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)
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,
1255                                                  sk->sk_family);
1256                 int err = 0;
1257
1258                 if (match) {
1259                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1260                                 pol = NULL;
1261                                 goto out;
1262                         }
1263                         err = security_xfrm_policy_lookup(pol->security,
1264                                                       fl->flowi_secid,
1265                                                       policy_to_flow_dir(dir));
1266                         if (!err) {
1267                                 if (!xfrm_pol_hold_rcu(pol))
1268                                         goto again;
1269                         } else if (err == -ESRCH) {
1270                                 pol = NULL;
1271                         } else {
1272                                 pol = ERR_PTR(err);
1273                         }
1274                 } else
1275                         pol = NULL;
1276         }
1277 out:
1278         rcu_read_unlock();
1279         return pol;
1280 }
1281
1282 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1283 {
1284         struct net *net = xp_net(pol);
1285
1286         list_add(&pol->walk.all, &net->xfrm.policy_all);
1287         net->xfrm.policy_count[dir]++;
1288         xfrm_pol_hold(pol);
1289 }
1290
1291 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1292                                                 int dir)
1293 {
1294         struct net *net = xp_net(pol);
1295
1296         if (list_empty(&pol->walk.all))
1297                 return NULL;
1298
1299         /* Socket policies are not hashed. */
1300         if (!hlist_unhashed(&pol->bydst)) {
1301                 hlist_del_rcu(&pol->bydst);
1302                 hlist_del(&pol->byidx);
1303         }
1304
1305         list_del_init(&pol->walk.all);
1306         net->xfrm.policy_count[dir]--;
1307
1308         return pol;
1309 }
1310
1311 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1312 {
1313         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1314 }
1315
1316 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1317 {
1318         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1319 }
1320
1321 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1322 {
1323         struct net *net = xp_net(pol);
1324
1325         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1326         pol = __xfrm_policy_unlink(pol, dir);
1327         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1328         if (pol) {
1329                 xfrm_policy_kill(pol);
1330                 return 0;
1331         }
1332         return -ENOENT;
1333 }
1334 EXPORT_SYMBOL(xfrm_policy_delete);
1335
1336 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1337 {
1338         struct net *net = xp_net(pol);
1339         struct xfrm_policy *old_pol;
1340
1341 #ifdef CONFIG_XFRM_SUB_POLICY
1342         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1343                 return -EINVAL;
1344 #endif
1345
1346         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1347         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1348                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1349         if (pol) {
1350                 pol->curlft.add_time = get_seconds();
1351                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1352                 xfrm_sk_policy_link(pol, dir);
1353         }
1354         rcu_assign_pointer(sk->sk_policy[dir], pol);
1355         if (old_pol) {
1356                 if (pol)
1357                         xfrm_policy_requeue(old_pol, pol);
1358
1359                 /* Unlinking succeeds always. This is the only function
1360                  * allowed to delete or replace socket policy.
1361                  */
1362                 xfrm_sk_policy_unlink(old_pol, dir);
1363         }
1364         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1365
1366         if (old_pol) {
1367                 xfrm_policy_kill(old_pol);
1368         }
1369         return 0;
1370 }
1371
1372 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1373 {
1374         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1375         struct net *net = xp_net(old);
1376
1377         if (newp) {
1378                 newp->selector = old->selector;
1379                 if (security_xfrm_policy_clone(old->security,
1380                                                &newp->security)) {
1381                         kfree(newp);
1382                         return NULL;  /* ENOMEM */
1383                 }
1384                 newp->lft = old->lft;
1385                 newp->curlft = old->curlft;
1386                 newp->mark = old->mark;
1387                 newp->action = old->action;
1388                 newp->flags = old->flags;
1389                 newp->xfrm_nr = old->xfrm_nr;
1390                 newp->index = old->index;
1391                 newp->type = old->type;
1392                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1393                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1394                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1395                 xfrm_sk_policy_link(newp, dir);
1396                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1397                 xfrm_pol_put(newp);
1398         }
1399         return newp;
1400 }
1401
1402 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1403 {
1404         const struct xfrm_policy *p;
1405         struct xfrm_policy *np;
1406         int i, ret = 0;
1407
1408         rcu_read_lock();
1409         for (i = 0; i < 2; i++) {
1410                 p = rcu_dereference(osk->sk_policy[i]);
1411                 if (p) {
1412                         np = clone_policy(p, i);
1413                         if (unlikely(!np)) {
1414                                 ret = -ENOMEM;
1415                                 break;
1416                         }
1417                         rcu_assign_pointer(sk->sk_policy[i], np);
1418                 }
1419         }
1420         rcu_read_unlock();
1421         return ret;
1422 }
1423
1424 static int
1425 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1426                xfrm_address_t *remote, unsigned short family)
1427 {
1428         int err;
1429         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1430
1431         if (unlikely(afinfo == NULL))
1432                 return -EINVAL;
1433         err = afinfo->get_saddr(net, oif, local, remote);
1434         rcu_read_unlock();
1435         return err;
1436 }
1437
1438 /* Resolve list of templates for the flow, given policy. */
1439
1440 static int
1441 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1442                       struct xfrm_state **xfrm, unsigned short family)
1443 {
1444         struct net *net = xp_net(policy);
1445         int nx;
1446         int i, error;
1447         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1448         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1449         xfrm_address_t tmp;
1450
1451         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1452                 struct xfrm_state *x;
1453                 xfrm_address_t *remote = daddr;
1454                 xfrm_address_t *local  = saddr;
1455                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1456
1457                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1458                     tmpl->mode == XFRM_MODE_BEET) {
1459                         remote = &tmpl->id.daddr;
1460                         local = &tmpl->saddr;
1461                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1462                                 error = xfrm_get_saddr(net, fl->flowi_oif,
1463                                                        &tmp, remote,
1464                                                        tmpl->encap_family);
1465                                 if (error)
1466                                         goto fail;
1467                                 local = &tmp;
1468                         }
1469                 }
1470
1471                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1472
1473                 if (x && x->km.state == XFRM_STATE_VALID) {
1474                         xfrm[nx++] = x;
1475                         daddr = remote;
1476                         saddr = local;
1477                         continue;
1478                 }
1479                 if (x) {
1480                         error = (x->km.state == XFRM_STATE_ERROR ?
1481                                  -EINVAL : -EAGAIN);
1482                         xfrm_state_put(x);
1483                 } else if (error == -ESRCH) {
1484                         error = -EAGAIN;
1485                 }
1486
1487                 if (!tmpl->optional)
1488                         goto fail;
1489         }
1490         return nx;
1491
1492 fail:
1493         for (nx--; nx >= 0; nx--)
1494                 xfrm_state_put(xfrm[nx]);
1495         return error;
1496 }
1497
1498 static int
1499 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1500                   struct xfrm_state **xfrm, unsigned short family)
1501 {
1502         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1503         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1504         int cnx = 0;
1505         int error;
1506         int ret;
1507         int i;
1508
1509         for (i = 0; i < npols; i++) {
1510                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1511                         error = -ENOBUFS;
1512                         goto fail;
1513                 }
1514
1515                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1516                 if (ret < 0) {
1517                         error = ret;
1518                         goto fail;
1519                 } else
1520                         cnx += ret;
1521         }
1522
1523         /* found states are sorted for outbound processing */
1524         if (npols > 1)
1525                 xfrm_state_sort(xfrm, tpp, cnx, family);
1526
1527         return cnx;
1528
1529  fail:
1530         for (cnx--; cnx >= 0; cnx--)
1531                 xfrm_state_put(tpp[cnx]);
1532         return error;
1533
1534 }
1535
1536 static int xfrm_get_tos(const struct flowi *fl, int family)
1537 {
1538         const struct xfrm_policy_afinfo *afinfo;
1539         int tos = 0;
1540
1541         afinfo = xfrm_policy_get_afinfo(family);
1542         tos = afinfo ? afinfo->get_tos(fl) : 0;
1543
1544         rcu_read_unlock();
1545
1546         return tos;
1547 }
1548
1549 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1550 {
1551         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1552         struct dst_entry *dst = &xdst->u.dst;
1553
1554         if (xdst->route == NULL) {
1555                 /* Dummy bundle - if it has xfrms we were not
1556                  * able to build bundle as template resolution failed.
