2e4e6a17af
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>
97 lines
2.1 KiB
C
97 lines
2.1 KiB
C
/* Kernel module to match connection tracking information. */
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/* (C) 1999-2001 Paul `Rusty' Russell
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* (C) 2002-2005 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 <net/netfilter/nf_conntrack_compat.h>
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#include <linux/netfilter/x_tables.h>
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#include <linux/netfilter/xt_state.h>
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>");
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MODULE_DESCRIPTION("ip[6]_tables connection tracking state match module");
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MODULE_ALIAS("ipt_state");
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MODULE_ALIAS("ip6t_state");
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static int
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match(const struct sk_buff *skb,
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const struct net_device *in,
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const struct net_device *out,
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const void *matchinfo,
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int offset,
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unsigned int protoff,
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int *hotdrop)
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{
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const struct xt_state_info *sinfo = matchinfo;
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enum ip_conntrack_info ctinfo;
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unsigned int statebit;
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if (nf_ct_is_untracked(skb))
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statebit = XT_STATE_UNTRACKED;
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else if (!nf_ct_get_ctinfo(skb, &ctinfo))
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statebit = XT_STATE_INVALID;
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else
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statebit = XT_STATE_BIT(ctinfo);
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return (sinfo->statemask & statebit);
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}
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static int check(const char *tablename,
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const void *ip,
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void *matchinfo,
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unsigned int matchsize,
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unsigned int hook_mask)
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{
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if (matchsize != XT_ALIGN(sizeof(struct xt_state_info)))
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return 0;
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return 1;
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}
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static struct xt_match state_match = {
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.name = "state",
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.match = &match,
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.checkentry = &check,
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.me = THIS_MODULE,
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};
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static struct xt_match state6_match = {
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.name = "state",
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.match = &match,
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.checkentry = &check,
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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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int ret;
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need_conntrack();
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ret = xt_register_match(AF_INET, &state_match);
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if (ret < 0)
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return ret;
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ret = xt_register_match(AF_INET6, &state6_match);
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if (ret < 0)
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xt_unregister_match(AF_INET,&state_match);
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return ret;
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}
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static void __exit fini(void)
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{
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xt_unregister_match(AF_INET, &state_match);
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xt_unregister_match(AF_INET6, &state6_match);
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}
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module_init(init);
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module_exit(fini);
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