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shorewall_code/Shorewall/manpages/shorewall-rules.xml
Tom Eastep edc9e25f25
Deprecate 'all[+]-' 
Signed-off-by: Tom Eastep <teastep@shorewall.net>
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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>shorewall-rules</refentrytitle>
<manvolnum>5</manvolnum>
<refmiscinfo>Configuration Files</refmiscinfo>
</refmeta>
<refnamediv>
<refname>rules</refname>
<refpurpose>Shorewall rules file</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>/etc/shorewall[6]/rules</command>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>Entries in this file govern connection establishment by defining
exceptions to the policies laid out in <ulink
url="/manpages/shorewall-policy.html">shorewall-policy</ulink>(5). By
default, subsequent requests and responses are automatically allowed using
connection tracking. For any particular (source,dest) pair of zones, the
rules are evaluated in the order in which they appear in this file and the
first terminating match is the one that determines the disposition of the
request. All rules are terminating except LOG and COUNT rules.</para>
<warning>
<para>If you masquerade or use SNAT from a local system to the internet,
you cannot use an ACCEPT rule to allow traffic from the internet to that
system. You <emphasis role="bold">must</emphasis> use a DNAT rule
instead.</para>
</warning>
<para>The rules file is divided into sections. Each section is introduced
by a "Section Header" which is a line beginning with ?SECTION and followed
by the section name.</para>
<para>Sections are as follows and must appear in the order listed:</para>
<variablelist>
<varlistentry>
<term><emphasis role="bold">ALL</emphasis></term>
<listitem>
<para>This section was added in Shorewall 4.4.23. Rules in this
section are applied, regardless of the connection tracking state of
the packet and are applied before rules in the other
sections.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">ESTABLISHED</emphasis></term>
<listitem>
<para>Packets in the ESTABLISHED state are processed by rules in
this section.</para>
<para>The only ACTIONs allowed in this section are ACCEPT, DROP,
REJECT, LOG, NFLOG, NFQUEUE and QUEUE</para>
<para>There is an implicit ACCEPT rule inserted at the end of this
section.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">RELATED</emphasis></term>
<listitem>
<para>Packets in the RELATED state are processed by rules in this
section.</para>
<para>The only ACTIONs allowed in this section are ACCEPT, DROP,
REJECT, LOG, NFLOG, NFQUEUE and QUEUE</para>
<para>There is an implicit rule added at the end of this section
that invokes the RELATED_DISPOSITION (<ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5)).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">INVALID</emphasis></term>
<listitem>
<para>Added in Shorewall 4.5.13. Packets in the INVALID state are
processed by rules in this section.</para>
<para>The only Actions allowed in this section are ACCEPT, DROP,
REJECT, LOG, NFLOG, NFQUEUE and QUEUE.</para>
<para>There is an implicit rule added at the end of this section
that invokes the INVALID_DISPOSITION (<ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5)).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">UNTRACKED</emphasis></term>
<listitem>
<para>Added in Shorewall 4.5.13. Packets in the UNTRACKED state are
processed by rules in this section.</para>
<para>The only Actions allowed in this section are ACCEPT, DROP,
REJECT, LOG, NFLOG, NFQUEUE and QUEUE.</para>
<para>There is an implicit rule added at the end of this section
that invokes the UNTRACKED_DISPOSITION (<ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5)).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">NEW</emphasis></term>
<listitem>
<para>Packets in the NEW state are processed by rules in this
section. If the INVALID and/or UNTRACKED sections are empty or not
included, then the packets in the corresponding state(s) are also
processed in this section.</para>
</listitem>
</varlistentry>
</variablelist>
<note>
<para>If you are not familiar with Netfilter to the point where you are
comfortable with the differences between the various connection tracking
states, then it is suggested that you place all of your rules in the NEW
section (That's after the line that reads ?SECTION NEW').</para>
</note>
<warning>
<para>If you specify FASTACCEPT=Yes in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5) then the
<emphasis role="bold">ALL, ESTABLISHED</emphasis> and <emphasis
role="bold">RELATED</emphasis> sections must be empty.</para>
<para>An exception is made if you are running Shorewall 4.4.27 or later
and you have specified a non-default value for RELATED_DISPOSITION or
RELATED_LOG_LEVEL. In that case, you may have rules in the RELATED
section of this file.</para>
</warning>
<para>You may omit any section that you don't need. If no Section Headers
appear in the file then all rules are assumed to be in the NEW
section.</para>
<para>When defining rules that rewrite the destination IP address and/or
port number (namely DNAT and REDIRECT rules), it is important to keep
straight which columns in the file specify the packet before rewriting and
which specify how the packet will look after rewriting.</para>
<itemizedlist>
<listitem>
<para>The DEST column specifies the final destination for the packet
after rewriting and can include the final IP address and/or port
number.</para>
</listitem>
<listitem>
<para>The remaining columns specify characteristics of the packet
before rewriting. In particular, the ORIGDEST column gives the
original destination IP address of the packet and the DPORT column
give the original destination port(s).</para>
</listitem>
</itemizedlist>
<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"><replaceable>target</replaceable>[:</emphasis>{<emphasis>log-level</emphasis>|<emphasis
role="bold">none</emphasis>}[<emphasis role="bold"><emphasis
role="bold">!</emphasis></emphasis>][<emphasis
role="bold">:</emphasis><emphasis>tag</emphasis>]]</term>
<listitem>
<para>Specifies the action to be taken if the connection request
matches the rule. <replaceable>target</replaceable> must be one of
the following.</para>
<variablelist>
<varlistentry>
<term><emphasis role="bold">ACCEPT</emphasis></term>
<listitem>
<para>Allow the connection request.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">ACCEPT+</emphasis></term>
<listitem>
<para>like ACCEPT but also excludes the connection from any
subsequent matching <emphasis
role="bold">DNAT</emphasis>[<emphasis
role="bold">-</emphasis>] or <emphasis
role="bold">REDIRECT</emphasis>[<emphasis
role="bold">-</emphasis>] rules. Use with IPv6 requires
Shorewall 4.5.14 or later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">ACCEPT!</emphasis></term>
<listitem>
<para>like ACCEPT but exempts the rule from being suppressed
by OPTIMIZE=1 in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis>action</emphasis></term>
<listitem>
<para>The name of an <emphasis>action</emphasis> declared in
<ulink
url="/manpages/shorewall-actions.html">shorewall-actions</ulink>(5)
or in /usr/share/shorewall[6]/actions.std.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">ADD(<replaceable>ipset</replaceable>:<replaceable>flags</replaceable>[:<replaceable>timeout</replaceable>])</emphasis></term>
<listitem>
<para>Added in Shorewall 4.4.12. Causes addresses and/or port
numbers to be added to the named
<replaceable>ipset</replaceable>. The
<replaceable>flags</replaceable> specify the address or tuple
to be added to the set and must match the type of ipset
involved. For example, for an iphash ipset, either the SOURCE
or DESTINATION address can be added using
<replaceable>flags</replaceable> <emphasis
role="bold">src</emphasis> or <emphasis
role="bold">dst</emphasis> respectively (see the -A command in
ipset (8)).</para>
<para>Beginning with Shorewall 5.0.3, an optional
<replaceable>timeout</replaceable> can be specified. This is
the number of seconds that the new entry in the ipset is to
remain valid and overrides any timeout specified when the
ipset was created.</para>
<para>ADD is non-terminating. Even if a packet matches the
rule, it is passed on to the next rule.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">AUDIT</emphasis>[(accept|drop|reject)]</term>
<listitem>
<para>Added in Shorewall 4.5.10. Audits the packet with the
specified type; if the type is omitted, then
<option>drop</option> is assumed. Require AUDIT_TARGET support
in the kernel and iptables.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">A_ACCEPT</emphasis>, <emphasis
role="bold">A_ACCEPT</emphasis><emphasis
role="bold">+</emphasis> and <emphasis
role="bold">A_ACCEPT</emphasis><emphasis
role="bold">!</emphasis></term>
<listitem>
<para>Added in Shorewall 4.4.20. Audited versions of ACCEPT,
ACCEPT+ and ACCEPT! respectively. Require AUDIT_TARGET support
in the kernel and iptables. A_ACCEPT+ with IPv6 requires
Shorewall 4.5.14 or later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">A_DROP</emphasis> and<emphasis
role="bold"> A_DROP!</emphasis></term>
<listitem>
<para>Added in Shorewall 4.4.20. Audited versions of DROP and
DROP! respectively. Require AUDIT_TARGET support in the kernel
and iptables.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">A_REJECT</emphasis> AND <emphasis
role="bold">A_REJECT!</emphasis></term>
<listitem>
<para>Added in Shorewall 4.4.20. Audited versions of REJECT
and REJECT! respectively. Require AUDIT_TARGET support in the
kernel and iptables.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">?COMMENT</emphasis></term>
<listitem>
<para>the rest of the line will be attached as a comment to
the Netfilter rule(s) generated by the following entries. The
comment will appear delimited by "/* ... */" in the output of
"shorewall show &lt;chain&gt;". To stop the comment from being
attached to further rules, simply include ?COMMENT on a line
by itself.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">CONMARK({<replaceable>mark</replaceable>})</emphasis></term>
<listitem>
<para>Added in Shorewall 5.0.7, CONNMARK is identical to MARK
with the exception that the mark is assigned to connection to
which the packet belongs is marked rather than to the packet
itself.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">CONTINUE</emphasis></term>
<listitem>
<para>For experts only.</para>
