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 DEFINE_MUTEX(xfrm_cfg_mutex);
  43 EXPORT_SYMBOL(xfrm_cfg_mutex);
  44
  45 static DEFINE_SPINLOCK(xfrm_policy_sk_bundle_lock);
  46 static struct dst_entry *xfrm_policy_sk_bundles;
  47 static DEFINE_RWLOCK(xfrm_policy_lock);
  48
  49 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
  50 static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
  51                                                 __read_mostly;
  52
  53 static struct kmem_cache *xfrm_dst_cache __read_mostly;
  54
  55 static void xfrm_init_pmtu(struct dst_entry *dst);
  56 static int stale_bundle(struct dst_entry *dst);
  57 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
  58 static void xfrm_policy_queue_process(unsigned long arg);
  59
  60 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
  61                                                 int dir);
  62
  63 static inline bool
  64 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  65 {
  66         const struct flowi4 *fl4 = &fl->u.ip4;
  67
  68         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
  69                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
  70                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
  71                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
  72                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
  73                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
  74 }
  75
  76 static inline bool
  77 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  78 {
  79         const struct flowi6 *fl6 = &fl->u.ip6;
  80
  81         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
  82                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
  83                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
  84                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
  85                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
  86                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
  87 }
  88
  89 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
  90                          unsigned short family)
  91 {
  92         switch (family) {
  93         case AF_INET:
  94                 return __xfrm4_selector_match(sel, fl);
  95         case AF_INET6:
  96                 return __xfrm6_selector_match(sel, fl);
  97         }
  98         return false;
  99 }
 100
 101 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 102 {
 103         struct xfrm_policy_afinfo *afinfo;
 104
 105         if (unlikely(family >= NPROTO))
 106                 return NULL;
 107         rcu_read_lock();
 108         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 109         if (unlikely(!afinfo))
 110                 rcu_read_unlock();
 111         return afinfo;
 112 }
 113
 114 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
 115 {
 116         rcu_read_unlock();
 117 }
 118
 119 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
 120                                                   const xfrm_address_t *saddr,
 121                                                   const xfrm_address_t *daddr,
 122                                                   int family)
 123 {
 124         struct xfrm_policy_afinfo *afinfo;
 125         struct dst_entry *dst;
 126
 127         afinfo = xfrm_policy_get_afinfo(family);
 128         if (unlikely(afinfo == NULL))
 129                 return ERR_PTR(-EAFNOSUPPORT);
 130
 131         dst = afinfo->dst_lookup(net, tos, saddr, daddr);
 132
 133         xfrm_policy_put_afinfo(afinfo);
 134
 135         return dst;
 136 }
 137
 138 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
 139                                                 xfrm_address_t *prev_saddr,
 140                                                 xfrm_address_t *prev_daddr,
 141                                                 int family)
 142 {
 143         struct net *net = xs_net(x);
 144         xfrm_address_t *saddr = &x->props.saddr;
 145         xfrm_address_t *daddr = &x->id.daddr;
 146         struct dst_entry *dst;
 147
 148         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 149                 saddr = x->coaddr;
 150                 daddr = prev_daddr;
 151         }
 152         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 153                 saddr = prev_saddr;
 154                 daddr = x->coaddr;
 155         }
 156
 157         dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
 158
 159         if (!IS_ERR(dst)) {
 160                 if (prev_saddr != saddr)
 161                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 162                 if (prev_daddr != daddr)
 163                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 164         }
 165
 166         return dst;
 167 }
 168
 169 static inline unsigned long make_jiffies(long secs)
 170 {
 171         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 172                 return MAX_SCHEDULE_TIMEOUT-1;
 173         else
 174                 return secs*HZ;
 175 }
 176
 177 static void xfrm_policy_timer(unsigned long data)
 178 {
 179         struct xfrm_policy *xp = (struct xfrm_policy*)data;
 180         unsigned long now = get_seconds();
 181         long next = LONG_MAX;
 182         int warn = 0;
 183         int dir;
 184
 185         read_lock(&xp->lock);
 186
 187         if (unlikely(xp->walk.dead))
 188                 goto out;
 189
 190         dir = xfrm_policy_id2dir(xp->index);
 191
 192         if (xp->lft.hard_add_expires_seconds) {
 193                 long tmo = xp->lft.hard_add_expires_seconds +
 194                         xp->curlft.add_time - now;
 195                 if (tmo <= 0)
 196                         goto expired;
 197                 if (tmo < next)
 198                         next = tmo;
 199         }
 200         if (xp->lft.hard_use_expires_seconds) {
 201                 long tmo = xp->lft.hard_use_expires_seconds +
 202                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 203                 if (tmo <= 0)
 204                         goto expired;
 205                 if (tmo < next)
 206                         next = tmo;
 207         }
 208         if (xp->lft.soft_add_expires_seconds) {
 209                 long tmo = xp->lft.soft_add_expires_seconds +
 210                         xp->curlft.add_time - now;
 211                 if (tmo <= 0) {
 212                         warn = 1;
 213                         tmo = XFRM_KM_TIMEOUT;
 214                 }
 215                 if (tmo < next)
 216                         next = tmo;
 217         }
 218         if (xp->lft.soft_use_expires_seconds) {
 219                 long tmo = xp->lft.soft_use_expires_seconds +
 220                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 221                 if (tmo <= 0) {
 222                         warn = 1;
 223                         tmo = XFRM_KM_TIMEOUT;
 224                 }
 225                 if (tmo < next)
 226                         next = tmo;
 227         }
 228
 229         if (warn)
 230                 km_policy_expired(xp, dir, 0, 0);
 231         if (next != LONG_MAX &&
 232             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 233                 xfrm_pol_hold(xp);
 234
 235 out:
 236         read_unlock(&xp->lock);
 237         xfrm_pol_put(xp);
 238         return;
 239
 240 expired:
 241         read_unlock(&xp->lock);
 242         if (!xfrm_policy_delete(xp, dir))
 243                 km_policy_expired(xp, dir, 1, 0);
 244         xfrm_pol_put(xp);
 245 }
 246
 247 static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
 248 {
 249         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 250
 251         if (unlikely(pol->walk.dead))
 252                 flo = NULL;
 253         else
 254                 xfrm_pol_hold(pol);
 255
 256         return flo;
 257 }
 258
 259 static int xfrm_policy_flo_check(struct flow_cache_object *flo)
 260 {
 261         struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 262
 263         return !pol->walk.dead;
 264 }
 265
 266 static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
 267 {
 268         xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
 269 }
 270
 271 static const struct flow_cache_ops xfrm_policy_fc_ops = {
 272         .get = xfrm_policy_flo_get,
 273         .check = xfrm_policy_flo_check,
 274         .delete = xfrm_policy_flo_delete,
 275 };
 276
 277 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 278  * SPD calls.
 279  */
 280
 281 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 282 {
 283         struct xfrm_policy *policy;
 284
 285         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 286
 287         if (policy) {
 288                 write_pnet(&policy->xp_net, net);
 289                 INIT_LIST_HEAD(&policy->walk.all);
 290                 INIT_HLIST_NODE(&policy->bydst);
 291                 INIT_HLIST_NODE(&policy->byidx);
 292                 rwlock_init(&policy->lock);
 293                 atomic_set(&policy->refcnt, 1);
 294                 skb_queue_head_init(&policy->polq.hold_queue);
 295                 setup_timer(&policy->timer, xfrm_policy_timer,
 296                                 (unsigned long)policy);
 297                 setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
 298                             (unsigned long)policy);
 299                 policy->flo.ops = &xfrm_policy_fc_ops;
 300         }
 301         return policy;
 302 }
 303 EXPORT_SYMBOL(xfrm_policy_alloc);
 304
 305 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 306
 307 void xfrm_policy_destroy(struct xfrm_policy *policy)
 308 {
 309         BUG_ON(!policy->walk.dead);
 310
 311         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 312                 BUG();
 313
 314         security_xfrm_policy_free(policy->security);
 315         kfree(policy);
 316 }
 317 EXPORT_SYMBOL(xfrm_policy_destroy);
 318
 319 static void xfrm_queue_purge(struct sk_buff_head *list)
 320 {
 321         struct sk_buff *skb;
 322
 323         while ((skb = skb_dequeue(list)) != NULL)
 324                 kfree_skb(skb);
 325 }
 326
 327 /* Rule must be locked. Release descentant resources, announce
 328  * entry dead. The rule must be unlinked from lists to the moment.
 329  */
 330
 331 static void xfrm_policy_kill(struct xfrm_policy *policy)
 332 {
 333         policy->walk.dead = 1;
 334
 335         atomic_inc(&policy->genid);
 336
 337         if (del_timer(&policy->polq.hold_timer))
 338                 xfrm_pol_put(policy);
 339         xfrm_queue_purge(&policy->polq.hold_queue);
 340
 341         if (del_timer(&policy->timer))
 342                 xfrm_pol_put(policy);
 343
 344         xfrm_pol_put(policy);
 345 }
 346
 347 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 348
 349 static inline unsigned int idx_hash(struct net *net, u32 index)
 350 {
 351         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 352 }
 353
 354 static struct hlist_head *policy_hash_bysel(struct net *net,
 355                                             const struct xfrm_selector *sel,
 356                                             unsigned short family, int dir)
 357 {
 358         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 359         unsigned int hash = __sel_hash(sel, family, hmask);
 360
 361         return (hash == hmask + 1 ?
