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 dst_entry *dst);
  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 (xfrm_policy_id2dir(policy->index) >= XFRM_POLICY_MAX) {
 613                         /* skip socket policies */
 614                         continue;
 615                 }
 616                 newpos = NULL;
 617                 chain = policy_hash_bysel(net, &policy->selector,
 618                                           policy->family,
 619                                           xfrm_policy_id2dir(policy->index));
 620                 hlist_for_each_entry(pol, chain, bydst) {
 621                         if (policy->priority >= pol->priority)
 622                                 newpos = &pol->bydst;
 623                         else
 624                                 break;
 625                 }
 626                 if (newpos)
 627                         hlist_add_behind(&policy->bydst, newpos);
 628                 else
 629                         hlist_add_head(&policy->bydst, chain);
 630         }
 631
 632         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 633
 634         mutex_unlock(&hash_resize_mutex);
 635 }
 636
 637 void xfrm_policy_hash_rebuild(struct net *net)
 638 {
 639         schedule_work(&net->xfrm.policy_hthresh.work);
 640 }
 641 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
 642
 643 /* Generate new index... KAME seems to generate them ordered by cost
 644  * of an absolute inpredictability of ordering of rules. This will not pass. */
 645 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
 646 {
 647         static u32 idx_generator;
 648
 649         for (;;) {
 650                 struct hlist_head *list;
 651                 struct xfrm_policy *p;
 652                 u32 idx;
 653                 int found;
 654
 655                 if (!index) {
 656                         idx = (idx_generator | dir);
 657                         idx_generator += 8;
 658                 } else {
 659                         idx = index;
 660                         index = 0;
 661                 }
 662
 663                 if (idx == 0)
 664                         idx = 8;
 665                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 666                 found = 0;
 667                 hlist_for_each_entry(p, list, byidx) {
 668                         if (p->index == idx) {
 669                                 found = 1;
 670                                 break;
 671                         }
 672                 }
 673                 if (!found)
 674                         return idx;
 675         }
 676 }
 677
 678 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 679 {
 680         u32 *p1 = (u32 *) s1;
 681         u32 *p2 = (u32 *) s2;
 682         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 683         int i;
 684
 685         for (i = 0; i < len; i++) {
 686                 if (p1[i] != p2[i])
 687                         return 1;
 688         }
 689
 690         return 0;
 691 }
 692
 693 static void xfrm_policy_requeue(struct xfrm_policy *old,
 694                                 struct xfrm_policy *new)
 695 {
 696         struct xfrm_policy_queue *pq = &old->polq;
 697         struct sk_buff_head list;
 698
 699         if (skb_queue_empty(&pq->hold_queue))
 700                 return;
 701
 702         __skb_queue_head_init(&list);
 703
 704         spin_lock_bh(&pq->hold_queue.lock);
 705         skb_queue_splice_init(&pq->hold_queue, &list);
 706         if (del_timer(&pq->hold_timer))
 707                 xfrm_pol_put(old);
 708         spin_unlock_bh(&pq->hold_queue.lock);
 709
 710         pq = &new->polq;
 711
 712         spin_lock_bh(&pq->hold_queue.lock);
 713         skb_queue_splice(&list, &pq->hold_queue);
 714         pq->timeout = XFRM_QUEUE_TMO_MIN;
 715         if (!mod_timer(&pq->hold_timer, jiffies))
 716                 xfrm_pol_hold(new);
 717         spin_unlock_bh(&pq->hold_queue.lock);
 718 }
 719
 720 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
 721                                    struct xfrm_policy *pol)
 722 {
 723         u32 mark = policy->mark.v & policy->mark.m;
 724
 725         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
 726                 return true;
 727
 728         if ((mark & pol->mark.m) == pol->mark.v &&
 729             policy->priority == pol->priority)
 730                 return true;
 731
 732         return false;
 733 }
 734
 735 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 736 {
 737         struct net *net = xp_net(policy);
 738         struct xfrm_policy *pol;
 739         struct xfrm_policy *delpol;
 740         struct hlist_head *chain;
 741         struct hlist_node *newpos;
 742
 743         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 744         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 745         delpol = NULL;
 746         newpos = NULL;
 747         hlist_for_each_entry(pol, chain, bydst) {
 748                 if (pol->type == policy->type &&
 749                     !selector_cmp(&pol->selector, &policy->selector) &&
 750                     xfrm_policy_mark_match(policy, pol) &&
 751                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 752                     !WARN_ON(delpol)) {
 753                         if (excl) {
 754                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 755                                 return -EEXIST;
 756                         }
 757                         delpol = pol;
 758                         if (policy->priority > pol->priority)
 759                                 continue;
 760                 } else if (policy->priority >= pol->priority) {
 761                         newpos = &pol->bydst;
 762                         continue;
 763                 }
 764                 if (delpol)
 765                         break;
 766         }
 767         if (newpos)
 768                 hlist_add_behind(&policy->bydst, newpos);
 769         else
 770                 hlist_add_head(&policy->bydst, chain);
 771         __xfrm_policy_link(policy, dir);
 772
 773         /* After previous checking, family can either be AF_INET or AF_INET6 */
 774         if (policy->family == AF_INET)
 775                 rt_genid_bump_ipv4(net);
 776         else
 777                 rt_genid_bump_ipv6(net);
 778
 779         if (delpol) {
 780                 xfrm_policy_requeue(delpol, policy);
 781                 __xfrm_policy_unlink(delpol, dir);
 782         }
 783         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
 784         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 785         policy->curlft.add_time = get_seconds();
 786         policy->curlft.use_time = 0;
 787         if (!mod_timer(&policy->timer, jiffies + HZ))
 788                 xfrm_pol_hold(policy);
 789         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 790
 791         if (delpol)
 792                 xfrm_policy_kill(delpol);
 793         else if (xfrm_bydst_should_resize(net, dir, NULL))
 794                 schedule_work(&net->xfrm.policy_hash_work);
 795
 796         return 0;
 797 }
 798 EXPORT_SYMBOL(xfrm_policy_insert);
 799
 800 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
 801                                           int dir, struct xfrm_selector *sel,
 802                                           struct xfrm_sec_ctx *ctx, int delete,
 803                                           int *err)
 804 {
 805         struct xfrm_policy *pol, *ret;
 806         struct hlist_head *chain;
 807
 808         *err = 0;
 809         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 810         chain = policy_hash_bysel(net, sel, sel->family, dir);
 811         ret = NULL;
 812         hlist_for_each_entry(pol, chain, bydst) {
 813                 if (pol->type == type &&
 814                     (mark & pol->mark.m) == pol->mark.v &&
 815                     !selector_cmp(sel, &pol->selector) &&
 816                     xfrm_sec_ctx_match(ctx, pol->security)) {
 817                         xfrm_pol_hold(pol);
 818                         if (delete) {
 819                                 *err = security_xfrm_policy_delete(
 820                                                                 pol->security);
 821                                 if (*err) {
 822                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 823                                         return pol;
 824                                 }
 825                                 __xfrm_policy_unlink(pol, dir);
 826                         }
 827                         ret = pol;
 828                         break;
 829                 }
 830         }
 831         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 832
 833         if (ret && delete)
 834                 xfrm_policy_kill(ret);
 835         return ret;
 836 }
 837 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 838
 839 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
 840                                      int dir, u32 id, int delete, int *err)
 841 {
 842         struct xfrm_policy *pol, *ret;
 843         struct hlist_head *chain;
 844
 845         *err = -ENOENT;
 846         if (xfrm_policy_id2dir(id) != dir)
 847                 return NULL;
 848
 849         *err = 0;
 850         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 851         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 852         ret = NULL;
 853         hlist_for_each_entry(pol, chain, byidx) {
 854                 if (pol->type == type && pol->index == id &&
 855                     (mark & pol->mark.m) == pol->mark.v) {
 856                         xfrm_pol_hold(pol);
 857                         if (delete) {
 858                                 *err = security_xfrm_policy_delete(
 859                                                                 pol->security);
 860                                 if (*err) {
 861                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 862                                         return pol;
 863                                 }
 864                                 __xfrm_policy_unlink(pol, dir);
 865                         }
 866                         ret = pol;
 867                         break;
 868                 }
 869         }
 870         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 871
 872         if (ret && delete)
 873                 xfrm_policy_kill(ret);
 874         return ret;
 875 }
 876 EXPORT_SYMBOL(xfrm_policy_byid);
 877
 878 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 879 static inline int
 880 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 881 {
 882         int dir, err = 0;
 883
 884         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 885                 struct xfrm_policy *pol;
 886                 int i;
 887
 888                 hlist_for_each_entry(pol,
 889                                      &net->xfrm.policy_inexact[dir], bydst) {
 890                         if (pol->type != type)
 891                                 continue;
 892                         err = security_xfrm_policy_delete(pol->security);
 893                         if (err) {
 894                                 xfrm_audit_policy_delete(pol, 0, task_valid);
 895                                 return err;
 896                         }
 897                 }
 898                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 899                         hlist_for_each_entry(pol,
 900                                              net->xfrm.policy_bydst[dir].table + i,
 901                                              bydst) {
 902                                 if (pol->type != type)
 903                                         continue;
 904                                 err = security_xfrm_policy_delete(
 905                                                                 pol->security);
 906                                 if (err) {
 907                                         xfrm_audit_policy_delete(pol, 0,
 908                                                                  task_valid);
 909                                         return err;
 910                                 }
 911                         }
 912                 }
 913         }
 914         return err;
 915 }
 916 #else
 917 static inline int
 918 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
 919 {
 920         return 0;
 921 }
 922 #endif
 923
 924 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
 925 {
 926         int dir, err = 0, cnt = 0;
 927
 928         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 929
 930         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
 931         if (err)
 932                 goto out;
 933
