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/cpu.h>
  28 #include <linux/audit.h>
  29 #include <net/dst.h>
  30 #include <net/flow.h>
  31 #include <net/xfrm.h>
  32 #include <net/ip.h>
  33 #ifdef CONFIG_XFRM_STATISTICS
  34 #include <net/snmp.h>
  35 #endif
  36
  37 #include "xfrm_hash.h"
  38
  39 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  40 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  41 #define XFRM_MAX_QUEUE_LEN      100
  42
  43 struct xfrm_flo {
  44         struct dst_entry *dst_orig;
  45         u8 flags;
  46 };
  47
  48 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
  49 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
  50
  51 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
  52 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
  53                                                 __read_mostly;
  54
  55 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
  56 static __read_mostly seqcount_t xfrm_policy_hash_generation;
  57
  58 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
  59 static int stale_bundle(struct dst_entry *dst);
  60 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
  61 static void xfrm_policy_queue_process(struct timer_list *t);
  62
  63 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
  64 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
  65                                                 int dir);
  66
  67 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
  68 {
  69         return refcount_inc_not_zero(&policy->refcnt);
  70 }
  71
  72 static inline bool
  73 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  74 {
  75         const struct flowi4 *fl4 = &fl->u.ip4;
  76
  77         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
  78                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
  79                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
  80                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
  81                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
  82                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
  83 }
  84
  85 static inline bool
  86 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  87 {
  88         const struct flowi6 *fl6 = &fl->u.ip6;
  89
  90         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
  91                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
  92                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
  93                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
  94                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
  95                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
  96 }
  97
  98 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
  99                          unsigned short family)
 100 {
 101         switch (family) {
 102         case AF_INET:
 103                 return __xfrm4_selector_match(sel, fl);
 104         case AF_INET6:
 105                 return __xfrm6_selector_match(sel, fl);
 106         }
 107         return false;
 108 }
 109
 110 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 111 {
 112         const struct xfrm_policy_afinfo *afinfo;
 113
 114         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 115                 return NULL;
 116         rcu_read_lock();
 117         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 118         if (unlikely(!afinfo))
 119                 rcu_read_unlock();
 120         return afinfo;
 121 }
 122
 123 /* Called with rcu_read_lock(). */
 124 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 125 {
 126         return rcu_dereference(xfrm_if_cb);
 127 }
 128
 129 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 130                                     const xfrm_address_t *saddr,
 131                                     const xfrm_address_t *daddr,
 132                                     int family, u32 mark)
 133 {
 134         const struct xfrm_policy_afinfo *afinfo;
 135         struct dst_entry *dst;
 136
 137         afinfo = xfrm_policy_get_afinfo(family);
 138         if (unlikely(afinfo == NULL))
 139                 return ERR_PTR(-EAFNOSUPPORT);
 140
 141         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 142
 143         rcu_read_unlock();
 144
 145         return dst;
 146 }
 147 EXPORT_SYMBOL(__xfrm_dst_lookup);
 148
 149 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 150                                                 int tos, int oif,
 151                                                 xfrm_address_t *prev_saddr,
 152                                                 xfrm_address_t *prev_daddr,
 153                                                 int family, u32 mark)
 154 {
 155         struct net *net = xs_net(x);
 156         xfrm_address_t *saddr = &x->props.saddr;
 157         xfrm_address_t *daddr = &x->id.daddr;
 158         struct dst_entry *dst;
 159
 160         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 161                 saddr = x->coaddr;
 162                 daddr = prev_daddr;
 163         }
 164         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 165                 saddr = prev_saddr;
 166                 daddr = x->coaddr;
 167         }
 168
 169         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 170
 171         if (!IS_ERR(dst)) {
 172                 if (prev_saddr != saddr)
 173                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 174                 if (prev_daddr != daddr)
 175                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 176         }
 177
 178         return dst;
 179 }
 180
 181 static inline unsigned long make_jiffies(long secs)
 182 {
 183         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 184                 return MAX_SCHEDULE_TIMEOUT-1;
 185         else
 186                 return secs*HZ;
 187 }
 188
 189 static void xfrm_policy_timer(struct timer_list *t)
 190 {
 191         struct xfrm_policy *xp = from_timer(xp, t, timer);
 192         time64_t now = ktime_get_real_seconds();
 193         time64_t next = TIME64_MAX;
 194         int warn = 0;
 195         int dir;
 196
 197         read_lock(&xp->lock);
 198
 199         if (unlikely(xp->walk.dead))
 200                 goto out;
 201
 202         dir = xfrm_policy_id2dir(xp->index);
 203
 204         if (xp->lft.hard_add_expires_seconds) {
 205                 time64_t tmo = xp->lft.hard_add_expires_seconds +
 206                         xp->curlft.add_time - now;
 207                 if (tmo <= 0)
 208                         goto expired;
 209                 if (tmo < next)
 210                         next = tmo;
 211         }
 212         if (xp->lft.hard_use_expires_seconds) {
 213                 time64_t tmo = xp->lft.hard_use_expires_seconds +
 214                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 215                 if (tmo <= 0)
 216                         goto expired;
 217                 if (tmo < next)
 218                         next = tmo;
 219         }
 220         if (xp->lft.soft_add_expires_seconds) {
 221                 time64_t tmo = xp->lft.soft_add_expires_seconds +
 222                         xp->curlft.add_time - now;
 223                 if (tmo <= 0) {
 224                         warn = 1;
 225                         tmo = XFRM_KM_TIMEOUT;
 226                 }
 227                 if (tmo < next)
 228                         next = tmo;
 229         }
 230         if (xp->lft.soft_use_expires_seconds) {
 231                 time64_t tmo = xp->lft.soft_use_expires_seconds +
 232                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 233                 if (tmo <= 0) {
 234                         warn = 1;
 235                         tmo = XFRM_KM_TIMEOUT;
 236                 }
 237                 if (tmo < next)
 238                         next = tmo;
 239         }
 240
 241         if (warn)
 242                 km_policy_expired(xp, dir, 0, 0);
 243         if (next != TIME64_MAX &&
 244             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 245                 xfrm_pol_hold(xp);
 246
 247 out:
 248         read_unlock(&xp->lock);
 249         xfrm_pol_put(xp);
 250         return;
 251
 252 expired:
 253         read_unlock(&xp->lock);
 254         if (!xfrm_policy_delete(xp, dir))
 255                 km_policy_expired(xp, dir, 1, 0);
 256         xfrm_pol_put(xp);
 257 }
 258
 259 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 260  * SPD calls.
 261  */
 262
 263 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 264 {
 265         struct xfrm_policy *policy;
 266
 267         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 268
 269         if (policy) {
 270                 write_pnet(&policy->xp_net, net);
 271                 INIT_LIST_HEAD(&policy->walk.all);
 272                 INIT_HLIST_NODE(&policy->bydst);
 273                 INIT_HLIST_NODE(&policy->byidx);
 274                 rwlock_init(&policy->lock);
 275                 refcount_set(&policy->refcnt, 1);
 276                 skb_queue_head_init(&policy->polq.hold_queue);
 277                 timer_setup(&policy->timer, xfrm_policy_timer, 0);
 278                 timer_setup(&policy->polq.hold_timer,
 279                             xfrm_policy_queue_process, 0);
 280         }
 281         return policy;
 282 }
 283 EXPORT_SYMBOL(xfrm_policy_alloc);
 284
 285 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 286 {
 287         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 288
 289         security_xfrm_policy_free(policy->security);
 290         kfree(policy);
 291 }
 292
 293 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 294
 295 void xfrm_policy_destroy(struct xfrm_policy *policy)
 296 {
 297         BUG_ON(!policy->walk.dead);
 298
 299         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 300                 BUG();
 301
 302         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 303 }
 304 EXPORT_SYMBOL(xfrm_policy_destroy);
 305
 306 /* Rule must be locked. Release descendant resources, announce
 307  * entry dead. The rule must be unlinked from lists to the moment.
 308  */
 309
 310 static void xfrm_policy_kill(struct xfrm_policy *policy)
 311 {
 312         policy->walk.dead = 1;
 313
 314         atomic_inc(&policy->genid);
 315
 316         if (del_timer(&policy->polq.hold_timer))
 317                 xfrm_pol_put(policy);
 318         skb_queue_purge(&policy->polq.hold_queue);
 319
 320         if (del_timer(&policy->timer))
 321                 xfrm_pol_put(policy);
 322
 323         xfrm_pol_put(policy);
 324 }
 325
 326 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 327
 328 static inline unsigned int idx_hash(struct net *net, u32 index)
 329 {
 330         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 331 }
 332
 333 /* calculate policy hash thresholds */
 334 static void __get_hash_thresh(struct net *net,
 335                               unsigned short family, int dir,
 336                               u8 *dbits, u8 *sbits)
 337 {
 338         switch (family) {
 339         case AF_INET:
 340                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 341                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 342                 break;
 343
 344         case AF_INET6:
 345                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 346                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 347                 break;
 348
 349         default:
 350                 *dbits = 0;
 351                 *sbits = 0;
 352         }
 353 }
 354
 355 static struct hlist_head *policy_hash_bysel(struct net *net,
 356                                             const struct xfrm_selector *sel,
 357                                             unsigned short family, int dir)
 358 {
 359         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 360         unsigned int hash;
 361         u8 dbits;
 362         u8 sbits;
 363
 364         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 365         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 366
 367         if (hash == hmask + 1)
 368                 return &net->xfrm.policy_inexact[dir];
 369
 370         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 371                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 372 }
 373
 374 static struct hlist_head *policy_hash_direct(struct net *net,
 375                                              const xfrm_address_t *daddr,
 376                                              const xfrm_address_t *saddr,
 377                                              unsigned short family, int dir)
 378 {
 379         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 380         unsigned int hash;
 381         u8 dbits;
 382         u8 sbits;
 383
 384         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 385         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 386
 387         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 388                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 389 }
 390
 391 static void xfrm_dst_hash_transfer(struct net *net,
 392                                    struct hlist_head *list,
 393                                    struct hlist_head *ndsttable,
 394                                    unsigned int nhashmask,
 395                                    int dir)
 396 {
 397         struct hlist_node *tmp, *entry0 = NULL;
 398         struct xfrm_policy *pol;
 399         unsigned int h0 = 0;
 400         u8 dbits;
 401         u8 sbits;
 402
 403 redo:
 404         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 405                 unsigned int h;
 406
 407                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 408                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 409                                 pol->family, nhashmask, dbits, sbits);
 410                 if (!entry0) {
 411                         hlist_del_rcu(&pol->bydst);
 412                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 413                         h0 = h;
 414                 } else {
 415                         if (h != h0)
 416                                 continue;
 417                         hlist_del_rcu(&pol->bydst);
 418                         hlist_add_behind_rcu(&pol->bydst, entry0);
 419                 }
 420                 entry0 = &pol->bydst;
 421         }
 422         if (!hlist_empty(list)) {
 423                 entry0 = NULL;
 424                 goto redo;
 425         }
 426 }
 427
 428 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 429                                    struct hlist_head *nidxtable,
 430                                    unsigned int nhashmask)
 431 {
 432         struct hlist_node *tmp;
 433         struct xfrm_policy *pol;
 434
 435         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 436                 unsigned int h;
 437
 438                 h = __idx_hash(pol->index, nhashmask);
 439                 hlist_add_head(&pol->byidx, nidxtable+h);
 440         }
 441 }
 442
 443 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 444 {
 445         return ((old_hmask + 1) << 1) - 1;
 446 }
 447
 448 static void xfrm_bydst_resize(struct net *net, int dir)
 449 {
 450         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 451         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 452         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 453         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 454         struct hlist_head *odst;
 455         int i;
 456
 457         if (!ndst)
 458                 return;
 459
 460         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 461         write_seqcount_begin(&xfrm_policy_hash_generation);
 462
 463         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 464                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 465
 466         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 467                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 468
