2005-04-17 00:20:36 +02:00
|
|
|
/*
|
|
|
|
* Handle firewalling
|
|
|
|
* Linux ethernet bridge
|
|
|
|
*
|
|
|
|
* Authors:
|
|
|
|
* Lennert Buytenhek <buytenh@gnu.org>
|
|
|
|
* Bart De Schuymer (maintainer) <bdschuym@pandora.be>
|
|
|
|
*
|
|
|
|
* Changes:
|
|
|
|
* Apr 29 2003: physdev module support (bdschuym)
|
|
|
|
* Jun 19 2003: let arptables see bridged ARP traffic (bdschuym)
|
|
|
|
* Oct 06 2003: filter encapsulated IP/ARP VLAN traffic on untagged bridge
|
|
|
|
* (bdschuym)
|
|
|
|
* Sep 01 2004: add IPv6 filtering (bdschuym)
|
|
|
|
*
|
|
|
|
* 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.
|
|
|
|
*
|
|
|
|
* Lennert dedicates this file to Kerstin Wurdinger.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/kernel.h>
|
|
|
|
#include <linux/ip.h>
|
|
|
|
#include <linux/netdevice.h>
|
|
|
|
#include <linux/skbuff.h>
|
2005-12-27 05:43:12 +01:00
|
|
|
#include <linux/if_arp.h>
|
2005-04-17 00:20:36 +02:00
|
|
|
#include <linux/if_ether.h>
|
|
|
|
#include <linux/if_vlan.h>
|
|
|
|
#include <linux/netfilter_bridge.h>
|
|
|
|
#include <linux/netfilter_ipv4.h>
|
|
|
|
#include <linux/netfilter_ipv6.h>
|
|
|
|
#include <linux/netfilter_arp.h>
|
|
|
|
#include <linux/in_route.h>
|
2005-12-27 05:43:12 +01:00
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
#include <net/ip.h>
|
|
|
|
#include <net/ipv6.h>
|
2005-12-27 05:43:12 +01:00
|
|
|
#include <net/route.h>
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
#include <asm/uaccess.h>
|
|
|
|
#include <asm/checksum.h>
|
|
|
|
#include "br_private.h"
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
#include <linux/sysctl.h>
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#define skb_origaddr(skb) (((struct bridge_skb_cb *) \
|
|
|
|
(skb->nf_bridge->data))->daddr.ipv4)
|
|
|
|
#define store_orig_dstaddr(skb) (skb_origaddr(skb) = (skb)->nh.iph->daddr)
|
|
|
|
#define dnat_took_place(skb) (skb_origaddr(skb) != (skb)->nh.iph->daddr)
|
|
|
|
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
static struct ctl_table_header *brnf_sysctl_header;
|
|
|
|
static int brnf_call_iptables = 1;
|
|
|
|
static int brnf_call_ip6tables = 1;
|
|
|
|
static int brnf_call_arptables = 1;
|
|
|
|
static int brnf_filter_vlan_tagged = 1;
|
|
|
|
#else
|
|
|
|
#define brnf_filter_vlan_tagged 1
|
|
|
|
#endif
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
static __be16 inline vlan_proto(const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
return vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
|
|
|
|
}
|
|
|
|
|
|
|
|
#define IS_VLAN_IP(skb) \
|
|
|
|
(skb->protocol == htons(ETH_P_8021Q) && \
|
|
|
|
vlan_proto(skb) == htons(ETH_P_IP) && \
|
|
|
|
brnf_filter_vlan_tagged)
|
|
|
|
|
|
|
|
#define IS_VLAN_IPV6(skb) \
|
|
|
|
(skb->protocol == htons(ETH_P_8021Q) && \
|
|
|
|
vlan_proto(skb) == htons(ETH_P_IPV6) &&\
|
|
|
|
brnf_filter_vlan_tagged)
|
|
|
|
|
|
|
|
#define IS_VLAN_ARP(skb) \
|
|
|
|
(skb->protocol == htons(ETH_P_8021Q) && \
|
|
|
|
vlan_proto(skb) == htons(ETH_P_ARP) && \
|
|
|
|
brnf_filter_vlan_tagged)
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
/* We need these fake structures to make netfilter happy --
|
|
|
|
* lots of places assume that skb->dst != NULL, which isn't
|
|
|
|
* all that unreasonable.
|
|
|
|
*
|
|
|
|
* 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 struct net_device __fake_net_device = {
|
|
|
|
.hard_header_len = ETH_HLEN
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct rtable __fake_rtable = {
|
|
|
|
.u = {
|
|
|
|
.dst = {
|
|
|
|
.__refcnt = ATOMIC_INIT(1),
|
|
|
|
.dev = &__fake_net_device,
|
|
|
|
.path = &__fake_rtable.u.dst,
|
|
|
|
.metrics = {[RTAX_MTU - 1] = 1500},
|
2006-02-21 22:37:35 +01:00
|
|
|
.flags = DST_NOXFRM,
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
},
|
|
|
|
.rt_flags = 0,
|
|
|
|
};
|
|
|
|
|
2006-02-10 02:09:38 +01:00
|
|
|
static inline struct net_device *bridge_parent(const struct net_device *dev)
|
|
|
|
{
|
|
|
|
struct net_bridge_port *port = rcu_dereference(dev->br_port);
|
|
|
|
|
|
|
|
return port ? port->br->dev : NULL;
|
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2006-03-21 07:58:21 +01:00
|
|
|
static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
skb->nf_bridge = kzalloc(sizeof(struct nf_bridge_info), GFP_ATOMIC);
|
|
|
|
if (likely(skb->nf_bridge))
|
|
|
|
atomic_set(&(skb->nf_bridge->use), 1);
|
|
|
|
|
|
|
|
return skb->nf_bridge;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void nf_bridge_save_header(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
int header_size = 16;
|
|
|
|
|
|
|
|
if (skb->protocol == htons(ETH_P_8021Q))
|
|
|
|
header_size = 18;
|
|
|
|
|
|
|
|
memcpy(skb->nf_bridge->data, skb->data - header_size, header_size);
|
|
|
|
}
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/* PF_BRIDGE/PRE_ROUTING *********************************************/
|
|
|
|
/* Undo the changes made for ip6tables PREROUTING and continue the
|
|
|
|
* bridge PRE_ROUTING hook. */
|
|
|
|
static int br_nf_pre_routing_finish_ipv6(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
|
|
|
|
|
|
|
|
if (nf_bridge->mask & BRNF_PKT_TYPE) {
|
|
|
|
skb->pkt_type = PACKET_OTHERHOST;
|
|
|
|
nf_bridge->mask ^= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING;
|
|
|
|
|
|
|
|
skb->dst = (struct dst_entry *)&__fake_rtable;
|
|
|
|
dst_hold(skb->dst);
|
|
|
|
|
|
|
|
skb->dev = nf_bridge->physindev;
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
|
|
|
|
br_handle_frame_finish, 1);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __br_dnat_complain(void)
|
|
|
|
{
|
|
|
|
static unsigned long last_complaint;
|
|
|
|
|
|
|
|
if (jiffies - last_complaint >= 5 * HZ) {
|
|
|
|
printk(KERN_WARNING "Performing cross-bridge DNAT requires IP "
|
2006-03-21 07:57:32 +01:00
|
|
|
"forwarding to be enabled\n");
|
2005-04-17 00:20:36 +02:00
|
|
|
last_complaint = jiffies;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* This requires some explaining. If DNAT has taken place,
|
|
|
|
* we will need to fix up the destination Ethernet address,
|
|
|
|
* and this is a tricky process.
