alistair23-linux/net/bridge/br_device.c
Herbert Xu 576a30eb64 [NET]: Added GSO header verification
When GSO packets come from an untrusted source (e.g., a Xen guest domain),
we need to verify the header integrity before passing it to the hardware.

Since the first step in GSO is to verify the header, we can reuse that
code by adding a new bit to gso_type: SKB_GSO_DODGY.  Packets with this
bit set can only be fed directly to devices with the corresponding bit
NETIF_F_GSO_ROBUST.  If the device doesn't have that bit, then the skb
is fed to the GSO engine which will allow the packet to be sent to the
hardware if it passes the header check.

This patch changes the sg flag to a full features flag.  The same method
can be used to implement TSO ECN support.  We simply have to mark packets
with CWR set with SKB_GSO_ECN so that only hardware with a corresponding
NETIF_F_TSO_ECN can accept them.  The GSO engine can either fully segment
the packet, or segment the first MTU and pass the rest to the hardware for
further segmentation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29 16:57:53 -07:00

190 lines
4.2 KiB
C

/*
* Device handling code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* $Id: br_device.c,v 1.6 2001/12/24 00:59:55 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/ethtool.h>
#include <asm/uaccess.h>
#include "br_private.h"
static struct net_device_stats *br_dev_get_stats(struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
return &br->statistics;
}
/* net device transmit always called with no BH (preempt_disabled) */
int br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
const unsigned char *dest = skb->data;
struct net_bridge_fdb_entry *dst;
br->statistics.tx_packets++;
br->statistics.tx_bytes += skb->len;
skb->mac.raw = skb->data;
skb_pull(skb, ETH_HLEN);
if (dest[0] & 1)
br_flood_deliver(br, skb, 0);
else if ((dst = __br_fdb_get(br, dest)) != NULL)
br_deliver(dst->dst, skb);
else
br_flood_deliver(br, skb, 0);
return 0;
}
static int br_dev_open(struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
br_features_recompute(br);
netif_start_queue(dev);
br_stp_enable_bridge(br);
return 0;
}
static void br_dev_set_multicast_list(struct net_device *dev)
{
}
static int br_dev_stop(struct net_device *dev)
{
br_stp_disable_bridge(netdev_priv(dev));
netif_stop_queue(dev);
return 0;
}
static int br_change_mtu(struct net_device *dev, int new_mtu)
{
if (new_mtu < 68 || new_mtu > br_min_mtu(netdev_priv(dev)))
return -EINVAL;
dev->mtu = new_mtu;
return 0;
}
/* Allow setting mac address of pseudo-bridge to be same as
* any of the bound interfaces
*/
static int br_set_mac_address(struct net_device *dev, void *p)
{
struct net_bridge *br = netdev_priv(dev);
struct sockaddr *addr = p;
struct net_bridge_port *port;
int err = -EADDRNOTAVAIL;
spin_lock_bh(&br->lock);
list_for_each_entry(port, &br->port_list, list) {
if (!compare_ether_addr(port->dev->dev_addr, addr->sa_data)) {
br_stp_change_bridge_id(br, addr->sa_data);
err = 0;
break;
}
}
spin_unlock_bh(&br->lock);
return err;
}
static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
{
strcpy(info->driver, "bridge");
strcpy(info->version, BR_VERSION);
strcpy(info->fw_version, "N/A");
strcpy(info->bus_info, "N/A");
}
static int br_set_sg(struct net_device *dev, u32 data)
{
struct net_bridge *br = netdev_priv(dev);
if (data)
br->feature_mask |= NETIF_F_SG;
else
br->feature_mask &= ~NETIF_F_SG;
br_features_recompute(br);
return 0;
}
static int br_set_tso(struct net_device *dev, u32 data)
{
struct net_bridge *br = netdev_priv(dev);
if (data)
br->feature_mask |= NETIF_F_TSO;
else
br->feature_mask &= ~NETIF_F_TSO;
br_features_recompute(br);
return 0;
}
static int br_set_tx_csum(struct net_device *dev, u32 data)
{
struct net_bridge *br = netdev_priv(dev);
if (data)
br->feature_mask |= NETIF_F_NO_CSUM;
else
br->feature_mask &= ~NETIF_F_ALL_CSUM;
br_features_recompute(br);
return 0;
}
static struct ethtool_ops br_ethtool_ops = {
.get_drvinfo = br_getinfo,
.get_link = ethtool_op_get_link,
.get_sg = ethtool_op_get_sg,
.set_sg = br_set_sg,
.get_tx_csum = ethtool_op_get_tx_csum,
.set_tx_csum = br_set_tx_csum,
.get_tso = ethtool_op_get_tso,
.set_tso = br_set_tso,
};
void br_dev_setup(struct net_device *dev)
{
memset(dev->dev_addr, 0, ETH_ALEN);
ether_setup(dev);
dev->do_ioctl = br_dev_ioctl;
dev->get_stats = br_dev_get_stats;
dev->hard_start_xmit = br_dev_xmit;
dev->open = br_dev_open;
dev->set_multicast_list = br_dev_set_multicast_list;
dev->change_mtu = br_change_mtu;
dev->destructor = free_netdev;
SET_MODULE_OWNER(dev);
SET_ETHTOOL_OPS(dev, &br_ethtool_ops);
dev->stop = br_dev_stop;
dev->tx_queue_len = 0;
dev->set_mac_address = br_set_mac_address;
dev->priv_flags = IFF_EBRIDGE;
dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
NETIF_F_TSO | NETIF_F_NO_CSUM | NETIF_F_GSO_ROBUST;
}