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+.. _examples-zone-policy:
+
+Zone-Policy example
+-------------------
+
+Native IPv4 and IPv6
+^^^^^^^^^^^^^^^^^^^^
+
+We have three networks.
+
+.. code-block:: sh
+
+ WAN - 172.16.10.0/24, 2001:0DB8:0:9999::0/64
+ LAN - 192.168.100.0/24, 2001:0DB8:0:AAAA::0/64
+ DMZ - 192.168.200.0/24, 2001:0DB8:0:BBBB::0/64
+
+
+This specific example is for a router on a stick, but is very easily adapted
+for however many NICs you have.
+
+[http://imgur.com/Alz1J.png Topology Image]
+
+The VyOS interface is assigned the .1/:1 address of their respective networks.
+WAN is on VLAN 10, LAN on VLAN 20, and DMZ on VLAN 30.
+
+It will look something like this:
+
+.. code-block:: sh
+
+ interfaces {
+ ethernet eth0 {
+ duplex auto
+ hw-id 00:0c:29:6e:2a:92
+ smp_affinity auto
+ speed auto
+ vif 10 {
+ address 172.16.10.1/24
+ address 2001:db8:0:9999::1/64
+ }
+ vif 20 {
+ address 192.168.100.1/24
+ address 2001:db8:0:AAAA::1/64
+ }
+ vif 30 {
+ address 192.168.200.1/24
+ address 2001:db8:0:BBBB::1/64
+ }
+ }
+ loopback lo {
+ }
+ }
+
+
+Zones Basics
+^^^^^^^^^^^^
+
+Each interface is assigned to a zone. The interface can be physical or virtual
+such as tunnels (VPN, pptp, gre, etc) and are treated exactly the same.
+
+Traffic flows from zone A to zone B. That flow is what I refer to as a
+zone-pair-direction. eg. A->B and B->A are two zone-pair-destinations.
+
+Ruleset are created per zone-pair-direction.
+
+I name rule sets to indicate which zone-pair-direction they represent. eg.
+ZoneA-ZoneB or ZoneB-ZoneA. LAN-DMZ, DMZ-LAN.
+
+In VyOS, you have to have unique Ruleset names. In the event of overlap, I
+add a "-6" to the end of v6 rulesets. eg. LAN-DMZ, LAN-DMZ-6. This allows for
+each auto-completion and uniqueness.
+
+In this example we have 4 zones. LAN, WAN, DMZ, Local. The local zone is the
+firewall itself.
+
+If your computer is on the LAN and you need to SSH into your VyOS box, you
+would need a rule to allow it in the LAN-Local ruleset. If you want to access
+a webpage from your VyOS box, you need a rule to allow it in the Local-LAN
+ruleset.
+
+In rules, it is good to keep them named consistently. As the number of rules
+you have grows, the more consistency you have, the easier your life will be.
+
+.. code-block:: sh
+
+ Rule 1 - State Established, Related
+ Rule 2 - State Invalid
+ Rule 100 - ICMP
+ Rule 200 - Web
+ Rule 300 - FTP
+ Rule 400 - NTP
+ Rule 500 - SMTP
+ Rule 600 - DNS
+ Rule 700 - DHCP
+ Rule 800 - SSH
+ Rule 900 - IMAPS
+
+The first two rules are to deal with the idiosyncrasies of VyOS and iptables.
+
+Zones and Rulesets both have a default action statement. When using
+Zone-Policies, the default action is set by the zone-policy statement and is
+represented by rule 10000.
+
+It is good practice to log both accepted and denied traffic. It can save you
+significant headaches when trying to troubleshoot a connectivity issue.
