AES encryption in Java and decryption in JavaScript using CryptoJS

• In the CryptoJS-documentation , it is explained which data types and parameters are CryptoJS.decrypt()expected by -method and which encoders are available:

  • The key must be passed as the to CryptoJS.decrypt()-method WordArray. Since the key data is Base64 encoded, you can WordArrayuse CryptoJS.enc.Base64.parse()the -method to convert it to .
  • Ciphertext can be passed to -method as internal to CryptoJS.decrypt()-object . The Java code stores the encrypted data in a file. Assuming that the string contains those data as hex strings (unfortunately this is not from the posted code, so that has to be assumed here), you can use the -method to convert them to -, and Wrapped in -object.WordArrayCipherParamsencryptedContentWordArrayCryptoJS.enc.Hex.parse()CipherParams
  • CryptoJS.decrypt()The -method returns a string that WordArraycan be converted with -method.CryptoJS.enc.Utf8.stringify()

• If the input file contains the following plain text:

  This is the plain text which needs to be encrypted!
  

  The Java code stores the following sequence of bytes (= encrypted data) in the output file:

  52F415AB673427C42278E8D6F34C16134D7E3FE7986500980ED4063F3CF51162592CE0F5412CCA0BC2DBAE3F2AEC2D585EE8D7
  

  The JavaScript code for decryption is:

  var key = CryptoJS.enc.Base64.parse('uQsaW+WMUrjcsq1HMf+2JQ==');
  
  var encryptedContent = '52F415AB673427C42278E8D6F34C16134D7E3FE7986500980ED4063F3CF51162592CE0F5412CCA0BC2DBAE3F2AEC2D585EE8D7';
  var cipherParams = CryptoJS.lib.CipherParams.create({
      ciphertext: CryptoJS.enc.Hex.parse(encryptedContent)         
  });
  
  var decrypted = CryptoJS.AES.decrypt(cipherParams, key, {
      mode: CryptoJS.mode.CTR,
      iv: key,
      padding: CryptoJS.pad.NoPadding
  });
  
  var decryptedText = CryptoJS.enc.Utf8.stringify(decrypted);
  console.log(decryptedText); 
  

Displays raw plain text in the console. To run code above at least CryptoJS-version 3.1.4 (see version , cdnjs ).