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 __rcu *xfrm_policy_afinfo[NPROTO]
  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 struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 107 {
 108         struct xfrm_policy_afinfo *afinfo;
 109
 110         if (unlikely(family >= NPROTO))
 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 void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
 120 {
 121         rcu_read_unlock();
 122 }
 123
 124 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net,
 125                                                   int tos, int oif,
 126                                                   const xfrm_address_t *saddr,
 127                                                   const xfrm_address_t *daddr,
 128                                                   int family)
 129 {
 130         struct xfrm_policy_afinfo *afinfo;
 131         struct dst_entry *dst;
 132
 133         afinfo = xfrm_policy_get_afinfo(family);
 134         if (unlikely(afinfo == NULL))
 135                 return ERR_PTR(-EAFNOSUPPORT);
 136
 137         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr);
 138
 139         xfrm_policy_put_afinfo(afinfo);
 140
 141         return dst;
 142 }
 143
 144 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 145                                                 int tos, int oif,
 146                                                 xfrm_address_t *prev_saddr,
 147                                                 xfrm_address_t *prev_daddr,
 148                                                 int family)
 149 {
 150         struct net *net = xs_net(x);
 151         xfrm_address_t *saddr = &x->props.saddr;
 152         xfrm_address_t *daddr = &x->id.daddr;
 153         struct dst_entry *dst;
 154
 155         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 156                 saddr = x->coaddr;
 157                 daddr = prev_daddr;
 158         }
 159         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 160                 saddr = prev_saddr;
 161                 daddr = x->coaddr;
 162         }
 163
 164         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family);
 165
 166         if (!IS_ERR(dst)) {
 167                 if (prev_saddr != saddr)
 168                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 169                 if (prev_daddr != daddr)
 170                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 171         }
 172
 173         return dst;
 174 }
 175
 176 static inline unsigned long make_jiffies(long secs)
 177 {
 178         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 179                 return MAX_SCHEDULE_TIMEOUT-1;
 180         else
 181                 return secs*HZ;
 182 }
 183
 184 static void xfrm_policy_timer(unsigned long data)
 185 {
 186         struct xfrm_policy *xp = (struct xfrm_policy *)data;
 187         unsigned long now = get_seconds();
 188         long next = LONG_MAX;
 189         int warn = 0;
 190         int dir;
 191
 192         read_lock(&xp->lock);
 193
 194         if (unlikely(xp->walk.dead))
 195                 goto out;
 196
 197         dir = xfrm_policy_id2dir(xp->index);
 198
 199         if (xp->lft.hard_add_expires_seconds) {
 200                 long tmo = xp->lft.hard_add_expires_seconds +
 201                         xp->curlft.add_time - now;
 202                 if (tmo <= 0)
 203                         goto expired;
 204                 if (tmo < next)
 205                         next = tmo;
 206         }
 207         if (xp->lft.hard_use_expires_seconds) {
 208                 long tmo = xp->lft.hard_use_expires_seconds +
 209                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 210                 if (tmo <= 0)
 211                         goto expired;
 212                 if (tmo < next)
 213                         next = tmo;
 214         }
 215         if (xp->lft.soft_add_expires_seconds) {
 216                 long tmo = xp->lft.soft_add_expires_seconds +
 217                         xp->curlft.add_time - now;
 218                 if (tmo <= 0) {
 219                         warn = 1;
 220                         tmo = XFRM_KM_TIMEOUT;
 221                 }
 222                 if (tmo < next)
 223                         next = tmo;
 224         }
 225         if (xp->lft.soft_use_expires_seconds) {
 226                 long tmo = xp->lft.soft_use_expires_seconds +
 227                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 228                 if (tmo <= 0) {
 229                         warn = 1;
 230                         tmo = XFRM_KM_TIMEOUT;
 231                 }
 232                 if (tmo < next)
 233                         next = tmo;
 234         }
 235
 236         if (warn)
 237                 km_policy_expired(xp, dir, 0, 0);
 238         if (next != LONG_MAX &&
 239             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 240                 xfrm_pol_hold(xp);
 241
 242 out:
 243         read_unlock(&xp->lock);
 244         xfrm_pol_put(xp);
 245         return;
 246
 247 expired:
 248         read_unlock(&xp->lock);
 249         if (!xfrm_policy_delete(xp, dir))
 250                 km_policy_expired(xp, dir, 1, 0);
 251         xfrm_pol_put(xp);
 252 }
 253
 254 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
 255 {
 256         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 257
 258         if (unlikely(pol->walk.dead))
 259                 flo = NULL;
 260         else
 261                 xfrm_pol_hold(pol);
 262
 263         return flo;
 264 }
 265
 266 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
 267 {
 268         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 269
 270         return !pol->walk.dead;
 271 }
 272
 273 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
 274 {
 275         xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
 276 }
 277
 278 static const struct flow_cache_ops xfrm_policy_fc_ops = {
 279         .get = xfrm_policy_flo_get,
 280         .check = xfrm_policy_flo_check,
 281         .delete = xfrm_policy_flo_delete,
 282 };
 283
 284 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 285  * SPD calls.
 286  */
 287
 288 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 289 {
 290         struct xfrm_policy *policy;
 291
 292         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 293
 294         if (policy) {
 295                 write_pnet(&policy->xp_net, net);
 296                 INIT_LIST_HEAD(&policy->walk.all);
 297                 INIT_HLIST_NODE(&policy->bydst);
 298                 INIT_HLIST_NODE(&policy->byidx);
 299                 rwlock_init(&policy->lock);
 300                 atomic_set(&policy->refcnt, 1);
 301                 skb_queue_head_init(&policy->polq.hold_queue);
 302                 setup_timer(&policy->timer, xfrm_policy_timer,
 303                                 (unsigned long)policy);
 304                 setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
 305                             (unsigned long)policy);
 306                 policy->flo.ops = &xfrm_policy_fc_ops;
 307         }
 308         return policy;
 309 }
 310 EXPORT_SYMBOL(xfrm_policy_alloc);
 311
 312 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 313 {
 314         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 315
 316         security_xfrm_policy_free(policy->security);
 317         kfree(policy);
 318 }
 319
 320 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 321
 322 void xfrm_policy_destroy(struct xfrm_policy *policy)
 323 {
 324         BUG_ON(!policy->walk.dead);
 325
 326         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 327                 BUG();
 328
 329         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 330 }
 331 EXPORT_SYMBOL(xfrm_policy_destroy);
 332
 333 /* Rule must be locked. Release descentant resources, announce
 334  * entry dead. The rule must be unlinked from lists to the moment.
 335  */
 336
 337 static void xfrm_policy_kill(struct xfrm_policy *policy)
 338 {
 339         policy->walk.dead = 1;
 340
 341         atomic_inc(&policy->genid);
 342
 343         if (del_timer(&policy->polq.hold_timer))
 344                 xfrm_pol_put(policy);
 345         skb_queue_purge(&policy->polq.hold_queue);
 346
 347         if (del_timer(&policy->timer))
 348                 xfrm_pol_put(policy);
 349
 350         xfrm_pol_put(policy);
 351 }
 352
 353 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 354
 355 static inline unsigned int idx_hash(struct net *net, u32 index)
 356 {
 357         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 358 }
 359
 360 /* calculate policy hash thresholds */
 361 static void __get_hash_thresh(struct net *net,
 362                               unsigned short family, int dir,
 363                               u8 *dbits, u8 *sbits)
 364 {
 365         switch (family) {
 366         case AF_INET:
 367                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 368                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 369                 break;
 370
 371         case AF_INET6:
 372                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 373                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 374                 break;
 375
 376         default:
 377                 *dbits = 0;
 378                 *sbits = 0;
 379         }
 380 }
 381
 382 static struct hlist_head *policy_hash_bysel(struct net *net,
 383                                             const struct xfrm_selector *sel,
 384                                             unsigned short family, int dir)
 385 {
 386         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 387         unsigned int hash;
 388         u8 dbits;
 389         u8 sbits;
 390
 391         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 392         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 393
 394         if (hash == hmask + 1)
 395                 return &net->xfrm.policy_inexact[dir];
 396
 397         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 398                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 399 }
 400
 401 static struct hlist_head *policy_hash_direct(struct net *net,
 402                                              const xfrm_address_t *daddr,
 403                                              const xfrm_address_t *saddr,
 404                                              unsigned short family, int dir)
 405 {
 406         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 407         unsigned int hash;
 408         u8 dbits;
 409         u8 sbits;
 410
 411         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 412         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 413
 414         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 415                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 416 }
 417
 418 static void xfrm_dst_hash_transfer(struct net *net,
 419                                    struct hlist_head *list,
 420                                    struct hlist_head *ndsttable,
 421                                    unsigned int nhashmask,
 422                                    int dir)
 423 {
 424         struct hlist_node *tmp, *entry0 = NULL;
 425         struct xfrm_policy *pol;
 426         unsigned int h0 = 0;
 427         u8 dbits;
 428         u8 sbits;
 429
 430 redo:
 431         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 432                 unsigned int h;
 433
 434                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 435                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 436                                 pol->family, nhashmask, dbits, sbits);
 437                 if (!entry0) {
 438                         hlist_del_rcu(&pol->bydst);
 439                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 440                         h0 = h;
 441                 } else {
 442                         if (h != h0)
 443                                 continue;
 444                         hlist_del_rcu(&pol->bydst);
 445                         hlist_add_behind_rcu(&pol->bydst, entry0);
 446                 }
 447                 entry0 = &pol->bydst;
 448         }
 449         if (!hlist_empty(list)) {
 450                 entry0 = NULL;
 451                 goto redo;
 452         }
 453 }
 454
 455 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 456                                    struct hlist_head *nidxtable,
 457                                    unsigned int nhashmask)
 458 {
 459         struct hlist_node *tmp;
 460         struct xfrm_policy *pol;
 461
 462         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 463                 unsigned int h;
 464
 465                 h = __idx_hash(pol->index, nhashmask);
 466                 hlist_add_head(&pol->byidx, nidxtable+h);
 467         }
 468 }
 469
 470 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 471 {
 472         return ((old_hmask + 1) << 1) - 1;
 473 }
 474
 475 static void xfrm_bydst_resize(struct net *net, int dir)
 476 {
 477         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 478         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 479         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 480         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 481         struct hlist_head *odst;
 482         int i;
 483
 484         if (!ndst)
 485                 return;
 486
 487         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 488         write_seqcount_begin(&xfrm_policy_hash_generation);
 489
 490         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 491                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 492
 493         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 494                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 495
 496         for (i = hmask; i >= 0; i--)
 497                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 498
 499         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 500         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 501
 502         write_seqcount_end(&xfrm_policy_hash_generation);
 503         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 504
 505         synchronize_rcu();
 506
 507         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 508 }
 509
 510 static void xfrm_byidx_resize(struct net *net, int total)
 511 {
 512         unsigned int hmask = net->xfrm.policy_idx_hmask;
 513         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 514         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 515         struct hlist_head *oidx = net->xfrm.policy_byidx;
 516         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 517         int i;
 518
 519         if (!nidx)
 520                 return;
 521
 522         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 523
 524         for (i = hmask; i >= 0; i--)
 525                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 526
 527         net->xfrm.policy_byidx = nidx;
 528         net->xfrm.policy_idx_hmask = nhashmask;
 529
 530         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 531
 532         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 533 }
 534
 535 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 536 {
 537         unsigned int cnt = net->xfrm.policy_count[dir];
 538         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 539
 540         if (total)
 541                 *total += cnt;
 542
 543         if ((hmask + 1) < xfrm_policy_hashmax &&
