Chapter 15 Unified Threat Management for FortiOS 5.0 : Custom Application & IPS Signatures : Custom signature keywords : Content keywords : context
  
context
Syntax: --context {uri | header | body | host};
Description:
Specify the protocol field to look for the pattern. If context is not specified for a pattern, the FortiGate unit searches for the pattern anywhere in the packet buffer.
The available context variables are:
uri: Search for the pattern in the HTTP URI line.
header: Search for the pattern in HTTP header lines or SMTP/POP3/SMTP control messages.
body: Search for the pattern in HTTP body or SMTP/POP3/SMTP email body.
host: Search for the pattern in HTTP HOST line.