Example of nginx ip blacklist dynamic ban

cd LuaJIT-2.0.5
make
make install PREFIX=/usr/local/luajit

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

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;
  }
 
  # Management information, visit this URL to view the IP blacklist information in nginx location /get-ipblacklist-info {
    access_by_lua_file conf/lua/get_ipblacklist_info.lua;
  }
 
  # Synchronize URL, call the URL through the scheduled task, and implement the scheduled refresh of IP blacklist from mysql to nginx location /sync-ipblacklist {
   access_by_lua_file conf/lua/sync_ipblacklist.lua;
  }
 
  # Production domain name configuration, all locations that need IP blacklist control must contain the following statement location / {
   access_by_lua_file conf/lua/check_realip.lua;
  }
 
}

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

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");

-- Call URL to view blacklist information -- 10,000 IPs consume less than 1.5M ngx.shared memory -- Getting all KEYs will block other normal requests from accessing ngx.shared memory, so only a few keys can be displayed 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

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

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, 1: invalid',
 `effective_hour` decimal(11,2) DEFAULT '24' COMMENT 'Effective period, unit: hours',
 `ip_source` varchar(255) COLLATE utf8mb4_bin DEFAULT NULL COMMENT 'Blacklist source',
 `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 'Remarks',
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;
 
 
CREATE PROCEDURE proc_ip_blacklist_status_update()
-- Change the expired IP status to invalid 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();