Synnefo » snf-ganeti

  root_logger.setLevel(logging.NOTSET)

def LoadPrivateKeys(options):

  """Load the list of available private keys

  It loads the standard ssh key from disk and then tries to connect to

  the ssh agent too.

  @rtype: list

  @return: a list of C{paramiko.PKey}

  """

  try:

    agent = paramiko.Agent()

    agent_keys = agent.get_keys()

  except paramiko.SSHException, err:

    # this will only be seen when the agent is broken/uses invalid

    # protocol; for non-existing agent, get_keys() will just return an

    # empty tuple

    logging.warning("Can't connect to the ssh agent: %s; skipping its use",

                    err)

    agent_keys = []

  return [private_key] + list(agent_keys)

def LoginViaKeys(transport, username, keys):

  """Try to login on the given transport via a list of keys.

  @param transport: the transport to use

  @param username: the username to login as

  @type keys: list

  @param keys: list of C{paramiko.PKey} to use for authentication

  @rtype: boolean

  @return: True or False depending on whether the login was

      successfull or not

  """

  for private_key in keys:

    try:

      transport.auth_publickey(username, private_key)

      fpr = ":".join("%02x" % ord(i) for i in private_key.get_fingerprint())

      if isinstance(private_key, paramiko.AgentKey):

        logging.debug("Authentication via the ssh-agent key %s", fpr)

      else:

        logging.debug("Authenticated via public key %s", fpr)

      return True

    except paramiko.SSHException:

      continue

  else:

    # all keys exhausted

    return False

def main():

  """Main routine.

  """

  (options, args) = ParseOptions()

  SetupLogging(options)

  all_keys = LoadPrivateKeys(options)

      if LoginViaKeys(transport, username, all_keys):

      else: