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->walk.dead || !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                 if (policy->walk.dead)
1260                         continue;
1261
1262                 dir = xfrm_policy_id2dir(policy->index);
1263                 if (dir >= XFRM_POLICY_MAX)
1264                         continue;
1265
1266                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1267                         if (policy->family == AF_INET) {
1268                                 dbits = rbits4;
1269                                 sbits = lbits4;
1270                         } else {
1271                                 dbits = rbits6;
1272                                 sbits = lbits6;
1273                         }
1274                 } else {
1275                         if (policy->family == AF_INET) {
1276                                 dbits = lbits4;
1277                                 sbits = rbits4;
1278                         } else {
1279                                 dbits = lbits6;
1280                                 sbits = rbits6;
1281                         }
1282                 }
1283
1284                 if (policy->selector.prefixlen_d < dbits ||
1285                     policy->selector.prefixlen_s < sbits)
1286                         continue;
1287
1288                 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1289                 if (!bin)
1290                         goto out_unlock;
1291
1292                 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1293                         goto out_unlock;
1294         }
1295
1296         /* reset the bydst and inexact table in all directions */
1297         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1298                 struct hlist_node *n;
1299
1300                 hlist_for_each_entry_safe(policy, n,
1301                                           &net->xfrm.policy_inexact[dir],
1302                                           bydst_inexact_list) {
1303                         hlist_del_rcu(&policy->bydst);
1304                         hlist_del_init(&policy->bydst_inexact_list);
1305                 }
1306
1307                 hmask = net->xfrm.policy_bydst[dir].hmask;
1308                 odst = net->xfrm.policy_bydst[dir].table;
1309                 for (i = hmask; i >= 0; i--) {
1310                         hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1311                                 hlist_del_rcu(&policy->bydst);
1312                 }
1313                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1314                         /* dir out => dst = remote, src = local */
1315                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1316                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1317                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1318                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1319                 } else {
1320                         /* dir in/fwd => dst = local, src = remote */
1321                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1322                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1323                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1324                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1325                 }
1326         }
1327
1328         /* re-insert all policies by order of creation */
1329         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1330                 if (policy->walk.dead)
1331                         continue;
1332                 dir = xfrm_policy_id2dir(policy->index);
1333                 if (dir >= XFRM_POLICY_MAX) {
1334                         /* skip socket policies */
1335                         continue;
1336                 }
1337                 newpos = NULL;
1338                 chain = policy_hash_bysel(net, &policy->selector,
1339                                           policy->family, dir);
1340
1341                 if (!chain) {
1342                         void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1343
1344                         WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1345                         continue;
1346                 }
1347
1348                 hlist_for_each_entry(pol, chain, bydst) {
1349                         if (policy->priority >= pol->priority)
1350                                 newpos = &pol->bydst;
1351                         else
1352                                 break;
1353                 }
1354                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1355                         hlist_add_behind_rcu(&policy->bydst, newpos);
1356                 else
1357                         hlist_add_head_rcu(&policy->bydst, chain);
1358         }
1359
1360 out_unlock:
1361         __xfrm_policy_inexact_flush(net);
1362         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1363         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1364
1365         mutex_unlock(&hash_resize_mutex);
1366 }
1367
1368 void xfrm_policy_hash_rebuild(struct net *net)
1369 {
1370         schedule_work(&net->xfrm.policy_hthresh.work);
1371 }
1372 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1373
1374 /* Generate new index... KAME seems to generate them ordered by cost
1375  * of an absolute inpredictability of ordering of rules. This will not pass. */
1376 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1377 {
1378         for (;;) {
1379                 struct hlist_head *list;
1380                 struct xfrm_policy *p;
1381                 u32 idx;
1382                 int found;
1383
1384                 if (!index) {
1385                         idx = (net->xfrm.idx_generator | dir);
1386                         net->xfrm.idx_generator += 8;
1387                 } else {
1388                         idx = index;
1389                         index = 0;
1390                 }
1391
1392                 if (idx == 0)
1393                         idx = 8;
1394                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1395                 found = 0;
1396                 hlist_for_each_entry(p, list, byidx) {
1397                         if (p->index == idx) {
1398                                 found = 1;
1399                                 break;
1400                         }
1401                 }
1402                 if (!found)
1403                         return idx;
1404         }
1405 }
1406
1407 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1408 {
1409         u32 *p1 = (u32 *) s1;
1410         u32 *p2 = (u32 *) s2;
1411         int len = sizeof(struct xfrm_selector) / sizeof(u32);
1412         int i;
1413
1414         for (i = 0; i < len; i++) {
1415                 if (p1[i] != p2[i])
1416                         return 1;
1417         }
1418
1419         return 0;
1420 }
1421
1422 static void xfrm_policy_requeue(struct xfrm_policy *old,
1423                                 struct xfrm_policy *new)
1424 {
1425         struct xfrm_policy_queue *pq = &old->polq;
1426         struct sk_buff_head list;
1427
1428         if (skb_queue_empty(&pq->hold_queue))
1429                 return;
1430
1431         __skb_queue_head_init(&list);
1432
1433         spin_lock_bh(&pq->hold_queue.lock);
1434         skb_queue_splice_init(&pq->hold_queue, &list);
1435         if (del_timer(&pq->hold_timer))
1436                 xfrm_pol_put(old);
1437         spin_unlock_bh(&pq->hold_queue.lock);
1438
1439         pq = &new->polq;
1440
1441         spin_lock_bh(&pq->hold_queue.lock);
1442         skb_queue_splice(&list, &pq->hold_queue);
1443         pq->timeout = XFRM_QUEUE_TMO_MIN;
1444         if (!mod_timer(&pq->hold_timer, jiffies))
1445                 xfrm_pol_hold(new);
1446         spin_unlock_bh(&pq->hold_queue.lock);
1447 }
1448
1449 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1450                                           struct xfrm_policy *pol)
1451 {
1452         return mark->v == pol->mark.v && mark->m == pol->mark.m;
1453 }
1454
1455 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1456 {
1457         const struct xfrm_pol_inexact_key *k = data;
1458         u32 a = k->type << 24 | k->dir << 16 | k->family;
1459
1460         return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1461                             seed);
1462 }
1463
1464 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1465 {
1466         const struct xfrm_pol_inexact_bin *b = data;
1467
1468         return xfrm_pol_bin_key(&b->k, 0, seed);
1469 }
1470
1471 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1472                             const void *ptr)
1473 {
1474         const struct xfrm_pol_inexact_key *key = arg->key;
1475         const struct xfrm_pol_inexact_bin *b = ptr;
1476         int ret;
1477
1478         if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1479                 return -1;
1480
1481         ret = b->k.dir ^ key->dir;
1482         if (ret)
1483                 return ret;
1484
1485         ret = b->k.type ^ key->type;
1486         if (ret)
1487                 return ret;
1488
1489         ret = b->k.family ^ key->family;
1490         if (ret)
1491                 return ret;
1492
1493         return b->k.if_id ^ key->if_id;
1494 }
1495
1496 static const struct rhashtable_params xfrm_pol_inexact_params = {
1497         .head_offset            = offsetof(struct xfrm_pol_inexact_bin, head),
1498         .hashfn                 = xfrm_pol_bin_key,
1499         .obj_hashfn             = xfrm_pol_bin_obj,
1500         .obj_cmpfn              = xfrm_pol_bin_cmp,
1501         .automatic_shrinking    = true,
1502 };
1503
1504 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1505                                             struct xfrm_policy *policy)
1506 {
1507         struct xfrm_policy *pol, *delpol = NULL;
1508         struct hlist_node *newpos = NULL;
1509         int i = 0;
1510
1511         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1512                 if (pol->type == policy->type &&
1513                     pol->if_id == policy->if_id &&
1514                     !selector_cmp(&pol->selector, &policy->selector) &&
1515                     xfrm_policy_mark_match(&policy->mark, pol) &&
1516                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1517                     !WARN_ON(delpol)) {
1518                         delpol = pol;
1519                         if (policy->priority > pol->priority)
1520                                 continue;
1521                 } else if (policy->priority >= pol->priority) {
1522                         newpos = &pol->bydst_inexact_list;
1523                         continue;
1524                 }
1525                 if (delpol)
1526                         break;
1527         }
1528
1529         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1530                 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1531         else
1532                 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1533
1534         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1535                 pol->pos = i;
1536                 i++;
1537         }
1538 }
1539
1540 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1541                                                    struct xfrm_policy *policy,
1542                                                    bool excl)
1543 {
1544         struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1545
1546         hlist_for_each_entry(pol, chain, bydst) {
1547                 if (pol->type == policy->type &&
1548                     pol->if_id == policy->if_id &&
1549                     !selector_cmp(&pol->selector, &policy->selector) &&
1550                     xfrm_policy_mark_match(&policy->mark, pol) &&
1551                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1552                     !WARN_ON(delpol)) {
1553                         if (excl)
1554                                 return ERR_PTR(-EEXIST);
1555                         delpol = pol;
1556                         if (policy->priority > pol->priority)
1557                                 continue;
1558                 } else if (policy->priority >= pol->priority) {
1559                         newpos = pol;
1560                         continue;
1561                 }
1562                 if (delpol)
1563                         break;
1564         }
1565
1566         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1567                 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1568         else
1569                 /* Packet offload policies enter to the head
1570                  * to speed-up lookups.
