package com.king.weixin.util;
import java.io.UnsupportedEncodingException;
import java.security.AlgorithmParameters;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.SecureRandom;
import java.security.Security;
import java.security.spec.InvalidParameterSpecException;
import java.util.Arrays;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.codehaus.xfire.util.Base64;
import net.sf.json.JSONObject;
public class AesUtil
{
/**
* 解密encryptedData获取用户信息
*/
public JSONObject getUserInfo(String encryptedData,String sessionkey,String iv){
// 被加密的数据
byte[] dataByte = Base64.decode(encryptedData);
// 加密秘钥
byte[] keyByte = Base64.decode(sessionkey);
// 偏移量
byte[] ivByte = Base64.decode(iv);
try {
// 如果密钥不足16位，那么就补足. 这个if 中的内容很重要
int base = 16;
if (keyByte.length % base != 0) {
int groups = keyByte.length / base + (keyByte.length % base != 0 ? 1 : 0);
byte[] temp = new byte[groups * base];
Arrays.fill(temp, (byte) 0);
System.arraycopy(keyByte, 0, temp, 0, keyByte.length);
keyByte = temp;
}
// 初始化
Security.addProvider(new BouncyCastleProvider());
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding","BC");
SecretKeySpec spec = new SecretKeySpec(keyByte, "AES");
AlgorithmParameters parameters = AlgorithmParameters.getInstance("AES");
parameters.init(new IvParameterSpec(ivByte));
cipher.init(Cipher.DECRYPT_MODE, spec, parameters);// 初始化
byte[] resultByte = cipher.doFinal(dataByte);
if (null != resultByte && resultByte.length > 0) {
String result = new String(resultByte, "UTF-8");
return JSONObject.fromObject(result);
}
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
} catch (InvalidParameterSpecException e) {
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (InvalidAlgorithmParameterException e) {
e.printStackTrace();
} catch (NoSuchProviderException e) {
e.printStackTrace();
}
return null;
}
}
