git.oblomov.eu Git - linux-2.6/blob - net/xfrm/xfrm_policy.c

   1 /*
   2  * xfrm_policy.c
   3  *
   4  * Changes:
   5  *      Mitsuru KANDA @USAGI
   6  *      Kazunori MIYAZAWA @USAGI
   7  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   8  *              IPv6 support
   9  *      Kazunori MIYAZAWA @USAGI
  10  *      YOSHIFUJI Hideaki
  11  *              Split up af-specific portion
  12  *      Derek Atkins <derek@ihtfp.com>          Add the post_input processor
  13  *
  14  */
  15
  16 #include <linux/err.h>
  17 #include <linux/slab.h>
  18 #include <linux/kmod.h>
  19 #include <linux/list.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/notifier.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/netfilter.h>
  25 #include <linux/module.h>
  26 #include <linux/cache.h>
  27 #include <linux/audit.h>
  28 #include <net/dst.h>
  29 #include <net/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 xfrmk_spdinfo *si)
 473 {
 474         read_lock_bh(&xfrm_policy_lock);
 475         si->incnt = init_net.xfrm.policy_count[XFRM_POLICY_IN];
 476         si->outcnt = init_net.xfrm.policy_count[XFRM_POLICY_OUT];
 477         si->fwdcnt = init_net.xfrm.policy_count[XFRM_POLICY_FWD];
 478         si->inscnt = init_net.xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 479         si->outscnt = init_net.xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 480         si->fwdscnt = init_net.xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 481         si->spdhcnt = init_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;
 775
 776         write_lock_bh(&xfrm_policy_lock);
 777
 778         err = xfrm_policy_flush_secctx_check(net, type, audit_info);
 779         if (err)
 780                 goto out;
 781
 782         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 783                 struct xfrm_policy *pol;
 784                 struct hlist_node *entry;
 785                 int i;
 786
 787         again1:
 788                 hlist_for_each_entry(pol, entry,
 789                                      &net->xfrm.policy_inexact[dir], bydst) {
 790                         if (pol->type != type)
 791                                 continue;
 792                         __xfrm_policy_unlink(pol, dir);
 793                         write_unlock_bh(&xfrm_policy_lock);
 794
 795                         xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
 796                                                  audit_info->sessionid,
 797                                                  audit_info->secid);
 798
 799                         xfrm_policy_kill(pol);
 800
 801                         write_lock_bh(&xfrm_policy_lock);
 802                         goto again1;
 803                 }
 804
 805                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 806         again2:
 807                         hlist_for_each_entry(pol, entry,
 808                                              net->xfrm.policy_bydst[dir].table + i,
 809                                              bydst) {
 810                                 if (pol->type != type)
 811                                         continue;
 812                                 __xfrm_policy_unlink(pol, dir);
 813                                 write_unlock_bh(&xfrm_policy_lock);
 814
 815                                 xfrm_audit_policy_delete(pol, 1,
 816                                                          audit_info->loginuid,
 817                                                          audit_info->sessionid,
 818                                                          audit_info->secid);
 819                                 xfrm_policy_kill(pol);
 820
 821                                 write_lock_bh(&xfrm_policy_lock);
 822                                 goto again2;
 823                         }
 824                 }
 825
 826         }
 827         atomic_inc(&flow_cache_genid);
 828 out:
 829         write_unlock_bh(&xfrm_policy_lock);
 830         return err;
 831 }
 832 EXPORT_SYMBOL(xfrm_policy_flush);
 833
 834 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 835                      int (*func)(struct xfrm_policy *, int, int, void*),
 836                      void *data)
 837 {
 838         struct xfrm_policy *pol;
 839         struct xfrm_policy_walk_entry *x;
 840         int error = 0;
 841
 842         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
 843             walk->type != XFRM_POLICY_TYPE_ANY)
 844                 return -EINVAL;
 845
 846         if (list_empty(&walk->walk.all) && walk->seq != 0)
 847                 return 0;
 848
 849         write_lock_bh(&xfrm_policy_lock);
 850         if (list_empty(&walk->walk.all))
 851                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
 852         else
 853                 x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
 854         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
 855                 if (x->dead)
 856                         continue;
 857                 pol = container_of(x, struct xfrm_policy, walk);
 858                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
 859                     walk->type != pol->type)
 860                         continue;
 861                 error = func(pol, xfrm_policy_id2dir(pol->index),
 862                              walk->seq, data);
 863                 if (error) {
 864                         list_move_tail(&walk->walk.all, &x->all);
 865                         goto out;
 866                 }
 867                 walk->seq++;
 868         }
 869         if (walk->seq == 0) {
 870                 error = -ENOENT;
 871                 goto out;
 872         }
 873         list_del_init(&walk->walk.all);
 874 out:
 875         write_unlock_bh(&xfrm_policy_lock);
 876         return error;
 877 }
 878 EXPORT_SYMBOL(xfrm_policy_walk);
 879
 880 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
 881 {
 882         INIT_LIST_HEAD(&walk->walk.all);
 883         walk->walk.dead = 1;
 884         walk->type = type;
 885         walk->seq = 0;
 886 }
 887 EXPORT_SYMBOL(xfrm_policy_walk_init);
 888
 889 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk)
 890 {
 891         if (list_empty(&walk->walk.all))
 892                 return;
 893
 894         write_lock_bh(&xfrm_policy_lock);
 895         list_del(&walk->walk.all);
 896         write_unlock_bh(&xfrm_policy_lock);
 897 }
 898 EXPORT_SYMBOL(xfrm_policy_walk_done);
 899
 900 /*
 901  * Find policy to apply to this flow.
 902  *
 903  * Returns 0 if policy found, else an -errno.
 904  */
 905 static int xfrm_policy_match(struct xfrm_policy *pol, struct flowi *fl,
 906                              u8 type, u16 family, int dir)
 907 {
 908         struct xfrm_selector *sel = &pol->selector;
 909         int match, ret = -ESRCH;
 910
 911         if (pol->family != family ||
 912             pol->type != type)
 913                 return ret;
 914
 915         match = xfrm_selector_match(sel, fl, family);
 916         if (match)
 917                 ret = security_xfrm_policy_lookup(pol->security, fl->secid,
 918                                                   dir);
 919
 920         return ret;
 921 }
 922
 923 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 924                                                      struct flowi *fl,
 925                                                      u16 family, u8 dir)
 926 {
 927         int err;
 928         struct xfrm_policy *pol, *ret;
 929         xfrm_address_t *daddr, *saddr;
 930         struct hlist_node *entry;
 931         struct hlist_head *chain;
 932         u32 priority = ~0U;
 933
 934         daddr = xfrm_flowi_daddr(fl, family);
 935         saddr = xfrm_flowi_saddr(fl, family);
 936         if (unlikely(!daddr || !saddr))
 937                 return NULL;
 938
 939         read_lock_bh(&xfrm_policy_lock);
 940         chain = policy_hash_direct(net, daddr, saddr, family, dir);
 941         ret = NULL;
 942         hlist_for_each_entry(pol, entry, chain, bydst) {
 943                 err = xfrm_policy_match(pol, fl, type, family, dir);
 944                 if (err) {
 945                         if (err == -ESRCH)
 946                                 continue;
 947                         else {
 948                                 ret = ERR_PTR(err);
 949                                 goto fail;
 950                         }
 951                 } else {
 952                         ret = pol;
 953                         priority = ret->priority;
 954                         break;
 955                 }
 956         }
 957         chain = &net->xfrm.policy_inexact[dir];
 958         hlist_for_each_entry(pol, entry, chain, bydst) {
 959                 err = xfrm_policy_match(pol, fl, type, family, dir);
 960                 if (err) {
 961                         if (err == -ESRCH)
 962                                 continue;
 963                         else {
 964                                 ret = ERR_PTR(err);
 965                                 goto fail;
 966                         }
 967                 } else if (pol->priority < priority) {
 968                         ret = pol;
 969                         break;
 970                 }
 971         }
 972         if (ret)
