ZyWALL 2 and ZyWALL 2WE

19.2.3 Configuring a Generic Filter Rule

This section shows you how to configure a generic filter rule. The purpose of generic rules is to allow you to filter non-IP packets. For IP, it is generally easier to use the IP rules directly.

For generic rules, the ZyWALL treats a packet as a byte stream as opposed to an IP or IPX packet. You specify the portion of the packet to check with the Offset (from 0) and the Length fields, both in bytes. The ZyWALL applies the Mask (bit-wise ANDing) to the data portion before comparing the result against the Value to determine a match. The Mask and Value are specified in hexadecimal numbers. Note that it takes two hexadecimal digits to represent a byte, so if the length is 4, the value in either field will take 8 digits, for example, FFFFFFFF.

To configure a generic rule, select Generic Filter Rule in the Filter Type field in menu 21.1.4.1 and press [ENTER] to open Generic Filter Rule, as shown below.

Menu 21.1.4.1 - Generic Filter Rule

Filter #: 4,1

Filter Type= Generic Filter Rule

Active= No

 

Offset= 0

 

Length= 0

 

Mask= N/A

 

Value= N/A

Log= None

More= No

Action Matched= Check Next Rule

Action Not Matched= Check Next Rule

Press ENTER to Confirm or ESC to Cancel:

Press Space Bar to Toggle.

Figure 19-7 Menu 21.1.4.1: Generic Filter Rule

The following table describes the fields in the Generic Filter Rule menu.

Filter Configuration

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