linux/net/xfrm/xfrm_policy.c
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   1/*
   2 * xfrm_policy.c
   3 *
   4 * Changes:
   5 *      Mitsuru KANDA @USAGI
   6 *      Kazunori MIYAZAWA @USAGI
   7 *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   8 *              IPv6 support
   9 *      Kazunori MIYAZAWA @USAGI
  10 *      YOSHIFUJI Hideaki
  11 *              Split up af-specific portion
  12 *      Derek Atkins <derek@ihtfp.com>          Add the post_input processor
  13 *
  14 */
  15
  16#include <linux/err.h>
  17#include <linux/slab.h>
  18#include <linux/kmod.h>
  19#include <linux/list.h>
  20#include <linux/spinlock.h>
  21#include <linux/workqueue.h>
  22#include <linux/notifier.h>
  23#include <linux/netdevice.h>
  24#include <linux/netfilter.h>
  25#include <linux/module.h>
  26#include <linux/cache.h>
  27#include <linux/audit.h>
  28#include <net/dst.h>
  29#include <net/flow.h>
  30#include <net/xfrm.h>
  31#include <net/ip.h>
  32#ifdef CONFIG_XFRM_STATISTICS
  33#include <net/snmp.h>
  34#endif
  35
  36#include "xfrm_hash.h"
  37
  38DEFINE_MUTEX(xfrm_cfg_mutex);
  39EXPORT_SYMBOL(xfrm_cfg_mutex);
  40
  41static DEFINE_SPINLOCK(xfrm_policy_sk_bundle_lock);
  42static struct dst_entry *xfrm_policy_sk_bundles;
  43static DEFINE_RWLOCK(xfrm_policy_lock);
  44
  45static DEFINE_RWLOCK(xfrm_policy_afinfo_lock);
  46static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO];
  47
  48static struct kmem_cache *xfrm_dst_cache __read_mostly;
  49
  50static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
  51static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
  52static void xfrm_init_pmtu(struct dst_entry *dst);
  53static int stale_bundle(struct dst_entry *dst);
  54static int xfrm_bundle_ok(struct xfrm_dst *xdst);
  55
  56
  57static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
  58                                                int dir);
  59
  60static inline bool
  61__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  62{
  63        const struct flowi4 *fl4 = &fl->u.ip4;
  64
  65        return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
  66                addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
  67                !((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
  68                !((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
  69                (fl4->flowi4_proto == sel->proto || !sel->proto) &&
  70                (fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
  71}
  72
  73static inline bool
  74__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
  75{
  76        const struct flowi6 *fl6 = &fl->u.ip6;
  77
  78        return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
  79                addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
  80                !((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
  81                !((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
  82                (fl6->flowi6_proto == sel->proto || !sel->proto) &&
  83                (fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
  84}
  85
  86bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
  87                         unsigned short family)
  88{
  89        switch (family) {
  90        case AF_INET:
  91                return __xfrm4_selector_match(sel, fl);
  92        case AF_INET6:
  93                return __xfrm6_selector_match(sel, fl);
  94        }
  95        return false;
  96}
  97
  98static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
  99                                                  const xfrm_address_t *saddr,
 100                                                  const xfrm_address_t *daddr,
 101                                                  int family)
 102{
 103        struct xfrm_policy_afinfo *afinfo;
 104        struct dst_entry *dst;
 105
 106        afinfo = xfrm_policy_get_afinfo(family);
 107        if (unlikely(afinfo == NULL))
 108                return ERR_PTR(-EAFNOSUPPORT);
 109
 110        dst = afinfo->dst_lookup(net, tos, saddr, daddr);
 111
 112        xfrm_policy_put_afinfo(afinfo);
 113
 114        return dst;
 115}
 116
 117static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
 118                                                xfrm_address_t *prev_saddr,
 119                                                xfrm_address_t *prev_daddr,
 120                                                int family)
 121{
 122        struct net *net = xs_net(x);
 123        xfrm_address_t *saddr = &x->props.saddr;
 124        xfrm_address_t *daddr = &x->id.daddr;
 125        struct dst_entry *dst;
 126
 127        if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 128                saddr = x->coaddr;
 129                daddr = prev_daddr;
 130        }
 131        if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 132                saddr = prev_saddr;
 133                daddr = x->coaddr;
 134        }
 135
 136        dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
 137
 138        if (!IS_ERR(dst)) {
 139                if (prev_saddr != saddr)
 140                        memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 141                if (prev_daddr != daddr)
 142                        memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 143        }
 144
 145        return dst;
 146}
 147
 148static inline unsigned long make_jiffies(long secs)
 149{
 150        if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 151                return MAX_SCHEDULE_TIMEOUT-1;
 152        else
 153                return secs*HZ;
 154}
 155
 156static void xfrm_policy_timer(unsigned long data)
 157{
 158        struct xfrm_policy *xp = (struct xfrm_policy*)data;
 159        unsigned long now = get_seconds();
 160        long next = LONG_MAX;
 161        int warn = 0;
 162        int dir;
 163
 164        read_lock(&xp->lock);
 165
 166        if (unlikely(xp->walk.dead))
 167                goto out;
 168
 169        dir = xfrm_policy_id2dir(xp->index);
 170
 171        if (xp->lft.hard_add_expires_seconds) {
 172                long tmo = xp->lft.hard_add_expires_seconds +
 173                        xp->curlft.add_time - now;
 174                if (tmo <= 0)
 175                        goto expired;
 176                if (tmo < next)
 177                        next = tmo;
 178        }
 179        if (xp->lft.hard_use_expires_seconds) {
 180                long tmo = xp->lft.hard_use_expires_seconds +
 181                        (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 182                if (tmo <= 0)
 183                        goto expired;
 184                if (tmo < next)
 185                        next = tmo;
 186        }
 187        if (xp->lft.soft_add_expires_seconds) {
 188                long tmo = xp->lft.soft_add_expires_seconds +
 189                        xp->curlft.add_time - now;
 190                if (tmo <= 0) {
 191                        warn = 1;
 192                        tmo = XFRM_KM_TIMEOUT;
 193                }
 194                if (tmo < next)
 195                        next = tmo;
 196        }
 197        if (xp->lft.soft_use_expires_seconds) {
 198                long tmo = xp->lft.soft_use_expires_seconds +
 199                        (xp->curlft.use_time ? : xp->curlft.add_time) - now;
 200                if (tmo <= 0) {
 201                        warn = 1;
 202                        tmo = XFRM_KM_TIMEOUT;
 203                }
 204                if (tmo < next)
 205                        next = tmo;
 206        }
 207
 208        if (warn)
 209                km_policy_expired(xp, dir, 0, 0);
 210        if (next != LONG_MAX &&
 211            !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 212                xfrm_pol_hold(xp);
 213
 214out:
 215        read_unlock(&xp->lock);
 216        xfrm_pol_put(xp);
 217        return;
 218
 219expired:
 220        read_unlock(&xp->lock);
 221        if (!xfrm_policy_delete(xp, dir))
 222                km_policy_expired(xp, dir, 1, 0);
 223        xfrm_pol_put(xp);
 224}
 225
 226static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
 227{
 228        struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 229
 230        if (unlikely(pol->walk.dead))
 231                flo = NULL;
 232        else
 233                xfrm_pol_hold(pol);
 234
 235        return flo;
 236}
 237
 238static int xfrm_policy_flo_check(struct flow_cache_object *flo)
 239{
 240        struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
 241
 242        return !pol->walk.dead;
 243}
 244
 245static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
 246{
 247        xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
 248}
 249
 250static const struct flow_cache_ops xfrm_policy_fc_ops = {
 251        .get = xfrm_policy_flo_get,
 252        .check = xfrm_policy_flo_check,
 253        .delete = xfrm_policy_flo_delete,
 254};
 255
 256/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 257 * SPD calls.
 258 */
 259
 260struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 261{
 262        struct xfrm_policy *policy;
 263
 264        policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 265
 266        if (policy) {
 267                write_pnet(&policy->xp_net, net);
 268                INIT_LIST_HEAD(&policy->walk.all);
 269                INIT_HLIST_NODE(&policy->bydst);
 270                INIT_HLIST_NODE(&policy->byidx);
 271                rwlock_init(&policy->lock);
 272                atomic_set(&policy->refcnt, 1);
 273                setup_timer(&policy->timer, xfrm_policy_timer,
 274                                (unsigned long)policy);
 275                policy->flo.ops = &xfrm_policy_fc_ops;
 276        }
 277        return policy;
 278}
 279EXPORT_SYMBOL(xfrm_policy_alloc);
 280
 281/* Destroy xfrm_policy: descendant resources must be released to this moment. */
 282
 283void xfrm_policy_destroy(struct xfrm_policy *policy)
 284{
 285        BUG_ON(!policy->walk.dead);
 286
 287        if (del_timer(&policy->timer))
 288                BUG();
 289
 290        security_xfrm_policy_free(policy->security);
 291        kfree(policy);
 292}
 293EXPORT_SYMBOL(xfrm_policy_destroy);
 294
 295/* Rule must be locked. Release descentant resources, announce
 296 * entry dead. The rule must be unlinked from lists to the moment.
 297 */
 298
 299static void xfrm_policy_kill(struct xfrm_policy *policy)
 300{
 301        policy->walk.dead = 1;
 302
 303        atomic_inc(&policy->genid);
 304
 305        if (del_timer(&policy->timer))
 306                xfrm_pol_put(policy);
 307
 308        xfrm_pol_put(policy);
 309}
 310
 311static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 312
 313static inline unsigned int idx_hash(struct net *net, u32 index)
 314{
 315        return __idx_hash(index, net->xfrm.policy_idx_hmask);
 316}
 317
 318static struct hlist_head *policy_hash_bysel(struct net *net,
 319                                            const struct xfrm_selector *sel,
 320                                            unsigned short family, int dir)
 321{
 322        unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 323        unsigned int hash = __sel_hash(sel, family, hmask);
 324
 325        return (hash == hmask + 1 ?
