First things first, make sure you have a table in your Xano database where you'll store sensitive data. This table is where we'll be doing our field-level encryption magic.

Next up, figure out which fields in your table need that extra layer of security. For instance, in a users table, you might want to encrypt fields like email or password.

Now, let's generate a strong encryption key. This key is crucial for both encrypting and decrypting your data. Keep it safe and sound!

Generate a key using an encryption tool or library such as OpenSSL.

Inside the Xano Function Stack, create a custom function that uses Xano’s built-in module for encryption. Here's how you can define an encryption function.

// Create a function to encrypt field data
const crypto = require('crypto');
const algorithm = 'aes-256-cbc'; 
const key = Buffer.from('YOUR_ENCRYPTION_KEY_HERE', 'hex'); // Replace with your actual key
const iv = crypto.randomBytes(16);

function encrypt(data) {
  let cipher = crypto.createCipheriv(algorithm, key, iv);
  let encrypted = cipher.update(data, 'utf8', 'hex');
  encrypted += cipher.final('hex');
  return iv.toString('hex') + ':' + encrypted;
}

Now, let's create a decryption function in your Function Stack. This will take encrypted data and turn it back into plaintext.

// Create a function to decrypt field data
function decrypt(data) {
  let textParts = data.split(':');
  let iv = Buffer.from(textParts.shift(), 'hex');
  let encryptedText = Buffer.from(textParts.join(':'), 'hex');
  let decipher = crypto.createDecipheriv(algorithm, key, iv);
  let decrypted = decipher.update(encryptedText, 'hex', 'utf8');
  decrypted += decipher.final('utf8');
  return decrypted;
}

Let's make sure our CRUD operations are using these encryption and decryption functions.

For Create Operation:

Before you insert data into the table, encrypt the fields that need it.

const email = request.body.email;
const encryptedEmail = encrypt(email);

// Proceed with inserting encryptedEmail into the database

For Read Operation:

When you retrieve data from the database, decrypt the fields before sending them to the client.

const encryptedEmail = retrievedData.email;
const decryptedEmail = decrypt(encryptedEmail);

// Proceed with using decryptedEmail as needed

Make sure the encryption functions are used correctly when updating or deleting records.

For Update Operation:

When updating, encrypt the sensitive fields before saving the record.

const newEmail = request.body.email;
const encryptedEmail = encrypt(newEmail);

// Proceed with updating the database record with encryptedEmail

For Delete Operation:

Usually, no changes are needed for delete operations since they typically reference the primary key.

Finally, ensure that your encryption key is securely stored and managed. Use environment variables or a secrets management service to handle the keys.

Use environment variables to store your encryption key:
process.env.ENCRYPTION_KEY

And there you have it! That's how you can implement field-level encryption in Xano. Keep those keys safe and make sure your CRUD operations are all set to handle encrypted data.