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POAndroid Cipher problems. InvalidKeyException?
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copied!<p>I'm trying to create an application for Android that uses encryption to save user information and I cannot figure out what I'm doing wrong. I'm trying to create an instance of an AES cipher but the application keeps on throwing "InvalidKeyExceptions." Consider the following code:</p> <pre><code>public static final byte[] IV = new byte[] { 0x04, 0x08, 0x15, 0x16, 0x23, 0x42, 0x00, 0x00, 0x00, 0x00,0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f}; protected final IvParameterSpec params = new IvParameterSpec(IV); protected Cipher myCipher; public AESEncryptor(String passwd, InputStream source, String destinationFile) { try { myCipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); Log.d("System.out.println", "Block Size: "+myCipher.getBlockSize()); myCipher.init(Cipher.ENCRYPT_MODE, AESEncryptor.generateSecretKeyFromPassword(passwd),params); } catch (Exception e) { e.printStackTrace(); } } </code></pre> <p>I get this exception:</p> <blockquote> <p>java.security.InvalidKeyException: initialisation vector must be the same length as block size..</p> </blockquote> <p>The myCipher.init(...) line triggers this exception.</p> <p>I understand what it's saying but according to myCipher.getBlockSize() the IV byte array should hold 16 bytes, and it does, but it doesn't work. I have also tried byte arrays of length 0-128, and nothing in that range works either. </p> <p>Oh also, if I take this code, unaltered, and add it to a regular Java application, I get no errors. Compiling for Android seems to be causing this error.</p> <p>Please help. Thanks, Ryan</p>

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