使用javax.security.cert.X509Certificate進行解析

URL url = Demo.class.getClassLoader().getResource('C000024.crt'); //證書路徑System.out.println('公鑰所在路徑:'+url.getFile());X509Certificate cert = X509Certificate.getInstance(new FileInputStream(url.getFile()));PublicKey publicKey = cert.getPublicKey();BASE64Encoder base64Encoder=new BASE64Encoder();String publicKeyString = base64Encoder.encode(publicKey.getEncoded());System.out.println('-----------------公鑰--------------------');System.out.println(publicKeyString);System.out.println('-----------------公鑰--------------------');方式2：

使用java.security.cert.X509Certificate進行解析

URL url = Demo.class.getClassLoader().getResource('C000024.crt'); //證書路徑System.out.println('公鑰所在路徑:'+url.getFile());CertificateFactory cf = CertificateFactory.getInstance('X.509');X509Certificate cert = (X509Certificate)cf.generateCertificate(new FileInputStream(url.getFile()));PublicKey publicKey = cert.getPublicKey(); BASE64Encoder base64Encoder=new BASE64Encoder();String publicKeyString = base64Encoder.encode(publicKey.getEncoded());System.out.println('-----------------公鑰--------------------');System.out.println(publicKeyString);System.out.println('-----------------公鑰--------------------');

說明：

因為只做示例，沒有進行異常處理和流的釋放，方式1的代碼可能少點，方式2需要強轉，美觀上可能方式1更好看點，但方式1的實質還是調用的方式2，方式2內部有實現緩存策略。更多可以參考下api文檔，文檔上有提供示例。

補充：JAVA生成RSA公鑰和私鑰及RSA對數據的加簽和驗簽

最近來到了新的公司，公司做的是保險支付相關業務，對接渠道的時候經常會用到數據的加簽和驗簽，初次涉及RSA加簽驗簽，通過網站生成了RSA公鑰和私鑰，用私鑰將我要傳送的數據進行了加簽，并將我的公鑰提供給了渠道方進行驗簽，結果在聯調的時候，驗簽總是錯誤，渠道方用自己的私鑰對數據加簽后再用自己的公鑰對數據進行驗簽卻能通過，于是我也用自己的私鑰對數據進行加簽后再用自己的公鑰對數據進行驗簽，結果讓我驚訝，居然沒有通過！

到了這里，產生錯誤的原因基本上已經一目了然了，我通過網站生成的公私鑰是無法配對的，這當中可能涉及到了網站生成公私鑰的時候已經對公私鑰進行了處理，比如說PKCS8的處理，所以決定自己用Java來生成RSA公鑰和私鑰進行驗證測試，文檔寫出來了，測試結果自然已經知道了，是通過的。

啟動類：ZhongbaohuiApplication.java

package com.test.zhongbaohui; import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplicationpublic class ZhongbaohuiApplication { public static void main(String[] args) { SpringApplication.run(ZhongbaohuiApplication.class, args); }}

請求Controller：RequestController.java

package com.test.zhongbaohui.controller; import com.alibaba.fastjson.JSONObject;import com.test.zhongbaohui.utils.RSASignUtils;import lombok.extern.slf4j.Slf4j;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.PostMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController; import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.util.HashMap;import java.util.Map; /** * @program: zhongbaohui * @package: com.test.zhongbaohui.controller * @description: * @auther: chengjunyu * @createDate: 2019/12/6 22:05 */@RestController@RequestMapping(value='/test')@Slf4jpublic class RequestController { @Autowired private ResponseController responseController; @PostMapping('/getJsonObject') private String getJsonObject(HttpServletRequest request, HttpServletResponse response) { JSONObject jsonObject = new JSONObject(); jsonObject.put('signType', 'RSA'); jsonObject.put('enterpriseId', '201975538583911110'); jsonObject.put('nonce', 'b0eed33073664f5fa983c5b774dbd4b6'); jsonObject.put('timestamp', '2019-12-07 01:19:25'); Map<String, Object> map = new HashMap<>(); map.put('bankCode', '其他'); map.put('batchNo', '201975538583911110b1084fa29f6c'); map.put('bankCardNumber', '6217856100077026406'); map.put('paymentNote', '傭金發放'); map.put('idCardNumber', '320123199103104650'); map.put('mobile', '15365176555'); map.put('bankName', '中國銀行'); map.put('outEnterpriseOrderNo', 'T20191207011545663692017'); map.put('realPayment', '1.00'); map.put('serviceId', '201968613430727001'); map.put('userName', '程俊予'); jsonObject.put('data', map); //私鑰內容 String privateKey = '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'; String sign = RSASignUtils.sign(jsonObject, privateKey); log.info('驗簽sign為：{}', sign); jsonObject.put('sign', sign); String message = responseController.returnMsg(jsonObject.toJSONString()); return message; }}

