shorewall_code/manpages/shorewall-rules.xml
2006-11-15 23:32:14 +00:00

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<?xml version="1.0" encoding="UTF-8"?>
<refentry>
<refmeta>
<refentrytitle>shorewall-rules</refentrytitle>
<manvolnum>5</manvolnum>
</refmeta>
<refnamediv>
<refname>rules</refname>
<refpurpose>Shorewall rules file</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>/etc/shorewall/rules</command>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>Rules in this file govern connection establishment. 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 match is the one
that determines the disposition of the request.</para>
<para>In most places where an IP address or subnet is allowed, you can
preceed the address/subnet with "!" (e.g., !192.168.1.0/24) to indicate
that the rule matches all addresses except the address/subnet given.
Notice that no white space is permitted between "!" and the
address/subnet.</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 *must* 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 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">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 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 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">NEW</emphasis></term>
<listitem>
<para>Packets in the NEW and INVALID states are processed by rules
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 I suggest that you omit the <emphasis
role="bold">ESTABLISHED</emphasis> and <emphasis
role="bold">RELATED</emphasis> sections and 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 shorewall.conf(5) then the
<emphasis role="bold">ESTABLISHED</emphasis> and <emphasis
role="bold">RELATED</emphasis> sections must be empty.</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>The columns in the file are as follows.</para>
<variablelist>
<varlistentry>
<term><emphasis role="bold">ACTION</emphasis></term>
<listitem>
<para>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 <emphasis role="bold">DNAT</emphasis>[<emphasis
role="bold">-</emphasis>] or <emphasis
role="bold">REDIRECT</emphasis>[<emphasis
role="bold">-</emphasis>] rules</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.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DROP</emphasis></term>
<listitem>
<para>Ignore the request.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">REJECT</emphasis></term>
<listitem>
<para>disallow the request and return an icmp-unreachable or
an RST packet.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DNAT</emphasis></term>
<listitem>
<para>Forward the request to another system (and optionally
another port).</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.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SAME</emphasis></term>
<listitem>
<para>Similar to <emphasis role="bold">DNAT</emphasis> except
that the port may not be remapped and when multiple server
addresses are listed, all requests from a given remote system
go to the same server.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SAME-</emphasis></term>
<listitem>
<para>Advanced users only.</para>
<para>Like SAME but only generates the NAT iptables rule and
not the companion <emphasis role="bold">ACCEPT</emphasis>
rule.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">REDIRECT</emphasis></term>
<listitem>
<para>Redirect the request to a server on the firewall.</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.</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
shorewall-zones(5), this connection request will be passed to
the rules defined for that (those) zone(s).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">LOG</emphasis></term>
<listitem>
<para>Simply log the packet and continue.</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).</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 entres. 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>action</emphasis></term>
<listitem>
<para>The name of an <emphasis>action</emphasis> defined in
shorewall-actions(5) or in
/usr/share/shorewall/actions.std.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis>macro</emphasis></term>
<listitem>
<para>The name of a macro defined in a file named macro.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 "/" and the
action (<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>
</listitem>
</varlistentry>
</variablelist>
<para>The <emphasis role="bold">ACTION</emphasis> may optionally be
followed by ":" and a syslog log level (e.g, REJECT:info or
DNAT:debug). This causes the packet to be logged at the specified
level.</para>
<para>If the <emphasis role="bold">ACTION</emphasis> names an
<emphasis>action</emphasis> defined in shorewall-actions(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 'none!' suppresses logging by the
action.</para>
</listitem>
</itemizedlist>
<para>You may also specify ULOG (must be in upper case) as a log
level.This will log to the ULOG target for routing to a separate log
through use of ulogd
(http://www.gnumonks.org/projects/ulogd).</para>
<para>Actions specifying logging may be followed by a log tag (a
string of alphanumeric characters) are appended to the string
generated by the LOGPREFIX (in shorewall.conf(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</emphasis></term>
<listitem>
<para>Source hosts to which the rule applies. May be a zone defined
in /etc/shorewall/zones, <emphasis role="bold">$FW</emphasis> to
indicate the firewall itself, <emphasis role="bold">all</emphasis>,
<emphasis role="bold">all+</emphasis>, <emphasis
role="bold">all-</emphasis>, <emphasis role="bold">all+-</emphasis>
or <emphasis role="bold">none</emphasis>.</para>
<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>
<para><emphasis role="bold">all</emphasis> means "All Zones",
including the firewall itself. <emphasis role="bold">all-</emphasis>
means "All Zones, except the firewall itself". When <emphasis
role="bold">all</emphasis>[<emphasis role="bold">-</emphasis>] is
used either in the <emphasis role="bold">SOURCE</emphasis> or
<emphasis role="bold">DEST</emphasis> column intra-zone traffic is
not affected. When <emphasis role="bold">all+</emphasis>[<emphasis
role="bold">-</emphasis>] is "used, intra-zone traffic is
affected.</para>
<para>Except when <emphasis role="bold">all</emphasis>[<emphasis
role="bold">+</emphasis>][<emphasis role="bold">-</emphasis>] is
specified, clients may be further restricted to a list of subnets
and/or hosts by appending ":" and a comma-separated list of subnets
and/or hosts. Hosts may be specified by IP or MAC address; mac
addresses must begin with "~" and must use "-" as a
separator.</para>
<para>Hosts may be specified as an IP address range using the syntax
<emphasis>lowaddress</emphasis>-<emphasis>highaddress</emphasis>.
