java解析微信小程式使用者資訊demo
1、引入maven依賴
<dependency> <groupId>org.bouncycastle</groupId> <artifactId>bcprov-jdk16</artifactId> <version>1.46</version> </dependency>
<dependency> <groupId>commons-codec</groupId> <artifactId>commons-codec</artifactId> <version>1.10</version> </dependency>
<dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.29</version> </dependency>
2、AES解密
package com.bijian.test;
import java.security.AlgorithmParameters; import java.security.InvalidAlgorithmParameterException; import java.security.InvalidKeyException; import java.security.Key; import java.security.NoSuchAlgorithmException; import java.security.NoSuchProviderException; import java.security.Security; 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 org.bouncycastle.jce.provider.BouncyCastleProvider; /** * AES加密 */ public class AES { 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) { e.printStackTrace(); } catch (Exception e) { 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; } }
3、實現WxPKCS7Encoder類
package com.bijian.test;
import java.nio.charset.Charset; import java.util.Arrays;
/** * 微信小程式加解密 */ public class WxPKCS7Encoder { private static final Charset CHARSET = Charset.forName("utf-8"); private static final int BLOCK_SIZE = 32; /** * 獲得對明文進行補位填充的位元組. * * @param count * 需要進行填充補位操作的明文位元組個數 * @return 補齊用的位元組陣列 */ public static byte[] encode(int count) { // 計算需要填充的位數 int amountToPad = BLOCK_SIZE - (count % BLOCK_SIZE); if (amountToPad == 0) { amountToPad = BLOCK_SIZE; } // 獲得補位所用的字元 char padChr = chr(amountToPad); String tmp = new String(); for (int index = 0; index < amountToPad; index++) { tmp += padChr; } return tmp.getBytes(CHARSET); } /** * 刪除解密後明文的補位字元 * * @param decrypted * 解密後的明文 * @return 刪除補位字元後的明文 */ public static byte[] decode(byte[] decrypted) { int pad = decrypted[decrypted.length - 1]; if (pad < 1 || pad > 32) { pad = 0; } return Arrays.copyOfRange(decrypted, 0, decrypted.length - pad); } /** * 將數字轉化成ASCII碼對應的字元，用於對明文進行補碼 * * @param a * 需要轉化的數字 * @return 轉化得到的字元 */ public static char chr(int a) { byte target = (byte) (a & 0xFF); return (char) target; } }
4、可用的api
package com.bijian.test;
import org.apache.commons.codec.binary.Base64;
import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.JSONObject;
/** * 封裝對外訪問方法 */ public class WXCore {
private static final String WATERMARK = "watermark"; private static final String APPID = "appid";
/** * 解密資料 * * @return * @throws Exception */ public static String decrypt(String appId, String encryptedData, String sessionKey, String iv) { String result = ""; try { AES aes = new AES(); byte[] resultByte = aes.decrypt(Base64.decodeBase64(encryptedData), Base64.decodeBase64(sessionKey), Base64.decodeBase64(iv)); if (null != resultByte && resultByte.length > 0) { result = new String(WxPKCS7Encoder.decode(resultByte)); JSONObject jsonObject = JSON.parseObject(result); String decryptAppid = jsonObject.getJSONObject(WATERMARK) .getString(APPID); if (!appId.equals(decryptAppid)) { result = ""; } } } catch (Exception e) { result = ""; e.printStackTrace(); } return result; }
public static void main(String[] args) throws Exception {
String appId = "wx4f4bc4dec97d474b"; String encryptedData = "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"; String sessionKey = "tiihtNczf5v6AKRyjwEUhQ=="; String iv = "r7BXXKkLb8qrSNn05n0qiA=="; System.out.println(decrypt(appId, encryptedData, sessionKey, iv)); } }