post:完成Spring Security基础文章。

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徐涛 2021-07-29 22:03:08 +08:00
parent fffdd03333
commit c30c88dfbd
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@startuml
skinparam Shadowing false
skinparam class {
BackgroundColor White
}
hide empty members
interface AuthenticationManager {
+ Authentication authenticate(Authentication authentication)
}
class ProviderManager {
- AuthenticationEventPublisher eventPublisher
- List<AuthenticationProvider> providers
- MessageSourceAccessor messages
- AuthenticationManager parent
- boolean eraseCredentialsAfterAuthentication
+ ProviderManager(AuthenticationProvider... providers)
+ ProviderManager(List<AuthenticationProvider> providers)
+ ProviderManager(List<AuthenticationProvider> providers, AuthenticationManager parent)
+ void afterPropertiesSet()
- void checkState()
- void copyDetails(Authentication source, Authentication dest)
+ List<AuthenticationProvider> getProviders()
+ void setMessageSource(MessageSource messageSource)
+ void setAuthenticationEventPublisher(AuthenticationEventPublisher eventPublisher)
+ void setEraeseCredentialsAfterAuthentication(boolean eraseSecretData)
+ boolean isEraseCredentialsAfterAuthentication()
}
class NullEventPublisher
interface AuthenticationEventPublisher {
+ void publishAuthenticationFailure(AuthenticationException exception, Authentication authentication)
+ void publishAuthenticationSuccess(Authentication authentication)
}
interface AuthenticationProvider {
+ Authentication authenticate(Authentication authentication)
+ boolean supports(Class<?> authentication)
}
abstract AbstractUserDetailsAuthenticationProvider {
# MessageSourceAccessor messages
- UserCache userCache
- boolean forcePrincipalAsString
- boolean hideUserNotFoundException
- UserDetailsChecker preAuthenticationChecks
- UserDetailsChecker postAuthenticationChecks
- GrantedAuthoritiesMapper authoritiesMapper
#{abstract} void additionalAuthenticationChecks(UserDetails userDetails, UsernamePasswordAuthenticationToken authentication)
+ void afterPropertiesSet()
- String determineUsername(Authentication authentication)
# Authentication createSuccessAuthentication(Object principal, Authentication authentication, UserDetails user)
# void doAfterPropertiesSet()
#{abstract} UserDetails retrieveUser(String username, UsernamePasswordAuthenticationToken authentication)
}
interface UserDetailsChecker {
+ void check(UserDetails toCheck)
}
class DefaultPreAuthenticationChecks
class DefaultPostAuthenticationChecks
interface UserCache {
+ UserDetails getUserFromCache(String username)
+ void putUserInCache(UserDetails user)
+ void removeUserFromCache(String username)
}
class UserDetails {
+ Collection<? extends GrantedAuthority> getAuthorities()
+ String getPassword()
+ String getUsername()
+ boolean isAccountNonExpired()
+ boolean isAccountNonLocked()
+ boolean isCredentialsNonExpired()
+ boolean isEnabled()
}
interface GrantedAuthoritiesMapper {
+ Collection<? extends GrantedAuthority> mapAuthorities(Collection<? extends GrantedAuthority> authorities)
}
interface GrantedAuthority {
+ String getAuthority()
}
class SimpleGrantedAuthority {
- String role
}
class SpringCacheBasedUserCache
class UsernamePasswordAuthenticationToken {
- Object principal
- Object credentials
}
abstract AbstractAuthenticationToken {
