2007-02-07 23:12:57 +00:00
|
|
|
/*
|
|
|
|
* Copyright (C)2006 USAGI/WIDE Project
|
|
|
|
*
|
|
|
|
* 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.
|
|
|
|
*
|
|
|
|
* Author:
|
|
|
|
* Masahide NAKAMURA @USAGI <masahide.nakamura.cz@hitachi.com>
|
|
|
|
*
|
|
|
|
* Based on net/netfilter/xt_tcpudp.c
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <net/ip.h>
|
|
|
|
#include <linux/ipv6.h>
|
|
|
|
#include <net/ipv6.h>
|
|
|
|
#include <net/mip6.h>
|
|
|
|
|
|
|
|
#include <linux/netfilter/x_tables.h>
|
|
|
|
#include <linux/netfilter_ipv6/ip6t_mh.h>
|
|
|
|
|
2008-01-15 07:42:28 +00:00
|
|
|
MODULE_DESCRIPTION("Xtables: IPv6 Mobility Header match");
|
2007-02-07 23:12:57 +00:00
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
|
|
|
|
#ifdef DEBUG_IP_FIREWALL_USER
|
|
|
|
#define duprintf(format, args...) printk(format , ## args)
|
|
|
|
#else
|
|
|
|
#define duprintf(format, args...)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* Returns 1 if the type is matched by the range, 0 otherwise */
|
2007-07-08 05:15:35 +00:00
|
|
|
static inline bool
|
|
|
|
type_match(u_int8_t min, u_int8_t max, u_int8_t type, bool invert)
|
2007-02-07 23:12:57 +00:00
|
|
|
{
|
2007-07-08 05:15:35 +00:00
|
|
|
return (type >= min && type <= max) ^ invert;
|
2007-02-07 23:12:57 +00:00
|
|
|
}
|
|
|
|
|
2008-10-08 09:35:18 +00:00
|
|
|
static bool mh_mt6(const struct sk_buff *skb, const struct xt_match_param *par)
|
2007-02-07 23:12:57 +00:00
|
|
|
{
|
2007-07-08 05:16:55 +00:00
|
|
|
struct ip6_mh _mh;
|
|
|
|
const struct ip6_mh *mh;
|
2008-10-08 09:35:18 +00:00
|
|
|
const struct ip6t_mh *mhinfo = par->matchinfo;
|
2007-02-07 23:12:57 +00:00
|
|
|
|
|
|
|
/* Must not be a fragment. */
|
2008-10-08 09:35:18 +00:00
|
|
|
if (par->fragoff != 0)
|
2007-07-08 05:15:35 +00:00
|
|
|
return false;
|
2007-02-07 23:12:57 +00:00
|
|
|
|
2008-10-08 09:35:18 +00:00
|
|
|
mh = skb_header_pointer(skb, par->thoff, sizeof(_mh), &_mh);
|
2007-02-07 23:12:57 +00:00
|
|
|
if (mh == NULL) {
|
|
|
|
/* We've been asked to examine this packet, and we
|
|
|
|
can't. Hence, no choice but to drop. */
|
|
|
|
duprintf("Dropping evil MH tinygram.\n");
|
2008-10-08 09:35:18 +00:00
|
|
|
*par->hotdrop = true;
|
2007-07-08 05:15:35 +00:00
|
|
|
return false;
|
2007-02-07 23:12:57 +00:00
|
|
|
}
|
|
|
|
|
2007-02-12 19:16:17 +00:00
|
|
|
if (mh->ip6mh_proto != IPPROTO_NONE) {
|
|
|
|
duprintf("Dropping invalid MH Payload Proto: %u\n",
|
|
|
|
mh->ip6mh_proto);
|
2008-10-08 09:35:18 +00:00
|
|
|
*par->hotdrop = true;
|
2007-07-08 05:15:35 +00:00
|
|
|
return false;
|
2007-02-12 19:16:17 +00:00
|
|
|
}
|
|
|
|
|
2007-02-07 23:12:57 +00:00
|
|
|
return type_match(mhinfo->types[0], mhinfo->types[1], mh->ip6mh_type,
|
|
|
|
!!(mhinfo->invflags & IP6T_MH_INV_TYPE));
|
|
|
|
}
|
|
|
|
|
2008-10-08 09:35:18 +00:00
|
|
|
static bool mh_mt6_check(const struct xt_mtchk_param *par)
|
2007-02-07 23:12:57 +00:00
|
|
|
{
|
2008-10-08 09:35:18 +00:00
|
|
|
const struct ip6t_mh *mhinfo = par->matchinfo;
|
2007-02-07 23:12:57 +00:00
|
|
|
|
|
|
|
/* Must specify no unknown invflags */
|
|
|
|
return !(mhinfo->invflags & ~IP6T_MH_INV_MASK);
|
|
|
|
}
|
|
|
|
|
2007-12-05 07:24:03 +00:00
|
|
|
static struct xt_match mh_mt6_reg __read_mostly = {
|
2007-02-07 23:12:57 +00:00
|
|
|
.name = "mh",
|
2008-10-08 09:35:01 +00:00
|
|
|
.family = NFPROTO_IPV6,
|
2007-12-05 07:24:03 +00:00
|
|
|
.checkentry = mh_mt6_check,
|
|
|
|
.match = mh_mt6,
|
2007-02-07 23:12:57 +00:00
|
|
|
.matchsize = sizeof(struct ip6t_mh),
|
|
|
|
.proto = IPPROTO_MH,
|
|
|
|
.me = THIS_MODULE,
|
|
|
|
};
|
|
|
|
|
2007-12-05 07:24:03 +00:00
|
|
|
static int __init mh_mt6_init(void)
|
2007-02-07 23:12:57 +00:00
|
|
|
{
|
2007-12-05 07:24:03 +00:00
|
|
|
return xt_register_match(&mh_mt6_reg);
|
2007-02-07 23:12:57 +00:00
|
|
|
}
|
|
|
|
|
2007-12-05 07:24:03 +00:00
|
|
|
static void __exit mh_mt6_exit(void)
|
2007-02-07 23:12:57 +00:00
|
|
|
{
|
2007-12-05 07:24:03 +00:00
|
|
|
xt_unregister_match(&mh_mt6_reg);
|
2007-02-07 23:12:57 +00:00
|
|
|
}
|
|
|
|
|
2007-12-05 07:24:03 +00:00
|
|
|
module_init(mh_mt6_init);
|
|
|
|
module_exit(mh_mt6_exit);
|