響應Controller：ResponseController.java

package com.test.zhongbaohui.controller; import com.alibaba.fastjson.JSON;import com.alibaba.fastjson.JSONObject;import com.test.zhongbaohui.utils.RSASignUtils;import lombok.extern.slf4j.Slf4j;import org.springframework.web.bind.annotation.PostMapping;import org.springframework.web.bind.annotation.RestController; /** * @program: zhongbaohui * @package: com.test.zhongbaohui.controller * @description: * @auther: chengjunyu * @createDate: 2019/12/7 20:46 */@RestController@Slf4jpublic class ResponseController { @PostMapping('/returnMsg') public String returnMsg(String message) { JSONObject jsonObject = JSONObject.parseObject(message); log.info('接受請求內容為：{}', jsonObject.toJSONString()); String sign = jsonObject.getString('sign'); jsonObject.remove('sign'); String publicKey = 'MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQD5gn/eAnLyf6xZziA+emDarsHp64J1tVHfhgXEhaIzzmNNPk2Kv6h1Wqaxj3ripQHAXm5Mo+Phtx+Le3tQ0zm5ULWZP8ovtlXGw54R0Jd1FXZC5FTEV1wgTwSbY0qN0TDCRQujgoin84bo4YYqOzCVlqzGC7QIDAQAB'; boolean flag = RSASignUtils.verify(jsonObject, publicKey, sign); JSONObject object = new JSONObject(); if(flag) { object.put('code', '200'); object.put('status', 'success'); object.put('message:', '驗簽成功'); }else { object.put('code', '400'); object.put('status', 'failure'); object.put('message:', '驗簽失敗'); } return object.toJSONString(); }}

