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Diffstat (limited to 'docs/configuration/firewall/index.rst')
| -rw-r--r-- | docs/configuration/firewall/index.rst | 112 |
1 files changed, 19 insertions, 93 deletions
diff --git a/docs/configuration/firewall/index.rst b/docs/configuration/firewall/index.rst index a13b4328..c5be158f 100644 --- a/docs/configuration/firewall/index.rst +++ b/docs/configuration/firewall/index.rst @@ -17,7 +17,7 @@ The firewall supports the creation of groups for ports, addresses, and networks (implemented using netfilter ipset) and the option of interface or zone based firewall policy. -.. note:: **Important note on usage of terms:** +.. note:: **Important note on usage of terms:** The firewall makes use of the terms `in`, `out`, and `local` for firewall policy. Users experienced with netfilter often confuse `in` to be a reference to the `INPUT` chain, and `out` the `OUTPUT` @@ -91,35 +91,35 @@ Some firewall settings are global and have an affect on the whole system. .. cfgcmd:: set firewall send-redirects [enable | disable] - enable or disable ICMPv4 redirect messages send by VyOS + enable or disable ICMPv4 redirect messages send by VyOS The following system parameter will be altered: * ``net.ipv4.conf.all.send_redirects`` .. cfgcmd:: set firewall log-martians [enable | disable] - enable or disable the logging of martian IPv4 packets. + enable or disable the logging of martian IPv4 packets. The following system parameter will be altered: * ``net.ipv4.conf.all.log_martians`` .. cfgcmd:: set firewall source-validation [strict | loose | disable] - Set the IPv4 source validation mode. + Set the IPv4 source validation mode. The following system parameter will be altered: * ``net.ipv4.conf.all.rp_filter`` .. cfgcmd:: set firewall syn-cookies [enable | disable] - Enable or Disable if VyOS use IPv4 TCP SYN Cookies. + Enable or Disable if VyOS use IPv4 TCP SYN Cookies. The following system parameter will be altered: * ``net.ipv4.tcp_syncookies`` .. cfgcmd:: set firewall twa-hazards-protection [enable | disable] - Enable or Disable VyOS to be :rfc:`1337` conform. + Enable or Disable VyOS to be :rfc:`1337` conform. The following system parameter will be altered: * ``net.ipv4.tcp_rfc1337`` @@ -135,7 +135,7 @@ Some firewall settings are global and have an affect on the whole system. .. cfgcmd:: set firewall state-policy invalid log enable - Set the global setting for invalid packets. + Set the global setting for invalid packets. .. cfgcmd:: set firewall state-policy related action [accept | drop | reject] @@ -209,7 +209,7 @@ recommended. .. cfgcmd:: set firewall group ipv6-network-group <name> description <text> Provide a IPv4 or IPv6 network group description. - + Port Groups =========== @@ -292,7 +292,7 @@ Matching criteria There are a lot of matching criteria against which the package can be tested. -.. cfgcmd:: set firewall name <name> rule <1-9999> source address +.. cfgcmd:: set firewall name <name> rule <1-9999> source address [address | addressrange | CIDR] .. cfgcmd:: set firewall name <name> rule <1-9999> destination address [address | addressrange | CIDR] @@ -312,16 +312,16 @@ There are a lot of matching criteria against which the package can be tested. set firewall ipv6-name WAN-IN-v6 rule 100 source address 2001:db8::202 -.. cfgcmd:: set firewall name <name> rule <1-9999> source mac-address +.. cfgcmd:: set firewall name <name> rule <1-9999> source mac-address <mac-address> -.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source mac-address +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source mac-address <mac-address> Only in the source criteria, you can specify a mac-address. .. code-block:: none - set firewall name LAN-IN-v4 rule 100 source mac-address 00:53:00:11:22:33 + set firewall name LAN-IN-v4 rule 100 source mac-address 00:53:00:11:22:33 set firewall name LAN-IN-v4 rule 101 source mac-address !00:53:00:aa:12:34 .. cfgcmd:: set firewall name <name> rule <1-9999> source port @@ -344,7 +344,7 @@ There are a lot of matching criteria against which the package can be tested. Multiple source ports can be specified as a comma-separated list. The whole list can also be "negated" using '!'