1、核心依赖

        <dependency>

            <groupId>org.apache.shiro</groupId>

            <artifactId>shiro-core</artifactId>

            <version>1.4.0</version>

        </dependency>

2、认证流程：创建SecurityManager-->主体提交认证-->SecurityMananger认证-->Authentictor认证-->Realm验证（从subject.login(token)开始跟踪源码可以验证（idea下ctrl+alt+b跟踪源码）），单元测试代码如下：

package com.example.demo_mg;

import junit.framework.Assert;

import org.apache.shiro.SecurityUtils;

import org.apache.shiro.authc.UsernamePasswordToken;

import org.apache.shiro.mgt.DefaultSecurityManager;

import org.apache.shiro.realm.SimpleAccountRealm;

import org.apache.shiro.subject.Subject;

import org.junit.Before;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.boot.test.context.SpringBootTest;

import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)

@SpringBootTest

public class DemoMgApplicationTests {

    SimpleAccountRealm simpleAccountRealm = new SimpleAccountRealm();

    @Before

    public void before() {

        simpleAccountRealm.addAccount("wzs", "123456");

    }

    @Test

    public void contextLoads() {

    }

    @Test

    public void test() {

        //构建SecurityManager环境

        DefaultSecurityManager defaultSecurityManager = new DefaultSecurityManager();

        defaultSecurityManager.setRealm(simpleAccountRealm);

        //主体提交认证请求

        SecurityUtils.setSecurityManager(defaultSecurityManager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("wzs", "123456");

        subject.login(token);

        Assert.assertEquals(subject.isAuthenticated(), true);

        subject.logout();

        Assert.assertEquals(subject.isAuthenticated(), true);

    }

}

账号错误UnknownAccountException，密码错误IncorrectCredentialsException。

从subject.login(token);点击ctrl+alt+b跟踪源码到DelegatingSubject的login方法，调用Subject subject = this.securityManager.login(this, token);，继续跟踪到DefaultSecurityManager的login方法，调用info = this.authenticate(token);，继续跟踪到AuthenticatingSecurityManager的authenticate方法，调用this.authenticator.authenticate(token);，继续跟踪到AbstractAuthenticator的authenticate方法，调用info = this.doAuthenticate(token);，继续跟踪到ModularRealmAuthenticator的doAuthenticate方法，可以看到如下认证代码，通过realm实现认证：

    protected AuthenticationInfo doAuthenticate(AuthenticationToken authenticationToken) throws AuthenticationException {

        this.assertRealmsConfigured();

        Collection<Realm> realms = this.getRealms();

        return realms.size() == 1 ? this.doSingleRealmAuthentication((Realm)realms.iterator().next(), authenticationToken) : this.doMultiRealmAuthentication(realms, authenticationToken);

    }

3、授权流程：创建SecurityManager-->主体授权-->SecurityManager授权-->Authorizer授权-->Realm获取角色权限数据（数据库|缓存等）：

package com.example.demo_mg;

import org.apache.shiro.SecurityUtils;

import org.apache.shiro.authc.UsernamePasswordToken;

import org.apache.shiro.mgt.DefaultSecurityManager;

import org.apache.shiro.realm.SimpleAccountRealm;

import org.apache.shiro.subject.Subject;

import org.junit.Before;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.boot.test.context.SpringBootTest;

import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)

@SpringBootTest

public class DemoMgApplicationTests {

    SimpleAccountRealm simpleAccountRealm = new SimpleAccountRealm();

    @Before

    public void before() {

        simpleAccountRealm.addAccount("wzs", "123456", "admin", "user");

    }

    @Test

    public void contextLoads() {

    }

    @Test

    public void test() {

        //构建SecurityManager环境

        DefaultSecurityManager defaultSecurityManager = new DefaultSecurityManager();

        defaultSecurityManager.setRealm(simpleAccountRealm);

        //主体提交认证请求

        SecurityUtils.setSecurityManager(defaultSecurityManager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("wzs", "123456");

        subject.login(token);

        //授权

        subject.checkRole("admin");

        subject.checkRoles("admin", "user");

        subject.logout();

    }

}

角色不存在UnauthorizedException

从subject.checkRoles("admin", "user");点击ctrl+alt+b跟踪源码到DelegatingSubject的checkRoles方法，调用this.securityManager.checkRoles(this.getPrincipals(), roleIdentifiers);，继续跟踪到AuthorizingSecurityManager的checkRoles方法，调用this.authorizer.checkRoles(principals, roles);，继续跟踪到ModularRealmAuthorizer的checkRoles方法，遍历roles调用this.checkRole(principals, role);，继续跟踪到checkRole方法，调用this.hasRole(principals, role)，继续跟踪到hasRole方法，可见如下代码，通过realm授权：

    public boolean hasRole(PrincipalCollection principals, String roleIdentifier) {

        this.assertRealmsConfigured();