<para>Do not process any of the following rules for this
(source zone,destination zone). If the source and/or
destination IP address falls into a zone defined later in
<ulink
url="/manpages/shorewall-zones.html">shorewall-zones</ulink>(5)
or in a parent zone of the source or destination zones, then
this connection request will be passed to the rules defined
for that (those) zone(s). See <ulink
url="/manpages/shorewall-nesting.html">shorewall-nesting</ulink>(5)
for additional information.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">CONTINUE!</emphasis></term>
<listitem>
<para>like CONTINUE but exempts the rule from being suppressed
by OPTIMIZE=1 in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">COUNT</emphasis></term>
<listitem>
<para>Simply increment the rule's packet and byte count and
pass the packet to the next rule.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">DEL(<replaceable>ipset</replaceable>:<replaceable>flags</replaceable>)</emphasis></term>
<listitem>
<para>Added in Shorewall 4.4.12. Causes an entry to be deleted
from the named <replaceable>ipset</replaceable>. The
<replaceable>flags</replaceable> specify the address or tuple
to be deleted from the set and must match the type of ipset
involved. For example, for an iphash ipset, either the SOURCE
or DESTINATION address can be deleted using
<replaceable>flags</replaceable> <emphasis
role="bold">src</emphasis> or <emphasis
role="bold">dst</emphasis> respectively (see the -D command in
ipset (8)).</para>
<para>DEL is non-terminating. Even if a packet matches the
rule, it is passed on to the next rule.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DNAT</emphasis></term>
<listitem>
<para>Forward the request to another system (and optionally
another port). Use with IPv6 requires Shorewall 4.5.14 or
later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DNAT-</emphasis></term>
<listitem>
<para>Advanced users only.</para>
<para>Like <emphasis role="bold">DNAT</emphasis> but only
generates the <emphasis role="bold">DNAT</emphasis> iptables
rule and not the companion <emphasis
role="bold">ACCEPT</emphasis> rule. Use with IPv6 requires
Shorewall 4.5.14 or later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DROP</emphasis></term>
<listitem>
<para>Ignore the request.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DROP!</emphasis></term>
<listitem>
<para>like DROP but exempts the rule from being suppressed by
OPTIMIZE=1 in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">HELPER</emphasis></term>
<listitem>
<para>Added in Shorewall 4.5.7. This action requires that the
HELPER column contains the name of the Netfilter helper to be
associated with connections matching this connection. May only
be specified in the NEW section and is useful for being able
to specify a helper when the applicable policy is ACCEPT. No
destination zone should be specified in HELPER rules.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">INLINE</emphasis>[(<replaceable>action</replaceable>)]</term>
<listitem>
<para>Added in Shorewall 4.5.16. This action allows you to
construct most of the rule yourself using iptables syntax. The
part that you specify must follow two semicolons (';;') and is
completely free-form. If the target of the rule (the part
following 'j') is something that Shorewall supports in the
ACTION column, then you may enclose it in parentheses (e.g.,
INLINE(ACCEPT)). Otherwise, you can include it after the
semicolon(s). In this case, you must declare the target as a
builtin action in <ulink
url="/manpages/shorewall-actions.html">shorewall-actions</ulink>(5).</para>
<para>Some considerations when using INLINE:</para>
<itemizedlist>
<listitem>
<para>The <option>p</option>, <option>s</option>,
<option>d</option>, <option>i</option>,
<option>o</option>, <option>policy</option>, and state
match (<option>state</option> or <option>conntrack
--ctstate</option>) matches will always appear in the
front of the rule in that order.</para>
</listitem>
<listitem>
<para>When multiple matches are specified, the compiler
will keep them in the order in which they appear
(excluding the above listed ones), but they will not
necessarily be at the end of the generated rule. For
example, if addresses are specified in the SOURCE and/or
DEST columns, their generated matches will appear after
those specified using ';;' or ';'.</para>
</listitem>
</itemizedlist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">IPTABLES</emphasis>({<replaceable>iptables-target</replaceable>
[<replaceable>option</replaceable> ...])</term>
<listitem>
<para>IPv4 only. This action allows you to specify an iptables
target with options (e.g., 'IPTABLES(MARK --set-xmark
0x01/0xff)'. If the <replaceable>iptables-target</replaceable>
is not one recognized by Shorewall, the following error
message will be issued:</para>
<programlisting> ERROR: Unknown target (<replaceable>iptables-target</replaceable>)</programlisting>
<para>This error message may be eliminated by adding the
<replaceable>iptables-</replaceable><replaceable>target</replaceable>
as a builtin action in <ulink
url="/manpages/shorewall-actions.html">shorewall-actions</ulink>(5).</para>
<important>
<para>If you specify REJECT as the
<replaceable>iptables-target</replaceable>, the target of
the rule will be the iptables REJECT target and not
Shorewall's builtin 'reject' chain which is used when REJECT
(see below) is specified as the
<replaceable>target</replaceable> in the ACTION
column.</para>
</important>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">IP6TABLES</emphasis>({<replaceable>ip6tables-target</replaceable>
[<replaceable>option</replaceable> ...])</term>
<listitem>
<para>IPv6 only. This action allows you to specify an
ip6tables target with options (e.g., 'IPTABLES(MARK
--set-xmark 0x01/0xff)'. If the
<replaceable>ip6tables-target</replaceable> is not one
recognized by Shorewall, the following error message will be
issued:</para>
<programlisting> ERROR: Unknown target (<replaceable>ip6tables-target</replaceable>)</programlisting>
<para>This error message may be eliminated by adding
the<replaceable>
ip6tables-</replaceable><replaceable>target</replaceable> as a
builtin action in <ulink
url="/manpages6/shorewall6-actions.html">shorewall-actions</ulink>(5).</para>
<important>
<para>If you specify REJECT as the
<replaceable>ip6tables-target</replaceable>, the target of
the rule will be the i6ptables REJECT target and not
Shorewall's builtin 'reject' chain which is used when REJECT
(see below) is specified as the
<replaceable>target</replaceable> in the ACTION
column.</para>
</important>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">LOG:<replaceable>level</replaceable></emphasis></term>
<listitem>
<para>Simply log the packet and continue with the next
rule.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis>macro</emphasis><emphasis
role="bold">[(<replaceable>macrotarget</replaceable>)]</emphasis></term>
<listitem>
<para>The name of a macro defined in a file named
macro.<emphasis>macro</emphasis>. If the macro accepts an
action parameter (Look at the macro source to see if it has
PARAM in the TARGET column) then the
<emphasis>macro</emphasis> name is followed by the
parenthesized <emphasis>macrotarget</emphasis> (<emphasis
role="bold">ACCEPT</emphasis>, <emphasis
role="bold">DROP</emphasis>, <emphasis
role="bold">REJECT</emphasis>, ...) to be substituted for the
parameter.</para>
<para>Example: FTP(ACCEPT).</para>
<para>The older syntax where the macro name and the target are
separated by a slash (e.g. FTP/ACCEPT) is still allowed but is
deprecated.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">MARK({<replaceable>mark</replaceable>})</emphasis></term>
<listitem>
<para>where <replaceable>mark</replaceable> is a packet mark
value.</para>
<para>Added in Shorewall 5.0.7, MARK requires "Mark in filter
table" support in your kernel and iptables.</para>
<para>Normally will set the mark value of the current packet.
If preceded by a vertical bar ("|"), the mark value will be
logically ORed with the current mark value to produce a new
mark value. If preceded by an ampersand ("&amp;"), will be
logically ANDed with the current mark value to produce a new
mark value.</para>
<para>Both "|" and "&amp;" require Extended MARK Target
support in your kernel and iptables.</para>
<para>The mark value may be optionally followed by "/" and a
mask value (used to determine those bits of the connection
mark to actually be set). When a mask is specified, the result
of logically ANDing the mark value with the mask must be the
same as the mark value.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">NFLOG</emphasis>[(<replaceable>nflog-parameters</replaceable>)]</term>
<listitem>
<para>Added in Shorewall 4.5.9.3. Queues matching packets to a
back end logging daemon via a netlink socket then continues to
the next rule. See <ulink
url="/shorewall_logging.html">http://www.shorewall.net/shorewall_logging.html</ulink>.</para>
<para>The <replaceable>nflog-parameters</replaceable> are a
comma-separated list of up to 3 numbers:</para>
<itemizedlist>
<listitem>
<para>The first number specifies the netlink group
(0-65535). If omitted (e.g., NFLOG(,0,10)) then a value of
0 is assumed.</para>
</listitem>
<listitem>
<para>The second number specifies the maximum number of
bytes to copy. If omitted, 0 (no limit) is assumed.</para>
</listitem>
<listitem>
<para>The third number specifies the number of log
messages that should be buffered in the kernel before they
are sent to user space. The default is 1.</para>
</listitem>
</itemizedlist>
<para>NFLOG is similar to<emphasis role="bold">
LOG:NFLOG</emphasis>[(<replaceable>nflog-parameters</replaceable>)],
except that the log level is not changed when this ACTION is
used in an action or macro body and the invocation of that
action or macro specifies a log level.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">NFQUEUE</emphasis>[([<replaceable>queuenumber</replaceable>1[:<replaceable>queuenumber2</replaceable>[c]][,bypass]]|bypass)]</term>
<listitem>
<para>Queues the packet to a user-space application using the
nfnetlink_queue mechanism. If a
<replaceable>queuenumber</replaceable>1 is not specified,
queue zero (0) is assumed. Beginning with Shorewall 4.6.10,
the keyword <emphasis role="bold">bypass</emphasis> can be
given. By default, if no userspace program is listening on an
NFQUEUE, then all packets that are to be queued are dropped.
