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diff --git a/docs/configuration/firewall/index.rst b/docs/configuration/firewall/index.rst new file mode 100644 index 00000000..870e9a08 --- /dev/null +++ b/docs/configuration/firewall/index.rst @@ -0,0 +1,767 @@ +.. _firewall: + +Firewall +======== + +Overview +-------- + +VyOS makes use of Linux `netfilter <https://netfilter.org/>`_ for packet +filtering. + +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:** + 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` + chain from netfilter. This is not the case. These instead indicate + the use of the `FORWARD` chain and either the input or output + interface. The `INPUT` chain, which is used for local traffic to the + OS, is a reference to as `local` with respect to its input interface. + + +Global settings +--------------- + +Some firewall settings are global and have a affect on the whole system. + +.. cfgcmd:: set firewall all-ping [enable | disable] + + By default, when VyOS receives an ICMP echo request packet destined for + itself, it will answer with an ICMP echo reply, unless you avoid it + through its firewall. + + With the firewall you can set rules to accept, drop or reject ICMP in, + out or local traffic. You can also use the general **firewall all-ping** + command. This command affects only to LOCAL (packets destined for your + VyOS system), not to IN or OUT traffic. + + .. note:: **firewall all-ping** affects only to LOCAL and it always + behaves in the most restrictive way + + .. code-block:: none + + set firewall all-ping enable + + When the command above is set, VyOS will answer every ICMP echo request + addressed to itself, but that will only happen if no other rule is + applied dropping or rejecting local echo requests. In case of conflict, + VyOS will not answer ICMP echo requests. + + .. code-block:: none + + set firewall all-ping disable + + When the command above is set, VyOS will answer no ICMP echo request + addressed to itself at all, no matter where it comes from or whether + more specific rules are being applied to accept them. + +.. cfgcmd:: set firewall broadcast-ping [enable | disable] + + This setting enable or disable the response of icmp broadcast + messages. The following system parameter will be altered: + + * ``net.ipv4.icmp_echo_ignore_broadcasts`` + +.. cfgcmd:: set firewall ip-src-route [enable | disable] +.. cfgcmd:: set firewall ipv6-src-route [enable | disable] + + This setting handle if VyOS accept packets with a source route + option. The following system parameter will be altered: + + * ``net.ipv4.conf.all.accept_source_route`` + * ``net.ipv6.conf.all.accept_source_route`` + +.. cfgcmd:: set firewall receive-redirects [enable | disable] +.. cfgcmd:: set firewall ipv6-receive-redirects [enable | disable] + + enable or disable of ICMPv4 or ICMPv6 redirect messages accepted + by VyOS. The following system parameter will be altered: + + * ``net.ipv4.conf.all.accept_redirects`` + * ``net.ipv6.conf.all.accept_redirects`` + +.. cfgcmd:: set firewall send-redirects [enable | disable] + + enable or disable of 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. + 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. + 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. + 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. + The following system parameter will be altered: + + * ``net.ipv4.tcp_rfc1337`` + +.. cfgcmd:: set firewall state-policy established action [accept | drop | + reject] + +.. cfgcmd:: set firewall state-policy established log enable + + Set the global setting for a astablished connections. + +.. cfgcmd:: set firewall state-policy invalid action [accept | drop | reject] + +.. cfgcmd:: set firewall state-policy invalid log enable + + Set the global setting for invalid packets. + +.. cfgcmd:: set firewall state-policy related action [accept | drop | reject] + +.. cfgcmd:: set firewall state-policy related log enable + + Set the global setting for related connections. + + +Groups +------ + +Firewall groups represent collections of IP addresses, networks, or +ports. Once created, a group can be referenced by firewall rules as +either a source or destination. Members can be added or removed from a +group without changes to, or the need to reload, individual firewall +rules. + +.. note:: Groups can also be referenced by NAT configuration. + +Groups need to have unique names. Even though some contain IPv4 +addresses and others contain IPv6 addresses, they still need to have +unique names, so you may want to append "-v4" or "-v6" to your group +names. + + +Address Groups +************** + +In a **address group** a single IP adresses or IP address ranges are +definded. + +.. cfgcmd:: set firewall group address-group <name> address [address | + address range] +.. cfgcmd:: set firewall group ipv6-address-group <name> address <address> + + Define a IPv4 or a IPv6 address group + + .. code-block:: none + + set firewall group address-group ADR-INSIDE-v4 address 192.168.0.1 + set firewall group address-group ADR-INSIDE-v4 address 10.0.0.1-10.0.0.8 + set firewall group ipv6-address-group ADR-INSIDE-v6 address 2001:db8::1 + +.. cfgcmd:: set firewall group address-group <name> description <text> +.. cfgcmd:: set