Card Return

This functionality allows the site to retrieve the card used in a transaction, this information is useful for dispersion actions or internal services of the merchant that require it.

To return the encrypted card, we currently offer the following algorithms along with their respective key sizes:

• aes-128-cbc (16)
• aes-192-cbc (24)
• aes-256-cbc (32)
• des-ede3-cbc (24)

The PAN field is encoded in BASE64 and is the concatenation of the encrypted card plus the initialization vector (IV), which is generated with the same key size used for encryption.

{
  "additional": {
    "PAN": "klbrfTC1ol9BV7sFP9bw66nLH77QMYAA3GRZrzjutciFv/gqg9xZs8n7gPNxRRsl"
  }
}

The encryption key used in this example with the "aes-128-cbc" algorithm comes from the site's configuration and is provided during the implementation with the payment gateway. In this case, the key is oX1R9A2DoxEziVqT.

<?php
// Initial values
$PAN = 'klbrfTC1ol9BV7sFP9bw66nLH77QMYAA3GRZrzjutciFv/gqg9xZs8n7gPNxRRsl';
$key = 'oX1R9A2DoxEziVqT';
$algorithm = 'aes-128-cbc';
$iv_size = strlen($key);

// Convert from BASE64 to binary
$encoded = base64_decode($PAN);

// Extract the IV and the encrypted card
$iv = mb_substr($encoded, -$iv_size, null, '8bit');
$encrypted = mb_substr($encoded, 0, -$iv_size, '8bit');

// Proceed to decrypt the card
$cardNumber = openssl_decrypt($encrypted, $algorithm, $key, OPENSSL_RAW_DATA, $iv);
?>

FAQs