net/xfrm/xfrm_policy.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * xfrm_policy.c
   4  *
   5  * Changes:
   6  *      Mitsuru KANDA @USAGI
   7  *      Kazunori MIYAZAWA @USAGI
   8  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   9  *              IPv6 support
  10  *      Kazunori MIYAZAWA @USAGI
  11  *      YOSHIFUJI Hideaki
  12  *              Split up af-specific portion
  13  *      Derek Atkins <derek@ihtfp.com>          Add the post_input processor
  14  *
  15  */
  16
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/kmod.h>
  20 #include <linux/list.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/notifier.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/netfilter.h>
  26 #include <linux/module.h>
  27 #include <linux/cache.h>
  28 #include <linux/cpu.h>
  29 #include <linux/audit.h>
  30 #include <linux/rhashtable.h>
  31 #include <linux/if_tunnel.h>
  32 #include <net/dst.h>
  33 #include <net/flow.h>
  34 #include <net/inet_ecn.h>
  35 #include <net/xfrm.h>
  36 #include <net/ip.h>
  37 #include <net/gre.h>
  38 #if IS_ENABLED(CONFIG_IPV6_MIP6)
  39 #include <net/mip6.h>
  40 #endif
  41 #ifdef CONFIG_XFRM_STATISTICS
  42 #include <net/snmp.h>
  43 #endif
  44 #ifdef CONFIG_XFRM_ESPINTCP
  45 #include <net/espintcp.h>
  46 #endif
  47
  48 #include "xfrm_hash.h"
  49
  50 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  51 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  52 #define XFRM_MAX_QUEUE_LEN      100
  53
  54 struct xfrm_flo {
  55         struct dst_entry *dst_orig;
  56         u8 flags;
  57 };
  58
  59 /* prefixes smaller than this are stored in lists, not trees. */
  60 #define INEXACT_PREFIXLEN_IPV4  16
  61 #define INEXACT_PREFIXLEN_IPV6  48
  62
  63 struct xfrm_pol_inexact_node {
  64         struct rb_node node;
  65         union {
  66                 xfrm_address_t addr;
  67                 struct rcu_head rcu;
  68         };
  69         u8 prefixlen;
  70
  71         struct rb_root root;
  72
  73         /* the policies matching this node, can be empty list */
  74         struct hlist_head hhead;
  75 };
  76
  77 /* xfrm inexact policy search tree:
  78  * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
  79  *  |
  80  * +---- root_d: sorted by daddr:prefix
  81  * |                 |
  82  * |        xfrm_pol_inexact_node
  83  * |                 |
  84  * |                 +- root: sorted by saddr/prefix
  85  * |                 |              |
  86  * |                 |         xfrm_pol_inexact_node
  87  * |                 |              |
  88  * |                 |              + root: unused
  89  * |                 |              |
  90  * |                 |              + hhead: saddr:daddr policies
  91  * |                 |
  92  * |                 +- coarse policies and all any:daddr policies
  93  * |
  94  * +---- root_s: sorted by saddr:prefix
  95  * |                 |
  96  * |        xfrm_pol_inexact_node
  97  * |                 |
  98  * |                 + root: unused
  99  * |                 |
 100  * |                 + hhead: saddr:any policies
 101  * |
 102  * +---- coarse policies and all any:any policies
 103  *
 104  * Lookups return four candidate lists:
 105  * 1. any:any list from top-level xfrm_pol_inexact_bin
 106  * 2. any:daddr list from daddr tree
 107  * 3. saddr:daddr list from 2nd level daddr tree
 108  * 4. saddr:any list from saddr tree
 109  *
 110  * This result set then needs to be searched for the policy with
 111  * the lowest priority.  If two results have same prio, youngest one wins.
 112  */
 113
 114 struct xfrm_pol_inexact_key {
 115         possible_net_t net;
 116         u32 if_id;
 117         u16 family;
 118         u8 dir, type;
 119 };
 120
 121 struct xfrm_pol_inexact_bin {
 122         struct xfrm_pol_inexact_key k;
 123         struct rhash_head head;
 124         /* list containing '*:*' policies */
 125         struct hlist_head hhead;
 126
 127         seqcount_spinlock_t count;
 128         /* tree sorted by daddr/prefix */
 129         struct rb_root root_d;
 130
 131         /* tree sorted by saddr/prefix */
 132         struct rb_root root_s;
 133
 134         /* slow path below */
 135         struct list_head inexact_bins;
 136         struct rcu_head rcu;
 137 };
 138
 139 enum xfrm_pol_inexact_candidate_type {
 140         XFRM_POL_CAND_BOTH,
 141         XFRM_POL_CAND_SADDR,
 142         XFRM_POL_CAND_DADDR,
 143         XFRM_POL_CAND_ANY,
 144
 145         XFRM_POL_CAND_MAX,
 146 };
 147
 148 struct xfrm_pol_inexact_candidates {
 149         struct hlist_head *res[XFRM_POL_CAND_MAX];
 150 };
 151
 152 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
 153 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
 154
 155 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
 156 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 157                                                 __read_mostly;
 158
 159 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
 160
 161 static struct rhashtable xfrm_policy_inexact_table;
 162 static const struct rhashtable_params xfrm_pol_inexact_params;
 163
 164 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
 165 static int stale_bundle(struct dst_entry *dst);
 166 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
 167 static void xfrm_policy_queue_process(struct timer_list *t);
 168
 169 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 170 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 171                                                 int dir);
 172
 173 static struct xfrm_pol_inexact_bin *
 174 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
 175                            u32 if_id);
 176
 177 static struct xfrm_pol_inexact_bin *
 178 xfrm_policy_inexact_lookup_rcu(struct net *net,
 179                                u8 type, u16 family, u8 dir, u32 if_id);
 180 static struct xfrm_policy *
 181 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
 182                         bool excl);
 183 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
 184                                             struct xfrm_policy *policy);
 185
 186 static bool
 187 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
 188                                     struct xfrm_pol_inexact_bin *b,
 189                                     const xfrm_address_t *saddr,
 190                                     const xfrm_address_t *daddr);
 191
 192 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
 193 {
 194         return refcount_inc_not_zero(&policy->refcnt);
 195 }
 196
 197 static inline bool
 198 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 199 {
 200         const struct flowi4 *fl4 = &fl->u.ip4;
 201
 202         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
 203                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
 204                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
 205                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
 206                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
 207                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 208 }
 209
 210 static inline bool
 211 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 212 {
 213         const struct flowi6 *fl6 = &fl->u.ip6;
 214
 215         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
 216                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
 217                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
 218                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
 219                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
 220                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 221 }
 222
 223 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
 224                          unsigned short family)
 225 {
 226         switch (family) {
 227         case AF_INET:
 228                 return __xfrm4_selector_match(sel, fl);
 229         case AF_INET6:
 230                 return __xfrm6_selector_match(sel, fl);
 231         }
 232         return false;
 233 }
 234
 235 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 236 {
 237         const struct xfrm_policy_afinfo *afinfo;
 238
 239         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 240                 return NULL;
 241         rcu_read_lock();
 242         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 243         if (unlikely(!afinfo))
 244                 rcu_read_unlock();
 245         return afinfo;
 246 }
 247
 248 /* Called with rcu_read_lock(). */
 249 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 250 {
 251         return rcu_dereference(xfrm_if_cb);
 252 }
 253
 254 struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 255                                     const xfrm_address_t *saddr,
 256                                     const xfrm_address_t *daddr,
 257                                     int family, u32 mark)
 258 {
 259         const struct xfrm_policy_afinfo *afinfo;
 260         struct dst_entry *dst;
 261
 262         afinfo = xfrm_policy_get_afinfo(family);
 263         if (unlikely(afinfo == NULL))
 264                 return ERR_PTR(-EAFNOSUPPORT);
 265
 266         dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 267
 268         rcu_read_unlock();
 269
 270         return dst;
 271 }
 272 EXPORT_SYMBOL(__xfrm_dst_lookup);
 273
 274 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 275                                                 int tos, int oif,
 276                                                 xfrm_address_t *prev_saddr,
 277                                                 xfrm_address_t *prev_daddr,
 278                                                 int family, u32 mark)
 279 {
 280         struct net *net = xs_net(x);
 281         xfrm_address_t *saddr = &x->props.saddr;
 282         xfrm_address_t *daddr = &x->id.daddr;
 283         struct dst_entry *dst;
 284
 285         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 286                 saddr = x->coaddr;
 287                 daddr = prev_daddr;
 288         }
 289         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 290                 saddr = prev_saddr;
 291                 daddr = x->coaddr;
 292         }
 293
 294         dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 295
 296         if (!IS_ERR(dst)) {
 297                 if (prev_saddr != saddr)
 298                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 299                 if (prev_daddr != daddr)
 300                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 301         }
 302
 303         return dst;
 304 }
 305
 306 static inline unsigned long make_jiffies(long secs)
 307 {
 308         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 309                 return MAX_SCHEDULE_TIMEOUT-1;
 310         else
 311                 return secs*HZ;
 312 }
 313
 314 static void xfrm_policy_timer(struct timer_list *t)
 315 {
 316         struct xfrm_policy *xp = from_timer(xp, t, timer);
 317         time64_t now = ktime_get_real_seconds();
 318         time64_t next = TIME64_MAX;
 319         int warn = 0;
 320         int dir;
 321
 322         read_lock(&xp->lock);
 323
 324         if (unlikely(xp->walk.dead))
 325                 goto out;
 326
 327         dir = xfrm_policy_id2dir(xp->index);
 328
 329         if (xp->lft.hard_add_expires_seconds) {
 330                 time64_t tmo = xp->lft.hard_add_expires_seconds +
 331                         xp->curlft.add_time - now;
 332                 if (tmo <= 0)
 333                         goto expired;
 334                 if (tmo < next)
 335                         next = tmo;
 336         }
 337         if (xp->lft.hard_use_expires_seconds) {
 338                 time64_t tmo = xp->lft.hard_use_expires_seconds +
 339                         (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 340                 if (tmo <= 0)
 341                         goto expired;
 342                 if (tmo < next)
 343                         next = tmo;
 344         }
 345         if (xp->lft.soft_add_expires_seconds) {
 346                 time64_t tmo = xp->lft.soft_add_expires_seconds +
 347                         xp->curlft.add_time - now;
 348                 if (tmo <= 0) {
 349                         warn = 1;
 350                         tmo = XFRM_KM_TIMEOUT;
 351                 }
 352                 if (tmo < next)
 353                         next = tmo;
 354         }
 355         if (xp->lft.soft_use_expires_seconds) {
 356                 time64_t tmo = xp->lft.soft_use_expires_seconds +
 357                         (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 358                 if (tmo <= 0) {
 359                         warn = 1;
 360                         tmo = XFRM_KM_TIMEOUT;
 361                 }
 362                 if (tmo < next)
 363                         next = tmo;
 364         }
 365
 366         if (warn)
 367                 km_policy_expired(xp, dir, 0, 0);
 368         if (next != TIME64_MAX &&
 369             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 370                 xfrm_pol_hold(xp);
 371
 372 out:
 373         read_unlock(&xp->lock);
 374         xfrm_pol_put(xp);
 375         return;
 376
 377 expired:
 378         read_unlock(&xp->lock);
 379         if (!xfrm_policy_delete(xp, dir))
 380                 km_policy_expired(xp, dir, 1, 0);
 381         xfrm_pol_put(xp);
 382 }
 383
 384 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 385  * SPD calls.
 386  */
 387
 388 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 389 {
 390         struct xfrm_policy *policy;
 391
 392         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 393
 394         if (policy) {
 395                 write_pnet(&policy->xp_net, net);
 396                 INIT_LIST_HEAD(&policy->walk.all);
 397                 INIT_HLIST_NODE(&policy->bydst_inexact_list);
 398                 INIT_HLIST_NODE(&policy->bydst);
 399                 INIT_HLIST_NODE(&policy->byidx);
 400                 rwlock_init(&policy->lock);
 401                 refcount_set(&policy->refcnt, 1);
 402                 skb_queue_head_init(&policy->polq.hold_queue);
 403                 timer_setup(&policy->timer, xfrm_policy_timer, 0);
 404                 timer_setup(&policy->polq.hold_timer,
 405                             xfrm_policy_queue_process, 0);
 406         }
 407         return policy;
 408 }
 409 EXPORT_SYMBOL(xfrm_policy_alloc);
 410
 411 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 412 {
 413         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 414
 415         security_xfrm_policy_free(policy->security);
 416         kfree(policy);
 417 }
 418
 419 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 420
 421 void xfrm_policy_destroy(struct xfrm_policy *policy)
 422 {
 423         BUG_ON(!policy->walk.dead);
 424
 425         if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 426                 BUG();
 427
 428         xfrm_dev_policy_free(policy);
 429         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 430 }
 431 EXPORT_SYMBOL(xfrm_policy_destroy);
 432
 433 /* Rule must be locked. Release descendant resources, announce
 434  * entry dead. The rule must be unlinked from lists to the moment.
 435  */
 436
 437 static void xfrm_policy_kill(struct xfrm_policy *policy)
 438 {
 439         write_lock_bh(&policy->lock);
 440         policy->walk.dead = 1;
 441         write_unlock_bh(&policy->lock);
 442
 443         atomic_inc(&policy->genid);
 444
 445         if (del_timer(&policy->polq.hold_timer))
 446                 xfrm_pol_put(policy);
 447         skb_queue_purge(&policy->polq.hold_queue);
 448
 449         if (del_timer(&policy->timer))
 450                 xfrm_pol_put(policy);
 451
 452         xfrm_pol_put(policy);
 453 }
 454
 455 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 456
 457 static inline unsigned int idx_hash(struct net *net, u32 index)
 458 {
 459         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 460 }
 461
 462 /* calculate policy hash thresholds */
 463 static void __get_hash_thresh(struct net *net,
 464                               unsigned short family, int dir,
 465                               u8 *dbits, u8 *sbits)
 466 {
 467         switch (family) {
 468         case AF_INET:
 469                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 470                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 471                 break;
 472
 473         case AF_INET6:
 474                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 475                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 476                 break;
 477
 478         default:
 479                 *dbits = 0;
 480                 *sbits = 0;
 481         }
 482 }
 483
 484 static struct hlist_head *policy_hash_bysel(struct net *net,
 485                                             const struct xfrm_selector *sel,
 486                                             unsigned short family, int dir)
 487 {
 488         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 489         unsigned int hash;
 490         u8 dbits;
 491         u8 sbits;
 492
 493         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 494         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 495
 496         if (hash == hmask + 1)
 497                 return NULL;
 498
 499         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 500                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 501 }
 502
 503 static struct hlist_head *policy_hash_direct(struct net *net,
 504                                              const xfrm_address_t *daddr,
 505                                              const xfrm_address_t *saddr,
 506                                              unsigned short family, int dir)
 507 {
 508         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 509         unsigned int hash;
 510         u8 dbits;
 511         u8 sbits;
 512
 513         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 514         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 515
 516         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 517                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 518 }
 519
 520 static void xfrm_dst_hash_transfer(struct net *net,
 521                                    struct hlist_head *list,
 522                                    struct hlist_head *ndsttable,
 523                                    unsigned int nhashmask,
 524                                    int dir)
 525 {
 526         struct hlist_node *tmp, *entry0 = NULL;
 527         struct xfrm_policy *pol;
 528         unsigned int h0 = 0;
 529         u8 dbits;
 530         u8 sbits;
 531
 532 redo:
 533         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 534                 unsigned int h;
 535
 536                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 537                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 538                                 pol->family, nhashmask, dbits, sbits);
 539                 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) {
 540                         hlist_del_rcu(&pol->bydst);
 541                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 542                         h0 = h;
 543                 } else {
 544                         if (h != h0)
 545                                 continue;
 546                         hlist_del_rcu(&pol->bydst);
 547                         hlist_add_behind_rcu(&pol->bydst, entry0);
 548                 }
 549                 entry0 = &pol->bydst;
 550         }
 551         if (!hlist_empty(list)) {
 552                 entry0 = NULL;
 553                 goto redo;
 554         }
 555 }
 556
 557 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 558                                    struct hlist_head *nidxtable,
 559                                    unsigned int nhashmask)
 560 {
 561         struct hlist_node *tmp;
 562         struct xfrm_policy *pol;
 563
 564         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 565                 unsigned int h;
 566
 567                 h = __idx_hash(pol->index, nhashmask);
 568                 hlist_add_head(&pol->byidx, nidxtable+h);
 569         }
 570 }
 571
 572 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 573 {
 574         return ((old_hmask + 1) << 1) - 1;
 575 }
 576
 577 static void xfrm_bydst_resize(struct net *net, int dir)
 578 {
 579         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 580         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 581         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 582         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 583         struct hlist_head *odst;
 584         int i;
 585
 586         if (!ndst)
 587                 return;
 588
 589         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 590         write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
 591
 592         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 593                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 594
 595         for (i = hmask; i >= 0; i--)
 596                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 597
 598         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 599         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 600
 601         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
 602         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 603
 604         synchronize_rcu();
 605
 606         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 607 }
 608
 609 static void xfrm_byidx_resize(struct net *net)
 610 {
 611         unsigned int hmask = net->xfrm.policy_idx_hmask;
 612         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 613         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 614         struct hlist_head *oidx = net->xfrm.policy_byidx;
 615         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 616         int i;
 617
 618         if (!nidx)
 619                 return;
 620
 621         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 622
 623         for (i = hmask; i >= 0; i--)
 624                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 625
 626         net->xfrm.policy_byidx = nidx;
 627         net->xfrm.policy_idx_hmask = nhashmask;
 628
 629         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 630
 631         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 632 }
 633
 634 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 635 {
 636         unsigned int cnt = net->xfrm.policy_count[dir];
 637         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 638
 639         if (total)
 640                 *total += cnt;
 641
 642         if ((hmask + 1) < xfrm_policy_hashmax &&
 643             cnt > hmask)
 644                 return 1;
 645
 646         return 0;
 647 }
 648
 649 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 650 {
 651         unsigned int hmask = net->xfrm.policy_idx_hmask;
 652
 653         if ((hmask + 1) < xfrm_policy_hashmax &&
 654             total > hmask)
 655                 return 1;
 656
 657         return 0;
 658 }
 659
 660 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 661 {
 662         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 663         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 664         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 665         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 666         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 667         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 668         si->spdhcnt = net->xfrm.policy_idx_hmask;
 669         si->spdhmcnt = xfrm_policy_hashmax;
 670 }
 671 EXPORT_SYMBOL(xfrm_spd_getinfo);
 672
 673 static DEFINE_MUTEX(hash_resize_mutex);
 674 static void xfrm_hash_resize(struct work_struct *work)
 675 {
 676         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 677         int dir, total;
 678
 679         mutex_lock(&hash_resize_mutex);
 680
 681         total = 0;
 682         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 683                 if (xfrm_bydst_should_resize(net, dir, &total))
 684                         xfrm_bydst_resize(net, dir);
 685         }
 686         if (xfrm_byidx_should_resize(net, total))
 687                 xfrm_byidx_resize(net);
 688
 689         mutex_unlock(&hash_resize_mutex);
 690 }
 691
 692 /* Make sure *pol can be inserted into fastbin.
