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diff --git a/doc/nftables.xml b/doc/nftables.xml deleted file mode 100644 index 702891c2..00000000 --- a/doc/nftables.xml +++ /dev/null @@ -1,2168 +0,0 @@ -<?xml version="1.0" encoding="UTF-8" ?> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" -"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> -<!-- -vi:ts=4 sw=4 ---> - -<refentry xmlns:xi="http://www.w3.org/2001/XInclude"> - <refentryinfo> - <author> - <firstname>Patrick</firstname> - <surname>McHardy</surname> - <email>kaber@trash.net</email> - </author> - <copyright> - <year>2008-2014</year> - <holder>Patrick McHardy</holder> - </copyright> - </refentryinfo> - - <refmeta> - <refentrytitle>nft</refentrytitle> - <manvolnum>8</manvolnum> - </refmeta> - - <refnamediv> - <refname>nft</refname> - <refpurpose> - Administration tool for packet filtering and classification - </refpurpose> - </refnamediv> - - <refsynopsisdiv> - <cmdsynopsis> - <command>nft</command> - <arg choice="opt"> - <option>-n/--numeric</option> - </arg> - <arg choice="opt"> - <option>-I/--includepath</option> - <replaceable>directory</replaceable> - </arg> - <group> - <arg choice="opt"> - <option>-f/--file</option> - <replaceable>filename</replaceable> - </arg> - <arg choice="opt"> - <option>-i/--interactive</option> - </arg> - <arg choice="opt" rep="repeat"> - <replaceable>cmd</replaceable> - </arg> - </group> - </cmdsynopsis> - <cmdsynopsis> - <command>nft</command> - <arg choice="opt"> - <option>-h/--help</option> - </arg> - <arg choice="opt"> - <option>-v/--version</option> - </arg> - </cmdsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - <para> - nft is used to set up, maintain and inspect packet - filtering and classification rules in the Linux kernel. - </para> - </refsect1> - - <refsect1> - <title>Options</title> - <para> - For a full summary of options, run <command>nft --help</command>. - </para> - - <variablelist> - <varlistentry> - <term><option>-h/--help</option></term> - <listitem> - <para> - Show help message and all options. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>-v/--version</option></term> - <listitem> - <para> - Show version. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>-n/--numeric</option></term> - <listitem> - <para> - Numeric output: Addresses and other information - that might need network traffic to resolve to symbolic names - are shown numerically. When used twice, internet services - and UIDs/GIDs are also shown numerically. When used thrice, - protocol numbers are also shown numerically. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>-a/--handle</option></term> - <listitem> - <para> - Show rule handles in output. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>-I/--includepath <replaceable>directory</replaceable></option></term> - <listitem> - <para> - Add the directory <replaceable>directory</replaceable> to the list of directories to by searched for included files. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>-f/--file <replaceable>filename</replaceable></option></term> - <listitem> - <para> - Read input from <replaceable>filename</replaceable>. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>-i/--interactive</option></term> - <listitem> - <para> - Read input from an interactive readline CLI. - </para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Input file format</title> - <refsect2> - <title>Lexical conventions</title> - <para> - Input is parsed line-wise. When the last character of a line just before - the newline character is a non-quoted backslash (<literal>\</literal>), - the next line is treated as a continuation. Multiple commands on the - same line can be separated using a semicolon (<literal>;</literal>). - </para> - <para> - A hash sign (<literal>#</literal>) begins a comment. All following characters - on the same line are ignored. - </para> - <para> - Identifiers begin with an alphabetic character (<literal>a-z,A-Z</literal>), - followed zero or more alphanumeric characters (<literal>a-z,A-Z,0-9</literal>) - and the characters slash (<literal>/</literal>), backslash (<literal>\</literal>), - underscore (<literal>_</literal>) and dot (<literal>.</literal>). Identifiers - using different characters or clashing with a keyword need to be enclosed in - double quotes (<literal>"</literal>). - </para> - <para> - </para> - </refsect2> - <refsect2> - <title>Include files</title> - <para> - <cmdsynopsis> - <command>include</command> "<replaceable>filename</replaceable>" - </cmdsynopsis> - </para> - <para> - Other files can be included by using the <command>include</command> statement. - The directories to be searched for include files can be specified using - the <option>-I/--includepath</option> option. - </para> - </refsect2> - <refsect2> - <title>Symbolic variables</title> - <para> - <cmdsynopsis> - <command>define</command> <varname><replaceable>variable</replaceable></varname> = <replaceable>expr</replaceable> - </cmdsynopsis> - <cmdsynopsis> - <command>$<varname><replaceable>variable</replaceable></varname></command> - </cmdsynopsis> - </para> - <para> - Symbolic variables can be defined using the <command>define</command> statement. - Variable references are expressions and can be used initialize other variables. - The scope of a definition is the current block and all blocks contained within. - - <example> - <title>Using symbolic variables</title> - <programlisting> -define int_if1 = eth0 -define int_if2 = eth1 -define int_ifs = { $int_if1, $int_if2 } - -filter input iif $int_ifs accept - </programlisting> - </example> - </para> - </refsect2> - </refsect1> - - <refsect1> - <title>Address families</title> - <para> - Address families determine the type of packets which are processed. For each address - family the kernel contains so called hooks at specific stages of the packet processing - paths, which invoke nftables if rules for these hooks exist. - </para> - <para> - <variablelist> - <varlistentry> - <term><option>ip</option></term> - <listitem> - <para> - IPv4 address family. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>ip6</option></term> - <listitem> - <para> - IPv6 address family. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>inet</option></term> - <listitem> - <para> - Internet (IPv4/IPv6) address family. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>arp</option></term> - <listitem> - <para> - ARP address family, handling packets vi - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>bridge</option></term> - <listitem> - <para> - Bridge address family, handling packets which traverse a bridge device. - </para> - </listitem> - </varlistentry> - </variablelist> - </para> - <para> - All nftables objects exist in address family specific namespaces, therefore - all identifiers include an address family. If an identifier is specified without - an address family, the <literal>ip</literal> family is used by default. - </para> - - <refsect2> - <title>IPv4/IPv6/Inet address families</title> - <para> - The IPv4/IPv6/Inet address families handle IPv4, IPv6 or both types of packets. They - contain five hooks at different packet processing stages in the network stack. - </para> - <para> - <table frame="all"> - <title>IPv4/IPv6/Inet address family hooks</title> - <tgroup cols='2' align='left' colsep='1' rowsep='1'> - <colspec colname='c1' colwidth="1*"/> - <colspec colname='c2' colwidth="5*"/> - <thead> - <row> - <entry>Hook</entry> - <entry>Description</entry> - </row> - </thead> - <tbody> - <row> - <entry>prerouting</entry> - <entry> - All packets entering the system are processed by the prerouting hook. It is invoked - before the routing process and is used for early filtering or changing packet - attributes that affect routing. - </entry> - </row> - <row> - <entry>input</entry> - <entry> - Packets delivered to the local system are processed by the input hook. - </entry> - </row> - <row> - <entry>forward</entry> - <entry> - Packets forwarded to a different host are processed by the forward hook. - </entry> - </row> - <row> - <entry>output</entry> - <entry> - Packets sent by local processes are processed by the output hook. - </entry> - </row> - <row> - <entry>postrouting</entry> - <entry> - All packets leaving the system are processed by the postrouting hook. - </entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - <refsect2> - <title>ARP address family</title> - <para> - The ARP address family handles ARP packets received and sent by the system. It is commonly used - to mangle ARP packets for clustering. - </para> - <para> - <table frame="all"> - <title>ARP address family hooks</title> - <tgroup cols='2' align='left' colsep='1' rowsep='1' pgwide="1"> - <colspec colname='c1' colwidth="1*"/> - <colspec colname='c2' colwidth="5*"/> - <thead> - <row> - <entry>Hook</entry> - <entry>Description</entry> - </row> - </thead> - <tbody> - <row> - <entry>input</entry> - <entry> - Packets delivered to the local system are processed by the input hook. - </entry> - </row> - <row> - <entry>output</entry> - <entry> - Packets send by the local system are processed by the output hook. - </entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - <refsect2> - <title>Bridge address family</title> - <para> - The bridge address family handles ethernet packets traversing bridge devices. - </para> - </refsect2> - </refsect1> - - <refsect1> - <title>Tables</title> - <para> - <cmdsynopsis> - <group choice="req"> - <arg>add</arg> - <arg>delete</arg> - <arg>list</arg> - <arg>flush</arg> - </group> - <command>table</command> - <arg choice="opt"><replaceable>family</replaceable></arg> - <arg choice="req"><replaceable>table</replaceable></arg> - </cmdsynopsis> - </para> - - <para> - Tables are containers for chains and sets. They are identified by their address family - and their name. The address family must be one of - - <simplelist type="inline"> - <member><literal>ip</literal></member> - <member><literal>ip6</literal></member> - <member><literal>inet</literal></member> - <member><literal>arp</literal></member> - <member><literal>bridge</literal></member> - </simplelist>. - - The <literal>inet</literal> address family is a dummy family which is used to create - hybrid IPv4/IPv6 tables. - - When no address family is specified, <literal>ip</literal> is used by default. - </para> - - <variablelist> - <varlistentry> - <term><option>add</option></term> - <listitem> - <para> - Add a new table for the given family with the given name. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>delete</option></term> - <listitem> - <para> - Delete the specified table. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>list</option></term> - <listitem> - <para> - List all chains and rules of the specified table. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>flush</option></term> - <listitem> - <para> - Flush all chains and rules of the specified table. - </para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Chains</title> - <para> - <cmdsynopsis> - <arg choice="req">add</arg> - <command>chain</command> - <arg choice="opt"><replaceable>family</replaceable></arg> - <arg choice="req"><replaceable>table</replaceable></arg> - <arg choice="req"><replaceable>chain</replaceable></arg> - <arg choice="req"><replaceable>hook</replaceable></arg> - <arg choice="req"><replaceable>priority</replaceable></arg> - </cmdsynopsis> - <cmdsynopsis> - <group choice="req"> - <arg>add</arg> - <arg>create</arg> - <arg>delete</arg> - <arg>list</arg> - <arg>flush</arg> - </group> - <command>chain</command> - <arg choice="opt"><replaceable>family</replaceable></arg> - <arg choice="req"><replaceable>table</replaceable></arg> - <arg choice="req"><replaceable>chain</replaceable></arg> - </cmdsynopsis> - <cmdsynopsis> - <arg choice="req">rename</arg> - <command>chain</command> - <arg choice="opt"><replaceable>family</replaceable></arg> - <arg choice="req"><replaceable>table</replaceable></arg> - <arg choice="req"><replaceable>chain</replaceable></arg> - <arg choice="req"><replaceable>newname</replaceable></arg> - </cmdsynopsis> - </para> - - <para> - Chains are containers for rules. They exist in two kinds, - base chains and regular chains. A base chain is an entry point for - packets from the networking stack, a regular chain may be used - as jump target and is used for better rule organization. - </para> - - <variablelist> - <varlistentry> - <term><option>add</option></term> - <listitem> - <para> - Add a new chain in the specified table. When a hook and priority - value are specified, the chain is created as a base chain and hooked - up to the networking stack. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>create</option></term> - <listitem> - <para> - Simlar to the <command>add</command> command, but returns an error if the - chain already exists. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>delete</option></term> - <listitem> - <para> - Delete the specified chain. The chain must not contain any rules or be - used as jump target. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>flush</option></term> - <listitem> - <para> - Rename the specified chain. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>list</option></term> - <listitem> - <para> - List all rules of the specified chain. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>flush</option></term> - <listitem> - <para> - Flush all rules of the specified chain. - </para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Rules</title> - <para> - <cmdsynopsis> - <group> - <arg choice="opt">add</arg> - <arg choice="req">insert</arg> - </group> - <command>rule</command> - <arg choice="opt"><replaceable>family</replaceable></arg> - <arg choice="req"><replaceable>table</replaceable></arg> - <arg choice="req"><replaceable>chain</replaceable></arg> - <arg choice="opt">position <replaceable>position</replaceable></arg> - <arg choice="req" rep="repeat"><replaceable>statement</replaceable></arg> - </cmdsynopsis> - <cmdsynopsis> - <arg choice="req">delete</arg> - <command>rule</command> - <arg choice="opt"><replaceable>family</replaceable></arg> - <arg choice="req"><replaceable>table</replaceable></arg> - <arg choice="req"><replaceable>chain</replaceable></arg> - <arg choice="req">handle <replaceable>handle</replaceable></arg> - </cmdsynopsis> - </para> - <para> - Rules are constructed from two kinds of components according to a set - of grammatical rules: expressions and statements. - </para> - - <variablelist> - <varlistentry> - <term><option>add</option></term> - <listitem> - <para> - Add a new rule described by the list of statements. The rule is appended to the - given chain unless a position is specified, in which case the rule is appended to - the rule given by the position. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>insert</option></term> - <listitem> - <para> - Similar to the <command>add</command> command, but the rule is prepended to the - beginning of the chain or before the rule at the given position. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>delete</option></term> - <listitem> - <para> - Delete the specified rule. - </para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Expressions</title> - <para> - Expressions represent values, either constants like network addresses, port numbers etc. or data - gathered from the packet during ruleset evaluation. Expressions can be combined using binary, - logical, relational and other types of expressions to form complex or relational (match) expressions. - They are also used as arguments to certain types of operations, like NAT, packet marking etc. - </para> - <para> - Each expression has a data type, which determines the size, parsing and representation of - symbolic values and type compatibility with other expressions. - </para> - - <refsect2> - <title>describe command</title> - <para> - <cmdsynopsis> - <command>describe</command> - <arg choice="req"><replaceable>expression</replaceable></arg> - </cmdsynopsis> - </para> - <para> - The <command>describe</command> command shows information about the type of an expression and - its data type. - </para> - <example> - <title>The <command>describe</command> command</title> - <programlisting> -$ nft describe tcp flags -payload expression, datatype tcp_flag (TCP flag) (basetype bitmask, integer), 8 bits - -pre-defined symbolic constants: -fin 0x01 -syn 0x02 -rst 0x04 -psh 0x08 -ack 0x10 -urg 0x20 -ecn 0x40 -cwr 0x80 - </programlisting> - </example> - </refsect2> - </refsect1> - - <refsect1> - <title>Data types</title> - <para> - Data types determine the size, parsing and representation of symbolic values and type compatibility - of expressions. A number of global data types exist, in addition some expression types define further - data types specific to the expression type. Most data types have a fixed size, some however may have - a dynamic size, f.i. the string type. - </para> - <para> - Types may be derived from lower order types, f.i. the IPv4 address type is derived from the integer - type, meaning an IPv4 address can also be specified as an integer value. - </para> - <para> - In certain