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_PER_CPU(struct xfrm_dst *, xfrm_last_dst);
  49 static struct work_struct *xfrm_pcpu_work __read_mostly;
  50 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
  51 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
  52                                                 __read_mostly;
  53
  54 static struct kmem_cache *xfrm_dst_cache __read_mostly;
  55 static __read_mostly seqcount_t xfrm_policy_hash_generation;
  56
  57 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
  58 static int stale_bundle(struct dst_entry *dst);
  59 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
  60 static void xfrm_policy_queue_process(struct timer_list *t);
  61
  62 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
  63 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
  64                                                 int dir);
  65
  66 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
  67 {
  68         return refcount_inc_not_zero(&policy->refcnt);
  69 }
  70
  71 static inline bool
  72 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  73 {
  74         const struct flowi4 *fl4 = &fl->u.ip4;
  75
  76         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
  77                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
  78                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
  79                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
  80                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
  81                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
  82 }
  83
  84 static inline bool
  85 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  86 {
  87         const struct flowi6 *fl6 = &fl->u.ip6;
  88
  89         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
  90                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
  91                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
  92                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
  93                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
  94                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
  95 }
  96
  97 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
  98                          unsigned short family)
  99 {
 100         switch (family) {
 101         case AF_INET:
 102                 return __xfrm4_selector_match(sel, fl);
 103         case AF_INET6:
 104                 return __xfrm6_selector_match(sel, fl);
 105         }
 106         return false;
 107 }
 108
 109 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 110 {
 111         const struct xfrm_policy_afinfo *afinfo;
 112
 113         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 114                 return NULL;
 115         rcu_read_lock();
 116         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 117         if (unlikely(!afinfo))
 118                 rcu_read_unlock();
 119         return afinfo;
 120 }
 121
 122 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 123                                     const xfrm_address_t *saddr,
 124                                     const xfrm_address_t *daddr,
 125                                     int family, u32 mark)
 126 {
 127         const struct xfrm_policy_afinfo *afinfo;
 128         struct dst_entry *dst;
 129
 130         afinfo = xfrm_policy_get_afinfo(family);
 131         if (unlikely(afinfo == NULL))
 132                 return ERR_PTR(-EAFNOSUPPORT);
 133
 134         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 135
 136         rcu_read_unlock();
 137
 138         return dst;
 139 }
 140 EXPORT_SYMBOL(__xfrm_dst_lookup);
 141
 142 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 143                                                 int tos, int oif,
 144                                                 xfrm_address_t *prev_saddr,
 145                                                 xfrm_address_t *prev_daddr,
 146                                                 int family, u32 mark)
 147 {
 148         struct net *net = xs_net(x);
 149         xfrm_address_t *saddr = &x->props.saddr;
 150         xfrm_address_t *daddr = &x->id.daddr;
 151         struct dst_entry *dst;
 152
 153         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 154                 saddr = x->coaddr;
 155                 daddr = prev_daddr;
 156         }
 157         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 158                 saddr = prev_saddr;
 159                 daddr = x->coaddr;
 160         }
 161
 162         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 163
 164         if (!IS_ERR(dst)) {
 165                 if (prev_saddr != saddr)
 166                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 167                 if (prev_daddr != daddr)
 168                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 169         }
 170
 171         return dst;
 172 }
 173
 174 static inline unsigned long make_jiffies(long secs)
 175 {
 176         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 177                 return MAX_SCHEDULE_TIMEOUT-1;
 178         else
 179                 return secs*HZ;
 180 }
 181
 182 static void xfrm_policy_timer(struct timer_list *t)
 183 {
 184         struct xfrm_policy *xp = from_timer(xp, t, timer);
 185         unsigned long now = get_seconds();
 186         long next = LONG_MAX;
 187         int warn = 0;
 188         int dir;
 189
 190         read_lock(&xp->lock);
 191
 192         if (unlikely(xp->walk.dead))
 193                 goto out;
 194
 195         dir = xfrm_policy_id2dir(xp->index);
 196
 197         if (xp->lft.hard_add_expires_seconds) {
 198                 long tmo = xp->lft.hard_add_expires_seconds +
 199                         xp->curlft.add_time - now;
 200                 if (tmo <= 0)
 201                         goto expired;
 202                 if (tmo < next)
 203                         next = tmo;
 204         }
 205         if (xp->lft.hard_use_expires_seconds) {
 206                 long tmo = xp->lft.hard_use_expires_seconds +
 207                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 208                 if (tmo <= 0)
 209                         goto expired;
 210                 if (tmo < next)
 211                         next = tmo;
 212         }
 213         if (xp->lft.soft_add_expires_seconds) {
 214                 long tmo = xp->lft.soft_add_expires_seconds +
 215                         xp->curlft.add_time - now;
 216                 if (tmo <= 0) {
 217                         warn = 1;
 218                         tmo = XFRM_KM_TIMEOUT;
 219                 }
 220                 if (tmo < next)
 221                         next = tmo;
 222         }
 223         if (xp->lft.soft_use_expires_seconds) {
 224                 long tmo = xp->lft.soft_use_expires_seconds +
 225                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 226                 if (tmo <= 0) {
 227                         warn = 1;
 228                         tmo = XFRM_KM_TIMEOUT;
 229                 }
 230                 if (tmo < next)
 231                         next = tmo;
 232         }
 233
 234         if (warn)
 235                 km_policy_expired(xp, dir, 0, 0);
 236         if (next != LONG_MAX &&
 237             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 238                 xfrm_pol_hold(xp);
 239
 240 out:
 241         read_unlock(&xp->lock);
 242         xfrm_pol_put(xp);
 243         return;
 244
 245 expired:
 246         read_unlock(&xp->lock);
 247         if (!xfrm_policy_delete(xp, dir))
 248                 km_policy_expired(xp, dir, 1, 0);
 249         xfrm_pol_put(xp);
 250 }
 251
 252 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 253  * SPD calls.
 254  */
 255
 256 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 257 {
 258         struct xfrm_policy *policy;
 259
 260         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 261
 262         if (policy) {
 263                 write_pnet(&policy->xp_net, net);
 264                 INIT_LIST_HEAD(&policy->walk.all);
 265                 INIT_HLIST_NODE(&policy->bydst);
 266                 INIT_HLIST_NODE(&policy->byidx);
 267                 rwlock_init(&policy->lock);
 268                 refcount_set(&policy->refcnt, 1);
 269                 skb_queue_head_init(&policy->polq.hold_queue);
 270                 timer_setup(&policy->timer, xfrm_policy_timer, 0);
 271                 timer_setup(&policy->polq.hold_timer,
 272                             xfrm_policy_queue_process, 0);
 273         }
 274         return policy;
 275 }
 276 EXPORT_SYMBOL(xfrm_policy_alloc);
 277
 278 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 279 {
 280         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 281
 282         security_xfrm_policy_free(policy->security);
 283         kfree(policy);
 284 }
 285
 286 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 287
 288 void xfrm_policy_destroy(struct xfrm_policy *policy)
 289 {
 290         BUG_ON(!policy->walk.dead);
 291
 292         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 293                 BUG();
 294
 295         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 296 }
 297 EXPORT_SYMBOL(xfrm_policy_destroy);
 298
 299 /* Rule must be locked. Release descendant resources, announce
 300  * entry dead. The rule must be unlinked from lists to the moment.
 301  */
 302
 303 static void xfrm_policy_kill(struct xfrm_policy *policy)
 304 {
 305         policy->walk.dead = 1;
 306
 307         atomic_inc(&policy->genid);
 308
 309         if (del_timer(&policy->polq.hold_timer))
 310                 xfrm_pol_put(policy);
 311         skb_queue_purge(&policy->polq.hold_queue);
 312
 313         if (del_timer(&policy->timer))
 314                 xfrm_pol_put(policy);
 315
 316         xfrm_pol_put(policy);
 317 }
 318
 319 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 320
 321 static inline unsigned int idx_hash(struct net *net, u32 index)
 322 {
 323         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 324 }
 325
 326 /* calculate policy hash thresholds */
 327 static void __get_hash_thresh(struct net *net,
 328                               unsigned short family, int dir,
 329                               u8 *dbits, u8 *sbits)
 330 {
 331         switch (family) {
 332         case AF_INET:
 333                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 334                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 335                 break;
 336
 337         case AF_INET6:
 338                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 339                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 340                 break;
 341
 342         default:
 343                 *dbits = 0;
 344                 *sbits = 0;
 345         }
 346 }
 347
 348 static struct hlist_head *policy_hash_bysel(struct net *net,
 349                                             const struct xfrm_selector *sel,
 350                                             unsigned short family, int dir)
 351 {
 352         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 353         unsigned int hash;
 354         u8 dbits;
 355         u8 sbits;
 356
 357         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 358         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 359
 360         if (hash == hmask + 1)
 361                 return &net->xfrm.policy_inexact[dir];
 362
 363         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 364                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 365 }
 366
 367 static struct hlist_head *policy_hash_direct(struct net *net,
 368                                              const xfrm_address_t *daddr,
 369                                              const xfrm_address_t *saddr,
 370                                              unsigned short family, int dir)
 371 {
 372         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 373         unsigned int hash;
 374         u8 dbits;
 375         u8 sbits;
 376
 377         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 378         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 379
 380         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 381                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 382 }
 383
 384 static void xfrm_dst_hash_transfer(struct net *net,
 385                                    struct hlist_head *list,
 386                                    struct hlist_head *ndsttable,
 387                                    unsigned int nhashmask,
 388                                    int dir)
 389 {
 390         struct hlist_node *tmp, *entry0 = NULL;
 391         struct xfrm_policy *pol;
 392         unsigned int h0 = 0;
 393         u8 dbits;
 394         u8 sbits;
 395
 396 redo:
 397         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 398                 unsigned int h;
 399
 400                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 401                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 402                                 pol->family, nhashmask, dbits, sbits);
 403                 if (!entry0) {
 404                         hlist_del_rcu(&pol->bydst);
 405                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 406                         h0 = h;
 407                 } else {
 408                         if (h != h0)
 409                                 continue;
 410                         hlist_del_rcu(&pol->bydst);
 411                         hlist_add_behind_rcu(&pol->bydst, entry0);
 412                 }
 413                 entry0 = &pol->bydst;
 414         }
 415         if (!hlist_empty(list)) {
 416                 entry0 = NULL;
 417                 goto redo;
 418         }
 419 }
 420
 421 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 422                                    struct hlist_head *nidxtable,
 423                                    unsigned int nhashmask)
 424 {
 425         struct hlist_node *tmp;
 426         struct xfrm_policy *pol;
 427
 428         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 429                 unsigned int h;
 430
 431                 h = __idx_hash(pol->index, nhashmask);
 432                 hlist_add_head(&pol->byidx, nidxtable+h);
 433         }
 434 }
 435
 436 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 437 {
 438         return ((old_hmask + 1) << 1) - 1;
 439 }
 440
 441 static void xfrm_bydst_resize(struct net *net, int dir)
 442 {
 443         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 444         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 445         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 446         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 447         struct hlist_head *odst;
 448         int i;
 449
 450         if (!ndst)
 451                 return;
 452
 453         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 454         write_seqcount_begin(&xfrm_policy_hash_generation);
 455
 456         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 457                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 458
 459         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 460                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 461
 462         for (i = hmask; i >= 0; i--)
 463                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 464
