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v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * xfrm_policy.c
   4 *
   5 * Changes:
   6 *	Mitsuru KANDA @USAGI
   7 * 	Kazunori MIYAZAWA @USAGI
   8 * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   9 * 		IPv6 support
  10 * 	Kazunori MIYAZAWA @USAGI
  11 * 	YOSHIFUJI Hideaki
  12 * 		Split up af-specific portion
  13 *	Derek Atkins <derek@ihtfp.com>		Add the post_input processor
  14 *
  15 */
  16
  17#include <linux/err.h>
  18#include <linux/slab.h>
  19#include <linux/kmod.h>
  20#include <linux/list.h>
  21#include <linux/spinlock.h>
  22#include <linux/workqueue.h>
  23#include <linux/notifier.h>
  24#include <linux/netdevice.h>
  25#include <linux/netfilter.h>
  26#include <linux/module.h>
  27#include <linux/cache.h>
  28#include <linux/cpu.h>
  29#include <linux/audit.h>
  30#include <linux/rhashtable.h>
  31#include <linux/if_tunnel.h>
 
  32#include <net/dst.h>
  33#include <net/flow.h>
 
  34#include <net/xfrm.h>
  35#include <net/ip.h>
 
  36#if IS_ENABLED(CONFIG_IPV6_MIP6)
  37#include <net/mip6.h>
  38#endif
  39#ifdef CONFIG_XFRM_STATISTICS
  40#include <net/snmp.h>
  41#endif
 
 
 
  42
  43#include "xfrm_hash.h"
  44
  45#define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  46#define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  47#define XFRM_MAX_QUEUE_LEN	100
  48
  49struct xfrm_flo {
  50	struct dst_entry *dst_orig;
  51	u8 flags;
  52};
  53
  54/* prefixes smaller than this are stored in lists, not trees. */
  55#define INEXACT_PREFIXLEN_IPV4	16
  56#define INEXACT_PREFIXLEN_IPV6	48
  57
  58struct xfrm_pol_inexact_node {
  59	struct rb_node node;
  60	union {
  61		xfrm_address_t addr;
  62		struct rcu_head rcu;
  63	};
  64	u8 prefixlen;
  65
  66	struct rb_root root;
  67
  68	/* the policies matching this node, can be empty list */
  69	struct hlist_head hhead;
  70};
  71
  72/* xfrm inexact policy search tree:
  73 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
  74 *  |
  75 * +---- root_d: sorted by daddr:prefix
  76 * |                 |
  77 * |        xfrm_pol_inexact_node
  78 * |                 |
  79 * |                 +- root: sorted by saddr/prefix
  80 * |                 |              |
  81 * |                 |         xfrm_pol_inexact_node
  82 * |                 |              |
  83 * |                 |              + root: unused
  84 * |                 |              |
  85 * |                 |              + hhead: saddr:daddr policies
  86 * |                 |
  87 * |                 +- coarse policies and all any:daddr policies
  88 * |
  89 * +---- root_s: sorted by saddr:prefix
  90 * |                 |
  91 * |        xfrm_pol_inexact_node
  92 * |                 |
  93 * |                 + root: unused
  94 * |                 |
  95 * |                 + hhead: saddr:any policies
  96 * |
  97 * +---- coarse policies and all any:any policies
  98 *
  99 * Lookups return four candidate lists:
 100 * 1. any:any list from top-level xfrm_pol_inexact_bin
 101 * 2. any:daddr list from daddr tree
 102 * 3. saddr:daddr list from 2nd level daddr tree
 103 * 4. saddr:any list from saddr tree
 104 *
 105 * This result set then needs to be searched for the policy with
 106 * the lowest priority.  If two results have same prio, youngest one wins.
 107 */
 108
 109struct xfrm_pol_inexact_key {
 110	possible_net_t net;
 111	u32 if_id;
 112	u16 family;
 113	u8 dir, type;
 114};
 115
 116struct xfrm_pol_inexact_bin {
 117	struct xfrm_pol_inexact_key k;
 118	struct rhash_head head;
 119	/* list containing '*:*' policies */
 120	struct hlist_head hhead;
 121
 122	seqcount_t count;
 123	/* tree sorted by daddr/prefix */
 124	struct rb_root root_d;
 125
 126	/* tree sorted by saddr/prefix */
 127	struct rb_root root_s;
 128
 129	/* slow path below */
 130	struct list_head inexact_bins;
 131	struct rcu_head rcu;
 132};
 133
 134enum xfrm_pol_inexact_candidate_type {
 135	XFRM_POL_CAND_BOTH,
 136	XFRM_POL_CAND_SADDR,
 137	XFRM_POL_CAND_DADDR,
 138	XFRM_POL_CAND_ANY,
 139
 140	XFRM_POL_CAND_MAX,
 141};
 142
 143struct xfrm_pol_inexact_candidates {
 144	struct hlist_head *res[XFRM_POL_CAND_MAX];
 145};
 146
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 147static DEFINE_SPINLOCK(xfrm_if_cb_lock);
 148static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
 149
 150static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
 151static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 152						__read_mostly;
 153
 154static struct kmem_cache *xfrm_dst_cache __ro_after_init;
 155static __read_mostly seqcount_t xfrm_policy_hash_generation;
 156
 157static struct rhashtable xfrm_policy_inexact_table;
 158static const struct rhashtable_params xfrm_pol_inexact_params;
 159
 160static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
 161static int stale_bundle(struct dst_entry *dst);
 162static int xfrm_bundle_ok(struct xfrm_dst *xdst);
 163static void xfrm_policy_queue_process(struct timer_list *t);
 164
 165static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 166static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 167						int dir);
 168
 169static struct xfrm_pol_inexact_bin *
 170xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
 171			   u32 if_id);
 172
 173static struct xfrm_pol_inexact_bin *
 174xfrm_policy_inexact_lookup_rcu(struct net *net,
 175			       u8 type, u16 family, u8 dir, u32 if_id);
 176static struct xfrm_policy *
 177xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
 178			bool excl);
 179static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
 180					    struct xfrm_policy *policy);
 181
 182static bool
 183xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
 184				    struct xfrm_pol_inexact_bin *b,
 185				    const xfrm_address_t *saddr,
 186				    const xfrm_address_t *daddr);
 187
 188static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
 189{
 190	return refcount_inc_not_zero(&policy->refcnt);
 191}
 192
 193static inline bool
 194__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 195{
 196	const struct flowi4 *fl4 = &fl->u.ip4;
 197
 198	return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
 199		addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
 200		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
 201		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
 202		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
 203		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 204}
 205
 206static inline bool
 207__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 208{
 209	const struct flowi6 *fl6 = &fl->u.ip6;
 210
 211	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
 212		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
 213		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
 214		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
 215		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
 216		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 217}
 218
 219bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
 220			 unsigned short family)
 221{
 222	switch (family) {
 223	case AF_INET:
 224		return __xfrm4_selector_match(sel, fl);
 225	case AF_INET6:
 226		return __xfrm6_selector_match(sel, fl);
 227	}
 228	return false;
 229}
 230
 231static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 232{
 233	const struct xfrm_policy_afinfo *afinfo;
 234
 235	if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 236		return NULL;
 237	rcu_read_lock();
 238	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 239	if (unlikely(!afinfo))
 240		rcu_read_unlock();
 241	return afinfo;
 242}
 243
 244/* Called with rcu_read_lock(). */
 245static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 246{
 247	return rcu_dereference(xfrm_if_cb);
 248}
 249
 250struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 251				    const xfrm_address_t *saddr,
 252				    const xfrm_address_t *daddr,
 253				    int family, u32 mark)
 254{
 255	const struct xfrm_policy_afinfo *afinfo;
 256	struct dst_entry *dst;
 257
 258	afinfo = xfrm_policy_get_afinfo(family);
 259	if (unlikely(afinfo == NULL))
 260		return ERR_PTR(-EAFNOSUPPORT);
 261
 262	dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 263
 264	rcu_read_unlock();
 265
 266	return dst;
 267}
 268EXPORT_SYMBOL(__xfrm_dst_lookup);
 269
 270static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 271						int tos, int oif,
 272						xfrm_address_t *prev_saddr,
 273						xfrm_address_t *prev_daddr,
 274						int family, u32 mark)
 275{
 276	struct net *net = xs_net(x);
 277	xfrm_address_t *saddr = &x->props.saddr;
 278	xfrm_address_t *daddr = &x->id.daddr;
 279	struct dst_entry *dst;
 280
 281	if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 282		saddr = x->coaddr;
 283		daddr = prev_daddr;
 284	}
 285	if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 286		saddr = prev_saddr;
 287		daddr = x->coaddr;
 288	}
 289
 290	dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 291
 292	if (!IS_ERR(dst)) {
 293		if (prev_saddr != saddr)
 294			memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 295		if (prev_daddr != daddr)
 296			memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 297	}
 298
 299	return dst;
 300}
 301
 302static inline unsigned long make_jiffies(long secs)
 303{
 304	if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 305		return MAX_SCHEDULE_TIMEOUT-1;
 306	else
 307		return secs*HZ;
 308}
 309
 310static void xfrm_policy_timer(struct timer_list *t)
 311{
 312	struct xfrm_policy *xp = from_timer(xp, t, timer);
 313	time64_t now = ktime_get_real_seconds();
 314	time64_t next = TIME64_MAX;
 315	int warn = 0;
 316	int dir;
 317
 318	read_lock(&xp->lock);
 319
 320	if (unlikely(xp->walk.dead))
 321		goto out;
 322
 323	dir = xfrm_policy_id2dir(xp->index);
 324
 325	if (xp->lft.hard_add_expires_seconds) {
 326		time64_t tmo = xp->lft.hard_add_expires_seconds +
 327			xp->curlft.add_time - now;
 328		if (tmo <= 0)
 329			goto expired;
 330		if (tmo < next)
 331			next = tmo;
 332	}
 333	if (xp->lft.hard_use_expires_seconds) {
 334		time64_t tmo = xp->lft.hard_use_expires_seconds +
 335			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
 336		if (tmo <= 0)
 337			goto expired;
 338		if (tmo < next)
 339			next = tmo;
 340	}
 341	if (xp->lft.soft_add_expires_seconds) {
 342		time64_t tmo = xp->lft.soft_add_expires_seconds +
 343			xp->curlft.add_time - now;
 344		if (tmo <= 0) {
 345			warn = 1;
 346			tmo = XFRM_KM_TIMEOUT;
 347		}
 348		if (tmo < next)
 349			next = tmo;
 350	}
 351	if (xp->lft.soft_use_expires_seconds) {
 352		time64_t tmo = xp->lft.soft_use_expires_seconds +
 353			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
 354		if (tmo <= 0) {
 355			warn = 1;
 356			tmo = XFRM_KM_TIMEOUT;
 357		}
 358		if (tmo < next)
 359			next = tmo;
 360	}
 361
 362	if (warn)
 363		km_policy_expired(xp, dir, 0, 0);
 364	if (next != TIME64_MAX &&
 365	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 366		xfrm_pol_hold(xp);
 367
 368out:
 369	read_unlock(&xp->lock);
 370	xfrm_pol_put(xp);
 371	return;
 372
 373expired:
 374	read_unlock(&xp->lock);
 375	if (!xfrm_policy_delete(xp, dir))
 376		km_policy_expired(xp, dir, 1, 0);
 377	xfrm_pol_put(xp);
 378}
 379
 380/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 381 * SPD calls.
 382 */
 383
 384struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 385{
 386	struct xfrm_policy *policy;
 387
 388	policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 389
 390	if (policy) {
 391		write_pnet(&policy->xp_net, net);
 392		INIT_LIST_HEAD(&policy->walk.all);
 393		INIT_HLIST_NODE(&policy->bydst_inexact_list);
 394		INIT_HLIST_NODE(&policy->bydst);
 395		INIT_HLIST_NODE(&policy->byidx);
 396		rwlock_init(&policy->lock);
 397		refcount_set(&policy->refcnt, 1);
 398		skb_queue_head_init(&policy->polq.hold_queue);
 399		timer_setup(&policy->timer, xfrm_policy_timer, 0);
 400		timer_setup(&policy->polq.hold_timer,
 401			    xfrm_policy_queue_process, 0);
 402	}
 403	return policy;
 404}
 405EXPORT_SYMBOL(xfrm_policy_alloc);
 406
 407static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 408{
 409	struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 410
 411	security_xfrm_policy_free(policy->security);
 412	kfree(policy);
 413}
 414
 415/* Destroy xfrm_policy: descendant resources must be released to this moment. */
 416
 417void xfrm_policy_destroy(struct xfrm_policy *policy)
 418{
 419	BUG_ON(!policy->walk.dead);
 420
 421	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 422		BUG();
 423
 
 424	call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 425}
 426EXPORT_SYMBOL(xfrm_policy_destroy);
 427
 428/* Rule must be locked. Release descendant resources, announce
 429 * entry dead. The rule must be unlinked from lists to the moment.
 430 */
 431
 432static void xfrm_policy_kill(struct xfrm_policy *policy)
 433{
 
 434	policy->walk.dead = 1;
 
 435
 436	atomic_inc(&policy->genid);
 437
 438	if (del_timer(&policy->polq.hold_timer))
 439		xfrm_pol_put(policy);
 440	skb_queue_purge(&policy->polq.hold_queue);
 441
 442	if (del_timer(&policy->timer))
 443		xfrm_pol_put(policy);
 444
 445	xfrm_pol_put(policy);
 446}
 447
 448static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 449
 450static inline unsigned int idx_hash(struct net *net, u32 index)
 451{
 452	return __idx_hash(index, net->xfrm.policy_idx_hmask);
 453}
 454
 455/* calculate policy hash thresholds */
 456static void __get_hash_thresh(struct net *net,
 457			      unsigned short family, int dir,
 458			      u8 *dbits, u8 *sbits)
 459{
 460	switch (family) {
 461	case AF_INET:
 462		*dbits = net->xfrm.policy_bydst[dir].dbits4;
 463		*sbits = net->xfrm.policy_bydst[dir].sbits4;
 464		break;
 465
 466	case AF_INET6:
 467		*dbits = net->xfrm.policy_bydst[dir].dbits6;
 468		*sbits = net->xfrm.policy_bydst[dir].sbits6;
 469		break;
 470
 471	default:
 472		*dbits = 0;
 473		*sbits = 0;
 474	}
 475}
 476
 477static struct hlist_head *policy_hash_bysel(struct net *net,
 478					    const struct xfrm_selector *sel,
 479					    unsigned short family, int dir)
 480{
 481	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 482	unsigned int hash;
 483	u8 dbits;
 484	u8 sbits;
 485
 486	__get_hash_thresh(net, family, dir, &dbits, &sbits);
 487	hash = __sel_hash(sel, family, hmask, dbits, sbits);
 488
 489	if (hash == hmask + 1)
 490		return NULL;
 491
 492	return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 493		     lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 494}
 495
 496static struct hlist_head *policy_hash_direct(struct net *net,
 497					     const xfrm_address_t *daddr,
 498					     const xfrm_address_t *saddr,
 499					     unsigned short family, int dir)
 500{
 501	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 502	unsigned int hash;
 503	u8 dbits;
 504	u8 sbits;
 505
 506	__get_hash_thresh(net, family, dir, &dbits, &sbits);
 507	hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 508
 509	return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 510		     lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 511}
 512
 513static void xfrm_dst_hash_transfer(struct net *net,
 514				   struct hlist_head *list,
 515				   struct hlist_head *ndsttable,
 516				   unsigned int nhashmask,
 517				   int dir)
 518{
 519	struct hlist_node *tmp, *entry0 = NULL;
 520	struct xfrm_policy *pol;
 521	unsigned int h0 = 0;
 522	u8 dbits;
 523	u8 sbits;
 524
 525redo:
 526	hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 527		unsigned int h;
 528
 529		__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 530		h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 531				pol->family, nhashmask, dbits, sbits);
 532		if (!entry0) {
 533			hlist_del_rcu(&pol->bydst);
 534			hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 535			h0 = h;
 536		} else {
 537			if (h != h0)
 538				continue;
 539			hlist_del_rcu(&pol->bydst);
 540			hlist_add_behind_rcu(&pol->bydst, entry0);
 541		}
 542		entry0 = &pol->bydst;
 543	}
 544	if (!hlist_empty(list)) {
 545		entry0 = NULL;
 546		goto redo;
 547	}
 548}
 549
 550static void xfrm_idx_hash_transfer(struct hlist_head *list,
 551				   struct hlist_head *nidxtable,
 552				   unsigned int nhashmask)
 553{
 554	struct hlist_node *tmp;
 555	struct xfrm_policy *pol;
 556
 557	hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 558		unsigned int h;
 559
 560		h = __idx_hash(pol->index, nhashmask);
 561		hlist_add_head(&pol->byidx, nidxtable+h);
 562	}
 563}
 564
 565static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 566{
 567	return ((old_hmask + 1) << 1) - 1;
 568}
 569
 570static void xfrm_bydst_resize(struct net *net, int dir)
 571{
 572	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 573	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 574	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 575	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 576	struct hlist_head *odst;
 577	int i;
 578
 579	if (!ndst)
 580		return;
 581
 582	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 583	write_seqcount_begin(&xfrm_policy_hash_generation);
 584
 585	odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 586				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 587
 588	for (i = hmask; i >= 0; i--)
 589		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 590
 591	rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 592	net->xfrm.policy_bydst[dir].hmask = nhashmask;
 593
 594	write_seqcount_end(&xfrm_policy_hash_generation);
 595	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 596
 597	synchronize_rcu();
 598
 599	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 600}
 601
 602static void xfrm_byidx_resize(struct net *net, int total)
 603{
 604	unsigned int hmask = net->xfrm.policy_idx_hmask;
 605	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 606	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 607	struct hlist_head *oidx = net->xfrm.policy_byidx;
 608	struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 609	int i;
 610
 611	if (!nidx)
 612		return;
 613
 614	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 615
 616	for (i = hmask; i >= 0; i--)
 617		xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 618
 619	net->xfrm.policy_byidx = nidx;
 620	net->xfrm.policy_idx_hmask = nhashmask;
 621
 622	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 623
 624	xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 625}
 626
 627static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 628{
 629	unsigned int cnt = net->xfrm.policy_count[dir];
 630	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 631
 632	if (total)
 633		*total += cnt;
 634
 635	if ((hmask + 1) < xfrm_policy_hashmax &&
 636	    cnt > hmask)
 637		return 1;
 638
 639	return 0;
 640}
 641
 642static inline int xfrm_byidx_should_resize(struct net *net, int total)
 643{
 644	unsigned int hmask = net->xfrm.policy_idx_hmask;
 645
 646	if ((hmask + 1) < xfrm_policy_hashmax &&
 647	    total > hmask)
 648		return 1;
 649
 650	return 0;
 651}
 652
 653void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 654{
 655	si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 656	si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 657	si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 658	si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 659	si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 660	si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 661	si->spdhcnt = net->xfrm.policy_idx_hmask;
 662	si->spdhmcnt = xfrm_policy_hashmax;
 663}
 664EXPORT_SYMBOL(xfrm_spd_getinfo);
 665
 666static DEFINE_MUTEX(hash_resize_mutex);
 667static void xfrm_hash_resize(struct work_struct *work)
 668{
 669	struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 670	int dir, total;
 671
 672	mutex_lock(&hash_resize_mutex);
 673
 674	total = 0;
 675	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 676		if (xfrm_bydst_should_resize(net, dir, &total))
 677			xfrm_bydst_resize(net, dir);
 678	}
 679	if (xfrm_byidx_should_resize(net, total))
 680		xfrm_byidx_resize(net, total);
 681
 682	mutex_unlock(&hash_resize_mutex);
 683}
 684
 685/* Make sure *pol can be inserted into fastbin.
 686 * Useful to check that later insert requests will be sucessful
 687 * (provided xfrm_policy_lock is held throughout).
 688 */
 689static struct xfrm_pol_inexact_bin *
 690xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
 691{
 692	struct xfrm_pol_inexact_bin *bin, *prev;
 693	struct xfrm_pol_inexact_key k = {
 694		.family = pol->family,
 695		.type = pol->type,
 696		.dir = dir,
 697		.if_id = pol->if_id,
 698	};
 699	struct net *net = xp_net(pol);
 700
 701	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
 702
 703	write_pnet(&k.net, net);
 704	bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
 705				     xfrm_pol_inexact_params);
 706	if (bin)
 707		return bin;
 708
 709	bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
 710	if (!bin)
 711		return NULL;
 712
 713	bin->k = k;
 714	INIT_HLIST_HEAD(&bin->hhead);
 715	bin->root_d = RB_ROOT;
 716	bin->root_s = RB_ROOT;
 717	seqcount_init(&bin->count);
 718
 719	prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
 720						&bin->k, &bin->head,
 721						xfrm_pol_inexact_params);
 722	if (!prev) {
 723		list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
 724		return bin;
 725	}
 726
 727	kfree(bin);
 728
 729	return IS_ERR(prev) ? NULL : prev;
 730}
 731
 732static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
 733					       int family, u8 prefixlen)
 734{
 735	if (xfrm_addr_any(addr, family))
 736		return true;
 737
 738	if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
 739		return true;
 740
 741	if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
 742		return true;
 743
 744	return false;
 745}
 746
 747static bool
 748xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
 749{
 750	const xfrm_address_t *addr;
 751	bool saddr_any, daddr_any;
 752	u8 prefixlen;
 753
 754	addr = &policy->selector.saddr;
 755	prefixlen = policy->selector.prefixlen_s;
 756
 757	saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 758						       policy->family,
 759						       prefixlen);
 760	addr = &policy->selector.daddr;
 761	prefixlen = policy->selector.prefixlen_d;
 762	daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 763						       policy->family,
 764						       prefixlen);
 765	return saddr_any && daddr_any;
 766}
 767
 768static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
 769				       const xfrm_address_t *addr, u8 prefixlen)
 770{
 771	node->addr = *addr;
 772	node->prefixlen = prefixlen;
 773}
 774
 775static struct xfrm_pol_inexact_node *
 776xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
 777{
 778	struct xfrm_pol_inexact_node *node;
 779
 780	node = kzalloc(sizeof(*node), GFP_ATOMIC);
 781	if (node)
 782		xfrm_pol_inexact_node_init(node, addr, prefixlen);
 783
 784	return node;
 785}
 786
 787static int xfrm_policy_addr_delta(const xfrm_address_t *a,
 788				  const xfrm_address_t *b,
 789				  u8 prefixlen, u16 family)
 790{
 
 791	unsigned int pdw, pbi;
 792	int delta = 0;
 793
 794	switch (family) {
 795	case AF_INET:
 796		if (sizeof(long) == 4 && prefixlen == 0)
 797			return ntohl(a->a4) - ntohl(b->a4);
 798		return (ntohl(a->a4) & ((~0UL << (32 - prefixlen)))) -
 799		       (ntohl(b->a4) & ((~0UL << (32 - prefixlen))));
 
 
 
 
 
 
 800	case AF_INET6:
 801		pdw = prefixlen >> 5;
 802		pbi = prefixlen & 0x1f;
 803
 804		if (pdw) {
 805			delta = memcmp(a->a6, b->a6, pdw << 2);
 806			if (delta)
 807				return delta;
 808		}
 809		if (pbi) {
 810			u32 mask = ~0u << (32 - pbi);
 811
 812			delta = (ntohl(a->a6[pdw]) & mask) -
 813				(ntohl(b->a6[pdw]) & mask);
 
 
 
 814		}
 815		break;
 816	default:
 817		break;
 818	}
 819
 820	return delta;
 821}
 822
 823static void xfrm_policy_inexact_list_reinsert(struct net *net,
 824					      struct xfrm_pol_inexact_node *n,
 825					      u16 family)
 826{
 827	unsigned int matched_s, matched_d;
 828	struct xfrm_policy *policy, *p;
 829
 830	matched_s = 0;
 831	matched_d = 0;
 832
 833	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 834		struct hlist_node *newpos = NULL;
 835		bool matches_s, matches_d;
 836
 837		if (!policy->bydst_reinsert)
 838			continue;
 839
 840		WARN_ON_ONCE(policy->family != family);
 841
 842		policy->bydst_reinsert = false;
 843		hlist_for_each_entry(p, &n->hhead, bydst) {
 844			if (policy->priority > p->priority)
 845				newpos = &p->bydst;
 846			else if (policy->priority == p->priority &&
 847				 policy->pos > p->pos)
 848				newpos = &p->bydst;
 849			else
 850				break;
 851		}
 852
 853		if (newpos)
 854			hlist_add_behind_rcu(&policy->bydst, newpos);
 855		else
 856			hlist_add_head_rcu(&policy->bydst, &n->hhead);
 857
 858		/* paranoia checks follow.
 859		 * Check that the reinserted policy matches at least
 860		 * saddr or daddr for current node prefix.
 861		 *
 862		 * Matching both is fine, matching saddr in one policy
 863		 * (but not daddr) and then matching only daddr in another
 864		 * is a bug.
 865		 */
 866		matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
 867						   &n->addr,
 868						   n->prefixlen,
 869						   family) == 0;
 870		matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
 871						   &n->addr,
 872						   n->prefixlen,
 873						   family) == 0;
 874		if (matches_s && matches_d)
 875			continue;
 876
 877		WARN_ON_ONCE(!matches_s && !matches_d);
 878		if (matches_s)
 879			matched_s++;
 880		if (matches_d)
 881			matched_d++;
 882		WARN_ON_ONCE(matched_s && matched_d);
 883	}
 884}
 885
 886static void xfrm_policy_inexact_node_reinsert(struct net *net,
 887					      struct xfrm_pol_inexact_node *n,
 888					      struct rb_root *new,
 889					      u16 family)
 890{
 891	struct xfrm_pol_inexact_node *node;
 892	struct rb_node **p, *parent;
 893
 894	/* we should not have another subtree here */
 895	WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
 896restart:
 897	parent = NULL;
 898	p = &new->rb_node;
 899	while (*p) {
 900		u8 prefixlen;
 901		int delta;
 902
 903		parent = *p;
 904		node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 905
 906		prefixlen = min(node->prefixlen, n->prefixlen);
 907
 908		delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
 909					       prefixlen, family);
 910		if (delta < 0) {
 911			p = &parent->rb_left;
 912		} else if (delta > 0) {
 913			p = &parent->rb_right;
 914		} else {
 915			bool same_prefixlen = node->prefixlen == n->prefixlen;
 916			struct xfrm_policy *tmp;
 917
 918			hlist_for_each_entry(tmp, &n->hhead, bydst) {
 919				tmp->bydst_reinsert = true;
 920				hlist_del_rcu(&tmp->bydst);
 921			}
 922
 923			node->prefixlen = prefixlen;
 924
 925			xfrm_policy_inexact_list_reinsert(net, node, family);
 926
 927			if (same_prefixlen) {
 928				kfree_rcu(n, rcu);
 929				return;
 930			}
 931
 932			rb_erase(*p, new);
 933			kfree_rcu(n, rcu);
 934			n = node;
 935			goto restart;
 936		}
 937	}
 938
 939	rb_link_node_rcu(&n->node, parent, p);
 940	rb_insert_color(&n->node, new);
 941}
 942
 943/* merge nodes v and n */
 944static void xfrm_policy_inexact_node_merge(struct net *net,
 945					   struct xfrm_pol_inexact_node *v,
 946					   struct xfrm_pol_inexact_node *n,
 947					   u16 family)
 948{
 949	struct xfrm_pol_inexact_node *node;
 950	struct xfrm_policy *tmp;
 951	struct rb_node *rnode;
 952
 953	/* To-be-merged node v has a subtree.
 954	 *
 955	 * Dismantle it and insert its nodes to n->root.
 956	 */
 957	while ((rnode = rb_first(&v->root)) != NULL) {
 958		node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
 959		rb_erase(&node->node, &v->root);
 960		xfrm_policy_inexact_node_reinsert(net, node, &n->root,
 961						  family);
 962	}
 963
 964	hlist_for_each_entry(tmp, &v->hhead, bydst) {
 965		tmp->bydst_reinsert = true;
 966		hlist_del_rcu(&tmp->bydst);
 967	}
 968
 969	xfrm_policy_inexact_list_reinsert(net, n, family);
 970}
 971
 972static struct xfrm_pol_inexact_node *
 973xfrm_policy_inexact_insert_node(struct net *net,
 974				struct rb_root *root,
 975				xfrm_address_t *addr,
 976				u16 family, u8 prefixlen, u8 dir)
 977{
 978	struct xfrm_pol_inexact_node *cached = NULL;
 979	struct rb_node **p, *parent = NULL;
 980	struct xfrm_pol_inexact_node *node;
 981
 982	p = &root->rb_node;
 983	while (*p) {
 984		int delta;
 985
 986		parent = *p;
 987		node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 988
 989		delta = xfrm_policy_addr_delta(addr, &node->addr,
 990					       node->prefixlen,
 991					       family);
 992		if (delta == 0 && prefixlen >= node->prefixlen) {
 993			WARN_ON_ONCE(cached); /* ipsec policies got lost */
 994			return node;
 995		}
 996
 997		if (delta < 0)
 998			p = &parent->rb_left;
 999		else
1000			p = &parent->rb_right;
1001
1002		if (prefixlen < node->prefixlen) {
1003			delta = xfrm_policy_addr_delta(addr, &node->addr,
1004						       prefixlen,
1005						       family);
1006			if (delta)
1007				continue;
1008
1009			/* This node is a subnet of the new prefix. It needs
1010			 * to be removed and re-inserted with the smaller
1011			 * prefix and all nodes that are now also covered
1012			 * by the reduced prefixlen.
1013			 */
1014			rb_erase(&node->node, root);
1015
1016			if (!cached) {
1017				xfrm_pol_inexact_node_init(node, addr,
1018							   prefixlen);
1019				cached = node;
1020			} else {
1021				/* This node also falls within the new
1022				 * prefixlen. Merge the to-be-reinserted
1023				 * node and this one.
1024				 */
1025				xfrm_policy_inexact_node_merge(net, node,
1026							       cached, family);
1027				kfree_rcu(node, rcu);
1028			}
1029
1030			/* restart */
1031			p = &root->rb_node;
1032			parent = NULL;
1033		}
1034	}
1035
1036	node = cached;
1037	if (!node) {
1038		node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1039		if (!node)
1040			return NULL;
1041	}
1042
1043	rb_link_node_rcu(&node->node, parent, p);
1044	rb_insert_color(&node->node, root);
1045
1046	return node;
1047}
1048
1049static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1050{
1051	struct xfrm_pol_inexact_node *node;
1052	struct rb_node *rn = rb_first(r);
1053
1054	while (rn) {
1055		node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1056
1057		xfrm_policy_inexact_gc_tree(&node->root, rm);
1058		rn = rb_next(rn);
1059
1060		if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1061			WARN_ON_ONCE(rm);
1062			continue;
1063		}
1064
1065		rb_erase(&node->node, r);
1066		kfree_rcu(node, rcu);
1067	}
1068}
1069
1070static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1071{
1072	write_seqcount_begin(&b->count);
1073	xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1074	xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1075	write_seqcount_end(&b->count);
1076
1077	if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1078	    !hlist_empty(&b->hhead)) {
1079		WARN_ON_ONCE(net_exit);
1080		return;
1081	}
1082
1083	if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1084				   xfrm_pol_inexact_params) == 0) {
1085		list_del(&b->inexact_bins);
1086		kfree_rcu(b, rcu);
1087	}
1088}
1089
1090static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1091{
1092	struct net *net = read_pnet(&b->k.net);
1093
1094	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1095	__xfrm_policy_inexact_prune_bin(b, false);
1096	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1097}
1098
1099static void __xfrm_policy_inexact_flush(struct net *net)
1100{
1101	struct xfrm_pol_inexact_bin *bin, *t;
1102
1103	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1104
1105	list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1106		__xfrm_policy_inexact_prune_bin(bin, false);
1107}
1108
1109static struct hlist_head *
1110xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1111				struct xfrm_policy *policy, u8 dir)
1112{
1113	struct xfrm_pol_inexact_node *n;
1114	struct net *net;
1115
1116	net = xp_net(policy);
1117	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1118
1119	if (xfrm_policy_inexact_insert_use_any_list(policy))
1120		return &bin->hhead;
1121
1122	if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1123					       policy->family,
1124					       policy->selector.prefixlen_d)) {
1125		write_seqcount_begin(&bin->count);
1126		n = xfrm_policy_inexact_insert_node(net,
1127						    &bin->root_s,
1128						    &policy->selector.saddr,
1129						    policy->family,
1130						    policy->selector.prefixlen_s,
1131						    dir);
1132		write_seqcount_end(&bin->count);
1133		if (!n)
1134			return NULL;
1135
1136		return &n->hhead;
1137	}
1138
1139	/* daddr is fixed */
1140	write_seqcount_begin(&bin->count);
1141	n = xfrm_policy_inexact_insert_node(net,
1142					    &bin->root_d,
1143					    &policy->selector.daddr,
1144					    policy->family,
1145					    policy->selector.prefixlen_d, dir);
1146	write_seqcount_end(&bin->count);
1147	if (!n)
1148		return NULL;
1149
1150	/* saddr is wildcard */
1151	if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1152					       policy->family,
1153					       policy->selector.prefixlen_s))
1154		return &n->hhead;
1155
1156	write_seqcount_begin(&bin->count);
1157	n = xfrm_policy_inexact_insert_node(net,
1158					    &n->root,
1159					    &policy->selector.saddr,
1160					    policy->family,
1161					    policy->selector.prefixlen_s, dir);
1162	write_seqcount_end(&bin->count);
1163	if (!n)
1164		return NULL;
1165
1166	return &n->hhead;
1167}
1168
1169static struct xfrm_policy *
1170xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1171{
1172	struct xfrm_pol_inexact_bin *bin;
1173	struct xfrm_policy *delpol;
1174	struct hlist_head *chain;
1175	struct net *net;
1176
1177	bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1178	if (!bin)
1179		return ERR_PTR(-ENOMEM);
1180
1181	net = xp_net(policy);
1182	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1183
1184	chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1185	if (!chain) {
1186		__xfrm_policy_inexact_prune_bin(bin, false);
1187		return ERR_PTR(-ENOMEM);
1188	}
1189
1190	delpol = xfrm_policy_insert_list(chain, policy, excl);
1191	if (delpol && excl) {
1192		__xfrm_policy_inexact_prune_bin(bin, false);
1193		return ERR_PTR(-EEXIST);
1194	}
1195
1196	chain = &net->xfrm.policy_inexact[dir];
1197	xfrm_policy_insert_inexact_list(chain, policy);
1198
1199	if (delpol)
1200		__xfrm_policy_inexact_prune_bin(bin, false);
1201
1202	return delpol;
1203}
1204
1205static void xfrm_hash_rebuild(struct work_struct *work)
1206{
1207	struct net *net = container_of(work, struct net,
1208				       xfrm.policy_hthresh.work);
1209	unsigned int hmask;
1210	struct xfrm_policy *pol;
1211	struct xfrm_policy *policy;
1212	struct hlist_head *chain;
1213	struct hlist_head *odst;
1214	struct hlist_node *newpos;
1215	int i;
1216	int dir;
1217	unsigned seq;
1218	u8 lbits4, rbits4, lbits6, rbits6;
1219
1220	mutex_lock(&hash_resize_mutex);
1221
1222	/* read selector prefixlen thresholds */
1223	do {
1224		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1225
1226		lbits4 = net->xfrm.policy_hthresh.lbits4;
1227		rbits4 = net->xfrm.policy_hthresh.rbits4;
1228		lbits6 = net->xfrm.policy_hthresh.lbits6;
1229		rbits6 = net->xfrm.policy_hthresh.rbits6;
1230	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1231
1232	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1233	write_seqcount_begin(&xfrm_policy_hash_generation);
1234
1235	/* make sure that we can insert the indirect policies again before
1236	 * we start with destructive action.
1237	 */
1238	list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1239		struct xfrm_pol_inexact_bin *bin;
1240		u8 dbits, sbits;
1241
 
