net/xfrm/xfrm_policy.c

   1 /*
   2  * xfrm_policy.c
   3  *
   4  * Changes:
   5  *      Mitsuru KANDA @USAGI
   6  *      Kazunori MIYAZAWA @USAGI
   7  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   8  *              IPv6 support
   9  *      Kazunori MIYAZAWA @USAGI
  10  *      YOSHIFUJI Hideaki
  11  *              Split up af-specific portion
  12  *      Derek Atkins <derek@ihtfp.com>          Add the post_input processor
  13  *
  14  */
  15
  16 #include <linux/err.h>
  17 #include <linux/slab.h>
  18 #include <linux/kmod.h>
  19 #include <linux/list.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/notifier.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/netfilter.h>
  25 #include <linux/module.h>
  26 #include <linux/cache.h>
  27 #include <linux/cpu.h>
  28 #include <linux/audit.h>
  29 #include <linux/rhashtable.h>
  30 #include <linux/if_tunnel.h>
  31 #include <net/dst.h>
  32 #include <net/flow.h>
  33 #include <net/xfrm.h>
  34 #include <net/ip.h>
  35 #if IS_ENABLED(CONFIG_IPV6_MIP6)
  36 #include <net/mip6.h>
  37 #endif
  38 #ifdef CONFIG_XFRM_STATISTICS
  39 #include <net/snmp.h>
  40 #endif
  41
  42 #include "xfrm_hash.h"
  43
  44 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  45 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  46 #define XFRM_MAX_QUEUE_LEN      100
  47
  48 struct xfrm_flo {
  49         struct dst_entry *dst_orig;
  50         u8 flags;
  51 };
  52
  53 /* prefixes smaller than this are stored in lists, not trees. */
  54 #define INEXACT_PREFIXLEN_IPV4  16
  55 #define INEXACT_PREFIXLEN_IPV6  48
  56
  57 struct xfrm_pol_inexact_node {
  58         struct rb_node node;
  59         union {
  60                 xfrm_address_t addr;
  61                 struct rcu_head rcu;
  62         };
  63         u8 prefixlen;
  64
  65         struct rb_root root;
  66
  67         /* the policies matching this node, can be empty list */
  68         struct hlist_head hhead;
  69 };
  70
  71 /* xfrm inexact policy search tree:
  72  * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
  73  *  |
  74  * +---- root_d: sorted by daddr:prefix
  75  * |                 |
  76  * |        xfrm_pol_inexact_node
  77  * |                 |
  78  * |                 +- root: sorted by saddr/prefix
  79  * |                 |              |
  80  * |                 |         xfrm_pol_inexact_node
  81  * |                 |              |
  82  * |                 |              + root: unused
  83  * |                 |              |
  84  * |                 |              + hhead: saddr:daddr policies
  85  * |                 |
  86  * |                 +- coarse policies and all any:daddr policies
  87  * |
  88  * +---- root_s: sorted by saddr:prefix
  89  * |                 |
  90  * |        xfrm_pol_inexact_node
  91  * |                 |
  92  * |                 + root: unused
  93  * |                 |
  94  * |                 + hhead: saddr:any policies
  95  * |
  96  * +---- coarse policies and all any:any policies
  97  *
  98  * Lookups return four candidate lists:
  99  * 1. any:any list from top-level xfrm_pol_inexact_bin
 100  * 2. any:daddr list from daddr tree
 101  * 3. saddr:daddr list from 2nd level daddr tree
 102  * 4. saddr:any list from saddr tree
 103  *
 104  * This result set then needs to be searched for the policy with
 105  * the lowest priority.  If two results have same prio, youngest one wins.
 106  */
 107
 108 struct xfrm_pol_inexact_key {
 109         possible_net_t net;
 110         u32 if_id;
 111         u16 family;
 112         u8 dir, type;
 113 };
 114
 115 struct xfrm_pol_inexact_bin {
 116         struct xfrm_pol_inexact_key k;
 117         struct rhash_head head;
 118         /* list containing '*:*' policies */
 119         struct hlist_head hhead;
 120
 121         seqcount_t count;
 122         /* tree sorted by daddr/prefix */
 123         struct rb_root root_d;
 124
 125         /* tree sorted by saddr/prefix */
 126         struct rb_root root_s;
 127
 128         /* slow path below */
 129         struct list_head inexact_bins;
 130         struct rcu_head rcu;
 131 };
 132
 133 enum xfrm_pol_inexact_candidate_type {
 134         XFRM_POL_CAND_BOTH,
 135         XFRM_POL_CAND_SADDR,
 136         XFRM_POL_CAND_DADDR,
 137         XFRM_POL_CAND_ANY,
 138
 139         XFRM_POL_CAND_MAX,
 140 };
 141
 142 struct xfrm_pol_inexact_candidates {
 143         struct hlist_head *res[XFRM_POL_CAND_MAX];
 144 };
 145
 146 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
 147 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
 148
 149 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
 150 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 151                                                 __read_mostly;
 152
 153 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
 154 static __read_mostly seqcount_t xfrm_policy_hash_generation;
 155
 156 static struct rhashtable xfrm_policy_inexact_table;
 157 static const struct rhashtable_params xfrm_pol_inexact_params;
 158
 159 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
 160 static int stale_bundle(struct dst_entry *dst);
 161 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
 162 static void xfrm_policy_queue_process(struct timer_list *t);
 163
 164 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 165 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 166                                                 int dir);
 167
 168 static struct xfrm_pol_inexact_bin *
 169 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
 170                            u32 if_id);
 171
 172 static struct xfrm_pol_inexact_bin *
 173 xfrm_policy_inexact_lookup_rcu(struct net *net,
 174                                u8 type, u16 family, u8 dir, u32 if_id);
 175 static struct xfrm_policy *
 176 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
 177                         bool excl);
 178 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
 179                                             struct xfrm_policy *policy);
 180
 181 static bool
 182 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
 183                                     struct xfrm_pol_inexact_bin *b,
 184                                     const xfrm_address_t *saddr,
 185                                     const xfrm_address_t *daddr);
 186
 187 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
 188 {
 189         return refcount_inc_not_zero(&policy->refcnt);
 190 }
 191
 192 static inline bool
 193 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 194 {
 195         const struct flowi4 *fl4 = &fl->u.ip4;
 196
 197         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
 198                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
 199                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
 200                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
 201                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
 202                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 203 }
 204
 205 static inline bool
 206 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 207 {
 208         const struct flowi6 *fl6 = &fl->u.ip6;
 209
 210         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
 211                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
 212                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
 213                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
 214                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
 215                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 216 }
 217
 218 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
 219                          unsigned short family)
 220 {
 221         switch (family) {
 222         case AF_INET:
 223                 return __xfrm4_selector_match(sel, fl);
 224         case AF_INET6:
 225                 return __xfrm6_selector_match(sel, fl);
 226         }
 227         return false;
 228 }
 229
 230 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 231 {
 232         const struct xfrm_policy_afinfo *afinfo;
 233
 234         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 235                 return NULL;
 236         rcu_read_lock();
 237         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 238         if (unlikely(!afinfo))
 239                 rcu_read_unlock();
 240         return afinfo;
 241 }
 242
 243 /* Called with rcu_read_lock(). */
 244 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 245 {
 246         return rcu_dereference(xfrm_if_cb);
 247 }
 248
 249 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 250                                     const xfrm_address_t *saddr,
 251                                     const xfrm_address_t *daddr,
 252                                     int family, u32 mark)
 253 {
 254         const struct xfrm_policy_afinfo *afinfo;
 255         struct dst_entry *dst;
 256
 257         afinfo = xfrm_policy_get_afinfo(family);
 258         if (unlikely(afinfo == NULL))
 259                 return ERR_PTR(-EAFNOSUPPORT);
 260
 261         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 262
 263         rcu_read_unlock();
 264
 265         return dst;
 266 }
 267 EXPORT_SYMBOL(__xfrm_dst_lookup);
 268
 269 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 270                                                 int tos, int oif,
 271                                                 xfrm_address_t *prev_saddr,
 272                                                 xfrm_address_t *prev_daddr,
 273                                                 int family, u32 mark)
 274 {
 275         struct net *net = xs_net(x);
 276         xfrm_address_t *saddr = &x->props.saddr;
 277         xfrm_address_t *daddr = &x->id.daddr;
 278         struct dst_entry *dst;
 279
 280         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 281                 saddr = x->coaddr;
 282                 daddr = prev_daddr;
 283         }
 284         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 285                 saddr = prev_saddr;
 286                 daddr = x->coaddr;
 287         }
 288
 289         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 290
 291         if (!IS_ERR(dst)) {
 292                 if (prev_saddr != saddr)
 293                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 294                 if (prev_daddr != daddr)
 295                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 296         }
 297
 298         return dst;
 299 }
 300
 301 static inline unsigned long make_jiffies(long secs)
 302 {
 303         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 304                 return MAX_SCHEDULE_TIMEOUT-1;
 305         else
 306                 return secs*HZ;
 307 }
 308
 309 static void xfrm_policy_timer(struct timer_list *t)
 310 {
 311         struct xfrm_policy *xp = from_timer(xp, t, timer);
 312         time64_t now = ktime_get_real_seconds();
 313         time64_t next = TIME64_MAX;
 314         int warn = 0;
 315         int dir;
 316
 317         read_lock(&xp->lock);
 318
 319         if (unlikely(xp->walk.dead))
 320                 goto out;
 321
 322         dir = xfrm_policy_id2dir(xp->index);
 323
 324         if (xp->lft.hard_add_expires_seconds) {
 325                 time64_t tmo = xp->lft.hard_add_expires_seconds +
 326                         xp->curlft.add_time - now;
 327                 if (tmo <= 0)
 328                         goto expired;
 329                 if (tmo < next)
 330                         next = tmo;
 331         }
 332         if (xp->lft.hard_use_expires_seconds) {
 333                 time64_t tmo = xp->lft.hard_use_expires_seconds +
 334                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 335                 if (tmo <= 0)
 336                         goto expired;
 337                 if (tmo < next)
 338                         next = tmo;
 339         }
 340         if (xp->lft.soft_add_expires_seconds) {
 341                 time64_t tmo = xp->lft.soft_add_expires_seconds +
 342                         xp->curlft.add_time - now;
 343                 if (tmo <= 0) {
 344                         warn = 1;
 345                         tmo = XFRM_KM_TIMEOUT;
 346                 }
 347                 if (tmo < next)
 348                         next = tmo;
 349         }
 350         if (xp->lft.soft_use_expires_seconds) {
 351                 time64_t tmo = xp->lft.soft_use_expires_seconds +
 352                         (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 353                 if (tmo <= 0) {
 354                         warn = 1;
 355                         tmo = XFRM_KM_TIMEOUT;
 356                 }
 357                 if (tmo < next)
 358                         next = tmo;
 359         }
 360
 361         if (warn)
 362                 km_policy_expired(xp, dir, 0, 0);
 363         if (next != TIME64_MAX &&
 364             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 365                 xfrm_pol_hold(xp);
 366
 367 out:
 368         read_unlock(&xp->lock);
 369         xfrm_pol_put(xp);
 370         return;
 371
 372 expired:
 373         read_unlock(&xp->lock);
 374         if (!xfrm_policy_delete(xp, dir))
 375                 km_policy_expired(xp, dir, 1, 0);
 376         xfrm_pol_put(xp);
 377 }
 378
 379 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 380  * SPD calls.
 381  */
 382
 383 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 384 {
 385         struct xfrm_policy *policy;
 386
 387         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 388
 389         if (policy) {
 390                 write_pnet(&policy->xp_net, net);
 391                 INIT_LIST_HEAD(&policy->walk.all);
 392                 INIT_HLIST_NODE(&policy->bydst_inexact_list);
 393                 INIT_HLIST_NODE(&policy->bydst);
 394                 INIT_HLIST_NODE(&policy->byidx);
 395                 rwlock_init(&policy->lock);
 396                 refcount_set(&policy->refcnt, 1);
 397                 skb_queue_head_init(&policy->polq.hold_queue);
 398                 timer_setup(&policy->timer, xfrm_policy_timer, 0);
 399                 timer_setup(&policy->polq.hold_timer,
 400                             xfrm_policy_queue_process, 0);
 401         }
 402         return policy;
 403 }
 404 EXPORT_SYMBOL(xfrm_policy_alloc);
 405
 406 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 407 {
 408         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 409
 410         security_xfrm_policy_free(policy->security);
 411         kfree(policy);
 412 }
 413
 414 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 415
 416 void xfrm_policy_destroy(struct xfrm_policy *policy)
 417 {
 418         BUG_ON(!policy->walk.dead);
 419
 420         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 421                 BUG();
 422
 423         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 424 }
 425 EXPORT_SYMBOL(xfrm_policy_destroy);
 426
 427 /* Rule must be locked. Release descendant resources, announce
 428  * entry dead. The rule must be unlinked from lists to the moment.
 429  */
 430
 431 static void xfrm_policy_kill(struct xfrm_policy *policy)
 432 {
 433         policy->walk.dead = 1;
 434
 435         atomic_inc(&policy->genid);
 436
 437         if (del_timer(&policy->polq.hold_timer))
 438                 xfrm_pol_put(policy);
 439         skb_queue_purge(&policy->polq.hold_queue);
 440
 441         if (del_timer(&policy->timer))
 442                 xfrm_pol_put(policy);
 443
 444         xfrm_pol_put(policy);
 445 }
 446
 447 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 448
 449 static inline unsigned int idx_hash(struct net *net, u32 index)
 450 {
 451         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 452 }
 453
 454 /* calculate policy hash thresholds */
 455 static void __get_hash_thresh(struct net *net,
 456                               unsigned short family, int dir,
 457                               u8 *dbits, u8 *sbits)
 458 {
 459         switch (family) {
 460         case AF_INET:
 461                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 462                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 463                 break;
 464
 465         case AF_INET6:
 466                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 467                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 468                 break;
 469
 470         default:
 471                 *dbits = 0;
 472                 *sbits = 0;
 473         }
 474 }
 475
 476 static struct hlist_head *policy_hash_bysel(struct net *net,
 477                                             const struct xfrm_selector *sel,
 478                                             unsigned short family, int dir)
 479 {
 480         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 481         unsigned int hash;
 482         u8 dbits;
 483         u8 sbits;
 484
 485         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 486         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 487
 488         if (hash == hmask + 1)
 489                 return NULL;
 490
 491         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 492                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 493 }
 494
 495 static struct hlist_head *policy_hash_direct(struct net *net,
 496                                              const xfrm_address_t *daddr,
 497                                              const xfrm_address_t *saddr,
 498                                              unsigned short family, int dir)
 499 {
 500         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 501         unsigned int hash;
 502         u8 dbits;
 503         u8 sbits;
 504
 505         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 506         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 507
 508         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 509                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 510 }
 511
 512 static void xfrm_dst_hash_transfer(struct net *net,
 513                                    struct hlist_head *list,
 514                                    struct hlist_head *ndsttable,
 515                                    unsigned int nhashmask,
 516                                    int dir)
 517 {
 518         struct hlist_node *tmp, *entry0 = NULL;
 519         struct xfrm_policy *pol;
 520         unsigned int h0 = 0;
 521         u8 dbits;
 522         u8 sbits;
 523
 524 redo:
 525         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 526                 unsigned int h;
 527
 528                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 529                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 530                                 pol->family, nhashmask, dbits, sbits);
 531                 if (!entry0) {
 532                         hlist_del_rcu(&pol->bydst);
 533                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 534                         h0 = h;
 535                 } else {
 536                         if (h != h0)
 537                                 continue;
 538                         hlist_del_rcu(&pol->bydst);
 539                         hlist_add_behind_rcu(&pol->bydst, entry0);
 540                 }
 541                 entry0 = &pol->bydst;
 542         }
 543         if (!hlist_empty(list)) {
 544                 entry0 = NULL;
 545                 goto redo;
 546         }
 547 }
 548
 549 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 550                                    struct hlist_head *nidxtable,
 551                                    unsigned int nhashmask)
 552 {
 553         struct hlist_node *tmp;
 554         struct xfrm_policy *pol;
 555
 556         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 557                 unsigned int h;
 558
 559                 h = __idx_hash(pol->index, nhashmask);
 560                 hlist_add_head(&pol->byidx, nidxtable+h);
 561         }
 562 }
 563
 564 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 565 {
 566         return ((old_hmask + 1) << 1) - 1;
 567 }
 568
 569 static void xfrm_bydst_resize(struct net *net, int dir)
 570 {
 571         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 572         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 573         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 574         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 575         struct hlist_head *odst;
 576         int i;
 577
 578         if (!ndst)
 579                 return;
 580
 581         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 582         write_seqcount_begin(&xfrm_policy_hash_generation);
 583
 584         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 585                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 586
 587         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 588                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 589
 590         for (i = hmask; i >= 0; i--)
 591                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 592
 593         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 594         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 595
 596         write_seqcount_end(&xfrm_policy_hash_generation);
 597         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 598
 599         synchronize_rcu();
 600
 601         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 602 }
 603
 604 static void xfrm_byidx_resize(struct net *net, int total)
 605 {
 606         unsigned int hmask = net->xfrm.policy_idx_hmask;
 607         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 608         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 609         struct hlist_head *oidx = net->xfrm.policy_byidx;
 610         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 611         int i;
 612
 613         if (!nidx)
 614                 return;
 615
 616         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 617
 618         for (i = hmask; i >= 0; i--)
 619                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 620
 621         net->xfrm.policy_byidx = nidx;
 622         net->xfrm.policy_idx_hmask = nhashmask;
 623
 624         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 625
 626         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 627 }
 628
 629 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 630 {
 631         unsigned int cnt = net->xfrm.policy_count[dir];
 632         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 633
 634         if (total)
 635                 *total += cnt;
 636
 637         if ((hmask + 1) < xfrm_policy_hashmax &&
 638             cnt > hmask)
 639                 return 1;
 640
 641         return 0;
 642 }
 643
 644 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 645 {
 646         unsigned int hmask = net->xfrm.policy_idx_hmask;
 647
 648         if ((hmask + 1) < xfrm_policy_hashmax &&
 649             total > hmask)
 650                 return 1;
 651
 652         return 0;
 653 }
 654
 655 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 656 {
 657         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 658         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 659         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 660         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 661         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 662         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 663         si->spdhcnt = net->xfrm.policy_idx_hmask;
 664         si->spdhmcnt = xfrm_policy_hashmax;
 665 }
 666 EXPORT_SYMBOL(xfrm_spd_getinfo);
 667
 668 static DEFINE_MUTEX(hash_resize_mutex);
 669 static void xfrm_hash_resize(struct work_struct *work)
 670 {
 671         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 672         int dir, total;
 673
 674         mutex_lock(&hash_resize_mutex);
 675
 676         total = 0;
 677         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 678                 if (xfrm_bydst_should_resize(net, dir, &total))
 679                         xfrm_bydst_resize(net, dir);
 680         }
 681         if (xfrm_byidx_should_resize(net, total))
 682                 xfrm_byidx_resize(net, total);
 683
 684         mutex_unlock(&hash_resize_mutex);
 685 }
 686
 687 /* Make sure *pol can be inserted into fastbin.
