1 /* This is a module which is used for setting the TOS field of a packet. */
3 /* (C) 1999-2001 Paul `Rusty' Russell
4 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/module.h>
12 #include <linux/skbuff.h>
14 #include <net/checksum.h>
16 #include <linux/netfilter_ipv4/ip_tables.h>
17 #include <linux/netfilter_ipv4/ipt_TOS.h>
19 MODULE_LICENSE("GPL");
20 MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
21 MODULE_DESCRIPTION("iptables TOS mangling module");
24 target(struct sk_buff
**pskb
,
25 const struct net_device
*in
,
26 const struct net_device
*out
,
28 const struct xt_target
*target
,
31 const struct ipt_tos_target_info
*tosinfo
= targinfo
;
32 struct iphdr
*iph
= (*pskb
)->nh
.iph
;
34 if ((iph
->tos
& IPTOS_TOS_MASK
) != tosinfo
->tos
) {
36 if (!skb_make_writable(pskb
, sizeof(struct iphdr
)))
38 iph
= (*pskb
)->nh
.iph
;
40 iph
->tos
= (iph
->tos
& IPTOS_PREC_MASK
) | tosinfo
->tos
;
41 nf_csum_replace2(&iph
->check
, htons(oldtos
), htons(iph
->tos
));
47 checkentry(const char *tablename
,
49 const struct xt_target
*target
,
51 unsigned int hook_mask
)
53 const u_int8_t tos
= ((struct ipt_tos_target_info
*)targinfo
)->tos
;
55 if (tos
!= IPTOS_LOWDELAY
56 && tos
!= IPTOS_THROUGHPUT
57 && tos
!= IPTOS_RELIABILITY
58 && tos
!= IPTOS_MINCOST
59 && tos
!= IPTOS_NORMALSVC
) {
60 printk(KERN_WARNING
"TOS: bad tos value %#x\n", tos
);
66 static struct ipt_target ipt_tos_reg
= {
69 .targetsize
= sizeof(struct ipt_tos_target_info
),
71 .checkentry
= checkentry
,
75 static int __init
ipt_tos_init(void)
77 return ipt_register_target(&ipt_tos_reg
);
80 static void __exit
ipt_tos_fini(void)
82 ipt_unregister_target(&ipt_tos_reg
);
85 module_init(ipt_tos_init
);
86 module_exit(ipt_tos_fini
);