SpringBoot结合SpringSecurity实现图形验证码功能

本文介绍了SpringBoot结合SpringSecurity实现图形验证码功能，分享给大家，具体如下：

生成图形验证码

1. 根据随机数生成图片

2. 将随机数存到Session中

3. 将生成的图片写到接口的响应中

生成图形验证码的过程比较简单，和SpringSecurity也没有什么关系。所以就直接贴出代码了

根据随机数生成图片

/**
* 生成图形验证码
* @param request
* @return
*/
private ImageCode generate(ServletWebRequest request) {
int width = 64;
int height = 32;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

Graphics g = image.getGraphics();

Random random = new Random();

g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);
g.setFont(new Font("Times New Roman", Font.ITALIC, 20));
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 155; i++) {
 int x = random.nextInt(width);
 int y = random.nextInt(height);
 int xl = random.nextInt(12);
 int yl = random.nextInt(12);
 g.drawLine(x, y, x + xl, y + yl);
}

String sRand = "";
for (int i = 0; i < 4; i++) {
 String rand = String.valueOf(random.nextInt(10));
 sRand += rand;
 g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
 g.drawString(rand, 13 * i + 6, 16);
}

g.dispose();

return new ImageCode(image, sRand, 60);

}

/**
* 生成随机背景条纹
*
* @param fc
* @param bc
* @return
*/
private Color getRandColor(int fc, int bc) {
Random random = new Random();
if (fc > 255) {
 fc = 255;
}
if (bc > 255) {
 bc = 255;
}
int r = fc + random.nextInt(bc - fc);
int g = fc + random.nextInt(bc - fc);
int b = fc + random.nextInt(bc - fc);
return new Color(r, g, b);
}

将随机数存到Session中 && 将生成的图片写到接口的响应中

@RestController
public class ValidateCodeController {

public static final String SESSION_KEY = "SESSION_KEY_IMAGE_CODE";

private SessionStrategy sessionStrategy = new HttpSessionSessionStrategy();

@GetMapping("/code/image")
public void createCode(HttpServletRequest request, HttpServletResponse response) throws IOException {
 ImageCode imageCode = generate(new ServletWebRequest(request));
 sessionStrategy.setAttribute(new ServletWebRequest(request), SESSION_KEY, imageCode);
 ImageIO.write(imageCode.getImage(), "JPEG", response.getOutputStream());
}
}

在认证流程中加入图形验证码

在SpringSecurity认证流程详解中，我们有讲到，SpringSecurity是通过过滤器链来进行校验的，我们想要验证图形验证码，所以可以在认证流程之前，也就是UsernamePasswordAuthenticationFilter之前进行校验。

自定义图形验证码的过滤器

@Component
public class ValidateCodeFilter extends OncePerRequestFilter {

private SessionStrategy sessionStrategy = new HttpSessionSessionStrategy();

private AuthenticationFailureHandler authenticationFailureHandler;

@Override
protected void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws ServletException, IOException {
 if(StringUtils.equals("/user/login", httpServletRequest.getRequestURI())
   && StringUtils.equalsIgnoreCase(httpServletRequest.getMethod(), "post")) {

try {
   // 1. 进行验证码的校验
   validate(new ServletWebRequest(httpServletRequest));
  } catch (ValidateCodeException e) {
   // 2. 如果校验不通过，调用SpringSecurity的校验失败处理器
   authenticationFailureHandler.onAuthenticationFailure(httpServletRequest, httpServletResponse, e);
   return ;
  }
 }
 // 3. 校验通过，就放行
 filterChain.doFilter(httpServletRequest, httpServletResponse);
}
}

这里验证码校验的过程比较简单，主要就是判断传过来的参数和Session中保存的是否一致，以及Session中的验证码是否过期了。

有了自己的验证码过滤器之后，我们还需要将它配置在UsernamePasswordAuthenticationFilter之前：

@Override
protected void configure(HttpSecurity http) throws Exception {
ValidateCodeFilter validateCodeFilter = new ValidateCodeFilter();
validateCodeFilter.setAuthenticationFailureHandler(myAuthenticationFailureHandler);
// 将我们自定义的过滤器，配置到UsernamePasswordAuthenticationFilter之前
http.addFilterBefore(validateCodeFilter, UsernamePasswordAuthenticationFilter.class)
  .formLogin()     // 定义当需要用户登录时候，转到的登录页面。
  // 后面的配置省略
}    

代码下载

Spring-Security

来源：https://blog.csdn.net/u013435893/article/details/79617872