Spring Cloud Gateway+Spring Security OAuth2+JWT（一）

爱被打了一巴掌 2024-04-19 10:54 167阅读 0赞

### Spring Cloud Gateway+Spring Security OAuth2+JWT（一） ###

*  前言
 *  授权服务 OAuth2+JWT
 *   *  pom
     *  授权服务器配置
     *  自定义用户
     *  jwt

# 前言 #

捣鼓了一段时间的Spring cloud,想把公司的的基于用户和权限体系的基础框架也融入到Spring cloud中。查阅了一些相关资料，打算采用Spring Cloud Gateway+Spring Security OAuth2+JWT的方式。基础版本的已经搭好了，也总结一下这几天的成果。

# 授权服务 OAuth2+JWT #

首先说明一下Spring Security OAuth2的交互数据可以有3种方式。

1.  第一钟是基于配置的即内存
2.  第二钟是基于内置数据结构的数据库（Spring Security OAuth2 自己定义了很多表结构和封装好的DAO 我们只要按照它给的表结构创建表就可以用了）
3.  第三种就是我们自己定义的表

我有用了2和3，很多资料都是第一种,自己也研究了半天。不多说直接上代码

## pom ##

如果采用redis存储token的话 要注意一下

<dependency>
    			<groupId>org.springframework.cloud</groupId>
    			<artifactId>spring-cloud-starter-security</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>io.jsonwebtoken</groupId>
    			<artifactId>jjwt</artifactId>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.security.oauth</groupId>
    			<artifactId>spring-security-oauth2</artifactId>
    			
    			<version>2.3.3.RELEASE</version>
    		</dependency>

## 授权服务器配置 ##

这里主要是配置了用户的相关信息，由于我有自己的用户表所以我就采用了实现UserService接口的一个实现类。

package com.ljl.auth.config;
    
    import com.ljl.auth.service.impl.UserServiceImpl;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.http.HttpMethod;
    import org.springframework.security.authentication.AuthenticationManager;
    import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
    import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
    import org.springframework.security.config.annotation.web.builders.HttpSecurity;
    import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
    import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
    import org.springframework.security.core.userdetails.UserDetailsService;
    import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
    import org.springframework.security.crypto.password.PasswordEncoder;
    
    import javax.sql.DataSource;
    
    /** * Created by Administrator on 2019/9/3 0003. * 安全配置 */
    @Configuration
    @EnableWebSecurity
    @EnableGlobalMethodSecurity(prePostEnabled = true)
    public class SecurityConfig extends WebSecurityConfigurerAdapter { 
    
        @Autowired
        private UserServiceImpl userService;
    
        @Autowired
        private DataSource dataSource;
    
        /** * 注入用户信息服务 * @return 用户信息服务对象 */
        @Bean
        public UserDetailsService userDetailsService() { 
            return userService;
        }
    
        /** * 全局用户信息 * @param auth 认证管理 * @throws Exception 用户认证异常信息 */
        @Autowired
        public void globalUserDetails(AuthenticationManagerBuilder auth) throws Exception { 
            //auth.jdbcAuthentication().dataSource(dataSource).passwordEncoder(passwordEncoder());
            auth.userDetailsService(userDetailsService()).passwordEncoder(passwordEncoder());
        }
    
        /** * 认证管理 * @return 认证管理对象 * @throws Exception 认证异常信息 */
        @Override
        @Bean
        public AuthenticationManager authenticationManagerBean() throws Exception { 
            return super.authenticationManagerBean();
        }
    
        /** * http安全配置 * @param http http安全对象 * @throws Exception http安全异常信息 */
        @Override
        protected void configure(HttpSecurity http) throws Exception { 
            http.authorizeRequests().antMatchers(HttpMethod.OPTIONS).permitAll().anyRequest().authenticated().and()
                    .httpBasic().and().csrf().disable();
        }
    
