Initial import

1 files changed, 3397 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
new file mode 100644
index 000000000..638af0655
--- /dev/null
+++ b/net/xfrm/xfrm_policy.c
@@ -0,0 +1,3397 @@
+/*
+ * xfrm_policy.c
+ *
+ * Changes:
+ *	Mitsuru KANDA @USAGI
+ * 	Kazunori MIYAZAWA @USAGI
+ * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
+ * 		IPv6 support
+ * 	Kazunori MIYAZAWA @USAGI
+ * 	YOSHIFUJI Hideaki
+ * 		Split up af-specific portion
+ *	Derek Atkins <derek@ihtfp.com>		Add the post_input processor
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/kmod.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/notifier.h>
+#include <linux/netdevice.h>
+#include <linux/netfilter.h>
+#include <linux/module.h>
+#include <linux/cache.h>
+#include <linux/audit.h>
+#include <net/dst.h>
+#include <net/flow.h>
+#include <net/xfrm.h>
+#include <net/ip.h>
+#ifdef CONFIG_XFRM_STATISTICS
+#include <net/snmp.h>
+#endif
+
+#include "xfrm_hash.h"
+
+#define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
+#define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
+#define XFRM_MAX_QUEUE_LEN	100
+
+struct xfrm_flo {
+	struct dst_entry *dst_orig;
+	u8 flags;
+};
+
+static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
+static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
+						__read_mostly;
+
+static struct kmem_cache *xfrm_dst_cache __read_mostly;
+
+static void xfrm_init_pmtu(struct dst_entry *dst);
+static int stale_bundle(struct dst_entry *dst);
+static int xfrm_bundle_ok(struct xfrm_dst *xdst);
+static void xfrm_policy_queue_process(unsigned long arg);
+
+static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
+static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
+						int dir);
+
+static inline bool
+__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
+{
+	const struct flowi4 *fl4 = &fl->u.ip4;
+
+	return  addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
+		addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
+		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
+		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
+		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
+		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
+}
+
+static inline bool
+__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
+{
+	const struct flowi6 *fl6 = &fl->u.ip6;
+
+	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
+		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
+		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
+		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
+		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
+		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
+}
+
+bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
+			 unsigned short family)
+{
+	switch (family) {
+	case AF_INET:
+		return __xfrm4_selector_match(sel, fl);
+	case AF_INET6:
+		return __xfrm6_selector_match(sel, fl);
+	}
+	return false;
+}
+
+static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
+{
+	struct xfrm_policy_afinfo *afinfo;
+
+	if (unlikely(family >= NPROTO))
+		return NULL;
+	rcu_read_lock();
+	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
+	if (unlikely(!afinfo))
+		rcu_read_unlock();
+	return afinfo;
+}
+
+static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
+{
+	rcu_read_unlock();
+}
+
+static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
+						  const xfrm_address_t *saddr,
+						  const xfrm_address_t *daddr,
+						  int family)
+{
+	struct xfrm_policy_afinfo *afinfo;
+	struct dst_entry *dst;
+
+	afinfo = xfrm_policy_get_afinfo(family);
+	if (unlikely(afinfo == NULL))
+		return ERR_PTR(-EAFNOSUPPORT);
+
+	dst = afinfo->dst_lookup(net, tos, saddr, daddr);
+
+	xfrm_policy_put_afinfo(afinfo);
+
+	return dst;
+}
+
+static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x, int tos,
+						xfrm_address_t *prev_saddr,
+						xfrm_address_t *prev_daddr,
+						int family)
+{
+	struct net *net = xs_net(x);
+	xfrm_address_t *saddr = &x->props.saddr;
+	xfrm_address_t *daddr = &x->id.daddr;
+	struct dst_entry *dst;
+
+	if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
+		saddr = x->coaddr;
+		daddr = prev_daddr;
+	}
+	if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
+		saddr = prev_saddr;
+		daddr = x->coaddr;
+	}
+
+	dst = __xfrm_dst_lookup(net, tos, saddr, daddr, family);
+
+	if (!IS_ERR(dst)) {
+		if (prev_saddr != saddr)
+			memcpy(prev_saddr, saddr,  sizeof(*prev_saddr));
+		if (prev_daddr != daddr)
+			memcpy(prev_daddr, daddr,  sizeof(*prev_daddr));
+	}
+
+	return dst;
+}
+
+static inline unsigned long make_jiffies(long secs)
+{
+	if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
+		return MAX_SCHEDULE_TIMEOUT-1;
+	else
+		return secs*HZ;
+}
+
+static void xfrm_policy_timer(unsigned long data)
+{
+	struct xfrm_policy *xp = (struct xfrm_policy *)data;
+	unsigned long now = get_seconds();
+	long next = LONG_MAX;
+	int warn = 0;
+	int dir;
+
+	read_lock(&xp->lock);
+
+	if (unlikely(xp->walk.dead))
+		goto out;
+
+	dir = xfrm_policy_id2dir(xp->index);
+
+	if (xp->lft.hard_add_expires_seconds) {
+		long tmo = xp->lft.hard_add_expires_seconds +
+			xp->curlft.add_time - now;
+		if (tmo <= 0)
+			goto expired;
+		if (tmo < next)
+			next = tmo;
+	}
+	if (xp->lft.hard_use_expires_seconds) {
+		long tmo = xp->lft.hard_use_expires_seconds +
+			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
+		if (tmo <= 0)
+			goto expired;
+		if (tmo < next)
+			next = tmo;
+	}
+	if (xp->lft.soft_add_expires_seconds) {
+		long tmo = xp->lft.soft_add_expires_seconds +
+			xp->curlft.add_time - now;
+		if (tmo <= 0) {
+			warn = 1;
+			tmo = XFRM_KM_TIMEOUT;
+		}
+		if (tmo < next)
+			next = tmo;
+	}
+	if (xp->lft.soft_use_expires_seconds) {
+		long tmo = xp->lft.soft_use_expires_seconds +
+			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
+		if (tmo <= 0) {
+			warn = 1;
+			tmo = XFRM_KM_TIMEOUT;
+		}
+		if (tmo < next)
+			next = tmo;
+	}
+
+	if (warn)
+		km_policy_expired(xp, dir, 0, 0);
+	if (next != LONG_MAX &&
+	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
+		xfrm_pol_hold(xp);
+
+out:
+	read_unlock(&xp->lock);
+	xfrm_pol_put(xp);
+	return;
+
+expired:
+	read_unlock(&xp->lock);
+	if (!xfrm_policy_delete(xp, dir))
+		km_policy_expired(xp, dir, 1, 0);
+	xfrm_pol_put(xp);
+}
+
+static struct flow_cache_object *xfrm_policy_flo_get(struct flow_cache_object *flo)
+{
+	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
+
+	if (unlikely(pol->walk.dead))
+		flo = NULL;
+	else
+		xfrm_pol_hold(pol);
+
+	return flo;
+}
+
+static int xfrm_policy_flo_check(struct flow_cache_object *flo)
+{
+	struct xfrm_policy *pol = container_of(flo, struct xfrm_policy, flo);
+
+	return !pol->walk.dead;
+}
+
+static void xfrm_policy_flo_delete(struct flow_cache_object *flo)
+{
+	xfrm_pol_put(container_of(flo, struct xfrm_policy, flo));
+}
+
+static const struct flow_cache_ops xfrm_policy_fc_ops = {
+	.get = xfrm_policy_flo_get,
+	.check = xfrm_policy_flo_check,
+	.delete = xfrm_policy_flo_delete,
+};
+
+/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
+ * SPD calls.
+ */
+
+struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
+{
+	struct xfrm_policy *policy;
+
+	policy = kzalloc(sizeof(struct xfrm_policy), gfp);
+
+	if (policy) {
+		write_pnet(&policy->xp_net, net);
+		INIT_LIST_HEAD(&policy->walk.all);
+		INIT_HLIST_NODE(&policy->bydst);
+		INIT_HLIST_NODE(&policy->byidx);
+		rwlock_init(&policy->lock);
+		atomic_set(&policy->refcnt, 1);
+		skb_queue_head_init(&policy->polq.hold_queue);
+		setup_timer(&policy->timer, xfrm_policy_timer,
+				(unsigned long)policy);
+		setup_timer(&policy->polq.hold_timer, xfrm_policy_queue_process,
+			    (unsigned long)policy);
+		policy->flo.ops = &xfrm_policy_fc_ops;
+	}
+	return policy;
+}
+EXPORT_SYMBOL(xfrm_policy_alloc);
+
+/* Destroy xfrm_policy: descendant resources must be released to this moment. */
+
+void xfrm_policy_destroy(struct xfrm_policy *policy)
+{
+	BUG_ON(!policy->walk.dead);
+
+	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
+		BUG();
+
+	security_xfrm_policy_free(policy->security);
+	kfree(policy);
+}
+EXPORT_SYMBOL(xfrm_policy_destroy);
+
+static void xfrm_queue_purge(struct sk_buff_head *list)
+{
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue(list)) != NULL)
+		kfree_skb(skb);
+}
+
+/* Rule must be locked. Release descentant resources, announce
+ * entry dead. The rule must be unlinked from lists to the moment.
+ */
+
+static void xfrm_policy_kill(struct xfrm_policy *policy)
+{
+	policy->walk.dead = 1;
+
+	atomic_inc(&policy->genid);
+
+	if (del_timer(&policy->polq.hold_timer))
+		xfrm_pol_put(policy);
+	xfrm_queue_purge(&policy->polq.hold_queue);
+
+	if (del_timer(&policy->timer))
+		xfrm_pol_put(policy);
+
+	xfrm_pol_put(policy);
+}
+
+static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
+
+static inline unsigned int idx_hash(struct net *net, u32 index)
+{
+	return __idx_hash(index, net->xfrm.policy_idx_hmask);
+}
+
+/* calculate policy hash thresholds */
+static void __get_hash_thresh(struct net *net,
+			      unsigned short family, int dir,
+			      u8 *dbits, u8 *sbits)
+{
+	switch (family) {
+	case AF_INET:
+		*dbits = net->xfrm.policy_bydst[dir].dbits4;
+		*sbits = net->xfrm.policy_bydst[dir].sbits4;
+		break;
+
+	case AF_INET6:
+		*dbits = net->xfrm.policy_bydst[dir].dbits6;
+		*sbits = net->xfrm.policy_bydst[dir].sbits6;
+		break;
+
+	default:
+		*dbits = 0;
+		*sbits = 0;
+	}
+}
+
+static struct hlist_head *policy_hash_bysel(struct net *net,
+					    const struct xfrm_selector *sel,
+					    unsigned short family, int dir)
+{
+	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
+	unsigned int hash;
+	u8 dbits;
+	u8 sbits;
+
+	__get_hash_thresh(net, family, dir, &dbits, &sbits);
+	hash = __sel_hash(sel, family, hmask, dbits, sbits);
+
+	return (hash == hmask + 1 ?