contexts (set and map definitions) it is necessary to explicitly specify a data type. - Each type has a name which is used for this. - </para> - - <refsect2> - <title>Integer type</title> - <para> - <table frame="all"> - <tgroup cols='4' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <colspec colname='c4'/> - <thead> - <row> - <entry>Name</entry> - <entry>Keyword</entry> - <entry>Size</entry> - <entry>Base type</entry> - </row> - </thead> - <tbody> - <row> - <entry>Integer</entry> - <entry>integer</entry> - <entry>variable</entry> - <entry>-</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - The integer type is used for numeric values. It may be specified as decimal, hexadecimal - or octal number. The integer type doesn't have a fixed size, its size is determined by the - expression for which it is used. - </para> - </refsect2> - - <refsect2> - <title>Bitmask type</title> - <para> - <table frame="all"> - <tgroup cols='4' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <colspec colname='c4'/> - <thead> - <row> - <entry>Name</entry> - <entry>Keyword</entry> - <entry>Size</entry> - <entry>Base type</entry> - </row> - </thead> - <tbody> - <row> - <entry>Bitmask</entry> - <entry>bitmask</entry> - <entry>variable</entry> - <entry>integer</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - The bitmask type (<command>bitmask</command>) is used for bitmasks. - </para> - </refsect2> - - <refsect2> - <title>String type</title> - <para> - <table frame="all"> - <tgroup cols='4' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <colspec colname='c4'/> - <thead> - <row> - <entry>Name</entry> - <entry>Keyword</entry> - <entry>Size</entry> - <entry>Base type</entry> - </row> - </thead> - <tbody> - <row> - <entry>String</entry> - <entry>string</entry> - <entry>variable</entry> - <entry>-</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - The string type is used to for character strings. A string begins with an alphabetic character - (a-zA-Z) followed by zero or more alphanumeric characters or the characters <literal>/</literal>, - <literal>-</literal>, <literal>_</literal> and <literal>.</literal>. In addition anything enclosed - in double quotes (<literal>"</literal>) is recognized as a string. - </para> - <example> - <title>String specification</title> - <programlisting> -# Interface name -filter input iifname eth0 - -# Weird interface name -filter input iifname "(eth0)" - </programlisting> - </example> - </refsect2> - - <refsect2> - <title>Link layer address type</title> - <para> - <table frame="all"> - <tgroup cols='4' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <colspec colname='c4'/> - <thead> - <row> - <entry>Name</entry> - <entry>Keyword</entry> - <entry>Size</entry> - <entry>Base type</entry> - </row> - </thead> - <tbody> - <row> - <entry>Link layer address</entry> - <entry>lladdr</entry> - <entry>variable</entry> - <entry>integer</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - The link layer address type is used for link layer addresses. Link layer addresses are specified - as a variable amount of groups of two hexadecimal digits separated using colons (<literal>:</literal>). - </para> - <example> - <title>Link layer address specification</title> - <programlisting> -# Ethernet destination MAC address -filter input ether daddr 20:c9:d0:43:12:d9 - </programlisting> - </example> - </refsect2> - - <refsect2> - <title>IPv4 address type</title> - <para> - <table frame="all"> - <tgroup cols='4' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <colspec colname='c4'/> - <thead> - <row> - <entry>Name</entry> - <entry>Keyword</entry> - <entry>Size</entry> - <entry>Base type</entry> - </row> - </thead> - <tbody> - <row> - <entry>IPv4 address</entry> - <entry>ipv4_addr</entry> - <entry>32 bit</entry> - <entry>integer</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - The IPv4 address type is used for IPv4 addresses. Addresses are specified in either dotted decimal, - dotted hexadecimal, dotted octal, decimal, hexadecimal, octal notation or as a host name. A host name - will be resolved using the standard system resolver. - </para> - <example> - <title>IPv4 address specification</title> - <programlisting> -# dotted decimal notation -filter output ip daddr 127.0.0.1 - -# host name -filter output ip daddr localhost - </programlisting> - </example> - </refsect2> - - <refsect2> - <title>IPv6 address type</title> - <para> - <table frame="all"> - <tgroup cols='4' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <colspec colname='c4'/> - <thead> - <row> - <entry>Name</entry> - <entry>Keyword</entry> - <entry>Size</entry> - <entry>Base type</entry> - </row> - </thead> - <tbody> - <row> - <entry>IPv6 address</entry> - <entry>ipv6_addr</entry> - <entry>128 bit</entry> - <entry>integer</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - The IPv6 address type is used for IPv6 addresses. FIXME - </para> - <example> - <title>IPv6 address specification</title> - <programlisting> -# abbreviated loopback address -filter output ip6 daddr ::1 - </programlisting> - </example> - </refsect2> - </refsect1> - - <refsect1> - <title>Primary expressions</title> - <para> - The lowest order expression is a primary expression, representing either a constant or a single - datum from a packet's payload, meta data or a stateful module. - </para> - <refsect2> - <title>Meta expressions</title> - <para> - <cmdsynopsis> - <command>meta</command> - <group choice="req"> - <arg>length</arg> - <arg>nfproto</arg> - <arg>l4proto</arg> - <arg>protocol</arg> - <arg>priority</arg> - </group> - </cmdsynopsis> - <cmdsynopsis> - <arg choice="opt">meta</arg> - <group