firewall group ipv6-address-group <name> description <text> + + Provide a IPv4 or IPv6 address group description + + +Network Groups +************** + +While **network groups** accept IP networks in CIDR notation, specific +IP addresses can be added as a 32-bit prefix. If you foresee the need +to add a mix of addresses and networks, the network group is +recommended. + +.. cfgcmd:: set firewall group network-group <name> network <CIDR> +.. cfgcmd:: set firewall group ipv6-network-group <name> network <CIDR> + + Define a IPv4 or IPv6 Network group. + + .. code-block:: none + + set firewall group network-group NET-INSIDE-v4 network 192.168.0.0/24 + set firewall group network-group NET-INSIDE-v4 network 192.168.1.0/24 + set firewall group ipv6-network-group NET-INSIDE-v6 network 2001:db8::/64 + +.. cfgcmd:: set firewall group network-group <name> description <text> +.. cfgcmd:: set firewall group ipv6-network-group <name> description <text> + + Provide a IPv4 or IPv6 network group description. + + +Port Groups +*********** + +A **port group** represents only port numbers, not the protocol. Port +groups can be referenced for either TCP or UDP. It is recommended that +TCP and UDP groups are created separately to avoid accidentally +filtering unnecessary ports. Ranges of ports can be specified by using +`-`. + +.. cfgcmd:: set firewall group port-group <name> port + [portname | portnumber | startport-endport] + + Define a port group. A port name are any name defined in + /etc/services. e.g.: http + + .. code-block:: none + + set firewall group port-group PORT-TCP-SERVER1 port http + set firewall group port-group PORT-TCP-SERVER1 port 443 + set firewall group port-group PORT-TCP-SERVER1 port 5000-5010 + +.. cfgcmd:: set firewall group port-group <name> description <text> + + Provide a port group description. + + +Rule-Sets +---------- + +A rule-set is a named collection of firewall rules that can be applied +to an interface or zone. Each rule is numbered, has an action to apply +if the rule is matched, and the ability to specify the criteria to +match. Data packets go through the rules from 1 - 9999, at the first match +the action of the rule will executed. + +.. cfgcmd:: set firewall name <name> description <text> +.. cfgcmd:: set firewall ipv6-name <name> description <text> + + Provide a rule-set description. + +.. cfgcmd:: set firewall name <name> default-action [drop | reject | accept] +.. cfgcmd:: set firewall ipv6-name <name> default-action [drop | reject | + accept] + + This set the default action of the rule-set if no rule matched a paket + criteria. + +.. cfgcmd:: set firewall name <name> enable-default-log +.. cfgcmd:: set firewall ipv6-name <name> enable-default-log + + Use this command to enable the logging of the default action. + +.. cfgcmd:: set firewall name <name> rule <1-9999> action [drop | reject | + accept] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> action [drop | reject | + accept] + + This required setting define the action of the current rule. + +.. cfgcmd:: set firewall name <name> rule <1-9999> description <text> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> description <text> + + Provide a description for each rule. + +.. cfgcmd:: set firewall name <name> rule <1-9999> log [disable | enable] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> log [disable | enable] + + Enable or disable logging for the matched packet. + +.. cfgcmd:: set firewall name <name> rule <1-9999> disable +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> disable + + If you want to disable a rule but let it in the configuration. + +Matching criteria +***************** + +There are a lot of matching criteria gainst which the package can be tested. + + +.. 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] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source address + [address | addressrange | CIDR] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> destination address + [address | addressrange | CIDR] + + This is similiar to the network groups part, but here you are able to negate + the matching addresses. + + .. code-block:: none + + set firewall name WAN-IN-v4 rule 100 source address 192.0.2.10-192.0.2.11 + # with a '!' the rule match everything except the specified subnet + set fitewall name WAN-IN-v4 rule 101 source address !203.0.113.0/24 + 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 + <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 101 source mac-address !00:53:00:aa:12:34 + +.. cfgcmd:: set firewall name <name> rule <1-9999> source port + [1-65535 | portname | start-end] +.. cfgcmd:: set firewall name <name> rule <1-9999> destination port + [1-65535 | portname | start-end] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source port + [1-65535 | portname | start-end] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> destination port + [1-65535 | portname | start-end] + + A port can be set with a portnumber or a name which is here + defined: ``/etc/services``. + + .. code-block:: none + + set firewall name WAN-IN-v4 rule 10 source port '22' + set firewall name WAN-IN-v4 rule 11 source port '!http' + set firewall name WAN-IN-v4 rule 12 source port 'https' + + 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' + +.. cfgcmd:: set firewall name <name> rule <1-9999> source group + address-group <name> +.. cfgcmd:: set firewall name <name> rule <1-9999> destination group + address-group <name> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source group + address-group <name> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> destination group + address-group <name> + + Use a specific address-group + +.. cfgcmd:: set firewall name <name> rule <1-9999> source group + network-group <name> +.. cfgcmd:: set firewall name <name> rule <1-9999> destination group + network-group <name> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source group + network-group <name> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> destination group + network-group <name> + + Use a specific network-group + +.. cfgcmd:: set firewall name <name> rule <1-9999> source group + port-group <name> +.. cfgcmd:: set firewall name <name> rule <1-9999> destination group + port-group <name> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> source group + port-group <name> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> destination group + port-group <name> + + Use a specific port-group + +.. cfgcmd:: set firewall name <name> rule <1-9999> protocol [<text> | + <0-255> | all | tcp_udp] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> protocol [<text> | + <0-255> | all | tcp_udp] + + Match a protocol criteria. A protocol number or a name which is here + defined: ``/etc/protocols``. + Special names are ``all`` for all protocols and ``tcp_udp`` for tcp and upd + based pakets. The ``!`` negate the selected protocol. + + .. code-block:: none + + set firewall name WAN-IN-v4 rule 10 protocol tcp_udp + set firewall name WAN-IN-v4 rule 11 protocol !tcp_udp + set firewall ipv6-name WAN-IN-v6 rule 10 protocol tcp + +.. cfgcmd:: set firewall name <name> rule <1-9999> tcp flags <text> +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> tcp flags <text> + + 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' + set firewall name WAN-IN-v4 rule 12 tcp flags 'SYN' + set firewall name WAN-IN-v4 rule 13 tcp flags 'SYN,!ACK,!FIN,!RST' + +.. cfgcmd:: set firewall name <name> rule <1-9999> state [established | + invalid | new | related] [enable | disable ] +.. cfgcmd:: set firewall ipv6-name <name> rule <1-9999> state [established | + invalid | new | related] [enable | disable ] + + Match against the state of a packet. + + +Applying a Rule-Set to an Interface +----------------------------------- + +A Rule-Set can be appliend to every inteface: + +* ``in``: Ruleset for forwarded packets on inbound interface +* ``out``: Ruleset for forwarded packets on outbound interface +* ``local``: Ruleset for packets destined for this router + +.. 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 + + .. code-block:: none + + set interface ethernet eth1 vif 100 firewall in name LANv4-IN + set interface ethernet eth1 vif 100 firewall out name LANv4-OUT + set interface bonding bond0 firewall in name LANv4-IN + set interfaces openvpn vtun1 firewall in name Lanv4-IN + + .. note:: + As you can see in the example here, you can assign the same rule-set to + several interfaces. An interface can only have one rule-set per chain. + + +Zone-based Firewall Policy +-------------------------- + +As an alternative to applying policy to an interface directly, a +zone-based firewall can be created to simplify configuration when +multiple interfaces belong to the same security zone. Instead of +applying rulesets to interfaces, they are applied to source +zone-destination zone pairs. + +An basic introduction to zone-based firewalls can be found `here +<https://support.vyos.io/en/kb/articles/a-primer-to-zone-based-firewall>`_, +and an example at :ref:`examples-zone-policy`. + +Define a Zone +************* + +To define a zone setup either one with interfaces or a local zone. + +.. cfgcmd:: set zone-policy zone <name> interface <interfacenames> + + Set a interfaces to a zone. A zone can have multiple interfaces. + But a interface can only be member in one zone. + +.. cfgcmd:: set zone-policy zone <name> local-zone + + Define the Zone as a local zone. A local zone have no interfaces and + will be applied to the router itself. + +.. cfgcmd:: set zone-policy zone <name> default-action [drop | reject] + + Change the default-action with this setting. + +.. cfgcmd:: set zone-policy zone <name> description + + Set a meaningful description. + + +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 +first. + +.. cfgcmd:: set zone-policy zone <name> from <name> firewall name + <rule-set> +.. cfgcmd:: set zone-policy zone <name> from <name> firewall ipv6-name + <rule-set> + + You apply a rule-set always to a zone from a other zone, it is recommended + to create one rule-set for each zone pair. + + .. code-block:: none + + set zone-policy zone DMZ from LAN firewall name LANv4-to-DMZv4 + set zone-policy zone LAN from DMZ firewall name DMZv4-to-LANv4 + + +Operation-mode Firewall +----------------------- + +Rule-set overview +***************** + +.. opcmd:: show firewall + + This will show you a basic firewall overview + + .. code-block:: none + + vyos@vyos:~$ show firewall + + ------------------------ + Firewall Global Settings + ------------------------ + + Firewall state-policy for all IPv4 and Ipv6 traffic + + state action log + ----- ------ --- + invalid accept disabled + established accept disabled + related accept disabled + + ----------------------------- + Rulesets Information + ----------------------------- + -------------------------------------------------------------------------- + IPv4 Firewall "DMZv4-1-IN": + + Active on (eth0,IN) + + rule action proto packets bytes + ---- ------ ----- ------- ----- + 10 accept icmp 0 0 + condition - saddr 10.1.0.0/24 daddr 0.0.0.0/0 LOG enabled + + 10000 drop all 0 0 + condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 LOG enabled + + -------------------------------------------------------------------------- + IPv4 Firewall "DMZv4-1-OUT": + + Active on (eth0,OUT) + + rule action proto packets bytes + ---- ------ ----- ------- ----- + 10 accept tcp_udp 1 60 + condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 match-DST-PORT-GROUP DMZ-Ports /* + DMZv4-1-OUT-10 */LOG enabled + + 11 accept icmp 1 84 + condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 /* DMZv4-1-OUT-11 */LOG enabled + + 10000 drop all 6 360 + condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 LOG enabled + + -------------------------------------------------------------------------- + IPv4 Firewall "LANv4-IN": + + Inactive - Not applied to any interfaces or zones. + + rule action proto packets bytes + ---- ------ ----- ------- ----- + 10 accept all 0 0 + condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 /* LANv4-IN-10 */ + + 10000 drop all 0 0 + condition - saddr 0.0.0.0/0 daddr 0.0.0.0/0 + +.. opcmd:: show firewall summary + + This will show you a summary about rule-sets and groups + + .. code-block:: none + + vyos@vyos:~$ show firewall summary + + ------------------------ + Firewall Global Settings + ------------------------ + + Firewall state-policy for all IPv4 and Ipv6 traffic + + state action log + ----- ------ --- + invalid accept disabled + related accept disabled + established accept disabled + + ------------------------ + Firewall Rulesets + ------------------------ + + IPv4 name: + + Rule-set name Description References + ------------- ----------- ---------- + DMZv4-1-OUT (eth0,OUT) + DMZv4-1-IN (eth0,IN) + + ------------------------ + Firewall Groups + ------------------------ + + Port Groups: + + Group name Description References + ---------- ----------- ---------- + DMZ-Ports DMZv4-1-OUT-10-destination + + Network Groups: + + Group name Description References + ---------- ----------- ---------- + LANv4 LANv4-IN-10-source, + DMZv4-1-OUT-10-source, + DMZv4-1-OUT-11-source + +.. 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 about a rule in a single rule-set + +.. opcmd:: show firewall group <name> + + Overview of defined groups. You see the type, the members, and where the + group is used. + + .. code-block:: none + + vyos@vyos:~$ show firewall group DMZ-Ports + Name : DMZ-Ports + Type : port + References : none + Members : + 80 + 443 + 8080 + 8443 + + vyos@vyos:~$ show firewall group LANv4 + Name : LANv4 + Type : network + References : LANv4-IN-10-source + Members : + 10.10.0.0/16 + +.. opcmd:: show firewall [name | ipv6name] <name> + + This command will give an overview about a single rule-set + +.. opcmd:: show firewall [name | ipv6name] <name> statistics + + This will show you a rule-set statistic since the last boot. + +.. opcmd:: show firewall [name | ipv6name] <name> rule <1-9999> + + This command will give an overview about a rule in a single rule-set + + +Zone-Policy Overview +******************** + +.. opcmd:: show zone-policy zone <name> + + Use this command to get an overview about a zone + + .. code-block:: none + + vyos@vyos:~$ show zone-policy zone DMZ + ------------------- + Name: DMZ + + Interfaces: eth0 eth1 + + From Zone: + name firewall + ---- -------- + LAN DMZv4-1-OUT + + +Show Firewall log +***************** + +.. opcmd:: show log firewall [name | ipv6name] <name> + + Show the logs of a specific Rule-Set + +.. note:: + At the moment it not possible to look at the whole firewall log with VyOS + operational commands. All logs will save to ``/var/logs/messages``. + For example: ``grep '10.10.0.10' /var/log/messages`` + + + +Example Partial Config +---------------------- + +.. code-block:: none + + firewall { + all-ping enable + broadcast-ping disable + config-trap disable + group { + network-group BAD-NETWORKS { + network 198.51.100.0/24 + network 203.0.113.0/24 + } + network-group GOOD-NETWORKS { + network 192.0.2.0/24 + } + port-group BAD-PORTS { + port 65535 + } + } + name FROM-INTERNET { + default-action accept + description "From the Internet" + rule 10 { + action accept + description "Authorized Networks" + protocol all + source { + group { + network-group GOOD-NETWORKS + } + } + } + rule 11 { + action drop + description "Bad Networks" + protocol all + source { + group { + network-group BAD-NETWORKS + } + } + } + rule 30 { + action drop + description "BAD PORTS" + destination { + group { + port-group BAD-PORTS + } + } + log enable + protocol all + } + } + } + interfaces { + ethernet eth1 { + address dhcp + description OUTSIDE + duplex auto + firewall { + in { + name FROM-INTERNET + } + } + } + } |