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    Alias firewall block rule not blocked!

    Scheduled Pinned Locked Moved Firewalling
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    • M
      mrsunfire
      last edited by

      I did, I even rebootet the pfSense and the client. Nothing worked! I now deleted the Alias and created it new 1:1. Now it works! Very strange...

      Netgate 6100 MAX

      bmeeksB 1 Reply Last reply Reply Quote 0
      • bmeeksB
        bmeeks @mrsunfire
        last edited by

        @mrsunfire said in Alias firewall block rule not blocked!:

        I did, I even rebootet the pfSense and the client. Nothing worked! I now deleted the Alias and created it new 1:1. Now it works! Very strange...

        Could you have had a space (like a trailing space, perhaps) in your alias? I have not looked at the pfSense PHP code for the Alias page to see if it scrubs input for trailing spaces. I have been the victim of that trailing space thing in other situations not involving pfSense (like a Windows filename, for example). This problem is very hard to detect because a trailing space is going to be invisible on the screen. Sometimes you can tell it's there by going to the end of a line and then you notice an extra space, but then sometimes that trick does not work. The fact deleting and then recreating the alias fixed the problem points to having a hidden character in there maybe.

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        • M
          mrsunfire
          last edited by mrsunfire

          Well the Alias „worked“. One IP and the FQDN worked. Only the other IP not. There was nothing special in it and I did the same again and now it works.

          Netgate 6100 MAX

          bmeeksB 1 Reply Last reply Reply Quote 0
          • bmeeksB
            bmeeks @mrsunfire
            last edited by

            '192.168.1.17"@mrsunfire said in Alias firewall block rule not blocked!:

            Well the Alias „worked“. One IP and the FQDN worked. Only the other IP not. There was nothing special in it and I did the same again and now it works.

            Unless I misunderstood what you wrote and posted originally, you created an alias called NoWAN and put three entries in it. One of those was a hostname "drucker" and the other two were actual IP addresses. The host name would have been internally converted to an IP by the pfSense code. What I am saying is maybe when you put the 192.168.1.17 IP address in you inadvertently had a trailing space on the end when you typed it into the text box on the alias creation page. So instead of just "192.168.1.17" you actually had "192.168.1.17 " (notice the extra space after the 17). To a computer "192.168.1.17 " is not the same as "192.168.1.17". You would not have been able to see this trailing space on the screen. When you deleted the alias the trailing space entry would have also been removed. When you created it again the trailing space was not there and so things worked as expected.

            This is just a theory based on having this type of event happen to me in the past on other platforms. It's easy to typo a trailing space on something and then you can't see it's there to fix it. Some software will automatically scrub user-typed input to remove trailing spaces, but not always. I need to check the pfSense code to see if it does that when letting the user create alias entries.

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by

              If you put a trailing space on it - pfsense balks at you
              space.png

              An intelligent man is sometimes forced to be drunk to spend time with his fools
              If you get confused: Listen to the Music Play
              Please don't Chat/PM me for help, unless mod related
              SG-4860 24.11 | Lab VMs 2.8, 24.11

              bmeeksB 1 Reply Last reply Reply Quote 1
              • bmeeksB
                bmeeks @johnpoz
                last edited by

                @johnpoz said in Alias firewall block rule not blocked!:

                If you put a trailing space on it - pfsense balks at you
                space.png

                Thanks for the quick test! So my theory is not valid. pfSense apparently does a good job of input scrubbing.

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  Without seeing is full rule set, floating even and his current states its not really possible to understand what the issue might of been.

                  Its quite possible this .17 had a state open to internet he was testing with.. Which is why it was working when he first put in the rule.. Or for that matter maybe the .17 uses proxy..

                  KOM really hit it on the nose - and it causes many users misunderstanding of how rules and when they get applied..

                  An intelligent man is sometimes forced to be drunk to spend time with his fools
                  If you get confused: Listen to the Music Play
                  Please don't Chat/PM me for help, unless mod related
                  SG-4860 24.11 | Lab VMs 2.8, 24.11

                  bmeeksB 1 Reply Last reply Reply Quote 0
                  • bmeeksB
                    bmeeks @johnpoz
                    last edited by

                    @johnpoz said in Alias firewall block rule not blocked!:

                    Without seeing is full rule set, floating even and his current states its not really possible to understand what the issue might of been.

                    Its quite possible this .17 had a state open to internet he was testing with.. Which is why it was working when he first put in the rule.. Or for that matter maybe the .17 uses proxy..

                    KOM really hit it on the nose - and it causes many users misunderstanding of how rules and when they get applied..