 326                &net->xfrm.policy_inexact[dir] :
 327                net->xfrm.policy_bydst[dir].table + hash);
 328}
 329
 330static struct hlist_head *policy_hash_direct(struct net *net,
 331                                             const xfrm_address_t *daddr,
 332                                             const xfrm_address_t *saddr,
 333                                             unsigned short family, int dir)
 334{
 335        unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 336        unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
 337
 338        return net->xfrm.policy_bydst[dir].table + hash;
 339}
 340
 341static void xfrm_dst_hash_transfer(struct hlist_head *list,
 342                                   struct hlist_head *ndsttable,
 343                                   unsigned int nhashmask)
 344{
 345        struct hlist_node *entry, *tmp, *entry0 = NULL;
 346        struct xfrm_policy *pol;
 347        unsigned int h0 = 0;
 348
 349redo:
 350        hlist_for_each_entry_safe(pol, entry, tmp, list, bydst) {
 351                unsigned int h;
 352
 353                h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 354                                pol->family, nhashmask);
 355                if (!entry0) {
 356                        hlist_del(entry);
 357                        hlist_add_head(&pol->bydst, ndsttable+h);
 358                        h0 = h;
 359                } else {
 360                        if (h != h0)
 361                                continue;
 362                        hlist_del(entry);
 363                        hlist_add_after(entry0, &pol->bydst);
 364                }
 365                entry0 = entry;
 366        }
 367        if (!hlist_empty(list)) {
 368                entry0 = NULL;
 369                goto redo;
 370        }
 371}
 372
 373static void xfrm_idx_hash_transfer(struct hlist_head *list,
 374                                   struct hlist_head *nidxtable,
 375                                   unsigned int nhashmask)
 376{
 377        struct hlist_node *entry, *tmp;
 378        struct xfrm_policy *pol;
 379
 380        hlist_for_each_entry_safe(pol, entry, tmp, list, byidx) {
 381                unsigned int h;
 382
 383                h = __idx_hash(pol->index, nhashmask);
 384                hlist_add_head(&pol->byidx, nidxtable+h);
 385        }
 386}
 387
 388static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 389{
 390        return ((old_hmask + 1) << 1) - 1;
 391}
 392
 393static void xfrm_bydst_resize(struct net *net, int dir)
 394{
 395        unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 396        unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 397        unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 398        struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
 399        struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 400        int i;
 401
 402        if (!ndst)
 403                return;
 404
 405        write_lock_bh(&xfrm_policy_lock);
 406
 407        for (i = hmask; i >= 0; i--)
 408                xfrm_dst_hash_transfer(odst + i, ndst, nhashmask);
 409
 410        net->xfrm.policy_bydst[dir].table = ndst;
 411        net->xfrm.policy_bydst[dir].hmask = nhashmask;
 412
 413        write_unlock_bh(&xfrm_policy_lock);
 414
 415        xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 416}
 417
 418static void xfrm_byidx_resize(struct net *net, int total)
 419{
 420        unsigned int hmask = net->xfrm.policy_idx_hmask;
 421        unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 422        unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 423        struct hlist_head *oidx = net->xfrm.policy_byidx;
 424        struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 425        int i;
 426
 427        if (!nidx)
 428                return;
 429
 430        write_lock_bh(&xfrm_policy_lock);
 431
 432        for (i = hmask; i >= 0; i--)
 433                xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 434
 435        net->xfrm.policy_byidx = nidx;
 436        net->xfrm.policy_idx_hmask = nhashmask;
 437
 438        write_unlock_bh(&xfrm_policy_lock);
 439
 440        xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 441}
 442
 443static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 444{
 445        unsigned int cnt = net->xfrm.policy_count[dir];
 446        unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 447
 448        if (total)
 449                *total += cnt;
 450
 451        if ((hmask + 1) < xfrm_policy_hashmax &&
 452            cnt > hmask)
 453                return 1;
 454
 455        return 0;
 456}
 457
 458static inline int xfrm_byidx_should_resize(struct net *net, int total)
 459{
 460        unsigned int hmask = net->xfrm.policy_idx_hmask;
 461
 462        if ((hmask + 1) < xfrm_policy_hashmax &&
 463            total > hmask)
 464                return 1;
 465
 466        return 0;
 467}
 468
 469void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 470{
 471        read_lock_bh(&xfrm_policy_lock);
 472        si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 473        si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 474        si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 475        si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 476        si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 477        si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 478        si->spdhcnt = net->xfrm.policy_idx_hmask;
 479        si->spdhmcnt = xfrm_policy_hashmax;
 480        read_unlock_bh(&xfrm_policy_lock);
 481}
 482EXPORT_SYMBOL(xfrm_spd_getinfo);
 483
 484static DEFINE_MUTEX(hash_resize_mutex);
 485static void xfrm_hash_resize(struct work_struct *work)
 486{
 487        struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 488        int dir, total;
 489
 490        mutex_lock(&hash_resize_mutex);
 491
 492        total = 0;
 493        for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
 494                if (xfrm_bydst_should_resize(net, dir, &total))
 495                        xfrm_bydst_resize(net, dir);
 496        }
 497        if (xfrm_byidx_should_resize(net, total))
 498                xfrm_byidx_resize(net, total);
 499
 500        mutex_unlock(&hash_resize_mutex);
 501}
 502
 503/* Generate new index... KAME seems to generate them ordered by cost
 504 * of an absolute inpredictability of ordering of rules. This will not pass. */
 505static u32 xfrm_gen_index(struct net *net, int dir)
 506{
 507        static u32 idx_generator;
 508
 509        for (;;) {
 510                struct hlist_node *entry;
 511                struct hlist_head *list;
 512                struct xfrm_policy *p;
 513                u32 idx;
 514                int found;
 515
 516                idx = (idx_generator | dir);
 517                idx_generator += 8;
 518                if (idx == 0)
 519                        idx = 8;
 520                list = net->xfrm.policy_byidx + idx_hash(net, idx);
 521                found = 0;
 522                hlist_for_each_entry(p, entry, list, byidx) {
 523                        if (p->index == idx) {
 524                                found = 1;
 525                                break;
 526                        }
 527                }
 528                if (!found)
 529                        return idx;
 530        }
 531}
 532
 533static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
 534{
 535        u32 *p1 = (u32 *) s1;
 536        u32 *p2 = (u32 *) s2;
 537        int len = sizeof(struct xfrm_selector) / sizeof(u32);
 538        int i;
 539
 540        for (i = 0; i < len; i++) {
 541                if (p1[i] != p2[i])
 542                        return 1;
 543        }
 544
 545        return 0;
 546}
 547
 548int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
 549{
 550        struct net *net = xp_net(policy);
 551        struct xfrm_policy *pol;
 552        struct xfrm_policy *delpol;
 553        struct hlist_head *chain;
 554        struct hlist_node *entry, *newpos;
 555        u32 mark = policy->mark.v & policy->mark.m;
 556
 557        write_lock_bh(&xfrm_policy_lock);
 558        chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
 559        delpol = NULL;
 560        newpos = NULL;
 561        hlist_for_each_entry(pol, entry, chain, bydst) {
 562                if (pol->type == policy->type &&
 563                    !selector_cmp(&pol->selector, &policy->selector) &&
 564                    (mark & pol->mark.m) == pol->mark.v &&
 565                    xfrm_sec_ctx_match(pol->security, policy->security) &&
 566                    !WARN_ON(delpol)) {
 567                        if (excl) {
 568                                write_unlock_bh(&xfrm_policy_lock);
 569                                return -EEXIST;
 570                        }
 571                        delpol = pol;
 572                        if (policy->priority > pol->priority)
 573                                continue;
 574                } else if (policy->priority >= pol->priority) {
 575                        newpos = &pol->bydst;
 576                        continue;
 577                }
 578                if (delpol)
 579                        break;
 580        }
 581        if (newpos)
 582                hlist_add_after(newpos, &policy->bydst);
 583        else
 584                hlist_add_head(&policy->bydst, chain);
 585        xfrm_pol_hold(policy);
 586        net->xfrm.policy_count[dir]++;
 587        atomic_inc(&flow_cache_genid);
 588        rt_genid_bump(net);
 589        if (delpol)
 590                __xfrm_policy_unlink(delpol, dir);
 591        policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir);
 592        hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
 593        policy->curlft.add_time = get_seconds();
 594        policy->curlft.use_time = 0;
 595        if (!mod_timer(&policy->timer, jiffies + HZ))
 596                xfrm_pol_hold(policy);
 597        list_add(&policy->walk.all, &net->xfrm.policy_all);
 598        write_unlock_bh(&xfrm_policy_lock);
 599
 600        if (delpol)
 601                xfrm_policy_kill(delpol);
 602        else if (xfrm_bydst_should_resize(net, dir, NULL))
 603                schedule_work(&net->xfrm.policy_hash_work);
 604
 605        return 0;
 606}
 607EXPORT_SYMBOL(xfrm_policy_insert);
 608
 609struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
 610                                          int dir, struct xfrm_selector *sel,
 611                                          struct xfrm_sec_ctx *ctx, int delete,
 612                                          int *err)
 613{
 614        struct xfrm_policy *pol, *ret;
 615        struct hlist_head *chain;
 616        struct hlist_node *entry;
 617
 618        *err = 0;
 619        write_lock_bh(&xfrm_policy_lock);
 620        chain = policy_hash_bysel(net, sel, sel->family, dir);
 621        ret = NULL;
 622        hlist_for_each_entry(pol, entry, chain, bydst) {
 623                if (pol->type == type &&
 624                    (mark & pol->mark.m) == pol->mark.v &&
 625                    !selector_cmp(sel, &pol->selector) &&
 626                    xfrm_sec_ctx_match(ctx, pol->security)) {
 627                        xfrm_pol_hold(pol);
 628                        if (delete) {
 629                                *err = security_xfrm_policy_delete(
 630                                                                pol->security);
 631                                if (*err) {
 632                                        write_unlock_bh(&xfrm_policy_lock);
 633                                        return pol;
 634                                }
 635                                __xfrm_policy_unlink(pol, dir);
 636                        }
 637                        ret = pol;
 638                        break;
 639                }
 640        }
 641        write_unlock_bh(&xfrm_policy_lock);
 642
 643        if (ret && delete)
 644                xfrm_policy_kill(ret);
 645        return ret;
 646}
 647EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
 648
 649struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
 650                                     int dir, u32 id, int delete, int *err)
 651{
 652        struct xfrm_policy *pol, *ret;
 653        struct hlist_head *chain;
 654        struct hlist_node *entry;
 655
 656        *err = -ENOENT;
 657        if (xfrm_policy_id2dir(id) != dir)
 658                return NULL;
 659
 660        *err = 0;
 661        write_lock_bh(&xfrm_policy_lock);
 662        chain = net->xfrm.policy_byidx + idx_hash(net, id);
 663        ret = NULL;
 664        hlist_for_each_entry(pol, entry, chain, byidx) {
 665                if (pol->type == type && pol->index == id &&
 666                    (mark & pol->mark.m) == pol->mark.v) {
 667                        xfrm_pol_hold(pol);
 668                        if (delete) {
 669                                *err = security_xfrm_policy_delete(
 670                                                                pol->security);
 671                                if (*err) {
 672                                        write_unlock_bh(&xfrm_policy_lock);
 673                                        return pol;
 674                                }
 675                                __xfrm_policy_unlink(pol, dir);
 676                        }
 677                        ret = pol;
 678                        break;
 679                }
 680        }
 681        write_unlock_bh(&xfrm_policy_lock);
 682
 683        if (ret && delete)
 684                xfrm_policy_kill(ret);
 685        return ret;
 686}
 687EXPORT_SYMBOL(xfrm_policy_byid);
 688
 689#ifdef CONFIG_SECURITY_NETWORK_XFRM
 690static inline int
 691xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
 692{
 693        int dir, err = 0;
 694
 695        for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 696                struct xfrm_policy *pol;
 697                struct hlist_node *entry;
 698                int i;
 699
 700                hlist_for_each_entry(pol, entry,
 701                                     &net->xfrm.policy_inexact[dir], bydst) {
 702                        if (pol->type != type)
 703                                continue;
 704                        err = security_xfrm_policy_delete(pol->security);
 705                        if (err) {
 706                                xfrm_audit_policy_delete(pol, 0,
 707                                                         audit_info->loginuid,
 708                                                         audit_info->sessionid,
 709                                                         audit_info->secid);