        @Bean
        public PasswordEncoder passwordEncoder() { 
            return new BCryptPasswordEncoder();
        }
    
    }

授权服务器配置。这边主要是token和配置客户端详情信息。  
由于我用了jwt所以就不需要将token存储下来了，所以只用了OAUTH\_CLIENT\_DETAILS这个表。  
OAuth2集成了很多表，可以去查询相关资料。

jwt我采用的是RSA加密的方法，工具类我也贴出来了。

package com.ljl.auth.config;
    
    import com.ljl.common.util.RSAUtil;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.data.redis.connection.RedisConnectionFactory;
    import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
    import org.springframework.security.authentication.AuthenticationManager;
    import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
    import org.springframework.security.crypto.password.PasswordEncoder;
    import org.springframework.security.oauth2.config.annotation.configurers.ClientDetailsServiceConfigurer;
    import org.springframework.security.oauth2.config.annotation.web.configuration.AuthorizationServerConfigurerAdapter;
    import org.springframework.security.oauth2.config.annotation.web.configuration.EnableAuthorizationServer;
    import org.springframework.security.oauth2.config.annotation.web.configurers.AuthorizationServerEndpointsConfigurer;
    import org.springframework.security.oauth2.config.annotation.web.configurers.AuthorizationServerSecurityConfigurer;
    import org.springframework.security.oauth2.provider.token.TokenStore;
    import org.springframework.security.oauth2.provider.token.store.JwtAccessTokenConverter;
    import org.springframework.security.oauth2.provider.token.store.JwtTokenStore;
    import org.springframework.security.oauth2.provider.token.store.redis.RedisTokenStore;
    
    import javax.sql.DataSource;
    
    /** * Created by Administrator on 2019/9/3 0003. * 授权服务器配置 */
    @Configuration
    @EnableAuthorizationServer
    public class AuthorizationServerConfig extends AuthorizationServerConfigurerAdapter { 
    
        // 认证管理器
        @Autowired
        private AuthenticationManager authenticationManager;
        // redis连接工厂
        /*@Autowired private JedisConnectionFactory JedisConnectionFactory;*/
        @Autowired
        private PasswordEncoder passwordEncoder;
        @Autowired
        private DataSource dataSource;
        /** * 令牌存储 * @return redis令牌存储对象 */
        /*@Bean public TokenStore tokenStore() { return new RedisTokenStore(JedisConnectionFactory); } @Override public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception { endpoints.authenticationManager(this.authenticationManager); endpoints.tokenStore(tokenStore()); }*/
    
        @Bean
        protected JwtAccessTokenConverter jwtAccessTokenConverter() { 
            JwtAccessTokenConverter converter = new MyJwtAccessTokenConverter();
            converter.setKeyPair(RSAUtil.GetKeyPair());
            return converter;
        }
    
        @Bean
        public TokenStore jwtTokenStore() { 
            return new JwtTokenStore(jwtAccessTokenConverter());
        }
    
        @Override
        public void configure(AuthorizationServerEndpointsConfigurer endpoints) throws Exception { 
            endpoints.tokenStore(jwtTokenStore()).accessTokenConverter(jwtAccessTokenConverter()).authenticationManager(this.authenticationManager);
        }
    
        /** * OAuth 授权端点开放 */
        @Override
        public void configure(AuthorizationServerSecurityConfigurer security) throws Exception { 
            security
                    // 开启/oauth/token_key验证端口无权限访问
                    .tokenKeyAccess("permitAll()")
                    // 开启/oauth/check_token验证端口认证权限访问
                    .checkTokenAccess("isAuthenticated()")
                    //主要是让/oauth/token支持client_id以及client_secret作登录认证
                    .allowFormAuthenticationForClients();
        }
        /** * OAuth 配置客户端详情信息 */
        @Override
        public void configure(ClientDetailsServiceConfigurer clients) throws Exception { 
            clients.jdbc(dataSource).passwordEncoder(passwordEncoder);
        }
    