When this option is used, the NFQUEUE rule is silently
bypassed instead. The packet will move on to the next rule.
Also beginning in Shorewall 4.6.10, a second queue number
(<replaceable>queuenumber2</replaceable>) may be specified.
This specifies a range of queues to use. Packets are then
balanced across the given queues. This is useful for multicore
systems: start multiple instances of the userspace program on
queues x, x+1, .. x+n and use "x:x+n". Packets belonging to
the same connection are put into the same nfqueue.</para>
<para>Beginning with Shorewall 5.1.0, queuenumber2 may be
followed by the letter 'c' to indicate that the CPU ID will be
used as an index to map packets to the queues. The idea is
that you can improve performance if there's a queue per CPU.
Requires the NFQUEUE CPU Fanout capability in your kernel and
iptables.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold"><emphasis
role="bold">NFQUEUE!</emphasis>[([<replaceable>queuenumber1</replaceable>[:<replaceable>queuenumber2</replaceable>[c]][,bypass]]|bypass)]</emphasis></term>
<listitem>
<para>like NFQUEUE but exempts the rule from being suppressed
by OPTIMIZE=1 in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">NONAT</emphasis></term>
<listitem>
<para>Excludes the connection from any subsequent <emphasis
role="bold">DNAT</emphasis>[-] or <emphasis
role="bold">REDIRECT</emphasis>[-] rules but doesn't generate
a rule to accept the traffic. Use with IPv6 requires Shorewall
4.5.14 or later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">QUEUE</emphasis></term>
<listitem>
<para>Queue the packet to a user-space application such as
ftwall (http://p2pwall.sf.net). The application may reinsert
the packet for further processing.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">QUEUE!</emphasis></term>
<listitem>
<para>like QUEUE but exempts the rule from being suppressed by
OPTIMIZE=1 in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">REJECT[(<replaceable>option</replaceable>)]</emphasis></term>
<listitem>
<para>disallow the request and return an icmp-unreachable or
an RST packet. If no option is passed, Shorewall selects the
appropriate option based on the protocol of the packet.</para>
<para>Beginning with Shorewall 5.0.8, the type of reject may
be specified in the <replaceable>option</replaceable>
paramater. Valid IPv4 <replaceable>option</replaceable> values
are:</para>
<simplelist>
<member><option>icmp-net-unreachable</option></member>
<member><option>icmp-host-unreachable</option></member>
<member><option>i</option><option>cmp-port-unreachable</option></member>
<member><option>icmp-proto-unreachable</option></member>
<member><option>icmp-net-prohibited</option></member>
<member><option>icmp-host-prohibited</option></member>
<member><option>icmp-admin-prohibited</option></member>
<member><option>icmp-tcp-reset</option> (the PROTO column
must specify TCP). Beginning with Shorewall 5.1.3, this
option may also be specified as
<option>tcp-reset</option>.</member>
</simplelist>
<para>Valid IPv6 <replaceable>option</replaceable> values
are:</para>
<simplelist>
<member><option>icmp6-no-route</option></member>
<member><option>no-route</option></member>
<member><option>i</option><option>cmp6-adm-prohibited</option></member>
<member><option>adm-prohibited</option></member>
<member><option>icmp6-addr-unreachable</option></member>
<member><option>addr-unreach</option></member>
<member><option>icmp6-port-unreachable</option></member>
<member><option>tcp-reset</option> (the PROTO column must
specify TCP)</member>
</simplelist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">REJECT!</emphasis></term>
<listitem>
<para>like REJECT but exempts the rule from being suppressed
by OPTIMIZE=1 in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">REDIRECT</emphasis></term>
<listitem>
<para>Redirect the request to a server running on the
firewall. Use with IPv6 requires Shorewall 4.5.14 or
later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">REDIRECT-</emphasis></term>
<listitem>
<para>Advanced users only.</para>
<para>Like <emphasis role="bold">REDIRECT</emphasis> but only
generates the <emphasis role="bold">REDIRECT</emphasis>
iptables rule and not the companion <emphasis
role="bold">ACCEPT</emphasis> rule. Use with IPv6 requires
Shorewall 4.5.14 or later.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">TARPIT</emphasis> [(<emphasis
role="bold">tarpit</emphasis> | <emphasis
role="bold">honeypot</emphasis> | <emphasis
role="bold">reset</emphasis>)]</term>
<listitem>
<para>Added in Shorewall 4.6.6.</para>
<para>TARPIT captures and holds incoming TCP connections using
no local per-connection resources.</para>
<para>TARPIT only works with the PROTO column set to tcp (6),
and is totally application agnostic. This module will answer a
TCP request and play along like a listening server, but aside
from sending an ACK or RST, no data is sent. Incoming packets
are ignored and dropped. The attacker will terminate the
session eventually. This module allows the initial packets of
an attack to be captured by other software for inspection. In
most cases this is sufficient to determine the nature of the
attack.</para>
<para>This offers similar functionality to LaBrea
&lt;http://www.hackbusters.net/LaBrea/&gt; but does not
require dedicated hardware or IPs. Any TCP port that you would
normally DROP or REJECT can instead become a tarpit.</para>
<para>The target accepts a single optional parameter:</para>
<variablelist>
<varlistentry>
<term>tarpit</term>
<listitem>
<para>This mode is the default and completes a
connection with the attacker but limits the window size
to 0, thus keeping the attacker waiting long periods of
time. While he is maintaining state of the connection
and trying to continue every 60-240 seconds, we keep
none, so it is very lightweight. Attempts to close the
connection are ignored, forcing the remote side to time
out the connection in 12-24 minutes.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>honeypot</term>
<listitem>
<para>This mode completes a connection with the
attacker, but signals a normal window size, so that the
remote side will attempt to send data, often with some
very nasty exploit attempts. We can capture these
packets for decoding and further analysis. The module
does not send any data, so if the remote expects an
application level response, the game is up.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>reset</term>
<listitem>
<para>This mode is handy because we can send an inline
RST (reset). It has no other function.</para>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis
role="bold">ULOG</emphasis>[(<replaceable>ulog-parameters</replaceable>)]</term>
<listitem>
<para>IPv4 only. Added in Shorewall 4.5.10. Queues matching
packets to a back end logging daemon via a netlink socket then
continues to the next rule. See <ulink
url="shorewall-logging.html">shorewall-logging(5)</ulink>.</para>
<para>Similar to<emphasis role="bold">
LOG:ULOG</emphasis>[(<replaceable>ulog-parameters</replaceable>)],
except that the log level is not changed when this ACTION is
used in an action or macro body and the invocation of that
action or macro specifies a log level.</para>
</listitem>
</varlistentry>
</variablelist>
<para>The <replaceable>target</replaceable> may optionally be
followed by ":" and a syslog log level (e.g, REJECT:info or
Web(ACCEPT):debug). This causes the packet to be logged at the
specified level. Note that if the <emphasis
role="bold">ACTION</emphasis> involves destination network address
translation (DNAT, REDIRECT, etc.) then the packet is logged
<emphasis role="bold">before</emphasis> the destination address is
rewritten.</para>
<para>If the <emphasis role="bold">ACTION</emphasis> names an
<emphasis>action</emphasis> declared in <ulink
url="/manpages/shorewall-actions.html">shorewall-actions</ulink>(5)
or in /usr/share/shorewall/actions.std then:</para>
<itemizedlist>
<listitem>
<para>If the log level is followed by "!' then all rules in the
action are logged at the log level.</para>
</listitem>
<listitem>
<para>If the log level is not followed by "!" then only those
rules in the action that do not specify logging are logged at
the specified level.</para>
</listitem>
<listitem>
<para>The special log level <emphasis
role="bold">none!</emphasis> suppresses logging by the
action.</para>
</listitem>
</itemizedlist>
<para>You may also specify <emphasis role="bold">ULOG</emphasis>
(IPv4 only) or <emphasis role="bold">NFLOG</emphasis> (must be in
upper case) as a log level.This will log to the ULOG or NFLOG target
for routing to a separate log through use of ulogd (<ulink
url="shorewall-logging.html">shorewall-logging(5)</ulink>).</para>
<para>Actions specifying logging may be followed by a log tag (a
string of alphanumeric characters) which is appended to the string
generated by the LOGPREFIX (in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5)).</para>
<para>Example: ACCEPT:info:ftp would include 'ftp ' at the end of
the log prefix generated by the LOGPREFIX setting.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SOURCE -
<replaceable>source-spec</replaceable>[,...]</emphasis></term>
<listitem>
<para>Source hosts to which the rule applies.</para>
<para><replaceable>source-spec</replaceable> is one of the
following:</para>
<variablelist>
<varlistentry>
<term><emphasis
role="bold"><replaceable>zone</replaceable>[,...[+]]</emphasis></term>
<listitem>
<para>The name of a zone defined in <ulink
url="/manpages/shorewall-zones.html">shorewall-zones</ulink>(5).