 710                                return err;
 711                        }
 712                }
 713                for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 714                        hlist_for_each_entry(pol, entry,
 715                                             net->xfrm.policy_bydst[dir].table + i,
 716                                             bydst) {
 717                                if (pol->type != type)
 718                                        continue;
 719                                err = security_xfrm_policy_delete(
 720                                                                pol->security);
 721                                if (err) {
 722                                        xfrm_audit_policy_delete(pol, 0,
 723                                                        audit_info->loginuid,
 724                                                        audit_info->sessionid,
 725                                                        audit_info->secid);
 726                                        return err;
 727                                }
 728                        }
 729                }
 730        }
 731        return err;
 732}
 733#else
 734static inline int
 735xfrm_policy_flush_secctx_check(struct net *net, u8 type, struct xfrm_audit *audit_info)
 736{
 737        return 0;
 738}
 739#endif
 740
 741int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info)
 742{
 743        int dir, err = 0, cnt = 0;
 744
 745        write_lock_bh(&xfrm_policy_lock);
 746
 747        err = xfrm_policy_flush_secctx_check(net, type, audit_info);
 748        if (err)
 749                goto out;
 750
 751        for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 752                struct xfrm_policy *pol;
 753                struct hlist_node *entry;
 754                int i;
 755
 756        again1:
 757                hlist_for_each_entry(pol, entry,
 758                                     &net->xfrm.policy_inexact[dir], bydst) {
 759                        if (pol->type != type)
 760                                continue;
 761                        __xfrm_policy_unlink(pol, dir);
 762                        write_unlock_bh(&xfrm_policy_lock);
 763                        cnt++;
 764
 765                        xfrm_audit_policy_delete(pol, 1, audit_info->loginuid,
 766                                                 audit_info->sessionid,
 767                                                 audit_info->secid);
 768
 769                        xfrm_policy_kill(pol);
 770
 771                        write_lock_bh(&xfrm_policy_lock);
 772                        goto again1;
 773                }
 774
 775                for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
 776        again2:
 777                        hlist_for_each_entry(pol, entry,
 778                                             net->xfrm.policy_bydst[dir].table + i,
 779                                             bydst) {
 780                                if (pol->type != type)
 781                                        continue;
 782                                __xfrm_policy_unlink(pol, dir);
 783                                write_unlock_bh(&xfrm_policy_lock);
 784                                cnt++;
 785
 786                                xfrm_audit_policy_delete(pol, 1,
 787                                                         audit_info->loginuid,
 788                                                         audit_info->sessionid,
 789                                                         audit_info->secid);
 790                                xfrm_policy_kill(pol);
 791
 792                                write_lock_bh(&xfrm_policy_lock);
 793                                goto again2;
 794                        }
 795                }
 796
 797        }
 798        if (!cnt)
 799                err = -ESRCH;
 800out:
 801        write_unlock_bh(&xfrm_policy_lock);
 802        return err;
 803}
 804EXPORT_SYMBOL(xfrm_policy_flush);
 805
 806int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
 807                     int (*func)(struct xfrm_policy *, int, int, void*),
 808                     void *data)
 809{
 810        struct xfrm_policy *pol;
 811        struct xfrm_policy_walk_entry *x;
 812        int error = 0;
 813
 814        if (walk->type >= XFRM_POLICY_TYPE_MAX &&
 815            walk->type != XFRM_POLICY_TYPE_ANY)
 816                return -EINVAL;
 817
 818        if (list_empty(&walk->walk.all) && walk->seq != 0)
 819                return 0;
 820
 821        write_lock_bh(&xfrm_policy_lock);
 822        if (list_empty(&walk->walk.all))
 823                x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
 824        else
 825                x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
 826        list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
 827                if (x->dead)
 828                        continue;
 829                pol = container_of(x, struct xfrm_policy, walk);
 830                if (walk->type != XFRM_POLICY_TYPE_ANY &&
 831                    walk->type != pol->type)
 832                        continue;
 833                error = func(pol, xfrm_policy_id2dir(pol->index),
 834                             walk->seq, data);
 835                if (error) {
 836                        list_move_tail(&walk->walk.all, &x->all);
 837                        goto out;
 838                }
 839                walk->seq++;
 840        }
 841        if (walk->seq == 0) {
 842                error = -ENOENT;
 843                goto out;
 844        }
 845        list_del_init(&walk->walk.all);
 846out:
 847        write_unlock_bh(&xfrm_policy_lock);
 848        return error;
 849}
 850EXPORT_SYMBOL(xfrm_policy_walk);
 851
 852void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
 853{
 854        INIT_LIST_HEAD(&walk->walk.all);
 855        walk->walk.dead = 1;
 856        walk->type = type;
 857        walk->seq = 0;
 858}
 859EXPORT_SYMBOL(xfrm_policy_walk_init);
 860
 861void xfrm_policy_walk_done(struct xfrm_policy_walk *walk)
 862{
 863        if (list_empty(&walk->walk.all))
 864                return;
 865
 866        write_lock_bh(&xfrm_policy_lock);
 867        list_del(&walk->walk.all);
 868        write_unlock_bh(&xfrm_policy_lock);
 869}
 870EXPORT_SYMBOL(xfrm_policy_walk_done);
 871
 872/*
 873 * Find policy to apply to this flow.
 874 *
 875 * Returns 0 if policy found, else an -errno.
 876 */
 877static int xfrm_policy_match(const struct xfrm_policy *pol,
 878                             const struct flowi *fl,
 879                             u8 type, u16 family, int dir)
 880{
 881        const struct xfrm_selector *sel = &pol->selector;
 882        int ret = -ESRCH;
 883        bool match;
 884
 885        if (pol->family != family ||
 886            (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
 887            pol->type != type)
 888                return ret;
 889
 890        match = xfrm_selector_match(sel, fl, family);
 891        if (match)
 892                ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
 893                                                  dir);
 894
 895        return ret;
 896}
 897
 898static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
 899                                                     const struct flowi *fl,
 900                                                     u16 family, u8 dir)
 901{
 902        int err;
 903        struct xfrm_policy *pol, *ret;
 904        const xfrm_address_t *daddr, *saddr;
 905        struct hlist_node *entry;
 906        struct hlist_head *chain;
 907        u32 priority = ~0U;
 908
 909        daddr = xfrm_flowi_daddr(fl, family);
 910        saddr = xfrm_flowi_saddr(fl, family);
 911        if (unlikely(!daddr || !saddr))
 912                return NULL;
 913
 914        read_lock_bh(&xfrm_policy_lock);
 915        chain = policy_hash_direct(net, daddr, saddr, family, dir);
 916        ret = NULL;
 917        hlist_for_each_entry(pol, entry, chain, bydst) {
 918                err = xfrm_policy_match(pol, fl, type, family, dir);
 919                if (err) {
 920                        if (err == -ESRCH)
 921                                continue;
 922                        else {
 923                                ret = ERR_PTR(err);
 924                                goto fail;
 925                        }
 926                } else {
 927                        ret = pol;
 928                        priority = ret->priority;
 929                        break;
 930                }
 931        }
 932        chain = &net->xfrm.policy_inexact[dir];
 933        hlist_for_each_entry(pol, entry, chain, bydst) {
 934                err = xfrm_policy_match(pol, fl, type, family, dir);
 935                if (err) {
 936                        if (err == -ESRCH)
 937                                continue;
 938                        else {
 939                                ret = ERR_PTR(err);
 940                                goto fail;
 941                        }
 942                } else if (pol->priority < priority) {
 943                        ret = pol;
 944                        break;
 945                }
 946        }
 947        if (ret)
 948                xfrm_pol_hold(ret);
 949fail:
 950        read_unlock_bh(&xfrm_policy_lock);
 951
 952        return ret;
 953}
 954
 955static struct xfrm_policy *
 956__xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
 957{
 958#ifdef CONFIG_XFRM_SUB_POLICY
 959        struct xfrm_policy *pol;
 960
 961        pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
 962        if (pol != NULL)
 963                return pol;
 964#endif
 965        return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
 966}
 967
 968static struct flow_cache_object *
 969xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
 970                   u8 dir, struct flow_cache_object *old_obj, void *ctx)
 971{
 972        struct xfrm_policy *pol;
 973
 974        if (old_obj)
 975                xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
 976
 977        pol = __xfrm_policy_lookup(net, fl, family, dir);
 978        if (IS_ERR_OR_NULL(pol))
 979                return ERR_CAST(pol);
 980
 981        /* Resolver returns two references:
 982         * one for cache and one for caller of flow_cache_lookup() */
 983        xfrm_pol_hold(pol);
 984
 985        return &pol->flo;
 986}
 987
 988static inline int policy_to_flow_dir(int dir)
 989{
 990        if (XFRM_POLICY_IN == FLOW_DIR_IN &&
 991            XFRM_POLICY_OUT == FLOW_DIR_OUT &&
 992            XFRM_POLICY_FWD == FLOW_DIR_FWD)
 993                return dir;
 994        switch (dir) {
 995        default:
 996        case XFRM_POLICY_IN:
 997                return FLOW_DIR_IN;
 998        case XFRM_POLICY_OUT:
 999                return FLOW_DIR_OUT;
1000        case XFRM_POLICY_FWD:
1001                return FLOW_DIR_FWD;
1002        }
1003}
1004
1005static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
1006                                                 const struct flowi *fl)
1007{
1008        struct xfrm_policy *pol;
1009
1010        read_lock_bh(&xfrm_policy_lock);
1011        if ((pol = sk->sk_policy[dir]) != NULL) {
1012                bool match = xfrm_selector_match(&pol->selector, fl,
1013                                                 sk->sk_family);
1014                int err = 0;
1015
1016                if (match) {
1017                        if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
1018                                pol = NULL;
1019                                goto out;
1020                        }
1021                        err = security_xfrm_policy_lookup(pol->security,
1022                                                      fl->flowi_secid,
1023                                                      policy_to_flow_dir(dir));
1024                        if (!err)
1025                                xfrm_pol_hold(pol);
1026                        else if (err == -ESRCH)
1027                                pol = NULL;
1028                        else
1029                                pol = ERR_PTR(err);
1030                } else
1031                        pol = NULL;
1032        }
1033out:
1034        read_unlock_bh(&xfrm_policy_lock);
1035        return pol;
1036}
1037
1038static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
1039{
1040        struct net *net = xp_net(pol);
1041        struct hlist_head *chain = policy_hash_bysel(net, &pol->selector,
1042                                                     pol->family, dir);
1043
1044        list_add(&pol->walk.all, &net->xfrm.policy_all);
1045        hlist_add_head(&pol->bydst, chain);
1046        hlist_add_head(&pol->byidx, net->xfrm.policy_byidx+idx_hash(net, pol->index));
1047        net->xfrm.policy_count[dir]++;
1048        xfrm_pol_hold(pol);
1049
1050        if (xfrm_bydst_should_resize(net, dir, NULL))
1051                schedule_work(&net->xfrm.policy_hash_work);
1052}
1053
1054static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
1055                                                int dir)
1056{
1057        struct net *net = xp_net(pol);
1058
1059        if (hlist_unhashed(&pol->bydst))
1060                return NULL;
1061
1062        hlist_del(&pol->bydst);
1063        hlist_del(&pol->byidx);
1064        list_del(&pol->walk.all);
1065        net->xfrm.policy_count[dir]--;
1066
1067        return pol;
1068}
1069
1070int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
1071{
1072        write_lock_bh(&xfrm_policy_lock);
1073        pol = __xfrm_policy_unlink(pol, dir);
1074        write_unlock_bh(&xfrm_policy_lock);
1075        if (pol) {
1076                xfrm_policy_kill(pol);
1077                return 0;
1078        }
1079        return -ENOENT;
1080}
1081EXPORT_SYMBOL(xfrm_policy_delete);
1082
1083int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
1084{
1085        struct net *net = xp_net(pol);
1086        struct xfrm_policy *old_pol;
1087
1088#ifdef CONFIG_XFRM_SUB_POLICY
1089        if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
1090                return -EINVAL;
1091#endif
1092
1093        write_lock_bh(&xfrm_policy_lock);
1094        old_pol = sk->sk_policy[dir];
1095        sk->sk_policy[dir] = pol;
1096        if (pol) {
1097                pol->curlft.add_time = get_seconds();
1098                pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir);
1099                __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir);
1100        }
1101        if (old_pol)
1102                /* Unlinking succeeds always. This is the only function
1103                 * allowed to delete or replace socket policy.