+		&net->xfrm.policy_inexact[dir] :
+		net->xfrm.policy_bydst[dir].table + hash);
+}
+
+static struct hlist_head *policy_hash_direct(struct net *net,
+					     const xfrm_address_t *daddr,
+					     const xfrm_address_t *saddr,
+					     unsigned short family, int dir)
+{
+	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
+	unsigned int hash;
+	u8 dbits;
+	u8 sbits;
+
+	__get_hash_thresh(net, family, dir, &dbits, &sbits);
+	hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
+
+	return net->xfrm.policy_bydst[dir].table + hash;
+}
+
+static void xfrm_dst_hash_transfer(struct net *net,
+				   struct hlist_head *list,
+				   struct hlist_head *ndsttable,
+				   unsigned int nhashmask,
+				   int dir)
+{
+	struct hlist_node *tmp, *entry0 = NULL;
+	struct xfrm_policy *pol;
+	unsigned int h0 = 0;
+	u8 dbits;
+	u8 sbits;
+
+redo:
+	hlist_for_each_entry_safe(pol, tmp, list, bydst) {
+		unsigned int h;
+
+		__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
+		h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
+				pol->family, nhashmask, dbits, sbits);
+		if (!entry0) {
+			hlist_del(&pol->bydst);
+			hlist_add_head(&pol->bydst, ndsttable+h);
+			h0 = h;
+		} else {
+			if (h != h0)
+				continue;
+			hlist_del(&pol->bydst);
+			hlist_add_behind(&pol->bydst, entry0);
+		}
+		entry0 = &pol->bydst;
+	}
+	if (!hlist_empty(list)) {
+		entry0 = NULL;
+		goto redo;
+	}
+}
+
+static void xfrm_idx_hash_transfer(struct hlist_head *list,
+				   struct hlist_head *nidxtable,
+				   unsigned int nhashmask)
+{
+	struct hlist_node *tmp;
+	struct xfrm_policy *pol;
+
+	hlist_for_each_entry_safe(pol, tmp, list, byidx) {
+		unsigned int h;
+
+		h = __idx_hash(pol->index, nhashmask);
+		hlist_add_head(&pol->byidx, nidxtable+h);
+	}
+}
+
+static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
+{
+	return ((old_hmask + 1) << 1) - 1;
+}
+
+static void xfrm_bydst_resize(struct net *net, int dir)
+{
+	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
+	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
+	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
+	struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
+	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
+	int i;
+
+	if (!ndst)
+		return;
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+
+	for (i = hmask; i >= 0; i--)
+		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
+
+	net->xfrm.policy_bydst[dir].table = ndst;
+	net->xfrm.policy_bydst[dir].hmask = nhashmask;
+
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
+}
+
+static void xfrm_byidx_resize(struct net *net, int total)
+{
+	unsigned int hmask = net->xfrm.policy_idx_hmask;
+	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
+	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
+	struct hlist_head *oidx = net->xfrm.policy_byidx;
+	struct hlist_head *nidx = xfrm_hash_alloc(nsize);
+	int i;
+
+	if (!nidx)
+		return;
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+
+	for (i = hmask; i >= 0; i--)
+		xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
+
+	net->xfrm.policy_byidx = nidx;
+	net->xfrm.policy_idx_hmask = nhashmask;
+
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
+}
+
+static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
+{
+	unsigned int cnt = net->xfrm.policy_count[dir];
+	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
+
+	if (total)
+		*total += cnt;
+
+	if ((hmask + 1) < xfrm_policy_hashmax &&
+	    cnt > hmask)
+		return 1;
+
+	return 0;
+}
+
+static inline int xfrm_byidx_should_resize(struct net *net, int total)
+{
+	unsigned int hmask = net->xfrm.policy_idx_hmask;
+
+	if ((hmask + 1) < xfrm_policy_hashmax &&
+	    total > hmask)
+		return 1;
+
+	return 0;
+}
+
+void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
+{
+	read_lock_bh(&net->xfrm.xfrm_policy_lock);
+	si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
+	si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
+	si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
+	si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
+	si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
+	si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
+	si->spdhcnt = net->xfrm.policy_idx_hmask;
+	si->spdhmcnt = xfrm_policy_hashmax;
+	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+}
+EXPORT_SYMBOL(xfrm_spd_getinfo);
+
+static DEFINE_MUTEX(hash_resize_mutex);
+static void xfrm_hash_resize(struct work_struct *work)
+{
+	struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
+	int dir, total;
+
+	mutex_lock(&hash_resize_mutex);
+
+	total = 0;
+	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
+		if (xfrm_bydst_should_resize(net, dir, &total))
+			xfrm_bydst_resize(net, dir);
+	}
+	if (xfrm_byidx_should_resize(net, total))
+		xfrm_byidx_resize(net, total);
+
+	mutex_unlock(&hash_resize_mutex);
+}
+
+static void xfrm_hash_rebuild(struct work_struct *work)
+{
+	struct net *net = container_of(work, struct net,
+				       xfrm.policy_hthresh.work);
+	unsigned int hmask;
+	struct xfrm_policy *pol;
+	struct xfrm_policy *policy;
+	struct hlist_head *chain;
+	struct hlist_head *odst;
+	struct hlist_node *newpos;
+	int i;
+	int dir;
+	unsigned seq;
+	u8 lbits4, rbits4, lbits6, rbits6;
+
+	mutex_lock(&hash_resize_mutex);
+
+	/* read selector prefixlen thresholds */
+	do {
+		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
+
+		lbits4 = net->xfrm.policy_hthresh.lbits4;
+		rbits4 = net->xfrm.policy_hthresh.rbits4;
+		lbits6 = net->xfrm.policy_hthresh.lbits6;
+		rbits6 = net->xfrm.policy_hthresh.rbits6;
+	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+
+	/* reset the bydst and inexact table in all directions */
+	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
+		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
+		hmask = net->xfrm.policy_bydst[dir].hmask;
+		odst = net->xfrm.policy_bydst[dir].table;
+		for (i = hmask; i >= 0; i--)
+			INIT_HLIST_HEAD(odst + i);
+		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
+			/* dir out => dst = remote, src = local */
+			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
+			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
+			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
+			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
+		} else {
+			/* dir in/fwd => dst = local, src = remote */
+			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
+			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
+			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
+			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
+		}
+	}
+
+	/* re-insert all policies by order of creation */
+	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
+		newpos = NULL;
+		chain = policy_hash_bysel(net, &policy->selector,
+					  policy->family,
+					  xfrm_policy_id2dir(policy->index));
+		hlist_for_each_entry(pol, chain, bydst) {
+			if (policy->priority >= pol->priority)
+				newpos = &pol->bydst;
+			else
+				break;
+		}
+		if (newpos)
+			hlist_add_behind(&policy->bydst, newpos);
+		else
+			hlist_add_head(&policy->bydst, chain);
+	}
+
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	mutex_unlock(&hash_resize_mutex);
+}
+
+void xfrm_policy_hash_rebuild(struct net *net)
+{
+	schedule_work(&net->xfrm.policy_hthresh.work);
+}
+EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
+
+/* Generate new index... KAME seems to generate them ordered by cost
+ * of an absolute inpredictability of ordering of rules. This will not pass. */
+static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
+{
+	static u32 idx_generator;
+
+	for (;;) {
+		struct hlist_head *list;
+		struct xfrm_policy *p;
+		u32 idx;
+		int found;
+
+		if (!index) {
+			idx = (idx_generator | dir);
+			idx_generator += 8;
+		} else {
+			idx = index;
+			index = 0;
+		}
+
+		if (idx == 0)
+			idx = 8;
+		list = net->xfrm.policy_byidx + idx_hash(net, idx);
+		found = 0;
+		hlist_for_each_entry(p, list, byidx) {
+			if (p->index == idx) {
+				found = 1;
+				break;
+			}
+		}
+		if (!found)
+			return idx;
+	}
+}
+
+static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
+{
+	u32 *p1 = (u32 *) s1;
+	u32 *p2 = (u32 *) s2;
+	int len = sizeof(struct xfrm_selector) / sizeof(u32);
+	int i;
+
+	for (i = 0; i < len; i++) {
+		if (p1[i] != p2[i])
+			return 1;
+	}
+
+	return 0;
+}
+
+static void xfrm_policy_requeue(struct xfrm_policy *old,
+				struct xfrm_policy *new)
+{
+	struct xfrm_policy_queue *pq = &old->polq;
+	struct sk_buff_head list;
+
+	__skb_queue_head_init(&list);
+
+	spin_lock_bh(&pq->hold_queue.lock);
+	skb_queue_splice_init(&pq->hold_queue, &list);
+	if (del_timer(&pq->hold_timer))
+		xfrm_pol_put(old);
+	spin_unlock_bh(&pq->hold_queue.lock);
+
+	if (skb_queue_empty(&list))
+		return;
+
+	pq = &new->polq;
+
+	spin_lock_bh(&pq->hold_queue.lock);
+	skb_queue_splice(&list, &pq->hold_queue);
+	pq->timeout = XFRM_QUEUE_TMO_MIN;
+	if (!mod_timer(&pq->hold_timer, jiffies))
+		xfrm_pol_hold(new);
+	spin_unlock_bh(&pq->hold_queue.lock);
+}
+
+static bool xfrm_policy_mark_match(struct xfrm_policy *policy,
+				   struct xfrm_policy *pol)
+{
+	u32 mark = policy->mark.v & policy->mark.m;
+
+	if (policy->mark.v == pol->mark.v && policy->mark.m == pol->mark.m)
+		return true;
+
+	if ((mark & pol->mark.m) == pol->mark.v &&
+	    policy->priority == pol->priority)
+		return true;
+
+	return false;
+}
+
+int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
+{
+	struct net *net = xp_net(policy);
+	struct xfrm_policy *pol;
+	struct xfrm_policy *delpol;
+	struct hlist_head *chain;
+	struct hlist_node *newpos;
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+	chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
+	delpol = NULL;
+	newpos = NULL;
+	hlist_for_each_entry(pol, chain, bydst) {
+		if (pol->type == policy->type &&
+		    !selector_cmp(&pol->selector, &policy->selector) &&
+		    xfrm_policy_mark_match(policy, pol) &&
+		    xfrm_sec_ctx_match(pol->security, policy->security) &&
+		    !WARN_ON(delpol)) {
+			if (excl) {
+				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+				return -EEXIST;
+			}
+			delpol = pol;
+			if (policy->priority > pol->priority)
+				continue;
+		} else if (policy->priority >= pol->priority) {
+			newpos = &pol->bydst;
+			continue;
+		}
+		if (delpol)
+			break;
+	}
+	if (newpos)
+		hlist_add_behind(&policy->bydst, newpos);
+	else
+		hlist_add_head(&policy->bydst, chain);
+	__xfrm_policy_link(policy, dir);
+	atomic_inc(&net->xfrm.flow_cache_genid);
+
+	/* After previous checking, family can either be AF_INET or AF_INET6 */
+	if (policy->family == AF_INET)
+		rt_genid_bump_ipv4(net);
+	else
+		rt_genid_bump_ipv6(net);
+
+	if (delpol) {
+		xfrm_policy_requeue(delpol, policy);
+		__xfrm_policy_unlink(delpol, dir);
+	}
+	policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
+	hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
+	policy->curlft.add_time = get_seconds();
+	policy->curlft.use_time = 0;
+	if (!mod_timer(&policy->timer, jiffies + HZ))
+		xfrm_pol_hold(policy);
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	if (delpol)
+		xfrm_policy_kill(delpol);
+	else if (xfrm_bydst_should_resize(net, dir, NULL))
+		schedule_work(&net->xfrm.policy_hash_work);
+
+	return 0;
+}
+EXPORT_SYMBOL(xfrm_policy_insert);
+
+struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
+					  int dir, struct xfrm_selector *sel,
+					  struct xfrm_sec_ctx *ctx, int delete,
+					  int *err)
+{
+	struct xfrm_policy *pol, *ret;
+	struct hlist_head *chain;
+
+	*err = 0;
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+	chain = policy_hash_bysel(net, sel, sel->family, dir);
+	ret = NULL;
+	hlist_for_each_entry(pol, chain, bydst) {
+		if (pol->type == type &&
+		    (mark & pol->mark.m) == pol->mark.v &&
+		    !selector_cmp(sel, &pol->selector) &&