choice="req"> - <arg>mark</arg> - <arg>iif</arg> - <arg>iifname</arg> - <arg>iiftype</arg> - <arg>oif</arg> - <arg>oifname</arg> - <arg>oiftype</arg> - <arg>skuid</arg> - <arg>skgid</arg> - <arg>nftrace</arg> - <arg>rtclassid</arg> - </group> - </cmdsynopsis> - </para> - <para> - A meta expression refers to meta data associated with a packet. - </para> - <para> - There are two types of meta expressions: unqualified and qualified meta expressions. - Qualified meta expressions require the <command>meta</command> keyword before the - meta key, unqualified meta expressions can be specified by using the meta key directly - or as qualified meta expressions. - </para> - <para> - <table frame="all"> - <title>Meta expression types</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>length</entry> - <entry>Length of the packet in bytes</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>protocol</entry> - <entry>Ethertype protocol value</entry> - <entry>ether_type</entry> - </row> - <row> - <entry>priority</entry> - <entry>TC packet priority</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>mark</entry> - <entry>Packet mark</entry> - <entry>packetmark</entry> - </row> - <row> - <entry>iif</entry> - <entry>Input interface index</entry> - <entry>iface_index</entry> - </row> - <row> - <entry>iifname</entry> - <entry>Input interface name</entry> - <entry>string</entry> - </row> - <row> - <entry>iiftype</entry> - <entry>Input interface type</entry> - <entry>iface_type</entry> - </row> - <row> - <entry>oif</entry> - <entry>Output interface index</entry> - <entry>iface_index</entry> - </row> - <row> - <entry>oifname</entry> - <entry>Output interface name</entry> - <entry>string</entry> - </row> - <row> - <entry>oiftype</entry> - <entry>Output interface hardware type</entry> - <entry>iface_type</entry> - </row> - <row> - <entry>skuid</entry> - <entry>UID associated with originating socket</entry> - <entry>uid</entry> - </row> - <row> - <entry>skgid</entry> - <entry>GID associated with originating socket</entry> - <entry>gid</entry> - </row> - <row> - <entry>rtclassid</entry> - <entry>Routing realm</entry> - <entry>realm</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - <table frame="all"> - <title>Meta expression specific types</title> - <tgroup cols='2' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <thead> - <row> - <entry>Type</entry> - <entry>Description</entry> - </row> - </thead> - <tbody> - <row> - <entry>iface_index</entry> - <entry> - Interface index (32 bit number). Can be specified numerically - or as name of an existing interface. - </entry> - </row> - <row> - <entry>ifname</entry> - <entry> - Interface name (16 byte string). Does not have to exist. - </entry> - </row> - <row> - <entry>iface_type</entry> - <entry> - Interface type (16 bit number). - </entry> - </row> - <row> - <entry>uid</entry> - <entry> - User ID (32 bit number). Can be specified numerically or as - user name. - </entry> - </row> - <row> - <entry>gid</entry> - <entry> - Group ID (32 bit number). Can be specified numerically or as - group name. - </entry> - </row> - <row> - <entry>realm</entry> - <entry> - Routing Realm (32 bit number). Can be specified numerically - or as symbolic name defined in /etc/iproute2/rt_realms. - </entry> - </row> - </tbody> - </tgroup> - </table> - </para> - <para> - <example> - <title>Using meta expressions</title> - <programlisting> -# qualified meta expression -filter output meta oif eth0 - -# unqualified meta expression -filter output oif eth0 - </programlisting> - </example> - </para> - </refsect2> - </refsect1> - - <refsect1> - <title>Payload expressions</title> - <para> - Payload expressions refer to data from the packet's payload. - </para> - - <refsect2> - <title>Ethernet header expression</title> - <para> - <cmdsynopsis> - <command>ether</command> - <arg opt="req"><replaceable>ethernet header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>Ethernet header expression types</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>daddr</entry> - <entry>Destination MAC address</entry> - <entry>ether_addr</entry> - </row> - <row> - <entry>saddr</entry> - <entry>Source MAC address</entry> - <entry>ether_addr</entry> - </row> - <row> - <entry>type</entry> - <entry>EtherType</entry> - <entry>ether_type</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>VLAN header expression</title> - <para> - <cmdsynopsis> - <command>vlan</command> - <arg opt="req"><replaceable>VLAN header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>VLAN header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c2'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>id</entry> - <entry>VLAN ID (VID)</entry> - <entry>integer (12 bit)</entry> - </row> - <row> - <entry>cfi</entry> - <entry>Canonical Format Indicator</entry> - <entry>flag</entry> - </row> - <row> - <entry>pcp</entry> - <entry>Priority code point</entry> - <entry>integer (3 bit)</entry> - </row> - <row> - <entry>type</entry> - <entry>EtherType</entry> - <entry>ethertype</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>ARP header expression</title> - <para> - <cmdsynopsis> - <command>arp</command> - <arg opt="req"><replaceable>ARP header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>ARP header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>htype</entry> - <entry>ARP hardware type</entry> - <entry>FIXME</entry> - </row> - <row> - <entry>ptype</entry> - <entry>EtherType</entry> - <entry>ethertype</entry> - </row> - <row> - <entry>hlen</entry> - <entry>Hardware address len</entry> - <entry>integer (8 bit)</entry> - </row> - <row> - <entry>plen</entry> - <entry>Protocol address len</entry> - <entry>integer (8 bit)</entry> - </row> - <row> - <entry>op</entry> - <entry>Operation</entry> - <entry>FIXME</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>IPv4 