From 337dcdf07c51df2208da65aa9c5ab06a09d5cc3a Mon Sep 17 00:00:00 2001 From: Christian Poessinger Date: Tue, 28 May 2019 22:15:34 +0200 Subject: Appendix: create dedicated section in manual --- docs/examples/zone-policy.rst | 379 ------------------------------------------ 1 file changed, 379 deletions(-) delete mode 100644 docs/examples/zone-policy.rst (limited to 'docs/examples/zone-policy.rst') diff --git a/docs/examples/zone-policy.rst b/docs/examples/zone-policy.rst deleted file mode 100644 index d159d02d..00000000 --- a/docs/examples/zone-policy.rst +++ /dev/null @@ -1,379 +0,0 @@ -.. _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 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 - } - } - -- cgit v1.2.3