将密钥转换为字节，如何将其转换回密钥？

我使用以下代码将密钥转换为字节

SecretKey key = KeyGenerator.getInstance("DES").generateKey(); byte[] bkey=key.getEncoded(); 

现在如何从bkey获取密钥？ 我试过了：

 SecretKeySpec secretkey = new SecretKeySpec(bkey,"DES"); SecretKeyFactory sfkey = SecretKeyFactory.getInstance("DES"); SecretKey skey = sfkey.generateSecret(secretkey); 

我收到以下错误：

 Error during Exception java.security.spec.InvalidKeySpecException: Inappropriate key specification 

Answer 1

这应该工作

  SecretKey key = KeyGenerator.getInstance("DES").generateKey(); byte[] data = key.getEncoded(); SecretKey key2 = new SecretKeySpec(data, 0, data.length, "DES"); 

Answer 2

尝试一下这段代码……

 import javax.crypto.Cipher; import javax.crypto.BadPaddingException; import javax.crypto.IllegalBlockSizeException; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; import java.security.Key; import java.security.InvalidKeyException; public class DESede { private static String algorithm = "DESede"; private static Key key = null; private static SecretKey secretKey = null; private static Cipher cipher = null; private static DESede obj = new DESede(); private DESede() { try { key = KeyGenerator.getInstance(algorithm).generateKey(); KeyGenerator.getInstance(algorithm).getProvider(); byte[] keyBytes = key.getEncoded(); String keyFormat = key.getFormat(); String keyAlgorithm = key.getAlgorithm(); String keyString = new String(keyBytes); System.out.println("Key Format::" + keyFormat); System.out.println("Key Algorithm::" + keyAlgorithm); System.out.println("Key String::" + keyString); keyString.getBytes(); secretKey = new SecretKeySpec(keyBytes, 0, keyBytes.length, "DESede"); byte[] secretKeyBytes = key.getEncoded(); String secretKeyFormat = key.getFormat(); String secretKeyAlgorithm = key.getAlgorithm(); String secretKeyString = new String(secretKeyBytes); System.out.println("Secret Key Format::" + secretKeyFormat); System.out.println("Secret Key Algorithm::" + secretKeyAlgorithm); System.out.println("Secret Key String::" + secretKeyString); String keyNewString = "bXŒ*êÂÕê›æOÄ'Îý'ãô|8¶Ë1"; byte[] keyNewBytes = keyString.getBytes(); secretKey = new SecretKeySpec(keyBytes, 0, keyBytes.length, "DESede"); cipher = Cipher.getInstance(algorithm); } catch (Exception e) { } } public static DESede getInstance() { return obj; } public static byte[] encrypt(String input) throws InvalidKeyException, BadPaddingException, IllegalBlockSizeException { System.out.println("Inside encrypt()"); cipher.init(Cipher.ENCRYPT_MODE, secretKey); byte[] inputBytes = input.getBytes(); System.out.println("Exit encrypt()"); return cipher.doFinal(inputBytes); } public static String decrypt(byte[] encryptionBytes) throws InvalidKeyException, BadPaddingException, IllegalBlockSizeException { System.out.println("Inside decrypt()"); cipher.init(Cipher.DECRYPT_MODE, secretKey); byte[] recoveredBytes = cipher.doFinal(encryptionBytes); String recovered = new String(recoveredBytes); System.out.println("Exiting decrypt()"); return recovered; } public static void main(String args[]) throws InvalidKeyException, BadPaddingException, IllegalBlockSizeException { byte[] encryptedValue = DESede.encrypt("plz try encrypt and decrypt me"); System.out.println("encryptedValue::" + encryptedValue); String decryptedValue = DESede.decrypt(encryptedValue); System.out.println("decryptedValue::" + decryptedValue); } }