Hi all,
I am trying to replace the login interface in my Linux (Fedora) so that you will have to use the IButton (Dallas ibutton 1 wire) connected to the serial port as your password. I already made the software that checks the code in the button through the serial port, but i don't know how to link it to the login ? I want the user to be asked for his username , then be asked to attach the ibutton to the readed, and his login will be authenticated. I know that it might not be straight forwards, but i know i can do it if someone gives me the right directions.

Much apprciated,
Regards

This is exactly what PAM (Pluggable Authentication Modules) is for.
PAM allows for authentication methods beyond the normal /etc/passwd scheme.

http://linux.kernel.org/pub/linux/libs/pam


Good Luck