+		    xfrm_sec_ctx_match(ctx, pol->security)) {
+			xfrm_pol_hold(pol);
+			if (delete) {
+				*err = security_xfrm_policy_delete(
+								pol->security);
+				if (*err) {
+					write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+					return pol;
+				}
+				__xfrm_policy_unlink(pol, dir);
+			}
+			ret = pol;
+			break;
+		}
+	}
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	if (ret && delete)
+		xfrm_policy_kill(ret);
+	return ret;
+}
+EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
+
+struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
+				     int dir, u32 id, int delete, int *err)
+{
+	struct xfrm_policy *pol, *ret;
+	struct hlist_head *chain;
+
+	*err = -ENOENT;
+	if (xfrm_policy_id2dir(id) != dir)
+		return NULL;
+
+	*err = 0;
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+	chain = net->xfrm.policy_byidx + idx_hash(net, id);
+	ret = NULL;
+	hlist_for_each_entry(pol, chain, byidx) {
+		if (pol->type == type && pol->index == id &&
+		    (mark & pol->mark.m) == pol->mark.v) {
+			xfrm_pol_hold(pol);
+			if (delete) {
+				*err = security_xfrm_policy_delete(
+								pol->security);
+				if (*err) {
+					write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+					return pol;
+				}
+				__xfrm_policy_unlink(pol, dir);
+			}
+			ret = pol;
+			break;
+		}
+	}
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	if (ret && delete)
+		xfrm_policy_kill(ret);
+	return ret;
+}
+EXPORT_SYMBOL(xfrm_policy_byid);
+
+#ifdef CONFIG_SECURITY_NETWORK_XFRM
+static inline int
+xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
+{
+	int dir, err = 0;
+
+	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
+		struct xfrm_policy *pol;
+		int i;
+
+		hlist_for_each_entry(pol,
+				     &net->xfrm.policy_inexact[dir], bydst) {
+			if (pol->type != type)
+				continue;
+			err = security_xfrm_policy_delete(pol->security);
+			if (err) {
+				xfrm_audit_policy_delete(pol, 0, task_valid);
+				return err;
+			}
+		}
+		for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
+			hlist_for_each_entry(pol,
+					     net->xfrm.policy_bydst[dir].table + i,
+					     bydst) {
+				if (pol->type != type)
+					continue;
+				err = security_xfrm_policy_delete(
+								pol->security);
+				if (err) {
+					xfrm_audit_policy_delete(pol, 0,
+								 task_valid);
+					return err;
+				}
+			}
+		}
+	}
+	return err;
+}
+#else
+static inline int
+xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
+{
+	return 0;
+}
+#endif
+
+int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
+{
+	int dir, err = 0, cnt = 0;
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+
+	err = xfrm_policy_flush_secctx_check(net, type, task_valid);
+	if (err)
+		goto out;
+
+	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
+		struct xfrm_policy *pol;
+		int i;
+
+	again1:
+		hlist_for_each_entry(pol,
+				     &net->xfrm.policy_inexact[dir], bydst) {
+			if (pol->type != type)
+				continue;
+			__xfrm_policy_unlink(pol, dir);
+			write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+			cnt++;
+
+			xfrm_audit_policy_delete(pol, 1, task_valid);
+
+			xfrm_policy_kill(pol);
+
+			write_lock_bh(&net->xfrm.xfrm_policy_lock);
+			goto again1;
+		}
+
+		for (i = net->xfrm.policy_bydst[dir].hmask; i >= 0; i--) {
+	again2:
+			hlist_for_each_entry(pol,
+					     net->xfrm.policy_bydst[dir].table + i,
+					     bydst) {
+				if (pol->type != type)
+					continue;
+				__xfrm_policy_unlink(pol, dir);
+				write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+				cnt++;
+
+				xfrm_audit_policy_delete(pol, 1, task_valid);
+				xfrm_policy_kill(pol);
+
+				write_lock_bh(&net->xfrm.xfrm_policy_lock);
+				goto again2;
+			}
+		}
+
+	}
+	if (!cnt)
+		err = -ESRCH;
+out:
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+	return err;
+}
+EXPORT_SYMBOL(xfrm_policy_flush);
+
+int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
+		     int (*func)(struct xfrm_policy *, int, int, void*),
+		     void *data)
+{
+	struct xfrm_policy *pol;
+	struct xfrm_policy_walk_entry *x;
+	int error = 0;
+
+	if (walk->type >= XFRM_POLICY_TYPE_MAX &&
+	    walk->type != XFRM_POLICY_TYPE_ANY)
+		return -EINVAL;
+
+	if (list_empty(&walk->walk.all) && walk->seq != 0)
+		return 0;
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+	if (list_empty(&walk->walk.all))
+		x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
+	else
+		x = list_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all);
+	list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
+		if (x->dead)
+			continue;
+		pol = container_of(x, struct xfrm_policy, walk);
+		if (walk->type != XFRM_POLICY_TYPE_ANY &&
+		    walk->type != pol->type)
+			continue;
+		error = func(pol, xfrm_policy_id2dir(pol->index),
+			     walk->seq, data);
+		if (error) {
+			list_move_tail(&walk->walk.all, &x->all);
+			goto out;
+		}
+		walk->seq++;
+	}
+	if (walk->seq == 0) {
+		error = -ENOENT;
+		goto out;
+	}
+	list_del_init(&walk->walk.all);
+out:
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+	return error;
+}
+EXPORT_SYMBOL(xfrm_policy_walk);
+
+void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
+{
+	INIT_LIST_HEAD(&walk->walk.all);
+	walk->walk.dead = 1;
+	walk->type = type;
+	walk->seq = 0;
+}
+EXPORT_SYMBOL(xfrm_policy_walk_init);
+
+void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
+{
+	if (list_empty(&walk->walk.all))
+		return;
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
+	list_del(&walk->walk.all);
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+}
+EXPORT_SYMBOL(xfrm_policy_walk_done);
+
+/*
+ * Find policy to apply to this flow.
+ *
+ * Returns 0 if policy found, else an -errno.
+ */
+static int xfrm_policy_match(const struct xfrm_policy *pol,
+			     const struct flowi *fl,
+			     u8 type, u16 family, int dir)
+{
+	const struct xfrm_selector *sel = &pol->selector;
+	int ret = -ESRCH;
+	bool match;
+
+	if (pol->family != family ||
+	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
+	    pol->type != type)
+		return ret;
+
+	match = xfrm_selector_match(sel, fl, family);
+	if (match)
+		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
+						  dir);
+
+	return ret;
+}
+
+static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
+						     const struct flowi *fl,
+						     u16 family, u8 dir)
+{
+	int err;
+	struct xfrm_policy *pol, *ret;
+	const xfrm_address_t *daddr, *saddr;
+	struct hlist_head *chain;
+	u32 priority = ~0U;
+
+	daddr = xfrm_flowi_daddr(fl, family);
+	saddr = xfrm_flowi_saddr(fl, family);
+	if (unlikely(!daddr || !saddr))
+		return NULL;
+
+	read_lock_bh(&net->xfrm.xfrm_policy_lock);
+	chain = policy_hash_direct(net, daddr, saddr, family, dir);
+	ret = NULL;
+	hlist_for_each_entry(pol, chain, bydst) {
+		err = xfrm_policy_match(pol, fl, type, family, dir);
+		if (err) {
+			if (err == -ESRCH)
+				continue;
+			else {
+				ret = ERR_PTR(err);
+				goto fail;
+			}
+		} else {
+			ret = pol;
+			priority = ret->priority;
+			break;
+		}
+	}
+	chain = &net->xfrm.policy_inexact[dir];
+	hlist_for_each_entry(pol, chain, bydst) {
+		err = xfrm_policy_match(pol, fl, type, family, dir);
+		if (err) {
+			if (err == -ESRCH)
+				continue;
+			else {
+				ret = ERR_PTR(err);
+				goto fail;
+			}
+		} else if (pol->priority < priority) {
+			ret = pol;
+			break;
+		}
+	}
+	if (ret)
+		xfrm_pol_hold(ret);
+fail:
+	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	return ret;
+}
+
+static struct xfrm_policy *
+__xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
+{
+#ifdef CONFIG_XFRM_SUB_POLICY
+	struct xfrm_policy *pol;
+
+	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir);
+	if (pol != NULL)
+		return pol;
+#endif
+	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir);
+}
+
+static int flow_to_policy_dir(int dir)
+{
+	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
+	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
+	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
+		return dir;
+
+	switch (dir) {
+	default:
+	case FLOW_DIR_IN:
+		return XFRM_POLICY_IN;
+	case FLOW_DIR_OUT:
+		return XFRM_POLICY_OUT;
+	case FLOW_DIR_FWD:
+		return XFRM_POLICY_FWD;
+	}
+}
+
+static struct flow_cache_object *
+xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
+		   u8 dir, struct flow_cache_object *old_obj, void *ctx)
+{
+	struct xfrm_policy *pol;
+
+	if (old_obj)
+		xfrm_pol_put(container_of(old_obj, struct xfrm_policy, flo));
+
+	pol = __xfrm_policy_lookup(net, fl, family, flow_to_policy_dir(dir));
+	if (IS_ERR_OR_NULL(pol))
+		return ERR_CAST(pol);
+
+	/* Resolver returns two references:
+	 * one for cache and one for caller of flow_cache_lookup() */
+	xfrm_pol_hold(pol);
+
+	return &pol->flo;
+}
+
+static inline int policy_to_flow_dir(int dir)
+{
+	if (XFRM_POLICY_IN == FLOW_DIR_IN &&
+	    XFRM_POLICY_OUT == FLOW_DIR_OUT &&
+	    XFRM_POLICY_FWD == FLOW_DIR_FWD)
+		return dir;
+	switch (dir) {
+	default:
+	case XFRM_POLICY_IN:
+		return FLOW_DIR_IN;
+	case XFRM_POLICY_OUT:
+		return FLOW_DIR_OUT;
+	case XFRM_POLICY_FWD:
+		return FLOW_DIR_FWD;
+	}
+}
+
+static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
+						 const struct flowi *fl)
+{
+	struct xfrm_policy *pol;
+	struct net *net = sock_net(sk);
+
+	read_lock_bh(&net->xfrm.xfrm_policy_lock);
+	if ((pol = sk->sk_policy[dir]) != NULL) {
+		bool match = xfrm_selector_match(&pol->selector, fl,
+						 sk->sk_family);
+		int err = 0;
+
+		if (match) {
+			if ((sk->sk_mark & pol->mark.m) != pol->mark.v) {
+				pol = NULL;
+				goto out;
+			}
+			err = security_xfrm_policy_lookup(pol->security,
+						      fl->flowi_secid,
+						      policy_to_flow_dir(dir));
+			if (!err)
+				xfrm_pol_hold(pol);
+			else if (err == -ESRCH)
+				pol = NULL;
+			else
+				pol = ERR_PTR(err);
+		} else
+			pol = NULL;
+	}
+out:
+	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+	return pol;
+}
+
+static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
+{
+	struct net *net = xp_net(pol);
+
+	list_add(&pol->walk.all, &net->xfrm.policy_all);
+	net->xfrm.policy_count[dir]++;
+	xfrm_pol_hold(pol);
+}
+
+static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
+						int dir)
+{
+	struct net *net = xp_net(pol);
+
+	if (list_empty(&pol->walk.all))
+		return NULL;
+
+	/* Socket policies are not hashed. */
+	if (!hlist_unhashed(&pol->bydst)) {
+		hlist_del(&pol->bydst);
+		hlist_del(&pol->byidx);
+	}
+
+	list_del_init(&pol->walk.all);
+	net->xfrm.policy_count[dir]--;
+
+	return pol;
+}
+
+static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
+{
+	__xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
+}
+
+static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
+{
+	__xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
+}
+
+int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
+{
+	struct net *net = xp_net(pol);
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+	pol = __xfrm_policy_unlink(pol, dir);
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+	if (pol) {
+		xfrm_policy_kill(pol);
+		return 0;
+	}
+	return -ENOENT;
+}
+EXPORT_SYMBOL(xfrm_policy_delete);
+
+int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
+{
+	struct net *net = xp_net(pol);
+	struct xfrm_policy *old_pol;
+
+#ifdef CONFIG_XFRM_SUB_POLICY
+	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
+		return -EINVAL;
+#endif
+
+	write_lock_bh(&net->xfrm.xfrm_policy_lock);
+	old_pol = sk->sk_policy[dir];
+	sk->sk_policy[dir] = pol;
+	if (pol) {
+		pol->curlft.add_time = get_seconds();
+		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
+		xfrm_sk_policy_link(pol, dir);
+	}
+	if (old_pol) {
+		if (pol)
+			xfrm_policy_requeue(old_pol, pol);
+
+		/* Unlinking succeeds always. This is the only function
+		 * allowed to delete or replace socket policy.
