Re: TCP-Programming: Port connects to itself? Why is this possible?

> I just noticed that it is possible to open a TCP-socket and connect it to
> itself ... I don't see how / why this makes sense. Shouldn't the kernel
> deny this?
> If I do a netstat I see the following:
>
> mhpa9rec:~# netstat -p | grep 3000
> tcp 0 0 mhpa9rec:3000 mhpa9rec:3000 ESTABLISHED1351/sock
>
I fail to see why the kernel needs to deny this?
If I were to create a port blocker your example woult fit nicely when
clarifying how to do this (without reading and writing of course).
In this way I would be able to programmatically occupy different ports
without using many resources, thus controlling which ports are free for
other (possible malicious) sockets.

Do I make sense? It is a long time ago I did this kind of lowlevel
programming... thank god for IPTables :)

Sincerely,
Dennis Petersen