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   1 /*
   2  * xfrm_policy.c
   3  *
   4  * Changes:
   5  *      Mitsuru KANDA @USAGI
   6  *      Kazunori MIYAZAWA @USAGI
   7  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   8  *              IPv6 support
   9  *      Kazunori MIYAZAWA @USAGI
  10  *      YOSHIFUJI Hideaki
  11  *              Split up af-specific portion
  12  *      Derek Atkins <derek@ihtfp.com>          Add the post_input processor
  13  *
  14  */
  15
  16 #include <linux/err.h>
  17 #include <linux/slab.h>
  18 #include <linux/kmod.h>
  19 #include <linux/list.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/notifier.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/netfilter.h>
  25 #include <linux/module.h>
  26 #include <linux/cache.h>
  27 #include <linux/audit.h>
  28 #include <net/dst.h>
  29 #include <net/xfrm.h>
  30 #include <net/ip.h>
  31 #ifdef CONFIG_XFRM_STATISTICS
  32 #include <net/snmp.h>
  33 #endif
  34
  35 #include "xfrm_hash.h"
  36
  37 DEFINE_MUTEX(xfrm_cfg_mutex);
  38 EXPORT_SYMBOL(xfrm_cfg_mutex);
  39
  40 static DEFINE_RWLOCK(xfrm_policy_lock);
  41
  42 static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
  43 static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
  44
  45 static struct kmem_cache *xfrm_dst_cache __read_mostly;
  46
  47 static HLIST_HEAD(xfrm_policy_gc_list);
  48 static DEFINE_SPINLOCK(xfrm_policy_gc_lock);
  49
  50 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
  51 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
  52 static void xfrm_init_pmtu(struct dst_entry *dst);
  53
  54 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
  55                                                 int dir);
  56
  57 static inline int
  58 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
  59 {
  60         return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
  61                 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
  62                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
  63                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
  64                 (fl->proto == sel->proto || !sel->proto) &&
  65                 (fl->oif == sel->ifindex || !sel->ifindex);
  66 }
  67
  68 static inline int
  69 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
  70 {
  71         return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
  72                 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
  73                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
  74                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
  75                 (fl->proto == sel->proto || !sel->proto) &&
  76                 (fl->oif == sel->ifindex || !sel->ifindex);
  77 }
  78
  79 int xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
  80                     unsigned short family)
  81 {
  82         switch (family) {
  83         case AF_INET:
  84                 return __xfrm4_selector_match(sel, fl);
  85         case AF_INET6:
  86                 return __xfrm6_selector_match(sel, fl);
  87         }
  88         return 0;
  89 }
  90
  91 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
  92                                                   xfrm_address_t *saddr,
  93                                                   xfrm_address_t *daddr,
  94                                                   int family)
  95 {
  96         struct xfrm_policy_afinfo *afinfo;
  97         struct dst_entry *dst;
  98
  99         afinfo = xfrm_policy_get_afinfo(family);
 100         if (unlikely(afinfo == NULL))
 101                 return ERR_PTR(-EAFNOSUPPORT);
 102
 103         dst = afinfo->dst_lookup(net, tos, saddr, daddr);
 104
 105         xfrm_policy_put_afinfo(afinfo);
 106
 107         return dst;
 108 }
 109
 110 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
 111                                                 xfrm_address_t *prev_saddr,
 112                                                 xfrm_address_t *prev_daddr,
 113                                                 int family)
 114 {
 115         struct net *net = xs_net(x);
 116         xfrm_address_t *saddr = &x->props.saddr;
 117         xfrm_address_t *daddr = &x->id.daddr;
 118         struct dst_entry *dst;
 119
 120         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 121                 saddr = x->coaddr;
 122                 daddr = prev_daddr;
 123         }
 124         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 125                 saddr = prev_saddr;
 126                 daddr = x->coaddr;
 127         }
 128
 129         dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
 130
 131         if (!IS_ERR(dst)) {
 132                 if (prev_saddr != saddr)
 133                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 134                 if (prev_daddr != daddr)
 135                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 136         }
 137
 138         return dst;
 139 }
 140
 141 static inline unsigned long make_jiffies(long secs)
 142 {
 143         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 144                 return MAX_SCHEDULE_TIMEOUT-1;
 145         else
 146                 return secs*HZ;
 147 }
 148
 149 static void xfrm_policy_timer(unsigned long data)
 150 {
 151         struct xfrm_policy *xp = (struct xfrm_policy*)data;
 152         unsigned long now = get_seconds();
 153         long next = LONG_MAX;
 154         int warn = 0;
 155         int dir;
 156
 157         read_lock(&xp->lock);
 158
 159         if (xp->walk.dead)
 160                 goto out;
 161
 162         dir = xfrm_policy_id2dir(xp->index);
 163
 164         if (xp->lft.hard_add_expires_seconds) {
 165                 long tmo = xp->lft.hard_add_expires_seconds +
 166                         xp->curlft.add_time - now;
 167                 if (tmo <= 0)
 168                         goto expired;
 169                 if (tmo < next)
 170                         next = tmo;
 171         }
 172         if (xp->lft.hard_use_expires_seconds) {
 173                 long tmo = xp->lft.hard_use_expires_seconds +
 174                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 175                 if (tmo <= 0)
 176                         goto expired;
 177                 if (tmo < next)
 178                         next = tmo;
 179         }
 180         if (xp->lft.soft_add_expires_seconds) {
 181                 long tmo = xp->lft.soft_add_expires_seconds +
 182                         xp->curlft.add_time - now;
 183                 if (tmo <= 0) {
 184                         warn = 1;
 185                         tmo = XFRM_KM_TIMEOUT;
 186                 }
 187                 if (tmo < next)
 188                         next = tmo;
 189         }
 190         if (xp->lft.soft_use_expires_seconds) {
 191                 long tmo = xp->lft.soft_use_expires_seconds +
 192                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 193                 if (tmo <= 0) {
 194                         warn = 1;
 195                         tmo = XFRM_KM_TIMEOUT;
 196                 }
 197                 if (tmo < next)
 198                         next = tmo;
 199         }
 200
 201         if (warn)
 202                 km_policy_expired(xp, dir, 0, 0);
 203         if (next != LONG_MAX &&
 204             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 205                 xfrm_pol_hold(xp);
 206
 207 out:
 208         read_unlock(&xp->lock);
 209         xfrm_pol_put(xp);
 210         return;
 211
 212 expired:
 213         read_unlock(&xp->lock);
 214         if (!xfrm_policy_delete(xp, dir))
 215                 km_policy_expired(xp, dir, 1, 0);
 216         xfrm_pol_put(xp);
 217 }
 218
 219
 220 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 221  * SPD calls.
 222  */
 223
 224 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 225 {
 226         struct xfrm_policy *policy;
 227
 228         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 229
 230         if (policy) {
 231                 write_pnet(&policy->xp_net, net);
 232                 INIT_LIST_HEAD(&policy->walk.all);
 233                 INIT_HLIST_NODE(&policy->bydst);
 234                 INIT_HLIST_NODE(&policy->byidx);
 235                 rwlock_init(&policy->lock);
 236                 atomic_set(&policy->refcnt, 1);
 237                 setup_timer(&policy->timer, xfrm_policy_timer,
 238                                 (unsigned long)policy);
 239         }
 240         return policy;
 241 }
 242 EXPORT_SYMBOL(xfrm_policy_alloc);
 243
 244 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 245
 246 void xfrm_policy_destroy(struct xfrm_policy *policy)
 247 {
 248         BUG_ON(!policy->walk.dead);
 249
 250         BUG_ON(policy->bundles);
 251
 252         if (del_timer(&policy->timer))
 253                 BUG();
 254
 255         security_xfrm_policy_free(policy->security);
 256         kfree(policy);
 257 }
 258 EXPORT_SYMBOL(xfrm_policy_destroy);
 259
 260 static void xfrm_policy_gc_kill(struct xfrm_policy *policy)
 261 {
 262         struct dst_entry *dst;
 263
 264         while ((dst = policy->bundles) != NULL) {
 265                 policy->bundles = dst->next;
 266                 dst_free(dst);
 267         }
 268
 269         if (del_timer(&policy->timer))
 270                 atomic_dec(&policy->refcnt);
 271
 272         if (atomic_read(&policy->refcnt) > 1)
 273                 flow_cache_flush();
 274
 275         xfrm_pol_put(policy);
 276 }
 277
 278 static void xfrm_policy_gc_task(struct work_struct *work)
 279 {
 280         struct xfrm_policy *policy;
 281         struct hlist_node *entry, *tmp;
 282         struct hlist_head gc_list;
 283
 284         spin_lock_bh(&xfrm_policy_gc_lock);
 285         gc_list.first = xfrm_policy_gc_list.first;
 286         INIT_HLIST_HEAD(&xfrm_policy_gc_list);
 287         spin_unlock_bh(&xfrm_policy_gc_lock);
 288
 289         hlist_for_each_entry_safe(policy, entry, tmp, &gc_list, bydst)
 290                 xfrm_policy_gc_kill(policy);
 291 }
 292 static DECLARE_WORK(xfrm_policy_gc_work, xfrm_policy_gc_task);
 293
 294 /* Rule must be locked. Release descentant resources, announce
 295  * entry dead. The rule must be unlinked from lists to the moment.
 296  */
 297
 298 static void xfrm_policy_kill(struct xfrm_policy *policy)
 299 {
 300         int dead;
 301
 302         write_lock_bh(&policy->lock);
 303         dead = policy->walk.dead;
 304         policy->walk.dead = 1;
 305         write_unlock_bh(&policy->lock);
 306
 307         if (unlikely(dead)) {
 308                 WARN_ON(1);
 309                 return;
 310         }
 311
 312         spin_lock_bh(&xfrm_policy_gc_lock);
 313         hlist_add_head(&policy->bydst, &xfrm_policy_gc_list);
 314         spin_unlock_bh(&xfrm_policy_gc_lock);
 315
 316         schedule_work(&xfrm_policy_gc_work);
 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 static struct hlist_head *policy_hash_bysel(struct net *net, struct xfrm_selector *sel, unsigned short family, int dir)
 327 {
 328         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 329         unsigned int hash = __sel_hash(sel, family, hmask);
 330
 331         return (hash == hmask + 1 ?