 362                 &net->xfrm.policy_inexact[dir] :
 363                 net->xfrm.policy_bydst[dir].table + hash);
 364 }
 365
 366 static struct hlist_head *policy_hash_direct(struct net *net,
 367                                              const xfrm_address_t *daddr,
 368                                              const xfrm_address_t *saddr,
 369                                              unsigned short family, int dir)
 370 {
 371         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 372         unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
 373
 374         return net->xfrm.policy_bydst[dir].table + hash;
 375 }
 376
 377 static void xfrm_dst_hash_transfer(struct hlist_head *list,
 378                                    struct hlist_head *ndsttable,
 379                                    unsigned int nhashmask)
 380 {
 381         struct hlist_node *tmp, *entry0 = NULL;
 382         struct xfrm_policy *pol;
 383         unsigned int h0 = 0;
 384
 385 redo:
 386         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 387                 unsigned int h;
 388
 389                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 390                                 pol->family, nhashmask);
 391                 if (!entry0) {
 392                         hlist_del(&pol->bydst);
 393                         hlist_add_head(&pol->bydst, ndsttable+h);
 394                         h0 = h;
 395                 } else {
 396                         if (h != h0)
 397                                 continue;
 398                         hlist_del(&pol->bydst);
 399                         hlist_add_after(entry0, &pol->bydst);
 400                 }
 401                 entry0 = &pol->bydst;
 402         }
 403         if (!hlist_empty(list)) {
 404                 entry0 = NULL;
 405                 goto redo;
 406         }
 407 }
 408
 409 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 410                                    struct hlist_head *nidxtable,
 411                                    unsigned int nhashmask)
 412 {
 413         struct hlist_node *tmp;
 414         struct xfrm_policy *pol;
 415
 416         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 417                 unsigned int h;
 418
 419                 h = __idx_hash(pol->index, nhashmask);
 420                 hlist_add_head(&pol->byidx, nidxtable+h);
 421         }
 422 }
 423
 424 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 425 {
 426         return ((old_hmask + 1) << 1) - 1;
 427 }
 428
 429 static void xfrm_bydst_resize(struct net *net, int dir)
 430 {
 431         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 432         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 433         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 434         struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
 435         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 436         int i;
 437
 438         if (!ndst)
 439                 return;
 440
 441         write_lock_bh(&xfrm_policy_lock);
 442
 443         for (i = hmask; i >= 0; i--)
 444                 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
 445
 446         net->xfrm.policy_bydst[dir].table = ndst;
 447         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 448
 449         write_unlock_bh(&xfrm_policy_lock);
 450
 451         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 452 }
 453
 454 static void xfrm_byidx_resize(struct net *net, int total)
 455 {
 456         unsigned int hmask = net->xfrm.policy_idx_hmask;
 457         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 458         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 459         struct hlist_head *oidx = net->xfrm.policy_byidx;
 460         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 461         int i;
 462
 463         if (!nidx)
 464                 return;
 465
 466         write_lock_bh(&xfrm_policy_lock);
 467
 468         for (i = hmask; i >= 0; i--)
 469                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 470
 471         net->xfrm.policy_byidx = nidx;
 472         net->xfrm.policy_idx_hmask = nhashmask;
 473
 474         write_unlock_bh(&xfrm_policy_lock);
 475
 476         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 477 }
 478
 479 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 480 {
 481         unsigned int cnt = net->xfrm.policy_count[dir];
 482         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 483
 484         if (total)
 485                 *total += cnt;
 486
 487         if ((hmask + 1) < xfrm_policy_hashmax &&
 488             cnt > hmask)
 489                 return 1;
 490
 491         return 0;
 492 }
 493
 494 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 495 {
 496         unsigned int hmask = net->xfrm.policy_idx_hmask;
 497
 498         if ((hmask + 1) < xfrm_policy_hashmax &&
 499             total > hmask)
 500                 return 1;
 501
 502         return 0;
 503 }
 504
 505 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 506 {
 507         read_lock_bh(&xfrm_policy_lock);
 508         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 509         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 510         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 511         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 512         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 513         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 514         si->spdhcnt = net->xfrm.policy_idx_hmask;
 515         si->spdhmcnt = xfrm_policy_hashmax;
 516         read_unlock_bh(&xfrm_policy_lock);
 517 }
 518 EXPORT_SYMBOL(xfrm_spd_getinfo);
 519
 520 static DEFINE_MUTEX(hash_resize_mutex);
 521 static void xfrm_hash_resize(struct work_struct *work)
 522 {
 523         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 524         int dir, total;
 525
 526         mutex_lock(&hash_resize_mutex);
 527
 528         total = 0;
 529         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
 530                 if (xfrm_bydst_should_resize(net, dir, &total))
 531                         xfrm_bydst_resize(net, dir);
 532         }
 533         if (xfrm_byidx_should_resize(net, total))
 534                 xfrm_byidx_resize(net, total);
 535
 536         mutex_unlock(&hash_resize_mutex);
 537 }
 538
 539 /* Generate new index... KAME seems to generate them ordered by cost
 540  * of an absolute inpredictability of ordering of rules. This will not pass. */
 541 static u32 xfrm_gen_index(struct net *net, int dir)
 542 {
 543         static u32 idx_generator;
 544
 545         for (;;) {
 546                 struct hlist_head *list;
 547                 struct xfrm_policy *p;
 548                 u32 idx;
 549                 int found;
 550
 551                 idx = (idx_generator | dir);
 552                 idx_generator += 8;
 553                 if (idx == 0)
 554                         idx = 8;
 555                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 556                 found = 0;
 557                 hlist_for_each_entry(p, list, byidx) {
 558                         if (p->index == idx) {
 559                                 found = 1;
 560                                 break;
 561                         }
 562                 }
 563                 if (!found)
 564                         return idx;
 565         }
 566 }
 567
 568 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 569 {
 570         u32 *p1 = (u32 *) s1;
 571         u32 *p2 = (u32 *) s2;
 572         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 573         int i;
 574
 575         for (i = 0; i < len; i++) {
 576                 if (p1[i] != p2[i])
 577                         return 1;
 578         }
 579
 580         return 0;
 581 }
 582
 583 static void xfrm_policy_requeue(struct xfrm_policy *old,
 584                                 struct xfrm_policy *new)
 585 {
 586         struct xfrm_policy_queue *pq = &old->polq;
 587         struct sk_buff_head list;
 588
 589         __skb_queue_head_init(&list);
 590
 591         spin_lock_bh(&pq->hold_queue.lock);
 592         skb_queue_splice_init(&pq->hold_queue, &list);
 593         if (del_timer(&pq->hold_timer))
 594                 xfrm_pol_put(old);
 595         spin_unlock_bh(&pq->hold_queue.lock);
 596
 597         if (skb_queue_empty(&list))
 598                 return;
 599
 600         pq = &new->polq;
 601
 602         spin_lock_bh(&pq->hold_queue.lock);
 603         skb_queue_splice(&list, &pq->hold_queue);
 604         pq->timeout = XFRM_QUEUE_TMO_MIN;
 605         if (!mod_timer(&pq->hold_timer, jiffies))
 606                 xfrm_pol_hold(new);
 607         spin_unlock_bh(&pq->hold_queue.lock);
 608 }
 609
 610 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
 611                                    struct xfrm_policy *pol)
 612 {
 613         u32 mark = policy->mark.v & policy->mark.m;
 614
 615         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
 616                 return true;
 617
 618         if ((mark & pol->mark.m) == pol->mark.v &&
 619             policy->priority == pol->priority)
 620                 return true;
 621
 622         return false;
 623 }
 624
 625 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 626 {
 627         struct net *net = xp_net(policy);
 628         struct xfrm_policy *pol;
 629         struct xfrm_policy *delpol;
 630         struct hlist_head *chain;
 631         struct hlist_node *newpos;
 632
 633         write_lock_bh(&xfrm_policy_lock);
 634         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 635         delpol = NULL;
 636         newpos = NULL;
 637         hlist_for_each_entry(pol, chain, bydst) {
 638                 if (pol->type == policy->type &&
 639                     !selector_cmp(&pol->selector, &policy->selector) &&
 640                     xfrm_policy_mark_match(policy, pol) &&
 641                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 642                     !WARN_ON(delpol)) {
 643                         if (excl) {
 644                                 write_unlock_bh(&xfrm_policy_lock);
 645                                 return -EEXIST;
 646                         }
 647                         delpol = pol;
 648                         if (policy->priority > pol->priority)
 649                                 continue;
 650                 } else if (policy->priority >= pol->priority) {
 651                         newpos = &pol->bydst;
 652                         continue;
 653                 }
 654                 if (delpol)
 655                         break;
 656         }
 657         if (newpos)
 658                 hlist_add_after(newpos, &policy->bydst);
 659         else
 660                 hlist_add_head(&policy->bydst, chain);
 661         xfrm_pol_hold(policy);
 662         net->xfrm.policy_count[dir]++;
 663         atomic_inc(&flow_cache_genid);
 664
 665         /* After previous checking, family can either be AF_INET or AF_INET6 */
 666         if (policy->family == AF_INET)
 667                 rt_genid_bump_ipv4(net);
 668         else
 669                 rt_genid_bump_ipv6(net);
 670
 671         if (delpol) {
 672                 xfrm_policy_requeue(delpol, policy);
 673                 __xfrm_policy_unlink(delpol, dir);
 674         }
 675         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir);
 676         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 677         policy->curlft.add_time = get_seconds();
 678         policy->curlft.use_time = 0;
 679         if (!mod_timer(&policy->timer, jiffies + HZ))
 680                 xfrm_pol_hold(policy);
 681         list_add(&policy->walk.all, &net->xfrm.policy_all);
 682         write_unlock_bh(&xfrm_policy_lock);
 683
 684         if (delpol)
 685                 xfrm_policy_kill(delpol);
 686         else if (xfrm_bydst_should_resize(net, dir, NULL))
 687                 schedule_work(&net->xfrm.policy_hash_work);
 688
 689         return 0;
 690 }
 691 EXPORT_SYMBOL(xfrm_policy_insert);
 692
 693 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
 694                                           int dir, struct xfrm_selector *sel,
 695                                           struct xfrm_sec_ctx *ctx, int delete,
 696                                           int *err)
 697 {
 698         struct xfrm_policy *pol, *ret;
 699         struct hlist_head *chain;
 700
 701         *err = 0;
 702         write_lock_bh(&xfrm_policy_lock);
 703         chain = policy_hash_bysel(net, sel, sel->family, dir);
 704         ret = NULL;
 705         hlist_for_each_entry(pol, chain, bydst) {
 706                 if (pol->type == type &&
 707                     (mark & pol->mark.m) == pol->mark.v &&
 708                     !selector_cmp(sel, &pol->selector) &&
 709                     xfrm_sec_ctx_match(ctx, pol->security)) {
 710                         xfrm_pol_hold(pol);
 711                         if (delete) {
 712                                 *err = security_xfrm_policy_delete(
 713                                                                 pol->security);
 714                                 if (*err) {
 715                                         write_unlock_bh(&xfrm_policy_lock);
 716                                         return pol;
 717                                 }
 718                                 __xfrm_policy_unlink(pol, dir);
 719                         }
 720                         ret = pol;
 721                         break;
 722                 }
 723         }
 724         write_unlock_bh(&xfrm_policy_lock);
 725
 726         if (ret && delete)
 727                 xfrm_policy_kill(ret);
 728         return ret;
 729 }
 730 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 731
 732 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
 733                                      int dir, u32 id, int delete, int *err)
 734 {
 735         struct xfrm_policy *pol, *ret;
 736         struct hlist_head *chain;
 737
 738         *err = -ENOENT;
 739         if (xfrm_policy_id2dir(id) != dir)
 740                 return NULL;
 741
 742         *err = 0;
 743         write_lock_bh(&xfrm_policy_lock);
 744         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 745         ret = NULL;
 746         hlist_for_each_entry(pol, chain, byidx) {
 747                 if (pol->type == type && pol->index == id &&
 748                     (mark & pol->mark.m) == pol->mark.v) {
 749                         xfrm_pol_hold(pol);
 750                         if (delete) {
 751                                 *err = security_xfrm_policy_delete(
 752                                                                 pol->security);
 753                                 if (*err) {
 754                                         write_unlock_bh(&xfrm_policy_lock);
 755                                         return pol;
 756                                 }
 757                                 __xfrm_policy_unlink(pol, dir);
 758                         }
 759                         ret = pol;
 760                         break;
 761                 }
 762         }
 763         write_unlock_bh(&xfrm_policy_lock);
 764
 765         if (ret && delete)
 766                 xfrm_policy_kill(ret);
 767         return ret;
 768 }
 769 EXPORT_SYMBOL(xfrm_policy_byid);
 770
 771 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 772 static inline int
 773 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
 774 {
 775         int dir, err = 0;
 776
 777         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 778                 struct xfrm_policy *pol;
 779                 int i;
 780
 781                 hlist_for_each_entry(pol,
 782                                      &net->xfrm.policy_inexact[dir], bydst) {
 783                         if (pol->type != type)
 784                                 continue;
