Commit a21b06e7 authored by Xin Long's avatar Xin Long Committed by Paolo Abeni
Browse files

net: sched: add helper support in act_ct 



This patch is to add helper support in act_ct for OVS actions=ct(alg=xxx)
offloading, which is corresponding to Commit cae3a262 ("openvswitch:
Allow attaching helpers to ct action") in OVS kernel part.

The difference is when adding TC actions family and proto cannot be got
from the filter/match, other than helper name in tb[TCA_CT_HELPER_NAME],
we also need to send the family in tb[TCA_CT_HELPER_FAMILY] and the
proto in tb[TCA_CT_HELPER_PROTO] to kernel.

Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 19138941

include/net/tc_act/tc_ct.h

+1 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#include <net/netfilter/nf_conntrack_labels.h>



struct tcf_ct_params {

	struct nf_conntrack_helper *helper;

	struct nf_conn *tmpl;

	u16 zone;

include/uapi/linux/tc_act/tc_ct.h

+3 −0
Original line number Diff line number Diff line
@@ -22,6 +22,9 @@ enum { 
	TCA_CT_NAT_PORT_MIN,	/* be16 */

	TCA_CT_NAT_PORT_MAX,	/* be16 */

	TCA_CT_PAD,

	TCA_CT_HELPER_NAME,	/* string */

	TCA_CT_HELPER_FAMILY,	/* u8 */

	TCA_CT_HELPER_PROTO,	/* u8 */

	__TCA_CT_MAX

};

net/sched/act_ct.c

+81 −8
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 
#include <net/netfilter/nf_conntrack_acct.h>

#include <net/netfilter/ipv6/nf_defrag_ipv6.h>

#include <net/netfilter/nf_conntrack_act_ct.h>

#include <net/netfilter/nf_conntrack_seqadj.h>

#include <uapi/linux/netfilter/nf_nat.h>



static struct workqueue_struct *act_ct_wq;
@@ -655,7 +656,7 @@ struct tc_ct_action_net { 


/* Determine whether skb->_nfct is equal to the result of conntrack lookup. */

static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,

				   u16 zone_id, bool force)

				   struct tcf_ct_params *p)

{

	enum ip_conntrack_info ctinfo;

	struct nf_conn *ct;
@@ -665,11 +666,19 @@ static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 
		return false;

	if (!net_eq(net, read_pnet(&ct->ct_net)))

		goto drop_ct;

	if (nf_ct_zone(ct)->id != zone_id)

	if (nf_ct_zone(ct)->id != p->zone)

		goto drop_ct;

	if (p->helper) {

		struct nf_conn_help *help;



		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);

		if (help && rcu_access_pointer(help->helper) != p->helper)

			goto drop_ct;

	}



	/* Force conntrack entry direction. */

	if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {

	if ((p->ct_action & TCA_CT_ACT_FORCE) &&

	    CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {

		if (nf_ct_is_confirmed(ct))

			nf_ct_kill(ct);
@@ -832,6 +841,13 @@ static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 


static void tcf_ct_params_free(struct tcf_ct_params *params)

{

	if (params->helper) {

#if IS_ENABLED(CONFIG_NF_NAT)

		if (params->ct_action & TCA_CT_ACT_NAT)

			nf_nat_helper_put(params->helper);

#endif

		nf_conntrack_helper_put(params->helper);

	}

	if (params->ct_ft)

		tcf_ct_flow_table_put(params->ct_ft);

	if (params->tmpl)
@@ -1026,13 +1042,14 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 
		      struct tcf_result *res)

{

	struct net *net = dev_net(skb->dev);

	bool cached, commit, clear, force;

	enum ip_conntrack_info ctinfo;

	struct tcf_ct *c = to_ct(a);

	struct nf_conn *tmpl = NULL;

	struct nf_hook_state state;

	bool cached, commit, clear;

	int nh_ofs, err, retval;

	struct tcf_ct_params *p;

	bool add_helper = false;

	bool skip_add = false;

	bool defrag = false;

	struct nf_conn *ct;
@@ -1043,7 +1060,6 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 
	retval = READ_ONCE(c->tcf_action);

	commit = p->ct_action & TCA_CT_ACT_COMMIT;

	clear = p->ct_action & TCA_CT_ACT_CLEAR;

	force = p->ct_action & TCA_CT_ACT_FORCE;

	tmpl = p->tmpl;



	tcf_lastuse_update(&c->tcf_tm);
@@ -1086,7 +1102,7 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 
	 * actually run the packet through conntrack twice unless it's for a

	 * different zone.

	 */

	cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);

	cached = tcf_ct_skb_nfct_cached(net, skb, p);

	if (!cached) {

		if (tcf_ct_flow_table_lookup(p, skb, family)) {

			skip_add = true;
@@ -1119,6 +1135,22 @@ static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 
	if (err != NF_ACCEPT)

		goto drop;



	if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {

		err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);

		if (err)

			goto drop;

		add_helper = true;

		if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {

			if (!nfct_seqadj_ext_add(ct))

				goto drop;

		}

	}



	if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {

		if (nf_ct_helper(skb, ct, ctinfo, family) != NF_ACCEPT)

			goto drop;

	}



	if (commit) {

		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);

		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
@@ -1167,6 +1199,9 @@ static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 
	[TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),

	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },

	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },

	[TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },

	[TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },

	[TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },

};



static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
@@ -1256,8 +1291,9 @@ static int tcf_ct_fill_params(struct net *net, 
{

	struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);

	struct nf_conntrack_zone zone;

	int err, family, proto, len;

	struct nf_conn *tmpl;

	int err;

	char *name;



	p->zone = NF_CT_DEFAULT_ZONE_ID;
@@ -1318,10 +1354,31 @@ static int tcf_ct_fill_params(struct net *net, 
		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");

		return -ENOMEM;

	}

	__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);

	p->tmpl = tmpl;

	if (tb[TCA_CT_HELPER_NAME]) {

		name = nla_data(tb[TCA_CT_HELPER_NAME]);

		len = nla_len(tb[TCA_CT_HELPER_NAME]);

		if (len > 16 || name[len - 1] != '\0') {

			NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");

			err = -EINVAL;

			goto err;

		}

		family = tb[TCA_CT_HELPER_FAMILY] ? nla_get_u8(tb[TCA_CT_HELPER_FAMILY]) : AF_INET;

		proto = tb[TCA_CT_HELPER_PROTO] ? nla_get_u8(tb[TCA_CT_HELPER_PROTO]) : IPPROTO_TCP;

		err = nf_ct_add_helper(tmpl, name, family, proto,

				       p->ct_action & TCA_CT_ACT_NAT, &p->helper);

		if (err) {

			NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");

			goto err;

		}

	}



	__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);

	return 0;

err:

	nf_ct_put(p->tmpl);

	p->tmpl = NULL;

	return err;

}



static int tcf_ct_init(struct net *net, struct nlattr *nla,
@@ -1490,6 +1547,19 @@ static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p) 
	return 0;

}



static int tcf_ct_dump_helper(struct sk_buff *skb, struct nf_conntrack_helper *helper)

{

	if (!helper)

		return 0;



	if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||

	    nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||

	    nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))

		return -1;



	return 0;

}



static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,

			      int bind, int ref)

{
@@ -1542,6 +1612,9 @@ static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a, 
	if (tcf_ct_dump_nat(skb, p))

		goto nla_put_failure;



	if (tcf_ct_dump_helper(skb, p->helper))

		goto nla_put_failure;



skip_dump:

	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))

		goto nla_put_failure;