user@home:~/.ssh# sudo dropbearkey
Must specify a key filename
Usage: dropbearkey -t -f [-s bits]
Options are:
-t type Type of key to generate. One of:
rsa dss -f filename Use filename for the secret key -s bits Key size in bits, should be a multiple of 8 (optional) (DSS has a fixed size of 1024 bits) -y Just print the publickey and fingerprint for the private key in .

user@home:~/.ssh# sudo dropbearkey -y -f ~/.ssh/id_rsa Public key portion is: ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAyyA8wePstPC69PeuHFtOwyTecByonsHFAjHbVnZ+h0dpomvLZxUtbknNj3/c7MPYKqKBOx9gUKV/diR/mIDqsb405MlrI1kmNR9zbFGYAAwIH/Gxt0Lv5ffwaqsz7cECHBbMojQGEz3IH3twEvDfF6cu5p00QfP0MSmEi/ieB+W+h30N user@home Fingerprint: md5 a4:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx


First, generate your identity key on ‘home’

user@home: sudo dropbearkey -t rsa -f ~/.ssh/id_rsa

Since dropbear stores its keys in different format, it needs to be converted for a standard SSH server:

user@home: sudo dropbearkey -y -f ~/.ssh/id_rsa | grep “^ssh-rsa ” >> dropbear_rsa_pub_key

Now copy or (concatenate) ‘authorized_keys’ to ~/.ssh on ‘webhost’.

user@home: sudo scp dropbear_rsa_pub_key 192.168.1.143:.ssh/drsa_pub
user@webhost: cd ~/.ssh
user@webhost: cat drsa_pub cat >> authorized_keys

Ensure that permissions on this file are set to 600.

user@webhost: sudo chmod 600 authorized_keys

You should now be able to ssh without a password.


user@home:~# ssh user@webhost -i ~/.ssh/id_rsa

Notice that you need to explicitly specify the identity file on the command line. Dropbear does not automatically look for it like OpenSSH does.


thanks!!
http://yorkspace.wordpress.com/2009/04/08/using-public-keys-with-dropbear-ssh-client/

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