                 /* Prohibit the flow */
2334                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2335                 err = -EPERM;
2336                 goto error;
2337         } else if (num_xfrms > 0) {
2338                 /* Flow transformed */
2339                 dst_release(dst_orig);
2340         } else {
2341                 /* Flow passes untransformed */
2342                 dst_release(dst);
2343                 dst = dst_orig;
2344         }
2345 ok:
2346         xfrm_pols_put(pols, drop_pols);
2347         if (dst && dst->xfrm &&
2348             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2349                 dst->flags |= DST_XFRM_TUNNEL;
2350         return dst;
2351
2352 nopol:
2353         if (!(flags & XFRM_LOOKUP_ICMP)) {
2354                 dst = dst_orig;
2355                 goto ok;
2356         }
2357         err = -ENOENT;
2358 error:
2359         dst_release(dst);
2360 dropdst:
2361         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2362                 dst_release(dst_orig);
2363         xfrm_pols_put(pols, drop_pols);
2364         return ERR_PTR(err);
2365 }
2366 EXPORT_SYMBOL(xfrm_lookup);
2367
2368 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2369  * Otherwise we may send out blackholed packets.
2370  */
2371 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2372                                     const struct flowi *fl,
2373                                     const struct sock *sk, int flags)
2374 {
2375         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2376                                             flags | XFRM_LOOKUP_QUEUE |
2377                                             XFRM_LOOKUP_KEEP_DST_REF);
2378
2379         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2380                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2381
2382         return dst;
2383 }
2384 EXPORT_SYMBOL(xfrm_lookup_route);
2385
2386 static inline int
2387 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2388 {
2389         struct xfrm_state *x;
2390
2391         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2392                 return 0;
2393         x = skb->sp->xvec[idx];
2394         if (!x->type->reject)
2395                 return 0;
2396         return x->type->reject(x, skb, fl);
2397 }
2398
2399 /* When skb is transformed back to its "native" form, we have to
2400  * check policy restrictions. At the moment we make this in maximally
2401  * stupid way. Shame on me. :-) Of course, connected sockets must
2402  * have policy cached at them.
2403  */
2404
2405 static inline int
2406 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2407               unsigned short family)
2408 {
2409         if (xfrm_state_kern(x))
2410                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2411         return  x->id.proto == tmpl->id.proto &&
2412                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2413                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2414                 x->props.mode == tmpl->mode &&
2415                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2416                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2417                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2418                   xfrm_state_addr_cmp(tmpl, x, family));
2419 }
2420
2421 /*
2422  * 0 or more than 0 is returned when validation is succeeded (either bypass
2423  * because of optional transport mode, or next index of the mathced secpath
2424  * state with the template.
2425  * -1 is returned when no matching template is found.
2426  * Otherwise "-2 - errored_index" is returned.
2427  */
2428 static inline int
2429 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2430                unsigned short family)
2431 {
2432         int idx = start;
2433
2434         if (tmpl->optional) {
2435                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2436                         return start;
2437         } else
2438                 start = -1;
2439         for (; idx < sp->len; idx++) {
2440                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2441                         return ++idx;
2442                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2443                         if (start == -1)
2444                                 start = -2-idx;
2445                         break;
2446                 }
2447         }
2448         return start;
2449 }
2450
2451 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2452                           unsigned int family, int reverse)
2453 {
2454         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2455         int err;
2456
2457         if (unlikely(afinfo == NULL))
2458                 return -EAFNOSUPPORT;
2459
2460         afinfo->decode_session(skb, fl, reverse);
2461         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2462         rcu_read_unlock();
2463         return err;
2464 }
2465 EXPORT_SYMBOL(__xfrm_decode_session);
2466
2467 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2468 {
2469         for (; k < sp->len; k++) {
2470                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2471                         *idxp = k;
2472                         return 1;
2473                 }
2474         }
2475