    
    }

我用的是oracle

-- Create table
    create table OAUTH_CLIENT_DETAILS
    (
      client_id               VARCHAR2(255) not null,
      resource_ids            VARCHAR2(255),
      client_secret           VARCHAR2(255),
      scope                   VARCHAR2(255),
      authorized_grant_types  VARCHAR2(255),
      web_server_redirect_uri VARCHAR2(255),
      authorities             VARCHAR2(255),
      access_token_validity   NUMBER(11),
      refresh_token_validity  NUMBER(11),
      additional_information  VARCHAR2(255),
      autoapprove             VARCHAR2(255)
    )
    tablespace BASE
      pctfree 10
      initrans 1
      maxtrans 255
      storage
      (
        initial 64K
        next 1M
        minextents 1
        maxextents unlimited
      );

## 自定义用户 ##

自定义用户表的话主要是需要实现UserService这个接口中的loadUserByUsername方法并返回一个uesr对象。  
这边的查询用户是我另一个基础服务的一个接口，就是通过用户名查询数据。

package com.ljl.auth.service.impl;
    
    
    
    import com.alibaba.fastjson.JSON;
    import com.ljl.auth.model.*;
    import com.ljl.auth.service.UserService;
    import com.ljl.base.api.UserFeignApi;
    import com.ljl.common.base.Pages;
    import com.ljl.common.base.Result;
    import com.ljl.common.model.BaseOperator;
    import com.ljl.common.util.PasswordUtil;
    import com.ljl.common.util.StaticData;
    import com.ljl.dataSource.BaseDao;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.security.core.authority.AuthorityUtils;
    import org.springframework.security.core.userdetails.User;
    import org.springframework.security.core.userdetails.UserDetails;
    import org.springframework.security.core.userdetails.UsernameNotFoundException;
    import org.springframework.stereotype.Service;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpSession;
    import java.util.*;
    
    @Service("userService")
    public class UserServiceImpl implements UserService { 
        @Autowired
    	private UserFeignApi userFeignApi;
    
    	@Override
    	public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException { 
    		//查询用户信息
    		BaseOperator userinfo = userFeignApi.getUserByUsername(username);
    		//需要构造org.springframework.security.core.userdetails.User 对象包含账号密码还有用户的角色
    		if (userinfo!=null){ 
    			User user =  new User(userinfo.getLoginname(),userinfo.getPassword(), AuthorityUtils.createAuthorityList("admin"));
    			return new OauthUser(userinfo,user);
    		}else { 
    			throw  new UsernameNotFoundException("用户["+username+"]不存在");
    		}
    	}
    }

这个是我自己定义的实现了UserDetails, CredentialsContainer这两个接口的用户对象，除了再上面要用，jwt中也要用。  
这边的baseUser 是我自己的用户对象。

package com.ljl.auth.model;
    
    import com.ljl.common.model.BaseOperator;
    import org.springframework.security.core.CredentialsContainer;
    import org.springframework.security.core.GrantedAuthority;
    import org.springframework.security.core.userdetails.User;
    import org.springframework.security.core.userdetails.UserDetails;
    
    import java.util.Collection;
    
    /** * Created by Administrator on 2019/9/6 0006. */
    public class OauthUser implements UserDetails, CredentialsContainer { 
    
    
        private final BaseOperator baseUser;
        private final User user;
    
        public OauthUser(BaseOperator baseUser, User user) { 
            this.baseUser = baseUser;
            this.user = user;
        }
    
    
        @Override
        public void eraseCredentials() { 
            user.eraseCredentials();
        }
    
        @Override
        public Collection<? extends GrantedAuthority> getAuthorities() { 
            return user.getAuthorities();
        }
    
        @Override
        public String getPassword() { 
            return user.getPassword();
        }
    
        @Override
        public String getUsername() { 
            return user.getUsername();
        }
    