 785                         err = security_xfrm_policy_delete(pol->security);
 786                         if (err) {
 787                                 xfrm_audit_policy_delete(pol, 0,
 788                                                          audit_info->loginuid,
 789                                                          audit_info->sessionid,
 790                                                          audit_info->secid);
 791                                 return err;
 792                         }
 793                 }
 794                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 795                         hlist_for_each_entry(pol,
 796                                              net->xfrm.policy_bydst[dir].table + i,
 797                                              bydst) {
 798                                 if (pol->type != type)
 799                                         continue;
 800                                 err = security_xfrm_policy_delete(
 801                                                                 pol->security);
 802                                 if (err) {
 803                                         xfrm_audit_policy_delete(pol, 0,
 804                                                         audit_info->loginuid,
 805                                                         audit_info->sessionid,
 806                                                         audit_info->secid);
 807                                         return err;
 808                                 }
 809                         }
 810                 }
 811         }
 812         return err;
 813 }
 814 #else
 815 static inline int
 816 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
 817 {
 818         return 0;
 819 }
 820 #endif
 821
 822 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info)
 823 {
 824         int dir, err = 0, cnt = 0;
 825
 826         write_lock_bh(&xfrm_policy_lock);
 827
 828         err = xfrm_policy_flush_secctx_check(net, type, audit_info);
 829         if (err)
 830                 goto out;
 831
 832         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 833                 struct xfrm_policy *pol;
 834                 int i;
 835
 836         again1:
 837                 hlist_for_each_entry(pol,
 838                                      &net->xfrm.policy_inexact[dir], bydst) {
 839                         if (pol->type != type)
 840                                 continue;
 841                         __xfrm_policy_unlink(pol, dir);
 842                         write_unlock_bh(&xfrm_policy_lock);
 843                         cnt++;
 844
 845                         xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
 846                                                  audit_info->sessionid,
 847                                                  audit_info->secid);
 848
 849                         xfrm_policy_kill(pol);
 850
 851                         write_lock_bh(&xfrm_policy_lock);
 852                         goto again1;
 853                 }
 854
 855                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 856         again2:
 857                         hlist_for_each_entry(pol,
 858                                              net->xfrm.policy_bydst[dir].table + i,
 859                                              bydst) {
 860                                 if (pol->type != type)
 861                                         continue;
 862                                 __xfrm_policy_unlink(pol, dir);
 863                                 write_unlock_bh(&xfrm_policy_lock);
 864                                 cnt++;
 865
 866                                 xfrm_audit_policy_delete(pol, 1,
 867                                                          audit_info->loginuid,
 868                                                          audit_info->sessionid,
 869                                                          audit_info->secid);
 870                                 xfrm_policy_kill(pol);
 871
 872                                 write_lock_bh(&xfrm_policy_lock);
 873                                 goto again2;
 874                         }
 875                 }
 876
 877         }
 878         if (!cnt)
 879                 err = -ESRCH;
 880 out:
 881         write_unlock_bh(&xfrm_policy_lock);
 882         return err;
 883 }
 884 EXPORT_SYMBOL(xfrm_policy_flush);
 885
 886 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 887                      int (*func)(struct xfrm_policy *, int, int, void*),
 888                      void *data)
 889 {
 890         struct xfrm_policy *pol;
 891         struct xfrm_policy_walk_entry *x;
 892         int error = 0;
 893
 894         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
 895             walk->type != XFRM_POLICY_TYPE_ANY)
 896                 return -EINVAL;
 897
 898         if (list_empty(&walk->walk.all) && walk->seq != 0)
 899                 return 0;
 900
 901         write_lock_bh(&xfrm_policy_lock);
 902         if (list_empty(&walk->walk.all))
 903                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
 904         else
 905                 x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
 906         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
 907                 if (x->dead)
 908                         continue;
 909                 pol = container_of(x, struct xfrm_policy, walk);
 910                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
 911                     walk->type != pol->type)
 912                         continue;
 913                 error = func(pol, xfrm_policy_id2dir(pol->index),
 914                              walk->seq, data);
 915                 if (error) {
 916                         list_move_tail(&walk->walk.all, &x->all);
 917                         goto out;
 918                 }
 919                 walk->seq++;
 920         }
 921         if (walk->seq == 0) {
 922                 error = -ENOENT;
 923                 goto out;
 924         }
 925         list_del_init(&walk->walk.all);
 926 out:
 927         write_unlock_bh(&xfrm_policy_lock);
 928         return error;
 929 }
 930 EXPORT_SYMBOL(xfrm_policy_walk);
 931
 932 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
 933 {
 934         INIT_LIST_HEAD(&walk->walk.all);
 935         walk->walk.dead = 1;
 936         walk->type = type;
 937         walk->seq = 0;
 938 }
 939 EXPORT_SYMBOL(xfrm_policy_walk_init);
 940
 941 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk)
 942 {
 943         if (list_empty(&walk->walk.all))
 944                 return;
 945
 946         write_lock_bh(&xfrm_policy_lock);
 947         list_del(&walk->walk.all);
 948         write_unlock_bh(&xfrm_policy_lock);
 949 }
 950 EXPORT_SYMBOL(xfrm_policy_walk_done);
 951
 952 /*
 953  * Find policy to apply to this flow.
 954  *
 955  * Returns 0 if policy found, else an -errno.
 956  */
 957 static int xfrm_policy_match(const struct xfrm_policy *pol,
 958                              const struct flowi *fl,
 959                              u8 type, u16 family, int dir)
 960 {
 961         const struct xfrm_selector *sel = &pol->selector;
 962         int ret = -ESRCH;
 963         bool match;
 964
 965         if (pol->family != family ||
 966             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
 967             pol->type != type)
 968                 return ret;
 969
 970         match = xfrm_selector_match(sel, fl, family);
 971         if (match)
 972                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
 973                                                   dir);
 974
 975         return ret;
 976 }
 977
 978 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 979                                                      const struct flowi *fl,
 980                                                      u16 family, u8 dir)
 981 {
 982         int err;
 983         struct xfrm_policy *pol, *ret;
 984         const xfrm_address_t *daddr, *saddr;
 985         struct hlist_head *chain;
 986         u32 priority = ~0U;
 987
 988         daddr = xfrm_flowi_daddr(fl, family);
 989         saddr = xfrm_flowi_saddr(fl, family);
 990         if (unlikely(!daddr || !saddr))
 991                 return NULL;
 992
 993         read_lock_bh(&xfrm_policy_lock);
 994         chain = policy_hash_direct(net, daddr, saddr, family, dir);
 995         ret = NULL;
 996         hlist_for_each_entry(pol, chain, bydst) {
 997                 err = xfrm_policy_match(pol, fl, type, family, dir);
 998                 if (err) {
 999                         if (err == -ESRCH)
1000                                 continue;
1001                         else {
1002                                 ret = ERR_PTR(err);
1003                                 goto fail;
1004                         }
1005                 } else {
1006                         ret = pol;
1007                         priority = ret->priority;
1008                         break;
1009                 }
1010         }
1011         chain = &net->xfrm.policy_inexact[dir];
1012         hlist_for_each_entry(pol, chain, bydst) {
1013                 err = xfrm_policy_match(pol, fl, type, family, dir);
1014                 if (err) {
1015                         if (err == -ESRCH)
1016                                 continue;
1017                         else {
1018                                 ret = ERR_PTR(err);
1019                                 goto fail;
1020                         }
1021                 } else if (pol->priority < priority) {
1022                         ret = pol;
1023                         break;
1024                 }
1025         }
1026         if (ret)
1027                 xfrm_pol_hold(ret);
1028 fail:
1029         read_unlock_bh(&xfrm_policy_lock);
1030
1031         return ret;
1032 }
1033
1034 static struct xfrm_policy *
1035 __xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1036 {
1037 #ifdef CONFIG_XFRM_SUB_POLICY
1038         struct xfrm_policy *pol;
1039
1040         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1041         if (pol != NULL)
1042                 return pol;
1043 #endif
1044         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1045 }
1046
1047 static int flow_to_policy_dir(int dir)
1048 {
1049         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1050             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1051             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1052                 return dir;
1053
1054         switch (dir) {
1055         default:
1056         case FLOW_DIR_IN:
1057                 return XFRM_POLICY_IN;
1058         case FLOW_DIR_OUT:
1059                 return XFRM_POLICY_OUT;
1060         case FLOW_DIR_FWD:
1061                 return XFRM_POLICY_FWD;
1062         }
1063 }
1064
1065 static struct flow_cache_object *
1066 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
1067                    u8 dir, struct flow_cache_object *old_obj, void *ctx)
1068 {
1069         struct xfrm_policy *pol;
1070
1071         if (old_obj)
1072                 xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
1073
1074         pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
1075         if (IS_ERR_OR_NULL(pol))
1076                 return ERR_CAST(pol);
1077
1078         /* Resolver returns two references:
1079          * one for cache and one for caller of flow_cache_lookup() */
1080         xfrm_pol_hold(pol);
1081
1082         return &pol->flo;
1083 }
1084
1085 static inline int policy_to_flow_dir(int dir)
1086 {
1087         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1088             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1089             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1090                 return dir;
1091         switch (dir) {
1092         default:
1093         case XFRM_POLICY_IN:
1094                 return FLOW_DIR_IN;
1095         case XFRM_POLICY_OUT:
1096                 return FLOW_DIR_OUT;
1097         case XFRM_POLICY_FWD:
1098                 return FLOW_DIR_FWD;
1099         }
1100 }
1101
1102 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
1103                                                  const struct flowi *fl)
1104 {
1105         struct xfrm_policy *pol;
1106
1107         read_lock_bh(&xfrm_policy_lock);
1108         if ((pol = sk->sk_policy[dir]) != NULL) {
1109                 bool match = xfrm_selector_match(&pol->selector, fl,
1110                                                  sk->sk_family);
1111                 int err = 0;
1112
1113                 if (match) {
1114                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1115                                 pol = NULL;
1116                                 goto out;
1117                         }
1118                         err = security_xfrm_policy_lookup(pol->security,
1119                                                       fl->flowi_secid,
1120                                                       policy_to_flow_dir(dir));
1121                         if (!err)
1122                                 xfrm_pol_hold(pol);
1123                         else if (err == -ESRCH)
1124                                 pol = NULL;
1125                         else
1126                                 pol = ERR_PTR(err);
1127                 } else
1128                         pol = NULL;
1129         }
1130 out:
1131         read_unlock_bh(&xfrm_policy_lock);
1132         return pol;
1133 }
1134
1135 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1136 {
1137         struct net *net = xp_net(pol);
1138         struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1139                                                      pol->family, dir);
1140
1141         list_add(&pol->walk.all, &net->xfrm.policy_all);
1142         hlist_add_head(&pol->bydst, chain);
1143         hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1144         net->xfrm.policy_count[dir]++;
1145         xfrm_pol_hold(pol);
1146
1147         if (xfrm_bydst_should_resize(net, dir, NULL))
1148                 schedule_work(&net->xfrm.policy_hash_work);
1149 }
1150
1151 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1152                                                 int dir)
1153 {
1154         struct net *net = xp_net(pol);
1155
1156         if (hlist_unhashed(&pol->bydst))
1157                 return NULL;
1158
1159         hlist_del(&pol->bydst);
1160         hlist_del(&pol->byidx);
1161         list_del(&pol->walk.all);
1162         net->xfrm.policy_count[dir]--;
1163
1164         return pol;
1165 }
1166
1167 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1168 {
1169         write_lock_bh(&xfrm_policy_lock);
1170         pol = __xfrm_policy_unlink(pol, dir);
1171         write_unlock_bh(&xfrm_policy_lock);
1172         if (pol) {
1173                 xfrm_policy_kill(pol);
1174                 return 0;
1175         }
1176         return -ENOENT;
1177 }
1178 EXPORT_SYMBOL(xfrm_policy_delete);
1179
1180 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1181 {
1182         struct net *net = xp_net(pol);
1183         struct xfrm_policy *old_pol;
1184
1185 #ifdef CONFIG_XFRM_SUB_POLICY
1186         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1187                 return -EINVAL;
1188 #endif
1189
1190         write_lock_bh(&xfrm_policy_lock);
1191         old_pol = sk->sk_policy[dir];
1192         sk->sk_policy[dir] = pol;
1193         if (pol) {
1194                 pol->curlft.add_time = get_seconds();
1195                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir);
1196                 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1197         }
1198         if (old_pol) {
1199                 if (pol)
1200                         xfrm_policy_requeue(old_pol, pol);
1201
1202                 /* Unlinking succeeds always. This is the only function
1203                  * allowed to delete or replace socket policy.
