Better Key Storage With Blackbox, RSA, Redis, and the Fernet Algorithm in Django


Python lacks a proper key store.  This is an unnerving issue when trying to build a secure application. More troubling is the plain text storage of RSA keys. This article examines a process for storing keys in an encrypted manner on black box as well as the storage of keys using the Fernet algorithm and encryption through RSA in Django using redis for speed.


Unlike Java which already has a key store, Python lacks the ability to store keys for data encryption. Python developers are left with only basic methods for storing keys and this often means doing so in plain text.

That method is inexplicably terrible when working with FERPA/HIPPA and especially the increasingly difficult state guidelines for storing sensitive information.


One solution, of many, is to use Stack Exchange black box to store keys and the Fernet algorithm to encrypt the keys in a cache. In this way keys are stored in an encrypted format in a hidden file as well as in a secure format in memory.

Black Box

Stack Exchange’s Black Box offers a perfect storage solution for keys using a gpg keyring to encrypt data. The tool was made to store secrets in a git repository.

Check out my Python API for reading files from black box. It is possible to add a user to the administrator file in order to avoid entering a password each time.

Storing Encrypted Keys in Django

Once the keys are encrypted and accessible, a large application needs to ensure speed. To help alleviate sluggishness, it is possible to store keys using the Fernet algorithm in any cache that Django provides.

It is possible to use the cryptography package for this task.

from cryptography.fernet import Fernet
from django.core.cache import cache

key = Fernet.generate_key()
f = Fernet(key)
token = f.encrypt(b"my deep dark secret")
cache.set('my_token', token)


It is possible to recreate a secure keystore using a mix of Stack Exchange Black Box and the Fernet algorithm when creating a Django application. The implementation above may not be production ready but is a proof of concept.