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 <linux/icmp.h>
  33 #include <net/dst.h>
  34 #include <net/flow.h>
  35 #include <net/inet_ecn.h>
  36 #include <net/xfrm.h>
  37 #include <net/ip.h>
  38 #include <net/gre.h>
  39 #if IS_ENABLED(CONFIG_IPV6_MIP6)
  40 #include <net/mip6.h>
  41 #endif
  42 #ifdef CONFIG_XFRM_STATISTICS
  43 #include <net/snmp.h>
  44 #endif
  45 #ifdef CONFIG_XFRM_ESPINTCP
  46 #include <net/espintcp.h>
  47 #endif
  48 #include <net/inet_dscp.h>
  49
  50 #include "xfrm_hash.h"
  51
  52 #define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  53 #define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  54 #define XFRM_MAX_QUEUE_LEN      100
  55
  56 struct xfrm_flo {
  57         struct dst_entry *dst_orig;
  58         u8 flags;
  59 };
  60
  61 /* prefixes smaller than this are stored in lists, not trees. */
  62 #define INEXACT_PREFIXLEN_IPV4  16
  63 #define INEXACT_PREFIXLEN_IPV6  48
  64
  65 struct xfrm_pol_inexact_node {
  66         struct rb_node node;
  67         union {
  68                 xfrm_address_t addr;
  69                 struct rcu_head rcu;
  70         };
  71         u8 prefixlen;
  72
  73         struct rb_root root;
  74
  75         /* the policies matching this node, can be empty list */
  76         struct hlist_head hhead;
  77 };
  78
  79 /* xfrm inexact policy search tree:
  80  * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
  81  *  |
  82  * +---- root_d: sorted by daddr:prefix
  83  * |                 |
  84  * |        xfrm_pol_inexact_node
  85  * |                 |
  86  * |                 +- root: sorted by saddr/prefix
  87  * |                 |              |
  88  * |                 |         xfrm_pol_inexact_node
  89  * |                 |              |
  90  * |                 |              + root: unused
  91  * |                 |              |
  92  * |                 |              + hhead: saddr:daddr policies
  93  * |                 |
  94  * |                 +- coarse policies and all any:daddr policies
  95  * |
  96  * +---- root_s: sorted by saddr:prefix
  97  * |                 |
  98  * |        xfrm_pol_inexact_node
  99  * |                 |
 100  * |                 + root: unused
 101  * |                 |
 102  * |                 + hhead: saddr:any policies
 103  * |
 104  * +---- coarse policies and all any:any policies
 105  *
 106  * Lookups return four candidate lists:
 107  * 1. any:any list from top-level xfrm_pol_inexact_bin
 108  * 2. any:daddr list from daddr tree
 109  * 3. saddr:daddr list from 2nd level daddr tree
 110  * 4. saddr:any list from saddr tree
 111  *
 112  * This result set then needs to be searched for the policy with
 113  * the lowest priority.  If two candidates have the same priority, the
 114  * struct xfrm_policy pos member with the lower number is used.
 115  *
 116  * This replicates previous single-list-search algorithm which would
 117  * return first matching policy in the (ordered-by-priority) list.
 118  */
 119
 120 struct xfrm_pol_inexact_key {
 121         possible_net_t net;
 122         u32 if_id;
 123         u16 family;
 124         u8 dir, type;
 125 };
 126
 127 struct xfrm_pol_inexact_bin {
 128         struct xfrm_pol_inexact_key k;
 129         struct rhash_head head;
 130         /* list containing '*:*' policies */
 131         struct hlist_head hhead;
 132
 133         seqcount_spinlock_t count;
 134         /* tree sorted by daddr/prefix */
 135         struct rb_root root_d;
 136
 137         /* tree sorted by saddr/prefix */
 138         struct rb_root root_s;
 139
 140         /* slow path below */
 141         struct list_head inexact_bins;
 142         struct rcu_head rcu;
 143 };
 144
 145 enum xfrm_pol_inexact_candidate_type {
 146         XFRM_POL_CAND_BOTH,
 147         XFRM_POL_CAND_SADDR,
 148         XFRM_POL_CAND_DADDR,
 149         XFRM_POL_CAND_ANY,
 150
 151         XFRM_POL_CAND_MAX,
 152 };
 153
 154 struct xfrm_pol_inexact_candidates {
 155         struct hlist_head *res[XFRM_POL_CAND_MAX];
 156 };
 157
 158 struct xfrm_flow_keys {
 159         struct flow_dissector_key_basic basic;
 160         struct flow_dissector_key_control control;
 161         union {
 162                 struct flow_dissector_key_ipv4_addrs ipv4;
 163                 struct flow_dissector_key_ipv6_addrs ipv6;
 164         } addrs;
 165         struct flow_dissector_key_ip ip;
 166         struct flow_dissector_key_icmp icmp;
 167         struct flow_dissector_key_ports ports;
 168         struct flow_dissector_key_keyid gre;
 169 };
 170
 171 static struct flow_dissector xfrm_session_dissector __ro_after_init;
 172
 173 static DEFINE_SPINLOCK(xfrm_if_cb_lock);
 174 static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
 175
 176 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
 177 static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 178                                                 __read_mostly;
 179
 180 static struct kmem_cache *xfrm_dst_cache __ro_after_init;
 181
 182 static struct rhashtable xfrm_policy_inexact_table;
 183 static const struct rhashtable_params xfrm_pol_inexact_params;
 184
 185 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
 186 static int stale_bundle(struct dst_entry *dst);
 187 static int xfrm_bundle_ok(struct xfrm_dst *xdst);
 188 static void xfrm_policy_queue_process(struct timer_list *t);
 189
 190 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 191 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 192                                                 int dir);
 193
 194 static struct xfrm_pol_inexact_bin *
 195 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
 196                            u32 if_id);
 197
 198 static struct xfrm_pol_inexact_bin *
 199 xfrm_policy_inexact_lookup_rcu(struct net *net,
 200                                u8 type, u16 family, u8 dir, u32 if_id);
 201 static struct xfrm_policy *
 202 xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
 203                         bool excl);
 204
 205 static bool
 206 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
 207                                     struct xfrm_pol_inexact_bin *b,
 208                                     const xfrm_address_t *saddr,
 209                                     const xfrm_address_t *daddr);
 210
 211 static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
 212 {
 213         return refcount_inc_not_zero(&policy->refcnt);
 214 }
 215
 216 static inline bool
 217 __xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 218 {
 219         const struct flowi4 *fl4 = &fl->u.ip4;
 220
 221         return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
 222                 addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
 223                 !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
 224                 !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
 225                 (fl4->flowi4_proto == sel->proto || !sel->proto) &&
 226                 (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 227 }
 228
 229 static inline bool
 230 __xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 231 {
 232         const struct flowi6 *fl6 = &fl->u.ip6;
 233
 234         return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
 235                 addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
 236                 !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
 237                 !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
 238                 (fl6->flowi6_proto == sel->proto || !sel->proto) &&
 239                 (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 240 }
 241
 242 bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
 243                          unsigned short family)
 244 {
 245         switch (family) {
 246         case AF_INET:
 247                 return __xfrm4_selector_match(sel, fl);
 248         case AF_INET6:
 249                 return __xfrm6_selector_match(sel, fl);
 250         }
 251         return false;
 252 }
 253
 254 static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 255 {
 256         const struct xfrm_policy_afinfo *afinfo;
 257
 258         if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 259                 return NULL;
 260         rcu_read_lock();
 261         afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 262         if (unlikely(!afinfo))
 263                 rcu_read_unlock();
 264         return afinfo;
 265 }
 266
 267 /* Called with rcu_read_lock(). */
 268 static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 269 {
 270         return rcu_dereference(xfrm_if_cb);
 271 }
 272
 273 struct dst_entry *__xfrm_dst_lookup(int family,
 274                                     const struct xfrm_dst_lookup_params *params)
 275 {
 276         const struct xfrm_policy_afinfo *afinfo;
 277         struct dst_entry *dst;
 278
 279         afinfo = xfrm_policy_get_afinfo(family);
 280         if (unlikely(afinfo == NULL))
 281                 return ERR_PTR(-EAFNOSUPPORT);
 282
 283         dst = afinfo->dst_lookup(params);
 284
 285         rcu_read_unlock();
 286
 287         return dst;
 288 }
 289 EXPORT_SYMBOL(__xfrm_dst_lookup);
 290
 291 static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 292                                                 dscp_t dscp, int oif,
 293                                                 xfrm_address_t *prev_saddr,
 294                                                 xfrm_address_t *prev_daddr,
 295                                                 int family, u32 mark)
 296 {
 297         struct xfrm_dst_lookup_params params;
 298         struct net *net = xs_net(x);
 299         xfrm_address_t *saddr = &x->props.saddr;
 300         xfrm_address_t *daddr = &x->id.daddr;
 301         struct dst_entry *dst;
 302
 303         if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 304                 saddr = x->coaddr;
 305                 daddr = prev_daddr;
 306         }
 307         if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 308                 saddr = prev_saddr;
 309                 daddr = x->coaddr;
 310         }
 311
 312         params.net = net;
 313         params.saddr = saddr;
 314         params.daddr = daddr;
 315         params.dscp = dscp;
 316         params.oif = oif;
 317         params.mark = mark;
 318         params.ipproto = x->id.proto;
 319         if (x->encap) {
 320                 switch (x->encap->encap_type) {
 321                 case UDP_ENCAP_ESPINUDP:
 322                         params.ipproto = IPPROTO_UDP;
 323                         params.uli.ports.sport = x->encap->encap_sport;
 324                         params.uli.ports.dport = x->encap->encap_dport;
 325                         break;
 326                 case TCP_ENCAP_ESPINTCP:
 327                         params.ipproto = IPPROTO_TCP;
 328                         params.uli.ports.sport = x->encap->encap_sport;
 329                         params.uli.ports.dport = x->encap->encap_dport;
 330                         break;
 331                 }
 332         }
 333
 334         dst = __xfrm_dst_lookup(family, &params);
 335
 336         if (!IS_ERR(dst)) {
 337                 if (prev_saddr != saddr)
 338                         memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 339                 if (prev_daddr != daddr)
 340                         memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 341         }
 342
 343         return dst;
 344 }
 345
 346 static inline unsigned long make_jiffies(long secs)
 347 {
 348         if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 349                 return MAX_SCHEDULE_TIMEOUT-1;
 350         else
 351                 return secs*HZ;
 352 }
 353
 354 static void xfrm_policy_timer(struct timer_list *t)
 355 {
 356         struct xfrm_policy *xp = timer_container_of(xp, t, timer);
 357         time64_t now = ktime_get_real_seconds();
 358         time64_t next = TIME64_MAX;
 359         int warn = 0;
 360         int dir;
 361
 362         read_lock(&xp->lock);
 363
 364         if (unlikely(xp->walk.dead))
 365                 goto out;
 366
 367         dir = xfrm_policy_id2dir(xp->index);
 368
 369         if (xp->lft.hard_add_expires_seconds) {
 370                 time64_t tmo = xp->lft.hard_add_expires_seconds +
 371                         xp->curlft.add_time - now;
 372                 if (tmo <= 0)
 373                         goto expired;
 374                 if (tmo < next)
 375                         next = tmo;
 376         }
 377         if (xp->lft.hard_use_expires_seconds) {
 378                 time64_t tmo = xp->lft.hard_use_expires_seconds +
 379                         (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 380                 if (tmo <= 0)
 381                         goto expired;
 382                 if (tmo < next)
 383                         next = tmo;
 384         }
 385         if (xp->lft.soft_add_expires_seconds) {
 386                 time64_t tmo = xp->lft.soft_add_expires_seconds +
 387                         xp->curlft.add_time - now;
 388                 if (tmo <= 0) {
 389                         warn = 1;
 390                         tmo = XFRM_KM_TIMEOUT;
 391                 }
 392                 if (tmo < next)
 393                         next = tmo;
 394         }
 395         if (xp->lft.soft_use_expires_seconds) {
 396                 time64_t tmo = xp->lft.soft_use_expires_seconds +
 397                         (READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 398                 if (tmo <= 0) {
 399                         warn = 1;
 400                         tmo = XFRM_KM_TIMEOUT;
 401                 }
 402                 if (tmo < next)
 403                         next = tmo;
 404         }
 405
 406         if (warn)
 407                 km_policy_expired(xp, dir, 0, 0);
 408         if (next != TIME64_MAX &&
 409             !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 410                 xfrm_pol_hold(xp);
 411
 412 out:
 413         read_unlock(&xp->lock);
 414         xfrm_pol_put(xp);
 415         return;
 416
 417 expired:
 418         read_unlock(&xp->lock);
 419         if (!xfrm_policy_delete(xp, dir))
 420                 km_policy_expired(xp, dir, 1, 0);
 421         xfrm_pol_put(xp);
 422 }
 423
 424 /* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 425  * SPD calls.
 426  */
 427
 428 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 429 {
 430         struct xfrm_policy *policy;
 431
 432         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 433
 434         if (policy) {
 435                 write_pnet(&policy->xp_net, net);
 436                 INIT_LIST_HEAD(&policy->walk.all);
 437                 INIT_HLIST_HEAD(&policy->state_cache_list);
 438                 INIT_HLIST_NODE(&policy->bydst);
 439                 INIT_HLIST_NODE(&policy->byidx);
 440                 rwlock_init(&policy->lock);
 441                 refcount_set(&policy->refcnt, 1);
 442                 skb_queue_head_init(&policy->polq.hold_queue);
 443                 timer_setup(&policy->timer, xfrm_policy_timer, 0);
 444                 timer_setup(&policy->polq.hold_timer,
 445                             xfrm_policy_queue_process, 0);
 446         }
 447         return policy;
 448 }
 449 EXPORT_SYMBOL(xfrm_policy_alloc);
 450
 451 static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 452 {
 453         struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 454
 455         security_xfrm_policy_free(policy->security);
 456         kfree(policy);
 457 }
 458
 459 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 460
 461 void xfrm_policy_destroy(struct xfrm_policy *policy)
 462 {
 463         BUG_ON(!policy->walk.dead);
 464
 465         if (timer_delete(&policy->timer) || timer_delete(&policy->polq.hold_timer))
 466                 BUG();
 467
 468         xfrm_dev_policy_free(policy);
 469         call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 470 }
 471 EXPORT_SYMBOL(xfrm_policy_destroy);
 472
 473 /* Rule must be locked. Release descendant resources, announce
 474  * entry dead. The rule must be unlinked from lists to the moment.