 973                 xfrm_pol_hold(ret);
 974 fail:
 975         read_unlock_bh(&xfrm_policy_lock);
 976
 977         return ret;
 978 }
 979
 980 static int xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family,
 981                               u8 dir, void **objp, atomic_t **obj_refp)
 982 {
 983         struct xfrm_policy *pol;
 984         int err = 0;
 985
 986 #ifdef CONFIG_XFRM_SUB_POLICY
 987         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
 988         if (IS_ERR(pol)) {
 989                 err = PTR_ERR(pol);
 990                 pol = NULL;
 991         }
 992         if (pol || err)
 993                 goto end;
 994 #endif
 995         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
 996         if (IS_ERR(pol)) {
 997                 err = PTR_ERR(pol);
 998                 pol = NULL;
 999         }
1000 #ifdef CONFIG_XFRM_SUB_POLICY
1001 end:
1002 #endif
1003         if ((*objp = (void *) pol) != NULL)
1004                 *obj_refp = &pol->refcnt;
1005         return err;
1006 }
1007
1008 static inline int policy_to_flow_dir(int dir)
1009 {
1010         if (XFRM_POLICY_IN == FLOW_DIR_IN &&
1011             XFRM_POLICY_OUT == FLOW_DIR_OUT &&
1012             XFRM_POLICY_FWD == FLOW_DIR_FWD)
1013                 return dir;
1014         switch (dir) {
1015         default:
1016         case XFRM_POLICY_IN:
1017                 return FLOW_DIR_IN;
1018         case XFRM_POLICY_OUT:
1019                 return FLOW_DIR_OUT;
1020         case XFRM_POLICY_FWD:
1021                 return FLOW_DIR_FWD;
1022         }
1023 }
1024
1025 static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
1026 {
1027         struct xfrm_policy *pol;
1028
1029         read_lock_bh(&xfrm_policy_lock);
1030         if ((pol = sk->sk_policy[dir]) != NULL) {
1031                 int match = xfrm_selector_match(&pol->selector, fl,
1032                                                 sk->sk_family);
1033                 int err = 0;
1034
1035                 if (match) {
1036                         err = security_xfrm_policy_lookup(pol->security,
1037                                                       fl->secid,
1038                                                       policy_to_flow_dir(dir));
1039                         if (!err)
1040                                 xfrm_pol_hold(pol);
1041                         else if (err == -ESRCH)
1042                                 pol = NULL;
1043                         else
1044                                 pol = ERR_PTR(err);
1045                 } else
1046                         pol = NULL;
1047         }
1048         read_unlock_bh(&xfrm_policy_lock);
1049         return pol;
1050 }
1051
1052 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1053 {
1054         struct net *net = xp_net(pol);
1055         struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1056                                                      pol->family, dir);
1057
1058         list_add(&pol->walk.all, &net->xfrm.policy_all);
1059         hlist_add_head(&pol->bydst, chain);
1060         hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1061         net->xfrm.policy_count[dir]++;
1062         xfrm_pol_hold(pol);
1063
1064         if (xfrm_bydst_should_resize(net, dir, NULL))
1065                 schedule_work(&net->xfrm.policy_hash_work);
1066 }
1067
1068 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1069                                                 int dir)
1070 {
1071         struct net *net = xp_net(pol);
1072
1073         if (hlist_unhashed(&pol->bydst))
1074                 return NULL;
1075
1076         hlist_del(&pol->bydst);
1077         hlist_del(&pol->byidx);
1078         list_del(&pol->walk.all);
1079         net->xfrm.policy_count[dir]--;
1080
1081         return pol;
1082 }
1083
1084 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1085 {
1086         write_lock_bh(&xfrm_policy_lock);
1087         pol = __xfrm_policy_unlink(pol, dir);
1088         write_unlock_bh(&xfrm_policy_lock);
1089         if (pol) {
1090                 if (dir < XFRM_POLICY_MAX)
1091                         atomic_inc(&flow_cache_genid);
1092                 xfrm_policy_kill(pol);
1093                 return 0;
1094         }
1095         return -ENOENT;
1096 }
1097 EXPORT_SYMBOL(xfrm_policy_delete);
1098
1099 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1100 {
1101         struct net *net = xp_net(pol);
1102         struct xfrm_policy *old_pol;
1103
1104 #ifdef CONFIG_XFRM_SUB_POLICY
1105         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1106                 return -EINVAL;
1107 #endif
1108
1109         write_lock_bh(&xfrm_policy_lock);
1110         old_pol = sk->sk_policy[dir];
1111         sk->sk_policy[dir] = pol;
1112         if (pol) {
1113                 pol->curlft.add_time = get_seconds();
1114                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir);
1115                 __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1116         }
1117         if (old_pol)
1118                 __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1119         write_unlock_bh(&xfrm_policy_lock);
1120
1121         if (old_pol) {
1122                 xfrm_policy_kill(old_pol);
1123         }
1124         return 0;
1125 }
1126
1127 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
1128 {
1129         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1130
1131         if (newp) {
1132                 newp->selector = old->selector;
1133                 if (security_xfrm_policy_clone(old->security,
1134                                                &newp->security)) {
1135                         kfree(newp);
1136                         return NULL;  /* ENOMEM */
1137                 }
1138                 newp->lft = old->lft;
1139                 newp->curlft = old->curlft;
1140                 newp->action = old->action;
1141                 newp->flags = old->flags;
1142                 newp->xfrm_nr = old->xfrm_nr;
1143                 newp->index = old->index;
1144                 newp->type = old->type;
1145                 memcpy(newp->xfrm_vec, old->xfrm_vec,
1146                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1147                 write_lock_bh(&xfrm_policy_lock);
1148                 __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1149                 write_unlock_bh(&xfrm_policy_lock);
1150                 xfrm_pol_put(newp);
1151         }
1152         return newp;
1153 }
1154
1155 int __xfrm_sk_clone_policy(struct sock *sk)
1156 {
1157         struct xfrm_policy *p0 = sk->sk_policy[0],
1158                            *p1 = sk->sk_policy[1];
1159
1160         sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1161         if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1162                 return -ENOMEM;
1163         if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1164                 return -ENOMEM;
1165         return 0;
1166 }
1167
1168 static int
1169 xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1170                unsigned short family)
1171 {
1172         int err;
1173         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1174
1175         if (unlikely(afinfo == NULL))
1176                 return -EINVAL;
1177         err = afinfo->get_saddr(net, local, remote);
1178         xfrm_policy_put_afinfo(afinfo);
1179         return err;
1180 }
1181
1182 /* Resolve list of templates for the flow, given policy. */
1183
1184 static int
1185 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, struct flowi *fl,
1186                       struct xfrm_state **xfrm,
1187                       unsigned short family)
1188 {
1189         struct net *net = xp_net(policy);
1190         int nx;
1191         int i, error;
1192         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1193         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1194         xfrm_address_t tmp;
1195
1196         for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1197                 struct xfrm_state *x;
1198                 xfrm_address_t *remote = daddr;
1199                 xfrm_address_t *local  = saddr;
1200                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1201
1202                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
1203                     tmpl->mode == XFRM_MODE_BEET) {
1204                         remote = &tmpl->id.daddr;
1205                         local = &tmpl->saddr;
1206                         family = tmpl->encap_family;
1207                         if (xfrm_addr_any(local, family)) {
1208                                 error = xfrm_get_saddr(net, &tmp, remote, family);
1209                                 if (error)
1210                                         goto fail;
1211                                 local = &tmp;
1212                         }
1213                 }
1214
1215                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1216
1217                 if (x && x->km.state == XFRM_STATE_VALID) {
1218                         xfrm[nx++] = x;
1219                         daddr = remote;
1220                         saddr = local;
1221                         continue;
1222                 }
1223                 if (x) {
1224                         error = (x->km.state == XFRM_STATE_ERROR ?