        Iterator var3 = this.getRealms().iterator();

        Realm realm;

        do {

            if (!var3.hasNext()) {

                return false;

            }

            realm = (Realm)var3.next();

        } while(!(realm instanceof Authorizer) || !((Authorizer)realm).hasRole(principals, roleIdentifier));

        return true;

    }

4、测试内置的IniRealm：

在src/test下新建Direcotry，名称resources，右键Mark Direcotry As-->Test Sources Root，在下面新建user.ini文件，内容：

[users]

wzs=123456,admin

[roles]

admin=user:delete,user:update

单元测试代码：

package com.example.demo_mg;

import org.apache.shiro.SecurityUtils;

import org.apache.shiro.authc.UsernamePasswordToken;

import org.apache.shiro.mgt.DefaultSecurityManager;

import org.apache.shiro.realm.text.IniRealm;

import org.apache.shiro.subject.Subject;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.boot.test.context.SpringBootTest;

import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)

@SpringBootTest

public class DemoMgApplicationTests {

    @Test

    public void contextLoads() {

    }

    @Test

    public void test() {

        IniRealm iniRealm = new IniRealm("classpath:user.ini");

        //构建SecurityManager环境

        DefaultSecurityManager defaultSecurityManager = new DefaultSecurityManager();

        defaultSecurityManager.setRealm(iniRealm);

        //主体提交认证请求

        SecurityUtils.setSecurityManager(defaultSecurityManager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("wzs", "123456");

        subject.login(token);

        //授权

        subject.checkRole("admin");

        subject.checkPermissions("user:delete", "user:update");

        subject.checkPermission("user:insert");

        subject.logout();

    }

}

权限不存在UnauthorizedException

5、测试内置的JdbcRealm：

1）安装mysql8.0

2）按照JdbcRealm的源码的SQL建表：

CREATE TABLE `users` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `username` varchar(255) DEFAULT NULL,

  `password` varchar(255) DEFAULT NULL,

`password_salt` varchar(255) DEFAULT NULL,

  PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=latin1;

CREATE TABLE `user_roles` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `username` varchar(255) DEFAULT NULL,

  `role_name` varchar(255) DEFAULT NULL,

  PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=latin1;

CREATE TABLE `roles_permissions` (

  `id` int(11) NOT NULL AUTO_INCREMENT,

  `role_name` varchar(255) DEFAULT NULL,

  `permission` varchar(255) DEFAULT NULL,

  PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=latin1;

3）添加测试数据：

insert into users (username,password) values ('wzs','123456');

insert into user_roles (username,role_name) values ('wzs','admin');

insert into roles_permissions (role_name,permission) values ('admin','user:delete');

4）依赖

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

            <version>8.0.11</version>

        </dependency>

        <dependency>

            <groupId>com.alibaba</groupId>

            <artifactId>druid</artifactId>

            <version>1.1.6</version>

        </dependency>

5）单元测试代码：

package com.example.demo_mg;

import com.alibaba.druid.pool.DruidDataSource;

import org.apache.shiro.SecurityUtils;

import org.apache.shiro.authc.UsernamePasswordToken;

import org.apache.shiro.mgt.DefaultSecurityManager;

import org.apache.shiro.realm.jdbc.JdbcRealm;

import org.apache.shiro.realm.text.IniRealm;

import org.apache.shiro.subject.Subject;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.boot.test.context.SpringBootTest;

import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)

@SpringBootTest

public class DemoMgApplicationTests {

    DruidDataSource dataSource = new DruidDataSource();

    {

        dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");

        dataSource.setUrl("jdbc:mysql://129.204.58.30:3306/shiro");

        dataSource.setUsername("user");

        dataSource.setPassword("*********");

    }

    @Test

    public void contextLoads() {

    }

    @Test

    public void test() {

        JdbcRealm jdbcRealm = new JdbcRealm();

        jdbcRealm.setDataSource(dataSource);

        jdbcRealm.setPermissionsLookupEnabled(true);//为了查询权限表，要开启权限查询

        //构建SecurityManager环境

        DefaultSecurityManager defaultSecurityManager = new DefaultSecurityManager();

        defaultSecurityManager.setRealm(jdbcRealm);

