shorewall_code/Shorewall6/manpages/shorewall6-conntrack.xml
Tom Eastep ac6a506e35 Allow logging from the RAW table
Signed-off-by: Tom Eastep <teastep@shorewall.net>
2013-12-31 11:04:43 -08:00

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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
<refentry>
<refmeta>
<refentrytitle>shorewall6-conntrack</refentrytitle>
<manvolnum>5</manvolnum>
</refmeta>
<refnamediv>
<refname>conntrack</refname>
<refpurpose>shorewall6 conntrack file</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>/etc/shorewall6/conntrack</command>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>The original intent of the <emphasis role="bold">notrack</emphasis>
file was to exempt certain traffic from Netfilter connection tracking.
Traffic matching entries in the file were not to be tracked.</para>
<para>The role of the file was expanded in Shorewall 4.4.27 to include all
rules that can be added in the Netfilter <emphasis
role="bold">raw</emphasis> table. In 4.5.7, the file's name was changed to
<emphasis role="bold">conntrack</emphasis>.</para>
<para>The file supports two different column layouts: FORMAT 1, FORMAT 2,
and FORMAT 3, FORMAT 1 being the default. The three differ as
follows:</para>
<itemizedlist>
<listitem>
<para>in FORMAT 2 and 3, there is an additional leading ACTION
column.</para>
</listitem>
<listitem>
<para>in FORMAT 3, the SOURCE column accepts no zone name; rather the
ACTION column allows a SUFFIX that determines the chain(s) that the
generated rule will be added to.</para>
</listitem>
</itemizedlist>
<para>When an entry in the following form is encountered, the format of
the following entries are assumed to be of the specified
<replaceable>format</replaceable>.</para>
<simplelist>
<member><emphasis role="bold">[?]FORMAT</emphasis>
<replaceable>format</replaceable></member>
</simplelist>
<para>where <replaceable>format</replaceable> is either <emphasis
role="bold">1</emphasis>,<emphasis role="bold">2</emphasis> or <emphasis
role="bold">3</emphasis>.</para>
<para>Format 3 was introduced in Shorewall 4.5.10. The optional '?' was
introduced in Shorewall 4.5.11 and ?FORMAT is the preferred form; the form
without the '?' is deprecated.</para>
<para>Comments may be attached to Netfilter rules generated from entries
in this file through the use of COMMENT lines. These lines begin with the
word COMMENT; the remainder of the line is treated as a comment which is
attached to subsequent rules until another COMMENT line is found or until
the end of the file is reached. To stop adding comments to rules, use a
line with only the word COMMENT.</para>
<note>
<para>Beginning with Shorewall 4.5.11, ?COMMENT is a synonym for COMMENT
and is preferred.</para>
</note>
<para>The columns in the file are as follows (where the column name is
followed by a different name in parentheses, the different name is used in
the alternate specification syntax).</para>
<variablelist>
<varlistentry>
<term><emphasis role="bold">ACTION</emphasis> - {<emphasis
role="bold">NOTRACK</emphasis>|<emphasis
role="bold">CT</emphasis>:<emphasis
role="bold">helper</emphasis>:<replaceable>name</replaceable>[(<replaceable>arg</replaceable>=<replaceable>val</replaceable>[,...])|<emphasis
role="bold">CT:notrack</emphasis>|DROP|LOG|NFLOG(<replaceable>nflog-parameters</replaceable>)}[:<replaceable>log-level</replaceable>[:<replaceable>log-tag</replaceable>]][:<replaceable>chain-designator</replaceable>]</term>
<listitem>
<para>This column is only present when FORMAT &gt;= 2. Values other
than NOTRACK require <firstterm>CT Target </firstterm>support in
your iptables and kernel.</para>
<itemizedlist>
<listitem>
<para><option>NOTRACK</option> or
<option>CT:notrack</option></para>
<para>Disables connection tracking for this packet. If a
<replaceable>log-level</replaceable> is specified, the packet
will also be logged at that level.</para>
</listitem>
<listitem>
<para><option>helper</option>:<replaceable>name</replaceable></para>
<para>Attach the helper identified by the
<replaceable>name</replaceable> to this connection. This is more
flexible than loading the conntrack helper with preset ports. If
a <replaceable>log-level</replaceable> is specified, the packet
will also be logged at that level.</para>
<para>At this writing, the available helpers are:</para>
<variablelist>
<varlistentry>
<term>amanda</term>
<listitem>
<para>Requires that the amanda netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>ftp</term>
<listitem>
<para>Requires that the FTP netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>irc</term>
<listitem>
<para>Requires that the IRC netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>netbios-ns</term>
<listitem>
<para>Requires that the netbios_ns (sic) helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>RAS and Q.931</term>
<listitem>
<para>These require that the H323 netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>pptp</term>
<listitem>
<para>Requires that the pptp netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>sane</term>
<listitem>