1225                                  -EINVAL : -EAGAIN);
1226                         xfrm_state_put(x);
1227                 }
1228                 else if (error == -ESRCH)
1229                         error = -EAGAIN;
1230
1231                 if (!tmpl->optional)
1232                         goto fail;
1233         }
1234         return nx;
1235
1236 fail:
1237         for (nx--; nx>=0; nx--)
1238                 xfrm_state_put(xfrm[nx]);
1239         return error;
1240 }
1241
1242 static int
1243 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
1244                   struct xfrm_state **xfrm,
1245                   unsigned short family)
1246 {
1247         struct xfrm_state *tp[XFRM_MAX_DEPTH];
1248         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1249         int cnx = 0;
1250         int error;
1251         int ret;
1252         int i;
1253
1254         for (i = 0; i < npols; i++) {
1255                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1256                         error = -ENOBUFS;
1257                         goto fail;
1258                 }
1259
1260                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1261                 if (ret < 0) {
1262                         error = ret;
1263                         goto fail;
1264                 } else
1265                         cnx += ret;
1266         }
1267
1268         /* found states are sorted for outbound processing */
1269         if (npols > 1)
1270                 xfrm_state_sort(xfrm, tpp, cnx, family);
1271
1272         return cnx;
1273
1274  fail:
1275         for (cnx--; cnx>=0; cnx--)
1276                 xfrm_state_put(tpp[cnx]);
1277         return error;
1278
1279 }
1280
1281 /* Check that the bundle accepts the flow and its components are
1282  * still valid.
1283  */
1284
1285 static struct dst_entry *
1286 xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family)
1287 {
1288         struct dst_entry *x;
1289         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1290         if (unlikely(afinfo == NULL))
1291                 return ERR_PTR(-EINVAL);
1292         x = afinfo->find_bundle(fl, policy);
1293         xfrm_policy_put_afinfo(afinfo);
1294         return x;
1295 }
1296
1297 static inline int xfrm_get_tos(struct flowi *fl, int family)
1298 {
1299         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1300         int tos;
1301
1302         if (!afinfo)
1303                 return -EINVAL;
1304
1305         tos = afinfo->get_tos(fl);
1306
1307         xfrm_policy_put_afinfo(afinfo);
1308
1309         return tos;
1310 }
1311
1312 static inline struct xfrm_dst *xfrm_alloc_dst(int family)
1313 {
1314         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1315         struct xfrm_dst *xdst;
1316
1317         if (!afinfo)
1318                 return ERR_PTR(-EINVAL);
1319
1320         xdst = dst_alloc(afinfo->dst_ops) ?: ERR_PTR(-ENOBUFS);
1321
1322         xfrm_policy_put_afinfo(afinfo);
1323
1324         return xdst;
1325 }
1326
1327 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1328                                  int nfheader_len)
1329 {
1330         struct xfrm_policy_afinfo *afinfo =
1331                 xfrm_policy_get_afinfo(dst->ops->family);
1332         int err;
1333
1334         if (!afinfo)
1335                 return -EINVAL;
1336
1337         err = afinfo->init_path(path, dst, nfheader_len);
1338
1339         xfrm_policy_put_afinfo(afinfo);
1340
1341         return err;
1342 }
1343
1344 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev)
1345 {
1346         struct xfrm_policy_afinfo *afinfo =
1347                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1348         int err;
1349
1350         if (!afinfo)
1351                 return -EINVAL;
1352
1353         err = afinfo->fill_dst(xdst, dev);
1354
1355         xfrm_policy_put_afinfo(afinfo);
1356
1357         return err;
1358 }
1359
1360 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
1361  * all the metrics... Shortly, bundle a bundle.
1362  */
1363
1364 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1365                                             struct xfrm_state **xfrm, int nx,
1366                                             struct flowi *fl,
1367                                             struct dst_entry *dst)
1368 {
1369         unsigned long now = jiffies;
1370         struct net_device *dev;
1371         struct dst_entry *dst_prev = NULL;
1372         struct dst_entry *dst0 = NULL;
1373         int i = 0;
1374         int err;
1375         int header_len = 0;
1376         int nfheader_len = 0;
1377         int trailer_len = 0;
1378         int tos;
1379         int family = policy->selector.family;
1380         xfrm_address_t saddr, daddr;
1381
1382         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1383
1384         tos = xfrm_get_tos(fl, family);
1385         err = tos;
1386         if (tos < 0)
1387                 goto put_states;
1388
1389         dst_hold(dst);
1390
1391         for (; i < nx; i++) {
1392                 struct xfrm_dst *xdst = xfrm_alloc_dst(family);
1393                 struct dst_entry *dst1 = &xdst->u.dst;
1394
1395                 err = PTR_ERR(xdst);
1396                 if (IS_ERR(xdst)) {
1397                         dst_release(dst);
1398                         goto put_states;
1399                 }
1400
1401                 if (!dst_prev)
1402                         dst0 = dst1;
1403                 else {
1404                         dst_prev->child = dst_clone(dst1);
1405                         dst1->flags |= DST_NOHASH;
1406                 }
1407
1408                 xdst->route = dst;
1409                 memcpy(&dst1->metrics, &dst->metrics, sizeof(dst->metrics));
1410
1411                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1412                         family = xfrm[i]->props.family;
1413                         dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1414                                               family);
1415                         err = PTR_ERR(dst);
1416                         if (IS_ERR(dst))
1417                                 goto put_states;
1418                 } else
1419                         dst_hold(dst);
1420
1421                 dst1->xfrm = xfrm[i];
1422                 xdst->genid = xfrm[i]->genid;
1423
1424                 dst1->obsolete = -1;
1425                 dst1->flags |= DST_HOST;
1426                 dst1->lastuse = now;
1427
1428                 dst1->input = dst_discard;
1429                 dst1->output = xfrm[i]->outer_mode->afinfo->output;
1430
1431                 dst1->next = dst_prev;
1432                 dst_prev = dst1;
1433
1434                 header_len += xfrm[i]->props.header_len;
1435                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1436                         nfheader_len += xfrm[i]->props.header_len;
1437                 trailer_len += xfrm[i]->props.trailer_len;
1438         }
1439
1440         dst_prev->child = dst;
1441         dst0->path = dst;
1442
1443         err = -ENODEV;
1444         dev = dst->dev;
1445         if (!dev)
1446                 goto free_dst;
1447
1448         /* Copy neighbout for reachability confirmation */
1449         dst0->neighbour = neigh_clone(dst->neighbour);
1450
1451         xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1452         xfrm_init_pmtu(dst_prev);
1453
1454         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1455                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1456
1457                 err = xfrm_fill_dst(xdst, dev);
1458                 if (err)
1459                         goto free_dst;
1460
1461                 dst_prev->header_len = header_len;
1462                 dst_prev->trailer_len = trailer_len;
1463                 header_len -= xdst->u.dst.xfrm->props.header_len;
1464                 trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1465         }
1466
1467 out:
1468         return dst0;
1469
1470 put_states:
1471         for (; i < nx; i++)
1472                 xfrm_state_put(xfrm[i]);
1473 free_dst:
1474         if (dst0)
1475                 dst_free(dst0);
1476         dst0 = ERR_PTR(err);
1477         goto out;
1478 }
1479
1480 static int inline
1481 xfrm_dst_alloc_copy(void **target, void *src, int size)
1482 {
1483         if (!*target) {
1484                 *target = kmalloc(size, GFP_ATOMIC);
1485                 if (!*target)
1486                         return -ENOMEM;
1487         }
1488         memcpy(*target, src, size);
1489         return 0;
1490 }
1491
1492 static int inline
1493 xfrm_dst_update_parent(struct dst_entry *dst, struct xfrm_selector *sel)
1494 {
1495 #ifdef CONFIG_XFRM_SUB_POLICY
1496         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1497         return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1498                                    sel, sizeof(*sel));
1499 #else
1500         return 0;
1501 #endif
1502 }
1503
1504 static int inline
1505 xfrm_dst_update_origin(struct dst_entry *dst, struct flowi *fl)
1506 {
1507 #ifdef CONFIG_XFRM_SUB_POLICY
1508         struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1509         return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1510 #else
1511         return 0;
1512 #endif
1513 }
1514
1515 static int stale_bundle(struct dst_entry *dst);
1516
1517 /* Main function: finds/creates a bundle for given flow.
1518  *
1519  * At the moment we eat a raw IP route. Mostly to speed up lookups
1520  * on interfaces with disabled IPsec.
