Windows-to-*nix public key authentication

I've worked with lots of servers, most of which I cannot access directly, so I often use remote access: Remote Desktop Connection or Terminal Services in Windows, and ssh in *nix.

While I do have PasswordSafe to remember all those passwords, I'm the lazy admin type, so I often opt for password-less authentication using public keys. For this, I use PuTTY, et. al.

1. First, I generate an RSA key using PuTTYgen. I don't enter anything for the passphrase. Warning: NOT recommended for production servers!


2. I save the public and secret keys (in .PPK format) in a directory. I also cut and paste the RSA string in a text file, key.txt.


3. For now, the remote box is configured for "normal" ssh, that is, through password authentication. So, I copy over the RSA string file to the remote box:
   
   
   

   C:\> pscp \path\to\key.txt user@remote-host:/home/user/.

   
   



4. I log on to the remote host using PuTTY, and do the following:
   
   
   

   $ mkdir .ssh
   $ mv key.txt .ssh/authorized_keys
   $ chmod 700 .ssh; chmod 600 .ssh/authorized_keys

   
   



5. I also edit the SSHd config file, /etc/ssh/sshd_config, with the following parameters:
   
   
   

   RSAAuthentication yes
   PubkeyAuthentication yes
   AuthorizedKeysFile .ssh/authorized_keys
   PasswordAuthentication no
   PermitRootLogin no

   
   



6. SSHd is then restarted.


7. Back in Windows, I launch PuTTY, and enter the host name for the remote box. In the SSH/Auth category, I place the private key file saved earlier. I save the session, named remote-nopass.


8. I then launch Pageant, drill down to Saved Sessions > remote-nopass. It will bring up the SSH login page, where I enter my login name, after which, I am authorized through the pubkey, and log in to the SSH session.

Seems tedious at first, but I can then export key.txt to other remote servers, and just save sessions for Pageant's use. Pageant is conveniently located in the system tray within reach.