Encrypt decrypt in CI4 - CodeIgniter 4

To pass an encrypted value in a URL and decrypt it in CodeIgniter 4 (CI4), you can use the Encryption library provided by CI4. Here’s how to implement this:

1. Configure Encryption in CI4

Ensure that the encryption service is properly set up. Open the app/Config/Encryption.php file and configure it:

<?php

namespace Config;

use CodeIgniter\Config\BaseConfig;

class Encryption extends BaseConfig
{
    public $key = 'your-encryption-key'; // Replace with a random key
    public $driver = 'OpenSSL';         // Use OpenSSL for encryption
}

<?php

namespace Config;

use CodeIgniter\Config\BaseConfig;

class Encryption extends BaseConfig

{

public $key = 'your-encryption-key'; // Replace with a random key

public $driver = 'OpenSSL'; // Use OpenSSL for encryption

}

Replace your-encryption-key with a strong random key. You can generate one using bin2hex(random_bytes(32)) in PHP.

2. Encrypt the Value

Use CI4’s encrypter() helper to encrypt the value before adding it to the URL:

use CodeIgniter\Encryption\Encryption;

$encrypter = \Config\Services::encrypter();

// The value to encrypt
$data = 'your-value-to-encrypt';

// Encrypt the value
$encryptedValue = base64_encode($encrypter->encrypt($data));

// Pass the encrypted value in the URL
$url = base_url('your-controller/your-method/' . $encryptedValue);

use CodeIgniter\Encryption\Encryption;

$encrypter = \Config\Services::encrypter();

// The value to encrypt

$data = 'your-value-to-encrypt';

// Encrypt the value

$encryptedValue = base64_encode($encrypter->encrypt($data));

// Pass the encrypted value in the URL

$url = base_url('your-controller/your-method/' . $encryptedValue);

3. Decrypt the Value

Retrieve and decrypt the value in your controller:

public function yourMethod($encryptedValue)
{
    $encrypter = \Config\Services::encrypter();

    // Decode and decrypt the value
    try {
        $decryptedValue = $encrypter->decrypt(base64_decode($encryptedValue));
        echo 'Decrypted Value: ' . $decryptedValue;
    } catch (\Exception $e) {
        // Handle errors (e.g., invalid encryption or tampered data)
        echo 'Decryption failed: ' . $e->getMessage();
    }
}

public function yourMethod($encryptedValue)

{

$encrypter = \Config\Services::encrypter();

// Decode and decrypt the value

try {

$decryptedValue = $encrypter->decrypt(base64_decode($encryptedValue));

echo 'Decrypted Value: ' . $decryptedValue;

} catch (\Exception $e) {

// Handle errors (e.g., invalid encryption or tampered data)

echo 'Decryption failed: ' . $e->getMessage();

}

4. Example Flow

Encrypt and Generate URL:

$data = '12345';
$encryptedValue = base64_encode($encrypter->encrypt($data));
echo base_url('example/decrypt/' . $encryptedValue);

$data = '12345';

$encryptedValue = base64_encode($encrypter->encrypt($data));

echo base_url('example/decrypt/' . $encryptedValue);

Decrypt in Controller:

public function decrypt($encryptedValue)
{
    $encrypter = \Config\Services::encrypter();
    $decryptedValue = $encrypter->decrypt(base64_decode($encryptedValue));
    echo 'Decrypted Value: ' . $decryptedValue;
}

public function decrypt($encryptedValue)

{

$encrypter = \Config\Services::encrypter();

$decryptedValue = $encrypter->decrypt(base64_decode($encryptedValue));

echo 'Decrypted Value: ' . $decryptedValue;

}