 934         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 935                 struct xfrm_policy *pol;
 936                 int i;
 937
 938         again1:
 939                 hlist_for_each_entry(pol,
 940                                      &net->xfrm.policy_inexact[dir], bydst) {
 941                         if (pol->type != type)
 942                                 continue;
 943                         __xfrm_policy_unlink(pol, dir);
 944                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 945                         cnt++;
 946
 947                         xfrm_audit_policy_delete(pol, 1, task_valid);
 948
 949                         xfrm_policy_kill(pol);
 950
 951                         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 952                         goto again1;
 953                 }
 954
 955                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 956         again2:
 957                         hlist_for_each_entry(pol,
 958                                              net->xfrm.policy_bydst[dir].table + i,
 959                                              bydst) {
 960                                 if (pol->type != type)
 961                                         continue;
 962                                 __xfrm_policy_unlink(pol, dir);
 963                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 964                                 cnt++;
 965
 966                                 xfrm_audit_policy_delete(pol, 1, task_valid);
 967                                 xfrm_policy_kill(pol);
 968
 969                                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 970                                 goto again2;
 971                         }
 972                 }
 973
 974         }
 975         if (!cnt)
 976                 err = -ESRCH;
 977         else
 978                 xfrm_policy_cache_flush();
 979 out:
 980         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 981         return err;
 982 }
 983 EXPORT_SYMBOL(xfrm_policy_flush);
 984
 985 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 986                      int (*func)(struct xfrm_policy *, int, int, void*),
 987                      void *data)
 988 {
 989         struct xfrm_policy *pol;
 990         struct xfrm_policy_walk_entry *x;
 991         int error = 0;
 992
 993         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
 994             walk->type != XFRM_POLICY_TYPE_ANY)
 995                 return -EINVAL;
 996
 997         if (list_empty(&walk->walk.all) && walk->seq != 0)
 998                 return 0;
 999
1000         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1001         if (list_empty(&walk->walk.all))
1002                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1003         else
1004                 x = list_first_entry(&walk->walk.all,
1005                                      struct xfrm_policy_walk_entry, all);
1006
1007         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1008                 if (x->dead)
1009                         continue;
1010                 pol = container_of(x, struct xfrm_policy, walk);
1011                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1012                     walk->type != pol->type)
1013                         continue;
1014                 error = func(pol, xfrm_policy_id2dir(pol->index),
1015                              walk->seq, data);
1016                 if (error) {
1017                         list_move_tail(&walk->walk.all, &x->all);
1018                         goto out;
1019                 }
1020                 walk->seq++;
1021         }
1022         if (walk->seq == 0) {
1023                 error = -ENOENT;
1024                 goto out;
1025         }
1026         list_del_init(&walk->walk.all);
1027 out:
1028         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1029         return error;
1030 }
1031 EXPORT_SYMBOL(xfrm_policy_walk);
1032
1033 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1034 {
1035         INIT_LIST_HEAD(&walk->walk.all);
1036         walk->walk.dead = 1;
1037         walk->type = type;
1038         walk->seq = 0;
1039 }
1040 EXPORT_SYMBOL(xfrm_policy_walk_init);
1041
1042 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1043 {
1044         if (list_empty(&walk->walk.all))
1045                 return;
1046
1047         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1048         list_del(&walk->walk.all);
1049         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1050 }
1051 EXPORT_SYMBOL(xfrm_policy_walk_done);
1052
1053 /*
1054  * Find policy to apply to this flow.
1055  *
1056  * Returns 0 if policy found, else an -errno.
1057  */
1058 static int xfrm_policy_match(const struct xfrm_policy *pol,
1059                              const struct flowi *fl,
1060                              u8 type, u16 family, int dir)
1061 {
1062         const struct xfrm_selector *sel = &pol->selector;
1063         int ret = -ESRCH;
1064         bool match;
1065
1066         if (pol->family != family ||
1067             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1068             pol->type != type)
1069                 return ret;
1070
1071         match = xfrm_selector_match(sel, fl, family);
1072         if (match)
1073                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1074                                                   dir);
1075
1076         return ret;
1077 }
1078
1079 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
1080                                                      const struct flowi *fl,
1081                                                      u16 family, u8 dir)
1082 {
1083         int err;
1084         struct xfrm_policy *pol, *ret;
1085         const xfrm_address_t *daddr, *saddr;
1086         struct hlist_head *chain;
1087         unsigned int sequence;
1088         u32 priority;
1089
1090         daddr = xfrm_flowi_daddr(fl, family);
1091         saddr = xfrm_flowi_saddr(fl, family);
1092         if (unlikely(!daddr || !saddr))
1093                 return NULL;
1094
1095         rcu_read_lock();
1096  retry:
1097         do {
1098                 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
1099                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
1100         } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
1101
1102         priority = ~0U;
1103         ret = NULL;
1104         hlist_for_each_entry_rcu(pol, chain, bydst) {
1105                 err = xfrm_policy_match(pol, fl, type, family, dir);
1106                 if (err) {
1107                         if (err == -ESRCH)
1108                                 continue;
1109                         else {
1110                                 ret = ERR_PTR(err);
1111                                 goto fail;
1112                         }
1113                 } else {
1114                         ret = pol;
1115                         priority = ret->priority;
1116                         break;
1117                 }
1118         }
1119         chain = &net->xfrm.policy_inexact[dir];
1120         hlist_for_each_entry_rcu(pol, chain, bydst) {
1121                 if ((pol->priority >= priority) && ret)
1122                         break;
1123
1124                 err = xfrm_policy_match(pol, fl, type, family, dir);
1125                 if (err) {
1126                         if (err == -ESRCH)
1127                                 continue;
1128                         else {
1129                                 ret = ERR_PTR(err);
1130                                 goto fail;
1131                         }
1132                 } else {
1133                         ret = pol;
1134                         break;
1135                 }
1136         }
1137
1138         if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
1139                 goto retry;
1140
1141         if (ret && !xfrm_pol_hold_rcu(ret))
1142                 goto retry;
1143 fail:
1144         rcu_read_unlock();
1145
1146         return ret;
1147 }
1148
1149 static struct xfrm_policy *
1150 xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
1151 {
1152 #ifdef CONFIG_XFRM_SUB_POLICY
1153         struct xfrm_policy *pol;
1154
1155         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
1156         if (pol != NULL)
1157                 return pol;
1158 #endif
1159         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1160 }
1161
1162 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
1163                                                  const struct flowi *fl, u16 family)
1164 {
1165         struct xfrm_policy *pol;
1166
1167         rcu_read_lock();
1168  again:
1169         pol = rcu_dereference(sk->sk_policy[dir]);
1170         if (pol != NULL) {
1171                 bool match;
1172                 int err = 0;
1173
1174                 if (pol->family != family) {
1175                         pol = NULL;
1176                         goto out;
1177                 }
1178
1179                 match = xfrm_selector_match(&pol->selector, fl, family);
1180                 if (match) {
1181                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1182                                 pol = NULL;
1183                                 goto out;
1184                         }
1185                         err = security_xfrm_policy_lookup(pol->security,
1186                                                       fl->flowi_secid,
1187                                                       dir);
1188                         if (!err) {
1189                                 if (!xfrm_pol_hold_rcu(pol))
1190                                         goto again;
1191                         } else if (err == -ESRCH) {
1192                                 pol = NULL;
1193                         } else {
1194                                 pol = ERR_PTR(err);
1195                         }
1196                 } else
1197                         pol = NULL;
1198         }
1199 out:
1200         rcu_read_unlock();
1201         return pol;
1202 }
1203
1204 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1205 {
1206         struct net *net = xp_net(pol);
1207
1208         list_add(&pol->walk.all, &net->xfrm.policy_all);
1209         net->xfrm.policy_count[dir]++;
1210         xfrm_pol_hold(pol);
1211 }
1212
1213 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1214                                                 int dir)
1215 {
1216         struct net *net = xp_net(pol);
1217
1218         if (list_empty(&pol->walk.all))
1219                 return NULL;
1220
1221         /* Socket policies are not hashed. */
1222         if (!hlist_unhashed(&pol->bydst)) {
1223                 hlist_del_rcu(&pol->bydst);
1224                 hlist_del(&pol->byidx);
1225         }
1226
1227         list_del_init(&pol->walk.all);
1228         net->xfrm.policy_count[dir]--;
1229
1230         return pol;
1231 }
1232
1233 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
1234 {
1235         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
1236 }
1237
1238 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
1239 {
1240         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
1241 }
1242
1243 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1244 {
1245         struct net *net = xp_net(pol);
1246
1247         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1248         pol = __xfrm_policy_unlink(pol, dir);
1249         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1250         if (pol) {
1251                 xfrm_policy_kill(pol);
1252                 return 0;
1253         }
1254         return -ENOENT;
1255 }
1256 EXPORT_SYMBOL(xfrm_policy_delete);
1257
1258 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1259 {
1260         struct net *net = xp_net(pol);
1261         struct xfrm_policy *old_pol;
1262
1263 #ifdef CONFIG_XFRM_SUB_POLICY
1264         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1265                 return -EINVAL;
1266 #endif
1267
1268         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1269         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
1270                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
1271         if (pol) {
1272                 pol->curlft.add_time = get_seconds();
1273                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
1274                 xfrm_sk_policy_link(pol, dir);
1275         }
1276         rcu_assign_pointer(sk->sk_policy[dir], pol);
1277         if (old_pol) {
1278                 if (pol)
1279                         xfrm_policy_requeue(old_pol, pol);
1280
1281                 /* Unlinking succeeds always. This is the only function
1282                  * allowed to delete or replace socket policy.
