Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 920 insertions, 0 deletions

diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c
new file mode 100644
index 000000000..bac353bea
--- /dev/null
+++ b/net/sched/act_ife.c
@@ -0,0 +1,920 @@
+/*
+ * net/sched/ife.c	Inter-FE action based on ForCES WG InterFE LFB
+ *
+ *		Refer to:
+ *		draft-ietf-forces-interfelfb-03
+ *		and
+ *		netdev01 paper:
+ *		"Distributing Linux Traffic Control Classifier-Action
+ *		Subsystem"
+ *		Authors: Jamal Hadi Salim and Damascene M. Joachimpillai
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * copyright Jamal Hadi Salim (2015)
+ *
+*/
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <net/net_namespace.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <uapi/linux/tc_act/tc_ife.h>
+#include <net/tc_act/tc_ife.h>
+#include <linux/etherdevice.h>
+#include <net/ife.h>
+
+static unsigned int ife_net_id;
+static int max_metacnt = IFE_META_MAX + 1;
+static struct tc_action_ops act_ife_ops;
+
+static const struct nla_policy ife_policy[TCA_IFE_MAX + 1] = {
+	[TCA_IFE_PARMS] = { .len = sizeof(struct tc_ife)},
+	[TCA_IFE_DMAC] = { .len = ETH_ALEN},
+	[TCA_IFE_SMAC] = { .len = ETH_ALEN},
+	[TCA_IFE_TYPE] = { .type = NLA_U16},
+};
+
+int ife_encode_meta_u16(u16 metaval, void *skbdata, struct tcf_meta_info *mi)
+{
+	u16 edata = 0;
+
+	if (mi->metaval)
+		edata = *(u16 *)mi->metaval;
+	else if (metaval)
+		edata = metaval;
+
+	if (!edata) /* will not encode */
+		return 0;
+
+	edata = htons(edata);
+	return ife_tlv_meta_encode(skbdata, mi->metaid, 2, &edata);
+}
+EXPORT_SYMBOL_GPL(ife_encode_meta_u16);
+
+int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi)
+{
+	if (mi->metaval)
+		return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval);
+	else
+		return nla_put(skb, mi->metaid, 0, NULL);
+}
+EXPORT_SYMBOL_GPL(ife_get_meta_u32);
+
+int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi)
+{
+	if (metaval || mi->metaval)
+		return 8; /* T+L+V == 2+2+4 */
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ife_check_meta_u32);
+
+int ife_check_meta_u16(u16 metaval, struct tcf_meta_info *mi)
+{
+	if (metaval || mi->metaval)
+		return 8; /* T+L+(V) == 2+2+(2+2bytepad) */
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ife_check_meta_u16);
+
+int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi)
+{
+	u32 edata = metaval;
+
+	if (mi->metaval)
+		edata = *(u32 *)mi->metaval;
+	else if (metaval)
+		edata = metaval;
+
+	if (!edata) /* will not encode */
+		return 0;
+
+	edata = htonl(edata);
+	return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata);
+}
+EXPORT_SYMBOL_GPL(ife_encode_meta_u32);
+
+int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi)
+{
+	if (mi->metaval)
+		return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval);
+	else
+		return nla_put(skb, mi->metaid, 0, NULL);
+}
+EXPORT_SYMBOL_GPL(ife_get_meta_u16);
+
+int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp)
+{
+	mi->metaval = kmemdup(metaval, sizeof(u32), gfp);
+	if (!mi->metaval)
+		return -ENOMEM;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ife_alloc_meta_u32);
+
+int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp)
+{
+	mi->metaval = kmemdup(metaval, sizeof(u16), gfp);
+	if (!mi->metaval)
+		return -ENOMEM;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ife_alloc_meta_u16);
+
+void ife_release_meta_gen(struct tcf_meta_info *mi)
+{
+	kfree(mi->metaval);
+}
+EXPORT_SYMBOL_GPL(ife_release_meta_gen);
+
+int ife_validate_meta_u32(void *val, int len)
+{
+	if (len == sizeof(u32))
+		return 0;
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(ife_validate_meta_u32);
+
+int ife_validate_meta_u16(void *val, int len)
+{
+	/* length will not include padding */
+	if (len == sizeof(u16))
+		return 0;