 693  * Useful to check that later insert requests will be successful
 694  * (provided xfrm_policy_lock is held throughout).
 695  */
 696 static struct xfrm_pol_inexact_bin *
 697 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
 698 {
 699         struct xfrm_pol_inexact_bin *bin, *prev;
 700         struct xfrm_pol_inexact_key k = {
 701                 .family = pol->family,
 702                 .type = pol->type,
 703                 .dir = dir,
 704                 .if_id = pol->if_id,
 705         };
 706         struct net *net = xp_net(pol);
 707
 708         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
 709
 710         write_pnet(&k.net, net);
 711         bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
 712                                      xfrm_pol_inexact_params);
 713         if (bin)
 714                 return bin;
 715
 716         bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
 717         if (!bin)
 718                 return NULL;
 719
 720         bin->k = k;
 721         INIT_HLIST_HEAD(&bin->hhead);
 722         bin->root_d = RB_ROOT;
 723         bin->root_s = RB_ROOT;
 724         seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
 725
 726         prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
 727                                                 &bin->k, &bin->head,
 728                                                 xfrm_pol_inexact_params);
 729         if (!prev) {
 730                 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
 731                 return bin;
 732         }
 733
 734         kfree(bin);
 735
 736         return IS_ERR(prev) ? NULL : prev;
 737 }
 738
 739 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
 740                                                int family, u8 prefixlen)
 741 {
 742         if (xfrm_addr_any(addr, family))
 743                 return true;
 744
 745         if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
 746                 return true;
 747
 748         if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
 749                 return true;
 750
 751         return false;
 752 }
 753
 754 static bool
 755 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
 756 {
 757         const xfrm_address_t *addr;
 758         bool saddr_any, daddr_any;
 759         u8 prefixlen;
 760
 761         addr = &policy->selector.saddr;
 762         prefixlen = policy->selector.prefixlen_s;
 763
 764         saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 765                                                        policy->family,
 766                                                        prefixlen);
 767         addr = &policy->selector.daddr;
 768         prefixlen = policy->selector.prefixlen_d;
 769         daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 770                                                        policy->family,
 771                                                        prefixlen);
 772         return saddr_any && daddr_any;
 773 }
 774
 775 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
 776                                        const xfrm_address_t *addr, u8 prefixlen)
 777 {
 778         node->addr = *addr;
 779         node->prefixlen = prefixlen;
 780 }
 781
 782 static struct xfrm_pol_inexact_node *
 783 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
 784 {
 785         struct xfrm_pol_inexact_node *node;
 786
 787         node = kzalloc(sizeof(*node), GFP_ATOMIC);
 788         if (node)
 789                 xfrm_pol_inexact_node_init(node, addr, prefixlen);
 790
 791         return node;
 792 }
 793
 794 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
 795                                   const xfrm_address_t *b,
 796                                   u8 prefixlen, u16 family)
 797 {
 798         u32 ma, mb, mask;
 799         unsigned int pdw, pbi;
 800         int delta = 0;
 801
 802         switch (family) {
 803         case AF_INET:
 804                 if (prefixlen == 0)
 805                         return 0;
 806                 mask = ~0U << (32 - prefixlen);
 807                 ma = ntohl(a->a4) & mask;
 808                 mb = ntohl(b->a4) & mask;
 809                 if (ma < mb)
 810                         delta = -1;
 811                 else if (ma > mb)
 812                         delta = 1;
 813                 break;
 814         case AF_INET6:
 815                 pdw = prefixlen >> 5;
 816                 pbi = prefixlen & 0x1f;
 817
 818                 if (pdw) {
 819                         delta = memcmp(a->a6, b->a6, pdw << 2);
 820                         if (delta)
 821                                 return delta;
 822                 }
 823                 if (pbi) {
 824                         mask = ~0U << (32 - pbi);
 825                         ma = ntohl(a->a6[pdw]) & mask;
 826                         mb = ntohl(b->a6[pdw]) & mask;
 827                         if (ma < mb)
 828                                 delta = -1;
 829                         else if (ma > mb)
 830                                 delta = 1;
 831                 }
 832                 break;
 833         default:
 834                 break;
 835         }
 836
 837         return delta;
 838 }
 839
 840 static void xfrm_policy_inexact_list_reinsert(struct net *net,
 841                                               struct xfrm_pol_inexact_node *n,
 842                                               u16 family)
 843 {
 844         unsigned int matched_s, matched_d;
 845         struct xfrm_policy *policy, *p;
 846
 847         matched_s = 0;
 848         matched_d = 0;
 849
 850         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 851                 struct hlist_node *newpos = NULL;
 852                 bool matches_s, matches_d;
 853
 854                 if (!policy->bydst_reinsert)
 855                         continue;
 856
 857                 WARN_ON_ONCE(policy->family != family);
 858
 859                 policy->bydst_reinsert = false;
 860                 hlist_for_each_entry(p, &n->hhead, bydst) {
 861                         if (policy->priority > p->priority)
 862                                 newpos = &p->bydst;
 863                         else if (policy->priority == p->priority &&
 864                                  policy->pos > p->pos)
 865                                 newpos = &p->bydst;
 866                         else
 867                                 break;
 868                 }
 869
 870                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
 871                         hlist_add_behind_rcu(&policy->bydst, newpos);
 872                 else
 873                         hlist_add_head_rcu(&policy->bydst, &n->hhead);
 874
 875                 /* paranoia checks follow.
 876                  * Check that the reinserted policy matches at least
 877                  * saddr or daddr for current node prefix.
 878                  *
 879                  * Matching both is fine, matching saddr in one policy
 880                  * (but not daddr) and then matching only daddr in another
 881                  * is a bug.
 882                  */
 883                 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
 884                                                    &n->addr,
 885                                                    n->prefixlen,
 886                                                    family) == 0;
 887                 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
 888                                                    &n->addr,
 889                                                    n->prefixlen,
 890                                                    family) == 0;
 891                 if (matches_s && matches_d)
 892                         continue;
 893
 894                 WARN_ON_ONCE(!matches_s && !matches_d);
 895                 if (matches_s)
 896                         matched_s++;
 897                 if (matches_d)
 898                         matched_d++;
 899                 WARN_ON_ONCE(matched_s && matched_d);
 900         }
 901 }
 902
 903 static void xfrm_policy_inexact_node_reinsert(struct net *net,
 904                                               struct xfrm_pol_inexact_node *n,
 905                                               struct rb_root *new,
 906                                               u16 family)
 907 {
 908         struct xfrm_pol_inexact_node *node;
 909         struct rb_node **p, *parent;
 910
 911         /* we should not have another subtree here */
 912         WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
 913 restart:
 914         parent = NULL;
 915         p = &new->rb_node;
 916         while (*p) {
 917                 u8 prefixlen;
 918                 int delta;
 919
 920                 parent = *p;
 921                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 922
 923                 prefixlen = min(node->prefixlen, n->prefixlen);
 924
 925                 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
 926                                                prefixlen, family);
 927                 if (delta < 0) {
 928                         p = &parent->rb_left;
 929                 } else if (delta > 0) {
 930                         p = &parent->rb_right;
 931                 } else {
 932                         bool same_prefixlen = node->prefixlen == n->prefixlen;
 933                         struct xfrm_policy *tmp;
 934
 935                         hlist_for_each_entry(tmp, &n->hhead, bydst) {
 936                                 tmp->bydst_reinsert = true;
 937                                 hlist_del_rcu(&tmp->bydst);
 938                         }
 939
 940                         node->prefixlen = prefixlen;
 941
 942                         xfrm_policy_inexact_list_reinsert(net, node, family);
 943
 944                         if (same_prefixlen) {
 945                                 kfree_rcu(n, rcu);
 946                                 return;
 947                         }
 948
 949                         rb_erase(*p, new);
 950                         kfree_rcu(n, rcu);
 951                         n = node;
 952                         goto restart;
 953                 }
 954         }
 955
 956         rb_link_node_rcu(&n->node, parent, p);
 957         rb_insert_color(&n->node, new);
 958 }
 959
 960 /* merge nodes v and n */
 961 static void xfrm_policy_inexact_node_merge(struct net *net,
 962                                            struct xfrm_pol_inexact_node *v,
 963                                            struct xfrm_pol_inexact_node *n,
 964                                            u16 family)
 965 {
 966         struct xfrm_pol_inexact_node *node;
 967         struct xfrm_policy *tmp;
 968         struct rb_node *rnode;
 969
 970         /* To-be-merged node v has a subtree.
 971          *
 972          * Dismantle it and insert its nodes to n->root.
 973          */
 974         while ((rnode = rb_first(&v->root)) != NULL) {
 975                 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
 976                 rb_erase(&node->node, &v->root);
 977                 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
 978                                                   family);
 979         }
 980
 981         hlist_for_each_entry(tmp, &v->hhead, bydst) {
 982                 tmp->bydst_reinsert = true;
 983                 hlist_del_rcu(&tmp->bydst);
 984         }
 985
 986         xfrm_policy_inexact_list_reinsert(net, n, family);
 987 }
 988
 989 static struct xfrm_pol_inexact_node *
 990 xfrm_policy_inexact_insert_node(struct net *net,
 991                                 struct rb_root *root,
 992                                 xfrm_address_t *addr,
 993                                 u16 family, u8 prefixlen, u8 dir)
 994 {
 995         struct xfrm_pol_inexact_node *cached = NULL;
 996         struct rb_node **p, *parent = NULL;
 997         struct xfrm_pol_inexact_node *node;
 998
 999         p = &root->rb_node;
1000         while (*p) {
1001                 int delta;
1002
1003                 parent = *p;
1004                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
1005
1006                 delta = xfrm_policy_addr_delta(addr, &node->addr,
1007                                                node->prefixlen,
1008                                                family);
1009                 if (delta == 0 && prefixlen >= node->prefixlen) {
1010                         WARN_ON_ONCE(cached); /* ipsec policies got lost */
1011                         return node;
1012                 }
1013
1014                 if (delta < 0)
1015                         p = &parent->rb_left;
1016                 else
1017                         p = &parent->rb_right;
1018
1019                 if (prefixlen < node->prefixlen) {
1020                         delta = xfrm_policy_addr_delta(addr, &node->addr,
1021                                                        prefixlen,
1022                                                        family);
1023                         if (delta)
1024                                 continue;
1025
1026                         /* This node is a subnet of the new prefix. It needs
1027                          * to be removed and re-inserted with the smaller
1028                          * prefix and all nodes that are now also covered
1029                          * by the reduced prefixlen.
1030                          */
1031                         rb_erase(&node->node, root);
1032
1033                         if (!cached) {
1034                                 xfrm_pol_inexact_node_init(node, addr,
1035                                                            prefixlen);
1036                                 cached = node;
1037                         } else {
1038                                 /* This node also falls within the new
1039                                  * prefixlen. Merge the to-be-reinserted
1040                                  * node and this one.
1041                                  */
1042                                 xfrm_policy_inexact_node_merge(net, node,
1043                                                                cached, family);
1044                                 kfree_rcu(node, rcu);
1045                         }
1046
1047                         /* restart */
1048                         p = &root->rb_node;
1049                         parent = NULL;
1050                 }
1051         }
1052
1053         node = cached;
1054         if (!node) {
1055                 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1056                 if (!node)
1057                         return NULL;
1058         }
1059
1060         rb_link_node_rcu(&node->node, parent, p);
1061         rb_insert_color(&node->node, root);
1062
1063         return node;
1064 }
1065
1066 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1067 {
1068         struct xfrm_pol_inexact_node *node;
1069         struct rb_node *rn = rb_first(r);
1070
1071         while (rn) {
1072                 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1073
1074                 xfrm_policy_inexact_gc_tree(&node->root, rm);
1075                 rn = rb_next(rn);
1076
1077                 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1078                         WARN_ON_ONCE(rm);
1079                         continue;
1080                 }
1081
1082                 rb_erase(&node->node, r);
1083                 kfree_rcu(node, rcu);
1084         }
1085 }
1086
1087 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1088 {
1089         write_seqcount_begin(&b->count);
1090         xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1091         xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1092         write_seqcount_end(&b->count);
1093
1094         if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1095             !hlist_empty(&b->hhead)) {
1096                 WARN_ON_ONCE(net_exit);
1097                 return;
1098         }
1099
1100         if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1101                                    xfrm_pol_inexact_params) == 0) {
1102                 list_del(&b->inexact_bins);
1103                 kfree_rcu(b, rcu);
1104         }
1105 }
1106
1107 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1108 {
1109         struct net *net = read_pnet(&b->k.net);
1110
1111         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1112         __xfrm_policy_inexact_prune_bin(b, false);
1113         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1114 }
1115
1116 static void __xfrm_policy_inexact_flush(struct net *net)
1117 {
1118         struct xfrm_pol_inexact_bin *bin, *t;
1119
1120         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1121
1122         list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1123                 __xfrm_policy_inexact_prune_bin(bin, false);
1124 }
1125
1126 static struct hlist_head *
1127 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1128                                 struct xfrm_policy *policy, u8 dir)
1129 {
1130         struct xfrm_pol_inexact_node *n;
1131         struct net *net;
1132
1133         net = xp_net(policy);
1134         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1135
1136         if (xfrm_policy_inexact_insert_use_any_list(policy))
1137                 return &bin->hhead;
1138
1139         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1140                                                policy->family,
1141                                                policy->selector.prefixlen_d)) {
1142                 write_seqcount_begin(&bin->count);
1143                 n = xfrm_policy_inexact_insert_node(net,
1144                                                     &bin->root_s,
1145                                                     &policy->selector.saddr,
1146                                                     policy->family,
1147                                                     policy->selector.prefixlen_s,
1148                                                     dir);
1149                 write_seqcount_end(&bin->count);
1150                 if (!n)
1151                         return NULL;
1152
1153                 return &n->hhead;
1154         }
1155
1156         /* daddr is fixed */
1157         write_seqcount_begin(&bin->count);
1158         n = xfrm_policy_inexact_insert_node(net,
1159                                             &bin->root_d,
1160                                             &policy->selector.daddr,
1161                                             policy->family,
1162                                             policy->selector.prefixlen_d, dir);
1163         write_seqcount_end(&bin->count);
1164         if (!n)
1165                 return NULL;
1166
1167         /* saddr is wildcard */
1168         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1169                                                policy->family,
1170                                                policy->selector.prefixlen_s))
1171                 return &n->hhead;
1172
1173         write_seqcount_begin(&bin->count);
1174         n = xfrm_policy_inexact_insert_node(net,
1175                                             &n->root,
1176                                             &policy->selector.saddr,
1177                                             policy->family,
1178                                             policy->selector.prefixlen_s, dir);
1179         write_seqcount_end(&bin->count);
1180         if (!n)
1181                 return NULL;
1182
1183         return &n->hhead;
1184 }
1185
1186 static struct xfrm_policy *
1187 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1188 {
1189         struct xfrm_pol_inexact_bin *bin;
1190         struct xfrm_policy *delpol;
1191         struct hlist_head *chain;
1192         struct net *net;
1193
1194         bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1195         if (!bin)
1196                 return ERR_PTR(-ENOMEM);
1197
1198         net = xp_net(policy);
1199         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1200
1201         chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1202         if (!chain) {
1203                 __xfrm_policy_inexact_prune_bin(bin, false);
1204                 return ERR_PTR(-ENOMEM);
1205         }
1206
1207         delpol = xfrm_policy_insert_list(chain, policy, excl);
1208         if (delpol && excl) {
1209                 __xfrm_policy_inexact_prune_bin(bin, false);
1210                 return ERR_PTR(-EEXIST);
1211         }
1212
1213         chain = &net->xfrm.policy_inexact[dir];
1214         xfrm_policy_insert_inexact_list(chain, policy);
1215
1216         if (delpol)
1217                 __xfrm_policy_inexact_prune_bin(bin, false);
1218
1219         return delpol;
1220 }
1221
1222 static void xfrm_hash_rebuild(struct work_struct *work)
1223 {
1224         struct net *net = container_of(work, struct net,
1225                                        xfrm.policy_hthresh.work);
1226         unsigned int hmask;
1227         struct xfrm_policy *pol;
1228         struct xfrm_policy *policy;
1229         struct hlist_head *chain;
1230         struct hlist_head *odst;
1231         struct hlist_node *newpos;
1232         int i;
1233         int dir;
1234         unsigned seq;
1235         u8 lbits4, rbits4, lbits6, rbits6;
1236
1237         mutex_lock(&hash_resize_mutex);
1238
1239         /* read selector prefixlen thresholds */
1240         do {
1241                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1242
1243                 lbits4 = net->xfrm.policy_hthresh.lbits4;
1244                 rbits4 = net->xfrm.policy_hthresh.rbits4;
1245                 lbits6 = net->xfrm.policy_hthresh.lbits6;
1246                 rbits6 = net->xfrm.policy_hthresh.rbits6;
1247         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1248
1249         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1250         write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
1251
1252         /* make sure that we can insert the indirect policies again before
1253          * we start with destructive action.
