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     First of all, the syntax of this configuration file is far from being
     perfect. If you’ve got some better ideas just drop me a line...
     /etc/uif/uif.conf is the default configuration file for uif(8).  This
     file may contain several sections and comments. Each section begins with
     the section name and the left curly brace and ends with the right curly
     brace in a single line. A comment starts with a hash mark (#) at the
     beginning of a line.

     Blank lines are silently ignored. The following sections are valid:
     include, sysconfig, service, network, interface, marker, filter, nat,
     input, output, forward, masquerade and stateless.

     The sections service, network, marker and interface have all a very
     similar syntax.  Each line starts with an identifier followed by one or
     more blanks and one or more section specific entries or defined
     identifiers separated by blanks.  A valid identifier is case sensitive
     and consists of letters, digits, underscores and hyphens.

     If two or more identifiers in one section are equal, the corresponding
     entries are merged to the first identifier. Hence, it’s not possible to
     overwrite perviously defined identifiers. As a result the order of the
     section entries is irrelevant and it’s possible to define a section more
     than once.

   include section
     Include other configuration files. Each line in this section, enclosed in
     quotation marks ("), must be a valid filename. The contents of this file
     are added to the actual configuration file and each file should contain
     at least one section (a comment only file is not really useful...).

   sysconfig section
     Set some global settings. Each line in this section starts with one of
     the following identifiers followed by one or more blanks and the desired
     value: LogLevel, LogPrefix, LogLimit, LogBurst, Limit, Burst and
     AccountPrefix. If there are multiple definitions of one entry the last
     definition is stored.

             A valid default log priority (see syslog.conf(5))

             The default log prefix. Each iptables logmessage starts with this

             The default limit value for logmessages (see iptables(8))

             The default burst value for logmessages (see iptables(8))

     Limit   The default limit value (see iptables(8))

     Burst   The default burst value (see iptables(8))

             The default prefix for accounting chains.

   service section
     This section defines all needed services. A service description starts
     with the protocol (see protocols(5)) followed by parameters in
     parenthesis. Most protocols don’t need any parameters. The only
     exceptions are tcp, udp and icmp. The tcp and udp parameter defines the
     source and destionation port(-range). The source and destination ports
     are separated by a slash (/) and portranges are separated by a colon (eg.
     tcp(123:333/99): tcp protocol, source-portrange 123-333, destination port
     99). Empty source or destination ports are expanded to 1:65535. The icmp
     protocol parameter must be a valid icmp type (see iptables -p icmp

   network section
     This section defines all needed networks and hosts. A network description
     starts with a valid IPv4 address (dotted quad), an optional netmask in
     cidr notation (number of bits) or an optional MAC-address (with a
     prefixed equal sign (=). Some valid entries are:

   interface section
     This section defines all needed (physical and bridged) interfaces (eg.
     eth0, lo, ppp0).

   marker section
     This section defines all needed numerical (decimal) values for packet
     marking purposes.

   filter, nat, input, output, forward, masquerade and stateless sections
     Due to better partitioning of the packetfilter, rules can be split into
     these sections. Internally they are equivalent and contain all rules. As
     an exception to all other sections the order of entries in these sections
     is important.

     The default policy for the chains INPUT, OUTPUT and FORWARD is DROP (see
     iptables(8)) and it’s not possible to change this.

     Each line in in this section begins with in, out, fw, nat, masq, slin,
     slout or slfw followed by ’+’, ’-’ or a mark identifier enclosed in curly
     braces (or, in case of fw followed by ’>’).  The identifiers in, out and
     fw define rules for incoming, outgoing and forwarded IP-packets. Each
     packet with an INVALID state (see iptables(8)) is matched by slin, slout
     and slfw. The lines starting with nat and masq define rules to modify the
     source or destination address or the destination port.

     The plus and minus signs specify the type of the rule: ’+’ accepts
     matching packets and ’-’ drops them. As a special case the identifier out
     and fw accept the greater than (>) sign to modify the MSS depending on
     the PMTU (see iptables(8))

     A very basic ruleset may look like this: out+

     This allows every outgoing traffic and rejects all incoming connections
     (because of the default policy).

     To be more specific, each line may contain several parameters. Each
     parameter starts with a single character followed by an equal sign (=)
     and one or more previously defined identifiers (in the corresponding
     sections) separated by commas. The following parameters are valid:

     s       The source address or network.

     d       The destination address or network.

     i       The input interface.

     o       The output interface.

     pi      The physical input interface (only useful when used with bridged

     po      The physical output interface (only useful when used with bridged

     p       The service description (protocol).

     m       The mark field associated with a packet.

     S       The the new source address in nat rules.

     D       The the new destination address in nat rules.

     P       The the new service description in nat rules. This is only valid
             with tcp or udp packets.

     f       This parameter sets some ’flags’. A flag definition starts with
             the flag identifier and optional parameters in parenthesis. Valid
             flags are:

             log - Logs matching packages to syslog. The given parameter is
             included in the log entry. The number of logged packets and the
             loglevel can be set in the sysconfig section.

             reject - Only valid in DROP rules. This is used to send back an
             error packet in response to the matched packet. The default
             behaviour is a packet with set RST flag on tcp connections and a
             destination-unreachable icmp packet in every other case. Valid
             parameters are listed in iptables(8) in the REJECT section.

             account - Create an accounting chain for all matching packages
             and possible responses.  The optional parameter is a part of the
             name of the chain.

             limit - Limits the number of matching packets. The default values
             are set in the sysconfig section. Other values can be defined
             with the optional parameter.  The first entry sets a new limit
             and the second parameter (separated by a comma (,)) sets the
             burst value (see Limit and Burst in sysconfig section).

     It’s possible to invert the identifier of one of following parameters -
     if it expands to ecactly one object - by prepending a exclamation mark
     (!): s, d, i, o, p (eg.: s=!local p=!http).


     Configuration files are located in /etc/uif. There is a sample
     configuration in /usr/share/doc/uif/uif.conf.tmpl.gz.


     iptables(8) uif(8)


     This manual page was written by Jörg Platte <> and
     Cajus Pollmeier <>, for the Debian GNU/Linux system
     (but may be used by others).