 465         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 466         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 467
 468         write_seqcount_end(&xfrm_policy_hash_generation);
 469         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 470
 471         synchronize_rcu();
 472
 473         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 474 }
 475
 476 static void xfrm_byidx_resize(struct net *net, int total)
 477 {
 478         unsigned int hmask = net->xfrm.policy_idx_hmask;
 479         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 480         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 481         struct hlist_head *oidx = net->xfrm.policy_byidx;
 482         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 483         int i;
 484
 485         if (!nidx)
 486                 return;
 487
 488         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 489
 490         for (i = hmask; i >= 0; i--)
 491                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 492
 493         net->xfrm.policy_byidx = nidx;
 494         net->xfrm.policy_idx_hmask = nhashmask;
 495
 496         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 497
 498         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 499 }
 500
 501 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 502 {
 503         unsigned int cnt = net->xfrm.policy_count[dir];
 504         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 505
 506         if (total)
 507                 *total += cnt;
 508
 509         if ((hmask + 1) < xfrm_policy_hashmax &&
 510             cnt > hmask)
 511                 return 1;
 512
 513         return 0;
 514 }
 515
 516 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 517 {
 518         unsigned int hmask = net->xfrm.policy_idx_hmask;
 519
 520         if ((hmask + 1) < xfrm_policy_hashmax &&
 521             total > hmask)
 522                 return 1;
 523
 524         return 0;
 525 }
 526
 527 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 528 {
 529         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 530         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 531         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 532         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 533         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 534         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 535         si->spdhcnt = net->xfrm.policy_idx_hmask;
 536         si->spdhmcnt = xfrm_policy_hashmax;
 537 }
 538 EXPORT_SYMBOL(xfrm_spd_getinfo);
 539
 540 static DEFINE_MUTEX(hash_resize_mutex);
 541 static void xfrm_hash_resize(struct work_struct *work)
 542 {
 543         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 544         int dir, total;
 545
 546         mutex_lock(&hash_resize_mutex);
 547
 548         total = 0;
 549         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 550                 if (xfrm_bydst_should_resize(net, dir, &total))
 551                         xfrm_bydst_resize(net, dir);
 552         }
 553         if (xfrm_byidx_should_resize(net, total))
 554                 xfrm_byidx_resize(net, total);
 555
 556         mutex_unlock(&hash_resize_mutex);
 557 }
 558
 559 static void xfrm_hash_rebuild(struct work_struct *work)
 560 {
 561         struct net *net = container_of(work, struct net,
 562                                        xfrm.policy_hthresh.work);
 563         unsigned int hmask;
 564         struct xfrm_policy *pol;
 565         struct xfrm_policy *policy;
 566         struct hlist_head *chain;
 567         struct hlist_head *odst;
 568         struct hlist_node *newpos;
 569         int i;
 570         int dir;
 571         unsigned seq;
 572         u8 lbits4, rbits4, lbits6, rbits6;
 573
 574         mutex_lock(&hash_resize_mutex);
 575
 576         /* read selector prefixlen thresholds */
 577         do {
 578                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
 579
 580                 lbits4 = net->xfrm.policy_hthresh.lbits4;
 581                 rbits4 = net->xfrm.policy_hthresh.rbits4;
 582                 lbits6 = net->xfrm.policy_hthresh.lbits6;
 583                 rbits6 = net->xfrm.policy_hthresh.rbits6;
 584         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
 585
 586         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 587
 588         /* reset the bydst and inexact table in all directions */
 589         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 590                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
 591                 hmask = net->xfrm.policy_bydst[dir].hmask;
 592                 odst = net->xfrm.policy_bydst[dir].table;
 593                 for (i = hmask; i >= 0; i--)
 594                         INIT_HLIST_HEAD(odst + i);
 595                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
 596                         /* dir out => dst = remote, src = local */
 597                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
 598                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
 599                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
 600                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
 601                 } else {
 602                         /* dir in/fwd => dst = local, src = remote */
 603                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
 604                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
 605                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
 606                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
 607                 }
 608         }
 609
 610         /* re-insert all policies by order of creation */
 611         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 612                 if (policy->walk.dead ||
 613                     xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
 614                         /* skip socket policies */
 615                         continue;
 616                 }
 617                 newpos = NULL;
 618                 chain = policy_hash_bysel(net, &policy->selector,
 619                                           policy->family,
 620                                           xfrm_policy_id2dir(policy->index));
 621                 hlist_for_each_entry(pol, chain, bydst) {
 622                         if (policy->priority >= pol->priority)
 623                                 newpos = &pol->bydst;
 624                         else
 625                                 break;
 626                 }
 627                 if (newpos)
 628                         hlist_add_behind(&policy->bydst, newpos);
 629                 else
 630                         hlist_add_head(&policy->bydst, chain);
 631         }
 632
 633         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 634
 635         mutex_unlock(&hash_resize_mutex);
 636 }
 637
 638 void xfrm_policy_hash_rebuild(struct net *net)
 639 {
 640         schedule_work(&net->xfrm.policy_hthresh.work);
 641 }
 642 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
 643
 644 /* Generate new index... KAME seems to generate them ordered by cost
 645  * of an absolute inpredictability of ordering of rules. This will not pass. */
 646 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
 647 {
 648         static u32 idx_generator;
 649
 650         for (;;) {
 651                 struct hlist_head *list;
 652                 struct xfrm_policy *p;
 653                 u32 idx;
 654                 int found;
 655
 656                 if (!index) {
 657                         idx = (idx_generator | dir);
 658                         idx_generator += 8;
 659                 } else {
 660                         idx = index;
 661                         index = 0;
 662                 }
 663
 664                 if (idx == 0)
 665                         idx = 8;
 666                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 667                 found = 0;
 668                 hlist_for_each_entry(p, list, byidx) {
 669                         if (p->index == idx) {
 670                                 found = 1;
 671                                 break;
 672                         }
 673                 }
 674                 if (!found)
 675                         return idx;
 676         }
 677 }
 678
 679 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 680 {
 681         u32 *p1 = (u32 *) s1;
 682         u32 *p2 = (u32 *) s2;
 683         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 684         int i;
 685
 686         for (i = 0; i < len; i++) {
 687                 if (p1[i] != p2[i])
 688                         return 1;
 689         }
 690
 691         return 0;
 692 }
 693
 694 static void xfrm_policy_requeue(struct xfrm_policy *old,
 695                                 struct xfrm_policy *new)
 696 {
 697         struct xfrm_policy_queue *pq = &old->polq;
 698         struct sk_buff_head list;
 699
 700         if (skb_queue_empty(&pq->hold_queue))
 701                 return;
 702
 703         __skb_queue_head_init(&list);
 704
 705         spin_lock_bh(&pq->hold_queue.lock);
 706         skb_queue_splice_init(&pq->hold_queue, &list);
 707         if (del_timer(&pq->hold_timer))
 708                 xfrm_pol_put(old);
 709         spin_unlock_bh(&pq->hold_queue.lock);
 710
 711         pq = &new->polq;
 712
 713         spin_lock_bh(&pq->hold_queue.lock);
 714         skb_queue_splice(&list, &pq->hold_queue);
 715         pq->timeout = XFRM_QUEUE_TMO_MIN;
 716         if (!mod_timer(&pq->hold_timer, jiffies))
 717                 xfrm_pol_hold(new);
 718         spin_unlock_bh(&pq->hold_queue.lock);
 719 }
 720
 721 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
 722                                    struct xfrm_policy *pol)
 723 {
 724         u32 mark = policy->mark.v & policy->mark.m;
 725
 726         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
 727                 return true;
 728
 729         if ((mark & pol->mark.m) == pol->mark.v &&
 730             policy->priority == pol->priority)
 731                 return true;
 732
 733         return false;
 734 }
 735
 736 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 737 {
 738         struct net *net = xp_net(policy);
 739         struct xfrm_policy *pol;
 740         struct xfrm_policy *delpol;
 741         struct hlist_head *chain;
 742         struct hlist_node *newpos;
 743
 744         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 745         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 746         delpol = NULL;
 747         newpos = NULL;
 748         hlist_for_each_entry(pol, chain, bydst) {
 749                 if (pol->type == policy->type &&
 750                     !selector_cmp(&pol->selector, &policy->selector) &&
 751                     xfrm_policy_mark_match(policy, pol) &&
 752                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 753                     !WARN_ON(delpol)) {
 754                         if (excl) {
 755                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 756                                 return -EEXIST;
 757                         }
 758                         delpol = pol;
 759                         if (policy->priority > pol->priority)
 760                                 continue;
 761                 } else if (policy->priority >= pol->priority) {
 762                         newpos = &pol->bydst;
 763                         continue;
 764                 }
 765                 if (delpol)
 766                         break;
 767         }
 768         if (newpos)
 769                 hlist_add_behind(&policy->bydst, newpos);
 770         else
 771                 hlist_add_head(&policy->bydst, chain);
 772         __xfrm_policy_link(policy, dir);
 773
 774         /* After previous checking, family can either be AF_INET or AF_INET6 */
 775         if (policy->family == AF_INET)
 776                 rt_genid_bump_ipv4(net);
 777         else
 778                 rt_genid_bump_ipv6(net);
 779
 780         if (delpol) {
 781                 xfrm_policy_requeue(delpol, policy);
 782                 __xfrm_policy_unlink(delpol, dir);
 783         }
 784         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
 785         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 786         policy->curlft.add_time = get_seconds();
 787         policy->curlft.use_time = 0;
 788         if (!mod_timer(&policy->timer, jiffies + HZ))
 789                 xfrm_pol_hold(policy);
 790         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 791
 792         if (delpol)
 793                 xfrm_policy_kill(delpol);
 794         else if (xfrm_bydst_should_resize(net, dir, NULL))
 795                 schedule_work(&net->xfrm.policy_hash_work);
 796
 797         return 0;
 798 }
 799 EXPORT_SYMBOL(xfrm_policy_insert);
 800
 801 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
 802                                           int dir, struct xfrm_selector *sel,
 803                                           struct xfrm_sec_ctx *ctx, int delete,
 804                                           int *err)
 805 {
 806         struct xfrm_policy *pol, *ret;
 807         struct hlist_head *chain;
 808
 809         *err = 0;
 810         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 811         chain = policy_hash_bysel(net, sel, sel->family, dir);
 812         ret = NULL;
 813         hlist_for_each_entry(pol, chain, bydst) {
 814                 if (pol->type == type &&
 815                     (mark & pol->mark.m) == pol->mark.v &&
 816                     !selector_cmp(sel, &pol->selector) &&
 817                     xfrm_sec_ctx_match(ctx, pol->security)) {
 818                         xfrm_pol_hold(pol);
 819                         if (delete) {
 820                                 *err = security_xfrm_policy_delete(
 821                                                                 pol->security);
 822                                 if (*err) {
 823                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 824                                         return pol;
 825                                 }
 826                                 __xfrm_policy_unlink(pol, dir);
 827                         }
 828                         ret = pol;
 829                         break;
 830                 }
 831         }
 832         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 833
 834         if (ret && delete)
 835                 xfrm_policy_kill(ret);
 836         return ret;
 837 }
 838 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 839
 840 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
 841                                      int dir, u32 id, int delete, int *err)
 842 {
 843         struct xfrm_policy *pol, *ret;
 844         struct hlist_head *chain;
 845
 846         *err = -ENOENT;
 847         if (xfrm_policy_id2dir(id) != dir)
 848                 return NULL;
 849
 850         *err = 0;
 851         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 852         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 853         ret = NULL;
 854         hlist_for_each_entry(pol, chain, byidx) {
 855                 if (pol->type == type && pol->index == id &&
 856                     (mark & pol->mark.m) == pol->mark.v) {
 857                         xfrm_pol_hold(pol);
 858                         if (delete) {
 859                                 *err = security_xfrm_policy_delete(
 860                                                                 pol->security);