 544             cnt > hmask)
 545                 return 1;
 546
 547         return 0;
 548 }
 549
 550 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 551 {
 552         unsigned int hmask = net->xfrm.policy_idx_hmask;
 553
 554         if ((hmask + 1) < xfrm_policy_hashmax &&
 555             total > hmask)
 556                 return 1;
 557
 558         return 0;
 559 }
 560
 561 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 562 {
 563         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 564         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 565         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 566         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 567         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 568         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 569         si->spdhcnt = net->xfrm.policy_idx_hmask;
 570         si->spdhmcnt = xfrm_policy_hashmax;
 571 }
 572 EXPORT_SYMBOL(xfrm_spd_getinfo);
 573
 574 static DEFINE_MUTEX(hash_resize_mutex);
 575 static void xfrm_hash_resize(struct work_struct *work)
 576 {
 577         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 578         int dir, total;
 579
 580         mutex_lock(&hash_resize_mutex);
 581
 582         total = 0;
 583         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 584                 if (xfrm_bydst_should_resize(net, dir, &total))
 585                         xfrm_bydst_resize(net, dir);
 586         }
 587         if (xfrm_byidx_should_resize(net, total))
 588                 xfrm_byidx_resize(net, total);
 589
 590         mutex_unlock(&hash_resize_mutex);
 591 }
 592
 593 static void xfrm_hash_rebuild(struct work_struct *work)
 594 {
 595         struct net *net = container_of(work, struct net,
 596                                        xfrm.policy_hthresh.work);
 597         unsigned int hmask;
 598         struct xfrm_policy *pol;
 599         struct xfrm_policy *policy;
 600         struct hlist_head *chain;
 601         struct hlist_head *odst;
 602         struct hlist_node *newpos;
 603         int i;
 604         int dir;
 605         unsigned seq;
 606         u8 lbits4, rbits4, lbits6, rbits6;
 607
 608         mutex_lock(&hash_resize_mutex);
 609
 610         /* read selector prefixlen thresholds */
 611         do {
 612                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
 613
 614                 lbits4 = net->xfrm.policy_hthresh.lbits4;
 615                 rbits4 = net->xfrm.policy_hthresh.rbits4;
 616                 lbits6 = net->xfrm.policy_hthresh.lbits6;
 617                 rbits6 = net->xfrm.policy_hthresh.rbits6;
 618         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
 619
 620         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 621
 622         /* reset the bydst and inexact table in all directions */
 623         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 624                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
 625                 hmask = net->xfrm.policy_bydst[dir].hmask;
 626                 odst = net->xfrm.policy_bydst[dir].table;
 627                 for (i = hmask; i >= 0; i--)
 628                         INIT_HLIST_HEAD(odst + i);
 629                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
 630                         /* dir out => dst = remote, src = local */
 631                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
 632                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
 633                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
 634                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
 635                 } else {
 636                         /* dir in/fwd => dst = local, src = remote */
 637                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
 638                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
 639                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
 640                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
 641                 }
 642         }
 643
 644         /* re-insert all policies by order of creation */
 645         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 646                 if (xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
 647                         /* skip socket policies */
 648                         continue;
 649                 }
 650                 newpos = NULL;
 651                 chain = policy_hash_bysel(net, &policy->selector,
 652                                           policy->family,
 653                                           xfrm_policy_id2dir(policy->index));
 654                 hlist_for_each_entry(pol, chain, bydst) {
 655                         if (policy->priority >= pol->priority)
 656                                 newpos = &pol->bydst;
 657                         else
 658                                 break;
 659                 }
 660                 if (newpos)
 661                         hlist_add_behind(&policy->bydst, newpos);
 662                 else
 663                         hlist_add_head(&policy->bydst, chain);
 664         }
 665
 666         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 667
 668         mutex_unlock(&hash_resize_mutex);
 669 }
 670
 671 void xfrm_policy_hash_rebuild(struct net *net)
 672 {
 673         schedule_work(&net->xfrm.policy_hthresh.work);
 674 }
 675 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
 676
 677 /* Generate new index... KAME seems to generate them ordered by cost
 678  * of an absolute inpredictability of ordering of rules. This will not pass. */
 679 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
 680 {
 681         static u32 idx_generator;
 682
 683         for (;;) {
 684                 struct hlist_head *list;
 685                 struct xfrm_policy *p;
 686                 u32 idx;
 687                 int found;
 688
 689                 if (!index) {
 690                         idx = (idx_generator | dir);
 691                         idx_generator += 8;
 692                 } else {
 693                         idx = index;
 694                         index = 0;
 695                 }
 696
 697                 if (idx == 0)
 698                         idx = 8;
 699                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 700                 found = 0;
 701                 hlist_for_each_entry(p, list, byidx) {
 702                         if (p->index == idx) {
 703                                 found = 1;
 704                                 break;
 705                         }
 706                 }
 707                 if (!found)
 708                         return idx;
 709         }
 710 }
 711
 712 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 713 {
 714         u32 *p1 = (u32 *) s1;
 715         u32 *p2 = (u32 *) s2;
 716         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 717         int i;
 718
 719         for (i = 0; i < len; i++) {
 720                 if (p1[i] != p2[i])
 721                         return 1;
 722         }
 723
 724         return 0;
 725 }
 726
 727 static void xfrm_policy_requeue(struct xfrm_policy *old,
 728                                 struct xfrm_policy *new)
 729 {
 730         struct xfrm_policy_queue *pq = &old->polq;
 731         struct sk_buff_head list;
 732
 733         if (skb_queue_empty(&pq->hold_queue))
 734                 return;
 735
 736         __skb_queue_head_init(&list);
 737
 738         spin_lock_bh(&pq->hold_queue.lock);
 739         skb_queue_splice_init(&pq->hold_queue, &list);
 740         if (del_timer(&pq->hold_timer))
 741                 xfrm_pol_put(old);
 742         spin_unlock_bh(&pq->hold_queue.lock);
 743
 744         pq = &new->polq;
 745
 746         spin_lock_bh(&pq->hold_queue.lock);
 747         skb_queue_splice(&list, &pq->hold_queue);
 748         pq->timeout = XFRM_QUEUE_TMO_MIN;
 749         if (!mod_timer(&pq->hold_timer, jiffies))
 750                 xfrm_pol_hold(new);
 751         spin_unlock_bh(&pq->hold_queue.lock);
 752 }
 753
 754 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
 755                                    struct xfrm_policy *pol)
 756 {
 757         u32 mark = policy->mark.v & policy->mark.m;
 758
 759         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
 760                 return true;
 761
 762         if ((mark & pol->mark.m) == pol->mark.v &&
 763             policy->priority == pol->priority)
 764                 return true;
 765
 766         return false;
 767 }
 768
 769 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 770 {
 771         struct net *net = xp_net(policy);
 772         struct xfrm_policy *pol;
 773         struct xfrm_policy *delpol;
 774         struct hlist_head *chain;
 775         struct hlist_node *newpos;
 776
 777         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 778         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 779         delpol = NULL;
 780         newpos = NULL;
 781         hlist_for_each_entry(pol, chain, bydst) {
 782                 if (pol->type == policy->type &&
 783                     !selector_cmp(&pol->selector, &policy->selector) &&
 784                     xfrm_policy_mark_match(policy, pol) &&
 785                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 786                     !WARN_ON(delpol)) {
 787                         if (excl) {
 788                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 789                                 return -EEXIST;
 790                         }
 791                         delpol = pol;
 792                         if (policy->priority > pol->priority)
 793                                 continue;
 794                 } else if (policy->priority >= pol->priority) {
 795                         newpos = &pol->bydst;
 796                         continue;
 797                 }
 798                 if (delpol)
 799                         break;
 800         }
 801         if (newpos)
 802                 hlist_add_behind(&policy->bydst, newpos);
 803         else
 804                 hlist_add_head(&policy->bydst, chain);
 805         __xfrm_policy_link(policy, dir);
 806         atomic_inc(&net->xfrm.flow_cache_genid);
 807
 808         /* After previous checking, family can either be AF_INET or AF_INET6 */
 809         if (policy->family == AF_INET)
 810                 rt_genid_bump_ipv4(net);
 811         else
 812                 rt_genid_bump_ipv6(net);
 813
 814         if (delpol) {
 815                 xfrm_policy_requeue(delpol, policy);
 816                 __xfrm_policy_unlink(delpol, dir);
 817         }
 818         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
 819         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 820         policy->curlft.add_time = get_seconds();
 821         policy->curlft.use_time = 0;
 822         if (!mod_timer(&policy->timer, jiffies + HZ))
 823                 xfrm_pol_hold(policy);
 824         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 825
 826         if (delpol)
 827                 xfrm_policy_kill(delpol);
 828         else if (xfrm_bydst_should_resize(net, dir, NULL))
 829                 schedule_work(&net->xfrm.policy_hash_work);
 830
 831         return 0;
 832 }
 833 EXPORT_SYMBOL(xfrm_policy_insert);
 834
 835 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
 836                                           int dir, struct xfrm_selector *sel,
 837                                           struct xfrm_sec_ctx *ctx, int delete,
 838                                           int *err)
 839 {
 840         struct xfrm_policy *pol, *ret;
 841         struct hlist_head *chain;
 842
 843         *err = 0;
 844         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 845         chain = policy_hash_bysel(net, sel, sel->family, dir);
 846         ret = NULL;
 847         hlist_for_each_entry(pol, chain, bydst) {
 848                 if (pol->type == type &&
 849                     (mark & pol->mark.m) == pol->mark.v &&
 850                     !selector_cmp(sel, &pol->selector) &&
 851                     xfrm_sec_ctx_match(ctx, pol->security)) {
 852                         xfrm_pol_hold(pol);
 853                         if (delete) {
 854                                 *err = security_xfrm_policy_delete(
 855                                                                 pol->security);
 856                                 if (*err) {
 857                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 858                                         return pol;
 859                                 }
 860                                 __xfrm_policy_unlink(pol, dir);
 861                         }
 862                         ret = pol;
 863                         break;
 864                 }
 865         }
 866         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 867
 868         if (ret && delete)
 869                 xfrm_policy_kill(ret);
 870         return ret;
 871 }
 872 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 873
 874 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
 875                                      int dir, u32 id, int delete, int *err)
 876 {
 877         struct xfrm_policy *pol, *ret;
 878         struct hlist_head *chain;
 879
 880         *err = -ENOENT;
 881         if (xfrm_policy_id2dir(id) != dir)
 882                 return NULL;
 883
 884         *err = 0;
 885         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 886         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 887         ret = NULL;
 888         hlist_for_each_entry(pol, chain, byidx) {
 889                 if (pol->type == type && pol->index == id &&
 890                     (mark & pol->mark.m) == pol->mark.v) {
 891                         xfrm_pol_hold(pol);
 892                         if (delete) {
 893                                 *err = security_xfrm_policy_delete(
 894                                                                 pol->security);
 895                                 if (*err) {
 896                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 897                                         return pol;
 898                                 }
 899                                 __xfrm_policy_unlink(pol, dir);
 900                         }
 901                         ret = pol;
 902                         break;
 903                 }
 904         }
 905         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 906
 907         if (ret && delete)
 908                 xfrm_policy_kill(ret);
 909         return ret;
 910 }
 911 EXPORT_SYMBOL(xfrm_policy_byid);
 912
 913 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 914 static inline int
 915 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 916 {
 917         int dir, err = 0;
 918
 919         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 920                 struct xfrm_policy *pol;
 921                 int i;
 922
 923                 hlist_for_each_entry(pol,
 924                                      &net->xfrm.policy_inexact[dir], bydst) {
 925                         if (pol->type != type)
 926                                 continue;
 927                         err = security_xfrm_policy_delete(pol->security);
 928                         if (err) {
 929                                 xfrm_audit_policy_delete(pol, 0, task_valid);
 930                                 return err;
 931                         }
 932                 }
 933                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 934                         hlist_for_each_entry(pol,