 688  * Useful to check that later insert requests will be sucessful
 689  * (provided xfrm_policy_lock is held throughout).
 690  */
 691 static struct xfrm_pol_inexact_bin *
 692 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
 693 {
 694         struct xfrm_pol_inexact_bin *bin, *prev;
 695         struct xfrm_pol_inexact_key k = {
 696                 .family = pol->family,
 697                 .type = pol->type,
 698                 .dir = dir,
 699                 .if_id = pol->if_id,
 700         };
 701         struct net *net = xp_net(pol);
 702
 703         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
 704
 705         write_pnet(&k.net, net);
 706         bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
 707                                      xfrm_pol_inexact_params);
 708         if (bin)
 709                 return bin;
 710
 711         bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
 712         if (!bin)
 713                 return NULL;
 714
 715         bin->k = k;
 716         INIT_HLIST_HEAD(&bin->hhead);
 717         bin->root_d = RB_ROOT;
 718         bin->root_s = RB_ROOT;
 719         seqcount_init(&bin->count);
 720
 721         prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
 722                                                 &bin->k, &bin->head,
 723                                                 xfrm_pol_inexact_params);
 724         if (!prev) {
 725                 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
 726                 return bin;
 727         }
 728
 729         kfree(bin);
 730
 731         return IS_ERR(prev) ? NULL : prev;
 732 }
 733
 734 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
 735                                                int family, u8 prefixlen)
 736 {
 737         if (xfrm_addr_any(addr, family))
 738                 return true;
 739
 740         if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
 741                 return true;
 742
 743         if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
 744                 return true;
 745
 746         return false;
 747 }
 748
 749 static bool
 750 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
 751 {
 752         const xfrm_address_t *addr;
 753         bool saddr_any, daddr_any;
 754         u8 prefixlen;
 755
 756         addr = &policy->selector.saddr;
 757         prefixlen = policy->selector.prefixlen_s;
 758
 759         saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 760                                                        policy->family,
 761                                                        prefixlen);
 762         addr = &policy->selector.daddr;
 763         prefixlen = policy->selector.prefixlen_d;
 764         daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 765                                                        policy->family,
 766                                                        prefixlen);
 767         return saddr_any && daddr_any;
 768 }
 769
 770 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
 771                                        const xfrm_address_t *addr, u8 prefixlen)
 772 {
 773         node->addr = *addr;
 774         node->prefixlen = prefixlen;
 775 }
 776
 777 static struct xfrm_pol_inexact_node *
 778 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
 779 {
 780         struct xfrm_pol_inexact_node *node;
 781
 782         node = kzalloc(sizeof(*node), GFP_ATOMIC);
 783         if (node)
 784                 xfrm_pol_inexact_node_init(node, addr, prefixlen);
 785
 786         return node;
 787 }
 788
 789 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
 790                                   const xfrm_address_t *b,
 791                                   u8 prefixlen, u16 family)
 792 {
 793         unsigned int pdw, pbi;
 794         int delta = 0;
 795
 796         switch (family) {
 797         case AF_INET:
 798                 if (sizeof(long) == 4 && prefixlen == 0)
 799                         return ntohl(a->a4) - ntohl(b->a4);
 800                 return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) -
 801                        (ntohl(b->a4) & ((~0UL << (32 - prefixlen))));
 802         case AF_INET6:
 803                 pdw = prefixlen >> 5;
 804                 pbi = prefixlen & 0x1f;
 805
 806                 if (pdw) {
 807                         delta = memcmp(a->a6, b->a6, pdw << 2);
 808                         if (delta)
 809                                 return delta;
 810                 }
 811                 if (pbi) {
 812                         u32 mask = ~0u << (32 - pbi);
 813
 814                         delta = (ntohl(a->a6[pdw]) & mask) -
 815                                 (ntohl(b->a6[pdw]) & mask);
 816                 }
 817                 break;
 818         default:
 819                 break;
 820         }
 821
 822         return delta;
 823 }
 824
 825 static void xfrm_policy_inexact_list_reinsert(struct net *net,
 826                                               struct xfrm_pol_inexact_node *n,
 827                                               u16 family)
 828 {
 829         unsigned int matched_s, matched_d;
 830         struct xfrm_policy *policy, *p;
 831
 832         matched_s = 0;
 833         matched_d = 0;
 834
 835         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 836                 struct hlist_node *newpos = NULL;
 837                 bool matches_s, matches_d;
 838
 839                 if (!policy->bydst_reinsert)
 840                         continue;
 841
 842                 WARN_ON_ONCE(policy->family != family);
 843
 844                 policy->bydst_reinsert = false;
 845                 hlist_for_each_entry(p, &n->hhead, bydst) {
 846                         if (policy->priority > p->priority)
 847                                 newpos = &p->bydst;
 848                         else if (policy->priority == p->priority &&
 849                                  policy->pos > p->pos)
 850                                 newpos = &p->bydst;
 851                         else
 852                                 break;
 853                 }
 854
 855                 if (newpos)
 856                         hlist_add_behind_rcu(&policy->bydst, newpos);
 857                 else
 858                         hlist_add_head_rcu(&policy->bydst, &n->hhead);
 859
 860                 /* paranoia checks follow.
 861                  * Check that the reinserted policy matches at least
 862                  * saddr or daddr for current node prefix.
 863                  *
 864                  * Matching both is fine, matching saddr in one policy
 865                  * (but not daddr) and then matching only daddr in another
 866                  * is a bug.
 867                  */
 868                 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
 869                                                    &n->addr,
 870                                                    n->prefixlen,
 871                                                    family) == 0;
 872                 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
 873                                                    &n->addr,
 874                                                    n->prefixlen,
 875                                                    family) == 0;
 876                 if (matches_s && matches_d)
 877                         continue;
 878
 879                 WARN_ON_ONCE(!matches_s && !matches_d);
 880                 if (matches_s)
 881                         matched_s++;
 882                 if (matches_d)
 883                         matched_d++;
 884                 WARN_ON_ONCE(matched_s && matched_d);
 885         }
 886 }
 887
 888 static void xfrm_policy_inexact_node_reinsert(struct net *net,
 889                                               struct xfrm_pol_inexact_node *n,
 890                                               struct rb_root *new,
 891                                               u16 family)
 892 {
 893         struct xfrm_pol_inexact_node *node;
 894         struct rb_node **p, *parent;
 895
 896         /* we should not have another subtree here */
 897         WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
 898 restart:
 899         parent = NULL;
 900         p = &new->rb_node;
 901         while (*p) {
 902                 u8 prefixlen;
 903                 int delta;
 904
 905                 parent = *p;
 906                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 907
 908                 prefixlen = min(node->prefixlen, n->prefixlen);
 909
 910                 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
 911                                                prefixlen, family);
 912                 if (delta < 0) {
 913                         p = &parent->rb_left;
 914                 } else if (delta > 0) {
 915                         p = &parent->rb_right;
 916                 } else {
 917                         struct xfrm_policy *tmp;
 918
 919                         hlist_for_each_entry(tmp, &n->hhead, bydst) {
 920                                 tmp->bydst_reinsert = true;
 921                                 hlist_del_rcu(&tmp->bydst);
 922                         }
 923
 924                         xfrm_policy_inexact_list_reinsert(net, node, family);
 925
 926                         if (node->prefixlen == n->prefixlen) {
 927                                 kfree_rcu(n, rcu);
 928                                 return;
 929                         }
 930
 931                         rb_erase(*p, new);
 932                         kfree_rcu(n, rcu);
 933                         n = node;
 934                         n->prefixlen = prefixlen;
 935                         goto restart;
 936                 }
 937         }
 938
 939         rb_link_node_rcu(&n->node, parent, p);
 940         rb_insert_color(&n->node, new);
 941 }
 942
 943 /* merge nodes v and n */
 944 static void xfrm_policy_inexact_node_merge(struct net *net,
 945                                            struct xfrm_pol_inexact_node *v,
 946                                            struct xfrm_pol_inexact_node *n,
 947                                            u16 family)
 948 {
 949         struct xfrm_pol_inexact_node *node;
 950         struct xfrm_policy *tmp;
 951         struct rb_node *rnode;
 952
 953         /* To-be-merged node v has a subtree.
 954          *
 955          * Dismantle it and insert its nodes to n->root.
 956          */
 957         while ((rnode = rb_first(&v->root)) != NULL) {
 958                 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
 959                 rb_erase(&node->node, &v->root);
 960                 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
 961                                                   family);
 962         }
 963
 964         hlist_for_each_entry(tmp, &v->hhead, bydst) {
 965                 tmp->bydst_reinsert = true;
 966                 hlist_del_rcu(&tmp->bydst);
 967         }
 968
 969         xfrm_policy_inexact_list_reinsert(net, n, family);
 970 }
 971
 972 static struct xfrm_pol_inexact_node *
 973 xfrm_policy_inexact_insert_node(struct net *net,
 974                                 struct rb_root *root,
 975                                 xfrm_address_t *addr,
 976                                 u16 family, u8 prefixlen, u8 dir)
 977 {
 978         struct xfrm_pol_inexact_node *cached = NULL;
 979         struct rb_node **p, *parent = NULL;
 980         struct xfrm_pol_inexact_node *node;
 981
 982         p = &root->rb_node;
 983         while (*p) {
 984                 int delta;
 985
 986                 parent = *p;
 987                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 988
 989                 delta = xfrm_policy_addr_delta(addr, &node->addr,
 990                                                node->prefixlen,
 991                                                family);
 992                 if (delta == 0 && prefixlen >= node->prefixlen) {
 993                         WARN_ON_ONCE(cached); /* ipsec policies got lost */
 994                         return node;
 995                 }
 996
 997                 if (delta < 0)
 998                         p = &parent->rb_left;
 999                 else
1000                         p = &parent->rb_right;
1001
1002                 if (prefixlen < node->prefixlen) {
1003                         delta = xfrm_policy_addr_delta(addr, &node->addr,
1004                                                        prefixlen,
1005                                                        family);
1006                         if (delta)
1007                                 continue;
1008
1009                         /* This node is a subnet of the new prefix. It needs
1010                          * to be removed and re-inserted with the smaller
1011                          * prefix and all nodes that are now also covered
1012                          * by the reduced prefixlen.
1013                          */
1014                         rb_erase(&node->node, root);
1015
1016                         if (!cached) {
1017                                 xfrm_pol_inexact_node_init(node, addr,
1018                                                            prefixlen);
1019                                 cached = node;
1020                         } else {
1021                                 /* This node also falls within the new
1022                                  * prefixlen. Merge the to-be-reinserted
1023                                  * node and this one.