1254          */
1255         list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1256                 struct xfrm_pol_inexact_bin *bin;
1257                 u8 dbits, sbits;
1258
1259                 dir = xfrm_policy_id2dir(policy->index);
1260                 if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1261                         continue;
1262
1263                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1264                         if (policy->family == AF_INET) {
1265                                 dbits = rbits4;
1266                                 sbits = lbits4;
1267                         } else {
1268                                 dbits = rbits6;
1269                                 sbits = lbits6;
1270                         }
1271                 } else {
1272                         if (policy->family == AF_INET) {
1273                                 dbits = lbits4;
1274                                 sbits = rbits4;
1275                         } else {
1276                                 dbits = lbits6;
1277                                 sbits = rbits6;
1278                         }
1279                 }
1280
1281                 if (policy->selector.prefixlen_d < dbits ||
1282                     policy->selector.prefixlen_s < sbits)
1283                         continue;
1284
1285                 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1286                 if (!bin)
1287                         goto out_unlock;
1288
1289                 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1290                         goto out_unlock;
1291         }
1292
1293         /* reset the bydst and inexact table in all directions */
1294         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1295                 struct hlist_node *n;
1296
1297                 hlist_for_each_entry_safe(policy, n,
1298                                           &net->xfrm.policy_inexact[dir],
1299                                           bydst_inexact_list) {
1300                         hlist_del_rcu(&policy->bydst);
1301                         hlist_del_init(&policy->bydst_inexact_list);
1302                 }
1303
1304                 hmask = net->xfrm.policy_bydst[dir].hmask;
1305                 odst = net->xfrm.policy_bydst[dir].table;
1306                 for (i = hmask; i >= 0; i--) {
1307                         hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1308                                 hlist_del_rcu(&policy->bydst);
1309                 }
1310                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1311                         /* dir out => dst = remote, src = local */
1312                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1313                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1314                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1315                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1316                 } else {
1317                         /* dir in/fwd => dst = local, src = remote */
1318                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1319                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1320                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1321                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1322                 }
1323         }
1324
1325         /* re-insert all policies by order of creation */
1326         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1327                 if (policy->walk.dead)
1328                         continue;
1329                 dir = xfrm_policy_id2dir(policy->index);
1330                 if (dir >= XFRM_POLICY_MAX) {
1331                         /* skip socket policies */
1332                         continue;
1333                 }
1334                 newpos = NULL;
1335                 chain = policy_hash_bysel(net, &policy->selector,
1336                                           policy->family, dir);
1337
1338                 if (!chain) {
1339                         void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1340
1341                         WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1342                         continue;
1343                 }
1344
1345                 hlist_for_each_entry(pol, chain, bydst) {
1346                         if (policy->priority >= pol->priority)
1347                                 newpos = &pol->bydst;
1348                         else
1349                                 break;
1350                 }
1351                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1352                         hlist_add_behind_rcu(&policy->bydst, newpos);
1353                 else
1354                         hlist_add_head_rcu(&policy->bydst, chain);
1355         }
1356
1357 out_unlock:
1358         __xfrm_policy_inexact_flush(net);
1359         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1360         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1361
1362         mutex_unlock(&hash_resize_mutex);
1363 }
1364
1365 void xfrm_policy_hash_rebuild(struct net *net)
1366 {
1367         schedule_work(&net->xfrm.policy_hthresh.work);
1368 }
1369 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1370
1371 /* Generate new index... KAME seems to generate them ordered by cost
1372  * of an absolute inpredictability of ordering of rules. This will not pass. */
1373 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1374 {
1375         static u32 idx_generator;
1376
1377         for (;;) {
1378                 struct hlist_head *list;
1379                 struct xfrm_policy *p;
1380                 u32 idx;
1381                 int found;
1382
1383                 if (!index) {
1384                         idx = (idx_generator | dir);
1385                         idx_generator += 8;
1386                 } else {
1387                         idx = index;
1388                         index = 0;
1389                 }
1390
1391                 if (idx == 0)
1392                         idx = 8;
1393                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1394                 found = 0;
1395                 hlist_for_each_entry(p, list, byidx) {
1396                         if (p->index == idx) {
1397                                 found = 1;
1398                                 break;
1399                         }
1400                 }
1401                 if (!found)
1402                         return idx;
1403         }
1404 }
1405
1406 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1407 {
1408         u32 *p1 = (u32 *) s1;
1409         u32 *p2 = (u32 *) s2;
1410         int len = sizeof(struct xfrm_selector) / sizeof(u32);
1411         int i;
1412
1413         for (i = 0; i < len; i++) {
1414                 if (p1[i] != p2[i])
1415                         return 1;
1416         }
1417
1418         return 0;
1419 }
1420
1421 static void xfrm_policy_requeue(struct xfrm_policy *old,
1422                                 struct xfrm_policy *new)
1423 {
1424         struct xfrm_policy_queue *pq = &old->polq;
1425         struct sk_buff_head list;
1426
1427         if (skb_queue_empty(&pq->hold_queue))
1428                 return;
1429
1430         __skb_queue_head_init(&list);
1431
1432         spin_lock_bh(&pq->hold_queue.lock);
1433         skb_queue_splice_init(&pq->hold_queue, &list);
1434         if (del_timer(&pq->hold_timer))
1435                 xfrm_pol_put(old);
1436         spin_unlock_bh(&pq->hold_queue.lock);
1437
1438         pq = &new->polq;
1439
1440         spin_lock_bh(&pq->hold_queue.lock);
1441         skb_queue_splice(&list, &pq->hold_queue);
1442         pq->timeout = XFRM_QUEUE_TMO_MIN;
1443         if (!mod_timer(&pq->hold_timer, jiffies))
1444                 xfrm_pol_hold(new);
1445         spin_unlock_bh(&pq->hold_queue.lock);
1446 }
1447
1448 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1449                                           struct xfrm_policy *pol)
1450 {
1451         return mark->v == pol->mark.v && mark->m == pol->mark.m;
1452 }
1453
1454 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1455 {
1456         const struct xfrm_pol_inexact_key *k = data;
1457         u32 a = k->type << 24 | k->dir << 16 | k->family;
1458
1459         return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1460                             seed);
1461 }
1462
1463 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1464 {
1465         const struct xfrm_pol_inexact_bin *b = data;
1466
1467         return xfrm_pol_bin_key(&b->k, 0, seed);
1468 }
1469
1470 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1471                             const void *ptr)
1472 {
1473         const struct xfrm_pol_inexact_key *key = arg->key;
1474         const struct xfrm_pol_inexact_bin *b = ptr;
1475         int ret;
1476
1477         if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1478                 return -1;
1479
1480         ret = b->k.dir ^ key->dir;
1481         if (ret)
1482                 return ret;
1483
1484         ret = b->k.type ^ key->type;
1485         if (ret)
1486                 return ret;
1487
1488         ret = b->k.family ^ key->family;
1489         if (ret)
1490                 return ret;
1491
1492         return b->k.if_id ^ key->if_id;
1493 }
1494
1495 static const struct rhashtable_params xfrm_pol_inexact_params = {
1496         .head_offset            = offsetof(struct xfrm_pol_inexact_bin, head),
1497         .hashfn                 = xfrm_pol_bin_key,
1498         .obj_hashfn             = xfrm_pol_bin_obj,
1499         .obj_cmpfn              = xfrm_pol_bin_cmp,
1500         .automatic_shrinking    = true,
1501 };
1502
1503 static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1504                                             struct xfrm_policy *policy)
1505 {
1506         struct xfrm_policy *pol, *delpol = NULL;
1507         struct hlist_node *newpos = NULL;
1508         int i = 0;
1509
1510         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1511                 if (pol->type == policy->type &&
1512                     pol->if_id == policy->if_id &&
1513                     !selector_cmp(&pol->selector, &policy->selector) &&
1514                     xfrm_policy_mark_match(&policy->mark, pol) &&
1515                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1516                     !WARN_ON(delpol)) {
1517                         delpol = pol;
1518                         if (policy->priority > pol->priority)
1519                                 continue;
1520                 } else if (policy->priority >= pol->priority) {
1521                         newpos = &pol->bydst_inexact_list;
1522                         continue;
1523                 }
1524                 if (delpol)
1525                         break;
1526         }
1527
1528         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1529                 hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1530         else
1531                 hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1532
1533         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1534                 pol->pos = i;
1535                 i++;
1536         }
1537 }
1538
1539 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1540                                                    struct xfrm_policy *policy,
1541                                                    bool excl)
1542 {
1543         struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1544
1545         hlist_for_each_entry(pol, chain, bydst) {
1546                 if (pol->type == policy->type &&
1547                     pol->if_id == policy->if_id &&
1548                     !selector_cmp(&pol->selector, &policy->selector) &&
1549                     xfrm_policy_mark_match(&policy->mark, pol) &&
1550                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1551                     !WARN_ON(delpol)) {
1552                         if (excl)
1553                                 return ERR_PTR(-EEXIST);
1554                         delpol = pol;
1555                         if (policy->priority > pol->priority)
1556                                 continue;
1557                 } else if (policy->priority >= pol->priority) {
1558                         newpos = pol;
1559                         continue;
1560                 }
1561                 if (delpol)
1562                         break;
1563         }
1564
1565         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1566                 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1567         else
1568                 /* Packet offload policies enter to the head
1569                  * to speed-up lookups.
