nginx ip黑名单动态封禁的例子

Z时代
2024-01-10
分类：IT

网站被恶意请求，拉黑IP是重要的手段，如果每次拉黑都要到nginx上配置，未免太low了；我们需要更方便的控制nginx IP黑名单。

1.方案

黑名单持久化到mysql （常见的方案是redis，但不利于控制，如：不同的IP设置不同的有效期、IP的CRUD、统计等等）；

通过lua-nginx-module，在nginx中开辟一块内存（lua_shared_dict），lua将黑名单定期从mysql全量刷新至lua_shared_dict；

所有请求，都要到与lua_shared_dict中的IP check一下。

2.安装

2.1 安装luajit

cd LuaJIT-2.0.5

make

make install PREFIX=/usr/local/luajit

2.2.安装nginx时，将lua模块编译进去

export LUAJIT_LIB=/usr/local/luajit/lib

export LUAJIT_INC=/usr/local/luajit/include/luajit-2.1

./configure --prefix=/nginx \

--with-ld-opt="-Wl,-rpath,/usr/local/luajit/lib" \

--add-module=/opt/ngx_devel_kit-0.3.1rc1 \

--add-module=/opt/lua-nginx-module-0.10.14rc3

make -j2

make install

ln -s /nginx/sbin/nginx /usr/sbin/nginx

3.配置

3.1 nginx配置


http {
  server_tokens off;
  lua_package_path "/usr/local/lib/lua/?.lua;;";
  lua_shared_dict ip_blacklist 4m;
}
server {
  set $real_ip $remote_addr;
  if ( $http_x_forwarded_for ~ "^(\d+\.\d+\.\d+\.\d+)" ) {
    set $real_ip $1;
  }
  # 管理信息，访问该URL可以查看nginx中的IP黑名单信息
  location /get-ipblacklist-info {
    access_by_lua_file conf/lua/get_ipblacklist_info.lua;
  }
  # 同步URL，通过定时任务调用该URL,实现IP黑名单从mysql到nginx的定时刷新
  location /sync-ipblacklist {
   access_by_lua_file conf/lua/sync_ipblacklist.lua;
  }
  # 生产域名配置，所有需要IP黑名单控制的location，都要包含以下语句
  location / {
   access_by_lua_file conf/lua/check_realip.lua;
  }
}

nginx服务器配置以下crrontab

* * * * * /usr/bin/curl -o /dev/null -s http://127.0.0.1/sync-ipblacklist > /dev/null 2>&1

3.2 lua脚本

sync_ipblacklist.lua


local mysql_host = "ip of mysql server"
local mysql_port = 3306
local database = "dbname"
local username = "user"
local password = "password"
-- update ip_blacklist from mysql once every cache_ttl seconds
local cache_ttl  = 1
local mysql_connection_timeout = 1000
local client_ip  = ngx.var.real_ip
local ip_blacklist  = ngx.shared.ip_blacklist
local last_update_time = ip_blacklist:get("last_update_time");
if last_update_time == nil or last_update_time < ( ngx.now() - cache_ttl ) then
 local mysql = require "resty.mysql";
 local red = mysql:new();
 red:set_timeout(mysql_connect_timeout);
 local ok, err, errcode, sqlstate = red:connect{
     host = mysql_host,
     port = mysql_port,
     database = database,
     user = username,
     password = password,
     charset = "utf8",
     max_packet_size = 1024 * 1024,
    }
 if not ok then
 ngx.log(ngx.ERR, "mysql connection error while retrieving ip_blacklist: " .. err);
 else
 new_ip_blacklist, err, errcode, sqlstate = red:query("select ip_addr from ip_blacklist where status = 0 order by create_time desc limit 10000", 100)
 if not new_ip_blacklist then
  ngx.log(ngx.ERR, "bad result. errcode: " .. errcode .. " sqlstate: " .. sqlstate .. " err: " .. err);
  return
 end
 ip_blacklist:flush_all();
 for k1, v1 in pairs(new_ip_blacklist) do
  for k2, v2 in pairs(v1) do
  ip_blacklist:set(v2,true);
  end
 end
 ip_blacklist:set("last_update_time", ngx.now());
 end
end
ngx.say("sync successful");

get_ipblacklist_info.lua


-- 调用URL查看黑名单信息
-- 1万IP消耗不到1.5M ngx.shared内存
-- 获取所有KEY会堵塞别的正常请求对ngx.shared内存的访问，因此只能取少数key展示
require "resty.core.shdict"
ngx.say("total space: " .. ngx.shared.ip_blacklist:capacity() .. "<br/>");
ngx.say("free space: " .. ngx.shared.ip_blacklist:free_space() .. "<br/>");
ngx.say("last update time: " .. os.date("%Y%m%d_%H:%M:%S",ngx.shared.ip_blacklist:get("last_update_time")) .. "<br/>");
ngx.say("first 100 keys: <br/>");
ngx.say("--------------------------<br/>");
ip_blacklist = ngx.shared.ip_blacklist:get_keys(100);
for key, value in pairs(ip_blacklist) do
 ngx.say(key .. ": " .. value .. "<br/>");
end

check_realip.lua


if ngx.shared.ip_blacklist:get(ngx.var.real_ip) then
 return ngx.exit(ngx.HTTP_FORBIDDEN);
end

3.3 数据库设计


CREATE TABLE `ip_blacklist` (
 `id` int(11) NOT NULL AUTO_INCREMENT,
 `ip_addr` varchar(15) COLLATE utf8mb4_bin DEFAULT NULL,
 `status` int(11) DEFAULT '0' COMMENT '0: valid 有效, 1: invalid 失效',
 `effective_hour` decimal(11,2) DEFAULT '24' COMMENT '有效期，单位：小时',
 `ip_source` varchar(255) COLLATE utf8mb4_bin DEFAULT NULL COMMENT '黑名单来源',
 `create_time` datetime DEFAULT CURRENT_TIMESTAMP,
 `modify_time` datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
 `remark` varchar(255) COLLATE utf8mb4_bin DEFAULT NULL COMMENT '备注',
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;
CREATE PROCEDURE proc_ip_blacklist_status_update()
-- 将过期的IP状态改为失效
begin 
 update ip_blacklist
 set status=1
 where date_add(create_time,INTERVAL effective_hour hour) < now();
 commit;
end;
CREATE EVENT job_ip_blacklist_status_update
ON SCHEDULE EVERY 1 MINUTE
ON COMPLETION PRESERVE
ENABLE
DO
call proc_ip_blacklist_status_update();