        @Override
        public boolean isAccountNonExpired() { 
            return user.isAccountNonExpired();
        }
    
        @Override
        public boolean isAccountNonLocked() { 
            return user.isAccountNonLocked();
        }
    
        @Override
        public boolean isCredentialsNonExpired() { 
            return user.isCredentialsNonExpired();
        }
    
        @Override
        public boolean isEnabled() { 
            return user.isEnabled();
        }
    
        public BaseOperator getBaseOperator() { 
            return baseUser;
        }
    }

## jwt ##

jwt生成token 我们可以自己定义jwt里面的内容

package com.ljl.auth.config;
    
    import com.ljl.auth.model.OauthUser;
    import org.springframework.security.oauth2.common.DefaultOAuth2AccessToken;
    import org.springframework.security.oauth2.common.OAuth2AccessToken;
    import org.springframework.security.oauth2.provider.OAuth2Authentication;
    import org.springframework.security.oauth2.provider.token.store.JwtAccessTokenConverter;
    
    import java.util.HashMap;
    
    /** * Created by Administrator on 2019/9/6 0006. * 自定义的token */
    public class MyJwtAccessTokenConverter extends JwtAccessTokenConverter { 
    
        @Override
        public OAuth2AccessToken enhance(OAuth2AccessToken accessToken, OAuth2Authentication authentication) { 
            if (accessToken instanceof DefaultOAuth2AccessToken) { 
                //((DefaultOAuth2AccessToken) accessToken).setRefreshToken();
                Object principal = authentication.getPrincipal();
                if (principal instanceof OauthUser) { 
                    OauthUser user = (OauthUser) principal;
                    HashMap<String, Object> map = new HashMap<>();
                    map.put("user_id", user.getBaseOperator().getUserid());
                    map.put("phone", user.getBaseOperator().getTelphonenum());
                    ((DefaultOAuth2AccessToken) accessToken).setAdditionalInformation(map);
                }
            }
            return super.enhance(accessToken, authentication);
        }
    
    
    }

RSA工具类

package com.ljl.common.util;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.core.io.ClassPathResource;
    import org.springframework.core.io.Resource;
    import org.springframework.util.Base64Utils;
    
    import javax.crypto.Cipher;
    import java.io.ByteArrayOutputStream;
    import java.io.FileNotFoundException;
    import java.io.FileOutputStream;
    import java.io.IOException;
    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.Base64;
    import java.util.Properties;
    
    /** * 实现RSA加解密 * @author : lijialun * @description: */
    public class RSAUtil { 
        private static final Logger LOGGER = LoggerFactory.getLogger(RSAUtil.class);
        /** 算法名称 */
        private static final String ALGORITHM =  "RSA";
        /** RSA签名算法 */
        private static final String RSA_SIGNATURE_ALGORITHM = "SHA256WithRSA";
        /** 默认密钥大小 */
        private static final int KEY_SIZE = 2048;
        /** 最大解密长度 */
        private static final int MAX_DECRYPT_BLOCK = 256;
        /** 用来指定保存密钥对的文件名和存储的名称 */
        private static final String PUBLIC_KEY_NAME = "publicKey";
        private static final String PRIVATE_KEY_NAME = "privateKey";
        private static final String PUBLIC_FILENAME = "publicKey.properties";
        private static final String PRIVATE_FILENAME = "privateKey.properties";
        private static Properties pubProperties;
        private static Properties PriProperties;
        /** 密钥对生成器 */
        private static KeyPairGenerator keyPairGenerator = null;
    
        private static KeyFactory keyFactory = null;
        /** 缓存的密钥对 */
        private static KeyPair keyPair = null;
        /** Base64 编码/解码器 JDK1.8 */
        private static Base64.Decoder decoder = Base64.getDecoder();
        private static Base64.Encoder encoder = Base64.getEncoder();
    