 935                                              net->xfrm.policy_bydst[dir].table + i,
 936                                              bydst) {
 937                                 if (pol->type != type)
 938                                         continue;
 939                                 err = security_xfrm_policy_delete(
 940                                                                 pol->security);
 941                                 if (err) {
 942                                         xfrm_audit_policy_delete(pol, 0,
 943                                                                  task_valid);
 944                                         return err;
 945                                 }
 946                         }
 947                 }
 948         }
 949         return err;
 950 }
 951 #else
 952 static inline int
 953 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 954 {
 955         return 0;
 956 }
 957 #endif
 958
 959 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
 960 {
 961         int dir, err = 0, cnt = 0;
 962
 963         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 964
 965         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
 966         if (err)
 967                 goto out;
 968
 969         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 970                 struct xfrm_policy *pol;
 971                 int i;
 972
 973         again1:
 974                 hlist_for_each_entry(pol,
 975                                      &net->xfrm.policy_inexact[dir], bydst) {
 976                         if (pol->type != type)
 977                                 continue;
 978                         __xfrm_policy_unlink(pol, dir);
 979                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 980                         cnt++;
 981
 982                         xfrm_audit_policy_delete(pol, 1, task_valid);
 983
 984                         xfrm_policy_kill(pol);
 985
 986                         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 987                         goto again1;
 988                 }
 989
 990                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 991         again2:
 992                         hlist_for_each_entry(pol,
 993                                              net->xfrm.policy_bydst[dir].table + i,
 994                                              bydst) {
 995                                 if (pol->type != type)
 996                                         continue;
 997                                 __xfrm_policy_unlink(pol, dir);
 998                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 999                                 cnt++;
1000
1001                                 xfrm_audit_policy_delete(pol, 1, task_valid);
1002                                 xfrm_policy_kill(pol);
1003
1004                                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1005                                 goto again2;
1006                         }
1007                 }
1008
1009         }
1010         if (!cnt)
1011                 err = -ESRCH;
1012 out:
1013         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1014         return err;
1015 }
1016 EXPORT_SYMBOL(xfrm_policy_flush);
1017
1018 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1019                      int (*func)(struct xfrm_policy *, int, int, void*),
1020                      void *data)
1021 {
1022         struct xfrm_policy *pol;
1023         struct xfrm_policy_walk_entry *x;
1024         int error = 0;
1025
1026         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1027             walk->type != XFRM_POLICY_TYPE_ANY)
1028                 return -EINVAL;
1029
1030         if (list_empty(&walk->walk.all) && walk->seq != 0)
1031                 return 0;
1032
1033         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1034         if (list_empty(&walk->walk.all))
1035                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1036         else
1037                 x = list_first_entry(&walk->walk.all,
1038                                      struct xfrm_policy_walk_entry, all);
1039
1040         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1041                 if (x->dead)
1042                         continue;
1043                 pol = container_of(x, struct xfrm_policy, walk);
1044                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1045                     walk->type != pol->type)
1046                         continue;
1047                 error = func(pol, xfrm_policy_id2dir(pol->index),
1048                              walk->seq, data);
1049                 if (error) {
1050                         list_move_tail(&walk->walk.all, &x->all);
1051                         goto out;
1052                 }
1053                 walk->seq++;
1054         }
1055         if (walk->seq == 0) {
1056                 error = -ENOENT;
1057                 goto out;
1058         }
1059         list_del_init(&walk->walk.all);
1060 out:
1061         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1062         return error;
1063 }
1064 EXPORT_SYMBOL(xfrm_policy_walk);
1065
1066 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1067 {
1068         INIT_LIST_HEAD(&walk->walk.all);
1069         walk->walk.dead = 1;
1070         walk->type = type;
1071         walk->seq = 0;
1072 }
1073 EXPORT_SYMBOL(xfrm_policy_walk_init);
1074
1075 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1076 {
1077         if (list_empty(&walk->walk.all))
1078                 return;
1079
1080         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1081         list_del(&walk->walk.all);
1082         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1083 }
1084 EXPORT_SYMBOL(xfrm_policy_walk_done);
1085
1086 /*
1087  * Find policy to apply to this flow.
1088  *
1089  * Returns 0 if policy found, else an -errno.
1090  */
1091 static int xfrm_policy_match(const struct xfrm_policy *pol,
1092                              const struct flowi *fl,
1093                              u8 type, u16 family, int dir)
1094 {
1095         const struct xfrm_selector *sel = &pol->selector;
1096         int ret = -ESRCH;
1097         bool match;
1098
1099         if (pol->family != family ||
1100             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1101             pol->type != type)
1102                 return ret;
1103
1104         match = xfrm_selector_match(sel, fl, family);
1105         if (match)
1106                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1107                                                   dir);
1108
1109         return ret;
1110 }
1111
1112 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1113                                                      const struct flowi *fl,
1114                                                      u16 family, u8 dir)
1115 {
1116         int err;
1117         struct xfrm_policy *pol, *ret;
1118         const xfrm_address_t *daddr, *saddr;
1119         struct hlist_head *chain;
1120         unsigned int sequence;
1121         u32 priority;
1122
1123         daddr = xfrm_flowi_daddr(fl, family);
1124         saddr = xfrm_flowi_saddr(fl, family);
1125         if (unlikely(!daddr || !saddr))
1126                 return NULL;
1127
1128         rcu_read_lock();
1129  retry:
1130         do {
1131                 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1132                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1133         } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1134
1135         priority = ~0U;
1136         ret = NULL;
1137         hlist_for_each_entry_rcu(pol, chain, bydst) {
1138                 err = xfrm_policy_match(pol, fl, type, family, dir);
1139                 if (err) {
1140                         if (err == -ESRCH)
1141                                 continue;
1142                         else {
1143                                 ret = ERR_PTR(err);
1144                                 goto fail;
1145                         }
1146                 } else {
1147                         ret = pol;
1148                         priority = ret->priority;
1149                         break;
1150                 }
1151         }
1152         chain = &net->xfrm.policy_inexact[dir];
1153         hlist_for_each_entry_rcu(pol, chain, bydst) {
1154                 if ((pol->priority >= priority) && ret)
1155                         break;
1156
1157                 err = xfrm_policy_match(pol, fl, type, family, dir);
1158                 if (err) {
1159                         if (err == -ESRCH)
1160                                 continue;
1161                         else {
1162                                 ret = ERR_PTR(err);
1163                                 goto fail;
1164                         }
1165                 } else {
1166                         ret = pol;
1167                         break;
1168                 }
1169         }
1170
1171         if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1172                 goto retry;
1173
1174         if (ret && !xfrm_pol_hold_rcu(ret))
1175                 goto retry;
1176 fail:
1177         rcu_read_unlock();
1178
1179         return ret;
1180 }
1181
1182 static struct xfrm_policy *
1183 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1184 {
1185 #ifdef CONFIG_XFRM_SUB_POLICY
1186         struct xfrm_policy *pol;
1187
1188         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1189         if (pol != NULL)
1190                 return pol;
1191 #endif
1192         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1193 }
1194
1195 static int flow_to_policy_dir(int dir)
1196 {
1197         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1198             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1199             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1200                 return dir;
1201
1202         switch (dir) {
1203         default:
1204         case FLOW_DIR_IN:
1205                 return XFRM_POLICY_IN;
1206         case FLOW_DIR_OUT:
1207                 return XFRM_POLICY_OUT;
1208         case FLOW_DIR_FWD:
1209                 return XFRM_POLICY_FWD;
1210         }
1211 }
1212
1213 static struct flow_cache_object *
1214 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1215                    u8 dir, struct flow_cache_object *old_obj, void *ctx)
1216 {
1217         struct xfrm_policy *pol;
1218
1219         if (old_obj)
1220                 xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1221
1222         pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
1223         if (IS_ERR_OR_NULL(pol))
1224                 return ERR_CAST(pol);
1225
1226         /* Resolver returns two references:
1227          * one for cache and one for caller of flow_cache_lookup() */
1228         xfrm_pol_hold(pol);
1229
1230         return &pol->flo;
1231 }
1232
1233 static inline int policy_to_flow_dir(int dir)
1234 {
1235         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1236             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1237             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1238                 return dir;
1239         switch (dir) {
1240         default:
1241         case XFRM_POLICY_IN:
1242                 return FLOW_DIR_IN;
1243         case XFRM_POLICY_OUT:
1244                 return FLOW_DIR_OUT;
1245         case XFRM_POLICY_FWD:
1246                 return FLOW_DIR_FWD;
1247         }
1248 }
1249
1250 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1251                                                  const struct flowi *fl)
1252 {
1253         struct xfrm_policy *pol;
1254
1255         rcu_read_lock();
1256  again:
1257         pol = rcu_dereference(sk->sk_policy[dir]);
1258         if (pol != NULL) {
1259                 bool match = xfrm_selector_match(&pol->selector, fl,
1260                                                  sk->sk_family);
1261                 int err = 0;
1262
1263                 if (match) {
1264                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1265                                 pol = NULL;
1266                                 goto out;
1267                         }
1268                         err = security_xfrm_policy_lookup(pol->security,
1269                                                       fl->flowi_secid,
1270                                                       policy_to_flow_dir(dir));
1271                         if (!err && !xfrm_pol_hold_rcu(pol))
1272                                 goto again;
1273                         else if (err == -ESRCH)
1274                                 pol = NULL;
1275                         else
1276                                 pol = ERR_PTR(err);
1277                 } else
1278                         pol = NULL;
1279         }
1280 out:
1281         rcu_read_unlock();
1282         return pol;
1283 }
1284
1285 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1286 {
1287         struct net *net = xp_net(pol);
1288
1289         list_add(&pol->walk.all, &net->xfrm.policy_all);
1290         net->xfrm.policy_count[dir]++;
1291         xfrm_pol_hold(pol);
1292 }
1293
1294 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1295                                                 int dir)
1296 {
1297         struct net *net = xp_net(pol);
1298
1299         if (list_empty(&pol->walk.all))
1300                 return NULL;
1301
1302         /* Socket policies are not hashed. */
1303         if (!hlist_unhashed(&pol->bydst)) {
1304                 hlist_del_rcu(&pol->bydst);
1305                 hlist_del(&pol->byidx);
1306         }
1307
1308         list_del_init(&pol->walk.all);
1309         net->xfrm.policy_count[dir]--;
1310
1311         return pol;
1312 }
1313
1314 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1315 {
1316         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1317 }
1318
1319 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1320 {
1321         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1322 }
1323
1324 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1325 {
1326         struct net *net = xp_net(pol);
1327
1328         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1329         pol = __xfrm_policy_unlink(pol, dir);
1330         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1331         if (pol) {
1332                 xfrm_policy_kill(pol);
1333                 return 0;
1334         }
1335         return -ENOENT;
1336 }
1337 EXPORT_SYMBOL(xfrm_policy_delete);
1338
1339 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1340 {
1341         struct net *net = xp_net(pol);
1342         struct xfrm_policy *old_pol;
1343
1344 #ifdef CONFIG_XFRM_SUB_POLICY
1345         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1346                 return -EINVAL;
1347 #endif
1348
1349         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1350         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1351                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1352         if (pol) {
1353                 pol->curlft.add_time = get_seconds();
1354                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1355                 xfrm_sk_policy_link(pol, dir);
1356         }
1357         rcu_assign_pointer(sk->sk_policy[dir], pol);
1358         if (old_pol) {
1359                 if (pol)
1360                         xfrm_policy_requeue(old_pol, pol);
1361
1362                 /* Unlinking succeeds always. This is the only function
1363                  * allowed to delete or replace socket policy.