1104                 */
1105                __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir);
1106        write_unlock_bh(&xfrm_policy_lock);
1107
1108        if (old_pol) {
1109                xfrm_policy_kill(old_pol);
1110        }
1111        return 0;
1112}
1113
1114static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
1115{
1116        struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
1117
1118        if (newp) {
1119                newp->selector = old->selector;
1120                if (security_xfrm_policy_clone(old->security,
1121                                               &newp->security)) {
1122                        kfree(newp);
1123                        return NULL;  /* ENOMEM */
1124                }
1125                newp->lft = old->lft;
1126                newp->curlft = old->curlft;
1127                newp->mark = old->mark;
1128                newp->action = old->action;
1129                newp->flags = old->flags;
1130                newp->xfrm_nr = old->xfrm_nr;
1131                newp->index = old->index;
1132                newp->type = old->type;
1133                memcpy(newp->xfrm_vec, old->xfrm_vec,
1134                       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
1135                write_lock_bh(&xfrm_policy_lock);
1136                __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir);
1137                write_unlock_bh(&xfrm_policy_lock);
1138                xfrm_pol_put(newp);
1139        }
1140        return newp;
1141}
1142
1143int __xfrm_sk_clone_policy(struct sock *sk)
1144{
1145        struct xfrm_policy *p0 = sk->sk_policy[0],
1146                           *p1 = sk->sk_policy[1];
1147
1148        sk->sk_policy[0] = sk->sk_policy[1] = NULL;
1149        if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
1150                return -ENOMEM;
1151        if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
1152                return -ENOMEM;
1153        return 0;
1154}
1155
1156static int
1157xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
1158               unsigned short family)
1159{
1160        int err;
1161        struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1162
1163        if (unlikely(afinfo == NULL))
1164                return -EINVAL;
1165        err = afinfo->get_saddr(net, local, remote);
1166        xfrm_policy_put_afinfo(afinfo);
1167        return err;
1168}
1169
1170/* Resolve list of templates for the flow, given policy. */
1171
1172static int
1173xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
1174                      struct xfrm_state **xfrm, unsigned short family)
1175{
1176        struct net *net = xp_net(policy);
1177        int nx;
1178        int i, error;
1179        xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
1180        xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
1181        xfrm_address_t tmp;
1182
1183        for (nx=0, i = 0; i < policy->xfrm_nr; i++) {
1184                struct xfrm_state *x;
1185                xfrm_address_t *remote = daddr;
1186                xfrm_address_t *local  = saddr;
1187                struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
1188
1189                if (tmpl->mode == XFRM_MODE_TUNNEL ||
1190                    tmpl->mode == XFRM_MODE_BEET) {
1191                        remote = &tmpl->id.daddr;
1192                        local = &tmpl->saddr;
1193                        if (xfrm_addr_any(local, tmpl->encap_family)) {
1194                                error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family);
1195                                if (error)
1196                                        goto fail;
1197                                local = &tmp;
1198                        }
1199                }
1200
1201                x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
1202
1203                if (x && x->km.state == XFRM_STATE_VALID) {
1204                        xfrm[nx++] = x;
1205                        daddr = remote;
1206                        saddr = local;
1207                        continue;
1208                }
1209                if (x) {
1210                        error = (x->km.state == XFRM_STATE_ERROR ?
1211                                 -EINVAL : -EAGAIN);
1212                        xfrm_state_put(x);
1213                }
1214                else if (error == -ESRCH)
1215                        error = -EAGAIN;
1216
1217                if (!tmpl->optional)
1218                        goto fail;
1219        }
1220        return nx;
1221
1222fail:
1223        for (nx--; nx>=0; nx--)
1224                xfrm_state_put(xfrm[nx]);
1225        return error;
1226}
1227
1228static int
1229xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
1230                  struct xfrm_state **xfrm, unsigned short family)
1231{
1232        struct xfrm_state *tp[XFRM_MAX_DEPTH];
1233        struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
1234        int cnx = 0;
1235        int error;
1236        int ret;
1237        int i;
1238
1239        for (i = 0; i < npols; i++) {
1240                if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
1241                        error = -ENOBUFS;
1242                        goto fail;
1243                }
1244
1245                ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
1246                if (ret < 0) {
1247                        error = ret;
1248                        goto fail;
1249                } else
1250                        cnx += ret;
1251        }
1252
1253        /* found states are sorted for outbound processing */
1254        if (npols > 1)
1255                xfrm_state_sort(xfrm, tpp, cnx, family);
1256
1257        return cnx;
1258
1259 fail:
1260        for (cnx--; cnx>=0; cnx--)
1261                xfrm_state_put(tpp[cnx]);
1262        return error;
1263
1264}
1265
1266/* Check that the bundle accepts the flow and its components are
1267 * still valid.
1268 */
1269
1270static inline int xfrm_get_tos(const struct flowi *fl, int family)
1271{
1272        struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1273        int tos;
1274
1275        if (!afinfo)
1276                return -EINVAL;
1277
1278        tos = afinfo->get_tos(fl);
1279
1280        xfrm_policy_put_afinfo(afinfo);
1281
1282        return tos;
1283}
1284
1285static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
1286{
1287        struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1288        struct dst_entry *dst = &xdst->u.dst;
1289
1290        if (xdst->route == NULL) {
1291                /* Dummy bundle - if it has xfrms we were not
1292                 * able to build bundle as template resolution failed.
1293                 * It means we need to try again resolving. */
1294                if (xdst->num_xfrms > 0)
1295                        return NULL;
1296        } else {
1297                /* Real bundle */
1298                if (stale_bundle(dst))
1299                        return NULL;
1300        }
1301
1302        dst_hold(dst);
1303        return flo;
1304}
1305
1306static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
1307{
1308        struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1309        struct dst_entry *dst = &xdst->u.dst;
1310
1311        if (!xdst->route)
1312                return 0;
1313        if (stale_bundle(dst))
1314                return 0;
1315
1316        return 1;
1317}
1318
1319static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
1320{
1321        struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
1322        struct dst_entry *dst = &xdst->u.dst;
1323
1324        dst_free(dst);
1325}
1326
1327static const struct flow_cache_ops xfrm_bundle_fc_ops = {
1328        .get = xfrm_bundle_flo_get,
1329        .check = xfrm_bundle_flo_check,
1330        .delete = xfrm_bundle_flo_delete,
1331};
1332
1333static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
1334{
1335        struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1336        struct dst_ops *dst_ops;
1337        struct xfrm_dst *xdst;
1338
1339        if (!afinfo)
1340                return ERR_PTR(-EINVAL);
1341
1342        switch (family) {
1343        case AF_INET:
1344                dst_ops = &net->xfrm.xfrm4_dst_ops;
1345                break;
1346#if IS_ENABLED(CONFIG_IPV6)
1347        case AF_INET6:
1348                dst_ops = &net->xfrm.xfrm6_dst_ops;
1349                break;
1350#endif
1351        default:
1352                BUG();
1353        }
1354        xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
1355
1356        if (likely(xdst)) {
1357                struct dst_entry *dst = &xdst->u.dst;
1358
1359                memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
1360                xdst->flo.ops = &xfrm_bundle_fc_ops;
1361                if (afinfo->init_dst)
1362                        afinfo->init_dst(net, xdst);
1363        } else
1364                xdst = ERR_PTR(-ENOBUFS);
1365
1366        xfrm_policy_put_afinfo(afinfo);
1367
1368        return xdst;
1369}
1370
1371static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
1372                                 int nfheader_len)
1373{
1374        struct xfrm_policy_afinfo *afinfo =
1375                xfrm_policy_get_afinfo(dst->ops->family);
1376        int err;
1377
1378        if (!afinfo)
1379                return -EINVAL;
1380
1381        err = afinfo->init_path(path, dst, nfheader_len);
1382
1383        xfrm_policy_put_afinfo(afinfo);
1384
1385        return err;
1386}
1387
1388static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
1389                                const struct flowi *fl)
1390{
1391        struct xfrm_policy_afinfo *afinfo =
1392                xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
1393        int err;
1394
1395        if (!afinfo)
1396                return -EINVAL;
1397
1398        err = afinfo->fill_dst(xdst, dev, fl);
1399
1400        xfrm_policy_put_afinfo(afinfo);
1401
1402        return err;
1403}
1404
1405
1406/* Allocate chain of dst_entry's, attach known xfrm's, calculate
1407 * all the metrics... Shortly, bundle a bundle.
1408 */
1409
1410static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
1411                                            struct xfrm_state **xfrm, int nx,
1412                                            const struct flowi *fl,
1413                                            struct dst_entry *dst)
1414{
1415        struct net *net = xp_net(policy);
1416        unsigned long now = jiffies;
1417        struct net_device *dev;
1418        struct xfrm_mode *inner_mode;
1419        struct dst_entry *dst_prev = NULL;
1420        struct dst_entry *dst0 = NULL;
1421        int i = 0;
1422        int err;
1423        int header_len = 0;
1424        int nfheader_len = 0;
1425        int trailer_len = 0;
1426        int tos;
1427        int family = policy->selector.family;
1428        xfrm_address_t saddr, daddr;
1429
1430        xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
1431
1432        tos = xfrm_get_tos(fl, family);
1433        err = tos;
1434        if (tos < 0)
1435                goto put_states;
1436
1437        dst_hold(dst);
1438
1439        for (; i < nx; i++) {
1440                struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
1441                struct dst_entry *dst1 = &xdst->u.dst;
1442
1443                err = PTR_ERR(xdst);
1444                if (IS_ERR(xdst)) {
1445                        dst_release(dst);
1446                        goto put_states;
1447                }
1448
1449                if (xfrm[i]->sel.family == AF_UNSPEC) {
1450                        inner_mode = xfrm_ip2inner_mode(xfrm[i],
1451                                                        xfrm_af2proto(family));
1452                        if (!inner_mode) {
1453                                err = -EAFNOSUPPORT;
1454                                dst_release(dst);
1455                                goto put_states;
1456                        }
1457                } else
1458                        inner_mode = xfrm[i]->inner_mode;
1459
1460                if (!dst_prev)
1461                        dst0 = dst1;
1462                else {
1463                        dst_prev->child = dst_clone(dst1);
1464                        dst1->flags |= DST_NOHASH;
1465                }
1466
1467                xdst->route = dst;
1468                dst_copy_metrics(dst1, dst);
1469
1470                if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
1471                        family = xfrm[i]->props.family;
1472                        dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
1473                                              family);
1474                        err = PTR_ERR(dst);
1475                        if (IS_ERR(dst))
1476                                goto put_states;
1477                } else
1478                        dst_hold(dst);
1479
1480                dst1->xfrm = xfrm[i];
1481                xdst->xfrm_genid = xfrm[i]->genid;
1482
1483                dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
1484                dst1->flags |= DST_HOST;
1485                dst1->lastuse = now;
1486
1487                dst1->input = dst_discard;
1488                dst1->output = inner_mode->afinfo->output;
1489
1490                dst1->next = dst_prev;
1491                dst_prev = dst1;
1492
1493                header_len += xfrm[i]->props.header_len;
1494                if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
1495                        nfheader_len += xfrm[i]->props.header_len;
1496                trailer_len += xfrm[i]->props.trailer_len;
1497        }
1498
1499        dst_prev->child = dst;
1500        dst0->path = dst;
1501
1502        err = -ENODEV;
1503        dev = dst->dev;
1504        if (!dev)
1505                goto free_dst;
1506
1507        xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
1508        xfrm_init_pmtu(dst_prev);
1509
1510        for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
1511                struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
1512
1513                err = xfrm_fill_dst(xdst, dev, fl);
1514                if (err)
1515                        goto free_dst;
1516
1517                dst_prev->header_len = header_len;
1518                dst_prev->trailer_len = trailer_len;
1519                header_len -= xdst->u.dst.xfrm->props.header_len;
1520                trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
1521        }
1522
1523out:
1524        return dst0;
1525
1526put_states:
1527        for (; i < nx; i++)
1528                xfrm_state_put(xfrm[i]);
1529free_dst:
1530        if (dst0)
1531                dst_free(dst0);
1532        dst0 = ERR_PTR(err);
1533        goto out;
1534}
1535
1536static int inline
1537xfrm_dst_alloc_copy(void **target, const void *src, int size)
1538{
1539        if (!*target) {
1540                *target = kmalloc(size, GFP_ATOMIC);
1541                if (!*target)
1542                        return -ENOMEM;
1543        }
1544        memcpy(*target, src, size);
1545        return 0;
1546}
1547
1548static int inline
1549xfrm_dst_update_parent(struct dst_entry *dst, const struct xfrm_selector *sel)
1550{
1551#ifdef CONFIG_XFRM_SUB_POLICY
1552        struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1553        return xfrm_dst_alloc_copy((void **)&(xdst->partner),
1554                                   sel, sizeof(*sel));
1555#else
1556        return 0;
1557#endif
1558}
1559
1560static int inline
1561xfrm_dst_update_origin(struct dst_entry *dst, const struct flowi *fl)