 
 
1242		dir = xfrm_policy_id2dir(policy->index);
1243		if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
1244			continue;
1245
1246		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1247			if (policy->family == AF_INET) {
1248				dbits = rbits4;
1249				sbits = lbits4;
1250			} else {
1251				dbits = rbits6;
1252				sbits = lbits6;
1253			}
1254		} else {
1255			if (policy->family == AF_INET) {
1256				dbits = lbits4;
1257				sbits = rbits4;
1258			} else {
1259				dbits = lbits6;
1260				sbits = rbits6;
1261			}
1262		}
1263
1264		if (policy->selector.prefixlen_d < dbits ||
1265		    policy->selector.prefixlen_s < sbits)
1266			continue;
1267
1268		bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1269		if (!bin)
1270			goto out_unlock;
1271
1272		if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1273			goto out_unlock;
1274	}
1275
1276	/* reset the bydst and inexact table in all directions */
1277	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1278		struct hlist_node *n;
1279
1280		hlist_for_each_entry_safe(policy, n,
1281					  &net->xfrm.policy_inexact[dir],
1282					  bydst_inexact_list) {
1283			hlist_del_rcu(&policy->bydst);
1284			hlist_del_init(&policy->bydst_inexact_list);
1285		}
1286
1287		hmask = net->xfrm.policy_bydst[dir].hmask;
1288		odst = net->xfrm.policy_bydst[dir].table;
1289		for (i = hmask; i >= 0; i--) {
1290			hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1291				hlist_del_rcu(&policy->bydst);
1292		}
1293		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1294			/* dir out => dst = remote, src = local */
1295			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1296			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1297			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1298			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1299		} else {
1300			/* dir in/fwd => dst = local, src = remote */
1301			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1302			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1303			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1304			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1305		}
1306	}
1307
1308	/* re-insert all policies by order of creation */
1309	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1310		if (policy->walk.dead)
1311			continue;
1312		dir = xfrm_policy_id2dir(policy->index);
1313		if (dir >= XFRM_POLICY_MAX) {
1314			/* skip socket policies */
1315			continue;
1316		}
1317		newpos = NULL;
1318		chain = policy_hash_bysel(net, &policy->selector,
1319					  policy->family, dir);
1320
1321		if (!chain) {
1322			void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1323
1324			WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1325			continue;
1326		}
1327
1328		hlist_for_each_entry(pol, chain, bydst) {
1329			if (policy->priority >= pol->priority)
1330				newpos = &pol->bydst;
1331			else
1332				break;
1333		}
1334		if (newpos)
1335			hlist_add_behind_rcu(&policy->bydst, newpos);
1336		else
1337			hlist_add_head_rcu(&policy->bydst, chain);
1338	}
1339
1340out_unlock:
1341	__xfrm_policy_inexact_flush(net);
1342	write_seqcount_end(&xfrm_policy_hash_generation);
1343	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1344
1345	mutex_unlock(&hash_resize_mutex);
1346}
1347
1348void xfrm_policy_hash_rebuild(struct net *net)
1349{
1350	schedule_work(&net->xfrm.policy_hthresh.work);
1351}
1352EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1353
1354/* Generate new index... KAME seems to generate them ordered by cost
1355 * of an absolute inpredictability of ordering of rules. This will not pass. */
1356static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1357{
1358	static u32 idx_generator;
1359
1360	for (;;) {
1361		struct hlist_head *list;
1362		struct xfrm_policy *p;
1363		u32 idx;
1364		int found;
1365
1366		if (!index) {
1367			idx = (idx_generator | dir);
1368			idx_generator += 8;
1369		} else {
1370			idx = index;
1371			index = 0;
1372		}
1373
1374		if (idx == 0)
1375			idx = 8;
1376		list = net->xfrm.policy_byidx + idx_hash(net, idx);
1377		found = 0;
1378		hlist_for_each_entry(p, list, byidx) {
1379			if (p->index == idx) {
1380				found = 1;
1381				break;
1382			}
1383		}
1384		if (!found)
1385			return idx;
1386	}
1387}
1388
1389static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1390{
1391	u32 *p1 = (u32 *) s1;
1392	u32 *p2 = (u32 *) s2;
1393	int len = sizeof(struct xfrm_selector) / sizeof(u32);
1394	int i;
1395
1396	for (i = 0; i < len; i++) {
1397		if (p1[i] != p2[i])
1398			return 1;
1399	}
1400
1401	return 0;
1402}
1403
1404static void xfrm_policy_requeue(struct xfrm_policy *old,
1405				struct xfrm_policy *new)
1406{
1407	struct xfrm_policy_queue *pq = &old->polq;
1408	struct sk_buff_head list;
1409
1410	if (skb_queue_empty(&pq->hold_queue))
1411		return;
1412
1413	__skb_queue_head_init(&list);
1414
1415	spin_lock_bh(&pq->hold_queue.lock);
1416	skb_queue_splice_init(&pq->hold_queue, &list);
1417	if (del_timer(&pq->hold_timer))
1418		xfrm_pol_put(old);
1419	spin_unlock_bh(&pq->hold_queue.lock);
1420
1421	pq = &new->polq;
1422
1423	spin_lock_bh(&pq->hold_queue.lock);
1424	skb_queue_splice(&list, &pq->hold_queue);
1425	pq->timeout = XFRM_QUEUE_TMO_MIN;
1426	if (!mod_timer(&pq->hold_timer, jiffies))
1427		xfrm_pol_hold(new);
1428	spin_unlock_bh(&pq->hold_queue.lock);
1429}
1430
1431static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
1432				   struct xfrm_policy *pol)
1433{
1434	u32 mark = policy->mark.v & policy->mark.m;
1435
1436	if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
1437		return true;
1438
1439	if ((mark & pol->mark.m) == pol->mark.v &&
1440	    policy->priority == pol->priority)
1441		return true;
1442
1443	return false;
1444}
1445
1446static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1447{
1448	const struct xfrm_pol_inexact_key *k = data;
1449	u32 a = k->type << 24 | k->dir << 16 | k->family;
1450
1451	return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1452			    seed);
1453}
1454
1455static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1456{
1457	const struct xfrm_pol_inexact_bin *b = data;
1458
1459	return xfrm_pol_bin_key(&b->k, 0, seed);
1460}
1461
1462static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1463			    const void *ptr)
1464{
1465	const struct xfrm_pol_inexact_key *key = arg->key;
1466	const struct xfrm_pol_inexact_bin *b = ptr;
1467	int ret;
1468
1469	if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1470		return -1;
1471
1472	ret = b->k.dir ^ key->dir;
1473	if (ret)
1474		return ret;
1475
1476	ret = b->k.type ^ key->type;
1477	if (ret)
1478		return ret;
1479
1480	ret = b->k.family ^ key->family;
1481	if (ret)
1482		return ret;
1483
1484	return b->k.if_id ^ key->if_id;
1485}
1486
1487static const struct rhashtable_params xfrm_pol_inexact_params = {
1488	.head_offset		= offsetof(struct xfrm_pol_inexact_bin, head),
1489	.hashfn			= xfrm_pol_bin_key,
1490	.obj_hashfn		= xfrm_pol_bin_obj,
1491	.obj_cmpfn		= xfrm_pol_bin_cmp,
1492	.automatic_shrinking	= true,
1493};
1494
1495static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1496					    struct xfrm_policy *policy)
1497{
1498	struct xfrm_policy *pol, *delpol = NULL;
1499	struct hlist_node *newpos = NULL;
1500	int i = 0;
1501
1502	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1503		if (pol->type == policy->type &&
1504		    pol->if_id == policy->if_id &&
1505		    !selector_cmp(&pol->selector, &policy->selector) &&
1506		    xfrm_policy_mark_match(policy, pol) &&
1507		    xfrm_sec_ctx_match(pol->security, policy->security) &&
1508		    !WARN_ON(delpol)) {
1509			delpol = pol;
1510			if (policy->priority > pol->priority)
1511				continue;
1512		} else if (policy->priority >= pol->priority) {
1513			newpos = &pol->bydst_inexact_list;
1514			continue;
1515		}
1516		if (delpol)
1517			break;
1518	}
1519
1520	if (newpos)
1521		hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1522	else
1523		hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1524
1525	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1526		pol->pos = i;
1527		i++;
1528	}
1529}
1530
1531static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1532						   struct xfrm_policy *policy,
1533						   bool excl)
1534{
1535	struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1536
1537	hlist_for_each_entry(pol, chain, bydst) {
1538		if (pol->type == policy->type &&
1539		    pol->if_id == policy->if_id &&
1540		    !selector_cmp(&pol->selector, &policy->selector) &&
1541		    xfrm_policy_mark_match(policy, pol) &&
1542		    xfrm_sec_ctx_match(pol->security, policy->security) &&
1543		    !WARN_ON(delpol)) {
1544			if (excl)
1545				return ERR_PTR(-EEXIST);
1546			delpol = pol;
1547			if (policy->priority > pol->priority)
1548				continue;
1549		} else if (policy->priority >= pol->priority) {
1550			newpos = pol;
1551			continue;
1552		}
1553		if (delpol)
1554			break;
1555	}
1556
1557	if (newpos)
1558		hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1559	else
 
 
 
1560		hlist_add_head_rcu(&policy->bydst, chain);
1561
1562	return delpol;
1563}
1564
1565int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1566{
1567	struct net *net = xp_net(policy);
1568	struct xfrm_policy *delpol;
1569	struct hlist_head *chain;
1570
1571	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1572	chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1573	if (chain)
1574		delpol = xfrm_policy_insert_list(chain, policy, excl);
1575	else
1576		delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1577
1578	if (IS_ERR(delpol)) {
1579		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1580		return PTR_ERR(delpol);
1581	}
1582
1583	__xfrm_policy_link(policy, dir);
1584
1585	/* After previous checking, family can either be AF_INET or AF_INET6 */
1586	if (policy->family == AF_INET)
1587		rt_genid_bump_ipv4(net);
1588	else
1589		rt_genid_bump_ipv6(net);
1590
1591	if (delpol) {
1592		xfrm_policy_requeue(delpol, policy);
1593		__xfrm_policy_unlink(delpol, dir);
1594	}
1595	policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1596	hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1597	policy->curlft.add_time = ktime_get_real_seconds();
1598	policy->curlft.use_time = 0;
1599	if (!mod_timer(&policy->timer, jiffies + HZ))
1600		xfrm_pol_hold(policy);
1601	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1602
1603	if (delpol)
1604		xfrm_policy_kill(delpol);
1605	else if (xfrm_bydst_should_resize(net, dir, NULL))
1606		schedule_work(&net->xfrm.policy_hash_work);
1607
1608	return 0;
1609}
1610EXPORT_SYMBOL(xfrm_policy_insert);
1611
1612static struct xfrm_policy *
1613__xfrm_policy_bysel_ctx(struct hlist_head *chain, u32 mark, u32 if_id,
1614			u8 type, int dir,
1615			struct xfrm_selector *sel,
1616			struct xfrm_sec_ctx *ctx)
1617{
1618	struct xfrm_policy *pol;
1619
1620	if (!chain)
1621		return NULL;
1622
1623	hlist_for_each_entry(pol, chain, bydst) {
1624		if (pol->type == type &&
1625		    pol->if_id == if_id &&
1626		    (mark & pol->mark.m) == pol->mark.v &&
1627		    !selector_cmp(sel, &pol->selector) &&
1628		    xfrm_sec_ctx_match(ctx, pol->security))
1629			return pol;
1630	}
1631
1632	return NULL;
1633}
1634
1635struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u32 if_id,
1636					  u8 type, int dir,
1637					  struct xfrm_selector *sel,
1638					  struct xfrm_sec_ctx *ctx, int delete,
1639					  int *err)
1640{
1641	struct xfrm_pol_inexact_bin *bin = NULL;
1642	struct xfrm_policy *pol, *ret = NULL;
1643	struct hlist_head *chain;
1644
1645	*err = 0;
1646	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1647	chain = policy_hash_bysel(net, sel, sel->family, dir);
1648	if (!chain) {
1649		struct xfrm_pol_inexact_candidates cand;
1650		int i;
1651
1652		bin = xfrm_policy_inexact_lookup(net, type,
1653						 sel->family, dir, if_id);
1654		if (!bin) {
1655			spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1656			return NULL;
1657		}
1658
1659		if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1660							 &sel->saddr,
1661							 &sel->daddr)) {
1662			spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1663			return NULL;
1664		}
1665
1666		pol = NULL;
1667		for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1668			struct xfrm_policy *tmp;
1669
1670			tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1671						      if_id, type, dir,
1672						      sel, ctx);
1673			if (!tmp)
1674				continue;
1675
1676			if (!pol || tmp->pos < pol->pos)
1677				pol = tmp;
1678		}
1679	} else {
1680		pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1681					      sel, ctx);
1682	}
1683
1684	if (pol) {
1685		xfrm_pol_hold(pol);
1686		if (delete) {
1687			*err = security_xfrm_policy_delete(pol->security);
1688			if (*err) {
1689				spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1690				return pol;
1691			}
1692			__xfrm_policy_unlink(pol, dir);
1693		}
1694		ret = pol;
1695	}
1696	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1697
1698	if (ret && delete)
1699		xfrm_policy_kill(ret);
1700	if (bin && delete)
1701		xfrm_policy_inexact_prune_bin(bin);
1702	return ret;
1703}
1704EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1705
1706struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u32 if_id,
1707				     u8 type, int dir, u32 id, int delete,
1708				     int *err)
1709{
1710	struct xfrm_policy *pol, *ret;
1711	struct hlist_head *chain;
1712
1713	*err = -ENOENT;
1714	if (xfrm_policy_id2dir(id) != dir)
1715		return NULL;
1716
1717	*err = 0;
1718	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1719	chain = net->xfrm.policy_byidx + idx_hash(net, id);
1720	ret = NULL;
1721	hlist_for_each_entry(pol, chain, byidx) {
1722		if (pol->type == type && pol->index == id &&
1723		    pol->if_id == if_id &&
1724		    (mark & pol->mark.m) == pol->mark.v) {
1725			xfrm_pol_hold(pol);
1726			if (delete) {
1727				*err = security_xfrm_policy_delete(
1728								pol->security);
1729				if (*err) {
1730					spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1731					return pol;
1732				}
1733				__xfrm_policy_unlink(pol, dir);
1734			}
1735			ret = pol;
1736			break;
1737		}
1738	}
1739	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1740
1741	if (ret && delete)
1742		xfrm_policy_kill(ret);
1743	return ret;
1744}
1745EXPORT_SYMBOL(xfrm_policy_byid);
1746
1747#ifdef CONFIG_SECURITY_NETWORK_XFRM
1748static inline int
1749xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1750{
1751	struct xfrm_policy *pol;
1752	int err = 0;
1753
1754	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1755		if (pol->walk.dead ||
1756		    xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1757		    pol->type != type)
1758			continue;
1759
1760		err = security_xfrm_policy_delete(pol->security);
1761		if (err) {
1762			xfrm_audit_policy_delete(pol, 0, task_valid);
1763			return err;
1764		}
1765	}
1766	return err;
1767}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1768#else
1769static inline int
1770xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1771{
1772	return 0;
1773}
 
 
 
 
 
 
 
1774#endif
1775
1776int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1777{
1778	int dir, err = 0, cnt = 0;
1779	struct xfrm_policy *pol;
1780
1781	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1782
1783	err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1784	if (err)
1785		goto out;
1786
1787again:
1788	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
 
 
 
1789		dir = xfrm_policy_id2dir(pol->index);
1790		if (pol->walk.dead ||
1791		    dir >= XFRM_POLICY_MAX ||
1792		    pol->type != type)
1793			continue;
1794
1795		__xfrm_policy_unlink(pol, dir);
1796		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 
1797		cnt++;
1798		xfrm_audit_policy_delete(pol, 1, task_valid);
1799		xfrm_policy_kill(pol);
1800		spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1801		goto again;
1802	}
1803	if (cnt)
1804		__xfrm_policy_inexact_flush(net);
1805	else
1806		err = -ESRCH;
1807out:
1808	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1809	return err;
1810}
1811EXPORT_SYMBOL(xfrm_policy_flush);
1812
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1813int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1814		     int (*func)(struct xfrm_policy *, int, int, void*),
1815		     void *data)
1816{
1817	struct xfrm_policy *pol;
1818	struct xfrm_policy_walk_entry *x;
1819	int error = 0;
1820
1821	if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1822	    walk->type != XFRM_POLICY_TYPE_ANY)
1823		return -EINVAL;
1824
1825	if (list_empty(&walk->walk.all) && walk->seq != 0)
1826		return 0;
1827
1828	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1829	if (list_empty(&walk->walk.all))
1830		x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1831	else
1832		x = list_first_entry(&walk->walk.all,
1833				     struct xfrm_policy_walk_entry, all);
1834
1835	list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1836		if (x->dead)
1837			continue;
1838		pol = container_of(x, struct xfrm_policy, walk);
1839		if (walk->type != XFRM_POLICY_TYPE_ANY &&
1840		    walk->type != pol->type)
1841			continue;
1842		error = func(pol, xfrm_policy_id2dir(pol->index),
1843			     walk->seq, data);
1844		if (error) {
1845			list_move_tail(&walk->walk.all, &x->all);
1846			goto out;
1847		}
1848		walk->seq++;
1849	}
1850	if (walk->seq == 0) {
1851		error = -ENOENT;
1852		goto out;
1853	}
1854	list_del_init(&walk->walk.all);
1855out:
1856	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1857	return error;
1858}
1859EXPORT_SYMBOL(xfrm_policy_walk);
1860
1861void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1862{
1863	INIT_LIST_HEAD(&walk->walk.all);
1864	walk->walk.dead = 1;
1865	walk->type = type;
1866	walk->seq = 0;
1867}
1868EXPORT_SYMBOL(xfrm_policy_walk_init);
1869
1870void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1871{
1872	if (list_empty(&walk->walk.all))
1873		return;
1874
1875	spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1876	list_del(&walk->walk.all);
1877	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1878}
1879EXPORT_SYMBOL(xfrm_policy_walk_done);
1880
1881/*
1882 * Find policy to apply to this flow.
1883 *
1884 * Returns 0 if policy found, else an -errno.
1885 */
1886static int xfrm_policy_match(const struct xfrm_policy *pol,
1887			     const struct flowi *fl,
1888			     u8 type, u16 family, int dir, u32 if_id)
1889{
1890	const struct xfrm_selector *sel = &pol->selector;
1891	int ret = -ESRCH;
1892	bool match;
1893
1894	if (pol->family != family ||
1895	    pol->if_id != if_id ||
1896	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1897	    pol->type != type)
1898		return ret;
1899
1900	match = xfrm_selector_match(sel, fl, family);
1901	if (match)
1902		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
1903						  dir);
1904	return ret;
1905}
1906
1907static struct xfrm_pol_inexact_node *
1908xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
1909				seqcount_t *count,
1910				const xfrm_address_t *addr, u16 family)
1911{
1912	const struct rb_node *parent;
1913	int seq;
1914
1915again:
1916	seq = read_seqcount_begin(count);
1917
1918	parent = rcu_dereference_raw(r->rb_node);
1919	while (parent) {
1920		struct xfrm_pol_inexact_node *node;
1921		int delta;
1922
1923		node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
1924
1925		delta = xfrm_policy_addr_delta(addr, &node->addr,
1926					       node->prefixlen, family);
1927		if (delta < 0) {
1928			parent = rcu_dereference_raw(parent->rb_left);
1929			continue;
1930		} else if (delta > 0) {
1931			parent = rcu_dereference_raw(parent->rb_right);
1932			continue;
1933		}
1934
1935		return node;
1936	}
1937
1938	if (read_seqcount_retry(count, seq))
1939		goto again;
1940
1941	return NULL;
1942}
1943
1944static bool
1945xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
1946				    struct xfrm_pol_inexact_bin *b,
1947				    const xfrm_address_t *saddr,
1948				    const xfrm_address_t *daddr)
1949{
1950	struct xfrm_pol_inexact_node *n;
1951	u16 family;
1952
1953	if (!b)
1954		return false;
1955
1956	family = b->k.family;
1957	memset(cand, 0, sizeof(*cand));
1958	cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
1959
1960	n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
1961					    family);
1962	if (n) {
1963		cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
1964		n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
1965						    family);
1966		if (n)
1967			cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
1968	}
1969
1970	n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
1971					    family);
1972	if (n)
1973		cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
1974
1975	return true;
1976}
1977
1978static struct xfrm_pol_inexact_bin *
1979xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
1980			       u8 dir, u32 if_id)
1981{
1982	struct xfrm_pol_inexact_key k = {
1983		.family = family,
1984		.type = type,
1985		.dir = dir,
1986		.if_id = if_id,
1987	};
1988
1989	write_pnet(&k.net, net);
1990
1991	return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
1992				 xfrm_pol_inexact_params);
1993}
1994
1995static struct xfrm_pol_inexact_bin *
1996xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
1997			   u8 dir, u32 if_id)
1998{
1999	struct xfrm_pol_inexact_bin *bin;
2000
2001	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2002
2003	rcu_read_lock();
2004	bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2005	rcu_read_unlock();
2006
2007	return bin;
2008}
2009
2010static struct xfrm_policy *
2011__xfrm_policy_eval_candidates(struct hlist_head *chain,
2012			      struct xfrm_policy *prefer,
2013			      const struct flowi *fl,
2014			      u8 type, u16 family, int dir, u32 if_id)
2015{
2016	u32 priority = prefer ? prefer->priority : ~0u;
2017	struct xfrm_policy *pol;
2018
2019	if (!chain)
2020		return NULL;
2021
2022	hlist_for_each_entry_rcu(pol, chain, bydst) {
2023		int err;
2024
2025		if (pol->priority > priority)
2026			break;
2027
2028		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2029		if (err) {
2030			if (err != -ESRCH)
2031				return ERR_PTR(err);
2032
2033			continue;
2034		}
2035
2036		if (prefer) {
2037			/* matches.  Is it older than *prefer? */
2038			if (pol->priority == priority &&
2039			    prefer->pos < pol->pos)
2040				return prefer;
2041		}
2042
2043		return pol;
2044	}
2045
2046	return NULL;
2047}
2048
2049static struct xfrm_policy *
2050xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2051			    struct xfrm_policy *prefer,
2052			    const struct flowi *fl,
2053			    u8 type, u16 family, int dir, u32 if_id)
2054{
2055	struct xfrm_policy *tmp;
2056	int i;
2057
2058	for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2059		tmp = __xfrm_policy_eval_candidates(cand->res[i],
2060						    prefer,
2061						    fl, type, family, dir,
2062						    if_id);
2063		if (!tmp)
2064			continue;
2065
2066		if (IS_ERR(tmp))
2067			return tmp;
2068		prefer = tmp;
2069	}
2070
2071	return prefer;
2072}
2073
2074static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2075						     const struct flowi *fl,
2076						     u16 family, u8 dir,
2077						     u32 if_id)
2078{
2079	struct xfrm_pol_inexact_candidates cand;
2080	const xfrm_address_t *daddr, *saddr;
2081	struct xfrm_pol_inexact_bin *bin;
2082	struct xfrm_policy *pol, *ret;
2083	struct hlist_head *chain;
2084	unsigned int sequence;
2085	int err;
2086
2087	daddr = xfrm_flowi_daddr(fl, family);
2088	saddr = xfrm_flowi_saddr(fl, family);
2089	if (unlikely(!daddr || !saddr))
2090		return NULL;
2091
2092	rcu_read_lock();
2093 retry:
2094	do {
2095		sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
2096		chain = policy_hash_direct(net, daddr, saddr, family, dir);
2097	} while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
2098
2099	ret = NULL;
2100	hlist_for_each_entry_rcu(pol, chain, bydst) {
2101		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
2102		if (err) {
2103			if (err == -ESRCH)
2104				continue;
2105			else {
2106				ret = ERR_PTR(err);
2107				goto fail;
2108			}
2109		} else {
2110			ret = pol;
2111			break;
2112		}
2113	}
 
 
 
2114	bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2115	if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2116							 daddr))
2117		goto skip_inexact;
2118
2119	pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2120					  family, dir, if_id);
2121	if (pol) {
2122		ret = pol;
2123		if (IS_ERR(pol))
2124			goto fail;
2125	}
2126
2127skip_inexact:
2128	if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
2129		goto retry;
2130
2131	if (ret && !xfrm_pol_hold_rcu(ret))
2132		goto retry;
2133fail:
2134	rcu_read_unlock();
2135
2136	return ret;
2137}
2138
2139static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2140					      const struct flowi *fl,
2141					      u16 family, u8 dir, u32 if_id)
2142{
2143#ifdef CONFIG_XFRM_SUB_POLICY
2144	struct xfrm_policy *pol;
2145
2146	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2147					dir, if_id);
2148	if (pol != NULL)
2149		return pol;
2150#endif
2151	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2152					 dir, if_id);
2153}
2154
2155static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2156						 const struct flowi *fl,
2157						 u16 family, u32 if_id)
2158{
2159	struct xfrm_policy *pol;
2160
2161	rcu_read_lock();
2162 again:
2163	pol = rcu_dereference(sk->sk_policy[dir]);
2164	if (pol != NULL) {
2165		bool match;
2166		int err = 0;
2167
2168		if (pol->family != family) {
2169			pol = NULL;
2170			goto out;
2171		}
2172
2173		match = xfrm_selector_match(&pol->selector, fl, family);
2174		if (match) {
2175			if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
2176			    pol->if_id != if_id) {
2177				pol = NULL;
2178				goto out;
2179			}
2180			err = security_xfrm_policy_lookup(pol->security,
2181						      fl->flowi_secid,
2182						      dir);
2183			if (!err) {
2184				if (!xfrm_pol_hold_rcu(pol))
2185					goto again;
2186			} else if (err == -ESRCH) {
2187				pol = NULL;
2188			} else {
2189				pol = ERR_PTR(err);
2190			}
2191		} else
2192			pol = NULL;
2193	}
2194out:
2195	rcu_read_unlock();
2196	return pol;
2197}
2198
2199static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2200{
2201	struct net *net = xp_net(pol);
2202
2203	list_add(&pol->walk.all, &net->xfrm.policy_all);
2204	net->xfrm.policy_count[dir]++;
2205	xfrm_pol_hold(pol);
2206}
2207
2208static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2209						int dir)
2210{
2211	struct net *net = xp_net(pol);
2212
2213	if (list_empty(&pol->walk.all))
2214		return NULL;
2215
2216	/* Socket policies are not hashed. */
2217	if (!hlist_unhashed(&pol->bydst)) {
2218		hlist_del_rcu(&pol->bydst);
2219		hlist_del_init(&pol->bydst_inexact_list);
2220		hlist_del(&pol->byidx);
2221	}
2222
2223	list_del_init(&pol->walk.all);
2224	net->xfrm.policy_count[dir]--;
2225
2226	return pol;
2227}
2228
2229static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2230{
2231	__xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2232}
2233
2234static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2235{
2236	__xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2237}
2238
2239int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2240{
2241	struct net *net = xp_net(pol);
2242
2243	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2244	pol = __xfrm_policy_unlink(pol, dir);
2245	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2246	if (pol) {
 