 469         for (i = hmask; i >= 0; i--)
 470                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 471
 472         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 473         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 474
 475         write_seqcount_end(&xfrm_policy_hash_generation);
 476         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 477
 478         synchronize_rcu();
 479
 480         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 481 }
 482
 483 static void xfrm_byidx_resize(struct net *net, int total)
 484 {
 485         unsigned int hmask = net->xfrm.policy_idx_hmask;
 486         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 487         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 488         struct hlist_head *oidx = net->xfrm.policy_byidx;
 489         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 490         int i;
 491
 492         if (!nidx)
 493                 return;
 494
 495         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 496
 497         for (i = hmask; i >= 0; i--)
 498                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 499
 500         net->xfrm.policy_byidx = nidx;
 501         net->xfrm.policy_idx_hmask = nhashmask;
 502
 503         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 504
 505         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 506 }
 507
 508 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 509 {
 510         unsigned int cnt = net->xfrm.policy_count[dir];
 511         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 512
 513         if (total)
 514                 *total += cnt;
 515
 516         if ((hmask + 1) < xfrm_policy_hashmax &&
 517             cnt > hmask)
 518                 return 1;
 519
 520         return 0;
 521 }
 522
 523 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 524 {
 525         unsigned int hmask = net->xfrm.policy_idx_hmask;
 526
 527         if ((hmask + 1) < xfrm_policy_hashmax &&
 528             total > hmask)
 529                 return 1;
 530
 531         return 0;
 532 }
 533
 534 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 535 {
 536         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 537         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 538         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 539         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 540         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 541         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 542         si->spdhcnt = net->xfrm.policy_idx_hmask;
 543         si->spdhmcnt = xfrm_policy_hashmax;
 544 }
 545 EXPORT_SYMBOL(xfrm_spd_getinfo);
 546
 547 static DEFINE_MUTEX(hash_resize_mutex);
 548 static void xfrm_hash_resize(struct work_struct *work)
 549 {
 550         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 551         int dir, total;
 552
 553         mutex_lock(&hash_resize_mutex);
 554
 555         total = 0;
 556         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 557                 if (xfrm_bydst_should_resize(net, dir, &total))
 558                         xfrm_bydst_resize(net, dir);
 559         }
 560         if (xfrm_byidx_should_resize(net, total))
 561                 xfrm_byidx_resize(net, total);
 562
 563         mutex_unlock(&hash_resize_mutex);
 564 }
 565
 566 static void xfrm_hash_rebuild(struct work_struct *work)
 567 {
 568         struct net *net = container_of(work, struct net,
 569                                        xfrm.policy_hthresh.work);
 570         unsigned int hmask;
 571         struct xfrm_policy *pol;
 572         struct xfrm_policy *policy;
 573         struct hlist_head *chain;
 574         struct hlist_head *odst;
 575         struct hlist_node *newpos;
 576         int i;
 577         int dir;
 578         unsigned seq;
 579         u8 lbits4, rbits4, lbits6, rbits6;
 580
 581         mutex_lock(&hash_resize_mutex);
 582
 583         /* read selector prefixlen thresholds */
 584         do {
 585                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
 586
 587                 lbits4 = net->xfrm.policy_hthresh.lbits4;
 588                 rbits4 = net->xfrm.policy_hthresh.rbits4;
 589                 lbits6 = net->xfrm.policy_hthresh.lbits6;
 590                 rbits6 = net->xfrm.policy_hthresh.rbits6;
 591         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
 592
 593         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 594
 595         /* reset the bydst and inexact table in all directions */
 596         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 597                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
 598                 hmask = net->xfrm.policy_bydst[dir].hmask;
 599                 odst = net->xfrm.policy_bydst[dir].table;
 600                 for (i = hmask; i >= 0; i--)
 601                         INIT_HLIST_HEAD(odst + i);
 602                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
 603                         /* dir out => dst = remote, src = local */
 604                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
 605                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
 606                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
 607                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
 608                 } else {
 609                         /* dir in/fwd => dst = local, src = remote */
 610                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
 611                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
 612                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
 613                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
 614                 }
 615         }
 616
 617         /* re-insert all policies by order of creation */
 618         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 619                 if (policy->walk.dead ||
 620                     xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
 621                         /* skip socket policies */
 622                         continue;
 623                 }
 624                 newpos = NULL;
 625                 chain = policy_hash_bysel(net, &policy->selector,
 626                                           policy->family,
 627                                           xfrm_policy_id2dir(policy->index));
 628                 hlist_for_each_entry(pol, chain, bydst) {
 629                         if (policy->priority >= pol->priority)
 630                                 newpos = &pol->bydst;
 631                         else
 632                                 break;
 633                 }
 634                 if (newpos)
 635                         hlist_add_behind_rcu(&policy->bydst, newpos);
 636                 else
 637                         hlist_add_head_rcu(&policy->bydst, chain);
 638         }
 639
 640         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 641
 642         mutex_unlock(&hash_resize_mutex);
 643 }
 644
 645 void xfrm_policy_hash_rebuild(struct net *net)
 646 {
 647         schedule_work(&net->xfrm.policy_hthresh.work);
 648 }
 649 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
 650
 651 /* Generate new index... KAME seems to generate them ordered by cost
 652  * of an absolute inpredictability of ordering of rules. This will not pass. */
 653 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
 654 {
 655         static u32 idx_generator;
 656
 657         for (;;) {
 658                 struct hlist_head *list;
 659                 struct xfrm_policy *p;
 660                 u32 idx;
 661                 int found;
 662
 663                 if (!index) {
 664                         idx = (idx_generator | dir);
 665                         idx_generator += 8;
 666                 } else {
 667                         idx = index;
 668                         index = 0;
 669                 }
 670
 671                 if (idx == 0)
 672                         idx = 8;
 673                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 674                 found = 0;
 675                 hlist_for_each_entry(p, list, byidx) {
 676                         if (p->index == idx) {
 677                                 found = 1;
 678                                 break;
 679                         }
 680                 }
 681                 if (!found)
 682                         return idx;
 683         }
 684 }
 685
 686 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 687 {
 688         u32 *p1 = (u32 *) s1;
 689         u32 *p2 = (u32 *) s2;
 690         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 691         int i;
 692
 693         for (i = 0; i < len; i++) {
 694                 if (p1[i] != p2[i])
 695                         return 1;
 696         }
 697
 698         return 0;
 699 }
 700
 701 static void xfrm_policy_requeue(struct xfrm_policy *old,
 702                                 struct xfrm_policy *new)
 703 {
 704         struct xfrm_policy_queue *pq = &old->polq;
 705         struct sk_buff_head list;
 706
 707         if (skb_queue_empty(&pq->hold_queue))
 708                 return;
 709
 710         __skb_queue_head_init(&list);
 711
 712         spin_lock_bh(&pq->hold_queue.lock);
 713         skb_queue_splice_init(&pq->hold_queue, &list);
 714         if (del_timer(&pq->hold_timer))
 715                 xfrm_pol_put(old);
 716         spin_unlock_bh(&pq->hold_queue.lock);
 717
 718         pq = &new->polq;
 719
 720         spin_lock_bh(&pq->hold_queue.lock);
 721         skb_queue_splice(&list, &pq->hold_queue);
 722         pq->timeout = XFRM_QUEUE_TMO_MIN;
 723         if (!mod_timer(&pq->hold_timer, jiffies))
 724                 xfrm_pol_hold(new);
 725         spin_unlock_bh(&pq->hold_queue.lock);
 726 }
 727
 728 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
 729                                    struct xfrm_policy *pol)
 730 {
 731         u32 mark = policy->mark.v & policy->mark.m;
 732
 733         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
 734                 return true;
 735
 736         if ((mark & pol->mark.m) == pol->mark.v &&
 737             policy->priority == pol->priority)
 738                 return true;
 739
 740         return false;
 741 }
 742
 743 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 744 {
 745         struct net *net = xp_net(policy);
 746         struct xfrm_policy *pol;
 747         struct xfrm_policy *delpol;
 748         struct hlist_head *chain;
 749         struct hlist_node *newpos;
 750
 751         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 752         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 753         delpol = NULL;
 754         newpos = NULL;
 755         hlist_for_each_entry(pol, chain, bydst) {
 756                 if (pol->type == policy->type &&
 757                     pol->if_id == policy->if_id &&
 758                     !selector_cmp(&pol->selector, &policy->selector) &&
 759                     xfrm_policy_mark_match(policy, pol) &&
 760                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 761                     !WARN_ON(delpol)) {
 762                         if (excl) {
 763                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 764                                 return -EEXIST;
 765                         }
 766                         delpol = pol;
 767                         if (policy->priority > pol->priority)
 768                                 continue;
 769                 } else if (policy->priority >= pol->priority) {
 770                         newpos = &pol->bydst;
 771                         continue;
 772                 }
 773                 if (delpol)
 774                         break;
 775         }
 776         if (newpos)
 777                 hlist_add_behind_rcu(&policy->bydst, newpos);
 778         else
 779                 hlist_add_head_rcu(&policy->bydst, chain);
 780         __xfrm_policy_link(policy, dir);
 781
 782         /* After previous checking, family can either be AF_INET or AF_INET6 */
 783         if (policy->family == AF_INET)
 784                 rt_genid_bump_ipv4(net);
 785         else
 786                 rt_genid_bump_ipv6(net);
 787
 788         if (delpol) {
 789                 xfrm_policy_requeue(delpol, policy);
 790                 __xfrm_policy_unlink(delpol, dir);
 791         }
 792         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
 793         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 794         policy->curlft.add_time = ktime_get_real_seconds();
 795         policy->curlft.use_time = 0;
 796         if (!mod_timer(&policy->timer, jiffies + HZ))
 797                 xfrm_pol_hold(policy);
 798         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 799
 800         if (delpol)
 801                 xfrm_policy_kill(delpol);
 802         else if (xfrm_bydst_should_resize(net, dir, NULL))
 803                 schedule_work(&net->xfrm.policy_hash_work);
 804
 805         return 0;
 806 }
 807 EXPORT_SYMBOL(xfrm_policy_insert);
 808
 809 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id,
 810                                           u8 type, int dir,
 811                                           struct xfrm_selector *sel,
 812                                           struct xfrm_sec_ctx *ctx, int delete,
 813                                           int *err)
 814 {
 815         struct xfrm_policy *pol, *ret;
 816         struct hlist_head *chain;
 817
 818         *err = 0;
 819         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 820         chain = policy_hash_bysel(net, sel, sel->family, dir);
 821         ret = NULL;
 822         hlist_for_each_entry(pol, chain, bydst) {
 823                 if (pol->type == type &&
 824                     pol->if_id == if_id &&
 825                     (mark & pol->mark.m) == pol->mark.v &&
 826                     !selector_cmp(sel, &pol->selector) &&
 827                     xfrm_sec_ctx_match(ctx, pol->security)) {
 828                         xfrm_pol_hold(pol);
 829                         if (delete) {
 830                                 *err = security_xfrm_policy_delete(
 831                                                                 pol->security);
 832                                 if (*err) {
 833                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 834                                         return pol;
 835                                 }
 836                                 __xfrm_policy_unlink(pol, dir);
 837                         }
 838                         ret = pol;
 839                         break;
 840                 }
 841         }
 842         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 843
 844         if (ret && delete)
 845                 xfrm_policy_kill(ret);
 846         return ret;
 847 }
 848 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 849
 850 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id,
 851                                      u8 type, int dir, u32 id, int delete,
 852                                      int *err)
 853 {
 854         struct xfrm_policy *pol, *ret;
 855         struct hlist_head *chain;
 856
 857         *err = -ENOENT;
 858         if (xfrm_policy_id2dir(id) != dir)
 859                 return NULL;
 860
 861         *err = 0;
 862         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 863         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 864         ret = NULL;
 865         hlist_for_each_entry(pol, chain, byidx) {
 866                 if (pol->type == type && pol->index == id &&
 867                     pol->if_id == if_id &&
 868                     (mark & pol->mark.m) == pol->mark.v) {
 869                         xfrm_pol_hold(pol);
 870                         if (delete) {
 871                                 *err = security_xfrm_policy_delete(
 872                                                                 pol->security);
