[linux-2.6-block.git] / net / bridge / br_nf_core.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	Handle firewalling core
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *	Bart De Schuymer		<bdschuym@pandora.be>
 *
 *	Lennert dedicates this file to Kerstin Wurdinger.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/in_route.h>
#include <linux/inetdevice.h>
#include <net/route.h>

#include "br_private.h"
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif

static void fake_update_pmtu(struct dst_entry *dst, struct sock *sk,
			     struct sk_buff *skb, u32 mtu)
{
}

static void fake_redirect(struct dst_entry *dst, struct sock *sk,
			  struct sk_buff *skb)
{
}

static u32 *fake_cow_metrics(struct dst_entry *dst, unsigned long old)
{
	return NULL;
}

static struct neighbour *fake_neigh_lookup(const struct dst_entry *dst,
					   struct sk_buff *skb,
					   const void *daddr)
{
	return NULL;
}

static unsigned int fake_mtu(const struct dst_entry *dst)
{
	return dst->dev->mtu;
}

static struct dst_ops fake_dst_ops = {
	.family		= AF_INET,
	.update_pmtu	= fake_update_pmtu,
	.redirect	= fake_redirect,
	.cow_metrics	= fake_cow_metrics,
	.neigh_lookup	= fake_neigh_lookup,
	.mtu		= fake_mtu,
};

/*
 * Initialize bogus route table used to keep netfilter happy.
 * Currently, we fill in the PMTU entry because netfilter
 * refragmentation needs it, and the rt_flags entry because
 * ipt_REJECT needs it.  Future netfilter modules might
 * require us to fill additional fields.
 */
static const u32 br_dst_default_metrics[RTAX_MAX] = {
	[RTAX_MTU - 1] = 1500,
};

void br_netfilter_rtable_init(struct net_bridge *br)
{
	struct rtable *rt = &br->fake_rtable;

	atomic_set(&rt->dst.__refcnt, 1);
	rt->dst.dev = br->dev;
	dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
	rt->dst.flags	= DST_NOXFRM | DST_FAKE_RTABLE;
	rt->dst.ops = &fake_dst_ops;
}

int __init br_nf_core_init(void)
{
	return dst_entries_init(&fake_dst_ops);
}

void br_nf_core_fini(void)
{
	dst_entries_destroy(&fake_dst_ops);
}
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
34666d46 PNA	2	/*
	3	* Handle firewalling core
	4	* Linux ethernet bridge
	5	*
	6	* Authors:
	7	* Lennert Buytenhek <buytenh@gnu.org>
	8	* Bart De Schuymer <bdschuym@pandora.be>
	9	*
34666d46 PNA	10	* Lennert dedicates this file to Kerstin Wurdinger.
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/kernel.h>
	15	#include <linux/in_route.h>
	16	#include <linux/inetdevice.h>
	17	#include <net/route.h>
	18
	19	#include "br_private.h"
	20	#ifdef CONFIG_SYSCTL
	21	#include <linux/sysctl.h>
	22	#endif
	23
	24	static void fake_update_pmtu(struct dst_entry dst, struct sock sk,
	25	struct sk_buff *skb, u32 mtu)
	26	{
	27	}
	28
	29	static void fake_redirect(struct dst_entry dst, struct sock sk,
	30	struct sk_buff *skb)
	31	{
	32	}
	33
	34	static u32 fake_cow_metrics(struct dst_entry dst, unsigned long old)
	35	{
	36	return NULL;
	37	}
	38
	39	static struct neighbour fake_neigh_lookup(const struct dst_entry dst,
	40	struct sk_buff *skb,
	41	const void *daddr)
	42	{
	43	return NULL;
	44	}
	45
	46	static unsigned int fake_mtu(const struct dst_entry *dst)
	47	{
	48	return dst->dev->mtu;
	49	}
	50
	51	static struct dst_ops fake_dst_ops = {
	52	.family = AF_INET,
34666d46 PNA	53	.update_pmtu = fake_update_pmtu,
	54	.redirect = fake_redirect,
	55	.cow_metrics = fake_cow_metrics,
	56	.neigh_lookup = fake_neigh_lookup,
	57	.mtu = fake_mtu,
	58	};
	59
	60	/*
	61	* Initialize bogus route table used to keep netfilter happy.
	62	* Currently, we fill in the PMTU entry because netfilter
	63	* refragmentation needs it, and the rt_flags entry because
	64	* ipt_REJECT needs it. Future netfilter modules might
	65	* require us to fill additional fields.
	66	*/
	67	static const u32 br_dst_default_metrics[RTAX_MAX] = {
	68	[RTAX_MTU - 1] = 1500,
	69	};
	70
	71	void br_netfilter_rtable_init(struct net_bridge *br)
	72	{
	73	struct rtable *rt = &br->fake_rtable;
	74
	75	atomic_set(&rt->dst.__refcnt, 1);
	76	rt->dst.dev = br->dev;
34666d46 PNA	77	dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
	78	rt->dst.flags = DST_NOXFRM \| DST_FAKE_RTABLE;
	79	rt->dst.ops = &fake_dst_ops;
	80	}
	81
	82	int __init br_nf_core_init(void)
	83	{
	84	return dst_entries_init(&fake_dst_ops);
	85	}
	86
	87	void br_nf_core_fini(void)
	88	{
	89	dst_entries_destroy(&fake_dst_ops);
	90	}