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(ife_validate_meta_u16);
+
+static LIST_HEAD(ifeoplist);
+static DEFINE_RWLOCK(ife_mod_lock);
+
+static struct tcf_meta_ops *find_ife_oplist(u16 metaid)
+{
+	struct tcf_meta_ops *o;
+
+	read_lock(&ife_mod_lock);
+	list_for_each_entry(o, &ifeoplist, list) {
+		if (o->metaid == metaid) {
+			if (!try_module_get(o->owner))
+				o = NULL;
+			read_unlock(&ife_mod_lock);
+			return o;
+		}
+	}
+	read_unlock(&ife_mod_lock);
+
+	return NULL;
+}
+
+int register_ife_op(struct tcf_meta_ops *mops)
+{
+	struct tcf_meta_ops *m;
+
+	if (!mops->metaid || !mops->metatype || !mops->name ||
+	    !mops->check_presence || !mops->encode || !mops->decode ||
+	    !mops->get || !mops->alloc)
+		return -EINVAL;
+
+	write_lock(&ife_mod_lock);
+
+	list_for_each_entry(m, &ifeoplist, list) {
+		if (m->metaid == mops->metaid ||
+		    (strcmp(mops->name, m->name) == 0)) {
+			write_unlock(&ife_mod_lock);
+			return -EEXIST;
+		}
+	}
+
+	if (!mops->release)
+		mops->release = ife_release_meta_gen;
+
+	list_add_tail(&mops->list, &ifeoplist);
+	write_unlock(&ife_mod_lock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(unregister_ife_op);
+
+int unregister_ife_op(struct tcf_meta_ops *mops)
+{
+	struct tcf_meta_ops *m;
+	int err = -ENOENT;
+
+	write_lock(&ife_mod_lock);
+	list_for_each_entry(m, &ifeoplist, list) {
+		if (m->metaid == mops->metaid) {
+			list_del(&mops->list);
+			err = 0;
+			break;
+		}
+	}
+	write_unlock(&ife_mod_lock);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(register_ife_op);
+
+static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len)
+{
+	int ret = 0;
+	/* XXX: unfortunately cant use nla_policy at this point
+	* because a length of 0 is valid in the case of
+	* "allow". "use" semantics do enforce for proper
+	* length and i couldve use nla_policy but it makes it hard
+	* to use it just for that..
+	*/
+	if (ops->validate)
+		return ops->validate(val, len);
+
+	if (ops->metatype == NLA_U32)
+		ret = ife_validate_meta_u32(val, len);
+	else if (ops->metatype == NLA_U16)
+		ret = ife_validate_meta_u16(val, len);
+
+	return ret;
+}
+
+#ifdef CONFIG_MODULES
+static const char *ife_meta_id2name(u32 metaid)
+{
+	switch (metaid) {
+	case IFE_META_SKBMARK:
+		return "skbmark";
+	case IFE_META_PRIO:
+		return "skbprio";
+	case IFE_META_TCINDEX:
+		return "tcindex";
+	default:
+		return "unknown";
+	}
+}
+#endif
+
+/* called when adding new meta information
+*/
+static int load_metaops_and_vet(u32 metaid, void *val, int len, bool rtnl_held)
+{
+	struct tcf_meta_ops *ops = find_ife_oplist(metaid);
+	int ret = 0;
+
+	if (!ops) {
+		ret = -ENOENT;
+#ifdef CONFIG_MODULES
+		if (rtnl_held)
+			rtnl_unlock();
+		request_module("ife-meta-%s", ife_meta_id2name(metaid));
+		if (rtnl_held)
+			rtnl_lock();
+		ops = find_ife_oplist(metaid);
+#endif
+	}
+
+	if (ops) {
+		ret = 0;
+		if (len)
+			ret = ife_validate_metatype(ops, val, len);
+
+		module_put(ops->owner);
+	}
+
+	return ret;
+}
+
+/* called when adding new meta information
+*/
+static int __add_metainfo(const struct tcf_meta_ops *ops,
+			  struct tcf_ife_info *ife, u32 metaid, void *metaval,
+			  int len, bool atomic, bool exists)
+{
+	struct tcf_meta_info *mi = NULL;
+	int ret = 0;
+
+	mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL);
+	if (!mi)
+		return -ENOMEM;
+
+	mi->metaid = metaid;
+	mi->ops = ops;
+	if (len > 0) {
+		ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL);
+		if (ret != 0) {
+			kfree(mi);
+			return ret;
+		}
+	}
+
+	if (exists)
+		spin_lock_bh(&ife->tcf_lock);
+	list_add_tail(&mi->metalist, &ife->metalist);
+	if (exists)
+		spin_unlock_bh(&ife->tcf_lock);
+
+	return ret;
+}
+
+static int add_metainfo_and_get_ops(const struct tcf_meta_ops *ops,
+				    struct tcf_ife_info *ife, u32 metaid,
