使用Nginx+Lua实现waf

Posted 2021-01-23 叨客厨子

使用nginx+Lua实现waf

技术内容来自：https://github.com/loveshell/ngx_lua_waf

软件包需求：
1 .Nginx兼容性【最后测试到1.13.6】

[[email protected] src]# wget http://nginx.org/download/nginx-1.13.6.tar.gz

2 .PCRE为Nginx编译安装关系的依赖

[[email protected] src]# wget https://jaist.dl.sourceforge.net/project/pcre/pcre/8.42/pcre-8.42.tar.gz

3 .下载luajit解释器和ngx_devel_kit以及lua-nginx-module模块

[[email protected] src]# wget http://luajit.org/download/LuaJIT-2.0.5.tar.gz
[[email protected] src]# wget https://github.com/simplresty/ngx_devel_kit/archive/v0.3.0.tar.gz
[[email protected] src]# wget https://github.com/openresty/lua-nginx-module/archive/v0.10.13.tar.gz

4 .文件解压：

[[email protected] src]# tar xf nginx-1.13.6.tar.gz pcre-8.42.tar.gz LuaJIT-2.0.5.tar.gz v0.3.0.tar.gz v0.10.13.tar.gz

5 .安装LuaJIT Luajit是Lua即时编译器

[[email protected] src]# cd LuaJIT-2.0.5/
[[email protected] LuaJIT-2.0.5]# make && make install 

6 .添加环境变量

[[email protected] src]# export LUAJIT_LIB=/usr/local/lib
[[email protected] src]# export LUAJIT_INC=/usr/local/include/luajit-2.0

7 .安装Nginx并加载模块【注意目录位置以及版本】

• --prefix=/usr/local/nginx-1.13.6 # nginx 安装目录
• --with-pcre=/usr/local/src/pcre-8.42 # pcre 所在目录
• --add-module=../ngx_devel_kit-0.3.0/ # ngx_devel_kit 所在目录
• --add-module=../lua-nginx-module-0.10.13/ # lua-nginx-module 所在目录
• -j2 调用编译CPU的核数

[[email protected] src]# cd nginx-1.13.6/
[[email protected] nginx-1.13.6]# ./configure --user=www --group=www --prefix=/usr/local/nginx-1.13.6 --with-pcre=/usr/local/src/pcre-8.42 --with-http_stub_status_module --with-http_sub_module --with-http_gzip_static_module --without-mail_pop3_module --without-mail_imap_module --without-mail_smtp_module  --add-module=../ngx_devel_kit-0.3.0/ --add-module=../lua-nginx-module-0.10.13/
[[email protected] nginx-1.13.6]# make -j2 && make install

8 .添加链接文件

[[email protected] src]# ln -s /usr/local/nginx-1.13.6 /usr/local/nginx
[[email protected] src]# ln -s /usr/local/lib/libluajit-5.1.so.2 /lib64/libluajit-5.1.so.2

应用配置

1 .调用lua测试，编辑Nginx.conf 添加/hello

[[email protected] conf]# vim /usr/local/nginx/conf/nginx.conf
worker_processes  auto;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
    server {
        listen       80;
        server_name  localhost;
        location / {
            root   html;
            index  index.html index.htm;
        }
        location /hello {
                default_type 'text/plain';
                content_by_lua 'ngx.say("hello,lua")';
        }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }
}

2 .语法检查并启动

[[email protected] conf]# /usr/local/nginx/sbin/nginx -t
[[email protected] conf]# /usr/local/nginx/sbin/nginx

[[email protected] conf]# curl 192.168.55.110/hello
hello,lua

WAF部署

1 .下载waf源码：

[[email protected] conf]# cd /usr/local/nginx/conf/
[[email protected] conf]# git clone https://github.com/loveshell/ngx_lua_waf.git
[[email protected] conf]# mv ngx_lua_waf/ waf 

2 .文件注释

config.lua     # 配置文件
init.lua       # 规则函数
waf.lua        # 逻辑关系
# wafconf      # 正则匹配关系目录
wafconf/args           # 里面的规则get参数进行过滤的
wafconf/url            # 是只在get请求url过滤的规则       
wafconf/post           # 是只在post请求过滤的规则     
wafconf/whitelist      # 是白名单，里面的url匹配到不做过滤     
wafconf/user-agent     # 是对user-agent的过滤规则

3 .config.lua 注释：

RulePath = "/usr/local/nginx/conf/waf/wafconf/"
--规则存放目录
attacklog = "off"
--是否开启攻击信息记录，需要配置logdir
logdir = "/usr/local/nginx/logs/hack/"
--log存储目录，该目录需要用户自己新建，切需要nginx用户的可写权限
UrlDeny="on"
--是否拦截url访问
Redirect="on"
--是否拦截后重定向
CookieMatch = "on"
--是否拦截cookie攻击
postMatch = "on" 
--是否拦截post攻击
whiteModule = "on" 
--是否开启URL白名单
black_fileExt={"php","jsp"}
--填写不允许上传文件后缀类型
ipWhitelist={"127.0.0.1"}
--ip白名单，多个ip用逗号分隔
ipBlocklist={"1.0.0.1"}
--ip黑名单，多个ip用逗号分隔
CCDeny="on"
--是否开启拦截cc攻击(需要nginx.conf的http段增加lua_shared_dict limit 10m;)
CCrate = "100/60"
--设置cc攻击频率，单位为秒.
--默认1分钟同一个IP只能请求同一个地址100次
html=[[Please go away~~]]
--警告内容,可在中括号内自定义
备注:不要乱动双引号，区分大小写

4 .修改Nginx配置文件引用WAF功能【http段加入】

    lua_shared_dict limit 50m;
    lua_package_path "/usr/local/nginx/conf/waf/?.lua";
    init_by_lua_file "/usr/local/nginx/conf/waf/init.lua";
    access_by_lua_file "/usr/local/nginx/conf/waf/waf.lua";

5 .详情：

[[email protected] conf]# cat nginx.conf
worker_processes  auto;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
    lua_shared_dict limit 50m;
    lua_package_path "/usr/local/nginx/conf/waf/?.lua";
    init_by_lua_file "/usr/local/nginx/conf/waf/init.lua";
    access_by_lua_file "/usr/local/nginx/conf/waf/waf.lua";
    server {
        listen       80;
        server_name  localhost;
        location / {
            root   html;
            index  index.html index.htm;
        }
        location /hello {
                default_type 'text/plain';
                content_by_lua 'ngx.say("hello,lua")';
        }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }
}

6 .创建日志目录给予www用户权限：

[[email protected] conf]# mkdir /usr/local/nginx/logs/hack/
[[email protected] conf]# chown www.www /usr/local/nginx/logs/hack/

7 .启动Nginx 并测试：

[[email protected] conf]# /usr/local/nginx/sbin/nginx -t
[[email protected] conf]# /usr/local/nginx/sbin/nginx -s reload 

8 .测试是否阻止请求：

http://192.168.55.110/hello?id=../etc/passwd

9 .通过ab模仿cc攻击：

[[email protected] waf]# ab -c 100 -n 1200 http://192.168.55.110/hello

一个页面版WAF--VeryNginx：https://github.com/alexazhou/VeryNginx