 475  */
 476
 477 static void xfrm_policy_kill(struct xfrm_policy *policy)
 478 {
 479         struct net *net = xp_net(policy);
 480         struct xfrm_state *x;
 481
 482         xfrm_dev_policy_delete(policy);
 483
 484         write_lock_bh(&policy->lock);
 485         policy->walk.dead = 1;
 486         write_unlock_bh(&policy->lock);
 487
 488         atomic_inc(&policy->genid);
 489
 490         if (timer_delete(&policy->polq.hold_timer))
 491                 xfrm_pol_put(policy);
 492         skb_queue_purge(&policy->polq.hold_queue);
 493
 494         if (timer_delete(&policy->timer))
 495                 xfrm_pol_put(policy);
 496
 497         /* XXX: Flush state cache */
 498         spin_lock_bh(&net->xfrm.xfrm_state_lock);
 499         hlist_for_each_entry_rcu(x, &policy->state_cache_list, state_cache) {
 500                 hlist_del_init_rcu(&x->state_cache);
 501         }
 502         spin_unlock_bh(&net->xfrm.xfrm_state_lock);
 503
 504         xfrm_pol_put(policy);
 505 }
 506
 507 static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 508
 509 static inline unsigned int idx_hash(struct net *net, u32 index)
 510 {
 511         return __idx_hash(index, net->xfrm.policy_idx_hmask);
 512 }
 513
 514 /* calculate policy hash thresholds */
 515 static void __get_hash_thresh(struct net *net,
 516                               unsigned short family, int dir,
 517                               u8 *dbits, u8 *sbits)
 518 {
 519         switch (family) {
 520         case AF_INET:
 521                 *dbits = net->xfrm.policy_bydst[dir].dbits4;
 522                 *sbits = net->xfrm.policy_bydst[dir].sbits4;
 523                 break;
 524
 525         case AF_INET6:
 526                 *dbits = net->xfrm.policy_bydst[dir].dbits6;
 527                 *sbits = net->xfrm.policy_bydst[dir].sbits6;
 528                 break;
 529
 530         default:
 531                 *dbits = 0;
 532                 *sbits = 0;
 533         }
 534 }
 535
 536 static struct hlist_head *policy_hash_bysel(struct net *net,
 537                                             const struct xfrm_selector *sel,
 538                                             unsigned short family, int dir)
 539 {
 540         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 541         unsigned int hash;
 542         u8 dbits;
 543         u8 sbits;
 544
 545         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 546         hash = __sel_hash(sel, family, hmask, dbits, sbits);
 547
 548         if (hash == hmask + 1)
 549                 return NULL;
 550
 551         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 552                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 553 }
 554
 555 static struct hlist_head *policy_hash_direct(struct net *net,
 556                                              const xfrm_address_t *daddr,
 557                                              const xfrm_address_t *saddr,
 558                                              unsigned short family, int dir)
 559 {
 560         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 561         unsigned int hash;
 562         u8 dbits;
 563         u8 sbits;
 564
 565         __get_hash_thresh(net, family, dir, &dbits, &sbits);
 566         hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 567
 568         return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 569                      lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 570 }
 571
 572 static void xfrm_dst_hash_transfer(struct net *net,
 573                                    struct hlist_head *list,
 574                                    struct hlist_head *ndsttable,
 575                                    unsigned int nhashmask,
 576                                    int dir)
 577 {
 578         struct hlist_node *tmp, *entry0 = NULL;
 579         struct xfrm_policy *pol;
 580         unsigned int h0 = 0;
 581         u8 dbits;
 582         u8 sbits;
 583
 584 redo:
 585         hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 586                 unsigned int h;
 587
 588                 __get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 589                 h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 590                                 pol->family, nhashmask, dbits, sbits);
 591                 if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) {
 592                         hlist_del_rcu(&pol->bydst);
 593                         hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 594                         h0 = h;
 595                 } else {
 596                         if (h != h0)
 597                                 continue;
 598                         hlist_del_rcu(&pol->bydst);
 599                         hlist_add_behind_rcu(&pol->bydst, entry0);
 600                 }
 601                 entry0 = &pol->bydst;
 602         }
 603         if (!hlist_empty(list)) {
 604                 entry0 = NULL;
 605                 goto redo;
 606         }
 607 }
 608
 609 static void xfrm_idx_hash_transfer(struct hlist_head *list,
 610                                    struct hlist_head *nidxtable,
 611                                    unsigned int nhashmask)
 612 {
 613         struct hlist_node *tmp;
 614         struct xfrm_policy *pol;
 615
 616         hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 617                 unsigned int h;
 618
 619                 h = __idx_hash(pol->index, nhashmask);
 620                 hlist_add_head(&pol->byidx, nidxtable+h);
 621         }
 622 }
 623
 624 static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 625 {
 626         return ((old_hmask + 1) << 1) - 1;
 627 }
 628
 629 static void xfrm_bydst_resize(struct net *net, int dir)
 630 {
 631         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 632         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 633         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 634         struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 635         struct hlist_head *odst;
 636         int i;
 637
 638         if (!ndst)
 639                 return;
 640
 641         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 642         write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
 643
 644         odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 645                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 646
 647         for (i = hmask; i >= 0; i--)
 648                 xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 649
 650         rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 651         net->xfrm.policy_bydst[dir].hmask = nhashmask;
 652
 653         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
 654         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 655
 656         synchronize_rcu();
 657
 658         xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 659 }
 660
 661 static void xfrm_byidx_resize(struct net *net)
 662 {
 663         unsigned int hmask = net->xfrm.policy_idx_hmask;
 664         unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 665         unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 666         struct hlist_head *oidx = net->xfrm.policy_byidx;
 667         struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 668         int i;
 669
 670         if (!nidx)
 671                 return;
 672
 673         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 674
 675         for (i = hmask; i >= 0; i--)
 676                 xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 677
 678         net->xfrm.policy_byidx = nidx;
 679         net->xfrm.policy_idx_hmask = nhashmask;
 680
 681         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 682
 683         xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 684 }
 685
 686 static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 687 {
 688         unsigned int cnt = net->xfrm.policy_count[dir];
 689         unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 690
 691         if (total)
 692                 *total += cnt;
 693
 694         if ((hmask + 1) < xfrm_policy_hashmax &&
 695             cnt > hmask)
 696                 return 1;
 697
 698         return 0;
 699 }
 700
 701 static inline int xfrm_byidx_should_resize(struct net *net, int total)
 702 {
 703         unsigned int hmask = net->xfrm.policy_idx_hmask;
 704
 705         if ((hmask + 1) < xfrm_policy_hashmax &&
 706             total > hmask)
 707                 return 1;
 708
 709         return 0;
 710 }
 711
 712 void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 713 {
 714         si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 715         si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 716         si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 717         si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 718         si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 719         si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 720         si->spdhcnt = net->xfrm.policy_idx_hmask;
 721         si->spdhmcnt = xfrm_policy_hashmax;
 722 }
 723 EXPORT_SYMBOL(xfrm_spd_getinfo);
 724
 725 static DEFINE_MUTEX(hash_resize_mutex);
 726 static void xfrm_hash_resize(struct work_struct *work)
 727 {
 728         struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 729         int dir, total;
 730
 731         mutex_lock(&hash_resize_mutex);
 732
 733         total = 0;
 734         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 735                 if (xfrm_bydst_should_resize(net, dir, &total))
 736                         xfrm_bydst_resize(net, dir);
 737         }
 738         if (xfrm_byidx_should_resize(net, total))
 739                 xfrm_byidx_resize(net);
 740
 741         mutex_unlock(&hash_resize_mutex);
 742 }
 743
 744 /* Make sure *pol can be inserted into fastbin.
 745  * Useful to check that later insert requests will be successful
 746  * (provided xfrm_policy_lock is held throughout).
 747  */
 748 static struct xfrm_pol_inexact_bin *
 749 xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
 750 {
 751         struct xfrm_pol_inexact_bin *bin, *prev;
 752         struct xfrm_pol_inexact_key k = {
 753                 .family = pol->family,
 754                 .type = pol->type,
 755                 .dir = dir,
 756                 .if_id = pol->if_id,
 757         };
 758         struct net *net = xp_net(pol);
 759
 760         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
 761
 762         write_pnet(&k.net, net);
 763         bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
 764                                      xfrm_pol_inexact_params);
 765         if (bin)
 766                 return bin;
 767
 768         bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
 769         if (!bin)
 770                 return NULL;
 771
 772         bin->k = k;
 773         INIT_HLIST_HEAD(&bin->hhead);
 774         bin->root_d = RB_ROOT;
 775         bin->root_s = RB_ROOT;
 776         seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
 777
 778         prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
 779                                                 &bin->k, &bin->head,
 780                                                 xfrm_pol_inexact_params);
 781         if (!prev) {
 782                 list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
 783                 return bin;
 784         }
 785
 786         kfree(bin);
 787
 788         return IS_ERR(prev) ? NULL : prev;
 789 }
 790
 791 static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
 792                                                int family, u8 prefixlen)
 793 {
 794         if (xfrm_addr_any(addr, family))
 795                 return true;
 796
 797         if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
 798                 return true;
 799
 800         if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
 801                 return true;
 802
 803         return false;
 804 }
 805
 806 static bool
 807 xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
 808 {
 809         const xfrm_address_t *addr;
 810         bool saddr_any, daddr_any;
 811         u8 prefixlen;
 812
 813         addr = &policy->selector.saddr;
 814         prefixlen = policy->selector.prefixlen_s;
 815
 816         saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 817                                                        policy->family,
 818                                                        prefixlen);
 819         addr = &policy->selector.daddr;
 820         prefixlen = policy->selector.prefixlen_d;
 821         daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 822                                                        policy->family,
 823                                                        prefixlen);
 824         return saddr_any && daddr_any;
 825 }
 826
 827 static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
 828                                        const xfrm_address_t *addr, u8 prefixlen)
 829 {
 830         node->addr = *addr;
 831         node->prefixlen = prefixlen;
 832 }
 833
 834 static struct xfrm_pol_inexact_node *
 835 xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
 836 {
 837         struct xfrm_pol_inexact_node *node;
 838
 839         node = kzalloc(sizeof(*node), GFP_ATOMIC);
 840         if (node)
 841                 xfrm_pol_inexact_node_init(node, addr, prefixlen);
 842
 843         return node;
 844 }
 845
 846 static int xfrm_policy_addr_delta(const xfrm_address_t *a,
 847                                   const xfrm_address_t *b,
 848                                   u8 prefixlen, u16 family)
 849 {
 850         u32 ma, mb, mask;
 851         unsigned int pdw, pbi;
 852         int delta = 0;
 853
 854         switch (family) {
 855         case AF_INET:
 856                 if (prefixlen == 0)
 857                         return 0;
 858                 mask = ~0U << (32 - prefixlen);
 859                 ma = ntohl(a->a4) & mask;
 860                 mb = ntohl(b->a4) & mask;
 861                 if (ma < mb)
 862                         delta = -1;
 863                 else if (ma > mb)
 864                         delta = 1;
 865                 break;
 866         case AF_INET6:
 867                 pdw = prefixlen >> 5;
 868                 pbi = prefixlen & 0x1f;
 869
 870                 if (pdw) {
 871                         delta = memcmp(a->a6, b->a6, pdw << 2);
 872                         if (delta)
 873                                 return delta;
 874                 }
 875                 if (pbi) {
 876                         mask = ~0U << (32 - pbi);
 877                         ma = ntohl(a->a6[pdw]) & mask;
 878                         mb = ntohl(b->a6[pdw]) & mask;
 879                         if (ma < mb)
 880                                 delta = -1;
 881                         else if (ma > mb)
 882                                 delta = 1;
 883                 }
 884                 break;
 885         default:
 886                 break;
 887         }
 888
 889         return delta;
 890 }
 891
 892 static void xfrm_policy_inexact_list_reinsert(struct net *net,
 893                                               struct xfrm_pol_inexact_node *n,
 894                                               u16 family)
 895 {
 896         unsigned int matched_s, matched_d;
 897         struct xfrm_policy *policy, *p;
 898
 899         matched_s = 0;
 900         matched_d = 0;
 901
 902         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 903                 struct hlist_node *newpos = NULL;
 904                 bool matches_s, matches_d;
 905
 906                 if (policy->walk.dead || !policy->bydst_reinsert)
 907                         continue;
 908
 909                 WARN_ON_ONCE(policy->family != family);
 910
 911                 policy->bydst_reinsert = false;
 912                 hlist_for_each_entry(p, &n->hhead, bydst) {
 913                         if (policy->priority > p->priority)
 914                                 newpos = &p->bydst;
 915                         else if (policy->priority == p->priority &&
 916                                  policy->pos > p->pos)
 917                                 newpos = &p->bydst;
 918                         else
 919                                 break;
 920                 }
 921
 922                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
 923                         hlist_add_behind_rcu(&policy->bydst, newpos);
 924                 else
 925                         hlist_add_head_rcu(&policy->bydst, &n->hhead);
 926
 927                 /* paranoia checks follow.
 928                  * Check that the reinserted policy matches at least
 929                  * saddr or daddr for current node prefix.
 930                  *
 931                  * Matching both is fine, matching saddr in one policy
 932                  * (but not daddr) and then matching only daddr in another
 933                  * is a bug.
 934                  */
 935                 matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
 936                                                    &n->addr,
 937                                                    n->prefixlen,
 938                                                    family) == 0;
 939                 matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
 940                                                    &n->addr,
 941                                                    n->prefixlen,
 942                                                    family) == 0;
 943                 if (matches_s && matches_d)
 944                         continue;
 945
 946                 WARN_ON_ONCE(!matches_s && !matches_d);
 947                 if (matches_s)
 948                         matched_s++;
 949                 if (matches_d)
 950                         matched_d++;
 951                 WARN_ON_ONCE(matched_s && matched_d);
 952         }
 953 }
 954
 955 static void xfrm_policy_inexact_node_reinsert(struct net *net,
 956                                               struct xfrm_pol_inexact_node *n,
 957                                               struct rb_root *new,
 958                                               u16 family)
 959 {
 960         struct xfrm_pol_inexact_node *node;
 961         struct rb_node **p, *parent;
 962
 963         /* we should not have another subtree here */
 964         WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
 965 restart:
 966         parent = NULL;
 967         p = &new->rb_node;
 968         while (*p) {
 969                 u8 prefixlen;
 970                 int delta;
 971
 972                 parent = *p;
 973                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 974
 975                 prefixlen = min(node->prefixlen, n->prefixlen);
 976
 977                 delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
 978                                                prefixlen, family);
 979                 if (delta < 0) {
 980                         p = &parent->rb_left;
 981                 } else if (delta > 0) {
 982                         p = &parent->rb_right;
 983                 } else {
 984                         bool same_prefixlen = node->prefixlen == n->prefixlen;
 985                         struct xfrm_policy *tmp;
 986
 987                         hlist_for_each_entry(tmp, &n->hhead, bydst) {
 988                                 tmp->bydst_reinsert = true;
 989                                 hlist_del_rcu(&tmp->bydst);
 990                         }
 991
 992                         node->prefixlen = prefixlen;
 993
 994                         xfrm_policy_inexact_list_reinsert(net, node, family);
 995
 996                         if (same_prefixlen) {
 997                                 kfree_rcu(n, rcu);
 998                                 return;
 999                         }
1000
1001                         rb_erase(*p, new);
1002                         kfree_rcu(n, rcu);
1003                         n = node;
1004                         goto restart;
1005                 }
1006         }
1007
1008         rb_link_node_rcu(&n->node, parent, p);
1009         rb_insert_color(&n->node, new);
1010 }
1011
1012 /* merge nodes v and n */
1013 static void xfrm_policy_inexact_node_merge(struct net *net,
1014                                            struct xfrm_pol_inexact_node *v,
1015                                            struct xfrm_pol_inexact_node *n,
1016                                            u16 family)
1017 {
1018         struct xfrm_pol_inexact_node *node;
1019         struct xfrm_policy *tmp;
1020         struct rb_node *rnode;
1021
1022         /* To-be-merged node v has a subtree.
1023          *
1024          * Dismantle it and insert its nodes to n->root.
1025          */
1026         while ((rnode = rb_first(&v->root)) != NULL) {
1027                 node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
1028                 rb_erase(&node->node, &v->root);
1029                 xfrm_policy_inexact_node_reinsert(net, node, &n->root,
1030                                                   family);
1031         }
1032
1033         hlist_for_each_entry(tmp, &v->hhead, bydst) {
1034                 tmp->bydst_reinsert = true;
1035                 hlist_del_rcu(&tmp->bydst);
1036         }
1037
1038         xfrm_policy_inexact_list_reinsert(net, n, family);
1039 }
1040
1041 static struct xfrm_pol_inexact_node *
1042 xfrm_policy_inexact_insert_node(struct net *net,
1043                                 struct rb_root *root,
1044                                 xfrm_address_t *addr,
1045                                 u16 family, u8 prefixlen, u8 dir)
1046 {
1047         struct xfrm_pol_inexact_node *cached = NULL;
1048         struct rb_node **p, *parent = NULL;
1049         struct xfrm_pol_inexact_node *node;
1050
1051         p = &root->rb_node;
1052         while (*p) {
1053                 int delta;
1054
1055                 parent = *p;
1056                 node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
1057
1058                 delta = xfrm_policy_addr_delta(addr, &node->addr,
1059                                                node->prefixlen,
1060                                                family);
1061                 if (delta == 0 && prefixlen >= node->prefixlen) {
1062                         WARN_ON_ONCE(cached); /* ipsec policies got lost */
1063                         return node;
1064                 }
1065
1066                 if (delta < 0)
1067                         p = &parent->rb_left;
1068                 else
1069                         p = &parent->rb_right;
1070
1071                 if (prefixlen < node->prefixlen) {
1072                         delta = xfrm_policy_addr_delta(addr, &node->addr,
1073                                                        prefixlen,
1074                                                        family);
1075                         if (delta)
1076                                 continue;
1077
1078                         /* This node is a subnet of the new prefix. It needs
1079                          * to be removed and re-inserted with the smaller
1080                          * prefix and all nodes that are now also covered
1081                          * by the reduced prefixlen.
1082                          */
1083                         rb_erase(&node->node, root);
1084
1085                         if (!cached) {
1086                                 xfrm_pol_inexact_node_init(node, addr,
1087                                                            prefixlen);
1088                                 cached = node;
1089                         } else {
1090                                 /* This node also falls within the new
1091                                  * prefixlen. Merge the to-be-reinserted
1092                                  * node and this one.
