net/xfrm/xfrm_policy.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * xfrm_policy.c
   4  *
   5  * Changes:
   6  *      Mitsuru KANDA @USAGI
   7  *      Kazunori MIYAZAWA @USAGI
   8  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   9  *              IPv6 support
  10  *      Kazunori MIYAZAWA @USAGI
  11  *      YOSHIFUJI Hideaki
  12  *              Split up af-specific portion
  13  *      Derek Atkins <derek@ihtfp.com>          Add the post_input processor
  14  *
  15  */
  16
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/kmod.h>
  20 #include <linux/list.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/notifier.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/netfilter.h>
  26 #include <linux/module.h>
  27 #include <linux/cache.h>
  28 #include <linux/cpu.h>
  29 #include <linux/audit.h>
  30 #include <linux/rhashtable.h>
  31 #include <linux/if_tunnel.h>
  32 #include <net/dst.h>
  33 #include <net/flow.h>
  34 #include <net/inet_ecn.h>
  35 #include <net/xfrm.h>
  36 #include <net/ip.h>
  37 #include <net/gre.h>
  38 #if IS_ENABLED(CONFIG_IPV6_MIP6)
  39 #include <net/mip6.h>
  40 #endif
  41 #ifdef CONFIG_XFRM_STATISTICS
  42 #include <net/snmp.h>
  43 #endif
  44 #ifdef CONFIG_XFRM_ESPINTCP
  45 #include <net/espintcp.h>
  46 #endif
  47
  48 #include "xfrm_hash.h"
  49
  50 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  51 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  52 #define XFRM_MAX_QUEUE_LEN      100
  53
  54 struct xfrm_flo {
  55         struct dst_entry *dst_orig;
  56         u8 flags;
  57 };
  58
  59 /* prefixes smaller than this are stored in lists, not trees. */
  60 #define INEXACT_PREFIXLEN_IPV4  16
  61 #define INEXACT_PREFIXLEN_IPV6  48
  62
  63 struct xfrm_pol_inexact_node {
  64         struct rb_node node;
  65         union {
  66                 xfrm_address_t addr;
  67                 struct rcu_head rcu;
  68         };
  69         u8 prefixlen;
  70
  71         struct rb_root root;
  72
  73         /* the policies matching this node, can be empty list */
  74         struct hlist_head hhead;
  75 };
  76
  77 /* xfrm inexact policy search tree:
  78  * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
  79  *  |
  80  * +---- root_d: sorted by daddr:prefix
  81  * |                 |
  82  * |        xfrm_pol_inexact_node
  83  * |                 |
  84  * |                 +- root: sorted by saddr/prefix
  85  * |                 |              |
  86  * |                 |         xfrm_pol_inexact_node
  87  * |                 |              |
  88  * |                 |              + root: unused
  89  * |                 |              |
  90  * |                 |              + hhead: saddr:daddr policies
  91  * |                 |
  92  * |                 +- coarse policies and all any:daddr policies
  93  * |
  94  * +---- root_s: sorted by saddr:prefix
  95  * |                 |
  96  * |        xfrm_pol_inexact_node
  97  * |                 |
  98  * |                 + root: unused
  99  * |                 |
 100  * |                 + hhead: saddr:any policies
 101  * |
 102  * +---- coarse policies and all any:any policies
 103  *
 104  * Lookups return four candidate lists:
 105  * 1. any:any list from top-level xfrm_pol_inexact_bin
 106  * 2. any:daddr list from daddr tree
 107  * 3. saddr:daddr list from 2nd level daddr tree
 108  * 4. saddr:any list from saddr tree
 109  *
 110  * This result set then needs to be searched for the policy with
 111  * the lowest priority.  If two results have same prio, youngest one wins.
 112  */
 113
 114 struct xfrm_pol_inexact_key {
 115         possible_net_t net;
 116         u32 if_id;
 117         u16 family;
 118         u8 dir, type;
 119 };
 120
 121 struct xfrm_pol_inexact_bin {
 122         struct xfrm_pol_inexact_key k;
 123         struct rhash_head head;
 124         /* list containing '*:*' policies */
 125         struct hlist_head hhead;
 126
 127         seqcount_spinlock_t count;
 128         /* tree sorted by daddr/prefix */
 129         struct rb_root root_d;
 130
 131         /* tree sorted by saddr/prefix */
 132         struct rb_root root_s;
 133
 134         /* slow path below */
 135         struct list_head inexact_bins;
 136         struct rcu_head rcu;
 137 };
 138
 139 enum xfrm_pol_inexact_candidate_type {
 140         XFRM_POL_CAND_BOTH,
 141         XFRM_POL_CAND_SADDR,
 142         XFRM_POL_CAND_DADDR,
 143         XFRM_POL_CAND_ANY,
 144
 145         XFRM_POL_CAND_MAX,
 146 };
 147
 148 struct xfrm_pol_inexact_candidates {
 149         struct hlist_head *res[XFRM_POL_CAND_MAX];
 150 };
 151
 152 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
 153 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
 154
 155 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
 156 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 157                                                 __read_mostly;
 158
 159 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
 160
 161 static struct rhashtable xfrm_policy_inexact_table;
 162 static const struct rhashtable_params xfrm_pol_inexact_params;
 163
 164 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
 165 static int stale_bundle(struct dst_entry *dst);
 166 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
 167 static void xfrm_policy_queue_process(struct timer_list *t);
 168
 169 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 170 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 171                                                 int dir);
 172
 173 static struct xfrm_pol_inexact_bin *
 174 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
 175                            u32 if_id);
 176
 177 static struct xfrm_pol_inexact_bin *
 178 xfrm_policy_inexact_lookup_rcu(struct net *net,
 179                                u8 type, u16 family, u8 dir, u32 if_id);
 180 static struct xfrm_policy *
 181 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
 182                         bool excl);
 183 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
 184                                             struct xfrm_policy *policy);
 185
 186 static bool
 187 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
 188                                     struct xfrm_pol_inexact_bin *b,
 189                                     const xfrm_address_t *saddr,
 190                                     const xfrm_address_t *daddr);
 191
 192 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
 193 {
 194         return refcount_inc_not_zero(&policy->refcnt);
 195 }
 196
 197 static inline bool
 198 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 199 {
 200         const struct flowi4 *fl4 = &fl->u.ip4;
 201
 202         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
 203                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
 204                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
 205                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
 206                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
 207                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 208 }
 209
 210 static inline bool
 211 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 212 {
 213         const struct flowi6 *fl6 = &fl->u.ip6;
 214
 215         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
 216                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
 217                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
 218                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
 219                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
 220                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 221 }
 222
 223 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
 224                          unsigned short family)
 225 {
 226         switch (family) {
 227         case AF_INET:
 228                 return __xfrm4_selector_match(sel, fl);
 229         case AF_INET6:
 230                 return __xfrm6_selector_match(sel, fl);
 231         }
 232         return false;
 233 }
 234
 235 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 236 {
 237         const struct xfrm_policy_afinfo *afinfo;
 238
 239         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 240                 return NULL;
 241         rcu_read_lock();
 242         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 243         if (unlikely(!afinfo))
 244                 rcu_read_unlock();
 245         return afinfo;
 246 }
 247
 248 /* Called with rcu_read_lock(). */
 249 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 250 {
 251         return rcu_dereference(xfrm_if_cb);
 252 }
 253
 254 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 255                                     const xfrm_address_t *saddr,
 256                                     const xfrm_address_t *daddr,
 257                                     int family, u32 mark)
 258 {
 259         const struct xfrm_policy_afinfo *afinfo;
 260         struct dst_entry *dst;
 261
 262         afinfo = xfrm_policy_get_afinfo(family);
 263         if (unlikely(afinfo == NULL))
 264                 return ERR_PTR(-EAFNOSUPPORT);
 265
 266         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 267
 268         rcu_read_unlock();
 269
 270         return dst;
 271 }
 272 EXPORT_SYMBOL(__xfrm_dst_lookup);
 273
 274 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 275                                                 int tos, int oif,
 276                                                 xfrm_address_t *prev_saddr,
 277                                                 xfrm_address_t *prev_daddr,
 278                                                 int family, u32 mark)
 279 {
 280         struct net *net = xs_net(x);
 281         xfrm_address_t *saddr = &x->props.saddr;
 282         xfrm_address_t *daddr = &x->id.daddr;
 283         struct dst_entry *dst;
 284
 285         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 286                 saddr = x->coaddr;
 287                 daddr = prev_daddr;
 288         }
 289         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 290                 saddr = prev_saddr;
 291                 daddr = x->coaddr;
 292         }
 293
 294         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 295
 296         if (!IS_ERR(dst)) {
 297                 if (prev_saddr != saddr)
 298                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 299                 if (prev_daddr != daddr)
 300                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 301         }
 302
 303         return dst;
 304 }
 305
 306 static inline unsigned long make_jiffies(long secs)
 307 {
 308         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 309                 return MAX_SCHEDULE_TIMEOUT-1;
 310         else
 311                 return secs*HZ;
 312 }
 313
 314 static void xfrm_policy_timer(struct timer_list *t)
 315 {
 316         struct xfrm_policy *xp = from_timer(xp, t, timer);
 317         time64_t now = ktime_get_real_seconds();
 318         time64_t next = TIME64_MAX;
 319         int warn = 0;
 320         int dir;
 321
 322         read_lock(&xp->lock);
 323
 324         if (unlikely(xp->walk.dead))
 325                 goto out;
 326
 327         dir = xfrm_policy_id2dir(xp->index);
 328
 329         if (xp->lft.hard_add_expires_seconds) {
 330                 time64_t tmo = xp->lft.hard_add_expires_seconds +
 331                         xp->curlft.add_time - now;
 332                 if (tmo <= 0)
 333                         goto expired;
 334                 if (tmo < next)
 335                         next = tmo;
 336         }
 337         if (xp->lft.hard_use_expires_seconds) {
 338                 time64_t tmo = xp->lft.hard_use_expires_seconds +
 339                         (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 340                 if (tmo <= 0)
 341                         goto expired;
 342                 if (tmo < next)
 343                         next = tmo;
 344         }
 345         if (xp->lft.soft_add_expires_seconds) {
 346                 time64_t tmo = xp->lft.soft_add_expires_seconds +
 347                         xp->curlft.add_time - now;
 348                 if (tmo <= 0) {
 349                         warn = 1;
 350                         tmo = XFRM_KM_TIMEOUT;
 351                 }
 352                 if (tmo < next)
 353                         next = tmo;
 354         }
 355         if (xp->lft.soft_use_expires_seconds) {
 356                 time64_t tmo = xp->lft.soft_use_expires_seconds +
 357                         (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 358                 if (tmo <= 0) {
 359                         warn = 1;
 360                         tmo = XFRM_KM_TIMEOUT;
 361                 }
 362                 if (tmo < next)
 363                         next = tmo;
 364         }
 365
 366         if (warn)
 367                 km_policy_expired(xp, dir, 0, 0);
 368         if (next != TIME64_MAX &&
 369             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 370                 xfrm_pol_hold(xp);
 371
 372 out:
 373         read_unlock(&xp->lock);
 374         xfrm_pol_put(xp);
 375         return;
 376
 377 expired:
 378         read_unlock(&xp->lock);
 379         if (!xfrm_policy_delete(xp, dir))
 380                 km_policy_expired(xp, dir, 1, 0);
 381         xfrm_pol_put(xp);
 382 }
 383
 384 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 385  * SPD calls.
 386  */
 387
 388 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 389 {
 390         struct xfrm_policy *policy;
 391
 392         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 393
 394         if (policy) {
 395                 write_pnet(&policy->xp_net, net);
 396                 INIT_LIST_HEAD(&policy->walk.all);
 397                 INIT_HLIST_NODE(&policy->bydst_inexact_list);
 398                 INIT_HLIST_NODE(&policy->bydst);
 399                 INIT_HLIST_NODE(&policy->byidx);
 400                 rwlock_init(&policy->lock);
 401                 refcount_set(&policy->refcnt, 1);
 402                 skb_queue_head_init(&policy->polq.hold_queue);
 403                 timer_setup(&policy->timer, xfrm_policy_timer, 0);
 404                 timer_setup(&policy->polq.hold_timer,
 405                             xfrm_policy_queue_process, 0);
 406         }
 407         return policy;
 408 }
 409 EXPORT_SYMBOL(xfrm_policy_alloc);
 410
 411 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 412 {
 413         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 414
 415         security_xfrm_policy_free(policy->security);
 416         kfree(policy);
 417 }
 418
 419 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 420
 421 void xfrm_policy_destroy(struct xfrm_policy *policy)
 422 {
 423         BUG_ON(!policy->walk.dead);
 424
 425         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 426                 BUG();
 427
 428         xfrm_dev_policy_free(policy);
 429         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 430 }
 431 EXPORT_SYMBOL(xfrm_policy_destroy);
 432
 433 /* Rule must be locked. Release descendant resources, announce
 434  * entry dead. The rule must be unlinked from lists to the moment.
 435  */
 436
 437 static void xfrm_policy_kill(struct xfrm_policy *policy)
 438 {
 439         write_lock_bh(&policy->lock);
 440         policy->walk.dead = 1;
 441         write_unlock_bh(&policy->lock);
 442
 443         atomic_inc(&policy->genid);
 444
 445         if (del_timer(&policy->polq.hold_timer))
 446                 xfrm_pol_put(policy);
 447         skb_queue_purge(&policy->polq.hold_queue);
 448
 449         if (del_timer(&policy->timer))
 450                 xfrm_pol_put(policy);
 451
 452         xfrm_pol_put(policy);
 453 }
 454
 455 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 456
 457 static inline unsigned int idx_hash(struct net *net, u32 index)
 458 {
 459         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 460 }
 461
 462 /* calculate policy hash thresholds */
 463 static void __get_hash_thresh(struct net *net,
 464                               unsigned short family, int dir,
 465                               u8 *dbits, u8 *sbits)
 466 {
 467         switch (family) {
 468         case AF_INET:
 469                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 470                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 471                 break;
 472
 473         case AF_INET6:
 474                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 475                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 476                 break;
 477
 478         default:
 479                 *dbits = 0;
 480                 *sbits = 0;
 481         }
 482 }
 483
 484 static struct hlist_head *policy_hash_bysel(struct net *net,
 485                                             const struct xfrm_selector *sel,
 486                                             unsigned short family, int dir)
 487 {
 488         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 489         unsigned int hash;
 490         u8 dbits;
 491         u8 sbits;
 492
 493         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 494         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 495
 496         if (hash == hmask + 1)
 497                 return NULL;
 498
 499         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 500                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 501 }
 502
 503 static struct hlist_head *policy_hash_direct(struct net *net,
 504                                              const xfrm_address_t *daddr,
 505                                              const xfrm_address_t *saddr,
 506                                              unsigned short family, int dir)
 507 {
 508         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 509         unsigned int hash;
 510         u8 dbits;
 511         u8 sbits;
 512
 513         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 514         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 515
 516         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 517                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 518 }
 519
 520 static void xfrm_dst_hash_transfer(struct net *net,
 521                                    struct hlist_head *list,
 522                                    struct hlist_head *ndsttable,
 523                                    unsigned int nhashmask,
 524                                    int dir)
 525 {
 526         struct hlist_node *tmp, *entry0 = NULL;
 527         struct xfrm_policy *pol;
 528         unsigned int h0 = 0;
 529         u8 dbits;
 530         u8 sbits;
 531
 532 redo:
 533         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 534                 unsigned int h;
 535
 536                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 537                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 538                                 pol->family, nhashmask, dbits, sbits);
 539                 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) {
 540                         hlist_del_rcu(&pol->bydst);
 541                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 542                         h0 = h;
 543                 } else {
 544                         if (h != h0)
 545                                 continue;
 546                         hlist_del_rcu(&pol->bydst);
 547                         hlist_add_behind_rcu(&pol->bydst, entry0);
 548                 }
 549                 entry0 = &pol->bydst;
 550         }
 551         if (!hlist_empty(list)) {
 552                 entry0 = NULL;
 553                 goto redo;
 554         }
 555 }
 556
 557 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 558                                    struct hlist_head *nidxtable,
 559                                    unsigned int nhashmask)
 560 {
 561         struct hlist_node *tmp;
 562         struct xfrm_policy *pol;
 563
 564         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 565                 unsigned int h;
 566
 567                 h = __idx_hash(pol->index, nhashmask);
 568                 hlist_add_head(&pol->byidx, nidxtable+h);
 569         }
 570 }
 571
 572 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 573 {
 574         return ((old_hmask + 1) << 1) - 1;
 575 }
 576
 577 static void xfrm_bydst_resize(struct net *net, int dir)
 578 {
 579         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 580         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 581         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 582         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 583         struct hlist_head *odst;
 584         int i;
 585
 586         if (!ndst)
 587                 return;
 588
 589         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 590         write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
 591
 592         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 593                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 594
 595         for (i = hmask; i >= 0; i--)
 596                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 597
 598         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 599         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 600
 601         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
 602         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 603
 604         synchronize_rcu();
 605
 606         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 607 }
 608
 609 static void xfrm_byidx_resize(struct net *net)
 610 {
 611         unsigned int hmask = net->xfrm.policy_idx_hmask;
 612         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 613         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 614         struct hlist_head *oidx = net->xfrm.policy_byidx;
 615         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 616         int i;
 617
 618         if (!nidx)
 619                 return;
 620
 621         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 622
 623         for (i = hmask; i >= 0; i--)
 624                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 625
 626         net->xfrm.policy_byidx = nidx;
 627         net->xfrm.policy_idx_hmask = nhashmask;
 628
 629         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 630
 631         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 632 }
 633
 634 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 635 {
 636         unsigned int cnt = net->xfrm.policy_count[dir];
 637         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 638
 639         if (total)
 640                 *total += cnt;
 641
 642         if ((hmask + 1) < xfrm_policy_hashmax &&
 643             cnt > hmask)
 644                 return 1;
 645
 646         return 0;
 647 }
 648
 649 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 650 {
 651         unsigned int hmask = net->xfrm.policy_idx_hmask;
 652
 653         if ((hmask + 1) < xfrm_policy_hashmax &&
 654             total > hmask)
 655                 return 1;
 656
 657         return 0;
 658 }
 659
 660 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 661 {
 662         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 663         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 664         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 665         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 666         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 667         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 668         si->spdhcnt = net->xfrm.policy_idx_hmask;
 669         si->spdhmcnt = xfrm_policy_hashmax;
 670 }
 671 EXPORT_SYMBOL(xfrm_spd_getinfo);
 672
 673 static DEFINE_MUTEX(hash_resize_mutex);
 674 static void xfrm_hash_resize(struct work_struct *work)
 675 {
 676         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 677         int dir, total;
 678
 679         mutex_lock(&hash_resize_mutex);
 680
 681         total = 0;
 682         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 683                 if (xfrm_bydst_should_resize(net, dir, &total))
 684                         xfrm_bydst_resize(net, dir);
 685         }
 686         if (xfrm_byidx_should_resize(net, total))
 687                 xfrm_byidx_resize(net);
 688
 689         mutex_unlock(&hash_resize_mutex);
 690 }
 691
 692 /* Make sure *pol can be inserted into fastbin.