1283                  */
1284                 xfrm_sk_policy_unlink(old_pol, dir);
1285         }
1286         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1287
1288         if (old_pol) {
1289                 xfrm_policy_kill(old_pol);
1290         }
1291         return 0;
1292 }
1293
1294 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1295 {
1296         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1297         struct net *net = xp_net(old);
1298
1299         if (newp) {
1300                 newp->selector = old->selector;
1301                 if (security_xfrm_policy_clone(old->security,
1302                                                &newp->security)) {
1303                         kfree(newp);
1304                         return NULL;  /* ENOMEM */
1305                 }
1306                 newp->lft = old->lft;
1307                 newp->curlft = old->curlft;
1308                 newp->mark = old->mark;
1309                 newp->action = old->action;
1310                 newp->flags = old->flags;
1311                 newp->xfrm_nr = old->xfrm_nr;
1312                 newp->index = old->index;
1313                 newp->type = old->type;
1314                 newp->family = old->family;
1315                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1316                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1317                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1318                 xfrm_sk_policy_link(newp, dir);
1319                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1320                 xfrm_pol_put(newp);
1321         }
1322         return newp;
1323 }
1324
1325 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
1326 {
1327         const struct xfrm_policy *p;
1328         struct xfrm_policy *np;
1329         int i, ret = 0;
1330
1331         rcu_read_lock();
1332         for (i = 0; i < 2; i++) {
1333                 p = rcu_dereference(osk->sk_policy[i]);
1334                 if (p) {
1335                         np = clone_policy(p, i);
1336                         if (unlikely(!np)) {
1337                                 ret = -ENOMEM;
1338                                 break;
1339                         }
1340                         rcu_assign_pointer(sk->sk_policy[i], np);
1341                 }
1342         }
1343         rcu_read_unlock();
1344         return ret;
1345 }
1346
1347 static int
1348 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
1349                xfrm_address_t *remote, unsigned short family, u32 mark)
1350 {
1351         int err;
1352         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1353
1354         if (unlikely(afinfo == NULL))
1355                 return -EINVAL;
1356         err = afinfo->get_saddr(net, oif, local, remote, mark);
1357         rcu_read_unlock();
1358         return err;
1359 }
1360
1361 /* Resolve list of templates for the flow, given policy. */
1362
1363 static int
1364 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1365                       struct xfrm_state **xfrm, unsigned short family)
1366 {
1367         struct net *net = xp_net(policy);
1368         int nx;
1369         int i, error;
1370         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1371         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1372         xfrm_address_t tmp;
1373
1374         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
1375                 struct xfrm_state *x;
1376                 xfrm_address_t *remote = daddr;
1377                 xfrm_address_t *local  = saddr;
1378                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1379
1380                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1381                     tmpl->mode == XFRM_MODE_BEET) {
1382                         remote = &tmpl->id.daddr;
1383                         local = &tmpl->saddr;
1384                         if (xfrm_addr_any(local, tmpl->encap_family)) {
1385                                 error = xfrm_get_saddr(net, fl->flowi_oif,
1386                                                        &tmp, remote,
1387                                                        tmpl->encap_family, 0);
1388                                 if (error)
1389                                         goto fail;
1390                                 local = &tmp;
1391                         }
1392                 }
1393
1394                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1395
1396                 if (x && x->km.state == XFRM_STATE_VALID) {
1397                         xfrm[nx++] = x;
1398                         daddr = remote;
1399                         saddr = local;
1400                         continue;
1401                 }
1402                 if (x) {
1403                         error = (x->km.state == XFRM_STATE_ERROR ?
1404                                  -EINVAL : -EAGAIN);
1405                         xfrm_state_put(x);
1406                 } else if (error == -ESRCH) {
1407                         error = -EAGAIN;
1408                 }
1409
1410                 if (!tmpl->optional)
1411                         goto fail;
1412         }
1413         return nx;
1414
1415 fail:
1416         for (nx--; nx >= 0; nx--)
1417                 xfrm_state_put(xfrm[nx]);
1418         return error;
1419 }
1420
1421 static int
1422 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1423                   struct xfrm_state **xfrm, unsigned short family)
1424 {
1425         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1426         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1427         int cnx = 0;
1428         int error;
1429         int ret;
1430         int i;
1431
1432         for (i = 0; i < npols; i++) {
1433                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1434                         error = -ENOBUFS;
1435                         goto fail;
1436                 }
1437
1438                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1439                 if (ret < 0) {
1440                         error = ret;
1441                         goto fail;
1442                 } else
1443                         cnx += ret;
1444         }
1445
1446         /* found states are sorted for outbound processing */
1447         if (npols > 1)
1448                 xfrm_state_sort(xfrm, tpp, cnx, family);
1449
1450         return cnx;
1451
1452  fail:
1453         for (cnx--; cnx >= 0; cnx--)
1454                 xfrm_state_put(tpp[cnx]);
1455         return error;
1456
1457 }
1458
1459 static int xfrm_get_tos(const struct flowi *fl, int family)
1460 {
1461         const struct xfrm_policy_afinfo *afinfo;
1462         int tos = 0;
1463
1464         afinfo = xfrm_policy_get_afinfo(family);
1465         tos = afinfo ? afinfo->get_tos(fl) : 0;
1466
1467         rcu_read_unlock();
1468
1469         return tos;
1470 }
1471
1472 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1473 {
1474         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1475         struct dst_ops *dst_ops;
1476         struct xfrm_dst *xdst;
1477
1478         if (!afinfo)
1479                 return ERR_PTR(-EINVAL);
1480
1481         switch (family) {
1482         case AF_INET:
1483                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1484                 break;
1485 #if IS_ENABLED(CONFIG_IPV6)
1486         case AF_INET6:
1487                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1488                 break;
1489 #endif
1490         default:
1491                 BUG();
1492         }
1493         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
1494
1495         if (likely(xdst)) {
1496                 struct dst_entry *dst = &xdst->u.dst;
1497
1498                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1499         } else
1500                 xdst = ERR_PTR(-ENOBUFS);
1501
1502         rcu_read_unlock();
1503
1504         return xdst;
1505 }
1506
1507 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1508                                  int nfheader_len)
1509 {
1510         const struct xfrm_policy_afinfo *afinfo =
1511                 xfrm_policy_get_afinfo(dst->ops->family);
1512         int err;
1513
1514         if (!afinfo)
1515                 return -EINVAL;
1516
1517         err = afinfo->init_path(path, dst, nfheader_len);
1518
1519         rcu_read_unlock();
1520
1521         return err;
1522 }
1523
1524 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1525                                 const struct flowi *fl)
1526 {
1527         const struct xfrm_policy_afinfo *afinfo =
1528                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1529         int err;
1530
1531         if (!afinfo)
1532                 return -EINVAL;
1533
1534         err = afinfo->fill_dst(xdst, dev, fl);
1535
1536         rcu_read_unlock();
1537
1538         return err;
1539 }
1540
1541
1542 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1543  * all the metrics... Shortly, bundle a bundle.