 861                                 if (*err) {
 862                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 863                                         return pol;
 864                                 }
 865                                 __xfrm_policy_unlink(pol, dir);
 866                         }
 867                         ret = pol;
 868                         break;
 869                 }
 870         }
 871         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 872
 873         if (ret && delete)
 874                 xfrm_policy_kill(ret);
 875         return ret;
 876 }
 877 EXPORT_SYMBOL(xfrm_policy_byid);
 878
 879 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 880 static inline int
 881 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 882 {
 883         int dir, err = 0;
 884
 885         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 886                 struct xfrm_policy *pol;
 887                 int i;
 888
 889                 hlist_for_each_entry(pol,
 890                                      &net->xfrm.policy_inexact[dir], bydst) {
 891                         if (pol->type != type)
 892                                 continue;
 893                         err = security_xfrm_policy_delete(pol->security);
 894                         if (err) {
 895                                 xfrm_audit_policy_delete(pol, 0, task_valid);
 896                                 return err;
 897                         }
 898                 }
 899                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 900                         hlist_for_each_entry(pol,
 901                                              net->xfrm.policy_bydst[dir].table + i,
 902                                              bydst) {
 903                                 if (pol->type != type)
 904                                         continue;
 905                                 err = security_xfrm_policy_delete(
 906                                                                 pol->security);
 907                                 if (err) {
 908                                         xfrm_audit_policy_delete(pol, 0,
 909                                                                  task_valid);
 910                                         return err;
 911                                 }
 912                         }
 913                 }
 914         }
 915         return err;
 916 }
 917 #else
 918 static inline int
 919 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 920 {
 921         return 0;
 922 }
 923 #endif
 924
 925 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
 926 {
 927         int dir, err = 0, cnt = 0;
 928
 929         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 930
 931         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
 932         if (err)
 933                 goto out;
 934
 935         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 936                 struct xfrm_policy *pol;
 937                 int i;
 938
 939         again1:
 940                 hlist_for_each_entry(pol,
 941                                      &net->xfrm.policy_inexact[dir], bydst) {
 942                         if (pol->type != type)
 943                                 continue;
 944                         __xfrm_policy_unlink(pol, dir);
 945                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 946                         cnt++;
 947
 948                         xfrm_audit_policy_delete(pol, 1, task_valid);
 949
 950                         xfrm_policy_kill(pol);
 951
 952                         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 953                         goto again1;
 954                 }
 955
 956                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 957         again2:
 958                         hlist_for_each_entry(pol,
 959                                              net->xfrm.policy_bydst[dir].table + i,
 960                                              bydst) {
 961                                 if (pol->type != type)
 962                                         continue;
 963                                 __xfrm_policy_unlink(pol, dir);
 964                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 965                                 cnt++;
 966
 967                                 xfrm_audit_policy_delete(pol, 1, task_valid);
 968                                 xfrm_policy_kill(pol);
 969
 970                                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 971                                 goto again2;
 972                         }
 973                 }
 974
 975         }
 976         if (!cnt)
 977                 err = -ESRCH;
 978 out:
 979         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 980         return err;
 981 }
 982 EXPORT_SYMBOL(xfrm_policy_flush);
 983
 984 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 985                      int (*func)(struct xfrm_policy *, int, int, void*),
 986                      void *data)
 987 {
 988         struct xfrm_policy *pol;
 989         struct xfrm_policy_walk_entry *x;
 990         int error = 0;
 991
 992         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
 993             walk->type != XFRM_POLICY_TYPE_ANY)
 994                 return -EINVAL;
 995
 996         if (list_empty(&walk->walk.all) && walk->seq != 0)
 997                 return 0;
 998
 999         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1000         if (list_empty(&walk->walk.all))
1001                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1002         else
1003                 x = list_first_entry(&walk->walk.all,
1004                                      struct xfrm_policy_walk_entry, all);
1005
1006         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1007                 if (x->dead)
1008                         continue;
1009                 pol = container_of(x, struct xfrm_policy, walk);
1010                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1011                     walk->type != pol->type)
1012                         continue;
1013                 error = func(pol, xfrm_policy_id2dir(pol->index),
1014                              walk->seq, data);
1015                 if (error) {
1016                         list_move_tail(&walk->walk.all, &x->all);
1017                         goto out;
1018                 }
1019                 walk->seq++;
1020         }
1021         if (walk->seq == 0) {
1022                 error = -ENOENT;
1023                 goto out;
1024         }
1025         list_del_init(&walk->walk.all);
1026 out:
1027         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1028         return error;
1029 }
1030 EXPORT_SYMBOL(xfrm_policy_walk);
1031
1032 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1033 {
1034         INIT_LIST_HEAD(&walk->walk.all);
1035         walk->walk.dead = 1;
1036         walk->type = type;
1037         walk->seq = 0;
1038 }
1039 EXPORT_SYMBOL(xfrm_policy_walk_init);
1040
1041 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1042 {
1043         if (list_empty(&walk->walk.all))
1044                 return;
1045
1046         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1047         list_del(&walk->walk.all);
1048         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1049 }
1050 EXPORT_SYMBOL(xfrm_policy_walk_done);
1051
1052 /*
1053  * Find policy to apply to this flow.
1054  *
1055  * Returns 0 if policy found, else an -errno.
1056  */
1057 static int xfrm_policy_match(const struct xfrm_policy *pol,
1058                              const struct flowi *fl,
1059                              u8 type, u16 family, int dir)
1060 {
1061         const struct xfrm_selector *sel = &pol->selector;
1062         int ret = -ESRCH;
1063         bool match;
1064
1065         if (pol->family != family ||
1066             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1067             pol->type != type)
1068                 return ret;
1069
1070         match = xfrm_selector_match(sel, fl, family);
1071         if (match)
1072                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1073                                                   dir);
1074
1075         return ret;
1076 }
1077
1078 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1079                                                      const struct flowi *fl,
1080                                                      u16 family, u8 dir)
1081 {
1082         int err;
1083         struct xfrm_policy *pol, *ret;
1084         const xfrm_address_t *daddr, *saddr;
1085         struct hlist_head *chain;
1086         unsigned int sequence;
1087         u32 priority;
1088
1089         daddr = xfrm_flowi_daddr(fl, family);
1090         saddr = xfrm_flowi_saddr(fl, family);
1091         if (unlikely(!daddr || !saddr))
1092                 return NULL;
1093
1094         rcu_read_lock();
1095  retry:
1096         do {
1097                 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1098                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1099         } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1100
1101         priority = ~0U;
1102         ret = NULL;
1103         hlist_for_each_entry_rcu(pol, chain, bydst) {
1104                 err = xfrm_policy_match(pol, fl, type, family, dir);
1105                 if (err) {
1106                         if (err == -ESRCH)
1107                                 continue;
1108                         else {
1109                                 ret = ERR_PTR(err);
1110                                 goto fail;
1111                         }
1112                 } else {
1113                         ret = pol;
1114                         priority = ret->priority;
1115                         break;
1116                 }
1117         }
1118         chain = &net->xfrm.policy_inexact[dir];
1119         hlist_for_each_entry_rcu(pol, chain, bydst) {
1120                 if ((pol->priority >= priority) && ret)
1121                         break;
1122
1123                 err = xfrm_policy_match(pol, fl, type, family, dir);
1124                 if (err) {
1125                         if (err == -ESRCH)
1126                                 continue;
1127                         else {
1128                                 ret = ERR_PTR(err);
1129                                 goto fail;
1130                         }
1131                 } else {
1132                         ret = pol;
1133                         break;
1134                 }
1135         }
1136
1137         if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1138                 goto retry;
1139
1140         if (ret && !xfrm_pol_hold_rcu(ret))
1141                 goto retry;
1142 fail:
1143         rcu_read_unlock();
1144
1145         return ret;
1146 }
1147
1148 static struct xfrm_policy *
1149 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1150 {
1151 #ifdef CONFIG_XFRM_SUB_POLICY
1152         struct xfrm_policy *pol;
1153
1154         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1155         if (pol != NULL)
1156                 return pol;
1157 #endif
1158         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1159 }
1160
1161 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1162                                                  const struct flowi *fl, u16 family)
1163 {
1164         struct xfrm_policy *pol;
1165
1166         rcu_read_lock();
1167  again:
1168         pol = rcu_dereference(sk->sk_policy[dir]);
1169         if (pol != NULL) {
1170                 bool match;
1171                 int err = 0;
1172
1173                 if (pol->family != family) {
1174                         pol = NULL;
1175                         goto out;
1176                 }
1177
1178                 match = xfrm_selector_match(&pol->selector, fl, family);
1179                 if (match) {
1180                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1181                                 pol = NULL;
1182                                 goto out;
1183                         }
1184                         err = security_xfrm_policy_lookup(pol->security,
1185                                                       fl->flowi_secid,
1186                                                       dir);
1187                         if (!err) {
1188                                 if (!xfrm_pol_hold_rcu(pol))
1189                                         goto again;
1190                         } else if (err == -ESRCH) {
1191                                 pol = NULL;
1192                         } else {
1193                                 pol = ERR_PTR(err);
1194                         }
1195                 } else
1196                         pol = NULL;
1197         }
1198 out:
1199         rcu_read_unlock();
1200         return pol;
1201 }
1202
1203 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1204 {
1205         struct net *net = xp_net(pol);
1206
1207         list_add(&pol->walk.all, &net->xfrm.policy_all);
1208         net->xfrm.policy_count[dir]++;
1209         xfrm_pol_hold(pol);
1210 }
1211
1212 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1213                                                 int dir)
1214 {
1215         struct net *net = xp_net(pol);
1216
1217         if (list_empty(&pol->walk.all))
1218                 return NULL;
1219
1220         /* Socket policies are not hashed. */
1221         if (!hlist_unhashed(&pol->bydst)) {
1222                 hlist_del_rcu(&pol->bydst);
1223                 hlist_del(&pol->byidx);
1224         }
1225
1226         list_del_init(&pol->walk.all);
1227         net->xfrm.policy_count[dir]--;
1228
1229         return pol;
1230 }
1231
1232 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1233 {
1234         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1235 }
1236
1237 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1238 {
1239         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1240 }
1241
1242 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1243 {
1244         struct net *net = xp_net(pol);
1245
1246         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1247         pol = __xfrm_policy_unlink(pol, dir);
1248         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1249         if (pol) {
1250                 xfrm_policy_kill(pol);
1251                 return 0;
1252         }
1253         return -ENOENT;
1254 }
1255 EXPORT_SYMBOL(xfrm_policy_delete);
1256
1257 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1258 {
1259         struct net *net = sock_net(sk);
1260         struct xfrm_policy *old_pol;
1261
1262 #ifdef CONFIG_XFRM_SUB_POLICY
1263         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1264                 return -EINVAL;
1265 #endif
1266
1267         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1268         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1269                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1270         if (pol) {
1271                 pol->curlft.add_time = get_seconds();
1272                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1273                 xfrm_sk_policy_link(pol, dir);
1274         }
1275         rcu_assign_pointer(sk->sk_policy[dir], pol);
1276         if (old_pol) {
1277                 if (pol)
1278                         xfrm_policy_requeue(old_pol, pol);
1279
1280                 /* Unlinking succeeds always. This is the only function
1281                  * allowed to delete or replace socket policy.