1093                                  */
1094                                 xfrm_policy_inexact_node_merge(net, node,
1095                                                                cached, family);
1096                                 kfree_rcu(node, rcu);
1097                         }
1098
1099                         /* restart */
1100                         p = &root->rb_node;
1101                         parent = NULL;
1102                 }
1103         }
1104
1105         node = cached;
1106         if (!node) {
1107                 node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1108                 if (!node)
1109                         return NULL;
1110         }
1111
1112         rb_link_node_rcu(&node->node, parent, p);
1113         rb_insert_color(&node->node, root);
1114
1115         return node;
1116 }
1117
1118 static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1119 {
1120         struct xfrm_pol_inexact_node *node;
1121         struct rb_node *rn = rb_first(r);
1122
1123         while (rn) {
1124                 node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1125
1126                 xfrm_policy_inexact_gc_tree(&node->root, rm);
1127                 rn = rb_next(rn);
1128
1129                 if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1130                         WARN_ON_ONCE(rm);
1131                         continue;
1132                 }
1133
1134                 rb_erase(&node->node, r);
1135                 kfree_rcu(node, rcu);
1136         }
1137 }
1138
1139 static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1140 {
1141         write_seqcount_begin(&b->count);
1142         xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1143         xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1144         write_seqcount_end(&b->count);
1145
1146         if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1147             !hlist_empty(&b->hhead)) {
1148                 WARN_ON_ONCE(net_exit);
1149                 return;
1150         }
1151
1152         if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1153                                    xfrm_pol_inexact_params) == 0) {
1154                 list_del(&b->inexact_bins);
1155                 kfree_rcu(b, rcu);
1156         }
1157 }
1158
1159 static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1160 {
1161         struct net *net = read_pnet(&b->k.net);
1162
1163         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1164         __xfrm_policy_inexact_prune_bin(b, false);
1165         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1166 }
1167
1168 static void __xfrm_policy_inexact_flush(struct net *net)
1169 {
1170         struct xfrm_pol_inexact_bin *bin, *t;
1171
1172         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1173
1174         list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1175                 __xfrm_policy_inexact_prune_bin(bin, false);
1176 }
1177
1178 static struct hlist_head *
1179 xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1180                                 struct xfrm_policy *policy, u8 dir)
1181 {
1182         struct xfrm_pol_inexact_node *n;
1183         struct net *net;
1184
1185         net = xp_net(policy);
1186         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1187
1188         if (xfrm_policy_inexact_insert_use_any_list(policy))
1189                 return &bin->hhead;
1190
1191         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1192                                                policy->family,
1193                                                policy->selector.prefixlen_d)) {
1194                 write_seqcount_begin(&bin->count);
1195                 n = xfrm_policy_inexact_insert_node(net,
1196                                                     &bin->root_s,
1197                                                     &policy->selector.saddr,
1198                                                     policy->family,
1199                                                     policy->selector.prefixlen_s,
1200                                                     dir);
1201                 write_seqcount_end(&bin->count);
1202                 if (!n)
1203                         return NULL;
1204
1205                 return &n->hhead;
1206         }
1207
1208         /* daddr is fixed */
1209         write_seqcount_begin(&bin->count);
1210         n = xfrm_policy_inexact_insert_node(net,
1211                                             &bin->root_d,
1212                                             &policy->selector.daddr,
1213                                             policy->family,
1214                                             policy->selector.prefixlen_d, dir);
1215         write_seqcount_end(&bin->count);
1216         if (!n)
1217                 return NULL;
1218
1219         /* saddr is wildcard */
1220         if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1221                                                policy->family,
1222                                                policy->selector.prefixlen_s))
1223                 return &n->hhead;
1224
1225         write_seqcount_begin(&bin->count);
1226         n = xfrm_policy_inexact_insert_node(net,
1227                                             &n->root,
1228                                             &policy->selector.saddr,
1229                                             policy->family,
1230                                             policy->selector.prefixlen_s, dir);
1231         write_seqcount_end(&bin->count);
1232         if (!n)
1233                 return NULL;
1234
1235         return &n->hhead;
1236 }
1237
1238 static struct xfrm_policy *
1239 xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1240 {
1241         struct xfrm_pol_inexact_bin *bin;
1242         struct xfrm_policy *delpol;
1243         struct hlist_head *chain;
1244         struct net *net;
1245
1246         bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1247         if (!bin)
1248                 return ERR_PTR(-ENOMEM);
1249
1250         net = xp_net(policy);
1251         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1252
1253         chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1254         if (!chain) {
1255                 __xfrm_policy_inexact_prune_bin(bin, false);
1256                 return ERR_PTR(-ENOMEM);
1257         }
1258
1259         delpol = xfrm_policy_insert_list(chain, policy, excl);
1260         if (delpol && excl) {
1261                 __xfrm_policy_inexact_prune_bin(bin, false);
1262                 return ERR_PTR(-EEXIST);
1263         }
1264
1265         if (delpol)
1266                 __xfrm_policy_inexact_prune_bin(bin, false);
1267
1268         return delpol;
1269 }
1270
1271 static bool xfrm_policy_is_dead_or_sk(const struct xfrm_policy *policy)
1272 {
1273         int dir;
1274
1275         if (policy->walk.dead)
1276                 return true;
1277
1278         dir = xfrm_policy_id2dir(policy->index);
1279         return dir >= XFRM_POLICY_MAX;
1280 }
1281
1282 static void xfrm_hash_rebuild(struct work_struct *work)
1283 {
1284         struct net *net = container_of(work, struct net,
1285                                        xfrm.policy_hthresh.work);
1286         struct xfrm_policy *pol;
1287         struct xfrm_policy *policy;
1288         struct hlist_head *chain;
1289         struct hlist_node *newpos;
1290         int dir;
1291         unsigned seq;
1292         u8 lbits4, rbits4, lbits6, rbits6;
1293
1294         mutex_lock(&hash_resize_mutex);
1295
1296         /* read selector prefixlen thresholds */
1297         do {
1298                 seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1299
1300                 lbits4 = net->xfrm.policy_hthresh.lbits4;
1301                 rbits4 = net->xfrm.policy_hthresh.rbits4;
1302                 lbits6 = net->xfrm.policy_hthresh.lbits6;
1303                 rbits6 = net->xfrm.policy_hthresh.rbits6;
1304         } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1305
1306         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1307         write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
1308
1309         /* make sure that we can insert the indirect policies again before
1310          * we start with destructive action.
1311          */
1312         list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1313                 struct xfrm_pol_inexact_bin *bin;
1314                 u8 dbits, sbits;
1315
1316                 if (xfrm_policy_is_dead_or_sk(policy))
1317                         continue;
1318
1319                 dir = xfrm_policy_id2dir(policy->index);
1320                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1321                         if (policy->family == AF_INET) {
1322                                 dbits = rbits4;
1323                                 sbits = lbits4;
1324                         } else {
1325                                 dbits = rbits6;
1326                                 sbits = lbits6;
1327                         }
1328                 } else {
1329                         if (policy->family == AF_INET) {
1330                                 dbits = lbits4;
1331                                 sbits = rbits4;
1332                         } else {
1333                                 dbits = lbits6;
1334                                 sbits = rbits6;
1335                         }
1336                 }
1337
1338                 if (policy->selector.prefixlen_d < dbits ||
1339                     policy->selector.prefixlen_s < sbits)
1340                         continue;
1341
1342                 bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1343                 if (!bin)
1344                         goto out_unlock;
1345
1346                 if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1347                         goto out_unlock;
1348         }
1349
1350         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1351                 if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1352                         /* dir out => dst = remote, src = local */
1353                         net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1354                         net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1355                         net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1356                         net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1357                 } else {
1358                         /* dir in/fwd => dst = local, src = remote */
1359                         net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1360                         net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1361                         net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1362                         net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1363                 }
1364         }
1365
1366         /* re-insert all policies by order of creation */
1367         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1368                 if (xfrm_policy_is_dead_or_sk(policy))
1369                         continue;
1370
1371                 hlist_del_rcu(&policy->bydst);
1372
1373                 newpos = NULL;
1374                 dir = xfrm_policy_id2dir(policy->index);
1375                 chain = policy_hash_bysel(net, &policy->selector,
1376                                           policy->family, dir);
1377
1378                 if (!chain) {
1379                         void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1380
1381                         WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1382                         continue;
1383                 }
1384
1385                 hlist_for_each_entry(pol, chain, bydst) {
1386                         if (policy->priority >= pol->priority)
1387                                 newpos = &pol->bydst;
1388                         else
1389                                 break;
1390                 }
1391                 if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1392                         hlist_add_behind_rcu(&policy->bydst, newpos);
1393                 else
1394                         hlist_add_head_rcu(&policy->bydst, chain);
1395         }
1396
1397 out_unlock:
1398         __xfrm_policy_inexact_flush(net);
1399         write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1400         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1401
1402         mutex_unlock(&hash_resize_mutex);
1403 }
1404
1405 void xfrm_policy_hash_rebuild(struct net *net)
1406 {
1407         schedule_work(&net->xfrm.policy_hthresh.work);
1408 }
1409 EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1410
1411 /* Generate new index... KAME seems to generate them ordered by cost
1412  * of an absolute inpredictability of ordering of rules. This will not pass. */
1413 static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1414 {
1415         for (;;) {
1416                 struct hlist_head *list;
1417                 struct xfrm_policy *p;
1418                 u32 idx;
1419                 int found;
1420
1421                 if (!index) {
1422                         idx = (net->xfrm.idx_generator | dir);
1423                         net->xfrm.idx_generator += 8;
1424                 } else {
1425                         idx = index;
1426                         index = 0;
1427                 }
1428
1429                 if (idx == 0)
1430                         idx = 8;
1431                 list = net->xfrm.policy_byidx + idx_hash(net, idx);
1432                 found = 0;
1433                 hlist_for_each_entry(p, list, byidx) {
1434                         if (p->index == idx) {
1435                                 found = 1;
1436                                 break;
1437                         }
1438                 }
1439                 if (!found)
1440                         return idx;
1441         }
1442 }
1443
1444 static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1445 {
1446         u32 *p1 = (u32 *) s1;
1447         u32 *p2 = (u32 *) s2;
1448         int len = sizeof(struct xfrm_selector) / sizeof(u32);
1449         int i;
1450
1451         for (i = 0; i < len; i++) {
1452                 if (p1[i] != p2[i])
1453                         return 1;
1454         }
1455
1456         return 0;
1457 }
1458
1459 static void xfrm_policy_requeue(struct xfrm_policy *old,
1460                                 struct xfrm_policy *new)
1461 {
1462         struct xfrm_policy_queue *pq = &old->polq;
1463         struct sk_buff_head list;
1464
1465         if (skb_queue_empty(&pq->hold_queue))
1466                 return;
1467
1468         __skb_queue_head_init(&list);
1469
1470         spin_lock_bh(&pq->hold_queue.lock);
1471         skb_queue_splice_init(&pq->hold_queue, &list);
1472         if (timer_delete(&pq->hold_timer))
1473                 xfrm_pol_put(old);
1474         spin_unlock_bh(&pq->hold_queue.lock);
1475
1476         pq = &new->polq;
1477
1478         spin_lock_bh(&pq->hold_queue.lock);
1479         skb_queue_splice(&list, &pq->hold_queue);
1480         pq->timeout = XFRM_QUEUE_TMO_MIN;
1481         if (!mod_timer(&pq->hold_timer, jiffies))
1482                 xfrm_pol_hold(new);
1483         spin_unlock_bh(&pq->hold_queue.lock);
1484 }
1485
1486 static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1487                                           struct xfrm_policy *pol)
1488 {
1489         return mark->v == pol->mark.v && mark->m == pol->mark.m;
1490 }
1491
1492 static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1493 {
1494         const struct xfrm_pol_inexact_key *k = data;
1495         u32 a = k->type << 24 | k->dir << 16 | k->family;
1496
1497         return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1498                             seed);
1499 }
1500
1501 static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1502 {
1503         const struct xfrm_pol_inexact_bin *b = data;
1504
1505         return xfrm_pol_bin_key(&b->k, 0, seed);
1506 }
1507
1508 static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1509                             const void *ptr)
1510 {
1511         const struct xfrm_pol_inexact_key *key = arg->key;
1512         const struct xfrm_pol_inexact_bin *b = ptr;
1513         int ret;
1514
1515         if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1516                 return -1;
1517
1518         ret = b->k.dir ^ key->dir;
1519         if (ret)
1520                 return ret;
1521
1522         ret = b->k.type ^ key->type;
1523         if (ret)
1524                 return ret;
1525
1526         ret = b->k.family ^ key->family;
1527         if (ret)
1528                 return ret;
1529
1530         return b->k.if_id ^ key->if_id;
1531 }
1532
1533 static const struct rhashtable_params xfrm_pol_inexact_params = {
1534         .head_offset            = offsetof(struct xfrm_pol_inexact_bin, head),
1535         .hashfn                 = xfrm_pol_bin_key,
1536         .obj_hashfn             = xfrm_pol_bin_obj,
1537         .obj_cmpfn              = xfrm_pol_bin_cmp,
1538         .automatic_shrinking    = true,
1539 };
1540
1541 static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1542                                                    struct xfrm_policy *policy,
1543                                                    bool excl)
1544 {
1545         struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1546
1547         hlist_for_each_entry(pol, chain, bydst) {
1548                 if (pol->type == policy->type &&
1549                     pol->if_id == policy->if_id &&
1550                     !selector_cmp(&pol->selector, &policy->selector) &&
1551                     xfrm_policy_mark_match(&policy->mark, pol) &&
1552                     xfrm_sec_ctx_match(pol->security, policy->security) &&
1553                     !WARN_ON(delpol)) {
1554                         if (excl)
1555                                 return ERR_PTR(-EEXIST);
1556                         delpol = pol;
1557                         if (policy->priority > pol->priority)
1558                                 continue;
1559                 } else if (policy->priority >= pol->priority) {
1560                         newpos = pol;
1561                         continue;
1562                 }
1563                 if (delpol)
1564                         break;
1565         }
1566
1567         if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1568                 hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1569         else
1570                 /* Packet offload policies enter to the head
1571                  * to speed-up lookups.
1572                  */
1573                 hlist_add_head_rcu(&policy->bydst, chain);
1574
1575         return delpol;
1576 }
1577
1578 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1579 {
1580         struct net *net = xp_net(policy);
1581         struct xfrm_policy *delpol;
1582         struct hlist_head *chain;
1583
1584         /* Sanitize mark before store */
1585         policy->mark.v &= policy->mark.m;
1586
1587         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1588         chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1589         if (chain)
1590                 delpol = xfrm_policy_insert_list(chain, policy, excl);
1591         else
1592                 delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1593
1594         if (IS_ERR(delpol)) {
1595                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1596                 return PTR_ERR(delpol);
1597         }
1598
1599         __xfrm_policy_link(policy, dir);
1600
1601         /* After previous checking, family can either be AF_INET or AF_INET6 */
1602         if (policy->family == AF_INET)
1603                 rt_genid_bump_ipv4(net);
1604         else
1605                 rt_genid_bump_ipv6(net);
1606
1607         if (delpol) {
1608                 xfrm_policy_requeue(delpol, policy);
1609                 __xfrm_policy_unlink(delpol, dir);
1610         }
1611         policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1612         hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1613         policy->curlft.add_time = ktime_get_real_seconds();
1614         policy->curlft.use_time = 0;
1615         if (!mod_timer(&policy->timer, jiffies + HZ))
1616                 xfrm_pol_hold(policy);
1617         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1618
1619         if (delpol)
1620                 xfrm_policy_kill(delpol);
1621         else if (xfrm_bydst_should_resize(net, dir, NULL))
1622                 schedule_work(&net->xfrm.policy_hash_work);
1623
1624         return 0;
1625 }
1626 EXPORT_SYMBOL(xfrm_policy_insert);
1627
1628 static struct xfrm_policy *
1629 __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1630                         u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
1631                         struct xfrm_sec_ctx *ctx)
1632 {
1633         struct xfrm_policy *pol;
1634
1635         if (!chain)
1636                 return NULL;
1637
1638         hlist_for_each_entry(pol, chain, bydst) {
1639                 if (pol->type == type &&
1640                     pol->if_id == if_id &&
1641                     xfrm_policy_mark_match(mark, pol) &&
1642                     !selector_cmp(sel, &pol->selector) &&
1643                     xfrm_sec_ctx_match(ctx, pol->security))
1644                         return pol;
1645         }
1646
1647         return NULL;
1648 }
1649
1650 struct xfrm_policy *
1651 xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1652                       u8 type, int dir, struct xfrm_selector *sel,
1653                       struct xfrm_sec_ctx *ctx, int delete, int *err)
1654 {
1655         struct xfrm_pol_inexact_bin *bin = NULL;
1656         struct xfrm_policy *pol, *ret = NULL;
1657         struct hlist_head *chain;
1658
1659         *err = 0;
1660         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1661         chain = policy_hash_bysel(net, sel, sel->family, dir);
1662         if (!chain) {
1663                 struct xfrm_pol_inexact_candidates cand;
1664                 int i;
1665
1666                 bin = xfrm_policy_inexact_lookup(net, type,
1667                                                  sel->family, dir, if_id);
1668                 if (!bin) {
1669                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1670                         return NULL;
1671                 }
1672
1673                 if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1674                                                          &sel->saddr,
1675                                                          &sel->daddr)) {
1676                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1677                         return NULL;
1678                 }
1679
1680                 pol = NULL;
1681                 for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1682                         struct xfrm_policy *tmp;
1683
1684                         tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1685                                                       if_id, type, dir,
1686                                                       sel, ctx);
1687                         if (!tmp)
1688                                 continue;
1689
1690                         if (!pol || tmp->pos < pol->pos)
1691                                 pol = tmp;
1692                 }
1693         } else {
1694                 pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1695                                               sel, ctx);
1696         }
1697
1698         if (pol) {
1699                 xfrm_pol_hold(pol);
1700                 if (delete) {
1701                         *err = security_xfrm_policy_delete(pol->security);
1702                         if (*err) {
1703                                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1704                                 return pol;
1705                         }
1706                         __xfrm_policy_unlink(pol, dir);
1707                 }
1708                 ret = pol;
1709         }
1710         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1711
1712         if (ret && delete)
1713                 xfrm_policy_kill(ret);
1714         if (bin && delete)
1715                 xfrm_policy_inexact_prune_bin(bin);
1716         return ret;
1717 }
1718 EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1719
1720 struct xfrm_policy *
1721 xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1722                  u8 type, int dir, u32 id, int delete, int *err)
1723 {
1724         struct xfrm_policy *pol, *ret;
1725         struct hlist_head *chain;
1726
1727         *err = -ENOENT;
1728         if (xfrm_policy_id2dir(id) != dir)
1729                 return NULL;
1730
1731         *err = 0;
1732         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1733         chain = net->xfrm.policy_byidx + idx_hash(net, id);
1734         ret = NULL;
1735         hlist_for_each_entry(pol, chain, byidx) {
1736                 if (pol->type == type && pol->index == id &&
1737                     pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
1738                         xfrm_pol_hold(pol);
1739                         if (delete) {
1740                                 *err = security_xfrm_policy_delete(
1741                                                                 pol->security);
1742                                 if (*err) {
1743                                         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1744                                         return pol;
1745                                 }
1746                                 __xfrm_policy_unlink(pol, dir);
1747                         }
1748                         ret = pol;
1749                         break;
1750                 }
1751         }
1752         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1753
1754         if (ret && delete)
1755                 xfrm_policy_kill(ret);
1756         return ret;
1757 }
1758 EXPORT_SYMBOL(xfrm_policy_byid);
1759
1760 #ifdef CONFIG_SECURITY_NETWORK_XFRM
1761 static inline int
1762 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1763 {
1764         struct xfrm_policy *pol;
1765         int err = 0;
1766
1767         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1768                 if (pol->walk.dead ||
1769                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1770                     pol->type != type)
1771                         continue;
1772
1773                 err = security_xfrm_policy_delete(pol->security);
1774                 if (err) {
1775                         xfrm_audit_policy_delete(pol, 0, task_valid);
1776                         return err;
1777                 }
1778         }
1779         return err;
1780 }
1781
1782 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1783                                                      struct net_device *dev,
1784                                                      bool task_valid)
1785 {
1786         struct xfrm_policy *pol;
1787         int err = 0;
1788
1789         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1790                 if (pol->walk.dead ||
1791                     xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1792                     pol->xdo.dev != dev)
1793                         continue;
1794
1795                 err = security_xfrm_policy_delete(pol->security);
1796                 if (err) {
1797                         xfrm_audit_policy_delete(pol, 0, task_valid);
1798                         return err;
1799                 }
1800         }
1801         return err;
1802 }
1803 #else
1804 static inline int
1805 xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1806 {
1807         return 0;
1808 }
1809
1810 static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1811                                                      struct net_device *dev,
1812                                                      bool task_valid)
1813 {
1814         return 0;
1815 }
1816 #endif
1817
1818 int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1819 {
1820         int dir, err = 0, cnt = 0;
1821         struct xfrm_policy *pol;
1822
1823         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1824
1825         err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1826         if (err)
1827                 goto out;
1828
1829 again:
1830         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1831                 if (pol->walk.dead)
1832                         continue;
1833
1834                 dir = xfrm_policy_id2dir(pol->index);
1835                 if (dir >= XFRM_POLICY_MAX ||
1836                     pol->type != type)
1837                         continue;
1838
1839                 __xfrm_policy_unlink(pol, dir);
1840                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1841                 cnt++;
1842                 xfrm_audit_policy_delete(pol, 1, task_valid);
1843                 xfrm_policy_kill(pol);
1844                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1845                 goto again;
1846         }
1847         if (cnt)
1848                 __xfrm_policy_inexact_flush(net);
1849         else
1850                 err = -ESRCH;
1851 out:
1852         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1853         return err;
1854 }
1855 EXPORT_SYMBOL(xfrm_policy_flush);
1856
1857 int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
1858                           bool task_valid)
1859 {
1860         int dir, err = 0, cnt = 0;
1861         struct xfrm_policy *pol;
1862
1863         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1864
1865         err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
1866         if (err)
1867                 goto out;
1868
1869 again:
1870         list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1871                 if (pol->walk.dead)
1872                         continue;
1873
1874                 dir = xfrm_policy_id2dir(pol->index);
1875                 if (dir >= XFRM_POLICY_MAX ||
1876                     pol->xdo.dev != dev)
1877                         continue;
1878
1879                 __xfrm_policy_unlink(pol, dir);
1880                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1881                 cnt++;
1882                 xfrm_audit_policy_delete(pol, 1, task_valid);
1883                 xfrm_policy_kill(pol);
1884                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1885                 goto again;
1886         }
1887         if (cnt)
1888                 __xfrm_policy_inexact_flush(net);
1889         else
1890                 err = -ESRCH;
1891 out:
1892         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1893         return err;
1894 }
1895 EXPORT_SYMBOL(xfrm_dev_policy_flush);
1896
1897 int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1898                      int (*func)(struct xfrm_policy *, int, int, void*),
1899                      void *data)
1900 {
1901         struct xfrm_policy *pol;
1902         struct xfrm_policy_walk_entry *x;
1903         int error = 0;
1904
1905         if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1906             walk->type != XFRM_POLICY_TYPE_ANY)
1907                 return -EINVAL;
1908
1909         if (list_empty(&walk->walk.all) && walk->seq != 0)
1910                 return 0;
1911
1912         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1913         if (list_empty(&walk->walk.all))
1914                 x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1915         else
1916                 x = list_first_entry(&walk->walk.all,
1917                                      struct xfrm_policy_walk_entry, all);
1918
1919         list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1920                 if (x->dead)
1921                         continue;
1922                 pol = container_of(x, struct xfrm_policy, walk);
1923                 if (walk->type != XFRM_POLICY_TYPE_ANY &&
1924                     walk->type != pol->type)
1925                         continue;
1926                 error = func(pol, xfrm_policy_id2dir(pol->index),
1927                              walk->seq, data);
1928                 if (error) {
1929                         list_move_tail(&walk->walk.all, &x->all);
1930                         goto out;
1931                 }
1932                 walk->seq++;
1933         }
1934         if (walk->seq == 0) {
1935                 error = -ENOENT;
1936                 goto out;
1937         }
1938         list_del_init(&walk->walk.all);
1939 out:
1940         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1941         return error;
1942 }
1943 EXPORT_SYMBOL(xfrm_policy_walk);
1944
1945 void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1946 {
1947         INIT_LIST_HEAD(&walk->walk.all);
1948         walk->walk.dead = 1;
1949         walk->type = type;
1950         walk->seq = 0;
1951 }
1952 EXPORT_SYMBOL(xfrm_policy_walk_init);
1953
1954 void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1955 {
1956         if (list_empty(&walk->walk.all))
1957                 return;
1958
1959         spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1960         list_del(&walk->walk.all);
1961         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1962 }
1963 EXPORT_SYMBOL(xfrm_policy_walk_done);
1964
1965 /*
1966  * Find policy to apply to this flow.