1571                  */
1572                 hlist_add_head_rcu(&policy->bydst, chain);
1573
1574         return delpol;
1575 }
1576
1577 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1578 {
1579         struct net *net = xp_net(policy);
1580         struct xfrm_policy *delpol;
1581         struct hlist_head *chain;
1582
1583         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1584         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1585         if (chain)
1586                 delpol = xfrm_policy_insert_list(chain, policy, excl);
1587         else
1588                 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1589
1590         if (IS_ERR(delpol)) {
1591                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1592                 return PTR_ERR(delpol);
1593         }
1594
1595         __xfrm_policy_link(policy, dir);
1596
1597         /* After previous checking, family can either be AF_INET or AF_INET6 */
1598         if (policy->family == AF_INET)
1599                 rt_genid_bump_ipv4(net);
1600         else
1601                 rt_genid_bump_ipv6(net);
1602
1603         if (delpol) {
1604                 xfrm_policy_requeue(delpol, policy);
1605                 __xfrm_policy_unlink(delpol, dir);
1606         }
1607         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1608         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1609         policy->curlft.add_time = ktime_get_real_seconds();
1610         policy->curlft.use_time = 0;
1611         if (!mod_timer(&policy->timer, jiffies + HZ))
1612                 xfrm_pol_hold(policy);
1613         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1614
1615         if (delpol)
1616                 xfrm_policy_kill(delpol);
1617         else if (xfrm_bydst_should_resize(net, dir, NULL))
1618                 schedule_work(&net->xfrm.policy_hash_work);
1619
1620         return 0;
1621 }
1622 EXPORT_SYMBOL(xfrm_policy_insert);
1623
1624 static struct xfrm_policy *
1625 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1626                         u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1627                         struct xfrm_sec_ctx *ctx)
1628 {
1629         struct xfrm_policy *pol;
1630
1631         if (!chain)
1632                 return NULL;
1633
1634         hlist_for_each_entry(pol, chain, bydst) {
1635                 if (pol->type == type &&
1636                     pol->if_id == if_id &&
1637                     xfrm_policy_mark_match(mark, pol) &&
1638                     !selector_cmp(sel, &pol->selector) &&
1639                     xfrm_sec_ctx_match(ctx, pol->security))
1640                         return pol;
1641         }
1642
1643         return NULL;
1644 }
1645
1646 struct xfrm_policy *
1647 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1648                       u8 type, int dir, struct xfrm_selector *sel,
1649                       struct xfrm_sec_ctx *ctx, int delete, int *err)
1650 {
1651         struct xfrm_pol_inexact_bin *bin = NULL;
1652         struct xfrm_policy *pol, *ret = NULL;
1653         struct hlist_head *chain;
1654
1655         *err = 0;
1656         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1657         chain = policy_hash_bysel(net, sel, sel->family, dir);
1658         if (!chain) {
1659                 struct xfrm_pol_inexact_candidates cand;
1660                 int i;
1661
1662                 bin = xfrm_policy_inexact_lookup(net, type,
1663                                                  sel->family, dir, if_id);
1664                 if (!bin) {
1665                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1666                         return NULL;
1667                 }
1668
1669                 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1670                                                          &sel->saddr,
1671                                                          &sel->daddr)) {
1672                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1673                         return NULL;
1674                 }
1675
1676                 pol = NULL;
1677                 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1678                         struct xfrm_policy *tmp;
1679
1680                         tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1681                                                       if_id, type, dir,
1682                                                       sel, ctx);
1683                         if (!tmp)
1684                                 continue;
1685
1686                         if (!pol || tmp->pos < pol->pos)
1687                                 pol = tmp;
1688                 }
1689         } else {
1690                 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1691                                               sel, ctx);
1692         }
1693
1694         if (pol) {
1695                 xfrm_pol_hold(pol);
1696                 if (delete) {
1697                         *err = security_xfrm_policy_delete(pol->security);
1698                         if (*err) {
1699                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1700                                 return pol;
1701                         }
1702                         __xfrm_policy_unlink(pol, dir);
1703                 }
1704                 ret = pol;
1705         }
1706         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1707
1708         if (ret && delete)
1709                 xfrm_policy_kill(ret);
1710         if (bin && delete)
1711                 xfrm_policy_inexact_prune_bin(bin);
1712         return ret;
1713 }
1714 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1715
1716 struct xfrm_policy *
1717 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1718                  u8 type, int dir, u32 id, int delete, int *err)
1719 {
1720         struct xfrm_policy *pol, *ret;
1721         struct hlist_head *chain;
1722
1723         *err = -ENOENT;
1724         if (xfrm_policy_id2dir(id) != dir)
1725                 return NULL;
1726
1727         *err = 0;
1728         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1729         chain = net->xfrm.policy_byidx + idx_hash(net, id);
1730         ret = NULL;
1731         hlist_for_each_entry(pol, chain, byidx) {
1732                 if (pol->type == type && pol->index == id &&
1733                     pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1734                         xfrm_pol_hold(pol);
1735                         if (delete) {
1736                                 *err = security_xfrm_policy_delete(
1737                                                                 pol->security);
1738                                 if (*err) {
1739                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1740                                         return pol;
1741                                 }
1742                                 __xfrm_policy_unlink(pol, dir);
1743                         }
1744                         ret = pol;
1745                         break;
1746                 }
1747         }
1748         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1749
1750         if (ret && delete)
1751                 xfrm_policy_kill(ret);
1752         return ret;
1753 }
1754 EXPORT_SYMBOL(xfrm_policy_byid);
1755
1756 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1757 static inline int
1758 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1759 {
1760         struct xfrm_policy *pol;
1761         int err = 0;
1762
1763         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1764                 if (pol->walk.dead ||
1765                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1766                     pol->type != type)
1767                         continue;
1768
1769                 err = security_xfrm_policy_delete(pol->security);
1770                 if (err) {
1771                         xfrm_audit_policy_delete(pol, 0, task_valid);
1772                         return err;
1773                 }
1774         }
1775         return err;
1776 }
1777
1778 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1779                                                      struct net_device *dev,
1780                                                      bool task_valid)
1781 {
1782         struct xfrm_policy *pol;
1783         int err = 0;
1784
1785         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1786                 if (pol->walk.dead ||
1787                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1788                     pol->xdo.dev != dev)
1789                         continue;
1790
1791                 err = security_xfrm_policy_delete(pol->security);
1792                 if (err) {
1793                         xfrm_audit_policy_delete(pol, 0, task_valid);
1794                         return err;
1795                 }
1796         }
1797         return err;
1798 }
1799 #else
1800 static inline int
1801 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1802 {
1803         return 0;
1804 }
1805
1806 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1807                                                      struct net_device *dev,
1808                                                      bool task_valid)
1809 {
1810         return 0;
1811 }
1812 #endif
1813
1814 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1815 {
1816         int dir, err = 0, cnt = 0;
1817         struct xfrm_policy *pol;
1818
1819         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1820
1821         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1822         if (err)
1823                 goto out;
1824
1825 again:
1826         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1827                 if (pol->walk.dead)
1828                         continue;
1829
1830                 dir = xfrm_policy_id2dir(pol->index);
1831                 if (dir >= XFRM_POLICY_MAX ||
1832                     pol->type != type)
1833                         continue;
1834
1835                 __xfrm_policy_unlink(pol, dir);
1836                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1837                 xfrm_dev_policy_delete(pol);
1838                 cnt++;
1839                 xfrm_audit_policy_delete(pol, 1, task_valid);
1840                 xfrm_policy_kill(pol);
1841                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1842                 goto again;
1843         }
1844         if (cnt)
1845                 __xfrm_policy_inexact_flush(net);
1846         else
1847                 err = -ESRCH;
1848 out:
1849         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1850         return err;
1851 }
1852 EXPORT_SYMBOL(xfrm_policy_flush);
1853
1854 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
1855                           bool task_valid)
1856 {
1857         int dir, err = 0, cnt = 0;
1858         struct xfrm_policy *pol;
1859
1860         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1861
1862         err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
1863         if (err)
1864                 goto out;
1865
1866 again:
1867         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1868                 if (pol->walk.dead)
1869                         continue;
1870
1871                 dir = xfrm_policy_id2dir(pol->index);
1872                 if (dir >= XFRM_POLICY_MAX ||
1873                     pol->xdo.dev != dev)
1874                         continue;
1875
1876                 __xfrm_policy_unlink(pol, dir);
1877                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1878                 xfrm_dev_policy_delete(pol);
1879                 cnt++;
1880                 xfrm_audit_policy_delete(pol, 1, task_valid);
1881                 xfrm_policy_kill(pol);
1882                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1883                 goto again;
1884         }
1885         if (cnt)
1886                 __xfrm_policy_inexact_flush(net);
1887         else
1888                 err = -ESRCH;
1889 out:
1890         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1891         return err;
1892 }
1893 EXPORT_SYMBOL(xfrm_dev_policy_flush);
1894
1895 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1896                      int (*func)(struct xfrm_policy *, int, int, void*),
1897                      void *data)
1898 {
1899         struct xfrm_policy *pol;
1900         struct xfrm_policy_walk_entry *x;
1901         int error = 0;
1902
1903         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1904             walk->type != XFRM_POLICY_TYPE_ANY)
1905                 return -EINVAL;
1906
1907         if (list_empty(&walk->walk.all) && walk->seq != 0)
1908                 return 0;
1909
1910         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1911         if (list_empty(&walk->walk.all))
1912                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1913         else
1914                 x = list_first_entry(&walk->walk.all,
1915                                      struct xfrm_policy_walk_entry, all);
1916
1917         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1918                 if (x->dead)
1919                         continue;
1920                 pol = container_of(x, struct xfrm_policy, walk);
1921                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1922                     walk->type != pol->type)
1923                         continue;
1924                 error = func(pol, xfrm_policy_id2dir(pol->index),
1925                              walk->seq, data);
1926                 if (error) {
1927                         list_move_tail(&walk->walk.all, &x->all);
1928                         goto out;
1929                 }
1930                 walk->seq++;
1931         }
1932         if (walk->seq == 0) {
1933                 error = -ENOENT;
1934                 goto out;
1935         }
1936         list_del_init(&walk->walk.all);
1937 out:
1938         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1939         return error;
1940 }
1941 EXPORT_SYMBOL(xfrm_policy_walk);
1942
1943 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1944 {
1945         INIT_LIST_HEAD(&walk->walk.all);
1946         walk->walk.dead = 1;
1947         walk->type = type;
1948         walk->seq = 0;
1949 }
1950 EXPORT_SYMBOL(xfrm_policy_walk_init);
1951
1952 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1953 {
1954         if (list_empty(&walk->walk.all))
1955                 return;
1956
1957         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1958         list_del(&walk->walk.all);
1959         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1960 }
1961 EXPORT_SYMBOL(xfrm_policy_walk_done);
1962
1963 /*
1964  * Find policy to apply to this flow.
1965  *
1966  * Returns 0 if policy found, else an -errno.
1967  */
1968 static int xfrm_policy_match(const struct xfrm_policy *pol,
1969                              const struct flowi *fl,
1970                              u8 type, u16 family, u32 if_id)
1971 {
1972         const struct xfrm_selector *sel = &pol->selector;
1973         int ret = -ESRCH;
1974         bool match;
1975
1976         if (pol->family != family ||
1977             pol->if_id != if_id ||
1978             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1979             pol->type != type)
1980                 return ret;
1981
1982         match = xfrm_selector_match(sel, fl, family);
1983         if (match)
1984                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
1985         return ret;
1986 }
1987
1988 static struct xfrm_pol_inexact_node *
1989 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1990                                 seqcount_spinlock_t *count,
1991                                 const xfrm_address_t *addr, u16 family)
1992 {
1993         const struct rb_node *parent;
1994         int seq;
1995
1996 again:
1997         seq = read_seqcount_begin(count);
1998
1999         parent = rcu_dereference_raw(r->rb_node);
2000         while (parent) {
2001                 struct xfrm_pol_inexact_node *node;
2002                 int delta;
2003
2004                 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
2005
2006                 delta = xfrm_policy_addr_delta(addr, &node->addr,
2007                                                node->prefixlen, family);
2008                 if (delta < 0) {
2009                         parent = rcu_dereference_raw(parent->rb_left);
2010                         continue;
2011                 } else if (delta > 0) {
2012                         parent = rcu_dereference_raw(parent->rb_right);
2013                         continue;
2014                 }
2015
2016                 return node;
2017         }
2018
2019         if (read_seqcount_retry(count, seq))
2020                 goto again;
2021
2022         return NULL;
2023 }
2024
2025 static bool
2026 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
2027                                     struct xfrm_pol_inexact_bin *b,
2028                                     const xfrm_address_t *saddr,
2029                                     const xfrm_address_t *daddr)
2030 {
2031         struct xfrm_pol_inexact_node *n;
2032         u16 family;
2033
2034         if (!b)
2035                 return false;
2036
2037         family = b->k.family;
2038         memset(cand, 0, sizeof(*cand));
2039         cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
2040
2041         n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
2042                                             family);
2043         if (n) {
2044                 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
2045                 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
2046                                                     family);
2047                 if (n)
2048                         cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
2049         }
2050
2051         n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
2052                                             family);
2053         if (n)
2054                 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
2055
2056         return true;
2057 }
2058
2059 static struct xfrm_pol_inexact_bin *
2060 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
2061                                u8 dir, u32 if_id)
2062 {
2063         struct xfrm_pol_inexact_key k = {
2064                 .family = family,
2065                 .type = type,
2066                 .dir = dir,
2067                 .if_id = if_id,
2068         };
2069
2070         write_pnet(&k.net, net);
2071
2072         return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
2073                                  xfrm_pol_inexact_params);
2074 }
2075
2076 static struct xfrm_pol_inexact_bin *
2077 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2078                            u8 dir, u32 if_id)
2079 {