1204                  */
1205                 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1206         }
1207         write_unlock_bh(&xfrm_policy_lock);
1208
1209         if (old_pol) {
1210                 xfrm_policy_kill(old_pol);
1211         }
1212         return 0;
1213 }
1214
1215 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1216 {
1217         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1218
1219         if (newp) {
1220                 newp->selector = old->selector;
1221                 if (security_xfrm_policy_clone(old->security,
1222                                                &newp->security)) {
1223                         kfree(newp);
1224                         return NULL;  /* ENOMEM */
1225                 }
1226                 newp->lft = old->lft;
1227                 newp->curlft = old->curlft;
1228                 newp->mark = old->mark;
1229                 newp->action = old->action;
1230                 newp->flags = old->flags;
1231                 newp->xfrm_nr = old->xfrm_nr;
1232                 newp->index = old->index;
1233                 newp->type = old->type;
1234                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1235                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1236                 write_lock_bh(&xfrm_policy_lock);
1237                 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1238                 write_unlock_bh(&xfrm_policy_lock);
1239                 xfrm_pol_put(newp);
1240         }
1241         return newp;
1242 }
1243
1244 int __xfrm_sk_clone_policy(struct sock *sk)
1245 {
1246         struct xfrm_policy *p0 = sk->sk_policy[0],
1247                            *p1 = sk->sk_policy[1];
1248
1249         sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1250         if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1251                 return -ENOMEM;
1252         if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1253                 return -ENOMEM;
1254         return 0;
1255 }
1256
1257 static int
1258 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1259                unsigned short family)
1260 {
1261         int err;
1262         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1263
1264         if (unlikely(afinfo == NULL))
1265                 return -EINVAL;
1266         err = afinfo->get_saddr(net, local, remote);
1267         xfrm_policy_put_afinfo(afinfo);
1268         return err;
1269 }
1270
1271 /* Resolve list of templates for the flow, given policy. */
1272
1273 static int
1274 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1275                       struct xfrm_state **xfrm, unsigned short family)
1276 {
1277         struct net *net = xp_net(policy);
1278         int nx;
1279         int i, error;
1280         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1281         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1282         xfrm_address_t tmp;
1283
1284         for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1285                 struct xfrm_state *x;
1286                 xfrm_address_t *remote = daddr;
1287                 xfrm_address_t *local  = saddr;
1288                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1289
1290                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1291                     tmpl->mode == XFRM_MODE_BEET) {
1292                         remote = &tmpl->id.daddr;
1293                         local = &tmpl->saddr;
1294                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1295                                 error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family);
1296                                 if (error)
1297                                         goto fail;
1298                                 local = &tmp;
1299                         }
1300                 }
1301
1302                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1303
1304                 if (x && x->km.state == XFRM_STATE_VALID) {
1305                         xfrm[nx++] = x;
1306                         daddr = remote;
1307                         saddr = local;
1308                         continue;
1309                 }
1310                 if (x) {
1311                         error = (x->km.state == XFRM_STATE_ERROR ?
1312                                  -EINVAL : -EAGAIN);
1313                         xfrm_state_put(x);
1314                 }
1315                 else if (error == -ESRCH)
1316                         error = -EAGAIN;
1317
1318                 if (!tmpl->optional)
1319                         goto fail;
1320         }
1321         return nx;
1322
1323 fail:
1324         for (nx--; nx>=0; nx--)
1325                 xfrm_state_put(xfrm[nx]);
1326         return error;
1327 }
1328
1329 static int
1330 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1331                   struct xfrm_state **xfrm, unsigned short family)
1332 {
1333         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1334         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1335         int cnx = 0;
1336         int error;
1337         int ret;
1338         int i;
1339
1340         for (i = 0; i < npols; i++) {
1341                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1342                         error = -ENOBUFS;
1343                         goto fail;
1344                 }
1345
1346                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1347                 if (ret < 0) {
1348                         error = ret;
1349                         goto fail;
1350                 } else
1351                         cnx += ret;
1352         }
1353
1354         /* found states are sorted for outbound processing */
1355         if (npols > 1)
1356                 xfrm_state_sort(xfrm, tpp, cnx, family);
1357
1358         return cnx;
1359
1360  fail:
1361         for (cnx--; cnx>=0; cnx--)
1362                 xfrm_state_put(tpp[cnx]);
1363         return error;
1364
1365 }
1366
1367 /* Check that the bundle accepts the flow and its components are
1368  * still valid.
1369  */
1370
1371 static inline int xfrm_get_tos(const struct flowi *fl, int family)
1372 {
1373         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1374         int tos;
1375
1376         if (!afinfo)
1377                 return -EINVAL;
1378
1379         tos = afinfo->get_tos(fl);
1380
1381         xfrm_policy_put_afinfo(afinfo);
1382
1383         return tos;
1384 }
1385
1386 static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1387 {
1388         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1389         struct dst_entry *dst = &xdst->u.dst;
1390
1391         if (xdst->route == NULL) {
1392                 /* Dummy bundle - if it has xfrms we were not
1393                  * able to build bundle as template resolution failed.
1394                  * It means we need to try again resolving. */
1395                 if (xdst->num_xfrms > 0)
1396                         return NULL;
1397         } else if (dst->flags & DST_XFRM_QUEUE) {
1398                 return NULL;
1399         } else {
1400                 /* Real bundle */
1401                 if (stale_bundle(dst))
1402                         return NULL;
1403         }
1404
1405         dst_hold(dst);
1406         return flo;
1407 }
1408
1409 static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1410 {
1411         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1412         struct dst_entry *dst = &xdst->u.dst;
1413
1414         if (!xdst->route)
1415                 return 0;
1416         if (stale_bundle(dst))
1417                 return 0;
1418
1419         return 1;
1420 }
1421
1422 static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1423 {
1424         struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1425         struct dst_entry *dst = &xdst->u.dst;
1426
1427         dst_free(dst);
1428 }
1429
1430 static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1431         .get = xfrm_bundle_flo_get,
1432         .check = xfrm_bundle_flo_check,
1433         .delete = xfrm_bundle_flo_delete,
1434 };
1435
1436 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1437 {
1438         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1439         struct dst_ops *dst_ops;
1440         struct xfrm_dst *xdst;
1441
1442         if (!afinfo)
1443                 return ERR_PTR(-EINVAL);
1444
1445         switch (family) {
1446         case AF_INET:
1447                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1448                 break;
1449 #if IS_ENABLED(CONFIG_IPV6)
1450         case AF_INET6:
1451                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1452                 break;
1453 #endif
1454         default:
1455                 BUG();
1456         }
1457         xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1458
1459         if (likely(xdst)) {
1460                 struct dst_entry *dst = &xdst->u.dst;
1461
1462                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1463                 xdst->flo.ops = &xfrm_bundle_fc_ops;
1464                 if (afinfo->init_dst)
1465                         afinfo->init_dst(net, xdst);
1466         } else
1467                 xdst = ERR_PTR(-ENOBUFS);
1468
1469         xfrm_policy_put_afinfo(afinfo);
1470
1471         return xdst;
1472 }
1473
1474 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1475                                  int nfheader_len)
1476 {
1477         struct xfrm_policy_afinfo *afinfo =
1478                 xfrm_policy_get_afinfo(dst->ops->family);
1479         int err;
1480
1481         if (!afinfo)
1482                 return -EINVAL;
1483
1484         err = afinfo->init_path(path, dst, nfheader_len);
1485
1486         xfrm_policy_put_afinfo(afinfo);
1487
1488         return err;
1489 }
1490
1491 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1492                                 const struct flowi *fl)
1493 {
1494         struct xfrm_policy_afinfo *afinfo =
1495                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1496         int err;
1497
1498         if (!afinfo)
1499                 return -EINVAL;
1500
1501         err = afinfo->fill_dst(xdst, dev, fl);
1502
1503         xfrm_policy_put_afinfo(afinfo);
1504
1505         return err;
1506 }
1507
1508
1509 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1510  * all the metrics... Shortly, bundle a bundle.
1511  */
1512
1513 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1514                                             struct xfrm_state **xfrm, int nx,
1515                                             const struct flowi *fl,
1516                                             struct dst_entry *dst)
1517 {
1518         struct net *net = xp_net(policy);
1519         unsigned long now = jiffies;
1520         struct net_device *dev;
1521         struct xfrm_mode *inner_mode;
1522         struct dst_entry *dst_prev = NULL;
1523         struct dst_entry *dst0 = NULL;
1524         int i = 0;
1525         int err;
1526         int header_len = 0;
1527         int nfheader_len = 0;
1528         int trailer_len = 0;
1529         int tos;
1530         int family = policy->selector.family;
1531         xfrm_address_t saddr, daddr;
1532
1533         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1534
1535         tos = xfrm_get_tos(fl, family);
1536         err = tos;
1537         if (tos < 0)
1538                 goto put_states;
1539
1540         dst_hold(dst);
1541
1542         for (; i < nx; i++) {
1543                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1544                 struct dst_entry *dst1 = &xdst->u.dst;
1545
1546                 err = PTR_ERR(xdst);
1547                 if (IS_ERR(xdst)) {
1548                         dst_release(dst);
1549                         goto put_states;
1550                 }
1551
1552                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1553                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1554                                                         xfrm_af2proto(family));
1555                         if (!inner_mode) {
1556                                 err = -EAFNOSUPPORT;
1557                                 dst_release(dst);
1558                                 goto put_states;
1559                         }
1560                 } else
1561                         inner_mode = xfrm[i]->inner_mode;
1562
1563                 if (!dst_prev)
1564                         dst0 = dst1;
1565                 else {
1566                         dst_prev->child = dst_clone(dst1);
1567                         dst1->flags |= DST_NOHASH;
1568                 }
1569
1570                 xdst->route = dst;
1571                 dst_copy_metrics(dst1, dst);
1572
1573                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1574                         family = xfrm[i]->props.family;
1575                         dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1576                                               family);
1577                         err = PTR_ERR(dst);
1578                         if (IS_ERR(dst))
1579                                 goto put_states;
1580                 } else
1581                         dst_hold(dst);
1582
1583                 dst1->xfrm = xfrm[i];
1584                 xdst->xfrm_genid = xfrm[i]->genid;
1585
1586                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1587                 dst1->flags |= DST_HOST;
1588                 dst1->lastuse = now;
1589
1590                 dst1->input = dst_discard;
1591                 dst1->output = inner_mode->afinfo->output;
1592
1593                 dst1->next = dst_prev;
1594                 dst_prev = dst1;
1595
1596                 header_len += xfrm[i]->props.header_len;
1597                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1598                         nfheader_len += xfrm[i]->props.header_len;
1599                 trailer_len += xfrm[i]->props.trailer_len;
1600         }
1601
1602         dst_prev->child = dst;
1603         dst0->path = dst;
1604
1605         err = -ENODEV;
1606         dev = dst->dev;
1607         if (!dev)
1608                 goto free_dst;
1609
1610         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1611         xfrm_init_pmtu(dst_prev);
1612
1613         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1614                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1615
1616                 err = xfrm_fill_dst(xdst, dev, fl);
1617                 if (err)
1618                         goto free_dst;
1619
1620                 dst_prev->header_len = header_len;
1621                 dst_prev->trailer_len = trailer_len;
1622                 header_len -= xdst->u.dst.xfrm->props.header_len;
1623                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1624         }
1625
1626 out:
1627         return dst0;
1628
1629 put_states:
