@WebFilter(urlPatterns = "/*", filterName = "sqlFilter")
@Configuration
public class SqlFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
throws IOException, ServletException {
ServletRequest request = servletRequest;
ServletResponse response = servletResponse;
// 获得所有请求参数名
Enumeration<String> names = request.getParameterNames();
String sql = "";
while (names.hasMoreElements()) {
// 得到参数名
String name = names.nextElement().toString();
// 得到参数对应值
String[] values = request.getParameterValues(name);
for (int i = 0; i < values.length; i++) {
sql += values[i];
}
}
if (sqlValidate(sql)) {
throw new IOException("您发送请求中的参数中含有非法字符");
} else {
filterChain.doFilter(request, response);
}
}
// 效验
protected static boolean sqlValidate(String str) {
String s = str.toLowerCase();// 统一转为小写
String badStr = "select|update|and|or|delete|insert|truncate|char|into|substr|ascii|declare|exec|count|master|into|drop|execute|table|"
+ "char|declare|sitename|xp_cmdshell|like|from|grant|use|group_concat|column_name|"
+ "information_schema.columns|table_schema|union|where|order|by|"
+ "'\\*|\\;|\\-|\\--|\\+|\\,|\\//|\\/|\\%|\\#";// 过滤掉的sql关键字,特殊字符前面需要加\\进行转义
// 使用正则表达式进行匹配
boolean matches = s.matches(badStr);
return matches;
}
@Override
public void destroy() {
}
}