Review

Uses a non-random key in CBC mode.

• missing/condition/value_or_state

server/generateChecksumPostsAndReplies.java

main(String[])

class generateChecksumPostsAndReplies {
	/**
	 * @param args
	 */
	public static void main(String[] args) throws Exception{

		/*make decoder*/
		DESKeySpec keySpec = new DESKeySpec(CryptoUtil.decode("92LlYoVU1hU="));
		SecretKeyFactory factory = SecretKeyFactory.getInstance("DES");
		SecretKey key = factory.generateSecret(keySpec);
		
		byte[] iv = CryptoUtil.decode(decAndCheck.substring(0, 12));
		Cipher c = Cipher.getInstance("DES/CBC/PKCS5Padding");
		IvParameterSpec ivSpec = new IvParameterSpec(iv);
		c.init(Cipher.DECRYPT_MODE, key, ivSpec);
		
		byte[] content = c.doFinal(CryptoUtil.decode(decAndCheck.substring(12)));
		System.out.println(new String(content, "UTF8"));
		byte[] checksum = Hash.generateChecksum(content);
		System.out.println("\"" + CryptoUtil.encode(checksum) + "\"");
		
	}

}

public class DES {
	public void encrypt(String strDataToEncrypt) {
		try {
			KeyGenerator keyGen = KeyGenerator.getInstance("DES");
			SecretKey secretKey = keyGen.generateKey();
			Cipher desCipher = Cipher.getInstance("DES/CBC/NoPadding");
			desCipher.init(Cipher.ENCRYPT_MODE,secretKey);
			byte[] byteDataToEncrypt = strDataToEncrypt.getBytes();
			byte[] byteCipherText = desCipher.doFinal(byteDataToEncrypt);
		}
		catch (NoSuchAlgorithmException noSuchAlgo) {
		}
		catch (NoSuchPaddingException noSuchPad) {
		}
		catch (InvalidKeyException invalidKey) {
		}
		catch (BadPaddingException badPadding) {
		}
		catch (IllegalBlockSizeException illegalBlockSize) {
		}
	}
}