header expression</title> - <para> - <cmdsynopsis> - <command>ip</command> - <arg opt="req"><replaceable>IPv4 header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>IPv4 header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>version</entry> - <entry>IP header version (4)</entry> - <entry>integer (4 bit)</entry> - </row> - <row> - <entry>hdrlength</entry> - <entry>IP header length including options</entry> - <entry>integer (4 bit) FIXME scaling</entry> - </row> - <row> - <entry>tos</entry> - <entry>Type Of Service</entry> - <entry>FIXME</entry> - </row> - <row> - <entry>length</entry> - <entry>Total packet length</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>id</entry> - <entry>IP ID</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>frag-off</entry> - <entry>Fragment offset</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>ttl</entry> - <entry>Time to live</entry> - <entry>integer (8 bit)</entry> - </row> - <row> - <entry>protocol</entry> - <entry>Upper layer protocol</entry> - <entry>inet_proto</entry> - </row> - <row> - <entry>checksum</entry> - <entry>IP header checksum</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>saddr</entry> - <entry>Source address</entry> - <entry>ipv4_addr</entry> - </row> - <row> - <entry>daddr</entry> - <entry>Destination address</entry> - <entry>ipv4_addr</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>IPv6 header expression</title> - <para> - <cmdsynopsis> - <command>ip6</command> - <arg opt="req"><replaceable>IPv6 header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>IPv6 header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>version</entry> - <entry>IP header version (6)</entry> - <entry>integer (4 bit)</entry> - </row> - <row> - <entry>priority</entry> - <entry></entry> - <entry></entry> - </row> - <row> - <entry>flowlabel</entry> - <entry>Flow label</entry> - <entry></entry> - </row> - <row> - <entry>length</entry> - <entry>Payload length</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>nexthdr</entry> - <entry>Nexthdr protocol</entry> - <entry>inet_proto</entry> - </row> - <row> - <entry>hoplimit</entry> - <entry>Hop limit</entry> - <entry>integer (8 bit)</entry> - </row> - <row> - <entry>saddr</entry> - <entry>Source address</entry> - <entry>ipv6_addr</entry> - </row> - <row> - <entry>daddr</entry> - <entry>Destination address</entry> - <entry>ipv6_addr</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>TCP header expression</title> - <para> - <cmdsynopsis> - <command>tcp</command> - <arg opt="req"><replaceable>TCP header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>TCP header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>sport</entry> - <entry>Source port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>dport</entry> - <entry>Destination port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>sequence</entry> - <entry>Sequence number</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>ackseq</entry> - <entry>Acknowledgement number</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>doff</entry> - <entry>Data offset</entry> - <entry>integer (4 bit) FIXME scaling</entry> - </row> - <row> - <entry>reserved</entry> - <entry>Reserved area</entry> - <entry>FIXME</entry> - </row> - <row> - <entry>flags</entry> - <entry>TCP flags</entry> - <entry>tcp_flags</entry> - </row> - <row> - <entry>window</entry> - <entry>Window</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>checksum</entry> - <entry>Checksum</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>urgptr</entry> - <entry>Urgent pointer</entry> - <entry>integer (16 bit)</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>UDP header expression</title> - <para> - <cmdsynopsis> - <command>udp</command> - <arg opt="req"><replaceable>UDP header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>UDP header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>sport</entry> - <entry>Source port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>dport</entry> - <entry>Destination port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>length</entry> - <entry>Total packet length</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>checksum</entry> - <entry>Checksum</entry> - <entry>integer (16 bit)</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>UDP-Lite header expression</title> - <para> - <cmdsynopsis> - <command>udplite</command> - <arg opt="req"><replaceable>UDP-Lite header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>UDP-Lite header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>sport</entry> - <entry>Source port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>dport</entry> - <entry>Destination port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>cscov</entry> - <entry>Checksum coverage</entry> - <entry>integer (16 bit)</entry> - </row> - <row> - <entry>checksum</entry> - <entry>Checksum</entry> - <entry>integer (16 bit)</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - - <refsect2> - <title>SCTP header expression</title> - <para> - <cmdsynopsis> - <command>sctp</command> - <arg opt="req"><replaceable>SCTP header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>SCTP header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>sport</entry> - <entry>Source port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>dport</entry> - <entry>Destination port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>vtag</entry> - <entry>Verfication Tag</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>checksum</entry> - <entry>Checksum</entry> - <entry>integer (32 bit)</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>DCCP