Re: Tying a session to an IP address

[exon <exon () home se>]

Scovetta, Michael V wrote:
> ..."I'd say it doesn't do diddly squat to add to security, since it's 
> trivial to spoof ones address."
>
> Is that really true? Is it trivial to spoof an arbitrary, specific
> address? 

Yes. Ofcourse, the return traffic will go to the spoofed address, but 
the spoofed packets will still make it through.

> Can you make my traffic log think that you came from 
> 158.4.24.21? Or 127.0.0.1? 

Perhaps. What I can do is make the packet look like its coming from 
whatever address I want. What your machine believes is a different matter.

> I agree that within a subnet or behind
> a hacked router, sure, but at some point a router in the downline is
> going to say, "WTF! I don't know about the 158.4 subnet, screw that!"
You're assuming that routers care about a packets origin.

> Unless I totally misunderstand the issues at hand in spoofing IPs...
You might have.

> Mike

Andreas