RSA工具類：RSASignUtils.java

package com.test.zhongbaohui.utils; import com.alibaba.fastjson.JSONObject;import lombok.extern.slf4j.Slf4j;import org.apache.tomcat.util.codec.binary.Base64;import org.springframework.stereotype.Component;import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder; import java.io.IOException;import java.io.UnsupportedEncodingException;import java.security.*;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.InvalidKeySpecException;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.util.HashMap;import java.util.Map; /** * @program: zhongbaohui * @package: com.test.zhongbaohui.controller * @description: * @auther: chengjunyu * @createDate: 2019/12/6 23:03 */@Slf4j@Componentpublic class RSASignUtils { public static final String KEY_ALGORITHM = 'RSA'; private static final String PUBLIC_KEY = 'RSAPublicKey'; private static final String PRIVATE_KEY = 'RSAPrivateKey'; public static final String SIGNATURE_ALGORITHM='MD5withRSA'; public static final Integer RSA_KEY_SIZE = 1024; /* * @function: 使用字符串格式的私鑰為JSONObject格式的內容加簽 * @param: [jsonObject, privateKey] * @return: java.lang.String * @auther: chengjunyu * @date: 2019/12/7 21:06 */ public static String sign(JSONObject jsonObject, String privateKey) { String signMsg = ''; String data = jsonObject.toString(); log.info('加簽對象內容為：{}', data); try { byte[] keyBytes = decryptBASE64(privateKey); PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance('RSA'); PrivateKey key = keyFactory.generatePrivate(keySpec); Signature signature = Signature.getInstance('MD5withRSA'); signature.initSign(key); signature.update(data.getBytes('ISO-8859-1')); signMsg = Base64.encodeBase64String(signature.sign()); } catch (Exception var8) { var8.printStackTrace(); } return signMsg; } /* * @function: 使用字符串格式的公鑰為JSONObject格式的內容驗簽 * @param: [jsonObject, publicKey, sign] * @return: boolean * @auther: chengjunyu * @date: 2019/12/8 14:56 */ public static boolean verify(JSONObject jsonObject, String publicKey, String sign) { String s = jsonObject.toJSONString(); log.info('s:{}',s); boolean rs = false; try { byte[] keyBytes = decryptBASE64(publicKey); X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance('RSA'); PublicKey key = keyFactory.generatePublic(keySpec); Signature signature = Signature.getInstance('MD5withRSA'); signature.initVerify(key); signature.update(s.getBytes('ISO-8859-1')); return signature.verify(Base64.decodeBase64(sign.getBytes())); } catch (Exception var9) { var9.printStackTrace(); return rs; } } /* * @function: 獲取PublicKey格式的公鑰，本例中未使用 * @param: [key] * @return: java.security.PublicKey * @auther: chengjunyu * @date: 2019/12/8 16:10 */ public static PublicKey getPublicKey(String key) { PublicKey publicKey = null; try { byte[] keyBytes = (new BASE64Decoder()).decodeBuffer(key); X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes); // RSA對稱加密算法 KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM); // 取公鑰匙對象 publicKey = keyFactory.generatePublic(keySpec); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (InvalidKeySpecException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return publicKey; } /* * @function: 獲取PublicKey格式的私鑰，本例中未使用 * @param: [key] * @return: java.security.PrivateKey * @auther: chengjunyu * @date: 2019/12/8 16:10 */ public static PrivateKey getPrivateKey(String key) { PrivateKey privateKey = null; try { byte[] keyBytes = (new BASE64Decoder()).decodeBuffer(key); PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM); privateKey = keyFactory.generatePrivate(keySpec); } catch (IOException e) { e.printStackTrace(); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (InvalidKeySpecException e) { e.printStackTrace(); } return privateKey; } /* * @function: 初始化公鑰和私鑰 * @param: [] * @return: java.util.Map<java.lang.String,java.lang.Object> * @auther: chengjunyu * @date: 2019/12/8 14:34 */ public static Map<String, Object> initKey() { KeyPairGenerator keyPairGen = null; try { keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } keyPairGen.initialize(RSA_KEY_SIZE); KeyPair keyPair = keyPairGen.generateKeyPair(); RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic(); RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate(); Map<String, Object> keyMap = new HashMap<String, Object>(2); keyMap.put(PUBLIC_KEY, publicKey); keyMap.put(PRIVATE_KEY, privateKey); return keyMap; } //獲得公鑰字符串 public static String getPublicKeyStr(Map<String, Object> keyMap) { //獲得map中的公鑰對象 轉為key對象 Key key = (Key) keyMap.get(PUBLIC_KEY); //編碼返回字符串 return encryptBASE64(key.getEncoded()); } //獲得私鑰字符串 public static String getPrivateKeyStr(Map<String, Object> keyMap) { //獲得map中的私鑰對象 轉為key對象 Key key = (Key) keyMap.get(PRIVATE_KEY); //編碼返回字符串 return encryptBASE64(key.getEncoded()); } //編碼返回字符串 public static String encryptBASE64(byte[] key) { return (new BASE64Encoder()).encodeBuffer(key); } //解碼返回byte public static byte[] decryptBASE64(String key) { byte[] bytes = null; try { return (new BASE64Decoder()).decodeBuffer(key); } catch (IOException e) { return bytes; } } public static void main(String[] args) { Map<String, Object> keyMap = initKey(); String publicKey = getPublicKeyStr(keyMap); log.info('JAVA生成RSA公鑰：{}', publicKey); String privateKey = getPrivateKeyStr(keyMap); log.info('JAVA生成RSA私鑰：{}', privateKey); }}

注意：

本文中請求和響應類中的私鑰和公鑰均是不完整的，在請求和響應類中的私鑰和公鑰由RSASignUtils工具類生成后，再替代入請求和響應類中，請求類中使用私鑰加簽，響應類中使用公鑰驗簽。

以上為個人經驗，希望能給大家一個參考，也希望大家多多支持好吧啦網。如有錯誤或未考慮完全的地方，望不吝賜教。