When only the zone name is specified, the packet source may be
any host in that zone.</para>
<para>zone may also be one of the following:</para>
<variablelist>
<varlistentry>
<term>all[+]</term>
<listitem>
<para><emphasis role="bold">all</emphasis>, without the
"-" means "All Zones, including the firewall zone".
Normally all omits intra-zone traffic, but intra-zone
traffic can be included specifying "+".</para>
</listitem>
</varlistentry>
<varlistentry>
<term>any[+]</term>
<listitem>
<para><emphasis role="bold">any</emphasis> is equivalent
to <emphasis role="bold">all</emphasis> when there are
no nested zones. When there are nested zones, <emphasis
role="bold">any</emphasis> only refers to top-level
zones (those with no parent zones). Note that <emphasis
role="bold">any</emphasis> excludes all vserver zones,
since those zones are nested within the firewall
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>none</term>
<listitem>
<para>When <emphasis role="bold">none</emphasis> is used
either in the <emphasis role="bold">SOURCE</emphasis> or
<emphasis role="bold">DEST</emphasis> column, the rule
is ignored.</para>
</listitem>
</varlistentry>
</variablelist>
<para>Similar to with <emphasis role="bold">all</emphasis> and
<emphasis role="bold">any</emphasis>, intra-zone traffic is
normally excluded when multiple zones are listed. Intra-zone
traffic may be included by following the list with a plus sign
("+").</para>
<para><emphasis role="bold">all</emphasis> and <emphasis
role="bold">any</emphasis> may be followed by an exclamation
point ("!") and a comma-separated list of zone names to be
omitted.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:[!]<replaceable>interface</replaceable></term>
<listitem>
<para>When this form is used,
<replaceable>interface</replaceable> must be the name of an
interface associated with the named
<replaceable>zone</replaceable> in either <ulink
url="/manpages/shorewall-interfaces.html">shorewall-interfaces</ulink>(5)
or <ulink
url="/manpages/shorewall.hosts.html">shorewall-hosts</ulink>(5).
Only packets from hosts in the <replaceable>zone</replaceable>
that arrive through the named interface will match the
rule.</para>
<para>Beginning with Shorweall 5.2.1, the
<replaceable>interface</replaceable> may be preceded with '!'
which matches all interfaces associated with the zone except
the one specified.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:<replaceable>address</replaceable>[,...]</term>
<listitem>
<para>where address can be:</para>
<itemizedlist>
<listitem>
<para>A host or network IP address. A network address may
be followed by exclusion (see <ulink
url="/manpages/shorewall-exclusion.html">shorewall-exclusion</ulink>(5)).</para>
</listitem>
<listitem>
<para>An address range, specified using the syntax
<emphasis>lowaddress</emphasis>-<emphasis>highaddress</emphasis>.</para>
</listitem>
<listitem>
<para>+<replaceable>ipset</replaceable> where
<replaceable>ipset</replaceable> is the name of an ipset
and must be preceded by a plus sign ("+").</para>
</listitem>
<listitem>
<para>A MAC address in Shorewall format (preceded by a
tilde ("~") and with the hex byte values separated by
dashes (e.g., "~00-0a-f6-04-9c-7d").</para>
</listitem>
<listitem>
<para>^<replaceable>country-code</replaceable> where
country-code is a two-character ISO-3661 country code
preceded by a caret ("^").</para>
</listitem>
<listitem>
<para>^<replaceable>country-code-list</replaceable> where
<replaceable>country-code-list</replaceable> is a
comma-separated list of up to 15 ISO-3661 country codes
enclosed in square brackets ("[...]").</para>
</listitem>
<listitem>
<para>The primary IP address of a firewall interface can
be specified by an ampersand ('&amp;') followed by the
logical name of the interface as found in the INTERFACE
column of <ulink
url="/manpages/shorewall-interfaces.html">shorewall-interfaces</ulink>
(5).</para>
</listitem>
</itemizedlist>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:<replaceable>interface</replaceable>:<replaceable>address</replaceable>[,...]</term>
<listitem>
<para>This form combines the preceding two and requires that
both the incoming interface and source address match.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:<replaceable>exclusion</replaceable></term>
<listitem>
<para>This form matches if the host IP address does not match
any of the entries in the exclusion (see <ulink
url="/manpages/shorewall-exclusion.html">shorewall-exclusion</ulink>(5)).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:<replaceable>interface</replaceable>:<replaceable>exclusion</replaceable></term>
<listitem>
<para>This form matches packets from the named
<replaceable>zone</replaceable> entering through the specified
<replaceable>interface</replaceable> where the source address
does not match any entry in the
<replaceable>exclusion</replaceable>.</para>
</listitem>
</varlistentry>
</variablelist>
<para>Beginning with Shorewall 5.1.0, multiple
<replaceable>source-spec</replaceable>s may be listed, provided that
extended forms of the source-spec are used:</para>
<blockquote>
<para><replaceable>zone</replaceable>:(<replaceable>interface</replaceable>)</para>
<para><replaceable>zone</replaceable>:(<replaceable>address</replaceable>[,...])</para>
<para>zone:(interface:address[,...])</para>
<para><replaceable>zone</replaceable>:(<replaceable>exclusion</replaceable>)</para>
<para><replaceable>zone</replaceable>:(<replaceable>interface</replaceable>:<replaceable>exclusion</replaceable>)</para>
</blockquote>
<para>Examples:</para>
<variablelist>
<varlistentry>
<term>dmz:192.168.2.2</term>
<listitem>
<para>Host 192.168.2.2 in the DMZ</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:155.186.235.0/24</term>
<listitem>
<para>Subnet 155.186.235.0/24 on the Internet</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:192.168.1.1,192.168.1.2</term>
<listitem>
<para>Hosts 192.168.1.1 and 192.168.1.2 in the local
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:~00-A0-C9-15-39-78</term>
<listitem>
<para>Host in the local zone with MAC address
00:A0:C9:15:39:78.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:192.0.2.11-192.0.2.17</term>
<listitem>
<para>Hosts 192.0.2.11-192.0.2.17 in the net zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:!192.0.2.11-192.0.2.17</term>
<listitem>
<para>All hosts in the net zone except for
192.0.2.11-192.0.2.17.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:155.186.235.0/24!155.186.235.16/28</term>
<listitem>
<para>Subnet 155.186.235.0/24 on the Internet except for
155.186.235.16/28</para>
</listitem>
</varlistentry>
<varlistentry>
<term>$FW:&amp;eth0</term>
<listitem>
<para>The primary IP address of eth0 in the firewall
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc,dmz</term>
<listitem>
<para>Both the <emphasis role="bold">loc</emphasis> and
<emphasis role="bold">dmz</emphasis> zones.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>all!dmz</term>
<listitem>
<para>All but the <emphasis role="bold">dmz</emphasis>
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>all+!$FW</term>
<listitem>
<para>All but the firewall zone and applies to intrazone
traffic.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:^CN</term>
<listitem>
<para>China.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:(eth1:1.2.3.4,2.3.4.5),dmz:(eth2:5.6.7.8,9.10.11.12),net</term>
<listitem>
<para>Hosts 1.2.3.4 and 2.3.4.5 in the loc zone when the
packet arrives through eth1 plus hosts 5.6.7.8 and 9.10.11.12
in the dmz zone when the packet arrives through eth2 plus all
of the net zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>dmz:[2002:ce7c:2b4:1::2]</term>
<listitem>
<para>Host 2002:ce7c:92b4:1::2 in the DMZ</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:2001:4d48:ad51:24::/64</term>
<listitem>
<para>Subnet 2001:4d48:ad51:24::/64 on the Internet</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:[2002:cec792b4:1::2],[2002:cec792b4:1::44]</term>
<listitem>
<para>Hosts 2002:cec792b4:1::2 and 2002:cec792b4:1::44 in the
local zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:~00-A0-C9-15-39-78</term>
<listitem>
<para>Host in the local zone with MAC address
00:A0:C9:15:39:78.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:[2001:4d48:ad51:24::]/64![2001:4d48:ad51:24:6::]/80</term>
<listitem>
<para>Subnet 2001:4d48:ad51:24::/64 on the Internet except for
2001:4d48:ad51:24:6::/80.</para>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DEST -
<replaceable>dest-spec</replaceable>[,...]</emphasis></term>
<listitem>
<para>Destination hosts to which the rule applies.</para>
<para><replaceable>dest-spec</replaceable> is one of the
following:</para>
<variablelist>
<varlistentry>
<term><emphasis
role="bold"><replaceable>zone</replaceable>[,...[+]]</emphasis></term>
<listitem>
<para>The name of a zone defined in <ulink
url="/manpages/shorewall-zones.html">shorewall-zones</ulink>(5).
When only the zone name is specified, the packet destination
may be any host in that zone.</para>
<para>zone may also be one of the following:</para>
<variablelist>
<varlistentry>
<term>all[+]</term>
<listitem>
<para><emphasis role="bold">all</emphasis>, without the
"-" means "All Zones, including the firewall zone".
