Promiscuous ports under Linux

[Marko Rauhamaa]

Peter Pearson <pkpearson at nowhere.invalid>:

> Cobbling together a minimalist ethernet-sniffing program, I was hoping
> to use this simple mechanism for setting the socket to "promiscuous
> mode" (to see all traffic going past, instead of just traffic
> addressed to my machine):
>
>     s.ioctl(socket.SIO_RCVALL, socket.RCVALL_ON)
>
> Unfortunately, it seems that that mechanism is available under Windows
> but not under Linux.

Can't remember having done that for years, if ever. However, one place
to give you pointers is running:

     strace tcpdump

as root. It reveals all the system calls involved.


Marko