1557                  * It means we need to try again resolving. */
1558                 if (xdst->num_xfrms > 0)
1559                         return NULL;
1560         } else if (dst->flags & DST_XFRM_QUEUE) {
1561                 return NULL;
1562         } else {
1563                 /* Real bundle */
1564                 if (stale_bundle(dst))
1565                         return NULL;
1566         }
1567
1568         dst_hold(dst);
1569         return flo;
1570 }
1571
1572 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1573 {
1574         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1575         struct dst_entry *dst = &xdst->u.dst;
1576
1577         if (!xdst->route)
1578                 return 0;
1579         if (stale_bundle(dst))
1580                 return 0;
1581
1582         return 1;
1583 }
1584
1585 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1586 {
1587         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1588         struct dst_entry *dst = &xdst->u.dst;
1589
1590         dst_free(dst);
1591 }
1592
1593 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1594         .get = xfrm_bundle_flo_get,
1595         .check = xfrm_bundle_flo_check,
1596         .delete = xfrm_bundle_flo_delete,
1597 };
1598
1599 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1600 {
1601         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1602         struct dst_ops *dst_ops;
1603         struct xfrm_dst *xdst;
1604
1605         if (!afinfo)
1606                 return ERR_PTR(-EINVAL);
1607
1608         switch (family) {
1609         case AF_INET:
1610                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1611                 break;
1612 #if IS_ENABLED(CONFIG_IPV6)
1613         case AF_INET6:
1614                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1615                 break;
1616 #endif
1617         default:
1618                 BUG();
1619         }
1620         xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1621
1622         if (likely(xdst)) {
1623                 struct dst_entry *dst = &xdst->u.dst;
1624
1625                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1626                 xdst->flo.ops = &xfrm_bundle_fc_ops;
1627         } else
1628                 xdst = ERR_PTR(-ENOBUFS);
1629
1630         rcu_read_unlock();
1631
1632         return xdst;
1633 }
1634
1635 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1636                                  int nfheader_len)
1637 {
1638         const struct xfrm_policy_afinfo *afinfo =
1639                 xfrm_policy_get_afinfo(dst->ops->family);
1640         int err;
1641
1642         if (!afinfo)
1643                 return -EINVAL;
1644
1645         err = afinfo->init_path(path, dst, nfheader_len);
1646
1647         rcu_read_unlock();
1648
1649         return err;
1650 }
1651
1652 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1653                                 const struct flowi *fl)
1654 {
1655         const struct xfrm_policy_afinfo *afinfo =
1656                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1657         int err;
1658
1659         if (!afinfo)
1660                 return -EINVAL;
1661
1662         err = afinfo->fill_dst(xdst, dev, fl);
1663
1664         rcu_read_unlock();
1665
1666         return err;
1667 }
1668
1669
1670 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1671  * all the metrics... Shortly, bundle a bundle.
1672  */
1673
1674 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1675                                             struct xfrm_state **xfrm, int nx,
1676                                             const struct flowi *fl,
1677                                             struct dst_entry *dst)
1678 {
1679         struct net *net = xp_net(policy);
1680         unsigned long now = jiffies;
1681         struct net_device *dev;
1682         struct xfrm_mode *inner_mode;
1683         struct dst_entry *dst_prev = NULL;
1684         struct dst_entry *dst0 = NULL;
1685         int i = 0;
1686         int err;
1687         int header_len = 0;
1688         int nfheader_len = 0;
1689         int trailer_len = 0;
1690         int tos;
1691         int family = policy->selector.family;
1692         xfrm_address_t saddr, daddr;
1693
1694         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1695
1696         tos = xfrm_get_tos(fl, family);
1697
1698         dst_hold(dst);
1699
1700         for (; i < nx; i++) {
1701                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1702                 struct dst_entry *dst1 = &xdst->u.dst;
1703
1704                 err = PTR_ERR(xdst);
1705                 if (IS_ERR(xdst)) {
1706                         dst_release(dst);
1707                         goto put_states;
1708                 }
1709
1710                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1711                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1712                                                         xfrm_af2proto(family));
1713                         if (!inner_mode) {
1714                                 err = -EAFNOSUPPORT;
1715                                 dst_release(dst);
1716                                 goto put_states;
1717                         }
1718                 } else
1719                         inner_mode = xfrm[i]->inner_mode;
1720
1721                 if (!dst_prev)
1722                         dst0 = dst1;
1723                 else {
1724                         dst_prev->child = dst_clone(dst1);
1725                         dst1->flags |= DST_NOHASH;
1726                 }
1727
1728                 xdst->route = dst;
1729                 dst_copy_metrics(dst1, dst);
1730
1731                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1732                         family = xfrm[i]->props.family;
1733                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1734                                               &saddr, &daddr, family);
1735                         err = PTR_ERR(dst);
1736                         if (IS_ERR(dst))
1737                                 goto put_states;
1738                 } else
1739                         dst_hold(dst);
1740
1741                 dst1->xfrm = xfrm[i];
1742                 xdst->xfrm_genid = xfrm[i]->genid;
1743
1744                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1745                 dst1->flags |= DST_HOST;
1746                 dst1->lastuse = now;
1747
1748                 dst1->input = dst_discard;
1749                 dst1->output = inner_mode->afinfo->output;
1750
1751                 dst1->next = dst_prev;
1752                 dst_prev = dst1;
1753
1754                 header_len += xfrm[i]->props.header_len;
1755                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1756                         nfheader_len += xfrm[i]->props.header_len;
1757                 trailer_len += xfrm[i]->props.trailer_len;
1758         }
1759
1760         dst_prev->child = dst;
1761         dst0->path = dst;
1762
1763         err = -ENODEV;
1764         dev = dst->dev;
1765         if (!dev)
1766                 goto free_dst;
1767
1768         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1769         xfrm_init_pmtu(dst_prev);
1770
1771         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1772                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1773
1774                 err = xfrm_fill_dst(xdst, dev, fl);
1775                 if (err)
1776                         goto free_dst;
1777
1778                 dst_prev->header_len = header_len;
1779                 dst_prev->trailer_len = trailer_len;
1780                 header_len -= xdst->u.dst.xfrm->props.header_len;
1781                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1782         }
1783
1784 out:
1785         return dst0;
1786
1787 put_states:
1788         for (; i < nx; i++)
1789                 xfrm_state_put(xfrm[i]);
1790 free_dst:
1791         if (dst0)
1792                 dst_free(dst0);
1793         dst0 = ERR_PTR(err);
1794         goto out;
1795 }
1796
1797 #ifdef CONFIG_XFRM_SUB_POLICY
1798 static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
1799 {
1800         if (!*target) {
1801                 *target = kmalloc(size, GFP_ATOMIC);
1802                 if (!*target)
1803                         return -ENOMEM;
1804         }
1805
1806         memcpy(*target, src, size);
1807         return 0;
1808 }
1809 #endif
1810
1811 static int xfrm_dst_update_parent(struct dst_entry *dst,
1812                                   const struct xfrm_selector *sel)
1813 {
1814 #ifdef CONFIG_XFRM_SUB_POLICY
1815         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1816         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1817                                    sel, sizeof(*sel));
1818 #else
1819         return 0;
1820 #endif
1821 }
1822
1823 static int xfrm_dst_update_origin(struct dst_entry *dst,
1824                                   const struct flowi *fl)
1825 {
1826 #ifdef CONFIG_XFRM_SUB_POLICY
1827         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1828         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1829 #else
1830         return 0;
1831 #endif
1832 }
1833
1834 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1835                                 struct xfrm_policy **pols,
1836                                 int *num_pols, int *num_xfrms)
1837 {
1838         int i;
1839
1840         if (*num_pols == 0 || !pols[0]) {
1841                 *num_pols = 0;
1842                 *num_xfrms = 0;
1843                 return 0;
1844         }
1845         if (IS_ERR(pols[0]))
1846                 return PTR_ERR(pols[0]);