2476         return 0;
2477 }
2478
2479 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2480                         unsigned short family)
2481 {
2482         struct net *net = dev_net(skb->dev);
2483         struct xfrm_policy *pol;
2484         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2485         int npols = 0;
2486         int xfrm_nr;
2487         int pi;
2488         int reverse;
2489         struct flowi fl;
2490         u8 fl_dir;
2491         int xerr_idx = -1;
2492
2493         reverse = dir & ~XFRM_POLICY_MASK;
2494         dir &= XFRM_POLICY_MASK;
2495         fl_dir = policy_to_flow_dir(dir);
2496
2497         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2498                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2499                 return 0;
2500         }
2501
2502         nf_nat_decode_session(skb, &fl, family);
2503
2504         /* First, check used SA against their selectors. */
2505         if (skb->sp) {
2506                 int i;
2507
2508                 for (i = skb->sp->len-1; i >= 0; i--) {
2509                         struct xfrm_state *x = skb->sp->xvec[i];
2510                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2511                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2512                                 return 0;
2513                         }
2514                 }
2515         }
2516
2517         pol = NULL;
2518         sk = sk_to_full_sk(sk);
2519         if (sk && sk->sk_policy[dir]) {
2520                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family);
2521                 if (IS_ERR(pol)) {
2522                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2523                         return 0;
2524                 }
2525         }
2526
2527         if (!pol) {
2528                 struct flow_cache_object *flo;
2529
2530                 flo = flow_cache_lookup(net, &fl, family, fl_dir,
2531                                         xfrm_policy_lookup, NULL);
2532                 if (IS_ERR_OR_NULL(flo))
2533                         pol = ERR_CAST(flo);
2534                 else
2535                         pol = container_of(flo, struct xfrm_policy, flo);
2536         }
2537
2538         if (IS_ERR(pol)) {
2539                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2540                 return 0;
2541         }
2542
2543         if (!pol) {
2544                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2545                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2546                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2547                         return 0;
2548                 }
2549                 return 1;
2550         }
2551
2552         pol->curlft.use_time = get_seconds();
2553
2554         pols[0] = pol;
2555         npols++;
2556 #ifdef CONFIG_XFRM_SUB_POLICY
2557         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2558                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2559                                                     &fl, family,
2560                                                     XFRM_POLICY_IN);
2561                 if (pols[1]) {
2562                         if (IS_ERR(pols[1])) {
2563                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2564                                 return 0;
2565                         }
2566                         pols[1]->curlft.use_time = get_seconds();
2567                         npols++;
2568                 }
2569         }
2570 #endif
2571
2572         if (pol->action == XFRM_POLICY_ALLOW) {
2573                 struct sec_path *sp;
2574                 static struct sec_path dummy;
2575                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2576                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2577                 struct xfrm_tmpl **tpp = tp;
2578                 int ti = 0;
2579                 int i, k;
2580
2581                 if ((sp = skb->sp) == NULL)
2582                         sp = &dummy;
2583
2584                 for (pi = 0; pi < npols; pi++) {
2585                         if (pols[pi] != pol &&
2586                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2587                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2588                                 goto reject;
2589                         }
2590                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2591                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2592                                 goto reject_error;
2593                         }
2594                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2595                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2596                 }
2597                 xfrm_nr = ti;
2598                 if (npols > 1) {
2599                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2600                         tpp = stp;
2601                 }
2602
2603                 /* For each tunnel xfrm, find the first matching tmpl.
2604                  * For each tmpl before that, find corresponding xfrm.
2605                  * Order is _important_. Later we will implement
2606                  * some barriers, but at the moment barriers
2607                  * are implied between each two transformations.