1024                                  */
1025                                 xfrm_policy_inexact_node_merge(net, node,
1026                                                                cached, family);
1027                                 kfree_rcu(node, rcu);
1028                         }
1029
1030                         /* restart */
1031                         p = &root->rb_node;
1032                         parent = NULL;
1033                 }
1034         }
1035
1036         node = cached;
1037         if (!node) {
1038                 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1039                 if (!node)
1040                         return NULL;
1041         }
1042
1043         rb_link_node_rcu(&node->node, parent, p);
1044         rb_insert_color(&node->node, root);
1045
1046         return node;
1047 }
1048
1049 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1050 {
1051         struct xfrm_pol_inexact_node *node;
1052         struct rb_node *rn = rb_first(r);
1053
1054         while (rn) {
1055                 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1056
1057                 xfrm_policy_inexact_gc_tree(&node->root, rm);
1058                 rn = rb_next(rn);
1059
1060                 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1061                         WARN_ON_ONCE(rm);
1062                         continue;
1063                 }
1064
1065                 rb_erase(&node->node, r);
1066                 kfree_rcu(node, rcu);
1067         }
1068 }
1069
1070 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1071 {
1072         write_seqcount_begin(&b->count);
1073         xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1074         xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1075         write_seqcount_end(&b->count);
1076
1077         if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1078             !hlist_empty(&b->hhead)) {
1079                 WARN_ON_ONCE(net_exit);
1080                 return;
1081         }
1082
1083         if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1084                                    xfrm_pol_inexact_params) == 0) {
1085                 list_del(&b->inexact_bins);
1086                 kfree_rcu(b, rcu);
1087         }
1088 }
1089
1090 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1091 {
1092         struct net *net = read_pnet(&b->k.net);
1093
1094         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1095         __xfrm_policy_inexact_prune_bin(b, false);
1096         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1097 }
1098
1099 static void __xfrm_policy_inexact_flush(struct net *net)
1100 {
1101         struct xfrm_pol_inexact_bin *bin, *t;
1102
1103         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1104
1105         list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1106                 __xfrm_policy_inexact_prune_bin(bin, false);
1107 }
1108
1109 static struct hlist_head *
1110 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1111                                 struct xfrm_policy *policy, u8 dir)
1112 {
1113         struct xfrm_pol_inexact_node *n;
1114         struct net *net;
1115
1116         net = xp_net(policy);
1117         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1118
1119         if (xfrm_policy_inexact_insert_use_any_list(policy))
1120                 return &bin->hhead;
1121
1122         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1123                                                policy->family,
1124                                                policy->selector.prefixlen_d)) {
1125                 write_seqcount_begin(&bin->count);
1126                 n = xfrm_policy_inexact_insert_node(net,
1127                                                     &bin->root_s,
1128                                                     &policy->selector.saddr,
1129                                                     policy->family,
1130                                                     policy->selector.prefixlen_s,
1131                                                     dir);
1132                 write_seqcount_end(&bin->count);
1133                 if (!n)
1134                         return NULL;
1135
1136                 return &n->hhead;
1137         }
1138
1139         /* daddr is fixed */
1140         write_seqcount_begin(&bin->count);
1141         n = xfrm_policy_inexact_insert_node(net,
1142                                             &bin->root_d,
1143                                             &policy->selector.daddr,
1144                                             policy->family,
1145                                             policy->selector.prefixlen_d, dir);
1146         write_seqcount_end(&bin->count);
1147         if (!n)
1148                 return NULL;
1149
1150         /* saddr is wildcard */
1151         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1152                                                policy->family,
1153                                                policy->selector.prefixlen_s))
1154                 return &n->hhead;
1155
1156         write_seqcount_begin(&bin->count);
1157         n = xfrm_policy_inexact_insert_node(net,
1158                                             &n->root,
1159                                             &policy->selector.saddr,
1160                                             policy->family,
1161                                             policy->selector.prefixlen_s, dir);
1162         write_seqcount_end(&bin->count);
1163         if (!n)
1164                 return NULL;
1165
1166         return &n->hhead;
1167 }
1168
1169 static struct xfrm_policy *
1170 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1171 {
1172         struct xfrm_pol_inexact_bin *bin;
1173         struct xfrm_policy *delpol;
1174         struct hlist_head *chain;
1175         struct net *net;
1176
1177         bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1178         if (!bin)
1179                 return ERR_PTR(-ENOMEM);
1180
1181         net = xp_net(policy);
1182         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1183
1184         chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1185         if (!chain) {
1186                 __xfrm_policy_inexact_prune_bin(bin, false);
1187                 return ERR_PTR(-ENOMEM);
1188         }
1189
1190         delpol = xfrm_policy_insert_list(chain, policy, excl);
1191         if (delpol && excl) {
1192                 __xfrm_policy_inexact_prune_bin(bin, false);
1193                 return ERR_PTR(-EEXIST);
1194         }
1195
1196         chain = &net->xfrm.policy_inexact[dir];
1197         xfrm_policy_insert_inexact_list(chain, policy);
1198
1199         if (delpol)
1200                 __xfrm_policy_inexact_prune_bin(bin, false);
1201
1202         return delpol;
1203 }
1204
1205 static void xfrm_hash_rebuild(struct work_struct *work)
1206 {
1207         struct net *net = container_of(work, struct net,
1208                                        xfrm.policy_hthresh.work);
1209         unsigned int hmask;
1210         struct xfrm_policy *pol;
1211         struct xfrm_policy *policy;
1212         struct hlist_head *chain;
1213         struct hlist_head *odst;
1214         struct hlist_node *newpos;
1215         int i;
1216         int dir;
1217         unsigned seq;
1218         u8 lbits4, rbits4, lbits6, rbits6;
1219
1220         mutex_lock(&hash_resize_mutex);
1221
1222         /* read selector prefixlen thresholds */
1223         do {
1224                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1225
1226                 lbits4 = net->xfrm.policy_hthresh.lbits4;
1227                 rbits4 = net->xfrm.policy_hthresh.rbits4;
1228                 lbits6 = net->xfrm.policy_hthresh.lbits6;
1229                 rbits6 = net->xfrm.policy_hthresh.rbits6;
1230         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1231
1232         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1233         write_seqcount_begin(&xfrm_policy_hash_generation);
1234
1235         /* make sure that we can insert the indirect policies again before
1236          * we start with destructive action.
1237          */
1238         list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1239                 struct xfrm_pol_inexact_bin *bin;
1240                 u8 dbits, sbits;
1241
1242                 dir = xfrm_policy_id2dir(policy->index);
1243                 if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1244                         continue;
1245
1246                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1247                         if (policy->family == AF_INET) {
1248                                 dbits = rbits4;
1249                                 sbits = lbits4;
1250                         } else {
1251                                 dbits = rbits6;
1252                                 sbits = lbits6;
1253                         }
1254                 } else {
1255                         if (policy->family == AF_INET) {
1256                                 dbits = lbits4;
1257                                 sbits = rbits4;
1258                         } else {
1259                                 dbits = lbits6;
1260                                 sbits = rbits6;
1261                         }
1262                 }
1263
1264                 if (policy->selector.prefixlen_d < dbits ||
1265                     policy->selector.prefixlen_s < sbits)
1266                         continue;
1267
1268                 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1269                 if (!bin)
1270                         goto out_unlock;
1271
1272                 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1273                         goto out_unlock;
1274         }
1275
1276         /* reset the bydst and inexact table in all directions */
1277         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1278                 struct hlist_node *n;
1279
1280                 hlist_for_each_entry_safe(policy, n,
1281                                           &net->xfrm.policy_inexact[dir],
1282                                           bydst_inexact_list)
1283                         hlist_del_init(&policy->bydst_inexact_list);
1284
1285                 hmask = net->xfrm.policy_bydst[dir].hmask;
1286                 odst = net->xfrm.policy_bydst[dir].table;
1287                 for (i = hmask; i >= 0; i--)
1288                         INIT_HLIST_HEAD(odst + i);
1289                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1290                         /* dir out => dst = remote, src = local */
1291                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1292                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1293                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1294                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1295                 } else {
1296                         /* dir in/fwd => dst = local, src = remote */
1297                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1298                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1299                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1300                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1301                 }
1302         }
1303
1304         /* re-insert all policies by order of creation */
1305         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1306                 if (policy->walk.dead)
1307                         continue;
1308                 dir = xfrm_policy_id2dir(policy->index);
1309                 if (dir >= XFRM_POLICY_MAX) {
1310                         /* skip socket policies */
1311                         continue;
1312                 }
1313                 newpos = NULL;
1314                 chain = policy_hash_bysel(net, &policy->selector,
1315                                           policy->family, dir);
1316
1317                 hlist_del_rcu(&policy->bydst);
1318
1319                 if (!chain) {
1320                         void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1321
1322                         WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1323                         continue;
1324                 }
1325
1326                 hlist_for_each_entry(pol, chain, bydst) {
1327                         if (policy->priority >= pol->priority)
1328                                 newpos = &pol->bydst;
1329                         else
1330                                 break;
1331                 }
1332                 if (newpos)
1333                         hlist_add_behind_rcu(&policy->bydst, newpos);
1334                 else
1335                         hlist_add_head_rcu(&policy->bydst, chain);
1336         }
1337
1338 out_unlock:
1339         __xfrm_policy_inexact_flush(net);
1340         write_seqcount_end(&xfrm_policy_hash_generation);
1341         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1342
1343         mutex_unlock(&hash_resize_mutex);
1344 }
1345
1346 void xfrm_policy_hash_rebuild(struct net *net)
1347 {
1348         schedule_work(&net->xfrm.policy_hthresh.work);
1349 }
1350 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1351
1352 /* Generate new index... KAME seems to generate them ordered by cost
1353  * of an absolute inpredictability of ordering of rules. This will not pass. */
1354 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1355 {
1356         static u32 idx_generator;
1357
1358         for (;;) {
1359                 struct hlist_head *list;
1360                 struct xfrm_policy *p;
1361                 u32 idx;
1362                 int found;
1363
1364                 if (!index) {
1365                         idx = (idx_generator | dir);
1366                         idx_generator += 8;
1367                 } else {
1368                         idx = index;
1369                         index = 0;
1370                 }
1371
1372                 if (idx == 0)
1373                         idx = 8;
1374                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1375                 found = 0;
1376                 hlist_for_each_entry(p, list, byidx) {
1377                         if (p->index == idx) {
1378                                 found = 1;
1379                                 break;
1380                         }
1381                 }
1382                 if (!found)
1383                         return idx;
1384         }
1385 }
1386
1387 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1388 {
1389         u32 *p1 = (u32 *) s1;
1390         u32 *p2 = (u32 *) s2;
1391         int len = sizeof(struct xfrm_selector) / sizeof(u32);
1392         int i;
1393
1394         for (i = 0; i < len; i++) {
1395                 if (p1[i] != p2[i])
1396                         return 1;
1397         }
1398
1399         return 0;
1400 }
1401
1402 static void xfrm_policy_requeue(struct xfrm_policy *old,
1403                                 struct xfrm_policy *new)
1404 {
1405         struct xfrm_policy_queue *pq = &old->polq;
1406         struct sk_buff_head list;
1407
1408         if (skb_queue_empty(&pq->hold_queue))
1409                 return;
1410
1411         __skb_queue_head_init(&list);
1412
1413         spin_lock_bh(&pq->hold_queue.lock);
1414         skb_queue_splice_init(&pq->hold_queue, &list);
1415         if (del_timer(&pq->hold_timer))
1416                 xfrm_pol_put(old);
1417         spin_unlock_bh(&pq->hold_queue.lock);
1418
1419         pq = &new->polq;
1420
1421         spin_lock_bh(&pq->hold_queue.lock);
1422         skb_queue_splice(&list, &pq->hold_queue);
1423         pq->timeout = XFRM_QUEUE_TMO_MIN;
1424         if (!mod_timer(&pq->hold_timer, jiffies))
1425                 xfrm_pol_hold(new);
1426         spin_unlock_bh(&pq->hold_queue.lock);
1427 }
1428
1429 static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
1430                                    struct xfrm_policy *pol)
1431 {
1432         u32 mark = policy->mark.v & policy->mark.m;
1433
1434         if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
1435                 return true;
1436
1437         if ((mark & pol->mark.m) == pol->mark.v &&
1438             policy->priority == pol->priority)
1439                 return true;
1440
1441         return false;
1442 }
1443
1444 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1445 {
1446         const struct xfrm_pol_inexact_key *k = data;
1447         u32 a = k->type << 24 | k->dir << 16 | k->family;
1448
1449         return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1450                             seed);
1451 }
1452
1453 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1454 {
1455         const struct xfrm_pol_inexact_bin *b = data;
1456
1457         return xfrm_pol_bin_key(&b->k, 0, seed);
1458 }
1459
1460 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1461                             const void *ptr)
1462 {
1463         const struct xfrm_pol_inexact_key *key = arg->key;
1464         const struct xfrm_pol_inexact_bin *b = ptr;
1465         int ret;
1466
1467         if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1468                 return -1;
1469
1470         ret = b->k.dir ^ key->dir;
1471         if (ret)
1472                 return ret;
1473
1474         ret = b->k.type ^ key->type;
1475         if (ret)
1476                 return ret;
1477
1478         ret = b->k.family ^ key->family;
1479         if (ret)
1480                 return ret;
1481
1482         return b->k.if_id ^ key->if_id;
1483 }
1484
1485 static const struct rhashtable_params xfrm_pol_inexact_params = {
1486         .head_offset            = offsetof(struct xfrm_pol_inexact_bin, head),
1487         .hashfn                 = xfrm_pol_bin_key,
1488         .obj_hashfn             = xfrm_pol_bin_obj,
1489         .obj_cmpfn              = xfrm_pol_bin_cmp,
1490         .automatic_shrinking    = true,
1491 };
1492
1493 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1494                                             struct xfrm_policy *policy)
1495 {
1496         struct xfrm_policy *pol, *delpol = NULL;
1497         struct hlist_node *newpos = NULL;
1498         int i = 0;
1499
1500         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1501                 if (pol->type == policy->type &&
1502                     pol->if_id == policy->if_id &&
1503                     !selector_cmp(&pol->selector, &policy->selector) &&
1504                     xfrm_policy_mark_match(policy, pol) &&
1505                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1506                     !WARN_ON(delpol)) {
1507                         delpol = pol;
1508                         if (policy->priority > pol->priority)
1509                                 continue;
1510                 } else if (policy->priority >= pol->priority) {
1511                         newpos = &pol->bydst_inexact_list;
1512                         continue;
1513                 }
1514                 if (delpol)
1515                         break;
1516         }
1517
1518         if (newpos)
1519                 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1520         else
1521                 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1522
1523         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1524                 pol->pos = i;
1525                 i++;
1526         }
1527 }
1528
1529 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1530                                                    struct xfrm_policy *policy,
1531                                                    bool excl)
1532 {
1533         struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1534
1535         hlist_for_each_entry(pol, chain, bydst) {
1536                 if (pol->type == policy->type &&
1537                     pol->if_id == policy->if_id &&
1538                     !selector_cmp(&pol->selector, &policy->selector) &&
1539                     xfrm_policy_mark_match(policy, pol) &&
1540                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1541                     !WARN_ON(delpol)) {
1542                         if (excl)
1543                                 return ERR_PTR(-EEXIST);
1544                         delpol = pol;
1545                         if (policy->priority > pol->priority)
1546                                 continue;
1547                 } else if (policy->priority >= pol->priority) {
1548                         newpos = pol;
1549                         continue;
1550                 }
1551                 if (delpol)
1552                         break;
1553         }
1554
1555         if (newpos)
1556                 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1557         else
1558                 hlist_add_head_rcu(&policy->bydst, chain);
1559
1560         return delpol;
1561 }
1562
1563 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1564 {
1565         struct net *net = xp_net(policy);
1566         struct xfrm_policy *delpol;
1567         struct hlist_head *chain;
1568
1569         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1570         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1571         if (chain)
1572                 delpol = xfrm_policy_insert_list(chain, policy, excl);
1573         else
1574                 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1575
1576         if (IS_ERR(delpol)) {
1577                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1578                 return PTR_ERR(delpol);
1579         }
1580
1581         __xfrm_policy_link(policy, dir);
1582
1583         /* After previous checking, family can either be AF_INET or AF_INET6 */
1584         if (policy->family == AF_INET)
1585                 rt_genid_bump_ipv4(net);
1586         else
1587                 rt_genid_bump_ipv6(net);
1588
1589         if (delpol) {
1590                 xfrm_policy_requeue(delpol, policy);
1591                 __xfrm_policy_unlink(delpol, dir);
1592         }
1593         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1594         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1595         policy->curlft.add_time = ktime_get_real_seconds();
1596         policy->curlft.use_time = 0;
1597         if (!mod_timer(&policy->timer, jiffies + HZ))
1598                 xfrm_pol_hold(policy);
1599         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1600
1601         if (delpol)
1602                 xfrm_policy_kill(delpol);
1603         else if (xfrm_bydst_should_resize(net, dir, NULL))
1604                 schedule_work(&net->xfrm.policy_hash_work);
1605
1606         return 0;
1607 }
1608 EXPORT_SYMBOL(xfrm_policy_insert);
1609
1610 static struct xfrm_policy *
1611 __xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id,
1612                         u8 type, int dir,
1613                         struct xfrm_selector *sel,
1614                         struct xfrm_sec_ctx *ctx)
1615 {
1616         struct xfrm_policy *pol;
1617
1618         if (!chain)
1619                 return NULL;
1620
1621         hlist_for_each_entry(pol, chain, bydst) {
1622                 if (pol->type == type &&
1623                     pol->if_id == if_id &&
1624                     (mark & pol->mark.m) == pol->mark.v &&
1625                     !selector_cmp(sel, &pol->selector) &&
1626                     xfrm_sec_ctx_match(ctx, pol->security))
1627                         return pol;
1628         }
1629
1630         return NULL;
1631 }
1632
1633 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id,
1634                                           u8 type, int dir,
1635                                           struct xfrm_selector *sel,