2247		xfrm_policy_kill(pol);
2248		return 0;
2249	}
2250	return -ENOENT;
2251}
2252EXPORT_SYMBOL(xfrm_policy_delete);
2253
2254int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2255{
2256	struct net *net = sock_net(sk);
2257	struct xfrm_policy *old_pol;
2258
2259#ifdef CONFIG_XFRM_SUB_POLICY
2260	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2261		return -EINVAL;
2262#endif
2263
2264	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2265	old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2266				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2267	if (pol) {
2268		pol->curlft.add_time = ktime_get_real_seconds();
2269		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2270		xfrm_sk_policy_link(pol, dir);
2271	}
2272	rcu_assign_pointer(sk->sk_policy[dir], pol);
2273	if (old_pol) {
2274		if (pol)
2275			xfrm_policy_requeue(old_pol, pol);
2276
2277		/* Unlinking succeeds always. This is the only function
2278		 * allowed to delete or replace socket policy.
2279		 */
2280		xfrm_sk_policy_unlink(old_pol, dir);
2281	}
2282	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2283
2284	if (old_pol) {
2285		xfrm_policy_kill(old_pol);
2286	}
2287	return 0;
2288}
2289
2290static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2291{
2292	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2293	struct net *net = xp_net(old);
2294
2295	if (newp) {
2296		newp->selector = old->selector;
2297		if (security_xfrm_policy_clone(old->security,
2298					       &newp->security)) {
2299			kfree(newp);
2300			return NULL;  /* ENOMEM */
2301		}
2302		newp->lft = old->lft;
2303		newp->curlft = old->curlft;
2304		newp->mark = old->mark;
2305		newp->if_id = old->if_id;
2306		newp->action = old->action;
2307		newp->flags = old->flags;
2308		newp->xfrm_nr = old->xfrm_nr;
2309		newp->index = old->index;
2310		newp->type = old->type;
2311		newp->family = old->family;
2312		memcpy(newp->xfrm_vec, old->xfrm_vec,
2313		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2314		spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2315		xfrm_sk_policy_link(newp, dir);
2316		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2317		xfrm_pol_put(newp);
2318	}
2319	return newp;
2320}
2321
2322int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2323{
2324	const struct xfrm_policy *p;
2325	struct xfrm_policy *np;
2326	int i, ret = 0;
2327
2328	rcu_read_lock();
2329	for (i = 0; i < 2; i++) {
2330		p = rcu_dereference(osk->sk_policy[i]);
2331		if (p) {
2332			np = clone_policy(p, i);
2333			if (unlikely(!np)) {
2334				ret = -ENOMEM;
2335				break;
2336			}
2337			rcu_assign_pointer(sk->sk_policy[i], np);
2338		}
2339	}
2340	rcu_read_unlock();
2341	return ret;
2342}
2343
2344static int
2345xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2346	       xfrm_address_t *remote, unsigned short family, u32 mark)
2347{
2348	int err;
2349	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2350
2351	if (unlikely(afinfo == NULL))
2352		return -EINVAL;
2353	err = afinfo->get_saddr(net, oif, local, remote, mark);
2354	rcu_read_unlock();
2355	return err;
2356}
2357
2358/* Resolve list of templates for the flow, given policy. */
2359
2360static int
2361xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2362		      struct xfrm_state **xfrm, unsigned short family)
2363{
2364	struct net *net = xp_net(policy);
2365	int nx;
2366	int i, error;
2367	xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2368	xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2369	xfrm_address_t tmp;
2370
2371	for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2372		struct xfrm_state *x;
2373		xfrm_address_t *remote = daddr;
2374		xfrm_address_t *local  = saddr;
2375		struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2376
2377		if (tmpl->mode == XFRM_MODE_TUNNEL ||
2378		    tmpl->mode == XFRM_MODE_BEET) {
2379			remote = &tmpl->id.daddr;
2380			local = &tmpl->saddr;
2381			if (xfrm_addr_any(local, tmpl->encap_family)) {
2382				error = xfrm_get_saddr(net, fl->flowi_oif,
2383						       &tmp, remote,
2384						       tmpl->encap_family, 0);
2385				if (error)
2386					goto fail;
2387				local = &tmp;
2388			}
2389		}
2390
2391		x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2392				    family, policy->if_id);
2393
2394		if (x && x->km.state == XFRM_STATE_VALID) {
2395			xfrm[nx++] = x;
2396			daddr = remote;
2397			saddr = local;
2398			continue;
2399		}
2400		if (x) {
2401			error = (x->km.state == XFRM_STATE_ERROR ?
2402				 -EINVAL : -EAGAIN);
2403			xfrm_state_put(x);
2404		} else if (error == -ESRCH) {
2405			error = -EAGAIN;
2406		}
2407
2408		if (!tmpl->optional)
2409			goto fail;
2410	}
2411	return nx;
2412
2413fail:
2414	for (nx--; nx >= 0; nx--)
2415		xfrm_state_put(xfrm[nx]);
2416	return error;
2417}
2418
2419static int
2420xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2421		  struct xfrm_state **xfrm, unsigned short family)
2422{
2423	struct xfrm_state *tp[XFRM_MAX_DEPTH];
2424	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2425	int cnx = 0;
2426	int error;
2427	int ret;
2428	int i;
2429
2430	for (i = 0; i < npols; i++) {
2431		if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2432			error = -ENOBUFS;
2433			goto fail;
2434		}
2435
2436		ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2437		if (ret < 0) {
2438			error = ret;
2439			goto fail;
2440		} else
2441			cnx += ret;
2442	}
2443
2444	/* found states are sorted for outbound processing */
2445	if (npols > 1)
2446		xfrm_state_sort(xfrm, tpp, cnx, family);
2447
2448	return cnx;
2449
2450 fail:
2451	for (cnx--; cnx >= 0; cnx--)
2452		xfrm_state_put(tpp[cnx]);
2453	return error;
2454
2455}
2456
2457static int xfrm_get_tos(const struct flowi *fl, int family)
2458{
2459	if (family == AF_INET)
2460		return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2461
2462	return 0;
2463}
2464
2465static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2466{
2467	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2468	struct dst_ops *dst_ops;
2469	struct xfrm_dst *xdst;
2470
2471	if (!afinfo)
2472		return ERR_PTR(-EINVAL);
2473
2474	switch (family) {
2475	case AF_INET:
2476		dst_ops = &net->xfrm.xfrm4_dst_ops;
2477		break;
2478#if IS_ENABLED(CONFIG_IPV6)
2479	case AF_INET6:
2480		dst_ops = &net->xfrm.xfrm6_dst_ops;
2481		break;
2482#endif
2483	default:
2484		BUG();
2485	}
2486	xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2487
2488	if (likely(xdst)) {
2489		struct dst_entry *dst = &xdst->u.dst;
2490
2491		memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
2492	} else
2493		xdst = ERR_PTR(-ENOBUFS);
2494
2495	rcu_read_unlock();
2496
2497	return xdst;
2498}
2499
2500static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2501			   int nfheader_len)
2502{
2503	if (dst->ops->family == AF_INET6) {
2504		struct rt6_info *rt = (struct rt6_info *)dst;
2505		path->path_cookie = rt6_get_cookie(rt);
2506		path->u.rt6.rt6i_nfheader_len = nfheader_len;
2507	}
2508}
2509
2510static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2511				const struct flowi *fl)
2512{
2513	const struct xfrm_policy_afinfo *afinfo =
2514		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2515	int err;
2516
2517	if (!afinfo)
2518		return -EINVAL;
2519
2520	err = afinfo->fill_dst(xdst, dev, fl);
2521
2522	rcu_read_unlock();
2523
2524	return err;
2525}
2526
2527
2528/* Allocate chain of dst_entry's, attach known xfrm's, calculate
2529 * all the metrics... Shortly, bundle a bundle.
2530 */
2531
2532static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2533					    struct xfrm_state **xfrm,
2534					    struct xfrm_dst **bundle,
2535					    int nx,
2536					    const struct flowi *fl,
2537					    struct dst_entry *dst)
2538{
2539	const struct xfrm_state_afinfo *afinfo;
2540	const struct xfrm_mode *inner_mode;
2541	struct net *net = xp_net(policy);
2542	unsigned long now = jiffies;
2543	struct net_device *dev;
2544	struct xfrm_dst *xdst_prev = NULL;
2545	struct xfrm_dst *xdst0 = NULL;
2546	int i = 0;
2547	int err;
2548	int header_len = 0;
2549	int nfheader_len = 0;
2550	int trailer_len = 0;
2551	int tos;
2552	int family = policy->selector.family;
2553	xfrm_address_t saddr, daddr;
2554
2555	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2556
2557	tos = xfrm_get_tos(fl, family);
2558
2559	dst_hold(dst);
2560
2561	for (; i < nx; i++) {
2562		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2563		struct dst_entry *dst1 = &xdst->u.dst;
2564
2565		err = PTR_ERR(xdst);
2566		if (IS_ERR(xdst)) {
2567			dst_release(dst);
2568			goto put_states;
2569		}
2570
2571		bundle[i] = xdst;
2572		if (!xdst_prev)
2573			xdst0 = xdst;
2574		else
2575			/* Ref count is taken during xfrm_alloc_dst()
2576			 * No need to do dst_clone() on dst1
2577			 */
2578			xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2579
2580		if (xfrm[i]->sel.family == AF_UNSPEC) {
2581			inner_mode = xfrm_ip2inner_mode(xfrm[i],
2582							xfrm_af2proto(family));
2583			if (!inner_mode) {
2584				err = -EAFNOSUPPORT;
2585				dst_release(dst);
2586				goto put_states;
2587			}
2588		} else
2589			inner_mode = &xfrm[i]->inner_mode;
2590
2591		xdst->route = dst;
2592		dst_copy_metrics(dst1, dst);
2593
2594		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2595			__u32 mark = 0;
 
2596
2597			if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2598				mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2599
2600			family = xfrm[i]->props.family;
2601			dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,
 
 
 
2602					      &saddr, &daddr, family, mark);
2603			err = PTR_ERR(dst);
2604			if (IS_ERR(dst))
2605				goto put_states;
2606		} else
2607			dst_hold(dst);
2608
2609		dst1->xfrm = xfrm[i];
2610		xdst->xfrm_genid = xfrm[i]->genid;
2611
2612		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2613		dst1->flags |= DST_HOST;
2614		dst1->lastuse = now;
2615
2616		dst1->input = dst_discard;
2617
2618		rcu_read_lock();
2619		afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2620		if (likely(afinfo))
2621			dst1->output = afinfo->output;
2622		else
2623			dst1->output = dst_discard_out;
2624		rcu_read_unlock();
2625
2626		xdst_prev = xdst;
2627
2628		header_len += xfrm[i]->props.header_len;
2629		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2630			nfheader_len += xfrm[i]->props.header_len;
2631		trailer_len += xfrm[i]->props.trailer_len;
2632	}
2633
2634	xfrm_dst_set_child(xdst_prev, dst);
2635	xdst0->path = dst;
2636
2637	err = -ENODEV;
2638	dev = dst->dev;
2639	if (!dev)
2640		goto free_dst;
2641
2642	xfrm_init_path(xdst0, dst, nfheader_len);
2643	xfrm_init_pmtu(bundle, nx);
2644
2645	for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2646	     xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2647		err = xfrm_fill_dst(xdst_prev, dev, fl);
2648		if (err)
2649			goto free_dst;
2650
2651		xdst_prev->u.dst.header_len = header_len;
2652		xdst_prev->u.dst.trailer_len = trailer_len;
2653		header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2654		trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2655	}
2656
2657	return &xdst0->u.dst;
2658
2659put_states:
2660	for (; i < nx; i++)
2661		xfrm_state_put(xfrm[i]);
2662free_dst:
2663	if (xdst0)
2664		dst_release_immediate(&xdst0->u.dst);
2665
2666	return ERR_PTR(err);
2667}
2668
2669static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2670				struct xfrm_policy **pols,
2671				int *num_pols, int *num_xfrms)
2672{
2673	int i;
2674
2675	if (*num_pols == 0 || !pols[0]) {
2676		*num_pols = 0;
2677		*num_xfrms = 0;
2678		return 0;
2679	}
2680	if (IS_ERR(pols[0]))
 
2681		return PTR_ERR(pols[0]);
 
2682
2683	*num_xfrms = pols[0]->xfrm_nr;
2684
2685#ifdef CONFIG_XFRM_SUB_POLICY
2686	if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
2687	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2688		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2689						    XFRM_POLICY_TYPE_MAIN,
2690						    fl, family,
2691						    XFRM_POLICY_OUT,
2692						    pols[0]->if_id);
2693		if (pols[1]) {
2694			if (IS_ERR(pols[1])) {
2695				xfrm_pols_put(pols, *num_pols);
 
2696				return PTR_ERR(pols[1]);
2697			}
2698			(*num_pols)++;
2699			(*num_xfrms) += pols[1]->xfrm_nr;
2700		}
2701	}
2702#endif
2703	for (i = 0; i < *num_pols; i++) {
2704		if (pols[i]->action != XFRM_POLICY_ALLOW) {
2705			*num_xfrms = -1;
2706			break;
2707		}
2708	}
2709
2710	return 0;
2711
2712}
2713
2714static struct xfrm_dst *
2715xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2716			       const struct flowi *fl, u16 family,
2717			       struct dst_entry *dst_orig)
2718{
2719	struct net *net = xp_net(pols[0]);
2720	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2721	struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2722	struct xfrm_dst *xdst;
2723	struct dst_entry *dst;
2724	int err;
2725
2726	/* Try to instantiate a bundle */
2727	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2728	if (err <= 0) {
2729		if (err == 0)
2730			return NULL;
2731
2732		if (err != -EAGAIN)
2733			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2734		return ERR_PTR(err);
2735	}
2736
2737	dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2738	if (IS_ERR(dst)) {
2739		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2740		return ERR_CAST(dst);
2741	}
2742
2743	xdst = (struct xfrm_dst *)dst;
2744	xdst->num_xfrms = err;
2745	xdst->num_pols = num_pols;
2746	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2747	xdst->policy_genid = atomic_read(&pols[0]->genid);
2748
2749	return xdst;
2750}
2751
2752static void xfrm_policy_queue_process(struct timer_list *t)
2753{
2754	struct sk_buff *skb;
2755	struct sock *sk;
2756	struct dst_entry *dst;
2757	struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2758	struct net *net = xp_net(pol);
2759	struct xfrm_policy_queue *pq = &pol->polq;
2760	struct flowi fl;
2761	struct sk_buff_head list;
 
2762
2763	spin_lock(&pq->hold_queue.lock);
2764	skb = skb_peek(&pq->hold_queue);
2765	if (!skb) {
2766		spin_unlock(&pq->hold_queue.lock);
2767		goto out;
2768	}
2769	dst = skb_dst(skb);
2770	sk = skb->sk;
2771	xfrm_decode_session(skb, &fl, dst->ops->family);
 
 
 
 
 
2772	spin_unlock(&pq->hold_queue.lock);
2773
2774	dst_hold(xfrm_dst_path(dst));
2775	dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2776	if (IS_ERR(dst))
2777		goto purge_queue;
2778
2779	if (dst->flags & DST_XFRM_QUEUE) {
2780		dst_release(dst);
2781
2782		if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2783			goto purge_queue;
2784
2785		pq->timeout = pq->timeout << 1;
2786		if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2787			xfrm_pol_hold(pol);
2788		goto out;
2789	}
2790
2791	dst_release(dst);
2792
2793	__skb_queue_head_init(&list);
2794
2795	spin_lock(&pq->hold_queue.lock);
2796	pq->timeout = 0;
2797	skb_queue_splice_init(&pq->hold_queue, &list);
2798	spin_unlock(&pq->hold_queue.lock);
2799
2800	while (!skb_queue_empty(&list)) {
2801		skb = __skb_dequeue(&list);
2802
2803		xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
 
 
 
 
 
2804		dst_hold(xfrm_dst_path(skb_dst(skb)));
2805		dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2806		if (IS_ERR(dst)) {
2807			kfree_skb(skb);
2808			continue;
2809		}
2810
2811		nf_reset_ct(skb);
2812		skb_dst_drop(skb);
2813		skb_dst_set(skb, dst);
2814
2815		dst_output(net, skb->sk, skb);
2816	}
2817
2818out:
2819	xfrm_pol_put(pol);
2820	return;
2821
2822purge_queue:
2823	pq->timeout = 0;
2824	skb_queue_purge(&pq->hold_queue);
2825	xfrm_pol_put(pol);
2826}
2827
2828static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2829{
2830	unsigned long sched_next;
2831	struct dst_entry *dst = skb_dst(skb);
2832	struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2833	struct xfrm_policy *pol = xdst->pols[0];
2834	struct xfrm_policy_queue *pq = &pol->polq;
2835
2836	if (unlikely(skb_fclone_busy(sk, skb))) {
2837		kfree_skb(skb);
2838		return 0;
2839	}
2840
2841	if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2842		kfree_skb(skb);
2843		return -EAGAIN;
2844	}
2845
2846	skb_dst_force(skb);
2847
2848	spin_lock_bh(&pq->hold_queue.lock);
2849
2850	if (!pq->timeout)
2851		pq->timeout = XFRM_QUEUE_TMO_MIN;
2852
2853	sched_next = jiffies + pq->timeout;
2854
2855	if (del_timer(&pq->hold_timer)) {
2856		if (time_before(pq->hold_timer.expires, sched_next))
2857			sched_next = pq->hold_timer.expires;
2858		xfrm_pol_put(pol);
2859	}
2860
2861	__skb_queue_tail(&pq->hold_queue, skb);
2862	if (!mod_timer(&pq->hold_timer, sched_next))
2863		xfrm_pol_hold(pol);
2864
2865	spin_unlock_bh(&pq->hold_queue.lock);
2866
2867	return 0;
2868}
2869
2870static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2871						 struct xfrm_flo *xflo,
2872						 const struct flowi *fl,
2873						 int num_xfrms,
2874						 u16 family)
2875{
2876	int err;
2877	struct net_device *dev;
2878	struct dst_entry *dst;
2879	struct dst_entry *dst1;
2880	struct xfrm_dst *xdst;
2881
2882	xdst = xfrm_alloc_dst(net, family);
2883	if (IS_ERR(xdst))
2884		return xdst;
2885
2886	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
2887	    net->xfrm.sysctl_larval_drop ||
2888	    num_xfrms <= 0)
2889		return xdst;
2890
2891	dst = xflo->dst_orig;
2892	dst1 = &xdst->u.dst;
2893	dst_hold(dst);
2894	xdst->route = dst;
2895
2896	dst_copy_metrics(dst1, dst);
2897
2898	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
2899	dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
2900	dst1->lastuse = jiffies;
2901
2902	dst1->input = dst_discard;
2903	dst1->output = xdst_queue_output;
2904
2905	dst_hold(dst);
2906	xfrm_dst_set_child(xdst, dst);
2907	xdst->path = dst;
2908
2909	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
2910
2911	err = -ENODEV;
2912	dev = dst->dev;
2913	if (!dev)
2914		goto free_dst;
2915
2916	err = xfrm_fill_dst(xdst, dev, fl);
2917	if (err)
2918		goto free_dst;
2919
2920out:
2921	return xdst;
2922
2923free_dst:
2924	dst_release(dst1);
2925	xdst = ERR_PTR(err);
2926	goto out;
2927}
2928
2929static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
2930					   const struct flowi *fl,
2931					   u16 family, u8 dir,
2932					   struct xfrm_flo *xflo, u32 if_id)
2933{
2934	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
2935	int num_pols = 0, num_xfrms = 0, err;
2936	struct xfrm_dst *xdst;
2937
2938	/* Resolve policies to use if we couldn't get them from
2939	 * previous cache entry */
2940	num_pols = 1;
2941	pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
2942	err = xfrm_expand_policies(fl, family, pols,
2943					   &num_pols, &num_xfrms);
2944	if (err < 0)
2945		goto inc_error;
2946	if (num_pols == 0)
2947		return NULL;
2948	if (num_xfrms <= 0)
2949		goto make_dummy_bundle;
2950
2951	xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
2952					      xflo->dst_orig);
2953	if (IS_ERR(xdst)) {
2954		err = PTR_ERR(xdst);
2955		if (err == -EREMOTE) {
2956			xfrm_pols_put(pols, num_pols);
2957			return NULL;
2958		}
2959
2960		if (err != -EAGAIN)
2961			goto error;
2962		goto make_dummy_bundle;
2963	} else if (xdst == NULL) {
2964		num_xfrms = 0;
2965		goto make_dummy_bundle;
2966	}
2967
2968	return xdst;
2969
2970make_dummy_bundle:
2971	/* We found policies, but there's no bundles to instantiate:
2972	 * either because the policy blocks, has no transformations or
2973	 * we could not build template (no xfrm_states).*/
2974	xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
2975	if (IS_ERR(xdst)) {
2976		xfrm_pols_put(pols, num_pols);
2977		return ERR_CAST(xdst);
2978	}
2979	xdst->num_pols = num_pols;
2980	xdst->num_xfrms = num_xfrms;
2981	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2982
2983	return xdst;
2984
2985inc_error:
2986	XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2987error:
2988	xfrm_pols_put(pols, num_pols);
2989	return ERR_PTR(err);
2990}
2991
2992static struct dst_entry *make_blackhole(struct net *net, u16 family,
2993					struct dst_entry *dst_orig)
2994{
2995	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2996	struct dst_entry *ret;
2997
2998	if (!afinfo) {
2999		dst_release(dst_orig);
3000		return ERR_PTR(-EINVAL);
3001	} else {
3002		ret = afinfo->blackhole_route(net, dst_orig);
3003	}
3004	rcu_read_unlock();
3005
3006	return ret;
3007}
3008
3009/* Finds/creates a bundle for given flow and if_id
3010 *
3011 * At the moment we eat a raw IP route. Mostly to speed up lookups
3012 * on interfaces with disabled IPsec.
3013 *
3014 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3015 * compatibility
3016 */
3017struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3018					struct dst_entry *dst_orig,
3019					const struct flowi *fl,
3020					const struct sock *sk,
3021					int flags, u32 if_id)
3022{
3023	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3024	struct xfrm_dst *xdst;
3025	struct dst_entry *dst, *route;
3026	u16 family = dst_orig->ops->family;
3027	u8 dir = XFRM_POLICY_OUT;
3028	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3029
3030	dst = NULL;
3031	xdst = NULL;
3032	route = NULL;
3033
3034	sk = sk_const_to_full_sk(sk);
3035	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3036		num_pols = 1;
3037		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3038						if_id);
3039		err = xfrm_expand_policies(fl, family, pols,
3040					   &num_pols, &num_xfrms);
3041		if (err < 0)
3042			goto dropdst;
3043
3044		if (num_pols) {
3045			if (num_xfrms <= 0) {
3046				drop_pols = num_pols;
3047				goto no_transform;
3048			}
3049
3050			xdst = xfrm_resolve_and_create_bundle(
3051					pols, num_pols, fl,
3052					family, dst_orig);
3053
3054			if (IS_ERR(xdst)) {
3055				xfrm_pols_put(pols, num_pols);
3056				err = PTR_ERR(xdst);
3057				if (err == -EREMOTE)
3058					goto nopol;
3059
3060				goto dropdst;
3061			} else if (xdst == NULL) {
3062				num_xfrms = 0;
3063				drop_pols = num_pols;
3064				goto no_transform;
3065			}
3066
3067			route = xdst->route;
3068		}
3069	}
3070
3071	if (xdst == NULL) {
3072		struct xfrm_flo xflo;
3073
3074		xflo.dst_orig = dst_orig;
3075		xflo.flags = flags;
3076
3077		/* To accelerate a bit...  */
3078		if ((dst_orig->flags & DST_NOXFRM) ||
3079		    !net->xfrm.policy_count[XFRM_POLICY_OUT])
3080			goto nopol;
3081
3082		xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3083		if (xdst == NULL)
3084			goto nopol;
3085		if (IS_ERR(xdst)) {
3086			err = PTR_ERR(xdst);
3087			goto dropdst;
3088		}
3089
3090		num_pols = xdst->num_pols;
3091		num_xfrms = xdst->num_xfrms;
3092		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3093		route = xdst->route;
3094	}
3095
3096	dst = &xdst->u.dst;
3097	if (route == NULL && num_xfrms > 0) {
3098		/* The only case when xfrm_bundle_lookup() returns a
3099		 * bundle with null route, is when the template could
3100		 * not be resolved. It means policies are there, but
3101		 * bundle could not be created, since we don't yet
3102		 * have the xfrm_state's. We need to wait for KM to
3103		 * negotiate new SA's or bail out with error.*/
3104		if (net->xfrm.sysctl_larval_drop) {
3105			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3106			err = -EREMOTE;
3107			goto error;
3108		}
3109
3110		err = -EAGAIN;
3111
3112		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3113		goto error;
3114	}
3115
3116no_transform:
3117	if (num_pols == 0)
3118		goto nopol;
3119
3120	if ((flags & XFRM_LOOKUP_ICMP) &&
3121	    !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3122		err = -ENOENT;
3123		goto error;
3124	}
3125
3126	for (i = 0; i < num_pols; i++)
3127		pols[i]->curlft.use_time = ktime_get_real_seconds();
3128
3129	if (num_xfrms < 0) {
3130		/* Prohibit the flow */
3131		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3132		err = -EPERM;
3133		goto error;
3134	} else if (num_xfrms > 0) {
3135		/* Flow transformed */
3136		dst_release(dst_orig);
3137	} else {
3138		/* Flow passes untransformed */
3139		dst_release(dst);
3140		dst = dst_orig;
3141	}
3142ok:
3143	xfrm_pols_put(pols, drop_pols);
3144	if (dst && dst->xfrm &&
3145	    dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3146		dst->flags |= DST_XFRM_TUNNEL;
3147	return dst;
3148
3149nopol:
 
 
 
 
 
3150	if (!(flags & XFRM_LOOKUP_ICMP)) {
3151		dst = dst_orig;
3152		goto ok;
3153	}
3154	err = -ENOENT;
3155error:
3156	dst_release(dst);
3157dropdst:
3158	if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3159		dst_release(dst_orig);
3160	xfrm_pols_put(pols, drop_pols);
3161	return ERR_PTR(err);
3162}
3163EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3164
3165/* Main function: finds/creates a bundle for given flow.
3166 *
3167 * At the moment we eat a raw IP route. Mostly to speed up lookups
3168 * on interfaces with disabled IPsec.
3169 */
3170struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3171			      const struct flowi *fl, const struct sock *sk,
3172			      int flags)
3173{
3174	return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3175}
3176EXPORT_SYMBOL(xfrm_lookup);
3177
3178/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3179 * Otherwise we may send out blackholed packets.
3180 */
3181struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3182				    const struct flowi *fl,
3183				    const struct sock *sk, int flags)
3184{
3185	struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3186					    flags | XFRM_LOOKUP_QUEUE |
3187					    XFRM_LOOKUP_KEEP_DST_REF);
3188
3189	if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
3190		return make_blackhole(net, dst_orig->ops->family, dst_orig);
3191
3192	if (IS_ERR(dst))
3193		dst_release(dst_orig);
3194
3195	return dst;
3196}
3197EXPORT_SYMBOL(xfrm_lookup_route);
3198
3199static inline int
3200xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3201{
3202	struct sec_path *sp = skb_sec_path(skb);
3203	struct xfrm_state *x;
3204
3205	if (!sp || idx < 0 || idx >= sp->len)
3206		return 0;
3207	x = sp->xvec[idx];
3208	if (!x->type->reject)
3209		return 0;
3210	return x->type->reject(x, skb, fl);
3211}
3212
3213/* When skb is transformed back to its "native" form, we have to
3214 * check policy restrictions. At the moment we make this in maximally
3215 * stupid way. Shame on me. :-) Of course, connected sockets must
3216 * have policy cached at them.
3217 */
3218
3219static inline int
3220xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3221	      unsigned short family)
3222{
3223	if (xfrm_state_kern(x))
3224		return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3225	return	x->id.proto == tmpl->id.proto &&
3226		(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3227		(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3228		x->props.mode == tmpl->mode &&
3229		(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3230		 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3231		!(x->props.mode != XFRM_MODE_TRANSPORT &&
3232		  xfrm_state_addr_cmp(tmpl, x, family));
 
3233}
3234
3235/*
3236 * 0 or more than 0 is returned when validation is succeeded (either bypass
3237 * because of optional transport mode, or next index of the mathced secpath
3238 * state with the template.
3239 * -1 is returned when no matching template is found.
3240 * Otherwise "-2 - errored_index" is returned.
3241 */
3242static inline int
3243xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3244	       unsigned short family)
3245{
3246	int idx = start;
3247
3248	if (tmpl->optional) {
3249		if (tmpl->mode == XFRM_MODE_TRANSPORT)
3250			return start;
3251	} else
3252		start = -1;
3253	for (; idx < sp->len; idx++) {
3254		if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
3255			return ++idx;
3256		if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
 
 
 
 
 
 
 
3257			if (start == -1)
3258				start = -2-idx;
3259			break;
3260		}
3261	}
3262	return start;
3263}
3264
3265static void
3266decode_session4(struct sk_buff *skb, struct flowi *fl, bool reverse)
3267{
3268	const struct iphdr *iph = ip_hdr(skb);
3269	int ihl = iph->ihl;
3270	u8 *xprth = skb_network_header(skb) + ihl * 4;
3271	struct flowi4 *fl4 = &fl->u.ip4;
3272	int oif = 0;
3273
3274	if (skb_dst(skb) && skb_dst(skb)->dev)
3275		oif = skb_dst(skb)->dev->ifindex;
3276
3277	memset(fl4, 0, sizeof(struct flowi4));
3278	fl4->flowi4_mark = skb->mark;
3279	fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
3280
3281	fl4->flowi4_proto = iph->protocol;
3282	fl4->daddr = reverse ? iph->saddr : iph->daddr;
3283	fl4->saddr = reverse ? iph->daddr : iph->saddr;
3284	fl4->flowi4_tos = iph->tos;
3285
3286	if (!ip_is_fragment(iph)) {
3287		switch (iph->protocol) {
3288		case IPPROTO_UDP:
3289		case IPPROTO_UDPLITE:
3290		case IPPROTO_TCP:
3291		case IPPROTO_SCTP:
3292		case IPPROTO_DCCP:
3293			if (xprth + 4 < skb->data ||
3294			    pskb_may_pull(skb, xprth + 4 - skb->data)) {
3295				__be16 *ports;
3296
3297				xprth = skb_network_header(skb) + ihl * 4;
3298				ports = (__be16 *)xprth;
3299
3300				fl4->fl4_sport = ports[!!reverse];
3301				fl4->fl4_dport = ports[!reverse];
3302			}
3303			break;
3304		case IPPROTO_ICMP:
3305			if (xprth + 2 < skb->data ||
3306			    pskb_may_pull(skb, xprth + 2 - skb->data)) {
3307				u8 *icmp;
3308
3309				xprth = skb_network_header(skb) + ihl * 4;
3310				icmp = xprth;
3311
3312				fl4->fl4_icmp_type = icmp[0];
3313				fl4->fl4_icmp_code = icmp[1];
3314			}
3315			break;
3316		case IPPROTO_ESP:
3317			if (xprth + 4 < skb->data ||
3318			    pskb_may_pull(skb, xprth + 4 - skb->data)) {
3319				__be32 *ehdr;
3320
3321				xprth = skb_network_header(skb) + ihl * 4;
3322				ehdr = (__be32 *)xprth;
3323
3324				fl4->fl4_ipsec_spi = ehdr[0];
3325			}
3326			break;
3327		case IPPROTO_AH:
3328			if (xprth + 8 < skb->data ||
3329			    pskb_may_pull(skb, xprth + 8 - skb->data)) {
3330				__be32 *ah_hdr;
3331
3332				xprth = skb_network_header(skb) + ihl * 4;
3333				ah_hdr = (__be32 *)xprth;
3334
3335				fl4->fl4_ipsec_spi = ah_hdr[1];
3336			}
3337			break;
3338		case IPPROTO_COMP:
3339			if (xprth + 4 < skb->data ||
3340			    pskb_may_pull(skb, xprth + 4 - skb->data)) {
3341				__be16 *ipcomp_hdr;
3342
3343				xprth = skb_network_header(skb) + ihl * 4;
3344				ipcomp_hdr = (__be16 *)xprth;
 
 
 
 
 
 
 
 
 
3345
3346				fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
3347			}
3348			break;
3349		case IPPROTO_GRE:
3350			if (xprth + 12 < skb->data ||
3351			    pskb_may_pull(skb, xprth + 12 - skb->data)) {
3352				__be16 *greflags;
3353				__be32 *gre_hdr;
3354
3355				xprth = skb_network_header(skb) + ihl * 4;
3356				greflags = (__be16 *)xprth;
3357				gre_hdr = (__be32 *)xprth;
3358
3359				if (greflags[0] & GRE_KEY) {
3360					if (greflags[0] & GRE_CSUM)
3361						gre_hdr++;
3362					fl4->fl4_gre_key = gre_hdr[1];
3363				}
3364			}
3365			break;
3366		default:
3367			fl4->fl4_ipsec_spi = 0;
3368			break;
3369		}
3370	}
 
 
 
3371}
3372
3373#if IS_ENABLED(CONFIG_IPV6)
3374static void
3375decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse)
3376{
3377	struct flowi6 *fl6 = &fl->u.ip6;
3378	int onlyproto = 0;
3379	const struct ipv6hdr *hdr = ipv6_hdr(skb);
3380	u32 offset = sizeof(*hdr);
3381	struct ipv6_opt_hdr *exthdr;
3382	const unsigned char *nh = skb_network_header(skb);
3383	u16 nhoff = IP6CB(skb)->nhoff;
3384	int oif = 0;
3385	u8 nexthdr;
3386
3387	if (!nhoff)
3388		nhoff = offsetof(struct ipv6hdr, nexthdr);
3389
3390	nexthdr = nh[nhoff];
3391
3392	if (skb_dst(skb) && skb_dst(skb)->dev)
3393		oif = skb_dst(skb)->dev->ifindex;
3394
3395	memset(fl6, 0, sizeof(struct flowi6));
3396	fl6->flowi6_mark = skb->mark;
3397	fl6->flowi6_oif = reverse ? skb->skb_iif : oif;
3398
3399	fl6->daddr = reverse ? hdr->saddr : hdr->daddr;
3400	fl6->saddr = reverse ? hdr->daddr : hdr->saddr;
 
 
 
 
 
 
 
 
 
3401
3402	while (nh + offset + sizeof(*exthdr) < skb->data ||
3403	       pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) {
3404		nh = skb_network_header(skb);
3405		exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3406
3407		switch (nexthdr) {
3408		case NEXTHDR_FRAGMENT:
3409			onlyproto = 1;
3410			/* fall through */
3411		case NEXTHDR_ROUTING:
3412		case NEXTHDR_HOP:
3413		case NEXTHDR_DEST:
3414			offset += ipv6_optlen(exthdr);
3415			nexthdr = exthdr->nexthdr;
3416			exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3417			break;
3418		case IPPROTO_UDP:
3419		case IPPROTO_UDPLITE:
3420		case IPPROTO_TCP:
3421		case IPPROTO_SCTP:
3422		case IPPROTO_DCCP:
3423			if (!onlyproto && (nh + offset + 4 < skb->data ||
3424			     pskb_may_pull(skb, nh + offset + 4 - skb->data))) {
3425				__be16 *ports;
3426
3427				nh = skb_network_header(skb);
3428				ports = (__be16 *)(nh + offset);
3429				fl6->fl6_sport = ports[!!reverse];
3430				fl6->fl6_dport = ports[!reverse];
3431			}
3432			fl6->flowi6_proto = nexthdr;
3433			return;
3434		case IPPROTO_ICMPV6:
3435			if (!onlyproto && (nh + offset + 2 < skb->data ||
3436			    pskb_may_pull(skb, nh + offset + 2 - skb->data))) {
3437				u8 *icmp;
3438
3439				nh = skb_network_header(skb);
3440				icmp = (u8 *)(nh + offset);
3441				fl6->fl6_icmp_type = icmp[0];
3442				fl6->fl6_icmp_code = icmp[1];
3443			}
3444			fl6->flowi6_proto = nexthdr;
3445			return;
3446#if IS_ENABLED(CONFIG_IPV6_MIP6)
3447		case IPPROTO_MH:
3448			offset += ipv6_optlen(exthdr);
3449			if (!onlyproto && (nh + offset + 3 < skb->data ||
3450			    pskb_may_pull(skb, nh + offset + 3 - skb->data))) {
3451				struct ip6_mh *mh;
3452
3453				nh = skb_network_header(skb);
3454				mh = (struct ip6_mh *)(nh + offset);
3455				fl6->fl6_mh_type = mh->ip6mh_type;
3456			}
3457			fl6->flowi6_proto = nexthdr;
3458			return;
3459#endif
3460		/* XXX Why are there these headers? */
3461		case IPPROTO_AH:
3462		case IPPROTO_ESP:
3463		case IPPROTO_COMP:
3464		default:
3465			fl6->fl6_ipsec_spi = 0;
3466			fl6->flowi6_proto = nexthdr;
3467			return;
3468		}
3469	}
 