2608                  */
2609                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2610                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2611                         if (k < 0) {
2612                                 if (k < -1)
2613                                         /* "-2 - errored_index" returned */
2614                                         xerr_idx = -(2+k);
2615                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2616                                 goto reject;
2617                         }
2618                 }
2619
2620                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2621                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2622                         goto reject;
2623                 }
2624
2625                 xfrm_pols_put(pols, npols);
2626                 return 1;
2627         }
2628         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2629
2630 reject:
2631         xfrm_secpath_reject(xerr_idx, skb, &fl);
2632 reject_error:
2633         xfrm_pols_put(pols, npols);
2634         return 0;
2635 }
2636 EXPORT_SYMBOL(__xfrm_policy_check);
2637
2638 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2639 {
2640         struct net *net = dev_net(skb->dev);
2641         struct flowi fl;
2642         struct dst_entry *dst;
2643         int res = 1;
2644
2645         if (xfrm_decode_session(skb, &fl, family) < 0) {
2646                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2647                 return 0;
2648         }
2649
2650         skb_dst_force(skb);
2651
2652         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2653         if (IS_ERR(dst)) {
2654                 res = 0;
2655                 dst = NULL;
2656         }
2657         skb_dst_set(skb, dst);
2658         return res;
2659 }
2660 EXPORT_SYMBOL(__xfrm_route_forward);
2661
2662 /* Optimize later using cookies and generation ids. */
2663
2664 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2665 {
2666         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2667          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2668          * get validated by dst_ops->check on every use.  We do this
2669          * because when a normal route referenced by an XFRM dst is
2670          * obsoleted we do not go looking around for all parent
2671          * referencing XFRM dsts so that we can invalidate them.  It
2672          * is just too much work.  Instead we make the checks here on
2673          * every use.  For example:
2674          *
2675          *      XFRM dst A --> IPv4 dst X
2676          *
2677          * X is the "xdst->route" of A (X is also the "dst->path" of A
2678          * in this example).  If X is marked obsolete, "A" will not
2679          * notice.  That's what we are validating here via the
2680          * stale_bundle() check.
2681          *
2682          * When a policy's bundle is pruned, we dst_free() the XFRM
2683          * dst which causes it's ->obsolete field to be set to
2684          * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2685          * this, we want to force a new route lookup.
2686          */
2687         if (dst->obsolete < 0 && !stale_bundle(dst))
2688                 return dst;
2689
2690         return NULL;
2691 }
2692
2693 static int stale_bundle(struct dst_entry *dst)
2694 {
2695         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2696 }
2697
2698 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2699 {
2700         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2701                 dst->dev = dev_net(dev)->loopback_dev;
2702                 dev_hold(dst->dev);
2703                 dev_put(dev);
2704         }
2705 }
2706 EXPORT_SYMBOL(xfrm_dst_ifdown);
2707
2708 static void xfrm_link_failure(struct sk_buff *skb)
2709 {
2710         /* Impossible. Such dst must be popped before reaches point of failure. */
2711 }
2712
2713 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2714 {
2715         if (dst) {
2716                 if (dst->obsolete) {
2717                         dst_release(dst);
2718                         dst = NULL;
2719                 }
2720         }
2721         return dst;
2722 }
2723
2724 void xfrm_garbage_collect(struct net *net)
2725 {
2726         flow_cache_flush(net);
2727 }
2728 EXPORT_SYMBOL(xfrm_garbage_collect);
2729
2730 void xfrm_garbage_collect_deferred(struct net *net)
2731 {
2732         flow_cache_flush_deferred(net);
2733 }
2734 EXPORT_SYMBOL(xfrm_garbage_collect_deferred);
2735
2736 static void xfrm_init_pmtu(struct dst_entry *dst)
2737 {
2738         do {
2739                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2740                 u32 pmtu, route_mtu_cached;
2741
2742                 pmtu = dst_mtu(dst->child);
2743                 xdst->child_mtu_cached = pmtu;
2744
2745                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2746
2747                 route_mtu_cached = dst_mtu(xdst->route);
2748                 xdst->route_mtu_cached = route_mtu_cached;
2749
2750                 if (pmtu > route_mtu_cached)
2751                         pmtu = route_mtu_cached;
2752
2753                 dst_metric_set(dst, RTAX_MTU, pmtu);
2754         } while ((dst = dst->next));
2755 }
2756
2757 /* Check that the bundle accepts the flow and its components are
2758  * still valid.
2759  */
2760
2761 static int xfrm_bundle_ok(struct xfrm_dst *first)
2762 {
2763         struct dst_entry *dst = &first->u.dst;
2764         struct xfrm_dst *last;
2765         u32 mtu;
2766
2767         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2768             (dst->dev && !netif_running(dst->dev)))
2769                 return 0;
2770
2771         if (dst->flags & DST_XFRM_QUEUE)
2772                 return 1;
2773
2774         last = NULL;
2775
2776         do {
2777                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2778
2779                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2780                         return 0;
2781                 if (xdst->xfrm_genid != dst->xfrm->genid)
2782                         return 0;
2783                 if (xdst->num_pols > 0 &&
2784                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2785                         return 0;
2786
2787                 mtu = dst_mtu(dst->child);
2788                 if (xdst->child_mtu_cached != mtu) {
2789                         last = xdst;
2790                         xdst->child_mtu_cached = mtu;
2791                 }
2792
2793                 if (!dst_check(xdst->route, xdst->route_cookie))
2794                         return 0;
2795                 mtu = dst_mtu(xdst->route);
2796                 if (xdst->route_mtu_cached != mtu) {
2797                         last = xdst;
2798                         xdst->route_mtu_cached = mtu;
2799                 }
2800
2801                 dst = dst->child;
2802         } while (dst->xfrm);
2803
2804         if (likely(!last))
2805                 return 1;
2806
2807         mtu = last->child_mtu_cached;
2808         for (;;) {
2809                 dst = &last->u.dst;
2810
2811                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2812                 if (mtu > last->route_mtu_cached)
2813                         mtu = last->route_mtu_cached;
2814                 dst_metric_set(dst, RTAX_MTU, mtu);
2815
2816                 if (last == first)
2817                         break;
2818
2819                 last = (struct xfrm_dst *)last->u.dst.next;
2820                 last->child_mtu_cached = mtu;
2821         }
2822
2823         return 1;
2824 }
2825
2826 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2827 {
2828         return dst_metric_advmss(dst->path);
2829 }
2830
2831 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2832 {
2833         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2834
2835         return mtu ? : dst_mtu(dst->path);
2836 }
2837
2838 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2839                                         const void *daddr)
2840 {
2841         const struct dst_entry *path = dst->path;
2842
2843         for (; dst != path; dst = dst->child) {
2844                 const struct xfrm_state *xfrm = dst->xfrm;
2845
2846                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2847                         continue;
2848                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2849                         daddr = xfrm->coaddr;
2850                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2851                         daddr = &xfrm->id.daddr;
2852         }
2853         return daddr;
2854 }
2855
2856 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2857                                            struct sk_buff *skb,
2858                                            const void *daddr)
2859 {
2860         const struct dst_entry *path = dst->path;
2861
2862         if (!skb)
2863                 daddr = xfrm_get_dst_nexthop(dst, daddr);
2864         return path->ops->neigh_lookup(path, skb, daddr);
2865 }
2866
2867 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2868 {
2869         const struct dst_entry *path = dst->path;
2870
2871         daddr = xfrm_get_dst_nexthop(dst, daddr);
2872         path->ops->confirm_neigh(path, daddr);
2873 }
2874
2875 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2876 {
2877         int err = 0;
2878
2879         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2880                 return -EAFNOSUPPORT;
2881
2882         spin_lock(&xfrm_policy_afinfo_lock);
2883         if (unlikely(xfrm_policy_afinfo[family] != NULL))
2884                 err = -EEXIST;
2885         else {
2886                 struct dst_ops *dst_ops = afinfo->dst_ops;
2887                 if (likely(dst_ops->kmem_cachep == NULL))
2888                         dst_ops->kmem_cachep = xfrm_dst_cache;
2889                 if (likely(dst_ops->check == NULL))
2890                         dst_ops->check = xfrm_dst_check;
2891                 if (likely(dst_ops->default_advmss == NULL))
2892                         dst_ops->default_advmss = xfrm_default_advmss;
2893                 if (likely(dst_ops->mtu == NULL))
2894                         dst_ops->mtu = xfrm_mtu;
2895                 if (likely(dst_ops->negative_advice == NULL))