1636                                           struct xfrm_sec_ctx *ctx, int delete,
1637                                           int *err)
1638 {
1639         struct xfrm_pol_inexact_bin *bin = NULL;
1640         struct xfrm_policy *pol, *ret = NULL;
1641         struct hlist_head *chain;
1642
1643         *err = 0;
1644         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1645         chain = policy_hash_bysel(net, sel, sel->family, dir);
1646         if (!chain) {
1647                 struct xfrm_pol_inexact_candidates cand;
1648                 int i;
1649
1650                 bin = xfrm_policy_inexact_lookup(net, type,
1651                                                  sel->family, dir, if_id);
1652                 if (!bin) {
1653                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1654                         return NULL;
1655                 }
1656
1657                 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1658                                                          &sel->saddr,
1659                                                          &sel->daddr)) {
1660                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1661                         return NULL;
1662                 }
1663
1664                 pol = NULL;
1665                 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1666                         struct xfrm_policy *tmp;
1667
1668                         tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1669                                                       if_id, type, dir,
1670                                                       sel, ctx);
1671                         if (!tmp)
1672                                 continue;
1673
1674                         if (!pol || tmp->pos < pol->pos)
1675                                 pol = tmp;
1676                 }
1677         } else {
1678                 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1679                                               sel, ctx);
1680         }
1681
1682         if (pol) {
1683                 xfrm_pol_hold(pol);
1684                 if (delete) {
1685                         *err = security_xfrm_policy_delete(pol->security);
1686                         if (*err) {
1687                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1688                                 return pol;
1689                         }
1690                         __xfrm_policy_unlink(pol, dir);
1691                 }
1692                 ret = pol;
1693         }
1694         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1695
1696         if (ret && delete)
1697                 xfrm_policy_kill(ret);
1698         if (bin && delete)
1699                 xfrm_policy_inexact_prune_bin(bin);
1700         return ret;
1701 }
1702 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1703
1704 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id,
1705                                      u8 type, int dir, u32 id, int delete,
1706                                      int *err)
1707 {
1708         struct xfrm_policy *pol, *ret;
1709         struct hlist_head *chain;
1710
1711         *err = -ENOENT;
1712         if (xfrm_policy_id2dir(id) != dir)
1713                 return NULL;
1714
1715         *err = 0;
1716         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1717         chain = net->xfrm.policy_byidx + idx_hash(net, id);
1718         ret = NULL;
1719         hlist_for_each_entry(pol, chain, byidx) {
1720                 if (pol->type == type && pol->index == id &&
1721                     pol->if_id == if_id &&
1722                     (mark & pol->mark.m) == pol->mark.v) {
1723                         xfrm_pol_hold(pol);
1724                         if (delete) {
1725                                 *err = security_xfrm_policy_delete(
1726                                                                 pol->security);
1727                                 if (*err) {
1728                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1729                                         return pol;
1730                                 }
1731                                 __xfrm_policy_unlink(pol, dir);
1732                         }
1733                         ret = pol;
1734                         break;
1735                 }
1736         }
1737         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1738
1739         if (ret && delete)
1740                 xfrm_policy_kill(ret);
1741         return ret;
1742 }
1743 EXPORT_SYMBOL(xfrm_policy_byid);
1744
1745 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1746 static inline int
1747 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1748 {
1749         struct xfrm_policy *pol;
1750         int err = 0;
1751
1752         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1753                 if (pol->walk.dead ||
1754                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1755                     pol->type != type)
1756                         continue;
1757
1758                 err = security_xfrm_policy_delete(pol->security);
1759                 if (err) {
1760                         xfrm_audit_policy_delete(pol, 0, task_valid);
1761                         return err;
1762                 }
1763         }
1764         return err;
1765 }
1766 #else
1767 static inline int
1768 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1769 {
1770         return 0;
1771 }
1772 #endif
1773
1774 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1775 {
1776         int dir, err = 0, cnt = 0;
1777         struct xfrm_policy *pol;
1778
1779         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1780
1781         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1782         if (err)
1783                 goto out;
1784
1785 again:
1786         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1787                 dir = xfrm_policy_id2dir(pol->index);
1788                 if (pol->walk.dead ||
1789                     dir >= XFRM_POLICY_MAX ||
1790                     pol->type != type)
1791                         continue;
1792
1793                 __xfrm_policy_unlink(pol, dir);
1794                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1795                 cnt++;
1796                 xfrm_audit_policy_delete(pol, 1, task_valid);
1797                 xfrm_policy_kill(pol);
1798                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1799                 goto again;
1800         }
1801         if (cnt)
1802                 __xfrm_policy_inexact_flush(net);
1803         else
1804                 err = -ESRCH;
1805 out:
1806         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1807         return err;
1808 }
1809 EXPORT_SYMBOL(xfrm_policy_flush);
1810
1811 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1812                      int (*func)(struct xfrm_policy *, int, int, void*),
1813                      void *data)
1814 {
1815         struct xfrm_policy *pol;
1816         struct xfrm_policy_walk_entry *x;
1817         int error = 0;
1818
1819         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1820             walk->type != XFRM_POLICY_TYPE_ANY)
1821                 return -EINVAL;
1822
1823         if (list_empty(&walk->walk.all) && walk->seq != 0)
1824                 return 0;
1825
1826         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1827         if (list_empty(&walk->walk.all))
1828                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1829         else
1830                 x = list_first_entry(&walk->walk.all,
1831                                      struct xfrm_policy_walk_entry, all);
1832
1833         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1834                 if (x->dead)
1835                         continue;
1836                 pol = container_of(x, struct xfrm_policy, walk);
1837                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1838                     walk->type != pol->type)
1839                         continue;
1840                 error = func(pol, xfrm_policy_id2dir(pol->index),
1841                              walk->seq, data);
1842                 if (error) {
1843                         list_move_tail(&walk->walk.all, &x->all);
1844                         goto out;
1845                 }
1846                 walk->seq++;
1847         }
1848         if (walk->seq == 0) {
1849                 error = -ENOENT;
1850                 goto out;
1851         }
1852         list_del_init(&walk->walk.all);
1853 out:
1854         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1855         return error;
1856 }
1857 EXPORT_SYMBOL(xfrm_policy_walk);
1858
1859 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1860 {
1861         INIT_LIST_HEAD(&walk->walk.all);
1862         walk->walk.dead = 1;
1863         walk->type = type;
1864         walk->seq = 0;
1865 }
1866 EXPORT_SYMBOL(xfrm_policy_walk_init);
1867
1868 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1869 {
1870         if (list_empty(&walk->walk.all))
1871                 return;
1872
1873         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1874         list_del(&walk->walk.all);
1875         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1876 }
1877 EXPORT_SYMBOL(xfrm_policy_walk_done);
1878
1879 /*
1880  * Find policy to apply to this flow.
1881  *
1882  * Returns 0 if policy found, else an -errno.
1883  */
1884 static int xfrm_policy_match(const struct xfrm_policy *pol,
1885                              const struct flowi *fl,
1886                              u8 type, u16 family, int dir, u32 if_id)
1887 {
1888         const struct xfrm_selector *sel = &pol->selector;
1889         int ret = -ESRCH;
1890         bool match;
1891
1892         if (pol->family != family ||
1893             pol->if_id != if_id ||
1894             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1895             pol->type != type)
1896                 return ret;
1897
1898         match = xfrm_selector_match(sel, fl, family);
1899         if (match)
1900                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1901                                                   dir);
1902         return ret;
1903 }
1904
1905 static struct xfrm_pol_inexact_node *
1906 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1907                                 seqcount_t *count,
1908                                 const xfrm_address_t *addr, u16 family)
1909 {
1910         const struct rb_node *parent;
1911         int seq;
1912
1913 again:
1914         seq = read_seqcount_begin(count);
1915
1916         parent = rcu_dereference_raw(r->rb_node);
1917         while (parent) {
1918                 struct xfrm_pol_inexact_node *node;
1919                 int delta;
1920
1921                 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
1922
1923                 delta = xfrm_policy_addr_delta(addr, &node->addr,
1924                                                node->prefixlen, family);
1925                 if (delta < 0) {
1926                         parent = rcu_dereference_raw(parent->rb_left);
1927                         continue;
1928                 } else if (delta > 0) {
1929                         parent = rcu_dereference_raw(parent->rb_right);
1930                         continue;
1931                 }
1932
1933                 return node;
1934         }
1935
1936         if (read_seqcount_retry(count, seq))
1937                 goto again;
1938
1939         return NULL;
1940 }
1941
1942 static bool
1943 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
1944                                     struct xfrm_pol_inexact_bin *b,
1945                                     const xfrm_address_t *saddr,
1946                                     const xfrm_address_t *daddr)
1947 {
1948         struct xfrm_pol_inexact_node *n;
1949         u16 family;
1950
1951         if (!b)
1952                 return false;
1953
1954         family = b->k.family;
1955         memset(cand, 0, sizeof(*cand));
1956         cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
1957
1958         n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
1959                                             family);
1960         if (n) {
1961                 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
1962                 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
1963                                                     family);
1964                 if (n)
1965                         cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
1966         }
1967
1968         n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
1969                                             family);
1970         if (n)
1971                 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
1972
1973         return true;
1974 }
1975
1976 static struct xfrm_pol_inexact_bin *
1977 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
1978                                u8 dir, u32 if_id)
1979 {
1980         struct xfrm_pol_inexact_key k = {
1981                 .family = family,
1982                 .type = type,
1983                 .dir = dir,
1984                 .if_id = if_id,
1985         };
1986
1987         write_pnet(&k.net, net);
1988
1989         return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
1990                                  xfrm_pol_inexact_params);
1991 }
1992
1993 static struct xfrm_pol_inexact_bin *
1994 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
1995                            u8 dir, u32 if_id)
1996 {
1997         struct xfrm_pol_inexact_bin *bin;
1998
1999         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2000
2001         rcu_read_lock();
2002         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2003         rcu_read_unlock();
2004
2005         return bin;
2006 }
2007
2008 static struct xfrm_policy *
2009 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2010                               struct xfrm_policy *prefer,
2011                               const struct flowi *fl,
2012                               u8 type, u16 family, int dir, u32 if_id)
2013 {
2014         u32 priority = prefer ? prefer->priority : ~0u;
2015         struct xfrm_policy *pol;
2016
2017         if (!chain)
2018                 return NULL;
2019
2020         hlist_for_each_entry_rcu(pol, chain, bydst) {
2021                 int err;
2022
2023                 if (pol->priority > priority)
2024                         break;
2025
2026                 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2027                 if (err) {
2028                         if (err != -ESRCH)
2029                                 return ERR_PTR(err);
2030
2031                         continue;
2032                 }
2033
2034                 if (prefer) {
2035                         /* matches.  Is it older than *prefer? */
2036                         if (pol->priority == priority &&
2037                             prefer->pos < pol->pos)
2038                                 return prefer;
2039                 }
2040
2041                 return pol;
2042         }
2043
2044         return NULL;
2045 }
2046
2047 static struct xfrm_policy *
2048 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2049                             struct xfrm_policy *prefer,
2050                             const struct flowi *fl,
2051                             u8 type, u16 family, int dir, u32 if_id)
2052 {
2053         struct xfrm_policy *tmp;
2054         int i;
2055
2056         for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2057                 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2058                                                     prefer,
2059                                                     fl, type, family, dir,
2060                                                     if_id);
2061                 if (!tmp)
2062                         continue;
2063
2064                 if (IS_ERR(tmp))
2065                         return tmp;
2066                 prefer = tmp;
2067         }
2068
2069         return prefer;
2070 }
2071
2072 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2073                                                      const struct flowi *fl,
2074                                                      u16 family, u8 dir,
2075                                                      u32 if_id)
2076 {
2077         struct xfrm_pol_inexact_candidates cand;
2078         const xfrm_address_t *daddr, *saddr;
2079         struct xfrm_pol_inexact_bin *bin;
2080         struct xfrm_policy *pol, *ret;
2081         struct hlist_head *chain;
2082         unsigned int sequence;
2083         int err;
2084
2085         daddr = xfrm_flowi_daddr(fl, family);
2086         saddr = xfrm_flowi_saddr(fl, family);
2087         if (unlikely(!daddr || !saddr))
2088                 return NULL;
2089
2090         rcu_read_lock();
2091  retry:
2092         do {
2093                 sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
2094                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2095         } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
2096
2097         ret = NULL;
2098         hlist_for_each_entry_rcu(pol, chain, bydst) {
2099                 err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2100                 if (err) {
2101                         if (err == -ESRCH)
2102                                 continue;
2103                         else {
2104                                 ret = ERR_PTR(err);
2105                                 goto fail;
2106                         }
2107                 } else {
2108                         ret = pol;
2109                         break;
2110                 }
2111         }
2112         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2113         if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2114                                                          daddr))
2115                 goto skip_inexact;
2116
2117         pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2118                                           family, dir, if_id);
2119         if (pol) {
2120                 ret = pol;
2121                 if (IS_ERR(pol))
2122                         goto fail;
2123         }
2124
2125 skip_inexact:
2126         if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
2127                 goto retry;
2128
2129         if (ret && !xfrm_pol_hold_rcu(ret))
2130                 goto retry;
2131 fail:
2132         rcu_read_unlock();
2133
2134         return ret;
2135 }
2136
2137 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2138                                               const struct flowi *fl,
2139                                               u16 family, u8 dir, u32 if_id)
2140 {
2141 #ifdef CONFIG_XFRM_SUB_POLICY
2142         struct xfrm_policy *pol;
2143
2144         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2145                                         dir, if_id);
2146         if (pol != NULL)
2147                 return pol;
2148 #endif
2149         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2150                                          dir, if_id);
2151 }
2152
2153 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2154                                                  const struct flowi *fl,
2155                                                  u16 family, u32 if_id)
2156 {
2157         struct xfrm_policy *pol;
2158
2159         rcu_read_lock();
2160  again:
2161         pol = rcu_dereference(sk->sk_policy[dir]);
2162         if (pol != NULL) {
2163                 bool match;
2164                 int err = 0;
2165
2166                 if (pol->family != family) {
2167                         pol = NULL;
2168                         goto out;
2169                 }
2170
2171                 match = xfrm_selector_match(&pol->selector, fl, family);
2172                 if (match) {
2173                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
2174                             pol->if_id != if_id) {
2175                                 pol = NULL;
2176                                 goto out;
2177                         }
2178                         err = security_xfrm_policy_lookup(pol->security,
2179                                                       fl->flowi_secid,
2180                                                       dir);
2181                         if (!err) {
2182                                 if (!xfrm_pol_hold_rcu(pol))
2183                                         goto again;
2184                         } else if (err == -ESRCH) {
2185                                 pol = NULL;
2186                         } else {
2187                                 pol = ERR_PTR(err);
2188                         }
2189                 } else
2190                         pol = NULL;
2191         }
2192 out:
2193         rcu_read_unlock();
2194         return pol;
2195 }
2196
2197 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2198 {
2199         struct net *net = xp_net(pol);
2200
2201         list_add(&pol->walk.all, &net->xfrm.policy_all);
2202         net->xfrm.policy_count[dir]++;
2203         xfrm_pol_hold(pol);
2204 }
2205
2206 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2207                                                 int dir)
2208 {
2209         struct net *net = xp_net(pol);
2210
2211         if (list_empty(&pol->walk.all))
2212                 return NULL;
2213
2214         /* Socket policies are not hashed. */
2215         if (!hlist_unhashed(&pol->bydst)) {
2216                 hlist_del_rcu(&pol->bydst);
2217                 hlist_del_init(&pol->bydst_inexact_list);
2218                 hlist_del(&pol->byidx);
2219         }
2220
2221         list_del_init(&pol->walk.all);
2222         net->xfrm.policy_count[dir]--;
2223
2224         return pol;
2225 }
2226
2227 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2228 {
2229         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2230 }
2231
2232 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2233 {
2234         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2235 }
2236
2237 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2238 {
2239         struct net *net = xp_net(pol);
2240
2241         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2242         pol = __xfrm_policy_unlink(pol, dir);
2243         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2244         if (pol) {
2245                 xfrm_policy_kill(pol);
2246                 return 0;
2247         }
2248         return -ENOENT;
2249 }
2250 EXPORT_SYMBOL(xfrm_policy_delete);
2251
2252 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2253 {
2254         struct net *net = sock_net(sk);
2255         struct xfrm_policy *old_pol;
2256
2257 #ifdef CONFIG_XFRM_SUB_POLICY
2258         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2259                 return -EINVAL;
2260 #endif
2261
2262         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2263         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2264                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2265         if (pol) {
2266                 pol->curlft.add_time = ktime_get_real_seconds();
2267                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2268                 xfrm_sk_policy_link(pol, dir);
2269         }
2270         rcu_assign_pointer(sk->sk_policy[dir], pol);
2271         if (old_pol) {
2272                 if (pol)
2273                         xfrm_policy_requeue(old_pol, pol);
2274
2275                 /* Unlinking succeeds always. This is the only function
2276                  * allowed to delete or replace socket policy.