        //主体提交认证请求

        SecurityUtils.setSecurityManager(defaultSecurityManager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("wzs", "123456");

        subject.login(token);

        //授权

        System.out.println(subject.isAuthenticated());

        System.out.println(subject.hasRole("admin"));

        System.out.println(subject.isPermitted("user:delete"));

        subject.logout();

    }

}

6）若自定义用户、角色、权限三张表，需要自定义查询用户、角色、权限的SQL：

参考JdbcRealm的查询语句：

    protected String authenticationQuery = "select password from users where username = ?";

    protected String userRolesQuery = "select role_name from user_roles where username = ?";

    protected String permissionsQuery = "select permission from roles_permissions where role_name = ?";

设置自定义查询语句到jdbcRealm对象：

        jdbcRealm.setAuthenticationQuery("自定义查询用户sql");

        jdbcRealm.setUserRolesQuery("自定义查询角色sql");

        jdbcRealm.setPermissionsQuery("自定义查询权限sql");

6、自定义Realm，参考JdbcRealm继承抽象的AuthorizingRealm类并实现其抽象方法，认证doGetAuthenticationInfo，授权doGetAuthenticationInfo，然后单元测试授权和认证：

package com.example.demo_mg.realm;

import org.apache.commons.collections.map.HashedMap;

import org.apache.shiro.authc.AuthenticationException;

import org.apache.shiro.authc.AuthenticationInfo;

import org.apache.shiro.authc.AuthenticationToken;

import org.apache.shiro.authc.SimpleAuthenticationInfo;

import org.apache.shiro.authz.AuthorizationInfo;

import org.apache.shiro.authz.SimpleAuthorizationInfo;

import org.apache.shiro.realm.AuthorizingRealm;

import org.apache.shiro.subject.PrincipalCollection;

import java.util.*;

public class TestRealm extends AuthorizingRealm {

    //模拟users、user_roles、roles_permissions三张表的查询，实际应用需要查询数据库或缓存

    Map<String, String> users = new HashMap<>();

    Map<String, Set<String>> user_roles = new HashedMap();

    Map<String, Set<String>> roles_permissions = new HashedMap();

    {

        users.put("wzs", "123456");

        user_roles.put("wzs", new HashSet<>(Arrays.asList("admin", "test")));

        roles_permissions.put("admin", new HashSet<>(Arrays.asList("user:delete", "user:update")));

        super.setName("TestRealm"); //设置Realm名称，可选

    }

    @Override

    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principalCollection) {

        //从认证信息获取用户名

        String username = (String)principalCollection.getPrimaryPrincipal();

        //从数据库或缓存中获取角色、权限数据

        Set<String> roles = user_roles.get(username);

        Set<String> permissions = new HashSet<>();

        for (String role : roles) {

            Set<String> set;

            if((set = roles_permissions.get(role)) != null) {

                permissions.addAll(set);

            }

        }

        SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();

        simpleAuthorizationInfo.setRoles(roles);

        simpleAuthorizationInfo.setStringPermissions(permissions);

        return simpleAuthorizationInfo;

    }

    @Override

    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken authenticationToken) throws AuthenticationException {

        //从主题传过来的认证信息中，获得用户名

        String username = (String)authenticationToken.getPrincipal();

        //通过用户名从数据库中获取凭证

        String password = users.get(username);

        if(password != null) {

            return new SimpleAuthenticationInfo(username, password, super.getName());

        }

        return null;

    }

}

单元测试：

package com.example.demo_mg;

import com.example.demo_mg.realm.TestRealm;

import org.apache.shiro.SecurityUtils;

import org.apache.shiro.authc.UsernamePasswordToken;

import org.apache.shiro.mgt.DefaultSecurityManager;

import org.apache.shiro.subject.Subject;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.boot.test.context.SpringBootTest;

import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)

@SpringBootTest

public class DemoMgApplicationTests {

    @Test

    public void contextLoads() {

    }

    @Test

    public void test() {

        TestRealm testRealm = new TestRealm();

        //构建SecurityManager环境

        DefaultSecurityManager defaultSecurityManager = new DefaultSecurityManager();

        defaultSecurityManager.setRealm(testRealm);

        //主体提交认证请求

        SecurityUtils.setSecurityManager(defaultSecurityManager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("wzs", "123456");

        subject.login(token);

        //授权

        System.out.println(subject.isAuthenticated());

        System.out.println(subject.hasRole("admin"));

        System.out.println(subject.isPermitted("user:delete"));

        subject.logout();