2896                         dst_ops->negative_advice = xfrm_negative_advice;
2897                 if (likely(dst_ops->link_failure == NULL))
2898                         dst_ops->link_failure = xfrm_link_failure;
2899                 if (likely(dst_ops->neigh_lookup == NULL))
2900                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2901                 if (likely(!dst_ops->confirm_neigh))
2902                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
2903                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2904         }
2905         spin_unlock(&xfrm_policy_afinfo_lock);
2906
2907         return err;
2908 }
2909 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2910
2911 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2912 {
2913         struct dst_ops *dst_ops = afinfo->dst_ops;
2914         int i;
2915
2916         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2917                 if (xfrm_policy_afinfo[i] != afinfo)
2918                         continue;
2919                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2920                 break;
2921         }
2922
2923         synchronize_rcu();
2924
2925         dst_ops->kmem_cachep = NULL;
2926         dst_ops->check = NULL;
2927         dst_ops->negative_advice = NULL;
2928         dst_ops->link_failure = NULL;
2929 }
2930 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2931
2932 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2933 {
2934         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2935
2936         switch (event) {
2937         case NETDEV_DOWN:
2938                 xfrm_garbage_collect(dev_net(dev));
2939         }
2940         return NOTIFY_DONE;
2941 }
2942
2943 static struct notifier_block xfrm_dev_notifier = {
2944         .notifier_call  = xfrm_dev_event,
2945 };
2946
2947 #ifdef CONFIG_XFRM_STATISTICS
2948 static int __net_init xfrm_statistics_init(struct net *net)
2949 {
2950         int rv;
2951         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2952         if (!net->mib.xfrm_statistics)
2953                 return -ENOMEM;
2954         rv = xfrm_proc_init(net);
2955         if (rv < 0)
2956                 free_percpu(net->mib.xfrm_statistics);
2957         return rv;
2958 }
2959
2960 static void xfrm_statistics_fini(struct net *net)
2961 {
2962         xfrm_proc_fini(net);
2963         free_percpu(net->mib.xfrm_statistics);
2964 }
2965 #else
2966 static int __net_init xfrm_statistics_init(struct net *net)
2967 {
2968         return 0;
2969 }
2970
2971 static void xfrm_statistics_fini(struct net *net)
2972 {
2973 }
2974 #endif
2975
2976 static int __net_init xfrm_policy_init(struct net *net)
2977 {
2978         unsigned int hmask, sz;
2979         int dir;
2980
2981         if (net_eq(net, &init_net))
2982                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2983                                            sizeof(struct xfrm_dst),
2984                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2985                                            NULL);
2986
2987         hmask = 8 - 1;
2988         sz = (hmask+1) * sizeof(struct hlist_head);
2989
2990         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2991         if (!net->xfrm.policy_byidx)
2992                 goto out_byidx;
2993         net->xfrm.policy_idx_hmask = hmask;
2994
2995         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2996                 struct xfrm_policy_hash *htab;
2997
2998                 net->xfrm.policy_count[dir] = 0;
2999                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
3000                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
3001
3002                 htab = &net->xfrm.policy_bydst[dir];
3003                 htab->table = xfrm_hash_alloc(sz);
3004                 if (!htab->table)
3005                         goto out_bydst;
3006                 htab->hmask = hmask;
3007                 htab->dbits4 = 32;
3008                 htab->sbits4 = 32;
3009                 htab->dbits6 = 128;
3010                 htab->sbits6 = 128;
3011         }
3012         net->xfrm.policy_hthresh.lbits4 = 32;
3013         net->xfrm.policy_hthresh.rbits4 = 32;
3014         net->xfrm.policy_hthresh.lbits6 = 128;
3015         net->xfrm.policy_hthresh.rbits6 = 128;
3016
3017         seqlock_init(&net->xfrm.policy_hthresh.lock);
3018
3019         INIT_LIST_HEAD(&net->xfrm.policy_all);
3020         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
3021         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
3022         if (net_eq(net, &init_net))
3023                 register_netdevice_notifier(&xfrm_dev_notifier);
3024         return 0;
3025
3026 out_bydst:
3027         for (dir--; dir >= 0; dir--) {
3028                 struct xfrm_policy_hash *htab;
3029
3030                 htab = &net->xfrm.policy_bydst[dir];
3031                 xfrm_hash_free(htab->table, sz);
3032         }