Normally all omits intra-zone traffic, but intra-zone
traffic can be included specifying "+".</para>
</listitem>
</varlistentry>
<varlistentry>
<term>any[+]</term>
<listitem>
<para><emphasis role="bold">any</emphasis> is equivalent
to <emphasis role="bold">all</emphasis> when there are
no nested zones. When there are nested zones, <emphasis
role="bold">any</emphasis> only refers to top-level
zones (those with no parent zones). Note that <emphasis
role="bold">any</emphasis> excludes all vserver zones,
since those zones are nested within the firewall
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>none</term>
<listitem>
<para>When <emphasis role="bold">none</emphasis> is used
either in the <emphasis role="bold">SOURCE</emphasis> or
<emphasis role="bold">DEST</emphasis> column, the rule
is ignored.</para>
</listitem>
</varlistentry>
</variablelist>
<para>Similar to with <emphasis role="bold">all</emphasis> and
<emphasis role="bold">any</emphasis>, intra-zone traffic is
normally excluded when multiple zones are listed. Intra-zone
traffic may be included by following the list with a plus sign
("+").</para>
<para><emphasis role="bold">all</emphasis> and <emphasis
role="bold">any</emphasis> may be followed by an exclamation
point ("!") and a comma-separated list of zone names to be
omitted.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:[!]<replaceable>interface</replaceable></term>
<listitem>
<para>When this form is used,
<replaceable>interface</replaceable> must be the name of an
interface associated with the named
<replaceable>zone</replaceable> in either <ulink
url="/manpages/shorewall-interfaces.html">shorewall-interfaces</ulink>(5)
or <ulink
url="/manpages/shorewall-hosts.html">shorewall-hosts</ulink>(5).
Only packets to hosts in the <replaceable>zone</replaceable>
that are sent through the named interface will match the
rule.</para>
<para>Beginning with Shorweall 5.2.1, the
<replaceable>interface</replaceable> may be preceded with '!'
which matches all interfaces associated with the zone except
the one specified.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:<replaceable>address</replaceable>[,...]</term>
<listitem>
<para>where address can be:</para>
<itemizedlist>
<listitem>
<para>A host or network IP address. A network address may
be followed by exclusion (see <ulink
url="/manpages/shorewall-exclusion.html">shorewall-exclusion</ulink>(5)).</para>
</listitem>
<listitem>
<para>An address range, specified using the syntax
<emphasis>lowaddress</emphasis>-<emphasis>highaddress</emphasis>.</para>
</listitem>
<listitem>
<para>+<replaceable>ipset</replaceable> where
<replaceable>ipset</replaceable> is the name of an ipset
and must be preceded by a plus sign ("+").</para>
</listitem>
<listitem>
<para>^<replaceable>country-code</replaceable> where
country-code is a two-character ISO-3661 country code
preceded by a caret ("^").</para>
</listitem>
<listitem>
<para>^<replaceable>country-code-list</replaceable> where
<replaceable>country-code-list</replaceable> is a
comma-separated list of up to 15 ISO-3661 country codes
enclosed in square brackets ("[...]").</para>
</listitem>
<listitem>
<para>The primary IP address of a firewall interface can
be specified by an ampersand ('&amp;') followed by the
logical name of the interface as found in the INTERFACE
column of <ulink
url="/manpages/shorewall-interfaces.html">shorewall-interfaces</ulink>
(5).</para>
</listitem>
</itemizedlist>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:[!]<replaceable>interface</replaceable>:<replaceable>address</replaceable>[,...]</term>
<listitem>
<para>This form combines the preceding two and requires that
both the outgoing interface and destinationaddress
match.</para>
<para>Beginning with Shorweall 5.2.1, the
<replaceable>interface</replaceable> may be preceded with '!'
which matches all interfaces associated with the zone except
the one specified.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:<replaceable>exclusion</replaceable></term>
<listitem>
<para>This form matches if the host IP address does not match
any of the entries in the exclusion (see <ulink
url="/manpages/shorewall-exclusion.html">shorewall-exclusion</ulink>(5)).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable>zone</replaceable>:[!]<replaceable>interface</replaceable>:<replaceable>exclusion</replaceable></term>
<listitem>
<para>This form matches packets to the named
<replaceable>zone</replaceable> leaving through the specified
<replaceable>interface</replaceable> where the destination
address does not match any entry in the
<replaceable>exclusion</replaceable>.</para>
<para>Beginning with Shorweall 5.2.1, the
<replaceable>interface</replaceable> may be preceded with '!'
which matches all interfaces associated with the zone except
the one specified.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>[<replaceable>zone</replaceable>]:[<replaceable>server-IP</replaceable>][:<replaceable>port-or-port-range</replaceable>[:random]]</term>
<listitem>
<para>This form applies when the ACTION is DNAT[-] or
REDIRECT[-]. The zone may be omitted in REDIRECT rules ($FW is
assumed) and must be omitted in DNAT-, REDIRECT- and NONAT
rules.</para>
<para><replaceable role="bold">server-IP</replaceable> is not
allowed in REDIRECT rules and may be omitted in DNAT[-] rules
provided that <replaceable>port-or-port-range</replaceable> is
included.</para>
<itemizedlist>
<listitem>
<para>The IP address of the server to which the packet is
to be sent.</para>
</listitem>
<listitem>
<para>A range of IP address with the low and high address
separated by a dash (:"-"). Connections are distributed
among the IP addresses in the range.</para>
</listitem>
</itemizedlist>
<para>If <replaceable>server-IP </replaceable>is omitted in a
DNAT[-] rule, only the destination port number is modified by
the rule.</para>
<para>port-or-port-range may be:</para>
<itemizedlist>
<listitem>
<para>An integer port number in the range 1 -
65535.</para>
</listitem>
<listitem>
<para>The name of a service from
<filename>/etc/services</filename>.</para>
</listitem>
<listitem>
<para>A port range with the low and high integer port
numbers separated by a dash ("-"). Connections are
distributed among the ports in the range.</para>
</listitem>
</itemizedlist>
<para>If <emphasis role="bold">random</emphasis> is specified,
port mapping will be randomized.</para>
</listitem>
</varlistentry>
</variablelist>
<para>If the DEST <replaceable>zone</replaceable> is a bport zone,
then either:<orderedlist numeration="loweralpha">
<listitem>
<para>the SOURCE must be <option>all[+]</option>, or</para>
</listitem>
<listitem>
<para>the SOURCE <replaceable>zone</replaceable> must be
another bport zone associated with the same bridge, or</para>
</listitem>
<listitem>
<para>the SOURCE <replaceable>zone</replaceable> must be an
ipv4 zone that is associated with only the same bridge.</para>
</listitem>
</orderedlist>Beginning with Shorewall 5.1.0, multiple
<replaceable>dest-spec</replaceable>s may be listed, provided that
extended forms of the source-spec are used:</para>
<blockquote>
<para><replaceable>zone</replaceable>:(<replaceable>interface</replaceable>)</para>
<para><replaceable>zone</replaceable>:(<replaceable>address</replaceable>[,...])</para>
<para>zone:(interface:address[,...])</para>
<para><replaceable>zone</replaceable>:(<replaceable>exclusion</replaceable>)</para>
<para><replaceable>zone</replaceable>:(<replaceable>interface</replaceable>:<replaceable>exclusion</replaceable>)</para>
</blockquote>
<para>Multiple <replaceable>dest-spec</replaceable>s are not
permitted in DNAT[-] and REDIRECT[-] rules.</para>
<para>Examples:</para>
<variablelist>
<varlistentry>
<term>dmz:192.168.2.2</term>
<listitem>
<para>Host 192.168.2.2 in the DMZ</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:155.186.235.0/24</term>
<listitem>
<para>Subnet 155.186.235.0/24 on the Internet</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:192.168.1.1,192.168.1.2</term>
<listitem>
<para>Hosts 192.168.1.1 and 192.168.1.2 in the local
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:192.0.2.11-192.0.2.17</term>
<listitem>
<para>Hosts 192.0.2.11-192.0.2.17 in the net zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:!192.0.2.11-192.0.2.17</term>
<listitem>
<para>All hosts in the net zone except for
192.0.2.11-192.0.2.17.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:155.186.235.0/24!155.186.235.16/28</term>
<listitem>
<para>Subnet 155.186.235.0/24 on the Internet except for
155.186.235.16/28</para>
</listitem>
</varlistentry>
<varlistentry>
<term>$FW:&amp;eth0</term>
<listitem>
<para>The primary IP address of eth0 in the firewall
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc,dmz</term>
<listitem>
<para>Both the <emphasis role="bold">loc</emphasis> and
<emphasis role="bold">dmz</emphasis> zones.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>all!dmz</term>
<listitem>
<para>All but the <emphasis role="bold">dmz</emphasis>
zone.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>net:^CN</term>
<listitem>
<para>China.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>dmz:192.168.10.4:25</term>
<listitem>
<para>Port 25 on server 192.168.10.4 in the dmz zone (DNAT
rule).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>loc:(eth1:1.2.3.4,2.3.4.5),dmz:(eth2:5.6.7.8,9.10.11.12),net</term>
<listitem>
<para>Hosts 1.2.3.4 and 2.3.4.5 in the loc zone when the
packet arrives through eth1 plus hosts 5.6.7.8 and 9.10.11.12
in the dmz zone when the packet arrives through eth2 plus all
of the net zone.</para>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">PROTO</emphasis>- {<emphasis
role="bold">-</emphasis>|<emphasis
role="bold">tcp:[!]syn</emphasis>|<emphasis
role="bold">ipp2p</emphasis>|<emphasis
role="bold">ipp2p:udp</emphasis>|<emphasis
role="bold">ipp2p:all</emphasis>|<emphasis>protocol-number</emphasis>|<emphasis>protocol-name</emphasis>|<emphasis
role="bold">all}</emphasis></term>
<listitem>
<para>Optional Protocol - <emphasis role="bold">ipp2p</emphasis>*
requires ipp2p match support in your kernel and iptables. <emphasis
role="bold">tcp:syn</emphasis> implies <emphasis
role="bold">tcp</emphasis> plus the SYN flag must be set and the
RST, ACK and FIN flags must be reset. Beginning with Shorewall
5.1.3, you may also specify <emphasis
role="bold">tcp:!syn</emphasis>, which matches if SYN is not set or
if RST, ACK or FIN is set.</para>
<para>Beginning with Shorewall 4.4.19, this column can contain a
comma-separated list of protocol-numbers and/or protocol
names.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DPORT</emphasis> - {<emphasis
role="bold">-</emphasis>|<emphasis>port-name-number-or-range</emphasis>[<emphasis
role="bold">,</emphasis><emphasis>port-name-number-or-range</emphasis>]...|+<replaceable>ipset</replaceable>}</term>
<listitem>
<para>Optional destination Ports. A comma-separated list of Port
names (from services(5)), port numbers or port ranges; if the
protocol is <emphasis role="bold">icmp</emphasis>, this column is
interpreted as the destination icmp-type(s). ICMP types may be
specified as a numeric type, a numeric type and code separated by a
slash (e.g., 3/4), or a typename. See <ulink
url="/configuration_file_basics.htm#ICMP">http://www.shorewall.net/configuration_file_basics.htm#ICMP</ulink>.
