我有 1000 多张图片和视频需要加密。没有什么比这更简单了,我正在考虑使用 AES,但我不知道如何在我的计算机上加密然后解密设备上的项目。
我可能会使用 python 加密计算机上的所有项目。然后以按需方式使用 java(Android 应用程序)解密该项目
任何简单的解释都可以,伪代码也可以。
我遇到的主要问题是如何使用相同的 key 来加密和解密。我一直在生成 key ,但无法将其移植到其他设备进行解密。
谢谢
Python 代码。 Works 加密和解密。
from Crypto.Cipher import AES
import os, random, struct
key = '0123456789abcdef'
mode = AES.MODE_CBC
chunksize = 64*1024
iv = ''.join(chr(random.randint(0,0xFF)) for i in range(16))
encryptor = AES.new(key,mode,iv)
filesize = os.path.getsize('sample.jpg')
with open('sample.jpg','rb') as infile:
with open('sample.enc','wb') as outfile:
outfile.write(struct.pack('<Q',filesize))
outfile.write(iv)
while True:
chunk = infile.read(chunksize)
if len(chunk) == 0:
break
elif len(chunk) % 16 != 0:
chunk += ' ' * (16 - len(chunk) % 16)
outfile.write(encryptor.encrypt(chunk))
## decrypt
with open('sample.enc', 'rb') as infile:
origsize = struct.unpack('<Q', infile.read(struct.calcsize('Q')))[0]
iv = infile.read(16)
decryptor = AES.new(key, AES.MODE_CBC, iv)
with open('sample2.jpg', 'wb') as outfile:
while True:
chunk = infile.read(chunksize)
if len(chunk) == 0:
break
outfile.write(decryptor.decrypt(chunk))
outfile.truncate(origsize)
我将如何在 Java 中完成解密部分?这是我快速草率的 java 代码,它不起作用。我认为是填充弄乱了它。
public void decryptFile(){
String inFile = "sample.enc";
String outFile = "sample.jpg";
String dir = Environment.getExternalStorageDirectory() +"/Android/data/HOT/";
InputStream is ;
byte[] iv = new byte[16];
try {
is = new FileInputStream(dir+inFile);
is.read(iv);
} catch (FileNotFoundException e1) {
// TODO Auto-generated catch block
Log.d("D1","no file found");
} catch (IOException e) {
// TODO Auto-generated catch block
Log.d("D-2","no file found");
e.printStackTrace();
}
byte[] k = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
Key key = new SecretKeySpec(k,"AES");
try {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key,new IvParameterSpec(iv));
OutputStream outs = new FileOutputStream(dir+outFile);
is = new FileInputStream(dir+inFile);
while(true){
byte[] chunk = new byte[64*1024];
is.read(chunk);
if(chunk.length == 0){
break;
}
outs.write(cipher.doFinal(chunk));
}
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
Log.d("D","1");
e.printStackTrace();
} catch (NoSuchPaddingException e) {
// TODO Auto-generated catch block
Log.d("D","2");
e.printStackTrace();
} catch (InvalidKeyException e) {
// TODO Auto-generated catch block
Log.d("D","3");
e.printStackTrace();
} catch (InvalidAlgorithmParameterException e) {
// TODO Auto-generated catch block
Log.d("D","4");
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
Log.d("D","5");
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
Log.d("D","6");
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
// TODO Auto-generated catch block
Log.d("D","7");
e.printStackTrace();
} catch (BadPaddingException e) {
// TODO Auto-generated catch block
Log.d("D","8");
e.printStackTrace();
}
ImageView im = (ImageView)findViewById(R.id.imageView2);
Bitmap mainBitmap = BitmapFactory.decodeFile(dir+outFile);
im.setImageBitmap(mainBitmap);
}
请您参考如下方法:
与 Python 版本不同,在 Java 版本中,您似乎在读取 IV 之前没有读取文件大小。
您还打开了第二个 FileInputStream,然后在读取 Cipher block 之前不要跳过文件大小和 IV。
要检查的另一件事是键在 Java 和 Python 中的解释相同,即 Python 中的字符串产生与 Java 中的字节数组相同的字节序列。