1847
1848         *num_xfrms = pols[0]->xfrm_nr;
1849
1850 #ifdef CONFIG_XFRM_SUB_POLICY
1851         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1852             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1853                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1854                                                     XFRM_POLICY_TYPE_MAIN,
1855                                                     fl, family,
1856                                                     XFRM_POLICY_OUT);
1857                 if (pols[1]) {
1858                         if (IS_ERR(pols[1])) {
1859                                 xfrm_pols_put(pols, *num_pols);
1860                                 return PTR_ERR(pols[1]);
1861                         }
1862                         (*num_pols)++;
1863                         (*num_xfrms) += pols[1]->xfrm_nr;
1864                 }
1865         }
1866 #endif
1867         for (i = 0; i < *num_pols; i++) {
1868                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1869                         *num_xfrms = -1;
1870                         break;
1871                 }
1872         }
1873
1874         return 0;
1875
1876 }
1877
1878 static struct xfrm_dst *
1879 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1880                                const struct flowi *fl, u16 family,
1881                                struct dst_entry *dst_orig)
1882 {
1883         struct net *net = xp_net(pols[0]);
1884         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1885         struct dst_entry *dst;
1886         struct xfrm_dst *xdst;
1887         int err;
1888
1889         /* Try to instantiate a bundle */
1890         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1891         if (err <= 0) {
1892                 if (err != 0 && err != -EAGAIN)
1893                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1894                 return ERR_PTR(err);
1895         }
1896
1897         dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1898         if (IS_ERR(dst)) {
1899                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1900                 return ERR_CAST(dst);
1901         }
1902
1903         xdst = (struct xfrm_dst *)dst;
1904         xdst->num_xfrms = err;
1905         if (num_pols > 1)
1906                 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1907         else
1908                 err = xfrm_dst_update_origin(dst, fl);
1909         if (unlikely(err)) {
1910                 dst_free(dst);
1911                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1912                 return ERR_PTR(err);
1913         }
1914
1915         xdst->num_pols = num_pols;
1916         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1917         xdst->policy_genid = atomic_read(&pols[0]->genid);
1918
1919         return xdst;
1920 }
1921
1922 static void xfrm_policy_queue_process(unsigned long arg)
1923 {
1924         struct sk_buff *skb;
1925         struct sock *sk;
1926         struct dst_entry *dst;
1927         struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1928         struct net *net = xp_net(pol);
1929         struct xfrm_policy_queue *pq = &pol->polq;
1930         struct flowi fl;
1931         struct sk_buff_head list;
1932
1933         spin_lock(&pq->hold_queue.lock);
1934         skb = skb_peek(&pq->hold_queue);
1935         if (!skb) {
1936                 spin_unlock(&pq->hold_queue.lock);
1937                 goto out;
1938         }
1939         dst = skb_dst(skb);
1940         sk = skb->sk;
1941         xfrm_decode_session(skb, &fl, dst->ops->family);
1942         spin_unlock(&pq->hold_queue.lock);
1943
1944         dst_hold(dst->path);
1945         dst = xfrm_lookup(net, dst->path, &fl, sk, 0);
1946         if (IS_ERR(dst))
1947                 goto purge_queue;
1948
1949         if (dst->flags & DST_XFRM_QUEUE) {
1950                 dst_release(dst);
1951
1952                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1953                         goto purge_queue;
1954
1955                 pq->timeout = pq->timeout << 1;
1956                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1957                         xfrm_pol_hold(pol);
1958         goto out;
1959         }
1960
1961         dst_release(dst);
1962
1963         __skb_queue_head_init(&list);
1964
1965         spin_lock(&pq->hold_queue.lock);
1966         pq->timeout = 0;
1967         skb_queue_splice_init(&pq->hold_queue, &list);
1968         spin_unlock(&pq->hold_queue.lock);
1969
1970         while (!skb_queue_empty(&list)) {
1971                 skb = __skb_dequeue(&list);
1972
1973                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1974                 dst_hold(skb_dst(skb)->path);
1975                 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0);
1976                 if (IS_ERR(dst)) {
1977                         kfree_skb(skb);
1978                         continue;
1979                 }
1980
1981                 nf_reset(skb);
1982                 skb_dst_drop(skb);
1983                 skb_dst_set(skb, dst);
1984
1985                 dst_output(net, skb->sk, skb);
1986         }
1987
1988 out:
1989         xfrm_pol_put(pol);
1990         return;
1991
1992 purge_queue:
1993         pq->timeout = 0;
1994         skb_queue_purge(&pq->hold_queue);
1995         xfrm_pol_put(pol);
1996 }
1997
1998 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1999 {
2000         unsigned long sched_next;
2001         struct dst_entry *dst = skb_dst(skb);
2002         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2003         struct xfrm_policy *pol = xdst->pols[0];
2004         struct xfrm_policy_queue *pq = &pol->polq;
2005
2006         if (unlikely(skb_fclone_busy(sk, skb))) {
2007                 kfree_skb(skb);
2008                 return 0;
2009         }
2010
2011         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2012                 kfree_skb(skb);
2013                 return -EAGAIN;
2014         }
2015
2016         skb_dst_force(skb);
2017
2018         spin_lock_bh(&pq->hold_queue.lock);
2019
2020         if (!pq->timeout)
2021                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2022
2023         sched_next = jiffies + pq->timeout;
2024
2025         if (del_timer(&pq->hold_timer)) {
2026                 if (time_before(pq->hold_timer.expires, sched_next))
2027                         sched_next = pq->hold_timer.expires;
2028                 xfrm_pol_put(pol);
2029         }
2030
2031         __skb_queue_tail(&pq->hold_queue, skb);
2032         if (!mod_timer(&pq->hold_timer, sched_next))
2033                 xfrm_pol_hold(pol);
2034
2035         spin_unlock_bh(&pq->hold_queue.lock);
2036
2037         return 0;
2038 }
2039
2040 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2041                                                  struct xfrm_flo *xflo,
2042                                                  const struct flowi *fl,
2043                                                  int num_xfrms,
2044                                                  u16 family)
2045 {
2046         int err;
2047         struct net_device *dev;
2048         struct dst_entry *dst;
2049         struct dst_entry *dst1;
2050         struct xfrm_dst *xdst;
2051
2052         xdst = xfrm_alloc_dst(net, family);
2053         if (IS_ERR(xdst))
2054                 return xdst;
2055
2056         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2057             net->xfrm.sysctl_larval_drop ||
2058             num_xfrms <= 0)
2059                 return xdst;
2060
2061         dst = xflo->dst_orig;
2062         dst1 = &xdst->u.dst;
2063         dst_hold(dst);
2064         xdst->route = dst;
2065
2066         dst_copy_metrics(dst1, dst);
2067
2068         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2069         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2070         dst1->lastuse = jiffies;
2071
2072         dst1->input = dst_discard;
2073         dst1->output = xdst_queue_output;
2074
2075         dst_hold(dst);
2076         dst1->child = dst;
2077         dst1->path = dst;
2078
2079         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2080
2081         err = -ENODEV;
2082         dev = dst->dev;
2083         if (!dev)
2084                 goto free_dst;
2085
2086         err = xfrm_fill_dst(xdst, dev, fl);
2087         if (err)
2088                 goto free_dst;
2089
2090 out:
2091         return xdst;
2092
2093 free_dst:
2094         dst_release(dst1);
2095         xdst = ERR_PTR(err);
2096         goto out;
2097 }
2098
2099 static struct flow_cache_object *
2100 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
2101                    struct flow_cache_object *oldflo, void *ctx)
2102 {
2103         struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
2104         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2105         struct xfrm_dst *xdst, *new_xdst;
2106         int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
2107
2108         /* Check if the policies from old bundle are usable */
2109         xdst = NULL;
2110         if (oldflo) {
2111                 xdst = container_of(oldflo, struct xfrm_dst, flo);
2112                 num_pols = xdst->num_pols;
2113                 num_xfrms = xdst->num_xfrms;
2114                 pol_dead = 0;
2115                 for (i = 0; i < num_pols; i++) {
2116                         pols[i] = xdst->pols[i];
2117                         pol_dead |= pols[i]->walk.dead;
2118                 }
2119                 if (pol_dead) {
2120                         dst_free(&xdst->u.dst);
2121                         xdst = NULL;
2122                         num_pols = 0;