1562{
1563#ifdef CONFIG_XFRM_SUB_POLICY
1564        struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
1565        return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
1566#else
1567        return 0;
1568#endif
1569}
1570
1571static int xfrm_expand_policies(const struct flowi *fl, u16 family,
1572                                struct xfrm_policy **pols,
1573                                int *num_pols, int *num_xfrms)
1574{
1575        int i;
1576
1577        if (*num_pols == 0 || !pols[0]) {
1578                *num_pols = 0;
1579                *num_xfrms = 0;
1580                return 0;
1581        }
1582        if (IS_ERR(pols[0]))
1583                return PTR_ERR(pols[0]);
1584
1585        *num_xfrms = pols[0]->xfrm_nr;
1586
1587#ifdef CONFIG_XFRM_SUB_POLICY
1588        if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
1589            pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
1590                pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
1591                                                    XFRM_POLICY_TYPE_MAIN,
1592                                                    fl, family,
1593                                                    XFRM_POLICY_OUT);
1594                if (pols[1]) {
1595                        if (IS_ERR(pols[1])) {
1596                                xfrm_pols_put(pols, *num_pols);
1597                                return PTR_ERR(pols[1]);
1598                        }
1599                        (*num_pols) ++;
1600                        (*num_xfrms) += pols[1]->xfrm_nr;
1601                }
1602        }
1603#endif
1604        for (i = 0; i < *num_pols; i++) {
1605                if (pols[i]->action != XFRM_POLICY_ALLOW) {
1606                        *num_xfrms = -1;
1607                        break;
1608                }
1609        }
1610
1611        return 0;
1612
1613}
1614
1615static struct xfrm_dst *
1616xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
1617                               const struct flowi *fl, u16 family,
1618                               struct dst_entry *dst_orig)
1619{
1620        struct net *net = xp_net(pols[0]);
1621        struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
1622        struct dst_entry *dst;
1623        struct xfrm_dst *xdst;
1624        int err;
1625
1626        /* Try to instantiate a bundle */
1627        err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
1628        if (err <= 0) {
1629                if (err != 0 && err != -EAGAIN)
1630                        XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1631                return ERR_PTR(err);
1632        }
1633
1634        dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
1635        if (IS_ERR(dst)) {
1636                XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
1637                return ERR_CAST(dst);
1638        }
1639
1640        xdst = (struct xfrm_dst *)dst;
1641        xdst->num_xfrms = err;
1642        if (num_pols > 1)
1643                err = xfrm_dst_update_parent(dst, &pols[1]->selector);
1644        else
1645                err = xfrm_dst_update_origin(dst, fl);
1646        if (unlikely(err)) {
1647                dst_free(dst);
1648                XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
1649                return ERR_PTR(err);
1650        }
1651
1652        xdst->num_pols = num_pols;
1653        memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1654        xdst->policy_genid = atomic_read(&pols[0]->genid);
1655
1656        return xdst;
1657}
1658
1659static struct flow_cache_object *
1660xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
1661                   struct flow_cache_object *oldflo, void *ctx)
1662{
1663        struct dst_entry *dst_orig = (struct dst_entry *)ctx;
1664        struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1665        struct xfrm_dst *xdst, *new_xdst;
1666        int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
1667
1668        /* Check if the policies from old bundle are usable */
1669        xdst = NULL;
1670        if (oldflo) {
1671                xdst = container_of(oldflo, struct xfrm_dst, flo);
1672                num_pols = xdst->num_pols;
1673                num_xfrms = xdst->num_xfrms;
1674                pol_dead = 0;
1675                for (i = 0; i < num_pols; i++) {
1676                        pols[i] = xdst->pols[i];
1677                        pol_dead |= pols[i]->walk.dead;
1678                }
1679                if (pol_dead) {
1680                        dst_free(&xdst->u.dst);
1681                        xdst = NULL;
1682                        num_pols = 0;
1683                        num_xfrms = 0;
1684                        oldflo = NULL;
1685                }
1686        }
1687
1688        /* Resolve policies to use if we couldn't get them from
1689         * previous cache entry */
1690        if (xdst == NULL) {
1691                num_pols = 1;
1692                pols[0] = __xfrm_policy_lookup(net, fl, family, dir);
1693                err = xfrm_expand_policies(fl, family, pols,
1694                                           &num_pols, &num_xfrms);
1695                if (err < 0)
1696                        goto inc_error;
1697                if (num_pols == 0)
1698                        return NULL;
1699                if (num_xfrms <= 0)
1700                        goto make_dummy_bundle;
1701        }
1702
1703        new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, dst_orig);
1704        if (IS_ERR(new_xdst)) {
1705                err = PTR_ERR(new_xdst);
1706                if (err != -EAGAIN)
1707                        goto error;
1708                if (oldflo == NULL)
1709                        goto make_dummy_bundle;
1710                dst_hold(&xdst->u.dst);
1711                return oldflo;
1712        } else if (new_xdst == NULL) {
1713                num_xfrms = 0;
1714                if (oldflo == NULL)
1715                        goto make_dummy_bundle;
1716                xdst->num_xfrms = 0;
1717                dst_hold(&xdst->u.dst);
1718                return oldflo;
1719        }
1720
1721        /* Kill the previous bundle */
1722        if (xdst) {
1723                /* The policies were stolen for newly generated bundle */
1724                xdst->num_pols = 0;
1725                dst_free(&xdst->u.dst);
1726        }
1727
1728        /* Flow cache does not have reference, it dst_free()'s,
1729         * but we do need to return one reference for original caller */
1730        dst_hold(&new_xdst->u.dst);
1731        return &new_xdst->flo;
1732
1733make_dummy_bundle:
1734        /* We found policies, but there's no bundles to instantiate:
1735         * either because the policy blocks, has no transformations or
1736         * we could not build template (no xfrm_states).*/
1737        xdst = xfrm_alloc_dst(net, family);
1738        if (IS_ERR(xdst)) {
1739                xfrm_pols_put(pols, num_pols);
1740                return ERR_CAST(xdst);
1741        }
1742        xdst->num_pols = num_pols;
1743        xdst->num_xfrms = num_xfrms;
1744        memcpy(xdst->pols, pols, sizeof(struct xfrm_policy*) * num_pols);
1745
1746        dst_hold(&xdst->u.dst);
1747        return &xdst->flo;
1748
1749inc_error:
1750        XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
1751error:
1752        if (xdst != NULL)
1753                dst_free(&xdst->u.dst);
1754        else
1755                xfrm_pols_put(pols, num_pols);
1756        return ERR_PTR(err);
1757}
1758
1759static struct dst_entry *make_blackhole(struct net *net, u16 family,
1760                                        struct dst_entry *dst_orig)
1761{
1762        struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
1763        struct dst_entry *ret;
1764
1765        if (!afinfo) {
1766                dst_release(dst_orig);
1767                return ERR_PTR(-EINVAL);
1768        } else {
1769                ret = afinfo->blackhole_route(net, dst_orig);
1770        }
1771        xfrm_policy_put_afinfo(afinfo);
1772
1773        return ret;
1774}
1775
1776/* Main function: finds/creates a bundle for given flow.
1777 *
1778 * At the moment we eat a raw IP route. Mostly to speed up lookups
1779 * on interfaces with disabled IPsec.
1780 */
1781struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
1782                              const struct flowi *fl,
1783                              struct sock *sk, int flags)
1784{
1785        struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
1786        struct flow_cache_object *flo;
1787        struct xfrm_dst *xdst;
1788        struct dst_entry *dst, *route;
1789        u16 family = dst_orig->ops->family;
1790        u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
1791        int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
1792
1793restart:
1794        dst = NULL;
1795        xdst = NULL;
1796        route = NULL;
1797
1798        if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
1799                num_pols = 1;
1800                pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
1801                err = xfrm_expand_policies(fl, family, pols,
1802                                           &num_pols, &num_xfrms);
1803                if (err < 0)
1804                        goto dropdst;
1805
1806                if (num_pols) {
1807                        if (num_xfrms <= 0) {
1808                                drop_pols = num_pols;
1809                                goto no_transform;
1810                        }
1811
1812                        xdst = xfrm_resolve_and_create_bundle(
1813                                        pols, num_pols, fl,
1814                                        family, dst_orig);
1815                        if (IS_ERR(xdst)) {
1816                                xfrm_pols_put(pols, num_pols);
1817                                err = PTR_ERR(xdst);
1818                                goto dropdst;
1819                        } else if (xdst == NULL) {
1820                                num_xfrms = 0;
1821                                drop_pols = num_pols;
1822                                goto no_transform;
1823                        }
1824
1825                        dst_hold(&xdst->u.dst);
1826
1827                        spin_lock_bh(&xfrm_policy_sk_bundle_lock);
1828                        xdst->u.dst.next = xfrm_policy_sk_bundles;
1829                        xfrm_policy_sk_bundles = &xdst->u.dst;
1830                        spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
1831
1832                        route = xdst->route;
1833                }
1834        }
1835
1836        if (xdst == NULL) {
1837                /* To accelerate a bit...  */
1838                if ((dst_orig->flags & DST_NOXFRM) ||
1839                    !net->xfrm.policy_count[XFRM_POLICY_OUT])
1840                        goto nopol;
1841
1842                flo = flow_cache_lookup(net, fl, family, dir,
1843                                        xfrm_bundle_lookup, dst_orig);
1844                if (flo == NULL)
1845                        goto nopol;
1846                if (IS_ERR(flo)) {
1847                        err = PTR_ERR(flo);
1848                        goto dropdst;
1849                }
1850                xdst = container_of(flo, struct xfrm_dst, flo);
1851
1852                num_pols = xdst->num_pols;
1853                num_xfrms = xdst->num_xfrms;
1854                memcpy(pols, xdst->pols, sizeof(struct xfrm_policy*) * num_pols);
1855                route = xdst->route;
1856        }
1857
1858        dst = &xdst->u.dst;
1859        if (route == NULL && num_xfrms > 0) {
1860                /* The only case when xfrm_bundle_lookup() returns a
1861                 * bundle with null route, is when the template could
1862                 * not be resolved. It means policies are there, but
1863                 * bundle could not be created, since we don't yet
1864                 * have the xfrm_state's. We need to wait for KM to
1865                 * negotiate new SA's or bail out with error.*/
1866                if (net->xfrm.sysctl_larval_drop) {
1867                        /* EREMOTE tells the caller to generate
1868                         * a one-shot blackhole route. */
1869                        dst_release(dst);
1870                        xfrm_pols_put(pols, drop_pols);
1871                        XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1872
1873                        return make_blackhole(net, family, dst_orig);
1874                }
1875                if (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP) {
1876                        DECLARE_WAITQUEUE(wait, current);
1877
1878                        add_wait_queue(&net->xfrm.km_waitq, &wait);
1879                        set_current_state(TASK_INTERRUPTIBLE);
1880                        schedule();
1881                        set_current_state(TASK_RUNNING);
1882                        remove_wait_queue(&net->xfrm.km_waitq, &wait);
1883
1884                        if (!signal_pending(current)) {
1885                                dst_release(dst);
1886                                goto restart;
1887                        }
1888
1889                        err = -ERESTART;
1890                } else
1891                        err = -EAGAIN;
1892
1893                XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
1894                goto error;
1895        }
1896
1897no_transform:
1898        if (num_pols == 0)
1899                goto nopol;
1900
1901        if ((flags & XFRM_LOOKUP_ICMP) &&
1902            !(pols[0]->flags & XFRM_POLICY_ICMP)) {
1903                err = -ENOENT;
1904                goto error;
1905        }
1906
1907        for (i = 0; i < num_pols; i++)
1908                pols[i]->curlft.use_time = get_seconds();
1909
1910        if (num_xfrms < 0) {
1911                /* Prohibit the flow */
1912                XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
1913                err = -EPERM;
1914                goto error;
1915        } else if (num_xfrms > 0) {
1916                /* Flow transformed */
1917                dst_release(dst_orig);
1918        } else {
1919                /* Flow passes untransformed */
1920                dst_release(dst);
1921                dst = dst_orig;
1922        }
1923ok:
1924        xfrm_pols_put(pols, drop_pols);
1925        if (dst && dst->xfrm &&
1926            dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
1927                dst->flags |= DST_XFRM_TUNNEL;
1928        return dst;
1929
1930nopol:
1931        if (!(flags & XFRM_LOOKUP_ICMP)) {
1932                dst = dst_orig;
1933                goto ok;
1934        }
1935        err = -ENOENT;
1936error:
1937        dst_release(dst);
1938dropdst:
1939        dst_release(dst_orig);
1940        xfrm_pols_put(pols, drop_pols);
1941        return ERR_PTR(err);
1942}
1943EXPORT_SYMBOL(xfrm_lookup);
1944
1945static inline int
1946xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
1947{
1948        struct xfrm_state *x;
1949
1950        if (!skb->sp || idx < 0 || idx >= skb->sp->len)
1951                return 0;
1952        x = skb->sp->xvec[idx];
1953        if (!x->type->reject)
1954                return 0;
1955        return x->type->reject(x, skb, fl);
1956}
1957
1958/* When skb is transformed back to its "native" form, we have to
1959 * check policy restrictions. At the moment we make this in maximally
1960 * stupid way. Shame on me. :-) Of course, connected sockets must
1961 * have policy cached at them.