|
|
|
|
*
|
|
|
|
* There are two cases to consider:
|
|
|
|
* 1. The packet was DNAT'ed to a device in the same bridge
|
|
|
|
* port group as it was received on. We can still bridge
|
|
|
|
* the packet.
|
|
|
|
* 2. The packet was DNAT'ed to a different device, either
|
|
|
|
* a non-bridged device or another bridge port group.
|
|
|
|
* The packet will need to be routed.
|
|
|
|
*
|
|
|
|
* The correct way of distinguishing between these two cases is to
|
|
|
|
* call ip_route_input() and to look at skb->dst->dev, which is
|
|
|
|
* changed to the destination device if ip_route_input() succeeds.
|
|
|
|
*
|
|
|
|
* Let us first consider the case that ip_route_input() succeeds:
|
|
|
|
*
|
|
|
|
* If skb->dst->dev equals the logical bridge device the packet
|
|
|
|
* came in on, we can consider this bridging. We then call
|
|
|
|
* skb->dst->output() which will make the packet enter br_nf_local_out()
|
|
|
|
* not much later. In that function it is assured that the iptables
|
|
|
|
* FORWARD chain is traversed for the packet.
|
|
|
|
*
|
|
|
|
* Otherwise, the packet is considered to be routed and we just
|
|
|
|
* change the destination MAC address so that the packet will
|
|
|
|
* later be passed up to the IP stack to be routed.
|
|
|
|
*
|
|
|
|
* Let us now consider the case that ip_route_input() fails:
|
|
|
|
*
|
|
|
|
* After a "echo '0' > /proc/sys/net/ipv4/ip_forward" ip_route_input()
|
|
|
|
* will fail, while __ip_route_output_key() will return success. The source
|
|
|
|
* address for __ip_route_output_key() is set to zero, so __ip_route_output_key
|
|
|
|
* thinks we're handling a locally generated packet and won't care
|
|
|
|
* if IP forwarding is allowed. We send a warning message to the users's
|
|
|
|
* log telling her to put IP forwarding on.
|
|
|
|
*
|
|
|
|
* ip_route_input() will also fail if there is no route available.
|
|
|
|
* In that case we just drop the packet.
|
|
|
|
*
|
|
|
|
* --Lennert, 20020411
|
|
|
|
* --Bart, 20020416 (updated)
|
|
|
|
* --Bart, 20021007 (updated) */
|
|
|
|
static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
if (skb->pkt_type == PACKET_OTHERHOST) {
|
|
|
|
skb->pkt_type = PACKET_HOST;
|
|
|
|
skb->nf_bridge->mask |= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
skb->nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING;
|
|
|
|
|
|
|
|
skb->dev = bridge_parent(skb->dev);
|
2006-02-10 02:09:38 +01:00
|
|
|
if (!skb->dev)
|
|
|
|
kfree_skb(skb);
|
|
|
|
else {
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2006-02-10 02:09:38 +01:00
|
|
|
skb_pull(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw += VLAN_HLEN;
|
|
|
|
}
|
|
|
|
skb->dst->output(skb);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int br_nf_pre_routing_finish(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct net_device *dev = skb->dev;
|
|
|
|
struct iphdr *iph = skb->nh.iph;
|
|
|
|
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
|
|
|
|
|
|
|
|
if (nf_bridge->mask & BRNF_PKT_TYPE) {
|
|
|
|
skb->pkt_type = PACKET_OTHERHOST;
|
|
|
|
nf_bridge->mask ^= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING;
|
|
|
|
|
|
|
|
if (dnat_took_place(skb)) {
|
2006-03-21 07:57:32 +01:00
|
|
|
if (ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
struct rtable *rt;
|
2006-03-21 07:57:32 +01:00
|
|
|
struct flowi fl = {
|
|
|
|
.nl_u = {
|
|
|
|
.ip4_u = {
|
|
|
|
.daddr = iph->daddr,
|
|
|
|
.saddr = 0,
|
|
|
|
.tos = RT_TOS(iph->tos) },
|
|
|
|
},
|
|
|
|
.proto = 0,
|
|
|
|
};
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
if (!ip_route_output_key(&rt, &fl)) {
|
2005-09-15 05:55:16 +02:00
|
|
|
/* - Bridged-and-DNAT'ed traffic doesn't
|
|
|
|
* require ip_forwarding.
