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javascriptcryptojs

Decrypt in Crypto-JS gives numeric hexadecimal output instead of original plaintext string

I put together a simple test using the example from the Crypto-JS source site at Google code:

In page header:

<script src="http://crypto-js.googlecode.com/svn/tags/3.1.2/build/rollups/aes.js"></script>

In a Javascript function:

var encrypted = CryptoJS.AES.encrypt("Message", "Secret Passphrase");
var decrypted = CryptoJS.AES.decrypt(encrypted, "Secret Passphrase");

alert('encrypted: '+encrypted+'  decrypted: '+decrypted);

but the output is:

encrypted: U2FsdGVkX19hsNqFBS5xcUoVBCu/hPHepEwZchqnUVU=
decrypted: 4d657373616765

image of decrypted output

What am I missing?

Solution 
  • decrypted.toString(CryptoJS.enc.Utf8) // "Message"

    See https://code.google.com/p/crypto-js/#The_Hasher_Output

    The hash you get back isn't a string yet. It's a WordArray object. When you use a WordArray object in a string context, it's automatically converted to a hex string.

    You can convert a WordArray object to other formats by explicitly calling the toString method and passing an encoder.