 693  * Useful to check that later insert requests will be successful
 694  * (provided xfrm_policy_lock is held throughout).
 695  */
 696 static struct xfrm_pol_inexact_bin *
 697 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
 698 {
 699         struct xfrm_pol_inexact_bin *bin, *prev;
 700         struct xfrm_pol_inexact_key k = {
 701                 .family = pol->family,
 702                 .type = pol->type,
 703                 .dir = dir,
 704                 .if_id = pol->if_id,
 705         };
 706         struct net *net = xp_net(pol);
 707
 708         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
 709
 710         write_pnet(&k.net, net);
 711         bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
 712                                      xfrm_pol_inexact_params);
 713         if (bin)
 714                 return bin;
 715
 716         bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
 717         if (!bin)
 718                 return NULL;
 719
 720         bin->k = k;
 721         INIT_HLIST_HEAD(&bin->hhead);
 722         bin->root_d = RB_ROOT;
 723         bin->root_s = RB_ROOT;
 724         seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
 725
 726         prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
 727                                                 &bin->k, &bin->head,
 728                                                 xfrm_pol_inexact_params);
 729         if (!prev) {
 730                 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
 731                 return bin;
 732         }
 733
 734         kfree(bin);
 735
 736         return IS_ERR(prev) ? NULL : prev;
 737 }
 738
 739 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
 740                                                int family, u8 prefixlen)
 741 {
 742         if (xfrm_addr_any(addr, family))
 743                 return true;
 744
 745         if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
 746                 return true;
 747
 748         if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
 749                 return true;
 750
 751         return false;
 752 }
 753
 754 static bool
 755 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
 756 {
 757         const xfrm_address_t *addr;
 758         bool saddr_any, daddr_any;
 759         u8 prefixlen;
 760
 761         addr = &policy->selector.saddr;
 762         prefixlen = policy->selector.prefixlen_s;
 763
 764         saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 765                                                        policy->family,
 766                                                        prefixlen);
 767         addr = &policy->selector.daddr;
 768         prefixlen = policy->selector.prefixlen_d;
 769         daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 770                                                        policy->family,
 771                                                        prefixlen);
 772         return saddr_any && daddr_any;
 773 }
 774
 775 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
 776                                        const xfrm_address_t *addr, u8 prefixlen)
 777 {
 778         node->addr = *addr;
 779         node->prefixlen = prefixlen;
 780 }
 781
 782 static struct xfrm_pol_inexact_node *
 783 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
 784 {
 785         struct xfrm_pol_inexact_node *node;
 786
 787         node = kzalloc(sizeof(*node), GFP_ATOMIC);
 788         if (node)
 789                 xfrm_pol_inexact_node_init(node, addr, prefixlen);
 790
 791         return node;
 792 }
 793
 794 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
 795                                   const xfrm_address_t *b,
 796                                   u8 prefixlen, u16 family)
 797 {
 798         u32 ma, mb, mask;
 799         unsigned int pdw, pbi;
 800         int delta = 0;
 801
 802         switch (family) {
 803         case AF_INET:
 804                 if (prefixlen == 0)
 805                         return 0;
 806                 mask = ~0U << (32 - prefixlen);
 807                 ma = ntohl(a->a4) & mask;
 808                 mb = ntohl(b->a4) & mask;
 809                 if (ma < mb)
 810                         delta = -1;
 811                 else if (ma > mb)
 812                         delta = 1;
 813                 break;
 814         case AF_INET6:
 815                 pdw = prefixlen >> 5;
 816                 pbi = prefixlen & 0x1f;
 817
 818                 if (pdw) {
 819                         delta = memcmp(a->a6, b->a6, pdw << 2);
 820                         if (delta)
 821                                 return delta;
 822                 }
 823                 if (pbi) {
 824                         mask = ~0U << (32 - pbi);
 825                         ma = ntohl(a->a6[pdw]) & mask;
 826                         mb = ntohl(b->a6[pdw]) & mask;
 827                         if (ma < mb)
 828                                 delta = -1;
 829                         else if (ma > mb)
 830                                 delta = 1;
 831                 }
 832                 break;
 833         default:
 834                 break;
 835         }
 836
 837         return delta;
 838 }
 839
 840 static void xfrm_policy_inexact_list_reinsert(struct net *net,
 841                                               struct xfrm_pol_inexact_node *n,
 842                                               u16 family)
 843 {
 844         unsigned int matched_s, matched_d;
 845         struct xfrm_policy *policy, *p;
 846
 847         matched_s = 0;
 848         matched_d = 0;
 849
 850         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 851                 struct hlist_node *newpos = NULL;
 852                 bool matches_s, matches_d;
 853
 854                 if (!policy->bydst_reinsert)
 855                         continue;
 856
 857                 WARN_ON_ONCE(policy->family != family);
 858
 859                 policy->bydst_reinsert = false;
 860                 hlist_for_each_entry(p, &n->hhead, bydst) {
 861                         if (policy->priority > p->priority)
 862                                 newpos = &p->bydst;
 863                         else if (policy->priority == p->priority &&
 864                                  policy->pos > p->pos)
 865                                 newpos = &p->bydst;
 866                         else
 867                                 break;
 868                 }
 869
 870                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
 871                         hlist_add_behind_rcu(&policy->bydst, newpos);
 872                 else
 873                         hlist_add_head_rcu(&policy->bydst, &n->hhead);
 874
 875                 /* paranoia checks follow.
 876                  * Check that the reinserted policy matches at least
 877                  * saddr or daddr for current node prefix.
 878                  *
 879                  * Matching both is fine, matching saddr in one policy
 880                  * (but not daddr) and then matching only daddr in another
 881                  * is a bug.
 882                  */
 883                 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
 884                                                    &n->addr,
 885                                                    n->prefixlen,
 886                                                    family) == 0;
 887                 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
 888                                                    &n->addr,
 889                                                    n->prefixlen,
 890                                                    family) == 0;
 891                 if (matches_s && matches_d)
 892                         continue;
 893
 894                 WARN_ON_ONCE(!matches_s && !matches_d);
 895                 if (matches_s)
 896                         matched_s++;
 897                 if (matches_d)
 898                         matched_d++;
 899                 WARN_ON_ONCE(matched_s && matched_d);
 900         }
 901 }
 902
 903 static void xfrm_policy_inexact_node_reinsert(struct net *net,
 904                                               struct xfrm_pol_inexact_node *n,
 905                                               struct rb_root *new,
 906                                               u16 family)
 907 {
 908         struct xfrm_pol_inexact_node *node;
 909         struct rb_node **p, *parent;
 910
 911         /* we should not have another subtree here */
 912         WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
 913 restart:
 914         parent = NULL;
 915         p = &new->rb_node;
 916         while (*p) {
 917                 u8 prefixlen;
 918                 int delta;
 919
 920                 parent = *p;
 921                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 922
 923                 prefixlen = min(node->prefixlen, n->prefixlen);
 924
 925                 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
 926                                                prefixlen, family);
 927                 if (delta < 0) {
 928                         p = &parent->rb_left;
 929                 } else if (delta > 0) {
 930                         p = &parent->rb_right;
 931                 } else {
 932                         bool same_prefixlen = node->prefixlen == n->prefixlen;
 933                         struct xfrm_policy *tmp;
 934
 935                         hlist_for_each_entry(tmp, &n->hhead, bydst) {
 936                                 tmp->bydst_reinsert = true;
 937                                 hlist_del_rcu(&tmp->bydst);
 938                         }
 939
 940                         node->prefixlen = prefixlen;
 941
 942                         xfrm_policy_inexact_list_reinsert(net, node, family);
 943
 944                         if (same_prefixlen) {
 945                                 kfree_rcu(n, rcu);
 946                                 return;
 947                         }
 948
 949                         rb_erase(*p, new);
 950                         kfree_rcu(n, rcu);
 951                         n = node;
 952                         goto restart;
 953                 }
 954         }
 955
 956         rb_link_node_rcu(&n->node, parent, p);
 957         rb_insert_color(&n->node, new);
 958 }
 959
 960 /* merge nodes v and n */
 961 static void xfrm_policy_inexact_node_merge(struct net *net,
 962                                            struct xfrm_pol_inexact_node *v,
 963                                            struct xfrm_pol_inexact_node *n,
 964                                            u16 family)
 965 {
 966         struct xfrm_pol_inexact_node *node;
 967         struct xfrm_policy *tmp;
 968         struct rb_node *rnode;
 969
 970         /* To-be-merged node v has a subtree.
 971          *
 972          * Dismantle it and insert its nodes to n->root.
 973          */
 974         while ((rnode = rb_first(&v->root)) != NULL) {
 975                 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
 976                 rb_erase(&node->node, &v->root);
 977                 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
 978                                                   family);
 979         }
 980
 981         hlist_for_each_entry(tmp, &v->hhead, bydst) {
 982                 tmp->bydst_reinsert = true;
 983                 hlist_del_rcu(&tmp->bydst);
 984         }
 985
 986         xfrm_policy_inexact_list_reinsert(net, n, family);
 987 }
 988
 989 static struct xfrm_pol_inexact_node *
 990 xfrm_policy_inexact_insert_node(struct net *net,
 991                                 struct rb_root *root,
 992                                 xfrm_address_t *addr,
 993                                 u16 family, u8 prefixlen, u8 dir)
 994 {
 995         struct xfrm_pol_inexact_node *cached = NULL;
 996         struct rb_node **p, *parent = NULL;
 997         struct xfrm_pol_inexact_node *node;
 998
 999         p = &root->rb_node;
1000         while (*p) {
1001                 int delta;
1002
1003                 parent = *p;
1004                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
1005
1006                 delta = xfrm_policy_addr_delta(addr, &node->addr,
1007                                                node->prefixlen,
1008                                                family);
1009                 if (delta == 0 && prefixlen >= node->prefixlen) {
1010                         WARN_ON_ONCE(cached); /* ipsec policies got lost */
1011                         return node;
1012                 }
1013
1014                 if (delta < 0)
1015                         p = &parent->rb_left;
1016                 else
1017                         p = &parent->rb_right;
1018
1019                 if (prefixlen < node->prefixlen) {
1020                         delta = xfrm_policy_addr_delta(addr, &node->addr,
1021                                                        prefixlen,
1022                                                        family);
1023                         if (delta)
1024                                 continue;
1025
1026                         /* This node is a subnet of the new prefix. It needs
1027                          * to be removed and re-inserted with the smaller
1028                          * prefix and all nodes that are now also covered
1029                          * by the reduced prefixlen.
1030                          */
1031                         rb_erase(&node->node, root);
1032
1033                         if (!cached) {
1034                                 xfrm_pol_inexact_node_init(node, addr,
1035                                                            prefixlen);
1036                                 cached = node;
1037                         } else {
1038                                 /* This node also falls within the new
1039                                  * prefixlen. Merge the to-be-reinserted
1040                                  * node and this one.
1041                                  */
1042                                 xfrm_policy_inexact_node_merge(net, node,
1043                                                                cached, family);
1044                                 kfree_rcu(node, rcu);
1045                         }
1046
1047                         /* restart */
1048                         p = &root->rb_node;
1049                         parent = NULL;
1050                 }
1051         }
1052
1053         node = cached;
1054         if (!node) {
1055                 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1056                 if (!node)
1057                         return NULL;
1058         }
1059
1060         rb_link_node_rcu(&node->node, parent, p);
1061         rb_insert_color(&node->node, root);
1062
1063         return node;
1064 }
1065
1066 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1067 {
1068         struct xfrm_pol_inexact_node *node;
1069         struct rb_node *rn = rb_first(r);
1070
1071         while (rn) {
1072                 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1073
1074                 xfrm_policy_inexact_gc_tree(&node->root, rm);
1075                 rn = rb_next(rn);
1076
1077                 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1078                         WARN_ON_ONCE(rm);
1079                         continue;
1080                 }
1081
1082                 rb_erase(&node->node, r);
1083                 kfree_rcu(node, rcu);
1084         }
1085 }
1086
1087 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1088 {
1089         write_seqcount_begin(&b->count);
1090         xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1091         xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1092         write_seqcount_end(&b->count);
1093
1094         if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1095             !hlist_empty(&b->hhead)) {
1096                 WARN_ON_ONCE(net_exit);
1097                 return;
1098         }
1099
1100         if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1101                                    xfrm_pol_inexact_params) == 0) {
1102                 list_del(&b->inexact_bins);
1103                 kfree_rcu(b, rcu);
1104         }
1105 }
1106
1107 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1108 {
1109         struct net *net = read_pnet(&b->k.net);
1110
1111         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1112         __xfrm_policy_inexact_prune_bin(b, false);
1113         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1114 }
1115
1116 static void __xfrm_policy_inexact_flush(struct net *net)
1117 {
1118         struct xfrm_pol_inexact_bin *bin, *t;
1119
1120         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1121
1122         list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1123                 __xfrm_policy_inexact_prune_bin(bin, false);
1124 }
1125
1126 static struct hlist_head *
1127 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1128                                 struct xfrm_policy *policy, u8 dir)
1129 {
1130         struct xfrm_pol_inexact_node *n;
1131         struct net *net;
1132
1133         net = xp_net(policy);
1134         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1135
1136         if (xfrm_policy_inexact_insert_use_any_list(policy))
1137                 return &bin->hhead;
1138
1139         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1140                                                policy->family,
1141                                                policy->selector.prefixlen_d)) {
1142                 write_seqcount_begin(&bin->count);
1143                 n = xfrm_policy_inexact_insert_node(net,
1144                                                     &bin->root_s,
1145                                                     &policy->selector.saddr,
1146                                                     policy->family,
1147                                                     policy->selector.prefixlen_s,
1148                                                     dir);
1149                 write_seqcount_end(&bin->count);
1150                 if (!n)
1151                         return NULL;
1152
1153                 return &n->hhead;
1154         }
1155
1156         /* daddr is fixed */
1157         write_seqcount_begin(&bin->count);
1158         n = xfrm_policy_inexact_insert_node(net,
1159                                             &bin->root_d,
1160                                             &policy->selector.daddr,
1161                                             policy->family,
1162                                             policy->selector.prefixlen_d, dir);
1163         write_seqcount_end(&bin->count);
1164         if (!n)
1165                 return NULL;
1166
1167         /* saddr is wildcard */
1168         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1169                                                policy->family,
1170                                                policy->selector.prefixlen_s))
1171                 return &n->hhead;
1172
1173         write_seqcount_begin(&bin->count);
1174         n = xfrm_policy_inexact_insert_node(net,
1175                                             &n->root,
1176                                             &policy->selector.saddr,
1177                                             policy->family,
1178                                             policy->selector.prefixlen_s, dir);
1179         write_seqcount_end(&bin->count);
1180         if (!n)
1181                 return NULL;
1182
1183         return &n->hhead;
1184 }
1185
1186 static struct xfrm_policy *
1187 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1188 {
1189         struct xfrm_pol_inexact_bin *bin;
1190         struct xfrm_policy *delpol;
1191         struct hlist_head *chain;
1192         struct net *net;
1193
1194         bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1195         if (!bin)
1196                 return ERR_PTR(-ENOMEM);
1197
1198         net = xp_net(policy);
1199         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1200
1201         chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1202         if (!chain) {
1203                 __xfrm_policy_inexact_prune_bin(bin, false);
1204                 return ERR_PTR(-ENOMEM);
1205         }
1206
1207         delpol = xfrm_policy_insert_list(chain, policy, excl);
1208         if (delpol && excl) {
1209                 __xfrm_policy_inexact_prune_bin(bin, false);
1210                 return ERR_PTR(-EEXIST);
1211         }
1212
1213         chain = &net->xfrm.policy_inexact[dir];
1214         xfrm_policy_insert_inexact_list(chain, policy);
1215
1216         if (delpol)
1217                 __xfrm_policy_inexact_prune_bin(bin, false);
1218
1219         return delpol;
1220 }
1221
1222 static void xfrm_hash_rebuild(struct work_struct *work)
1223 {
1224         struct net *net = container_of(work, struct net,
1225                                        xfrm.policy_hthresh.work);
1226         unsigned int hmask;
1227         struct xfrm_policy *pol;
1228         struct xfrm_policy *policy;
1229         struct hlist_head *chain;
1230         struct hlist_head *odst;
1231         struct hlist_node *newpos;
1232         int i;
1233         int dir;
1234         unsigned seq;
1235         u8 lbits4, rbits4, lbits6, rbits6;
1236
1237         mutex_lock(&hash_resize_mutex);
1238
1239         /* read selector prefixlen thresholds */
1240         do {
1241                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1242
1243                 lbits4 = net->xfrm.policy_hthresh.lbits4;
1244                 rbits4 = net->xfrm.policy_hthresh.rbits4;
1245                 lbits6 = net->xfrm.policy_hthresh.lbits6;
1246                 rbits6 = net->xfrm.policy_hthresh.rbits6;
1247         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1248
1249         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1250         write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
1251
1252         /* make sure that we can insert the indirect policies again before
1253          * we start with destructive action.