|
|
|
|
* - Deal with redirected traffic. */
|
|
|
|
if (((struct dst_entry *)rt)->dev == dev ||
|
|
|
|
rt->rt_type == RTN_LOCAL) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb->dst = (struct dst_entry *)rt;
|
|
|
|
goto bridged_dnat;
|
|
|
|
}
|
|
|
|
__br_dnat_complain();
|
|
|
|
dst_release((struct dst_entry *)rt);
|
|
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
|
|
return 0;
|
|
|
|
} else {
|
|
|
|
if (skb->dst->dev == dev) {
|
|
|
|
bridged_dnat:
|
|
|
|
/* Tell br_nf_local_out this is a
|
|
|
|
* bridged frame */
|
|
|
|
nf_bridge->mask |= BRNF_BRIDGED_DNAT;
|
|
|
|
skb->dev = nf_bridge->physindev;
|
|
|
|
if (skb->protocol ==
|
2006-03-21 07:57:46 +01:00
|
|
|
htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING,
|
|
|
|
skb, skb->dev, NULL,
|
|
|
|
br_nf_pre_routing_finish_bridge,
|
|
|
|
1);
|
|
|
|
return 0;
|
|
|
|
}
|
2006-03-21 07:57:32 +01:00
|
|
|
memcpy(eth_hdr(skb)->h_dest, dev->dev_addr, ETH_ALEN);
|
2005-04-17 00:20:36 +02:00
|
|
|
skb->pkt_type = PACKET_HOST;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
skb->dst = (struct dst_entry *)&__fake_rtable;
|
|
|
|
dst_hold(skb->dst);
|
|
|
|
}
|
|
|
|
|
|
|
|
skb->dev = nf_bridge->physindev;
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
|
|
|
|
br_handle_frame_finish, 1);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Some common code for IPv4/IPv6 */
|
2006-02-10 02:09:38 +01:00
|
|
|
static struct net_device *setup_pre_routing(struct sk_buff *skb)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
|
|
|
|
|
|
|
|
if (skb->pkt_type == PACKET_OTHERHOST) {
|
|
|
|
skb->pkt_type = PACKET_HOST;
|
|
|
|
nf_bridge->mask |= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
|
|
|
|
nf_bridge->mask |= BRNF_NF_BRIDGE_PREROUTING;
|
|
|
|
nf_bridge->physindev = skb->dev;
|
|
|
|
skb->dev = bridge_parent(skb->dev);
|
2006-02-10 02:09:38 +01:00
|
|
|
|
|
|
|
return skb->dev;
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
/* We only check the length. A bridge shouldn't do any hop-by-hop stuff anyway */
|
|
|
|
static int check_hbh_len(struct sk_buff *skb)
|
|
|
|
{
|
2006-03-21 07:57:32 +01:00
|
|
|
unsigned char *raw = (u8 *) (skb->nh.ipv6h + 1);
|
2005-04-17 00:20:36 +02:00
|
|
|
u32 pkt_len;
|
|
|
|
int off = raw - skb->nh.raw;
|
2006-03-21 07:57:32 +01:00
|
|
|
int len = (raw[1] + 1) << 3;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
if ((raw + len) - skb->data > skb_headlen(skb))
|
|
|
|
goto bad;
|
|
|
|
|
|
|
|
off += 2;
|
|
|
|
len -= 2;
|
|
|
|
|
|
|
|
while (len > 0) {
|
2006-03-21 07:57:32 +01:00
|
|
|
int optlen = skb->nh.raw[off + 1] + 2;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
switch (skb->nh.raw[off]) {
|
|
|
|
case IPV6_TLV_PAD0:
|
|
|
|
optlen = 1;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case IPV6_TLV_PADN:
|
|
|
|
break;
|
|
|
|
|
|
|
|
case IPV6_TLV_JUMBO:
|
2006-03-21 07:57:32 +01:00
|
|
|
if (skb->nh.raw[off + 1] != 4 || (off & 3) != 2)
|
2005-04-17 00:20:36 +02:00
|
|
|
goto bad;
|
2006-03-21 07:57:32 +01:00
|
|
|
pkt_len = ntohl(*(u32 *) (skb->nh.raw + off + 2));
|
2005-12-19 23:00:08 +01:00
|
|
|
if (pkt_len <= IPV6_MAXPLEN ||
|
|
|
|
skb->nh.ipv6h->payload_len)
|
|
|
|
goto bad;
|
2005-04-17 00:20:36 +02:00
|
|
|
if (pkt_len > skb->len - sizeof(struct ipv6hdr))
|
|
|
|
goto bad;
|
2005-12-19 23:00:08 +01:00
|
|
|
if (pskb_trim_rcsum(skb,
|
2006-03-21 07:57:32 +01:00
|
|
|
pkt_len + sizeof(struct ipv6hdr)))
|
2005-12-19 23:00:08 +01:00
|
|
|
goto bad;
|
2005-04-17 00:20:36 +02:00
|
|
|
break;
|
|
|
|
default:
|
|
|
|
if (optlen > len)
|
|
|
|
goto bad;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
off += optlen;
|
|
|
|
len -= optlen;
|
|
|
|
}
|
|
|
|
if (len == 0)
|
|
|
|
return 0;
|
|
|
|
bad:
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Replicate the checks that IPv6 does on packet reception and pass the packet
|
|
|
|
* to ip6tables, which doesn't support NAT, so things are fairly simple. */
|
|
|
|
static unsigned int br_nf_pre_routing_ipv6(unsigned int hook,
|
2006-03-21 07:57:32 +01:00
|
|
|
struct sk_buff *skb,
|
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct ipv6hdr *hdr;
|
|
|
|
u32 pkt_len;
|
|
|
|
|
|
|
|
if (skb->len < sizeof(struct ipv6hdr))
|
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
|
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
hdr = skb->nh.ipv6h;
|
|
|
|
|
|
|
|
if (hdr->version != 6)
|
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
pkt_len = ntohs(hdr->payload_len);
|
|
|
|
|
|
|
|
if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
|
|
|
|
if (pkt_len + sizeof(struct ipv6hdr) > skb->len)
|
|
|
|
goto inhdr_error;
|
|
|
|
if (pkt_len + sizeof(struct ipv6hdr) < skb->len) {
|
|
|
|
if (__pskb_trim(skb, pkt_len + sizeof(struct ipv6hdr)))
|
|
|
|
goto inhdr_error;
|
|
|
|
if (skb->ip_summed == CHECKSUM_HW)
|
|
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb))
|
2006-03-21 07:57:32 +01:00
|
|
|
goto inhdr_error;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
2006-03-21 07:57:32 +01:00
|
|
|
nf_bridge_put(skb->nf_bridge);
|
2006-03-21 07:58:21 +01:00
|
|
|
if (!nf_bridge_alloc(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
return NF_DROP;
|
2006-02-10 02:09:38 +01:00
|
|
|
if (!setup_pre_routing(skb))
|
|
|
|
return NF_DROP;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
|
|
|
|
br_nf_pre_routing_finish_ipv6);
|
|
|
|
|
|
|
|
return NF_STOLEN;
|
|
|
|
|
|
|
|
inhdr_error:
|
|
|
|
return NF_DROP;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Direct IPv6 traffic to br_nf_pre_routing_ipv6.
