2005-04-16 22:20:36 +00:00
|
|
|
/* ipv6header match - matches IPv6 packets based
|
|
|
|
on whether they contain certain headers */
|
|
|
|
|
|
|
|
/* Original idea: Brad Chapman
|
|
|
|
* Rewritten by: Andras Kis-Szabo <kisza@sch.bme.hu> */
|
|
|
|
|
|
|
|
/* (C) 2001-2002 Andras Kis-Szabo <kisza@sch.bme.hu>
|
|
|
|
*
|
|
|
|
* This program is free software; you can redistribute it and/or modify
|
|
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
|
|
* published by the Free Software Foundation.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/skbuff.h>
|
|
|
|
#include <linux/ipv6.h>
|
|
|
|
#include <linux/types.h>
|
|
|
|
#include <net/checksum.h>
|
|
|
|
#include <net/ipv6.h>
|
|
|
|
|
|
|
|
#include <linux/netfilter_ipv6/ip6_tables.h>
|
|
|
|
#include <linux/netfilter_ipv6/ip6t_ipv6header.h>
|
|
|
|
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
MODULE_DESCRIPTION("IPv6 headers match");
|
|
|
|
MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>");
|
|
|
|
|
|
|
|
static int
|
|
|
|
ipv6header_match(const struct sk_buff *skb,
|
|
|
|
const struct net_device *in,
|
|
|
|
const struct net_device *out,
|
|
|
|
const void *matchinfo,
|
|
|
|
int offset,
|
|
|
|
unsigned int protoff,
|
|
|
|
int *hotdrop)
|
|
|
|
{
|
|
|
|
const struct ip6t_ipv6header_info *info = matchinfo;
|
|
|
|
unsigned int temp;
|
|
|
|
int len;
|
|
|
|
u8 nexthdr;
|
|
|
|
unsigned int ptr;
|
|
|
|
|
|
|
|
/* Make sure this isn't an evil packet */
|
|
|
|
|
|
|
|
/* type of the 1st exthdr */
|
|
|
|
nexthdr = skb->nh.ipv6h->nexthdr;
|
|
|
|
/* pointer to the 1st exthdr */
|
|
|
|
ptr = sizeof(struct ipv6hdr);
|
|
|
|
/* available length */
|
|
|
|
len = skb->len - ptr;
|
|
|
|
temp = 0;
|
|
|
|
|
2006-01-17 10:39:39 +00:00
|
|
|
while (ip6t_ext_hdr(nexthdr)) {
|
2005-04-16 22:20:36 +00:00
|
|
|
struct ipv6_opt_hdr _hdr, *hp;
|
2006-01-17 10:39:39 +00:00
|
|
|
int hdrlen;
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* Is there enough space for the next ext header? */
|
2006-01-17 10:39:39 +00:00
|
|
|
if (len < (int)sizeof(struct ipv6_opt_hdr))
|
|
|
|
return 0;
|
2005-04-16 22:20:36 +00:00
|
|
|
/* No more exthdr -> evaluate */
|
2006-01-17 10:39:39 +00:00
|
|
|
if (nexthdr == NEXTHDR_NONE) {
|
2005-04-16 22:20:36 +00:00
|
|
|
temp |= MASK_NONE;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
/* ESP -> evaluate */
|
2006-01-17 10:39:39 +00:00
|
|
|
if (nexthdr == NEXTHDR_ESP) {
|
2005-04-16 22:20:36 +00:00
|
|
|
temp |= MASK_ESP;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
|
|
|
|
BUG_ON(hp == NULL);
|
|
|
|
|
|
|
|
/* Calculate the header length */
|
2006-01-17 10:39:39 +00:00
|
|
|
if (nexthdr == NEXTHDR_FRAGMENT) {
|
|
|
|
hdrlen = 8;
|
|
|
|
} else if (nexthdr == NEXTHDR_AUTH)
|
|
|
|
hdrlen = (hp->hdrlen + 2) << 2;
|
|
|
|
else
|
|
|
|
hdrlen = ipv6_optlen(hp);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* set the flag */
|
2006-01-17 10:39:39 +00:00
|
|
|
switch (nexthdr) {
|
|
|
|
case NEXTHDR_HOP:
|
|
|
|
temp |= MASK_HOPOPTS;
|
|
|
|
break;
|
|
|
|
case NEXTHDR_ROUTING:
|
|
|
|
temp |= MASK_ROUTING;
|
|
|
|
break;
|
|
|
|
case NEXTHDR_FRAGMENT:
|
|
|
|
temp |= MASK_FRAGMENT;
|
|
|
|
break;
|
|
|
|
case NEXTHDR_AUTH:
|
|
|
|
temp |= MASK_AH;
|
|
|
|
break;
|
|
|
|
case NEXTHDR_DEST:
|
|
|
|