 332                 &net->xfrm.policy_inexact[dir] :
 333                 net->xfrm.policy_bydst[dir].table + hash);
 334 }
 335
 336 static struct hlist_head *policy_hash_direct(struct net *net, xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, int dir)
 337 {
 338         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 339         unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
 340
 341         return net->xfrm.policy_bydst[dir].table + hash;
 342 }
 343
 344 static void xfrm_dst_hash_transfer(struct hlist_head *list,
 345                                    struct hlist_head *ndsttable,
 346                                    unsigned int nhashmask)
 347 {
 348         struct hlist_node *entry, *tmp, *entry0 = NULL;
 349         struct xfrm_policy *pol;
 350         unsigned int h0 = 0;
 351
 352 redo:
 353         hlist_for_each_entry_safe(pol, entry, tmp, list, bydst) {
 354                 unsigned int h;
 355
 356                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 357                                 pol->family, nhashmask);
 358                 if (!entry0) {
 359                         hlist_del(entry);
 360                         hlist_add_head(&pol->bydst, ndsttable+h);
 361                         h0 = h;
 362                 } else {
 363                         if (h != h0)
 364                                 continue;
 365                         hlist_del(entry);
 366                         hlist_add_after(entry0, &pol->bydst);
 367                 }
 368                 entry0 = entry;
 369         }
 370         if (!hlist_empty(list)) {
 371                 entry0 = NULL;
 372                 goto redo;
 373         }
 374 }
 375
 376 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 377                                    struct hlist_head *nidxtable,
 378                                    unsigned int nhashmask)
 379 {
 380         struct hlist_node *entry, *tmp;
 381         struct xfrm_policy *pol;
 382
 383         hlist_for_each_entry_safe(pol, entry, tmp, list, byidx) {
 384                 unsigned int h;
 385
 386                 h = __idx_hash(pol->index, nhashmask);
 387                 hlist_add_head(&pol->byidx, nidxtable+h);
 388         }
 389 }
 390
 391 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 392 {
 393         return ((old_hmask + 1) << 1) - 1;
 394 }
 395
 396 static void xfrm_bydst_resize(struct net *net, int dir)
 397 {
 398         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 399         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 400         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 401         struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
 402         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 403         int i;
 404
 405         if (!ndst)
 406                 return;
 407
 408         write_lock_bh(&xfrm_policy_lock);
 409
 410         for (i = hmask; i >= 0; i--)
 411                 xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
 412
 413         net->xfrm.policy_bydst[dir].table = ndst;
 414         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 415
 416         write_unlock_bh(&xfrm_policy_lock);
 417
 418         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 419 }
 420
 421 static void xfrm_byidx_resize(struct net *net, int total)
 422 {
 423         unsigned int hmask = net->xfrm.policy_idx_hmask;
 424         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 425         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 426         struct hlist_head *oidx = net->xfrm.policy_byidx;
 427         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 428         int i;
 429
 430         if (!nidx)
 431                 return;
 432
 433         write_lock_bh(&xfrm_policy_lock);
 434
 435         for (i = hmask; i >= 0; i--)
 436                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 437
 438         net->xfrm.policy_byidx = nidx;
 439         net->xfrm.policy_idx_hmask = nhashmask;
 440
 441         write_unlock_bh(&xfrm_policy_lock);
 442
 443         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 444 }
 445
 446 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 447 {
 448         unsigned int cnt = net->xfrm.policy_count[dir];
 449         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 450
 451         if (total)
 452                 *total += cnt;
 453
 454         if ((hmask + 1) < xfrm_policy_hashmax &&
 455             cnt > hmask)
 456                 return 1;
 457
 458         return 0;
 459 }
 460
 461 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 462 {
 463         unsigned int hmask = net->xfrm.policy_idx_hmask;
 464
 465         if ((hmask + 1) < xfrm_policy_hashmax &&
 466             total > hmask)
 467                 return 1;
 468
 469         return 0;
 470 }
 471
 472 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 473 {
 474         read_lock_bh(&xfrm_policy_lock);
 475         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 476         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 477         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 478         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 479         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 480         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 481         si->spdhcnt = net->xfrm.policy_idx_hmask;
 482         si->spdhmcnt = xfrm_policy_hashmax;
 483         read_unlock_bh(&xfrm_policy_lock);
 484 }
 485 EXPORT_SYMBOL(xfrm_spd_getinfo);
 486
 487 static DEFINE_MUTEX(hash_resize_mutex);
 488 static void xfrm_hash_resize(struct work_struct *work)
 489 {
 490         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 491         int dir, total;
 492
 493         mutex_lock(&hash_resize_mutex);
 494
 495         total = 0;
 496         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
 497                 if (xfrm_bydst_should_resize(net, dir, &total))
 498                         xfrm_bydst_resize(net, dir);
 499         }
 500         if (xfrm_byidx_should_resize(net, total))
 501                 xfrm_byidx_resize(net, total);
 502
 503         mutex_unlock(&hash_resize_mutex);
 504 }
 505
 506 /* Generate new index... KAME seems to generate them ordered by cost
 507  * of an absolute inpredictability of ordering of rules. This will not pass. */
 508 static u32 xfrm_gen_index(struct net *net, int dir)
 509 {
 510         static u32 idx_generator;
 511
 512         for (;;) {
 513                 struct hlist_node *entry;
 514                 struct hlist_head *list;
 515                 struct xfrm_policy *p;
 516                 u32 idx;
 517                 int found;
 518
 519                 idx = (idx_generator | dir);
 520                 idx_generator += 8;
 521                 if (idx == 0)
 522                         idx = 8;
 523                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
 524                 found = 0;
 525                 hlist_for_each_entry(p, entry, list, byidx) {
 526                         if (p->index == idx) {
 527                                 found = 1;
 528                                 break;
 529                         }
 530                 }
 531                 if (!found)
 532                         return idx;
 533         }
 534 }
 535
 536 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 537 {
 538         u32 *p1 = (u32 *) s1;
 539         u32 *p2 = (u32 *) s2;
 540         int len = sizeof(struct xfrm_selector) / sizeof(u32);
 541         int i;
 542
 543         for (i = 0; i < len; i++) {
 544                 if (p1[i] != p2[i])
 545                         return 1;
 546         }
 547
 548         return 0;
 549 }
 550
 551 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 552 {
 553         struct net *net = xp_net(policy);
 554         struct xfrm_policy *pol;
 555         struct xfrm_policy *delpol;
 556         struct hlist_head *chain;
 557         struct hlist_node *entry, *newpos;
 558         struct dst_entry *gc_list;
 559
 560         write_lock_bh(&xfrm_policy_lock);
 561         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 562         delpol = NULL;
 563         newpos = NULL;
 564         hlist_for_each_entry(pol, entry, chain, bydst) {
 565                 if (pol->type == policy->type &&
 566                     !selector_cmp(&pol->selector, &policy->selector) &&
 567                     xfrm_sec_ctx_match(pol->security, policy->security) &&
 568                     !WARN_ON(delpol)) {
 569                         if (excl) {
 570                                 write_unlock_bh(&xfrm_policy_lock);
 571                                 return -EEXIST;
 572                         }
 573                         delpol = pol;
 574                         if (policy->priority > pol->priority)
 575                                 continue;
 576                 } else if (policy->priority >= pol->priority) {
 577                         newpos = &pol->bydst;
 578                         continue;
 579                 }
 580                 if (delpol)
 581                         break;
 582         }
 583         if (newpos)
 584                 hlist_add_after(newpos, &policy->bydst);
 585         else
 586                 hlist_add_head(&policy->bydst, chain);
 587         xfrm_pol_hold(policy);
 588         net->xfrm.policy_count[dir]++;
 589         atomic_inc(&flow_cache_genid);
 590         if (delpol)
 591                 __xfrm_policy_unlink(delpol, dir);
 592         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir);
 593         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 594         policy->curlft.add_time = get_seconds();
 595         policy->curlft.use_time = 0;
 596         if (!mod_timer(&policy->timer, jiffies + HZ))
 597                 xfrm_pol_hold(policy);
 598         list_add(&policy->walk.all, &net->xfrm.policy_all);
 599         write_unlock_bh(&xfrm_policy_lock);
 600
 601         if (delpol)
 602                 xfrm_policy_kill(delpol);
 603         else if (xfrm_bydst_should_resize(net, dir, NULL))
 604                 schedule_work(&net->xfrm.policy_hash_work);
 605
 606         read_lock_bh(&xfrm_policy_lock);
 607         gc_list = NULL;
 608         entry = &policy->bydst;
 609         hlist_for_each_entry_continue(policy, entry, bydst) {
 610                 struct dst_entry *dst;
 611
 612                 write_lock(&policy->lock);
 613                 dst = policy->bundles;
 614                 if (dst) {
 615                         struct dst_entry *tail = dst;
 616                         while (tail->next)
 617                                 tail = tail->next;
 618                         tail->next = gc_list;
 619                         gc_list = dst;
 620
 621                         policy->bundles = NULL;
 622                 }
 623                 write_unlock(&policy->lock);
 624         }
 625         read_unlock_bh(&xfrm_policy_lock);
 626
 627         while (gc_list) {
 628                 struct dst_entry *dst = gc_list;
 629
 630                 gc_list = dst->next;
 631                 dst_free(dst);
 632         }
 633
 634         return 0;
 635 }
 636 EXPORT_SYMBOL(xfrm_policy_insert);
 637
 638 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u8 type, int dir,
 639                                           struct xfrm_selector *sel,
 640                                           struct xfrm_sec_ctx *ctx, int delete,
 641                                           int *err)
 642 {
 643         struct xfrm_policy *pol, *ret;
 644         struct hlist_head *chain;
 645         struct hlist_node *entry;
 646
 647         *err = 0;
 648         write_lock_bh(&xfrm_policy_lock);
 649         chain = policy_hash_bysel(net, sel, sel->family, dir);
 650         ret = NULL;
 651         hlist_for_each_entry(pol, entry, chain, bydst) {
 652                 if (pol->type == type &&
 653                     !selector_cmp(sel, &pol->selector) &&
 654                     xfrm_sec_ctx_match(ctx, pol->security)) {
 655                         xfrm_pol_hold(pol);
 656                         if (delete) {
 657                                 *err = security_xfrm_policy_delete(
 658                                                                 pol->security);
 659                                 if (*err) {
 660                                         write_unlock_bh(&xfrm_policy_lock);
 661                                         return pol;
 662                                 }
 663                                 __xfrm_policy_unlink(pol, dir);
 664                         }
 665                         ret = pol;
 666                         break;
 667                 }
 668         }
 669         write_unlock_bh(&xfrm_policy_lock);
 670
 671         if (ret && delete) {
 672                 atomic_inc(&flow_cache_genid);
 673                 xfrm_policy_kill(ret);
 674         }
 675         return ret;
 676 }
 677 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 678