1570                  */
1571                 hlist_add_head_rcu(&policy->bydst, chain);
1572
1573         return delpol;
1574 }
1575
1576 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1577 {
1578         struct net *net = xp_net(policy);
1579         struct xfrm_policy *delpol;
1580         struct hlist_head *chain;
1581
1582         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1583         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1584         if (chain)
1585                 delpol = xfrm_policy_insert_list(chain, policy, excl);
1586         else
1587                 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1588
1589         if (IS_ERR(delpol)) {
1590                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1591                 return PTR_ERR(delpol);
1592         }
1593
1594         __xfrm_policy_link(policy, dir);
1595
1596         /* After previous checking, family can either be AF_INET or AF_INET6 */
1597         if (policy->family == AF_INET)
1598                 rt_genid_bump_ipv4(net);
1599         else
1600                 rt_genid_bump_ipv6(net);
1601
1602         if (delpol) {
1603                 xfrm_policy_requeue(delpol, policy);
1604                 __xfrm_policy_unlink(delpol, dir);
1605         }
1606         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1607         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1608         policy->curlft.add_time = ktime_get_real_seconds();
1609         policy->curlft.use_time = 0;
1610         if (!mod_timer(&policy->timer, jiffies + HZ))
1611                 xfrm_pol_hold(policy);
1612         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1613
1614         if (delpol)
1615                 xfrm_policy_kill(delpol);
1616         else if (xfrm_bydst_should_resize(net, dir, NULL))
1617                 schedule_work(&net->xfrm.policy_hash_work);
1618
1619         return 0;
1620 }
1621 EXPORT_SYMBOL(xfrm_policy_insert);
1622
1623 static struct xfrm_policy *
1624 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1625                         u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1626                         struct xfrm_sec_ctx *ctx)
1627 {
1628         struct xfrm_policy *pol;
1629
1630         if (!chain)
1631                 return NULL;
1632
1633         hlist_for_each_entry(pol, chain, bydst) {
1634                 if (pol->type == type &&
1635                     pol->if_id == if_id &&
1636                     xfrm_policy_mark_match(mark, pol) &&
1637                     !selector_cmp(sel, &pol->selector) &&
1638                     xfrm_sec_ctx_match(ctx, pol->security))
1639                         return pol;
1640         }
1641
1642         return NULL;
1643 }
1644
1645 struct xfrm_policy *
1646 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1647                       u8 type, int dir, struct xfrm_selector *sel,
1648                       struct xfrm_sec_ctx *ctx, int delete, int *err)
1649 {
1650         struct xfrm_pol_inexact_bin *bin = NULL;
1651         struct xfrm_policy *pol, *ret = NULL;
1652         struct hlist_head *chain;
1653
1654         *err = 0;
1655         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1656         chain = policy_hash_bysel(net, sel, sel->family, dir);
1657         if (!chain) {
1658                 struct xfrm_pol_inexact_candidates cand;
1659                 int i;
1660
1661                 bin = xfrm_policy_inexact_lookup(net, type,
1662                                                  sel->family, dir, if_id);
1663                 if (!bin) {
1664                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1665                         return NULL;
1666                 }
1667
1668                 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1669                                                          &sel->saddr,
1670                                                          &sel->daddr)) {
1671                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1672                         return NULL;
1673                 }
1674
1675                 pol = NULL;
1676                 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1677                         struct xfrm_policy *tmp;
1678
1679                         tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1680                                                       if_id, type, dir,
1681                                                       sel, ctx);
1682                         if (!tmp)
1683                                 continue;
1684
1685                         if (!pol || tmp->pos < pol->pos)
1686                                 pol = tmp;
1687                 }
1688         } else {
1689                 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1690                                               sel, ctx);
1691         }
1692
1693         if (pol) {
1694                 xfrm_pol_hold(pol);
1695                 if (delete) {
1696                         *err = security_xfrm_policy_delete(pol->security);
1697                         if (*err) {
1698                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1699                                 return pol;
1700                         }
1701                         __xfrm_policy_unlink(pol, dir);
1702                 }
1703                 ret = pol;
1704         }
1705         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1706
1707         if (ret && delete)
1708                 xfrm_policy_kill(ret);
1709         if (bin && delete)
1710                 xfrm_policy_inexact_prune_bin(bin);
1711         return ret;
1712 }
1713 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1714
1715 struct xfrm_policy *
1716 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1717                  u8 type, int dir, u32 id, int delete, int *err)
1718 {
1719         struct xfrm_policy *pol, *ret;
1720         struct hlist_head *chain;
1721
1722         *err = -ENOENT;
1723         if (xfrm_policy_id2dir(id) != dir)
1724                 return NULL;
1725
1726         *err = 0;
1727         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1728         chain = net->xfrm.policy_byidx + idx_hash(net, id);
1729         ret = NULL;
1730         hlist_for_each_entry(pol, chain, byidx) {
1731                 if (pol->type == type && pol->index == id &&
1732                     pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1733                         xfrm_pol_hold(pol);
1734                         if (delete) {
1735                                 *err = security_xfrm_policy_delete(
1736                                                                 pol->security);
1737                                 if (*err) {
1738                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1739                                         return pol;
1740                                 }
1741                                 __xfrm_policy_unlink(pol, dir);
1742                         }
1743                         ret = pol;
1744                         break;
1745                 }
1746         }
1747         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1748
1749         if (ret && delete)
1750                 xfrm_policy_kill(ret);
1751         return ret;
1752 }
1753 EXPORT_SYMBOL(xfrm_policy_byid);
1754
1755 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1756 static inline int
1757 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1758 {
1759         struct xfrm_policy *pol;
1760         int err = 0;
1761
1762         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1763                 if (pol->walk.dead ||
1764                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1765                     pol->type != type)
1766                         continue;
1767
1768                 err = security_xfrm_policy_delete(pol->security);
1769                 if (err) {
1770                         xfrm_audit_policy_delete(pol, 0, task_valid);
1771                         return err;
1772                 }
1773         }
1774         return err;
1775 }
1776
1777 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1778                                                      struct net_device *dev,
1779                                                      bool task_valid)
1780 {
1781         struct xfrm_policy *pol;
1782         int err = 0;
1783
1784         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1785                 if (pol->walk.dead ||
1786                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1787                     pol->xdo.dev != dev)
1788                         continue;
1789
1790                 err = security_xfrm_policy_delete(pol->security);
1791                 if (err) {
1792                         xfrm_audit_policy_delete(pol, 0, task_valid);
1793                         return err;
1794                 }
1795         }
1796         return err;
1797 }
1798 #else
1799 static inline int
1800 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1801 {
1802         return 0;
1803 }
1804
1805 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1806                                                      struct net_device *dev,
1807                                                      bool task_valid)
1808 {
1809         return 0;
1810 }
1811 #endif
1812
1813 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1814 {
1815         int dir, err = 0, cnt = 0;
1816         struct xfrm_policy *pol;
1817
1818         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1819
1820         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1821         if (err)
1822                 goto out;
1823
1824 again:
1825         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1826                 dir = xfrm_policy_id2dir(pol->index);
1827                 if (pol->walk.dead ||
1828                     dir >= XFRM_POLICY_MAX ||
1829                     pol->type != type)
1830                         continue;
1831
1832                 __xfrm_policy_unlink(pol, dir);
1833                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1834                 xfrm_dev_policy_delete(pol);
1835                 cnt++;
1836                 xfrm_audit_policy_delete(pol, 1, task_valid);
1837                 xfrm_policy_kill(pol);
1838                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1839                 goto again;
1840         }
1841         if (cnt)
1842                 __xfrm_policy_inexact_flush(net);
1843         else
1844                 err = -ESRCH;
1845 out:
1846         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1847         return err;
1848 }
1849 EXPORT_SYMBOL(xfrm_policy_flush);
1850
1851 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
1852                           bool task_valid)
1853 {
1854         int dir, err = 0, cnt = 0;
1855         struct xfrm_policy *pol;
1856
1857         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1858
1859         err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
1860         if (err)
1861                 goto out;
1862
1863 again:
1864         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1865                 dir = xfrm_policy_id2dir(pol->index);
1866                 if (pol->walk.dead ||
1867                     dir >= XFRM_POLICY_MAX ||
1868                     pol->xdo.dev != dev)
1869                         continue;
1870
1871                 __xfrm_policy_unlink(pol, dir);
1872                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1873                 xfrm_dev_policy_delete(pol);
1874                 cnt++;
1875                 xfrm_audit_policy_delete(pol, 1, task_valid);
1876                 xfrm_policy_kill(pol);
1877                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1878                 goto again;
1879         }
1880         if (cnt)
1881                 __xfrm_policy_inexact_flush(net);
1882         else
1883                 err = -ESRCH;
1884 out:
1885         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1886         return err;
1887 }
1888 EXPORT_SYMBOL(xfrm_dev_policy_flush);
1889
1890 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1891                      int (*func)(struct xfrm_policy *, int, int, void*),
1892                      void *data)
1893 {
1894         struct xfrm_policy *pol;
1895         struct xfrm_policy_walk_entry *x;
1896         int error = 0;
1897
1898         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1899             walk->type != XFRM_POLICY_TYPE_ANY)
1900                 return -EINVAL;
1901
1902         if (list_empty(&walk->walk.all) && walk->seq != 0)
1903                 return 0;
1904
1905         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1906         if (list_empty(&walk->walk.all))
1907                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1908         else
1909                 x = list_first_entry(&walk->walk.all,
1910                                      struct xfrm_policy_walk_entry, all);
1911
1912         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1913                 if (x->dead)
1914                         continue;
1915                 pol = container_of(x, struct xfrm_policy, walk);
1916                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1917                     walk->type != pol->type)
1918                         continue;
1919                 error = func(pol, xfrm_policy_id2dir(pol->index),
1920                              walk->seq, data);
1921                 if (error) {
1922                         list_move_tail(&walk->walk.all, &x->all);
1923                         goto out;
1924                 }
1925                 walk->seq++;
1926         }
1927         if (walk->seq == 0) {
1928                 error = -ENOENT;
1929                 goto out;
1930         }
1931         list_del_init(&walk->walk.all);
1932 out:
1933         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1934         return error;
1935 }
1936 EXPORT_SYMBOL(xfrm_policy_walk);
1937
1938 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1939 {
1940         INIT_LIST_HEAD(&walk->walk.all);
1941         walk->walk.dead = 1;
1942         walk->type = type;
1943         walk->seq = 0;
1944 }
1945 EXPORT_SYMBOL(xfrm_policy_walk_init);
1946
1947 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1948 {
1949         if (list_empty(&walk->walk.all))
1950                 return;
1951
1952         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1953         list_del(&walk->walk.all);
1954         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1955 }
1956 EXPORT_SYMBOL(xfrm_policy_walk_done);
1957
1958 /*
1959  * Find policy to apply to this flow.
1960  *
1961  * Returns 0 if policy found, else an -errno.
1962  */
1963 static int xfrm_policy_match(const struct xfrm_policy *pol,
1964                              const struct flowi *fl,
1965                              u8 type, u16 family, u32 if_id)
1966 {
1967         const struct xfrm_selector *sel = &pol->selector;
1968         int ret = -ESRCH;
1969         bool match;
1970
1971         if (pol->family != family ||
1972             pol->if_id != if_id ||
1973             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1974             pol->type != type)
1975                 return ret;
1976
1977         match = xfrm_selector_match(sel, fl, family);
1978         if (match)
1979                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
1980         return ret;
1981 }
1982
1983 static struct xfrm_pol_inexact_node *
1984 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1985                                 seqcount_spinlock_t *count,
1986                                 const xfrm_address_t *addr, u16 family)
1987 {
1988         const struct rb_node *parent;
1989         int seq;
1990
1991 again:
1992         seq = read_seqcount_begin(count);
1993
1994         parent = rcu_dereference_raw(r->rb_node);
1995         while (parent) {
1996                 struct xfrm_pol_inexact_node *node;
1997                 int delta;
1998
1999                 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
2000
2001                 delta = xfrm_policy_addr_delta(addr, &node->addr,
2002                                                node->prefixlen, family);
2003                 if (delta < 0) {
2004                         parent = rcu_dereference_raw(parent->rb_left);
2005                         continue;
2006                 } else if (delta > 0) {
2007                         parent = rcu_dereference_raw(parent->rb_right);
2008                         continue;
2009                 }
2010
2011                 return node;
2012         }
2013
2014         if (read_seqcount_retry(count, seq))
2015                 goto again;
2016
2017         return NULL;
2018 }
2019
2020 static bool
2021 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
2022                                     struct xfrm_pol_inexact_bin *b,
2023                                     const xfrm_address_t *saddr,
2024                                     const xfrm_address_t *daddr)
2025 {
2026         struct xfrm_pol_inexact_node *n;
2027         u16 family;
2028
2029         if (!b)
2030                 return false;
2031
2032         family = b->k.family;
2033         memset(cand, 0, sizeof(*cand));
2034         cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
2035
2036         n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
2037                                             family);
2038         if (n) {
2039                 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
2040                 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
2041                                                     family);
2042                 if (n)
2043                         cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
2044         }
2045
2046         n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
2047                                             family);
2048         if (n)
2049                 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
2050
2051         return true;
2052 }
2053
2054 static struct xfrm_pol_inexact_bin *
2055 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
2056                                u8 dir, u32 if_id)
2057 {
2058         struct xfrm_pol_inexact_key k = {
2059                 .family = family,
2060                 .type = type,
2061                 .dir = dir,
2062                 .if_id = if_id,
2063         };
2064
2065         write_pnet(&k.net, net);
2066
2067         return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
2068                                  xfrm_pol_inexact_params);
2069 }
2070
2071 static struct xfrm_pol_inexact_bin *
2072 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2073                            u8 dir, u32 if_id)
2074 {
2075         struct xfrm_pol_inexact_bin *bin;
2076
2077         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2078
2079         rcu_read_lock();
2080         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2081         rcu_read_unlock();
2082
2083         return bin;
2084 }
2085
2086 static struct xfrm_policy *
2087 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2088                               struct xfrm_policy *prefer,
2089                               const struct flowi *fl,
2090                               u8 type, u16 family, u32 if_id)
2091 {
2092         u32 priority = prefer ? prefer->priority : ~0u;
2093         struct xfrm_policy *pol;
2094
2095         if (!chain)
2096                 return NULL;
2097
2098         hlist_for_each_entry_rcu(pol, chain, bydst) {
2099                 int err;
2100
2101                 if (pol->priority > priority)
2102                         break;
2103
2104                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2105                 if (err) {
2106                         if (err != -ESRCH)
2107                                 return ERR_PTR(err);
2108
2109                         continue;
2110                 }
2111
2112                 if (prefer) {
2113                         /* matches.  Is it older than *prefer? */
2114                         if (pol->priority == priority &&
2115                             prefer->pos < pol->pos)
2116                                 return prefer;
2117                 }
2118
2119                 return pol;
2120         }
2121
2122         return NULL;
2123 }
2124
2125 static struct xfrm_policy *
2126 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2127                             struct xfrm_policy *prefer,
2128                             const struct flowi *fl,
2129                             u8 type, u16 family, u32 if_id)
2130 {
2131         struct xfrm_policy *tmp;
2132         int i;
2133
2134         for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2135                 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2136                                                     prefer,
2137                                                     fl, type, family, if_id);
2138                 if (!tmp)
2139                         continue;
2140
2141                 if (IS_ERR(tmp))
2142                         return tmp;
2143                 prefer = tmp;
2144         }
2145
2146         return prefer;
2147 }
2148
2149 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2150                                                      const struct flowi *fl,
2151                                                      u16 family, u8 dir,
2152                                                      u32 if_id)
2153 {
2154         struct xfrm_pol_inexact_candidates cand;
2155         const xfrm_address_t *daddr, *saddr;
2156         struct xfrm_pol_inexact_bin *bin;
2157         struct xfrm_policy *pol, *ret;
2158         struct hlist_head *chain;
2159         unsigned int sequence;
2160         int err;
2161
2162         daddr = xfrm_flowi_daddr(fl, family);
2163         saddr = xfrm_flowi_saddr(fl, family);
2164         if (unlikely(!daddr || !saddr))
2165                 return NULL;
2166
2167         rcu_read_lock();
2168  retry:
2169         do {
2170                 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2171                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2172         } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2173
2174         ret = NULL;
2175         hlist_for_each_entry_rcu(pol, chain, bydst) {
2176                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2177                 if (err) {
2178                         if (err == -ESRCH)
2179                                 continue;
2180                         else {
2181                                 ret = ERR_PTR(err);
2182                                 goto fail;
2183                         }
2184                 } else {
2185                         ret = pol;
2186                         break;
2187                 }
2188         }
2189         if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
2190                 goto skip_inexact;
2191
2192         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2193         if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2194                                                          daddr))
2195                 goto skip_inexact;
2196
2197         pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2198                                           family, if_id);
2199         if (pol) {
2200                 ret = pol;
2201                 if (IS_ERR(pol))
2202                         goto fail;
2203         }
2204
2205 skip_inexact:
2206         if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2207                 goto retry;
2208
2209         if (ret && !xfrm_pol_hold_rcu(ret))
2210                 goto retry;
2211 fail:
2212         rcu_read_unlock();
2213
2214         return ret;
2215 }
2216
2217 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2218                                               const struct flowi *fl,
2219                                               u16 family, u8 dir, u32 if_id)
2220 {
2221 #ifdef CONFIG_XFRM_SUB_POLICY
2222         struct xfrm_policy *pol;
2223
2224         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2225                                         dir, if_id);
2226         if (pol != NULL)
2227                 return pol;
2228 #endif
2229         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2230                                          dir, if_id);
2231 }
2232
2233 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2234                                                  const struct flowi *fl,
2235                                                  u16 family, u32 if_id)
2236 {
2237         struct xfrm_policy *pol;
2238
2239         rcu_read_lock();
2240  again:
2241         pol = rcu_dereference(sk->sk_policy[dir]);
2242         if (pol != NULL) {
2243                 bool match;
2244                 int err = 0;
2245
2246                 if (pol->family != family) {
2247                         pol = NULL;
2248                         goto out;
2249                 }
2250
2251                 match = xfrm_selector_match(&pol->selector, fl, family);
2252                 if (match) {
2253                         if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v ||
2254                             pol->if_id != if_id) {
2255                                 pol = NULL;
2256                                 goto out;
2257                         }
2258                         err = security_xfrm_policy_lookup(pol->security,
2259                                                       fl->flowi_secid);
2260                         if (!err) {
2261                                 if (!xfrm_pol_hold_rcu(pol))
2262                                         goto again;
2263                         } else if (err == -ESRCH) {
2264                                 pol = NULL;
2265                         } else {
2266                                 pol = ERR_PTR(err);
2267                         }
2268                 } else
2269                         pol = NULL;
2270         }
2271 out:
2272         rcu_read_unlock();
2273         return pol;
2274 }
2275
2276 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2277 {
2278         struct net *net = xp_net(pol);
2279
2280         list_add(&pol->walk.all, &net->xfrm.policy_all);
2281         net->xfrm.policy_count[dir]++;
2282         xfrm_pol_hold(pol);
2283 }
2284
2285 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2286                                                 int dir)
2287 {
2288         struct net *net = xp_net(pol);
2289
2290         if (list_empty(&pol->walk.all))
2291                 return NULL;
2292
2293         /* Socket policies are not hashed. */
2294         if (!hlist_unhashed(&pol->bydst)) {
2295                 hlist_del_rcu(&pol->bydst);
2296                 hlist_del_init(&pol->bydst_inexact_list);
2297                 hlist_del(&pol->byidx);
2298         }
2299
2300         list_del_init(&pol->walk.all);
2301         net->xfrm.policy_count[dir]--;
2302
2303         return pol;
2304 }
2305
2306 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2307 {
2308         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2309 }
2310
2311 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2312 {
2313         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2314 }
2315
2316 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2317 {
2318         struct net *net = xp_net(pol);
2319
2320         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2321         pol = __xfrm_policy_unlink(pol, dir);
2322         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2323         if (pol) {
2324                 xfrm_dev_policy_delete(pol);
2325                 xfrm_policy_kill(pol);
2326                 return 0;
2327         }
2328         return -ENOENT;
2329 }
2330 EXPORT_SYMBOL(xfrm_policy_delete);
2331
2332 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2333 {
2334         struct net *net = sock_net(sk);
2335         struct xfrm_policy *old_pol;
2336
2337 #ifdef CONFIG_XFRM_SUB_POLICY
2338         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2339                 return -EINVAL;
2340 #endif
2341
2342         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2343         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2344                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2345         if (pol) {
2346                 pol->curlft.add_time = ktime_get_real_seconds();
2347                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2348                 xfrm_sk_policy_link(pol, dir);
2349         }
2350         rcu_assign_pointer(sk->sk_policy[dir], pol);
2351         if (old_pol) {
2352                 if (pol)
2353                         xfrm_policy_requeue(old_pol, pol);
2354
2355                 /* Unlinking succeeds always. This is the only function
2356                  * allowed to delete or replace socket policy.