1254          */
1255         list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1256                 struct xfrm_pol_inexact_bin *bin;
1257                 u8 dbits, sbits;
1258
1259                 dir = xfrm_policy_id2dir(policy->index);
1260                 if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1261                         continue;
1262
1263                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1264                         if (policy->family == AF_INET) {
1265                                 dbits = rbits4;
1266                                 sbits = lbits4;
1267                         } else {
1268                                 dbits = rbits6;
1269                                 sbits = lbits6;
1270                         }
1271                 } else {
1272                         if (policy->family == AF_INET) {
1273                                 dbits = lbits4;
1274                                 sbits = rbits4;
1275                         } else {
1276                                 dbits = lbits6;
1277                                 sbits = rbits6;
1278                         }
1279                 }
1280
1281                 if (policy->selector.prefixlen_d < dbits ||
1282                     policy->selector.prefixlen_s < sbits)
1283                         continue;
1284
1285                 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1286                 if (!bin)
1287                         goto out_unlock;
1288
1289                 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1290                         goto out_unlock;
1291         }
1292
1293         /* reset the bydst and inexact table in all directions */
1294         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1295                 struct hlist_node *n;
1296
1297                 hlist_for_each_entry_safe(policy, n,
1298                                           &net->xfrm.policy_inexact[dir],
1299                                           bydst_inexact_list) {
1300                         hlist_del_rcu(&policy->bydst);
1301                         hlist_del_init(&policy->bydst_inexact_list);
1302                 }
1303
1304                 hmask = net->xfrm.policy_bydst[dir].hmask;
1305                 odst = net->xfrm.policy_bydst[dir].table;
1306                 for (i = hmask; i >= 0; i--) {
1307                         hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1308                                 hlist_del_rcu(&policy->bydst);
1309                 }
1310                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1311                         /* dir out => dst = remote, src = local */
1312                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1313                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1314                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1315                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1316                 } else {
1317                         /* dir in/fwd => dst = local, src = remote */
1318                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1319                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1320                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1321                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1322                 }
1323         }
1324
1325         /* re-insert all policies by order of creation */
1326         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1327                 if (policy->walk.dead)
1328                         continue;
1329                 dir = xfrm_policy_id2dir(policy->index);
1330                 if (dir >= XFRM_POLICY_MAX) {
1331                         /* skip socket policies */
1332                         continue;
1333                 }
1334                 newpos = NULL;
1335                 chain = policy_hash_bysel(net, &policy->selector,
1336                                           policy->family, dir);
1337
1338                 if (!chain) {
1339                         void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1340
1341                         WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1342                         continue;
1343                 }
1344
1345                 hlist_for_each_entry(pol, chain, bydst) {
1346                         if (policy->priority >= pol->priority)
1347                                 newpos = &pol->bydst;
1348                         else
1349                                 break;
1350                 }
1351                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1352                         hlist_add_behind_rcu(&policy->bydst, newpos);
1353                 else
1354                         hlist_add_head_rcu(&policy->bydst, chain);
1355         }
1356
1357 out_unlock:
1358         __xfrm_policy_inexact_flush(net);
1359         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1360         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1361
1362         mutex_unlock(&hash_resize_mutex);
1363 }
1364
1365 void xfrm_policy_hash_rebuild(struct net *net)
1366 {
1367         schedule_work(&net->xfrm.policy_hthresh.work);
1368 }
1369 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1370
1371 /* Generate new index... KAME seems to generate them ordered by cost
1372  * of an absolute inpredictability of ordering of rules. This will not pass. */
1373 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1374 {
1375         static u32 idx_generator;
1376
1377         for (;;) {
1378                 struct hlist_head *list;
1379                 struct xfrm_policy *p;
1380                 u32 idx;
1381                 int found;
1382
1383                 if (!index) {
1384                         idx = (idx_generator | dir);
1385                         idx_generator += 8;
1386                 } else {
1387                         idx = index;
1388                         index = 0;
1389                 }
1390
1391                 if (idx == 0)
1392                         idx = 8;
1393                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1394                 found = 0;
1395                 hlist_for_each_entry(p, list, byidx) {
1396                         if (p->index == idx) {
1397                                 found = 1;
1398                                 break;
1399                         }
1400                 }
1401                 if (!found)
1402                         return idx;
1403         }
1404 }
1405
1406 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1407 {
1408         u32 *p1 = (u32 *) s1;
1409         u32 *p2 = (u32 *) s2;
1410         int len = sizeof(struct xfrm_selector) / sizeof(u32);
1411         int i;
1412
1413         for (i = 0; i < len; i++) {
1414                 if (p1[i] != p2[i])
1415                         return 1;
1416         }
1417
1418         return 0;
1419 }
1420
1421 static void xfrm_policy_requeue(struct xfrm_policy *old,
1422                                 struct xfrm_policy *new)
1423 {
1424         struct xfrm_policy_queue *pq = &old->polq;
1425         struct sk_buff_head list;
1426
1427         if (skb_queue_empty(&pq->hold_queue))
1428                 return;
1429
1430         __skb_queue_head_init(&list);
1431
1432         spin_lock_bh(&pq->hold_queue.lock);
1433         skb_queue_splice_init(&pq->hold_queue, &list);
1434         if (del_timer(&pq->hold_timer))
1435                 xfrm_pol_put(old);
1436         spin_unlock_bh(&pq->hold_queue.lock);
1437
1438         pq = &new->polq;
1439
1440         spin_lock_bh(&pq->hold_queue.lock);
1441         skb_queue_splice(&list, &pq->hold_queue);
1442         pq->timeout = XFRM_QUEUE_TMO_MIN;
1443         if (!mod_timer(&pq->hold_timer, jiffies))
1444                 xfrm_pol_hold(new);
1445         spin_unlock_bh(&pq->hold_queue.lock);
1446 }
1447
1448 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1449                                           struct xfrm_policy *pol)
1450 {
1451         return mark->v == pol->mark.v && mark->m == pol->mark.m;
1452 }
1453
1454 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1455 {
1456         const struct xfrm_pol_inexact_key *k = data;
1457         u32 a = k->type << 24 | k->dir << 16 | k->family;
1458
1459         return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1460                             seed);
1461 }
1462
1463 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1464 {
1465         const struct xfrm_pol_inexact_bin *b = data;
1466
1467         return xfrm_pol_bin_key(&b->k, 0, seed);
1468 }
1469
1470 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1471                             const void *ptr)
1472 {
1473         const struct xfrm_pol_inexact_key *key = arg->key;
1474         const struct xfrm_pol_inexact_bin *b = ptr;
1475         int ret;
1476
1477         if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1478                 return -1;
1479
1480         ret = b->k.dir ^ key->dir;
1481         if (ret)
1482                 return ret;
1483
1484         ret = b->k.type ^ key->type;
1485         if (ret)
1486                 return ret;
1487
1488         ret = b->k.family ^ key->family;
1489         if (ret)
1490                 return ret;
1491
1492         return b->k.if_id ^ key->if_id;
1493 }
1494
1495 static const struct rhashtable_params xfrm_pol_inexact_params = {
1496         .head_offset            = offsetof(struct xfrm_pol_inexact_bin, head),
1497         .hashfn                 = xfrm_pol_bin_key,
1498         .obj_hashfn             = xfrm_pol_bin_obj,
1499         .obj_cmpfn              = xfrm_pol_bin_cmp,
1500         .automatic_shrinking    = true,
1501 };
1502
1503 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1504                                             struct xfrm_policy *policy)
1505 {
1506         struct xfrm_policy *pol, *delpol = NULL;
1507         struct hlist_node *newpos = NULL;
1508         int i = 0;
1509
1510         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1511                 if (pol->type == policy->type &&
1512                     pol->if_id == policy->if_id &&
1513                     !selector_cmp(&pol->selector, &policy->selector) &&
1514                     xfrm_policy_mark_match(&policy->mark, pol) &&
1515                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1516                     !WARN_ON(delpol)) {
1517                         delpol = pol;
1518                         if (policy->priority > pol->priority)
1519                                 continue;
1520                 } else if (policy->priority >= pol->priority) {
1521                         newpos = &pol->bydst_inexact_list;
1522                         continue;
1523                 }
1524                 if (delpol)
1525                         break;
1526         }
1527
1528         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1529                 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1530         else
1531                 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1532
1533         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1534                 pol->pos = i;
1535                 i++;
1536         }
1537 }
1538
1539 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1540                                                    struct xfrm_policy *policy,
1541                                                    bool excl)
1542 {
1543         struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1544
1545         hlist_for_each_entry(pol, chain, bydst) {
1546                 if (pol->type == policy->type &&
1547                     pol->if_id == policy->if_id &&
1548                     !selector_cmp(&pol->selector, &policy->selector) &&
1549                     xfrm_policy_mark_match(&policy->mark, pol) &&
1550                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1551                     !WARN_ON(delpol)) {
1552                         if (excl)
1553                                 return ERR_PTR(-EEXIST);
1554                         delpol = pol;
1555                         if (policy->priority > pol->priority)
1556                                 continue;
1557                 } else if (policy->priority >= pol->priority) {
1558                         newpos = pol;
1559                         continue;
1560                 }
1561                 if (delpol)
1562                         break;
1563         }
1564
1565         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1566                 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1567         else
1568                 /* Packet offload policies enter to the head
1569                  * to speed-up lookups.