+				    bool exists)
+{
+	int ret;
+
+	if (!try_module_get(ops->owner))
+		return -ENOENT;
+	ret = __add_metainfo(ops, ife, metaid, NULL, 0, true, exists);
+	if (ret)
+		module_put(ops->owner);
+	return ret;
+}
+
+static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval,
+			int len, bool exists)
+{
+	const struct tcf_meta_ops *ops = find_ife_oplist(metaid);
+	int ret;
+
+	if (!ops)
+		return -ENOENT;
+	ret = __add_metainfo(ops, ife, metaid, metaval, len, false, exists);
+	if (ret)
+		/*put back what find_ife_oplist took */
+		module_put(ops->owner);
+	return ret;
+}
+
+static int use_all_metadata(struct tcf_ife_info *ife, bool exists)
+{
+	struct tcf_meta_ops *o;
+	int rc = 0;
+	int installed = 0;
+
+	read_lock(&ife_mod_lock);
+	list_for_each_entry(o, &ifeoplist, list) {
+		rc = add_metainfo_and_get_ops(o, ife, o->metaid, exists);
+		if (rc == 0)
+			installed += 1;
+	}
+	read_unlock(&ife_mod_lock);
+
+	if (installed)
+		return 0;
+	else
+		return -EINVAL;
+}
+
+static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife)
+{
+	struct tcf_meta_info *e;
+	struct nlattr *nest;
+	unsigned char *b = skb_tail_pointer(skb);
+	int total_encoded = 0;
+
+	/*can only happen on decode */
+	if (list_empty(&ife->metalist))
+		return 0;
+
+	nest = nla_nest_start(skb, TCA_IFE_METALST);
+	if (!nest)
+		goto out_nlmsg_trim;
+
+	list_for_each_entry(e, &ife->metalist, metalist) {
+		if (!e->ops->get(skb, e))
+			total_encoded += 1;
+	}
+
+	if (!total_encoded)
+		goto out_nlmsg_trim;
+
+	nla_nest_end(skb, nest);
+
+	return 0;
+
+out_nlmsg_trim:
+	nlmsg_trim(skb, b);
+	return -1;
+}
+
+/* under ife->tcf_lock */
+static void _tcf_ife_cleanup(struct tc_action *a)
+{
+	struct tcf_ife_info *ife = to_ife(a);
+	struct tcf_meta_info *e, *n;
+
+	list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
+		list_del(&e->metalist);
+		if (e->metaval) {
+			if (e->ops->release)
+				e->ops->release(e);
+			else
+				kfree(e->metaval);
+		}
+		module_put(e->ops->owner);
+		kfree(e);
+	}
+}
+
+static void tcf_ife_cleanup(struct tc_action *a)
+{
+	struct tcf_ife_info *ife = to_ife(a);
+	struct tcf_ife_params *p;
+
+	spin_lock_bh(&ife->tcf_lock);
+	_tcf_ife_cleanup(a);
+	spin_unlock_bh(&ife->tcf_lock);
+
+	p = rcu_dereference_protected(ife->params, 1);
+	if (p)
+		kfree_rcu(p, rcu);
+}
+
+static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb,
+			     bool exists, bool rtnl_held)
+{
+	int len = 0;
+	int rc = 0;
+	int i = 0;
+	void *val;
+
+	for (i = 1; i < max_metacnt; i++) {
+		if (tb[i]) {
+			val = nla_data(tb[i]);
+			len = nla_len(tb[i]);
+
+			rc = load_metaops_and_vet(i, val, len, rtnl_held);
+			if (rc != 0)
+				return rc;
+
+			rc = add_metainfo(ife, i, val, len, exists);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return rc;
+}
+
+static int tcf_ife_init(struct net *net, struct nlattr *nla,
+			struct nlattr *est, struct tc_action **a,
+			int ovr, int bind, bool rtnl_held,
+			struct netlink_ext_ack *extack)
+{
+	struct tc_action_net *tn = net_generic(net, ife_net_id);
+	struct nlattr *tb[TCA_IFE_MAX + 1];
+	struct nlattr *tb2[IFE_META_MAX + 1];
+	struct tcf_ife_params *p;
+	struct tcf_ife_info *ife;
+	u16 ife_type = ETH_P_IFE;
+	struct tc_ife *parm;
+	u8 *daddr = NULL;
+	u8 *saddr = NULL;
+	bool exists = false;
+	int ret = 0;
+	u32 index;
+	int err;
+
+	if (!nla) {
+		NL_SET_ERR_MSG_MOD(extack, "IFE requires attributes to be passed");
+		return -EINVAL;
+	}
+
+	err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy, NULL);
+	if (err < 0)
+		return err;
+
+	if (!tb[TCA_IFE_PARMS])
+		return -EINVAL;
+
+	parm = nla_data(tb[TCA_IFE_PARMS]);
+
+	/* IFE_DECODE is 0 and indicates the opposite of IFE_ENCODE because
+	 * they cannot run as the same time. Check on all other values which
+	 * are not supported right now.