1521  */
1522 int __xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
1523                   struct sock *sk, int flags)
1524 {
1525         struct xfrm_policy *policy;
1526         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1527         int npols;
1528         int pol_dead;
1529         int xfrm_nr;
1530         int pi;
1531         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1532         struct dst_entry *dst, *dst_orig = *dst_p;
1533         int nx = 0;
1534         int err;
1535         u32 genid;
1536         u16 family;
1537         u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
1538
1539 restart:
1540         genid = atomic_read(&flow_cache_genid);
1541         policy = NULL;
1542         for (pi = 0; pi < ARRAY_SIZE(pols); pi++)
1543                 pols[pi] = NULL;
1544         npols = 0;
1545         pol_dead = 0;
1546         xfrm_nr = 0;
1547
1548         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
1549                 policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
1550                 err = PTR_ERR(policy);
1551                 if (IS_ERR(policy)) {
1552                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1553                         goto dropdst;
1554                 }
1555         }
1556
1557         if (!policy) {
1558                 /* To accelerate a bit...  */
1559                 if ((dst_orig->flags & DST_NOXFRM) ||
1560                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
1561                         goto nopol;
1562
1563                 policy = flow_cache_lookup(net, fl, dst_orig->ops->family,
1564                                            dir, xfrm_policy_lookup);
1565                 err = PTR_ERR(policy);
1566                 if (IS_ERR(policy)) {
1567                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1568                         goto dropdst;
1569                 }
1570         }
1571
1572         if (!policy)
1573                 goto nopol;
1574
1575         family = dst_orig->ops->family;
1576         pols[0] = policy;
1577         npols ++;
1578         xfrm_nr += pols[0]->xfrm_nr;
1579
1580         err = -ENOENT;
1581         if ((flags & XFRM_LOOKUP_ICMP) && !(policy->flags & XFRM_POLICY_ICMP))
1582                 goto error;
1583
1584         policy->curlft.use_time = get_seconds();
1585
1586         switch (policy->action) {
1587         default:
1588         case XFRM_POLICY_BLOCK:
1589                 /* Prohibit the flow */
1590                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
1591                 err = -EPERM;
1592                 goto error;
1593
1594         case XFRM_POLICY_ALLOW:
1595 #ifndef CONFIG_XFRM_SUB_POLICY
1596                 if (policy->xfrm_nr == 0) {
1597                         /* Flow passes not transformed. */
1598                         xfrm_pol_put(policy);
1599                         return 0;
1600                 }
1601 #endif
1602
1603                 /* Try to find matching bundle.
1604                  *
1605                  * LATER: help from flow cache. It is optional, this
1606                  * is required only for output policy.
1607                  */
1608                 dst = xfrm_find_bundle(fl, policy, family);
1609                 if (IS_ERR(dst)) {
1610                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1611                         err = PTR_ERR(dst);
1612                         goto error;
1613                 }
1614
1615                 if (dst)
1616                         break;
1617
1618 #ifdef CONFIG_XFRM_SUB_POLICY
1619                 if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1620                         pols[1] = xfrm_policy_lookup_bytype(net,
1621                                                             XFRM_POLICY_TYPE_MAIN,
1622                                                             fl, family,
1623                                                             XFRM_POLICY_OUT);
1624                         if (pols[1]) {
1625                                 if (IS_ERR(pols[1])) {
1626                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1627                                         err = PTR_ERR(pols[1]);
1628                                         goto error;
1629                                 }
1630                                 if (pols[1]->action == XFRM_POLICY_BLOCK) {
1631                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
1632                                         err = -EPERM;
1633                                         goto error;
1634                                 }
1635                                 npols ++;
1636                                 xfrm_nr += pols[1]->xfrm_nr;
1637                         }
1638                 }
1639
1640                 /*
1641                  * Because neither flowi nor bundle information knows about
1642                  * transformation template size. On more than one policy usage
1643                  * we can realize whether all of them is bypass or not after
1644                  * they are searched. See above not-transformed bypass
1645                  * is surrounded by non-sub policy configuration, too.
1646                  */
1647                 if (xfrm_nr == 0) {
1648                         /* Flow passes not transformed. */
1649                         xfrm_pols_put(pols, npols);
1650                         return 0;
1651                 }
1652
1653 #endif
1654                 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1655
1656                 if (unlikely(nx<0)) {
1657                         err = nx;
1658                         if (err == -EAGAIN && net->xfrm.sysctl_larval_drop) {
1659                                 /* EREMOTE tells the caller to generate
1660                                  * a one-shot blackhole route.
1661                                  */
1662                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1663                                 xfrm_pol_put(policy);
1664                                 return -EREMOTE;
1665                         }
1666                         if (err == -EAGAIN && (flags & XFRM_LOOKUP_WAIT)) {
1667                                 DECLARE_WAITQUEUE(wait, current);
1668
1669                                 add_wait_queue(&net->xfrm.km_waitq, &wait);
1670                                 set_current_state(TASK_INTERRUPTIBLE);
1671                                 schedule();
1672                                 set_current_state(TASK_RUNNING);
1673                                 remove_wait_queue(&net->xfrm.km_waitq, &wait);
1674
1675                                 nx = xfrm_tmpl_resolve(pols, npols, fl, xfrm, family);
1676
1677                                 if (nx == -EAGAIN && signal_pending(current)) {
1678                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1679                                         err = -ERESTART;
1680                                         goto error;
1681                                 }
1682                                 if (nx == -EAGAIN ||
1683                                     genid != atomic_read(&flow_cache_genid)) {
1684                                         xfrm_pols_put(pols, npols);
1685                                         goto restart;
1686                                 }
1687                                 err = nx;
1688                         }
1689                         if (err < 0) {
1690                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1691                                 goto error;
1692                         }
1693                 }
1694                 if (nx == 0) {
1695                         /* Flow passes not transformed. */
1696                         xfrm_pols_put(pols, npols);
1697                         return 0;
1698                 }
1699
1700                 dst = xfrm_bundle_create(policy, xfrm, nx, fl, dst_orig);
1701                 err = PTR_ERR(dst);
1702                 if (IS_ERR(dst)) {
1703                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1704                         goto error;
1705                 }
1706
1707                 for (pi = 0; pi < npols; pi++) {
1708                         read_lock_bh(&pols[pi]->lock);
1709                         pol_dead |= pols[pi]->walk.dead;
1710                         read_unlock_bh(&pols[pi]->lock);
1711                 }
1712
1713                 write_lock_bh(&policy->lock);
1714                 if (unlikely(pol_dead || stale_bundle(dst))) {
1715                         /* Wow! While we worked on resolving, this
1716                          * policy has gone. Retry. It is not paranoia,
1717                          * we just cannot enlist new bundle to dead object.
1718                          * We can't enlist stable bundles either.
1719                          */
1720                         write_unlock_bh(&policy->lock);
1721                         dst_free(dst);
1722
1723                         if (pol_dead)
1724                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLDEAD);
1725                         else
1726                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1727                         err = -EHOSTUNREACH;
1728                         goto error;
1729                 }
1730
1731                 if (npols > 1)
1732                         err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1733                 else
1734                         err = xfrm_dst_update_origin(dst, fl);
1735                 if (unlikely(err)) {
1736                         write_unlock_bh(&policy->lock);
1737                         dst_free(dst);
1738                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1739                         goto error;
1740                 }
1741
1742                 dst->next = policy->bundles;
1743                 policy->bundles = dst;
1744                 dst_hold(dst);
1745                 write_unlock_bh(&policy->lock);
1746         }
1747         *dst_p = dst;
1748         dst_release(dst_orig);
1749         xfrm_pols_put(pols, npols);
1750         return 0;
1751
1752 error:
1753         xfrm_pols_put(pols, npols);
1754 dropdst:
1755         dst_release(dst_orig);
1756         *dst_p = NULL;
1757         return err;
1758
1759 nopol:
1760         err = -ENOENT;
1761         if (flags & XFRM_LOOKUP_ICMP)
1762                 goto dropdst;
1763         return 0;
1764 }
1765 EXPORT_SYMBOL(__xfrm_lookup);
1766
1767 int xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
1768                 struct sock *sk, int flags)
1769 {
1770         int err = __xfrm_lookup(net, dst_p, fl, sk, flags);
1771
1772         if (err == -EREMOTE) {
1773                 dst_release(*dst_p);
1774                 *dst_p = NULL;
1775                 err = -EAGAIN;
1776         }
1777
1778         return err;
1779 }
1780 EXPORT_SYMBOL(xfrm_lookup);
1781
1782 static inline int
1783 xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
1784 {
1785         struct xfrm_state *x;
1786
1787         if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1788                 return 0;
1789         x = skb->sp->xvec[idx];
1790         if (!x->type->reject)
1791                 return 0;
1792         return x->type->reject(x, skb, fl);
1793 }
1794
1795 /* When skb is transformed back to its "native" form, we have to
1796  * check policy restrictions. At the moment we make this in maximally
1797  * stupid way. Shame on me. :-) Of course, connected sockets must
1798  * have policy cached at them.