1544  */
1545
1546 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1547                                             struct xfrm_state **xfrm, int nx,
1548                                             const struct flowi *fl,
1549                                             struct dst_entry *dst)
1550 {
1551         struct net *net = xp_net(policy);
1552         unsigned long now = jiffies;
1553         struct net_device *dev;
1554         struct xfrm_mode *inner_mode;
1555         struct dst_entry *dst_prev = NULL;
1556         struct dst_entry *dst0 = NULL;
1557         int i = 0;
1558         int err;
1559         int header_len = 0;
1560         int nfheader_len = 0;
1561         int trailer_len = 0;
1562         int tos;
1563         int family = policy->selector.family;
1564         xfrm_address_t saddr, daddr;
1565
1566         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1567
1568         tos = xfrm_get_tos(fl, family);
1569
1570         dst_hold(dst);
1571
1572         for (; i < nx; i++) {
1573                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1574                 struct dst_entry *dst1 = &xdst->u.dst;
1575
1576                 err = PTR_ERR(xdst);
1577                 if (IS_ERR(xdst)) {
1578                         dst_release(dst);
1579                         goto put_states;
1580                 }
1581
1582                 if (!dst_prev)
1583                         dst0 = dst1;
1584                 else
1585                         /* Ref count is taken during xfrm_alloc_dst()
1586                          * No need to do dst_clone() on dst1
1587                          */
1588                         dst_prev->child = dst1;
1589
1590                 if (xfrm[i]->sel.family == AF_UNSPEC) {
1591                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
1592                                                         xfrm_af2proto(family));
1593                         if (!inner_mode) {
1594                                 err = -EAFNOSUPPORT;
1595                                 dst_release(dst);
1596                                 goto put_states;
1597                         }
1598                 } else
1599                         inner_mode = xfrm[i]->inner_mode;
1600
1601                 xdst->route = dst;
1602                 dst_copy_metrics(dst1, dst);
1603
1604                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1605                         family = xfrm[i]->props.family;
1606                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
1607                                               &saddr, &daddr, family,
1608                                               xfrm[i]->props.output_mark);
1609                         err = PTR_ERR(dst);
1610                         if (IS_ERR(dst))
1611                                 goto put_states;
1612                 } else
1613                         dst_hold(dst);
1614
1615                 dst1->xfrm = xfrm[i];
1616                 xdst->xfrm_genid = xfrm[i]->genid;
1617
1618                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1619                 dst1->flags |= DST_HOST;
1620                 dst1->lastuse = now;
1621
1622                 dst1->input = dst_discard;
1623                 dst1->output = inner_mode->afinfo->output;
1624
1625                 dst1->next = dst_prev;
1626                 dst_prev = dst1;
1627
1628                 header_len += xfrm[i]->props.header_len;
1629                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1630                         nfheader_len += xfrm[i]->props.header_len;
1631                 trailer_len += xfrm[i]->props.trailer_len;
1632         }
1633
1634         dst_prev->child = dst;
1635         dst0->path = dst;
1636
1637         err = -ENODEV;
1638         dev = dst->dev;
1639         if (!dev)
1640                 goto free_dst;
1641
1642         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1643         xfrm_init_pmtu(dst_prev);
1644
1645         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1646                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1647
1648                 err = xfrm_fill_dst(xdst, dev, fl);
1649                 if (err)
1650                         goto free_dst;
1651
1652                 dst_prev->header_len = header_len;
1653                 dst_prev->trailer_len = trailer_len;
1654                 header_len -= xdst->u.dst.xfrm->props.header_len;
1655                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1656         }
1657
1658 out:
1659         return dst0;
1660
1661 put_states:
1662         for (; i < nx; i++)
1663                 xfrm_state_put(xfrm[i]);
1664 free_dst:
1665         if (dst0)
1666                 dst_release_immediate(dst0);
1667         dst0 = 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         local_bh_disable();
1747         rcu_read_lock();
1748         for_each_possible_cpu(cpu) {
1749                 old = per_cpu(xfrm_last_dst, cpu);
1750                 if (old && !xfrm_bundle_ok(old)) {
1751                         if (smp_processor_id() == cpu) {
1752                                 __xfrm_pcpu_work_fn();
1753                                 continue;
1754                         }
1755                         found = true;
1756                         break;
1757                 }
1758         }
1759
1760         rcu_read_unlock();
1761         local_bh_enable();
1762
1763         if (!found)
1764                 return;
1765
1766         get_online_cpus();
1767
1768         for_each_possible_cpu(cpu) {
1769                 bool bundle_release;
1770
1771                 rcu_read_lock();
1772                 old = per_cpu(xfrm_last_dst, cpu);
1773                 bundle_release = old && !xfrm_bundle_ok(old);
1774                 rcu_read_unlock();
1775
1776                 if (!bundle_release)
1777                         continue;
1778
1779                 if (cpu_online(cpu)) {
1780                         schedule_work_on(cpu, &xfrm_pcpu_work[cpu]);
1781                         continue;
1782                 }
1783
1784                 rcu_read_lock();
1785                 old = per_cpu(xfrm_last_dst, cpu);
1786                 if (old && !xfrm_bundle_ok(old)) {
1787                         per_cpu(xfrm_last_dst, cpu) = NULL;
1788                         dst_release(&old->u.dst);
1789                 }
1790                 rcu_read_unlock();
1791         }
1792
1793         put_online_cpus();
1794 }
1795
1796 static bool xfrm_xdst_can_reuse(struct xfrm_dst *xdst,
1797                                 struct xfrm_state * const xfrm[],
1798                                 int num)
1799 {
1800         const struct dst_entry *dst = &xdst->u.dst;
1801         int i;
1802
1803         if (xdst->num_xfrms != num)
1804                 return false;
1805
1806         for (i = 0; i < num; i++) {
1807                 if (!dst || dst->xfrm != xfrm[i])
1808                         return false;
1809                 dst = dst->child;
1810         }
1811
1812         return xfrm_bundle_ok(xdst);
1813 }
1814
1815 static struct xfrm_dst *
1816 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1817                                const struct flowi *fl, u16 family,
1818                                struct dst_entry *dst_orig)
1819 {
1820         struct net *net = xp_net(pols[0]);
1821         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1822         struct xfrm_dst *xdst, *old;
1823         struct dst_entry *dst;
1824         int err;
1825
1826         /* Try to instantiate a bundle */
1827         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1828         if (err <= 0) {
1829                 if (err != 0 && err != -EAGAIN)
1830                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1831                 return ERR_PTR(err);
1832         }
1833
1834         xdst = this_cpu_read(xfrm_last_dst);
1835         if (xdst &&
1836             xdst->u.dst.dev == dst_orig->dev &&
1837             xdst->num_pols == num_pols &&
1838             memcmp(xdst->pols, pols,
1839                    sizeof(struct xfrm_policy *) * num_pols) == 0 &&
1840             xfrm_xdst_can_reuse(xdst, xfrm, err)) {
1841                 dst_hold(&xdst->u.dst);
1842                 xfrm_pols_put(pols, num_pols);
1843                 while (err > 0)
1844                         xfrm_state_put(xfrm[--err]);
1845                 return xdst;
1846         }
1847
1848         old = xdst;
1849
1850         dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1851         if (IS_ERR(dst)) {
1852                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1853                 return ERR_CAST(dst);
1854         }
1855
1856         xdst = (struct xfrm_dst *)dst;
1857         xdst->num_xfrms = err;
1858         xdst->num_pols = num_pols;
1859         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
1860         xdst->policy_genid = atomic_read(&pols[0]->genid);
1861
1862         atomic_set(&xdst->u.dst.__refcnt, 2);
1863         xfrm_last_dst_update(xdst, old);
1864
1865         return xdst;
1866 }
1867
1868 static void xfrm_policy_queue_process(struct timer_list *t)
1869 {
1870         struct sk_buff *skb;
1871         struct sock *sk;
1872         struct dst_entry *dst;
1873         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
1874         struct net *net = xp_net(pol);
1875         struct xfrm_policy_queue *pq = &pol->polq;
1876         struct flowi fl;
1877         struct sk_buff_head list;
1878
1879         spin_lock(&pq->hold_queue.lock);
1880         skb = skb_peek(&pq->hold_queue);
1881         if (!skb) {
1882                 spin_unlock(&pq->hold_queue.lock);
1883                 goto out;
1884         }
1885         dst = skb_dst(skb);
1886         sk = skb->sk;
1887         xfrm_decode_session(skb, &fl, dst->ops->family);
1888         spin_unlock(&pq->hold_queue.lock);
1889
1890         dst_hold(dst->path);
1891         dst = xfrm_lookup(net, dst->path, &fl, sk, 0);
1892         if (IS_ERR(dst))
1893                 goto purge_queue;
1894
1895         if (dst->flags & DST_XFRM_QUEUE) {
1896                 dst_release(dst);
1897
1898                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
1899                         goto purge_queue;
1900
1901                 pq->timeout = pq->timeout << 1;
1902                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
1903                         xfrm_pol_hold(pol);
1904         goto out;
1905         }
1906
1907         dst_release(dst);
1908
1909         __skb_queue_head_init(&list);
1910
1911         spin_lock(&pq->hold_queue.lock);
1912         pq->timeout = 0;
1913         skb_queue_splice_init(&pq->hold_queue, &list);
1914         spin_unlock(&pq->hold_queue.lock);
1915
1916         while (!skb_queue_empty(&list)) {
1917                 skb = __skb_dequeue(&list);
1918
1919                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
1920                 dst_hold(skb_dst(skb)->path);
1921                 dst = xfrm_lookup(net, skb_dst(skb)->path, &fl, skb->sk, 0);
1922                 if (IS_ERR(dst)) {
1923                         kfree_skb(skb);
1924                         continue;
1925                 }
1926
1927                 nf_reset(skb);
1928                 skb_dst_drop(skb);
1929                 skb_dst_set(skb, dst);
1930
1931                 dst_output(net, skb->sk, skb);
1932         }
1933
1934 out:
1935         xfrm_pol_put(pol);
1936         return;
1937
1938 purge_queue:
1939         pq->timeout = 0;
1940         skb_queue_purge(&pq->hold_queue);
1941         xfrm_pol_put(pol);
1942 }
1943
1944 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
1945 {
1946         unsigned long sched_next;
1947         struct dst_entry *dst = skb_dst(skb);
1948         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
1949         struct xfrm_policy *pol = xdst->pols[0];
1950         struct xfrm_policy_queue *pq = &pol->polq;
1951
1952         if (unlikely(skb_fclone_busy(sk, skb))) {
1953                 kfree_skb(skb);
1954                 return 0;
1955         }
1956
1957         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
1958                 kfree_skb(skb);
1959                 return -EAGAIN;
1960         }
1961
1962         skb_dst_force(skb);
