Encrypt/decrypt with two different keys - javascript

My code
I'm encrypting a string with two different keys with CryptoJS:
var password = "testpassword";
var serverkey = "randomkey";
var text = document.getElementById("new_note").value;
var encrypted1 = CryptoJS.AES.encrypt(text, password);
encrypted1 = encrypted1.toString();
var encrypted = CryptoJS.AES.encrypt(encrypted1,serverkey);
And trying to decrypt it with this code:
var password = "testpassword";
var serverkey = "randomkey";
var encrypted_text = localStorage.getItem("encrypted");
var decrypted1 = CryptoJS.AES.decrypt(encrypted_text,serverkey);
decrypted1 = decrypted.toString();
var decrypted = CryptoJS.AES.decrypt(decrypted1,password);
decrypted = decrypted.toString(CryptoJS.enc.Utf8);
document.getElementById("decrypted").innerHTML = decrypted;
What isn't working
While the encryption seems to work fine, when I try to convert decrypted1 to a string in order to decrypt it the second time, I get Cannot read property 'toString' of undefined on the chrome console. This should mean that the first decryption process returns an empty string.
My question
How can I fix this problem?

There is a typo in your variable names. Check where you define decrypted and where you use it. You meant to use decrypted1.
Additionally, you have a problem with the encoding. The first decrypted1.toString(); will encode the string into Hex, but earlier you called encrypted1.toString(); which does not encode to Hex, but a special Base64 encoding (OpenSSL compatible). You will need to encode to UTF-8 in order to get to the same encoding that you had before during encryption.
Here is the working code:
document.getElementById("enc_button").onclick = function(){
var password = "testpassword";
var serverkey = "randomkey";
var text = document.getElementById("new_note").value;
var encrypted1 = CryptoJS.AES.encrypt(text, password);
encrypted1 = encrypted1.toString();
var encrypted = CryptoJS.AES.encrypt(encrypted1, serverkey);
var decrypted1 = CryptoJS.AES.decrypt(encrypted,serverkey);
decrypted1 = decrypted1.toString(CryptoJS.enc.Utf8);
var decrypted = CryptoJS.AES.decrypt(decrypted1,password);
decrypted = decrypted.toString(CryptoJS.enc.Utf8);
document.getElementById("decrypted").innerHTML = decrypted;
}
<script src="https://cdn.rawgit.com/CryptoStore/crypto-js/3.1.2/build/rollups/aes.js"></script>
<div id="decrypted">Please wait...</div>
<div>
Insert new note:
<input type="text" id="new_note">
<input type="button" id="enc_button" value="Encrypt & Decrypt">
</div>

It looks like decripted IS empty.
you have initialized decripted1
var decrypted1 = CryptoJS.AES.decrypt(encrypted_text,serverkey);
and then tryed to "toString()" the uninitialized decrypted var
decrypted1 = decrypted.toString();
Although I think you don't need this line... (?).

Related

Similar Encrypt code in javascript as in C#

I use some remote api, they use such C# code:
SHA256Managed sha256Managed = new SHA256Managed();
byte[] passwordSaltBytes = Encoding.Unicode.GetBytes("zda");
byte[] hash = sha256Managed.ComputeHash(passwordSaltBytes);
string result = Convert.ToBase64String(hash);
Console.WriteLine("result = " + result); // result = NUbWRkT8QfzmDt/2kWaikNOZUXIDt7KKRghv0rTGIp4=
I need to get the same result in my javascript frontend code. Does somebody can help with such problem?
The answer is:
var utf8arr = CryptoJS.enc.Utf16LE.parse("zda");
var hash = CryptoJS.SHA256(utf8arr);
var base64 = CryptoJS.enc.Base64.stringify(hash);
console.log(base64);
Not quite obvious, but Unicode in C# is using UTF-16LE enconding.
So you can use CryptoJS to achieve the same result:
var utf16 = CryptoJS.enc.Utf16LE.parse("zda");
var hash = CryptoJS.SHA256(utf16);
var base64 = CryptoJS.enc.Base64.stringify(hash);
console.log(base64);