- Collection<GrantedAuthority> authorities
- Object details
- boolean authenticated
}
interface Authentication
interface CredentialsContainer {
+ void eraseCredentials()
}
AuthenticationManager <|.. ProviderManager
ProviderManager +-- NullEventPublisher
NullEventPublisher ..|> AuthenticationEventPublisher
AuthenticationProvider "1..*" --* "1" ProviderManager
AbstractUserDetailsAuthenticationProvider ..|> AuthenticationProvider
DefaultPreAuthenticationChecks --+ AbstractUserDetailsAuthenticationProvider
DefaultPostAuthenticationChecks --+ AbstractUserDetailsAuthenticationProvider
UserDetailsChecker <|.. DefaultPreAuthenticationChecks
UserDetailsChecker <|.. DefaultPostAuthenticationChecks
UserCache --* AbstractUserDetailsAuthenticationProvider
UserDetails --* AbstractUserDetailsAuthenticationProvider
UserDetails --* UserDetailsChecker
UserDetails --* UserCache
AbstractUserDetailsAuthenticationProvider *--- GrantedAuthoritiesMapper
GrantedAuthoritiesMapper *-- GrantedAuthority
GrantedAuthority <|.. SimpleGrantedAuthority
UserCache <|.. SpringCacheBasedUserCache
UsernamePasswordAuthenticationToken --* AbstractUserDetailsAuthenticationProvider
AbstractAuthenticationToken <|-- UsernamePasswordAuthenticationToken
Authentication <|.. AbstractAuthenticationToken
CredentialsContainer <|.. AbstractAuthenticationToken
@enduml

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@startuml
skinparam Shadowing false
skinparam class {
BackgroundColor White
}
hide empty members
package org.springframework.security.core {
package context {
class SecurityContextHolder {
-{static} SecurityContextHolderStrategy strategy
-{static} int initilizeCount
-{static} void initilize()
+{static} void clearContext()
+{static} SecurityContext getContext()
+{static} int getInitilizeCount()
+{static} void setContext(SecurityContext context)
+{static} void setStrategyName(String strategyName)
+{static} SecurityContextHolderStrategy getContextHolderStrategy()
+{static} SecurityContext createEmptyContext()
}
interface SecurityContextHolderStrategy {
+ void clearContext()
+ SecurityContext getContext()
+ void setContext(SecurityContext context)
+ SecurityContext createEmptyContext()
}
class ThreadLocalSecurityContextHolderStrategy {
-{static} ThreadLocal<SecurityContext> contextHolder
}
class GlobalSecurityContextHolderStrategy {
-{static} SecurityContext contextHolder
}
class InheritableThreadLocalSecurityContextHolderStrategy {
-{static} ThreadLocal<SecurityContext> contextHolder
}
class ReactiveSecurityContextHolder {
+{static} Mono<SecurityContext> getContext()
-{static} boolean hasSecurityContext(Context context)
-{static} Mono<SecurityContext> getSecurityContext(Context context)
+{static} Function<Context, Context> clearContext()
+{static} Context withSecurityContext(Mono<? extends SecurityContext> securityContext)
+{static} Context withAuthentication(Authentication authntication)
}
class SecurityContext {
+ Authentication getAuthentication()
+ void setAuthentication(Authentication authentication)
}
}
interface Authentication {
+ Collection<? extends GrantedAuthority> getAuthorities()
+ Object getCredentials()
+ Object getDetails()
+ Object getPrincipal()
+ boolean isAuthticated()
+ setAuthenticated(boolean isAuthenticated)
}
interface GrantedAuthority {
+ String getAuthority()
}
}
package java.security {