 
3470}
3471#endif
3472
3473int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
3474			  unsigned int family, int reverse)
3475{
 
 
 
 
 
 
3476	switch (family) {
3477	case AF_INET:
3478		decode_session4(skb, fl, reverse);
3479		break;
3480#if IS_ENABLED(CONFIG_IPV6)
3481	case AF_INET6:
3482		decode_session6(skb, fl, reverse);
3483		break;
3484#endif
3485	default:
3486		return -EAFNOSUPPORT;
3487	}
3488
 
 
 
 
 
 
 
 
 
 
 
 
3489	return security_xfrm_decode_session(skb, &fl->flowi_secid);
3490}
3491EXPORT_SYMBOL(__xfrm_decode_session);
3492
3493static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3494{
3495	for (; k < sp->len; k++) {
3496		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3497			*idxp = k;
3498			return 1;
3499		}
3500	}
3501
3502	return 0;
3503}
3504
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3505int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3506			unsigned short family)
3507{
3508	struct net *net = dev_net(skb->dev);
3509	struct xfrm_policy *pol;
3510	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3511	int npols = 0;
3512	int xfrm_nr;
3513	int pi;
3514	int reverse;
3515	struct flowi fl;
3516	int xerr_idx = -1;
3517	const struct xfrm_if_cb *ifcb;
3518	struct sec_path *sp;
3519	struct xfrm_if *xi;
3520	u32 if_id = 0;
3521
3522	rcu_read_lock();
3523	ifcb = xfrm_if_get_cb();
3524
3525	if (ifcb) {
3526		xi = ifcb->decode_session(skb, family);
3527		if (xi) {
3528			if_id = xi->p.if_id;
3529			net = xi->net;
 
3530		}
3531	}
3532	rcu_read_unlock();
3533
3534	reverse = dir & ~XFRM_POLICY_MASK;
3535	dir &= XFRM_POLICY_MASK;
3536
3537	if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
3538		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3539		return 0;
3540	}
3541
3542	nf_nat_decode_session(skb, &fl, family);
3543
3544	/* First, check used SA against their selectors. */
3545	sp = skb_sec_path(skb);
3546	if (sp) {
3547		int i;
3548
3549		for (i = sp->len - 1; i >= 0; i--) {
3550			struct xfrm_state *x = sp->xvec[i];
 
 
3551			if (!xfrm_selector_match(&x->sel, &fl, family)) {
3552				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3553				return 0;
 
 
 
 
 
 
3554			}
3555		}
3556	}
3557
3558	pol = NULL;
3559	sk = sk_to_full_sk(sk);
3560	if (sk && sk->sk_policy[dir]) {
3561		pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3562		if (IS_ERR(pol)) {
3563			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3564			return 0;
3565		}
3566	}
3567
3568	if (!pol)
3569		pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3570
3571	if (IS_ERR(pol)) {
3572		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3573		return 0;
3574	}
3575
 
 
 
3576	if (!pol) {
 
 
 
 
 
3577		if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3578			xfrm_secpath_reject(xerr_idx, skb, &fl);
3579			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3580			return 0;
3581		}
3582		return 1;
3583	}
3584
3585	pol->curlft.use_time = ktime_get_real_seconds();
 
3586
3587	pols[0] = pol;
3588	npols++;
3589#ifdef CONFIG_XFRM_SUB_POLICY
3590	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3591		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3592						    &fl, family,
3593						    XFRM_POLICY_IN, if_id);
3594		if (pols[1]) {
3595			if (IS_ERR(pols[1])) {
3596				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
 
3597				return 0;
3598			}
3599			pols[1]->curlft.use_time = ktime_get_real_seconds();
 
 
3600			npols++;
3601		}
3602	}
3603#endif
3604
3605	if (pol->action == XFRM_POLICY_ALLOW) {
3606		static struct sec_path dummy;
3607		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3608		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3609		struct xfrm_tmpl **tpp = tp;
3610		int ti = 0;
3611		int i, k;
3612
3613		sp = skb_sec_path(skb);
3614		if (!sp)
3615			sp = &dummy;
3616
3617		for (pi = 0; pi < npols; pi++) {
3618			if (pols[pi] != pol &&
3619			    pols[pi]->action != XFRM_POLICY_ALLOW) {
3620				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3621				goto reject;
3622			}
3623			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3624				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3625				goto reject_error;
3626			}
3627			for (i = 0; i < pols[pi]->xfrm_nr; i++)
3628				tpp[ti++] = &pols[pi]->xfrm_vec[i];
3629		}
3630		xfrm_nr = ti;
 
3631		if (npols > 1) {
3632			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3633			tpp = stp;
3634		}
3635
3636		/* For each tunnel xfrm, find the first matching tmpl.
3637		 * For each tmpl before that, find corresponding xfrm.
3638		 * Order is _important_. Later we will implement
3639		 * some barriers, but at the moment barriers
3640		 * are implied between each two transformations.
 
 
 
3641		 */
3642		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3643			k = xfrm_policy_ok(tpp[i], sp, k, family);
3644			if (k < 0) {
3645				if (k < -1)
3646					/* "-2 - errored_index" returned */
3647					xerr_idx = -(2+k);
3648				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3649				goto reject;
3650			}
3651		}
3652
3653		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3654			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3655			goto reject;
3656		}
3657
3658		xfrm_pols_put(pols, npols);
 
 
3659		return 1;
3660	}
3661	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3662
3663reject:
3664	xfrm_secpath_reject(xerr_idx, skb, &fl);
3665reject_error:
3666	xfrm_pols_put(pols, npols);
3667	return 0;
3668}
3669EXPORT_SYMBOL(__xfrm_policy_check);
3670
3671int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3672{
3673	struct net *net = dev_net(skb->dev);
3674	struct flowi fl;
3675	struct dst_entry *dst;
3676	int res = 1;
3677
3678	if (xfrm_decode_session(skb, &fl, family) < 0) {
3679		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3680		return 0;
3681	}
3682
3683	skb_dst_force(skb);
3684	if (!skb_dst(skb)) {
3685		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3686		return 0;
3687	}
3688
3689	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3690	if (IS_ERR(dst)) {
3691		res = 0;
3692		dst = NULL;
3693	}
 
 
 
 
3694	skb_dst_set(skb, dst);
3695	return res;
3696}
3697EXPORT_SYMBOL(__xfrm_route_forward);
3698
3699/* Optimize later using cookies and generation ids. */
3700
3701static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3702{
3703	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3704	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3705	 * get validated by dst_ops->check on every use.  We do this
3706	 * because when a normal route referenced by an XFRM dst is
3707	 * obsoleted we do not go looking around for all parent
3708	 * referencing XFRM dsts so that we can invalidate them.  It
3709	 * is just too much work.  Instead we make the checks here on
3710	 * every use.  For example:
3711	 *
3712	 *	XFRM dst A --> IPv4 dst X
3713	 *
3714	 * X is the "xdst->route" of A (X is also the "dst->path" of A
3715	 * in this example).  If X is marked obsolete, "A" will not
3716	 * notice.  That's what we are validating here via the
3717	 * stale_bundle() check.
3718	 *
3719	 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3720	 * be marked on it.
3721	 * This will force stale_bundle() to fail on any xdst bundle with
3722	 * this dst linked in it.
3723	 */
3724	if (dst->obsolete < 0 && !stale_bundle(dst))
3725		return dst;
3726
3727	return NULL;
3728}
3729
3730static int stale_bundle(struct dst_entry *dst)
3731{
3732	return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3733}
3734
3735void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3736{
3737	while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3738		dst->dev = dev_net(dev)->loopback_dev;
3739		dev_hold(dst->dev);
3740		dev_put(dev);
3741	}
3742}
3743EXPORT_SYMBOL(xfrm_dst_ifdown);
3744
3745static void xfrm_link_failure(struct sk_buff *skb)
3746{
3747	/* Impossible. Such dst must be popped before reaches point of failure. */
3748}
3749
3750static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
3751{
3752	if (dst) {
3753		if (dst->obsolete) {
3754			dst_release(dst);
3755			dst = NULL;
3756		}
3757	}
3758	return dst;
3759}
3760
3761static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3762{
3763	while (nr--) {
3764		struct xfrm_dst *xdst = bundle[nr];
3765		u32 pmtu, route_mtu_cached;
3766		struct dst_entry *dst;
3767
3768		dst = &xdst->u.dst;
3769		pmtu = dst_mtu(xfrm_dst_child(dst));
3770		xdst->child_mtu_cached = pmtu;
3771
3772		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3773
3774		route_mtu_cached = dst_mtu(xdst->route);
3775		xdst->route_mtu_cached = route_mtu_cached;
3776
3777		if (pmtu > route_mtu_cached)
3778			pmtu = route_mtu_cached;
3779
3780		dst_metric_set(dst, RTAX_MTU, pmtu);
3781	}
3782}
3783
3784/* Check that the bundle accepts the flow and its components are
3785 * still valid.
3786 */
3787
3788static int xfrm_bundle_ok(struct xfrm_dst *first)
3789{
3790	struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3791	struct dst_entry *dst = &first->u.dst;
3792	struct xfrm_dst *xdst;
3793	int start_from, nr;
3794	u32 mtu;
3795
3796	if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3797	    (dst->dev && !netif_running(dst->dev)))
3798		return 0;
3799
3800	if (dst->flags & DST_XFRM_QUEUE)
3801		return 1;
3802
3803	start_from = nr = 0;
3804	do {
3805		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3806
3807		if (dst->xfrm->km.state != XFRM_STATE_VALID)
3808			return 0;
3809		if (xdst->xfrm_genid != dst->xfrm->genid)
3810			return 0;
3811		if (xdst->num_pols > 0 &&
3812		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3813			return 0;
3814
3815		bundle[nr++] = xdst;
3816
3817		mtu = dst_mtu(xfrm_dst_child(dst));
3818		if (xdst->child_mtu_cached != mtu) {
3819			start_from = nr;
3820			xdst->child_mtu_cached = mtu;
3821		}
3822
3823		if (!dst_check(xdst->route, xdst->route_cookie))
3824			return 0;
3825		mtu = dst_mtu(xdst->route);
3826		if (xdst->route_mtu_cached != mtu) {
3827			start_from = nr;
3828			xdst->route_mtu_cached = mtu;
3829		}
3830
3831		dst = xfrm_dst_child(dst);
3832	} while (dst->xfrm);
3833
3834	if (likely(!start_from))
3835		return 1;
3836
3837	xdst = bundle[start_from - 1];
3838	mtu = xdst->child_mtu_cached;
3839	while (start_from--) {
3840		dst = &xdst->u.dst;
3841
3842		mtu = xfrm_state_mtu(dst->xfrm, mtu);
3843		if (mtu > xdst->route_mtu_cached)
3844			mtu = xdst->route_mtu_cached;
3845		dst_metric_set(dst, RTAX_MTU, mtu);
3846		if (!start_from)
3847			break;
3848
3849		xdst = bundle[start_from - 1];
3850		xdst->child_mtu_cached = mtu;
3851	}
3852
3853	return 1;
3854}
3855
3856static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
3857{
3858	return dst_metric_advmss(xfrm_dst_path(dst));
3859}
3860
3861static unsigned int xfrm_mtu(const struct dst_entry *dst)
3862{
3863	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
3864
3865	return mtu ? : dst_mtu(xfrm_dst_path(dst));
3866}
3867
3868static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
3869					const void *daddr)
3870{
3871	while (dst->xfrm) {
3872		const struct xfrm_state *xfrm = dst->xfrm;
3873
3874		dst = xfrm_dst_child(dst);
3875
3876		if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
3877			continue;
3878		if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
3879			daddr = xfrm->coaddr;
3880		else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
3881			daddr = &xfrm->id.daddr;
3882	}
3883	return daddr;
3884}
3885
3886static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
3887					   struct sk_buff *skb,
3888					   const void *daddr)
3889{
3890	const struct dst_entry *path = xfrm_dst_path(dst);
3891
3892	if (!skb)
3893		daddr = xfrm_get_dst_nexthop(dst, daddr);
3894	return path->ops->neigh_lookup(path, skb, daddr);
3895}
3896
3897static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
3898{
3899	const struct dst_entry *path = xfrm_dst_path(dst);
3900
3901	daddr = xfrm_get_dst_nexthop(dst, daddr);
3902	path->ops->confirm_neigh(path, daddr);
3903}
3904
3905int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
3906{
3907	int err = 0;
3908
3909	if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
3910		return -EAFNOSUPPORT;
3911
3912	spin_lock(&xfrm_policy_afinfo_lock);
3913	if (unlikely(xfrm_policy_afinfo[family] != NULL))
3914		err = -EEXIST;
3915	else {
3916		struct dst_ops *dst_ops = afinfo->dst_ops;
3917		if (likely(dst_ops->kmem_cachep == NULL))
3918			dst_ops->kmem_cachep = xfrm_dst_cache;
3919		if (likely(dst_ops->check == NULL))
3920			dst_ops->check = xfrm_dst_check;
3921		if (likely(dst_ops->default_advmss == NULL))
3922			dst_ops->default_advmss = xfrm_default_advmss;
3923		if (likely(dst_ops->mtu == NULL))
3924			dst_ops->mtu = xfrm_mtu;
3925		if (likely(dst_ops->negative_advice == NULL))
3926			dst_ops->negative_advice = xfrm_negative_advice;
3927		if (likely(dst_ops->link_failure == NULL))
3928			dst_ops->link_failure = xfrm_link_failure;
3929		if (likely(dst_ops->neigh_lookup == NULL))
3930			dst_ops->neigh_lookup = xfrm_neigh_lookup;
3931		if (likely(!dst_ops->confirm_neigh))
3932			dst_ops->confirm_neigh = xfrm_confirm_neigh;
3933		rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
3934	}
3935	spin_unlock(&xfrm_policy_afinfo_lock);
3936
3937	return err;
3938}
3939EXPORT_SYMBOL(xfrm_policy_register_afinfo);
3940
3941void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
3942{
3943	struct dst_ops *dst_ops = afinfo->dst_ops;
3944	int i;
3945
3946	for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
3947		if (xfrm_policy_afinfo[i] != afinfo)
3948			continue;
3949		RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
3950		break;
3951	}
3952
3953	synchronize_rcu();
3954
3955	dst_ops->kmem_cachep = NULL;
3956	dst_ops->check = NULL;
3957	dst_ops->negative_advice = NULL;
3958	dst_ops->link_failure = NULL;
3959}
3960EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
3961
3962void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
3963{
3964	spin_lock(&xfrm_if_cb_lock);
3965	rcu_assign_pointer(xfrm_if_cb, ifcb);
3966	spin_unlock(&xfrm_if_cb_lock);
3967}
3968EXPORT_SYMBOL(xfrm_if_register_cb);
3969
3970void xfrm_if_unregister_cb(void)
3971{
3972	RCU_INIT_POINTER(xfrm_if_cb, NULL);
3973	synchronize_rcu();
3974}
3975EXPORT_SYMBOL(xfrm_if_unregister_cb);
3976
3977#ifdef CONFIG_XFRM_STATISTICS
3978static int __net_init xfrm_statistics_init(struct net *net)
3979{
3980	int rv;
3981	net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
3982	if (!net->mib.xfrm_statistics)
3983		return -ENOMEM;
3984	rv = xfrm_proc_init(net);
3985	if (rv < 0)
3986		free_percpu(net->mib.xfrm_statistics);
3987	return rv;
3988}
3989
3990static void xfrm_statistics_fini(struct net *net)
3991{
3992	xfrm_proc_fini(net);
3993	free_percpu(net->mib.xfrm_statistics);
3994}
3995#else
3996static int __net_init xfrm_statistics_init(struct net *net)
3997{
3998	return 0;
3999}
4000
4001static void xfrm_statistics_fini(struct net *net)
4002{
4003}
4004#endif
4005
4006static int __net_init xfrm_policy_init(struct net *net)
4007{
4008	unsigned int hmask, sz;
4009	int dir, err;
4010
4011	if (net_eq(net, &init_net)) {
4012		xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
4013					   sizeof(struct xfrm_dst),
4014					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
4015					   NULL);
4016		err = rhashtable_init(&xfrm_policy_inexact_table,
4017				      &xfrm_pol_inexact_params);
4018		BUG_ON(err);
4019	}
4020
4021	hmask = 8 - 1;
4022	sz = (hmask+1) * sizeof(struct hlist_head);
4023
4024	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4025	if (!net->xfrm.policy_byidx)
4026		goto out_byidx;
4027	net->xfrm.policy_idx_hmask = hmask;
4028
4029	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4030		struct xfrm_policy_hash *htab;
4031
4032		net->xfrm.policy_count[dir] = 0;
4033		net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4034		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4035
4036		htab = &net->xfrm.policy_bydst[dir];
4037		htab->table = xfrm_hash_alloc(sz);
4038		if (!htab->table)
4039			goto out_bydst;
4040		htab->hmask = hmask;
4041		htab->dbits4 = 32;
4042		htab->sbits4 = 32;
4043		htab->dbits6 = 128;
4044		htab->sbits6 = 128;
4045	}
4046	net->xfrm.policy_hthresh.lbits4 = 32;
4047	net->xfrm.policy_hthresh.rbits4 = 32;
4048	net->xfrm.policy_hthresh.lbits6 = 128;
4049	net->xfrm.policy_hthresh.rbits6 = 128;
4050
4051	seqlock_init(&net->xfrm.policy_hthresh.lock);
4052
4053	INIT_LIST_HEAD(&net->xfrm.policy_all);
4054	INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4055	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4056	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4057	return 0;
4058
4059out_bydst:
4060	for (dir--; dir >= 0; dir--) {
4061		struct xfrm_policy_hash *htab;
4062
4063		htab = &net->xfrm.policy_bydst[dir];
4064		xfrm_hash_free(htab->table, sz);
4065	}
4066	xfrm_hash_free(net->xfrm.policy_byidx, sz);
4067out_byidx:
4068	return -ENOMEM;
4069}
4070
4071static void xfrm_policy_fini(struct net *net)
4072{
4073	struct xfrm_pol_inexact_bin *b, *t;
4074	unsigned int sz;
4075	int dir;
4076
4077	flush_work(&net->xfrm.policy_hash_work);
4078#ifdef CONFIG_XFRM_SUB_POLICY
4079	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4080#endif
4081	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4082
4083	WARN_ON(!list_empty(&net->xfrm.policy_all));
4084
4085	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4086		struct xfrm_policy_hash *htab;
4087
4088		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4089
4090		htab = &net->xfrm.policy_bydst[dir];
4091		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4092		WARN_ON(!hlist_empty(htab->table));
4093		xfrm_hash_free(htab->table, sz);
4094	}
4095
4096	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4097	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4098	xfrm_hash_free(net->xfrm.policy_byidx, sz);
4099
4100	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4101	list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4102		__xfrm_policy_inexact_prune_bin(b, true);
4103	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4104}
4105
4106static int __net_init xfrm_net_init(struct net *net)
4107{
4108	int rv;
4109
4110	/* Initialize the per-net locks here */
4111	spin_lock_init(&net->xfrm.xfrm_state_lock);
4112	spin_lock_init(&net->xfrm.xfrm_policy_lock);
 
4113	mutex_init(&net->xfrm.xfrm_cfg_mutex);
 
 
 
4114
4115	rv = xfrm_statistics_init(net);
4116	if (rv < 0)
4117		goto out_statistics;
4118	rv = xfrm_state_init(net);
4119	if (rv < 0)
4120		goto out_state;
4121	rv = xfrm_policy_init(net);
4122	if (rv < 0)
4123		goto out_policy;
4124	rv = xfrm_sysctl_init(net);
4125	if (rv < 0)
4126		goto out_sysctl;
4127
4128	return 0;
4129
4130out_sysctl:
4131	xfrm_policy_fini(net);
4132out_policy:
4133	xfrm_state_fini(net);
4134out_state:
4135	xfrm_statistics_fini(net);
4136out_statistics:
4137	return rv;
4138}
4139
4140static void __net_exit xfrm_net_exit(struct net *net)
4141{
4142	xfrm_sysctl_fini(net);
4143	xfrm_policy_fini(net);
4144	xfrm_state_fini(net);
4145	xfrm_statistics_fini(net);
4146}
4147
4148static struct pernet_operations __net_initdata xfrm_net_ops = {
4149	.init = xfrm_net_init,
4150	.exit = xfrm_net_exit,
4151};
4152
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4153void __init xfrm_init(void)
4154{
 
 
 
 
4155	register_pernet_subsys(&xfrm_net_ops);
4156	xfrm_dev_init();
4157	seqcount_init(&xfrm_policy_hash_generation);
4158	xfrm_input_init();
4159
4160	RCU_INIT_POINTER(xfrm_if_cb, NULL);
4161	synchronize_rcu();
 
 
 
4162}
4163
4164#ifdef CONFIG_AUDITSYSCALL
4165static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4166					 struct audit_buffer *audit_buf)
4167{
4168	struct xfrm_sec_ctx *ctx = xp->security;
4169	struct xfrm_selector *sel = &xp->selector;
4170
4171	if (ctx)
4172		audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4173				 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4174
4175	switch (sel->family) {
4176	case AF_INET:
4177		audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4178		if (sel->prefixlen_s != 32)
4179			audit_log_format(audit_buf, " src_prefixlen=%d",
4180					 sel->prefixlen_s);
4181		audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4182		if (sel->prefixlen_d != 32)
4183			audit_log_format(audit_buf, " dst_prefixlen=%d",
4184					 sel->prefixlen_d);
4185		break;
4186	case AF_INET6:
4187		audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4188		if (sel->prefixlen_s != 128)
4189			audit_log_format(audit_buf, " src_prefixlen=%d",
4190					 sel->prefixlen_s);
4191		audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4192		if (sel->prefixlen_d != 128)
4193			audit_log_format(audit_buf, " dst_prefixlen=%d",
4194					 sel->prefixlen_d);
4195		break;
4196	}
4197}
4198
4199void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4200{
4201	struct audit_buffer *audit_buf;
4202
4203	audit_buf = xfrm_audit_start("SPD-add");
4204	if (audit_buf == NULL)
4205		return;
4206	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4207	audit_log_format(audit_buf, " res=%u", result);
4208	xfrm_audit_common_policyinfo(xp, audit_buf);
4209	audit_log_end(audit_buf);
4210}
4211EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4212
4213void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4214			      bool task_valid)
4215{
4216	struct audit_buffer *audit_buf;
4217
4218	audit_buf = xfrm_audit_start("SPD-delete");
4219	if (audit_buf == NULL)
4220		return;
4221	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4222	audit_log_format(audit_buf, " res=%u", result);
4223	xfrm_audit_common_policyinfo(xp, audit_buf);
4224	audit_log_end(audit_buf);
4225}
4226EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4227#endif
4228
4229#ifdef CONFIG_XFRM_MIGRATE
4230static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4231					const struct xfrm_selector *sel_tgt)
4232{
4233	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4234		if (sel_tgt->family == sel_cmp->family &&
4235		    xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4236				    sel_cmp->family) &&
4237		    xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4238				    sel_cmp->family) &&
4239		    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4240		    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4241			return true;
4242		}
4243	} else {
4244		if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4245			return true;
4246		}
4247	}
4248	return false;
4249}
4250
4251static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4252						    u8 dir, u8 type, struct net *net)
4253{
4254	struct xfrm_policy *pol, *ret = NULL;
4255	struct hlist_head *chain;
4256	u32 priority = ~0U;
4257
4258	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4259	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4260	hlist_for_each_entry(pol, chain, bydst) {
4261		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
 
4262		    pol->type == type) {
4263			ret = pol;
4264			priority = ret->priority;
4265			break;
4266		}
4267	}
4268	chain = &net->xfrm.policy_inexact[dir];
4269	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4270		if ((pol->priority >= priority) && ret)
4271			break;
4272
4273		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
 
4274		    pol->type == type) {
4275			ret = pol;
4276			break;
4277		}
4278	}
4279
4280	xfrm_pol_hold(ret);
4281
4282	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4283
4284	return ret;
4285}
4286
4287static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4288{
4289	int match = 0;
4290
4291	if (t->mode == m->mode && t->id.proto == m->proto &&
4292	    (m->reqid == 0 || t->reqid == m->reqid)) {
4293		switch (t->mode) {
4294		case XFRM_MODE_TUNNEL:
4295		case XFRM_MODE_BEET:
4296			if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4297					    m->old_family) &&
4298			    xfrm_addr_equal(&t->saddr, &m->old_saddr,
4299					    m->old_family)) {
4300				match = 1;
4301			}
4302			break;
4303		case XFRM_MODE_TRANSPORT:
4304			/* in case of transport mode, template does not store
4305			   any IP addresses, hence we just compare mode and
4306			   protocol */
4307			match = 1;
4308			break;
4309		default:
4310			break;
4311		}
4312	}
4313	return match;
4314}
4315
4316/* update endpoint address(es) of template(s) */
4317static int xfrm_policy_migrate(struct xfrm_policy *pol,
4318			       struct xfrm_migrate *m, int num_migrate)
 
4319{
4320	struct xfrm_migrate *mp;
4321	int i, j, n = 0;
4322
4323	write_lock_bh(&pol->lock);
4324	if (unlikely(pol->walk.dead)) {
4325		/* target policy has been deleted */
 
4326		write_unlock_bh(&pol->lock);
4327		return -ENOENT;
4328	}
4329
4330	for (i = 0; i < pol->xfrm_nr; i++) {
4331		for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4332			if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4333				continue;
4334			n++;
4335			if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4336			    pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4337				continue;
4338			/* update endpoints */
4339			memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4340			       sizeof(pol->xfrm_vec[i].id.daddr));
4341			memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4342			       sizeof(pol->xfrm_vec[i].saddr));
4343			pol->xfrm_vec[i].encap_family = mp->new_family;
4344			/* flush bundles */
4345			atomic_inc(&pol->genid);
4346		}
4347	}
4348
4349	write_unlock_bh(&pol->lock);
4350
4351	if (!n)
4352		return -ENODATA;
4353
4354	return 0;
4355}
4356
4357static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
 
4358{
4359	int i, j;
4360
4361	if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
 
4362		return -EINVAL;
 
4363
4364	for (i = 0; i < num_migrate; i++) {
4365		if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4366		    xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
 
4367			return -EINVAL;
 
4368
4369		/* check if there is any duplicated entry */
4370		for (j = i + 1; j < num_migrate; j++) {
4371			if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4372				    sizeof(m[i].old_daddr)) &&
4373			    !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4374				    sizeof(m[i].old_saddr)) &&
4375			    m[i].proto == m[j].proto &&
4376			    m[i].mode == m[j].mode &&
4377			    m[i].reqid == m[j].reqid &&
4378			    m[i].old_family == m[j].old_family)
 
4379				return -EINVAL;
 
4380		}
4381	}
4382
4383	return 0;
4384}
4385
4386int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4387		 struct xfrm_migrate *m, int num_migrate,
4388		 struct xfrm_kmaddress *k, struct net *net,
4389		 struct xfrm_encap_tmpl *encap)
 
4390{
4391	int i, err, nx_cur = 0, nx_new = 0;
4392	struct xfrm_policy *pol = NULL;
4393	struct xfrm_state *x, *xc;
4394	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4395	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4396	struct xfrm_migrate *mp;
4397
4398	/* Stage 0 - sanity checks */
4399	if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
 
4400		goto out;
4401
4402	if (dir >= XFRM_POLICY_MAX) {
 
4403		err = -EINVAL;
4404		goto out;
4405	}
4406
4407	/* Stage 1 - find policy */
4408	if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
 
 
4409		err = -ENOENT;
4410		goto out;
4411	}
4412
4413	/* Stage 2 - find and update state(s) */
4414	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4415		if ((x = xfrm_migrate_state_find(mp, net))) {
4416			x_cur[nx_cur] = x;
4417			nx_cur++;
4418			xc = xfrm_state_migrate(x, mp, encap);
4419			if (xc) {
4420				x_new[nx_new] = xc;
4421				nx_new++;
4422			} else {
4423				err = -ENODATA;
4424				goto restore_state;
4425			}
4426		}
4427	}
4428
4429	/* Stage 3 - update policy */
4430	if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
 
4431		goto restore_state;
4432
4433	/* Stage 4 - delete old state(s) */
4434	if (nx_cur) {
4435		xfrm_states_put(x_cur, nx_cur);
4436		xfrm_states_delete(x_cur, nx_cur);
4437	}
4438
4439	/* Stage 5 - announce */
4440	km_migrate(sel, dir, type, m, num_migrate, k, encap);
4441
4442	xfrm_pol_put(pol);
4443
4444	return 0;
4445out:
4446	return err;
4447
4448restore_state:
4449	if (pol)
4450		xfrm_pol_put(pol);
4451	if (nx_cur)
4452		xfrm_states_put(x_cur, nx_cur);
4453	if (nx_new)
4454		xfrm_states_delete(x_new, nx_new);
4455
4456	return err;
4457}
4458EXPORT_SYMBOL(xfrm_migrate);
4459#endif
v6.9.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * xfrm_policy.c
   4 *
   5 * Changes:
   6 *	Mitsuru KANDA @USAGI
   7 * 	Kazunori MIYAZAWA @USAGI
   8 * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   9 * 		IPv6 support
  10 * 	Kazunori MIYAZAWA @USAGI
  11 * 	YOSHIFUJI Hideaki
  12 * 		Split up af-specific portion
  13 *	Derek Atkins <derek@ihtfp.com>		Add the post_input processor
  14 *
  15 */
  16
  17#include <linux/err.h>
  18#include <linux/slab.h>
  19#include <linux/kmod.h>
  20#include <linux/list.h>
  21#include <linux/spinlock.h>
  22#include <linux/workqueue.h>
  23#include <linux/notifier.h>
  24#include <linux/netdevice.h>
  25#include <linux/netfilter.h>
  26#include <linux/module.h>
  27#include <linux/cache.h>
  28#include <linux/cpu.h>
  29#include <linux/audit.h>
  30#include <linux/rhashtable.h>
  31#include <linux/if_tunnel.h>
  32#include <linux/icmp.h>
  33#include <net/dst.h>
  34#include <net/flow.h>
  35#include <net/inet_ecn.h>
  36#include <net/xfrm.h>
  37#include <net/ip.h>
  38#include <net/gre.h>
  39#if IS_ENABLED(CONFIG_IPV6_MIP6)
  40#include <net/mip6.h>
  41#endif
  42#ifdef CONFIG_XFRM_STATISTICS
  43#include <net/snmp.h>
  44#endif
  45#ifdef CONFIG_XFRM_ESPINTCP
  46#include <net/espintcp.h>
  47#endif
  48
  49#include "xfrm_hash.h"
  50
  51#define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
  52#define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
  53#define XFRM_MAX_QUEUE_LEN	100
  54
  55struct xfrm_flo {
  56	struct dst_entry *dst_orig;
  57	u8 flags;
  58};
  59
  60/* prefixes smaller than this are stored in lists, not trees. */
  61#define INEXACT_PREFIXLEN_IPV4	16
  62#define INEXACT_PREFIXLEN_IPV6	48
  63
  64struct xfrm_pol_inexact_node {
  65	struct rb_node node;
  66	union {
  67		xfrm_address_t addr;
  68		struct rcu_head rcu;
  69	};
  70	u8 prefixlen;
  71
  72	struct rb_root root;
  73
  74	/* the policies matching this node, can be empty list */
  75	struct hlist_head hhead;
  76};
  77
  78/* xfrm inexact policy search tree:
  79 * xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
  80 *  |
  81 * +---- root_d: sorted by daddr:prefix
  82 * |                 |
  83 * |        xfrm_pol_inexact_node
  84 * |                 |
  85 * |                 +- root: sorted by saddr/prefix
  86 * |                 |              |
  87 * |                 |         xfrm_pol_inexact_node
  88 * |                 |              |
  89 * |                 |              + root: unused
  90 * |                 |              |
  91 * |                 |              + hhead: saddr:daddr policies
  92 * |                 |
  93 * |                 +- coarse policies and all any:daddr policies
  94 * |
  95 * +---- root_s: sorted by saddr:prefix
  96 * |                 |
  97 * |        xfrm_pol_inexact_node
  98 * |                 |
  99 * |                 + root: unused
 100 * |                 |
 101 * |                 + hhead: saddr:any policies
 102 * |
 103 * +---- coarse policies and all any:any policies
 104 *
 105 * Lookups return four candidate lists:
 106 * 1. any:any list from top-level xfrm_pol_inexact_bin
 107 * 2. any:daddr list from daddr tree
 108 * 3. saddr:daddr list from 2nd level daddr tree
 109 * 4. saddr:any list from saddr tree
 110 *
 111 * This result set then needs to be searched for the policy with
 112 * the lowest priority.  If two results have same prio, youngest one wins.
 113 */
 114
 115struct xfrm_pol_inexact_key {
 116	possible_net_t net;
 117	u32 if_id;
 118	u16 family;
 119	u8 dir, type;
 120};
 121
 122struct xfrm_pol_inexact_bin {
 123	struct xfrm_pol_inexact_key k;
 124	struct rhash_head head;
 125	/* list containing '*:*' policies */
 126	struct hlist_head hhead;
 127
 128	seqcount_spinlock_t count;
 129	/* tree sorted by daddr/prefix */
 130	struct rb_root root_d;
 131
 132	/* tree sorted by saddr/prefix */
 133	struct rb_root root_s;
 134
 135	/* slow path below */
 136	struct list_head inexact_bins;
 137	struct rcu_head rcu;
 138};
 139
 140enum xfrm_pol_inexact_candidate_type {
 141	XFRM_POL_CAND_BOTH,
 142	XFRM_POL_CAND_SADDR,
 143	XFRM_POL_CAND_DADDR,
 144	XFRM_POL_CAND_ANY,
 145
 146	XFRM_POL_CAND_MAX,
 147};
 148
 149struct xfrm_pol_inexact_candidates {
 150	struct hlist_head *res[XFRM_POL_CAND_MAX];
 151};
 152
 153struct xfrm_flow_keys {
 154	struct flow_dissector_key_basic basic;
 155	struct flow_dissector_key_control control;
 156	union {
 157		struct flow_dissector_key_ipv4_addrs ipv4;
 158		struct flow_dissector_key_ipv6_addrs ipv6;
 159	} addrs;
 160	struct flow_dissector_key_ip ip;
 161	struct flow_dissector_key_icmp icmp;
 162	struct flow_dissector_key_ports ports;
 163	struct flow_dissector_key_keyid gre;
 164};
 165
 166static struct flow_dissector xfrm_session_dissector __ro_after_init;
 167
 168static DEFINE_SPINLOCK(xfrm_if_cb_lock);
 169static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
 170
 171static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
 172static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 173						__read_mostly;
 174
 175static struct kmem_cache *xfrm_dst_cache __ro_after_init;
 
