Socket - Fiirewall

[Salvatore]

Thank you for your quick response,

I'm totally agreee with you concerning the fact of developping a real 
firewall.
In fact, what I would like to do is using a program
like windump or tcpdump, dump the data in a file that I could parse
with Python, and blocking the port I'd consider as intrusive.

Salvatore





Rene Pijlman wrote:
> Salvatore:
> 
>>I would like to create a little firewall in Python,
>>Does anybody know how to block a port like a FireWall ?
> 
> 
> That's the easy part.
> 
>     receive(packet)
>     if packet.destination_port == 80:
>         send(packet)
>     else:
>         pass
>     # :-)
> 
> Firewalls are typically implemented in a primitive
> high-performance language (C) at the TCP/IP routing layer in the
> OS kernel. I don't think this is a good application for an
> interpreted high level scripting language like Python, that
> typically resides ~3 layers higher in the protocol stack.
>