+		 */
+		xfrm_sk_policy_unlink(old_pol, dir);
+	}
+	write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	if (old_pol) {
+		xfrm_policy_kill(old_pol);
+	}
+	return 0;
+}
+
+static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
+{
+	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
+	struct net *net = xp_net(old);
+
+	if (newp) {
+		newp->selector = old->selector;
+		if (security_xfrm_policy_clone(old->security,
+					       &newp->security)) {
+			kfree(newp);
+			return NULL;  /* ENOMEM */
+		}
+		newp->lft = old->lft;
+		newp->curlft = old->curlft;
+		newp->mark = old->mark;
+		newp->action = old->action;
+		newp->flags = old->flags;
+		newp->xfrm_nr = old->xfrm_nr;
+		newp->index = old->index;
+		newp->type = old->type;
+		memcpy(newp->xfrm_vec, old->xfrm_vec,
+		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
+		write_lock_bh(&net->xfrm.xfrm_policy_lock);
+		xfrm_sk_policy_link(newp, dir);
+		write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+		xfrm_pol_put(newp);
+	}
+	return newp;
+}
+
+int __xfrm_sk_clone_policy(struct sock *sk)
+{
+	struct xfrm_policy *p0 = sk->sk_policy[0],
+			   *p1 = sk->sk_policy[1];
+
+	sk->sk_policy[0] = sk->sk_policy[1] = NULL;
+	if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
+		return -ENOMEM;
+	if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+static int
+xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
+	       unsigned short family)
+{
+	int err;
+	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+
+	if (unlikely(afinfo == NULL))
+		return -EINVAL;
+	err = afinfo->get_saddr(net, local, remote);
+	xfrm_policy_put_afinfo(afinfo);
+	return err;
+}
+
+/* Resolve list of templates for the flow, given policy. */
+
+static int
+xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
+		      struct xfrm_state **xfrm, unsigned short family)
+{
+	struct net *net = xp_net(policy);
+	int nx;
+	int i, error;
+	xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
+	xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
+	xfrm_address_t tmp;
+
+	for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
+		struct xfrm_state *x;
+		xfrm_address_t *remote = daddr;
+		xfrm_address_t *local  = saddr;
+		struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
+
+		if (tmpl->mode == XFRM_MODE_TUNNEL ||
+		    tmpl->mode == XFRM_MODE_BEET) {
+			remote = &tmpl->id.daddr;
+			local = &tmpl->saddr;
+			if (xfrm_addr_any(local, tmpl->encap_family)) {
+				error = xfrm_get_saddr(net, &tmp, remote, tmpl->encap_family);
+				if (error)
+					goto fail;
+				local = &tmp;
+			}
+		}
+
+		x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family);
+
+		if (x && x->km.state == XFRM_STATE_VALID) {
+			xfrm[nx++] = x;
+			daddr = remote;
+			saddr = local;
+			continue;
+		}
+		if (x) {
+			error = (x->km.state == XFRM_STATE_ERROR ?
+				 -EINVAL : -EAGAIN);
+			xfrm_state_put(x);
+		} else if (error == -ESRCH) {
+			error = -EAGAIN;
+		}
+
+		if (!tmpl->optional)
+			goto fail;
+	}
+	return nx;
+
+fail:
+	for (nx--; nx >= 0; nx--)
+		xfrm_state_put(xfrm[nx]);
+	return error;
+}
+
+static int
+xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
+		  struct xfrm_state **xfrm, unsigned short family)
+{
+	struct xfrm_state *tp[XFRM_MAX_DEPTH];
+	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
+	int cnx = 0;
+	int error;
+	int ret;
+	int i;
+
+	for (i = 0; i < npols; i++) {
+		if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
+			error = -ENOBUFS;
+			goto fail;
+		}
+
+		ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
+		if (ret < 0) {
+			error = ret;
+			goto fail;
+		} else
+			cnx += ret;
+	}
+
+	/* found states are sorted for outbound processing */
+	if (npols > 1)
+		xfrm_state_sort(xfrm, tpp, cnx, family);
+
+	return cnx;
+
+ fail:
+	for (cnx--; cnx >= 0; cnx--)
+		xfrm_state_put(tpp[cnx]);
+	return error;
+
+}
+
+/* Check that the bundle accepts the flow and its components are
+ * still valid.
+ */
+
+static inline int xfrm_get_tos(const struct flowi *fl, int family)
+{
+	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	int tos;
+
+	if (!afinfo)
+		return -EINVAL;
+
+	tos = afinfo->get_tos(fl);
+
+	xfrm_policy_put_afinfo(afinfo);
+
+	return tos;
+}
+
+static struct flow_cache_object *xfrm_bundle_flo_get(struct flow_cache_object *flo)
+{
+	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
+	struct dst_entry *dst = &xdst->u.dst;
+
+	if (xdst->route == NULL) {
+		/* Dummy bundle - if it has xfrms we were not
+		 * able to build bundle as template resolution failed.
+		 * It means we need to try again resolving. */
+		if (xdst->num_xfrms > 0)
+			return NULL;
+	} else if (dst->flags & DST_XFRM_QUEUE) {
+		return NULL;
+	} else {
+		/* Real bundle */
+		if (stale_bundle(dst))
+			return NULL;
+	}
+
+	dst_hold(dst);
+	return flo;
+}
+
+static int xfrm_bundle_flo_check(struct flow_cache_object *flo)
+{
+	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
+	struct dst_entry *dst = &xdst->u.dst;
+
+	if (!xdst->route)
+		return 0;
+	if (stale_bundle(dst))
+		return 0;
+
+	return 1;
+}
+
+static void xfrm_bundle_flo_delete(struct flow_cache_object *flo)
+{
+	struct xfrm_dst *xdst = container_of(flo, struct xfrm_dst, flo);
+	struct dst_entry *dst = &xdst->u.dst;
+
+	dst_free(dst);
+}
+
+static const struct flow_cache_ops xfrm_bundle_fc_ops = {
+	.get = xfrm_bundle_flo_get,
+	.check = xfrm_bundle_flo_check,
+	.delete = xfrm_bundle_flo_delete,
+};
+
+static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
+{
+	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	struct dst_ops *dst_ops;
+	struct xfrm_dst *xdst;
+
+	if (!afinfo)
+		return ERR_PTR(-EINVAL);
+
+	switch (family) {
+	case AF_INET:
+		dst_ops = &net->xfrm.xfrm4_dst_ops;
+		break;
+#if IS_ENABLED(CONFIG_IPV6)
+	case AF_INET6:
+		dst_ops = &net->xfrm.xfrm6_dst_ops;
+		break;
+#endif
+	default:
+		BUG();
+	}
+	xdst = dst_alloc(dst_ops, NULL, 0, DST_OBSOLETE_NONE, 0);
+
+	if (likely(xdst)) {
+		struct dst_entry *dst = &xdst->u.dst;
+
+		memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst));
+		xdst->flo.ops = &xfrm_bundle_fc_ops;
+		if (afinfo->init_dst)
+			afinfo->init_dst(net, xdst);
+	} else
+		xdst = ERR_PTR(-ENOBUFS);
+
+	xfrm_policy_put_afinfo(afinfo);
+
+	return xdst;
+}
+
+static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
+				 int nfheader_len)
+{
+	struct xfrm_policy_afinfo *afinfo =
+		xfrm_policy_get_afinfo(dst->ops->family);
+	int err;
+
+	if (!afinfo)
+		return -EINVAL;
+
+	err = afinfo->init_path(path, dst, nfheader_len);
+
+	xfrm_policy_put_afinfo(afinfo);
+
+	return err;
+}
+
+static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
+				const struct flowi *fl)
+{
+	struct xfrm_policy_afinfo *afinfo =
+		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
+	int err;
+
+	if (!afinfo)
+		return -EINVAL;
+
+	err = afinfo->fill_dst(xdst, dev, fl);
+
+	xfrm_policy_put_afinfo(afinfo);
+
+	return err;
+}
+
+
+/* Allocate chain of dst_entry's, attach known xfrm's, calculate
+ * all the metrics... Shortly, bundle a bundle.