Note that prior to Shorewall 4.4.19, only a single ICMP type may be
listed.</para>
<para>If the protocol is <emphasis role="bold">ipp2p</emphasis>,
this column is interpreted as an ipp2p option without the leading
"--" (example <emphasis role="bold">bit</emphasis> for bit-torrent).
If no port is given, <emphasis role="bold">ipp2p</emphasis> is
assumed.</para>
<para>A port range is expressed as
<emphasis>lowport</emphasis>:<emphasis>highport</emphasis>.</para>
<para>This column is ignored if <emphasis
role="bold">PROTO</emphasis> = <emphasis role="bold">all</emphasis>
but must be entered if any of the following columns are supplied. In
that case, it is suggested that this field contain a dash (<emphasis
role="bold">-</emphasis>).</para>
<para>If your kernel contains multi-port match support, then only a
single Netfilter rule will be generated if in this list and the
<emphasis role="bold">SPORT</emphasis> list below:</para>
<para>1. There are 15 or less ports listed.</para>
<para>2. No port ranges are included or your kernel and iptables
contain extended multi-port match support.</para>
<para>Beginning with Shorewall 4.6.0, an
<replaceable>ipset</replaceable> name can be specified in this
column. This is intended to be used with
<firstterm>bitmap:port</firstterm> ipsets.</para>
<para>This column was formerly labelled DEST PORT(S).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SPORT</emphasis> - {<emphasis
role="bold">-</emphasis>|<emphasis>port-name-number-or-range</emphasis>[<emphasis
role="bold">,</emphasis><emphasis>port-name-number-or-range</emphasis>]...|+<replaceable>ipset</replaceable>}</term>
<listitem>
<para>Optional port(s) used by the client. If omitted, any source
port is acceptable. Specified as a comma- separated list of port
names, port numbers or port ranges.</para>
<para>Beginning with Shorewall 4.5.15, you may place '=' in this
column, provided that the DPORT 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). Use of
'=' requires multi-port match in your iptables and kernel.</para>
<warning>
<para>Unless you really understand IP, you should leave this
column empty or place a dash (<emphasis role="bold">-</emphasis>)
in the column. Most people who try to use this column get it
wrong.</para>
</warning>
<para>If you don't want to restrict client ports but need to specify
an <emphasis role="bold">ORIGDEST</emphasis> in the next column,
then place "-" in this column.</para>
<para>If your kernel contains multi-port match support, then only a
single Netfilter rule will be generated if in this list and the
<emphasis role="bold">DPORT</emphasis> list above:</para>
<para>1. There are 15 or less ports listed.</para>
<para>2. No port ranges are included or your kernel and iptables
contain extended multi-port match support.</para>
<para>Beginning with Shorewall 4.6.0, an
<replaceable>ipset</replaceable> name can be specified in this
column. This is intended to be used with
<firstterm>bitmap:port</firstterm> ipsets.</para>
<para>This column was formerly labelled SOURCE PORT(S).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">ORIGDEST</emphasis> - [<emphasis
role="bold">-</emphasis>|<emphasis>address</emphasis>[,<emphasis>address</emphasis>]...[<emphasis>exclusion</emphasis>]|<emphasis>exclusion</emphasis>]</term>
<listitem>
<para>Optional. If ACTION is <emphasis
role="bold">DNAT</emphasis>[<emphasis role="bold">-</emphasis>] or
<emphasis role="bold">REDIRECT</emphasis>[<emphasis
role="bold">-</emphasis>] then if this column is included and is
different from the IP address given in the <emphasis
role="bold">DEST</emphasis> column, then connections destined for
that address will be forwarded to the IP and port specified in the
<emphasis role="bold">DEST</emphasis> column.</para>
<para>A comma-separated list of addresses may also be used. This is
most useful with the <emphasis role="bold">REDIRECT</emphasis>
target where you want to redirect traffic destined for particular
set of hosts. Finally, if the list of addresses begins with "!"
(<emphasis>exclusion</emphasis>) then the rule will be followed only
if the original destination address in the connection request does
not match any of the addresses listed.</para>
<para>Beginning with Shorewall 4.4.17, the primary IP address of a
firewall interface can be specified by an ampersand ('&amp;')
followed by the logical name of the interface as found in the
INTERFACE column of <ulink
url="/manpages/shorewall-interfaces.html">shorewall-interfaces</ulink>
(5).</para>
<para>For other actions, this column may be included and may contain
one or more addresses (host or network) separated by commas. Address
ranges are not allowed. When this column is supplied, rules are
generated that require that the original destination address matches
one of the listed addresses. This feature is most useful when you
want to generate a filter rule that corresponds to a <emphasis
role="bold">DNAT-</emphasis> or <emphasis
role="bold">REDIRECT-</emphasis> rule. In this usage, the list of
addresses should not begin with "!".</para>
<para>It is also possible to specify a set of addresses then exclude
part of those addresses. For example, <emphasis
role="bold">192.168.1.0/24!192.168.1.16/28</emphasis> specifies the
addresses 192.168.1.0-182.168.1.15 and 192.168.1.32-192.168.1.255.
