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POWhy doesn't this simple AES encryption work?
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copied!<p>Why does not this AES encryption work? I've written it in Java to test, but I am not able to decrypt. I get garbage upon decryption. Why? Its so simple - In the main method, print plain text, encrypt, print cipher text, decrypt, print plain text again. Am I doing something wrong? Please help me figure out the problem.</p> <p><pre><code></p> import javax.crypto.Cipher; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec; public class AESTest { public static void main(String [] args) { try { String plainText = "Hello World!!!!!"; String encryptionKey = "E072EDF9534053A0B6C581C58FBF25CC"; System.out.println("Before encryption - " + plainText); String cipherText = encrypt(plainText, encryptionKey); System.out.println("After encryption - " + cipherText); String decrypted = decrypt(cipherText, encryptionKey); System.out.println("After decryption - " + decrypted); } catch (Exception e) { e.printStackTrace(); } } public static String encrypt(String plainText, String passkey) throws Exception { Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE"); SecretKeySpec key = new SecretKeySpec(hexStringToByteArray(passkey), "AES"); cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(new byte[cipher.getBlockSize()])); String cipherText = new String(cipher.doFinal(plainText.getBytes())); return cipherText; } public static String decrypt(String cipherText, String passkey) throws Exception{ Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE"); SecretKeySpec key = new SecretKeySpec(hexStringToByteArray(passkey), "AES"); cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(new byte[cipher.getBlockSize()])); String plainText = new String(cipher.doFinal(cipherText.getBytes())); return plainText; } public static byte[] hexStringToByteArray(String s) { int len = s.length(); byte[] data = new byte[len / 2]; for (int i = 0; i < len; i += 2) { data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4) + Character.digit(s.charAt(i+1), 16)); } return data; } } </code></pre>

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