|
|
|
|
* Replicate the checks that IPv4 does on packet reception.
|
|
|
|
* Set skb->dev to the bridge device (i.e. parent of the
|
|
|
|
* receiving device) to make netfilter happy, the REDIRECT
|
|
|
|
* target in particular. Save the original destination IP
|
|
|
|
* address to be able to detect DNAT afterwards. */
|
|
|
|
static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
|
2006-01-06 22:13:29 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct iphdr *iph;
|
|
|
|
__u32 len;
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_IPV6) || IS_VLAN_IPV6(skb)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
if (!brnf_call_ip6tables)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
#endif
|
|
|
|
if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
|
|
|
|
goto out;
|
|
|
|
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2006-03-21 07:43:56 +01:00
|
|
|
skb_pull_rcsum(skb, VLAN_HLEN);
|
2006-01-06 22:13:29 +01:00
|
|
|
skb->nh.raw += VLAN_HLEN;
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
return br_nf_pre_routing_ipv6(hook, skb, in, out, okfn);
|
|
|
|
}
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
if (!brnf_call_iptables)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
#endif
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
if (skb->protocol != htons(ETH_P_IP) && !IS_VLAN_IP(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
return NF_ACCEPT;
|
|
|
|
|
|
|
|
if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
|
|
|
|
goto out;
|
|
|
|
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2006-03-21 07:43:56 +01:00
|
|
|
skb_pull_rcsum(skb, VLAN_HLEN);
|
2006-01-06 22:13:29 +01:00
|
|
|
skb->nh.raw += VLAN_HLEN;
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
|
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
iph = skb->nh.iph;
|
|
|
|
if (iph->ihl < 5 || iph->version != 4)
|
|
|
|
goto inhdr_error;
|
|
|
|
|
2006-03-21 07:57:32 +01:00
|
|
|
if (!pskb_may_pull(skb, 4 * iph->ihl))
|
2005-04-17 00:20:36 +02:00
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
iph = skb->nh.iph;
|
2006-03-21 07:57:32 +01:00
|
|
|
if (ip_fast_csum((__u8 *) iph, iph->ihl) != 0)
|
2005-04-17 00:20:36 +02:00
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
len = ntohs(iph->tot_len);
|
2006-03-21 07:57:32 +01:00
|
|
|
if (skb->len < len || len < 4 * iph->ihl)
|
2005-04-17 00:20:36 +02:00
|
|
|
goto inhdr_error;
|
|
|
|
|
|
|
|
if (skb->len > len) {
|
|
|
|
__pskb_trim(skb, len);
|
|
|
|
if (skb->ip_summed == CHECKSUM_HW)
|
|
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
|
|
}
|
|
|
|
|
2006-03-21 07:57:32 +01:00
|
|
|
nf_bridge_put(skb->nf_bridge);
|
2006-03-21 07:58:21 +01:00
|
|
|
if (!nf_bridge_alloc(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
return NF_DROP;
|
2006-02-10 02:09:38 +01:00
|
|
|
if (!setup_pre_routing(skb))
|
|
|
|
return NF_DROP;
|
2005-04-17 00:20:36 +02:00
|
|
|
store_orig_dstaddr(skb);
|
|
|
|
|
|
|
|
NF_HOOK(PF_INET, NF_IP_PRE_ROUTING, skb, skb->dev, NULL,
|
|
|
|
br_nf_pre_routing_finish);
|
|
|
|
|
|
|
|
return NF_STOLEN;
|
|
|
|
|
|
|
|
inhdr_error:
|
2006-03-21 07:57:32 +01:00
|
|
|
// IP_INC_STATS_BH(IpInHdrErrors);
|
2005-04-17 00:20:36 +02:00
|
|
|
out:
|
|
|
|
return NF_DROP;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/* PF_BRIDGE/LOCAL_IN ************************************************/
|
|
|
|
/* The packet is locally destined, which requires a real
|
|
|
|
* dst_entry, so detach the fake one. On the way up, the
|
|
|
|
* packet would pass through PRE_ROUTING again (which already
|
|
|
|
* took place when the packet entered the bridge), but we
|
|
|
|
* register an IPv4 PRE_ROUTING 'sabotage' hook that will
|
|
|
|
* prevent this from happening. */
|
|
|
|
static unsigned int br_nf_local_in(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
|
|
|
|
if (skb->dst == (struct dst_entry *)&__fake_rtable) {
|
|
|
|
dst_release(skb->dst);
|
|
|
|
skb->dst = NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* PF_BRIDGE/FORWARD *************************************************/
|
|
|
|
static int br_nf_forward_finish(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
|
|
|
|
struct net_device *in;
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
if (skb->protocol != htons(ETH_P_ARP) && !IS_VLAN_ARP(skb)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
in = nf_bridge->physindev;
|
|
|
|
if (nf_bridge->mask & BRNF_PKT_TYPE) {
|
|
|
|
skb->pkt_type = PACKET_OTHERHOST;
|
|
|
|
nf_bridge->mask ^= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
in = *((struct net_device **)(skb->cb));
|
|
|
|
}
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_FORWARD, skb, in,
|
2006-03-21 07:57:32 +01:00
|
|
|
skb->dev, br_forward_finish, 1);
|
2005-04-17 00:20:36 +02:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* This is the 'purely bridged' case. For IP, we pass the packet to
|
|
|
|
* netfilter with indev and outdev set to the bridge device,
|
|
|
|
* but we are still able to filter on the 'real' indev/outdev