1570                  */
1571                 hlist_add_head_rcu(&policy->bydst, chain);
1572
1573         return delpol;
1574 }
1575
1576 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1577 {
1578         struct net *net = xp_net(policy);
1579         struct xfrm_policy *delpol;
1580         struct hlist_head *chain;
1581
1582         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1583         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1584         if (chain)
1585                 delpol = xfrm_policy_insert_list(chain, policy, excl);
1586         else
1587                 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1588
1589         if (IS_ERR(delpol)) {
1590                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1591                 return PTR_ERR(delpol);
1592         }
1593
1594         __xfrm_policy_link(policy, dir);
1595
1596         /* After previous checking, family can either be AF_INET or AF_INET6 */
1597         if (policy->family == AF_INET)
1598                 rt_genid_bump_ipv4(net);
1599         else
1600                 rt_genid_bump_ipv6(net);
1601
1602         if (delpol) {
1603                 xfrm_policy_requeue(delpol, policy);
1604                 __xfrm_policy_unlink(delpol, dir);
1605         }
1606         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1607         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1608         policy->curlft.add_time = ktime_get_real_seconds();
1609         policy->curlft.use_time = 0;
1610         if (!mod_timer(&policy->timer, jiffies + HZ))
1611                 xfrm_pol_hold(policy);
1612         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1613
1614         if (delpol)
1615                 xfrm_policy_kill(delpol);
1616         else if (xfrm_bydst_should_resize(net, dir, NULL))
1617                 schedule_work(&net->xfrm.policy_hash_work);
1618
1619         return 0;
1620 }
1621 EXPORT_SYMBOL(xfrm_policy_insert);
1622
1623 static struct xfrm_policy *
1624 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1625                         u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1626                         struct xfrm_sec_ctx *ctx)
1627 {
1628         struct xfrm_policy *pol;
1629
1630         if (!chain)
1631                 return NULL;
1632
1633         hlist_for_each_entry(pol, chain, bydst) {
1634                 if (pol->type == type &&
1635                     pol->if_id == if_id &&
1636                     xfrm_policy_mark_match(mark, pol) &&
1637                     !selector_cmp(sel, &pol->selector) &&
1638                     xfrm_sec_ctx_match(ctx, pol->security))
1639                         return pol;
1640         }
1641
1642         return NULL;
1643 }
1644
1645 struct xfrm_policy *
1646 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1647                       u8 type, int dir, struct xfrm_selector *sel,
1648                       struct xfrm_sec_ctx *ctx, int delete, int *err)
1649 {
1650         struct xfrm_pol_inexact_bin *bin = NULL;
1651         struct xfrm_policy *pol, *ret = NULL;
1652         struct hlist_head *chain;
1653
1654         *err = 0;
1655         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1656         chain = policy_hash_bysel(net, sel, sel->family, dir);
1657         if (!chain) {
1658                 struct xfrm_pol_inexact_candidates cand;
1659                 int i;
1660
1661                 bin = xfrm_policy_inexact_lookup(net, type,
1662                                                  sel->family, dir, if_id);
1663                 if (!bin) {
1664                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1665                         return NULL;
1666                 }
1667
1668                 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1669                                                          &sel->saddr,
1670                                                          &sel->daddr)) {
1671                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1672                         return NULL;
1673                 }
1674
1675                 pol = NULL;
1676                 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1677                         struct xfrm_policy *tmp;
1678
1679                         tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1680                                                       if_id, type, dir,
1681                                                       sel, ctx);
1682                         if (!tmp)
1683                                 continue;
1684
1685                         if (!pol || tmp->pos < pol->pos)
1686                                 pol = tmp;
1687                 }
1688         } else {
1689                 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1690                                               sel, ctx);
1691         }
1692
1693         if (pol) {
1694                 xfrm_pol_hold(pol);
1695                 if (delete) {
1696                         *err = security_xfrm_policy_delete(pol->security);
1697                         if (*err) {
1698                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1699                                 return pol;
1700                         }
1701                         __xfrm_policy_unlink(pol, dir);
1702                 }
1703                 ret = pol;
1704         }
1705         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1706
1707         if (ret && delete)
1708                 xfrm_policy_kill(ret);
1709         if (bin && delete)
1710                 xfrm_policy_inexact_prune_bin(bin);
1711         return ret;
1712 }
1713 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1714
1715 struct xfrm_policy *
1716 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1717                  u8 type, int dir, u32 id, int delete, int *err)
1718 {
1719         struct xfrm_policy *pol, *ret;
1720         struct hlist_head *chain;
1721
1722         *err = -ENOENT;
1723         if (xfrm_policy_id2dir(id) != dir)
1724                 return NULL;
1725
1726         *err = 0;
1727         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1728         chain = net->xfrm.policy_byidx + idx_hash(net, id);
1729         ret = NULL;
1730         hlist_for_each_entry(pol, chain, byidx) {
1731                 if (pol->type == type && pol->index == id &&
1732                     pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1733                         xfrm_pol_hold(pol);
1734                         if (delete) {
1735                                 *err = security_xfrm_policy_delete(
1736                                                                 pol->security);
1737                                 if (*err) {
1738                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1739                                         return pol;
1740                                 }
1741                                 __xfrm_policy_unlink(pol, dir);
1742                         }
1743                         ret = pol;
1744                         break;
1745                 }
1746         }
1747         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1748
1749         if (ret && delete)
1750                 xfrm_policy_kill(ret);
1751         return ret;
1752 }
1753 EXPORT_SYMBOL(xfrm_policy_byid);
1754
1755 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1756 static inline int
1757 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1758 {
1759         struct xfrm_policy *pol;
1760         int err = 0;
1761
1762         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1763                 if (pol->walk.dead ||
1764                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1765                     pol->type != type)
1766                         continue;
1767
1768                 err = security_xfrm_policy_delete(pol->security);
1769                 if (err) {
1770                         xfrm_audit_policy_delete(pol, 0, task_valid);
1771                         return err;
1772                 }
1773         }
1774         return err;
1775 }
1776
1777 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1778                                                      struct net_device *dev,
1779                                                      bool task_valid)
1780 {
1781         struct xfrm_policy *pol;
1782         int err = 0;
1783
1784         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1785                 if (pol->walk.dead ||
1786                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1787                     pol->xdo.dev != dev)
1788                         continue;
1789
1790                 err = security_xfrm_policy_delete(pol->security);
1791                 if (err) {
1792                         xfrm_audit_policy_delete(pol, 0, task_valid);
1793                         return err;
1794                 }
1795         }
1796         return err;
1797 }
1798 #else
1799 static inline int
1800 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1801 {
1802         return 0;
1803 }
1804
1805 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1806                                                      struct net_device *dev,
1807                                                      bool task_valid)
1808 {
1809         return 0;
1810 }
1811 #endif
1812
1813 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1814 {
1815         int dir, err = 0, cnt = 0;
1816         struct xfrm_policy *pol;
1817
1818         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1819
1820         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1821         if (err)
1822                 goto out;
1823
1824 again:
1825         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1826                 dir = xfrm_policy_id2dir(pol->index);
1827                 if (pol->walk.dead ||
1828                     dir >= XFRM_POLICY_MAX ||
1829                     pol->type != type)
1830                         continue;
1831
1832                 __xfrm_policy_unlink(pol, dir);
1833                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1834                 cnt++;
1835                 xfrm_audit_policy_delete(pol, 1, task_valid);
1836                 xfrm_policy_kill(pol);
1837                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1838                 goto again;
1839         }
1840         if (cnt)
1841                 __xfrm_policy_inexact_flush(net);
1842         else
1843                 err = -ESRCH;
1844 out:
1845         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1846         return err;
1847 }
1848 EXPORT_SYMBOL(xfrm_policy_flush);
1849
1850 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
1851                           bool task_valid)
1852 {
1853         int dir, err = 0, cnt = 0;
1854         struct xfrm_policy *pol;
1855
1856         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1857
1858         err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
1859         if (err)
1860                 goto out;
1861
1862 again:
1863         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1864                 dir = xfrm_policy_id2dir(pol->index);
1865                 if (pol->walk.dead ||
1866                     dir >= XFRM_POLICY_MAX ||
1867                     pol->xdo.dev != dev)
1868                         continue;
1869
1870                 __xfrm_policy_unlink(pol, dir);
1871                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1872                 cnt++;
1873                 xfrm_audit_policy_delete(pol, 1, task_valid);
1874                 xfrm_policy_kill(pol);
1875                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1876                 goto again;
1877         }
1878         if (cnt)
1879                 __xfrm_policy_inexact_flush(net);
1880         else
1881                 err = -ESRCH;
1882 out:
1883         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1884         return err;
1885 }
1886 EXPORT_SYMBOL(xfrm_dev_policy_flush);
1887
1888 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1889                      int (*func)(struct xfrm_policy *, int, int, void*),
1890                      void *data)
1891 {
1892         struct xfrm_policy *pol;
1893         struct xfrm_policy_walk_entry *x;
1894         int error = 0;
1895
1896         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1897             walk->type != XFRM_POLICY_TYPE_ANY)
1898                 return -EINVAL;
1899
1900         if (list_empty(&walk->walk.all) && walk->seq != 0)
1901                 return 0;
1902
1903         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1904         if (list_empty(&walk->walk.all))
1905                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1906         else
1907                 x = list_first_entry(&walk->walk.all,
1908                                      struct xfrm_policy_walk_entry, all);
1909
1910         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1911                 if (x->dead)
1912                         continue;
1913                 pol = container_of(x, struct xfrm_policy, walk);
1914                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1915                     walk->type != pol->type)
1916                         continue;
1917                 error = func(pol, xfrm_policy_id2dir(pol->index),
1918                              walk->seq, data);
1919                 if (error) {
1920                         list_move_tail(&walk->walk.all, &x->all);
1921                         goto out;
1922                 }
1923                 walk->seq++;
1924         }
1925         if (walk->seq == 0) {
1926                 error = -ENOENT;
1927                 goto out;
1928         }
1929         list_del_init(&walk->walk.all);
1930 out:
1931         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1932         return error;
1933 }
1934 EXPORT_SYMBOL(xfrm_policy_walk);
1935
1936 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1937 {
1938         INIT_LIST_HEAD(&walk->walk.all);
1939         walk->walk.dead = 1;
1940         walk->type = type;
1941         walk->seq = 0;
1942 }
1943 EXPORT_SYMBOL(xfrm_policy_walk_init);
1944
1945 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1946 {
1947         if (list_empty(&walk->walk.all))
1948                 return;
1949
1950         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1951         list_del(&walk->walk.all);
1952         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1953 }
1954 EXPORT_SYMBOL(xfrm_policy_walk_done);
1955
1956 /*
1957  * Find policy to apply to this flow.
1958  *
1959  * Returns 0 if policy found, else an -errno.
1960  */
1961 static int xfrm_policy_match(const struct xfrm_policy *pol,
1962                              const struct flowi *fl,
1963                              u8 type, u16 family, u32 if_id)
1964 {
1965         const struct xfrm_selector *sel = &pol->selector;
1966         int ret = -ESRCH;
1967         bool match;
1968
1969         if (pol->family != family ||
1970             pol->if_id != if_id ||
1971             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1972             pol->type != type)
1973                 return ret;
1974
1975         match = xfrm_selector_match(sel, fl, family);
1976         if (match)
1977                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
1978         return ret;
1979 }
1980
1981 static struct xfrm_pol_inexact_node *
1982 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1983                                 seqcount_spinlock_t *count,
1984                                 const xfrm_address_t *addr, u16 family)
1985 {
1986         const struct rb_node *parent;
1987         int seq;
1988
1989 again:
1990         seq = read_seqcount_begin(count);
1991
1992         parent = rcu_dereference_raw(r->rb_node);
1993         while (parent) {
1994                 struct xfrm_pol_inexact_node *node;
1995                 int delta;
1996
1997                 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
1998
1999                 delta = xfrm_policy_addr_delta(addr, &node->addr,
2000                                                node->prefixlen, family);
2001                 if (delta < 0) {
2002                         parent = rcu_dereference_raw(parent->rb_left);
2003                         continue;
2004                 } else if (delta > 0) {
2005                         parent = rcu_dereference_raw(parent->rb_right);
2006                         continue;
2007                 }
2008
2009                 return node;
2010         }
2011
2012         if (read_seqcount_retry(count, seq))
2013                 goto again;
2014
2015         return NULL;
2016 }
2017
2018 static bool
2019 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
2020                                     struct xfrm_pol_inexact_bin *b,
2021                                     const xfrm_address_t *saddr,
2022                                     const xfrm_address_t *daddr)
2023 {
2024         struct xfrm_pol_inexact_node *n;
2025         u16 family;
2026
2027         if (!b)
2028                 return false;
2029
2030         family = b->k.family;
2031         memset(cand, 0, sizeof(*cand));
2032         cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
2033
2034         n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
2035                                             family);
2036         if (n) {
2037                 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
2038                 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
2039                                                     family);
2040                 if (n)
2041                         cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
2042         }
2043
2044         n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
2045                                             family);
2046         if (n)
2047                 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
2048
2049         return true;
2050 }
2051
2052 static struct xfrm_pol_inexact_bin *
2053 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
2054                                u8 dir, u32 if_id)
2055 {
2056         struct xfrm_pol_inexact_key k = {
2057                 .family = family,
2058                 .type = type,
2059                 .dir = dir,
2060                 .if_id = if_id,
2061         };
2062
2063         write_pnet(&k.net, net);
2064
2065         return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
2066                                  xfrm_pol_inexact_params);
2067 }
2068
2069 static struct xfrm_pol_inexact_bin *
2070 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2071                            u8 dir, u32 if_id)
2072 {
2073         struct xfrm_pol_inexact_bin *bin;
2074
2075         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2076
2077         rcu_read_lock();
2078         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2079         rcu_read_unlock();
2080
2081         return bin;
2082 }
2083
2084 static struct xfrm_policy *
2085 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2086                               struct xfrm_policy *prefer,
2087                               const struct flowi *fl,
2088                               u8 type, u16 family, u32 if_id)
2089 {
2090         u32 priority = prefer ? prefer->priority : ~0u;
2091         struct xfrm_policy *pol;
2092
2093         if (!chain)
2094                 return NULL;
2095
2096         hlist_for_each_entry_rcu(pol, chain, bydst) {
2097                 int err;
2098
2099                 if (pol->priority > priority)
2100                         break;
2101
2102                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2103                 if (err) {
2104                         if (err != -ESRCH)
2105                                 return ERR_PTR(err);
2106
2107                         continue;
2108                 }
2109
2110                 if (prefer) {
2111                         /* matches.  Is it older than *prefer? */
2112                         if (pol->priority == priority &&
2113                             prefer->pos < pol->pos)
2114                                 return prefer;
2115                 }
2116
2117                 return pol;
2118         }
2119
2120         return NULL;
2121 }
2122
2123 static struct xfrm_policy *
2124 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2125                             struct xfrm_policy *prefer,
2126                             const struct flowi *fl,
2127                             u8 type, u16 family, u32 if_id)
2128 {
2129         struct xfrm_policy *tmp;
2130         int i;
2131
2132         for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2133                 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2134                                                     prefer,
2135                                                     fl, type, family, if_id);
2136                 if (!tmp)
2137                         continue;
2138
2139                 if (IS_ERR(tmp))
2140                         return tmp;
2141                 prefer = tmp;
2142         }
2143
2144         return prefer;
2145 }
2146
2147 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2148                                                      const struct flowi *fl,
2149                                                      u16 family, u8 dir,
2150                                                      u32 if_id)
2151 {
2152         struct xfrm_pol_inexact_candidates cand;
2153         const xfrm_address_t *daddr, *saddr;
2154         struct xfrm_pol_inexact_bin *bin;
2155         struct xfrm_policy *pol, *ret;
2156         struct hlist_head *chain;
2157         unsigned int sequence;
2158         int err;
2159
2160         daddr = xfrm_flowi_daddr(fl, family);
2161         saddr = xfrm_flowi_saddr(fl, family);
2162         if (unlikely(!daddr || !saddr))
2163                 return NULL;
2164
2165         rcu_read_lock();
2166  retry:
2167         do {
2168                 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2169                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2170         } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2171
2172         ret = NULL;
2173         hlist_for_each_entry_rcu(pol, chain, bydst) {
2174                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2175                 if (err) {
2176                         if (err == -ESRCH)
2177                                 continue;
2178                         else {
2179                                 ret = ERR_PTR(err);
2180                                 goto fail;
2181                         }
2182                 } else {
2183                         ret = pol;
2184                         break;
2185                 }
2186         }
2187         if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
2188                 goto skip_inexact;
2189
2190         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2191         if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2192                                                          daddr))
2193                 goto skip_inexact;
2194
2195         pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2196                                           family, if_id);
2197         if (pol) {
2198                 ret = pol;
2199                 if (IS_ERR(pol))
2200                         goto fail;
2201         }
2202
2203 skip_inexact:
2204         if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2205                 goto retry;
2206
2207         if (ret && !xfrm_pol_hold_rcu(ret))
2208                 goto retry;
2209 fail:
2210         rcu_read_unlock();
2211
2212         return ret;
2213 }
2214
2215 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2216                                               const struct flowi *fl,
2217                                               u16 family, u8 dir, u32 if_id)
2218 {
2219 #ifdef CONFIG_XFRM_SUB_POLICY
2220         struct xfrm_policy *pol;
2221
2222         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2223                                         dir, if_id);
2224         if (pol != NULL)
2225                 return pol;
2226 #endif
2227         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2228                                          dir, if_id);
2229 }
2230
2231 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2232                                                  const struct flowi *fl,
2233                                                  u16 family, u32 if_id)
2234 {
2235         struct xfrm_policy *pol;
2236
2237         rcu_read_lock();
2238  again:
2239         pol = rcu_dereference(sk->sk_policy[dir]);
2240         if (pol != NULL) {
2241                 bool match;
2242                 int err = 0;
2243
2244                 if (pol->family != family) {
2245                         pol = NULL;
2246                         goto out;
2247                 }
2248
2249                 match = xfrm_selector_match(&pol->selector, fl, family);
2250                 if (match) {
2251                         if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
2252                             pol->if_id != if_id) {
2253                                 pol = NULL;
2254                                 goto out;
2255                         }
2256                         err = security_xfrm_policy_lookup(pol->security,
2257                                                       fl->flowi_secid);
2258                         if (!err) {
2259                                 if (!xfrm_pol_hold_rcu(pol))
2260                                         goto again;
2261                         } else if (err == -ESRCH) {
2262                                 pol = NULL;
2263                         } else {
2264                                 pol = ERR_PTR(err);
2265                         }
2266                 } else
2267                         pol = NULL;
2268         }
2269 out:
2270         rcu_read_unlock();
2271         return pol;
2272 }
2273
2274 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2275 {
2276         struct net *net = xp_net(pol);
2277
2278         list_add(&pol->walk.all, &net->xfrm.policy_all);
2279         net->xfrm.policy_count[dir]++;
2280         xfrm_pol_hold(pol);
2281 }
2282
2283 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2284                                                 int dir)
2285 {
2286         struct net *net = xp_net(pol);
2287
2288         if (list_empty(&pol->walk.all))
2289                 return NULL;
2290
2291         /* Socket policies are not hashed. */
2292         if (!hlist_unhashed(&pol->bydst)) {
2293                 hlist_del_rcu(&pol->bydst);
2294                 hlist_del_init(&pol->bydst_inexact_list);
2295                 hlist_del(&pol->byidx);
2296         }
2297
2298         list_del_init(&pol->walk.all);
2299         net->xfrm.policy_count[dir]--;
2300
2301         return pol;
2302 }
2303
2304 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2305 {
2306         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2307 }
2308
2309 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2310 {
2311         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2312 }
2313
2314 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2315 {
2316         struct net *net = xp_net(pol);
2317
2318         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2319         pol = __xfrm_policy_unlink(pol, dir);
2320         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2321         if (pol) {
2322                 xfrm_dev_policy_delete(pol);
2323                 xfrm_policy_kill(pol);
2324                 return 0;
2325         }
2326         return -ENOENT;
2327 }
2328 EXPORT_SYMBOL(xfrm_policy_delete);
2329
2330 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2331 {
2332         struct net *net = sock_net(sk);
2333         struct xfrm_policy *old_pol;
2334
2335 #ifdef CONFIG_XFRM_SUB_POLICY
2336         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2337                 return -EINVAL;
2338 #endif
2339
2340         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2341         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2342                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2343         if (pol) {
2344                 pol->curlft.add_time = ktime_get_real_seconds();
2345                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2346                 xfrm_sk_policy_link(pol, dir);
2347         }
2348         rcu_assign_pointer(sk->sk_policy[dir], pol);
2349         if (old_pol) {
2350                 if (pol)
2351                         xfrm_policy_requeue(old_pol, pol);
2352
2353                 /* Unlinking succeeds always. This is the only function
2354                  * allowed to delete or replace socket policy.