                    I agree it could have been an active state, but it is puzzling still as the state should still have been in place when he added that independent rule with just the IP and not the alias. So I would expect that extra rule to not block either. Of course, we don't know the full extent of what the rules in force were at the time.

                    That trailing space thing is just etched in my brain now because I've been victimized several times by it over the years. Most recently about two months ago on my wife's Windows 10 machine where she complained about not being able to delete a directory. Turns out, after much investigation, it was the trailing space thing again.

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                    • M
                      mrsunfire
                      last edited by

                      There was no active state. I checked it multiple times with pfTop. Even after reboot the .17 got wide open access to internet. The Alias had no problem, no extra space or something else. I now created it exactly the same and now also the .17 gets blocked.

                      I only have 1 Floating rule for ICMPv6, nothing special on LAN. The Alias always is on top of course. There is no proxy setup.

                      Netgate 6100 MAX

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                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        If the IP address was in the alias and there was no active state it would have been blocked.

                        If something else was the result then there was a reason for it. Finding that reason is the trick.

                        When you have an active state you can use pfctl to find which rule passed the connection should you desire to dig that deep. If I had traffic I thought should be blocked that wasn't, I would want to know why.

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                        • M
                          mrsunfire
                          last edited by

                          There should be no active state after a reboot. I now did the same as before and now the IP gets blocked. If I could simulate that error again, I would do that.

                          Netgate 6100 MAX

                          1 Reply Last reply Reply Quote 0
                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            It was user error. You did not find a bug in pf that passed blocked traffic.

                            Chattanooga, Tennessee, USA
                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                            • M
                              mrsunfire
                              last edited by

                              Then how do you explain from my first screen that the alias is on top and the .17 IP is on 3th line of rules. But that one blocks the traffic and the alias did not?

                              Netgate 6100 MAX

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                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by

                                User error. Not understanding what you are looking at. State established before the rule was in place. Some other rule passing the traffic.

                                Chattanooga, Tennessee, USA
                                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                • M
                                  mrsunfire
                                  last edited by

                                  So the state stays established even after a reboot? I can't believe that...

                                  Netgate 6100 MAX

                                  1 Reply Last reply Reply Quote 0
                                  • DerelictD
                                    Derelict LAYER 8 Netgate
                                    last edited by

                                    No. The state was re-established after you rebooted because a firewall rule passed the traffic.

                                    Chattanooga, Tennessee, USA
                                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                    • M
                                      mrsunfire
                                      last edited by

                                      I restored the firewall rules to an earlier date and rebooted the machine. The alias is still the same and now the .17 again gets access. How to find out what rule is the problem?pf1.jpg

                                      Netgate 6100 MAX

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                                      • DerelictD
                                        Derelict LAYER 8 Netgate
                                        last edited by

                                        pfctl -vvss | grep -A3 192.168.1.17

                                        Find the state you think should not be there out of that. Post it.

                                        Chattanooga, Tennessee, USA
                                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                        • M
                                          mrsunfire
                                          last edited by

                                          @Derelict said in Alias firewall block rule not blocked!:

                                          pfctl -vvss | grep -A3 192.168.1.17

                                          igb4 udp 192.168.1.1:53 <- 192.168.1.17:50872       NO_TRAFFIC:SINGLE
                                             age 00:00:55, expires in 00:00:05, 1:0 pkts, 56:0 bytes, rule 164
                                             id: 010000005cd28985 creatorid: 3dddfb2a
                                          igb4 udp 192.168.1.255:32414 <- 192.168.1.10:55418       NO_TRAFFIC:SINGLE
                                          --
                                          igb4 udp 192.168.1.1:53 <- 192.168.1.17:43906       NO_TRAFFIC:SINGLE
                                             age 00:00:55, expires in 00:00:05, 1:0 pkts, 59:0 bytes, rule 164
                                             id: 010000005cd28988 creatorid: 3dddfb2a
                                          igb5 ipv6-icmp ff02::1[192] <- fe80::201:5cff:fe6b:e046[192]       NO_TRAFFIC:NO_TRAFFIC
                                          --
                                          igb4 udp 114.55.218.176:32100 <- 192.168.1.17:27288       NO_TRAFFIC:SINGLE
                                             age 00:00:48, expires in 00:00:12, 1:0 pkts, 32:0 bytes, rule 178
                                             id: 010000005cd28a38 creatorid: 485eb46e
                                          igb4 udp 47.91.90.222:32100 <- 192.168.1.17:27288       NO_TRAFFIC:SINGLE
                                             age 00:00:48, expires in 00:00:12, 1:0 pkts, 32:0 bytes, rule 178
                                             id: 010000005cd28a39 creatorid: 485eb46e
                                          igb4 udp 192.168.1.1:161 <- 192.168.1.10:56756       MULTIPLE:MULTIPLE
                                          --
                                          igb4 udp 107.20.134.235:32100 <- 192.168.1.17:27288       NO_TRAFFIC:SINGLE
                                             age 00:00:48, expires in 00:00:12, 1:0 pkts, 32:0 bytes, rule 178
                                             id: 000000005cd28acc creatorid: 485eb46e
                                          igb4.300 udp 8.8.8.8:53 <- 10.0.2.2:45009       NO_TRAFFIC:SINGLE
                                          --
                                          igb4 udp 192.168.1.1:53 <- 192.168.1.17:51499       SINGLE:MULTIPLE
                                             age 00:00:33, expires in 00:00:00, 1:1 pkts, 56:72 bytes, rule 181
                                             id: 000000005cd28c1a creatorid: b13ad8d2
                                          igb5 udp 2a02:8071:800:0:527:2af9:a20f:552a[41679] -> 2001:8d8:fe:53:0:d9a0:52c2:100[53]       MULTIPLE:SINGLE
                                          --
                                          igb4 udp 107.20.134.235:32100 <- 192.168.1.17:25029       SINGLE:MULTIPLE
                                             age 00:00:33, expires in 00:00:00, 1:1 pkts, 32:48 bytes, rule 181
                                             id: 000000005cd28c1b creatorid: b13ad8d2
                                          igb5 udp xxx:64148 -> 217.160.83.194:53       MULTIPLE:SINGLE
                                          --
                                          igb5 udp xxx:57526 (192.168.1.17:25029) -> 107.20.134.235:32100       MULTIPLE:SINGLE
                                             age 00:00:33, expires in 00:00:00, 1:1 pkts, 32:48 bytes, rule 141
                                             id: 000000005cd28c1c creatorid: b13ad8d2
                                          igb5 udp 2a02:8071:800:0:527:2af9:a20f:552a[45428] -> 2001:503:e239::3:2[53]       MULTIPLE:SINGLE
                                          --
                                          igb4 udp 192.168.1.1:53 <- 192.168.1.17:35486       SINGLE:MULTIPLE
                                             age 00:00:33, expires in 00:00:00, 1:1 pkts, 61:77 bytes, rule 181
                                             id: 010000005cd28c21 creatorid: b13ad8d2
                                          igb4 udp 107.20.134.235:32100 <- 192.168.1.18:10092       MULTIPLE:MULTIPLE
                                          --
                                          igb4 udp 114.55.218.176:32100 <- 192.168.1.17:25029       NO_TRAFFIC:SINGLE
                                             age 00:00:33, expires in 00:00:27, 1:0 pkts, 32:0 bytes, rule 181
                                             id: 010000005cd28c22 creatorid: b13ad8d2
                                          igb5 udp xxx:41955 (192.168.1.18:10092) -> 107.20.134.235:32100       MULTIPLE:MULTIPLE
                                          --
                                          igb5 udp xxx:10147 (192.168.1.17:25029) -> 114.55.218.176:32100       SINGLE:NO_TRAFFIC
                                             age 00:00:33, expires in 00:00:27, 1:0 pkts, 32:0 bytes, rule 141
                                             id: 010000005cd28c23 creatorid: b13ad8d2
                                          igb4 udp 2a02:8071:889:c500:4262:31ff:fe07:2bdc[53] <- 2a02:8071:889:c500:f525:878c:30fa:1bb5[50603]       SINGLE:MULTIPLE
                                          --
                                          igb4 udp 47.91.90.222:32100 <- 192.168.1.17:25029       SINGLE:MULTIPLE
                                             age 00:00:33, expires in 00:00:00, 1:1 pkts, 32:48 bytes, rule 181
                                             id: 010000005cd28c24 creatorid: b13ad8d2
                                          igb4 udp 192.168.1.1:53 <- 192.168.1.122:53655       SINGLE:MULTIPLE
                                          --
                                          igb5 udp xxx:51011 (192.168.1.17:25029) -> 47.91.90.222:32100       MULTIPLE:SINGLE
                                             age 00:00:33, expires in 00:00:00, 1:1 pkts, 32:48 bytes, rule 141
                                             id: 010000005cd28c25 creatorid: b13ad8d2
                                          igb4 udp 114.55.218.176:32100 <- 192.168.1.18:21763       NO_TRAFFIC:SINGLE
                                          

                                          Netgate 6100 MAX

                                          DerelictD 1 Reply Last reply Reply Quote 0
                                          • DerelictD
                                            Derelict LAYER 8 Netgate @mrsunfire
                                            last edited by

                                            @mrsunfire OK, help me out. Which state should not be there?

                                            Chattanooga, Tennessee, USA
                                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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