 873                                 if (*err) {
 874                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 875                                         return pol;
 876                                 }
 877                                 __xfrm_policy_unlink(pol, dir);
 878                         }
 879                         ret = pol;
 880                         break;
 881                 }
 882         }
 883         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 884
 885         if (ret && delete)
 886                 xfrm_policy_kill(ret);
 887         return ret;
 888 }
 889 EXPORT_SYMBOL(xfrm_policy_byid);
 890
 891 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 892 static inline int
 893 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 894 {
 895         int dir, err = 0;
 896
 897         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 898                 struct xfrm_policy *pol;
 899                 int i;
 900
 901                 hlist_for_each_entry(pol,
 902                                      &net->xfrm.policy_inexact[dir], bydst) {
 903                         if (pol->type != type)
 904                                 continue;
 905                         err = security_xfrm_policy_delete(pol->security);
 906                         if (err) {
 907                                 xfrm_audit_policy_delete(pol, 0, task_valid);
 908                                 return err;
 909                         }
 910                 }
 911                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 912                         hlist_for_each_entry(pol,
 913                                              net->xfrm.policy_bydst[dir].table + i,
 914                                              bydst) {
 915                                 if (pol->type != type)
 916                                         continue;
 917                                 err = security_xfrm_policy_delete(
 918                                                                 pol->security);
 919                                 if (err) {
 920                                         xfrm_audit_policy_delete(pol, 0,
 921                                                                  task_valid);
 922                                         return err;
 923                                 }
 924                         }
 925                 }
 926         }
 927         return err;
 928 }
 929 #else
 930 static inline int
 931 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 932 {
 933         return 0;
 934 }
 935 #endif
 936
 937 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
 938 {
 939         int dir, err = 0, cnt = 0;
 940
 941         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 942
 943         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
 944         if (err)
 945                 goto out;
 946
 947         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 948                 struct xfrm_policy *pol;
 949                 int i;
 950
 951         again1:
 952                 hlist_for_each_entry(pol,
 953                                      &net->xfrm.policy_inexact[dir], bydst) {
 954                         if (pol->type != type)
 955                                 continue;
 956                         __xfrm_policy_unlink(pol, dir);
 957                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 958                         cnt++;
 959
 960                         xfrm_audit_policy_delete(pol, 1, task_valid);
 961
 962                         xfrm_policy_kill(pol);
 963
 964                         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 965                         goto again1;
 966                 }
 967
 968                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 969         again2:
 970                         hlist_for_each_entry(pol,
 971                                              net->xfrm.policy_bydst[dir].table + i,
 972                                              bydst) {
 973                                 if (pol->type != type)
 974                                         continue;
 975                                 __xfrm_policy_unlink(pol, dir);
 976                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 977                                 cnt++;
 978
 979                                 xfrm_audit_policy_delete(pol, 1, task_valid);
 980                                 xfrm_policy_kill(pol);
 981
 982                                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 983                                 goto again2;
 984                         }
 985                 }
 986
 987         }
 988         if (!cnt)
 989                 err = -ESRCH;
 990 out:
 991         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 992         return err;
 993 }
 994 EXPORT_SYMBOL(xfrm_policy_flush);
 995
 996 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 997                      int (*func)(struct xfrm_policy *, int, int, void*),
 998                      void *data)
 999 {
1000         struct xfrm_policy *pol;
1001         struct xfrm_policy_walk_entry *x;
1002         int error = 0;
1003
1004         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1005             walk->type != XFRM_POLICY_TYPE_ANY)
1006                 return -EINVAL;
1007
1008         if (list_empty(&walk->walk.all) && walk->seq != 0)
1009                 return 0;
1010
1011         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1012         if (list_empty(&walk->walk.all))
1013                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1014         else
1015                 x = list_first_entry(&walk->walk.all,
1016                                      struct xfrm_policy_walk_entry, all);
1017
1018         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1019                 if (x->dead)
1020                         continue;
1021                 pol = container_of(x, struct xfrm_policy, walk);
1022                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1023                     walk->type != pol->type)
1024                         continue;
1025                 error = func(pol, xfrm_policy_id2dir(pol->index),
1026                              walk->seq, data);
1027                 if (error) {
1028                         list_move_tail(&walk->walk.all, &x->all);
1029                         goto out;
1030                 }
1031                 walk->seq++;
1032         }
1033         if (walk->seq == 0) {
1034                 error = -ENOENT;
1035                 goto out;
1036         }
1037         list_del_init(&walk->walk.all);
1038 out:
1039         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1040         return error;
1041 }
1042 EXPORT_SYMBOL(xfrm_policy_walk);
1043
1044 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1045 {
1046         INIT_LIST_HEAD(&walk->walk.all);
1047         walk->walk.dead = 1;
1048         walk->type = type;
1049         walk->seq = 0;
1050 }
1051 EXPORT_SYMBOL(xfrm_policy_walk_init);
1052
1053 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1054 {
1055         if (list_empty(&walk->walk.all))
1056                 return;
1057
1058         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1059         list_del(&walk->walk.all);
1060         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1061 }
1062 EXPORT_SYMBOL(xfrm_policy_walk_done);
1063
1064 /*
1065  * Find policy to apply to this flow.
1066  *
1067  * Returns 0 if policy found, else an -errno.
1068  */
1069 static int xfrm_policy_match(const struct xfrm_policy *pol,
1070                              const struct flowi *fl,
1071                              u8 type, u16 family, int dir, u32 if_id)
1072 {
1073         const struct xfrm_selector *sel = &pol->selector;
1074         int ret = -ESRCH;
1075         bool match;
1076
1077         if (pol->family != family ||
1078             pol->if_id != if_id ||
1079             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1080             pol->type != type)
1081                 return ret;
1082
1083         match = xfrm_selector_match(sel, fl, family);
1084         if (match)
1085                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1086                                                   dir);
1087
1088         return ret;
1089 }
1090
1091 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1092                                                      const struct flowi *fl,
1093                                                      u16 family, u8 dir,
1094                                                      u32 if_id)
1095 {
1096         int err;
1097         struct xfrm_policy *pol, *ret;
1098         const xfrm_address_t *daddr, *saddr;
1099         struct hlist_head *chain;
1100         unsigned int sequence;
1101         u32 priority;
1102
1103         daddr = xfrm_flowi_daddr(fl, family);
1104         saddr = xfrm_flowi_saddr(fl, family);
1105         if (unlikely(!daddr || !saddr))
1106                 return NULL;
1107
1108         rcu_read_lock();
1109  retry:
1110         do {
1111                 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1112                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1113         } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1114
1115         priority = ~0U;
1116         ret = NULL;
1117         hlist_for_each_entry_rcu(pol, chain, bydst) {
1118                 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
1119                 if (err) {
1120                         if (err == -ESRCH)
1121                                 continue;
1122                         else {
1123                                 ret = ERR_PTR(err);
1124                                 goto fail;
1125                         }
1126                 } else {
1127                         ret = pol;
1128                         priority = ret->priority;
1129                         break;
1130                 }
1131         }
1132         chain = &net->xfrm.policy_inexact[dir];
1133         hlist_for_each_entry_rcu(pol, chain, bydst) {
1134                 if ((pol->priority >= priority) && ret)
1135                         break;
1136
1137                 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
1138                 if (err) {
1139                         if (err == -ESRCH)
1140                                 continue;
1141                         else {
1142                                 ret = ERR_PTR(err);
1143                                 goto fail;
1144                         }
1145                 } else {
1146                         ret = pol;
1147                         break;
1148                 }
1149         }
1150
1151         if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1152                 goto retry;
1153
1154         if (ret && !xfrm_pol_hold_rcu(ret))
1155                 goto retry;
1156 fail:
1157         rcu_read_unlock();
1158
1159         return ret;
1160 }
1161
1162 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
1163                                               const struct flowi *fl,
1164                                               u16 family, u8 dir, u32 if_id)
1165 {
1166 #ifdef CONFIG_XFRM_SUB_POLICY
1167         struct xfrm_policy *pol;
1168
1169         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
1170                                         dir, if_id);
1171         if (pol != NULL)
1172                 return pol;
1173 #endif
1174         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
1175                                          dir, if_id);
1176 }
1177
1178 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1179                                                  const struct flowi *fl,
1180                                                  u16 family, u32 if_id)
1181 {
1182         struct xfrm_policy *pol;
1183
1184         rcu_read_lock();
1185  again:
1186         pol = rcu_dereference(sk->sk_policy[dir]);
1187         if (pol != NULL) {
1188                 bool match;
1189                 int err = 0;
1190
1191                 if (pol->family != family) {
1192                         pol = NULL;
1193                         goto out;
1194                 }
1195
1196                 match = xfrm_selector_match(&pol->selector, fl, family);
1197                 if (match) {
1198                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
1199                             pol->if_id != if_id) {
1200                                 pol = NULL;
1201                                 goto out;
1202                         }
1203                         err = security_xfrm_policy_lookup(pol->security,
1204                                                       fl->flowi_secid,
1205                                                       dir);
1206                         if (!err) {
1207                                 if (!xfrm_pol_hold_rcu(pol))
1208                                         goto again;
1209                         } else if (err == -ESRCH) {
1210                                 pol = NULL;
1211                         } else {
1212                                 pol = ERR_PTR(err);
1213                         }
1214                 } else
1215                         pol = NULL;
1216         }
1217 out:
1218         rcu_read_unlock();
1219         return pol;
1220 }
1221
1222 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1223 {
1224         struct net *net = xp_net(pol);
1225
1226         list_add(&pol->walk.all, &net->xfrm.policy_all);
1227         net->xfrm.policy_count[dir]++;
1228         xfrm_pol_hold(pol);
1229 }
1230
1231 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1232                                                 int dir)
1233 {
1234         struct net *net = xp_net(pol);
1235
1236         if (list_empty(&pol->walk.all))
1237                 return NULL;
1238
1239         /* Socket policies are not hashed. */
1240         if (!hlist_unhashed(&pol->bydst)) {
1241                 hlist_del_rcu(&pol->bydst);
1242                 hlist_del(&pol->byidx);
1243         }
1244
1245         list_del_init(&pol->walk.all);
1246         net->xfrm.policy_count[dir]--;
1247
1248         return pol;
1249 }
1250
1251 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1252 {
1253         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1254 }
1255
1256 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1257 {
1258         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1259 }
1260
1261 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1262 {
1263         struct net *net = xp_net(pol);
1264
1265         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1266         pol = __xfrm_policy_unlink(pol, dir);
1267         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1268         if (pol) {
1269                 xfrm_policy_kill(pol);
1270                 return 0;
1271         }
1272         return -ENOENT;
1273 }
1274 EXPORT_SYMBOL(xfrm_policy_delete);
1275
1276 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1277 {
1278         struct net *net = sock_net(sk);
1279         struct xfrm_policy *old_pol;
1280
1281 #ifdef CONFIG_XFRM_SUB_POLICY
1282         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1283                 return -EINVAL;
1284 #endif
1285
1286         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1287         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1288                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1289         if (pol) {
1290                 pol->curlft.add_time = ktime_get_real_seconds();
1291                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1292                 xfrm_sk_policy_link(pol, dir);
1293         }
1294         rcu_assign_pointer(sk->sk_policy[dir], pol);
1295         if (old_pol) {
1296                 if (pol)
1297                         xfrm_policy_requeue(old_pol, pol);
1298
1299                 /* Unlinking succeeds always. This is the only function
1300                  * allowed to delete or replace socket policy.
