Spoof WAN packets

[Rubberducky]

Here we have a router with a few pc's connected.
To block certain pc's from internet access we use a packet-filter.
Every packet that is not LAN will be thrown away.
Is there a way to mask/spoof a WAN packet as a LAN packet so that the internet can still be accessed when the packet filter is enabled?
Someone once mentioned NetCat to me? Can this be done?

 

[havock]

Well the only way I can imagine someone "spoofing" WAN traffic as LAN traffic is to set up some sort of proxy connection where you connect to a computer that has internet access, then going from there to the internet.

This would require the computer w/ permission to have some type of proxy server running.

Or maybe I'm clueless.

EDIT: I dont condone you doing this. I only provide this info to aid in preventing it. <end CYA> dont flame me .

 

[Rubberducky]

I thought of that too, I have physical access to a pc that has constant internet access. Can I create a proxy server in VB?

 

[office politics]

the difference between a WAN and LAN packet is its destination address. You would need to change the destination address to effectively spoof the packet. The spoofed destination would have to meet the packet filter's criteria; presumably a destination address on the LAN. Your packet would never leave the LAN.

You'll need to think outside the box on this one. map the physical network structure and learn how the packet filter is setup.