+	 */
+	if (parm->flags & ~IFE_ENCODE)
+		return -EINVAL;
+
+	p = kzalloc(sizeof(*p), GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+
+	index = parm->index;
+	err = tcf_idr_check_alloc(tn, &index, a, bind);
+	if (err < 0) {
+		kfree(p);
+		return err;
+	}
+	exists = err;
+	if (exists && bind) {
+		kfree(p);
+		return 0;
+	}
+
+	if (!exists) {
+		ret = tcf_idr_create(tn, index, est, a, &act_ife_ops,
+				     bind, true);
+		if (ret) {
+			tcf_idr_cleanup(tn, index);
+			kfree(p);
+			return ret;
+		}
+		ret = ACT_P_CREATED;
+	} else if (!ovr) {
+		tcf_idr_release(*a, bind);
+		kfree(p);
+		return -EEXIST;
+	}
+
+	ife = to_ife(*a);
+	p->flags = parm->flags;
+
+	if (parm->flags & IFE_ENCODE) {
+		if (tb[TCA_IFE_TYPE])
+			ife_type = nla_get_u16(tb[TCA_IFE_TYPE]);
+		if (tb[TCA_IFE_DMAC])
+			daddr = nla_data(tb[TCA_IFE_DMAC]);
+		if (tb[TCA_IFE_SMAC])
+			saddr = nla_data(tb[TCA_IFE_SMAC]);
+	}
+
+	if (parm->flags & IFE_ENCODE) {
+		if (daddr)
+			ether_addr_copy(p->eth_dst, daddr);
+		else
+			eth_zero_addr(p->eth_dst);
+
+		if (saddr)
+			ether_addr_copy(p->eth_src, saddr);
+		else
+			eth_zero_addr(p->eth_src);
+
+		p->eth_type = ife_type;
+	}
+
+
+	if (ret == ACT_P_CREATED)
+		INIT_LIST_HEAD(&ife->metalist);
+
+	if (tb[TCA_IFE_METALST]) {
+		err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST],
+				       NULL, NULL);
+		if (err) {
+metadata_parse_err:
+			tcf_idr_release(*a, bind);
+			kfree(p);
+			return err;
+		}
+
+		err = populate_metalist(ife, tb2, exists, rtnl_held);
+		if (err)
+			goto metadata_parse_err;
+
+	} else {
+		/* if no passed metadata allow list or passed allow-all
+		 * then here we process by adding as many supported metadatum
+		 * as we can. You better have at least one else we are
+		 * going to bail out
+		 */
+		err = use_all_metadata(ife, exists);
+		if (err) {
+			tcf_idr_release(*a, bind);
+			kfree(p);
+			return err;
+		}
+	}
+
+	if (exists)
+		spin_lock_bh(&ife->tcf_lock);
+	ife->tcf_action = parm->action;
+	/* protected by tcf_lock when modifying existing action */
+	rcu_swap_protected(ife->params, p, 1);
+
+	if (exists)
+		spin_unlock_bh(&ife->tcf_lock);
+	if (p)
+		kfree_rcu(p, rcu);
+
+	if (ret == ACT_P_CREATED)
+		tcf_idr_insert(tn, *a);
+
+	return ret;
+}
+
+static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind,
+			int ref)
+{
+	unsigned char *b = skb_tail_pointer(skb);
+	struct tcf_ife_info *ife = to_ife(a);
+	struct tcf_ife_params *p;
+	struct tc_ife opt = {
+		.index = ife->tcf_index,
+		.refcnt = refcount_read(&ife->tcf_refcnt) - ref,
+		.bindcnt = atomic_read(&ife->tcf_bindcnt) - bind,
+	};
+	struct tcf_t t;
+
+	spin_lock_bh(&ife->tcf_lock);
+	opt.action = ife->tcf_action;
+	p = rcu_dereference_protected(ife->params,
+				      lockdep_is_held(&ife->tcf_lock));
+	opt.flags = p->flags;
+
+	if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt))
+		goto nla_put_failure;
+
+	tcf_tm_dump(&t, &ife->tcf_tm);
+	if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD))
+		goto nla_put_failure;
+
+	if (!is_zero_ether_addr(p->eth_dst)) {
+		if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, p->eth_dst))
+			goto nla_put_failure;
+	}
+