 176
 177static struct rhashtable xfrm_policy_inexact_table;
 178static const struct rhashtable_params xfrm_pol_inexact_params;
 179
 180static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
 181static int stale_bundle(struct dst_entry *dst);
 182static int xfrm_bundle_ok(struct xfrm_dst *xdst);
 183static void xfrm_policy_queue_process(struct timer_list *t);
 184
 185static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
 186static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 187						int dir);
 188
 189static struct xfrm_pol_inexact_bin *
 190xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
 191			   u32 if_id);
 192
 193static struct xfrm_pol_inexact_bin *
 194xfrm_policy_inexact_lookup_rcu(struct net *net,
 195			       u8 type, u16 family, u8 dir, u32 if_id);
 196static struct xfrm_policy *
 197xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
 198			bool excl);
 199static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
 200					    struct xfrm_policy *policy);
 201
 202static bool
 203xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
 204				    struct xfrm_pol_inexact_bin *b,
 205				    const xfrm_address_t *saddr,
 206				    const xfrm_address_t *daddr);
 207
 208static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
 209{
 210	return refcount_inc_not_zero(&policy->refcnt);
 211}
 212
 213static inline bool
 214__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 215{
 216	const struct flowi4 *fl4 = &fl->u.ip4;
 217
 218	return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
 219		addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
 220		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
 221		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
 222		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
 223		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 224}
 225
 226static inline bool
 227__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 228{
 229	const struct flowi6 *fl6 = &fl->u.ip6;
 230
 231	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
 232		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
 233		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
 234		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
 235		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
 236		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 237}
 238
 239bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
 240			 unsigned short family)
 241{
 242	switch (family) {
 243	case AF_INET:
 244		return __xfrm4_selector_match(sel, fl);
 245	case AF_INET6:
 246		return __xfrm6_selector_match(sel, fl);
 247	}
 248	return false;
 249}
 250
 251static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 252{
 253	const struct xfrm_policy_afinfo *afinfo;
 254
 255	if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 256		return NULL;
 257	rcu_read_lock();
 258	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
 259	if (unlikely(!afinfo))
 260		rcu_read_unlock();
 261	return afinfo;
 262}
 263
 264/* Called with rcu_read_lock(). */
 265static const struct xfrm_if_cb *xfrm_if_get_cb(void)
 266{
 267	return rcu_dereference(xfrm_if_cb);
 268}
 269
 270struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
 271				    const xfrm_address_t *saddr,
 272				    const xfrm_address_t *daddr,
 273				    int family, u32 mark)
 274{
 275	const struct xfrm_policy_afinfo *afinfo;
 276	struct dst_entry *dst;
 277
 278	afinfo = xfrm_policy_get_afinfo(family);
 279	if (unlikely(afinfo == NULL))
 280		return ERR_PTR(-EAFNOSUPPORT);
 281
 282	dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
 283
 284	rcu_read_unlock();
 285
 286	return dst;
 287}
 288EXPORT_SYMBOL(__xfrm_dst_lookup);
 289
 290static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
 291						int tos, int oif,
 292						xfrm_address_t *prev_saddr,
 293						xfrm_address_t *prev_daddr,
 294						int family, u32 mark)
 295{
 296	struct net *net = xs_net(x);
 297	xfrm_address_t *saddr = &x->props.saddr;
 298	xfrm_address_t *daddr = &x->id.daddr;
 299	struct dst_entry *dst;
 300
 301	if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
 302		saddr = x->coaddr;
 303		daddr = prev_daddr;
 304	}
 305	if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
 306		saddr = prev_saddr;
 307		daddr = x->coaddr;
 308	}
 309
 310	dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
 311
 312	if (!IS_ERR(dst)) {
 313		if (prev_saddr != saddr)
 314			memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
 315		if (prev_daddr != daddr)
 316			memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
 317	}
 318
 319	return dst;
 320}
 321
 322static inline unsigned long make_jiffies(long secs)
 323{
 324	if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
 325		return MAX_SCHEDULE_TIMEOUT-1;
 326	else
 327		return secs*HZ;
 328}
 329
 330static void xfrm_policy_timer(struct timer_list *t)
 331{
 332	struct xfrm_policy *xp = from_timer(xp, t, timer);
 333	time64_t now = ktime_get_real_seconds();
 334	time64_t next = TIME64_MAX;
 335	int warn = 0;
 336	int dir;
 337
 338	read_lock(&xp->lock);
 339
 340	if (unlikely(xp->walk.dead))
 341		goto out;
 342
 343	dir = xfrm_policy_id2dir(xp->index);
 344
 345	if (xp->lft.hard_add_expires_seconds) {
 346		time64_t tmo = xp->lft.hard_add_expires_seconds +
 347			xp->curlft.add_time - now;
 348		if (tmo <= 0)
 349			goto expired;
 350		if (tmo < next)
 351			next = tmo;
 352	}
 353	if (xp->lft.hard_use_expires_seconds) {
 354		time64_t tmo = xp->lft.hard_use_expires_seconds +
 355			(READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 356		if (tmo <= 0)
 357			goto expired;
 358		if (tmo < next)
 359			next = tmo;
 360	}
 361	if (xp->lft.soft_add_expires_seconds) {
 362		time64_t tmo = xp->lft.soft_add_expires_seconds +
 363			xp->curlft.add_time - now;
 364		if (tmo <= 0) {
 365			warn = 1;
 366			tmo = XFRM_KM_TIMEOUT;
 367		}
 368		if (tmo < next)
 369			next = tmo;
 370	}
 371	if (xp->lft.soft_use_expires_seconds) {
 372		time64_t tmo = xp->lft.soft_use_expires_seconds +
 373			(READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
 374		if (tmo <= 0) {
 375			warn = 1;
 376			tmo = XFRM_KM_TIMEOUT;
 377		}
 378		if (tmo < next)
 379			next = tmo;
 380	}
 381
 382	if (warn)
 383		km_policy_expired(xp, dir, 0, 0);
 384	if (next != TIME64_MAX &&
 385	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
 386		xfrm_pol_hold(xp);
 387
 388out:
 389	read_unlock(&xp->lock);
 390	xfrm_pol_put(xp);
 391	return;
 392
 393expired:
 394	read_unlock(&xp->lock);
 395	if (!xfrm_policy_delete(xp, dir))
 396		km_policy_expired(xp, dir, 1, 0);
 397	xfrm_pol_put(xp);
 398}
 399
 400/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
 401 * SPD calls.
 402 */
 403
 404struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 405{
 406	struct xfrm_policy *policy;
 407
 408	policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 409
 410	if (policy) {
 411		write_pnet(&policy->xp_net, net);
 412		INIT_LIST_HEAD(&policy->walk.all);
 413		INIT_HLIST_NODE(&policy->bydst_inexact_list);
 414		INIT_HLIST_NODE(&policy->bydst);
 415		INIT_HLIST_NODE(&policy->byidx);
 416		rwlock_init(&policy->lock);
 417		refcount_set(&policy->refcnt, 1);
 418		skb_queue_head_init(&policy->polq.hold_queue);
 419		timer_setup(&policy->timer, xfrm_policy_timer, 0);
 420		timer_setup(&policy->polq.hold_timer,
 421			    xfrm_policy_queue_process, 0);
 422	}
 423	return policy;
 424}
 425EXPORT_SYMBOL(xfrm_policy_alloc);
 426
 427static void xfrm_policy_destroy_rcu(struct rcu_head *head)
 428{
 429	struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
 430
 431	security_xfrm_policy_free(policy->security);
 432	kfree(policy);
 433}
 434
 435/* Destroy xfrm_policy: descendant resources must be released to this moment. */
 436
 437void xfrm_policy_destroy(struct xfrm_policy *policy)
 438{
 439	BUG_ON(!policy->walk.dead);
 440
 441	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 442		BUG();
 443
 444	xfrm_dev_policy_free(policy);
 445	call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 446}
 447EXPORT_SYMBOL(xfrm_policy_destroy);
 448
 449/* Rule must be locked. Release descendant resources, announce
 450 * entry dead. The rule must be unlinked from lists to the moment.
 451 */
 452
 453static void xfrm_policy_kill(struct xfrm_policy *policy)
 454{
 455	write_lock_bh(&policy->lock);
 456	policy->walk.dead = 1;
 457	write_unlock_bh(&policy->lock);
 458
 459	atomic_inc(&policy->genid);
 460
 461	if (del_timer(&policy->polq.hold_timer))
 462		xfrm_pol_put(policy);
 463	skb_queue_purge(&policy->polq.hold_queue);
 464
 465	if (del_timer(&policy->timer))
 466		xfrm_pol_put(policy);
 467
 468	xfrm_pol_put(policy);
 469}
 470
 471static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
 472
 473static inline unsigned int idx_hash(struct net *net, u32 index)
 474{
 475	return __idx_hash(index, net->xfrm.policy_idx_hmask);
 476}
 477
 478/* calculate policy hash thresholds */
 479static void __get_hash_thresh(struct net *net,
 480			      unsigned short family, int dir,
 481			      u8 *dbits, u8 *sbits)
 482{
 483	switch (family) {
 484	case AF_INET:
 485		*dbits = net->xfrm.policy_bydst[dir].dbits4;
 486		*sbits = net->xfrm.policy_bydst[dir].sbits4;
 487		break;
 488
 489	case AF_INET6:
 490		*dbits = net->xfrm.policy_bydst[dir].dbits6;
 491		*sbits = net->xfrm.policy_bydst[dir].sbits6;
 492		break;
 493
 494	default:
 495		*dbits = 0;
 496		*sbits = 0;
 497	}
 498}
 499
 500static struct hlist_head *policy_hash_bysel(struct net *net,
 501					    const struct xfrm_selector *sel,
 502					    unsigned short family, int dir)
 503{
 504	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 505	unsigned int hash;
 506	u8 dbits;
 507	u8 sbits;
 508
 509	__get_hash_thresh(net, family, dir, &dbits, &sbits);
 510	hash = __sel_hash(sel, family, hmask, dbits, sbits);
 511
 512	if (hash == hmask + 1)
 513		return NULL;
 514
 515	return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 516		     lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 517}
 518
 519static struct hlist_head *policy_hash_direct(struct net *net,
 520					     const xfrm_address_t *daddr,
 521					     const xfrm_address_t *saddr,
 522					     unsigned short family, int dir)
 523{
 524	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 525	unsigned int hash;
 526	u8 dbits;
 527	u8 sbits;
 528
 529	__get_hash_thresh(net, family, dir, &dbits, &sbits);
 530	hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
 531
 532	return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
 533		     lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
 534}
 535
 536static void xfrm_dst_hash_transfer(struct net *net,
 537				   struct hlist_head *list,
 538				   struct hlist_head *ndsttable,
 539				   unsigned int nhashmask,
 540				   int dir)
 541{
 542	struct hlist_node *tmp, *entry0 = NULL;
 543	struct xfrm_policy *pol;
 544	unsigned int h0 = 0;
 545	u8 dbits;
 546	u8 sbits;
 547
 548redo:
 549	hlist_for_each_entry_safe(pol, tmp, list, bydst) {
 550		unsigned int h;
 551
 552		__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
 553		h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
 554				pol->family, nhashmask, dbits, sbits);
 555		if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) {
 556			hlist_del_rcu(&pol->bydst);
 557			hlist_add_head_rcu(&pol->bydst, ndsttable + h);
 558			h0 = h;
 559		} else {
 560			if (h != h0)
 561				continue;
 562			hlist_del_rcu(&pol->bydst);
 563			hlist_add_behind_rcu(&pol->bydst, entry0);
 564		}
 565		entry0 = &pol->bydst;
 566	}
 567	if (!hlist_empty(list)) {
 568		entry0 = NULL;
 569		goto redo;
 570	}
 571}
 572
 573static void xfrm_idx_hash_transfer(struct hlist_head *list,
 574				   struct hlist_head *nidxtable,
 575				   unsigned int nhashmask)
 576{
 577	struct hlist_node *tmp;
 578	struct xfrm_policy *pol;
 579
 580	hlist_for_each_entry_safe(pol, tmp, list, byidx) {
 581		unsigned int h;
 582
 583		h = __idx_hash(pol->index, nhashmask);
 584		hlist_add_head(&pol->byidx, nidxtable+h);
 585	}
 586}
 587
 588static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
 589{
 590	return ((old_hmask + 1) << 1) - 1;
 591}
 592
 593static void xfrm_bydst_resize(struct net *net, int dir)
 594{
 595	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 596	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 597	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 598	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
 599	struct hlist_head *odst;
 600	int i;
 601
 602	if (!ndst)
 603		return;
 604
 605	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 606	write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
 607
 608	odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
 609				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 610
 611	for (i = hmask; i >= 0; i--)
 612		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
 613
 614	rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
 615	net->xfrm.policy_bydst[dir].hmask = nhashmask;
 616
 617	write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
 618	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 619
 620	synchronize_rcu();
 621
 622	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
 623}
 624
 625static void xfrm_byidx_resize(struct net *net)
 626{
 627	unsigned int hmask = net->xfrm.policy_idx_hmask;
 628	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
 629	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
 630	struct hlist_head *oidx = net->xfrm.policy_byidx;
 631	struct hlist_head *nidx = xfrm_hash_alloc(nsize);
 632	int i;
 633
 634	if (!nidx)
 635		return;
 636
 637	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
 638
 639	for (i = hmask; i >= 0; i--)
 640		xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
 641
 642	net->xfrm.policy_byidx = nidx;
 643	net->xfrm.policy_idx_hmask = nhashmask;
 644
 645	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
 646
 647	xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
 648}
 649
 650static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
 651{
 652	unsigned int cnt = net->xfrm.policy_count[dir];
 653	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 654
 655	if (total)
 656		*total += cnt;
 657
 658	if ((hmask + 1) < xfrm_policy_hashmax &&
 659	    cnt > hmask)
 660		return 1;
 661
 662	return 0;
 663}
 664
 665static inline int xfrm_byidx_should_resize(struct net *net, int total)
 666{
 667	unsigned int hmask = net->xfrm.policy_idx_hmask;
 668
 669	if ((hmask + 1) < xfrm_policy_hashmax &&
 670	    total > hmask)
 671		return 1;
 672
 673	return 0;
 674}
 675
 676void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
 677{
 678	si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
 679	si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
 680	si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
 681	si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
 682	si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
 683	si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
 684	si->spdhcnt = net->xfrm.policy_idx_hmask;
 685	si->spdhmcnt = xfrm_policy_hashmax;
 686}
 687EXPORT_SYMBOL(xfrm_spd_getinfo);
 688
 689static DEFINE_MUTEX(hash_resize_mutex);
 690static void xfrm_hash_resize(struct work_struct *work)
 691{
 692	struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
 693	int dir, total;
 694
 695	mutex_lock(&hash_resize_mutex);
 696
 697	total = 0;
 698	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
 699		if (xfrm_bydst_should_resize(net, dir, &total))
 700			xfrm_bydst_resize(net, dir);
 701	}
 702	if (xfrm_byidx_should_resize(net, total))
 703		xfrm_byidx_resize(net);
 704
 705	mutex_unlock(&hash_resize_mutex);
 706}
 707
 708/* Make sure *pol can be inserted into fastbin.
 709 * Useful to check that later insert requests will be successful
 710 * (provided xfrm_policy_lock is held throughout).
 711 */
 712static struct xfrm_pol_inexact_bin *
 713xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
 714{
 715	struct xfrm_pol_inexact_bin *bin, *prev;
 716	struct xfrm_pol_inexact_key k = {
 717		.family = pol->family,
 718		.type = pol->type,
 719		.dir = dir,
 720		.if_id = pol->if_id,
 721	};
 722	struct net *net = xp_net(pol);
 723
 724	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
 725
 726	write_pnet(&k.net, net);
 727	bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
 728				     xfrm_pol_inexact_params);
 729	if (bin)
 730		return bin;
 731
 732	bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
 733	if (!bin)
 734		return NULL;
 735
 736	bin->k = k;
 737	INIT_HLIST_HEAD(&bin->hhead);
 738	bin->root_d = RB_ROOT;
 739	bin->root_s = RB_ROOT;
 740	seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
 741
 742	prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
 743						&bin->k, &bin->head,
 744						xfrm_pol_inexact_params);
 745	if (!prev) {
 746		list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
 747		return bin;
 748	}
 749
 750	kfree(bin);
 751
 752	return IS_ERR(prev) ? NULL : prev;
 753}
 754
 755static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
 756					       int family, u8 prefixlen)
 757{
 758	if (xfrm_addr_any(addr, family))
 759		return true;
 760
 761	if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
 762		return true;
 763
 764	if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
 765		return true;
 766
 767	return false;
 768}
 769
 770static bool
 771xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
 772{
 773	const xfrm_address_t *addr;
 774	bool saddr_any, daddr_any;
 775	u8 prefixlen;
 776
 777	addr = &policy->selector.saddr;
 778	prefixlen = policy->selector.prefixlen_s;
 779
 780	saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 781						       policy->family,
 782						       prefixlen);
 783	addr = &policy->selector.daddr;
 784	prefixlen = policy->selector.prefixlen_d;
 785	daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
 786						       policy->family,
 787						       prefixlen);
 788	return saddr_any && daddr_any;
 789}
 790
 791static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
 792				       const xfrm_address_t *addr, u8 prefixlen)
 793{
 794	node->addr = *addr;
 795	node->prefixlen = prefixlen;
 796}
 797
 798static struct xfrm_pol_inexact_node *
 799xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
 800{
 801	struct xfrm_pol_inexact_node *node;
 802
 803	node = kzalloc(sizeof(*node), GFP_ATOMIC);
 804	if (node)
 805		xfrm_pol_inexact_node_init(node, addr, prefixlen);
 806
 807	return node;
 808}
 809
 810static int xfrm_policy_addr_delta(const xfrm_address_t *a,
 811				  const xfrm_address_t *b,
 812				  u8 prefixlen, u16 family)
 813{
 814	u32 ma, mb, mask;
 815	unsigned int pdw, pbi;
 816	int delta = 0;
 817
 818	switch (family) {
 819	case AF_INET:
 820		if (prefixlen == 0)
 821			return 0;
 822		mask = ~0U << (32 - prefixlen);
 823		ma = ntohl(a->a4) & mask;
 824		mb = ntohl(b->a4) & mask;
 825		if (ma < mb)
 826			delta = -1;
 827		else if (ma > mb)
 828			delta = 1;
 829		break;
 830	case AF_INET6:
 831		pdw = prefixlen >> 5;
 832		pbi = prefixlen & 0x1f;
 833
 834		if (pdw) {
 835			delta = memcmp(a->a6, b->a6, pdw << 2);
 836			if (delta)
 837				return delta;
 838		}
 839		if (pbi) {
 840			mask = ~0U << (32 - pbi);
 841			ma = ntohl(a->a6[pdw]) & mask;
 842			mb = ntohl(b->a6[pdw]) & mask;
 843			if (ma < mb)
 844				delta = -1;
 845			else if (ma > mb)
 846				delta = 1;
 847		}
 848		break;
 849	default:
 850		break;
 851	}
 852
 853	return delta;
 854}
 855
 856static void xfrm_policy_inexact_list_reinsert(struct net *net,
 857					      struct xfrm_pol_inexact_node *n,
 858					      u16 family)
 859{
 860	unsigned int matched_s, matched_d;
 861	struct xfrm_policy *policy, *p;
 862
 863	matched_s = 0;
 864	matched_d = 0;
 865
 866	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
 867		struct hlist_node *newpos = NULL;
 868		bool matches_s, matches_d;
 869
 870		if (policy->walk.dead || !policy->bydst_reinsert)
 871			continue;
 872
 873		WARN_ON_ONCE(policy->family != family);
 874
 875		policy->bydst_reinsert = false;
 876		hlist_for_each_entry(p, &n->hhead, bydst) {
 877			if (policy->priority > p->priority)
 878				newpos = &p->bydst;
 879			else if (policy->priority == p->priority &&
 880				 policy->pos > p->pos)
 881				newpos = &p->bydst;
 882			else
 883				break;
 884		}
 885
 886		if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
 887			hlist_add_behind_rcu(&policy->bydst, newpos);
 888		else
 889			hlist_add_head_rcu(&policy->bydst, &n->hhead);
 890
 891		/* paranoia checks follow.
 892		 * Check that the reinserted policy matches at least
 893		 * saddr or daddr for current node prefix.
 894		 *
 895		 * Matching both is fine, matching saddr in one policy
 896		 * (but not daddr) and then matching only daddr in another
 897		 * is a bug.
 898		 */
 899		matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
 900						   &n->addr,
 901						   n->prefixlen,
 902						   family) == 0;
 903		matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
 904						   &n->addr,
 905						   n->prefixlen,
 906						   family) == 0;
 907		if (matches_s && matches_d)
 908			continue;
 909
 910		WARN_ON_ONCE(!matches_s && !matches_d);
 911		if (matches_s)
 912			matched_s++;
 913		if (matches_d)
 914			matched_d++;
 915		WARN_ON_ONCE(matched_s && matched_d);
 916	}
 917}
 918
 919static void xfrm_policy_inexact_node_reinsert(struct net *net,
 920					      struct xfrm_pol_inexact_node *n,
 921					      struct rb_root *new,
 922					      u16 family)
 923{
 924	struct xfrm_pol_inexact_node *node;
 925	struct rb_node **p, *parent;
 926
 927	/* we should not have another subtree here */
 928	WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
 929restart:
 930	parent = NULL;
 931	p = &new->rb_node;
 932	while (*p) {
 933		u8 prefixlen;
 934		int delta;
 935
 936		parent = *p;
 937		node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
 938
 939		prefixlen = min(node->prefixlen, n->prefixlen);
 940
 941		delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
 942					       prefixlen, family);
 943		if (delta < 0) {
 944			p = &parent->rb_left;
 945		} else if (delta > 0) {
 946			p = &parent->rb_right;
 947		} else {
 948			bool same_prefixlen = node->prefixlen == n->prefixlen;
 949			struct xfrm_policy *tmp;
 950
 951			hlist_for_each_entry(tmp, &n->hhead, bydst) {
 952				tmp->bydst_reinsert = true;
 953				hlist_del_rcu(&tmp->bydst);
 954			}
 955
 956			node->prefixlen = prefixlen;
 957
 958			xfrm_policy_inexact_list_reinsert(net, node, family);
 959
 960			if (same_prefixlen) {
 961				kfree_rcu(n, rcu);
 962				return;
 963			}
 964
 965			rb_erase(*p, new);
 966			kfree_rcu(n, rcu);
 967			n = node;
 968			goto restart;
 969		}
 970	}
 971
 972	rb_link_node_rcu(&n->node, parent, p);
 973	rb_insert_color(&n->node, new);
 974}
 975
 976/* merge nodes v and n */
 977static void xfrm_policy_inexact_node_merge(struct net *net,
 978					   struct xfrm_pol_inexact_node *v,
 979					   struct xfrm_pol_inexact_node *n,
 980					   u16 family)
 981{
 982	struct xfrm_pol_inexact_node *node;
 983	struct xfrm_policy *tmp;
 984	struct rb_node *rnode;
 985
 986	/* To-be-merged node v has a subtree.
 987	 *
 988	 * Dismantle it and insert its nodes to n->root.
 989	 */
 990	while ((rnode = rb_first(&v->root)) != NULL) {
 991		node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
 992		rb_erase(&node->node, &v->root);
 993		xfrm_policy_inexact_node_reinsert(net, node, &n->root,
 994						  family);
 995	}
 996
 997	hlist_for_each_entry(tmp, &v->hhead, bydst) {
 998		tmp->bydst_reinsert = true;
 999		hlist_del_rcu(&tmp->bydst);
1000	}
1001
1002	xfrm_policy_inexact_list_reinsert(net, n, family);
1003}
1004
1005static struct xfrm_pol_inexact_node *
1006xfrm_policy_inexact_insert_node(struct net *net,
1007				struct rb_root *root,
1008				xfrm_address_t *addr,
1009				u16 family, u8 prefixlen, u8 dir)
1010{
1011	struct xfrm_pol_inexact_node *cached = NULL;
1012	struct rb_node **p, *parent = NULL;
1013	struct xfrm_pol_inexact_node *node;
1014
1015	p = &root->rb_node;
1016	while (*p) {
1017		int delta;
1018
1019		parent = *p;
1020		node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
1021
1022		delta = xfrm_policy_addr_delta(addr, &node->addr,
1023					       node->prefixlen,
1024					       family);
1025		if (delta == 0 && prefixlen >= node->prefixlen) {
1026			WARN_ON_ONCE(cached); /* ipsec policies got lost */
1027			return node;
1028		}
1029
1030		if (delta < 0)
1031			p = &parent->rb_left;
1032		else
1033			p = &parent->rb_right;
1034
1035		if (prefixlen < node->prefixlen) {
1036			delta = xfrm_policy_addr_delta(addr, &node->addr,
1037						       prefixlen,
1038						       family);
1039			if (delta)
1040				continue;
1041
1042			/* This node is a subnet of the new prefix. It needs
1043			 * to be removed and re-inserted with the smaller
1044			 * prefix and all nodes that are now also covered
1045			 * by the reduced prefixlen.
1046			 */
1047			rb_erase(&node->node, root);
1048
1049			if (!cached) {
1050				xfrm_pol_inexact_node_init(node, addr,
1051							   prefixlen);
1052				cached = node;
1053			} else {
1054				/* This node also falls within the new
1055				 * prefixlen. Merge the to-be-reinserted
1056				 * node and this one.
1057				 */
1058				xfrm_policy_inexact_node_merge(net, node,
1059							       cached, family);
1060				kfree_rcu(node, rcu);
1061			}
1062
1063			/* restart */
1064			p = &root->rb_node;
1065			parent = NULL;
1066		}
1067	}
1068
1069	node = cached;
1070	if (!node) {
1071		node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
1072		if (!node)
1073			return NULL;
1074	}
1075
1076	rb_link_node_rcu(&node->node, parent, p);
1077	rb_insert_color(&node->node, root);
1078
1079	return node;
1080}
1081
1082static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
1083{
1084	struct xfrm_pol_inexact_node *node;
1085	struct rb_node *rn = rb_first(r);
1086
1087	while (rn) {
1088		node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
1089
1090		xfrm_policy_inexact_gc_tree(&node->root, rm);
1091		rn = rb_next(rn);
1092
1093		if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
1094			WARN_ON_ONCE(rm);
1095			continue;
1096		}
1097
1098		rb_erase(&node->node, r);
1099		kfree_rcu(node, rcu);
1100	}
1101}
1102
1103static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
1104{
1105	write_seqcount_begin(&b->count);
1106	xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
1107	xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
1108	write_seqcount_end(&b->count);
1109
1110	if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
1111	    !hlist_empty(&b->hhead)) {
1112		WARN_ON_ONCE(net_exit);
1113		return;
1114	}
1115
1116	if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
1117				   xfrm_pol_inexact_params) == 0) {
1118		list_del(&b->inexact_bins);
1119		kfree_rcu(b, rcu);
1120	}
1121}
1122
1123static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
1124{
1125	struct net *net = read_pnet(&b->k.net);
1126
1127	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1128	__xfrm_policy_inexact_prune_bin(b, false);
1129	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1130}
1131
1132static void __xfrm_policy_inexact_flush(struct net *net)
1133{
1134	struct xfrm_pol_inexact_bin *bin, *t;
1135
1136	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1137
1138	list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
1139		__xfrm_policy_inexact_prune_bin(bin, false);
1140}
1141
1142static struct hlist_head *
1143xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
1144				struct xfrm_policy *policy, u8 dir)
1145{
1146	struct xfrm_pol_inexact_node *n;
1147	struct net *net;
1148
1149	net = xp_net(policy);
1150	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1151
1152	if (xfrm_policy_inexact_insert_use_any_list(policy))
1153		return &bin->hhead;
1154
1155	if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
1156					       policy->family,
1157					       policy->selector.prefixlen_d)) {
1158		write_seqcount_begin(&bin->count);
1159		n = xfrm_policy_inexact_insert_node(net,
1160						    &bin->root_s,
1161						    &policy->selector.saddr,
1162						    policy->family,
1163						    policy->selector.prefixlen_s,
1164						    dir);
1165		write_seqcount_end(&bin->count);
1166		if (!n)
1167			return NULL;
1168
1169		return &n->hhead;
1170	}
1171
1172	/* daddr is fixed */
1173	write_seqcount_begin(&bin->count);
1174	n = xfrm_policy_inexact_insert_node(net,
1175					    &bin->root_d,
1176					    &policy->selector.daddr,
1177					    policy->family,
1178					    policy->selector.prefixlen_d, dir);
1179	write_seqcount_end(&bin->count);
1180	if (!n)
1181		return NULL;
1182
1183	/* saddr is wildcard */
1184	if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
1185					       policy->family,
1186					       policy->selector.prefixlen_s))
1187		return &n->hhead;
1188
1189	write_seqcount_begin(&bin->count);
1190	n = xfrm_policy_inexact_insert_node(net,
1191					    &n->root,
1192					    &policy->selector.saddr,
1193					    policy->family,
1194					    policy->selector.prefixlen_s, dir);
1195	write_seqcount_end(&bin->count);
1196	if (!n)
1197		return NULL;
1198
1199	return &n->hhead;
1200}
1201
1202static struct xfrm_policy *
1203xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
1204{
1205	struct xfrm_pol_inexact_bin *bin;
1206	struct xfrm_policy *delpol;
1207	struct hlist_head *chain;
1208	struct net *net;
1209
1210	bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1211	if (!bin)
1212		return ERR_PTR(-ENOMEM);
1213
1214	net = xp_net(policy);
1215	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
1216
1217	chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
1218	if (!chain) {
1219		__xfrm_policy_inexact_prune_bin(bin, false);
1220		return ERR_PTR(-ENOMEM);
1221	}
1222
1223	delpol = xfrm_policy_insert_list(chain, policy, excl);
1224	if (delpol && excl) {
1225		__xfrm_policy_inexact_prune_bin(bin, false);
1226		return ERR_PTR(-EEXIST);
1227	}
1228
1229	chain = &net->xfrm.policy_inexact[dir];
1230	xfrm_policy_insert_inexact_list(chain, policy);
1231
1232	if (delpol)
1233		__xfrm_policy_inexact_prune_bin(bin, false);
1234
1235	return delpol;
1236}
1237
1238static void xfrm_hash_rebuild(struct work_struct *work)
1239{
1240	struct net *net = container_of(work, struct net,
1241				       xfrm.policy_hthresh.work);
1242	unsigned int hmask;
1243	struct xfrm_policy *pol;
1244	struct xfrm_policy *policy;
1245	struct hlist_head *chain;
1246	struct hlist_head *odst;
1247	struct hlist_node *newpos;
1248	int i;
1249	int dir;
1250	unsigned seq;
1251	u8 lbits4, rbits4, lbits6, rbits6;
1252
1253	mutex_lock(&hash_resize_mutex);
1254
1255	/* read selector prefixlen thresholds */
1256	do {
1257		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
1258
1259		lbits4 = net->xfrm.policy_hthresh.lbits4;
1260		rbits4 = net->xfrm.policy_hthresh.rbits4;
1261		lbits6 = net->xfrm.policy_hthresh.lbits6;
1262		rbits6 = net->xfrm.policy_hthresh.rbits6;
1263	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
1264
1265	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1266	write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
1267
1268	/* make sure that we can insert the indirect policies again before
1269	 * we start with destructive action.
1270	 */
1271	list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
1272		struct xfrm_pol_inexact_bin *bin;
1273		u8 dbits, sbits;
1274
1275		if (policy->walk.dead)
1276			continue;
1277
1278		dir = xfrm_policy_id2dir(policy->index);
1279		if (dir >= XFRM_POLICY_MAX)
1280			continue;
1281
1282		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1283			if (policy->family == AF_INET) {
1284				dbits = rbits4;
1285				sbits = lbits4;
1286			} else {
1287				dbits = rbits6;
1288				sbits = lbits6;
1289			}
1290		} else {
1291			if (policy->family == AF_INET) {
1292				dbits = lbits4;
1293				sbits = rbits4;
1294			} else {
1295				dbits = lbits6;
1296				sbits = rbits6;
1297			}
1298		}
1299
1300		if (policy->selector.prefixlen_d < dbits ||
1301		    policy->selector.prefixlen_s < sbits)
1302			continue;
1303
1304		bin = xfrm_policy_inexact_alloc_bin(policy, dir);
1305		if (!bin)
1306			goto out_unlock;
1307
1308		if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
1309			goto out_unlock;
1310	}
1311
1312	/* reset the bydst and inexact table in all directions */
1313	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
1314		struct hlist_node *n;
1315
1316		hlist_for_each_entry_safe(policy, n,
1317					  &net->xfrm.policy_inexact[dir],
1318					  bydst_inexact_list) {
1319			hlist_del_rcu(&policy->bydst);
1320			hlist_del_init(&policy->bydst_inexact_list);
1321		}
1322
1323		hmask = net->xfrm.policy_bydst[dir].hmask;
1324		odst = net->xfrm.policy_bydst[dir].table;
1325		for (i = hmask; i >= 0; i--) {
1326			hlist_for_each_entry_safe(policy, n, odst + i, bydst)
1327				hlist_del_rcu(&policy->bydst);
1328		}
1329		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
1330			/* dir out => dst = remote, src = local */
1331			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
1332			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
1333			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
1334			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
1335		} else {
1336			/* dir in/fwd => dst = local, src = remote */
1337			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
1338			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
1339			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
1340			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
1341		}
1342	}
1343
1344	/* re-insert all policies by order of creation */
1345	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
1346		if (policy->walk.dead)
1347			continue;
1348		dir = xfrm_policy_id2dir(policy->index);
1349		if (dir >= XFRM_POLICY_MAX) {
1350			/* skip socket policies */
1351			continue;
1352		}
1353		newpos = NULL;
1354		chain = policy_hash_bysel(net, &policy->selector,
1355					  policy->family, dir);
1356
1357		if (!chain) {
1358			void *p = xfrm_policy_inexact_insert(policy, dir, 0);
1359
1360			WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
1361			continue;
1362		}
1363
1364		hlist_for_each_entry(pol, chain, bydst) {
1365			if (policy->priority >= pol->priority)
1366				newpos = &pol->bydst;
1367			else
1368				break;
1369		}
1370		if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1371			hlist_add_behind_rcu(&policy->bydst, newpos);
1372		else
1373			hlist_add_head_rcu(&policy->bydst, chain);
1374	}
1375
1376out_unlock:
1377	__xfrm_policy_inexact_flush(net);
1378	write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
1379	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1380
1381	mutex_unlock(&hash_resize_mutex);
1382}
1383
1384void xfrm_policy_hash_rebuild(struct net *net)
1385{
1386	schedule_work(&net->xfrm.policy_hthresh.work);
1387}
1388EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
1389
1390/* Generate new index... KAME seems to generate them ordered by cost
1391 * of an absolute inpredictability of ordering of rules. This will not pass. */
1392static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
1393{
 