1282                  */
1283                 xfrm_sk_policy_unlink(old_pol, dir);
1284         }
1285         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1286
1287         if (old_pol) {
1288                 xfrm_policy_kill(old_pol);
1289         }
1290         return 0;
1291 }
1292
1293 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1294 {
1295         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1296         struct net *net = xp_net(old);
1297
1298         if (newp) {
1299                 newp->selector = old->selector;
1300                 if (security_xfrm_policy_clone(old->security,
1301                                                &newp->security)) {
1302                         kfree(newp);
1303                         return NULL;  /* ENOMEM */
1304                 }
1305                 newp->lft = old->lft;
1306                 newp->curlft = old->curlft;
1307                 newp->mark = old->mark;
1308                 newp->action = old->action;
1309                 newp->flags = old->flags;
1310                 newp->xfrm_nr = old->xfrm_nr;
1311                 newp->index = old->index;
1312                 newp->type = old->type;
1313                 newp->family = old->family;
1314                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1315                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1316                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1317                 xfrm_sk_policy_link(newp, dir);
1318                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1319                 xfrm_pol_put(newp);
1320         }
1321         return newp;
1322 }
1323
1324 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1325 {
1326         const struct xfrm_policy *p;
1327         struct xfrm_policy *np;
1328         int i, ret = 0;
1329
1330         rcu_read_lock();
1331         for (i = 0; i < 2; i++) {
1332                 p = rcu_dereference(osk->sk_policy[i]);
1333                 if (p) {
1334                         np = clone_policy(p, i);
1335                         if (unlikely(!np)) {
1336                                 ret = -ENOMEM;
1337                                 break;
1338                         }
1339                         rcu_assign_pointer(sk->sk_policy[i], np);
1340                 }
1341         }
1342         rcu_read_unlock();
1343         return ret;
1344 }
1345
1346 static int
1347 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1348                xfrm_address_t *remote, unsigned short family, u32 mark)
1349 {
1350         int err;
1351         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1352
1353         if (unlikely(afinfo == NULL))
1354                 return -EINVAL;
1355         err = afinfo->get_saddr(net, oif, local, remote, mark);
1356         rcu_read_unlock();
1357         return err;
1358 }
1359
1360 /* Resolve list of templates for the flow, given policy. */
1361
1362 static int
1363 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1364                       struct xfrm_state **xfrm, unsigned short family)
1365 {
1366         struct net *net = xp_net(policy);
1367         int nx;
1368         int i, error;
1369         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1370         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1371         xfrm_address_t tmp;
1372
1373         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1374                 struct xfrm_state *x;
1375                 xfrm_address_t *remote = daddr;
1376                 xfrm_address_t *local  = saddr;
1377                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1378
1379                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1380                     tmpl->mode == XFRM_MODE_BEET) {
1381                         remote = &tmpl->id.daddr;
1382                         local = &tmpl->saddr;
1383                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1384                                 error = xfrm_get_saddr(net, fl->flowi_oif,
1385                                                        &tmp, remote,
1386                                                        tmpl->encap_family, 0);
1387                                 if (error)
1388                                         goto fail;
1389                                 local = &tmp;
1390                         }
1391                 }
1392
1393                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1394
1395                 if (x && x->km.state == XFRM_STATE_VALID) {
1396                         xfrm[nx++] = x;
1397                         daddr = remote;
1398                         saddr = local;
1399                         continue;
1400                 }
1401                 if (x) {
1402                         error = (x->km.state == XFRM_STATE_ERROR ?
1403                                  -EINVAL : -EAGAIN);
1404                         xfrm_state_put(x);
1405                 } else if (error == -ESRCH) {
1406                         error = -EAGAIN;
1407                 }
1408
1409                 if (!tmpl->optional)
1410                         goto fail;
1411         }
1412         return nx;
1413
1414 fail:
1415         for (nx--; nx >= 0; nx--)
1416                 xfrm_state_put(xfrm[nx]);
1417         return error;
1418 }
1419
1420 static int
1421 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1422                   struct xfrm_state **xfrm, unsigned short family)
1423 {
1424         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1425         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1426         int cnx = 0;
1427         int error;
1428         int ret;
1429         int i;
1430
1431         for (i = 0; i < npols; i++) {
1432                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1433                         error = -ENOBUFS;
1434                         goto fail;
1435                 }
1436
1437                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1438                 if (ret < 0) {
1439                         error = ret;
1440                         goto fail;
1441                 } else
1442                         cnx += ret;
1443         }
1444
1445         /* found states are sorted for outbound processing */
1446         if (npols > 1)
1447                 xfrm_state_sort(xfrm, tpp, cnx, family);
1448
1449         return cnx;
1450
1451  fail:
1452         for (cnx--; cnx >= 0; cnx--)
1453                 xfrm_state_put(tpp[cnx]);
1454         return error;
1455
1456 }
1457
1458 static int xfrm_get_tos(const struct flowi *fl, int family)
1459 {
1460         const struct xfrm_policy_afinfo *afinfo;
1461         int tos = 0;
1462
1463         afinfo = xfrm_policy_get_afinfo(family);
1464         tos = afinfo ? afinfo->get_tos(fl) : 0;
1465
1466         rcu_read_unlock();
1467
1468         return tos;
1469 }
1470
1471 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1472 {
1473         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1474         struct dst_ops *dst_ops;
1475         struct xfrm_dst *xdst;
1476
1477         if (!afinfo)
1478                 return ERR_PTR(-EINVAL);
1479
1480         switch (family) {
1481         case AF_INET:
1482                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1483                 break;
1484 #if IS_ENABLED(CONFIG_IPV6)
1485         case AF_INET6:
1486                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1487                 break;
1488 #endif
1489         default:
1490                 BUG();
1491         }
1492         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
1493
1494         if (likely(xdst)) {
1495                 struct dst_entry *dst = &xdst->u.dst;
1496
1497                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1498         } else
1499                 xdst = ERR_PTR(-ENOBUFS);
1500
1501         rcu_read_unlock();
1502
1503         return xdst;
1504 }
1505
1506 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1507                                  int nfheader_len)
1508 {
1509         const struct xfrm_policy_afinfo *afinfo =
1510                 xfrm_policy_get_afinfo(dst->ops->family);
1511         int err;
1512
1513         if (!afinfo)
1514                 return -EINVAL;
1515
1516         err = afinfo->init_path(path, dst, nfheader_len);
1517
1518         rcu_read_unlock();
1519
1520         return err;
1521 }
1522
1523 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1524                                 const struct flowi *fl)
1525 {
1526         const struct xfrm_policy_afinfo *afinfo =
1527                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1528         int err;
1529
1530         if (!afinfo)
1531                 return -EINVAL;
1532
1533         err = afinfo->fill_dst(xdst, dev, fl);
1534
1535         rcu_read_unlock();
1536
1537         return err;
1538 }
1539
1540
1541 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1542  * all the metrics... Shortly, bundle a bundle.
1543  */
1544
1545 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1546                                             struct xfrm_state **xfrm,
1547                                             struct xfrm_dst **bundle,
1548                                             int nx,
1549                                             const struct flowi *fl,
1550                                             struct dst_entry *dst)
1551 {
1552         struct net *net = xp_net(policy);
1553         unsigned long now = jiffies;
1554         struct net_device *dev;
1555         struct xfrm_mode *inner_mode;
1556         struct xfrm_dst *xdst_prev = NULL;
1557         struct xfrm_dst *xdst0 = NULL;
1558         int i = 0;
1559         int err;
1560         int header_len = 0;
1561         int nfheader_len = 0;
1562         int trailer_len = 0;
1563         int tos;
1564         int family = policy->selector.family;
1565         xfrm_address_t saddr, daddr;
1566
1567         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1568
1569         tos = xfrm_get_tos(fl, family);
1570
1571         dst_hold(dst);
1572
1573         for (; i < nx; i++) {
1574                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1575                 struct dst_entry *dst1 = &xdst->u.dst;
1576
1577                 err = PTR_ERR(xdst);
1578                 if (IS_ERR(xdst)) {
1579                         dst_release(dst);
1580                         goto put_states;
1581                 }
1582
1583                 bundle[i] = xdst;
1584                 if (!xdst_prev)
1585                         xdst0 = xdst;
1586                 else
1587                         /* Ref count is taken during xfrm_alloc_dst()
1588                          * No need to do dst_clone() on dst1
1589                          */
1590                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
1591
1592                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1593                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1594                                                         xfrm_af2proto(family));
1595                         if (!inner_mode) {
1596                                 err = -EAFNOSUPPORT;
1597                                 dst_release(dst);
1598                                 goto put_states;
1599                         }
1600                 } else
1601                         inner_mode = xfrm[i]->inner_mode;
1602
1603                 xdst->route = dst;
1604                 dst_copy_metrics(dst1, dst);
1605
1606                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1607                         family = xfrm[i]->props.family;
1608                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1609                                               &saddr, &daddr, family,
1610                                               xfrm[i]->props.output_mark);
1611                         err = PTR_ERR(dst);
1612                         if (IS_ERR(dst))
1613                                 goto put_states;
1614                 } else
1615                         dst_hold(dst);
1616
1617                 dst1->xfrm = xfrm[i];
1618                 xdst->xfrm_genid = xfrm[i]->genid;
1619
1620                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1621                 dst1->flags |= DST_HOST;
1622                 dst1->lastuse = now;
1623
1624                 dst1->input = dst_discard;
1625                 dst1->output = inner_mode->afinfo->output;
1626
1627                 xdst_prev = xdst;
1628
1629                 header_len += xfrm[i]->props.header_len;
1630                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1631                         nfheader_len += xfrm[i]->props.header_len;
1632                 trailer_len += xfrm[i]->props.trailer_len;
1633         }
1634
1635         xfrm_dst_set_child(xdst_prev, dst);
1636         xdst0->path = dst;
1637
1638         err = -ENODEV;
1639         dev = dst->dev;
1640         if (!dev)
1641                 goto free_dst;
1642
1643         xfrm_init_path(xdst0, dst, nfheader_len);
1644         xfrm_init_pmtu(bundle, nx);
1645
1646         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
1647              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
1648                 err = xfrm_fill_dst(xdst_prev, dev, fl);
1649                 if (err)
1650                         goto free_dst;
1651
1652                 xdst_prev->u.dst.header_len = header_len;
1653                 xdst_prev->u.dst.trailer_len = trailer_len;
1654                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
1655                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
1656         }
1657
1658 out:
1659         return &xdst0->u.dst;
1660
1661 put_states:
1662         for (; i < nx; i++)
1663                 xfrm_state_put(xfrm[i]);
1664 free_dst:
1665         if (xdst0)
1666                 dst_release_immediate(&xdst0->u.dst);
1667         xdst0 = ERR_PTR(err);
1668         goto out;
1669 }
1670
1671 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1672                                 struct xfrm_policy **pols,
1673                                 int *num_pols, int *num_xfrms)
1674 {
1675         int i;
1676
1677         if (*num_pols == 0 || !pols[0]) {
1678                 *num_pols = 0;
1679                 *num_xfrms = 0;
1680                 return 0;
1681         }
1682         if (IS_ERR(pols[0]))
1683                 return PTR_ERR(pols[0]);
1684
1685         *num_xfrms = pols[0]->xfrm_nr;
1686
1687 #ifdef CONFIG_XFRM_SUB_POLICY
