Thread: pcap filter for postgresql authorization

What is the pcap filter that would describe the 3 postgresql tcp (with md5)
connection packets separately?

The first one initializes the connection (form client to server)
The second one send the salt (from server to client)
The third one send the md5 password (form client to server)

I want the filter to return only these packages (separate filters for all of
3). Any help is greatly appreciated.

Cagil.