1364                  */
1365                 xfrm_sk_policy_unlink(old_pol, dir);
1366         }
1367         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1368
1369         if (old_pol) {
1370                 xfrm_policy_kill(old_pol);
1371         }
1372         return 0;
1373 }
1374
1375 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1376 {
1377         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1378         struct net *net = xp_net(old);
1379
1380         if (newp) {
1381                 newp->selector = old->selector;
1382                 if (security_xfrm_policy_clone(old->security,
1383                                                &newp->security)) {
1384                         kfree(newp);
1385                         return NULL;  /* ENOMEM */
1386                 }
1387                 newp->lft = old->lft;
1388                 newp->curlft = old->curlft;
1389                 newp->mark = old->mark;
1390                 newp->action = old->action;
1391                 newp->flags = old->flags;
1392                 newp->xfrm_nr = old->xfrm_nr;
1393                 newp->index = old->index;
1394                 newp->type = old->type;
1395                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1396                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1397                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1398                 xfrm_sk_policy_link(newp, dir);
1399                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1400                 xfrm_pol_put(newp);
1401         }
1402         return newp;
1403 }
1404
1405 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1406 {
1407         const struct xfrm_policy *p;
1408         struct xfrm_policy *np;
1409         int i, ret = 0;
1410
1411         rcu_read_lock();
1412         for (i = 0; i < 2; i++) {
1413                 p = rcu_dereference(osk->sk_policy[i]);
1414                 if (p) {
1415                         np = clone_policy(p, i);
1416                         if (unlikely(!np)) {
1417                                 ret = -ENOMEM;
1418                                 break;
1419                         }
1420                         rcu_assign_pointer(sk->sk_policy[i], np);
1421                 }
1422         }
1423         rcu_read_unlock();
1424         return ret;
1425 }
1426
1427 static int
1428 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1429                xfrm_address_t *remote, unsigned short family)
1430 {
1431         int err;
1432         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1433
1434         if (unlikely(afinfo == NULL))
1435                 return -EINVAL;
1436         err = afinfo->get_saddr(net, oif, local, remote);
1437         xfrm_policy_put_afinfo(afinfo);
1438         return err;
1439 }
1440
1441 /* Resolve list of templates for the flow, given policy. */
1442
1443 static int
1444 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1445                       struct xfrm_state **xfrm, unsigned short family)
1446 {
1447         struct net *net = xp_net(policy);
1448         int nx;
1449         int i, error;
1450         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1451         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1452         xfrm_address_t tmp;
1453
1454         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1455                 struct xfrm_state *x;
1456                 xfrm_address_t *remote = daddr;
1457                 xfrm_address_t *local  = saddr;
1458                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1459
1460                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1461                     tmpl->mode == XFRM_MODE_BEET) {
1462                         remote = &tmpl->id.daddr;
1463                         local = &tmpl->saddr;
1464                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1465                                 error = xfrm_get_saddr(net, fl->flowi_oif,
1466                                                        &tmp, remote,
1467                                                        tmpl->encap_family);
1468                                 if (error)
1469                                         goto fail;
1470                                 local = &tmp;
1471                         }
1472                 }
1473
1474                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1475
1476                 if (x && x->km.state == XFRM_STATE_VALID) {
1477                         xfrm[nx++] = x;
1478                         daddr = remote;
1479                         saddr = local;
1480                         continue;
1481                 }
1482                 if (x) {
1483                         error = (x->km.state == XFRM_STATE_ERROR ?
1484                                  -EINVAL : -EAGAIN);
1485                         xfrm_state_put(x);
1486                 } else if (error == -ESRCH) {
1487                         error = -EAGAIN;
1488                 }
1489
1490                 if (!tmpl->optional)
1491                         goto fail;
1492         }
1493         return nx;
1494
1495 fail:
1496         for (nx--; nx >= 0; nx--)
1497                 xfrm_state_put(xfrm[nx]);
1498         return error;
1499 }
1500
1501 static int
1502 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1503                   struct xfrm_state **xfrm, unsigned short family)
1504 {
1505         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1506         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1507         int cnx = 0;
1508         int error;
1509         int ret;
1510         int i;
1511
1512         for (i = 0; i < npols; i++) {
1513                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1514                         error = -ENOBUFS;
1515                         goto fail;
1516                 }
1517
1518                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1519                 if (ret < 0) {
1520                         error = ret;
1521                         goto fail;
1522                 } else
1523                         cnx += ret;
1524         }
1525
1526         /* found states are sorted for outbound processing */
1527         if (npols > 1)
1528                 xfrm_state_sort(xfrm, tpp, cnx, family);
1529
1530         return cnx;
1531
1532  fail:
1533         for (cnx--; cnx >= 0; cnx--)
1534                 xfrm_state_put(tpp[cnx]);
1535         return error;
1536
1537 }
1538
1539 /* Check that the bundle accepts the flow and its components are
1540  * still valid.
1541  */
1542
1543 static inline int xfrm_get_tos(const struct flowi *fl, int family)
1544 {
1545         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1546         int tos;
1547
1548         if (!afinfo)
1549                 return -EINVAL;
1550
1551         tos = afinfo->get_tos(fl);
1552
1553         xfrm_policy_put_afinfo(afinfo);
1554
1555         return tos;
1556 }
1557
1558 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1559 {
1560         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1561         struct dst_entry *dst = &xdst->u.dst;
1562
1563         if (xdst->route == NULL) {
1564                 /* Dummy bundle - if it has xfrms we were not
1565                  * able to build bundle as template resolution failed.
1566                  * It means we need to try again resolving. */
1567                 if (xdst->num_xfrms > 0)
1568                         return NULL;
1569         } else if (dst->flags & DST_XFRM_QUEUE) {
1570                 return NULL;
1571         } else {
1572                 /* Real bundle */
1573                 if (stale_bundle(dst))
1574                         return NULL;
1575         }
1576
1577         dst_hold(dst);
1578         return flo;
1579 }
1580
1581 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1582 {
1583         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1584         struct dst_entry *dst = &xdst->u.dst;
1585
1586         if (!xdst->route)
1587                 return 0;
1588         if (stale_bundle(dst))
1589                 return 0;
1590
1591         return 1;
1592 }
1593
1594 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1595 {
1596         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1597         struct dst_entry *dst = &xdst->u.dst;
1598
1599         dst_free(dst);
1600 }
1601
1602 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1603         .get = xfrm_bundle_flo_get,
1604         .check = xfrm_bundle_flo_check,
1605         .delete = xfrm_bundle_flo_delete,
1606 };
1607
1608 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1609 {
1610         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1611         struct dst_ops *dst_ops;
1612         struct xfrm_dst *xdst;
1613
1614         if (!afinfo)
1615                 return ERR_PTR(-EINVAL);
1616
1617         switch (family) {
1618         case AF_INET:
1619                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1620                 break;
1621 #if IS_ENABLED(CONFIG_IPV6)
1622         case AF_INET6:
1623                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1624                 break;
1625 #endif
1626         default:
1627                 BUG();
1628         }
1629         xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1630
1631         if (likely(xdst)) {
1632                 struct dst_entry *dst = &xdst->u.dst;
1633
1634                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1635                 xdst->flo.ops = &xfrm_bundle_fc_ops;
1636         } else
1637                 xdst = ERR_PTR(-ENOBUFS);
1638
1639         xfrm_policy_put_afinfo(afinfo);
1640
1641         return xdst;
1642 }
1643
1644 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1645                                  int nfheader_len)
1646 {
1647         struct xfrm_policy_afinfo *afinfo =
1648                 xfrm_policy_get_afinfo(dst->ops->family);
1649         int err;
1650
1651         if (!afinfo)
1652                 return -EINVAL;
1653
1654         err = afinfo->init_path(path, dst, nfheader_len);
1655
1656         xfrm_policy_put_afinfo(afinfo);
1657
1658         return err;
1659 }
1660
1661 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1662                                 const struct flowi *fl)
1663 {
1664         struct xfrm_policy_afinfo *afinfo =
1665                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1666         int err;
1667
1668         if (!afinfo)
1669                 return -EINVAL;
1670
1671         err = afinfo->fill_dst(xdst, dev, fl);
1672
1673         xfrm_policy_put_afinfo(afinfo);
1674
1675         return err;
1676 }
1677
1678
1679 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1680  * all the metrics... Shortly, bundle a bundle.
1681  */
1682
1683 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1684                                             struct xfrm_state **xfrm, int nx,
1685                                             const struct flowi *fl,
1686                                             struct dst_entry *dst)
1687 {
1688         struct net *net = xp_net(policy);
1689         unsigned long now = jiffies;
1690         struct net_device *dev;
1691         struct xfrm_mode *inner_mode;
1692         struct dst_entry *dst_prev = NULL;
1693         struct dst_entry *dst0 = NULL;
1694         int i = 0;
1695         int err;
1696         int header_len = 0;
1697         int nfheader_len = 0;
1698         int trailer_len = 0;
1699         int tos;
1700         int family = policy->selector.family;
1701         xfrm_address_t saddr, daddr;
1702
1703         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1704
1705         tos = xfrm_get_tos(fl, family);
1706         err = tos;
1707         if (tos < 0)
1708                 goto put_states;
1709
1710         dst_hold(dst);
1711
1712         for (; i < nx; i++) {
1713                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1714                 struct dst_entry *dst1 = &xdst->u.dst;
1715
1716                 err = PTR_ERR(xdst);
1717                 if (IS_ERR(xdst)) {
1718                         dst_release(dst);
1719                         goto put_states;
1720                 }
1721
1722                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1723                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1724                                                         xfrm_af2proto(family));
1725                         if (!inner_mode) {
1726                                 err = -EAFNOSUPPORT;
1727                                 dst_release(dst);
1728                                 goto put_states;
1729                         }
1730                 } else
1731                         inner_mode = xfrm[i]->inner_mode;
1732
1733                 if (!dst_prev)
1734                         dst0 = dst1;
1735                 else {
1736                         dst_prev->child = dst_clone(dst1);
1737                         dst1->flags |= DST_NOHASH;
1738                 }
1739
1740                 xdst->route = dst;
1741                 dst_copy_metrics(dst1, dst);
1742
1743                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1744                         family = xfrm[i]->props.family;
1745                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1746                                               &saddr, &daddr, family);
1747                         err = PTR_ERR(dst);
1748                         if (IS_ERR(dst))
1749                                 goto put_states;
1750                 } else
1751                         dst_hold(dst);
1752
1753                 dst1->xfrm = xfrm[i];
1754                 xdst->xfrm_genid = xfrm[i]->genid;
1755
1756                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1757                 dst1->flags |= DST_HOST;
1758                 dst1->lastuse = now;
1759
1760                 dst1->input = dst_discard;
1761                 dst1->output = inner_mode->afinfo->output;
1762
1763                 dst1->next = dst_prev;
1764                 dst_prev = dst1;
1765
1766                 header_len += xfrm[i]->props.header_len;
1767                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1768                         nfheader_len += xfrm[i]->props.header_len;
1769                 trailer_len += xfrm[i]->props.trailer_len;
1770         }
1771
1772         dst_prev->child = dst;
1773         dst0->path = dst;
1774
1775         err = -ENODEV;
1776         dev = dst->dev;
1777         if (!dev)
1778                 goto free_dst;
1779
1780         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1781         xfrm_init_pmtu(dst_prev);
1782
1783         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1784                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1785
1786                 err = xfrm_fill_dst(xdst, dev, fl);
1787                 if (err)
1788                         goto free_dst;
1789
1790                 dst_prev->header_len = header_len;
1791                 dst_prev->trailer_len = trailer_len;
1792                 header_len -= xdst->u.dst.xfrm->props.header_len;
1793                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1794         }
1795
1796 out:
