Java对html标签的过滤和清洗

OWASP HTML Sanitizer 是一个简单快捷的java类库，主要用于放置XSS

优点如下：

　　1.使用简单。不需要繁琐的xml配置，只用在代码中少量的编码

　　2.由Mike Samuel（谷歌工程师）维护

　　3.通过了AntiSamy超过95%的UT覆盖

　　4.高性能，低内存消耗

　　5.是 AntiSamy DOM性能的4倍

1.POM中增加

        <!--html标签过滤-->

        <dependency>

            <groupId>com.googlecode.owasp-java-html-sanitizer</groupId>

            <artifactId>owasp-java-html-sanitizer</artifactId>

            <version>r136</version>

        </dependency>

2.工具类

import org.owasp.html.ElementPolicy;

import org.owasp.html.HtmlPolicyBuilder;

import org.owasp.html.PolicyFactory;

import java.util.List;

/**

 * @author : RandySun

 * @date : 2018-10-08  10:32

 * Comment :

 */

public class HtmlUtils {

    //允许的标签

    private static final String[] allowedTags = {"h1", "h2", "h3", "h4", "h5", "h6",

            "span", "strong",

            "img", "video", "source",

            "blockquote", "p", "div",

            "ul", "ol", "li",

            "table", "thead", "caption", "tbody", "tr", "th", "td", "br",

            "a"

    };

    //需要转化的标签

    private static final String[] needTransformTags = {"article", "aside", "command","datalist","details","figcaption", "figure",

            "footer","header", "hgroup","section","summary"};

    //带有超链接的标签

    private static final String[] linkTags = {"img","video","source","a"};

    public static String sanitizeHtml(String htmlContent){

        PolicyFactory policy = new HtmlPolicyBuilder()

                //所有允许的标签

                .allowElements(allowedTags)

                //内容标签转化为div

                .allowElements( new ElementPolicy() {

                    @Override

                    public String apply(String elementName, List<String> attributes){

                        return "div";

                    }

                },needTransformTags)

                .allowAttributes("src","href","target").onElements(linkTags)

                //校验链接中的是否为http

                .allowUrlProtocols("https")

                .toFactory();

        String safeHTML = policy.sanitize(htmlContent);

        return safeHTML;

    }

    public static void main(String[] args){

        String inputHtml = "<img src=\"https://a.jpb\"/>";

        System.out.println(sanitizeHtml(inputHtml));

    }

}

　其中.allowElements(allowedTags)是添加所有允许的html标签，

以下是需要转化的标签，把needTransformTags中的内容全部转化为div

//内容标签转化为div
.allowElements( new ElementPolicy() {
    @Override
    public String apply(String elementName, List<String> attributes){
        return "div";
    }
},needTransformTags)

.allowAttributes("src","href","target").onElements(linkTags)是在特定的标签上允许的属性

.allowUrlProtocols("https")表示href或者src链接中只允许https协议