firewalld.richlang (5)

NAME

DESCRIPTION

Rule
Source
Destination
Service
Port
Protocol
ICMP-Block
Masquerade
Forward-Port
Log
Audit
Action
Information about logging and actions

EXAMPLES

Example 1
Example 2
Example 3
Example 4
Example 5
Example 6
Example 7
Example 8

SEE ALSO

NOTES

AUTHORS

NAME

firewalld.richlanguage - Rich Language Documentation

DESCRIPTION

With the rich language more complex firewall rules can be created in an easy to understand way. The language will use keywords with values and will be an abstract representation of ip*tables rules. Zones can be configured using this language, the current configuration will still be supported.

The rich language extends the current zone elements (service, port, icmp-block, masquerade and forward-port) with additional source and destination addresses, logging, actions and limits for logs and actions.

This page describes the rich language used in the command line client and D-Bus interface. For information about the rich language representation used in the zone configuration files, please have a look at firewalld.zone(5).

A rule is part of a zone. A zone can contain several rules. If some rules interact/contradict, the first rule that matches "wins".

General rule structure

rule
  [source]
  [destination]
  service|port|protocol|icmp-block|masquerade|forward-port
  [log]
  [audit]
  [accept|reject|drop]

The complete rule is provided as a single line string. A destination is allowed here as long as it does not conflict with the destination of a service and is not allowed for masquerade at all.

Rule structure for source black or white listing

rule
  source
  [log]
  [audit]
  accept|reject|drop

This is used to grant or limit access from a source to this machine or machines that are reachable by this machine. A destination is not allowed here.

Important information about element options: Options for elements in a rule need to be added exactly after the element. If the option is placed somewhere else it might be used for another element as far as it matches the options of the other element or will result in a rule error.

Rule

rule [family="ipv4|ipv6"]

If the rule family is provided, it can be either "ipv4" or "ipv6", which limits the rule to IPv4 or IPv6. If the rule family is not provided, the rule will be added for IPv4 and IPv6. If source or destination addresses are used in a rule, then the rule family need to be provided. This is also the case for port/packet forwarding.

Source

source address="address[/mask]" [invert="True"]

With the source address the origin of a connection attempt can be limited to the source address. A source address or address range is either an IP address or a network IP address with a mask for IPv4 or IPv6. The network family (IPv4/IPv6) will be automatically discovered. For IPv4, the mask can be a network mask or a plain number. For IPv6 the mask is a plain number. The use of host names is not supported. It is possible to invert the sense of an address by adding invert="true" or invert="yes". All but the used address with match.

Destination

destination address="address[/mask]" invert="True"

With the destination address the target can be limited to the destination address. The destination address is using the same syntax as the source address.

The use of source and destination addresses is optional and the use of a destination addresses is not possible with all elements. This depends on the use of destination addresses for example in service entries.

Service

service name="service name"

The service service name will be added to the rule. The service name is one of the firewalld provided services. To get a list of the supported services, use firewall-cmd --get-services.

If a service provides a destination address, it will conflict with a destination address in the rule and will result in an error. The services using destination addresses internally are mostly services using multicast.

Port

port port="port value" protocol="tcp|udp"

The port port value can either be a single port number portid or a port range portid-portid. The protocol can either be tcp or udp.

Protocol

protocol value="protocol value"

The protocol value can be either a protocol id number or a protocol name. For allowed protocol entries, please have a look at /etc/protocols.

ICMP-Block

icmp-block name="icmptype name"

The icmptype is the one of the icmp types firewalld supports. To get a listing of supported icmp types: firewall-cmd --get-icmptypes

It is not allowed to specify an action here. icmp-block uses the action reject internally.

Masquerade

masquerade

Turn on masquerading in the rule. A source address can be provided to limit masquerading to this area, but not a destination address.

It is not allowed to specify an action here.

Forward-Port

forward-port port="port value" protocol="tcp|udp" to-port="port value" to-addr="address"

Forward port/packets from local port value with protocol "tcp" or "udp" to either another port locally or to another machine or to another port on another machine.