1797         return dst0;
1798
1799 put_states:
1800         for (; i < nx; i++)
1801                 xfrm_state_put(xfrm[i]);
1802 free_dst:
1803         if (dst0)
1804                 dst_free(dst0);
1805         dst0 = ERR_PTR(err);
1806         goto out;
1807 }
1808
1809 #ifdef CONFIG_XFRM_SUB_POLICY
1810 static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
1811 {
1812         if (!*target) {
1813                 *target = kmalloc(size, GFP_ATOMIC);
1814                 if (!*target)
1815                         return -ENOMEM;
1816         }
1817
1818         memcpy(*target, src, size);
1819         return 0;
1820 }
1821 #endif
1822
1823 static int xfrm_dst_update_parent(struct dst_entry *dst,
1824                                   const struct xfrm_selector *sel)
1825 {
1826 #ifdef CONFIG_XFRM_SUB_POLICY
1827         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1828         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1829                                    sel, sizeof(*sel));
1830 #else
1831         return 0;
1832 #endif
1833 }
1834
1835 static int xfrm_dst_update_origin(struct dst_entry *dst,
1836                                   const struct flowi *fl)
1837 {
1838 #ifdef CONFIG_XFRM_SUB_POLICY
1839         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1840         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1841 #else
1842         return 0;
1843 #endif
1844 }
1845
1846 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1847                                 struct xfrm_policy **pols,
1848                                 int *num_pols, int *num_xfrms)
1849 {
1850         int i;
1851
1852         if (*num_pols == 0 || !pols[0]) {
1853                 *num_pols = 0;
1854                 *num_xfrms = 0;
1855                 return 0;
1856         }
1857         if (IS_ERR(pols[0]))
1858                 return PTR_ERR(pols[0]);
1859
1860         *num_xfrms = pols[0]->xfrm_nr;
1861
1862 #ifdef CONFIG_XFRM_SUB_POLICY
1863         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1864             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1865                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1866                                                     XFRM_POLICY_TYPE_MAIN,
1867                                                     fl, family,
1868                                                     XFRM_POLICY_OUT);
1869                 if (pols[1]) {
1870                         if (IS_ERR(pols[1])) {
1871                                 xfrm_pols_put(pols, *num_pols);
1872                                 return PTR_ERR(pols[1]);
1873                         }
1874                         (*num_pols)++;
1875                         (*num_xfrms) += pols[1]->xfrm_nr;
1876                 }
1877         }
1878 #endif
1879         for (i = 0; i < *num_pols; i++) {
1880                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1881                         *num_xfrms = -1;
1882                         break;
1883                 }
1884         }
1885
1886         return 0;
1887
1888 }
1889
1890 static struct xfrm_dst *
1891 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1892                                const struct flowi *fl, u16 family,
1893                                struct dst_entry *dst_orig)
1894 {
1895         struct net *net = xp_net(pols[0]);
1896         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1897         struct dst_entry *dst;
1898         struct xfrm_dst *xdst;
1899         int err;
1900
1901         /* Try to instantiate a bundle */
1902         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1903         if (err <= 0) {
1904                 if (err != 0 && err != -EAGAIN)
1905                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1906                 return ERR_PTR(err);
1907         }
1908
1909         dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1910         if (IS_ERR(dst)) {
1911                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1912                 return ERR_CAST(dst);
1913         }
1914
1915         xdst = (struct xfrm_dst *)dst;
1916         xdst->num_xfrms = err;
1917         if (num_pols > 1)
1918                 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1919         else
1920                 err = xfrm_dst_update_origin(dst, fl);
1921         if (unlikely(err)) {
1922                 dst_free(dst);
1923                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1924                 return ERR_PTR(err);
1925         }
1926
1927         xdst->num_pols = num_pols;
1928         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1929         xdst->policy_genid = atomic_read(&pols[0]->genid);
1930
1931         return xdst;
1932 }
1933
1934 static void xfrm_policy_queue_process(unsigned long arg)
1935 {
1936         struct sk_buff *skb;
1937         struct sock *sk;
1938         struct dst_entry *dst;
1939         struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1940         struct net *net = xp_net(pol);
1941         struct xfrm_policy_queue *pq = &pol->polq;
1942         struct flowi fl;
1943         struct sk_buff_head list;
1944
1945         spin_lock(&pq->hold_queue.lock);
1946         skb = skb_peek(&pq->hold_queue);
1947         if (!skb) {
1948                 spin_unlock(&pq->hold_queue.lock);
1949                 goto out;
1950         }
1951         dst = skb_dst(skb);
1952         sk = skb->sk;
1953         xfrm_decode_session(skb, &fl, dst->ops->family);
1954         spin_unlock(&pq->hold_queue.lock);
1955
1956         dst_hold(dst->path);
1957         dst = xfrm_lookup(net, dst->path, &fl, sk, 0);
1958         if (IS_ERR(dst))
1959                 goto purge_queue;
1960
1961         if (dst->flags & DST_XFRM_QUEUE) {
1962                 dst_release(dst);
1963
1964                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1965                         goto purge_queue;
1966
1967                 pq->timeout = pq->timeout << 1;
1968                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1969                         xfrm_pol_hold(pol);
1970         goto out;
1971         }
1972
1973         dst_release(dst);
1974
1975         __skb_queue_head_init(&list);
1976
1977         spin_lock(&pq->hold_queue.lock);
1978         pq->timeout = 0;
1979         skb_queue_splice_init(&pq->hold_queue, &list);
1980         spin_unlock(&pq->hold_queue.lock);
1981
1982         while (!skb_queue_empty(&list)) {
1983                 skb = __skb_dequeue(&list);
1984
1985                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1986                 dst_hold(skb_dst(skb)->path);
1987                 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0);
1988                 if (IS_ERR(dst)) {
1989                         kfree_skb(skb);
1990                         continue;
1991                 }
1992
1993                 nf_reset(skb);
1994                 skb_dst_drop(skb);
1995                 skb_dst_set(skb, dst);
1996
1997                 dst_output(net, skb->sk, skb);
1998         }
1999
2000 out:
2001         xfrm_pol_put(pol);
2002         return;
2003
2004 purge_queue:
2005         pq->timeout = 0;
2006         skb_queue_purge(&pq->hold_queue);
2007         xfrm_pol_put(pol);
2008 }
2009
2010 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2011 {
2012         unsigned long sched_next;
2013         struct dst_entry *dst = skb_dst(skb);
2014         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2015         struct xfrm_policy *pol = xdst->pols[0];
2016         struct xfrm_policy_queue *pq = &pol->polq;
2017
2018         if (unlikely(skb_fclone_busy(sk, skb))) {
2019                 kfree_skb(skb);
2020                 return 0;
2021         }
2022
2023         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2024                 kfree_skb(skb);
2025                 return -EAGAIN;
2026         }
2027
2028         skb_dst_force(skb);
2029
2030         spin_lock_bh(&pq->hold_queue.lock);
2031
2032         if (!pq->timeout)
2033                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2034
2035         sched_next = jiffies + pq->timeout;
2036
2037         if (del_timer(&pq->hold_timer)) {
2038                 if (time_before(pq->hold_timer.expires, sched_next))
2039                         sched_next = pq->hold_timer.expires;
2040                 xfrm_pol_put(pol);
2041         }
2042
2043         __skb_queue_tail(&pq->hold_queue, skb);
2044         if (!mod_timer(&pq->hold_timer, sched_next))
2045                 xfrm_pol_hold(pol);
2046
2047         spin_unlock_bh(&pq->hold_queue.lock);
2048
2049         return 0;
2050 }
2051
2052 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2053                                                  struct xfrm_flo *xflo,
2054                                                  const struct flowi *fl,
2055                                                  int num_xfrms,
2056                                                  u16 family)
2057 {
2058         int err;
2059         struct net_device *dev;
2060         struct dst_entry *dst;
2061         struct dst_entry *dst1;
2062         struct xfrm_dst *xdst;
2063
2064         xdst = xfrm_alloc_dst(net, family);
2065         if (IS_ERR(xdst))
2066                 return xdst;
2067
2068         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2069             net->xfrm.sysctl_larval_drop ||
2070             num_xfrms <= 0)
2071                 return xdst;
2072
2073         dst = xflo->dst_orig;
2074         dst1 = &xdst->u.dst;
2075         dst_hold(dst);
2076         xdst->route = dst;
2077
2078         dst_copy_metrics(dst1, dst);
2079
2080         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2081         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2082         dst1->lastuse = jiffies;
2083
2084         dst1->input = dst_discard;
2085         dst1->output = xdst_queue_output;
2086
2087         dst_hold(dst);
2088         dst1->child = dst;
2089         dst1->path = dst;
2090
2091         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2092
2093         err = -ENODEV;
2094         dev = dst->dev;
2095         if (!dev)
2096                 goto free_dst;
2097
2098         err = xfrm_fill_dst(xdst, dev, fl);
2099         if (err)
2100                 goto free_dst;
2101
2102 out:
2103         return xdst;
2104
2105 free_dst:
2106         dst_release(dst1);
2107         xdst = ERR_PTR(err);
2108         goto out;
2109 }
2110
2111 static struct flow_cache_object *
2112 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
2113                    struct flow_cache_object *oldflo, void *ctx)
2114 {
2115         struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
2116         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2117         struct xfrm_dst *xdst, *new_xdst;
2118         int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
2119
2120         /* Check if the policies from old bundle are usable */
2121         xdst = NULL;
2122         if (oldflo) {
2123                 xdst = container_of(oldflo, struct xfrm_dst, flo);
2124                 num_pols = xdst->num_pols;
2125                 num_xfrms = xdst->num_xfrms;
2126                 pol_dead = 0;
2127                 for (i = 0; i < num_pols; i++) {
2128                         pols[i] = xdst->pols[i];
2129                         pol_dead |= pols[i]->walk.dead;
2130                 }
2131                 if (pol_dead) {
2132                         dst_free(&xdst->u.dst);
2133                         xdst = NULL;
2134                         num_pols = 0;
2135                         num_xfrms = 0;
2136                         oldflo = NULL;
2137                 }
2138         }
2139
2140         /* Resolve policies to use if we couldn't get them from
2141          * previous cache entry */
2142         if (xdst == NULL) {
2143                 num_pols = 1;
2144                 pols[0] = __xfrm_policy_lookup(net, fl, family,
2145                                                flow_to_policy_dir(dir));
2146                 err = xfrm_expand_policies(fl, family, pols,
2147                                            &num_pols, &num_xfrms);
2148                 if (err < 0)
2149                         goto inc_error;
2150                 if (num_pols == 0)
2151                         return NULL;
2152                 if (num_xfrms <= 0)
2153                         goto make_dummy_bundle;
2154         }
2155
2156         new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2157                                                   xflo->dst_orig);
2158         if (IS_ERR(new_xdst)) {
2159                 err = PTR_ERR(new_xdst);
2160                 if (err != -EAGAIN)
2161                         goto error;
2162                 if (oldflo == NULL)
2163                         goto make_dummy_bundle;
2164                 dst_hold(&xdst->u.dst);
2165                 return oldflo;
2166         } else if (new_xdst == NULL) {
2167                 num_xfrms = 0;
2168                 if (oldflo == NULL)
2169                         goto make_dummy_bundle;
2170                 xdst->num_xfrms = 0;
2171                 dst_hold(&xdst->u.dst);
2172                 return oldflo;
2173         }
2174
2175         /* Kill the previous bundle */
2176         if (xdst) {
2177                 /* The policies were stolen for newly generated bundle */
2178                 xdst->num_pols = 0;
2179                 dst_free(&xdst->u.dst);
2180         }
2181
2182         /* Flow cache does not have reference, it dst_free()'s,
2183          * but we do need to return one reference for original caller */
2184         dst_hold(&new_xdst->u.dst);
2185         return &new_xdst->flo;
2186
2187 make_dummy_bundle:
2188         /* We found policies, but there's no bundles to instantiate:
2189          * either because the policy blocks, has no transformations or
2190          * we could not build template (no xfrm_states).*/
2191         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2192         if (IS_ERR(xdst)) {
2193                 xfrm_pols_put(pols, num_pols);
2194                 return ERR_CAST(xdst);
2195         }
2196         xdst->num_pols = num_pols;
2197         xdst->num_xfrms = num_xfrms;
2198         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2199
2200         dst_hold(&xdst->u.dst);
2201         return &xdst->flo;
2202
2203 inc_error:
2204         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2205 error:
2206         if (xdst != NULL)
2207                 dst_free(&xdst->u.dst);
2208         else
2209                 xfrm_pols_put(pols, num_pols);
2210         return ERR_PTR(err);
2211 }
2212
2213 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2214                                         struct dst_entry *dst_orig)
2215 {
2216         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2217         struct dst_entry *ret;
2218
2219         if (!afinfo) {
2220                 dst_release(dst_orig);
2221                 return ERR_PTR(-EINVAL);
2222         } else {
2223                 ret = afinfo->blackhole_route(net, dst_orig);
2224         }
2225         xfrm_policy_put_afinfo(afinfo);
2226
2227         return ret;
2228 }
2229
2230 /* Main function: finds/creates a bundle for given flow.
