shiro(3)shiro核心

身份认证

身份认证分三个步骤

1）提交主题和凭据

2）进行身份认证

3）判断是通过，重新提交还是不通过

验证顺序

1）调用subject的login方法，提交主体和凭据。

2）得到对应操作的Security Manager

3）通过Sceurity Manager得到对应的Autherticator实例

4）根据配置策略查找对应的桥信息

5）通过桥信息到对应的配置处理进行身份验证

验证器

如果你想配置一个自定义的验证器

可以在配置文件中使用

[main]
...
authenticator = com.foo.bar.CustomAuthenticator

securityManager.authenticator = $authenticator

配置策略信息

AtLeastOneSuccessfulStrategy 如果一个验证成功，则验证结果为成功

FirstSuccessfulStrategy         只有第一个成功，才算成功

AllSuccessfulStrategy            所有的都必须成功

对应的在配置文件中的策略使用如下

shiro.ini

[main]
...
authcStrategy = org.apache.shiro.authc.pam.FirstSuccessfulStrategy

securityManager.authenticator.authenticationStrategy = $authcStrategy

...

执行顺序

1）隐式顺序

blahRealm = com.company.blah.Realm
...
fooRealm = com.company.foo.Realm
...
barRealm = com.company.another.Realm

按上下顺序执行

2）指定顺序

blahRealm = com.company.blah.Realm
...
fooRealm = com.company.foo.Realm
...
barRealm = com.company.another.Realm

securityManager.realms = $fooRealm, $barRealm, $blahRealm
...

按指定的顺序执行

授权

控制谁有权限访问应用程序

授权的几个要素：权限，角色和用户。

三种权限的判断方式

1）编程

角色判断

Subject currentUser = SecurityUtils.getSubject();

if (currentUser.hasRole("administrator")) {
    //show the admin button
} else {
    //don't show the button?  Grey it out?
}

hasRole(String roleName)                            主题是否已分配给指定的角色

hasRoles(List<String> roleNames)                是否包含指定的角色

hasAllRoles(Collection<String> roleNames)   是否包含指定的所有角色

角色断言

Subject currentUser = SecurityUtils.getSubject();

//guarantee that the current user is a bank teller and
//therefore allowed to open the account:
currentUser.checkRole("bankTeller");
openBankAccount();

checkRole(String roleName)                       断言是否是指定角色

checkRoles(Collection<String> roleNames)  断言是否包含以下角色

checkRoles(String... roleNames)                断言是否包含所有角色

如果判断指定用户是否有权限访问指定名称的打印机

那么就会用到下列几个方法

Permission printPermission = new PrinterPermission("laserjet4400n", "print");

Subject currentUser = SecurityUtils.getSubject();

if (currentUser.isPermitted(printPermission)) {
    //show the Print button
} else {
    //don't show the button?  Grey it out?
}

isPermitted(Permission p) 判断主题是否允许执行一个动作

isPermitted(List<Permission> perms) 是否允许执行一组动作

isPermittedAll(Collection<Permission> perms) 是否允许执行所有动作

基于字符串的权限检查

Subject currentUser = SecurityUtils.getSubject();

if (currentUser.isPermitted("printer:print:laserjet4400n")) {
    //show the Print button
} else {
    //don't show the button?  Grey it out?
}

也可以如下使用

Subject currentUser = SecurityUtils.getSubject();

Permission p = new WildcardPermission("printer:print:laserjet4400n");

if (currentUser.isPermitted(p) {
    //show the Print button
} else {
    //don't show the button?  Grey it out?
}

权限断言类似于角色断言。

2）annocation方式

The RequiresAuthentication annotation

@RequiresAuthentication
public void updateAccount(Account userAccount) {
    //this method will only be invoked by a 
    //Subject that is guaranteed authenticated
    ...
}

等同于下述代码

public void updateAccount(Account userAccount) {
    if (!SecurityUtils.getSubject().isAuthenticated()) {
        throw new AuthorizationException(...);
    }
    
    //Subject is guaranteed authenticated here
    ...
}

The RequiresGuest annotation

@RequiresGuest
public void signUp(User newUser) {
    //this method will only be invoked by a 
    //Subject that is unknown/anonymous
    ...
}

等同于

public void signUp(User newUser) {
    Subject currentUser = SecurityUtils.getSubject();
    PrincipalCollection principals = currentUser.getPrincipals();
    if (principals != null && !principals.isEmpty()) {
        //known identity - not a guest:
        throw new AuthorizationException(...);
    }
    
    //Subject is guaranteed to be a 'guest' here
    ...
}

The RequiresPermissions annotation

@RequiresPermissions("account:create")
public void createAccount(Account account) {
    //this method will only be invoked by a Subject
    //that is permitted to create an account
    ...
}

等同于

public void createAccount(Account account) {
    Subject currentUser = SecurityUtils.getSubject();
    if (!subject.isPermitted("account:create")) {
        throw new AuthorizationException(...);
    }
    
    //Subject is guaranteed to be permitted here
    ...
}

The RequiresRoles permission

@RequiresRoles("administrator")
public void deleteUser(User user) {
    //this method will only be invoked by an administrator
    ...
}

等同于

public void deleteUser(User user) {
    Subject currentUser = SecurityUtils.getSubject();
    if (!subject.hasRole("administrator")) {
        throw new AuthorizationException(...);
    }
    
    //Subject is guaranteed to be an 'administrator' here
    ...
}

The RequiresUser annotation

@RequiresUser
public void updateAccount(Account account) {
    //this method will only be invoked by a 'user'
    //i.e. a Subject with a known identity
    ...
}

等同于

public void updateAccount(Account account) {
    Subject currentUser = SecurityUtils.getSubject();
    PrincipalCollection principals = currentUser.getPrincipals();
    if (principals == null || principals.isEmpty()) {
        //no identity - they're anonymous, not allowed:
        throw new AuthorizationException(...);
    }
    
    //Subject is guaranteed to have a known identity here
    ...
}

授权顺序

1）应用程序调用主题，判断hasRole,isPermitted得到角色或者用户权限的列表。

2）组成对应的授权方法

3）协调如何授权

4）通过桥进行各种方式的授权

web应用

配置web.xml

<listener>
    <listener-class>org.apache.shiro.web.env.EnvironmentLoaderListener</listener-class>
</listener>

...

<filter>
    <filter-name>ShiroFilter</filter-name>
    <filter-class>org.apache.shiro.web.servlet.ShiroFilter</filter-class>
</filter>

<filter-mapping>
    <filter-name>ShiroFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

如果你愿意你可以自定义一个web应用

<context-param>
    <param-name>shiroEnvironmentClass</param-name>
    <param-value>com.foo.bar.shiro.MyWebEnvironment</param-value>
</context-param>

如果你想改变shiro.ini的位置，那么你可以指定

<context-param>
    <param-name>shiroConfigLocations</param-name>
    <param-value>YOUR_RESOURCE_LOCATION_HERE</param-value>
</context-param>

shiro.ini中的[urls]配置

例如：

...
[urls]

/index.html = anon
/user/create = anon
/user/** = authc
/admin/** = authc, roles[administrator]
/rest/** = authc, rest
/remoting/rpc/** = authc, perms["remote:invoke"]

假如你有如下设置

/account/** = ssl, authc

/account下的任何应用程序都将触动ssl和authc链