1967  *
1968  * Returns 0 if policy found, else an -errno.
1969  */
1970 static int xfrm_policy_match(const struct xfrm_policy *pol,
1971                              const struct flowi *fl,
1972                              u8 type, u16 family, u32 if_id)
1973 {
1974         const struct xfrm_selector *sel = &pol->selector;
1975         int ret = -ESRCH;
1976         bool match;
1977
1978         if (pol->family != family ||
1979             pol->if_id != if_id ||
1980             (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1981             pol->type != type)
1982                 return ret;
1983
1984         match = xfrm_selector_match(sel, fl, family);
1985         if (match)
1986                 ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
1987         return ret;
1988 }
1989
1990 static struct xfrm_pol_inexact_node *
1991 xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1992                                 seqcount_spinlock_t *count,
1993                                 const xfrm_address_t *addr, u16 family)
1994 {
1995         const struct rb_node *parent;
1996         int seq;
1997
1998 again:
1999         seq = read_seqcount_begin(count);
2000
2001         parent = rcu_dereference_raw(r->rb_node);
2002         while (parent) {
2003                 struct xfrm_pol_inexact_node *node;
2004                 int delta;
2005
2006                 node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
2007
2008                 delta = xfrm_policy_addr_delta(addr, &node->addr,
2009                                                node->prefixlen, family);
2010                 if (delta < 0) {
2011                         parent = rcu_dereference_raw(parent->rb_left);
2012                         continue;
2013                 } else if (delta > 0) {
2014                         parent = rcu_dereference_raw(parent->rb_right);
2015                         continue;
2016                 }
2017
2018                 return node;
2019         }
2020
2021         if (read_seqcount_retry(count, seq))
2022                 goto again;
2023
2024         return NULL;
2025 }
2026
2027 static bool
2028 xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
2029                                     struct xfrm_pol_inexact_bin *b,
2030                                     const xfrm_address_t *saddr,
2031                                     const xfrm_address_t *daddr)
2032 {
2033         struct xfrm_pol_inexact_node *n;
2034         u16 family;
2035
2036         if (!b)
2037                 return false;
2038
2039         family = b->k.family;
2040         memset(cand, 0, sizeof(*cand));
2041         cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
2042
2043         n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
2044                                             family);
2045         if (n) {
2046                 cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
2047                 n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
2048                                                     family);
2049                 if (n)
2050                         cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
2051         }
2052
2053         n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
2054                                             family);
2055         if (n)
2056                 cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
2057
2058         return true;
2059 }
2060
2061 static struct xfrm_pol_inexact_bin *
2062 xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
2063                                u8 dir, u32 if_id)
2064 {
2065         struct xfrm_pol_inexact_key k = {
2066                 .family = family,
2067                 .type = type,
2068                 .dir = dir,
2069                 .if_id = if_id,
2070         };
2071
2072         write_pnet(&k.net, net);
2073
2074         return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
2075                                  xfrm_pol_inexact_params);
2076 }
2077
2078 static struct xfrm_pol_inexact_bin *
2079 xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2080                            u8 dir, u32 if_id)
2081 {
2082         struct xfrm_pol_inexact_bin *bin;
2083
2084         lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2085
2086         rcu_read_lock();
2087         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2088         rcu_read_unlock();
2089
2090         return bin;
2091 }
2092
2093 static struct xfrm_policy *
2094 __xfrm_policy_eval_candidates(struct hlist_head *chain,
2095                               struct xfrm_policy *prefer,
2096                               const struct flowi *fl,
2097                               u8 type, u16 family, u32 if_id)
2098 {
2099         u32 priority = prefer ? prefer->priority : ~0u;
2100         struct xfrm_policy *pol;
2101
2102         if (!chain)
2103                 return NULL;
2104
2105         hlist_for_each_entry_rcu(pol, chain, bydst) {
2106                 int err;
2107
2108                 if (pol->priority > priority)
2109                         break;
2110
2111                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2112                 if (err) {
2113                         if (err != -ESRCH)
2114                                 return ERR_PTR(err);
2115
2116                         continue;
2117                 }
2118
2119                 if (prefer) {
2120                         /* matches.  Is it older than *prefer? */
2121                         if (pol->priority == priority &&
2122                             prefer->pos < pol->pos)
2123                                 return prefer;
2124                 }
2125
2126                 return pol;
2127         }
2128
2129         return NULL;
2130 }
2131
2132 static struct xfrm_policy *
2133 xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2134                             struct xfrm_policy *prefer,
2135                             const struct flowi *fl,
2136                             u8 type, u16 family, u32 if_id)
2137 {
2138         struct xfrm_policy *tmp;
2139         int i;
2140
2141         for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2142                 tmp = __xfrm_policy_eval_candidates(cand->res[i],
2143                                                     prefer,
2144                                                     fl, type, family, if_id);
2145                 if (!tmp)
2146                         continue;
2147
2148                 if (IS_ERR(tmp))
2149                         return tmp;
2150                 prefer = tmp;
2151         }
2152
2153         return prefer;
2154 }
2155
2156 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2157                                                      const struct flowi *fl,
2158                                                      u16 family, u8 dir,
2159                                                      u32 if_id)
2160 {
2161         struct xfrm_pol_inexact_candidates cand;
2162         const xfrm_address_t *daddr, *saddr;
2163         struct xfrm_pol_inexact_bin *bin;
2164         struct xfrm_policy *pol, *ret;
2165         struct hlist_head *chain;
2166         unsigned int sequence;
2167         int err;
2168
2169         daddr = xfrm_flowi_daddr(fl, family);
2170         saddr = xfrm_flowi_saddr(fl, family);
2171         if (unlikely(!daddr || !saddr))
2172                 return NULL;
2173
2174         rcu_read_lock();
2175  retry:
2176         do {
2177                 sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2178                 chain = policy_hash_direct(net, daddr, saddr, family, dir);
2179         } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2180
2181         ret = NULL;
2182         hlist_for_each_entry_rcu(pol, chain, bydst) {
2183                 err = xfrm_policy_match(pol, fl, type, family, if_id);
2184                 if (err) {
2185                         if (err == -ESRCH)
2186                                 continue;
2187                         else {
2188                                 ret = ERR_PTR(err);
2189                                 goto fail;
2190                         }
2191                 } else {
2192                         ret = pol;
2193                         break;
2194                 }
2195         }
2196         if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
2197                 goto skip_inexact;
2198
2199         bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2200         if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2201                                                          daddr))
2202                 goto skip_inexact;
2203
2204         pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2205                                           family, if_id);
2206         if (pol) {
2207                 ret = pol;
2208                 if (IS_ERR(pol))
2209                         goto fail;
2210         }
2211
2212 skip_inexact:
2213         if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2214                 goto retry;
2215
2216         if (ret && !xfrm_pol_hold_rcu(ret))
2217                 goto retry;
2218 fail:
2219         rcu_read_unlock();
2220
2221         return ret;
2222 }
2223
2224 static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2225                                               const struct flowi *fl,
2226                                               u16 family, u8 dir, u32 if_id)
2227 {
2228 #ifdef CONFIG_XFRM_SUB_POLICY
2229         struct xfrm_policy *pol;
2230
2231         pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2232                                         dir, if_id);
2233         if (pol != NULL)
2234                 return pol;
2235 #endif
2236         return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2237                                          dir, if_id);
2238 }
2239
2240 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2241                                                  const struct flowi *fl,
2242                                                  u16 family, u32 if_id)
2243 {
2244         struct xfrm_policy *pol;
2245
2246         rcu_read_lock();
2247  again:
2248         pol = rcu_dereference(sk->sk_policy[dir]);
2249         if (pol != NULL) {
2250                 bool match;
2251                 int err = 0;
2252
2253                 if (pol->family != family) {
2254                         pol = NULL;
2255                         goto out;
2256                 }
2257
2258                 match = xfrm_selector_match(&pol->selector, fl, family);
2259                 if (match) {
2260                         if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v ||
2261                             pol->if_id != if_id) {
2262                                 pol = NULL;
2263                                 goto out;
2264                         }
2265                         err = security_xfrm_policy_lookup(pol->security,
2266                                                       fl->flowi_secid);
2267                         if (!err) {
2268                                 if (!xfrm_pol_hold_rcu(pol))
2269                                         goto again;
2270                         } else if (err == -ESRCH) {
2271                                 pol = NULL;
2272                         } else {
2273                                 pol = ERR_PTR(err);
2274                         }
2275                 } else
2276                         pol = NULL;
2277         }
2278 out:
2279         rcu_read_unlock();
2280         return pol;
2281 }
2282
2283 static u32 xfrm_gen_pos_slow(struct net *net)
2284 {
2285         struct xfrm_policy *policy;
2286         u32 i = 0;
2287
2288         /* oldest entry is last in list */
2289         list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
2290                 if (!xfrm_policy_is_dead_or_sk(policy))
2291                         policy->pos = ++i;
2292         }
2293
2294         return i;
2295 }
2296
2297 static u32 xfrm_gen_pos(struct net *net)
2298 {
2299         const struct xfrm_policy *policy;
2300         u32 i = 0;
2301
2302         /* most recently added policy is at the head of the list */
2303         list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
2304                 if (xfrm_policy_is_dead_or_sk(policy))
2305                         continue;
2306
2307                 if (policy->pos == UINT_MAX)
2308                         return xfrm_gen_pos_slow(net);
2309
2310                 i = policy->pos + 1;
2311                 break;
2312         }
2313
2314         return i;
2315 }
2316
2317 static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2318 {
2319         struct net *net = xp_net(pol);
2320
2321         switch (dir) {
2322         case XFRM_POLICY_IN:
2323         case XFRM_POLICY_FWD:
2324         case XFRM_POLICY_OUT:
2325                 pol->pos = xfrm_gen_pos(net);
2326                 break;
2327         }
2328
2329         list_add(&pol->walk.all, &net->xfrm.policy_all);
2330         net->xfrm.policy_count[dir]++;
2331         xfrm_pol_hold(pol);
2332 }
2333
2334 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2335                                                 int dir)
2336 {
2337         struct net *net = xp_net(pol);
2338
2339         if (list_empty(&pol->walk.all))
2340                 return NULL;
2341
2342         /* Socket policies are not hashed. */
2343         if (!hlist_unhashed(&pol->bydst)) {
2344                 hlist_del_rcu(&pol->bydst);
2345                 hlist_del(&pol->byidx);
2346         }
2347
2348         list_del_init(&pol->walk.all);
2349         net->xfrm.policy_count[dir]--;
2350
2351         return pol;
2352 }
2353
2354 static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2355 {
2356         __xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2357 }
2358
2359 static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2360 {
2361         __xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2362 }
2363
2364 int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2365 {
2366         struct net *net = xp_net(pol);
2367
2368         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2369         pol = __xfrm_policy_unlink(pol, dir);
2370         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2371         if (pol) {
2372                 xfrm_policy_kill(pol);
2373                 return 0;
2374         }
2375         return -ENOENT;
2376 }
2377 EXPORT_SYMBOL(xfrm_policy_delete);
2378
2379 int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2380 {
2381         struct net *net = sock_net(sk);
2382         struct xfrm_policy *old_pol;
2383
2384 #ifdef CONFIG_XFRM_SUB_POLICY
2385         if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2386                 return -EINVAL;
2387 #endif
2388
2389         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2390         old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2391                                 lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2392         if (pol) {
2393                 pol->curlft.add_time = ktime_get_real_seconds();
2394                 pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2395                 xfrm_sk_policy_link(pol, dir);
2396         }
2397         rcu_assign_pointer(sk->sk_policy[dir], pol);
2398         if (old_pol) {
2399                 if (pol)
2400                         xfrm_policy_requeue(old_pol, pol);
2401
2402                 /* Unlinking succeeds always. This is the only function
2403                  * allowed to delete or replace socket policy.