2355                  */
2356                 xfrm_sk_policy_unlink(old_pol, dir);
2357         }
2358         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2359
2360         if (old_pol) {
2361                 xfrm_policy_kill(old_pol);
2362         }
2363         return 0;
2364 }
2365
2366 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2367 {
2368         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2369         struct net *net = xp_net(old);
2370
2371         if (newp) {
2372                 newp->selector = old->selector;
2373                 if (security_xfrm_policy_clone(old->security,
2374                                                &newp->security)) {
2375                         kfree(newp);
2376                         return NULL;  /* ENOMEM */
2377                 }
2378                 newp->lft = old->lft;
2379                 newp->curlft = old->curlft;
2380                 newp->mark = old->mark;
2381                 newp->if_id = old->if_id;
2382                 newp->action = old->action;
2383                 newp->flags = old->flags;
2384                 newp->xfrm_nr = old->xfrm_nr;
2385                 newp->index = old->index;
2386                 newp->type = old->type;
2387                 newp->family = old->family;
2388                 memcpy(newp->xfrm_vec, old->xfrm_vec,
2389                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2390                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2391                 xfrm_sk_policy_link(newp, dir);
2392                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2393                 xfrm_pol_put(newp);
2394         }
2395         return newp;
2396 }
2397
2398 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2399 {
2400         const struct xfrm_policy *p;
2401         struct xfrm_policy *np;
2402         int i, ret = 0;
2403
2404         rcu_read_lock();
2405         for (i = 0; i < 2; i++) {
2406                 p = rcu_dereference(osk->sk_policy[i]);
2407                 if (p) {
2408                         np = clone_policy(p, i);
2409                         if (unlikely(!np)) {
2410                                 ret = -ENOMEM;
2411                                 break;
2412                         }
2413                         rcu_assign_pointer(sk->sk_policy[i], np);
2414                 }
2415         }
2416         rcu_read_unlock();
2417         return ret;
2418 }
2419
2420 static int
2421 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2422                xfrm_address_t *remote, unsigned short family, u32 mark)
2423 {
2424         int err;
2425         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2426
2427         if (unlikely(afinfo == NULL))
2428                 return -EINVAL;
2429         err = afinfo->get_saddr(net, oif, local, remote, mark);
2430         rcu_read_unlock();
2431         return err;
2432 }
2433
2434 /* Resolve list of templates for the flow, given policy. */
2435
2436 static int
2437 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2438                       struct xfrm_state **xfrm, unsigned short family)
2439 {
2440         struct net *net = xp_net(policy);
2441         int nx;
2442         int i, error;
2443         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2444         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2445         xfrm_address_t tmp;
2446
2447         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2448                 struct xfrm_state *x;
2449                 xfrm_address_t *remote = daddr;
2450                 xfrm_address_t *local  = saddr;
2451                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2452
2453                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2454                     tmpl->mode == XFRM_MODE_BEET) {
2455                         remote = &tmpl->id.daddr;
2456                         local = &tmpl->saddr;
2457                         if (xfrm_addr_any(local, tmpl->encap_family)) {
2458                                 error = xfrm_get_saddr(net, fl->flowi_oif,
2459                                                        &tmp, remote,
2460                                                        tmpl->encap_family, 0);
2461                                 if (error)
2462                                         goto fail;
2463                                 local = &tmp;
2464                         }
2465                 }
2466
2467                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2468                                     family, policy->if_id);
2469
2470                 if (x && x->km.state == XFRM_STATE_VALID) {
2471                         xfrm[nx++] = x;
2472                         daddr = remote;
2473                         saddr = local;
2474                         continue;
2475                 }
2476                 if (x) {
2477                         error = (x->km.state == XFRM_STATE_ERROR ?
2478                                  -EINVAL : -EAGAIN);
2479                         xfrm_state_put(x);
2480                 } else if (error == -ESRCH) {
2481                         error = -EAGAIN;
2482                 }
2483
2484                 if (!tmpl->optional)
2485                         goto fail;
2486         }
2487         return nx;
2488
2489 fail:
2490         for (nx--; nx >= 0; nx--)
2491                 xfrm_state_put(xfrm[nx]);
2492         return error;
2493 }
2494
2495 static int
2496 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2497                   struct xfrm_state **xfrm, unsigned short family)
2498 {
2499         struct xfrm_state *tp[XFRM_MAX_DEPTH];
2500         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2501         int cnx = 0;
2502         int error;
2503         int ret;
2504         int i;
2505
2506         for (i = 0; i < npols; i++) {
2507                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2508                         error = -ENOBUFS;
2509                         goto fail;
2510                 }
2511
2512                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2513                 if (ret < 0) {
2514                         error = ret;
2515                         goto fail;
2516                 } else
2517                         cnx += ret;
2518         }
2519
2520         /* found states are sorted for outbound processing */
2521         if (npols > 1)
2522                 xfrm_state_sort(xfrm, tpp, cnx, family);
2523
2524         return cnx;
2525
2526  fail:
2527         for (cnx--; cnx >= 0; cnx--)
2528                 xfrm_state_put(tpp[cnx]);
2529         return error;
2530
2531 }
2532
2533 static int xfrm_get_tos(const struct flowi *fl, int family)
2534 {
2535         if (family == AF_INET)
2536                 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2537
2538         return 0;
2539 }
2540
2541 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2542 {
2543         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2544         struct dst_ops *dst_ops;
2545         struct xfrm_dst *xdst;
2546
2547         if (!afinfo)
2548                 return ERR_PTR(-EINVAL);
2549
2550         switch (family) {
2551         case AF_INET:
2552                 dst_ops = &net->xfrm.xfrm4_dst_ops;
2553                 break;
2554 #if IS_ENABLED(CONFIG_IPV6)
2555         case AF_INET6:
2556                 dst_ops = &net->xfrm.xfrm6_dst_ops;
2557                 break;
2558 #endif
2559         default:
2560                 BUG();
2561         }
2562         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2563
2564         if (likely(xdst)) {
2565                 memset_after(xdst, 0, u.dst);
2566         } else
2567                 xdst = ERR_PTR(-ENOBUFS);
2568
2569         rcu_read_unlock();
2570
2571         return xdst;
2572 }
2573
2574 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2575                            int nfheader_len)
2576 {
2577         if (dst->ops->family == AF_INET6) {
2578                 struct rt6_info *rt = (struct rt6_info *)dst;
2579                 path->path_cookie = rt6_get_cookie(rt);
2580                 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2581         }
2582 }
2583
2584 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2585                                 const struct flowi *fl)
2586 {
2587         const struct xfrm_policy_afinfo *afinfo =
2588                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2589         int err;
2590
2591         if (!afinfo)
2592                 return -EINVAL;
2593
2594         err = afinfo->fill_dst(xdst, dev, fl);
2595
2596         rcu_read_unlock();
2597
2598         return err;
2599 }
2600
2601
2602 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2603  * all the metrics... Shortly, bundle a bundle.
2604  */
2605
2606 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2607                                             struct xfrm_state **xfrm,
2608                                             struct xfrm_dst **bundle,
2609                                             int nx,
2610                                             const struct flowi *fl,
2611                                             struct dst_entry *dst)
2612 {
2613         const struct xfrm_state_afinfo *afinfo;
2614         const struct xfrm_mode *inner_mode;
2615         struct net *net = xp_net(policy);
2616         unsigned long now = jiffies;
2617         struct net_device *dev;
2618         struct xfrm_dst *xdst_prev = NULL;
2619         struct xfrm_dst *xdst0 = NULL;
2620         int i = 0;
2621         int err;
2622         int header_len = 0;
2623         int nfheader_len = 0;
2624         int trailer_len = 0;
2625         int tos;
2626         int family = policy->selector.family;
2627         xfrm_address_t saddr, daddr;
2628
2629         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2630
2631         tos = xfrm_get_tos(fl, family);
2632
2633         dst_hold(dst);
2634
2635         for (; i < nx; i++) {
2636                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2637                 struct dst_entry *dst1 = &xdst->u.dst;
2638
2639                 err = PTR_ERR(xdst);
2640                 if (IS_ERR(xdst)) {
2641                         dst_release(dst);
2642                         goto put_states;
2643                 }
2644
2645                 bundle[i] = xdst;
2646                 if (!xdst_prev)
2647                         xdst0 = xdst;
2648                 else
2649                         /* Ref count is taken during xfrm_alloc_dst()
2650                          * No need to do dst_clone() on dst1
2651                          */
2652                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2653
2654                 if (xfrm[i]->sel.family == AF_UNSPEC) {
2655                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
2656                                                         xfrm_af2proto(family));
2657                         if (!inner_mode) {
2658                                 err = -EAFNOSUPPORT;
2659                                 dst_release(dst);
2660                                 goto put_states;
2661                         }
2662                 } else
2663                         inner_mode = &xfrm[i]->inner_mode;
2664
2665                 xdst->route = dst;
2666                 dst_copy_metrics(dst1, dst);
2667
2668                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2669                         __u32 mark = 0;
2670                         int oif;
2671
2672                         if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2673                                 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2674
2675                         family = xfrm[i]->props.family;
2676                         oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2677                         dst = xfrm_dst_lookup(xfrm[i], tos, oif,
2678                                               &saddr, &daddr, family, mark);
2679                         err = PTR_ERR(dst);
2680                         if (IS_ERR(dst))
2681                                 goto put_states;
2682                 } else
2683                         dst_hold(dst);
2684
2685                 dst1->xfrm = xfrm[i];
2686                 xdst->xfrm_genid = xfrm[i]->genid;
2687
2688                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2689                 dst1->lastuse = now;
2690
2691                 dst1->input = dst_discard;
2692
2693                 rcu_read_lock();
2694                 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2695                 if (likely(afinfo))
2696                         dst1->output = afinfo->output;
2697                 else
2698                         dst1->output = dst_discard_out;
2699                 rcu_read_unlock();
2700
2701                 xdst_prev = xdst;
2702
2703                 header_len += xfrm[i]->props.header_len;
2704                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2705                         nfheader_len += xfrm[i]->props.header_len;
2706                 trailer_len += xfrm[i]->props.trailer_len;
2707         }
2708
2709         xfrm_dst_set_child(xdst_prev, dst);
2710         xdst0->path = dst;
2711
2712         err = -ENODEV;
2713         dev = dst->dev;
2714         if (!dev)
2715                 goto free_dst;
2716
2717         xfrm_init_path(xdst0, dst, nfheader_len);
2718         xfrm_init_pmtu(bundle, nx);
2719
2720         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2721              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2722                 err = xfrm_fill_dst(xdst_prev, dev, fl);
2723                 if (err)
2724                         goto free_dst;
2725
2726                 xdst_prev->u.dst.header_len = header_len;
2727                 xdst_prev->u.dst.trailer_len = trailer_len;
2728                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2729                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2730         }
2731
2732         return &xdst0->u.dst;
2733
2734 put_states:
2735         for (; i < nx; i++)
2736                 xfrm_state_put(xfrm[i]);
2737 free_dst:
2738         if (xdst0)
2739                 dst_release_immediate(&xdst0->u.dst);
2740
2741         return ERR_PTR(err);
2742 }
2743
2744 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2745                                 struct xfrm_policy **pols,
2746                                 int *num_pols, int *num_xfrms)
2747 {
2748         int i;
2749
2750         if (*num_pols == 0 || !pols[0]) {
2751                 *num_pols = 0;
2752                 *num_xfrms = 0;
2753                 return 0;
2754         }
2755         if (IS_ERR(pols[0])) {
2756                 *num_pols = 0;
2757                 return PTR_ERR(pols[0]);
2758         }
2759
2760         *num_xfrms = pols[0]->xfrm_nr;
2761
2762 #ifdef CONFIG_XFRM_SUB_POLICY
2763         if (pols[0]->action == XFRM_POLICY_ALLOW &&
2764             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2765                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2766                                                     XFRM_POLICY_TYPE_MAIN,
2767                                                     fl, family,
2768                                                     XFRM_POLICY_OUT,
2769                                                     pols[0]->if_id);
2770                 if (pols[1]) {
2771                         if (IS_ERR(pols[1])) {
2772                                 xfrm_pols_put(pols, *num_pols);
2773                                 *num_pols = 0;
2774                                 return PTR_ERR(pols[1]);
2775                         }
2776                         (*num_pols)++;
2777                         (*num_xfrms) += pols[1]->xfrm_nr;
2778                 }
2779         }
2780 #endif
2781         for (i = 0; i < *num_pols; i++) {
2782                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2783                         *num_xfrms = -1;
2784                         break;
2785                 }
2786         }
2787
2788         return 0;
2789
2790 }
2791
2792 static struct xfrm_dst *
2793 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2794                                const struct flowi *fl, u16 family,
2795                                struct dst_entry *dst_orig)
2796 {
2797         struct net *net = xp_net(pols[0]);
2798         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2799         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2800         struct xfrm_dst *xdst;
2801         struct dst_entry *dst;
2802         int err;
2803
2804         /* Try to instantiate a bundle */
2805         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2806         if (err <= 0) {
2807                 if (err == 0)
2808                         return NULL;
2809
2810                 if (err != -EAGAIN)
2811                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2812                 return ERR_PTR(err);
2813         }
2814
2815         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2816         if (IS_ERR(dst)) {
2817                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2818                 return ERR_CAST(dst);
2819         }
2820
2821         xdst = (struct xfrm_dst *)dst;
2822         xdst->num_xfrms = err;
2823         xdst->num_pols = num_pols;
2824         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2825         xdst->policy_genid = atomic_read(&pols[0]->genid);
2826
2827         return xdst;
2828 }
2829
2830 static void xfrm_policy_queue_process(struct timer_list *t)
2831 {
2832         struct sk_buff *skb;
2833         struct sock *sk;
2834         struct dst_entry *dst;
2835         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2836         struct net *net = xp_net(pol);
2837         struct xfrm_policy_queue *pq = &pol->polq;
2838         struct flowi fl;
2839         struct sk_buff_head list;
2840         __u32 skb_mark;
2841
2842         spin_lock(&pq->hold_queue.lock);
2843         skb = skb_peek(&pq->hold_queue);
2844         if (!skb) {
