deb-sahara/sahara/utils/crypto.py
xiexs a60ec7aa5b Optimize "open" method with context manager
Use opening context manager to open a file.

Change-Id: I4744f3e7650d3d3393c5c019216b241ec77710eb
2015-11-27 04:23:12 -05:00

61 lines
2.0 KiB
Python

# Copyright (c) 2013 Mirantis Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import os
from oslo_concurrency import processutils
import paramiko
import six
from sahara import exceptions as ex
from sahara.i18n import _
from sahara.utils import tempfiles
def to_paramiko_private_key(pkey):
"""Convert private key (str) to paramiko-specific RSAKey object."""
return paramiko.RSAKey(file_obj=six.StringIO(pkey))
def generate_key_pair(key_length=2048):
"""Create RSA key pair with specified number of bits in key.
Returns tuple of private and public keys.
"""
with tempfiles.tempdir() as tmpdir:
keyfile = os.path.join(tmpdir, 'tempkey')
args = [
'ssh-keygen',
'-q', # quiet
'-N', '', # w/o passphrase
'-t', 'rsa', # create key of rsa type
'-f', keyfile, # filename of the key file
'-C', 'Generated-by-Sahara' # key comment
]
if key_length is not None:
args.extend(['-b', key_length])
processutils.execute(*args)
if not os.path.exists(keyfile):
raise ex.SystemError(_("Private key file hasn't been created"))
with open(keyfile) as keyfile_fd:
private_key = keyfile_fd.read()
public_key_path = keyfile + '.pub'
if not os.path.exists(public_key_path):
raise ex.SystemError(_("Public key file hasn't been created"))
with open(public_key_path) as public_key_path_fd:
public_key = public_key_path_fd.read()
return private_key, public_key