1688         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1689             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1690                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1691                                                     XFRM_POLICY_TYPE_MAIN,
1692                                                     fl, family,
1693                                                     XFRM_POLICY_OUT);
1694                 if (pols[1]) {
1695                         if (IS_ERR(pols[1])) {
1696                                 xfrm_pols_put(pols, *num_pols);
1697                                 return PTR_ERR(pols[1]);
1698                         }
1699                         (*num_pols)++;
1700                         (*num_xfrms) += pols[1]->xfrm_nr;
1701                 }
1702         }
1703 #endif
1704         for (i = 0; i < *num_pols; i++) {
1705                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
1706                         *num_xfrms = -1;
1707                         break;
1708                 }
1709         }
1710
1711         return 0;
1712
1713 }
1714
1715 static void xfrm_last_dst_update(struct xfrm_dst *xdst, struct xfrm_dst *old)
1716 {
1717         this_cpu_write(xfrm_last_dst, xdst);
1718         if (old)
1719                 dst_release(&old->u.dst);
1720 }
1721
1722 static void __xfrm_pcpu_work_fn(void)
1723 {
1724         struct xfrm_dst *old;
1725
1726         old = this_cpu_read(xfrm_last_dst);
1727         if (old && !xfrm_bundle_ok(old))
1728                 xfrm_last_dst_update(NULL, old);
1729 }
1730
1731 static void xfrm_pcpu_work_fn(struct work_struct *work)
1732 {
1733         local_bh_disable();
1734         rcu_read_lock();
1735         __xfrm_pcpu_work_fn();
1736         rcu_read_unlock();
1737         local_bh_enable();
1738 }
1739
1740 void xfrm_policy_cache_flush(void)
1741 {
1742         struct xfrm_dst *old;
1743         bool found = 0;
1744         int cpu;
1745
1746         might_sleep();
1747
1748         local_bh_disable();
1749         rcu_read_lock();
1750         for_each_possible_cpu(cpu) {
1751                 old = per_cpu(xfrm_last_dst, cpu);
1752                 if (old && !xfrm_bundle_ok(old)) {
1753                         if (smp_processor_id() == cpu) {
1754                                 __xfrm_pcpu_work_fn();
1755                                 continue;
1756                         }
1757                         found = true;
1758                         break;
1759                 }
1760         }
1761
1762         rcu_read_unlock();
1763         local_bh_enable();
1764
1765         if (!found)
1766                 return;
1767
1768         get_online_cpus();
1769
1770         for_each_possible_cpu(cpu) {
1771                 bool bundle_release;
1772
1773                 rcu_read_lock();
1774                 old = per_cpu(xfrm_last_dst, cpu);
1775                 bundle_release = old && !xfrm_bundle_ok(old);
1776                 rcu_read_unlock();
1777
1778                 if (!bundle_release)
1779                         continue;
1780
1781                 if (cpu_online(cpu)) {
1782                         schedule_work_on(cpu, &xfrm_pcpu_work[cpu]);
1783                         continue;
1784                 }
1785
1786                 rcu_read_lock();
1787                 old = per_cpu(xfrm_last_dst, cpu);
1788                 if (old && !xfrm_bundle_ok(old)) {
1789                         per_cpu(xfrm_last_dst, cpu) = NULL;
1790                         dst_release(&old->u.dst);
1791                 }
1792                 rcu_read_unlock();
1793         }
1794
1795         put_online_cpus();
1796 }
1797
1798 static bool xfrm_xdst_can_reuse(struct xfrm_dst *xdst,
1799                                 struct xfrm_state * const xfrm[],
1800                                 int num)
1801 {
1802         const struct dst_entry *dst = &xdst->u.dst;
1803         int i;
1804
1805         if (xdst->num_xfrms != num)
1806                 return false;
1807
1808         for (i = 0; i < num; i++) {
1809                 if (!dst || dst->xfrm != xfrm[i])
1810                         return false;
1811                 dst = xfrm_dst_child(dst);
1812         }
1813
1814         return xfrm_bundle_ok(xdst);
1815 }
1816
1817 static struct xfrm_dst *
1818 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1819                                const struct flowi *fl, u16 family,
1820                                struct dst_entry *dst_orig)
1821 {
1822         struct net *net = xp_net(pols[0]);
1823         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1824         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
1825         struct xfrm_dst *xdst, *old;
1826         struct dst_entry *dst;
1827         int err;
1828
1829         /* Try to instantiate a bundle */
1830         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1831         if (err <= 0) {
1832                 if (err != 0 && err != -EAGAIN)
1833                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1834                 return ERR_PTR(err);
1835         }
1836
1837         xdst = this_cpu_read(xfrm_last_dst);
1838         if (xdst &&
1839             xdst->u.dst.dev == dst_orig->dev &&
1840             xdst->num_pols == num_pols &&
1841             memcmp(xdst->pols, pols,
1842                    sizeof(struct xfrm_policy *) * num_pols) == 0 &&
1843             xfrm_xdst_can_reuse(xdst, xfrm, err)) {
1844                 dst_hold(&xdst->u.dst);
1845                 xfrm_pols_put(pols, num_pols);
1846                 while (err > 0)
1847                         xfrm_state_put(xfrm[--err]);
1848                 return xdst;
1849         }
1850
1851         old = xdst;
1852
1853         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
1854         if (IS_ERR(dst)) {
1855                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1856                 return ERR_CAST(dst);
1857         }
1858
1859         xdst = (struct xfrm_dst *)dst;
1860         xdst->num_xfrms = err;
1861         xdst->num_pols = num_pols;
1862         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1863         xdst->policy_genid = atomic_read(&pols[0]->genid);
1864
1865         atomic_set(&xdst->u.dst.__refcnt, 2);
1866         xfrm_last_dst_update(xdst, old);
1867
1868         return xdst;
1869 }
1870
1871 static void xfrm_policy_queue_process(struct timer_list *t)
1872 {
1873         struct sk_buff *skb;
1874         struct sock *sk;
1875         struct dst_entry *dst;
1876         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
1877         struct net *net = xp_net(pol);
1878         struct xfrm_policy_queue *pq = &pol->polq;
1879         struct flowi fl;
1880         struct sk_buff_head list;
1881
1882         spin_lock(&pq->hold_queue.lock);
1883         skb = skb_peek(&pq->hold_queue);
1884         if (!skb) {
1885                 spin_unlock(&pq->hold_queue.lock);
1886                 goto out;
1887         }
1888         dst = skb_dst(skb);
1889         sk = skb->sk;
1890         xfrm_decode_session(skb, &fl, dst->ops->family);
1891         spin_unlock(&pq->hold_queue.lock);
1892
1893         dst_hold(xfrm_dst_path(dst));
1894         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, 0);
1895         if (IS_ERR(dst))
1896                 goto purge_queue;
1897
1898         if (dst->flags & DST_XFRM_QUEUE) {
1899                 dst_release(dst);
1900
1901                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1902                         goto purge_queue;
1903
1904                 pq->timeout = pq->timeout << 1;
1905                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1906                         xfrm_pol_hold(pol);
1907         goto out;
1908         }
1909
1910         dst_release(dst);
1911
1912         __skb_queue_head_init(&list);
1913
1914         spin_lock(&pq->hold_queue.lock);
1915         pq->timeout = 0;
1916         skb_queue_splice_init(&pq->hold_queue, &list);
1917         spin_unlock(&pq->hold_queue.lock);
1918
1919         while (!skb_queue_empty(&list)) {
1920                 skb = __skb_dequeue(&list);
1921
1922                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1923                 dst_hold(xfrm_dst_path(skb_dst(skb)));
1924                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
1925                 if (IS_ERR(dst)) {
1926                         kfree_skb(skb);
1927                         continue;
1928                 }
1929
1930                 nf_reset(skb);
1931                 skb_dst_drop(skb);
1932                 skb_dst_set(skb, dst);
1933
1934                 dst_output(net, skb->sk, skb);
1935         }
1936
1937 out:
1938         xfrm_pol_put(pol);
1939         return;
1940
1941 purge_queue:
1942         pq->timeout = 0;
1943         skb_queue_purge(&pq->hold_queue);
1944         xfrm_pol_put(pol);
1945 }
1946
1947 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1948 {
1949         unsigned long sched_next;
1950         struct dst_entry *dst = skb_dst(skb);
1951         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1952         struct xfrm_policy *pol = xdst->pols[0];
1953         struct xfrm_policy_queue *pq = &pol->polq;
1954
1955         if (unlikely(skb_fclone_busy(sk, skb))) {
1956                 kfree_skb(skb);
1957                 return 0;
1958         }
1959
1960         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1961                 kfree_skb(skb);
1962                 return -EAGAIN;
1963         }
1964
1965         skb_dst_force(skb);
1966
1967         spin_lock_bh(&pq->hold_queue.lock);
1968
1969         if (!pq->timeout)
1970                 pq->timeout = XFRM_QUEUE_TMO_MIN;
1971
1972         sched_next = jiffies + pq->timeout;
1973
1974         if (del_timer(&pq->hold_timer)) {
1975                 if (time_before(pq->hold_timer.expires, sched_next))
1976                         sched_next = pq->hold_timer.expires;
1977                 xfrm_pol_put(pol);
1978         }
1979
1980         __skb_queue_tail(&pq->hold_queue, skb);
1981         if (!mod_timer(&pq->hold_timer, sched_next))
1982                 xfrm_pol_hold(pol);
1983
1984         spin_unlock_bh(&pq->hold_queue.lock);
1985
1986         return 0;
1987 }
1988
1989 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1990                                                  struct xfrm_flo *xflo,
1991                                                  const struct flowi *fl,
1992                                                  int num_xfrms,
1993                                                  u16 family)
1994 {
1995         int err;
1996         struct net_device *dev;
1997         struct dst_entry *dst;
1998         struct dst_entry *dst1;
1999         struct xfrm_dst *xdst;
2000
2001         xdst = xfrm_alloc_dst(net, family);
2002         if (IS_ERR(xdst))
2003                 return xdst;
2004
2005         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2006             net->xfrm.sysctl_larval_drop ||
2007             num_xfrms <= 0)
2008                 return xdst;
2009
2010         dst = xflo->dst_orig;
2011         dst1 = &xdst->u.dst;
2012         dst_hold(dst);
2013         xdst->route = dst;
2014
2015         dst_copy_metrics(dst1, dst);
2016
2017         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2018         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2019         dst1->lastuse = jiffies;
2020
2021         dst1->input = dst_discard;
2022         dst1->output = xdst_queue_output;
2023
2024         dst_hold(dst);
2025         xfrm_dst_set_child(xdst, dst);
2026         xdst->path = dst;
2027
2028         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2029
2030         err = -ENODEV;
2031         dev = dst->dev;
2032         if (!dev)
2033                 goto free_dst;
2034
2035         err = xfrm_fill_dst(xdst, dev, fl);
2036         if (err)
2037                 goto free_dst;
2038
2039 out:
2040         return xdst;
2041
2042 free_dst:
2043         dst_release(dst1);
2044         xdst = ERR_PTR(err);
2045         goto out;
2046 }
2047
2048 static struct xfrm_dst *
2049 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo)
2050 {
2051         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2052         int num_pols = 0, num_xfrms = 0, err;
2053         struct xfrm_dst *xdst;
2054
2055         /* Resolve policies to use if we couldn't get them from
2056          * previous cache entry */
2057         num_pols = 1;
2058         pols[0] = xfrm_policy_lookup(net, fl, family, dir);
2059         err = xfrm_expand_policies(fl, family, pols,
2060                                            &num_pols, &num_xfrms);
2061         if (err < 0)
2062                 goto inc_error;
2063         if (num_pols == 0)
2064                 return NULL;
2065         if (num_xfrms <= 0)
2066                 goto make_dummy_bundle;
2067
2068         local_bh_disable();
2069         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2070                                               xflo->dst_orig);
2071         local_bh_enable();
2072
2073         if (IS_ERR(xdst)) {
2074                 err = PTR_ERR(xdst);
2075                 if (err != -EAGAIN)
2076                         goto error;
2077                 goto make_dummy_bundle;
2078         } else if (xdst == NULL) {
2079                 num_xfrms = 0;
2080                 goto make_dummy_bundle;
2081         }
2082
2083         return xdst;
2084
2085 make_dummy_bundle:
2086         /* We found policies, but there's no bundles to instantiate:
2087          * either because the policy blocks, has no transformations or
2088          * we could not build template (no xfrm_states).*/
2089         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2090         if (IS_ERR(xdst)) {
2091                 xfrm_pols_put(pols, num_pols);
2092                 return ERR_CAST(xdst);
2093         }
2094         xdst->num_pols = num_pols;
2095         xdst->num_xfrms = num_xfrms;
2096         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2097
2098         return xdst;
2099
2100 inc_error:
2101         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2102 error:
2103         xfrm_pols_put(pols, num_pols);
2104         return ERR_PTR(err);
2105 }
2106
2107 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2108                                         struct dst_entry *dst_orig)
2109 {
2110         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2111         struct dst_entry *ret;
2112
2113         if (!afinfo) {
2114                 dst_release(dst_orig);
2115                 return ERR_PTR(-EINVAL);
2116         } else {
2117                 ret = afinfo->blackhole_route(net, dst_orig);
2118         }
2119         rcu_read_unlock();
2120
2121         return ret;
2122 }
2123
2124 /* Main function: finds/creates a bundle for given flow.