        /** 初始化密钥工厂 */
        static{ 
            try { 
                keyPairGenerator = KeyPairGenerator.getInstance(ALGORITHM);
                keyFactory = KeyFactory.getInstance(ALGORITHM);
                //generateKeyPair();
                getInstanceForPub();
                getInstanceForPri();
            } catch (NoSuchAlgorithmException e) { 
                LOGGER.error(e.getMessage(),e);
            }
        }
        /*初始化公钥config*/
        private static Properties getInstanceForPub(){ 
            if (pubProperties == null) { 
                Resource res  =new ClassPathResource(PUBLIC_FILENAME);
                pubProperties = new Properties();
                try { 
                    pubProperties.load(res.getInputStream());
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
            return pubProperties;
        }
        /*初始钥私钥config*/
        private static Properties getInstanceForPri(){ 
            if (PriProperties == null) { 
                Resource res  =new ClassPathResource(PRIVATE_FILENAME);
                PriProperties = new Properties();
                try { 
                    PriProperties.load(res.getInputStream());
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
            return PriProperties;
        }
        /** 私有构造器 */
        private RSAUtil(){ }
    
        /** * 生成密钥对 * 将密钥分别用Base64编码保存到#publicKey.properties#和#privateKey.properties#文件中 * 保存的默认名称分别为publicKey和privateKey * * */
        public static synchronized void generateKeyPair(){ 
            try { 
                keyPairGenerator.initialize(KEY_SIZE,new SecureRandom());
                keyPair = keyPairGenerator.generateKeyPair();
            } catch (InvalidParameterException e){ 
                LOGGER.error("KeyPairGenerator does not support a key length of " + KEY_SIZE + ".",e);
            } catch (NullPointerException e){ 
                LOGGER.error("RSAUtils#key_pair_gen is null,can not generate KeyPairGenerator instance.",e);
            }
            RSAPublicKey rsaPublicKey = (RSAPublicKey)keyPair.getPublic();
            RSAPrivateKey rsaPrivateKey = (RSAPrivateKey)keyPair.getPrivate();
            String publicKeyString = encoder.encodeToString(rsaPublicKey.getEncoded());
            String privateKeyString = encoder.encodeToString(rsaPrivateKey.getEncoded());
            System.out.println("公钥:"+publicKeyString);
            System.out.println("私钥:"+privateKeyString);
            storeKey(publicKeyString,PUBLIC_KEY_NAME,pubProperties,PUBLIC_FILENAME);
            storeKey(privateKeyString,PRIVATE_KEY_NAME,PriProperties,PRIVATE_FILENAME);
        }
    
        /** * 将指定的密钥字符串保存到文件中,如果找不到文件，就创建 * @param keyString 密钥的Base64编码字符串（值） * @param keyName 保存在文件中的名称（键） * @param properties 目标文件 */
        private static void storeKey(String keyString,String keyName,Properties properties,String fileName){ 
            try { 
                Resource res  =new ClassPathResource(fileName);
                FileOutputStream oFile = new FileOutputStream(res.getFile(), false);
                properties.setProperty(keyName,keyString);
                properties.store(oFile, keyName);
                oFile.close();
            } catch (FileNotFoundException e) { 
                e.printStackTrace();
            } catch (IOException e) { 
                e.printStackTrace();
            }
    
    
        }
    
        /** * 获取密钥字符串 * @param keyName 需要获取的密钥名 * @param properties 密钥文件 * @return Base64编码的密钥字符串 */
        private static String getKeyString(String keyName,Properties properties){ 
            return properties.getProperty(keyName);
        }
    
        /** * 从文件获取RSA公钥 * @return RSA公钥 * @throws InvalidKeySpecException */
        public static RSAPublicKey getPublicKey(){ 
            try { 
                byte[] keyBytes = decoder.decode(getKeyString(PUBLIC_KEY_NAME,pubProperties));
                X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(keyBytes);
                RSAPublicKey rsa = (RSAPublicKey)keyFactory.generatePublic(x509EncodedKeySpec);
                return rsa;
            }catch (InvalidKeySpecException e) { 
                LOGGER.error("getPublicKey()#" + e.getMessage(),e);
            }
            return null;
        }
    