 679 struct xfrm_policy *xfrm_policy_byid(struct net *net, u8 type, int dir, u32 id,
 680                                      int delete, int *err)
 681 {
 682         struct xfrm_policy *pol, *ret;
 683         struct hlist_head *chain;
 684         struct hlist_node *entry;
 685
 686         *err = -ENOENT;
 687         if (xfrm_policy_id2dir(id) != dir)
 688                 return NULL;
 689
 690         *err = 0;
 691         write_lock_bh(&xfrm_policy_lock);
 692         chain = net->xfrm.policy_byidx + idx_hash(net, id);
 693         ret = NULL;
 694         hlist_for_each_entry(pol, entry, chain, byidx) {
 695                 if (pol->type == type && pol->index == id) {
 696                         xfrm_pol_hold(pol);
 697                         if (delete) {
 698                                 *err = security_xfrm_policy_delete(
 699                                                                 pol->security);
 700                                 if (*err) {
 701                                         write_unlock_bh(&xfrm_policy_lock);
 702                                         return pol;
 703                                 }
 704                                 __xfrm_policy_unlink(pol, dir);
 705                         }
 706                         ret = pol;
 707                         break;
 708                 }
 709         }
 710         write_unlock_bh(&xfrm_policy_lock);
 711
 712         if (ret && delete) {
 713                 atomic_inc(&flow_cache_genid);
 714                 xfrm_policy_kill(ret);
 715         }
 716         return ret;
 717 }
 718 EXPORT_SYMBOL(xfrm_policy_byid);
 719
 720 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 721 static inline int
 722 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
 723 {
 724         int dir, err = 0;
 725
 726         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 727                 struct xfrm_policy *pol;
 728                 struct hlist_node *entry;
 729                 int i;
 730
 731                 hlist_for_each_entry(pol, entry,
 732                                      &net->xfrm.policy_inexact[dir], bydst) {
 733                         if (pol->type != type)
 734                                 continue;
 735                         err = security_xfrm_policy_delete(pol->security);
 736                         if (err) {
 737                                 xfrm_audit_policy_delete(pol, 0,
 738                                                          audit_info->loginuid,
 739                                                          audit_info->sessionid,
 740                                                          audit_info->secid);
 741                                 return err;
 742                         }
 743                 }
 744                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 745                         hlist_for_each_entry(pol, entry,
 746                                              net->xfrm.policy_bydst[dir].table + i,
 747                                              bydst) {
 748                                 if (pol->type != type)
 749                                         continue;
 750                                 err = security_xfrm_policy_delete(
 751                                                                 pol->security);
 752                                 if (err) {
 753                                         xfrm_audit_policy_delete(pol, 0,
 754                                                         audit_info->loginuid,
 755                                                         audit_info->sessionid,
 756                                                         audit_info->secid);
 757                                         return err;
 758                                 }
 759                         }
 760                 }
 761         }
 762         return err;
 763 }
 764 #else
 765 static inline int
 766 xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
 767 {
 768         return 0;
 769 }
 770 #endif
 771
 772 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info)
 773 {
 774         int dir, err = 0, cnt = 0;
 775         struct xfrm_policy *dp;
 776
 777         write_lock_bh(&xfrm_policy_lock);
 778
 779         err = xfrm_policy_flush_secctx_check(net, type, audit_info);
 780         if (err)
 781                 goto out;
 782
 783         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 784                 struct xfrm_policy *pol;
 785                 struct hlist_node *entry;
 786                 int i;
 787
 788         again1:
 789                 hlist_for_each_entry(pol, entry,
 790                                      &net->xfrm.policy_inexact[dir], bydst) {
 791                         if (pol->type != type)
 792                                 continue;
 793                         dp = __xfrm_policy_unlink(pol, dir);
 794                         write_unlock_bh(&xfrm_policy_lock);
 795                         if (dp)
 796                                 cnt++;
 797
 798                         xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
 799                                                  audit_info->sessionid,
 800                                                  audit_info->secid);
 801
 802                         xfrm_policy_kill(pol);
 803
 804                         write_lock_bh(&xfrm_policy_lock);
 805                         goto again1;
 806                 }
 807
 808                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 809         again2:
 810                         hlist_for_each_entry(pol, entry,
 811                                              net->xfrm.policy_bydst[dir].table + i,
 812                                              bydst) {
 813                                 if (pol->type != type)
 814                                         continue;
 815                                 dp = __xfrm_policy_unlink(pol, dir);
 816                                 write_unlock_bh(&xfrm_policy_lock);
 817                                 if (dp)
 818                                         cnt++;
 819
 820                                 xfrm_audit_policy_delete(pol, 1,
 821                                                          audit_info->loginuid,
 822                                                          audit_info->sessionid,
 823                                                          audit_info->secid);
 824                                 xfrm_policy_kill(pol);
 825
 826                                 write_lock_bh(&xfrm_policy_lock);
 827                                 goto again2;
 828                         }
 829                 }
 830
 831         }
 832         if (!cnt)
 833                 err = -ESRCH;
 834         atomic_inc(&flow_cache_genid);
 835 out:
 836         write_unlock_bh(&xfrm_policy_lock);
 837         return err;
 838 }
 839 EXPORT_SYMBOL(xfrm_policy_flush);
 840
 841 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 842                      int (*func)(struct xfrm_policy *, int, int, void*),
 843                      void *data)
 844 {
 845         struct xfrm_policy *pol;
 846         struct xfrm_policy_walk_entry *x;
 847         int error = 0;
 848
 849         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
 850             walk->type != XFRM_POLICY_TYPE_ANY)
 851                 return -EINVAL;
 852
 853         if (list_empty(&walk->walk.all) && walk->seq != 0)
 854                 return 0;
 855
 856         write_lock_bh(&xfrm_policy_lock);
 857         if (list_empty(&walk->walk.all))
 858                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
 859         else
 860                 x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
 861         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
 862                 if (x->dead)
 863                         continue;
 864                 pol = container_of(x, struct xfrm_policy, walk);
 865                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
 866                     walk->type != pol->type)
 867                         continue;
 868                 error = func(pol, xfrm_policy_id2dir(pol->index),
 869                              walk->seq, data);
 870                 if (error) {
 871                         list_move_tail(&walk->walk.all, &x->all);
 872                         goto out;
 873                 }
 874                 walk->seq++;
 875         }
 876         if (walk->seq == 0) {
 877                 error = -ENOENT;
 878                 goto out;
 879         }
 880         list_del_init(&walk->walk.all);
 881 out:
 882         write_unlock_bh(&xfrm_policy_lock);
 883         return error;
 884 }
 885 EXPORT_SYMBOL(xfrm_policy_walk);
 886
 887 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
 888 {
 889         INIT_LIST_HEAD(&walk->walk.all);
 890         walk->walk.dead = 1;
 891         walk->type = type;
 892         walk->seq = 0;
 893 }
 894 EXPORT_SYMBOL(xfrm_policy_walk_init);
 895
 896 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk)
 897 {
 898         if (list_empty(&walk->walk.all))
 899                 return;
 900
 901         write_lock_bh(&xfrm_policy_lock);
 902         list_del(&walk->walk.all);
 903         write_unlock_bh(&xfrm_policy_lock);
 904 }
 905 EXPORT_SYMBOL(xfrm_policy_walk_done);
 906
 907 /*
 908  * Find policy to apply to this flow.
 909  *
 910  * Returns 0 if policy found, else an -errno.
 911  */
 912 static int xfrm_policy_match(struct xfrm_policy *pol, struct flowi *fl,
 913                              u8 type, u16 family, int dir)
 914 {
 915         struct xfrm_selector *sel = &pol->selector;
 916         int match, ret = -ESRCH;
 917
 918         if (pol->family != family ||
 919             pol->type != type)
 920                 return ret;
 921
 922         match = xfrm_selector_match(sel, fl, family);
 923         if (match)
 924                 ret = security_xfrm_policy_lookup(pol->security, fl->secid,
 925                                                   dir);
 926
 927         return ret;
 928 }
 929
 930 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 931                                                      struct flowi *fl,
 932                                                      u16 family, u8 dir)
 933 {
 934         int err;
 935         struct xfrm_policy *pol, *ret;
 936         xfrm_address_t *daddr, *saddr;
 937         struct hlist_node *entry;
 938         struct hlist_head *chain;
 939         u32 priority = ~0U;
 940
 941         daddr = xfrm_flowi_daddr(fl, family);
 942         saddr = xfrm_flowi_saddr(fl, family);
 943         if (unlikely(!daddr || !saddr))
 944                 return NULL;
 945
 946         read_lock_bh(&xfrm_policy_lock);
 947         chain = policy_hash_direct(net, daddr, saddr, family, dir);
 948         ret = NULL;
 949         hlist_for_each_entry(pol, entry, chain, bydst) {
 950                 err = xfrm_policy_match(pol, fl, type, family, dir);
 951                 if (err) {
 952                         if (err == -ESRCH)
 953                                 continue;
 954                         else {
 955                                 ret = ERR_PTR(err);
 956                                 goto fail;
 957                         }
 958                 } else {
 959                         ret = pol;
 960                         priority = ret->priority;
 961                         break;
 962                 }
 963         }
 964         chain = &net->xfrm.policy_inexact[dir];
 965         hlist_for_each_entry(pol, entry, chain, bydst) {
 966                 err = xfrm_policy_match(pol, fl, type, family, dir);
 967                 if (err) {
 968                         if (err == -ESRCH)
 969                                 continue;
 970                         else {
 971                                 ret = ERR_PTR(err);
 972                                 goto fail;
 973                         }
 974                 } else if (pol->priority < priority) {
 975                         ret = pol;
 976                         break;
 977                 }
 978         }
 979         if (ret)
 980                 xfrm_pol_hold(ret);
 981 fail:
 982         read_unlock_bh(&xfrm_policy_lock);
 983
 984         return ret;
 985 }
 986
 987 static int xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family,
 988                               u8 dir, void **objp, atomic_t **obj_refp)
 989 {
 990         struct xfrm_policy *pol;
 991         int err = 0;
 992
 993 #ifdef CONFIG_XFRM_SUB_POLICY
 994         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
 995         if (IS_ERR(pol)) {
 996                 err = PTR_ERR(pol);
 997                 pol = NULL;
 998         }
 999         if (pol || err)
1000                 goto end;
1001 #endif
1002         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
1003         if (IS_ERR(pol)) {
1004                 err = PTR_ERR(pol);