Html textarea changing the value of a encoded javascript string

I'm working on this Encryption Cipher using CryptoJS for people who want to encrypt their messages. Unfortunately, I've run into a problem decrypting any messages that is encrypted using "NoPadding" padding. After hours and hours of testing the program for bugs, I finally found out what the problem was. I turns out that, when I append the encrypted javascript string into the HTML textarea, it changed the value of the string. Therefore, when I tried to decrypt the value from the textarea, it didn't work.
<textarea id="textarea"></textarea>
<button onclick="encrypting_without_textarea()">encrypting without textarea</button>
<button onclick="encrypting_with_textarea()">encrypting with textarea</button>
HTML
function encrypting_without_textarea(){
var textarea_element = document.getElementById("textarea");
var encryptionKey = "fkjasdlfkdsanfknlasknflsjkanflnasjkfnjknskjnfnlsnf";
var key = CryptoJS.enc.Hex.stringify(encryptionKey);
var value = "Multi-stability is the tendency of ambiguous perceptual experiences to move unstably back and forth between alternative interpretations. Some objects can be perceived in more than one way. An example from below in the section of figure/ground.";
var paddingObject = CryptoJS.pad.NoPadding;
var encrypted = CryptoJS.AES.encrypt(value, key, {mode:CryptoJS.mode.ECB, padding:paddingObject});
var decrypted = CryptoJS.AES.decrypt(encrypted, key, {mode:CryptoJS.mode.ECB, padding:paddingObject});
var msg = decrypted.toString(CryptoJS.enc.Utf8);
alert(msg);
}
The one above is decrypted straight from the encrypted message and it works, and the one below is decrypted with the value from from the textarea but it returns an error.
function encrypting_with_textarea(){
var textarea_element = document.getElementById("textarea");
var encryptionKey = "fkjasdlfkdsanfknlasknflsjkanflnasjkfnjknskjnfnlsnf";
var key = CryptoJS.enc.Hex.stringify(encryptionKey);
var value = "Multi-stability is the tendency of ambiguous perceptual experiences to move unstably back and forth between alternative interpretations. Some objects can be perceived in more than one way. An example from below in the section of figure/ground.";
var paddingObject = CryptoJS.pad.NoPadding;
var encrypted = CryptoJS.AES.encrypt(value, key, {mode:CryptoJS.mode.ECB, padding:paddingObject});
textarea_element.value = encrypted;
var decrypted = CryptoJS.AES.decrypt(textarea_element.value, key, {mode:CryptoJS.mode.ECB, padding:paddingObject});
var msg = decrypted.toString(CryptoJS.enc.Utf8);
alert(msg);
//Error: Malformed UTF-8 data
}
Here is the plnkr link. I understand that the value append to the textarea has change, but how? And, how do I change/encode the string so that the code can be display in the textarea and copy so that the message can be paste/decode with out it being corrupted. I'm open to any solutions, simpler the better?