 
1394	for (;;) {
1395		struct hlist_head *list;
1396		struct xfrm_policy *p;
1397		u32 idx;
1398		int found;
1399
1400		if (!index) {
1401			idx = (net->xfrm.idx_generator | dir);
1402			net->xfrm.idx_generator += 8;
1403		} else {
1404			idx = index;
1405			index = 0;
1406		}
1407
1408		if (idx == 0)
1409			idx = 8;
1410		list = net->xfrm.policy_byidx + idx_hash(net, idx);
1411		found = 0;
1412		hlist_for_each_entry(p, list, byidx) {
1413			if (p->index == idx) {
1414				found = 1;
1415				break;
1416			}
1417		}
1418		if (!found)
1419			return idx;
1420	}
1421}
1422
1423static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
1424{
1425	u32 *p1 = (u32 *) s1;
1426	u32 *p2 = (u32 *) s2;
1427	int len = sizeof(struct xfrm_selector) / sizeof(u32);
1428	int i;
1429
1430	for (i = 0; i < len; i++) {
1431		if (p1[i] != p2[i])
1432			return 1;
1433	}
1434
1435	return 0;
1436}
1437
1438static void xfrm_policy_requeue(struct xfrm_policy *old,
1439				struct xfrm_policy *new)
1440{
1441	struct xfrm_policy_queue *pq = &old->polq;
1442	struct sk_buff_head list;
1443
1444	if (skb_queue_empty(&pq->hold_queue))
1445		return;
1446
1447	__skb_queue_head_init(&list);
1448
1449	spin_lock_bh(&pq->hold_queue.lock);
1450	skb_queue_splice_init(&pq->hold_queue, &list);
1451	if (del_timer(&pq->hold_timer))
1452		xfrm_pol_put(old);
1453	spin_unlock_bh(&pq->hold_queue.lock);
1454
1455	pq = &new->polq;
1456
1457	spin_lock_bh(&pq->hold_queue.lock);
1458	skb_queue_splice(&list, &pq->hold_queue);
1459	pq->timeout = XFRM_QUEUE_TMO_MIN;
1460	if (!mod_timer(&pq->hold_timer, jiffies))
1461		xfrm_pol_hold(new);
1462	spin_unlock_bh(&pq->hold_queue.lock);
1463}
1464
1465static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
1466					  struct xfrm_policy *pol)
1467{
1468	return mark->v == pol->mark.v && mark->m == pol->mark.m;
 
 
 
 
 
 
 
 
 
1469}
1470
1471static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
1472{
1473	const struct xfrm_pol_inexact_key *k = data;
1474	u32 a = k->type << 24 | k->dir << 16 | k->family;
1475
1476	return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
1477			    seed);
1478}
1479
1480static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
1481{
1482	const struct xfrm_pol_inexact_bin *b = data;
1483
1484	return xfrm_pol_bin_key(&b->k, 0, seed);
1485}
1486
1487static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
1488			    const void *ptr)
1489{
1490	const struct xfrm_pol_inexact_key *key = arg->key;
1491	const struct xfrm_pol_inexact_bin *b = ptr;
1492	int ret;
1493
1494	if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
1495		return -1;
1496
1497	ret = b->k.dir ^ key->dir;
1498	if (ret)
1499		return ret;
1500
1501	ret = b->k.type ^ key->type;
1502	if (ret)
1503		return ret;
1504
1505	ret = b->k.family ^ key->family;
1506	if (ret)
1507		return ret;
1508
1509	return b->k.if_id ^ key->if_id;
1510}
1511
1512static const struct rhashtable_params xfrm_pol_inexact_params = {
1513	.head_offset		= offsetof(struct xfrm_pol_inexact_bin, head),
1514	.hashfn			= xfrm_pol_bin_key,
1515	.obj_hashfn		= xfrm_pol_bin_obj,
1516	.obj_cmpfn		= xfrm_pol_bin_cmp,
1517	.automatic_shrinking	= true,
1518};
1519
1520static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
1521					    struct xfrm_policy *policy)
1522{
1523	struct xfrm_policy *pol, *delpol = NULL;
1524	struct hlist_node *newpos = NULL;
1525	int i = 0;
1526
1527	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1528		if (pol->type == policy->type &&
1529		    pol->if_id == policy->if_id &&
1530		    !selector_cmp(&pol->selector, &policy->selector) &&
1531		    xfrm_policy_mark_match(&policy->mark, pol) &&
1532		    xfrm_sec_ctx_match(pol->security, policy->security) &&
1533		    !WARN_ON(delpol)) {
1534			delpol = pol;
1535			if (policy->priority > pol->priority)
1536				continue;
1537		} else if (policy->priority >= pol->priority) {
1538			newpos = &pol->bydst_inexact_list;
1539			continue;
1540		}
1541		if (delpol)
1542			break;
1543	}
1544
1545	if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1546		hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
1547	else
1548		hlist_add_head_rcu(&policy->bydst_inexact_list, chain);
1549
1550	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
1551		pol->pos = i;
1552		i++;
1553	}
1554}
1555
1556static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
1557						   struct xfrm_policy *policy,
1558						   bool excl)
1559{
1560	struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
1561
1562	hlist_for_each_entry(pol, chain, bydst) {
1563		if (pol->type == policy->type &&
1564		    pol->if_id == policy->if_id &&
1565		    !selector_cmp(&pol->selector, &policy->selector) &&
1566		    xfrm_policy_mark_match(&policy->mark, pol) &&
1567		    xfrm_sec_ctx_match(pol->security, policy->security) &&
1568		    !WARN_ON(delpol)) {
1569			if (excl)
1570				return ERR_PTR(-EEXIST);
1571			delpol = pol;
1572			if (policy->priority > pol->priority)
1573				continue;
1574		} else if (policy->priority >= pol->priority) {
1575			newpos = pol;
1576			continue;
1577		}
1578		if (delpol)
1579			break;
1580	}
1581
1582	if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
1583		hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
1584	else
1585		/* Packet offload policies enter to the head
1586		 * to speed-up lookups.
1587		 */
1588		hlist_add_head_rcu(&policy->bydst, chain);
1589
1590	return delpol;
1591}
1592
1593int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
1594{
1595	struct net *net = xp_net(policy);
1596	struct xfrm_policy *delpol;
1597	struct hlist_head *chain;
1598
1599	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1600	chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
1601	if (chain)
1602		delpol = xfrm_policy_insert_list(chain, policy, excl);
1603	else
1604		delpol = xfrm_policy_inexact_insert(policy, dir, excl);
1605
1606	if (IS_ERR(delpol)) {
1607		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1608		return PTR_ERR(delpol);
1609	}
1610
1611	__xfrm_policy_link(policy, dir);
1612
1613	/* After previous checking, family can either be AF_INET or AF_INET6 */
1614	if (policy->family == AF_INET)
1615		rt_genid_bump_ipv4(net);
1616	else
1617		rt_genid_bump_ipv6(net);
1618
1619	if (delpol) {
1620		xfrm_policy_requeue(delpol, policy);
1621		__xfrm_policy_unlink(delpol, dir);
1622	}
1623	policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
1624	hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
1625	policy->curlft.add_time = ktime_get_real_seconds();
1626	policy->curlft.use_time = 0;
1627	if (!mod_timer(&policy->timer, jiffies + HZ))
1628		xfrm_pol_hold(policy);
1629	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1630
1631	if (delpol)
1632		xfrm_policy_kill(delpol);
1633	else if (xfrm_bydst_should_resize(net, dir, NULL))
1634		schedule_work(&net->xfrm.policy_hash_work);
1635
1636	return 0;
1637}
1638EXPORT_SYMBOL(xfrm_policy_insert);
1639
1640static struct xfrm_policy *
1641__xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
1642			u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
 
1643			struct xfrm_sec_ctx *ctx)
1644{
1645	struct xfrm_policy *pol;
1646
1647	if (!chain)
1648		return NULL;
1649
1650	hlist_for_each_entry(pol, chain, bydst) {
1651		if (pol->type == type &&
1652		    pol->if_id == if_id &&
1653		    xfrm_policy_mark_match(mark, pol) &&
1654		    !selector_cmp(sel, &pol->selector) &&
1655		    xfrm_sec_ctx_match(ctx, pol->security))
1656			return pol;
1657	}
1658
1659	return NULL;
1660}
1661
1662struct xfrm_policy *
1663xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1664		      u8 type, int dir, struct xfrm_selector *sel,
1665		      struct xfrm_sec_ctx *ctx, int delete, int *err)
 
1666{
1667	struct xfrm_pol_inexact_bin *bin = NULL;
1668	struct xfrm_policy *pol, *ret = NULL;
1669	struct hlist_head *chain;
1670
1671	*err = 0;
1672	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1673	chain = policy_hash_bysel(net, sel, sel->family, dir);
1674	if (!chain) {
1675		struct xfrm_pol_inexact_candidates cand;
1676		int i;
1677
1678		bin = xfrm_policy_inexact_lookup(net, type,
1679						 sel->family, dir, if_id);
1680		if (!bin) {
1681			spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1682			return NULL;
1683		}
1684
1685		if (!xfrm_policy_find_inexact_candidates(&cand, bin,
1686							 &sel->saddr,
1687							 &sel->daddr)) {
1688			spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1689			return NULL;
1690		}
1691
1692		pol = NULL;
1693		for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
1694			struct xfrm_policy *tmp;
1695
1696			tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
1697						      if_id, type, dir,
1698						      sel, ctx);
1699			if (!tmp)
1700				continue;
1701
1702			if (!pol || tmp->pos < pol->pos)
1703				pol = tmp;
1704		}
1705	} else {
1706		pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
1707					      sel, ctx);
1708	}
1709
1710	if (pol) {
1711		xfrm_pol_hold(pol);
1712		if (delete) {
1713			*err = security_xfrm_policy_delete(pol->security);
1714			if (*err) {
1715				spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1716				return pol;
1717			}
1718			__xfrm_policy_unlink(pol, dir);
1719		}
1720		ret = pol;
1721	}
1722	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1723
1724	if (ret && delete)
1725		xfrm_policy_kill(ret);
1726	if (bin && delete)
1727		xfrm_policy_inexact_prune_bin(bin);
1728	return ret;
1729}
1730EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
1731
1732struct xfrm_policy *
1733xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
1734		 u8 type, int dir, u32 id, int delete, int *err)
1735{
1736	struct xfrm_policy *pol, *ret;
1737	struct hlist_head *chain;
1738
1739	*err = -ENOENT;
1740	if (xfrm_policy_id2dir(id) != dir)
1741		return NULL;
1742
1743	*err = 0;
1744	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1745	chain = net->xfrm.policy_byidx + idx_hash(net, id);
1746	ret = NULL;
1747	hlist_for_each_entry(pol, chain, byidx) {
1748		if (pol->type == type && pol->index == id &&
1749		    pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
 
1750			xfrm_pol_hold(pol);
1751			if (delete) {
1752				*err = security_xfrm_policy_delete(
1753								pol->security);
1754				if (*err) {
1755					spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1756					return pol;
1757				}
1758				__xfrm_policy_unlink(pol, dir);
1759			}
1760			ret = pol;
1761			break;
1762		}
1763	}
1764	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1765
1766	if (ret && delete)
1767		xfrm_policy_kill(ret);
1768	return ret;
1769}
1770EXPORT_SYMBOL(xfrm_policy_byid);
1771
1772#ifdef CONFIG_SECURITY_NETWORK_XFRM
1773static inline int
1774xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1775{
1776	struct xfrm_policy *pol;
1777	int err = 0;
1778
1779	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1780		if (pol->walk.dead ||
1781		    xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1782		    pol->type != type)
1783			continue;
1784
1785		err = security_xfrm_policy_delete(pol->security);
1786		if (err) {
1787			xfrm_audit_policy_delete(pol, 0, task_valid);
1788			return err;
1789		}
1790	}
1791	return err;
1792}
1793
1794static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1795						     struct net_device *dev,
1796						     bool task_valid)
1797{
1798	struct xfrm_policy *pol;
1799	int err = 0;
1800
1801	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1802		if (pol->walk.dead ||
1803		    xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
1804		    pol->xdo.dev != dev)
1805			continue;
1806
1807		err = security_xfrm_policy_delete(pol->security);
1808		if (err) {
1809			xfrm_audit_policy_delete(pol, 0, task_valid);
1810			return err;
1811		}
1812	}
1813	return err;
1814}
1815#else
1816static inline int
1817xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
1818{
1819	return 0;
1820}
1821
1822static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
1823						     struct net_device *dev,
1824						     bool task_valid)
1825{
1826	return 0;
1827}
1828#endif
1829
1830int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
1831{
1832	int dir, err = 0, cnt = 0;
1833	struct xfrm_policy *pol;
1834
1835	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1836
1837	err = xfrm_policy_flush_secctx_check(net, type, task_valid);
1838	if (err)
1839		goto out;
1840
1841again:
1842	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1843		if (pol->walk.dead)
1844			continue;
1845
1846		dir = xfrm_policy_id2dir(pol->index);
1847		if (dir >= XFRM_POLICY_MAX ||
 
1848		    pol->type != type)
1849			continue;
1850
1851		__xfrm_policy_unlink(pol, dir);
1852		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1853		xfrm_dev_policy_delete(pol);
1854		cnt++;
1855		xfrm_audit_policy_delete(pol, 1, task_valid);
1856		xfrm_policy_kill(pol);
1857		spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1858		goto again;
1859	}
1860	if (cnt)
1861		__xfrm_policy_inexact_flush(net);
1862	else
1863		err = -ESRCH;
1864out:
1865	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1866	return err;
1867}
1868EXPORT_SYMBOL(xfrm_policy_flush);
1869
1870int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
1871			  bool task_valid)
1872{
1873	int dir, err = 0, cnt = 0;
1874	struct xfrm_policy *pol;
1875
1876	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1877
1878	err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
1879	if (err)
1880		goto out;
1881
1882again:
1883	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
1884		if (pol->walk.dead)
1885			continue;
1886
1887		dir = xfrm_policy_id2dir(pol->index);
1888		if (dir >= XFRM_POLICY_MAX ||
1889		    pol->xdo.dev != dev)
1890			continue;
1891
1892		__xfrm_policy_unlink(pol, dir);
1893		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1894		xfrm_dev_policy_delete(pol);
1895		cnt++;
1896		xfrm_audit_policy_delete(pol, 1, task_valid);
1897		xfrm_policy_kill(pol);
1898		spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1899		goto again;
1900	}
1901	if (cnt)
1902		__xfrm_policy_inexact_flush(net);
1903	else
1904		err = -ESRCH;
1905out:
1906	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1907	return err;
1908}
1909EXPORT_SYMBOL(xfrm_dev_policy_flush);
1910
1911int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1912		     int (*func)(struct xfrm_policy *, int, int, void*),
1913		     void *data)
1914{
1915	struct xfrm_policy *pol;
1916	struct xfrm_policy_walk_entry *x;
1917	int error = 0;
1918
1919	if (walk->type >= XFRM_POLICY_TYPE_MAX &&
1920	    walk->type != XFRM_POLICY_TYPE_ANY)
1921		return -EINVAL;
1922
1923	if (list_empty(&walk->walk.all) && walk->seq != 0)
1924		return 0;
1925
1926	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
1927	if (list_empty(&walk->walk.all))
1928		x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
1929	else
1930		x = list_first_entry(&walk->walk.all,
1931				     struct xfrm_policy_walk_entry, all);
1932
1933	list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
1934		if (x->dead)
1935			continue;
1936		pol = container_of(x, struct xfrm_policy, walk);
1937		if (walk->type != XFRM_POLICY_TYPE_ANY &&
1938		    walk->type != pol->type)
1939			continue;
1940		error = func(pol, xfrm_policy_id2dir(pol->index),
1941			     walk->seq, data);
1942		if (error) {
1943			list_move_tail(&walk->walk.all, &x->all);
1944			goto out;
1945		}
1946		walk->seq++;
1947	}
1948	if (walk->seq == 0) {
1949		error = -ENOENT;
1950		goto out;
1951	}
1952	list_del_init(&walk->walk.all);
1953out:
1954	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1955	return error;
1956}
1957EXPORT_SYMBOL(xfrm_policy_walk);
1958
1959void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
1960{
1961	INIT_LIST_HEAD(&walk->walk.all);
1962	walk->walk.dead = 1;
1963	walk->type = type;
1964	walk->seq = 0;
1965}
1966EXPORT_SYMBOL(xfrm_policy_walk_init);
1967
1968void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
1969{
1970	if (list_empty(&walk->walk.all))
1971		return;
1972
1973	spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
1974	list_del(&walk->walk.all);
1975	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
1976}
1977EXPORT_SYMBOL(xfrm_policy_walk_done);
1978
1979/*
1980 * Find policy to apply to this flow.
1981 *
1982 * Returns 0 if policy found, else an -errno.
1983 */
1984static int xfrm_policy_match(const struct xfrm_policy *pol,
1985			     const struct flowi *fl,
1986			     u8 type, u16 family, u32 if_id)
1987{
1988	const struct xfrm_selector *sel = &pol->selector;
1989	int ret = -ESRCH;
1990	bool match;
1991
1992	if (pol->family != family ||
1993	    pol->if_id != if_id ||
1994	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
1995	    pol->type != type)
1996		return ret;
1997
1998	match = xfrm_selector_match(sel, fl, family);
1999	if (match)
2000		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
 
2001	return ret;
2002}
2003
2004static struct xfrm_pol_inexact_node *
2005xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
2006				seqcount_spinlock_t *count,
2007				const xfrm_address_t *addr, u16 family)
2008{
2009	const struct rb_node *parent;
2010	int seq;
2011
2012again:
2013	seq = read_seqcount_begin(count);
2014
2015	parent = rcu_dereference_raw(r->rb_node);
2016	while (parent) {
2017		struct xfrm_pol_inexact_node *node;
2018		int delta;
2019
2020		node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
2021
2022		delta = xfrm_policy_addr_delta(addr, &node->addr,
2023					       node->prefixlen, family);
2024		if (delta < 0) {
2025			parent = rcu_dereference_raw(parent->rb_left);
2026			continue;
2027		} else if (delta > 0) {
2028			parent = rcu_dereference_raw(parent->rb_right);
2029			continue;
2030		}
2031
2032		return node;
2033	}
2034
2035	if (read_seqcount_retry(count, seq))
2036		goto again;
2037
2038	return NULL;
2039}
2040
2041static bool
2042xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
2043				    struct xfrm_pol_inexact_bin *b,
2044				    const xfrm_address_t *saddr,
2045				    const xfrm_address_t *daddr)
2046{
2047	struct xfrm_pol_inexact_node *n;
2048	u16 family;
2049
2050	if (!b)
2051		return false;
2052
2053	family = b->k.family;
2054	memset(cand, 0, sizeof(*cand));
2055	cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
2056
2057	n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
2058					    family);
2059	if (n) {
2060		cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
2061		n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
2062						    family);
2063		if (n)
2064			cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
2065	}
2066
2067	n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
2068					    family);
2069	if (n)
2070		cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
2071
2072	return true;
2073}
2074
2075static struct xfrm_pol_inexact_bin *
2076xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
2077			       u8 dir, u32 if_id)
2078{
2079	struct xfrm_pol_inexact_key k = {
2080		.family = family,
2081		.type = type,
2082		.dir = dir,
2083		.if_id = if_id,
2084	};
2085
2086	write_pnet(&k.net, net);
2087
2088	return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
2089				 xfrm_pol_inexact_params);
2090}
2091
2092static struct xfrm_pol_inexact_bin *
2093xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
2094			   u8 dir, u32 if_id)
2095{
2096	struct xfrm_pol_inexact_bin *bin;
2097
2098	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
2099
2100	rcu_read_lock();
2101	bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2102	rcu_read_unlock();
2103
2104	return bin;
2105}
2106
2107static struct xfrm_policy *
2108__xfrm_policy_eval_candidates(struct hlist_head *chain,
2109			      struct xfrm_policy *prefer,
2110			      const struct flowi *fl,
2111			      u8 type, u16 family, u32 if_id)
2112{
2113	u32 priority = prefer ? prefer->priority : ~0u;
2114	struct xfrm_policy *pol;
2115
2116	if (!chain)
2117		return NULL;
2118
2119	hlist_for_each_entry_rcu(pol, chain, bydst) {
2120		int err;
2121
2122		if (pol->priority > priority)
2123			break;
2124
2125		err = xfrm_policy_match(pol, fl, type, family, if_id);
2126		if (err) {
2127			if (err != -ESRCH)
2128				return ERR_PTR(err);
2129
2130			continue;
2131		}
2132
2133		if (prefer) {
2134			/* matches.  Is it older than *prefer? */
2135			if (pol->priority == priority &&
2136			    prefer->pos < pol->pos)
2137				return prefer;
2138		}
2139
2140		return pol;
2141	}
2142
2143	return NULL;
2144}
2145
2146static struct xfrm_policy *
2147xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
2148			    struct xfrm_policy *prefer,
2149			    const struct flowi *fl,
2150			    u8 type, u16 family, u32 if_id)
2151{
2152	struct xfrm_policy *tmp;
2153	int i;
2154
2155	for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
2156		tmp = __xfrm_policy_eval_candidates(cand->res[i],
2157						    prefer,
2158						    fl, type, family, if_id);
 
2159		if (!tmp)
2160			continue;
2161
2162		if (IS_ERR(tmp))
2163			return tmp;
2164		prefer = tmp;
2165	}
2166
2167	return prefer;
2168}
2169
2170static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
2171						     const struct flowi *fl,
2172						     u16 family, u8 dir,
2173						     u32 if_id)
2174{
2175	struct xfrm_pol_inexact_candidates cand;
2176	const xfrm_address_t *daddr, *saddr;
2177	struct xfrm_pol_inexact_bin *bin;
2178	struct xfrm_policy *pol, *ret;
2179	struct hlist_head *chain;
2180	unsigned int sequence;
2181	int err;
2182
2183	daddr = xfrm_flowi_daddr(fl, family);
2184	saddr = xfrm_flowi_saddr(fl, family);
2185	if (unlikely(!daddr || !saddr))
2186		return NULL;
2187
2188	rcu_read_lock();
2189 retry:
2190	do {
2191		sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
2192		chain = policy_hash_direct(net, daddr, saddr, family, dir);
2193	} while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
2194
2195	ret = NULL;
2196	hlist_for_each_entry_rcu(pol, chain, bydst) {
2197		err = xfrm_policy_match(pol, fl, type, family, if_id);
2198		if (err) {
2199			if (err == -ESRCH)
2200				continue;
2201			else {
2202				ret = ERR_PTR(err);
2203				goto fail;
2204			}
2205		} else {
2206			ret = pol;
2207			break;
2208		}
2209	}
2210	if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
2211		goto skip_inexact;
2212
2213	bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
2214	if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
2215							 daddr))
2216		goto skip_inexact;
2217
2218	pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
2219					  family, if_id);
2220	if (pol) {
2221		ret = pol;
2222		if (IS_ERR(pol))
2223			goto fail;
2224	}
2225
2226skip_inexact:
2227	if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
2228		goto retry;
2229
2230	if (ret && !xfrm_pol_hold_rcu(ret))
2231		goto retry;
2232fail:
2233	rcu_read_unlock();
2234
2235	return ret;
2236}
2237
2238static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
2239					      const struct flowi *fl,
2240					      u16 family, u8 dir, u32 if_id)
2241{
2242#ifdef CONFIG_XFRM_SUB_POLICY
2243	struct xfrm_policy *pol;
2244
2245	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
2246					dir, if_id);
2247	if (pol != NULL)
2248		return pol;
2249#endif
2250	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
2251					 dir, if_id);
2252}
2253
2254static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
2255						 const struct flowi *fl,
2256						 u16 family, u32 if_id)
2257{
2258	struct xfrm_policy *pol;
2259
2260	rcu_read_lock();
2261 again:
2262	pol = rcu_dereference(sk->sk_policy[dir]);
2263	if (pol != NULL) {
2264		bool match;
2265		int err = 0;
2266
2267		if (pol->family != family) {
2268			pol = NULL;
2269			goto out;
2270		}
2271
2272		match = xfrm_selector_match(&pol->selector, fl, family);
2273		if (match) {
2274			if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v ||
2275			    pol->if_id != if_id) {
2276				pol = NULL;
2277				goto out;
2278			}
2279			err = security_xfrm_policy_lookup(pol->security,
2280						      fl->flowi_secid);
 
2281			if (!err) {
2282				if (!xfrm_pol_hold_rcu(pol))
2283					goto again;
2284			} else if (err == -ESRCH) {
2285				pol = NULL;
2286			} else {
2287				pol = ERR_PTR(err);
2288			}
2289		} else
2290			pol = NULL;
2291	}
2292out:
2293	rcu_read_unlock();
2294	return pol;
2295}
2296
2297static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
2298{
2299	struct net *net = xp_net(pol);
2300
2301	list_add(&pol->walk.all, &net->xfrm.policy_all);
2302	net->xfrm.policy_count[dir]++;
2303	xfrm_pol_hold(pol);
2304}
2305
2306static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
2307						int dir)
2308{
2309	struct net *net = xp_net(pol);
2310
2311	if (list_empty(&pol->walk.all))
2312		return NULL;
2313
2314	/* Socket policies are not hashed. */
2315	if (!hlist_unhashed(&pol->bydst)) {
2316		hlist_del_rcu(&pol->bydst);
2317		hlist_del_init(&pol->bydst_inexact_list);
2318		hlist_del(&pol->byidx);
2319	}
2320
2321	list_del_init(&pol->walk.all);
2322	net->xfrm.policy_count[dir]--;
2323
2324	return pol;
2325}
2326
2327static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
2328{
2329	__xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
2330}
2331
2332static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
2333{
2334	__xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
2335}
2336
2337int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
2338{
2339	struct net *net = xp_net(pol);
2340
2341	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2342	pol = __xfrm_policy_unlink(pol, dir);
2343	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2344	if (pol) {
2345		xfrm_dev_policy_delete(pol);
2346		xfrm_policy_kill(pol);
2347		return 0;
2348	}
2349	return -ENOENT;
2350}
2351EXPORT_SYMBOL(xfrm_policy_delete);
2352
2353int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
2354{
2355	struct net *net = sock_net(sk);
2356	struct xfrm_policy *old_pol;
2357
2358#ifdef CONFIG_XFRM_SUB_POLICY
2359	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
2360		return -EINVAL;
2361#endif
2362
2363	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2364	old_pol = rcu_dereference_protected(sk->sk_policy[dir],
2365				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
2366	if (pol) {
2367		pol->curlft.add_time = ktime_get_real_seconds();
2368		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
2369		xfrm_sk_policy_link(pol, dir);
2370	}
2371	rcu_assign_pointer(sk->sk_policy[dir], pol);
2372	if (old_pol) {
2373		if (pol)
2374			xfrm_policy_requeue(old_pol, pol);
2375
2376		/* Unlinking succeeds always. This is the only function
2377		 * allowed to delete or replace socket policy.
2378		 */
2379		xfrm_sk_policy_unlink(old_pol, dir);
2380	}
2381	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2382
2383	if (old_pol) {
2384		xfrm_policy_kill(old_pol);
2385	}
2386	return 0;
2387}
2388
2389static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
2390{
2391	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
2392	struct net *net = xp_net(old);
2393
2394	if (newp) {
2395		newp->selector = old->selector;
2396		if (security_xfrm_policy_clone(old->security,
2397					       &newp->security)) {
2398			kfree(newp);
2399			return NULL;  /* ENOMEM */
2400		}
2401		newp->lft = old->lft;
2402		newp->curlft = old->curlft;
2403		newp->mark = old->mark;
2404		newp->if_id = old->if_id;
2405		newp->action = old->action;
2406		newp->flags = old->flags;
2407		newp->xfrm_nr = old->xfrm_nr;
2408		newp->index = old->index;
2409		newp->type = old->type;
2410		newp->family = old->family;
2411		memcpy(newp->xfrm_vec, old->xfrm_vec,
2412		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
2413		spin_lock_bh(&net->xfrm.xfrm_policy_lock);
2414		xfrm_sk_policy_link(newp, dir);
2415		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
2416		xfrm_pol_put(newp);
2417	}
2418	return newp;
2419}
2420
2421int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
2422{
2423	const struct xfrm_policy *p;
2424	struct xfrm_policy *np;
2425	int i, ret = 0;
2426
2427	rcu_read_lock();
2428	for (i = 0; i < 2; i++) {
2429		p = rcu_dereference(osk->sk_policy[i]);
2430		if (p) {
2431			np = clone_policy(p, i);
2432			if (unlikely(!np)) {
2433				ret = -ENOMEM;
2434				break;
2435			}
2436			rcu_assign_pointer(sk->sk_policy[i], np);
2437		}
2438	}
2439	rcu_read_unlock();
2440	return ret;
2441}
2442
2443static int
2444xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
2445	       xfrm_address_t *remote, unsigned short family, u32 mark)
2446{
2447	int err;
2448	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2449
2450	if (unlikely(afinfo == NULL))
2451		return -EINVAL;
2452	err = afinfo->get_saddr(net, oif, local, remote, mark);
2453	rcu_read_unlock();
2454	return err;
2455}
2456
2457/* Resolve list of templates for the flow, given policy. */
2458
2459static int
2460xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
2461		      struct xfrm_state **xfrm, unsigned short family)
2462{
2463	struct net *net = xp_net(policy);
2464	int nx;
2465	int i, error;
2466	xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
2467	xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
2468	xfrm_address_t tmp;
2469
2470	for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
2471		struct xfrm_state *x;
2472		xfrm_address_t *remote = daddr;
2473		xfrm_address_t *local  = saddr;
2474		struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
2475
2476		if (tmpl->mode == XFRM_MODE_TUNNEL ||
2477		    tmpl->mode == XFRM_MODE_BEET) {
2478			remote = &tmpl->id.daddr;
2479			local = &tmpl->saddr;
2480			if (xfrm_addr_any(local, tmpl->encap_family)) {
2481				error = xfrm_get_saddr(net, fl->flowi_oif,
2482						       &tmp, remote,
2483						       tmpl->encap_family, 0);
2484				if (error)
2485					goto fail;
2486				local = &tmp;
2487			}
2488		}
2489
2490		x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
2491				    family, policy->if_id);
2492
2493		if (x && x->km.state == XFRM_STATE_VALID) {
2494			xfrm[nx++] = x;
2495			daddr = remote;
2496			saddr = local;
2497			continue;
2498		}
2499		if (x) {
2500			error = (x->km.state == XFRM_STATE_ERROR ?
2501				 -EINVAL : -EAGAIN);
2502			xfrm_state_put(x);
2503		} else if (error == -ESRCH) {
2504			error = -EAGAIN;
2505		}
2506
2507		if (!tmpl->optional)
2508			goto fail;
2509	}
2510	return nx;
2511
2512fail:
2513	for (nx--; nx >= 0; nx--)
2514		xfrm_state_put(xfrm[nx]);
2515	return error;
2516}
2517
2518static int
2519xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
2520		  struct xfrm_state **xfrm, unsigned short family)
2521{
2522	struct xfrm_state *tp[XFRM_MAX_DEPTH];
2523	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
2524	int cnx = 0;
2525	int error;
2526	int ret;
2527	int i;
2528
2529	for (i = 0; i < npols; i++) {
2530		if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
2531			error = -ENOBUFS;
2532			goto fail;
2533		}
2534
2535		ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
2536		if (ret < 0) {
2537			error = ret;
2538			goto fail;
2539		} else
2540			cnx += ret;
2541	}
2542
2543	/* found states are sorted for outbound processing */
2544	if (npols > 1)
2545		xfrm_state_sort(xfrm, tpp, cnx, family);
2546
2547	return cnx;
2548
2549 fail:
2550	for (cnx--; cnx >= 0; cnx--)
2551		xfrm_state_put(tpp[cnx]);
2552	return error;
2553
2554}
2555
2556static int xfrm_get_tos(const struct flowi *fl, int family)
2557{
2558	if (family == AF_INET)
2559		return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;
2560
2561	return 0;
2562}
2563
2564static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
2565{
2566	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
2567	struct dst_ops *dst_ops;
2568	struct xfrm_dst *xdst;
2569
2570	if (!afinfo)
2571		return ERR_PTR(-EINVAL);
2572
2573	switch (family) {
2574	case AF_INET:
2575		dst_ops = &net->xfrm.xfrm4_dst_ops;
2576		break;
2577#if IS_ENABLED(CONFIG_IPV6)
2578	case AF_INET6:
2579		dst_ops = &net->xfrm.xfrm6_dst_ops;
2580		break;
2581#endif
2582	default:
2583		BUG();
2584	}
2585	xdst = dst_alloc(dst_ops, NULL, DST_OBSOLETE_NONE, 0);
2586
2587	if (likely(xdst)) {
2588		memset_after(xdst, 0, u.dst);
 