1301                  */
1302                 xfrm_sk_policy_unlink(old_pol, dir);
1303         }
1304         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1305
1306         if (old_pol) {
1307                 xfrm_policy_kill(old_pol);
1308         }
1309         return 0;
1310 }
1311
1312 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1313 {
1314         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1315         struct net *net = xp_net(old);
1316
1317         if (newp) {
1318                 newp->selector = old->selector;
1319                 if (security_xfrm_policy_clone(old->security,
1320                                                &newp->security)) {
1321                         kfree(newp);
1322                         return NULL;  /* ENOMEM */
1323                 }
1324                 newp->lft = old->lft;
1325                 newp->curlft = old->curlft;
1326                 newp->mark = old->mark;
1327                 newp->if_id = old->if_id;
1328                 newp->action = old->action;
1329                 newp->flags = old->flags;
1330                 newp->xfrm_nr = old->xfrm_nr;
1331                 newp->index = old->index;
1332                 newp->type = old->type;
1333                 newp->family = old->family;
1334                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1335                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1336                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1337                 xfrm_sk_policy_link(newp, dir);
1338                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1339                 xfrm_pol_put(newp);
1340         }
1341         return newp;
1342 }
1343
1344 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1345 {
1346         const struct xfrm_policy *p;
1347         struct xfrm_policy *np;
1348         int i, ret = 0;
1349
1350         rcu_read_lock();
1351         for (i = 0; i < 2; i++) {
1352                 p = rcu_dereference(osk->sk_policy[i]);
1353                 if (p) {
1354                         np = clone_policy(p, i);
1355                         if (unlikely(!np)) {
1356                                 ret = -ENOMEM;
1357                                 break;
1358                         }
1359                         rcu_assign_pointer(sk->sk_policy[i], np);
1360                 }
1361         }
1362         rcu_read_unlock();
1363         return ret;
1364 }
1365
1366 static int
1367 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1368                xfrm_address_t *remote, unsigned short family, u32 mark)
1369 {
1370         int err;
1371         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1372
1373         if (unlikely(afinfo == NULL))
1374                 return -EINVAL;
1375         err = afinfo->get_saddr(net, oif, local, remote, mark);
1376         rcu_read_unlock();
1377         return err;
1378 }
1379
1380 /* Resolve list of templates for the flow, given policy. */
1381
1382 static int
1383 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1384                       struct xfrm_state **xfrm, unsigned short family)
1385 {
1386         struct net *net = xp_net(policy);
1387         int nx;
1388         int i, error;
1389         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1390         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1391         xfrm_address_t tmp;
1392
1393         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1394                 struct xfrm_state *x;
1395                 xfrm_address_t *remote = daddr;
1396                 xfrm_address_t *local  = saddr;
1397                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1398
1399                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1400                     tmpl->mode == XFRM_MODE_BEET) {
1401                         remote = &tmpl->id.daddr;
1402                         local = &tmpl->saddr;
1403                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1404                                 error = xfrm_get_saddr(net, fl->flowi_oif,
1405                                                        &tmp, remote,
1406                                                        tmpl->encap_family, 0);
1407                                 if (error)
1408                                         goto fail;
1409                                 local = &tmp;
1410                         }
1411                 }
1412
1413                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
1414                                     family, policy->if_id);
1415
1416                 if (x && x->km.state == XFRM_STATE_VALID) {
1417                         xfrm[nx++] = x;
1418                         daddr = remote;
1419                         saddr = local;
1420                         continue;
1421                 }
1422                 if (x) {
1423                         error = (x->km.state == XFRM_STATE_ERROR ?
1424                                  -EINVAL : -EAGAIN);
1425                         xfrm_state_put(x);
1426                 } else if (error == -ESRCH) {
1427                         error = -EAGAIN;
1428                 }
1429
1430                 if (!tmpl->optional)
1431                         goto fail;
1432         }
1433         return nx;
1434
1435 fail:
1436         for (nx--; nx >= 0; nx--)
1437                 xfrm_state_put(xfrm[nx]);
1438         return error;
1439 }
1440
1441 static int
1442 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1443                   struct xfrm_state **xfrm, unsigned short family)
1444 {
1445         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1446         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1447         int cnx = 0;
1448         int error;
1449         int ret;
1450         int i;
1451
1452         for (i = 0; i < npols; i++) {
1453                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1454                         error = -ENOBUFS;
1455                         goto fail;
1456                 }
1457
1458                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1459                 if (ret < 0) {
1460                         error = ret;
1461                         goto fail;
1462                 } else
1463                         cnx += ret;
1464         }
1465
1466         /* found states are sorted for outbound processing */
1467         if (npols > 1)
1468                 xfrm_state_sort(xfrm, tpp, cnx, family);
1469
1470         return cnx;
1471
1472  fail:
1473         for (cnx--; cnx >= 0; cnx--)
1474                 xfrm_state_put(tpp[cnx]);
1475         return error;
1476
1477 }
1478
1479 static int xfrm_get_tos(const struct flowi *fl, int family)
1480 {
1481         const struct xfrm_policy_afinfo *afinfo;
1482         int tos;
1483
1484         afinfo = xfrm_policy_get_afinfo(family);
1485         if (!afinfo)
1486                 return 0;
1487
1488         tos = afinfo->get_tos(fl);
1489
1490         rcu_read_unlock();
1491
1492         return tos;
1493 }
1494
1495 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1496 {
1497         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1498         struct dst_ops *dst_ops;
1499         struct xfrm_dst *xdst;
1500
1501         if (!afinfo)
1502                 return ERR_PTR(-EINVAL);
1503
1504         switch (family) {
1505         case AF_INET:
1506                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1507                 break;
1508 #if IS_ENABLED(CONFIG_IPV6)
1509         case AF_INET6:
1510                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1511                 break;
1512 #endif
1513         default:
1514                 BUG();
1515         }
1516         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
1517
1518         if (likely(xdst)) {
1519                 struct dst_entry *dst = &xdst->u.dst;
1520
1521                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1522         } else
1523                 xdst = ERR_PTR(-ENOBUFS);
1524
1525         rcu_read_unlock();
1526
1527         return xdst;
1528 }
1529
1530 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1531                                  int nfheader_len)
1532 {
1533         const struct xfrm_policy_afinfo *afinfo =
1534                 xfrm_policy_get_afinfo(dst->ops->family);
1535         int err;
1536
1537         if (!afinfo)
1538                 return -EINVAL;
1539
1540         err = afinfo->init_path(path, dst, nfheader_len);
1541
1542         rcu_read_unlock();
1543
1544         return err;
1545 }
1546
1547 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1548                                 const struct flowi *fl)
1549 {
1550         const struct xfrm_policy_afinfo *afinfo =
1551                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1552         int err;
1553
1554         if (!afinfo)
1555                 return -EINVAL;
1556
1557         err = afinfo->fill_dst(xdst, dev, fl);
1558
1559         rcu_read_unlock();
1560
1561         return err;
1562 }
1563
1564
1565 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1566  * all the metrics... Shortly, bundle a bundle.