2231  *
2232  * At the moment we eat a raw IP route. Mostly to speed up lookups
2233  * on interfaces with disabled IPsec.
2234  */
2235 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2236                               const struct flowi *fl,
2237                               const struct sock *sk, int flags)
2238 {
2239         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2240         struct flow_cache_object *flo;
2241         struct xfrm_dst *xdst;
2242         struct dst_entry *dst, *route;
2243         u16 family = dst_orig->ops->family;
2244         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2245         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2246
2247         dst = NULL;
2248         xdst = NULL;
2249         route = NULL;
2250
2251         sk = sk_const_to_full_sk(sk);
2252         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2253                 num_pols = 1;
2254                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2255                 err = xfrm_expand_policies(fl, family, pols,
2256                                            &num_pols, &num_xfrms);
2257                 if (err < 0)
2258                         goto dropdst;
2259
2260                 if (num_pols) {
2261                         if (num_xfrms <= 0) {
2262                                 drop_pols = num_pols;
2263                                 goto no_transform;
2264                         }
2265
2266                         xdst = xfrm_resolve_and_create_bundle(
2267                                         pols, num_pols, fl,
2268                                         family, dst_orig);
2269                         if (IS_ERR(xdst)) {
2270                                 xfrm_pols_put(pols, num_pols);
2271                                 err = PTR_ERR(xdst);
2272                                 goto dropdst;
2273                         } else if (xdst == NULL) {
2274                                 num_xfrms = 0;
2275                                 drop_pols = num_pols;
2276                                 goto no_transform;
2277                         }
2278
2279                         dst_hold(&xdst->u.dst);
2280                         xdst->u.dst.flags |= DST_NOCACHE;
2281                         route = xdst->route;
2282                 }
2283         }
2284
2285         if (xdst == NULL) {
2286                 struct xfrm_flo xflo;
2287
2288                 xflo.dst_orig = dst_orig;
2289                 xflo.flags = flags;
2290
2291                 /* To accelerate a bit...  */
2292                 if ((dst_orig->flags & DST_NOXFRM) ||
2293                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2294                         goto nopol;
2295
2296                 flo = flow_cache_lookup(net, fl, family, dir,
2297                                         xfrm_bundle_lookup, &xflo);
2298                 if (flo == NULL)
2299                         goto nopol;
2300                 if (IS_ERR(flo)) {
2301                         err = PTR_ERR(flo);
2302                         goto dropdst;
2303                 }
2304                 xdst = container_of(flo, struct xfrm_dst, flo);
2305
2306                 num_pols = xdst->num_pols;
2307                 num_xfrms = xdst->num_xfrms;
2308                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2309                 route = xdst->route;
2310         }
2311
2312         dst = &xdst->u.dst;
2313         if (route == NULL && num_xfrms > 0) {
2314                 /* The only case when xfrm_bundle_lookup() returns a
2315                  * bundle with null route, is when the template could
2316                  * not be resolved. It means policies are there, but
2317                  * bundle could not be created, since we don't yet
2318                  * have the xfrm_state's. We need to wait for KM to
2319                  * negotiate new SA's or bail out with error.*/
2320                 if (net->xfrm.sysctl_larval_drop) {
2321                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2322                         err = -EREMOTE;
2323                         goto error;
2324                 }
2325
2326                 err = -EAGAIN;
2327
2328                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2329                 goto error;
2330         }
2331
2332 no_transform:
2333         if (num_pols == 0)
2334                 goto nopol;
2335
2336         if ((flags & XFRM_LOOKUP_ICMP) &&
2337             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2338                 err = -ENOENT;
2339                 goto error;
2340         }
2341
2342         for (i = 0; i < num_pols; i++)
2343                 pols[i]->curlft.use_time = get_seconds();
2344
2345         if (num_xfrms < 0) {
2346                 /* Prohibit the flow */
2347                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2348                 err = -EPERM;
2349                 goto error;
2350         } else if (num_xfrms > 0) {
2351                 /* Flow transformed */
2352                 dst_release(dst_orig);
2353         } else {
2354                 /* Flow passes untransformed */
2355                 dst_release(dst);
2356                 dst = dst_orig;
2357         }
2358 ok:
2359         xfrm_pols_put(pols, drop_pols);
2360         if (dst && dst->xfrm &&
2361             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2362                 dst->flags |= DST_XFRM_TUNNEL;
2363         return dst;
2364
2365 nopol:
2366         if (!(flags & XFRM_LOOKUP_ICMP)) {
2367                 dst = dst_orig;
2368                 goto ok;
2369         }
2370         err = -ENOENT;
2371 error:
2372         dst_release(dst);
2373 dropdst:
2374         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2375                 dst_release(dst_orig);
2376         xfrm_pols_put(pols, drop_pols);
2377         return ERR_PTR(err);
2378 }
2379 EXPORT_SYMBOL(xfrm_lookup);
2380
2381 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2382  * Otherwise we may send out blackholed packets.
2383  */
2384 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2385                                     const struct flowi *fl,
2386                                     const struct sock *sk, int flags)
2387 {
2388         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2389                                             flags | XFRM_LOOKUP_QUEUE |
2390                                             XFRM_LOOKUP_KEEP_DST_REF);
2391
2392         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2393                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2394
2395         return dst;
2396 }
2397 EXPORT_SYMBOL(xfrm_lookup_route);
2398
2399 static inline int
2400 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2401 {
2402         struct xfrm_state *x;
2403
2404         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2405                 return 0;
2406         x = skb->sp->xvec[idx];
2407         if (!x->type->reject)
2408                 return 0;
2409         return x->type->reject(x, skb, fl);
2410 }
2411
2412 /* When skb is transformed back to its "native" form, we have to
2413  * check policy restrictions. At the moment we make this in maximally
2414  * stupid way. Shame on me. :-) Of course, connected sockets must
2415  * have policy cached at them.
2416  */
2417
2418 static inline int
2419 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2420               unsigned short family)
2421 {
2422         if (xfrm_state_kern(x))
2423                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2424         return  x->id.proto == tmpl->id.proto &&
2425                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2426                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2427                 x->props.mode == tmpl->mode &&
2428                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2429                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2430                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2431                   xfrm_state_addr_cmp(tmpl, x, family));
2432 }
2433
2434 /*
2435  * 0 or more than 0 is returned when validation is succeeded (either bypass
2436  * because of optional transport mode, or next index of the mathced secpath
2437  * state with the template.
2438  * -1 is returned when no matching template is found.
2439  * Otherwise "-2 - errored_index" is returned.
2440  */
2441 static inline int
2442 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2443                unsigned short family)
2444 {
2445         int idx = start;
2446
2447         if (tmpl->optional) {
2448                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2449                         return start;
2450         } else
2451                 start = -1;
2452         for (; idx < sp->len; idx++) {
2453                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2454                         return ++idx;
2455                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2456                         if (start == -1)
2457                                 start = -2-idx;
2458                         break;
2459                 }
2460         }
2461         return start;
2462 }
2463
2464 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2465                           unsigned int family, int reverse)
2466 {
2467         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2468         int err;
2469
2470         if (unlikely(afinfo == NULL))
2471                 return -EAFNOSUPPORT;
2472
2473         afinfo->decode_session(skb, fl, reverse);
2474         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2475         xfrm_policy_put_afinfo(afinfo);
2476         return err;
2477 }
2478 EXPORT_SYMBOL(__xfrm_decode_session);
2479
2480 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2481 {
2482         for (; k < sp->len; k++) {
2483                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2484                         *idxp = k;
2485                         return 1;
2486                 }
2487         }
2488
2489         return 0;
2490 }
2491
2492 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2493                         unsigned short family)
2494 {
2495         struct net *net = dev_net(skb->dev);
2496         struct xfrm_policy *pol;
2497         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2498         int npols = 0;
2499         int xfrm_nr;
2500         int pi;
2501         int reverse;
2502         struct flowi fl;
2503         u8 fl_dir;
2504         int xerr_idx = -1;
2505
2506         reverse = dir & ~XFRM_POLICY_MASK;
2507         dir &= XFRM_POLICY_MASK;
2508         fl_dir = policy_to_flow_dir(dir);
2509
2510         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2511                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2512                 return 0;
2513         }
2514
2515         nf_nat_decode_session(skb, &fl, family);
2516
2517         /* First, check used SA against their selectors. */
2518         if (skb->sp) {
2519                 int i;
2520
2521                 for (i = skb->sp->len-1; i >= 0; i--) {
2522                         struct xfrm_state *x = skb->sp->xvec[i];
2523                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2524                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2525                                 return 0;
2526                         }
2527                 }
2528         }
2529
2530         pol = NULL;
2531         sk = sk_to_full_sk(sk);
2532         if (sk && sk->sk_policy[dir]) {
2533                 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2534                 if (IS_ERR(pol)) {
2535                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2536                         return 0;
2537                 }
2538         }
2539
2540         if (!pol) {
2541                 struct flow_cache_object *flo;
2542
2543                 flo = flow_cache_lookup(net, &fl, family, fl_dir,
2544                                         xfrm_policy_lookup, NULL);
2545                 if (IS_ERR_OR_NULL(flo))
2546                         pol = ERR_CAST(flo);
2547                 else
2548                         pol = container_of(flo, struct xfrm_policy, flo);
2549         }
2550
2551         if (IS_ERR(pol)) {
2552                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2553                 return 0;
2554         }
2555
2556         if (!pol) {
2557                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2558                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2559                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2560                         return 0;
2561                 }
2562                 return 1;
2563         }
2564
2565         pol->curlft.use_time = get_seconds();
2566
2567         pols[0] = pol;
2568         npols++;
2569 #ifdef CONFIG_XFRM_SUB_POLICY
2570         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2571                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2572                                                     &fl, family,
2573                                                     XFRM_POLICY_IN);
2574                 if (pols[1]) {
2575                         if (IS_ERR(pols[1])) {
2576                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2577                                 return 0;
2578                         }
2579                         pols[1]->curlft.use_time = get_seconds();
2580                         npols++;
2581                 }
2582         }
2583 #endif
2584
2585         if (pol->action == XFRM_POLICY_ALLOW) {
2586                 struct sec_path *sp;
2587                 static struct sec_path dummy;
2588                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2589                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2590                 struct xfrm_tmpl **tpp = tp;
2591                 int ti = 0;
2592                 int i, k;
2593
2594                 if ((sp = skb->sp) == NULL)
2595                         sp = &dummy;
2596
2597                 for (pi = 0; pi < npols; pi++) {
2598                         if (pols[pi] != pol &&
2599                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2600                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2601                                 goto reject;
2602                         }
2603                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2604                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2605                                 goto reject_error;
2606                         }
2607                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2608                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2609                 }
2610                 xfrm_nr = ti;
2611                 if (npols > 1) {
2612                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2613                         tpp = stp;
2614                 }
2615
2616                 /* For each tunnel xfrm, find the first matching tmpl.
