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  1. @ufologist ufologist created this gist May 15, 2013.
    101 changes: 101 additions & 0 deletions CryptoJS-DES.html
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    <!-- test pass with CryptoJS v3.1.2 -->
    <script src="rollups/tripledes.js"></script>
    <script src="components/mode-ecb.js"></script>
    <script>
    /**
    * Encrypt message by DES in ECB mode and Pkcs7 padding scheme
    *
    * NOTE: DES is weak, please use 3DES(Triple DES) or AES
    *
    * @param {String} message
    * @param {String} key
    * @return {String} ciphertext(base64 string)
    *
    * @author Sun
    * @version 2013-5-15
    *
    * @see <a href="https://groups.google.com/d/msg/crypto-js/I378fq3esK8/HZ2P2Xtuzk8J">des encrypion: js encrypted value does not match the java encrypted value</a>
    * In cryptoJS you have to convert the key to hex
    * and useit as word just like above (otherwise it will be considered as passphrase)
    *
    * @see <a href="http://stackoverflow.com/questions/12894722/c-sharp-and-java-des-encryption-value-are-not-identical">C# and Java DES Encryption value are not identical</a>
    * SunJCE provider uses ECB as the default mode,
    * and PKCS5Padding as the default padding scheme for DES.(JCA Doc)
    * This means that in the case of the SunJCE provider,
    * Cipher c1 = Cipher.getInstance("DES/ECB/PKCS5Padding");
    * and
    * Cipher c1 = Cipher.getInstance("DES");
    * are equivalent statements.
    *
    * @see <a href="http://stackoverflow.com/questions/10193567/java-security-nosuchalgorithmexception-cannot-find-any-provider-supporting-aes">java.security.NoSuchAlgorithmException: Cannot find any provider supporting AES/ECB/PKCS7PADDING</a>
    * I will point out that PKCS#5 and PKCS#7 actually specify exactly
    * the same type of padding (they are the same!),
    * but it's called #5 when used in this context. :)
    */
    function encryptByDES(message, key) {
    // For the key, when you pass a string,
    // it's treated as a passphrase and used to derive an actual key and IV.
    // Or you can pass a WordArray that represents the actual key.
    // If you pass the actual key, you must also pass the actual IV.
    var keyHex = CryptoJS.enc.Utf8.parse(key);
    // console.log(CryptoJS.enc.Utf8.stringify(keyHex), CryptoJS.enc.Hex.stringify(keyHex));
    // console.log(CryptoJS.enc.Hex.parse(CryptoJS.enc.Utf8.parse(key).toString(CryptoJS.enc.Hex)));

    // CryptoJS use CBC as the default mode, and Pkcs7 as the default padding scheme
    var encrypted = CryptoJS.DES.encrypt(message, keyHex, {
    mode: CryptoJS.mode.ECB,
    padding: CryptoJS.pad.Pkcs7
    });
    // decrypt encrypt result
    // var decrypted = CryptoJS.DES.decrypt(encrypted, keyHex, {
    // mode: CryptoJS.mode.ECB,
    // padding: CryptoJS.pad.Pkcs7
    // });
    // console.log(decrypted.toString(CryptoJS.enc.Utf8));

    // when mode is CryptoJS.mode.CBC (default mode), you must set iv param
    // var iv = 'inputvec';
    // var ivHex = CryptoJS.enc.Hex.parse(CryptoJS.enc.Utf8.parse(iv).toString(CryptoJS.enc.Hex));
    // var encrypted = CryptoJS.DES.encrypt(message, keyHex, { iv: ivHex, mode: CryptoJS.mode.CBC });
    // var decrypted = CryptoJS.DES.decrypt(encrypted, keyHex, { iv: ivHex, mode: CryptoJS.mode.CBC });

    // console.log('encrypted.toString() -> base64(ciphertext) :', encrypted.toString());
    // console.log('base64(ciphertext) <- encrypted.toString():', encrypted.ciphertext.toString(CryptoJS.enc.Base64));
    // console.log('ciphertext.toString() -> ciphertext hex :', encrypted.ciphertext.toString());
    return encrypted.toString();
    }

    /**
    * Decrypt ciphertext by DES in ECB mode and Pkcs7 padding scheme
    *
    * @param {String} ciphertext(base64 string)
    * @param {String} key
    * @return {String} plaintext
    *
    * @author Sun
    * @version 2013-5-15
    */
    function decryptByDES(ciphertext, key) {
    var keyHex = CryptoJS.enc.Utf8.parse(key);

    // direct decrypt ciphertext
    var decrypted = CryptoJS.DES.decrypt({
    ciphertext: CryptoJS.enc.Base64.parse(ciphertext)
    }, keyHex, {
    mode: CryptoJS.mode.ECB,
    padding: CryptoJS.pad.Pkcs7
    });

    return decrypted.toString(CryptoJS.enc.Utf8);
    }

    var message = 'Message';
    var key = 'abcd1234';

    var ciphertext = encryptByDES(message, key);
    // ciphertext: 8dKft9vkZ4I=
    console.info('ciphertext:', ciphertext);
    var plaintext = decryptByDES(ciphertext, key);
    // plaintext : Message
    console.info('plaintext :', plaintext);
    </script>