Testing Aton Connect SSH (PuTTY)

AtonPuTTY (“Aton Connect SSH (PuTTY)”) combines much of the PuTTY version 0.62 open source “C” code with UWP C# and C++ code as a user interface.  This allows most of the functionality of PuTTY to be used on modern Windows 10 platforms, both desktop and mobile.

You need to test AtonPuTTY against a Linux or Unix SSH server that offers shell access.  Often you have an SSH server with shell access for which you may have SSH keys.  The procedure is then:

  • If you want to use a login and password, make sure that the “Private key file for authentication:” field on the SSH Authentication configuration page is blank.
  • To use an SSH key, set the “Private key file for authentication:” field on the SSH Authentication configuration page to the private key (with extension .ppk) corresponding to the public key stored in the SSH Server in the “authorized_keys” file in the ~/.ssh folder in the base folder of the server user corresponding to the login command. The public key will be on a single line, with no CR characters.  If you use AtonPutty or PuttyGen to generate the SSH Keys, do a copy paste from the public key field, not by using the “Save public key” button.  If you have more than one key in the “authorized_keys” file then each key is separated by a CR character.

Otherwise the simplest technique is to use is to install Ubuntu with SSH Server on a virtual machine.  For example, in the Microsoft Windows 10 Professional environment you can use the Hyper-V process to install the Ubuntu distribution as shown in this link.  Once Ubuntu is installed, you additionally need to install the SSH Server as described here.  Note that an SSH Client but not the server is already installed by default when Ubuntu is installed.

Login to Aton PuTTY can occur by simple use of a login and password, but make sure that the “Private key file for authentication:” field on the SSH Authentication configuration page is blank.

Alternately, use can be made of SSH keys, usually in the form of RSA keys. You can use AtonPuTTY, PuTTY,  or  ssh-keygen as supplied with the Ubuntu SSH client or server.  Generating SSH keys with PuTTYgen is described here.  A similar approach is used with AtonPuTTY.  One can also use the command line tool ssh-keygen as supplied with the Ubuntu SSH client or server as described here.

Some points to note when using SSH keys:

  • The public key used by the SSH server is stored in the ~/.ssh folder in the “authorized_keys” file for the login supplied when logging in with AtonPuTTY.
  • The “authorized keys” file may contain more than one key, each one line, separate from the next key by the CR character.
  • Each key is one line, with no intervening CR characters. So, installing the key into the “authorized_keys” file can done by using the public key obtained from a copy paste from the AtonPuTTY public key field, not by using the “Save public key” button on PuTTY or the “Public: All” dropdown on AtonPuTTY which generates public key files with intervening CR characters and other format variations.
  • The corresponding private key file path is installed into the “Private key file for authentication:” field on the SSH Authentication configuration. This suppresses asking for a user password and instead uses the public key in the ~/.ssh/authorized_keys file on the server which is then compared to the private key stored in the “Private key file for authentication:” field on the SSH Authentication configuration page.
  • If the private key contains a password, as recommended, then the login will ask for that key password. Note that there is no equivalent to PuTTY Pageant for AtonPuTTY, so the key password will need to be reentered if AtonPuTTY is restarted.
  • If you prefer using the Windows GUI methods instead of Linux command lines, then use of the FileZilla client can ease your way (using port 22).
  • Provision is made to allow import and export of keys and other files to/from the users Pictures library folder. This gives the user access to files otherwise stored internally to the AtonPuTTY application.