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    Firewall Rule Help

    Scheduled Pinned Locked Moved Firewalling
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    • V
      viragomann
      last edited by

      Firwall rules are applied on the incoming interface. So a rule with source = LAN2net on LAN1 interface will not have any effect.

      Your rule set may look like this way:

      LAN1:

      
                ID       Proto       Source     Port     Destination       Port       Gateway        Queue       Schedule        Description
      Pass               *           *          *        LAN1 Address      80 9022    *              *                           Anti-Lockout Rule
      Pass               IPv4*       LAN1net    *        192.168.20.4      *          *              none                        DVR
      Block              IPv4*       *          *        RFC1918           *          *              none                        Block internal networks
      Pass               IPv4*       LAN1net    *        *                 *          *              none                        Default allow LAN1 to any rule
      
      

      LAN2:

      
                ID       Proto       Source     Port     Destination       Port       Gateway        Queue       Schedule        Description
      Block              IPv4*       *          *        RFC1918           *          *              none                        Block internal networks
      Pass               IPv4*       LAN2net    *        *                 *          *              none                        allow Internet
      
      

      RFC1918 is an alias which includes all RFC 1918 networks. This will still be save if you add an additional private network in the future.

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      • S
        Stewart
        last edited by

        Interesting.  I didn't know about using RFC1918 as an alias to block internal networks.  I tried just using * but it didn't do what I wanted.  I'll give it a shot.

        Edit:  Using RFC1918 results in an error of "RFC1918 is not a valid destination IP address or alias."  Is it an alias I need to create?

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        • KOMK
          KOM
          last edited by

          Make your own similar alias using:

          RFC1918
          10.0.0.0/8
          172.16.0.0/12
          192.168.0.0/16
          127.0.0.0/8

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          • S
            Stewart
            last edited by

            @KOM:

            Make your own similar alias using:

            RFC1918
            10.0.0.0/8
            172.16.0.0/12
            192.168.0.0/16
            127.0.0.0/8

            Thanks.  I'd created an alias with just the 192.168.0.0/16 but you're right that it's a good idea to have them all in there.  Thanks!

            Edit:  Wouldn't we then be saying to block even the subnet that it is on?  You're saying to block anything from that subnet going to a private IP of any subnet (including its own) then block it.  Would I then need a rule that says to allow from the LAN2 Net to LAN2 Net above the RFC1918 rule on the LAN2 Interface?  Like:

            
            	ID 	Proto 	Source 		Port 	Destination 	Port 	Gateway 	Queue 	Schedule 	Description
            Pass	  	IPv4*	LAN2net		* 	LAN2Net 		* 	* 		none 	  	Allow subnet to communicate on port
            
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            • KOMK
              KOM
              last edited by

              Inter-LAN traffic doesn't hit the gateway, so pfSense would not be involved in those comms at all.  pfSense and the pf firewall only come into play when the traffic is leaving the network for another.

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              • S
                Stewart
                last edited by

                @KOM:

                Inter-LAN traffic doesn't hit the gateway, so pfSense would not be involved in those comms at all.  pfSense and the pf firewall only come into play when the traffic is leaving the network for another.

                OK.  So it only affects if it goes across from one interface to another.  I thought the inspection happened as the packet was received.

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                • KOMK
                  KOM
                  last edited by

                  Hosts on the same subnet can find each other and talk to each other without needing a gateway.  The packets are routed directly unless the destination is outside the scope of the network (subnet mask), at which point they get sent to the default gateway instead.

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                  • S
                    Stewart
                    last edited by

                    @KOM:

                    Hosts on the same subnet can find each other and talk to each other without needing a gateway.  The packets are routed directly unless the destination is outside the scope of the network (subnet mask), at which point they get sent to the default gateway instead.

                    What about logging into the router?  If I'm at 192.168.20.2 and the Router is 192.168.20.1 and I'm blocking all private traffic, wouldn't that request to connect to the router be rejected?

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                    • V
                      viragomann
                      last edited by

                      That is what the "Anti-lockout rule" on LAN interface is for. As you have activated "Anti-lockout" in the System > Advanced > Admin access this rule is set and you can't delete it from the rule set.

                      So logging in to the Web-GUI is only possible from LAN network. If you want to restrict the access to only one or a few source IPs you have to create your own anti-lockout rule and remove the check from Anti-lockout.

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                      • S
                        Stewart
                        last edited by

                        Got it.  Thanks.  Looking back at the things I was doing wrong, it seems I was setting the right rules on the wrong interfaces or specifying the wrong interface source.  Thanks for all the help.

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