2404                  */
2405                 xfrm_sk_policy_unlink(old_pol, dir);
2406         }
2407         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2408
2409         if (old_pol) {
2410                 xfrm_policy_kill(old_pol);
2411         }
2412         return 0;
2413 }
2414
2415 static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2416 {
2417         struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2418         struct net *net = xp_net(old);
2419
2420         if (newp) {
2421                 newp->selector = old->selector;
2422                 if (security_xfrm_policy_clone(old->security,
2423                                                &newp->security)) {
2424                         kfree(newp);
2425                         return NULL;  /* ENOMEM */
2426                 }
2427                 newp->lft = old->lft;
2428                 newp->curlft = old->curlft;
2429                 newp->mark = old->mark;
2430                 newp->if_id = old->if_id;
2431                 newp->action = old->action;
2432                 newp->flags = old->flags;
2433                 newp->xfrm_nr = old->xfrm_nr;
2434                 newp->index = old->index;
2435                 newp->type = old->type;
2436                 newp->family = old->family;
2437                 memcpy(newp->xfrm_vec, old->xfrm_vec,
2438                        newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2439                 spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2440                 xfrm_sk_policy_link(newp, dir);
2441                 spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2442                 xfrm_pol_put(newp);
2443         }
2444         return newp;
2445 }
2446
2447 int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2448 {
2449         const struct xfrm_policy *p;
2450         struct xfrm_policy *np;
2451         int i, ret = 0;
2452
2453         rcu_read_lock();
2454         for (i = 0; i < 2; i++) {
2455                 p = rcu_dereference(osk->sk_policy[i]);
2456                 if (p) {
2457                         np = clone_policy(p, i);
2458                         if (unlikely(!np)) {
2459                                 ret = -ENOMEM;
2460                                 break;
2461                         }
2462                         rcu_assign_pointer(sk->sk_policy[i], np);
2463                 }
2464         }
2465         rcu_read_unlock();
2466         return ret;
2467 }
2468
2469 static int
2470 xfrm_get_saddr(unsigned short family, xfrm_address_t *saddr,
2471                const struct xfrm_dst_lookup_params *params)
2472 {
2473         int err;
2474         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2475
2476         if (unlikely(afinfo == NULL))
2477                 return -EINVAL;
2478         err = afinfo->get_saddr(saddr, params);
2479         rcu_read_unlock();
2480         return err;
2481 }
2482
2483 /* Resolve list of templates for the flow, given policy. */
2484
2485 static int
2486 xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2487                       struct xfrm_state **xfrm, unsigned short family)
2488 {
2489         struct net *net = xp_net(policy);
2490         int nx;
2491         int i, error;
2492         xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2493         xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2494         xfrm_address_t tmp;
2495
2496         for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2497                 struct xfrm_state *x;
2498                 xfrm_address_t *remote = daddr;
2499                 xfrm_address_t *local  = saddr;
2500                 struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2501
2502                 if (tmpl->mode == XFRM_MODE_TUNNEL ||
2503                     tmpl->mode == XFRM_MODE_IPTFS ||
2504                     tmpl->mode == XFRM_MODE_BEET) {
2505                         remote = &tmpl->id.daddr;
2506                         local = &tmpl->saddr;
2507                         if (xfrm_addr_any(local, tmpl->encap_family)) {
2508                                 struct xfrm_dst_lookup_params params;
2509
2510                                 memset(&params, 0, sizeof(params));
2511                                 params.net = net;
2512                                 params.oif = fl->flowi_oif;
2513                                 params.daddr = remote;
2514                                 error = xfrm_get_saddr(tmpl->encap_family, &tmp,
2515                                                        &params);
2516                                 if (error)
2517                                         goto fail;
2518                                 local = &tmp;
2519                         }
2520                 }
2521
2522                 x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2523                                     family, policy->if_id);
2524                 if (x && x->dir && x->dir != XFRM_SA_DIR_OUT) {
2525                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEDIRERROR);
2526                         xfrm_state_put(x);
2527                         error = -EINVAL;
2528                         goto fail;
2529                 }
2530
2531                 if (x && x->km.state == XFRM_STATE_VALID) {
2532                         xfrm[nx++] = x;
2533                         daddr = remote;
2534                         saddr = local;
2535                         continue;
2536                 }
2537                 if (x) {
2538                         error = (x->km.state == XFRM_STATE_ERROR ?
2539                                  -EINVAL : -EAGAIN);
2540                         xfrm_state_put(x);
2541                 } else if (error == -ESRCH) {
2542                         error = -EAGAIN;
2543                 }
2544
2545                 if (!tmpl->optional)
2546                         goto fail;
2547         }
2548         return nx;
2549
2550 fail:
2551         for (nx--; nx >= 0; nx--)
2552                 xfrm_state_put(xfrm[nx]);
2553         return error;
2554 }
2555
2556 static int
2557 xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2558                   struct xfrm_state **xfrm, unsigned short family)
2559 {
2560         struct xfrm_state *tp[XFRM_MAX_DEPTH];
2561         struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2562         int cnx = 0;
2563         int error;
2564         int ret;
2565         int i;
2566
2567         for (i = 0; i < npols; i++) {
2568                 if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2569                         error = -ENOBUFS;
2570                         goto fail;
2571                 }
2572
2573                 ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2574                 if (ret < 0) {
2575                         error = ret;
2576                         goto fail;
2577                 } else
2578                         cnx += ret;
2579         }
2580
2581         /* found states are sorted for outbound processing */
2582         if (npols > 1)
2583                 xfrm_state_sort(xfrm, tpp, cnx, family);
2584
2585         return cnx;
2586
2587  fail:
2588         for (cnx--; cnx >= 0; cnx--)
2589                 xfrm_state_put(tpp[cnx]);
2590         return error;
2591
2592 }
2593
2594 static dscp_t xfrm_get_dscp(const struct flowi *fl, int family)
2595 {
2596         if (family == AF_INET)
2597                 return inet_dsfield_to_dscp(fl->u.ip4.flowi4_tos);
2598
2599         return 0;
2600 }
2601
2602 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2603 {
2604         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2605         struct dst_ops *dst_ops;
2606         struct xfrm_dst *xdst;
2607
2608         if (!afinfo)
2609                 return ERR_PTR(-EINVAL);
2610
2611         switch (family) {
2612         case AF_INET:
2613                 dst_ops = &net->xfrm.xfrm4_dst_ops;
2614                 break;
2615 #if IS_ENABLED(CONFIG_IPV6)
2616         case AF_INET6:
2617                 dst_ops = &net->xfrm.xfrm6_dst_ops;
2618                 break;
2619 #endif
2620         default:
2621                 BUG();
2622         }
2623         xdst = dst_alloc(dst_ops, NULL, DST_OBSOLETE_NONE, 0);
2624
2625         if (likely(xdst)) {
2626                 memset_after(xdst, 0, u.dst);
2627         } else
2628                 xdst = ERR_PTR(-ENOBUFS);
2629
2630         rcu_read_unlock();
2631
2632         return xdst;
2633 }
2634
2635 static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2636                            int nfheader_len)
2637 {
2638         if (dst->ops->family == AF_INET6) {
2639                 path->path_cookie = rt6_get_cookie(dst_rt6_info(dst));
2640                 path->u.rt6.rt6i_nfheader_len = nfheader_len;
2641         }
2642 }
2643
2644 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2645                                 const struct flowi *fl)
2646 {
2647         const struct xfrm_policy_afinfo *afinfo =
2648                 xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2649         int err;
2650
2651         if (!afinfo)
2652                 return -EINVAL;
2653
2654         err = afinfo->fill_dst(xdst, dev, fl);
2655
2656         rcu_read_unlock();
2657
2658         return err;
2659 }
2660
2661
2662 /* Allocate chain of dst_entry's, attach known xfrm's, calculate
2663  * all the metrics... Shortly, bundle a bundle.
2664  */
2665
2666 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2667                                             struct xfrm_state **xfrm,
2668                                             struct xfrm_dst **bundle,
2669                                             int nx,
2670                                             const struct flowi *fl,
2671                                             struct dst_entry *dst)
2672 {
2673         const struct xfrm_state_afinfo *afinfo;
2674         const struct xfrm_mode *inner_mode;
2675         struct net *net = xp_net(policy);
2676         unsigned long now = jiffies;
2677         struct net_device *dev;
2678         struct xfrm_dst *xdst_prev = NULL;
2679         struct xfrm_dst *xdst0 = NULL;
2680         int i = 0;
2681         int err;
2682         int header_len = 0;
2683         int nfheader_len = 0;
2684         int trailer_len = 0;
2685         int family = policy->selector.family;
2686         xfrm_address_t saddr, daddr;
2687         dscp_t dscp;
2688
2689         xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2690
2691         dscp = xfrm_get_dscp(fl, family);
2692
2693         dst_hold(dst);
2694
2695         for (; i < nx; i++) {
2696                 struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2697                 struct dst_entry *dst1 = &xdst->u.dst;
2698
2699                 err = PTR_ERR(xdst);
2700                 if (IS_ERR(xdst)) {
2701                         dst_release(dst);
2702                         goto put_states;
2703                 }
2704
2705                 bundle[i] = xdst;
2706                 if (!xdst_prev)
2707                         xdst0 = xdst;
2708                 else
2709                         /* Ref count is taken during xfrm_alloc_dst()
2710                          * No need to do dst_clone() on dst1
2711                          */
2712                         xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2713
2714                 if (xfrm[i]->sel.family == AF_UNSPEC) {
2715                         inner_mode = xfrm_ip2inner_mode(xfrm[i],
2716                                                         xfrm_af2proto(family));
2717                         if (!inner_mode) {
2718                                 err = -EAFNOSUPPORT;
2719                                 dst_release(dst);
2720                                 goto put_states;
2721                         }
2722                 } else
2723                         inner_mode = &xfrm[i]->inner_mode;
2724
2725                 xdst->route = dst;
2726                 dst_copy_metrics(dst1, dst);
2727
2728                 if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2729                         __u32 mark = 0;
2730                         int oif;
2731
2732                         if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2733                                 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2734
2735                         if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET)
2736                                 family = xfrm[i]->props.family;
2737
2738                         oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2739                         dst = xfrm_dst_lookup(xfrm[i], dscp, oif, &saddr,
2740                                               &daddr, family, mark);
2741                         err = PTR_ERR(dst);
2742                         if (IS_ERR(dst))
2743                                 goto put_states;
2744                 } else
2745                         dst_hold(dst);
2746
2747                 dst1->xfrm = xfrm[i];
2748                 xdst->xfrm_genid = xfrm[i]->genid;
2749
2750                 dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2751                 dst1->lastuse = now;
2752
2753                 dst1->input = dst_discard;
2754
2755                 if (xfrm[i]->mode_cbs && xfrm[i]->mode_cbs->output) {
2756                         dst1->output = xfrm[i]->mode_cbs->output;
2757                 } else {
2758                         rcu_read_lock();
2759                         afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2760                         if (likely(afinfo))
2761                                 dst1->output = afinfo->output;
2762                         else
2763                                 dst1->output = dst_discard_out;
2764                         rcu_read_unlock();
2765                 }
2766
2767                 xdst_prev = xdst;
2768
2769                 header_len += xfrm[i]->props.header_len;
2770                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2771                         nfheader_len += xfrm[i]->props.header_len;
2772                 trailer_len += xfrm[i]->props.trailer_len;
2773         }
2774
2775         xfrm_dst_set_child(xdst_prev, dst);
2776         xdst0->path = dst;
2777
2778         err = -ENODEV;
2779         dev = dst->dev;
2780         if (!dev)
2781                 goto free_dst;
2782
2783         xfrm_init_path(xdst0, dst, nfheader_len);
2784         xfrm_init_pmtu(bundle, nx);
2785
2786         for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2787              xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2788                 err = xfrm_fill_dst(xdst_prev, dev, fl);
2789                 if (err)
2790                         goto free_dst;
2791
2792                 xdst_prev->u.dst.header_len = header_len;
2793                 xdst_prev->u.dst.trailer_len = trailer_len;
2794                 header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2795                 trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2796         }
2797
2798         return &xdst0->u.dst;
2799
2800 put_states:
2801         for (; i < nx; i++)
2802                 xfrm_state_put(xfrm[i]);
2803 free_dst:
2804         if (xdst0)
2805                 dst_release_immediate(&xdst0->u.dst);
2806
2807         return ERR_PTR(err);
2808 }
2809
2810 static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2811                                 struct xfrm_policy **pols,
2812                                 int *num_pols, int *num_xfrms)
2813 {
2814         int i;
2815
2816         if (*num_pols == 0 || !pols[0]) {
2817                 *num_pols = 0;
2818                 *num_xfrms = 0;
2819                 return 0;
2820         }
2821         if (IS_ERR(pols[0])) {
2822                 *num_pols = 0;
2823                 return PTR_ERR(pols[0]);
2824         }
2825
2826         *num_xfrms = pols[0]->xfrm_nr;
2827
2828 #ifdef CONFIG_XFRM_SUB_POLICY
2829         if (pols[0]->action == XFRM_POLICY_ALLOW &&
2830             pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2831                 pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2832                                                     XFRM_POLICY_TYPE_MAIN,
2833                                                     fl, family,
2834                                                     XFRM_POLICY_OUT,
2835                                                     pols[0]->if_id);
2836                 if (pols[1]) {
2837                         if (IS_ERR(pols[1])) {
2838                                 xfrm_pols_put(pols, *num_pols);
2839                                 *num_pols = 0;
2840                                 return PTR_ERR(pols[1]);
2841                         }
2842                         (*num_pols)++;
2843                         (*num_xfrms) += pols[1]->xfrm_nr;
2844                 }
2845         }
2846 #endif
2847         for (i = 0; i < *num_pols; i++) {
2848                 if (pols[i]->action != XFRM_POLICY_ALLOW) {
2849                         *num_xfrms = -1;
2850                         break;
2851                 }
2852         }
2853
2854         return 0;
2855
2856 }
2857
2858 static struct xfrm_dst *
2859 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2860                                const struct flowi *fl, u16 family,
2861                                struct dst_entry *dst_orig)
2862 {
2863         struct net *net = xp_net(pols[0]);
2864         struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2865         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2866         struct xfrm_dst *xdst;
2867         struct dst_entry *dst;
2868         int err;
2869
2870         /* Try to instantiate a bundle */
2871         err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2872         if (err <= 0) {
2873                 if (err == 0)
2874                         return NULL;
2875
2876                 if (err != -EAGAIN)
2877                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2878                 return ERR_PTR(err);
2879         }
2880
2881         dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2882         if (IS_ERR(dst)) {
2883                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2884                 return ERR_CAST(dst);
2885         }
2886
2887         xdst = (struct xfrm_dst *)dst;
2888         xdst->num_xfrms = err;
2889         xdst->num_pols = num_pols;
2890         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2891         xdst->policy_genid = atomic_read(&pols[0]->genid);
2892
2893         return xdst;
2894 }
2895
2896 static void xfrm_policy_queue_process(struct timer_list *t)
2897 {
2898         struct sk_buff *skb;
2899         struct sock *sk;
2900         struct dst_entry *dst;
2901         struct xfrm_policy *pol = timer_container_of(pol, t, polq.hold_timer);
2902         struct net *net = xp_net(pol);
2903         struct xfrm_policy_queue *pq = &pol->polq;
2904         struct flowi fl;
2905         struct sk_buff_head list;
2906         __u32 skb_mark;
2907
2908         spin_lock(&pq->hold_queue.lock);
2909         skb = skb_peek(&pq->hold_queue);
2910         if (!skb) {
2911                 spin_unlock(&pq->hold_queue.lock);
2912                 goto out;
2913         }
2914         dst = skb_dst(skb);
2915         sk = skb->sk;
2916
2917         /* Fixup the mark to support VTI. */
2918         skb_mark = skb->mark;
2919         skb->mark = pol->mark.v;
2920         xfrm_decode_session(net, skb, &fl, dst->ops->family);
2921         skb->mark = skb_mark;
2922         spin_unlock(&pq->hold_queue.lock);
2923
2924         dst_hold(xfrm_dst_path(dst));
2925         dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2926         if (IS_ERR(dst))
2927                 goto purge_queue;
2928
2929         if (dst->flags & DST_XFRM_QUEUE) {
2930                 dst_release(dst);
2931
2932                 if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2933                         goto purge_queue;
2934
2935                 pq->timeout = pq->timeout << 1;
2936                 if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2937                         xfrm_pol_hold(pol);
2938                 goto out;
2939         }
2940
2941         dst_release(dst);
2942
2943         __skb_queue_head_init(&list);
2944
2945         spin_lock(&pq->hold_queue.lock);
2946         pq->timeout = 0;
2947         skb_queue_splice_init(&pq->hold_queue, &list);
2948         spin_unlock(&pq->hold_queue.lock);
2949
2950         while (!skb_queue_empty(&list)) {
2951                 skb = __skb_dequeue(&list);
2952
2953                 /* Fixup the mark to support VTI. */
2954                 skb_mark = skb->mark;
2955                 skb->mark = pol->mark.v;
2956                 xfrm_decode_session(net, skb, &fl, skb_dst(skb)->ops->family);
2957                 skb->mark = skb_mark;
2958
2959                 dst_hold(xfrm_dst_path(skb_dst(skb)));
2960                 dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2961                 if (IS_ERR(dst)) {
2962                         kfree_skb(skb);
2963                         continue;
2964                 }
2965
2966                 nf_reset_ct(skb);
2967                 skb_dst_drop(skb);
2968                 skb_dst_set(skb, dst);
2969
2970                 dst_output(net, skb_to_full_sk(skb), skb);
2971         }
2972
2973 out:
2974         xfrm_pol_put(pol);
2975         return;
2976
2977 purge_queue:
2978         pq->timeout = 0;
2979         skb_queue_purge(&pq->hold_queue);
2980         xfrm_pol_put(pol);
2981 }
2982
2983 static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2984 {
2985         unsigned long sched_next;
2986         struct dst_entry *dst = skb_dst(skb);
2987         struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2988         struct xfrm_policy *pol = xdst->pols[0];
2989         struct xfrm_policy_queue *pq = &pol->polq;
2990
2991         if (unlikely(skb_fclone_busy(sk, skb))) {
2992                 kfree_skb(skb);
2993                 return 0;
2994         }
2995
2996         if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2997                 kfree_skb(skb);
2998                 return -EAGAIN;
2999         }
3000
3001         skb_dst_force(skb);
3002
3003         spin_lock_bh(&pq->hold_queue.lock);
3004
3005         if (!pq->timeout)
3006                 pq->timeout = XFRM_QUEUE_TMO_MIN;
3007
3008         sched_next = jiffies + pq->timeout;
3009
3010         if (timer_delete(&pq->hold_timer)) {
3011                 if (time_before(pq->hold_timer.expires, sched_next))
3012                         sched_next = pq->hold_timer.expires;
3013                 xfrm_pol_put(pol);
3014         }
3015
3016         __skb_queue_tail(&pq->hold_queue, skb);
3017         if (!mod_timer(&pq->hold_timer, sched_next))
3018                 xfrm_pol_hold(pol);
3019
3020         spin_unlock_bh(&pq->hold_queue.lock);
3021
3022         return 0;
3023 }
3024
3025 static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
3026                                                  struct xfrm_flo *xflo,
3027                                                  const struct flowi *fl,
3028                                                  int num_xfrms,
3029                                                  u16 family)
3030 {
3031         int err;
3032         struct net_device *dev;
3033         struct dst_entry *dst;
3034         struct dst_entry *dst1;
3035         struct xfrm_dst *xdst;
3036
3037         xdst = xfrm_alloc_dst(net, family);
3038         if (IS_ERR(xdst))
3039                 return xdst;
3040
3041         if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
3042             net->xfrm.sysctl_larval_drop ||
3043             num_xfrms <= 0)
3044                 return xdst;
3045
3046         dst = xflo->dst_orig;
3047         dst1 = &xdst->u.dst;
3048         dst_hold(dst);
3049         xdst->route = dst;
3050
3051         dst_copy_metrics(dst1, dst);
3052
3053         dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
3054         dst1->flags |= DST_XFRM_QUEUE;
3055         dst1->lastuse = jiffies;
3056
3057         dst1->input = dst_discard;
3058         dst1->output = xdst_queue_output;
3059
3060         dst_hold(dst);
3061         xfrm_dst_set_child(xdst, dst);
3062         xdst->path = dst;
3063
3064         xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
3065
3066         err = -ENODEV;
3067         dev = dst->dev;
3068         if (!dev)
3069                 goto free_dst;
3070
3071         err = xfrm_fill_dst(xdst, dev, fl);
3072         if (err)
3073                 goto free_dst;
3074
3075 out:
3076         return xdst;
3077
3078 free_dst:
3079         dst_release(dst1);
3080         xdst = ERR_PTR(err);
3081         goto out;
3082 }
3083
3084 static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
3085                                            const struct flowi *fl,
3086                                            u16 family, u8 dir,
3087                                            struct xfrm_flo *xflo, u32 if_id)
3088 {
3089         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3090         int num_pols = 0, num_xfrms = 0, err;
3091         struct xfrm_dst *xdst;
3092
3093         /* Resolve policies to use if we couldn't get them from
3094          * previous cache entry */
3095         num_pols = 1;
3096         pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
3097         err = xfrm_expand_policies(fl, family, pols,
3098                                            &num_pols, &num_xfrms);
3099         if (err < 0)
3100                 goto inc_error;
3101         if (num_pols == 0)
3102                 return NULL;
3103         if (num_xfrms <= 0)
3104                 goto make_dummy_bundle;
3105
3106         xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
3107                                               xflo->dst_orig);
3108         if (IS_ERR(xdst)) {
3109                 err = PTR_ERR(xdst);
3110                 if (err == -EREMOTE) {
3111                         xfrm_pols_put(pols, num_pols);
3112                         return NULL;
3113                 }
3114
3115                 if (err != -EAGAIN)
3116                         goto error;
3117                 goto make_dummy_bundle;
3118         } else if (xdst == NULL) {
3119                 num_xfrms = 0;
3120                 goto make_dummy_bundle;
3121         }
3122
3123         return xdst;
3124
3125 make_dummy_bundle:
3126         /* We found policies, but there's no bundles to instantiate:
3127          * either because the policy blocks, has no transformations or
3128          * we could not build template (no xfrm_states).*/
3129         xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
3130         if (IS_ERR(xdst)) {
3131                 xfrm_pols_put(pols, num_pols);
3132                 return ERR_CAST(xdst);
3133         }
3134         xdst->num_pols = num_pols;
3135         xdst->num_xfrms = num_xfrms;
3136         memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
3137
3138         return xdst;
3139
3140 inc_error:
3141         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3142 error:
3143         xfrm_pols_put(pols, num_pols);
3144         return ERR_PTR(err);
3145 }
3146
3147 static struct dst_entry *make_blackhole(struct net *net, u16 family,
3148                                         struct dst_entry *dst_orig)
3149 {
3150         const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3151         struct dst_entry *ret;
3152
3153         if (!afinfo) {
3154                 dst_release(dst_orig);
3155                 return ERR_PTR(-EINVAL);
3156         } else {
3157                 ret = afinfo->blackhole_route(net, dst_orig);
3158         }
3159         rcu_read_unlock();
3160
3161         return ret;
3162 }
3163
3164 /* Finds/creates a bundle for given flow and if_id
3165  *
3166  * At the moment we eat a raw IP route. Mostly to speed up lookups
3167  * on interfaces with disabled IPsec.