2125  *
2126  * At the moment we eat a raw IP route. Mostly to speed up lookups
2127  * on interfaces with disabled IPsec.
2128  */
2129 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2130                               const struct flowi *fl,
2131                               const struct sock *sk, int flags)
2132 {
2133         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2134         struct xfrm_dst *xdst;
2135         struct dst_entry *dst, *route;
2136         u16 family = dst_orig->ops->family;
2137         u8 dir = XFRM_POLICY_OUT;
2138         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2139
2140         dst = NULL;
2141         xdst = NULL;
2142         route = NULL;
2143
2144         sk = sk_const_to_full_sk(sk);
2145         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2146                 num_pols = 1;
2147                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family);
2148                 err = xfrm_expand_policies(fl, family, pols,
2149                                            &num_pols, &num_xfrms);
2150                 if (err < 0)
2151                         goto dropdst;
2152
2153                 if (num_pols) {
2154                         if (num_xfrms <= 0) {
2155                                 drop_pols = num_pols;
2156                                 goto no_transform;
2157                         }
2158
2159                         local_bh_disable();
2160                         xdst = xfrm_resolve_and_create_bundle(
2161                                         pols, num_pols, fl,
2162                                         family, dst_orig);
2163                         local_bh_enable();
2164
2165                         if (IS_ERR(xdst)) {
2166                                 xfrm_pols_put(pols, num_pols);
2167                                 err = PTR_ERR(xdst);
2168                                 goto dropdst;
2169                         } else if (xdst == NULL) {
2170                                 num_xfrms = 0;
2171                                 drop_pols = num_pols;
2172                                 goto no_transform;
2173                         }
2174
2175                         route = xdst->route;
2176                 }
2177         }
2178
2179         if (xdst == NULL) {
2180                 struct xfrm_flo xflo;
2181
2182                 xflo.dst_orig = dst_orig;
2183                 xflo.flags = flags;
2184
2185                 /* To accelerate a bit...  */
2186                 if ((dst_orig->flags & DST_NOXFRM) ||
2187                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2188                         goto nopol;
2189
2190                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo);
2191                 if (xdst == NULL)
2192                         goto nopol;
2193                 if (IS_ERR(xdst)) {
2194                         err = PTR_ERR(xdst);
2195                         goto dropdst;
2196                 }
2197
2198                 num_pols = xdst->num_pols;
2199                 num_xfrms = xdst->num_xfrms;
2200                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2201                 route = xdst->route;
2202         }
2203
2204         dst = &xdst->u.dst;
2205         if (route == NULL && num_xfrms > 0) {
2206                 /* The only case when xfrm_bundle_lookup() returns a
2207                  * bundle with null route, is when the template could
2208                  * not be resolved. It means policies are there, but
2209                  * bundle could not be created, since we don't yet
2210                  * have the xfrm_state's. We need to wait for KM to
2211                  * negotiate new SA's or bail out with error.*/
2212                 if (net->xfrm.sysctl_larval_drop) {
2213                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2214                         err = -EREMOTE;
2215                         goto error;
2216                 }
2217
2218                 err = -EAGAIN;
2219
2220                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2221                 goto error;
2222         }
2223
2224 no_transform:
2225         if (num_pols == 0)
2226                 goto nopol;
2227
2228         if ((flags & XFRM_LOOKUP_ICMP) &&
2229             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2230                 err = -ENOENT;
2231                 goto error;
2232         }
2233
2234         for (i = 0; i < num_pols; i++)
2235                 pols[i]->curlft.use_time = get_seconds();
2236
2237         if (num_xfrms < 0) {
2238                 /* Prohibit the flow */
2239                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2240                 err = -EPERM;
2241                 goto error;
2242         } else if (num_xfrms > 0) {
2243                 /* Flow transformed */
2244                 dst_release(dst_orig);
2245         } else {
2246                 /* Flow passes untransformed */
2247                 dst_release(dst);
2248                 dst = dst_orig;
2249         }
2250 ok:
2251         xfrm_pols_put(pols, drop_pols);
2252         if (dst && dst->xfrm &&
2253             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2254                 dst->flags |= DST_XFRM_TUNNEL;
2255         return dst;
2256
2257 nopol:
2258         if (!(flags & XFRM_LOOKUP_ICMP)) {
2259                 dst = dst_orig;
2260                 goto ok;
2261         }
2262         err = -ENOENT;
2263 error:
2264         dst_release(dst);
2265 dropdst:
2266         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2267                 dst_release(dst_orig);
2268         xfrm_pols_put(pols, drop_pols);
2269         return ERR_PTR(err);
2270 }
2271 EXPORT_SYMBOL(xfrm_lookup);
2272
2273 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2274  * Otherwise we may send out blackholed packets.
2275  */
2276 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2277                                     const struct flowi *fl,
2278                                     const struct sock *sk, int flags)
2279 {
2280         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2281                                             flags | XFRM_LOOKUP_QUEUE |
2282                                             XFRM_LOOKUP_KEEP_DST_REF);
2283
2284         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2285                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2286
2287         return dst;
2288 }
2289 EXPORT_SYMBOL(xfrm_lookup_route);
2290
2291 static inline int
2292 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2293 {
2294         struct xfrm_state *x;
2295
2296         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2297                 return 0;
2298         x = skb->sp->xvec[idx];
2299         if (!x->type->reject)
2300                 return 0;
2301         return x->type->reject(x, skb, fl);
2302 }
2303
2304 /* When skb is transformed back to its "native" form, we have to
2305  * check policy restrictions. At the moment we make this in maximally
2306  * stupid way. Shame on me. :-) Of course, connected sockets must
2307  * have policy cached at them.
2308  */
2309
2310 static inline int
2311 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2312               unsigned short family)
2313 {
2314         if (xfrm_state_kern(x))
2315                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2316         return  x->id.proto == tmpl->id.proto &&
2317                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2318                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2319                 x->props.mode == tmpl->mode &&
2320                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2321                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2322                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2323                   xfrm_state_addr_cmp(tmpl, x, family));
2324 }
2325
2326 /*
2327  * 0 or more than 0 is returned when validation is succeeded (either bypass
2328  * because of optional transport mode, or next index of the mathced secpath
2329  * state with the template.
2330  * -1 is returned when no matching template is found.
2331  * Otherwise "-2 - errored_index" is returned.
2332  */
2333 static inline int
2334 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2335                unsigned short family)
2336 {
2337         int idx = start;
2338
2339         if (tmpl->optional) {
2340                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2341                         return start;
2342         } else
2343                 start = -1;
2344         for (; idx < sp->len; idx++) {
2345                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2346                         return ++idx;
2347                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2348                         if (start == -1)
2349                                 start = -2-idx;
2350                         break;
2351                 }
2352         }
2353         return start;
2354 }
2355
2356 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2357                           unsigned int family, int reverse)
2358 {
2359         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2360         int err;
2361
2362         if (unlikely(afinfo == NULL))
2363                 return -EAFNOSUPPORT;
2364
2365         afinfo->decode_session(skb, fl, reverse);
2366         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2367         rcu_read_unlock();
2368         return err;
2369 }
2370 EXPORT_SYMBOL(__xfrm_decode_session);
2371
2372 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2373 {
2374         for (; k < sp->len; k++) {
2375                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2376                         *idxp = k;
2377                         return 1;
2378                 }
2379         }
2380
2381         return 0;
2382 }
2383
2384 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2385                         unsigned short family)
2386 {
2387         struct net *net = dev_net(skb->dev);
2388         struct xfrm_policy *pol;
2389         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2390         int npols = 0;
2391         int xfrm_nr;
2392         int pi;
2393         int reverse;
2394         struct flowi fl;
2395         int xerr_idx = -1;
2396
2397         reverse = dir & ~XFRM_POLICY_MASK;
2398         dir &= XFRM_POLICY_MASK;
2399
2400         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2401                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2402                 return 0;
2403         }
2404
2405         nf_nat_decode_session(skb, &fl, family);
2406
2407         /* First, check used SA against their selectors. */
2408         if (skb->sp) {
2409                 int i;
2410
2411                 for (i = skb->sp->len-1; i >= 0; i--) {
2412                         struct xfrm_state *x = skb->sp->xvec[i];
2413                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2414                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2415                                 return 0;
2416                         }
2417                 }
2418         }
2419
2420         pol = NULL;
2421         sk = sk_to_full_sk(sk);
2422         if (sk && sk->sk_policy[dir]) {
2423                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family);
2424                 if (IS_ERR(pol)) {
2425                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2426                         return 0;
2427                 }
2428         }
2429
2430         if (!pol)
2431                 pol = xfrm_policy_lookup(net, &fl, family, dir);
2432
2433         if (IS_ERR(pol)) {
2434                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2435                 return 0;
2436         }
2437
2438         if (!pol) {
2439                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2440                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2441                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2442                         return 0;
2443                 }
2444                 return 1;
2445         }
2446
2447         pol->curlft.use_time = get_seconds();
2448
2449         pols[0] = pol;
2450         npols++;
2451 #ifdef CONFIG_XFRM_SUB_POLICY
2452         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2453                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2454                                                     &fl, family,
2455                                                     XFRM_POLICY_IN);
2456                 if (pols[1]) {
2457                         if (IS_ERR(pols[1])) {
2458                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2459                                 return 0;
2460                         }
2461                         pols[1]->curlft.use_time = get_seconds();
2462                         npols++;
2463                 }
2464         }
2465 #endif
2466
2467         if (pol->action == XFRM_POLICY_ALLOW) {
2468                 struct sec_path *sp;
2469                 static struct sec_path dummy;
2470                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2471                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2472                 struct xfrm_tmpl **tpp = tp;
2473                 int ti = 0;
2474                 int i, k;
2475
2476                 if ((sp = skb->sp) == NULL)
2477                         sp = &dummy;
2478
2479                 for (pi = 0; pi < npols; pi++) {
2480                         if (pols[pi] != pol &&
2481                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2482                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2483                                 goto reject;
2484                         }
2485                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2486                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2487                                 goto reject_error;
2488                         }
2489                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2490                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2491                 }
2492                 xfrm_nr = ti;
2493                 if (npols > 1) {
2494                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2495                         tpp = stp;
2496                 }
2497
2498                 /* For each tunnel xfrm, find the first matching tmpl.
2499                  * For each tmpl before that, find corresponding xfrm.
2500                  * Order is _important_. Later we will implement
2501                  * some barriers, but at the moment barriers
2502                  * are implied between each two transformations.
