Source code for soma.crypt

# -*- coding: utf-8 -*-
'''
Functions to manage private/public keys encryption.
This module needs Crypto module.
'''

from __future__ import absolute_import
from Crypto.PublicKey import RSA
from base64 import b64decode, b64encode
import Crypto
import six
from six.moves import range

if [int(x) for x in Crypto.__version__.split('.')] < [2, 1]:
    # pyrypro <= 2.0.x is not suitable since it is missing needed functions
    # such as exportKey() and importKey()
    raise ImportError('Crypto module (pycrypto) is too old for soma.crypt')


[docs]def generate_RSA(bits=2048): ''' Generate an RSA keypair with an exponent of 65537 in PEM format param: bits The key length in bits Return private key and public key ''' if [int(x) for x in Crypto.__version__.split('.')] < [2, 1]: import random def gen_func(n): return ''.join([chr(random.randrange(0, 256, 1)) for i in range(n)]) new_key = RSA.generate(bits, gen_func) else: new_key = RSA.generate(bits) public_key = new_key.publickey().exportKey("PEM") private_key = new_key.exportKey("PEM") return private_key, public_key
[docs]def encrypt_RSA(public_key_loc, message): ''' param: public_key_loc Path to public key param: message String to be encrypted return base64 encoded encrypted string ''' key = open(public_key_loc, "rb").read() rsakey = RSA.importKey(key) if not isinstance(message, six.binary_type): message = message.encode() encrypted = rsakey.encrypt(message, None)[0] return b64encode(encrypted)
[docs]def decrypt_RSA(private_key_loc, package): ''' param: public_key_loc Path to your private key param: package String to be decrypted return decrypted string ''' key = open(private_key_loc, "rb").read() rsakey = RSA.importKey(key) decrypted = rsakey.decrypt(b64decode(package)) return decrypted