Paramiko: "not a valid DSA private key file"

June 22, 2024

I am trying to connect to some SFTP using a private key file that looks like:

---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ---- Subject: L0709146 Comment: "1024-bit dsa, L0709146@pxz102, Wed Jan 12 2022 11:25:54 +010\ 0" P2/bla...bla...bla ---- END SSH2 ENCRYPTED PRIVATE KEY ----

Using the following code:

import paramiko path = "path/to/my/file" transport = paramiko.Transport((self.host, self.port)) transport.connect(username=self.user,pkey=paramiko.DSSKey.from_private_key(open(path))) # ^^^ Error line ^^^ #transport.connect(username=self.user,pkey=paramiko.RSAKey.from_private_key(open(path))) #transport.connect(username=self.user,pkey=paramiko.ECDSAKey.from_private_key(open(path))) sftp = paramiko.SFTPClient.from_transport(transport) logging.info(sftp.listdir())

I'm not sure but I understand that is a DSA private key file, but I obtained the error:

paramiko.ssh_exception.SSHException: not a valid DSA private key file

I tried with other options but, a similar error

paramiko.ssh_exception.SSHException: not a valid RSA private key file paramiko.ssh_exception.SSHException: not a valid EC private key file paramiko.ssh_exception.SSHException: not a valid OPENSSH private key file

I used the FileZilla client, I hadn't problem connecting to the SFTP, I don't get why with Python I have problems.

1 Answer

You have a private key in rarely used ssh.com format. Paramiko does not support it. You have to convert it to the OpenSSH format.

You can use ssh-keygen like this:

ssh-keygen -i -f sshcomkey > opensshkey

On Windows you can also use PuTTYgen.

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