2617                  * For each tmpl before that, find corresponding xfrm.
2618                  * Order is _important_. Later we will implement
2619                  * some barriers, but at the moment barriers
2620                  * are implied between each two transformations.
2621                  */
2622                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2623                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2624                         if (k < 0) {
2625                                 if (k < -1)
2626                                         /* "-2 - errored_index" returned */
2627                                         xerr_idx = -(2+k);
2628                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2629                                 goto reject;
2630                         }
2631                 }
2632
2633                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2634                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2635                         goto reject;
2636                 }
2637
2638                 xfrm_pols_put(pols, npols);
2639                 return 1;
2640         }
2641         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2642
2643 reject:
2644         xfrm_secpath_reject(xerr_idx, skb, &fl);
2645 reject_error:
2646         xfrm_pols_put(pols, npols);
2647         return 0;
2648 }
2649 EXPORT_SYMBOL(__xfrm_policy_check);
2650
2651 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2652 {
2653         struct net *net = dev_net(skb->dev);
2654         struct flowi fl;
2655         struct dst_entry *dst;
2656         int res = 1;
2657
2658         if (xfrm_decode_session(skb, &fl, family) < 0) {
2659                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2660                 return 0;
2661         }
2662
2663         skb_dst_force(skb);
2664
2665         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2666         if (IS_ERR(dst)) {
2667                 res = 0;
2668                 dst = NULL;
2669         }
2670         skb_dst_set(skb, dst);
2671         return res;
2672 }
2673 EXPORT_SYMBOL(__xfrm_route_forward);
2674
2675 /* Optimize later using cookies and generation ids. */
2676
2677 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2678 {
2679         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2680          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2681          * get validated by dst_ops->check on every use.  We do this
2682          * because when a normal route referenced by an XFRM dst is
2683          * obsoleted we do not go looking around for all parent
2684          * referencing XFRM dsts so that we can invalidate them.  It
2685          * is just too much work.  Instead we make the checks here on
2686          * every use.  For example:
2687          *
2688          *      XFRM dst A --> IPv4 dst X
2689          *
2690          * X is the "xdst->route" of A (X is also the "dst->path" of A
2691          * in this example).  If X is marked obsolete, "A" will not
2692          * notice.  That's what we are validating here via the
2693          * stale_bundle() check.
2694          *
2695          * When a policy's bundle is pruned, we dst_free() the XFRM
2696          * dst which causes it's ->obsolete field to be set to
2697          * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2698          * this, we want to force a new route lookup.
2699          */
2700         if (dst->obsolete < 0 && !stale_bundle(dst))
2701                 return dst;
2702
2703         return NULL;
2704 }
2705
2706 static int stale_bundle(struct dst_entry *dst)
2707 {
2708         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2709 }
2710
2711 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2712 {
2713         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2714                 dst->dev = dev_net(dev)->loopback_dev;
2715                 dev_hold(dst->dev);
2716                 dev_put(dev);
2717         }
2718 }
2719 EXPORT_SYMBOL(xfrm_dst_ifdown);
2720
2721 static void xfrm_link_failure(struct sk_buff *skb)
2722 {
2723         /* Impossible. Such dst must be popped before reaches point of failure. */
2724 }
2725
2726 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2727 {
2728         if (dst) {
2729                 if (dst->obsolete) {
2730                         dst_release(dst);
2731                         dst = NULL;
2732                 }
2733         }
2734         return dst;
2735 }
2736
2737 void xfrm_garbage_collect(struct net *net)
2738 {
2739         flow_cache_flush(net);
2740 }
2741 EXPORT_SYMBOL(xfrm_garbage_collect);
2742
2743 static void xfrm_garbage_collect_deferred(struct net *net)
2744 {
2745         flow_cache_flush_deferred(net);
2746 }
2747
2748 static void xfrm_init_pmtu(struct dst_entry *dst)
2749 {
2750         do {
2751                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2752                 u32 pmtu, route_mtu_cached;
2753
2754                 pmtu = dst_mtu(dst->child);
2755                 xdst->child_mtu_cached = pmtu;
2756
2757                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2758
2759                 route_mtu_cached = dst_mtu(xdst->route);
2760                 xdst->route_mtu_cached = route_mtu_cached;
2761
2762                 if (pmtu > route_mtu_cached)
2763                         pmtu = route_mtu_cached;
2764
2765                 dst_metric_set(dst, RTAX_MTU, pmtu);
2766         } while ((dst = dst->next));
2767 }
2768
2769 /* Check that the bundle accepts the flow and its components are
2770  * still valid.
2771  */
2772
2773 static int xfrm_bundle_ok(struct xfrm_dst *first)
2774 {
2775         struct dst_entry *dst = &first->u.dst;
2776         struct xfrm_dst *last;
2777         u32 mtu;
2778
2779         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2780             (dst->dev && !netif_running(dst->dev)))
2781                 return 0;
2782
2783         if (dst->flags & DST_XFRM_QUEUE)
2784                 return 1;
2785
2786         last = NULL;
2787
2788         do {
2789                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2790
2791                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2792                         return 0;
2793                 if (xdst->xfrm_genid != dst->xfrm->genid)
2794                         return 0;
2795                 if (xdst->num_pols > 0 &&
2796                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2797                         return 0;
2798
2799                 mtu = dst_mtu(dst->child);
2800                 if (xdst->child_mtu_cached != mtu) {
2801                         last = xdst;
2802                         xdst->child_mtu_cached = mtu;
2803                 }
2804
2805                 if (!dst_check(xdst->route, xdst->route_cookie))
2806                         return 0;
2807                 mtu = dst_mtu(xdst->route);
2808                 if (xdst->route_mtu_cached != mtu) {
2809                         last = xdst;
2810                         xdst->route_mtu_cached = mtu;
2811                 }
2812
2813                 dst = dst->child;
2814         } while (dst->xfrm);
2815
2816         if (likely(!last))
2817                 return 1;
2818
2819         mtu = last->child_mtu_cached;
2820         for (;;) {
2821                 dst = &last->u.dst;
2822
2823                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2824                 if (mtu > last->route_mtu_cached)
2825                         mtu = last->route_mtu_cached;
2826                 dst_metric_set(dst, RTAX_MTU, mtu);
2827
2828                 if (last == first)
2829                         break;
2830
2831                 last = (struct xfrm_dst *)last->u.dst.next;
2832                 last->child_mtu_cached = mtu;
2833         }
2834
2835         return 1;
2836 }
2837
2838 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2839 {
2840         return dst_metric_advmss(dst->path);
2841 }
2842
2843 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2844 {
2845         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2846
2847         return mtu ? : dst_mtu(dst->path);
2848 }
2849
2850 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2851                                            struct sk_buff *skb,
2852                                            const void *daddr)
2853 {
2854         return dst->path->ops->neigh_lookup(dst, skb, daddr);
2855 }
2856
2857 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2858 {
2859         int err = 0;
2860         if (unlikely(afinfo == NULL))
2861                 return -EINVAL;
2862         if (unlikely(afinfo->family >= NPROTO))
2863                 return -EAFNOSUPPORT;
2864         spin_lock(&xfrm_policy_afinfo_lock);
2865         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2866                 err = -EEXIST;
2867         else {
2868                 struct dst_ops *dst_ops = afinfo->dst_ops;
2869                 if (likely(dst_ops->kmem_cachep == NULL))
2870                         dst_ops->kmem_cachep = xfrm_dst_cache;
2871                 if (likely(dst_ops->check == NULL))
2872                         dst_ops->check = xfrm_dst_check;
2873                 if (likely(dst_ops->default_advmss == NULL))
2874                         dst_ops->default_advmss = xfrm_default_advmss;
2875                 if (likely(dst_ops->mtu == NULL))
2876                         dst_ops->mtu = xfrm_mtu;
2877                 if (likely(dst_ops->negative_advice == NULL))
2878                         dst_ops->negative_advice = xfrm_negative_advice;
2879                 if (likely(dst_ops->link_failure == NULL))
2880                         dst_ops->link_failure = xfrm_link_failure;
2881                 if (likely(dst_ops->neigh_lookup == NULL))
2882                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2883                 if (likely(afinfo->garbage_collect == NULL))
2884                         afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2885                 rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
2886         }
2887         spin_unlock(&xfrm_policy_afinfo_lock);
2888
2889         return err;
2890 }
2891 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2892
2893 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2894 {
2895         int err = 0;
2896         if (unlikely(afinfo == NULL))
2897                 return -EINVAL;
2898         if (unlikely(afinfo->family >= NPROTO))
2899                 return -EAFNOSUPPORT;
2900         spin_lock(&xfrm_policy_afinfo_lock);
2901         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2902                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2903                         err = -EINVAL;
2904                 else
2905                         RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
2906                                          NULL);
2907         }
2908         spin_unlock(&xfrm_policy_afinfo_lock);
2909         if (!err) {
2910                 struct dst_ops *dst_ops = afinfo->dst_ops;
2911
2912                 synchronize_rcu();
2913
2914                 dst_ops->kmem_cachep = NULL;
2915                 dst_ops->check = NULL;
2916                 dst_ops->negative_advice = NULL;
2917                 dst_ops->link_failure = NULL;
2918                 afinfo->garbage_collect = NULL;
2919         }
2920         return err;
2921 }
2922 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2923
2924 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2925 {
2926         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2927
2928         switch (event) {
2929         case NETDEV_DOWN:
2930                 xfrm_garbage_collect(dev_net(dev));
2931         }
2932         return NOTIFY_DONE;
2933 }
2934
2935 static struct notifier_block xfrm_dev_notifier = {
2936         .notifier_call  = xfrm_dev_event,
2937 };
2938
2939 #ifdef CONFIG_XFRM_STATISTICS
2940 static int __net_init xfrm_statistics_init(struct net *net)
2941 {
2942         int rv;
2943         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2944         if (!net->mib.xfrm_statistics)
2945                 return -ENOMEM;
2946         rv = xfrm_proc_init(net);
2947         if (rv < 0)
2948                 free_percpu(net->mib.xfrm_statistics);
2949         return rv;
2950 }
2951
2952 static void xfrm_statistics_fini(struct net *net)
2953 {
2954         xfrm_proc_fini(net);
2955         free_percpu(net->mib.xfrm_statistics);
2956 }
2957 #else
2958 static int __net_init xfrm_statistics_init(struct net *net)
2959 {
2960         return 0;
2961 }
2962
2963 static void xfrm_statistics_fini(struct net *net)
2964 {
2965 }
2966 #endif
2967
2968 static int __net_init xfrm_policy_init(struct net *net)
2969 {
2970         unsigned int hmask, sz;
2971         int dir;
2972
2973         if (net_eq(net, &init_net))
2974                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2975                                            sizeof(struct xfrm_dst),
2976                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2977                                            NULL);
2978
2979         hmask = 8 - 1;
2980         sz = (hmask+1) * sizeof(struct hlist_head);
2981
2982         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2983         if (!net->xfrm.policy_byidx)
2984                 goto out_byidx;
2985         net->xfrm.policy_idx_hmask = hmask;
2986
2987         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2988                 struct xfrm_policy_hash *htab;
2989
2990                 net->xfrm.policy_count[dir] = 0;
2991                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2992                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2993
2994                 htab = &net->xfrm.policy_bydst[dir];
2995                 htab->table = xfrm_hash_alloc(sz);
2996                 if (!htab->table)
2997                         goto out_bydst;
2998                 htab->hmask = hmask;
2999                 htab->dbits4 = 32;
3000                 htab->sbits4 = 32;
3001                 htab->dbits6 = 128;
3002                 htab->sbits6 = 128;
3003         }
3004         net->xfrm.policy_hthresh.lbits4 = 32;
3005         net->xfrm.policy_hthresh.rbits4 = 32;
3006         net->xfrm.policy_hthresh.lbits6 = 128;
3007         net->xfrm.policy_hthresh.rbits6 = 128;
3008
3009         seqlock_init(&net->xfrm.policy_hthresh.lock);
3010
3011         INIT_LIST_HEAD(&net->xfrm.policy_all);
3012         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
3013         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
3014         if (net_eq(net, &init_net))
3015                 register_netdevice_notifier(&xfrm_dev_notifier);
3016         return 0;
3017
3018 out_bydst:
3019         for (dir--; dir >= 0; dir--) {
3020                 struct xfrm_policy_hash *htab;
3021