2357                  */
2358                 xfrm_sk_policy_unlink(old_pol, dir);
2359         }
2360         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2361
2362         if (old_pol) {
2363                 xfrm_policy_kill(old_pol);
2364         }
2365         return 0;
2366 }
2367
2368 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2369 {
2370         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2371         struct net *net = xp_net(old);
2372
2373         if (newp) {
2374                 newp->selector = old->selector;
2375                 if (security_xfrm_policy_clone(old->security,
2376                                                &newp->security)) {
2377                         kfree(newp);
2378                         return NULL;  /* ENOMEM */
2379                 }
2380                 newp->lft = old->lft;
2381                 newp->curlft = old->curlft;
2382                 newp->mark = old->mark;
2383                 newp->if_id = old->if_id;
2384                 newp->action = old->action;
2385                 newp->flags = old->flags;
2386                 newp->xfrm_nr = old->xfrm_nr;
2387                 newp->index = old->index;
2388                 newp->type = old->type;
2389                 newp->family = old->family;
2390                 memcpy(newp->xfrm_vec, old->xfrm_vec,
2391                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2392                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2393                 xfrm_sk_policy_link(newp, dir);
2394                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2395                 xfrm_pol_put(newp);
2396         }
2397         return newp;
2398 }
2399
2400 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2401 {
2402         const struct xfrm_policy *p;
2403         struct xfrm_policy *np;
2404         int i, ret = 0;
2405
2406         rcu_read_lock();
2407         for (i = 0; i < 2; i++) {
2408                 p = rcu_dereference(osk->sk_policy[i]);
2409                 if (p) {
2410                         np = clone_policy(p, i);
2411                         if (unlikely(!np)) {
2412                                 ret = -ENOMEM;
2413                                 break;
2414                         }
2415                         rcu_assign_pointer(sk->sk_policy[i], np);
2416                 }
2417         }
2418         rcu_read_unlock();
2419         return ret;
2420 }
2421
2422 static int
2423 xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2424                xfrm_address_t *remote, unsigned short family, u32 mark)
2425 {
2426         int err;
2427         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2428
2429         if (unlikely(afinfo == NULL))
2430                 return -EINVAL;
2431         err = afinfo->get_saddr(net, oif, local, remote, mark);
2432         rcu_read_unlock();
2433         return err;
2434 }
2435
2436 /* Resolve list of templates for the flow, given policy. */
2437
2438 static int
2439 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2440                       struct xfrm_state **xfrm, unsigned short family)
2441 {
2442         struct net *net = xp_net(policy);
2443         int nx;
2444         int i, error;
2445         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2446         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2447         xfrm_address_t tmp;
2448
2449         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2450                 struct xfrm_state *x;
2451                 xfrm_address_t *remote = daddr;
2452                 xfrm_address_t *local  = saddr;
2453                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2454
2455                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2456                     tmpl->mode == XFRM_MODE_BEET) {
2457                         remote = &tmpl->id.daddr;
2458                         local = &tmpl->saddr;
2459                         if (xfrm_addr_any(local, tmpl->encap_family)) {
2460                                 error = xfrm_get_saddr(net, fl->flowi_oif,
2461                                                        &tmp, remote,
2462                                                        tmpl->encap_family, 0);
2463                                 if (error)
2464                                         goto fail;
2465                                 local = &tmp;
2466                         }
2467                 }
2468
2469                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2470                                     family, policy->if_id);
2471
2472                 if (x && x->km.state == XFRM_STATE_VALID) {
2473                         xfrm[nx++] = x;
2474                         daddr = remote;
2475                         saddr = local;
2476                         continue;
2477                 }
2478                 if (x) {
2479                         error = (x->km.state == XFRM_STATE_ERROR ?
2480                                  -EINVAL : -EAGAIN);
2481                         xfrm_state_put(x);
2482                 } else if (error == -ESRCH) {
2483                         error = -EAGAIN;
2484                 }
2485
2486                 if (!tmpl->optional)
2487                         goto fail;
2488         }
2489         return nx;
2490
2491 fail:
2492         for (nx--; nx >= 0; nx--)
2493                 xfrm_state_put(xfrm[nx]);
2494         return error;
2495 }
2496
2497 static int
2498 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2499                   struct xfrm_state **xfrm, unsigned short family)
2500 {
2501         struct xfrm_state *tp[XFRM_MAX_DEPTH];
2502         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2503         int cnx = 0;
2504         int error;
2505         int ret;
2506         int i;
2507
2508         for (i = 0; i < npols; i++) {
2509                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2510                         error = -ENOBUFS;
2511                         goto fail;
2512                 }
2513
2514                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2515                 if (ret < 0) {
2516                         error = ret;
2517                         goto fail;
2518                 } else
2519                         cnx += ret;
2520         }
2521
2522         /* found states are sorted for outbound processing */
2523         if (npols > 1)
2524                 xfrm_state_sort(xfrm, tpp, cnx, family);
2525
2526         return cnx;
2527
2528  fail:
2529         for (cnx--; cnx >= 0; cnx--)
2530                 xfrm_state_put(tpp[cnx]);
2531         return error;
2532
2533 }
2534
2535 static int xfrm_get_tos(const struct flowi *fl, int family)
2536 {
2537         if (family == AF_INET)
2538                 return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2539
2540         return 0;
2541 }
2542
2543 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2544 {
2545         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2546         struct dst_ops *dst_ops;
2547         struct xfrm_dst *xdst;
2548
2549         if (!afinfo)
2550                 return ERR_PTR(-EINVAL);
2551
2552         switch (family) {
2553         case AF_INET:
2554                 dst_ops = &net->xfrm.xfrm4_dst_ops;
2555                 break;
2556 #if IS_ENABLED(CONFIG_IPV6)
2557         case AF_INET6:
2558                 dst_ops = &net->xfrm.xfrm6_dst_ops;
2559                 break;
2560 #endif
2561         default:
2562                 BUG();
2563         }
2564         xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2565
2566         if (likely(xdst)) {
2567                 memset_after(xdst, 0, u.dst);
2568         } else
2569                 xdst = ERR_PTR(-ENOBUFS);
2570
2571         rcu_read_unlock();
2572
2573         return xdst;
2574 }
2575
2576 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2577                            int nfheader_len)
2578 {
2579         if (dst->ops->family == AF_INET6) {
2580                 struct rt6_info *rt = (struct rt6_info *)dst;
2581                 path->path_cookie = rt6_get_cookie(rt);
2582                 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2583         }
2584 }
2585
2586 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2587                                 const struct flowi *fl)
2588 {
2589         const struct xfrm_policy_afinfo *afinfo =
2590                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2591         int err;
2592
2593         if (!afinfo)
2594                 return -EINVAL;
2595
2596         err = afinfo->fill_dst(xdst, dev, fl);
2597
2598         rcu_read_unlock();
2599
2600         return err;
2601 }
2602
2603
2604 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2605  * all the metrics... Shortly, bundle a bundle.
2606  */
2607
2608 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2609                                             struct xfrm_state **xfrm,
2610                                             struct xfrm_dst **bundle,
2611                                             int nx,
2612                                             const struct flowi *fl,
2613                                             struct dst_entry *dst)
2614 {
2615         const struct xfrm_state_afinfo *afinfo;
2616         const struct xfrm_mode *inner_mode;
2617         struct net *net = xp_net(policy);
2618         unsigned long now = jiffies;
2619         struct net_device *dev;
2620         struct xfrm_dst *xdst_prev = NULL;
2621         struct xfrm_dst *xdst0 = NULL;
2622         int i = 0;
2623         int err;
2624         int header_len = 0;
2625         int nfheader_len = 0;
2626         int trailer_len = 0;
2627         int tos;
2628         int family = policy->selector.family;
2629         xfrm_address_t saddr, daddr;
2630
2631         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2632
2633         tos = xfrm_get_tos(fl, family);
2634
2635         dst_hold(dst);
2636
2637         for (; i < nx; i++) {
2638                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2639                 struct dst_entry *dst1 = &xdst->u.dst;
2640
2641                 err = PTR_ERR(xdst);
2642                 if (IS_ERR(xdst)) {
2643                         dst_release(dst);
2644                         goto put_states;
2645                 }
2646
2647                 bundle[i] = xdst;
2648                 if (!xdst_prev)
2649                         xdst0 = xdst;
2650                 else
2651                         /* Ref count is taken during xfrm_alloc_dst()
2652                          * No need to do dst_clone() on dst1
2653                          */
2654                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2655
2656                 if (xfrm[i]->sel.family == AF_UNSPEC) {
2657                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
2658                                                         xfrm_af2proto(family));
2659                         if (!inner_mode) {
2660                                 err = -EAFNOSUPPORT;
2661                                 dst_release(dst);
2662                                 goto put_states;
2663                         }
2664                 } else
2665                         inner_mode = &xfrm[i]->inner_mode;
2666
2667                 xdst->route = dst;
2668                 dst_copy_metrics(dst1, dst);
2669
2670                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2671                         __u32 mark = 0;
2672                         int oif;
2673
2674                         if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2675                                 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2676
2677                         family = xfrm[i]->props.family;
2678                         oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2679                         dst = xfrm_dst_lookup(xfrm[i], tos, oif,
2680                                               &saddr, &daddr, family, mark);
2681                         err = PTR_ERR(dst);
2682                         if (IS_ERR(dst))
2683                                 goto put_states;
2684                 } else
2685                         dst_hold(dst);
2686
2687                 dst1->xfrm = xfrm[i];
2688                 xdst->xfrm_genid = xfrm[i]->genid;
2689
2690                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2691                 dst1->lastuse = now;
2692
2693                 dst1->input = dst_discard;
2694
2695                 rcu_read_lock();
2696                 afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2697                 if (likely(afinfo))
2698                         dst1->output = afinfo->output;
2699                 else
2700                         dst1->output = dst_discard_out;
2701                 rcu_read_unlock();
2702
2703                 xdst_prev = xdst;
2704
2705                 header_len += xfrm[i]->props.header_len;
2706                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2707                         nfheader_len += xfrm[i]->props.header_len;
2708                 trailer_len += xfrm[i]->props.trailer_len;
2709         }
2710
2711         xfrm_dst_set_child(xdst_prev, dst);
2712         xdst0->path = dst;
2713
2714         err = -ENODEV;
2715         dev = dst->dev;
2716         if (!dev)
2717                 goto free_dst;
2718
2719         xfrm_init_path(xdst0, dst, nfheader_len);
2720         xfrm_init_pmtu(bundle, nx);
2721
2722         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2723              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2724                 err = xfrm_fill_dst(xdst_prev, dev, fl);
2725                 if (err)
2726                         goto free_dst;
2727
2728                 xdst_prev->u.dst.header_len = header_len;
2729                 xdst_prev->u.dst.trailer_len = trailer_len;
2730                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2731                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2732         }
2733
2734         return &xdst0->u.dst;
2735
2736 put_states:
2737         for (; i < nx; i++)
2738                 xfrm_state_put(xfrm[i]);
2739 free_dst:
2740         if (xdst0)
2741                 dst_release_immediate(&xdst0->u.dst);
2742
2743         return ERR_PTR(err);
2744 }
2745
2746 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2747                                 struct xfrm_policy **pols,
2748                                 int *num_pols, int *num_xfrms)
2749 {
2750         int i;
2751
2752         if (*num_pols == 0 || !pols[0]) {
2753                 *num_pols = 0;
2754                 *num_xfrms = 0;
2755                 return 0;
2756         }
2757         if (IS_ERR(pols[0])) {
2758                 *num_pols = 0;
2759                 return PTR_ERR(pols[0]);
2760         }
2761
2762         *num_xfrms = pols[0]->xfrm_nr;
2763
2764 #ifdef CONFIG_XFRM_SUB_POLICY
2765         if (pols[0]->action == XFRM_POLICY_ALLOW &&
2766             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2767                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2768                                                     XFRM_POLICY_TYPE_MAIN,
2769                                                     fl, family,
2770                                                     XFRM_POLICY_OUT,
2771                                                     pols[0]->if_id);
2772                 if (pols[1]) {
2773                         if (IS_ERR(pols[1])) {
2774                                 xfrm_pols_put(pols, *num_pols);
2775                                 *num_pols = 0;
2776                                 return PTR_ERR(pols[1]);
2777                         }
2778                         (*num_pols)++;
2779                         (*num_xfrms) += pols[1]->xfrm_nr;
2780                 }
2781         }
2782 #endif
2783         for (i = 0; i < *num_pols; i++) {
2784                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2785                         *num_xfrms = -1;
2786                         break;
2787                 }
2788         }
2789
2790         return 0;
2791
2792 }
2793
2794 static struct xfrm_dst *
2795 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2796                                const struct flowi *fl, u16 family,
2797                                struct dst_entry *dst_orig)
2798 {
2799         struct net *net = xp_net(pols[0]);
2800         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2801         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2802         struct xfrm_dst *xdst;
2803         struct dst_entry *dst;
2804         int err;
2805
2806         /* Try to instantiate a bundle */
2807         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2808         if (err <= 0) {
2809                 if (err == 0)
2810                         return NULL;
2811
2812                 if (err != -EAGAIN)
2813                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2814                 return ERR_PTR(err);
2815         }
2816
2817         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2818         if (IS_ERR(dst)) {
2819                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2820                 return ERR_CAST(dst);
2821         }
2822
2823         xdst = (struct xfrm_dst *)dst;
2824         xdst->num_xfrms = err;
2825         xdst->num_pols = num_pols;
2826         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2827         xdst->policy_genid = atomic_read(&pols[0]->genid);
2828
2829         return xdst;
2830 }
2831
2832 static void xfrm_policy_queue_process(struct timer_list *t)
2833 {
2834         struct sk_buff *skb;
2835         struct sock *sk;
2836         struct dst_entry *dst;
2837         struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2838         struct net *net = xp_net(pol);
2839         struct xfrm_policy_queue *pq = &pol->polq;
2840         struct flowi fl;
2841         struct sk_buff_head list;
2842         __u32 skb_mark;
2843
2844         spin_lock(&pq->hold_queue.lock);
2845         skb = skb_peek(&pq->hold_queue);
2846         if (!skb) {
