itype

The itype rule option is used to check that a packet's ICMP type is less than, greater than, equal to, not equal to, less than or equal to, or greater than or equal to a specified integer value. This rule option can also check that an ICMP type is between a range of numbers, using the <> range operator for an exclusive range check or the <=> for an inclusive one.

Format:

Single value comparison:

itype:[<|>|=|!|<=|>=]itype;

Range comparison:

itype:itype_min{<>|<=>}itype_max;

Examples:

# Check for an ICMP type greater than 30
itype:>30;