This requires that your kernel and iptables contain iprange match
support. If you kernel and iptables have ipset match support then
you may give the name of an ipset prefaced by "+". The ipset name
may be optionally followed by a number from 1 to 6 enclosed in
square brackets ([]) to indicate the number of levels of source
bindings to be matched.</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>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>
</variablelist>
<para>Alternatively, clients may be specified by interface by
appending ":" to the zone name followed by the interface name. For
example, loc:eth1 specifies a client that communicates with the
firewall system through eth1. This may be optionally followed by
another colon (":") and an IP/MAC/subnet address as described above
(e.g., loc:eth1:192.168.1.5).</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DEST</emphasis></term>
<listitem>
<para>Location of Server. May be a zone defined in
shorewall-zones(5), $<emphasis role="bold">FW</emphasis> to indicate
the firewall itself, <emphasis role="bold">all</emphasis>. <emphasis
role="bold">all+</emphasis> or <emphasis
role="bold">none</emphasis>.</para>
<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>
<para>When <emphasis role="bold">all</emphasis> is used either in
the <emphasis role="bold">SOURCE</emphasis> or <emphasis
role="bold">DEST</emphasis> column intra-zone traffic is not
affected. When <emphasis role="bold">all+</emphasis> is used,
intra-zone traffic is affected.</para>
<para>Except when <emphasis role="bold">all</emphasis>[<emphasis
role="bold">+</emphasis>] is specified, the server may be further
restricted to a particular subnet, host or interface by appending
":" and the subnet, host or interface. See above.</para>
<para>Restrictions:</para>
<para>1. MAC addresses are not allowed.</para>
<para>2. In <emphasis role="bold">DNAT</emphasis> rules, only IP
addresses are allowed; no FQDNs or subnet addresses are
permitted.</para>
<para>3. You may not specify both an interface and an
address.</para>
<para>Like in the <emphasis role="bold">SOURCE</emphasis> column,
you may specify a range of IP addresses using the syntax
<emphasis>lowaddress</emphasis>-<emphasis>highaddress</emphasis>.
