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    [SOLVED] Do not log TCP packets with flags TCP:RA / TCP:PA etc.

    Scheduled Pinned Locked Moved Firewalling
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    • M
      mcury Rebel Alliance @johnpoz
      last edited by mcury

      @johnpoz said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

      10 years - just a baby then

      Yeap, I started with Cisco routers and switches and around 15 years ago, and around 10 years ago it was just firewalls, Cisco ASA, Fortigate, Checkpoint, Palo Alto and Sonicwall, never looked back but we never forget the routing stuff =)

      @johnpoz said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

      that is just non Syn traffic looks like.

      In the pic above, I was just filtering just TCP, but excluding SYN.. let me include UDP in it. Here it goes:

      095ff27d-9cb7-43c2-9b32-8d75490dd946-image.png

      @johnpoz said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

      What about UDP noise? You doing any filtering by source IP that your not logging?

      Edit: Logging all TCP but TCP:S and all UDP traffic that hit both WANs, disabled packets that are blocked by the implicit default block rule.

      dead on arrival, nowhere to be found.

      johnpozJ 1 Reply Last reply Reply Quote 0
      • johnpozJ
        johnpoz LAYER 8 Global Moderator @mcury
        last edited by

        @mcury said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

        and all UDP traffic that hit both WANs

        You might want to limit that to interesting ports if your goal is trim down the amount of noise your logging. My interesting ports is a pretty long list, but it does reduce some of the noise not logging every port ;)

        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

        M 1 Reply Last reply Reply Quote 1
        • M
          mcury Rebel Alliance @johnpoz
          last edited by

          @johnpoz said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

          You might want to limit that to interesting ports if your goal is trim down the amount of noise your logging. My interesting ports is a pretty long list, but it does reduce some of the noise not logging every port ;)

          I'll start preparing that list now.. =)

          dead on arrival, nowhere to be found.

          johnpozJ 1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator @mcury
            last edited by johnpoz

            @mcury here is my list.. It prob way longer than need/should be but I had does some looking to what ports to put in there while back..

            2:3 Entry added Thu, 17 Oct 2019 06:17:40 -0500
7 Entry added Thu, 17 Oct 2019 06:17:40 -0500
9 Entry added Thu, 17 Oct 2019 06:17:40 -0500
13 Entry added Thu, 17 Oct 2019 06:17:40 -0500
17 Entry added Thu, 17 Oct 2019 06:17:40 -0500
19:23 Entry added Thu, 17 Oct 2019 06:17:40 -0500
37:38 Entry added Thu, 17 Oct 2019 06:17:40 -0500
42 Entry added Thu, 17 Oct 2019 06:17:40 -0500
49 Entry added Thu, 17 Oct 2019 06:17:40 -0500
67:69 Entry added Thu, 17 Oct 2019 06:17:40 -0500
80 Entry added Thu, 17 Oct 2019 06:17:40 -0500
88 Entry added Thu, 17 Oct 2019 06:17:40 -0500
111:113 Entry added Thu, 17 Oct 2019 06:17:40 -0500
120 Entry added Thu, 17 Oct 2019 06:17:40 -0500
135:139 Entry added Thu, 17 Oct 2019 06:17:40 -0500
158 Entry added Thu, 17 Oct 2019 06:17:40 -0500
161:162 Entry added Thu, 17 Oct 2019 06:17:40 -0500
177 Entry added Thu, 17 Oct 2019 06:17:40 -0500
192 Entry added Thu, 17 Oct 2019 06:17:40 -0500
199 Entry added Thu, 17 Oct 2019 06:17:40 -0500
207 Entry added Thu, 17 Oct 2019 06:17:40 -0500
217 Entry added Thu, 17 Oct 2019 06:17:40 -0500
363 Entry added Thu, 17 Oct 2019 06:17:40 -0500
389 Entry added Thu, 17 Oct 2019 06:17:40 -0500
402 Entry added Thu, 17 Oct 2019 06:17:40 -0500
407 Entry added Thu, 17 Oct 2019 06:17:40 -0500
427 Entry added Thu, 17 Oct 2019 06:17:40 -0500
434 Entry added Thu, 17 Oct 2019 06:17:40 -0500
443 Entry added Thu, 17 Oct 2019 06:17:40 -0500
445 Entry added Thu, 17 Oct 2019 06:17:40 -0500
464 Entry added Thu, 17 Oct 2019 06:17:40 -0500
497 Entry added Thu, 17 Oct 2019 06:17:40 -0500
500 Entry added Thu, 17 Oct 2019 06:17:40 -0500
502 Entry added Thu, 17 Oct 2019 06:17:40 -0500
512:515 Entry added Thu, 17 Oct 2019 06:17:40 -0500
517:518 Entry added Thu, 17 Oct 2019 06:17:40 -0500
520 Entry added Thu, 17 Oct 2019 06:17:40 -0500
539 Entry added Thu, 17 Oct 2019 06:17:40 -0500
559 Entry added Thu, 17 Oct 2019 06:17:40 -0500
593 Entry added Thu, 17 Oct 2019 06:17:40 -0500
623 Entry added Thu, 17 Oct 2019 06:17:40 -0500
626 Entry added Thu, 17 Oct 2019 06:17:40 -0500
631 Entry added Thu, 17 Oct 2019 06:17:40 -0500
639 Entry added Thu, 17 Oct 2019 06:17:40 -0500
643 Entry added Thu, 17 Oct 2019 06:17:40 -0500
657 Entry added Thu, 17 Oct 2019 06:17:40 -0500
664 Entry added Thu, 17 Oct 2019 06:17:40 -0500
682:689 Entry added Thu, 17 Oct 2019 06:17:40 -0500
764 Entry added Thu, 17 Oct 2019 06:17:40 -0500
767 Entry added Thu, 17 Oct 2019 06:17:40 -0500
772:776 Entry added Thu, 17 Oct 2019 06:17:40 -0500
780:782 Entry added Thu, 17 Oct 2019 06:17:40 -0500
786 Entry added Thu, 17 Oct 2019 06:17:40 -0500
789 Entry added Thu, 17 Oct 2019 06:17:40 -0500
800 Entry added Thu, 17 Oct 2019 06:17:40 -0500
814 Entry added Thu, 17 Oct 2019 06:17:40 -0500
826 Entry added Thu, 17 Oct 2019 06:17:40 -0500
829 Entry added Thu, 17 Oct 2019 06:17:40 -0500
838 Entry added Thu, 17 Oct 2019 06:17:40 -0500
902:903 Entry added Thu, 17 Oct 2019 06:17:40 -0500
944 Entry added Thu, 17 Oct 2019 06:17:40 -0500
959 Entry added Thu, 17 Oct 2019 06:17:40 -0500
965 Entry added Thu, 17 Oct 2019 06:17:40 -0500
983 Entry added Thu, 17 Oct 2019 06:17:40 -0500
989:990 Entry added Thu, 17 Oct 2019 06:17:40 -0500
996:1001 Entry added Thu, 17 Oct 2019 06:17:40 -0500
1007:1008 Entry added Thu, 17 Oct 2019 06:17:40 -0500
1012:1014 Entry added Thu, 17 Oct 2019 06:17:40 -0500
1019:1051 Entry added Thu, 17 Oct 2019 06:17:40 -0500
1053:1060 Entry added Thu, 17 Oct 2019 06:17:40 -0500
53 Entry added Thu, 17 Oct 2019 12:07:49 -0500
123 Entry added Sat, 11 Apr 2020 02:33:04 -0500
33434 Odd port from pfsense forums

