标签：request cep web.xml class length count values 注入攻击 param
关于xss的介绍可以看 Asp.net安全架构之1：xss（跨站脚本）和 腾讯微博的XSS攻击漏洞 网页，
具体我就讲讲Spring MVC里面的预防：
web.xml加上：
|
1
2
3
4
|
<context-param>
<param-name>defaultHtmlEscape</param-name>
<param-value>true</param-value>
</context-param>
|
Forms加上：
|
1
|
<spring:htmlEscape defaultHtmlEscape="true" />
|
例如用户可以输入：
|
1
|
<script>alert();</script>
|
或者输入
|
1
|
<h2>abc<h2>
|
,如果有异常,显然有xss漏洞。
首先添加一个jar包:commons-lang-2.5.jar,然后在后台调用这些函数：
|
1
2
3
|
StringEscapeUtils.escapeHtml(string);
StringEscapeUtils.escapeJavaScript(string);
StringEscapeUtils.escapeSql(string);
|
前台js调用escape函数即可。
例如：< > ‘ “ \ / # &
方法是实现一个自定义的HttpServletRequestWrapper，然后在Filter里面调用它，替换掉getParameter函数即可。
首先添加一个XssHttpServletRequestWrapper:
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
package com.ibm.web.beans;
//
import java.util.Enumeration;
//
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
//
public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {
//
public XssHttpServletRequestWrapper(HttpServletRequest servletRequest) {
super(servletRequest);
}
//
public String[] getParameterValues(String parameter) {
String[] values = super.getParameterValues(parameter);
if (values==null) {
return null;
}
int count = values.length;
String[] encodedValues = new String[count];
for (int i = 0; i < count; i++) {
encodedValues[i] = cleanXSS(values[i]);
}
return encodedValues;
}
//
public String getParameter(String parameter) {
String value = super.getParameter(parameter);
if (value == null) {
return null;
}
return cleanXSS(value);
}
//
public String getHeader(String name) {
String value = super.getHeader(name);
if (value == null)
return null;
return cleanXSS(value);
}
//
private String cleanXSS(String value) {
//You‘ll need to remove the spaces from the html entities below
value = value.replaceAll("<", "& lt;").replaceAll(">", "& gt;");
value = value.replaceAll("\\(", "& #40;").replaceAll("\\)", "& #41;");
value = value.replaceAll("‘", "& #39;");
value = value.replaceAll("eval\\((.*)\\)", "");
value = value.replaceAll("[\\\"\\\‘][\\s]*javascript:(.*)[\\\"\\\‘]", "\"\"");
value = value.replaceAll("script", "");
return value;
}
}
|
然后添加一个过滤器XssFilter ：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
|
package com.ibm.web.beans;
//
import java.io.IOException;
//
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.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//
public class XssFilter implements Filter {
FilterConfig filterConfig = null;
//
public void init(FilterConfig filterConfig) throws ServletException {
this.filterConfig = filterConfig;
}
//
public void destroy() {
this.filterConfig = null;
}
//
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
chain.doFilter(new XssHttpServletRequestWrapper(
(HttpServletRequest) request), response);
}
}
|
最后在web.xml里面配置一下，所有的请求的getParameter会被替换，如果参数里面含有敏感词会被替换掉：
|
1
2
3
4
5
6
7
8
9
|
<filter>
<filter-name>XssSqlFilter</filter-name>
<filter-class>com.ibm.web.beans.XssFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>XssSqlFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
</filter-mapping>
|
(这个Filter也可以防止SQL注入攻击)
标签：request cep web.xml class length count values 注入攻击 param
原文地址：http://www.cnblogs.com/zousong/p/6748710.html