SJCL not concatenating bit arrays

I am trying to use RNCryptor-JS which uses SJCL but for some reason, SJCL bit array concatenation does not seem to work.
var SALT_SIZE = 64/8;
var plaintext = "Hello, World!";
var password = "myPassword";
function keyForPassword(password, salt){
// Using CryptoJS for pbkdf2, aes, sha256, and random word arrays
var pbkdf2_key = CryptoJS.PBKDF2(
password,
salt,
{
keySize: 256/32,
iterations: 1000,
hasher: CryptoJS.algo.SHA256
}
);
return pbkdf2_key;
}
var encryption_salt = CryptoJS.lib.WordArray.random(SALT_SIZE);
var encryption_key = keyForPassword(password, encryption_salt);
var hmac_salt = CryptoJS.lib.WordArray.random(SALT_SIZE);
var hmac_key = keyForPassword(password, hmac_salt);
var iv = CryptoJS.lib.WordArray.random(128/8);
var version = sjcl.codec.hex.toBits("03");
var options = sjcl.codec.hex.toBits("01");
var message = sjcl.bitArray.concat(version, iv);
message = sjcl.bitArray.concat(message, encryption_salt);
message = sjcl.bitArray.concat(message, hmac_salt);
message = sjcl.bitArray.concat(message, iv);
// Progressive cipher
var aesEncryptor = CryptoJS.algo.AES.createEncryptor(encryption_key, {iv: iv});
var ciphertext = aesEncryptor.process(plaintext);
message = sjcl.bitArray.concat(message, ciphertext);
var hmac = new sjcl.misc.hmac(hmac_key).encrypt(message);
var encrypted_data = sjcl.bitArray.concat(message, hmac);
var output = sjcl.codec.hex.fromBits(encrypted_data);
console.log(output);
When I log the output of message after the first set of sjcl.bitArray.concat is done, all that returns is the first concatenation of version and iv. The final hex output is just that first concatenation and hmac concatenated. This reinforces my suspicion that it might be CryptoJS's fault because the output concatenation works and is between two sjcl variables.
I tried using SJCL random bit arrays but had some trouble. SJCL's generator, prng, did not work when using
new sjcl.prng.randomWords(32/4);
or
new sjcl.prng(32/4);
And sjcl.random.randomWords does not seem to work anymore.
CryptoJS (WordArray) and SJCL (bitArray) have different internal representations of data. You can't simply concatenate them.
The easiest way would be probably to encode it into an intermediate format such as Hex and let the other side decode into its internal format:
message = sjcl.bitArray.concat(version, sjcl.codec.hex.toBits(iv.toString()));
WordArray#toString() automatically uses Hex encoding. You would have to do this for all lines, but this is a little overkill, since you can concatenate Hex strings as strings:
message = sjcl.codec.hex.toBits("03" + iv + encryption_salt + hmac_salt + iv);
This should work as expected, because adding a WordArray such as iv to a string automatically calls its toString() function which in turn produces a big-endian hex-encoded string.
I wonder why you're using iv twice. Perhaps you meant options on one of them.
What needs to change:
function convert(wordArray){
return sjcl.codec.hex.toBits(wordArray.toString());
}
var message = "0301" + encryption_salt + hmac_salt + iv;
var ciphertext = CryptoJS.AES.encrypt(plaintext, encryption_key, {iv: iv}).ciphertext;
message += ciphertext;
message = sjcl.codec.hex.toBits(message);
var hmac = new sjcl.misc.hmac(convert(hmac_key)).encrypt(message);
var encrypted_data = sjcl.bitArray.concat(message, hmac);
var output = sjcl.codec.hex.fromBits(encrypted_data);
console.log(output);

SHA512 not the same in CryptoJS and Closure

I have some troubles with a simple crypto-challenge.
I want to do following:
getting a url-encoded and base64-encoded value
do url-decoding
do base64-decoding
hash with Sha512
When working with CryptoJS, i use following code:
var parameter = "Akuwnm2318kwioasdjlnmn";
var urlDecoded = decodeURIComponent(parameter);
var base64Decoded = CryptoJS.enc.Base64.parse(urlDecoded);
var hashed = CryptoJS.SHA512(base64Decoded).toString(CryptoJS.enc.Base64);
//hashed = "UxupkI5+dkhUorQ+K3+Tqct1WNUkj3I6N76g82CbNQ0EAH/nWjqi9CW5Qec1vq/qakNIYeXeqiAPOVAVkzf9mA=="/eWTS2lUgCEe6NJDXhNfYvXMRQDvH6k2PHVmy6LJS7RloVvcQcpVjRNVU5lJpAg=="
When working with Closure, i use following code:
var parameter = "Akuwnm2318kwioasdjlnmn";
var urlDecoded = decodeURIComponent(parameter);
var byteArray = goog.crypt.base64.decodeStringToByteArray(urlDecoded);
var base64Decoded = goog.crypt.byteArrayToHex(byteArray);
var sha512 = new goog.crypt.Sha512();
sha512.update(base64Decoded);
var hashed = sha512.digest();
hashed = goog.crypt.byteArrayToHex(hashed);
//hashed = "bc2a878edfffb0937fbc6c0f9dbc9566edc59b74080d68d4c8bdfeb4027f17c4316a02285baaf446872d2df37b1144ac3ce18d62ab9c786b1f1fb18a53acea1d"
So, why are the hashes different?
I would be very happy if someone could tell me how to adapt the Closure-Code, to get the same hash as the CryptoJS code provides.
Thanks a lot!
PS:
I also tried:
var parameter = "Akuwnm2318kwioasdjlnmn";
var urlDecoded = decodeURIComponent(parameter);
var base64DecodedByteArray = goog.crypt.base64.decodeStringToByteArray(urlDecoded);
var sha512 = new goog.crypt.Sha512();
sha512.update(base64DecodedByteArray);
var hashed = sha512.digest();
hashed = goog.crypt.byteArrayToHex(hashed);
//hashed = "531ba9908e7e764854a2b43e2b7f93a9cb7558d5248f723a37bea0f3609b350d04007fe75a3aa2f425b941e735beafea6a434861e5deaa200f3950159337fd98"
but then, as you see, i get another hash. why??
The first hash value is identical to the third, except it is base64-encoded rather than hex-encoded. You can change to hex encoding and get the same value:
var hashed = CryptoJS.SHA512(base64Decoded).toString(CryptoJS.enc.Hex);
//hashed = "531ba9908e7e764854a2b43e2b7f93a9cb7558d5248f723a37bea0f3609b350d04007fe75a3aa2f425b941e735beafea6a434861e5deaa200f3950159337fd98"
The second approach you show has a different value because you are not hashing the same data; you are instead converting the byteArray to a hex string and then hashing that string representation, not the underlying values.