3033         xfrm_hash_free(net->xfrm.policy_byidx, sz);
3034 out_byidx:
3035         return -ENOMEM;
3036 }
3037
3038 static void xfrm_policy_fini(struct net *net)
3039 {
3040         unsigned int sz;
3041         int dir;
3042
3043         flush_work(&net->xfrm.policy_hash_work);
3044 #ifdef CONFIG_XFRM_SUB_POLICY
3045         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
3046 #endif
3047         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
3048
3049         WARN_ON(!list_empty(&net->xfrm.policy_all));
3050
3051         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
3052                 struct xfrm_policy_hash *htab;
3053
3054                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
3055
3056                 htab = &net->xfrm.policy_bydst[dir];
3057                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
3058                 WARN_ON(!hlist_empty(htab->table));
3059                 xfrm_hash_free(htab->table, sz);
3060         }
3061
3062         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
3063         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
3064         xfrm_hash_free(net->xfrm.policy_byidx, sz);
3065 }
3066
3067 static int __net_init xfrm_net_init(struct net *net)
3068 {
3069         int rv;
3070
3071         /* Initialize the per-net locks here */
3072         spin_lock_init(&net->xfrm.xfrm_state_lock);
3073         spin_lock_init(&net->xfrm.xfrm_policy_lock);
3074         mutex_init(&net->xfrm.xfrm_cfg_mutex);
3075
3076         rv = xfrm_statistics_init(net);
3077         if (rv < 0)
3078                 goto out_statistics;
3079         rv = xfrm_state_init(net);
3080         if (rv < 0)
3081                 goto out_state;
3082         rv = xfrm_policy_init(net);
3083         if (rv < 0)
3084                 goto out_policy;
3085         rv = xfrm_sysctl_init(net);
3086         if (rv < 0)
3087                 goto out_sysctl;
3088         rv = flow_cache_init(net);
3089         if (rv < 0)
3090                 goto out;
3091
3092         return 0;
3093
3094 out:
3095         xfrm_sysctl_fini(net);
3096 out_sysctl:
3097         xfrm_policy_fini(net);
3098 out_policy:
3099         xfrm_state_fini(net);
3100 out_state:
3101         xfrm_statistics_fini(net);
3102 out_statistics:
3103         return rv;
3104 }
3105
3106 static void __net_exit xfrm_net_exit(struct net *net)
3107 {
3108         flow_cache_fini(net);
3109         xfrm_sysctl_fini(net);
3110         xfrm_policy_fini(net);
3111         xfrm_state_fini(net);
3112         xfrm_statistics_fini(net);
3113 }
3114
3115 static struct pernet_operations __net_initdata xfrm_net_ops = {
3116         .init = xfrm_net_init,
3117         .exit = xfrm_net_exit,
3118 };
3119
3120 void __init xfrm_init(void)
3121 {
3122         flow_cache_hp_init();
3123         register_pernet_subsys(&xfrm_net_ops);
3124         seqcount_init(&xfrm_policy_hash_generation);
3125         xfrm_input_init();
3126 }
3127
3128 #ifdef CONFIG_AUDITSYSCALL
3129 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3130                                          struct audit_buffer *audit_buf)
3131 {
3132         struct xfrm_sec_ctx *ctx = xp->security;
3133         struct xfrm_selector *sel = &xp->selector;
3134
3135         if (ctx)
3136                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3137                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3138
3139         switch (sel->family) {
3140         case AF_INET:
3141                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3142                 if (sel->prefixlen_s != 32)
3143                         audit_log_format(audit_buf, " src_prefixlen=%d",
3144                                          sel->prefixlen_s);
3145                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3146                 if (sel->prefixlen_d != 32)
3147                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3148                                          sel->prefixlen_d);
3149                 break;
3150         case AF_INET6:
3151                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3152                 if (sel->prefixlen_s != 128)
3153                         audit_log_format(audit_buf, " src_prefixlen=%d",
3154                                          sel->prefixlen_s);
3155                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3156                 if (sel->prefixlen_d != 128)
3157                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3158                                          sel->prefixlen_d);
3159                 break;
3160         }
3161 }
3162
3163 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3164 {
3165         struct audit_buffer *audit_buf;
3166
3167         audit_buf = xfrm_audit_start("SPD-add");
3168         if (audit_buf == NULL)
3169                 return;
3170         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3171         audit_log_format(audit_buf, " res=%u", result);
