国产99视频在线观看蜜芽

杨长帆混在其中，却只盯着赵文华的脸色。Miss the original BUG, I still have more than 900 attack beads left in my box, which is quite good as gold smelting material.二顺媳妇瞪大眼睛：我家小鱼儿才七岁，能说给谁？这话谁说的？刘氏笑道：瞧嫂子问的，我听见也没往心里去。沉声道：何风，本将军还没死呢。或者驰骋疆场，指挥千军万马，铁蹄过处，将敌人的营寨夷为平地。When a client accesses a server's web service, The client sends a message to the network card, The tcp/ip stack is part of the kernel, Therefore, the client information is transferred to the web service in user space through the kernel's TCP protocol, At this time, the destination destination of the client message is on the socket (IP: Port) that the web service is listening for. When a web service needs to respond to a client request, The destination destination of the response message sent by the web service is the client, At this time, The IP and port that the web service listens on becomes the origin instead, As we said, Netfilter is the real firewall, It is part of the kernel, Therefore, if we want the firewall to achieve the goal of "fire prevention", You need to set up checkpoints in the kernel. All incoming and outgoing messages have to pass through these checkpoints. After checking, those that meet the release conditions can be released, while those that meet the blocking conditions need to be blocked. As a result, input checkpoints and output checkpoints appear. These checkpoints are not called "checkpoints" but "chains" in iptables.Disadvantages: The efficiency is a bit low, and the synchronization lock must be judged every time the instance is called.