1005                 pol = NULL;
1006         }
1007 #ifdef CONFIG_XFRM_SUB_POLICY
1008 end:
1009 #endif
1010         if ((*objp = (void *) pol) != NULL)
1011                 *obj_refp = &pol->refcnt;
1012         return err;
1013 }
1014
1015 static inline int policy_to_flow_dir(int dir)
1016 {
1017         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1018             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1019             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1020                 return dir;
1021         switch (dir) {
1022         default:
1023         case XFRM_POLICY_IN:
1024                 return FLOW_DIR_IN;
1025         case XFRM_POLICY_OUT:
1026                 return FLOW_DIR_OUT;
1027         case XFRM_POLICY_FWD:
1028                 return FLOW_DIR_FWD;
1029         }
1030 }
1031
1032 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
1033 {
1034         struct xfrm_policy *pol;
1035
1036         read_lock_bh(&xfrm_policy_lock);
1037         if ((pol = sk->sk_policy[dir]) != NULL) {
1038                 int match = xfrm_selector_match(&pol->selector, fl,
1039                                                 sk->sk_family);
1040                 int err = 0;
1041
1042                 if (match) {
1043                         err = security_xfrm_policy_lookup(pol->security,
1044                                                       fl->secid,
1045                                                       policy_to_flow_dir(dir));
1046                         if (!err)
1047                                 xfrm_pol_hold(pol);
1048                         else if (err == -ESRCH)
1049                                 pol = NULL;
1050                         else
1051                                 pol = ERR_PTR(err);
1052                 } else
1053                         pol = NULL;
1054         }
1055         read_unlock_bh(&xfrm_policy_lock);
1056         return pol;
1057 }
1058
1059 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1060 {
1061         struct net *net = xp_net(pol);
1062         struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1063                                                      pol->family, dir);
1064
1065         list_add(&pol->walk.all, &net->xfrm.policy_all);
1066         hlist_add_head(&pol->bydst, chain);
1067         hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1068         net->xfrm.policy_count[dir]++;
1069         xfrm_pol_hold(pol);
1070
1071         if (xfrm_bydst_should_resize(net, dir, NULL))
1072                 schedule_work(&net->xfrm.policy_hash_work);
1073 }
1074
1075 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1076                                                 int dir)
1077 {
1078         struct net *net = xp_net(pol);
1079
1080         if (hlist_unhashed(&pol->bydst))
1081                 return NULL;
1082
1083         hlist_del(&pol->bydst);
1084         hlist_del(&pol->byidx);
1085         list_del(&pol->walk.all);
1086         net->xfrm.policy_count[dir]--;
1087
1088         return pol;
1089 }
1090
1091 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1092 {
1093         write_lock_bh(&xfrm_policy_lock);
1094         pol = __xfrm_policy_unlink(pol, dir);
1095         write_unlock_bh(&xfrm_policy_lock);
1096         if (pol) {
1097                 if (dir < XFRM_POLICY_MAX)
1098                         atomic_inc(&flow_cache_genid);
1099                 xfrm_policy_kill(pol);
1100                 return 0;
1101         }
1102         return -ENOENT;
1103 }
1104 EXPORT_SYMBOL(xfrm_policy_delete);
1105
1106 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1107 {
1108         struct net *net = xp_net(pol);
1109         struct xfrm_policy *old_pol;
1110
1111 #ifdef CONFIG_XFRM_SUB_POLICY
1112         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1113                 return -EINVAL;
1114 #endif
1115
1116         write_lock_bh(&xfrm_policy_lock);
1117         old_pol = sk->sk_policy[dir];
1118         sk->sk_policy[dir] = pol;
1119         if (pol) {
1120                 pol->curlft.add_time = get_seconds();
1121                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir);
1122                 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1123         }
1124         if (old_pol)
1125                 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1126         write_unlock_bh(&xfrm_policy_lock);
1127
1128         if (old_pol) {
1129                 xfrm_policy_kill(old_pol);
1130         }
1131         return 0;
1132 }
1133
1134 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
1135 {
1136         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1137
1138         if (newp) {
1139                 newp->selector = old->selector;
1140                 if (security_xfrm_policy_clone(old->security,
1141                                                &newp->security)) {
1142                         kfree(newp);
1143                         return NULL;  /* ENOMEM */
1144                 }
1145                 newp->lft = old->lft;
1146                 newp->curlft = old->curlft;
1147                 newp->action = old->action;
1148                 newp->flags = old->flags;
1149                 newp->xfrm_nr = old->xfrm_nr;
1150                 newp->index = old->index;
1151                 newp->type = old->type;
1152                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1153                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1154                 write_lock_bh(&xfrm_policy_lock);
1155                 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1156                 write_unlock_bh(&xfrm_policy_lock);
1157                 xfrm_pol_put(newp);
1158         }
1159         return newp;
1160 }
1161
1162 int __xfrm_sk_clone_policy(struct sock *sk)
1163 {
1164         struct xfrm_policy *p0 = sk->sk_policy[0],
1165                            *p1 = sk->sk_policy[1];
1166
1167         sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1168         if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1169                 return -ENOMEM;
1170         if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1171                 return -ENOMEM;
1172         return 0;
1173 }
1174
1175 static int
1176 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1177                unsigned short family)
1178 {
1179         int err;
1180         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1181
1182         if (unlikely(afinfo == NULL))
1183                 return -EINVAL;
1184         err = afinfo->get_saddr(net, local, remote);
1185         xfrm_policy_put_afinfo(afinfo);
1186         return err;
1187 }
1188
1189 /* Resolve list of templates for the flow, given policy. */
1190
1191 static int
1192 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, struct flowi *fl,
1193                       struct xfrm_state **xfrm,
1194                       unsigned short family)
1195 {
1196         struct net *net = xp_net(policy);
1197         int nx;
1198         int i, error;
1199         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1200         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1201         xfrm_address_t tmp;
1202
1203         for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1204                 struct xfrm_state *x;
1205                 xfrm_address_t *remote = daddr;
1206                 xfrm_address_t *local  = saddr;
1207                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1208
1209                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1210                     tmpl->mode == XFRM_MODE_BEET) {
1211                         remote = &tmpl->id.daddr;
1212                         local = &tmpl->saddr;
1213                         family = tmpl->encap_family;
1214                         if (xfrm_addr_any(local, family)) {
1215                                 error = xfrm_get_saddr(net, &tmp, remote, family);
1216                                 if (error)
1217                                         goto fail;
1218                                 local = &tmp;
1219                         }
1220                 }
1221
1222                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1223
1224                 if (x && x->km.state == XFRM_STATE_VALID) {
1225                         xfrm[nx++] = x;
1226                         daddr = remote;
1227                         saddr = local;
1228                         continue;
1229                 }
1230                 if (x) {
1231                         error = (x->km.state == XFRM_STATE_ERROR ?
1232                                  -EINVAL : -EAGAIN);
1233                         xfrm_state_put(x);
1234                 }
1235                 else if (error == -ESRCH)
1236                         error = -EAGAIN;
1237
1238                 if (!tmpl->optional)
1239                         goto fail;
1240         }
1241         return nx;
1242
1243 fail:
1244         for (nx--; nx>=0; nx--)
1245                 xfrm_state_put(xfrm[nx]);
1246         return error;
1247 }
1248
1249 static int
1250 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
1251                   struct xfrm_state **xfrm,
1252                   unsigned short family)
1253 {
1254         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1255         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1256         int cnx = 0;
1257         int error;
1258         int ret;
1259         int i;
1260
1261         for (i = 0; i < npols; i++) {
1262                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1263                         error = -ENOBUFS;
1264                         goto fail;
1265                 }
1266
1267                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1268                 if (ret < 0) {
1269                         error = ret;
1270                         goto fail;
1271                 } else
1272                         cnx += ret;
1273         }
1274
1275         /* found states are sorted for outbound processing */
1276         if (npols > 1)
1277                 xfrm_state_sort(xfrm, tpp, cnx, family);
1278
1279         return cnx;
1280
1281  fail:
1282         for (cnx--; cnx>=0; cnx--)
1283                 xfrm_state_put(tpp[cnx]);
1284         return error;
1285
1286 }
1287
1288 /* Check that the bundle accepts the flow and its components are
1289  * still valid.
1290  */
1291
1292 static struct dst_entry *
1293 xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family)
1294 {
1295         struct dst_entry *x;
1296         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1297         if (unlikely(afinfo == NULL))
1298                 return ERR_PTR(-EINVAL);
1299         x = afinfo->find_bundle(fl, policy);
1300         xfrm_policy_put_afinfo(afinfo);
1301         return x;
1302 }
1303
1304 static inline int xfrm_get_tos(struct flowi *fl, int family)
1305 {
1306         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1307         int tos;
1308
1309         if (!afinfo)
1310                 return -EINVAL;
1311
1312         tos = afinfo->get_tos(fl);
1313
1314         xfrm_policy_put_afinfo(afinfo);
1315
1316         return tos;
1317 }
1318
1319 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1320 {
1321         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1322         struct dst_ops *dst_ops;
1323         struct xfrm_dst *xdst;
1324
1325         if (!afinfo)
1326                 return ERR_PTR(-EINVAL);
1327
1328         switch (family) {
1329         case AF_INET:
1330                 dst_ops = &net->xfrm.xfrm4_dst_ops;
1331                 break;
1332 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1333         case AF_INET6:
1334                 dst_ops = &net->xfrm.xfrm6_dst_ops;
1335                 break;
1336 #endif
1337         default:
1338                 BUG();
1339         }
1340         xdst = dst_alloc(dst_ops) ?: ERR_PTR(-ENOBUFS);
1341
1342         xfrm_policy_put_afinfo(afinfo);
1343
1344         return xdst;
1345 }
1346
1347 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1348                                  int nfheader_len)
1349 {
1350         struct xfrm_policy_afinfo *afinfo =
1351                 xfrm_policy_get_afinfo(dst->ops->family);
1352         int err;
1353
1354         if (!afinfo)
1355                 return -EINVAL;
1356
1357         err = afinfo->init_path(path, dst, nfheader_len);
1358
1359         xfrm_policy_put_afinfo(afinfo);
1360
1361         return err;
1362 }
1363
1364 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev)
1365 {
1366         struct xfrm_policy_afinfo *afinfo =
1367                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1368         int err;
1369
1370         if (!afinfo)
1371                 return -EINVAL;
1372
1373         err = afinfo->fill_dst(xdst, dev);
1374
1375         xfrm_policy_put_afinfo(afinfo);
1376
1377         return err;
1378 }
1379
1380 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1381  * all the metrics... Shortly, bundle a bundle.