3168  *
3169  * xfrm_lookup uses an if_id of 0 by default, and is provided for
3170  * compatibility
3171  */
3172 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3173                                         struct dst_entry *dst_orig,
3174                                         const struct flowi *fl,
3175                                         const struct sock *sk,
3176                                         int flags, u32 if_id)
3177 {
3178         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3179         struct xfrm_dst *xdst;
3180         struct dst_entry *dst, *route;
3181         u16 family = dst_orig->ops->family;
3182         u8 dir = XFRM_POLICY_OUT;
3183         int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3184
3185         dst = NULL;
3186         xdst = NULL;
3187         route = NULL;
3188
3189         sk = sk_const_to_full_sk(sk);
3190         if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3191                 num_pols = 1;
3192                 pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3193                                                 if_id);
3194                 err = xfrm_expand_policies(fl, family, pols,
3195                                            &num_pols, &num_xfrms);
3196                 if (err < 0)
3197                         goto dropdst;
3198
3199                 if (num_pols) {
3200                         if (num_xfrms <= 0) {
3201                                 drop_pols = num_pols;
3202                                 goto no_transform;
3203                         }
3204
3205                         xdst = xfrm_resolve_and_create_bundle(
3206                                         pols, num_pols, fl,
3207                                         family, dst_orig);
3208
3209                         if (IS_ERR(xdst)) {
3210                                 xfrm_pols_put(pols, num_pols);
3211                                 err = PTR_ERR(xdst);
3212                                 if (err == -EREMOTE)
3213                                         goto nopol;
3214
3215                                 goto dropdst;
3216                         } else if (xdst == NULL) {
3217                                 num_xfrms = 0;
3218                                 drop_pols = num_pols;
3219                                 goto no_transform;
3220                         }
3221
3222                         route = xdst->route;
3223                 }
3224         }
3225
3226         if (xdst == NULL) {
3227                 struct xfrm_flo xflo;
3228
3229                 xflo.dst_orig = dst_orig;
3230                 xflo.flags = flags;
3231
3232                 /* To accelerate a bit...  */
3233                 if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3234                                !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3235                         goto nopol;
3236
3237                 xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3238                 if (xdst == NULL)
3239                         goto nopol;
3240                 if (IS_ERR(xdst)) {
3241                         err = PTR_ERR(xdst);
3242                         goto dropdst;
3243                 }
3244
3245                 num_pols = xdst->num_pols;
3246                 num_xfrms = xdst->num_xfrms;
3247                 memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3248                 route = xdst->route;
3249         }
3250
3251         dst = &xdst->u.dst;
3252         if (route == NULL && num_xfrms > 0) {
3253                 /* The only case when xfrm_bundle_lookup() returns a
3254                  * bundle with null route, is when the template could
3255                  * not be resolved. It means policies are there, but
3256                  * bundle could not be created, since we don't yet
3257                  * have the xfrm_state's. We need to wait for KM to
3258                  * negotiate new SA's or bail out with error.*/
3259                 if (net->xfrm.sysctl_larval_drop) {
3260                         XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3261                         err = -EREMOTE;
3262                         goto error;
3263                 }
3264
3265                 err = -EAGAIN;
3266
3267                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3268                 goto error;
3269         }
3270
3271 no_transform:
3272         if (num_pols == 0)
3273                 goto nopol;
3274
3275         if ((flags & XFRM_LOOKUP_ICMP) &&
3276             !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3277                 err = -ENOENT;
3278                 goto error;
3279         }
3280
3281         for (i = 0; i < num_pols; i++)
3282                 WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds());
3283
3284         if (num_xfrms < 0) {
3285                 /* Prohibit the flow */
3286                 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3287                 err = -EPERM;
3288                 goto error;
3289         } else if (num_xfrms > 0) {
3290                 /* Flow transformed */
3291                 dst_release(dst_orig);
3292         } else {
3293                 /* Flow passes untransformed */
3294                 dst_release(dst);
3295                 dst = dst_orig;
3296         }
3297
3298 ok:
3299         xfrm_pols_put(pols, drop_pols);
3300         if (dst->xfrm &&
3301             (dst->xfrm->props.mode == XFRM_MODE_TUNNEL ||
3302              dst->xfrm->props.mode == XFRM_MODE_IPTFS))
3303                 dst->flags |= DST_XFRM_TUNNEL;
3304         return dst;
3305
3306 nopol:
3307         if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3308             net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3309                 err = -EPERM;
3310                 goto error;
3311         }
3312         if (!(flags & XFRM_LOOKUP_ICMP)) {
3313                 dst = dst_orig;
3314                 goto ok;
3315         }
3316         err = -ENOENT;
3317 error:
3318         dst_release(dst);
3319 dropdst:
3320         if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3321                 dst_release(dst_orig);
3322         xfrm_pols_put(pols, drop_pols);
3323         return ERR_PTR(err);
3324 }
3325 EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3326
3327 /* Main function: finds/creates a bundle for given flow.
3328  *
3329  * At the moment we eat a raw IP route. Mostly to speed up lookups
3330  * on interfaces with disabled IPsec.
3331  */
3332 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3333                               const struct flowi *fl, const struct sock *sk,
3334                               int flags)
3335 {
3336         return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3337 }
3338 EXPORT_SYMBOL(xfrm_lookup);
3339
3340 /* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3341  * Otherwise we may send out blackholed packets.
3342  */
3343 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3344                                     const struct flowi *fl,
3345                                     const struct sock *sk, int flags)
3346 {
3347         struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3348                                             flags | XFRM_LOOKUP_QUEUE |
3349                                             XFRM_LOOKUP_KEEP_DST_REF);
3350
3351         if (PTR_ERR(dst) == -EREMOTE)
3352                 return make_blackhole(net, dst_orig->ops->family, dst_orig);
3353
3354         if (IS_ERR(dst))
3355                 dst_release(dst_orig);
3356
3357         return dst;
3358 }
3359 EXPORT_SYMBOL(xfrm_lookup_route);
3360
3361 static inline int
3362 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3363 {
3364         struct sec_path *sp = skb_sec_path(skb);
3365         struct xfrm_state *x;
3366
3367         if (!sp || idx < 0 || idx >= sp->len)
3368                 return 0;
3369         x = sp->xvec[idx];
3370         if (!x->type->reject)
3371                 return 0;
3372         return x->type->reject(x, skb, fl);
3373 }
3374
3375 /* When skb is transformed back to its "native" form, we have to
3376  * check policy restrictions. At the moment we make this in maximally
3377  * stupid way. Shame on me. :-) Of course, connected sockets must
3378  * have policy cached at them.
3379  */
3380
3381 static inline int
3382 xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3383               unsigned short family, u32 if_id)
3384 {
3385         if (xfrm_state_kern(x))
3386                 return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3387         return  x->id.proto == tmpl->id.proto &&
3388                 (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3389                 (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3390                 x->props.mode == tmpl->mode &&
3391                 (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3392                  !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3393                 !(x->props.mode != XFRM_MODE_TRANSPORT &&
3394                   xfrm_state_addr_cmp(tmpl, x, family)) &&
3395                 (if_id == 0 || if_id == x->if_id);
3396 }
3397
3398 /*
3399  * 0 or more than 0 is returned when validation is succeeded (either bypass
3400  * because of optional transport mode, or next index of the matched secpath
3401  * state with the template.
3402  * -1 is returned when no matching template is found.
3403  * Otherwise "-2 - errored_index" is returned.
3404  */
3405 static inline int
3406 xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3407                unsigned short family, u32 if_id)
3408 {
3409         int idx = start;
3410
3411         if (tmpl->optional) {
3412                 if (tmpl->mode == XFRM_MODE_TRANSPORT)
3413                         return start;
3414         } else
3415                 start = -1;
3416         for (; idx < sp->len; idx++) {
3417                 if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
3418                         return ++idx;
3419                 if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3420                         if (idx < sp->verified_cnt) {
3421                                 /* Secpath entry previously verified, consider optional and
3422                                  * continue searching
3423                                  */
3424                                 continue;
3425                         }
3426
3427                         if (start == -1)
3428                                 start = -2-idx;
3429                         break;
3430                 }
3431         }
3432         return start;
3433 }
3434
3435 static void
3436 decode_session4(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
3437 {
3438         struct flowi4 *fl4 = &fl->u.ip4;
3439
3440         memset(fl4, 0, sizeof(struct flowi4));
3441
3442         if (reverse) {
3443                 fl4->saddr = flkeys->addrs.ipv4.dst;
3444                 fl4->daddr = flkeys->addrs.ipv4.src;
3445                 fl4->fl4_sport = flkeys->ports.dst;
3446                 fl4->fl4_dport = flkeys->ports.src;
3447         } else {
3448                 fl4->saddr = flkeys->addrs.ipv4.src;
3449                 fl4->daddr = flkeys->addrs.ipv4.dst;
3450                 fl4->fl4_sport = flkeys->ports.src;
3451                 fl4->fl4_dport = flkeys->ports.dst;
3452         }
3453
3454         switch (flkeys->basic.ip_proto) {
3455         case IPPROTO_GRE:
3456                 fl4->fl4_gre_key = flkeys->gre.keyid;
3457                 break;
3458         case IPPROTO_ICMP:
3459                 fl4->fl4_icmp_type = flkeys->icmp.type;
3460                 fl4->fl4_icmp_code = flkeys->icmp.code;
3461                 break;
3462         }
3463
3464         fl4->flowi4_proto = flkeys->basic.ip_proto;
3465         fl4->flowi4_tos = flkeys->ip.tos & ~INET_ECN_MASK;
3466 }
3467
3468 #if IS_ENABLED(CONFIG_IPV6)
3469 static void
3470 decode_session6(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
3471 {
3472         struct flowi6 *fl6 = &fl->u.ip6;
3473
3474         memset(fl6, 0, sizeof(struct flowi6));
3475
3476         if (reverse) {
3477                 fl6->saddr = flkeys->addrs.ipv6.dst;
3478                 fl6->daddr = flkeys->addrs.ipv6.src;
3479                 fl6->fl6_sport = flkeys->ports.dst;
3480                 fl6->fl6_dport = flkeys->ports.src;
3481         } else {
3482                 fl6->saddr = flkeys->addrs.ipv6.src;
3483                 fl6->daddr = flkeys->addrs.ipv6.dst;
3484                 fl6->fl6_sport = flkeys->ports.src;
3485                 fl6->fl6_dport = flkeys->ports.dst;
3486         }
3487
3488         switch (flkeys->basic.ip_proto) {
3489         case IPPROTO_GRE:
3490                 fl6->fl6_gre_key = flkeys->gre.keyid;
3491                 break;
3492         case IPPROTO_ICMPV6:
3493                 fl6->fl6_icmp_type = flkeys->icmp.type;
3494                 fl6->fl6_icmp_code = flkeys->icmp.code;
3495                 break;
3496         }
3497
3498         fl6->flowi6_proto = flkeys->basic.ip_proto;
3499 }
3500 #endif
3501
3502 int __xfrm_decode_session(struct net *net, struct sk_buff *skb, struct flowi *fl,
3503                           unsigned int family, int reverse)
3504 {
3505         struct xfrm_flow_keys flkeys;
3506
3507         memset(&flkeys, 0, sizeof(flkeys));
3508         __skb_flow_dissect(net, skb, &xfrm_session_dissector, &flkeys,
3509                            NULL, 0, 0, 0, FLOW_DISSECTOR_F_STOP_AT_ENCAP);
3510
3511         switch (family) {
3512         case AF_INET:
3513                 decode_session4(&flkeys, fl, reverse);
3514                 break;
3515 #if IS_ENABLED(CONFIG_IPV6)
3516         case AF_INET6:
3517                 decode_session6(&flkeys, fl, reverse);
3518                 break;
3519 #endif
3520         default:
3521                 return -EAFNOSUPPORT;
3522         }
3523
3524         fl->flowi_mark = skb->mark;
3525         if (reverse) {
3526                 fl->flowi_oif = skb->skb_iif;
3527         } else {
3528                 int oif = 0;
3529
3530                 if (skb_dst(skb) && skb_dst(skb)->dev)
3531                         oif = skb_dst(skb)->dev->ifindex;
3532
3533                 fl->flowi_oif = oif;
3534         }
3535
3536         return security_xfrm_decode_session(skb, &fl->flowi_secid);
3537 }
3538 EXPORT_SYMBOL(__xfrm_decode_session);
3539
3540 static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3541 {
3542         for (; k < sp->len; k++) {
3543                 if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3544                         *idxp = k;
3545                         return 1;
3546                 }
3547         }
3548
3549         return 0;
3550 }
3551
3552 static bool icmp_err_packet(const struct flowi *fl, unsigned short family)
3553 {
3554         const struct flowi4 *fl4 = &fl->u.ip4;
3555
3556         if (family == AF_INET &&
3557             fl4->flowi4_proto == IPPROTO_ICMP &&
3558             (fl4->fl4_icmp_type == ICMP_DEST_UNREACH ||
3559              fl4->fl4_icmp_type == ICMP_TIME_EXCEEDED))
3560                 return true;
3561
3562 #if IS_ENABLED(CONFIG_IPV6)
3563         if (family == AF_INET6) {
3564                 const struct flowi6 *fl6 = &fl->u.ip6;
3565
3566                 if (fl6->flowi6_proto == IPPROTO_ICMPV6 &&
3567                     (fl6->fl6_icmp_type == ICMPV6_DEST_UNREACH ||
3568                     fl6->fl6_icmp_type == ICMPV6_PKT_TOOBIG ||
3569                     fl6->fl6_icmp_type == ICMPV6_TIME_EXCEED))
3570                         return true;
3571         }
3572 #endif
3573         return false;
3574 }
3575
3576 static bool xfrm_icmp_flow_decode(struct sk_buff *skb, unsigned short family,
3577                                   const struct flowi *fl, struct flowi *fl1)
3578 {
3579         bool ret = true;
3580         struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
3581         int hl = family == AF_INET ? (sizeof(struct iphdr) +  sizeof(struct icmphdr)) :
3582                  (sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr));
3583
3584         if (!newskb)
3585                 return true;
3586
3587         if (!pskb_pull(newskb, hl))
3588                 goto out;
3589
3590         skb_reset_network_header(newskb);
3591
3592         if (xfrm_decode_session_reverse(dev_net(skb->dev), newskb, fl1, family) < 0)
3593                 goto out;
3594
3595         fl1->flowi_oif = fl->flowi_oif;
3596         fl1->flowi_mark = fl->flowi_mark;
3597         fl1->flowi_tos = fl->flowi_tos;
3598         nf_nat_decode_session(newskb, fl1, family);
3599         ret = false;
3600
3601 out:
3602         consume_skb(newskb);
3603         return ret;
3604 }
3605
3606 static bool xfrm_selector_inner_icmp_match(struct sk_buff *skb, unsigned short family,
3607                                            const struct xfrm_selector *sel,
3608                                            const struct flowi *fl)
3609 {
3610         bool ret = false;
3611
3612         if (icmp_err_packet(fl, family)) {
3613                 struct flowi fl1;
3614
3615                 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3616                         return ret;
3617
3618                 ret = xfrm_selector_match(sel, &fl1, family);
3619         }
3620
3621         return ret;
3622 }
3623
3624 static inline struct
3625 xfrm_policy *xfrm_in_fwd_icmp(struct sk_buff *skb,
3626                               const struct flowi *fl, unsigned short family,
3627                               u32 if_id)
3628 {
3629         struct xfrm_policy *pol = NULL;
3630
3631         if (icmp_err_packet(fl, family)) {
3632                 struct flowi fl1;
3633                 struct net *net = dev_net(skb->dev);
3634
3635                 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3636                         return pol;
3637
3638                 pol = xfrm_policy_lookup(net, &fl1, family, XFRM_POLICY_FWD, if_id);
3639                 if (IS_ERR(pol))
3640                         pol = NULL;
3641         }
3642
3643         return pol;
3644 }
3645
3646 static inline struct
3647 dst_entry *xfrm_out_fwd_icmp(struct sk_buff *skb, struct flowi *fl,
3648                              unsigned short family, struct dst_entry *dst)
3649 {
3650         if (icmp_err_packet(fl, family)) {
3651                 struct net *net = dev_net(skb->dev);
3652                 struct dst_entry *dst2;
3653                 struct flowi fl1;
3654
3655                 if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3656                         return dst;
3657
3658                 dst_hold(dst);
3659
3660                 dst2 = xfrm_lookup(net, dst, &fl1, NULL, (XFRM_LOOKUP_QUEUE | XFRM_LOOKUP_ICMP));
3661
3662                 if (IS_ERR(dst2))
3663                         return dst;
3664
3665                 if (dst2->xfrm) {
3666                         dst_release(dst);
3667                         dst = dst2;
3668                 } else {
3669                         dst_release(dst2);
3670                 }
3671         }
3672
3673         return dst;
3674 }
3675
3676 int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3677                         unsigned short family)
3678 {
3679         struct net *net = dev_net(skb->dev);
3680         struct xfrm_policy *pol;
3681         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3682         int npols = 0;
3683         int xfrm_nr;
3684         int pi;
3685         int reverse;
3686         struct flowi fl;
3687         int xerr_idx = -1;
3688         const struct xfrm_if_cb *ifcb;
3689         struct sec_path *sp;
3690         u32 if_id = 0;
3691
3692         rcu_read_lock();
3693         ifcb = xfrm_if_get_cb();
3694