2123                         num_xfrms = 0;
2124                         oldflo = NULL;
2125                 }
2126         }
2127
2128         /* Resolve policies to use if we couldn't get them from
2129          * previous cache entry */
2130         if (xdst == NULL) {
2131                 num_pols = 1;
2132                 pols[0] = __xfrm_policy_lookup(net, fl, family,
2133                                                flow_to_policy_dir(dir));
2134                 err = xfrm_expand_policies(fl, family, pols,
2135                                            &num_pols, &num_xfrms);
2136                 if (err < 0)
2137                         goto inc_error;
2138                 if (num_pols == 0)
2139                         return NULL;
2140                 if (num_xfrms <= 0)
2141                         goto make_dummy_bundle;
2142         }
2143
2144         new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2145                                                   xflo->dst_orig);
2146         if (IS_ERR(new_xdst)) {
2147                 err = PTR_ERR(new_xdst);
2148                 if (err != -EAGAIN)
2149                         goto error;
2150                 if (oldflo == NULL)
2151                         goto make_dummy_bundle;
2152                 dst_hold(&xdst->u.dst);
2153                 return oldflo;
2154         } else if (new_xdst == NULL) {
2155                 num_xfrms = 0;
2156                 if (oldflo == NULL)
2157                         goto make_dummy_bundle;
2158                 xdst->num_xfrms = 0;
2159                 dst_hold(&xdst->u.dst);
2160                 return oldflo;
2161         }
2162
2163         /* Kill the previous bundle */
2164         if (xdst) {
2165                 /* The policies were stolen for newly generated bundle */
2166                 xdst->num_pols = 0;
2167                 dst_free(&xdst->u.dst);
2168         }
2169
2170         /* Flow cache does not have reference, it dst_free()'s,
2171          * but we do need to return one reference for original caller */
2172         dst_hold(&new_xdst->u.dst);
2173         return &new_xdst->flo;
2174
2175 make_dummy_bundle:
2176         /* We found policies, but there's no bundles to instantiate:
2177          * either because the policy blocks, has no transformations or
2178          * we could not build template (no xfrm_states).*/
2179         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2180         if (IS_ERR(xdst)) {
2181                 xfrm_pols_put(pols, num_pols);
2182                 return ERR_CAST(xdst);
2183         }
2184         xdst->num_pols = num_pols;
2185         xdst->num_xfrms = num_xfrms;
2186         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2187
2188         dst_hold(&xdst->u.dst);
2189         return &xdst->flo;
2190
2191 inc_error:
2192         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2193 error:
2194         if (xdst != NULL)
2195                 dst_free(&xdst->u.dst);
2196         else
2197                 xfrm_pols_put(pols, num_pols);
2198         return ERR_PTR(err);
2199 }
2200
2201 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2202                                         struct dst_entry *dst_orig)
2203 {
2204         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2205         struct dst_entry *ret;
2206
2207         if (!afinfo) {
2208                 dst_release(dst_orig);
2209                 return ERR_PTR(-EINVAL);
2210         } else {
2211                 ret = afinfo->blackhole_route(net, dst_orig);
2212         }
2213         rcu_read_unlock();
2214
2215         return ret;
2216 }
2217
2218 /* Main function: finds/creates a bundle for given flow.
2219  *
2220  * At the moment we eat a raw IP route. Mostly to speed up lookups
2221  * on interfaces with disabled IPsec.
2222  */
2223 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2224                               const struct flowi *fl,
2225                               const struct sock *sk, int flags)
2226 {
2227         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2228         struct flow_cache_object *flo;
2229         struct xfrm_dst *xdst;
2230         struct dst_entry *dst, *route;
2231         u16 family = dst_orig->ops->family;
2232         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2233         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2234
2235         dst = NULL;
2236         xdst = NULL;
2237         route = NULL;
2238
2239         sk = sk_const_to_full_sk(sk);
2240         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2241                 num_pols = 1;
2242                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2243                 err = xfrm_expand_policies(fl, family, pols,
2244                                            &num_pols, &num_xfrms);
2245                 if (err < 0)
2246                         goto dropdst;
2247
2248                 if (num_pols) {
2249                         if (num_xfrms <= 0) {
2250                                 drop_pols = num_pols;
2251                                 goto no_transform;
2252                         }
2253
2254                         xdst = xfrm_resolve_and_create_bundle(
2255                                         pols, num_pols, fl,
2256                                         family, dst_orig);
2257                         if (IS_ERR(xdst)) {
2258                                 xfrm_pols_put(pols, num_pols);
2259                                 err = PTR_ERR(xdst);
2260                                 goto dropdst;
2261                         } else if (xdst == NULL) {
2262                                 num_xfrms = 0;
2263                                 drop_pols = num_pols;
2264                                 goto no_transform;
2265                         }
2266
2267                         dst_hold(&xdst->u.dst);
2268                         xdst->u.dst.flags |= DST_NOCACHE;
2269                         route = xdst->route;
2270                 }
2271         }
2272
2273         if (xdst == NULL) {
2274                 struct xfrm_flo xflo;
2275
2276                 xflo.dst_orig = dst_orig;
2277                 xflo.flags = flags;
2278
2279                 /* To accelerate a bit...  */
2280                 if ((dst_orig->flags & DST_NOXFRM) ||
2281                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2282                         goto nopol;
2283
2284                 flo = flow_cache_lookup(net, fl, family, dir,
2285                                         xfrm_bundle_lookup, &xflo);
2286                 if (flo == NULL)
2287                         goto nopol;
2288                 if (IS_ERR(flo)) {
2289                         err = PTR_ERR(flo);
2290                         goto dropdst;
2291                 }
2292                 xdst = container_of(flo, struct xfrm_dst, flo);
2293
2294                 num_pols = xdst->num_pols;
2295                 num_xfrms = xdst->num_xfrms;
2296                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2297                 route = xdst->route;
2298         }
2299
2300         dst = &xdst->u.dst;
2301         if (route == NULL && num_xfrms > 0) {
2302                 /* The only case when xfrm_bundle_lookup() returns a
2303                  * bundle with null route, is when the template could
2304                  * not be resolved. It means policies are there, but
2305                  * bundle could not be created, since we don't yet
2306                  * have the xfrm_state's. We need to wait for KM to
2307                  * negotiate new SA's or bail out with error.*/
2308                 if (net->xfrm.sysctl_larval_drop) {
2309                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2310                         err = -EREMOTE;
2311                         goto error;
2312                 }
2313
2314                 err = -EAGAIN;
2315
2316                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2317                 goto error;
2318         }
2319
2320 no_transform:
2321         if (num_pols == 0)
2322                 goto nopol;
2323
2324         if ((flags & XFRM_LOOKUP_ICMP) &&
2325             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2326                 err = -ENOENT;
2327                 goto error;
2328         }
2329
2330         for (i = 0; i < num_pols; i++)
2331                 pols[i]->curlft.use_time = get_seconds();
2332
2333         if (num_xfrms < 0) {
2334                 /* Prohibit the flow */
2335                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2336                 err = -EPERM;
2337                 goto error;
2338         } else if (num_xfrms > 0) {
2339                 /* Flow transformed */
2340                 dst_release(dst_orig);
2341         } else {
2342                 /* Flow passes untransformed */
2343                 dst_release(dst);
2344                 dst = dst_orig;
2345         }
2346 ok:
2347         xfrm_pols_put(pols, drop_pols);
2348         if (dst && dst->xfrm &&
2349             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2350                 dst->flags |= DST_XFRM_TUNNEL;
2351         return dst;
2352
2353 nopol:
2354         if (!(flags & XFRM_LOOKUP_ICMP)) {
2355                 dst = dst_orig;
2356                 goto ok;
2357         }
2358         err = -ENOENT;
2359 error:
2360         dst_release(dst);
2361 dropdst:
2362         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2363                 dst_release(dst_orig);
2364         xfrm_pols_put(pols, drop_pols);
2365         return ERR_PTR(err);
2366 }
2367 EXPORT_SYMBOL(xfrm_lookup);
2368
2369 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2370  * Otherwise we may send out blackholed packets.