1630         for (; i < nx; i++)
1631                 xfrm_state_put(xfrm[i]);
1632 free_dst:
1633         if (dst0)
1634                 dst_free(dst0);
1635         dst0 = ERR_PTR(err);
1636         goto out;
1637 }
1638
1639 static int inline
1640 xfrm_dst_alloc_copy(void **target, const void *src, int size)
1641 {
1642         if (!*target) {
1643                 *target = kmalloc(size, GFP_ATOMIC);
1644                 if (!*target)
1645                         return -ENOMEM;
1646         }
1647         memcpy(*target, src, size);
1648         return 0;
1649 }
1650
1651 static int inline
1652 xfrm_dst_update_parent(struct dst_entry *dst, const struct xfrm_selector *sel)
1653 {
1654 #ifdef CONFIG_XFRM_SUB_POLICY
1655         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1656         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1657                                    sel, sizeof(*sel));
1658 #else
1659         return 0;
1660 #endif
1661 }
1662
1663 static int inline
1664 xfrm_dst_update_origin(struct dst_entry *dst, const struct flowi *fl)
1665 {
1666 #ifdef CONFIG_XFRM_SUB_POLICY
1667         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1668         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1669 #else
1670         return 0;
1671 #endif
1672 }
1673
1674 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1675                                 struct xfrm_policy **pols,
1676                                 int *num_pols, int *num_xfrms)
1677 {
1678         int i;
1679
1680         if (*num_pols == 0 || !pols[0]) {
1681                 *num_pols = 0;
1682                 *num_xfrms = 0;
1683                 return 0;
1684         }
1685         if (IS_ERR(pols[0]))
1686                 return PTR_ERR(pols[0]);
1687
1688         *num_xfrms = pols[0]->xfrm_nr;
1689
1690 #ifdef CONFIG_XFRM_SUB_POLICY
1691         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1692             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1693                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1694                                                     XFRM_POLICY_TYPE_MAIN,
1695                                                     fl, family,
1696                                                     XFRM_POLICY_OUT);
1697                 if (pols[1]) {
1698                         if (IS_ERR(pols[1])) {
1699                                 xfrm_pols_put(pols, *num_pols);
1700                                 return PTR_ERR(pols[1]);
1701                         }
1702                         (*num_pols) ++;
1703                         (*num_xfrms) += pols[1]->xfrm_nr;
1704                 }
1705         }
1706 #endif
1707         for (i = 0; i < *num_pols; i++) {
1708                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1709                         *num_xfrms = -1;
1710                         break;
1711                 }
1712         }
1713
1714         return 0;
1715
1716 }
1717
1718 static struct xfrm_dst *
1719 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1720                                const struct flowi *fl, u16 family,
1721                                struct dst_entry *dst_orig)
1722 {
1723         struct net *net = xp_net(pols[0]);
1724         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1725         struct dst_entry *dst;
1726         struct xfrm_dst *xdst;
1727         int err;
1728
1729         /* Try to instantiate a bundle */
1730         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1731         if (err <= 0) {
1732                 if (err != 0 && err != -EAGAIN)
1733                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1734                 return ERR_PTR(err);
1735         }
1736
1737         dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1738         if (IS_ERR(dst)) {
1739                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1740                 return ERR_CAST(dst);
1741         }
1742
1743         xdst = (struct xfrm_dst *)dst;
1744         xdst->num_xfrms = err;
1745         if (num_pols > 1)
1746                 err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1747         else
1748                 err = xfrm_dst_update_origin(dst, fl);
1749         if (unlikely(err)) {
1750                 dst_free(dst);
1751                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1752                 return ERR_PTR(err);
1753         }
1754
1755         xdst->num_pols = num_pols;
1756         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1757         xdst->policy_genid = atomic_read(&pols[0]->genid);
1758
1759         return xdst;
1760 }
1761
1762 static void xfrm_policy_queue_process(unsigned long arg)
1763 {
1764         int err = 0;
1765         struct sk_buff *skb;
1766         struct sock *sk;
1767         struct dst_entry *dst;
1768         struct xfrm_policy *pol = (struct xfrm_policy *)arg;
1769         struct xfrm_policy_queue *pq = &pol->polq;
1770         struct flowi fl;
1771         struct sk_buff_head list;
1772
1773         spin_lock(&pq->hold_queue.lock);
1774         skb = skb_peek(&pq->hold_queue);
1775         if (!skb) {
1776                 spin_unlock(&pq->hold_queue.lock);
1777                 goto out;
1778         }
1779         dst = skb_dst(skb);
1780         sk = skb->sk;
1781         xfrm_decode_session(skb, &fl, dst->ops->family);
1782         spin_unlock(&pq->hold_queue.lock);
1783
1784         dst_hold(dst->path);
1785         dst = xfrm_lookup(xp_net(pol), dst->path, &fl,
1786                           sk, 0);
1787         if (IS_ERR(dst))
1788                 goto purge_queue;
1789
1790         if (dst->flags & DST_XFRM_QUEUE) {
1791                 dst_release(dst);
1792
1793                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1794                         goto purge_queue;
1795
1796                 pq->timeout = pq->timeout << 1;
1797                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1798                         xfrm_pol_hold(pol);
1799         goto out;
1800         }
1801
1802         dst_release(dst);
1803
1804         __skb_queue_head_init(&list);
1805
1806         spin_lock(&pq->hold_queue.lock);
1807         pq->timeout = 0;
1808         skb_queue_splice_init(&pq->hold_queue, &list);
1809         spin_unlock(&pq->hold_queue.lock);
1810
1811         while (!skb_queue_empty(&list)) {
1812                 skb = __skb_dequeue(&list);
1813
1814                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1815                 dst_hold(skb_dst(skb)->path);
1816                 dst = xfrm_lookup(xp_net(pol), skb_dst(skb)->path,
1817                                   &fl, skb->sk, 0);
1818                 if (IS_ERR(dst)) {
1819                         kfree_skb(skb);
1820                         continue;
1821                 }
1822
1823                 nf_reset(skb);
1824                 skb_dst_drop(skb);
1825                 skb_dst_set(skb, dst);
1826
1827                 err = dst_output(skb);
1828         }
1829
1830 out:
1831         xfrm_pol_put(pol);
1832         return;
1833
1834 purge_queue:
1835         pq->timeout = 0;
1836         xfrm_queue_purge(&pq->hold_queue);
1837         xfrm_pol_put(pol);
1838 }
1839
1840 static int xdst_queue_output(struct sk_buff *skb)
1841 {
1842         unsigned long sched_next;
1843         struct dst_entry *dst = skb_dst(skb);
1844         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1845         struct xfrm_policy *pol = xdst->pols[0];
1846         struct xfrm_policy_queue *pq = &pol->polq;
1847
1848         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1849                 kfree_skb(skb);
1850                 return -EAGAIN;
1851         }
1852
1853         skb_dst_force(skb);
1854
1855         spin_lock_bh(&pq->hold_queue.lock);
1856
1857         if (!pq->timeout)
1858                 pq->timeout = XFRM_QUEUE_TMO_MIN;
1859
1860         sched_next = jiffies + pq->timeout;
1861
1862         if (del_timer(&pq->hold_timer)) {
1863                 if (time_before(pq->hold_timer.expires, sched_next))
1864                         sched_next = pq->hold_timer.expires;
1865                 xfrm_pol_put(pol);
1866         }
1867
1868         __skb_queue_tail(&pq->hold_queue, skb);
1869         if (!mod_timer(&pq->hold_timer, sched_next))
1870                 xfrm_pol_hold(pol);
1871
1872         spin_unlock_bh(&pq->hold_queue.lock);
1873
1874         return 0;
1875 }
1876
1877 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1878                                                  struct dst_entry *dst,
1879                                                  const struct flowi *fl,
1880                                                  int num_xfrms,
1881                                                  u16 family)
1882 {
1883         int err;
1884         struct net_device *dev;
1885         struct dst_entry *dst1;
1886         struct xfrm_dst *xdst;
1887
1888         xdst = xfrm_alloc_dst(net, family);
1889         if (IS_ERR(xdst))
1890                 return xdst;
1891
1892         if (net->xfrm.sysctl_larval_drop || num_xfrms <= 0 ||
1893             (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP))
1894                 return xdst;
1895
1896         dst1 = &xdst->u.dst;
1897         dst_hold(dst);
1898         xdst->route = dst;
1899
1900         dst_copy_metrics(dst1, dst);
1901
1902         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1903         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
1904         dst1->lastuse = jiffies;
1905
1906         dst1->input = dst_discard;
1907         dst1->output = xdst_queue_output;
1908
1909         dst_hold(dst);
1910         dst1->child = dst;
1911         dst1->path = dst;
1912
1913         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
1914
1915         err = -ENODEV;
1916         dev = dst->dev;
1917         if (!dev)
1918                 goto free_dst;
1919
1920         err = xfrm_fill_dst(xdst, dev, fl);
1921         if (err)
1922                 goto free_dst;
1923
1924 out:
1925         return xdst;
1926
1927 free_dst:
1928         dst_release(dst1);
1929         xdst = ERR_PTR(err);
1930         goto out;
1931 }
1932
1933 static struct flow_cache_object *
1934 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
1935                    struct flow_cache_object *oldflo, void *ctx)
1936 {
1937         struct dst_entry *dst_orig = (struct dst_entry *)ctx;
1938         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1939         struct xfrm_dst *xdst, *new_xdst;
1940         int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
1941
1942         /* Check if the policies from old bundle are usable */
1943         xdst = NULL;
1944         if (oldflo) {
1945                 xdst = container_of(oldflo, struct xfrm_dst, flo);
1946                 num_pols = xdst->num_pols;
1947                 num_xfrms = xdst->num_xfrms;
1948                 pol_dead = 0;
1949                 for (i = 0; i < num_pols; i++) {
1950                         pols[i] = xdst->pols[i];
1951                         pol_dead |= pols[i]->walk.dead;
1952                 }
1953                 if (pol_dead) {
1954                         dst_free(&xdst->u.dst);
1955                         xdst = NULL;
1956                         num_pols = 0;
1957                         num_xfrms = 0;
1958                         oldflo = NULL;
1959                 }
1960         }
1961
1962         /* Resolve policies to use if we couldn't get them from
1963          * previous cache entry */
1964         if (xdst == NULL) {
1965                 num_pols = 1;
1966                 pols[0] = __xfrm_policy_lookup(net, fl, family,
1967                                                flow_to_policy_dir(dir));
1968                 err = xfrm_expand_policies(fl, family, pols,
1969                                            &num_pols, &num_xfrms);
1970                 if (err < 0)
1971                         goto inc_error;
1972                 if (num_pols == 0)
1973                         return NULL;
1974                 if (num_xfrms <= 0)
1975                         goto make_dummy_bundle;
1976         }
1977
1978         new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, dst_orig);
1979         if (IS_ERR(new_xdst)) {
1980                 err = PTR_ERR(new_xdst);
1981                 if (err != -EAGAIN)
1982                         goto error;
1983                 if (oldflo == NULL)
1984                         goto make_dummy_bundle;
1985                 dst_hold(&xdst->u.dst);
1986                 return oldflo;
1987         } else if (new_xdst == NULL) {
1988                 num_xfrms = 0;
1989                 if (oldflo == NULL)
1990                         goto make_dummy_bundle;
1991                 xdst->num_xfrms = 0;
1992                 dst_hold(&xdst->u.dst);
1993                 return oldflo;
1994         }
1995
1996         /* Kill the previous bundle */
1997         if (xdst) {
1998                 /* The policies were stolen for newly generated bundle */
1999                 xdst->num_pols = 0;
2000                 dst_free(&xdst->u.dst);
2001         }
2002
2003         /* Flow cache does not have reference, it dst_free()'s,
2004          * but we do need to return one reference for original caller */
2005         dst_hold(&new_xdst->u.dst);
2006         return &new_xdst->flo;
2007
2008 make_dummy_bundle:
2009         /* We found policies, but there's no bundles to instantiate:
2010          * either because the policy blocks, has no transformations or
2011          * we could not build template (no xfrm_states).*/
2012         xdst = xfrm_create_dummy_bundle(net, dst_orig, fl, num_xfrms, family);
2013         if (IS_ERR(xdst)) {
2014                 xfrm_pols_put(pols, num_pols);
2015                 return ERR_CAST(xdst);
2016         }
2017         xdst->num_pols = num_pols;
2018         xdst->num_xfrms = num_xfrms;
2019         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
2020
2021         dst_hold(&xdst->u.dst);
2022         return &xdst->flo;
2023
2024 inc_error:
2025         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2026 error:
2027         if (xdst != NULL)
2028                 dst_free(&xdst->u.dst);
2029         else
2030                 xfrm_pols_put(pols, num_pols);
2031         return ERR_PTR(err);
2032 }
2033
2034 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2035                                         struct dst_entry *dst_orig)
2036 {
2037         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2038         struct dst_entry *ret;
2039
2040         if (!afinfo) {
2041                 dst_release(dst_orig);
2042                 return ERR_PTR(-EINVAL);
2043         } else {
2044                 ret = afinfo->blackhole_route(net, dst_orig);
2045         }
2046         xfrm_policy_put_afinfo(afinfo);
2047
2048         return ret;
2049 }
2050
2051 /* Main function: finds/creates a bundle for given flow.
