SMC Networks SMC8624/48T manual Access Control Lists

ACCESS CONTROL LISTS

•Control Bitmask – Decimal number representing the code bits to match.

The control bitmask is a decimal number (for an equivalent binary bit mask) that is applied to the control code. Enter a decimal number, where the equivalent binary bit “1” means to match a bit and “0” means to ignore a bit. The following bits may be specified:

-1 (fin) – Finish

-2 (syn) – Synchronize

-4 (rst) – Reset

-8 (psh) – Push

-16 (ack) – Acknowledgement

-32 (urg) – Urgent pointer

For example, use the code value and mask below to catch packets with the following flags set:

-SYN flag valid, use control-code 2, control bitmask 2

-Both SYN and ACK valid, use control-code 18, control bitmask 18

-SYN valid and ACK invalid, use control-code 2, control bitmask 18

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