Chapter 15 Unified Threat Management for FortiOS 5.0 : Custom Application & IPS Signatures : Custom signature keywords : IP header keywords
  
IP header keywords
dst_addr
Syntax: --dst_addr [!]<ipv4>;
Description:
Use the dst_addr keyword to search for the destination IP address. To have the FortiGate search for a packet that does not contain the specified address, add an exclamation mark (!) before the IP address. You can define up to 28 IP addresses or CIDR blocks. Enclose the comma separated list in square brackets.
Example: dst_addr [172.20.0.0/16, 10.1.0.0/16,192.168.0.0/16]