Chapter 15 Unified Threat Management for FortiOS 5.0 : Custom Application & IPS Signatures : Custom signature keywords : Content keywords : byte_test
  
byte_test
Syntax: --byte_test <bytes_to_convert>, <operator>, <value>, <offset>[, relative] [, big] [, little] [, string] [, hex] [, dec] [, oct];
Description:
Use the byte_test keyword to compare a byte field against a specific value (with operator). This keyword is capable of testing binary values or converting representative byte strings to their binary equivalent and testing them. The available keyword options include:
<bytes_to_convert>: The number of bytes to compare.
<operator>: The operation to perform when comparing the value (<,>,=,!,&amp;).
<value>: The value to compare the converted value against.
<offset>: The number of bytes into the payload to start processing.
relative: Use an offset relative to last pattern match.
big: Process the data as big endian (default).
little: Process the data as little endian.string: The data is a string in the packet.
hex: The converted string data is represented in hexadecimal notation.
dec: The converted string data is represented in decimal notation.
oct: The converted string data is represented in octal notation.