|
|
|
|
* because of the physdev module. For ARP, indev and outdev are the
|
|
|
|
* bridge ports. */
|
|
|
|
static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
struct nf_bridge_info *nf_bridge;
|
2006-02-10 02:09:38 +01:00
|
|
|
struct net_device *parent;
|
2005-04-17 00:20:36 +02:00
|
|
|
int pf;
|
|
|
|
|
|
|
|
if (!skb->nf_bridge)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
|
2006-02-10 02:09:38 +01:00
|
|
|
parent = bridge_parent(out);
|
|
|
|
if (!parent)
|
|
|
|
return NF_DROP;
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
pf = PF_INET;
|
|
|
|
else
|
|
|
|
pf = PF_INET6;
|
|
|
|
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_pull(*pskb, VLAN_HLEN);
|
|
|
|
(*pskb)->nh.raw += VLAN_HLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
nf_bridge = skb->nf_bridge;
|
|
|
|
if (skb->pkt_type == PACKET_OTHERHOST) {
|
|
|
|
skb->pkt_type = PACKET_HOST;
|
|
|
|
nf_bridge->mask |= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* The physdev module checks on this */
|
|
|
|
nf_bridge->mask |= BRNF_BRIDGED;
|
|
|
|
nf_bridge->physoutdev = skb->dev;
|
|
|
|
|
2006-02-10 02:09:38 +01:00
|
|
|
NF_HOOK(pf, NF_IP_FORWARD, skb, bridge_parent(in), parent,
|
|
|
|
br_nf_forward_finish);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
return NF_STOLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
struct net_device **d = (struct net_device **)(skb->cb);
|
|
|
|
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
if (!brnf_call_arptables)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
#endif
|
|
|
|
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol != htons(ETH_P_ARP)) {
|
2006-03-21 07:58:05 +01:00
|
|
|
if (!IS_VLAN_ARP(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
return NF_ACCEPT;
|
|
|
|
skb_pull(*pskb, VLAN_HLEN);
|
|
|
|
(*pskb)->nh.raw += VLAN_HLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (skb->nh.arph->ar_pln != 4) {
|
2006-03-21 07:58:05 +01:00
|
|
|
if (IS_VLAN_ARP(skb)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(*pskb, VLAN_HLEN);
|
|
|
|
(*pskb)->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
*d = (struct net_device *)in;
|
|
|
|
NF_HOOK(NF_ARP, NF_ARP_FORWARD, skb, (struct net_device *)in,
|
|
|
|
(struct net_device *)out, br_nf_forward_finish);
|
|
|
|
|
|
|
|
return NF_STOLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* PF_BRIDGE/LOCAL_OUT ***********************************************/
|
|
|
|
static int br_nf_local_out_finish(struct sk_buff *skb)
|
|
|
|
{
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
|
2006-03-21 07:57:32 +01:00
|
|
|
br_forward_finish, NF_BR_PRI_FIRST + 1);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* This function sees both locally originated IP packets and forwarded
|
|
|
|
* IP packets (in both cases the destination device is a bridge
|
|
|
|
* device). It also sees bridged-and-DNAT'ed packets.
|
|
|
|
* To be able to filter on the physical bridge devices (with the physdev
|
|
|
|
* module), we steal packets destined to a bridge device away from the
|
|
|
|
* PF_INET/FORWARD and PF_INET/OUTPUT hook functions, and give them back later,
|
|
|
|
* when we have determined the real output device. This is done in here.
|
|
|
|
*
|
|
|
|
* If (nf_bridge->mask & BRNF_BRIDGED_DNAT) then the packet is bridged
|
|
|
|
* and we fake the PF_BRIDGE/FORWARD hook. The function br_nf_forward()
|
|
|
|
* will then fake the PF_INET/FORWARD hook. br_nf_local_out() has priority
|
|
|
|
* NF_BR_PRI_FIRST, so no relevant PF_BRIDGE/INPUT functions have been nor
|
|
|
|
* will be executed.
|
|
|
|
* Otherwise, if nf_bridge->physindev is NULL, the bridge-nf code never touched
|
|
|
|
* this packet before, and so the packet was locally originated. We fake
|
|
|
|
* the PF_INET/LOCAL_OUT hook.
|
|
|
|
* Finally, if nf_bridge->physindev isn't NULL, then the packet was IP routed,
|
|
|
|
* so we fake the PF_INET/FORWARD hook. ip_sabotage_out() makes sure
|
|
|
|
* even routed packets that didn't arrive on a bridge interface have their
|
|
|
|
* nf_bridge->physindev set. */
|
|
|
|
static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct net_device *realindev, *realoutdev;
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
struct nf_bridge_info *nf_bridge;
|
|
|
|
int pf;
|
|
|
|
|
|
|
|
if (!skb->nf_bridge)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
pf = PF_INET;
|
|
|
|
else
|
|
|
|
pf = PF_INET6;
|
|
|
|
|
|
|
|
#ifdef CONFIG_NETFILTER_DEBUG
|
|
|
|
/* Sometimes we get packets with NULL ->dst here (for example,
|
|
|
|
* running a dhcp client daemon triggers this). This should now
|
|
|
|
* be fixed, but let's keep the check around. */
|
|
|
|
if (skb->dst == NULL) {
|
|
|
|
printk(KERN_CRIT "br_netfilter: skb->dst == NULL.");
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
nf_bridge = skb->nf_bridge;
|
|
|
|
nf_bridge->physoutdev = skb->dev;
|
|
|
|
realindev = nf_bridge->physindev;
|
|
|
|
|
|
|
|
/* Bridged, take PF_BRIDGE/FORWARD.
