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/*
* Handle incoming frames
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* $Id: br_input.c,v 1.9 2001/08/14 22:05:57 davem Exp $
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_bridge.h>
#include <linux/netfilter_bridge.h>
#include "br_private.h"
unsigned char bridge_ula[6] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
static int br_pass_frame_up_finish(struct sk_buff *skb)
{
netif_rx(skb);
return 0;
}
static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb)
{
struct net_device *indev;
br->statistics.rx_packets++;
br->statistics.rx_bytes += skb->len;
indev = skb->dev;
skb->dev = &br->dev;
skb->pkt_type = PACKET_HOST;
skb_push(skb, ETH_HLEN);
skb->protocol = eth_type_trans(skb, &br->dev);
NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, indev, NULL,
br_pass_frame_up_finish);
}
static void __br_handle_frame(struct sk_buff *skb)
{
struct net_bridge *br;
unsigned char *dest;
struct net_bridge_fdb_entry *dst;
struct net_bridge_port *p;
int passedup;
dest = skb->mac.ethernet->h_dest;
p = skb->dev->br_port;
br = p->br;
passedup = 0;
if (!(br->dev.flags & IFF_UP) ||
p->state == BR_STATE_DISABLED)
goto freeandout;
if (br->dev.flags & IFF_PROMISC) {
struct sk_buff *skb2;
skb2 = skb_clone(skb, GFP_ATOMIC);
if (skb2) {
passedup = 1;
br_pass_frame_up(br, skb2);
}
}
if (skb->mac.ethernet->h_source[0] & 1)
goto freeandout;
if (!passedup &&
(dest[0] & 1) &&
(br->dev.flags & IFF_ALLMULTI || br->dev.mc_list != NULL)) {
struct sk_buff *skb2;
skb2 = skb_clone(skb, GFP_ATOMIC);
if (skb2) {
passedup = 1;
br_pass_frame_up(br, skb2);
}
}
if (br->stp_enabled &&
!memcmp(dest, bridge_ula, 5) &&
!(dest[5] & 0xF0))
goto handle_special_frame;
if (p->state == BR_STATE_LEARNING ||
p->state == BR_STATE_FORWARDING)
br_fdb_insert(br, p, skb->mac.ethernet->h_source, 0);
if (p->state != BR_STATE_FORWARDING)
goto freeandout;
if (dest[0] & 1) {
br_flood_forward(br, skb, 1);
if (!passedup)
br_pass_frame_up(br, skb);
else
kfree_skb(skb);
return;
}
dst = br_fdb_get(br, dest);
if (dst != NULL && dst->is_local) {
if (!passedup)
br_pass_frame_up(br, skb);
else
kfree_skb(skb);
br_fdb_put(dst);
return;
}
if (dst != NULL) {
br_forward(dst->dst, skb);
br_fdb_put(dst);
return;
}
br_flood_forward(br, skb, 0);
return;
handle_special_frame:
if (!dest[5]) {
br_stp_handle_bpdu(skb);
return;
}
freeandout:
kfree_skb(skb);
}
static int br_handle_frame_finish(struct sk_buff *skb)
{
struct net_bridge *br;
br = skb->dev->br_port->br;
read_lock(&br->lock);
__br_handle_frame(skb);
read_unlock(&br->lock);
return 0;
}
void br_handle_frame(struct sk_buff *skb)
{
NF_HOOK(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
br_handle_frame_finish);
}
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