3172         xfrm_audit_common_policyinfo(xp, audit_buf);
3173         audit_log_end(audit_buf);
3174 }
3175 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3176
3177 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3178                               bool task_valid)
3179 {
3180         struct audit_buffer *audit_buf;
3181
3182         audit_buf = xfrm_audit_start("SPD-delete");
3183         if (audit_buf == NULL)
3184                 return;
3185         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3186         audit_log_format(audit_buf, " res=%u", result);
3187         xfrm_audit_common_policyinfo(xp, audit_buf);
3188         audit_log_end(audit_buf);
3189 }
3190 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3191 #endif
3192
3193 #ifdef CONFIG_XFRM_MIGRATE
3194 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3195                                         const struct xfrm_selector *sel_tgt)
3196 {
3197         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3198                 if (sel_tgt->family == sel_cmp->family &&
3199                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3200                                     sel_cmp->family) &&
3201                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3202                                     sel_cmp->family) &&
3203                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3204                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3205                         return true;
3206                 }
3207         } else {
3208                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3209                         return true;
3210                 }
3211         }
3212         return false;
3213 }
3214
3215 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3216                                                     u8 dir, u8 type, struct net *net)
3217 {
3218         struct xfrm_policy *pol, *ret = NULL;
3219         struct hlist_head *chain;
3220         u32 priority = ~0U;
3221
3222         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3223         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3224         hlist_for_each_entry(pol, chain, bydst) {
3225                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3226                     pol->type == type) {
3227                         ret = pol;
3228                         priority = ret->priority;
3229                         break;
3230                 }
3231         }
3232         chain = &net->xfrm.policy_inexact[dir];
3233         hlist_for_each_entry(pol, chain, bydst) {
3234                 if ((pol->priority >= priority) && ret)
3235                         break;
3236
3237                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3238                     pol->type == type) {
3239                         ret = pol;
3240                         break;
3241                 }
3242         }
3243
3244         xfrm_pol_hold(ret);
3245
3246         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3247
3248         return ret;
3249 }
3250
3251 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3252 {
3253         int match = 0;
3254
3255         if (t->mode == m->mode && t->id.proto == m->proto &&
3256             (m->reqid == 0 || t->reqid == m->reqid)) {
3257                 switch (t->mode) {
3258                 case XFRM_MODE_TUNNEL:
3259                 case XFRM_MODE_BEET:
3260                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3261                                             m->old_family) &&
3262                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3263                                             m->old_family)) {
3264                                 match = 1;
3265                         }
3266                         break;
3267                 case XFRM_MODE_TRANSPORT:
3268                         /* in case of transport mode, template does not store
3269                            any IP addresses, hence we just compare mode and
3270                            protocol */
3271                         match = 1;
3272                         break;
3273                 default:
3274                         break;
3275                 }
3276         }
3277         return match;
3278 }
3279
3280 /* update endpoint address(es) of template(s) */
3281 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3282                                struct xfrm_migrate *m, int num_migrate)
3283 {
3284         struct xfrm_migrate *mp;
3285         int i, j, n = 0;
3286
3287         write_lock_bh(&pol->lock);
3288         if (unlikely(pol->walk.dead)) {
3289                 /* target policy has been deleted */
3290                 write_unlock_bh(&pol->lock);
3291                 return -ENOENT;
3292         }
3293
3294         for (i = 0; i < pol->xfrm_nr; i++) {