2080         struct xfrm_pol_inexact_bin *bin;
2081
2082         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2083
2084         rcu_read_lock();
2085         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2086         rcu_read_unlock();
2087
2088         return bin;
2089 }
2090
2091 static struct xfrm_policy *
2092 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2093                               struct xfrm_policy *prefer,
2094                               const struct flowi *fl,
2095                               u8 type, u16 family, u32 if_id)
2096 {
2097         u32 priority = prefer ? prefer->priority : ~0u;
2098         struct xfrm_policy *pol;
2099
2100         if (!chain)
2101                 return NULL;
2102
2103         hlist_for_each_entry_rcu(pol, chain, bydst) {
2104                 int err;
2105
2106                 if (pol->priority > priority)
2107                         break;
2108
2109                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2110                 if (err) {
2111                         if (err != -ESRCH)
2112                                 return ERR_PTR(err);
2113
2114                         continue;
2115                 }
2116
2117                 if (prefer) {
2118                         /* matches.  Is it older than *prefer? */
2119                         if (pol->priority == priority &&
2120                             prefer->pos < pol->pos)
2121                                 return prefer;
2122                 }
2123
2124                 return pol;
2125         }
2126
2127         return NULL;
2128 }
2129
2130 static struct xfrm_policy *
2131 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2132                             struct xfrm_policy *prefer,
2133                             const struct flowi *fl,
2134                             u8 type, u16 family, u32 if_id)
2135 {
2136         struct xfrm_policy *tmp;
2137         int i;
2138
2139         for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2140                 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2141                                                     prefer,
2142                                                     fl, type, family, if_id);
2143                 if (!tmp)
2144                         continue;
2145
2146                 if (IS_ERR(tmp))
2147                         return tmp;
2148                 prefer = tmp;
2149         }
2150
2151         return prefer;
2152 }
2153
2154 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2155                                                      const struct flowi *fl,
2156                                                      u16 family, u8 dir,
2157                                                      u32 if_id)
2158 {
2159         struct xfrm_pol_inexact_candidates cand;
2160         const xfrm_address_t *daddr, *saddr;
2161         struct xfrm_pol_inexact_bin *bin;
2162         struct xfrm_policy *pol, *ret;
2163         struct hlist_head *chain;
2164         unsigned int sequence;
2165         int err;
2166
2167         daddr = xfrm_flowi_daddr(fl, family);
2168         saddr = xfrm_flowi_saddr(fl, family);
2169         if (unlikely(!daddr || !saddr))
2170                 return NULL;
2171
2172         rcu_read_lock();
2173  retry:
2174         do {
2175                 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2176                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2177         } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2178
2179         ret = NULL;
2180         hlist_for_each_entry_rcu(pol, chain, bydst) {
2181                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2182                 if (err) {
2183                         if (err == -ESRCH)
2184                                 continue;
2185                         else {
2186                                 ret = ERR_PTR(err);
2187                                 goto fail;
2188                         }
2189                 } else {
2190                         ret = pol;
2191                         break;
2192                 }
2193         }
2194         if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
2195                 goto skip_inexact;
2196
2197         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2198         if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2199                                                          daddr))
2200                 goto skip_inexact;
2201
2202         pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2203                                           family, if_id);
2204         if (pol) {
2205                 ret = pol;
2206                 if (IS_ERR(pol))
2207                         goto fail;
2208         }
2209
2210 skip_inexact:
2211         if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2212                 goto retry;
2213
2214         if (ret && !xfrm_pol_hold_rcu(ret))
2215                 goto retry;
2216 fail:
2217         rcu_read_unlock();
2218
2219         return ret;
2220 }
2221
2222 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2223                                               const struct flowi *fl,
2224                                               u16 family, u8 dir, u32 if_id)
2225 {
2226 #ifdef CONFIG_XFRM_SUB_POLICY
2227         struct xfrm_policy *pol;
2228
2229         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2230                                         dir, if_id);
2231         if (pol != NULL)
2232                 return pol;
2233 #endif
2234         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2235                                          dir, if_id);
2236 }
2237
2238 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2239                                                  const struct flowi *fl,
2240                                                  u16 family, u32 if_id)
2241 {
2242         struct xfrm_policy *pol;
2243
2244         rcu_read_lock();
2245  again:
2246         pol = rcu_dereference(sk->sk_policy[dir]);
2247         if (pol != NULL) {
2248                 bool match;
2249                 int err = 0;
2250
2251                 if (pol->family != family) {
2252                         pol = NULL;
2253                         goto out;
2254                 }
2255
2256                 match = xfrm_selector_match(&pol->selector, fl, family);
2257                 if (match) {
2258                         if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v ||
2259                             pol->if_id != if_id) {
2260                                 pol = NULL;
2261                                 goto out;
2262                         }
2263                         err = security_xfrm_policy_lookup(pol->security,
2264                                                       fl->flowi_secid);
2265                         if (!err) {
2266                                 if (!xfrm_pol_hold_rcu(pol))
2267                                         goto again;
2268                         } else if (err == -ESRCH) {
2269                                 pol = NULL;
2270                         } else {
2271                                 pol = ERR_PTR(err);
2272                         }
2273                 } else
2274                         pol = NULL;
2275         }
2276 out:
2277         rcu_read_unlock();
2278         return pol;
2279 }
2280
2281 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2282 {
2283         struct net *net = xp_net(pol);
2284
2285         list_add(&pol->walk.all, &net->xfrm.policy_all);
2286         net->xfrm.policy_count[dir]++;
2287         xfrm_pol_hold(pol);
2288 }
2289
2290 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2291                                                 int dir)
2292 {
2293         struct net *net = xp_net(pol);
2294
2295         if (list_empty(&pol->walk.all))
2296                 return NULL;
2297
2298         /* Socket policies are not hashed. */
2299         if (!hlist_unhashed(&pol->bydst)) {
2300                 hlist_del_rcu(&pol->bydst);
2301                 hlist_del_init(&pol->bydst_inexact_list);
2302                 hlist_del(&pol->byidx);
2303         }
2304
2305         list_del_init(&pol->walk.all);
2306         net->xfrm.policy_count[dir]--;
2307
2308         return pol;
2309 }
2310
2311 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2312 {
2313         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2314 }
2315
2316 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2317 {
2318         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2319 }
2320
2321 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2322 {
2323         struct net *net = xp_net(pol);
2324
2325         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2326         pol = __xfrm_policy_unlink(pol, dir);
2327         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2328         if (pol) {
2329                 xfrm_dev_policy_delete(pol);
2330                 xfrm_policy_kill(pol);
2331                 return 0;
2332         }
2333         return -ENOENT;
2334 }
2335 EXPORT_SYMBOL(xfrm_policy_delete);
2336
2337 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2338 {
2339         struct net *net = sock_net(sk);
2340         struct xfrm_policy *old_pol;
2341
2342 #ifdef CONFIG_XFRM_SUB_POLICY
2343         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2344                 return -EINVAL;
2345 #endif
2346
2347         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2348         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2349                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2350         if (pol) {
2351                 pol->curlft.add_time = ktime_get_real_seconds();
2352                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2353                 xfrm_sk_policy_link(pol, dir);
2354         }
2355         rcu_assign_pointer(sk->sk_policy[dir], pol);
2356         if (old_pol) {
2357                 if (pol)
2358                         xfrm_policy_requeue(old_pol, pol);
2359
2360                 /* Unlinking succeeds always. This is the only function
2361                  * allowed to delete or replace socket policy.
2362                  */
2363                 xfrm_sk_policy_unlink(old_pol, dir);
2364         }
2365         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2366
2367         if (old_pol) {
2368                 xfrm_policy_kill(old_pol);
2369         }
2370         return 0;
2371 }
2372
2373 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2374 {
2375         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2376         struct net *net = xp_net(old);
2377
2378         if (newp) {
2379                 newp->selector = old->selector;
2380                 if (security_xfrm_policy_clone(old->security,
2381                                                &newp->security)) {
2382                         kfree(newp);
2383                         return NULL;  /* ENOMEM */
2384                 }
2385                 newp->lft = old->lft;
2386                 newp->curlft = old->curlft;
2387                 newp->mark = old->mark;
2388                 newp->if_id = old->if_id;
2389                 newp->action = old->action;
2390                 newp->flags = old->flags;
2391                 newp->xfrm_nr = old->xfrm_nr;
2392                 newp->index = old->index;
2393                 newp->type = old->type;
2394                 newp->family = old->family;
2395                 memcpy(newp->xfrm_vec, old->xfrm_vec,
2396                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2397                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2398                 xfrm_sk_policy_link(newp, dir);
2399                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2400                 xfrm_pol_put(newp);
2401         }
2402         return newp;
2403 }
2404
2405 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2406 {
2407         const struct xfrm_policy *p;
2408         struct xfrm_policy *np;
2409         int i, ret = 0;
2410
2411         rcu_read_lock();
2412         for (i = 0; i < 2; i++) {
2413                 p = rcu_dereference(osk->sk_policy[i]);
2414                 if (p) {
2415                         np = clone_policy(p, i);
2416                         if (unlikely(!np)) {
2417                                 ret = -ENOMEM;
2418                                 break;
2419                         }
2420                         rcu_assign_pointer(sk->sk_policy[i], np);
2421                 }
2422         }
2423         rcu_read_unlock();
2424         return ret;
2425 }
2426
2427 static int
2428 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2429                xfrm_address_t *remote, unsigned short family, u32 mark)
2430 {
2431         int err;
2432         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2433
2434         if (unlikely(afinfo == NULL))
2435                 return -EINVAL;
2436         err = afinfo->get_saddr(net, oif, local, remote, mark);
2437         rcu_read_unlock();
2438         return err;
2439 }
2440
2441 /* Resolve list of templates for the flow, given policy. */
2442
2443 static int
2444 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2445                       struct xfrm_state **xfrm, unsigned short family)
2446 {
2447         struct net *net = xp_net(policy);
2448         int nx;
2449         int i, error;
2450         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2451         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2452         xfrm_address_t tmp;
2453
2454         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2455                 struct xfrm_state *x;
2456                 xfrm_address_t *remote = daddr;
2457                 xfrm_address_t *local  = saddr;
2458                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2459
2460                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2461                     tmpl->mode == XFRM_MODE_BEET) {
2462                         remote = &tmpl->id.daddr;
2463                         local = &tmpl->saddr;
2464                         if (xfrm_addr_any(local, tmpl->encap_family)) {
2465                                 error = xfrm_get_saddr(net, fl->flowi_oif,
2466                                                        &tmp, remote,
2467                                                        tmpl->encap_family, 0);
2468                                 if (error)
2469                                         goto fail;
2470                                 local = &tmp;
2471                         }
2472                 }
2473
2474                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2475                                     family, policy->if_id);
2476
2477                 if (x && x->km.state == XFRM_STATE_VALID) {
2478                         xfrm[nx++] = x;
2479                         daddr = remote;
2480                         saddr = local;
2481                         continue;
2482                 }
2483                 if (x) {
2484                         error = (x->km.state == XFRM_STATE_ERROR ?
2485                                  -EINVAL : -EAGAIN);
2486                         xfrm_state_put(x);
2487                 } else if (error == -ESRCH) {
2488                         error = -EAGAIN;
2489                 }
2490
2491                 if (!tmpl->optional)
2492                         goto fail;
2493         }
2494         return nx;
2495
2496 fail:
2497         for (nx--; nx >= 0; nx--)
2498                 xfrm_state_put(xfrm[nx]);
2499         return error;
2500 }
2501
2502 static int
2503 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2504                   struct xfrm_state **xfrm, unsigned short family)
2505 {
2506         struct xfrm_state *tp[XFRM_MAX_DEPTH];
2507         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2508         int cnx = 0;
2509         int error;
2510         int ret;
2511         int i;
2512
2513         for (i = 0; i < npols; i++) {
2514                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2515                         error = -ENOBUFS;
2516                         goto fail;
2517                 }
2518
2519                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2520                 if (ret < 0) {
2521                         error = ret;
2522                         goto fail;
2523                 } else
2524                         cnx += ret;
2525         }
2526
2527         /* found states are sorted for outbound processing */
2528         if (npols > 1)
2529                 xfrm_state_sort(xfrm, tpp, cnx, family);
2530
2531         return cnx;
2532
2533  fail:
2534         for (cnx--; cnx >= 0; cnx--)
2535                 xfrm_state_put(tpp[cnx]);
2536         return error;
2537
2538 }
2539
2540 static int xfrm_get_tos(const struct flowi *fl, int family)
2541 {
2542         if (family == AF_INET)
2543                 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2544
2545         return 0;
2546 }
2547
2548 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2549 {
2550         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2551         struct dst_ops *dst_ops;
2552         struct xfrm_dst *xdst;
2553
2554         if (!afinfo)
2555                 return ERR_PTR(-EINVAL);
2556
2557         switch (family) {
2558         case AF_INET:
2559                 dst_ops = &net->xfrm.xfrm4_dst_ops;
2560                 break;
2561 #if IS_ENABLED(CONFIG_IPV6)
2562         case AF_INET6:
2563                 dst_ops = &net->xfrm.xfrm6_dst_ops;
2564                 break;
2565 #endif
2566         default:
2567                 BUG();
2568         }
2569         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2570
2571         if (likely(xdst)) {
2572                 memset_after(xdst, 0, u.dst);
2573         } else
2574                 xdst = ERR_PTR(-ENOBUFS);
2575
2576         rcu_read_unlock();
2577
2578         return xdst;
2579 }
2580
2581 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2582                            int nfheader_len)
2583 {
2584         if (dst->ops->family == AF_INET6) {
2585                 struct rt6_info *rt = (struct rt6_info *)dst;
2586                 path->path_cookie = rt6_get_cookie(rt);
2587                 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2588         }
2589 }
2590
2591 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2592                                 const struct flowi *fl)
2593 {
2594         const struct xfrm_policy_afinfo *afinfo =
2595                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2596         int err;
2597
2598         if (!afinfo)
2599                 return -EINVAL;
2600
2601         err = afinfo->fill_dst(xdst, dev, fl);
2602
2603         rcu_read_unlock();
2604
2605         return err;
2606 }
2607
2608
2609 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2610  * all the metrics... Shortly, bundle a bundle.