combined RC4 RSA encrypt/decrypt for long messages Javascript

NOTE: Yes, I understand there is a lot of code in this message, but you do encourage us to show prior research and how we've been trying.
Let me preface this by saying, I am not interested in the security of this function. All I want is to encrypt and decrypt arbitrarily long messages using RSA. Usually to do this, the message is encrypted using a block cipher (such as AES) and encrypting the key with the RSA cipher. However, I am just trying to find the easiest way to encrypt/decrypt long messages, irregardless of security. Hence why I am using RC4 in place of the block cipher.
Now, I can encrypt properly using the following code:
function encryptLong(signedCert, msg) {
var key256Bits = CryptoJS.SHA256("password");
var ciphertext = CryptoJS.RC4.encrypt(msg, key256Bits);
key = new RSAKey();
var m = CryptoJS.SHA256("password").toString(CryptoJS.enc.Hex);
m = new BigInteger(m, 16);
key.setPublic(signedCert.msg.subject.pk.n, signedCert.msg.subject.pk.e);
var ctxt = key.doPublic(m).toString(16);
var cipherstring = ciphertext + ":" + ctxt;
var obj = { "type": "CTXT-LONG", "encrypted": cipherstring };
return JSON.stringify(obj);
}
The message and the key are encrypted properly. I tested them individually using these functions.
function encryptRSA(signedCert, msg) {
//create a new RSA key object
var key = new RSAKey();
//convert ASCII message to hex
var m = asciiToHex(msg);
// create new BigInterger from m
m = new BigInteger(m, 16);
// set the values for the public key
key.setPublic(signedCert.msg.subject.pk.n, signedCert.msg.subject.pk.e);
// compute the RSA public key operation, and convert to a hex value
var ctxt = key.doPublic(m).toString(16);
//enter ctxt into the JSON obj
var obj = { "type": "CTXT-SHORT", "c": ctxt };
return JSON.stringify(obj);
}
And...
function encryptRSA(password, message) {
var key256Bits = CryptoJS.SHA256(password);
var ciphertext = CryptoJS.RC4.encrypt(CryptoJS.enc.Utf8.parse(message), key256Bits);
return ciphertext;
}
Now, here is our decryption code:
function decryptLong(sk, ctxt) {
key = new RSAKey();
encryptedStuff = JSON.stringify(ctxt.encrypted);
log(encryptedStuff);
splitEncryptedstuff = encryptedStuff.split(":");
rsaencryption = splitEncryptedstuff[1];
log(rsaencryption);
rc4encryption = splitEncryptedstuff[0];
log(rc4encryption);
c = new BigInteger(rsaencryption, 16);
key.setPrivate(sk.n, sk.e, sk.d);
var key256Bits = key.doPrivate(c).toString(16);
log(key256Bits);
// RC4 decryption
var message = CryptoJS.RC4.decrypt(rc4encryption, key224Bits);
// var ptxt = CryptoJS.enc.Utf8.stringify(message);
// log(ptxt);
return CryptoJS.enc.Utf8.stringify(message);
}
This code doesn't decrypt properly, but I know parts of it work. For example, where I have
log(key356Bits);
it returns the key exactly. So I know that at least the RSA decryption works. What I don't understand is, I followed the decryption function that I have exactly. Which is as follows.
function decryptRC4(password, ciphertext) {
var key256Bits = CryptoJS.SHA256(password);
var message = CryptoJS.RC4.decrypt(ciphertext, key256Bits);
return CryptoJS.enc.Utf8.stringify(message);
}
Well not exactly, I don't have to take the Hash of the password to get the key, as I already have the key. But, I still don't understand what is not working. When we decrypt our ciphertext using this individual function, the plaintext is correct.
Any assistance in this matter would be greatly appreciated.
Knowing my luck, it's probably just something annoying like it's in the wrong encoding type thing.

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