1962 */
1963
1964static inline int
1965xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
1966              unsigned short family)
1967{
1968        if (xfrm_state_kern(x))
1969                return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
1970        return  x->id.proto == tmpl->id.proto &&
1971                (x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
1972                (x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
1973                x->props.mode == tmpl->mode &&
1974                (tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
1975                 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
1976                !(x->props.mode != XFRM_MODE_TRANSPORT &&
1977                  xfrm_state_addr_cmp(tmpl, x, family));
1978}
1979
1980/*
1981 * 0 or more than 0 is returned when validation is succeeded (either bypass
1982 * because of optional transport mode, or next index of the mathced secpath
1983 * state with the template.
1984 * -1 is returned when no matching template is found.
1985 * Otherwise "-2 - errored_index" is returned.
1986 */
1987static inline int
1988xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
1989               unsigned short family)
1990{
1991        int idx = start;
1992
1993        if (tmpl->optional) {
1994                if (tmpl->mode == XFRM_MODE_TRANSPORT)
1995                        return start;
1996        } else
1997                start = -1;
1998        for (; idx < sp->len; idx++) {
1999                if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
2000                        return ++idx;
2001                if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
2002                        if (start == -1)
2003                                start = -2-idx;
2004                        break;
2005                }
2006        }
2007        return start;
2008}
2009
2010int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
2011                          unsigned int family, int reverse)
2012{
2013        struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2014        int err;
2015
2016        if (unlikely(afinfo == NULL))
2017                return -EAFNOSUPPORT;
2018
2019        afinfo->decode_session(skb, fl, reverse);
2020        err = security_xfrm_decode_session(skb, &fl->flowi_secid);
2021        xfrm_policy_put_afinfo(afinfo);
2022        return err;
2023}
2024EXPORT_SYMBOL(__xfrm_decode_session);
2025
2026static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
2027{
2028        for (; k < sp->len; k++) {
2029                if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
2030                        *idxp = k;
2031                        return 1;
2032                }
2033        }
2034
2035        return 0;
2036}
2037
2038int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
2039                        unsigned short family)
2040{
2041        struct net *net = dev_net(skb->dev);
2042        struct xfrm_policy *pol;
2043        struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2044        int npols = 0;
2045        int xfrm_nr;
2046        int pi;
2047        int reverse;
2048        struct flowi fl;
2049        u8 fl_dir;
2050        int xerr_idx = -1;
2051
2052        reverse = dir & ~XFRM_POLICY_MASK;
2053        dir &= XFRM_POLICY_MASK;
2054        fl_dir = policy_to_flow_dir(dir);
2055
2056        if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
2057                XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
2058                return 0;
2059        }
2060
2061        nf_nat_decode_session(skb, &fl, family);
2062
2063        /* First, check used SA against their selectors. */
2064        if (skb->sp) {
2065                int i;
2066
2067                for (i=skb->sp->len-1; i>=0; i--) {
2068                        struct xfrm_state *x = skb->sp->xvec[i];
2069                        if (!xfrm_selector_match(&x->sel, &fl, family)) {
2070                                XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
2071                                return 0;
2072                        }
2073                }
2074        }
2075
2076        pol = NULL;
2077        if (sk && sk->sk_policy[dir]) {
2078                pol = xfrm_sk_policy_lookup(sk, dir, &fl);
2079                if (IS_ERR(pol)) {
2080                        XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2081                        return 0;
2082                }
2083        }
2084
2085        if (!pol) {
2086                struct flow_cache_object *flo;
2087
2088                flo = flow_cache_lookup(net, &fl, family, fl_dir,
2089                                        xfrm_policy_lookup, NULL);
2090                if (IS_ERR_OR_NULL(flo))
2091                        pol = ERR_CAST(flo);
2092                else
2093                        pol = container_of(flo, struct xfrm_policy, flo);
2094        }
2095
2096        if (IS_ERR(pol)) {
2097                XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2098                return 0;
2099        }
2100
2101        if (!pol) {
2102                if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
2103                        xfrm_secpath_reject(xerr_idx, skb, &fl);
2104                        XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
2105                        return 0;
2106                }
2107                return 1;
2108        }
2109
2110        pol->curlft.use_time = get_seconds();
2111
2112        pols[0] = pol;
2113        npols ++;
2114#ifdef CONFIG_XFRM_SUB_POLICY
2115        if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2116                pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
2117                                                    &fl, family,
2118                                                    XFRM_POLICY_IN);
2119                if (pols[1]) {
2120                        if (IS_ERR(pols[1])) {
2121                                XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
2122                                return 0;
2123                        }
2124                        pols[1]->curlft.use_time = get_seconds();
2125                        npols ++;
2126                }
2127        }
2128#endif
2129
2130        if (pol->action == XFRM_POLICY_ALLOW) {
2131                struct sec_path *sp;
2132                static struct sec_path dummy;
2133                struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
2134                struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
2135                struct xfrm_tmpl **tpp = tp;
2136                int ti = 0;
2137                int i, k;
2138
2139                if ((sp = skb->sp) == NULL)
2140                        sp = &dummy;
2141
2142                for (pi = 0; pi < npols; pi++) {
2143                        if (pols[pi] != pol &&
2144                            pols[pi]->action != XFRM_POLICY_ALLOW) {
2145                                XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2146                                goto reject;
2147                        }
2148                        if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
2149                                XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
2150                                goto reject_error;
2151                        }
2152                        for (i = 0; i < pols[pi]->xfrm_nr; i++)
2153                                tpp[ti++] = &pols[pi]->xfrm_vec[i];
2154                }
2155                xfrm_nr = ti;
2156                if (npols > 1) {
2157                        xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
2158                        tpp = stp;
2159                }
2160
2161                /* For each tunnel xfrm, find the first matching tmpl.
2162                 * For each tmpl before that, find corresponding xfrm.
2163                 * Order is _important_. Later we will implement
2164                 * some barriers, but at the moment barriers
2165                 * are implied between each two transformations.
2166                 */
2167                for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
2168                        k = xfrm_policy_ok(tpp[i], sp, k, family);
2169                        if (k < 0) {
2170                                if (k < -1)
2171                                        /* "-2 - errored_index" returned */
2172                                        xerr_idx = -(2+k);
2173                                XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2174                                goto reject;
2175                        }
2176                }
2177
2178                if (secpath_has_nontransport(sp, k, &xerr_idx)) {
2179                        XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
2180                        goto reject;
2181                }
2182
2183                xfrm_pols_put(pols, npols);
2184                return 1;
2185        }
2186        XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
2187
2188reject:
2189        xfrm_secpath_reject(xerr_idx, skb, &fl);
2190reject_error:
2191        xfrm_pols_put(pols, npols);
2192        return 0;
2193}
2194EXPORT_SYMBOL(__xfrm_policy_check);
2195
2196int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
2197{
2198        struct net *net = dev_net(skb->dev);
2199        struct flowi fl;
2200        struct dst_entry *dst;
2201        int res = 1;
2202
2203        if (xfrm_decode_session(skb, &fl, family) < 0) {
2204                XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
2205                return 0;
2206        }
2207
2208        skb_dst_force(skb);
2209
2210        dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, 0);
2211        if (IS_ERR(dst)) {
2212                res = 0;
2213                dst = NULL;
2214        }
2215        skb_dst_set(skb, dst);
2216        return res;
2217}
2218EXPORT_SYMBOL(__xfrm_route_forward);
2219
2220/* Optimize later using cookies and generation ids. */
2221
2222static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
2223{
2224        /* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
2225         * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
2226         * get validated by dst_ops->check on every use.  We do this
2227         * because when a normal route referenced by an XFRM dst is
2228         * obsoleted we do not go looking around for all parent
2229         * referencing XFRM dsts so that we can invalidate them.  It
2230         * is just too much work.  Instead we make the checks here on
2231         * every use.  For example:
2232         *
2233         *      XFRM dst A --> IPv4 dst X
2234         *
2235         * X is the "xdst->route" of A (X is also the "dst->path" of A
2236         * in this example).  If X is marked obsolete, "A" will not
2237         * notice.  That's what we are validating here via the
2238         * stale_bundle() check.
2239         *
2240         * When a policy's bundle is pruned, we dst_free() the XFRM
2241         * dst which causes it's ->obsolete field to be set to
2242         * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
2243         * this, we want to force a new route lookup.