1799  */
1800
1801 static inline int
1802 xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
1803               unsigned short family)
1804 {
1805         if (xfrm_state_kern(x))
1806                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
1807         return  x->id.proto == tmpl->id.proto &&
1808                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1809                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1810                 x->props.mode == tmpl->mode &&
1811                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
1812                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1813                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
1814                   xfrm_state_addr_cmp(tmpl, x, family));
1815 }
1816
1817 /*
1818  * 0 or more than 0 is returned when validation is succeeded (either bypass
1819  * because of optional transport mode, or next index of the mathced secpath
1820  * state with the template.
1821  * -1 is returned when no matching template is found.
1822  * Otherwise "-2 - errored_index" is returned.
1823  */
1824 static inline int
1825 xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
1826                unsigned short family)
1827 {
1828         int idx = start;
1829
1830         if (tmpl->optional) {
1831                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
1832                         return start;
1833         } else
1834                 start = -1;
1835         for (; idx < sp->len; idx++) {
1836                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
1837                         return ++idx;
1838                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
1839                         if (start == -1)
1840                                 start = -2-idx;
1841                         break;
1842                 }
1843         }
1844         return start;
1845 }
1846
1847 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1848                           unsigned int family, int reverse)
1849 {
1850         struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1851         int err;
1852
1853         if (unlikely(afinfo == NULL))
1854                 return -EAFNOSUPPORT;
1855
1856         afinfo->decode_session(skb, fl, reverse);
1857         err = security_xfrm_decode_session(skb, &fl->secid);
1858         xfrm_policy_put_afinfo(afinfo);
1859         return err;
1860 }
1861 EXPORT_SYMBOL(__xfrm_decode_session);
1862
1863 static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
1864 {
1865         for (; k < sp->len; k++) {
1866                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
1867                         *idxp = k;
1868                         return 1;
1869                 }
1870         }
1871
1872         return 0;
1873 }
1874
1875 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
1876                         unsigned short family)
1877 {
1878         struct net *net = dev_net(skb->dev);
1879         struct xfrm_policy *pol;
1880         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1881         int npols = 0;
1882         int xfrm_nr;
1883         int pi;
1884         int reverse;
1885         struct flowi fl;
1886         u8 fl_dir;
1887         int xerr_idx = -1;
1888
1889         reverse = dir & ~XFRM_POLICY_MASK;
1890         dir &= XFRM_POLICY_MASK;
1891         fl_dir = policy_to_flow_dir(dir);
1892
1893         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
1894                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
1895                 return 0;
1896         }
1897
1898         nf_nat_decode_session(skb, &fl, family);
1899
1900         /* First, check used SA against their selectors. */
1901         if (skb->sp) {
1902                 int i;
1903
1904                 for (i=skb->sp->len-1; i>=0; i--) {
1905                         struct xfrm_state *x = skb->sp->xvec[i];
1906                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
1907                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
1908                                 return 0;
1909                         }
1910                 }
1911         }
1912
1913         pol = NULL;
1914         if (sk && sk->sk_policy[dir]) {
1915                 pol = xfrm_sk_policy_lookup(sk, dir, &fl);
1916                 if (IS_ERR(pol)) {
1917                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
1918                         return 0;
1919                 }
1920         }
1921
1922         if (!pol)
1923                 pol = flow_cache_lookup(net, &fl, family, fl_dir,
1924                                         xfrm_policy_lookup);
1925
1926         if (IS_ERR(pol)) {
1927                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
1928                 return 0;
1929         }
1930
1931         if (!pol) {
1932                 if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
1933                         xfrm_secpath_reject(xerr_idx, skb, &fl);
1934                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
1935                         return 0;
1936                 }
1937                 return 1;
1938         }
1939
1940         pol->curlft.use_time = get_seconds();
1941
1942         pols[0] = pol;
1943         npols ++;
1944 #ifdef CONFIG_XFRM_SUB_POLICY
1945         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1946                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
1947                                                     &fl, family,
1948                                                     XFRM_POLICY_IN);
1949                 if (pols[1]) {
1950                         if (IS_ERR(pols[1])) {
1951                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
1952                                 return 0;
1953                         }
1954                         pols[1]->curlft.use_time = get_seconds();
1955                         npols ++;
1956                 }
1957         }
1958 #endif
1959
1960         if (pol->action == XFRM_POLICY_ALLOW) {
1961                 struct sec_path *sp;
1962                 static struct sec_path dummy;
1963                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
1964                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
1965                 struct xfrm_tmpl **tpp = tp;
1966                 int ti = 0;
1967                 int i, k;
1968
1969                 if ((sp = skb->sp) == NULL)
1970                         sp = &dummy;
1971
1972                 for (pi = 0; pi < npols; pi++) {
1973                         if (pols[pi] != pol &&
1974                             pols[pi]->action != XFRM_POLICY_ALLOW) {
1975                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
1976                                 goto reject;
1977                         }
1978                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
1979                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
1980                                 goto reject_error;
1981                         }
1982                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
1983                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
1984                 }
1985                 xfrm_nr = ti;
1986                 if (npols > 1) {
1987                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
1988                         tpp = stp;
1989                 }
1990
1991                 /* For each tunnel xfrm, find the first matching tmpl.
1992                  * For each tmpl before that, find corresponding xfrm.
1993                  * Order is _important_. Later we will implement
1994                  * some barriers, but at the moment barriers
1995                  * are implied between each two transformations.
1996                  */
1997                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
1998                         k = xfrm_policy_ok(tpp[i], sp, k, family);
1999                         if (k < 0) {
2000                                 if (k < -1)
2001                                         /* "-2 - errored_index" returned */
2002                                         xerr_idx = -(2+k);
2003                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2004                                 goto reject;
2005                         }
2006                 }
2007
2008                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2009                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2010                         goto reject;
2011                 }
2012
2013                 xfrm_pols_put(pols, npols);
2014                 return 1;
2015         }
2016         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2017
2018 reject:
2019         xfrm_secpath_reject(xerr_idx, skb, &fl);
2020 reject_error:
2021         xfrm_pols_put(pols, npols);
2022         return 0;
2023 }
2024 EXPORT_SYMBOL(__xfrm_policy_check);
2025
2026 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2027 {
2028         struct net *net = dev_net(skb->dev);
2029         struct flowi fl;
2030
2031         if (xfrm_decode_session(skb, &fl, family) < 0) {
2032                 /* XXX: we should have something like FWDHDRERROR here. */
2033                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2034                 return 0;
2035         }
2036
2037         return xfrm_lookup(net, &skb->dst, &fl, NULL, 0) == 0;
2038 }
2039 EXPORT_SYMBOL(__xfrm_route_forward);
2040
2041 /* Optimize later using cookies and generation ids. */
2042
2043 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2044 {
2045         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2046          * to "-1" to force all XFRM destinations to get validated by
2047          * dst_ops->check on every use.  We do this because when a
2048          * normal route referenced by an XFRM dst is obsoleted we do
2049          * not go looking around for all parent referencing XFRM dsts
2050          * so that we can invalidate them.  It is just too much work.
2051          * Instead we make the checks here on every use.  For example:
2052          *
2053          *      XFRM dst A --> IPv4 dst X
2054          *
2055          * X is the "xdst->route" of A (X is also the "dst->path" of A
2056          * in this example).  If X is marked obsolete, "A" will not
2057          * notice.  That's what we are validating here via the
2058          * stale_bundle() check.