3695         if (ifcb) {
3696                 struct xfrm_if_decode_session_result r;
3697
3698                 if (ifcb->decode_session(skb, family, &r)) {
3699                         if_id = r.if_id;
3700                         net = r.net;
3701                 }
3702         }
3703         rcu_read_unlock();
3704
3705         reverse = dir & ~XFRM_POLICY_MASK;
3706         dir &= XFRM_POLICY_MASK;
3707
3708         if (__xfrm_decode_session(net, skb, &fl, family, reverse) < 0) {
3709                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3710                 return 0;
3711         }
3712
3713         nf_nat_decode_session(skb, &fl, family);
3714
3715         /* First, check used SA against their selectors. */
3716         sp = skb_sec_path(skb);
3717         if (sp) {
3718                 int i;
3719
3720                 for (i = sp->len - 1; i >= 0; i--) {
3721                         struct xfrm_state *x = sp->xvec[i];
3722                         int ret = 0;
3723
3724                         if (!xfrm_selector_match(&x->sel, &fl, family)) {
3725                                 ret = 1;
3726                                 if (x->props.flags & XFRM_STATE_ICMP &&
3727                                     xfrm_selector_inner_icmp_match(skb, family, &x->sel, &fl))
3728                                         ret = 0;
3729                                 if (ret) {
3730                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3731                                         return 0;
3732                                 }
3733                         }
3734                 }
3735         }
3736
3737         pol = NULL;
3738         sk = sk_to_full_sk(sk);
3739         if (sk && sk->sk_policy[dir]) {
3740                 pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3741                 if (IS_ERR(pol)) {
3742                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3743                         return 0;
3744                 }
3745         }
3746
3747         if (!pol)
3748                 pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3749
3750         if (IS_ERR(pol)) {
3751                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3752                 return 0;
3753         }
3754
3755         if (!pol && dir == XFRM_POLICY_FWD)
3756                 pol = xfrm_in_fwd_icmp(skb, &fl, family, if_id);
3757
3758         if (!pol) {
3759                 const bool is_crypto_offload = sp &&
3760                         (xfrm_input_state(skb)->xso.type == XFRM_DEV_OFFLOAD_CRYPTO);
3761
3762                 if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3763                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3764                         return 0;
3765                 }
3766
3767                 if (sp && secpath_has_nontransport(sp, 0, &xerr_idx) && !is_crypto_offload) {
3768                         xfrm_secpath_reject(xerr_idx, skb, &fl);
3769                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3770                         return 0;
3771                 }
3772                 return 1;
3773         }
3774
3775         /* This lockless write can happen from different cpus. */
3776         WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
3777
3778         pols[0] = pol;
3779         npols++;
3780 #ifdef CONFIG_XFRM_SUB_POLICY
3781         if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3782                 pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3783                                                     &fl, family,
3784                                                     XFRM_POLICY_IN, if_id);
3785                 if (pols[1]) {
3786                         if (IS_ERR(pols[1])) {
3787                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3788                                 xfrm_pol_put(pols[0]);
3789                                 return 0;
3790                         }
3791                         /* This write can happen from different cpus. */
3792                         WRITE_ONCE(pols[1]->curlft.use_time,
3793                                    ktime_get_real_seconds());
3794                         npols++;
3795                 }
3796         }
3797 #endif
3798
3799         if (pol->action == XFRM_POLICY_ALLOW) {
3800                 static struct sec_path dummy;
3801                 struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3802                 struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3803                 struct xfrm_tmpl **tpp = tp;
3804                 int ti = 0;
3805                 int i, k;
3806
3807                 sp = skb_sec_path(skb);
3808                 if (!sp)
3809                         sp = &dummy;
3810
3811                 for (pi = 0; pi < npols; pi++) {
3812                         if (pols[pi] != pol &&
3813                             pols[pi]->action != XFRM_POLICY_ALLOW) {
3814                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3815                                 goto reject;
3816                         }
3817                         if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3818                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3819                                 goto reject_error;
3820                         }
3821                         for (i = 0; i < pols[pi]->xfrm_nr; i++)
3822                                 tpp[ti++] = &pols[pi]->xfrm_vec[i];
3823                 }
3824                 xfrm_nr = ti;
3825
3826                 if (npols > 1) {
3827                         xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3828                         tpp = stp;
3829                 }
3830
3831                 /* For each tunnel xfrm, find the first matching tmpl.
3832                  * For each tmpl before that, find corresponding xfrm.
3833                  * Order is _important_. Later we will implement
3834                  * some barriers, but at the moment barriers
3835                  * are implied between each two transformations.
3836                  * Upon success, marks secpath entries as having been
3837                  * verified to allow them to be skipped in future policy
3838                  * checks (e.g. nested tunnels).
3839                  */
3840                 for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3841                         k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
3842                         if (k < 0) {
3843                                 if (k < -1)
3844                                         /* "-2 - errored_index" returned */
3845                                         xerr_idx = -(2+k);
3846                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3847                                 goto reject;
3848                         }
3849                 }
3850
3851                 if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3852                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3853                         goto reject;
3854                 }
3855
3856                 xfrm_pols_put(pols, npols);
3857                 sp->verified_cnt = k;
3858
3859                 return 1;
3860         }
3861         XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3862
3863 reject:
3864         xfrm_secpath_reject(xerr_idx, skb, &fl);
3865 reject_error:
3866         xfrm_pols_put(pols, npols);
3867         return 0;
3868 }
3869 EXPORT_SYMBOL(__xfrm_policy_check);
3870
3871 int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3872 {
3873         struct net *net = dev_net(skb->dev);
3874         struct flowi fl;
3875         struct dst_entry *dst;
3876         int res = 1;
3877
3878         if (xfrm_decode_session(net, skb, &fl, family) < 0) {
3879                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3880                 return 0;
3881         }
3882
3883         skb_dst_force(skb);
3884         if (!skb_dst(skb)) {
3885                 XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3886                 return 0;
3887         }
3888
3889         dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3890         if (IS_ERR(dst)) {
3891                 res = 0;
3892                 dst = NULL;
3893         }
3894
3895         if (dst && !dst->xfrm)
3896                 dst = xfrm_out_fwd_icmp(skb, &fl, family, dst);
3897
3898         skb_dst_set(skb, dst);
3899         return res;
3900 }
3901 EXPORT_SYMBOL(__xfrm_route_forward);
3902
3903 /* Optimize later using cookies and generation ids. */
3904
3905 static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3906 {
3907         /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3908          * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3909          * get validated by dst_ops->check on every use.  We do this
3910          * because when a normal route referenced by an XFRM dst is
3911          * obsoleted we do not go looking around for all parent
3912          * referencing XFRM dsts so that we can invalidate them.  It
3913          * is just too much work.  Instead we make the checks here on
3914          * every use.  For example:
3915          *
3916          *      XFRM dst A --> IPv4 dst X
3917          *
3918          * X is the "xdst->route" of A (X is also the "dst->path" of A
3919          * in this example).  If X is marked obsolete, "A" will not
3920          * notice.  That's what we are validating here via the
3921          * stale_bundle() check.
3922          *
3923          * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3924          * be marked on it.
3925          * This will force stale_bundle() to fail on any xdst bundle with
3926          * this dst linked in it.
3927          */
3928         if (dst->obsolete < 0 && !stale_bundle(dst))
3929                 return dst;
3930
3931         return NULL;
3932 }
3933
3934 static int stale_bundle(struct dst_entry *dst)
3935 {
3936         return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3937 }
3938
3939 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3940 {
3941         while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3942                 dst->dev = blackhole_netdev;
3943                 dev_hold(dst->dev);
3944                 dev_put(dev);
3945         }
3946 }
3947 EXPORT_SYMBOL(xfrm_dst_ifdown);
3948
3949 static void xfrm_link_failure(struct sk_buff *skb)
3950 {
3951         /* Impossible. Such dst must be popped before reaches point of failure. */
3952 }
3953
3954 static void xfrm_negative_advice(struct sock *sk, struct dst_entry *dst)
3955 {
3956         if (dst->obsolete)
3957                 sk_dst_reset(sk);
3958 }
3959
3960 static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3961 {
3962         while (nr--) {
3963                 struct xfrm_dst *xdst = bundle[nr];
3964                 u32 pmtu, route_mtu_cached;
3965                 struct dst_entry *dst;
3966
3967                 dst = &xdst->u.dst;
3968                 pmtu = dst_mtu(xfrm_dst_child(dst));
3969                 xdst->child_mtu_cached = pmtu;
3970
3971                 pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3972
3973                 route_mtu_cached = dst_mtu(xdst->route);
3974                 xdst->route_mtu_cached = route_mtu_cached;
3975
3976                 if (pmtu > route_mtu_cached)
3977                         pmtu = route_mtu_cached;
3978
3979                 dst_metric_set(dst, RTAX_MTU, pmtu);
3980         }
3981 }
3982
3983 /* Check that the bundle accepts the flow and its components are
3984  * still valid.
3985  */
3986
3987 static int xfrm_bundle_ok(struct xfrm_dst *first)
3988 {
3989         struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3990         struct dst_entry *dst = &first->u.dst;
3991         struct xfrm_dst *xdst;
3992         int start_from, nr;
3993         u32 mtu;
3994
3995         if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3996             (dst->dev && !netif_running(dst->dev)))
3997                 return 0;
3998
3999         if (dst->flags & DST_XFRM_QUEUE)
4000                 return 1;
4001
4002         start_from = nr = 0;
4003         do {
4004                 struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
4005
4006                 if (dst->xfrm->km.state != XFRM_STATE_VALID)
4007                         return 0;
4008                 if (xdst->xfrm_genid != dst->xfrm->genid)
4009                         return 0;
4010                 if (xdst->num_pols > 0 &&
4011                     xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
4012                         return 0;
4013
4014                 bundle[nr++] = xdst;
4015
4016                 mtu = dst_mtu(xfrm_dst_child(dst));
4017                 if (xdst->child_mtu_cached != mtu) {
4018                         start_from = nr;
4019                         xdst->child_mtu_cached = mtu;
4020                 }
4021
4022                 if (!dst_check(xdst->route, xdst->route_cookie))
4023                         return 0;
4024                 mtu = dst_mtu(xdst->route);
4025                 if (xdst->route_mtu_cached != mtu) {
4026                         start_from = nr;
4027                         xdst->route_mtu_cached = mtu;
4028                 }
4029
4030                 dst = xfrm_dst_child(dst);
4031         } while (dst->xfrm);
4032
4033         if (likely(!start_from))
4034                 return 1;
4035
4036         xdst = bundle[start_from - 1];
4037         mtu = xdst->child_mtu_cached;
4038         while (start_from--) {
4039                 dst = &xdst->u.dst;
4040
4041                 mtu = xfrm_state_mtu(dst->xfrm, mtu);
4042                 if (mtu > xdst->route_mtu_cached)
4043                         mtu = xdst->route_mtu_cached;
4044                 dst_metric_set(dst, RTAX_MTU, mtu);
4045                 if (!start_from)
4046                         break;
4047
4048                 xdst = bundle[start_from - 1];
4049                 xdst->child_mtu_cached = mtu;
4050         }
4051
4052         return 1;
4053 }
4054
4055 static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
4056 {
4057         return dst_metric_advmss(xfrm_dst_path(dst));
4058 }
4059
4060 static unsigned int xfrm_mtu(const struct dst_entry *dst)
4061 {
4062         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
4063
4064         return mtu ? : dst_mtu(xfrm_dst_path(dst));
4065 }
4066
4067 static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
4068                                         const void *daddr)
4069 {
4070         while (dst->xfrm) {
4071                 const struct xfrm_state *xfrm = dst->xfrm;
4072
4073                 dst = xfrm_dst_child(dst);
4074
4075                 if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
4076                         continue;
4077                 if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
4078                         daddr = xfrm->coaddr;
4079                 else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
4080                         daddr = &xfrm->id.daddr;
4081         }
4082         return daddr;
4083 }
4084
4085 static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
4086                                            struct sk_buff *skb,
4087                                            const void *daddr)
4088 {
4089         const struct dst_entry *path = xfrm_dst_path(dst);
4090
4091         if (!skb)
4092                 daddr = xfrm_get_dst_nexthop(dst, daddr);
4093         return path->ops->neigh_lookup(path, skb, daddr);
4094 }
4095
4096 static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
4097 {
4098         const struct dst_entry *path = xfrm_dst_path(dst);
4099
4100         daddr = xfrm_get_dst_nexthop(dst, daddr);
4101         path->ops->confirm_neigh(path, daddr);
4102 }
4103
4104 int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
4105 {
4106         int err = 0;
4107
4108         if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
4109                 return -EAFNOSUPPORT;
4110
4111         spin_lock(&xfrm_policy_afinfo_lock);
4112         if (unlikely(xfrm_policy_afinfo[family] != NULL))
4113                 err = -EEXIST;
4114         else {
4115                 struct dst_ops *dst_ops = afinfo->dst_ops;
4116                 if (likely(dst_ops->kmem_cachep == NULL))
4117                         dst_ops->kmem_cachep = xfrm_dst_cache;
4118                 if (likely(dst_ops->check == NULL))
4119                         dst_ops->check = xfrm_dst_check;
4120                 if (likely(dst_ops->default_advmss == NULL))
4121                         dst_ops->default_advmss = xfrm_default_advmss;
4122                 if (likely(dst_ops->mtu == NULL))
4123                         dst_ops->mtu = xfrm_mtu;
4124                 if (likely(dst_ops->negative_advice == NULL))
4125                         dst_ops->negative_advice = xfrm_negative_advice;
4126                 if (likely(dst_ops->link_failure == NULL))
4127                         dst_ops->link_failure = xfrm_link_failure;
4128                 if (likely(dst_ops->neigh_lookup == NULL))
4129                         dst_ops->neigh_lookup = xfrm_neigh_lookup;
4130                 if (likely(!dst_ops->confirm_neigh))
4131                         dst_ops->confirm_neigh = xfrm_confirm_neigh;
4132                 rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
4133         }
4134         spin_unlock(&xfrm_policy_afinfo_lock);
4135
4136         return err;
4137 }
4138 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
4139
4140 void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
4141 {
4142         struct dst_ops *dst_ops = afinfo->dst_ops;
4143         int i;
4144
4145         for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
4146                 if (xfrm_policy_afinfo[i] != afinfo)
4147                         continue;
4148                 RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
4149                 break;
4150         }
4151
4152         synchronize_rcu();
4153
4154         dst_ops->kmem_cachep = NULL;
4155         dst_ops->check = NULL;
4156         dst_ops->negative_advice = NULL;
4157         dst_ops->link_failure = NULL;
4158 }
4159 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
4160
4161 void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
4162 {
4163         spin_lock(&xfrm_if_cb_lock);
4164         rcu_assign_pointer(xfrm_if_cb, ifcb);
4165         spin_unlock(&xfrm_if_cb_lock);
4166 }
4167 EXPORT_SYMBOL(xfrm_if_register_cb);
4168
4169 void xfrm_if_unregister_cb(void)
4170 {
4171         RCU_INIT_POINTER(xfrm_if_cb, NULL);
4172         synchronize_rcu();
4173 }
4174 EXPORT_SYMBOL(xfrm_if_unregister_cb);
4175
4176 #ifdef CONFIG_XFRM_STATISTICS
4177 static int __net_init xfrm_statistics_init(struct net *net)
4178 {
4179         int rv;
4180         net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
4181         if (!net->mib.xfrm_statistics)
4182                 return -ENOMEM;
4183         rv = xfrm_proc_init(net);
4184         if (rv < 0)
4185                 free_percpu(net->mib.xfrm_statistics);
4186         return rv;
4187 }
4188
4189 static void xfrm_statistics_fini(struct net *net)
4190 {
4191         xfrm_proc_fini(net);
4192         free_percpu(net->mib.xfrm_statistics);
4193 }
4194 #else
4195 static int __net_init xfrm_statistics_init(struct net *net)
4196 {
4197         return 0;
4198 }
4199
4200 static void xfrm_statistics_fini(struct net *net)
4201 {
4202 }
4203 #endif
4204
4205 static int __net_init xfrm_policy_init(struct net *net)
4206 {
4207         unsigned int hmask, sz;
4208         int dir, err;
4209
4210         if (net_eq(net, &init_net)) {
4211                 xfrm_dst_cache = KMEM_CACHE(xfrm_dst, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