2371  */
2372 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2373                                     const struct flowi *fl,
2374                                     const struct sock *sk, int flags)
2375 {
2376         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2377                                             flags | XFRM_LOOKUP_QUEUE |
2378                                             XFRM_LOOKUP_KEEP_DST_REF);
2379
2380         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2381                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2382
2383         return dst;
2384 }
2385 EXPORT_SYMBOL(xfrm_lookup_route);
2386
2387 static inline int
2388 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2389 {
2390         struct xfrm_state *x;
2391
2392         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2393                 return 0;
2394         x = skb->sp->xvec[idx];
2395         if (!x->type->reject)
2396                 return 0;
2397         return x->type->reject(x, skb, fl);
2398 }
2399
2400 /* When skb is transformed back to its "native" form, we have to
2401  * check policy restrictions. At the moment we make this in maximally
2402  * stupid way. Shame on me. :-) Of course, connected sockets must
2403  * have policy cached at them.
2404  */
2405
2406 static inline int
2407 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2408               unsigned short family)
2409 {
2410         if (xfrm_state_kern(x))
2411                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2412         return  x->id.proto == tmpl->id.proto &&
2413                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2414                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2415                 x->props.mode == tmpl->mode &&
2416                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2417                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2418                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2419                   xfrm_state_addr_cmp(tmpl, x, family));
2420 }
2421
2422 /*
2423  * 0 or more than 0 is returned when validation is succeeded (either bypass
2424  * because of optional transport mode, or next index of the mathced secpath
2425  * state with the template.
2426  * -1 is returned when no matching template is found.
2427  * Otherwise "-2 - errored_index" is returned.
2428  */
2429 static inline int
2430 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2431                unsigned short family)
2432 {
2433         int idx = start;
2434
2435         if (tmpl->optional) {
2436                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2437                         return start;
2438         } else
2439                 start = -1;
2440         for (; idx < sp->len; idx++) {
2441                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2442                         return ++idx;
2443                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2444                         if (start == -1)
2445                                 start = -2-idx;
2446                         break;
2447                 }
2448         }
2449         return start;
2450 }
2451
2452 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2453                           unsigned int family, int reverse)
2454 {
2455         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2456         int err;
2457
2458         if (unlikely(afinfo == NULL))
2459                 return -EAFNOSUPPORT;
2460
2461         afinfo->decode_session(skb, fl, reverse);
2462         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2463         rcu_read_unlock();
2464         return err;
2465 }
2466 EXPORT_SYMBOL(__xfrm_decode_session);
2467
2468 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2469 {
2470         for (; k < sp->len; k++) {
2471                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2472                         *idxp = k;
2473                         return 1;
2474                 }
2475         }
2476
2477         return 0;
2478 }
2479
2480 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2481                         unsigned short family)
2482 {
2483         struct net *net = dev_net(skb->dev);
2484         struct xfrm_policy *pol;
2485         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2486         int npols = 0;
2487         int xfrm_nr;
2488         int pi;
2489         int reverse;
2490         struct flowi fl;
2491         u8 fl_dir;
2492         int xerr_idx = -1;
2493
2494         reverse = dir & ~XFRM_POLICY_MASK;
2495         dir &= XFRM_POLICY_MASK;
2496         fl_dir = policy_to_flow_dir(dir);
2497
2498         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2499                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2500                 return 0;
2501         }
2502
2503         nf_nat_decode_session(skb, &fl, family);
2504
2505         /* First, check used SA against their selectors. */
2506         if (skb->sp) {
2507                 int i;
2508
2509                 for (i = skb->sp->len-1; i >= 0; i--) {
2510                         struct xfrm_state *x = skb->sp->xvec[i];
2511                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2512                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2513                                 return 0;
2514                         }
2515                 }
2516         }
2517
2518         pol = NULL;
2519         sk = sk_to_full_sk(sk);
2520         if (sk && sk->sk_policy[dir]) {
2521                 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2522                 if (IS_ERR(pol)) {
2523                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2524                         return 0;
2525                 }
2526         }
2527
2528         if (!pol) {
2529                 struct flow_cache_object *flo;
2530
2531                 flo = flow_cache_lookup(net, &fl, family, fl_dir,
2532                                         xfrm_policy_lookup, NULL);
2533                 if (IS_ERR_OR_NULL(flo))
2534                         pol = ERR_CAST(flo);
2535                 else
2536                         pol = container_of(flo, struct xfrm_policy, flo);
2537         }
2538
2539         if (IS_ERR(pol)) {
2540                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2541                 return 0;
2542         }
2543
2544         if (!pol) {
2545                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2546                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2547                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2548                         return 0;
2549                 }
2550                 return 1;
2551         }
2552
2553         pol->curlft.use_time = get_seconds();
2554
2555         pols[0] = pol;
2556         npols++;
2557 #ifdef CONFIG_XFRM_SUB_POLICY
2558         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2559                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2560                                                     &fl, family,
2561                                                     XFRM_POLICY_IN);
2562                 if (pols[1]) {
2563                         if (IS_ERR(pols[1])) {
2564                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2565                                 return 0;
2566                         }
2567                         pols[1]->curlft.use_time = get_seconds();
2568                         npols++;
2569                 }
2570         }
2571 #endif
2572
2573         if (pol->action == XFRM_POLICY_ALLOW) {
2574                 struct sec_path *sp;
2575                 static struct sec_path dummy;
2576                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2577                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2578                 struct xfrm_tmpl **tpp = tp;
2579                 int ti = 0;
2580                 int i, k;
2581
2582                 if ((sp = skb->sp) == NULL)
2583                         sp = &dummy;
2584
2585                 for (pi = 0; pi < npols; pi++) {
2586                         if (pols[pi] != pol &&
2587                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2588                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2589                                 goto reject;
2590                         }
2591                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2592                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2593                                 goto reject_error;
2594                         }
2595                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2596                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2597                 }
2598                 xfrm_nr = ti;
2599                 if (npols > 1) {
2600                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2601                         tpp = stp;
2602                 }
2603
2604                 /* For each tunnel xfrm, find the first matching tmpl.
2605                  * For each tmpl before that, find corresponding xfrm.
2606                  * Order is _important_. Later we will implement
2607                  * some barriers, but at the moment barriers
2608                  * are implied between each two transformations.