1963
1964         spin_lock_bh(&pq->hold_queue.lock);
1965
1966         if (!pq->timeout)
1967                 pq->timeout = XFRM_QUEUE_TMO_MIN;
1968
1969         sched_next = jiffies + pq->timeout;
1970
1971         if (del_timer(&pq->hold_timer)) {
1972                 if (time_before(pq->hold_timer.expires, sched_next))
1973                         sched_next = pq->hold_timer.expires;
1974                 xfrm_pol_put(pol);
1975         }
1976
1977         __skb_queue_tail(&pq->hold_queue, skb);
1978         if (!mod_timer(&pq->hold_timer, sched_next))
1979                 xfrm_pol_hold(pol);
1980
1981         spin_unlock_bh(&pq->hold_queue.lock);
1982
1983         return 0;
1984 }
1985
1986 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
1987                                                  struct xfrm_flo *xflo,
1988                                                  const struct flowi *fl,
1989                                                  int num_xfrms,
1990                                                  u16 family)
1991 {
1992         int err;
1993         struct net_device *dev;
1994         struct dst_entry *dst;
1995         struct dst_entry *dst1;
1996         struct xfrm_dst *xdst;
1997
1998         xdst = xfrm_alloc_dst(net, family);
1999         if (IS_ERR(xdst))
2000                 return xdst;
2001
2002         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2003             net->xfrm.sysctl_larval_drop ||
2004             num_xfrms <= 0)
2005                 return xdst;
2006
2007         dst = xflo->dst_orig;
2008         dst1 = &xdst->u.dst;
2009         dst_hold(dst);
2010         xdst->route = dst;
2011
2012         dst_copy_metrics(dst1, dst);
2013
2014         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2015         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2016         dst1->lastuse = jiffies;
2017
2018         dst1->input = dst_discard;
2019         dst1->output = xdst_queue_output;
2020
2021         dst_hold(dst);
2022         dst1->child = dst;
2023         dst1->path = dst;
2024
2025         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2026
2027         err = -ENODEV;
2028         dev = dst->dev;
2029         if (!dev)
2030                 goto free_dst;
2031
2032         err = xfrm_fill_dst(xdst, dev, fl);
2033         if (err)
2034                 goto free_dst;
2035
2036 out:
2037         return xdst;
2038
2039 free_dst:
2040         dst_release(dst1);
2041         xdst = ERR_PTR(err);
2042         goto out;
2043 }
2044
2045 static struct xfrm_dst *
2046 xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo)
2047 {
2048         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2049         int num_pols = 0, num_xfrms = 0, err;
2050         struct xfrm_dst *xdst;
2051
2052         /* Resolve policies to use if we couldn't get them from
2053          * previous cache entry */
2054         num_pols = 1;
2055         pols[0] = xfrm_policy_lookup(net, fl, family, dir);
2056         err = xfrm_expand_policies(fl, family, pols,
2057                                            &num_pols, &num_xfrms);
2058         if (err < 0)
2059                 goto inc_error;
2060         if (num_pols == 0)
2061                 return NULL;
2062         if (num_xfrms <= 0)
2063                 goto make_dummy_bundle;
2064
2065         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2066                                                   xflo->dst_orig);
2067         if (IS_ERR(xdst)) {
2068                 err = PTR_ERR(xdst);
2069                 if (err != -EAGAIN)
2070                         goto error;
2071                 goto make_dummy_bundle;
2072         } else if (xdst == NULL) {
2073                 num_xfrms = 0;
2074                 goto make_dummy_bundle;
2075         }
2076
2077         return xdst;
2078
2079 make_dummy_bundle:
2080         /* We found policies, but there's no bundles to instantiate:
2081          * either because the policy blocks, has no transformations or
2082          * we could not build template (no xfrm_states).*/
2083         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2084         if (IS_ERR(xdst)) {
2085                 xfrm_pols_put(pols, num_pols);
2086                 return ERR_CAST(xdst);
2087         }
2088         xdst->num_pols = num_pols;
2089         xdst->num_xfrms = num_xfrms;
2090         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2091
2092         return xdst;
2093
2094 inc_error:
2095         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2096 error:
2097         xfrm_pols_put(pols, num_pols);
2098         return ERR_PTR(err);
2099 }
2100
2101 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2102                                         struct dst_entry *dst_orig)
2103 {
2104         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2105         struct dst_entry *ret;
2106
2107         if (!afinfo) {
2108                 dst_release(dst_orig);
2109                 return ERR_PTR(-EINVAL);
2110         } else {
2111                 ret = afinfo->blackhole_route(net, dst_orig);
2112         }
2113         rcu_read_unlock();
2114
2115         return ret;
2116 }
2117
2118 /* Main function: finds/creates a bundle for given flow.
2119  *
2120  * At the moment we eat a raw IP route. Mostly to speed up lookups
2121  * on interfaces with disabled IPsec.
2122  */
2123 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
2124                               const struct flowi *fl,
2125                               const struct sock *sk, int flags)
2126 {
2127         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2128         struct xfrm_dst *xdst;
2129         struct dst_entry *dst, *route;
2130         u16 family = dst_orig->ops->family;
2131         u8 dir = XFRM_POLICY_OUT;
2132         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
2133
2134         dst = NULL;
2135         xdst = NULL;
2136         route = NULL;
2137
2138         sk = sk_const_to_full_sk(sk);
2139         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
2140                 num_pols = 1;
2141                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family);
2142                 err = xfrm_expand_policies(fl, family, pols,
2143                                            &num_pols, &num_xfrms);
2144                 if (err < 0)
2145                         goto dropdst;
2146
2147                 if (num_pols) {
2148                         if (num_xfrms <= 0) {
2149                                 drop_pols = num_pols;
2150                                 goto no_transform;
2151                         }
2152
2153                         xdst = xfrm_resolve_and_create_bundle(
2154                                         pols, num_pols, fl,
2155                                         family, dst_orig);
2156                         if (IS_ERR(xdst)) {
2157                                 xfrm_pols_put(pols, num_pols);
2158                                 err = PTR_ERR(xdst);
2159                                 goto dropdst;
2160                         } else if (xdst == NULL) {
2161                                 num_xfrms = 0;
2162                                 drop_pols = num_pols;
2163                                 goto no_transform;
2164                         }
2165
2166                         route = xdst->route;
2167                 }
2168         }
2169
2170         if (xdst == NULL) {
2171                 struct xfrm_flo xflo;
2172
2173                 xflo.dst_orig = dst_orig;
2174                 xflo.flags = flags;
2175
2176                 /* To accelerate a bit...  */
2177                 if ((dst_orig->flags & DST_NOXFRM) ||
2178                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
2179                         goto nopol;
2180
2181                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo);
2182                 if (xdst == NULL)
2183                         goto nopol;
2184                 if (IS_ERR(xdst)) {
2185                         err = PTR_ERR(xdst);
2186                         goto dropdst;
2187                 }
2188
2189                 num_pols = xdst->num_pols;
2190                 num_xfrms = xdst->num_xfrms;
2191                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
2192                 route = xdst->route;
2193         }
2194
2195         dst = &xdst->u.dst;
2196         if (route == NULL && num_xfrms > 0) {
2197                 /* The only case when xfrm_bundle_lookup() returns a
2198                  * bundle with null route, is when the template could
2199                  * not be resolved. It means policies are there, but
2200                  * bundle could not be created, since we don't yet
2201                  * have the xfrm_state's. We need to wait for KM to
2202                  * negotiate new SA's or bail out with error.*/
2203                 if (net->xfrm.sysctl_larval_drop) {
2204                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2205                         err = -EREMOTE;
2206                         goto error;
2207                 }
2208
2209                 err = -EAGAIN;
2210
2211                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
2212                 goto error;
2213         }
2214
2215 no_transform:
2216         if (num_pols == 0)
2217                 goto nopol;
2218
2219         if ((flags & XFRM_LOOKUP_ICMP) &&
2220             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
2221                 err = -ENOENT;
2222                 goto error;
2223         }
2224
2225         for (i = 0; i < num_pols; i++)
2226                 pols[i]->curlft.use_time = get_seconds();
2227
2228         if (num_xfrms < 0) {
2229                 /* Prohibit the flow */
2230                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
2231                 err = -EPERM;
2232                 goto error;
2233         } else if (num_xfrms > 0) {
2234                 /* Flow transformed */
2235                 dst_release(dst_orig);
2236         } else {
2237                 /* Flow passes untransformed */
2238                 dst_release(dst);
2239                 dst = dst_orig;
2240         }
2241 ok:
2242         xfrm_pols_put(pols, drop_pols);
2243         if (dst && dst->xfrm &&
2244             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
2245                 dst->flags |= DST_XFRM_TUNNEL;
2246         return dst;
2247
2248 nopol:
2249         if (!(flags & XFRM_LOOKUP_ICMP)) {
2250                 dst = dst_orig;
2251                 goto ok;
2252         }
2253         err = -ENOENT;
2254 error:
2255         dst_release(dst);
2256 dropdst:
2257         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
2258                 dst_release(dst_orig);
2259         xfrm_pols_put(pols, drop_pols);
2260         return ERR_PTR(err);
2261 }
2262 EXPORT_SYMBOL(xfrm_lookup);
2263
2264 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
2265  * Otherwise we may send out blackholed packets.
2266  */
2267 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
2268                                     const struct flowi *fl,
2269                                     const struct sock *sk, int flags)
2270 {
2271         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
2272                                             flags | XFRM_LOOKUP_QUEUE |
2273                                             XFRM_LOOKUP_KEEP_DST_REF);
2274
2275         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
2276                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
2277
2278         return dst;
2279 }
2280 EXPORT_SYMBOL(xfrm_lookup_route);
2281
2282 static inline int
2283 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
2284 {
2285         struct xfrm_state *x;
2286
2287         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
2288                 return 0;
2289         x = skb->sp->xvec[idx];
2290         if (!x->type->reject)
2291                 return 0;
2292         return x->type->reject(x, skb, fl);
2293 }
2294
2295 /* When skb is transformed back to its "native" form, we have to
2296  * check policy restrictions. At the moment we make this in maximally
2297  * stupid way. Shame on me. :-) Of course, connected sockets must
2298  * have policy cached at them.