|
|
|
|
* (see big note in front of br_nf_pre_routing_finish) */
|
|
|
|
if (nf_bridge->mask & BRNF_BRIDGED_DNAT) {
|
|
|
|
if (nf_bridge->mask & BRNF_PKT_TYPE) {
|
|
|
|
skb->pkt_type = PACKET_OTHERHOST;
|
|
|
|
nf_bridge->mask ^= BRNF_PKT_TYPE;
|
|
|
|
}
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_push(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw -= VLAN_HLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev,
|
|
|
|
skb->dev, br_forward_finish);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
realoutdev = bridge_parent(skb->dev);
|
2006-02-10 02:09:38 +01:00
|
|
|
if (!realoutdev)
|
|
|
|
return NF_DROP;
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
|
|
|
|
/* iptables should match -o br0.x */
|
|
|
|
if (nf_bridge->netoutdev)
|
|
|
|
realoutdev = nf_bridge->netoutdev;
|
|
|
|
#endif
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_pull(skb, VLAN_HLEN);
|
|
|
|
(*pskb)->nh.raw += VLAN_HLEN;
|
|
|
|
}
|
|
|
|
/* IP forwarded traffic has a physindev, locally
|
|
|
|
* generated traffic hasn't. */
|
|
|
|
if (realindev != NULL) {
|
2006-03-21 07:57:32 +01:00
|
|
|
if (!(nf_bridge->mask & BRNF_DONT_TAKE_PARENT)) {
|
2006-02-10 02:09:38 +01:00
|
|
|
struct net_device *parent = bridge_parent(realindev);
|
|
|
|
if (parent)
|
|
|
|
realindev = parent;
|
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
NF_HOOK_THRESH(pf, NF_IP_FORWARD, skb, realindev,
|
|
|
|
realoutdev, br_nf_local_out_finish,
|
|
|
|
NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD + 1);
|
|
|
|
} else {
|
|
|
|
NF_HOOK_THRESH(pf, NF_IP_LOCAL_OUT, skb, realindev,
|
|
|
|
realoutdev, br_nf_local_out_finish,
|
|
|
|
NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT + 1);
|
|
|
|
}
|
|
|
|
|
|
|
|
out:
|
|
|
|
return NF_STOLEN;
|
|
|
|
}
|
|
|
|
|
2006-04-04 22:42:35 +02:00
|
|
|
static int br_nf_dev_queue_xmit(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
if (skb->protocol == htons(ETH_P_IP) &&
|
|
|
|
skb->len > skb->dev->mtu &&
|
|
|
|
!(skb_shinfo(skb)->ufo_size || skb_shinfo(skb)->tso_size))
|
|
|
|
return ip_fragment(skb, br_dev_queue_push_xmit);
|
|
|
|
else
|
|
|
|
return br_dev_queue_push_xmit(skb);
|
|
|
|
}
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
/* PF_BRIDGE/POST_ROUTING ********************************************/
|
|
|
|
static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
struct nf_bridge_info *nf_bridge = (*pskb)->nf_bridge;
|
|
|
|
struct net_device *realoutdev = bridge_parent(skb->dev);
|
|
|
|
int pf;
|
|
|
|
|
|
|
|
#ifdef CONFIG_NETFILTER_DEBUG
|
|
|
|
/* Be very paranoid. This probably won't happen anymore, but let's
|
|
|
|
* keep the check just to be sure... */
|
|
|
|
if (skb->mac.raw < skb->head || skb->mac.raw + ETH_HLEN > skb->data) {
|
|
|
|
printk(KERN_CRIT "br_netfilter: Argh!! br_nf_post_routing: "
|
2006-03-21 07:57:32 +01:00
|
|
|
"bad mac.raw pointer.");
|
2005-04-17 00:20:36 +02:00
|
|
|
goto print_error;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
if (!nf_bridge)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
|
2006-02-10 02:09:38 +01:00
|
|
|
if (!realoutdev)
|
|
|
|
return NF_DROP;
|
|
|
|
|
2006-03-21 07:58:05 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb))
|
2005-04-17 00:20:36 +02:00
|
|
|
pf = PF_INET;
|
|
|
|
else
|
|
|
|
pf = PF_INET6;
|
|
|
|
|
|
|
|
#ifdef CONFIG_NETFILTER_DEBUG
|
|
|
|
if (skb->dst == NULL) {
|
|
|
|
printk(KERN_CRIT "br_netfilter: skb->dst == NULL.");
|
|
|
|
goto print_error;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* We assume any code from br_dev_queue_push_xmit onwards doesn't care
|
|
|
|
* about the value of skb->pkt_type. */
|
|
|
|
if (skb->pkt_type == PACKET_OTHERHOST) {
|
|
|
|
skb->pkt_type = PACKET_HOST;
|
|
|
|
nf_bridge->mask |= BRNF_PKT_TYPE;
|
|
|
|
}
|
|
|
|
|
2006-03-21 07:57:46 +01:00
|
|
|
if (skb->protocol == htons(ETH_P_8021Q)) {
|
2005-04-17 00:20:36 +02:00
|
|
|
skb_pull(skb, VLAN_HLEN);
|
|
|
|
skb->nh.raw += VLAN_HLEN;
|
|
|
|
}
|
|
|
|
|
|
|
|
nf_bridge_save_header(skb);
|
|
|
|
|
|
|
|
#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
