mastercard-api-core/lib/security/mpqrmes/mes-cryptography.js

Core functionality for MasterCard API

var FieldLevelEncryption = require('../fle/field-level-encryption');
var DataEncoding = require('../util/data-encoding');
var utils = require('../../utils');

var config = {
    triggeringEndPath: [
        '/mes/api/v1/merchants/.*/transactions',
        '/paygo/api/v1/merchants/.*/transactions',
        '/mpqr-mes/api/v1/merchants/.*/transactions',
        '/mpqr-paygo/api/v1/merchants/.*/transactions',

        '/mes/api/v1/transactions',
        '/paygo/api/v1/transactions',
        '/mpqr-mes/api/v1/transactions',
        '/mpqr-paygo/api/v1/transactions',
    ],

    fieldsToEncrypt: [],
    fieldsToDecrypt: ['items', 'data.extraData'],

    symmetricAlgorithm: 'AES-CBC',
    symmetricCipher: 'AES',
    symmetricKeysize: 128,

    asymmetricCipher: 'RSA-OAEP',
    oaepHashingAlgorithm: 'SHA-512',
    oaepHashingAlgorithmFieldName: 'oaepHashingAlgorithm',

    publicKeyFingerprintHashing: 'SHA-256',
    publicKeyFingerprintFieldName: 'publicKeyFingerprint',

    ivFieldName: 'iv',
    encryptedKeyFieldName: 'encryptedKey',
    dataEncoding: DataEncoding.BASE64,
}

function MESCryptography(opts) {
    FieldLevelEncryption.call(this, {
        publicCertificatePath: opts.publicCertificatePath,
        keystorePath: opts.keystorePath,
        privateKeyAlias: opts.privateKeyAlias,
        privateKeyPassword: opts.privateKeyPassword,
        publicKeyFingerprint: opts.publicKeyFingerprint,
        privateKeyPath: opts.privateKeyPath,
        config: config,
    });
}

MESCryptography.prototype = Object.create(FieldLevelEncryption.prototype);
MESCryptography.prototype.constructor = MESCryptography;

MESCryptography.prototype.encrypt = function(requestObj) {
    if (this.publicCertificate == null || requestObj == null) {
        return requestObj;
    }

    var length = config.fieldsToEncrypt.length;

    for (var i = 0; i < length; i++) {
        var fieldToEncrypt = config.fieldsToEncrypt[i];

        var objectDetail = utils.get(requestObj, fieldToEncrypt);
        if (objectDetail == null) {
            continue;
        }

        var payload = JSON.stringify(objectDetail.object);
        const encrypted = this.encryptPlainText(payload);

        var parent = objectDetail.parent;
        var objectFieldName = objectDetail.objectFieldName;

        parent[objectFieldName] = encrypted.cipherText;
        parent[config.ivFieldName] = encrypted.iv;
        parent[config.encryptedKeyFieldName] = encrypted.encryptedKey;

        if (config.publicKeyFingerprintFieldName != null) {
            parent[config.publicKeyFingerprintFieldName] = encrypted.publicKeyFingerprint;
        }
        if (config.oaepHashingAlgorithmFieldName != null) {
            parent[config.oaepHashingAlgorithmFieldName] = encrypted.oaepHashingAlgorithm;
        }
    }

    return requestObj;
}

MESCryptography.prototype.decrypt = function(responseObj) {
    if (this.privateKey == null || responseObj == null) {
        return responseObj;
    }

    var length = config.fieldsToDecrypt.length;

    for (var i = 0; i < length; i++) {
        var fieldToDecrypt = config.fieldsToDecrypt[i];

        var objectDetail = utils.get(responseObj, fieldToDecrypt);
        if (objectDetail == null) {
            continue;
        }

        var parent = objectDetail.parent;
        var objectFieldName = objectDetail.objectFieldName;

        // read encrypted key
        var encryptedKey = parent[config.encryptedKeyFieldName];
        delete parent[config.encryptedKeyFieldName];

        var oaepHashingAlgorithm = parent[config.oaepHashingAlgorithmFieldName];
        if (oaepHashingAlgorithm != null) {
            delete parent[config.oaepHashingAlgorithmFieldName];
        }

        // remove public key fingerprint field
        delete parent[config.publicKeyFingerprintFieldName];

        // read iv
        var ivString = parent[config.ivFieldName];
        delete parent[config.ivFieldName];

        // decrypt the data
        var decryptedData = this.decryptCipherText(objectDetail.object, ivString, encryptedKey, oaepHashingAlgorithm);

        parent[objectFieldName] = JSON.parse(decryptedData);
    }

    return responseObj;
}

module.exports = MESCryptography;