2611  */
2612
2613 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2614                                             struct xfrm_state **xfrm,
2615                                             struct xfrm_dst **bundle,
2616                                             int nx,
2617                                             const struct flowi *fl,
2618                                             struct dst_entry *dst)
2619 {
2620         const struct xfrm_state_afinfo *afinfo;
2621         const struct xfrm_mode *inner_mode;
2622         struct net *net = xp_net(policy);
2623         unsigned long now = jiffies;
2624         struct net_device *dev;
2625         struct xfrm_dst *xdst_prev = NULL;
2626         struct xfrm_dst *xdst0 = NULL;
2627         int i = 0;
2628         int err;
2629         int header_len = 0;
2630         int nfheader_len = 0;
2631         int trailer_len = 0;
2632         int tos;
2633         int family = policy->selector.family;
2634         xfrm_address_t saddr, daddr;
2635
2636         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2637
2638         tos = xfrm_get_tos(fl, family);
2639
2640         dst_hold(dst);
2641
2642         for (; i < nx; i++) {
2643                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2644                 struct dst_entry *dst1 = &xdst->u.dst;
2645
2646                 err = PTR_ERR(xdst);
2647                 if (IS_ERR(xdst)) {
2648                         dst_release(dst);
2649                         goto put_states;
2650                 }
2651
2652                 bundle[i] = xdst;
2653                 if (!xdst_prev)
2654                         xdst0 = xdst;
2655                 else
2656                         /* Ref count is taken during xfrm_alloc_dst()
2657                          * No need to do dst_clone() on dst1
2658                          */
2659                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2660
2661                 if (xfrm[i]->sel.family == AF_UNSPEC) {
2662                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
2663                                                         xfrm_af2proto(family));
2664                         if (!inner_mode) {
2665                                 err = -EAFNOSUPPORT;
2666                                 dst_release(dst);
2667                                 goto put_states;
2668                         }
2669                 } else
2670                         inner_mode = &xfrm[i]->inner_mode;
2671
2672                 xdst->route = dst;
2673                 dst_copy_metrics(dst1, dst);
2674
2675                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2676                         __u32 mark = 0;
2677                         int oif;
2678
2679                         if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2680                                 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2681
2682                         family = xfrm[i]->props.family;
2683                         oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2684                         dst = xfrm_dst_lookup(xfrm[i], tos, oif,
2685                                               &saddr, &daddr, family, mark);
2686                         err = PTR_ERR(dst);
2687                         if (IS_ERR(dst))
2688                                 goto put_states;
2689                 } else
2690                         dst_hold(dst);
2691
2692                 dst1->xfrm = xfrm[i];
2693                 xdst->xfrm_genid = xfrm[i]->genid;
2694
2695                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2696                 dst1->lastuse = now;
2697
2698                 dst1->input = dst_discard;
2699
2700                 rcu_read_lock();
2701                 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2702                 if (likely(afinfo))
2703                         dst1->output = afinfo->output;
2704                 else
2705                         dst1->output = dst_discard_out;
2706                 rcu_read_unlock();
2707
2708                 xdst_prev = xdst;
2709
2710                 header_len += xfrm[i]->props.header_len;
2711                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2712                         nfheader_len += xfrm[i]->props.header_len;
2713                 trailer_len += xfrm[i]->props.trailer_len;
2714         }
2715
2716         xfrm_dst_set_child(xdst_prev, dst);
2717         xdst0->path = dst;
2718
2719         err = -ENODEV;
2720         dev = dst->dev;
2721         if (!dev)
2722                 goto free_dst;
2723
2724         xfrm_init_path(xdst0, dst, nfheader_len);
2725         xfrm_init_pmtu(bundle, nx);
2726
2727         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2728              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2729                 err = xfrm_fill_dst(xdst_prev, dev, fl);
2730                 if (err)
2731                         goto free_dst;
2732
2733                 xdst_prev->u.dst.header_len = header_len;
2734                 xdst_prev->u.dst.trailer_len = trailer_len;
2735                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2736                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2737         }
2738
2739         return &xdst0->u.dst;
2740
2741 put_states:
2742         for (; i < nx; i++)
2743                 xfrm_state_put(xfrm[i]);
2744 free_dst:
2745         if (xdst0)
2746                 dst_release_immediate(&xdst0->u.dst);
2747
2748         return ERR_PTR(err);
2749 }
2750
2751 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2752                                 struct xfrm_policy **pols,
2753                                 int *num_pols, int *num_xfrms)
2754 {
2755         int i;
2756
2757         if (*num_pols == 0 || !pols[0]) {
2758                 *num_pols = 0;
2759                 *num_xfrms = 0;
2760                 return 0;
2761         }
2762         if (IS_ERR(pols[0])) {
2763                 *num_pols = 0;
2764                 return PTR_ERR(pols[0]);
2765         }
2766
2767         *num_xfrms = pols[0]->xfrm_nr;
2768
2769 #ifdef CONFIG_XFRM_SUB_POLICY
2770         if (pols[0]->action == XFRM_POLICY_ALLOW &&
2771             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2772                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2773                                                     XFRM_POLICY_TYPE_MAIN,
2774                                                     fl, family,
2775                                                     XFRM_POLICY_OUT,
2776                                                     pols[0]->if_id);
2777                 if (pols[1]) {
2778                         if (IS_ERR(pols[1])) {
2779                                 xfrm_pols_put(pols, *num_pols);
2780                                 *num_pols = 0;
2781                                 return PTR_ERR(pols[1]);
2782                         }
2783                         (*num_pols)++;
2784                         (*num_xfrms) += pols[1]->xfrm_nr;
2785                 }
2786         }
2787 #endif
2788         for (i = 0; i < *num_pols; i++) {
2789                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2790                         *num_xfrms = -1;
2791                         break;
2792                 }
2793         }
2794
2795         return 0;
2796
2797 }
2798
2799 static struct xfrm_dst *
2800 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2801                                const struct flowi *fl, u16 family,
2802                                struct dst_entry *dst_orig)
2803 {
2804         struct net *net = xp_net(pols[0]);
2805         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2806         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2807         struct xfrm_dst *xdst;
2808         struct dst_entry *dst;
2809         int err;
2810
2811         /* Try to instantiate a bundle */
2812         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2813         if (err <= 0) {
2814                 if (err == 0)
2815                         return NULL;
2816
2817                 if (err != -EAGAIN)
2818                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2819                 return ERR_PTR(err);
2820         }
2821
2822         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2823         if (IS_ERR(dst)) {
2824                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2825                 return ERR_CAST(dst);
2826         }
2827
2828         xdst = (struct xfrm_dst *)dst;
2829         xdst->num_xfrms = err;
2830         xdst->num_pols = num_pols;
2831         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2832         xdst->policy_genid = atomic_read(&pols[0]->genid);
2833
2834         return xdst;
2835 }
2836
2837 static void xfrm_policy_queue_process(struct timer_list *t)
2838 {
2839         struct sk_buff *skb;
2840         struct sock *sk;
2841         struct dst_entry *dst;
2842         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2843         struct net *net = xp_net(pol);
2844         struct xfrm_policy_queue *pq = &pol->polq;
2845         struct flowi fl;
2846         struct sk_buff_head list;
2847         __u32 skb_mark;
2848
2849         spin_lock(&pq->hold_queue.lock);
2850         skb = skb_peek(&pq->hold_queue);
2851         if (!skb) {
2852                 spin_unlock(&pq->hold_queue.lock);
2853                 goto out;
2854         }
2855         dst = skb_dst(skb);
2856         sk = skb->sk;
2857
2858         /* Fixup the mark to support VTI. */
2859         skb_mark = skb->mark;
2860         skb->mark = pol->mark.v;
2861         xfrm_decode_session(skb, &fl, dst->ops->family);
2862         skb->mark = skb_mark;
2863         spin_unlock(&pq->hold_queue.lock);
2864
2865         dst_hold(xfrm_dst_path(dst));
2866         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2867         if (IS_ERR(dst))
2868                 goto purge_queue;
2869
2870         if (dst->flags & DST_XFRM_QUEUE) {
2871                 dst_release(dst);
2872
2873                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2874                         goto purge_queue;
2875
2876                 pq->timeout = pq->timeout << 1;
2877                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2878                         xfrm_pol_hold(pol);
2879                 goto out;
2880         }
2881
2882         dst_release(dst);
2883
2884         __skb_queue_head_init(&list);
2885
2886         spin_lock(&pq->hold_queue.lock);
2887         pq->timeout = 0;
2888         skb_queue_splice_init(&pq->hold_queue, &list);
2889         spin_unlock(&pq->hold_queue.lock);
2890
2891         while (!skb_queue_empty(&list)) {
2892                 skb = __skb_dequeue(&list);
2893
2894                 /* Fixup the mark to support VTI. */
2895                 skb_mark = skb->mark;
2896                 skb->mark = pol->mark.v;
2897                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2898                 skb->mark = skb_mark;
2899
2900                 dst_hold(xfrm_dst_path(skb_dst(skb)));
2901                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2902                 if (IS_ERR(dst)) {
2903                         kfree_skb(skb);
2904                         continue;
2905                 }
2906
2907                 nf_reset_ct(skb);
2908                 skb_dst_drop(skb);
2909                 skb_dst_set(skb, dst);
2910
2911                 dst_output(net, skb->sk, skb);
2912         }
2913
2914 out:
2915         xfrm_pol_put(pol);
2916         return;
2917
2918 purge_queue:
2919         pq->timeout = 0;
2920         skb_queue_purge(&pq->hold_queue);
2921         xfrm_pol_put(pol);
2922 }
2923
2924 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2925 {
2926         unsigned long sched_next;
2927         struct dst_entry *dst = skb_dst(skb);
2928         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2929         struct xfrm_policy *pol = xdst->pols[0];
2930         struct xfrm_policy_queue *pq = &pol->polq;
2931
2932         if (unlikely(skb_fclone_busy(sk, skb))) {
2933                 kfree_skb(skb);
2934                 return 0;
2935         }
2936
2937         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2938                 kfree_skb(skb);
2939                 return -EAGAIN;
2940         }
2941
2942         skb_dst_force(skb);
2943
2944         spin_lock_bh(&pq->hold_queue.lock);
2945
2946         if (!pq->timeout)
2947                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2948
2949         sched_next = jiffies + pq->timeout;
2950
2951         if (del_timer(&pq->hold_timer)) {
2952                 if (time_before(pq->hold_timer.expires, sched_next))
2953                         sched_next = pq->hold_timer.expires;
2954                 xfrm_pol_put(pol);
2955         }
2956
2957         __skb_queue_tail(&pq->hold_queue, skb);
2958         if (!mod_timer(&pq->hold_timer, sched_next))
2959                 xfrm_pol_hold(pol);
2960
2961         spin_unlock_bh(&pq->hold_queue.lock);
2962
2963         return 0;
2964 }
2965
2966 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2967                                                  struct xfrm_flo *xflo,
2968                                                  const struct flowi *fl,
2969                                                  int num_xfrms,
2970                                                  u16 family)
2971 {
2972         int err;
2973         struct net_device *dev;
2974         struct dst_entry *dst;
2975         struct dst_entry *dst1;
2976         struct xfrm_dst *xdst;
2977
2978         xdst = xfrm_alloc_dst(net, family);
2979         if (IS_ERR(xdst))
2980                 return xdst;
2981