1567  */
1568
1569 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1570                                             struct xfrm_state **xfrm,
1571                                             struct xfrm_dst **bundle,
1572                                             int nx,
1573                                             const struct flowi *fl,
1574                                             struct dst_entry *dst)
1575 {
1576         struct net *net = xp_net(policy);
1577         unsigned long now = jiffies;
1578         struct net_device *dev;
1579         struct xfrm_mode *inner_mode;
1580         struct xfrm_dst *xdst_prev = NULL;
1581         struct xfrm_dst *xdst0 = NULL;
1582         int i = 0;
1583         int err;
1584         int header_len = 0;
1585         int nfheader_len = 0;
1586         int trailer_len = 0;
1587         int tos;
1588         int family = policy->selector.family;
1589         xfrm_address_t saddr, daddr;
1590
1591         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1592
1593         tos = xfrm_get_tos(fl, family);
1594
1595         dst_hold(dst);
1596
1597         for (; i < nx; i++) {
1598                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1599                 struct dst_entry *dst1 = &xdst->u.dst;
1600
1601                 err = PTR_ERR(xdst);
1602                 if (IS_ERR(xdst)) {
1603                         dst_release(dst);
1604                         goto put_states;
1605                 }
1606
1607                 bundle[i] = xdst;
1608                 if (!xdst_prev)
1609                         xdst0 = xdst;
1610                 else
1611                         /* Ref count is taken during xfrm_alloc_dst()
1612                          * No need to do dst_clone() on dst1
1613                          */
1614                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
1615
1616                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1617                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1618                                                         xfrm_af2proto(family));
1619                         if (!inner_mode) {
1620                                 err = -EAFNOSUPPORT;
1621                                 dst_release(dst);
1622                                 goto put_states;
1623                         }
1624                 } else
1625                         inner_mode = xfrm[i]->inner_mode;
1626
1627                 xdst->route = dst;
1628                 dst_copy_metrics(dst1, dst);
1629
1630                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1631                         __u32 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
1632
1633                         family = xfrm[i]->props.family;
1634                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1635                                               &saddr, &daddr, family, mark);
1636                         err = PTR_ERR(dst);
1637                         if (IS_ERR(dst))
1638                                 goto put_states;
1639                 } else
1640                         dst_hold(dst);
1641
1642                 dst1->xfrm = xfrm[i];
1643                 xdst->xfrm_genid = xfrm[i]->genid;
1644
1645                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1646                 dst1->flags |= DST_HOST;
1647                 dst1->lastuse = now;
1648
1649                 dst1->input = dst_discard;
1650                 dst1->output = inner_mode->afinfo->output;
1651
1652                 xdst_prev = xdst;
1653
1654                 header_len += xfrm[i]->props.header_len;
1655                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1656                         nfheader_len += xfrm[i]->props.header_len;
1657                 trailer_len += xfrm[i]->props.trailer_len;
1658         }
1659
1660         xfrm_dst_set_child(xdst_prev, dst);
1661         xdst0->path = dst;
1662
1663         err = -ENODEV;
1664         dev = dst->dev;
1665         if (!dev)
1666                 goto free_dst;
1667
1668         xfrm_init_path(xdst0, dst, nfheader_len);
1669         xfrm_init_pmtu(bundle, nx);
1670
1671         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
1672              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
1673                 err = xfrm_fill_dst(xdst_prev, dev, fl);
1674                 if (err)
1675                         goto free_dst;
1676
1677                 xdst_prev->u.dst.header_len = header_len;
1678                 xdst_prev->u.dst.trailer_len = trailer_len;
1679                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
1680                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
1681         }
1682
1683         return &xdst0->u.dst;
1684
1685 put_states:
1686         for (; i < nx; i++)
1687                 xfrm_state_put(xfrm[i]);
1688 free_dst:
1689         if (xdst0)
1690                 dst_release_immediate(&xdst0->u.dst);
1691
1692         return ERR_PTR(err);
1693 }
1694
1695 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1696                                 struct xfrm_policy **pols,
1697                                 int *num_pols, int *num_xfrms)
1698 {
1699         int i;
1700
1701         if (*num_pols == 0 || !pols[0]) {
1702                 *num_pols = 0;
1703                 *num_xfrms = 0;
1704                 return 0;
1705         }
1706         if (IS_ERR(pols[0]))
1707                 return PTR_ERR(pols[0]);
1708
1709         *num_xfrms = pols[0]->xfrm_nr;
1710
1711 #ifdef CONFIG_XFRM_SUB_POLICY
1712         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1713             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1714                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1715                                                     XFRM_POLICY_TYPE_MAIN,
1716                                                     fl, family,
1717                                                     XFRM_POLICY_OUT,
1718                                                     pols[0]->if_id);
1719                 if (pols[1]) {
1720                         if (IS_ERR(pols[1])) {
1721                                 xfrm_pols_put(pols, *num_pols);
1722                                 return PTR_ERR(pols[1]);
1723                         }
1724                         (*num_pols)++;
1725                         (*num_xfrms) += pols[1]->xfrm_nr;
1726                 }
1727         }
1728 #endif
1729         for (i = 0; i < *num_pols; i++) {
1730                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1731                         *num_xfrms = -1;
1732                         break;
1733                 }
1734         }
1735
1736         return 0;
1737
1738 }
1739
1740 static struct xfrm_dst *
1741 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1742                                const struct flowi *fl, u16 family,
1743                                struct dst_entry *dst_orig)
1744 {
1745         struct net *net = xp_net(pols[0]);
1746         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1747         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
1748         struct xfrm_dst *xdst;
1749         struct dst_entry *dst;
1750         int err;
1751
1752         /* Try to instantiate a bundle */
1753         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1754         if (err <= 0) {
1755                 if (err == 0)
1756                         return NULL;
1757
1758                 if (err != -EAGAIN)
1759                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1760                 return ERR_PTR(err);
1761         }
1762
1763         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
1764         if (IS_ERR(dst)) {
1765                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1766                 return ERR_CAST(dst);
1767         }
1768
1769         xdst = (struct xfrm_dst *)dst;
1770         xdst->num_xfrms = err;
1771         xdst->num_pols = num_pols;
1772         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1773         xdst->policy_genid = atomic_read(&pols[0]->genid);
1774
1775         return xdst;
1776 }
1777
1778 static void xfrm_policy_queue_process(struct timer_list *t)
1779 {
1780         struct sk_buff *skb;
1781         struct sock *sk;
1782         struct dst_entry *dst;
1783         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
1784         struct net *net = xp_net(pol);
1785         struct xfrm_policy_queue *pq = &pol->polq;
1786         struct flowi fl;
1787         struct sk_buff_head list;
1788
1789         spin_lock(&pq->hold_queue.lock);
1790         skb = skb_peek(&pq->hold_queue);
1791         if (!skb) {
1792                 spin_unlock(&pq->hold_queue.lock);
1793                 goto out;
1794         }
1795         dst = skb_dst(skb);
1796         sk = skb->sk;
1797         xfrm_decode_session(skb, &fl, dst->ops->family);
1798         spin_unlock(&pq->hold_queue.lock);
1799
1800         dst_hold(xfrm_dst_path(dst));
1801         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
1802         if (IS_ERR(dst))
1803                 goto purge_queue;
1804
1805         if (dst->flags & DST_XFRM_QUEUE) {
1806                 dst_release(dst);
1807
1808                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1809                         goto purge_queue;
1810
1811                 pq->timeout = pq->timeout << 1;
1812                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1813                         xfrm_pol_hold(pol);
1814         goto out;
1815         }
1816
1817         dst_release(dst);
1818
1819         __skb_queue_head_init(&list);
1820
1821         spin_lock(&pq->hold_queue.lock);
1822         pq->timeout = 0;
1823         skb_queue_splice_init(&pq->hold_queue, &list);
1824         spin_unlock(&pq->hold_queue.lock);
1825
1826         while (!skb_queue_empty(&list)) {
1827                 skb = __skb_dequeue(&list);
1828
1829                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1830                 dst_hold(xfrm_dst_path(skb_dst(skb)));
1831                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
1832                 if (IS_ERR(dst)) {
1833                         kfree_skb(skb);
1834                         continue;
1835                 }
1836
1837                 nf_reset(skb);
1838                 skb_dst_drop(skb);
1839                 skb_dst_set(skb, dst);
1840
1841                 dst_output(net, skb->sk, skb);
1842         }
1843
1844 out:
1845         xfrm_pol_put(pol);
1846         return;
1847
1848 purge_queue:
1849         pq->timeout = 0;
1850         skb_queue_purge(&pq->hold_queue);
1851         xfrm_pol_put(pol);
1852 }
1853
1854 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1855 {
1856         unsigned long sched_next;
1857         struct dst_entry *dst = skb_dst(skb);
1858         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1859         struct xfrm_policy *pol = xdst->pols[0];
1860         struct xfrm_policy_queue *pq = &pol->polq;
1861
1862         if (unlikely(skb_fclone_busy(sk, skb))) {
1863                 kfree_skb(skb);
1864                 return 0;
1865         }
1866
1867         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1868                 kfree_skb(skb);
1869                 return -EAGAIN;
1870         }
1871
1872         skb_dst_force(skb);
1873
1874         spin_lock_bh(&pq->hold_queue.lock);
1875
1876         if (!pq->timeout)
1877                 pq->timeout = XFRM_QUEUE_TMO_MIN;
1878
1879         sched_next = jiffies + pq->timeout;
1880
1881         if (del_timer(&pq->hold_timer)) {
1882                 if (time_before(pq->hold_timer.expires, sched_next))
1883                         sched_next = pq->hold_timer.expires;
1884                 xfrm_pol_put(pol);
1885         }
1886
1887         __skb_queue_tail(&pq->hold_queue, skb);
1888         if (!mod_timer(&pq->hold_timer, sched_next))
1889                 xfrm_pol_hold(pol);
1890
1891         spin_unlock_bh(&pq->hold_queue.lock);
1892
1893         return 0;
1894 }
1895
1896 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1897                                                  struct xfrm_flo *xflo,
1898                                                  const struct flowi *fl,
1899                                                  int num_xfrms,
1900                                                  u16 family)
1901 {
1902         int err;
1903         struct net_device *dev;
1904         struct dst_entry *dst;
1905         struct dst_entry *dst1;
1906         struct xfrm_dst *xdst;
1907
1908         xdst = xfrm_alloc_dst(net, family);
1909         if (IS_ERR(xdst))
1910                 return xdst;
1911
1912         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
1913             net->xfrm.sysctl_larval_drop ||
1914             num_xfrms <= 0)
1915                 return xdst;
1916
1917         dst = xflo->dst_orig;
1918         dst1 = &xdst->u.dst;
1919         dst_hold(dst);
1920         xdst->route = dst;
1921
1922         dst_copy_metrics(dst1, dst);
1923
1924         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1925         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
1926         dst1->lastuse = jiffies;
1927
1928         dst1->input = dst_discard;
1929         dst1->output = xdst_queue_output;
1930
1931         dst_hold(dst);
1932         xfrm_dst_set_child(xdst, dst);
1933         xdst->path = dst;
1934
1935         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
1936
1937         err = -ENODEV;
1938         dev = dst->dev;
1939         if (!dev)
1940                 goto free_dst;
1941
1942         err = xfrm_fill_dst(xdst, dev, fl);
1943         if (err)
1944                 goto free_dst;
1945
1946 out:
1947         return xdst;
1948
1949 free_dst:
1950         dst_release(dst1);
1951         xdst = ERR_PTR(err);
1952         goto out;
1953 }
1954
1955 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
1956                                            const struct flowi *fl,
1957                                            u16 family, u8 dir,
1958                                            struct xfrm_flo *xflo, u32 if_id)
1959 {
1960         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1961         int num_pols = 0, num_xfrms = 0, err;
1962         struct xfrm_dst *xdst;
1963
1964         /* Resolve policies to use if we couldn't get them from
1965          * previous cache entry */
1966         num_pols = 1;
1967         pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
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         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
1978                                               xflo->dst_orig);
1979         if (IS_ERR(xdst)) {
1980                 err = PTR_ERR(xdst);
1981                 if (err == -EREMOTE) {
1982                         xfrm_pols_put(pols, num_pols);
1983                         return NULL;
1984                 }
1985
1986                 if (err != -EAGAIN)
1987                         goto error;
1988                 goto make_dummy_bundle;
1989         } else if (xdst == NULL) {
1990                 num_xfrms = 0;
1991                 goto make_dummy_bundle;
1992         }
1993
1994         return xdst;
1995
1996 make_dummy_bundle:
1997         /* We found policies, but there's no bundles to instantiate:
1998          * either because the policy blocks, has no transformations or
1999          * we could not build template (no xfrm_states).*/
2000         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2001         if (IS_ERR(xdst)) {
2002                 xfrm_pols_put(pols, num_pols);
2003                 return ERR_CAST(xdst);
2004         }
2005         xdst->num_pols = num_pols;
2006         xdst->num_xfrms = num_xfrms;
2007         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2008
2009         return xdst;
2010
2011 inc_error:
2012         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2013 error:
2014         xfrm_pols_put(pols, num_pols);
2015         return ERR_PTR(err);
2016 }
2017
2018 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2019                                         struct dst_entry *dst_orig)
2020 {
2021         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2022         struct dst_entry *ret;
2023
2024         if (!afinfo) {
2025                 dst_release(dst_orig);
2026                 return ERR_PTR(-EINVAL);
2027         } else {
2028                 ret = afinfo->blackhole_route(net, dst_orig);
2029         }
2030         rcu_read_unlock();
2031
2032         return ret;
2033 }
2034
2035 /* Finds/creates a bundle for given flow and if_id
2036  *
2037  * At the moment we eat a raw IP route. Mostly to speed up lookups
2038  * on interfaces with disabled IPsec.
