项目中配置防止sql注入(springboot)

在项目中我们经常会遇到这些sql注入的问题，这边我介绍的是通过filter拦截的方式进行过滤一些sql脚本的注入，在平时编程的时候我们也要注意，在程序中编写sql脚本(mapper.xml) 文件的时候能用#尽量用#，避免一个恶意攻击网站的人。

首先介绍一下#和$的区别：

1. #{}：占位符号，好处防止sql注入，自带单引号变量
2. ${}：sql拼接符号，原生变量

接下来介绍写在java项目中(springboot)如何通过webFilter防止sql注入：

/**
 * sql注入过滤器
 */
@Component
@WebFilter(urlPatterns = "/*", filterName = "SQLInjection", initParams = { @WebInitParam(name = "regx", value = "(?:')|(?:--)|(/\\*(?:.|[\\n\\r])*?\\*/)|" +
 "(\\b(select|update|and|or|delete|insert|trancate|char|into|substr|ascii|declare|exec|count|master|into|drop|execute)\\b)") })
public class SqlInjectFilter implements Filter{
    private String regx;
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        this.regx = filterConfig.getInitParameter("regx");
    }
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) servletRequest;
        Map parametersMap = servletRequest.getParameterMap();
        Iterator it = parametersMap.entrySet().iterator();
        while (it.hasNext()) {
            Map.Entry entry = (Map.Entry) it.next();
            String[] value = (String[]) entry.getValue();
            for (int i = 0; i < value.length; i++) {
                if (null != value[i] && value[i].matches(this.regx)) {
                    log.error("您输入的参数有非法字符，请输入正确的参数！");
                    servletRequest.setAttribute("err", "您输入的参数有非法字符，请输入正确的参数！");
                    servletRequest.setAttribute("pageUrl",req.getRequestURI());
                    servletRequest.getRequestDispatcher(servletRequest.getServletContext().getContextPath() + "/error").forward(servletRequest, servletResponse);
                    return;
                }
            }
        }
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {

    }
}

完~

哦，对了，启动类上记得加注解：

@ServletComponentScan(basePackages ="xxxx.xxx.xxx.filter") //filter所在的包，扫描