Android12.0 system restricts Internet access series iptables uses IOemNetd to realize the realization of shielding ip blacklist

1 Introduction

In the customized development of the 12.0 system rom, in the product requirements of the netd network module in the system, the function of shielding the ip address will be required to be set in the system. The iptables command in liunx is also more important, and then
come In the block of IOemNetd, the relevant function of blocking the ip blacklist is realized, that is, only
a certain URL can be blocked in the app, that is, except this URL, others can access the Internet, and finally implement the interface call in the framework custom service

2. The iptables of the system restricting Internet access series uses IOemNetd to realize the core class of the realization of the function of shielding the ip blacklist

        system\netd\server\binder\com\android\internal\net\IOemNetd.aidl
        system\netd\server\OemNetdListener.cpp
        system\netd\server\OemNetdListener.h

3. Analysis and implementation of the core functions of the iptables of the system restricting Internet access series using IOemNetd to realize the function of shielding the ip blacklist

In the android native system, iptables is very important in the network filtering packet module. Iptabels is a packet filtering firewall system integrated with the Linux kernel. Both linux and android include the function of Iptables.
Iptables facilitate better control of IP packet filtering and firewall configuration on a Linux system if the Linux system is connected to the Internet or a LAN, a server, or a proxy server that connects the LAN to the Internet.
Another important advantage of netfilter/iptables is that it gives the user complete control over firewall configuration and packet filtering. You can customize your own rules to meet your specific needs

The commonly used commands of iptables are as follows:
Command Description

-L --list <chain name