I would like to intercept a packet generated by the router. The idea is that the router is sending a packet to initiate a L2TP tunnel and I would like to catch that packet.
The string into the packet could be the account name, like "john.smith" and I wanted to intercept the packets with that string.
I am looking for a L7-expression, but I did not find much regarding this topic except the already done filters.
Anybody can tell me the string or tell me where I can find more documents?
thank you in advance