|
|
|
|
if (nf_bridge->netoutdev)
|
|
|
|
realoutdev = nf_bridge->netoutdev;
|
|
|
|
#endif
|
|
|
|
NF_HOOK(pf, NF_IP_POST_ROUTING, skb, NULL, realoutdev,
|
2006-04-04 22:42:35 +02:00
|
|
|
br_nf_dev_queue_xmit);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
return NF_STOLEN;
|
|
|
|
|
|
|
|
#ifdef CONFIG_NETFILTER_DEBUG
|
|
|
|
print_error:
|
|
|
|
if (skb->dev != NULL) {
|
|
|
|
printk("[%s]", skb->dev->name);
|
2006-02-14 00:43:58 +01:00
|
|
|
if (realoutdev)
|
|
|
|
printk("[%s]", realoutdev->name);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
printk(" head:%p, raw:%p, data:%p\n", skb->head, skb->mac.raw,
|
2006-03-21 07:57:32 +01:00
|
|
|
skb->data);
|
2005-04-17 00:20:36 +02:00
|
|
|
return NF_ACCEPT;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
/* IP/SABOTAGE *****************************************************/
|
|
|
|
/* Don't hand locally destined packets to PF_INET(6)/PRE_ROUTING
|
|
|
|
* for the second time. */
|
|
|
|
static unsigned int ip_sabotage_in(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
if ((*pskb)->nf_bridge &&
|
|
|
|
!((*pskb)->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)) {
|
|
|
|
return NF_STOP;
|
|
|
|
}
|
|
|
|
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Postpone execution of PF_INET(6)/FORWARD, PF_INET(6)/LOCAL_OUT
|
|
|
|
* and PF_INET(6)/POST_ROUTING until we have done the forwarding
|
|
|
|
* decision in the bridge code and have determined nf_bridge->physoutdev. */
|
|
|
|
static unsigned int ip_sabotage_out(unsigned int hook, struct sk_buff **pskb,
|
2006-03-21 07:57:32 +01:00
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
int (*okfn)(struct sk_buff *))
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
struct sk_buff *skb = *pskb;
|
|
|
|
|
|
|
|
if ((out->hard_start_xmit == br_dev_xmit &&
|
2006-03-21 07:57:32 +01:00
|
|
|
okfn != br_nf_forward_finish &&
|
2006-04-04 22:42:35 +02:00
|
|
|
okfn != br_nf_local_out_finish && okfn != br_nf_dev_queue_xmit)
|
2005-04-17 00:20:36 +02:00
|
|
|
#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
|
|
|
|
|| ((out->priv_flags & IFF_802_1Q_VLAN) &&
|
2006-03-21 07:57:32 +01:00
|
|
|
VLAN_DEV_INFO(out)->real_dev->hard_start_xmit == br_dev_xmit)
|
2005-04-17 00:20:36 +02:00
|
|
|
#endif
|
|
|
|
) {
|
|
|
|
struct nf_bridge_info *nf_bridge;
|
|
|
|
|
|
|
|
if (!skb->nf_bridge) {
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
/* This code is executed while in the IP(v6) stack,
|
|
|
|
the version should be 4 or 6. We can't use
|
|
|
|
skb->protocol because that isn't set on
|
|
|
|
PF_INET(6)/LOCAL_OUT. */
|
|
|
|
struct iphdr *ip = skb->nh.iph;
|
|
|
|
|
|
|
|
if (ip->version == 4 && !brnf_call_iptables)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
else if (ip->version == 6 && !brnf_call_ip6tables)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
#endif
|
|
|
|
if (hook == NF_IP_POST_ROUTING)
|
|
|
|
return NF_ACCEPT;
|
|
|
|
if (!nf_bridge_alloc(skb))
|
|
|
|
return NF_DROP;
|
|
|
|
}
|
|
|
|
|
|
|
|
nf_bridge = skb->nf_bridge;
|
|
|
|
|
|
|
|
/* This frame will arrive on PF_BRIDGE/LOCAL_OUT and we
|
|
|
|
* will need the indev then. For a brouter, the real indev
|
|
|
|
* can be a bridge port, so we make sure br_nf_local_out()
|
|
|
|
* doesn't use the bridge parent of the indev by using
|
|
|
|
* the BRNF_DONT_TAKE_PARENT mask. */
|
|
|
|
if (hook == NF_IP_FORWARD && nf_bridge->physindev == NULL) {
|
2005-06-29 01:04:44 +02:00
|
|
|
nf_bridge->mask |= BRNF_DONT_TAKE_PARENT;
|
2005-04-17 00:20:36 +02:00
|
|
|
nf_bridge->physindev = (struct net_device *)in;
|
|
|
|
}
|
|
|
|
#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
|
|
|
|
/* the iptables outdev is br0.x, not br0 */
|
|
|
|
if (out->priv_flags & IFF_802_1Q_VLAN)
|
|
|
|
nf_bridge->netoutdev = (struct net_device *)out;
|
|
|
|
#endif
|
|
|
|
return NF_STOP;
|
|
|
|
}
|
|
|
|
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* For br_nf_local_out we need (prio = NF_BR_PRI_FIRST), to insure that innocent
|
|
|
|
* PF_BRIDGE/NF_BR_LOCAL_OUT functions don't get bridged traffic as input.
