Commit 0fae2e77 authored by Florian Westphal's avatar Florian Westphal Committed by Patrick McHardy
Browse files

netfilter: af_info: add 'strict' parameter to limit lookup to .oif 



ipv6 fib lookup can set RT6_LOOKUP_F_IFACE flag to restrict search
to an interface, but this flag cannot be set via struct flowi.

Also, it cannot be set via ip6_route_output: this function uses the
passed sock struct to determine if this flag is required
(by testing for nonzero sk_bound_dev_if).

Work around this by passing in an artificial struct sk in case
'strict' argument is true.

This is required to replace the rt6_lookup call in xt_addrtype.c with
nf_afinfo->route().

Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
parent 31ad3dd6

include/linux/netfilter.h

+1 −1
Original line number Diff line number Diff line
@@ -271,7 +271,7 @@ struct nf_afinfo { 
					    unsigned int len,

					    u_int8_t protocol);

	int		(*route)(struct net *net, struct dst_entry **dst,

				 struct flowi *fl);

				 struct flowi *fl, bool strict);

	void		(*saveroute)(const struct sk_buff *skb,

				     struct nf_queue_entry *entry);

	int		(*reroute)(struct sk_buff *skb,

net/ipv4/netfilter.c

+1 −1
Original line number Diff line number Diff line
@@ -222,7 +222,7 @@ static __sum16 nf_ip_checksum_partial(struct sk_buff *skb, unsigned int hook, 
}



static int nf_ip_route(struct net *net, struct dst_entry **dst,

		       struct flowi *fl)

		       struct flowi *fl, bool strict __always_unused)

{

	struct rtable *rt = ip_route_output_key(net, &fl->u.ip4);

	if (IS_ERR(rt))

net/ipv6/netfilter.c

+10 −2
Original line number Diff line number Diff line
@@ -91,9 +91,17 @@ static int nf_ip6_reroute(struct sk_buff *skb, 
}



static int nf_ip6_route(struct net *net, struct dst_entry **dst,

			struct flowi *fl)

			struct flowi *fl, bool strict)

{

	*dst = ip6_route_output(net, NULL, &fl->u.ip6);

	static const struct ipv6_pinfo fake_pinfo;

	static const struct inet_sock fake_sk = {

		/* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */

		.sk.sk_bound_dev_if = 1,

		.pinet6 = (struct ipv6_pinfo *) &fake_pinfo,

	};

	const void *sk = strict ? &fake_sk : NULL;



	*dst = ip6_route_output(net, sk, &fl->u.ip6);

	return (*dst)->error;

}

net/netfilter/nf_conntrack_h323_main.c

+4 −4
Original line number Diff line number Diff line
@@ -732,9 +732,9 @@ static int callforward_do_filter(const union nf_inet_addr *src, 
		memset(&fl2, 0, sizeof(fl2));

		fl2.daddr = dst->ip;

		if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,

				   flowi4_to_flowi(&fl1))) {

				   flowi4_to_flowi(&fl1), false)) {

			if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,

					   flowi4_to_flowi(&fl2))) {

					   flowi4_to_flowi(&fl2), false)) {

				if (rt1->rt_gateway == rt2->rt_gateway &&

				    rt1->dst.dev  == rt2->dst.dev)

					ret = 1;
@@ -756,9 +756,9 @@ static int callforward_do_filter(const union nf_inet_addr *src, 
		memset(&fl2, 0, sizeof(fl2));

		ipv6_addr_copy(&fl2.daddr, &dst->in6);

		if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,

				   flowi6_to_flowi(&fl1))) {

				   flowi6_to_flowi(&fl1), false)) {

			if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,

					   flowi6_to_flowi(&fl2))) {

					   flowi6_to_flowi(&fl2), false)) {

				if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,

					    sizeof(rt1->rt6i_gateway)) &&

				    rt1->dst.dev == rt2->dst.dev)

net/netfilter/xt_TCPMSS.c

+1 −1
Original line number Diff line number Diff line
@@ -166,7 +166,7 @@ static u_int32_t tcpmss_reverse_mtu(const struct sk_buff *skb, 
	rcu_read_lock();

	ai = nf_get_afinfo(family);

	if (ai != NULL)

		ai->route(&init_net, (struct dst_entry **)&rt, &fl);

		ai->route(&init_net, (struct dst_entry **)&rt, &fl, false);

	rcu_read_unlock();



	if (rt != NULL) {

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