3Com REMOTE ACCESS SYSTEM 1500, Management Manual

Page: 225 / 300

Creating Filters
223
Generic Filter Rules
Generic filter rules are similar in format to protocol filter rules. The
following shows the rule syntax. The following is the rule syntax:
<line #> <verb> <keyword> <operator> origin = <DATA | FRAME>/
offset = <value>/length = <value>/mask = <hexadecimal value>/
value = <hexadecimal value>;
Table 59 describes each field used in the rule syntax.
Table 59 Generic Filter Rules
For example, a generic filter rule might look like the following:
010 ACCEPT generic => origin = data/offset = 22/length = 6/
mask = 0xFFFFFFFFFFFF/value = 0x0800096f39c8;
Field Description
line #
Each rule must have a unique line number (
1-999
). You must arrange
rules in increasing order.
verb
This field can be one of the following:
■
ACCEPT
—allow packet access if the condition is met
■
REJECT
— do not allow packet access if the condition is met
■
AND
— logically use the AND condition with condition of the next
rule to determine if packet is accepted or rejected. Both defined
conditions must be met.
IMPORTANT:
No more than 15 consecutive
AND rules are permitted.
keyword
The keywords for a generic filter rule is always
GENERIC
.
operator
The operator for a generic filter rule is always: =>
origin
Can be either
FRAME
or
DATA
offset
This is the number of bytes offset from the origin.
length
This is the number of bytes to compare and mask.
mask
This is the bit mask, in hexadecimal format, for logical and packet
content. (
00
or
FF
)
value
This value, in hexadecimal format, is used to compare with contents of
masked packet