这是我用于加密和解密过程的当前代码,它的工作方式也应该如何,除了加密和解密的时间很长。
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.crypto.Cipher;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
public class EncryptAndDecrypt{
public static void main(String[] args) {
try {
String key = "myencryptedpass123";
FileInputStream fis = new FileInputStream("File_to_encrypt.mp4");
FileOutputStream fos = new FileOutputStream("Encrypted_file.mp4");
encrypt(key, fis, fos);
FileInputStream fis2 = new FileInputStream("Encrypted_file.mp4");
FileOutputStream fos2 = new FileOutputStream("File_to_decrypt.mp4");
decrypt(key, fis2, fos2);
} catch (Throwable e) {
e.printStackTrace();
}
}
public static void encrypt(String key, InputStream is, OutputStream os) throws Throwable {
encryptOrDecrypt(key, Cipher.ENCRYPT_MODE, is, os);
}
public static void decrypt(String key, InputStream is, OutputStream os) throws Throwable {
encryptOrDecrypt(key, Cipher.DECRYPT_MODE, is, os);
}
public static void encryptOrDecrypt(String key, int mode, InputStream is, OutputStream os) throws Throwable {
DESKeySpec dks = new DESKeySpec(key.getBytes());
SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
SecretKey desKey = skf.generateSecret(dks);
Cipher cipher = Cipher.getInstance("DES");
if (mode == Cipher.ENCRYPT_MODE) {
cipher.init(Cipher.ENCRYPT_MODE, desKey);
CipherInputStream cis = new CipherInputStream(is, cipher);
doCopy(cis, os);
} else if (mode == Cipher.DECRYPT_MODE) {
cipher.init(Cipher.DECRYPT_MODE, desKey);
CipherOutputStream cos = new CipherOutputStream(os, cipher);
doCopy(is, cos);
}
}
public static void doCopy(InputStream is, OutputStream os) throws IOException {
byte[] bytes = new byte[64];
int numBytes;
while ((numBytes = is.read(bytes)) != -1) {
os.write(bytes, 0, numBytes);
}
os.flush();
os.close();
is.close();
}
}
现在我希望有更好的解决方案...
肯定使用更大的缓冲区,但加密主要是 CPU 密集型的,所以它不太可能变得更快。此外
- 如果您"不关心安全漏洞",最好完全放弃加密
- 您正在使用 DES,请不要
- 您正在使用人类可读的字符串作为键 - 不要
- 一旦您使用单独的
Cipher
实例进行加密和解密,该代码可能不起作用 - 如果您使用的是默认值,那么您正在设置自己的麻烦。使用类似
Cipher.getInstance("AES/CBC/PKCS5Padding")
- 如果你想让它在安卓上工作,为什么要在桌面上测试?
是的,如果您在应用程序中包含密钥,您的"DRM"就没有多大用处。
肯定使用更大的缓冲区,但加密主要是 CPU 密集型的,所以它不太可能变得更快。此外
如果您"不关心安全漏洞",最好完全放弃加密您正在使用 DES,请不要您正在使用人类可读的字符串作为键 - 不要一旦您使用单独的密码实例进行加密和解密,该代码可能不起作用如果您使用的是默认值,那么您正在设置自己的麻烦。使用类似 Cipher.getInstance("AES/CBC/PKCS5Padding")
public static void encrypt(File inputFile, File outputFile) throws CryptoException {
doCrypto(Cipher.ENCRYPT_MODE, inputFile, outputFile);
}
public static void decrypt(File inputFile, File outputFile) throws CryptoException {
doCrypto(Cipher.DECRYPT_MODE, inputFile, outputFile);
}
private static void doCrypto(int cipherMode, File inputFile, File outputFile) throws CryptoException {
try {
Key secretKey = new SecretKeySpec(key.getBytes(), ALGORITHM);
Cipher cipher = Cipher.getInstance(TRANSFORMATION);
cipher.init(cipherMode, secretKey);
FileInputStream inputStream = new FileInputStream(inputFile);
byte[] inputBytes = new byte[(int) inputFile.length()];
inputStream.read(inputBytes);
byte[] outputBytes = cipher.doFinal(inputBytes);
FileOutputStream outputStream = new FileOutputStream(outputFile);
outputStream.write(outputBytes);
inputStream.close();
outputStream.close();
} catch (IOException | NoSuchAlgorithmException | InvalidKeyException | NoSuchPaddingException | BadPaddingException | IllegalBlockSizeException e) {
e.printStackTrace();
e.getMessage();
throw new CryptoException("Error encrypting/decrypting file", e);
}
}