2847                 spin_unlock(&pq->hold_queue.lock);
2848                 goto out;
2849         }
2850         dst = skb_dst(skb);
2851         sk = skb->sk;
2852
2853         /* Fixup the mark to support VTI. */
2854         skb_mark = skb->mark;
2855         skb->mark = pol->mark.v;
2856         xfrm_decode_session(skb, &fl, dst->ops->family);
2857         skb->mark = skb_mark;
2858         spin_unlock(&pq->hold_queue.lock);
2859
2860         dst_hold(xfrm_dst_path(dst));
2861         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2862         if (IS_ERR(dst))
2863                 goto purge_queue;
2864
2865         if (dst->flags & DST_XFRM_QUEUE) {
2866                 dst_release(dst);
2867
2868                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2869                         goto purge_queue;
2870
2871                 pq->timeout = pq->timeout << 1;
2872                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2873                         xfrm_pol_hold(pol);
2874                 goto out;
2875         }
2876
2877         dst_release(dst);
2878
2879         __skb_queue_head_init(&list);
2880
2881         spin_lock(&pq->hold_queue.lock);
2882         pq->timeout = 0;
2883         skb_queue_splice_init(&pq->hold_queue, &list);
2884         spin_unlock(&pq->hold_queue.lock);
2885
2886         while (!skb_queue_empty(&list)) {
2887                 skb = __skb_dequeue(&list);
2888
2889                 /* Fixup the mark to support VTI. */
2890                 skb_mark = skb->mark;
2891                 skb->mark = pol->mark.v;
2892                 xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
2893                 skb->mark = skb_mark;
2894
2895                 dst_hold(xfrm_dst_path(skb_dst(skb)));
2896                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2897                 if (IS_ERR(dst)) {
2898                         kfree_skb(skb);
2899                         continue;
2900                 }
2901
2902                 nf_reset_ct(skb);
2903                 skb_dst_drop(skb);
2904                 skb_dst_set(skb, dst);
2905
2906                 dst_output(net, skb->sk, skb);
2907         }
2908
2909 out:
2910         xfrm_pol_put(pol);
2911         return;
2912
2913 purge_queue:
2914         pq->timeout = 0;
2915         skb_queue_purge(&pq->hold_queue);
2916         xfrm_pol_put(pol);
2917 }
2918
2919 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2920 {
2921         unsigned long sched_next;
2922         struct dst_entry *dst = skb_dst(skb);
2923         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2924         struct xfrm_policy *pol = xdst->pols[0];
2925         struct xfrm_policy_queue *pq = &pol->polq;
2926
2927         if (unlikely(skb_fclone_busy(sk, skb))) {
2928                 kfree_skb(skb);
2929                 return 0;
2930         }
2931
2932         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2933                 kfree_skb(skb);
2934                 return -EAGAIN;
2935         }
2936
2937         skb_dst_force(skb);
2938
2939         spin_lock_bh(&pq->hold_queue.lock);
2940
2941         if (!pq->timeout)
2942                 pq->timeout = XFRM_QUEUE_TMO_MIN;
2943
2944         sched_next = jiffies + pq->timeout;
2945
2946         if (del_timer(&pq->hold_timer)) {
2947                 if (time_before(pq->hold_timer.expires, sched_next))
2948                         sched_next = pq->hold_timer.expires;
2949                 xfrm_pol_put(pol);
2950         }
2951
2952         __skb_queue_tail(&pq->hold_queue, skb);
2953         if (!mod_timer(&pq->hold_timer, sched_next))
2954                 xfrm_pol_hold(pol);
2955
2956         spin_unlock_bh(&pq->hold_queue.lock);
2957
2958         return 0;
2959 }
2960
2961 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2962                                                  struct xfrm_flo *xflo,
2963                                                  const struct flowi *fl,
2964                                                  int num_xfrms,
2965                                                  u16 family)
2966 {
2967         int err;
2968         struct net_device *dev;
2969         struct dst_entry *dst;
2970         struct dst_entry *dst1;
2971         struct xfrm_dst *xdst;
2972
2973         xdst = xfrm_alloc_dst(net, family);
2974         if (IS_ERR(xdst))
2975                 return xdst;
2976
2977         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2978             net->xfrm.sysctl_larval_drop ||
2979             num_xfrms <= 0)
2980                 return xdst;
2981
2982         dst = xflo->dst_orig;
2983         dst1 = &xdst->u.dst;
2984         dst_hold(dst);
2985         xdst->route = dst;
2986
2987         dst_copy_metrics(dst1, dst);
2988
2989         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2990         dst1->flags |= DST_XFRM_QUEUE;
2991         dst1->lastuse = jiffies;
2992
2993         dst1->input = dst_discard;
2994         dst1->output = xdst_queue_output;
2995
2996         dst_hold(dst);
2997         xfrm_dst_set_child(xdst, dst);
2998         xdst->path = dst;
2999
3000         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
3001
3002         err = -ENODEV;
3003         dev = dst->dev;
3004         if (!dev)
3005                 goto free_dst;
3006
3007         err = xfrm_fill_dst(xdst, dev, fl);
3008         if (err)
3009                 goto free_dst;
3010
3011 out:
3012         return xdst;
3013
3014 free_dst:
3015         dst_release(dst1);
3016         xdst = ERR_PTR(err);
3017         goto out;
3018 }
3019
3020 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
3021                                            const struct flowi *fl,
3022                                            u16 family, u8 dir,
3023                                            struct xfrm_flo *xflo, u32 if_id)
3024 {
3025         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3026         int num_pols = 0, num_xfrms = 0, err;
3027         struct xfrm_dst *xdst;
3028
3029         /* Resolve policies to use if we couldn't get them from
3030          * previous cache entry */
3031         num_pols = 1;
3032         pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
3033         err = xfrm_expand_policies(fl, family, pols,
3034                                            &num_pols, &num_xfrms);
3035         if (err < 0)
3036                 goto inc_error;
3037         if (num_pols == 0)
3038                 return NULL;
3039         if (num_xfrms <= 0)
3040                 goto make_dummy_bundle;
3041
3042         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
3043                                               xflo->dst_orig);
3044         if (IS_ERR(xdst)) {
3045                 err = PTR_ERR(xdst);
3046                 if (err == -EREMOTE) {
3047                         xfrm_pols_put(pols, num_pols);
3048                         return NULL;
3049                 }
3050
3051                 if (err != -EAGAIN)
3052                         goto error;
3053                 goto make_dummy_bundle;
3054         } else if (xdst == NULL) {
3055                 num_xfrms = 0;
3056                 goto make_dummy_bundle;
3057         }
3058
3059         return xdst;
3060
3061 make_dummy_bundle:
3062         /* We found policies, but there's no bundles to instantiate:
3063          * either because the policy blocks, has no transformations or
3064          * we could not build template (no xfrm_states).*/
3065         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
3066         if (IS_ERR(xdst)) {
3067                 xfrm_pols_put(pols, num_pols);
3068                 return ERR_CAST(xdst);
3069         }
3070         xdst->num_pols = num_pols;
3071         xdst->num_xfrms = num_xfrms;
3072         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
3073
3074         return xdst;
3075
3076 inc_error:
3077         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3078 error:
3079         xfrm_pols_put(pols, num_pols);
3080         return ERR_PTR(err);
3081 }
3082
3083 static struct dst_entry *make_blackhole(struct net *net, u16 family,
3084                                         struct dst_entry *dst_orig)
3085 {
3086         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3087         struct dst_entry *ret;
3088
3089         if (!afinfo) {
3090                 dst_release(dst_orig);
3091                 return ERR_PTR(-EINVAL);
3092         } else {
3093                 ret = afinfo->blackhole_route(net, dst_orig);
3094         }
3095         rcu_read_unlock();
3096
3097         return ret;
3098 }
3099
3100 /* Finds/creates a bundle for given flow and if_id
3101  *
3102  * At the moment we eat a raw IP route. Mostly to speed up lookups
3103  * on interfaces with disabled IPsec.
3104  *
3105  * xfrm_lookup uses an if_id of 0 by default, and is provided for
3106  * compatibility
3107  */
3108 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3109                                         struct dst_entry *dst_orig,
3110                                         const struct flowi *fl,
3111                                         const struct sock *sk,
3112                                         int flags, u32 if_id)
3113 {
3114         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3115         struct xfrm_dst *xdst;
3116         struct dst_entry *dst, *route;
3117         u16 family = dst_orig->ops->family;
3118         u8 dir = XFRM_POLICY_OUT;
3119         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3120
3121         dst = NULL;
3122         xdst = NULL;
3123         route = NULL;
3124
3125         sk = sk_const_to_full_sk(sk);
3126         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3127                 num_pols = 1;
3128                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3129                                                 if_id);
3130                 err = xfrm_expand_policies(fl, family, pols,
3131                                            &num_pols, &num_xfrms);
3132                 if (err < 0)
3133                         goto dropdst;
3134
3135                 if (num_pols) {
3136                         if (num_xfrms <= 0) {
3137                                 drop_pols = num_pols;
3138                                 goto no_transform;
3139                         }
3140
3141                         xdst = xfrm_resolve_and_create_bundle(
3142                                         pols, num_pols, fl,
3143                                         family, dst_orig);
3144
3145                         if (IS_ERR(xdst)) {
3146                                 xfrm_pols_put(pols, num_pols);
3147                                 err = PTR_ERR(xdst);
3148                                 if (err == -EREMOTE)
3149                                         goto nopol;
3150
3151                                 goto dropdst;
3152                         } else if (xdst == NULL) {
3153                                 num_xfrms = 0;
3154                                 drop_pols = num_pols;
3155                                 goto no_transform;
3156                         }
3157
3158                         route = xdst->route;
3159                 }
3160         }
3161
3162         if (xdst == NULL) {
3163                 struct xfrm_flo xflo;
3164
3165                 xflo.dst_orig = dst_orig;
3166                 xflo.flags = flags;
3167
3168                 /* To accelerate a bit...  */
3169                 if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3170                                !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3171                         goto nopol;
3172
3173                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3174                 if (xdst == NULL)
3175                         goto nopol;
3176                 if (IS_ERR(xdst)) {
3177                         err = PTR_ERR(xdst);
3178                         goto dropdst;
3179                 }
3180
3181                 num_pols = xdst->num_pols;
3182                 num_xfrms = xdst->num_xfrms;
3183                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3184                 route = xdst->route;
3185         }
3186
3187         dst = &xdst->u.dst;
3188         if (route == NULL && num_xfrms > 0) {
3189                 /* The only case when xfrm_bundle_lookup() returns a
3190                  * bundle with null route, is when the template could
3191                  * not be resolved. It means policies are there, but
3192                  * bundle could not be created, since we don't yet
3193                  * have the xfrm_state's. We need to wait for KM to
3194                  * negotiate new SA's or bail out with error.*/
3195                 if (net->xfrm.sysctl_larval_drop) {
3196                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3197                         err = -EREMOTE;
3198                         goto error;
3199                 }
3200
3201                 err = -EAGAIN;
3202
3203                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3204                 goto error;
3205         }
3206
3207 no_transform:
3208         if (num_pols == 0)
3209                 goto nopol;
3210
3211         if ((flags & XFRM_LOOKUP_ICMP) &&
3212             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3213                 err = -ENOENT;
3214                 goto error;
3215         }
3216
3217         for (i = 0; i < num_pols; i++)
3218                 pols[i]->curlft.use_time = ktime_get_real_seconds();
3219
3220         if (num_xfrms < 0) {
3221                 /* Prohibit the flow */
3222                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3223                 err = -EPERM;
3224                 goto error;
3225         } else if (num_xfrms > 0) {
3226                 /* Flow transformed */
3227                 dst_release(dst_orig);
3228         } else {
3229                 /* Flow passes untransformed */
3230                 dst_release(dst);
3231                 dst = dst_orig;
3232         }
3233 ok:
3234         xfrm_pols_put(pols, drop_pols);
3235         if (dst && dst->xfrm &&
3236             dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3237                 dst->flags |= DST_XFRM_TUNNEL;
3238         return dst;
3239
3240 nopol:
3241         if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3242             net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3243                 err = -EPERM;
3244                 goto error;
3245         }
3246         if (!(flags & XFRM_LOOKUP_ICMP)) {
3247                 dst = dst_orig;
3248                 goto ok;
3249         }
3250         err = -ENOENT;
3251 error:
3252         dst_release(dst);
3253 dropdst:
3254         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3255                 dst_release(dst_orig);
3256         xfrm_pols_put(pols, drop_pols);
3257         return ERR_PTR(err);
3258 }
3259 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3260
3261 /* Main function: finds/creates a bundle for given flow.
3262  *
3263  * At the moment we eat a raw IP route. Mostly to speed up lookups
3264  * on interfaces with disabled IPsec.
3265  */
3266 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3267                               const struct flowi *fl, const struct sock *sk,
3268                               int flags)
3269 {
3270         return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3271 }
3272 EXPORT_SYMBOL(xfrm_lookup);
3273
3274 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3275  * Otherwise we may send out blackholed packets.
3276  */
3277 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3278                                     const struct flowi *fl,
3279                                     const struct sock *sk, int flags)
3280 {
3281         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3282                                             flags | XFRM_LOOKUP_QUEUE |
3283                                             XFRM_LOOKUP_KEEP_DST_REF);
3284
3285         if (PTR_ERR(dst) == -EREMOTE)
3286                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3287
3288         if (IS_ERR(dst))
3289                 dst_release(dst_orig);
3290
3291         return dst;
3292 }
3293 EXPORT_SYMBOL(xfrm_lookup_route);
3294
3295 static inline int
3296 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3297 {
3298         struct sec_path *sp = skb_sec_path(skb);
3299         struct xfrm_state *x;
3300
3301         if (!sp || idx < 0 || idx >= sp->len)
3302                 return 0;
3303         x = sp->xvec[idx];
3304         if (!x->type->reject)
3305                 return 0;
3306         return x->type->reject(x, skb, fl);
3307 }
3308
3309 /* When skb is transformed back to its "native" form, we have to
3310  * check policy restrictions. At the moment we make this in maximally
3311  * stupid way. Shame on me. :-) Of course, connected sockets must
3312  * have policy cached at them.
3313  */
3314
3315 static inline int
3316 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3317               unsigned short family, u32 if_id)
3318 {
3319         if (xfrm_state_kern(x))
3320                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3321         return  x->id.proto == tmpl->id.proto &&
3322                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3323                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3324                 x->props.mode == tmpl->mode &&
3325                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3326                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3327                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3328                   xfrm_state_addr_cmp(tmpl, x, family)) &&
3329                 (if_id == 0 || if_id == x->if_id);
3330 }
3331
3332 /*
3333  * 0 or more than 0 is returned when validation is succeeded (either bypass
3334  * because of optional transport mode, or next index of the matched secpath
3335  * state with the template.
3336  * -1 is returned when no matching template is found.
3337  * Otherwise "-2 - errored_index" is returned.