    }

}

7、密码加密及加盐：

在6的基础上调整代码：

package com.example.demo_mg.realm;

import org.apache.commons.collections.map.HashedMap;

import org.apache.shiro.authc.AuthenticationException;

import org.apache.shiro.authc.AuthenticationInfo;

import org.apache.shiro.authc.AuthenticationToken;

import org.apache.shiro.authc.SimpleAuthenticationInfo;

import org.apache.shiro.authz.AuthorizationInfo;

import org.apache.shiro.authz.SimpleAuthorizationInfo;

import org.apache.shiro.crypto.hash.Md5Hash;

import org.apache.shiro.realm.AuthorizingRealm;

import org.apache.shiro.subject.PrincipalCollection;

import org.apache.shiro.util.ByteSource;

import java.util.*;

public class TestRealm extends AuthorizingRealm {

    //模拟users、user_roles、roles_permissions三张表的查询，实际应用需要查询数据库或缓存

    Map<String, String> users = new HashMap<>();

    Map<String, Set<String>> user_roles = new HashedMap();

    Map<String, Set<String>> roles_permissions = new HashedMap();

    String salt = UUID.randomUUID().toString().replaceAll("-","");

    {

        //不加盐(与认证对应）

//        users.put("wzs", new Md5Hash("123456",null, 2).toString());

        //加盐

        users.put("wzs", new Md5Hash("123456",salt, 2).toString());

        user_roles.put("wzs", new HashSet<>(Arrays.asList("admin", "test")));

        roles_permissions.put("admin", new HashSet<>(Arrays.asList("user:delete", "user:update")));

        super.setName("TestRealm"); //设置Realm名称，可选

    }

    @Override

    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principalCollection) {

        //从认证信息获取用户名

        String username = (String)principalCollection.getPrimaryPrincipal();

        //从数据库或缓存中获取角色、权限数据

        Set<String> roles = user_roles.get(username);

        Set<String> permissions = new HashSet<>();

        for (String role : roles) {

            Set<String> set;

            if((set = roles_permissions.get(role)) != null) {

                permissions.addAll(set);

            }

        }

        SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();

        simpleAuthorizationInfo.setRoles(roles);

        simpleAuthorizationInfo.setStringPermissions(permissions);

        return simpleAuthorizationInfo;

    }

    @Override

    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken authenticationToken) throws AuthenticationException {

        //从主题传过来的认证信息中，获得用户名

        String username = (String)authenticationToken.getPrincipal();

        //通过用户名从数据库中获取凭证

        String password = users.get(username);

        if(password != null) {

            //不加盐

//            return new SimpleAuthenticationInfo(username, password, super.getName());

            //加盐

            SimpleAuthenticationInfo simpleAuthenticationInfo = new SimpleAuthenticationInfo(username, password, super.getName());

            simpleAuthenticationInfo.setCredentialsSalt(ByteSource.Util.bytes(salt));

            return simpleAuthenticationInfo;

        }

        return null;

    }

}

单元测试：

package com.example.demo_mg;

import com.example.demo_mg.realm.TestRealm;

import org.apache.shiro.SecurityUtils;

import org.apache.shiro.authc.UsernamePasswordToken;

import org.apache.shiro.authc.credential.HashedCredentialsMatcher;

import org.apache.shiro.mgt.DefaultSecurityManager;

import org.apache.shiro.subject.Subject;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.springframework.boot.test.context.SpringBootTest;

import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)

@SpringBootTest

public class DemoMgApplicationTests {

    @Test

    public void contextLoads() {

    }

    @Test

    public void test() {

        TestRealm testRealm = new TestRealm();

        //设置加密

        HashedCredentialsMatcher matcher = new HashedCredentialsMatcher();

        matcher.setHashAlgorithmName("md5"); //加密算法

        matcher.setHashIterations(2); //加密次数，与new Md5Hash("123456",null, 2).toString();的hashIterations参数一致，否则IncorrectCredentialsException

        testRealm.setCredentialsMatcher(matcher);

        //构建SecurityManager环境

        DefaultSecurityManager defaultSecurityManager = new DefaultSecurityManager();

        defaultSecurityManager.setRealm(testRealm);

        //主体提交认证请求

        SecurityUtils.setSecurityManager(defaultSecurityManager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("wzs", "123456");

        subject.login(token);

        //授权

        System.out.println(subject.isAuthenticated());

        System.out.println(subject.hasRole("admin"));

        System.out.println(subject.isPermitted("user:delete"));

        subject.logout();

    }

}

MD5加密不可逆，但不加盐存在风险，注册的时候随机生成盐，保存到数据库，这里返回的认证对象带的盐从库里查出来。

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