BadPaddingException：无效的密文
我想要一些帮助，因为这是我第一次编码加密代码。
加密代码似乎正常工作，但解密会引发错误。
我得到的错误是：
de.flexiprovider.api.exceptions.BadPaddingException：无效的密文
在解密函数中朝向代码的末尾，标记为注释
//错误在这里！ …………………………
我已经包含了所有的import产品，请原谅这个，因为它可能与这个问题有关。
非常感谢任何有关我所做错事的帮助。
码：
import java.io.UnsupportedEncodingException; import java.security.KeyFactory; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.PrivateKey; import java.security.PublicKey; import java.security.SecureRandom; import java.security.Security; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import android.app.Activity; import android.os.Bundle; import android.util.Base64; import android.util.Log; import de.flexiprovider.common.ies.IESParameterSpec; import de.flexiprovider.core.FlexiCoreProvider; import de.flexiprovider.ec.FlexiECProvider; import de.flexiprovider.ec.parameters.CurveParams; import de.flexiprovider.ec.parameters.CurveRegistry.BrainpoolP384r1; import de.flexiprovider.pki.PKCS8EncodedKeySpec; import de.flexiprovider.pki.X509EncodedKeySpec; public class MainActivity extends Activity { private static PublicKey PublicKey; private static PrivateKey PrivateKey; private static String PubKey; private static String PrvKey; private static String message = "Hello World"; private static String encryptedMessage; private static String decryptedMessage; private final static String TAG = "ERROR: "; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); try { Security.addProvider(new FlexiCoreProvider()); Security.addProvider(new FlexiECProvider()); // instantiate the elliptic curve key pair generator KeyPairGenerator kpg = KeyPairGenerator.getInstance("ECIES", "FlexiEC"); // choose the curve CurveParams ecParams = new BrainpoolP384r1(); // Initialize the key pair generator kpg.initialize(ecParams, new SecureRandom()); KeyPair keyPair = kpg.generateKeyPair(); // generate the public key PublicKey = keyPair.getPublic(); // generate private key PrivateKey = keyPair.getPrivate(); } catch (Exception e) { Log.e(TAG, e.toString()); } // I'm converting keys to strings here as the public keys will be stored on a server // database and the private keys will be stored in the application preferences file // this private key storage is maybe not optimum, but at this point I just want to // simulate a messaging encryption/decryption process for testing purposes // convert public key to a string PubKey = Base64.encodeToString(PublicKey.getEncoded(), Base64.DEFAULT); Log.d("PubKey: ", PubKey); // convert private key to a string PrvKey = Base64.encodeToString(PrivateKey.getEncoded(), Base64.DEFAULT); Log.d("PrvKey: ", PrvKey); // encrypt the message with the public key encryptedMessage = encryptMessage(PubKey, message); // report if the public key has not been regenerated correctly if (encryptedMessage == null) { Log.d("PUBLIC_KEY_REGENERATE_ERROR: ", encryptedMessage); } // decrypt the message with the private key decryptedMessage = decryptMessage(PrvKey, encryptedMessage); // report if the private key has not been regenerated correctly if (encryptedMessage == null) { Log.d("PRIVATE_KEY_REGENERATE_ERROR: ", decryptedMessage); } } // encrypt function public static String encryptMessage(String publicKey, String message) { KeyFactory keyFactory = null; PublicKey pubkey = null; Cipher cipher = null; byte[] PLAINTEXT_MESSAGE = message.getBytes(); Log.d("PLAINTEXT_MESSAGE: ", message); Security.addProvider(new FlexiCoreProvider()); Security.addProvider(new FlexiECProvider()); // Base64 decode the publicKey string into a byte array byte[] decodedPublicKey = Base64.decode(publicKey, Base64.DEFAULT); try { // instantiate a X509EncodedKeySpec X509EncodedKeySpec X509spec = new X509EncodedKeySpec(decodedPublicKey); keyFactory = KeyFactory.getInstance("ECIES", "FlexiEC"); // re-generate the public key pubkey = keyFactory.generatePublic(X509spec); // sanity check, return null on inequality if (!pubkey.equals(PublicKey)) { return null; } cipher = Cipher.getInstance("ECIES", "FlexiEC"); IESParameterSpec IESspec = new IESParameterSpec("AES256_CBC", "HmacSHA512", null, null); cipher.init(Cipher.ENCRYPT_MODE, pubkey, IESspec); } catch (Exception e) { Log.e(TAG, e.toString()); } // encrypt the message byte[] encryptedData = null; try { encryptedData = cipher.doFinal(PLAINTEXT_MESSAGE); } catch (IllegalBlockSizeException e) { Log.e(TAG, e.toString()); } catch (BadPaddingException e) { Log.e(TAG, e.toString()); } String encryptedMessage = null; try { encryptedMessage = new String(encryptedData, "UTF-8"); } catch (UnsupportedEncodingException e) { Log.e(TAG, e.toString()); } Log.d("encryptedMessage: ", encryptedMessage); return encryptedMessage; } // decrypt function public static String decryptMessage(String privateKey, String message) { KeyFactory keyFactory = null; PrivateKey prvkey = null; Cipher cipher = null; byte[] ENCRYPTED_MESSAGE = message.getBytes(); Log.d("ENCRYPTED_MESSAGE: ", message); Security.addProvider(new FlexiCoreProvider()); Security.addProvider(new FlexiECProvider()); try { // Base64 decode the privateKey string into a byte array byte[] decodedPrivateKey = Base64.decode(privateKey, Base64.DEFAULT); // instantiate a PKCS8EncodedKeySpec PKCS8EncodedKeySpec PKCS8spec = new PKCS8EncodedKeySpec(decodedPrivateKey); keyFactory = KeyFactory.getInstance("ECIES", "FlexiEC"); // re-generate the private key prvkey = keyFactory.generatePrivate(PKCS8spec); // sanity check, return null on inequality if (!prvkey.equals(PrivateKey)) { return null; } cipher = Cipher.getInstance("ECIES", "FlexiEC"); IESParameterSpec IESspec = new IESParameterSpec("AES256_CBC", "HmacSHA512", null, null); cipher.init(Cipher.DECRYPT_MODE, prvkey, IESspec); } catch (Exception e) { Log.e(TAG, e.toString()); } // decrypt the message byte[] decryptedData = null; try { decryptedData = cipher.doFinal(ENCRYPTED_MESSAGE); // ERROR THROWN HERE! .............................. // de.flexiprovider.api.exceptions.BadPaddingException: invalid ciphertext } catch (IllegalBlockSizeException e) { Log.e(TAG, e.toString()); } catch (BadPaddingException e) { Log.e(TAG, e.toString()); } String decryptedMessage = null; try { decryptedMessage = new String(decryptedData, "UTF-8"); } catch (UnsupportedEncodingException e) { Log.e(TAG, e.toString()); } Log.d("decryptedMessage: ", decryptedMessage); return decryptedMessage; } }
您不能只使用密文作为String构造函数的输入，就像您在此行中所做的那样：
encryptedMessage = new String(encryptedData, "UTF-8");
如果要使用字符串而不是字节来传递密文， 则必须像使用密钥一样使用Base 64等编码。
加密将导致数据看起来像随机字节。 并非所有字节都具有等效字符。 转换的结果取决于字符编码。 UTF-8可能使用许多字节，并且许多组合不会产生正确的字符。 Java默默地转换它们，检查Charset和相关类以获取更多信息。