Encrypt the string In Typescript And Decrypt In C# using Advanced Encryption Standard Algorithm(AES)

Question

I am having struggle to implement the encryption in typescript and decryption in C#. Before posting question here, I did Google it and find some links but those links are related to JavaScript not a typescript.

Encrypt in javascript and decrypt in C# with AES algorithm

encrypt the text using cryptojs library in angular2

How to import non-core npm modules in Angular 2 e.g. (to use an encryption library)?

I followed the above links, for implementing the encryption/decryption concept in my current application.

This is the code I wrote in myservice.ts

    //import { CryptoJS } from 'node_modules/crypto-js/crypto-js.js';
    //import 'crypto-js';
    import * as CryptoJS from 'crypto-js';


    var key = CryptoJS.enc.Utf8.parse('7061737323313233');
    var iv = CryptoJS.enc.Utf8.parse('7061737323313233');
    var encrypted = CryptoJS.AES.encrypt(CryptoJS.enc.Utf8.parse("It works"), key,
        {
            keySize: 128 / 8,
            iv: iv,
            mode: CryptoJS.mode.CBC,
            padding: CryptoJS.pad.Pkcs7
        });

    var decrypted = CryptoJS.AES.decrypt(encrypted, key, {
        keySize: 128 / 8,
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });

    console.log('Encrypted :' + encrypted);
    console.log('Key :' + encrypted.key);
    console.log('Salt :' + encrypted.salt);
    console.log('iv :' + encrypted.iv);
    console.log('Decrypted : ' + decrypted);
    console.log('utf8 = ' + decrypted.toString(CryptoJS.enc.Utf8));

Before I added the above lines of code in myservice.ts, I added the dependency as "crypto-js": "^3.1.9-1" in package.json file.

After added the above dependency in package.json, then I was restored the packages successfully. But still also CryptoJS shows error in myservice.ts like can not found name as CryptoJS.

Can you please tell me how to import the CryptoJS from node modules and also tell me how to encrypt the string in typescript and decrypt the same string in C# using Advanced Security Algorithm (AES)?

Pradeep

Answer 1

npm instal crypto-js

//Inside imports of your TS file include 
import * as CryptoJS from 'crypto-js';

// Declare this key and iv values in declaration
private key = CryptoJS.enc.Utf8.parse('4512631236589784');
private iv = CryptoJS.enc.Utf8.parse('4512631236589784');

// Methods for the encrypt and decrypt Using AES
encryptUsingAES256() {
    var encrypted = CryptoJS.AES.encrypt(CryptoJS.enc.Utf8.parse(JSON.stringify("Your Json Object data or string")), this.key, {
        keySize: 128 / 8,
        iv: this.iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    console.log('Encrypted :' + encrypted);
    this.decryptUsingAES256(encrypted);
    return encrypted;
}

decryptUsingAES256(decString) {
    var decrypted = CryptoJS.AES.decrypt(decString, this.key, {
        keySize: 128 / 8,
        iv: this.iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    console.log('Decrypted : ' + decrypted);
    console.log('utf8 = ' + decrypted.toString(CryptoJS.enc.Utf8));

}

The C# code to encode or decode is here.

public class encr {
    public static string DecryptStringAES(string cipherText) {
        var keybytes = Encoding.UTF8.GetBytes("4512631236589784");
        var iv = Encoding.UTF8.GetBytes("4512631236589784");

        var encrypted = Convert.FromBase64String(cipherText);
        var decriptedFromJavascript = DecryptStringFromBytes(encrypted, keybytes, iv);
        return decriptedFromJavascript;
    }
    private static string DecryptStringFromBytes(byte[] cipherText, byte[] key, byte[] iv) {
        // Check arguments.
        if (cipherText == null || cipherText.Length <= 0) {
            throw new ArgumentNullException("cipherText");
        }
        if (key == null || key.Length <= 0) {
            throw new ArgumentNullException("key");
        }
        if (iv == null || iv.Length <= 0) {
            throw new ArgumentNullException("key");
        }

        // Declare the string used to hold
        // the decrypted text.
        string plaintext = null;