 
2589	} else
2590		xdst = ERR_PTR(-ENOBUFS);
2591
2592	rcu_read_unlock();
2593
2594	return xdst;
2595}
2596
2597static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
2598			   int nfheader_len)
2599{
2600	if (dst->ops->family == AF_INET6) {
2601		path->path_cookie = rt6_get_cookie(dst_rt6_info(dst));
 
2602		path->u.rt6.rt6i_nfheader_len = nfheader_len;
2603	}
2604}
2605
2606static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
2607				const struct flowi *fl)
2608{
2609	const struct xfrm_policy_afinfo *afinfo =
2610		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
2611	int err;
2612
2613	if (!afinfo)
2614		return -EINVAL;
2615
2616	err = afinfo->fill_dst(xdst, dev, fl);
2617
2618	rcu_read_unlock();
2619
2620	return err;
2621}
2622
2623
2624/* Allocate chain of dst_entry's, attach known xfrm's, calculate
2625 * all the metrics... Shortly, bundle a bundle.
2626 */
2627
2628static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
2629					    struct xfrm_state **xfrm,
2630					    struct xfrm_dst **bundle,
2631					    int nx,
2632					    const struct flowi *fl,
2633					    struct dst_entry *dst)
2634{
2635	const struct xfrm_state_afinfo *afinfo;
2636	const struct xfrm_mode *inner_mode;
2637	struct net *net = xp_net(policy);
2638	unsigned long now = jiffies;
2639	struct net_device *dev;
2640	struct xfrm_dst *xdst_prev = NULL;
2641	struct xfrm_dst *xdst0 = NULL;
2642	int i = 0;
2643	int err;
2644	int header_len = 0;
2645	int nfheader_len = 0;
2646	int trailer_len = 0;
2647	int tos;
2648	int family = policy->selector.family;
2649	xfrm_address_t saddr, daddr;
2650
2651	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
2652
2653	tos = xfrm_get_tos(fl, family);
2654
2655	dst_hold(dst);
2656
2657	for (; i < nx; i++) {
2658		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
2659		struct dst_entry *dst1 = &xdst->u.dst;
2660
2661		err = PTR_ERR(xdst);
2662		if (IS_ERR(xdst)) {
2663			dst_release(dst);
2664			goto put_states;
2665		}
2666
2667		bundle[i] = xdst;
2668		if (!xdst_prev)
2669			xdst0 = xdst;
2670		else
2671			/* Ref count is taken during xfrm_alloc_dst()
2672			 * No need to do dst_clone() on dst1
2673			 */
2674			xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
2675
2676		if (xfrm[i]->sel.family == AF_UNSPEC) {
2677			inner_mode = xfrm_ip2inner_mode(xfrm[i],
2678							xfrm_af2proto(family));
2679			if (!inner_mode) {
2680				err = -EAFNOSUPPORT;
2681				dst_release(dst);
2682				goto put_states;
2683			}
2684		} else
2685			inner_mode = &xfrm[i]->inner_mode;
2686
2687		xdst->route = dst;
2688		dst_copy_metrics(dst1, dst);
2689
2690		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
2691			__u32 mark = 0;
2692			int oif;
2693
2694			if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
2695				mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
2696
2697			if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET)
2698				family = xfrm[i]->props.family;
2699
2700			oif = fl->flowi_oif ? : fl->flowi_l3mdev;
2701			dst = xfrm_dst_lookup(xfrm[i], tos, oif,
2702					      &saddr, &daddr, family, mark);
2703			err = PTR_ERR(dst);
2704			if (IS_ERR(dst))
2705				goto put_states;
2706		} else
2707			dst_hold(dst);
2708
2709		dst1->xfrm = xfrm[i];
2710		xdst->xfrm_genid = xfrm[i]->genid;
2711
2712		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
 
2713		dst1->lastuse = now;
2714
2715		dst1->input = dst_discard;
2716
2717		rcu_read_lock();
2718		afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
2719		if (likely(afinfo))
2720			dst1->output = afinfo->output;
2721		else
2722			dst1->output = dst_discard_out;
2723		rcu_read_unlock();
2724
2725		xdst_prev = xdst;
2726
2727		header_len += xfrm[i]->props.header_len;
2728		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
2729			nfheader_len += xfrm[i]->props.header_len;
2730		trailer_len += xfrm[i]->props.trailer_len;
2731	}
2732
2733	xfrm_dst_set_child(xdst_prev, dst);
2734	xdst0->path = dst;
2735
2736	err = -ENODEV;
2737	dev = dst->dev;
2738	if (!dev)
2739		goto free_dst;
2740
2741	xfrm_init_path(xdst0, dst, nfheader_len);
2742	xfrm_init_pmtu(bundle, nx);
2743
2744	for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
2745	     xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
2746		err = xfrm_fill_dst(xdst_prev, dev, fl);
2747		if (err)
2748			goto free_dst;
2749
2750		xdst_prev->u.dst.header_len = header_len;
2751		xdst_prev->u.dst.trailer_len = trailer_len;
2752		header_len -= xdst_prev->u.dst.xfrm->props.header_len;
2753		trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
2754	}
2755
2756	return &xdst0->u.dst;
2757
2758put_states:
2759	for (; i < nx; i++)
2760		xfrm_state_put(xfrm[i]);
2761free_dst:
2762	if (xdst0)
2763		dst_release_immediate(&xdst0->u.dst);
2764
2765	return ERR_PTR(err);
2766}
2767
2768static int xfrm_expand_policies(const struct flowi *fl, u16 family,
2769				struct xfrm_policy **pols,
2770				int *num_pols, int *num_xfrms)
2771{
2772	int i;
2773
2774	if (*num_pols == 0 || !pols[0]) {
2775		*num_pols = 0;
2776		*num_xfrms = 0;
2777		return 0;
2778	}
2779	if (IS_ERR(pols[0])) {
2780		*num_pols = 0;
2781		return PTR_ERR(pols[0]);
2782	}
2783
2784	*num_xfrms = pols[0]->xfrm_nr;
2785
2786#ifdef CONFIG_XFRM_SUB_POLICY
2787	if (pols[0]->action == XFRM_POLICY_ALLOW &&
2788	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
2789		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
2790						    XFRM_POLICY_TYPE_MAIN,
2791						    fl, family,
2792						    XFRM_POLICY_OUT,
2793						    pols[0]->if_id);
2794		if (pols[1]) {
2795			if (IS_ERR(pols[1])) {
2796				xfrm_pols_put(pols, *num_pols);
2797				*num_pols = 0;
2798				return PTR_ERR(pols[1]);
2799			}
2800			(*num_pols)++;
2801			(*num_xfrms) += pols[1]->xfrm_nr;
2802		}
2803	}
2804#endif
2805	for (i = 0; i < *num_pols; i++) {
2806		if (pols[i]->action != XFRM_POLICY_ALLOW) {
2807			*num_xfrms = -1;
2808			break;
2809		}
2810	}
2811
2812	return 0;
2813
2814}
2815
2816static struct xfrm_dst *
2817xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
2818			       const struct flowi *fl, u16 family,
2819			       struct dst_entry *dst_orig)
2820{
2821	struct net *net = xp_net(pols[0]);
2822	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
2823	struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
2824	struct xfrm_dst *xdst;
2825	struct dst_entry *dst;
2826	int err;
2827
2828	/* Try to instantiate a bundle */
2829	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
2830	if (err <= 0) {
2831		if (err == 0)
2832			return NULL;
2833
2834		if (err != -EAGAIN)
2835			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
2836		return ERR_PTR(err);
2837	}
2838
2839	dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
2840	if (IS_ERR(dst)) {
2841		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
2842		return ERR_CAST(dst);
2843	}
2844
2845	xdst = (struct xfrm_dst *)dst;
2846	xdst->num_xfrms = err;
2847	xdst->num_pols = num_pols;
2848	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
2849	xdst->policy_genid = atomic_read(&pols[0]->genid);
2850
2851	return xdst;
2852}
2853
2854static void xfrm_policy_queue_process(struct timer_list *t)
2855{
2856	struct sk_buff *skb;
2857	struct sock *sk;
2858	struct dst_entry *dst;
2859	struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
2860	struct net *net = xp_net(pol);
2861	struct xfrm_policy_queue *pq = &pol->polq;
2862	struct flowi fl;
2863	struct sk_buff_head list;
2864	__u32 skb_mark;
2865
2866	spin_lock(&pq->hold_queue.lock);
2867	skb = skb_peek(&pq->hold_queue);
2868	if (!skb) {
2869		spin_unlock(&pq->hold_queue.lock);
2870		goto out;
2871	}
2872	dst = skb_dst(skb);
2873	sk = skb->sk;
2874
2875	/* Fixup the mark to support VTI. */
2876	skb_mark = skb->mark;
2877	skb->mark = pol->mark.v;
2878	xfrm_decode_session(net, skb, &fl, dst->ops->family);
2879	skb->mark = skb_mark;
2880	spin_unlock(&pq->hold_queue.lock);
2881
2882	dst_hold(xfrm_dst_path(dst));
2883	dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
2884	if (IS_ERR(dst))
2885		goto purge_queue;
2886
2887	if (dst->flags & DST_XFRM_QUEUE) {
2888		dst_release(dst);
2889
2890		if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
2891			goto purge_queue;
2892
2893		pq->timeout = pq->timeout << 1;
2894		if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
2895			xfrm_pol_hold(pol);
2896		goto out;
2897	}
2898
2899	dst_release(dst);
2900
2901	__skb_queue_head_init(&list);
2902
2903	spin_lock(&pq->hold_queue.lock);
2904	pq->timeout = 0;
2905	skb_queue_splice_init(&pq->hold_queue, &list);
2906	spin_unlock(&pq->hold_queue.lock);
2907
2908	while (!skb_queue_empty(&list)) {
2909		skb = __skb_dequeue(&list);
2910
2911		/* Fixup the mark to support VTI. */
2912		skb_mark = skb->mark;
2913		skb->mark = pol->mark.v;
2914		xfrm_decode_session(net, skb, &fl, skb_dst(skb)->ops->family);
2915		skb->mark = skb_mark;
2916
2917		dst_hold(xfrm_dst_path(skb_dst(skb)));
2918		dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
2919		if (IS_ERR(dst)) {
2920			kfree_skb(skb);
2921			continue;
2922		}
2923
2924		nf_reset_ct(skb);
2925		skb_dst_drop(skb);
2926		skb_dst_set(skb, dst);
2927
2928		dst_output(net, skb->sk, skb);
2929	}
2930
2931out:
2932	xfrm_pol_put(pol);
2933	return;
2934
2935purge_queue:
2936	pq->timeout = 0;
2937	skb_queue_purge(&pq->hold_queue);
2938	xfrm_pol_put(pol);
2939}
2940
2941static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
2942{
2943	unsigned long sched_next;
2944	struct dst_entry *dst = skb_dst(skb);
2945	struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
2946	struct xfrm_policy *pol = xdst->pols[0];
2947	struct xfrm_policy_queue *pq = &pol->polq;
2948
2949	if (unlikely(skb_fclone_busy(sk, skb))) {
2950		kfree_skb(skb);
2951		return 0;
2952	}
2953
2954	if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
2955		kfree_skb(skb);
2956		return -EAGAIN;
2957	}
2958
2959	skb_dst_force(skb);
2960
2961	spin_lock_bh(&pq->hold_queue.lock);
2962
2963	if (!pq->timeout)
2964		pq->timeout = XFRM_QUEUE_TMO_MIN;
2965
2966	sched_next = jiffies + pq->timeout;
2967
2968	if (del_timer(&pq->hold_timer)) {
2969		if (time_before(pq->hold_timer.expires, sched_next))
2970			sched_next = pq->hold_timer.expires;
2971		xfrm_pol_put(pol);
2972	}
2973
2974	__skb_queue_tail(&pq->hold_queue, skb);
2975	if (!mod_timer(&pq->hold_timer, sched_next))
2976		xfrm_pol_hold(pol);
2977
2978	spin_unlock_bh(&pq->hold_queue.lock);
2979
2980	return 0;
2981}
2982
2983static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
2984						 struct xfrm_flo *xflo,
2985						 const struct flowi *fl,
2986						 int num_xfrms,
2987						 u16 family)
2988{
2989	int err;
2990	struct net_device *dev;
2991	struct dst_entry *dst;
2992	struct dst_entry *dst1;
2993	struct xfrm_dst *xdst;
2994
2995	xdst = xfrm_alloc_dst(net, family);
2996	if (IS_ERR(xdst))
2997		return xdst;
2998
2999	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
3000	    net->xfrm.sysctl_larval_drop ||
3001	    num_xfrms <= 0)
3002		return xdst;
3003
3004	dst = xflo->dst_orig;
3005	dst1 = &xdst->u.dst;
3006	dst_hold(dst);
3007	xdst->route = dst;
3008
3009	dst_copy_metrics(dst1, dst);
3010
3011	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
3012	dst1->flags |= DST_XFRM_QUEUE;
3013	dst1->lastuse = jiffies;
3014
3015	dst1->input = dst_discard;
3016	dst1->output = xdst_queue_output;
3017
3018	dst_hold(dst);
3019	xfrm_dst_set_child(xdst, dst);
3020	xdst->path = dst;
3021
3022	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
3023
3024	err = -ENODEV;
3025	dev = dst->dev;
3026	if (!dev)
3027		goto free_dst;
3028
3029	err = xfrm_fill_dst(xdst, dev, fl);
3030	if (err)
3031		goto free_dst;
3032
3033out:
3034	return xdst;
3035
3036free_dst:
3037	dst_release(dst1);
3038	xdst = ERR_PTR(err);
3039	goto out;
3040}
3041
3042static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
3043					   const struct flowi *fl,
3044					   u16 family, u8 dir,
3045					   struct xfrm_flo *xflo, u32 if_id)
3046{
3047	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3048	int num_pols = 0, num_xfrms = 0, err;
3049	struct xfrm_dst *xdst;
3050
3051	/* Resolve policies to use if we couldn't get them from
3052	 * previous cache entry */
3053	num_pols = 1;
3054	pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
3055	err = xfrm_expand_policies(fl, family, pols,
3056					   &num_pols, &num_xfrms);
3057	if (err < 0)
3058		goto inc_error;
3059	if (num_pols == 0)
3060		return NULL;
3061	if (num_xfrms <= 0)
3062		goto make_dummy_bundle;
3063
3064	xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
3065					      xflo->dst_orig);
3066	if (IS_ERR(xdst)) {
3067		err = PTR_ERR(xdst);
3068		if (err == -EREMOTE) {
3069			xfrm_pols_put(pols, num_pols);
3070			return NULL;
3071		}
3072
3073		if (err != -EAGAIN)
3074			goto error;
3075		goto make_dummy_bundle;
3076	} else if (xdst == NULL) {
3077		num_xfrms = 0;
3078		goto make_dummy_bundle;
3079	}
3080
3081	return xdst;
3082
3083make_dummy_bundle:
3084	/* We found policies, but there's no bundles to instantiate:
3085	 * either because the policy blocks, has no transformations or
3086	 * we could not build template (no xfrm_states).*/
3087	xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
3088	if (IS_ERR(xdst)) {
3089		xfrm_pols_put(pols, num_pols);
3090		return ERR_CAST(xdst);
3091	}
3092	xdst->num_pols = num_pols;
3093	xdst->num_xfrms = num_xfrms;
3094	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
3095
3096	return xdst;
3097
3098inc_error:
3099	XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
3100error:
3101	xfrm_pols_put(pols, num_pols);
3102	return ERR_PTR(err);
3103}
3104
3105static struct dst_entry *make_blackhole(struct net *net, u16 family,
3106					struct dst_entry *dst_orig)
3107{
3108	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
3109	struct dst_entry *ret;
3110
3111	if (!afinfo) {
3112		dst_release(dst_orig);
3113		return ERR_PTR(-EINVAL);
3114	} else {
3115		ret = afinfo->blackhole_route(net, dst_orig);
3116	}
3117	rcu_read_unlock();
3118
3119	return ret;
3120}
3121
3122/* Finds/creates a bundle for given flow and if_id
3123 *
3124 * At the moment we eat a raw IP route. Mostly to speed up lookups
3125 * on interfaces with disabled IPsec.
3126 *
3127 * xfrm_lookup uses an if_id of 0 by default, and is provided for
3128 * compatibility
3129 */
3130struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
3131					struct dst_entry *dst_orig,
3132					const struct flowi *fl,
3133					const struct sock *sk,
3134					int flags, u32 if_id)
3135{
3136	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3137	struct xfrm_dst *xdst;
3138	struct dst_entry *dst, *route;
3139	u16 family = dst_orig->ops->family;
3140	u8 dir = XFRM_POLICY_OUT;
3141	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
3142
3143	dst = NULL;
3144	xdst = NULL;
3145	route = NULL;
3146
3147	sk = sk_const_to_full_sk(sk);
3148	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
3149		num_pols = 1;
3150		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
3151						if_id);
3152		err = xfrm_expand_policies(fl, family, pols,
3153					   &num_pols, &num_xfrms);
3154		if (err < 0)
3155			goto dropdst;
3156
3157		if (num_pols) {
3158			if (num_xfrms <= 0) {
3159				drop_pols = num_pols;
3160				goto no_transform;
3161			}
3162
3163			xdst = xfrm_resolve_and_create_bundle(
3164					pols, num_pols, fl,
3165					family, dst_orig);
3166
3167			if (IS_ERR(xdst)) {
3168				xfrm_pols_put(pols, num_pols);
3169				err = PTR_ERR(xdst);
3170				if (err == -EREMOTE)
3171					goto nopol;
3172
3173				goto dropdst;
3174			} else if (xdst == NULL) {
3175				num_xfrms = 0;
3176				drop_pols = num_pols;
3177				goto no_transform;
3178			}
3179
3180			route = xdst->route;
3181		}
3182	}
3183
3184	if (xdst == NULL) {
3185		struct xfrm_flo xflo;
3186
3187		xflo.dst_orig = dst_orig;
3188		xflo.flags = flags;
3189
3190		/* To accelerate a bit...  */
3191		if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
3192			       !net->xfrm.policy_count[XFRM_POLICY_OUT]))
3193			goto nopol;
3194
3195		xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
3196		if (xdst == NULL)
3197			goto nopol;
3198		if (IS_ERR(xdst)) {
3199			err = PTR_ERR(xdst);
3200			goto dropdst;
3201		}
3202
3203		num_pols = xdst->num_pols;
3204		num_xfrms = xdst->num_xfrms;
3205		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
3206		route = xdst->route;
3207	}
3208
3209	dst = &xdst->u.dst;
3210	if (route == NULL && num_xfrms > 0) {
3211		/* The only case when xfrm_bundle_lookup() returns a
3212		 * bundle with null route, is when the template could
3213		 * not be resolved. It means policies are there, but
3214		 * bundle could not be created, since we don't yet
3215		 * have the xfrm_state's. We need to wait for KM to
3216		 * negotiate new SA's or bail out with error.*/
3217		if (net->xfrm.sysctl_larval_drop) {
3218			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3219			err = -EREMOTE;
3220			goto error;
3221		}
3222
3223		err = -EAGAIN;
3224
3225		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
3226		goto error;
3227	}
3228
3229no_transform:
3230	if (num_pols == 0)
3231		goto nopol;
3232
3233	if ((flags & XFRM_LOOKUP_ICMP) &&
3234	    !(pols[0]->flags & XFRM_POLICY_ICMP)) {
3235		err = -ENOENT;
3236		goto error;
3237	}
3238
3239	for (i = 0; i < num_pols; i++)
3240		WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds());
3241
3242	if (num_xfrms < 0) {
3243		/* Prohibit the flow */
3244		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
3245		err = -EPERM;
3246		goto error;
3247	} else if (num_xfrms > 0) {
3248		/* Flow transformed */
3249		dst_release(dst_orig);
3250	} else {
3251		/* Flow passes untransformed */
3252		dst_release(dst);
3253		dst = dst_orig;
3254	}
3255ok:
3256	xfrm_pols_put(pols, drop_pols);
3257	if (dst && dst->xfrm &&
3258	    dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
3259		dst->flags |= DST_XFRM_TUNNEL;
3260	return dst;
3261
3262nopol:
3263	if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
3264	    net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3265		err = -EPERM;
3266		goto error;
3267	}
3268	if (!(flags & XFRM_LOOKUP_ICMP)) {
3269		dst = dst_orig;
3270		goto ok;
3271	}
3272	err = -ENOENT;
3273error:
3274	dst_release(dst);
3275dropdst:
3276	if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
3277		dst_release(dst_orig);
3278	xfrm_pols_put(pols, drop_pols);
3279	return ERR_PTR(err);
3280}
3281EXPORT_SYMBOL(xfrm_lookup_with_ifid);
3282
3283/* Main function: finds/creates a bundle for given flow.
3284 *
3285 * At the moment we eat a raw IP route. Mostly to speed up lookups
3286 * on interfaces with disabled IPsec.
3287 */
3288struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
3289			      const struct flowi *fl, const struct sock *sk,
3290			      int flags)
3291{
3292	return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
3293}
3294EXPORT_SYMBOL(xfrm_lookup);
3295
3296/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
3297 * Otherwise we may send out blackholed packets.
3298 */
3299struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
3300				    const struct flowi *fl,
3301				    const struct sock *sk, int flags)
3302{
3303	struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
3304					    flags | XFRM_LOOKUP_QUEUE |
3305					    XFRM_LOOKUP_KEEP_DST_REF);
3306
3307	if (PTR_ERR(dst) == -EREMOTE)
3308		return make_blackhole(net, dst_orig->ops->family, dst_orig);
3309
3310	if (IS_ERR(dst))
3311		dst_release(dst_orig);
3312
3313	return dst;
3314}
3315EXPORT_SYMBOL(xfrm_lookup_route);
3316
3317static inline int
3318xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
3319{
3320	struct sec_path *sp = skb_sec_path(skb);
3321	struct xfrm_state *x;
3322
3323	if (!sp || idx < 0 || idx >= sp->len)
3324		return 0;
3325	x = sp->xvec[idx];
3326	if (!x->type->reject)
3327		return 0;
3328	return x->type->reject(x, skb, fl);
3329}
3330
3331/* When skb is transformed back to its "native" form, we have to
3332 * check policy restrictions. At the moment we make this in maximally
3333 * stupid way. Shame on me. :-) Of course, connected sockets must
3334 * have policy cached at them.
3335 */
3336
3337static inline int
3338xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
3339	      unsigned short family, u32 if_id)
3340{
3341	if (xfrm_state_kern(x))
3342		return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
3343	return	x->id.proto == tmpl->id.proto &&
3344		(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
3345		(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
3346		x->props.mode == tmpl->mode &&
3347		(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
3348		 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
3349		!(x->props.mode != XFRM_MODE_TRANSPORT &&
3350		  xfrm_state_addr_cmp(tmpl, x, family)) &&
3351		(if_id == 0 || if_id == x->if_id);
3352}
3353
3354/*
3355 * 0 or more than 0 is returned when validation is succeeded (either bypass
3356 * because of optional transport mode, or next index of the matched secpath
3357 * state with the template.
3358 * -1 is returned when no matching template is found.
3359 * Otherwise "-2 - errored_index" is returned.
3360 */
3361static inline int
3362xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
3363	       unsigned short family, u32 if_id)
3364{
3365	int idx = start;
3366
3367	if (tmpl->optional) {
3368		if (tmpl->mode == XFRM_MODE_TRANSPORT)
3369			return start;
3370	} else
3371		start = -1;
3372	for (; idx < sp->len; idx++) {
3373		if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
3374			return ++idx;
3375		if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
3376			if (idx < sp->verified_cnt) {
3377				/* Secpath entry previously verified, consider optional and
3378				 * continue searching
3379				 */
3380				continue;
3381			}
3382
3383			if (start == -1)
3384				start = -2-idx;
3385			break;
3386		}
3387	}
3388	return start;
3389}
3390
3391static void
3392decode_session4(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
3393{
 
 
 
3394	struct flowi4 *fl4 = &fl->u.ip4;
 
 
 
 
3395
3396	memset(fl4, 0, sizeof(struct flowi4));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3397
3398	if (reverse) {
3399		fl4->saddr = flkeys->addrs.ipv4.dst;
3400		fl4->daddr = flkeys->addrs.ipv4.src;
3401		fl4->fl4_sport = flkeys->ports.dst;
3402		fl4->fl4_dport = flkeys->ports.src;
3403	} else {
3404		fl4->saddr = flkeys->addrs.ipv4.src;
3405		fl4->daddr = flkeys->addrs.ipv4.dst;
3406		fl4->fl4_sport = flkeys->ports.src;
3407		fl4->fl4_dport = flkeys->ports.dst;
3408	}
3409
3410	switch (flkeys->basic.ip_proto) {
3411	case IPPROTO_GRE:
3412		fl4->fl4_gre_key = flkeys->gre.keyid;
3413		break;
3414	case IPPROTO_ICMP:
3415		fl4->fl4_icmp_type = flkeys->icmp.type;
3416		fl4->fl4_icmp_code = flkeys->icmp.code;
3417		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3418	}
3419
3420	fl4->flowi4_proto = flkeys->basic.ip_proto;
3421	fl4->flowi4_tos = flkeys->ip.tos & ~INET_ECN_MASK;
3422}
3423
3424#if IS_ENABLED(CONFIG_IPV6)
3425static void
3426decode_session6(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
3427{
3428	struct flowi6 *fl6 = &fl->u.ip6;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3429
3430	memset(fl6, 0, sizeof(struct flowi6));
 
 
3431
3432	if (reverse) {
3433		fl6->saddr = flkeys->addrs.ipv6.dst;
3434		fl6->daddr = flkeys->addrs.ipv6.src;
3435		fl6->fl6_sport = flkeys->ports.dst;
3436		fl6->fl6_dport = flkeys->ports.src;
3437	} else {
3438		fl6->saddr = flkeys->addrs.ipv6.src;
3439		fl6->daddr = flkeys->addrs.ipv6.dst;
3440		fl6->fl6_sport = flkeys->ports.src;
3441		fl6->fl6_dport = flkeys->ports.dst;
3442	}
3443
3444	switch (flkeys->basic.ip_proto) {
3445	case IPPROTO_GRE:
3446		fl6->fl6_gre_key = flkeys->gre.keyid;
3447		break;
3448	case IPPROTO_ICMPV6:
3449		fl6->fl6_icmp_type = flkeys->icmp.type;
3450		fl6->fl6_icmp_code = flkeys->icmp.code;
3451		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3452	}
3453
3454	fl6->flowi6_proto = flkeys->basic.ip_proto;
3455}
3456#endif
3457
3458int __xfrm_decode_session(struct net *net, struct sk_buff *skb, struct flowi *fl,
3459			  unsigned int family, int reverse)
3460{
3461	struct xfrm_flow_keys flkeys;
3462
3463	memset(&flkeys, 0, sizeof(flkeys));
3464	__skb_flow_dissect(net, skb, &xfrm_session_dissector, &flkeys,
3465			   NULL, 0, 0, 0, FLOW_DISSECTOR_F_STOP_AT_ENCAP);
3466
3467	switch (family) {
3468	case AF_INET:
3469		decode_session4(&flkeys, fl, reverse);
3470		break;
3471#if IS_ENABLED(CONFIG_IPV6)
3472	case AF_INET6:
3473		decode_session6(&flkeys, fl, reverse);
3474		break;
3475#endif
3476	default:
3477		return -EAFNOSUPPORT;
3478	}
3479
3480	fl->flowi_mark = skb->mark;
3481	if (reverse) {
3482		fl->flowi_oif = skb->skb_iif;
3483	} else {
3484		int oif = 0;
3485
3486		if (skb_dst(skb) && skb_dst(skb)->dev)
3487			oif = skb_dst(skb)->dev->ifindex;
3488
3489		fl->flowi_oif = oif;
3490	}
3491
3492	return security_xfrm_decode_session(skb, &fl->flowi_secid);
3493}
3494EXPORT_SYMBOL(__xfrm_decode_session);
3495
3496static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
3497{
3498	for (; k < sp->len; k++) {
3499		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
3500			*idxp = k;
3501			return 1;
3502		}
3503	}
3504
3505	return 0;
3506}
3507
3508static bool icmp_err_packet(const struct flowi *fl, unsigned short family)
3509{
3510	const struct flowi4 *fl4 = &fl->u.ip4;
3511
3512	if (family == AF_INET &&
3513	    fl4->flowi4_proto == IPPROTO_ICMP &&
3514	    (fl4->fl4_icmp_type == ICMP_DEST_UNREACH ||
3515	     fl4->fl4_icmp_type == ICMP_TIME_EXCEEDED))
3516		return true;
3517
3518#if IS_ENABLED(CONFIG_IPV6)
3519	if (family == AF_INET6) {
3520		const struct flowi6 *fl6 = &fl->u.ip6;
3521
3522		if (fl6->flowi6_proto == IPPROTO_ICMPV6 &&
3523		    (fl6->fl6_icmp_type == ICMPV6_DEST_UNREACH ||
3524		    fl6->fl6_icmp_type == ICMPV6_PKT_TOOBIG ||
3525		    fl6->fl6_icmp_type == ICMPV6_TIME_EXCEED))
3526			return true;
3527	}
3528#endif
3529	return false;
3530}
3531
3532static bool xfrm_icmp_flow_decode(struct sk_buff *skb, unsigned short family,
3533				  const struct flowi *fl, struct flowi *fl1)
3534{
3535	bool ret = true;
3536	struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
3537	int hl = family == AF_INET ? (sizeof(struct iphdr) +  sizeof(struct icmphdr)) :
3538		 (sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr));
3539
3540	if (!newskb)
3541		return true;
3542
3543	if (!pskb_pull(newskb, hl))
3544		goto out;
3545
3546	skb_reset_network_header(newskb);
3547
3548	if (xfrm_decode_session_reverse(dev_net(skb->dev), newskb, fl1, family) < 0)
3549		goto out;
3550
3551	fl1->flowi_oif = fl->flowi_oif;
3552	fl1->flowi_mark = fl->flowi_mark;
3553	fl1->flowi_tos = fl->flowi_tos;
3554	nf_nat_decode_session(newskb, fl1, family);
3555	ret = false;
3556
3557out:
3558	consume_skb(newskb);
3559	return ret;
3560}
3561
3562static bool xfrm_selector_inner_icmp_match(struct sk_buff *skb, unsigned short family,
3563					   const struct xfrm_selector *sel,
3564					   const struct flowi *fl)
3565{
3566	bool ret = false;
3567
3568	if (icmp_err_packet(fl, family)) {
3569		struct flowi fl1;
3570
3571		if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3572			return ret;
3573
3574		ret = xfrm_selector_match(sel, &fl1, family);
3575	}
3576
3577	return ret;
3578}
3579
3580static inline struct
3581xfrm_policy *xfrm_in_fwd_icmp(struct sk_buff *skb,
3582			      const struct flowi *fl, unsigned short family,
3583			      u32 if_id)
3584{
3585	struct xfrm_policy *pol = NULL;
3586
3587	if (icmp_err_packet(fl, family)) {
3588		struct flowi fl1;
3589		struct net *net = dev_net(skb->dev);
3590
3591		if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3592			return pol;
3593
3594		pol = xfrm_policy_lookup(net, &fl1, family, XFRM_POLICY_FWD, if_id);
3595		if (IS_ERR(pol))
3596			pol = NULL;
3597	}
3598
3599	return pol;
3600}
3601
3602static inline struct
3603dst_entry *xfrm_out_fwd_icmp(struct sk_buff *skb, struct flowi *fl,
3604			     unsigned short family, struct dst_entry *dst)
3605{
3606	if (icmp_err_packet(fl, family)) {
3607		struct net *net = dev_net(skb->dev);
3608		struct dst_entry *dst2;
3609		struct flowi fl1;
3610
3611		if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
3612			return dst;
3613
3614		dst_hold(dst);
3615
3616		dst2 = xfrm_lookup(net, dst, &fl1, NULL, (XFRM_LOOKUP_QUEUE | XFRM_LOOKUP_ICMP));
3617
3618		if (IS_ERR(dst2))
3619			return dst;
3620
3621		if (dst2->xfrm) {
3622			dst_release(dst);
3623			dst = dst2;
3624		} else {
3625			dst_release(dst2);
3626		}
3627	}
3628
3629	return dst;
3630}
3631
3632int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
3633			unsigned short family)
3634{
3635	struct net *net = dev_net(skb->dev);
3636	struct xfrm_policy *pol;
3637	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
3638	int npols = 0;
3639	int xfrm_nr;
3640	int pi;
3641	int reverse;
3642	struct flowi fl;
3643	int xerr_idx = -1;
3644	const struct xfrm_if_cb *ifcb;
3645	struct sec_path *sp;
 