3338  */
3339 static inline int
3340 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3341                unsigned short family, u32 if_id)
3342 {
3343         int idx = start;
3344
3345         if (tmpl->optional) {
3346                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3347                         return start;
3348         } else
3349                 start = -1;
3350         for (; idx < sp->len; idx++) {
3351                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
3352                         return ++idx;
3353                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3354                         if (idx < sp->verified_cnt) {
3355                                 /* Secpath entry previously verified, consider optional and
3356                                  * continue searching
3357                                  */
3358                                 continue;
3359                         }
3360
3361                         if (start == -1)
3362                                 start = -2-idx;
3363                         break;
3364                 }
3365         }
3366         return start;
3367 }
3368
3369 static void
3370 decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3371 {
3372         const struct iphdr *iph = ip_hdr(skb);
3373         int ihl = iph->ihl;
3374         u8 *xprth = skb_network_header(skb) + ihl * 4;
3375         struct flowi4 *fl4 = &fl->u.ip4;
3376         int oif = 0;
3377
3378         if (skb_dst(skb) && skb_dst(skb)->dev)
3379                 oif = skb_dst(skb)->dev->ifindex;
3380
3381         memset(fl4, 0, sizeof(struct flowi4));
3382         fl4->flowi4_mark = skb->mark;
3383         fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3384
3385         fl4->flowi4_proto = iph->protocol;
3386         fl4->daddr = reverse ? iph->saddr : iph->daddr;
3387         fl4->saddr = reverse ? iph->daddr : iph->saddr;
3388         fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK;
3389
3390         if (!ip_is_fragment(iph)) {
3391                 switch (iph->protocol) {
3392                 case IPPROTO_UDP:
3393                 case IPPROTO_UDPLITE:
3394                 case IPPROTO_TCP:
3395                 case IPPROTO_SCTP:
3396                 case IPPROTO_DCCP:
3397                         if (xprth + 4 < skb->data ||
3398                             pskb_may_pull(skb, xprth + 4 - skb->data)) {
3399                                 __be16 *ports;
3400
3401                                 xprth = skb_network_header(skb) + ihl * 4;
3402                                 ports = (__be16 *)xprth;
3403
3404                                 fl4->fl4_sport = ports[!!reverse];
3405                                 fl4->fl4_dport = ports[!reverse];
3406                         }
3407                         break;
3408                 case IPPROTO_ICMP:
3409                         if (xprth + 2 < skb->data ||
3410                             pskb_may_pull(skb, xprth + 2 - skb->data)) {
3411                                 u8 *icmp;
3412
3413                                 xprth = skb_network_header(skb) + ihl * 4;
3414                                 icmp = xprth;
3415
3416                                 fl4->fl4_icmp_type = icmp[0];
3417                                 fl4->fl4_icmp_code = icmp[1];
3418                         }
3419                         break;
3420                 case IPPROTO_GRE:
3421                         if (xprth + 12 < skb->data ||
3422                             pskb_may_pull(skb, xprth + 12 - skb->data)) {
3423                                 __be16 *greflags;
3424                                 __be32 *gre_hdr;
3425
3426                                 xprth = skb_network_header(skb) + ihl * 4;
3427                                 greflags = (__be16 *)xprth;
3428                                 gre_hdr = (__be32 *)xprth;
3429
3430                                 if (greflags[0] & GRE_KEY) {
3431                                         if (greflags[0] & GRE_CSUM)
3432                                                 gre_hdr++;
3433                                         fl4->fl4_gre_key = gre_hdr[1];
3434                                 }
3435                         }
3436                         break;
3437                 default:
3438                         break;
3439                 }
3440         }
3441 }
3442
3443 #if IS_ENABLED(CONFIG_IPV6)
3444 static void
3445 decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3446 {
3447         struct flowi6 *fl6 = &fl->u.ip6;
3448         int onlyproto = 0;
3449         const struct ipv6hdr *hdr = ipv6_hdr(skb);
3450         u32 offset = sizeof(*hdr);
3451         struct ipv6_opt_hdr *exthdr;
3452         const unsigned char *nh = skb_network_header(skb);
3453         u16 nhoff = IP6CB(skb)->nhoff;
3454         int oif = 0;
3455         u8 nexthdr;
3456
3457         if (!nhoff)
3458                 nhoff = offsetof(struct ipv6hdr, nexthdr);
3459
3460         nexthdr = nh[nhoff];
3461
3462         if (skb_dst(skb) && skb_dst(skb)->dev)
3463                 oif = skb_dst(skb)->dev->ifindex;
3464
3465         memset(fl6, 0, sizeof(struct flowi6));
3466         fl6->flowi6_mark = skb->mark;
3467         fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3468
3469         fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3470         fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
3471
3472         while (nh + offset + sizeof(*exthdr) < skb->data ||
3473                pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3474                 nh = skb_network_header(skb);
3475                 exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3476
3477                 switch (nexthdr) {
3478                 case NEXTHDR_FRAGMENT:
3479                         onlyproto = 1;
3480                         fallthrough;
3481                 case NEXTHDR_ROUTING:
3482                 case NEXTHDR_HOP:
3483                 case NEXTHDR_DEST:
3484                         offset += ipv6_optlen(exthdr);
3485                         nexthdr = exthdr->nexthdr;
3486                         break;
3487                 case IPPROTO_UDP:
3488                 case IPPROTO_UDPLITE:
3489                 case IPPROTO_TCP:
3490                 case IPPROTO_SCTP:
3491                 case IPPROTO_DCCP:
3492                         if (!onlyproto && (nh + offset + 4 < skb->data ||
3493                              pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3494                                 __be16 *ports;
3495
3496                                 nh = skb_network_header(skb);
3497                                 ports = (__be16 *)(nh + offset);
3498                                 fl6->fl6_sport = ports[!!reverse];
3499                                 fl6->fl6_dport = ports[!reverse];
3500                         }
3501                         fl6->flowi6_proto = nexthdr;
3502                         return;
3503                 case IPPROTO_ICMPV6:
3504                         if (!onlyproto && (nh + offset + 2 < skb->data ||
3505                             pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3506                                 u8 *icmp;
3507
3508                                 nh = skb_network_header(skb);
3509                                 icmp = (u8 *)(nh + offset);
3510                                 fl6->fl6_icmp_type = icmp[0];
3511                                 fl6->fl6_icmp_code = icmp[1];
3512                         }
3513                         fl6->flowi6_proto = nexthdr;
3514                         return;
3515                 case IPPROTO_GRE:
3516                         if (!onlyproto &&
3517                             (nh + offset + 12 < skb->data ||
3518                              pskb_may_pull(skb, nh + offset + 12 - skb->data))) {
3519                                 struct gre_base_hdr *gre_hdr;
3520                                 __be32 *gre_key;
3521
3522                                 nh = skb_network_header(skb);
3523                                 gre_hdr = (struct gre_base_hdr *)(nh + offset);
3524                                 gre_key = (__be32 *)(gre_hdr + 1);
3525
3526                                 if (gre_hdr->flags & GRE_KEY) {
3527                                         if (gre_hdr->flags & GRE_CSUM)
3528                                                 gre_key++;
3529                                         fl6->fl6_gre_key = *gre_key;
3530                                 }
3531                         }
3532                         fl6->flowi6_proto = nexthdr;
3533                         return;
3534
3535 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3536                 case IPPROTO_MH:
3537                         offset += ipv6_optlen(exthdr);
3538                         if (!onlyproto && (nh + offset + 3 < skb->data ||
3539                             pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3540                                 struct ip6_mh *mh;
3541
3542                                 nh = skb_network_header(skb);
3543                                 mh = (struct ip6_mh *)(nh + offset);
3544                                 fl6->fl6_mh_type = mh->ip6mh_type;
3545                         }
3546                         fl6->flowi6_proto = nexthdr;
3547                         return;
3548 #endif
3549                 default:
3550                         fl6->flowi6_proto = nexthdr;
3551                         return;
3552                 }
3553         }
3554 }
3555 #endif
3556
3557 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3558                           unsigned int family, int reverse)
3559 {
3560         switch (family) {
3561         case AF_INET:
3562                 decode_session4(skb, fl, reverse);
3563                 break;
3564 #if IS_ENABLED(CONFIG_IPV6)
3565         case AF_INET6:
3566                 decode_session6(skb, fl, reverse);
3567                 break;
3568 #endif
3569         default:
3570                 return -EAFNOSUPPORT;
3571         }
3572
3573         return security_xfrm_decode_session(skb, &fl->flowi_secid);
3574 }
3575 EXPORT_SYMBOL(__xfrm_decode_session);
3576
3577 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3578 {
3579         for (; k < sp->len; k++) {
3580                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3581                         *idxp = k;
3582                         return 1;
3583                 }
3584         }
3585
3586         return 0;
3587 }
3588
3589 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3590                         unsigned short family)
3591 {
3592         struct net *net = dev_net(skb->dev);
3593         struct xfrm_policy *pol;
3594         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3595         int npols = 0;
3596         int xfrm_nr;
3597         int pi;
3598         int reverse;
3599         struct flowi fl;
3600         int xerr_idx = -1;
3601         const struct xfrm_if_cb *ifcb;
3602         struct sec_path *sp;
3603         u32 if_id = 0;
3604
3605         rcu_read_lock();
3606         ifcb = xfrm_if_get_cb();
3607
3608         if (ifcb) {
3609                 struct xfrm_if_decode_session_result r;
3610
3611                 if (ifcb->decode_session(skb, family, &r)) {
3612                         if_id = r.if_id;
3613                         net = r.net;
3614                 }
3615         }
3616         rcu_read_unlock();
3617
3618         reverse = dir & ~XFRM_POLICY_MASK;
3619         dir &= XFRM_POLICY_MASK;
3620
3621         if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3622                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3623                 return 0;
3624         }
3625
3626         nf_nat_decode_session(skb, &fl, family);
3627
3628         /* First, check used SA against their selectors. */
3629         sp = skb_sec_path(skb);
3630         if (sp) {
3631                 int i;
3632
3633                 for (i = sp->len - 1; i >= 0; i--) {
3634                         struct xfrm_state *x = sp->xvec[i];
3635                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
3636                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3637                                 return 0;
3638                         }
3639                 }
3640         }
3641
3642         pol = NULL;
3643         sk = sk_to_full_sk(sk);
3644         if (sk && sk->sk_policy[dir]) {
3645                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3646                 if (IS_ERR(pol)) {
3647                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3648                         return 0;
3649                 }
3650         }
3651
3652         if (!pol)
3653                 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3654
3655         if (IS_ERR(pol)) {
3656                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3657                 return 0;
3658         }
3659
3660         if (!pol) {
3661                 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3662                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3663                         return 0;
3664                 }
3665
3666                 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3667                         xfrm_secpath_reject(xerr_idx, skb, &fl);
3668                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3669                         return 0;
3670                 }
3671                 return 1;
3672         }
3673
3674         /* This lockless write can happen from different cpus. */
3675         WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
3676
3677         pols[0] = pol;
3678         npols++;
3679 #ifdef CONFIG_XFRM_SUB_POLICY
3680         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3681                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3682                                                     &fl, family,
3683                                                     XFRM_POLICY_IN, if_id);
3684                 if (pols[1]) {
3685                         if (IS_ERR(pols[1])) {
3686                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3687                                 xfrm_pol_put(pols[0]);
3688                                 return 0;
3689                         }
3690                         /* This write can happen from different cpus. */
3691                         WRITE_ONCE(pols[1]->curlft.use_time,
3692                                    ktime_get_real_seconds());
3693                         npols++;
3694                 }
3695         }
3696 #endif
3697
3698         if (pol->action == XFRM_POLICY_ALLOW) {
3699                 static struct sec_path dummy;
3700                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3701                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3702                 struct xfrm_tmpl **tpp = tp;
3703                 int ti = 0;
3704                 int i, k;
3705
3706                 sp = skb_sec_path(skb);
3707                 if (!sp)
3708                         sp = &dummy;
3709
3710                 for (pi = 0; pi < npols; pi++) {
3711                         if (pols[pi] != pol &&
3712                             pols[pi]->action != XFRM_POLICY_ALLOW) {
3713                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3714                                 goto reject;
3715                         }
3716                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3717                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3718                                 goto reject_error;
3719                         }
3720                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
3721                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3722                 }
3723                 xfrm_nr = ti;
3724
3725                 if (npols > 1) {
3726                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3727                         tpp = stp;
3728                 }
3729
3730                 /* For each tunnel xfrm, find the first matching tmpl.
3731                  * For each tmpl before that, find corresponding xfrm.
3732                  * Order is _important_. Later we will implement
3733                  * some barriers, but at the moment barriers
3734                  * are implied between each two transformations.
3735                  * Upon success, marks secpath entries as having been
3736                  * verified to allow them to be skipped in future policy
3737                  * checks (e.g. nested tunnels).
3738                  */
3739                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3740                         k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
3741                         if (k < 0) {
3742                                 if (k < -1)
3743                                         /* "-2 - errored_index" returned */
3744                                         xerr_idx = -(2+k);
3745                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3746                                 goto reject;
3747                         }
3748                 }
3749
3750                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3751                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3752                         goto reject;
3753                 }
3754
3755                 xfrm_pols_put(pols, npols);
3756                 sp->verified_cnt = k;
3757
3758                 return 1;
3759         }
3760         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3761
3762 reject:
3763         xfrm_secpath_reject(xerr_idx, skb, &fl);
3764 reject_error:
3765         xfrm_pols_put(pols, npols);
3766         return 0;
3767 }
3768 EXPORT_SYMBOL(__xfrm_policy_check);
3769
3770 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3771 {
3772         struct net *net = dev_net(skb->dev);
3773         struct flowi fl;
3774         struct dst_entry *dst;
3775         int res = 1;
3776
3777         if (xfrm_decode_session(skb, &fl, family) < 0) {
3778                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3779                 return 0;
3780         }
3781
3782         skb_dst_force(skb);
3783         if (!skb_dst(skb)) {
3784                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3785                 return 0;
3786         }
3787
3788         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3789         if (IS_ERR(dst)) {
3790                 res = 0;
3791                 dst = NULL;
3792         }
3793         skb_dst_set(skb, dst);
3794         return res;
3795 }
3796 EXPORT_SYMBOL(__xfrm_route_forward);
3797
3798 /* Optimize later using cookies and generation ids. */
3799
3800 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3801 {
3802         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3803          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3804          * get validated by dst_ops->check on every use.  We do this
3805          * because when a normal route referenced by an XFRM dst is
3806          * obsoleted we do not go looking around for all parent
3807          * referencing XFRM dsts so that we can invalidate them.  It
3808          * is just too much work.  Instead we make the checks here on
3809          * every use.  For example:
3810          *
3811          *      XFRM dst A --> IPv4 dst X
3812          *
3813          * X is the "xdst->route" of A (X is also the "dst->path" of A
3814          * in this example).  If X is marked obsolete, "A" will not
3815          * notice.  That's what we are validating here via the
3816          * stale_bundle() check.
3817          *
3818          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3819          * be marked on it.
3820          * This will force stale_bundle() to fail on any xdst bundle with
3821          * this dst linked in it.
3822          */
3823         if (dst->obsolete < 0 && !stale_bundle(dst))
3824                 return dst;
3825
3826         return NULL;
3827 }
3828
3829 static int stale_bundle(struct dst_entry *dst)
3830 {
3831         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3832 }
3833
3834 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3835 {
3836         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3837                 dst->dev = blackhole_netdev;
3838                 dev_hold(dst->dev);
3839                 dev_put(dev);
3840         }
3841 }
3842 EXPORT_SYMBOL(xfrm_dst_ifdown);
3843
3844 static void xfrm_link_failure(struct sk_buff *skb)
3845 {
3846         /* Impossible. Such dst must be popped before reaches point of failure. */
3847 }
3848
3849 static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3850 {
3851         if (dst) {
3852                 if (dst->obsolete) {
3853                         dst_release(dst);
3854                         dst = NULL;
3855                 }
3856         }
3857         return dst;
3858 }
3859
3860 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3861 {
3862         while (nr--) {
3863                 struct xfrm_dst *xdst = bundle[nr];
3864                 u32 pmtu, route_mtu_cached;
3865                 struct dst_entry *dst;
3866
3867                 dst = &xdst->u.dst;
3868                 pmtu = dst_mtu(xfrm_dst_child(dst));
3869                 xdst->child_mtu_cached = pmtu;
3870
3871                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3872
3873                 route_mtu_cached = dst_mtu(xdst->route);
3874                 xdst->route_mtu_cached = route_mtu_cached;
3875
3876                 if (pmtu > route_mtu_cached)
3877                         pmtu = route_mtu_cached;
3878
3879                 dst_metric_set(dst, RTAX_MTU, pmtu);
3880         }
3881 }
3882
3883 /* Check that the bundle accepts the flow and its components are
3884  * still valid.