interface Principal {
+ String getName()
+ boolean implies(Subject subject)
}
}
SecurityContextHolderStrategy --* SecurityContextHolder
ThreadLocalSecurityContextHolderStrategy ..|> SecurityContextHolderStrategy
GlobalSecurityContextHolderStrategy ..|> SecurityContextHolderStrategy
InheritableThreadLocalSecurityContextHolderStrategy ...|> SecurityContextHolderStrategy
SecurityContext --* SecurityContextHolderStrategy
SecurityContext -* ReactiveSecurityContextHolder
SecurityContext --* ThreadLocalSecurityContextHolderStrategy
SecurityContext --* InheritableThreadLocalSecurityContextHolderStrategy
SecurityContext --* GlobalSecurityContextHolderStrategy
Authentication --* SecurityContext
GrantedAuthority -* Authentication
Authentication -|> Principal
@enduml

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@startuml
skinparam Shadowing false
skinparam class {
BackgroundColor White
}
hide empty members
abstract AbstractUserDetailsAuthenticationProvider
class UserDetails
class DaoAuthenticationProvider {
- PasswordEncoder passwordEncoder
- String userNotFoundEncodedPassword
- UserDetailsService userDetailsService
- UserDetailsPasswordService userDetailsPasswordService
- void prepareTimingAttackProtection()
- void mitigateAgainstTimingAttack(UsernamePasswordAuthenticationToken authentication)
}
interface UserDetailsService {
+ UserDetails loadUserByUsername(String username)
}
interface UserDetailsPasswordService {
+ UserDetails update(UserDetails user, String password)
}
interface PasswordEncoder {
+ String encode(CharSequence rawPassword)
+ boolean matches(CharSequence rawPassword, String encodedPassword)
+ boolean upgradeEncoding(String rawPassword)
}
class UsernamePasswordAuthenticationToken
abstract AbstractPasswordEncoder {
# byte[] encode(CharSequence rawPassword, byte[] salt)
# byte[] encodeAndConcatenate(CharSequence rawPassword, byte[] salt)
# {static} boolean matches(byte[] expected, byte[] actual)
}
class DelegatingPasswordEncoder {
- {static} String PREFIX
- {static} String SUFFIX
- String idForEncode
- PasswordEncoder passwordEncoderForEncode
- Map<String, PasswordEncoder> idToPasswordEncoder
- PasswordEncoder defaultPasswordEncoderForMatches
+ DelegatingPasswordEncoder(String idForEncode, Map<String, PasswordEncoder> idToPasswordEncoder)
+ void setDefaultPasswordEncoderForMatches(PasswordEncoder defaultPasswordEncoderForMatches)
- String extractId(String prefixEncodedPassword)
- String extractEncodedPassword(String prefixEncodedPassword)
}
class UnmappedIdPasswordEncoder
class BCryptPasswordEncoder
class Pbkdf2PasswordEncoder
DaoAuthenticationProvider --|> AbstractUserDetailsAuthenticationProvider
UserDetailsService --* DaoAuthenticationProvider
UserDetailsPasswordService --* DaoAuthenticationProvider
UsernamePasswordAuthenticationToken --* DaoAuthenticationProvider
PasswordEncoder ---* DaoAuthenticationProvider
UserDetails --* UserDetailsService
UserDetails --* UserDetailsPasswordService
AbstractPasswordEncoder ..|> PasswordEncoder
DelegatingPasswordEncoder ..|> PasswordEncoder
DelegatingPasswordEncoder +-- UnmappedIdPasswordEncoder
UnmappedIdPasswordEncoder ..|> PasswordEncoder
BCryptPasswordEncoder ..|> PasswordEncoder
Pbkdf2PasswordEncoder ..|> PasswordEncoder
@enduml

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@startdot spring-security-servlet-flow