2039  *
2040  * xfrm_lookup uses an if_id of 0 by default, and is provided for
2041  * compatibility
2042  */
2043 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
2044                                         struct dst_entry *dst_orig,
2045                                         const struct flowi *fl,
2046                                         const struct sock *sk,
2047                                         int flags, u32 if_id)
2048 {
2049         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2050         struct xfrm_dst *xdst;
2051         struct dst_entry *dst, *route;
2052         u16 family = dst_orig->ops->family;
2053         u8 dir = XFRM_POLICY_OUT;
2054         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2055
2056         dst = NULL;
2057         xdst = NULL;
2058         route = NULL;
2059
2060         sk = sk_const_to_full_sk(sk);
2061         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2062                 num_pols = 1;
2063                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
2064                                                 if_id);
2065                 err = xfrm_expand_policies(fl, family, pols,
2066                                            &num_pols, &num_xfrms);
2067                 if (err < 0)
2068                         goto dropdst;
2069
2070                 if (num_pols) {
2071                         if (num_xfrms <= 0) {
2072                                 drop_pols = num_pols;
2073                                 goto no_transform;
2074                         }
2075
2076                         xdst = xfrm_resolve_and_create_bundle(
2077                                         pols, num_pols, fl,
2078                                         family, dst_orig);
2079
2080                         if (IS_ERR(xdst)) {
2081                                 xfrm_pols_put(pols, num_pols);
2082                                 err = PTR_ERR(xdst);
2083                                 if (err == -EREMOTE)
2084                                         goto nopol;
2085
2086                                 goto dropdst;
2087                         } else if (xdst == NULL) {
2088                                 num_xfrms = 0;
2089                                 drop_pols = num_pols;
2090                                 goto no_transform;
2091                         }
2092
2093                         route = xdst->route;
2094                 }
2095         }
2096
2097         if (xdst == NULL) {
2098                 struct xfrm_flo xflo;
2099
2100                 xflo.dst_orig = dst_orig;
2101                 xflo.flags = flags;
2102
2103                 /* To accelerate a bit...  */
2104                 if ((dst_orig->flags & DST_NOXFRM) ||
2105                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2106                         goto nopol;
2107
2108                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
2109                 if (xdst == NULL)
2110                         goto nopol;
2111                 if (IS_ERR(xdst)) {
2112                         err = PTR_ERR(xdst);
2113                         goto dropdst;
2114                 }
2115
2116                 num_pols = xdst->num_pols;
2117                 num_xfrms = xdst->num_xfrms;
2118                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2119                 route = xdst->route;
2120         }
2121
2122         dst = &xdst->u.dst;
2123         if (route == NULL && num_xfrms > 0) {
2124                 /* The only case when xfrm_bundle_lookup() returns a
2125                  * bundle with null route, is when the template could
2126                  * not be resolved. It means policies are there, but
2127                  * bundle could not be created, since we don't yet
2128                  * have the xfrm_state's. We need to wait for KM to
2129                  * negotiate new SA's or bail out with error.*/
2130                 if (net->xfrm.sysctl_larval_drop) {
2131                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2132                         err = -EREMOTE;
2133                         goto error;
2134                 }
2135
2136                 err = -EAGAIN;
2137
2138                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2139                 goto error;
2140         }
2141
2142 no_transform:
2143         if (num_pols == 0)
2144                 goto nopol;
2145
2146         if ((flags & XFRM_LOOKUP_ICMP) &&
2147             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2148                 err = -ENOENT;
2149                 goto error;
2150         }
2151
2152         for (i = 0; i < num_pols; i++)
2153                 pols[i]->curlft.use_time = ktime_get_real_seconds();
2154
2155         if (num_xfrms < 0) {
2156                 /* Prohibit the flow */
2157                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2158                 err = -EPERM;
2159                 goto error;
2160         } else if (num_xfrms > 0) {
2161                 /* Flow transformed */
2162                 dst_release(dst_orig);
2163         } else {
2164                 /* Flow passes untransformed */
2165                 dst_release(dst);
2166                 dst = dst_orig;
2167         }
2168 ok:
2169         xfrm_pols_put(pols, drop_pols);
2170         if (dst && dst->xfrm &&
2171             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2172                 dst->flags |= DST_XFRM_TUNNEL;
2173         return dst;
2174
2175 nopol:
2176         if (!(flags & XFRM_LOOKUP_ICMP)) {
2177                 dst = dst_orig;
2178                 goto ok;
2179         }
2180         err = -ENOENT;
2181 error:
2182         dst_release(dst);
2183 dropdst:
2184         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2185                 dst_release(dst_orig);
2186         xfrm_pols_put(pols, drop_pols);
2187         return ERR_PTR(err);
2188 }
2189 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
2190
2191 /* Main function: finds/creates a bundle for given flow.
2192  *
2193  * At the moment we eat a raw IP route. Mostly to speed up lookups
2194  * on interfaces with disabled IPsec.
2195  */
2196 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2197                               const struct flowi *fl, const struct sock *sk,
2198                               int flags)
2199 {
2200         return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
2201 }
2202 EXPORT_SYMBOL(xfrm_lookup);
2203
2204 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2205  * Otherwise we may send out blackholed packets.
2206  */
2207 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2208                                     const struct flowi *fl,
2209                                     const struct sock *sk, int flags)
2210 {
2211         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2212                                             flags | XFRM_LOOKUP_QUEUE |
2213                                             XFRM_LOOKUP_KEEP_DST_REF);
2214
2215         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2216                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2217
2218         if (IS_ERR(dst))
2219                 dst_release(dst_orig);
2220
2221         return dst;
2222 }
2223 EXPORT_SYMBOL(xfrm_lookup_route);
2224
2225 static inline int
2226 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2227 {
2228         struct xfrm_state *x;
2229
2230         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2231                 return 0;
2232         x = skb->sp->xvec[idx];
2233         if (!x->type->reject)
2234                 return 0;
2235         return x->type->reject(x, skb, fl);
2236 }
2237
2238 /* When skb is transformed back to its "native" form, we have to
2239  * check policy restrictions. At the moment we make this in maximally
2240  * stupid way. Shame on me. :-) Of course, connected sockets must
2241  * have policy cached at them.
2242  */
2243
2244 static inline int
2245 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2246               unsigned short family)
2247 {
2248         if (xfrm_state_kern(x))
2249                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2250         return  x->id.proto == tmpl->id.proto &&
2251                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2252                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2253                 x->props.mode == tmpl->mode &&
2254                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2255                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2256                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2257                   xfrm_state_addr_cmp(tmpl, x, family));
2258 }
2259
2260 /*
2261  * 0 or more than 0 is returned when validation is succeeded (either bypass
2262  * because of optional transport mode, or next index of the mathced secpath
2263  * state with the template.
2264  * -1 is returned when no matching template is found.
2265  * Otherwise "-2 - errored_index" is returned.
2266  */
2267 static inline int
2268 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2269                unsigned short family)
2270 {
2271         int idx = start;
2272
2273         if (tmpl->optional) {
2274                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2275                         return start;
2276         } else
2277                 start = -1;
2278         for (; idx < sp->len; idx++) {
2279                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2280                         return ++idx;
2281                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2282                         if (start == -1)
2283                                 start = -2-idx;
2284                         break;
2285                 }
2286         }
2287         return start;
2288 }
2289
2290 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2291                           unsigned int family, int reverse)
2292 {
2293         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2294         int err;
2295
2296         if (unlikely(afinfo == NULL))
2297                 return -EAFNOSUPPORT;
2298
2299         afinfo->decode_session(skb, fl, reverse);
2300
2301         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2302         rcu_read_unlock();
2303         return err;
2304 }
2305 EXPORT_SYMBOL(__xfrm_decode_session);
2306
2307 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2308 {
2309         for (; k < sp->len; k++) {
2310                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2311                         *idxp = k;
2312                         return 1;
2313                 }
2314         }
2315
2316         return 0;
2317 }
2318
2319 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2320                         unsigned short family)
2321 {
2322         struct net *net = dev_net(skb->dev);
2323         struct xfrm_policy *pol;
2324         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2325         int npols = 0;
2326         int xfrm_nr;
2327         int pi;
2328         int reverse;
2329         struct flowi fl;
2330         int xerr_idx = -1;
2331         const struct xfrm_if_cb *ifcb;
2332         struct xfrm_if *xi;
2333         u32 if_id = 0;
2334
2335         rcu_read_lock();
2336         ifcb = xfrm_if_get_cb();
2337
2338         if (ifcb) {
2339                 xi = ifcb->decode_session(skb);
2340                 if (xi)
2341                         if_id = xi->p.if_id;
2342         }
2343         rcu_read_unlock();
2344
2345         reverse = dir & ~XFRM_POLICY_MASK;
2346         dir &= XFRM_POLICY_MASK;
2347
2348         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2349                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2350                 return 0;
2351         }
2352
2353         nf_nat_decode_session(skb, &fl, family);
2354
2355         /* First, check used SA against their selectors. */
2356         if (skb->sp) {
2357                 int i;
2358
2359                 for (i = skb->sp->len-1; i >= 0; i--) {
2360                         struct xfrm_state *x = skb->sp->xvec[i];
2361                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2362                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2363                                 return 0;
2364                         }
2365                 }
2366         }
2367
2368         pol = NULL;
2369         sk = sk_to_full_sk(sk);
2370         if (sk && sk->sk_policy[dir]) {
2371                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
2372                 if (IS_ERR(pol)) {
2373                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2374                         return 0;
2375                 }
2376         }
2377
2378         if (!pol)
2379                 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
2380
2381         if (IS_ERR(pol)) {
2382                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2383                 return 0;
2384         }
2385
2386         if (!pol) {
2387                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2388                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2389                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2390                         return 0;
2391                 }
2392                 return 1;
2393         }
2394
2395         pol->curlft.use_time = ktime_get_real_seconds();
2396
2397         pols[0] = pol;
2398         npols++;
2399 #ifdef CONFIG_XFRM_SUB_POLICY
2400         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2401                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2402                                                     &fl, family,
2403                                                     XFRM_POLICY_IN, if_id);
2404                 if (pols[1]) {
2405                         if (IS_ERR(pols[1])) {
2406                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2407                                 return 0;
2408                         }
2409                         pols[1]->curlft.use_time = ktime_get_real_seconds();
2410                         npols++;
2411                 }
2412         }
2413 #endif
2414
2415         if (pol->action == XFRM_POLICY_ALLOW) {
2416                 struct sec_path *sp;
2417                 static struct sec_path dummy;
2418                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2419                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2420                 struct xfrm_tmpl **tpp = tp;
2421                 int ti = 0;
2422                 int i, k;
2423
2424                 if ((sp = skb->sp) == NULL)
2425                         sp = &dummy;
2426
2427                 for (pi = 0; pi < npols; pi++) {
2428                         if (pols[pi] != pol &&
2429                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2430                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2431                                 goto reject;
2432                         }
2433                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2434                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2435                                 goto reject_error;
2436                         }
2437                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2438                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2439                 }
2440                 xfrm_nr = ti;
2441                 if (npols > 1) {
2442                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2443                         tpp = stp;
2444                 }
2445
2446                 /* For each tunnel xfrm, find the first matching tmpl.
2447                  * For each tmpl before that, find corresponding xfrm.
2448                  * Order is _important_. Later we will implement
2449                  * some barriers, but at the moment barriers
2450                  * are implied between each two transformations.