2052  *
2053  * At the moment we eat a raw IP route. Mostly to speed up lookups
2054  * on interfaces with disabled IPsec.
2055  */
2056 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2057                               const struct flowi *fl,
2058                               struct sock *sk, int flags)
2059 {
2060         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2061         struct flow_cache_object *flo;
2062         struct xfrm_dst *xdst;
2063         struct dst_entry *dst, *route;
2064         u16 family = dst_orig->ops->family;
2065         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
2066         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2067
2068 restart:
2069         dst = NULL;
2070         xdst = NULL;
2071         route = NULL;
2072
2073         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2074                 num_pols = 1;
2075                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
2076                 err = xfrm_expand_policies(fl, family, pols,
2077                                            &num_pols, &num_xfrms);
2078                 if (err < 0)
2079                         goto dropdst;
2080
2081                 if (num_pols) {
2082                         if (num_xfrms <= 0) {
2083                                 drop_pols = num_pols;
2084                                 goto no_transform;
2085                         }
2086
2087                         xdst = xfrm_resolve_and_create_bundle(
2088                                         pols, num_pols, fl,
2089                                         family, dst_orig);
2090                         if (IS_ERR(xdst)) {
2091                                 xfrm_pols_put(pols, num_pols);
2092                                 err = PTR_ERR(xdst);
2093                                 goto dropdst;
2094                         } else if (xdst == NULL) {
2095                                 num_xfrms = 0;
2096                                 drop_pols = num_pols;
2097                                 goto no_transform;
2098                         }
2099
2100                         dst_hold(&xdst->u.dst);
2101
2102                         spin_lock_bh(&xfrm_policy_sk_bundle_lock);
2103                         xdst->u.dst.next = xfrm_policy_sk_bundles;
2104                         xfrm_policy_sk_bundles = &xdst->u.dst;
2105                         spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
2106
2107                         route = xdst->route;
2108                 }
2109         }
2110
2111         if (xdst == NULL) {
2112                 /* To accelerate a bit...  */
2113                 if ((dst_orig->flags & DST_NOXFRM) ||
2114                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2115                         goto nopol;
2116
2117                 flo = flow_cache_lookup(net, fl, family, dir,
2118                                         xfrm_bundle_lookup, dst_orig);
2119                 if (flo == NULL)
2120                         goto nopol;
2121                 if (IS_ERR(flo)) {
2122                         err = PTR_ERR(flo);
2123                         goto dropdst;
2124                 }
2125                 xdst = container_of(flo, struct xfrm_dst, flo);
2126
2127                 num_pols = xdst->num_pols;
2128                 num_xfrms = xdst->num_xfrms;
2129                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy*) * num_pols);
2130                 route = xdst->route;
2131         }
2132
2133         dst = &xdst->u.dst;
2134         if (route == NULL && num_xfrms > 0) {
2135                 /* The only case when xfrm_bundle_lookup() returns a
2136                  * bundle with null route, is when the template could
2137                  * not be resolved. It means policies are there, but
2138                  * bundle could not be created, since we don't yet
2139                  * have the xfrm_state's. We need to wait for KM to
2140                  * negotiate new SA's or bail out with error.*/
2141                 if (net->xfrm.sysctl_larval_drop) {
2142                         dst_release(dst);
2143                         xfrm_pols_put(pols, drop_pols);
2144                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2145
2146                         return make_blackhole(net, family, dst_orig);
2147                 }
2148                 if (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP) {
2149                         DECLARE_WAITQUEUE(wait, current);
2150
2151                         add_wait_queue(&net->xfrm.km_waitq, &wait);
2152                         set_current_state(TASK_INTERRUPTIBLE);
2153                         schedule();
2154                         set_current_state(TASK_RUNNING);
2155                         remove_wait_queue(&net->xfrm.km_waitq, &wait);
2156
2157                         if (!signal_pending(current)) {
2158                                 dst_release(dst);
2159                                 goto restart;
2160                         }
2161
2162                         err = -ERESTART;
2163                 } else
2164                         err = -EAGAIN;
2165
2166                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2167                 goto error;
2168         }
2169
2170 no_transform:
2171         if (num_pols == 0)
2172                 goto nopol;
2173
2174         if ((flags & XFRM_LOOKUP_ICMP) &&
2175             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2176                 err = -ENOENT;
2177                 goto error;
2178         }
2179
2180         for (i = 0; i < num_pols; i++)
2181                 pols[i]->curlft.use_time = get_seconds();
2182
2183         if (num_xfrms < 0) {
2184                 /* Prohibit the flow */
2185                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2186                 err = -EPERM;
2187                 goto error;
2188         } else if (num_xfrms > 0) {
2189                 /* Flow transformed */
2190                 dst_release(dst_orig);
2191         } else {
2192                 /* Flow passes untransformed */
2193                 dst_release(dst);
2194                 dst = dst_orig;
2195         }
2196 ok:
2197         xfrm_pols_put(pols, drop_pols);
2198         if (dst && dst->xfrm &&
2199             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2200                 dst->flags |= DST_XFRM_TUNNEL;
2201         return dst;
2202
2203 nopol:
2204         if (!(flags & XFRM_LOOKUP_ICMP)) {
2205                 dst = dst_orig;
2206                 goto ok;
2207         }
2208         err = -ENOENT;
2209 error:
2210         dst_release(dst);
2211 dropdst:
2212         dst_release(dst_orig);
2213         xfrm_pols_put(pols, drop_pols);
2214         return ERR_PTR(err);
2215 }
2216 EXPORT_SYMBOL(xfrm_lookup);
2217
2218 static inline int
2219 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2220 {
2221         struct xfrm_state *x;
2222
2223         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2224                 return 0;
2225         x = skb->sp->xvec[idx];
2226         if (!x->type->reject)
2227                 return 0;
2228         return x->type->reject(x, skb, fl);
2229 }
2230
2231 /* When skb is transformed back to its "native" form, we have to
2232  * check policy restrictions. At the moment we make this in maximally
2233  * stupid way. Shame on me. :-) Of course, connected sockets must
2234  * have policy cached at them.
2235  */
2236
2237 static inline int
2238 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2239               unsigned short family)
2240 {
2241         if (xfrm_state_kern(x))
2242                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2243         return  x->id.proto == tmpl->id.proto &&
2244                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2245                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2246                 x->props.mode == tmpl->mode &&
2247                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2248                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2249                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2250                   xfrm_state_addr_cmp(tmpl, x, family));
2251 }
2252
2253 /*
2254  * 0 or more than 0 is returned when validation is succeeded (either bypass
2255  * because of optional transport mode, or next index of the mathced secpath
2256  * state with the template.
2257  * -1 is returned when no matching template is found.
2258  * Otherwise "-2 - errored_index" is returned.
2259  */
2260 static inline int
2261 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2262                unsigned short family)
2263 {
2264         int idx = start;
2265
2266         if (tmpl->optional) {
2267                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2268                         return start;
2269         } else
2270                 start = -1;
2271         for (; idx < sp->len; idx++) {
2272                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2273                         return ++idx;
2274                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2275                         if (start == -1)
2276                                 start = -2-idx;
2277                         break;
2278                 }
2279         }
2280         return start;
2281 }
2282
2283 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2284                           unsigned int family, int reverse)
2285 {
2286         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2287         int err;
2288
2289         if (unlikely(afinfo == NULL))
2290                 return -EAFNOSUPPORT;
2291
2292         afinfo->decode_session(skb, fl, reverse);
2293         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2294         xfrm_policy_put_afinfo(afinfo);
2295         return err;
2296 }
2297 EXPORT_SYMBOL(__xfrm_decode_session);
2298
2299 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2300 {
2301         for (; k < sp->len; k++) {
2302                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2303                         *idxp = k;
2304                         return 1;
2305                 }
2306         }
2307
2308         return 0;
2309 }
2310
2311 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2312                         unsigned short family)
2313 {
2314         struct net *net = dev_net(skb->dev);
2315         struct xfrm_policy *pol;
2316         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2317         int npols = 0;
2318         int xfrm_nr;
2319         int pi;
2320         int reverse;
2321         struct flowi fl;
2322         u8 fl_dir;
2323         int xerr_idx = -1;
2324
2325         reverse = dir & ~XFRM_POLICY_MASK;
2326         dir &= XFRM_POLICY_MASK;
2327         fl_dir = policy_to_flow_dir(dir);
2328
2329         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2330                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2331                 return 0;
2332         }
2333
2334         nf_nat_decode_session(skb, &fl, family);
2335
2336         /* First, check used SA against their selectors. */
2337         if (skb->sp) {
2338                 int i;
2339
2340                 for (i=skb->sp->len-1; i>=0; i--) {
2341                         struct xfrm_state *x = skb->sp->xvec[i];
2342                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2343                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2344                                 return 0;
2345                         }
2346                 }
2347         }
2348
2349         pol = NULL;
2350         if (sk && sk->sk_policy[dir]) {
2351                 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2352                 if (IS_ERR(pol)) {
2353                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2354                         return 0;
2355                 }
2356         }
2357
2358         if (!pol) {
2359                 struct flow_cache_object *flo;
2360
2361                 flo = flow_cache_lookup(net, &fl, family, fl_dir,
2362                                         xfrm_policy_lookup, NULL);
2363                 if (IS_ERR_OR_NULL(flo))
2364                         pol = ERR_CAST(flo);
2365                 else
2366                         pol = container_of(flo, struct xfrm_policy, flo);
2367         }
2368
2369         if (IS_ERR(pol)) {
2370                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2371                 return 0;
2372         }
2373
2374         if (!pol) {
2375                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2376                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2377                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2378                         return 0;
2379                 }
2380                 return 1;
2381         }
2382
2383         pol->curlft.use_time = get_seconds();
2384
2385         pols[0] = pol;
2386         npols ++;
2387 #ifdef CONFIG_XFRM_SUB_POLICY
2388         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2389                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2390                                                     &fl, family,
2391                                                     XFRM_POLICY_IN);
2392                 if (pols[1]) {
2393                         if (IS_ERR(pols[1])) {
2394                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2395                                 return 0;
2396                         }
2397                         pols[1]->curlft.use_time = get_seconds();
2398                         npols ++;
2399                 }
2400         }
2401 #endif
2402
2403         if (pol->action == XFRM_POLICY_ALLOW) {
2404                 struct sec_path *sp;
2405                 static struct sec_path dummy;
2406                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2407                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2408                 struct xfrm_tmpl **tpp = tp;
2409                 int ti = 0;
2410                 int i, k;
2411
2412                 if ((sp = skb->sp) == NULL)
2413                         sp = &dummy;
2414
2415                 for (pi = 0; pi < npols; pi++) {
2416                         if (pols[pi] != pol &&
2417                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2418                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2419                                 goto reject;
2420                         }
2421                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2422                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2423                                 goto reject_error;
2424                         }
2425                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2426                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2427                 }
2428                 xfrm_nr = ti;
2429                 if (npols > 1) {
2430                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
2431                         tpp = stp;
2432                 }
2433
2434                 /* For each tunnel xfrm, find the first matching tmpl.
2435                  * For each tmpl before that, find corresponding xfrm.
2436                  * Order is _important_. Later we will implement
2437                  * some barriers, but at the moment barriers
2438                  * are implied between each two transformations.