3295                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3296                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3297                                 continue;
3298                         n++;
3299                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3300                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3301                                 continue;
3302                         /* update endpoints */
3303                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3304                                sizeof(pol->xfrm_vec[i].id.daddr));
3305                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3306                                sizeof(pol->xfrm_vec[i].saddr));
3307                         pol->xfrm_vec[i].encap_family = mp->new_family;
3308                         /* flush bundles */
3309                         atomic_inc(&pol->genid);
3310                 }
3311         }
3312
3313         write_unlock_bh(&pol->lock);
3314
3315         if (!n)
3316                 return -ENODATA;
3317
3318         return 0;
3319 }
3320
3321 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3322 {
3323         int i, j;
3324
3325         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3326                 return -EINVAL;
3327
3328         for (i = 0; i < num_migrate; i++) {
3329                 if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3330                                     m[i].old_family) &&
3331                     xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3332                                     m[i].old_family))
3333                         return -EINVAL;
3334                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3335                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3336                         return -EINVAL;
3337
3338                 /* check if there is any duplicated entry */
3339                 for (j = i + 1; j < num_migrate; j++) {
3340                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3341                                     sizeof(m[i].old_daddr)) &&
3342                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3343                                     sizeof(m[i].old_saddr)) &&
3344                             m[i].proto == m[j].proto &&
3345                             m[i].mode == m[j].mode &&
3346                             m[i].reqid == m[j].reqid &&
3347                             m[i].old_family == m[j].old_family)
3348                                 return -EINVAL;
3349                 }
3350         }
3351
3352         return 0;
3353 }
3354
3355 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3356                  struct xfrm_migrate *m, int num_migrate,
3357                  struct xfrm_kmaddress *k, struct net *net)
3358 {
3359         int i, err, nx_cur = 0, nx_new = 0;
3360         struct xfrm_policy *pol = NULL;
3361         struct xfrm_state *x, *xc;
3362         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3363         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3364         struct xfrm_migrate *mp;
3365
3366         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3367                 goto out;
3368
3369         /* Stage 1 - find policy */
3370         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3371                 err = -ENOENT;
3372                 goto out;
3373         }
3374
3375         /* Stage 2 - find and update state(s) */
3376         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3377                 if ((x = xfrm_migrate_state_find(mp, net))) {
3378                         x_cur[nx_cur] = x;
3379                         nx_cur++;
3380                         if ((xc = xfrm_state_migrate(x, mp))) {
3381                                 x_new[nx_new] = xc;
3382                                 nx_new++;
3383                         } else {
3384                                 err = -ENODATA;
3385                                 goto restore_state;
3386                         }
3387                 }
3388         }
3389
3390         /* Stage 3 - update policy */
3391         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3392                 goto restore_state;
3393
3394         /* Stage 4 - delete old state(s) */
3395         if (nx_cur) {
3396                 xfrm_states_put(x_cur, nx_cur);
3397                 xfrm_states_delete(x_cur, nx_cur);
3398         }
3399
3400         /* Stage 5 - announce */
3401         km_migrate(sel, dir, type, m, num_migrate, k);
3402
3403         xfrm_pol_put(pol);
3404
3405         return 0;
3406 out:
3407         return err;
3408
3409 restore_state:
3410         if (pol)
3411                 xfrm_pol_put(pol);
3412         if (nx_cur)
3413                 xfrm_states_put(x_cur, nx_cur);
3414         if (nx_new)
3415                 xfrm_states_delete(x_new, nx_new);
3416
3417         return err;
3418 }
3419 EXPORT_SYMBOL(xfrm_migrate);
3420 #endif