3646	u32 if_id = 0;
3647
3648	rcu_read_lock();
3649	ifcb = xfrm_if_get_cb();
3650
3651	if (ifcb) {
3652		struct xfrm_if_decode_session_result r;
3653
3654		if (ifcb->decode_session(skb, family, &r)) {
3655			if_id = r.if_id;
3656			net = r.net;
3657		}
3658	}
3659	rcu_read_unlock();
3660
3661	reverse = dir & ~XFRM_POLICY_MASK;
3662	dir &= XFRM_POLICY_MASK;
3663
3664	if (__xfrm_decode_session(net, skb, &fl, family, reverse) < 0) {
3665		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
3666		return 0;
3667	}
3668
3669	nf_nat_decode_session(skb, &fl, family);
3670
3671	/* First, check used SA against their selectors. */
3672	sp = skb_sec_path(skb);
3673	if (sp) {
3674		int i;
3675
3676		for (i = sp->len - 1; i >= 0; i--) {
3677			struct xfrm_state *x = sp->xvec[i];
3678			int ret = 0;
3679
3680			if (!xfrm_selector_match(&x->sel, &fl, family)) {
3681				ret = 1;
3682				if (x->props.flags & XFRM_STATE_ICMP &&
3683				    xfrm_selector_inner_icmp_match(skb, family, &x->sel, &fl))
3684					ret = 0;
3685				if (ret) {
3686					XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
3687					return 0;
3688				}
3689			}
3690		}
3691	}
3692
3693	pol = NULL;
3694	sk = sk_to_full_sk(sk);
3695	if (sk && sk->sk_policy[dir]) {
3696		pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
3697		if (IS_ERR(pol)) {
3698			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3699			return 0;
3700		}
3701	}
3702
3703	if (!pol)
3704		pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
3705
3706	if (IS_ERR(pol)) {
3707		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3708		return 0;
3709	}
3710
3711	if (!pol && dir == XFRM_POLICY_FWD)
3712		pol = xfrm_in_fwd_icmp(skb, &fl, family, if_id);
3713
3714	if (!pol) {
3715		if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
3716			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3717			return 0;
3718		}
3719
3720		if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
3721			xfrm_secpath_reject(xerr_idx, skb, &fl);
3722			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
3723			return 0;
3724		}
3725		return 1;
3726	}
3727
3728	/* This lockless write can happen from different cpus. */
3729	WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
3730
3731	pols[0] = pol;
3732	npols++;
3733#ifdef CONFIG_XFRM_SUB_POLICY
3734	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
3735		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
3736						    &fl, family,
3737						    XFRM_POLICY_IN, if_id);
3738		if (pols[1]) {
3739			if (IS_ERR(pols[1])) {
3740				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
3741				xfrm_pol_put(pols[0]);
3742				return 0;
3743			}
3744			/* This write can happen from different cpus. */
3745			WRITE_ONCE(pols[1]->curlft.use_time,
3746				   ktime_get_real_seconds());
3747			npols++;
3748		}
3749	}
3750#endif
3751
3752	if (pol->action == XFRM_POLICY_ALLOW) {
3753		static struct sec_path dummy;
3754		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
3755		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
3756		struct xfrm_tmpl **tpp = tp;
3757		int ti = 0;
3758		int i, k;
3759
3760		sp = skb_sec_path(skb);
3761		if (!sp)
3762			sp = &dummy;
3763
3764		for (pi = 0; pi < npols; pi++) {
3765			if (pols[pi] != pol &&
3766			    pols[pi]->action != XFRM_POLICY_ALLOW) {
3767				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3768				goto reject;
3769			}
3770			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
3771				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
3772				goto reject_error;
3773			}
3774			for (i = 0; i < pols[pi]->xfrm_nr; i++)
3775				tpp[ti++] = &pols[pi]->xfrm_vec[i];
3776		}
3777		xfrm_nr = ti;
3778
3779		if (npols > 1) {
3780			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
3781			tpp = stp;
3782		}
3783
3784		/* For each tunnel xfrm, find the first matching tmpl.
3785		 * For each tmpl before that, find corresponding xfrm.
3786		 * Order is _important_. Later we will implement
3787		 * some barriers, but at the moment barriers
3788		 * are implied between each two transformations.
3789		 * Upon success, marks secpath entries as having been
3790		 * verified to allow them to be skipped in future policy
3791		 * checks (e.g. nested tunnels).
3792		 */
3793		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
3794			k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
3795			if (k < 0) {
3796				if (k < -1)
3797					/* "-2 - errored_index" returned */
3798					xerr_idx = -(2+k);
3799				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3800				goto reject;
3801			}
3802		}
3803
3804		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
3805			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
3806			goto reject;
3807		}
3808
3809		xfrm_pols_put(pols, npols);
3810		sp->verified_cnt = k;
3811
3812		return 1;
3813	}
3814	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
3815
3816reject:
3817	xfrm_secpath_reject(xerr_idx, skb, &fl);
3818reject_error:
3819	xfrm_pols_put(pols, npols);
3820	return 0;
3821}
3822EXPORT_SYMBOL(__xfrm_policy_check);
3823
3824int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
3825{
3826	struct net *net = dev_net(skb->dev);
3827	struct flowi fl;
3828	struct dst_entry *dst;
3829	int res = 1;
3830
3831	if (xfrm_decode_session(net, skb, &fl, family) < 0) {
3832		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3833		return 0;
3834	}
3835
3836	skb_dst_force(skb);
3837	if (!skb_dst(skb)) {
3838		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
3839		return 0;
3840	}
3841
3842	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
3843	if (IS_ERR(dst)) {
3844		res = 0;
3845		dst = NULL;
3846	}
3847
3848	if (dst && !dst->xfrm)
3849		dst = xfrm_out_fwd_icmp(skb, &fl, family, dst);
3850
3851	skb_dst_set(skb, dst);
3852	return res;
3853}
3854EXPORT_SYMBOL(__xfrm_route_forward);
3855
3856/* Optimize later using cookies and generation ids. */
3857
3858static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
3859{
3860	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
3861	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
3862	 * get validated by dst_ops->check on every use.  We do this
3863	 * because when a normal route referenced by an XFRM dst is
3864	 * obsoleted we do not go looking around for all parent
3865	 * referencing XFRM dsts so that we can invalidate them.  It
3866	 * is just too much work.  Instead we make the checks here on
3867	 * every use.  For example:
3868	 *
3869	 *	XFRM dst A --> IPv4 dst X
3870	 *
3871	 * X is the "xdst->route" of A (X is also the "dst->path" of A
3872	 * in this example).  If X is marked obsolete, "A" will not
3873	 * notice.  That's what we are validating here via the
3874	 * stale_bundle() check.
3875	 *
3876	 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
3877	 * be marked on it.
3878	 * This will force stale_bundle() to fail on any xdst bundle with
3879	 * this dst linked in it.
3880	 */
3881	if (dst->obsolete < 0 && !stale_bundle(dst))
3882		return dst;
3883
3884	return NULL;
3885}
3886
3887static int stale_bundle(struct dst_entry *dst)
3888{
3889	return !xfrm_bundle_ok((struct xfrm_dst *)dst);
3890}
3891
3892void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
3893{
3894	while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
3895		dst->dev = blackhole_netdev;
3896		dev_hold(dst->dev);
3897		dev_put(dev);
3898	}
3899}
3900EXPORT_SYMBOL(xfrm_dst_ifdown);
3901
3902static void xfrm_link_failure(struct sk_buff *skb)
3903{
3904	/* Impossible. Such dst must be popped before reaches point of failure. */
3905}
3906
3907static void xfrm_negative_advice(struct sock *sk, struct dst_entry *dst)
3908{
3909	if (dst->obsolete)
3910		sk_dst_reset(sk);
 
 
 
 
 
3911}
3912
3913static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
3914{
3915	while (nr--) {
3916		struct xfrm_dst *xdst = bundle[nr];
3917		u32 pmtu, route_mtu_cached;
3918		struct dst_entry *dst;
3919
3920		dst = &xdst->u.dst;
3921		pmtu = dst_mtu(xfrm_dst_child(dst));
3922		xdst->child_mtu_cached = pmtu;
3923
3924		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
3925
3926		route_mtu_cached = dst_mtu(xdst->route);
3927		xdst->route_mtu_cached = route_mtu_cached;
3928
3929		if (pmtu > route_mtu_cached)
3930			pmtu = route_mtu_cached;
3931
3932		dst_metric_set(dst, RTAX_MTU, pmtu);
3933	}
3934}
3935
3936/* Check that the bundle accepts the flow and its components are
3937 * still valid.
3938 */
3939
3940static int xfrm_bundle_ok(struct xfrm_dst *first)
3941{
3942	struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
3943	struct dst_entry *dst = &first->u.dst;
3944	struct xfrm_dst *xdst;
3945	int start_from, nr;
3946	u32 mtu;
3947
3948	if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
3949	    (dst->dev && !netif_running(dst->dev)))
3950		return 0;
3951
3952	if (dst->flags & DST_XFRM_QUEUE)
3953		return 1;
3954
3955	start_from = nr = 0;
3956	do {
3957		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
3958
3959		if (dst->xfrm->km.state != XFRM_STATE_VALID)
3960			return 0;
3961		if (xdst->xfrm_genid != dst->xfrm->genid)
3962			return 0;
3963		if (xdst->num_pols > 0 &&
3964		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
3965			return 0;
3966
3967		bundle[nr++] = xdst;
3968
3969		mtu = dst_mtu(xfrm_dst_child(dst));
3970		if (xdst->child_mtu_cached != mtu) {
3971			start_from = nr;
3972			xdst->child_mtu_cached = mtu;
3973		}
3974
3975		if (!dst_check(xdst->route, xdst->route_cookie))
3976			return 0;
3977		mtu = dst_mtu(xdst->route);
3978		if (xdst->route_mtu_cached != mtu) {
3979			start_from = nr;
3980			xdst->route_mtu_cached = mtu;
3981		}
3982
3983		dst = xfrm_dst_child(dst);
3984	} while (dst->xfrm);
3985
3986	if (likely(!start_from))
3987		return 1;
3988
3989	xdst = bundle[start_from - 1];
3990	mtu = xdst->child_mtu_cached;
3991	while (start_from--) {
3992		dst = &xdst->u.dst;
3993
3994		mtu = xfrm_state_mtu(dst->xfrm, mtu);
3995		if (mtu > xdst->route_mtu_cached)
3996			mtu = xdst->route_mtu_cached;
3997		dst_metric_set(dst, RTAX_MTU, mtu);
3998		if (!start_from)
3999			break;
4000
4001		xdst = bundle[start_from - 1];
4002		xdst->child_mtu_cached = mtu;
4003	}
4004
4005	return 1;
4006}
4007
4008static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
4009{
4010	return dst_metric_advmss(xfrm_dst_path(dst));
4011}
4012
4013static unsigned int xfrm_mtu(const struct dst_entry *dst)
4014{
4015	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
4016
4017	return mtu ? : dst_mtu(xfrm_dst_path(dst));
4018}
4019
4020static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
4021					const void *daddr)
4022{
4023	while (dst->xfrm) {
4024		const struct xfrm_state *xfrm = dst->xfrm;
4025
4026		dst = xfrm_dst_child(dst);
4027
4028		if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
4029			continue;
4030		if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
4031			daddr = xfrm->coaddr;
4032		else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
4033			daddr = &xfrm->id.daddr;
4034	}
4035	return daddr;
4036}
4037
4038static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
4039					   struct sk_buff *skb,
4040					   const void *daddr)
4041{
4042	const struct dst_entry *path = xfrm_dst_path(dst);
4043
4044	if (!skb)
4045		daddr = xfrm_get_dst_nexthop(dst, daddr);
4046	return path->ops->neigh_lookup(path, skb, daddr);
4047}
4048
4049static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
4050{
4051	const struct dst_entry *path = xfrm_dst_path(dst);
4052
4053	daddr = xfrm_get_dst_nexthop(dst, daddr);
4054	path->ops->confirm_neigh(path, daddr);
4055}
4056
4057int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
4058{
4059	int err = 0;
4060
4061	if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
4062		return -EAFNOSUPPORT;
4063
4064	spin_lock(&xfrm_policy_afinfo_lock);
4065	if (unlikely(xfrm_policy_afinfo[family] != NULL))
4066		err = -EEXIST;
4067	else {
4068		struct dst_ops *dst_ops = afinfo->dst_ops;
4069		if (likely(dst_ops->kmem_cachep == NULL))
4070			dst_ops->kmem_cachep = xfrm_dst_cache;
4071		if (likely(dst_ops->check == NULL))
4072			dst_ops->check = xfrm_dst_check;
4073		if (likely(dst_ops->default_advmss == NULL))
4074			dst_ops->default_advmss = xfrm_default_advmss;
4075		if (likely(dst_ops->mtu == NULL))
4076			dst_ops->mtu = xfrm_mtu;
4077		if (likely(dst_ops->negative_advice == NULL))
4078			dst_ops->negative_advice = xfrm_negative_advice;
4079		if (likely(dst_ops->link_failure == NULL))
4080			dst_ops->link_failure = xfrm_link_failure;
4081		if (likely(dst_ops->neigh_lookup == NULL))
4082			dst_ops->neigh_lookup = xfrm_neigh_lookup;
4083		if (likely(!dst_ops->confirm_neigh))
4084			dst_ops->confirm_neigh = xfrm_confirm_neigh;
4085		rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
4086	}
4087	spin_unlock(&xfrm_policy_afinfo_lock);
4088
4089	return err;
4090}
4091EXPORT_SYMBOL(xfrm_policy_register_afinfo);
4092
4093void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
4094{
4095	struct dst_ops *dst_ops = afinfo->dst_ops;
4096	int i;
4097
4098	for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
4099		if (xfrm_policy_afinfo[i] != afinfo)
4100			continue;
4101		RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
4102		break;
4103	}
4104
4105	synchronize_rcu();
4106
4107	dst_ops->kmem_cachep = NULL;
4108	dst_ops->check = NULL;
4109	dst_ops->negative_advice = NULL;
4110	dst_ops->link_failure = NULL;
4111}
4112EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
4113
4114void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
4115{
4116	spin_lock(&xfrm_if_cb_lock);
4117	rcu_assign_pointer(xfrm_if_cb, ifcb);
4118	spin_unlock(&xfrm_if_cb_lock);
4119}
4120EXPORT_SYMBOL(xfrm_if_register_cb);
4121
4122void xfrm_if_unregister_cb(void)
4123{
4124	RCU_INIT_POINTER(xfrm_if_cb, NULL);
4125	synchronize_rcu();
4126}
4127EXPORT_SYMBOL(xfrm_if_unregister_cb);
4128
4129#ifdef CONFIG_XFRM_STATISTICS
4130static int __net_init xfrm_statistics_init(struct net *net)
4131{
4132	int rv;
4133	net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
4134	if (!net->mib.xfrm_statistics)
4135		return -ENOMEM;
4136	rv = xfrm_proc_init(net);
4137	if (rv < 0)
4138		free_percpu(net->mib.xfrm_statistics);
4139	return rv;
4140}
4141
4142static void xfrm_statistics_fini(struct net *net)
4143{
4144	xfrm_proc_fini(net);
4145	free_percpu(net->mib.xfrm_statistics);
4146}
4147#else
4148static int __net_init xfrm_statistics_init(struct net *net)
4149{
4150	return 0;
4151}
4152
4153static void xfrm_statistics_fini(struct net *net)
4154{
4155}
4156#endif
4157
4158static int __net_init xfrm_policy_init(struct net *net)
4159{
4160	unsigned int hmask, sz;
4161	int dir, err;
4162
4163	if (net_eq(net, &init_net)) {
4164		xfrm_dst_cache = KMEM_CACHE(xfrm_dst, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
 
 
 
4165		err = rhashtable_init(&xfrm_policy_inexact_table,
4166				      &xfrm_pol_inexact_params);
4167		BUG_ON(err);
4168	}
4169
4170	hmask = 8 - 1;
4171	sz = (hmask+1) * sizeof(struct hlist_head);
4172
4173	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
4174	if (!net->xfrm.policy_byidx)
4175		goto out_byidx;
4176	net->xfrm.policy_idx_hmask = hmask;
4177
4178	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4179		struct xfrm_policy_hash *htab;
4180
4181		net->xfrm.policy_count[dir] = 0;
4182		net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
4183		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
4184
4185		htab = &net->xfrm.policy_bydst[dir];
4186		htab->table = xfrm_hash_alloc(sz);
4187		if (!htab->table)
4188			goto out_bydst;
4189		htab->hmask = hmask;
4190		htab->dbits4 = 32;
4191		htab->sbits4 = 32;
4192		htab->dbits6 = 128;
4193		htab->sbits6 = 128;
4194	}
4195	net->xfrm.policy_hthresh.lbits4 = 32;
4196	net->xfrm.policy_hthresh.rbits4 = 32;
4197	net->xfrm.policy_hthresh.lbits6 = 128;
4198	net->xfrm.policy_hthresh.rbits6 = 128;
4199
4200	seqlock_init(&net->xfrm.policy_hthresh.lock);
4201
4202	INIT_LIST_HEAD(&net->xfrm.policy_all);
4203	INIT_LIST_HEAD(&net->xfrm.inexact_bins);
4204	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
4205	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
4206	return 0;
4207
4208out_bydst:
4209	for (dir--; dir >= 0; dir--) {
4210		struct xfrm_policy_hash *htab;
4211
4212		htab = &net->xfrm.policy_bydst[dir];
4213		xfrm_hash_free(htab->table, sz);
4214	}
4215	xfrm_hash_free(net->xfrm.policy_byidx, sz);
4216out_byidx:
4217	return -ENOMEM;
4218}
4219
4220static void xfrm_policy_fini(struct net *net)
4221{
4222	struct xfrm_pol_inexact_bin *b, *t;
4223	unsigned int sz;
4224	int dir;
4225
4226	flush_work(&net->xfrm.policy_hash_work);
4227#ifdef CONFIG_XFRM_SUB_POLICY
4228	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
4229#endif
4230	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
4231
4232	WARN_ON(!list_empty(&net->xfrm.policy_all));
4233
4234	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
4235		struct xfrm_policy_hash *htab;
4236
4237		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
4238
4239		htab = &net->xfrm.policy_bydst[dir];
4240		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
4241		WARN_ON(!hlist_empty(htab->table));
4242		xfrm_hash_free(htab->table, sz);
4243	}
4244
4245	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
4246	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
4247	xfrm_hash_free(net->xfrm.policy_byidx, sz);
4248
4249	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4250	list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
4251		__xfrm_policy_inexact_prune_bin(b, true);
4252	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4253}
4254
4255static int __net_init xfrm_net_init(struct net *net)
4256{
4257	int rv;
4258
4259	/* Initialize the per-net locks here */
4260	spin_lock_init(&net->xfrm.xfrm_state_lock);
4261	spin_lock_init(&net->xfrm.xfrm_policy_lock);
4262	seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
4263	mutex_init(&net->xfrm.xfrm_cfg_mutex);
4264	net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
4265	net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
4266	net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
4267
4268	rv = xfrm_statistics_init(net);
4269	if (rv < 0)
4270		goto out_statistics;
4271	rv = xfrm_state_init(net);
4272	if (rv < 0)
4273		goto out_state;
4274	rv = xfrm_policy_init(net);
4275	if (rv < 0)
4276		goto out_policy;
4277	rv = xfrm_sysctl_init(net);
4278	if (rv < 0)
4279		goto out_sysctl;
4280
4281	return 0;
4282
4283out_sysctl:
4284	xfrm_policy_fini(net);
4285out_policy:
4286	xfrm_state_fini(net);
4287out_state:
4288	xfrm_statistics_fini(net);
4289out_statistics:
4290	return rv;
4291}
4292
4293static void __net_exit xfrm_net_exit(struct net *net)
4294{
4295	xfrm_sysctl_fini(net);
4296	xfrm_policy_fini(net);
4297	xfrm_state_fini(net);
4298	xfrm_statistics_fini(net);
4299}
4300
4301static struct pernet_operations __net_initdata xfrm_net_ops = {
4302	.init = xfrm_net_init,
4303	.exit = xfrm_net_exit,
4304};
4305
4306static const struct flow_dissector_key xfrm_flow_dissector_keys[] = {
4307	{
4308		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
4309		.offset = offsetof(struct xfrm_flow_keys, control),
4310	},
4311	{
4312		.key_id = FLOW_DISSECTOR_KEY_BASIC,
4313		.offset = offsetof(struct xfrm_flow_keys, basic),
4314	},
4315	{
4316		.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
4317		.offset = offsetof(struct xfrm_flow_keys, addrs.ipv4),
4318	},
4319	{
4320		.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
4321		.offset = offsetof(struct xfrm_flow_keys, addrs.ipv6),
4322	},
4323	{
4324		.key_id = FLOW_DISSECTOR_KEY_PORTS,
4325		.offset = offsetof(struct xfrm_flow_keys, ports),
4326	},
4327	{
4328		.key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
4329		.offset = offsetof(struct xfrm_flow_keys, gre),
4330	},
4331	{
4332		.key_id = FLOW_DISSECTOR_KEY_IP,
4333		.offset = offsetof(struct xfrm_flow_keys, ip),
4334	},
4335	{
4336		.key_id = FLOW_DISSECTOR_KEY_ICMP,
4337		.offset = offsetof(struct xfrm_flow_keys, icmp),
4338	},
4339};
4340
4341void __init xfrm_init(void)
4342{
4343	skb_flow_dissector_init(&xfrm_session_dissector,
4344				xfrm_flow_dissector_keys,
4345				ARRAY_SIZE(xfrm_flow_dissector_keys));
4346
4347	register_pernet_subsys(&xfrm_net_ops);
4348	xfrm_dev_init();
 
4349	xfrm_input_init();
4350
4351#ifdef CONFIG_XFRM_ESPINTCP
4352	espintcp_init();
4353#endif
4354
4355	register_xfrm_state_bpf();
4356}
4357
4358#ifdef CONFIG_AUDITSYSCALL
4359static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
4360					 struct audit_buffer *audit_buf)
4361{
4362	struct xfrm_sec_ctx *ctx = xp->security;
4363	struct xfrm_selector *sel = &xp->selector;
4364
4365	if (ctx)
4366		audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
4367				 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
4368
4369	switch (sel->family) {
4370	case AF_INET:
4371		audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
4372		if (sel->prefixlen_s != 32)
4373			audit_log_format(audit_buf, " src_prefixlen=%d",
4374					 sel->prefixlen_s);
4375		audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
4376		if (sel->prefixlen_d != 32)
4377			audit_log_format(audit_buf, " dst_prefixlen=%d",
4378					 sel->prefixlen_d);
4379		break;
4380	case AF_INET6:
4381		audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
4382		if (sel->prefixlen_s != 128)
4383			audit_log_format(audit_buf, " src_prefixlen=%d",
4384					 sel->prefixlen_s);
4385		audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
4386		if (sel->prefixlen_d != 128)
4387			audit_log_format(audit_buf, " dst_prefixlen=%d",
4388					 sel->prefixlen_d);
4389		break;
4390	}
4391}
4392
4393void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
4394{
4395	struct audit_buffer *audit_buf;
4396
4397	audit_buf = xfrm_audit_start("SPD-add");
4398	if (audit_buf == NULL)
4399		return;
4400	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4401	audit_log_format(audit_buf, " res=%u", result);
4402	xfrm_audit_common_policyinfo(xp, audit_buf);
4403	audit_log_end(audit_buf);
4404}
4405EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
4406
4407void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
4408			      bool task_valid)
4409{
4410	struct audit_buffer *audit_buf;
4411
4412	audit_buf = xfrm_audit_start("SPD-delete");
4413	if (audit_buf == NULL)
4414		return;
4415	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
4416	audit_log_format(audit_buf, " res=%u", result);
4417	xfrm_audit_common_policyinfo(xp, audit_buf);
4418	audit_log_end(audit_buf);
4419}
4420EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
4421#endif
4422
4423#ifdef CONFIG_XFRM_MIGRATE
4424static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
4425					const struct xfrm_selector *sel_tgt)
4426{
4427	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
4428		if (sel_tgt->family == sel_cmp->family &&
4429		    xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
4430				    sel_cmp->family) &&
4431		    xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
4432				    sel_cmp->family) &&
4433		    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
4434		    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
4435			return true;
4436		}
4437	} else {
4438		if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
4439			return true;
4440		}
4441	}
4442	return false;
4443}
4444
4445static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
4446						    u8 dir, u8 type, struct net *net, u32 if_id)
4447{
4448	struct xfrm_policy *pol, *ret = NULL;
4449	struct hlist_head *chain;
4450	u32 priority = ~0U;
4451
4452	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
4453	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
4454	hlist_for_each_entry(pol, chain, bydst) {
4455		if ((if_id == 0 || pol->if_id == if_id) &&
4456		    xfrm_migrate_selector_match(sel, &pol->selector) &&
4457		    pol->type == type) {
4458			ret = pol;
4459			priority = ret->priority;
4460			break;
4461		}
4462	}
4463	chain = &net->xfrm.policy_inexact[dir];
4464	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
4465		if ((pol->priority >= priority) && ret)
4466			break;
4467
4468		if ((if_id == 0 || pol->if_id == if_id) &&
4469		    xfrm_migrate_selector_match(sel, &pol->selector) &&
4470		    pol->type == type) {
4471			ret = pol;
4472			break;
4473		}
4474	}
4475
4476	xfrm_pol_hold(ret);
4477
4478	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
4479
4480	return ret;
4481}
4482
4483static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
4484{
4485	int match = 0;
4486
4487	if (t->mode == m->mode && t->id.proto == m->proto &&
4488	    (m->reqid == 0 || t->reqid == m->reqid)) {
4489		switch (t->mode) {
4490		case XFRM_MODE_TUNNEL:
4491		case XFRM_MODE_BEET:
4492			if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
4493					    m->old_family) &&
4494			    xfrm_addr_equal(&t->saddr, &m->old_saddr,
4495					    m->old_family)) {
4496				match = 1;
4497			}
4498			break;
4499		case XFRM_MODE_TRANSPORT:
4500			/* in case of transport mode, template does not store
4501			   any IP addresses, hence we just compare mode and
4502			   protocol */
4503			match = 1;
4504			break;
4505		default:
4506			break;
4507		}
4508	}
4509	return match;
4510}
4511
4512/* update endpoint address(es) of template(s) */
4513static int xfrm_policy_migrate(struct xfrm_policy *pol,
4514			       struct xfrm_migrate *m, int num_migrate,
4515			       struct netlink_ext_ack *extack)
4516{
4517	struct xfrm_migrate *mp;
4518	int i, j, n = 0;
4519
4520	write_lock_bh(&pol->lock);
4521	if (unlikely(pol->walk.dead)) {
4522		/* target policy has been deleted */
4523		NL_SET_ERR_MSG(extack, "Target policy not found");
4524		write_unlock_bh(&pol->lock);
4525		return -ENOENT;
4526	}
4527
4528	for (i = 0; i < pol->xfrm_nr; i++) {
4529		for (j = 0, mp = m; j < num_migrate; j++, mp++) {
4530			if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
4531				continue;
4532			n++;
4533			if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
4534			    pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
4535				continue;
4536			/* update endpoints */
4537			memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
4538			       sizeof(pol->xfrm_vec[i].id.daddr));
4539			memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
4540			       sizeof(pol->xfrm_vec[i].saddr));
4541			pol->xfrm_vec[i].encap_family = mp->new_family;
4542			/* flush bundles */
4543			atomic_inc(&pol->genid);
4544		}
4545	}
4546
4547	write_unlock_bh(&pol->lock);
4548
4549	if (!n)
4550		return -ENODATA;
4551
4552	return 0;
4553}
4554
4555static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
4556			      struct netlink_ext_ack *extack)
4557{
4558	int i, j;
4559
4560	if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
4561		NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
4562		return -EINVAL;
4563	}
4564
4565	for (i = 0; i < num_migrate; i++) {
4566		if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
4567		    xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
4568			NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
4569			return -EINVAL;
4570		}
4571
4572		/* check if there is any duplicated entry */
4573		for (j = i + 1; j < num_migrate; j++) {
4574			if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
4575				    sizeof(m[i].old_daddr)) &&
4576			    !memcmp(&m[i].old_saddr, &m[j].old_saddr,
4577				    sizeof(m[i].old_saddr)) &&
4578			    m[i].proto == m[j].proto &&
4579			    m[i].mode == m[j].mode &&
4580			    m[i].reqid == m[j].reqid &&
4581			    m[i].old_family == m[j].old_family) {
4582				NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
4583				return -EINVAL;
4584			}
4585		}
4586	}
4587
4588	return 0;
4589}
4590
4591int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
4592		 struct xfrm_migrate *m, int num_migrate,
4593		 struct xfrm_kmaddress *k, struct net *net,
4594		 struct xfrm_encap_tmpl *encap, u32 if_id,
4595		 struct netlink_ext_ack *extack)
4596{
4597	int i, err, nx_cur = 0, nx_new = 0;
4598	struct xfrm_policy *pol = NULL;
4599	struct xfrm_state *x, *xc;
4600	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
4601	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
4602	struct xfrm_migrate *mp;
4603
4604	/* Stage 0 - sanity checks */
4605	err = xfrm_migrate_check(m, num_migrate, extack);
4606	if (err < 0)
4607		goto out;
4608
4609	if (dir >= XFRM_POLICY_MAX) {
4610		NL_SET_ERR_MSG(extack, "Invalid policy direction");
4611		err = -EINVAL;
4612		goto out;
4613	}
4614
4615	/* Stage 1 - find policy */
4616	pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
4617	if (!pol) {
4618		NL_SET_ERR_MSG(extack, "Target policy not found");
4619		err = -ENOENT;
4620		goto out;
4621	}
4622
4623	/* Stage 2 - find and update state(s) */
4624	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
4625		if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
4626			x_cur[nx_cur] = x;
4627			nx_cur++;
4628			xc = xfrm_state_migrate(x, mp, encap);
4629			if (xc) {
4630				x_new[nx_new] = xc;
4631				nx_new++;
4632			} else {
4633				err = -ENODATA;
4634				goto restore_state;
4635			}
4636		}
4637	}
4638
4639	/* Stage 3 - update policy */
4640	err = xfrm_policy_migrate(pol, m, num_migrate, extack);
4641	if (err < 0)
4642		goto restore_state;
4643
4644	/* Stage 4 - delete old state(s) */
4645	if (nx_cur) {
4646		xfrm_states_put(x_cur, nx_cur);
4647		xfrm_states_delete(x_cur, nx_cur);
4648	}
4649
4650	/* Stage 5 - announce */
4651	km_migrate(sel, dir, type, m, num_migrate, k, encap);
4652
4653	xfrm_pol_put(pol);
4654
4655	return 0;
4656out:
4657	return err;
4658
4659restore_state:
4660	if (pol)
4661		xfrm_pol_put(pol);
4662	if (nx_cur)
4663		xfrm_states_put(x_cur, nx_cur);
4664	if (nx_new)
4665		xfrm_states_delete(x_new, nx_new);
4666
4667	return err;
4668}
4669EXPORT_SYMBOL(xfrm_migrate);
4670#endif