2059          *
2060          * When a policy's bundle is pruned, we dst_free() the XFRM
2061          * dst which causes it's ->obsolete field to be set to a
2062          * positive non-zero integer.  If an XFRM dst has been pruned
2063          * like this, we want to force a new route lookup.
2064          */
2065         if (dst->obsolete < 0 && !stale_bundle(dst))
2066                 return dst;
2067
2068         return NULL;
2069 }
2070
2071 static int stale_bundle(struct dst_entry *dst)
2072 {
2073         return !xfrm_bundle_ok(NULL, (struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
2074 }
2075
2076 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2077 {
2078         while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2079                 dst->dev = dev_net(dev)->loopback_dev;
2080                 dev_hold(dst->dev);
2081                 dev_put(dev);
2082         }
2083 }
2084 EXPORT_SYMBOL(xfrm_dst_ifdown);
2085
2086 static void xfrm_link_failure(struct sk_buff *skb)
2087 {
2088         /* Impossible. Such dst must be popped before reaches point of failure. */
2089         return;
2090 }
2091
2092 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2093 {
2094         if (dst) {
2095                 if (dst->obsolete) {
2096                         dst_release(dst);
2097                         dst = NULL;
2098                 }
2099         }
2100         return dst;
2101 }
2102
2103 static void prune_one_bundle(struct xfrm_policy *pol, int (*func)(struct dst_entry *), struct dst_entry **gc_list_p)
2104 {
2105         struct dst_entry *dst, **dstp;
2106
2107         write_lock(&pol->lock);
2108         dstp = &pol->bundles;
2109         while ((dst=*dstp) != NULL) {
2110                 if (func(dst)) {
2111                         *dstp = dst->next;
2112                         dst->next = *gc_list_p;
2113                         *gc_list_p = dst;
2114                 } else {
2115                         dstp = &dst->next;
2116                 }
2117         }
2118         write_unlock(&pol->lock);
2119 }
2120
2121 static void xfrm_prune_bundles(struct net *net, int (*func)(struct dst_entry *))
2122 {
2123         struct dst_entry *gc_list = NULL;
2124         int dir;
2125
2126         read_lock_bh(&xfrm_policy_lock);
2127         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2128                 struct xfrm_policy *pol;
2129                 struct hlist_node *entry;
2130                 struct hlist_head *table;
2131                 int i;
2132
2133                 hlist_for_each_entry(pol, entry,
2134                                      &net->xfrm.policy_inexact[dir], bydst)
2135                         prune_one_bundle(pol, func, &gc_list);
2136
2137                 table = net->xfrm.policy_bydst[dir].table;
2138                 for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
2139                         hlist_for_each_entry(pol, entry, table + i, bydst)
2140                                 prune_one_bundle(pol, func, &gc_list);
2141                 }
2142         }
2143         read_unlock_bh(&xfrm_policy_lock);
2144
2145         while (gc_list) {
2146                 struct dst_entry *dst = gc_list;
2147                 gc_list = dst->next;
2148                 dst_free(dst);
2149         }
2150 }
2151
2152 static int unused_bundle(struct dst_entry *dst)
2153 {
2154         return !atomic_read(&dst->__refcnt);
2155 }
2156
2157 static void __xfrm_garbage_collect(struct net *net)
2158 {
2159         xfrm_prune_bundles(net, unused_bundle);
2160 }
2161
2162 static int xfrm_flush_bundles(struct net *net)
2163 {
2164         xfrm_prune_bundles(net, stale_bundle);
2165         return 0;
2166 }
2167
2168 static void xfrm_init_pmtu(struct dst_entry *dst)
2169 {
2170         do {
2171                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2172                 u32 pmtu, route_mtu_cached;
2173
2174                 pmtu = dst_mtu(dst->child);
2175                 xdst->child_mtu_cached = pmtu;
2176
2177                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2178
2179                 route_mtu_cached = dst_mtu(xdst->route);
2180                 xdst->route_mtu_cached = route_mtu_cached;
2181
2182                 if (pmtu > route_mtu_cached)
2183                         pmtu = route_mtu_cached;
2184
2185                 dst->metrics[RTAX_MTU-1] = pmtu;
2186         } while ((dst = dst->next));
2187 }
2188
2189 /* Check that the bundle accepts the flow and its components are
2190  * still valid.
2191  */
2192
2193 int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
2194                 struct flowi *fl, int family, int strict)
2195 {
2196         struct dst_entry *dst = &first->u.dst;
2197         struct xfrm_dst *last;
2198         u32 mtu;
2199
2200         if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2201             (dst->dev && !netif_running(dst->dev)))
2202                 return 0;
2203 #ifdef CONFIG_XFRM_SUB_POLICY
2204         if (fl) {
2205                 if (first->origin && !flow_cache_uli_match(first->origin, fl))
2206                         return 0;
2207                 if (first->partner &&
2208                     !xfrm_selector_match(first->partner, fl, family))
2209                         return 0;
2210         }
2211 #endif
2212
2213         last = NULL;
2214
2215         do {
2216                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2217
2218                 if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
2219                         return 0;
2220                 if (fl && pol &&
2221                     !security_xfrm_state_pol_flow_match(dst->xfrm, pol, fl))
2222                         return 0;
2223                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
2224                         return 0;
2225                 if (xdst->genid != dst->xfrm->genid)
2226                         return 0;
2227
2228                 if (strict && fl &&
2229                     !(dst->xfrm->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
2230                     !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
2231                         return 0;
2232
2233                 mtu = dst_mtu(dst->child);
2234                 if (xdst->child_mtu_cached != mtu) {
2235                         last = xdst;
2236                         xdst->child_mtu_cached = mtu;
2237                 }
2238
2239                 if (!dst_check(xdst->route, xdst->route_cookie))
2240                         return 0;
2241                 mtu = dst_mtu(xdst->route);
2242                 if (xdst->route_mtu_cached != mtu) {
2243                         last = xdst;
2244                         xdst->route_mtu_cached = mtu;
2245                 }
2246
2247                 dst = dst->child;
2248         } while (dst->xfrm);
2249
2250         if (likely(!last))
2251                 return 1;
2252
2253         mtu = last->child_mtu_cached;
2254         for (;;) {
2255                 dst = &last->u.dst;
2256
2257                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
2258                 if (mtu > last->route_mtu_cached)
2259                         mtu = last->route_mtu_cached;
2260                 dst->metrics[RTAX_MTU-1] = mtu;
2261
2262                 if (last == first)
2263                         break;
2264
2265                 last = (struct xfrm_dst *)last->u.dst.next;
2266                 last->child_mtu_cached = mtu;
2267         }
2268
2269         return 1;
2270 }
2271
2272 EXPORT_SYMBOL(xfrm_bundle_ok);
2273
2274 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2275 {
2276         int err = 0;
2277         if (unlikely(afinfo == NULL))
2278                 return -EINVAL;
2279         if (unlikely(afinfo->family >= NPROTO))
2280                 return -EAFNOSUPPORT;
2281         write_lock_bh(&xfrm_policy_afinfo_lock);
2282         if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2283                 err = -ENOBUFS;
2284         else {
2285                 struct dst_ops *dst_ops = afinfo->dst_ops;
2286                 if (likely(dst_ops->kmem_cachep == NULL))
2287                         dst_ops->kmem_cachep = xfrm_dst_cache;
2288                 if (likely(dst_ops->check == NULL))
2289                         dst_ops->check = xfrm_dst_check;
2290                 if (likely(dst_ops->negative_advice == NULL))
2291                         dst_ops->negative_advice = xfrm_negative_advice;
2292                 if (likely(dst_ops->link_failure == NULL))
2293                         dst_ops->link_failure = xfrm_link_failure;
2294                 if (likely(afinfo->garbage_collect == NULL))
2295                         afinfo->garbage_collect = __xfrm_garbage_collect;
2296                 xfrm_policy_afinfo[afinfo->family] = afinfo;
2297         }
2298         write_unlock_bh(&xfrm_policy_afinfo_lock);
2299         return err;
2300 }
2301 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2302
2303 int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2304 {
2305         int err = 0;
2306         if (unlikely(afinfo == NULL))
2307                 return -EINVAL;
2308         if (unlikely(afinfo->family >= NPROTO))
2309                 return -EAFNOSUPPORT;
2310         write_lock_bh(&xfrm_policy_afinfo_lock);
2311         if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2312                 if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2313                         err = -EINVAL;
2314                 else {
2315                         struct dst_ops *dst_ops = afinfo->dst_ops;
