防惡意攻擊之驗證碼生成Kaptcha 頭條網

2020-12-20 19:40:20 佚名

Kaptcha 簡介

Kaptcha 是一個可高度配置的實用驗證碼生成工具，可自由配置的選項如：

驗證碼的字體
驗證碼字體的大小
驗證碼字體的字體顏色
驗證碼內容的範圍(數字，字母，中文漢字！)
驗證碼圖片的大小，邊框，邊框粗細，邊框顏色
驗證碼的干擾線
驗證碼的樣式(魚眼樣式、3D、普通模糊、...)

主要代碼

KaptchaConfig.java

<code> 
public
 
class
 KaptchaConfig {
     
    
public
 DefaultKaptcha getDDefaultKaptcha
() {
        DefaultKaptcha dk = new DefaultKaptcha();
        Properties properties = new Properties();
         
        properties.setProperty("kaptcha.border"
, "yes");
         
        properties.setProperty("kaptcha.border.color"
, "105,179,90");
         
        properties.setProperty("kaptcha.textproducer.font.color"
, "red");
         
        properties.setProperty("kaptcha.image.width"
, "110");
         
        properties.setProperty("kaptcha.image.height"
, "40");
         
        properties.setProperty("kaptcha.textproducer.font.size"
, "30");
         
        properties.setProperty("kaptcha.session.key"
, "code");
         
        properties.setProperty("kaptcha.textproducer.char.length"
, "4");
         
        properties.setProperty("kaptcha.textproducer.font.names"
, "宋體,楷體,微軟雅黑");
        Config config = new Config(properties);
        dk.setConfig(config);

        return dk;
    }
}/<code>

控制器關鍵代碼

<code> 
public
 
class
 KaptchaController {
     
     
    DefaultKaptcha defaultKaptcha;

     
    public void defaultKaptcha(HttpServletRequest request, HttpServletResponse response) throws Exception {
        byte[] captcha = null;
        ByteArrayOutputStream out = new ByteArrayOutputStream();

        try {
             
            String createText = defaultKaptcha.createText();
            request.getSession().setAttribute("rightCode", createText);
            BufferedImage bi = defaultKaptcha.createImage(createText);
            ImageIO.write(bi, "jpg"
, out);
        } catch (Exception e) {
            response.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        }

        captcha = out.toByteArray();
        response.setHeader("Cache-Control"
, "no-store");
        response.setHeader("Pragma"
, "no-cache");
        response.setDateHeader("Expires"
, 0);
        response.setContentType("image/jpeg");
        ServletOutputStream sout = response.getOutputStream();
        sout.write(captcha);
        sout.flush();
        sout.close();
    }

     
     
    public ModelAndView imgvrifyControllerDefaultKaptcha(HttpServletRequest request, HttpServletResponse response) {
        ModelAndView model = new ModelAndView();
        String rightCode = (String) request.getSession().getAttribute("rightCode");
        String tryCode = request.getParameter("tryCode");
        System.out
.println("rightCode:"
 + rightCode + " ———— tryCode:" + tryCode);
        if (!rightCode.equals(tryCode)) {
            model.addObject("info"
, "驗證碼錯誤,請再輸一次!");
            model.setViewName("login");
        } else {
            model.addObject("info"
, "登陸成功");
            model.setViewName("index");
        }
        return model;
    }

     
     
    public ModelAndView index() {
        return
 new ModelAndView("login");
    }
}/<code>

前端頁面

<code> >
<
html
 xmlns:th
="http://www.thymeleaf.org">
<
head
 lang
="en">
<
meta
 charset
="UTF-8">
<
title
>Insert title here
title>
<
link
 rel
="stylesheet"
 href
="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/css/bootstrap.min.css">  
<
script
 src
="https://cdn.staticfile.org/jquery/2.1.1/jquery.min.js"
>
script>
<
script
 src
="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/js/bootstrap.min.js"
>
script>
<
style
 type
="text/css"
>
body {
    padding
: 10px;
}
#inputtext {
    width
: 100%;
}
#login{
    width
: 300px;
    margin
:0px auto;
    padding-top
: 60px;
}
#flushimg{
    text-decoration: underline;
}
#butt{
    width
: 60%;
}
style>
head>
<
body>
<
div
 id
="login">
    <
form
 action
="/login"
 method
="post">
        <
h2
 align
="center"
>L O G I N
h2
><
br
/><
br/>
        <
input
 type
="text"
 name
="userName"
 class
="form-control"
 id
="inputtext"
 required
 autofocus
 placeholder
="-----請輸入用戶名-----"
/><
br/>
        <
input
 type
="password"
 name
="userName"
 class
="form-control"
 id
="inputtext"
 required
 placeholder
="----請輸入用戶密碼----"
/><
br/>
        <
div
 id
="flushimg">
            <
img
 alt
="驗證碼"
 onclick
="this.src='/defaultKaptcha?d=' + new Date()*1"
 src
="/defaultKaptcha" />
            <
a
>看不清？點擊圖片刷新一下
a>
        
div> 
            <
input
 type
="text"
 name
="tryCode"
 class
="form-control"
 required
 placeholder
="-----請輸入驗證碼-----" />
            <
h4
 th:text
="${info}"
 style
="color: red"
>
h4>
            <
input
 type
="checkbox"
 name
="rememberMe"
/>記住我<
br/>
            <
div
 style
="width: 100%;text-align: center;"
><
input
 type
="submit"
 value
="登 錄"
 id
="butt"
 class
="btn btn-success"
 />
div>
    
form>
div>
body>
html
>/<code>