2609                  */
2610                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2611                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2612                         if (k < 0) {
2613                                 if (k < -1)
2614                                         /* "-2 - errored_index" returned */
2615                                         xerr_idx = -(2+k);
2616                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2617                                 goto reject;
2618                         }
2619                 }
2620
2621                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2622                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2623                         goto reject;
2624                 }
2625
2626                 xfrm_pols_put(pols, npols);
2627                 return 1;
2628         }
2629         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2630
2631 reject:
2632         xfrm_secpath_reject(xerr_idx, skb, &fl);
2633 reject_error:
2634         xfrm_pols_put(pols, npols);
2635         return 0;
2636 }
2637 EXPORT_SYMBOL(__xfrm_policy_check);
2638
2639 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2640 {
2641         struct net *net = dev_net(skb->dev);
2642         struct flowi fl;
2643         struct dst_entry *dst;
2644         int res = 1;
2645
2646         if (xfrm_decode_session(skb, &fl, family) < 0) {
2647                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2648                 return 0;
2649         }
2650
2651         skb_dst_force(skb);
2652
2653         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2654         if (IS_ERR(dst)) {
2655                 res = 0;
2656                 dst = NULL;
2657         }
2658         skb_dst_set(skb, dst);
2659         return res;
2660 }
2661 EXPORT_SYMBOL(__xfrm_route_forward);
2662
2663 /* Optimize later using cookies and generation ids. */
2664
2665 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2666 {
2667         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2668          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2669          * get validated by dst_ops->check on every use.  We do this
2670          * because when a normal route referenced by an XFRM dst is
2671          * obsoleted we do not go looking around for all parent
2672          * referencing XFRM dsts so that we can invalidate them.  It
2673          * is just too much work.  Instead we make the checks here on
2674          * every use.  For example:
2675          *
2676          *      XFRM dst A --> IPv4 dst X
2677          *
2678          * X is the "xdst->route" of A (X is also the "dst->path" of A
2679          * in this example).  If X is marked obsolete, "A" will not
2680          * notice.  That's what we are validating here via the
2681          * stale_bundle() check.
2682          *
2683          * When a policy's bundle is pruned, we dst_free() the XFRM
2684          * dst which causes it's ->obsolete field to be set to
2685          * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2686          * this, we want to force a new route lookup.
2687          */
2688         if (dst->obsolete < 0 && !stale_bundle(dst))
2689                 return dst;
2690
2691         return NULL;
2692 }
2693
2694 static int stale_bundle(struct dst_entry *dst)
2695 {
2696         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2697 }
2698
2699 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2700 {
2701         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2702                 dst->dev = dev_net(dev)->loopback_dev;
2703                 dev_hold(dst->dev);
2704                 dev_put(dev);
2705         }
2706 }
2707 EXPORT_SYMBOL(xfrm_dst_ifdown);
2708
2709 static void xfrm_link_failure(struct sk_buff *skb)
2710 {
2711         /* Impossible. Such dst must be popped before reaches point of failure. */
2712 }
2713
2714 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2715 {
2716         if (dst) {
2717                 if (dst->obsolete) {
2718                         dst_release(dst);
2719                         dst = NULL;
2720                 }
2721         }
2722         return dst;
2723 }
2724
2725 void xfrm_garbage_collect(struct net *net)
2726 {
2727         flow_cache_flush(net);
2728 }
2729 EXPORT_SYMBOL(xfrm_garbage_collect);
2730
2731 void xfrm_garbage_collect_deferred(struct net *net)
2732 {
2733         flow_cache_flush_deferred(net);
2734 }
2735 EXPORT_SYMBOL(xfrm_garbage_collect_deferred);
2736
2737 static void xfrm_init_pmtu(struct dst_entry *dst)
2738 {
2739         do {
2740                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2741                 u32 pmtu, route_mtu_cached;
2742
2743                 pmtu = dst_mtu(dst->child);
2744                 xdst->child_mtu_cached = pmtu;
2745
2746                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2747
2748                 route_mtu_cached = dst_mtu(xdst->route);
2749                 xdst->route_mtu_cached = route_mtu_cached;
2750
2751                 if (pmtu > route_mtu_cached)
2752                         pmtu = route_mtu_cached;
2753
2754                 dst_metric_set(dst, RTAX_MTU, pmtu);
2755         } while ((dst = dst->next));
2756 }
2757
2758 /* Check that the bundle accepts the flow and its components are
2759  * still valid.
2760  */
2761
2762 static int xfrm_bundle_ok(struct xfrm_dst *first)
2763 {
2764         struct dst_entry *dst = &first->u.dst;
2765         struct xfrm_dst *last;
2766         u32 mtu;
2767
2768         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2769             (dst->dev && !netif_running(dst->dev)))
2770                 return 0;
2771
2772         if (dst->flags & DST_XFRM_QUEUE)
2773                 return 1;
2774
2775         last = NULL;
2776
2777         do {
2778                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2779
2780                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2781                         return 0;
2782                 if (xdst->xfrm_genid != dst->xfrm->genid)
2783                         return 0;
2784                 if (xdst->num_pols > 0 &&
2785                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2786                         return 0;
2787
2788                 mtu = dst_mtu(dst->child);
2789                 if (xdst->child_mtu_cached != mtu) {
2790                         last = xdst;
2791                         xdst->child_mtu_cached = mtu;
2792                 }
2793
2794                 if (!dst_check(xdst->route, xdst->route_cookie))
2795                         return 0;
2796                 mtu = dst_mtu(xdst->route);
2797                 if (xdst->route_mtu_cached != mtu) {
2798                         last = xdst;
2799                         xdst->route_mtu_cached = mtu;
2800                 }
2801
2802                 dst = dst->child;
2803         } while (dst->xfrm);
2804
2805         if (likely(!last))
2806                 return 1;
2807
2808         mtu = last->child_mtu_cached;
2809         for (;;) {
2810                 dst = &last->u.dst;
2811
2812                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2813                 if (mtu > last->route_mtu_cached)
2814                         mtu = last->route_mtu_cached;
2815                 dst_metric_set(dst, RTAX_MTU, mtu);
2816
2817                 if (last == first)
2818                         break;
2819
2820                 last = (struct xfrm_dst *)last->u.dst.next;
2821                 last->child_mtu_cached = mtu;
2822         }
2823
2824         return 1;
2825 }
2826
2827 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2828 {
2829         return dst_metric_advmss(dst->path);
2830 }
2831
2832 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2833 {
2834         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2835
2836         return mtu ? : dst_mtu(dst->path);
2837 }
2838
2839 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2840                                         const void *daddr)
2841 {
2842         const struct dst_entry *path = dst->path;
2843
2844         for (; dst != path; dst = dst->child) {
2845                 const struct xfrm_state *xfrm = dst->xfrm;
2846
2847                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2848                         continue;
2849                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2850                         daddr = xfrm->coaddr;
2851                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2852                         daddr = &xfrm->id.daddr;
2853         }
2854         return daddr;
2855 }
2856
2857 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2858                                            struct sk_buff *skb,
2859                                            const void *daddr)
2860 {
2861         const struct dst_entry *path = dst->path;
2862
2863         if (!skb)
2864                 daddr = xfrm_get_dst_nexthop(dst, daddr);
2865         return path->ops->neigh_lookup(path, skb, daddr);
2866 }
2867
2868 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2869 {
2870         const struct dst_entry *path = dst->path;
2871
2872         daddr = xfrm_get_dst_nexthop(dst, daddr);
2873         path->ops->confirm_neigh(path, daddr);
2874 }
2875
2876 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2877 {
2878         int err = 0;
2879
2880         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2881                 return -EAFNOSUPPORT;
2882
2883         spin_lock(&xfrm_policy_afinfo_lock);
2884         if (unlikely(xfrm_policy_afinfo[family] != NULL))
2885                 err = -EEXIST;
2886         else {
2887                 struct dst_ops *dst_ops = afinfo->dst_ops;
2888                 if (likely(dst_ops->kmem_cachep == NULL))
2889                         dst_ops->kmem_cachep = xfrm_dst_cache;
2890                 if (likely(dst_ops->check == NULL))
2891                         dst_ops->check = xfrm_dst_check;