2299  */
2300
2301 static inline int
2302 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
2303               unsigned short family)
2304 {
2305         if (xfrm_state_kern(x))
2306                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
2307         return  x->id.proto == tmpl->id.proto &&
2308                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
2309                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
2310                 x->props.mode == tmpl->mode &&
2311                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
2312                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
2313                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
2314                   xfrm_state_addr_cmp(tmpl, x, family));
2315 }
2316
2317 /*
2318  * 0 or more than 0 is returned when validation is succeeded (either bypass
2319  * because of optional transport mode, or next index of the mathced secpath
2320  * state with the template.
2321  * -1 is returned when no matching template is found.
2322  * Otherwise "-2 - errored_index" is returned.
2323  */
2324 static inline int
2325 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
2326                unsigned short family)
2327 {
2328         int idx = start;
2329
2330         if (tmpl->optional) {
2331                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
2332                         return start;
2333         } else
2334                 start = -1;
2335         for (; idx < sp->len; idx++) {
2336                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2337                         return ++idx;
2338                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2339                         if (start == -1)
2340                                 start = -2-idx;
2341                         break;
2342                 }
2343         }
2344         return start;
2345 }
2346
2347 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2348                           unsigned int family, int reverse)
2349 {
2350         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2351         int err;
2352
2353         if (unlikely(afinfo == NULL))
2354                 return -EAFNOSUPPORT;
2355
2356         afinfo->decode_session(skb, fl, reverse);
2357         err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2358         rcu_read_unlock();
2359         return err;
2360 }
2361 EXPORT_SYMBOL(__xfrm_decode_session);
2362
2363 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2364 {
2365         for (; k < sp->len; k++) {
2366                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2367                         *idxp = k;
2368                         return 1;
2369                 }
2370         }
2371
2372         return 0;
2373 }
2374
2375 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2376                         unsigned short family)
2377 {
2378         struct net *net = dev_net(skb->dev);
2379         struct xfrm_policy *pol;
2380         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2381         int npols = 0;
2382         int xfrm_nr;
2383         int pi;
2384         int reverse;
2385         struct flowi fl;
2386         int xerr_idx = -1;
2387
2388         reverse = dir & ~XFRM_POLICY_MASK;
2389         dir &= XFRM_POLICY_MASK;
2390
2391         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2392                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2393                 return 0;
2394         }
2395
2396         nf_nat_decode_session(skb, &fl, family);
2397
2398         /* First, check used SA against their selectors. */
2399         if (skb->sp) {
2400                 int i;
2401
2402                 for (i = skb->sp->len-1; i >= 0; i--) {
2403                         struct xfrm_state *x = skb->sp->xvec[i];
2404                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
2405                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2406                                 return 0;
2407                         }
2408                 }
2409         }
2410
2411         pol = NULL;
2412         sk = sk_to_full_sk(sk);
2413         if (sk && sk->sk_policy[dir]) {
2414                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family);
2415                 if (IS_ERR(pol)) {
2416                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2417                         return 0;
2418                 }
2419         }
2420
2421         if (!pol)
2422                 pol = xfrm_policy_lookup(net, &fl, family, dir);
2423
2424         if (IS_ERR(pol)) {
2425                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2426                 return 0;
2427         }
2428
2429         if (!pol) {
2430                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2431                         xfrm_secpath_reject(xerr_idx, skb, &fl);
2432                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2433                         return 0;
2434                 }
2435                 return 1;
2436         }
2437
2438         pol->curlft.use_time = get_seconds();
2439
2440         pols[0] = pol;
2441         npols++;
2442 #ifdef CONFIG_XFRM_SUB_POLICY
2443         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2444                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2445                                                     &fl, family,
2446                                                     XFRM_POLICY_IN);
2447                 if (pols[1]) {
2448                         if (IS_ERR(pols[1])) {
2449                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2450                                 return 0;
2451                         }
2452                         pols[1]->curlft.use_time = get_seconds();
2453                         npols++;
2454                 }
2455         }
2456 #endif
2457
2458         if (pol->action == XFRM_POLICY_ALLOW) {
2459                 struct sec_path *sp;
2460                 static struct sec_path dummy;
2461                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2462                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2463                 struct xfrm_tmpl **tpp = tp;
2464                 int ti = 0;
2465                 int i, k;
2466
2467                 if ((sp = skb->sp) == NULL)
2468                         sp = &dummy;
2469
2470                 for (pi = 0; pi < npols; pi++) {
2471                         if (pols[pi] != pol &&
2472                             pols[pi]->action != XFRM_POLICY_ALLOW) {
2473                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2474                                 goto reject;
2475                         }
2476                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2477                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2478                                 goto reject_error;
2479                         }
2480                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2481                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2482                 }
2483                 xfrm_nr = ti;
2484                 if (npols > 1) {
2485                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
2486                         tpp = stp;
2487                 }
2488
2489                 /* For each tunnel xfrm, find the first matching tmpl.
2490                  * For each tmpl before that, find corresponding xfrm.
2491                  * Order is _important_. Later we will implement
2492                  * some barriers, but at the moment barriers
2493                  * are implied between each two transformations.
2494                  */
2495                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2496                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2497                         if (k < 0) {
2498                                 if (k < -1)
2499                                         /* "-2 - errored_index" returned */
2500                                         xerr_idx = -(2+k);
2501                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2502                                 goto reject;
2503                         }
2504                 }
2505
2506                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2507                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2508                         goto reject;
2509                 }
2510
2511                 xfrm_pols_put(pols, npols);
2512                 return 1;
2513         }
2514         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2515
2516 reject:
2517         xfrm_secpath_reject(xerr_idx, skb, &fl);
2518 reject_error:
2519         xfrm_pols_put(pols, npols);
2520         return 0;
2521 }
2522 EXPORT_SYMBOL(__xfrm_policy_check);
2523
2524 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2525 {
2526         struct net *net = dev_net(skb->dev);
2527         struct flowi fl;
2528         struct dst_entry *dst;
2529         int res = 1;
2530
2531         if (xfrm_decode_session(skb, &fl, family) < 0) {
2532                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2533                 return 0;
2534         }
2535
2536         skb_dst_force(skb);
2537
2538         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
2539         if (IS_ERR(dst)) {
2540                 res = 0;
2541                 dst = NULL;
2542         }
2543         skb_dst_set(skb, dst);
2544         return res;
2545 }
2546 EXPORT_SYMBOL(__xfrm_route_forward);
2547
2548 /* Optimize later using cookies and generation ids. */
2549
2550 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2551 {
2552         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2553          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2554          * get validated by dst_ops->check on every use.  We do this
2555          * because when a normal route referenced by an XFRM dst is
2556          * obsoleted we do not go looking around for all parent
2557          * referencing XFRM dsts so that we can invalidate them.  It
2558          * is just too much work.  Instead we make the checks here on
2559          * every use.  For example:
2560          *
2561          *      XFRM dst A --> IPv4 dst X
2562          *
2563          * X is the "xdst->route" of A (X is also the "dst->path" of A
2564          * in this example).  If X is marked obsolete, "A" will not
2565          * notice.  That's what we are validating here via the
2566          * stale_bundle() check.
2567          *
2568          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
2569          * be marked on it.
2570          * This will force stale_bundle() to fail on any xdst bundle with
2571          * this dst linked in it.
2572          */
2573         if (dst->obsolete < 0 && !stale_bundle(dst))
2574                 return dst;
2575
2576         return NULL;
2577 }
2578
2579 static int stale_bundle(struct dst_entry *dst)
2580 {
2581         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2582 }
2583
2584 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2585 {
2586         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2587                 dst->dev = dev_net(dev)->loopback_dev;
2588                 dev_hold(dst->dev);
2589                 dev_put(dev);
2590         }
2591 }
2592 EXPORT_SYMBOL(xfrm_dst_ifdown);
2593
2594 static void xfrm_link_failure(struct sk_buff *skb)
2595 {
2596         /* Impossible. Such dst must be popped before reaches point of failure. */
2597 }
2598
2599 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2600 {
2601         if (dst) {
2602                 if (dst->obsolete) {
2603                         dst_release(dst);
2604                         dst = NULL;
2605                 }
2606         }
2607         return dst;
2608 }
2609
2610 static void xfrm_init_pmtu(struct dst_entry *dst)
2611 {
2612         do {
2613                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2614                 u32 pmtu, route_mtu_cached;
2615
2616                 pmtu = dst_mtu(dst->child);
2617                 xdst->child_mtu_cached = pmtu;
2618
2619                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2620
2621                 route_mtu_cached = dst_mtu(xdst->route);
2622                 xdst->route_mtu_cached = route_mtu_cached;
2623
2624                 if (pmtu > route_mtu_cached)
2625                         pmtu = route_mtu_cached;
2626
2627                 dst_metric_set(dst, RTAX_MTU, pmtu);
2628         } while ((dst = dst->next));
2629 }
2630
2631 /* Check that the bundle accepts the flow and its components are
2632  * still valid.
