How to ssh connect through Python Paramiko with ppk public key

Question:

I’m using Paramiko to connect through SSH to a server.

Basic authentication works well, but I can’t understand how to connect with public key.

When I connect with PuTTY, the server tell me this:

Using username "root".
Authenticating with public key "[email protected]"
Passphrase for key "[email protected]": [i've inserted the passphrase here]
Last login: Mon Dec  5 09:25:18 2011 from ...

I connect to it with this ppk file:

PuTTY-User-Key-File-2: ssh-rsa
Encryption: aes256-cbc
Comment: [email protected]
Public-Lines: 4
[4 lines key]
Private-Lines: 8
[8 lines key]
Private-MAC: [hash]

With basic auth the error I get (from the log) is:

DEB [20111205-09:48:44.328] thr=1   paramiko.transport: userauth is OK
DEB [20111205-09:48:44.927] thr=1   paramiko.transport: Authentication type (password) not permitted.
DEB [20111205-09:48:44.927] thr=1   paramiko.transport: Allowed methods: ['publickey', 'gssapi-with-mic']

I’ve tried to include that ppk file and set to auth_public_key, but didn’t work.

Can you help me?

Asked By: apelliciari

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Answers:

Ok @Adam and @Kimvais were right, Paramiko cannot parse .ppk files.

So the way to go (thanks to @JimB too) is to convert .ppk file to OpenSSH private key format; this can be achieved using PuTTYgen as described here.

Then it’s very simple getting connected with it:

import paramiko
ssh = paramiko.SSHClient()

ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect('<hostname>', username='<username>', password='<password>', key_filename='<path/to/openssh-private-key-file>')

stdin, stdout, stderr = ssh.exec_command('ls')
print stdout.readlines()
ssh.close()
Answered By: apelliciari

To create a valid DSA format private key supported by Paramiko in Puttygen.

Click on Conversions then Export OpenSSH Key

enter image description here

Answered By: Abdul Hamid

For me I doing this:

import paramiko
hostname = 'my hostname or IP' 
myuser   = 'the user to ssh connect'
mySSHK   = '/path/to/sshkey.pub'
sshcon   = paramiko.SSHClient()  # will create the object
sshcon.set_missing_host_key_policy(paramiko.AutoAddPolicy()) # no known_hosts error
sshcon.connect(hostname, username=myuser, key_filename=mySSHK) # no passwd needed

works for me pretty ok

Answered By: Carlos M G T

@VonC’s answer to (deleted) duplicate question:

If, as commented, Paraminko does not support PPK key, the official solution, as seen here, would be to use PuTTYgen.

But you can also use the Python library CkSshKey to make that same conversion directly in your program.

See "Convert PuTTY Private Key (ppk) to OpenSSH (pem)"

import sys
import chilkat

key = chilkat.CkSshKey()

#  Load an unencrypted or encrypted PuTTY private key.

#  If  your PuTTY private key is encrypted, set the Password
#  property before calling FromPuttyPrivateKey.
#  If your PuTTY private key is not encrypted, it makes no diffference
#  if Password is set or not set.
key.put_Password("secret")

#  First load the .ppk file into a string:

keyStr = key.loadText("putty_private_key.ppk")

#  Import into the SSH key object:
success = key.FromPuttyPrivateKey(keyStr)
if (success != True):
    print(key.lastErrorText())
    sys.exit()

#  Convert to an encrypted or unencrypted OpenSSH key.

#  First demonstrate converting to an unencrypted OpenSSH key

bEncrypt = False
unencryptedKeyStr = key.toOpenSshPrivateKey(bEncrypt)
success = key.SaveText(unencryptedKeyStr,"unencrypted_openssh.pem")
if (success != True):
    print(key.lastErrorText())
    sys.exit()
Answered By: Martin Prikryl