I've created a python library that uses both RSA and AES encryption to allow for hybrid encryption of text or images. I am wondering if I should implement a keystore and/or a better key management system and if that would be applicable or useful for my purposes (I plan to implement this in a chat flask web-app). Additionally I would like to know if my library is cryptographically secure and if I can make any improvements to my code in order to make it more efficient. Here is the code for my library:
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import rsa, padding
from cryptography.fernet import Fernet
import io
class RSAEncryption:
def __init__(self):
try:
self.private_key = rsa.generate_private_key(public_exponent=65537, key_size=2048)
self.public_key = self.private_key.public_key()
except Exception as e:
print("Error generating RSA key: ", e)
def encrypt(self, data):
try:
ciphertext = self.public_key.encrypt(data, padding.OAEP(mgf=padding.MGF1(algorithm=hashes.SHA256()), algorithm=hashes.SHA256(), label=None))
return ciphertext
except Exception as e:
print("Error encrypting data with RSA: ", e)
def decrypt(self, ciphertext):
try:
plaintext = self.private_key.decrypt(ciphertext, padding.OAEP(mgf=padding.MGF1(algorithm=hashes.SHA256()), algorithm=hashes.SHA256(), label=None))
return plaintext.decode()
except Exception as e:
print("Error decrypting data with RSA: ", e)
class AESEncryption:
def __init__(self):
try:
self.key = Fernet.generate_key()
self.cipher = Fernet(self.key)
except Exception as e:
print("Error generating AES key: ", e)
def encrypt(self, data):
try:
ciphertext = self.cipher.encrypt(data)
return ciphertext
except Exception as e:
print("Error encrypting data with AES: ", e)
def decrypt(self, ciphertext):
try:
plaintext = self.cipher.decrypt(ciphertext)
return plaintext.decode()
except Exception as e:
print("Error decrypting data with AES: ", e)
class HybridEncryption:
def __init__(self):
self.rsa_encryption = RSAEncryption()
self.aes_encryption = AESEncryption()
def encrypt_text(self, text):
try:
aes_ciphertext = self.aes_encryption.encrypt(text)
encrypted_key = self.rsa_encryption.encrypt(self.aes_encryption.key)
return aes_ciphertext, encrypted_key
except Exception as e:
print("Error encrypting text: ", e)
def decrypt_text(self, aes_ciphertext, encrypted_key):
try:
decrypted_key = self.rsa_encryption.decrypt(encrypted_key)
aes_decryption = Fernet(decrypted_key)
plaintext = aes_decryption.decrypt(aes_ciphertext)
return plaintext.decode()
except Exception as e:
print("Error decrypting text: ", e)
def encrypt_image(self, image_path, chunk_size=1024):
try:
with open(image_path, 'rb') as image_file:
data = io.BytesIO(image_file.read())
chunks = iter(lambda: data.read(chunk_size), b'')
encrypted_chunks = []
for chunk in chunks:
encrypted_chunk = self.aes_encryption.encrypt(chunk)
encrypted_chunks.append(encrypted_chunk)
encrypted_key = self.rsa_encryption.encrypt(self.aes_encryption.key)
return encrypted_chunks, encrypted_key
except Exception as e:
print("Error encrypting image: ", e)
def decrypt_image(self, encrypted_chunks, encrypted_key, image_path):
try:
decrypted_key = self.rsa_encryption.decrypt(encrypted_key)
aes_decryption = Fernet(decrypted_key)
decrypted_data = b''.join([aes_decryption.decrypt(chunk) for chunk in encrypted_chunks])
with open(image_path, 'wb') as image_file:
image_file.write(decrypted_data)
except Exception as e:
print("Error decrypting image: ", e)
