From 6dfb096a5e5af930041541fe2a4d6aa41135b2ab Mon Sep 17 00:00:00 2001
From: Jon Herron <jon.herron@yahoo.com>
Date: Mon, 6 Mar 2023 19:07:08 -0500
Subject: [PATCH] Encrypt/decrypt secrets

---
 .../src/spiffworkflow_backend/__init__.py     |  6 +++
 .../services/secret_service.py                | 45 ++++++++++---------
 2 files changed, 29 insertions(+), 22 deletions(-)

diff --git a/spiffworkflow-backend/src/spiffworkflow_backend/__init__.py b/spiffworkflow-backend/src/spiffworkflow_backend/__init__.py
index 0fc3d049..f84c79aa 100644
--- a/spiffworkflow-backend/src/spiffworkflow_backend/__init__.py
+++ b/spiffworkflow-backend/src/spiffworkflow_backend/__init__.py
@@ -13,6 +13,7 @@ from apscheduler.schedulers.base import BaseScheduler  # type: ignore
 from flask.json.provider import DefaultJSONProvider
 from flask_cors import CORS  # type: ignore
 from flask_mail import Mail  # type: ignore
+from flask_simple_crypt import SimpleCrypt
 from werkzeug.exceptions import NotFound
 
 import spiffworkflow_backend.load_database_models  # noqa: F401
@@ -133,6 +134,11 @@ def create_app() -> flask.app.Flask:
 
     configure_sentry(app)
 
+    cipher = SimpleCrypt()
+    app.config['FSC_EXPANSION_COUNT'] = 2048
+    cipher.init_app(app)
+    app.config['CIPHER'] = cipher
+
     app.before_request(verify_token)
     app.before_request(AuthorizationService.check_for_permission)
     app.after_request(set_new_access_token_in_cookie)
diff --git a/spiffworkflow-backend/src/spiffworkflow_backend/services/secret_service.py b/spiffworkflow-backend/src/spiffworkflow_backend/services/secret_service.py
index f34be93d..8124f706 100644
--- a/spiffworkflow-backend/src/spiffworkflow_backend/services/secret_service.py
+++ b/spiffworkflow-backend/src/spiffworkflow_backend/services/secret_service.py
@@ -1,41 +1,39 @@
 """Secret_service."""
 from typing import Optional
 
+from flask import current_app
+from flask_simple_crypt import SimpleCrypt
+
 from spiffworkflow_backend.exceptions.api_error import ApiError
 from spiffworkflow_backend.models.db import db
 from spiffworkflow_backend.models.secret_model import SecretModel
 
-# from cryptography.fernet import Fernet
-#
-#
-# class EncryptionService:
-#     key = Fernet.generate_key()  # this is your "password"
-#     cipher_suite = Fernet(key)
-#     encoded_text = cipher_suite.encrypt(b"Hello stackoverflow!")
-#     decoded_text = cipher_suite.decrypt(encoded_text)
-
 
 class SecretService:
     """SecretService."""
 
-    # def encrypt_key(self, plain_key: str) -> str:
-    #     """Encrypt_key."""
-    #     # flask_secret = current_app.secret_key
-    #     # print("encrypt_key")
-    #     ...
+    CIPHER_ENCODING = "ascii"
 
-    # def decrypt_key(self, encrypted_key: str) -> str:
-    #     """Decrypt key."""
-    #     ...
+    @classmethod
+    def _encrypt(cls, value: str) -> str:
+        encrypted_bytes = current_app.config["CIPHER"].encrypt(value)
+        return encrypted_bytes.decode(cls.CIPHER_ENCODING)
 
-    @staticmethod
+    @classmethod
+    def _decrypt(cls, value: str) -> str:
+        bytes_to_decrypt = bytes(value, cls.CIPHER_ENCODING)
+        decrypted_bytes = current_app.config["CIPHER"].decrypt(bytes_to_decrypt)
+        return decrypted_bytes.decode(cls.CIPHER_ENCODING)
+
+    @classmethod
     def add_secret(
+        cls,
         key: str,
         value: str,
         user_id: int,
     ) -> SecretModel:
         """Add_secret."""
-        # encrypted_key = self.encrypt_key(key)
+        value = cls._encrypt(value)
         secret_model = SecretModel(key=key, value=value, user_id=user_id)
         db.session.add(secret_model)
         try:
@@ -50,11 +48,12 @@ class SecretService:
             ) from e
         return secret_model
 
-    @staticmethod
-    def get_secret(key: str) -> SecretModel:
+    @classmethod
+    def get_secret(cls, key: str) -> SecretModel:
         """Get_secret."""
         secret = db.session.query(SecretModel).filter(SecretModel.key == key).first()
         if isinstance(secret, SecretModel):
+            secret.value = cls._decrypt(secret.value)
             return secret
         else:
             raise ApiError(
@@ -62,14 +61,16 @@ class SecretService:
                 message=f"Unable to locate a secret with the name: {key}. ",
             )
 
-    @staticmethod
+    @classmethod
     def update_secret(
+        cls,
         key: str,
         value: str,
         user_id: Optional[int] = None,
         create_if_not_exists: Optional[bool] = False,
     ) -> None:
         """Does this pass pre commit?"""
+        value = cls._encrypt(value)
         secret_model = SecretModel.query.filter(SecretModel.key == key).first()
         if secret_model:
             secret_model.value = value