The port value can either be a single port number or a port range portid-portid. The destination address is an IP address.

It is not allowed to specify an action here. forward-port uses the action accept internally.

Log

log [prefix="prefix text"] [level="log level"] [limit value="rate/duration"]

Log new connection attempts to the rule with kernel logging for example in syslog. You can define a prefix text that will be added to the log message as a prefix. Log level can be one of "emerg", "alert", "crit", "error", "warning", "notice", "info" or "debug". See syslog(3) for description of levels.

It is possible to limit logging: The rate is a natural positive number [1, ..], the duration is of "s", "m", "h", "d". "s" means seconds, "m" minutes, "h" hours and "d" days. The maximum limit value is "1/d" which means at maximum one log entry per day.

Audit

Audit provides an alternative way for logging using audit records sent to the service auditd. The audit type will be discovered from the rule action automatically. The use of audit is optional.

Also audit can be limited using the limit tag.

Action

An action can be one of accept, reject or drop.

The rule can either contain an element or also a source only. If the rule contains an element, then new connection matching the element will be handled with the action. If the rule does not contain an element, then everything from the source address will be handled with the action (requires firewalld version 0.3.1).

accept | reject [type="reject type"] | drop

With accept all new connection attempts will be granted. With reject they will not be accepted and there source will get a reject message. The reject type can be set to use an other value. With drop all packets will be dropped immediately, there is no information sent to the source.

Also an action can be limited using the limit tag.

Information about logging and actions

Logging can be done with the log and also with audit. A new chain is added to all zones: zone_log. This will be jumped into before the deny chain to be able to have a proper ordering.

The rules or parts of them are placed in separate chains according to the action of the rule:

zone_log
zone_deny
zone_allow

Then all logging rules will be placed in the zone_log chain, which will be walked first. All reject and drop rules will be placed in the zone_deny chain, which will be walked after the log chain. All accept rules will be placed in the zone_allow chain, which will be walked after the deny chain. If a rule contains log and also deny or allow actions, the parts are placed in the matching chains.

EXAMPLES

These are examples of how to specify rich language rules. This format (i.e. one string that specifies whole rule) uses for example firewall-cmd --add-rich-rule (see firewall-cmd(1)) as well as D-Bus interface.

Example 1

Enable new IPv4 and IPv6 connections for protocol 'ah'

rule protocol value="ah" accept

Example 2

Allow new IPv4 and IPv6 connections for service ftp and log 1 per minute using audit

rule service name="ftp" log limit value="1/m" audit accept

Example 3

Allow new IPv4 connections from address 192.168.0.0/24 for service tftp and log 1 per minutes using syslog

rule family="ipv4" source address="192.168.0.0/24" service name="tftp" log prefix="tftp" level="info" limit value="1/m" accept

Example 4

New IPv6 connections from 1:2:3:4:6:: to service radius are all rejected and logged at a rate of 3 per minute. New IPv6 connections from other sources are accepted.

rule family="ipv6" source address="1:2:3:4:6::" service name="radius" log prefix="dns" level="info" limit value="3/m" reject
rule family="ipv6" service name="radius" accept

Example 5

Forward IPv6 port/packets receiving from 1:2:3:4:6:: on port 4011 with protocol tcp to 1::2:3:4:7 on port 4012

rule family="ipv6" source address="1:2:3:4:6::" forward-port to-addr="1::2:3:4:7" to-port="4012" protocol="tcp" port="4011"

Example 6

White-list source address to allow all connections from 192.168.2.2

rule family="ipv4" source address="192.168.2.2" accept

Example 7

Black-list source address to reject all connections from 192.168.2.3

rule family="ipv4" source address="192.168.2.3" reject

Example 8

Black-list source address to drop all connections from 192.168.2.4

rule family="ipv4" source address="192.168.2.4" drop

NOTES

firewalld home page at fedorahosted.org:

: m[blue]http://fedorahosted.org/firewalld/m[]

AUTHORS

Thomas Woerner <twoerner@redhat.com>

: Developer

Jiri Popelka <jpopelka@redhat.com>

: Developer