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/*
* ebt_vlan kernelspace
*
* Authors:
* Bart De Schuymer <bart.de.schuymer@pandora.be>
* Nick Fedchik <nick@fedchik.org.ua>
*
* June, 2002
*/
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_vlan.h>
#include <linux/if_vlan.h>
#include <linux/if_ether.h>
#include <linux/module.h>
static unsigned char debug;
MODULE_PARM (debug, "0-1b");
MODULE_PARM_DESC (debug, "debug=1 is turn on debug messages");
#define MODULE_VERSION "0.2"
static int ebt_filter_vlan (const struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
const void *data,
unsigned int datalen,
const struct ebt_counter *c)
{
struct ebt_vlan_info *infostuff = (struct ebt_vlan_info *) data;
struct vlan_ethhdr *vlanethhdr =
(struct vlan_ethhdr *) skb->mac.raw;
unsigned short v_id;
unsigned short v_prio;
unsigned short v_TCI;
/*
* Calculate 802.1Q VLAN ID and user_priority from
* Tag Control Information (TCI) field.
* Reserved one bit (13) for CFI (Canonical Format Indicator)
*/
v_TCI = ntohs (vlanethhdr->h_vlan_TCI);
v_id = v_TCI & 0xFFF;
v_prio = v_TCI >> 13;
/*
* Checking VLANs
*/
if (infostuff->bitmask & EBT_VLAN_ID) { /* Is VLAN ID parsed? */
if (!((infostuff->id == v_id)
^ !!(infostuff->invflags & EBT_VLAN_ID)))
return 1;
if (debug)
printk (KERN_DEBUG
"ebt_vlan: matched ID=%s%d (mask=%X)\n",
(infostuff->
invflags & EBT_VLAN_ID) ? "!" : "",
infostuff->id, infostuff->bitmask);
}
/*
* Checking User Priority
*/
if (infostuff->bitmask & EBT_VLAN_PRIO) { /* Is VLAN Prio parsed? */
if (!((infostuff->prio == v_prio)
^ !!(infostuff->invflags & EBT_VLAN_PRIO)))
return 1; /* missed */
if (debug)
printk (KERN_DEBUG
"ebt_vlan: matched Prio=%s%d (mask=%X)\n",
(infostuff->
invflags & EBT_VLAN_PRIO) ? "!" : "",
infostuff->prio, infostuff->bitmask);
}
/*
* Checking for Encapsulated proto
*/
if (infostuff->bitmask & EBT_VLAN_ENCAP) { /* Is VLAN Encap parsed? */
if (!
((infostuff->encap ==
vlanethhdr->h_vlan_encapsulated_proto)
^ !!(infostuff->invflags & EBT_VLAN_ENCAP)))
return 1; /* missed */
if (debug)
printk (KERN_DEBUG
"ebt_vlan: matched encap=%s%2.4X (mask=%X)\n",
(infostuff->
invflags & EBT_VLAN_ENCAP) ? "!" : "",
ntohs (infostuff->encap),
infostuff->bitmask);
}
/*
* rule matched
*/
return 0;
}
/*
* ebt_vlan_check() is called when userspace delivers the table to the kernel,
* * it is called to check that userspace doesn't give a bad table.
*/
static int ebt_vlan_check (const char *tablename, unsigned int hooknr,
const struct ebt_entry *e, void *data,
unsigned int datalen)
{
struct ebt_vlan_info *infostuff = (struct ebt_vlan_info *) data;
if (datalen != sizeof (struct ebt_vlan_info))
return -EINVAL;
if (e->ethproto != __constant_htons (ETH_P_8021Q))
return -EINVAL;
if (infostuff->bitmask & ~EBT_VLAN_MASK) {
return -EINVAL;
}
return 0;
}
static struct ebt_match filter_vlan = {
{NULL, NULL},
EBT_VLAN_MATCH,
ebt_filter_vlan,
ebt_vlan_check,
NULL,
THIS_MODULE
};
static int __init init (void)
{
printk (KERN_INFO
"ebt_vlan: 802.1Q VLAN matching module for EBTables "
MODULE_VERSION "\n");
if (debug)
printk (KERN_DEBUG
"ebt_vlan: 802.1Q rule matching debug is on\n");
return ebt_register_match (&filter_vlan);
}
static void __exit fini (void)
{
ebt_unregister_match (&filter_vlan);
}
module_init (init);
module_exit (fini);
EXPORT_NO_SYMBOLS;
MODULE_AUTHOR ("Nick Fedchik <nick@fedchik.org.ua>");
MODULE_DESCRIPTION ("802.1Q VLAN matching module for ebtables, v"
MODULE_VERSION);
MODULE_LICENSE ("GPL");
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