1382  */
1383
1384 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1385                                             struct xfrm_state **xfrm, int nx,
1386                                             struct flowi *fl,
1387                                             struct dst_entry *dst)
1388 {
1389         struct net *net = xp_net(policy);
1390         unsigned long now = jiffies;
1391         struct net_device *dev;
1392         struct dst_entry *dst_prev = NULL;
1393         struct dst_entry *dst0 = NULL;
1394         int i = 0;
1395         int err;
1396         int header_len = 0;
1397         int nfheader_len = 0;
1398         int trailer_len = 0;
1399         int tos;
1400         int family = policy->selector.family;
1401         xfrm_address_t saddr, daddr;
1402
1403         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1404
1405         tos = xfrm_get_tos(fl, family);
1406         err = tos;
1407         if (tos < 0)
1408                 goto put_states;
1409
1410         dst_hold(dst);
1411
1412         for (; i < nx; i++) {
1413                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1414                 struct dst_entry *dst1 = &xdst->u.dst;
1415
1416                 err = PTR_ERR(xdst);
1417                 if (IS_ERR(xdst)) {
1418                         dst_release(dst);
1419                         goto put_states;
1420                 }
1421
1422                 if (!dst_prev)
1423                         dst0 = dst1;
1424                 else {
1425                         dst_prev->child = dst_clone(dst1);
1426                         dst1->flags |= DST_NOHASH;
1427                 }
1428
1429                 xdst->route = dst;
1430                 memcpy(&dst1->metrics, &dst->metrics, sizeof(dst->metrics));
1431
1432                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1433                         family = xfrm[i]->props.family;
1434                         dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1435                                               family);
1436                         err = PTR_ERR(dst);
1437                         if (IS_ERR(dst))
1438                                 goto put_states;
1439                 } else
1440                         dst_hold(dst);
1441
1442                 dst1->xfrm = xfrm[i];
1443                 xdst->genid = xfrm[i]->genid;
1444
1445                 dst1->obsolete = -1;
1446                 dst1->flags |= DST_HOST;
1447                 dst1->lastuse = now;
1448
1449                 dst1->input = dst_discard;
1450                 dst1->output = xfrm[i]->outer_mode->afinfo->output;
1451
1452                 dst1->next = dst_prev;
1453                 dst_prev = dst1;
1454
1455                 header_len += xfrm[i]->props.header_len;
1456                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1457                         nfheader_len += xfrm[i]->props.header_len;
1458                 trailer_len += xfrm[i]->props.trailer_len;
1459         }
1460
1461         dst_prev->child = dst;
1462         dst0->path = dst;
1463
1464         err = -ENODEV;
1465         dev = dst->dev;
1466         if (!dev)
1467                 goto free_dst;
1468
1469         /* Copy neighbour for reachability confirmation */
1470         dst0->neighbour = neigh_clone(dst->neighbour);
1471
1472         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1473         xfrm_init_pmtu(dst_prev);
1474
1475         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1476                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1477
1478                 err = xfrm_fill_dst(xdst, dev);
1479                 if (err)
1480                         goto free_dst;
1481
1482                 dst_prev->header_len = header_len;
1483                 dst_prev->trailer_len = trailer_len;
1484                 header_len -= xdst->u.dst.xfrm->props.header_len;
1485                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1486         }
1487
1488 out:
1489         return dst0;
1490
1491 put_states:
1492         for (; i < nx; i++)
1493                 xfrm_state_put(xfrm[i]);
1494 free_dst:
1495         if (dst0)
1496                 dst_free(dst0);
1497         dst0 = ERR_PTR(err);
1498         goto out;
1499 }
1500
1501 static int inline
1502 xfrm_dst_alloc_copy(void **target, void *src, int size)
1503 {
1504         if (!*target) {
1505                 *target = kmalloc(size, GFP_ATOMIC);
1506                 if (!*target)
1507                         return -ENOMEM;
1508         }
1509         memcpy(*target, src, size);
1510         return 0;
1511 }
1512
1513 static int inline
1514 xfrm_dst_update_parent(struct dst_entry *dst, struct xfrm_selector *sel)
1515 {
1516 #ifdef CONFIG_XFRM_SUB_POLICY
1517         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1518         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1519                                    sel, sizeof(*sel));
1520 #else
1521         return 0;
1522 #endif
1523 }
1524
1525 static int inline
1526 xfrm_dst_update_origin(struct dst_entry *dst, struct flowi *fl)
1527 {
1528 #ifdef CONFIG_XFRM_SUB_POLICY
1529         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1530         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1531 #else
1532         return 0;
1533 #endif
1534 }
1535
1536 static int stale_bundle(struct dst_entry *dst);
1537
1538 /* Main function: finds/creates a bundle for given flow.
1539  *
1540  * At the moment we eat a raw IP route. Mostly to speed up lookups
1541  * on interfaces with disabled IPsec.
1542  */
1543 int __xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
1544                   struct sock *sk, int flags)
1545 {
1546         struct xfrm_policy *policy;
1547         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1548         int npols;
1549         int pol_dead;
1550         int xfrm_nr;
1551         int pi;
1552         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1553         struct dst_entry *dst, *dst_orig = *dst_p;
1554         int nx = 0;
1555         int err;
1556         u32 genid;
1557         u16 family;
1558         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
1559
1560 restart:
1561         genid = atomic_read(&flow_cache_genid);
1562         policy = NULL;
1563         for (pi = 0; pi < ARRAY_SIZE(pols); pi++)
1564                 pols[pi] = NULL;
1565         npols = 0;
1566         pol_dead = 0;
1567         xfrm_nr = 0;
1568
1569         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
1570                 policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
1571                 err = PTR_ERR(policy);
1572                 if (IS_ERR(policy)) {
1573                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1574                         goto dropdst;
1575                 }
1576         }
1577
1578         if (!policy) {
1579                 /* To accelerate a bit...  */
1580                 if ((dst_orig->flags & DST_NOXFRM) ||
1581                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
1582                         goto nopol;
1583
1584                 policy = flow_cache_lookup(net, fl, dst_orig->ops->family,
1585                                            dir, xfrm_policy_lookup);
1586                 err = PTR_ERR(policy);
1587                 if (IS_ERR(policy)) {
1588                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1589                         goto dropdst;
1590                 }
1591         }
1592
1593         if (!policy)
1594                 goto nopol;
1595
1596         family = dst_orig->ops->family;
1597         pols[0] = policy;
1598         npols ++;
1599         xfrm_nr += pols[0]->xfrm_nr;
1600
1601         err = -ENOENT;
1602         if ((flags & XFRM_LOOKUP_ICMP) && !(policy->flags & XFRM_POLICY_ICMP))
1603                 goto error;
1604
1605         policy->curlft.use_time = get_seconds();
1606
1607         switch (policy->action) {
1608         default:
1609         case XFRM_POLICY_BLOCK:
1610                 /* Prohibit the flow */
1611                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
1612                 err = -EPERM;
1613                 goto error;
1614
1615         case XFRM_POLICY_ALLOW:
1616 #ifndef CONFIG_XFRM_SUB_POLICY
1617                 if (policy->xfrm_nr == 0) {
1618                         /* Flow passes not transformed. */
1619                         xfrm_pol_put(policy);
1620                         return 0;
1621                 }
1622 #endif
1623
1624                 /* Try to find matching bundle.
1625                  *
1626                  * LATER: help from flow cache. It is optional, this
1627                  * is required only for output policy.
1628                  */
1629                 dst = xfrm_find_bundle(fl, policy, family);
1630                 if (IS_ERR(dst)) {
1631                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1632                         err = PTR_ERR(dst);
1633                         goto error;
1634                 }
1635
1636                 if (dst)
1637                         break;
1638
1639 #ifdef CONFIG_XFRM_SUB_POLICY
1640                 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1641                         pols[1] = xfrm_policy_lookup_bytype(net,
1642                                                             XFRM_POLICY_TYPE_MAIN,
1643                                                             fl, family,
1644                                                             XFRM_POLICY_OUT);
1645                         if (pols[1]) {
1646                                 if (IS_ERR(pols[1])) {
1647                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1648                                         err = PTR_ERR(pols[1]);
1649                                         goto error;
1650                                 }
1651                                 if (pols[1]->action == XFRM_POLICY_BLOCK) {
1652                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
1653                                         err = -EPERM;
1654                                         goto error;
1655                                 }
1656                                 npols ++;
1657                                 xfrm_nr += pols[1]->xfrm_nr;
1658                         }
1659                 }
1660
1661                 /*
1662                  * Because neither flowi nor bundle information knows about
1663                  * transformation template size. On more than one policy usage
1664                  * we can realize whether all of them is bypass or not after
1665                  * they are searched. See above not-transformed bypass
1666                  * is surrounded by non-sub policy configuration, too.
1667                  */
1668                 if (xfrm_nr == 0) {
1669                         /* Flow passes not transformed. */
1670                         xfrm_pols_put(pols, npols);
1671                         return 0;
1672                 }
1673
1674 #endif
1675                 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1676
1677                 if (unlikely(nx<0)) {
1678                         err = nx;
1679                         if (err == -EAGAIN && net->xfrm.sysctl_larval_drop) {
1680                                 /* EREMOTE tells the caller to generate
1681                                  * a one-shot blackhole route.
1682                                  */
1683                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1684                                 xfrm_pol_put(policy);
1685                                 return -EREMOTE;
1686                         }
1687                         if (err == -EAGAIN && (flags & XFRM_LOOKUP_WAIT)) {
1688                                 DECLARE_WAITQUEUE(wait, current);
1689
1690                                 add_wait_queue(&net->xfrm.km_waitq, &wait);
1691                                 set_current_state(TASK_INTERRUPTIBLE);
1692                                 schedule();
1693                                 set_current_state(TASK_RUNNING);
1694                                 remove_wait_queue(&net->xfrm.km_waitq, &wait);
1695
1696                                 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1697
1698                                 if (nx == -EAGAIN && signal_pending(current)) {
1699                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1700                                         err = -ERESTART;
1701                                         goto error;
1702                                 }
1703                                 if (nx == -EAGAIN ||
1704                                     genid != atomic_read(&flow_cache_genid)) {
1705                                         xfrm_pols_put(pols, npols);
1706                                         goto restart;
1707                                 }
1708                                 err = nx;
1709                         }
1710                         if (err < 0) {
1711                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1712                                 goto error;
1713                         }
1714                 }
1715                 if (nx == 0) {
1716                         /* Flow passes not transformed. */
1717                         xfrm_pols_put(pols, npols);
1718                         return 0;
1719                 }
1720
1721                 dst = xfrm_bundle_create(policy, xfrm, nx, fl, dst_orig);
1722                 err = PTR_ERR(dst);
1723                 if (IS_ERR(dst)) {
1724                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1725                         goto error;
1726                 }
1727
1728                 for (pi = 0; pi < npols; pi++) {
1729                         read_lock_bh(&pols[pi]->lock);
1730                         pol_dead |= pols[pi]->walk.dead;
1731                         read_unlock_bh(&pols[pi]->lock);
1732                 }
1733
1734                 write_lock_bh(&policy->lock);
1735                 if (unlikely(pol_dead || stale_bundle(dst))) {
1736                         /* Wow! While we worked on resolving, this
1737                          * policy has gone. Retry. It is not paranoia,
1738                          * we just cannot enlist new bundle to dead object.
1739                          * We can't enlist stable bundles either.
1740                          */
1741                         write_unlock_bh(&policy->lock);
1742                         dst_free(dst);
1743
1744                         if (pol_dead)
1745                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLDEAD);
1746                         else
1747                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1748                         err = -EHOSTUNREACH;
1749                         goto error;
1750                 }
1751
1752                 if (npols > 1)
1753                         err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1754                 else
1755                         err = xfrm_dst_update_origin(dst, fl);
1756                 if (unlikely(err)) {
1757                         write_unlock_bh(&policy->lock);
1758                         dst_free(dst);
1759                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1760                         goto error;
1761                 }
1762
1763                 dst->next = policy->bundles;
1764                 policy->bundles = dst;
1765                 dst_hold(dst);
1766                 write_unlock_bh(&policy->lock);
1767         }
1768         *dst_p = dst;
1769         dst_release(dst_orig);
1770         xfrm_pols_put(pols, npols);
1771         return 0;
1772
1773 error:
1774         xfrm_pols_put(pols, npols);
1775 dropdst:
1776         dst_release(dst_orig);
1777         *dst_p = NULL;
1778         return err;
1779
1780 nopol:
1781         err = -ENOENT;
1782         if (flags & XFRM_LOOKUP_ICMP)
1783                 goto dropdst;
1784         return 0;
1785 }
1786 EXPORT_SYMBOL(__xfrm_lookup);
1787
1788 int xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
1789                 struct sock *sk, int flags)
1790 {
1791         int err = __xfrm_lookup(net, dst_p, fl, sk, flags);
1792
1793         if (err == -EREMOTE) {
1794                 dst_release(*dst_p);
1795                 *dst_p = NULL;
1796                 err = -EAGAIN;
1797         }
1798
1799         return err;
1800 }
1801 EXPORT_SYMBOL(xfrm_lookup);
1802
1803 static inline int
1804 xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
1805 {
1806         struct xfrm_state *x;
1807
1808         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1809                 return 0;
1810         x = skb->sp->xvec[idx];
1811         if (!x->type->reject)
1812                 return 0;
1813         return x->type->reject(x, skb, fl);
1814 }
1815
1816 /* When skb is transformed back to its "native" form, we have to
1817  * check policy restrictions. At the moment we make this in maximally
1818  * stupid way. Shame on me. :-) Of course, connected sockets must
1819  * have policy cached at them.