+ */
+
+static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
+					    struct xfrm_state **xfrm, int nx,
+					    const struct flowi *fl,
+					    struct dst_entry *dst)
+{
+	struct net *net = xp_net(policy);
+	unsigned long now = jiffies;
+	struct net_device *dev;
+	struct xfrm_mode *inner_mode;
+	struct dst_entry *dst_prev = NULL;
+	struct dst_entry *dst0 = NULL;
+	int i = 0;
+	int err;
+	int header_len = 0;
+	int nfheader_len = 0;
+	int trailer_len = 0;
+	int tos;
+	int family = policy->selector.family;
+	xfrm_address_t saddr, daddr;
+
+	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
+
+	tos = xfrm_get_tos(fl, family);
+	err = tos;
+	if (tos < 0)
+		goto put_states;
+
+	dst_hold(dst);
+
+	for (; i < nx; i++) {
+		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
+		struct dst_entry *dst1 = &xdst->u.dst;
+
+		err = PTR_ERR(xdst);
+		if (IS_ERR(xdst)) {
+			dst_release(dst);
+			goto put_states;
+		}
+
+		if (xfrm[i]->sel.family == AF_UNSPEC) {
+			inner_mode = xfrm_ip2inner_mode(xfrm[i],
+							xfrm_af2proto(family));
+			if (!inner_mode) {
+				err = -EAFNOSUPPORT;
+				dst_release(dst);
+				goto put_states;
+			}
+		} else
+			inner_mode = xfrm[i]->inner_mode;
+
+		if (!dst_prev)
+			dst0 = dst1;
+		else {
+			dst_prev->child = dst_clone(dst1);
+			dst1->flags |= DST_NOHASH;
+		}
+
+		xdst->route = dst;
+		dst_copy_metrics(dst1, dst);
+
+		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
+			family = xfrm[i]->props.family;
+			dst = xfrm_dst_lookup(xfrm[i], tos, &saddr, &daddr,
+					      family);
+			err = PTR_ERR(dst);
+			if (IS_ERR(dst))
+				goto put_states;
+		} else
+			dst_hold(dst);
+
+		dst1->xfrm = xfrm[i];
+		xdst->xfrm_genid = xfrm[i]->genid;
+
+		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
+		dst1->flags |= DST_HOST;
+		dst1->lastuse = now;
+
+		dst1->input = dst_discard;
+		dst1->output = inner_mode->afinfo->output;
+
+		dst1->next = dst_prev;
+		dst_prev = dst1;
+
+		header_len += xfrm[i]->props.header_len;
+		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
+			nfheader_len += xfrm[i]->props.header_len;
+		trailer_len += xfrm[i]->props.trailer_len;
+	}
+
+	dst_prev->child = dst;
+	dst0->path = dst;
+
+	err = -ENODEV;
+	dev = dst->dev;
+	if (!dev)
+		goto free_dst;
+
+	xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
+	xfrm_init_pmtu(dst_prev);
+
+	for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {
+		struct xfrm_dst *xdst = (struct xfrm_dst *)dst_prev;
+
+		err = xfrm_fill_dst(xdst, dev, fl);
+		if (err)
+			goto free_dst;
+
+		dst_prev->header_len = header_len;
+		dst_prev->trailer_len = trailer_len;
+		header_len -= xdst->u.dst.xfrm->props.header_len;
+		trailer_len -= xdst->u.dst.xfrm->props.trailer_len;
+	}
+
+out:
+	return dst0;
+
+put_states:
+	for (; i < nx; i++)
+		xfrm_state_put(xfrm[i]);
+free_dst:
+	if (dst0)
+		dst_free(dst0);
+	dst0 = ERR_PTR(err);
+	goto out;
+}
+
+#ifdef CONFIG_XFRM_SUB_POLICY
+static int xfrm_dst_alloc_copy(void **target, const void *src, int size)
+{
+	if (!*target) {
+		*target = kmalloc(size, GFP_ATOMIC);
+		if (!*target)
+			return -ENOMEM;
+	}
+
+	memcpy(*target, src, size);
+	return 0;
+}
+#endif
+
+static int xfrm_dst_update_parent(struct dst_entry *dst,
+				  const struct xfrm_selector *sel)
+{
+#ifdef CONFIG_XFRM_SUB_POLICY
+	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+	return xfrm_dst_alloc_copy((void **)&(xdst->partner),
+				   sel, sizeof(*sel));
+#else
+	return 0;
+#endif
+}
+
+static int xfrm_dst_update_origin(struct dst_entry *dst,
+				  const struct flowi *fl)
+{
+#ifdef CONFIG_XFRM_SUB_POLICY
+	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+	return xfrm_dst_alloc_copy((void **)&(xdst->origin), fl, sizeof(*fl));
+#else
+	return 0;
+#endif
+}
+
+static int xfrm_expand_policies(const struct flowi *fl, u16 family,
+				struct xfrm_policy **pols,
+				int *num_pols, int *num_xfrms)
+{
+	int i;
+
+	if (*num_pols == 0 || !pols[0]) {
+		*num_pols = 0;
+		*num_xfrms = 0;
+		return 0;
+	}
+	if (IS_ERR(pols[0]))
+		return PTR_ERR(pols[0]);
+
+	*num_xfrms = pols[0]->xfrm_nr;
+
+#ifdef CONFIG_XFRM_SUB_POLICY
+	if (pols[0] && pols[0]->action == XFRM_POLICY_ALLOW &&
+	    pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
+		pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
+						    XFRM_POLICY_TYPE_MAIN,
+						    fl, family,
+						    XFRM_POLICY_OUT);
+		if (pols[1]) {
+			if (IS_ERR(pols[1])) {
+				xfrm_pols_put(pols, *num_pols);
+				return PTR_ERR(pols[1]);
+			}
+			(*num_pols)++;
+			(*num_xfrms) += pols[1]->xfrm_nr;
+		}
+	}
+#endif
+	for (i = 0; i < *num_pols; i++) {
+		if (pols[i]->action != XFRM_POLICY_ALLOW) {
+			*num_xfrms = -1;
+			break;
+		}
+	}
+
+	return 0;
+
+}
+
+static struct xfrm_dst *
+xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
+			       const struct flowi *fl, u16 family,
+			       struct dst_entry *dst_orig)
+{
+	struct net *net = xp_net(pols[0]);
+	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
+	struct dst_entry *dst;
+	struct xfrm_dst *xdst;
+	int err;
+
+	/* Try to instantiate a bundle */
+	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
+	if (err <= 0) {
+		if (err != 0 && err != -EAGAIN)
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
+		return ERR_PTR(err);
+	}
+
+	dst = xfrm_bundle_create(pols[0], xfrm, err, fl, dst_orig);
+	if (IS_ERR(dst)) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
+		return ERR_CAST(dst);
+	}
+
+	xdst = (struct xfrm_dst *)dst;
+	xdst->num_xfrms = err;
+	if (num_pols > 1)
+		err = xfrm_dst_update_parent(dst, &pols[1]->selector);
+	else
+		err = xfrm_dst_update_origin(dst, fl);
+	if (unlikely(err)) {
+		dst_free(dst);
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLECHECKERROR);
+		return ERR_PTR(err);
+	}
+
+	xdst->num_pols = num_pols;
+	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
+	xdst->policy_genid = atomic_read(&pols[0]->genid);
+
+	return xdst;
+}
+
+static void xfrm_policy_queue_process(unsigned long arg)
+{
+	struct sk_buff *skb;
+	struct sock *sk;
+	struct dst_entry *dst;
+	struct xfrm_policy *pol = (struct xfrm_policy *)arg;
+	struct xfrm_policy_queue *pq = &pol->polq;
+	struct flowi fl;
+	struct sk_buff_head list;
+
+	spin_lock(&pq->hold_queue.lock);
+	skb = skb_peek(&pq->hold_queue);
+	if (!skb) {
+		spin_unlock(&pq->hold_queue.lock);
+		goto out;
+	}
+	dst = skb_dst(skb);
+	sk = skb->sk;
+	xfrm_decode_session(skb, &fl, dst->ops->family);
+	spin_unlock(&pq->hold_queue.lock);
+
+	dst_hold(dst->path);
+	dst = xfrm_lookup(xp_net(pol), dst->path, &fl,
+			  sk, 0);
+	if (IS_ERR(dst))
+		goto purge_queue;
+
+	if (dst->flags & DST_XFRM_QUEUE) {
+		dst_release(dst);
+
+		if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
+			goto purge_queue;
+
+		pq->timeout = pq->timeout << 1;
+		if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
+			xfrm_pol_hold(pol);
+	goto out;
+	}
+
+	dst_release(dst);
+
+	__skb_queue_head_init(&list);
+
+	spin_lock(&pq->hold_queue.lock);
+	pq->timeout = 0;
+	skb_queue_splice_init(&pq->hold_queue, &list);
+	spin_unlock(&pq->hold_queue.lock);
+
+	while (!skb_queue_empty(&list)) {
+		skb = __skb_dequeue(&list);
+
+		xfrm_decode_session(skb, &fl, skb_dst(skb)->ops->family);
+		dst_hold(skb_dst(skb)->path);
+		dst = xfrm_lookup(xp_net(pol), skb_dst(skb)->path,
+				  &fl, skb->sk, 0);
+		if (IS_ERR(dst)) {
+			kfree_skb(skb);
+			continue;
+		}
+
+		nf_reset(skb);
+		skb_dst_drop(skb);
+		skb_dst_set(skb, dst);
+
+		dst_output(skb);
+	}
+
+out:
+	xfrm_pol_put(pol);
+	return;
+
+purge_queue:
+	pq->timeout = 0;
+	xfrm_queue_purge(&pq->hold_queue);
+	xfrm_pol_put(pol);
+}
+
+static int xdst_queue_output(struct sock *sk, struct sk_buff *skb)
+{
+	unsigned long sched_next;
+	struct dst_entry *dst = skb_dst(skb);
+	struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
+	struct xfrm_policy *pol = xdst->pols[0];
+	struct xfrm_policy_queue *pq = &pol->polq;
+
+	if (unlikely(skb_fclone_busy(sk, skb))) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
+		kfree_skb(skb);
+		return -EAGAIN;
+	}
+
+	skb_dst_force(skb);
+
+	spin_lock_bh(&pq->hold_queue.lock);
+
+	if (!pq->timeout)
+		pq->timeout = XFRM_QUEUE_TMO_MIN;
+
+	sched_next = jiffies + pq->timeout;
+
+	if (del_timer(&pq->hold_timer)) {
+		if (time_before(pq->hold_timer.expires, sched_next))
+			sched_next = pq->hold_timer.expires;
+		xfrm_pol_put(pol);
+	}
+
+	__skb_queue_tail(&pq->hold_queue, skb);
+	if (!mod_timer(&pq->hold_timer, sched_next))
+		xfrm_pol_hold(pol);
+
+	spin_unlock_bh(&pq->hold_queue.lock);
+
+	return 0;
+}
+
+static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
+						 struct xfrm_flo *xflo,
+						 const struct flowi *fl,
+						 int num_xfrms,
+						 u16 family)
+{
+	int err;
+	struct net_device *dev;
+	struct dst_entry *dst;
+	struct dst_entry *dst1;
+	struct xfrm_dst *xdst;
+
+	xdst = xfrm_alloc_dst(net, family);
+	if (IS_ERR(xdst))
+		return xdst;
+
+	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
+	    net->xfrm.sysctl_larval_drop ||
+	    num_xfrms <= 0)
+		return xdst;
+
+	dst = xflo->dst_orig;
+	dst1 = &xdst->u.dst;
+	dst_hold(dst);
+	xdst->route = dst;
+
+	dst_copy_metrics(dst1, dst);
+
+	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
+	dst1->flags |= DST_HOST | DST_XFRM_QUEUE;
+	dst1->lastuse = jiffies;
+
+	dst1->input = dst_discard;
+	dst1->output = xdst_queue_output;
+
+	dst_hold(dst);
+	dst1->child = dst;
+	dst1->path = dst;
+
+	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
+
+	err = -ENODEV;
+	dev = dst->dev;
+	if (!dev)
+		goto free_dst;
+
+	err = xfrm_fill_dst(xdst, dev, fl);
+	if (err)
+		goto free_dst;
+
+out:
+	return xdst;
+
+free_dst:
+	dst_release(dst1);
+	xdst = ERR_PTR(err);
+	goto out;
+}
+
+static struct flow_cache_object *
+xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
+		   struct flow_cache_object *oldflo, void *ctx)
+{
+	struct xfrm_flo *xflo = (struct xfrm_flo *)ctx;
+	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
+	struct xfrm_dst *xdst, *new_xdst;
+	int num_pols = 0, num_xfrms = 0, i, err, pol_dead;
+
+	/* Check if the policies from old bundle are usable */
+	xdst = NULL;
+	if (oldflo) {
+		xdst = container_of(oldflo, struct xfrm_dst, flo);
+		num_pols = xdst->num_pols;
+		num_xfrms = xdst->num_xfrms;
+		pol_dead = 0;
+		for (i = 0; i < num_pols; i++) {
+			pols[i] = xdst->pols[i];
+			pol_dead |= pols[i]->walk.dead;
+		}
+		if (pol_dead) {
+			dst_free(&xdst->u.dst);
+			xdst = NULL;
+			num_pols = 0;
+			num_xfrms = 0;
+			oldflo = NULL;
+		}
+	}
+
+	/* Resolve policies to use if we couldn't get them from
+	 * previous cache entry */
+	if (xdst == NULL) {
+		num_pols = 1;
+		pols[0] = __xfrm_policy_lookup(net, fl, family,
+					       flow_to_policy_dir(dir));
+		err = xfrm_expand_policies(fl, family, pols,
+					   &num_pols, &num_xfrms);
+		if (err < 0)
+			goto inc_error;
+		if (num_pols == 0)
+			return NULL;
+		if (num_xfrms <= 0)
+			goto make_dummy_bundle;
+	}
+
+	new_xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
+						  xflo->dst_orig);
+	if (IS_ERR(new_xdst)) {
+		err = PTR_ERR(new_xdst);
+		if (err != -EAGAIN)
+			goto error;
+		if (oldflo == NULL)
+			goto make_dummy_bundle;
+		dst_hold(&xdst->u.dst);
+		return oldflo;
+	} else if (new_xdst == NULL) {
+		num_xfrms = 0;
+		if (oldflo == NULL)
+			goto make_dummy_bundle;
+		xdst->num_xfrms = 0;
+		dst_hold(&xdst->u.dst);
+		return oldflo;
+	}
+
+	/* Kill the previous bundle */
+	if (xdst) {
+		/* The policies were stolen for newly generated bundle */
+		xdst->num_pols = 0;
+		dst_free(&xdst->u.dst);
+	}
+
+	/* Flow cache does not have reference, it dst_free()'s,
+	 * but we do need to return one reference for original caller */
+	dst_hold(&new_xdst->u.dst);
+	return &new_xdst->flo;
+
+make_dummy_bundle:
+	/* We found policies, but there's no bundles to instantiate:
+	 * either because the policy blocks, has no transformations or
+	 * we could not build template (no xfrm_states).*/
+	xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
+	if (IS_ERR(xdst)) {
+		xfrm_pols_put(pols, num_pols);
+		return ERR_CAST(xdst);
+	}
+	xdst->num_pols = num_pols;
+	xdst->num_xfrms = num_xfrms;
+	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
+
+	dst_hold(&xdst->u.dst);
+	return &xdst->flo;
+
+inc_error:
+	XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
+error:
+	if (xdst != NULL)
+		dst_free(&xdst->u.dst);
+	else
+		xfrm_pols_put(pols, num_pols);
+	return ERR_PTR(err);
+}
+
+static struct dst_entry *make_blackhole(struct net *net, u16 family,
+					struct dst_entry *dst_orig)
+{
+	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	struct dst_entry *ret;
+
+	if (!afinfo) {
+		dst_release(dst_orig);
+		return ERR_PTR(-EINVAL);
+	} else {
+		ret = afinfo->blackhole_route(net, dst_orig);
+	}
+	xfrm_policy_put_afinfo(afinfo);
+
+	return ret;
+}
+
+/* Main function: finds/creates a bundle for given flow.