<para>Requires that the SANE netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>sip</term>
<listitem>
<para>Requires that the SIP netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>snmp</term>
<listitem>
<para>Requires that the SNMP netfilter helper is
present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>tftp</term>
<listitem>
<para>Requires that the TFTP netfilter helper is
present.</para>
</listitem>
</varlistentry>
</variablelist>
<para>May be followed by an option list of
<replaceable>arg</replaceable>=<replaceable>val</replaceable>
pairs in parentheses:</para>
<itemizedlist>
<listitem>
<para><option>ctevents</option>=<replaceable>event</replaceable>[,...]</para>
<para>Only generate the specified conntrack events for this
connection. Possible event types are: <emphasis
role="bold">new</emphasis>, <emphasis
role="bold">related</emphasis>, <emphasis
role="bold">destroy</emphasis>, <emphasis
role="bold">reply</emphasis>, <emphasis
role="bold">assured</emphasis>, <emphasis
role="bold">protoinfo</emphasis>, <emphasis
role="bold">helper</emphasis>, <emphasis
role="bold">mark</emphasis> (this is connection mark, not
packet mark), <emphasis role="bold">natseqinfo</emphasis>,
and <emphasis role="bold">secmark</emphasis>. If more than
one <emphasis>event</emphasis> is listed, the
<replaceable>event</replaceable> list must be enclosed in
parentheses (e.g., ctevents=(new,related)).</para>
</listitem>
<listitem>
<para><option>expevents</option><option>=new</option></para>
<para>Only generate a <emphasis role="bold">new</emphasis>
expectation events for this connection.</para>
</listitem>
</itemizedlist>
</listitem>
<listitem>
<para><option>DROP</option></para>
<para>Added in Shorewall 4.5.10. Silently discard the packet. If
a <replaceable>log-level</replaceable> is specified, the packet
will also be logged at that level.</para>
</listitem>
<listitem>
<para><option>LOG</option></para>
<para>Added in Shoreawll 4.6.0. Logs the packet using the
specified <replaceable>log-level</replaceable> and<replaceable>
log-tag </replaceable>(if any). If no log-level is specified,
then 'info' is assumed.</para>
</listitem>
<listitem>
<para><option>NFLOG</option></para>
<para>Added in Shoreawll 4.6.0. Queues the packet to a backend
logging daemon using the NFLOG netfilter target with the
specified <replaceable>nflog-parameters</replaceable>.</para>
</listitem>
</itemizedlist>
<para>When FORMAT = 1, this column is not present and the rule is
processed as if NOTRACK had been entered in this column.</para>
<para>Beginning with Shorewall 4.5.10, when FORMAT = 3, this column
can end with a colon followed by a
<replaceable>chain-designator</replaceable>. The
<replaceable>chain-designator</replaceable> can be one of the
following:</para>
<variablelist>
<varlistentry>
<term>P</term>
<listitem>
<para>The rule is added to the raw table PREROUTING chain.
This is the default if no
<replaceable>chain-designator</replaceable> is present.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>O</term>
<listitem>
<para>The rule is added to the raw table OUTPUT chain.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>PO or OP</term>
<listitem>
<para>The rule is added to the raw table PREROUTING and OUTPUT
chains.</para>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
<varlistentry>
<term>SOURCE (formats 1 and 2)
<emphasis>zone</emphasis>[:<emphasis>interface</emphasis>][:<emphasis>address-list</emphasis>]</term>
<listitem>
<para>where <replaceable>zone</replaceable> is the name of a zone,
<replaceable>interface</replaceable> is an interface to that zone,
and <replaceable>address-list</replaceable> is a comma-separated
list of addresses (may contain exclusion - see <ulink
url="shorewall-exclusion.html">shorewall6-exclusion</ulink>
(5)).</para>
<para>Beginning with Shorewall 4.5.7, <option>all</option> can be
used as the <replaceable>zone</replaceable> name to mean
<firstterm>all zones</firstterm>.</para>
<para>Beginning with Shorewall 4.5.10, <option>all-</option> can be
used as the <replaceable>zone</replaceable> name to mean all
<firstterm>off-firewall zone</firstterm>s.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>SOURCE (format 3)
{-|<emphasis>interface</emphasis>[:<emphasis>address-list</emphasis>]|<replaceable>address-list</replaceable>}</term>
<listitem>
<para>Where <replaceable>interface</replaceable> is an interface to
that zone, and <replaceable>address-list</replaceable> is a
comma-separated list of addresses (may contain exclusion - see
<ulink url="shorewall-exclusion.html">shorewall-exclusion</ulink>
(5)).</para>
<para>COMMENT is only allowed in format 1; the remainder of the line
is treated as a comment that will be associated with the generated
rule(s).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>DEST
{-|<emphasis>interface</emphasis>[:<emphasis>address-list</emphasis>]|<replaceable>address-list</replaceable>}</term>
<listitem>
<para>where <replaceable>address-list</replaceable> is a
comma-separated list of addresses (may contain exclusion - see
<ulink url="shorewall-exclusion.html">shorewall6-exclusion</ulink>