1820  */
1821
1822 static inline int
1823 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
1824               unsigned short family)
1825 {
1826         if (xfrm_state_kern(x))
1827                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
1828         return  x->id.proto == tmpl->id.proto &&
1829                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1830                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1831                 x->props.mode == tmpl->mode &&
1832                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
1833                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1834                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
1835                   xfrm_state_addr_cmp(tmpl, x, family));
1836 }
1837
1838 /*
1839  * 0 or more than 0 is returned when validation is succeeded (either bypass
1840  * because of optional transport mode, or next index of the mathced secpath
1841  * state with the template.
1842  * -1 is returned when no matching template is found.
1843  * Otherwise "-2 - errored_index" is returned.
1844  */
1845 static inline int
1846 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1847                unsigned short family)
1848 {
1849         int idx = start;
1850
1851         if (tmpl->optional) {
1852                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
1853                         return start;
1854         } else
1855                 start = -1;
1856         for (; idx < sp->len; idx++) {
1857                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1858                         return ++idx;
1859                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
1860                         if (start == -1)
1861                                 start = -2-idx;
1862                         break;
1863                 }
1864         }
1865         return start;
1866 }
1867
1868 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1869                           unsigned int family, int reverse)
1870 {
1871         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1872         int err;
1873
1874         if (unlikely(afinfo == NULL))
1875                 return -EAFNOSUPPORT;
1876
1877         afinfo->decode_session(skb, fl, reverse);
1878         err = security_xfrm_decode_session(skb, &fl->secid);
1879         xfrm_policy_put_afinfo(afinfo);
1880         return err;
1881 }
1882 EXPORT_SYMBOL(__xfrm_decode_session);
1883
1884 static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
1885 {
1886         for (; k < sp->len; k++) {
1887                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
1888                         *idxp = k;
1889                         return 1;
1890                 }
1891         }
1892
1893         return 0;
1894 }
1895
1896 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
1897                         unsigned short family)
1898 {
1899         struct net *net = dev_net(skb->dev);
1900         struct xfrm_policy *pol;
1901         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1902         int npols = 0;
1903         int xfrm_nr;
1904         int pi;
1905         int reverse;
1906         struct flowi fl;
1907         u8 fl_dir;
1908         int xerr_idx = -1;
1909
1910         reverse = dir & ~XFRM_POLICY_MASK;
1911         dir &= XFRM_POLICY_MASK;
1912         fl_dir = policy_to_flow_dir(dir);
1913
1914         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
1915                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
1916                 return 0;
1917         }
1918
1919         nf_nat_decode_session(skb, &fl, family);
1920
1921         /* First, check used SA against their selectors. */
1922         if (skb->sp) {
1923                 int i;
1924
1925                 for (i=skb->sp->len-1; i>=0; i--) {
1926                         struct xfrm_state *x = skb->sp->xvec[i];
1927                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
1928                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
1929                                 return 0;
1930                         }
1931                 }
1932         }
1933
1934         pol = NULL;
1935         if (sk && sk->sk_policy[dir]) {
1936                 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
1937                 if (IS_ERR(pol)) {
1938                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
1939                         return 0;
1940                 }
1941         }
1942
1943         if (!pol)
1944                 pol = flow_cache_lookup(net, &fl, family, fl_dir,
1945                                         xfrm_policy_lookup);
1946
1947         if (IS_ERR(pol)) {
1948                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
1949                 return 0;
1950         }
1951
1952         if (!pol) {
1953                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
1954                         xfrm_secpath_reject(xerr_idx, skb, &fl);
1955                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
1956                         return 0;
1957                 }
1958                 return 1;
1959         }
1960
1961         pol->curlft.use_time = get_seconds();
1962
1963         pols[0] = pol;
1964         npols ++;
1965 #ifdef CONFIG_XFRM_SUB_POLICY
1966         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1967                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
1968                                                     &fl, family,
1969                                                     XFRM_POLICY_IN);
1970                 if (pols[1]) {
1971                         if (IS_ERR(pols[1])) {
1972                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
1973                                 return 0;
1974                         }
1975                         pols[1]->curlft.use_time = get_seconds();
1976                         npols ++;
1977                 }
1978         }
1979 #endif
1980
1981         if (pol->action == XFRM_POLICY_ALLOW) {
1982                 struct sec_path *sp;
1983                 static struct sec_path dummy;
1984                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
1985                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
1986                 struct xfrm_tmpl **tpp = tp;
1987                 int ti = 0;
1988                 int i, k;
1989
1990                 if ((sp = skb->sp) == NULL)
1991                         sp = &dummy;
1992
1993                 for (pi = 0; pi < npols; pi++) {
1994                         if (pols[pi] != pol &&
1995                             pols[pi]->action != XFRM_POLICY_ALLOW) {
1996                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
1997                                 goto reject;
1998                         }
1999                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2000                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2001                                 goto reject_error;
2002                         }
2003                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
2004                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
2005                 }
2006                 xfrm_nr = ti;
2007                 if (npols > 1) {
2008                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
2009                         tpp = stp;
2010                 }
2011
2012                 /* For each tunnel xfrm, find the first matching tmpl.
2013                  * For each tmpl before that, find corresponding xfrm.
2014                  * Order is _important_. Later we will implement
2015                  * some barriers, but at the moment barriers
2016                  * are implied between each two transformations.
2017                  */
2018                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2019                         k = xfrm_policy_ok(tpp[i], sp, k, family);
2020                         if (k < 0) {
2021                                 if (k < -1)
2022                                         /* "-2 - errored_index" returned */
2023                                         xerr_idx = -(2+k);
2024                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2025                                 goto reject;
2026                         }
2027                 }
2028
2029                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2030                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2031                         goto reject;
2032                 }
2033
2034                 xfrm_pols_put(pols, npols);
2035                 return 1;
2036         }
2037         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2038
2039 reject:
2040         xfrm_secpath_reject(xerr_idx, skb, &fl);
2041 reject_error:
2042         xfrm_pols_put(pols, npols);
2043         return 0;
2044 }
2045 EXPORT_SYMBOL(__xfrm_policy_check);
2046
2047 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2048 {
2049         struct net *net = dev_net(skb->dev);
2050         struct flowi fl;
2051         struct dst_entry *dst;
2052         int res;
2053
2054         if (xfrm_decode_session(skb, &fl, family) < 0) {
2055                 /* XXX: we should have something like FWDHDRERROR here. */
2056                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2057                 return 0;
2058         }
2059
2060         dst = skb_dst(skb);
2061
2062         res = xfrm_lookup(net, &dst, &fl, NULL, 0) == 0;
2063         skb_dst_set(skb, dst);
2064         return res;
2065 }
2066 EXPORT_SYMBOL(__xfrm_route_forward);
2067
2068 /* Optimize later using cookies and generation ids. */
2069
2070 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2071 {
2072         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2073          * to "-1" to force all XFRM destinations to get validated by
2074          * dst_ops->check on every use.  We do this because when a
2075          * normal route referenced by an XFRM dst is obsoleted we do
2076          * not go looking around for all parent referencing XFRM dsts
2077          * so that we can invalidate them.  It is just too much work.
2078          * Instead we make the checks here on every use.  For example:
2079          *
2080          *      XFRM dst A --> IPv4 dst X
2081          *
2082          * X is the "xdst->route" of A (X is also the "dst->path" of A
2083          * in this example).  If X is marked obsolete, "A" will not
2084          * notice.  That's what we are validating here via the
2085          * stale_bundle() check.
2086          *
2087          * When a policy's bundle is pruned, we dst_free() the XFRM
2088          * dst which causes it's ->obsolete field to be set to a
2089          * positive non-zero integer.  If an XFRM dst has been pruned
2090          * like this, we want to force a new route lookup.
2091          */
2092         if (dst->obsolete < 0 && !stale_bundle(dst))
2093                 return dst;
2094
2095         return NULL;
2096 }
2097
2098 static int stale_bundle(struct dst_entry *dst)
2099 {
2100         return !xfrm_bundle_ok(NULL, (struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
2101 }
2102
2103 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2104 {
2105         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2106                 dst->dev = dev_net(dev)->loopback_dev;
2107                 dev_hold(dst->dev);
2108                 dev_put(dev);
2109         }
2110 }
2111 EXPORT_SYMBOL(xfrm_dst_ifdown);
2112
2113 static void xfrm_link_failure(struct sk_buff *skb)
2114 {
2115         /* Impossible. Such dst must be popped before reaches point of failure. */
2116         return;
2117 }
2118
2119 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2120 {
2121         if (dst) {
2122                 if (dst->obsolete) {
2123                         dst_release(dst);
2124                         dst = NULL;
2125                 }
2126         }
2127         return dst;
2128 }
2129
2130 static void prune_one_bundle(struct xfrm_policy *pol, int (*func)(struct dst_entry *), struct dst_entry **gc_list_p)
2131 {
2132         struct dst_entry *dst, **dstp;
2133
2134         write_lock(&pol->lock);
2135         dstp = &pol->bundles;
2136         while ((dst=*dstp) != NULL) {
2137                 if (func(dst)) {
2138                         *dstp = dst->next;
2139                         dst->next = *gc_list_p;
2140                         *gc_list_p = dst;
2141                 } else {
2142                         dstp = &dst->next;
2143                 }
2144         }
2145         write_unlock(&pol->lock);
2146 }
2147
2148 static void xfrm_prune_bundles(struct net *net, int (*func)(struct dst_entry *))
2149 {
2150         struct dst_entry *gc_list = NULL;
2151         int dir;
2152
2153         read_lock_bh(&xfrm_policy_lock);
2154         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2155                 struct xfrm_policy *pol;
2156                 struct hlist_node *entry;
2157                 struct hlist_head *table;
2158                 int i;
2159
2160                 hlist_for_each_entry(pol, entry,
2161                                      &net->xfrm.policy_inexact[dir], bydst)
2162                         prune_one_bundle(pol, func, &gc_list);
2163
2164                 table = net->xfrm.policy_bydst[dir].table;
2165                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
2166                         hlist_for_each_entry(pol, entry, table + i, bydst)
2167                                 prune_one_bundle(pol, func, &gc_list);
2168                 }
2169         }
2170         read_unlock_bh(&xfrm_policy_lock);
2171
2172         while (gc_list) {
2173                 struct dst_entry *dst = gc_list;
2174                 gc_list = dst->next;
2175                 dst_free(dst);
2176         }
2177 }
2178
2179 static int unused_bundle(struct dst_entry *dst)
2180 {
2181         return !atomic_read(&dst->__refcnt);
2182 }
2183
2184 static void __xfrm_garbage_collect(struct net *net)
2185 {
2186         xfrm_prune_bundles(net, unused_bundle);
2187 }
2188
2189 static int xfrm_flush_bundles(struct net *net)
2190 {
2191         xfrm_prune_bundles(net, stale_bundle);
2192         return 0;
2193 }
2194
2195 static void xfrm_init_pmtu(struct dst_entry *dst)
2196 {
2197         do {
2198                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2199                 u32 pmtu, route_mtu_cached;
2200
2201                 pmtu = dst_mtu(dst->child);
2202                 xdst->child_mtu_cached = pmtu;
2203
2204                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2205
2206                 route_mtu_cached = dst_mtu(xdst->route);
2207                 xdst->route_mtu_cached = route_mtu_cached;
2208
2209                 if (pmtu > route_mtu_cached)
2210                         pmtu = route_mtu_cached;
2211
2212                 dst->metrics[RTAX_MTU-1] = pmtu;
2213         } while ((dst = dst->next));
2214 }
2215
2216 /* Check that the bundle accepts the flow and its components are
2217  * still valid.