temp |= MASK_DSTOPTS;
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
return 0;
|
|
|
|
break;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2006-01-17 10:39:39 +00:00
|
|
|
nexthdr = hp->nexthdr;
|
|
|
|
len -= hdrlen;
|
|
|
|
ptr += hdrlen;
|
2005-04-16 22:20:36 +00:00
|
|
|
if (ptr > skb->len)
|
|
|
|
break;
|
2006-01-17 10:39:39 +00:00
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2006-01-17 10:39:39 +00:00
|
|
|
if ((nexthdr != NEXTHDR_NONE) && (nexthdr != NEXTHDR_ESP))
|
2005-04-16 22:20:36 +00:00
|
|
|
temp |= MASK_PROTO;
|
|
|
|
|
|
|
|
if (info->modeflag)
|
|
|
|
return !((temp ^ info->matchflags ^ info->invflags)
|
|
|
|
& info->matchflags);
|
|
|
|
else {
|
|
|
|
if (info->invflags)
|
|
|
|
return temp != info->matchflags;
|
|
|
|
else
|
|
|
|
return temp == info->matchflags;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
ipv6header_checkentry(const char *tablename,
|
[NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables
This monster-patch tries to do the best job for unifying the data
structures and backend interfaces for the three evil clones ip_tables,
ip6_tables and arp_tables. In an ideal world we would never have
allowed this kind of copy+paste programming... but well, our world
isn't (yet?) ideal.
o introduce a new x_tables module
o {ip,arp,ip6}_tables depend on this x_tables module
o registration functions for tables, matches and targets are only
wrappers around x_tables provided functions
o all matches/targets that are used from ip_tables and ip6_tables
are now implemented as xt_FOOBAR.c files and provide module aliases
to ipt_FOOBAR and ip6t_FOOBAR
o header files for xt_matches are in include/linux/netfilter/,
include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers
around the xt_FOOBAR.h headers
Based on this patchset we're going to further unify the code,
gradually getting rid of all the layer 3 specific assumptions.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-12 21:30:04 +00:00
|
|
|
const void *ip,
|
2005-04-16 22:20:36 +00:00
|
|
|
void *matchinfo,
|
|
|
|
unsigned int matchsize,
|
|
|
|
unsigned int hook_mask)
|
|
|
|
{
|
|
|
|
const struct ip6t_ipv6header_info *info = matchinfo;
|
|
|
|
|
|
|
|
/* Check for obvious errors */
|
|
|
|
/* This match is valid in all hooks! */
|
|
|
|
if (matchsize != IP6T_ALIGN(sizeof(struct ip6t_ipv6header_info)))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/* invflags is 0 or 0xff in hard mode */
|
2006-01-17 10:39:39 +00:00
|
|
|
if ((!info->modeflag) && info->invflags != 0x00 &&
|
|
|
|
info->invflags != 0xFF)
|
2005-04-16 22:20:36 +00:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct ip6t_match ip6t_ipv6header_match = {
|
|
|
|
.name = "ipv6header",
|
|
|
|
.match = &ipv6header_match,
|
|
|
|
.checkentry = &ipv6header_checkentry,
|
|
|
|
.destroy = NULL,
|
|
|
|
.me = THIS_MODULE,
|
|
|
|
};
|
|
|
|
|
2006-01-17 10:39:39 +00:00
|
|
|
static int __init ipv6header_init(void)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
|
|
|
return ip6t_register_match(&ip6t_ipv6header_match);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __exit ipv6header_exit(void)
|
|
|
|
{
|
|
|
|
ip6t_unregister_match(&ip6t_ipv6header_match);
|
|
|
|
}
|
|
|
|
|
|
|
|
module_init(ipv6header_init);
|
|
|
|
module_exit(ipv6header_exit);
|