Public key authentication with ssh

IoT Modules WP Series
4

The problem was due to insecure file system permissions. Here is a list of commands that generates the key and sets the right permissions (the hardest to find was the first):

dropbearkey -t rsa -f ~/.ssh/id_rsa | grep ssh-rsa > .ssh/authorized_keys
chown root /home/root
chmod 700 /home/root
chmod 700 ~/.ssh
chmod 600 ~/.ssh/id_rsa
chmod 600 ~/.ssh/authorized_keys

The '/etc/dropbear/authorized_keys ’ file is uneccessary. Do use the dropbearkey command to generate the key-pair though.

IMPORTANT: Since the owner of /home/root is ‘appfwupdateService’ by default, for safety reasons you shoud switch back to this user and default permissions (755) before doing a firmware update.