2451                  */
2452                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2453                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2454                         if (k < 0) {
2455                                 if (k < -1)
2456                                         /* "-2 - errored_index" returned */
2457                                         xerr_idx = -(2+k);
2458                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2459                                 goto reject;
2460                         }
2461                 }
2462
2463                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2464                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2465                         goto reject;
2466                 }
2467
2468                 xfrm_pols_put(pols, npols);
2469                 return 1;
2470         }
2471         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2472
2473 reject:
2474         xfrm_secpath_reject(xerr_idx, skb, &fl);
2475 reject_error:
2476         xfrm_pols_put(pols, npols);
2477         return 0;
2478 }
2479 EXPORT_SYMBOL(__xfrm_policy_check);
2480
2481 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2482 {
2483         struct net *net = dev_net(skb->dev);
2484         struct flowi fl;
2485         struct dst_entry *dst;
2486         int res = 1;
2487
2488         if (xfrm_decode_session(skb, &fl, family) < 0) {
2489                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2490                 return 0;
2491         }
2492
2493         skb_dst_force(skb);
2494         if (!skb_dst(skb)) {
2495                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2496                 return 0;
2497         }
2498
2499         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2500         if (IS_ERR(dst)) {
2501                 res = 0;
2502                 dst = NULL;
2503         }
2504         skb_dst_set(skb, dst);
2505         return res;
2506 }
2507 EXPORT_SYMBOL(__xfrm_route_forward);
2508
2509 /* Optimize later using cookies and generation ids. */
2510
2511 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2512 {
2513         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2514          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2515          * get validated by dst_ops->check on every use.  We do this
2516          * because when a normal route referenced by an XFRM dst is
2517          * obsoleted we do not go looking around for all parent
2518          * referencing XFRM dsts so that we can invalidate them.  It
2519          * is just too much work.  Instead we make the checks here on
2520          * every use.  For example:
2521          *
2522          *      XFRM dst A --> IPv4 dst X
2523          *
2524          * X is the "xdst->route" of A (X is also the "dst->path" of A
2525          * in this example).  If X is marked obsolete, "A" will not
2526          * notice.  That's what we are validating here via the
2527          * stale_bundle() check.
2528          *
2529          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
2530          * be marked on it.
2531          * This will force stale_bundle() to fail on any xdst bundle with
2532          * this dst linked in it.
2533          */
2534         if (dst->obsolete < 0 && !stale_bundle(dst))
2535                 return dst;
2536
2537         return NULL;
2538 }
2539
2540 static int stale_bundle(struct dst_entry *dst)
2541 {
2542         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2543 }
2544
2545 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2546 {
2547         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
2548                 dst->dev = dev_net(dev)->loopback_dev;
2549                 dev_hold(dst->dev);
2550                 dev_put(dev);
2551         }
2552 }
2553 EXPORT_SYMBOL(xfrm_dst_ifdown);
2554
2555 static void xfrm_link_failure(struct sk_buff *skb)
2556 {
2557         /* Impossible. Such dst must be popped before reaches point of failure. */
2558 }
2559
2560 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2561 {
2562         if (dst) {
2563                 if (dst->obsolete) {
2564                         dst_release(dst);
2565                         dst = NULL;
2566                 }
2567         }
2568         return dst;
2569 }
2570
2571 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
2572 {
2573         while (nr--) {
2574                 struct xfrm_dst *xdst = bundle[nr];
2575                 u32 pmtu, route_mtu_cached;
2576                 struct dst_entry *dst;
2577
2578                 dst = &xdst->u.dst;
2579                 pmtu = dst_mtu(xfrm_dst_child(dst));
2580                 xdst->child_mtu_cached = pmtu;
2581
2582                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2583
2584                 route_mtu_cached = dst_mtu(xdst->route);
2585                 xdst->route_mtu_cached = route_mtu_cached;
2586
2587                 if (pmtu > route_mtu_cached)
2588                         pmtu = route_mtu_cached;
2589
2590                 dst_metric_set(dst, RTAX_MTU, pmtu);
2591         }
2592 }
2593
2594 /* Check that the bundle accepts the flow and its components are
2595  * still valid.
2596  */
2597
2598 static int xfrm_bundle_ok(struct xfrm_dst *first)
2599 {
2600         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2601         struct dst_entry *dst = &first->u.dst;
2602         struct xfrm_dst *xdst;
2603         int start_from, nr;
2604         u32 mtu;
2605
2606         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
2607             (dst->dev && !netif_running(dst->dev)))
2608                 return 0;
2609
2610         if (dst->flags & DST_XFRM_QUEUE)
2611                 return 1;
2612
2613         start_from = nr = 0;
2614         do {
2615                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2616
2617                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2618                         return 0;
2619                 if (xdst->xfrm_genid != dst->xfrm->genid)
2620                         return 0;
2621                 if (xdst->num_pols > 0 &&
2622                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2623                         return 0;
2624
2625                 bundle[nr++] = xdst;
2626
2627                 mtu = dst_mtu(xfrm_dst_child(dst));
2628                 if (xdst->child_mtu_cached != mtu) {
2629                         start_from = nr;
2630                         xdst->child_mtu_cached = mtu;
2631                 }
2632
2633                 if (!dst_check(xdst->route, xdst->route_cookie))
2634                         return 0;
2635                 mtu = dst_mtu(xdst->route);
2636                 if (xdst->route_mtu_cached != mtu) {
2637                         start_from = nr;
2638                         xdst->route_mtu_cached = mtu;
2639                 }
2640
2641                 dst = xfrm_dst_child(dst);
2642         } while (dst->xfrm);
2643
2644         if (likely(!start_from))
2645                 return 1;
2646
2647         xdst = bundle[start_from - 1];
2648         mtu = xdst->child_mtu_cached;
2649         while (start_from--) {
2650                 dst = &xdst->u.dst;
2651
2652                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2653                 if (mtu > xdst->route_mtu_cached)
2654                         mtu = xdst->route_mtu_cached;
2655                 dst_metric_set(dst, RTAX_MTU, mtu);
2656                 if (!start_from)
2657                         break;
2658
2659                 xdst = bundle[start_from - 1];
2660                 xdst->child_mtu_cached = mtu;
2661         }
2662
2663         return 1;
2664 }
2665
2666 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2667 {
2668         return dst_metric_advmss(xfrm_dst_path(dst));
2669 }
2670
2671 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2672 {
2673         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2674
2675         return mtu ? : dst_mtu(xfrm_dst_path(dst));
2676 }
2677
2678 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2679                                         const void *daddr)
2680 {
2681         while (dst->xfrm) {
2682                 const struct xfrm_state *xfrm = dst->xfrm;
2683
2684                 dst = xfrm_dst_child(dst);
2685
2686                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2687                         continue;
2688                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2689                         daddr = xfrm->coaddr;
2690                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2691                         daddr = &xfrm->id.daddr;
2692         }
2693         return daddr;
2694 }
2695
2696 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2697                                            struct sk_buff *skb,
2698                                            const void *daddr)
2699 {
2700         const struct dst_entry *path = xfrm_dst_path(dst);
2701
2702         if (!skb)
2703                 daddr = xfrm_get_dst_nexthop(dst, daddr);
2704         return path->ops->neigh_lookup(path, skb, daddr);
2705 }
2706
2707 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2708 {
2709         const struct dst_entry *path = xfrm_dst_path(dst);
2710
2711         daddr = xfrm_get_dst_nexthop(dst, daddr);
2712         path->ops->confirm_neigh(path, daddr);
2713 }
2714
2715 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2716 {
2717         int err = 0;
2718
2719         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2720                 return -EAFNOSUPPORT;
2721
2722         spin_lock(&xfrm_policy_afinfo_lock);
2723         if (unlikely(xfrm_policy_afinfo[family] != NULL))
2724                 err = -EEXIST;
2725         else {
2726                 struct dst_ops *dst_ops = afinfo->dst_ops;
2727                 if (likely(dst_ops->kmem_cachep == NULL))
2728                         dst_ops->kmem_cachep = xfrm_dst_cache;
2729                 if (likely(dst_ops->check == NULL))
2730                         dst_ops->check = xfrm_dst_check;
2731                 if (likely(dst_ops->default_advmss == NULL))
2732                         dst_ops->default_advmss = xfrm_default_advmss;
2733                 if (likely(dst_ops->mtu == NULL))
2734                         dst_ops->mtu = xfrm_mtu;
2735                 if (likely(dst_ops->negative_advice == NULL))
2736                         dst_ops->negative_advice = xfrm_negative_advice;
2737                 if (likely(dst_ops->link_failure == NULL))
2738                         dst_ops->link_failure = xfrm_link_failure;
2739                 if (likely(dst_ops->neigh_lookup == NULL))
2740                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2741                 if (likely(!dst_ops->confirm_neigh))
2742                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
2743                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2744         }
2745         spin_unlock(&xfrm_policy_afinfo_lock);
2746
2747         return err;
2748 }
2749 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2750
2751 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2752 {
2753         struct dst_ops *dst_ops = afinfo->dst_ops;
2754         int i;
2755
2756         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2757                 if (xfrm_policy_afinfo[i] != afinfo)
2758                         continue;
2759                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2760                 break;
2761         }
2762
2763         synchronize_rcu();
2764
2765         dst_ops->kmem_cachep = NULL;
2766         dst_ops->check = NULL;
2767         dst_ops->negative_advice = NULL;
2768         dst_ops->link_failure = NULL;
2769 }
2770 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2771
2772 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
2773 {
2774         spin_lock(&xfrm_if_cb_lock);
2775         rcu_assign_pointer(xfrm_if_cb, ifcb);
2776         spin_unlock(&xfrm_if_cb_lock);
2777 }
2778 EXPORT_SYMBOL(xfrm_if_register_cb);
2779
2780 void xfrm_if_unregister_cb(void)
2781 {
2782         RCU_INIT_POINTER(xfrm_if_cb, NULL);
2783         synchronize_rcu();
2784 }
2785 EXPORT_SYMBOL(xfrm_if_unregister_cb);
2786
2787 #ifdef CONFIG_XFRM_STATISTICS
2788 static int __net_init xfrm_statistics_init(struct net *net)
2789 {
2790         int rv;
2791         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2792         if (!net->mib.xfrm_statistics)
2793                 return -ENOMEM;
2794         rv = xfrm_proc_init(net);
2795         if (rv < 0)
2796                 free_percpu(net->mib.xfrm_statistics);
2797         return rv;
2798 }
2799
2800 static void xfrm_statistics_fini(struct net *net)
2801 {
2802         xfrm_proc_fini(net);
2803         free_percpu(net->mib.xfrm_statistics);
2804 }
2805 #else
2806 static int __net_init xfrm_statistics_init(struct net *net)
2807 {
2808         return 0;
2809 }
2810
2811 static void xfrm_statistics_fini(struct net *net)
2812 {
2813 }
2814 #endif
2815
2816 static int __net_init xfrm_policy_init(struct net *net)
2817 {
2818         unsigned int hmask, sz;
2819         int dir;
2820
2821         if (net_eq(net, &init_net))
2822                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2823                                            sizeof(struct xfrm_dst),
2824                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2825                                            NULL);
2826
2827         hmask = 8 - 1;
2828         sz = (hmask+1) * sizeof(struct hlist_head);
2829
2830         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2831         if (!net->xfrm.policy_byidx)
2832                 goto out_byidx;
2833         net->xfrm.policy_idx_hmask = hmask;
2834
2835         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2836                 struct xfrm_policy_hash *htab;
2837
2838                 net->xfrm.policy_count[dir] = 0;
2839                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2840                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2841
2842                 htab = &net->xfrm.policy_bydst[dir];
2843                 htab->table = xfrm_hash_alloc(sz);
2844                 if (!htab->table)
2845                         goto out_bydst;
2846                 htab->hmask = hmask;
2847                 htab->dbits4 = 32;
2848                 htab->sbits4 = 32;
2849                 htab->dbits6 = 128;
2850                 htab->sbits6 = 128;
2851         }
2852         net->xfrm.policy_hthresh.lbits4 = 32;
2853         net->xfrm.policy_hthresh.rbits4 = 32;
2854         net->xfrm.policy_hthresh.lbits6 = 128;
2855         net->xfrm.policy_hthresh.rbits6 = 128;
2856
2857         seqlock_init(&net->xfrm.policy_hthresh.lock);
2858
2859         INIT_LIST_HEAD(&net->xfrm.policy_all);