digraph servlet {
rankdir=TB
edge [color="#A60738"]
node [color="#A60738"]
client [shape=box, label="客户端"]
servlet [shape=box, label="Servlet"]
tokenStorage [shape=box, label="令牌缓存"]
{ rank=same; tokenStorage; RememberMeServices }
client -> FilterChain [label="原始请求"]
FilterChain -> SecurityFilterChain [label="经过中转的请求"]
SecurityFilterChain -> UsernamePasswordAuthenticationProviderFilter [label="携带有用户名和密码的请求"]
UsernamePasswordAuthenticationProviderFilter -> AuthenticationManager [label="UsernamePasswordAuthenticationToken"]
AuthenticationManager -> SecurityContext [label="认证后的Authentication"]
SecurityFilterChain -> BearerTokenAuthenticationFilter [label="携带有Authorization头的请求"]
BearerTokenAuthenticationFilter -> AuthenticationManager [label="BearerTokenAuthenticationToken"]
AuthenticationManager -> DaoAuthenticationProvider [label="UsernamePasswordAuthenticationToken"]
DaoAuthenticationProvider -> UserDetailsService [label="UserDetails"]
UserDetailsService -> DaoAuthenticationProvider [label="认证后的UserDetails"]
DaoAuthenticationProvider -> PasswordEncoder [label="用户认证密码"]
PasswordEncoder -> DaoAuthenticationProvider [label="经过加密的密码"]
DaoAuthenticationProvider -> SecurityContext [label="认证后的Authentication"]
SecurityFilterChain -> RememberMeAuthenticationFilter [label="携带RememberMe认证的请求"]
RememberMeAuthenticationFilter -> RememberMeServices [label="RememberMeAuthenticationToken"]
RememberMeServices -> tokenStorage [label="认证令牌信息"]
RememberMeServices -> SecurityContext [label="认证后的Authentication"]
SecurityFilterChain -> AnonymousAuthenticationFilter [label="不携带任何认证信息请求"]
AnonymousAuthenticationFilter -> SecurityContext [label="匿名Authentication"]
SecurityContext -> servlet [label="已经加入认证信息的请求"]
}
@enddot

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@startdot spring-security-webflux-flow
digraph webfluxFlow {
rankdir=TB
edge [color="#A60738"]
node [color="#A60738"]
client [shape=box, label="客户端"]
endpoint [shape=box, label="处理端点"]
' tokenStorage [shape=box, label="令牌缓存"]
client -> SecurityFilterChain [label="HTTP请求"]
SecurityFilterChain -> AnonymousAuthenticationWebFilter [label="ServerWebExchange"]
AnonymousAuthenticationWebFilter -> SecurityContext [label="匿名Authentication"]
SecurityContext -> endpoint
SecurityFilterChain -> AuthenticationWebFilter [label="ServerWebExchange"]
AuthenticationWebFilter -> ReactivePreAuthenticatedAuthenticationManager [label="认证前的Authentication"]
ReactivePreAuthenticatedAuthenticationManager -> ReactiveUserDetailsService [label="用户认证信息"]
ReactiveUserDetailsService -> ReactivePreAuthenticatedAuthenticationManager [label="PreAuthenticatedAuthenticationToken"]
ReactivePreAuthenticatedAuthenticationManager -> AuthenticationWebFilter [label="PreAuthenticatedAuthenticationToken"]
AuthenticationWebFilter -> SecurityContext [label="认证后的Authentication"]
AuthenticationWebFilter -> JwtReactiveAuthenticationManager [label="认证前的Authentication"]
JwtReactiveAuthenticationManager -> AuthenticationWebFilter [label="BearerTokenAuthenticationToken"]
JwtReactiveAuthenticationManager -> JwtAuthenticationConverter [label="Jwt"]
JwtAuthenticationConverter -> JwtReactiveAuthenticationManager [label="JwtAuthenticationToken"]
}
@enddot

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---
title: Spring Security基础
tags:
- Java
- Spring
- Spring Security