. For example: - + .. code-block:: none set firewall ipv6-name WAN-IN-v6 rule 10 source port '!22,https,3333-3338' @@ -388,7 +388,7 @@ There are a lot of matching criteria against which the package can be tested. <0-255> | all | tcp_udp] Match a protocol criteria. A protocol number or a name which is here - defined: ``/etc/protocols``. + defined: ``/etc/protocols``. Special names are ``all`` for all protocols and ``tcp_udp`` for tcp and udp based packets. The ``!`` negate the selected protocol. @@ -404,7 +404,7 @@ There are a lot of matching criteria against which the package can be tested. Allowed values fpr TCP flags: ``SYN``, ``ACK``, ``FIN``, ``RST``, ``URG``, ``PSH``, ``ALL`` When specifying more than one flag, flags should be comma separated. The ``!`` negate the selected protocol. - + .. code-block:: none set firewall name WAN-IN-v4 rule 10 tcp flags 'ACK' @@ -429,7 +429,7 @@ A Rule-Set can be applied to every interface: * ``out``: Ruleset for forwarded packets on an outbound interface * ``local``: Ruleset for packets destined for this router -.. cfgcmd:: set interface ethernet <ethN> firewall [in | out | local] +.. cfgcmd:: set interface ethernet <ethN> firewall [in | out | local] [name | ipv6-name] <rule-set> Here are some examples for applying a rule-set to an interface @@ -487,7 +487,7 @@ To define a zone setup either one with interfaces or a local zone. Applying a Rule-Set to a Zone ============================= -Before you are able to apply a rule-set to a zone you have to create the zones +Before you are able to apply a rule-set to a zone you have to create the zones first. It helps to think of the syntax as: (see below). The 'rule-set' should be @@ -635,7 +635,7 @@ Rule-set overview .. opcmd:: show firewall statistics This will show you a statistic of all rule-sets since the last boot. - + .. opcmd:: show firewall [name | ipv6name] <name> rule <1-9999> This command will give an overview of a rule in a single rule-set @@ -656,7 +656,7 @@ Rule-set overview 443 8080 8443 - + vyos@vyos:~$ show firewall group LANv4 Name : LANv4 Type : network @@ -781,77 +781,3 @@ Example Partial Config } } } - - -.. _routing-mss-clamp: - - -**************** -TCP-MSS Clamping -**************** - -As Internet wide PMTU discovery rarely works, we sometimes need to clamp -our TCP MSS value to a specific value. This is a field in the TCP -Options part of a SYN packet. By setting the MSS value, you are telling -the remote side unequivocally 'do not try to send me packets bigger than -this value'. - -Starting with VyOS 1.2 there is a firewall option to clamp your TCP MSS -value for IPv4 and IPv6. - - -.. note:: MSS value = MTU - 20 (IP header) - 20 (TCP header), resulting - in 1452 bytes on a 1492 byte MTU. - - - -IPv4 -==== - - -.. cfgcmd:: set firewall options interface <interface> adjust-mss - <number-of-bytes> - - Use this command to set the maximum segment size for IPv4 transit - packets on a specific interface (500-1460 bytes). - -Example -------- - -Clamp outgoing MSS value in a TCP SYN packet to `1452` for `pppoe0` and -`1372` -for your WireGuard `wg02` tunnel. - -.. code-block:: none - - set firewall options interface pppoe0 adjust-mss '1452' - set firewall options interface wg02 adjust-mss '1372' - - - -IPv6 -==== - -.. cfgcmd:: set firewall options interface <interface> adjust-mss6 - <number-of-bytes> - - Use this command to set the maximum segment size for IPv6 transit - packets on a specific interface (1280-1492 bytes). - -.. _firewall:ipv6_example: - -Example -------- - -Clamp outgoing MSS value in a TCP SYN packet to `1280` for both `pppoe0` and -`wg02` interface. - -.. code-block:: none - - set firewall options interface pppoe0 adjust-mss6 '1280' - set firewall options interface wg02 adjust-mss6 '1280' - - - -.. hint:: When doing your byte calculations, you might find useful this - `Visual packet size calculator <https://baturin.org/tools/encapcalc/>`_. |