2316                         xfrm_policy_afinfo[afinfo->family] = NULL;
2317                         dst_ops->kmem_cachep = NULL;
2318                         dst_ops->check = NULL;
2319                         dst_ops->negative_advice = NULL;
2320                         dst_ops->link_failure = NULL;
2321                         afinfo->garbage_collect = NULL;
2322                 }
2323         }
2324         write_unlock_bh(&xfrm_policy_afinfo_lock);
2325         return err;
2326 }
2327 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2328
2329 static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
2330 {
2331         struct xfrm_policy_afinfo *afinfo;
2332         if (unlikely(family >= NPROTO))
2333                 return NULL;
2334         read_lock(&xfrm_policy_afinfo_lock);
2335         afinfo = xfrm_policy_afinfo[family];
2336         if (unlikely(!afinfo))
2337                 read_unlock(&xfrm_policy_afinfo_lock);
2338         return afinfo;
2339 }
2340
2341 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
2342 {
2343         read_unlock(&xfrm_policy_afinfo_lock);
2344 }
2345
2346 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2347 {
2348         struct net_device *dev = ptr;
2349
2350         switch (event) {
2351         case NETDEV_DOWN:
2352                 xfrm_flush_bundles(dev_net(dev));
2353         }
2354         return NOTIFY_DONE;
2355 }
2356
2357 static struct notifier_block xfrm_dev_notifier = {
2358         .notifier_call  = xfrm_dev_event,
2359 };
2360
2361 #ifdef CONFIG_XFRM_STATISTICS
2362 static int __net_init xfrm_statistics_init(struct net *net)
2363 {
2364         int rv;
2365
2366         if (snmp_mib_init((void **)net->mib.xfrm_statistics,
2367                           sizeof(struct linux_xfrm_mib)) < 0)
2368                 return -ENOMEM;
2369         rv = xfrm_proc_init(net);
2370         if (rv < 0)
2371                 snmp_mib_free((void **)net->mib.xfrm_statistics);
2372         return rv;
2373 }
2374
2375 static void xfrm_statistics_fini(struct net *net)
2376 {
2377         xfrm_proc_fini(net);
2378         snmp_mib_free((void **)net->mib.xfrm_statistics);
2379 }
2380 #else
2381 static int __net_init xfrm_statistics_init(struct net *net)
2382 {
2383         return 0;
2384 }
2385
2386 static void xfrm_statistics_fini(struct net *net)
2387 {
2388 }
2389 #endif
2390
2391 static int __net_init xfrm_policy_init(struct net *net)
2392 {
2393         unsigned int hmask, sz;
2394         int dir;
2395
2396         if (net_eq(net, &init_net))
2397                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2398                                            sizeof(struct xfrm_dst),
2399                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2400                                            NULL);
2401
2402         hmask = 8 - 1;
2403         sz = (hmask+1) * sizeof(struct hlist_head);
2404
2405         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2406         if (!net->xfrm.policy_byidx)
2407                 goto out_byidx;
2408         net->xfrm.policy_idx_hmask = hmask;
2409
2410         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2411                 struct xfrm_policy_hash *htab;
2412
2413                 net->xfrm.policy_count[dir] = 0;
2414                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2415
2416                 htab = &net->xfrm.policy_bydst[dir];
2417                 htab->table = xfrm_hash_alloc(sz);
2418                 if (!htab->table)
2419                         goto out_bydst;
2420                 htab->hmask = hmask;
2421         }
2422
2423         INIT_LIST_HEAD(&net->xfrm.policy_all);
2424         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2425         if (net_eq(net, &init_net))
2426                 register_netdevice_notifier(&xfrm_dev_notifier);
2427         return 0;
2428
2429 out_bydst:
2430         for (dir--; dir >= 0; dir--) {
2431                 struct xfrm_policy_hash *htab;
2432
2433                 htab = &net->xfrm.policy_bydst[dir];
2434                 xfrm_hash_free(htab->table, sz);
2435         }
2436         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2437 out_byidx:
2438         return -ENOMEM;
2439 }
2440
2441 static void xfrm_policy_fini(struct net *net)
2442 {
2443         struct xfrm_audit audit_info;
2444         unsigned int sz;
2445         int dir;
2446
2447         flush_work(&net->xfrm.policy_hash_work);
2448 #ifdef CONFIG_XFRM_SUB_POLICY
2449         audit_info.loginuid = -1;
2450         audit_info.sessionid = -1;
2451         audit_info.secid = 0;
2452         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info);
2453 #endif
2454         audit_info.loginuid = -1;
2455         audit_info.sessionid = -1;
2456         audit_info.secid = 0;
2457         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info);
2458         flush_work(&xfrm_policy_gc_work);
2459
2460         WARN_ON(!list_empty(&net->xfrm.policy_all));
2461
2462         for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2463                 struct xfrm_policy_hash *htab;
2464
2465                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2466
2467                 htab = &net->xfrm.policy_bydst[dir];
2468                 sz = (htab->hmask + 1);
2469                 WARN_ON(!hlist_empty(htab->table));
2470                 xfrm_hash_free(htab->table, sz);
2471         }
2472
2473         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2474         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2475         xfrm_hash_free(net->xfrm.policy_byidx, sz);
2476 }
2477
2478 static int __net_init xfrm_net_init(struct net *net)
2479 {
2480         int rv;
2481
2482         rv = xfrm_statistics_init(net);
2483         if (rv < 0)
2484                 goto out_statistics;
2485         rv = xfrm_state_init(net);
2486         if (rv < 0)
2487                 goto out_state;
2488         rv = xfrm_policy_init(net);
2489         if (rv < 0)
2490                 goto out_policy;
2491         rv = xfrm_sysctl_init(net);
2492         if (rv < 0)
2493                 goto out_sysctl;
2494         return 0;
2495
2496 out_sysctl:
2497         xfrm_policy_fini(net);
2498 out_policy:
2499         xfrm_state_fini(net);
2500 out_state:
2501         xfrm_statistics_fini(net);
2502 out_statistics:
2503         return rv;
2504 }
2505
2506 static void __net_exit xfrm_net_exit(struct net *net)
2507 {
2508         xfrm_sysctl_fini(net);
2509         xfrm_policy_fini(net);
2510         xfrm_state_fini(net);
2511         xfrm_statistics_fini(net);
2512 }
2513
2514 static struct pernet_operations __net_initdata xfrm_net_ops = {
2515         .init = xfrm_net_init,
2516         .exit = xfrm_net_exit,
2517 };
2518
2519 void __init xfrm_init(void)
2520 {
2521         register_pernet_subsys(&xfrm_net_ops);
2522         xfrm_input_init();
2523 }
2524
2525 #ifdef CONFIG_AUDITSYSCALL
2526 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2527                                          struct audit_buffer *audit_buf)
2528 {
2529         struct xfrm_sec_ctx *ctx = xp->security;
2530         struct xfrm_selector *sel = &xp->selector;
2531
2532         if (ctx)
2533                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2534                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2535
2536         switch(sel->family) {
2537         case AF_INET:
2538                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2539                 if (sel->prefixlen_s != 32)
2540                         audit_log_format(audit_buf, " src_prefixlen=%d",
2541                                          sel->prefixlen_s);
2542                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2543                 if (sel->prefixlen_d != 32)
2544                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2545                                          sel->prefixlen_d);
2546                 break;
2547         case AF_INET6:
2548                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
2549                 if (sel->prefixlen_s != 128)
2550                         audit_log_format(audit_buf, " src_prefixlen=%d",
2551                                          sel->prefixlen_s);
2552                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
2553                 if (sel->prefixlen_d != 128)
2554                         audit_log_format(audit_buf, " dst_prefixlen=%d",
2555                                          sel->prefixlen_d);
2556                 break;
2557         }
2558 }
2559
2560 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2561                            uid_t auid, u32 sessionid, u32 secid)
2562 {
2563         struct audit_buffer *audit_buf;
2564
2565         audit_buf = xfrm_audit_start("SPD-add");
2566         if (audit_buf == NULL)
2567                 return;
2568         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2569         audit_log_format(audit_buf, " res=%u", result);
2570         xfrm_audit_common_policyinfo(xp, audit_buf);
2571         audit_log_end(audit_buf);
2572 }
2573 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
2574
2575 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
2576                               uid_t auid, u32 sessionid, u32 secid)
2577 {
2578         struct audit_buffer *audit_buf;
2579
2580         audit_buf = xfrm_audit_start("SPD-delete");
2581         if (audit_buf == NULL)
2582                 return;
2583         xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2584         audit_log_format(audit_buf, " res=%u", result);