- 安全认证
categories:
- - JVM
- Spring
keywords: 'Spring,Spring Security,UserDetails,SecurityContext'
date: 2021-07-29 21:59:41
---
Spring Security 是 Spring 框架中的安全框架,整个 Spring Security 在学习起来都是比较复杂的。这也是因为 Spring Security 在设计上所需要的组件比较多,所以比较难以理解。本文将尝试通过组成 Spring Securit 功能的常用功能组件以图的形式进行说明,以方便对于 Spring Security 能有一个比较清楚直观的理解。<!-- more -->
本篇关于 Spring Security 的文章主要由三部分组成,分别是:
1. {% post_link spring-security-basic %}
1. {% post_link spring-security-webmvc %}
1. {% post_link spring-security-webflux %}
## 基础组成
### SecurityContextHolder
在 Spring Security 中,`SecurityContextHolder`是 Spring Security 记录认证结果的核心。所有已经被认证过的用户都将被保存在`SecurityContextHolder`中。每个`SecurityContextHolder`实例中会利用一个`SecurityContextHolderStrategy`实例来保存已经完成验证的`SecurityContext`实例。
所以,在 Spring Security 中,每一个非空的`SecurityContextHolder`就代表着一个已经被认证过的用户,而且在 Spring Security 中,非空的`SecurityContextHolder`实例也常常被用来表示当前已经被认证过的用户。
以下是`SecurityContextHolder`系列接口的构成示意图。
{% oss_image spring-security/spring-security-cotnextholder.svg "SecurityContextHolder类结构图" %}
从这张图上可以看出,`SecurityContextHolder`中主要是利用其中的`SecurityContextHolderStrategy`实例来管理其中持有的`SecurityContext`实例。但是在实际使用时,我们并不需要直接调用`SecurityContextHolderStrategy`实例,只需要利用`SecurityContextHolder`来完成操作即可。
!!! note ""
如果想要在`SecurityContextHolder`中使用不同的策略实例,可以在配置文件中设定`spring.security.strategy`的值,这一配置项可以取以下三个值:`MODE_THREADLOCAL`、`MODE_INHERITABLETHREADLOCAL`、`MODE_GLOBAL`。在没有设置所需要使用的策略时,会默认采用`MODE_THREADLOCAL`。
### SpringContext
`SpringContext`类就比较简单了,根据上图描述,`SpringContext`里就是包含了一个`Authentication`接口实例。
### Authentication
`Authentication`接口是Spring Security中的认证功能核心在Spring Security中主要执行以下两个功能
1. 作为`AuthenticationManager`的输入数据来对用户进行认证。
1. 代表一个目前已经被认证的用户,在这种情况下,`Authentication`实例可以从`SecurityContext`中获得。
`Authentication`中通常会包含三种内容Principal、Credentials、Authorities。虽然在上图中Principal和Credentials都是`Object`类型的但Principal通常都是以`UserDetails`接口实例的形式出现而Credentials通常都是字符串。Authorities在上图中表示是一组`GrantedAuthority`实例,但是大部分情况下都是采用`SimpleGrantedAuthority`类包装的字符串组成Authorites集合。
### AuthenticationManager
`AuthenticationManager`在Spring Security中定义了如何执行用户身份验证经过`AuthenticationManager`的执行以后Spring Security即可以向`SecurityContextHolder`中写入被返回的验证信息。
!!! note ""
`AuthenticationManager`通常会被应用成一个Servlet Filter而这也是Spring Web MVC基于Servlet的处理流程。
由于`AuthenticationManager`只是一个接口,所以在实际使用时通常都使用`ProviderManager`类来实现其所定义的功能。常用的基于`AuthenticationManager`接口的类结构图如下。
{% oss_image spring-security/spring-secrutiy-authentication-manager.svg "AuthenticationManager类结构图" %}
从这张图上可以看出来,平时在使用`ProviderManager`的时候,实际上是在构建认证所需要的`AuthenticationProvider`。Spring Security提供了多个实现了`AuthenticationProvider`接口的抽象类,例如`AbstractUserDetailsAuthenticationProvider`,这些抽象类中实现了很多常用的功能,如果需要实现一个自定义`AuthenticationProvider`可以直接继承这些抽象类。Spring Security中也是基于这些抽象类提供了许多常见的认证场景支持。这些常用的认证类主要有以下几个。
1. `DaoAuthenticationProvider`,提供基于用户名和密码的认证。
1. `JwtAuthenticationProvider`提供基于JWT的认证。
1. `AnonymousAuthenticationProvider`,提供基于`AnonymousAuthenticationToken`的匿名用户认证。
1. `JaasAuthenticationProvider`提供基于Java认证与授权的认证。
1. `RemoteAuthenticationProvider`,提供远程认证。
1. `LdapAuthenticationProvider`提供基于LDAP的认证。
1. `OAuth2AuthenticationCodeAuthenticationProvider`提供基于授权码的OAuth 2.0认证。
1. `OAuth2LoginAuthenticationProvider`提供基于登录的OAuth 2.0认证。
1. `OpenIDAuthenticationProvider`提供基于OpenID授权的认证。
1. `PreAuthenticatedAuthenticationProvider`,提供基于预认证的授权认证。
1. `CasAuthenticationProvider`提供基于JA-SIG中央认证服务的授权认证。