2892                 if (likely(dst_ops->default_advmss == NULL))
2893                         dst_ops->default_advmss = xfrm_default_advmss;
2894                 if (likely(dst_ops->mtu == NULL))
2895                         dst_ops->mtu = xfrm_mtu;
2896                 if (likely(dst_ops->negative_advice == NULL))
2897                         dst_ops->negative_advice = xfrm_negative_advice;
2898                 if (likely(dst_ops->link_failure == NULL))
2899                         dst_ops->link_failure = xfrm_link_failure;
2900                 if (likely(dst_ops->neigh_lookup == NULL))
2901                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2902                 if (likely(!dst_ops->confirm_neigh))
2903                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
2904                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2905         }
2906         spin_unlock(&xfrm_policy_afinfo_lock);
2907
2908         return err;
2909 }
2910 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2911
2912 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2913 {
2914         struct dst_ops *dst_ops = afinfo->dst_ops;
2915         int i;
2916
2917         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2918                 if (xfrm_policy_afinfo[i] != afinfo)
2919                         continue;
2920                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2921                 break;
2922         }
2923
2924         synchronize_rcu();
2925
2926         dst_ops->kmem_cachep = NULL;
2927         dst_ops->check = NULL;
2928         dst_ops->negative_advice = NULL;
2929         dst_ops->link_failure = NULL;
2930 }
2931 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2932
2933 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2934 {
2935         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2936
2937         switch (event) {
2938         case NETDEV_DOWN:
2939                 xfrm_garbage_collect(dev_net(dev));
2940         }
2941         return NOTIFY_DONE;
2942 }
2943
2944 static struct notifier_block xfrm_dev_notifier = {
2945         .notifier_call  = xfrm_dev_event,
2946 };
2947
2948 #ifdef CONFIG_XFRM_STATISTICS
2949 static int __net_init xfrm_statistics_init(struct net *net)
2950 {
2951         int rv;
2952         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2953         if (!net->mib.xfrm_statistics)
2954                 return -ENOMEM;
2955         rv = xfrm_proc_init(net);
2956         if (rv < 0)
2957                 free_percpu(net->mib.xfrm_statistics);
2958         return rv;
2959 }
2960
2961 static void xfrm_statistics_fini(struct net *net)
2962 {
2963         xfrm_proc_fini(net);
2964         free_percpu(net->mib.xfrm_statistics);
2965 }
2966 #else
2967 static int __net_init xfrm_statistics_init(struct net *net)
2968 {
2969         return 0;
2970 }
2971
2972 static void xfrm_statistics_fini(struct net *net)
2973 {
2974 }
2975 #endif
2976
2977 static int __net_init xfrm_policy_init(struct net *net)
2978 {
2979         unsigned int hmask, sz;
2980         int dir;
2981
2982         if (net_eq(net, &init_net))
2983                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2984                                            sizeof(struct xfrm_dst),
2985                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2986                                            NULL);
2987
2988         hmask = 8 - 1;
2989         sz = (hmask+1) * sizeof(struct hlist_head);
2990
2991         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2992         if (!net->xfrm.policy_byidx)
2993                 goto out_byidx;
2994         net->xfrm.policy_idx_hmask = hmask;
2995
2996         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2997                 struct xfrm_policy_hash *htab;
2998
2999                 net->xfrm.policy_count[dir] = 0;
3000                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
3001                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
3002
3003                 htab = &net->xfrm.policy_bydst[dir];
3004                 htab->table = xfrm_hash_alloc(sz);
3005                 if (!htab->table)
3006                         goto out_bydst;
3007                 htab->hmask = hmask;
3008                 htab->dbits4 = 32;
3009                 htab->sbits4 = 32;
3010                 htab->dbits6 = 128;
3011                 htab->sbits6 = 128;
3012         }
3013         net->xfrm.policy_hthresh.lbits4 = 32;
3014         net->xfrm.policy_hthresh.rbits4 = 32;
3015         net->xfrm.policy_hthresh.lbits6 = 128;
3016         net->xfrm.policy_hthresh.rbits6 = 128;
3017
3018         seqlock_init(&net->xfrm.policy_hthresh.lock);
3019
3020         INIT_LIST_HEAD(&net->xfrm.policy_all);
3021         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
3022         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
3023         if (net_eq(net, &init_net))
3024                 register_netdevice_notifier(&xfrm_dev_notifier);
3025         return 0;
3026
3027 out_bydst:
3028         for (dir--; dir >= 0; dir--) {
3029                 struct xfrm_policy_hash *htab;
3030
3031                 htab = &net->xfrm.policy_bydst[dir];
3032                 xfrm_hash_free(htab->table, sz);
3033         }
3034         xfrm_hash_free(net->xfrm.policy_byidx, sz);
3035 out_byidx:
3036         return -ENOMEM;
3037 }
3038
3039 static void xfrm_policy_fini(struct net *net)
3040 {
3041         unsigned int sz;
3042         int dir;
3043
3044         flush_work(&net->xfrm.policy_hash_work);
3045 #ifdef CONFIG_XFRM_SUB_POLICY
3046         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
3047 #endif
3048         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
3049
3050         WARN_ON(!list_empty(&net->xfrm.policy_all));
3051
3052         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
3053                 struct xfrm_policy_hash *htab;
3054
3055                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
3056
3057                 htab = &net->xfrm.policy_bydst[dir];
3058                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
3059                 WARN_ON(!hlist_empty(htab->table));
3060                 xfrm_hash_free(htab->table, sz);
3061         }
3062
3063         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
3064         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
3065         xfrm_hash_free(net->xfrm.policy_byidx, sz);
3066 }
3067
3068 static int __net_init xfrm_net_init(struct net *net)
3069 {
3070         int rv;
3071
3072         rv = xfrm_statistics_init(net);
3073         if (rv < 0)
3074                 goto out_statistics;
3075         rv = xfrm_state_init(net);
3076         if (rv < 0)
3077                 goto out_state;
3078         rv = xfrm_policy_init(net);
3079         if (rv < 0)
3080                 goto out_policy;
3081         rv = xfrm_sysctl_init(net);
3082         if (rv < 0)
3083                 goto out_sysctl;
3084         rv = flow_cache_init(net);
3085         if (rv < 0)
3086                 goto out;
3087
3088         /* Initialize the per-net locks here */
3089         spin_lock_init(&net->xfrm.xfrm_state_lock);
3090         spin_lock_init(&net->xfrm.xfrm_policy_lock);
3091         mutex_init(&net->xfrm.xfrm_cfg_mutex);
3092
3093         return 0;
3094
3095 out:
3096         xfrm_sysctl_fini(net);
3097 out_sysctl:
3098         xfrm_policy_fini(net);
3099 out_policy:
3100         xfrm_state_fini(net);
3101 out_state:
3102         xfrm_statistics_fini(net);
3103 out_statistics:
3104         return rv;
3105 }
3106
3107 static void __net_exit xfrm_net_exit(struct net *net)
3108 {
3109         flow_cache_fini(net);
3110         xfrm_sysctl_fini(net);
3111         xfrm_policy_fini(net);
3112         xfrm_state_fini(net);
3113         xfrm_statistics_fini(net);
3114 }
3115
3116 static struct pernet_operations __net_initdata xfrm_net_ops = {
3117         .init = xfrm_net_init,
3118         .exit = xfrm_net_exit,
3119 };
3120
3121 void __init xfrm_init(void)
3122 {
3123         flow_cache_hp_init();
3124         register_pernet_subsys(&xfrm_net_ops);
3125         seqcount_init(&xfrm_policy_hash_generation);
3126         xfrm_input_init();
3127 }
3128
3129 #ifdef CONFIG_AUDITSYSCALL
3130 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3131                                          struct audit_buffer *audit_buf)
3132 {
3133         struct xfrm_sec_ctx *ctx = xp->security;
3134         struct xfrm_selector *sel = &xp->selector;
3135
3136         if (ctx)
3137                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3138                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3139
3140         switch (sel->family) {
3141         case AF_INET:
3142                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3143                 if (sel->prefixlen_s != 32)
3144                         audit_log_format(audit_buf, " src_prefixlen=%d",
3145                                          sel->prefixlen_s);
3146                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3147                 if (sel->prefixlen_d != 32)
3148                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3149                                          sel->prefixlen_d);
3150                 break;
3151         case AF_INET6:
3152                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3153                 if (sel->prefixlen_s != 128)
3154                         audit_log_format(audit_buf, " src_prefixlen=%d",
3155                                          sel->prefixlen_s);
3156                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3157                 if (sel->prefixlen_d != 128)
3158                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3159                                          sel->prefixlen_d);
3160                 break;
3161         }
3162 }
3163
3164 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3165 {
3166         struct audit_buffer *audit_buf;
3167
3168         audit_buf = xfrm_audit_start("SPD-add");