3885  */
3886
3887 static int xfrm_bundle_ok(struct xfrm_dst *first)
3888 {
3889         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3890         struct dst_entry *dst = &first->u.dst;
3891         struct xfrm_dst *xdst;
3892         int start_from, nr;
3893         u32 mtu;
3894
3895         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3896             (dst->dev && !netif_running(dst->dev)))
3897                 return 0;
3898
3899         if (dst->flags & DST_XFRM_QUEUE)
3900                 return 1;
3901
3902         start_from = nr = 0;
3903         do {
3904                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3905
3906                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
3907                         return 0;
3908                 if (xdst->xfrm_genid != dst->xfrm->genid)
3909                         return 0;
3910                 if (xdst->num_pols > 0 &&
3911                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3912                         return 0;
3913
3914                 bundle[nr++] = xdst;
3915
3916                 mtu = dst_mtu(xfrm_dst_child(dst));
3917                 if (xdst->child_mtu_cached != mtu) {
3918                         start_from = nr;
3919                         xdst->child_mtu_cached = mtu;
3920                 }
3921
3922                 if (!dst_check(xdst->route, xdst->route_cookie))
3923                         return 0;
3924                 mtu = dst_mtu(xdst->route);
3925                 if (xdst->route_mtu_cached != mtu) {
3926                         start_from = nr;
3927                         xdst->route_mtu_cached = mtu;
3928                 }
3929
3930                 dst = xfrm_dst_child(dst);
3931         } while (dst->xfrm);
3932
3933         if (likely(!start_from))
3934                 return 1;
3935
3936         xdst = bundle[start_from - 1];
3937         mtu = xdst->child_mtu_cached;
3938         while (start_from--) {
3939                 dst = &xdst->u.dst;
3940
3941                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
3942                 if (mtu > xdst->route_mtu_cached)
3943                         mtu = xdst->route_mtu_cached;
3944                 dst_metric_set(dst, RTAX_MTU, mtu);
3945                 if (!start_from)
3946                         break;
3947
3948                 xdst = bundle[start_from - 1];
3949                 xdst->child_mtu_cached = mtu;
3950         }
3951
3952         return 1;
3953 }
3954
3955 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3956 {
3957         return dst_metric_advmss(xfrm_dst_path(dst));
3958 }
3959
3960 static unsigned int xfrm_mtu(const struct dst_entry *dst)
3961 {
3962         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3963
3964         return mtu ? : dst_mtu(xfrm_dst_path(dst));
3965 }
3966
3967 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3968                                         const void *daddr)
3969 {
3970         while (dst->xfrm) {
3971                 const struct xfrm_state *xfrm = dst->xfrm;
3972
3973                 dst = xfrm_dst_child(dst);
3974
3975                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3976                         continue;
3977                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3978                         daddr = xfrm->coaddr;
3979                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3980                         daddr = &xfrm->id.daddr;
3981         }
3982         return daddr;
3983 }
3984
3985 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3986                                            struct sk_buff *skb,
3987                                            const void *daddr)
3988 {
3989         const struct dst_entry *path = xfrm_dst_path(dst);
3990
3991         if (!skb)
3992                 daddr = xfrm_get_dst_nexthop(dst, daddr);
3993         return path->ops->neigh_lookup(path, skb, daddr);
3994 }
3995
3996 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3997 {
3998         const struct dst_entry *path = xfrm_dst_path(dst);
3999
4000         daddr = xfrm_get_dst_nexthop(dst, daddr);
4001         path->ops->confirm_neigh(path, daddr);
4002 }
4003
4004 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
4005 {
4006         int err = 0;
4007
4008         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
4009                 return -EAFNOSUPPORT;
4010
4011         spin_lock(&xfrm_policy_afinfo_lock);
4012         if (unlikely(xfrm_policy_afinfo[family] != NULL))
4013                 err = -EEXIST;
4014         else {
4015                 struct dst_ops *dst_ops = afinfo->dst_ops;
4016                 if (likely(dst_ops->kmem_cachep == NULL))
4017                         dst_ops->kmem_cachep = xfrm_dst_cache;
4018                 if (likely(dst_ops->check == NULL))
4019                         dst_ops->check = xfrm_dst_check;
4020                 if (likely(dst_ops->default_advmss == NULL))
4021                         dst_ops->default_advmss = xfrm_default_advmss;
4022                 if (likely(dst_ops->mtu == NULL))
4023                         dst_ops->mtu = xfrm_mtu;
4024                 if (likely(dst_ops->negative_advice == NULL))
4025                         dst_ops->negative_advice = xfrm_negative_advice;
4026                 if (likely(dst_ops->link_failure == NULL))
4027                         dst_ops->link_failure = xfrm_link_failure;
4028                 if (likely(dst_ops->neigh_lookup == NULL))
4029                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
4030                 if (likely(!dst_ops->confirm_neigh))
4031                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
4032                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
4033         }
4034         spin_unlock(&xfrm_policy_afinfo_lock);
4035
4036         return err;
4037 }
4038 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
4039
4040 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
4041 {
4042         struct dst_ops *dst_ops = afinfo->dst_ops;
4043         int i;
4044
4045         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
4046                 if (xfrm_policy_afinfo[i] != afinfo)
4047                         continue;
4048                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
4049                 break;
4050         }
4051
4052         synchronize_rcu();
4053
4054         dst_ops->kmem_cachep = NULL;
4055         dst_ops->check = NULL;
4056         dst_ops->negative_advice = NULL;
4057         dst_ops->link_failure = NULL;
4058 }
4059 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
4060
4061 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
4062 {
4063         spin_lock(&xfrm_if_cb_lock);
4064         rcu_assign_pointer(xfrm_if_cb, ifcb);
4065         spin_unlock(&xfrm_if_cb_lock);
4066 }
4067 EXPORT_SYMBOL(xfrm_if_register_cb);
4068
4069 void xfrm_if_unregister_cb(void)
4070 {
4071         RCU_INIT_POINTER(xfrm_if_cb, NULL);
4072         synchronize_rcu();
4073 }
4074 EXPORT_SYMBOL(xfrm_if_unregister_cb);
4075
4076 #ifdef CONFIG_XFRM_STATISTICS
4077 static int __net_init xfrm_statistics_init(struct net *net)
4078 {
4079         int rv;
4080         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
4081         if (!net->mib.xfrm_statistics)
4082                 return -ENOMEM;
4083         rv = xfrm_proc_init(net);
4084         if (rv < 0)
4085                 free_percpu(net->mib.xfrm_statistics);
4086         return rv;
4087 }
4088
4089 static void xfrm_statistics_fini(struct net *net)
4090 {
4091         xfrm_proc_fini(net);
4092         free_percpu(net->mib.xfrm_statistics);
4093 }
4094 #else
4095 static int __net_init xfrm_statistics_init(struct net *net)
4096 {
4097         return 0;
4098 }
4099
4100 static void xfrm_statistics_fini(struct net *net)
4101 {
4102 }
4103 #endif
4104
4105 static int __net_init xfrm_policy_init(struct net *net)
4106 {
4107         unsigned int hmask, sz;
4108         int dir, err;
4109
4110         if (net_eq(net, &init_net)) {
4111                 xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4112                                            sizeof(struct xfrm_dst),
4113                                            0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4114                                            NULL);
4115                 err = rhashtable_init(&xfrm_policy_inexact_table,
4116                                       &xfrm_pol_inexact_params);
4117                 BUG_ON(err);
4118         }
4119
4120         hmask = 8 - 1;
4121         sz = (hmask+1) * sizeof(struct hlist_head);
4122
4123         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4124         if (!net->xfrm.policy_byidx)
4125                 goto out_byidx;
4126         net->xfrm.policy_idx_hmask = hmask;
4127
4128         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4129                 struct xfrm_policy_hash *htab;
4130
4131                 net->xfrm.policy_count[dir] = 0;
4132                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4133                 INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4134
4135                 htab = &net->xfrm.policy_bydst[dir];
4136                 htab->table = xfrm_hash_alloc(sz);
4137                 if (!htab->table)
4138                         goto out_bydst;
4139                 htab->hmask = hmask;
4140                 htab->dbits4 = 32;
4141                 htab->sbits4 = 32;
4142                 htab->dbits6 = 128;
4143                 htab->sbits6 = 128;
4144         }
4145         net->xfrm.policy_hthresh.lbits4 = 32;
4146         net->xfrm.policy_hthresh.rbits4 = 32;
4147         net->xfrm.policy_hthresh.lbits6 = 128;
4148         net->xfrm.policy_hthresh.rbits6 = 128;
4149
4150         seqlock_init(&net->xfrm.policy_hthresh.lock);
4151
4152         INIT_LIST_HEAD(&net->xfrm.policy_all);
4153         INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4154         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4155         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4156         return 0;
4157
4158 out_bydst:
4159         for (dir--; dir >= 0; dir--) {
4160                 struct xfrm_policy_hash *htab;
4161
4162                 htab = &net->xfrm.policy_bydst[dir];
4163                 xfrm_hash_free(htab->table, sz);
4164         }
4165         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4166 out_byidx:
4167         return -ENOMEM;
4168 }
4169
4170 static void xfrm_policy_fini(struct net *net)
4171 {
4172         struct xfrm_pol_inexact_bin *b, *t;
4173         unsigned int sz;
4174         int dir;
4175
4176         flush_work(&net->xfrm.policy_hash_work);
4177 #ifdef CONFIG_XFRM_SUB_POLICY
4178         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4179 #endif
4180         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4181
4182         WARN_ON(!list_empty(&net->xfrm.policy_all));
4183
4184         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4185                 struct xfrm_policy_hash *htab;
4186
4187                 WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4188
4189                 htab = &net->xfrm.policy_bydst[dir];
4190                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4191                 WARN_ON(!hlist_empty(htab->table));
4192                 xfrm_hash_free(htab->table, sz);
4193         }
4194
4195         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4196         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4197         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4198
4199         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4200         list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4201                 __xfrm_policy_inexact_prune_bin(b, true);
4202         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4203 }
4204
4205 static int __net_init xfrm_net_init(struct net *net)
4206 {
4207         int rv;
4208
4209         /* Initialize the per-net locks here */
4210         spin_lock_init(&net->xfrm.xfrm_state_lock);
4211         spin_lock_init(&net->xfrm.xfrm_policy_lock);
4212         seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4213         mutex_init(&net->xfrm.xfrm_cfg_mutex);
4214         net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4215         net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4216         net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4217
4218         rv = xfrm_statistics_init(net);
4219         if (rv < 0)
4220                 goto out_statistics;
4221         rv = xfrm_state_init(net);
4222         if (rv < 0)
4223                 goto out_state;
4224         rv = xfrm_policy_init(net);
4225         if (rv < 0)
4226                 goto out_policy;
4227         rv = xfrm_sysctl_init(net);
4228         if (rv < 0)
4229                 goto out_sysctl;
4230
4231         return 0;
4232
4233 out_sysctl:
4234         xfrm_policy_fini(net);
4235 out_policy:
4236         xfrm_state_fini(net);
4237 out_state:
4238         xfrm_statistics_fini(net);
4239 out_statistics:
4240         return rv;
4241 }
4242
4243 static void __net_exit xfrm_net_exit(struct net *net)
4244 {
4245         xfrm_sysctl_fini(net);
4246         xfrm_policy_fini(net);
4247         xfrm_state_fini(net);
4248         xfrm_statistics_fini(net);
4249 }
4250
4251 static struct pernet_operations __net_initdata xfrm_net_ops = {
4252         .init = xfrm_net_init,
4253         .exit = xfrm_net_exit,
4254 };
4255
4256 void __init xfrm_init(void)
4257 {
4258         register_pernet_subsys(&xfrm_net_ops);
4259         xfrm_dev_init();
4260         xfrm_input_init();
4261
4262 #ifdef CONFIG_XFRM_ESPINTCP
4263         espintcp_init();
4264 #endif
4265 }
4266
4267 #ifdef CONFIG_AUDITSYSCALL
4268 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4269                                          struct audit_buffer *audit_buf)
4270 {
4271         struct xfrm_sec_ctx *ctx = xp->security;
4272         struct xfrm_selector *sel = &xp->selector;
4273
4274         if (ctx)
4275                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4276                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4277
4278         switch (sel->family) {
4279         case AF_INET:
4280                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4281                 if (sel->prefixlen_s != 32)
4282                         audit_log_format(audit_buf, " src_prefixlen=%d",
4283                                          sel->prefixlen_s);
4284                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4285                 if (sel->prefixlen_d != 32)
4286                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4287                                          sel->prefixlen_d);
4288                 break;
4289         case AF_INET6:
4290                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4291                 if (sel->prefixlen_s != 128)
4292                         audit_log_format(audit_buf, " src_prefixlen=%d",
4293                                          sel->prefixlen_s);
4294                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4295                 if (sel->prefixlen_d != 128)
4296                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4297                                          sel->prefixlen_d);
4298                 break;
4299         }
4300 }
4301
4302 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4303 {
4304         struct audit_buffer *audit_buf;
4305
4306         audit_buf = xfrm_audit_start("SPD-add");
4307         if (audit_buf == NULL)
4308                 return;
4309         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4310         audit_log_format(audit_buf, " res=%u", result);
4311         xfrm_audit_common_policyinfo(xp, audit_buf);
4312         audit_log_end(audit_buf);
4313 }
4314 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4315
4316 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4317                               bool task_valid)
4318 {
4319         struct audit_buffer *audit_buf;
4320
4321         audit_buf = xfrm_audit_start("SPD-delete");
4322         if (audit_buf == NULL)
4323                 return;
4324         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4325         audit_log_format(audit_buf, " res=%u", result);
4326         xfrm_audit_common_policyinfo(xp, audit_buf);
4327         audit_log_end(audit_buf);
4328 }
4329 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4330 #endif
4331
4332 #ifdef CONFIG_XFRM_MIGRATE
4333 static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4334                                         const struct xfrm_selector *sel_tgt)
4335 {
4336         if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4337                 if (sel_tgt->family == sel_cmp->family &&
4338                     xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4339                                     sel_cmp->family) &&
4340                     xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4341                                     sel_cmp->family) &&
4342                     sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4343                     sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4344                         return true;
4345                 }
4346         } else {
4347                 if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4348                         return true;
4349                 }
4350         }
4351         return false;
4352 }
4353
4354 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4355                                                     u8 dir, u8 type, struct net *net, u32 if_id)
4356 {
4357         struct xfrm_policy *pol, *ret = NULL;
4358         struct hlist_head *chain;
4359         u32 priority = ~0U;
4360
4361         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4362         chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4363         hlist_for_each_entry(pol, chain, bydst) {
4364                 if ((if_id == 0 || pol->if_id == if_id) &&
4365                     xfrm_migrate_selector_match(sel, &pol->selector) &&
4366                     pol->type == type) {
4367                         ret = pol;
4368                         priority = ret->priority;
4369                         break;
4370                 }
4371         }
4372         chain = &net->xfrm.policy_inexact[dir];
4373         hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4374                 if ((pol->priority >= priority) && ret)
4375                         break;
4376
4377                 if ((if_id == 0 || pol->if_id == if_id) &&
4378                     xfrm_migrate_selector_match(sel, &pol->selector) &&
4379                     pol->type == type) {
4380                         ret = pol;
4381                         break;
4382                 }
4383         }
4384
4385         xfrm_pol_hold(ret);
4386
4387         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4388
4389         return ret;
4390 }
4391
4392 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4393 {
4394         int match = 0;
4395
4396         if (t->mode == m->mode && t->id.proto == m->proto &&
4397             (m->reqid == 0 || t->reqid == m->reqid)) {
4398                 switch (t->mode) {
4399                 case XFRM_MODE_TUNNEL:
4400                 case XFRM_MODE_BEET:
4401                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4402                                             m->old_family) &&
4403                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
4404                                             m->old_family)) {
4405                                 match = 1;
4406                         }
4407                         break;
4408                 case XFRM_MODE_TRANSPORT:
4409                         /* in case of transport mode, template does not store
4410                            any IP addresses, hence we just compare mode and
4411                            protocol */
4412                         match = 1;
4413                         break;
4414                 default:
4415                         break;
4416                 }
4417         }
4418         return match;
4419 }
4420
4421 /* update endpoint address(es) of template(s) */
4422 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4423                                struct xfrm_migrate *m, int num_migrate,
4424                                struct netlink_ext_ack *extack)
4425 {
4426         struct xfrm_migrate *mp;
4427         int i, j, n = 0;
4428
4429         write_lock_bh(&pol->lock);
4430         if (unlikely(pol->walk.dead)) {
4431                 /* target policy has been deleted */
4432                 NL_SET_ERR_MSG(extack, "Target policy not found");
4433                 write_unlock_bh(&pol->lock);
4434                 return -ENOENT;
4435         }
4436
4437         for (i = 0; i < pol->xfrm_nr; i++) {
4438                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4439                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4440                                 continue;
4441                         n++;
4442                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4443                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4444                                 continue;
4445                         /* update endpoints */
4446                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4447                                sizeof(pol->xfrm_vec[i].id.daddr));
4448                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4449                                sizeof(pol->xfrm_vec[i].saddr));
4450                         pol->xfrm_vec[i].encap_family = mp->new_family;
4451                         /* flush bundles */
4452                         atomic_inc(&pol->genid);
4453                 }
4454         }
4455
4456         write_unlock_bh(&pol->lock);
4457
4458         if (!n)
4459                 return -ENODATA;
4460
4461         return 0;
4462 }
4463
4464 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
4465                               struct netlink_ext_ack *extack)
4466 {
4467         int i, j;
4468
4469         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
4470                 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
4471                 return -EINVAL;
4472         }
4473
4474         for (i = 0; i < num_migrate; i++) {
4475                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4476                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
4477                         NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
4478                         return -EINVAL;
4479                 }
4480
4481                 /* check if there is any duplicated entry */
4482                 for (j = i + 1; j < num_migrate; j++) {
4483                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4484                                     sizeof(m[i].old_daddr)) &&
4485                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4486                                     sizeof(m[i].old_saddr)) &&
4487                             m[i].proto == m[j].proto &&
4488                             m[i].mode == m[j].mode &&
4489                             m[i].reqid == m[j].reqid &&
4490                             m[i].old_family == m[j].old_family) {
4491                                 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
4492                                 return -EINVAL;
4493                         }
4494                 }
4495         }
4496
4497         return 0;
4498 }
4499
4500 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4501                  struct xfrm_migrate *m, int num_migrate,
4502                  struct xfrm_kmaddress *k, struct net *net,
4503                  struct xfrm_encap_tmpl *encap, u32 if_id,
4504                  struct netlink_ext_ack *extack)
4505 {
4506         int i, err, nx_cur = 0, nx_new = 0;
4507         struct xfrm_policy *pol = NULL;
4508         struct xfrm_state *x, *xc;
4509         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4510         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4511         struct xfrm_migrate *mp;
4512
4513         /* Stage 0 - sanity checks */
4514         err = xfrm_migrate_check(m, num_migrate, extack);
4515         if (err < 0)
4516                 goto out;
4517
4518         if (dir >= XFRM_POLICY_MAX) {
4519                 NL_SET_ERR_MSG(extack, "Invalid policy direction");
4520                 err = -EINVAL;
4521                 goto out;
4522         }
4523
4524         /* Stage 1 - find policy */
4525         pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
4526         if (!pol) {
4527                 NL_SET_ERR_MSG(extack, "Target policy not found");
4528                 err = -ENOENT;
4529                 goto out;
4530         }
4531
4532         /* Stage 2 - find and update state(s) */
4533         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4534                 if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4535                         x_cur[nx_cur] = x;
4536                         nx_cur++;
4537                         xc = xfrm_state_migrate(x, mp, encap);
4538                         if (xc) {
4539                                 x_new[nx_new] = xc;
4540                                 nx_new++;
4541                         } else {
4542                                 err = -ENODATA;
4543                                 goto restore_state;
4544                         }
4545                 }
4546         }
4547
4548         /* Stage 3 - update policy */
4549         err = xfrm_policy_migrate(pol, m, num_migrate, extack);
4550         if (err < 0)
4551                 goto restore_state;
4552
4553         /* Stage 4 - delete old state(s) */
4554         if (nx_cur) {
4555                 xfrm_states_put(x_cur, nx_cur);
4556                 xfrm_states_delete(x_cur, nx_cur);
4557         }
4558
4559         /* Stage 5 - announce */
4560         km_migrate(sel, dir, type, m, num_migrate, k, encap);
4561
4562         xfrm_pol_put(pol);
4563
4564         return 0;
4565 out:
4566         return err;
4567
4568 restore_state:
4569         if (pol)
4570                 xfrm_pol_put(pol);
4571         if (nx_cur)
4572                 xfrm_states_put(x_cur, nx_cur);
4573         if (nx_new)
4574                 xfrm_states_delete(x_new, nx_new);
4575
4576         return err;
4577 }
4578 EXPORT_SYMBOL(xfrm_migrate);
4579 #endif