微信小程序 用户数据解密详细介绍(2)

import org.bouncycastle.jce.provider.BouncyCastleProvider; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.NoSuchPaddingException; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec; import java.security.*; public class AESUtil { public static final AESUtil instance = new AESUtil(); public static boolean initialized = false; /** * AES解密 * @param content 密文 * @return * @throws InvalidAlgorithmParameterException * @throws NoSuchProviderException */ public byte[] decrypt(byte[] content, byte[] keyByte, byte[] ivByte) throws InvalidAlgorithmParameterException { initialize(); try { Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding"); Key sKeySpec = new SecretKeySpec(keyByte, "AES"); cipher.init(Cipher.DECRYPT_MODE, sKeySpec, generateIV(ivByte));// 初始化 byte[] result = cipher.doFinal(content); return result; } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (NoSuchPaddingException e) { e.printStackTrace(); } catch (InvalidKeyException e) { e.printStackTrace(); } catch (IllegalBlockSizeException e) { e.printStackTrace(); } catch (BadPaddingException e) { e.printStackTrace(); } catch (NoSuchProviderException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } public static void initialize(){ if (initialized) return; Security.addProvider(new BouncyCastleProvider()); initialized = true; } //生成iv public static AlgorithmParameters generateIV(byte[] iv) throws Exception{ AlgorithmParameters params = AlgorithmParameters.getInstance("AES"); params.init(new IvParameterSpec(iv)); return params; } }