2439                  */
2440                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2441                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2442                         if (k < 0) {
2443                                 if (k < -1)
2444                                         /* "-2 - errored_index" returned */
2445                                         xerr_idx = -(2+k);
2446                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2447                                 goto reject;
2448                         }
2449                 }
2450
2451                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2452                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2453                         goto reject;
2454                 }
2455
2456                 xfrm_pols_put(pols, npols);
2457                 return 1;
2458         }
2459         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2460
2461 reject:
2462         xfrm_secpath_reject(xerr_idx, skb, &fl);
2463 reject_error:
2464         xfrm_pols_put(pols, npols);
2465         return 0;
2466 }
2467 EXPORT_SYMBOL(__xfrm_policy_check);
2468
2469 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2470 {
2471         struct net *net = dev_net(skb->dev);
2472         struct flowi fl;
2473         struct dst_entry *dst;
2474         int res = 1;
2475
2476         if (xfrm_decode_session(skb, &fl, family) < 0) {
2477                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2478                 return 0;
2479         }
2480
2481         skb_dst_force(skb);
2482
2483         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, 0);
2484         if (IS_ERR(dst)) {
2485                 res = 0;
2486                 dst = NULL;
2487         }
2488         skb_dst_set(skb, dst);
2489         return res;
2490 }
2491 EXPORT_SYMBOL(__xfrm_route_forward);
2492
2493 /* Optimize later using cookies and generation ids. */
2494
2495 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2496 {
2497         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2498          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2499          * get validated by dst_ops->check on every use.  We do this
2500          * because when a normal route referenced by an XFRM dst is
2501          * obsoleted we do not go looking around for all parent
2502          * referencing XFRM dsts so that we can invalidate them.  It
2503          * is just too much work.  Instead we make the checks here on
2504          * every use.  For example:
2505          *
2506          *      XFRM dst A --> IPv4 dst X
2507          *
2508          * X is the "xdst->route" of A (X is also the "dst->path" of A
2509          * in this example).  If X is marked obsolete, "A" will not
2510          * notice.  That's what we are validating here via the
2511          * stale_bundle() check.
2512          *
2513          * When a policy's bundle is pruned, we dst_free() the XFRM
2514          * dst which causes it's ->obsolete field to be set to
2515          * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2516          * this, we want to force a new route lookup.
2517          */
2518         if (dst->obsolete < 0 && !stale_bundle(dst))
2519                 return dst;
2520
2521         return NULL;
2522 }
2523
2524 static int stale_bundle(struct dst_entry *dst)
2525 {
2526         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2527 }
2528
2529 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2530 {
2531         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2532                 dst->dev = dev_net(dev)->loopback_dev;
2533                 dev_hold(dst->dev);
2534                 dev_put(dev);
2535         }
2536 }
2537 EXPORT_SYMBOL(xfrm_dst_ifdown);
2538
2539 static void xfrm_link_failure(struct sk_buff *skb)
2540 {
2541         /* Impossible. Such dst must be popped before reaches point of failure. */
2542 }
2543
2544 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2545 {
2546         if (dst) {
2547                 if (dst->obsolete) {
2548                         dst_release(dst);
2549                         dst = NULL;
2550                 }
2551         }
2552         return dst;
2553 }
2554
2555 static void __xfrm_garbage_collect(struct net *net)
2556 {
2557         struct dst_entry *head, *next;
2558
2559         spin_lock_bh(&xfrm_policy_sk_bundle_lock);
2560         head = xfrm_policy_sk_bundles;
2561         xfrm_policy_sk_bundles = NULL;
2562         spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
2563
2564         while (head) {
2565                 next = head->next;
2566                 dst_free(head);
2567                 head = next;
2568         }
2569 }
2570
2571 void xfrm_garbage_collect(struct net *net)
2572 {
2573         flow_cache_flush();
2574         __xfrm_garbage_collect(net);
2575 }
2576 EXPORT_SYMBOL(xfrm_garbage_collect);
2577
2578 static void xfrm_garbage_collect_deferred(struct net *net)
2579 {
2580         flow_cache_flush_deferred();
2581         __xfrm_garbage_collect(net);
2582 }
2583
2584 static void xfrm_init_pmtu(struct dst_entry *dst)
2585 {
2586         do {
2587                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2588                 u32 pmtu, route_mtu_cached;
2589
2590                 pmtu = dst_mtu(dst->child);
2591                 xdst->child_mtu_cached = pmtu;
2592
2593                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2594
2595                 route_mtu_cached = dst_mtu(xdst->route);
2596                 xdst->route_mtu_cached = route_mtu_cached;
2597
2598                 if (pmtu > route_mtu_cached)
2599                         pmtu = route_mtu_cached;
2600
2601                 dst_metric_set(dst, RTAX_MTU, pmtu);
2602         } while ((dst = dst->next));
2603 }
2604
2605 /* Check that the bundle accepts the flow and its components are
2606  * still valid.
2607  */
2608
2609 static int xfrm_bundle_ok(struct xfrm_dst *first)
2610 {
2611         struct dst_entry *dst = &first->u.dst;
2612         struct xfrm_dst *last;
2613         u32 mtu;
2614
2615         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2616             (dst->dev && !netif_running(dst->dev)))
2617                 return 0;
2618
2619         if (dst->flags & DST_XFRM_QUEUE)
2620                 return 1;
2621
2622         last = NULL;
2623
2624         do {
2625                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2626
2627                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2628                         return 0;
2629                 if (xdst->xfrm_genid != dst->xfrm->genid)
2630                         return 0;
2631                 if (xdst->num_pols > 0 &&
2632                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2633                         return 0;
2634
2635                 mtu = dst_mtu(dst->child);
2636                 if (xdst->child_mtu_cached != mtu) {
2637                         last = xdst;
2638                         xdst->child_mtu_cached = mtu;
2639                 }
2640
2641                 if (!dst_check(xdst->route, xdst->route_cookie))
2642                         return 0;
2643                 mtu = dst_mtu(xdst->route);
2644                 if (xdst->route_mtu_cached != mtu) {
2645                         last = xdst;
2646                         xdst->route_mtu_cached = mtu;
2647                 }
2648
2649                 dst = dst->child;
2650         } while (dst->xfrm);
2651
2652         if (likely(!last))
2653                 return 1;
2654
2655         mtu = last->child_mtu_cached;
2656         for (;;) {
2657                 dst = &last->u.dst;
2658
2659                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2660                 if (mtu > last->route_mtu_cached)
2661                         mtu = last->route_mtu_cached;
2662                 dst_metric_set(dst, RTAX_MTU, mtu);
2663
2664                 if (last == first)
2665                         break;
2666
2667                 last = (struct xfrm_dst *)last->u.dst.next;
2668                 last->child_mtu_cached = mtu;
2669         }
2670
2671         return 1;
2672 }
2673
2674 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2675 {
2676         return dst_metric_advmss(dst->path);
2677 }
2678
2679 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2680 {
2681         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2682
2683         return mtu ? : dst_mtu(dst->path);
2684 }
2685
2686 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2687                                            struct sk_buff *skb,
2688                                            const void *daddr)
2689 {
2690         return dst->path->ops->neigh_lookup(dst, skb, daddr);
2691 }
2692
2693 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2694 {
2695         struct net *net;
2696         int err = 0;
2697         if (unlikely(afinfo == NULL))
2698                 return -EINVAL;
2699         if (unlikely(afinfo->family >= NPROTO))
2700                 return -EAFNOSUPPORT;
2701         spin_lock(&xfrm_policy_afinfo_lock);
2702         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2703                 err = -ENOBUFS;
2704         else {
2705                 struct dst_ops *dst_ops = afinfo->dst_ops;
2706                 if (likely(dst_ops->kmem_cachep == NULL))
2707                         dst_ops->kmem_cachep = xfrm_dst_cache;
2708                 if (likely(dst_ops->check == NULL))
2709                         dst_ops->check = xfrm_dst_check;
2710                 if (likely(dst_ops->default_advmss == NULL))
2711                         dst_ops->default_advmss = xfrm_default_advmss;
2712                 if (likely(dst_ops->mtu == NULL))
2713                         dst_ops->mtu = xfrm_mtu;
2714                 if (likely(dst_ops->negative_advice == NULL))
2715                         dst_ops->negative_advice = xfrm_negative_advice;
2716                 if (likely(dst_ops->link_failure == NULL))
2717                         dst_ops->link_failure = xfrm_link_failure;
2718                 if (likely(dst_ops->neigh_lookup == NULL))
2719                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2720                 if (likely(afinfo->garbage_collect == NULL))
2721                         afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2722                 rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
2723         }
2724         spin_unlock(&xfrm_policy_afinfo_lock);
2725
2726         rtnl_lock();
2727         for_each_net(net) {
2728                 struct dst_ops *xfrm_dst_ops;
2729
2730                 switch (afinfo->family) {
2731                 case AF_INET:
2732                         xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2733                         break;
2734 #if IS_ENABLED(CONFIG_IPV6)
2735                 case AF_INET6:
2736                         xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2737                         break;
2738 #endif
2739                 default:
2740                         BUG();
2741                 }
2742                 *xfrm_dst_ops = *afinfo->dst_ops;
2743         }
2744         rtnl_unlock();
2745
2746         return err;
2747 }
2748 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2749
2750 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2751 {
2752         int err = 0;
2753         if (unlikely(afinfo == NULL))
2754                 return -EINVAL;
2755         if (unlikely(afinfo->family >= NPROTO))
2756                 return -EAFNOSUPPORT;
2757         spin_lock(&xfrm_policy_afinfo_lock);
2758         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2759                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2760                         err = -EINVAL;
2761                 else
2762                         RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
2763                                          NULL);
2764         }
2765         spin_unlock(&xfrm_policy_afinfo_lock);
2766         if (!err) {
2767                 struct dst_ops *dst_ops = afinfo->dst_ops;
2768
2769                 synchronize_rcu();
2770
2771                 dst_ops->kmem_cachep = NULL;
2772                 dst_ops->check = NULL;
2773                 dst_ops->negative_advice = NULL;
2774                 dst_ops->link_failure = NULL;
2775                 afinfo->garbage_collect = NULL;
2776         }
2777         return err;
2778 }
2779 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2780
2781 static void __net_init xfrm_dst_ops_init(struct net *net)
2782 {
2783         struct xfrm_policy_afinfo *afinfo;
2784
2785         rcu_read_lock();
2786         afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]);
2787         if (afinfo)
2788                 net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2789 #if IS_ENABLED(CONFIG_IPV6)
2790         afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]);
2791         if (afinfo)
2792                 net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2793 #endif
2794         rcu_read_unlock();
2795 }
2796
2797 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2798 {
2799         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2800
2801         switch (event) {
2802         case NETDEV_DOWN:
2803                 xfrm_garbage_collect(dev_net(dev));
2804         }
2805         return NOTIFY_DONE;
2806 }
2807
2808 static struct notifier_block xfrm_dev_notifier = {
2809         .notifier_call  = xfrm_dev_event,
2810 };
2811
2812 #ifdef CONFIG_XFRM_STATISTICS
2813 static int __net_init xfrm_statistics_init(struct net *net)
2814 {
2815         int rv;
2816
2817         if (snmp_mib_init((void __percpu **)net->mib.xfrm_statistics,
2818                           sizeof(struct linux_xfrm_mib),
2819                           __alignof__(struct linux_xfrm_mib)) < 0)
2820                 return -ENOMEM;
2821         rv = xfrm_proc_init(net);
2822         if (rv < 0)
2823                 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2824         return rv;
2825 }
2826
2827 static void xfrm_statistics_fini(struct net *net)
2828 {
2829         xfrm_proc_fini(net);
2830         snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2831 }
2832 #else
2833 static int __net_init xfrm_statistics_init(struct net *net)
2834 {
2835         return 0;
2836 }
2837
2838 static void xfrm_statistics_fini(struct net *net)
2839 {
2840 }
2841 #endif
2842
2843 static int __net_init xfrm_policy_init(struct net *net)
2844 {
2845         unsigned int hmask, sz;
2846         int dir;
2847
2848         if (net_eq(net, &init_net))
2849                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2850                                            sizeof(struct xfrm_dst),
2851                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2852                                            NULL);
2853
2854         hmask = 8 - 1;
2855         sz = (hmask+1) * sizeof(struct hlist_head);
2856
2857         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2858         if (!net->xfrm.policy_byidx)
2859                 goto out_byidx;
2860         net->xfrm.policy_idx_hmask = hmask;
2861
2862         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2863                 struct xfrm_policy_hash *htab;
2864
2865                 net->xfrm.policy_count[dir] = 0;
2866                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2867
2868                 htab = &net->xfrm.policy_bydst[dir];