2982         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2983             net->xfrm.sysctl_larval_drop ||
2984             num_xfrms <= 0)
2985                 return xdst;
2986
2987         dst = xflo->dst_orig;
2988         dst1 = &xdst->u.dst;
2989         dst_hold(dst);
2990         xdst->route = dst;
2991
2992         dst_copy_metrics(dst1, dst);
2993
2994         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2995         dst1->flags |= DST_XFRM_QUEUE;
2996         dst1->lastuse = jiffies;
2997
2998         dst1->input = dst_discard;
2999         dst1->output = xdst_queue_output;
3000
3001         dst_hold(dst);
3002         xfrm_dst_set_child(xdst, dst);
3003         xdst->path = dst;
3004
3005         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
3006
3007         err = -ENODEV;
3008         dev = dst->dev;
3009         if (!dev)
3010                 goto free_dst;
3011
3012         err = xfrm_fill_dst(xdst, dev, fl);
3013         if (err)
3014                 goto free_dst;
3015
3016 out:
3017         return xdst;
3018
3019 free_dst:
3020         dst_release(dst1);
3021         xdst = ERR_PTR(err);
3022         goto out;
3023 }
3024
3025 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
3026                                            const struct flowi *fl,
3027                                            u16 family, u8 dir,
3028                                            struct xfrm_flo *xflo, u32 if_id)
3029 {
3030         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3031         int num_pols = 0, num_xfrms = 0, err;
3032         struct xfrm_dst *xdst;
3033
3034         /* Resolve policies to use if we couldn't get them from
3035          * previous cache entry */
3036         num_pols = 1;
3037         pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
3038         err = xfrm_expand_policies(fl, family, pols,
3039                                            &num_pols, &num_xfrms);
3040         if (err < 0)
3041                 goto inc_error;
3042         if (num_pols == 0)
3043                 return NULL;
3044         if (num_xfrms <= 0)
3045                 goto make_dummy_bundle;
3046
3047         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
3048                                               xflo->dst_orig);
3049         if (IS_ERR(xdst)) {
3050                 err = PTR_ERR(xdst);
3051                 if (err == -EREMOTE) {
3052                         xfrm_pols_put(pols, num_pols);
3053                         return NULL;
3054                 }
3055
3056                 if (err != -EAGAIN)
3057                         goto error;
3058                 goto make_dummy_bundle;
3059         } else if (xdst == NULL) {
3060                 num_xfrms = 0;
3061                 goto make_dummy_bundle;
3062         }
3063
3064         return xdst;
3065
3066 make_dummy_bundle:
3067         /* We found policies, but there's no bundles to instantiate:
3068          * either because the policy blocks, has no transformations or
3069          * we could not build template (no xfrm_states).*/
3070         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
3071         if (IS_ERR(xdst)) {
3072                 xfrm_pols_put(pols, num_pols);
3073                 return ERR_CAST(xdst);
3074         }
3075         xdst->num_pols = num_pols;
3076         xdst->num_xfrms = num_xfrms;
3077         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
3078
3079         return xdst;
3080
3081 inc_error:
3082         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3083 error:
3084         xfrm_pols_put(pols, num_pols);
3085         return ERR_PTR(err);
3086 }
3087
3088 static struct dst_entry *make_blackhole(struct net *net, u16 family,
3089                                         struct dst_entry *dst_orig)
3090 {
3091         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3092         struct dst_entry *ret;
3093
3094         if (!afinfo) {
3095                 dst_release(dst_orig);
3096                 return ERR_PTR(-EINVAL);
3097         } else {
3098                 ret = afinfo->blackhole_route(net, dst_orig);
3099         }
3100         rcu_read_unlock();
3101
3102         return ret;
3103 }
3104
3105 /* Finds/creates a bundle for given flow and if_id
3106  *
3107  * At the moment we eat a raw IP route. Mostly to speed up lookups
3108  * on interfaces with disabled IPsec.
3109  *
3110  * xfrm_lookup uses an if_id of 0 by default, and is provided for
3111  * compatibility
3112  */
3113 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3114                                         struct dst_entry *dst_orig,
3115                                         const struct flowi *fl,
3116                                         const struct sock *sk,
3117                                         int flags, u32 if_id)
3118 {
3119         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3120         struct xfrm_dst *xdst;
3121         struct dst_entry *dst, *route;
3122         u16 family = dst_orig->ops->family;
3123         u8 dir = XFRM_POLICY_OUT;
3124         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3125
3126         dst = NULL;
3127         xdst = NULL;
3128         route = NULL;
3129
3130         sk = sk_const_to_full_sk(sk);
3131         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3132                 num_pols = 1;
3133                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3134                                                 if_id);
3135                 err = xfrm_expand_policies(fl, family, pols,
3136                                            &num_pols, &num_xfrms);
3137                 if (err < 0)
3138                         goto dropdst;
3139
3140                 if (num_pols) {
3141                         if (num_xfrms <= 0) {
3142                                 drop_pols = num_pols;
3143                                 goto no_transform;
3144                         }
3145
3146                         xdst = xfrm_resolve_and_create_bundle(
3147                                         pols, num_pols, fl,
3148                                         family, dst_orig);
3149
3150                         if (IS_ERR(xdst)) {
3151                                 xfrm_pols_put(pols, num_pols);
3152                                 err = PTR_ERR(xdst);
3153                                 if (err == -EREMOTE)
3154                                         goto nopol;
3155
3156                                 goto dropdst;
3157                         } else if (xdst == NULL) {
3158                                 num_xfrms = 0;
3159                                 drop_pols = num_pols;
3160                                 goto no_transform;
3161                         }
3162
3163                         route = xdst->route;
3164                 }
3165         }
3166
3167         if (xdst == NULL) {
3168                 struct xfrm_flo xflo;
3169
3170                 xflo.dst_orig = dst_orig;
3171                 xflo.flags = flags;
3172
3173                 /* To accelerate a bit...  */
3174                 if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3175                                !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3176                         goto nopol;
3177
3178                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3179                 if (xdst == NULL)
3180                         goto nopol;
3181                 if (IS_ERR(xdst)) {
3182                         err = PTR_ERR(xdst);
3183                         goto dropdst;
3184                 }
3185
3186                 num_pols = xdst->num_pols;
3187                 num_xfrms = xdst->num_xfrms;
3188                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3189                 route = xdst->route;
3190         }
3191
3192         dst = &xdst->u.dst;
3193         if (route == NULL && num_xfrms > 0) {
3194                 /* The only case when xfrm_bundle_lookup() returns a
3195                  * bundle with null route, is when the template could
3196                  * not be resolved. It means policies are there, but
3197                  * bundle could not be created, since we don't yet
3198                  * have the xfrm_state's. We need to wait for KM to
3199                  * negotiate new SA's or bail out with error.*/
3200                 if (net->xfrm.sysctl_larval_drop) {
3201                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3202                         err = -EREMOTE;
3203                         goto error;
3204                 }
3205
3206                 err = -EAGAIN;
3207
3208                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3209                 goto error;
3210         }
3211
3212 no_transform:
3213         if (num_pols == 0)
3214                 goto nopol;
3215
3216         if ((flags & XFRM_LOOKUP_ICMP) &&
3217             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3218                 err = -ENOENT;
3219                 goto error;
3220         }
3221
3222         for (i = 0; i < num_pols; i++)
3223                 WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds());
3224
3225         if (num_xfrms < 0) {
3226                 /* Prohibit the flow */
3227                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3228                 err = -EPERM;
3229                 goto error;
3230         } else if (num_xfrms > 0) {
3231                 /* Flow transformed */
3232                 dst_release(dst_orig);
3233         } else {
3234                 /* Flow passes untransformed */
3235                 dst_release(dst);
3236                 dst = dst_orig;
3237         }
3238 ok:
3239         xfrm_pols_put(pols, drop_pols);
3240         if (dst && dst->xfrm &&
3241             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3242                 dst->flags |= DST_XFRM_TUNNEL;
3243         return dst;
3244
3245 nopol:
3246         if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3247             net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3248                 err = -EPERM;
3249                 goto error;
3250         }
3251         if (!(flags & XFRM_LOOKUP_ICMP)) {
3252                 dst = dst_orig;
3253                 goto ok;
3254         }
3255         err = -ENOENT;
3256 error:
3257         dst_release(dst);
3258 dropdst:
3259         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3260                 dst_release(dst_orig);
3261         xfrm_pols_put(pols, drop_pols);
3262         return ERR_PTR(err);
3263 }
3264 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3265
3266 /* Main function: finds/creates a bundle for given flow.
3267  *
3268  * At the moment we eat a raw IP route. Mostly to speed up lookups
3269  * on interfaces with disabled IPsec.
3270  */
3271 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3272                               const struct flowi *fl, const struct sock *sk,
3273                               int flags)
3274 {
3275         return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3276 }
3277 EXPORT_SYMBOL(xfrm_lookup);
3278
3279 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3280  * Otherwise we may send out blackholed packets.
3281  */
3282 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3283                                     const struct flowi *fl,
3284                                     const struct sock *sk, int flags)
3285 {
3286         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3287                                             flags | XFRM_LOOKUP_QUEUE |
3288                                             XFRM_LOOKUP_KEEP_DST_REF);
3289
3290         if (PTR_ERR(dst) == -EREMOTE)
3291                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3292
3293         if (IS_ERR(dst))
3294                 dst_release(dst_orig);
3295
3296         return dst;
3297 }
3298 EXPORT_SYMBOL(xfrm_lookup_route);
3299
3300 static inline int
3301 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3302 {
3303         struct sec_path *sp = skb_sec_path(skb);
3304         struct xfrm_state *x;
3305
3306         if (!sp || idx < 0 || idx >= sp->len)
3307                 return 0;
3308         x = sp->xvec[idx];
3309         if (!x->type->reject)
3310                 return 0;
3311         return x->type->reject(x, skb, fl);
3312 }
3313
3314 /* When skb is transformed back to its "native" form, we have to
3315  * check policy restrictions. At the moment we make this in maximally
3316  * stupid way. Shame on me. :-) Of course, connected sockets must
3317  * have policy cached at them.
3318  */
3319
3320 static inline int
3321 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3322               unsigned short family, u32 if_id)
3323 {
3324         if (xfrm_state_kern(x))
3325                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3326         return  x->id.proto == tmpl->id.proto &&
3327                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3328                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3329                 x->props.mode == tmpl->mode &&
3330                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3331                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3332                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3333                   xfrm_state_addr_cmp(tmpl, x, family)) &&
3334                 (if_id == 0 || if_id == x->if_id);
3335 }
3336
3337 /*
3338  * 0 or more than 0 is returned when validation is succeeded (either bypass
3339  * because of optional transport mode, or next index of the matched secpath
3340  * state with the template.
3341  * -1 is returned when no matching template is found.
3342  * Otherwise "-2 - errored_index" is returned.
