2019-06-04 08:11:33 +00:00
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// SPDX-License-Identifier: GPL-2.0-only
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2005-04-16 22:20:36 +00:00
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/* iptables module to match on related connections */
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/*
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* (C) 2001 Martin Josefsson <gandalf@wlug.westbo.se>
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*/
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2010-03-17 15:04:40 +00:00
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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2005-04-16 22:20:36 +00:00
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#include <linux/module.h>
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#include <linux/skbuff.h>
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#include <linux/netfilter.h>
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_core.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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[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
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#include <linux/netfilter/x_tables.h>
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#include <linux/netfilter/xt_helper.h>
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2005-04-16 22:20:36 +00:00
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Martin Josefsson <gandalf@netfilter.org>");
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2008-01-15 07:42:28 +00:00
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MODULE_DESCRIPTION("Xtables: Related connection matching");
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[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
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MODULE_ALIAS("ipt_helper");
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MODULE_ALIAS("ip6t_helper");
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2005-04-16 22:20:36 +00:00
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2007-07-08 05:15:35 +00:00
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static bool
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2009-07-07 18:42:08 +00:00
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helper_mt(const struct sk_buff *skb, struct xt_action_param *par)
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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{
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2008-10-08 09:35:18 +00:00
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const struct xt_helper_info *info = par->matchinfo;
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2007-07-08 05:16:55 +00:00
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const struct nf_conn *ct;
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const struct nf_conn_help *master_help;
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2007-07-08 05:39:16 +00:00
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const struct nf_conntrack_helper *helper;
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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enum ip_conntrack_info ctinfo;
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2007-07-08 05:15:35 +00:00
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bool ret = info->invert;
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2007-02-12 19:15:49 +00:00
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2007-07-08 05:16:55 +00:00
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ct = nf_ct_get(skb, &ctinfo);
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2007-07-08 05:39:16 +00:00
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if (!ct || !ct->master)
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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return ret;
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2006-03-21 01:56:32 +00:00
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master_help = nfct_help(ct->master);
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2007-07-08 05:39:16 +00:00
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if (!master_help)
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return ret;
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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2016-09-21 15:35:04 +00:00
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/* rcu_read_lock()ed by nf_hook_thresh */
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2007-07-08 05:39:16 +00:00
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helper = rcu_dereference(master_help->helper);
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if (!helper)
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return ret;
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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if (info->name[0] == '\0')
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2007-07-08 05:15:35 +00:00
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ret = !ret;
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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else
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2008-01-11 06:41:28 +00:00
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ret ^= !strncmp(helper->name, info->name,
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strlen(helper->name));
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[NETFILTER]: Add nf_conntrack subsystem.
The existing connection tracking subsystem in netfilter can only
handle ipv4. There were basically two choices present to add
connection tracking support for ipv6. We could either duplicate all
of the ipv4 connection tracking code into an ipv6 counterpart, or (the
choice taken by these patches) we could design a generic layer that
could handle both ipv4 and ipv6 and thus requiring only one sub-protocol
(TCP, UDP, etc.) connection tracking helper module to be written.
In fact nf_conntrack is capable of working with any layer 3
protocol.
The existing ipv4 specific conntrack code could also not deal
with the pecularities of doing connection tracking on ipv6,
which is also cured here. For example, these issues include:
1) ICMPv6 handling, which is used for neighbour discovery in
ipv6 thus some messages such as these should not participate
in connection tracking since effectively they are like ARP
messages
2) fragmentation must be handled differently in ipv6, because
the simplistic "defrag, connection track and NAT, refrag"
(which the existing ipv4 connection tracking does) approach simply
isn't feasible in ipv6
3) ipv6 extension header parsing must occur at the correct spots
before and after connection tracking decisions, and there were
no provisions for this in the existing connection tracking
design
4) ipv6 has no need for stateful NAT
The ipv4 specific conntrack layer is kept around, until all of
the ipv4 specific conntrack helpers are ported over to nf_conntrack
and it is feature complete. Once that occurs, the old conntrack
stuff will get placed into the feature-removal-schedule and we will
fully kill it off 6 months later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2005-11-10 00:38:16 +00:00
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return ret;
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}
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2010-03-19 16:16:42 +00:00
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static int helper_mt_check(const struct xt_mtchk_param *par)
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2005-04-16 22:20:36 +00:00
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{
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2008-10-08 09:35:18 +00:00
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struct xt_helper_info *info = par->matchinfo;
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2010-03-19 16:32:59 +00:00
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int ret;
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2005-04-16 22:20:36 +00:00
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2016-11-15 20:36:40 +00:00
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ret = nf_ct_netns_get(par->net, par->family);
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2010-03-19 16:32:59 +00:00
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if (ret < 0) {
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2018-02-09 14:52:07 +00:00
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pr_info_ratelimited("cannot load conntrack support for proto=%u\n",
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par->family);
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2010-03-19 16:32:59 +00:00
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return ret;
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2006-03-22 21:56:08 +00:00
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}
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2016-09-20 02:31:04 +00:00
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info->name[sizeof(info->name) - 1] = '\0';
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2010-03-23 15:35:56 +00:00
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return 0;
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2005-04-16 22:20:36 +00:00
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}
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2008-10-08 09:35:19 +00:00
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static void helper_mt_destroy(const struct xt_mtdtor_param *par)
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2006-03-22 21:56:08 +00:00
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{
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2016-11-15 20:36:40 +00:00
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nf_ct_netns_put(par->net, par->family);
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2006-03-22 21:56:08 +00:00
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}
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2008-10-08 09:35:20 +00:00
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static struct xt_match helper_mt_reg __read_mostly = {
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.name = "helper",
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.revision = 0,
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.family = NFPROTO_UNSPEC,
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.checkentry = helper_mt_check,
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.match = helper_mt,
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.destroy = helper_mt_destroy,
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.matchsize = sizeof(struct xt_helper_info),
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.me = THIS_MODULE,
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2005-04-16 22:20:36 +00:00
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};
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2007-12-05 07:24:03 +00:00
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static int __init helper_mt_init(void)
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2005-04-16 22:20:36 +00:00
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{
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2008-10-08 09:35:20 +00:00
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return xt_register_match(&helper_mt_reg);
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2005-04-16 22:20:36 +00:00
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}
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2007-12-05 07:24:03 +00:00
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static void __exit helper_mt_exit(void)
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2005-04-16 22:20:36 +00:00
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{
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2008-10-08 09:35:20 +00:00
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xt_unregister_match(&helper_mt_reg);
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2005-04-16 22:20:36 +00:00
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}
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2007-12-05 07:24:03 +00:00
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module_init(helper_mt_init);
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module_exit(helper_mt_exit);
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