+ *
+ * At the moment we eat a raw IP route. Mostly to speed up lookups
+ * on interfaces with disabled IPsec.
+ */
+struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
+			      const struct flowi *fl,
+			      struct sock *sk, int flags)
+{
+	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
+	struct flow_cache_object *flo;
+	struct xfrm_dst *xdst;
+	struct dst_entry *dst, *route;
+	u16 family = dst_orig->ops->family;
+	u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
+	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
+
+	dst = NULL;
+	xdst = NULL;
+	route = NULL;
+
+	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
+		num_pols = 1;
+		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
+		err = xfrm_expand_policies(fl, family, pols,
+					   &num_pols, &num_xfrms);
+		if (err < 0)
+			goto dropdst;
+
+		if (num_pols) {
+			if (num_xfrms <= 0) {
+				drop_pols = num_pols;
+				goto no_transform;
+			}
+
+			xdst = xfrm_resolve_and_create_bundle(
+					pols, num_pols, fl,
+					family, dst_orig);
+			if (IS_ERR(xdst)) {
+				xfrm_pols_put(pols, num_pols);
+				err = PTR_ERR(xdst);
+				goto dropdst;
+			} else if (xdst == NULL) {
+				num_xfrms = 0;
+				drop_pols = num_pols;
+				goto no_transform;
+			}
+
+			dst_hold(&xdst->u.dst);
+			xdst->u.dst.flags |= DST_NOCACHE;
+			route = xdst->route;
+		}
+	}
+
+	if (xdst == NULL) {
+		struct xfrm_flo xflo;
+
+		xflo.dst_orig = dst_orig;
+		xflo.flags = flags;
+
+		/* To accelerate a bit...  */
+		if ((dst_orig->flags & DST_NOXFRM) ||
+		    !net->xfrm.policy_count[XFRM_POLICY_OUT])
+			goto nopol;
+
+		flo = flow_cache_lookup(net, fl, family, dir,
+					xfrm_bundle_lookup, &xflo);
+		if (flo == NULL)
+			goto nopol;
+		if (IS_ERR(flo)) {
+			err = PTR_ERR(flo);
+			goto dropdst;
+		}
+		xdst = container_of(flo, struct xfrm_dst, flo);
+
+		num_pols = xdst->num_pols;
+		num_xfrms = xdst->num_xfrms;
+		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
+		route = xdst->route;
+	}
+
+	dst = &xdst->u.dst;
+	if (route == NULL && num_xfrms > 0) {
+		/* The only case when xfrm_bundle_lookup() returns a
+		 * bundle with null route, is when the template could
+		 * not be resolved. It means policies are there, but
+		 * bundle could not be created, since we don't yet
+		 * have the xfrm_state's. We need to wait for KM to
+		 * negotiate new SA's or bail out with error.*/
+		if (net->xfrm.sysctl_larval_drop) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
+			err = -EREMOTE;
+			goto error;
+		}
+
+		err = -EAGAIN;
+
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
+		goto error;
+	}
+
+no_transform:
+	if (num_pols == 0)
+		goto nopol;
+
+	if ((flags & XFRM_LOOKUP_ICMP) &&
+	    !(pols[0]->flags & XFRM_POLICY_ICMP)) {
+		err = -ENOENT;
+		goto error;
+	}
+
+	for (i = 0; i < num_pols; i++)
+		pols[i]->curlft.use_time = get_seconds();
+
+	if (num_xfrms < 0) {
+		/* Prohibit the flow */
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
+		err = -EPERM;
+		goto error;
+	} else if (num_xfrms > 0) {
+		/* Flow transformed */
+		dst_release(dst_orig);
+	} else {
+		/* Flow passes untransformed */
+		dst_release(dst);
+		dst = dst_orig;
+	}
+ok:
+	xfrm_pols_put(pols, drop_pols);
+	if (dst && dst->xfrm &&
+	    dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
+		dst->flags |= DST_XFRM_TUNNEL;
+	return dst;
+
+nopol:
+	if (!(flags & XFRM_LOOKUP_ICMP)) {
+		dst = dst_orig;
+		goto ok;
+	}
+	err = -ENOENT;
+error:
+	dst_release(dst);
+dropdst:
+	if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
+		dst_release(dst_orig);
+	xfrm_pols_put(pols, drop_pols);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL(xfrm_lookup);
+
+/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
+ * Otherwise we may send out blackholed packets.
+ */
+struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
+				    const struct flowi *fl,
+				    struct sock *sk, int flags)
+{
+	struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
+					    flags | XFRM_LOOKUP_QUEUE |
+					    XFRM_LOOKUP_KEEP_DST_REF);
+
+	if (IS_ERR(dst) && PTR_ERR(dst) == -EREMOTE)
+		return make_blackhole(net, dst_orig->ops->family, dst_orig);
+
+	return dst;
+}
+EXPORT_SYMBOL(xfrm_lookup_route);
+
+static inline int
+xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
+{
+	struct xfrm_state *x;
+
+	if (!skb->sp || idx < 0 || idx >= skb->sp->len)
+		return 0;
+	x = skb->sp->xvec[idx];
+	if (!x->type->reject)
+		return 0;
+	return x->type->reject(x, skb, fl);
+}
+
+/* When skb is transformed back to its "native" form, we have to
+ * check policy restrictions. At the moment we make this in maximally
+ * stupid way. Shame on me. :-) Of course, connected sockets must
+ * have policy cached at them.
+ */
+
+static inline int
+xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
+	      unsigned short family)
+{
+	if (xfrm_state_kern(x))
+		return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
+	return	x->id.proto == tmpl->id.proto &&
+		(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
+		(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
+		x->props.mode == tmpl->mode &&
+		(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
+		 !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
+		!(x->props.mode != XFRM_MODE_TRANSPORT &&
+		  xfrm_state_addr_cmp(tmpl, x, family));
+}
+
+/*
+ * 0 or more than 0 is returned when validation is succeeded (either bypass
+ * because of optional transport mode, or next index of the mathced secpath
+ * state with the template.
+ * -1 is returned when no matching template is found.
+ * Otherwise "-2 - errored_index" is returned.
+ */
+static inline int
+xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
+	       unsigned short family)
+{
+	int idx = start;
+
+	if (tmpl->optional) {
+		if (tmpl->mode == XFRM_MODE_TRANSPORT)
+			return start;
+	} else
+		start = -1;
+	for (; idx < sp->len; idx++) {
+		if (xfrm_state_ok(tmpl, sp->xvec[idx], family))
+			return ++idx;
+		if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
+			if (start == -1)
+				start = -2-idx;
+			break;
+		}
+	}
+	return start;
+}
+
+int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
+			  unsigned int family, int reverse)
+{
+	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	int err;
+
+	if (unlikely(afinfo == NULL))
+		return -EAFNOSUPPORT;
+
+	afinfo->decode_session(skb, fl, reverse);
+	err = security_xfrm_decode_session(skb, &fl->flowi_secid);
+	xfrm_policy_put_afinfo(afinfo);
+	return err;
+}
+EXPORT_SYMBOL(__xfrm_decode_session);
+
+static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
+{
+	for (; k < sp->len; k++) {
+		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
+			*idxp = k;
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
+			unsigned short family)
+{
+	struct net *net = dev_net(skb->dev);
+	struct xfrm_policy *pol;
+	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
+	int npols = 0;
+	int xfrm_nr;
+	int pi;
+	int reverse;
+	struct flowi fl;
+	u8 fl_dir;
+	int xerr_idx = -1;
+
+	reverse = dir & ~XFRM_POLICY_MASK;
+	dir &= XFRM_POLICY_MASK;
+	fl_dir = policy_to_flow_dir(dir);
+
+	if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
+		return 0;
+	}
+
+	nf_nat_decode_session(skb, &fl, family);
+
+	/* First, check used SA against their selectors. */
+	if (skb->sp) {
+		int i;
+
+		for (i = skb->sp->len-1; i >= 0; i--) {
+			struct xfrm_state *x = skb->sp->xvec[i];
+			if (!xfrm_selector_match(&x->sel, &fl, family)) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
+				return 0;
+			}
+		}
+	}
+
+	pol = NULL;
+	if (sk && sk->sk_policy[dir]) {
+		pol = xfrm_sk_policy_lookup(sk, dir, &fl);
+		if (IS_ERR(pol)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
+			return 0;
+		}
+	}
+
+	if (!pol) {
+		struct flow_cache_object *flo;
+
+		flo = flow_cache_lookup(net, &fl, family, fl_dir,
+					xfrm_policy_lookup, NULL);
+		if (IS_ERR_OR_NULL(flo))
+			pol = ERR_CAST(flo);
+		else
+			pol = container_of(flo, struct xfrm_policy, flo);
+	}
+
+	if (IS_ERR(pol)) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
+		return 0;
+	}
+
+	if (!pol) {
+		if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
+			xfrm_secpath_reject(xerr_idx, skb, &fl);
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
+			return 0;
+		}
+		return 1;
+	}
+
+	pol->curlft.use_time = get_seconds();
+
+	pols[0] = pol;
+	npols++;
+#ifdef CONFIG_XFRM_SUB_POLICY
+	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
+		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
+						    &fl, family,
+						    XFRM_POLICY_IN);
+		if (pols[1]) {
+			if (IS_ERR(pols[1])) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
+				return 0;
+			}
+			pols[1]->curlft.use_time = get_seconds();
+			npols++;
+		}
+	}
+#endif
+
+	if (pol->action == XFRM_POLICY_ALLOW) {
+		struct sec_path *sp;
+		static struct sec_path dummy;
+		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
+		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
+		struct xfrm_tmpl **tpp = tp;
+		int ti = 0;
+		int i, k;
+
+		if ((sp = skb->sp) == NULL)
+			sp = &dummy;
+
+		for (pi = 0; pi < npols; pi++) {
+			if (pols[pi] != pol &&
+			    pols[pi]->action != XFRM_POLICY_ALLOW) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
+				goto reject;
+			}
+			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
+				goto reject_error;
+			}
+			for (i = 0; i < pols[pi]->xfrm_nr; i++)
+				tpp[ti++] = &pols[pi]->xfrm_vec[i];
+		}
+		xfrm_nr = ti;
+		if (npols > 1) {
+			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family, net);
+			tpp = stp;
+		}
+
+		/* For each tunnel xfrm, find the first matching tmpl.