2244         */
2245        if (dst->obsolete < 0 && !stale_bundle(dst))
2246                return dst;
2247
2248        return NULL;
2249}
2250
2251static int stale_bundle(struct dst_entry *dst)
2252{
2253        return !xfrm_bundle_ok((struct xfrm_dst *)dst);
2254}
2255
2256void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
2257{
2258        while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
2259                dst->dev = dev_net(dev)->loopback_dev;
2260                dev_hold(dst->dev);
2261                dev_put(dev);
2262        }
2263}
2264EXPORT_SYMBOL(xfrm_dst_ifdown);
2265
2266static void xfrm_link_failure(struct sk_buff *skb)
2267{
2268        /* Impossible. Such dst must be popped before reaches point of failure. */
2269}
2270
2271static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
2272{
2273        if (dst) {
2274                if (dst->obsolete) {
2275                        dst_release(dst);
2276                        dst = NULL;
2277                }
2278        }
2279        return dst;
2280}
2281
2282static void __xfrm_garbage_collect(struct net *net)
2283{
2284        struct dst_entry *head, *next;
2285
2286        spin_lock_bh(&xfrm_policy_sk_bundle_lock);
2287        head = xfrm_policy_sk_bundles;
2288        xfrm_policy_sk_bundles = NULL;
2289        spin_unlock_bh(&xfrm_policy_sk_bundle_lock);
2290
2291        while (head) {
2292                next = head->next;
2293                dst_free(head);
2294                head = next;
2295        }
2296}
2297
2298static void xfrm_garbage_collect(struct net *net)
2299{
2300        flow_cache_flush();
2301        __xfrm_garbage_collect(net);
2302}
2303
2304static void xfrm_garbage_collect_deferred(struct net *net)
2305{
2306        flow_cache_flush_deferred();
2307        __xfrm_garbage_collect(net);
2308}
2309
2310static void xfrm_init_pmtu(struct dst_entry *dst)
2311{
2312        do {
2313                struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2314                u32 pmtu, route_mtu_cached;
2315
2316                pmtu = dst_mtu(dst->child);
2317                xdst->child_mtu_cached = pmtu;
2318
2319                pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
2320
2321                route_mtu_cached = dst_mtu(xdst->route);
2322                xdst->route_mtu_cached = route_mtu_cached;
2323
2324                if (pmtu > route_mtu_cached)
2325                        pmtu = route_mtu_cached;
2326
2327                dst_metric_set(dst, RTAX_MTU, pmtu);
2328        } while ((dst = dst->next));
2329}
2330
2331/* Check that the bundle accepts the flow and its components are
2332 * still valid.
2333 */
2334
2335static int xfrm_bundle_ok(struct xfrm_dst *first)
2336{
2337        struct dst_entry *dst = &first->u.dst;
2338        struct xfrm_dst *last;
2339        u32 mtu;
2340
2341        if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
2342            (dst->dev && !netif_running(dst->dev)))
2343                return 0;
2344
2345        last = NULL;
2346
2347        do {
2348                struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
2349
2350                if (dst->xfrm->km.state != XFRM_STATE_VALID)
2351                        return 0;
2352                if (xdst->xfrm_genid != dst->xfrm->genid)
2353                        return 0;
2354                if (xdst->num_pols > 0 &&
2355                    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
2356                        return 0;
2357
2358                mtu = dst_mtu(dst->child);
2359                if (xdst->child_mtu_cached != mtu) {
2360                        last = xdst;
2361                        xdst->child_mtu_cached = mtu;
2362                }
2363
2364                if (!dst_check(xdst->route, xdst->route_cookie))
2365                        return 0;
2366                mtu = dst_mtu(xdst->route);
2367                if (xdst->route_mtu_cached != mtu) {
2368                        last = xdst;
2369                        xdst->route_mtu_cached = mtu;
2370                }
2371
2372                dst = dst->child;
2373        } while (dst->xfrm);
2374
2375        if (likely(!last))
2376                return 1;
2377
2378        mtu = last->child_mtu_cached;
2379        for (;;) {
2380                dst = &last->u.dst;
2381
2382                mtu = xfrm_state_mtu(dst->xfrm, mtu);
2383                if (mtu > last->route_mtu_cached)
2384                        mtu = last->route_mtu_cached;
2385                dst_metric_set(dst, RTAX_MTU, mtu);
2386
2387                if (last == first)
2388                        break;
2389
2390                last = (struct xfrm_dst *)last->u.dst.next;
2391                last->child_mtu_cached = mtu;
2392        }
2393
2394        return 1;
2395}
2396
2397static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
2398{
2399        return dst_metric_advmss(dst->path);
2400}
2401
2402static unsigned int xfrm_mtu(const struct dst_entry *dst)
2403{
2404        unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2405
2406        return mtu ? : dst_mtu(dst->path);
2407}
2408
2409static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
2410                                           struct sk_buff *skb,
2411                                           const void *daddr)
2412{
2413        return dst->path->ops->neigh_lookup(dst, skb, daddr);
2414}
2415
2416int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
2417{
2418        struct net *net;
2419        int err = 0;
2420        if (unlikely(afinfo == NULL))
2421                return -EINVAL;
2422        if (unlikely(afinfo->family >= NPROTO))
2423                return -EAFNOSUPPORT;
2424        write_lock_bh(&xfrm_policy_afinfo_lock);
2425        if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
2426                err = -ENOBUFS;
2427        else {
2428                struct dst_ops *dst_ops = afinfo->dst_ops;
2429                if (likely(dst_ops->kmem_cachep == NULL))
2430                        dst_ops->kmem_cachep = xfrm_dst_cache;
2431                if (likely(dst_ops->check == NULL))
2432                        dst_ops->check = xfrm_dst_check;
2433                if (likely(dst_ops->default_advmss == NULL))
2434                        dst_ops->default_advmss = xfrm_default_advmss;
2435                if (likely(dst_ops->mtu == NULL))
2436                        dst_ops->mtu = xfrm_mtu;
2437                if (likely(dst_ops->negative_advice == NULL))
2438                        dst_ops->negative_advice = xfrm_negative_advice;
2439                if (likely(dst_ops->link_failure == NULL))
2440                        dst_ops->link_failure = xfrm_link_failure;
2441                if (likely(dst_ops->neigh_lookup == NULL))
2442                        dst_ops->neigh_lookup = xfrm_neigh_lookup;
2443                if (likely(afinfo->garbage_collect == NULL))
2444                        afinfo->garbage_collect = xfrm_garbage_collect_deferred;
2445                xfrm_policy_afinfo[afinfo->family] = afinfo;
2446        }
2447        write_unlock_bh(&xfrm_policy_afinfo_lock);
2448
2449        rtnl_lock();
2450        for_each_net(net) {
2451                struct dst_ops *xfrm_dst_ops;
2452
2453                switch (afinfo->family) {
2454                case AF_INET:
2455                        xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
2456                        break;
2457#if IS_ENABLED(CONFIG_IPV6)
2458                case AF_INET6:
2459                        xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
2460                        break;
2461#endif
2462                default:
2463                        BUG();
2464                }
2465                *xfrm_dst_ops = *afinfo->dst_ops;
2466        }
2467        rtnl_unlock();
2468
2469        return err;
2470}
2471EXPORT_SYMBOL(xfrm_policy_register_afinfo);
2472
2473int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
2474{
2475        int err = 0;
2476        if (unlikely(afinfo == NULL))
2477                return -EINVAL;
2478        if (unlikely(afinfo->family >= NPROTO))
2479                return -EAFNOSUPPORT;
2480        write_lock_bh(&xfrm_policy_afinfo_lock);
2481        if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
2482                if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
2483                        err = -EINVAL;
2484                else {
2485                        struct dst_ops *dst_ops = afinfo->dst_ops;
2486                        xfrm_policy_afinfo[afinfo->family] = NULL;
2487                        dst_ops->kmem_cachep = NULL;
2488                        dst_ops->check = NULL;
2489                        dst_ops->negative_advice = NULL;
2490                        dst_ops->link_failure = NULL;
2491                        afinfo->garbage_collect = NULL;
2492                }
2493        }
2494        write_unlock_bh(&xfrm_policy_afinfo_lock);
2495        return err;
2496}
2497EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
2498
2499static void __net_init xfrm_dst_ops_init(struct net *net)
2500{
2501        struct xfrm_policy_afinfo *afinfo;
2502
2503        read_lock_bh(&xfrm_policy_afinfo_lock);
2504        afinfo = xfrm_policy_afinfo[AF_INET];
2505        if (afinfo)
2506                net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
2507#if IS_ENABLED(CONFIG_IPV6)
2508        afinfo = xfrm_policy_afinfo[AF_INET6];
2509        if (afinfo)
2510                net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
2511#endif
2512        read_unlock_bh(&xfrm_policy_afinfo_lock);
2513}
2514
2515static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
2516{
2517        struct xfrm_policy_afinfo *afinfo;
2518        if (unlikely(family >= NPROTO))
2519                return NULL;
2520        read_lock(&xfrm_policy_afinfo_lock);
2521        afinfo = xfrm_policy_afinfo[family];
2522        if (unlikely(!afinfo))
2523                read_unlock(&xfrm_policy_afinfo_lock);
2524        return afinfo;
2525}
2526
2527static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
2528{
2529        read_unlock(&xfrm_policy_afinfo_lock);
2530}
2531
2532static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
2533{
2534        struct net_device *dev = ptr;
2535
2536        switch (event) {
2537        case NETDEV_DOWN:
2538                xfrm_garbage_collect(dev_net(dev));
2539        }
2540        return NOTIFY_DONE;
2541}
2542
2543static struct notifier_block xfrm_dev_notifier = {
2544        .notifier_call  = xfrm_dev_event,
2545};
2546
2547#ifdef CONFIG_XFRM_STATISTICS
2548static int __net_init xfrm_statistics_init(struct net *net)
2549{
2550        int rv;
2551
2552        if (snmp_mib_init((void __percpu **)net->mib.xfrm_statistics,
2553                          sizeof(struct linux_xfrm_mib),
2554                          __alignof__(struct linux_xfrm_mib)) < 0)
2555                return -ENOMEM;
2556        rv = xfrm_proc_init(net);
2557        if (rv < 0)
2558                snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2559        return rv;
2560}
2561
2562static void xfrm_statistics_fini(struct net *net)
2563{
2564        xfrm_proc_fini(net);
2565        snmp_mib_free((void __percpu **)net->mib.xfrm_statistics);
2566}
2567#else
2568static int __net_init xfrm_statistics_init(struct net *net)
2569{
2570        return 0;
2571}
2572
2573static void xfrm_statistics_fini(struct net *net)
2574{
2575}
2576#endif
2577
2578static int __net_init xfrm_policy_init(struct net *net)
2579{
2580        unsigned int hmask, sz;
2581        int dir;
2582
2583        if (net_eq(net, &init_net))
2584                xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
2585                                           sizeof(struct xfrm_dst),
2586                                           0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
2587                                           NULL);
2588
2589        hmask = 8 - 1;
2590        sz = (hmask+1) * sizeof(struct hlist_head);
2591
2592        net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
2593        if (!net->xfrm.policy_byidx)
2594                goto out_byidx;
2595        net->xfrm.policy_idx_hmask = hmask;
2596
2597        for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2598                struct xfrm_policy_hash *htab;
2599
2600                net->xfrm.policy_count[dir] = 0;
2601                INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
2602
2603                htab = &net->xfrm.policy_bydst[dir];
2604                htab->table = xfrm_hash_alloc(sz);
2605                if (!htab->table)
2606                        goto out_bydst;
2607                htab->hmask = hmask;
2608        }
2609
2610        INIT_LIST_HEAD(&net->xfrm.policy_all);
2611        INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
2612        if (net_eq(net, &init_net))
2613                register_netdevice_notifier(&xfrm_dev_notifier);
2614        return 0;
2615
2616out_bydst:
2617        for (dir--; dir >= 0; dir--) {
2618                struct xfrm_policy_hash *htab;
2619
2620                htab = &net->xfrm.policy_bydst[dir];
2621                xfrm_hash_free(htab->table, sz);
2622        }
2623        xfrm_hash_free(net->xfrm.policy_byidx, sz);
2624out_byidx:
2625        return -ENOMEM;
2626}
2627
2628static void xfrm_policy_fini(struct net *net)
2629{
2630        struct xfrm_audit audit_info;
2631        unsigned int sz;
2632        int dir;
2633
2634        flush_work(&net->xfrm.policy_hash_work);
2635#ifdef CONFIG_XFRM_SUB_POLICY
2636        audit_info.loginuid = -1;
2637        audit_info.sessionid = -1;
2638        audit_info.secid = 0;
2639        xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, &audit_info);
2640#endif
2641        audit_info.loginuid = -1;
2642        audit_info.sessionid = -1;
2643        audit_info.secid = 0;
2644        xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, &audit_info);
2645
2646        WARN_ON(!list_empty(&net->xfrm.policy_all));
