Beaglebone Setup

beaglebone.org

Beaglebone Black Setup from a Debian 8 laptop

Grab the debian image from http://beagleboard.org

1. Download Debian image [whatever].img.xz to your laptop
   • http://beagleboard.org/latest-images
2. unxz bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img.xz
3. Insert microSD card and make sure that it is unmounted
   • lsblk
   • fdisk -l
4. sudo dd bs=4 if=bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img of=/dev/sdd conv=fsync
5. put sdcard in BBB and power up

Connect over SSH

1. Plugin beaglebone to computer via SSH
2. ssh -l root 192.168.7.2

Wifi Setup

1. Plugin the wifi adapter
2. Reboot (unplug it and plug it back in)
3. vim /etc/network/interfaces

   auto wlan0
   iface wlan0 inet dhcp
       wpa-ssid "network-name"
       wpa-psk "network-password"
       

4. ifdown wlan0; ifup wlan0
5. use ip -o addr show to confirm that you have an ip address

Update debian

• Use the Debian Upgrade Script to update debian:

#!/usr/bin/env bash
# Debian auto-upgrade script
# https://debian-handbook.info/browse/stable/sect.automatic-upgrades.html

# kill all cached creds
sudo -k

# ask for new creds
sudo -v

export DEBIAN_FRONTEND=noninteractive
sudo apt-get update
yes '' | sudo apt-get -y -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" dist-upgrade

Basic security

Make a root password

• Install pwgen: sudo apt-get install pwgen
• Generate a root password: pwgen -Bsy 16 1
• Store that password in your password store—you’ll never remember it
• Login to beaglebone via ssh, run passwd

Add a privileged non-root user

• Generate a non-privileged user password: pwgen -Bsy 16 1
• Save password in password store
• Add the user

  sudo groupadd sudo-user
  sudo groupadd ssh-user
  useradd tyler
  mkdir /home/tyler
  mkdir /home/tyler/.ssh
  touch /home/tyler/.ssh/authorized_keys
  chown -R tyler:tyler /home/tyler
  chmod 700 /home/tyler/.ssh
  chmod 600 /home/tyler/.ssh/authorized_keys
  usermod -a -G sudo-user tyler
  usermod -a -G ssh-user tyler
  usermod --shell /bin/bash tyler
  passwd tyler
      

• give that user sudo privileges
  • EDITOR=vim visudo -f /etc/sudoers.d/sudo-user
  • Add the line: %sudo-user ALL=(ALL) NOPASSWD:ALL
• Add your laptop’s key to user’s authorized_keys

  # This should happen from your local machine: laptop/desktop/whatever
  cat ~/.ssh/id_rsa.pub | ssh -l tyler 192.168.7.2 'mkdir -p .ssh && cat >> ~/.ssh/authorized_keys'
      

Remove demo user

• userdel -fr debian

Lockdown ssh

• Generate better hostkeys

  cd /etc/ssh
  rm ssh_host_*key*
  ssh-keygen -t rsa -b 4096 -f ssh_host_rsa_key < /dev/null
      

• Modfiy /etc/ssh/sshd_config to make it like below:

  Ciphers aes256-ctr,aes192-ctr,aes128-ctr
  KexAlgorithms diffie-hellman-group-exchange-sha256
  MACs hmac-sha2-512,hmac-sha2-256,hmac-ripemd160
  Protocol 2
  HostKey /etc/ssh/ssh_host_rsa_key
  PubkeyAuthentication yes
  PermitRootLogin no
  PasswordAuthentication no
  AllowGroups ssh-user
      

• Restart SSH service ssh restart
• Open a new terminal window and make sure you can still login (you may need to delete and reaccept hostkeys)

Fun Stuff

• Change ssh banner:

  sudo apt-get install figlet
  awk '$1 !~ /default/' /etc/issue.net > ~/issue.net && sudo mv ~/issue.net /etc/issue.net
  sudo sh -c 'figlet BeagleBone >> /etc/issue.net'