OpSep Python Client Library

In order to use this client library, you will need to be running an OpSep Server to protect your RSA private key.

For simplicty, we'll use an OpSep server hosted by SecondGuard at https://test.secondguard.com/, along with its corresponding RSA public key. Note that this is not suitable for production data, the RSA private key has been published!

Quickstart

Install from PyPI:

$ pip3 install --upgrade opsep

Encrypt using the testing API token and testing RSA pubkey (no account needed):

from opsep import opsep_hybrid_encrypt, opsep_hybrid_decrypt

# Testing RSA PubKey and OpSep API Server URL (normally saved in your app's config)
RSA_PUBKEY = '-----BEGIN PUBLIC KEY-----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\n6hYJGkAdR0d99DNFlllRm7cCAwEAAQ==\n-----END PUBLIC KEY-----\n'
OPSEP_URL = 'https://test.secondguard.com/'

your_secret = b"attack at dawn!"

# Encrypt locally (symmetrically and asymmetrically) and save the results to your DB:
local_ciphertext, opsep_recovery_instructions = opsep_hybrid_encrypt(
    to_encrypt=your_secret,
    rsa_pubkey=RSA_PUBKEY, 
)

# Asymmetrically decrypt opsep_recovery_instructions (via OpSep's rate-limited API) and use it to symmetrically decrypt local_ciphertext: 
secret_recovered, rate_limit_dict = opsep_hybrid_decrypt( 
    local_ciphertext_to_decrypt=local_ciphertext, 
    opsep_recovery_instructions=opsep_recovery_instructions,
    opsep_url=OPSEP_URL,
)

if your_secret == secret_recovered:
    print("Your secret was recovered: %s" % secret_recovered)

See test_client.py to see how the protocol works.

Audit Log

For audit logging of decryption requests, we recommend storing the sha256 hash digest of the opsep_recovery_instructions (base64 decoded) in an indexed column of your database. This makes it easy to see which records have been decrypted if your servers are breached. See the opsep_hybrid_encrypt_with_auditlog() method with test coverage in test_client.py.

---

Under the Hood

Pull requests with test coverage are welcome!

Check out the code:

$ git checkout git@github.com:opsep/opsep-python.git && cd opsep-python.git

Create & activate a virtual environment, install dependencies & this library

$ python3 -m virtualenv .venv3 && source .venv3/bin/activate && pip3 install -r requirements.txt && pip3 install --editable .

Run tests (requires having previously intalled an --editable local version of this repo):

$ pytest -v
====================================== test session starts ======================================
platform darwin -- Python 3.7.8, pytest-5.4.3, py-1.9.0, pluggy-0.13.1 -- /Users/mflaxman/workspace/secondguard-python/.venv3/bin/python
cachedir: .pytest_cache
rootdir: /Users/mflaxman/workspace/opsep-python
collected 3 items                                                                               

tests/test_client.py::test_opsep_hybrid_encryption_and_decryption PASSED                  [ 33%]
tests/test_pyca.py::test_symmetric PASSED                                                 [ 66%]
tests/test_pyca.py::test_asymmetric PASSED                                                [100%]

To update requirements.txt change requirements.in and then run (requires pip-tools):

$ pip-compile requirements.in

How these insecure testing RSA keys were created:

$ openssl genrsa -out insecureprivkey.pem 4096 && openssl rsa -in insecureprivkey.pem -pubout -out insecurepubkey.crt