header expression</title> - <para> - <cmdsynopsis> - <command>dccp</command> - <arg opt="req"><replaceable>DCCP header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>DCCP header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>sport</entry> - <entry>Source port</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>dport</entry> - <entry>Destination port</entry> - <entry>inet_service</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>Authentication header expression</title> - <para> - <cmdsynopsis> - <command>ah</command> - <arg opt="req"><replaceable>AH header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>AH header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>nexthdr</entry> - <entry>Next header protocol</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>hdrlength</entry> - <entry>AH Header length</entry> - <entry>integer (8 bit)</entry> - </row> - <row> - <entry>reserved</entry> - <entry>Reserved area</entry> - <entry>FIXME</entry> - </row> - <row> - <entry>spi</entry> - <entry>Security Parameter Index</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>sequence</entry> - <entry>Sequence number</entry> - <entry>integer (32 bit)</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title> Encrypted security payload header expression</title> - <para> - <cmdsynopsis> - <command>esp</command> - <arg opt="req"><replaceable>ESP header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>ESP header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>spi</entry> - <entry>Security Parameter Index</entry> - <entry>integer (32 bit)</entry> - </row> - <row> - <entry>sequence</entry> - <entry>Sequence number</entry> - <entry>integer (32 bit)</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - - <refsect2> - <title>IPcomp header expression</title> - <para> - <cmdsynopsis> - <command>ipcomp</command> - <arg opt="req"><replaceable>IPComp header field</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>IPComp header expression</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>nexthdr</entry> - <entry>Next header protocol</entry> - <entry>inet_service</entry> - </row> - <row> - <entry>flags</entry> - <entry>Flags</entry> - <entry>FIXME</entry> - </row> - <row> - <entry>cfi</entry> - <entry>Compression Parameter Index</entry> - <entry>FIXME</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - </refsect1> - - <refsect1> - <title>bla</title> - <refsect2> - <title>IPv6 extension header expressions</title> - <para> - IPv6 extension header expressions refer to data from an IPv6 packet's extension headers. - </para> - </refsect2> - - <refsect2> - <title>Conntrack expressions</title> - <para> - Conntrack expressions refer to meta data of the connection tracking entry associated with a packet. - </para> - <para> - <cmdsynopsis> - <command>ct</command> - <group choice="req"> - <arg>state</arg> - <arg>direction</arg> - <arg>status</arg> - <arg>mark</arg> - <arg>expiration</arg> - <arg>helper</arg> - <arg>l3proto</arg> - <arg>saddr</arg> - <arg>daddr</arg> - <arg>protocol</arg> - <arg>proto-src</arg> - <arg>proto-dst</arg> - </group> - </cmdsynopsis> - </para> - <para> - <table frame="all"> - <title>Conntrack expressions</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname='c1'/> - <colspec colname='c2'/> - <colspec colname='c3'/> - <thead> - <row> - <entry>Keyword</entry> - <entry>Description</entry> - <entry>Type</entry> - </row> - </thead> - <tbody> - <row> - <entry>state</entry> - <entry>State of the connection</entry> - <entry>ct_state</entry> - </row> - <row> - <entry>direction</entry> - <entry>Direction of the packet relative to the connection</entry> - <entry>ct_dir</entry> - </row> - <row> - <entry>status</entry> - <entry>Status of the connection</entry> - <entry>ct_status</entry> - </row> - <row> - <entry>mark</entry> - <entry>Connection mark</entry> - <entry>packetmark</entry> - </row> - <row> - <entry>expiration</entry> - <entry>Connection expiration time</entry> - <entry>time</entry> - </row> - <row> - <entry>helper</entry> - <entry>Helper associated with the connection</entry> - <entry>string</entry> - </row> - <row> - <entry>l3proto</entry> - <entry>Layer 3 protocol of the connection</entry> - <entry>nf_proto FIXME</entry> - </row> - <row> - <entry>saddr</entry> - <entry>Source address of the connection for the given direction</entry> - <entry>ipv4_addr/ipv6_addr</entry> - </row> - <row> - <entry>daddr</entry> - <entry>Destination address of the connection for the given direction</entry> - <entry>ipv4_addr/ipv6_addr</entry> - </row> - <row> - <entry>protocol</entry> - <entry>Layer 4 protocol of the connection for the given direction</entry> - <entry>inet_proto</entry> - </row> - <row> - <entry>proto-src</entry> - <entry>Layer 4 protocol source for the given direction</entry> - <entry>FIXME</entry> - </row> - <row> - <entry>proto-dst</entry> - <entry>Layer 4 protocol destination for the given direction</entry> - <entry>FIXME</entry> - </row> - </tbody> - </tgroup> - </table> - </para> - </refsect2> - </refsect1> - - <refsect1> - <title>Statements</title> - <para> - Statements represent actions to be performed. They can alter control flow (return, jump - to a different chain, accept or drop the packet) or can perform actions, such as logging, - rejecting a packet, etc. - </para> - <para> - Statements exist in two kinds. Terminal statements unconditionally terminate evaluation - of the current rule, non-terminal statements either only conditionally or never terminate - evaluation of the current rule, in other words, they are passive from the ruleset evaluation - perspective. There can be an arbitrary amount of non-terminal statements in a rule, but - only a single terminal statement as the final statement. - </para> - - <refsect2> - <title>Verdict statement</title> - <para> - The verdict statement alters control flow in the ruleset and issues - policy decisions for packets. - </para> - <para> - <cmdsynopsis> - <group choice="req"> - <arg>accept</arg> - <arg>drop</arg> - <arg>queue</arg> - <arg>continue</arg> - <arg>return</arg> - </group> - </cmdsynopsis> - <cmdsynopsis> - <group choice="req"> - <arg>jump</arg> - <arg>goto</arg> - </group> - <arg choice="req"><replaceable>chain</replaceable></arg> - </cmdsynopsis> - </para> - <para> - <variablelist> - <varlistentry> - <term><option>accept</option></term> - <listitem> - <para> - Terminate ruleset evaluation and accept the packet. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>drop</option></term> - <listitem> - <para> - Terminate ruleset evaluation and drop the packet. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>queue</option></term> - <listitem> - <para> - Terminate ruleset evaluation and queue the packet to userspace. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>continue</option></term> - <listitem> - <para> - Continue ruleset evaluation with the next rule. FIXME - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>return</option></term> - <listitem> - <para> - Return from the current chain and continue evaluation at the - next rule in the last chain. If issued in a base chain, it is - equivalent to <command>accept</command>. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>jump <replaceable>chain</replaceable></option></term> - <listitem> - <para> - Continue evaluation at the first rule in <replaceable>chain</replaceable>. - The current position in the ruleset is pushed to a call stack and evaluation - will continue there when the new chain is entirely evaluated of a - <command>return</command> verdict is issued. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term><option>goto <replaceable>chain</replaceable></option></term> - <listitem> - <para> - Similar to <command>jump</command>, but the current position is not pushed - to the call stack, meaning that after the new chain evaluation will continue - at the last chain instead of the one containing the goto statement. - </para> - </listitem> - </varlistentry> - </variablelist> - </para> - <para> - <example> - <title>Verdict statements</title> - <programlisting> -# process packets from eth0 and the internal network in from_lan -# chain, drop all packets from eth0 with different source addresses. - -filter input iif eth0 ip saddr 192.168.0.0/24 jump from_lan -filter input iif eth0 drop - </programlisting> - </example> - </para> - </refsect2> - <refsect2> - <title>Log statement</title> - <para> - </para> - </refsect2> - <refsect2> - <title>Reject statement</title> - <para> - </para> - </refsect2> - <refsect2> - <title>Counter statement</title> - <para> - </para> - </refsect2> - <refsect2> - <title>Meta statement</title> - <para> - </para> - </refsect2> - <refsect2> - <title>Limit statement</title> - <para> - </para> - </refsect2> - <refsect2> - <title>NAT statement</title> - <para> - </para> - </refsect2> - <refsect2> - <title>Queue statement</title> - <para> - </para> - </refsect2> - </refsect1> - - <refsect1> - <title>Error reporting</title> - <para> - When an error is detected, nft shows the line(s) containing the error, the position - of the erroneous parts in the input stream and marks up the erroneous parts using - carrets (<literal>^</literal>). If the error results from the combination of two - expressions or statements, the part imposing the constraints which are violated is - marked using tildes (<literal>~</literal>). - </para> - <para> - For errors returned by the kernel, nft can't detect which parts of the input caused - the error and the entire command is marked. - </para> - <example> - <title>Error caused by single incorrect expression</title> - <programlisting> -<cmdline>:1:19-22: Error: Interface does not exist -filter output oif eth0 -^^^ - </programlisting> - </example> - <example> - <title>Error caused by invalid combination of two expressions</title> - <programlisting> -<cmdline>:1:28-36: Error: Right hand side of relational expression (==) must be constant -filter output tcp dport == tcp dport -~~ ^^^^^^^^^ - </programlisting> - </example> - - <example> - <title>Error returned by the kernel</title> - <programlisting> -<cmdline>:0:0-23: Error: Could not process rule: Operation not permitted -filter output oif wlan0 -^^^^^^^^^^^^^^^^^^^^^^^ - </programlisting> - </example> - </refsect1> - - <refsect1> - <title>Exit status</title> - <para> - On success, nft exits with a status of 0. Unspecified - errors cause it to exit with a status of 1, memory allocation - errors with a status of 2. - </para> - </refsect1> - - <refsect1> - <title>See Also</title> - <para> - <simplelist type="inline"> - <member>iptables(8)</member> - <member>ip6tables(8)</member> - <member>arptables(8)</member> - <member>ebtables(8)</member> - <member>ip(8)</member> - <member>tc(8)</member> - </simplelist> - </para> - </refsect1> - - <refsect1> - <title>Authors</title> - <para> - nftables was written by Patrick McHardy. - </para> - </refsect1> - - <refsect1> - <title>Copyright</title> - <para> - Copyright © 2008-2014 Patrick McHardy <email>kaber@trash.net</email> - </para> - <para> - nftables is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License version 2 as - published by the Free Software Foundation. - </para> - <para> - This documentation is licenced under the terms of the Creative - Commons Attribution-ShareAlike 4.0 license, - <ulink url="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA 4.0</ulink>. - </para> - </refsect1> -</refentry> |