2869                 htab->table = xfrm_hash_alloc(sz);
2870                 if (!htab->table)
2871                         goto out_bydst;
2872                 htab->hmask = hmask;
2873         }
2874
2875         INIT_LIST_HEAD(&net->xfrm.policy_all);
2876         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2877         if (net_eq(net, &init_net))
2878                 register_netdevice_notifier(&xfrm_dev_notifier);
2879         return 0;
2880
2881 out_bydst:
2882         for (dir--; dir >= 0; dir--) {
2883                 struct xfrm_policy_hash *htab;
2884
2885                 htab = &net->xfrm.policy_bydst[dir];
2886                 xfrm_hash_free(htab->table, sz);
2887         }
2888         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2889 out_byidx:
2890         return -ENOMEM;
2891 }
2892
2893 static void xfrm_policy_fini(struct net *net)
2894 {
2895         struct xfrm_audit audit_info;
2896         unsigned int sz;
2897         int dir;
2898
2899         flush_work(&net->xfrm.policy_hash_work);
2900 #ifdef CONFIG_XFRM_SUB_POLICY
2901         audit_info.loginuid = INVALID_UID;
2902         audit_info.sessionid = -1;
2903         audit_info.secid = 0;
2904         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info);
2905 #endif
2906         audit_info.loginuid = INVALID_UID;
2907         audit_info.sessionid = -1;
2908         audit_info.secid = 0;
2909         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info);
2910
2911         WARN_ON(!list_empty(&net->xfrm.policy_all));
2912
2913         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2914                 struct xfrm_policy_hash *htab;
2915
2916                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2917
2918                 htab = &net->xfrm.policy_bydst[dir];
2919                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2920                 WARN_ON(!hlist_empty(htab->table));
2921                 xfrm_hash_free(htab->table, sz);
2922         }
2923
2924         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2925         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2926         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2927 }
2928
2929 static int __net_init xfrm_net_init(struct net *net)
2930 {
2931         int rv;
2932
2933         rv = xfrm_statistics_init(net);
2934         if (rv < 0)
2935                 goto out_statistics;
2936         rv = xfrm_state_init(net);
2937         if (rv < 0)
2938                 goto out_state;
2939         rv = xfrm_policy_init(net);
2940         if (rv < 0)
2941                 goto out_policy;
2942         xfrm_dst_ops_init(net);
2943         rv = xfrm_sysctl_init(net);
2944         if (rv < 0)
2945                 goto out_sysctl;
2946         return 0;
2947
2948 out_sysctl:
2949         xfrm_policy_fini(net);
2950 out_policy:
2951         xfrm_state_fini(net);
2952 out_state:
2953         xfrm_statistics_fini(net);
2954 out_statistics:
2955         return rv;
2956 }
2957
2958 static void __net_exit xfrm_net_exit(struct net *net)
2959 {
2960         xfrm_sysctl_fini(net);
2961         xfrm_policy_fini(net);
2962         xfrm_state_fini(net);
2963         xfrm_statistics_fini(net);
2964 }
2965
2966 static struct pernet_operations __net_initdata xfrm_net_ops = {
2967         .init = xfrm_net_init,
2968         .exit = xfrm_net_exit,
2969 };
2970
2971 void __init xfrm_init(void)
2972 {
2973         register_pernet_subsys(&xfrm_net_ops);
2974         xfrm_input_init();
2975 }
2976
2977 #ifdef CONFIG_AUDITSYSCALL
2978 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2979                                          struct audit_buffer *audit_buf)
2980 {
2981         struct xfrm_sec_ctx *ctx = xp->security;
2982         struct xfrm_selector *sel = &xp->selector;
2983
2984         if (ctx)
2985                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2986                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2987
2988         switch(sel->family) {
2989         case AF_INET:
2990                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2991                 if (sel->prefixlen_s != 32)
2992                         audit_log_format(audit_buf, " src_prefixlen=%d",
2993                                          sel->prefixlen_s);
2994                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2995                 if (sel->prefixlen_d != 32)
2996                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2997                                          sel->prefixlen_d);
2998                 break;
2999         case AF_INET6:
3000                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3001                 if (sel->prefixlen_s != 128)
3002                         audit_log_format(audit_buf, " src_prefixlen=%d",
3003                                          sel->prefixlen_s);
3004                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3005                 if (sel->prefixlen_d != 128)
3006                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3007                                          sel->prefixlen_d);
3008                 break;
3009         }
3010 }
3011
3012 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
3013                            kuid_t auid, u32 sessionid, u32 secid)
3014 {
3015         struct audit_buffer *audit_buf;
3016
3017         audit_buf = xfrm_audit_start("SPD-add");
3018         if (audit_buf == NULL)
3019                 return;
3020         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
3021         audit_log_format(audit_buf, " res=%u", result);
3022         xfrm_audit_common_policyinfo(xp, audit_buf);
3023         audit_log_end(audit_buf);
3024 }
3025 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3026
3027 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3028                               kuid_t auid, u32 sessionid, u32 secid)
3029 {
3030         struct audit_buffer *audit_buf;
3031
3032         audit_buf = xfrm_audit_start("SPD-delete");
3033         if (audit_buf == NULL)
3034                 return;
3035         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
3036         audit_log_format(audit_buf, " res=%u", result);
3037         xfrm_audit_common_policyinfo(xp, audit_buf);
3038         audit_log_end(audit_buf);
3039 }
3040 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3041 #endif
3042
3043 #ifdef CONFIG_XFRM_MIGRATE
3044 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3045                                         const struct xfrm_selector *sel_tgt)
3046 {
3047         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3048                 if (sel_tgt->family == sel_cmp->family &&
3049                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3050                                     sel_cmp->family) &&
3051                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3052                                     sel_cmp->family) &&
3053                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3054                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3055                         return true;
3056                 }
3057         } else {
3058                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3059                         return true;
3060                 }
3061         }
3062         return false;
3063 }
3064
3065 static struct xfrm_policy * xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3066                                                      u8 dir, u8 type)
3067 {
3068         struct xfrm_policy *pol, *ret = NULL;
3069         struct hlist_head *chain;
3070         u32 priority = ~0U;
3071
3072         read_lock_bh(&xfrm_policy_lock);
3073         chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir);
3074         hlist_for_each_entry(pol, chain, bydst) {
3075                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3076                     pol->type == type) {
3077                         ret = pol;
3078                         priority = ret->priority;
3079                         break;
3080                 }
3081         }
3082         chain = &init_net.xfrm.policy_inexact[dir];
3083         hlist_for_each_entry(pol, chain, bydst) {
3084                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3085                     pol->type == type &&
3086                     pol->priority < priority) {
3087                         ret = pol;
3088                         break;
3089                 }
3090         }
3091
3092         if (ret)
3093                 xfrm_pol_hold(ret);
3094
3095         read_unlock_bh(&xfrm_policy_lock);
3096
3097         return ret;
3098 }
3099
3100 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3101 {
3102         int match = 0;
3103
3104         if (t->mode == m->mode && t->id.proto == m->proto &&
3105             (m->reqid == 0 || t->reqid == m->reqid)) {
3106                 switch (t->mode) {
3107                 case XFRM_MODE_TUNNEL:
3108                 case XFRM_MODE_BEET:
3109                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3110                                             m->old_family) &&
3111                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3112                                             m->old_family)) {
3113                                 match = 1;
3114                         }
3115                         break;
3116                 case XFRM_MODE_TRANSPORT:
3117                         /* in case of transport mode, template does not store
3118                            any IP addresses, hence we just compare mode and
3119                            protocol */
3120                         match = 1;
3121                         break;
3122                 default:
3123                         break;
3124                 }
3125         }
3126         return match;
3127 }
3128
3129 /* update endpoint address(es) of template(s) */
3130 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3131                                struct xfrm_migrate *m, int num_migrate)
3132 {
3133         struct xfrm_migrate *mp;
3134         int i, j, n = 0;
3135
3136         write_lock_bh(&pol->lock);
3137         if (unlikely(pol->walk.dead)) {
3138                 /* target policy has been deleted */
3139                 write_unlock_bh(&pol->lock);
3140                 return -ENOENT;
3141         }
3142
3143         for (i = 0; i < pol->xfrm_nr; i++) {
3144                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3145                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3146                                 continue;
3147                         n++;
3148                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3149                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3150                                 continue;
3151                         /* update endpoints */
3152                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3153                                sizeof(pol->xfrm_vec[i].id.daddr));
3154                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3155                                sizeof(pol->xfrm_vec[i].saddr));
3156                         pol->xfrm_vec[i].encap_family = mp->new_family;
3157                         /* flush bundles */
3158                         atomic_inc(&pol->genid);
3159                 }
3160         }
3161
3162         write_unlock_bh(&pol->lock);
3163
3164         if (!n)
3165                 return -ENODATA;
3166
3167         return 0;
3168 }
3169
3170 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3171 {
3172         int i, j;
3173
3174         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3175                 return -EINVAL;
3176
3177         for (i = 0; i < num_migrate; i++) {
3178                 if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
3179                                     m[i].old_family) &&
3180                     xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
3181                                     m[i].old_family))
3182                         return -EINVAL;
3183                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3184                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3185                         return -EINVAL;
3186
3187                 /* check if there is any duplicated entry */
3188                 for (j = i + 1; j < num_migrate; j++) {
3189                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3190                                     sizeof(m[i].old_daddr)) &&
3191                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3192                                     sizeof(m[i].old_saddr)) &&
3193                             m[i].proto == m[j].proto &&
3194                             m[i].mode == m[j].mode &&
3195                             m[i].reqid == m[j].reqid &&
3196                             m[i].old_family == m[j].old_family)
3197                                 return -EINVAL;
3198                 }
3199         }
3200
3201         return 0;
3202 }
3203
3204 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3205                  struct xfrm_migrate *m, int num_migrate,
3206                  struct xfrm_kmaddress *k)
3207 {
3208         int i, err, nx_cur = 0, nx_new = 0;
3209         struct xfrm_policy *pol = NULL;
3210         struct xfrm_state *x, *xc;
3211         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3212         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3213         struct xfrm_migrate *mp;
3214
3215         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3216                 goto out;
3217
3218         /* Stage 1 - find policy */
3219         if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
3220                 err = -ENOENT;
3221                 goto out;
3222         }
3223
3224         /* Stage 2 - find and update state(s) */
3225         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3226                 if ((x = xfrm_migrate_state_find(mp))) {
3227                         x_cur[nx_cur] = x;
3228                         nx_cur++;
3229                         if ((xc = xfrm_state_migrate(x, mp))) {
3230                                 x_new[nx_new] = xc;
3231                                 nx_new++;
3232                         } else {
3233                                 err = -ENODATA;
3234                                 goto restore_state;
3235                         }
3236                 }
3237         }
3238
3239         /* Stage 3 - update policy */
3240         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3241                 goto restore_state;
3242
3243         /* Stage 4 - delete old state(s) */
3244         if (nx_cur) {
3245                 xfrm_states_put(x_cur, nx_cur);
3246                 xfrm_states_delete(x_cur, nx_cur);
3247         }
3248
3249         /* Stage 5 - announce */
3250         km_migrate(sel, dir, type, m, num_migrate, k);
3251
3252         xfrm_pol_put(pol);
3253
3254         return 0;
3255 out:
3256         return err;
3257
3258 restore_state:
3259         if (pol)
3260                 xfrm_pol_put(pol);
3261         if (nx_cur)
3262                 xfrm_states_put(x_cur, nx_cur);
3263         if (nx_new)
3264                 xfrm_states_delete(x_new, nx_new);
3265
3266         return err;
3267 }
3268 EXPORT_SYMBOL(xfrm_migrate);
3269 #endif