+	if (!is_zero_ether_addr(p->eth_src)) {
+		if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, p->eth_src))
+			goto nla_put_failure;
+	}
+
+	if (nla_put(skb, TCA_IFE_TYPE, 2, &p->eth_type))
+		goto nla_put_failure;
+
+	if (dump_metalist(skb, ife)) {
+		/*ignore failure to dump metalist */
+		pr_info("Failed to dump metalist\n");
+	}
+
+	spin_unlock_bh(&ife->tcf_lock);
+	return skb->len;
+
+nla_put_failure:
+	spin_unlock_bh(&ife->tcf_lock);
+	nlmsg_trim(skb, b);
+	return -1;
+}
+
+static int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife,
+			      u16 metaid, u16 mlen, void *mdata)
+{
+	struct tcf_meta_info *e;
+
+	/* XXX: use hash to speed up */
+	list_for_each_entry(e, &ife->metalist, metalist) {
+		if (metaid == e->metaid) {
+			if (e->ops) {
+				/* We check for decode presence already */
+				return e->ops->decode(skb, mdata, mlen);
+			}
+		}
+	}
+
+	return -ENOENT;
+}
+
+static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a,
+			  struct tcf_result *res)
+{
+	struct tcf_ife_info *ife = to_ife(a);
+	int action = ife->tcf_action;
+	u8 *ifehdr_end;
+	u8 *tlv_data;
+	u16 metalen;
+
+	bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb);
+	tcf_lastuse_update(&ife->tcf_tm);
+
+	if (skb_at_tc_ingress(skb))
+		skb_push(skb, skb->dev->hard_header_len);
+
+	tlv_data = ife_decode(skb, &metalen);
+	if (unlikely(!tlv_data)) {
+		qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
+		return TC_ACT_SHOT;
+	}
+
+	ifehdr_end = tlv_data + metalen;
+	for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) {
+		u8 *curr_data;
+		u16 mtype;
+		u16 dlen;
+
+		curr_data = ife_tlv_meta_decode(tlv_data, ifehdr_end, &mtype,
+						&dlen, NULL);
+		if (!curr_data) {
+			qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
+			return TC_ACT_SHOT;
+		}
+
+		if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) {
+			/* abuse overlimits to count when we receive metadata
+			 * but dont have an ops for it
+			 */
+			pr_info_ratelimited("Unknown metaid %d dlen %d\n",
+					    mtype, dlen);
+			qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats));
+		}
+	}
+
+	if (WARN_ON(tlv_data != ifehdr_end)) {
+		qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
+		return TC_ACT_SHOT;
+	}
+
+	skb->protocol = eth_type_trans(skb, skb->dev);
+	skb_reset_network_header(skb);
+
+	return action;
+}
+
+/*XXX: check if we can do this at install time instead of current
+ * send data path
+**/
+static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife)
+{
+	struct tcf_meta_info *e, *n;
+	int tot_run_sz = 0, run_sz = 0;
+
+	list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
+		if (e->ops->check_presence) {
+			run_sz = e->ops->check_presence(skb, e);
+			tot_run_sz += run_sz;
+		}
+	}
+
+	return tot_run_sz;
+}
+
+static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a,
+			  struct tcf_result *res, struct tcf_ife_params *p)
+{
+	struct tcf_ife_info *ife = to_ife(a);
+	int action = ife->tcf_action;
+	struct ethhdr *oethh;	/* outer ether header */
+	struct tcf_meta_info *e;
+	/*
+	   OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA
+	   where ORIGDATA = original ethernet header ...