(5)).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>PROTO
<replaceable>protocol-name-or-number</replaceable>[,...]</term>
<listitem>
<para>A protocol name from <filename>/etc/protocols</filename> or a
protocol number.</para>
<para>Beginning with Shorewall 4.5.12, this column can accept a
comma-separated list of protocols.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>DEST PORT(S) (dport) - port-number/service-name-list</term>
<listitem>
<para>A comma-separated list of port numbers and/or service names
from <filename>/etc/services</filename>. May also include port
ranges of the form
<replaceable>low-port</replaceable>:<replaceable>high-port</replaceable>
if your kernel and iptables include port range support.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>SOURCE PORT(S) (sport) - port-number/service-name-list</term>
<listitem>
<para>A comma-separated list of port numbers and/or service names
from <filename>/etc/services</filename>. May also include port
ranges of the form
<replaceable>low-port</replaceable>:<replaceable>high-port</replaceable>
if your kernel and iptables include port range support.</para>
<para>Beginning with Shorewall 4.5.15, you may place '=' in this
column, provided that the DEST PORT(S) column is non-empty. This
causes the rule to match when either the source port or the
destination port in a packet matches one of the ports specified in
DEST PORTS(S).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>USER/GROUP (user)
[<replaceable>user</replaceable>][:<replaceable>group</replaceable>]</term>
<listitem>
<para>May only be specified if the SOURCE
<replaceable>zone</replaceable> is $FW. Specifies the effective user
id and or group id of the process sending the traffic.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SWITCH -
[!]<replaceable>switch-name</replaceable>[={0|1}]</emphasis></term>
<listitem>
<para>Added in Shorewall6 4.5.10 and allows enabling and disabling
the rule without requiring <command>shorewall6
restart</command>.</para>
<para>Enables the rule if the value stored in
<filename>/proc/net/nf_condition/<replaceable>switch-name</replaceable></filename>
is 1. Disables the rule if that file contains 0 (the default). If
'!' is supplied, the test is inverted such that the rule is enabled
if the file contains 0.</para>
<para>Within the <replaceable>switch-name</replaceable>, '@0' and
'@{0}' are replaced by the name of the chain to which the rule is a
added. The <replaceable>switch-name</replaceable> (after '@...'
expansion) must begin with a letter and be composed of letters,
decimal digits, underscores or hyphens. Switch names must be 30
characters or less in length.</para>
<para>Switches are normally <emphasis role="bold">off</emphasis>. To
turn a switch <emphasis role="bold">on</emphasis>:</para>
<simplelist>
<member><command>echo 1 &gt;
/proc/net/nf_condition/<replaceable>switch-name</replaceable></command></member>
</simplelist>
<para>To turn it <emphasis role="bold">off</emphasis> again:</para>
<simplelist>
<member><command>echo 0 &gt;
/proc/net/nf_condition/<replaceable>switch-name</replaceable></command></member>
</simplelist>
<para>Switch settings are retained over <command>shorewall6
restart</command>.</para>
<para>When the <replaceable>switch-name</replaceable> is followed by
<option>=0</option> or <option>=1</option>, then the switch is
initialized to off or on respectively by the
<command>start</command> command. Other commands do not affect the
switch setting.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>EXAMPLES</title>
<para>Example 1:</para>
<para>Use the FTP helper for TCP port 21 connections from the firewall
itself.</para>
<programlisting>FORMAT 2
#ACTION SOURCE DEST PROTO DEST SOURCE USER/GROUP
# PORT(S) PORT(S)
CT:helper:ftp(expevents=new) fw - tcp 21 </programlisting>
<para>Example 2 (Shorewall 4.5.10 or later):</para>
<para>Drop traffic to/from all zones to IP address 2001:1.2.3::4</para>
<programlisting>FORMAT 2
#ACTION SOURCE DEST PROTO DEST SOURCE USER/GROUP
# PORT(S) PORT(S)
DROP all-:2001:1.2.3::4 -
DROP all 2001:1.2.3::4
</programlisting>
<para>or<programlisting>FORMAT 3
#ACTION SOURCE DEST PROTO DEST SOURCE USER/GROUP
# PORT(S) PORT(S)
DROP:P 2001:1.2.3::4 -
DROP:PO - 2001:1.2.3::4
</programlisting></para>
</refsect1>
<refsect1>
<title>FILES</title>
<para>/etc/shorewall6/notrack</para>
</refsect1>
<refsect1>
<title>See ALSO</title>
<para><ulink
url="http://shorewall.net/configuration_file_basics.htm#Pairs">http://shorewall.net/configuration_file_basics.htm#Pairs</ulink></para>
<para>shorewall6(8), shorewall6-accounting(5), shorewall6-actions(5),
shorewall6-blacklist(5), shorewall6-hosts(5), shorewall6-interfaces(5),
shorewall6-ipsec(5), shorewall6-netmap(5),shorewall6-params(5),
shorewall6-policy(5), shorewall6-providers(5), shorewall6-proxyarp(5),
shorewall6-rtrules(5), shorewall6-routestopped(5), shorewall6-rules(5),
shorewall6.conf(5), shorewall6-secmarks(5), shorewall6-tcclasses(5),
shorewall6-tcdevices(5), shorewall6-mangle(5), shorewall6-tos(5),
shorewall6-tunnels(5), shorewall-zones(5)</para>
</refsect1>
</refentry>