2647
2648        for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
2649                struct xfrm_policy_hash *htab;
2650
2651                WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
2652
2653                htab = &net->xfrm.policy_bydst[dir];
2654                sz = (htab->hmask + 1);
2655                WARN_ON(!hlist_empty(htab->table));
2656                xfrm_hash_free(htab->table, sz);
2657        }
2658
2659        sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
2660        WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
2661        xfrm_hash_free(net->xfrm.policy_byidx, sz);
2662}
2663
2664static int __net_init xfrm_net_init(struct net *net)
2665{
2666        int rv;
2667
2668        rv = xfrm_statistics_init(net);
2669        if (rv < 0)
2670                goto out_statistics;
2671        rv = xfrm_state_init(net);
2672        if (rv < 0)
2673                goto out_state;
2674        rv = xfrm_policy_init(net);
2675        if (rv < 0)
2676                goto out_policy;
2677        xfrm_dst_ops_init(net);
2678        rv = xfrm_sysctl_init(net);
2679        if (rv < 0)
2680                goto out_sysctl;
2681        return 0;
2682
2683out_sysctl:
2684        xfrm_policy_fini(net);
2685out_policy:
2686        xfrm_state_fini(net);
2687out_state:
2688        xfrm_statistics_fini(net);
2689out_statistics:
2690        return rv;
2691}
2692
2693static void __net_exit xfrm_net_exit(struct net *net)
2694{
2695        xfrm_sysctl_fini(net);
2696        xfrm_policy_fini(net);
2697        xfrm_state_fini(net);
2698        xfrm_statistics_fini(net);
2699}
2700
2701static struct pernet_operations __net_initdata xfrm_net_ops = {
2702        .init = xfrm_net_init,
2703        .exit = xfrm_net_exit,
2704};
2705
2706void __init xfrm_init(void)
2707{
2708        register_pernet_subsys(&xfrm_net_ops);
2709        xfrm_input_init();
2710}
2711
2712#ifdef CONFIG_AUDITSYSCALL
2713static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
2714                                         struct audit_buffer *audit_buf)
2715{
2716        struct xfrm_sec_ctx *ctx = xp->security;
2717        struct xfrm_selector *sel = &xp->selector;
2718
2719        if (ctx)
2720                audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
2721                                 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
2722
2723        switch(sel->family) {
2724        case AF_INET:
2725                audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
2726                if (sel->prefixlen_s != 32)
2727                        audit_log_format(audit_buf, " src_prefixlen=%d",
2728                                         sel->prefixlen_s);
2729                audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
2730                if (sel->prefixlen_d != 32)
2731                        audit_log_format(audit_buf, " dst_prefixlen=%d",
2732                                         sel->prefixlen_d);
2733                break;
2734        case AF_INET6:
2735                audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
2736                if (sel->prefixlen_s != 128)
2737                        audit_log_format(audit_buf, " src_prefixlen=%d",
2738                                         sel->prefixlen_s);
2739                audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
2740                if (sel->prefixlen_d != 128)
2741                        audit_log_format(audit_buf, " dst_prefixlen=%d",
2742                                         sel->prefixlen_d);
2743                break;
2744        }
2745}
2746
2747void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
2748                           uid_t auid, u32 sessionid, u32 secid)
2749{
2750        struct audit_buffer *audit_buf;
2751
2752        audit_buf = xfrm_audit_start("SPD-add");
2753        if (audit_buf == NULL)
2754                return;
2755        xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2756        audit_log_format(audit_buf, " res=%u", result);
2757        xfrm_audit_common_policyinfo(xp, audit_buf);
2758        audit_log_end(audit_buf);
2759}
2760EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
2761
2762void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
2763                              uid_t auid, u32 sessionid, u32 secid)
2764{
2765        struct audit_buffer *audit_buf;
2766
2767        audit_buf = xfrm_audit_start("SPD-delete");
2768        if (audit_buf == NULL)
2769                return;
2770        xfrm_audit_helper_usrinfo(auid, sessionid, secid, audit_buf);
2771        audit_log_format(audit_buf, " res=%u", result);
2772        xfrm_audit_common_policyinfo(xp, audit_buf);
2773        audit_log_end(audit_buf);
2774}
2775EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
2776#endif
2777
2778#ifdef CONFIG_XFRM_MIGRATE
2779static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
2780                                        const struct xfrm_selector *sel_tgt)
2781{
2782        if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
2783                if (sel_tgt->family == sel_cmp->family &&
2784                    xfrm_addr_cmp(&sel_tgt->daddr, &sel_cmp->daddr,
2785                                  sel_cmp->family) == 0 &&
2786                    xfrm_addr_cmp(&sel_tgt->saddr, &sel_cmp->saddr,
2787                                  sel_cmp->family) == 0 &&
2788                    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
2789                    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
2790                        return true;
2791                }
2792        } else {
2793                if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
2794                        return true;
2795                }
2796        }
2797        return false;
2798}
2799
2800static struct xfrm_policy * xfrm_migrate_policy_find(const struct xfrm_selector *sel,
2801                                                     u8 dir, u8 type)
2802{
2803        struct xfrm_policy *pol, *ret = NULL;
2804        struct hlist_node *entry;
2805        struct hlist_head *chain;
2806        u32 priority = ~0U;
2807
2808        read_lock_bh(&xfrm_policy_lock);
2809        chain = policy_hash_direct(&init_net, &sel->daddr, &sel->saddr, sel->family, dir);
2810        hlist_for_each_entry(pol, entry, chain, bydst) {
2811                if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2812                    pol->type == type) {
2813                        ret = pol;
2814                        priority = ret->priority;
2815                        break;
2816                }
2817        }
2818        chain = &init_net.xfrm.policy_inexact[dir];
2819        hlist_for_each_entry(pol, entry, chain, bydst) {
2820                if (xfrm_migrate_selector_match(sel, &pol->selector) &&
2821                    pol->type == type &&
2822                    pol->priority < priority) {
2823                        ret = pol;
2824                        break;
2825                }
2826        }
2827
2828        if (ret)
2829                xfrm_pol_hold(ret);
2830
2831        read_unlock_bh(&xfrm_policy_lock);
2832
2833        return ret;
2834}
2835
2836static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
2837{
2838        int match = 0;
2839
2840        if (t->mode == m->mode && t->id.proto == m->proto &&
2841            (m->reqid == 0 || t->reqid == m->reqid)) {
2842                switch (t->mode) {
2843                case XFRM_MODE_TUNNEL:
2844                case XFRM_MODE_BEET:
2845                        if (xfrm_addr_cmp(&t->id.daddr, &m->old_daddr,
2846                                          m->old_family) == 0 &&
2847                            xfrm_addr_cmp(&t->saddr, &m->old_saddr,
2848                                          m->old_family) == 0) {
2849                                match = 1;
2850                        }
2851                        break;
2852                case XFRM_MODE_TRANSPORT:
2853                        /* in case of transport mode, template does not store
2854                           any IP addresses, hence we just compare mode and
2855                           protocol */
2856                        match = 1;
2857                        break;
2858                default:
2859                        break;
2860                }
2861        }
2862        return match;
2863}
2864
2865/* update endpoint address(es) of template(s) */
2866static int xfrm_policy_migrate(struct xfrm_policy *pol,
2867                               struct xfrm_migrate *m, int num_migrate)
2868{
2869        struct xfrm_migrate *mp;
2870        int i, j, n = 0;
2871
2872        write_lock_bh(&pol->lock);
2873        if (unlikely(pol->walk.dead)) {
2874                /* target policy has been deleted */
2875                write_unlock_bh(&pol->lock);
2876                return -ENOENT;
2877        }
2878
2879        for (i = 0; i < pol->xfrm_nr; i++) {
2880                for (j = 0, mp = m; j < num_migrate; j++, mp++) {
2881                        if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
2882                                continue;
2883                        n++;
2884                        if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
2885                            pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
2886                                continue;
2887                        /* update endpoints */
2888                        memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
2889                               sizeof(pol->xfrm_vec[i].id.daddr));
2890                        memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
2891                               sizeof(pol->xfrm_vec[i].saddr));
2892                        pol->xfrm_vec[i].encap_family = mp->new_family;
2893                        /* flush bundles */
2894                        atomic_inc(&pol->genid);
2895                }
2896        }
2897
2898        write_unlock_bh(&pol->lock);
2899
2900        if (!n)
2901                return -ENODATA;
2902
2903        return 0;
2904}
2905
2906static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
2907{
2908        int i, j;
2909
2910        if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
2911                return -EINVAL;
2912
2913        for (i = 0; i < num_migrate; i++) {
2914                if ((xfrm_addr_cmp(&m[i].old_daddr, &m[i].new_daddr,
2915                                   m[i].old_family) == 0) &&
2916                    (xfrm_addr_cmp(&m[i].old_saddr, &m[i].new_saddr,
2917                                   m[i].old_family) == 0))
2918                        return -EINVAL;
2919                if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
2920                    xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
2921                        return -EINVAL;
2922
2923                /* check if there is any duplicated entry */
2924                for (j = i + 1; j < num_migrate; j++) {
2925                        if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
2926                                    sizeof(m[i].old_daddr)) &&
2927                            !memcmp(&m[i].old_saddr, &m[j].old_saddr,
2928                                    sizeof(m[i].old_saddr)) &&
2929                            m[i].proto == m[j].proto &&
2930                            m[i].mode == m[j].mode &&
2931                            m[i].reqid == m[j].reqid &&
2932                            m[i].old_family == m[j].old_family)
2933                                return -EINVAL;
2934                }
2935        }
2936
2937        return 0;
2938}
2939
2940int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
2941                 struct xfrm_migrate *m, int num_migrate,
2942                 struct xfrm_kmaddress *k)
2943{
2944        int i, err, nx_cur = 0, nx_new = 0;
2945        struct xfrm_policy *pol = NULL;
2946        struct xfrm_state *x, *xc;
2947        struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
2948        struct xfrm_state *x_new[XFRM_MAX_DEPTH];
2949        struct xfrm_migrate *mp;
2950
2951        if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
2952                goto out;
2953
2954        /* Stage 1 - find policy */
2955        if ((pol = xfrm_migrate_policy_find(sel, dir, type)) == NULL) {
2956                err = -ENOENT;
2957                goto out;
2958        }
2959
2960        /* Stage 2 - find and update state(s) */
2961        for (i = 0, mp = m; i < num_migrate; i++, mp++) {
2962                if ((x = xfrm_migrate_state_find(mp))) {
2963                        x_cur[nx_cur] = x;
2964                        nx_cur++;
2965                        if ((xc = xfrm_state_migrate(x, mp))) {
2966                                x_new[nx_new] = xc;
2967                                nx_new++;
2968                        } else {
2969                                err = -ENODATA;
2970                                goto restore_state;
2971                        }
2972                }
2973        }
2974
2975        /* Stage 3 - update policy */
2976        if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
2977                goto restore_state;
2978
2979        /* Stage 4 - delete old state(s) */
2980        if (nx_cur) {
2981                xfrm_states_put(x_cur, nx_cur);
2982                xfrm_states_delete(x_cur, nx_cur);
2983        }
2984
2985        /* Stage 5 - announce */
2986        km_migrate(sel, dir, type, m, num_migrate, k);
2987
2988        xfrm_pol_put(pol);
2989
2990        return 0;
2991out:
2992        return err;
2993
2994restore_state:
2995        if (pol)
2996                xfrm_pol_put(pol);
2997        if (nx_cur)
2998                xfrm_states_put(x_cur, nx_cur);
2999        if (nx_new)
3000                xfrm_states_delete(x_new, nx_new);
3001
3002        return err;
3003}
3004EXPORT_SYMBOL(xfrm_migrate);
3005#endif
3006
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