+		 * For each tmpl before that, find corresponding xfrm.
+		 * Order is _important_. Later we will implement
+		 * some barriers, but at the moment barriers
+		 * are implied between each two transformations.
+		 */
+		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
+			k = xfrm_policy_ok(tpp[i], sp, k, family);
+			if (k < 0) {
+				if (k < -1)
+					/* "-2 - errored_index" returned */
+					xerr_idx = -(2+k);
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
+				goto reject;
+			}
+		}
+
+		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
+			goto reject;
+		}
+
+		xfrm_pols_put(pols, npols);
+		return 1;
+	}
+	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
+
+reject:
+	xfrm_secpath_reject(xerr_idx, skb, &fl);
+reject_error:
+	xfrm_pols_put(pols, npols);
+	return 0;
+}
+EXPORT_SYMBOL(__xfrm_policy_check);
+
+int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
+{
+	struct net *net = dev_net(skb->dev);
+	struct flowi fl;
+	struct dst_entry *dst;
+	int res = 1;
+
+	if (xfrm_decode_session(skb, &fl, family) < 0) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
+		return 0;
+	}
+
+	skb_dst_force(skb);
+
+	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
+	if (IS_ERR(dst)) {
+		res = 0;
+		dst = NULL;
+	}
+	skb_dst_set(skb, dst);
+	return res;
+}
+EXPORT_SYMBOL(__xfrm_route_forward);
+
+/* Optimize later using cookies and generation ids. */
+
+static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
+{
+	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
+	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
+	 * get validated by dst_ops->check on every use.  We do this
+	 * because when a normal route referenced by an XFRM dst is
+	 * obsoleted we do not go looking around for all parent
+	 * referencing XFRM dsts so that we can invalidate them.  It
+	 * is just too much work.  Instead we make the checks here on
+	 * every use.  For example:
+	 *
+	 *	XFRM dst A --> IPv4 dst X
+	 *
+	 * X is the "xdst->route" of A (X is also the "dst->path" of A
+	 * in this example).  If X is marked obsolete, "A" will not
+	 * notice.  That's what we are validating here via the
+	 * stale_bundle() check.
+	 *
+	 * When a policy's bundle is pruned, we dst_free() the XFRM
+	 * dst which causes it's ->obsolete field to be set to
+	 * DST_OBSOLETE_DEAD.  If an XFRM dst has been pruned like
+	 * this, we want to force a new route lookup.
+	 */
+	if (dst->obsolete < 0 && !stale_bundle(dst))
+		return dst;
+
+	return NULL;
+}
+
+static int stale_bundle(struct dst_entry *dst)
+{
+	return !xfrm_bundle_ok((struct xfrm_dst *)dst);
+}
+
+void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
+{
+	while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
+		dst->dev = dev_net(dev)->loopback_dev;
+		dev_hold(dst->dev);
+		dev_put(dev);
+	}
+}
+EXPORT_SYMBOL(xfrm_dst_ifdown);
+
+static void xfrm_link_failure(struct sk_buff *skb)
+{
+	/* Impossible. Such dst must be popped before reaches point of failure. */
+}
+
+static struct dst_entry *xfrm_negative_advice(struct dst_entry *dst)
+{
+	if (dst) {
+		if (dst->obsolete) {
+			dst_release(dst);
+			dst = NULL;
+		}
+	}
+	return dst;
+}
+
+void xfrm_garbage_collect(struct net *net)
+{
+	flow_cache_flush(net);
+}
+EXPORT_SYMBOL(xfrm_garbage_collect);
+
+static void xfrm_garbage_collect_deferred(struct net *net)
+{
+	flow_cache_flush_deferred(net);
+}
+
+static void xfrm_init_pmtu(struct dst_entry *dst)
+{
+	do {
+		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+		u32 pmtu, route_mtu_cached;
+
+		pmtu = dst_mtu(dst->child);
+		xdst->child_mtu_cached = pmtu;
+
+		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
+
+		route_mtu_cached = dst_mtu(xdst->route);
+		xdst->route_mtu_cached = route_mtu_cached;
+
+		if (pmtu > route_mtu_cached)
+			pmtu = route_mtu_cached;
+
+		dst_metric_set(dst, RTAX_MTU, pmtu);
+	} while ((dst = dst->next));
+}
+
+/* Check that the bundle accepts the flow and its components are
+ * still valid.
+ */
+
+static int xfrm_bundle_ok(struct xfrm_dst *first)
+{
+	struct dst_entry *dst = &first->u.dst;
+	struct xfrm_dst *last;
+	u32 mtu;
+
+	if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
+	    (dst->dev && !netif_running(dst->dev)))
+		return 0;
+
+	if (dst->flags & DST_XFRM_QUEUE)
+		return 1;
+
+	last = NULL;
+
+	do {
+		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+
+		if (dst->xfrm->km.state != XFRM_STATE_VALID)
+			return 0;
+		if (xdst->xfrm_genid != dst->xfrm->genid)
+			return 0;
+		if (xdst->num_pols > 0 &&
+		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
+			return 0;
+
+		mtu = dst_mtu(dst->child);
+		if (xdst->child_mtu_cached != mtu) {
+			last = xdst;
+			xdst->child_mtu_cached = mtu;
+		}
+
+		if (!dst_check(xdst->route, xdst->route_cookie))
+			return 0;
+		mtu = dst_mtu(xdst->route);
+		if (xdst->route_mtu_cached != mtu) {
+			last = xdst;
+			xdst->route_mtu_cached = mtu;
+		}
+
+		dst = dst->child;
+	} while (dst->xfrm);
+
+	if (likely(!last))
+		return 1;
+
+	mtu = last->child_mtu_cached;
+	for (;;) {
+		dst = &last->u.dst;
+
+		mtu = xfrm_state_mtu(dst->xfrm, mtu);
+		if (mtu > last->route_mtu_cached)
+			mtu = last->route_mtu_cached;
+		dst_metric_set(dst, RTAX_MTU, mtu);
+
+		if (last == first)
+			break;
+
+		last = (struct xfrm_dst *)last->u.dst.next;
+		last->child_mtu_cached = mtu;
+	}
+
+	return 1;
+}
+
+static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
+{
+	return dst_metric_advmss(dst->path);
+}
+
+static unsigned int xfrm_mtu(const struct dst_entry *dst)
+{
+	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
+
+	return mtu ? : dst_mtu(dst->path);
+}
+
+static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
+					   struct sk_buff *skb,
+					   const void *daddr)
+{
+	return dst->path->ops->neigh_lookup(dst, skb, daddr);
+}
+
+int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
+{
+	struct net *net;
+	int err = 0;
+	if (unlikely(afinfo == NULL))
+		return -EINVAL;
+	if (unlikely(afinfo->family >= NPROTO))
+		return -EAFNOSUPPORT;
+	spin_lock(&xfrm_policy_afinfo_lock);
+	if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
+		err = -ENOBUFS;
+	else {
+		struct dst_ops *dst_ops = afinfo->dst_ops;
+		if (likely(dst_ops->kmem_cachep == NULL))
+			dst_ops->kmem_cachep = xfrm_dst_cache;
+		if (likely(dst_ops->check == NULL))
+			dst_ops->check = xfrm_dst_check;
+		if (likely(dst_ops->default_advmss == NULL))
+			dst_ops->default_advmss = xfrm_default_advmss;
+		if (likely(dst_ops->mtu == NULL))
+			dst_ops->mtu = xfrm_mtu;
+		if (likely(dst_ops->negative_advice == NULL))
+			dst_ops->negative_advice = xfrm_negative_advice;
+		if (likely(dst_ops->link_failure == NULL))
+			dst_ops->link_failure = xfrm_link_failure;
+		if (likely(dst_ops->neigh_lookup == NULL))
+			dst_ops->neigh_lookup = xfrm_neigh_lookup;
+		if (likely(afinfo->garbage_collect == NULL))
+			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
+		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
+	}
+	spin_unlock(&xfrm_policy_afinfo_lock);
+
+	rtnl_lock();
+	for_each_net(net) {
+		struct dst_ops *xfrm_dst_ops;
+
+		switch (afinfo->family) {
+		case AF_INET:
+			xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
+			break;
+#if IS_ENABLED(CONFIG_IPV6)
+		case AF_INET6:
+			xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
+			break;
+#endif
+		default:
+			BUG();
+		}
+		*xfrm_dst_ops = *afinfo->dst_ops;
+	}
+	rtnl_unlock();
+
+	return err;
+}
+EXPORT_SYMBOL(xfrm_policy_register_afinfo);
+
+int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
+{
+	int err = 0;
+	if (unlikely(afinfo == NULL))
+		return -EINVAL;
+	if (unlikely(afinfo->family >= NPROTO))
+		return -EAFNOSUPPORT;
+	spin_lock(&xfrm_policy_afinfo_lock);
+	if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
+		if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
+			err = -EINVAL;
+		else
+			RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
+					 NULL);
+	}
+	spin_unlock(&xfrm_policy_afinfo_lock);
+	if (!err) {
+		struct dst_ops *dst_ops = afinfo->dst_ops;
+
+		synchronize_rcu();
+
+		dst_ops->kmem_cachep = NULL;
+		dst_ops->check = NULL;
+		dst_ops->negative_advice = NULL;
+		dst_ops->link_failure = NULL;
+		afinfo->garbage_collect = NULL;
+	}
+	return err;
+}
+EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
+
+static void __net_init xfrm_dst_ops_init(struct net *net)
+{
+	struct xfrm_policy_afinfo *afinfo;
+
+	rcu_read_lock();
+	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]);
+	if (afinfo)
+		net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
+#if IS_ENABLED(CONFIG_IPV6)
+	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]);
+	if (afinfo)
+		net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
+#endif
+	rcu_read_unlock();
+}
+
+static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+	switch (event) {
+	case NETDEV_DOWN:
+		xfrm_garbage_collect(dev_net(dev));
+	}
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block xfrm_dev_notifier = {
+	.notifier_call	= xfrm_dev_event,
+};
+
+#ifdef CONFIG_XFRM_STATISTICS
+static int __net_init xfrm_statistics_init(struct net *net)
+{
+	int rv;
+	net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
+	if (!net->mib.xfrm_statistics)
+		return -ENOMEM;
+	rv = xfrm_proc_init(net);
+	if (rv < 0)
+		free_percpu(net->mib.xfrm_statistics);
+	return rv;
+}
+
+static void xfrm_statistics_fini(struct net *net)
+{
+	xfrm_proc_fini(net);
+	free_percpu(net->mib.xfrm_statistics);
+}
+#else
+static int __net_init xfrm_statistics_init(struct net *net)
+{
+	return 0;
+}
+
+static void xfrm_statistics_fini(struct net *net)
+{
+}
+#endif
+
+static int __net_init xfrm_policy_init(struct net *net)
+{
+	unsigned int hmask, sz;
+	int dir;
+
+	if (net_eq(net, &init_net))
+		xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
+					   sizeof(struct xfrm_dst),
+					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
+					   NULL);
+
+	hmask = 8 - 1;
+	sz = (hmask+1) * sizeof(struct hlist_head);
+
+	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
+	if (!net->xfrm.policy_byidx)
+		goto out_byidx;
+	net->xfrm.policy_idx_hmask = hmask;
+
+	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
+		struct xfrm_policy_hash *htab;
+
+		net->xfrm.policy_count[dir] = 0;
+		net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
+		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
+
+		htab = &net->xfrm.policy_bydst[dir];
+		htab->table = xfrm_hash_alloc(sz);
+		if (!htab->table)
+			goto out_bydst;
+		htab->hmask = hmask;
+		htab->dbits4 = 32;
+		htab->sbits4 = 32;
+		htab->dbits6 = 128;
+		htab->sbits6 = 128;
