AES / CBC / PKCS5Padding Java加密錯誤-javax.crypto.BadPaddingException：給定最終塊未正確填充

Question

我正在嘗試使用AES / CBC / PKCS5Padding對字符串進行加密-解密我遇到了以下異常：javax.crypto.BadPaddingException：給定最終塊的填充不正確

我要加密的字符串：ftp.clarapoint.com

這是我的加密代碼：

cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");        
cipher.init(Cipher.ENCRYPT_MODE, aesKey);
byte[] data = cipher.doFinal(stringDec.getBytes());
byte[] iv = cipher.getIV();

我正在傳輸以下解密方法： aesKey，data和iv

解密代碼：

Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
AlgorithmParameters.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, aesKey, new IvParameterSpec(iv));
byte[] decrypted = cipher.doFinal(data);

謝謝！

Answer 1

您未正確傳輸密鑰或密文，因為此代碼會運行：

private static void testCode() {
    try {
        String stringDec = "Hi there";
        SecretKey aesKey = new SecretKeySpec(new byte[16], "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, aesKey);

        // no encoding given, don't use getBytes() without a Charset.forName("UTF-8")
        byte[] data = cipher.doFinal(stringDec.getBytes());
        byte[] iv = cipher.getIV();

        // doesn't do anything
        AlgorithmParameters.getInstance("AES");

        cipher.init(Cipher.DECRYPT_MODE, aesKey, new IvParameterSpec(iv));
        byte[] decrypted = cipher.doFinal(data);
        System.out.println(new String(decrypted));
    } catch (GeneralSecurityException e) {
        throw new IllegalStateException(e);
    }
}