2277                  */
2278                 xfrm_sk_policy_unlink(old_pol, dir);
2279         }
2280         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2281
2282         if (old_pol) {
2283                 xfrm_policy_kill(old_pol);
2284         }
2285         return 0;
2286 }
2287
2288 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2289 {
2290         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2291         struct net *net = xp_net(old);
2292
2293         if (newp) {
2294                 newp->selector = old->selector;
2295                 if (security_xfrm_policy_clone(old->security,
2296                                                &newp->security)) {
2297                         kfree(newp);
2298                         return NULL;  /* ENOMEM */
2299                 }
2300                 newp->lft = old->lft;
2301                 newp->curlft = old->curlft;
2302                 newp->mark = old->mark;
2303                 newp->if_id = old->if_id;
2304                 newp->action = old->action;
2305                 newp->flags = old->flags;
2306                 newp->xfrm_nr = old->xfrm_nr;
2307                 newp->index = old->index;
2308                 newp->type = old->type;
2309                 newp->family = old->family;
2310                 memcpy(newp->xfrm_vec, old->xfrm_vec,
2311                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2312                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2313                 xfrm_sk_policy_link(newp, dir);
2314                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2315                 xfrm_pol_put(newp);
2316         }
2317         return newp;
2318 }
2319
2320 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2321 {
2322         const struct xfrm_policy *p;
2323         struct xfrm_policy *np;
2324         int i, ret = 0;
2325
2326         rcu_read_lock();
2327         for (i = 0; i < 2; i++) {
2328                 p = rcu_dereference(osk->sk_policy[i]);
2329                 if (p) {
2330                         np = clone_policy(p, i);
2331                         if (unlikely(!np)) {
2332                                 ret = -ENOMEM;
2333                                 break;
2334                         }
2335                         rcu_assign_pointer(sk->sk_policy[i], np);
2336                 }
2337         }
2338         rcu_read_unlock();
2339         return ret;
2340 }
2341
2342 static int
2343 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2344                xfrm_address_t *remote, unsigned short family, u32 mark)
2345 {
2346         int err;
2347         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2348
2349         if (unlikely(afinfo == NULL))
2350                 return -EINVAL;
2351         err = afinfo->get_saddr(net, oif, local, remote, mark);
2352         rcu_read_unlock();
2353         return err;
2354 }
2355
2356 /* Resolve list of templates for the flow, given policy. */
2357
2358 static int
2359 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2360                       struct xfrm_state **xfrm, unsigned short family)
2361 {
2362         struct net *net = xp_net(policy);
2363         int nx;
2364         int i, error;
2365         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2366         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2367         xfrm_address_t tmp;
2368
2369         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2370                 struct xfrm_state *x;
2371                 xfrm_address_t *remote = daddr;
2372                 xfrm_address_t *local  = saddr;
2373                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2374
2375                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2376                     tmpl->mode == XFRM_MODE_BEET) {
2377                         remote = &tmpl->id.daddr;
2378                         local = &tmpl->saddr;
2379                         if (xfrm_addr_any(local, tmpl->encap_family)) {
2380                                 error = xfrm_get_saddr(net, fl->flowi_oif,
2381                                                        &tmp, remote,
2382                                                        tmpl->encap_family, 0);
2383                                 if (error)
2384                                         goto fail;
2385                                 local = &tmp;
2386                         }
2387                 }
2388
2389                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2390                                     family, policy->if_id);
2391
2392                 if (x && x->km.state == XFRM_STATE_VALID) {
2393                         xfrm[nx++] = x;
2394                         daddr = remote;
2395                         saddr = local;
2396                         continue;
2397                 }
2398                 if (x) {
2399                         error = (x->km.state == XFRM_STATE_ERROR ?
2400                                  -EINVAL : -EAGAIN);
2401                         xfrm_state_put(x);
2402                 } else if (error == -ESRCH) {
2403                         error = -EAGAIN;
2404                 }
2405
2406                 if (!tmpl->optional)
2407                         goto fail;
2408         }
2409         return nx;
2410
2411 fail:
2412         for (nx--; nx >= 0; nx--)
2413                 xfrm_state_put(xfrm[nx]);
2414         return error;
2415 }
2416
2417 static int
2418 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2419                   struct xfrm_state **xfrm, unsigned short family)
2420 {
2421         struct xfrm_state *tp[XFRM_MAX_DEPTH];
2422         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2423         int cnx = 0;
2424         int error;
2425         int ret;
2426         int i;
2427
2428         for (i = 0; i < npols; i++) {
2429                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2430                         error = -ENOBUFS;
2431                         goto fail;
2432                 }
2433
2434                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2435                 if (ret < 0) {
2436                         error = ret;
2437                         goto fail;
2438                 } else
2439                         cnx += ret;
2440         }
2441
2442         /* found states are sorted for outbound processing */
2443         if (npols > 1)
2444                 xfrm_state_sort(xfrm, tpp, cnx, family);
2445
2446         return cnx;
2447
2448  fail:
2449         for (cnx--; cnx >= 0; cnx--)
2450                 xfrm_state_put(tpp[cnx]);
2451         return error;
2452
2453 }
2454
2455 static int xfrm_get_tos(const struct flowi *fl, int family)
2456 {
2457         if (family == AF_INET)
2458                 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2459
2460         return 0;
2461 }
2462
2463 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2464 {
2465         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2466         struct dst_ops *dst_ops;
2467         struct xfrm_dst *xdst;
2468
2469         if (!afinfo)
2470                 return ERR_PTR(-EINVAL);
2471
2472         switch (family) {
2473         case AF_INET:
2474                 dst_ops = &net->xfrm.xfrm4_dst_ops;
2475                 break;
2476 #if IS_ENABLED(CONFIG_IPV6)
2477         case AF_INET6:
2478                 dst_ops = &net->xfrm.xfrm6_dst_ops;
2479                 break;
2480 #endif
2481         default:
2482                 BUG();
2483         }
2484         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2485
2486         if (likely(xdst)) {
2487                 struct dst_entry *dst = &xdst->u.dst;
2488
2489                 memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
2490         } else
2491                 xdst = ERR_PTR(-ENOBUFS);
2492
2493         rcu_read_unlock();
2494
2495         return xdst;
2496 }
2497
2498 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2499                            int nfheader_len)
2500 {
2501         if (dst->ops->family == AF_INET6) {
2502                 struct rt6_info *rt = (struct rt6_info *)dst;
2503                 path->path_cookie = rt6_get_cookie(rt);
2504                 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2505         }
2506 }
2507
2508 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2509                                 const struct flowi *fl)
2510 {
2511         const struct xfrm_policy_afinfo *afinfo =
2512                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2513         int err;
2514
2515         if (!afinfo)
2516                 return -EINVAL;
2517
2518         err = afinfo->fill_dst(xdst, dev, fl);
2519
2520         rcu_read_unlock();
2521
2522         return err;
2523 }
2524
2525
2526 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2527  * all the metrics... Shortly, bundle a bundle.
2528  */
2529
2530 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2531                                             struct xfrm_state **xfrm,
2532                                             struct xfrm_dst **bundle,
2533                                             int nx,
2534                                             const struct flowi *fl,
2535                                             struct dst_entry *dst)
2536 {
2537         const struct xfrm_state_afinfo *afinfo;
2538         const struct xfrm_mode *inner_mode;
2539         struct net *net = xp_net(policy);
2540         unsigned long now = jiffies;
2541         struct net_device *dev;
2542         struct xfrm_dst *xdst_prev = NULL;
2543         struct xfrm_dst *xdst0 = NULL;
2544         int i = 0;
2545         int err;
2546         int header_len = 0;
2547         int nfheader_len = 0;
2548         int trailer_len = 0;
2549         int tos;
2550         int family = policy->selector.family;
2551         xfrm_address_t saddr, daddr;
2552
2553         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2554
2555         tos = xfrm_get_tos(fl, family);
2556
2557         dst_hold(dst);
2558
2559         for (; i < nx; i++) {
2560                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2561                 struct dst_entry *dst1 = &xdst->u.dst;
2562
2563                 err = PTR_ERR(xdst);
2564                 if (IS_ERR(xdst)) {
2565                         dst_release(dst);
2566                         goto put_states;
2567                 }
2568
2569                 bundle[i] = xdst;
2570                 if (!xdst_prev)
2571                         xdst0 = xdst;
2572                 else
2573                         /* Ref count is taken during xfrm_alloc_dst()
2574                          * No need to do dst_clone() on dst1
2575                          */
2576                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2577
2578                 if (xfrm[i]->sel.family == AF_UNSPEC) {
2579                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
2580                                                         xfrm_af2proto(family));
2581                         if (!inner_mode) {
2582                                 err = -EAFNOSUPPORT;
2583                                 dst_release(dst);
2584                                 goto put_states;
2585                         }
2586                 } else
2587                         inner_mode = &xfrm[i]->inner_mode;
2588
2589                 xdst->route = dst;
2590                 dst_copy_metrics(dst1, dst);
2591
2592                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2593                         __u32 mark = 0;
2594
2595                         if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2596                                 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2597
2598                         family = xfrm[i]->props.family;
2599                         dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
2600                                               &saddr, &daddr, family, mark);
2601                         err = PTR_ERR(dst);
2602                         if (IS_ERR(dst))
2603                                 goto put_states;
2604                 } else
2605                         dst_hold(dst);
2606
2607                 dst1->xfrm = xfrm[i];
2608                 xdst->xfrm_genid = xfrm[i]->genid;
2609
2610                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2611                 dst1->flags |= DST_HOST;
2612                 dst1->lastuse = now;
2613
2614                 dst1->input = dst_discard;
2615
2616                 rcu_read_lock();
2617                 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2618                 if (likely(afinfo))
2619                         dst1->output = afinfo->output;
2620                 else
2621                         dst1->output = dst_discard_out;
2622                 rcu_read_unlock();
2623
2624                 xdst_prev = xdst;
2625
2626                 header_len += xfrm[i]->props.header_len;
2627                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2628                         nfheader_len += xfrm[i]->props.header_len;
2629                 trailer_len += xfrm[i]->props.trailer_len;
2630         }
2631
2632         xfrm_dst_set_child(xdst_prev, dst);
2633         xdst0->path = dst;
2634
2635         err = -ENODEV;
2636         dev = dst->dev;
2637         if (!dev)
2638                 goto free_dst;
2639
2640         xfrm_init_path(xdst0, dst, nfheader_len);
2641         xfrm_init_pmtu(bundle, nx);
2642
2643         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2644              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2645                 err = xfrm_fill_dst(xdst_prev, dev, fl);
2646                 if (err)
2647                         goto free_dst;
2648
2649                 xdst_prev->u.dst.header_len = header_len;
2650                 xdst_prev->u.dst.trailer_len = trailer_len;
2651                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2652                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2653         }
2654
2655         return &xdst0->u.dst;
2656
2657 put_states:
2658         for (; i < nx; i++)
2659                 xfrm_state_put(xfrm[i]);
2660 free_dst:
2661         if (xdst0)
2662                 dst_release_immediate(&xdst0->u.dst);
2663
2664         return ERR_PTR(err);
2665 }
2666
2667 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2668                                 struct xfrm_policy **pols,
2669                                 int *num_pols, int *num_xfrms)
2670 {
2671         int i;
2672
2673         if (*num_pols == 0 || !pols[0]) {
2674                 *num_pols = 0;
2675                 *num_xfrms = 0;
2676                 return 0;
2677         }
2678         if (IS_ERR(pols[0]))
2679                 return PTR_ERR(pols[0]);
2680
2681         *num_xfrms = pols[0]->xfrm_nr;
2682
2683 #ifdef CONFIG_XFRM_SUB_POLICY
2684         if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
2685             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2686                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2687                                                     XFRM_POLICY_TYPE_MAIN,
2688                                                     fl, family,
2689                                                     XFRM_POLICY_OUT,
2690                                                     pols[0]->if_id);
2691                 if (pols[1]) {
2692                         if (IS_ERR(pols[1])) {
2693                                 xfrm_pols_put(pols, *num_pols);
2694                                 return PTR_ERR(pols[1]);
2695                         }
2696                         (*num_pols)++;
2697                         (*num_xfrms) += pols[1]->xfrm_nr;
2698                 }
2699         }
2700 #endif
2701         for (i = 0; i < *num_pols; i++) {
2702                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2703                         *num_xfrms = -1;
2704                         break;
2705                 }
2706         }
2707
2708         return 0;
2709
2710 }
2711
2712 static struct xfrm_dst *
2713 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2714                                const struct flowi *fl, u16 family,
2715                                struct dst_entry *dst_orig)
2716 {
2717         struct net *net = xp_net(pols[0]);
2718         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2719         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2720         struct xfrm_dst *xdst;
2721         struct dst_entry *dst;
2722         int err;
2723
2724         /* Try to instantiate a bundle */
2725         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2726         if (err <= 0) {
2727                 if (err == 0)
2728                         return NULL;
2729
2730                 if (err != -EAGAIN)
2731                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2732                 return ERR_PTR(err);
2733         }
2734
2735         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2736         if (IS_ERR(dst)) {
2737                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2738                 return ERR_CAST(dst);
2739         }
2740
2741         xdst = (struct xfrm_dst *)dst;
2742         xdst->num_xfrms = err;
2743         xdst->num_pols = num_pols;
2744         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2745         xdst->policy_genid = atomic_read(&pols[0]->genid);
2746
2747         return xdst;
2748 }
2749
2750 static void xfrm_policy_queue_process(struct timer_list *t)
2751 {
2752         struct sk_buff *skb;
2753         struct sock *sk;
2754         struct dst_entry *dst;
2755         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2756         struct net *net = xp_net(pol);
2757         struct xfrm_policy_queue *pq = &pol->polq;
2758         struct flowi fl;
2759         struct sk_buff_head list;
2760
2761         spin_lock(&pq->hold_queue.lock);
2762         skb = skb_peek(&pq->hold_queue);
2763         if (!skb) {
2764                 spin_unlock(&pq->hold_queue.lock);
2765                 goto out;
2766         }
2767         dst = skb_dst(skb);
2768         sk = skb->sk;
2769         xfrm_decode_session(skb, &fl, dst->ops->family);
2770         spin_unlock(&pq->hold_queue.lock);
2771
2772         dst_hold(xfrm_dst_path(dst));
2773         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2774         if (IS_ERR(dst))
2775                 goto purge_queue;
2776
2777         if (dst->flags & DST_XFRM_QUEUE) {
2778                 dst_release(dst);
2779
2780                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2781                         goto purge_queue;
2782
2783                 pq->timeout = pq->timeout << 1;
2784                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2785                         xfrm_pol_hold(pol);
2786                 goto out;
2787         }
2788
2789         dst_release(dst);
2790
2791         __skb_queue_head_init(&list);
2792
2793         spin_lock(&pq->hold_queue.lock);
2794         pq->timeout = 0;
2795         skb_queue_splice_init(&pq->hold_queue, &list);
2796         spin_unlock(&pq->hold_queue.lock);
2797
2798         while (!skb_queue_empty(&list)) {
2799                 skb = __skb_dequeue(&list);
2800
2801                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2802                 dst_hold(xfrm_dst_path(skb_dst(skb)));
2803                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2804                 if (IS_ERR(dst)) {
2805                         kfree_skb(skb);
2806                         continue;
2807                 }
2808
2809                 nf_reset(skb);
2810                 skb_dst_drop(skb);
2811                 skb_dst_set(skb, dst);
2812
2813                 dst_output(net, skb->sk, skb);
2814         }
2815
2816 out:
2817         xfrm_pol_put(pol);
2818         return;
2819
2820 purge_queue:
2821         pq->timeout = 0;
2822         skb_queue_purge(&pq->hold_queue);
2823         xfrm_pol_put(pol);
2824 }
2825
2826 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2827 {
2828         unsigned long sched_next;
2829         struct dst_entry *dst = skb_dst(skb);
2830         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2831         struct xfrm_policy *pol = xdst->pols[0];
2832         struct xfrm_policy_queue *pq = &pol->polq;
2833
2834         if (unlikely(skb_fclone_busy(sk, skb))) {
2835                 kfree_skb(skb);
2836                 return 0;
2837         }
2838
2839         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2840                 kfree_skb(skb);
2841                 return -EAGAIN;
2842         }
2843
2844         skb_dst_force(skb);
2845
2846         spin_lock_bh(&pq->hold_queue.lock);
2847
2848         if (!pq->timeout)
2849                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2850
2851         sched_next = jiffies + pq->timeout;
2852
2853         if (del_timer(&pq->hold_timer)) {
2854                 if (time_before(pq->hold_timer.expires, sched_next))
2855                         sched_next = pq->hold_timer.expires;
2856                 xfrm_pol_put(pol);
2857         }
2858
2859         __skb_queue_tail(&pq->hold_queue, skb);
2860         if (!mod_timer(&pq->hold_timer, sched_next))
2861                 xfrm_pol_hold(pol);
2862
2863         spin_unlock_bh(&pq->hold_queue.lock);
2864
2865         return 0;
2866 }
2867
2868 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2869                                                  struct xfrm_flo *xflo,
2870                                                  const struct flowi *fl,
2871                                                  int num_xfrms,
2872                                                  u16 family)
2873 {
2874         int err;
2875         struct net_device *dev;
2876         struct dst_entry *dst;
2877         struct dst_entry *dst1;
2878         struct xfrm_dst *xdst;
2879
2880         xdst = xfrm_alloc_dst(net, family);
2881         if (IS_ERR(xdst))
2882                 return xdst;
2883
2884         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2885             net->xfrm.sysctl_larval_drop ||
2886             num_xfrms <= 0)
2887                 return xdst;
2888
2889         dst = xflo->dst_orig;
2890         dst1 = &xdst->u.dst;
2891         dst_hold(dst);
2892         xdst->route = dst;
2893
2894         dst_copy_metrics(dst1, dst);
2895
2896         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2897         dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2898         dst1->lastuse = jiffies;
2899
2900         dst1->input = dst_discard;
2901         dst1->output = xdst_queue_output;
2902
2903         dst_hold(dst);
2904         xfrm_dst_set_child(xdst, dst);
2905         xdst->path = dst;
2906
2907         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2908
2909         err = -ENODEV;
2910         dev = dst->dev;
2911         if (!dev)
2912                 goto free_dst;
2913
2914         err = xfrm_fill_dst(xdst, dev, fl);
2915         if (err)
2916                 goto free_dst;
2917
2918 out:
2919         return xdst;
2920
2921 free_dst:
2922         dst_release(dst1);
2923         xdst = ERR_PTR(err);
2924         goto out;
2925 }
2926
2927 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
2928                                            const struct flowi *fl,
2929                                            u16 family, u8 dir,
2930                                            struct xfrm_flo *xflo, u32 if_id)
2931 {
2932         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2933         int num_pols = 0, num_xfrms = 0, err;
2934         struct xfrm_dst *xdst;
2935
2936         /* Resolve policies to use if we couldn't get them from
2937          * previous cache entry */
2938         num_pols = 1;
2939         pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
2940         err = xfrm_expand_policies(fl, family, pols,
2941                                            &num_pols, &num_xfrms);
2942         if (err < 0)
2943                 goto inc_error;
2944         if (num_pols == 0)
2945                 return NULL;
2946         if (num_xfrms <= 0)
2947                 goto make_dummy_bundle;
2948
2949         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2950                                               xflo->dst_orig);
2951         if (IS_ERR(xdst)) {
2952                 err = PTR_ERR(xdst);
2953                 if (err == -EREMOTE) {
2954                         xfrm_pols_put(pols, num_pols);
2955                         return NULL;
2956                 }
2957
2958                 if (err != -EAGAIN)
2959                         goto error;
2960                 goto make_dummy_bundle;
2961         } else if (xdst == NULL) {
2962                 num_xfrms = 0;
2963                 goto make_dummy_bundle;
2964         }
2965
2966         return xdst;
2967
2968 make_dummy_bundle:
2969         /* We found policies, but there's no bundles to instantiate:
2970          * either because the policy blocks, has no transformations or
2971          * we could not build template (no xfrm_states).*/
2972         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2973         if (IS_ERR(xdst)) {
2974                 xfrm_pols_put(pols, num_pols);
2975                 return ERR_CAST(xdst);
2976         }
2977         xdst->num_pols = num_pols;
2978         xdst->num_xfrms = num_xfrms;
2979         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2980
2981         return xdst;
2982
2983 inc_error:
2984         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2985 error:
2986         xfrm_pols_put(pols, num_pols);
2987         return ERR_PTR(err);
2988 }
2989
2990 static struct dst_entry *make_blackhole(struct net *net, u16 family,
2991                                         struct dst_entry *dst_orig)
2992 {
2993         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2994         struct dst_entry *ret;
2995
2996         if (!afinfo) {
2997                 dst_release(dst_orig);
2998                 return ERR_PTR(-EINVAL);
2999         } else {
3000                 ret = afinfo->blackhole_route(net, dst_orig);
3001         }
3002         rcu_read_unlock();
3003
3004         return ret;
3005 }
3006
3007 /* Finds/creates a bundle for given flow and if_id
3008  *
3009  * At the moment we eat a raw IP route. Mostly to speed up lookups
3010  * on interfaces with disabled IPsec.
3011  *
3012  * xfrm_lookup uses an if_id of 0 by default, and is provided for
3013  * compatibility
3014  */
3015 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3016                                         struct dst_entry *dst_orig,
3017                                         const struct flowi *fl,
3018                                         const struct sock *sk,
3019                                         int flags, u32 if_id)
3020 {
3021         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3022         struct xfrm_dst *xdst;
3023         struct dst_entry *dst, *route;
3024         u16 family = dst_orig->ops->family;
3025         u8 dir = XFRM_POLICY_OUT;
3026         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3027
3028         dst = NULL;
3029         xdst = NULL;
3030         route = NULL;
3031
3032         sk = sk_const_to_full_sk(sk);
3033         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3034                 num_pols = 1;
3035                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3036                                                 if_id);
3037                 err = xfrm_expand_policies(fl, family, pols,
3038                                            &num_pols, &num_xfrms);
3039                 if (err < 0)
3040                         goto dropdst;
3041
3042                 if (num_pols) {
3043                         if (num_xfrms <= 0) {
3044                                 drop_pols = num_pols;
3045                                 goto no_transform;
3046                         }
3047
3048                         xdst = xfrm_resolve_and_create_bundle(
3049                                         pols, num_pols, fl,
3050                                         family, dst_orig);
3051
3052                         if (IS_ERR(xdst)) {
3053                                 xfrm_pols_put(pols, num_pols);
3054                                 err = PTR_ERR(xdst);
3055                                 if (err == -EREMOTE)
3056                                         goto nopol;
3057
3058                                 goto dropdst;
3059                         } else if (xdst == NULL) {
3060                                 num_xfrms = 0;
3061                                 drop_pols = num_pols;
3062                                 goto no_transform;
3063                         }
3064
3065                         route = xdst->route;
3066                 }
3067         }
3068
3069         if (xdst == NULL) {
3070                 struct xfrm_flo xflo;
3071
3072                 xflo.dst_orig = dst_orig;
3073                 xflo.flags = flags;
3074
3075                 /* To accelerate a bit...  */
3076                 if ((dst_orig->flags & DST_NOXFRM) ||
3077                     !net->xfrm.policy_count[XFRM_POLICY_OUT])
3078                         goto nopol;
3079
3080                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3081                 if (xdst == NULL)
3082                         goto nopol;
3083                 if (IS_ERR(xdst)) {
3084                         err = PTR_ERR(xdst);
3085                         goto dropdst;
3086                 }
3087
3088                 num_pols = xdst->num_pols;
3089                 num_xfrms = xdst->num_xfrms;
3090                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3091                 route = xdst->route;
3092         }
3093
3094         dst = &xdst->u.dst;
3095         if (route == NULL && num_xfrms > 0) {
3096                 /* The only case when xfrm_bundle_lookup() returns a
3097                  * bundle with null route, is when the template could
3098                  * not be resolved. It means policies are there, but
3099                  * bundle could not be created, since we don't yet
3100                  * have the xfrm_state's. We need to wait for KM to
3101                  * negotiate new SA's or bail out with error.*/
3102                 if (net->xfrm.sysctl_larval_drop) {
3103                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3104                         err = -EREMOTE;
3105                         goto error;
3106                 }
3107
3108                 err = -EAGAIN;
3109
3110                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3111                 goto error;
3112         }
3113
3114 no_transform:
3115         if (num_pols == 0)
3116                 goto nopol;
3117
3118         if ((flags & XFRM_LOOKUP_ICMP) &&
3119             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3120                 err = -ENOENT;
3121                 goto error;
3122         }
3123
3124         for (i = 0; i < num_pols; i++)
3125                 pols[i]->curlft.use_time = ktime_get_real_seconds();
3126
3127         if (num_xfrms < 0) {
3128                 /* Prohibit the flow */
3129                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3130                 err = -EPERM;
3131                 goto error;
3132         } else if (num_xfrms > 0) {
3133                 /* Flow transformed */
3134                 dst_release(dst_orig);
3135         } else {
3136                 /* Flow passes untransformed */
3137                 dst_release(dst);
3138                 dst = dst_orig;
3139         }
3140 ok:
3141         xfrm_pols_put(pols, drop_pols);
3142         if (dst && dst->xfrm &&
3143             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3144                 dst->flags |= DST_XFRM_TUNNEL;
3145         return dst;
3146
3147 nopol:
3148         if (!(flags & XFRM_LOOKUP_ICMP)) {
3149                 dst = dst_orig;
3150                 goto ok;
3151         }
3152         err = -ENOENT;
3153 error:
3154         dst_release(dst);
3155 dropdst:
3156         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3157                 dst_release(dst_orig);
3158         xfrm_pols_put(pols, drop_pols);
3159         return ERR_PTR(err);
3160 }
3161 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3162
3163 /* Main function: finds/creates a bundle for given flow.
3164  *
3165  * At the moment we eat a raw IP route. Mostly to speed up lookups
3166  * on interfaces with disabled IPsec.
3167  */
3168 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3169                               const struct flowi *fl, const struct sock *sk,
3170                               int flags)
3171 {
3172         return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3173 }
3174 EXPORT_SYMBOL(xfrm_lookup);
3175
3176 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3177  * Otherwise we may send out blackholed packets.
3178  */
3179 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3180                                     const struct flowi *fl,
3181                                     const struct sock *sk, int flags)
3182 {
3183         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3184                                             flags | XFRM_LOOKUP_QUEUE |
3185                                             XFRM_LOOKUP_KEEP_DST_REF);
3186
3187         if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
3188                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3189
3190         if (IS_ERR(dst))
3191                 dst_release(dst_orig);
3192
3193         return dst;
3194 }
3195 EXPORT_SYMBOL(xfrm_lookup_route);
3196
3197 static inline int
3198 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3199 {
3200         struct sec_path *sp = skb_sec_path(skb);
3201         struct xfrm_state *x;
3202
3203         if (!sp || idx < 0 || idx >= sp->len)
3204                 return 0;
3205         x = sp->xvec[idx];
3206         if (!x->type->reject)
3207                 return 0;
3208         return x->type->reject(x, skb, fl);
3209 }
3210
3211 /* When skb is transformed back to its "native" form, we have to
3212  * check policy restrictions. At the moment we make this in maximally
3213  * stupid way. Shame on me. :-) Of course, connected sockets must
3214  * have policy cached at them.
3215  */
3216
3217 static inline int
3218 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3219               unsigned short family)
3220 {
3221         if (xfrm_state_kern(x))
3222                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3223         return  x->id.proto == tmpl->id.proto &&
3224                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3225                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3226                 x->props.mode == tmpl->mode &&
3227                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3228                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3229                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3230                   xfrm_state_addr_cmp(tmpl, x, family));
3231 }
3232
3233 /*
3234  * 0 or more than 0 is returned when validation is succeeded (either bypass
3235  * because of optional transport mode, or next index of the mathced secpath
3236  * state with the template.
3237  * -1 is returned when no matching template is found.
3238  * Otherwise "-2 - errored_index" is returned.