        /** * 从文件获取RSA私钥 * @return RSA私钥 * @throws InvalidKeySpecException */
        public static RSAPrivateKey getPrivateKey(){ 
            try { 
                byte[] keyBytes = decoder.decode(getKeyString(PRIVATE_KEY_NAME,PriProperties));
                PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(keyBytes);
                return (RSAPrivateKey)keyFactory.generatePrivate(pkcs8EncodedKeySpec);
            } catch (InvalidKeySpecException e) { 
                LOGGER.error("getPrivateKey()#" + e.getMessage(),e);
            }
            return null;
        }
        /** * RSA公钥加密 */
        public static byte[] encryptByPublicKey(byte[] data) throws Exception { 
            // 对数据加密
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, getPublicKey());
            int inputLen = data.length;
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            int offSet = 0;
            byte[] cache;
            int i = 0;
            // 对数据分段加密
            while (inputLen - offSet > 0) { 
                if (inputLen - offSet > 117) { 
                    cache = cipher.doFinal(data, offSet, 117);
                } else { 
                    cache = cipher.doFinal(data, offSet, inputLen - offSet);
                }
                out.write(cache, 0, cache.length);
                i++;
                offSet = i * 117;
            }
            byte[] encryptedData = out.toByteArray();
            out.close();
            return encryptedData;
        }
    
        //私钥解密
        public static byte[] decryptByPrivateKey(byte[] encryptedData) throws Exception { 
            PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(getPrivateKey().getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
            Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
            cipher.init(Cipher.DECRYPT_MODE, privateK);
            int inputLen = encryptedData.length;
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            int offSet = 0;
            byte[] cache;
            int i = 0;
            // 对数据分段解密
            while (inputLen - offSet > 0) { 
                if (inputLen - offSet > MAX_DECRYPT_BLOCK) { 
                    cache = cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);
                } else { 
                    cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
                }
                out.write(cache, 0, cache.length);
                i++;
                offSet = i * MAX_DECRYPT_BLOCK;
            }
            byte[] decryptedData = out.toByteArray();
            out.close();
            return decryptedData;
        }
    
        /** * RSA公钥验签 * * @param data * 待签名字符串 * 公钥（Base64编码） * @return 验签结果 * @throws Exception */
        public static boolean verify(byte[] data, String sign) throws Exception { 
            Signature signature = Signature.getInstance(RSA_SIGNATURE_ALGORITHM);
            signature.initVerify(getPublicKey());
            signature.update(data);
            return signature.verify(Base64Utils.decodeFromUrlSafeString(sign));
        }
    
        /** * RSA私钥签名：签名方式SHA1withRSA * * @param data * 待签名byte[] * 私钥（Base64编码） * @return 签名byte[] * @throws Exception */
        public static byte[] sign(byte[] data) throws Exception { 
            // Sign
            Signature signature = Signature.getInstance(RSA_SIGNATURE_ALGORITHM);
            signature.initSign(getPrivateKey());
            signature.update(data);
            return signature.sign();
        }
    
    
    
        /** * 将char转换为byte * @param c char * @return byte */
        private static byte toByte(char c){ 
            return (byte)"0123456789ABCDEF".indexOf(c);
        }
    
    
        public static int getValidLength(byte[] bytes){ 
            int i = 0;
            if (null == bytes || 0 == bytes.length)
                return i ;
            for (; i < bytes.length; i++) { 
                if (bytes[i] == '\0')
                    break;
            }
            return i + 1;
        }
    
        public static KeyPair GetKeyPair(){ 
            return new KeyPair(getPublicKey(),getPrivateKey());
        }
    
    }