2633  */
2634
2635 static int xfrm_bundle_ok(struct xfrm_dst *first)
2636 {
2637         struct dst_entry *dst = &first->u.dst;
2638         struct xfrm_dst *last;
2639         u32 mtu;
2640
2641         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2642             (dst->dev && !netif_running(dst->dev)))
2643                 return 0;
2644
2645         if (dst->flags & DST_XFRM_QUEUE)
2646                 return 1;
2647
2648         last = NULL;
2649
2650         do {
2651                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2652
2653                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2654                         return 0;
2655                 if (xdst->xfrm_genid != dst->xfrm->genid)
2656                         return 0;
2657                 if (xdst->num_pols > 0 &&
2658                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2659                         return 0;
2660
2661                 mtu = dst_mtu(dst->child);
2662                 if (xdst->child_mtu_cached != mtu) {
2663                         last = xdst;
2664                         xdst->child_mtu_cached = mtu;
2665                 }
2666
2667                 if (!dst_check(xdst->route, xdst->route_cookie))
2668                         return 0;
2669                 mtu = dst_mtu(xdst->route);
2670                 if (xdst->route_mtu_cached != mtu) {
2671                         last = xdst;
2672                         xdst->route_mtu_cached = mtu;
2673                 }
2674
2675                 dst = dst->child;
2676         } while (dst->xfrm);
2677
2678         if (likely(!last))
2679                 return 1;
2680
2681         mtu = last->child_mtu_cached;
2682         for (;;) {
2683                 dst = &last->u.dst;
2684
2685                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2686                 if (mtu > last->route_mtu_cached)
2687                         mtu = last->route_mtu_cached;
2688                 dst_metric_set(dst, RTAX_MTU, mtu);
2689
2690                 if (last == first)
2691                         break;
2692
2693                 last = (struct xfrm_dst *)last->u.dst.next;
2694                 last->child_mtu_cached = mtu;
2695         }
2696
2697         return 1;
2698 }
2699
2700 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2701 {
2702         return dst_metric_advmss(dst->path);
2703 }
2704
2705 static unsigned int xfrm_mtu(const struct dst_entry *dst)
2706 {
2707         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2708
2709         return mtu ? : dst_mtu(dst->path);
2710 }
2711
2712 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
2713                                         const void *daddr)
2714 {
2715         const struct dst_entry *path = dst->path;
2716
2717         for (; dst != path; dst = dst->child) {
2718                 const struct xfrm_state *xfrm = dst->xfrm;
2719
2720                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
2721                         continue;
2722                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
2723                         daddr = xfrm->coaddr;
2724                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
2725                         daddr = &xfrm->id.daddr;
2726         }
2727         return daddr;
2728 }
2729
2730 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2731                                            struct sk_buff *skb,
2732                                            const void *daddr)
2733 {
2734         const struct dst_entry *path = dst->path;
2735
2736         if (!skb)
2737                 daddr = xfrm_get_dst_nexthop(dst, daddr);
2738         return path->ops->neigh_lookup(path, skb, daddr);
2739 }
2740
2741 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
2742 {
2743         const struct dst_entry *path = dst->path;
2744
2745         daddr = xfrm_get_dst_nexthop(dst, daddr);
2746         path->ops->confirm_neigh(path, daddr);
2747 }
2748
2749 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
2750 {
2751         int err = 0;
2752
2753         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
2754                 return -EAFNOSUPPORT;
2755
2756         spin_lock(&xfrm_policy_afinfo_lock);
2757         if (unlikely(xfrm_policy_afinfo[family] != NULL))
2758                 err = -EEXIST;
2759         else {
2760                 struct dst_ops *dst_ops = afinfo->dst_ops;
2761                 if (likely(dst_ops->kmem_cachep == NULL))
2762                         dst_ops->kmem_cachep = xfrm_dst_cache;
2763                 if (likely(dst_ops->check == NULL))
2764                         dst_ops->check = xfrm_dst_check;
2765                 if (likely(dst_ops->default_advmss == NULL))
2766                         dst_ops->default_advmss = xfrm_default_advmss;
2767                 if (likely(dst_ops->mtu == NULL))
2768                         dst_ops->mtu = xfrm_mtu;
2769                 if (likely(dst_ops->negative_advice == NULL))
2770                         dst_ops->negative_advice = xfrm_negative_advice;
2771                 if (likely(dst_ops->link_failure == NULL))
2772                         dst_ops->link_failure = xfrm_link_failure;
2773                 if (likely(dst_ops->neigh_lookup == NULL))
2774                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
2775                 if (likely(!dst_ops->confirm_neigh))
2776                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
2777                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
2778         }
2779         spin_unlock(&xfrm_policy_afinfo_lock);
2780
2781         return err;
2782 }
2783 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2784
2785 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
2786 {
2787         struct dst_ops *dst_ops = afinfo->dst_ops;
2788         int i;
2789
2790         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
2791                 if (xfrm_policy_afinfo[i] != afinfo)
2792                         continue;
2793                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
2794                 break;
2795         }
2796
2797         synchronize_rcu();
2798
2799         dst_ops->kmem_cachep = NULL;
2800         dst_ops->check = NULL;
2801         dst_ops->negative_advice = NULL;
2802         dst_ops->link_failure = NULL;
2803 }
2804 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2805
2806 #ifdef CONFIG_XFRM_STATISTICS
2807 static int __net_init xfrm_statistics_init(struct net *net)
2808 {
2809         int rv;
2810         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
2811         if (!net->mib.xfrm_statistics)
2812                 return -ENOMEM;
2813         rv = xfrm_proc_init(net);
2814         if (rv < 0)
2815                 free_percpu(net->mib.xfrm_statistics);
2816         return rv;
2817 }
2818
2819 static void xfrm_statistics_fini(struct net *net)
2820 {
2821         xfrm_proc_fini(net);
2822         free_percpu(net->mib.xfrm_statistics);
2823 }
2824 #else
2825 static int __net_init xfrm_statistics_init(struct net *net)
2826 {
2827         return 0;
2828 }
2829
2830 static void xfrm_statistics_fini(struct net *net)
2831 {
2832 }
2833 #endif
2834
2835 static int __net_init xfrm_policy_init(struct net *net)
2836 {
2837         unsigned int hmask, sz;
2838         int dir;
2839
2840         if (net_eq(net, &init_net))
2841                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2842                                            sizeof(struct xfrm_dst),
2843                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2844                                            NULL);
2845
2846         hmask = 8 - 1;
2847         sz = (hmask+1) * sizeof(struct hlist_head);
2848
2849         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2850         if (!net->xfrm.policy_byidx)
2851                 goto out_byidx;
2852         net->xfrm.policy_idx_hmask = hmask;
2853
2854         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2855                 struct xfrm_policy_hash *htab;
2856
2857                 net->xfrm.policy_count[dir] = 0;
2858                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
2859                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2860
2861                 htab = &net->xfrm.policy_bydst[dir];
2862                 htab->table = xfrm_hash_alloc(sz);
2863                 if (!htab->table)
2864                         goto out_bydst;
2865                 htab->hmask = hmask;
2866                 htab->dbits4 = 32;
2867                 htab->sbits4 = 32;
2868                 htab->dbits6 = 128;
2869                 htab->sbits6 = 128;
2870         }
2871         net->xfrm.policy_hthresh.lbits4 = 32;
2872         net->xfrm.policy_hthresh.rbits4 = 32;
2873         net->xfrm.policy_hthresh.lbits6 = 128;
2874         net->xfrm.policy_hthresh.rbits6 = 128;
2875
2876         seqlock_init(&net->xfrm.policy_hthresh.lock);
2877
2878         INIT_LIST_HEAD(&net->xfrm.policy_all);
2879         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2880         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
2881         if (net_eq(net, &init_net))
2882                 xfrm_dev_init();
2883         return 0;
2884
2885 out_bydst:
2886         for (dir--; dir >= 0; dir--) {
2887                 struct xfrm_policy_hash *htab;
2888
2889                 htab = &net->xfrm.policy_bydst[dir];
2890                 xfrm_hash_free(htab->table, sz);
2891         }
2892         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2893 out_byidx:
2894         return -ENOMEM;
2895 }
2896
2897 static void xfrm_policy_fini(struct net *net)
2898 {
2899         unsigned int sz;
2900         int dir;
2901
2902         flush_work(&net->xfrm.policy_hash_work);
2903 #ifdef CONFIG_XFRM_SUB_POLICY
2904         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
2905 #endif
2906         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
2907
2908         WARN_ON(!list_empty(&net->xfrm.policy_all));
2909
2910         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
2911                 struct xfrm_policy_hash *htab;
2912
2913                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2914
2915                 htab = &net->xfrm.policy_bydst[dir];
2916                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
2917                 WARN_ON(!hlist_empty(htab->table));
2918                 xfrm_hash_free(htab->table, sz);
2919         }
2920
2921         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2922         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2923         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2924 }
2925
2926 static int __net_init xfrm_net_init(struct net *net)
2927 {
2928         int rv;
2929
2930         /* Initialize the per-net locks here */
2931         spin_lock_init(&net->xfrm.xfrm_state_lock);
2932         spin_lock_init(&net->xfrm.xfrm_policy_lock);
2933         mutex_init(&net->xfrm.xfrm_cfg_mutex);
2934
2935         rv = xfrm_statistics_init(net);
2936         if (rv < 0)
2937                 goto out_statistics;
2938         rv = xfrm_state_init(net);
2939         if (rv < 0)
2940                 goto out_state;
2941         rv = xfrm_policy_init(net);
2942         if (rv < 0)
2943                 goto out_policy;
2944         rv = xfrm_sysctl_init(net);
2945         if (rv < 0)
2946                 goto out_sysctl;
2947
2948         return 0;
2949
2950 out_sysctl:
2951         xfrm_policy_fini(net);
2952 out_policy:
2953         xfrm_state_fini(net);
2954 out_state:
2955         xfrm_statistics_fini(net);
2956 out_statistics:
2957         return rv;
2958 }
2959
2960 static void __net_exit xfrm_net_exit(struct net *net)
2961 {
2962         xfrm_sysctl_fini(net);
2963         xfrm_policy_fini(net);
2964         xfrm_state_fini(net);
2965         xfrm_statistics_fini(net);
2966 }
2967
2968 static struct pernet_operations __net_initdata xfrm_net_ops = {
2969         .init = xfrm_net_init,
2970         .exit = xfrm_net_exit,
2971 };
2972
2973 void __init xfrm_init(void)
2974 {
2975         int i;
2976
2977         xfrm_pcpu_work = kmalloc_array(NR_CPUS, sizeof(*xfrm_pcpu_work),
2978                                        GFP_KERNEL);