2860         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2861         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2862         return 0;
2863
2864 out_bydst:
2865         for (dir--; dir >= 0; dir--) {
2866                 struct xfrm_policy_hash *htab;
2867
2868                 htab = &net->xfrm.policy_bydst[dir];
2869                 xfrm_hash_free(htab->table, sz);
2870         }
2871         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2872 out_byidx:
2873         return -ENOMEM;
2874 }
2875
2876 static void xfrm_policy_fini(struct net *net)
2877 {
2878         unsigned int sz;
2879         int dir;
2880
2881         flush_work(&net->xfrm.policy_hash_work);
2882 #ifdef CONFIG_XFRM_SUB_POLICY
2883         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
2884 #endif
2885         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
2886
2887         WARN_ON(!list_empty(&net->xfrm.policy_all));
2888
2889         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2890                 struct xfrm_policy_hash *htab;
2891
2892                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2893
2894                 htab = &net->xfrm.policy_bydst[dir];
2895                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2896                 WARN_ON(!hlist_empty(htab->table));
2897                 xfrm_hash_free(htab->table, sz);
2898         }
2899
2900         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2901         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2902         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2903 }
2904
2905 static int __net_init xfrm_net_init(struct net *net)
2906 {
2907         int rv;
2908
2909         /* Initialize the per-net locks here */
2910         spin_lock_init(&net->xfrm.xfrm_state_lock);
2911         spin_lock_init(&net->xfrm.xfrm_policy_lock);
2912         mutex_init(&net->xfrm.xfrm_cfg_mutex);
2913
2914         rv = xfrm_statistics_init(net);
2915         if (rv < 0)
2916                 goto out_statistics;
2917         rv = xfrm_state_init(net);
2918         if (rv < 0)
2919                 goto out_state;
2920         rv = xfrm_policy_init(net);
2921         if (rv < 0)
2922                 goto out_policy;
2923         rv = xfrm_sysctl_init(net);
2924         if (rv < 0)
2925                 goto out_sysctl;
2926
2927         return 0;
2928
2929 out_sysctl:
2930         xfrm_policy_fini(net);
2931 out_policy:
2932         xfrm_state_fini(net);
2933 out_state:
2934         xfrm_statistics_fini(net);
2935 out_statistics:
2936         return rv;
2937 }
2938
2939 static void __net_exit xfrm_net_exit(struct net *net)
2940 {
2941         xfrm_sysctl_fini(net);
2942         xfrm_policy_fini(net);
2943         xfrm_state_fini(net);
2944         xfrm_statistics_fini(net);
2945 }
2946
2947 static struct pernet_operations __net_initdata xfrm_net_ops = {
2948         .init = xfrm_net_init,
2949         .exit = xfrm_net_exit,
2950 };
2951
2952 void __init xfrm_init(void)
2953 {
2954         register_pernet_subsys(&xfrm_net_ops);
2955         xfrm_dev_init();
2956         seqcount_init(&xfrm_policy_hash_generation);
2957         xfrm_input_init();
2958
2959         RCU_INIT_POINTER(xfrm_if_cb, NULL);
2960         synchronize_rcu();
2961 }
2962
2963 #ifdef CONFIG_AUDITSYSCALL
2964 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2965                                          struct audit_buffer *audit_buf)
2966 {
2967         struct xfrm_sec_ctx *ctx = xp->security;
2968         struct xfrm_selector *sel = &xp->selector;
2969
2970         if (ctx)
2971                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2972                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2973
2974         switch (sel->family) {
2975         case AF_INET:
2976                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2977                 if (sel->prefixlen_s != 32)
2978                         audit_log_format(audit_buf, " src_prefixlen=%d",
2979                                          sel->prefixlen_s);
2980                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2981                 if (sel->prefixlen_d != 32)
2982                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2983                                          sel->prefixlen_d);
2984                 break;
2985         case AF_INET6:
2986                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
2987                 if (sel->prefixlen_s != 128)
2988                         audit_log_format(audit_buf, " src_prefixlen=%d",
2989                                          sel->prefixlen_s);
2990                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
2991                 if (sel->prefixlen_d != 128)
2992                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2993                                          sel->prefixlen_d);
2994                 break;
2995         }
2996 }
2997
2998 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
2999 {
3000         struct audit_buffer *audit_buf;
3001
3002         audit_buf = xfrm_audit_start("SPD-add");
3003         if (audit_buf == NULL)
3004                 return;
3005         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3006         audit_log_format(audit_buf, " res=%u", result);
3007         xfrm_audit_common_policyinfo(xp, audit_buf);
3008         audit_log_end(audit_buf);
3009 }
3010 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3011
3012 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3013                               bool task_valid)
3014 {
3015         struct audit_buffer *audit_buf;
3016
3017         audit_buf = xfrm_audit_start("SPD-delete");
3018         if (audit_buf == NULL)
3019                 return;
3020         xfrm_audit_helper_usrinfo(task_valid, 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_delete);
3026 #endif
3027
3028 #ifdef CONFIG_XFRM_MIGRATE
3029 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3030                                         const struct xfrm_selector *sel_tgt)
3031 {
3032         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3033                 if (sel_tgt->family == sel_cmp->family &&
3034                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3035                                     sel_cmp->family) &&
3036                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3037                                     sel_cmp->family) &&
3038                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3039                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3040                         return true;
3041                 }
3042         } else {
3043                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3044                         return true;
3045                 }
3046         }
3047         return false;
3048 }
3049
3050 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3051                                                     u8 dir, u8 type, struct net *net)
3052 {
3053         struct xfrm_policy *pol, *ret = NULL;
3054         struct hlist_head *chain;
3055         u32 priority = ~0U;
3056
3057         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3058         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3059         hlist_for_each_entry(pol, chain, bydst) {
3060                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3061                     pol->type == type) {
3062                         ret = pol;
3063                         priority = ret->priority;
3064                         break;
3065                 }
3066         }
3067         chain = &net->xfrm.policy_inexact[dir];
3068         hlist_for_each_entry(pol, chain, bydst) {
3069                 if ((pol->priority >= priority) && ret)
3070                         break;
3071
3072                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3073                     pol->type == type) {
3074                         ret = pol;
3075                         break;
3076                 }
3077         }
3078
3079         xfrm_pol_hold(ret);
3080
3081         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3082
3083         return ret;
3084 }
3085
3086 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3087 {
3088         int match = 0;
3089
3090         if (t->mode == m->mode && t->id.proto == m->proto &&
3091             (m->reqid == 0 || t->reqid == m->reqid)) {
3092                 switch (t->mode) {
3093                 case XFRM_MODE_TUNNEL:
3094                 case XFRM_MODE_BEET:
3095                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3096                                             m->old_family) &&
3097                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3098                                             m->old_family)) {
3099                                 match = 1;
3100                         }
3101                         break;
3102                 case XFRM_MODE_TRANSPORT:
3103                         /* in case of transport mode, template does not store
3104                            any IP addresses, hence we just compare mode and
3105                            protocol */
3106                         match = 1;
3107                         break;
3108                 default:
3109                         break;
3110                 }
3111         }
3112         return match;
3113 }
3114
3115 /* update endpoint address(es) of template(s) */
3116 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3117                                struct xfrm_migrate *m, int num_migrate)
3118 {
3119         struct xfrm_migrate *mp;
3120         int i, j, n = 0;
3121
3122         write_lock_bh(&pol->lock);
3123         if (unlikely(pol->walk.dead)) {
3124                 /* target policy has been deleted */
3125                 write_unlock_bh(&pol->lock);
3126                 return -ENOENT;
3127         }
3128
3129         for (i = 0; i < pol->xfrm_nr; i++) {
3130                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3131                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3132                                 continue;
3133                         n++;
3134                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3135                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3136                                 continue;
3137                         /* update endpoints */
3138                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3139                                sizeof(pol->xfrm_vec[i].id.daddr));
3140                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3141                                sizeof(pol->xfrm_vec[i].saddr));
3142                         pol->xfrm_vec[i].encap_family = mp->new_family;
3143                         /* flush bundles */
3144                         atomic_inc(&pol->genid);
3145                 }
3146         }
3147
3148         write_unlock_bh(&pol->lock);
3149
3150         if (!n)
3151                 return -ENODATA;
3152
3153         return 0;
3154 }
3155
3156 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3157 {
3158         int i, j;
3159
3160         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3161                 return -EINVAL;
3162
3163         for (i = 0; i < num_migrate; i++) {
3164                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3165                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3166                         return -EINVAL;
3167
3168                 /* check if there is any duplicated entry */
3169                 for (j = i + 1; j < num_migrate; j++) {
3170                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3171                                     sizeof(m[i].old_daddr)) &&
3172                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3173                                     sizeof(m[i].old_saddr)) &&
3174                             m[i].proto == m[j].proto &&
3175                             m[i].mode == m[j].mode &&
3176                             m[i].reqid == m[j].reqid &&
3177                             m[i].old_family == m[j].old_family)
3178                                 return -EINVAL;
3179                 }
3180         }
3181
3182         return 0;
3183 }
3184
3185 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3186                  struct xfrm_migrate *m, int num_migrate,
3187                  struct xfrm_kmaddress *k, struct net *net,
3188                  struct xfrm_encap_tmpl *encap)
3189 {
3190         int i, err, nx_cur = 0, nx_new = 0;
3191         struct xfrm_policy *pol = NULL;
3192         struct xfrm_state *x, *xc;
3193         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3194         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3195         struct xfrm_migrate *mp;
3196
3197         /* Stage 0 - sanity checks */
3198         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3199                 goto out;
3200
3201         if (dir >= XFRM_POLICY_MAX) {
3202                 err = -EINVAL;
3203                 goto out;
3204         }
3205
3206         /* Stage 1 - find policy */
3207         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3208                 err = -ENOENT;
3209                 goto out;
3210         }
3211
3212         /* Stage 2 - find and update state(s) */
3213         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3214                 if ((x = xfrm_migrate_state_find(mp, net))) {
3215                         x_cur[nx_cur] = x;
3216                         nx_cur++;
3217                         xc = xfrm_state_migrate(x, mp, encap);
3218                         if (xc) {
3219                                 x_new[nx_new] = xc;
3220                                 nx_new++;
3221                         } else {
3222                                 err = -ENODATA;
3223                                 goto restore_state;
3224                         }
3225                 }
3226         }
3227
3228         /* Stage 3 - update policy */
3229         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3230                 goto restore_state;
3231
3232         /* Stage 4 - delete old state(s) */
3233         if (nx_cur) {
3234                 xfrm_states_put(x_cur, nx_cur);
3235                 xfrm_states_delete(x_cur, nx_cur);
3236         }
3237
3238         /* Stage 5 - announce */
3239         km_migrate(sel, dir, type, m, num_migrate, k, encap);
3240
3241         xfrm_pol_put(pol);
3242
3243         return 0;
3244 out:
3245         return err;
3246
3247 restore_state:
3248         if (pol)
3249                 xfrm_pol_put(pol);
3250         if (nx_cur)
3251                 xfrm_states_put(x_cur, nx_cur);
3252         if (nx_new)
3253                 xfrm_states_delete(x_new, nx_new);
3254
3255         return err;
3256 }
3257 EXPORT_SYMBOL(xfrm_migrate);
3258 #endif