2845                 spin_unlock(&pq->hold_queue.lock);
2846                 goto out;
2847         }
2848         dst = skb_dst(skb);
2849         sk = skb->sk;
2850
2851         /* Fixup the mark to support VTI. */
2852         skb_mark = skb->mark;
2853         skb->mark = pol->mark.v;
2854         xfrm_decode_session(skb, &fl, dst->ops->family);
2855         skb->mark = skb_mark;
2856         spin_unlock(&pq->hold_queue.lock);
2857
2858         dst_hold(xfrm_dst_path(dst));
2859         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2860         if (IS_ERR(dst))
2861                 goto purge_queue;
2862
2863         if (dst->flags & DST_XFRM_QUEUE) {
2864                 dst_release(dst);
2865
2866                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2867                         goto purge_queue;
2868
2869                 pq->timeout = pq->timeout << 1;
2870                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2871                         xfrm_pol_hold(pol);
2872                 goto out;
2873         }
2874
2875         dst_release(dst);
2876
2877         __skb_queue_head_init(&list);
2878
2879         spin_lock(&pq->hold_queue.lock);
2880         pq->timeout = 0;
2881         skb_queue_splice_init(&pq->hold_queue, &list);
2882         spin_unlock(&pq->hold_queue.lock);
2883
2884         while (!skb_queue_empty(&list)) {
2885                 skb = __skb_dequeue(&list);
2886
2887                 /* Fixup the mark to support VTI. */
2888                 skb_mark = skb->mark;
2889                 skb->mark = pol->mark.v;
2890                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2891                 skb->mark = skb_mark;
2892
2893                 dst_hold(xfrm_dst_path(skb_dst(skb)));
2894                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2895                 if (IS_ERR(dst)) {
2896                         kfree_skb(skb);
2897                         continue;
2898                 }
2899
2900                 nf_reset_ct(skb);
2901                 skb_dst_drop(skb);
2902                 skb_dst_set(skb, dst);
2903
2904                 dst_output(net, skb->sk, skb);
2905         }
2906
2907 out:
2908         xfrm_pol_put(pol);
2909         return;
2910
2911 purge_queue:
2912         pq->timeout = 0;
2913         skb_queue_purge(&pq->hold_queue);
2914         xfrm_pol_put(pol);
2915 }
2916
2917 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2918 {
2919         unsigned long sched_next;
2920         struct dst_entry *dst = skb_dst(skb);
2921         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2922         struct xfrm_policy *pol = xdst->pols[0];
2923         struct xfrm_policy_queue *pq = &pol->polq;
2924
2925         if (unlikely(skb_fclone_busy(sk, skb))) {
2926                 kfree_skb(skb);
2927                 return 0;
2928         }
2929
2930         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2931                 kfree_skb(skb);
2932                 return -EAGAIN;
2933         }
2934
2935         skb_dst_force(skb);
2936
2937         spin_lock_bh(&pq->hold_queue.lock);
2938
2939         if (!pq->timeout)
2940                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2941
2942         sched_next = jiffies + pq->timeout;
2943
2944         if (del_timer(&pq->hold_timer)) {
2945                 if (time_before(pq->hold_timer.expires, sched_next))
2946                         sched_next = pq->hold_timer.expires;
2947                 xfrm_pol_put(pol);
2948         }
2949
2950         __skb_queue_tail(&pq->hold_queue, skb);
2951         if (!mod_timer(&pq->hold_timer, sched_next))
2952                 xfrm_pol_hold(pol);
2953
2954         spin_unlock_bh(&pq->hold_queue.lock);
2955
2956         return 0;
2957 }
2958
2959 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2960                                                  struct xfrm_flo *xflo,
2961                                                  const struct flowi *fl,
2962                                                  int num_xfrms,
2963                                                  u16 family)
2964 {
2965         int err;
2966         struct net_device *dev;
2967         struct dst_entry *dst;
2968         struct dst_entry *dst1;
2969         struct xfrm_dst *xdst;
2970
2971         xdst = xfrm_alloc_dst(net, family);
2972         if (IS_ERR(xdst))
2973                 return xdst;
2974
2975         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2976             net->xfrm.sysctl_larval_drop ||
2977             num_xfrms <= 0)
2978                 return xdst;
2979
2980         dst = xflo->dst_orig;
2981         dst1 = &xdst->u.dst;
2982         dst_hold(dst);
2983         xdst->route = dst;
2984
2985         dst_copy_metrics(dst1, dst);
2986
2987         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2988         dst1->flags |= DST_XFRM_QUEUE;
2989         dst1->lastuse = jiffies;
2990
2991         dst1->input = dst_discard;
2992         dst1->output = xdst_queue_output;
2993
2994         dst_hold(dst);
2995         xfrm_dst_set_child(xdst, dst);
2996         xdst->path = dst;
2997
2998         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2999
3000         err = -ENODEV;
3001         dev = dst->dev;
3002         if (!dev)
3003                 goto free_dst;
3004
3005         err = xfrm_fill_dst(xdst, dev, fl);
3006         if (err)
3007                 goto free_dst;
3008
3009 out:
3010         return xdst;
3011
3012 free_dst:
3013         dst_release(dst1);
3014         xdst = ERR_PTR(err);
3015         goto out;
3016 }
3017
3018 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
3019                                            const struct flowi *fl,
3020                                            u16 family, u8 dir,
3021                                            struct xfrm_flo *xflo, u32 if_id)
3022 {
3023         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3024         int num_pols = 0, num_xfrms = 0, err;
3025         struct xfrm_dst *xdst;
3026
3027         /* Resolve policies to use if we couldn't get them from
3028          * previous cache entry */
3029         num_pols = 1;
3030         pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
3031         err = xfrm_expand_policies(fl, family, pols,
3032                                            &num_pols, &num_xfrms);
3033         if (err < 0)
3034                 goto inc_error;
3035         if (num_pols == 0)
3036                 return NULL;
3037         if (num_xfrms <= 0)
3038                 goto make_dummy_bundle;
3039
3040         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
3041                                               xflo->dst_orig);
3042         if (IS_ERR(xdst)) {
3043                 err = PTR_ERR(xdst);
3044                 if (err == -EREMOTE) {
3045                         xfrm_pols_put(pols, num_pols);
3046                         return NULL;
3047                 }
3048
3049                 if (err != -EAGAIN)
3050                         goto error;
3051                 goto make_dummy_bundle;
3052         } else if (xdst == NULL) {
3053                 num_xfrms = 0;
3054                 goto make_dummy_bundle;
3055         }
3056
3057         return xdst;
3058
3059 make_dummy_bundle:
3060         /* We found policies, but there's no bundles to instantiate:
3061          * either because the policy blocks, has no transformations or
3062          * we could not build template (no xfrm_states).*/
3063         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
3064         if (IS_ERR(xdst)) {
3065                 xfrm_pols_put(pols, num_pols);
3066                 return ERR_CAST(xdst);
3067         }
3068         xdst->num_pols = num_pols;
3069         xdst->num_xfrms = num_xfrms;
3070         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
3071
3072         return xdst;
3073
3074 inc_error:
3075         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3076 error:
3077         xfrm_pols_put(pols, num_pols);
3078         return ERR_PTR(err);
3079 }
3080
3081 static struct dst_entry *make_blackhole(struct net *net, u16 family,
3082                                         struct dst_entry *dst_orig)
3083 {
3084         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3085         struct dst_entry *ret;
3086
3087         if (!afinfo) {
3088                 dst_release(dst_orig);
3089                 return ERR_PTR(-EINVAL);
3090         } else {
3091                 ret = afinfo->blackhole_route(net, dst_orig);
3092         }
3093         rcu_read_unlock();
3094
3095         return ret;
3096 }
3097
3098 /* Finds/creates a bundle for given flow and if_id
3099  *
3100  * At the moment we eat a raw IP route. Mostly to speed up lookups
3101  * on interfaces with disabled IPsec.
3102  *
3103  * xfrm_lookup uses an if_id of 0 by default, and is provided for
3104  * compatibility
3105  */
3106 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3107                                         struct dst_entry *dst_orig,
3108                                         const struct flowi *fl,
3109                                         const struct sock *sk,
3110                                         int flags, u32 if_id)
3111 {
3112         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3113         struct xfrm_dst *xdst;
3114         struct dst_entry *dst, *route;
3115         u16 family = dst_orig->ops->family;
3116         u8 dir = XFRM_POLICY_OUT;
3117         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3118
3119         dst = NULL;
3120         xdst = NULL;
3121         route = NULL;
3122
3123         sk = sk_const_to_full_sk(sk);
3124         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3125                 num_pols = 1;
3126                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3127                                                 if_id);
3128                 err = xfrm_expand_policies(fl, family, pols,
3129                                            &num_pols, &num_xfrms);
3130                 if (err < 0)
3131                         goto dropdst;
3132
3133                 if (num_pols) {
3134                         if (num_xfrms <= 0) {
3135                                 drop_pols = num_pols;
3136                                 goto no_transform;
3137                         }
3138
3139                         xdst = xfrm_resolve_and_create_bundle(
3140                                         pols, num_pols, fl,
3141                                         family, dst_orig);
3142
3143                         if (IS_ERR(xdst)) {
3144                                 xfrm_pols_put(pols, num_pols);
3145                                 err = PTR_ERR(xdst);
3146                                 if (err == -EREMOTE)
3147                                         goto nopol;
3148
3149                                 goto dropdst;
3150                         } else if (xdst == NULL) {
3151                                 num_xfrms = 0;
3152                                 drop_pols = num_pols;
3153                                 goto no_transform;
3154                         }
3155
3156                         route = xdst->route;
3157                 }
3158         }
3159
3160         if (xdst == NULL) {
3161                 struct xfrm_flo xflo;
3162
3163                 xflo.dst_orig = dst_orig;
3164                 xflo.flags = flags;
3165
3166                 /* To accelerate a bit...  */
3167                 if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3168                                !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3169                         goto nopol;
3170
3171                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3172                 if (xdst == NULL)
3173                         goto nopol;
3174                 if (IS_ERR(xdst)) {
3175                         err = PTR_ERR(xdst);
3176                         goto dropdst;
3177                 }
3178
3179                 num_pols = xdst->num_pols;
3180                 num_xfrms = xdst->num_xfrms;
3181                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3182                 route = xdst->route;
3183         }
3184
3185         dst = &xdst->u.dst;
3186         if (route == NULL && num_xfrms > 0) {
3187                 /* The only case when xfrm_bundle_lookup() returns a
3188                  * bundle with null route, is when the template could
3189                  * not be resolved. It means policies are there, but
3190                  * bundle could not be created, since we don't yet
3191                  * have the xfrm_state's. We need to wait for KM to
3192                  * negotiate new SA's or bail out with error.*/
3193                 if (net->xfrm.sysctl_larval_drop) {
3194                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3195                         err = -EREMOTE;
3196                         goto error;
3197                 }
3198
3199                 err = -EAGAIN;
3200
3201                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3202                 goto error;
3203         }
3204
3205 no_transform:
3206         if (num_pols == 0)
3207                 goto nopol;
3208
3209         if ((flags & XFRM_LOOKUP_ICMP) &&
3210             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3211                 err = -ENOENT;
3212                 goto error;
3213         }
3214
3215         for (i = 0; i < num_pols; i++)
3216                 pols[i]->curlft.use_time = ktime_get_real_seconds();
3217
3218         if (num_xfrms < 0) {
3219                 /* Prohibit the flow */
3220                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3221                 err = -EPERM;
3222                 goto error;
3223         } else if (num_xfrms > 0) {
3224                 /* Flow transformed */
3225                 dst_release(dst_orig);
3226         } else {
3227                 /* Flow passes untransformed */
3228                 dst_release(dst);
3229                 dst = dst_orig;
3230         }
3231 ok:
3232         xfrm_pols_put(pols, drop_pols);
3233         if (dst && dst->xfrm &&
3234             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3235                 dst->flags |= DST_XFRM_TUNNEL;
3236         return dst;
3237
3238 nopol:
3239         if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3240             net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3241                 err = -EPERM;
3242                 goto error;
3243         }
3244         if (!(flags & XFRM_LOOKUP_ICMP)) {
3245                 dst = dst_orig;
3246                 goto ok;
3247         }
3248         err = -ENOENT;
3249 error:
3250         dst_release(dst);
3251 dropdst:
3252         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3253                 dst_release(dst_orig);
3254         xfrm_pols_put(pols, drop_pols);
3255         return ERR_PTR(err);
3256 }
3257 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3258
3259 /* Main function: finds/creates a bundle for given flow.
3260  *
3261  * At the moment we eat a raw IP route. Mostly to speed up lookups
3262  * on interfaces with disabled IPsec.
3263  */
3264 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3265                               const struct flowi *fl, const struct sock *sk,
3266                               int flags)
3267 {
3268         return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3269 }
3270 EXPORT_SYMBOL(xfrm_lookup);
3271
3272 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3273  * Otherwise we may send out blackholed packets.
3274  */
3275 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3276                                     const struct flowi *fl,
3277                                     const struct sock *sk, int flags)
3278 {
3279         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3280                                             flags | XFRM_LOOKUP_QUEUE |
3281                                             XFRM_LOOKUP_KEEP_DST_REF);
3282
3283         if (PTR_ERR(dst) == -EREMOTE)
3284                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3285
3286         if (IS_ERR(dst))
3287                 dst_release(dst_orig);
3288
3289         return dst;
3290 }
3291 EXPORT_SYMBOL(xfrm_lookup_route);
3292
3293 static inline int
3294 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3295 {
3296         struct sec_path *sp = skb_sec_path(skb);
3297         struct xfrm_state *x;
3298
3299         if (!sp || idx < 0 || idx >= sp->len)
3300                 return 0;
3301         x = sp->xvec[idx];
3302         if (!x->type->reject)
3303                 return 0;
3304         return x->type->reject(x, skb, fl);
3305 }
3306
3307 /* When skb is transformed back to its "native" form, we have to
3308  * check policy restrictions. At the moment we make this in maximally
3309  * stupid way. Shame on me. :-) Of course, connected sockets must
3310  * have policy cached at them.
3311  */
3312
3313 static inline int
3314 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3315               unsigned short family, u32 if_id)
3316 {
3317         if (xfrm_state_kern(x))
3318                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3319         return  x->id.proto == tmpl->id.proto &&
3320                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3321                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3322                 x->props.mode == tmpl->mode &&
3323                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3324                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3325                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3326                   xfrm_state_addr_cmp(tmpl, x, family)) &&
3327                 (if_id == 0 || if_id == x->if_id);
3328 }
3329
3330 /*
3331  * 0 or more than 0 is returned when validation is succeeded (either bypass
3332  * because of optional transport mode, or next index of the matched secpath
3333  * state with the template.
3334  * -1 is returned when no matching template is found.
3335  * Otherwise "-2 - errored_index" is returned.