+	 */
+	u16 metalen = ife_get_sz(skb, ife);
+	int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN;
+	unsigned int skboff = 0;
+	int new_len = skb->len + hdrm;
+	bool exceed_mtu = false;
+	void *ife_meta;
+	int err = 0;
+
+	if (!skb_at_tc_ingress(skb)) {
+		if (new_len > skb->dev->mtu)
+			exceed_mtu = true;
+	}
+
+	bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb);
+	tcf_lastuse_update(&ife->tcf_tm);
+
+	if (!metalen) {		/* no metadata to send */
+		/* abuse overlimits to count when we allow packet
+		 * with no metadata
+		 */
+		qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats));
+		return action;
+	}
+	/* could be stupid policy setup or mtu config
+	 * so lets be conservative.. */
+	if ((action == TC_ACT_SHOT) || exceed_mtu) {
+		qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
+		return TC_ACT_SHOT;
+	}
+
+	if (skb_at_tc_ingress(skb))
+		skb_push(skb, skb->dev->hard_header_len);
+
+	ife_meta = ife_encode(skb, metalen);
+
+	spin_lock(&ife->tcf_lock);
+
+	/* XXX: we dont have a clever way of telling encode to
+	 * not repeat some of the computations that are done by
+	 * ops->presence_check...
+	 */
+	list_for_each_entry(e, &ife->metalist, metalist) {
+		if (e->ops->encode) {
+			err = e->ops->encode(skb, (void *)(ife_meta + skboff),
+					     e);
+		}
+		if (err < 0) {
+			/* too corrupt to keep around if overwritten */
+			spin_unlock(&ife->tcf_lock);
+			qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
+			return TC_ACT_SHOT;
+		}
+		skboff += err;
+	}
+	spin_unlock(&ife->tcf_lock);
+	oethh = (struct ethhdr *)skb->data;
+
+	if (!is_zero_ether_addr(p->eth_src))
+		ether_addr_copy(oethh->h_source, p->eth_src);
+	if (!is_zero_ether_addr(p->eth_dst))
+		ether_addr_copy(oethh->h_dest, p->eth_dst);
+	oethh->h_proto = htons(p->eth_type);
+
+	if (skb_at_tc_ingress(skb))
+		skb_pull(skb, skb->dev->hard_header_len);
+
+	return action;
+}
+
+static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a,
+		       struct tcf_result *res)
+{
+	struct tcf_ife_info *ife = to_ife(a);
+	struct tcf_ife_params *p;
+	int ret;
+
+	p = rcu_dereference_bh(ife->params);
+	if (p->flags & IFE_ENCODE) {
+		ret = tcf_ife_encode(skb, a, res, p);
+		return ret;
+	}
+
+	return tcf_ife_decode(skb, a, res);
+}
+
+static int tcf_ife_walker(struct net *net, struct sk_buff *skb,
+			  struct netlink_callback *cb, int type,
+			  const struct tc_action_ops *ops,
+			  struct netlink_ext_ack *extack)
+{
+	struct tc_action_net *tn = net_generic(net, ife_net_id);
+
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
+}
+
+static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index,
+			  struct netlink_ext_ack *extack)
+{
+	struct tc_action_net *tn = net_generic(net, ife_net_id);
+
+	return tcf_idr_search(tn, a, index);
+}
+
+static struct tc_action_ops act_ife_ops = {
+	.kind = "ife",
+	.type = TCA_ACT_IFE,
+	.owner = THIS_MODULE,
+	.act = tcf_ife_act,
+	.dump = tcf_ife_dump,
+	.cleanup = tcf_ife_cleanup,
+	.init = tcf_ife_init,
+	.walk = tcf_ife_walker,
+	.lookup = tcf_ife_search,
+	.size =	sizeof(struct tcf_ife_info),
+};
+
+static __net_init int ife_init_net(struct net *net)
+{
+	struct tc_action_net *tn = net_generic(net, ife_net_id);
+
+	return tc_action_net_init(net, tn, &act_ife_ops);
+}
+
+static void __net_exit ife_exit_net(struct list_head *net_list)
+{
+	tc_action_net_exit(net_list, ife_net_id);
+}
+
+static struct pernet_operations ife_net_ops = {
+	.init = ife_init_net,
+	.exit_batch = ife_exit_net,
+	.id   = &ife_net_id,
+	.size = sizeof(struct tc_action_net),
+};
+
+static int __init ife_init_module(void)
+{
+	return tcf_register_action(&act_ife_ops, &ife_net_ops);
+}
+
+static void __exit ife_cleanup_module(void)
+{
+	tcf_unregister_action(&act_ife_ops, &ife_net_ops);
+}
+
+module_init(ife_init_module);
+module_exit(ife_cleanup_module);
+
+MODULE_AUTHOR("Jamal Hadi Salim(2015)");
+MODULE_DESCRIPTION("Inter-FE LFB action");
+MODULE_LICENSE("GPL");