2503                  */
2504                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2505                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2506                         if (k < 0) {
2507                                 if (k < -1)
2508                                         /* "-2 - errored_index" returned */
2509                                         xerr_idx = -(2+k);
2510                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2511                                 goto reject;
2512                         }
2513                 }
2514
2515                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2516                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2517                         goto reject;
2518                 }
2519
2520                 xfrm_pols_put(pols, npols);
2521                 return 1;
2522         }
2523         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2524
2525 reject:
2526         xfrm_secpath_reject(xerr_idx, skb, &fl);
2527 reject_error:
2528         xfrm_pols_put(pols, npols);
2529         return 0;
2530 }
2531 EXPORT_SYMBOL(__xfrm_policy_check);
2532
2533 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2534 {
2535         struct net *net = dev_net(skb->dev);
2536         struct flowi fl;
2537         struct dst_entry *dst;
2538         int res = 1;
2539
2540         if (xfrm_decode_session(skb, &fl, family) < 0) {
2541                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2542                 return 0;
2543         }
2544
2545         skb_dst_force(skb);
2546
2547         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2548         if (IS_ERR(dst)) {
2549                 res = 0;
2550                 dst = NULL;
2551         }
2552         skb_dst_set(skb, dst);
2553         return res;
2554 }
2555 EXPORT_SYMBOL(__xfrm_route_forward);
2556
2557 /* Optimize later using cookies and generation ids. */
2558
2559 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2560 {
2561         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2562          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2563          * get validated by dst_ops->check on every use.  We do this
2564          * because when a normal route referenced by an XFRM dst is
2565          * obsoleted we do not go looking around for all parent
2566          * referencing XFRM dsts so that we can invalidate them.  It
2567          * is just too much work.  Instead we make the checks here on
2568          * every use.  For example:
2569          *
2570          *      XFRM dst A --> IPv4 dst X
2571          *
2572          * X is the "xdst->route" of A (X is also the "dst->path" of A
2573          * in this example).  If X is marked obsolete, "A" will not
2574          * notice.  That's what we are validating here via the
2575          * stale_bundle() check.
2576          *
2577          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
2578          * be marked on it.
2579          * This will force stale_bundle() to fail on any xdst bundle with
2580          * this dst linked in it.
2581          */
2582         if (dst->obsolete < 0 && !stale_bundle(dst))
2583                 return dst;
2584
2585         return NULL;
2586 }
2587
2588 static int stale_bundle(struct dst_entry *dst)
2589 {
2590         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2591 }
2592
2593 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2594 {
2595         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
2596                 dst->dev = dev_net(dev)->loopback_dev;
2597                 dev_hold(dst->dev);
2598                 dev_put(dev);
2599         }
2600 }
2601 EXPORT_SYMBOL(xfrm_dst_ifdown);
2602
2603 static void xfrm_link_failure(struct sk_buff *skb)
2604 {
2605         /* Impossible. Such dst must be popped before reaches point of failure. */
2606 }
2607
2608 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2609 {
2610         if (dst) {
2611                 if (dst->obsolete) {
2612                         dst_release(dst);
2613                         dst = NULL;
2614                 }
2615         }
2616         return dst;
2617 }
2618
2619 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
2620 {
2621         while (nr--) {
2622                 struct xfrm_dst *xdst = bundle[nr];
2623                 u32 pmtu, route_mtu_cached;
2624                 struct dst_entry *dst;
2625
2626                 dst = &xdst->u.dst;
2627                 pmtu = dst_mtu(xfrm_dst_child(dst));
2628                 xdst->child_mtu_cached = pmtu;
2629
2630                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2631
2632                 route_mtu_cached = dst_mtu(xdst->route);
2633                 xdst->route_mtu_cached = route_mtu_cached;
2634
2635                 if (pmtu > route_mtu_cached)
2636                         pmtu = route_mtu_cached;
2637
2638                 dst_metric_set(dst, RTAX_MTU, pmtu);
2639         }
2640 }
2641
2642 /* Check that the bundle accepts the flow and its components are
2643  * still valid.
2644  */
2645
2646 static int xfrm_bundle_ok(struct xfrm_dst *first)
2647 {
2648         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2649         struct dst_entry *dst = &first->u.dst;
2650         struct xfrm_dst *xdst;
2651         int start_from, nr;
2652         u32 mtu;
2653
2654         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
2655             (dst->dev && !netif_running(dst->dev)))
2656                 return 0;
2657
2658         if (dst->flags & DST_XFRM_QUEUE)
2659                 return 1;
2660
2661         start_from = nr = 0;
2662         do {
2663                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2664
2665                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2666                         return 0;
2667                 if (xdst->xfrm_genid != dst->xfrm->genid)
2668                         return 0;
2669                 if (xdst->num_pols > 0 &&
2670                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2671                         return 0;
2672
2673                 bundle[nr++] = xdst;
2674
2675                 mtu = dst_mtu(xfrm_dst_child(dst));
2676                 if (xdst->child_mtu_cached != mtu) {
2677                         start_from = nr;
2678                         xdst->child_mtu_cached = mtu;
2679                 }
2680
2681                 if (!dst_check(xdst->route, xdst->route_cookie))
2682                         return 0;
2683                 mtu = dst_mtu(xdst->route);
2684                 if (xdst->route_mtu_cached != mtu) {
2685                         start_from = nr;
2686                         xdst->route_mtu_cached = mtu;
2687                 }
2688
2689                 dst = xfrm_dst_child(dst);
2690         } while (dst->xfrm);
2691
2692         if (likely(!start_from))
2693                 return 1;
2694
2695         xdst = bundle[start_from - 1];
2696         mtu = xdst->child_mtu_cached;
2697         while (start_from--) {
2698                 dst = &xdst->u.dst;
2699
2700                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2701                 if (mtu > xdst->route_mtu_cached)
2702                         mtu = xdst->route_mtu_cached;
2703                 dst_metric_set(dst, RTAX_MTU, mtu);
2704                 if (!start_from)
2705                         break;
2706
2707                 xdst = bundle[start_from - 1];
2708                 xdst->child_mtu_cached = mtu;
2709         }
2710
2711         return 1;
2712 }
2713
2714 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2715 {
2716         return dst_metric_advmss(xfrm_dst_path(dst));
2717 }
2718
2719 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2720 {
2721         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2722
2723         return mtu ? : dst_mtu(xfrm_dst_path(dst));
2724 }
2725
2726 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2727                                         const void *daddr)
2728 {
2729         while (dst->xfrm) {
2730                 const struct xfrm_state *xfrm = dst->xfrm;
2731
2732                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2733                         continue;
2734                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2735                         daddr = xfrm->coaddr;
2736                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2737                         daddr = &xfrm->id.daddr;
2738
2739                 dst = xfrm_dst_child(dst);
2740         }
2741         return daddr;
2742 }
2743
2744 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2745                                            struct sk_buff *skb,
2746                                            const void *daddr)
2747 {
2748         const struct dst_entry *path = xfrm_dst_path(dst);
2749
2750         if (!skb)
2751                 daddr = xfrm_get_dst_nexthop(dst, daddr);
2752         return path->ops->neigh_lookup(path, skb, daddr);
2753 }
2754
2755 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2756 {
2757         const struct dst_entry *path = xfrm_dst_path(dst);
2758
2759         daddr = xfrm_get_dst_nexthop(dst, daddr);
2760         path->ops->confirm_neigh(path, daddr);
2761 }
2762
2763 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2764 {
2765         int err = 0;
2766
2767         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2768                 return -EAFNOSUPPORT;
2769
2770         spin_lock(&xfrm_policy_afinfo_lock);
2771         if (unlikely(xfrm_policy_afinfo[family] != NULL))
2772                 err = -EEXIST;
2773         else {
2774                 struct dst_ops *dst_ops = afinfo->dst_ops;
2775                 if (likely(dst_ops->kmem_cachep == NULL))
2776                         dst_ops->kmem_cachep = xfrm_dst_cache;
2777                 if (likely(dst_ops->check == NULL))
2778                         dst_ops->check = xfrm_dst_check;
2779                 if (likely(dst_ops->default_advmss == NULL))
2780                         dst_ops->default_advmss = xfrm_default_advmss;
2781                 if (likely(dst_ops->mtu == NULL))
2782                         dst_ops->mtu = xfrm_mtu;
2783                 if (likely(dst_ops->negative_advice == NULL))
2784                         dst_ops->negative_advice = xfrm_negative_advice;
2785                 if (likely(dst_ops->link_failure == NULL))
2786                         dst_ops->link_failure = xfrm_link_failure;
2787                 if (likely(dst_ops->neigh_lookup == NULL))
2788                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2789                 if (likely(!dst_ops->confirm_neigh))
2790                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
2791                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2792         }
2793         spin_unlock(&xfrm_policy_afinfo_lock);
2794
2795         return err;
2796 }
2797 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2798
2799 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2800 {
2801         struct dst_ops *dst_ops = afinfo->dst_ops;
2802         int i;
2803
2804         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2805                 if (xfrm_policy_afinfo[i] != afinfo)
2806                         continue;
2807                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2808                 break;
2809         }
2810
2811         synchronize_rcu();
2812
2813         dst_ops->kmem_cachep = NULL;
2814         dst_ops->check = NULL;
2815         dst_ops->negative_advice = NULL;
2816         dst_ops->link_failure = NULL;
2817 }
2818 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2819
2820 #ifdef CONFIG_XFRM_STATISTICS
2821 static int __net_init xfrm_statistics_init(struct net *net)
2822 {
2823         int rv;
2824         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2825         if (!net->mib.xfrm_statistics)
2826                 return -ENOMEM;
2827         rv = xfrm_proc_init(net);
2828         if (rv < 0)
2829                 free_percpu(net->mib.xfrm_statistics);
2830         return rv;
2831 }
2832
2833 static void xfrm_statistics_fini(struct net *net)
2834 {
2835         xfrm_proc_fini(net);
2836         free_percpu(net->mib.xfrm_statistics);
2837 }
2838 #else
2839 static int __net_init xfrm_statistics_init(struct net *net)
2840 {
2841         return 0;
2842 }
2843
2844 static void xfrm_statistics_fini(struct net *net)
2845 {
2846 }
2847 #endif
2848
2849 static int __net_init xfrm_policy_init(struct net *net)
2850 {
2851         unsigned int hmask, sz;
2852         int dir;
2853
2854         if (net_eq(net, &init_net))
2855                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2856                                            sizeof(struct xfrm_dst),
2857                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2858                                            NULL);
2859
2860         hmask = 8 - 1;
2861         sz = (hmask+1) * sizeof(struct hlist_head);
2862
2863         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2864         if (!net->xfrm.policy_byidx)
2865                 goto out_byidx;
2866         net->xfrm.policy_idx_hmask = hmask;
2867
2868         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2869                 struct xfrm_policy_hash *htab;
2870
2871                 net->xfrm.policy_count[dir] = 0;
2872                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2873                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2874
2875                 htab = &net->xfrm.policy_bydst[dir];
2876                 htab->table = xfrm_hash_alloc(sz);
2877                 if (!htab->table)
2878                         goto out_bydst;
2879                 htab->hmask = hmask;
2880                 htab->dbits4 = 32;
2881                 htab->sbits4 = 32;
2882                 htab->dbits6 = 128;
2883                 htab->sbits6 = 128;
2884         }
2885         net->xfrm.policy_hthresh.lbits4 = 32;
2886         net->xfrm.policy_hthresh.rbits4 = 32;
2887         net->xfrm.policy_hthresh.lbits6 = 128;
2888         net->xfrm.policy_hthresh.rbits6 = 128;
2889
2890         seqlock_init(&net->xfrm.policy_hthresh.lock);
2891
2892         INIT_LIST_HEAD(&net->xfrm.policy_all);
2893         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2894         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2895         if (net_eq(net, &init_net))
2896                 xfrm_dev_init();
2897         return 0;
2898
2899 out_bydst:
2900         for (dir--; dir >= 0; dir--) {
2901                 struct xfrm_policy_hash *htab;
2902
2903                 htab = &net->xfrm.policy_bydst[dir];
2904                 xfrm_hash_free(htab->table, sz);
2905         }
2906         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2907 out_byidx:
2908         return -ENOMEM;
2909 }
2910
2911 static void xfrm_policy_fini(struct net *net)
2912 {
2913         unsigned int sz;
2914         int dir;
2915
2916         flush_work(&net->xfrm.policy_hash_work);
2917 #ifdef CONFIG_XFRM_SUB_POLICY
2918         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
2919 #endif
2920         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
2921
2922         WARN_ON(!list_empty(&net->xfrm.policy_all));
2923
2924         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2925                 struct xfrm_policy_hash *htab;
2926
2927                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2928
2929                 htab = &net->xfrm.policy_bydst[dir];
2930                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2931                 WARN_ON(!hlist_empty(htab->table));
2932                 xfrm_hash_free(htab->table, sz);
2933         }
2934
2935         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2936         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2937         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2938 }
2939
2940 static int __net_init xfrm_net_init(struct net *net)
2941 {
2942         int rv;
2943
2944         /* Initialize the per-net locks here */
2945         spin_lock_init(&net->xfrm.xfrm_state_lock);
2946         spin_lock_init(&net->xfrm.xfrm_policy_lock);
2947         mutex_init(&net->xfrm.xfrm_cfg_mutex);
2948
2949         rv = xfrm_statistics_init(net);
2950         if (rv < 0)
2951                 goto out_statistics;
2952         rv = xfrm_state_init(net);
2953         if (rv < 0)
2954                 goto out_state;
2955         rv = xfrm_policy_init(net);
2956         if (rv < 0)
2957                 goto out_policy;
2958         rv = xfrm_sysctl_init(net);
2959         if (rv < 0)
2960                 goto out_sysctl;
2961
2962         return 0;
2963
2964 out_sysctl:
2965         xfrm_policy_fini(net);
2966 out_policy:
2967         xfrm_state_fini(net);
2968 out_state:
2969         xfrm_statistics_fini(net);
2970 out_statistics:
2971         return rv;
2972 }
2973
2974 static void __net_exit xfrm_net_exit(struct net *net)
2975 {
2976         xfrm_sysctl_fini(net);
2977         xfrm_policy_fini(net);
2978         xfrm_state_fini(net);
2979         xfrm_statistics_fini(net);
2980 }
2981
2982 static struct pernet_operations __net_initdata xfrm_net_ops = {
2983         .init = xfrm_net_init,
2984         .exit = xfrm_net_exit,
2985 };
2986
2987 void __init xfrm_init(void)
2988 {
2989         int i;
2990
2991         xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work),
2992                                        GFP_KERNEL);
2993         BUG_ON(!xfrm_pcpu_work);
2994
2995         for (i = 0; i < NR_CPUS; i++)
2996                 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn);
2997
2998         register_pernet_subsys(&xfrm_net_ops);
2999         seqcount_init(&xfrm_policy_hash_generation);
3000         xfrm_input_init();
3001 }
3002
3003 #ifdef CONFIG_AUDITSYSCALL
3004 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
3005                                          struct audit_buffer *audit_buf)
3006 {
3007         struct xfrm_sec_ctx *ctx = xp->security;
3008         struct xfrm_selector *sel = &xp->selector;
3009
3010         if (ctx)
3011                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
3012                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
3013
3014         switch (sel->family) {
3015         case AF_INET:
3016                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3017                 if (sel->prefixlen_s != 32)
3018                         audit_log_format(audit_buf, " src_prefixlen=%d",
3019                                          sel->prefixlen_s);
3020                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3021                 if (sel->prefixlen_d != 32)
3022                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3023                                          sel->prefixlen_d);
3024                 break;
3025         case AF_INET6:
3026                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3027                 if (sel->prefixlen_s != 128)
3028                         audit_log_format(audit_buf, " src_prefixlen=%d",
3029                                          sel->prefixlen_s);
3030                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3031                 if (sel->prefixlen_d != 128)
3032                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3033                                          sel->prefixlen_d);
3034                 break;
3035         }
3036 }
3037
3038 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3039 {
3040         struct audit_buffer *audit_buf;
3041
3042         audit_buf = xfrm_audit_start("SPD-add");
3043         if (audit_buf == NULL)
3044                 return;
3045         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3046         audit_log_format(audit_buf, " res=%u", result);
3047         xfrm_audit_common_policyinfo(xp, audit_buf);
3048         audit_log_end(audit_buf);
3049 }
3050 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3051
3052 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3053                               bool task_valid)
3054 {
3055         struct audit_buffer *audit_buf;
3056
3057         audit_buf = xfrm_audit_start("SPD-delete");
3058         if (audit_buf == NULL)
3059                 return;
3060         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3061         audit_log_format(audit_buf, " res=%u", result);
3062         xfrm_audit_common_policyinfo(xp, audit_buf);
3063         audit_log_end(audit_buf);
3064 }
3065 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3066 #endif
3067
3068 #ifdef CONFIG_XFRM_MIGRATE
3069 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3070                                         const struct xfrm_selector *sel_tgt)
3071 {
3072         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3073                 if (sel_tgt->family == sel_cmp->family &&
3074                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3075                                     sel_cmp->family) &&
3076                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3077                                     sel_cmp->family) &&
3078                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3079                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3080                         return true;
3081                 }
3082         } else {
3083                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3084                         return true;
3085                 }
3086         }
3087         return false;
3088 }
3089
3090 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3091                                                     u8 dir, u8 type, struct net *net)
3092 {
3093         struct xfrm_policy *pol, *ret = NULL;
3094         struct hlist_head *chain;
3095         u32 priority = ~0U;
3096
3097         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3098         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3099         hlist_for_each_entry(pol, chain, bydst) {
3100                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3101                     pol->type == type) {
3102                         ret = pol;
3103                         priority = ret->priority;
3104                         break;
3105                 }
3106         }
3107         chain = &net->xfrm.policy_inexact[dir];
3108         hlist_for_each_entry(pol, chain, bydst) {
3109                 if ((pol->priority >= priority) && ret)
3110                         break;
3111
3112                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3113                     pol->type == type) {
3114                         ret = pol;
3115                         break;
3116                 }
3117         }
3118
3119         xfrm_pol_hold(ret);
3120
3121         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3122
3123         return ret;
3124 }
3125
3126 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3127 {
3128         int match = 0;
3129
3130         if (t->mode == m->mode && t->id.proto == m->proto &&
3131             (m->reqid == 0 || t->reqid == m->reqid)) {
3132                 switch (t->mode) {
3133                 case XFRM_MODE_TUNNEL:
3134                 case XFRM_MODE_BEET:
3135                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3136                                             m->old_family) &&
3137                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3138                                             m->old_family)) {
3139                                 match = 1;
3140                         }
3141                         break;
3142                 case XFRM_MODE_TRANSPORT:
3143                         /* in case of transport mode, template does not store
3144                            any IP addresses, hence we just compare mode and
3145                            protocol */
3146                         match = 1;
3147                         break;
3148                 default:
3149                         break;
3150                 }
3151         }
3152         return match;
3153 }
3154
3155 /* update endpoint address(es) of template(s) */
3156 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3157                                struct xfrm_migrate *m, int num_migrate)
3158 {
3159         struct xfrm_migrate *mp;
3160         int i, j, n = 0;
3161
3162         write_lock_bh(&pol->lock);
3163         if (unlikely(pol->walk.dead)) {
3164                 /* target policy has been deleted */
3165                 write_unlock_bh(&pol->lock);
3166                 return -ENOENT;
3167         }
3168
3169         for (i = 0; i < pol->xfrm_nr; i++) {
3170                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3171                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3172                                 continue;
3173                         n++;
3174                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3175                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3176                                 continue;
3177                         /* update endpoints */
3178                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3179                                sizeof(pol->xfrm_vec[i].id.daddr));
3180                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3181                                sizeof(pol->xfrm_vec[i].saddr));
3182                         pol->xfrm_vec[i].encap_family = mp->new_family;
3183                         /* flush bundles */
3184                         atomic_inc(&pol->genid);
3185                 }
3186         }
3187
3188         write_unlock_bh(&pol->lock);
3189
3190         if (!n)
3191                 return -ENODATA;
3192
3193         return 0;
3194 }
3195
3196 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3197 {
3198         int i, j;
3199
3200         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3201                 return -EINVAL;
3202
3203         for (i = 0; i < num_migrate; i++) {
3204                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3205                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3206                         return -EINVAL;
3207
3208                 /* check if there is any duplicated entry */
3209                 for (j = i + 1; j < num_migrate; j++) {
3210                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3211                                     sizeof(m[i].old_daddr)) &&
3212                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3213                                     sizeof(m[i].old_saddr)) &&
3214                             m[i].proto == m[j].proto &&
3215                             m[i].mode == m[j].mode &&
3216                             m[i].reqid == m[j].reqid &&
3217                             m[i].old_family == m[j].old_family)
3218                                 return -EINVAL;
3219                 }
3220         }
3221
3222         return 0;
3223 }
3224
3225 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3226                  struct xfrm_migrate *m, int num_migrate,
3227                  struct xfrm_kmaddress *k, struct net *net,
3228                  struct xfrm_encap_tmpl *encap)
3229 {
3230         int i, err, nx_cur = 0, nx_new = 0;
3231         struct xfrm_policy *pol = NULL;
3232         struct xfrm_state *x, *xc;
3233         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3234         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3235         struct xfrm_migrate *mp;
3236
3237         /* Stage 0 - sanity checks */
3238         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3239                 goto out;
3240
3241         if (dir >= XFRM_POLICY_MAX) {
3242                 err = -EINVAL;
3243                 goto out;
3244         }
3245
3246         /* Stage 1 - find policy */
3247         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3248                 err = -ENOENT;
3249                 goto out;
3250         }
3251
3252         /* Stage 2 - find and update state(s) */
3253         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3254                 if ((x = xfrm_migrate_state_find(mp, net))) {
3255                         x_cur[nx_cur] = x;
3256                         nx_cur++;
3257                         xc = xfrm_state_migrate(x, mp, encap);
3258                         if (xc) {
3259                                 x_new[nx_new] = xc;
3260                                 nx_new++;
3261                         } else {
3262                                 err = -ENODATA;
3263                                 goto restore_state;
3264                         }
3265                 }
3266         }
3267
3268         /* Stage 3 - update policy */
3269         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3270                 goto restore_state;
3271
3272         /* Stage 4 - delete old state(s) */
3273         if (nx_cur) {
3274                 xfrm_states_put(x_cur, nx_cur);
3275                 xfrm_states_delete(x_cur, nx_cur);
3276         }
3277
3278         /* Stage 5 - announce */
3279         km_migrate(sel, dir, type, m, num_migrate, k, encap);
3280
3281         xfrm_pol_put(pol);
3282
3283         return 0;
3284 out:
3285         return err;
3286
3287 restore_state:
3288         if (pol)
3289                 xfrm_pol_put(pol);
3290         if (nx_cur)
3291                 xfrm_states_put(x_cur, nx_cur);
3292         if (nx_new)
3293                 xfrm_states_delete(x_new, nx_new);
3294
3295         return err;
3296 }
3297 EXPORT_SYMBOL(xfrm_migrate);
3298 #endif