OpenWRT Raspi travel-router build script

Multi-WAN tethering plus hotel captive portal auth & VPN support.

This OpenWRT build script & configuration files creates a Raspberry Pi 3 or 4 image supporting:

• Multiple WAN connection options:
  • Wifi as a WAN client
  • Built-in Ethernet as WAN client
  • iPhone tethering as WAN client
  • Android tethering as WAN client
  • Automatic WAN failover if multiple WAN connections exist
• Packet TTL fixes to hide device sharing from upstream carriers
• The Luci "Travelmate" hotel captive portal GUI add-on

Instructions

Step 1.

Research and obtain a Linux compatible USB Wifi adapter with a chipset that supports "AP mode".

(Built-in Raspi radio supports AP Mode and will be used for hotel Wifi piggyback, a second USB wifi dongle also supporting AP Mode will be needed to service Wifi clients).

---

Step 2.

Next confirm that the chipset of your USB wifi adapter is supported in OpenWRT:

• Search https://forum.openwrt.org to confirm and obtain the correct package name(s) of the OpenWRT wifi chipset packages required.
• To learn more about USB wifi adapters with Linux/OpenWRT & AP mode support see here: https://github.com/morrownr/USB-WiFi.

---

Step 3.

• Download raspi-travelrouter.sh script and make it executable: chmod +x raspi-travelrouter.sh.

• Download base-travelrouter-raspi.tar.gz and extract the contents.

---

Step 4.

Adjust the ARCH= & IMAGE_PROFILE= sections of raspi-travelrouter.sh to suit your Raspi hardware (script defaults build for Raspi 4).

 ARCH="???"           # Set to ARCH="bcm2710" for Raspi3 or ARCH="bcm2711" for Raspi4 
 IMAGE_PROFILE="???"  # Set to IMAGE_PROFILE="rpi-3" or IMAGE_PROFILE="rpi-4"

---

Step 5.

On the last line of the CUSTOM_PACKAGES section at the top of the raspi-travelrouter.sh script, add the USB device driver package names you confirmed in Step 2 above. (The USB chipset packages included in the default script are examples and can be removed. See script comments for more).

You can add any number of other OpenWRT packages in the CUSTOM_PACKGES section to create your own custom travel-router recipe.

---

Step 6.

Run the script as sudo and follow the prompts: sudo ./raspi-travelrouter.sh. When prompted to add custom OpenWRT config files, copy the unzipped contents of base-travelrouter-raspi.tar.gz to $(pwd)/openwrt_inject_files and hit enter to start the build.

---

Step 7.

When the OpenWRT build has completed, several newly built firmwares can be found under $(pwd)/firmware_images.

SquashFS will be the best choice for most use cases on Raspi. Flash your choice of image to MMC in your preferred way, insert it into your Raspberry Pi and boot.

---

Step 8.

After first boot give your Raspi a few minutes to settle before trying to connect to the default "OpentWRT" SSID (no password).

When connected, browse to http://10.1.10.1 to reach the OpenWRT Luci GUI. Use Luci to add an OpenWRT admin password and change the SSID name to something stealthy.

• To configure an upstream hotel wifi network as WAN, in Luci look for the Travelmate page.
• If using a tethered phone or direct ethernet for WAN, internet access will automatically be shared by the travel-router's new & stealthy SSID.

---

Step 9.

Optional. If you wire a power button across gpio_pin3 (Pin5) and any ground pin, adding dtoverlay=gpio-shutdown,gpio_pin=3 to /boot/config.txt enables both power ON and SHUTDOWN functionality.

Image courtesy https://github.com/Howchoo/pi-power-button

---