3343  */
3344 static inline int
3345 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3346                unsigned short family, u32 if_id)
3347 {
3348         int idx = start;
3349
3350         if (tmpl->optional) {
3351                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3352                         return start;
3353         } else
3354                 start = -1;
3355         for (; idx < sp->len; idx++) {
3356                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
3357                         return ++idx;
3358                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3359                         if (idx < sp->verified_cnt) {
3360                                 /* Secpath entry previously verified, consider optional and
3361                                  * continue searching
3362                                  */
3363                                 continue;
3364                         }
3365
3366                         if (start == -1)
3367                                 start = -2-idx;
3368                         break;
3369                 }
3370         }
3371         return start;
3372 }
3373
3374 static void
3375 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3376 {
3377         const struct iphdr *iph = ip_hdr(skb);
3378         int ihl = iph->ihl;
3379         u8 *xprth = skb_network_header(skb) + ihl * 4;
3380         struct flowi4 *fl4 = &fl->u.ip4;
3381         int oif = 0;
3382
3383         if (skb_dst(skb) && skb_dst(skb)->dev)
3384                 oif = skb_dst(skb)->dev->ifindex;
3385
3386         memset(fl4, 0, sizeof(struct flowi4));
3387         fl4->flowi4_mark = skb->mark;
3388         fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3389
3390         fl4->flowi4_proto = iph->protocol;
3391         fl4->daddr = reverse ? iph->saddr : iph->daddr;
3392         fl4->saddr = reverse ? iph->daddr : iph->saddr;
3393         fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK;
3394
3395         if (!ip_is_fragment(iph)) {
3396                 switch (iph->protocol) {
3397                 case IPPROTO_UDP:
3398                 case IPPROTO_UDPLITE:
3399                 case IPPROTO_TCP:
3400                 case IPPROTO_SCTP:
3401                 case IPPROTO_DCCP:
3402                         if (xprth + 4 < skb->data ||
3403                             pskb_may_pull(skb, xprth + 4 - skb->data)) {
3404                                 __be16 *ports;
3405
3406                                 xprth = skb_network_header(skb) + ihl * 4;
3407                                 ports = (__be16 *)xprth;
3408
3409                                 fl4->fl4_sport = ports[!!reverse];
3410                                 fl4->fl4_dport = ports[!reverse];
3411                         }
3412                         break;
3413                 case IPPROTO_ICMP:
3414                         if (xprth + 2 < skb->data ||
3415                             pskb_may_pull(skb, xprth + 2 - skb->data)) {
3416                                 u8 *icmp;
3417
3418                                 xprth = skb_network_header(skb) + ihl * 4;
3419                                 icmp = xprth;
3420
3421                                 fl4->fl4_icmp_type = icmp[0];
3422                                 fl4->fl4_icmp_code = icmp[1];
3423                         }
3424                         break;
3425                 case IPPROTO_GRE:
3426                         if (xprth + 12 < skb->data ||
3427                             pskb_may_pull(skb, xprth + 12 - skb->data)) {
3428                                 __be16 *greflags;
3429                                 __be32 *gre_hdr;
3430
3431                                 xprth = skb_network_header(skb) + ihl * 4;
3432                                 greflags = (__be16 *)xprth;
3433                                 gre_hdr = (__be32 *)xprth;
3434
3435                                 if (greflags[0] & GRE_KEY) {
3436                                         if (greflags[0] & GRE_CSUM)
3437                                                 gre_hdr++;
3438                                         fl4->fl4_gre_key = gre_hdr[1];
3439                                 }
3440                         }
3441                         break;
3442                 default:
3443                         break;
3444                 }
3445         }
3446 }
3447
3448 #if IS_ENABLED(CONFIG_IPV6)
3449 static void
3450 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3451 {
3452         struct flowi6 *fl6 = &fl->u.ip6;
3453         int onlyproto = 0;
3454         const struct ipv6hdr *hdr = ipv6_hdr(skb);
3455         u32 offset = sizeof(*hdr);
3456         struct ipv6_opt_hdr *exthdr;
3457         const unsigned char *nh = skb_network_header(skb);
3458         u16 nhoff = IP6CB(skb)->nhoff;
3459         int oif = 0;
3460         u8 nexthdr;
3461
3462         if (!nhoff)
3463                 nhoff = offsetof(struct ipv6hdr, nexthdr);
3464
3465         nexthdr = nh[nhoff];
3466
3467         if (skb_dst(skb) && skb_dst(skb)->dev)
3468                 oif = skb_dst(skb)->dev->ifindex;
3469
3470         memset(fl6, 0, sizeof(struct flowi6));
3471         fl6->flowi6_mark = skb->mark;
3472         fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3473
3474         fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3475         fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3476
3477         while (nh + offset + sizeof(*exthdr) < skb->data ||
3478                pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3479                 nh = skb_network_header(skb);
3480                 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3481
3482                 switch (nexthdr) {
3483                 case NEXTHDR_FRAGMENT:
3484                         onlyproto = 1;
3485                         fallthrough;
3486                 case NEXTHDR_ROUTING:
3487                 case NEXTHDR_HOP:
3488                 case NEXTHDR_DEST:
3489                         offset += ipv6_optlen(exthdr);
3490                         nexthdr = exthdr->nexthdr;
3491                         break;
3492                 case IPPROTO_UDP:
3493                 case IPPROTO_UDPLITE:
3494                 case IPPROTO_TCP:
3495                 case IPPROTO_SCTP:
3496                 case IPPROTO_DCCP:
3497                         if (!onlyproto && (nh + offset + 4 < skb->data ||
3498                              pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3499                                 __be16 *ports;
3500
3501                                 nh = skb_network_header(skb);
3502                                 ports = (__be16 *)(nh + offset);
3503                                 fl6->fl6_sport = ports[!!reverse];
3504                                 fl6->fl6_dport = ports[!reverse];
3505                         }
3506                         fl6->flowi6_proto = nexthdr;
3507                         return;
3508                 case IPPROTO_ICMPV6:
3509                         if (!onlyproto && (nh + offset + 2 < skb->data ||
3510                             pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3511                                 u8 *icmp;
3512
3513                                 nh = skb_network_header(skb);
3514                                 icmp = (u8 *)(nh + offset);
3515                                 fl6->fl6_icmp_type = icmp[0];
3516                                 fl6->fl6_icmp_code = icmp[1];
3517                         }
3518                         fl6->flowi6_proto = nexthdr;
3519                         return;
3520                 case IPPROTO_GRE:
3521                         if (!onlyproto &&
3522                             (nh + offset + 12 < skb->data ||
3523                              pskb_may_pull(skb, nh + offset + 12 - skb->data))) {
3524                                 struct gre_base_hdr *gre_hdr;
3525                                 __be32 *gre_key;
3526
3527                                 nh = skb_network_header(skb);
3528                                 gre_hdr = (struct gre_base_hdr *)(nh + offset);
3529                                 gre_key = (__be32 *)(gre_hdr + 1);
3530
3531                                 if (gre_hdr->flags & GRE_KEY) {
3532                                         if (gre_hdr->flags & GRE_CSUM)
3533                                                 gre_key++;
3534                                         fl6->fl6_gre_key = *gre_key;
3535                                 }
3536                         }
3537                         fl6->flowi6_proto = nexthdr;
3538                         return;
3539
3540 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3541                 case IPPROTO_MH:
3542                         offset += ipv6_optlen(exthdr);
3543                         if (!onlyproto && (nh + offset + 3 < skb->data ||
3544                             pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3545                                 struct ip6_mh *mh;
3546
3547                                 nh = skb_network_header(skb);
3548                                 mh = (struct ip6_mh *)(nh + offset);
3549                                 fl6->fl6_mh_type = mh->ip6mh_type;
3550                         }
3551                         fl6->flowi6_proto = nexthdr;
3552                         return;
3553 #endif
3554                 default:
3555                         fl6->flowi6_proto = nexthdr;
3556                         return;
3557                 }
3558         }
3559 }
3560 #endif
3561
3562 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3563                           unsigned int family, int reverse)
3564 {
3565         switch (family) {
3566         case AF_INET:
3567                 decode_session4(skb, fl, reverse);
3568                 break;
3569 #if IS_ENABLED(CONFIG_IPV6)
3570         case AF_INET6:
3571                 decode_session6(skb, fl, reverse);
3572                 break;
3573 #endif
3574         default:
3575                 return -EAFNOSUPPORT;
3576         }
3577
3578         return security_xfrm_decode_session(skb, &fl->flowi_secid);
3579 }
3580 EXPORT_SYMBOL(__xfrm_decode_session);
3581
3582 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3583 {
3584         for (; k < sp->len; k++) {
3585                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3586                         *idxp = k;
3587                         return 1;
3588                 }
3589         }
3590
3591         return 0;
3592 }
3593
3594 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3595                         unsigned short family)
3596 {
3597         struct net *net = dev_net(skb->dev);
3598         struct xfrm_policy *pol;
3599         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3600         int npols = 0;
3601         int xfrm_nr;
3602         int pi;
3603         int reverse;
3604         struct flowi fl;
3605         int xerr_idx = -1;
3606         const struct xfrm_if_cb *ifcb;
3607         struct sec_path *sp;
3608         u32 if_id = 0;
3609
3610         rcu_read_lock();
3611         ifcb = xfrm_if_get_cb();
3612
3613         if (ifcb) {
3614                 struct xfrm_if_decode_session_result r;
3615
3616                 if (ifcb->decode_session(skb, family, &r)) {
3617                         if_id = r.if_id;
3618                         net = r.net;
3619                 }
3620         }
3621         rcu_read_unlock();
3622
3623         reverse = dir & ~XFRM_POLICY_MASK;
3624         dir &= XFRM_POLICY_MASK;
3625
3626         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3627                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3628                 return 0;
3629         }
3630
3631         nf_nat_decode_session(skb, &fl, family);
3632
3633         /* First, check used SA against their selectors. */
3634         sp = skb_sec_path(skb);
3635         if (sp) {
3636                 int i;
3637
3638                 for (i = sp->len - 1; i >= 0; i--) {
3639                         struct xfrm_state *x = sp->xvec[i];
3640                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
3641                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3642                                 return 0;
3643                         }
3644                 }
3645         }
3646
3647         pol = NULL;
3648         sk = sk_to_full_sk(sk);
3649         if (sk && sk->sk_policy[dir]) {
3650                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3651                 if (IS_ERR(pol)) {
3652                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3653                         return 0;
3654                 }
3655         }
3656
3657         if (!pol)
3658                 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3659
3660         if (IS_ERR(pol)) {
3661                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3662                 return 0;
3663         }
3664
3665         if (!pol) {
3666                 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3667                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3668                         return 0;
3669                 }
3670
3671                 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3672                         xfrm_secpath_reject(xerr_idx, skb, &fl);
3673                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3674                         return 0;
3675                 }
3676                 return 1;
3677         }
3678
3679         /* This lockless write can happen from different cpus. */
3680         WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
3681
3682         pols[0] = pol;
3683         npols++;
3684 #ifdef CONFIG_XFRM_SUB_POLICY
3685         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3686                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3687                                                     &fl, family,
3688                                                     XFRM_POLICY_IN, if_id);
3689                 if (pols[1]) {
3690                         if (IS_ERR(pols[1])) {
3691                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3692                                 xfrm_pol_put(pols[0]);
3693                                 return 0;
3694                         }
3695                         /* This write can happen from different cpus. */
3696                         WRITE_ONCE(pols[1]->curlft.use_time,
3697                                    ktime_get_real_seconds());
3698                         npols++;
3699                 }
3700         }
3701 #endif
3702
3703         if (pol->action == XFRM_POLICY_ALLOW) {
3704                 static struct sec_path dummy;
3705                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3706                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3707                 struct xfrm_tmpl **tpp = tp;
3708                 int ti = 0;
3709                 int i, k;
3710
3711                 sp = skb_sec_path(skb);
3712                 if (!sp)
3713                         sp = &dummy;
3714
3715                 for (pi = 0; pi < npols; pi++) {
3716                         if (pols[pi] != pol &&
3717                             pols[pi]->action != XFRM_POLICY_ALLOW) {
3718                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3719                                 goto reject;
3720                         }
3721                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3722                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3723                                 goto reject_error;
3724                         }
3725                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
3726                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3727                 }
3728                 xfrm_nr = ti;
3729
3730                 if (npols > 1) {
3731                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3732                         tpp = stp;
3733                 }
3734
3735                 /* For each tunnel xfrm, find the first matching tmpl.
3736                  * For each tmpl before that, find corresponding xfrm.
3737                  * Order is _important_. Later we will implement
3738                  * some barriers, but at the moment barriers
3739                  * are implied between each two transformations.
3740                  * Upon success, marks secpath entries as having been
3741                  * verified to allow them to be skipped in future policy
3742                  * checks (e.g. nested tunnels).