            Wow from 2019, man time flies.. Doesn't seem like that long ago that I did that ;)

            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

            M 1 Reply Last reply Reply Quote 1
            • m0ursM
              m0urs @bmeeks
              last edited by m0urs

              @bmeeks
              Unfortunately it seems not to work that way. I still get packets logged with these flags set:

              c34ff848-a91c-4dac-b2c0-93681a5621eb-image.png

              Do not get confused, I named my self created rule "Default blocking rule", but the ID is my own rule and not the pfSense default rule.

              Here is the rule I created:

              7bf8dc21-035c-46ff-9776-31373ad24ce9-image.png

              93835a43-fd4b-44a4-9cb9-36b3b01363be-image.png

              What am I doing wrong?

              M 1 Reply Last reply Reply Quote 0
              • M
                mcury Rebel Alliance @johnpoz
                last edited by mcury

                @johnpoz Wol, that is indeed a long list, I was thinking about ports:

                7 WOL common used
9 WOL default
53 DNS
67:68 DHCP
80 QUIC
88 Kerberos
123 NTP
443 QUIC
500 IPsec
514 Syslog
1194:1198 Common OpenVPN ports..
4500 NAT-T

                dead on arrival, nowhere to be found.

                johnpozJ 1 Reply Last reply Reply Quote 0
                • M
                  mcury Rebel Alliance @m0urs
                  last edited by

                  @m0urs said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

                  What am I doing wrong?

                  Did you disable this ?

                  24112498-ef2f-4826-9425-2ac6a8912499-image.png

                  dead on arrival, nowhere to be found.

                  m0ursM 1 Reply Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @mcury
                    last edited by johnpoz

                    @mcury yeah its a bit long.. I went a bit overboard when was looking into ports that might be good to log.. I could prob trim it down.. But I really don't see much udp traffic even with that long list.

                    Yeah default deny logging is off

                    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

                    1 Reply Last reply Reply Quote 0
                    • m0ursM
                      m0urs @mcury
                      last edited by

                      @mcury said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

                      Did you disable this ?

                      Yes.

                      As I said: The logging comes from my own created rule and not from the pfSense default blocking rule.