3022                 htab = &net->xfrm.policy_bydst[dir];
3023                 xfrm_hash_free(htab->table, sz);
3024         }
3025         xfrm_hash_free(net->xfrm.policy_byidx, sz);
3026 out_byidx:
3027         return -ENOMEM;
3028 }
3029
3030 static void xfrm_policy_fini(struct net *net)
3031 {
3032         unsigned int sz;
3033         int dir;
3034
3035         flush_work(&net->xfrm.policy_hash_work);
3036 #ifdef CONFIG_XFRM_SUB_POLICY
3037         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
3038 #endif
3039         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
3040
3041         WARN_ON(!list_empty(&net->xfrm.policy_all));
3042
3043         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
3044                 struct xfrm_policy_hash *htab;
3045
3046                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
3047
3048                 htab = &net->xfrm.policy_bydst[dir];
3049                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
3050                 WARN_ON(!hlist_empty(htab->table));
3051                 xfrm_hash_free(htab->table, sz);
3052         }
3053
3054         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
3055         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
3056         xfrm_hash_free(net->xfrm.policy_byidx, sz);
3057 }
3058
3059 static int __net_init xfrm_net_init(struct net *net)
3060 {
3061         int rv;
3062
3063         rv = xfrm_statistics_init(net);
3064         if (rv < 0)
3065                 goto out_statistics;
3066         rv = xfrm_state_init(net);
3067         if (rv < 0)
3068                 goto out_state;
3069         rv = xfrm_policy_init(net);
3070         if (rv < 0)
3071                 goto out_policy;
3072         rv = xfrm_sysctl_init(net);
3073         if (rv < 0)
3074                 goto out_sysctl;
3075         rv = flow_cache_init(net);
3076         if (rv < 0)
3077                 goto out;
3078
3079         /* Initialize the per-net locks here */
3080         spin_lock_init(&net->xfrm.xfrm_state_lock);
3081         spin_lock_init(&net->xfrm.xfrm_policy_lock);
3082         mutex_init(&net->xfrm.xfrm_cfg_mutex);
3083
3084         return 0;
3085
3086 out:
3087         xfrm_sysctl_fini(net);
3088 out_sysctl:
3089         xfrm_policy_fini(net);
3090 out_policy:
3091         xfrm_state_fini(net);
3092 out_state:
3093         xfrm_statistics_fini(net);
3094 out_statistics:
3095         return rv;
3096 }
3097
3098 static void __net_exit xfrm_net_exit(struct net *net)
3099 {
3100         flow_cache_fini(net);
3101         xfrm_sysctl_fini(net);
3102         xfrm_policy_fini(net);
3103         xfrm_state_fini(net);
3104         xfrm_statistics_fini(net);
3105 }
3106
3107 static struct pernet_operations __net_initdata xfrm_net_ops = {
3108         .init = xfrm_net_init,
3109         .exit = xfrm_net_exit,
3110 };
3111
3112 void __init xfrm_init(void)
3113 {
3114         register_pernet_subsys(&xfrm_net_ops);
3115         seqcount_init(&xfrm_policy_hash_generation);
3116         xfrm_input_init();
3117 }
3118
3119 #ifdef CONFIG_AUDITSYSCALL
3120 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3121                                          struct audit_buffer *audit_buf)
3122 {
3123         struct xfrm_sec_ctx *ctx = xp->security;
3124         struct xfrm_selector *sel = &xp->selector;
3125
3126         if (ctx)
3127                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3128                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3129
3130         switch (sel->family) {
3131         case AF_INET:
3132                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3133                 if (sel->prefixlen_s != 32)
3134                         audit_log_format(audit_buf, " src_prefixlen=%d",
3135                                          sel->prefixlen_s);
3136                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3137                 if (sel->prefixlen_d != 32)
3138                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3139                                          sel->prefixlen_d);
3140                 break;
3141         case AF_INET6:
3142                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3143                 if (sel->prefixlen_s != 128)
3144                         audit_log_format(audit_buf, " src_prefixlen=%d",
3145                                          sel->prefixlen_s);
3146                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3147                 if (sel->prefixlen_d != 128)
3148                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3149                                          sel->prefixlen_d);
3150                 break;
3151         }
3152 }
3153
3154 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3155 {
3156         struct audit_buffer *audit_buf;
3157
3158         audit_buf = xfrm_audit_start("SPD-add");
3159         if (audit_buf == NULL)
3160                 return;
3161         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3162         audit_log_format(audit_buf, " res=%u", result);
3163         xfrm_audit_common_policyinfo(xp, audit_buf);
3164         audit_log_end(audit_buf);
3165 }
3166 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3167
3168 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3169                               bool task_valid)
3170 {
3171         struct audit_buffer *audit_buf;
3172
3173         audit_buf = xfrm_audit_start("SPD-delete");
3174         if (audit_buf == NULL)
3175                 return;
3176         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3177         audit_log_format(audit_buf, " res=%u", result);
3178         xfrm_audit_common_policyinfo(xp, audit_buf);
3179         audit_log_end(audit_buf);
3180 }
3181 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3182 #endif
3183
3184 #ifdef CONFIG_XFRM_MIGRATE
3185 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3186                                         const struct xfrm_selector *sel_tgt)
3187 {
3188         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3189                 if (sel_tgt->family == sel_cmp->family &&
3190                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3191                                     sel_cmp->family) &&
3192                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3193                                     sel_cmp->family) &&
3194                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3195                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3196                         return true;
3197                 }
3198         } else {
3199                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3200                         return true;
3201                 }
3202         }
3203         return false;
3204 }
3205
3206 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3207                                                     u8 dir, u8 type, struct net *net)
3208 {
3209         struct xfrm_policy *pol, *ret = NULL;
3210         struct hlist_head *chain;
3211         u32 priority = ~0U;
3212
3213         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3214         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3215         hlist_for_each_entry(pol, chain, bydst) {
3216                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3217                     pol->type == type) {
3218                         ret = pol;
3219                         priority = ret->priority;
3220                         break;
3221                 }
3222         }
3223         chain = &net->xfrm.policy_inexact[dir];
3224         hlist_for_each_entry(pol, chain, bydst) {
3225                 if ((pol->priority >= priority) && ret)
3226                         break;
3227
3228                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3229                     pol->type == type) {
3230                         ret = pol;
3231                         break;
3232                 }
3233         }
3234
3235         xfrm_pol_hold(ret);
3236
3237         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3238
3239         return ret;
3240 }
3241
3242 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3243 {
3244         int match = 0;
3245
3246         if (t->mode == m->mode && t->id.proto == m->proto &&
3247             (m->reqid == 0 || t->reqid == m->reqid)) {
3248                 switch (t->mode) {
3249                 case XFRM_MODE_TUNNEL:
3250                 case XFRM_MODE_BEET:
3251                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3252                                             m->old_family) &&
3253                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3254                                             m->old_family)) {
3255                                 match = 1;
3256                         }
3257                         break;
3258                 case XFRM_MODE_TRANSPORT:
3259                         /* in case of transport mode, template does not store
3260                            any IP addresses, hence we just compare mode and
3261                            protocol */
3262                         match = 1;
3263                         break;
3264                 default:
3265                         break;
3266                 }
3267         }
3268         return match;
3269 }
3270
3271 /* update endpoint address(es) of template(s) */
3272 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3273                                struct xfrm_migrate *m, int num_migrate)
3274 {
3275         struct xfrm_migrate *mp;
3276         int i, j, n = 0;
3277
3278         write_lock_bh(&pol->lock);
3279         if (unlikely(pol->walk.dead)) {
3280                 /* target policy has been deleted */
3281                 write_unlock_bh(&pol->lock);
3282                 return -ENOENT;
3283         }
3284
3285         for (i = 0; i < pol->xfrm_nr; i++) {
3286                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3287                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3288                                 continue;
3289                         n++;
3290                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3291                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3292                                 continue;
3293                         /* update endpoints */
3294                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3295                                sizeof(pol->xfrm_vec[i].id.daddr));
3296                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3297                                sizeof(pol->xfrm_vec[i].saddr));
3298                         pol->xfrm_vec[i].encap_family = mp->new_family;
3299                         /* flush bundles */
3300                         atomic_inc(&pol->genid);
3301                 }
3302         }
3303
3304         write_unlock_bh(&pol->lock);
3305
3306         if (!n)
3307                 return -ENODATA;
3308
3309         return 0;
3310 }
3311
3312 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3313 {
3314         int i, j;
3315
3316         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3317                 return -EINVAL;
3318
3319         for (i = 0; i < num_migrate; i++) {
3320                 if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3321                                     m[i].old_family) &&
3322                     xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3323                                     m[i].old_family))
3324                         return -EINVAL;
3325                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3326                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3327                         return -EINVAL;
3328
3329                 /* check if there is any duplicated entry */
3330                 for (j = i + 1; j < num_migrate; j++) {
3331                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3332                                     sizeof(m[i].old_daddr)) &&
3333                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3334                                     sizeof(m[i].old_saddr)) &&
3335                             m[i].proto == m[j].proto &&
3336                             m[i].mode == m[j].mode &&
3337                             m[i].reqid == m[j].reqid &&
3338                             m[i].old_family == m[j].old_family)
3339                                 return -EINVAL;
3340                 }
3341         }
3342
3343         return 0;
3344 }
3345
3346 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3347                  struct xfrm_migrate *m, int num_migrate,
3348                  struct xfrm_kmaddress *k, struct net *net)
3349 {
3350         int i, err, nx_cur = 0, nx_new = 0;
3351         struct xfrm_policy *pol = NULL;
3352         struct xfrm_state *x, *xc;
3353         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3354         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3355         struct xfrm_migrate *mp;
3356
3357         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3358                 goto out;
3359
3360         /* Stage 1 - find policy */
3361         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3362                 err = -ENOENT;
3363                 goto out;
3364         }
3365
3366         /* Stage 2 - find and update state(s) */
3367         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3368                 if ((x = xfrm_migrate_state_find(mp, net))) {
3369                         x_cur[nx_cur] = x;
3370                         nx_cur++;
3371                         if ((xc = xfrm_state_migrate(x, mp))) {
3372                                 x_new[nx_new] = xc;
3373                                 nx_new++;
3374                         } else {
3375                                 err = -ENODATA;
3376                                 goto restore_state;
3377                         }
3378                 }
3379         }
3380
3381         /* Stage 3 - update policy */
3382         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3383                 goto restore_state;
3384
3385         /* Stage 4 - delete old state(s) */
3386         if (nx_cur) {
3387                 xfrm_states_put(x_cur, nx_cur);
3388                 xfrm_states_delete(x_cur, nx_cur);
3389         }
3390
3391         /* Stage 5 - announce */
3392         km_migrate(sel, dir, type, m, num_migrate, k);
3393
3394         xfrm_pol_put(pol);
3395
3396         return 0;
3397 out:
3398         return err;
3399
3400 restore_state:
3401         if (pol)
3402                 xfrm_pol_put(pol);
3403         if (nx_cur)
3404                 xfrm_states_put(x_cur, nx_cur);
3405         if (nx_new)
3406                 xfrm_states_delete(x_new, nx_new);
3407
3408         return err;
3409 }
3410 EXPORT_SYMBOL(xfrm_migrate);
3411 #endif