airgap/README.md

2.6 KiB

AirgapOS

https://git.distrust.co/public/airgap

About

A full-source-bootstrapped, deterministic, minimal, immutable, and offline, workstation linux distribution designed for creating and managing secrets offline.

Built for those of us that want to be -really- sure our most important secrets are managed in a clean environment with an "air gap" between us and the internet with high integrity on the supply chain of the firmware and OS used.

Uses

  • Generate PGP keychain
  • Store/Restore gpg keychain to security token such as a Yubikey or Nitrokey
  • Signing cryptocurrency transactions
  • Generate/backup BIP39 universal cryptocurrency wallet seed
  • Store/Restore BIP39 seed to a hardware wallet such as a Trezor or Ledger

Features

  • Deterministic iso generation for multi-party code->binary verification
  • Small footprint (< 100MB)
  • Immutable and Diskless: runs from initramfs
  • Network support and most drivers removed to minimize exfiltration vectors

Requirements

Software

  • docker 26+

Hardware

  • x86_64 PC or laptop
    • linuxboot/heads firmware supported and recommended for multi-use machine
      • Allows for signed builds, and verification of signed sd card payloads
    • Ensure any Wifi/Disk/Bluetooth/Audio devices are disabled/removed
  • Blank flash drive
  • Blank SD card

Build

Update git submodules

git submodule update --init --recursive

Build a new release

make release

Reproduce an existing release

make attest

Sign an existing release

make sign

Provisioning

  1. Write airgap.iso to CD-ROM or SD Card a. dd if=out/airgap.iso of=/dev/sda bs=1M conv=sync status=progress b. cdrecord out/airgap.iso

  2. Verify media still produces expected hash

sha256sum out/airgap.iso
head -c $(stat -c '%s' airgap.iso) /dev/sda | sha256sum

Setup

Assumes target is running Pureboot or Coreboot/heads

  1. Boot to shell: Options -> Recovery Shell
  2. Mount SD card
    mount-usb
    mount -o remount,rw /media
    
  3. Insert chosen GPG Smartcard device
  4. Initialize smartcard
    gpg --card-status
    
  5. Sign target iso
    cd /media
    gpg --armor --detach-sign airgap.iso
    
  6. Unmount
    cd
    umount /media
    sync
    
  7. Reboot

Usage

  1. Insert remote attestation device
  2. Power on, and verify successful remote attestation
  3. Boot to airgap via: Options -> Boot Options -> USB Boot

Development

Build develop image

make

Boot image in qemu

make vm

Enter shell in build environment

make shell