See <ulink
url="/manpages/shorewall-exclusion.html">shorewall-exclusion</ulink>(5).</para>
<para>See <ulink
url="/PortKnocking.html">http://www.shorewall.net/PortKnocking.html</ulink>
for an example of using an entry in this column with a user-defined
action rule.</para>
<para>This column was formerly labelled ORIGINAL DEST.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">RATE</emphasis> -
<replaceable>limit</replaceable></term>
<listitem>
<para>where <replaceable>limit</replaceable> is one of:</para>
<simplelist>
<member>[<emphasis role="bold">-</emphasis>|[{<emphasis
role="bold">s</emphasis>|<emphasis
role="bold">d</emphasis>}[/<replaceable>vlsm</replaceable>]:[<replaceable>name</replaceable>[(<replaceable>ht-buckets</replaceable>,<replaceable>ht-max</replaceable>)]:]<emphasis>rate</emphasis><emphasis
role="bold">/</emphasis>{<emphasis
role="bold">sec</emphasis>|<emphasis
role="bold">min</emphasis>|<emphasis
role="bold">hour</emphasis>|<emphasis
role="bold">day</emphasis>}[:<emphasis>burst</emphasis>]</member>
<member>[<emphasis
role="bold">s</emphasis>[/<replaceable>vlsm1</replaceable>]:][<replaceable>name</replaceable>1[(<replaceable>ht-buckets1</replaceable>,<replaceable>ht-max1</replaceable>)]:]<emphasis>rate1</emphasis><emphasis
role="bold">/</emphasis>{<emphasis
role="bold">sec</emphasis>|<emphasis
role="bold">min</emphasis>|<emphasis
role="bold">hour</emphasis>|<emphasis
role="bold">day</emphasis>}[:<emphasis>burst1</emphasis>],[<emphasis
role="bold">d</emphasis>[/<replaceable>vlsm2</replaceable>:][<replaceable>name</replaceable>2[(<replaceable>ht-buckets2</replaceable>,<replaceable>ht-max2</replaceable>)]:]<emphasis>rate2</emphasis><emphasis
role="bold">/</emphasis>{<emphasis
role="bold">sec</emphasis>|<emphasis
role="bold">min</emphasis>|<emphasis
role="bold">hour</emphasis>|<emphasis
role="bold">day</emphasis>}[:<emphasis>burst2</emphasis>]</member>
</simplelist>
<para>You may optionally rate-limit the rule by placing a value in
this column:</para>
<para><emphasis>rate*</emphasis> is the number of connections per
interval (<emphasis role="bold">sec</emphasis> or <emphasis
role="bold">min</emphasis>) and <emphasis>burst</emphasis>* is the
largest burst permitted. If no <emphasis>burst</emphasis> is given,
a value of 5 is assumed. There may be no no white-space embedded in
the specification.</para>
<para>Example: <emphasis role="bold">10/sec:20</emphasis></para>
<para>When <option>s:</option> or <option>d:</option> is specified,
the rate applies per source IP address or per destination IP address
respectively. The <replaceable>name</replaceable>s may be chosen by
the user and specify a hash table to be used to count matching
connections. If not given, the name <emphasis
role="bold">shorewallN</emphasis> (where N is a unique integer) is
assumed. Where more than one rule or POLICY specifies the same name,
the connections counts for the rules are aggregated and the
individual rates apply to the aggregated count. Beginning with
Shorewall 5.2.1, the <emphasis role="bold">s</emphasis> or <emphasis
role="bold">d</emphasis> may be followed by a slash ("/") and an
integer <replaceable>vlsm</replaceable>. When a
<replaceable>vlsm</replaceable> is specified, all source or
destination addresses encountered will be grouped according to the
given prefix length and the so-created subnet will be subject to the
rate limit.</para>
<para>Example: <emphasis role="bold">s/24::10/sec</emphasis></para>
<para>Beginning with Shorewall 4.6.5, two<replaceable>
limit</replaceable>s may be specified, separated by a comma. In this
case, the first limit (<replaceable>name1</replaceable>,
<replaceable>rate1</replaceable>, burst1) specifies the per-source
IP limit and the second limit specifies the per-destination IP
limit.</para>
<para>Example: <emphasis
role="bold">client:10/sec:20,:60/sec:100</emphasis></para>
<para>In this example, the 'client' hash table will be used to
enforce the per-source limit and the compiler will pick a unique
name for the hash table that tracks the per-destination
limit.</para>
<para>Beginning with Shorewall 5.2.1, the table name, if any, may be
followed by two integers separated by commas and enclosed in
parentheses. The first integer
(<replaceable>ht-buckets</replaceable>) specifies the number of
buckets in the generated hash table. The second integer
(<replaceable>ht-max</replaceable>) specifies the maximum number of
entries in the hash table.</para>
<para>Example: <emphasis
role="bold">s:netfw(1024,65536):10/sec</emphasis></para>
<para>This column was formerly labelled RATE LIMIT.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">USER</emphasis> - [<emphasis
role="bold">!</emphasis>][<emphasis>user-name-or-number</emphasis>][<emphasis
role="bold">:</emphasis><emphasis>group-name-or-number</emphasis>][,...]</term>
<listitem>
<para>This optional column may only be non-empty if the SOURCE is
the firewall itself.</para>
<para>When this column is non-empty, the rule applies only if the
program generating the output is running under the effective
<emphasis>user</emphasis> and/or <emphasis>group</emphasis>
specified (or is NOT running under that id if "!" is given).</para>
<para>Beginning with Shorewall 4.5.8, multiple user or group
names/ids separated by commas may be specified.</para>
<para>Examples:</para>
<variablelist>
<varlistentry>
<term>joe</term>
<listitem>
<para>program must be run by joe</para>
</listitem>
</varlistentry>
<varlistentry>
<term>:kids</term>
<listitem>
<para>program must be run by a member of the 'kids'
group</para>
</listitem>
</varlistentry>
<varlistentry>
<term>!:kids</term>
<listitem>
<para>program must not be run by a member of the 'kids'
group</para>
</listitem>
</varlistentry>
<varlistentry>
<term>2001-2099</term>
<listitem>
<para>UIDs 2001 through 2099 (Shorewall 4.5.6 and
later)</para>
</listitem>
</varlistentry>
</variablelist>
<para>This column was formerly labelled USER/GROUP.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">MARK</emphasis> - [<emphasis
role="bold">!</emphasis>]<emphasis>value</emphasis>[/<emphasis>mask</emphasis>][<emphasis
role="bold">:C</emphasis>]</term>
<listitem>
<para>Defines a test on the existing packet or connection mark. The
rule will match only if the test returns true.</para>
<para>If you don't want to define a test but need to specify
anything in the following columns, place a "-" in this field.</para>
<variablelist>
<varlistentry>
<term>!</term>
<listitem>
<para>Inverts the test (not equal)</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis>value</emphasis></term>
<listitem>
<para>Value of the packet or connection mark.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis>mask</emphasis></term>
<listitem>
<para>A mask to be applied to the mark before testing.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">:C</emphasis></term>
<listitem>
<para>Designates a connection mark. If omitted, the packet
mark's value is tested.</para>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">CONNLIMIT</emphasis> - [d:][<emphasis
role="bold">!</emphasis>]<emphasis>limit</emphasis>[:<emphasis>mask</emphasis>]</term>
<listitem>
<para>May be used to limit the number of simultaneous connections
to/from each individual host or network to
<replaceable>limit</replaceable> connections. Requires connlimit
match in your kernel and iptables. While the limit is only checked
on rules specifying CONNLIMIT, the number of current connections is
calculated over all current connections from the SOURCE or
DESTINATION host. By default, limiting is done by SOURCE host or
net, but if the specification begins with <emphasis
role="bold">d:</emphasis>, then limiting will be donw by destination
host or net.</para>
<para>By default, the limit is applied to each host but can be made
to apply to networks of hosts by specifying a
<replaceable>mask</replaceable>. The <replaceable>mask</replaceable>
specifies the width of a VLSM mask to be applied to the source
address; the number of current connections is then taken over all
hosts in the subnet
<replaceable>source-address</replaceable>/<replaceable>mask</replaceable>.
When<option> !</option> is specified, the rule matches when the
number of connection exceeds the
<replaceable>limit</replaceable>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">TIME</emphasis> -
<emphasis>timeelement</emphasis>[&amp;<emphasis>timeelement</emphasis>...]</term>
<listitem>
<para>May be used to limit the rule to a particular time period each
day, to particular days of the week or month, or to a range defined
by dates and times. Requires time match support in your kernel and
iptables.</para>
<para><replaceable>timeelement</replaceable> may be:</para>
<variablelist>
<varlistentry>
<term>timestart=<replaceable>hh</replaceable>:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]</term>
<listitem>
<para>Defines the starting time of day.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>timestop=<replaceable>hh</replaceable>:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]</term>
<listitem>
<para>Defines the ending time of day.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>contiguous</term>
<listitem>
<para>Added in Shoreawll 5.0.12. When <emphasis
role="bold">timestop</emphasis> is smaller than <emphasis
role="bold">timestart</emphasis> value, match this as a single
time period instead of distinct intervals.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>utc</term>
<listitem>
<para>Times are expressed in Greenwich Mean Time.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>localtz</term>
<listitem>
<para>Deprecated by the Netfilter team in favor of <emphasis
role="bold">kerneltz</emphasis>. Times are expressed in Local
Civil Time (default).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>kerneltz</term>
<listitem>
<para>Added in Shorewall 4.5.2. Times are expressed in Local
Kernel Time (requires iptables 1.4.12 or later).</para>
</listitem>
</varlistentry>
<varlistentry>
<term>weekdays=ddd[,ddd]...</term>
<listitem>
<para>where <replaceable>ddd</replaceable> is one of
<option>Mon</option>, <option>Tue</option>,
<option>Wed</option>, <option>Thu</option>,
<option>Fri</option>, <option>Sat</option> or
<option>Sun</option></para>
</listitem>
</varlistentry>
<varlistentry>
<term>monthdays=dd[,dd],...</term>
<listitem>
<para>where <replaceable>dd</replaceable> is an ordinal day of
the month</para>
<para/>
</listitem>
</varlistentry>
<varlistentry>
<term>datestart=<replaceable>yyyy</replaceable>[-<replaceable>mm</replaceable>[-<replaceable>dd</replaceable>[<option>T</option><replaceable>hh</replaceable>[:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]]]]]</term>
<listitem>
<para>Defines the starting date and time.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>datestop=<replaceable>yyyy</replaceable>[-<replaceable>mm</replaceable>[-<replaceable>dd</replaceable>[<option>T</option><replaceable>hh</replaceable>[:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]]]]]</term>
<listitem>
<para>Defines the ending date and time.</para>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">HEADERS -
[!][any:|exactly:]</emphasis><replaceable>header-list