|
|
|
|
* For br_nf_post_routing, we need (prio = NF_BR_PRI_LAST), because
|
|
|
|
* ip_refrag() can return NF_STOLEN. */
|
|
|
|
static struct nf_hook_ops br_nf_ops[] = {
|
|
|
|
{ .hook = br_nf_pre_routing,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_BRIDGE,
|
|
|
|
.hooknum = NF_BR_PRE_ROUTING,
|
|
|
|
.priority = NF_BR_PRI_BRNF, },
|
|
|
|
{ .hook = br_nf_local_in,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_BRIDGE,
|
|
|
|
.hooknum = NF_BR_LOCAL_IN,
|
|
|
|
.priority = NF_BR_PRI_BRNF, },
|
|
|
|
{ .hook = br_nf_forward_ip,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_BRIDGE,
|
|
|
|
.hooknum = NF_BR_FORWARD,
|
|
|
|
.priority = NF_BR_PRI_BRNF - 1, },
|
|
|
|
{ .hook = br_nf_forward_arp,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_BRIDGE,
|
|
|
|
.hooknum = NF_BR_FORWARD,
|
|
|
|
.priority = NF_BR_PRI_BRNF, },
|
|
|
|
{ .hook = br_nf_local_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_BRIDGE,
|
|
|
|
.hooknum = NF_BR_LOCAL_OUT,
|
|
|
|
.priority = NF_BR_PRI_FIRST, },
|
|
|
|
{ .hook = br_nf_post_routing,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_BRIDGE,
|
|
|
|
.hooknum = NF_BR_POST_ROUTING,
|
|
|
|
.priority = NF_BR_PRI_LAST, },
|
|
|
|
{ .hook = ip_sabotage_in,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET,
|
|
|
|
.hooknum = NF_IP_PRE_ROUTING,
|
|
|
|
.priority = NF_IP_PRI_FIRST, },
|
|
|
|
{ .hook = ip_sabotage_in,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET6,
|
|
|
|
.hooknum = NF_IP6_PRE_ROUTING,
|
|
|
|
.priority = NF_IP6_PRI_FIRST, },
|
|
|
|
{ .hook = ip_sabotage_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET,
|
|
|
|
.hooknum = NF_IP_FORWARD,
|
|
|
|
.priority = NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD, },
|
|
|
|
{ .hook = ip_sabotage_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET6,
|
|
|
|
.hooknum = NF_IP6_FORWARD,
|
|
|
|
.priority = NF_IP6_PRI_BRIDGE_SABOTAGE_FORWARD, },
|
|
|
|
{ .hook = ip_sabotage_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET,
|
|
|
|
.hooknum = NF_IP_LOCAL_OUT,
|
|
|
|
.priority = NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, },
|
|
|
|
{ .hook = ip_sabotage_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET6,
|
|
|
|
.hooknum = NF_IP6_LOCAL_OUT,
|
|
|
|
.priority = NF_IP6_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, },
|
|
|
|
{ .hook = ip_sabotage_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET,
|
|
|
|
.hooknum = NF_IP_POST_ROUTING,
|
|
|
|
.priority = NF_IP_PRI_FIRST, },
|
|
|
|
{ .hook = ip_sabotage_out,
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.pf = PF_INET6,
|
|
|
|
.hooknum = NF_IP6_POST_ROUTING,
|
|
|
|
.priority = NF_IP6_PRI_FIRST, },
|
|
|
|
};
|
|
|
|
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
static
|
2006-03-21 07:57:32 +01:00
|
|
|
int brnf_sysctl_call_tables(ctl_table * ctl, int write, struct file *filp,
|
|
|
|
void __user * buffer, size_t * lenp, loff_t * ppos)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
|
|
|
|
|
|
|
|
if (write && *(int *)(ctl->data))
|
|
|
|
*(int *)(ctl->data) = 1;
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static ctl_table brnf_table[] = {
|
|
|
|
{
|
|
|
|
.ctl_name = NET_BRIDGE_NF_CALL_ARPTABLES,
|
|
|
|
.procname = "bridge-nf-call-arptables",
|
|
|
|
.data = &brnf_call_arptables,
|
|
|
|
.maxlen = sizeof(int),
|
|
|
|
.mode = 0644,
|
|
|
|
.proc_handler = &brnf_sysctl_call_tables,
|
|
|
|
},
|
|
|
|
{
|
|
|
|
.ctl_name = NET_BRIDGE_NF_CALL_IPTABLES,
|
|
|
|
.procname = "bridge-nf-call-iptables",
|
|
|
|
.data = &brnf_call_iptables,
|
|
|
|
.maxlen = sizeof(int),
|
|
|
|
.mode = 0644,
|
|
|
|
.proc_handler = &brnf_sysctl_call_tables,
|
|
|
|
},
|
|
|
|
{
|
|
|
|
.ctl_name = NET_BRIDGE_NF_CALL_IP6TABLES,
|
|
|
|
.procname = "bridge-nf-call-ip6tables",
|
|
|
|
.data = &brnf_call_ip6tables,
|
|
|
|
.maxlen = sizeof(int),
|
|
|
|
.mode = 0644,
|
|
|
|
.proc_handler = &brnf_sysctl_call_tables,
|
|
|
|
},
|
|
|
|
{
|
|
|
|
.ctl_name = NET_BRIDGE_NF_FILTER_VLAN_TAGGED,
|
|
|
|
.procname = "bridge-nf-filter-vlan-tagged",
|
|
|
|
.data = &brnf_filter_vlan_tagged,
|
|
|
|
.maxlen = sizeof(int),
|
|
|
|
.mode = 0644,
|
|
|
|
.proc_handler = &brnf_sysctl_call_tables,
|
|
|
|
},
|
|
|
|
{ .ctl_name = 0 }
|
|
|
|
};
|
|
|
|
|
|
|
|
static ctl_table brnf_bridge_table[] = {
|
|
|
|
{
|
|
|
|
.ctl_name = NET_BRIDGE,
|
|
|
|
.procname = "bridge",
|
|
|
|
.mode = 0555,
|
|
|
|
.child = brnf_table,
|
|
|
|
},
|
|
|
|
{ .ctl_name = 0 }
|
|
|
|
};
|
|
|
|
|
|
|
|
static ctl_table brnf_net_table[] = {
|
|
|
|
{
|
|
|
|
.ctl_name = CTL_NET,
|
|
|
|
.procname = "net",
|
|
|
|
.mode = 0555,
|
|
|
|
.child = brnf_bridge_table,
|
|
|
|
},
|
|
|
|
{ .ctl_name = 0 }
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
|
|
|
int br_netfilter_init(void)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < ARRAY_SIZE(br_nf_ops); i++) {
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
if ((ret = nf_register_hook(&br_nf_ops[i])) >= 0)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
while (i--)
|
|
|
|
nf_unregister_hook(&br_nf_ops[i]);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
brnf_sysctl_header = register_sysctl_table(brnf_net_table, 0);
|
|
|
|
if (brnf_sysctl_header == NULL) {
|
2006-03-21 07:57:32 +01:00
|
|
|
printk(KERN_WARNING
|
|
|
|
"br_netfilter: can't register to sysctl.\n");
|
2005-04-17 00:20:36 +02:00
|
|
|
for (i = 0; i < ARRAY_SIZE(br_nf_ops); i++)
|
|
|
|
nf_unregister_hook(&br_nf_ops[i]);
|
|
|
|
return -EFAULT;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
printk(KERN_NOTICE "Bridge firewalling registered\n");
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
void br_netfilter_fini(void)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = ARRAY_SIZE(br_nf_ops) - 1; i >= 0; i--)
|
|
|
|
nf_unregister_hook(&br_nf_ops[i]);
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
unregister_sysctl_table(brnf_sysctl_header);
|
|
|
|
#endif
|
|
|
|
}
|