Question

对于作业，我们必须解密5个加密的图片文件。这项任务给了我们关键：{“2b 7e 15 16 28 ae d2 a6 ab f7 15 88 09 cf 4f 3c”}：带有填充文件的参数和 1.文件大小以8个字节表示，其中第一个字节是最重要的字节。 2.填充的大小是使[file_size + padding_size + 8]为16的倍数所需的字节数。 3.为加密传递的字节是：original_file，padding，file_size。

以下是我的代码：

enter code here public class AESEncryption {

public static String algo = "AES";
public static String transformation = "AES/ECB/NoPadding";
public static String key = "2b7e151628aed2a6abf7158809cf4f3c";
public static String path = "AESencrypt_1.jpg";

public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeyException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException, IOException {
    //encrypt();
    decrypt();
    bytes();
}

    private static void encrypt() throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IOException{
   Cipher aesCipher = Cipher.getInstance(transformation);
   byte[] b = key.getBytes();
   SecretKeySpec key = new SecretKeySpec(b,"AES");
           aesCipher.init(Cipher.ENCRYPT_MODE, key);

    FileInputStream is = new FileInputStream(path);
    CipherOutputStream os = new CipherOutputStream(new FileOutputStream("ecrypted.jpg"), aesCipher);

    copy(is, os);
    os.close();

}
`

    private static void decrypt()throws NoSuchAlgorithmException,           NoSuchPaddingException, InvalidKeyException, IOException{

    byte[] b = key.getBytes();


             //System.out.println(Arrays.toString(data));
    //CipherInputStream is = new CipherInputStream(new FileInputStream("AESencrypt_1.jpg"), aesCipher);
    //CipherOutputStream os = new CipherOutputStream("decPic.jpg");
    FileInputStream file = new FileInputStream(path);
    FileOutputStream out = new FileOutputStream("Decrypted.jpg");
    Cipher aesCipher = Cipher.getInstance(transformation);

       SecretKeySpec key1 = new SecretKeySpec(b,"AES");
               aesCipher.init(Cipher.DECRYPT_MODE, key1);
    CipherOutputStream outSt = new CipherOutputStream(out,aesCipher);
    byte[] buf = new byte[1024];
    int read;
    while((read=file.read(buf))!=-1){
        outSt.write(buf, 0, read);

    }

    file.close();
    out.flush();
    outSt.flush();

}

private static void copy(InputStream cin, OutputStream fos) throws IOException {
    // TODO Auto-generated method stub
    int i;
    byte[] b = new byte[1024];
    while((i=cin.read(b))!=-1) {
        fos.write(b, 0, i);
    }
  }
}

我的代码接受输入流并保存新的输出文件，但图像仍然不可读。我不确定我是不是以正确的方式传递密钥，或者我是否需要移除填充以便查看图像。如果我这样做，你能指出我正确的方向吗？谢谢。

使用Java AES / ECB解密图像文件

0 个答案: