跨站點請求偽造 - SpringBoot配置CSRF過濾器

1. 跨站點請求偽造

  風險：可能會竊取或操縱客戶會話和 cookie，它們可能用於模仿合法用戶，從而使黑客能夠以該用戶身份查看或變更用戶記錄以及執行事務。
  原因：應用程序使用的認證方法不充分。
  固定值：驗證“Referer”頭的值，並對每個提交的表單使用 one-time-nonce。

2. pom.xml添加依賴

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-configuration-processor</artifactId>
	<optional>true</optional>
</dependency>

3. 配置文件添加配置

# 信息安全
security:
  csrf:
    enable: true
    excludes:

4. 添加CSRF過濾器

import java.io.IOException;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

import lombok.extern.slf4j.Slf4j;

/**
 * CSRF過濾器
 * 
 * @author CL
 *
 */
@Slf4j
@Component
@ConfigurationProperties(prefix = "security.csrf")
@WebFilter(filterName = "CsrfFilter", urlPatterns = "/*")
public class CsrfFilter implements Filter {

	/**
	 * 過濾器配置對象
	 */
	FilterConfig filterConfig = null;

	/**
	 * 是否啟用
	 */
	private boolean enable;

	public void setEnable(boolean enable) {
		this.enable = enable;
	}

	/**
	 * 忽略的URL
	 */
	private List<String> excludes;

	public void setExcludes(List<String> excludes) {
		this.excludes = excludes;
	}

	/**
	 * 初始化
	 */
	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		this.filterConfig = filterConfig;
	}

	/**
	 * 攔截
	 */
	@Override
	public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
			throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest) servletRequest;

		// 不啟用或者已忽略的URL不攔截
		if (!enable || isExcludeUrl(request.getServletPath())) {
			filterChain.doFilter(servletRequest, servletResponse);
			return;
		}

		String referer = request.getHeader("Referer");
		String serverName = request.getServerName();

		// 判斷是否存在外鏈請求本站
		if (null != referer && referer.indexOf(serverName) < 0) {
			log.error("CSRF過濾器 => 服務器：{} => 當前域名：{}", serverName, referer);
			servletResponse.setContentType("text/html; charset=utf-8");
			servletResponse.getWriter().write("系統不支持當前域名的訪問！");
		} else {
			filterChain.doFilter(servletRequest, servletResponse);
		}
	}

	/**
	 * 銷毀
	 */
	@Override
	public void destroy() {
		this.filterConfig = null;
	}

	/**
	 * 判斷是否為忽略的URL
	 * 
	 * @param urlPath URL路徑
	 * @return true-忽略，false-過濾
	 */
	private boolean isExcludeUrl(String url) {
		if (excludes == null || excludes.isEmpty()) {
			return false;
		}
		return excludes.stream().map(pattern -> Pattern.compile("^" + pattern)).map(p -> p.matcher(url))
				.anyMatch(Matcher::find);
	}
}