3743                  */
3744                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3745                         k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
3746                         if (k < 0) {
3747                                 if (k < -1)
3748                                         /* "-2 - errored_index" returned */
3749                                         xerr_idx = -(2+k);
3750                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3751                                 goto reject;
3752                         }
3753                 }
3754
3755                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3756                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3757                         goto reject;
3758                 }
3759
3760                 xfrm_pols_put(pols, npols);
3761                 sp->verified_cnt = k;
3762
3763                 return 1;
3764         }
3765         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3766
3767 reject:
3768         xfrm_secpath_reject(xerr_idx, skb, &fl);
3769 reject_error:
3770         xfrm_pols_put(pols, npols);
3771         return 0;
3772 }
3773 EXPORT_SYMBOL(__xfrm_policy_check);
3774
3775 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3776 {
3777         struct net *net = dev_net(skb->dev);
3778         struct flowi fl;
3779         struct dst_entry *dst;
3780         int res = 1;
3781
3782         if (xfrm_decode_session(skb, &fl, family) < 0) {
3783                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3784                 return 0;
3785         }
3786
3787         skb_dst_force(skb);
3788         if (!skb_dst(skb)) {
3789                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3790                 return 0;
3791         }
3792
3793         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3794         if (IS_ERR(dst)) {
3795                 res = 0;
3796                 dst = NULL;
3797         }
3798         skb_dst_set(skb, dst);
3799         return res;
3800 }
3801 EXPORT_SYMBOL(__xfrm_route_forward);
3802
3803 /* Optimize later using cookies and generation ids. */
3804
3805 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3806 {
3807         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3808          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3809          * get validated by dst_ops->check on every use.  We do this
3810          * because when a normal route referenced by an XFRM dst is
3811          * obsoleted we do not go looking around for all parent
3812          * referencing XFRM dsts so that we can invalidate them.  It
3813          * is just too much work.  Instead we make the checks here on
3814          * every use.  For example:
3815          *
3816          *      XFRM dst A --> IPv4 dst X
3817          *
3818          * X is the "xdst->route" of A (X is also the "dst->path" of A
3819          * in this example).  If X is marked obsolete, "A" will not
3820          * notice.  That's what we are validating here via the
3821          * stale_bundle() check.
3822          *
3823          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3824          * be marked on it.
3825          * This will force stale_bundle() to fail on any xdst bundle with
3826          * this dst linked in it.
3827          */
3828         if (dst->obsolete < 0 && !stale_bundle(dst))
3829                 return dst;
3830
3831         return NULL;
3832 }
3833
3834 static int stale_bundle(struct dst_entry *dst)
3835 {
3836         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3837 }
3838
3839 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3840 {
3841         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3842                 dst->dev = blackhole_netdev;
3843                 dev_hold(dst->dev);
3844                 dev_put(dev);
3845         }
3846 }
3847 EXPORT_SYMBOL(xfrm_dst_ifdown);
3848
3849 static void xfrm_link_failure(struct sk_buff *skb)
3850 {
3851         /* Impossible. Such dst must be popped before reaches point of failure. */
3852 }
3853
3854 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3855 {
3856         if (dst) {
3857                 if (dst->obsolete) {
3858                         dst_release(dst);
3859                         dst = NULL;
3860                 }
3861         }
3862         return dst;
3863 }
3864
3865 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3866 {
3867         while (nr--) {
3868                 struct xfrm_dst *xdst = bundle[nr];
3869                 u32 pmtu, route_mtu_cached;
3870                 struct dst_entry *dst;
3871
3872                 dst = &xdst->u.dst;
3873                 pmtu = dst_mtu(xfrm_dst_child(dst));
3874                 xdst->child_mtu_cached = pmtu;
3875
3876                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3877
3878                 route_mtu_cached = dst_mtu(xdst->route);
3879                 xdst->route_mtu_cached = route_mtu_cached;
3880
3881                 if (pmtu > route_mtu_cached)
3882                         pmtu = route_mtu_cached;
3883
3884                 dst_metric_set(dst, RTAX_MTU, pmtu);
3885         }
3886 }
3887
3888 /* Check that the bundle accepts the flow and its components are
3889  * still valid.
3890  */
3891
3892 static int xfrm_bundle_ok(struct xfrm_dst *first)
3893 {
3894         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3895         struct dst_entry *dst = &first->u.dst;
3896         struct xfrm_dst *xdst;
3897         int start_from, nr;
3898         u32 mtu;
3899
3900         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3901             (dst->dev && !netif_running(dst->dev)))
3902                 return 0;
3903
3904         if (dst->flags & DST_XFRM_QUEUE)
3905                 return 1;
3906
3907         start_from = nr = 0;
3908         do {
3909                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3910
3911                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3912                         return 0;
3913                 if (xdst->xfrm_genid != dst->xfrm->genid)
3914                         return 0;
3915                 if (xdst->num_pols > 0 &&
3916                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3917                         return 0;
3918
3919                 bundle[nr++] = xdst;
3920
3921                 mtu = dst_mtu(xfrm_dst_child(dst));
3922                 if (xdst->child_mtu_cached != mtu) {
3923                         start_from = nr;
3924                         xdst->child_mtu_cached = mtu;
3925                 }
3926
3927                 if (!dst_check(xdst->route, xdst->route_cookie))
3928                         return 0;
3929                 mtu = dst_mtu(xdst->route);
3930                 if (xdst->route_mtu_cached != mtu) {
3931                         start_from = nr;
3932                         xdst->route_mtu_cached = mtu;
3933                 }
3934
3935                 dst = xfrm_dst_child(dst);
3936         } while (dst->xfrm);
3937
3938         if (likely(!start_from))
3939                 return 1;
3940
3941         xdst = bundle[start_from - 1];
3942         mtu = xdst->child_mtu_cached;
3943         while (start_from--) {
3944                 dst = &xdst->u.dst;
3945
3946                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3947                 if (mtu > xdst->route_mtu_cached)
3948                         mtu = xdst->route_mtu_cached;
3949                 dst_metric_set(dst, RTAX_MTU, mtu);
3950                 if (!start_from)
3951                         break;
3952
3953                 xdst = bundle[start_from - 1];
3954                 xdst->child_mtu_cached = mtu;
3955         }
3956
3957         return 1;
3958 }
3959
3960 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3961 {
3962         return dst_metric_advmss(xfrm_dst_path(dst));
3963 }
3964
3965 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3966 {
3967         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3968
3969         return mtu ? : dst_mtu(xfrm_dst_path(dst));
3970 }
3971
3972 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3973                                         const void *daddr)
3974 {
3975         while (dst->xfrm) {
3976                 const struct xfrm_state *xfrm = dst->xfrm;
3977
3978                 dst = xfrm_dst_child(dst);
3979
3980                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3981                         continue;
3982                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3983                         daddr = xfrm->coaddr;
3984                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3985                         daddr = &xfrm->id.daddr;
3986         }
3987         return daddr;
3988 }
3989
3990 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3991                                            struct sk_buff *skb,
3992                                            const void *daddr)
3993 {
3994         const struct dst_entry *path = xfrm_dst_path(dst);
3995
3996         if (!skb)
3997                 daddr = xfrm_get_dst_nexthop(dst, daddr);
3998         return path->ops->neigh_lookup(path, skb, daddr);
3999 }
4000
4001 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
4002 {
4003         const struct dst_entry *path = xfrm_dst_path(dst);
4004
4005         daddr = xfrm_get_dst_nexthop(dst, daddr);
4006         path->ops->confirm_neigh(path, daddr);
4007 }
4008
4009 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
4010 {
4011         int err = 0;
4012
4013         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
4014                 return -EAFNOSUPPORT;
4015
4016         spin_lock(&xfrm_policy_afinfo_lock);
4017         if (unlikely(xfrm_policy_afinfo[family] != NULL))
4018                 err = -EEXIST;
4019         else {
4020                 struct dst_ops *dst_ops = afinfo->dst_ops;
4021                 if (likely(dst_ops->kmem_cachep == NULL))
4022                         dst_ops->kmem_cachep = xfrm_dst_cache;
4023                 if (likely(dst_ops->check == NULL))
4024                         dst_ops->check = xfrm_dst_check;
4025                 if (likely(dst_ops->default_advmss == NULL))
4026                         dst_ops->default_advmss = xfrm_default_advmss;
4027                 if (likely(dst_ops->mtu == NULL))
4028                         dst_ops->mtu = xfrm_mtu;
4029                 if (likely(dst_ops->negative_advice == NULL))
4030                         dst_ops->negative_advice = xfrm_negative_advice;
4031                 if (likely(dst_ops->link_failure == NULL))
4032                         dst_ops->link_failure = xfrm_link_failure;
4033                 if (likely(dst_ops->neigh_lookup == NULL))
4034                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
4035                 if (likely(!dst_ops->confirm_neigh))
4036                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
4037                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
4038         }
4039         spin_unlock(&xfrm_policy_afinfo_lock);
4040
4041         return err;
4042 }
4043 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
4044
4045 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
4046 {
4047         struct dst_ops *dst_ops = afinfo->dst_ops;
4048         int i;
4049
4050         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
4051                 if (xfrm_policy_afinfo[i] != afinfo)
4052                         continue;
4053                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
4054                 break;
4055         }
4056
4057         synchronize_rcu();
4058
4059         dst_ops->kmem_cachep = NULL;
4060         dst_ops->check = NULL;
4061         dst_ops->negative_advice = NULL;
4062         dst_ops->link_failure = NULL;
4063 }
4064 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
4065
4066 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
4067 {
4068         spin_lock(&xfrm_if_cb_lock);
4069         rcu_assign_pointer(xfrm_if_cb, ifcb);
4070         spin_unlock(&xfrm_if_cb_lock);
4071 }
4072 EXPORT_SYMBOL(xfrm_if_register_cb);
4073
4074 void xfrm_if_unregister_cb(void)
4075 {
4076         RCU_INIT_POINTER(xfrm_if_cb, NULL);
4077         synchronize_rcu();
4078 }
4079 EXPORT_SYMBOL(xfrm_if_unregister_cb);
4080
4081 #ifdef CONFIG_XFRM_STATISTICS
4082 static int __net_init xfrm_statistics_init(struct net *net)
4083 {
4084         int rv;
4085         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
4086         if (!net->mib.xfrm_statistics)
4087                 return -ENOMEM;
4088         rv = xfrm_proc_init(net);
4089         if (rv < 0)
4090                 free_percpu(net->mib.xfrm_statistics);
4091         return rv;
4092 }
4093
4094 static void xfrm_statistics_fini(struct net *net)
4095 {
4096         xfrm_proc_fini(net);
4097         free_percpu(net->mib.xfrm_statistics);
4098 }
4099 #else
4100 static int __net_init xfrm_statistics_init(struct net *net)
4101 {
4102         return 0;
4103 }
4104
4105 static void xfrm_statistics_fini(struct net *net)
4106 {
4107 }
4108 #endif
4109
4110 static int __net_init xfrm_policy_init(struct net *net)
4111 {
4112         unsigned int hmask, sz;
4113         int dir, err;
4114
4115         if (net_eq(net, &init_net)) {
4116                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4117                                            sizeof(struct xfrm_dst),
4118                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4119                                            NULL);
4120                 err = rhashtable_init(&xfrm_policy_inexact_table,
4121                                       &xfrm_pol_inexact_params);
4122                 BUG_ON(err);
4123         }
4124
4125         hmask = 8 - 1;
4126         sz = (hmask+1) * sizeof(struct hlist_head);
4127
4128         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4129         if (!net->xfrm.policy_byidx)
4130                 goto out_byidx;
4131         net->xfrm.policy_idx_hmask = hmask;
4132
4133         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4134                 struct xfrm_policy_hash *htab;
4135
4136                 net->xfrm.policy_count[dir] = 0;
4137                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4138                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4139
4140                 htab = &net->xfrm.policy_bydst[dir];
4141                 htab->table = xfrm_hash_alloc(sz);
4142                 if (!htab->table)
4143                         goto out_bydst;
4144                 htab->hmask = hmask;
4145                 htab->dbits4 = 32;
4146                 htab->sbits4 = 32;
4147                 htab->dbits6 = 128;
4148                 htab->sbits6 = 128;
4149         }
4150         net->xfrm.policy_hthresh.lbits4 = 32;
4151         net->xfrm.policy_hthresh.rbits4 = 32;
4152         net->xfrm.policy_hthresh.lbits6 = 128;
4153         net->xfrm.policy_hthresh.rbits6 = 128;
4154
4155         seqlock_init(&net->xfrm.policy_hthresh.lock);
4156
4157         INIT_LIST_HEAD(&net->xfrm.policy_all);
4158         INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4159         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4160         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4161         return 0;
4162
4163 out_bydst:
4164         for (dir--; dir >= 0; dir--) {
4165                 struct xfrm_policy_hash *htab;
4166
4167                 htab = &net->xfrm.policy_bydst[dir];
4168                 xfrm_hash_free(htab->table, sz);
4169         }
4170         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4171 out_byidx:
4172         return -ENOMEM;
4173 }
4174
4175 static void xfrm_policy_fini(struct net *net)
4176 {
4177         struct xfrm_pol_inexact_bin *b, *t;
4178         unsigned int sz;
4179         int dir;
4180
4181         flush_work(&net->xfrm.policy_hash_work);
