(Node.js) RSA Encrypt and Decrypt Credit Card Numbers

Node.js sample code to RSA public-key encrypt and decrypt credit card numbers. The RSA key is loaded from an unencrypted PKCS8 file. Chilkat provides many ways of setting the key -- loading from both encrypted and unencrypted PEM, PKCS8, DER, PVK, etc. Keys may be loaded from files or in-memory representations. (The RSA component also provides the ability to generate RSA keys.)

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    var rsa = new chilkat.Rsa();

    var key = new chilkat.PrivateKey();

    // Load an RSA private key from a file:
    var success = key.LoadAnyFormatFile("rsaPrivateKey.key","");
    if (success !== true) {
        console.log(key.LastErrorText);
        return;
    }

    // Get the key as XML:
    var keyXml;
    keyXml = key.GetXml();

    // We'll encrypt with the public key and decrypt with the private
    // key.  (It's also possible to do the reverse.)
    // Note: An RSA private key is composed of different parts internally: modulus, exponent, P, Q, etc.
    // An RSA public-key is a sub-set of the private key.
    // Therefore, when you have a private key, you really have
    // both public and private keys.
    success = rsa.ImportPublicKey(keyXml);
    if (success !== true) {
        console.log(rsa.LastErrorText);
        return;
    }

    // Encrypt a VISA credit card number:
    // 1234-5678-0000-9999
    var ccNumber = "1234567800009999";

    var usePrivateKey = false;
    rsa.EncodingMode = "base64";
    var encryptedStr = rsa.EncryptStringENC(ccNumber,usePrivateKey);
    console.log("Encrypted:");
    console.log(encryptedStr);

    // Now decrypt:
    var rsaDecryptor = new chilkat.Rsa();

    rsaDecryptor.EncodingMode = "base64";
    success = rsaDecryptor.ImportPrivateKey(keyXml);

    usePrivateKey = true;
    var decryptedStr = rsaDecryptor.DecryptStringENC(encryptedStr,usePrivateKey);

    console.log("Decrypted:");
    console.log(decryptedStr);

    // Important: RSA encryption should only be used to encrypt small amounts of data.
    // It is typically used for encrypting symmetric encryption
    // keys such that a symmetric encryption algorithm, such as 
    // AES is then used to encrypt/decrypt bulk data

}

chilkatExample();