锱铢必较：在spring boot中使用spring security的filter防止CSRF攻击

在一个spring boot项目中，需要防止CSRF攻击，按理说应该集成spring security才对。
但是不想使工程变得太复杂，这时可以只把spring security中的相关filter引入来进行。

在pom中添加相关依赖

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-freemarker</artifactId>
		</dependency>
		<!-- Security (used for CSRF protection only) -->
		<dependency>
			<groupId>org.springframework.security</groupId>
			<artifactId>spring-security-web</artifactId>
		</dependency>
	</dependencies>

在app启动时,添加CsrfFilter

@SpringBootApplication
public class Application extends WebMvcConfigurerAdapter {

	@Bean
	public FilterRegistrationBean csrfFilter() {
		FilterRegistrationBean registration = new FilterRegistrationBean();
		registration.setFilter(new CsrfFilter(new HttpSessionCsrfTokenRepository()));
		registration.addUrlPatterns("/*");
		return registration;
	}

	public static void main(String[] args) {
		SpringApplication.run(Application.class, args);
	}
}

form中添加CSRF的hidden字段

<input name="${(_csrf.parameterName)!}" value="${(_csrf.token)!}" type="hidden">

ajax中添加CSRF的头

xhr.setRequestHeader("${_csrf.headerName}", "${_csrf.token}");

demo地址是https://github.com/kabike/spring-boot-csrf