4182 #ifdef CONFIG_XFRM_SUB_POLICY
4183         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4184 #endif
4185         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4186
4187         WARN_ON(!list_empty(&net->xfrm.policy_all));
4188
4189         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4190                 struct xfrm_policy_hash *htab;
4191
4192                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4193
4194                 htab = &net->xfrm.policy_bydst[dir];
4195                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4196                 WARN_ON(!hlist_empty(htab->table));
4197                 xfrm_hash_free(htab->table, sz);
4198         }
4199
4200         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4201         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4202         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4203
4204         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4205         list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4206                 __xfrm_policy_inexact_prune_bin(b, true);
4207         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4208 }
4209
4210 static int __net_init xfrm_net_init(struct net *net)
4211 {
4212         int rv;
4213
4214         /* Initialize the per-net locks here */
4215         spin_lock_init(&net->xfrm.xfrm_state_lock);
4216         spin_lock_init(&net->xfrm.xfrm_policy_lock);
4217         seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4218         mutex_init(&net->xfrm.xfrm_cfg_mutex);
4219         net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4220         net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4221         net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4222
4223         rv = xfrm_statistics_init(net);
4224         if (rv < 0)
4225                 goto out_statistics;
4226         rv = xfrm_state_init(net);
4227         if (rv < 0)
4228                 goto out_state;
4229         rv = xfrm_policy_init(net);
4230         if (rv < 0)
4231                 goto out_policy;
4232         rv = xfrm_sysctl_init(net);
4233         if (rv < 0)
4234                 goto out_sysctl;
4235
4236         return 0;
4237
4238 out_sysctl:
4239         xfrm_policy_fini(net);
4240 out_policy:
4241         xfrm_state_fini(net);
4242 out_state:
4243         xfrm_statistics_fini(net);
4244 out_statistics:
4245         return rv;
4246 }
4247
4248 static void __net_exit xfrm_net_exit(struct net *net)
4249 {
4250         xfrm_sysctl_fini(net);
4251         xfrm_policy_fini(net);
4252         xfrm_state_fini(net);
4253         xfrm_statistics_fini(net);
4254 }
4255
4256 static struct pernet_operations __net_initdata xfrm_net_ops = {
4257         .init = xfrm_net_init,
4258         .exit = xfrm_net_exit,
4259 };
4260
4261 void __init xfrm_init(void)
4262 {
4263         register_pernet_subsys(&xfrm_net_ops);
4264         xfrm_dev_init();
4265         xfrm_input_init();
4266
4267 #ifdef CONFIG_XFRM_ESPINTCP
4268         espintcp_init();
4269 #endif
4270 }
4271
4272 #ifdef CONFIG_AUDITSYSCALL
4273 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4274                                          struct audit_buffer *audit_buf)
4275 {
4276         struct xfrm_sec_ctx *ctx = xp->security;
4277         struct xfrm_selector *sel = &xp->selector;
4278
4279         if (ctx)
4280                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4281                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4282
4283         switch (sel->family) {
4284         case AF_INET:
4285                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4286                 if (sel->prefixlen_s != 32)
4287                         audit_log_format(audit_buf, " src_prefixlen=%d",
4288                                          sel->prefixlen_s);
4289                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4290                 if (sel->prefixlen_d != 32)
4291                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4292                                          sel->prefixlen_d);
4293                 break;
4294         case AF_INET6:
4295                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4296                 if (sel->prefixlen_s != 128)
4297                         audit_log_format(audit_buf, " src_prefixlen=%d",
4298                                          sel->prefixlen_s);
4299                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4300                 if (sel->prefixlen_d != 128)
4301                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4302                                          sel->prefixlen_d);
4303                 break;
4304         }
4305 }
4306
4307 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4308 {
4309         struct audit_buffer *audit_buf;
4310
4311         audit_buf = xfrm_audit_start("SPD-add");
4312         if (audit_buf == NULL)
4313                 return;
4314         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4315         audit_log_format(audit_buf, " res=%u", result);
4316         xfrm_audit_common_policyinfo(xp, audit_buf);
4317         audit_log_end(audit_buf);
4318 }
4319 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4320
4321 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4322                               bool task_valid)
4323 {
4324         struct audit_buffer *audit_buf;
4325
4326         audit_buf = xfrm_audit_start("SPD-delete");
4327         if (audit_buf == NULL)
4328                 return;
4329         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4330         audit_log_format(audit_buf, " res=%u", result);
4331         xfrm_audit_common_policyinfo(xp, audit_buf);
4332         audit_log_end(audit_buf);
4333 }
4334 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4335 #endif
4336
4337 #ifdef CONFIG_XFRM_MIGRATE
4338 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4339                                         const struct xfrm_selector *sel_tgt)
4340 {
4341         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4342                 if (sel_tgt->family == sel_cmp->family &&
4343                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4344                                     sel_cmp->family) &&
4345                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4346                                     sel_cmp->family) &&
4347                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4348                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4349                         return true;
4350                 }
4351         } else {
4352                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4353                         return true;
4354                 }
4355         }
4356         return false;
4357 }
4358
4359 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4360                                                     u8 dir, u8 type, struct net *net, u32 if_id)
4361 {
4362         struct xfrm_policy *pol, *ret = NULL;
4363         struct hlist_head *chain;
4364         u32 priority = ~0U;
4365
4366         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4367         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4368         hlist_for_each_entry(pol, chain, bydst) {
4369                 if ((if_id == 0 || pol->if_id == if_id) &&
4370                     xfrm_migrate_selector_match(sel, &pol->selector) &&
4371                     pol->type == type) {
4372                         ret = pol;
4373                         priority = ret->priority;
4374                         break;
4375                 }
4376         }
4377         chain = &net->xfrm.policy_inexact[dir];
4378         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4379                 if ((pol->priority >= priority) && ret)
4380                         break;
4381
4382                 if ((if_id == 0 || pol->if_id == if_id) &&
4383                     xfrm_migrate_selector_match(sel, &pol->selector) &&
4384                     pol->type == type) {
4385                         ret = pol;
4386                         break;
4387                 }
4388         }
4389
4390         xfrm_pol_hold(ret);
4391
4392         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4393
4394         return ret;
4395 }
4396
4397 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4398 {
4399         int match = 0;
4400
4401         if (t->mode == m->mode && t->id.proto == m->proto &&
4402             (m->reqid == 0 || t->reqid == m->reqid)) {
4403                 switch (t->mode) {
4404                 case XFRM_MODE_TUNNEL:
4405                 case XFRM_MODE_BEET:
4406                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4407                                             m->old_family) &&
4408                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
4409                                             m->old_family)) {
4410                                 match = 1;
4411                         }
4412                         break;
4413                 case XFRM_MODE_TRANSPORT:
4414                         /* in case of transport mode, template does not store
4415                            any IP addresses, hence we just compare mode and
4416                            protocol */
4417                         match = 1;
4418                         break;
4419                 default:
4420                         break;
4421                 }
4422         }
4423         return match;
4424 }
4425
4426 /* update endpoint address(es) of template(s) */
4427 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4428                                struct xfrm_migrate *m, int num_migrate,
4429                                struct netlink_ext_ack *extack)
4430 {
4431         struct xfrm_migrate *mp;
4432         int i, j, n = 0;
4433
4434         write_lock_bh(&pol->lock);
4435         if (unlikely(pol->walk.dead)) {
4436                 /* target policy has been deleted */
4437                 NL_SET_ERR_MSG(extack, "Target policy not found");
4438                 write_unlock_bh(&pol->lock);
4439                 return -ENOENT;
4440         }
4441
4442         for (i = 0; i < pol->xfrm_nr; i++) {
4443                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4444                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4445                                 continue;
4446                         n++;
4447                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4448                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4449                                 continue;
4450                         /* update endpoints */
4451                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4452                                sizeof(pol->xfrm_vec[i].id.daddr));
4453                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4454                                sizeof(pol->xfrm_vec[i].saddr));
4455                         pol->xfrm_vec[i].encap_family = mp->new_family;
4456                         /* flush bundles */
4457                         atomic_inc(&pol->genid);
4458                 }
4459         }
4460
4461         write_unlock_bh(&pol->lock);
4462
4463         if (!n)
4464                 return -ENODATA;
4465
4466         return 0;
4467 }
4468
4469 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
4470                               struct netlink_ext_ack *extack)
4471 {
4472         int i, j;
4473
4474         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
4475                 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
4476                 return -EINVAL;
4477         }
4478
4479         for (i = 0; i < num_migrate; i++) {
4480                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4481                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
4482                         NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
4483                         return -EINVAL;
4484                 }
4485
4486                 /* check if there is any duplicated entry */
4487                 for (j = i + 1; j < num_migrate; j++) {
4488                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4489                                     sizeof(m[i].old_daddr)) &&
4490                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4491                                     sizeof(m[i].old_saddr)) &&
4492                             m[i].proto == m[j].proto &&
4493                             m[i].mode == m[j].mode &&
4494                             m[i].reqid == m[j].reqid &&
4495                             m[i].old_family == m[j].old_family) {
4496                                 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
4497                                 return -EINVAL;
4498                         }
4499                 }
4500         }
4501
4502         return 0;
4503 }
4504
4505 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4506                  struct xfrm_migrate *m, int num_migrate,
4507                  struct xfrm_kmaddress *k, struct net *net,
4508                  struct xfrm_encap_tmpl *encap, u32 if_id,
4509                  struct netlink_ext_ack *extack)
4510 {
4511         int i, err, nx_cur = 0, nx_new = 0;
4512         struct xfrm_policy *pol = NULL;
4513         struct xfrm_state *x, *xc;
4514         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4515         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4516         struct xfrm_migrate *mp;
4517
4518         /* Stage 0 - sanity checks */
4519         err = xfrm_migrate_check(m, num_migrate, extack);
4520         if (err < 0)
4521                 goto out;
4522
4523         if (dir >= XFRM_POLICY_MAX) {
4524                 NL_SET_ERR_MSG(extack, "Invalid policy direction");
4525                 err = -EINVAL;
4526                 goto out;
4527         }
4528
4529         /* Stage 1 - find policy */
4530         pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
4531         if (!pol) {
4532                 NL_SET_ERR_MSG(extack, "Target policy not found");
4533                 err = -ENOENT;
4534                 goto out;
4535         }
4536
4537         /* Stage 2 - find and update state(s) */
4538         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4539                 if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4540                         x_cur[nx_cur] = x;
4541                         nx_cur++;
4542                         xc = xfrm_state_migrate(x, mp, encap);
4543                         if (xc) {
4544                                 x_new[nx_new] = xc;
4545                                 nx_new++;
4546                         } else {
4547                                 err = -ENODATA;
4548                                 goto restore_state;
4549                         }
4550                 }
4551         }
4552
4553         /* Stage 3 - update policy */
4554         err = xfrm_policy_migrate(pol, m, num_migrate, extack);
4555         if (err < 0)
4556                 goto restore_state;
4557
4558         /* Stage 4 - delete old state(s) */
4559         if (nx_cur) {
4560                 xfrm_states_put(x_cur, nx_cur);
4561                 xfrm_states_delete(x_cur, nx_cur);
4562         }
4563
4564         /* Stage 5 - announce */
4565         km_migrate(sel, dir, type, m, num_migrate, k, encap);
4566
4567         xfrm_pol_put(pol);
4568
4569         return 0;
4570 out:
4571         return err;
4572
4573 restore_state:
4574         if (pol)
4575                 xfrm_pol_put(pol);
4576         if (nx_cur)
4577                 xfrm_states_put(x_cur, nx_cur);
4578         if (nx_new)
4579                 xfrm_states_delete(x_new, nx_new);
4580
4581         return err;
4582 }
4583 EXPORT_SYMBOL(xfrm_migrate);
4584 #endif