![Harald Welte](/assets/img/avatar_default.png)
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>
105 lines
2.6 KiB
C
105 lines
2.6 KiB
C
/* This is a module which is used for setting the TOS field of a packet. */
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/* (C) 1999-2001 Paul `Rusty' Russell
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* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/module.h>
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#include <linux/skbuff.h>
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#include <linux/ip.h>
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#include <net/checksum.h>
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#include <linux/netfilter_ipv4/ip_tables.h>
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#include <linux/netfilter_ipv4/ipt_TOS.h>
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
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MODULE_DESCRIPTION("iptables TOS mangling module");
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static unsigned int
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target(struct sk_buff **pskb,
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const struct net_device *in,
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const struct net_device *out,
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unsigned int hooknum,
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const void *targinfo,
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void *userinfo)
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{
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const struct ipt_tos_target_info *tosinfo = targinfo;
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if (((*pskb)->nh.iph->tos & IPTOS_TOS_MASK) != tosinfo->tos) {
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u_int16_t diffs[2];
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if (!skb_make_writable(pskb, sizeof(struct iphdr)))
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return NF_DROP;
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diffs[0] = htons((*pskb)->nh.iph->tos) ^ 0xFFFF;
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(*pskb)->nh.iph->tos
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= ((*pskb)->nh.iph->tos & IPTOS_PREC_MASK)
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diffs[1] = htons((*pskb)->nh.iph->tos);
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(*pskb)->nh.iph->check
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= csum_fold(csum_partial((char *)diffs,
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sizeof(diffs),
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(*pskb)->nh.iph->check
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^0xFFFF));
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}
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return IPT_CONTINUE;
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}
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static int
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checkentry(const char *tablename,
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const void *e_void,
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void *targinfo,
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unsigned int targinfosize,
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unsigned int hook_mask)
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{
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const u_int8_t tos = ((struct ipt_tos_target_info *)targinfo)->tos;
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if (targinfosize != IPT_ALIGN(sizeof(struct ipt_tos_target_info))) {
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printk(KERN_WARNING "TOS: targinfosize %u != %Zu\n",
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targinfosize,
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IPT_ALIGN(sizeof(struct ipt_tos_target_info)));
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return 0;
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}
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if (strcmp(tablename, "mangle") != 0) {
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printk(KERN_WARNING "TOS: can only be called from \"mangle\" table, not \"%s\"\n", tablename);
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return 0;
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}
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if (tos != IPTOS_LOWDELAY
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&& tos != IPTOS_THROUGHPUT
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&& tos != IPTOS_RELIABILITY
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&& tos != IPTOS_MINCOST
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&& tos != IPTOS_NORMALSVC) {
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printk(KERN_WARNING "TOS: bad tos value %#x\n", tos);
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return 0;
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}
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return 1;
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}
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static struct ipt_target ipt_tos_reg = {
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.name = "TOS",
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.target = target,
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.checkentry = checkentry,
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.me = THIS_MODULE,
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};
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static int __init init(void)
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{
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return ipt_register_target(&ipt_tos_reg);
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}
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static void __exit fini(void)
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{
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ipt_unregister_target(&ipt_tos_reg);
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}
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module_init(init);
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module_exit(fini);
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