2218  */
2219
2220 int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
2221                 struct flowi *fl, int family, int strict)
2222 {
2223         struct dst_entry *dst = &first->u.dst;
2224         struct xfrm_dst *last;
2225         u32 mtu;
2226
2227         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2228             (dst->dev && !netif_running(dst->dev)))
2229                 return 0;
2230 #ifdef CONFIG_XFRM_SUB_POLICY
2231         if (fl) {
2232                 if (first->origin && !flow_cache_uli_match(first->origin, fl))
2233                         return 0;
2234                 if (first->partner &&
2235                     !xfrm_selector_match(first->partner, fl, family))
2236                         return 0;
2237         }
2238 #endif
2239
2240         last = NULL;
2241
2242         do {
2243                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2244
2245                 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
2246                         return 0;
2247                 if (fl && pol &&
2248                     !security_xfrm_state_pol_flow_match(dst->xfrm, pol, fl))
2249                         return 0;
2250                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2251                         return 0;
2252                 if (xdst->genid != dst->xfrm->genid)
2253                         return 0;
2254
2255                 if (strict && fl &&
2256                     !(dst->xfrm->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
2257                     !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
2258                         return 0;
2259
2260                 mtu = dst_mtu(dst->child);
2261                 if (xdst->child_mtu_cached != mtu) {
2262                         last = xdst;
2263                         xdst->child_mtu_cached = mtu;
2264                 }
2265
2266                 if (!dst_check(xdst->route, xdst->route_cookie))
2267                         return 0;
2268                 mtu = dst_mtu(xdst->route);
2269                 if (xdst->route_mtu_cached != mtu) {
2270                         last = xdst;
2271                         xdst->route_mtu_cached = mtu;
2272                 }
2273
2274                 dst = dst->child;
2275         } while (dst->xfrm);
2276
2277         if (likely(!last))
2278                 return 1;
2279
2280         mtu = last->child_mtu_cached;
2281         for (;;) {
2282                 dst = &last->u.dst;
2283
2284                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2285                 if (mtu > last->route_mtu_cached)
2286                         mtu = last->route_mtu_cached;
2287                 dst->metrics[RTAX_MTU-1] = mtu;
2288
2289                 if (last == first)
2290                         break;
2291
2292                 last = (struct xfrm_dst *)last->u.dst.next;
2293                 last->child_mtu_cached = mtu;
2294         }
2295
2296         return 1;
2297 }
2298
2299 EXPORT_SYMBOL(xfrm_bundle_ok);
2300
2301 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2302 {
2303         struct net *net;
2304         int err = 0;
2305         if (unlikely(afinfo == NULL))
2306                 return -EINVAL;
2307         if (unlikely(afinfo->family >= NPROTO))
2308                 return -EAFNOSUPPORT;
2309         write_lock_bh(&xfrm_policy_afinfo_lock);
2310         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2311                 err = -ENOBUFS;
2312         else {
2313                 struct dst_ops *dst_ops = afinfo->dst_ops;
2314                 if (likely(dst_ops->kmem_cachep == NULL))
2315                         dst_ops->kmem_cachep = xfrm_dst_cache;
2316                 if (likely(dst_ops->check == NULL))
2317                         dst_ops->check = xfrm_dst_check;
2318                 if (likely(dst_ops->negative_advice == NULL))
2319                         dst_ops->negative_advice = xfrm_negative_advice;
2320                 if (likely(dst_ops->link_failure == NULL))
2321                         dst_ops->link_failure = xfrm_link_failure;
2322                 if (likely(afinfo->garbage_collect == NULL))
2323                         afinfo->garbage_collect = __xfrm_garbage_collect;
2324                 xfrm_policy_afinfo[afinfo->family] = afinfo;
2325         }
2326         write_unlock_bh(&xfrm_policy_afinfo_lock);
2327
2328         rtnl_lock();
2329         for_each_net(net) {
2330                 struct dst_ops *xfrm_dst_ops;
2331
2332                 switch (afinfo->family) {
2333                 case AF_INET:
2334                         xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2335                         break;
2336 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2337                 case AF_INET6:
2338                         xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2339                         break;
2340 #endif
2341                 default:
2342                         BUG();
2343                 }
2344                 *xfrm_dst_ops = *afinfo->dst_ops;
2345         }
2346         rtnl_unlock();
2347
2348         return err;
2349 }
2350 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2351
2352 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2353 {
2354         int err = 0;
2355         if (unlikely(afinfo == NULL))
2356                 return -EINVAL;
2357         if (unlikely(afinfo->family >= NPROTO))
2358                 return -EAFNOSUPPORT;
2359         write_lock_bh(&xfrm_policy_afinfo_lock);
2360         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2361                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2362                         err = -EINVAL;
2363                 else {
2364                         struct dst_ops *dst_ops = afinfo->dst_ops;
2365                         xfrm_policy_afinfo[afinfo->family] = NULL;
2366                         dst_ops->kmem_cachep = NULL;
2367                         dst_ops->check = NULL;
2368                         dst_ops->negative_advice = NULL;
2369                         dst_ops->link_failure = NULL;
2370                         afinfo->garbage_collect = NULL;
2371                 }
2372         }
2373         write_unlock_bh(&xfrm_policy_afinfo_lock);
2374         return err;
2375 }
2376 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2377
2378 static void __net_init xfrm_dst_ops_init(struct net *net)
2379 {
2380         struct xfrm_policy_afinfo *afinfo;
2381
2382         read_lock_bh(&xfrm_policy_afinfo_lock);
2383         afinfo = xfrm_policy_afinfo[AF_INET];
2384         if (afinfo)
2385                 net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2386 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2387         afinfo = xfrm_policy_afinfo[AF_INET6];
2388         if (afinfo)
2389                 net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2390 #endif
2391         read_unlock_bh(&xfrm_policy_afinfo_lock);
2392 }
2393
2394 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
2395 {
2396         struct xfrm_policy_afinfo *afinfo;
2397         if (unlikely(family >= NPROTO))
2398                 return NULL;
2399         read_lock(&xfrm_policy_afinfo_lock);
2400         afinfo = xfrm_policy_afinfo[family];
2401         if (unlikely(!afinfo))
2402                 read_unlock(&xfrm_policy_afinfo_lock);
2403         return afinfo;
2404 }
2405
2406 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
2407 {
2408         read_unlock(&xfrm_policy_afinfo_lock);
2409 }
2410
2411 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2412 {
2413         struct net_device *dev = ptr;
2414
2415         switch (event) {
2416         case NETDEV_DOWN:
2417                 xfrm_flush_bundles(dev_net(dev));
2418         }
2419         return NOTIFY_DONE;
2420 }
2421
2422 static struct notifier_block xfrm_dev_notifier = {
2423         .notifier_call  = xfrm_dev_event,
2424 };
2425
2426 #ifdef CONFIG_XFRM_STATISTICS
2427 static int __net_init xfrm_statistics_init(struct net *net)
2428 {
2429         int rv;
2430
2431         if (snmp_mib_init((void __percpu **)net->mib.xfrm_statistics,
2432                           sizeof(struct linux_xfrm_mib)) < 0)
2433                 return -ENOMEM;
2434         rv = xfrm_proc_init(net);
2435         if (rv < 0)
2436                 snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2437         return rv;
2438 }
2439
2440 static void xfrm_statistics_fini(struct net *net)
2441 {
2442         xfrm_proc_fini(net);
2443         snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2444 }
2445 #else
2446 static int __net_init xfrm_statistics_init(struct net *net)
2447 {
2448         return 0;
2449 }
2450
2451 static void xfrm_statistics_fini(struct net *net)
2452 {
2453 }
2454 #endif
2455
2456 static int __net_init xfrm_policy_init(struct net *net)
2457 {
2458         unsigned int hmask, sz;
2459         int dir;
2460
2461         if (net_eq(net, &init_net))
2462                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2463                                            sizeof(struct xfrm_dst),
2464                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2465                                            NULL);
2466
2467         hmask = 8 - 1;
2468         sz = (hmask+1) * sizeof(struct hlist_head);
2469
2470         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2471         if (!net->xfrm.policy_byidx)
2472                 goto out_byidx;
2473         net->xfrm.policy_idx_hmask = hmask;
2474
2475         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2476                 struct xfrm_policy_hash *htab;
2477
2478                 net->xfrm.policy_count[dir] = 0;
2479                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2480
2481                 htab = &net->xfrm.policy_bydst[dir];
2482                 htab->table = xfrm_hash_alloc(sz);
2483                 if (!htab->table)
2484                         goto out_bydst;
2485                 htab->hmask = hmask;
2486         }
2487
2488         INIT_LIST_HEAD(&net->xfrm.policy_all);
2489         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2490         if (net_eq(net, &init_net))
2491                 register_netdevice_notifier(&xfrm_dev_notifier);
2492         return 0;
2493
2494 out_bydst:
2495         for (dir--; dir >= 0; dir--) {
2496                 struct xfrm_policy_hash *htab;
2497
2498                 htab = &net->xfrm.policy_bydst[dir];
2499                 xfrm_hash_free(htab->table, sz);
2500         }
2501         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2502 out_byidx:
2503         return -ENOMEM;
2504 }
2505
2506 static void xfrm_policy_fini(struct net *net)
2507 {
2508         struct xfrm_audit audit_info;
2509         unsigned int sz;
2510         int dir;
2511
2512         flush_work(&net->xfrm.policy_hash_work);
2513 #ifdef CONFIG_XFRM_SUB_POLICY
2514         audit_info.loginuid = -1;
2515         audit_info.sessionid = -1;
2516         audit_info.secid = 0;
2517         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info);
2518 #endif
2519         audit_info.loginuid = -1;
2520         audit_info.sessionid = -1;
2521         audit_info.secid = 0;
2522         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info);
2523         flush_work(&xfrm_policy_gc_work);
2524
2525         WARN_ON(!list_empty(&net->xfrm.policy_all));
2526
2527         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2528                 struct xfrm_policy_hash *htab;
2529
2530                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2531
2532                 htab = &net->xfrm.policy_bydst[dir];
2533                 sz = (htab->hmask + 1);
2534                 WARN_ON(!hlist_empty(htab->table));
2535                 xfrm_hash_free(htab->table, sz);
2536         }
2537
2538         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2539         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2540         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2541 }
2542
2543 static int __net_init xfrm_net_init(struct net *net)
2544 {
2545         int rv;
2546
2547         rv = xfrm_statistics_init(net);
2548         if (rv < 0)
2549                 goto out_statistics;
2550         rv = xfrm_state_init(net);
2551         if (rv < 0)
2552                 goto out_state;
2553         rv = xfrm_policy_init(net);
2554         if (rv < 0)
2555                 goto out_policy;
2556         xfrm_dst_ops_init(net);
2557         rv = xfrm_sysctl_init(net);
2558         if (rv < 0)
2559                 goto out_sysctl;
2560         return 0;
2561
2562 out_sysctl:
2563         xfrm_policy_fini(net);
2564 out_policy:
2565         xfrm_state_fini(net);
2566 out_state:
2567         xfrm_statistics_fini(net);
2568 out_statistics:
2569         return rv;
2570 }
2571
2572 static void __net_exit xfrm_net_exit(struct net *net)
2573 {
2574         xfrm_sysctl_fini(net);
2575         xfrm_policy_fini(net);
2576         xfrm_state_fini(net);
2577         xfrm_statistics_fini(net);
2578 }
2579
2580 static struct pernet_operations __net_initdata xfrm_net_ops = {
2581         .init = xfrm_net_init,
2582         .exit = xfrm_net_exit,
2583 };
2584
2585 void __init xfrm_init(void)
2586 {
2587         register_pernet_subsys(&xfrm_net_ops);
2588         xfrm_input_init();
2589 }
2590
2591 #ifdef CONFIG_AUDITSYSCALL
2592 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2593                                          struct audit_buffer *audit_buf)
2594 {
2595         struct xfrm_sec_ctx *ctx = xp->security;
2596         struct xfrm_selector *sel = &xp->selector;
2597
2598         if (ctx)
2599                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2600                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2601
2602         switch(sel->family) {
2603         case AF_INET:
2604                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2605                 if (sel->prefixlen_s != 32)
2606                         audit_log_format(audit_buf, " src_prefixlen=%d",
2607                                          sel->prefixlen_s);
2608                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2609                 if (sel->prefixlen_d != 32)
2610                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2611                                          sel->prefixlen_d);
2612                 break;
2613         case AF_INET6:
2614                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
2615                 if (sel->prefixlen_s != 128)
2616                         audit_log_format(audit_buf, " src_prefixlen=%d",
2617                                          sel->prefixlen_s);
2618                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
2619                 if (sel->prefixlen_d != 128)
2620                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2621                                          sel->prefixlen_d);
2622                 break;
2623         }
2624 }
2625
2626 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2627                            uid_t auid, u32 sessionid, u32 secid)
2628 {
2629         struct audit_buffer *audit_buf;
2630
2631         audit_buf = xfrm_audit_start("SPD-add");
2632         if (audit_buf == NULL)
2633                 return;
2634         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2635         audit_log_format(audit_buf, " res=%u", result);
2636         xfrm_audit_common_policyinfo(xp, audit_buf);
2637         audit_log_end(audit_buf);
2638 }
2639 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
2640
2641 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
2642                               uid_t auid, u32 sessionid, u32 secid)
2643 {
2644         struct audit_buffer *audit_buf;
2645
2646         audit_buf = xfrm_audit_start("SPD-delete");
2647         if (audit_buf == NULL)
2648                 return;
2649         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2650         audit_log_format(audit_buf, " res=%u", result);
2651         xfrm_audit_common_policyinfo(xp, audit_buf);
2652         audit_log_end(audit_buf);
2653 }
2654 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
2655 #endif
2656
2657 #ifdef CONFIG_XFRM_MIGRATE
2658 static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
2659                                        struct xfrm_selector *sel_tgt)
2660 {
2661         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
2662                 if (sel_tgt->family == sel_cmp->family &&
2663                     xfrm_addr_cmp(&sel_tgt->daddr, &sel_cmp->daddr,
2664                                   sel_cmp->family) == 0 &&
2665                     xfrm_addr_cmp(&sel_tgt->saddr, &sel_cmp->saddr,
2666                                   sel_cmp->family) == 0 &&
2667                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
2668                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
2669                         return 1;
2670                 }
2671         } else {
2672                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
2673                         return 1;
2674                 }
2675         }
2676         return 0;
2677 }
2678
2679 static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
2680                                                      u8 dir, u8 type)
2681 {
2682         struct xfrm_policy *pol, *ret = NULL;
2683         struct hlist_node *entry;
2684         struct hlist_head *chain;
2685         u32 priority = ~0U;
2686
2687         read_lock_bh(&xfrm_policy_lock);
2688         chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir);
2689         hlist_for_each_entry(pol, entry, chain, bydst) {
2690                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2691                     pol->type == type) {
2692                         ret = pol;
2693                         priority = ret->priority;
2694                         break;
2695                 }
2696         }
2697         chain = &init_net.xfrm.policy_inexact[dir];
2698         hlist_for_each_entry(pol, entry, chain, bydst) {
2699                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2700                     pol->type == type &&
2701                     pol->priority < priority) {
2702                         ret = pol;
2703                         break;
2704                 }
2705         }
2706
2707         if (ret)
2708                 xfrm_pol_hold(ret);
2709
2710         read_unlock_bh(&xfrm_policy_lock);
2711
2712         return ret;
2713 }
2714
2715 static int migrate_tmpl_match(struct xfrm_migrate *m, struct xfrm_tmpl *t)
2716 {
2717         int match = 0;
2718
2719         if (t->mode == m->mode && t->id.proto == m->proto &&
2720             (m->reqid == 0 || t->reqid == m->reqid)) {
2721                 switch (t->mode) {
2722                 case XFRM_MODE_TUNNEL:
2723                 case XFRM_MODE_BEET:
2724                         if (xfrm_addr_cmp(&t->id.daddr, &m->old_daddr,
2725                                           m->old_family) == 0 &&
2726                             xfrm_addr_cmp(&t->saddr, &m->old_saddr,
2727                                           m->old_family) == 0) {
2728                                 match = 1;
2729                         }
2730                         break;
2731                 case XFRM_MODE_TRANSPORT:
2732                         /* in case of transport mode, template does not store
2733                            any IP addresses, hence we just compare mode and
2734                            protocol */
2735                         match = 1;
2736                         break;
2737                 default:
2738                         break;
2739                 }
2740         }
2741         return match;
2742 }
2743
2744 /* update endpoint address(es) of template(s) */
2745 static int xfrm_policy_migrate(struct xfrm_policy *pol,
2746                                struct xfrm_migrate *m, int num_migrate)
2747 {
2748         struct xfrm_migrate *mp;
2749         struct dst_entry *dst;
2750         int i, j, n = 0;
2751
2752         write_lock_bh(&pol->lock);
2753         if (unlikely(pol->walk.dead)) {
2754                 /* target policy has been deleted */
2755                 write_unlock_bh(&pol->lock);
2756                 return -ENOENT;
2757         }
2758
2759         for (i = 0; i < pol->xfrm_nr; i++) {
2760                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
2761                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
2762                                 continue;
2763                         n++;
2764                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
2765                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
2766                                 continue;
2767                         /* update endpoints */
2768                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
2769                                sizeof(pol->xfrm_vec[i].id.daddr));
2770                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
2771                                sizeof(pol->xfrm_vec[i].saddr));
2772                         pol->xfrm_vec[i].encap_family = mp->new_family;
2773                         /* flush bundles */
2774                         while ((dst = pol->bundles) != NULL) {
2775                                 pol->bundles = dst->next;
2776                                 dst_free(dst);
2777                         }
2778                 }
2779         }
2780
2781         write_unlock_bh(&pol->lock);
2782
2783         if (!n)
2784                 return -ENODATA;
2785
2786         return 0;
2787 }
2788
2789 static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
2790 {
2791         int i, j;
2792
2793         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
2794                 return -EINVAL;
2795
2796         for (i = 0; i < num_migrate; i++) {
2797                 if ((xfrm_addr_cmp(&m[i].old_daddr, &m[i].new_daddr,
2798                                    m[i].old_family) == 0) &&
2799                     (xfrm_addr_cmp(&m[i].old_saddr, &m[i].new_saddr,
2800                                    m[i].old_family) == 0))
2801                         return -EINVAL;
2802                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
2803                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
2804                         return -EINVAL;
2805
2806                 /* check if there is any duplicated entry */
2807                 for (j = i + 1; j < num_migrate; j++) {
2808                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
2809                                     sizeof(m[i].old_daddr)) &&
2810                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
2811                                     sizeof(m[i].old_saddr)) &&
2812                             m[i].proto == m[j].proto &&
2813                             m[i].mode == m[j].mode &&
2814                             m[i].reqid == m[j].reqid &&
2815                             m[i].old_family == m[j].old_family)
2816                                 return -EINVAL;
2817                 }
2818         }
2819
2820         return 0;
2821 }
2822
2823 int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
2824                  struct xfrm_migrate *m, int num_migrate,
2825                  struct xfrm_kmaddress *k)
2826 {
2827         int i, err, nx_cur = 0, nx_new = 0;
2828         struct xfrm_policy *pol = NULL;
2829         struct xfrm_state *x, *xc;
2830         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
2831         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
2832         struct xfrm_migrate *mp;
2833
2834         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
2835                 goto out;
2836
2837         /* Stage 1 - find policy */
2838         if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
2839                 err = -ENOENT;
2840                 goto out;
2841         }
2842
2843         /* Stage 2 - find and update state(s) */
2844         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
2845                 if ((x = xfrm_migrate_state_find(mp))) {
2846                         x_cur[nx_cur] = x;
2847                         nx_cur++;
2848                         if ((xc = xfrm_state_migrate(x, mp))) {
2849                                 x_new[nx_new] = xc;
2850                                 nx_new++;
2851                         } else {
2852                                 err = -ENODATA;
2853                                 goto restore_state;
2854                         }
2855                 }
2856         }
2857
2858         /* Stage 3 - update policy */
2859         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
2860                 goto restore_state;
2861
2862         /* Stage 4 - delete old state(s) */
2863         if (nx_cur) {
2864                 xfrm_states_put(x_cur, nx_cur);
2865                 xfrm_states_delete(x_cur, nx_cur);
2866         }
2867
2868         /* Stage 5 - announce */
2869         km_migrate(sel, dir, type, m, num_migrate, k);
2870
2871         xfrm_pol_put(pol);
2872
2873         return 0;
2874 out:
2875         return err;
2876
2877 restore_state:
2878         if (pol)
2879                 xfrm_pol_put(pol);
2880         if (nx_cur)
2881                 xfrm_states_put(x_cur, nx_cur);
2882         if (nx_new)
2883                 xfrm_states_delete(x_new, nx_new);
2884
2885         return err;
2886 }
2887 EXPORT_SYMBOL(xfrm_migrate);
2888 #endif