Simplify RSA encode and decode messages with the python rsa library.

rsa.py

import base64
import os
import rsa


def load_priv_key(path):
    path = os.path.join(os.path.dirname(__file__), path)
    with open(path, mode='rb') as privatefile:
        keydata = privatefile.read()
    return rsa.PrivateKey.load_pkcs1(keydata)


def load_pub_key(path):
    path = os.path.join(os.path.dirname(__file__), path)
    with open(path, mode='rb') as pubfile:
        keydata = pubfile.read()
    return rsa.PublicKey.load_pkcs1(keydata)


def verify(message, signature, pubkey):
    signature = base64.b64decode(signature)
    return rsa.verify(message, signature, pubkey)


def sign(message, privkey):
    signature = rsa.sign(message, privkey, 'SHA-1')
    return base64.b64encode(signature)


def create_keys():
    (pubkey, privkey) = rsa.newkeys(512, True, 8)
    with open("id_rsa.pub", "w") as text_file:
        text_file.write(pubkey.save_pkcs1().decode('ascii'))
    with open("id_rsa", "w") as text_file:
        text_file.write(privkey.save_pkcs1().decode('ascii'))

test.py

from . import rsa

# create keys (saved in same dir)
rsa.create_keys()

message = 'Go left at the blue tree'.encode('utf-8')
privkey = rsa.load_priv_key('id_rsa')
pubkey = rsa.load_pub_key('id_rsa.pub')

# sign message
signature = rsa.sign(message, privkey)

# verify signature
is_verified = rsa.verify(message, signature, pubkey)
print(is_verified)