+	}
+	net->xfrm.policy_hthresh.lbits4 = 32;
+	net->xfrm.policy_hthresh.rbits4 = 32;
+	net->xfrm.policy_hthresh.lbits6 = 128;
+	net->xfrm.policy_hthresh.rbits6 = 128;
+
+	seqlock_init(&net->xfrm.policy_hthresh.lock);
+
+	INIT_LIST_HEAD(&net->xfrm.policy_all);
+	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
+	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
+	if (net_eq(net, &init_net))
+		register_netdevice_notifier(&xfrm_dev_notifier);
+	return 0;
+
+out_bydst:
+	for (dir--; dir >= 0; dir--) {
+		struct xfrm_policy_hash *htab;
+
+		htab = &net->xfrm.policy_bydst[dir];
+		xfrm_hash_free(htab->table, sz);
+	}
+	xfrm_hash_free(net->xfrm.policy_byidx, sz);
+out_byidx:
+	return -ENOMEM;
+}
+
+static void xfrm_policy_fini(struct net *net)
+{
+	unsigned int sz;
+	int dir;
+
+	flush_work(&net->xfrm.policy_hash_work);
+#ifdef CONFIG_XFRM_SUB_POLICY
+	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
+#endif
+	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
+
+	WARN_ON(!list_empty(&net->xfrm.policy_all));
+
+	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
+		struct xfrm_policy_hash *htab;
+
+		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
+
+		htab = &net->xfrm.policy_bydst[dir];
+		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
+		WARN_ON(!hlist_empty(htab->table));
+		xfrm_hash_free(htab->table, sz);
+	}
+
+	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
+	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
+	xfrm_hash_free(net->xfrm.policy_byidx, sz);
+}
+
+static int __net_init xfrm_net_init(struct net *net)
+{
+	int rv;
+
+	rv = xfrm_statistics_init(net);
+	if (rv < 0)
+		goto out_statistics;
+	rv = xfrm_state_init(net);
+	if (rv < 0)
+		goto out_state;
+	rv = xfrm_policy_init(net);
+	if (rv < 0)
+		goto out_policy;
+	xfrm_dst_ops_init(net);
+	rv = xfrm_sysctl_init(net);
+	if (rv < 0)
+		goto out_sysctl;
+	rv = flow_cache_init(net);
+	if (rv < 0)
+		goto out;
+
+	/* Initialize the per-net locks here */
+	spin_lock_init(&net->xfrm.xfrm_state_lock);
+	rwlock_init(&net->xfrm.xfrm_policy_lock);
+	mutex_init(&net->xfrm.xfrm_cfg_mutex);
+
+	return 0;
+
+out:
+	xfrm_sysctl_fini(net);
+out_sysctl:
+	xfrm_policy_fini(net);
+out_policy:
+	xfrm_state_fini(net);
+out_state:
+	xfrm_statistics_fini(net);
+out_statistics:
+	return rv;
+}
+
+static void __net_exit xfrm_net_exit(struct net *net)
+{
+	flow_cache_fini(net);
+	xfrm_sysctl_fini(net);
+	xfrm_policy_fini(net);
+	xfrm_state_fini(net);
+	xfrm_statistics_fini(net);
+}
+
+static struct pernet_operations __net_initdata xfrm_net_ops = {
+	.init = xfrm_net_init,
+	.exit = xfrm_net_exit,
+};
+
+void __init xfrm_init(void)
+{
+	register_pernet_subsys(&xfrm_net_ops);
+	xfrm_input_init();
+}
+
+#ifdef CONFIG_AUDITSYSCALL
+static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
+					 struct audit_buffer *audit_buf)
+{
+	struct xfrm_sec_ctx *ctx = xp->security;
+	struct xfrm_selector *sel = &xp->selector;
+
+	if (ctx)
+		audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
+				 ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
+
+	switch (sel->family) {
+	case AF_INET:
+		audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
+		if (sel->prefixlen_s != 32)
+			audit_log_format(audit_buf, " src_prefixlen=%d",
+					 sel->prefixlen_s);
+		audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
+		if (sel->prefixlen_d != 32)
+			audit_log_format(audit_buf, " dst_prefixlen=%d",
+					 sel->prefixlen_d);
+		break;
+	case AF_INET6:
+		audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
+		if (sel->prefixlen_s != 128)
+			audit_log_format(audit_buf, " src_prefixlen=%d",
+					 sel->prefixlen_s);
+		audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
+		if (sel->prefixlen_d != 128)
+			audit_log_format(audit_buf, " dst_prefixlen=%d",
+					 sel->prefixlen_d);
+		break;
+	}
+}
+
+void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
+{
+	struct audit_buffer *audit_buf;
+
+	audit_buf = xfrm_audit_start("SPD-add");
+	if (audit_buf == NULL)
+		return;
+	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
+	audit_log_format(audit_buf, " res=%u", result);
+	xfrm_audit_common_policyinfo(xp, audit_buf);
+	audit_log_end(audit_buf);
+}
+EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
+
+void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
+			      bool task_valid)
+{
+	struct audit_buffer *audit_buf;
+
+	audit_buf = xfrm_audit_start("SPD-delete");
+	if (audit_buf == NULL)
+		return;
+	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
+	audit_log_format(audit_buf, " res=%u", result);
+	xfrm_audit_common_policyinfo(xp, audit_buf);
+	audit_log_end(audit_buf);
+}
+EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
+#endif
+
+#ifdef CONFIG_XFRM_MIGRATE
+static bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
+					const struct xfrm_selector *sel_tgt)
+{
+	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
+		if (sel_tgt->family == sel_cmp->family &&
+		    xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr,
+				    sel_cmp->family) &&
+		    xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr,
+				    sel_cmp->family) &&
+		    sel_tgt->prefixlen_d == sel_cmp->prefixlen_d &&
+		    sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) {
+			return true;
+		}
+	} else {
+		if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) {
+			return true;
+		}
+	}
+	return false;
+}
+
+static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
+						    u8 dir, u8 type, struct net *net)
+{
+	struct xfrm_policy *pol, *ret = NULL;
+	struct hlist_head *chain;
+	u32 priority = ~0U;
+
+	read_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME*/
+	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
+	hlist_for_each_entry(pol, chain, bydst) {
+		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
+		    pol->type == type) {
+			ret = pol;
+			priority = ret->priority;
+			break;
+		}
+	}
+	chain = &net->xfrm.policy_inexact[dir];
+	hlist_for_each_entry(pol, chain, bydst) {
+		if (xfrm_migrate_selector_match(sel, &pol->selector) &&
+		    pol->type == type &&
+		    pol->priority < priority) {
+			ret = pol;
+			break;
+		}
+	}
+
+	if (ret)
+		xfrm_pol_hold(ret);
+
+	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+	return ret;
+}
+
+static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
+{
+	int match = 0;
+
+	if (t->mode == m->mode && t->id.proto == m->proto &&
+	    (m->reqid == 0 || t->reqid == m->reqid)) {
+		switch (t->mode) {
+		case XFRM_MODE_TUNNEL:
+		case XFRM_MODE_BEET:
+			if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
+					    m->old_family) &&
+			    xfrm_addr_equal(&t->saddr, &m->old_saddr,
+					    m->old_family)) {
+				match = 1;
+			}
+			break;
+		case XFRM_MODE_TRANSPORT:
+			/* in case of transport mode, template does not store
+			   any IP addresses, hence we just compare mode and
+			   protocol */
+			match = 1;
+			break;
+		default:
+			break;
+		}
+	}
+	return match;
+}
+
+/* update endpoint address(es) of template(s) */
+static int xfrm_policy_migrate(struct xfrm_policy *pol,
+			       struct xfrm_migrate *m, int num_migrate)
+{
+	struct xfrm_migrate *mp;
+	int i, j, n = 0;
+
+	write_lock_bh(&pol->lock);
+	if (unlikely(pol->walk.dead)) {
+		/* target policy has been deleted */
+		write_unlock_bh(&pol->lock);
+		return -ENOENT;
+	}
+
+	for (i = 0; i < pol->xfrm_nr; i++) {
+		for (j = 0, mp = m; j < num_migrate; j++, mp++) {
+			if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
+				continue;
+			n++;
+			if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
+			    pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
+				continue;
+			/* update endpoints */
+			memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
+			       sizeof(pol->xfrm_vec[i].id.daddr));
+			memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
+			       sizeof(pol->xfrm_vec[i].saddr));
+			pol->xfrm_vec[i].encap_family = mp->new_family;
+			/* flush bundles */
+			atomic_inc(&pol->genid);
+		}
+	}
+
+	write_unlock_bh(&pol->lock);
+
+	if (!n)
+		return -ENODATA;
+
+	return 0;
+}
+
+static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
+{
+	int i, j;
+
+	if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH)
+		return -EINVAL;
+
+	for (i = 0; i < num_migrate; i++) {
+		if (xfrm_addr_equal(&m[i].old_daddr, &m[i].new_daddr,
+				    m[i].old_family) &&
+		    xfrm_addr_equal(&m[i].old_saddr, &m[i].new_saddr,
+				    m[i].old_family))
+			return -EINVAL;
+		if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
+		    xfrm_addr_any(&m[i].new_saddr, m[i].new_family))
+			return -EINVAL;
+
+		/* check if there is any duplicated entry */
+		for (j = i + 1; j < num_migrate; j++) {
+			if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
+				    sizeof(m[i].old_daddr)) &&
+			    !memcmp(&m[i].old_saddr, &m[j].old_saddr,
+				    sizeof(m[i].old_saddr)) &&
+			    m[i].proto == m[j].proto &&
+			    m[i].mode == m[j].mode &&
+			    m[i].reqid == m[j].reqid &&
+			    m[i].old_family == m[j].old_family)
+				return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
+		 struct xfrm_migrate *m, int num_migrate,
+		 struct xfrm_kmaddress *k, struct net *net)
+{
+	int i, err, nx_cur = 0, nx_new = 0;
+	struct xfrm_policy *pol = NULL;
+	struct xfrm_state *x, *xc;
+	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
+	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
+	struct xfrm_migrate *mp;
+
+	if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
+		goto out;
+
+	/* Stage 1 - find policy */
+	if ((pol = xfrm_migrate_policy_find(sel, dir, type, net)) == NULL) {
+		err = -ENOENT;
+		goto out;
+	}
+
+	/* Stage 2 - find and update state(s) */
+	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
+		if ((x = xfrm_migrate_state_find(mp, net))) {
+			x_cur[nx_cur] = x;
+			nx_cur++;
+			if ((xc = xfrm_state_migrate(x, mp))) {
+				x_new[nx_new] = xc;
+				nx_new++;
+			} else {
+				err = -ENODATA;
+				goto restore_state;
+			}
+		}
+	}
+
+	/* Stage 3 - update policy */
+	if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
+		goto restore_state;
+
+	/* Stage 4 - delete old state(s) */
+	if (nx_cur) {
+		xfrm_states_put(x_cur, nx_cur);
+		xfrm_states_delete(x_cur, nx_cur);
+	}
+
+	/* Stage 5 - announce */
+	km_migrate(sel, dir, type, m, num_migrate, k);
+
+	xfrm_pol_put(pol);
+
+	return 0;
+out:
+	return err;
+
+restore_state:
+	if (pol)
+		xfrm_pol_put(pol);
+	if (nx_cur)
+		xfrm_states_put(x_cur, nx_cur);
+	if (nx_new)
+		xfrm_states_delete(x_new, nx_new);
+
+	return err;
+}
+EXPORT_SYMBOL(xfrm_migrate);
+#endif