3336  */
3337 static inline int
3338 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3339                unsigned short family, u32 if_id)
3340 {
3341         int idx = start;
3342
3343         if (tmpl->optional) {
3344                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3345                         return start;
3346         } else
3347                 start = -1;
3348         for (; idx < sp->len; idx++) {
3349                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
3350                         return ++idx;
3351                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3352                         if (start == -1)
3353                                 start = -2-idx;
3354                         break;
3355                 }
3356         }
3357         return start;
3358 }
3359
3360 static void
3361 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3362 {
3363         const struct iphdr *iph = ip_hdr(skb);
3364         int ihl = iph->ihl;
3365         u8 *xprth = skb_network_header(skb) + ihl * 4;
3366         struct flowi4 *fl4 = &fl->u.ip4;
3367         int oif = 0;
3368
3369         if (skb_dst(skb) && skb_dst(skb)->dev)
3370                 oif = skb_dst(skb)->dev->ifindex;
3371
3372         memset(fl4, 0, sizeof(struct flowi4));
3373         fl4->flowi4_mark = skb->mark;
3374         fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3375
3376         fl4->flowi4_proto = iph->protocol;
3377         fl4->daddr = reverse ? iph->saddr : iph->daddr;
3378         fl4->saddr = reverse ? iph->daddr : iph->saddr;
3379         fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK;
3380
3381         if (!ip_is_fragment(iph)) {
3382                 switch (iph->protocol) {
3383                 case IPPROTO_UDP:
3384                 case IPPROTO_UDPLITE:
3385                 case IPPROTO_TCP:
3386                 case IPPROTO_SCTP:
3387                 case IPPROTO_DCCP:
3388                         if (xprth + 4 < skb->data ||
3389                             pskb_may_pull(skb, xprth + 4 - skb->data)) {
3390                                 __be16 *ports;
3391
3392                                 xprth = skb_network_header(skb) + ihl * 4;
3393                                 ports = (__be16 *)xprth;
3394
3395                                 fl4->fl4_sport = ports[!!reverse];
3396                                 fl4->fl4_dport = ports[!reverse];
3397                         }
3398                         break;
3399                 case IPPROTO_ICMP:
3400                         if (xprth + 2 < skb->data ||
3401                             pskb_may_pull(skb, xprth + 2 - skb->data)) {
3402                                 u8 *icmp;
3403
3404                                 xprth = skb_network_header(skb) + ihl * 4;
3405                                 icmp = xprth;
3406
3407                                 fl4->fl4_icmp_type = icmp[0];
3408                                 fl4->fl4_icmp_code = icmp[1];
3409                         }
3410                         break;
3411                 case IPPROTO_GRE:
3412                         if (xprth + 12 < skb->data ||
3413                             pskb_may_pull(skb, xprth + 12 - skb->data)) {
3414                                 __be16 *greflags;
3415                                 __be32 *gre_hdr;
3416
3417                                 xprth = skb_network_header(skb) + ihl * 4;
3418                                 greflags = (__be16 *)xprth;
3419                                 gre_hdr = (__be32 *)xprth;
3420
3421                                 if (greflags[0] & GRE_KEY) {
3422                                         if (greflags[0] & GRE_CSUM)
3423                                                 gre_hdr++;
3424                                         fl4->fl4_gre_key = gre_hdr[1];
3425                                 }
3426                         }
3427                         break;
3428                 default:
3429                         break;
3430                 }
3431         }
3432 }
3433
3434 #if IS_ENABLED(CONFIG_IPV6)
3435 static void
3436 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3437 {
3438         struct flowi6 *fl6 = &fl->u.ip6;
3439         int onlyproto = 0;
3440         const struct ipv6hdr *hdr = ipv6_hdr(skb);
3441         u32 offset = sizeof(*hdr);
3442         struct ipv6_opt_hdr *exthdr;
3443         const unsigned char *nh = skb_network_header(skb);
3444         u16 nhoff = IP6CB(skb)->nhoff;
3445         int oif = 0;
3446         u8 nexthdr;
3447
3448         if (!nhoff)
3449                 nhoff = offsetof(struct ipv6hdr, nexthdr);
3450
3451         nexthdr = nh[nhoff];
3452
3453         if (skb_dst(skb) && skb_dst(skb)->dev)
3454                 oif = skb_dst(skb)->dev->ifindex;
3455
3456         memset(fl6, 0, sizeof(struct flowi6));
3457         fl6->flowi6_mark = skb->mark;
3458         fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3459
3460         fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3461         fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3462
3463         while (nh + offset + sizeof(*exthdr) < skb->data ||
3464                pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3465                 nh = skb_network_header(skb);
3466                 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3467
3468                 switch (nexthdr) {
3469                 case NEXTHDR_FRAGMENT:
3470                         onlyproto = 1;
3471                         fallthrough;
3472                 case NEXTHDR_ROUTING:
3473                 case NEXTHDR_HOP:
3474                 case NEXTHDR_DEST:
3475                         offset += ipv6_optlen(exthdr);
3476                         nexthdr = exthdr->nexthdr;
3477                         break;
3478                 case IPPROTO_UDP:
3479                 case IPPROTO_UDPLITE:
3480                 case IPPROTO_TCP:
3481                 case IPPROTO_SCTP:
3482                 case IPPROTO_DCCP:
3483                         if (!onlyproto && (nh + offset + 4 < skb->data ||
3484                              pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3485                                 __be16 *ports;
3486
3487                                 nh = skb_network_header(skb);
3488                                 ports = (__be16 *)(nh + offset);
3489                                 fl6->fl6_sport = ports[!!reverse];
3490                                 fl6->fl6_dport = ports[!reverse];
3491                         }
3492                         fl6->flowi6_proto = nexthdr;
3493                         return;
3494                 case IPPROTO_ICMPV6:
3495                         if (!onlyproto && (nh + offset + 2 < skb->data ||
3496                             pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3497                                 u8 *icmp;
3498
3499                                 nh = skb_network_header(skb);
3500                                 icmp = (u8 *)(nh + offset);
3501                                 fl6->fl6_icmp_type = icmp[0];
3502                                 fl6->fl6_icmp_code = icmp[1];
3503                         }
3504                         fl6->flowi6_proto = nexthdr;
3505                         return;
3506                 case IPPROTO_GRE:
3507                         if (!onlyproto &&
3508                             (nh + offset + 12 < skb->data ||
3509                              pskb_may_pull(skb, nh + offset + 12 - skb->data))) {
3510                                 struct gre_base_hdr *gre_hdr;
3511                                 __be32 *gre_key;
3512
3513                                 nh = skb_network_header(skb);
3514                                 gre_hdr = (struct gre_base_hdr *)(nh + offset);
3515                                 gre_key = (__be32 *)(gre_hdr + 1);
3516
3517                                 if (gre_hdr->flags & GRE_KEY) {
3518                                         if (gre_hdr->flags & GRE_CSUM)
3519                                                 gre_key++;
3520                                         fl6->fl6_gre_key = *gre_key;
3521                                 }
3522                         }
3523                         fl6->flowi6_proto = nexthdr;
3524                         return;
3525
3526 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3527                 case IPPROTO_MH:
3528                         offset += ipv6_optlen(exthdr);
3529                         if (!onlyproto && (nh + offset + 3 < skb->data ||
3530                             pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3531                                 struct ip6_mh *mh;
3532
3533                                 nh = skb_network_header(skb);
3534                                 mh = (struct ip6_mh *)(nh + offset);
3535                                 fl6->fl6_mh_type = mh->ip6mh_type;
3536                         }
3537                         fl6->flowi6_proto = nexthdr;
3538                         return;
3539 #endif
3540                 default:
3541                         fl6->flowi6_proto = nexthdr;
3542                         return;
3543                 }
3544         }
3545 }
3546 #endif
3547
3548 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3549                           unsigned int family, int reverse)
3550 {
3551         switch (family) {
3552         case AF_INET:
3553                 decode_session4(skb, fl, reverse);
3554                 break;
3555 #if IS_ENABLED(CONFIG_IPV6)
3556         case AF_INET6:
3557                 decode_session6(skb, fl, reverse);
3558                 break;
3559 #endif
3560         default:
3561                 return -EAFNOSUPPORT;
3562         }
3563
3564         return security_xfrm_decode_session(skb, &fl->flowi_secid);
3565 }
3566 EXPORT_SYMBOL(__xfrm_decode_session);
3567
3568 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3569 {
3570         for (; k < sp->len; k++) {
3571                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3572                         *idxp = k;
3573                         return 1;
3574                 }
3575         }
3576
3577         return 0;
3578 }
3579
3580 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3581                         unsigned short family)
3582 {
3583         struct net *net = dev_net(skb->dev);
3584         struct xfrm_policy *pol;
3585         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3586         int npols = 0;
3587         int xfrm_nr;
3588         int pi;
3589         int reverse;
3590         struct flowi fl;
3591         int xerr_idx = -1;
3592         const struct xfrm_if_cb *ifcb;
3593         struct sec_path *sp;
3594         u32 if_id = 0;
3595
3596         rcu_read_lock();
3597         ifcb = xfrm_if_get_cb();
3598
3599         if (ifcb) {
3600                 struct xfrm_if_decode_session_result r;
3601
3602                 if (ifcb->decode_session(skb, family, &r)) {
3603                         if_id = r.if_id;
3604                         net = r.net;
3605                 }
3606         }
3607         rcu_read_unlock();
3608
3609         reverse = dir & ~XFRM_POLICY_MASK;
3610         dir &= XFRM_POLICY_MASK;
3611
3612         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3613                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3614                 return 0;
3615         }
3616
3617         nf_nat_decode_session(skb, &fl, family);
3618
3619         /* First, check used SA against their selectors. */
3620         sp = skb_sec_path(skb);
3621         if (sp) {
3622                 int i;
3623
3624                 for (i = sp->len - 1; i >= 0; i--) {
3625                         struct xfrm_state *x = sp->xvec[i];
3626                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
3627                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3628                                 return 0;
3629                         }
3630                 }
3631         }
3632
3633         pol = NULL;
3634         sk = sk_to_full_sk(sk);
3635         if (sk && sk->sk_policy[dir]) {
3636                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3637                 if (IS_ERR(pol)) {
3638                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3639                         return 0;
3640                 }
3641         }
3642
3643         if (!pol)
3644                 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3645
3646         if (IS_ERR(pol)) {
3647                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3648                 return 0;
3649         }
3650
3651         if (!pol) {
3652                 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3653                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3654                         return 0;
3655                 }
3656
3657                 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3658                         xfrm_secpath_reject(xerr_idx, skb, &fl);
3659                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3660                         return 0;
3661                 }
3662                 return 1;
3663         }
3664
3665         /* This lockless write can happen from different cpus. */
3666         WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
3667
3668         pols[0] = pol;
3669         npols++;
3670 #ifdef CONFIG_XFRM_SUB_POLICY
3671         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3672                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3673                                                     &fl, family,
3674                                                     XFRM_POLICY_IN, if_id);
3675                 if (pols[1]) {
3676                         if (IS_ERR(pols[1])) {
3677                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3678                                 xfrm_pol_put(pols[0]);
3679                                 return 0;
3680                         }
3681                         /* This write can happen from different cpus. */
3682                         WRITE_ONCE(pols[1]->curlft.use_time,
3683                                    ktime_get_real_seconds());
3684                         npols++;
3685                 }
3686         }
3687 #endif
3688
3689         if (pol->action == XFRM_POLICY_ALLOW) {
3690                 static struct sec_path dummy;
3691                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3692                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3693                 struct xfrm_tmpl **tpp = tp;
3694                 int ti = 0;
3695                 int i, k;
3696
3697                 sp = skb_sec_path(skb);
3698                 if (!sp)
3699                         sp = &dummy;
3700
3701                 for (pi = 0; pi < npols; pi++) {
3702                         if (pols[pi] != pol &&
3703                             pols[pi]->action != XFRM_POLICY_ALLOW) {
3704                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3705                                 goto reject;
3706                         }
3707                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3708                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3709                                 goto reject_error;
3710                         }
3711                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
3712                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3713                 }
3714                 xfrm_nr = ti;
3715
3716                 if (npols > 1) {
3717                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3718                         tpp = stp;
3719                 }
3720
3721                 /* For each tunnel xfrm, find the first matching tmpl.
3722                  * For each tmpl before that, find corresponding xfrm.
3723                  * Order is _important_. Later we will implement
3724                  * some barriers, but at the moment barriers
3725                  * are implied between each two transformations.
3726                  */
3727                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3728                         k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
3729                         if (k < 0) {
3730                                 if (k < -1)
3731                                         /* "-2 - errored_index" returned */
3732                                         xerr_idx = -(2+k);
3733                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3734                                 goto reject;
3735                         }
3736                 }
3737
3738                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3739                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3740                         goto reject;
3741                 }
3742
3743                 xfrm_pols_put(pols, npols);
3744                 return 1;
3745         }
3746         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3747
3748 reject:
3749         xfrm_secpath_reject(xerr_idx, skb, &fl);
3750 reject_error:
3751         xfrm_pols_put(pols, npols);
3752         return 0;
3753 }
3754 EXPORT_SYMBOL(__xfrm_policy_check);
3755
3756 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3757 {
3758         struct net *net = dev_net(skb->dev);
3759         struct flowi fl;
3760         struct dst_entry *dst;
3761         int res = 1;
3762
3763         if (xfrm_decode_session(skb, &fl, family) < 0) {
3764                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3765                 return 0;
3766         }
3767
3768         skb_dst_force(skb);
3769         if (!skb_dst(skb)) {
3770                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3771                 return 0;
3772         }
3773
3774         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3775         if (IS_ERR(dst)) {
3776                 res = 0;
3777                 dst = NULL;
3778         }
3779         skb_dst_set(skb, dst);
3780         return res;
3781 }
3782 EXPORT_SYMBOL(__xfrm_route_forward);
3783
3784 /* Optimize later using cookies and generation ids. */
3785
3786 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3787 {
3788         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3789          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3790          * get validated by dst_ops->check on every use.  We do this
3791          * because when a normal route referenced by an XFRM dst is
3792          * obsoleted we do not go looking around for all parent
3793          * referencing XFRM dsts so that we can invalidate them.  It
3794          * is just too much work.  Instead we make the checks here on
3795          * every use.  For example:
3796          *
3797          *      XFRM dst A --> IPv4 dst X
3798          *
3799          * X is the "xdst->route" of A (X is also the "dst->path" of A
3800          * in this example).  If X is marked obsolete, "A" will not
3801          * notice.  That's what we are validating here via the
3802          * stale_bundle() check.
3803          *
3804          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3805          * be marked on it.
3806          * This will force stale_bundle() to fail on any xdst bundle with
3807          * this dst linked in it.
3808          */
3809         if (dst->obsolete < 0 && !stale_bundle(dst))
3810                 return dst;
3811
3812         return NULL;
3813 }
3814
3815 static int stale_bundle(struct dst_entry *dst)
3816 {
3817         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3818 }
3819
3820 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3821 {
3822         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3823                 dst->dev = blackhole_netdev;
3824                 dev_hold(dst->dev);
3825                 dev_put(dev);
3826         }
3827 }
3828 EXPORT_SYMBOL(xfrm_dst_ifdown);
3829
3830 static void xfrm_link_failure(struct sk_buff *skb)
3831 {
3832         /* Impossible. Such dst must be popped before reaches point of failure. */
3833 }
3834
3835 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3836 {
3837         if (dst) {
3838                 if (dst->obsolete) {
3839                         dst_release(dst);
3840                         dst = NULL;
3841                 }
3842         }
3843         return dst;
3844 }
3845
3846 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3847 {
3848         while (nr--) {
3849                 struct xfrm_dst *xdst = bundle[nr];
3850                 u32 pmtu, route_mtu_cached;
3851                 struct dst_entry *dst;
3852
3853                 dst = &xdst->u.dst;
3854                 pmtu = dst_mtu(xfrm_dst_child(dst));
3855                 xdst->child_mtu_cached = pmtu;
3856
3857                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3858
3859                 route_mtu_cached = dst_mtu(xdst->route);
3860                 xdst->route_mtu_cached = route_mtu_cached;
3861
3862                 if (pmtu > route_mtu_cached)
3863                         pmtu = route_mtu_cached;
3864
3865                 dst_metric_set(dst, RTAX_MTU, pmtu);
3866         }
3867 }
3868
3869 /* Check that the bundle accepts the flow and its components are
3870  * still valid.