3239  */
3240 static inline int
3241 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3242                unsigned short family)
3243 {
3244         int idx = start;
3245
3246         if (tmpl->optional) {
3247                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3248                         return start;
3249         } else
3250                 start = -1;
3251         for (; idx < sp->len; idx++) {
3252                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
3253                         return ++idx;
3254                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3255                         if (start == -1)
3256                                 start = -2-idx;
3257                         break;
3258                 }
3259         }
3260         return start;
3261 }
3262
3263 static void
3264 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3265 {
3266         const struct iphdr *iph = ip_hdr(skb);
3267         int ihl = iph->ihl;
3268         u8 *xprth = skb_network_header(skb) + ihl * 4;
3269         struct flowi4 *fl4 = &fl->u.ip4;
3270         int oif = 0;
3271
3272         if (skb_dst(skb))
3273                 oif = skb_dst(skb)->dev->ifindex;
3274
3275         memset(fl4, 0, sizeof(struct flowi4));
3276         fl4->flowi4_mark = skb->mark;
3277         fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3278
3279         fl4->flowi4_proto = iph->protocol;
3280         fl4->daddr = reverse ? iph->saddr : iph->daddr;
3281         fl4->saddr = reverse ? iph->daddr : iph->saddr;
3282         fl4->flowi4_tos = iph->tos;
3283
3284         if (!ip_is_fragment(iph)) {
3285                 switch (iph->protocol) {
3286                 case IPPROTO_UDP:
3287                 case IPPROTO_UDPLITE:
3288                 case IPPROTO_TCP:
3289                 case IPPROTO_SCTP:
3290                 case IPPROTO_DCCP:
3291                         if (xprth + 4 < skb->data ||
3292                             pskb_may_pull(skb, xprth + 4 - skb->data)) {
3293                                 __be16 *ports;
3294
3295                                 xprth = skb_network_header(skb) + ihl * 4;
3296                                 ports = (__be16 *)xprth;
3297
3298                                 fl4->fl4_sport = ports[!!reverse];
3299                                 fl4->fl4_dport = ports[!reverse];
3300                         }
3301                         break;
3302                 case IPPROTO_ICMP:
3303                         if (xprth + 2 < skb->data ||
3304                             pskb_may_pull(skb, xprth + 2 - skb->data)) {
3305                                 u8 *icmp;
3306
3307                                 xprth = skb_network_header(skb) + ihl * 4;
3308                                 icmp = xprth;
3309
3310                                 fl4->fl4_icmp_type = icmp[0];
3311                                 fl4->fl4_icmp_code = icmp[1];
3312                         }
3313                         break;
3314                 case IPPROTO_ESP:
3315                         if (xprth + 4 < skb->data ||
3316                             pskb_may_pull(skb, xprth + 4 - skb->data)) {
3317                                 __be32 *ehdr;
3318
3319                                 xprth = skb_network_header(skb) + ihl * 4;
3320                                 ehdr = (__be32 *)xprth;
3321
3322                                 fl4->fl4_ipsec_spi = ehdr[0];
3323                         }
3324                         break;
3325                 case IPPROTO_AH:
3326                         if (xprth + 8 < skb->data ||
3327                             pskb_may_pull(skb, xprth + 8 - skb->data)) {
3328                                 __be32 *ah_hdr;
3329
3330                                 xprth = skb_network_header(skb) + ihl * 4;
3331                                 ah_hdr = (__be32 *)xprth;
3332
3333                                 fl4->fl4_ipsec_spi = ah_hdr[1];
3334                         }
3335                         break;
3336                 case IPPROTO_COMP:
3337                         if (xprth + 4 < skb->data ||
3338                             pskb_may_pull(skb, xprth + 4 - skb->data)) {
3339                                 __be16 *ipcomp_hdr;
3340
3341                                 xprth = skb_network_header(skb) + ihl * 4;
3342                                 ipcomp_hdr = (__be16 *)xprth;
3343
3344                                 fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
3345                         }
3346                         break;
3347                 case IPPROTO_GRE:
3348                         if (xprth + 12 < skb->data ||
3349                             pskb_may_pull(skb, xprth + 12 - skb->data)) {
3350                                 __be16 *greflags;
3351                                 __be32 *gre_hdr;
3352
3353                                 xprth = skb_network_header(skb) + ihl * 4;
3354                                 greflags = (__be16 *)xprth;
3355                                 gre_hdr = (__be32 *)xprth;
3356
3357                                 if (greflags[0] & GRE_KEY) {
3358                                         if (greflags[0] & GRE_CSUM)
3359                                                 gre_hdr++;
3360                                         fl4->fl4_gre_key = gre_hdr[1];
3361                                 }
3362                         }
3363                         break;
3364                 default:
3365                         fl4->fl4_ipsec_spi = 0;
3366                         break;
3367                 }
3368         }
3369 }
3370
3371 #if IS_ENABLED(CONFIG_IPV6)
3372 static void
3373 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3374 {
3375         struct flowi6 *fl6 = &fl->u.ip6;
3376         int onlyproto = 0;
3377         const struct ipv6hdr *hdr = ipv6_hdr(skb);
3378         u32 offset = sizeof(*hdr);
3379         struct ipv6_opt_hdr *exthdr;
3380         const unsigned char *nh = skb_network_header(skb);
3381         u16 nhoff = IP6CB(skb)->nhoff;
3382         int oif = 0;
3383         u8 nexthdr;
3384
3385         if (!nhoff)
3386                 nhoff = offsetof(struct ipv6hdr, nexthdr);
3387
3388         nexthdr = nh[nhoff];
3389
3390         if (skb_dst(skb))
3391                 oif = skb_dst(skb)->dev->ifindex;
3392
3393         memset(fl6, 0, sizeof(struct flowi6));
3394         fl6->flowi6_mark = skb->mark;
3395         fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3396
3397         fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3398         fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3399
3400         while (nh + offset + sizeof(*exthdr) < skb->data ||
3401                pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3402                 nh = skb_network_header(skb);
3403                 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3404
3405                 switch (nexthdr) {
3406                 case NEXTHDR_FRAGMENT:
3407                         onlyproto = 1;
3408                         /* fall through */
3409                 case NEXTHDR_ROUTING:
3410                 case NEXTHDR_HOP:
3411                 case NEXTHDR_DEST:
3412                         offset += ipv6_optlen(exthdr);
3413                         nexthdr = exthdr->nexthdr;
3414                         exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3415                         break;
3416                 case IPPROTO_UDP:
3417                 case IPPROTO_UDPLITE:
3418                 case IPPROTO_TCP:
3419                 case IPPROTO_SCTP:
3420                 case IPPROTO_DCCP:
3421                         if (!onlyproto && (nh + offset + 4 < skb->data ||
3422                              pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3423                                 __be16 *ports;
3424
3425                                 nh = skb_network_header(skb);
3426                                 ports = (__be16 *)(nh + offset);
3427                                 fl6->fl6_sport = ports[!!reverse];
3428                                 fl6->fl6_dport = ports[!reverse];
3429                         }
3430                         fl6->flowi6_proto = nexthdr;
3431                         return;
3432                 case IPPROTO_ICMPV6:
3433                         if (!onlyproto && (nh + offset + 2 < skb->data ||
3434                             pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3435                                 u8 *icmp;
3436
3437                                 nh = skb_network_header(skb);
3438                                 icmp = (u8 *)(nh + offset);
3439                                 fl6->fl6_icmp_type = icmp[0];
3440                                 fl6->fl6_icmp_code = icmp[1];
3441                         }
3442                         fl6->flowi6_proto = nexthdr;
3443                         return;
3444 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3445                 case IPPROTO_MH:
3446                         offset += ipv6_optlen(exthdr);
3447                         if (!onlyproto && (nh + offset + 3 < skb->data ||
3448                             pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3449                                 struct ip6_mh *mh;
3450
3451                                 nh = skb_network_header(skb);
3452                                 mh = (struct ip6_mh *)(nh + offset);
3453                                 fl6->fl6_mh_type = mh->ip6mh_type;
3454                         }
3455                         fl6->flowi6_proto = nexthdr;
3456                         return;
3457 #endif
3458                 /* XXX Why are there these headers? */
3459                 case IPPROTO_AH:
3460                 case IPPROTO_ESP:
3461                 case IPPROTO_COMP:
3462                 default:
3463                         fl6->fl6_ipsec_spi = 0;
3464                         fl6->flowi6_proto = nexthdr;
3465                         return;
3466                 }
3467         }
3468 }
3469 #endif
3470
3471 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3472                           unsigned int family, int reverse)
3473 {
3474         switch (family) {
3475         case AF_INET:
3476                 decode_session4(skb, fl, reverse);
3477                 break;
3478 #if IS_ENABLED(CONFIG_IPV6)
3479         case AF_INET6:
3480                 decode_session6(skb, fl, reverse);
3481                 break;
3482 #endif
3483         default:
3484                 return -EAFNOSUPPORT;
3485         }
3486
3487         return security_xfrm_decode_session(skb, &fl->flowi_secid);
3488 }
3489 EXPORT_SYMBOL(__xfrm_decode_session);
3490
3491 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3492 {
3493         for (; k < sp->len; k++) {
3494                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3495                         *idxp = k;
3496                         return 1;
3497                 }
3498         }
3499
3500         return 0;
3501 }
3502
3503 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3504                         unsigned short family)
3505 {
3506         struct net *net = dev_net(skb->dev);
3507         struct xfrm_policy *pol;
3508         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3509         int npols = 0;
3510         int xfrm_nr;
3511         int pi;
3512         int reverse;
3513         struct flowi fl;
3514         int xerr_idx = -1;
3515         const struct xfrm_if_cb *ifcb;
3516         struct sec_path *sp;
3517         struct xfrm_if *xi;
3518         u32 if_id = 0;
3519
3520         rcu_read_lock();
3521         ifcb = xfrm_if_get_cb();
3522
3523         if (ifcb) {
3524                 xi = ifcb->decode_session(skb, family);
3525                 if (xi) {
3526                         if_id = xi->p.if_id;
3527                         net = xi->net;
3528                 }
3529         }
3530         rcu_read_unlock();
3531
3532         reverse = dir & ~XFRM_POLICY_MASK;
3533         dir &= XFRM_POLICY_MASK;
3534
3535         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3536                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3537                 return 0;
3538         }
3539
3540         nf_nat_decode_session(skb, &fl, family);
3541
3542         /* First, check used SA against their selectors. */
3543         sp = skb_sec_path(skb);
3544         if (sp) {
3545                 int i;
3546
3547                 for (i = sp->len - 1; i >= 0; i--) {
3548                         struct xfrm_state *x = sp->xvec[i];
3549                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
3550                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3551                                 return 0;
3552                         }
3553                 }
3554         }
3555
3556         pol = NULL;
3557         sk = sk_to_full_sk(sk);
3558         if (sk && sk->sk_policy[dir]) {
3559                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3560                 if (IS_ERR(pol)) {
3561                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3562                         return 0;
3563                 }
3564         }
3565
3566         if (!pol)
3567                 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3568
3569         if (IS_ERR(pol)) {
3570                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3571                 return 0;
3572         }
3573
3574         if (!pol) {
3575                 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3576                         xfrm_secpath_reject(xerr_idx, skb, &fl);
3577                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3578                         return 0;
3579                 }
3580                 return 1;
3581         }
3582
3583         pol->curlft.use_time = ktime_get_real_seconds();
3584
3585         pols[0] = pol;
3586         npols++;
3587 #ifdef CONFIG_XFRM_SUB_POLICY
3588         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3589                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3590                                                     &fl, family,
3591                                                     XFRM_POLICY_IN, if_id);
3592                 if (pols[1]) {
3593                         if (IS_ERR(pols[1])) {
3594                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3595                                 return 0;
3596                         }
3597                         pols[1]->curlft.use_time = ktime_get_real_seconds();
3598                         npols++;
3599                 }
3600         }
3601 #endif
3602
3603         if (pol->action == XFRM_POLICY_ALLOW) {
3604                 static struct sec_path dummy;
3605                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3606                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3607                 struct xfrm_tmpl **tpp = tp;
3608                 int ti = 0;
3609                 int i, k;
3610
3611                 sp = skb_sec_path(skb);
3612                 if (!sp)
3613                         sp = &dummy;
3614
3615                 for (pi = 0; pi < npols; pi++) {
3616                         if (pols[pi] != pol &&
3617                             pols[pi]->action != XFRM_POLICY_ALLOW) {
3618                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3619                                 goto reject;
3620                         }
3621                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3622                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3623                                 goto reject_error;
3624                         }
3625                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
3626                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3627                 }
3628                 xfrm_nr = ti;
3629                 if (npols > 1) {
3630                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
3631                         tpp = stp;
3632                 }
3633
3634                 /* For each tunnel xfrm, find the first matching tmpl.
3635                  * For each tmpl before that, find corresponding xfrm.
3636                  * Order is _important_. Later we will implement
3637                  * some barriers, but at the moment barriers
3638                  * are implied between each two transformations.
3639                  */
3640                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3641                         k = xfrm_policy_ok(tpp[i], sp, k, family);
3642                         if (k < 0) {
3643                                 if (k < -1)
3644                                         /* "-2 - errored_index" returned */
3645                                         xerr_idx = -(2+k);
3646                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3647                                 goto reject;
3648                         }
3649                 }
3650
3651                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3652                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3653                         goto reject;
3654                 }
3655
3656                 xfrm_pols_put(pols, npols);
3657                 return 1;
3658         }
3659         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3660
3661 reject:
3662         xfrm_secpath_reject(xerr_idx, skb, &fl);
3663 reject_error:
3664         xfrm_pols_put(pols, npols);
3665         return 0;
3666 }
3667 EXPORT_SYMBOL(__xfrm_policy_check);
3668
3669 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3670 {
3671         struct net *net = dev_net(skb->dev);
3672         struct flowi fl;
3673         struct dst_entry *dst;
3674         int res = 1;
3675
3676         if (xfrm_decode_session(skb, &fl, family) < 0) {
3677                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3678                 return 0;
3679         }
3680
3681         skb_dst_force(skb);
3682         if (!skb_dst(skb)) {
3683                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3684                 return 0;
3685         }
3686
3687         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3688         if (IS_ERR(dst)) {
3689                 res = 0;
3690                 dst = NULL;
3691         }
3692         skb_dst_set(skb, dst);
3693         return res;
3694 }
3695 EXPORT_SYMBOL(__xfrm_route_forward);
3696
3697 /* Optimize later using cookies and generation ids. */
3698
3699 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3700 {
3701         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3702          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3703          * get validated by dst_ops->check on every use.  We do this
3704          * because when a normal route referenced by an XFRM dst is
3705          * obsoleted we do not go looking around for all parent
3706          * referencing XFRM dsts so that we can invalidate them.  It
3707          * is just too much work.  Instead we make the checks here on
3708          * every use.  For example:
3709          *
3710          *      XFRM dst A --> IPv4 dst X
3711          *
3712          * X is the "xdst->route" of A (X is also the "dst->path" of A
3713          * in this example).  If X is marked obsolete, "A" will not
3714          * notice.  That's what we are validating here via the
3715          * stale_bundle() check.
3716          *
3717          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3718          * be marked on it.
3719          * This will force stale_bundle() to fail on any xdst bundle with
3720          * this dst linked in it.
3721          */
3722         if (dst->obsolete < 0 && !stale_bundle(dst))
3723                 return dst;
3724
3725         return NULL;
3726 }
3727
3728 static int stale_bundle(struct dst_entry *dst)
3729 {
3730         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3731 }
3732
3733 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3734 {
3735         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3736                 dst->dev = dev_net(dev)->loopback_dev;
3737                 dev_hold(dst->dev);
3738                 dev_put(dev);
3739         }
3740 }
3741 EXPORT_SYMBOL(xfrm_dst_ifdown);
3742
3743 static void xfrm_link_failure(struct sk_buff *skb)
3744 {
3745         /* Impossible. Such dst must be popped before reaches point of failure. */
3746 }
3747
3748 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3749 {
3750         if (dst) {
3751                 if (dst->obsolete) {
3752                         dst_release(dst);
3753                         dst = NULL;
3754                 }
3755         }
3756         return dst;
3757 }
3758
3759 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3760 {
3761         while (nr--) {
3762                 struct xfrm_dst *xdst = bundle[nr];
3763                 u32 pmtu, route_mtu_cached;
3764                 struct dst_entry *dst;
3765
3766                 dst = &xdst->u.dst;
3767                 pmtu = dst_mtu(xfrm_dst_child(dst));
3768                 xdst->child_mtu_cached = pmtu;
3769
3770                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3771
3772                 route_mtu_cached = dst_mtu(xdst->route);
3773                 xdst->route_mtu_cached = route_mtu_cached;
3774
3775                 if (pmtu > route_mtu_cached)
3776                         pmtu = route_mtu_cached;
3777
3778                 dst_metric_set(dst, RTAX_MTU, pmtu);
3779         }
3780 }
3781
3782 /* Check that the bundle accepts the flow and its components are
3783  * still valid.