1. `OpaqueTokenAuthenticationProvider`,提供基于不透明令牌的授权认证。
1. `JwtAuthenticationProvider`提供基于JWT的授权认证。
### DaoAuthenticationProvider
`DaoAuthenticationProvider`是Spring Security中最常用的Authentication Provider因为大部分认证场景都是基于用户名和密码的。`DaoAuthenticationProvider`进行认证功能的核心就是一个`UserDetailsService`实例,通过`UserDetailsService`可以完成用户提供的用户名和密码的验证,并且可以返回一个可供`Authentication`保存用户信息的`UserDetails`。
以下是`DaoAuthenticationProvider`的类结构图,在构建基于用户名和密码的认证过程中参考使用。
{% oss_image spring-security/spring-security-daoauthneticationprovider.svg DaoAuthenticationProvider类结构图 %}
### AbstractAuthenticationProcessingFilter
`AbstractAuthenticationProcessingFilter`继承了`GenericFilterBean`是Spring Servlet应用中Security相关过滤器定义的抽象类。基于Servlet的Web应用中一个请求在到达负责响应的Controller Bean之前需要经过数层过滤器的处理。`AbstractAuthenticationProcessingFilter`所执行的功能就是把Spring Security的认证与授权功能以过滤器的形式插入到Web请求的处理流程之中。
!!! note ""
在Spring Security的官方文档中对于过滤器的使用还提到了`DelegatingFilterProxy`和`FilterChainProxy`这两个代理类主要是用于在Servlet处理流程中插入Filter组合的在绝大多数情况下都不需要手动控制。在使用过程中一般只需要定义所需要使用的Filter即可。
对于`SecurityFilterChain`在整个Servlet请求处理流程中插入的Filter的先后顺序Spring Security官方文档是给了一个[列表](https://docs.spring.io/spring-security/site/docs/current/reference/html5/#servlet-security-filters)的可以直接参考使用。我们在日常使用过程中所需要关注的Filter主要有以下几个按调用顺序排列不一定全都使用
1. `CorsFilter`
1. `CsrfFilter`
1. `LogoutFilter`
1. `OAuth2AuthorizationRequestRedirectFilter`
1. `OAuth2LoginAuthenticationFilter`
1. `UsernamePasswordAuthenticationFilter`
1. `OpenIDAuthenticationFilter`
1. `BearerTokenAuthenticationFilter`
1. `RememberMeAuthenticationFilter`
1. `AnonymousAuthenticationFilter`
1. `OAuth2AuthorizationCodeGrantFilter`
1. `SessionManagementFilter`
1. `ExceptionTranslationFilter`
#### UsernamePasswordAuthenticationFilter
以`UsernamePasswordAuthenticationFilter`为例,它会将请求传入的用户名和密码整合放入`UsernamePasswordAuthenticationToken`中,这是一个实现了`Authentication`接口的类,主要用途就是存放用户认证信息。之后,`UsernamePasswordAuthenticaitonToken`实例就会被放入`AuthenticationManager`实例中进行认证。
所以在认证过程中所获取的`Authentication`接口实例,一般都是`UsernamePasswordAuthenticationToken`类的实例。
#### RememberMeAuthenticationFilter
`RememberMeAuthenticationFilter`可以主要用来提供已经完成认证的用户自动登录功能的过滤器,通过定义一个`RememberMeServices`接口或者`AbstractRememberMeServices`抽象类的实例,可以利用其中的`loginSuccess()`方法生成一个针对于已经完成认证的用户的记录这种记录可以是Token、Cookie或者其他任何形式。所生成的用户记录可以在下一次请求的`autoLogin()`方法中使用,并在请求中恢复认证记录。
#### BearerTokenAuthenticationFilter
`BearerTokenAuthenticaitonFilter`的主要功能就是解析HTTP请求头中的`Authorization`并将其中所携带的Token内容解析出来形成一个`BearerTokenAuthenticationToken`实例,然后放入`AuthenticationManager`中进行认证,最后将认证结果放入`SecurityContextHolder`中。这里出现的`BearerTokenAuthenticationToken`也是一个`AbstractAuthenticationToken`抽象类的子类,其中也包含了认证所需要使用的用户名、认证资料等。
## Spring Web MVC中的认证流程
Spring Web MVC中主要是依赖于Servlet Filter组成的管道来对HTTP请求中携带的认证消息进行处理。下面借用一个伪数据流图来简单示意一下在一次Web请求中认证信息的处理过程。
{% oss_image spring-security/spring-security-servlet-flow.svg "Spring Web MVC认证流程示意" %}
从这个图上可以看出来在Spring Web MVC中这些实现了`javax.servlet.Filter`的认证过滤器才是才是真正启动认证过程执行的起点。而我们在使用时大多只需要为它们提供它们所依赖的工作实例即可,例如`UserDetailsService`、`PasswordEncoder`等。
## Spring WebFlux中的认证流程
Spring WebFlux中的依赖的是WebFilter组成的过滤器管道来对HTTP请求中携带的认证消息进行处理。这里同样借用一个伪数据流图来进行简单的示意。
{% oss_image spring-security/spring-security-webflux-flow.svg "Spring WebFlux认证流程示意" %}
Spring WebFlux中的认证流程和参与组件要比Spring Web MVC少很多。从上图可以看出来启动认证过程的起点依旧是实现了`WebFilter`接口的过滤器,但是不同的认证过滤器开始使用不同的`AuthenticationManager`实例。但是整个流程中不变的是,所有已经完成认证的结果还都将保存到`SecurityContext`实例中。