+
+To add logging to the default rule, do:
+
+.. code-block:: sh
+
+ set firewall name <ruleSet> enable-default-log
+
+
+By default, iptables does not allow traffic for established session to return,
+so you must explicitly allow this. I do this by adding two rules to every
+ruleset. 1 allows established and related state packets through and rule 2
+drops and logs invalid state packets. We place the established/related rule at
+the top because the vast majority of traffic on a network is established and
+the invalid rule to prevent invalid state packets from mistakenly being matched
+against other rules. Having the most matched rule listed first reduces CPU load
+in high volume environments. Note: I have filed a bug to have this added as a
+default action as well.
+
+''It is important to note, that you do not want to add logging to the
+established state rule as you will be logging both the inbound and outbound
+packets for each session instead of just the initiation of the session.
+Your logs will be massive in a very short period of time.''
+
+In VyOS you must have the interfaces created before you can apply it to the
+zone and the rulesets must be created prior to applying it to a zone-policy.
+
+I create/configure the interfaces first. Build out the rulesets for each
+zone-pair-direction which includes at least the three state rules. Then I setup
+the zone-policies.
+
+Zones do not allow for a default action of accept; either drop or reject.
+It is important to remember this because if you apply an interface to a zone
+and commit, any active connections will be dropped. Specifically, if you are
+SSH’d into VyOS and add local or the interface you are connecting through to a
+zone and do not have rulesets in place to allow SSH and established sessions,
+you will not be able to connect.
+
+The following are the rules that were created for this example
+(may not be complete), both in IPv4 and IPv6. If there is no IP specified,
+then the source/destination address is not explicit.
+
+.. code-block:: sh
+
+ WAN – DMZ:192.168.200.200 – tcp/80
+ WAN – DMZ:192.168.200.200 – tcp/443
+ WAN – DMZ:192.168.200.200 – tcp/25
+ WAN – DMZ:192.168.200.200 – tcp/53
+ WAN – DMZ:2001:0DB8:0:BBBB::200 – tcp/80
+ WAN – DMZ:2001:0DB8:0:BBBB::200 – tcp/443
+ WAN – DMZ:2001:0DB8:0:BBBB::200 – tcp/25
+ WAN – DMZ:2001:0DB8:0:BBBB::200 – tcp/53
+
+ DMZ - Local - tcp/53
+ DMZ - Local - tcp/123
+ DMZ - Local - tcp/67,68
+
+ LAN - Local - tcp/53
+ LAN - Local - tcp/123
+ LAN - Local - tcp/67,68
+ LAN:192.168.100.10 - Local - tcp/22
+ LAN:2001:0DB8:0:AAAA::10 - Local - tcp/22
+
+ LAN - WAN - tcp/80
+ LAN - WAN - tcp/443
+ LAN - WAN - tcp/22
+ LAN - WAN - tcp/20,21
+
+ DMZ - WAN - tcp/80
+ DMZ - WAN - tcp/443
+ DMZ - WAN - tcp/22
+ DMZ - WAN - tcp/20,21
+ DMZ - WAN - tcp/53
+ DMZ - WAN - udp/53
+
+ Local - WAN - tcp/80
+ Local - WAN - tcp/443
+ Local - WAN - tcp/20,21
+
+ Local - DMZ - tcp/25
+ Local - DMZ - tcp/67,68
+ Local - DMZ - tcp/53
+ Local - DMZ - udp/53
+
+ Local - LAN - tcp/67,68
+
+ LAN - DMZ - tcp/80
+ LAN - DMZ - tcp/443
+ LAN - DMZ - tcp/993
+ LAN:2001:0DB8:0:AAAA::10 - DMZ:2001:0DB8:0:BBBB::200 - tcp/22
+ LAN:192.168.100.10 - DMZ:192.168.200.200 - tcp/22
+
+Since we have 4 zones, we need to setup the following rulesets.
+
+.. code-block:: sh
+
+ Lan-wan
+ Lan-local
+ Lan-dmz
+ Wan-lan
+ Wan-local
+ Wan-dmz
+ Local-lan
+ Local-wan
+ Local-dmz
+ Dmz-lan
+ Dmz-wan
+ Dmz-local
+
+Even if the two zones will never communicate, it is a good idea to create the
+zone-pair-direction rulesets and set enable-default-log. This will allow you to
+log attempts to access the networks. Without it, you will never see the
+connection attempts.
+
+This is an example of the three base rules.
+
+.. code-block:: sh
+
+ name wan-lan {
+ default-action drop
+ enable-default-log
+ rule 1 {
+ action accept
+ state {
+ established enable
+ related enable
+ }
+ }
+ rule 2 {
+ action drop
+ log enable
+ state {
+ invalid enable
+ }
+ }
+ }
+
+
+Here is an example of an IPv6 DMZ-WAN ruleset.
+
+.. code-block:: sh
+
+ ipv6-name dmz-wan-6 {
+ default-action drop
+ enable-default-log
+ rule 1 {
+ action accept
+ state {
+ established enable
+ related enable
+ }
+ }
+ rule 2 {
+ action drop
+ log enable
+ state {
+ invalid enable
+ }
+ rule 100 {
+ action accept
+ log enable
+ protocol ipv6-icmp
+ }
+ rule 200 {
+ action accept
+ destination {
+ port 80,443
+ }
+ log enable
+ protocol tcp
+ }
+ rule 300 {
+ action accept
+ destination {
+ port 20,21
+ }
+ log enable
+ protocol tcp
+ }
+ rule 500 {
+ action accept
+ destination {
+ port 25
+ }
+ log enable
+ protocol tcp
+ source {
+ address 2001:db8:0:BBBB::200
+ }
+ }
+ rule 600 {
+ action accept
+ destination {
+ port 53
+ }
+ log enable
+ protocol tcp_udp
+ source {
+ address 2001:db8:0:BBBB::200
+ }
+ }
+ rule 800 {
+ action accept
+ destination {
+ port 22
+ }
+ log enable
+ protocol tcp
+ }
+ }
+
+Once you have all of your rulesets built, then you need to create your
+zone-policy.
+
+Start by setting the interface and default action for each zone.
+
+.. code-block:: sh
+
+ set zone-policy zone dmz default-action drop
+ set zone-policy zone dmz interface eth0.30
+
+In this case, we are setting the v6 ruleset that represents traffic sourced
+from the LAN, destined for the DMZ.
+Because the zone-policy firewall syntax is a little awkward, I keep it straight
+by thinking of it backwards.
+
+ set zone-policy zone dmz from lan firewall ipv6-name lan-dmz-6
+
+dmz-lan policy is lan-dmz. You can get a rhythm to it when you build out a bunch at one time.
+
+In the end, you will end up with something like this config. I took out everything but the Firewall, Interfaces, and zone-policy sections. It is long enough as is.
+== IPv6 Tunnel ==
+
+If you are using a IPv6 tunnel from HE.net or someone else, the basis is the same except you have two WAN interface. One for v4 and one for v6.
+
+You would have 5 zones instead of just 4 and you would configure your v6 ruleset between your tunnel interface and your LAN/DMZ zones instead of to the WAN.
+
+LAN, WAN, DMZ, local and TUN (tunnel)
+
+v6 pairs would be:
+
+.. code-block:: sh
+
+ lan-tun
+ lan-local
+ lan-dmz
+ tun-lan
+ tun-local
+ tun-dmz
+ local-lan
+ local-tun
+ local-dmz
+ dmz-lan
+ dmz-tun
+ dmz-local
+
+Notice, none go to WAN since WAN wouldn't have a v6 address on it.
+
+You would have to add a couple of rules on your wan-local ruleset to allow protocol 41 in.
+
+Something like:
+
+.. code-block:: sh
+
+ rule 400 {
+ action accept
+ destination {
+ address 172.16.10.1
+ }
+ log enable
+ protocol 41
+ source {
+ address ip.of.tunnel.broker
+ }
+ }
+
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