3784  */
3785
3786 static int xfrm_bundle_ok(struct xfrm_dst *first)
3787 {
3788         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3789         struct dst_entry *dst = &first->u.dst;
3790         struct xfrm_dst *xdst;
3791         int start_from, nr;
3792         u32 mtu;
3793
3794         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3795             (dst->dev && !netif_running(dst->dev)))
3796                 return 0;
3797
3798         if (dst->flags & DST_XFRM_QUEUE)
3799                 return 1;
3800
3801         start_from = nr = 0;
3802         do {
3803                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3804
3805                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3806                         return 0;
3807                 if (xdst->xfrm_genid != dst->xfrm->genid)
3808                         return 0;
3809                 if (xdst->num_pols > 0 &&
3810                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3811                         return 0;
3812
3813                 bundle[nr++] = xdst;
3814
3815                 mtu = dst_mtu(xfrm_dst_child(dst));
3816                 if (xdst->child_mtu_cached != mtu) {
3817                         start_from = nr;
3818                         xdst->child_mtu_cached = mtu;
3819                 }
3820
3821                 if (!dst_check(xdst->route, xdst->route_cookie))
3822                         return 0;
3823                 mtu = dst_mtu(xdst->route);
3824                 if (xdst->route_mtu_cached != mtu) {
3825                         start_from = nr;
3826                         xdst->route_mtu_cached = mtu;
3827                 }
3828
3829                 dst = xfrm_dst_child(dst);
3830         } while (dst->xfrm);
3831
3832         if (likely(!start_from))
3833                 return 1;
3834
3835         xdst = bundle[start_from - 1];
3836         mtu = xdst->child_mtu_cached;
3837         while (start_from--) {
3838                 dst = &xdst->u.dst;
3839
3840                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3841                 if (mtu > xdst->route_mtu_cached)
3842                         mtu = xdst->route_mtu_cached;
3843                 dst_metric_set(dst, RTAX_MTU, mtu);
3844                 if (!start_from)
3845                         break;
3846
3847                 xdst = bundle[start_from - 1];
3848                 xdst->child_mtu_cached = mtu;
3849         }
3850
3851         return 1;
3852 }
3853
3854 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3855 {
3856         return dst_metric_advmss(xfrm_dst_path(dst));
3857 }
3858
3859 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3860 {
3861         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3862
3863         return mtu ? : dst_mtu(xfrm_dst_path(dst));
3864 }
3865
3866 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3867                                         const void *daddr)
3868 {
3869         while (dst->xfrm) {
3870                 const struct xfrm_state *xfrm = dst->xfrm;
3871
3872                 dst = xfrm_dst_child(dst);
3873
3874                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3875                         continue;
3876                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3877                         daddr = xfrm->coaddr;
3878                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3879                         daddr = &xfrm->id.daddr;
3880         }
3881         return daddr;
3882 }
3883
3884 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3885                                            struct sk_buff *skb,
3886                                            const void *daddr)
3887 {
3888         const struct dst_entry *path = xfrm_dst_path(dst);
3889
3890         if (!skb)
3891                 daddr = xfrm_get_dst_nexthop(dst, daddr);
3892         return path->ops->neigh_lookup(path, skb, daddr);
3893 }
3894
3895 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3896 {
3897         const struct dst_entry *path = xfrm_dst_path(dst);
3898
3899         daddr = xfrm_get_dst_nexthop(dst, daddr);
3900         path->ops->confirm_neigh(path, daddr);
3901 }
3902
3903 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3904 {
3905         int err = 0;
3906
3907         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3908                 return -EAFNOSUPPORT;
3909
3910         spin_lock(&xfrm_policy_afinfo_lock);
3911         if (unlikely(xfrm_policy_afinfo[family] != NULL))
3912                 err = -EEXIST;
3913         else {
3914                 struct dst_ops *dst_ops = afinfo->dst_ops;
3915                 if (likely(dst_ops->kmem_cachep == NULL))
3916                         dst_ops->kmem_cachep = xfrm_dst_cache;
3917                 if (likely(dst_ops->check == NULL))
3918                         dst_ops->check = xfrm_dst_check;
3919                 if (likely(dst_ops->default_advmss == NULL))
3920                         dst_ops->default_advmss = xfrm_default_advmss;
3921                 if (likely(dst_ops->mtu == NULL))
3922                         dst_ops->mtu = xfrm_mtu;
3923                 if (likely(dst_ops->negative_advice == NULL))
3924                         dst_ops->negative_advice = xfrm_negative_advice;
3925                 if (likely(dst_ops->link_failure == NULL))
3926                         dst_ops->link_failure = xfrm_link_failure;
3927                 if (likely(dst_ops->neigh_lookup == NULL))
3928                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
3929                 if (likely(!dst_ops->confirm_neigh))
3930                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
3931                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
3932         }
3933         spin_unlock(&xfrm_policy_afinfo_lock);
3934
3935         return err;
3936 }
3937 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
3938
3939 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
3940 {
3941         struct dst_ops *dst_ops = afinfo->dst_ops;
3942         int i;
3943
3944         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
3945                 if (xfrm_policy_afinfo[i] != afinfo)
3946                         continue;
3947                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
3948                 break;
3949         }
3950
3951         synchronize_rcu();
3952
3953         dst_ops->kmem_cachep = NULL;
3954         dst_ops->check = NULL;
3955         dst_ops->negative_advice = NULL;
3956         dst_ops->link_failure = NULL;
3957 }
3958 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
3959
3960 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
3961 {
3962         spin_lock(&xfrm_if_cb_lock);
3963         rcu_assign_pointer(xfrm_if_cb, ifcb);
3964         spin_unlock(&xfrm_if_cb_lock);
3965 }
3966 EXPORT_SYMBOL(xfrm_if_register_cb);
3967
3968 void xfrm_if_unregister_cb(void)
3969 {
3970         RCU_INIT_POINTER(xfrm_if_cb, NULL);
3971         synchronize_rcu();
3972 }
3973 EXPORT_SYMBOL(xfrm_if_unregister_cb);
3974
3975 #ifdef CONFIG_XFRM_STATISTICS
3976 static int __net_init xfrm_statistics_init(struct net *net)
3977 {
3978         int rv;
3979         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
3980         if (!net->mib.xfrm_statistics)
3981                 return -ENOMEM;
3982         rv = xfrm_proc_init(net);
3983         if (rv < 0)
3984                 free_percpu(net->mib.xfrm_statistics);
3985         return rv;
3986 }
3987
3988 static void xfrm_statistics_fini(struct net *net)
3989 {
3990         xfrm_proc_fini(net);
3991         free_percpu(net->mib.xfrm_statistics);
3992 }
3993 #else
3994 static int __net_init xfrm_statistics_init(struct net *net)
3995 {
3996         return 0;
3997 }
3998
3999 static void xfrm_statistics_fini(struct net *net)
4000 {
4001 }
4002 #endif
4003
4004 static int __net_init xfrm_policy_init(struct net *net)
4005 {
4006         unsigned int hmask, sz;
4007         int dir, err;
4008
4009         if (net_eq(net, &init_net)) {
4010                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4011                                            sizeof(struct xfrm_dst),
4012                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4013                                            NULL);
4014                 err = rhashtable_init(&xfrm_policy_inexact_table,
4015                                       &xfrm_pol_inexact_params);
4016                 BUG_ON(err);
4017         }
4018
4019         hmask = 8 - 1;
4020         sz = (hmask+1) * sizeof(struct hlist_head);
4021
4022         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4023         if (!net->xfrm.policy_byidx)
4024                 goto out_byidx;
4025         net->xfrm.policy_idx_hmask = hmask;
4026
4027         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4028                 struct xfrm_policy_hash *htab;
4029
4030                 net->xfrm.policy_count[dir] = 0;
4031                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4032                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4033
4034                 htab = &net->xfrm.policy_bydst[dir];
4035                 htab->table = xfrm_hash_alloc(sz);
4036                 if (!htab->table)
4037                         goto out_bydst;
4038                 htab->hmask = hmask;
4039                 htab->dbits4 = 32;
4040                 htab->sbits4 = 32;
4041                 htab->dbits6 = 128;
4042                 htab->sbits6 = 128;
4043         }
4044         net->xfrm.policy_hthresh.lbits4 = 32;
4045         net->xfrm.policy_hthresh.rbits4 = 32;
4046         net->xfrm.policy_hthresh.lbits6 = 128;
4047         net->xfrm.policy_hthresh.rbits6 = 128;
4048
4049         seqlock_init(&net->xfrm.policy_hthresh.lock);
4050
4051         INIT_LIST_HEAD(&net->xfrm.policy_all);
4052         INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4053         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4054         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4055         return 0;
4056
4057 out_bydst:
4058         for (dir--; dir >= 0; dir--) {
4059                 struct xfrm_policy_hash *htab;
4060
4061                 htab = &net->xfrm.policy_bydst[dir];
4062                 xfrm_hash_free(htab->table, sz);
4063         }
4064         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4065 out_byidx:
4066         return -ENOMEM;
4067 }
4068
4069 static void xfrm_policy_fini(struct net *net)
4070 {
4071         struct xfrm_pol_inexact_bin *b, *t;
4072         unsigned int sz;
4073         int dir;
4074
4075         flush_work(&net->xfrm.policy_hash_work);
4076 #ifdef CONFIG_XFRM_SUB_POLICY
4077         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4078 #endif
4079         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4080
4081         WARN_ON(!list_empty(&net->xfrm.policy_all));
4082
4083         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4084                 struct xfrm_policy_hash *htab;
4085
4086                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4087
4088                 htab = &net->xfrm.policy_bydst[dir];
4089                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4090                 WARN_ON(!hlist_empty(htab->table));
4091                 xfrm_hash_free(htab->table, sz);
4092         }
4093
4094         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4095         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4096         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4097
4098         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4099         list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4100                 __xfrm_policy_inexact_prune_bin(b, true);
4101         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4102 }
4103
4104 static int __net_init xfrm_net_init(struct net *net)
4105 {
4106         int rv;
4107
4108         /* Initialize the per-net locks here */
4109         spin_lock_init(&net->xfrm.xfrm_state_lock);
4110         spin_lock_init(&net->xfrm.xfrm_policy_lock);
4111         mutex_init(&net->xfrm.xfrm_cfg_mutex);
4112
4113         rv = xfrm_statistics_init(net);
4114         if (rv < 0)
4115                 goto out_statistics;
4116         rv = xfrm_state_init(net);
4117         if (rv < 0)
4118                 goto out_state;
4119         rv = xfrm_policy_init(net);
4120         if (rv < 0)
4121                 goto out_policy;
4122         rv = xfrm_sysctl_init(net);
4123         if (rv < 0)
4124                 goto out_sysctl;
4125
4126         return 0;
4127
4128 out_sysctl:
4129         xfrm_policy_fini(net);
4130 out_policy:
4131         xfrm_state_fini(net);
4132 out_state:
4133         xfrm_statistics_fini(net);
4134 out_statistics:
4135         return rv;
4136 }
4137
4138 static void __net_exit xfrm_net_exit(struct net *net)
4139 {
4140         xfrm_sysctl_fini(net);
4141         xfrm_policy_fini(net);
4142         xfrm_state_fini(net);
4143         xfrm_statistics_fini(net);
4144 }
4145
4146 static struct pernet_operations __net_initdata xfrm_net_ops = {
4147         .init = xfrm_net_init,
4148         .exit = xfrm_net_exit,
4149 };
4150
4151 void __init xfrm_init(void)
4152 {
4153         register_pernet_subsys(&xfrm_net_ops);
4154         xfrm_dev_init();
4155         seqcount_init(&xfrm_policy_hash_generation);
4156         xfrm_input_init();
4157
4158         RCU_INIT_POINTER(xfrm_if_cb, NULL);
4159         synchronize_rcu();
4160 }
4161
4162 #ifdef CONFIG_AUDITSYSCALL
4163 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4164                                          struct audit_buffer *audit_buf)
4165 {
4166         struct xfrm_sec_ctx *ctx = xp->security;
4167         struct xfrm_selector *sel = &xp->selector;
4168
4169         if (ctx)
4170                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4171                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4172
4173         switch (sel->family) {
4174         case AF_INET:
4175                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4176                 if (sel->prefixlen_s != 32)
4177                         audit_log_format(audit_buf, " src_prefixlen=%d",
4178                                          sel->prefixlen_s);
4179                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4180                 if (sel->prefixlen_d != 32)
4181                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4182                                          sel->prefixlen_d);
4183                 break;
4184         case AF_INET6:
4185                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4186                 if (sel->prefixlen_s != 128)
4187                         audit_log_format(audit_buf, " src_prefixlen=%d",
4188                                          sel->prefixlen_s);
4189                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4190                 if (sel->prefixlen_d != 128)
4191                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4192                                          sel->prefixlen_d);
4193                 break;
4194         }
4195 }
4196
4197 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4198 {
4199         struct audit_buffer *audit_buf;
4200
4201         audit_buf = xfrm_audit_start("SPD-add");
4202         if (audit_buf == NULL)
4203                 return;
4204         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4205         audit_log_format(audit_buf, " res=%u", result);
4206         xfrm_audit_common_policyinfo(xp, audit_buf);
4207         audit_log_end(audit_buf);
4208 }
4209 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4210
4211 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4212                               bool task_valid)
4213 {
4214         struct audit_buffer *audit_buf;
4215
4216         audit_buf = xfrm_audit_start("SPD-delete");
4217         if (audit_buf == NULL)
4218                 return;
4219         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4220         audit_log_format(audit_buf, " res=%u", result);
4221         xfrm_audit_common_policyinfo(xp, audit_buf);
4222         audit_log_end(audit_buf);
4223 }
4224 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4225 #endif
4226
4227 #ifdef CONFIG_XFRM_MIGRATE
4228 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4229                                         const struct xfrm_selector *sel_tgt)
4230 {
4231         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4232                 if (sel_tgt->family == sel_cmp->family &&
4233                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4234                                     sel_cmp->family) &&
4235                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4236                                     sel_cmp->family) &&
4237                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4238                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4239                         return true;
4240                 }
4241         } else {
4242                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4243                         return true;
4244                 }
4245         }
4246         return false;
4247 }
4248
4249 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4250                                                     u8 dir, u8 type, struct net *net)
4251 {
4252         struct xfrm_policy *pol, *ret = NULL;
4253         struct hlist_head *chain;
4254         u32 priority = ~0U;
4255
4256         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4257         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4258         hlist_for_each_entry(pol, chain, bydst) {
4259                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4260                     pol->type == type) {
4261                         ret = pol;
4262                         priority = ret->priority;
4263                         break;
4264                 }
4265         }
4266         chain = &net->xfrm.policy_inexact[dir];
4267         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4268                 if ((pol->priority >= priority) && ret)
4269                         break;
4270
4271                 if (xfrm_migrate_selector_match(sel, &pol->selector) &&
4272                     pol->type == type) {
4273                         ret = pol;
4274                         break;
4275                 }
4276         }
4277
4278         xfrm_pol_hold(ret);
4279
4280         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4281
4282         return ret;
4283 }
4284
4285 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4286 {
4287         int match = 0;
4288
4289         if (t->mode == m->mode && t->id.proto == m->proto &&
4290             (m->reqid == 0 || t->reqid == m->reqid)) {
4291                 switch (t->mode) {
4292                 case XFRM_MODE_TUNNEL:
4293                 case XFRM_MODE_BEET:
4294                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4295                                             m->old_family) &&
4296                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
4297                                             m->old_family)) {
4298                                 match = 1;
4299                         }
4300                         break;
4301                 case XFRM_MODE_TRANSPORT:
4302                         /* in case of transport mode, template does not store
4303                            any IP addresses, hence we just compare mode and
4304                            protocol */
4305                         match = 1;
4306                         break;
4307                 default:
4308                         break;
4309                 }
4310         }
4311         return match;
4312 }
4313
4314 /* update endpoint address(es) of template(s) */
4315 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4316                                struct xfrm_migrate *m, int num_migrate)
4317 {
4318         struct xfrm_migrate *mp;
4319         int i, j, n = 0;
4320
4321         write_lock_bh(&pol->lock);
4322         if (unlikely(pol->walk.dead)) {
4323                 /* target policy has been deleted */
4324                 write_unlock_bh(&pol->lock);
4325                 return -ENOENT;
4326         }
4327
4328         for (i = 0; i < pol->xfrm_nr; i++) {
4329                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4330                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4331                                 continue;
4332                         n++;
4333                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4334                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4335                                 continue;
4336                         /* update endpoints */
4337                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4338                                sizeof(pol->xfrm_vec[i].id.daddr));
4339                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4340                                sizeof(pol->xfrm_vec[i].saddr));
4341                         pol->xfrm_vec[i].encap_family = mp->new_family;
4342                         /* flush bundles */
4343                         atomic_inc(&pol->genid);
4344                 }
4345         }
4346
4347         write_unlock_bh(&pol->lock);
4348
4349         if (!n)
4350                 return -ENODATA;
4351
4352         return 0;
4353 }
4354
4355 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
4356 {
4357         int i, j;
4358
4359         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
4360                 return -EINVAL;
4361
4362         for (i = 0; i < num_migrate; i++) {
4363                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4364                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
4365                         return -EINVAL;
4366
4367                 /* check if there is any duplicated entry */
4368                 for (j = i + 1; j < num_migrate; j++) {
4369                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4370                                     sizeof(m[i].old_daddr)) &&
4371                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4372                                     sizeof(m[i].old_saddr)) &&
4373                             m[i].proto == m[j].proto &&
4374                             m[i].mode == m[j].mode &&
4375                             m[i].reqid == m[j].reqid &&
4376                             m[i].old_family == m[j].old_family)
4377                                 return -EINVAL;
4378                 }
4379         }
4380
4381         return 0;
4382 }
4383
4384 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4385                  struct xfrm_migrate *m, int num_migrate,
4386                  struct xfrm_kmaddress *k, struct net *net,
4387                  struct xfrm_encap_tmpl *encap)
4388 {
4389         int i, err, nx_cur = 0, nx_new = 0;
4390         struct xfrm_policy *pol = NULL;
4391         struct xfrm_state *x, *xc;
4392         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4393         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4394         struct xfrm_migrate *mp;
4395
4396         /* Stage 0 - sanity checks */
4397         if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
4398                 goto out;
4399
4400         if (dir >= XFRM_POLICY_MAX) {
4401                 err = -EINVAL;
4402                 goto out;
4403         }
4404
4405         /* Stage 1 - find policy */
4406         if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
4407                 err = -ENOENT;
4408                 goto out;
4409         }
4410
4411         /* Stage 2 - find and update state(s) */
4412         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4413                 if ((x = xfrm_migrate_state_find(mp, net))) {
4414                         x_cur[nx_cur] = x;
4415                         nx_cur++;
4416                         xc = xfrm_state_migrate(x, mp, encap);
4417                         if (xc) {
4418                                 x_new[nx_new] = xc;
4419                                 nx_new++;
4420                         } else {
4421                                 err = -ENODATA;
4422                                 goto restore_state;
4423                         }
4424                 }
4425         }
4426
4427         /* Stage 3 - update policy */
4428         if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
4429                 goto restore_state;
4430
4431         /* Stage 4 - delete old state(s) */
4432         if (nx_cur) {
4433                 xfrm_states_put(x_cur, nx_cur);
4434                 xfrm_states_delete(x_cur, nx_cur);
4435         }
4436
4437         /* Stage 5 - announce */
4438         km_migrate(sel, dir, type, m, num_migrate, k, encap);
4439
4440         xfrm_pol_put(pol);
4441
4442         return 0;
4443 out:
4444         return err;
4445
4446 restore_state:
4447         if (pol)
4448                 xfrm_pol_put(pol);
4449         if (nx_cur)
4450                 xfrm_states_put(x_cur, nx_cur);
4451         if (nx_new)
4452                 xfrm_states_delete(x_new, nx_new);
4453
4454         return err;
4455 }
4456 EXPORT_SYMBOL(xfrm_migrate);
4457 #endif