                      M 1 Reply Last reply Reply Quote 0
                      • M
                        mcury Rebel Alliance @m0urs
                        last edited by

                        @m0urs said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

                        The logging comes from my own created rule and not from the pfSense default blocking rule.

                        I'm trying to replicate this here, but now filtering TCP:S only, in my LAN networks.

                        dead on arrival, nowhere to be found.

                        M 1 Reply Last reply Reply Quote 0
                        • M
                          mcury Rebel Alliance @mcury
                          last edited by

                          Are you using that "Invert match" option for source or destination in that rule ? So far, I'm unable to replicate this behavior here but I'm not using those options.

                          dead on arrival, nowhere to be found.

                          m0ursM 2 Replies Last reply Reply Quote 0
                          • m0ursM
                            m0urs @mcury
                            last edited by

                            @mcury No, I do not use "Invert Match". That is my definition, together with that TCP Flags option mentioned above:

                            5e3f4c21-62e3-46e7-a1c4-963fee7d2124-image.png

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                            • m0ursM
                              m0urs @mcury
                              last edited by

                              @mcury ah, maybe this does not work if protocol set to "Any"? I will try with Protocol set to "TCP" ...

                              m0ursM 1 Reply Last reply Reply Quote 0
                              • m0ursM
                                m0urs @m0urs
                                last edited by

                                @mcury

                                No, unfortunately that did not change anything. These kind of packets are still logged by that rule:

                                70421b24-d1ae-41af-bf94-6343b09cd5ad-image.png

                                You you explain me a bit more, what how this "TCP flag" setting is working? I still did not get it. What exactly is meant by "set" and "out of"?

                                M 1 Reply Last reply Reply Quote 0
                                • M
                                  mcury Rebel Alliance @m0urs
                                  last edited by

                                  @m0urs said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

                                  What exactly is meant by "set" and "out of"?

                                  https://docs.netgate.com/pfsense/en/latest/firewall/configure.html#tcp-flags

                                  dead on arrival, nowhere to be found.

                                  m0ursM 1 Reply Last reply Reply Quote 0
                                  • m0ursM
                                    m0urs @mcury
                                    last edited by m0urs

                                    @mcury

                                    "By default, new pass rules for TCP only check for the TCP SYN flag to be set, out of a possible set of SYN and ACK."

                                    Hm, so I would say that I just need to create a normal rule without any options enabled in "TCP flag"? In this case I do get a logging entry if there is something blocked with SYNC flag and no more logging entries for all the other packtes?

                                    That would be what I wanted?

                                    Update: It says "new PASS rules", but I have a REJECT rule?

                                    M 1 Reply Last reply Reply Quote 0
                                    • M
                                      mcury Rebel Alliance @m0urs
                                      last edited by

                                      @m0urs said in Do not log TCP packets with flags TCP:RA / TCP:PA etc.:

                                      @mcury

                                      "By default, new pass rules for TCP only check for the TCP SYN flag to be set, out of a possible set of SYN and ACK."

                                      Hm, so I would say that I just need to create a normal rule without any options enabled in "TCP flag"? In this case I do get a logging entry if there is something blocked with SYNC flag and no more logging entries for all the other packtes?

                                      That would be what I wanted?

                                      Yes, try that and report back.
                                      Other option would be to create a new rule below that one, and set flags to all but SYN, and set to no log.

                                      dead on arrival, nowhere to be found.

                                      m0ursM 1 Reply Last reply Reply Quote 0
                                      • m0ursM
                                        m0urs @mcury
                                        last edited by

                                        @mcury I had a look into the Packet Filter rules generated by pfSense.

                                        Could it be that these options are only used for PASS rules but not for BLOCK rules?

                                        Here is the output for that rule either with PASS:

                                        [2.7.2-RELEASE][root@router02.urs.lan]/root: pfctl -vvsr | grep "33276"

@177 pass in log quick on igb2.20 inet all flags S/SA keep state label "USER_RULE" label "id:1704133276" ridentifier 1704133276

                                        and with BLOCK:

                                        [2.7.2-RELEASE][root@router02.urs.lan]/root: pfctl -vvsr | grep "33276"

@177 block drop in log quick on igb2.20 inet all label "USER_RULE" label "id:1704133276" ridentifier 1704133276
                                        johnpozJ 1 Reply Last reply Reply Quote 0
                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator @m0urs
                                          last edited by

                                          @m0urs not sure what your looking at exactly - but those rules block and only syn..

                                          block.jpg

                                          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

                                          m0ursM 2 Replies Last reply Reply Quote 0
                                          • m0ursM
                                            m0urs @johnpoz
                                            last edited by

                                            @johnpoz

                                            Notice the "flag s/s" in your blocking rule?

                                            Compare it with my blocking rule above, which is missing that ...

                                            So I guess that is the reason, why it is not working for me.

                                            If I change the rule to "PASS" then the "flag s/s" is added. If I change it back to "BLOCK", it is missing!?

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