3169         if (audit_buf == NULL)
3170                 return;
3171         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3172         audit_log_format(audit_buf, " res=%u", result);
3173         xfrm_audit_common_policyinfo(xp, audit_buf);
3174         audit_log_end(audit_buf);
3175 }
3176 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3177
3178 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3179                               bool task_valid)
3180 {
3181         struct audit_buffer *audit_buf;
3182
3183         audit_buf = xfrm_audit_start("SPD-delete");
3184         if (audit_buf == NULL)
3185                 return;
3186         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3187         audit_log_format(audit_buf, " res=%u", result);
3188         xfrm_audit_common_policyinfo(xp, audit_buf);
3189         audit_log_end(audit_buf);
3190 }
3191 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3192 #endif
3193
3194 #ifdef CONFIG_XFRM_MIGRATE
3195 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3196                                         const struct xfrm_selector *sel_tgt)
3197 {
3198         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3199                 if (sel_tgt->family == sel_cmp->family &&
3200                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3201                                     sel_cmp->family) &&
3202                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3203                                     sel_cmp->family) &&
3204                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3205                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3206                         return true;
3207                 }
3208         } else {
3209                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3210                         return true;
3211                 }
3212         }
3213         return false;
3214 }
3215
3216 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3217                                                     u8 dir, u8 type, struct net *net)
3218 {
3219         struct xfrm_policy *pol, *ret = NULL;
3220         struct hlist_head *chain;
3221         u32 priority = ~0U;
3222
3223         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3224         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3225         hlist_for_each_entry(pol, chain, bydst) {
3226                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3227                     pol->type == type) {
3228                         ret = pol;
3229                         priority = ret->priority;
3230                         break;
3231                 }
3232         }
3233         chain = &net->xfrm.policy_inexact[dir];
3234         hlist_for_each_entry(pol, chain, bydst) {
3235                 if ((pol->priority >= priority) && ret)
3236                         break;
3237
3238                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3239                     pol->type == type) {
3240                         ret = pol;
3241                         break;
3242                 }
3243         }
3244
3245         xfrm_pol_hold(ret);
3246
3247         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3248
3249         return ret;
3250 }
3251
3252 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3253 {
3254         int match = 0;
3255
3256         if (t->mode == m->mode && t->id.proto == m->proto &&
3257             (m->reqid == 0 || t->reqid == m->reqid)) {
3258                 switch (t->mode) {
3259                 case XFRM_MODE_TUNNEL:
3260                 case XFRM_MODE_BEET:
3261                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3262                                             m->old_family) &&
3263                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3264                                             m->old_family)) {
3265                                 match = 1;
3266                         }
3267                         break;
3268                 case XFRM_MODE_TRANSPORT:
3269                         /* in case of transport mode, template does not store
3270                            any IP addresses, hence we just compare mode and
3271                            protocol */
3272                         match = 1;
3273                         break;
3274                 default:
3275                         break;
3276                 }
3277         }
3278         return match;
3279 }
3280
3281 /* update endpoint address(es) of template(s) */
3282 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3283                                struct xfrm_migrate *m, int num_migrate)
3284 {
3285         struct xfrm_migrate *mp;
3286         int i, j, n = 0;
3287
3288         write_lock_bh(&pol->lock);
3289         if (unlikely(pol->walk.dead)) {
3290                 /* target policy has been deleted */
3291                 write_unlock_bh(&pol->lock);
3292                 return -ENOENT;
3293         }
3294
3295         for (i = 0; i < pol->xfrm_nr; i++) {
3296                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3297                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3298                                 continue;
3299                         n++;
3300                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3301                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3302                                 continue;
3303                         /* update endpoints */
3304                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3305                                sizeof(pol->xfrm_vec[i].id.daddr));
3306                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3307                                sizeof(pol->xfrm_vec[i].saddr));
3308                         pol->xfrm_vec[i].encap_family = mp->new_family;
3309                         /* flush bundles */
3310                         atomic_inc(&pol->genid);
3311                 }
3312         }
3313
3314         write_unlock_bh(&pol->lock);
3315
3316         if (!n)
3317                 return -ENODATA;
3318
3319         return 0;
3320 }
3321
3322 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3323 {
3324         int i, j;
3325
3326         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3327                 return -EINVAL;
3328
3329         for (i = 0; i < num_migrate; i++) {
3330                 if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3331                                     m[i].old_family) &&
3332                     xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3333                                     m[i].old_family))
3334                         return -EINVAL;
3335                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3336                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3337                         return -EINVAL;
3338
3339                 /* check if there is any duplicated entry */
3340                 for (j = i + 1; j < num_migrate; j++) {
3341                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3342                                     sizeof(m[i].old_daddr)) &&
3343                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3344                                     sizeof(m[i].old_saddr)) &&
3345                             m[i].proto == m[j].proto &&
3346                             m[i].mode == m[j].mode &&
3347                             m[i].reqid == m[j].reqid &&
3348                             m[i].old_family == m[j].old_family)
3349                                 return -EINVAL;
3350                 }
3351         }
3352
3353         return 0;
3354 }
3355
3356 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3357                  struct xfrm_migrate *m, int num_migrate,
3358                  struct xfrm_kmaddress *k, struct net *net)
3359 {
3360         int i, err, nx_cur = 0, nx_new = 0;
3361         struct xfrm_policy *pol = NULL;
3362         struct xfrm_state *x, *xc;
3363         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3364         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3365         struct xfrm_migrate *mp;
3366
3367         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3368                 goto out;
3369
3370         /* Stage 1 - find policy */
3371         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3372                 err = -ENOENT;
3373                 goto out;
3374         }
3375
3376         /* Stage 2 - find and update state(s) */
3377         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3378                 if ((x = xfrm_migrate_state_find(mp, net))) {
3379                         x_cur[nx_cur] = x;
3380                         nx_cur++;
3381                         if ((xc = xfrm_state_migrate(x, mp))) {
3382                                 x_new[nx_new] = xc;
3383                                 nx_new++;
3384                         } else {
3385                                 err = -ENODATA;
3386                                 goto restore_state;
3387                         }
3388                 }
3389         }
3390
3391         /* Stage 3 - update policy */
3392         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3393                 goto restore_state;
3394
3395         /* Stage 4 - delete old state(s) */
3396         if (nx_cur) {
3397                 xfrm_states_put(x_cur, nx_cur);
3398                 xfrm_states_delete(x_cur, nx_cur);
3399         }
3400
3401         /* Stage 5 - announce */
3402         km_migrate(sel, dir, type, m, num_migrate, k);
3403
3404         xfrm_pol_put(pol);
3405
3406         return 0;
3407 out:
3408         return err;
3409
3410 restore_state:
3411         if (pol)
3412                 xfrm_pol_put(pol);
3413         if (nx_cur)
3414                 xfrm_states_put(x_cur, nx_cur);
3415         if (nx_new)
3416                 xfrm_states_delete(x_new, nx_new);
3417
3418         return err;
3419 }
3420 EXPORT_SYMBOL(xfrm_migrate);
3421 #endif