3871  */
3872
3873 static int xfrm_bundle_ok(struct xfrm_dst *first)
3874 {
3875         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3876         struct dst_entry *dst = &first->u.dst;
3877         struct xfrm_dst *xdst;
3878         int start_from, nr;
3879         u32 mtu;
3880
3881         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3882             (dst->dev && !netif_running(dst->dev)))
3883                 return 0;
3884
3885         if (dst->flags & DST_XFRM_QUEUE)
3886                 return 1;
3887
3888         start_from = nr = 0;
3889         do {
3890                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3891
3892                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3893                         return 0;
3894                 if (xdst->xfrm_genid != dst->xfrm->genid)
3895                         return 0;
3896                 if (xdst->num_pols > 0 &&
3897                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3898                         return 0;
3899
3900                 bundle[nr++] = xdst;
3901
3902                 mtu = dst_mtu(xfrm_dst_child(dst));
3903                 if (xdst->child_mtu_cached != mtu) {
3904                         start_from = nr;
3905                         xdst->child_mtu_cached = mtu;
3906                 }
3907
3908                 if (!dst_check(xdst->route, xdst->route_cookie))
3909                         return 0;
3910                 mtu = dst_mtu(xdst->route);
3911                 if (xdst->route_mtu_cached != mtu) {
3912                         start_from = nr;
3913                         xdst->route_mtu_cached = mtu;
3914                 }
3915
3916                 dst = xfrm_dst_child(dst);
3917         } while (dst->xfrm);
3918
3919         if (likely(!start_from))
3920                 return 1;
3921
3922         xdst = bundle[start_from - 1];
3923         mtu = xdst->child_mtu_cached;
3924         while (start_from--) {
3925                 dst = &xdst->u.dst;
3926
3927                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3928                 if (mtu > xdst->route_mtu_cached)
3929                         mtu = xdst->route_mtu_cached;
3930                 dst_metric_set(dst, RTAX_MTU, mtu);
3931                 if (!start_from)
3932                         break;
3933
3934                 xdst = bundle[start_from - 1];
3935                 xdst->child_mtu_cached = mtu;
3936         }
3937
3938         return 1;
3939 }
3940
3941 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3942 {
3943         return dst_metric_advmss(xfrm_dst_path(dst));
3944 }
3945
3946 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3947 {
3948         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3949
3950         return mtu ? : dst_mtu(xfrm_dst_path(dst));
3951 }
3952
3953 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3954                                         const void *daddr)
3955 {
3956         while (dst->xfrm) {
3957                 const struct xfrm_state *xfrm = dst->xfrm;
3958
3959                 dst = xfrm_dst_child(dst);
3960
3961                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3962                         continue;
3963                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3964                         daddr = xfrm->coaddr;
3965                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3966                         daddr = &xfrm->id.daddr;
3967         }
3968         return daddr;
3969 }
3970
3971 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3972                                            struct sk_buff *skb,
3973                                            const void *daddr)
3974 {
3975         const struct dst_entry *path = xfrm_dst_path(dst);
3976
3977         if (!skb)
3978                 daddr = xfrm_get_dst_nexthop(dst, daddr);
3979         return path->ops->neigh_lookup(path, skb, daddr);
3980 }
3981
3982 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3983 {
3984         const struct dst_entry *path = xfrm_dst_path(dst);
3985
3986         daddr = xfrm_get_dst_nexthop(dst, daddr);
3987         path->ops->confirm_neigh(path, daddr);
3988 }
3989
3990 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3991 {
3992         int err = 0;
3993
3994         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3995                 return -EAFNOSUPPORT;
3996
3997         spin_lock(&xfrm_policy_afinfo_lock);
3998         if (unlikely(xfrm_policy_afinfo[family] != NULL))
3999                 err = -EEXIST;
4000         else {
4001                 struct dst_ops *dst_ops = afinfo->dst_ops;
4002                 if (likely(dst_ops->kmem_cachep == NULL))
4003                         dst_ops->kmem_cachep = xfrm_dst_cache;
4004                 if (likely(dst_ops->check == NULL))
4005                         dst_ops->check = xfrm_dst_check;
4006                 if (likely(dst_ops->default_advmss == NULL))
4007                         dst_ops->default_advmss = xfrm_default_advmss;
4008                 if (likely(dst_ops->mtu == NULL))
4009                         dst_ops->mtu = xfrm_mtu;
4010                 if (likely(dst_ops->negative_advice == NULL))
4011                         dst_ops->negative_advice = xfrm_negative_advice;
4012                 if (likely(dst_ops->link_failure == NULL))
4013                         dst_ops->link_failure = xfrm_link_failure;
4014                 if (likely(dst_ops->neigh_lookup == NULL))
4015                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
4016                 if (likely(!dst_ops->confirm_neigh))
4017                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
4018                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
4019         }
4020         spin_unlock(&xfrm_policy_afinfo_lock);
4021
4022         return err;
4023 }
4024 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
4025
4026 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
4027 {
4028         struct dst_ops *dst_ops = afinfo->dst_ops;
4029         int i;
4030
4031         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
4032                 if (xfrm_policy_afinfo[i] != afinfo)
4033                         continue;
4034                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
4035                 break;
4036         }
4037
4038         synchronize_rcu();
4039
4040         dst_ops->kmem_cachep = NULL;
4041         dst_ops->check = NULL;
4042         dst_ops->negative_advice = NULL;
4043         dst_ops->link_failure = NULL;
4044 }
4045 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
4046
4047 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
4048 {
4049         spin_lock(&xfrm_if_cb_lock);
4050         rcu_assign_pointer(xfrm_if_cb, ifcb);
4051         spin_unlock(&xfrm_if_cb_lock);
4052 }
4053 EXPORT_SYMBOL(xfrm_if_register_cb);
4054
4055 void xfrm_if_unregister_cb(void)
4056 {
4057         RCU_INIT_POINTER(xfrm_if_cb, NULL);
4058         synchronize_rcu();
4059 }
4060 EXPORT_SYMBOL(xfrm_if_unregister_cb);
4061
4062 #ifdef CONFIG_XFRM_STATISTICS
4063 static int __net_init xfrm_statistics_init(struct net *net)
4064 {
4065         int rv;
4066         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
4067         if (!net->mib.xfrm_statistics)
4068                 return -ENOMEM;
4069         rv = xfrm_proc_init(net);
4070         if (rv < 0)
4071                 free_percpu(net->mib.xfrm_statistics);
4072         return rv;
4073 }
4074
4075 static void xfrm_statistics_fini(struct net *net)
4076 {
4077         xfrm_proc_fini(net);
4078         free_percpu(net->mib.xfrm_statistics);
4079 }
4080 #else
4081 static int __net_init xfrm_statistics_init(struct net *net)
4082 {
4083         return 0;
4084 }
4085
4086 static void xfrm_statistics_fini(struct net *net)
4087 {
4088 }
4089 #endif
4090
4091 static int __net_init xfrm_policy_init(struct net *net)
4092 {
4093         unsigned int hmask, sz;
4094         int dir, err;
4095
4096         if (net_eq(net, &init_net)) {
4097                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4098                                            sizeof(struct xfrm_dst),
4099                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4100                                            NULL);
4101                 err = rhashtable_init(&xfrm_policy_inexact_table,
4102                                       &xfrm_pol_inexact_params);
4103                 BUG_ON(err);
4104         }
4105
4106         hmask = 8 - 1;
4107         sz = (hmask+1) * sizeof(struct hlist_head);
4108
4109         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4110         if (!net->xfrm.policy_byidx)
4111                 goto out_byidx;
4112         net->xfrm.policy_idx_hmask = hmask;
4113
4114         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4115                 struct xfrm_policy_hash *htab;
4116
4117                 net->xfrm.policy_count[dir] = 0;
4118                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4119                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4120
4121                 htab = &net->xfrm.policy_bydst[dir];
4122                 htab->table = xfrm_hash_alloc(sz);
4123                 if (!htab->table)
4124                         goto out_bydst;
4125                 htab->hmask = hmask;
4126                 htab->dbits4 = 32;
4127                 htab->sbits4 = 32;
4128                 htab->dbits6 = 128;
4129                 htab->sbits6 = 128;
4130         }
4131         net->xfrm.policy_hthresh.lbits4 = 32;
4132         net->xfrm.policy_hthresh.rbits4 = 32;
4133         net->xfrm.policy_hthresh.lbits6 = 128;
4134         net->xfrm.policy_hthresh.rbits6 = 128;
4135
4136         seqlock_init(&net->xfrm.policy_hthresh.lock);
4137
4138         INIT_LIST_HEAD(&net->xfrm.policy_all);
4139         INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4140         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4141         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4142         return 0;
4143
4144 out_bydst:
4145         for (dir--; dir >= 0; dir--) {
4146                 struct xfrm_policy_hash *htab;
4147
4148                 htab = &net->xfrm.policy_bydst[dir];
4149                 xfrm_hash_free(htab->table, sz);
4150         }
4151         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4152 out_byidx:
4153         return -ENOMEM;
4154 }
4155
4156 static void xfrm_policy_fini(struct net *net)
4157 {
4158         struct xfrm_pol_inexact_bin *b, *t;
4159         unsigned int sz;
4160         int dir;
4161
4162         flush_work(&net->xfrm.policy_hash_work);
4163 #ifdef CONFIG_XFRM_SUB_POLICY
4164         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4165 #endif
4166         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4167
4168         WARN_ON(!list_empty(&net->xfrm.policy_all));
4169
4170         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4171                 struct xfrm_policy_hash *htab;
4172
4173                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4174
4175                 htab = &net->xfrm.policy_bydst[dir];
4176                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4177                 WARN_ON(!hlist_empty(htab->table));
4178                 xfrm_hash_free(htab->table, sz);
4179         }
4180
4181         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4182         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4183         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4184
4185         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4186         list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4187                 __xfrm_policy_inexact_prune_bin(b, true);
4188         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4189 }
4190
4191 static int __net_init xfrm_net_init(struct net *net)
4192 {
4193         int rv;
4194
4195         /* Initialize the per-net locks here */
4196         spin_lock_init(&net->xfrm.xfrm_state_lock);
4197         spin_lock_init(&net->xfrm.xfrm_policy_lock);
4198         seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4199         mutex_init(&net->xfrm.xfrm_cfg_mutex);
4200         net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4201         net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4202         net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4203
4204         rv = xfrm_statistics_init(net);
4205         if (rv < 0)
4206                 goto out_statistics;
4207         rv = xfrm_state_init(net);
4208         if (rv < 0)
4209                 goto out_state;
4210         rv = xfrm_policy_init(net);
4211         if (rv < 0)
4212                 goto out_policy;
4213         rv = xfrm_sysctl_init(net);
4214         if (rv < 0)
4215                 goto out_sysctl;
4216
4217         return 0;
4218
4219 out_sysctl:
4220         xfrm_policy_fini(net);
4221 out_policy:
4222         xfrm_state_fini(net);
4223 out_state:
4224         xfrm_statistics_fini(net);
4225 out_statistics:
4226         return rv;
4227 }
4228
4229 static void __net_exit xfrm_net_exit(struct net *net)
4230 {
4231         xfrm_sysctl_fini(net);
4232         xfrm_policy_fini(net);
4233         xfrm_state_fini(net);
4234         xfrm_statistics_fini(net);
4235 }
4236
4237 static struct pernet_operations __net_initdata xfrm_net_ops = {
4238         .init = xfrm_net_init,
4239         .exit = xfrm_net_exit,
4240 };
4241
4242 void __init xfrm_init(void)
4243 {
4244         register_pernet_subsys(&xfrm_net_ops);
4245         xfrm_dev_init();
4246         xfrm_input_init();
4247
4248 #ifdef CONFIG_XFRM_ESPINTCP
4249         espintcp_init();
4250 #endif
4251 }
4252
4253 #ifdef CONFIG_AUDITSYSCALL
4254 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4255                                          struct audit_buffer *audit_buf)
4256 {
4257         struct xfrm_sec_ctx *ctx = xp->security;
4258         struct xfrm_selector *sel = &xp->selector;
4259
4260         if (ctx)
4261                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4262                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4263
4264         switch (sel->family) {
4265         case AF_INET:
4266                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4267                 if (sel->prefixlen_s != 32)
4268                         audit_log_format(audit_buf, " src_prefixlen=%d",
4269                                          sel->prefixlen_s);
4270                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4271                 if (sel->prefixlen_d != 32)
4272                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4273                                          sel->prefixlen_d);
4274                 break;
4275         case AF_INET6:
4276                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4277                 if (sel->prefixlen_s != 128)
4278                         audit_log_format(audit_buf, " src_prefixlen=%d",
4279                                          sel->prefixlen_s);
4280                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4281                 if (sel->prefixlen_d != 128)
4282                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4283                                          sel->prefixlen_d);
4284                 break;
4285         }
4286 }
4287
4288 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4289 {
4290         struct audit_buffer *audit_buf;
4291
4292         audit_buf = xfrm_audit_start("SPD-add");
4293         if (audit_buf == NULL)
4294                 return;
4295         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4296         audit_log_format(audit_buf, " res=%u", result);
4297         xfrm_audit_common_policyinfo(xp, audit_buf);
4298         audit_log_end(audit_buf);
4299 }
4300 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4301
4302 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4303                               bool task_valid)
4304 {
4305         struct audit_buffer *audit_buf;
4306
4307         audit_buf = xfrm_audit_start("SPD-delete");
4308         if (audit_buf == NULL)
4309                 return;
4310         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4311         audit_log_format(audit_buf, " res=%u", result);
4312         xfrm_audit_common_policyinfo(xp, audit_buf);
4313         audit_log_end(audit_buf);
4314 }
4315 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4316 #endif
4317
4318 #ifdef CONFIG_XFRM_MIGRATE
4319 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4320                                         const struct xfrm_selector *sel_tgt)
4321 {
4322         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4323                 if (sel_tgt->family == sel_cmp->family &&
4324                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4325                                     sel_cmp->family) &&
4326                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4327                                     sel_cmp->family) &&
4328                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4329                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4330                         return true;
4331                 }
4332         } else {
4333                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4334                         return true;
4335                 }
4336         }
4337         return false;
4338 }
4339
4340 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4341                                                     u8 dir, u8 type, struct net *net, u32 if_id)
4342 {
4343         struct xfrm_policy *pol, *ret = NULL;
4344         struct hlist_head *chain;
4345         u32 priority = ~0U;
4346
4347         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4348         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4349         hlist_for_each_entry(pol, chain, bydst) {
4350                 if ((if_id == 0 || pol->if_id == if_id) &&
4351                     xfrm_migrate_selector_match(sel, &pol->selector) &&
4352                     pol->type == type) {
4353                         ret = pol;
4354                         priority = ret->priority;
4355                         break;
4356                 }
4357         }
4358         chain = &net->xfrm.policy_inexact[dir];
4359         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4360                 if ((pol->priority >= priority) && ret)
4361                         break;
4362
4363                 if ((if_id == 0 || pol->if_id == if_id) &&
4364                     xfrm_migrate_selector_match(sel, &pol->selector) &&
4365                     pol->type == type) {
4366                         ret = pol;
4367                         break;
4368                 }
4369         }
4370
4371         xfrm_pol_hold(ret);
4372
4373         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4374
4375         return ret;
4376 }
4377
4378 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4379 {
4380         int match = 0;
4381
4382         if (t->mode == m->mode && t->id.proto == m->proto &&
4383             (m->reqid == 0 || t->reqid == m->reqid)) {
4384                 switch (t->mode) {
4385                 case XFRM_MODE_TUNNEL:
4386                 case XFRM_MODE_BEET:
4387                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4388                                             m->old_family) &&
4389                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
4390                                             m->old_family)) {
4391                                 match = 1;
4392                         }
4393                         break;
4394                 case XFRM_MODE_TRANSPORT:
4395                         /* in case of transport mode, template does not store
4396                            any IP addresses, hence we just compare mode and
4397                            protocol */
4398                         match = 1;
4399                         break;
4400                 default:
4401                         break;
4402                 }
4403         }
4404         return match;
4405 }
4406
4407 /* update endpoint address(es) of template(s) */
4408 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4409                                struct xfrm_migrate *m, int num_migrate,
4410                                struct netlink_ext_ack *extack)
4411 {
4412         struct xfrm_migrate *mp;
4413         int i, j, n = 0;
4414
4415         write_lock_bh(&pol->lock);
4416         if (unlikely(pol->walk.dead)) {
4417                 /* target policy has been deleted */
4418                 NL_SET_ERR_MSG(extack, "Target policy not found");
4419                 write_unlock_bh(&pol->lock);
4420                 return -ENOENT;
4421         }
4422
4423         for (i = 0; i < pol->xfrm_nr; i++) {
4424                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4425                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4426                                 continue;
4427                         n++;
4428                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4429                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4430                                 continue;
4431                         /* update endpoints */
4432                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4433                                sizeof(pol->xfrm_vec[i].id.daddr));
4434                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4435                                sizeof(pol->xfrm_vec[i].saddr));
4436                         pol->xfrm_vec[i].encap_family = mp->new_family;
4437                         /* flush bundles */
4438                         atomic_inc(&pol->genid);
4439                 }
4440         }
4441
4442         write_unlock_bh(&pol->lock);
4443
4444         if (!n)
4445                 return -ENODATA;
4446
4447         return 0;
4448 }
4449
4450 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
4451                               struct netlink_ext_ack *extack)
4452 {
4453         int i, j;
4454
4455         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
4456                 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
4457                 return -EINVAL;
4458         }
4459
4460         for (i = 0; i < num_migrate; i++) {
4461                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4462                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
4463                         NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
4464                         return -EINVAL;
4465                 }
4466
4467                 /* check if there is any duplicated entry */
4468                 for (j = i + 1; j < num_migrate; j++) {
4469                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4470                                     sizeof(m[i].old_daddr)) &&
4471                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4472                                     sizeof(m[i].old_saddr)) &&
4473                             m[i].proto == m[j].proto &&
4474                             m[i].mode == m[j].mode &&
4475                             m[i].reqid == m[j].reqid &&
4476                             m[i].old_family == m[j].old_family) {
4477                                 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
4478                                 return -EINVAL;
4479                         }
4480                 }
4481         }
4482
4483         return 0;
4484 }
4485
4486 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4487                  struct xfrm_migrate *m, int num_migrate,
4488                  struct xfrm_kmaddress *k, struct net *net,
4489                  struct xfrm_encap_tmpl *encap, u32 if_id,
4490                  struct netlink_ext_ack *extack)
4491 {
4492         int i, err, nx_cur = 0, nx_new = 0;
4493         struct xfrm_policy *pol = NULL;
4494         struct xfrm_state *x, *xc;
4495         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4496         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4497         struct xfrm_migrate *mp;
4498
4499         /* Stage 0 - sanity checks */
4500         err = xfrm_migrate_check(m, num_migrate, extack);
4501         if (err < 0)
4502                 goto out;
4503
4504         if (dir >= XFRM_POLICY_MAX) {
4505                 NL_SET_ERR_MSG(extack, "Invalid policy direction");
4506                 err = -EINVAL;
4507                 goto out;
4508         }
4509
4510         /* Stage 1 - find policy */
4511         pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
4512         if (!pol) {
4513                 NL_SET_ERR_MSG(extack, "Target policy not found");
4514                 err = -ENOENT;
4515                 goto out;
4516         }
4517
4518         /* Stage 2 - find and update state(s) */
4519         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4520                 if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4521                         x_cur[nx_cur] = x;
4522                         nx_cur++;
4523                         xc = xfrm_state_migrate(x, mp, encap);
4524                         if (xc) {
4525                                 x_new[nx_new] = xc;
4526                                 nx_new++;
4527                         } else {
4528                                 err = -ENODATA;
4529                                 goto restore_state;
4530                         }
4531                 }
4532         }
4533
4534         /* Stage 3 - update policy */
4535         err = xfrm_policy_migrate(pol, m, num_migrate, extack);
4536         if (err < 0)
4537                 goto restore_state;
4538
4539         /* Stage 4 - delete old state(s) */
4540         if (nx_cur) {
4541                 xfrm_states_put(x_cur, nx_cur);
4542                 xfrm_states_delete(x_cur, nx_cur);
4543         }
4544
4545         /* Stage 5 - announce */
4546         km_migrate(sel, dir, type, m, num_migrate, k, encap);
4547
4548         xfrm_pol_put(pol);
4549
4550         return 0;
4551 out:
4552         return err;
4553
4554 restore_state:
4555         if (pol)
4556                 xfrm_pol_put(pol);
4557         if (nx_cur)
4558                 xfrm_states_put(x_cur, nx_cur);
4559         if (nx_new)
4560                 xfrm_states_delete(x_new, nx_new);
4561
4562         return err;
4563 }
4564 EXPORT_SYMBOL(xfrm_migrate);
4565 #endif