hood

Things of my MSc thesis about a firewall system for working in unsafe environments.

It's not hard to point out someone is wearing a hood, but the hood makes it harder to say who is wearing it.

Table of Contents

1. Status
2. Graphics to show the concept
3. Recommended hardware
4. Install to Raspberry Pi
5. Install to Debian
6. License

Status

Firewall hardware

• Raspberry Pi 4B
• Regular computer
• Others not tested

Operating systems to use the firewall

• Windows 10
• Linux (Raspberry Pi OS / Debian live / Parrot OS)
• Mac OS

Todo

1. Show realtime network activities on a screen
2. Support HTTP3 QUIC
3. Apply virtualization https://maimai.cn/web/feed_detail?fid=1733012779&efid=ntnLQCMgu6NRj1NgHnQ5gA

Graphics to show the concept

Recommended hardware

• SBC: Raspberry Pi 4B
• Screen: Waveshare 35a / Joy-IT RB-TFT3.5

Install to Raspberry Pi

If you already know how to write raspberrypi os image to a SD card, goto step 3

Step 1. Download the latest raspberrypi OS lite image (64bit)

curl -L -O -C - https://downloads.raspberrypi.com/raspios_lite_arm64/images/raspios_lite_arm64-2023-12-11/2023-12-11-raspios-bookworm-arm64-lite.img.xz

Step 2. Write the image to a SD card

xz -c -d 2023-12-11-raspios-bookworm-arm64-lite.img.xz | sudo dd of=/dev/sdX bs=4M status=progress

You may need lsblk command to locate the device name of your SD card.

Step 3. Get Hood

You can get it as a zip file from the Download ZIP button of the dropdown menu triggered by the Code button on the top.

Or you can use following command

git clone --depth=1 https://github.com/YongBinnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn/hood.git

Step 4. Install hood

Firstly, use lsblk command to check the device name of you SD card,

Then, use following command to ensure the partitions are not mounted (replace sdX with SD card device name)

sudo umount /dev/sdX*

Then, use following command to ensure the partitions are not mounted. Correct output is nothing (replace sdX with SD card device name)

mount|grep sdX

Then, start to install (replace sdX with SD card device name)

cd hood/scripts
./install.sh target=sdX

Commandline options available to the install script:

Name	Default Value	Description
usb_tether=	1	Share network to computer via USB cable
harden_only=	0	Only apply hardening parts. Let the target SBC can still be used as a computer.
disable_wireless=	1	Disable WiFi and Bluetooth.
disable_gpu=	1	Disable GPU.
debian_live	N/A	Install to live debian environment.
gpio_shutdown_pin=	21	The GPIO pin used for shutdown the computer
screen_dtbo=	OMITTED	The path of the dtbo file for the screen used for the computer
target=	/	The target root/device to install firewall.
wan_port_device_path=	auto-built-in-eth	The path of the device to be used as WAN port. auto-built-in-eth means find built-in Ethernet port automatically.

Install to Debian

Hood firewall now is possible to be installed to debian-based Linux systems. This feature has been tested in the live environment of Parrot OS 6.0.

Kernel parameters used by author when running Live CD.

On boot menu, press 'e' to goto edit prompt, and then add following to the end of the 'linux' line

efi=noruntime module_blacklist=mei,bluetooth,drm,wmi,i2c_smbus ipv6.disable=1 toram=filesystem.squashfs acpi=off

Step 1. Get Hood

git clone --depth=1 https://github.com/YongBinnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn/hood.git

Step 2. Install hood

cd hood/scripts
./install.sh debian_live

Step 3. Reboot

If your are using a live environment created by an ISO image, you may want soft-reboot

sudo systemctl soft-reboot

In other situations, a regular reboot would be a better choice.

License

hood by Bin Yong is licensed under CC BY-NC-ND 4.0