OpenSSH sftp login using RSA/DSA keys

[nacek]

Hello guys
I'm trying to configure a secure SFTP server on debian.

I've succesfuly configured it to allow users to log on only to file service and to chroot their home dir, so they cant mess with my system.

But now I would like clients to need key, which I generate to logon to sftp, I've been searching on internet for last two days and without succes.

I installed a clean debian with openssh, and I found out that I can login using that RSA/DSA key but only to ssh and that is not what I need, when logged to sftp, it requires user pass, not pass to my generated key, and also I didn't find and option to send key with sftp like way you do when logging in with ssh

ssh -i /key/mykey user at server (cant use at symbol )


So guys, is there a way to allow users to log in using SFTP ONLY - NOT ssh with keys I generate for them?

Thank you

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EDIT: oh thank god, I figured it out

it is not that difficult, you need to be very careful with file permisions

users Chrooted dir must be chmod 750 and it must be chown root:sftpgoup
and directory containing public keys must be chmod 755 and keyfile 744 (Authorized_keys)

If anybody needs help with OpenSSH, just post it here, I did quite a bit of research on the matter, so I may be able to help you