A shell script to automatically configure a Raspberry Pi (Raspbian) without manual login

Purpose: To allow basic configuration of a Raspberry Pi (especially ssh keys) without interaction. This is mainly useful when you have lots of pis to confgure, or if you regularly reinstall a pi from scratch.

The script will:

• log in to the pi using ssh with the default password for the 'pi' user.
• copy an ssh public key from the host to the pi user.
• create a new user on the pi with the same username as the user that invoked the script.

Assumptions:

• you know the DNS name or IP address of the pi.
• the pi is a standard Rasbian install with: a) ssh enabled b) the user 'pi's password set to the default - raspberry

Security Considerations:

• Ordinarily the use fo sshpass in a script would be frowned upon as it's insecure. In this instance, the default user/password on the pi is very much public knowledge.
• The use of ssh-keyscan could be considered insecure but this script is designed to be used in a controlled development LAN where man-in-the-middle attacks are not a practical concern.

Future enhancements:

• if the script is called without a parameter it could scan the local subnet for MAC addresses that match the Rasberry Pi range(es) and present these as a list with IP address.