How to encrypt JSON in python

Question

I have a JSON file. I am running a program, in python, where data is extracted from the JSON file. Is there any way to encrypt the JSON file with a key, so that if someone randomly opens the file, it would be a mess of characters, but when the key is fed to the program, it decrypts it and is able to read it? Thanks in advance.

Answer 1

Yes, you can encrypt a .json file. Make sure you install the cryptography package by typing

pip install cryptography
# or on windows:
python -m pip install cryptography

Then, you can make a program similar to mine:

#this imports the cryptography package
from cryptography.fernet import Fernet

#this generates a key and opens a file 'key.key' and writes the key there
key = Fernet.generate_key()
with open('key.key','wb') as file:
    file.write(key)

#this just opens your 'key.key' and assings the key stored there as 'key'
with open('key.key','rb') as file:
    key = file.read()

#this opens your json and reads its data into a new variable called 'data'
with open('filename.json','rb') as f:
    data = f.read()

#this encrypts the data read from your json and stores it in 'encrypted'
fernet = Fernet(key)
encrypted = fernet.encrypt(data)

#this writes your new, encrypted data into a new JSON file
with open('filename.json','wb') as f:
    f.write(encrypted)

Note that this block:

with open('key.key','wb') as file:
    file.write(key)

#this just opens your 'key.key' and assigns the key stored there as 'key'
with open('key.key','rb') as file:
    key = file.read()

isn't necessary. It is just a way to store the generated key in a safe place, and read it back in. You can delete that block if you want.

Let me know if you need further assistance :)

Answer 2

you can do it with Asymmetric Encryption and Decryption. here is full article article keep this in mind you should encode your string data before encryption

to read the json data :

data = json.load(open('data.json'))

for encryption:

python -m pip install cryptography

to create/store keys and encrypt the json data you should do this:

from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import padding

def create_keys():
    private_key = rsa.generate_private_key(
        public_exponent=65537,
        key_size=2048,
        backend=default_backend()
    )
    public_key = private_key.public_key()

    pem = private_key.private_bytes(
        encoding=serialization.Encoding.PEM,
        format=serialization.PrivateFormat.PKCS8,
        encryption_algorithm=serialization.NoEncryption()
    )
    with open('private_key.pem', 'wb') as f:
        f.write(pem)
    pem = public_key.public_bytes(
        encoding=serialization.Encoding.PEM,
        format=serialization.PublicFormat.SubjectPublicKeyInfo
    )
    with open('public_key.pem', 'wb') as f:
        f.write(pem)


def get_private_key():
    with open("private_key.pem", "rb") as key_file:
        private_key = serialization.load_pem_private_key(
            key_file.read(),
            password=None,
            backend=default_backend()
        )
    return private_key

def get_public_key():
    with open("public_key.pem", "rb") as key_file:
        public_key = serialization.load_pem_public_key(
        key_file.read(),
        backend=default_backend()
    )
    return public_key

def encrypt():
    # createKeys()
    public_key = get_public_key()
    massage = str(data).encode('utf-8')
    encrypted = public_key.encrypt(massage, padding.OAEP(padding.MGF1(hashes.SHA256()), hashes.SHA256(), None))
    private_key = get_private_key()
    original_message = private_key.decrypt(encrypted, padding.OAEP(padding.MGF1(hashes.SHA256()), hashes.SHA256(), None))

    return original_message.decode('utf-8')

and for decryption you should do this:

original_message = private_key.decrypt(
    encrypted,
    padding.OAEP(
        mgf=padding.MGF1(algorithm=hashes.SHA256()),
        algorithm=hashes.SHA256(),
        label=None
    )
)