1/*
 2 *	Handle firewalling core
 3 *	Linux ethernet bridge
 4 *
 5 *	Authors:
 6 *	Lennert Buytenhek		<buytenh@gnu.org>
 7 *	Bart De Schuymer		<bdschuym@pandora.be>
 8 *
 9 *	This program is free software; you can redistribute it and/or
10 *	modify it under the terms of the GNU General Public License
11 *	as published by the Free Software Foundation; either version
12 *	2 of the License, or (at your option) any later version.
13 *
14 *	Lennert dedicates this file to Kerstin Wurdinger.
15 */
16
17#include <linux/module.h>
18#include <linux/kernel.h>
19#include <linux/in_route.h>
20#include <linux/inetdevice.h>
21#include <net/route.h>
22
23#include "br_private.h"
24#ifdef CONFIG_SYSCTL
25#include <linux/sysctl.h>
26#endif
27
28static void fake_update_pmtu(struct dst_entry *dst, struct sock *sk,
29			     struct sk_buff *skb, u32 mtu)
 
30{
31}
32
33static void fake_redirect(struct dst_entry *dst, struct sock *sk,
34			  struct sk_buff *skb)
35{
36}
37
38static u32 *fake_cow_metrics(struct dst_entry *dst, unsigned long old)
39{
40	return NULL;
41}
42
43static struct neighbour *fake_neigh_lookup(const struct dst_entry *dst,
44					   struct sk_buff *skb,
45					   const void *daddr)
46{
47	return NULL;
48}
49
50static unsigned int fake_mtu(const struct dst_entry *dst)
51{
52	return dst->dev->mtu;
53}
54
55static struct dst_ops fake_dst_ops = {
56	.family		= AF_INET,
57	.update_pmtu	= fake_update_pmtu,
58	.redirect	= fake_redirect,
59	.cow_metrics	= fake_cow_metrics,
60	.neigh_lookup	= fake_neigh_lookup,
61	.mtu		= fake_mtu,
62};
63
64/*
65 * Initialize bogus route table used to keep netfilter happy.
66 * Currently, we fill in the PMTU entry because netfilter
67 * refragmentation needs it, and the rt_flags entry because
68 * ipt_REJECT needs it.  Future netfilter modules might
69 * require us to fill additional fields.
70 */
71static const u32 br_dst_default_metrics[RTAX_MAX] = {
72	[RTAX_MTU - 1] = 1500,
73};
74
75void br_netfilter_rtable_init(struct net_bridge *br)
76{
77	struct rtable *rt = &br->fake_rtable;
78
79	atomic_set(&rt->dst.__refcnt, 1);
80	rt->dst.dev = br->dev;
81	rt->dst.path = &rt->dst;
82	dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
83	rt->dst.flags	= DST_NOXFRM | DST_FAKE_RTABLE;
84	rt->dst.ops = &fake_dst_ops;
85}
86
87int __init br_nf_core_init(void)
88{
89	return dst_entries_init(&fake_dst_ops);
90}
91
92void br_nf_core_fini(void)
93{
94	dst_entries_destroy(&fake_dst_ops);
95}

 1// SPDX-License-Identifier: GPL-2.0-or-later
 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 *
 
 
 
 
 
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
24static void fake_update_pmtu(struct dst_entry *dst, struct sock *sk,
25			     struct sk_buff *skb, u32 mtu,
26			     bool confirm_neigh)
27{
28}
29
30static void fake_redirect(struct dst_entry *dst, struct sock *sk,
31			  struct sk_buff *skb)
32{
33}
34
35static u32 *fake_cow_metrics(struct dst_entry *dst, unsigned long old)
36{
37	return NULL;
38}
39
40static struct neighbour *fake_neigh_lookup(const struct dst_entry *dst,
41					   struct sk_buff *skb,
42					   const void *daddr)
43{
44	return NULL;
45}
46
47static unsigned int fake_mtu(const struct dst_entry *dst)
48{
49	return dst->dev->mtu;
50}
51
52static struct dst_ops fake_dst_ops = {
53	.family		= AF_INET,
54	.update_pmtu	= fake_update_pmtu,
55	.redirect	= fake_redirect,
56	.cow_metrics	= fake_cow_metrics,
57	.neigh_lookup	= fake_neigh_lookup,
58	.mtu		= fake_mtu,
59};
60
61/*
62 * Initialize bogus route table used to keep netfilter happy.
63 * Currently, we fill in the PMTU entry because netfilter
64 * refragmentation needs it, and the rt_flags entry because
65 * ipt_REJECT needs it.  Future netfilter modules might
66 * require us to fill additional fields.
67 */
68static const u32 br_dst_default_metrics[RTAX_MAX] = {
69	[RTAX_MTU - 1] = 1500,
70};
71
72void br_netfilter_rtable_init(struct net_bridge *br)
73{
74	struct rtable *rt = &br->fake_rtable;
75
76	atomic_set(&rt->dst.__refcnt, 1);
77	rt->dst.dev = br->dev;
 
78	dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
79	rt->dst.flags	= DST_NOXFRM | DST_FAKE_RTABLE;
80	rt->dst.ops = &fake_dst_ops;
81}
82
83int __init br_nf_core_init(void)
84{
85	return dst_entries_init(&fake_dst_ops);
86}
87
88void br_nf_core_fini(void)
89{
90	dst_entries_destroy(&fake_dst_ops);
91}