Python Symmetric String Encryption with key generation using Cryptography. Random key generation using strong secure random number generator. AES-256 authenticated encryption using GCM. BASE64 encoding as. (String plainText) try // GENERATE key // TODO key should only be generated once and then managed with a key manager/key. Run import pyaes, pbkdf2, binascii, os, secrets # Derive a 256-bit AES encryption key from the password password = 's3cr3t.c0d3' passwordSalt = os.urandom (16) key = pbkdf2.PBKDF2 (password, passwordSalt).read (32) print ('AES encryption key:', binascii.hexlify (key)).
I'm trying to build two functions using PyCrypto that accept two parameters: the message and the key, and then encrypt/decrypt the message.
I found several links on the web to help me out, but each one of them has flaws:
This one at codekoala uses os.urandom, which is discouraged by PyCrypto.
Moreover, the key I give to the function is not guaranteed to have the exact length expected. What can I do to make that happen ?
Also, there are several modes, which one is recommended? I don't know what to use :/
Finally, what exactly is the IV? Can I provide a different IV for encrypting and decrypting, or will this return in a different result?
Here's what I've done so far:
The following python program demonstrates how to perform AES 256 encryption and decryption using the pycrypto library. Please note that this example is written in Python 3.
First ensure that pycrypto library is installed on your system by running the following command,
In the following python 3 program, we use pycrypto classes for AES 256 encryption and decryption. The program asks the user for a password (passphrase) for encrypting the data. This passphrase is converted to a hash value before using it as the key for encryption. The following program encrypts a sample text and then prints both the encrypted message and decrypted message on the console.
Here is the above program in action,
Note that the above program uses SHA256 algorithm to generate the key from the passphrase. If you want high level of security, this should be replaced with password based key derivation function PBKDF2. The following example uses the PBKDF2 to generate the key,