如何修复xss漏洞

[柯南8023]

package com.paic.cbps.filter;

import java.util.regex.Pattern;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import org.apache.commons.lang.StringUtils;

/**
 * 过滤 parameter 及 Header 中的特殊字符
 * @author EX-XIEJIANXIONG001
 * @Date: 2016年3月22日下午2:52:54
 */
public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {
	HttpServletRequest orgRequest = null;

	public XssHttpServletRequestWrapper(HttpServletRequest request) {
		super(request);
		orgRequest = request;
	}

	/**
	 * 覆盖 getParameter 方法，将参数名和参数值都做 xss 过滤。
	 * 如果需要获得原始的值，则通过 super.getParameterValues(name) 来获取
	 * getParameterNames，getParameterValues 和 getParameterMap 也可能需要覆盖
	 */
	@Override
	public String getParameter(String name) {
		String value = super.getParameter(xssEncode(name));
		if (value != null) {
			value = xssEncode(value);
		}
		
		return value;
	}

	/**
	 * 覆盖 getHeader 方法，将参数名和参数值都做 xss 过滤。
	 * 如果需要获得原始的值，则通过 super.getHeaders(name) 来获取
	 * getHeaderNames 也可能需要覆盖
	 */
	@Override
	public String getHeader(String name) {

		String value = super.getHeader(xssEncode(name));
		if (value != null) {
			value = xssEncode(value);
		}
		
		return value;
	}

/** 
    * 将容易引起xss漏洞的半角字符直接替换成全角字符 
    * 
    * @param s 
    * @return 
      
    private static String xssEncode(String s) {  
        if (s == null || "".equals(s)) {  
            return s;  
        }  
        StringBuilder sb = new StringBuilder(s.length() + 16);  
        for (int i = 0; i < s.length(); i++) {  
            char c = s.charAt(i);  
            switch (c) {  
            case '>':  
                sb.append('＞');//全角大于号  
                break;  
            case '<':  
                sb.append('＜');//全角小于号  
                break;  
            case '\'':  
                sb.append('‘');//全角单引号  
                break;  
            case '\"':  
                sb.append('“');//全角双引号  
                break;  
            case '&':  
                sb.append('＆');//全角  
                break;  
            case '\\':  
                sb.append('＼');//全角斜线  
                break;  
            case '#':  
                sb.append('＃');//全角井号  
                break;  
            default:  
                sb.append(c);  
                break;  
            }  
        }  
        return sb.toString();  
    }  */

	public String escape(String s) {
		StringBuilder sb = new StringBuilder(s.length() + 16);
		for (int i = 0; i < s.length(); i++) {
			char c = s.charAt(i);
			switch (c) {
			case '>':
				sb.append('＞');// 全角大于号
				break;
			case '<':
				sb.append('＜');// 全角小于号
				break;
			case '\'':
				sb.append('‘');// 全角单引号
				break;
			/*case '\"':
				sb.append('“');// 全角双引号
				break;*/
			case '\\':
				sb.append('＼');// 全角斜线
				break;
			case '%':
				sb.append('％'); // 全角冒号
				break;
			default:
				sb.append(c);
				break;
			}

		}
		
		return sb.toString();
	}

	/**
	 * 将容易引起xss漏洞的半角字符直接替换成全角字符
	 * 
	 * @param s
	 * @return
	 */
	public String xssEncode(String s) {
		if (s == null || s.isEmpty()) {
			return s;
		}

		String result = stripXSS(s);
		if (null != result) {
			result = escape(result);
		}

		return result;
	}

	private String stripXSS(String value) {
		if (StringUtils.isNotBlank(value)) {
			value = value.replaceAll("", "");
			// Avoid anything between script tags
			Pattern scriptPattern = Pattern.compile("<script>(.*?)</script>", Pattern.CASE_INSENSITIVE);
			value = scriptPattern.matcher(value).replaceAll("");
			// Avoid anything in a src='...' type of expression
			scriptPattern = Pattern.compile("src[\r\n]*=[\r\n]*\\\'(.*?)\\\'", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");
			scriptPattern = Pattern.compile("src[\r\n]*=[\r\n]*\\\"(.*?)\\\"", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");
			// Remove any lonesome </script> tag
			scriptPattern = Pattern.compile("</script>", Pattern.CASE_INSENSITIVE);
			value = scriptPattern.matcher(value).replaceAll("");
			// Remove any lonesome <script ...> tag
			scriptPattern = Pattern.compile("<script(.*?)>", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");
			// Avoid eval(...) expressions
			scriptPattern = Pattern.compile("eval\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");
			// Avoid expression(...) expressions
			scriptPattern = Pattern.compile("expression\\((.*?)\\)", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");
			// Avoid javascript:... expressions
			scriptPattern = Pattern.compile("javascript:", Pattern.CASE_INSENSITIVE);
			value = scriptPattern.matcher(value).replaceAll("");
			// Avoid vbscript:... expressions
			scriptPattern = Pattern.compile("vbscript:", Pattern.CASE_INSENSITIVE);
			value = scriptPattern.matcher(value).replaceAll("");
			// Avoid onload= expressions
			scriptPattern = Pattern.compile("onload(.*?)=", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");

			scriptPattern = Pattern.compile("<iframe>(.*?)</iframe>", Pattern.CASE_INSENSITIVE);
			value = scriptPattern.matcher(value).replaceAll("");

			scriptPattern = Pattern.compile("</iframe>", Pattern.CASE_INSENSITIVE);
			value = scriptPattern.matcher(value).replaceAll("");
			// Remove any lonesome <script ...> tag
			scriptPattern = Pattern.compile("<iframe(.*?)>", Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.DOTALL);
			value = scriptPattern.matcher(value).replaceAll("");
		}
		
		return value;
	}

	/**
	 * 获取最原始的request
	 * 
	 * @return
	 */
	public HttpServletRequest getOrgRequest() {
		return orgRequest;
	}

	/**
	 * 获取最原始的request的静态方法
	 * 
	 * @return
	 */
	public static HttpServletRequest getOrgRequest(HttpServletRequest req) {
		if (req instanceof XssHttpServletRequestWrapper) {
			return ((XssHttpServletRequestWrapper) req).getOrgRequest();
		}

		return req;
	}
}

[柯南8023]

新手小白，麻烦大神说的详细点，应该如何修改该漏洞

[Defonds]

半角的改成全角的就没事了。 楼主看看 http://www.owasp.org.cn/owasp-project/ESAPI/