# Import the library we install in step 1

import cryptography

import base64

import os

from cryptography.hazmat.backends import default_backend

from cryptography.hazmat.primitives import hashes

from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC

from cryptography.fernet import Fernet

SALT = b'SOME_RANDOM_SALT'

def Encrypter(filename, password):

password = password.encode()

kdf = PBKDF2HMAC(

algorithm=hashes.SHA512(),

length=32,

salt=SALT,

iterations=100000,

backend=default_backend()

)

key = base64.urlsafe_b64encode(kdf.derive(password))

fernet = Fernet(key)

print('Opening file: ' + filename)

with open(filename, 'rb') as f:

data = f.read()

print('Encrypting...')

encryptedData = fernet.encrypt(data)

print('Saving encrypted: ' + filename + '.enc')

with open(filename + '.enc', 'wb') as f:

f.write(encryptedData)

print("----")

print("DONE")

def Decrypter(filename, password):

password = password.encode()

kdf = PBKDF2HMAC(

algorithm=hashes.SHA512(),

length=32,

salt=SALT,

iterations=100000,

backend=default_backend()

)

key = base64.urlsafe_b64encode(kdf.derive(password))

fernet = Fernet(key)

# Open file

print('Opening encrypted file: ' + filename)

with open(filename, 'rb') as f:

encryptedFileData = f.read()

# Decrypt

print('Decrypting file...')

decryptedFileData = fernet.decrypt(encryptedFileData)

# Let's remove the .enc that we added when encrypting

decryptedFilename = filename.replace('.enc','')

# Let's add dec prefix just in case the old unecrypted file

# is still there.

decryptedFilename = 'dec_' + decryptedFilename

print('Saving decrypted file data: ' + decryptedFilename)

with open(decryptedFilename, 'wb') as f:

f.write(decryptedFileData)

print("----")

print("DONE")