        // Create an RijndaelManaged object
        // with the specified key and IV.
        using(var rijAlg = new RijndaelManaged()) {
            //Settings
            rijAlg.Mode = CipherMode.CBC;
            rijAlg.Padding = PaddingMode.PKCS7;
            rijAlg.FeedbackSize = 128;

            rijAlg.Key = key;
            rijAlg.IV = iv;

            // Create a decrytor to perform the stream transform.
            var decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV);

            try {
                // Create the streams used for decryption.
                using(var msDecrypt = new MemoryStream(cipherText)) {
                    using(var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read)) {

                        using(var srDecrypt = new StreamReader(csDecrypt)) {
                            // Read the decrypted bytes from the decrypting stream
                            // and place them in a string.
                            plaintext = srDecrypt.ReadToEnd();

                        }

                    }
                }
            } catch {
                plaintext = "keyError";
            }
        }

        return plaintext;
    }

    public static string EncryptStringAES(string plainText) {
        var keybytes = Encoding.UTF8.GetBytes("4512631236589784");
        var iv = Encoding.UTF8.GetBytes("4512631236589784");

        var encryoFromJavascript = EncryptStringToBytes(plainText, keybytes, iv);
        return Convert.ToBase64String(encryoFromJavascript);
    }

    private static byte[] EncryptStringToBytes(string plainText, byte[] key, byte[] iv) {
        // Check arguments.
        if (plainText == null || plainText.Length <= 0) {
            throw new ArgumentNullException("plainText");
        }
        if (key == null || key.Length <= 0) {
            throw new ArgumentNullException("key");
        }
        if (iv == null || iv.Length <= 0) {
            throw new ArgumentNullException("key");
        }
        byte[] encrypted;
        // Create a RijndaelManaged object
        // with the specified key and IV.
        using(var rijAlg = new RijndaelManaged()) {
            rijAlg.Mode = CipherMode.CBC;
            rijAlg.Padding = PaddingMode.PKCS7;
            rijAlg.FeedbackSize = 128;

            rijAlg.Key = key;
            rijAlg.IV = iv;

            // Create a decrytor to perform the stream transform.
            var encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);

            // Create the streams used for encryption.
            using(var msEncrypt = new MemoryStream()) {
                using(var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write)) {
                    using(var swEncrypt = new StreamWriter(csEncrypt)) {
                        //Write all data to the stream.
                        swEncrypt.Write(plainText);
                    }
                    encrypted = msEncrypt.ToArray();
                }
            }
        }
        // Return the encrypted bytes from the memory stream.
        return encrypted;
    }
}

Answer 2

I had a similar issue. I'm using Angular 4/Angular-Cli 1.0.0. What worked for me:

npm install crypto-js --save
npm install @types/crypto-js --save

After these two commands, reference the crypto-js library in the angular-cli.json file, in the "scripts" array. In my case:

"scripts": [
    "../node_modules/crypto-js/crypto-js.js"
  ]

You'll notice that in the node_modules/@types directory, you'll have a crypto-js subdirectory. So put a reference to the node_modules/@types/crypto-js/index.d.ts file in your code, using a triple-slash directive, so the compliler knows that the typings file is necessary to compile that module file:

/// <reference path="relative_path_to_cypto_folder/index.d.ts" />

Alternatively, you can also use "types" attribute instead of "path", since you're referencing a typings definition inside node_modules/@types:

/// <reference types="crypto-js" />

After that you can use your code exactly as it is:

/// <reference types="crypto-js" />

import * as CryptoJS from 'crypto-js';


var key = CryptoJS.enc.Utf8.parse('7061737323313233');
var iv = CryptoJS.enc.Utf8.parse('7061737323313233');
var encrypted = CryptoJS.AES.encrypt(CryptoJS.enc.Utf8.parse("It works"), key,
    {
        keySize: 128 / 8,
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });

var decrypted = CryptoJS.AES.decrypt(encrypted, key, {
    keySize: 128 / 8,
    iv: iv,
    mode: CryptoJS.mode.CBC,
    padding: CryptoJS.pad.Pkcs7
});

console.log('Encrypted :' + encrypted);
console.log('Key :' + encrypted.key);
console.log('Salt :' + encrypted.salt);
console.log('iv :' + encrypted.iv);
console.log('Decrypted : ' + decrypted);
console.log('utf8 = ' + decrypted.toString(CryptoJS.enc.Utf8));