2585         xfrm_audit_common_policyinfo(xp, audit_buf);
2586         audit_log_end(audit_buf);
2587 }
2588 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
2589 #endif
2590
2591 #ifdef CONFIG_XFRM_MIGRATE
2592 static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
2593                                        struct xfrm_selector *sel_tgt)
2594 {
2595         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
2596                 if (sel_tgt->family == sel_cmp->family &&
2597                     xfrm_addr_cmp(&sel_tgt->daddr, &sel_cmp->daddr,
2598                                   sel_cmp->family) == 0 &&
2599                     xfrm_addr_cmp(&sel_tgt->saddr, &sel_cmp->saddr,
2600                                   sel_cmp->family) == 0 &&
2601                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
2602                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
2603                         return 1;
2604                 }
2605         } else {
2606                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
2607                         return 1;
2608                 }
2609         }
2610         return 0;
2611 }
2612
2613 static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
2614                                                      u8 dir, u8 type)
2615 {
2616         struct xfrm_policy *pol, *ret = NULL;
2617         struct hlist_node *entry;
2618         struct hlist_head *chain;
2619         u32 priority = ~0U;
2620
2621         read_lock_bh(&xfrm_policy_lock);
2622         chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir);
2623         hlist_for_each_entry(pol, entry, chain, bydst) {
2624                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2625                     pol->type == type) {
2626                         ret = pol;
2627                         priority = ret->priority;
2628                         break;
2629                 }
2630         }
2631         chain = &init_net.xfrm.policy_inexact[dir];
2632         hlist_for_each_entry(pol, entry, chain, bydst) {
2633                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2634                     pol->type == type &&
2635                     pol->priority < priority) {
2636                         ret = pol;
2637                         break;
2638                 }
2639         }
2640
2641         if (ret)
2642                 xfrm_pol_hold(ret);
2643
2644         read_unlock_bh(&xfrm_policy_lock);
2645
2646         return ret;
2647 }
2648
2649 static int migrate_tmpl_match(struct xfrm_migrate *m, struct xfrm_tmpl *t)
2650 {
2651         int match = 0;
2652
2653         if (t->mode == m->mode && t->id.proto == m->proto &&
2654             (m->reqid == 0 || t->reqid == m->reqid)) {
2655                 switch (t->mode) {
2656                 case XFRM_MODE_TUNNEL:
2657                 case XFRM_MODE_BEET:
2658                         if (xfrm_addr_cmp(&t->id.daddr, &m->old_daddr,
2659                                           m->old_family) == 0 &&
2660                             xfrm_addr_cmp(&t->saddr, &m->old_saddr,
2661                                           m->old_family) == 0) {
2662                                 match = 1;
2663                         }
2664                         break;
2665                 case XFRM_MODE_TRANSPORT:
2666                         /* in case of transport mode, template does not store
2667                            any IP addresses, hence we just compare mode and
2668                            protocol */
2669                         match = 1;
2670                         break;
2671                 default:
2672                         break;
2673                 }
2674         }
2675         return match;
2676 }
2677
2678 /* update endpoint address(es) of template(s) */
2679 static int xfrm_policy_migrate(struct xfrm_policy *pol,
2680                                struct xfrm_migrate *m, int num_migrate)
2681 {
2682         struct xfrm_migrate *mp;
2683         struct dst_entry *dst;
2684         int i, j, n = 0;
2685
2686         write_lock_bh(&pol->lock);
2687         if (unlikely(pol->walk.dead)) {
2688                 /* target policy has been deleted */
2689                 write_unlock_bh(&pol->lock);
2690                 return -ENOENT;
2691         }
2692
2693         for (i = 0; i < pol->xfrm_nr; i++) {
2694                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
2695                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
2696                                 continue;
2697                         n++;
2698                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
2699                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
2700                                 continue;
2701                         /* update endpoints */
2702                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
2703                                sizeof(pol->xfrm_vec[i].id.daddr));
2704                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
2705                                sizeof(pol->xfrm_vec[i].saddr));
2706                         pol->xfrm_vec[i].encap_family = mp->new_family;
2707                         /* flush bundles */
2708                         while ((dst = pol->bundles) != NULL) {
2709                                 pol->bundles = dst->next;
2710                                 dst_free(dst);
2711                         }
2712                 }
2713         }
2714
2715         write_unlock_bh(&pol->lock);
2716
2717         if (!n)
2718                 return -ENODATA;
2719
2720         return 0;
2721 }
2722
2723 static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
2724 {
2725         int i, j;
2726
2727         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
2728                 return -EINVAL;
2729
2730         for (i = 0; i < num_migrate; i++) {
2731                 if ((xfrm_addr_cmp(&m[i].old_daddr, &m[i].new_daddr,
2732                                    m[i].old_family) == 0) &&
2733                     (xfrm_addr_cmp(&m[i].old_saddr, &m[i].new_saddr,
2734                                    m[i].old_family) == 0))
2735                         return -EINVAL;
2736                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
2737                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
2738                         return -EINVAL;
2739
2740                 /* check if there is any duplicated entry */
2741                 for (j = i + 1; j < num_migrate; j++) {
2742                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
2743                                     sizeof(m[i].old_daddr)) &&
2744                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
2745                                     sizeof(m[i].old_saddr)) &&
2746                             m[i].proto == m[j].proto &&
2747                             m[i].mode == m[j].mode &&
2748                             m[i].reqid == m[j].reqid &&
2749                             m[i].old_family == m[j].old_family)
2750                                 return -EINVAL;
2751                 }
2752         }
2753
2754         return 0;
2755 }
2756
2757 int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
2758                  struct xfrm_migrate *m, int num_migrate,
2759                  struct xfrm_kmaddress *k)
2760 {
2761         int i, err, nx_cur = 0, nx_new = 0;
2762         struct xfrm_policy *pol = NULL;
2763         struct xfrm_state *x, *xc;
2764         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
2765         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
2766         struct xfrm_migrate *mp;
2767
2768         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
2769                 goto out;
2770
2771         /* Stage 1 - find policy */
2772         if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
2773                 err = -ENOENT;
2774                 goto out;
2775         }
2776
2777         /* Stage 2 - find and update state(s) */
2778         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
2779                 if ((x = xfrm_migrate_state_find(mp))) {
2780                         x_cur[nx_cur] = x;
2781                         nx_cur++;
2782                         if ((xc = xfrm_state_migrate(x, mp))) {
2783                                 x_new[nx_new] = xc;
2784                                 nx_new++;
2785                         } else {
2786                                 err = -ENODATA;
2787                                 goto restore_state;
2788                         }
2789                 }
2790         }
2791
2792         /* Stage 3 - update policy */
2793         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
2794                 goto restore_state;
2795
2796         /* Stage 4 - delete old state(s) */
2797         if (nx_cur) {
2798                 xfrm_states_put(x_cur, nx_cur);
2799                 xfrm_states_delete(x_cur, nx_cur);
2800         }
2801
2802         /* Stage 5 - announce */
2803         km_migrate(sel, dir, type, m, num_migrate, k);
2804
2805         xfrm_pol_put(pol);
2806
2807         return 0;
2808 out:
2809         return err;
2810
2811 restore_state:
2812         if (pol)
2813                 xfrm_pol_put(pol);
2814         if (nx_cur)
2815                 xfrm_states_put(x_cur, nx_cur);
2816         if (nx_new)
2817                 xfrm_states_delete(x_new, nx_new);
2818
2819         return err;
2820 }
2821 EXPORT_SYMBOL(xfrm_migrate);
2822 #endif