Has anyone used PuTTY and OpenSSH?

[ron.peterson at yellowbank.com (ron.peterson at yellowbank.com)]

On Sun, May 25, 2003 at 10:08:37PM -0400, Bill Horne wrote:

> I'd like to set up ssh mode 2 authentication for incoming ssh requests 
> from a PuTTY client: PuTTY is an ssh client that runs under Win32, and 
> it's my prefered client for that platform.
> 
> I created public and private keys for my server by using the keygen 
> functions of ssh, and tried to get it to accept a logon from a PuTTY 
> client which had keys generated by the PuTTY key generator program,
> but they wouldn't talk to one another.
> 
> If you've used PuTTY with OpenSSY_3.1p1, please tell me how to go 
> about it.

Run puttygen (if you didn't get it w/ putty, go to putty's download page
and get the whole kit and kaboodle).  Generate an RSA v2 key - 1024 bits
should be fine.  RSA1 and DSA probably work too, but aren't as secure.

Save both the private and public keys somewhere - say
c:\mykeys\id_rsa2.pub and c:\mykeys\id_rsa2.

Start PuTTY.  Set the server name, select SSH, pick your favorite
colors, etc.  Under 'Connection', set the auto-login username to your
username.  Under SSH, prefer protocol 2.  Under SSH/Auth, enter the path
to your private key file.

Save your setup.

scp your public key to the machine you'd like to log into (you can use
pscp that you just installed to do this).  Make sure you don't
inadvertantly overwrite any identically named public keys on the
recieving end, by doing somthing like 'scp id_rsa.pub
rpeterso at mhc.mtholyoke.edu:.ssh/.'

Assuming that the machine you're logging into runs OpenSSH, you'll need
to edit the public key file to get rid of extra crufty stuff that
puttygen puts in.  Take the public key that looks like:

---- BEGIN SSH2 PUBLIC KEY ----
Comment: "rsa-key-20030311"
AAAAB3NzaC1yc2EAAAABJQAAAIBdiF7KbXcOj6KMl+6eitU7vEUtVzyMdIqYgHHg
A7OND7hjnPKebvGqYCsVOTrxyy6wOhWdqgKNlVO+XawxFgZteQIxSlxsZo3nLUJO
9Y2I0/csvi5LbfUO3IOIjjK/d37NZCGPtbd90EYHpNC5HZVqQ35cbCENxzN0sgUl
zRAOzQ==
---- END SSH2 PUBLIC KEY ----

and convert to be like:

ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAIBdiF7KbXcOj6KMl+6eitU7vEUtVzyMdIqYgHHgA7OND7hjnPKebvGqYCsVOTrxyy6wOhWdqgKNlVO+XawxFgZteQIxSlxsZo3nLUJO9Y2I0/csvi5LbfUO3IOIjjK/d37NZCGPtbd90EYHpNC5HZVqQ35cbCENxzN0sgUlzRAOzQ==

That is to say (in case your email client auto-line-wraps) remove all
linebreaks from the actual key portion.  Delete everything else.  Put
'ssh-rsa' at the front.  Probably best to do this edit in *nix, so you
don't get weird DOS linefeed characters in your file.

Append this text to your ~/.ssh/authorized_keys file.

-- 
Ron Peterson                          -o)
Network & Systems Manager             /\\
Mount Holyoke College                _\_v
http://www.mtholyoke.edu/~rpeterso   ---- 




-- 
Ron Peterson                   -o)
87 Taylor Street               /\\
Granby, MA  01033             _\_v
https://www.yellowbank.com/   ----