4212                 err = rhashtable_init(&xfrm_policy_inexact_table,
4213                                       &xfrm_pol_inexact_params);
4214                 BUG_ON(err);
4215         }
4216
4217         hmask = 8 - 1;
4218         sz = (hmask+1) * sizeof(struct hlist_head);
4219
4220         net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4221         if (!net->xfrm.policy_byidx)
4222                 goto out_byidx;
4223         net->xfrm.policy_idx_hmask = hmask;
4224
4225         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4226                 struct xfrm_policy_hash *htab;
4227
4228                 net->xfrm.policy_count[dir] = 0;
4229                 net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4230
4231                 htab = &net->xfrm.policy_bydst[dir];
4232                 htab->table = xfrm_hash_alloc(sz);
4233                 if (!htab->table)
4234                         goto out_bydst;
4235                 htab->hmask = hmask;
4236                 htab->dbits4 = 32;
4237                 htab->sbits4 = 32;
4238                 htab->dbits6 = 128;
4239                 htab->sbits6 = 128;
4240         }
4241         net->xfrm.policy_hthresh.lbits4 = 32;
4242         net->xfrm.policy_hthresh.rbits4 = 32;
4243         net->xfrm.policy_hthresh.lbits6 = 128;
4244         net->xfrm.policy_hthresh.rbits6 = 128;
4245
4246         seqlock_init(&net->xfrm.policy_hthresh.lock);
4247
4248         INIT_LIST_HEAD(&net->xfrm.policy_all);
4249         INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4250         INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4251         INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4252         return 0;
4253
4254 out_bydst:
4255         for (dir--; dir >= 0; dir--) {
4256                 struct xfrm_policy_hash *htab;
4257
4258                 htab = &net->xfrm.policy_bydst[dir];
4259                 xfrm_hash_free(htab->table, sz);
4260         }
4261         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4262 out_byidx:
4263         return -ENOMEM;
4264 }
4265
4266 static void xfrm_policy_fini(struct net *net)
4267 {
4268         struct xfrm_pol_inexact_bin *b, *t;
4269         unsigned int sz;
4270         int dir;
4271
4272         flush_work(&net->xfrm.policy_hash_work);
4273 #ifdef CONFIG_XFRM_SUB_POLICY
4274         xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4275 #endif
4276         xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4277
4278         WARN_ON(!list_empty(&net->xfrm.policy_all));
4279
4280         for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4281                 struct xfrm_policy_hash *htab;
4282
4283                 htab = &net->xfrm.policy_bydst[dir];
4284                 sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4285                 WARN_ON(!hlist_empty(htab->table));
4286                 xfrm_hash_free(htab->table, sz);
4287         }
4288
4289         sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4290         WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4291         xfrm_hash_free(net->xfrm.policy_byidx, sz);
4292
4293         spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4294         list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4295                 __xfrm_policy_inexact_prune_bin(b, true);
4296         spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4297 }
4298
4299 static int __net_init xfrm_net_init(struct net *net)
4300 {
4301         int rv;
4302
4303         /* Initialize the per-net locks here */
4304         spin_lock_init(&net->xfrm.xfrm_state_lock);
4305         spin_lock_init(&net->xfrm.xfrm_policy_lock);
4306         seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4307         mutex_init(&net->xfrm.xfrm_cfg_mutex);
4308         net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4309         net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4310         net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4311
4312         rv = xfrm_statistics_init(net);
4313         if (rv < 0)
4314                 goto out_statistics;
4315         rv = xfrm_state_init(net);
4316         if (rv < 0)
4317                 goto out_state;
4318         rv = xfrm_policy_init(net);
4319         if (rv < 0)
4320                 goto out_policy;
4321         rv = xfrm_sysctl_init(net);
4322         if (rv < 0)
4323                 goto out_sysctl;
4324
4325         rv = xfrm_nat_keepalive_net_init(net);
4326         if (rv < 0)
4327                 goto out_nat_keepalive;
4328
4329         return 0;
4330
4331 out_nat_keepalive:
4332         xfrm_sysctl_fini(net);
4333 out_sysctl:
4334         xfrm_policy_fini(net);
4335 out_policy:
4336         xfrm_state_fini(net);
4337 out_state:
4338         xfrm_statistics_fini(net);
4339 out_statistics:
4340         return rv;
4341 }
4342
4343 static void __net_exit xfrm_net_exit(struct net *net)
4344 {
4345         xfrm_nat_keepalive_net_fini(net);
4346         xfrm_sysctl_fini(net);
4347         xfrm_policy_fini(net);
4348         xfrm_state_fini(net);
4349         xfrm_statistics_fini(net);
4350 }
4351
4352 static struct pernet_operations __net_initdata xfrm_net_ops = {
4353         .init = xfrm_net_init,
4354         .exit = xfrm_net_exit,
4355 };
4356
4357 static const struct flow_dissector_key xfrm_flow_dissector_keys[] = {
4358         {
4359                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
4360                 .offset = offsetof(struct xfrm_flow_keys, control),
4361         },
4362         {
4363                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
4364                 .offset = offsetof(struct xfrm_flow_keys, basic),
4365         },
4366         {
4367                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
4368                 .offset = offsetof(struct xfrm_flow_keys, addrs.ipv4),
4369         },
4370         {
4371                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
4372                 .offset = offsetof(struct xfrm_flow_keys, addrs.ipv6),
4373         },
4374         {
4375                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
4376                 .offset = offsetof(struct xfrm_flow_keys, ports),
4377         },
4378         {
4379                 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
4380                 .offset = offsetof(struct xfrm_flow_keys, gre),
4381         },
4382         {
4383                 .key_id = FLOW_DISSECTOR_KEY_IP,
4384                 .offset = offsetof(struct xfrm_flow_keys, ip),
4385         },
4386         {
4387                 .key_id = FLOW_DISSECTOR_KEY_ICMP,
4388                 .offset = offsetof(struct xfrm_flow_keys, icmp),
4389         },
4390 };
4391
4392 void __init xfrm_init(void)
4393 {
4394         skb_flow_dissector_init(&xfrm_session_dissector,
4395                                 xfrm_flow_dissector_keys,
4396                                 ARRAY_SIZE(xfrm_flow_dissector_keys));
4397
4398         register_pernet_subsys(&xfrm_net_ops);
4399         xfrm_dev_init();
4400         xfrm_input_init();
4401
4402 #ifdef CONFIG_XFRM_ESPINTCP
4403         espintcp_init();
4404 #endif
4405
4406         register_xfrm_state_bpf();
4407         xfrm_nat_keepalive_init(AF_INET);
4408 }
4409
4410 #ifdef CONFIG_AUDITSYSCALL
4411 static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4412                                          struct audit_buffer *audit_buf)
4413 {
4414         struct xfrm_sec_ctx *ctx = xp->security;
4415         struct xfrm_selector *sel = &xp->selector;
4416
4417         if (ctx)
4418                 audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4419                                  ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4420
4421         switch (sel->family) {
4422         case AF_INET:
4423                 audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4424                 if (sel->prefixlen_s != 32)
4425                         audit_log_format(audit_buf, " src_prefixlen=%d",
4426                                          sel->prefixlen_s);
4427                 audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4428                 if (sel->prefixlen_d != 32)
4429                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4430                                          sel->prefixlen_d);
4431                 break;
4432         case AF_INET6:
4433                 audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4434                 if (sel->prefixlen_s != 128)
4435                         audit_log_format(audit_buf, " src_prefixlen=%d",
4436                                          sel->prefixlen_s);
4437                 audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4438                 if (sel->prefixlen_d != 128)
4439                         audit_log_format(audit_buf, " dst_prefixlen=%d",
4440                                          sel->prefixlen_d);
4441                 break;
4442         }
4443 }
4444
4445 void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4446 {
4447         struct audit_buffer *audit_buf;
4448
4449         audit_buf = xfrm_audit_start("SPD-add");
4450         if (audit_buf == NULL)
4451                 return;
4452         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4453         audit_log_format(audit_buf, " res=%u", result);
4454         xfrm_audit_common_policyinfo(xp, audit_buf);
4455         audit_log_end(audit_buf);
4456 }
4457 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4458
4459 void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4460                               bool task_valid)
4461 {
4462         struct audit_buffer *audit_buf;
4463
4464         audit_buf = xfrm_audit_start("SPD-delete");
4465         if (audit_buf == NULL)
4466                 return;
4467         xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4468         audit_log_format(audit_buf, " res=%u", result);
4469         xfrm_audit_common_policyinfo(xp, audit_buf);
4470         audit_log_end(audit_buf);
4471 }
4472 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4473 #endif
4474
4475 #ifdef CONFIG_XFRM_MIGRATE
4476 static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4477                                                     u8 dir, u8 type, struct net *net, u32 if_id)
4478 {
4479         struct xfrm_policy *pol;
4480         struct flowi fl;
4481
4482         memset(&fl, 0, sizeof(fl));
4483
4484         fl.flowi_proto = sel->proto;
4485
4486         switch (sel->family) {
4487         case AF_INET:
4488                 fl.u.ip4.saddr = sel->saddr.a4;
4489                 fl.u.ip4.daddr = sel->daddr.a4;
4490                 if (sel->proto == IPSEC_ULPROTO_ANY)
4491                         break;
4492                 fl.u.flowi4_oif = sel->ifindex;
4493                 fl.u.ip4.fl4_sport = sel->sport;
4494                 fl.u.ip4.fl4_dport = sel->dport;
4495                 break;
4496         case AF_INET6:
4497                 fl.u.ip6.saddr = sel->saddr.in6;
4498                 fl.u.ip6.daddr = sel->daddr.in6;
4499                 if (sel->proto == IPSEC_ULPROTO_ANY)
4500                         break;
4501                 fl.u.flowi6_oif = sel->ifindex;
4502                 fl.u.ip6.fl4_sport = sel->sport;
4503                 fl.u.ip6.fl4_dport = sel->dport;
4504                 break;
4505         default:
4506                 return ERR_PTR(-EAFNOSUPPORT);
4507         }
4508
4509         rcu_read_lock();
4510
4511         pol = xfrm_policy_lookup_bytype(net, type, &fl, sel->family, dir, if_id);
4512         if (IS_ERR_OR_NULL(pol))
4513                 goto out_unlock;
4514
4515         if (!xfrm_pol_hold_rcu(pol))
4516                 pol = NULL;
4517 out_unlock:
4518         rcu_read_unlock();
4519         return pol;
4520 }
4521
4522 static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4523 {
4524         int match = 0;
4525
4526         if (t->mode == m->mode && t->id.proto == m->proto &&
4527             (m->reqid == 0 || t->reqid == m->reqid)) {
4528                 switch (t->mode) {
4529                 case XFRM_MODE_TUNNEL:
4530                 case XFRM_MODE_BEET:
4531                 case XFRM_MODE_IPTFS:
4532                         if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4533                                             m->old_family) &&
4534                             xfrm_addr_equal(&t->saddr, &m->old_saddr,
4535                                             m->old_family)) {
4536                                 match = 1;
4537                         }
4538                         break;
4539                 case XFRM_MODE_TRANSPORT:
4540                         /* in case of transport mode, template does not store
4541                            any IP addresses, hence we just compare mode and
4542                            protocol */
4543                         match = 1;
4544                         break;
4545                 default:
4546                         break;
4547                 }
4548         }
4549         return match;
4550 }
4551
4552 /* update endpoint address(es) of template(s) */
4553 static int xfrm_policy_migrate(struct xfrm_policy *pol,
4554                                struct xfrm_migrate *m, int num_migrate,
4555                                struct netlink_ext_ack *extack)
4556 {
4557         struct xfrm_migrate *mp;
4558         int i, j, n = 0;
4559
4560         write_lock_bh(&pol->lock);
4561         if (unlikely(pol->walk.dead)) {
4562                 /* target policy has been deleted */
4563                 NL_SET_ERR_MSG(extack, "Target policy not found");
4564                 write_unlock_bh(&pol->lock);
4565                 return -ENOENT;
4566         }
4567
4568         for (i = 0; i < pol->xfrm_nr; i++) {
4569                 for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4570                         if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4571                                 continue;
4572                         n++;
4573                         if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4574                             pol->xfrm_vec[i].mode != XFRM_MODE_BEET &&
4575                             pol->xfrm_vec[i].mode != XFRM_MODE_IPTFS)
4576                                 continue;
4577                         /* update endpoints */
4578                         memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4579                                sizeof(pol->xfrm_vec[i].id.daddr));
4580                         memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4581                                sizeof(pol->xfrm_vec[i].saddr));
4582                         pol->xfrm_vec[i].encap_family = mp->new_family;
4583                         /* flush bundles */
4584                         atomic_inc(&pol->genid);
4585                 }
4586         }
4587
4588         write_unlock_bh(&pol->lock);
4589
4590         if (!n)
4591                 return -ENODATA;
4592
4593         return 0;
4594 }
4595
4596 static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
4597                               struct netlink_ext_ack *extack)
4598 {
4599         int i, j;
4600
4601         if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
4602                 NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
4603                 return -EINVAL;
4604         }
4605
4606         for (i = 0; i < num_migrate; i++) {
4607                 if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4608                     xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
4609                         NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
4610                         return -EINVAL;
4611                 }
4612
4613                 /* check if there is any duplicated entry */
4614                 for (j = i + 1; j < num_migrate; j++) {
4615                         if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4616                                     sizeof(m[i].old_daddr)) &&
4617                             !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4618                                     sizeof(m[i].old_saddr)) &&
4619                             m[i].proto == m[j].proto &&
4620                             m[i].mode == m[j].mode &&
4621                             m[i].reqid == m[j].reqid &&
4622                             m[i].old_family == m[j].old_family) {
4623                                 NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
4624                                 return -EINVAL;
4625                         }
4626                 }
4627         }
4628
4629         return 0;
4630 }
4631
4632 int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4633                  struct xfrm_migrate *m, int num_migrate,
4634                  struct xfrm_kmaddress *k, struct net *net,
4635                  struct xfrm_encap_tmpl *encap, u32 if_id,
4636                  struct netlink_ext_ack *extack, struct xfrm_user_offload *xuo)
4637 {
4638         int i, err, nx_cur = 0, nx_new = 0;
4639         struct xfrm_policy *pol = NULL;
4640         struct xfrm_state *x, *xc;
4641         struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4642         struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4643         struct xfrm_migrate *mp;
4644
4645         /* Stage 0 - sanity checks */
4646         err = xfrm_migrate_check(m, num_migrate, extack);
4647         if (err < 0)
4648                 goto out;
4649
4650         if (dir >= XFRM_POLICY_MAX) {
4651                 NL_SET_ERR_MSG(extack, "Invalid policy direction");
4652                 err = -EINVAL;
4653                 goto out;
4654         }
4655
4656         /* Stage 1 - find policy */
4657         pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
4658         if (IS_ERR_OR_NULL(pol)) {
4659                 NL_SET_ERR_MSG(extack, "Target policy not found");
4660                 err = IS_ERR(pol) ? PTR_ERR(pol) : -ENOENT;
4661                 goto out;
4662         }
4663
4664         /* Stage 2 - find and update state(s) */
4665         for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4666                 if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4667                         x_cur[nx_cur] = x;
4668                         nx_cur++;
4669                         xc = xfrm_state_migrate(x, mp, encap, net, xuo, extack);
4670                         if (xc) {
4671                                 x_new[nx_new] = xc;
4672                                 nx_new++;
4673                         } else {
4674                                 err = -ENODATA;
4675                                 goto restore_state;
4676                         }
4677                 }
4678         }
4679
4680         /* Stage 3 - update policy */
4681         err = xfrm_policy_migrate(pol, m, num_migrate, extack);
4682         if (err < 0)
4683                 goto restore_state;
4684
4685         /* Stage 4 - delete old state(s) */
4686         if (nx_cur) {
4687                 xfrm_states_put(x_cur, nx_cur);
4688                 xfrm_states_delete(x_cur, nx_cur);
4689         }
4690
4691         /* Stage 5 - announce */
4692         km_migrate(sel, dir, type, m, num_migrate, k, encap);
4693
4694         xfrm_pol_put(pol);
4695
4696         return 0;
4697 out:
4698         return err;
4699
4700 restore_state:
4701         if (pol)
4702                 xfrm_pol_put(pol);
4703         if (nx_cur)
4704                 xfrm_states_put(x_cur, nx_cur);
4705         if (nx_new)
4706                 xfrm_states_delete(x_new, nx_new);
4707
4708         return err;
4709 }
4710 EXPORT_SYMBOL(xfrm_migrate);
4711 #endif