• fschl dotfiles
  • Questions this repos tries to answer
    • Firefox/Thunderbird customization
    • Security
      • SSH Hardening
      • SSH key generation
      • GnuPG
      • Managing logins & passphrases
      • Backup Secure Keys
      • Thumb Drive Setup
  • [0/5]
  • Moving to Arch

fschl dotfiles

Things that make my linux life more comfortable, portable and secure. For debian, or debian-based distros. using i3wm.org on the desktop.

Questions this repos tries to answer

• How long does it take for you to set up a machine?
• Do you have backups?
• Are you using a password manager?
• How do you transport your secrets?

• Can you get things done without your computer?

  • Rescue+Recover friends laptops/computers
  • panic-ops using a friends laptop

Firefox/Thunderbird customization

• goto .mozilla/firefox/<user-profile>/
• mkdir chrome/ && cp ~/dotfiles/userChrome.css ./chrome/
• open Firefox: about:config and set toolkit.legacyUserProfileCustomizations.stylesheets to true

Security

SSH Hardening

• https://blog.g3rt.nl/upgrade-your-ssh-keys.html
• https://stribika.github.io/2015/01/04/secure-secure-shell.html
• https://wiki.mozilla.org/Security/Guidelines/OpenSSH#OpenSSH_client
• see /etc/ssh/ssh_config and .ssh/config

SSH key generation

  # ED25519 keys are favored over RSA keys when backward compatibility ''is not required''.
  # This is only compatible with OpenSSH 6.5+ and fixed-size (256 bytes).
  $ ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519_host_$(date +%Y-%m-%d) -C "Key to HOST for user-xyz"

  # Fallback for really old systems (why do you still have those??)
  # RSA keys are favored over ECDSA keys when backward compatibility ''is required'',
  # thus, newly generated keys are always either ED25519 or RSA (NOT ECDSA or DSA).
  $ ssh-keygen -t rsa -b 8192 -f ~/.ssh/id_rsa_host_$(date +%Y-%m-%d) -C "Key to HOST for user-xyz"

  $ ssh-copy-id -i ~/.ssh/<file>.pub -p 22 user@host

GnuPG

• https://wiki.mozilla.org/Security/Key_Management
• https://keyring.debian.org/creating-key.html
• https://wiki.debian.org/Subkeys

~/.gnupg/gpg.conf:

personal-digest-preferences SHA512 SHA384
cert-digest-algo SHA256
default-preference-list SHA512 SHA384 AES256 ZLIB BZIP2 ZIP Uncompressed
keyid-format 0xlong

Managing logins & passphrases

• use a secure, cross-platform, cloudless password manager, e.g keepassXC

Backup Secure Keys

• get 2 USB thumb drives
• on each, create 2 partitions (ext4, you will never use them on any windows device anyway)
• https://wiki.archlinux.org/index.php/Dm-crypt/Device_Encryption

Nowadays it's mere chance to find a USB thumb drive with less than 4GB storage. Though, you want a dedicated drive to transport your password database, ssh keys and GPG keys. Those don't require more than a couple MB. So what to do with the remaining space?

Scenarios:

• You visit friends, only have your keys with you and you have to check your mails, assist a colleague in some network/ops emergency or just securely look up some confidential information.
• A family member calls: their HDD just died and you are asked to quickly help out on recovery.

Boot into a safe environment, having all your credentials available in a secure manner. Have a bootable forensics toolbox around to quickly get going in a familiar setup.

Solution: multi-boot!

Thumb Drive Setup

3 partitions: boot+isos, luks encrypted, unencrypted partition for non-sensitive data

TODO [0/5]

• explain setup, ideas, practises
• add HOWTO
• Check new bootable USB solution: https://ventoy.net/en/index.html
• move to ansible for easier modularization of setup
• OR: give GUIX a shot

Moving to Arch

• official repository setup: https://wiki.archlinux.org/title/Official_repositories#multilib

  • multiplib is required for wine
• Sound troubleshooting: https://wiki.archlinux.org/title/Advanced_Linux_Sound_Architecture/Troubleshooting#HDMI
• Skype, VSCode: use yay