2979         BUG_ON(!xfrm_pcpu_work);
2980
2981         for (i = 0; i < NR_CPUS; i++)
2982                 INIT_WORK(&xfrm_pcpu_work[i], xfrm_pcpu_work_fn);
2983
2984         register_pernet_subsys(&xfrm_net_ops);
2985         seqcount_init(&xfrm_policy_hash_generation);
2986         xfrm_input_init();
2987 }
2988
2989 #ifdef CONFIG_AUDITSYSCALL
2990 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2991                                          struct audit_buffer *audit_buf)
2992 {
2993         struct xfrm_sec_ctx *ctx = xp->security;
2994         struct xfrm_selector *sel = &xp->selector;
2995
2996         if (ctx)
2997                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2998                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2999
3000         switch (sel->family) {
3001         case AF_INET:
3002                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
3003                 if (sel->prefixlen_s != 32)
3004                         audit_log_format(audit_buf, " src_prefixlen=%d",
3005                                          sel->prefixlen_s);
3006                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
3007                 if (sel->prefixlen_d != 32)
3008                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3009                                          sel->prefixlen_d);
3010                 break;
3011         case AF_INET6:
3012                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
3013                 if (sel->prefixlen_s != 128)
3014                         audit_log_format(audit_buf, " src_prefixlen=%d",
3015                                          sel->prefixlen_s);
3016                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
3017                 if (sel->prefixlen_d != 128)
3018                         audit_log_format(audit_buf, " dst_prefixlen=%d",
3019                                          sel->prefixlen_d);
3020                 break;
3021         }
3022 }
3023
3024 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
3025 {
3026         struct audit_buffer *audit_buf;
3027
3028         audit_buf = xfrm_audit_start("SPD-add");
3029         if (audit_buf == NULL)
3030                 return;
3031         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3032         audit_log_format(audit_buf, " res=%u", result);
3033         xfrm_audit_common_policyinfo(xp, audit_buf);
3034         audit_log_end(audit_buf);
3035 }
3036 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
3037
3038 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
3039                               bool task_valid)
3040 {
3041         struct audit_buffer *audit_buf;
3042
3043         audit_buf = xfrm_audit_start("SPD-delete");
3044         if (audit_buf == NULL)
3045                 return;
3046         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
3047         audit_log_format(audit_buf, " res=%u", result);
3048         xfrm_audit_common_policyinfo(xp, audit_buf);
3049         audit_log_end(audit_buf);
3050 }
3051 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
3052 #endif
3053
3054 #ifdef CONFIG_XFRM_MIGRATE
3055 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
3056                                         const struct xfrm_selector *sel_tgt)
3057 {
3058         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
3059                 if (sel_tgt->family == sel_cmp->family &&
3060                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
3061                                     sel_cmp->family) &&
3062                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
3063                                     sel_cmp->family) &&
3064                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
3065                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
3066                         return true;
3067                 }
3068         } else {
3069                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
3070                         return true;
3071                 }
3072         }
3073         return false;
3074 }
3075
3076 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
3077                                                     u8 dir, u8 type, struct net *net)
3078 {
3079         struct xfrm_policy *pol, *ret = NULL;
3080         struct hlist_head *chain;
3081         u32 priority = ~0U;
3082
3083         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
3084         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
3085         hlist_for_each_entry(pol, chain, bydst) {
3086                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3087                     pol->type == type) {
3088                         ret = pol;
3089                         priority = ret->priority;
3090                         break;
3091                 }
3092         }
3093         chain = &net->xfrm.policy_inexact[dir];
3094         hlist_for_each_entry(pol, chain, bydst) {
3095                 if ((pol->priority >= priority) && ret)
3096                         break;
3097
3098                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
3099                     pol->type == type) {
3100                         ret = pol;
3101                         break;
3102                 }
3103         }
3104
3105         xfrm_pol_hold(ret);
3106
3107         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
3108
3109         return ret;
3110 }
3111
3112 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
3113 {
3114         int match = 0;
3115
3116         if (t->mode == m->mode && t->id.proto == m->proto &&
3117             (m->reqid == 0 || t->reqid == m->reqid)) {
3118                 switch (t->mode) {
3119                 case XFRM_MODE_TUNNEL:
3120                 case XFRM_MODE_BEET:
3121                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
3122                                             m->old_family) &&
3123                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
3124                                             m->old_family)) {
3125                                 match = 1;
3126                         }
3127                         break;
3128                 case XFRM_MODE_TRANSPORT:
3129                         /* in case of transport mode, template does not store
3130                            any IP addresses, hence we just compare mode and
3131                            protocol */
3132                         match = 1;
3133                         break;
3134                 default:
3135                         break;
3136                 }
3137         }
3138         return match;
3139 }
3140
3141 /* update endpoint address(es) of template(s) */
3142 static int xfrm_policy_migrate(struct xfrm_policy *pol,
3143                                struct xfrm_migrate *m, int num_migrate)
3144 {
3145         struct xfrm_migrate *mp;
3146         int i, j, n = 0;
3147
3148         write_lock_bh(&pol->lock);
3149         if (unlikely(pol->walk.dead)) {
3150                 /* target policy has been deleted */
3151                 write_unlock_bh(&pol->lock);
3152                 return -ENOENT;
3153         }
3154
3155         for (i = 0; i < pol->xfrm_nr; i++) {
3156                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
3157                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
3158                                 continue;
3159                         n++;
3160                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
3161                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
3162                                 continue;
3163                         /* update endpoints */
3164                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
3165                                sizeof(pol->xfrm_vec[i].id.daddr));
3166                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
3167                                sizeof(pol->xfrm_vec[i].saddr));
3168                         pol->xfrm_vec[i].encap_family = mp->new_family;
3169                         /* flush bundles */
3170                         atomic_inc(&pol->genid);
3171                 }
3172         }
3173
3174         write_unlock_bh(&pol->lock);
3175
3176         if (!n)
3177                 return -ENODATA;
3178
3179         return 0;
3180 }
3181
3182 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
3183 {
3184         int i, j;
3185
3186         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
3187                 return -EINVAL;
3188
3189         for (i = 0; i < num_migrate; i++) {
3190                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
3191                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
3192                         return -EINVAL;
3193
3194                 /* check if there is any duplicated entry */
3195                 for (j = i + 1; j < num_migrate; j++) {
3196                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
3197                                     sizeof(m[i].old_daddr)) &&
3198                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
3199                                     sizeof(m[i].old_saddr)) &&
3200                             m[i].proto == m[j].proto &&
3201                             m[i].mode == m[j].mode &&
3202                             m[i].reqid == m[j].reqid &&
3203                             m[i].old_family == m[j].old_family)
3204                                 return -EINVAL;
3205                 }
3206         }
3207
3208         return 0;
3209 }
3210
3211 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
3212                  struct xfrm_migrate *m, int num_migrate,
3213                  struct xfrm_kmaddress *k, struct net *net,
3214                  struct xfrm_encap_tmpl *encap)
3215 {
3216         int i, err, nx_cur = 0, nx_new = 0;
3217         struct xfrm_policy *pol = NULL;
3218         struct xfrm_state *x, *xc;
3219         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
3220         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
3221         struct xfrm_migrate *mp;
3222
3223         /* Stage 0 - sanity checks */
3224         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
3225                 goto out;
3226
3227         if (dir >= XFRM_POLICY_MAX) {
3228                 err = -EINVAL;
3229                 goto out;
3230         }
3231
3232         /* Stage 1 - find policy */
3233         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
3234                 err = -ENOENT;
3235                 goto out;
3236         }
3237
3238         /* Stage 2 - find and update state(s) */
3239         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
3240                 if ((x = xfrm_migrate_state_find(mp, net))) {
3241                         x_cur[nx_cur] = x;
3242                         nx_cur++;
3243                         xc = xfrm_state_migrate(x, mp, encap);
3244                         if (xc) {
3245                                 x_new[nx_new] = xc;
3246                                 nx_new++;
3247                         } else {
3248                                 err = -ENODATA;
3249                                 goto restore_state;
3250                         }
3251                 }
3252         }
3253
3254         /* Stage 3 - update policy */
3255         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
3256                 goto restore_state;
3257
3258         /* Stage 4 - delete old state(s) */
3259         if (nx_cur) {
3260                 xfrm_states_put(x_cur, nx_cur);
3261                 xfrm_states_delete(x_cur, nx_cur);
3262         }
3263
3264         /* Stage 5 - announce */
3265         km_migrate(sel, dir, type, m, num_migrate, k, encap);
3266
3267         xfrm_pol_put(pol);
3268
3269         return 0;
3270 out:
3271         return err;
3272
3273 restore_state:
3274         if (pol)
3275                 xfrm_pol_put(pol);
3276         if (nx_cur)
3277                 xfrm_states_put(x_cur, nx_cur);
3278         if (nx_new)
3279                 xfrm_states_delete(x_new, nx_new);
3280
3281         return err;
3282 }
3283 EXPORT_SYMBOL(xfrm_migrate);
3284 #endif