Implementing data encryption with SQL ORM

29 Sep 2023

In today’s digital era, data security is of paramount importance. As developers, we must ensure that sensitive data stored in databases is protected from unauthorized access. One effective way to achieve this is through data encryption. In this blog post, we will explore how to implement data encryption using SQL ORM.

What is Data Encryption?

Data encryption is the process of converting data into a form that is unreadable or meaningless to anyone without the access key or secret decryption method. Encryption helps protect sensitive information from unauthorized access and ensures data confidentiality.

SQL ORM and Encryption

SQL ORM (Object-Relational Mapping) is a technique that allows developers to interact with databases using high-level programming constructs instead of writing raw SQL queries. Many popular programming languages such as Python, Java, and Ruby provide ORM frameworks to simplify database operations.

To implement data encryption with SQL ORM, we need to follow these steps:

Setting up database connection: Establish a connection to the database using the ORM framework of your choice. This may involve configuring connection parameters such as host, port, username, and password.
Define encryption function: Write or utilize a cryptographic library to define a function that will encrypt the sensitive data before storing it in the database. This function will take the plain text data as input and return the encrypted result.

Example code using Python and the cryptography library:
```
from cryptography.fernet import Fernet
key = Fernet.generate_key()
cipher_suite = Fernet(key)

def encrypt(data):
    cipher_text = cipher_suite.encrypt(data.encode())
    return cipher_text
```
Update database models: Modify the database models or schemas to include a new column for storing the encrypted data. This column should have a suitable data type, such as VARBINARY or BLOB, to store binary data.

Encrypt data before saving: Before saving sensitive data to the database, invoke the encryption function defined in step 2 to encrypt the plain text data.

Example code using SQLAlchemy ORM in Python:

from sqlalchemy import Column, String
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

class User(Base):
    __tablename__ = 'users'
    id = Column(Integer, primary_key=True)
    username = Column(String(50))
    password = Column(VARBINARY(128))

    def set_password(self, password):
        encrypted_password = encrypt(password)
        self.password = encrypted_password

In this code snippet, the set_password method encrypts the password before saving it to the password column.

Decrypt data when retrieving: When retrieving data from the database, you need to decrypt the encrypted data using the decryption method or function.

Example code:

def decrypt(cipher_text):
    plain_text = cipher_suite.decrypt(cipher_text)
    return plain_text.decode()

# Retrieving and decrypting password using SQLAlchemy ORM
user = session.query(User).filter_by(id=1).first()
decrypted_password = decrypt(user.password)

Here, the decrypt function decrypts the stored password retrieved from the User model.

Conclusion

Implementing data encryption with SQL ORM is a powerful technique to protect sensitive data stored in databases. By following the steps outlined in this blog post, you can enhance the security of your application and ensure the confidentiality of your users’ information. With data encryption in place, you can have peace of mind knowing that your database is secure from unauthorized access.

#dataencryption #security