Sharing a Network Connection with USB RNDIS¶

How to expose an Ethernet-over-USB interface using RNDIS in an embedded Linux device.

This English edition retains the original diagrams and practical code or command examples.

Reference diagram 1

Commands and examples¶

+---------------------------+
|       用户空间应用层        |  <- 例如，通过 `ifconfig` 或 `ip` 命令配置网络
+---------------------------+
              |
+---------------------------+
|     网络协议栈层（Linux）    |  <- 网络协议栈，如 TCP/IP、UDP 等
+---------------------------+
              |
+---------------------------+
|      内核网络驱动层         |  <- RNDIS 驱动，负责 USB 网络设备的初始化与数据传输
+---------------------------+
              |
+---------------------------+
|       USB 核心驱动层        |  <- 处理 USB 设备的通信，支持 RNDIS 设备
+---------------------------+
              |
+---------------------------+
|     USB 设备硬件层         |  <- 设备本身，支持 USB 规范并实现 RNDIS 协议
+---------------------------+

grep RNDIS /boot/config-$(uname -r)

modprobe rndis_host

lsusb

ifconfig -a

sudo ifconfig usb0 192.168.0.1 netmask 255.255.255.0 up

sudo dhclient usb0

sudo ifconfig usb0 192.168.0.2 netmask 255.255.255.0 up

ping 192.168.0.2

ping 192.168.0.1

scp testfile.txt [email protected]:/home/user/

scp [email protected]:/home/user/testfile.txt /local/destination/

dmesg | grep usb

Practical notes¶

Validate pin multiplexing, clocks, power sequencing, kernel configuration, and device-tree bindings on the target board before drawing conclusions from a test result.