Hi Tim,
okay, 1) I was not aware of outbound anti-spoofing. But in combination with anti-spoofing based on routing entries, isn't that a little bit like a chicken and egg problem? If I have a routing entry pointing to a specific gateway reachable via an outbound Interface, it automatically removes anti-spoofing blocks, so I could not possibly have outbound antispoofing. If I use manual anti-spoofing and groups and I have a discrepancy between routing table and anti-spoofing Group then yes, it could happen. So in my Case, the arrow only points down for inbound antispoofing.
But your suggestion to use fw log - was good, I tried that and isolated a particular case of an IP being dropped due to antispoofing and the logs are inconsistent. Sometimes it has the interface listed, sometimes it does not.
(Apologies .partially sanitized entries)
5:30:11 5 N/A 1 drop 192.168.95.57 < N/A LogId: <max_null>; ContextNum: <max_null>; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; HighLevelLogKey: 18446744073709551615; src: 172.26.17.203; dst: x.x.x.x; proto: tcp; message_info: Address spoofing; ProductName: VPN-1 & FireWall-1; svc: tls1.0; sport_svc: 57888; ProductFamily: Network;
5:30:14 5 N/A 1 drop 192.168.95.57 < N/A LogId: <max_null>; ContextNum: <max_null>; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; HighLevelLogKey: 18446744073709551615; src: 172.26.17.203; dst: x.x.x.x; proto: tcp; message_info: Address spoofing; ProductName: VPN-1 & FireWall-1; svc: tls1.0; sport_svc: 57888; ProductFamily: Network;
5:30:19 5 N/A 59 drop 192.168.95.57 > eth2-03 LogId: <max_null>; ContextNum: <max_null>; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; HighLevelLogKey: 18446744073709551615; src: 172.26.17.203; dst: x.x.x.x; proto: tcp; message_info: Address spoofing; ProductName: VPN-1 & FireWall-1; svc: tls1.0; sport_svc: 57889; ProductFamily: Network;
5:30:22 5 N/A 36 drop 192.168.95.57 > eth2-03 LogId: <max_null>; ContextNum: <max_null>; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; OriginSicName: CN=cp-rz2_fw1,O=rugell3.fp7ndk; HighLevelLogKey: 18446744073709551615; drop reason: Address spoofing; packet amount: 5; packets: <172.26.29.250,52392,x.x.x.x,443,6;eth2-03> <172.26.17.203,57889,x.x.x.x,443,6;eth2-03> <172.26.18.197,54354,x.x.x.x,443,6;eth2-03> <172.26.6.38,51828,x.x.x.x,443,6;eth2-03> <172.26.4.166,58941,x.x.x.x,443,6;eth2-03>; ProductName: VPN-1 & FireWall-1; ProductFamily: Network;
2. no we are only using tagged Interface. No PVID/Native Vlan being used anywhere. And per example 1) it must be coming from eth2-03 in the log entries because they are within a few seconds of each other. And yes, I agree, then it should list them with the physical Interface, instead of the subinterface/None.
3. no we are not using that