When the <emphasis role="bold">ACTION</emphasis> is <emphasis
role="bold">DNAT</emphasis> or <emphasis
role="bold">DNAT-</emphasis>, the connections will be assigned to
addresses in the range in a round-robin fashion.</para>
<para>If you kernel and iptables have ipset match support then you
may give the name of an ipset prefaced by "+". The ipset name may be
optionally followed by a number from 1 to 6 enclosed in square
brackets ([]) to indicate the number of levels of destination
bindings to be matched. Only one of the <emphasis
role="bold">SOURCE</emphasis> and <emphasis
role="bold">DEST</emphasis> columns may specify an ipset
name.</para>
<para>The port that the server is listening on may be included and
separated from the server's IP address by ":". If omitted, the
firewall will not modifiy the destination port. A destination port
may only be included if the <emphasis role="bold">ACTION</emphasis>
is <emphasis role="bold">DNAT</emphasis> or <emphasis
role="bold">REDIRECT</emphasis>. Example: </para>
<variablelist>
<varlistentry>
<term>Example:</term>
<listitem>
<para>"loc:192.168.1.3:3128" specifies a local server at IP
address 192.168.1.3 and listening on port 3128. The port
number MUST be specified as an integer and not as a name from
services(5).</para>
</listitem>
</varlistentry>
</variablelist>
<para>if the <emphasis role="bold">ACTION</emphasis> is <emphasis
role="bold">REDIRECT</emphasis>, this column needs only to contain
the port number on the firewall that the request should be
redirected to.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">PROTO</emphasis> (Optional)</term>
<listitem>
<para>Protocol - Must be <emphasis role="bold">tcp</emphasis>,
<emphasis role="bold">tcp:syn</emphasis>, <emphasis
role="bold">udp</emphasis>, <emphasis role="bold">icmp</emphasis>,
<emphasis role="bold">ipp2p</emphasis>,<emphasis role="bold">
ipp2p:udp</emphasis>, <emphasis role="bold">ipp2p:all</emphasis> a
<emphasis>number</emphasis>, or <emphasis
role="bold">all</emphasis>. <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.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">DEST PORT(S) </emphasis>(Optional)</term>
<listitem>
<para>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).</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">CLIENT PORT(S)</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 multiport match support.</para>
<para>Otherwise, a separate rule will be generated for each
port.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">SOURCE PORT(S)</emphasis>
(Optional)</term>
<listitem>
<para>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>
<warning>
<para>Unless you really understand TCP/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">ORIGINAL DEST</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">DEST PORT(S)</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 multiport match support.</para>
<para>Otherwise, a separate rule will be generated for each
port.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">ORIGINAL DEST</emphasis> (Optional)</term>
<listitem>
<para>If ACTION is <emphasis role="bold">DNAT</emphasis>[<emphasis
role="bold">-</emphasis>] or <emphasis
role="bold">REDIRECT</emphasis>[<emphasis role="bold">-</emphasis>]
then if included and different from the IP address given in the
<emphasis role="bold">SERVER</emphasis> column, this is an address
on some interface on the firewall and connections to 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
usually 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 "!" 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>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>See http://shorewall.net/PortKnocking.html for an example of
using an entry in this column with a user-defined action
rule.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">RATE LIMIT</emphasis> (Optional)</term>
<listitem>
<para>You may rate-limit the rule by placing a value in this column:
</para>
<para><emphasis>rate</emphasis>/<emphasis>interval</emphasis>[:<emphasis>burst</emphasis>]
where <emphasis>rate</emphasis> is the number of connections per
<emphasis>interval</emphasis> (<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 whitespace embedded in the specification.</para>
<para>Example: 10/sec:20</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis role="bold">USER/GROUP</emphasis> (Optional)</term>
<listitem>
<para>This column may only be non-empty if the SOURCE is the
firewall itself.</para>
<para>The column may contain:</para>
<para>[!][<emphasis>user name or number</emphasis>][:<emphasis>group
name or number</emphasis>][+<emphasis>program name</emphasis>]
</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>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>+upnpd</term>
<listitem>
<para>#program named upnpd</para>
<important>
<para>The ability to specify a program name was removed from
Netfilter in kernel version 2.6.14.</para>
</important>
</listitem>
</varlistentry>
</variablelist>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Example</title>
<variablelist>
<varlistentry>
<term>Example 1:</term>
<listitem>
<para>Accept SMTP requests from the DMZ to the internet</para>
<programlisting> #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
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 DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
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 DEST SOURCE ORIGINAL RATE
# PORT PORT(S) DEST LIMIT
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 DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
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 DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
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 DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
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 DEST SOURCE ORIGINAL
# PORT PORT(S) DEST
ACCEPT net loc:192.168.1.3:22 tcp 2222</programlisting>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>FILES</title>
<para>/etc/shorewall/rules</para>
</refsect1>
<refsect1>
<title>See ALSO</title>
<para>shorewall(8), shorewall-accounting(5), shorewall-actions(5),
shorewall-blacklist(5), shorewall-hosts(5), shorewall-interfaces(5),
shorewall-ipsec(5), shorewall-maclist(5), shorewall-masq(5),
shorewall-nat(5), shorewall-netmap(5), shorewall-params(5),
shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5),
shorewall-route_routes(5), shorewall-routestopped(5), shorewall.conf(5),
shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-tcrules(5),
shorewall-tos(5), shorewall-tunnels(5), shorewall-zones(5)</para>
</refsect1>
</refentry>