</replaceable>(Optional - Added in Shorewall 4.4.15)</term>
<listitem>
<para>This column is only used in IPv6. In IPv4, supply "-" in this
column if you with to place a value in one of the following
columns.</para>
<para>The <replaceable>header-list</replaceable> consists of a
comma-separated list of headers from the following list.</para>
<variablelist>
<varlistentry>
<term><emphasis role="bold">auth</emphasis>, <emphasis
role="bold">ah</emphasis>, or <emphasis
role="bold">51</emphasis></term>
<listitem>
<para><firstterm>Authentication Headers</firstterm> extension
header.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">esp</emphasis>, or <emphasis
role="bold">50</emphasis></term>
<listitem>
<para><firstterm>Encrypted Security Payload</firstterm>
extension header.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">hop</emphasis>, <emphasis
role="bold">hop-by-hop</emphasis> or <emphasis
role="bold">0</emphasis></term>
<listitem>
<para>Hop-by-hop options extension header.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">route</emphasis>, <emphasis
role="bold">ipv6-route</emphasis> or <emphasis
role="bold">43</emphasis></term>
<listitem>
<para>IPv6 Route extension header.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">frag</emphasis>, <emphasis
role="bold">ipv6-frag</emphasis> or <emphasis
role="bold">44</emphasis></term>
<listitem>
<para>IPv6 fragmentation extension header.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">none</emphasis>, <emphasis
role="bold">ipv6-nonxt</emphasis> or <emphasis
role="bold">59</emphasis></term>
<listitem>
<para>No next header</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">proto</emphasis>, <emphasis
role="bold">protocol</emphasis> or <emphasis
role="bold">255</emphasis></term>
<listitem>
<para>Any protocol header.</para>
</listitem>
</varlistentry>
</variablelist>
<para>If <emphasis role="bold">any:</emphasis> is specified, the
rule will match if any of the listed headers are present. If
<emphasis role="bold">exactly:</emphasis> is specified, the will
match packets that exactly include all specified headers. If neither
is given, <emphasis role="bold">any:</emphasis> is assumed.</para>
<para>If <emphasis role="bold">!</emphasis> is entered, the rule
will match those packets which would not be matched when <emphasis
role="bold">!</emphasis> is omitted.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SWITCH -
[!]<replaceable>switch-name</replaceable>[={0|1}]</emphasis></term>
<listitem>
<para>Added in Shorewall 4.4.24 and allows enabling and disabling
the rule without requiring <command>shorewall
restart</command>.</para>
<para>The rule is enabled if the value stored in
<filename>/proc/net/nf_condition/<replaceable>switch-name</replaceable></filename>
is 1. The rule is disabled 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>shorewall
restart</command>.</para>
<para>Beginning with Shorewall 4.5.10, 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>
<varlistentry>
<term><emphasis role="bold">HELPER</emphasis> - [helper]</term>
<listitem>
<para>Added in Shorewall 4.5.7.</para>
<para>In the NEW section, causes the named conntrack
<replaceable>helper</replaceable> to be associated with this
connection; the contents of this column are ignored unless ACTION is
ACCEPT*, DNAT* or REDIRECT*.</para>
<para>In the RELATED section, will only match if the related
connection has the named <replaceable>helper</replaceable>
associated with it.</para>
<para>The <replaceable>helper</replaceable> may be one of:</para>
<simplelist>
<member><option>amanda</option></member>
<member><option>ftp</option></member>
<member><option>irc</option></member>
<member><option>netbios-ns</option></member>
<member><option>pptp</option></member>
<member><option>Q.931</option></member>
<member><option>RAS</option></member>
<member><option>sane</option></member>
<member><option>sip</option></member>
<member><option>snmp</option></member>
<member><option>tftp</option></member>
</simplelist>
<para>If the HELPERS option is specified in <ulink
url="/manpages/shorewall.conf.html">shorewall.conf</ulink>(5), then
any module specified in this column must be listed in the HELPERS
setting.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Examples</title>
<variablelist>
<varlistentry>
<term>Example 1:</term>
<listitem>
<para>Accept SMTP requests from the DMZ to the internet</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
ACCEPT dmz net tcp smtp</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 2:</term>
<listitem>
<para>Forward all ssh and http connection requests from the internet
to local system 192.168.1.3</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
DNAT net loc:192.168.1.3 tcp ssh,http</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 3:</term>
<listitem>
<para>Forward all http connection requests from the internet to
local system 192.168.1.3 with a limit of 3 per second and a maximum
burst of 10<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST RATE
DNAT net loc:192.168.1.3 tcp http - - 3/sec:10</programlisting></para>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 4:</term>
<listitem>
<para>Redirect all locally-originating www connection requests to
port 3128 on the firewall (Squid running on the firewall system)
except when the destination address is 192.168.2.2</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
REDIRECT loc 3128 tcp www - !192.168.2.2</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 5:</term>
<listitem>
<para>All http requests from the internet to address 130.252.100.69
are to be forwarded to 192.168.1.3</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
DNAT net loc:192.168.1.3 tcp 80 - 130.252.100.69</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 6:</term>
<listitem>
<para>You want to accept SSH connections to your firewall only from
internet IP addresses 130.252.100.69 and 130.252.100.70</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
ACCEPT net:130.252.100.69,130.252.100.70 \
$FW tcp 22</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 7:</term>
<listitem>
<para>You wish to accept connections from the internet to your
firewall on port 2222 and you want to forward them to local system
192.168.1.3, port 22</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
DNAT net loc:192.168.1.3:22 tcp 2222</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 8:</term>
<listitem>
<para>You want to redirect connection requests to port 80 randomly
to the port range 81-90.</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
REDIRECT net $FW::81-90:random tcp www</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 9:</term>
<listitem>
<para>Shorewall does not impose as much structure on the Netfilter
rules in the 'nat' table as it does on those in the filter table. As
a consequence, when using Shorewall versions before 4.1.4, care must
be exercised when using DNAT and REDIRECT rules with zones defined
with wildcard interfaces (those ending with '+'. Here is an
example:</para>
<para><ulink
url="/manpages/shorewall-zones.html">shorewall-zones</ulink>(5):<programlisting> #ZONE TYPE OPTIONS
fw firewall
net ipv4
dmz ipv4
loc ipv4</programlisting></para>
<para><ulink
url="/manpages/shorewall-interfaces.html">shorewall-interfaces</ulink>(5):<programlisting> #ZONE INTERFACE BROADCAST OPTIONS
net ppp0
loc eth1 detect
dmz eth2 detect
- ppp+ # Addresses are assigned from 192.168.3.0/24</programlisting></para>
<para><ulink
url="/manpages/shorewall-hosts.html">shorewall-host</ulink>(5):<programlisting> #ZONE HOST(S) OPTIONS
loc ppp+:192.168.3.0/24</programlisting></para>
<para>rules:</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT
REDIRECT loc 3128 tcp 80 </programlisting>
<simpara>Note that it would have been tempting to simply define the
loc zone entirely in shorewall-interfaces(8):</simpara>
<para><programlisting> #******************* INCORRECT *****************
#ZONE INTERFACE BROADCAST OPTIONS
net ppp0
loc eth1 detect
loc ppp+
dmz eth2</programlisting></para>
<para>This would have made it impossible to run a
internet-accessible web server in the DMZ because all traffic
entering ppp+ interfaces would have been redirected to port 3128 on
the firewall and there would have been no net-&gt;fw ACCEPT rule for
that traffic.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 10:</term>
<listitem>
<para>Add the tuple (source IP, dest port, dest IP) of an incoming
SSH connection to the ipset S:</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT
ADD(+S:dst,src,dst) net fw tcp 22</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 11:</term>
<listitem>
<para>You wish to limit SSH connections from remote systems to 1/min
with a burst of three (to allow for limited retry):</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST RATE
SSH(ACCEPT) net all - - - - s:1/min:3</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 12:</term>
<listitem>
<para>Forward port 80 to dmz host $BACKUP if switch 'primary_down'
is on.</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST RATE USER MARK CONNLIMIT TIME HEADERS SWITCH
DNAT net dmz:$BACKUP tcp 80 - - - - - - - - primary_down</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 13:</term>
<listitem>
<para>Drop all email from the <emphasis>Anonymous Proxy</emphasis>
and <emphasis>Satellite Provider</emphasis> address ranges:</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT
DROP net:^A1,A2 fw tcp 25</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 14:</term>
<listitem>
<para>You want to generate your own rule involving iptables targets
and matches not supported by Shorewall.</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT
INLINE $FW net ; -p 6 -m mickey-mouse --name test -m set --match-set set1 src -m mickey-mouse --name test2 -j SECCTX --name test3</programlisting>
<para>The above will generate the following iptables-restore
input:</para>
<programlisting> -A fw2net -p 6 -m mickey-mouse --name test -m set --match-set set1 src -m mickey-mouse --name test2 -j SECCTX --name test3</programlisting>
<para>Note that SECCTX must be defined as a builtin action in <ulink
url="/manpages/shorewall-actions.html">shorewall-actions</ulink>(5):</para>
<programlisting> #ACTION OPTIONS
SECCTX builtin</programlisting>
</listitem>
</varlistentry>
<varlistentry>
<term>Example 15:</term>
<listitem>
<para>You want to accept SSH connections to your firewall only from
internet IP addresses 2002:ce7c::92b4:1::2 and
2002:ce7c::92b4:1::22</para>
<programlisting> #ACTION SOURCE DEST PROTO DPORT SPORT ORIGDEST
ACCEPT net:&lt;2002:ce7c::92b4:1::2,2002:ce7c::92b4:1::22&gt; \
$FW tcp 22</programlisting>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>FILES</title>
<para>/etc/shorewall/rules</para>
<para>/etc/shorewall6/rules</para>
</refsect1>
<refsect1>
<title>See ALSO</title>
<para><ulink
url="shorewall-logging.html">shorewall-logging(5)</ulink></para>
<para><ulink
url="/ipsets.html">http://www.shorewall.net/ipsets.html</ulink></para>
<para><ulink
url="/configuration_file_basics.htm#Pairs">http://www.shorewall.net/configuration_file_basics.htm#Pairs</ulink></para>
<para>shorewall(8)</para>
</refsect1>
</refentry>
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